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Tunable bandgaps and flat bands in twisted bilayer biphenylene carbon

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Chinese Physics B 2021年第7期30卷 451-455页

作者： Ya-Bin Ma Tao Ouyang Yuan-Ping Chen Yue-e Xie School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Faculty of Science Jiangsu UniversityZhenjiang 212013China

Owing to the interaction between the layers,the twisted bilayer two-dimensional(2 D)materials exhibit numerous unique optical and electronic properties different from the monolayer counterpart,and have attracted tremendous interests in current physical research *** means of first-principles and tight-binding model calculations,the electronic properties of twisted bilayer biphenylene carbon(BPC)are systematically investigated in this *** results indicate that the effect of twist will not only leads to a phase transition from semiconductor to metal,but also an adjustable band gap in BPC(0 me V to 120 me V depending on the twist angle).Moreover,unlike the twisted bilayer graphene(TBG),the flat bands in twisted BPC are no longer restricted by"magic angles",i.e.,abnormal flat bands could be appeared as well at several specific large angles in addition to the small *** charge density of these flat bands possesses different local modes,indicating that they might be derived from different stacked modes and host different *** exotic physical properties presented in this work foreshow twisted BPC a promising material for the application of terahertz and infrared photodetectors and the exploration of strong correlation.

关键词： twisted bilayer biphenylene carbon adjustable band gap flat bands

Deflection of transient thermoelastic circular plate by Marchi-Zgrablich and Laplace integral transform technique

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Theoretical & Applied Mechanics Letters 2012年第2期2卷 19-22页

作者： Badrinath e.Ghonge Kirtiwant P.Ghadle Department of Mathematics Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad-431004MaharashtraIndia

This paper deals with the determination of temperature distribution and thermal deflection function of a thin circular plate with the stated conditions. The transient heat conduction equation is solved by using Marchi-Zgrablich transform and Laplace transform simultaneously and the results of temperature distribution and thermal deflection function are obtained in terms of infinite series of Bessel function and it is solved for special case by using Mathcad 2007 software and represented graphically by using Microsoft excel 2007.

关键词： circular plate transient heat conduction thermal deflection problem Marchi-Zgrablich,Laplace integral transform

Principle and Potential of Gradient elution in Planar Chromatography

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分析测试学报 1989年第3期 6-14页

作者： Dieter e. Jaenchen CAMAG, Muttenz Switzerland

It was the intention of this paper to show some recent developments in thin layer chroma-togrphy aiming at increasing the separation efficiency by instrumental means and techniquesusing existing separation layers. Gradient elution in the normal phase is a most efficient wayto achieve this goal. Multi-dimensional separations by coupling gradient elution column liquid chromatography inthe reversed phase with AMD gradient elution in normal phase is suitable to achieve newdimensions of separation numbers. Assuming that the N numbers reported for HPLC translateinto separation numbers near 100, by coupling the two kinds of chromatography, separationnumbers around 500 become practically usable.

关键词： Gradient elution in planar caromatography Automated Multiple Development (AMD) Direct coupling of HFLC and TLC(AMD) Multi-dimensional separation

Revisiting mechanisms of resistance to immunotherapies in metastatic clear-cell renal-cell carcinoma

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Cancer Drug Resistance 2023年第2期6卷 314-326页

作者： Monica Sheila Chatwal Jad Chahoud Philippe e.Spiess Department of Genitourinary Oncology H.Lee Moffitt Cancer Center and Research InstituteTampaFL 33612USA

Renal-cell carcinoma(RCC)remains a leading cause of cancer-related mortality *** newer therapeutic combinations of immune checkpoint inhibitors and targeted therapies have greatly improved outcomes,resistance to these therapies is becoming a challenge for long-term *** of resistance have been explored in a variety of solid tumors,including *** upon our review of the current literature on the mechanisms of resistance to immunotherapies for the management of metastatic clear-cell renal cell carcinomas(mccRCC),the ensuing conclusions have been made:The management of mccRCC has progressed substantially with the.advent of checkpoint inhibitors and targeted oral therapies,alone and/or in ***,innate or developed resistance to these therapies remains an ongoing challenge,particularly to immune checkpoint inhibitors(ICIs).Several of the known mechanisms of resistance have been well defined,but recent progression in cellular therapies helps to expand the armamentarium of potential combination options that may overcome these modes of resistance and improve long-term disease control and survival for an otherwise dismal *** the ensuing review and update of the literature on the mechanisms of resistance to immunotherapies in mccRCC,we have revisited the known resistance mechanisms of immunotherapies in metastatic clear-cell RCC and explored ongoing and future strategies to overcome them.

关键词： Metastatic clear-cell renal-cell carcinoma immune therapy checkpoint inhibitor resistance chimeric antigen receptor T-cell therapy

effects of Thickness and Polarization Field on the Photovoltaic Properties of BiFeO3 Thin Films

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Chinese Physics Letters 2014年第3期31卷 144-147页

作者： ZHOU Yin-e TAN Xin-Yu YU Ben-Fang LIU Li YUAN Song-Liu JIAO Wei-Hong School of Physics Huazhong University of Science and Technology Wuhan 430074 College of Science China Three Gorges University Yichang 443002 Research Institute for New energy China Three Gorges University Yichang 443002

We study the effects of film thickness on lattice parameters, direct band gap and photovoltaic outputs in the sol-gel derived BiFeO3 thin films. With the change of the film thickness, the great transitions will take place in the preferred orientation and lattice parameters. Furthermore, the photovoltaic outputs are significantly dependent on the film thickness. The results show that the open circuit voltage gradually increases and the short circuit current reciprocally decreases with the increase of film thickness. In particular, we demonstrate for the first time that there are tunable photovoltaic outputs with external electric field polarization switching in the polycrystalline BiFeO3 film, which is critical for the future device applications based on the photovoltaic properties of BiFeO3 films.

关键词： THIN films -- Research PHOTOVOLTAIC effect ReSeARCH OPTICAL polarization THICKNeSS measurement PHYSICS research

非对称液压缸位移伺服系统的复合控制策略与试验研究

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机床与液压 2024年第3期52卷 131-135页

作者：鄂东辰董兴华蔡玉强王志军路时雨张立杰华北理工大学机械工程学院河北唐山063210 唐山工业职业技术学院河北唐山063210 燕山大学河北省重型机械流体动力传输与控制重点实验室河北秦皇岛066000

非对称液压缸的位移伺服系统存在两腔作用面积不等、系统模型不确定等特点,给液压缸高精度位移跟踪控制造成了巨大的困难。对此,提出以速度前馈为主与位移反馈为辅的复合控制策略。设计一种新的以控制电流和阀口压差为自变量的伺服阀流... 详细信息

非对称液压缸的位移伺服系统存在两腔作用面积不等、系统模型不确定等特点,给液压缸高精度位移跟踪控制造成了巨大的困难。对此,提出以速度前馈为主与位移反馈为辅的复合控制策略。设计一种新的以控制电流和阀口压差为自变量的伺服阀流量计算模型,并根据该模型设计液压测试回路,通过测试结果辨识模型中的参数。根据伺服阀流量模型与目标位移轨迹计算速度前馈控制量。基于PI控制求出位移误差反馈控制量。最后,将速度前馈和位移反馈控制量相叠加作为伺服阀的驱动电压。通过试验得出在复合控制策略下液压缸位移跟踪的最大误差与目标位移幅值之比为2.1%,相对PID控制跟踪误差明显减小。提出的控制策略为生产实际中非对称液压缸的位移跟踪控制提供了一种简单、有效的方法。

关键词：复合控制非对称液压缸流量模型位移伺服系统

Auger Depth Profiling of Carbonized SiC/Si Samples

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Journal of Materials Science & Technology 1997年第6期13卷 499-502页

作者： Shahzad Naseem and Shazia Yasin(Centre for Solid State Pliysics, University of the Punjab, Quaid-e-Azam Campus, Lahore-54590, Pakistan) Centre for Solid State Physics University of the Punjab Quaid-e-Azam Campus Lahore-54590 Pakistan Microelectronics Research Centre Cavendish Lab. University of Cambridge Madingley Road Cambridge CB3 OHE United Kingdom

Silicon carbide (SiC) has been prepared by passing natural gas over (100) oriented hot Si substrate at different temperatures in the range 930~1000℃. Reaction times of 60 and 90 min are *** profile, using Auger electron Spectroscopy, shows the formation of SiC under a thin coating of carbon for the samples prepared at 930 and 950℃. Annealing, at 1050℃ for 12 h,results in a more pronounced formation of SiC. It is found that at the temperature of 1000℃and reaction times of 60 and 90 min, a hard diamond-like coating is formed.

关键词： SiC Auger Depth Profiling of Carbonized SiC/Si Samples

effect of various drinking water on human micronucleus frequency in high-risk population of PHC

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World Journal of Gastroenterology 1998年第2期4卷 91-92页

作者： Liu e Zhang QN Li WG

ＥｆｅｃｔｏｆｖａｒｉｏｕｓｄｒｉｎｋｉｎｇｗａｔｅｒｏｎｈｕｍａｎｍｉｃｒｏｎｕｃｌｅｕｓｆｒｅｑｕｅｎｃｙｉｎｈｉｇｈｒｉｓｋｐｏｐｕｌａｔｉｏｎｏｆＰＨＣＬＩＵＥｒ，ＺＨＡＮＧＱｉＮａｎａｎｄＬＩＷｅｎ... 详细信息

ＥｆｅｃｔｏｆｖａｒｉｏｕｓｄｒｉｎｋｉｎｇｗａｔｅｒｏｎｈｕｍａｎｍｉｃｒｏｎｕｃｌｅｕｓｆｒｅｑｕｅｎｃｙｉｎｈｉｇｈｒｉｓｋｐｏｐｕｌａｔｉｏｎｏｆＰＨＣＬＩＵＥｒ，ＺＨＡＮＧＱｉＮａｎａｎｄＬＩＷｅｎＧｕａｎｇＳｕｂｊｅｃｔｈｅａｄｉ...

关键词： liver neoplasms/etiology carcinoma, hepatocellular/etiology water micronucleus tests lymphocytes risk factors

A Simulating Model of Fertility Policy and Population Trends in China

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China Population Today 1997年第6期14卷 14-15页

作者： Zhang e. Chen J. Wang A.

Chinad s population policy and family planning programme have focused their attention on.a decline of the fertility *** Wan-Xi-Shao policy(i.e..the policy ofde ferred,spaced but fewer births)practised in the 1970s had brought about a rapid decline of the fertility leve1 in the *** *** total fertility rate(TFR)of China's pop-ulation reduced from5.81 in1970 t 2.75 in *** from the late 1970s and early 1980s,the present family plan-ning policy,which encourages women of dhildbearing age to have only one *** cont ributed to a continuous decline of the fertility rate。with TFR dropped to below the replacement level from 1990 to 1995.

关键词： Model Fertility China