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Studies on Preparation of Co-Bi Alloy Films by Electrodeposition From Nonaqueous Medium

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Chemical Research in Chinese Universities 2003年第4期19卷 499-503页

作者： LI Gao-ren TONG Ye-xiang LIU Guan-kun School of Chemistry and Chemical Engineering Zhongshan UniversityGuangzhou 510275P.R.China

Cyclic voltammetry and potentiostatic electrolysis were used to investigate the preparation of Co-Bi alloy films in a LiClO 4-DMSO system. The experimental results indicate that the Co-Bi alloy films containing 14 35%-29 77% Co can be prepared via potentionstatic electrolysis on Cu substrates, at deposition potential -1 10--1 65 V( vs. SCE) and by controlling the system composition and deposition condition. They are uniform gray films with a metallic luster and they are adhered firmly to the Cu substrate. The films were analyzed by EDS, SEM and XRD. After heat treatment of crystallization at 275 ℃ for 1 h, the alloy phase of Co-Bi can be confirmed via the XRD pattern.

关键词： Bismuth Co-Bi alloy film Electrodeposition DMSO

Flow regimes of the immiscible liquids within a rectangular microchannel

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Acta Mechanica Sinica 2021年第10期37卷 1544-1556,I0003页

作者： xiang Wang Yan Pang Yilin Ma Yanlin ren Zhaomiao Liu College of Mechanical Engineering and Applied Electronics Technology Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China Beijing Key Laboratory of Advanced Manufacturing Technology Beijing University of TechnologyBeijing100124China

Flow regimes of two immiscible liquids at the cross junction within a rectangular microchannel are experimentally *** of the flow regimes including critical conditions and interfacial deformations are *** is found that the occurrence of the tubing regime is favored by increased viscosity of the dispersed phase or reduced cross-sectional aspect ratio,leading to the shrinkage of the flow rate range that could produce *** order to reveal the physical mechanism,the force analysis is carried out based on the tunnel structure formed between the interface and channel side walls within the rectangular *** reshaping stage and pinch-off stage are mainly driven by the interfacial tension,leading to far larger neck thinning rate compared to the superficial velocity of either *** filling stage and squeezing stage are dominated by the pressure drop across the dispersed tip while the role of the shear force becomes more important with increasing tunnel *** filling period is estimated as t2≈kHwn02/Qd with k=1.34 and the squeezing period is expressed as t3/Tc=0.3Cac−*** to the force analysis,the critical tip velocity under dripping scales with three key parameters,which can be expressed as(utip/U)*~QcLtip/wtunnel3.

关键词： Cross junction Flow regime Liquid interface Force analysis Rectangular microchannel

High-throughput and simultaneous inertial separation of tumor cells and clusters from malignant effusions using spiral-contraction-expansion channels

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Microsystems & Nanoengineering 2024年第2期10卷 91-99页

作者： Zhixian Zhu Hui ren Dan Wu Zhonghua Ni Nan xiang School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical InstrumentsSoutheast University211189NanjingChina School of Mechanical Technology Wuxi Institute of TechnologyNo.1600 Gaolang West Road214129WuxiChina Department of Oncology Jiangyin People’s Hospital214400JiangyinChina

Tumor cell clusters are regarded as critical factors in cancer pathophysiology,and increasing evidence of their higher treatment resistance and metastasis compared to single tumor cells has been ***,existing cell separation methods that are designed for single tumor cells cannot be used to simultaneously purify tumor cell *** address this problem,we demonstrated a microfluidic approach for the high-throughput,continuous-flow ternary separation of single tumor cells,tumor cell clusters,and WBCs from clinical pleural or abdominal effusions by coupling slanted spiral channels and periodic contraction-expansion *** first systematically explored the influence of particle size and flow rate on particle *** separation performance indicated that 94.0%of WBCs were removed and more than 97%of MDA-MB-231 tumor cells were recovered at a high flow rate of 3500µL/***,more than 90%of tumor cell clusters were effectively preserved after ***,we successfully applied our device for the ternary separation of single tumor cells,tumor cell clusters,and WBCs from different malignant effusions collected from patients with metastatic ***,our spiral-contraction-expansion device has potential as a sample pretreatment tool for the cytological diagnosis of malignant effusions.

关键词： separation contraction removed

Impact of the thermal effect on the load-carrying capacity of a slipper pair for an aviation axial-piston pump

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Chinese Journal of Aeronautics 2018年第2期31卷 395-409页

作者： Hesheng tanG Yaobao YIN Yan ren Jiawei xiang Jun CHEN School of Mechanical Engineering WenZhou University School of Mechanical Engineering Tongji University Sany Heavy Industry Co. Ltd

A thermal hydraulic model based on the lumped parameter method is presented to analyze the load-carrying capacity of a slipper pair in an aviation axial-piston pump under specified operating conditions. Both theoretical and experimental results are presented to demonstrate the validity of the thermal hydraulic model. The results illustrate that the squeezing force and thermal wedge bearing force are the main factors that affect the film thickness and load-carrying *** high oil temperature and high load pressure, the film thickness decreases with increasing clamping force due to a combined action of the squeezing bearing force and the thermal wedge bearing force, but the load-carrying capacity will increase. An increase of the film thickness is proven to be beneficial under high shaft rotational speed but especially dangerous as it strongly increases the ripple amplitude of the film thickness, which leads to decreasing the load-carrying capacity. The structural parameters of the slipper can be optimized to achieve desired performance, such as the slipper radius ratio and orifice length diameter ratio. To satisfy the requirement of the load-carrying capacity, the slipper radius ratio should be selected from 1.4 to 1.8, and the orifice length diameter ratio should be selected from 4 to 5.

关键词： Aviation axial piston pumpFluid lubrication Load-carrying capacity Slipper pair Thermal effect

Segregation of solute atoms in ZrC grain boundaries and their effects on grain boundary strengths

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Journal of Materials Science & Technology 2022年第6期101卷 234-241页

作者： Fu-Zhi Dai Yinjie Sun Yixiao ren Huimin xiang Yanchun Zhou Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

ZrC is a promising candidate for the application in ultra-high temperature regime due to its unique combination of excellent properties,such as high melting point,good chemical inertness and high temperature *** rapid decrease of strength at high temperatures,however,is one of the obstacles that impedes its practical *** of grain boundaries by solute segregation is believed to be an effective way to improve its high temperature ***,the segregation tendency of ten solid solute atoms,including Sc,Ti,V,Cr,Y,Nb,Mo,Hf,Ta,W,in Zr C grain boundaries,and the strengthening/weakening effects on grain boundaries due to segregation are investigated by first-principles *** segregation tendency is found dominated by the size effect,which is confirmed by both a qualitative analysis and a quantitative approach based on support vector *** means that big atoms tend to segregate to grain boundary sites with local expansions,while small atoms tend to segregate to grain boundary sites with local *** on stress-strain responses indicate that segregation of small atoms(Ti,V,Cr,Nb,Ta,Mo,W)can usually improve grain boundary strengths by inducing compression strains to grain boundaries,even though there is also an *** contrast,segregation of Sc and Y will soften grain *** results reveal that strengthening of grain boundaries by solute segregation is a valuable avenue to enhance high temperature mechanical properties of ZrC,providing guidelines for further design of ZrC based materials.

关键词： ZrC Grain boundary Segregation Strength First-principles calculation Machine learning

Comparative evaluation of SPE methods for biotoxicity assessment of water and wastewater:Linkage between chemical extracting efficiency and biotoxicity outcome

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Journal of Environmental Sciences 2024年第8期142卷 33-42页

作者： Jiawei Zhou Shihao Wang Xiwei He Hongqiang ren Xu-xiang Zhang State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing 210023China

Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of ***,more chemical mixture does not necessarily translate to higher combined ***,there is a need to establish the link between chemical extracting efficiency and biotoxicity outcome to standardize extraction methods for biotoxicity assessment of environmental *** study compares the performance of five different extraction phases in solid phase extraction(SPE),namely HLB,HLB+Coconut,C18 cartridge,C18 disk and Strata-X,and evaluated their chemical extracting efficiencies and biotoxicity *** quantitatively assessed cytotoxicity,acute toxicity,genotoxicity,estrogenic activity,and neurotoxicity of the extracts using in vitro bioassays and characterized the chemical extracting efficiencies of the SPE methods through chemical recoveries of 23 model compounds with different polarities and total organic *** Pareto ranking,we identified HLB+Coconut as the optimal SPE method,which exhibited the highest level of water sample biotoxicity and recovered the most chemicals in water *** found that the biotoxicity outcomes of the extracted water samples significantly and positively correlated with the chemical extracting efficiencies of the SPE ***,we observed synchronous changing patterns in biotoxicity outcome and chemical extracting efficiencies in response to increasing sample volumes per cartridge(SVPC)during *** findings underscore that higher chemical extracting efficiency of SPE corresponds to higher biotoxicity outcome of environmental water samples,providing a scientific basis for standardization of SPE methods for adequate assessment of biotoxicities of environmental waters.

关键词： Biotoxicity Chemical recovery Solid phase extraction Surface water Wastewater

Comparison of contribution of sub-rapid cooling and shear deformation to refinement of Fe-rich phase in hypereutectic Al-Fe alloy during rheo-extrusion

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Journal of Iron and Steel Research International 2020年第11期27卷 1294-1302页

作者： xiang Wang ren-guo Guan Yuan-dong Li Ti-jun Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050GansuChina School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

A hypereutectic Al-3Fe(wt.%)alloy was subjected by rheo-extrusion,and the effect of sub-rapid cooling and shear deformation on the refinement of Fe-rich phase was *** results showed that both the primary Fe-rich phase and eutectic Fe-rich phase in the solidified Al-Fe alloy were finer than the platelike Fe-rich phase in the as-cast Al-Fe alloy with the same content of *** solidified Al-Fe alloy was subjected to three stages of shear deformation,and both the primary Fe-rich phase and eutectic Fe-rich phase were fractured and the average length was refined to 400 nm,while Fe-rich phase in the as-cast Al-3Fe(wt.%)alloy was platelike and its average length was 40 *** tensile strength and elongation of the hypereutectic Al-3Fe(wt.%)alloy containing nanosized Fe-rich phase were 162 MPa and 25.78%while those of the as-cast AI-3Fe(wt.%)alloy containing coarse platelike Fe-rich phase were 102 MPa and 16.84%,*** the refineme nt of Fe-rich phase in hypereutectic Al-Fe alloy during rheo-extrusion,the three stages of shear deformation contributed more than sub-rapid cooling.

关键词： Fe-rich phase Hypereutectic Al-Fe alloy Refinement Sub-rapid cooling Shear deformation

CD133:A cancer stem cells marker, is used in colorectal cancers

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World Journal of Gastroenterology 2013年第17期19卷 2603-2611页

作者： Fei ren Wei-Qi Sheng xiang Du Department of Pathology Shanghai Cancer Center Fudan University

Colorectal cancer is one of the most common malignant tumors worldwide. A model of cancer development involving cancer stem cells has been put forward because it provides a possible explanation of tumor hierarchy. Cancer stem cells are characterized by their proliferation, tumorigenesis, differentiation, and selfrenewal capacities, and chemoradiotherapy resistance. Due to the role of cancer stem cells in tumor initiation and treatment failure, studies of cancer stem cell markers, such as CD133, have been of great interest. CD133, a five-transmembrane glycoprotein, is widely used as a marker to identify and isolate colorectal cancer stem cells. This marker has been investigated to better understand the characteristics and functions of cancer stem cells. Moreover, it can also be used to predict tumor progression, patient survival, chemoradiotherapy resistance and other clinical parameters. In this review, we discuss the use of CD133 in the identification of colorectal cancer stem cell, which is currently controversial. Although the function of CD133 is as yet unclear, we have discussed several possible functions and associated mechanisms that may partially explain the role of CD133 in colorectal cancers. In addition, we focus on the prognostic value of CD133 in colorectal cancers. Finally, we predict that CD133 may be used as a possible target for colorectal cancer treatment.

关键词： CD133 Colorectal cancer Cancer stem cells Prognosis Chemoradiotherapy resistance

Effects of Iron on Hydrogen-producing Capacity, Hydrogenase and NADH-fd Reductase Activities of a Fermentative Hydrogen-producing Bacterial Strain B49

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High Technology Letters 2004年第4期10卷 69-74页

作者：王相晶 ren Nanqi xiang Wensheng Life Science College Northeast Agricultural University 150030 Harbin P.R.China College of Municipal & Environmental Engineering Harbin Institute of Technology 150090 Harbin P.R.China

Iron plays an important role in hydrogen production, cell growth, hydrogenase and NADH-fd reductase activities of hydrogen-producing bacterial strain B49 (AF481148 in EMBL). At the end of fermentation from 10 g/L glucose, for the culture containing 10 mg/L FeSO4*7H2O the cell growth in terms of optical density (OD) at 600nm was 1.13, the ratio of ethanol amount (mg/L) to acetate amount (mg/L) was 1.55, and the accumulated hydrogen volume was 1816.3 ml H2/L culture; whereas for the culture of 80 mg/L FeSO4*7H2O OD600nm was increased to 1.34, the accumulated hydrogen volume was increased to 2360.5 ml H2/L culture, and the ratio of ethanol amount (mg/L) to acetate amount (mg/L) decreased to 1.31. Moreover, the iron addition to the medium at different fermentation time could affect hydrogen-producing ability. However, the later the addition time of FeSO4*7H2O was postponed, the less the effect on hydrogen evolution was. In the course of fermentation, the specific activities of hydrogenase and NADH-fd reductase of hydrogen-producing bacterial strain B49 decreased with the consumption of iron.

关键词：氢化酶还原酶生物活性发酵工艺细菌 NADH-fd 能源清洁燃料生物燃料