检索结果-南通市图书馆

Simultaneous surface modification method for 0.4Li2MnO3-0.6LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries： Acid treatment and LiCoPO4 coating

引用

Nano Research 2017年第12期10卷 4210-4220页

作者： Min-Joon Lee Eunsol Lho Pilgun Oh Yoonkook son Jaephil Cho Department of Energy Engineering School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology(UNIST) Ulsan 44919 Republic of Korea

Li-rich layered cathode materials have been considered the most promising candidates for large-scale Li-ion batteries due to their low cost and high reversible capacity. However, these materials have many drawbacks that hinder commercialization, such as low initial efficiency and cyclability at elevated temperatures. To overcome these barriers, we propose an efficient and effective surface modification method, in which chemical activation （acid treatment） and LiCoPO4 coating were carried out simultaneously. During the synthesis, the lithium ions were extracted from the lattice, leading to improved Columbic efficiency, and these ions were used for the formation of LiCoPO4. The Ni and Co doped spinel phase was formed at the surface of the host material, which gives rise to the facile pathway for lithium ions. The LiCoPO4 and highly doped spinel on the surface acted as double protection layers that effectively prevented side reactions on the surface at 60℃. Moreover, the transition metal migration of the modified cathode was weakened, due to the presence of the spinel structure at the surface. Consequently, the newly developed Li-rich cathode material exhibited a high 1st efficiency of 94%, improved capacity retention of 82% during 100 cycles at 60℃, and superior rate capability of 62% at 12C （1C = 200 mA/g） rate at 24℃. In addition, the thermal stability of the modified cathode was significantly improved as compared to that of a bare counterpart at 4.6 V, showing a 60% decrease in the total heat generation.

关键词： lithium ion battery cathode material Li-rich material electrochemistry surface modification

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

Simultaneous lateral and subxiphoid access methods for safe and accurate resection of a superior vena cava aneurysm:A case report

引用

World Journal of Clinical Cases 2023年第31期11卷 7635-7639页

作者： Sang Pil Kim Joohyung son Department of Thoracic and Cardiovascular Surgery Kyunghee University HospitalSeoul 02447South Korea Department of Thoracic and Cardiovascular Surgery Pusan National University Yangsan HospitalYangsan-si 50612South Korea

BACKGROUND Superior vena cava(SVC)aneurysms are a relatively uncommon disease that has not been widely *** conventional surgical approach for treating SVC aneurysms includes open thoracotomy and ***,in this case,the aneurysm could be safely resected by thoracoscopic simultaneous lateral and subxiphoid access *** SUMMARY A 58-year-old male presented with intermittent chest pain and persistent discomfort in the chest area.A chest computed tomography scan revealed a 6.2 cm aneurysm in the left innominate vein and SVC *** surgical resection,simultaneous lateral and subxiphoid access were planned to achieve optimal proximal and distal aneurysm *** approach site was 1 cm below the xiphoid process,the fifth mid-axillary line and the seventh anterior axillary line on the right *** aneurysm was resected using a *** patient was discharged on the third day after chest tube removal on the second postoperative day with no particular *** Aneurysms located within the mediastinum can be accessed through thoracoscopic approach without open surgery and safely resected using vascular staples.

关键词： Aneurysm Cardiopulmonary bypass Superior vena cava Minimal invasive surgery Video assisted thoracic surgery 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

Expression of Genes Affecting Skin Coloration and Sugar Accumulation in Apple Fruits at Ripening Stages in High Temperatures

引用

World Journal of Engineering and Technology 2015年第3期3卷 7-12页

作者： Seon Ae Kim Soon Young Ahn Hyun Hee Han In Chang son Hae keun Yun Department of Horticulture and Life Science Yeungnam University Gyeongsan South Korea National Institute of Horticultural & Herbal Science Wanju South Korea

High temperature is one of the most important environmental factors that affect the successful cultivation of apple (Malus × domestica Borkh). The expression of genes related with anthocyanin synthesis and sugar accumulation by high temperature treatment was investigated in the fruits of “Fuji” apple at different developmental stages in different temperature conditions through real- time PCR. In the initial ripening stages in fruits, there was high expression of genes associated with fruit ripening, flavonoid compound accumulation, and coloration in high temperatures. Expression of phenylalanine ammonia-lyase, chalcone synthase, flavone 3-hydrogenase, and malate dehydrogenase genes increased gradually in initial ripening stages, while sharply reduced at 24 hr after treatment. In addition, there was no significant difference in the expression of all temperature treatments in late ripening stages. In the further work, investigation of expression levels of various genes could be conducted in the level of transcriptomes from fruits at the early stages to get meaningful information of ripening metabolism in apples in high temperatures.

关键词： Anthocyanin Apple High Temperature Skin Coloration Sugar Content

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

Two-stage dynamic recrystallization and texture evolution in Al-7Mg alloy during hot torsion

引用

International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1900-1911页

作者： Kwang Tae son Chang Hee Cho Myoung Gyun Kim Ji Woon Lee School of Mechanical Industrialand Manufacturing EngineeringOregon State UniversityCorvallis OR 97331USA Department of Materials Science Engineering Northwestern UniversityEvanston IL 60208USA Research Institute of Industrial Science and Technology(RIST) Pohang 37673Rep.of Korea Division of Advanced Materials Engineering Kongju National UniversityCheonan 31080Rep.of Korea Center for Advanced Materials and Parts of Powders Kongju National UniversityCheonan 31080Rep.of Korea

Hot torsion tests were performed on the Al-7Mg alloy at the temperature ranging from 300 to 500℃ and strain rates between 0.05 and 5 s^(-1) to explore the progressive dynamic recrystallization(DRX)and texture *** DRX behavior of the alloy manifested two distinct stages:Stage 1 at strain of≤2 and Stage 2 at strains of≥*** Stage 1,there was a slight increase in the DRXed grain fraction(X_(DRX))with predominance of discontinuous DRX(DDRX),followed by a modest change in X_(DRX) until the transition to Stage *** 2 was marked by an accelerated rate of DRX,culminating in a substantial final X_(DRX) of~*** backscattered diffraction(EBSD)analysis on a sample in Stage 2 revealed that continuous DRX(CDRX)predominantly occurred within the(121)[001]grains,whereas the(111)[110]grains underwent a geometric DRX(GDRX)evolution without a noticeable sub-grain ***,a modified Avrami’s DRX kinetics model was utilized to predict the microstructural refinement in the Al-7Mg alloy during the DRX *** this kinetics model did not accurately capture the DDRX behavior in Stage 1,it effectively simulated the DRX rate in Stage *** texture index was employed to assess the evolution of the texture isotropy during hot-torsion test,demonstrating significant improvement(>75%)in texture randomness before the commencement of Stage *** initial texture evolution is attributed to the rotation of parent grains and the substructure evolution,rather than to an increase in X_(DRX).

关键词： Al-7Mg alloys hot deformation hot torsion tests dynamic recrystazlliation microstructure texture

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

Mixed-dimensional stacked nanocomposite structures for a specific wavelength-selectable ambipolar photoresponse

引用

Nano Research 2024年第6期17卷 5549-5558页

作者： Young Jae Park Jaeho Shim Joo song Lee Kyu Seung Lee Ji-Yeon Kim Kang Bok Ko Sang-Youp Yim Seongjun Kim Hoon-Kyu Shin Donghee Park yong Ju Yun Dong Ick son Institute of Advanced Composite Materials Korea Institute of Science and TechnologyJeollabuk-do 55324Republic of Korea National Institute for Nanomaterials Technology Pohang University of Science and TechnologyGyeongsangbuk-do 37673Republic of Korea Department of Semiconductor Science and Technology Semiconductor Physics Research CenterJeonbuk National UniversityJeonju 54896Republic of Korea Advanced Photonics Research Institute Gwangju Institute of Science and TechnologyGwangju 61005Republic of Korea Center for Opto-Electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and TechnologySeoul 02792Republic of Korea Graduate School of Energy and Environment(KU-KIST Green School) Korea UniversitySeoul 02841Republic of Korea KIST School Department of Nanomaterials and Nano ScienceUniversity of Science and Technology(UST)Daejeon 34113Republic of Korea

Mixed-dimensional composite structures using zero-dimensional(0D)quantum dots(QDs)and two-dimensional(2D)transition metal dichalcogenides(TMDs)materials are expected to attract great interest in optoelectronics due to the potential to generate new optical ***,we report on the unique optical characteristics of a devices with mixed dimensional vertically stacked structures based on tungsten diselenide(WSe_(2))/CdSeS QDs monolayer/molybdenum disulfide(MoS_(2))(2D/0D/2D).Specifically,it exhibits an ambipolar photoresponse characteristic,with a negative photoresponse observed in the 400-600 nm wavelength range and a positive photoresponse appeared at 700 nm *** resulted in the high negative responsivity of up to 52.22 mA·W^(−1)under 400 nm,which is 163 times higher than that of the photodetector without CdSeS *** also demonstrated the negative photoresponse,which could be due to increased carrier collision probability and non-radiative *** modeling and simulation reveal that Auger recombination among the types of non-radiative recombination is the main cause of negative photocurrent ***,we discovered ambipolar photoresponse near a specific wavelength corresponding to the energy of quantum *** study revealed interesting phenomenon in the mixed low-dimensional stacked structure and paved the way to exploit it for the development of innovative photodetection materials as well as for optoelectronic applications.

关键词： mixed-dimension quantum dot heterostructure photodetector ambipolar photoresponse

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

Improved speech absence probability estimation based on environmental noise classification

引用

Journal of Central South University 2012年第9期19卷 2548-2553页

作者： son Young-ho LEE Sang-min Department of Electronic Engineering Inha University Institute for Information and Electronics Research Inha University

An improved speech absence probability estimation was proposed using environmental noise classification for speech enhancement.A relevant noise estimation approach,known as the speech presence uncertainty tracking method,requires seeking the "a priori" probability of speech absence that is derived by applying microphone input signal and the noise signal based on the estimated value of the "a posteriori" signal-to-noise ratio(SNR).To overcome this problem,first,the optimal values in terms of the perceived speech quality of a variety of noise types are ***,the estimated optimal values are assigned according to the determined noise type which is classified by a real-time noise classification algorithm based on the Gaussian mixture model(GMM).The proposed algorithm estimates the speech absence probability using a noise classification algorithm which is based on GMM to apply the optimal parameter of each noise type,unlike the conventional approach which uses a fixed threshold and smoothing *** performance of the proposed method was evaluated by objective tests,such as the perceptual evaluation of speech quality(PESQ) and composite *** was then evaluated by a subjective test,namely,mean opinion scores(MOS) under various noise *** proposed method show better results than existing methods.

关键词： speech enhancement soft decision speech absence probability Gaussian mixture model (GMM)

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

JA but not JA-Ile is the cell-nonautonomous signal activating JA mediated systemic defenses to herbivory in Nicotiana attenuata

引用

Journal of Integrative Plant Biology 2017年第8期59卷 552-571页

作者： Tobit A. Bozorov son Truong Dinh Ian T. Baldwin Department of Molecular Ecology Max Planck Institute for Chemical EcologyHans-Knoll-Str.8D-07745JenaGermany Institute of Genetics and Plants Experimental Biology Uzbek Academy of SciencesYukori-Yuz111226KibrayTashkent RegionUzbekistan Department of Plant Biotechnology Faculty of Biotechnology-Vietnam National University of AgricultureNgo Xuan Quang Street100000HanoiVietnam

The whole-plant activation of defense responses to wounding and herbivory requires systemic signaling in which jasmonates （JAs） play a pivotal role. To examine the nature of the slower cell-nonautonomous as compared to the rapid cell-autonomous signal in mediating systemic defenses in Nicotiana attenuata, reciprocal stem graftingexperiments were used with plants silenced for the JA biosynthetic gene ALLENE OXIDE CYCLASE （irAOC） or plants transformed to create JA sinks by ectopicalIy expressing Arabidopsis JA-O-methyltransferase （ovJMT）. JA-impaired irAOC plants were defective in the cell-nonautonomous signaling pathway but not in JA transport. Conversely, ovJMT plants abrogated the production of a graft-transmissible JA signal. Both genotypes displayed unaltered cell-autonomous signaling. Defense responses （17-hydroxygeranyllinalool diterpene glycosides, nicotine, and proteinase inhibitors） and metabolite profiles were differently induced in irAOC and ovJMT scions in response to graft-transmissible signals from elicited wild type stocks. The performance of Manduca sexta larvae on the scions of different graft combinations was consistent with the patterns of systemic defense metabolite elicitations. Taken together, we conclude that JA and possibly MeJA, but not JA-lle, either directly functions as a long-distance transmissible signal or indirectly interacts with long distance signal（s） to activate systemic defense responses.

关键词： COYOTE tobacco JASMONATE GENOTYPE METABOLITES ALLENE oxide cyclase

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

Structural stability estimation of whirling unit

引用

中国有色金属学会会刊：英文版 2009年第B09期19卷 202-208页

作者： son-Jae HWAN Han-Chang WOO Lee-Sang Ryong Lee-Young MOON Daegu Machinery Institute of Component & Materials Foundation Department of Automobile Yeungnam College of Science & Technology Department of Mechanical Engineering Kyung pook National University

Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by using ADAMS and NASTRAN softwares. Each maximum force acting on the bearing attached to the spindle assembly and the cutting tool attached to the whirling ring with the rotating speed of 6 000 r/min was 235 N and 902 N respectively. The maximum stress of 0.74 MPa on the base frame is far smaller than the yield strength of 282 MPa. The calculated natural frequency of 148 Hz of the system is far from the frequency of the driving speed of 6 000 r/min. The experimentally obtained maximum cutting force of 792 N is smaller than that of calculated value. And the experimentally obtained natural frequency of 118 Hz is beyond the driving speed of 6000 r/min. From above results it can be judged that the whirling system is statically and dynamically stable.

关键词：旋转工件稳定性评价 NASTRAN软件动态稳定性结构单元固有频率行车速度

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

Deformation prediction of porcelain-enameled steels with strain history by press forming and high-temperature behavior of coating layer

引用

中国有色金属学会会刊：英文版 2012年第S3期22卷 838-844页

作者： Young-Ki son Chan-Joo LEE Jung-Min LEE Byung-Min KIM School of Mechanical Engineering Pusan National University Dongnam Regional Division Korea Institute of Industrial Technology

Porcelain enamel coatings were widely applied for the protection of steel products because they offered high corrosion protection,resistance to heat and abrasion,high hardness,hygiene and ease of *** typical process to produce enameled steels is roughly divided into two stages:the first stage consists of a forming process to give the desired shape to a steel substrate,and the second stage consists of a firing process to bond enamel frits on the *** firing process requires a high temperature above 800 °C,which may lead to austenitic transformation and severe thermal deformation of the steel *** aim of this study is to develop a finite element analysis (FE analysis) technique to predict the mechanical and thermal deformations of the enameled steels during forming and any further enameling process,including *** FE analysis involves analyzing the strain history of the steel substrate,which comprises the stress and thickness distributions of the substrate and its deformed shape,and the high-temperature behavior of the enamel coating *** validity of the FE analysis is verified through the U-bending test and firing test with various numbers and positions of enamel coating layers on the *** results reveal that the FE analysis results agree well with the experimental results with 8% error.

关键词： porcelain enamel firing process finite element analysis enameled steel thermal deformation

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

Effects of Momentum Ratio and Weber Number on Spray Half Angles of Liquid Controlled Pintle Injector

引用

Journal of Thermal Science 2015年第1期24卷 37-43页

作者： Min son Kijeong Yu Jaye Koo Oh Chae Kwon Jeong Soo Kim Korea Aerospace University School of Aerospace and Mechanical Engineering Korea Aerospace University School of Mechanical Engineering Sungkyunkwan University Department of Mechanical Engineering Pukyong National University

A pintle injector is advantageous for throttling a liquid rocket engine and reducing engine weight. This study ex- plores the effects of momentum ratio and Weber number at various injection conditions on spray characteristics of the pintle injector for liquid-gas propellants. A liquid sheet is injected from a center pintle nozzle and it is broken by a gas jet from an annular gap. The pressure drops of propellants, and the pintle opening distance were consi- dered as control variables; using 0.1 -1.0 as a bar for the pressure drop of the liquid injection, a 0.01-4）.2 bar for the pressure drop of gas jet and a 0.2 - 1.0 mm for the pintle opening distance. The discharge coefficient was de- creased linearly before the pintle opening distance of 0.75 mm and then, the coefficient was slightly increased. Spray images were captured by a CMOS camera with high resolution. Then, the shadow and reflected images were analyzed. Spray distributions were measured by a pattemator with an axial distance of 50 mm from a pintle tip. Finally, the spray half angles had an exponentially decreasing correlation as a momentum ratio divided by the Weber number. Also, the spray half angles from the spray distribution were underestimated compared to those measured from the captured images.

关键词： Pintle Injector Spray Half Angle Spray Distribution Visualization

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：