检索结果-南通市图书馆

Global Energy Interconnection 2024年第2期7卷 206-216页

作者： Lu li Zeduan Zhang Wang Cai Qikang zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan Faculty of Electric Power Engineering Kunming University of Science and TechnologyKunming 650500P.R.China Brunel University London London UB83PHUnited Kingdom yunnan Power Grid Co. Ltd.Kunming 650041P.R.China

This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary *** approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the *** internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring ***,for faults external to the line,the energy is lower compared to adjacent *** is employed to decompose the collected fault current signals,allowing access to the high-frequency transient *** longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the ***,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances.

关键词： Through-type Cophase traction direct power supply system Traction network Empirical wavelet transform(EWT) Longitudinal protection

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi yu yu-ying li yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Construction technology for deep tunnels crossing superhigh-temperature fault zones with high water surges

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第8期18卷 1267-1280页

作者： Yong ZHAO Tingyu ZHU li yu Ming LU Sichuan–Xizang Railway Co. Ltd.Linzhi 860000China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610036China

The harsh environment in tunnels with high geothermal temperatures and humidity can adversely impact machinery,personnel,and *** main causes of specific problems are the unknown mechanisms of local geothermal formation,inappropriate temperature control measures,and insufficient systematic *** this study,three work sections relating to a high geothermal tunnel are:the tunnel face,middle-of-tunnel section,and outside-oftunnel section.A cooling strategy is proposed to offer technical support in achieving comprehensive cooling,overall as well as for each of the ***,a comprehensive geological survey explores the mechanism and exact location of the heat ***,grouting and centralized drainage measures are used to control the heat release of hot *** ventilation,ice chillers and other applicable measures are used to control the ambient ***,a monitoring and early warning system is established to prevent *** cooling strategy has been applied in the field with good results.

关键词： high geothermal tunnels cooling strategy comprehensive cooling measures safety and security

Hard carbon for sodium storage:Mechanism and performance optimization

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

Nano Research 2024年第7期17卷 6038-6057页

作者： Yongxin Wang Meng li yu Zhang Naiqing Zhang State Key Laboratory of Urban Water Resource and Environment School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Due to the shortage of lithium resource reserves and the pressure of rising prices,sodium-ion batteries have regained the attention of the public,and shown great potential for application in the fields of grid energy storage and low-speed vehicles to achieve the purpose of complementing lithium-ion batteries,so it is imperative to promote the commercial application of sodiumion *** sodium-ion battery anode materials,hard carbon is the material most likely to be used ***,there is still much work to be done before its *** review provides a comprehensive overview of the current research status from the following three ***,the microstructure and sodium storage active sites of hard carbon are ***,the mechanism of sodium storage in hard carbon is investigated,which can be broadly categorized into four model,“insertion–filling”,“adsorption–insertion”,“adsorption–filling”,and“multistage”.Finally,from the perspective of improving the electrochemical performance of hard carbon,the performance improvement strategies proposed in recent years are *** with the performance of hard carbon commercial products of some enterprises,the future development goal of hard carbon is prospected,hoping that all sectors of society can work hard for this common goal.

关键词： sodium-ion battery hard carbon mechanism performance optimization

Key processes of carbon cycle and sink enhancement paths in natural wetland ecosystems in China

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

Science China Earth Sciences 2024年第8期67卷 2444-2459页

作者： Jinshuai li Tianxiang HAO Meng YANG Guirui yu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration ***,the key carbon cycle processes in wetland ecosystems still lack a systematic *** the context of wetland protection and restoration,there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland *** this paper,the key processes of carbon cycle,such as photosynthetic carbon uptake,microbial carbon decomposition and carbon deposition and burial,are sorted out and summarized in four major wetland types,namely,swamp and peat wetlands,river and riparian wetlands,lake and lakeshore wetlands,and estuarine and coastal *** on the key processes of carbon cycle,three technological pathways for carbon sink multiplication are proposed,including,vegetation carbon sequestration and sink enhancement technology,soil carbon emission reduction technology and carbon deposition and burial *** key technologies under each pathway are further *** the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively ***,wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in *** will provide a scientific basis for the strategy of doubling the carbon sinks of China′s wetland ecosystems.

关键词： Wetlands Carbon cycle Carbon sinks Technology pathways Conservation and restoration

A deep learning model enabled multi-event recognition for distributed optical fiber sensing

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第3期67卷 291-307页

作者： yujiao li Xiaomin CAO Wenhao NI Kuanglu yu Institute of Information Science School of Computer and Information TechnologyBeijing Jiaotong University Beijing Key Laboratory of Advanced Information Science and Network Technology Beijing Jiaotong University

Fiber optic sensors that utilize backscattered light offer distributed real-time measurements and have been seen tremendous improvements in sensing distance and spatial resolution over the last ***, these improvements in sensor capabilities lead to a significant increase in the amount of data that needs to be processed. Traditional processing schemes are no longer adequate, so the development of novel signal processing methods is critical. Phase-sensitive optical time domain reflectometry(Φ-OTDR) is now applied in various applications for multi-event recognition, and it would usually be difficult, sometimes even unrealistic to label all the acquired samples due to its real-time and seamless monitoring nature. To fully take advantage of the information contained within the large number of unlabeled samples, which were formerly not utilized and hence wasted, we propose a semi-supervised model to boost the event classification performance of Φ-OTDR. The model extracts respectively the temporal features and the spatial bidirectional features together with a dual attention mechanism. Its classification accuracy has been improved up to 96.9%with only 1230 labeled samples. In addition, our model shows significant advantages when the number of labeled samples is reduced. Importantly, our method improves the accuracy of multi-event classification without any modification to the optical setup.

关键词： $\Phi$-OTDR event recognition semi-supervised learning mean teacher MT-ACNN-SA-BiLSTM

Visual test paper based on Au/δ-MnO_(2) hollow nanosphere oxidase-like activity regulation using hexavalent chromium as a smart switch

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 711-722页

作者： Wen-Chang zhuang Hai-yue Zhang Zhen-Yang Chen Wen-Jing Cheng Wei-Dan Na Zhao li lin Tian School of Materials and Chemical Engineering Xuzhou University of TechnologyXuzhou221018China School of Chemistry and Environmental Science Yili Normal UniversityYining835000China

Paper-based sensing platform is a point of need analytical toolkit for safety ***,the sensitivity,specificity,and simplicity are still ***,we report a novel strategy(Au/δ-MnO_(2) hollow nanosphere and 3,3′,5,5′-tetramethylbenzidine(TMB)induced test strips for signal-on detection)that can be utilized for hexavalent chromium(Cr^(6+))***,Cr^(6+)(CrO_(4)^(2−)) as a smart switch can remarkably enhance the oxidase-like activity of Au/δ-MnO_(2) hollow *** presence of Cr^(6+) can regulate the surface electronic redistribution of Au/δ-MnO_(2) and adjust the geometric configuration,which leads to the improvement in oxidase-like activity of Au/δ-MnO_(2).As a proof-of-concept application,a visual paper-based sensing platform of Cr^(6+) along with quantitative analysis by the test strips was successfully *** paper-based sensing platform exhibits a linear range with excellent selectivity for other interfering substances and lower limit of detection of 0.09μmol·L^(−1),providing a promising toolkit at-home Cr^(6+) measurement and environmental monitoring.

关键词： Point of need Colorimetric biosensing platform Au/δ-MnO_(2) hollow nanosphere Test strip Cr^(6+)

Developing ChatGPT for biology and medicine: a complete review of biomedical question answering

在线全文

学校读者我要写书评

暂无评论

Biophysics Reports 2024年第3期10卷 152-171页

作者： Qing li Lei li yu li Department of Computer Science and Engineering the Chinese University of Hong Kong

ChatGPT explores a strategic blueprint of question answering(QA) to deliver medical diagnoses, treatment recommendations, and other healthcare support. This is achieved through the increasing incorporation of medical domain data via natural language processing(NLP) and multimodal paradigms. By transitioning the distribution of text, images, videos, and other modalities from the general domain to the medical domain, these techniques have accelerated the progress of medical domain question answering(MDQA). They bridge the gap between human natural language and sophisticated medical domain knowledge or expert-provided manual annotations, handling large-scale, diverse, unbalanced, or even unlabeled data analysis scenarios in medical contexts. Central to our focus is the utilization of language models and multimodal paradigms for medical question answering, aiming to guide the research community in selecting appropriate mechanisms for their specific medical research *** tasks such as unimodal-related question answering, reading comprehension, reasoning, diagnosis, relation extraction, probability modeling, and others, as well as multimodal-related tasks like vision question answering, image captioning, cross-modal retrieval, report summarization, and generation, are discussed in detail. Each section delves into the intricate specifics of the respective method under consideration. This paper highlights the structures and advancements of medical domain explorations against general domain methods, emphasizing their applications across different tasks and datasets. It also outlines current challenges and opportunities for future medical domain research,paving the way for continued innovation and application in this rapidly evolving field. This comprehensive review serves not only as an academic resource but also delineates the course for future probes and utilization in the field of medical question answering.

关键词： ChatGPT Medical question answering Nature language processing Multimodal paradigms Large language models

Instantaneous preparation of gold-carbon dot nanocomposites for on-site SERS identification of pathogens in diverse interfaces

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2024年第6期12卷 1303-1312页

作者： YANXIAN GUO YE liU CHAOCAI LUO yuE ZHANG YANG li FEI ZHOU ZHOUYI GUO ZHENGFEI zhuang ZHIMING liU School of Electronic Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China Department of Physics University of Science and Technology of ChinaHefei 230026China MOE Key Laboratory of Laser life Science&Guangdong Provincial Key Laboratory of Laser life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China

Rapid detection of pathogens present on contaminated surfaces is crucial for food safety and public health due to the high morbidity and mortality of bacterial ***,a sensitive and efficient method for on-site identification of foodborne pathogens on anisotropic surfaces was developed by using an in situ instantaneously prepared surface-enhanced Raman scattering(SERS)*** achieve this,molybdenum-doped gallic acidderived carbon dots(MCDs)are utilized as the reductant for synthesizing Au@MCDs nanohybrids within just 3 s at ambient *** synergistic effect of the electromagnetic enhancement and charge transfer of Au@MCDs enables excellent SERS performance 10 times stronger than bare Au *** bioassay platform requires less than 5 min to complete the quantitative detection of foodborne pathogens on various microbial-contaminated interfaces with a sensitivity of 10 CFU/m *** innovative strategy breaks the long-standing limitations of SERS substrates in practical use,such as the time-consuming process,interference of residual surfactants,poor surface stability,and few application scenarios,providing a promising tool for widespread applications in biomedical research and clinical diagnostics.

关键词： temperature molybdenum consuming

A general and facile calcination method to synthesize single-site catalysts for highly efficient electrochemical CO_(2) reduction

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 3895-3901页

作者： Rui Sui Bingyan Wang Yongsheng Wang Jiajing Pei Wei Zhu Wenxing Chen Chunhui li Ailing Sun Zhongbin zhuang Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhou 450001China State Key Lab of Organic-Inorganic Composites and Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

The electrochemical CO_(2) reduction reaction(CO_(2)RR)has received widespread attention as a promising method for producing sustainable chemicals and mitigating the global ***,we demonstrate a general and facile synthetic route for the metal-nitrogen-carbon(M-N-C)type catalyst by simply calcinating metal acetate and urea with commercial carbon black,which have potential application in CO_(2)*** synthesized Ni-NC-600 catalyst has the structure of single Ni atom coordinated with one N atom and three C atoms(Ni-N_(1)C_(3)),which is suggested by X-ray absorption *** Ni-NC-600 catalyst exhibits high CO_(2)RR catalytic performance and a high CO Faraday efficiency above 98%in a wide potential range from-0.7 to-1.3 V(*** hydrogen electrode(RHE)),superior to most of the reported Ni-N-C *** work has developed a facile strategy to synthesize high performance CO_(2)RR catalyst.

关键词： nickel single atom catalyst CO_(2)reduction reaction CO production electrocatalyst