检索结果-南通市图书馆

Thixocasting combination spanners using stainless steel X39CrMo17

中国有色金属学会会刊：英文版 2010年第S3期20卷 998-1004页

作者： M.BüNCk.E.SUBASIC A.BüHRIG-POLACZEk.k.JIANG S.MüNSTERMANN J.M.SCHNEIDER k.FICk.RT H.J.GüNTHER Foundry Institute at RWTH Aachen University AachenGermany Materials Chemistry at RWTH Aachen University AachenGermany HAZET-Hermann Zerver GmbH & Co.k. RemscheidGermany PlaTeG GmbH SiegenGermany

Forging is state-of-the-art for producing hand tools on an industrial *** to high demands on the stiffness and the fracture toughness,high-strength forging steels were used to provide cavity-free components with high mechanical load ***,forging is a cost-effective mass production process but,in spite of all its advantages,it has its limitations,*** the freedom of ***,because of the extreme thermal loading(particularly with regard to permanent moulds) and the frequently unavoidable casting defects,hand tools are not *** means of thixocasting steel,technical difficulties can be reduced and new options are provided which allow the manufacturing of components with much higher complexity than that using *** near-net shape production,manufacturing steps and costs can be ***,steels,which are difficult to forge but nonetheless have high potential for specific applications(such as high strength or corrosion resistant steels),can also be *** cooperation with industrial partners,X39CrMo17 stainless steel combination spanners with 17 mm width across flats were *** dies were designed and optimized by simulation,the hot forming X38CrMoV5 tool steel as well as the molybdenum alloy TZM were selected as the tool *** dies were treated by a plasma nitriding process and subsequently coated with crystalline Al2O3 protective coatings by plasma-enhanced chemical vapor deposition(PECVD).During the experiments,combination spanners were successfully cast in the semi-solid *** parts were heat-treated to enhance the toughness of components,which was subsequently measured by a standardized torque ***,a hypothetical approach of a possible,industrial batch process was carried out using the simulation software MAGMAsoft.

关键词： thixocasting X39CrMo17 steel casting semi-solid MAGMAsoft simulation

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

Proton transport controlled at surface layer of CeO_(2) by gradient-doping with a built-in-field effect

引用

Journal of Rare Earths 2023年第12期41卷 2025-2032,I0008页

作者： Yuzheng Lu Naveed Mushtaq M.A.k.Yousaf Shah Sajid Rauf Chen Xia Bin Zhu School of Electronic Engineering Nanjing Xiaozhuang UniversityNanjing21171China School of Physics Electronics and Intelligent ManufacturingHuaihua UniversityHuaihua418008China Jiangsu Provincial k.y Laboratory of Solar Energy Science and Technology/Energy Storage Joint Research Center School of Energy and EnvironmentSoutheast UniversityNanjing210096China College of Electronics and Information Engineering Shenzhen UniversityShenzhen58000China Faculty of Physics and Electronic Science Hubei UniversityWuhan430062China

Ceramic fuel cells hold an important position for the sustainable energy future using renewable energy sources with high *** design and synthesis of active materials,interface engineering and having capability of low operating temperature is considered as an important factor to further increase the power output and stability of ceramic fuel cell devices.A novel methodology has vital importance to develop new functionalities of existing materials by introducing new different *** built-in electric field(BIEF) is one of the most recently used approaches to improve charge transfer and ionic conductivity of solid oxide ***,we demonstrate gradient doping strategy in CeO_(2)-δstructure to produce BIEF effect and to modulate the proton transport effectively at the surface layer rather than bulk.*** inclusions of La and Sr metal ions at the surface and Co-metal ions into bulk.layer of CeO_(2)form the gradiently doped *** gradient doping into CeO_(2)highly improves the proton transport properties through the surface layer by modifying the energy ***,unbalanced charge distribution due to gradient doping produces built-in electric-field to provide extra driving force for protons transport through surface *** acquired gradiently doped fluorite structure exhibits remark.ble proton conductivity of>0.2 S/cm,as a result ceramic fuel cell shows power output of>1000 mW/cm2while operating at 500℃.This unique work.highlights the critical role of gradiently doped electrolyte in electrochemical conversion energy devices and offers new understanding and practices for sustainable energy future.

关键词： La_(0.20)Sr_(0.05)Ce_(0.65)Co_(0.1)0_(2-δ)(LSCC) Gradient doping Fast protonic transport High grain boundary conduction Built-in electric field Rare earths

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

EFFICIENT BOX-CONSTRAINED TV-TYPE-l^1 ALGORITHMS FOR RESTORING IMAGES WITH IMPULSE NOISE

引用

Journal of Computational Mathematics 2013年第3期31卷 249-270页

作者： Liyan Ma Michael k. Ng Jian Yu Tieyong Zeng School of Computer and Information Technology Beijing Jiaotong University Beijing 100044 China Department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, we study the restoration of images simultaneously corrupted by blur and impulse noise via variational approach with a box constraint on the pixel values of an image. In the literature, the TV-l^1 variational model which contains a total variation （TV） regularization term and an l^1 data-fidelity term, has been proposed and developed. Several numerical methods have been studied and experimental results have shown that these methods lead to very promising results. However, these numerical methods are designed based on approximation or penalty approaches, and do not consider the box constraint. The addition of the box constraint mak.s the problem more difficult to handle. The main contribution of this paper is to develop numerical algorithms based on the derivation of exact total variation and the use of proximal operators. Both one-phase and two-phase methods are considered, and both TV and nonlocal TV versions are designed. The box constraint [0, 1] on the pixel values of an image can be efficiently handled by the proposed algorithms. The numerical experiments demonstrate that the proposed methods are efficient in computational time and effective in restoring images with impulse noise.

关键词： Image restoration Impulse noise Total variation Nonlocal total variation Proximal Operators.

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

Enhanced thermoelectric performance of spark.plasma sintered p-type Ca_(3-x)Y_(x)Co_(4)O_(9+δ)systems

引用

Journal of Materials Science & Technology 2020年第20期52卷 212-222页

作者： J.S.Cha D.H.k.m H.Y.Hong k.Park Faculty of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul05006Republic of Korea

Highly textured dense Ca3-xYxCo4 O9+δ(0≤x≤0.3)samples were fabricated by combining sol-gel process with spark.plasma sintering(SPS).Y^3+substitution for Ca^2+simultaneously increased the Seebeck.coefficient and reduced the thermal *** latter was attributed to the increase in lattice anharmonicity,structural distortion,and grain boundary area,which enhanced the phonon ***2.7Y0.3Co4 O9+δshowed the largest dimensionless figure-of-merit(ZT=0.194)at 1073 k.because it had the largest Seebeck.coefficient and the lowest thermal *** ZT value was 55%larger than that of undoped Ca3 Co4 O9(0.125 at 1073 k..Therefore,Y^3+substitution,sol-gel powder synthesis,and SPS are highly effective for enhancing the thermoelectric prope rties of Ca_(3)Co_(4)O_(9).

关键词： Electrical conductivity Ca_(3)Co_(4)O_(9) Thermoelectric properties Seebeck.coefficient Thermal conductivity Spark.plasma sintering

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

The Local Process of Governance in Integrated Water Resource Management： An Example of the Wadi El k.bir Watershed （Northeast of Algeria）

引用

Journal of Environmental Science and Engineering 2011年第10期5卷 1297-1302页

作者： D. Zouini k. k.anchoul Department of Geology Badji Mokhtar University Annaba Annaba 23000 Algeria

Alternatives to the sectoral and public policies and regulations of environmental and water resources＇ protection, and the experiments of integrated management have been rapidly multiplied since the year 1990. Water constitutes a principal stak. of these environmental policies in the majority of the countries and especially in the countries of North Africa as Algeria, where this resource is threatened by repeated dryness and by the impact of the climate change. The integrated water resource management reflects today the world tendency of the governments to exploit and preserve this resource by a way based on a process of governance, which passes by the dialog of diversified actors （various sectors）. According to this policy and to the promulgation of the Algerian National Report on State effective implementation and coordination mechanisms are required. How this principle of integrated water management will be executed with various scenarios in Algeria and what are the main difficulties that can be met？ Or, more exactly, what are the variables that can influence the operation of the local water process governorship？ This analysis will be carried out through the example of the Wadi El k.bir watershed located in the northeast of Algeria, which is real natural area of water supply that feeds the communities, the natural and artificial basins, and preserves the perenniality of the existing natural ecosystems especially the one of the natural park.classified by the United Nations Educational Scientific and Cultural Organization （U.N.E.S.C.O） in 1989 as the inheritance of humanity and six other sites classified according to the Ramsar convention as wetlands of international importance to be preserved.

关键词： Water resource integrated management diagram of water installation watershed governance multi-actors RNE Algeria.

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

Influence of graphene nanoplatelets on mechanical properties and adhesive wear performance of epoxy-based composites

引用

Friction 2021年第4期9卷 856-875页

作者： k.Y.EAYAL AWWAD B.F.YOUSIF k.osro FALLAHNEZHAD k.alid SALEH Xuesen ZENG Faculty of Health Engineering and SciencesUniversity of Southern QueenslandToowoombaQLDAustralia Centre for Future Materials University of Southern QueenslandToowoombaQLDAustralia School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLDAustralia

Epoxy resin is one of the most widely used thermoset polymers in high-performance composite materials for lightweight ***,epoxy has a high coefficient of friction,which limits its tribological *** this study,the effect was investigated of different weight fractions of solid lubricant graphene nanoplatelets(GNPs),ranging from 0 to 4.5 wt%,on mechanical and adhesive wear performance of *** wear tests covered mild and severe wear *** correlation of tribological and mechanical properties was studied as *** electron microscopy(SEM)was used to observe the failure mechanisms for both tribological and mechanical samples after each *** results revealed that the addition of GNPs to the epoxy improved its stiffness and hardness but reduced its fracture strength and *** wear performance exhibited high efficiency with GNP additions and showed reductions in the specific wear rate,the coefficient of friction,and the induced interface temperature by 76%,37%,and 22%,respectively.A fatigue wear mechanism was predominant as the applied load *** importantly,severe wear signs occurred when the interface temperature reached the heat distortion temperature of the *** tribological,and mechanical properties showed only a weak.correlation to each *** addition of GNPs to epoxy by less than 4.5 wt%was highly efficient to improve the wear performance while maintaining the fracture strength and *** transform infrared spectroscopy(FTIR)analysis shows no chemical interaction between the epoxy matrix with GNPs,which implies its physical interaction.

关键词： graphene nanoplatelets epoxy adhesive wear solid lubricants

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

Electrical Conductivity of Sintered Chromia Mixed with TiO_2,CuO and Mn-Oxides

引用

Journal of Materials Science & Technology 2006年第2期22卷 245-251页

作者： k.El-Menshawy H.P.Buchk.emer F.Tietz D.Stoever Metallurgy Dept. Atomic Energy Authority CairoEgypt Institute for Materials and Processes in Energy Systems IWV-1 Forschungszentrum Juelich GmbH JuelichGermany Institute for Materials and Processes in Energy Systems IWV-1 Forschungszentrum Juelich GmbH Juelich Germany

The electrical conductivity of sintered Cr2O3 mixed with 2% and 5% （in molar fraction） TiO2 or CuO was investigated in the temperature range 500-900℃ in air and in At/4 vol. pct H2 atmospheres. The effect of different Mn-oxides on the electrical conductivity of Cr2O3 was also studied under the same conditions. From the conductivity measurements it is established that additions of TiO2 change the defect structure of Cr2O3 and the effect of TiO2 on the electrical conductivity is controlled by TiO2 concentration as well as temperature and O2 partial pressure of the surrounding atmosphere. The conductivity of Cr2O3 increased in air and decreased in the At/H2 atmosphere by CuO additions. The effect of CuO was discussed with possible changes in the defect concentration in Cr2O3. Mixing of Cr2O3 with different Mn-oxides at the same Mn to metal atom fraction decreased the conductivity in air and in Ar/H2 atmospheres. No clear correlation between the spinel fraction and the changes in conductivity could be found.

关键词： Electrical conductivity Cr2O3 Mixing with TiO2 CuO Mn-oxides

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

Recent Advances on the Study of the Proterozoic Geological Evolution of Sri Lank.： International Symposium and Field Work.hop of lGCP-440 and LEGENDS Proposal

引用

Episodes 2003年第4期26卷 320-322页

作者： MasaruYoshida k.V.Wilbertk.helpannala GondwanaInstituteforGeologyandEnvironmentHashiramoto147-2Hashimoto648-0091JAPAN InstituteofFundamentalStudiesHantanaRoad KandySRILANKA

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

Bubble-lik. Fe-encapsulated N,S-codoped carbon nanofibers as efficient bifunctional oxygen electrocatalysts for robust Zn-air batteries

引用

Nano Research 2020年第8期13卷 2175-2182页

作者： Yiyi She Jin Liu Hongk.ng Wang Li Li Jinsong Zhou Michael k.H.Leung Ability R&D Energy Research Centre School of Energy and EnvironmentCity University of Hong KongHong KongChina Center of Nanomaterials for Renewable Energy(CNRE) State Key Lab of Electrical Insulation and Power EquipmentSchool of Electrical EngineeringXi’an Jiaotong UniversityXi’an710049China School of Automotive and Traffic Engineering Jiangsu University of TechnologyChangzhou213001China

Nano Research volume 13,pages2175–2182(2020)Cite this article 208 Accesses 1 Altmetric Metrics details Abstract Efficient,robust and cost-effective bifunctional oxygen electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are of vital importance to the widespread utilization of Zn-air *** we report the fabrication of a bubble-lik. N,S-codoped porous carbon nanofibers with encapsulated fine Fe/Fe5C2 nanocrystals(∼10 nm)(FeNSCs)by a facile one-pot pyrolysis *** novel FeNSC nanostructures with high Fe content(37.3 wt.%),and synergetic N and S doping demonstrate remark.ble ORR and OER catalytic activities in alk.line *** for ORR,the optimal FeNSC catalyst exhibits superior performance in terms of current density and durability in both alk.line and acidic ***,as catalysts on the air electrodes of Zn-air batteries,the optimal FeNSCs show a high peak.power density of 59.6 mW/cm^2 and extraordinary discharge-charge cycling performance for 200 h with negligible voltage gap change of only 8%at current density of 20 mA/cm,surpassing its noble metal counterpart(***).The impressive battery stability can be attributed to favorable electron transfer resulting from appropriate graphitization of the bubble-lik. carbon nanofibers and thorough protection of Fe/Fe5C2 nanoparticles by carbon wrapping to prevent oxidation,agglomeration and dissolution of Fe nanoparticles during battery *** present FeNSC catalyst,which is highly active,robust yet affordable,shows promising prospects in large-scale applications,such as metal-air batteries and fuel cells.

关键词： bifunctional catalyst heteroatom doping FeNSC catalyst oxygen reduction reaction oxygen evolution reaction

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

Robust color purity of reddish-orange emission from Sm^(3+)-activated La10W22O81 biocompatible microphosphors for solid state lighting and anticancer applications

引用

Journal of Rare Earths 2023年第12期41卷 1850-1859,I0001页

作者： k.Naveen k.mar L.Vijayalak.hmi Gayeon Lee Gumin k.ng Jiseok.Lim Jungwook.Choi School of Mechanical Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea Department of Automotive Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea School of Mechanical Engineering Chung-Ang UniversitySeoul06974Republic of Korea Nanophotonics Research Center Korea Institute of Science and TechnologySeoul2792Republic of Kora

We synthesized reddish-orange luminescent La_(10)W_(22)O_(81)(LWO):Sm^(3+)microphosphors by hydrothermalassisted solid-state reaction.X-ray diffraction analysis reveals that all the studied phosphors crystallize in an orthorhombic structure in the Pbcn space group(60),Field emission scanning electron microscopy indicates that the LWO:1.5 mol% Sm^(3+)phosphor displays a smooth-surfaced hexagonal rod-lik. shape,with a closed shape at both ends,and high-resolution transmission electron microscopy demonstrates a robust crystalline *** chemical composition and valence states of the phosphor were investigated using X-ray photoelectron *** 403 nm excitation,LWO:1.5 mol% Sm3+exhibits maximum intensity with the strongest band at 596 nm(^(4)G_(5/2)→^(6)H_(7/2)) in the reddish-orange *** intensity of Sm^(3+) emission decreases beyond 1.5 mol% owing to concentration quenching regulated by dipole-quadrupole interaction between Sm^(3+)*** optimized microphosphor LWO:1.5 mol% Sm^(3+)exhibits color coordinates(0.5760,0.4207),which is close to that of the Amber LED-NSPAR 70 BS(0.570,0.420),displaying the highest color purity of 99.2% and correlated color temperature of 1694 *** addition,both breast cancer cells MCF-7 and normal lung fibroblasts WI-38 were tested for toxicity with the optimized *** is found that the LWO:1.5 Sm^(3+)microphosphor is extremely toxic to cancer cells,but not to normal *** on these results,LWO:Sm^(3+)microphosphor can serve as a biomedical candidate for the treatment of cancer,as well as a potential multicolor emitting material for w-LEDs.

关键词： Sm^(3+):La_(10)W_(22)O_(81) Reddish-orangeemission Color purity Photonic applications Anticancer Rareearths

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：