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Ion Product of Pure Water Characterized by Physics-Based Water Model
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作者 揭斌斌 蕯支唐 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第2期167-170,I0001,共5页
Pure water has been characterized for nearly a century, by its dissociation into hydronium (H3O)1+ and hydroxide (HO)1- ions. As a chemical equilibrium reaction, the equilibrium constant, known as the ion product... Pure water has been characterized for nearly a century, by its dissociation into hydronium (H3O)1+ and hydroxide (HO)1- ions. As a chemical equilibrium reaction, the equilibrium constant, known as the ion product or the product of the equilibrium concentration of the two ion species, has been extensively measured by chemists over the liquid water temperature and pressure range. The experimental data have been nonlinear least-squares fitted to chemical thermodynamic-based equilibrium equations, which have been accepted as the industrial standard for 35 years. In this study, a new and statistical-physics-based water ion product equation is presented, in which, the ions are the positively charged protons and the negatively charged proton-holes or prohols. Nonlinear least squares fits of our equation to the experimental data in the 0-100℃ pure liquid water range, give a factor of two better precision than the 35-year industrial standard. 展开更多
关键词 Solid state physics Liquid state chemistry Pure water ion product Positiveproton Negative proton-hole or prohol
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Production of radioactive ~9C ion beam and its optimization 被引量:3
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作者 WEIZeng-Quan LIQiang +5 位作者 A.KITAGAWA T.KANAI M.KANAZAWA E.URAKABE XIEHong-Mei ZHOUGuang-Ming 《Nuclear Science and Techniques》 SCIE CAS CSCD 2005年第2期95-98,共4页
To explore the medical use of a radioactive 9C-ion beam in tumor treatment, which is a double radiation source coming from the external beam itself and the delayed particles emitted internally, some physical experimen... To explore the medical use of a radioactive 9C-ion beam in tumor treatment, which is a double radiation source coming from the external beam itself and the delayed particles emitted internally, some physical experiments are performed at the Secondary Beam Line (SBL) of Heavy Ion Medical Accelerator, Chiba (HIMAC) in Japan be- fore radiobiological research for exhibiting therapeutic value of the 9C beam. Intention of the experiments is for pro- ducing a radioactive 9C-ion beam with higher production rate and purity by means of optimizing the beam line pa- rameters. Finally, a produced 9C beam with the production rate of 9.07×10-6 and purity of 82.88% at full momentum acceptance has been obtained under the optimal conditions of 40 mm-thick beryllium target and 10 mm-thick alumi- num degrader. Both momentum distribution and contaminations for the produced 9C beam under the optimal condi- tions are measured. In order to execute further biological experiments of the 9C beam project, a uniform irradiation field is made with the wobbling magnets and its homogeneity is up to 93.8% inside central area of 20mm in diameter. 展开更多
关键词 放射性离子束 参数优化 肿瘤治疗 放射医学
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Removal of chloride from simulated acidic wastewater in the zinc production 被引量:3
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作者 Weizao Liu Li Lu +2 位作者 Yao Lu Xiaowei Hu Bin Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1037-1043,共7页
The removal of chloride from the zinc electrolyte produced during hydrometallurgical zinc production is challenging. The ion-exchange method is a promising way to remove chloride if the resin washing wastewater can be... The removal of chloride from the zinc electrolyte produced during hydrometallurgical zinc production is challenging. The ion-exchange method is a promising way to remove chloride if the resin washing wastewater can be recycled. This paper focuses on chloride removal from resin washing wastewater to enable its reuse. Various processing factors including the oxygen gas velocity, temperature, and reaction time were investigated systematically. The results show that the optimal conditions for dechlorination are an oxygen gas velocity of 0.5 L-min^-1, a reaction temperature of 80 ℃, and a reaction time of 30 min. A dechlorination efficiency of 80% with a residual chloride ion concentration less than 200 mg-L^-1 was achieved, which meets the requirements for the recycling of wastewater. The presence of manganese accelerates the dechlorination by forming a Mn^2+- MnO^2-MnO4^-Mn^2+ redox cycle. In this process, about 15 kg of the MnO2 and all of the zinc can be recovered from 100 m^3 wastewater, and the wastewater can be reused, which makes the ion-exchange method a promising technique for chloride removal. 展开更多
关键词 ion-exchange DECHLORINATion OZONE ZINC production Oxidation
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Multiplicity dependence of charged particle,? meson, and multistrange particle productions in p + p collisions at s^(1/2) = 200 GeV from PYTHIA simulation 被引量:2
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作者 Sheng-Hui Zhang Long Zhou +5 位作者 Yi-Fei Zhang Ming-Wei Zhang Cheng Li Ming Shao Yong-Jie Sun Ze-Bo Tang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期236-241,共6页
We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multipl... We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multiple parton interactions and gluon contributions is studied and found to be a possible source of the splitting of the particle yields as a function of p_T with respect to the multiplicity. No obvious particle species dependence of the splitting is observed.The multiplicity dependence of the ratios Kˉ/πˉ, K^+/π^+,/πˉ, p/π^+, and K_s^0 at mid-rapidity in p+ p collisions is found to follow a tendency similar to that in Au t Au collisions at (s_(NN))^(1/2) = 200 GeV at the Relativistic Heavy Ion Collider, indicating similar underlying initial production mechanisms despite the differences in the initial colliding systems. 展开更多
关键词 Particle production HEAVY-ion COLLISionS Small system Multiple PARTON interactions GLUON contributions
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On Production of Hadrons in Proton-Proton Collisions at RHIC and LHC Energies and an Approach
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作者 P. Guptaroy Goutam Sau S. Bhattacharyya 《Journal of Modern Physics》 2012年第1期116-123,共8页
From the very early days of Particle Physics, both experimental and theoretical studies on proton-proton collisions had occupied the center-stage of attention for very simple and obvious reasons. And this intense inte... From the very early days of Particle Physics, both experimental and theoretical studies on proton-proton collisions had occupied the center-stage of attention for very simple and obvious reasons. And this intense interest seems now to be at peak value with the onset of the Large Hadron Collider (LHC)-studies at TeV ranges of energies. In this work, we have chosen to analyse the inclusive cross-sections, the rapidity density, the and -ratio behaviours and the r > -values, in the light of the Sequential Chain Model (SCM). And the limited successes of the model encourage us to take up further studies on several other aspects of topmost importance in particle physics with the same approach. 展开更多
关键词 Relativistic Heavy ion COLLISionS INCLUSIVE production
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Production and Quality Control of <sup>64</sup>Cu from High Current Ni Target
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作者 A. H. Al Rayyes Y. Ailouti 《World Journal of Nuclear Science and Technology》 2013年第2期72-77,共6页
A new production method of no-carrier-added 64Cu was tested using a new target prepared by electroplating of Ni on a silver layer (thickness 35 μm) previously electroplated on a pure copper target support. This metho... A new production method of no-carrier-added 64Cu was tested using a new target prepared by electroplating of Ni on a silver layer (thickness 35 μm) previously electroplated on a pure copper target support. This method meets cost effective production and quality of the produced 64Cu criteria. The quality of the electroplated layers has been tested under the bombardment by more than 200 μA of proton beam using water cooled target system. A separation and purification setup was elaborated to produce high quantity and high specific activity of 64CuCl2 suitable for labeling different ligands in order to be used in therapy and diagnosis. A semi-automated target dissolution and separation system has been developed and achieved for 64Cu production. The separation chemistry is based on a chromatographic column system. 展开更多
关键词 64Cu Targetry RADIOISOTOPE production ion EXCHANGE CHROMATOGRAPHY
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Production of Superoxide Ion with Carbon Gas-Diffusion-Electrode And Reaction of Superoxide Ion with Aromatic Halide
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作者 Shu Fang WANG, Chu Bao HUANG and Dong ZHANG (Department of Chemistry, Jilin University, Changchun, 130023) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期827-828,共2页
Superoxide ion O^-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O^... Superoxide ion O^-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O^-_2 with p-bromonitrobenzene. When the gas-diffussion-electrode is used, the yield of the product nitrophenol increases by 20%, and the selectivity of the reaction is nearly doubled as compared with the plane-electrode. 展开更多
关键词 production of Superoxide ion with Carbon Gas-Diffusion-Electrode And Reaction of Superoxide ion with Aromatic Halide
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Detection of Cyanide in Pollution-free Livestock Product Breeding Water by Ion Chromatography 被引量:3
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作者 Dongya HUANG Youkai PENG Jinting YAN 《Asian Agricultural Research》 2018年第1期34-36,共3页
In order to verify the accuracy of ion chromatography for cyanide detection,optimization conditions were studied,and comparison was made for the detection results of cyanide between titration and isonicotinic acid pyr... In order to verify the accuracy of ion chromatography for cyanide detection,optimization conditions were studied,and comparison was made for the detection results of cyanide between titration and isonicotinic acid pyrazolone spectrophotometry. The results showed that ion chromatography has good linearity and reproducibility,with the recovery rate of 95%-105% and the limit of detection of 0. 001 mg/L. This method is simple,rapid,safe,selective,and suitable for the determination of cyanide in pollution-free livestock product breeding water. 展开更多
关键词 ion chromatography TITRATion SPECTROPHOTOMETRY Pollution-free livestock product breeding water CYANIDE
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Production of J/Ψ-Particles at RHIC and LHC Energies: An Alternative “Psi”-Chology
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作者 P. Guptaroy Goutam Sau +1 位作者 S. K. Biswas S. Bhattacharyya 《Open Journal of Microphysics》 2012年第2期19-26,共8页
We attempt here to understand successfully some crucial aspects of J/Ψ-production in some high energy nuclear collisions in the light of a non-standard framework outlined in the text. It is found that the results arr... We attempt here to understand successfully some crucial aspects of J/Ψ-production in some high energy nuclear collisions in the light of a non-standard framework outlined in the text. It is found that the results arrived at with this main working approach here is fairly in good agreement with both the measured data and the results obtained on the basis of some other models of the ‘standard’ variety. Impact and implications of this comparative study have also been precisely highlighted in the end. 展开更多
关键词 Relativistic Heavy ion Collisions INCLUSIVE production Charmed MESON
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Effect of Sodium Ion Concentration on Hydrogen Production from Sucrose by Anaerobic Hydrogen-producing Granular Sludge
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作者 郝小龙 周明华 +2 位作者 俞汉青 沈琴琴 雷乐成 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4X期511-517,共7页
This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the op... This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the opti- mum sodium ion concentration [1000—2000mg·L-1(Na+)] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6— 413.1mg·L-1·h-1, 28.04—28.97ml·g-1, 7.52—7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration. 展开更多
关键词 sodium ion concentration anaerobic fermentation hydrogen production SUCROSE volatile fatty acids up-flow anaerobic sludge blanket (UASB) reactor
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Nuclear dynamics and particle production near threshold energies in heavy-ion collisions 被引量:12
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作者 Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期107-137,共31页
Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect... Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF). 展开更多
关键词 LQMD transport model HEAVY-ion REACTionS Hadron-induced NUCLEAR REACTionS Symmetry energy STRANGENESS production
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Superheavy Particle Production in High Energy Heavy Ion Collisions
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作者 Alexey Kurepin 《Journal of Modern Physics》 2021年第4期433-439,共7页
The existence of several TeV superheavy particles (SHPs) is predicted by theories beyond the Standard Model. Particles with a mass exceeding the energy in the center of mass in the collision of protons with protons ca... The existence of several TeV superheavy particles (SHPs) is predicted by theories beyond the Standard Model. Particles with a mass exceeding the energy in the center of mass in the collision of protons with protons can be produced in subthreshold heavy ion collisions at the LHC. The purpose of the performed research was to estimate the rate of a rare process of SHPs production. It was shown that the data on the subthreshold production of antiprotons can be explained by the phenomenological parton model. The obtained parton distribution function was used to determine the number of SHPs produced in subthreshold heavy ion collisions at the LHC. In one month of collision of lead with lead, the yield of 16 TeVparticles is about 70 per year. To study the kinematically forbidden phenomena in proton-proton interactions in collisions of heavy nuclei at the LHC, an experiment on the production of antiprotons is proposed in the ALICE fixed target project. 展开更多
关键词 Particle Physics Heavy ion Collisions Parton Model Antiproton production
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Dilepton production in baryon-rich quark-gluon matter
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作者 He Ze-Jun Zhang Jia-Ju Jiang Wei-Zhou and Liu Bo (CCAST World Laboratory P. O. Box 8730, Beijing 100080)(Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800)(Computing Center of Shanghai Branch, the Chinese Academy o 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第2期65-68,共4页
From the full stopping scenario and considered the Drell-Yang background, the rapidity dependence of the dilepton production from the central collision 197Au + 197Au has been studied in the baryon-rich quark-gluon mat... From the full stopping scenario and considered the Drell-Yang background, the rapidity dependence of the dilepton production from the central collision 197Au + 197Au has been studied in the baryon-rich quark-gluon matter by using a relativistic hydrodynamic model.It can be found that the dilepton yield is strongly suppressed as increasing the rapidity. Such a characteristic signaling the formation of the baryon-rich quark-gluon matter can be tested in future experiments at CERN and Brookhaven. 展开更多
关键词 重离子 夸克胶子物质 轻子产生
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Influence of Metal Ions on Hydrogen Production by Photosynthetic Bacteria Grown in Escherichia coli Pre-Fermented Cheese Whey
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作者 Fadhil M. Salih Muthana I. Maleek 《Journal of Environmental Protection》 2010年第4期426-430,共5页
The photosynthetic bacteria, Rodospirillum rubrum, produced hydrogen when grown in cheese whey in presence of light. The production increased three times as much when whey was used after being incubated in presence of... The photosynthetic bacteria, Rodospirillum rubrum, produced hydrogen when grown in cheese whey in presence of light. The production increased three times as much when whey was used after being incubated in presence of Escherichia coli at 37℃ for 5 days, giving a total of 3600 ml of H2 in 10 days. The presence of Fe ions (5 mg/L) enhanced H2 production of treated whey to about 6000 ml in 10 days. Mo ions (0.3 and 1.6 mg/l) did not affect achieved H2 production of treated whey. However, when Fe and Mo ions were present together, the production was comparable with that of Mo ions alone, i.e. Mo prevented Fe of producing any enhancing effect. The addition of Mn ions (7.68 mg/L) to treated whey containing Fe (5 mg/L) and Mo ions (8 mg/L) increased H2 production to give about 9500 ml/10 days. 展开更多
关键词 Hydrogen production PHOTOSYNTHETIC Bacteria Rodospirillum rubrum Metal ions E. COLI Fermentation
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Transtarget residue products of 47 MeV/u ^(12)C ions on ^(133)Cs targets
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作者 LiZong-Wei YangWei-Fan 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第3期183-185,共3页
Transtargetresidueproductsof47MeV/u12Cionson133CstargetsLiZongWei,YangWeiFanandZhaoZhiZheng(InstituteofModer... Transtargetresidueproductsof47MeV/u12Cionson133CstargetsLiZongWei,YangWeiFanandZhaoZhiZheng(InstituteofModernPhysics,theC... 展开更多
关键词 重离子 12C离子 133Cs靶 反应产物
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Entropy Production and Fractal Dimensions in Heavy Ion Nuclear Reaction at Intermediate Energies
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作者 Wenxia Wang Yiyan Zhao Yongzhong Xing 《Journal of Applied Mathematics and Physics》 2022年第8期2527-2537,共11页
The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized Entropy (GE) and the Multifragmentation Entrop... The characteristics of the nonlinear dynamics in the Heavy Ion Collision (HIC) at intermediate energies have been studied by evaluating the productions of the Generalized Entropy (GE) and the Multifragmentation Entropy (ME) as well as the features of the information and fractal dimensions within the Isospin Quantum Molecular Dynamical Model compensated by the lattice methods. Results demonstrate from various views that the existence of deterministic chaos in the dynamical process of reaction. 展开更多
关键词 Entropy production Fractal Dimensions Chaotic Behavior Heavy ion Nuclear Collision Intermediate Energy
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基于多壁碳纳米管/Nafion修饰电极的溶出伏安法测定大豆和大米重金属铅含量 被引量:4
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作者 王忠政 洪琦 《中国油料作物学报》 CAS CSCD 北大核心 2020年第3期350-355,共6页
建立了一种测定大豆和大米中重金属铅含量的多壁碳纳米管/Nafion溶出伏安方法。该方法对重金属铅的线性方程为y=4.66x+46.19,相关系数为0.994,线性范围0.1~20.0μmol/L。实际样品测试中多壁碳纳米管/Nafion材料对大豆中铅的样品回收率为... 建立了一种测定大豆和大米中重金属铅含量的多壁碳纳米管/Nafion溶出伏安方法。该方法对重金属铅的线性方程为y=4.66x+46.19,相关系数为0.994,线性范围0.1~20.0μmol/L。实际样品测试中多壁碳纳米管/Nafion材料对大豆中铅的样品回收率为99.50%~100.37%,相对标准偏差小于5.36%;对大米中铅的回收率为98.75%~101.25%,相对标准偏差小于5.63%。该方法可适用于大豆和大米为主的粮油产品中重金属铅的检测,为加强食品安全保障提供技术支撑。 展开更多
关键词 多壁碳纳米管 Nafion分散液 重金属铅 粮油产品
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Differentiation of Four Pairs of Isomers by Comparing Their Relative Abundances of Fragment Ions
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作者 SUN Ming-qian LU Jian-qiu +3 位作者 ZHANG Hong-gui ZHANG Qun-shu XIAO Nan Rui-yun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期27-32,共6页
Based on the LC-ESI/MSn technique, the four pairs of isomers of psoralen and isopsoralen, imperatorin and isoimperatorin, neohesperidin and hesperidin, naringin and narirutin were distinguished mainly by comparison of... Based on the LC-ESI/MSn technique, the four pairs of isomers of psoralen and isopsoralen, imperatorin and isoimperatorin, neohesperidin and hesperidin, naringin and narirutin were distinguished mainly by comparison of the relative abundances of their major fragment ions. Because of the effect of the hydrogen on the C8 of psoralen, the intensity of the fragment ion formed by the loss of CO2 was relatively increased. By comparing the abundance of the product ions formed by the loss of CO and 2CO, the isomers of psoralen and isopsoralen could be distinguished. This method can also be used to distinguish the isomers of imperatorin and isoimperatorin. Because of the different con- nected position between glucose and rhamnose, in the mass spectrum of neohesperidin, the relative abundances of ions at m/z 489 and 343 generated by the ring-cross cleavage of glycan were more than 10%, while in the mass spec- trum of hesperidin, they were all less than 1%. This approach can also be used to distinguish the isomers ofnaringin and narirutin. Although the fragmentation pathways were similar, according to the tiny difference of structure, the change of relative intensity of main fragment ions could be observed and it could be used to distinguish some isomers more accurately and quickly. 展开更多
关键词 LC-MSn Relative abundance ISOMER product ion Generation opportunity
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Deterioration Mechanisms of Sulfate Attack on Concrete under Alternate Action 被引量:8
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作者 高润东 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第2期355-359,共5页
By micro- and macro-observations, the deterioration mechanisms of concrete under alternate action between repeated sub-high temperature/cooling by water and sodium sulfate solution attack (TW-SA) were studied; meanw... By micro- and macro-observations, the deterioration mechanisms of concrete under alternate action between repeated sub-high temperature/cooling by water and sodium sulfate solution attack (TW-SA) were studied; meanwhile, the single sodium sulfate solution attack (SA) was also done as comparison. Micro-observations included the analysis of attack products by thermal analysis method and the determination of sulfate-ion content from surface to interior by chemical titrating method (modified barium sulfate gravimetric method). Macro-observations mainly included the mechanical behaviors such as compressive strength, splitting strength. The experimental results indicate, in both cases, the main attack product is ettringite, only in the first layer of case SA some gypsum is checked; in case SA, the sulfate ions mainly concentrate in the surface layer, so the attack is relatively mild; but in case TW-SA, the repeated sub-high temperature/cooling by water promotes the sulfate ions diffusing inwards, which leads to obvious strength degradation. 展开更多
关键词 CONCRETE SULFATE repeated sub-high temperature/cooling by water attack product sulfate-ion content strength
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New developments at nuclear emulsion experiment
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作者 QianWan-Yan CaiXu 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第4期213-217,共5页
Three new nuclear cmulsion techniques used for measuring emission angles ofcharged particles in central events at ultra-high evergy heavy-ion collisions are fully described.
关键词 重离子 多粒子产生 原子核 乳胶实验
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