检索结果-南通市图书馆

Friction of graphene on a substrate with a cavity defect

Science China(Technological Sciences) 2024年第9期67卷 2834-2841页

作者： ZHOU Peng huo ZhanLei CHANG TienChong Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai Frontier Science Center of MechanoinformaticsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China The Center for Computational Mechanics and Engineering Applications Provincial Mechanics Experimental Teaching Demonstration CenterSchool of Civil EngineeringHebei University of EngineeringHandan 056038China Shanghai Institute of Aircraft Mechanics and Control Tongji UniversityShanghai 200092China Joint-Research Center for Computational Materials Zhejiang LaboratoryHangzhou 311100China

The frictional behavior of supported graphene is known to be influenced by the physical properties and surface morphologies of the underlying substrate. However, it is unclear how a surface defect on the substrate affects the friction of supported graphene,and it is even unknown how to define the defect-induced friction force in this context. Here we conduct molecular dynamics(MD) simulations to investigate the friction between a square diamond slider and a graphene sheet supported by a copper substrate with a surface cavity defect. Our results demonstrate that the defect-induced friction exhibits a nonlinear increase with cavity size, while it decreases nonlinearly with slider size. We propose that the definition of defect-induced friction can be linked to the increase in friction work over the length of the slider, and is closely correlated to the defect-induced relative change in indentation depth and the ratio of the cavity area to the contact area. These findings provide a comprehensive evaluation of the impact of a substrate cavity defect on the friction of supported graphene and offer insights that may have broader implications for understanding defect-induced friction in other two-dimensional materials.

关键词： friction graphene underneath substrate cavity defect

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

Asymmetric dark matter and Sommerfeld enhancement

引用

Communications in Theoretical Physics 2024年第8期76卷 118-123页

作者： Sujuan Qiu Hoernisa Iminniyaz Wensheng huo School of Physics Science and Technology Xinjiang UniversityUrumqi 830017China

We study the relic density of asymmetric dark matter with long-range interactions by considering the Sommerfeld effect. We find that the annihilation cross section of asymmetric dark matter is enhanced by the Sommerfeld effect and thus the relic density is decreased. Then we use the Planck data to constrain the asymmetry factor, coupling, and to derive the upper bounds on the dark matter mass in s-wave and p-wave annihilation cases.

关键词： asymmetric dark matter relic density Sommerfeld enhancement

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

Enhancing Photovoltaic Performance of Nonfused-Ring Electron Acceptors via Asymmetric End-Group Engineering and Noncovalently Conformational Locks

引用

Chinese Journal of Chemistry 2024年第5期42卷 485-490页

作者： Bo liu Congqi li Xiaobin Gu Yinghui Han Zhixiang Wei Yunhao Cai Xin Zhang Hui Huang Yanping huo School of Chemical Engineering and light Industry Guangdong University of TechnologyGuangzhouGuangdong510006 China College of Materials Science and Opto-Electronic Technology & Center of Materials Science and Optoelectronics Engineering & CAS Center for Excellence in Topological Quantum Computation & CAS Key Laboratory of Vacuum Physics University of Chinese Academy of SciencesBeijing100049 China College Resources and Environment University of Chinese Academy of SciencesBeijing100049 China Center for Excellence in Nanoscience (CAS) & Key Laboratory of Nanosystem and Hierarchical fabrication (CAS) National Center for Nanoscience and TechnologyBeijing100190 China

By employing the asymmetric end-group engineering,an asymmetric nonfused-ring electron acceptor(NFREA)was designed and *** with the symmetric analogs(NoCA-17 and NoCA-18),NoCA-19 possesses broader light absorption range,more coplanarπ-conjugated backbone,and appropriate crystallinity according to the experimental and theoretical *** organic solar cells based on J52:NoCA-19 exhibited a power conversion efficiency as high as 12.26%,which is much higher than those of J52:NoCA-17(9.50%)and J52:NoCA-18(11.77%),mainly due to more efficient exciton dissociation,better and balanced charge mobility,suppressed recombination loss,shorter charge extraction time,longer charge carrier lifetimes,and more favorable blend film *** findings demonstrate the great potential of asymmetric end-group engineering in exploring low-cost and high-performance NFREAs.

关键词： Organic solar cells Nonfused-ring electron acceptors Asymmetric end-group engineering Noncovalently conformational locks Low-cost acceptors

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

海洋平台磁流变阻尼器振动控制模型试验

引用

中国造船 2009年第3期50卷 40-48页

作者：嵇春艳霍发力陈明璐江苏科技大学船舶与海洋工程学院江苏镇江212003

以一位于墨西哥湾的典型导管架式海洋平台为原型,根据动力相似准则按1:50比例设计海洋平台结构模型。在此基础上采用模糊控制原理设计以磁流变阻尼器(MR)为控制装置的半主动控制系统。在波浪水池中进行了多种工况模型试验,对平台在规则... 详细信息

以一位于墨西哥湾的典型导管架式海洋平台为原型,根据动力相似准则按1:50比例设计海洋平台结构模型。在此基础上采用模糊控制原理设计以磁流变阻尼器(MR)为控制装置的半主动控制系统。在波浪水池中进行了多种工况模型试验,对平台在规则波、不规则波作用下的减振效果进行了试验研究。试验结果表明,采用模糊原理设计的磁流变阻尼器半主动控制系统能够对海洋平台结构的振动进行有效的控制,且控制效果稳定。

关键词：船舶、海洋工程导管架式海洋平台磁流变阻尼器模型试验半主动控制

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

Alarm Log Data Augmentation Algorithm Based on a GAN Model and Apriori

引用

Journal of Computer Science & Technology 2024年第4期39卷 951-966页

作者： Yang Yang Yu-Ting li Yong-Hua huo Zhi-Peng Gao Lan-Lan Rui State Key Laboratory of Network and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

The complexity of alarm detection and diagnosis tasks often results in a lack of alarm log *** to the strong rule associations inherent in alarm log data,existing data augmentation algorithms cannot obtain good results for alarm log *** address this problem,this paper introduces a new algorithm for augmenting alarm log data,termed APRGAN,which combines a generative adversarial network(GAN)with the Apriori *** generates alarm log data under the guidance of rules mined by the rule ***,we propose a new dynamic updating mechanism to alleviate the mode collapse problem of the *** addition to updating the real reference dataset used to train the discriminator in the GAN,we dynamically update the parameters and the rule set of the Apriori algorithm according to the data generated in each *** extensive experimentation on two public datasets,it is demonstrated that APRGAN surpasses other data augmentation algorithms in the domain with respect to alarm log data augmentation,as evidenced by its superior performance on metrics such as BLEU,ROUGE,and METEOR.

关键词： data augmentation alarm log data Apriori generative adversarial network(GAN)

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

Experimental investigation on shear strength deterioration at the interface between different rock types under cyclic loading

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3063-3079页

作者： Qiong Wu Zhiqi liu Huiming Tang liangqing Wang Xiaoxue huo Zhen Cui Shiyu li Bo Zhang Zhiwei lin faculty of Engineering China University of GeosciencesWuhan430074China Guangxi fangchenggang Beitou Environmental Protection Water Co. Ltd.Fangchenggang538021China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The shear strength deterioration of bedding planes between different rock types induced by cyclic loading is vital to reasonably evaluate the stability of soft and hard interbedded bedding rock slopes under earthquake;however,rare work has been devoted to this subject due to lack of *** this study,experimental investigations on shear strength weakening of discontinuities with different joint wall material(DDJM)under cyclic loading were conducted by taking the interface between siltstone and mudstone in the Shaba slope of Yunnan Province,China as research objects.A total of 99 pairs of similar material samples of DDJM(81 pairs)and discontinuities with identical joint wall material(DIJM)(18 pairs)were fabricated by inserting plates,engraved with typical surface morphology obtained by performing three-dimensional laser scanning on natural DDJMs sampled from field,into mold *** shear tests were conducted on these samples to study their shear strength changes with the cyclic number considering the effects of normal stress,joint surface morphology,shear displacement amplitude and shear *** results indicate that the shear stress *** displacement curves under each shear cycle and the peak shear strength *** number curves of the studied DDJMs are between those of DIJMs with siltstone and mudstone,while closer to those of DIJMs with *** peak shear strengths of DDJMs exhibit an initial rapid decline followed by a gradual decrease with the cyclic number and the decrease rate varies from 6%to 55.9%for samples with varied surface morphology under different testing *** normal stress,joint surface morphology,shear displacement amplitude and shear rate collectively influence the shear strength deterioration of DDJM under cyclic shear loading,with the degree of influence being greater for larger normal stress,rougher surface morphology,larger shear displacement amplitude and faster shear rate.

关键词： Discontinuities with different joint wall material(DDJM) Discontinuities with identical joint wall material(DIJM) Cyclic shear test Shear strength deterioration Joint surface morphology Shear displacement amplitude Shear rate Normal stress

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

Subclinical paraganglioma of the retroperitoneum:A case report

引用

World Journal of Clinical Cases 2024年第15期12卷 2672-2677页

作者： li-Min Kang fa-Kun Yu Fu-Wei Zhang Lei Xu Department of Hepatobiliary and Pancreatic Surgery Puer People's HospitalPuer 665000Yunnan ProvinceChina

BACKGROUND Paraganglioma(PGL)located in the retroperitoneum presents challenges in diagnosis and treatment due to its hidden location,lack of specific symptoms in the early stages,and absence of distinctive manifestations on *** SUMMARY A 56-year-old woman presented with a left upper abdominal mass discovered 1 wk ago during a physical *** did not have a history of smoking,alcohol consumption,or other harmful habits,no surgical procedures or infectious diseases,and had a 4-year history of *** admission,she did not exhibit fever,vomiting,or abdominal *** examination indicated mild percussion pain in the left upper abdomen,with no palpable enlargement of the liver or *** tests and tumor markers showed no significant *** computed tomography and magnetic resonance imaging of the upper abdomen revealed a cystic solid mass in the left epigastrium measuring approximately 6.5 cm×4.5 cm,with inhomogeneous enhancement in the arterial phase,closely associated with the lesser curvature of the stomach and the *** patient underwent laparoscopic resection of the retroperitoneal mass,which was successfully removed without tumor rupture.A 12-month postoperative follow-up period showed good *** This case report details the successful laparoscopic resection of a retroperitoneal subclinical PGL,resulting in a good recovery observed at the 12-month ***,the patient also experienced unexpected cure of hypertensive disease.

关键词： Paraganglioma Retroperitoneal anatomy Subclinical Pheochromocytoma Laparoscopy Case report

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

Early systemic anticoagulation reduces hospital readmission in acute necrotizing pancreatitis patients:A retrospective cohort study

引用

Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 77-82页

作者： Wen-Jian Mao Jing Zhou Guo-Fu Zhang fa-Xi Chen Jing-Zhu Zhang Bai-Qiang li Lu Ke Wei-Qin li Department of Critical Care Medicine Jinling HospitalNanjing Medical UniversityNanjing 210002China Department of Critical Care Medicine Jinling HospitalMedical School of Nanjing UniversityNanjing 210002China National Institute of Healthcare Data Science Nanjing UniversityNanjing 210010China

Background:Early systemic anticoagulation(SAC)is a common practice in acute necrotizing pancreatitis(ANP),and its impact on in-hospital clinical outcomes had been ***,whether it affects long-term outcomes is *** study aimed to evaluate the effect of SAC on 90-day readmission and other long-term outcomes in ANP ***:During January 2013 and December 2018,ANP patients admitted within 7 days from the onset of abdominal pain were *** primary outcome was 90-day readmission after *** proportional-hazards regression model and mediation analysis were used to define the relationship between early SAC and 90-day ***:A total of 241 ANP patients were enrolled,of whom 143 received early SAC during their hospitalization and 98 did *** who received early SAC experienced a lower incidence of splanchnic venous thrombosis(SVT)[risk ratio(RR)=0.40,95%CI:0.26-0.60,Plity of life,patients who received early SAC had a significantly higher score in the subscale of vitality(P=0.03)while the other subscales were all comparable between the two *** Cox regression model showed that early SAC was an independent protective factor for 90-day readmission after adjusting for potential confounders with a hazard ratio of 0.57(95%CI:0.34-0.96,P=0.04).Mediation analysis showed that SVT mediated 37.0%of the early SAC-90-day readmission ***:The application of early SAC may reduce the risk of 90-day readmission in the survivors of ANP patients,and reduced SVT incidence might be the primary contributor.

关键词： Anticoagulation Splanchnic venous thrombosis Acute necrotizing pancreatitis Readmission Long-term outcomes

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

A nitric oxide-triggered hydrolysis reaction to construct controlled self-assemblies with complex topologies

引用

Science China Chemistry 2024年第4期67卷 1289-1299页

作者： Wenzhuo Chen Yuping Tang Shuai Chen Zipei Chen Jia He Hongbin huo Juan Zhang Jiajia li Fei Yan Wei Tian Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi Key Laboratory of Chinese Medicine Fundamentals and New Drugs ResearchCollege of PharmacyShaanxi University of Chinese MedicineXianyang 712046China Shaanxi Key Laboratory of Macromolecular Science and Technology Xi’an Key Laboratory of Hybrid Luminescent Materials and Photonic DeviceMOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural ***,utilizing the proper hydrolysis reactions to construct controlled assemblies with complex topologies is still an arduous challenge in artificial systems and needs to be ***,we report a nitric oxide(NO)-triggered slow hydrolysis strategy for the controlled construction of biomimetic supramolecular toroids(STs),thus realizing their visualization of intermediate structures and regulation of geometry *** presented protocol harnesses hydrolysis reactions to control of non-equilibrium self-assembly processes for the construction of self-assemblies with complex topologies successfully,which sheds light on how the hydrolysis reaction rate can modulate the kinetic pathway of assembly,thus realizing the artificial establishment of bio-inspired hierarchical structures.

关键词： supramolecular toroids controlled self-assembly nitic oxide-triggered hydrolysis pathway regulation

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

Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–H bond: quick access to multi-substituted aryl olefins

引用

Science China Chemistry 2024年第3期67卷 882-889页

作者： Jian Yao lili Shao Xiaohong huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct C–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–H functionalization

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

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：