检索结果-南通市图书馆

Enhancing betavoltaic nuclear battery performance with 3D P^(+)PNN^(+)multi-groove structure via carrier evolution

Nuclear Science and Techniques 2023年第12期34卷 1-16页

作者： Hou‑Jun He Yun‑Cheng Han Xiao‑Yu Wang Yu‑Min Liu Jia‑Chen Zhang lei ren Ming‑Jie Zheng Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China School of Nuclear Technology and Chemistry and Biology Hubei University of Science and TechnologyXianning 437100China

Betavoltaic nuclear batteries offer a promising alternative energy source that harnesses the power of beta particles emitted by *** satisfy the power demands of microelectromechanical systems(MEMS),3D structures have been proposed as a potential ***,this paper introduces a novel 3D^(63)Ni–SiC-based P^(+)PNN^(+)structure with a multi-groove design,avoiding the need for PN junctions on the inner surface,and thus reducing leakage current and power *** Carlo simulations were performed considering the fully coupled physical model to extend the electron–hole pair generation rate to a 3D structure,enabling the efficient design and development of betavoltaic batteries with complex 3D *** a result,the proposed model produces the significantly higher maximum output power density of 19.74μW/cm^(2) and corresponding short-circuit current,open-circuit voltage,and conversion efficiency of 8.57μA/cm^(2),2.45 V,and4.58%,respectively,compared with conventional planar *** analysis of the carrier transport and collection characteristics using the COMSOL Multiphysics code,we provide deep insights regarding power increase,and elucidate the discrepancies between the ideal and simulated performances of betavoltaic *** work offers a promising approach for the design and optimization of high-output betavoltaic nuclear batteries with a unique 3D design,and serves as a valuable reference for future device fabrication.

关键词： Betavoltaic nuclear battery High-output power density Three-dimensional structure Carrier drift–diffusion Carrier recombination Carrier collection efficiency

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

In vivo noninvasive study of diabetic peripheral neuropathy plantar morphology and mechanical properties based on ultrasound

引用

Chinese Medical Journal 2023年第22期136卷 2762-2764页

作者： Qiang Zhou Ying Li lei ren Boxin Yu Xiao Zhang Zhihui Qian Jianan Wu Ruixia Xu Jing Liu Luquan ren Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchunJilin 130025China Department of General Practice The First Hospital of Jilin UniversityChangchunJilin 130021China Editorial Department of Journal of Bionic Engineering Jilin UniversityChangchunJilin 130022China School of Medical Informatics and Engineering Xuzhou Medical UniversityXuzhouJiangsu 221004China

To the Editor:The incidence of diabetes complications increases with the increase in diabetes *** peripheral neuropathy(DPN)is one of the most common complications in diabetes *** is very harmful and is an important cause of diabetic foot and *** amputation rate of DPN patients is 10-20 times higher than that of nondiabetic *** 30 s,somewhere in the world,a patient’s lower limb or part of a lower limb will be surgically amputated due to DPN.[1]DPN seriously interferes with the physical and mental health of *** the same time,the high cost of treatment and rehabilitation care also causes huge economic pressure on ***,it is particularly important to identify,diagnose,and prevent DPN in the early or ultra-early stage.

关键词： diabetic neuropathy patients

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

可实现隐私保护的容错聚合签名方案

引用

宝鸡文理学院学报（自然科学版） 2024年第2期44卷 12-19页

作者：任蕾杜红珍尤毅晨刘珂何利平宝鸡文理学院数学与信息科学学院陕西宝鸡721013

目的为车联网中车辆与路边单元之间的通信提供高效的认证和隐私保护,使聚合签名的验证过程不因个别无效签名的存在而导致所聚合的所有签名验证失败,提高聚合签名的验证效率。方法将无证书密码体制和聚合签名算法相结合设计应用在车联... 详细信息

目的为车联网中车辆与路边单元之间的通信提供高效的认证和隐私保护,使聚合签名的验证过程不因个别无效签名的存在而导致所聚合的所有签名验证失败,提高聚合签名的验证效率。方法将无证书密码体制和聚合签名算法相结合设计应用在车联网场景下的具有容错性质的无证书聚合签名方案。方案采用实时更新的伪身份为车辆提供隐私保护。结果在随机预言机模型下将方案的安全性规约到椭圆曲线离散对数问题上,证明了签名方案满足不可伪造性。结论与同类型方案对比分析表明,本文方案有较高的效率和良好的性能。

关键词：无证书密码体制容错聚合签名车联网隐私保护

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic Stability of Passive Bipedal Walking on Rough Terrain： A Preliminary Simulation Study

引用

Journal of Bionic Engineering 2012年第4期9卷 423-433页

作者： Parsa Nassiri Afshar lei ren School of Mechanical Aerospace and Civil Engineering University of Manchester Manchester M13 9PL UK Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changehun 130022 P.R. China

A simplified 2D passive dynamic model was simulated to walk down on a rough slope surface defined by deterministic profiles to investigate how the walking stability changes with increasing surface roughness. Our results show that the passive walker can walk on rough surfaces subject to surface roughness up to approximately 0.1% of its leg length. This indicates that bipedal walkers based on passive dynamics may possess some intrinsic stability to adapt to rough terrains although the maxi- mum roughness they can tolerate is small. Orbital stability method was used to quantify the walking stability before the walker started to fall over, It was found that the average maximum Floquet multiplier increases with surface roughness in a non-linear form. Although the passive walker remained orbitally stable for all the simulation cases, the results suggest that the possibility of the bipedal model moving away from its limit cycle increases with the surface roughness if subjected to additional perturbations. The number of consecutive steps before falling was used to measure the walking stability after the passive walker started to fall over. The results show that the number of steps before falling decreases exponentially with the increase in surface roughness. When the roughness magnitude approached to 0.73% of the walker＇s leg length, it fell down to the ground as soon as it entered into the uneven terrain. It was also found that shifting the phase angle of the surface profile has apparent affect on the system stability. This is probably because point contact was used to simulate the heel strikes and the resulted variations in system states at heel strikes may have pronounced impact on the passive gaits, which have narrow basins of attraction. These results would provide insight into how the dynamic stability of passive bipedal walkers evolves with increasing surface roughness.

关键词： bipedal walking rough terrain dynamic stability human locomotion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Simulation of Rainfall-induced Xianchi Reservoir Landslide in Yunyang,Chongqing,China

引用

Acta Geologica Sinica(English Edition) 2024年第2期98卷 505-517页

作者： YAN Jinkai MA Yan LIU lei WANG Zhihui ren Tianxiang Chinese Academy of Geological Sciences Beijing 100037China Urban Construction School Beijing City UniversityBeijing 100083China

A calamitous landslide happened at 22:00 on September 1,2014 in the Yunyang area of Chongqing City,southwest China,enforcing the evacuation of 508 people and damaging 23 *** landslide volume comprised 1.44 million m^(3) of material in the source area and 0.4 million m^(3) of shoveled *** debris flow runout extended 400 m vertically and 1600 m *** Xianchi reservoir landslide event has been investigated as follows:(1)samples collected from the main body of landslide were carried out using GCTS ring shear apparatus;(2)the parameters of shear and pore water pressure have been measured;and(3)the post-failure characteristics of landslide have been analyzed using the numerical simulation *** excess pore-water pressure and erosion in the motion path are considered to be the key reasons for the long-runout motion and the scale-up of landslides,such as that at Xianchi,were caused by the heavy *** aim of this paper is to acquired numerical parameters and the basic resistance model,which is beneficial to improve simulation accuracy for hazard assessment for similar to potentially dangerous hillslopes in China and elsewhere.

关键词： geohazards landslide post-failure rapid and long runout ring shear test

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of the sloping seabed on 3D soil-spudcan interaction using a material point-finite element(MPM-FEM)model

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1436-1454页

作者： Zhengda lei Guangtian Zeng Huaihui ren Bisheng Wu Yuxin Jie State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijingChina Key Laboratory of the Hydrosphere Sciences of the Ministry of Water Resources BeijingChina Institute of Ocean Engineering Tsinghua UniversityBeijingChina Longyuan (Beijing) Wind Power Engineering Technology Co. Ltd.BeijingChina

The sloping seabed affects the bearing capacity and failure mechanism of soil,which may compromise the stability and safety of offshore structures such as jack-up *** paper employs a coupled model combining the material point method and finite element method(MPM-FEM)to analyze the impact of sloping seabeds on the three-dimensional soil-spudcan *** MPM-FEM model implements the B¯approach to solve the challenge of volumetric locking due to the incompressibility constraints imposed by yield *** is validated against the centrifuge *** effects of sloping seabeds on penetration resistance,soil flow pattern,lateral response,stress distribution,and failure mechanism are *** soil mainly undergoes overall failure when the ratio of penetration depth to spudcan diameter(i.e.D P/D)is between 0 and *** the slope angle increases,the soil on the side of lower slope is expelled further,resulting in an asymmetric stress distribution and a larger horizontal sliding force of *** D P/D increases to 0.75,the soil transitions to localized plastic flow failure,and the range of soil flow affected by the spudcan penetration *** results show that,when the slope angle increases,the lateral displacement and stress distribution on the lower slope of a sloping seabed is significantly larger than that of a horizontal seabed,impacting the spudcan and surrounding soil *** study suggests that the seabed slope significantly affects the range of soil flow and failure at shallow penetration,indicating that the slope angle should be taken into account in the design and installation of offshore jack-up rigs,particularly in areas with sloping seabeds.

关键词： Soil-spudcan interaction Centrifuge tests MPM-FEM model B—approach Sloping seabeds Offshore structures

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Resolution analysis of thermal neutron radiography based on accelerator-driven compact neutron source

引用

Nuclear Science and Techniques 2023年第5期34卷 139-151页

作者： Lian-Xin Zhang Si-Ze Chen Zao-Di Zhang Tao-Sheng Li Chuan Peng lei ren Rui Zhang Dan Xiao Yong Zhang Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

Owing to the immobility of traditional reactors and spallation neutron sources,the demand for compact thermal neutron radiography(CTNR)based on accelerator neutron sources has rapidly increased in industrial ***,thermal neutron radiography experiments based on a D-T neutron generator performed by Hefei Institutes of Physical Science indicated a significant resolution deviation between the experimental results and the values calculated using the traditional resolution *** experimental result was up to 23%lower than the calculated result,which hinders the achievement of the design goal of a compact neutron radiography system.A GEANT4 Monte Carlo code was developed to simulate the CTNR process,aiming to identify the key factors leading to resolution *** effects of a low collimation ratio and high-energy neutrons were analyzed based on the neutron beam environment of the CTNR *** results showed that the deviation was primarily caused by geometric distortion at low collimation ratios and radiation noise induced by highenergy ***,the theoretical model was modified by considering the imaging position and radiation noise *** modified theoretical model was in good agreement with the experimental results,and the maximum deviation was reduced to 4.22%.This can be useful for the high-precision design of CTNR systems.

关键词： Neutron radiography Spatial resolution Accelerator-driven neutron source Geant4 MTF ESF

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Neutronics analysis of a subcritical blanket system driven by a gas dynamic trap-based fusion neutron source for ^(99)Mo production

引用

Nuclear Science and Techniques 2023年第4期34卷 14-25页

作者： Hou-Hua Xiong Qiu-Sun Zeng Yun-Cheng Han lei ren Isaac Kwasi Baidoo Ni Chen Zheng-Kui Zeng Xiao-Yu Wang School of Nuclear Technology and Chemistry&Biology and Hubei Key Laboratory of Radiation Chemistry and Functional Materials Hubei University of Science and TechnologyXianning 437100China Institute of Nuclear Energy Safety Technology Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Nuclear Reactors Research Centre National Nuclear Research InstituteGhana Atomic Energy CommissionBox LG 80Legon-AccraGhana Teaching and Research Section of Nuclear Medicine School of Basic Medical SciencesHefei Institutes of Physical ScienceAnhui Medical UniversityHefei 230031China

Gamma-emitting radionuclide ^(99m)Tc is globally used for the diagnosis of various pathological conditions owing to its ideal single-photon emission computed tomography (SPECT) ***,the short half-life of ^(99m)Tc (T_(1/2)=6 h)makes it difficult to store or ***,the production of ^(99m)Tc is tied to its parent radionuclide ^(99)Mo (T_(1/2)=66 h).The major production paths are based on accelerators and research *** reactor process presents the potential for nuclear proliferation owing to its use of highly enriched uranium (HEU).Accelerator-based methods tend to use deuterium–tritium(D–T) neutron sources but are hindered by the high cost of tritium and its challenging *** this study,a new ^(99)Mo production design was developed based on a deuterium–deuterium (D–D) gas dynamic trap fusion neutron source (GDT-FNS) and a subcritical blanket system (SBS) assembly with a low-enriched uranium (LEU) ***-FNS can provide a relatively high-neutron intensity,which is one of the advantages of ^(99)Mo *** provide a Monte Carlo-based neutronics analysis covering the calculation of the subcritical multiplication factor (k_(s)) of the SBS,optimization design for the reflector,shielding layer,and ^(99)Mo production *** calculations,including the neutron flux and nuclear heating distributions,are also provided for an overall evaluation of the production *** results demonstrated that the SBS meets the nuclear critical safety design requirement (k_(s)<0.97) and maintained a high ^(99)Mo production *** proposed system can generate approximately 157 Ci ^(99)Mo for a stable 24 h operation with a neutron intensity of 1×10^(14) n/s,which can meet 50%of China’s demand in 2025.

关键词： Gas dynamic trap Fusion neutron source Molybdenum-99 Low-enriched uranium Subcritical blanket system

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

不同覆盖措施对旱区春小麦产量及碳效率的影响

引用

寒旱农业科学 2024年第6期3卷 515-521页

作者：王小燕逄蕾路建龙胡南南杨锦肖歆玥张正伟任磊甘肃省干旱生境作物学重点实验室甘肃兰州730070 甘肃农业大学农学院甘肃兰州730070 甘肃农业大学植物生产类实验教学中心甘肃兰州730070 甘肃农业大学水利水电工程学院甘肃兰州730070

为实现旱区春小麦种植生产环境效益和经济效益双赢,依托大田试验,研究不同覆盖措施秸秆带状覆盖、地膜覆盖、秸秆碎秆覆盖和对照露地平作对旱区春小麦产量及碳效率的影响,并对经济效益进行了评价。结果表明,与露地平作相比,地膜覆盖显... 详细信息

为实现旱区春小麦种植生产环境效益和经济效益双赢,依托大田试验,研究不同覆盖措施秸秆带状覆盖、地膜覆盖、秸秆碎秆覆盖和对照露地平作对旱区春小麦产量及碳效率的影响,并对经济效益进行了评价。结果表明,与露地平作相比,地膜覆盖显著提高了生育期春小麦干物质积累量,增幅为37.58%;秸秆带状覆盖提高了小麦开花期和收获期干物质积累量,增幅分别为32.65%和9.83%。秸秆碎秆覆盖、地膜覆盖千粒重较露地平作分别提高了15.55%、21.91%。地膜覆盖碳投入总量增幅最大,较露地平作增加1223.07 kg C/hm^(2)。秸秆碎秆覆盖较露地平作籽粒碳和植株碳产出量分别提高了38.41%和23.34%。秸秆带状覆盖提高了碳生产效率、碳经济效率、碳生态效率,增幅分别为0.58%、0.45%、0.24%。秸秆碎秆覆盖经济效益为3882.69元,较露地平作增加22.7%。综合表明,各覆盖措施均能提高春小麦产量和经济效益,其中秸秆带状覆盖显著提高了碳生产效率、碳经济效率和碳生态效率。

关键词：秸秆带状覆盖地膜覆盖秸秆碎秆覆盖产量碳效率

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Quality assessment of friction-stir-welded aluminum alloy welds via three-dimensional force signals

引用

Advances in Manufacturing 2024年第1期12卷 61-75页

作者： Ji-Hong Dong Yi-Ming Huang Jia-lei Zhu Wei Guan Xu-Kai ren Huan-Wei Yu lei Cui Beijing Institute of Petrochemical Technology Beijing102617People’s Republic of China Beijing Academy of Safety Engineering and Technology Beijing102617People’s Republic of China AVIC Manufacturing Technology Institute Beijing100024People’s Republic of China Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300350People’s Republic of China Shaoxing Special Equipment Testing Institute Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071ZhejiangPeople’s Republic of China

An online detection technology must be developed for realizing the real-time control of friction stir *** this study,the three-dimensional force exerted on a material during friction stir welding was collected synchronously and the relationship between the forces and welding quality was *** results indicated that the fluctuation period of the traverse force was equal to that of the lateral force during the stable welding *** phase difference between two horizontal forces wasπ/*** values of the horizontal forces increased with welding speed,whereas their amplitudes remained the *** proposed force model showed that the traverse and lateral forces conformed to an elliptical curve,and this result was consistent with the behavior of the measured *** variational mode decomposition was used to process the plunge *** intrinsic mode function that represented the real fluctuation in the plunge force varied at the same frequency as the spindle rotational *** tunnel defects occurred,the fluctuation period features were consistent with those obtained during normal welding,whereas the ratio parameter defined in this study increased significantly.

关键词： Friction stir welding(FSW) Three-dimensional force model Variational mode decomposition Tunnel defect

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：