Quenched Hadron Spectroscopy with Improved Actions
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引用格式:李傲, 肖文波, 张濬哲, 等. 太阳能电池阻抗谱测量方法及其应用进展[J]. 中国测试,2024, 50(1): 1-8. LI Ao, XIAO Wenbo, ZHANG Junzhe, et al. Research progress of solar cell impedance spectroscopy measurement method and its application[J].China Measurement & Test, 2024, 50(1): 1-8. DOI: 10.11857/j.issn.1674-5124.2022080063太阳能电池阻抗谱测量方法及其应用进展李 傲1, 肖文波1, 张濬哲2, 吴华明1, 王树鹏3(1. 南昌航空大学 无损检测技术教育部重点实验室,江西 南昌 330063; 2. 南昌航空大学材料科学与工程学院,江西 南昌330063; 3. 中国航发沈阳黎明航空发动机有限责任公司,辽宁 沈阳 110043)摘 要: 阻抗谱测量技术是研究太阳能电池的重要手段。
该文首先对近几年提出的阻抗谱测量方法进行评述,分析各类方法的优缺点。
通过对阻抗谱测量方法的研究,发现不同测量方法之间的差异主要体现在其效率、精度以及成本等方面。
其次,分析阻抗谱在太阳电池故障检测、电子输运、界面研究等方面的应用情况,指出它们评价电池动态行为时存在的不足之处。
最后,总结阻抗谱测量方法未来发展方向及应用需求。
关键词: 太阳能电池; 阻抗谱; 故障评估; 电子输运; 界面研究中图分类号: TM930.12;TB9文献标志码: A文章编号: 1674–5124(2024)01–0001–08Research progress of solar cell impedance spectroscopy measurementmethod and its applicationLI Ao 1, XIAO Wenbo 1, ZHANG Junzhe 2, WU Huaming 1, WANG Shupeng 3(1. Key Laboratory of Nondestructive Testing, Ministry of Education, Nanchang Hangkong University, Nanchang 330063, China; 2. Material Science and Engineering Institute, Nanchang Hangkong University, Nanchang 330063,China; 3. AECC Shenyang Liming Aero-Engine Co., Ltd., Shenyang 110043, China)Abstract : Impedance spectroscopy is an important means of studying solar cells. Firstly, this paper reviews the impedance spectroscopy measurement methods proposed in recent years, and analyzes the advantages and disadvantages of each method. Through the study of impedance spectroscopy measurement methods, it is found that the differences between different measurement methods are mainly reflected in their efficiency,accuracy and cost. Secondly, the application of impedance spectroscopy in fault detection, electron transport,and interface research are analyzed, and their shortcomings in evaluating the dynamic behavior of cells are pointed out. Finally, the future development direction and application requirements of impedance spectroscopy measurement methods are summarized and analyzed.Keywords : solar cells; impedance spectrum; failure assessment; electron transport; interface research收稿日期: 2022-08-11;收到修改稿日期: 2022-10-05基金项目: 国家自然科学基金(12064027,62065014);研究生创新专项资金(YC2022-118,YC2022-113)作者简介: 李 傲(1999-),男,河北保定市人,硕士研究生,专业方向为光伏检测技术。
EPR Spectroscopy in Chemical Analysis引言EPR(electron paramagnetic resonance)谱学是一种常用于化学分析的技术。
它是基于自由电子在磁场中的共振吸收现象。
在分析中,EPR谱学主要用于检测和鉴定化合物中的自由基和过渡金属离子。
本文将介绍EPR谱学在化学分析中的重要性、原理、应用和未来发展方向。
EPR谱学的重要性自由基和过渡金属离子在化学中起着至关重要的作用。
它们参与了许多重要的化学反应,如氧化、还原、分子裂解和配位化学。
此外,它们还与环境污染、电化学和生化过程等方面有关。
因此,EPR谱学在化学研究中具有重要的意义。
EPR谱学的原理EPR谱学的核心原理是电子在外磁场中的共振吸收。
在一个外磁场中,自由电子具有两个自旋态,即向上和向下的自旋态。
如果电子处于向上的自旋态,那么它会向下跳跃,反之亦然。
这种跳跃的能量与外磁场的频率相匹配。
因此,如果在一个恰当的外磁场下,电磁波的频率与电子的共振频率相同,那么电磁波就会被吸收。
这个吸收的信号可以通过一个探测器来检测。
EPR谱学的应用EPR谱学可以被广泛地应用于化学分析中。
它可以用来检测许多物质,如自由基和过渡金属离子。
这就包括了许多有机和无机化合物,例如有机自由基、自由基反应中的过渡态、金属离子和有机磁砂等。
在许多情况下,EPR谱学可以被用来确定一个化合物的结构。
因为自由基和过渡金属离子的性质可以很好地反映其所在化合物的结构。
此外,EPR谱学也可以用于生化分析,例如查找具有生物活性的自由基化合物。
未来的发展趋势随着科学技术的迅速发展,EPR谱学也不断地发展。
未来,人们将研究如何利用EPR谱学来解决更多的化学问题。
例如,使用EPR谱学来研究化学催化过程或电子传输过程的机理。
此外,还有一些新的技术正在开发,例如将EPR谱学与磁共振成像技术相结合,从而产生更详细精确的图像。
总之,EPR谱学将会在化学分析中发挥越来越重要的作用。
基于小波空间特征匹配及表面增强拉曼光谱技术快速检测混合物中的甲氨蝶呤和伏立康唑刘察;臧颖超;曾惠桃;范夏琼;张志敏;卢红梅【摘要】为实现混合物中目标化合物的快速检测,合成了对甲氨蝶呤和伏立康唑具有普适性响应的金纳米复合(AuNPS-PDDA)基底,借助表面增强拉曼光谱技术,结合化学计量学方法,通过连续小波变换将甲氨蝶呤和伏立康唑的光谱信号转换到小波空间,依据小波空间特征匹配分析混合物的拉曼光谱,显著减轻信号中基线变化和随机噪声的影响,成功地识别出混合物中1.0×10-8mol/L甲氨蝶呤和2.86×10-4 mol/L伏立康唑.其中,甲氨蝶呤和伏立康唑的小波特征匹配系数均大于0.96,高于传统的命中质量系数,且采用非负最小二乘法成功实现了两种物质含量比例的确定,实验的组分比例预测值与真实值之间相关性大于0.98.实验结果表明,小波空间特征匹配结合表面增强拉曼光谱技术能有效地识别且半定量混合物中的目标化合物.【期刊名称】《分析测试学报》【年(卷),期】2019(038)006【总页数】7页(P668-674)【关键词】表面增强拉曼光谱技术;特征匹配;甲氨蝶呤;伏立康唑【作者】刘察;臧颖超;曾惠桃;范夏琼;张志敏;卢红梅【作者单位】中南大学化学化学工学院,湖南长沙410083;中南大学化学化学工学院,湖南长沙410083;中南大学化学化学工学院,湖南长沙410083;中南大学化学化学工学院,湖南长沙410083;中南大学化学化学工学院,湖南长沙410083;中南大学化学化学工学院,湖南长沙410083【正文语种】中文【中图分类】O657.3;TQ460.72拉曼光谱技术是一种重要的分析检测技术,广泛应用于各种领域,如古文物鉴定、生物蛋白质研究、医药物质检测、食物安全现场检测等[1]。
该技术无需复杂的样本预处理,几乎可以用于任何环境[2]。
拉曼光谱还包含了丰富的物质结构信息,被称为分子的“指纹图谱”[3]。
Electrochemical Impedance Spectroscopy : A Powerful Tool for Analyzing Electrochemical Systems(EIS) is a powerful analytical technique for investigating electrochemical systems. Unlike other traditional techniques, which only provide information about the overall response of the system, EIS provides detailed information about the electrical impedance of the system as a function of frequency. This makes it possible to study the mechanisms of electron transfer, adsorption, diffusion, and other electrochemical processes at the interface between the electrode and the electrolyte.The principle of EIS is based on the application of a small sinusoidal perturbation to the potential or current of an electrochemical system and the measurement of the resulting response. The impedance of the system can be represented by a complex quantity, Z, which is the ratio between the amplitude of the applied perturbation and the resulting response. The impedance is usually expressed in terms of its real and imaginary components, Z' and Z", respectively, which correspond to the resistance and capacitance of the system. By measuring the impedance as a function of frequency, it is possible to obtain a spectrum that provides valuable information about the electrochemical properties of the system.EIS can be used for a wide range of applications, including corrosion studies, catalysis, electroanalysis, and bioelectrochemistry. In corrosion studies, for example, EIS can be used to determine the corrosion rate, corrosion mechanism, and corrosion resistance of metallic materials in different environments. In catalysis, EIS can be used to study the interaction between the catalyst and the reactants, the adsorption of intermediates, and the mechanism of the reaction. In electroanalysis, EIS can be used to detect and quantify trace amounts of analytes, such as heavy metals, sugars, and proteins, in complex matrices. In bioelectrochemistry, EIS can be used to study the interaction between biomolecules and electrodes, the redox properties of enzymes, and the mechanism of electron transfer in biological systems.To perform EIS measurements, a special instrument called an impedance analyzer is required. The impedance analyzer applies a small AC signal to the system and measures both the magnitude and the phase of the resultant response. The frequency of the applied signal is typically swept over a range of several orders of magnitude to obtain a full spectrum of the impedance. The spectrum can be analyzed using different mathematical models, such as equivalent circuits, which provide a quantitative description of the underlying electrochemical processes.One of the advantages of EIS is its non-destructive nature, which allows for the repeated measurement of the same system over time. This makes it possible to monitor the evolution of the electrochemical properties of the system under different conditions, such as temperature, pH, and pressure. EIS can also be used in situ or in operando, which means that the measurements can be performed while the system is in use. This makes it possible to study the electrochemical properties of complex and dynamic systems, such as fuel cells, batteries, and sensors.In conclusion, is a powerful and versatile tool for analyzing electrochemical systems. Its ability to provide detailed information about the electrochemical properties of the system as a function of frequency makes it a valuable technique for studying the mechanisms of electron transfer, adsorption, and diffusion. EIS has broad applications in corrosion studies, catalysis, electroanalysis, and bioelectrochemistry, and its non-destructive and in situ nature make it a valuable tool for monitoring the evolution of electrochemical systems over time.。
壳层隔绝纳米粒子增强拉曼光谱检测乳腺浸润性导管癌组织的生物学特点及其临床意义张海鹏;吴迪;张湜;付彤;路璐;范志民;郑超;韩冰【期刊名称】《吉林大学学报(医学版)》【年(卷),期】2014(000)005【摘要】目的:采用壳层隔绝纳米粒子增强拉曼光谱(SHINERS)技术检测乳腺浸润性导管癌(IDC)组织和正常乳腺组织,探讨乳腺 IDC的光谱学特点、生物学特征和鉴别方法。
方法:收集行乳腺外科手术患者的乳腺组织冰冻切片,共24例,均为女性,年龄27~59岁;其中乳腺 IDC组织15例,正常乳腺组织9例。
冰冻切片解冻后先行普通拉曼光谱检测,加壳层隔绝纳米粒子(SHINs)后再次检测。
共收集了263个拉曼光谱和249个SHINERS光谱,所有光谱均进行基线修正拟合,再将所有的光谱用 Adjacent-Averaging 算法进行15点平滑。
结果:正常乳腺组织特征峰出现在1090、1157、1262、1300、1442、1658、1745和1874 cm-1;在加入SHINs后,少数特征峰的峰位出现2~3 cm-1位移,其中1090和1157 cm-1相对强度明显增加,出现1496 cm-1特征峰。
乳腺 IDC组织普通拉曼光谱检测可见多个核酸特征峰(包括878、1086和1157 cm-1);加入SHINs后,明显看到1004、1157、1526和1658 cm-1相对强度增加,脂类的特征峰1745和1442 cm-1为C=O和CH2伸缩振动, IDC 组织相对于正常组织表现出2~3 cm-1的蓝移;类胡萝卜素的特征峰出现在1527 cm-1;核酸的特征峰1090 cm-1蓝移至1086 cm-1。
结论:拉曼光谱能够发现乳腺 IDC组织DNA、蛋白质及类胡萝卜素与正常乳腺组织的差异。
SHINERS对不同类型的乳腺组织最大增强的特征峰不同,可以用来区分乳腺 IDC组织和正常乳腺组织。
%Objective To identify normal breast tissue and breast invasive ductal carcinoma (IDC)tissue by shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), and to explore the biological characteristics of IDC and the identification method by discussing its spectroscopy characteristics.Methods The frozen section of breast tissue from 24 patients (female,aged 27-59 years)underwent routine surgical resection were obtained. 9 cases of normal breast tissue and 1 5 cases of IDC breast tissue were detected by Raman spectroscopy and then SHINERS technique was utilized.A total of 263 Raman spectra and 249 SHINERS spectra were obtained.All the spectra were dealt with baseline corrected by fitting and subtracting a third-order polynomial and then smoothed with a 15-point Adjacent-Averaging.Results The characteristic peak of normal breast tissue appeared at 1 090,1 157, 1 262,1 300,1 442,1 658,1 745,and 1 874 cm-1 .After adding shell-isolated nanoparticles (SHINs),some peaks shifted at 2-3 cm-1 ,and the relative strengthes of 1 090 and 1 157 cm-1 were significantly increased,and the characteristic peak at 1 496 cm-1 appeared.The Raman spectroscopy showed there were more nucleic acid characteristic peaks (including 878,1 086,1 157 cm-1 )in the breast IDC tissue;after adding SHINs,the relative strengthes of 1 004,1 157,1 526,and 1 658 cm-1 were increased,the characteristic peak of lipid at 1 745 cm-1 and 1 442 cm-1 stemmed from the C=O and CH2 stretchingpared with the normal breast tissue, the breat IDC tissue showed a blue shift of 2-3 cm-1 . The characteristic peaks of nucleic acid had the blue shift from 1 086 cm-1 to 1 090 cm-1 , and the characteristicpeak of β-carotene emerged at 1 527 cm-1 . Conclusion Raman spectra can discover the differences of the characteristic peaks of DNA,β-carotene,and protein between breast IDC and normal breasttissues;SHINERS can distinguish breast IDC tissue from normal breast tissue successfully.【总页数】5页(P1064-1068)【作者】张海鹏;吴迪;张湜;付彤;路璐;范志民;郑超;韩冰【作者单位】吉林大学第一医院产科,吉林长春 130021;吉林大学第一医院乳腺外科,吉林长春 130021;;吉林大学第一医院乳腺外科,吉林长春 130021;吉林大学第一医院乳腺外科,吉林长春 130021;吉林大学第一医院乳腺外科,吉林长春130021;吉林大学第一医院乳腺外科,吉林长春 130021;吉林大学第一医院乳腺外科,吉林长春 130021【正文语种】中文【中图分类】R737.9【相关文献】1.基于壳层隔绝纳米粒子和在线裂解-吹扫捕集的血液氰化物表面增强拉曼光谱快速检测方法 [J], 朱颖洁;郭磊;刘易;龚莹;邱泽武;吴剑峰;谢剑炜2.基于有孔壳层隔绝纳米粒子增强拉曼光谱的芥子气现场检测新方法 [J], 高敬;吴剑峰;高海月;郭磊;谢剑炜3.壳层隔绝纳米粒子增强拉曼光谱技术对丝织品上茜草染料的快速分析研究 [J], 成小林;杨琴;赵丹丹;雷勇4.新型检测技术-壳层隔绝纳米粒子增强拉曼光谱 [J],5.壳层隔绝纳米粒子增强拉曼光谱新技术 [J], 张建琛因版权原因,仅展示原文概要,查看原文内容请购买。
拉曼光谱检测动脉粥样硬化斑块的意义
徐宝华;赵慧颖
【期刊名称】《国际心血管病杂志》
【年(卷),期】2005(032)004
【摘要】动脉粥样硬化不稳定斑块的破裂是引发急性冠脉综合征的主要原因,因此及早发现并对其进行干预具有重要意义.拉曼光谱与血管内超声等方法不同,可对动脉粥样硬化斑块的组成成分进行定位及定量的检测,识别性较高,且对组织无破坏性,对发现不稳定斑块有独特的优越性.
【总页数】3页(P232-234)
【作者】徐宝华;赵慧颖
【作者单位】130021,吉林大学第一临床医院心血管科;130021,吉林大学第一临床医院心血管科
【正文语种】中文
【中图分类】R445
【相关文献】
1.壳层隔绝纳米粒子增强拉曼光谱检测乳腺浸润性导管癌组织的生物学特点及其临床意义 [J], 张海鹏;吴迪;张湜;付彤;路璐;范志民;郑超;韩冰
2.早期稳定型动脉粥样硬化斑块模型兔损伤区拉曼光谱特征及旋转手法的影响 [J], 谌祖江;黄学成;向孝兵;陈超;李义凯;
3.早期稳定型动脉粥样硬化斑块模型兔损伤区拉曼光谱特征及旋转手法的影响 [J], 谌祖江;黄学成;向孝兵;陈超;李义凯
4.动脉粥样硬化斑块的微区拉曼光谱检测 [J], 赵慧颖;徐宝华;马小欣
5.稳定冠状动脉粥样硬化斑块的临床意义——麝香保心丸稳定冠状动脉粥样硬化斑块的研究进展 [J], 顾宁
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生态毒理学报Asian Journal of Ecotoxicology第18卷第6期2023年12月V ol.18,No.6Dec.2023㊀㊀基金项目:青年北京学者(陈瑞);国家自然科学基金资助项目(82241084)㊀㊀第一作者:王惠桐(2000 ),女,医学学士,研究方向为生态毒理学,E -mail:**************** ㊀㊀*通信作者(Corresponding author ),E -mail:*****************.cnDOI:10.7524/AJE.1673-5897.20230730001王惠桐,李卿,陈汉清,等.基于表面增强拉曼光谱的微纳塑料肝脏内暴露检测方法研究[J].生态毒理学报,2023,18(6):187-195Wang H T,Li Q,Chen H Q,et al.Surface -enhanced Raman spectroscopy -based detection methods of intrahepatic exposure of micro(nano)-plastics [J].Asian Journal of Ecotoxicology,2023,18(6):187-195(in Chinese)基于表面增强拉曼光谱的微纳塑料肝脏内暴露检测方法研究王惠桐,李卿,陈汉清,陈瑞,李晓波首都医科大学公共卫生学院,北京100069收稿日期:2023-07-30㊀㊀录用日期:2023-10-06摘要:微纳塑料因其难以降解和小尺寸特性可能危害人类健康,目前已报道大量微纳塑料检测手段,但是主要集中于食物和环境样本中,尚缺乏评估微纳塑料生物体内暴露水平的研究㊂表面增强拉曼光谱(SERS)因其灵敏度高㊁检测速度快和数据处理简单等优点,具有良好的应用前景㊂本研究基于金核银壳为基底的SERS 技术,旨在开发一种高灵敏准确的检测手段评估微纳塑料肝脏内的暴露水平㊂首先对尺寸为1000nm 的聚苯乙烯微塑料进行物理化学性质表征㊂随后通过柠檬酸钠还原法成功制备形貌完整且粒径分布均一的30nm 金核银壳纳米粒子(Au @Ag NPs)㊂采用SERS 对梯度稀释的微塑料标准品溶液进行检测,SERS 成功检测浓度范围在10~0.05mg ㊃mL -1的聚苯乙烯微塑料标准品,绘制标准曲线并计算最低检测限为0.0175mg ㊃mL -1㊂构建小鼠微塑料尾静脉注射模型,使用SERS 对小鼠肝脏内微塑料浓度进行检测,计算得到肝组织悬液中的微塑料浓度为0.493mg ㊃mL -1㊂本研究建立的以Au @Ag 为基底的SERS 方法可实现肝脏内微塑料浓度的精确定量,弥补微塑料器官内暴露水平评价方法的空缺,为微塑料对人体危害的内暴露研究提供技术支持㊂关键词:微塑料;表面增强拉曼光谱;肝脏内暴露;检测技术文章编号:1673-5897(2023)6-187-09㊀㊀中图分类号:X171.5㊀㊀文献标识码:ASurface-Enhanced Raman Spectroscopy-Based Detection Methods of Intra-hepatic Exposure of Micro (nano )-PlasticsWang Huitong,Li Qing,Chen Hanqing,Chen Rui,Li XiaoboCollege of Public Health,Capital Medical University,Beijing 100069,ChinaReceived 30July 2023㊀㊀accepted 6October 2023Abstract :Micro(nano)-plastics has become a potential threat to human health due to their degradation resistance and small particle size.Numerous detection methods for micro (nano)-plastics have been developed,which are mainly applied in food or environmental samples.Surface -enhanced Raman spectroscopy (SERS)has the advantages of high sensitivity,fast detection speed,and simple data processing,which can be potentially used in micro(nano)-plastics detection.Our study aims to establish a highly sensitive and accurate detection method,based on SERS,to evaluate the internal exposure level of micro(nano)-plastic.The physical and chemical properties of 1000nm poly -styrene microplastics were characterized.Subsequently,gold core silver shell nanoparticles (Au @Ag NPs)with complete morphology and 30nm particle size were prepared by sodium citrate reduction method.Results showed188㊀生态毒理学报第18卷that SERS could successfully detect polystyrene microplastics standard solution with a concentration ranging from 10mg㊃mL-1to0.05mg㊃mL-1and the limit of detection was0.0175mg㊃mL-1.Finally,the microplastics exposure model in mice was constructed by tail vein injection,and the concentration of microplastics in liver tissue suspen-sion was0.493mg㊃mL-1by SERS detection.In brief,the SERS method based on Au@Ag accurately quantify the concentration of microplastics in liver and provide technics for the study of micro(nano)-plastics damage to hu-man body.Keywords:microplastics;surface-enhanced Raman spectroscopy;intrahepatic exposure level;detection technology㊀㊀随着塑料制品的大量使用,微纳塑料污染问题逐渐成为人们重视的焦点㊂微纳塑料是一类直径小于5mm的塑料颗粒,一般根据其来源,可分为初生微塑料和次生微塑料㊂初生微塑料是指生产的直径小于5mm并直接释放到环境中的塑料㊂次生微塑料是通过物理㊁化学和生物等多种方式,使大体积的塑料降解㊁破碎形成的微塑料颗粒[1]㊂这些微塑料可以通过风㊁河流㊁地下径流和渗透等运输途径在土壤㊁大气和水环境中迁移,目前已经在室内空气㊁南极㊁北冰洋和马里亚纳海沟等地方都检测到了微塑料的存在[2]㊂环境中的微纳塑料能够通过消化道摄入㊁呼吸道吸入和皮肤直接接触等多种途径进入人体,并对人体造成潜在的健康威胁[3]㊂目前已在母乳[4]㊁肺部组织[5]和精液[6]等生物介质中检测到微纳塑料的存在㊂进入人体后,微纳塑料高表面积的特点可能会导致氧化应激和细胞毒性[7],而微纳塑料难以降解的特点又限制了它的排出,最终导致慢性炎症的发生[8]㊂此外,微纳塑料还可能导致免疫和神经退行性疾病发病率的增加[9]㊂目前研究报道的微纳塑料检测主要手段包括热分析法和光谱分析法[10]㊂其中热分析法是破坏性方法,通过破坏微纳塑料检测样品,且不能提供有关微纳塑料数量和大小的相关信息[11]㊂光谱分析法主要包括傅里叶变换红外光谱法和拉曼光谱法,其中傅里叶变换红外光谱法不能识别尺寸小于20μm的微纳塑料颗粒㊂而拉曼光谱法是根据光的非弹性散射形成的光谱,可以通过分析散射光谱,获得分子运动的信息,从而获得材料的结构信息㊂但是该方法容易受到荧光干扰的影响,影响微纳塑料的识别,且灵敏度不高,难以实现痕量水平的化学和生物分析[12]㊂本课题将使用表面增强拉曼光谱法,它是在拉曼光谱技术上发展起来的一种新型分析手段,这种技术主要利用粗糙贵金属表面来吸附被测物质,使待测物质拉曼信号急剧增强,从而提高痕量污染物甚至是单分子的灵敏度[13]㊂表面增强拉曼光谱因为其灵敏度高㊁检测速度快㊁样品需求量少㊁无损㊁抑制荧光背景㊁数据处理简单和独特的指纹图谱特性等优点,很好地弥补了传统的微塑料检测方法的缺点,在检测微纳塑料方面展现出良好的应用前景㊂金(Au)和银(Ag)作为粗糙贵金属都具有良好的增强拉曼活性㊂因为电磁波可以激发Au㊁Ag的表面等离子体共振(surface plasmon resonance,SPR),使得Au和Ag表面的电场强度显著增强,因此靠近金属的分子受到电场增强的影响,拉曼信号也急剧增强㊂其中Ag基纳米材料的增强能力最强[14]㊂目前有研究表明,Ag与Au所合成的纳米异质结构由于有电子补偿现象,因此表面均匀,且稳定性较好,更适用于微纳塑料检测方面的表面增强拉曼光谱应用[15]㊂因此本实验采用Au@Ag NPs作为SERS基底㊂Xu等[16]考虑到微纳塑料的疏水问题,将金纳米颗粒(Au NPs)掺杂滤纸作为柔性SERS基底,可有效在纤维孔隙中捕获微纳塑料,并成功在自来水和池塘水中检测到了微纳塑料,证明了SERS检测微塑料的可行性㊂Jeon等[17]用再生纤维素(RC)和金纳米棒(Au NRs)和银纳米线(Ag NWs)通过简单的真空辅助过滤方法构建SERS基底,进行快速微纳塑料检测㊂Ag NWs网络结构致密,活性更好,同时Ag NWs/RC薄膜可以检测低至0.1mg㊃mL-1的微塑料㊂Lê等[18]将银金纳米星插入阳极氧化铝纳米孔中,以此作为表面增强拉曼光谱衬底,成功从水中检测到0.4μm的微纳塑料颗粒㊂SERS弥补了传统的微纳塑料检测方法繁琐,样品预处理程序繁杂,灵敏度低等缺点,在检测微纳塑料方面具有巨大的发展空间㊂值得注意的是,目前大部分研究都聚焦于环境样品中的微纳塑料的检测,忽略了微纳塑料进入体内后器官暴露水平的检测,缺少人体摄入情况的相关研究,而肝脏血供丰富又是人体最大的解毒器官,微纳塑料会大量富集在肝脏内㊂所以本实验将使用SERS检测肝组织内微纳塑料的暴露情况,对微塑第6期王惠桐等:基于表面增强拉曼光谱的微纳塑料肝脏内暴露检测方法研究189㊀料颗粒污染的人类健康风险评估提供数据,为推出相应的公共卫生政策提供理论依据,为确定微纳塑料对人体的危害和公共卫生风险提供坚实的基础㊂1㊀材料与方法(Materials and methods)1.1㊀试剂主要试剂信息见表1,所有试剂均为分析纯㊂1.2㊀仪器主要仪器信息见表2㊂1.3㊀SERS检测条件本实验中的拉曼光谱数据采集均使用实验室配置的拉曼光谱仪进行检测㊂该拉曼光谱仪的最大激光功率为275mW,激光波长为785nm,光斑直径约为105μm㊂实验中一般将最大激发功率的30%设置为实验激发功率,积分时间设置为10s㊂在检测过程中,每个样品随机选择5个区域进行拉曼信号采集,并计算5次测量结果的平均值和标准差作为拉曼光谱数据㊂1.4㊀实验动物所有与本课题有关的动物实验均已获得首都医科大学实验动物福利与伦理委员会的批准㊂本实验采用清洁级C57BL/6雄性小鼠,6~8周龄,体质量24~30g,环境温度为21~25ħ,湿度为50%左右㊂在整个研究进程中,小鼠可自由进食标准小鼠生长饲料㊂小鼠自由饮食饮水,适应环境一周后再进行随机分组和实验㊂1.5㊀Au NPs的制备本实验采用改进的Frens法进行Au NPs的制备㊂采用柠檬酸钠为还原剂,还原氯金酸溶液制备粒径大小约为30nm的Au NPs㊂具体操作步骤如下㊂(1)1%氯金酸溶液制备:称量2g四水合氯金酸粉末,溶于200mL去离子水,放入棕色细口试剂瓶中,避光保存备用㊂(2)1%柠檬酸钠溶液制备:称量1g柠檬酸三钠固体粉末,溶于100mL去离子水中,放入棕色细口试剂瓶中,避光保存备用㊂(3)取200mL的锥形瓶,先用去离子水清洗3遍,再加入干净的磁力搅拌子,用去离子水清洗2遍㊂(4)量取150mL去离子水,加入锥形瓶中,先向锥形瓶中加入1.5mL1%的氯金酸溶液,混合均匀,再放到搅拌器上加热㊂(5)溶液沸腾后,开启搅拌,转速为600r㊃min-1,一次性加入2.25mL1%的柠檬酸钠溶液,持续搅拌15min㊂(6)反应结束后,溶液呈红色㊂停止加热,持续搅拌至室温,即可得到粒径约为25nm的Au NPs㊂表1㊀主要实验试剂Table1㊀Main experimental reagents试剂Reagent 纯度Purity生产厂家Manufacturer单分散聚苯乙烯微球Monodisperse polystyrene microspheres-天津倍思乐Beisile,Tianjin 四水合氯金酸Chloroauric acid hydratedȡ99.8%国药集团Sinopharm 柠檬酸钠Sodium citrateȡ99%国药集团Sinopharm硝酸银Silver nitrateȡ99.8%国药集团Sinopharm 单晶硅片Monocrystalline silicon wafer-浙江立晶Lijing,Zhejiang 磷酸盐缓冲液Phosphate buffer-北京索莱宝Solarbio,Beijing表2㊀主要实验仪器Table2㊀Main experimental instruments仪器名称Instrument 型号Model生产厂家Manufacturer加热电磁搅拌器Heating electromagnetic stirrer BS230中国北京世纪华科SJHK,Beijing,China 拉曼光谱仪Raman spectrometer BWS465B&W Tek,USA透射电子显微镜(TEM)Transmission electron microscope(TEM)JEM-2100日本电子株式会社JEOL,Japan扫描电子显微镜(SEM)Scanning electron microscope(SEM)S-4800日本日立Hitachi,Japan 紫外-可见光吸收光谱仪UV-vis absorption spectrometer UV-2700i日本岛津Shimadzu,Japan Zeta电位及粒径分析仪Zeta potential and size analyzer NanoBrook-Omni Brookhaven,USA 浓缩仪Concentrator Concentrator plus德国艾本德Eppendorf,German190㊀生态毒理学报第18卷1.6㊀Au@Ag NPs的制备采用柠檬酸钠还原法,还原硝酸银,在胶体金纳米粒子表面上包裹银层,得到粒径大小约为30nm 的Au@Ag NPs㊂具体操作步骤如下㊂(1)硝酸银溶液的制备:称取2.25mg硝酸银固体粉末溶于1mL 去离子水中,获得硝酸银溶液㊂(2)取200mL的锥形瓶,先用去离子水清洗3遍,再加入干净的磁力搅拌子,再用去离子水清洗2遍㊂(3)取75mL上述制备的25nm Au NPs于锥形瓶中,液体定容至150mL㊂(4)向锥形瓶中加入1.5mL1%柠檬酸钠溶液后,将其放到搅拌器上,加热至沸腾后再开启搅拌㊂(5)向步骤4溶液中快速滴加1mL硝酸银溶液,加热搅拌20min,充分反应后,关闭加热,继续搅拌至室温,即可完成银层生长,得到粒径大小约为30nm的Au @Ag NPs㊂(6)取出7500r㊃min-1条件下离心6min,弃去上清,使用30μL去离子水重悬备用㊂1.7㊀Au@Ag NPs的物理化学性质表征将制备完成的Au NPs㊁Au@Ag NPs使用去离子水稀释10倍,混匀后超声处理10s,使用Zeta电位及粒径分析仪表征Au@Ag NPs粒径及Zeta电位变化,使用紫外-可见光吸收光谱仪记录Au NPs㊁Au@Ag NPs的主要吸收峰㊂将Au@Ag NPs使用无水乙醇溶液稀释200倍,混匀后超声处理,取1μL溶液滴加于碳支持膜上,晾干后用于透射电子显微镜观察Au@Ag NPs形态㊂1.8㊀拉曼光谱对微塑料的检测应用配制不同浓度聚苯乙烯微塑料标准品溶液,将微塑料标准品浓度稀释为10~0.1mg㊃mL-1,分别滴加在硅片上,干燥后使用拉曼光谱仪检测并收集微塑料标准品的拉曼光谱信号㊂1.9㊀金核银壳SERS基底对微塑料的检测应用配制不同浓度聚苯乙烯微塑料标准品溶液,将浓度稀释为5~0.05mg㊃mL-1㊂将95μL不同浓度的微塑料标准品溶液分别与5μL Au@Ag NPs溶液充分震荡混匀㊂然后分别滴加在硅片上,干燥后使用拉曼光谱仪检测并收集微塑料标准品的SERS 信号㊂1.10㊀建立小鼠微塑料急性暴露模型将雄性C57BL/6小鼠随机分为2组,分别为对照组和微塑料染毒组,每组3只㊂对照组尾静脉注射PBS缓冲液,微塑料染毒组按照25mg㊃mL-1的浓度通过尾静脉注射微塑料标准品溶液200μL㊂每隔2d染毒一次,共染毒5次㊂1.11㊀小鼠肝脏样本前处理通过注射1%的戊巴比妥钠200μL将小鼠麻醉,用眼科镊摘取小鼠眼球,收集全血于抗凝采血管中㊂小鼠处死后进行解剖,在冰面上迅速取出肝脏,进行肝脏内微塑料浓度的研究㊂在电子天平上精确称量肝脏质量,取0.5g肝脏组织放入1.5mL离心管中,加入1mL水和不锈钢研磨珠㊂再放入组织匀浆机中设定强度为70Hz,研磨200s㊂研磨完成后,吸取组织匀浆至100目滤网中进行过滤㊂取1mL滤液于1.5mL离心管中,再将离心管放入氮吹仪中,在60ħ条件下氮吹浓缩4h,得到小鼠肝脏样本粉末㊂1.12㊀金核银壳SERS基底对小鼠肝脏内微塑料的检测应用将前处理完成后的小鼠肝脏样本溶于500μL 去离子水中,充分混匀,再将小鼠肝脏样本溶液5μL与20μL Au@Ag NPs溶液充分震荡混匀(稀释5倍)㊂然后滴加在硅片上,干燥后使用拉曼光谱仪检测并收集微塑料标准品的SERS信号㊂2㊀结果(Results)2.1㊀微塑料颗粒透射电子显微镜和粒径表征本实验采用的微塑料标准品是单分散聚苯乙烯微球,粒径为1000nm,浓度为2.5%(m/V)㊂从透射电子显微镜(TEM)结果可以看出,微塑料颗粒分散性良好且尺寸均匀(图1(a))㊂微塑料颗粒的粒径统计柱状图如图1(b)所示,表明微塑料颗粒平均粒径为870.66nm㊂2.2㊀Au@Ag材料的粒径表征Au@Ag采用柠檬酸钠还原法制备,首先使用柠檬酸钠还原氯金酸溶液制备Au NPs作为核心,随后使用柠檬酸钠溶液还原硝酸银,在Au纳米种子表面上沉积银层,形成均匀包裹的银壳㊂通过粒径表征Au NPs和Au@Ag NPs㊂其中Au NPs粒径分布均匀,平均粒径约为(20.51ʃ0.09)nm(图2 (a))㊂Au纳米种子表面均匀包裹的银壳形成后,Au @Ag NPs平均粒径增加到(24.27ʃ0.19)nm(图2(b)),得到粒径分布较为均匀的Au@Ag纳米材料㊂2.3㊀Au@Ag材料的TEM㊁紫外-可见吸收光谱和Zeta电位表征㊀㊀通过TEM表征得到的Au@Ag纳米材料,由图3(a)可知所制备的30nm Au@Ag NPs形貌大小均一且分散性良好㊂㊀第6期王惠桐等:基于表面增强拉曼光谱的微纳塑料肝脏内暴露检测方法研究191图1㊀微塑料的TEM图(a)和粒径统计柱状图(b)Fig.1㊀TEM image(a)and grain size distribution(b)of microplastics图2㊀Au NPs(a)和Au@Ag NPs(b)的粒径统计柱状图Fig.2㊀Grain size distribution of Au NPs(a)and Au@Ag NPs(b)图3㊀Au@Ag NPs的TEM图(a),Au NPs和Au@Ag NPs的紫外-可见光吸收光谱(b)和Zeta电位值(c)Fig.3㊀TEM image(a)of Au@Ag NPs,UV-vis spectrum(b)and Zeta potential(c)of Au NPs and Au@Ag NPs192㊀生态毒理学报第18卷㊀㊀使用紫外-可见吸收光谱对所制备的Au @AgNPs 进行检测㊂金属纳米颗粒的等离子共振峰与纳米材料的尺寸大小㊁形貌及元素组成密切相关㊂如图3(b)所示,Au NPs 的光谱结果基本与文献报道结果[19]一致㊂随着银层在Au 纳米种子表面沉积,紫外-可见吸收光谱峰明显蓝移,谱带强度增加,且Au @Ag NPs 具有双峰的吸收性质,证明金银复合纳米颗粒的形成㊂通过测量Au @Ag 制备过程中各阶段产物的Zeta 电位,辅助证明各阶段产物是否成功制备㊂如图3(c)所示,Au NPs 的Zeta 电位大约为(-27.3ʃ0.96)mV ,随着银壳在Au 纳米表面形成,Au @Ag NPs 的Zeta 电位降为(-43.3ʃ3.94)mV ㊂2.4㊀拉曼光谱对微塑料标准品的检测结果本实验对微塑料标准品进行梯度稀释,制备了一系列微塑料标准品溶液(浓度范围为10~0.1mg ㊃mL -1)㊂分别滴加到硅片上,干燥后进行拉曼光谱检测,结果如图4(a)所示㊂微塑料的拉曼光谱特征峰与文献所报道的数据[20]基本相符,位于1004cm -1的特征峰在0.25mg ㊃mL -1以上都清晰可见㊂对每个样品进行5组检测,然后对拉曼位移1004cm -1的特征峰强度和微塑料标准品浓度的关系进行统计分析,得到拉曼光谱微塑料检测标准曲线(如图4(b)),线性回归方程是:y =161.98+329.64x线性相关系数(r 2)是0.981㊂这些结果表明,1004cm -1处的拉曼光谱强度与微塑料标准品浓度呈现良好的线性关系㊂2.5㊀金核银壳SERS 基底对微塑料标准品的检测结果㊀㊀本实验对微塑料标准品进行梯度稀释,制备了一系列微塑料标准品溶液(浓度范围为5~0.05mg ㊃mL -1),向梯度稀释微塑料标准品溶液中加入离心浓缩后的Au @Ag NPs ,并充分混合,混合均匀后,分别滴加到硅片上,干燥后使用拉曼光谱仪进行检测,采用最大激发功率的30%㊂积分时间为10000ms ㊂对每个样品进行5组检测,记录并保存数据㊂所得结果如图5(a)所示,微塑料的拉曼光谱特征峰与文献所报道的数据[20]基本相符,微塑料特征峰处的拉曼位移为1004cm -1㊂微塑料浓度从5mg㊃mL -1至0.05mg ㊃mL -1,所有特征峰的强度都有所提高㊂根据微塑料在拉曼位移1004cm -1处的峰强度与微塑料溶液浓度拟合曲线,得到SERS 微塑料检测标准曲线(如图5(b)),拟合方程为:y =473539.75-473604.561+(x572961.29)0.41线性相关系数(r 2)是0.992㊂将空白组拉曼强度值加3倍的标准差带回拟合方程,计算得到Au @Ag NPs 检测微塑料的检测限为0.0175mg ㊃mL -1㊂由实验结果可知,该方法制备的Au @Ag NPs 增强效果较好,Au @Ag NPs 可作为SERS 基底用于微塑料的检测㊂2.6㊀金核银壳SERS 基底对小鼠肝脏内微塑料浓度的检测结果㊀㊀肝脏内微塑料浓度的检测结果如图6所示,微塑料的拉曼光谱特征峰与文献所报道的数据[20]基本相符,拉曼位移1004cm -1处可见微塑料特征峰,将微塑料在拉曼位移1004cm -1处峰强度的平均值732.3283代入SERS 微塑料检测标准曲线,计算得出待测样品中的微塑料浓度为0.0987mg ㊃mL -1,由于图4㊀拉曼光谱检测微塑料标准品的光谱(a )及标准曲线(b )Fig.4㊀Raman spectrum (a)and standard curve (b)of microplastics at different concentrations第6期王惠桐等:基于表面增强拉曼光谱的微纳塑料肝脏内暴露检测方法研究193㊀图5㊀表面增强拉曼光谱(SERS )检测微塑料标准品的光谱(a )及标准曲线(b )Fig.5㊀Surface-enhanced Raman spectroscopy (SERS)spectrum (a)and standard curve (b)of microplasticsat different concentrations with Au @AgNPs图6㊀小鼠肝组织悬液的拉曼光谱图Fig.6㊀Raman spectrum of mouse liver spectrum在样品检测过程中加入Au @Ag NPs 导致样品稀释5倍,所以肝组织悬液内微塑料浓度为0.493mg ㊃mL -1㊂检测前0.5g 肝脏样品经前处理后复溶于500μL 去离子水,由此可计算出肝组织内的微塑料质量浓度为0.493mg ㊃g -1㊂因此,以Au @Ag NPs为基底的SERS 可以成功对微塑料肝脏内暴露情况进行检测㊂3㊀讨论(Discussion )传统微纳塑料检测方法通常存在样品预处理程序繁琐,检测时间长,不能定量分析等缺点,Lv 等[21]通过一种以银胶体为活性底物的SERS 方法,克服了液体中微纳塑料检测的局限性,在水环境样本中可以检测到浓度低至40μg ㊃mL -1的微纳塑料㊂在本实验中,以Au @Ag NPs 作为SERS 基底的微纳塑料检测方法,微纳塑料检测限低至17.5μg ㊃mL -1,优于前述检测方法,可见Au @Ag NPs 大大增强了微纳塑料的拉曼信号,使其灵敏度得到大幅度提高㊂同时,本实验也对较小粒径(80nm)的聚苯乙烯微塑料标准品溶液进行了拉曼和SERS 检测,但是在拉曼位移1004cm -1处的拉曼信号的特征峰较弱,说明本检测方法尚存在一定的缺限,对于粒径较小的微纳塑料灵敏度仍然不高㊂Hu 等[22]对SERS 进行了改进,将碘化钾(KI)作为混凝剂和清洁剂,去除Ag NPs 表面的杂质,成功检测到50nm 的微纳塑料㊂因此,在后续实验中,也可增加混凝剂和清洁剂前处理步骤,提高对小粒径微纳塑料颗粒检测的灵敏度㊂目前大部分研究都以检测环境中的微纳塑料为重点,仅有少数研究关注微纳塑料肝脏内暴露的研究,且这些方法也存在局限性㊂Schwabl 等[23]通过傅里叶变换红外(FT -IR)显微光谱法,分析了8名健康志愿者体内粪便样本,结果发现8份粪便样本的微纳塑料检测均呈阳性,共检测到9种塑料类型,尺寸在500nm ~10μm 之间㊂但是FT -IR 显微光谱法存在一些无法避免的问题,其中包括样品的化学预处理步骤会降解微纳塑料并降低其回收率,且样品制备后残留的固体可能会掩盖FT -IR 图像分析过程中的颗粒㊂本研究建立的检测方法减少了过度的前处理步骤,极大地避免检测过程中微纳塑料颗粒的损失㊂另外,Huang 等[24]通过激光红外成像光谱仪和FT -IR 显微光谱法分析了22份痰液样本中的微塑料,发现所有痰液样本中都存在微纳塑料,共检测出微纳塑料21种,大多数微纳塑料粒径小于500μm ㊂但是这种研究方法只能提供微纳塑料的丰度194㊀生态毒理学报第18卷数据,不能对微塑料进行定量分析,且FT-IR显微光谱法灵敏度较低,无法对粒径小于20μm的微纳塑料进行检测㊂Leslie等[25]通过热分解气相色谱-质谱联用法(Pyr-GC/MS)对400份血液样本进行了分析,其中77%的血液样本中存在塑料颗粒,血液中塑料颗粒的总和可量化浓度的平均值为1.6μg㊃mL-1,粒径范围在700~500000nm之间㊂但是Pyr-GC/MS是热分析方法,这种方法会破坏微纳塑料检测样品,且前处理步骤复杂㊂Ragusa等[26]用拉曼显微光谱法对人胎盘中的微纳塑料进行了检测,在4个胎盘中发现了12个微塑料碎片,粒径大小5~10μm不等㊂虽然该研究采用了拉曼分析法,但是没有对其微纳塑料内暴露情况进行定量分析,且检测到的微纳塑料最小粒径仅为5μm㊂综上所述,目前已报道的微纳塑料体内暴露检测方法都有各自的局限性,很难精确评估各器官微塑料暴露水平并进行定量分析㊂本实验则通过构建小鼠微塑料急性暴露模型,经过短时间的急性暴露后,取其肝脏制备组织悬液并进行检测,得到肝组织悬液微塑料浓度为0.493mg㊃mL-1㊂再根据肝脏组织质量和检测溶液体积,计算出肝组织内的微塑料质量浓度为0.493mg㊃g-1㊂从实验结果可以看出, SESRS能够精确定量肝脏微塑料的浓度,且样品前处理步骤简单,同时还避免了传统检测方法灵敏度和准确性较低的缺点,实现微塑料肝脏暴露水平的精确定量分析,为之后人体内的微纳塑料摄入情况的研究提供了新的思路和方法,且为微纳塑料对人体危害的研究提供技术支持㊂通信作者简介:李晓波(1979 ),女,博士,教授,主要研究方向为生态毒理学㊂参考文献(References):[1]㊀Gong J,Xie P.Research progress in sources,analyticalmethods,eco-environmental effects,and control measuresof microplastics[J].Chemosphere,2020,254:126790 [2]㊀Gan Q,Cui J W,Jin B.Environmental microplastics:Classification,sources,fates,and effects on 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R,Manna C,Padha S,et al.Micro(nano)plasticspollution and human health:How plastics can induce car-cinogenesis to humans?[J].Chemosphere,2022,298:134267[9]㊀Prata J C,da Costa J P,Lopes I,et al.Environmental ex-posure to microplastics:An overview on possible humanhealth effects[J].The Science of the Total Environment,2020,702:134455[10]㊀Sridhar A,Kannan D,Kapoor A,et al.Extraction and de-tection methods of microplastics in food and marine sys-tems:A critical review[J].Chemosphere,2022,286(Pt1):131653[11]㊀范玉梅,石佳颖,高李璟.土壤中微塑料的来源及检测[J].化工时刊,2019,33(6):28-31Fan Y M,Shi J Y,Gao L J.The source and detection ofmicroplastics in soil systems[J].Chemical IndustryTimes,2019,33(6):28-31(in Chinese)[12]㊀Yusuf A,Sodiq A,Giwa A,et al.Updated review on mi-croplastics in water,their occurrence,detection,measure-ment,environmental pollution,and the need for regulatorystandards[J].Environmental Pollution,2022,292(Pt B):118421[13]㊀Zhou X,Hu Z W,Yang D T,et al.Bacteria detection:From powerful SERS to its advanced compatible tech-niques[J].Advanced Science,2020,7(23):2001739 [14]㊀Bi L Y,Wang X,Cao X W,et al.SERS-active Au@Agcore-shell nanorod(Au@AgNR)tags for ultrasensitivebacteria detection and antibiotic-susceptibility testing[J].Talanta,2020,220:121397[15]㊀冯艳林,王建霖,宁鑫,等.金核/银壳纳米棒用于癌细胞的表面增强拉曼散射成像及肿瘤活体光谱检测[J].分析化学,2022,50(8):1196-1204Feng Y L,Wang J L,Ning X,et al.Au@Ag core-shellnanorods for surface enhanced Raman scattering imaging。
单细胞凝胶电泳其及光学图像分析(英文)
张炜;代正民;罗明智;齐浩
【期刊名称】《光子学报》
【年(卷),期】2004(33)7
【摘要】采用单细胞凝胶电泳检测DNA损伤度 ,运用光学图像处理软件对彗星试验得到的参数进行图像分析 ,结果表明 :该方法快捷 ,灵敏度高 ,能够较好地应用于DNA损伤度的修复、细胞遗传。
【总页数】3页(P877-879)
【关键词】彗星试验;单细胞凝胶;图像分析
【作者】张炜;代正民;罗明智;齐浩
【作者单位】西北大学光子学与光子技术研究所;陕西师范大学生命科学学院【正文语种】中文
【中图分类】Q632
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2.单细胞凝胶电泳技术检测丙烯酰胺亚急性中毒大鼠的单细胞DNA损伤 [J], 杨淑芸;李国良;付正英;张引国;张金波
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a r X i v :h e p -l a t /9608103v 1 20 A u g 19961Quenched Hadron Spectroscopy with Improved ActionsWolfgang Bock aaCenter for Computational Physics,University of Tsukuba,305Ibaraki,JapanA variety of different combinations of improved gluon and fermion actions is tested for quenched hadron spectroscopy.1.INTRODUCTIONThe improvement of the lattice QCD action has become recently a main focus of research in lattice field theory.Improved actions for lattice QCD are designed to remove lattice-spacing artifacts in nu-merical estimates of physical observables.This allows to conduct the numerical calculations on much coarser and smaller lattices and thereby to substantially reduce the simulation costs.In this contribution a variety of different combina-tions of gauge and fermion actions is tested for quenched hadron spectroscopy.For the gluon ac-tion we used the tadpole improved L¨u scher-Weisz (T-LW)[1–3]and the Iwasaki (IW)action [4].The LW action has been obtained by extending Symanzik’s perturbative improvement program to lattice gauge theories,demanding O (a 2)im-provement of on-mass-shell quantities [1].The use of tad-pole improvement is essential to en-hance the convergence of the perturbative expan-sion and extend perturbation theory to larger dis-tances [2].The IW action on the contrary is a renormalization group improved action.Scaling tests carried out recently for both models have been very encouraging [3,5,6].The fermion ac-tions which we shall consider in this contribution are the Sheikholeslami-Wohlert (SW)action [7],the D234action [8]and for comparison also the standard Wilson action (W).Symanzik improve-ment of the Wilson action leads to the SW action which eliminates the cut-offeffects in on-mass-shell quantities to order O (a ).With the D234action one attempts to go even one step beyond the O (a )improvement and to eliminate partially some of the cut-offeffects to O (a 2).Also in the case of the improved fermion actions it is essentialto couple the fermions to a ”tadpole improved”(T)lattice link variable [2].We computed the hadron spectrum for the following five combina-tions of improved gluon and fermion actions:T-LW&W,T-LW&T-SW,T-LW&T-D234,IW&T-SW and IW&T-D234.2.DETAILS OF THE SIMULATION In order to be able to compare the results ob-tained with the different gluon actions we have conducted the simulations for the T-LW and IW actions at the critical βof the deconfining phase transition for N t =2[6].We performed the simu-lations on a 6316lattice using a standard Hybrid Monte Carlo algorithm.For the determination of the hadron spectrum we generated about 500configurations,which were separated by 50tra-jectories.For the inversion of the fermion ma-trix we used the BICG γ5algorithm which differs from the CG algorithm by the insertion of a γ5in the inner products.We find that the BICG γ5is,within the interval m π=0.7-1.0,by a fac-tor 3-4times faster than the BICGstab and by a factor 6-8faster than the CG algorithm.The BICG γ5algorithm is not guaranteed to converge as a division by zero can occur during the iter-ation process.We have however never encoun-tered a breakdown of the algorithm although we performed in total about 2.5105inversions of the fermion matrix.For the determination of the hadron spectrum we implemented the standard correlation func-tions for the π,ρ,a 0,a 1and b 1mesons,the nu-cleon (N)and the ∆,using local operators for the quark field,both at the source and the sink.The meson and baryon propagators have been fitted2Figure 1.The mass ratios m N/mρ(a)and m∆/mρ(b)as a function of mπ/mρ.The T-LW&W,T-LW&T-SW,T-LW&T-D234,IW&T-SW and IW&T-D234data are marked by the filled triangles,open circles,crosses,open trian-gles and squares.The horizontal error bars are dropped as they are smaller than the symbol size. with A M[exp(−m M t)+exp(−m M(T−t))]and A B exp(−m B t).We varied t min systematically and averaged the masses when it was difficult to pick out the best among equally goodfits.The mass spectrum has been determined in the in-terval mπ=0.7-1.5,wherefinite size effects are very small.All correlation functions gave a very clear and stable signal in this pion mass range, expect for the a0,a1and b1channels.We dis-covered however that the signal in those chan-nels improves significantly at larger pion masses, and therefore extended the calculation of the a0,Figure2.The masses mρ,m N and m∆as a function of m2πfor the IW&D234action.a1and b1correlation functions with the IW&T-D234action,and for comparison also with the IW&W action,to somewhat larger pion masses, mπ=1.5-2.0.Apart from the hadron mass spec-trum we also computed the string tensionσwhich we determined from the exponential fall-offof the Polyakov loop correlation function.3.RESULTSInfig.1we have plotted the mass ratios m N/mρ(a)and m∆/mρ(b)as a function of mπ/mρ.Thefilled circles to the left correspond to the physical point and thefilled squares to the right to the heavy quark limit,where mπ/mρ=1 and m N/mρ=m∆/mρ=3/2.The solid lines connecting the two points represent the result of a phenomenological quark model formula derived in ref.[9].The graphs show that the points which correspond to the combinations T-LW&T-SW (open circle),T-LW&T-D234(crosses),IW&T-SW(open triangles)and IW&T-D234(squares) cluster in a narrow strip which is located in both cases above the solid line.The large gap be-tween the standard Wilson action data(filled tri-angles)and all other data reveals very clearly the dramatic effect of the fermion improvement.A naive linear extrapolation of the T-LW&T-SW, T-LW&T-D234and IW&T-D234data infig.1a down to the physical value of mπ/mρleads to a m N/mρvalue which is not too far offfrom the ex-3 Figure3.Mass ratios for the various actions.Thesymbols have the same meaning as infig.1.perimental point(filled circle).The extrapolationof the IW&T-SW data on the other hand resultsin a value that is significantly larger indicatingthat the cut-offeffects are bigger for this partic-ular action.We checked that our data obtainedwith the improved fermion actions are,within er-ror bars,consistent with the standard Wilson ac-tion results which have been obtained during thepast years on a muchfiner and bigger lattices.Using chiral perturbation theory we extrapo-lated the hadron masses mρ,m a,m a1,m b1,m Nand m∆to the chiral limit,mπ→0.To thisextend wefitted the meson mass data m M withm(0)M+c2m2π,where m(0)M designates the mass inthe chiral limit and M=ρ,a0,a1,b1in our case.For the nucleon it is essential to include also aterm in the chiralfit which is cubic in the pionmass,m(0)N+c2m2π+c3m3π.Our results show thatthe coefficient c3depends strongly on the particu-lar action.It is largest for the three combinationsT-LW&T-SW,T-LW&T-D234and IW&T-D234and roughly by a factor two smaller for the othertwo actions[10].In the case of the∆wefittedthe mass data with m(0)∆+c2m2π,as a cubicfitleads to a c3value which is consistent with zero[10].As an example,we plotted infig.2the mρ,m N and m∆data for the case of the IW&T-D234action as a function of m2π.The results of thefitsTable1IW&2.37(15) 1.600(52)m(0)a0/m(0)ρ1.70(10)2.28(14) 1.601(13)are represented in this graph by the solid lines.The ratios of the extrapolated masses,m(0)N/m(0)ρand m(0)∆/m(0)ρare displayed infig.3along with√。