期刊文献+
共找到4,545篇文章
< 1 2 228 >
每页显示 20 50 100
钛酸酯催化碳酸二甲酯与苯酚酯交换反应的研究 被引量:28
1
作者 高俊杰 姚洁 +1 位作者 王公应 陆愚 《分子催化》 EI CAS CSCD 北大核心 2001年第1期21-24,共4页
用 Ti(OBu) 4、Ti[OCH(CH3) 2 ]4和 Ti(OPh) 43种钛酸酯作催化剂 ,对碳酸二甲酯 (DMC)与苯酚的酯交换反应进行了研究 .以 Ti(OBu) 4为催化剂 ,对反应的热力学、原料配比、催化剂用量、反应温度和反应时间等工艺条件进行了考察 .实验表... 用 Ti(OBu) 4、Ti[OCH(CH3) 2 ]4和 Ti(OPh) 43种钛酸酯作催化剂 ,对碳酸二甲酯 (DMC)与苯酚的酯交换反应进行了研究 .以 Ti(OBu) 4为催化剂 ,对反应的热力学、原料配比、催化剂用量、反应温度和反应时间等工艺条件进行了考察 .实验表明 ,当 DMC∶苯酚∶ Ti(OBu) 4(摩尔比 ) =1.5∶ 1∶ 0 .0 5、反应温度 175℃、反应时间为 2 5 h时 ,酯交换反应基本上达到平衡 ,苯酚的转化率为 47.4% ,MPC的选择性为 90 .9% ,DPC的选择性为9.14% 展开更多
关键词 钛酸酯 酯交换 苯酯 碳酸二甲酯 碳酸二苯酯 催化剂
原文传递
钛酸盐功能材料的研究与应用 被引量:18
2
作者 冯秀丽 王公应 邱发礼 《化学进展》 SCIE CAS CSCD 北大核心 2005年第6期1019-1027,共9页
本文综述了钛酸盐功能材料的各种性质、合成方法及用途。指出关于新型钛酸盐产品的制备、新性能的发现及寻求新的应用领域是一项值得深入研究的课题。
关键词 钛酸盐 电学性质 光学性质 合成
下载PDF
钛酸盐研究进展 被引量:7
3
作者 杜新瑜 邢欣 +1 位作者 傅圣利 王本根 《材料导报》 EI CAS CSCD 2003年第F09期177-179,共3页
作为一种新型雷达波吸收剂,钛酸盐化合物的研制开发正在国内外展开。介绍了钛酸盐的两种结构钛铁矿类和钙钛矿类,以及在此结构下对应的优越的吸波性能;分析比较了目前较为常见的钛酸盐扮料的合成方法高温气相合成法、共沉淀法和溶胶-凝... 作为一种新型雷达波吸收剂,钛酸盐化合物的研制开发正在国内外展开。介绍了钛酸盐的两种结构钛铁矿类和钙钛矿类,以及在此结构下对应的优越的吸波性能;分析比较了目前较为常见的钛酸盐扮料的合成方法高温气相合成法、共沉淀法和溶胶-凝胶法等,综述了其作为吸波材料应用研究的最新进展。 展开更多
关键词 钛酸盐 高温气相合成法 共沉淀法 溶胶-凝胶法 吸波材料
下载PDF
Investigations on luminescence of rare earths doped CaTiO_3:Pr^(3+) phosphor 被引量:5
4
作者 N. Suriyamurthy B.S. Panigrahi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第4期488-492,共5页
Calcium titanate doped with praseodymium was prepared through solid state reaction and it exhibited intense red emission at 612 nm. Phosphors were characterized for photoluminescence, thermo-luminescence and afterglow... Calcium titanate doped with praseodymium was prepared through solid state reaction and it exhibited intense red emission at 612 nm. Phosphors were characterized for photoluminescence, thermo-luminescence and afterglow emissions. Study of effects of rare earths on photoluminescence as well as afterglow intensity was reported. Presence of gadolinium enhanced luminescence. Presence of some monovalent ions enhanced both afterglow and photoluminescence emission. Thermo-luminescence glow curves were analyzed and ... 展开更多
关键词 perovskites calcium titanates red afterglow rare earths
原文传递
The chance of sodium titanate anode for the practical sodium-ion batteries
5
作者 Feng Chen Haoyu Li +7 位作者 Xianyan Qiao Ruoyang Wang Changyan Hu Ting Chen Yifan Niu Benhe Zhong Zhenguo Wu Xiaodong Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期226-244,共19页
Supporting sustainable green energy systems,there is a big demand gap for grid energy storage.Sodiumion storage,especially sodium-ion batteries(SIBs),have advanced significantly and are now emerging as a feasible alte... Supporting sustainable green energy systems,there is a big demand gap for grid energy storage.Sodiumion storage,especially sodium-ion batteries(SIBs),have advanced significantly and are now emerging as a feasible alternative to the lithium-ion batteries equivalent in large-scale energy storage due to their natural abundance and prospective inexpensive cost.Among various anode materials of SIBs,beneficial properties,such as outstanding stability,great abundance,and environmental friendliness,make sodium titanates(NTOs),one of the most promising anode materials for the rechargeable SIBs.Nevertheless,there are still enormous challenges in application of NTO,owing to its low intrinsic electronic conductivity and collapse of structure.The research on NTOs is still in its infancy;there are few conclusive reviews about the specific function of various modification methods.Herein,we summarize the typical strategies of optimization and analysis the fine structures and fabrication methods of NTO anodes combined with the application of in situ characterization techniques.Our work provides effective guidance for promoting the continuous development,equipping NTOs in safety-critical systems,and lays a foundation for the development of NTO-anode materials in SIBs. 展开更多
关键词 Sodium titanates Sodium-ion batteries Modification methods Electronic materials ELECTROCHEMISTRY Synthesis
下载PDF
蛋白石填充高密度聚乙烯的研究 被引量:5
6
作者 黄海 袁家超 黄锐 《塑料工业》 CAS CSCD 北大核心 2003年第7期14-17,共4页
研究了蛋白石粒径、用量及不同表面处理剂对高密度聚乙烯 (HDPE)填充体系力学性能的影响 ,在相同工艺条件下 ,与碳酸钙填充HDPE进行了对比。结果表明 :经硬脂酸和钛酸酯处理的蛋白石填充HDPE ,在填充量较大 (3 0份 )时 ,材料仍具有良好... 研究了蛋白石粒径、用量及不同表面处理剂对高密度聚乙烯 (HDPE)填充体系力学性能的影响 ,在相同工艺条件下 ,与碳酸钙填充HDPE进行了对比。结果表明 :经硬脂酸和钛酸酯处理的蛋白石填充HDPE ,在填充量较大 (3 0份 )时 ,材料仍具有良好的力学性能 ,且能改善材料的冲击强度 ;且具有比碳酸钙填充体系更好的拉伸性能。 展开更多
关键词 蛋白石 填充 高密度聚乙烯 研究 碳酸钙 硬脂酸 钛酸酯
下载PDF
钛酸盐分子筛的合成研究 被引量:5
7
作者 马淑杰 李连生 +2 位作者 韩春英 裘式纶 郭兴巴图 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1997年第12期1924-1928,共5页
以TPAOH和TEAOH模板剂分别合成了具有孔道结构的钛酸铜、钛铝酸钠和钛酸钠分子筛.采用X射线衍射、红外光谱、紫外光谱、扫描电镜、差热分析、NH3-脱附法及气体吸附法等测试手段对钛酸盐分子筛的物性及结构进行了表征.利用苯酚羟基化... 以TPAOH和TEAOH模板剂分别合成了具有孔道结构的钛酸铜、钛铝酸钠和钛酸钠分子筛.采用X射线衍射、红外光谱、紫外光谱、扫描电镜、差热分析、NH3-脱附法及气体吸附法等测试手段对钛酸盐分子筛的物性及结构进行了表征.利用苯酚羟基化反应及气相色谱法证明了具有四配位TiO4外结构单元的钛酸铜分子筛的催化氧化性能. 展开更多
关键词 钛酸盐 分子筛 水热合成 催化氧化 催化剂
下载PDF
Fabrication,microstructure,and optical properties of nanocrystalline transparent LAST glass ceramics containing CeO_2 被引量:2
8
作者 Mohammad Sadegh Shakeri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第4期401-407,共7页
In the present research, the effect of CeO2 dopant on the fabrication of transparent lithium aluminosilicate titanate (LAST) glass ceramics was investigated. Nanocrystallineβ-quartz solid solution (s.s.) was obse... In the present research, the effect of CeO2 dopant on the fabrication of transparent lithium aluminosilicate titanate (LAST) glass ceramics was investigated. Nanocrystallineβ-quartz solid solution (s.s.) was observed to be the main phase crystallized in this system. Com-parable refractive indices of the glassy matrix andβ-quartz s.s., as well as the incorporation of very fine grains size were determined as the main reasons for retaining the transparency of the glass ceramics. CeO2 was introduced as a suitable optical agent, playing a role as a network modifier in the glass ceramics, because it does not accelerate the growth process and retards the extended growth of crystals. Optical investi-gations indicate that the Fermi energy level, direct and indirect band gaps, and Urbach energy decrease with increasing nanocrystal content in the glassy matrix of specimens, which can be related to the expansion of conduction band, the enhancement of ionic bonds in the crystal lat-tice, and the enhancement of structural arrangement degree, respectively. 展开更多
关键词 glass ceramics NANOCRYSTALS alurninosilicates titanates TRANSPARENCY optical properties
下载PDF
Construction of charge transfer chain in Bi_(12)TiO_(20)-Bi_(4)Ti_(3)O_(12)/α-Bi_(2)O_(3)composites to accelerate photogenerated charge separation
9
作者 Jincheng Yin Xuebing Chen +6 位作者 Guanna Li Dongxu Liu Chun Li Rengui Li Bingxing Xie Johannes H.Bitter Jing Zhang 《Nano Research》 SCIE EI CSCD 2023年第3期3730-3740,共11页
Photogenerated charge separation and transfer is one of the bottleneck steps in photocatalysis,and efficient charge separation strategies are strongly desired.Here,mimicking the electron transport chain in natural pho... Photogenerated charge separation and transfer is one of the bottleneck steps in photocatalysis,and efficient charge separation strategies are strongly desired.Here,mimicking the electron transport chain in natural photosynthesis,we report the design and fabrication of a charge transfer chain using bismuth-based semiconductor as a proof-of-concept.In view of the thermodynamic energy band positions and structural similarity based on the density functional theory(DFT)analysis,heterostructured combination ofα-Bi_(2)O_(3),perovskite-like Bi_(4)Ti_(3)O_(12),and sillenite Bi12TiO20 was designed for fabrication of charge transfer chain.By tuning the molar ratio of Bi and Ti precursors,the Bi_(4)Ti_(3)O_(12)and Bi12TiO20 particles were formed on the surface ofα-Bi_(2)O_(3)by an insitu transformation process,giving rise to Bi_(12)TiO_(20)-Bi_(4)Ti_(3)O_(12)/α-Bi_(2)O_(3)composites with charge transfer chain.We propose that the effective charge transfer is accomplished amongα-Bi_(2)O_(3),Bi12TiO20,and Bi_(4)Ti_(3)O_(12),which significantly improves the photogenerated charge separation and transfer,as indicated by photoluminescene,time-resolved photoluminescene,and electrochemical impedance spectra results.As expected,the Bi_(12)TiO_(20)-Bi_(4)Ti_(3)O_(12)/α-Bi_(2)O_(3)shows the superior photocatalytic activity for the degradation of environmental pollutants with high concentration.Even for the refractory pollutants like 4-chlorophenol,the optimal Bi_(12)TiO_(20)-Bi_(4)Ti_(3)O_(12)/α-Bi_(2)O_(3)composite shows 28 times higher than that ofα-Bi_(2)O_(3)for photocatalytic degradation,verifying the superiority of photogenerated charge transfer chain in photocatalysis.This work demonstrates the feasibility of the charge transfer chain strategy to boost the photogenerated charge separation,which is of great significance for designing energy and environmental-related materials in heterogonous photocatalysis. 展开更多
关键词 photogenerated charge separation charge transfer chain bismuth titanates bismuth oxides
原文传递
N掺杂钛酸盐的电子结构和磁性研究 被引量:3
10
作者 谭兴毅 陈长乐 +1 位作者 金克新 陈鹏 《物理学报》 SCIE EI CAS CSCD 北大核心 2011年第12期453-459,共7页
基于密度泛函理论,从头计算了N掺杂立方结构钛酸盐的电子结构和磁学性质.结果表明,N掺杂钛酸盐在自旋极化状态下的总能量比自旋非极化状态下的总能量小,说明N掺杂钛酸盐的基态具有铁磁性.从态密度和自旋密度分析可知,其磁性源于掺杂的N2... 基于密度泛函理论,从头计算了N掺杂立方结构钛酸盐的电子结构和磁学性质.结果表明,N掺杂钛酸盐在自旋极化状态下的总能量比自旋非极化状态下的总能量小,说明N掺杂钛酸盐的基态具有铁磁性.从态密度和自旋密度分析可知,其磁性源于掺杂的N2p电子和价带顶O2p电子间的p-p耦合作用. 展开更多
关键词 钛酸盐 电子结构 磁学性质
原文传递
Selected aspects of dielectric behavior of plasma sprayed titanates 被引量:3
11
作者 Pavel CTIBOR Josef SEDLACEK 《Journal of Advanced Ceramics》 SCIE CAS 2012年第1期50-59,共10页
XRD measurements were carried out on plasma sprayed titanates BaTiO_(3),CaTiO_(3),MgTiO_(3)and a mixture of the last two.Samples were tested as dielectrics and volume resistivities of the materials were also summarize... XRD measurements were carried out on plasma sprayed titanates BaTiO_(3),CaTiO_(3),MgTiO_(3)and a mixture of the last two.Samples were tested as dielectrics and volume resistivities of the materials were also summarized.Microwave microscopy was used for mapping of the dielectric response of selected samples.The results show differences in the crystal structure between plasma sprayed coatings and feedstock powders in the case of BaTiO_(3)and MgTiO_(3)whereas CaTiO_(3)is crystalograffically identical with its feedstock.The reason can be found in larger sensitivity of BaTiO_(3)and MgTiO_(3)to the reductive conditions at plasma spraying whereas CaTiO_(3)seems to be rather inert from this viewpoint.However CaTiO_(3)exhibits anomalous dielectric losses because of intrinsic conductivity. 展开更多
关键词 plasma spraying dielectric properties electrical properties BaTiO3 and titanates capacitors
原文传递
Artificial solid electrolyte interface layer based on sodium titanate hollow microspheres assembled by nanotubes to stabilize zinc metal electrodes 被引量:2
12
作者 Minfeng Chen Weijun Zhou +4 位作者 Qinghua Tian Xiang Han Yanjun Tan Jizhang Chen Ching-Ping Wong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期539-546,I0015,共9页
Recently,aqueous zinc-ion batteries with intrinsic safety,low cost,and environmental benignity have attracted tremendous research interest.However,zinc dendrites,harmful side reactions,and zinc metal corrosion stand i... Recently,aqueous zinc-ion batteries with intrinsic safety,low cost,and environmental benignity have attracted tremendous research interest.However,zinc dendrites,harmful side reactions,and zinc metal corrosion stand in the way.Herein,we use lepidocrocite-type sodium titanate hollow microspheres assembled by nanotubes to constitute an artificial solid electrolyte interface layer on the zinc metal electrode.Thanks to the hierarchical structure with abundant open voids,negative-charged layered framework,low hydrophilicity,electrically insulting nature,and large ionic conductivity,the sodium titanate coating layer can effectively homogenize the electric field,promote the Zn^(2+)ion transfer,guide the Zn^(2+)ion flux,reduce the desolvation barrier,improve the exchange current density,and accommodate the plated zinc metal.Consequently,this coating layer can effectively suppress zinc dendrites and other unfavorable effects.With this coating layer,the Zn//Zn symmetric cell is able to provide an impressive cumulative zinc plating capacity of 1375 m Ah cm^(-2) at a current density of 5 m A cm^(-2).This coating layer also contributes to significantly improved electrochemical performances of Zn//MnO_(2) battery and zincion hybrid capacitor.This work offers new insights into the modifications of zinc metal electrodes. 展开更多
关键词 Artificial SEI layers Hierarchical sodium titanates Interfacial stability Dendrite inhibition Aqueous Zn-ion batteries
下载PDF
The Effects of Annealing Process on Dielectric and Piezoelectric Properties of BMT-Base Lead-Free Ceramics
13
作者 Mahdi Ghasemifard Meisam Daneshvar Misagh Ghamari 《World Journal of Nano Science and Engineering》 2013年第3期100-107,共8页
By using nitric acid as the fuel, the lead-free ceramic of Ba(Ti1-x,Mgx)O3 (x = 0.31) was prepared by auto combustion method (ACM). To make a comparison, this ceramic was also prepared using mixed oxide method (MOM). ... By using nitric acid as the fuel, the lead-free ceramic of Ba(Ti1-x,Mgx)O3 (x = 0.31) was prepared by auto combustion method (ACM). To make a comparison, this ceramic was also prepared using mixed oxide method (MOM). By X-ray diffraction, the phase structures of two samples were studied, and the results showed that rising temperatures would reduce unwanted phases. The piezoelectric and electrical properties as a function of calcination and sintering temperatures were investigated. The results showed that the outstanding electrical properties were obtained for nanoceramic with this composition. The SEM image of the grain size was estimated around 2 micrometers, and the grain size increased with the increasing of sintering temperature for two samples. The curie temperature of the BMT-ACM was 126°C and it’s significantly larger than the curie temperature of BMT-MOM which was 118°C. The results of electrical properties emphasized that the synthesis optimum temperature for two samples was about 1200°C and it was the best temperature that led to improved properties such as dielectric constant, polarization and piezoelectric coefficients. 展开更多
关键词 DIELECTRIC PROPERTIES BATIO3 and titanates Capacitors
下载PDF
Studies on Enantioselective Effect of Chiral Titanate Reagents on the Synthesis of Substituted Benzhydrols
14
作者 WANG Ji-tao FAN Xiu-ju, FENG Xiao and LI Yue-ming (Department of Chemistry, Nankai University, Tianjin, 300071) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第1期28-34,共7页
Chiral titanate reagents were prepared for inducing asymmetric syntheses of substituted benzhydrols from Grignard reagents and aldehydes. The solvents, reaction temperature and exchange of reactants by crossing experi... Chiral titanate reagents were prepared for inducing asymmetric syntheses of substituted benzhydrols from Grignard reagents and aldehydes. The solvents, reaction temperature and exchange of reactants by crossing experiments were investigated. Favorable attack of the nucleophile upon the aromatic aldehydes' prochiral face was proposed, the absolute configurations of the synthesized benzhydrols were suggested, and a preliminary reaction mechanism was described. 展开更多
关键词 Asymmetric synthesis Benzhydrols Chiral titanates
下载PDF
碱土金属钛酸盐掺杂(K_(0.5)Na_(0.5))NbO_3陶瓷的烧结特性与电学性能 被引量:2
15
作者 陈宏 《中国陶瓷》 CAS CSCD 北大核心 2019年第5期30-36,共7页
采用标准电子陶瓷制备工艺制备了Na_(0.5)K_(0.5)NbO_3陶瓷和高组分碱土金属钛酸盐0.06AETiO_3(AE=Mg、Ca、Sr和Ba)掺杂(K_(0.5)Na_(0.5))NbO_3陶瓷,研究了不同的碱土金属离子对NKN陶瓷的烧结特性和电学性能的影响。研究表明,1130℃烧... 采用标准电子陶瓷制备工艺制备了Na_(0.5)K_(0.5)NbO_3陶瓷和高组分碱土金属钛酸盐0.06AETiO_3(AE=Mg、Ca、Sr和Ba)掺杂(K_(0.5)Na_(0.5))NbO_3陶瓷,研究了不同的碱土金属离子对NKN陶瓷的烧结特性和电学性能的影响。研究表明,1130℃烧结成瓷的NKN-CaT和NKN-SrT陶瓷获得了高的相对密度(>96%);室温下,XRD图谱显示,NKN-CaT、NKN-SrT和NKN-BaT陶瓷均为四方钙钛矿结构;介电温谱显示NKN-CaT、NKN-SrT和NKN-BaT陶瓷的正交-四方相变温度T_(o-t)移到了室温以下;室温下NKN-CaT、NKN-SrT陶瓷表现出了明显的"软"性掺杂的性能,并获得了高的压电系数d_(33)(171 pC/N和135 pC/N)与机电耦合系数k_p(0.275和0.240)。 展开更多
关键词 铌酸钾钠 压电陶瓷 压电性能 钛酸盐
下载PDF
Layered alkali titanates(A_(2)Ti_(n)O_(2n+1)):possible uses for energy/environment issues 被引量:1
16
作者 Taya(Ko)SAOTHAYANUN Thipwipa(Tip)SIRINAKORN Makoto OGAWA 《Frontiers in Energy》 SCIE CSCD 2021年第3期631-655,共25页
Uses of layered alkali titanates(A_(2)Ti_(n)O_(2n+1);Na_(2)Ti_(3)O_(7),K_(2)Ti_(4)O_(9),and Cs_(2)Ti_(5)O_(11))for energy and environmental issues are summarized.Layered alkali titanates of various structural types an... Uses of layered alkali titanates(A_(2)Ti_(n)O_(2n+1);Na_(2)Ti_(3)O_(7),K_(2)Ti_(4)O_(9),and Cs_(2)Ti_(5)O_(11))for energy and environmental issues are summarized.Layered alkali titanates of various structural types and compositions are regarded as a class of nanostructured materials based on titanium oxide frameworks.If compared with commonly known titanium dioxides(anatase and rutile),materials design based on layered alkali titanates is quite versatile due to the unique structure(nanosheet)and morphological characters(anisotropic particle shape).Recent development of various synthetic methods(solid-state reaction,flux method,and hydrothermal reaction)for controlling the particle shape and size of layered alkali titanates are discussed.The ion exchange ability of layered alkali titanate is used for the collection of metal ions from water as well as a way of their functionalization.These possible materials design made layered alkali titanates promising for energy(including catalysis,photocatalysts,and battery)and environmental(metal ion concentration from aqueous environments)applications. 展开更多
关键词 layered alkali titanates photocatalysis hydrogen evdution metal ions collection
原文传递
Atomically Precise Titanium–Oxo Nanotube with Selective Water Adsorption and Semiconductive Behaviors 被引量:1
17
作者 Kalpana Chintakrinda Nagaraju Narayanam +6 位作者 Yan-Zhou Li Fei Wang Chiranjeevulu Kashi Qiao-Hong Li Gang Xu Lei Zhang Jian Zhang 《CCS Chemistry》 CAS 2020年第3期209-215,共7页
We report the first example of carbon nanotube(CNT)-like assembly of the titanium(Ti)framework,Ti oxo inorganic cluster(Ti6O6)hexagonal rings into a titanium oxide(Ti–O)nanotube,prepared by ionothermal synthesis.As d... We report the first example of carbon nanotube(CNT)-like assembly of the titanium(Ti)framework,Ti oxo inorganic cluster(Ti6O6)hexagonal rings into a titanium oxide(Ti–O)nanotube,prepared by ionothermal synthesis.As determined by single-crystal X-ray diffraction analysis,the Ti–O nanotube arrays,stabilized by sulfate ligands,assumed proper parallel alignment with each other and were separated by supramolecular interactions with surrounding EMIm(1-Ethyl-3-methylimidazolium)counter cations.Our stability studies indicated that the Ti–O nanotube obtained is indeed stable in air and various solvents.Also,it could maintain its structure upon heating to∼300°C.Moreover,inside the pores of the Ti–O nanotubes,a rare water molecules nanoconfinement behavior was observed at room temperature.Further,our current developed Ti–O nanotube arrays exhibited selective water adsorption over methanol and ethanol,showing potential applications for miscible solvents separations.Finally,these Ti–O nanotubes demonstrated typical semiconductive characteristics,with the electrical conductivity increasing four orders of magnitude,ranging from 3.15×10^(−10)–1.03×10^(−6)S/cm,as the temperature increased from 35 to 135°C.This work represents a milestone in constructing inorganic Ti–O nanotube arrays with atomically precise structural information for applications as visible-lightinduced photocatalysts,semiconductors,sensors,and optoelectronics. 展开更多
关键词 cluster compounds titanates NANOTUBES atomic structure ionothermal synthesis water adsorption
原文传递
水热法合成钛酸盐(MTiO_3)超细粉体 被引量:1
18
作者 刘春英 柳云骐 +2 位作者 安长华 王淑涛 薛颖 《硅酸盐通报》 CAS CSCD 北大核心 2011年第3期620-624,共5页
本文采用水热法在温和条件下制备出钛酸盐(BaTiO3、PbTiO3、SrTiO3)超细粉体。以Ba(OH)2和钛酸四丁酯为原料,强碱性条件下,水热反应温度150℃、48 h时制备出粒径为20~80 nm的立方相BaTiO3;反应温度为180℃、48 h时制备出粒径为50~80 n... 本文采用水热法在温和条件下制备出钛酸盐(BaTiO3、PbTiO3、SrTiO3)超细粉体。以Ba(OH)2和钛酸四丁酯为原料,强碱性条件下,水热反应温度150℃、48 h时制备出粒径为20~80 nm的立方相BaTiO3;反应温度为180℃、48 h时制备出粒径为50~80 nm的四方相BaTiO3。以钛酸四丁酯和醋酸铅为原料,在180℃、20 h条件下,碱度为c(NaOH)=1.0 mol/L时,制备出粒径在100~130 nm之间的四方相PbTiO3粉体。以钛酸四丁酯和硝酸锶为原料,在180℃、2 h条件下,碱度为c(KOH)=0.2 mol/L时,制备的SrTiO3粉体粒径在40~90 nm之间。通过控制反应条件制得的钛酸盐粉体分散性好、均匀、纯度高。 展开更多
关键词 钛酸盐 水热法 超细粉体
下载PDF
一种杂原子改性钛酸盐热敏电阻材料的制备方法 被引量:1
19
作者 季甲 侯银玲 《凯里学院学报》 2021年第3期34-39,共6页
用非金属元素、金属与非金属共掺杂钛酸盐制备了一系列杂原子改性的钛酸盐热敏电阻材料,并测试了其性能,以便甄选符合工业化生产的制备工艺.结果发现:通过对预烧粉体材料进行扫描电子显微镜(SEM)分析,得出掺入量为0.5%时得到的形貌最佳;... 用非金属元素、金属与非金属共掺杂钛酸盐制备了一系列杂原子改性的钛酸盐热敏电阻材料,并测试了其性能,以便甄选符合工业化生产的制备工艺.结果发现:通过对预烧粉体材料进行扫描电子显微镜(SEM)分析,得出掺入量为0.5%时得到的形貌最佳;1350℃进行烧结居里温度基本达到产品上限,再继续升高温度对提升居里温度效果不明显;随着掺杂量的增大,热敏电阻的阻值数据逐渐上升,0.005 mol为最佳掺杂量,重复性实验平均阻值为50Ω,阻值分布范围较小,数值较集中,符合批量生产要求. 展开更多
关键词 杂原子 钛酸盐 热敏电阻 制备
下载PDF
Selective Oxidation of PM over Li Doped Potassium Titanate Catalysts
20
作者 Meng Xiuhong Gao Yuan +1 位作者 Wang Qiang Duan Linhai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第2期50-54,共5页
K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents (x=0.125, 0.15, 0.3), targeted on removal of two main environmental pollutants: PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and L... K2Ti2O5 and LixK2-xTi2O5 samples with varying K contents (x=0.125, 0.15, 0.3), targeted on removal of two main environmental pollutants: PM and NOx, were synthesized by the solid state method using TiO2, KNO3 and LiOH-H2O as starting materials and were characterized by X-ray diffractometry, scanning electron microscopy, and BET. The catalytic activity of titanate catalysts on PM oxidation was evaluated using the temperature programmed oxidation (TPO) method. The test results showed that the perovskite structure of K2Ti205 was still retained after doping a small amount of Li, and the catalytic performance of LixK2-xTi2O5 had been improved significantly compared with that of K2Ti2O5. Li0.15K1.85Ti205 catalyst had the highest catalytic activity with an ignition temperature of 210℃ and a peak temperature of 290℃. The catalytic activity of both K2Ti2O5 and LixK2-xTi2O5 under intimate contact was higher than that under loose contact. When the exhaust gas flow rate was around 100 mL/min, the catalyst samples showed a highest activity. The Li doped K2Ti2O5 could be an excellent candidate for PM oxidation due to its high oxidation activity, water stability, resistance to sulfur poisoning and economical advantages. 展开更多
关键词 potassium titanates diesel PM PM oxidation Li doping
下载PDF
上一页 1 2 228 下一页 到第
使用帮助 返回顶部