检索结果-南通市图书馆

Chinese Journal of Polymer Science 2016年第1期34卷 77-87页

作者： Xiang Luo shi-jie xie 黄卫 Bo-na Dai 吕中元 De-yue Yan School of Che-mistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China Institute of Theoretical Chemistry StateKey Laboratory of Supramolecular Structure and MaterialsJilin UniversityChangehun 130021China Instrumental Analysis Center Shanghai Jiao Tong UniversityShanghai 200240China

By controlling the feed ratio of CMS/styrene and the polymerization time, a series of hyperbranched copolystyrenes（HBCPS） were synthesized with comparable weight-averaged molecular weights（Mw） but different degree of branching（DB） through atom transfer radical self-condensing vinyl copolymerization（ATR-SCVCP） with Cu Br/2,2？-bipyridyl as the catalyst. The resulting HBCPS samples were used to investigate the effect of branching architecture on their glass transition behavior. With the DB increased, the glass transition temperatures（Tg） of HBCPS samples measured by DMA and DSC both decreased. Their spin-lattice relaxation times（1H T1r） of protons displayed the same downtrend with increasing DB. Besides, a correlation between the Tgs and the DB was well established by all-atom molecular dynamics（MD） simulations. The values of MD-determined Tgs are little higher than the corresponding experimental ones. However, the dependence of Tgs on DB is in good agreement with the experimental results, i.e., Tg decreases both in experiments and simulations with increasing DB.

关键词： All-atom molecular dynamics simulation Degree of branching Glass transition temperature Hyperbranched copolystyrene

Influence of Heat-setting Temperature on the Microporous Structure and Properties of PP/HDPE Bilayer Microporous Membranes

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第8期42卷 1243-1252页

作者： jie xie Yong-shi Wu Jia-Yi xie Rui-jie Xu Cai-Hong Lei Sai-Nan Song Guang-Quan Li An-Ping Huang School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China Lanzhou Petrochemical Research Center Petrochemical Research InsititutePetroChinaLanzhou 730060China School of Chemistry and Civil Engineering Shaoguan CollegeShaoguan 512005China

Due to the mechanical stability of PP layer,the PP/HDPE double-layer microporous mem brane could be prepared at a higher heat-setting temperatu re than that of PE monolayer *** this work,the effects of heat-setting temperature on the pore structure and properties of PP/HDPE dou ble-layer membrane were *** the increase of heat-setting temperature from 120℃to 130℃,the length of connecting bridge crystal and crystallinity in the PE layer increase due to the melting of thin lamellae and the stability of connecting bridge structure during *** corresponding air permeability,po rosity,wetta bility of liquid electrolyte and mechanical property of the heat-set microporous membrane increase,exhibiting better electrochemical ***,when the heat-setting temperature is further increased to 140℃,higher than the melting point of PE resin,some pores are closed since the lamellae and connecting bridges melt and shrink during heat-setting,resulting in a decrease of air permeability and *** contrast,there is negligible change in the PP layer within the above heat-setting temperature *** study successfully builds the relationship between the stable pore structure and property of microporous membrane during heat-setting,which is helpful to guide the production of high-pe rformance PP/PE/PP lithium batteries separator.

关键词： PP/HDPE bilayer microporous membranes Heat-setting temperature SAXS

Robust AUC maximization for classification with pairwise confidence comparisons

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第4期18卷 73-83页

作者： Haochen shi Mingkun xie Shengjun HUANG College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China MIIT Key Laboratory of Pattern Analysis and Machine Intelligence Nanjing 211106China

Supervised learning often requires a large number of labeled examples,which has become a critical bottleneck in the case that manual annotating the class labels is *** mitigate this issue,a new framework called pairwise comparison(Pcomp)classification is proposed to allow training examples only weakly annotated with pairwise comparison,i.e.,which one of two examples is more likely to be *** previous study solves Pcomp problems by minimizing the classification error,which may lead to less robust model due to its sensitivity to class *** this paper,we propose a robust learning framework for Pcomp data along with a pairwise surrogate loss called *** provides an unbiased estimator to equivalently maximize AUC without accessing the precise class ***,we prove the consistency with respect to AUC and further provide the estimation error bound for the proposed *** studies on multiple datasets validate the effectiveness of the proposed method.

关键词： method pairwise weakly

Application of Tracer Experiments to Predict Leakage Channel-An Example of a Power Plant in Zhen’’An

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2014年第1期2卷 49-55页

作者： Ya-feng CHEN Qiang ZHANG shi-jie xie Chengdu University of Technology

Many water conservancy and hydropower projects are located in karst areas of which complicated structure would cause significant risks to water conservancy and hydropower projects, so identifying the presence or absence of pipeline leaks is one of important basic conditions for water conservancy and hydropower project. Determining the existence of leakage channels has important applications tracer diffusion of water tracer experiment, this paper is the experimental investigation of tracer leakage passage of a hydropower station in West China, determining the existence of leakage passage can be worked through experimental investigation on part of the left abutment of the hydropower predict leakage passage to.

关键词： Tracer experiment Tracer Fluorescein Spectrophotometer

Simulation and Prediction of the Fluorides Migration in a Tailing Pond Using Modflow

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2013年第3期1卷 33-39页

作者： shi-jie xie Qiang Zhang Yu-chong Qiu College of Environment and Civil Engineering Chengdu University of Technology College of Materials and Chemistry & Chemical Engineering Chengdu University of Technology

The hydrogeological generalized model of a tailing pond in Qian’an was established. Based on this model, the migration rules of the fluorides in the study area were subjected to the fully implicit difference method of Visual Modflow software(MT3DMS). The study indicates that the direction of fluorides migration is consistent with the direction of the stream flow generally, and the concentration of the fluorides decreases with the increase of the migration distance. The simulation results can provide scientific bases for the assessment and management of the underground water in the contaminated zone.

关键词： Tailing pond Fluoride Migration

Pore structure and oxygen content design of amorphous carbon toward a durable anode for potassium/sodium-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第9期6卷 184-194页

作者： Xiaodong shi Chuancong Zhou Yuxin Gao Jinlin Yang Yu xie Suyang Feng jie Zhang Jing Li Xinlong Tian Hui Zhang State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Science and EngineeringSchool of Chemistry and Chemical EngineeringHainan UniversityHaikouChina School of Materials Science and Engineering Central South UniversityChangshaChina Key Laboratory of Advanced Energy Materials Chemistry Nankai UniversityTianjinChina Hainan Center for Drug and Medical Device Evaluation and Service HaikouChina

Both sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)are considered as promising candidates in grid-level energy storage ***,the larger ionic radii of K+and Na+induce poor diffusion kinetics and cycling stability of carbon anode *** structure regulation is an ideal strategy to promote the diffusion kinetics and cyclic stability of carbon materials by facilitating electrolyte infiltration,increasing the transport channels,and alleviating the volume ***,traditional pore-forming agent-assisted methods considerably increase the difficulty of synthesis and limit practical applications of porous carbon ***,porous carbon materials(Ca-PC/Na-PC/K-PC)with different pore structures have been prepared with gluconates as the precursors,and the amorphous structure,abundant micropores,and oxygen-doping active sites endow the Ca-PC anode with excellent potassium and sodium storage *** PIBs,the capacitive contribution ratio of Ca-PC is 82%at 5.0 mV s^(-1) due to the introduction of micropores and high oxygen-doping content,while a high reversible capacity of 121.4 mAh g^(-1) can be reached at 5 A g^(-1) after 2000 *** SIBs,stable sodium storage capacity of 101.4 mAh g^(-1) can be achieved at 2 A g^(-1) after 8000 cycles with a very low decay rate of 0.65%for per *** work may provide an avenue for the application of porous carbon materials in the energy storage field.

关键词： oxygen doping pore structure porous carbon potassium-ion batteries sodium-ion batteries

De novo Synthesis of Chiral 3,4-Dihydroquinazolines via One-Pot Enantioselective Ugi-Azide/Cyclization Sequences

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第18期42卷 2140-2146页

作者： Zu-Kui xie Jun-Jun Ding Yi-Ming Ou Jun-Xiu shi Meng-Lan Shen Chuan-Zhi Yao Hua-jie Jiang jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and Applicationand Anhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefeiAnhui 230036China

Background and Originality Content,3,4-Dihydroquinazoline frameworks have frequently been encountered in natural products and bioactive *** the past decades,these key structures prompted the development of creative pharmaceuticals owing to their prominent biological properties,including trypanothione reductase(TryR)inhibitor,Hepatitis B virus(HBV)inhibitive activities,anticancer activities,etc.(Scheme 1A).[1]Notably,the chirality of the C4 atom is crucial for drug *** example,the DPC-083 is a potent reverse transcriptase inhibitor for the treatment of HIV infection but the undesired enantiomers exhibit virtually no activity.[ia]Therefore,developing synthetic methods for innovative chiral 4-substituted 3,4-dihydroquinazolines is significant and essential for drug discovery.

关键词： Anionic stereogenic-at-cobalt(ll)complex De novo synthesis post-Ugi transformation One-pot sequence Asymmetric synthesis Multicomponentreactions

Experimental investigation about the incipient velocity of spherical particles on a hemispherical bed surface

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第5期88卷 49-61页

作者： Chuannan Li jie Chen Changbo Jiang xie Li Zhiyuan Wu School of Hydraulic and Environmental Engineering Changsha University of Science & TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

The sediment particles play a huge role in shaping the bed load *** this research,240 water-tunnel experiments are carried out to investigate the incipient velocity of the observation particles in two particle *** accurately predict the incipient velocity of the observation particles,the equation is conceived by the rolling instability *** incipient velocity equations and experimental data are used to analyze the trend of dispersive pressure and the effect of arrangement position on *** find that it is appropriate to choose the coefficient of drag as 0.261 and the coefficient of lift as 0.198 for the incipient velocity equation of spherical particles on the hemispherical bed ***,the dispersive pressure is closely related to the flow state,particle size,and particle arrangement,which leads to the incipient velocity of the observation particle being at a minimum when the interference particle angle is 45°.Finally,the particle spacing and the projected area changed with the arrangements,directly affecting the incipient velocity of the observed *** analysis of four aspects for the coefficients,dispersive pressure,different particle spacing,and projected area will facilitate the prediction of particle incipient velocity,especially on hemispherical beds.

关键词： Hemispherical bed surface Observed particle Interference particle Dispersive pressure Incipient velocity

Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： Zhao shi Yan Xu Dunjian xie shiwei xie Amer M.Y.M.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

Ethanol extract of Cyathulae Radix inhibits osteoclast differentiation and bone loss

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2024年第3期22卷 212-223页

作者： shi Liying REN Liuyi LI Jinping LIU Xin LU Jingjing JIA Lujuan xie Baoping TANG Siyuan LIU Wei ZHANG jie Department of Pharmachemistry Xiangya School of Pharmaceutical SciencesCentral South UniversityChangsha 410013China Hunan Key laboratory of Diagnostic and Therapeutic Drug Research for Chronic Diseases Central South UniversityChangsha 410013China Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases Ministry of EducationGannan Medical UniversityGanzhou 341000China Xiangya Nursing School Central South UniversityChangsha 410013China The Third Xiangya Hospital Central South UniversityChangsha 410013China

Cyathulae Radix,a traditional Chinese medicine and a common vegetable,boasts a history spanning *** enhances bone density,boosts metabolism,and effectively alleviates osteoporosis-induced *** its historical use,the molecular mechanisms behind Cyathulae Radix’s impact on osteoporosis remain *** this study,we investigated the effects and mechanisms of Cyathulae Radix ethanol extract(CEE)in inhibiting osteoporosis and ***-week-old female mice underwent ovariectomy and were treated with CEE for eight ***-computed tomography(micro-CT)assessed histomorphometric parameters,bone tissue staining observed distal femur histomorphology,and three-point bending tests evaluated tibia mechanical ***-linked immunosorbent assay(ELISA)measured serum estradiol(E2),receptor activator for nuclear factor B ligand(RANKL),and osteoprotegerin(OPG)***-related markers were analyzed via Western blotting(WB)and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,CEE effects on RANKL-induced osteoclast formation and bone resorption were investigated in vitro using tartrate-resistant acid phosphatase(TRAP)staining,qRT-PCR,and WB *** with the ovariectomy(OVX)group,CEE treatment enhanced trabecular bone density,maximal load-bearing capacity,and various histomorphometric *** E2 and OPG levels significantly increased,while Receptor activator of nuclear factor-κB(RANK)decreased in the CEE *** downregulated matrix metallopeptidase 9(MMP-9),Cathepsin K(CTSK),and TRAP gene and protein *** bone marrow macrophages(BMMs),CEE reduced mature osteoclasts,bone resorption pit areas,and MMP-9,CTSK,and TRAP expression during osteoclast *** with DMSO treatment,CEE markedly inhibited RANK,TNF receptor associated factor 6(TRAF6),Proto-oncogene c-Fos(c-Fos),Nuclear factor of activated T-cells cytoplasmic 1(NFATc1)expressions,and Extracellular regula

关键词： Osteoporosis Osteoclast BMMs Cyathulae Radix RANKL ER/RANK/NFATc1 signaling pathway