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The chance of sodium titanate anode for the practical sodium-ion batteries
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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
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Effect of solvents on the morphology and structure of barium titanate synthesized by a one-step hydrothermal method
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作者 Xiaoxiao Pang Tingting Wang +5 位作者 Bin Liu Xiayue Fan Xiaorui Liu Jing Shen Cheng Zhong Wenbin Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第7期1407-1416,共10页
Tetragonal barium titanate was synthesized from barium hydroxide octahydrate and titanium tetrachloride through a simple one-step hydrothermal method.The effect of different solvents on the crystal structure and morph... Tetragonal barium titanate was synthesized from barium hydroxide octahydrate and titanium tetrachloride through a simple one-step hydrothermal method.The effect of different solvents on the crystal structure and morphology of barium titanate nanoparticles during the hy-drothermal process was investigated.Except for ethylene glycol/water solvent,impurity-free barium titanate was synthesized in pure water,methanol/water,ethanol/water,and isopropyl alcohol/water mixed solvents.Compared with other alcohols,ethanol promotes the formation of a tetragonal structure.In addition,characterization studies confirm that particles synthesized in methanol/water,ethanol/water,and isopropyl al-cohol/water mixed solvents are smaller in size than those synthesized in pure water.In the case of alcohol-containing solvents,the particle size decreases in the order of isopropanol,ethanol,and methanol.Among all the media used in this study,ethanol/water is considered the optimum reaction media for barium titanate with high tetragonality(defined as the ratio of two lattice parameters c and a,c/a=1.0088)and small aver-age particle size(82 nm),which indicates its great application potential in multilayer ceramic capacitors. 展开更多
关键词 barium titanate hydrothermal synthesis TETRAGONALITY solvent effects
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TITAN系统的移植开发及个例应用 被引量:28
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作者 周毓荃 潘留杰 张亚萍 《大气科学学报》 CSCD 北大核心 2009年第6期752-764,共13页
TITAN(thunderstorm identification tracking analysis and nowcasting)是美国国家大气研究中心(NCAR)基于雷达体系开发的风暴识别、跟踪、分析和预报系统。首先深入分析TITAN的结构、基本算法、主要功能、物理量产品及其模块设计和数... TITAN(thunderstorm identification tracking analysis and nowcasting)是美国国家大气研究中心(NCAR)基于雷达体系开发的风暴识别、跟踪、分析和预报系统。首先深入分析TITAN的结构、基本算法、主要功能、物理量产品及其模块设计和数据接口,其次结合我国各类气象数据的特点,开发实现了雷达、卫星、闪电、探空、飞行作业航迹及中尺度模式产品等数据的接入和融合,自主完成对TITAN的移植和多类数据的融合开发。利用移植的TITAN系统,通过一次典型降水个例的分析,展示了TITAN对风暴单体初生、发展演变、分裂合并、风暴体积、持续时间等的追踪分析功能,显示了其强大的雷达数据分析、追踪识别、统计分析及对云降水的内部结构、物理属性变化分析和外推预报的能力。完整移植开发的TITAN系统,将在短时临近预报、中小尺度天气研究、人工影响天气播云条件追踪分析以及催化作业效果检验等方面有着广阔的应用前景。 展开更多
关键词 titan系统 移植开发 个例应用
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Effect of additives on properties of aluminium titanate ceramics 被引量:7
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作者 姜澜 陈晓燕 +1 位作者 韩国明 孟宇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1574-1579,共6页
The influence of some additives on bulk density,phase composition,mechanical strength and thermal shock resistance of aluminium titanate (AT) ceramics was investigated.AT ceramics with different additives of MgO,SiO... The influence of some additives on bulk density,phase composition,mechanical strength and thermal shock resistance of aluminium titanate (AT) ceramics was investigated.AT ceramics with different additives of MgO,SiO2 and Fe2O3 were prepared by reaction sintering.Properties of AT ceramics were tested by using Archimedes,three-point bending and thermal cycling tests.It was found that additives of MgO,SiO2 and Fe2O3 or their compound additives are favorable to reduce the porosities of AT,enhance mechanical strength and thermal shock resistance.The role of additives can be rationalized in terms of promotion of sintering process,formation of new phases and influence on lattice constant c of AT ceramics. 展开更多
关键词 aluminium titanate ceramics ADDITIVE bulk density mechanical properties
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矿业GIS空间数据在TITAN中的组织应用 被引量:9
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作者 吴立新 崔志琳 +1 位作者 刘纯波 陈桂茹 《遥感信息》 CSCD 1999年第3期35-39,共5页
矿业 G I S作为行业 G I S具有行业特色,在对空间数据进行组织时更加注重空间分析的实现和图形与属性的相互查询。文中结合优秀的 G I S软件开发平台 T I T A N,对矿业 G I S中的空间数据进行了组织,其中重点... 矿业 G I S作为行业 G I S具有行业特色,在对空间数据进行组织时更加注重空间分析的实现和图形与属性的相互查询。文中结合优秀的 G I S软件开发平台 T I T A N,对矿业 G I S中的空间数据进行了组织,其中重点讨论了工作区 工程 主题 地物类 地物的总体矿山空间数据组织模式、地物类型在 T I T A N 中的归纳、地物类的面向对象抽象以及主题的初步定义。 展开更多
关键词 GIS 矿业 数据组织 titan 矿山测量
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Titan听力测试平台在新生儿听力筛查及听力诊断中的应用 被引量:3
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作者 欧阳顺林 王金辉 +3 位作者 褚玉敏 卢川 李献清 张林 《中国耳鼻咽喉颅底外科杂志》 CAS 2017年第4期350-352,共3页
目的应用Titan对初筛未通过的听力高危新生儿进行复筛,评价Titan在新生儿听力筛查及听力诊断中的作用。方法对223例(446耳)初筛未通过的听力高危新生儿在出生后第40天左右(前后不超过3 d)应用Titan分别行自动听性脑干反应(automated aud... 目的应用Titan对初筛未通过的听力高危新生儿进行复筛,评价Titan在新生儿听力筛查及听力诊断中的作用。方法对223例(446耳)初筛未通过的听力高危新生儿在出生后第40天左右(前后不超过3 d)应用Titan分别行自动听性脑干反应(automated auditory brainstem response,AABR)、耳声发射(otoacoustic emission,OAE)、声导抗检测;AABR、OAE系统自动判断是否通过,声导抗检测采用1 KHz探测音,鼓室压低于-50 dapa、声顺<0.3 ml认定为异常;统计数据,并分析其结果。结果 AABR复筛通过436耳,复筛通过率为97.76%(436/446),OAE复筛通过348耳,通过率为78.03%(348/446),二者差异有显著性(χ~2=81.59,P<0.05);声导抗检测异常者共81耳,异常率为18.16%(81/446),其中在AABR复筛未通过10耳中存在声导抗检测异常者共1耳,异常率为10%(1/10),OAE复筛未通过98耳中存在声导抗检测异常者共57耳,异常率为58.16%(57/98),二者差异有显著性(χ~2=6.64,P<0.05)。结论 Titan是一款集AABR、OAE、声导抗检测于一体的新型听力检测仪器,应用于新生儿听力筛查可有效降低假阳性率,并能及早评价患儿的中耳功能,鼓室负压、咽鼓管功能不良是新生儿听力筛查假阳性率高的一个重要因素。 展开更多
关键词 titan 新生儿 听力筛查 自动听性脑干反应 耳声发射
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基于TitanImage软件的QuickBird影像融合 被引量:2
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作者 任德智 潘刚 葛立雯 《东北林业大学学报》 CAS CSCD 北大核心 2013年第3期131-134,共4页
基于北京东方泰坦科技股份有限公司研发具有完全自主知识产权的Titan Image7.0遥感图像处理软件平台,对QuickBird标准组合(全色0.61 m+多光谱2.44 m)影像进行像素级融合,探讨Titan Image7.0遥感图像处理平台在影像融合及评价方面的应用... 基于北京东方泰坦科技股份有限公司研发具有完全自主知识产权的Titan Image7.0遥感图像处理软件平台,对QuickBird标准组合(全色0.61 m+多光谱2.44 m)影像进行像素级融合,探讨Titan Image7.0遥感图像处理平台在影像融合及评价方面的应用。结果表明:该软件以友好的全中文界面,在同一平台上以简单的操作过程即可完成影像的融合过程与质量评价指标的求算,不仅有效的避免了跨平台、语言差异等因素带来的操作不便与信息损失,而且丰富的融合算法和质量评价指标,可以完成多种影像数据的融合和质量评价;从QuickBird影像融合与质量评价结果来看,参与融合的4种算法中以Pansharp融合算法最好,其次为小波变换算法,IHS算法、PCA算法融合效果最差,这与前人的研究结果基本一致。因此,可以认为Titan Image7.0软件是一种非常好的遥感影像融合平台。 展开更多
关键词 titan IMAGE QUICKBIRD 影像融合 质量评价
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近红外光Titan治疗面颈部皮肤松弛临床观察 被引量:4
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作者 杨鹏 麦跃 +2 位作者 孙林潮 李娟 鲁东平 《中国美容医学》 CAS 2012年第12期2215-2217,共3页
目的:评价近红外光Titan治疗面颈部皮肤松弛的临床疗效和安全性。方法:选取27例临床面、颈部皮肤轻度松弛患者。采用美国Cutera公司生产的Titan治疗仪进行治疗,共治疗3次,每次间隔4周。由两位医生和患者根据治疗前后照片共同对治疗前后... 目的:评价近红外光Titan治疗面颈部皮肤松弛的临床疗效和安全性。方法:选取27例临床面、颈部皮肤轻度松弛患者。采用美国Cutera公司生产的Titan治疗仪进行治疗,共治疗3次,每次间隔4周。由两位医生和患者根据治疗前后照片共同对治疗前后改善情况进行评价。结果:所有患者均完成治疗,在治疗结束3个月后进行评估,显示结果:10%的患者没有改善,25%的患者轻微改善,27%的患者中度改善,38%的患者良好改善。在治疗6个月后评估显示:12%的患者轻微改善,34%的患者中度改善,54%的患者显著改善。75%的患者表示满意和非常满意。仅治疗后出现轻微红斑,无1例出现严重副反应。结论:近红外光1100~1800nm能有效改善面颈部皮肤松弛,是一种安全、有效,副作用小的非剥脱性面颈部紧肤治疗的新方法。 展开更多
关键词 皮肤松弛 titan 紧肤
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Preparation and electrochemical performance of tantalum-doped lithium titanate as anode material for lithium-ion battery 被引量:3
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作者 胡国荣 张新龙 彭忠东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2248-2253,共6页
The electrochemical performance of Ta-doped Li4Ti5O12 in the form of Li4Ti4.95Ta0.05O12 was characterized.X-ray diffraction(XRD) and scanning electron microscopy(SEM) were employed to characterize the structure an... The electrochemical performance of Ta-doped Li4Ti5O12 in the form of Li4Ti4.95Ta0.05O12 was characterized.X-ray diffraction(XRD) and scanning electron microscopy(SEM) were employed to characterize the structure and morphology of Li4Ti4.95Ta0.05O12.Ta-doping does not change the phase composition and particle morphology,while improves remarkably its cycling stability at high charge/discharge rate.Li4Ti4.95Ta0.05O12 exhibits an excellent rate capability with a reversible capacity of 116.1 mA·h/g at 10C and even 91.0 mA·h/g at 30C.The substitution of Ta for Ti site can enhance the electronic conductivity of Li4Ti5O12 via the generation of mixing Ti4+/Ti3+,which indicates that Li4Ti4.95Ta0.05O12 is a promising candidate material for anodes in lithium-ion battery application. 展开更多
关键词 lithium-ion battery lithium titanate anode material DOPING
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Dielectric properties and phase transitions of La_2O_3- and Sb_2O_3-doped barium strontium titanate ceramics 被引量:3
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作者 张晨 曲远方 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2742-2748,共7页
The dielectric properties and phase transition characteristics of La2O3- and Sb2O3-doped barium strontium titanate ceramics prepared by solid state route were investigated. The microstructure was identified by X-ray d... The dielectric properties and phase transition characteristics of La2O3- and Sb2O3-doped barium strontium titanate ceramics prepared by solid state route were investigated. The microstructure was identified by X-ray diffraction method and scanning electron microscope was also employed to observe the surface morphologies. It is found that (La,Sb)-codoped barium strontium titanate ceramics exhibit typical perovskite structure and the average grain size decreases dramatically with increasing the content of Sb2O3. Both La3+ ions and Sb3+ ions occupy the A-sites in perovskite lattice. The dielectric constant and dielectric loss of barium strontium titanate based ceramics are obviously influenced by La2O3 as well as Sb2O3 addition content. The tetragonal-cubic phase transition of La2O3 modified barium strontium titanate ceramics is of second order and the Curie temperature shifts to lower value with increasing the La2O3 doping content. The phase transition of (La,Sb)-codoped barium strontium titanate ceramics diffuses and the deviation from Curie-Weiss law becomes more obvious with the increase in Sb2O3 concentration. The temperature corresponding to the dielectric constant maximum of (La,Sb)-codoped barium strontium titanate ceramics decreases with increasing the Sb2O3 content, which is attributed to the replacement of host ions by the Sb3+ ions. 展开更多
关键词 barium strontium titanate LA2O3 SB2O3 PEROVSKITE CERAMICS dielectric properties phase transition
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Formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate by adding CaCO3 被引量:4
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作者 Xiao-hui Li Jue Kou +2 位作者 Ti-chang Sun Shi-chao Wu Yong-qiang Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第6期745-753,共9页
The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was investigated.Thermodynamic analysis was employed to show the feasibility of calcium titan... The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was investigated.Thermodynamic analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and Ca CO3 in a reductive atmosphere,where ilmenite is more easily reduced by CO or carbon in the presence of CaCO3.The effects of CaCO3 dosage and reduction temperature on the phase transformation and metallization degree were also investigated in an actual roasting test.Appropriate increase of CaCO3 dosages and reduction temperatures were found to be conducive to the formation of calcium titanate,and the optimum conditions were a CaCO3 dosage of 18 wt%and a reduction temperature of 1400°C.Additionally,scanning electron microscopy–energy dispersive spectrometry(SEM–EDS)analysis shows that calcium titanate produced via the carbothermic reduction of VTC by CaCO3 addition was of higher purity with particle size approximately 50μm.Hence,the separation of calcium titanate and metallic iron will be the focus in the future study. 展开更多
关键词 vanadium titanomagnetite concentrate calcium carbonate carbothermic reduction metallic iron calcium titanate
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Scalable Preparation of SrTiO_3 Submicro-wires from Layered Titanate Nanowires 被引量:1
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作者 TANG Mao-yu JI Tian-hao XIE Jian 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第2期177-180,共4页
SrTiO3 submicro-wires were prepared by the reaction of layered titanatc nanowircs with Sr(OH)2 powder in an autoclave. The wires were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM... SrTiO3 submicro-wires were prepared by the reaction of layered titanatc nanowircs with Sr(OH)2 powder in an autoclave. The wires were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Ultra-violet visible (UV-vis), photoluminescence (PL) and Raman spectroscopy. The XRD measurement shows that the prepared SrTiO3 submicro-wircs hardly have impurity phases. The SEM and TEM images demonstrate that the scalable wires, which need to be processed at the reaction temperature of 180℃ for about 48 hours, are not composed of single crystals. The PL shows that the wire-like SrTiO3 has emission peaks at the wavelengths of 568 and 585 nm. Further, the Raman spectroscopy reveals structural changes in the products through different reaction time. 展开更多
关键词 OXIDE titanate nanowires strontium titanate SrTiO3 wires
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Titan大气中可能生成NH3的几个反应的量子力学计算
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作者 董光兴 贾秀梅 +1 位作者 葛素红 邵菊香 《四川师范大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期320-324,共5页
运用耦合簇理论CCSD方法和全组态CBS-Q理论对文献(P lanet Space Sc i,2003,51:1003-1011.)提出的Titan大气中可能生成NH3的6个链式反应进行了热化学计算和分析.发现:(a)反应(4)-(6)在Ti-tan环境中反应能够正向进行,具有较大的自发反应... 运用耦合簇理论CCSD方法和全组态CBS-Q理论对文献(P lanet Space Sc i,2003,51:1003-1011.)提出的Titan大气中可能生成NH3的6个链式反应进行了热化学计算和分析.发现:(a)反应(4)-(6)在Ti-tan环境中反应能够正向进行,具有较大的自发反应趋势,反应(2)和(3)不具有反应自发性,在低温下自发反应可能性更低;(b)反应(2)的转变温度为955.14 K,高于这个温度反应才有可能正向进行;(c)可以认为这6个链式反应在Titan大气的低温环境中自然合成NH3是不太可能的;(d)耦合簇理论CCSD方法和全组态CBS-Q理论的计算结果相吻合,互相印证了结论的可靠性. 展开更多
关键词 titan 氨气 热化学函数
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Synthesis of platy potassium magnesium titanate and its application in removal of copper ions from aqueous solution
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作者 谭彦妮 宋旎 +5 位作者 刘咏 罗涛 窦玉海 张青 刘倩楠 罗兰兰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期981-990,共10页
Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of spe... Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of specimens were identified by XRD. The morphology and structural information were characterized by SEM and TEM. The adsorption behavior under different conditions was investigated, including different pH values and different initial copper ion concentrations. The results show that the maximum adsorption capacity of Cu(II) ions is 290.697 mg/g, and almost 99.9% of Cu(II) ions can be removed, which is much higher than that of other sorbents reported. The kinetics of KMTO for the adsorption of Cu(II)ions was studied and the best fit can be obtained by the pseudo-second-order model. Adsorption isothermal data can be well interpreted by the Freundlich equation (R2=0.991). In conclusion, this study highlights that KMTO is a potential material for the efficient removal of heavy metal ions in polluted water. It also opens up a new opportunity for the applications of platy KMTO. 展开更多
关键词 potassium magnesium titanate waste water copper ion REMOVAL adsorption kinetics flux method
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在Titan(土卫六)大气中生成环氧乙烷几个可能反应的量子力学计算研究
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作者 葛素红 程新路 杨向东 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第3期538-542,共5页
运用密度泛函方法和Gaussian 3理论,对Coll等人提出的Titan大气中可能生成环氧乙烷的5个反应进行了热化学计算和分析.结果表明:1.所有反应的反应焓变和吉布斯自由能变都小于零,反应都是放热反应,具有较大的自发反应趋势;2.在低温下反应... 运用密度泛函方法和Gaussian 3理论,对Coll等人提出的Titan大气中可能生成环氧乙烷的5个反应进行了热化学计算和分析.结果表明:1.所有反应的反应焓变和吉布斯自由能变都小于零,反应都是放热反应,具有较大的自发反应趋势;2.在低温下反应的平衡常数很大,其数据显示反应在低温下正向进行的自发反应趋势更大.可以认为,在Titan大气的低温环境中自然合成环氧乙烷是很有可能的;3.由密度泛函方法和Gaussian 3理论两种方法的计算结果相吻合,互相印证了结论的可靠性. 展开更多
关键词 titan 环氧乙烷 热化学函数
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New method for measuring high field electrostrictive response of barium titanate/polyurethane elastomer
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作者 陈凡秀 丛羽奇 +2 位作者 林保平 李建清 何小元 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期88-92,共5页
A new method for measuring the characteristic of electrostriction by a digital speckle correlation method (DSCM) is presented. The in-plane displacement is obtained by using the DSCM, and the out-plane displacement ... A new method for measuring the characteristic of electrostriction by a digital speckle correlation method (DSCM) is presented. The in-plane displacement is obtained by using the DSCM, and the out-plane displacement is obtained by the geometrical relation of the triangle theory. In this application, high field electrostrictive strains of barium titanate/polyurethane elastomer composite materials are measured. The electrostrictive strain is evaluated when the application of an electric field is repeated, and then the electrostrictive coefficient of the sample is obtained. To improve the measuring accuracy, the bilinear interpolation of gray value is used to obtain the sub-pixel gray value. The results are compared with those obtained from the surface fitting algorithm. The experimental results demonstrate that the electrostrictive response of polyurethane increases with the introduction of barium titanate into polyurethane. And by using the DSCM, the measurement of the characteristic of electrostriction can be done quickly and accurately. The DSCM provides an effective tool for the evaluation of electrostrictive response. 展开更多
关键词 digital speckle correlation method electrostrictive response barium titanate/polyurethane elastomer composite material electrostrictive strain
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Diffusion coefficient of Ti^4+ in calcium ferrite/calcium titanate diffusion couple 被引量:1
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作者 Wang Wei Hong-rui Yue Xiang-xin Xue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第9期1216-1225,共10页
This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0-120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700℃.The results show that after t... This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0-120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700℃.The results show that after the diffusion reaction occurred,no longitudinal agglomerations were present on the substrate surface on the calcium titanate side.When the diffusion time was increased to 105 min,a net vacancy flow from calcium titanate to calcium ferrite might have occurred,causing the surface of the calcium ferrite substrate to collapse.The thickness of the diffusion layer of the calcium ferrite/calcium titanate system was about 17-48μm,which conforms to the parabolic law of diffusion.The diffusion coefficient and the Ti^4+concentration in the calcium ferrite/calcium titanate system are related.This shows an increase in the diffusion coefficient with the increase of Ti^4+concentration,and the diffusion coefficient value was in the range of 10^−12-10^−11 cm^2·s^−1. 展开更多
关键词 vanadium-titanium sinter diffusion couple calcium ferrite calcium titanate diffusion coefficient
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坡面颗粒流开源软件TITAN2D的改进及应用
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作者 袁礼 刘伟 翟健 《山地学报》 CSCD 北大核心 2016年第3期346-355,共10页
滑坡或崩塌碎屑流的泛滥范围和冲击力可以用颗粒薄层流模型进行数值模拟研究。薄层流模型是将流体力学的质量守恒和动量守恒方程在深度方向平均后所得的近似方程组,因其在分析上的简化而广受重视。近年来基于颗粒薄层流模型(以Savage-Hu... 滑坡或崩塌碎屑流的泛滥范围和冲击力可以用颗粒薄层流模型进行数值模拟研究。薄层流模型是将流体力学的质量守恒和动量守恒方程在深度方向平均后所得的近似方程组,因其在分析上的简化而广受重视。近年来基于颗粒薄层流模型(以Savage-Hutter模型为代表)的模拟研究取得大量进展,但相应的能够模拟自然地形上碎屑流的开源软件尚不多见。2007年美国纽约州立布法罗大学公开了一款结合颗粒薄层流模型和地理信息系统(GIS)的开源软件TITAN2D。在此,将TITAN2D中原来的HLL通量修改为耗散更小的HLLC通量,并增加了颗粒材料的停止准则。通过简单的颗粒堆积物和溃坝问题,验证了软件改进的有效性。进一步,利用中科院科学数据服务平台的DEM数据对重庆武隆鸡尾山滑坡、舟曲泥石流用干颗粒流进行数值模拟。通过调节底面摩擦角可以使计算结果大概反映实际灾害的泛滥范围,表明该软件值得进一步改进与发展。 展开更多
关键词 颗粒崩塌流 Savage-Hutter模型 停止准则 开源软件 titan2D
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Titan大气中可能存在环氧乙烷的红外光谱的理论预测
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作者 董光兴 葛素红 贾秀梅 《河西学院学报》 2006年第5期28-31,共4页
在B3LYP/6-31G理论水平上对环氧乙烷、乙烯和乙醛分子进行了构型优化,计算了三个分子在Titan大气条件下的频率、绘制分子的红外振动光谱.对环氧乙烷分子的红外振动频率进行了理论归属,与Titan大气模拟实验的结论相比较,发现量子化学理... 在B3LYP/6-31G理论水平上对环氧乙烷、乙烯和乙醛分子进行了构型优化,计算了三个分子在Titan大气条件下的频率、绘制分子的红外振动光谱.对环氧乙烷分子的红外振动频率进行了理论归属,与Titan大气模拟实验的结论相比较,发现量子化学理论计算结果与模拟实验结果基本一致,而且,量子化学理论计算结果与环氧乙烷红外光谱的实验值也符合较好.并进一步分析比较了与环氧乙烷分子的红外谱线很相似的乙烯分子的谱带特征和频率归属以及环氧乙烷的异构体乙醛分子的谱带特征和频率归属.结果表明Titan大气中存在环氧乙烷分子的可能性是很大的. 展开更多
关键词 titan 环氧乙烷 红外光谱 大气模拟实验 理论预测 量子化学 土星 太阳系
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析文化观念视角下的Titanic
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作者 杨秀宁 《电影文学》 北大核心 2011年第3期142-143,共2页
从文化观念视角对影片Titanic的解读,有助于观者进一步的思想洗礼。观念是文化结构中最核心的层次,而生命、爱情、文明则是影片向观者传递的几个重要文化观念。本文认为,生命是宝贵的、现实的,不仅属于自己,也属于关心自己的人和自己关... 从文化观念视角对影片Titanic的解读,有助于观者进一步的思想洗礼。观念是文化结构中最核心的层次,而生命、爱情、文明则是影片向观者传递的几个重要文化观念。本文认为,生命是宝贵的、现实的,不仅属于自己,也属于关心自己的人和自己关心的人;真爱是神圣的、朴素的,在点滴生活及患难中见证爱情;文明应反映历史现实并与社会进步相适应,道德、人性与责任、实事求是等文明的实际状况是文明规则与财富、权势和声望等生存规则矛盾的结果。 展开更多
关键词 文化观念 titanIC 生命 爱情 文明
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