检索结果-南通市图书馆

Investigation on MoS_2 and Graphite Coatings and Their Effects on the Tribological Properties of the Radial Spherical Plain Bearings

引用

Chinese Journal of Mechanical Engineering 2016年第4期29卷 844-852页

作者： QIU Ming lu jianjun LI Yingchun LV Guisen School of Mechatronics Engineering Henan University of Science and Technology School of Mechanical Engineering Northwestern Polytechnical University

With constant enlargement of the application areas of the spherical plain bearings,higher quality lubrication of the bearings is *** solve the lubricating problems of spherical plain bearings under high temperature,high vacuum,high speed,heavy loads and strong oxidation conditions,it is urgent for us to develop more excellent self-lubricating *** this paper,the bonded solid lubricant coatings,which use inorganic phosphate as the binder,the mixture of MoS2 and graphite with two different weight proportions as the solid lubricant,are prepared by spraying under three different spray gun *** bonding strength tests on the coatings show that the best spraying pressure is 0.2 MPa and the better mixing proportion of MoS2 to Graphite is 3：*** for the radial spherical plain bearings with steel/steel friction pair,after the coatings are made on the inner ring outer surfaces,the friction coefficient,the wear loss and the friction temperature of the bearings under four oscillating frequencies are investigated by a self-made *** test results,SEM of the worn morphologies and EDS of worn areas show that tribological properties of the bearing are obviously improved by the bonded solid lubricant *** sprayed under the spray gun pressure of 0.2 MPa,the bearings have better anti-friction and anti-wear properties than those sprayed under 0.1 MPa and 0.3 *** as proved from the XPS analysis,between the coating with 3：1 mixing ratio of MoS2 to Graphite and the coating with 1：1 ratio,the former has less oxidation occurred on the surface and therefore has better tribological characteristics than the *** paper provides a reference to developing a new product of the radial spherical plain bearings with high bonding strength,oxidation resistance and abrasion resistance.

关键词： MoS2 and graphite coating spray gun pressure spherical plain bearing friction wear

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

In situ LA-ICP-MS analyses of mica and wolframite from the Maoping tungsten deposit,southern Jiangxi,China

引用

Acta Geochimica 2020年第6期39卷 811-829页

作者： Guanghong Chen Jianfeng Gao jianjun lu Rongqing Zhang State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The Maoping tungsten deposit is located in the Nanling W-Sn metallogenic belt in South *** and quartz vein types of mineralization developed in this *** occurs in the *** is occurs mainly in greisen and wolframite-quartz veins whereas phengite is found in the underground quartz *** granite and greisen,protolithionite,and zinnwaldite are partly replaced by ***-ICP-MS trace element analyses of micas and wolframite are employed to characterize the ore-forming source and evolution of ore forming *** show compositional variation trend in vertical directions with a decrease of W,Sn,Nb,and Ta and an increase of MgO,V,Ni,and *** in greisen has higher Mo,Sn,Nb,Ta,and REEs than those in quartz *** wolframites show similar REE patterns with enrichment of *** in greisen and quartz veins have negative Eu anomalies,while wolframites in quartz veinlet display positive Eu *** of mica and wolframite from different mining levels of the Maoping deposit suggest that the ore-forming fluids are dominated by magmatic hydrothermal fluids in the deep with a slight addition of meteoric water in the *** fractureinduced depressurization and fluid mixing controlled the evolution of ore-forming fluids and possibly lead to the wolframite deposition.

关键词： Mica Wolframite Magmatic-hydrothermal evolution In situ analysis Quartz-vein type W deposit

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

Vibration Reduction Performance of Damping-Enhanced Water-lubricated Bearing Using Fluid-Saturated Perforated Slabs

引用

Chinese Journal of Mechanical Engineering 2020年第6期33卷 218-227页

作者： Yong Jin jianjun lu Wu Ouyang Zhenglin Liu Kunsheng Lao Ministry of Education Key Laboratory of High Performance Ship Technology(Wuhan University of Technology)Wuhan430063China School of Energy and Power Engineering Wuhan University of TechnologyWuhan430063China

As the first link element for the transmission of shaft vibration to the pedestal and even to the hull,water-lubricated bearing plays a key role in suppressing *** the porous structure is considered as one of the main methods for improving the wideband vibration and noise reduction performance of materials in many industrial fields,the studies in the field of water-lubricated bearing remain *** enhance vibration reduction performance,a fluid-saturated perforated slab is designed in this study,and via the establishment of a fluid-solid coupled vibration model,the influence law and impact levels were analyzed and verified by simulation and *** results obtained verified that the total vibration amplitude of damping-enhanced stern bearing in the vertical direction was smaller than that of the normal stern bearing,and the reduction amplitude of the characteristic frequency agreed with the optimal value at approximately 0.1 of the volume fraction of the liquid phase when the solid-fluid phase was rubber–***,the increase in fluid fraction did not enhance the damping effect,instead,it unexpectedly reduced the natural frequency of the raw material *** research indicates that the design of the fluid-saturated perforated slab is effective in reducing the transmission of the vibration amplitude from the shaft,and presents the best volume fraction of the liquid phase.

关键词： Water-lubricated stern bearing Fluid-saturated perforated slabs Fluid-salid coupled vibration model

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

Preparation of porous polyimide microspheres by thermal degradation of block copolymers

引用

Particuology 2014年第3期12卷 63-70页

作者： Li Wang jianjun lu Miaoqing Liu Li Lin Jingjing Li Key Laboratory of Coal Science and Technology Taiyuan University of Technology

A new preparation method has been developed for thermally stable porous polyimide microspheres. Porous polyimide microspheres were prepared using trib]ock copolymers that consisted of a thermally stable polyimide derived from pyromellitic dianhydride/4,4＇-oxydianiline as the continuous phase and a thermally labile polyether as the dispersed phase. Spheres of copolymers were generated in a nonaqueous emulsion and then gradually heated to complete the imidization to form a microphase-separated structure. Subsequently, thermal treatment at a slightly reduced pressure removed the labile blocks and produced pores. Under suitable decomposition conditions, the pore size of the porous polyimide was in the range of 200-400nm.

关键词： Block copolymer sphere Microphase separation Polyimide Porous microsphere Porous polymer

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

Diversity of Mesozoic tin-bearing granites in the Nanling and adjacent regions,South China:Distinctive mineralogical patterns

引用

Science China Earth Sciences 2017年第11期60卷 1909-1919页

作者： WANG RuCheng XIE Lei lu jianjun ZHU JinChu CHEN Jun State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or （topaz-） albite-lepidolite （zinnwaldite） granites, and geochemically correspond to mealuminous and peraluminous types, respectively. Mineralogical studies demonstrate highly distinctive and critical patterns for each type of granites. In mealuminous tin granites amphibole, biotite and perthite are the typical rock-forming mineral association; titanite and magnetite are typical accessory minerals, indicating highjO2 magmatic conditions; cassiterite, biotite and titanite are the principal Sn-bearing minerals; and pure cassiterite has low trace-element contents. However, in peraluminous tin granites zirmwaldite-lepidolite, K-feldspar and albite are typical rock-forming minerals; topaz is a common accessory phase, indicative of high peraluminity of this type of granites; cassiterite is present as a uniquely important tin mineral, typically rich in Nb and Ta. Mineralogical distinction between the two types of tin granites is largely controlled by redox state, volatile content and differentiation of magmatic melts. In oxidized metaluminous granitic melts, Sn4＋ is readily concentrated in Ti-bearing rock-forming and accessory minerals. Such Sn-bearing minerals are typical of oxidized tin granites, and are enriched in granites at the late fractionation stage. In relatively reduced peraluminous granitic melts, Sn2＋ is not readily incorporated into rock-forming and accessory minerals, except for cassiterite at fractionation stage of granite magma, which serves as an indicator of tin mineralization associated with this type of granites. The nature of magma and the geochemical behavior of tin in the two types of granites thus result in the formation of different types of tin deposits. Metaluminous granites host disseminated tin mineralization, and are locally related to deposits

关键词： Metaluminous tin granites Peraluminous granites Mineral assemblages Mineralogical indication of mineralization Nanling and adjacent regions

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

Small-molecule based thermally activated delayed fluorescence materials with dual-emission characteristics

引用

Science China Chemistry 2021年第4期64卷 534-546页

作者： Xuping Li Shen Shen Chenchen Zhang Miaoqing Liu jianjun lu Liangliang Zhu Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Organic thermally activated delayed fluorescence(TADF)emitters have attracted increasing concerns,owing to their atypical photophysical features that can pave the way to the innovative engineering *** cutting-edge type of luminescent molecules,however,most of them only exert a single-wavelength emission from the lowest excited state,according to Kasha’s *** develop their potential applications in multicolor luminescence and multi-functional luminescent probes for biological imaging,researchers have begun to turn their attention to design organic TADF molecules with dual-emission characteristics,by employing an additional fluorescence,phosphorescence,or TADF signal within a single-component *** herein summarized the design principles as well as the luminescence mechanism of organic donor-acceptor TADF compounds with dual-emission characteristics,the superiority of which can cover unique material applications in modern luminescencerelated fields.

关键词： thermally activated delayed fluorescence dual-emission excited states donor-acceptor

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

Ferruginous Microspherules in Bauxite at Maochang, Guizhou Province, China: Products of Microbe-Pyrite Interaction?

引用

Acta Geologica Sinica(English Edition) 2006年第4期80卷 604-609页

作者： ZHOU Yuefei WANG Rucheng lu jianjun LI Yiliang State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 China Astrobiology Group Center for Environmental Biotechnology 10515 Research Drive Suite 300 Knoxville TN 37932 USA

The Maochang bauxite in Guizhou Province is one of the important aluminum ore deposits in southwestern China. Ferruginous spherules, measuring about a few microns across, were found in the transitional layer of the deposit. The EDS and XRD results show that the microspherules are composed mostly of iron （hydr）oxide minerals （goethite） with only weak presence of aluminum and silicon. Occasionally, some pyrite micrograins with dissolved surface are found associated with goethite within the spherules. It is thus suggested that microspherules are linked to pyrite oxidization. It is also thought that microbial activities contribute not only to pyrite oxidization, but also to ball-like assemblage of the iron （hydr）oxides. The mechanism of the formation of ferruginous microspherules is also believed to be important in studying geomicrobiology of bauxite.

关键词： bauxite ferruginous microspherules microbe-pyrite interaction Maochang Guizhou

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

Oxidation and Mineralization of Mn^2＋ Ions Mediated by Pseudomonasputida： Insights from an Experimental Study

引用

Acta Geologica Sinica(English Edition) 2017年第4期91卷 1276-1285页

作者： CHEN Xiaoy lu Xiancai LIU Huan LI Juan XIANG Wanli ZHANG Rui lu jianjun MOE Key Laboratory of Surficial Geochemistry School of Earth Sciences and Engineering Nanjing University Nanjing Jiangsu 210093 China

The formation of manganese oxides in nature is commonly mediated by microorganisms. In this study, the mineralization of biogenic manganese oxidation mediated by Pseudomanas putida has been experimentally investigated by employing various characterization techniques, including SEM, FESEM, TEM, XRD, and STXM-NEXAFS. The results indicate that Mn^2＋ ions can be oxidized into Mn （IV） minerals （birnessite and pyrolusite） and Mn（III） minerals （hausmannite and feitknechtite）, successively. The primary products （birnessite and pyrolusite） further transformed into hausmannite and feitknechtite under Mn^2＋ ion-enriched conditions. However, birnessite and pyrolusite are the end- products of the continuous microbial oxidation processes. These biogenic Mn oxides are poorly crystallized, which provides them with a high potential for usage in environmental restoration of contaminated soils and waters contaminated with heavy metals. The approaches employed in this study will also enrich genesis research of biological oxidation of Mn（II） species in nature.

关键词： Pseudomanasputida Mn^2+ microbial oxidation biomineralization

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

New Nb-Ta Mineralization Age of the Dajishan W-Nb-Ta Deposit in Jiangxi Province,South China

引用

Acta Geologica Sinica(English Edition) 2019年第2期93卷 485-486页

作者： LIU Feng CHE Xudong HU Huan ZHANG Wenlan lu jianjun State Key Laboratory fo r Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University

Objective The Dajishan W-Ta-Nb deposit is located in the junction of southern Jiangxi and Guangdong Provinces(Fig. 1a). This deposit contains about 190, 000 tons of WO3 reserves,belonging to a super-large W deposit. Most W mineralization (mainly wolframite) at Dajishan occurred in quartz veins, with also some disseminated wolframite in the No. 69 granite.

关键词： MS Pb Jiangxi Province South China

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

Pyrite Surface after Thiobacillus ferrooxidans Leaching at 30℃

引用

Acta Geologica Sinica(English Edition) 2006年第3期80卷 451-455页

作者： lu jianjun lu Xiancai WANG Rucheng LI Juan ZHU Changjian GAO Jianfeng Department of Earth Sciences State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing Jiangsu 210093

In order to investigate the effect of Thiobacillusferrooxidans on the oxidation of pyrite, two parallel experiments, which employed H2SO4 solutions and acidic solutions inoculated with ThiobaciUus ferrooxidans, were designed and carried out at 30℃. The initial pH of the two solutions was adjusted to 2.5 by dropwise addition of concentrated sulphuric acid. The surfaces of pyrite before exposure to leaching solutions and after exposure to the H2SO4 solutions and acidic solutions inoculated with Thiobacillus ferrooxidans were observed by scanning electron microscopy （SEM）. There were a variety of erosion patterns by Thiobacillusferrooxidans on the bio-leached pyrite surfaces. A conclusion can be drawn that the oxidation of pyrite might have been caused by erosion of the surfaces. Attachment of the bacteria to pyrite surfaces resulted in erosion pits, leading to the oxidation of pyrite. It is possible that the direct mechanism plays the most important role in the oxidation of pyrite. The changes in iron ion concentrations of both the experimental solutions with time suggest that ThiobaciUus ferrooxidans can enhance greatly the oxidation of pyrite.

关键词： pyrite surface bio-oxidation erosion pattern Thiobacillus ferrooxidans

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：