Shock compression of liquid deuterium up to 109 GPa
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上消化道出血(Hemorrhage of upper digestivetract)上消化道出血(Hemorrhage of upper digestive tract) Upper gastrointestinal hemorrhage refers to the above Qu ligament of the digestive tract, including the esophagus, stomach, duodenum, pancreas and biliary diseases caused by bleeding, bleeding caused by 1 and gastrojejunostomy after jejunal lesions. The main symptoms were hematemesis, hematochezia and degree of peripheral circulatory failure, such as improper handling can endanger life. Clinical nursing plays an important role in the process of treatment. To do well the nursing of patients is one of the important measures to promote the improvement of disease, prolong the bleeding cycle and reduce the number of bleeding. 1 condition observation Observation of vital signs in 1.1 15 min observation of 1 vital signs, and do a good job of recording. After the upper gastrointestinal hemorrhage, the patient’s blood pressure decreased, systolic pressure was below 10.6 kPa, and he was in shock state. But in the early stage of hemorrhagic shock, blood pressure can be basically normal due to compensation, and even at a high level, attention should be paid to the fluctuation of blood pressure.1/ 11The pulse of the change is a main sign of observation of shock, shock acceleration shock pulse early, late weak pulse. The shock of upper gastrointestinal bleeding when the temperature can not rise, most of the patients were fever control in shock after general bleeding in 24 h after the fever, the temperature does not exceed 38.5 degrees, sustainable 3 D ~ 5 d, such as body temperature or persistent fever and did not rise to consider re bleeding. The observation of 1.2 hematemesis and melena Hematemesis and melena is a characteristic manifestation of upper gastrointestinal bleeding after upper gastrointestinal bleeding, were black, but not necessarily hematemesis. The bleeding site in the pyloric following may represent only a black, more often with hematemesis in h.. For hematemesis Tan, a kind of coffee. Pay attention to the amount and nature of hematemesis, hematochezia. General stomach blood storage of 250 mL to 300 mL can cause vomiting; stomach blood storage 50 mL ~ 70 mL is black; stomach blood storage 500 mL to 1000 mL, the patient can appear dizziness, palpitations, fatigue, clammy skin and other symptoms, abnormal timely report to the doctor. Observation of 1.3 urine volume The amount of blood loss and the amount of transfusion and blood transfusion were estimated according to the amount of fluid discharged. Thepatient with upper gastrointestinal bleeding could record the amount of vomiting, feces and urine. Pay close attention to the nature and amount of vomit, the nature, frequency and consistency of the stool, estimate the amount of blood loss accurately, and pay attention to the amount of urine and the specific gravity of the urine. If the urine volume is 20 mL to 30 mL per hour, it indicates that the blood pressure can maintain the brain and renal function in the normal range without injury [2]. 1.4 observation of other conditions A large amount of bleeding, blood loss was more, because of the circulating blood volume decreased rapidly, can cause dizziness, palpitation, sweating, nausea, thirst or fainting, bleeding more than 20% can be irritability, apathy, limb cold shock etc.. 1.5 accurately record and analyze the results of the examination to prevent rebleeding The condition of upper gastrointestinal bleeding is easy to be repeated, and the rebleeding should be closely observed after bleeding control. If the patient appears again hematemesis or melena and increased the number of color from black to red, thin, or from yellow to black, unstable blood pressure, pulse, hemoglobin, red blood cell count and hematocrit continues to decline, the3/ 11temperature rise and persistent or back, patients feel irritability, dizziness, palpitation, sweating, thirst so, said again the possibility of bleeding, the doctor should report immediately, actively cooperate with the rescue. Gastric tube drainage was performed to observe the drainage of gastric juice, to observe whether the bleeding stopped, and to record the nature, color and quantity of the drainage fluid.2 nursing 2.1 nursing on admission Notify the physician immediately after the patient is hospitalized, absolute bed rest, placement of the patient supine position, warm, comfort the patients do not have nervous, hematemesis head sideways, oral cleaning haematocele timely, maintain airway patency, necessary oxygen 3. The immediate establishment of circulation channel do effective infusion and transfusion preparation, according to the instructions for routine hemostatic drugs, noradrenaline 8 mg in 150 mL ~ 250 mL orally cold saline, prescribed medication after proper rotation for drugs and physical wounds full contact. 2.2 rapid establishment of venous access In order to facilitate rapid transfusion and transfusion, large numbers of effective venous channels should be established rapidly. The Y type venous indwelling needle can be used, because it has the function of inputting multiplegroups of fluids simultaneously. Before transfusion, dextran or carboxymethyl starch can be used before transfusion, and blood volume can be rapidly increased. Try to import fresh blood. Early transfusion and transfusion should be carried out in the early stage, and appropriate adjustment of speed should be made according to the heart and lung function of the patients in the late stage to prevent excessive pulmonary edema caused by excessive infusion. 2.3 give timely hemostatic drugs Use of cimetidine, pituitrin, batroxobin, hemostatic agent. The use of contraindications should be based on the nature of the drugs during the use of hemostatic agents. Adjust the speed of infusion, for esophageal variceal bleeding patients, available three cavity balloon tube compression for bleeding hemorrhage; acute gastric mucosal damage or peptic ulcer caused by the use of cimetidine intravenous infusion of 400 mL per 6 h ~ 8 h 1 times, or ranitidine infusion of 50 mg, every 6 ~ 8 h h 1; also used famotidine and omeprazole intravenous infusion. 2.4 pay attention to oxygen inhalation, rest and body position Patients with severe condition should cooperate with oxygen inhalation, especially in patients with esophageal variceal bleeding, hypoxia induced hepatic encephalopathy easily.5/ 11Bleeding patients should be quiet in bed, supine position, lower limb elevation 30 degrees, keeping respiratory tract unobstructed, head to one side, to avoid vomiting caused by suffocation. 2.5 strengthen basic nursing Oral care: for patients with oral bleeding have xingchouwei, should be 3 times a day to wash the mouth, to prevent oral infection. Skin care, nursing: frequent stool, stool every time the toilet should be clean, keep the hips clean and dry sheets after pollution timely replacement, to prevent the occurrence of eczema and bedsore.2.6 diet nursing Eating can neutralize gastric acid, protect gastric mucosa, maintain water and electrolyte balance, maintain nutrition, promote intestinal peristalsis, reduce blood pressure and stomach, and reduce nausea and vomiting. The bleeding caused by peptic ulcer stopped for 6 h and then took warm, cold, light and non irritating liquid diet. Liquid diet and water temperature is not prone to overheating, then gradually changed to semi liquid diet, diet, to nutritious digestible food, to eat much food less, later changed to a normal diet, do not eat the salad, crude fiber of vegetables, excitant food, hard food, beverages, such as concentrated juice of chicken soup tea, coffee, broth, etc.; esophageal variceal bleeding stopped after 24 h eating high calorie, high vitamincold liquid diet, sodium and protein intake, avoid inducing and aggravating ascites and hepatic encephalopathy, avoid eating hard and pungent food (such as peanuts, melon seeds, walnuts, apples, fish and chips, etc.) should be chewed, and avoid injury of esophagus mucosa bleeding again. Observation of bleeding volume and maintenance of nutrition by indwelling gastric tube in patients with consciousness disorder. But it should be noted that bleeding active period should be fasting. 2.7 psychological nursing The life of patients suffering from gastrointestinal hemorrhage is threatened, resulting in fear, anxiety and other bad emotions. Therefore, nurses should take the initiative to care, comfort the patients to understand the reasons for the patients and their families have fear and worry through communication, to strengthen the patient and family health and psychological guidance, make patients and their families emotional stability, treated in the open, calm mood. The rescue work should be quickly without fuss, to explain the examination and treatment work, remove blood stains, dirt, and keep warm, with the patient, try to meet the requirements of patients, enhance their confidence in overcoming the disease.3 health guidance To the family education some of the disease7/ 11knowledge, to have a certain understanding of the treatment process, families and assist doctors to cooperate to solve some practical problems; patients and family members of the church to identify early signs of bleeding and emergency measures appear, hematemesis or melena should rest in bed, keep quiet, reduce physical activity; help to master etiology the disease prevention and treatment knowledge, in order to reduce the risk of re bleeding; maintain a good attitude and optimistic spirit, the correct treatment of the disease, Reasonable arrangements for life, enhance physical fitness, should quit smoking and drinking, under the guidance of the doctor medication, do not use their own prescriptions, careful use of certain drugs. In short, upper gastrointestinal bleeding, acute onset, rapid change is dangerous, causing hemorrhagic shock and circulatory failure and endanger life, such as the correct diagnosis, effective treatment and nursing of hemostasis carefully, can make the patient through, improve the cure rate and reduce the mortality rate, so as to achieve the purpose of rehabilitation. Upper gastrointestinal hemorrhage nursing according to internal medicine and this system disease general nursing routine. [observation] 1. observed blood pressure, body temperature, pulse, breathing changes. 2. the blood pressureand pulse pressure were measured every 15 to 30min during the period of massive hemorrhage. The patients were monitored by ECG and blood pressure monitor. 3. observation of consciousness, peripheral circulation, urine volume, hematemesis and hematochezia color, quality and quantity. 4. have dizziness, palpitation, cold sweat and other shock performance, timely report physician symptomatic treatment and record. [symptomatic care] (1) bleeding period nursing 1. absolute bed rest until bleeding stop. 2. patients who have irritability are given sedatives, and patients with portal hypertensive hemorrhage are cautious to use sedatives when they are agitated.3. patiently and meticulously do the interpretation work, comfort and care for the suffering of patients, to eliminate tension, fear.4. pollution clothing should be replaced at any time, in order to avoid bad stimulation.5. rapid establishment of venous access, as soon as possible to supplement the blood volume, with 5% glucose saline or plasma substitutes, a large amount of bleeding should be timely blood preparation, blood preparation, preparation of double balloon three cavity tube reserve.6. pay attention to keeping warm. (two) according to the condition of nursing care of 1. patients of hematemesis or9/ 11lateral decubitus semirecumbentposition, prevent aspiration.2. rows of gastric tube irrigation, should observe whether there is no new bleeding. [general care] 1. oral care bleeding period fasting, 2 times a day to clean the mouth. Hematemesis should always good oral care to keep the mouth clean, odorless.2. nursing stool stool frequency frequently, every time the toilet should be clean, keep the hips clean and dry, to prevent the occurrence of eczema and bedsore.3. diet nursing fasting during bleeding period; after bleeding stop, give cold warm liquid, semi fluid and digestible soft diet according to the order; after 3D, the patients who have no bowel movement after hemorrhage are careful to use laxatives.4. the use of disaccate three cavity tube compression therapy, reference disaccate three cavity tube nursing.5., the use of special drugs, such as Shi Ning, the posterior pituitary gland, should strictly grasp the drip speed should not be too fast, such as abdominal pain, diarrhea, arrhythmia and other side effects, should promptly report physician treatment. [health guidance] 1. keep good mood and optimism, treat disease correctly. 2. pay attention to diet hygiene, reasonable arrangement of work and rest time. 3. appropriate physical exercise, enhance physical fitness. 4. ban smoking, strong tea, coffee and so on, thestomach has stimulating food. 5. pay attention to diet hygiene and pay attention to work and rest in good season. 6. some may induce or aggravate symptoms of ulcer disease, even cause complications should avoid using drugs such as salicylic acid, reserpine, baotaisong. There are 1. diagnosis upper digestive tract bleeding caused by primary disease, such as peptic ulcer, cirrhosis, chronic gastritis and stress lesions; 2. hematemesis and melena (or); 3. different degrees of bleeding can occur when the corresponding performance, the light can be asymptomatic, may have serious hemorrhagic shock; 4. fever; 5. azotemia; 6. emergency endoscopy can find out blood.11/ 11。
Ultrafast transformation of graphite to diamond: An ab initio study of graphite under shock compressionChristopher J. Mundy, Alessandro Curioni, Nir Goldman, I.-F. Will Kuo, Evan J. Reed, Laurence E. Fried, and Marcella IanuzziCitation: The Journal of Chemical Physics 128, 184701 (2008); doi: 10.1063/1.2913201View online: /10.1063/1.2913201View Table of Contents: /content/aip/journal/jcp/128/18?ver=pdfcovPublished by the AIP PublishingArticles you may be interested inLaser-induced versus shock wave induced transformation of highly ordered pyrolytic graphiteAppl. Phys. Lett. 106, 161902 (2015); 10.1063/1.4918929Molecular dynamics simulations of shock compressed heterogeneous materials. II. The graphite/diamond transition case for astrophysics applicationsJ. Appl. Phys. 117, 115902 (2015); 10.1063/1.4914481Ab initio study of shock compressed oxygenJ. Chem. Phys. 132, 154307 (2010); 10.1063/1.3402497AB INITIO MOLECULAR DYNAMICS SIMULATIONS OF WATER UNDER STATIC AND SHOCK COMPRESSED CONDITIONSAIP Conf. Proc. 955, 443 (2007); 10.1063/1.2833091Towards controlled production of specific carbon nanostructures— a theoretical study on structural transformations of graphitic and diamond particlesAppl. Phys. Lett. 79, 63 (2001); 10.1063/1.1382852Ultrafast transformation of graphite to diamond:An ab initio study of graphite under shock compressionChristopher J.Mundy,1,a͒Alessandro Curioni,2Nir Goldman,3I.-F.Will Kuo,3Evan J.Reed,3Laurence E.Fried,3and Marcella Ianuzzi41Chemical and Materials Science Division,Pacific Northwest National Laboratory,Richland,Washington99352,USA2IBM Research,Zurich Research Laboratory,CH-8803Ruesschlikon,Switzerland3Chemistry,Materials,Earth and Life Sciences,Lawrence Livermore National Laboratory,Livermore,California94550,USA4Paul Scherrer Institut,Winterthurerstrasse190,CH-5232PSI,Villigen,Switzerland͑Received16November2007;accepted1April2008;published online8May2008͒We report herein ab initio molecular dynamics simulations of graphite under shock compression inconjunction with the multiscale shock technique.Our simulations reveal that a novel short-livedlayered diamond intermediate is formed within a few hundred of femtoseconds upon shock loadingat a shock velocity of12km/s͑longitudinal stressϾ130GPa͒,followed by formation of cubicdiamond.The layered diamond state differs from the experimentally observed hexagonal diamondintermediate found at lower pressures and previous hydrostatic calculations in that a rapid bucklingof the graphitic planes produces a mixture of hexagonal and cubic diamond͑layered diamond͒.Direct calculation of the x-ray absorption spectra in our simulations reveals that the electronicstructure of thefinal state closely resembles that of compressed cubic diamond.©2008AmericanInstitute of Physics.͓DOI:10.1063/1.2913201͔INTRODUCTIONDespite being an area of intense research,the phaseboundaries and electronic properties of elemental carbon atextreme pressures and temperatures͑e.g.,10–100s of GPaand1000s of K͒are relatively poorly known.Diamond an-vil cell experiments have been used to study the transforma-tions of graphite under static compression at extreme condi-tions of temperature and pressure.1,2Shock compressiondynamically strains the sample in a uniaxial direction,whilesimultaneously heating the sample.Shock compression ex-periments can achieve nanosecond temporal resolution,andare thus well suited to study time-dependent phenomena.Shock compression experiments up toϳ20GPa have ob-served a martensitic phase transformation from graphite todiamond,3where the graphitic planes slide to form a hexago-nal diamond,which,in turn,forms a cubic diamond.Thetransition from graphite to diamond was observed to occur in10ns for a20GPa shock.Shock Hugoniot parameters forgraphite to diamond transitions have been measured up to120GPa using gas gun experiments.4͑The Hugoniot is the locus of thermodynamic states accessible by a shock.͒Laser-induced shock experiments have been used to study the melt-ing curve of diamond to significantly higher pressure condi-tions͑up to2000GPa͒.5However,experimental techniqueshave only recently been developed to perform in situ studiesof chemical transformations in shocks.6–8Molecular andatomic scale information are difficult to experimentally ob-tain,and theoretical studies are necessary in order to developsimple chemical pictures for the high pressure-temperature behavior of the phase transformations of carbon.A number of thermodynamic equilibrium simulations of carbon at extreme pressures and temperatures have been per-formed,where the pressure and temperature of the system are preset rather than simulating the numerous thermody-namic states induced by shock compression.Several studies have investigated the solid/liquid phase boundaries of carbon at high pressures and temperatures using both empirical9,10 and ab initio11,12potentials.Relatively few studies have in-vestigated the atomistic features of the martensitic phase transition of graphite to diamond.A previous density func-tional theory͑DFT͒study of hydrostatic constant pressure compression found that the sliding of graphite planes into an orthorhombic phase preceded the formation of diamond.13,14 It has been postulated that a layered diamond phase could be formed by direct buckling of hexagonal graphite without plane sliding at pressures above120GPa.13,14It was con-cluded that the experimental observation of this phase was very unlikely.These studies differ from shock compression experiments in that the simulations arefixed at a single state point,whereas shock compression causes a material to visit numerous thermodynamic states.An additional key differ-ence is that the stress in these simulations is hydrostatic, unlike shock waves,which contain regions of highly nonhy-drostatic stress due to the uniaxial nature of planar shock compression.Until recently,it has been extremely difficult to obtain a clear theoretical picture of chemistry behind shock fronts be-cause direct simulation of shock compression can require tens of millions of particles.15One empirical potential has been developed for the study of shock-induced melting of diamond,16although the parametrization of such potentialsa͒Electronic mail:chris.mundy@.THE JOURNAL OF CHEMICAL PHYSICS128,184701͑2008͒0021-9606/2008/128͑18͒/184701/6/$23.00©2008American Institute of Physics128,184701-1for high pressure carbon is still an active area of research.9,10 In order to accurately model the breaking and forming of chemical bonds behind shock fronts,we are generally re-quired to use DFT.Molecular dynamics͑MD͒calculations using DFT,however,are limited to only tens to hundreds of particles due to the extreme computational cost.This pre-cludes making a direct one-to-one comparison between simulations and shock compression experiments,where the nonhydrostatic conditions present in the steady shock front can produce novel intermediate species and mechanisms.In particular,we are interested in determining a molecular level picture of the graphite to diamond phase transformation in-duced by shock loading.Thus,a computational capability to access both electronic states and information on chemical bonding,while capturing the nonhydrostatic nature of a steady shock and the concomitant MD,is necessary to elu-cidate chemical processes at extreme pressures and temperatures.The multiscale shock technique17–20͑MSST͒is a simu-lation methodology based on the Navier–Stokes equations for compressibleflow.Instead of simulating a shock wave within a large computational cell with many atoms,15the MSST computational cell follows a Lagrangian point through the shock wave as if the shock were passing over it. This is accomplished by time-evolving equations of motion for the atoms and volume of the computational of cell to constrain the stress in the propagation directionxxϵp to the Rayleigh line and the energy of the system to the Hugoniot energy condition.17–19In the case of a shock,conservation of mass,momentum,and energy across the shock front leads tothe Hugoniot relation E−E0=12͑p+p0͒͑v0−v͒,where E is theenergy and v is the volume.A subscript0refers to the pre-shocked state,while quantities without subscripts refer to the postshocked state.The Rayleigh line p−p0=U20͑1−0/͒͑where U is the shock velocity andis the density͒describesthe thermodynamic path connecting the initial state of the system to itsfinal͑Hugoniot͒state.For a given shock speed, these two relations describe a steady planar shock wave within continuum theory.By constraining the MD system to obey these relations,MSST enables simulation of the shock wave with significantly fewer atoms and,consequently,with significantly smaller computational cost.MSST has been shown to accurately reproduce the sequence of thermody-namic states throughout the reaction zone of shock com-pressed explosives with analytical equations of state.19Lin-ear scaling of computational work with simulation duration has enabled simulation lengths of up to0.2ns of tight-binding ab initio MD simulations of shock compressed nitromethane.20In this study,we present large scale ab initio DFT MD simulations of the transformation of graphite to diamond un-der shock compression normal to the basal planes.We study significantly higher longitudinal shock stress than previous experiments.3Wefind that the martensitic phase transforma-tion of graphite to diamond occurs much more rapidly as a result.We observe a novel mechanism for the phase trans-formation where the graphitic planes buckle directly,instead of sliding and forming an orthorhombic statefirst.13,14We identify this new intermediate as a layered diamond state,which is a mixture of hexagonal and cubic diamond.We thencalculate the x-ray absorption spectra͑XAS͒of the variousstages of our simulations and determine that the end state ofthe shock compression simulation has a diamondlike elec-tronic configuration.Our results provide a detailed atomicpicture from DFT of the chemistry behind shock fronts ingraphite for thefirst time.SIMULATION DETAILSWe have used Car–Parrinello͑CP͒and Born–Oppenheimer͑BO͒MD in conjunction with MSST to ensureaccurate simulation of the shock induced thermodynamicstates.We employed an optimized version of the CPMDcode21,22for the Blue Gene/L supercomputer at LawrenceLivermore National Laboratory.Four independent simula-tions using the CPMD software package21on360carbon at-oms in conjunction with the MSST method were performed.We performed two Born–Oppenheimer͑BO1,2͒calculations utilizing spin restricted DFT,and CPMD simulations23usingboth spin restricted and unrestricted DFT.A plane-wave cut-off of120Ry and the Perdew–Burke–Ernzerhof exchangeand correlation functional24was used for the BO simulations,although a smaller cutoff of90Ry was found to convergethe stress tensor and total energy for the CP simulations.Cutoffs were based on an uncompressed reference supercell.Subsequent shock compression yields a higher effective cut-off.We found the results for the spin unrestricted and spinrestricted CP calculations to be nearly identical for both andconsequently,only the spin restricted CP simulation is re-ported herein.The interaction between core and valenceelectrons are described by Martins–Troullier pseudo-potentials.25An initial supercell͑in cubic angstroms͒of hex-agonal graphite with size of20.10ϫ12.75ϫ12.30,corre-sponding to experimental graphite lattice parameters,wasused in conjunction with⌫-point sampling of the Brillouinzone.All calculations were performed on four midplanes ͑4096CPUs͒of the Blue Gene/Light supercomputer at LLNL.To compute the XAS spectra,we have used the all-electron half-hole transition potential method with Gaussian and augmented plane-wave treatment of DFT as imple-mented in CP2K.26,27For this calculation,we have used a 6-311G**all-electron basis set for carbon.28In order to investigatefinite size effects,we have con-ducted MSST simulations using the classical potential forcarbon from the work of Tersoff.30The resulting equations ofstate for system sizes of360,2880,and23040carbon atoms TABLE I.Table of simulation parameters andfinal thermodynamic states three calculations performed with different number of atoms͑N͒utilizing the Tersoff potential͑Ref.30͒for carbon in conjunction with the MSST at a shock speed of12km/s.The initial densities were identical to those per-formed with DFT interaction potentials.All three simulations were run for 100ps with a time step of0.1fs.N=360N=2880N=23040T final͑K͒491849814978P xx͑GPa͒130130130final͑g/cc͒ 3.5 3.6 3.6184701-2Mundy et al.J.Chem.Phys.128,184701͑2008͒are shown in Table I .Given the insensitivity of the thermo-dynamic end states to system size using the Tersoff potential,system size effects are unlikely to be present in our DFT simulations.The MSST simulations with the Tersoff poten-tial yielded an amorphous ͑e.g.,noncrystalline ͒state upon shock compression,unlike the diamond phase obtained from DFT.Consequently,we have omitted discussion of its result-ing structural parameters and molecular configurations.RESULTS AND DISCUSSIONWe chose a shock speed of 12km /s in order to produce a shock strong enough to see plastic deformations,and see chemistry on computationally accessible time scales.Our simulations using shock velocities under 12km /s did not yield a diamond phase on the time scale of the simulation ͑e.g.,5–10ps ͒.Simulation parameters for the DFT calcula-tions and final thermodynamic states including equation of state ͑EOS ͒calculations 29fit to experimental results are re-corded in Table II .We achieved longitudinal stresses in the shock propagation direction of ϳ134–140GPa in all three simulations.The total stresses ͑stress tensor trace ͒at the end of the simulations were 83–95GPa.The nonhydrostatic stress tensor indicates that full plastic relaxation of stress to a hydrostatic state has not yet occurred after 1ps of simulation and the simulation has not reached a final thermodynamic state.As a result of the Rayleigh line constraint and the high density of diamond relative to graphite,we expect the simu-lated pressures,temperatures,and densities to be below those of the EOS models in Table II which provide final shock states only.The time evolution of the thermodynamic prop-erties of the shock compressed graphite simulation are shown in Fig.1.After less than 200fs,the simulations all experienced a rise in temperature and pressure followed by a plateau,and second rise plateau after an additional 100fs.This is due to phase transformations and a rearranging of the chemical bonds of the system,discussed below.Shock experiments performed on graphite up to 20GPa have suggested that the transformation to the diamondlikestate is martensitic 3under the pressures studied,and occurs on a roughly nanosecond time scale.Our study,at 130GPa,is close to the melting line of diamond.Thus,a change in mechanism to a nonmartensitic transformation with an amor-phous intermediate is conceivable.An order parameter for tetrahedral configurations 31provides insight into the time evolution of the graphite to a cubic diamond ͑perfectly tet-rahedral state ͒phase transition.The order parameter contains an angular part and a distance part.The angular part S g is defined asS g =332͚j =13͚k =j +14ͩcos j ,k +13ͪ2,͑1͒where j ,k is the angle subtended between the j th and k thbonds.The distance part of the order parameter is defined asS k =13͚k =14͑r k −r ¯͒24r ¯2,͑2͒where r k is the radial distance from the central atom to thek th peripheral atom,r ¯is the arithmetic mean of the fourradial distances,and 13is a normalization factor.We consid-ered the total value order parameter S tot =S g +S k here.For a random configuration of bonds ͑e.g.,a liquid or amorphous solid ͒,S tot yields values of 0.25or greater.31For diamond,the order parameter is 0.We computed the initial value of S tot for graphite to be ϳ0.2.Consequently,we expect the value of S tot to decrease monotonically if our simulations exhibit a martensitic phase transformation.A nonmartensitic phaseTABLE II.Simulation parameters and final thermodynamic states for all three simulations.An electronic mass of 25a.u.was used for the CP runs.The EOS result is based on a fit to experiment ͑Refs.4and 29͒.The differ-ence averages of sp 2and sp 3percentages for the BO 2run is likely due to its short trajectory.Running averages of sp 2and sp 3fractions have been exam-ined and indicate that trajectories from all simulations are converging to the same values.BO 1BO 2CP EOS ͑Final state ͒Cell mass ͑a.u.͒7ϫ10717ϫ10717ϫ107N/A Time step ͑fs ͒0.0970.0970.012N/A Wavefunction cutoff ͑Ry ͒12012090N/A Wavefunction convergenceTolerance ͑a.u.͒5ϫ10−51ϫ10−6N/A N/A T final ͑K ͒4084.24058.83351.25300P xx ͑GPa ͒139.8134.4136.4150P tot ͑GPa ͒94.884.783.4N/A final ͑g/cc ͒ 3.9 3.8 3.8 4.2sp final 2͑%͒183019N/A sp final 3͑%͒827081N/AFIG.1.Time evolution of the thermodynamic states induced by the 12km /s shock velocity.The results are shown for the BO 2simulation.The thermo-dynamic profiles of all three simulations were nearly identical.184701-3Ultrafast transformation of graphite to diamond J.Chem.Phys.128,184701͑2008͒transformation would exhibit an increase to a value equal to or greater than 0.25if a liquidlike intermediate is formed first,followed by a decrease to 0.Plots of S tot for all three DFT simulations clearly show a martensitic phase transformation ͑Fig.2͒.S tot decreases rap-idly and roughly monotonically to near-zero values as the graphite compresses to diamond.This indicates the absence of an amorphous intermediate state.The nonzero endpoints indicate that the final configurations are not perfectly tetra-hedral.It is interesting to note the ϳ100fs plateau observed for all three simulations,similar to Fig.1.This is due to the transient layered diamond phase,which is discussed below.All three simulations yield extremely similar results for the structural variation as a function of time.Thus,the observed martensitic transformation is reproducible with different simulation protocols ͑see Table II ͒.Our results suggest that the mechanism of the graphite to diamond remains marten-sitic between 20and 130GPa,although the time scale drops by three orders of magnitude.The CP simulation phase trans-formation is in good agreement with the BO simulations de-spite the electron heating issues in the CP simulation that cause the temperature to drift by ϳ180K from the target ͑Hugoniot ͒energy and the BO simulation temperature.In order to create a structural picture for the changes that occur during the shock compression,we have calculated the wide XAS ͑WAXS ͒͑Fig.3͒.The WAXS intensities I ͑Q ͒are calculated using the following formula:32I ͑Q ͒=͚ijf C 2͑Q ͒exp ͑i Q ·r ij ͒,͑3͒where f C ͑Q ͒are the standard carbon atomic form factors.33We have used an x-ray energy of 37.45keV for all calculations.1For the first few hundred femtoseconds of each simulation,the graphitic planes stay relatively intact,and weobserved single peaks at ϳ6°and 9.5°,and a doublet cen-tered at ϳ16°.This corresponds nearly exactly to experimen-tal results for compressed graphite.1Comparison of the WAXS of the middle plateau of our simulations to that of hexagonal diamond 14shows a mixture of hexagonal and cu-bic diamond spectra.Instead of a doublet at ϳ9°,we found a single peak,similar to what is found for cubic diamond.Our computed spectrum does exhibit the hexagonal diamond sin-glets at ϳ10°and 12.5°.However,the doublet found in hex-agonal diamond at ϳ16°appears to be coalescing into the single peak found in cubic diamond.This mixed cubic/hexagonal diamond phase is similar to what is found in static simulations of graphite compressed to much lower conditions.13The graphite layers likely buckle after rapid compression,allowing for sp 3-sp 3bonds to occur between the basal planes.14This represents a novel mechanism for the formation of cubic diamond from shock compression.The hexagonal diamond intermediate seen at lower shock velocities 3is not observed under the strong shock loading studied here.In all three DFT simulations,the layered dia-mond phase transforms to cubic diamond within ϳ100fs.FIG.2.Evolution of the tetrahedral order parameter as a function of time.The dashed curve corresponds to the BO 1simulation and the solid curve to the BO 2simulation.The dotted curve is the result from the CP simulation.The difference in the time scale to fully compress the simulation cell is dictated by the fictitious cell mass ͑see Table I ͒.Graphite corresponds to a value of 0.2and pure cubic diamond to a value of 0.A nonmartensitic transition to a liquid phase would have shown an increase in the value of the order parameter to 0.25or greater,followed a monotonic decrease to0.FIG.3.Wide angle x-ray scattering intensities of the compressed states ofgraphite.All results shown are from BO 1͑black curves ͒.The top panel ͑graphite ͒is averaged from zero to 300fs,with comparison to experimental results ͑dotted curve ͒at 3GPa ͑Ref.1͒.The middle panel ͑layered diamond ͒is averaged from 300to 500fs,shown with comparison to simulations for hexagonal diamond ͑Ref.14͒͑dotted curve ͒.The missing doublet at ϳ9°and the coalescence of peaks at ϳ16°indicates a mixture of hexagonal and cubic diamond phases.The bottom panel ͑cubic diamond ͒is averaged over the remainder of the simulation,with comparison made to simulations at 20GPa ͑Ref.14͒͑dotted curve ͒.184701-4Mundy et al.J.Chem.Phys.128,184701͑2008͒Snapshots of the three different phases found in our simula-tions ͑graphite,layered diamond,and cubic diamond ͒are shown in Fig.4.In addition to the above structural information,ab initio calculations also yield insight into the electronic states,which are not obtainable from empirical interaction poten-tials.In particular,we wish to investigate the effects of strong shock compression on the time evolution of the elec-tronic structure of the system.Although the final state of our simulation appears to be structurally diamondlike,this does not guarantee the existence of a diamondlike ͑insulating ͒electronic configuration.Recent advances in the techniques for computing XAS from ab initio calculations using all-electron methods allow us to directly compute the spectro-scopic signature of the final state achieved in our simulation.The XAS for our periodic supercell are shown in Fig.5.Our calculated XAS spectrum for graphite at 300K ͑top panel ͒shows a near-edge feature at ϳ287eV,which corre-sponds to a 1s to *transition,indicative of a -bonding network.1The higher energy remainder of the spectrum cor-responds to 1s to *transitions ͑-bonding network ͒.How-ever,the XAS spectrum of the final state of our simulation ͑middle panel,black curve ͒has a marked the absence of the *transition and an enhanced *part of the spectrum.This is expected for a bonded network structure such as cubic diamond.In addition,the spectrum exhibits a diffuse maxi-mum at ϳ290–300eV,a minimum at ϳ303eV,and a sec-ond maximum at ϳ306eV.The minimum at ϳ303eV very closely corresponds to the experimentally measured “second band gap”signature of a diamondlike material.34For refer-ence,we have computed the XAS of compressed cubic dia-mond in a hydrostatic state at the same density as our final compressed state ͑bottom panel ͒.We observe that the posi-tion of the second band gap of the hydrostatically com-pressed cubic diamond is in good agreement with both ex-periment and the end state of our simulations.In addition,we have also isolated the XAS of the simu-lation end state due to the sp 2-only carbon centers ͑middle panel,dashed curve ͒.Due to the significantly lower concen-tration of sp 2-only sites ͑Table II ͒,this normalized spectrum was then scaled by a factor of 0.6in order to be visible on the same scale.The *signal of this compressed state is blueshifted relative to the *signal of the uncompressed graphite.This blueshift can be seen,although in a less dra-matic,in the experiment 1and is likely due to the effects of the pressure applied normal to the basal planes.We also ob-serve a *transition at ϳ288eV and a diminished -bonding network.CONCLUSIONWe have used ab initio MD to provide a simple atomistic picture for the shock-induced phase transformation of graph-ite to diamond.Our results indicate that the transition is mar-tensitic at 130GPa,which is consistent with experiments at 20GPa.3This suggests that the mechanism may remain mar-tensitic from 20to 130GPa along the shock Hugoniot.However,we note two significant differences in our findings.First,we find that the graphite to diamond transition occurs four orders of magnitude faster at 130GPa than at the ex-perimental pressure of 20GPa ͑1ps versus 10ns ͒.Second,we observe a completely different transformation mechanism than found in hydrostatic ͑not shock ͒simulations.We find that a new intermediate layered diamond phase is formed without plane sliding,through buckling of the basal planes.From examination of Table II ,it is clear that the plastic re-laxation of stress is not complete at the final simulationtimeFIG.4.Snapshots of the BO 1simulation at various points during shock compression.The circled region in the layered diamond snapshot ͑b ͒corre-sponds to a likely hexagonal diamondregion.FIG.5.Calculated XAS of ͑top panel ͒graphite at 300K,͑middle panel ͒our final compressed state,͑bottom panel ͒hydrostatically compressed cubic dia-mond at the same density as the final compressed state.The XAS of graphite shows the *pre-edge intensity at ϳ285eV and the *intensity at ϳ295eV.The middle panel shows the XAS spectrum averaged over 200carbon centers.The dotted curve in the middle panel is the scaled partial XAS spectra of the sp 2-only carbon centers.This shows that the observed phase is more closely related to diamond than graphite.184701-5Ultrafast transformation of graphite to diamond J.Chem.Phys.128,184701͑2008͒of1ps even though the phase transition to diamond is nearly complete at this time.Our computed XAS spectra indicate that the end state of our simulation contains an electronic signature of cubic diamond.However,due to the elevated temperatures and pressures compared to the experiment,1the features of our spectrum are likely broadened.In addition, calculation of the spectrum from sp2-only sites in the system indicate trace amounts of-bonds. ACKNOWLEDGMENTSThis work was performed under the auspices of the U.S. Department of Energy by University of California LLNL un-der Contract No.W-7405-Eng-48.We would like to thank Tony Van Buuren,Trevor Willey,Dave Erskine,Jon Eggert, and Juerg Hutter for illuminating discussions.We also grate-fully acknowledge Mike McCoy and Dale Nielsen of the Center for Applied Scientific Computing for generous travel funds for A.C.and for supporting this research.1W.L.Mao,H.K.Mao,P.J.Eng,P.T.Trainor,M.Newville,C.C.Kao,D.L.Heinz,J.Shu,Y.Meng,and R.J.Hemley,Science302,425͑2003͒.2F.Bundy,W.Bassett,M.Weathers,R.Hemley,H.Mao,and A.Gon-charov,Carbon34,141͑1996͒.3D.J.Erskine and W.J.Nellis,Nature͑London͒349,317͑1991͒;J.Appl.Phys.71,4882͑1992͒.4W.H.Gust,Phys.Rev.B22,4744͑1980͒.5S.Brygoo,E.Henry,P.Loubeyre,J.Eggert,M.Koenig,B.Loupias,A.Benuzzi-Mounaix,and M.L.Gloahec,Nat.Mater.6,274͑2007͒.6Y.M.Gupta,Y.A.Gruzdkov,and G.I.Pangilinan,Chem.Phys.Lett.283,251͑1998͒.7M.D.Knudson,K.A.Zimmerman,and Y.M.Gupta,Rev.Sci.Instrum.70,1743͑1999͒.8P.A.Rigg and Y.M.Gupta,J.Appl.Phys.93,3291͑2003͒.9L.M.Ghiringhelli,J.H.Los,E.J.Meijer,A.Fasolino,and D.Frenkel, Phys.Rev.B69,100101͑2004͒.10L.M.Ghiringhelli,J.H.Los,E.J.Meijer,A.Fasolino,and D.Frenkel, Phys.Rev.Lett.94,145701͑2005͒.11A.Sorkin,J.Alder,and R.Kalish,Phys.Rev.B74,064115͑2006͒. 12A.A.Correa,S.A.Bonev,and G.Galli,Proc.Natl.Acad.Sci.U.S.A. 103,1204͑2006͒.13S.Scandolo,M.Bernasconi,G.L.Chiarotti,P.Focher,and E.Tosatti, Phys.Rev.Lett.74,4015͑1995͒.14F.J.Ribeiro,P.Tangney,S.G.Louie,and M.L.Cohen,Phys.Rev.B72, 214109͑2005͒.15K.Kadau,T.C.Germann,P.S.Lomdhal,and B.L.Holian,Science296, 1681͑2002͒.16S.V.Zybin,M.L.Elert,and C.T.White,Phys.Rev.B66,220102͑2002͒.17E.J.Reed,L.E.Fried,and J.D.Joannopoulos,Phys.Rev.Lett.90, 235503͑2003͒.18E.Reed,L.E.Fried,M.R.Manaa,and J.D.Joannopoulos,in Chemistry at Extreme Conditions,edited by M.Manaa͑Elsevier,New York,2005͒. 19E.J.Reed,L.E.Fried,W.D.Henshaw,and C.M.Tarver,Phys.Rev.E 74,056706͑2006͒.20E.J.Reed,M.R.Manaa,L.E.Fried,K.R.Glaesemann,and J.D. 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doi: 10.3969/j.issn.2095-4468.2022.04.202基于蒸气压缩制冷的器官灌注系统的设计与实验研究金斌辉1, 2,杜杰1,刘宝林*1(1-上海理工大学生物系统热科学研究所,上海 200093;2-上海理工大学能源与动力工程学院,上海 200093) [摘 要] 针对器官低温保存设备在长距离运输过程中由于储冷量有限,内部温度易升高进而影响器官保存质量的问题,本文采用主动式制冷设计了一款器官灌注系统,建立了设备基本模型,并进行系统测试。
实验结果表明,温控区间为(2.5±2) ℃时,测试5 h 后肾器官表面从37 ℃降至8 ℃并维持基本恒定。
测试至第14 h 后,储冷盒温度升至4.5 ℃附近,制冷系统开启,平均降温时间0.46 h ,平均升温时间1.3 h 。
器官储藏室平均温度8.4 ℃,肾器官表面平均温度8.3 ℃。
比较温控区间分别为(-0.5±1.5) ℃、(0.5±1.5) ℃和(-0.2±1.2) ℃的控制方案,温控区间为(0.5±1.5) ℃时降温时间最短,升温时间最长,且达到温度设计要求。
[关键词] 器官保存;蒸气压缩制冷;降温时间;温度控制 中图分类号:TB61+1; R318.52文献标识码:ADesign and Experimental Research of Organ Perfusion System Based on VaporCompression RefrigerationJIN Binhui 1, 2, DU Jie 1, LIU Baolin *1(1-Institute of Biothermal and Technology, University of Shanghai for Science and Technology, Shanghai, 200093, China; 2-School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China)[Abstract] Aiming at the problem that the internal temperature of organ cryopreservation equipment is easy to rise due to limited cold storage capacity during long-distance transportation, which affects the quality of organ preservation, an organ perfusion system is designed by using active refrigeration. The basic model of the equipment is established and the system is tested. The results showed that when the temperature control range was (2.5±2) ℃, the surface of renal organs decreased from 37 ℃ to 8 ℃ and remained basically constant after 5 hours. After the test to the 14th hour, the temperature of the cold storage box rises to about 4.5 ℃, the refrigeration system is started, the average cooling time is 0.46 h, and the average heating time is 1.3 h. The average temperature of organ storage room is 8.4 ℃, and the average temper ature of renal organ surface is 8.3 ℃. Comparing the control schemes with temperature control intervals of (-0.5±1.5) ℃, (0.5±1.5) ℃ and (-0.2±1.2) ℃, the temp erature control interval of (0.5±1.5) ℃ has the shortest cooling time and the longest heating time, and the temperature is always within the storage temperature range required by the kidney, meeting the design requirements.[Keywords] Organ preservation; Vapor compression refrigeration; Cooling time; Temperature control*刘宝林(1968—),男,教授,博士。
《中国科学: 物理学力学天文学》投稿须知《中国科学: 物理学力学天文学》(中文版, 英文名SCIENTIA SINICA Physica, Mechanica & Astronomica)和SCIENCE CHINA Physics, Mechanics & Astronomy(英文版)是中国科学院和国家自然科学基金委员会共同主办、《中国科学》杂志社出版的学术刊物. 力求及时报道物理学、力学和天文学基础研究与应用研究等方面具有创新性和高水平的最新研究成果, 月刊, 中英文版每月1日出版.《中国科学: 物理学力学天文学》与其英文版SCIENCE CHINA Physics, Mechanics & Astronomy是两个相对独立的刊物. 前者被《中国科学引文数据库》、《中国期刊全文数据库》、《中国科技论文与引文数据库》和《中国数字化期刊群》等收录; 后者被SCI, EI, Astrophysics Data System, Current Contents, Google Scholar, Index to Scientific Reviews, INSPEC, MathematicalReviews, MathSciNet等国际著名检索系统和数据库收录.1 用稿原则投给《中国科学: 物理学力学天文学》的文章必须未在其他任何地方、以任何形式发表过. 本刊不接受“一稿多投”之文章, 如发现此类投稿, 我们将通知作者单位和对方期刊.《中国科学: 物理学力学天文学》的原创性研究论文应同时具备以下条件:(ⅰ) 是物理学、力学、天文学和相关领域基础理论或应用研究的最新成果;(ⅱ) 具有重要科学意义, 有创新(新思路、新方法、新认识、新发现等);(ⅲ) 对本领域或(和)相关领域的研究有较大的促进作用.2 栏目设置《中国科学: 物理学力学天文学》设有以下3个栏目:评述: 综述所研究领域的代表性成果和研究进展, 评论研究现状, 提出今后研究方向的建议. 要求作者在该领域从事过系统的研究工作, 或者所做工作与该领域的研究紧密相关.论文: 报道物理学、力学和天文学各领域具有创新性、高水平和重要科学意义的最新科研成果.快报: 简明扼要地及时报道物理学、力学和天文学各领域具有创新性和新颖性的阶段性科研成果.3 写作要求文章应论点明确、数据可靠、逻辑严密、结构简明; 尽量避免使用多层标题; 文字、图表要简练, 用较少的篇幅提供较大的信息量; 论述应深入浅出、表达清楚流畅; 专业术语运用准确, 前后保持一致. 请参考新近出版的《中国科学: 物理学力学天文学》, 详细了解写作格式.题目:是文章的点睛之处, 要紧扣主题, 简明扼要, 但要有足够的信息, 能引起读者的兴趣, 也方便检索. 应避免使用大而空的题目, 最好不用“…的研究”、“…的意义”、“…的发现”、“…的特征”等词; 尽可能回避生僻字、符号、公式和缩略语. 一般不超过24个汉字, 英文不超过20个单词.作者和作者单位:在论文中署名的每一位作者都应该是对论文工作有实质贡献的人员, 应对文中的论点和数据负责. 署名单位必须是该项研究的实际完成单位. 单位名要写全称, 同时提供单位所在城市名和邮政编码. 如果作者分属不同单位, 使用上角数字标示作者所属单位序号, 并请提供通讯作者的E-mail.摘要:应反映论文的主要观点, 概括地阐明研究的目的、方法、结果和结论, 能够脱离全文阅读而不影响理解. 尽量避免使用过于专业化的词汇、特殊符号和公式. 摘要的写作要精心构思, 随意从文章中摘出几句或只是重复一遍结论的做法是不可取的, 以100~200字为宜. 摘要中不能出现参考文献序号.关键词:用于对研究内容的检索. 因此, 关键词应紧扣文章主题, 尽可能使用规范的主题词, 不应随意造词. 须列出反映文稿内容特征的中、英文对应的关键词、PACS(Physics and Astronomy Classification Scheme)专业代码3~8个, 按其重要性顺列、用空格隔开.基金资助:写在通讯作者E-mail 之后, 列出资助基金来源, 并注明项目批准号. 格式如“国家自然科学基金(批准号: ×××)和国家重点基础研究发展计划(编号: ×××)资助项目”. 基金名称要写全称.正文:应以描述文章重要性的简短引言开始. 专业术语应有定义, 符号、简略语或首字母缩略词在第一次出现时应写出全称, 缩略词用括号括起, 下面直接引用, 不再写全词.引言:应简要回顾本文所涉及到的科学问题的研究历史, 简要介绍相关理论或研究背景. 需要列举相关的参考文献, 尤其是近2~3年内的研究成果. 应非常明确地给出本研究的目的, 以及与以往研究的不同之处, 并在此基础上提出本文要解决的问题, 最后扼要交代本研究所采用的方法和技术手段等. 引言部分不加小标题, 不必介绍文章的结构.材料和方法:主要是说明研究所用的材料、方法和研究的基本过程, 应描述清楚, 引用相关文献, 使读者了解研究的可靠性,也使同行可以根据本文内容验证有关实验.讨论和结论:应该由观测和实验结果引申得出, 并注意与其他相关的研究结果进行比较, 切忌简单地再罗列一遍实验结果. 讨论得出的结论与观点应明确, 实事求是.图:应按正文中出现的先后顺序编号, 并按照“文先图后”的原则置于正文中的相应位置处. 黑白图和彩色图的分辨率不能低于600 dpi, 图中线条要清晰, 线条粗细约0.5~0.6 mm. 中文图中的汉字为7 pt的幼圆字体, 英文图中的文字和阿拉伯数字为7 pt的Arial Unicode MS字体. 图的宽度分两种: 半栏图宽6.5 cm, 通栏图宽不超过14 cm. 请尽量使用通栏图. 图的长度一般不超过18 cm.表:用三线表, 即表格采用横线表形式,纵向不画线. 横线数量不限, 需分开的内容尽量用横线分开. 请将表格插入到word文件中的相应位置.公式:以阿拉伯数字连续编号, 并用圆括号括起置于公式右侧.致谢:向评审人和对该文有帮助的人士表示谢意.参考文献:采用顺序编码制进行文内标注和文后著录, 即按正文中引用的先后顺序编号, 序号用方括号括起, 置于文中提及的文献著者、引文或叙述文字末尾的右上角. 参考文献引用是否得当是评价论文质量的重要标准之一. 如果未能在论文中引用与本项研究有关的主要文献, 尤其是近2~3年内的文献, 或是主要引用作者自己的文献, 编辑可能会认为对这篇文章感兴趣的读者不多. 对文中所引参考文献, 作者均应认真阅读过, 对文献的作者、题目、发表的刊物、年代、卷号和起止页码等, 均应核实无误, 切忌转引二手文献的不负责任的做法.4 参考文献著录体例参考文献著录规则请参考国家标准GB/T 7714-2005执行. 简要说明及示例如下:(ⅰ) 西文人名一律“姓”全拼在前, “名”缩写在后, 名缩写不加缩写点, 姓、名中间加空. “姓”首字母大写, 其余小写; “名”只写首字母, 大写, 两缩写名间加空. 外国人名中间有连字符的, 照加; 中国人名, 中间一般不加连字符.(ⅱ) 引用多位作者合著的文章时, 只列前3位作者, 后加“等(et al)”.(ⅲ) 西文文章题目中, 首词和专有名词的首字母大写, 其余一律小写.(ⅳ) 刊名按照ISO规范缩写, 不加缩写点. 如SCIENCE CHINA Physics, Mechanics & Astronomy应写为Sci China Phys Mech Astron.(ⅴ) 西文书名和论文集名中实词首字母一律大写, 介词和连词为小写, 但首词和4个字母以上的介词首字母应大写.(ⅵ) 非正式出版物不能作为参考文献, 只能作为脚注.(ⅶ) 互联网主页(网址)不作参考文献, 放在正文中.示例:期刊1 苏晓龙, 贾晓军, 谢常德, 等. 用正交压缩态光场产生连续变量类GHZ和类Cluster四组分纠缠态. 中国科学G辑: 物理学力学天文学, 2007, 37(6): 689—6992 Wang H P, Luo B C, Chang J, et al. Specific heat andrelated thermophysical properties of liquid Fe-Cu-Mo alloy. Sci China Ser G-Phys Mech Astron, 2007, 50(4): 397―4063 Qin Y H, Liu F, Yin H W, et al. Photonic structure in thewings of Papilio Bianor Ganesa. Chin Sci Bull, 2007, 52(23): 3183―31884 田赫, 掌蕴东, 王楠, 等. 环型谐振微环光波导链中光群速度的控制. 科学通报, 2006, 52(20): 2353―23565 Hu X, Ng S C, Li Y, et al. Cooling-rate dependence of thedensity of Pd40Ni10Cu30P20 bulk metallic glass. Phys Rev B, 2001, 64(17): 172201注意: 1) 引用增刊论文时, 卷号后注明“(增刊)或(Suppl)”.2) 已被接收但尚未正式发表的论文, 缺年、卷(期)、页码中任一项的, 只能放在脚注中, 注明“已接受(In press)”. 没有卷期号及起止页码, 但有doi号, 可以作为参考文献列出.专著1 惠希东, 陈国良. 块体非晶合金. 北京: 化学工业出版社,20062 Gaydon A G, Wolfhard H G . Flames. 2nd ed. London:Chapman and Hall Ltd, 1960. 30—35注意: 第一版不用列出.论文集1 Hayes D, Hixson R S, McQueen R G. High pressure elasticproperties, solid-liquid phase boundary and liquid equation of state from release wave measurements in shock-loaded Copper. In: Furnish M D, Chhabildas L C, Hixson R S, eds.Shock Compression of Condensed Matter-1999. New York: American Institute of Physics, 2000. 483-4882 王东晓. 南海环流多时空尺度与局地海气相互作用. 见: 苏纪兰, 主编. 南海环境与资源基础研究前瞻. 北京: 海洋出版社, 2001. 150—155注意: 第一版不用列出.会议论文集1Dmtriev V. Complete tables of the second rank constitutive tensors for linear homogeneous bianisotropic mediadescribed by point magnetic groups of symmetry and some general properties of the media. In: Proceedings of IEEE MTT-S IMOC’99. Be rlin: Springer, 2000. 435—4392 魏志义. 全固态啁啾镜补偿色散的自锁模Ti:Al2O3激光器.见: 第十四届全国激光学术报告会论文集. 北京: 激光与红外编辑部, 1999注意: 非正式出版的会议论文集只能作为脚注.学位论文1 李志辉. 从稀薄流到连续流的气体运动论统一数值算法研究.博士学位论文. 绵阳: 中国空气动力研究与发展中心研究生部, 2001. 1―102 Pegan S D. Molecular Gating Dynamics of the CytoplasmicDomains of Inwardly Rectifying Potassium (Kir) Channels.Doctor Dissertation. San Diego: University of California, 2006技术报告Chang V. The Past, Present and Future of the Linux Operating Systems. 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木星系统及能源利用介绍了木星的一些特征和木星的伽利略卫星。
对木星能源的利用提出了三个设想。
标签:木星;能源;氢1木星木星是太阳系由内向外的第五颗卫星,在中国基于五行,这颗行星被称为木星。
罗马人称其为朱庇特,是罗马神话中的神。
木星是太阳系中最大的行星,是个气体行星,有60多颗卫星,就像个小型的太阳系。
木星半径为69,911km左右。
在地球上肉眼也可以看到木星。
理论模型显示如果木星的质量比现在更大,它将会继续收缩[1]。
木星是太阳系内最频繁遭受到彗星撞击的行星[2]。
在1994年超过20颗苏梅克-列维九号彗星的碎片撞击在木星的南半球。
如果没有木星,这颗彗星可能会撞向地球,结果将是灾难性的。
木星最著名的特征是大红斑。
这个大红斑实际是个存在了很久的反气旋风暴,是逆时针旋转的,它的直径比地球直径还大。
2木星的伽利略卫星在1609年,伽利略发明了天文望远镜。
1610他用望远镜观察木星并记录了木星的四个卫星。
这四个卫星被称为伽利略卫星,即现在的木卫一至木卫四。
这四个卫星尤其是木卫二具有重要的探索价值。
木卫一直径为3642km,,比月球稍微大一点,是太阳系的第四大卫星。
木卫一有400多座活火山。
在1995年伽利略号飞掠过木卫一时,发现其具有巨大的铁核[3]。
木卫二是太阳系的第六大卫星,比月亮稍微小。
它的上面覆盖着冰,冰盖的厚度有人认为是几千米,也有人认为是数十千米[4]。
冰盖上有许多裂缝。
冰盖下可能有水,从而有生命。
木卫三作为太阳系最大的卫星,其大小比水星还要大。
木卫三拥有磁场。
其磁场可能是由富铁的流动内核的对流运动所产生的。
[5]木卫四是太阳系第三大卫星。
它是一颗同步自转卫星,即木卫四的自转周期等于其公转周期。
3 木星能源的利用3.1木星的元素分析木星有89%左右的氢和差不多10%的氦,还有微量的甲烷,乙烷和水蒸气等成分。
木星可能有岩石的核心和重元素[6]。
由木星的元素分析知,作为气体行星的木星,其氢的含量非常高。
Edge Go User Manual1. Safety NotesTo reduce the risk of electrical shocks, fire, and related hazards:Do not remove the screws, cover, or cabinet. There are no user-serviceable parts inside.Refer servicing to qualified service personnel.Do not expose this device to rain, moisture or spillover of liquid of any kind.Should any form of liquid or a foreign object enter the device, do not use it. Do not operate the device again until the foreign object is removed or the liquid has completely dried and its residues fully cleaned up. If in doubt, please consult the manufacturer.Do not handle cables with wet hands!Avoid using the device in a narrow and poorly ventilated place, which could affect its operation or the operation of other closely located components.If anything goes wrong, unplug the device first. Do not attempt to repair the device yourself. Consult authorized service personnel or your dealer.Do not install near any heat sources such as radiators, stoves, or other devices(including amplifiers) that produce heat.Do not use harsh chemicals to clean your unit. Clean only with specialized cleaners for electronics equipment.To completely turn off the device, unplug the cable.Both occasional and continued exposure to high sound pressure levels from headphones and speakers can cause permanent ear damage.The device is designed to operate in a temperate environment, with a correct operating temperature of 0-50 °C, 32-122 °F2. Quick StartCongratulations on purchasing your Antelope Audio Edge Go bus-powered modeling microphone! There are just a couple of steps to go through before you are ready to begin recording.1. Download and install the Edge Go USB Driver and Antelope Audio Launcher for your operating system.2. Place the Edge Go into the shockmount or desktop stand and connect the microphone to your computer using a standard USB C cable (one is provided in the box), or USB C to USB Type-A (male) cable.3. Start the Antelope Audio Launcher. Once it's running, update the device firmware and install the PC/Mac Control Panel for Edge Go. It all happens inside the Launcher.4. Head to the Software tab and install the EdgeDuo package to get the mic emulations and effects (FPGA) for Edge Go. Yes, they are the same as in our coveted Edge Duo large-diaphragm condenser modeling mic.5. Should you wish to use the mic emulations and effects as native plug-ins in your DAW, download and install the PACE iLok License Manager software. Plug in an iLok v2/v3 USB dongle (sold separately) and use the activation codes from the leaflet to download and authorize the plug-ins.Congratulations! You are now ready to turn Edge Go into the heart of your recording setup. Thank you for choosing Antelope Audio.Tip: Use Antelope Launcher for download and installation, iLok License Manager for authorization.Tip: Never used audio software (DAW) before? Plug in a pair of headphones into the 3.5mm jack and explore the presets inside the Control Panel as you talk or play into the microphone. Hear the difference made by the real-time mic emulations and effects. Experiment with stacking effects and adjusting parameters to taste. As long as it sounds good, you are doing it right!Experiencing any difficulties with the initial setup? Head to for a Live Chat session with a Customer Support specialist, or reach out over phone and e-mail. Availability times are as follows:•Support By PhoneUS time: 00:00 a.m. – 08:00 p.m. (CST), Monday – FridayEuropean time: 06:00 a.m. – 02:00 a.m. (GMT), Monday – Friday.US Phone Number (916) 238-1643 / UK Phone Number +44 1925933423•Live ChatUS time: 00:00 a.m. – 02:00 p.m. (CST), Monday – FridayEuropean time: 06:00 a.m. – 08:00 p.m. (GMT), Monday – Friday.If you’re trying to reach us outside working hours, we advise you to file a ticket in our customer support system or leave a voice message.3. The Control Panel and You1. Input Level KnobAdjusts mic gain.Tip: Don’t push the meters into the red. It means you are overdriving the Edge Go’s built-in preamp and clipping occurs, distorting your recording in an audible and unpleasant manner.Tip: For voice recordings, adjust mic gain according to the nominal (regular) level of your speaking or singing voice. If your performance is particularly dynamic (it has big changes in volume), calibrate to the loudest parts, making sure the meters don’t go into the red. This way, you are leaving enough headroom to capture the entirety of your performance without unwanted clipping.2. Input Level MetersA visual representation of your input signal level. As mentioned above, avoid pushing the meters into the red to avoid distortion.Tip: Edge Go is a dual-membrane microphone which records in Stereo by summing the input from both membranes. Hence the two L/R meters.3. Sample Rate SelectorAdjusts the sample rate, starting at 44.1kHz (CD Audio quality) and reaching up to 192kHz. The higher the sample rate, the higher the recording fidelity, at the cost of additional computer processing power.Tip: A good practice is to record at a higher sample rate and export at a lower sample rate. This method is called “downsampling” and results in higher fidelity than if you were to record at a lower sample rate.For a visual example of downsampling in action, watch a YouTube video recorded in 4K resolution and played back at 1080p resolution, then watch a video shot in regular 1080p. The difference in quality tends to be very noticeable, and it’s exactly the same with digital audio.Tip: Another good practice (though not mandatory) is to export at half the sample rate you recorded at. For example, record at 96kHz and export at 48kHz.4. Session RecallSave and load Sessions – think of them as convenient snapshots of the entire Control Panel, including presets, effect settings, gain adjustments, and all other parameters.5. Device SelectorLets you choose among multiple Edge Go microphones connected to your computer.6. Settings ButtonOpens the Settings Panel with the following parameters:1. Buffer size (samples)Adjust the buffer size. The lower it is, the lower latency you will experience at the cost of computer processing power.2. ASIO Control (Windows only)Opens the ASIO driver control panel for tweaking.3. USB Streaming modeChoose the one which suits your computer the best.Back to the Control Panel overview:7. About ButtonProvides device, firmware and software information.8. Minimize ButtonMinimizes the Edge Go Control Panel.9. Close ButtonCloses the Edge Go Control Panel.10. Headphone Output Level MetersA visual representation of your headphone output signal level. Avoid pushing the meters into the red to avoid unpleasant distortion and risking your hearing.11. Headphone Output Level KnobAdjusts headphone output level.Tip: Avoid exposing yourself to loud sounds, especially for long durations. You might damage your hearing.Tip: Take a 15-minute break from monitoring or mixing once every 45 minutes to keep your ears fresh.12. Mixer Hide/Show SwitchExtends the Edge Go Control Panel to include the following parameters:1. Reverb sendsAdjust the amount of reverb sent to each mix bus.2. USB ½ & USB ¾ OutputsControl the amount of system audio (web browser, YouTube, media apps, DAWs) sent to the Edge Go’s headphones output.3. Edge Go OutputAdjust the amount of processed audio from the Edge Go heard through its headphones output. Tip: Mute buttons are available for each mix bus.Tip: You cannot add effects processing to system audio, other than reverb.Tip: Configure your system audio outputs from Audio & MIDI Settings in macOS, or the Windows Control Panel. Edge Go has four outputs which can be assigned to the Left and Right channels in your operating system.14. Effects RackClick to launch the Effects Rack where you can stack audio effects and adjust their parameters to taste. It looks like this when empty:You are given the ability to save and load presets; bypass or delete all effects simultaneously; and stack effects from the categories inside the drop-down menu. All effects can be re-ordered in the virtual rack by dragging and dropping them in place.Tip: Unless you prefer the natural sound of the Edge Go’s built-in preamp, always start your effects chain with a preamp emulation.Tip: Add EQ before compression. This way, you will be compressing the equalized signal. This is not a hard and fast rule, but a reliable starting point.Tip: Manuals for the effects that come with the Edge Go are available in the Customer Support section on the Antelope Audio website.15. Preset SelectorUse presets designed by studio professionals as a starting point towards nailing the type of sound you are after.16. Mic Emulation & Polar Pattern SelectorChoose the active microphone emulation from the drop-down menu. Use the Edge Go model to disable mic modeling. Click the microphone visual to access the polar pattern selector. Use the knob to dial in your preferred polar pattern, which may be Omni, Cardioid, Figure-8 and anything in between.Tip: With Native plug-ins, it is possible to add mic emulations and effects to existing Edge Go recordings in a DAW. For optimum results, said recordings must be Stereo and “dry” - that is, recorded without mic emulations and effects. Simply load the plug-ins on the recorded track and go to town.You now know enough to master the Edge Go. With recording quality and production ease no longer an obstacle, you are free to unleash the slickest-sounding recordings upon the unsuspecting world.We wish you fun and productive times with this brilliant microphone.With compliments,Team Antelope。
ReviewPrinciple and applications of microbubble and nanobubble technology for water treatmentAshutosh Agarwal,Wun Jern Ng,Yu Liu ⇑Division of Environmental and Water Resource Engineering,School of Civil and Environmental Engineering,Nanyang Technological University,50Nanyang Avenue,Singapore 639798,Singaporea r t i c l e i n f o Article history:Received 15February 2011Received in revised form 24May 2011Accepted 25May 2011Keywords:Microbubbles Nanobubbles Free radicals Degradation Disinfection Defoulinga b s t r a c tIn recent years,microbubble and nanobubble technologies have drawn great attention due to their wide applications in many fields of science and technology,such as water treatment,biomedical engineering,and nanomaterials.In this paper,we discuss the physics,methods of generation of microbubbles (MBs)and nanobubbles (NBs),while production of free radicals from MBs and NBs are reviewed with the focuses on degradation of toxic compounds,water disinfection,and cleaning/defouling of solid surfaces including membrane.Due to their ability to produce free radicals,it can be expected that the future pros-pects of MBs and NBs will be immense and yet more to be explored.Ó2011Elsevier Ltd.All rights reserved.Contents 1.Microbubbles and nanobubbles.........................................................................................11752.Physics of micro and nanobubbles ......................................................................................11763.Generation of free radicals by collapsing microbubbles in water..............................................................11764.Methods for the generation of MBs and NBs ..............................................................................11775.Determination of bubble size ..........................................................................................11786.Water treatment by MBs and NBs technology.............................................................................11786.1.Degradation of organic pollutants .................................................................................11786.2.Water disinfection..............................................................................................11786.3.Cleaning and defouling of solid surfaces ............................................................................11797.Long-term perspectives of micro and nanobubbles technology ...............................................................1179References .........................................................................................................11791.Microbubbles and nanobubblesMicrobubbles (MBs)and nanobubbles (NBs)are tiny bubbles with a respective diameter of 10–50l m and <200nm,and have been explored for various applications.The existence of NBs as sta-ble entity has been debated for a long while due to some thermo-dynamic considerations.For example,the total free energy of the system has been supposed to increase along with the formation of NBs unless the surface was extremely rough.However,high Laplace pressure inside NBs would likely cause them to dissolve into solution quickly (Ljunggren and Eriksson,1997;Eriksson and Ljunggren,1999).Fig.1shows the key differences among macrobubbles,MBs and NBs.MBs tend to gradually decrease in size and subsequently collapse due to long stagnation and dissolution of interior gases into the surrounding water,whereas NBs remains as such for months and do not burst out at once (Takahashi,2009).It has been revealed that the interface of NBs consists of hard hydrogen bonds similar to those found in ice and gas hydrates.This in turn leads to reduced diffusivity of NBs that helps to maintain adequate kinetic balance of NBs against high internal pressure.0045-6535/$-see front matter Ó2011Elsevier Ltd.All rights reserved.doi:10.1016/j.chemosphere.2011.05.054Corresponding author.Tel.:+6567905254;fax:+6567910676.E-mail address:cyliu@.sg (Y.Liu).2.Physics of micro and nanobubblesThe existence of NBs at the liquid–solid interface has been dem-onstrated by various techniques, e.g.atomic force microscopy (AFM)(Tyrrell and Attard,2001;Holmberg et al.,2003;Steitz et al.,2003;Simonsen et al.,2004;Switkes and Ruberti,2004;Agrawal et al.,2005;Zhang et al.,2006a,b,c ).It has been shown that NBs at the liquid–solid interface resemble spherical caps with height and diameter of about 10and 100nm,respectively.In fact,this is supported by the fact that NBs can be fused by the tip of AFM to form a larger bubble (Simonsen et al.,2004).It was initially believed that NBs might have high surface tension,thus the gas should be ‘pressed out’of NBs within microseconds after their formation (Matsumoto and Tanaka,2008).However,NBs can form freely and remain stable for long periods of time under the right conditions.The stability of NBs results from a lower interfacial cur-vature than expected due to a high contact angle (Yang et al.,2003;Zhang et al.,2006c ).The formation of NBs in aqueous solutions of small organic molecules (e.g.tetrahydrofuran,ethanol,urea,and a -cyclodextrin)has also been reported (Jin et al.,2007a,b ).under a wide range of pH.Although OH Àand H +ions have been shown to influence the charging mechanism of the gas–water interface (Takahashi,2005).The f potential of the MBs has been found to be constant under similar water conditions irrespective of their size,indicating that the amount of electrical charge per unit area at the gas–water interface would remain constant (Takahashi,2005).Nevertheless,increased f potential with the rate of shrinkage of MBs has been observed during collapse of MBs (Fig.2).Decrease in size of MBs below the water surface results in high internal pressure inside MBs,which is directly proportional to the bubble’s diameter.The relationship between pressure and diame-ter is expressed by the Young–Laplace equation:P ¼PI þ4r d bð1Þwhere P is the gas pressure,PI is the liquid pressure,r is the surface tension of the liquid and d b is the bubble diameter.According to Henry’s law,the amount of dissolved gas surrounding a shrinking bubble increases with the increase in gas pressure.The area sur-rounding a MB has been shown to change its state in a pressure–temperature (P –T )diagram to favor hydrate nucleation (Sloan,1998).This is one of the typical characteristic of MBs.3.Generation of free radicals by collapsing microbubbles in waterAccording to the Young–Laplace equation (Eq.(1)),for a bubble with diameter 1l m at 298K,the internal pressure is about 390kPa,which is almost four times higher than the atmospheric pressure.Since the rate of increase in the internal pressure of MBs is inversely proportional to its size,a high pressure spot is eventually created at the final stage of the MB collapse (Fig.3).If the collapsing speed of MBs is higher than the speed of sound in water,the temperature inside the collapsing bubbles may increase drastically due to adiabatic compression.Since the shrinkage rate of the collapsing bubbles is extremely slow compared to the ultra-sonically induced cavitation bubbles,the temperature inside the Fig.2.Changes in the size and f potential of microbubbles over time (Takahashi et al.,2007b ).84(2011)1175–1180result,the decomposition of ozone for producingÅOH radicals would be expedited in case of ozone MBs(Takahashi et al., 2007a).The MBs of gases with oxidizing power(e.g.ozone)can be applied to various water treatment processes since the ozone MBs have high solubility and improved disinfection ability due to the generation ofÅOH radical and/or pressure waves(Sumikura et al.,2007).Generation of free radicals through the collapse of MBs in the absence of dynamic stimulus has been experimentally demon-strated by electron spin resonance spectroscopy(Takahashi et al., 2007b).5,5-dimethy-1-pyroroline-N-oxide was chosen as the spin-trap agent to trap the free radicals generated in the process of collapse.The solution pH was found to have significant effect on the quantity of free radicals generated by the collapse of oxygen MBs,e.g.lowered pH enhanced generation of free radicals.Mean-while,the type of gas used for the generation of MBs can also affect the quantity of free radicals generated.For example,oxygen MBsÅpassage of ultrasonic waves is so-called acoustic cavitation,while cavitation due to the pressure variations in theflowing liquid is termed as hydrodynamic cavitation.Acoustic and hydrodynamic cavitations may result in the desired physical and chemical changes in a solution,but optic and particle cavitations are incapa-ble of bringing about any change in the bulk solution.Millions of hot spots in the reactor can be generated through hydrodynamic and acoustic cavitation due to very high localized energy density which in turn results in extremely high pressure and temperatures in the range of10–500MPa and1000–10,000K,respectively(Suslick,1990).However,it should be noted that the collapse of MBs in the absence of dynamic stimulus would not favor the creation of such hot spots(Takahashi et al.,2007b). Nowadays,few methods have been developed for the generation of MBS and NBs.The two widely used methods are based on decompression and gas–water circulation.For the decompression type generator,a supersaturated condition for gas dissolution is created at high pressure of304–405kPa(Fig.4).At such high pres-sure,supersaturated gas is highly unstable and eventually escapes out from the water.As the result,large number of MBs would be generated instantly.However,for gas–water circulation type gen-erator,the gas is introduced into the water vortex,and gas bubbles are subsequently broken down into MBs by breaking up the vortex (Takahashi,2009).Generation of the ozone MBs through decompression has been found to be more efficient than through gas–water circulation(Ikeura et al.,2011).Similar to the decom-pression type,the venturi-type MB generator has also been widely used.This has the advantages of compact size,low pump power and high-density generation of MBs normally with a mean diame-ter below100l m.The venturi-type generator consists of three main parts,i.e.inflow,tubule and tapered outflow.Cavitation occurs due to decrease in static pressure of the pressurizedfluid entering the tubule part.In the tubule part,velocity of thefluid in-creases at the cost of decrease in static pressure.Simultaneously, gas entering into the tubule part from outside develops a multi-phase-flow of the gas and liquid.When thefluid exceeds the speed of sound,a pressure wall with a shock wave is created in the tubule.MBs are thus generated through the collision of gas with the pressure wall developed with a shock wave(Yoshida et al.,Fig.4.Decompression and gas–water circulation methods for the generation of MBs/NBs(Ikeura et al.,2011).84(2011)1175–11801177that generation of monodispersed MBs and NBs using the above methods still remain a major challenge.5.Determination of bubble sizeLaser diffraction particle size analyser has often been used to measure the size and size distribution of MBs and NBs(Kukizaki and Goto,2006;Tasaki et al.,2009b).The monodispersity of bub-bles is determined according to the particle size dispersal coeffi-cient d:d¼D90bÀD10bD50bð2Þwhere D90b ,D50band D10bare the diameters corresponding to90%,50%,and10%by volume respectively,on the relative cumulative bubble size distribution curve;D50brepresents the mean bubble diameter. The specific interfacial area(a,m2mÀ3)of MBs and NBs is defined by:a¼6e GD50bð3Þe G¼V GL Gð4Þwhere e G is the gas holdup,V G is the volume occupied by the gas phase(bubbles),V L is the volume occupied by the liquid phase. The particle size can also be determined by scanning electron microscopy(SEM).For this purpose,a replicafilm had been devel-oped(Ohgaki et al.,2010).Particle counting spectrometer for liq-uids which uses light-obscuration method can also be used for measuring the size distribution of MBs(Takahashi et al.,2003, 2007a).6.Water treatment by MBs and NBs technologyIn the past few years,more and more attention has been given to the potential applications of the MBs and NBs for water treat-ment due to their ability to generate highly reactive free radicals. Recently,MBs/NBs have been used for detoxification of water (Yamasaki et al.,2010),while it has been reported that air and nitrogen MBs/NBs can enhance the activity of aerobic and anaero-bic microorganisms in submerged membrane bioreactor.Evidence shows that nitrogen MBs/NBs cannot only be applied for water and wastewater treatment,but also for fermentation,brewing as well for human waste treatment.MBs/NBs have been found to catalyze chemical reactions,and enhance the detoxification efficiency, thereby improving the efficiency of chemical treatment of water. The main purpose of water pretreatment is to reduce biological, chemical and physical loads in order to reduce the running costs and increase the treated water quality.In this context,air MBs/ NBs as a pretreatment means has been shown to be highly benefi-cial for downsizing the water/wastewater treatment plants and improving the quality of product water(Yamasaki et al.,2009, 2010).6.1.Degradation of organic pollutantsMBs generated through hydrodynamic cavitation have been employed for degradation of various organic compounds,such as alachlor(Wang and Zhang,2009),p-nitrophenol(Kalumuck and Chahine,2000),rhodamine B(Wang et al.,2008)and decoloriza-tion of dye effluent stream(Sivakumar and Pandit,2002). Takahashi et al.(2007b)investigated the decomposition of phenol in aqueous solution with air MBs in the absence of dynamic stim-ulus(e.g.UV irradiation and incident ultrasonic wave).When 1.5mM phenol solution was subjected to air MBs collapse for3h without addition of acid,no change in the phenol concentration was observed.However,30%of phenol was decomposed after acid (e.g.nitric,sulfuric or hydrochloric acid)was added to the phenol solution,while intermediates,such as hydroquinone,benzoqui-none,formic acid and oxalic acid were detected.Phenol could therefore be removed by free radicals generated through collapse of air MBs in the presence of a strong acid.The removal of polyvi-nyl alcohol(an ozone resistant)in terms of TOC by collapse of ozone MBs was also achieved under strong acidic conditions in the absence of dynamic stimulus(Takahashi et al.,2007a).As dis-cussed earlier,the formation of hot spots by adiabatic compression of cavitation bubbles in an aggressive collapse process may further enhance organic degradation(Hart and Henglein,1986).However, no reduction in TOC concentration confirmed that the hot spots generated by the ultrasound did not boost the generation ofÅOH radicals for the TOC removal.Excessive accumulation of ions around the gas–water interface of the collapsing MBs would lead to ion concentrations high enough for converting ozone toÅOH rad-icals.The TOC reduction by ozone MBs under strong acidic condi-tions was much greater than using other conventional techniques.Ozonation of a mixture of benzene,toluene,ethylben-zene and xylenes had been reported at different salt concentrations ranging from0to2M(Walker et al.,2001).It was found that the production of MBs helped to improve the mass transfer efficiency and further enhanced the removal of soluble organics from simu-lated seawater.Ozonation of synthetic wastewater containing azo dye and CI Reactive Black5was investigated using collapsing ozone MBs (Chu et al.,2007).In this experiment,the total mass transfer coeffi-cient and pseudo-first order rate constant were found to be1.8and 3.2–3.6times higher than those found in the bubble contractor, respectively.It was clearly shown that the production ofÅOH radicals was increased in the MB system.Evidence shows that the production ofÅOH radicals using vacuum UV irradiations(Oppenländer and Gli-ese,2000)can lead to fast oxidation of organic compounds in water and wastewater as compared to the conventional ozone system withoutÅOH radicals(Echigo et al.,1996).In addition,use of vacuum UV is restricted because of the recombination of carbon-centered radicals during photo degradation which yields undesirable byprod-ucts,such as oligomers and polymers(Han et al.,2004).Recently,use of MBs and NBs technique to overcome the shortcomings of vacuum UV process has been explored(Tasaki et al.,2009a).Under vacuum UV irradiations the degradation of methyl orange in the presence of oxygen MBs was found to be accelerated due to the enhanced mass transfer of oxygen and substrate within the vacuum UV reactor (Tasaki et al.,2009b).The decolorization of methyl orange became faster under185+254nm irradiation with oxygen MBs.The critical role of NBs in degradation of surfactants and nonsurfactant under vacuum UV irradiations has also been investigated.The rate of min-eralization of sodium dodecylbenzenesulfonate with720nm NBs was found to be much faster than that with MBs(Tasaki et al., 2009a).The observed enhanced mineralization of surfactants can be attributed to the high adsorption capacity of NBs due to their small size,and large specific surface area that facilitates the reaction.6.2.Water disinfectionGeneration of highly reactive free radicals and turbulence asso-ciated with the collapsing MBs provides great potential for water disinfection.Hydrodynamic cavitation has been shown to be a much cost-effective technique for water disinfection as compared to acoustic cavitation.However,lab-scale study suggests that the cost of hydrodynamic cavitation for water disinfection is still high-er than conventional chlorination and ozonation(Jyoti and Pandit, 2001).1178 A.Agarwal et al./Chemosphere84(2011)1175–1180The effect of ozone MBs on Escherichia coli was investigated un-der various conditions.It has been found that the faster disinfec-tion kinetics of E.coli by ozone MBs was observed,leading to a reduced reactor size and small ozone dose as compared to the con-ventional ozone disinfection for the same disinfection efficiency of a2-log inactivation(Sumikura et al.,2007).In this process theÅOH radical and shock waves generated by the collapse of MBs have been considered as the main cause for inactivation of coliform, while specific contribution of each effect to inactivation of coliform still remains unknown.Moreover,high deactivation efficiency of E.coli has also been achieved in water disinfection by MBs gener-ated through hydrodynamic cavitation(Jyoti and Pandit,2001, 2003,2004;Arrojo et al.,2008;Mezule et al.,2009).Bathing pool assembly having water full of ozone NBs for rehabilitation has also been developed to prevent pathogen growth(Chen,2009).This assembly consists of a bath,a reservoir and two circulating sys-tems.The circulating systems are connected to bath and reservoir via oxygen and ozone generator.Each circulating system is equipped with high pressure emulsifying device that facilities gen-eration of free radicals and anions from dissolved oxygen and ozone.The amount of ozone in the bath and the reservoir is main-tained at the range of0.5–5and0.2–0.5mg LÀ1,respectively.At a pressure of304–1013kPa provided by the high pressure emulsify-ing device,ozone is rapidly dissolved into water and ozone NBs in the range of10–20nm are thus produced.It was found that the subsequent burst of NBs would provide a more effective means for cleaning and disinfecting both the bath and the reservoir than traditional ultrasonic vibrator.6.3.Cleaning and defouling of solid surfacesNBs have been applied for the prevention and removal of pro-teins adsorbed onto solid surfaces.It has been shown that adsorp-tion of proteins onto various surfaces could be inhibited by NBs, thus preventing the surfaces from fouling(Wu et al.,2006,2007). For example,NBs can block adsorption of bovine serum albumin on mica surface(Wu et al.,2006),while NBs also helps remove or-ganic contaminants from pyrolytic graphite(Wu et al.,2007,2008) and gold surfaces(Liu et al.,2008).Recently,similar defouling effect of NBs was also observed on stainless steel surface(Chen,2009).The use of high frequency,low power ultrasound along with MBs has shown great potential in control of bacteria and algae attachment onto solid surfaces(Broekman et al.,2010).Destabi-lized and reduced biofilms have been observed after treatment by MBs.The bubble size has been found to affect the membrane fouling in case of tubular(Cui et al.,2003)and hollowfiber mem-branes(Lu et al.,2008;Willems et al.,2009).(Tian et al.,2010) investigated the influence of mm sized air bubbles on membrane fouling of immersed hollowfiber membranes for ultrafiltration of river water,and found that continuous air bubbling would be more effective than intermittent bubbling in fouling control.In case of continuous bubbling,air bubbles scrub the membrane surface dur-ing the process offiltration and hence reduce the chances for the formation of concentration polarization and fouling layer on mem-brane surface.Moreover,it was observed that smaller air bubbles were more efficient in reducing fouling.In addition,similar phe-nomenon was also observed in other study of membrane fouling control by bubbling(Yeo et al.,2006;Van Kaam et al.,2008;Zarra-goitia-González et al.,2008;Cornelissen et al.,2009).7.Long-term perspectives of micro and nanobubbles technologyMBs and NBs have exhibited great potential in various engi-neering applications.For example,wide use of oxygen NBs has been anticipated due to their extremely high bioactivity and mass transfer efficiency.Due to their ability to generate free radicals without the use of any toxic chemical,MBs have been proven to be a new environmental friendly technique for oxidation of organic compounds,water disinfection and fouling control.It is reasonable to consider that MBs and NBs would have wide applications where materials come into contact with biological media,such as medical equipment,membrane cleaning,ship andfilter regeneration.MBs and NBs may provide a promising path for a convenient,clean, cheap and environmental friendly technique suitable for cleaning of conducting surfaces.Hence,it can be concluded that the use of MBs and NBs in developing new technology is still ahead to be explored.ReferencesAgrawal,A.,Park,J.,Ryu,D.Y.,Hammond,P.T.,Russell,T.P.,McKinley,G.H.,2005.Controlling the location and spatial extent of nanobubbles using hydrophobically nanopatterned surfaces.Nano Lett.5,1751–1756.Arrojo,S.,Benito,Y.,Martínez Tarifa,A.,2008.A parametrical study of disinfection with hydrodynamic cavitation.Ultrason.Sonochem.15,903–908. 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Shock compression of liquid deuterium up to109GPaG.V.Boriskov,A.I.Bykov,R.I.Il’kaev,V.D.Selemir,G.V.Simakov,R.F.Trunin,V.D.Urlin,and A.N.ShuikinRussian Federal Nuclear Center,All-Russia Research Institute of Experimental Physics,Sarov,Nizhni Novgorod Region607190,RussiaW.J.Nellis*University of California,Lawrence Livermore National Laboratory,Livermore,California94550,USA͑Received13May2004;revised manuscript received15October2004;published23March2005͒Hugoniot points of liquid D2were measured at shock pressures of107,54,and28GPa using convergingexplosively driven systems͑CSs͒.The two data sets measured with a laser͑L͒and pulsed currents͑PCs͒differsubstantially.Our results are in excellent agreement with the PC data and the error bars of the CS-PC data areless than half those of the L data.The limiting compression obtained from the bestfit to the CS-PC data is4.30±0.10at100GPa.The CS-PC data are in good agreement with path integral Monte Carlo and densityfunctional theory calculations,which is expected to be the case at even higher shock temperatures and pres-sures,as well.DOI:10.1103/PhysRevB.71.092104PACS number͑s͒:62.50.ϩp,47.40.NmThe single-shock compression curve͑Hugoniot͒of deute-rium up to100GPa͑1Mbar͒pressures has been controver-sial because limiting shock compression close to sixfold of initial liquid density has been reported using a high-intensity laser͑L͒͑Ref.1͒and limiting compression close to fourfold has been reported using large pulsed currents͑PCs͒.2–4That is,as pressure achieved with a single shock increases,so too does temperature,which limits compression at sufficiently high pressures.Examination of the systematics of single-shock compression of diatomic liquids suggests that the PC data are correct.5Deuterium in all the shock experiments is in thermal equilibrium because there are more than104col-lisions between atoms and/or molecules within the respective time resolutions.Deuterons in these experiments are classical.6Thus,there is no a priori reason whyfluid deu-terium would be expected to behave differently than other low-Z diatomics,as reported in Ref.1.In order to determine the correct Hugoniot of D2,we began experiments on solid7,8 and liquid samples in1999.In this paper we report Hugoniot points at109,54,and28GPa for liquid D2samples.Strong shock waves were generated with hemispherical convergence driven by explosives͑CS͒,the same method we used previously to measure points at121and61GPa for solid samples.7,8Our points at109and121GPa achieve lim-iting compression.Our points at109and121GPa and at54 and61GPa used liquid and solid D2samples,respectively, to demonstrate self-consistency and reproducibility.Our point at28GPa demonstrates agreement with data measured at lower pressures with a two-stage gas gun͑GG͒.9 To minimize uncertainties,our CS method10,11requires that a given experiment be repeated several times and the results averaged.We have performed thirteen cryogenic,ex-plosively driven experiments to obtain the three data points for liquid samples reported here.Our method produces data at100GPa pressures in the simple materials Al and Cu which are in excellent agreement with data obtained with a two-stage gun and planar explosives.12,13Thus,while our method produces relatively few data points,our results are in excellent agreement with data obtained by other techniques of demonstrated accuracy at shock pressures which can be obtained with all three methods.High shock pressures were generated by impact of a con-verging hemispherical steel shell accelerated to velocities as large as14km/s͑Ref.14͒onto an Al sample holder contain-ing liquid D2near20K.The data were analyzed with the shock-impedance match method.11Shock velocities were de-termined from shock transit times over measured distances. Measured shock transit times in both the Al sample holder and liquid D2were corrected for spherical convergence. Shock transit times in liquid D2were corrected for transit times through thin Al covers on detectors.We used an Al Hugoniot in excellent agreement with recent measurements to500GPa.15Our calculated Al release isentropes used to match shock impedances agree with measured Al release isentropes at conditions in liquid D2.2,16Initial Al density was corrected for its20K initial temperature.The points reported here͑CS͒and achieved in the previous L,PC,and GG experiments were performed in u s-u p space,where u s is shock velocity and u p is mass velocity.The Hugoniot equations17were used to calculate P andfrom u s and u p,where P is shock pressure andis shock-compressed den-sity.The shock states achieved in deuterium are listed in Table I.The error analysis is described in Ref.18.Mass velocity u p of deuterium is determined in P-u p space by matching shock impedance of an Al shock release isentrope with the shock impedance of deuterium on its Hugoniot͑0u s͒=P/u p,where0is initial density of liquid D2at20K.Weused Al release isentropes which are in good agreement with measured Al states releasing into aerogel with essentially the same density and shock impedance as liquid D2.2,16In the case of these deuterium experiments,uncertainties in mea-sured u s are the dominant source of error in determining u p. Systematic errors in u p are negligible because our Al release isentropes agree with experiment.This is in contrast to pre-vious experiments9in which systematic uncertainties in u p were taken into account because at that time Al release isen-PHYSICAL REVIEW B71,092104͑2005͒tropes could only be calculated.18The error analysis de-scribed above gives error bars of the u s-u p points,which were then used to calculate the corresponding error bars for the pressures and densities in Table I.Since our goal is to minimize uncertainties,we now make use of the fact that there are19CS and PC u s-u p points in excellent agreement at pressures near100GPa and these points have a linear u s-u p relation.In this situation,the un-certainty in calculating a value of u s from the linearfit is substantially lower than the uncertainty in any one experi-mental point.Thus,we now determine least-squaresfits to the u s-u p data and use thesefits and the uncertainties in them, caused by uncertainties in the experimental data,to calculate P,compression/0,and the uncertainty in/0.It is straightforward to least-squaresfit the data because u s-u p relations of low-Z diatomic molecules are linear or nearly so with small͑ϳ3%͒deviations caused by molecular dissociation.5Since two points were measured with solid samples,7,8shock velocities of these two points were cor-rected downward by1.5%to account for their higher initial density relative to that of the liquid samples.Weighting fac-tors equal to the reciprocal of the uncertainty in each mea-sured u s were used in thefitting procedures.The CS,PC,L, and GG u s-u p data are plotted in Fig.1along with thefits.The CS,PC,and GG data were analyzed in regions1–3, the dark curves in Fig. 1.In thefirst region,3Ͻu p Ͻ9km/s,thefit to the GG data is linear͑u s1=C1+S1u p͒with slope S1=1.21±0.04.9In the third region,15Ͻu pϽ22 km/s,thefit to the combined CS-PC data is linear͑u s3=C3 +S3u p͒with C3=1.704±1.5km/s and S3=1.22±0.08.The standard deviations in C and S areC=͓͚j͑␦C j͒2͔1/2and S=͓͚j͑␦S j͒2͔1/2,where␦C j=C j−C,␦S j=S j−S,C and S are obtained from the bestfit and C j and S j are the values of C and S obtained by varying the j th value of u s3by its experi-mental uncertainty.Standard deviations in C and S are rela-tively large because all terms in these sums are positive.For our purpose,however,uncertainties in C an S are not important.Rather,it is the uncertainty in the Hugoniot of deuterium calculated from thefit that is important.The un-certainty in u s calculated from thefit at a given u p varies with u p because data points at the extremes of u p have the largest effect on thefit and these points also have larger error bars.The standard deviation in u s3as a function u p is given by ͓u s͑u p͔͒=͓͚j͑␦C j+u p␦S j͒2͔1/2.19This technique was also used to analyze Hugoniot data of Al,Cu,and Ta.12Uncer-tainties in shock velocity calculated with thefit at a given u p are relatively small because␦C j and␦S j have opposite signs. For19CS and PC points in the range15Ͻu pϽ22km/s,͓u s͑u p͔͒=͑3.216–0.3301u p+0.008487u p2͒1/2.͓u s͑u p͔͒/u s has a minimum of0.4%at u p=19.5km/s and85GPa, which is precisely the regime in which high accuracies are needed.Experimental uncertainties in our shock velocity measurements atϳ100GPa are1.4%.In the second region,9Ͻu pϽ15km/s,the combined CS-PC data have a small curvature.The shock pressures cor-responding to these velocities are20and50GPa,respec-tively.This is the same shock pressure range in which optical reflectivity experiments indicate that deuterium undergoes a transition from a diatomic insulator below20GPa to a mon-atomic,strong-scattering metal above50GPa.20This reflec-tivity data justifies treating the small curvature in this region as physical in nature.Thus,in the region9Ͻu pϽ17km/s a cubic polynomial was used tofit15CS and PC points:u s2 =A1+A2u p+A3u p2+A4u p3,where A1,A2,A3,and A4are con-stants,the simplest form to represent the universal behavior of low-Z diatomics.5This expression represents an initial softening in u s2caused by dissociation,followed at higher u p by a stiffening in u s2caused by completion of the temper-ature-driven nonmetal-metal transition from Maxwell-Boltz-mann statistics for the diatomic insulator to Fermi-Dirac sta-TABLE I.Shock-compressed states of deuterium,where0is initial density,u p is particle velocity,u s is shock velocity,P is pressure,andis density.The lower initial densities are for liquid samples;the higher initial densities are for solid samples͑Refs.7 and8͒.To obtain thesefive data points,twenty three cryogenic explosively driven experiments were performed and the results averaged.0͑g/cm3͒u p͑km/s͒u s͑km/s͒P͑GPa͒a͑g/cm3͒Ref.0.17110.95±0.2015.23±0.328.5±0.80.608±0.050.17115.38±0.420.38±0.353.6±0.60.697±0.060.19915.06±0.1520.51±0.261.4±0.80.749±0.0470.17122.05±0.328.87±0.4108.8±30.724±0.070.19921.59±0.428.64±0.4123.0±20.808±0.088100GPa=1Mbar.FIG.1.Shock velocity u s versus mass velocity u p for deuterium:open diamonds͑this work͒,open triangles͑Refs.7and8͒,solidsquares͑Refs.2–4͒,solid circles͑Ref.9͒,open squares͑Ref.1͒.Solid curve is least-squaresfits in regions1–3;dashed curve inregion4is linearfit to Ref.1.tistics for the monatomic metal.21This cubic fit is the solid curve in the range 9Ͻu p Ͻ15km/s,region 2in Fig.1.The laser data ͑L ͒are linear ͑u sL =C L +S L u p ͒in the range 18Ͻu p Ͻ32km/s,1the dashed line in region 4of Fig.1.Our experimental results ͑CS ͒are in excellent agreement with the PC data and the error bars of the CS and PC data sets are less than half those of the L data.Figure 1shows that the CS-PC and the L data agree at the extremes of the error bars of each individual data point in u s -u p space.Thus,on the basis of the error bars of the individual data points all the data sets agree.However,the significantly smaller error bars of the fits caused by all the error bars of all the individual points show that the CS-PC data should be used for comparison of ex-periment with theory.The u s -u p fits to the CS-PC,L ,and GG data were trans-formed to P versus compression ͑/0͒.The results are shown in Fig.2as the solid ͑segments 1–3͒and dashed ͑4͒curves,respectively.Thus,relatively small differences in u s -u p space ͑solid and dashed curves in Fig.1͒cause sub-stantial differences in P -compression.The error bars of com-pression for the solid and dashed curves in the range 50to 110GP are their standard deviations calculated from the uncertainties in the u s -u p fits,which are caused by uncertain-ties in all the measured shock velocities.No effort was made to obtain a smooth join in P −͑/0͒space between regions 2and 3,which occurs within the error bars of the two fits.The fits to the experimental data are now compared to theories in the two extreme limits,the cases in which all interactions are taken into account ͑PIMC and DFT compu-tations ͒and the case in which all interactions are neglected ͑free electrons ͒.The Hugoniot calculated with the path inte-gral Monte Carlo ͑PIMC ͒method,22which uses no adjust-able parameters,is the dotted curve in Fig.2.The PIMCresults are essentially coincident with the fit to the CS-PC data.PIMC assumes that interactions between charged par-ticles are Coulombic ͑1/r ͒,that all particles are in thermo-dynamic equilibrium,and that nodal surfaces may be used to solve the fermion sign problem.This method is valid above 5000K,where shock-compressed deuterium is assumed to be monatomic.Density functional theory ͑DFT ͒has a spatial criterion for the existence of molecules,namely,two atoms form a mol-ecule when they are mutually nearest neighbors or nearest neighbors for a minimum of two or more vibron periods.In calculations between shock pressures of 20and 100GPa,ϳ80and ϳ100%of D 2molecules dissociate into atoms at 50and 100GPa,respectively,23which is consistent with experiment.20These calculations,the open circles in Fig.2,are in excellent agreement with Refs.2–4.Both PIMC and DFT are in excellent agreement with ex-periment and say that deuterium is monatomic or nearly so above 50GPa on the Hugoniot.Other calculations 24–27ap-proach limiting compressions of essentially 4.3-fold,as well.28Thus,limiting compressions of the fit to the CS-PC data and of several calculations are essentially the same and are relatively close to the limiting shock compression of 4.0of an initially degenerate free-electron gas.21Slopes of u s -u p fits to experimental data are now com-pared to PIMC and DFT calculations and to results for free electrons and ideal gases of D and D parison of these slopes,is more stringent than comparisons of the data itself.Also,this comparison gives an estimate of the effect of tem-perature.Slopes du s /du p derived from the fits to the GG-CS-PC data in Fig.1and their error bars are plotted in Fig.3.These slopes are constants in the first and third regions.In thesec-FIG.3.du s /du p versus u p .Solid curve:1is from Ref.9;2is derivative of solid curve in Fig.1for 9Ͻu p Ͻ17km/s;3is linear slope of solid line above u p =15km/s in Fig.1.Dissociation occurs between u p =ϳ9and ϳ15km/s,which corresponds to 20and 50GPa ͑Ref.20͒.Dashed line is slope of dashed line in region 4of Fig.1.Error bars are standard deviations of slopes S of linear fits caused by uncertainties in shock velocity measurements.Dot-dash lines are slopes corresponding to limiting compressions of mon-atomic and diatomic ideal gases and free-electron gas,asindicated.FIG.2.Pressure ͑P ͒versus compression ͑/0͒calculated with Hugoniot equations and u s -u p fits in Fig.1.Solid and dashed curves correspond to solid and dashed curves in Fig.1.Error bars are standard deviations of fits calculated from uncertainties in measured shock velocities.Dotted curve and temperatures were calculated with PIMC ͑Ref.22͒.Open circles calculated with DFT ͑Ref.23͒.ond region,du s/du p is the derivative of the cubicfit to thedata in this range.Between9and17km/s the slope of thefitto the CS-PC data has an initial sharp minimum,ϳ25%lessthan that of the molecular phase,followed by a broadermaximum.The open circles are obtained from DFT calcula-tions.The slope of the PIMC results͑dots͒was calculated bytransforming published P-results to u s-u p.Values of du s/du p obtained fromfits to the experimental data are ingood agreement with PIMC and DFT results.For compari-son,limiting slope S lim͑CӶSu p͒is1.33for both a free elec-tron gas and an ideal monatomic gas of deuterons;limitingslope of a diatomic ideal gas is1.17.The latter three are thedot-dash lines,as indicated.Also plotted in Fig.3is the slope of the u s-u p data of Ref.1,S L=1.10±0.17for18Ͻu pϽ32km/s͑long dashes͒.The relatively low value of this slope for u pϾ18km/s is incon-sistent with dissociation proposed in Ref.1,which is ob-served experimentally to be essentially complete by u p =15km/s.20Mass velocity of the L data was obtained by an absolute determination of u p by transverse radiography.In contrast,the CS,PC,and GG data obtained u p with the shock-impedance match method with Al.Experimental is-sues with the two techniques have been discussed.5 Several conclusions can be drawn from these results:͑i͒When error bars of each point are taken into account,all three u s-u p data sets are in agreement.͑ii͒The CS-PC u s-u p data are in excellent mutual agreement,their error bars are less than half those of the L data,and the standard deviations of their jointfit are quite small.Thus,to compare experimentto theory,the u s-u pfit to the combined CS-PC data should betransformed to P-space.͑iii͒u s͑u p͒is weakly sensitive to dissociation;its slope du s/du p is sensitive to the onset ofdissociation at20GPa and less sensitive to its completionabove50GPa.͑iv͒Limiting compression of thefit to theCS-PC experimental data is4.30±0.10at100GPa.The cor-responding value of limiting compression calculated with PIMC and DFT is essentially4.3and it is4.0for an initially degenerate free-electron gas.The associated limiting slopes S lim are1.30and1.33,respectively.The slope of the CS-PC data is S3=1.22±0.08.D2Hugoniot data at100GPa pres-sures can barely resolve the presence of interactions.͑v͒Thus,kinetic thermal energy dominates potential energy at 100GPa shock pressures.͑vi͒Because interparticle potential energies become even smaller relative to thermal kinetic en-ergies at higher shock pressures,it is expected that the deu-terium Hugoniot agrees with PIMC and DFT calculations at higher shock temperatures and pressures,as well.Work at Lawrence Livermore National Laboratory was performed under the auspices of the U.S.Department of En-ergy by the University of California under Contract No. W-7405-Eng-48.Work at All-Russia Research Institute of Experimental Physics was partially supported by LLNL.We want to acknowledge M.D.Knudson for providing his ex-perimental data and M.P.Desjarlais for providing his calcu-lational results.*Present address:Department of Physics,Harvard University,Cam-bridge,MA02138.1L.B.Da Silva et 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23M.P.Desjarlais,Phys.Rev.B68,064204͑2003͒.24G.I.Kerley͑unpublished͒.25I.Kwon,J.D.Kress,and L.A.Collins,Phys.Rev.B50,9118͑1994͒.26G.Galli,R.Q.Hood,A.U.Hazi,and F.Gygi,Phys.Rev.B61, 909͑2000͒.27S.Bagnier,P.Blottiau,and J.Clerouin,Phys.Rev.E63, 015301͑R͒͑2002͒.28Of particular note is the work of Kerley͑Ref.24͒,who predicted the stiffer D2Hugoniot over thirty years ago before there were any experimental data available for shock-compressed liquid D2.。