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半导体中相干亚毫米波的产生和传播

光学学报 1996年第4期16卷 403-407页

作者：李明孙凤国 x.c.zhang 国家自然科学基金委员会信息科学部国防科学技术大学应用物理系 RensselaerPolytechnicInstitute TroyNY12180U.S.A.

研究了超短光脉冲在GaAs表面激发相干亚毫米波振幅随入射角变化的规律，前后向辐射比值随入射角度变化的规律，实验测量了在GaAs表面镀上极薄金属薄膜后所产生的相干亚毫米波振幅对薄膜厚度的依赖关系；利用光生载流子偶极辐射的理论模... 详细信息

研究了超短光脉冲在GaAs表面激发相干亚毫米波振幅随入射角变化的规律，前后向辐射比值随入射角度变化的规律，实验测量了在GaAs表面镀上极薄金属薄膜后所产生的相干亚毫米波振幅对薄膜厚度的依赖关系；利用光生载流子偶极辐射的理论模型成功地解释了实验得到的角度依赖关系和相干亚毫米波的偏振特性。

关键词：相干亚毫米波偶极辐射半导体产生传播

Long-term observation of particle matter concentration by cAWNET in china

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Long-term observation of particle matter concentration by CA...

2019新型冠状病毒肺炎(cOVID-19)中的影像学作用

创新驱动发展提高气象灾害防御能力——第30届中国气象学会年会

作者： Y.Q.Wang x.Y.zhang J.Y.Sun x.c.zhang H.Z.che Y.Li Laboratory of Atmospheric chemistry Chinese Academy of Meteorological Sciences

The mass concentrations of PM10, PM2.5 and PM1 were investigated simultaneously in 24 stations of cAWNET (china Atmosphere Watch Network) from 2006 to 2012 using GRIMM 180 instruments. The highest PM mass were observed at the stations of Zhengzhou, xiAn and Gucheng in Hua Bei Plain (HBP) of N. china, which is the most serious hazy area of china. For example, the averaged PM10, PM2.5 and PM1 concentrations at Zhengzhou are 149.9, 94.6 and 77.7 μg m 3 , respectively. The second high PM region is in E. china, and then in S. china, with the Yangtze River Delta and the Pearl River Delta areas as their major body, respectively. According to the newest air quality standard of china with annual averaged PM10 and PM2.5 mass concentrations of 70 and 35 μg m 3 , 15 stations can meet the PM10 standard and only 7 stations (most are rural and remote stations) have concentration lower than the PM2.5 standard. Due to the large contribution of coarse mineral aerosol in N. china and more secondary aerosol formation in relative warm and humid areas of S. china, the ratios of PM2.5 to PM10 exhibit obviously increasing trend from north to south, with the highest value of 80 - 90% in the Yangtze River Delta area. In the stations near the Asian dust source, the ratios are normally less then 50%. The PM1 mass contributed most of PM2.5, accounting over 80% at the most stations. Seasonally, PM concentrations are normally highest in winter and lowest in summer at most stations, with obvious increasing in spring associated with the impact of sand and dust storm (SDS). The decreasing trend followed by increasing trend was observed at xiAn from 2006 to 2012, but the trends are not reproduceted at other stations. It indicates that there is no significant improvement or deterioration trend of air quality with PM in recent years in china.

关键词： particulate matter observation spatial and temporal variation

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国际医学放射学杂志 2020年第6期 745-745页

作者：王慧慧 W.J.Yang A.Sirajuddin x.c.zhang G.S.Liu Z.Z.Teng S.H.Zhao Department of Magnetic Resonance Imaging Fuwai HospitalNational Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College

摘要中国乃至整个世界都在经历一种新型冠状病毒的爆发,它导致感染者出现呼吸系统疾病、严重肺炎,甚至死亡。2019年12月中国武汉爆发了疫情,目前仍在蔓延。这种

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Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong Jiang Zhongwu zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(c-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)c carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

Synergistically enhanced ORR and HER performance on co-N-c coupled in-situ generated Ptco intermetallic

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Journal of Energy chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An xiao Huang Qian zhang chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material chemistry for Energy conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of co atomic sites and in-situ generated Ptco intermetallic compounds （IMcs）(o-Ptco@coNc) is proposed through co pre-anchoring and subsequent impregnation-reduction *** loading of co atoms provides a chance for in-situ generating Ptco ordered intermetallic *** remaining co single atoms and Ptco IMcs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt co IMcs and co single atoms,o-Ptco@coNc exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-Ptco@coNc delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMcs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

Revolutionizing photothermal cO_(2)hydrogenation with ceria-based catalysts

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Nano Research 2025年第1期18卷 30-49页

作者： Zhaorui zhang xiao Han Junhong zhang Yunyun Dong Jinsheng Zhao Qian xu ingqiang zhang School of chemistry and chemical Engineering Liaocheng UniversityLiaocheng 252059China Institute for catalysis Hokkaido UniversityN-21W-10Sapporo 001-0021Japan National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

In the context of achieving carbon neutrality,cO_(2)catalytic conversion technologies are effective in reducing atmospheric cO_(2)concentrations while simultaneously producing renewable *** approach is seen as a viable method for constructing a new carbon cycle,thereby effectively addressing the issue of global *** cO_(2)conversion has recently emerged as a promising research focus due to its high energy utilization efficiency,superior cO_(2)conversion,excellent product selectivity,mild operating conditions,low energy consumption and minimal operating *** oxide(ceO_(2))has been widely used in photothermal catalysis due to its unique chemical properties,particularly when used as a support material with supported metals,creating distinctive interfacial sites for catalytic *** an emerging star support in photothermal cO_(2)conversion,its contributions are equally significant and should not be ***,to our knowledge,there has been no comprehensive review of ceO_(2)applications in catalytic hydrogenation of cO_(2).In this paper,we summarize and discuss ceO_(2)-based materials for photothermal cO_(2)conversion to value-added *** research particularly focuses on the synthesis methods of ceO_(2)-supported catalysts,the history of ceO_(2)in photothermal catalysis,types of photothermal catalytic reactors,unique characterization methods for the photothermal catalysts and the photothermal cO_(2)hydrogenation reactions by ceO_(2)-based *** related to further challenges and future directions for photothermal cO_(2)hydrogenation are also provided.

关键词： cO_(2)neutrality hydrogenation photothermal catalysis ceria c1 chemistry

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1c-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei zhang Wenhao Li Yangfei chen Yang Jiang xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10c-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and x-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

co/co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang chen Yongyue Zhuang Yanxin Qiao Yu zhang Aihua Yuan Hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NcS)decorated with dual-phase co/co_(7)Fe_(3)heterojunctions(coFe@NcS).The phase composition of materials has been adjusted by controlling the alloying *** optimal coFe_(0.08)@NcS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active co_(7)Fe_(3)alloy and metallic co *** the coFe_(0.08)@NcS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/c+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

Limit of Spectral Resolution in Terahertz Time—Domain Spectroscopy

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chinese Physics Letters 2003年第8期20卷 1266-1268页

作者： Jingzhouxu TaoYuan SamuelMickan x.-c.zhang centerforTHzResearch RensselaerPolytechnicInstituteTroyNY12180USA

The pulsed nature of terahertz time-domain spectroscopy (THz-TDS) sets a fundamental limit on its spectral resolution. The spectral resolution of THz-TDS can be improved by increasing the duration of the temporal measurement, but is limited by the dynamic range of the system in the time domain. This paper presents calculations and experimental results relating the temporal dynamic range of a THz-TDS system to its spectral resolution. We discuss three typical terahertz sources in terms of their dynamic range and hence achievable spectral resolution.

关键词： Terahertz spectroscopy