检索结果-南通市图书馆

International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 384-394页

作者： Kerui Song Zhou Li Mei Fang zhu xiao Qian Lei School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Hunan Key Laboratory of Super-Microstructure and Ultrafast Process School of Physics and electronicsCentral South UniversityChangsha 410083China Key Laboratory of Non-Ferrous Metal Materials Science and Engineering Ministry of EducationChangsha 410083China

Pure cobalt(Co)thin films were fabricated by direct current magnetron sputtering,and the effects of sputtering power and pres-sure on the microstructure and electromagnetic properties of the films were *** the sputtering power increases from 15 to 60 W,the Co thin films transition from an amorphous to a polycrystalline state,accompanied by an increase in the intercrystal pore ***,the resistivity decreases from 276 to 99μΩ·cm,coercivity increases from 162 to 293 Oe,and in-plane magnetic aniso-tropy *** the sputtering pressure decreases from 1.6 to 0.2 Pa,grain size significantly increases,resistivity significantly de-creases,and the coercivity significantly increases(from 67 to 280 Oe),which can be attributed to the increase in defect ***-pondingly,a quantitative model for the coercivity of Co thin films was *** polycrystalline films sputtered under pressures of 0.2 and 0.4 Pa exhibit significant in-plane magnetic anisotropy,which is primarily attributable to increased microstress.

关键词： cobalt thin film magnetron sputtering microstructure electromagnetic properties

Ultrahigh strength and improved electrical conductivity in an aging strengthened copper alloy processed by combination of equal channel angular pressing and thermomechanical treatment

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2024年第6期31卷 1823-1837页

作者： WANG Xu LI Zhou MENG Xiang-peng xiao zhu School of Materials Science and Engineering Central South UniversityChangsha 410083China Ningbo Boway Alloy Material Co. Ltd.Ningbo 315135China Key Laboratory of Non-ferrous Metal Materials Science and Engineering(Ministry of Education) Changsha 410083China

In this paper,equal channel angular pressing and thermomechanical treatment was employed to improve the strength and electrical conductivity of an aging strengthened Cu-Ti-Cr-Mg alloy,and the microstructure and properties of the alloy were investigated in *** results showed that the samples deformed by the combination of cryogenic equal channel angular pressing(ECAP)and rolling had good comprehensive properties after aging at 400℃.The tensile strength of the peak-aged and over-aged samples was 1120 MPa and 940 MPa,with their corresponding electrical conductivity of 14.7%IACS and 22.1%IACS,*** and cryogenic rolling introduced high density dislocations,leading to the inhibition of the softening effects and refinement of the *** a long time aging at 400℃,the alloy exhibited ultra-high strength with obvious increasing electrical *** high strength was attributed to the synergistic effect of work hardening,grain refinement strengthening and precipitation *** precipitation of a large amount of Ti atoms from the matrix led to the high electrical conductivity of the over-aged sample.

关键词： Cu-Ti alloy equal channel angular pressing rolling aging treatment high strength

Geographically and Temporally Weighted Regression in Assessing Dengue Fever Spread Factors in Yunnan Border Regions

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第5期37卷 511-520页

作者： zhu xiao Xiang WANG Song Wang LI Yan Fei ZHANG Ye Wu SU Xue Mei ZHAO xiao Tao National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Chinese Center for Disease Control and PreventionBeijing 102211China Yunnan Institute of Parasitic Diseases Pu’er 665000YunnanChina

Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-temporal variability of these factors in border *** We conducted a descriptive analysis of dengue fever’s temporal-spatial distribution in Yunnan border *** annual data from 2013 to 2019,with each county in the Yunnan border serving as a spatial unit,we constructed a GTWR model to investigate the determinants of dengue fever and their spatio-temporal heterogeneity in this *** The GTWR model,proving more effective than Ordinary Least Squares(OLS)analysis,identified significant spatial and temporal heterogeneity in factors influencing dengue fever’s spread along the Yunnan ***,the GTWR model revealed a substantial variation in the relationship between indigenous dengue fever incidence,meteorological variables,and imported cases across different *** In the Yunnan border areas,local dengue incidence is affected by temperature,humidity,precipitation,wind speed,and imported cases,with these factors’influence exhibiting notable spatial and temporal variation.

关键词： Dengue fever Meteorological factor Geographically and temporally weighted regression

Associations between Geriatric Nutrition Risk Index,bone mineral density and body composition in type 2 diabetes patients

在线全文

学校读者我要写书评

暂无评论

World Journal of Diabetes 2024年第3期15卷 403-417页

作者： xiao-xiao zhu Kai-Feng Yao Hai-Yan Huang Li-Hua Wang Department of Pediatrics The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina Department of Nursing The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina Department of Endocrinology The Second Affiliated Hospital of Nantong UniversityFirst People’s Hospital of Nantong CityNantong 226001Jiangsu ProvinceChina

BACKGROUND Type 2 diabetes mellitus(T2DM),a fast-growing issue in public health,is one of the most common chronic metabolic disorders in older *** and sarcopenia are highly prevalent in T2DM patients and may result in fractures and *** people with T2DM,the association between nutrition,sarcopenia,and osteoporosis has rarely been *** To evaluate the connections among nutrition,bone mineral density(BMD)and body composition in patients with *** We enrolled 689 patients with T2DM for this cross-sectional *** patients underwent dual energy X-ray absorptiometry(DXA)examination and were categorized according to baseline Geriatric Nutritional Risk Index(GNRI)values calculated from serum albumin levels and body *** GNRI was used to evaluate nutritional status,and DXA was used to investigate BMD and body *** forward linear regression analysis was used to identify the factors associated with BMD and skeletal muscle mass *** Of the total patients,394 were men and 295 were *** with patients in tertile 1,those in tertile 3 who had a high GNRI tended to be younger and had lower HbA1c,higher BMD at all bone sites,and higher appendicular skeletal muscle index(ASMI).These important trends persisted even when the patients were divided into younger and older *** GNRI was positively related to ASMI(men:r=0.644,P<0.001;women:r=0.649,P<0.001),total body fat(men:r=0.453,P<0.001;women:r=0.557,P<0.001),BMD at all bone sites,lumbar spine(L1-L4)BMD(men:r=0.110,P=0.029;women:r=0.256,P<0.001),FN-BMD(men:r=0.293,P<0.001;women:r=0.273,P<0.001),and hip BMD(men:r=0.358,P<0.001;women:r=0.377,P<0.001).After adjustment for other clinical parameters,the GNRI was still significantly associated with BMD at the lumbar spine and femoral ***,a low lean mass index and higherβ-collagen special sequence were associated with low BMD at all bone *** was negatively correlated with

关键词： Geriatric Nutrition Risk Index Bone mineral density Skeletal muscle mass Type 2 diabetes

A weakly-solvated ether-based electrolyte for fast-charging graphite anode

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第8期35卷 526-532页

作者： xiao zhu Yanbing Mo Jiawei Chen Gaopan Liu Yonggang Wang xiaoli Dong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Fudan UniversityShanghai 200433China

Weakly-solvated electrolytes(WSEs)utilizing solvents with weak coordination ability offer advantages for low-potential graphite anode owing to their facile desolvation process and anions-derived inorganic-rich solid electrolyte interphase(SEI)***,these electrolytes face challenges in achieving a balance between the weak solvation affinity and high ionic conductivity,as well as between rigid inorganic-rich SEI and flexible SEI for long-term ***,we introduce 1,3-dioxolane(DOL)and lithium bis(trifluoromethanesulfonyl)-imide(LiTFSI)as functional additives into a WSE based on nonpolar cyclic ether(1,4-dioxane).The well-formulated WSE not only preserves the weakly solvated features and anion-dominated solvation sheath,but also utilizes DOL to contribute organic species for stabilizing the SEI *** from these merits,the optimized electrolyte enables graphite anode with excellent fast-charging performance(210 mAh/g at 5 C)and outstanding cycling stability(600 cycles with a capacity retention of 82.0%at room temperature and 400 cycles with a capacity retention of 80.4%at high temper-ature).Furthermore,the fabricated LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||graphite full cells demonstrate stable operation for 140 cycles with high capacity retention of 80.3%.This work highlights the potential of tailoring solvation sheath and interphase properties in WSEs for advanced electrolyte design in graphite-based lithium-ion batteries.

关键词： Weakly-solvated solvent Bisalt ether-based electrolyte Graphite anode NCM||graphite battery Interfacial optimization

Revisiting the sodium-ion storage capability of hard carbon in carbonate-based electrolytes via a sodium-metal-free protocol

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第7期67卷 2240-2247页

作者： Gaopan Liu Yanbing Mo Jiawei Chen Yu Peng xiao zhu Fei Wang xiaoli Dong Yongyao Xia Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyLaboratory of Advanced MaterialsFudan UniversityShanghai 200438China

Common evaluation methodology of sodium(Na)-containing two-electrode or three-electrode configurations overlooks the interference from highly reactive Na metal,leading to the underestimation or inconsistent performance of low-potential hard carbon(HC)***,the trap of Na metal was systematically investigated with or without applied current,uncovering its inadequacy as the reference or counter electrode in different configurations.A Na-metal-free three-electrode protocol is proposed for evaluating the actual Na^(+)-storage capability of the typical low-potential HC *** avoiding Na crosstalk and precisely controlling the working electrode's potential,the actual electrochemical performance of HC in the carbonate esterbased electrolyte can be recognized with high capacity of 222 mAh g^(-1)at 2 C and 113 mAh g^(-1)at 5 C,correcting the misunderstanding of the inferior performance of HC in coin-type half cells(68%and 50%undervaluation at 2 C and 5 C,respectively).The advanced protocol is expected to reduce misunderstandings or underestimation due to evaluation methods and to guide the development of high-performance battery materials.

关键词： highly reactive sodium potential drift carbonate ester sodium-metal-free protocol sodium storage capability

铜基载氧体在化学链燃烧中的循环反应特性研究

在线全文

学校读者我要写书评

暂无评论

工程热物理学报 2024年第1期45卷 279-285页

作者：朱晓沈来宏南京工业职业技术大学南京210023 能源热转换及其过程测控教育部重点实验室东南大学南京210096

载氧体在长周期的化学链燃烧中存在严重的烧结与团聚问题,极大限制了化学链燃烧的工业化进展。本文采用流化床结晶造粒的方法,制备出一种高比表面积的铜基载氧体,在流化床热重分析仪(fluidized bed thermogravimetric analyzer,FBTGA)... 详细信息

载氧体在长周期的化学链燃烧中存在严重的烧结与团聚问题,极大限制了化学链燃烧的工业化进展。本文采用流化床结晶造粒的方法,制备出一种高比表面积的铜基载氧体,在流化床热重分析仪(fluidized bed thermogravimetric analyzer,FBTGA)上对其进行了长期化学链燃烧(chemical looping combustion,CLC)循环测试,并对反应前后的载氧体颗粒进行了还原反应实验。实验结果表明,所制备载氧体在900℃的高温下氧化还原循环120次后,其反应活性保持稳定,且并未出现明显的烧结与团聚迹象。对循环前后的载氧体颗粒进行形貌表征分析可知,此种Cu基载氧体的比表面积高达40 m^(2)/g以上,展现出良好的反应活性。此外,载氧体主要成分由CuAl_(2)O_(4)分解为Al_(2)O_(3)和CuO,其循环后仍呈光滑的球形颗粒,并维持多孔结构,活性组分Cu在颗粒表面高度分散。

关键词：化学链燃烧铜基载氧体流化床热重分析仪烧结与团聚

Artificial Intelligence Adoption for Cybersecurity in Africa

在线全文

学校读者我要写书评

暂无评论

Journal of Information Security 2024年第2期15卷 134-147页

作者： Nadine Nibigira Vincent Havyarimana zhu xiao School of Engineering Sciences University of Burundi Doctoral School Bujumbura Burundi Department of Applied Sciences Burundi Higher Institute of Education (ENS) Bujumbura Burundi College of Computer Science and Electronic Engineering Hunan University Yongzhou Hunan

Legacy-based threat detection systems have not been able to keep up with the exponential growth in scope, frequency, and effect of cybersecurity threats. Artificial intelligence is being used as a result to help with the issue. This paper’s primary goal is to examine how African nations are utilizing artificial intelligence to defend their infrastructure against cyberattacks. Artificial intelligence (AI) systems will make decisions that impact Africa’s future. The lack of technical expertise, the labor pool, financial resources, data limitations, uncertainty, lack of structured data, absence of government policies, ethics, user attitudes, insufficient investment in research and development, and the requirement for more adaptable and dynamic regulatory systems all pose obstacles to the adoption of AI technologies in Africa. The paper discusses how African countries are adopting artificial intelligence solutions for cybersecurity. And it shows the impact of AI to identify shadow data, monitor for abnormalities in data access and alert cyber security professionals about potential threats by anyone accessing the data or sensitive information saving valuable time in detecting and remediating issues in real-time. The study finds that 69.16% of African companies are implementing information security strategies and of these, 45% said they use technologies based on AI algorithms. This study finds that a large number of African businesses use tools that can track and analyze user behaviour in designated areas and spot anomalies, such as new users, strange IP addresses and login activity, changes to permissions on files, folders, and other resources, and the copying or erasure of massive amounts of data. Thus, we discover that just 18.18% of the target has no national cybersecurity strategy or policy. The study proposes using big data security analytics to integrate AI. Adopting it would be beneficial for all African nations, as it provides a range of cyberattack defense techn

关键词： Artificial Intelligence (AI) Cybersecurity Cyberattacks Cybercriminals

Sensitive Information Security Based on Elliptic Curves

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Engineering and Technology 2024年第2期12卷 274-285页

The elliptic curve cryptography algorithm represents a major advancement in the field of computer security. This innovative algorithm uses elliptic curves to encrypt and secure data, providing an exceptional level of security while optimizing the efficiency of computer resources. This study focuses on how elliptic curves cryptography helps to protect sensitive data. Text is encrypted using the elliptic curve technique because it provides great security with a smaller key on devices with limited resources, such as mobile phones. The elliptic curves cryptography of this study is better than using a 256-bit RSA key. To achieve equivalent protection by using the elliptic curves cryptography, several Python libraries such as cryptography, pycryptodome, pyQt5, secp256k1, etc. were used. These technologies are used to develop a software based on elliptic curves. If built, the software helps to encrypt and decrypt data such as a text messages and it offers the authentication for the communication.

关键词： Cryptography Elliptic Curves Digital Security Data Sensitive Data Implementation

从“时代精神的对立”到“方法论的冲突”:人文主义-经院哲学之争研究范式的演变

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

史学理论研究 2024年第3期 100-114,159页

作者：朱晓山东师范大学历史文化学院 250399

西方学界围绕人文主义-经院哲学之争的研究,经历了传统学派、修正学派和新修正学派三种范式。19世纪末,受布克哈特文艺复兴观影响的现代化叙事范式,将该论争解释为两种时代精神的对立与冲突;20世纪40年代,受克里斯特勒去意识形态化的人... 详细信息

西方学界围绕人文主义-经院哲学之争的研究,经历了传统学派、修正学派和新修正学派三种范式。19世纪末,受布克哈特文艺复兴观影响的现代化叙事范式,将该论争解释为两种时代精神的对立与冲突;20世纪40年代,受克里斯特勒去意识形态化的人文主义观念影响的修正学派,主张人文学科与经院哲学是大学中两个相互独立、共存的学科,二者之间并无实质的冲突;20世纪70年代,意识到“巴伦-加林路线”合理性的新修正学派,既承认双方在意大利文艺复兴阶段共存的合理性,也正视二者在北方文艺复兴阶段由于方法论的对立而引发的矛盾与冲突。这三种研究范式及其演变,体现了百余年间西方学界对文艺复兴时期人文主义的构建与意识形态之间紧密而复杂的关联,呈现了史学与时代的互动。

关键词：文艺复兴人文主义经院哲学宗教改革