检索结果-南通市图书馆

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

闪烁体探测器中光的衰减通式（英文）

原子核物理评论 2019年第1期36卷 78-84页

作者：蓝江山赵凤仪丁萌韩成栋张亚鹏陈旭荣中国科学院近代物理研究所兰州730000 中国科学院大学核科学与技术学院北京100049

闪烁体探测器被广泛应用于当今粒子物理与原子核物理实验中。研究闪烁探测器的光衰减规律(LASD)对时间和能量的准确测量都十分重要,这一点对条形闪烁探测器尤为如此。本文以圆柱闪烁探测器为例,对各向同性的闪烁光进行立体角积分,进而... 详细信息

闪烁体探测器被广泛应用于当今粒子物理与原子核物理实验中。研究闪烁探测器的光衰减规律(LASD)对时间和能量的准确测量都十分重要,这一点对条形闪烁探测器尤为如此。本文以圆柱闪烁探测器为例,对各向同性的闪烁光进行立体角积分,进而研究不同立体角下光程差异对结果的影响。在数值计算的基础上,导出了描述LASD的通用公式。在一定条件下,公式可以约化为双指数衰减形式。对于DAMPE上PSD的实验数据,该公式能使闪烁体远端的拟合偏差从大约10%降低至2%以下。同时,模型也能够很好地描述Kaiser实验、Gierlik实验和Platino实验的实验数据。

关键词：闪烁探测器光衰减

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi Jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： chen Jinyou HU Wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

Miyaoka-type inequalities for terminal threefolds with nef anti-canonical divisors

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2025年第1期68卷 1-18页

作者： Masataka Iwai chen Jiang Haidong Liu Department of Mathematics Graduate School of ScienceOsaka University Shanghai Center for Mathematical Sciences & School of Mathematical Sciences Fudan University Department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X） · c2（X）≠0,then c1（X） · c2（X） ≥ 1/252;if further X is not rationally connected,then c1（X） · c2（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dim X-2· c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei Zhou Siwei Wang Yong chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

关键词：

Analysis of Micromechanical Properties at the Interface of Pre-wet SBS Modified Asphalt Mixture Based on Molecular Simulation Technology

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 103-113页

作者： chen Wuxing chen Shuang YU Yan ZHANG Jiangyi XU Haiyang GUO Wei School of Mines China University of Mining and TechnologyXuzhou 221000China College of Construction Engineering Jilin Uni-versityChangchun 130026China

The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and *** effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics *** diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are *** simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are *** concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more *** to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after *** to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.

关键词： pre-wet oil-stone interface interface interaction interface mechanics molecular dynamics simulation

卵巢巧克力囊肿患者应用超声介入与腹腔镜治疗临床效果对比

在线全文

学校读者我要写书评

暂无评论

中外医学研究 2023年第3期21卷 33-36页

作者：张娟杨云玲陈旭蓉朱文波荆门市康复医院湖北荆门448000

目的:对比卵巢巧克力囊肿患者应用超声介入与腹腔镜治疗的临床效果。方法:选择荆门市康复医院2019年2月—2021年2月收治的100例患者卵巢巧克力囊肿患者,按照电脑随机法分为观察组和对照组,各50例。观察组实施超声介入治疗,对照组实施腹... 详细信息

目的:对比卵巢巧克力囊肿患者应用超声介入与腹腔镜治疗的临床效果。方法:选择荆门市康复医院2019年2月—2021年2月收治的100例患者卵巢巧克力囊肿患者,按照电脑随机法分为观察组和对照组,各50例。观察组实施超声介入治疗,对照组实施腹腔镜治疗,比较和分析两组的各项手术指标、治疗效果、卵巢储备功能、并发症发生率及囊肿复发率。结果:观察组术中出血量、住院费用少于对照组,手术时间、住院时间短于对照组,差异均有统计学意义(P0.05)。治疗后观察组的卵巢储备功能指标均优于对照组(P0.05)。结论:超声介入与腹腔镜治疗均具有一定效果,但前者不会对患者卵巢储备功能造成影响,且安全性高,值得研究和推广。

关键词：卵巢巧克力囊肿超声介入腹腔镜治疗临床效果

维普期刊数据库博看期刊

Crustal magma oxidation state and endowments in porphyry copper deposits

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong chen Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（<20 km）, which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

A Lightweight Multiscale Feature Fusion Network for Solar Cell Defect Detection

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 521-542页

作者： Xiaoyun chen Lanyao Zhang Xiaoling chen Yigang Cen Linna Zhang Fugui Zhang School of Mechanical Engineering Guizhou UniversityGuiyang550025China School of Computer Science and Technology Beijing Jiaotong UniversityBeijing100044China

Solar cell defect detection is crucial for quality inspection in photovoltaic power generation *** the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective ***,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective *** paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these *** network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation ***,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information *** order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target ***,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter ***,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and *** and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon *** results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network.

关键词： Defect segmentation multi-scale feature fusion multi-scale attention depthwise separable residual block