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Terahertz generation and detection of LT-GaAs thin film photoconductive antennas excited by lasers of different wavelengths

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Chinese Physics B 2022年第2期31卷 677-680页

作者： Xin Liu qing-hao Meng Jing Ding zhi-Chen bai Jia-hui Wang Cong zhang bo Su Cun-Lin zhang Beijing Advanced Innovation Center for Imaging Theory and Technology Beijing Key Laboratory for Terahertz Spectroscopy and Imaging Key Laboratory of Terahertz Optoelectronics Ministry of EducationDepartment of PhysicsCapital Normal UniversityBeijing 100048China

A new method of generating and detecting terahertz waves is ***-temperature-grown gallium arsenide(LT-Ga As)thin films are prepared by etching a sacrificial layer(Al As)in a four-layer epitaxial structure constituted with LT-Ga As,Al As,Ga As,and semi-insulating gallium arsenide(SI-Ga As).The thin films are then transferred to clean silicon for fabricating the LT-Ga As thin film *** quality and transmission characteristics of the films are analyzed by an800-nm asynchronous ultrafast time domain spectroscopy system,and the degree of bonding between the film and silicon wafer is *** LT-Ga As thin film antennas for generating and detecting the terahertz waves are tested with a1550-nm femtosecond *** terahertz signal is successfully detected,proving the feasibility of this home-made LTGa As photoconductive *** work lays a foundation for studying the mechanism of terahertz wave generation in Ga As photoconductive antennas below the semiconductor band gap.

关键词： terahertz low-temperature-grown GaAs photoconductive antenna 1550-nm laser

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 725-732页

作者： Lei Li bo Xu Wei-Ping Tong hui zhang chun-Yan Ban Li-Zi He zhi-hao Zhao Yu-bo Zuo qing-Feng Zhu Jian-Zhong Cui Key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University School of Metallurgy and Energy Hebei United University

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid （Pb）/ liquid （Sn） diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field （〈0.3 T）. When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level （0.8-5 T）, the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.

关键词： Microstructural evolution Crystallization behavior Dendrite growth Diffusion behavior Magnetic field Solidification pattern

Association between semen collection time and semen parameters:an observational study

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Asian Journal of Andrology 2023年第3期25卷 339-344页

作者： Shun bai Xian-Chao Dou hao-Lin Qi Yan-Song Zhu Yin-Tao zhang Yi-xun Liu Xue-chun hu Cheng Cao Xian-hong Tong bo Xu Li-Min Wu Xiao-hua Jiang Reproductive and Genetic Hospital The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China School of Medical Imaging Bengbu Medical UniversityBengbu 233030China The First Clinical Medical School Anhui Medical UniversityHefei 230022China School of Life Science Anhui Medical UniversityHefei 230022China Department of Biochemistry and Molecular Biology Anhui Medical UniversityHefei 230022China Department of Urology The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China

The process of semen collection plays a key role in the quality of semen ***,the association between semen collection time and semen quality is still *** this study,ejaculates by masturbation from 746 subfertile men or healthy men who underwent semen analysis were *** median(interquartile range)semen collection time for all participants was 7.0(5.0-11.0)min,and the median time taken for semen collection was lower in healthy men than that in subfertile men(6.0 min vs 7.0 min).An increase in the time required to produce semen samples was associated with poorer semen *** those undergoing assisted reproductive technology(ART),the miscarriage rate was positively correlated with the semen collection *** adjusting for confounders,the highest quartile(Q4)of collection time was negatively associated with semen volume and sperm concentration.A longer time to produce semen samples(Q3 and Q4)was negatively correlated with progressive and total sperm *** addition,there was a significant negative linear association between the semen collection time and the sperm *** risks of asthenozoospermia(adjusted odds ratio[OR]=2.06,95%confidence interval[CI]:1.31-3.25,P=0.002)and teratozoospermia(adjusted OR=1.98,95%CI:1.10-3.55,P=0.02)were observed in Q3 than those in *** results indicate that a higher risk of abnormal semen parameter values was associated with an increase in time for semen collection,which may be related to male fertility through its association with semen quality.

关键词： asthenozoospermia semen collection time semen quality teratozoospermia

A review of reservoir damage during hydraulic fracturing of deep and ultra-deep reservoirs

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Petroleum Science 2024年第1期21卷 384-409页

作者： Kun zhang Xiong-Fei Liu Dao-Bing Wang bo Zheng Tun-hao Chen qing Wang hao bai Er-Dong Yao Fu-Jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China Tuha Downhole Operation Company CNPC Xibu Drilling Engineering Company LimitedShanshan838200XinjiangChina

Deep and ultra-deep reservoirs have gradually become the primary focus of hydrocarbon exploration as a result of a series of significant discoveries in deep hydrocarbon exploration *** reservoirs present unique challenges due to their deep burial depth(4500-8882 m),low matrix permeability,complex crustal stress conditions,high temperature and pressure(HTHP,150-200℃,105-155 MPa),coupled with high salinity of formation ***,the costs associated with their exploitation and development are exceptionally *** deep and ultra-deep reservoirs,hydraulic fracturing is commonly used to achieve high and stable *** hydraulic fracturing,a substantial volume of fluid is injected into the ***,statistical analysis reveals that the flowback rate is typically less than 30%,leaving the majority of the fluid trapped within the ***,hydraulic fracturing in deep reservoirs not only enhances the reservoir permeability by creating artificial fractures but also damages reservoirs due to the fracturing fluids *** challenging“three-high”environment of a deep reservoir,characterized by high temperature,high pressure,and high salinity,exacerbates conventional forms of damage,including water sensitivity,retention of fracturing fluids,rock creep,and proppant *** addition,specific damage mechanisms come into play,such as fracturing fluid decomposition at elevated temperatures and proppant diagenetic reactions at HTHP ***,the foremost concern in deep oil and gas development lies in effectively assessing the damage inflicted on these reservoirs by hydraulic fracturing,comprehending the underlying mechanisms,and selecting appropriate ***'s noteworthy that the majority of existing studies on reservoir damage primarily focus on conventional reservoirs,with limited attention given to deep reservoirs and a lack of systematic *** light of this,our approach entails initially summarizin

关键词： Artificial fracture Deep and ultra-deep reservoir Fracture conductivity Fracturing fluid Hydraulic fracturing Reservoir damage

Interfacial Improvement of Carbon Fiber/Epoxy Composites by Incorporating Superior and Versatile Multiscale Gradient Modulus Intermediate Layer with Rigid-flexible Hierarchical Structure

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Chinese Journal of Polymer Science 2021年第7期39卷 896-905页

作者： Pei-Feng Feng guo-Jun Song Wen-Jian zhang hao Zheng bo-Wen Li Shao-Feng Zhou Ya-qing Liu Guang-Shun Wu Li-chun Ma Institute of Polymer Materials School of Material Science and EngineeringQingdao UniversityQingdao 266071China Shanxi Province Key Laboratory of Functional Nanocomposites North University of ChinaTaiyuan 030000China School of Chemistry and Materials Science Ludong UniversityYantai264025China

In order to enhance the interfacial adhesion of carbon fiber(CF)and polymer matrix,a multiscale gradient modulus intermediate layer with rigid-flexible(GO-PA)hierarchical structure was designed and fabricated between CFs and matrix by a facile and businesslike *** polarity,roughness and wettability of CFs surface as well as the thickness of intermediate layer in composite have been significantly increased after rigid-flexible hierarchical structure was *** IFSS,ILSS,compression and impact toughness manifested that the hierarchical structure could bring about a fantastic improvement(76.8%,46.4%,40.7%and 37.8%)for the interfacial and mechanical properties than other previous ***,the establishment of CF surface with gradient modulus rigid-flexible hierarchical structure via regulation of nanoparticles and polymer array would open a new,viable and promising route to obtaining high-performance composites.

关键词： Carbon fibers Polymer-matrix composites Interface Hierarchical structure Gradient modulus

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酸性矿山废水区域沉积物中嗜酸菌多样性研究

环境科学 2006年第11期27卷 2255-2260页

作者：郝春博张洪勋白志辉张保国张徐祥中国科学院生态环境研究中心环境生物技术室北京100085 南京大学环境学院污染控制与资源化研究国家重点实验室南京210093

采集了酸性矿山废水区域酸性沉积物样品,运用16S rDNA克隆文库技术和变性梯度凝胶电泳(DGGE)技术,研究了沉积物中的嗜酸菌类群以及它们的群落结构.结果表明,沉积物中的嗜酸菌类型较新,大多数16S rDNA序列与已知序列的相似性均在97%以下... 详细信息

采集了酸性矿山废水区域酸性沉积物样品,运用16S rDNA克隆文库技术和变性梯度凝胶电泳(DGGE)技术,研究了沉积物中的嗜酸菌类群以及它们的群落结构.结果表明,沉积物中的嗜酸菌类型较新,大多数16S rDNA序列与已知序列的相似性均在97%以下.这些嗜酸菌主要为Acidobacteria,β/-γProteobacteria,-δProteobacteria,Nitrospira,Candidate Division TM7,low G+C Gram-positive类微生物.在这一酸性生态系统中,-δProteobacteria类细菌占据主导地位.对酸性沉积物中嗜酸菌多样性的研究有利于发现高效处理酸性矿山废水的方法.

关键词：酸性矿山废水沉积物嗜酸菌 16S rDNA 变性梯度凝胶电泳

Characterization of Avian Influenza A(H7N9) Virus Prevalence in humans and Poultry in huai′an,China：Molecular Epidemiology,Phylogenetic,and Dynamics Analyses

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Biomedical and Environmental Sciences 2016年第10期29卷 742-753页

作者： YANG Peng Fei YAN qing Li LIU chun Cheng XING Ya Dong zhang Min hui GAO Qiang YU hao YAO Hai bo HE Nan Jiang huai'an Center for Disease Control and Prevention Huai'an 223001 Jiangsu China hongzhe County Disease Control and Prevention Huai'an 223199 Jiangsu China

Objective To trace the source of human H7N9 cases in huai＇an and elucidate the genetic characterization of huai＇an strains associated with both humans and birds in live poultry *** An enhanced surveillance was implemented when the first human H7N9 case was confirmed in huai＇*** specimens,cloacal swabs,and fecal samples were collected and screened by real-time reverse transcription-polymerase chain reaction（RT-PCR） for H7N9 *** positive samples were subjected to further RT-PCR and genome *** phylodynamic patterns of H7N9 virus within and separated from huai＇an and evolutionary dynamics of the virus were *** Six patients with H7N9 infection were previously exposed to live poultry market and presented symptoms such as fever（〉38.0 °C） and *** of this study support the hypothesis that live poultry markets were the source of human H7N9 *** analysis revealed that all novel H7N9 viruses,including huai＇an strains,could be classified into two distinct clades,A and ***,the diversified H7N9 virus circulated in live poultry markets in huai＇***,the common ancestors of the huai＇an H7N9 virus existed in January *** mean nucleotide substitution rates for each gene segment of the H7N9 virus were（3.09-7.26）×10-3 substitutions/site per year（95% HPD：1.72×10-3 to 1.16×10-2）.Conclusion Overall,the source of exposure of human H7N9 cases in huai＇an was live poultry market,and our study highlights the presence of divergent genetic lineage of H7N9 virus in both humans and poultry specimens in huai＇an.

关键词： Molecular epidemiology H7N9 Virus Phylogenetic tree Phylodynamic analysis

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui Fan Chang‑qing Feng Rong zhang Xiao‑Yang Sun Qi An hao‑Fan bai Jiang‑bo bai Jie bao Ping Cao Qi‑Ping Chen Yong‑hao Chen Zeng‑Qi Cui An‑Chuan Fan Fan‑Zhen Feng Min‑hao Gu Chang‑Cai Han Zi‑Jie Han guo‑Zhu He Yong‑Cheng He Yang hong Yi‑Wei hu Han‑Xiong huang Wei Jiang zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑Yuan Luan Jie Ren zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑hui Song Kang Sun zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng Wang Peng‑Cheng Wang Zhao‑hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu guo‑hui zhang Hang‑Chang zhang Lin‑hao zhang Qi‑Wei zhang Xian‑Peng zhang Yu‑Liang zhang Yue zhang zhi‑Yong zhang zhi‑hao Zhou Ke‑Jun Zhu Chong Zou Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(Nanjing)Research Institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China China Academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest Institute of Nuclear Technology Xi’an 710024China University of Chinese Academy of Sciences Beijing 100049China China Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the China Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

Study of the response of 10B-doped MCP to wide-energy range neutrons from eV to MeV

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Nuclear Science and Techniques 2024年第8期35卷 132-141页

作者： Qiang Li Li‑Jiao Wang Xiang‑Biao Qiu Jing‑Wen Li Wei Xu Tao Li Ze‑Bin Lin Chang‑Jun Ning Yong‑hao Chen Rui‑Rui Fan Kang Sun Jing‑Yu Tang Rong zhang Han‑Tao Jing bo Mei Qi An hao‑Fan bai Jiang‑bo bai Jie bao Ping Cao Qi‑Ping Chen Zhen Chen Zeng‑Qi Cui An‑Chuan Fan Chang‑qing Feng Fan‑Zhen Feng Ke‑qing Gao Min‑hao Gu Chang‑Cai Han Zi‑Jie Han guo‑Zhu He Yong‑Cheng He Yang hong Yi‑Wei hu Han‑Xiong huang Wei‑hua Jia hao‑Yu Jiang Wei Jiang zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang bo Li Chao Li Gong Li Jia‑Wen Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Guang‑Yuan Luan Bin‑Bin Qi Jie Ren zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑hui Song zhi‑Xin Tan Sheng‑Da Tang Peng‑Cheng Wang Zhao‑hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Li‑Kun Xie Yi‑Wei Yang Han Yi Yong‑Ji Yu guo‑hui zhang Lin‑hao zhang Mo‑Han zhang Qi‑Wei zhang Xian‑Peng zhang Yu‑Liang zhang Yue zhang zhi‑Yong zhang Mao‑Yuan Zhao Lu‑Ping Zhou zhi‑hao Zhou Ke‑Jun Zhu Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China North Night Vision Science&Technology(Nanjing)Research Institute Co.Ltd. Nanjing 211106China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China USTC Archaeometry Lab University of Science and Technology of ChinaHefei 230026China Northwest Institute of Nuclear Technology Xi’an 710024China University of Chinese Academy of Sciences Beijing 100049China

Neutron-sensitive microchannel plates(nMCPs)have applications in neutron detection,including energy spectrum measurements,neutron-induced cross sections,and neutron imaging.10B-doped MCPs(B-MCPs)have attracted significant attention owing to their potential for exhibiting a high neutron detection efficiency over a large neutron energy *** spatial and temporal resolutions are useful for neutron energy-resolved ***,their practical applications still face many technical *** this study,a B-MCP with 10 mol%10B was tested for its response to wide-energy neutrons from eV to MeV at the Back-n white neutron source at the China Spallation Neutron *** neutron detection efficiency was calibrated at 1 eV,which is approximately 300 times that of an ordinary MCP and indicates the success of 10 B *** factors that caused the reduction in the detection efficiency were simulated and *** neutron energy spectrum obtained using B-MCP was compared with that obtained by other measurement methods,and showed very good consistency for neutron energies below tens of *** response is more complicated at higher neutron energy,at which point the elastic and nonelastic reactions of all nuclides of B-MCP gradually become *** is beneficial for the detection of neutrons,as it compensates for the detection efficiency of B-MCP for high-energy neutrons.

关键词： Neutron radiation image 10B-doped MCP Neutron response Wide-energy range neutrons