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Formulation ofα-linolenic acid microemulsion free of co-surfactant

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Chinese Chemical Letters 2010年第1期21卷 105-108页

作者： feng Liu[a][b] Zheng Wu Wang[b] [a]School of Chemical Material Engineering Jiangnan University Wuxi 214036 China [b]School of Agriculture biology Shanghai Jiaotong University Shanghai 200240 China

A novel class ofα-linolenic acid-in-water microemulsion free of co-surfactant was investigated as potential food delivery *** demarcation within the transparent region was deduced from the results of conductivity and polarizing optical *** microemulsion mean hydrodynamic diameter and characterization were determined by dynamic light scattering and negative-staining *** location of ALA molecules in the microemulsion formulations was determined by ~1H NMR spectroscopy.

关键词： Microemulsion α-Linolenic acid Particle diameter ~1H NMR

Novel cobalt base superalloy and its high-temperature flow behavior

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Rare Metals 2008年第3期27卷 292-298页

作者： TANG Chunfeng PAN feng QU Xuanhui DUAN baihua WANG Tianjian HE Xinbo Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China School of Materials Science and Engineering UniversiO of Science and Technology Beijing Beijing 100083 China

A novel cobalt base superalloy containing titanium and aluminum was investigated through metallography, tensile test, and high-temperature isothermal compression deformation. The results show that proper content of titanium and aluminum with can improve the strength and ductility of the cobalt base superalloy. The Co3（Ti,Al） compound with L12 structure precipitates when the novel superalloy is aged at 800℃ for 20 h. The e phase with hcp structure also precipitates when the superalloy is deformed by 28% and then aged at 650℃ for 4 h. The e phase can exist at 800℃. The superalloy has excellent high-temperature mechanical properties. Its maximum flow stress at 850℃ is in the range of 360-475 MPa when the strain rate is between 0.0021 and 2.1 s^-1. The flow stress of the superalloy during high-temperature deformation can be described by the Zener-Hollomon parameter with a hot deformation activation energy of 397 ***^-1.

关键词： cobalt base supemlloy microstrcture heat treatment hot compression deformation

Vanadium recovery from clay vanadium mineral using an acid leaching method

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Rare Metals 2008年第2期27卷 116-120页

作者： LI Haoran feng Yali LIANG Jianglong LUO Xiaobing DU Zhuwei State Key Laboratory of biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China

A technique including direct acid leaching, vanadium precipitation with alkaline, sodium hydroxide releaching, impurity removing by adjusting pH value, precipitation vanadium with ammonium chloride, and vanadium pentoxide by roasting steps was proposed according to the characteristic of Xichuan clay vanadium mineral. The factors influencing leaching vanadium such as temperature and the concentration of sulfuric acid were investigated and optimized. The experimental results indicate that the extract ratios of V205 can reach 94% and 92% at a sodium chlorate ratio of 3% and a manganese dioxide ratio of 3%, respectivdy. A completely chemical precipitation method was adopted to decontaminate and enrich the vanadium in the acid leaching solution. The X-ray diffraction （XRD） pattern and the purity analysis of vanadium pentoxide indicate that the purity of final vanadium pentoxide can reach 99% and meet the standard specifications. The total recovery can reach about 75%. The technique has the characteristics of simplicity, less investment, and more environment safety as compared with the traditional salt roasting method.

关键词： clay vanadium mineral vanadium extraction acid leaching vanadium pentoxide

Advances in Isolation and Synthesis of Xanthone Derivatives

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Chinese Herbal Medicines 2012年第2期4卷 87-102页

作者： Chun-hui YANG[a] Li MA[b] Zhen-ping WEI[a] feng HAN[b] Jing GAO[b] School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Xanthone and its derivatives occupy a large part of the family of natural polyphenolic compounds with various biological and pharmacological *** recent years(from 2006 to 2011),it was reported that 127 xanthones were discovered from plants and fungi using various modern separation methods including silica gel/polyamide column chromatography,HPLC,high-speed counter-current chromatography,high-performance centrifugal partition chromatography,*** total synthesis and structure modification for xanthone and its derivatives have been given attention worldwide,we introduced the synthetic methods of xanthone skeletons as ***,to date,there are still weaknesses in current methods of separation and synthesis,which need to be *** review,to a certain extent,provides necessary foundation for the further research and development of medicines containing xanthone and its derivatives.

关键词： derivative HPLC isolation synthesis xanthones

A Quantitative Method for Simultaneous Determination of Four Anthraquinones with One Marker in Rhei Radix et Rhizoma

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Chinese Herbal Medicines 2012年第2期4卷 157-163页

作者： Jing-jing ZHU[a][b] Zhi-min WANG[a][b] Xin-yu MA[a] Wei-hong feng[a][b] Qi-wei ZHANG[a][b] Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China National Engineering Laboratory for Quality Control Technology of Chinese Herbal Medicines Beijing 100700 China

Objective To develop a quantitative method for simultaneously determining multi-components in Rhei Radix et Rhizoma using one chemical reference *** The contents of multi-components were calculated by the UV relative correction factors(RCFs)of chrysophanol,physcion,and rhein to *** The values of RCFs at 274 nm for rhein,chrysophanol,and physcion to emodin were 0.712,0.674,and *** calibration curves were linear over the ranges of 0.02-4.08,0.02-4.12,0.07-12.92,and 0.02-3.68μg/mL for rhein,emodin, chrysophanol,and physcion,*** contents of emodin in 18 samples were determined by the external standard method,and the contents of the other three anthraquinone aglycones were calculated according to their RCFs. Conclusion No significant difference is found in comparison with the classical method,indicating that the RCFs have high reliability within their linear ranges and could be used in quality control of Rhei Radix et *** quantitative analysis of multi-component with a single marker is especially suitable for herbal medicines containing unstable or hard to be purified components as quality control markers.

关键词： anthraquinone multi-component quantitative analysis quality control Rhei Radix et Rhizoma UV relative correction factor

Entropic stochastic resonance in a confined structure driven by dichotomous noise and white noises

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Chinese Physics b 2012年第8期21卷 71-77页

作者：郭锋程晓锋李少甫曹文黎恒 School of Information Engineering Southwest University of Science and Technology Research Center of Laser Fusion China Academy of Engineering Physics

The entropic stochastic resonance （ESR） in a confined system subjected to dichotomous noise and white noise and driven by a periodic sinusoidal force along the x axis of the structure and a time-dependent force in the declining direction, is investigated. Under the adiabatic approximation condition and based on the two-state theory, the expression of the output signal-to-noise ratio （SNR） is obtained. The results show that the SNR is a non-monotonic function of the strengths of dichotomous noise, white noise, and correlated strength of correlated noise. In addition, the SNR varies non-monotonically with the increase of the shape parameters of the confined structure, and also with the increase of the constant force along the y axis of the structure. The influence of the correlation rate of the dichotomous noise, and that of the frequency of the periodic force on the SNR are discussed.

关键词： entropic stochastic resonance dichotomous noise correlated noise square-wave signal,signal-to-noise ratio

Realistic Simulation of Rice Plant

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Rice science 2011年第3期18卷 224-230页

作者： Wei-long DING[a] Yu-ping ZHANG[b] Qian-yuan ZHANG[a] De-feng ZHU[b] Qi CHEN[a] [a]College of Computer Science & Technology Zhejiang University of Technology Hangzhou 310026 China [b]State Key Laboratory of Rice biology China National Rice Research Institute Hangzhou 310006 China

The existing research results of virtual modeling of rice plant, however, is far from perfect compared to that of other crops due to its complex structure and growth process. Techniques to visually simulate the architecture of rice plant and its growth process are presented based on the analysis of the morphological characteristics at different stages. Firstly, the simulations of geometrical shape, the bending status and the structural distortion of rice leaves are conducted. Then, by using an improved model for bending deformation, the curved patterns of panicle axis and various types of panicle branches are generated, and the spatial shape of rice panicle is therefore created. Parametric L-system is employed to generate its topological structures, and finite-state automaton is adopted to describe the development of geometrical structures. Finally, the computer visualization of three-dimensional morphologies of rice plant at both organ and individual levels is achieved. The experimental results showed that the proposed methods of modeling the three-dimensional shapes of organs and simulating the growth of rice plant are feasible and effective, and the generated three-dimensional images are realistic.

关键词： rice plant visualization geometric modeling architecture modeling rendering

H-and J-aggregation of conjugated small molecules in organic solar cells

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Journal of Energy Chemistry 2024年第6期93卷 174-192,I0005页

作者： Qiaoqiao Zhao feng He State Key Laboratory of biobased Material and Green Papermaking Qilu University of TechnologyShandong Academy of SciencesJinan 250353ShangdongChina Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055GuangdongChina Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055GuangdongChina

As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC *** this end,this review is ***,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in ***,the characteristics of H-and J-aggregation and the methods to identify them were ***,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance.

关键词： H-aggregation J-aggregation Organic solar cells Small molecules Efficiency Stability

Turbulence Statistics of Thermo-buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： SUN feng XIE Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection *** existence of buoyancy force would lead to strongly anisotropic flow and thermal transport *** is closely related to the cooling performance of the *** elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence *** results indicated that the buoyancy and inertial force together dominated the change of turbulent ***,the spatial thermal buoyancy effect significantly suppressed the vertical velocity *** is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal *** the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,*** the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more *** thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer *** results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics