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AC measurements of spray-deposited CdS:In thin films

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journal of Central South University 2012年第3期19卷 829-834页

作者： S.j.Ikhmayies R.N.Ahmad-Bitar Department of Basic Sciences-Physics Faculty of Information TechnologyAl Isra University Physics Department Faculty of ScienceUniversity of Jordan

Indium doped cadmium sulfide thin films(CdS:In) were produced by the spray pyrolysis technique on glass *** measurements were used to investigate the electrical properties of the films depending on Brick-layer model for polycrystalline *** measurements were performed at room temperature in the dark and room light in the frequency range from 20 Hz to 1 MHz using coplanar indium *** data were analyzed by using Bode plots for the impedance Z and dielectric loss tanδ with frequency *** is found that the impedance has no dependence on frequency in the low frequency region but has 1/f dependence in the high frequency *** dielectric loss peak is obtained,which means the presence of a single relaxation time,and hence the films are modeled by just one RC circuit which represents the *** means that there is just one conduction mechanism that is responsible for the conduction in the bulk,due to electronic transport through the *** values of the impedance in the low frequency region and relaxation times for treated and as-deposited films were estimated.

关键词：硫化镉薄膜喷射沉积测量 AC 频率范围介电损耗弛豫时间传导机制

Selenoprotein expression is regulated at multiple levels in prostate cells

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Cell Research 2006年第12期16卷 940-948页

作者： Cheryl M Rebsch Frank j Penna Ⅲ Paul R Copeland Department of Molecular Genetics Microbiology and immunology Department of Molecular Genetics Microbiology and immunologyThe Cancer Institute of New JerseyUMDNJ-Robert Wood Johnson Medical School675 Hoes LanePiscatawayNJ 08854USA

Selenium supplementation in a population with low basal blood selenium levels has been reported to decrease theincidence of several cancers including prostate *** on the clinical findings,it is likely that the antioxidantfunction of one or more selenoproteins is responsible for the chemopreventive effect,although low molecular weightseleno-compounds have also been posited to selectively induce apoptosis in transformed *** address the effects ofselenium supplementation on selenoprotein expression in prostate cells,we have undertaken an analysis of antioxidantselenoprotein expression as well as selenium toxicity in non-tumorigenic prostate epithelial cells(RWPE-1)and prostatecancer cells(LNCaP and PC-3).Our results show that two of the glutathione peroxidase family members(GPX1 andGPX4)are highly induced by supplemental selenium in prostate cancer cells but only slightly induced in RWPE-1 *** addition,GPX1 levels are dramatically lower in PC-3 cells as compared to RWPE-1 or LNCaP ***2 proteinand mRNA,however,are only detectable in RWPE-1 *** the three selenium compounds tested(sodium selenite,sodium selenate and selenomethionine),only sodium selenite shows toxicity in a physiological range of *** and in contrast to previous studies,RWPE-1 cells were significantly more sensitive to selenitethan either of the prostate cancer cell *** results demonstrate that selenoproteins and selenium metabolism areregulated at multiple levels in prostate cells.

关键词： prostate selenium selenoproteins glutathione peroxidase selenocysteine

Tapered Suction Caissons:A Numerical Investigation into Their Pull-out Performance

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China Ocean Engineering 2009年第4期23卷 695-707页

作者： M.Zeinoddini j.Keyvani M.Nabipour Faculty of Civil Engineering KNToosi University of Technology Faculty of Engineering Tarbiat Moallem University

Suction caissons have been widely used as anchors and foundations for floating and fixed offshore platforms. The pull-out performance of conventional suction caissons （with upright walls） has been investigated by a number of researchers. However, no attention has been paid to tapered suction caissons. This paper deals with the performance of tapered suction caissons under vertical pull-out loads. A numerical approach is used for this purpose. The numerical model is first verified against test data available for common upright caissons. The verified model is then used to study the pullout performance of tapered suction caissons. It is noticed that the pull-out capacities exhibited by tapered suction caissons are in general considerably higher than those from their corresponding traditional upright caissons. To obtain an insight into this superior behaviour, effects from certain soil/caisson/drainage parameters on the pull-out capacity of tapered suction caissons are studied. Soil cohesion is noticed to have a linear improving effect on the capacity of both upright and ta- pered suction caissons. The soil internal friction angle is noticed to have an exponential increasing effect on the pull-out capacity. With a constant caisson diameter, an increase in the aspect ratio is seen to particularly influence the pull-out capacity. With a constant caisson length, an increase in the aspect ratio is discovered to result in non-linear decrease in the pull-out capacity. Under undrained conditions, tapered models generally show less sensitivity to above mentioned soil/caisson parameters as compared with those under drained conditions.

关键词： suction caisson pull-out capacity numerical study upright caisson tapered caisson offshore structure sand clay drained undrained

Optimal coordinated voltage control of power systems

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第2期7卷 257-262页

作者：李艳君 HILL David j 吴铁军 Institute of Intelligent Systems and Decision Making Zhejiang University Hangzhou 310027 China Department of Electronic Engineering City University of Hong Kong Hong Kong China

An immune algorithm solution is proposed in this paper to deal with the problem of optimal coordination of local physically based controllers in order to preserve or retain mid and long term voltage stability. This problem is in fact a global coordination control problem which involves not only sequencing and timing different control devices but also tuning the pa- rameters of controllers. A multi-stage coordinated control scheme is presented, aiming at retaining good voltage levels with minimal control efforts and costs after severe disturbances in power systems. A self-pattern-recognized vaccination procedure is developed to transfer effective heuristic information into the new generation of solution candidates to speed up the convergence of the search procedure to global optima. An example of four bus power system case study is investigated to show the effectiveness and efficiency of the proposed algorithm, compared with several existing approaches such as differential dynamic programming and tree-search.

关键词：电力系统整体最佳化电压控制免疫算法

The global mismatch between equitable carbon dioxide removal liability and capacity

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National Science Review 2023年第12期10卷 111-123页

作者： Pu Yang Zhifu Mi Yi-Ming Wei Steef V.Hanssen Lan-Cui Liu D'Maris Coffman Xinlu Sun Hua Liao Yun-Fei Yao jia-Ning Kang Peng-Tao Wang Steven j.Davis The Bartlett School of Sustainable Construction University College London Energy and Power Group University of Oxford Exeter Sustainable Finance Centre University of Exeter Center for Energy and Environmental Policy Research Beijing Institute of Technology School of Management and Economics Beijing Institute of Technology Department of Environmental Science Faculty of Science Radboud University Business School Beijing Normal University Strategy Plan Department Sinopec Research Institute of Petroleum Engineering Department of Earth System Science University of California

Limiting climate change to 1.5℃ and achieving net-zero emissions would entail substantial carbon dioxide removal(CDR) from the atmosphere by the mid-century,but how much CDR is needed at country level over time is *** purpose of this paper is to provide a detailed description of when and how much CDR is required at country level in order to achieve 1.5℃ and how much CDR countries can carry out *** allocate global CDR pathways among 170 countries according to 6 equity principles and assess these allocations with respect to countries’ biophysical and geophysical capacity to deploy *** global CDR to countries based on these principles suggests that CDR will,on average,represent～4% of nations’ total emissions in 2030,rising to ～17% in ***,equitable allocations of CDR,in many cases,exceed implied land and carbon storage *** estimate～15 % of countries(25)would have insufficient land to contribute an equitable share of global CDR,and ～40% of countries(71)would have insufficient geological storage *** more diverse CDR technologies are developed,the mismatch between CDR liabilities and land-based CDR capacities will lead to global demand for six GtCO2carbon credits from 2020 to *** demonstrates an imperative demand for international carbon trading of CDR.

关键词： carbon dioxide removal land-based solutions international equity

Continued Fraction Cartesian to Geodetic Coordinate Transformation

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Computer Modeling in Engineering & Sciences 2016年第3期111卷 257-268页

作者： j.D.Turner A.Alnaqeb A.Bani Younes Khalifa University Abu DhabiUAE

A singularity-free perturbation solution is presented for inverting the Cartesian to Geodetic *** approaches for inverting the transformation use the natural ellipsoidal coordinates,this work explores the use of the satellite ground-track vector as the differential correction *** geodetic latitude is recovered by well-known elementary means.A high-accuracy highperformance 3D vector-valued continued fraction iteration is *** convergence is achieved because the starting guess for the ground-track vector provides a maximum error of 30 m for the satellite height above the Earth’s surface,throughout the LEO-GEO range of *** a result,a single iteration of the continued fraction iteration yields a maximum error for the satellite height of 10??11 *** maximum error for the geodetic anomaly of 10??9 *** coordinate transformation is completed by non-iteratively recovering the satellite height and the geodetic *** Taylor expansions are introduced and no jacobian sensitivity calculations are *** all practical applications the new algorithm provides a closed-form *** accuracy and algorithmic performance of the proposed approach is compared with other state of the art algorithms.

关键词： Geodetic transformation continued fraction singularity-free

Natural Killer Cells:Biology and Clinical Use in Cancer Therapy

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Cellular & Molecular Immunology 2004年第1期1卷 12-21页

作者： William H.D.Hallett William j.Murphy Department of Microbiology and Immunology University of Nevada School of Medicine.University of Nevada.Reno.Reno.NV.USA.

Natural killer (NK) cells have the ability to mediate both bone marrow rejection and promote engraftment,as well as the ability to elicit potent anti-tumor *** the clinical results for these processes are still *** understanding of NK cell biology,from activating and inhibitory receptor functions to the role of NK cells in allogeneic transplantation,needs to be appreciated in order to draw out the clinical potential of NK *** of bone marrow cell (BMC) rejection are known to be dependant on inhibitory receptors specific for major histocompatibility complex (MHC) molecules and on activating receptors that have many potential *** modulation of activating and inhibitory receptors may hold the key to clinical success involving NK ***-clinical studies in mice have shown that different combinations of activating and inhibitory receptors on NK cells can reduce graft-versus-host disease (GVHD),promote engraftment,and provide superior graft-versus-tumor (GVT) *** clinical data have shown that the use of KIR-ligand incompatibility produces tremendous graft-versus-leukemia effect in patients with acute myeloid leukemia at high risk of *** review will attempt to be a synthesis of current knowledge concerning NK cells,their involvement in BMT,and their use as an immunotherapy for cancer and other hematologic *** & Molecular Immunology.2004;1(1):12-21.

关键词： NK cell BMT GVHD GVT

Growth of Tellurium Nanobelts on h-BN for p-type Transistors with Ultrahigh Hole Mobility

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Nano-Micro Letters 2022年第7期14卷 43-54页

作者： Peng Yang jiajia Zha Guoyun Gao Long Zheng Haoxin Huang Yunpeng Xia Songcen Xu Tengfei Xiong Zhuomin Zhang Zhengbao Yang Ye Chen Dong-Keun Ki juin j.Liou Wugang Liao Chaoliang Tan College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Department of Electrical Engineering City University of Hong KongHong Kong SARPeople’s Republic of China Department of Physics The University of Hong KongPokfulam RoadHong Kong SARPeople’s Republic of China Department of Chemistry The Chinese University of Hong KongHong Kong SARPeople’s Republic of China Department of Chemistry City University of Hong KongHong Kong SARPeople’s Republic of China Department of Mechanical Engineering City University of Hong KongHong Kong SARPeople’s Republic of China Center of Super-Diamond and Advanced Films(COSDAF) City University of Hong KongHong Kong SARPeople’s Republic of China

The lack of stable p-type van der Waals(vdW)semiconductors with high hole mobility severely impedes the step of low-dimensional materials entering the industrial *** p-type black phosphorus(bP)and tellurium(Te)have shown promising hole mobilities,the instability under ambient conditions of bP and relatively low hole mobility of Te remain as daunting *** we report the growth of high-quality Te nanobelts on atomically flat hexagonal boron nitride(h-BN)for high-performance p-type field-effect transistors(FETs).Importantly,the Te-based FET exhibits an ultrahigh hole mobility up to 1370 cm^(2) V^(−1) s^(−1) at room temperature,that may lay the foundation for the future high-performance p-type 2D FET and metal-oxide-semiconductor(p-MOS)*** vdW h-BN dielectric substrate not only provides an ultra-flat surface without dangling bonds for growth of high-quality Te nanobelts,but also reduces the scattering centers at the interface between the channel material and the dielectric layer,thus resulting in the ultrahigh hole mobility.

关键词： Chemical vapor deposition Substrate engineering Tellurium Field-effect transistors Hole mobility

Purification of L-asparaginase II by crystallization

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 37-42页

作者： Y. LIU M. PIETZSCH j. ULRICH Thermal Process Engineering Center for Engineering Science Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany Department of Downstream Processing Institute of Pharmacy Faculty of Natural Sciences I Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

Here a case study ofL-asparaginase II out of a recombinant Escherichia coli is presented. The target protein was obtained by simple cell disintegration and acetone precipitation. The L-asparaginase II has been crystallized in three different forms in the following microbatch crystallization. The rod-shaped crystals （-400 μm edge length） were obtained at either 8℃ or 22℃ after 17h by addition of PEG6ooo. The rectangular-shaped crystals were obtained after further recrystallization of the rod-shaped crystals. The rhombic-shaped crystals formed at 8℃ after 12 days when cold ethanol was used instead of PEG6000. All crystallizations were performed in tris-acetate buffer （50mmol-L-1, pH 5.1）. By crystallization, the specific activity of L-asparaginase II has increased 5-fold. The protein content and the purity of the crystals were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE）. The more concentrated L- asparaginase II out of an extract mixture and the presence of only less minor proteins after crystallization demonstrates that crystallization is an effective and mild method to purify the target protein. The single crystal X-ray diffraction pattern reveals that the crystals are proteins and the X-ray powder diffraction （XRPD） pattern shows clearly that the crystals forming in PEG600o and ethanol have different crystal structures.

关键词： protein crystallization L-asparaginase II purification