检索结果-南通市图书馆

Noise emission of concrete pavement surfaces produced by diamond grinding

Journal of Traffic and Transportation Engineering(English Edition) 2015年第2期2卷 81-92页

作者： Jens Skarabis Ulrike Stckert Center for building materials Technical University of Munich Federal Highway Research Institute (BASt)

In Germany, diamond grinding is frequently used to improve the evenness and skid resistance of concrete pavement surfaces. Since diamond grinding has been observed to affect tyre/pavement noise emission favourably, the relationship among surface texture, concrete composition and noise emission of concrete pavement surfaces has been sys- tematically investigated. The simulation program SPERoN was used in a parameter study to investigate the main factors which affect noise emission. Based on the results of the simulations, textured concrete surfaces were produced by using a laboratory grinding machine. As well as the composition of the concrete, the thickness and spacing of the diamond blades were varied. The ability of the textured surfaces to reduce noise emission was assessed from the texture characteristics and air flow resistance of textured surfaces measured in the laboratory. It was found that concrete composition and, in particular, the spacing of the blades affected the reduction in noise emission considerably. The noise emission behaviour of numerous road sections was also considered in field investigations. The pavement surfaces had been textured by diamond grinding during the last years or decades. The results show that diamond grinding is able to provide good, durable noise- reducing properties. Several new pavement sections were investigated using thicknesses and spacings of the blades similar to those used in the laboratory to optimize noise emission reduction. It is concluded that diamond grinding is a good alternative to exposed aggregate concrete for the production of low-noise pavement surfaces.

关键词： Concrete pavement Noise emission Diamond grinding Surface 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

Synthesis and property characterization of ternary laminar Zr_(2)SB ceramic

引用

Journal of Advanced Ceramics 2022年第5期11卷 825-833页

作者： Qiqiang ZHANG Shuai FU Detian WAN Yiwang BAO Qingguo FENG Salvatore GRASSO Chunfeng HU Key Laboratory of Advanced Technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Green building materials China Building Materials AcademyBeijing 10000China

In this paper,Zr_(2)SB ceramic with purity of 82.95 wt%(containing 8.96 wt%ZrB_(2)and 8.09 wt%zirconium)and high relative density(99.03%)was successfully synthesized from ZrH_(2),sublimated sulfur,and boron powders by spark plasma sintering(SPS)at 1300℃.The reaction process,microstructure,and physical and mechanical properties of Zr_(2)SB ceramic were systematically *** results show that the optimum molar ratio to synthesize Zr_(2)SB is n(ZrH_(2)):n(S):n(B)=1.4:1.6:*** average grain size of Zr_(2)SB is 12.46μm in length and 5.12μm in width,and the mean grain sizes of ZrB2 and zirconium impurities are about 300 *** terms of physical properties,the measured thermal expansion coefficient(TEC)is 7.64×10^(-6) K^(-1) from room temperature to 1200℃,and the thermal capacity and thermal conductivity at room temperature are 0.39 J·g^(-1)·K^(-1)and 12.01 W·m^(-1)·K^(-1),*** room temperature electrical conductivity of Zr_(2)SB ceramic is measured to be 1.74×10^(6)Ω^(-1)·m^(-1).In terms of mechanical properties,Vickers hardness is 9.86±0.63 GPa under 200 N load,and the measured flexural strength,fracture toughness,and compressive strength are 269±12.7 MPa,3.94±0.63 MPa·m1/2,and 2166.74±291.34 MPa,respectively.

关键词： Zr_(2)SB spark plasma sintering(SPS) reaction path microstructure properties

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

Luminescent property and energy transfer from Ce3＊ to Tb3＋ in YAI3（BO3）4

引用

Optoelectronics Letters 2013年第3期9卷 194-197页

作者： DAI Xiu-hong LI Hong-lian PANG Li-bin GAO Shao-jie college of Physics Science and Technology Hebei University Baoding 071002 China college of Quality & technical Supervision Hebei University Baoding 071002 China Department of Foreign Language Teaching and Research Hebei University Baoding 071002 China

A series of Ce3＋, Tb3＋ or Ce3＋/Tb3＋ doped YA13（BO3）4 phosphors are synthesized by a high temperature solid-state reaction, and their luminescent properties are investigated. YA13（BO3）a：Ce3＋ shows a broad emission band at 422 nm under the 367 nm radiation excitation. YA13（BO3）4：Tb3＋ can be efficiently excited by the ultraviolet （UV） light, and produces green emission. The emission intensity of YA13（BO3）4：Tb3＋ can be enhanced by adjusting Tb3＋ doped content, and reaches the maximum at 0.06 mol Tb3＋. When Ce3＋ is codoped, the emission intensity of Tb3＋ in YA13（BO3）4 can be enhanced, but the commission international del＇eclairage （CIE） chromaticity coordinates of YA13（BO3）4：Tb3＋ have almost no change. Moreover, the energy transfer from Ce3＋ to Tb3＋ in YA13（BO3）4 is studied.

关键词：能量转移发光性能固相反应合成绿光发射发光强度铽掺杂发光特性掺杂含量

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

Improving microstructure and mechanical properties of Ti43Al5Nb0.1B alloy by addition of Fe

引用

Rare Metals 2019年第11期38卷 1024-1032页

作者： Yong Yang Rui-Run Chen Hong-Ze Fang Jing-Jie Guo Hong-Sheng Ding Yan-Qing Su Heng-Zhi Fu School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of materials Engineering Baotou Vocational&Technical CollegeBaotou 014030China

Alloying additions of 0 at%-1.1 at% Fe were added into Ti43A1Nb0.1B alloys for increasing the roomtemperature strength and ductility,and the microstructure and mechanical properties were systematically *** results show that the lattice tetragonality(c/a) of γ phase and the average width of columnar grains of alloys decrease with Fe content *** addition brings about the formation of Fe-rich B2 phase both in the dendrites and in interdendritic regions,and its content increases with Fe contents ***,Fe addition aggravates the Al segregations in the interdendritic *** alloy with 0.7 at% Fe exhibits higher combined mechanical properties with the ultimate compression strength and fracture strain of 1958.4 MPa and 29.8%,*** grain refinement strengthening and solid-solution strengthening of Fe are responsible for the improvement in the strength and the ***,excessive Fe addition results in the decrease in the strength and strain,which is attributed to the severe A1 segregations in the interdendritic regions that cause the premature fracture during compression.

关键词： TiAl Fe B2 phase Microstructure Mechanical properties

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

Study on Kinetics of Natural Rubber Vulcanization by S/La(DiPDP)_3

引用

Journal of Rare Earths 2007年第4期25卷 396-400页

作者：林新花刘清亭陈朝晖王迪珍 college of materials Science and Engineering South China University of Technology Department of Chemical Engineering Guangdong Industry Technical College Guangzhou 510300 China

Kinetics of natural rubber （NR） vulcanization by lanthanum O, O＇-diisopropyldithiophosphate [ La（DiPDP）3 ] was studied. La（DiPDP）3 had remarkable accelerating effect on the vulcanization of NR. The rate constant k6 of the reaction that turned polysulphidic cross-links into the modified main chain was higher than that of desulfuration reaction of polysulfidic cross-links （k3 ）. The activation energies （Ea2, Ea3, and Ea6） of the formation, desulfuration, and decomposition of polysulfidic cross-links were 87.57,102.34, and 95.01 kJ · mol^-1, respectively. Activation energy （Eas） of the reaction that turned the cross-link precursors into the modified main chain was 82.67 kJ · mol^-1. It could be concluded that the proportion of polysulphidic cross-links was higher than mono- and di- sulphidic cross-links during induction and curing periods, mono- and di- sulphidic cross-links increased as curing temperature rose. In the temperature range of 140 - 160 ℃, the amounts of polysulphidic cross-links were similar. However, over 160℃, mono- and di- sulphidic cross-links increased rapidly. Moreover, cross-link density of the vulcanizates was determined from the equilibrium-swelling data. A chemical probe detected the concentration of polysulphidic cross-links of vulcanizates. The change trend of the results predicated from equation corresponded to that of the experimental results.

关键词： vulcanization kinetics natural robber lanthanum O, O'-diisopropyldithiophosphate rare earth accelerator

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

Optimization of the Content of Tricalcium Silicate of High Cementing Clinker

引用

Journal of Wuhan University of Technology(materials Science) 2011年第3期26卷 578-582页

作者：陈琳沈晓冬 State Key Laboratory of materials-oriented Chemical Engineering College of Materials Science and EngineeringNanjing University of Technology Department of Civil Engineering Nanjing Technical Vocational College

Optimization of the content of tricalcium silicate（C 3 S）of high cementing clinker was *** content of free-CaO（f-CaO）,mineral composite,the content of C 3 S in the clinker and the hydration product were analyzed by chemical analysis and X-ray diffraction（XRD）.＂K Value＂method of QXRD was selected as a quantitative analysis way to measure the content of C 3 S,and the strength of cement paste was *** results show that at a water cement ratio of 0.29,the strength of cement paste with 73%C 3 S can be up to 97.5 MPa at 28 days *** strength at 28 d of cement with 73%C 3 S is 16%higher than that with 78%C 3 S at water requirement for normal *** relationship between the strength of high cementing Portland cement and the content of C 3 S in the clinker is *** to the strength of cement paste,the optimal content of C 3 S in cement clinker is around 73%in this paper.

关键词： optimization tricalcium silicate high cementing clinker cement paste

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

Enhanced breakdown strength and energy storage density of AgNbO_(3)ceramics via tape casting

引用

Rare Metals 2023年第2期42卷 495-502页

作者： Ming-Yuan Zhao Jing Wang Lin Chen Hao Yuan Mao-Hua Zhang Su-Wei Zhang Lei Zhao Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of hebei Province College of Physics Science and TechnologyHebei UniversityBaoding071002China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China Department of materials and Earth Sciences Nonmetallic Inorganic MaterialsTechnical University of DarmstadtDarmstadt64287Germany State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China

Antiferroelectric materials are promising candidates for energy-storage applications due to their double hysteresis loops,which can deliver high power *** the antiferroelectric materials,AgNbO_(3)is proved attractive due to its environmental-friendliness and high potential for achieving excellent energy storage ***,the recoverable energy storage density of AgNbO_(3)ceramics is limited by their relatively low breakdown ***,the breakdown strength of the pure AgNbO_(3)ceramics prepared using the tape casting method is enhanced to 307 kV·cm^(-1),which is,to the best of our knowledge,among the highest values reported for pure AgNbO-3bulk *** high breakdown strength may be due to its dense microstructure and good crystallinity obtained by the tape casting method and the optimized sintering *** to its enhanced breakdown strength,AgNbO_(3)ceramics show high recoverable energy storage density of 2.8 J·cm^(-3).These results have led to the development of lead-free antiferroelectric materials and devices with high energy storage density.

关键词： AgNbO_(3) Energy storage performance Antiferroelectric Tape casting

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

Enhanced orange emission by doping CeB_6 in CaAlSiN_3:Ce^(3+) phosphor for application in white LEDs

引用

Journal of Rare Earths 2018年第12期36卷 1250-1255页

作者： Wenjie Wu Kefu Chao Wenquan Liu Lesi Wei Dahai Hu Taiyang Wang O. Tegus college of Physics and Electronic Information Inner Mongolia Normal University Inner Mongolia Key Laboratory for Physics and Chemistry of Functional materials Leshan vocational and technical college

A series of CeB6-doped and CeO2-doped Ca1-xSiAlN3:xCe3+(denoted as CASN:Ce3+@CeB6 and CASN:Ce3+@CeO2, respectively) were synthesized by alloy-nitridation method under high-purity nitrogen atmosphere. The morphologies, crystal phases, and luminescence properties were investigated in *** an increase in the concentration of CeB6, the unit cell volume of CASN:Ce3+@CeB6slightly increases due to the substitution between ions, which leads to a change of micro structure around Ce3+. CASN:Ce3+@CeB6 efficiently emits yellow-orange light with a maximum emission intensity at around 550 nm for the content x of 0.01(being in comparable situation, CASN:Ce3+@CeO2is x = 0.04) when excited at460 nm. Compared with CASN:Ce3+@CeO2, the red emission component of Ce3+ in CASN:Ce3+@CeB6 is much stronger. This is ascribed to energy transfer of intra-Ce3+(within one Ce3+ ion) and inter-Ce3+(between Ce3+ and Ce3+ ions). In addition, the replacements of N3-(0.132 nm for CN = 4) and O2-(0.124 nm for CN = 4) by B2-(0.140 nm for CN = 4), which can lead to a marked expansion of the host lattice and a decrease of the oxidation of samples, are also responsible for the increase of red emission component. Furthermore, CASN:Ce3+@CeB6phosphor has an excellent thermal stability because of the partial substitution of Ce-O(Ce-N) bonds by more covalent Ce-B. As a result, the outstanding luminescent properties of CASN:Ce3+@CeB6 phosphor make it practical to use in the single phosphor-coated high-color-rendering power white LED.

关键词： White LED Nitride CaAlSiN_3:Ce^(3+) CeB_6 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

Self-Assembly of Schiff Base Organogelator with Enhanced Fluorescence Emission

引用

Chinese Journal of Chemistry 2015年第1期33卷 137-140页

作者： Jinxin Han Jiefang Song Zhenfang Hao Haitao Yu Jianrong Han college of Chemistry and Material Science Hebei Normal UniversityShijiazhuangHebei 050024China college of Science Hebei University of Science and TechnologyShijiazhuangHebei 050080China

A new organogelator based on Schiff base derivative has been designed and *** can be employed as building blocks to fabricate organic nano-or *** shows excellent self-assembling *** could form stable gels with nanofiber structures in various organic solvents,such as n-butanol,benzyl alcohol,ethyl acetate,acetone,*** gelation properties,structural characteristics and fluorescence of the gels were *** with the solution,the gel showed significantly enhanced *** organogel system can be used as a thermally driven fluorescence molecular switch.

关键词： organogel Schiff base nanofibers fluorescence

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 grain size on twinning behavior of WE43 magnesium alloy during room-temperature compression deformation

引用

Journal of Rare Earths 2024年第12期42卷 2285-2292页

作者： Lijia Wang Sha Zhan Yutao Ruan Tianhu Miao Li Hu college of Material Science and Engineering Chongqing University of Technology Sichuan Lab of Engineering Aeronautical materials Inspection and Die-forging Technology Sichuan Engineering Technical College

In the present study, room-temperature compression experiments and characterization experiments via optical microstructure(OM), X-ray diffractometer(XRD) and electron backscattered diffraction(EBSD)techniques were conducted on WE43 magnesium(Mg) alloy samples to investigate the grain size effect on twinning behavior. Three couples of solution treatments(823 K for 0.5 h, 798 K for 8 h, 823 K for 16 h,followed by water-quenching at ～333 K) were adopted and these solutionized samples are with different grain sizes of 48.5, 72.0 and 120.2 μm, respectively. Results show that {10-12} extension twin(ET) and {11-21} ET serve as major twinning modes during plastic deformation. For all 7.7%-deformed samples, although the volume fractions of {10-12} ETs and {11-21} ETs increase with the increasing grain size. {10-12} ETs are in growth stage, while {11-21} ETs are mainly in nucleation stage and they still maintain narrow and parallel to each other. Besides, {10-12} ETs mainly contribute to the rotation of caxes of grains towards compression direction, while {11-21} ETs mainly contribute to the formation of a nearly ring-shaped texture component in(0002) pole figure. Twin variants analysis with the assistance of Schmid factor(SF) demonstrates that the activation of twin variants mainly obeys Schmid law. When only {10-12} ETs occur in individual grains, the maximum number of twin variants shows some positive relationship with the increasing grain size. By comparison, when both {10-12} ETs and {11-21} ETs occur in individual grains, the maximum numbers of twin variants are rarely influenced by the increasing grain size.

关键词： WE43 magnesium alloy Grain size effect Microstructure characteristics Twinning behavior 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

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：