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Effects of graphene oxides on transport and deposition behaviors of bacteria in saturated porous media

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Science China(Technological Sciences) 2019年第2期62卷 276-286页

作者： GE Zhi WU Dan HE Lei liu xianwei TONG MeiPing The Key Laboratory of Water and Sediment Sciences Ministry of Education College of Environmental Sciences and EngineeringPeking University

The effects of graphene oxides on the transport and deposition behaviors of bacteria(Gram-negative Escherichia coli and Grampositive Bacillus subtilis) in quartz sand were investigated in both NaCl and CaCl_2 solutions at pH 6.5. Both breakthrough curves and retained profiles of bacteria in the absence and presence of GO under all examined solution conditions were obtained. The results demonstrated that for both types of bacteria, the presence of GO increased the transport and decreased the deposition of bacteria at both low(10 mM) and high ionic strengths(50 mM) in NaCl solutions. However, opposite observations were achieved at different ionic strengths in CaCl_2 solutions. Particularly, GO facilitated the transport and inhibited the deposition of bacteria in 1 m M CaCl_2 solutions, while they suppressed the transport of bacteria in 2.5 m M CaCl_2 solutions. Clearly, the cell transport and deposition behaviors in porous media would be greatly influenced by the GO copresent in suspensions. Furthermore, we found that with GO copresent in suspensions, the transport and deposition behaviors of bacteria were highly associated with those of GO. The heteroaggregation of bacteria and GO also contributed to the decreased cell transport in 2.5 mM CaCl_2 solutions. This study showed that GO copresent in suspensions could act as mobile carriers for bacteria transport in porous media, leading to the alteration of cell transport and deposition behaviors.

关键词： bacteria transport graphene oxide interaction cotransport porous media

Numerical Simulation and Experiments of Hydroforming of Rectangular-section Tubular Component

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Journal of Materials Science & Technology 2003年第z1期19卷 35-37页

作者： Shijian YUAN Gang liu xianwei TIAN Z.R.WANG School of Material Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Harbin Institute of Technology Harbin 150001 China

In order to reduce high calibration pressure in hydroforming of components with too small radii, a method wasproposed to manufacture automotive hollow components with rectangular shape by relatively lower pressure. Theprocess is simulated and analyzed. It is thought that the friction force between the die surface and tube is a mainreason that high pressure is needed to form small radii. Using the method proposed in this paper, a petal-like sectionshape is first preformed so that the central zones of the four sides of the preform section do not contact with the diesides, thus the tube metal is easy to flow into the transition radii area in calibration stage. Moreover, a positive forcealong the sides is produced by the internal pressure, which is beneficial to overcome the friction force and push thematerial into the radii. Therefore, the pressure for forming the transition radii is greatly reduced and the componentswith small radii can be formed with relatively lower pressure. For the experimental case conducted in this paper, theforming pressure is reduced by about 28.6% than the estimated forming pressure.

关键词： Hydroforming, Internal high pressure forming, Hollow component, Automotive part

A wingless species of the genus Hemithyrsocera Saussure(Blattodea:Ectobiidae) from China

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Zoological Systematics 2019年第2期44卷 123-131页

作者： Sainan Zhang xianwei liu Kai Li School of Life Sciences East China Normal University Shanghai Entomological Museum Chinese Academy of Sciences

A new species, Hemithyrsocera hemiptera sp. nov., is described from Southwest China, based on its shortened tegmina, and the lack of hind wings, including the illustrations of its habitus and male genitalia. A key to the Chinese species of the genus is provided. The type material is deposited in Shanghai Entomological Museum(SEM), Chinese Academy of Sciences(CAS).

关键词： Blattellinae Hemithyrsocera cockroach new species China

Numerical simulation research on multiphase flow of aviation centrifugal pump based on OpenFOAM

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Chinese Journal of Aeronautics 2024年第4期37卷 256-275页

作者： xianwei liu Jiangfeng FU Junjie YANG Dewen YIN Zhenhua ZHOU Huacong LI College of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China Norinco Group Testing and Research Institute Huayin 714200China AECC Xi’an Engine Control Technology Co.Ltd. Xi’an 710077China AECC Guizhou Honglin Aero Engine Control Technology Co.Ltd. Guiyang 550009China

This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation ***,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate ***,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is *** research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography *** on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately *** error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.

关键词： Aero engine Fuel centrifugal pump Multiphase flow OpenFOAM Volume of fluid

Terrestrial flux in sediments from the Okinawa Trough estimated using geochemical compositional data and its response to climate changes over the past 35000 a

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Acta Oceanologica Sinica 2009年第1期28卷 47-54页

作者： MENG xianwei liu Yanguang DU Dewen SHI Xuefa Key Laboratory of Marine Sedimentology and Enviromnental Geology First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

Terrestrial supply to marginal seas is a function of interaction between land and ocean in response to climate *** flux in sediments,therefore,is potential not only to reflect the paleoceanographic evolution of sedimentary basin,but also to reveal the paleoclimatic changes in source *** from the Okinawa Trough were quantitatively partitioned into terrestrial,volcanic and biogenitic end members using constrained least-squares technique for geochemical compositional *** with the density of bulk sediments and sedimentation rate,the terrestrial flux in sediments from the Okinawa Trough since the last 35 000 a was *** on surface seawater temperature（SST） and sea level changes over the past 35 000 a,the response of terrestrial flux to the climate changes was *** is demonstrated that the terrestrial supply to the Okinawa Trough mainly derived from Chinese landmass via the Changjiang（Yangtze） River and controlled by sea level *** the post-glaciation,the terrestrial flux was the lowest in response to the highest sea level *** the last glacial maximum（LGM）,the terrestrial flux was not so high as previously expected,indicating the arid climatic condition in source region was responsible for lowering the Changjiang River＇s runoff during that *** the deglaciation,the terrestrial flux increased in response to a quick rising of the sea level,probably implicating occurrence of down-slope *** four events characterized by slight increase in terrestrial flux exactly correspond to the LGM,Heinrich events（H1,H2,H3）,respectively.

关键词： terrestrial flux sea level change constrained least-squares Heinrieh events

Imprisoned Former General Manager Working for Master's Degree

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The Journal of Human Rights 2006年第1期5卷 37-38页

作者： liu xianwei

The following is a narration before the video camera of the Henan TV Station on December 27, 2003 by a prison inmate named liu xianwei,former general manager of the Zhengzhou Sanxing Company, who is now working for a ... 详细信息

关键词： Imprisoned Former General Manager Working for Master’s Degree CASS

Renal Pelvic Carcinosarcoma: One Case Report and Literature Review

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Clinical oncology and cancer researeh 2009年第5期6卷 381-383页

作者： Chunhu Yu Zhongze liu Shijun Li xianwei Wu Yong Zhu Department of Urinary Surgery Beijing Renhe Hospital Beijing 102600 China.

IntroductionRenal pelvic carcinosarcoma (RPCS) is rare in clinic,and difficultto make preoperative *** patient diagnosed as RPCS wastreated in our hospital in August *** made it as a case report asfollows.

关键词： renal pelvis carcinosarcoma diagnosis treatment.