Measures for the detection of localized corrosion with electrochemical noise

Determination of Pesticide Minimum Residue Limits in Essential OilsReport No 3A report for the Rural Industries Research andDevelopment CorporationBy Professor R. C. Menary & Ms S. M. GarlandJune 2004RIRDC Publication No 04/023RIRDC Project No UT-23A© 2004 Rural Industries Research and Development Corporation.All rights reserved.ISBN 0642 58733 7ISSN 1440-6845‘Determination of pesticide minimum residue limits in essential oils’, Report No 3Publication No 04/023Project no.UT-23AThe views expressed and the conclusions reached in this publication are those of the author and not necessarily those of persons consulted. RIRDC shall not be responsible in any way whatsoever to any person who relies in whole or in part on the contents of this report.This publication is copyright. However, RIRDC encourages wide dissemination of its research, providing the Corporation is clearly acknowledged. For any other enquiries concerning reproduction, contact the Publications Manager on phone 02 6272 3186.Researcher Contact DetailsProfessor R. C. Menary & Ms S. M. GarlandSchool of Agricultural ScienceUniversity of TasmaniaGPO Box 252-54HobartTasmania 7001AustraliaPhone: (03) 6226 2723Fax: (03) 6226 7609Email: r.menary@.auIn submitting this report, the researcher has agreed to RIRDC publishing this material in its edited form.RIRDC Contact DetailsRural Industries Research and Development CorporationLevel 1, AMA House42 Macquarie StreetBARTON ACT 2600PO Box 4776KINGSTON ACT 2604Phone: 02 6272 4819Fax: 02 6272 5877Email: rirdc@.auWebsite: .auPublished in June 2004Printed on environmentally friendly paper by Canprint.FOREWORDInternational regulatory authorities are standardising the levels of pesticide residues present in products on the world market which are considered acceptable. The analytical methods to be used to confirm residue levels are also being standardised. To constructively participate in these processes, Australia must have a research base capable of constructively contributing to the establishment of methodologies and must be in a position to assess the levels of contamination within our own products.Methods for the analysis for pesticide residues rarely deal with their detection in the matrix of essential oils. This project is designed to develop and validate analytical methods and apply that methodology to monitor pesticide levels in oils produced from commercial harvests. This will provide an overview of the levels of pesticide residues we can expect in our produce when normal pesticide management programs are adhered to.The proposal to produce a manual which deals with the specific problems associated with detection of pesticide residues in essential oils is intended to benefit the essential oil industry throughout Australia and may prove useful to other horticultural products.This report is the third in a series of four project reports presented to RIRDC on this subject. It is accompanied by a technical manual detailing methodologies appropriate to the analysis for pesticide residues in essential oils.This project was part funded from RIRDC Core Funds which are provided by the Australian Government. Funding was also provided by Essential Oils of Tasmania and Natural Plant Extracts Cooperative Society Ltd.This report, an addition to RIRDC’s diverse range of over 1000 research publications, forms part of our Essential Oils and Plant Extracts R&D program, which aims for an Australian essential oils and plant extracts industry that has established international leadership in production, value adding and marketing.Most of our publications are available for viewing, downloading or purchasing online through our website:•downloads at .au/fullreports/index.html•purchases at .au/eshopSimon HearnManaging DirectorRural Industries Research and Development CorporationAcknowledgementsOur gratitude and recognition is extended to Dr. Noel Davies (Central Science Laboratories, University of Tasmania) who provided considerable expertise in establishing procedures for chromatography mass spectrometry.The contribution to extraction methodologies and experimental work-up of Mr Garth Oliver, Research Assistant, cannot be underestimated and we gratefully acknowledge his enthusiasm and novel approaches.Financial and ‘in kind’ support was provided by Essential Oils Industry of Tasmania, (EOT).AbbreviationsADI Average Daily IntakeAGAL Australian Government Analytical Laboratoriesingredientai activeAPCI Atmospheric Pressure Chemical IonisationBAP Best Agricultural PracticesenergyCE collisionDETA DiethylenetriamineECD Electron Capture DetectorionisationESI ElectrosprayFPD Flame Photometric DetectionChromatographyGC GasResolutionHR HighChromatographyLC LiquidLC MSMS Liquid Chromatography with detection monitoring the fragments of Mass Selected ionsMRL Maximum Residue LimitSpectrometryMS MassNRA National Registration AuthorityR.S.D. Relative Standard DeviationSFE Supercritical Fluid ExtractionSIM Single Ion MonitoringSPE Solid Phase ExtractionTIC Total Ion ChromatogramContents FOREWORD (III)ACKNOWLEDGEMENTS (IV)ABBREVIATIONS (V)CONTENTS (VI)EXECUTIVE SUMMARY (VII)1. INTRODUCTION (1)1.1B ACKGROUND TO THE P ROJECT (1)1.2O BJECTIVES (2)1.3M ETHODOLOGY (2)2. EXPERIMENTAL PROTOCOLS & DETAILED RESULTS (3)2.1M ETHOD D EVELOPMENT (3)2.2M ONITORING OF H ARVESTS (42)2.3P RODUCTION OF M ANUAL (46)3. CONCLUSIONS (47)IMPLICATIONS & RECOMMENDATIONS (50)BIBLIOGRAPHY (50)Executive SummaryThe main objective of this project was to continue method development for the detection of pesticide residues in essential oils, to apply those methodologies to screen oils produced by major growers in the industry and to produce a manual to consolidate and coordinate the results of the research. Method development focussed on the effectiveness of clean-up techniques, validation of existing techniques, the assessment of the application of gas chromatography (GC) with detection using electron capture detectors (ECD), flame photometric detectors (FPD) and high pressure liquid chromatography (HPLC) with ion trap mass selective (MS) detection.The capacity of disposable C18 cartridges to separate components of boronia oil was found to be limited with the majority of boronia components being eluted on the solvent front, with little to no separation achieved. The cartridges were useful, however, in establishing the likely interaction of reverse phases (RP) C18 columns with components of essential oils, using polar mobile phases . The loading of large amounts of oil onto RP HPLC columns presents the risk of permanently contaminating the bonded phases. The lack of retention of components on disposable SPE C18 cartridges, despite the highly polar mobile phase, presented a good indication that essential oils would not accumulate on HPLC RP columns.The removal of non-polar essential oil components by solvent partitioning of distilled oils was minimal, with the recovery of pesticides equivalent to that recorded for the essential oil components. However application of this technique was of advantage in the analysis of solvent extracted essential oils such as those produced from boronia and blackcurrant.ECD was found to be successful in the detection of terbacil, bromacil, haloxyfop ester, propiconazole, tebuconazole and difenaconzole. However, analysis of pesticide residues in essential oils by application of GC ECD is not sufficiently sensitive to allow for a definitive identification of any contaminant. As a screen, ECD will only be effective in establishing that, in the absence of a peak eluting with the correct retention time, no gross contamination of pesticide residues in an essential oil has occurred . In the situation where a peak is recorded with the correct elution characteristics, and which is enhanced when the sample is fortified with the target analyte, a second means of contaminant identification would be required. ECD, then, can only be used to rule out significant contamination and could not in itself be adequate for a positive identification of pesticide contamination.Benchtop GC daughter, daughter mass spectrometry (MSMS) was assessed and was not considered practical for the detection of pesticide residues within the matrix of essential oils without comprehensive clean-up methodologies. The elution of all components into the mass spectrometer would quickly lead to detector contamination.Method validation for the detection of 6 common pesticides in boronia oil using GC high resolution mass spectrometry was completed. An analytical technique for the detection of monocrotophos in essential oils was developed using LC with detection by MSMS. The methodology included an aqueous extraction step which removed many essential oil components from the sample.Further method development of LC MSMS included the assessment of electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI. For the chemicals trialed, ESI has limited application. No response was recorded for some of the most commonly used pesticides in the essential oil industry, such as linuron, oxyflurofen, and bromacil. Overall, there was very little difference between the sensitivity for ESI and APCI. However, APCI was slightly more sensitive for the commonly used pesticides, tebuconazole and propiconazole, and showed a response, though poor, to linuron and oxyflurofen. In addition, APCI was the preferred ionisation method for the following reasons,♦APCI uses less nitrogen gas compared to ESI, making overnight runs less costly;♦APCI does not have the high back pressure associated with ionisation by ESI such that APCI can be run in conjunction with UV-VIS without risk of fracturing the cell, which is pressure sensitive. Analytes that ionised in the negative APCI mode were incorporated into a separate screen which included bromacil, terbacil, and the esters of the fluazifop and haloxyfop acids. Further work using APCI in the positive mode formed the basis for the inclusion of monocrotophos, pirimicarb, propazine and difenaconazole into the standard screen already established. Acephate, carbaryl, dimethoate, ethofumesate and pendimethalin all required further work for enhanced ionisation and / or improved elution profiles. Negative ionisation mode for APCI gave improved characteristics for dicamba, procymidone, MCPA and mecoprop.The thirteen pesticides included in this general screen were monocrotophos, simazine, cyanazine, pirimicarb, propazine, sethoxydim, prometryb, tebuconazole, propiconazole, , difenoconazole and the esters of fluroxypyr, fluazifop and haloxyfop.. Bromacil and terbacil were not included as both require negative ionisation and elute within the same time window as simazine, which requires positive ionisation. Cycling the MS between the two modes was not practical.The method validation was tested against three oils, peppermint, parsley and fennel.Detection limits ranged from 0.1 to 0.5 mgkg-1 within the matrix of the essential oils, with a linear relationship established between pesticide concentration and peak height (r2 greater than 0.997) and repeatabilities, as described by the relative standard deviation (r.s.d), ranging from 3 to 19%. The type of oil analysed had minimal effect on the response function as expressed by slope of the standard curve.The pesticides which have an carboxylic acid moiety such as fluazifop, haloxyfop and fluroxypyr, present several complications in any analytical method development. The commercial preparations usually have the carboxylic acid in the ester form, which is hydrolysed to the active acidic form on contact with soil and vegetation. In addition, the esters may be present in several forms, such as the ethoxy ethyl or butyl esters. Detection using ESI was tested. Preliminary results indicate that ESI is unsuitable for haloxyfop and fluroxypyr ester. Fluazifop possessed good ionisation characteristics using ESI, with responses approximately thirty times that recorded for haxloyfop. Poor chromatography and response necessitated improved mobile phase and the effect of pH on elution characteristics was considered the most critical parameter. The inclusion of acetic acid improved peak resolution.The LC MSMS method for the detection of dicamba, fluroxypyr, MCPA, mecoprop and haloxyfop in peppermint and fennel distilled oils underwent the validation process. Detection limits ranged from 0.01 to 0.1 mgkg-1Extraction protocols and LC MSMS methods for the detection of paraquat and diquat were developed. ESI produced excellent responses for both paraquat and diquat, after some modifications of the mobile phase. Extraction methodology using aqueous phases were developed. Extraction with carbonate buffer proved to be the most effective in terms of recovery and robustness. A total ion chromatogram of the LC run of an aqueous extract of essential oil was recorded and detection using a photodiode array detector confirmed that very little essential oil matrix was co-extracted. The low background noise indicated that samples could be introduced directly into the MS. This presented a most efficient and rapid way for analysis of paraquat and diquat, avoiding the need for specialised columns or modifiers to be included in the mobile phase to instigate ion exchange.The adsorbtion of paraquat and diquat onto glass and other surfaces was reduced by the inclusion of diethylenetriamine (DETA). DETA preferentially accumulates on the surfaces of sample containers, competitively binding to the adsorption sites. All glassware used in the paraquat diquat analysis were washed in a 5% solution of 0.1M DETA, DETA was included in all standard curve preparations, oils were extracted with aqueous DETA and the mobile phase was changed to 50:50 DETA / methanol. The stainless steel tubing on the switching valve was replaced with teflon, further improvingreproducibility. Method validation was undertaken of the analysis of paraquat and diquat using the protocols established. The relationship between analyte concentration and peak area was not linear at low concentrations, with adsorption more pronounced for paraquat, such that the response for this analyte was half that seen for diquat and the 0.1 mgkg-1 level.The development of a method for the detection of the dithiocarbamate, mancozeb was commenced. Disodium N, N'-ethylenebis(dithiocarbamate) was synthesised as a standard for the derivatised final analytical product. An LC method, with detection using MSMS, was successfully completed. The inclusion of a phase transfer reagent, tetrabutylammonium hyrdrogen sulfate, required in the derivatisation step, contaminated the LC MSMS system, such that any signal from the target analyte was masked. Alternatives to the phase transfer reagent are now being investigated.Monitoring of harvests were undertaken for the years spanning 1998 to 2001. Screens were conducted covering a range of solvent extracted and distilled oils. Residues tested for included tebuconazole, simazine, terbacil, bromacil, sethoxydim, prometryn, oxyflurofen, pirimicarb, difenaconazole, the herbicides with acidic moieties and paraquat and diquat. Problems continued for residues of propiconazole in boronia in the 1998 / 1999 year with levels to 1 mgkg-1 still being detected. Prometryn residues were detected in a large number of samples of parsley oil.Finally the information gleaned over years of research was collated into a manual designed to allow intending analysts to determine methodologies and equipment most suited to the type of the pesticide of interest and the applicability of analytical equipment generally available.1. Introduction1.1 Background to the ProjectResearch undertaken by the Horticultural Research Group at the University of Tasmania, into pesticide residues in essential oils has been ongoing for several years and has dealt with the problems specific to the analysis of residues within the matrix of essential oils. Analytical methods for pesticides have been developed exploiting the high degree of specificity and selectivity afforded by high resolution gas chromatography mass spectrometry. Standard curves, reproducibility and detection limits were established for each. Chemicals, otherwise not amenable to gas chromatography, were derivatised and incorporated into a separate screen to cover pesticides with acidic moieties.Research has been conducted into low resolution GC mass selective detectors (MSD and GC ECD. Low resolution GC MSD achieved detection to levels of 1 mgkg-1 in boronia oil, whilst analysis using GC ECD require a clean-up step to effectively detect halogenated chemicals below 1mgkg-1.Dithane (mancozeb) residues were digested using acidified stannous chloride and the carbon disulphide generated from this reaction analysed by GC coupled to FPD in the sulphur mode.Field trials in peppermint crops were established in accordance with the guidelines published by the National Registration Authority (NRA), monitoring the dissipation of Tilt and Folicur residues in peppermint leaves and the co-distillation of these residues with hydro-distilled peppermint oils were assessed.Development of extraction protocols, analytical methods, harvest monitoring and field trials were continued and were detailed in a subsequent report. Solvent-based extractions and supercritical fluid extraction (SFE) was found to have limited application in the clean-up of essential oilsIn conjunction with Essential Oils of Tasmania (EOT), the contamination risk, associated with the introduction of a range of herbicides, was assessed through a series of field trials. This required analytical method development to detect residues in boronia flowers, leaf and oil. The methodology for a further nine pesticides was successful applied. Detection limits for these chemicals ranged from 0.002 mgkg-1 to 0.1 mgkg-1. In addition, methods were developed to analyse for herbicides with active ingredients (ai) whose structure contained acidic functional groups. Two methods of pesticide application were trialed. Directed sprays refer to those directed on the stems and leaves of weeds at the base of boronia trees throughout the trial plot. Cover sprays were applied over the entire canopy. For all herbicides for which significant residues were detected, it was evident that cover sprays resulted in contamination levels ten times those occurring as a result of directed spraying in some instances. Chloropropham, terbacil and simazine presented potentially serious residue problems, with translocation of the chemical from vegetative material to the flower clearly evident.Directed spray applications of diuron and dimethenamid presented only low residue levels in extracted flowers with adequate control of weeds. Oxyflurofen and the mixture of bromacil and diuron (Krovar) presented only low levels of residues when used as a directed spray and were effective as both post and pre-emergent herbicides. Only very low levels of residues of both sethoxydim and norflurazon were detected in boronia oil produced in crops treated with directed spray applications. Sethoxydim was effective as a cover spray for grasses whilst norflurazon showed potential as herbicide to be used in combination with other chemicals such as diuron, paraquat and diquat. Little contamination of boronia oils by herbicides with acidic moieties was found. This advantage, however, appears to be offset by the relatively poor weed control. Both pendimethalin and haloxyfop showed good weed control. Both, however, present problems with chemical residues in boronia oil and should only be used as a directed sprayThe stability of tebuconazole, monocrotophos and propiconazole in boronia under standard storage conditions was investigated. Field trials of tebuconazole and propiconazole were established in commercial boronia crops and the dissipation of both were monitored over time. The amount of pesticide detected in the oils was related to that originally present in the flowers from which the oils were produced.Experiments were conducted to determine whether the accumulation of terbacil residues in peppermint was retarding plant vigour. The level recorded in the peppermint leaves were comparatively low. Itis unlikely that terbacil carry over is the cause for the lack of vigour in young peppermint plants.Boronia oils produced in 1996, 1997 and 1998 were screened for pesticides using the analytical methods developed. High levels of residues of propiconazole were shown to persist in crops harvested up until 1998. Field trials have shown that propiconazole residues should not present problems if the fungicide is used as recommended by the manufacturers.1.2 Objectives♦Provide the industry, including the Standards Association of Australia Committee CH21, with a concise practical reference, immediately relevant to the Australian essential oil industry♦Facilitate the transfer of technology from a research base to practical application in routine monitoring programs♦Continue the development of analytical methods for the detection of metabolites of the active ingredients of pesticide in essential oils.♦Validate the methods developed.♦Provide industry with data supporting assurances of quality for all exported products.♦Provide a benchmark from which Australia may negotiate the setting of a realistic maximum residue limit (MRL)♦Determine whether the rate of uptake is relative to the concentration of active ingredient on the leaf surface may establish the minimum application rates for effective pest control.1.3 MethodologyThree approaches were used to achieve the objectives set out above.♦Continue the development and validation of analytical methods for the detection of pesticide residues in essential oils. Analytical methods were developed using gas chromatography high resolution mass spectrometry (GC HR MS), GC ECD, GC FPD and high pressure liquid chromatography with detection using MSMS.♦Provide industry with data supporting assurances of quality for all exported products.♦Coordinate research results into a comprehensive manual outlining practical approaches to the development of analytical proceduresOne aspect of the commissioning of this project was to provide a cost effective analytical resource to assess the degree of the pesticide contamination already occurring in the essential oils industry using standard pesticide regimens. Oil samples from annual harvests were analysed for the presence of pesticide residues. Data from preceding years were collated to determine the progress or otherwise, in the application of best agricultural practice (BAP).2. Experimental Protocols & Detailed ResultsThe experimental conditions and results are presented under the following headings:♦Method Development♦Monitoring of Commercial Harvests♦Production of a Manual2.1 Method DevelopmentMethod development focussed on the effectiveness of clean-up techniques, validation of existing techniques, the assessment of the application of GC ECD and FPD and high pressure liquid chromatography with ion trap MS, MS detection.2.1.1 Clean-up Methodologies2.1.1.i. Application of Disposable SPE cartridges in the clean-up of pesticide residues in essentialoilsLiterature reviews provided limited information with regards to the separation of contaminants within essential oils. The retention characteristics of disposable C18 cartridges were trialed.Experiment 1;Aim : To assess the capacity of disposable C18 cartridges to the separation of boronia oil components. Experimental : Boronia concrete (49.8 mg) was dissolved in 0.5 mL of acetone and 0.4 mL of chloroform was added. 1mg of octadecane was added as an internal standard. A C18 Sep-Pak Classic cartridge (short body) was pre- conditioned with 1.25 mL of methanol, which was passed through the column at 7.5 mLmin-1, followed by 1.25 mL of acetone, at the same flow rate. The boronia samplewas then applied to the column at 2 mLmin-1 flow and eluted with 1.25 mL of acetone / chloroform (5/ 4) and then eluted with a further 2.5 mL of chloroform. 5 fractions of 25 drops each were collected. The fractions were analysed by GC FID using the following parametersAnalytical parameters6890PackardHewlettGCcolumn: Hewlett Packard 5MS 30m, i.d 0.32µmcarrier gas instrument grade nitrogeninjection volume: 1µL (split)injector temp: 250°Cdetector temp: 280°Cinital temp: 50°C (3 min), 10°Cmin-1 to 270°C (7 mins)head pressure : 10psi.Results : Table 1 record the percentage volatiles detected in the fractions collectedFraction 1 2 3 4 5 % components eluting 18 67 13 2636%monoterpenes 15%sesquiquiterpenes 33 65 2%high M.W components 1 43 47 9Table 1. Percentage volatiles eluting from SPE C18 cartridgesDiscussion : The majority of boronia components eluted on the solvent front, effecting minimal separation. This area of SPE clean-up of essential oils requires a wide ranging investigation, varying parameters such as cartridge type and polarity of mobile phase.Experiment 2.Aim : For the development of methods using LC MSMS without clean-up steps, the potential for oil components to accumulate on the reverse phase (RP) column must be assessed. The retention of essential oil components on SPE C18 cartridges, using the same mobile phase as that to be used in theLC system, would provide a good indication as to the risk of contamination of the LC columns withoil components.Experimental: Parsley oil (20-30 mg) was weighed into a GC vial. 200 µL of a 10 µgmL-1 solution (equivalent to 100mgkg-1 in oil) of each of sethoxydim, simazine, terbacil, prometryn, tebuconazoleand propiconazole were used to spike the oil, which was then dissolved in 1.0 mL of acetonitrile. The solution was then slowly introduced to the C18 cartridge (Waters Sep Pac 'classic' C18 #51910) using a disposable luer lock, 10 mL syringe, under constant manual pressure, and eluted with 9 mLs of acetonitrile. Ten, 1 mL fractions were collected and transferred to GC vials. 1mg of octadecane was added to each vial and the samples were analysed by GC FID under the conditions described in experiment 1.The experiment was repeated using C18 cartridges which had been pre-conditioned with distilled waterfor 15 mins. Again, parsley oil, spiked with pesticides was eluted with acetonitrile and 5 x 1 mL fractions collected.Results: The majority of oil components and pesticides were eluted from the C18 cartridge in the firsttwo fractions. Little to no separation of the target pesticides from the oil matrix was achieved. Table2 lists the distribution of essential oil components in the fractions collected.Fraction 1 2 3 4 5 % components eluting 18 67 13 2663%monoterpenes 15%sesquiquiterpenes 33 65 2%high M.W components 1 43 47 9water conditioned% components eluting 35 56 8 12%monoterpenes 3068%sesquiquiterpenes 60 39 1 0%high M.W components 0 50 42 7Table 2. Percentage volatiles eluting for SPE C18 cartridgesFigure 1 shows a histogram of the percentage distribution of components from the oil in each of the four fractions.Figure 1. Histogram of the percentage of volatiles of distilled oils in each of four fraction elutedon SPE C18 cartridges (non-preconditioned)Figure 2. Histogram of the percentage of volatiles of distilled oils in each of four fraction elutedon SPE C18 cartridges (preconditioned)Discussion : The chemical properties of many of the target pesticides, including polarity, solubility in organic solvents and chromatographic behaviour, are similar to the majority of essential oil components. This precludes the effective separation of analytes from such matrices through the use of standard techniques, where the major focus is pre-concentration of pesticide residues from water or water based vegetative material. However, this experiment served to provide a good indication that under HPLC conditions, where a reverse phase C18 column is used in conjunction with acetonitrile / water based mobile phases, essential oil components do not remain on the column.。

controlnet训练代码英文回答：ControlNet is a training code that is used in computer vision tasks, specifically for object detection and localization. It is designed to provide a reliable and efficient way to train deep neural networks for these tasks.One of the main advantages of ControlNet is its ability to handle large-scale datasets. It can efficiently process and train on millions of images, which is crucial for achieving state-of-the-art performance in object detection. This is especially important in applications such as autonomous driving, where the network needs to be trainedon a vast amount of diverse and representative data.ControlNet also incorporates various advancedtechniques to improve the training process. For example, it utilizes data augmentation techniques to artificially increase the size of the training dataset. This helps toprevent overfitting and improve the generalization abilityof the network. Data augmentation techniques can include random cropping, flipping, rotation, and color jittering.Additionally, ControlNet employs a multi-scale training strategy. This means that during training, the network is exposed to objects of different scales, from small to large. This helps the network learn to detect objects at various sizes and improves its robustness in real-world scenarios. For example, in the context of autonomous driving, objects can appear at different distances and scales, and the network needs to be able to accurately detect them regardless of their size.Furthermore, ControlNet utilizes a combination of different loss functions to optimize the network. One commonly used loss function is the localization loss, which penalizes the discrepancy between the predicted boundingbox and the ground truth bounding box. Another lossfunction is the classification loss, which penalizes the misclassification of objects. By combining these loss functions, ControlNet can effectively learn to localize andclassify objects simultaneously.ControlNet also incorporates transfer learning, which allows the network to leverage pre-trained models on large-scale datasets such as ImageNet. This helps to bootstrap the training process and enables the network to learn from the knowledge already acquired by the pre-trained model. Transfer learning can significantly speed up the training process and improve the final performance of the network.中文回答：ControlNet是一种用于计算机视觉任务的训练代码，特别用于目标检测和定位。

open-vocabulary object detection综述Open-vocabulary object detection refers to the task of detecting and localizing objects in images or videos without relying on a pre-defined set of object categories. In traditional object detection approaches, a fixed set of object categories is predefined, and the models are trained to classify and localize these specific categories. However, open-vocabulary object detection aims to overcome this limitation by enabling models to detect and localize objects of any category, without a predetermined list.Open-vocabulary object detection has gained attention due to its potential applications in various areas such as surveillance, autonomous driving, and robotics. It allows for the detection of novel or rare objects that were not included in the pre-defined set of categories. This flexibility enables the system to adapt to different environments and handle unforeseen or dynamically changing objects.There are several approaches to open-vocabulary object detection. One common approach is to treat object detection as an image retrieval problem. In this approach, object instances are represented by visual signatures or descriptors, such as local features or deep neural network embeddings. Given a query image, the system retrieves images from a large database that contain similar visual signatures. The retrieved images are then used to localize and detect objects.Another approach is to use object proposal methods to generate a set of candidate regions in an image. These regions are then classified into various object categories using a deep neuralnetwork. This approach leverages the power of deep learning to learn discriminative features for object detection, while still being open-vocabulary by not relying on a fixed set of categories.Open-vocabulary object detection faces several challenges. One major challenge is handling novel and rare objects. Since these objects might not have sufficient training data, the models need to be able to generalize well to unseen categories. Another challenge is dealing with large-scale datasets and retrieval tasks efficiently, as open-vocabulary object detection often requires searching through a massive amount of images or videos.In conclusion, open-vocabulary object detection is an exciting research area that aims to enable models to detect and localize objects without relying on a pre-defined set of categories. It provides flexibility and adaptability to handle novel or rare objects, making it suitable for real-world applications with dynamic object sets.。

国别环境尽调的英语Country Environmental Due DiligenceCountry environmental due diligence refers to the process of assessing the environmental risks and opportunities associated with a particular country. This assessment is done to support decision-making in various sectors such as investment, trade, and development.The purpose of country environmental due diligence is to understand the environmental context of a country, including its environmental policies, regulations, and enforcement mechanisms. It also involves evaluating the country's environmental performance, including its progress towards sustainable development goals, and identifying potential environmental risks and opportunities that may affect investments or business operations.The process typically involves gathering and analyzing data on various environmental indicators such as air and water quality, waste management, biodiversity, climate change, and natural resource management. It also involves reviewing relevant environmental laws, regulations, and policies, as well as assessing the capacity of the government and local institutions to implement and enforce these measures.This information is then used to determine the potential environmental risks and opportunities associated with investing or operating in a particular country. It helps stakeholders assess the potential impacts of their activities on the environment, identifymeasures to mitigate negative impacts, and capitalize on opportunities to contribute to sustainable development.The findings of country environmental due diligence are often presented in a report, which includes an assessment of the environmental risks and opportunities, as well as recommendations for risk management and sustainability strategies.Overall, country environmental due diligence plays a crucial role in promoting environmentally responsible investments and sustainable development by helping stakeholders make informed decisions that take into account the environmental context of a country.。

安全检测英语Security inspection is an important aspect of ensuring the safety and well-being of individuals and the community. It involves the evaluation, assessment, and monitoring of potential risks and hazards in various environments, such as public spaces, residential areas, and workplaces. The purpose of security inspection is to identify and address any vulnerabilities or weaknesses that could compromise safety and security.Security inspection includes a range of activities, such as physical inspections of buildings and facilities, surveillance of areas using CCTV cameras and other monitoring systems, and the implementation of security protocols and procedures. It also involves the assessment of potential threats, including criminal activities,natural disasters, and other emergencies, and the development of strategies to prevent and respond to these threats.Security inspection is essential for maintaining a safe and secure environment for individuals and the community.It helps to deter criminal activities, protect property andassets, and ensure the safety of people in public spaces and private facilities. By identifying and addressing security vulnerabilities, security inspection helps to minimize the risk of harm and damage and to promote a sense of safety and well-being.Security inspection is particularly important in high-risk environments, such as airports, government buildings, and critical infrastructure facilities. In these settings, security inspection plays a crucial role in preventing terrorist attacks, sabotage, and other security threats. By implementing strict security measures and conducting regular inspections, these facilities can effectively protect against potential risks and maintain the safety and security of the people and assets within their premises.In addition to physical security inspections, cybersecurity inspection is also a critical aspect of security management. With the increasing reliance ondigital technologies and online systems, the risk of cyber threats and attacks has become a major concern for organizations and individuals. Cybersecurity inspection involves the assessment of digital systems, networks, anddata to identify and address potential vulnerabilities and weaknesses that could be exploited by cybercriminals. By conducting regular cybersecurity inspections, organizations can ensure the integrity and security of their digital infrastructure and protect against cyber threats.Overall, security inspection is a fundamental componentof security management, helping to identify and address potential risks and vulnerabilities in various environments. By conducting thorough inspections and implementing appropriate security measures, organizations andindividuals can effectively protect against securitythreats and ensure the safety and well-being of people and assets.安全检测是确保个人和社区安全和福祉的重要方面。

收稿日期:2007-04-27;修回日期:2007-07-09。

作者简介:王伟嘉(1977-),女,江苏镇江人,硕士研究生,主要研究方向:运动目标检测、跟踪、智能视觉监控等;　刘辉(1969-),男,云南昆明人,教授,主要研究方向:图像处理及模式识别;　沙莉(1975-),女,天津人,讲师,主要研究方向:图像处理;　刘鑫(1981-),男,湖南冷水江人,硕士研究生,主要研究方向:运动目标的检测、跟踪、智能视觉监控等;　姜华(1982-),女,四川江油人,硕士研究生,主要研究方向:运动目标的检测、跟踪、智能视觉监控等。

文章编号:1001-9081(2007)10-2591-04滞留与偷窃物体实时检测与分类算法王伟嘉1,刘　辉1,沙　莉2,刘　鑫1,姜　华1(1.昆明理工大学信息工程与自动化学院,昆明650051;2.云南财经大学信息学院,昆明650221)(wwjia123@yahoo :)摘　要:研究了在静止的单摄像机条件下滞留与偷窃物体检测与分类算法。

基于轮廓的判别方法在环境轮廓复杂情况下检测率会降低。

在吸收了原有轮廓空间相似性算法的基础上,加入了轮廓的连通性判断,只有轮廓同时满足空间和连通性都相似的物体才被判定为滞留物体。

此外还研究了基于颜色直方图的巴氏距离的判定方法,将以上两种方法进行了比较。

实验结果表明,在现实环境下,改进后的轮廓判别方法比颜色方法适应性更强,检测正确率更高。

关键词:运动目标检测;行为理解;滞留和偷窃物中图分类号:TP391.4 文献标志码:ARea l ti m e detecti on and cl a ssi f i ca ti on a lgor ith m for abandoned and stolen objectsWANG W ei 2jia 1,L I U Hui 1,SHA L i 2,L I U Xin 1,J I A NG Hua1(1.school of Infor m ation Engineering and A uto m ation,Kunm ing U niversity of Science and Technology,Kunm ing Yunnan 650051,China ;r m ation Institute,Yunnan U niversity of Finance and Econo m ics,Kunm ing Yunnan 650221,China )Abstract:A lgorith m for real ti m e abandoned /st olen objects detecti on by a single and static ca mera was studied .Itintended t o s olve the p r oble m that the detecti on validity of gradient 2based method will decrease under the conditi on that the gradient of envir on ment is comp lex .Besides the edge points πpositi on analysis of cont our,the edge points πconnectivity analysis of cont our was intr oduced .Only the object of which the cont our reaches the si m ilarity of both the edge points πpositi on and connectivity can be recognized as the abandoned object .I n additi on,H ist ogra m 2based method which calculates and compares the Bhattacharya distance bet w een hist ogra m s t o deter m ine if the object is abandoned or st olen was studied,and was compared with the first method .Experi m ental results show that the i m p r oved gradient 2based method is more adap table and effective .Key words:moving object detecti on;activity recogniti on;abandoned and st olen objects0　引言滞留物体与偷窃物体的检测与分类算法主要利用图像处理和分析的方法,在现实场景中自动检测静态物体,提取物体信息(颜色、轨迹、轮廓),实时和准确的识别物体滞留或物体偷窃事件的发生,报警和抓取证据图片和视频,使计算机具有某种理解和分析视频能力,从而对危险事件具有主动监测、防范和预警的功能。

Views and ReviewsPractice Standards for Transcranial Doppler (TCD)Ultrasound.Part II.Clinical Indications and Expected OutcomesAndrei V.Alexandrov,MD,Michael A.Sloan,MD,Charles H.Tegeler,MD,David N.Newell,MD,Alan Lumsden,MD,Zsolt Garami,MD,Christopher R.Levy,MD,Lawrence K.S.Wong,MD,Colleen Douville,RVT,Manfred Kaps,MD,Georgios Tsivgoulis,MD,PhD;for the American Society of Neuroimaging Practice Guidelines CommitteeFrom the Comprehensive Stroke Center,University of Alabama at Birmingham,Birmingham,AL (AVA,GT);Comprehensive Stroke Center,University of South Florida,Tampa,FL (MAS);Stroke Program,Wake Forest University Medical Center,Winston-Salem,NC (CHT);Department of Neurosurgery,Swedish Hospital,Seattle,WA (DNN,CD);Department of Cardio-Thoracic Surgery,Cornell University and The Methodist Hospital Houston,TX (AL,ZG);Hunter Stroke Service,Hunter New England Area Health Service,New South Wales,Australia (CRL);Division of Neurology,Chinese University of Hong Kong,Hong Kong,China (LKSW);Department of Neurology,University of Giessen,Giessen,Germany (MK);Department of Neurology,Democritus University of Thrace,Alexandroupolis,Greece (GT).Keywords:TCD,indications,applica-tions and outcomes.Acceptance:Received May 23,2010,and in revised form July 06,2010.Ac-cepted for publication July 15,2010.Correspondence:Address correspon-dence to Dr.Andrei V .Alexandrov,Com-prehensive Stroke Center/Neurology,The University of Alabama at Birming-ham,RWUH M226,61919th St South,Birmingham,AL 35249-3280.E-mail:avalexandrov@.J Neuroimaging 2010;XX:1-10.DOI:10.1111/j.1552-6569.2010.00523.xA B S T R A C TINTRODUCTIONTranscranial Doppler (TCD)is a physiological ultrasound test with established safety and efficacy.Although imaging devices may be used to depict intracranial flow superimposed on structural visualization,the end-result provided by imaging duplex or nonimaging TCD is sampling physiological flow variables through the spectral waveform assessment.SUMMARY OF RESULTSClinical indications considered by this multidisciplinary panel of experts as established are:sickle cell disease,cerebral ischemia,detection of right-to-left shunts (RLS),sub-arachnoid hemorrhage,brain death,and periprocedural or surgical monitoring.The follow-ing TCD-procedures are performed in routine in-and outpatient clinical practice:complete or partial TCD-examination to detect normal,stenosed,or occluded intracranial vessels,collaterals to locate an arterial obstruction and refine carotid-duplex or noninvasive angio-graphic findings;vasomotor reactivity testing to identify high-risk patients for first-ever or recurrent stroke;emboli detection to detect,localize,and quantify cerebral emboliza-tion in real time;RLS-detection in patients with suspected paradoxical embolism or those considered for shunt closure;monitoring of thrombolysis to facilitate recanalization and detect reocclusion;monitoring of endovascular stenting,carotid endarterectomy,and car-diac surgery to detect perioperative embolism,thrombosis,hypo-and hyperperfusion.CONCLUSIONBy defining the scope of practice,these standards will assist referring and reporting physicians and third parties involved in the process of requesting,evaluating,and acting upon TCD results.IntroductionFrom the stand-point of ultrasound physics,transcranial Doppler (TCD)was invented 1as one of the simplest tests based on a single-element transducer technology.Clinically,however,TCD is perhaps the most complex physiological test in vascu-lar medicine requiring in-depth skill training and understanding of cerebrovascular anatomy,physiology,and a variety of clin-ically diverse pathological conditions.Regardless of whether imaging duplex ultrasound or nonimaging TCD system is used for intracranial flow assessment,the end-product is the spec-tral waveform analysis and determination of physiological flow variables.Hemodynamic changes within normal and abnormal states present a complex task of correct sampling,monitoring,and interpretation even for experienced users across multiple clinical conditions.These are some of the reasons why so few people mastered this technique over the past quarter of a cen-tury and so many still remain skeptical.Nevertheless,tremen-dous progress has been made to establish certain areas where TCD is beyond doubt a valid and reliable diagnostic test that provides unique information,complimentary and often unob-tainable from other modalities,with its own prognostic and therapeutic significance.This multispecialty panel of experts convened by the Clinical Practice Committee of the American Society of Neuroimaging set the goal to define clinical indi-cations for and expected outcomes of TCD testing in routine clinical practice.With advances in stroke diagnosis,treatment,and pre-vention,TCD became the standard of care at comprehen-sive stroke centers being one of the essential diagnostic tests and services that a modern stroke team should have at theirCopyright◦C2010by the American Society of Neuroimaging1Table1.Diagnostic Test Performance Parameters Documented for TCDParameter Areas covered by published studiesApplicability Feasibility,tolerability,and success in consecutive patients:TCD is successfully applied to90%of patients withcerebrovascular diseases with no reports of adverse outcomes in26years of research and practice worldwide. Accuracy Comparison with DSA/MRA/CTA as well as other clinically relevant studies or outcomes:TCD has good-to-excellent agreement with angiography for the detection of stenoses and occlusions;equal to superior accuracy in the detection ofRLS versus TEE;and excellent agreement with nuclear flow studies in determining cerebral circulatory arrest.Yield Disease states which diagnosis with TCD was documented in research studies involving the gold standard imaging or clinical assessment range from intracranial stenoocclusive disease,collaterals to cerebral embolization,shunting,vasomotor reactivity,vasospasm after SAH,periprocedural and surgical monitoring,and cerebral circulatory arrest. Prognosis TCD has the ability to select children with sickle cell disease in need of blood transfusion and who should stay on blood transfusion to sustain the benefit for primary stroke prevention;to predict outcomes of thrombolytic therapy for acutestroke;to identify high-risk patients that will require interventions to reverse or prevent stroke and to provide lessexpensive follow-up assessments.TCD=Transcranial Doppler,DSA=digital subtraction angiography;CTA=CT angiography;MRA=MR angiography;TEE=transesophageal echocardiography; RLS=right-to-left shunt;SAH=subarachnoid hemorrhage.disposal.2Whether one’s practice is hospital or office-based, TCD offers a low-cost diagnostic method to find high-risk patients for first-ever,recurrent stroke or stroke progression caused by intracranial steal phenomenon(reversed Robin Hood syndrome),identify stroke pathogenic mechanism,re-fine results of widely used imaging tests such as carotid du-plex or noninvasive angiography,detect right-to-left shunts (RLS),and perform limited follow-up studies to avoid rep-etition of more expensive or invasive tests.3-5Furthermore, with advances in vascular interventions and cardiac surgery, TCD monitoring is now recognized as a practical tool to de-tect intra-and periprocedural events and prevent untoward outcomes.3-5Specific Clinical IndicationsOur multidisciplinary panel of experts reviewed the published literature on TCD from1982through December2009in their respective fields,including previous updates6-9and considered reported clinical indications as established if TCD performance has been tested in terms of applicability,yield,accuracy,and prognosis including outcomes(broadly defined as proven diag-nostic value in a specific clinical situation,therapeutic implica-tions of test results,identification of high-risk patients,detection of periprocedural complication mechanism,ie,when informa-tion derived from TCD impacted clinical decision making and the choice of management options).These criteria and review of areas that were evaluated in research studies are presented in Table1.Specific established clinical indications for TCD in routine clinical practice that met our criteria include:sickle cell dis-ease,cerebral ischemia(stroke,transient ischemic attack;TIA), carotid artery stenosis and occlusions,vasospasm after sub-arachnoid hemorrhage(SAH),brain death,and periprocedural or surgical monitoring.For evaluating the quality of evidence and strength of recommendations for these specific clinical in-dications we used the“Format for an Assessment”(Table2)de-veloped by the American Academy of Neurology(for example, the assessment of clinical indications of single-photon emission computed tomography)10and used in a previous update of the American Society of Neuroimaging on TCD indications.8De-tails of these clinical indications and expected outcomes derived from published studies are presented in Table3.Sickle Cell DiseaseTCD can identify children with the highest risk of first-ever stroke10and those in need of blood transfusion[Quality of evidence:class I;Strength of recommendation:type A].11In a pivotal trial,11TCD detection of time averaged maximum mean flow velocity of200cm/s on2separate examinations was used to determine the need for blood transfusion that re-sulted in90%relative risk reduction of first-ever stroke.ThisTable2.Quality of Evidence and Strength of Recommendation Ratings According to the“Format for an Assessment”Developed by the American Academy of Neurology4and Adopted by the American Society of Neuroimaging10RatingsQuality of EvidenceClass I Evidence provided by one or more well-designed,randomized controlled clinical trialClass II Evidence provided by one or more well-designed,clinical studies(eg,case control,cohort studies)Class III Evidence provided by one or more expert opinions,nonrandomized historic controls,or case reportsStrength of RecommendationType A Strong positive recommendation,based on class I evidence or overwhelming class II evidence when circumstances preclude randomized clinical trialsType B Positive recommendation,based on class II evidenceType C Positive recommendation,based on strong consensus of class III evidenceType D Negative recommendation,based on inconclusive or conflicting class II evidenceType E Negative recommendation,based on evidence of ineffectiveness or lack of efficacy,based on class II or class I evidence2Journal of Neuroimaging Vol XX No XX2010Table3.Established Clinical Indications for and Expected Outcomes of TCD TestingBroad Indication Specific Indications Expected OutcomesSickle cell anemia Children Robust first-ever stroke risk reduction based on TCD criteria for the need ofblood transfusion and continuing use of blood transfusions.Ischemic Stroke or TIA Patients with acute ischemicsymptoms in anterior orposterior circulation whohad cranial CT or MRI TCD can identify patients with proximal arterial occlusions both in anterior and posterior circulation who have the worst prognosis and can benefit the most from intravenous thrombolysis or rescue intraarterial therapies.Ischemic stroke or TIA Patients with subacuteischemic symptoms inanterior or posteriorcirculation who hadcranial CT or MRI TCD helps determine stroke pathogenic mechanism that in turn determines secondary stroke prevention treatment,ie,antiplatelets versus anticoagulation versus stenting versus carotid endarterectomy or systemic hemodynamics manipulation in cases of stenoocclusive disease with hemodynamic compromise.TCD also helps to localize and grade intracranial atheromatous disease process,(anterior vs.posterior vessels,diffuse vs.local disease,≥70% stenoses that indicate high risk of stroke recurrence).Ischemic stroke or TIA Symptomatic patient at anytime window whounderwent carotidduplex scanning Carotid duplex ultrasound may explain only15-25%of all ischemic events since the prevalence of≥50%proximal ICA stenosis is low.TCD has the ability to further refine stroke mechanism detection by determining the presence of intracranial stenoocclusive disease,embolization,shunting,and impaired vasomotor reactivity(VMR).Ischemic stroke or TIA Patients with undeterminedstroke mechanism,recurrent TIAs,artery-to-artery versuscardiac source ofembolism,suspectedarterial dissections TCD is the gold standard test to detect,localize,and quantify cerebral embolism in real time.No other modality offers spatial and time resolution to detect microembolic activity,localize its source(artery vs.heart),and confirm vascular etiology of patient symptoms.Ischemic stroke or TIA Patients with suspectedparadoxical embolismwith negativeechocardiography TCD is equal or superior in its sensitivity to the presence of any right-to-left shunt compared to echocardiography(Valsavla maneuver is best accomplished during TCD,extracardiac shunting can be indirectly detected with TCD).Ischemic stroke or TIA Follow-up TCD is an inexpensive noninvasive follow-up tool that can detect progression orregression in the severity of extra-and intracranial stenoses through directvelocity measurements,collaterals,and VMR assessment.Asymptomatic or symptomatic carotid artery stenosis or occlusion Patients who have theinternal carotid artery(ICA)stenosis orocclusion on carotidduplex or angiographyTCD can help identify patients at highest risk of first-ever or recurrent stroke inthe setting of an ICA stenosis of variable degree or complete occlusion.TCDfindings of artery-to-artery embolization and impaired vasomotor reactivityindicate3-4-fold higher risk of stroke compared to patients with similar degreeof ICA stenosis and normal TCD findings.Subarachnoid hemorrhage Days2-5TCD can detect the development of vasospasm days before it can becomeclinically apparent,and this information can be used by intensivists to step upwith hemodynamic management of these patients.Days5-12TCD can detect progression to the severe phase of spasm when development ofthe delayed ischemic deficit due to perfusion failure through the residuallumen is the greatest.This information can help planning interventions(angioplasty,nicardipine infusions).Days12-end of ICU stay TCD can document spasm resolution after treatment or intervention,sustainability of vessel patency,and infrequent cases of late or reboundvasospasm development at the end of the second or into the third week aftersubarachnoid hemorrhage.Suspected brain death Increased intracranialpressure,mass effect,herniation TCD can rule out cerebral circulatory arrest if positive diastolic flow is detected at any ICP values.TCD can confirm clinical diagnosis of brain death by demonstrating complete cerebral circulatory arrest in anterior and posterior circulation.TCD offers serial noninvasive assessments and can minimize the number of nuclear flow studies needed to confirm the arrest of cerebral circulation.Periprocedural or surgical monitoring Carotid endarterectomy orstentingTCD can detect all major causes of perioperative complications,ie,embolism,thrombosis,hypoperfusion,and hyperperfusion.TCD detects real-time flowchanges that precede the development of neurological deficits or changes onelectroencephalography.Cardiovascular surgical monitoring CABG,repairs of ascendingaortaTCD can detect cerebral embolization and hypoperfusion.TCD can help guideperfusion pump settings as well as cannulation and body positioning TCD canidentify unsuspected causes of massive air embolization and guide surgeons toexplore sites of possible arterial puncture.Alexandrov et al:TCD Indications and Expected Outcomes3trial demonstrated that TCD can select patients for the most ef-fective primary stroke prevention intervention to date that had profound implications on management of children with sickle cell disease.Further observations confirmed that children ini-tially selected by TCD for blood transfusion should stay on transfusion schedule to sustain the benefit in stroke risk reduc-tion.12Moreover,recent data including long-term follow-up and final results from the Stroke Prevention Trial in Sickle Cell Anemia(STOP)indicated that persistent elevation in TCD ve-locities indicates ongoing stroke risk.13The skill of TCD testing in children with sickle cell anemia is taught through standard tutorials with sonographers receiving specialized certificates, and diagnostic criteria for interpreting physicians are well de-fined.14,15Subarachnoid HemorrhageNumerous studies have shown the effectiveness of TCD in di-agnosing cerebral vasospam both in anterior and posterior cir-culation following SAH[Quality of evidence:class II;Strength of recommendation:type B].16-24More specifically,TCD can detect the development of vasospasm days before it can be-come clinically apparent(days2–5following SAH onset),and this information can be used by intensivists to step up with hemodynamic management of these patients.8,25In addition, TCD can detect progression to the severe phase of spasm when development of the delayed ischemic deficit due to perfusion failure through the residual lumen is the greatest.The maximal sensitivity of TCD for detecting cerebral vasospasm is at8days after SAH onset,while its sensitivity for diagnosing delayed cerebral ischemia is lower(63%).25Also,a recent study has demonstrated the predictive superiority of TCD over single-photon emission computer tomography for the diagnosis of an-giographically demonstrated cerebral vasospasm.23Moreover, Sloan and colleagues showed that TCD is highly specific(100%) for vertebral and basilar artery vasospasm when mean flow ve-locities are≥80and≥95cm/s,respectively.24Another inde-pendent study showed that patients with very high basilar artery mean flow velocities(>115cm/s)had a50%chance of develop-ing delayed brainstem ischemia,which in turn was associated with adverse functional outcome.21Therefore,TCD informa-tion can help planning interventions including angioplasty and nicardipine infusions.Based upon the available evidence,the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology has recently stated that TCD is useful for the detection of vasospasm following spontaneous SAH.25Cerebral IschemiaAcute Cerebral IschemiaWith over1,700papers published as of December2009,this subject is one of the most studied among TCD applications. An indication“ischemic stroke”or“transient ischemic attack”may necessitate not only a complete diagnostic examination in order to detect the presence of stenoocclusive disease[Quality of evidence:class II;Strength of recommendation:type B],as outlined in our previous standards,8,26but also include vaso-motor reactivity assessment,emboli detection,RLS testing as well as continuous real-time intracranial vessel monitoring.We in turn examine specific indications for these TCD tests.The reasons to perform TCD in patients with suspected or confirmed cerebral ischemia are plete or partial TCD examination evaluates up to16proximal intracranial ar-terial segments26,27with the goal of detecting normal,stenosed, or occluded intracranial vessels.Vessel patency has prognostic significance as patients with persisting occlusions have worse outcomes if reperfusion therapy is not instituted timely or is ineffective.26-28This information is also helpful to select pa-tients for catheter angiography,intraarterial rescue(interven-tional devices for clot removal),29and potentially hemicraniec-tomy(surgical decompression to save lives after severe ischemic stroke).TCD evaluation also has diagnostic significance to identify stroke pathogenic mechanism,ie,large-vessel stenosis of≥50%, or artery-to-artery embolism as opposed to a cardiac or para-doxical embolism source.Patients with intracranial disease are at high(10–15%annually)risk of stroke recurrence if only as-pirin for secondary prevention is considered.30New treatment strategies including statins,selective anticoagulation,and stent-ing are being used in patients with high-grade stenoses refrac-tory to standard antiplatelet therapy.31,32The same TCD examination can detect collateral flow and the hemodynamic significance of extracranial or intracranial stenoocclusive lesions[Quality of evidence:class II;Strength of recommendation:type B].33-41This information is helpful to identify a proximal arterial obstruction and to clarify carotid duplex or noninvasive angiographic findings including MR-angiography(MRA)and CT-angiography(CTA).Carotid du-plex and MRA are known to produce falsely elevated esti-mates of the degree of carotid stenosis and TCD,via collateral and downstream hemodynamic effects,can help clarify false-negative and false-positive diagnosis of severe ICA stenosis.A severe ICA stenosis should produce downstream flow changes directly detectable by TCD,and if no delay in systolic flow ac-celeration is seen or no collaterals are detected,these TCD find-ings likely indicate moderate proximal ICA stenosis.27,33,38On the other hand,if extracranial duplex scanning could not reveal a severe ICA lesion(eg,high carotid bifurcation),the presence of unilaterally delayed systolic flow acceleration or intracranial collaterals would suggest the presence of a severe proximal ICA lesion.27,33,38For intracranial stenoocclusive lesions,intracra-nial MRA often shows flow gaps due to turbulence or reversal of flow direction,thus overestimating the degree of stenosis.TCD findings of focal elevated velocities confirm the presence of an intracranial stenosis or collaterals when applicable,and vali-dated diagnostic criteria are available.27,42More specifically,2 recent studies have validated the diagnostic accuracy of TCD against CTA for evaluating arterial stenoocclusive disease in the setting of acute(24hours)cerebral ischemia.38,39In both stud-ies,bedside TCD examination yielded satisfactory agreement (sensitivity>75%,specificity>90%)with urgent brain CTA, while it should be noted that in both studies sonographers were blinded to the results of CTA,which in the majority of cases was performed following TCD evaluation.The yield of standard TCD vessel surveillance(stenoses,oc-clusions,collaterals,and lesions amenable to intervention)is4Journal of Neuroimaging Vol XX No XX2010substantial if performed alone40or in combination with carotid duplex ultrasound41particularly in patients with acute cerebral ischemia or TIAs.Identification of patients with proximal ar-terial occlusions has prognostic information,helps determine stroke pathogenic mechanism,and individualize early manage-ment of a stroke or TIA patient in addition to information pro-vided by brain CT or MRI.40,41It is therefore recommended to perform TCD studies always in conjunction with ultrasound examination of the extracranial brain supplying arteries.Fur-thermore,residual flow at the site of acute intracranial occlu-sion predicts response to intravenous thrombolysis according to findings of2independent multicenter studies.43,44More specif-ically,the finding of no detectable residual flow indicates the least chance to achieve recanalization and recovery with sys-temic thrombolysis and may support an early decision for com-bined endovascular rescue.43The yield of TCD is greatest the closer in time it is performed to stroke symptom onset40and is higher in anterior than in posterior circulation.26,27,42More specifically,the recently pub-lished recommendations of the American Heart Association for imaging of acute stroke underline that the sensitivity and speci-ficity of TCD for the anterior circulation range from70%to90% and90-95%compared to DSA,while the same accuracy pa-rameters for the posterior circulation are lower(sensitivity:50-80%,specificity:80-96%).42Notably,the use of power-motion mode TCD(PMD-TCD)or transcranial color-coded duplex (TCCD)increases the diagnostic accuracy of neurosonology for the assessment of vertebrobasilar circulation.35,45PMD, B-Mode or color-flow display can depict Doppler signatures that are complimentary to and can increase confidence in stan-dard single-gate spectral findings.More specifically,in a recent study evaluating the diagnostic yield of TCD against CTA in the acute setting of cerebral ischemia(<48hours)the investi-gators reported that PMD-TCD contributed information com-plementary to CTA(real-time embolization,collateralization of flow with extracranial internal carotid artery disease,alter-nating flow signals indicative of steal phenomenon)in7%of the studied patients.38Similar findings have been reproduced during the separate evaluation of the posterior circulation with PMD-TCD.35Recommendations regarding the potential appli-cability of TCCD in the setting of acute arterial ischemia have recently been introduced by an international consensus panel of35experts.46Intracranial Arterial Disease(IAD)TCD can reliably rule out intracranial stenosis according to the findings of the recently published Stroke Outcomes and Neu-roimaging of Intracranial Atherosclerosis(SONIA)trial,which aimed to define the positive and negative predictive value(PPV and NPV)of TCD/MRA for the identification of50%to99% intracranial stenosis in the intracranial ICA,MCA(middle cere-bral artery),VA(vertebral artery),and BA(basilar artery).47 SONIA standardized the performance and interpretation of TCD,MRA,CTA(when available)and catheter-based angiog-raphy using study-wide cutpoints defining positive findings. Hard copy TCD/MRA studies were centrally read,blinded to the results of catheter-based angiography(gold standard). The trial showed that TCD and MRA can reliably exclude the presence of intracranial stenosis(NPV=86%,95%CI81-89%). However,abnormal findings on TCD or MRA require a con-firmatory test such as angiography to reliably identify stenosis (PPV=36%,95%CI27-46%).However,it should be noted that SONIA findings were based on a limited number of ves-sels evaluated by TCD(n=451)compared to MRA(n=1310), while TCD abnormalities associated with occlusion on angiog-raphy(despite the fact that they represented severe intracranial disease)were considered false positives because an occlusion was not treated with a stent.This approach resulted in SONIA increasing NPV but decreasing PPV.A multicenter prospective study48was recently performed to determine if SONIA criteria,and TCD can be reliably used between different laboratories that have standardized scanning protocols according to our criteria.26Consecutive patients with symptoms of cerebral ischemia evaluated by TCD and catheter angiography at3tertiary care centers were prospectively stud-ied.Baseline stroke severity(NIHSS)was documented.TCD measurements of peak systolic(PSV),end-diastolic(EDV),and mean flow(MFV)velocities were performed.The following MFV cut-offs were used for the identification of≥50%steno-sis using published SONIA criteria:MFV MCA>100cm/s, TICA/ACA>90cm/s,VA/BA/PCA>80cm/s,and deter-mined velocity cut-offs for the≥70%stenosis on angiography. The study also evaluated whether the addition of stenotic to prestenotic ratio(SPR)would increase the accuracy of velocity prediction of IAD with≥70%stenosis.Among a total of172patients with DSA/TCD data,33 had confirmed IAD(age54±13yrs;70%men;50%Cau-casian,18%African-American,32%Asian;median NIHSS3, interquartile range6)providing375TCD/DSA measurement pairs for comparison.On DSA,≥50%stenoses were located in56vessels:M1MCA(48%),M2(4%),TICA(16%),ACA (7%),VA(14%),BA(9%),PCA(2%).IAD>70%on DSA was found in21arteries(anterior circulation18,posterior circula-tion3).The accuracy parameters of TCD(SONIA MFV cut-offs)against DSA for≥50%stenosis were as follows:sensitivity (89%),specificity(99%),PPV(93%),NPV(98%),overall accu-racy(97%)[54true positive,310true negative,4false positive, and7false negatives].The predictive ability of PSV and MFV for the detection of IAD on DSA did not differ(P>.9)both in anterior(middle cerebral artery,anterior cerebral artery,and terminal internal carotid artery)and posterior circulation(ver-tebral artery,basilar artery,and posterior circulation artery). The optimal PSV cut-off for the detection of≥70%IAD was >196cm/s(sensitivity78%,specificity95%)and>166cm/s (sensitivity100%and specificity97%)in anterior and posterior circulation,respectively.The optimal MFV cut-off for the detec-tion of≥70%IAD was>128cm/s(sensitivity78%,specificity 96%)and>119cm/s(sensitivity100%and specificity99%)in anterior and posterior circulation,respectively.The addition of an MFV SPR>3in the MFV criteria(>128cm/s in ante-rior and>119cm/s in posterior circulation increased the TCD accuracy for detecting>70%IAD(sensitivity90%,specificity 95%).48Investigators concluded that at laboratories with a standard-ized scanning protocol,SONIA MFV criteria remain reliably predictive of≥50%stenosis.The new velocity/ratio criteria forAlexandrov et al:TCD Indications and Expected Outcomes5。

Designation:D93−13´1Designation:34/99Standard Test Methods forFlash Point by Pensky-Martens Closed Cup Tester1This standard is issued under thefixed designation D93;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(´)indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.ε1NOTE—Editorially revised15.1in February2014.INTRODUCTIONThisflash point test method is a dynamic test method which depends on specified rates of heating to be able to meet the precision of the test method.The rate of heating may not in all cases give the precision quoted in the test method because of the low thermal conductivity of some materials.There areflash point test methods with slower heating rates available,such as Test Method D3941(for paints,resins,and related products,and high viscosity products in the range of0to110°C),where the test conditions are closer to equilibrium.Flash point values are a function of the apparatus design,the condition of the apparatus used,and the operational procedure carried out.Flash point can therefore only be defined in terms of a standard test method,and no general valid correlation can be guaranteed between results obtained by different test methods,or with test apparatus different from that specified.1.Scope*1.1These test methods cover the determination of theflash point of petroleum products in the temperature range from40 to370°C by a manual Pensky-Martens closed-cup apparatus or an automated Pensky-Martens closed-cup apparatus,and the determination of theflash point of biodiesel in the temperature range of60to190°C by an automated Pensky-Martens closed cup apparatus.N OTE1—Flash point determinations above250°C can be performed, however,the precision has not been determined above this temperature. For residual fuels,precision has not been determined forflash points above100°C.The precision of in-use lubricating oils has not been determined.Some specifications state a D93minimumflash point below 40°C,however,the precision has not been determined below this temperature.1.2Procedure A is applicable to distillate fuels(diesel, biodiesel blends,kerosine,heating oil,turbine fuels),new and in-use lubricating oils,and other homogeneous petroleum liquids not included in the scope of Procedure B or Procedure C.1.3Procedure B is applicable to residual fuel oils,cutback residua,used lubricating oils,mixtures of petroleum liquids with solids,petroleum liquids that tend to form a surfacefilm under test conditions,or are petroleum liquids of such kine-matic viscosity that they are not uniformly heated under the stirring and heating conditions of Procedure A.1.4Procedure C is applicable to biodiesel(B100).Since a flash point of residual alcohol in biodiesel is difficult to observe by manualflash point techniques,automated apparatus with electronicflash point detection have been found suitable. 1.5These test methods are applicable for the detection of contamination of relatively nonvolatile or nonflammable ma-terials with volatile orflammable materials.1.6The values stated in SI units are to be regarded as the standard.The values given in parentheses are for information only.N OTE2—It has been common practice inflash point standards for many decades to alternately use a C–scale or an F–scale thermometer for temperature measurement.Although the scales are close in increments, they are not equivalent.Because the F–scale thermometer used in this procedure is graduated in5°increments,it is not possible to read it to the 2°C equivalent increment of 3.6°F.Therefore,for the purposes of application of the procedure of the test method for the separate tempera-ture scale thermometers,different increments must be used.In this test method,the following protocol has been adopted:When a temperature is intended to be a converted equivalent,it will appear in parentheses following the SI unit,for example370°C(698°F).When a temperature is1These test methods are under the joint jurisdiction of ASTM Committee D02onPetroleum Products,Liquid Fuels,and Lubricants and are the direct responsibilityof Subcommittee D02.08on V olatility.In the IP,these test methods are under thejurisdiction of the Standardization Committee.Current edition approved July15,2013.Published August2013.Originallyapproved st previous edition approved in2012as D93–12.DOI:10.1520/D0093-13E01.*A Summary of Changes section appears at the end of this standard Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959.United States --` , , ` ` , , ` , ` ` , , ` , ` , , ` , , , , ` , ` ` , ` -` -` , , ` , , ` , ` , , ` ---intended to be a rationalized unit for the alternate scale,it will appear after “or,”for example,2°C or5°F.1.7This standard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specific warning statements,see6.4,7.1,9.3,9.4,11.1.2,11.1.4,11.1.8, 11.2.2,and12.1.2.2.Referenced Documents2.1ASTM Standards:2D56Test Method for Flash Point by Tag Closed Cup Tester D3941Test Method for Flash Point by the Equilibrium Method With a Closed-Cup ApparatusD4057Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177Practice for Automatic Sampling of Petroleum and Petroleum ProductsE1Specification for ASTM Liquid-in-Glass Thermometers E300Practice for Sampling Industrial ChemicalsE502Test Method for Selection and Use of ASTM Stan-dards for the Determination of Flash Point of Chemicals by Closed Cup Methods2.2ISO Standards3Guide34Quality Systems Guidelines for the Production of Reference MaterialsGuide35Certification of Reference Material—General and Statistical Principles3.Terminology3.1Definitions:3.1.1biodiesel,n—a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats,designated B100.3.1.2biodiesel blends,n—a blend of biodiesel fuel with petroleum-based diesel fuel.3.1.3dynamic,adj—in petroleum products—in petroleum productflash point test methods—the condition where the vapor above the test specimen and the test specimen are not in temperature equilibrium at the time that the ignition source is applied.3.1.3.1Discussion—This is primarily caused by the heating of the test specimen at the constant prescribed rate with the vapor temperature lagging behind the test specimen tempera-ture.3.1.4equilibrium,n—in petroleum products—in petroleum productflash point test methods—the condition where the vapor above the test specimen and the test specimen are at the same temperature at the time the ignition source is applied.3.1.4.1Discussion—This condition may not be fully achieved in practice,since the temperature may not be uniform throughout the test specimen,and the test cover and shutter on the apparatus can be cooler.3.1.5flash point,n—in petroleum products,the lowest temperature corrected to a barometric pressure of101.3kPa (760mm Hg),at which application of an ignition source causes the vapors of a specimen of the sample to ignite under specified conditions of test.4.Summary of Test Method4.1A brass test cup of specified dimensions,filled to the inside mark with test specimen andfitted with a cover of specified dimensions,is heated and the specimen stirred at specified rates,using one of three defined procedures(A,B,or C).An ignition source is directed into the test cup at regular intervals with simultaneous interruption of the stirring,until a flash is detected(see11.1.8).Theflash point is reported as defined in3.1.5.5.Significance and Use5.1Theflash point temperature is one measure of the tendency of the test specimen to form aflammable mixture with air under controlled laboratory conditions.It is only one of a number of properties which must be considered in assessing the overallflammability hazard of a material.5.2Flash point is used in shipping and safety regulations to defineflammable and combustible materials.One should con-sult the particular regulation involved for precise definitions of these classifications.N OTE3—The U.S.Department of Transportation(DOT)4and U.S. Department of Labor(OSHA)have established that liquids with aflash point under37.8°C(100°F)(see Note1)areflammable,as determined by these test methods,for those liquids which have a kinematic viscosity of 5.8mm2/s(cSt)or more at37.8°C or9.5mm2/s(cSt)or more at25°C (77°F),or that contain suspended solids,or have a tendency to form a surfacefilm while under test.Other classificationflash points have been established by these departments for liquids using these test methods. 5.3These test methods should be used to measure and describe the properties of materials,products,or assemblies in response to heat and an ignition source under controlled laboratory conditions and should not be used to describe or appraise thefire hazard orfire risk of materials,products,or assemblies under actualfire conditions.However,results of these test methods may be used as elements of afire risk assessment which takes into account all of the factors which are pertinent to an assessment of thefire hazard of a particular end use.5.4These test methods provide the only closed cupflash point test procedures for temperatures up to370°C(698°F).2For referenced ASTM standards,visit the ASTM website,,orcontact ASTM Customer Service at service@.For Annual Book of ASTM Standards volume information,refer to the standard’s Document Summary page on the ASTM website.3Available from American National Standards Institute(ANSI),25W.43rd St., 4th Floor,New York,NY10036.4For information on U.S.Department of Transportation regulations,see Codes of U.S.Regulations49CFR Chapter1and the U.S.Department of Labor,see29 CFR Chapter XVII.Each of these items is revised annually and may be procured from the Superintendent of Documents,Government Printing Office,Washington, DC20402.--` , , ` ` , , ` , ` ` , , ` , ` , , ` , , , , ` , ` ` , ` -` -` , , ` , , ` , ` , , ` ---6.Apparatus6.1Pensky-Martens Closed Cup Apparatus (manual)—This apparatus consists of the test cup,test cover and shutter,stirring device,heating source,ignition source device,air bath,and top plate described in detail in Annex A1.The assembled manual apparatus,test cup,test cup cover,and test cup assembly are illustrated in Figs.A1.1-A1.4,respectively.Di-mensions are listed respectively.6.2Pensky-Martens Closed Cup Apparatus (Automated)5—This apparatus is an automated flash point instrument that is capable of performing the test in accordance with Section 11(Procedure A),Section 12(Procedure B),and 13(Procedure C)of these test methods.The apparatus shall use the test cup,test cover and shutter,stirring device,heating source,and ignition source device described in detail in Annex A1.6.3Temperature Measuring Device—Thermometer having a range as shown as follows and conforming to the require-ments prescribed in Specification E1or in Annex A3,or an electronic temperature measuring device,such as resistance thermometers or thermocouples.The device shall exhibit the same temperature response as the mercury thermometers.Thermometer Number Temperature RangeASTM IP −5to +110°C (20to 230°F)9C (9F)15C +10to 200°C (50to 392°F)88C (88F)101C +90to 370°C (200to 700°F)10C (10F)16C6.4Ignition Source—Natural gas flame,bottled gas flame,and electric ignitors (hot wire)have been found acceptable for use as the ignition source.The gas flame device described in detailed in Fig.A1.4requires the use of the pilot flame described in A1.1.2.3.The electric ignitors shall be of the hot-wire type and shall position the heated section of the ignitor in the aperture of the test cover in the same manner as the gas flame device.(Warning—Gas pressure supplied to the apparatus should not be allowed to exceed 3kPa (12in.)of water pressure.)6.5Barometer—With accuracy of 60.5kPa.N OTE 4—The barometric pressure used in this calculation is the ambient pressure for the laboratory at the time of the test.Many aneroid barometers,such as those used at weather stations and airports,are precorrected to give sea level readings and would not give the correct reading for this test.7.Reagents and Materials7.1Cleaning Solvents—Use suitable solvent capable of cleaning out the specimen from the test cup and drying the test cup and cover.Some commonly used solvents are toluene and acetone.(Warning —Toluene,acetone,and many solvents are flammable and a health hazard.Dispose of solvents and waste material in accordance with local regulations.)8.Sampling8.1Obtain a sample in accordance with instructions given in Practices D4057,D4177,or E300.8.2At least 75mL of sample is required for each test.Referto Practice D4057.When obtaining a sample of residual fuel oil,the sample container shall be from 85to 95%full.For other types of samples,the size of the container shall be chosen such that the container is not more than 85%full or less than 50%full prior to any sample aliquot being taken.For biodiesel (B100)samples,a typical one liter container filled to 85%volume is recommended.8.3Successive test specimens can be taken from the same sample container.Repeat tests have been shown to be within the precisions of the method when the second specimen is taken with the sample container at least 50%filled.The results of flash point determinations can be affected if the sample volume is less than 50%of sample container capacity.8.4Erroneously high flash points may be obtained if pre-cautions are not taken to avoid the loss of volatile material.Do not open containers unnecessarily,to prevent loss of volatile material or possible introduction of moisture,or both.Avoid storage of samples at temperatures in excess of 35°C or 95°F.Samples for storage shall be capped tightly with inner seals.Do not make a transfer unless the sample temperature is at least the equivalent of 18°C or 32°F below the expected flash point.8.5Do not store samples in gas-permeable containers,since volatile material may diffuse through the walls of the enclo-sure.Samples in leaky containers are suspect and not a source of valid results.8.6Samples of very viscous materials shall be heated in their containers,with lid/cap slightly loosened to avoid buildup of dangerous pressure,at the lowest temperature adequate to liquefy any solids,not exceeding 28°C or 50°F below the expected flash point,for 30min.If the sample is then not completely liquefied,extend the heating period for additional 30min periods as necessary.Then gently agitate the sample to provide mixing,such as orbiting the container horizontally,before transferring to the specimen cup.No sample shall be heated and transferred unless its temperatures is more than 18°C or 32°F below its expected flash point.When the sample has been heated above this temperature,allow the sample to cool until its temperature is at least 18°C or 32°F below the expected flash point before transferring.N OTE 5—V olatile vapors can escape during heating when the sample container is not properly sealed.N OTE 6—Some viscous samples may not completely liquefy even after prolonged periods of heating.Care should be exercised when increasing the heating temperature to avoid unnecessary loss of volatile vapors,or heating the sample too close to the flash point.8.7Samples containing dissolved or free water may be dehydrated with calcium chloride or by filtering through a qualitative filter paper or a loose plug of dry absorbent cotton.Warming the sample is permitted,but it shall not be heated for prolonged periods or greater than a temperature of 18°C32°F below its expected flash point.N OTE 7—If the sample is suspected of containing volatile contaminants,the treatment described in 8.6and 8.7should be omitted.9.Preparation of Apparatus9.1Support the manual or automated apparatus on a level steady surface,such as a table.5Supporting data regarding a variant of the cover locking mechanism have been filed at ASTM International Headquarters and may be obtained by requesting Research ReportRR:D02-1706.--`,,``,,`,``,,`,`,,`,,,,`,``,`-`-`,,`,,`,`,,`---9.2Tests are to be performed in a draft-free room or compartment.Tests made in a laboratory hood or in any location where drafts occur are not reliable.N OTE8—A shield,of the approximate dimensions460mm(18in.) square and610mm(24in.)high,or other suitable dimensions,and having an open front is recommended to prevent drafts from disturbing the vapors above the test cup.N OTE9—With some samples whose vapors or products of pyrolysis are objectionable,it is permissible to place the apparatus along with a draft shield in a ventilation hood,the draft of which is adjustable so that vapors can be withdrawn without causing air currents over the test cup during the ignition source application period.9.3Prepare the manual apparatus or the automated appara-tus for operation in accordance with the manufacturer’s in-structions for calibrating,checking,and operating the equip-ment.(Warning—Gas pressure should not be allowed to exceed3kPa(12in.)of water pressure.)9.4Thoroughly clean and dry all parts of the test cup and its accessories before starting the test,to ensure the removal of any solvent which had been used to clean the e suitable solvent capable of removing all of the specimen from the test cup and drying the test cup and cover.Some commonly used solvents are toluene and acetone.(Warning—Toluene, acetone,and many solvents areflammable.Health hazard. Dispose of solvents and waste material in accordance with local regulations.)10.Verification of Apparatus10.1Adjust the automatedflash point detection system (when used)in accordance with the manufacturer’s instruc-tions.10.2Verify that the temperature measuring device is in accordance with6.3.10.3Verify the performance of the manual apparatus or the automated apparatus at least once per year by determining the flash point of a certified reference material(CRM)such as those listed in Annex A4,which is reasonably close to the expected temperature range of the samples to be tested.The material shall be tested according to Procedure A of these test methods and the observedflash point obtained in11.1.8or 11.2.2shall be corrected for barometric pressure(see Section 14).Theflash point obtained shall be within the limits stated in Table A4.1for the identified CRM or within the limits calculated for an unlisted CRM(see Annex A4).10.4Once the performance of the apparatus has been verified,theflash point of secondary working standards (SWSs)can be determined along with their control limits. These secondary materials can then be utilized for more frequent performance checks(see Annex A4).10.5When theflash point obtained is not within the limits stated in10.3or10.4,check the condition and operation of the apparatus to ensure conformity with the details listed in Annex A1,especially with regard to tightness of the lid(A1.1.2.2),the action of the shutter,the position of the ignition source (A1.1.2.3),and the angle and position of the temperature measuring device(A1.1.2.4).After any adjustment,repeat the test in10.3using a fresh test specimen,with special attention to the procedural details prescribed in these test methods.PROCEDURE A11.Procedure11.1Manual Apparatus:11.1.1Ensure that the sample container isfilled to the volume capacity requirement specified in8.2.Fill the test cup with the test specimen to thefilling mark inside of the test cup. The temperature of the test cup and test specimen shall be at least18°C or32°F below the expectedflash point.If too much test specimen has been added to the test cup,remove the excess using a syringe or similar device for withdrawal offluid.Place the test cover on the test cup and place the assembly into the apparatus.Be sure the locating or locking device is properly engaged.If the temperature measuring device is not already in place,insert the device into its holder.11.1.2Light the testflame,and adjust it to a diameter of3.2 to4.8mm(0.126to0.189in.),or switch on the electric igniter and adjust the intensity in accordance with the manufacturer’s instructions.(Warning—Gas pressure should not be allowed to exceed3kPa(12in.)of water pressure.)(Warning—Exercise care when using a gas testflame.If it should be extinguished it will not ignite the vapors in the test cup,and the gas for the testflame that then enters the vapor space can influence the result.)(Warning—The operator should exercise and take appropriate safety precautions during the initial application of the ignition source,since test specimens con-taining low-flash material can give an abnormally strongflash when the ignition source isfirst applied.)(Warning—The operator should exercise and take appropriate safety precau-tions during the performance of these test methods.The temperatures attained during these test methods,up to370°C (698°F),are considered hazardous.)(Warning—As a safety practice,when using automated or manual apparatus,it is strongly advised,before heating the test cup and specimen,to dip the ignitor to check for the presence of unexpected volatile material.)11.1.3Apply the heat at such a rate that the temperature,as indicated by the temperature measuring device,increases5to 6°C(9to11°F)/min.11.1.4Turn the stirring device at90to120rpm,stirring ina downward direction.(Warning—Meticulous attention to all details relating to the ignition source,size of testflame or intensity of the electric ignitor,rate of temperature increase, and rate of dipping the ignition source into the vapor of the test specimen is desirable for good results.)11.1.5Application of Ignition Source:11.1.5.1If the test specimen is expected to have aflash point of110°C or230°F or below,apply the ignition source when the temperature of the test specimen is2365°C or4169°F below the expectedflash point and each time thereafter at a temperature reading that is a multiple of1°C or2°F.Discon-tinue the stirring of the test specimen and apply the ignition source by operating the mechanism on the test cover which controls the shutter so that the ignition source is loweredinto --`,,``,,`,``,,`,`,,`,,,,`,``,`-`-`,,`,,`,`,,`---the vapor space of the test cup in 0.5s,left in its lowered position for 1s,and quickly raised to its upward position.11.1.5.2If the test specimen is expected to have a flash point above 110°C or 230°F,apply the ignition source in the manner described in 11.1.5.1at each temperature increase of 2°C or 5°F,beginning at a temperature of 2365°C or 4169°F below the expected flash point.(Warning—As a safety practice,when using automated or manual apparatus,it is strongly advised that,for an expected flash point above 130°C,to dip the ignitor every 10°C throughout the test until the sample temperature reaches 28°C below the expected flash point and then follow the prescribed dipping procedure.This practice has been shown to reduce the possibility of a fire,and,on average,not to significantly affect the result.A limited study 6has shown that this dipping practice has no observable effect on test method repeatability.)11.1.6When testing materials to determine if volatile ma-terial contamination is present,it is not necessary to adhere to the temperature limits for initial ignition source application as stated in 11.1.5.11.1.7When testing materials where the expected flash point temperature is not known,bring the material to be tested and the tester to a temperature of 1565°C or 60610°F.When the material is known to be very viscous at this temperature,heat the specimen to a starting temperature as described in 8.6.Apply the ignition source,in the manner described in 11.1.5.1,beginning at least 5°C or 10°F higher than the starting temperature.N OTE 10—Flash Point results determined in an “unknown expected flash point mode”should be considered approximate.This value can be used as the expected flash point when a fresh specimen is tested in the standard mode of operation.11.1.8Record as the observed flash point the reading on the temperature measuring device at the time ignition source application causes a distinct flash in the interior of the test cup.The sample is deemed to have flashed when a large flame appears and instantaneously propagates itself over the entire surface of the test specimen.(Warning—For certain mixtures containing halogenated hydrocarbons,such as,methylene chlo-ride or trichloroethylene,no distinct flash,as defined,is observed.Instead a significant enlargement of the test flame (not halo effect)and change in color of the test flame from blue to yellowish-orange occurs.Continued heating and testing of these samples above ambient temperature can result in signifi-cant burning of vapors outside the test cup,and can be a potential fire hazard.See Appendix X1and Appendix X2for more information.)11.1.9When the ignition source is a test flame,the appli-cation of the test flame can cause a blue halo or an enlarged flame prior to the actual flash point.This is not a flash and shall be ignored.11.1.10When a flash point is detected on the first application,the test shall be discontinued,the result discarded,and the test repeated with a fresh test specimen.The first application of the ignition source with the fresh test specimenshall be 2365°C or 4169°F below the temperature at which a flash point was detected on the first application.11.1.11When a flash point is detected at a temperature which is greater than 28°C or 50°F above the temperature of the first application of the ignition source,or when a flash point is detected at a temperature which is less than 18°C or 32°F above the temperature of the first application of the ignition source,the result shall be considered approximate,and the test repeated with a fresh test specimen.Adjust the expected flash point for this next test to the temperature of the approximate result.The first application of the ignition source with the fresh test specimen shall be 2365°C or 4169°F below the temperature at which the approximate result was found.11.1.12When the apparatus has cooled down to a safe handling temperature,less than 55°C (130°F),remove the test cover and the test cup and clean the apparatus as recommended by the manufacturer.N OTE 11—Exercise care when cleaning and positioning the lid assem-bly so not to damage or dislocate the flash detection system or temperature measuring device.See the manufacturer’s instructions for proper care and maintenance.11.2Automated Apparatus:11.2.1The automated apparatus shall be capable of per-forming the procedure as described in 11.1,including control of the heating rate,stirring of the test specimen,application of the ignition source,detection of the flash point,and recording the flash point.11.2.2Start the automated apparatus in accordance with the manufacturer’s instructions.(Warning—Failure to install the sample temperature measuring device correctly,when using automated apparatus,can result in uncontrolled heating of the test portion and potentially a fire.Some automated apparatus include provisions to avoid this occurrence.)The apparatus shall follow the procedural details described in 11.1.3through 11.1.8.PROCEDURE B12.Procedure12.1Manual Apparatus:12.1.1Ensure that the sample container is filled to the volume capacity requirement specified in 8.2.Fill the test cup with the test specimen to the filling mark inside of the test cup.The temperature of the test cup and test specimen shall be at least 18°C or 32°F below the expected flash point.If too much test specimen has been added to the test cup,remove the excess using a syringe or similar device for withdrawal of fluid.Place the test cover on the test cup and place the assembly into the apparatus.Be sure the locating or locking device is properly engaged.If the temperature measuring device is not already in place,insert the device into its holder.12.1.2Light the test flame and adjust it to a diameter of 3.2to 4.8mm (0.126to 0.189in.),or switch on the electric igniter and adjust the intensity in accordance with the manufacturer’s instructions.(Warning—Gas pressure should not be allowed to exceed 3kPa (12in.)of water pressure.)(Warning—Exercise care when using a gas test flame.If it should be extinguished it will not ignite the vapors in the test cup and the gas for the test flame that then enters the vapor space can6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research ReportRR:D02-1652.--`,,``,,`,``,,`,`,,`,,,,`,``,`-`-`,,`,,`,`,,`---。

张海芳，纳日，韩育梅，等. 光谱无损检测技术在农产品产地溯源中的研究进展[J]. 食品工业科技，2023，44（8）：17−25. doi:10.13386/j.issn1002-0306.2022080091ZHANG Haifang, NA Ri, HAN Yumei, et al. Research Progress of Spectral Nondestructive Testing Technology in Traceability of Agricultural Products[J]. Science and Technology of Food Industry, 2023, 44(8): 17−25. (in Chinese with English abstract). doi:10.13386/j.issn1002-0306.2022080091· 未来食品 ·光谱无损检测技术在农产品产地溯源中的研究进展张海芳1，纳　日1，韩育梅2，苏晓燕1（1.内蒙古化工职业学院材料工程系，内蒙古呼和浩特 010070；2.内蒙古农业大学食品科学与工程学院，内蒙古呼和浩特 010018）摘　要：实现农产品产地溯源的无损检测，是建立农产品质量安全追溯体系的重要途径，也是保障食品安全质量、维护消费者合法权益的有效手段。

相比于传统的检测方法，无损检测技术因其能实现不破坏被检样品的同时获取内外部有效信息的优点而被广泛应用于食品的产地溯源领域。

本文主要概述了近红外光谱、高光谱成像、拉曼光谱三种光谱检测技术的原理及其在不同种类可食用农产品产地溯源中的最新应用现状，得出各光谱检测技术在农产品产地鉴别方面具有一定的可行性，同时对未来的研究方向作了展望，以期为农产品产地溯源的无损检测技术体系研究提供理论参考。

关键词：产地溯源，农产品，近红外光谱，高光谱成像，无损检测本文网刊:中图分类号：TS207.3 文献标识码：A 文章编号：1002−0306（2023）08−0017−09DOI: 10.13386/j.issn1002-0306.2022080091Research Progress of Spectral Nondestructive Testing Technology inTraceability of Agricultural ProductsZHANG Haifang 1，NA Ri 1，HAN Yumei 2，SU Xiaoyan 1（1.Department of Materials Engineering, Inner Mongolia Chemical Vocational College, Hohhot 010070, China ；2.Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot 010018, China ）Abstract ：Realizing nondestructive testing for traceability of the origin of agricultural products is an important way to establish a traceability system for the quality and safety of agricultural products, and an effective means to guarantee the quality of food safety and safeguard the legitimate rights and interests of consumers. Compared with traditional testing methods, nondestructive testing technology is widely used in the field of food traceability because it can achieve the advantages of obtaining internal and external effective information without damaging the inspected samples. This paper provides an overview of NIR spectroscopy, NIR testing, and NIR testing. In this paper, the principles of three spectral detection techniques, namely, near-infrared spectroscopy, hyperspectral imaging and Raman spectroscopy, and their latest applications in the origin traceability of different types of edible agricultural products are outlined, and the feasibility of each spectral detection technique in the origin identification of agricultural products is concluded. At the same time, the future research directions are prospected in order to provide theoretical references for the research of nondestructive testing technology system for origin traceability of agricultural products.Key words ：origin traceability ；agricultural products ；near infrared spectroscopy ；hyperspectral imaging ；nondestructive testing收稿日期：2022−08−10基金项目：内蒙古自治区高等学校科学研究项目（NJZY17449）。

coco数据集评估指标 mapThe COCO (Common Objects in Context) dataset is a widely used benchmark for object detection, segmentation, and captioning tasks in computer vision. When it comes to evaluating the performance of models trained on this dataset, the mean average precision (mAP) is a key metric that is often used. mAP is a measure of the accuracy of an object detection model, taking into account both the precision and recall of the model's predictions. It provides a single, easy-to-understand value that summarizes the overall performance of the model across all classes and all levels of confidence.One of the main advantages of using mAP as an evaluation metric for the COCO dataset is its ability to capture the trade-off between precision and recall. This is important because in object detection tasks, it is crucial to not only correctly identify the presence of an object but also to accurately localize it within the image. By considering both precision and recall, mAP provides acomprehensive assessment of the model's performance in this regard.From a practical standpoint, mAP is also useful for comparing the performance of different models or algorithms on the COCO dataset. Since mAP provides a single numerical value that summarizes the overall performance, it allowsfor easy and direct comparisons between different approaches. This is particularly valuable in research and development, where the goal is often to identify the most effective techniques for object detection and segmentation.However, it is important to note that mAP is not without its limitations. One potential drawback is that it does not provide detailed insights into the specific strengths and weaknesses of a model. For example, a model with high mAP may still perform poorly on certain classes or under specific conditions. In such cases, additional analysis beyond mAP may be necessary to fully understand the model's performance.Furthermore, the calculation of mAP can be sensitive tocertain parameters, such as the threshold for defining a true positive detection. This means that small changes in these parameters can lead to significant differences in the reported mAP, making it important to carefully consider the specific settings used when interpreting and comparing mAP values.In conclusion, while mAP is a valuable and widely used evaluation metric for the COCO dataset, it is important to consider its limitations and to supplement its use with additional analyses when necessary. By doing so, researchers and practitioners can gain a more comprehensive understanding of the performance of object detection and segmentation models on this important benchmark.。