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Some Considerations on Energy Levels of quantum Cascade Lasers

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Chinese Physics Letters 1999年第6期16卷 443-445页

作者： yang quan-kui LI Ai-zhen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

Conduction band non-parabolicity is taken into account and a numerical method is proposed to calculate the electron subband energy levels and corresponding wave functions in the active region of quantum cascade *** a coupled double-well vertical transition mode active region,the calculated △E21=32 meV,△E32=270 meV correspond,respectively,to the energy of an optical phonon and that of a photon at wavelength λ=4.5μ*** a coupled triple-well vertical transition active region,the calculated △E21=32.4 meV,△E32=250 meV correspond to the energy of an optical phonon and the photon energy at wavelength λ=5.0μm.

关键词： phonon transition parabolic

Investigation of Hole Mobility in GaInP/(In) GaAs/GaAs p-Type Modulation Doped Heterostructures

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Chinese Physics Letters 1999年第1期16卷 50-52页

作者： yang quan-kui LI Ai-zhen CHEN Jian-xin State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

Ga_(0.51)In_(0.49)P/(In)GaAs/GaAs heterostructure is regarded as an excellent candidate for two dimensional hole gas system as it has a large valence band offset *** this paper,we report the hole mobility in GaInP/GaAs and GaInP/In_(0.20)G_(0.80)As/GaAs p-type modulation doped heterostructures grown by gas source molecular beam epitaxy with different p-channels and doping *** influences of Be:GaAs cap layer,δ-doping,and strained InGaAs p-channel on hole mobility are discussed,and qualitatively explained by the ionized impurity scattering ***,it was shown that the improvement of hole mobility could be achieved by the δ-doping method combined with strained InGaAs channel.

关键词： GaAs/Ga scattering mobility

Experimental Study of InP-Based InAlAs/InGaAs quantum Well Infrared Photodetectors Operating at the 3-5μm Wavelength Region

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Chinese Physics Letters 1999年第10期16卷 747-749页

作者： ZHANG Yong-gang LI Ai-zhen CHEN Jian-xin yang quan-kui REN Yao-cheng State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

Gas source molecular beam epitaxy grown InP-based InAlAs/InGaAs quantum well infrared photodetectors operating at 3—5 pm atmosphere window have been fabricated;their structural,electrical and optical characteristics have been *** detectors show peak response wavelength Ap at 3.85μm,with spectral width AX/Xp of 4.6%and 7.2%at 1 and 5 V bias voltages,*** low dark current of the detectors has been *** 2 V bias the dark current is below InA at 77K and remains low value of 10 nA at 150 *** background limited infrared performance temperature Tblip as high as 165 K has been measured.

关键词： InP Infrared quantum

High Current Gain In_(0.49)Ga_(0.51)P/GaAs Heterojunction Bipolar Transistors with Double Spacers Grown by Gas Source Molecular Beam Epitaxy

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Chinese Physics Letters 2000年第12期17卷 915-917页

作者： CHEN Xiao-Jie CHEN Jian-Xin CHEN Yi-Qiao PENG Peng yang quan-kui LI Ai-Zhen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

This paper reports the improved performance of the lattice-matched N-p^(+)-n In_(0.49)Ga_(0.51)P/GaAs heterojunction bipolar transistors(HBTs)with undoped spacers grown by the gas source molecular beam epitaxy.A 600ÅGaAs base doped with beryllium at 3 × 1019cm^(-3) and a 1000Å In_(0.49)Ga_(0.51)P emitter doped with silicon at 3 × 1017cm^(-3) have been *** both sides of the base,the 50Åundoped GaAs spacers were *** with emitter area of 100× 100μm^(2) were fabricated by using selective wet chemical etching *** measured results of HBTs reveal cood junction characteristics,and the common-emitter current gain reaches 320 at the collector current density of 280 A/cm^(2).

关键词： technique. emitter heterojunction

Decarbonization options of the iron and steelmaking industry based on a three-dimensional analysis

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 388-400页

作者： Xin Lu Weijian Tian Hui Li Xinjian Li kui quan Hao Bai Department of Metallurgy Graduate School of EngineeringTohoku UniversitySendai 980-8579Japan School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China China Metallurgical Industry Planning and Research Institute(MPI) Beijing 100711China Carbon Dioxide Research Division CISDI Research&Development Co.Ltd.Chongqing 401122China

Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel *** decarbonization options of China’s ironmaking and steelmaking sector were discussed based on a systematic three-dimensional low-carbon analysis from the aspects of resource utilization(Y),energy utilization(Q),and energy cleanliness which is evaluated by a process general emission factor(PGEF)on all the related processes,including the current blast furnace(BF)-basic oxygen furnace(BOF)integrated process and the specific sub-processes,as well as the electric arc furnace(EAF)process,typical direct reduction(DR)process,and smelting reduction(SR)*** study indicates that the three-dimensional aspects,particularly the energy structure,should be comprehensively considered to quantitatively evaluate the decarbonization road map based on novel technologies or *** scrap utilization(improvement of Y)and the substitution of carbon-based energy(improvement of PGEF)in particular is *** terms of process scale,promoting the development of the scrap-based EAF or DR-EAF process is highly encouraged because of their lower *** three-dimensional method is expected to extend to other processes or industries,such as the cement production and thermal electricity generation industries.

关键词： peak CO_(2)emission low carbon management decarbonization option energy-intensity industry ironmaking and steelmaking

Experimental and numerical study on protective effect of RC blast wall against air shock wave

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Defence Technology（防务技术） 2024年第1期31卷 567-579页

作者： Xin-zhe Nian quan-min Xie Xin-li Kong Ying-kang Yao kui Huang State Key Laboratory of Precision Blasting Jianghan UniversityWuhan430056China Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan430056China Hubei(Wuhan)Institute of Explosion and Blasting Technology Jianghan UniversityWuhan430056China College of Defense Engineering Army Engineering University of PLANanjing210007China Institute of Defense Engineering AMSPLALuoyang471023China

Prototype experiments were carried out on the explosion-proof performance of the RC blast *** mass of TNT detonated in the experiments is 5 kg and 20 kg *** shock wave overpressure was tested in different *** above experiments were numerically simulated,and the simulated shock wave overpressure waveforms were compared with that tested and given by CONWEP *** results show that the numerically simulated waveform is slightly different from the test waveform,but similar to CONWEP *** dimensional analysis and numerical simulation under different working conditions,the equation for the attenuation rate of the diffraction overpressure behind the blast wall was *** to the corresponding standards,the degree of casualties and the damage degree of the brick concrete building at a certain distance behind the wall can be determined when parameters are *** above results can provide a reference for the design and construction of the reinforced concrete blast wall.

关键词： Blast wall Shock wave Diffraction Overpressure Protection

A Novel Ursane Triterpene from Rubus swinhoei

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Chinese Chemical Letters 2001年第3期12卷 245-246页

作者： Wei quan ZHAO Li Sheng DING Qiang ZHANG Ming kui WANG Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041 West China University of Medical Sciences Chengdu 610041

A novel ursane triterpene, named swinhoeic acid, was isolated from the roots of Rubus swinhoei. Its structure was elucidated as 18, 19-seco, 2 alpha, 3 beta -dihydroxy-19-oxo-urs-11, 13(18)-dien-28-oic acid by means o... 详细信息

关键词： Rubus swinhoei swinhoeic acid

光稀释效应对O_(2)近红外气辉星载测风的影响

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光谱学与光谱分析 2025年第1期45卷 160-169页

作者：李昊天李发泉李娟王后茂武魁军何微微烟台大学物理与电子信息学院山东烟台264005 中国科学院精密测量科学与技术创新研究院湖北武汉430071 中国科学院西安光学精密机械研究所陕西西安710119 中国科学院国家空间科学中心北京100190

利用星载光谱成像干涉仪测量O_(2)(a^(1)Δ^(g))日辉的多普勒频移信息是目前实现全球临近空间大气风场探测的先进技术手段,观测谱线O 19 P 18(7772.030 cm^(-1))的多普勒频移,可以在40~80 km的空间区域进行高精度和高灵敏度的风速测量,... 详细信息

利用星载光谱成像干涉仪测量O_(2)(a^(1)Δ^(g))日辉的多普勒频移信息是目前实现全球临近空间大气风场探测的先进技术手段,观测谱线O 19 P 18(7772.030 cm^(-1))的多普勒频移,可以在40~80 km的空间区域进行高精度和高灵敏度的风速测量,然而其探测精度受大气散射的具体影响尚不明晰。文章旨在分析光稀释效应对临近空间大气风场探测的影响,并对其引起的测风误差进行定量评估。首先介绍了O_(2)(a^(1)Δ^(g))光谱和大气散射的光谱特性。采用最新的HITRAN光谱参数、光化学反应速率常数以及大气模型计算得到O_(2)(a^(1)Δ^(g))不同反应机制的贡献。结合光化学反应速率计算得到O_(2)(a^(1)Δ^(g))的体辐射率,并分析了太阳天顶角对体辐射率分布的影响,基于爱因斯坦系数和谱线强度分别计算得到O_(2)(a^(1)Δ^(g))在不同温度和自吸收效应条件下的光谱辐射模型,并分析了不同地理气象因素对大气散射光谱造成的影响。其次,介绍了临边观测多普勒非对称空间外差光谱仪(DASH)的测量技术原理,描述了如何去除大气散射分量以生成纯净的气辉干涉图,基于DASH仪器概念对获取干涉图像的正演过程进行了阐释。再次,针对反演问题引入了“剥洋葱算法”,在考虑自吸收效应和光稀释效应影响的情况下,消除了目标层上方大气层贡献,解决了干涉图像中目标层信息的提取问题。最后,通过误差分析得到了大气风场探测精度廓线及其随地理气象因素影响的变化规律,证明光稀释效应的存在降低了干涉图对比度并增加了测量噪声,这对临边观测权重和有效信噪比产生了不利影响。研究表明,在45~80 km的切线高度范围内,测风精度受大气散射的影响较小,其误差约为2~3 m·s^(-1);而在45 km以下,测风精度受光稀释效应的影响随海拔高度的降低而急剧增大,且受地表反照率、气溶胶和云量等因素的影响而显著升高,在同时考虑三种因素影响的情况下,其探测下限最低约为40 km。

关键词：临近空间光稀释效应测量精度大气风场光学仪器

Dissipation and Adsorption Behavior of the Insecticide Ethiprole on Various Cultivated Soils in China

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Journal of Integrative Agriculture 2014年第11期13卷 2471-2478页

作者： LIU Xin-gang DONG Feng-shou XU Jun YUAN Shan-kui ZHENG Yong-quan Key Laboratory of Integrated Pest Management in Crops Ministry of Agriculture/Institute of Plant ProtectionChinese Academy of Agricultural Sciences Institute for the Control of Agrochemicals Ministry of Agriculture

In this study, the hydrolysis of the insecticide ethiprole in buffered solutions at pH 4.0, 7.0 and 9.0, respectively, and the degradation and adsorption-desorption behaviors of ethiprole in ifve agricultural soil samples from China were investigated. The half-lives under anaerobic conditions were faster than that in the aerobic experiment. Ethiprole was relatively stable under both acidic and neutral conditions while it was readily hydrolyzed under alkaling condition. The sorption of ethiprole on ifve soils was well described by the linear and Freundlich equation and mainly governed by soil organic matter. The exothermic process of ethiprole adsorption can also be well explained by physical adsorption. A weak adsorption capacity was observed in all soils, which could readily lead to leaching problems.

关键词： ethiprole adsorption desorption hydrolysis soil dissipatio