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Achieving high carrier mobility and low lattice thermal conductivity in GeTe-based alloys by cationic/anionic co-doping

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Rare Metals 2024年第6期43卷 2784-2795页

作者： xiao-Qiang wang xiao-Quan Hu Jun-Yan Lin Chu-Bin Li xiao-Tong Yu Qi-Yong Chen Li-Li Xi Qi-Shuo Yang Han Li Ji-Ye Zhang Shuan-Kui Li Kai Guo School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research&Graduate School of Guangzhou UniversitySino-Singapore Guangzhou Knowledge CityGuangzhou510555China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLD 4072Australia Key Laboratory of Si-Based Information Materials&Devices and Integrated Circuits Design Department of Education of Guangdong ProvinceGuangzhou 510006China

TheⅣ-Ⅵcompound GeTe is considered as a promising alternative to the toxic PbTe for high-efficiency mid-temperature thermoelectric ***,pristine GeTe suffers from a high concentration of Ge vacancies,resulting in an excessively high hole concentration(>1×10^(21)cm^(-3)),which greatly limits its thermoelectric *** address this issue,CuBiTe_(2)alloying is introduced to increase the formation energy of Ge vacancies in GeTe,thereby inhibiting the high carrier *** carrier scattering caused by the electronegativity difference between different elements is suppressed due to the similar electronegativity of Cu and Ge atoms.A relatively high hole mobility is obtained,which ultimately leads to a high power ***,by introducing Se as an alloying element at the anionic site in GeTe,dense point defects with mass/strainfield fluctuations are *** contributes to the strengthening of phonon scattering,thereby reducing the lattice thermal conductivity from 1.44 W·m^(-1)·K^(-1)for pristine GeTe to 0.28 W·m^(-1)·K^(-1)for Ge_(0.95)Cu_(0.05)Bi_(0.05)Te_(0.9)Se_(0.15)compound at 623 K.

关键词： GeTe Carrier mobility CuBiTe_(2)alloying Lattice thermal conductivity Thermoelectric properties

Reservoir heterogeneity controls of CO_(2)-EOR and storage potentials in residual oil zones:Insights from numerical simulations

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Petroleum Science 2023年第5期20卷 2879-2891页

作者： Yan-Yong wang xiao-Guang wang Ren-Cheng Dong Wen-Chao Teng Shi-Yuan Zhan Guang-Yong Zeng Cun-Qi Jia College of Energy Chengdu University of TechnologyChengdu610059SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Engineering Research Center of Geothermal Resources Development Technology and Equipment Ministry of EducationJilin UniversityChangchun130026JilinChina The University of Texas at Austin AustinTX78712USA Department of Energy Resources Engineering Stanford UniversityStanfordCA94305USA State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059SichuanChina

Residual oil zones(ROZs)have large potential for CO_(2)enhanced oil recovery(EOR)and geologic *** CO_(2)injection,the migration of CO_(2)in ROZs controls the performance of both EOR and ***,it has not been clearly visualized and understood that how geological heterogeneity factors control the transport of CO_(2)in *** this study,the oil recovery performance and geologic storage potential during continuous CO_(2)injection in a representative ROZ are studied based on geostatistical modelling and high-fidelity three-phase flow *** examined the influence of autocorrelation length of permeability,global heterogeneity(DykstraeParsons coefficient),and permeability anisotropy on cumulative oil recovery and CO_(2)retention *** results indicate that,as the permeability autocorrelation length increases,the cumulative oil recovery and CO_(2)storage efficiency *** results from the accelerated migration of CO_(2)along high permeability zones(i.e.,gas channeling).The increase in global heterogeneity and permeability anisotropies can lead to low oil recovery and poor CO_(2)sequestration performance,depending on the degree of CO_(2)*** net utilization ratio of CO_(2)(CO_(2)retained/oil produced)unfavorably increases with both autocorrelation length and Dykstra eParsons coefficient,but decreases with the increase in kv/*** a decrease is attributed to enlarged swept volume induced by gravity *** study provides important implications for fieldscale CO_(2)EOR and storage applications in ROZs.

关键词： Residual oil zones CO_(2)injection Enhanced oil recovery Geologic sequestration

Quantification of Erdosteine in the Low-volume of Dog Plasma by Liquid Chromatography Tandem Mass Spectrometry

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Chemical Research in Chinese Universities 2007年第6期23卷 736-741页

作者： LIU Dan wang Yan TANG Yun-biao CHEN xiao-yan ZHONG Da-fang Laboratory of Drug Metabolism and Pharmacokinetics Shenyang Pharmaceutical University Shenyang 110016 P. R. China The First Hospital of Jilin University Changchun 130021 P. R. China Department of Pharmacy General Hospital of Shenyang Military Region Shenyang 110015 P. R. China Center for Drug Metabolism and Pharmacokinetics Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 P. R. China

Introduction Erdosteine [ N-（ carboxymethylthioacetyl ）-homocysteine thiolactone ] （ Fig. 1 ） is a synthetic derivative of natural amino acid methionine. It has been commonly used in clinical practice as a mucolytic drug and as an enhancer of respiratory ventilation in the treatment of patients with chronic obstructive respiratory disease. Erdosteine contains 2 blocked sulfhydryl groups, which are released after metabolic transformation in the liver. The liberated sulfhydryl groups break the disulphide bonds, which hold the glycoprotein fibres of mucus together; this makes the bronchial secretions more fluid and allows more rapid elimination. The reducing potential of these sulfhydryl groups accounts for the free radical scavenging and antioxidant properties of erdosteine.

关键词： Erdosteine Dog plasma Pharmacokinetics HPLC/MS/MS

Application of the SCS-CN Model to Runoff Estimation in a Small Watershed with High Spatial Heterogeneity

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Pedosphere 2011年第6期21卷 738-749页

作者： xiao Bo wang Qing-Hai FAN Jun HAN Feng-Peng DAI Quan-Hou Beijing Research ＆ Development Center for Grass and Environment Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 （China） State Key Laboratory of Soil Erosion and Dryland Farmning on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 （China） Colleqe of Forest Guizhou University Guiyang 550025 （China）

For reasons of simplicity, the most commonly used hydrological models are based on the Soil Conservation Service Curve Number （SCS-CN） model, which is probably a good choice for the estimation of runoff on the Loess Plateau of China; however, the high spatial heterogeneity, mainly caused by a fragmented landform and variations in soil type, may limit its applicability to this region. Therefore, applicability of the SCS-CN model to a small watershed, Liudaogou on the plateau, was evaluated and the most appropriate initial abstraction ratio （I~/S） value in the model was quantified by the inverse method. The results showed that the standard SCS-CN model was applicable to the estimation of runoff in the Liudaogou watershed and the model performance was acceptable according to the values of relative error and Nash-Sutcliffe efficiency. The most appropriate Ia/S value for the watershed was 0.22 because with this modified Ia/S value, the model performance was slightly improved. The model performance was not sensitive to the modification of the Ia/S value when one heavy rainfall event （50.1 mm） was not considered, which implied that the model, using a standard Ia/S value, can be recommended for the Liudaogou watershed because single rainfall events exceeding 50 mm seldom occurred in that region. The runoff amount predicted for the Liudaogou watershed by the SCS-CN model, using the modified Ia/S value, increased gradually with increasing rainfall when rainfall values were lower than 50 mm, whereas the predicted amount increased rapidly when the rainfall exceeded 50 mm. These findings may be helpful in solving the problem of serious soil and water loss on the Loess Plateau of China.

关键词： curve number initial abstraction ratio model performance rainfall soil and water loss

Volatile profile analysis and quality prediction of Longjing tea(Camellia sinensis) by HS-SPME/GC-MS

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第12期13卷 972-980页

作者： Jie LIN Yi DAI Ya-nan GUO Hai-rong XU xiao-chang wang Institute of Tea Science Zhejiang UniversityHangzhou 310058China College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China

This study aimed to analyze the volatile chemical profile of Longjing tea, and further develop a prediction model for aroma quality of Longjing tea based on potent odorants. A total of 21 Longjing samples were analyzed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS).Pearson's linear correlation analysis and partial least square (PLS) regression were applied to investigate the relationship between sensory aroma scores and the volatile compounds. Results showed that 60 volatile compound scould be commonly detected in this famous green tea. Terpenes and esters were two major groups characterized,representing 33.89% and 15.53% of the total peak area respectively. Ten compounds were determined to contribute significantly to the perceived aroma quality of Longjing tea, especially linalool (0.701), nonanal (0.738), (Z)-3-hexenyl hexanoate (-0.785), and β-ionone (-0.763). On the basis of these 10 compounds, a model (correlation coefficient of89.4% and cross-validated correlation coefficient of 80.4%) was constructed to predict the aroma quality of Longjingtea. Summarily, this study has provided a novel option for quality prediction of green tea based on HS-SPME/GC-MStechnique.

关键词： Partial least square (PLS) regression Green tea Headspace solid phase microextraction (HS-SPME) Volatile profile Quality prediction

Enhanced mechanical properties of linear segmented shape memory poly（urethane-urea） by incorporating flexible PEG400 and rigid piperazine

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Frontiers of Materials Science 2012年第4期6卷 326-337页

作者： xiao-Yan ZHANG Yu-Fei MA Yong-Gang LI Pin-Pin wang Yuan-Liang wang Yan-Feng LUO Key Lab of Biorheological Science and Technology(Ministry of Education) Research Center for Bio-inspired Material Science and EngineeringCollege of BioengineeringChongqing UniversityChongqing 400030China

The goal of this study is to design and synthesize a linear segmented shape memory poly（urethane-urea）（SMPUU） that possesses near-body-temperature shape memory temperature （Ttran） and enhanced mechanical properties by incorporating flexible poly（ethylene glycol） 400 （PEG400） to form poly（D,L-lactic acid）-based macro- diols （PDLLA-PEG400-PDLLA） and then rigid piperazine （PPZ） as a chain extender to form the desired SMPUUs （PEG400-PUU-PPZ）. PEG400 increased Mn while maintaining a lower Tg of PDLLA-PEG400-PDLLA, which together with PPZ improved the mechanical properties of PEG400-PUU-PPZ. The obtained optimum SMPUU with enhanced mechanical properties （O＇y = 24.28 MPa; zf = 698%; Uf = 181.5 MJIm3） and a Tg of 40.62~C exhibited sound shape memory properties as well, suggesting a promising SMPUU for in vivo biomedical applications.

关键词： poly(urethane-urea) poly(D,L-lactic acid) poly(ethylene glycol) piperazine,shape memory property mechanical property

Preliminary Research on Cd^(2+) Removal from Wastewater by Sphaerotilus Natans

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Chemical Research in Chinese Universities 2005年第6期21卷 654-657页

作者： QIN Yu-chun GUAN xiao-hui YIN Rong wang Li-wen WEI De-zhou School of Resources and Civil Engineering Northeastern University Shenyang 110004 P. R. China Department of Applied Chemistry Northeast Institute of Electric Power Engineering Jilin 132012 P. R. China Department of Common Courses Beihua University Jilin 132011 P. R. China

Influencing factors, such as the biomass concentration, pH value, temperature and time of adsorption on the removal of Cd^2＋ were investigated when Sphaerotilus natans was used as a biosorbent. The results show that Sphaerotilus natans has a significant effect on the adsorption of Cd^2＋. The process of adsorption will reach the equilibrium in 20 min. Temperature has no significant effect on the adsorption. The removal rate of Cd^2＋. can approach to 90% under the conditions of pH 5.5, the biomass mass concentration O. 6 g/L and the initial mass concentration of cadmium ≤20 mg/L. The maximum specific uptake is 1.9 mmol/g dry biomass . The adsorption was fitted with the Freundlich isotherm adsorption equation when the concentration of Cd^2＋ is in a range of 0--100 mg/L. HCl and EDTA can desorb Cd^2＋ from biomass effectively.

关键词： Sphaerotilus natans Cadmium ion Adsorption character Influencing factor

A fuzzy formal concept analysis based approach for business component identification

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第9期12卷 707-720页

作者： Zhen-gong CAI xiao-hu YANG Xin-yu wang Aleksander J. KAVS School of Computer Science and Technology Zhejiang University Hangzhou 310027 China StateStreet Corporation Boston MA 02111 USA

Identifying business components is the basis of component-based software engineering. Many approaches, including cluster analysis and concept analysis, have been proposed to identify components from business models. These approaches classify business elements into a set of components by analyzing their properties. However, most of them do not consider the difference in their properties for the business elements, which may decrease the ac- curacy of the identification results. Fhrthermore, component identification by partitioning business elements cannot reflect which features are responsible for the generation of certain results. This paper deals with a new approach for component identification from business models using fuzzy formal concept analysis. First, the membership between business elements and their properties is quantified and transformed into a fuzzy formal context, from which the concept lattice is built using a refined incremental algorithm. Then the components are selected from the concepts according to the concept dispersion and distance. Finally, the effectiveness and efficiency are validated by applying our approach in the real-life cases and experiments.

关键词： Business component identification Formal concept analysis Business model Concept clustering Fhzzy concept

Pinhole imaging to observe spatial jitters of a triple-pulse X-ray source on the Dragon-Ⅱ LIA

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Nuclear Science and Techniques 2016年第5期27卷 140-145页

作者： Yi wang Zhi-Yong Yang xiao-BingJing Qin Li Heng-Song Ding Zhi-Yong Dai Key Laboratory of Pulsed Power Institute of Fluid Physics China Academy of Engineering Physics Mianyang 621900 China

In high-energy flash radiography,scattered photons degrade the acquiring image,which limits the resolving power of interfaces and density of dense *** application of large anti-scatter grid can reduce the scattered photons remarkably,but this requires a stable source position in order to reduce the loss of signal photons in the grid *** pinhole imaging technique is applied to observe spatial jitters of a triple-pulse radiographic source of a linear induction *** simulations are conducted to analyze the imaging performance with the same or close parameters of the pinhole object and experimental *** are carried out to observe spatial jitters of the source between different *** of the source position between different pulses are measured in each experiment.

关键词：针孔成像 X射线源空间脉冲直线感应加速器抖动高能闪光照相散射光子