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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

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Water Science and Engineering 2024年第2期17卷 197-208页

作者： wei He Si-yuan Feng Jian Zhang Hong-wu Tang Yang Xiao Sheng Chen chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

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面压试验法及其在气缸垫开发中的应用

内燃机与配件 2024年第5期 21-24页

作者：苗文旱吴春卫张益民童小敏凌杰刘振家浙江杭垫科技有限公司浙江湖州313299

面压试验法广泛应用于气缸垫的设计、试制以及批量生产阶段,通过面压试验可以定性定量分析发动机气缸垫的密封状况,针对出现的问题如局部面压不足,密封筋断裂等予以改进,延长发动机的寿命,提高发动机的可靠性和稳定性。试验用面压纸通... 详细信息

面压试验法广泛应用于气缸垫的设计、试制以及批量生产阶段,通过面压试验可以定性定量分析发动机气缸垫的密封状况,针对出现的问题如局部面压不足,密封筋断裂等予以改进,延长发动机的寿命,提高发动机的可靠性和稳定性。试验用面压纸通常有两种,一种是可定量测量的胶片面压纸,一种是可定性判断的无碳复写纸做的面压纸。目前业内多采用无碳复写纸做的面压纸进行试验,根据颜色的浓淡进行判断,成本低廉易于操作,但不能提取数值做定量分析,所以建议只在气缸垫批产后抽检时使用:而在气缸垫研发阶段建议用定量测量面压纸,虽然成本较高,但可以提高颜色浓度的分析精度,可以在电脑上实现压力的可视化及数据分析,还可以与以往数据进行比较,对样件进行更加精密、多方面的数据分析。

关键词：面压试验面压纸密封面压

Auxiliary ball milling to prepare WS_(2)/graphene nanosheets composite for lithium-ion battery anode materials

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Tungsten 2024年第1期6卷 124-133页

作者： Yong-Lin wu Jia-Bin Hong wei-Xu Zhong chun-Xiang Wang Zhi-Feng Li Sydorov Dmytro Jiangxi Provincial Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Institute of Bioorganic Chemistry and Petrochemistry National Academy of Sciences of UkraineKiev 02160Ukraine

A novel nano-WS_(2)/graphene nanosheets(GNSs)composite is obtained by ball milling with xylitol as auxiliary agent and hightemperature *** improves the shear force during ball milling and well overcomes the van der Waals interactions between the interlayer of graphite and WS_(2).Through high-temperature calcination,GNSs and WS_(2) nanosheets can form tight interface *** produced WS_(2)/GNSs composites can be used as anode materials for lithium-ion batteries,while maintaining a high reversible specific capacity of 705 mAh·g^(-1)with the capacity retention of 95%at a current density of 250 mA·g^(-1)after 200 cycles,mainly because WS_(2)/GNSs composites have a higher Li^(+)diffusion coefficient of 2.2×10^(-9)cm^(2)·s^(-1)and a higher specific surface area of 70.10 m^(2)·g^(-1).As a result,the xylitol-assisted ball milling method designed in this work is suitable for extended preparation of peeling of two-dimensional layer materials into nanosheets.

关键词： Lithium-ion battery Anode material WS_(2) Graphene nanosheets Auxiliary ball milling

Cardo poly (ether sulfone) toughened E51/DETDA epoxy resin and its carbon fiber composites

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新型炭材料（中英文） 2024年第4期39卷 681-691页

作者： wu Rong-peng ZHANG Xing-hua wei Xing-hai JING De-qi SU wei-guo ZHANG Shou-chun Research Center of Advanced Thermoplastic Composites Engineering Institute of Coal ChemistryChinese Academy SciencesTaiyuan 030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy SciencesTaiyuan 030001China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033China

A toughener that can effectively improve the interlaminar toughness in carbon fiber composites is crucial for various *** investigated,the toughening effects of phenolphthalein-based cardo poly(ether sulfone)(PES-C)on E51/DETDA epoxy and its carbon fiber composites(CFCs).Scanning electron microscopy showed that the phase structures of PES-C/epoxy blends change from island(of dispersed phase)structures to bi-continuous structures(of the matrix)as the PES-C content increased,which is associated with reaction-induced phase *** adding 15 phr PES-C,the glass transition temperature(T_(g))of the blends increased by 51.5℃,and the flexural strength,impact strength and fracture toughness of the blends were improved by 41.1%,186.2%and 42.7%,*** improvements could be attributed to the phase separation structure of the PES-C/epoxy sys-tem.A PES-C film was used to improve the mode-II fracture toughness(G_(IIC))of *** G_(IIC) value of the 7μm PES-C film toughened laminate was improved by 80.3%compared to that of the control *** increase in G_(IIC) was attributed to cohesive failure and plastic deformation in the interleaving region.

关键词： Epoxy resin CFRP PES-C Toughness

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-wei wu Yuan-Qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia Jin Yuxue wu Feng wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Blind Signal Reception in Downlink Generalized Spatial Modulation Multiuser MIMO System Based on Minimum Output Energy

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Chinese Journal of Electronics 2024年第2期33卷 504-515页

作者： wei-Chiang wu College of Mechanical and Electrical Engineering Sanming University

This paper considers downlink multiuser multiple-input-multiple-output system with parallel spatial modulation scheme, in which base station transmitter antennas are separated into K groups corresponding to K user terminals. Generalized spatial modulation is employed, in which a subset(more than single antenna) of transmit antenna array are activated and the activating pattern corresponds to specific spatial symbol. Different from existing precoding-based algorithms, we develop a two-stage detection scheme at each user terminal: In the pre-processing stage, a minimax algorithm is proposed to identify the indices of active antennas, where the key idea is that the minimum output energy of the detector is maximized; A constrained minimum output energy algorithm is proposed in the post-processing stage to mitigate multiuser interference and extract temporal symbols. Compared with existing precoding-based algorithms, the complexity is significantly reduced. Moreover, the proposed algorithm is semi-blind,in which only a small subset of channel state information is required to identify active antennas as well as eliminate multiuser interference. Simulation results demonstrate that the proposed algorithm is near-far resistant and the spectral efficiency is extensively increased compared to the conventional spatial modulation scheme.

关键词： GSM Spectral efficiency Computer network reliability Transmitting antennas Modulation Symbols Downlink

Left atrial minimum volume by real-time three-dimensional echocardiography as an indicator of diastolic dysfunction

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Chinese Medical Journal 2013年第22期126卷 4227-4231页

作者： LIN Qiong-wen WANG wu-gang wu wei-chun WANG Hao Department of Echocardiography Fuwai Hospital Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100037 China

Background Left atrial （LA） maximum volume is becoming a prognostic biomarker for left ventricular （LV） diastolic dysfunction. However, we assessed LV diastolic function by measuring LA phasic volumes using real-time threedimensional echocardiography （RT3DE） in patients with stable coronary artery disease （CAD）. Methods Sixty-five stable CAD patients with normal LV ejection fraction （LVEF） were divided into three groups according to degree of coronary stenosis： control （n=15） with 〈50% stenosis as control group, mildS （n=25） with mild stenosis （50%- 70%） and severeS （n=25） with 〉70% stenosis. LA phasic volumes and function were evaluated and compared using RT3DE and two dimensional echocardiography （2DE）. N-terminal pro-B-type natriuretic peptide （NT-proBNP） levels were examined. The correlations of RT3DE-derived parameters with other conventional indices were analyzed. Results Significant correlations between RT3DE and 2DE for LA volume measurements were： control, r=0.93; mildS, 1=0.94; severeS, r=0.90 （all P 〈0.05）. Patients with severe coronary stenosis presented higher NT-proBNP level, indices of LA minimum volume and volume before atrial contraction, but lower LA total emptying fraction （LAEF） and LAEFpass^ve. Significant correlations of RT3DE derived LA volume indices with E/E＇（r=0.695） and NF-proBNP （r=0.630） level were found. Conclusions RT3DE derived, LA indices correlate well with NT-proBNP level and may be superior to 2DE measurements for the evaluation of LV diastolic dysfunction. Enlargement of LA minimum volume in stable CAD patients without systolic dysfunction appears earlier and may be better correlated with LV diastolic function than that of LA maximum volume.

关键词： real-time three-dimensional echocardiography left atrial volume diastolic dysfunction, coronary arterydisease, N terminal pro B type natriuretic peptide

An Asian population-based survival analysis of patients with distal esophageal and gastric cardia adenocarcinomas

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Chinese Medical Journal 2012年第22期125卷 3981-3984页

作者： ZHENG Bin ZHENG wei ZHU Yong wu wei-dong CHEN chun Fujian Med Univ Union Hosp Dept Thorac Surg Fuzhou 350001 Fujian Peoples R China

Background Gastroesophageal junction adenocarcinomas include adenocarcinomas of the distal esophagus （DE） and gastric cardia （GC）. It is controversial whether these tumors are the same entity and whether they have the same survival rates. Patients with DE and GC adenocarcinomas have a similar survival rate in the US; however, data are lacking in Asian countries. Therefore, we conducted a retrospective study to understand the implications of the tumor location in the survival of Asian patients. Methods A total of 209 patients with pathologically confirmed DE and GC adenocarcinomas, from 2005 to 2007, were included in the study. We identified patients with adenocarcinomas of the DE （DE group, n=91） and GC （GC group）（n=118）, We performed an unadjusted survival analysis using the Kaplan-Meier method, and used a Cox proportional hazards regression model to adjust for potential confounding covariates. Results We found no significant difference between the overall survival of the DE and GC groups. The 3-year survival rates were 44.8% and 53.0%, respectively, and the 5-year survival rates were 27.9% and 30.2%, respectively （P=0.162）. We found no significant difference in early staging, advanced staging, different T staging, and different N staging, between the groups. Both advanced post-operative N staging and advanced AJCC staging had a significant adverse effect on survival. Conclusions Patients with DE and GC adenocarcinomas have similar survival rates in the Asian population. Both post-operative N staging and AJCC staging are prognostic factors.

关键词： survival distal esophagus gastric cardia adenocarcinoma Asia