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兵工学报 2018年第1期39卷 153-160页

作者：卢子兴武文博北京航空航天大学固体力学研究所北京100083

为提升蜂窝材料的动态力学性能,在旋转三角形变形构型基础上,针对不同旋转角建立了对应的蜂窝结构模型。利用这些蜂窝模型通过有限元分析软件ANSYS/LS-DYNA数值模拟了不同旋转角的蜂窝在冲击载荷作用下的面内动态压溃行为;同时考虑冲击... 详细信息

为提升蜂窝材料的动态力学性能,在旋转三角形变形构型基础上,针对不同旋转角建立了对应的蜂窝结构模型。利用这些蜂窝模型通过有限元分析软件ANSYS/LS-DYNA数值模拟了不同旋转角的蜂窝在冲击载荷作用下的面内动态压溃行为;同时考虑冲击速度的影响,研究了旋转角和冲击速度对其变形模式以及平台应力的影响规律,并对比分析了旋转三角形蜂窝的吸能特性。结果表明:旋转三角形蜂窝的变形过程一般可分为旋转变形和坍塌变形两个阶段,其应力-应变曲线具有"两段式应力平台"特征,且表现出明显的动态拉胀效应;当旋转角增大或冲击速度提高到某个临界值后,其应力-应变曲线只具有一个平台段,动态拉胀效应逐渐减弱;在不同冲击速度下,通过与相对密度相同的正六边形蜂窝相比较,旋转三角形蜂窝具有更好的能量吸收能力。

关键词：蜂窝材料拉胀蜂窝动态压溃旋转三角形模型负泊松比有限元

Major contribution to carbon neutrality by China’s geosciences and geological technologies

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China Geology 2021年第2期4卷 329-352页

作者： Yao Wang Chi-hui Guo Shu-rong Zhuang Xi-jie Chen Li-qiong Jia Ze-yu Chen zi-long Xia Zhen wu Development and Research Center of China Geological Survey Beijing 100037China China University of Geosciences(Beijing) Beijing 100083China East China Normal University Shanghai 200241China China Institute of Water Resources and Hydropower Research Beijing 100038China Nanjing University Nanjing 210000China

In the context of global climate change,geosciences provide an important geological solution to achieve the goal of carbon neutrality,China’s geosciences and geological technologies can play an important role in solving the problem of carbon *** paper discusses the main problems,opportunities,and challenges that can be solved by the participation of geosciences in carbon neutrality,as well as China’s response to *** main scientific problems involved and the geological work carried out mainly fall into three categories:(1)Carbon emission reduction technology(natural gas hydrate,geothermal,hot dry rock,nuclear energy,hydropower,wind energy,solar energy,hydrogen energy);(2)carbon sequestration technology(carbon capture and storage,underground space utilization);(3)key minerals needed to support carbon neutralization(raw materials for energy transformation,carbon reduction technology).Therefore,geosciences and geological technologies are needed:First,actively participate in the development of green energy such as natural gas,geothermal energy,hydropower,hot dry rock,and key energy minerals,and develop exploration and exploitation technologies such as geothermal energy and natural gas;the second is to do a good job in geological support for new energy site selection,carry out an in-depth study on geotechnical feasibility and mitigation measures,and form the basis of relevant economic decisions to reduce costs and prevent geological disasters;the third is to develop and coordinate relevant departments of geosciences,organize and carry out strategic research on natural resources,carry out theoretical system research on global climate change and other issues under the guidance of earth system science theory,and coordinate frontier scientific information and advanced technological tools of various *** goal of carbon neutrality provides new opportunities and challenges for geosciences *** the future,it is necessary to provide theoretical a

关键词： Carbon neutrality Carbon peaking Carbon emissions Carbon sequestration Key minerals Renewable energy Climate change Geosciences Geological technology China

Numerical and Experimental Study on Ventilation Panel Models in a Subway Passenger Compartment

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Engineering 2019年第2期5卷 329-336页

作者： Yu tao Mingzhi Yang Bosen Qian Fan wu Tiantian Wang Key Laboratory of Traffic Safety on Track Ministry of Education School of Traffic and Transportation Engineering Central South University Changsha 410075 China Joint International Research Laboratory of Key Technologies for Rail Traffic Safety Changsha 410075 China

The internal flow field study of car compartments is an important step in railroad vehicle design and optimization. The flow field profile has a significant impact on the temperature distribution and passenger comfort level. Experimental studies on flow field can yield accurate results but carry a high time and computational cost. In contrast, the numerical simulation method can yield an internal flow field profile in less time than an experimental study. This study aims to improve the computational efficiency of numerical simulation by adapting two simplified models—the porous media model and the porous jump face model—to study the internal flow field of a railroad car compartment. The results provided by both simplified models are compared with the original numerical simulation model and with experimental data. Based on the results, the porous media model has a better agreement with the original model and with the experimental results. The flow field parameters (temperature and velocity) of the porous media model have relatively small numerical errors, with a maximum numerical error of 4.7%. The difference between the numerical results of the original model and those of the porous media model is less than 1%. By replacing the original numerical simulation model with the porous media model, the flow field of subway car compartments can be calculated with a reduction of about 25% in computing resources, while maintaining good accuracy.

关键词： Numerical simulation Experiment Ventilation panel model Subway

Extrinsic equivalent circuit modeling of InP HEMTs based on full-wave electromagnetic simulation

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Chinese Physics B 2022年第4期31卷 638-646页

作者： Shi-Yu Feng Yong-Bo Su Peng Ding Jing-tao Zhou Song-Ang Peng wu-Chang Ding Zhi Jin University of Chinese Academic of Sciences Beijing 100029China High-Frequency High-Voltage Device and Integrated Circuits Center Institute of MicroelectronicsChinese Academy of SciencesBeijing 100029China

With the widespread utilization of indium-phosphide-based high-electron-mobility transistors(InP HEMTs)in the millimeter-wave(mmW)band,the distributed and high-frequency parasitic coupling behavior of the device is particularly *** present an InP HEMT extrinsic parasitic equivalent circuit,in which the conductance between the device electrodes and a new gate-drain mutual inductance term L_(mgd)are taken into account for the high-frequency magnetic field coupling between device *** on the suggested parasitic equivalent circuit,through HFSS and advanced design system(ADS)co-simulation,the equivalent circuit parameters are directly extracted in the multi-step *** HFSS simulation prediction,measurement data,and modeled frequency response are compared with each other to verify the feasibility of the extraction method and the accuracy of the equivalent *** proposed model demonstrates the distributed and radio-frequency behavior of the device and solves the problem that the equivalent circuit parameters of the conventional InP HEMTs device are limited by the device model and inaccurate at high frequencies when being extracted.

关键词： extrinsic equivalent circuit modeling InP HEMT HFSS and ADS co-simulation S-parameters

Effects of longitudinal range-gorge terrain on the eco-geographical pattern in Southwest China

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Journal of Geographical Sciences 2012年第5期22卷 825-842页

作者： PAN tao wu Shaohong HE Daming DAI Erfu LIU Yujie Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Institute of Tibetan Plateau Research CAS Beijing 100085 China Asian International Rivers Center Yunnan University Kunming 650091 China

China＇s southwestern special terrain pattern as parallel arrangement between lon- gitudinal towering mountains and deep valleys has significant effects on the differentiation of local natural environment and eco-geographical pattern in this region. The 1：50,000 Digital Elevation Model （DEM） data of Longitudinal Range-Gorge Region （LRGR）, meteorological observation data from the station establishment to 2010, hydrological observation data, Normalized Difference Vegetation Index （NDVI） and Net Primary Productivity （NPP） products of MOD13 and MOD17 as well as 1：1,000,000 vegetation type data were used. Moisture in- dices including surface atmospheric vapor content, precipitation, aridity/humidity index, sur- face runoff, and temperature indices including average temperature, annual accumulated temperature, total solar radiation were selected. Based on ANUSPLIN spline function, GIS spatial analysis, wavelet analysis and landscape pattern analysis, regional differentiation characteristics and main-control factors of hydrothermal pattern, ecosystem structure and function in this region were analyzed to reveal the effects of terrain pattern o~ regional dif- ferentiation of eco-geographical elements. The results show that： influenced by terrain pattern moisture, temperature and heat in LRGR have shown significant distribution cllaracteristics as intermittent weft differences and continuous warp extension. Longitudinal mountains and valleys not only have a north-south corridor function and diffusion effect on the transfer of major surface materials and energy, but also have east-west barrier function and blocking effect. Special topographic pattern has important influences on vegetation landscape diversity and spatiat pattern of ecosystem structure and function, which is the main-control factor on vegetation landscape diversity and spatial distribution of ecosystem. Wavelet variance analysis reflects the spatial anisotropy of environmental factors, NDVI and NPP, while wavele

关键词： Southwest China Longitudinal Range-Gorge Region (LRGR) "corridor-barrier" effect eco-geographical region spatial differentiation

Study of performance of small gamma camera consisting of crystal pixel array and position sensitive photomultiplier tube

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Nuclear Science and Techniques 2005年第4期16卷 238-243页

作者： ZHU Jie LIU Shi-tao LEI Xiao-Wen YAN Tian-Xin XU zi-Zong WANG Zhao-Min Department of Modern Physics University of Science and Technology of China Hefei 230026

The performance of gamma camera with NaI(Tl) array coupled with position sensitive photomultiplier tube (PSPMT) R2486 has been studied. The pixel size of NaI(Tl) crystal is 2mm×2mm and the overall dimension of the array is 48.2mm×48.2mm×5mm. There are 484 pixels in a 22×22 matrix. Because each pixel can produce a much focused light spot and restrict the spread of photons, position resolution of the gamma camera is mainly determined by pixel size. It is shown that crystal array pixel can reduce shrinkage effect and improve intrinsic position resolution greatly via restricting the spread of photons. Experimental results demonstrate that its position resolution and linearity are much improved comparing with the gamma camera using planar crystals coupled with PSPMT.

关键词：光电倍增器像素照相机 PSPMT 线性关系

Sampled-Data Observer Design for Space-Varying Distributed Parameter Systems

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Sampled-Data Observer Design for Space-Varying Distributed P...

Breakdown of Valence Shell Electron Pair Repulsion Theory in an H-Bond-Stabilized Linear sp-Hybridized Sulfur

第三十九届中国控制会议

作者： zi-Peng Wang Huai-Ning wu Tingwen Huang School of Electrical Engineering University of Jinan Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical EngineeringBeihang University Science Program Texas A&M University at Qatar

This paper considers the sampled-data observer design problem of space-varying distributed parameter systems（DPSs）. By utilizing a Lyapunov functional, a sampled-data observer design is developed by spatial linear matrix inequalities（SLMIs） to guarantee the exponential stability for the estimation error DPS. Furthermore, to solve SLMIs, the sampled-data observer design for space-varying DPSs is formulated as an LMI feasibility problem. Lastly, simulation results of a numerical example are provided to illustrate the effectiveness of the proposed method.

关键词： Sampled-data observer distributed parameter systems(DPSs) spatial linear matrix inequality(SLMI)

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CCS Chemistry 2021年第10期3卷 2584-2590页

作者： Jin wu Bo Jin Xiang Wang Yayun Ding Xiao-Li Wang Dandan Tang Xiaohong Li Jie Shu Dong-Sheng Li Qipu Lin Yan-Bo wu tao wu College of Chemistry Chemical Engineering and Material SciencesSoochow UniversitySuzhou 215123 The Key Laboratory of the Materials for Energy Storage and Conversion of Shanxi Province Institute of Molecular ScienceShanxi UniversityTaiyuan 030006 Testing and Analysis Centre Soochow UniversitySuzhou 215123 College of Materials and Chemical Engineering Hubei Provincial Collaborative Innovation Center for New Energy MicrogridKey Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002

Exploring the unusual orbital hybridization types of atoms and their new connection modes contributes to the development of chemical bond theory and can inspire compounds with unique molecular *** sulfur(S)atoms(or anions)with sp3 hybridization in a bent-bridging mode are commonly observed in many inorganic and organic ***,sp-hybridized S species have,thus far,been extremely rare,and the linearly bridging mode has only been“forcibly”achieved with the aid of metal–S multiple bonds and/or significant steric hindrance from the surrounding organic ligands.

关键词： sp-hybridized sulfur linear coo rdinat ion hydrogen bond indium sulfide VSEPR theory

Prevalence and Determinants of High-risk HPV Infection among 11549 Women from an Opportunistic Screening in Hubei Province

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Current Medical Science 2019年第4期39卷 622-630页

作者： Quan-fu MA Yu-lin GUO Han GAO Bin YAN Xuan DAI Meng XU Yu-jing XIONG Qiu-zi PENG Ying WANG Miao ZOU Xu-feng wu Department of Gynecologic Oncology Maternal and Child Health Hospital of Hubei ProvinceWuhan 430070China Cervical Cancer Control Center of Hubei Province Wuhan 430070China

High-risk human papillomavirus (hrHPV) infection plays an important role in the development of cervical intraepithelial neoplasia and cervical cancer.A total of 11 549 women were enrolled from the Maternal and Child Health Hospital of Hubei *** participant accepted hrHPV testing and completed a self^administered questionnaire about basic information and potential risk *** univariable and multivariable logistic regression model was used to explore the associations between variants and hrHPV *** results showed that hrHPV prevalence was 16.09% in Hubei Province,among which,hrHPV was more likely to be positive in women aged 51 years or above (OR=1.65,95% CI:1.28-2.14),and in women who had symptoms of bleeding after intercourse (OR=1.32,95% CI:1.17-1.50),had first sexual intercourse at the age of 18 years or below (OR=1.33,95% CI:1.07-1.64),had at least three male sexual partners (OR=2.50,95% CI:2.07-3.03),and who had been diagnosed with sexually transmitted infections (OR=1.50,95% CI:1.12-2.03).Married women (OR=0.66,95% CI:0.55-0.78) and women who frequently used condoms (OR=0.75,95% CI:0.67-0.84) had a relatively lower hrHPV *** study confirms that hrHPV infection was associated with age,marital status,symptoms of intercourse bleeding,history of sexually transmitted infections,and sex-related *** all,this study provides a baseline database prior to obtaining vaccinations for dynamic tracking of the changes in hrHPV prevalence.

关键词： high-risk human papillomavirus cervical cancer prevalence risk factors China