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摩尔体积预测有机物水的溶解度和辛醇/水分配系数 被引量:18
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作者 王连生 赵元慧 高鸿 《环境化学》 CAS CSCD 北大核心 1992年第1期55-70,共16页
本文回归分析了20种317个固液化合物的摩尔体积和溶解度以及辛醇/水分配系数的相关性,结果表明:溶解度及辛醇/水分配系数和摩尔体积呈良好的线性相关,讨论了回归系数,并用摩尔体积估算了一些有机物的溶解度和辛醇/水分配系数,并和其它... 本文回归分析了20种317个固液化合物的摩尔体积和溶解度以及辛醇/水分配系数的相关性,结果表明:溶解度及辛醇/水分配系数和摩尔体积呈良好的线性相关,讨论了回归系数,并用摩尔体积估算了一些有机物的溶解度和辛醇/水分配系数,并和其它估算方法进行了比较。 展开更多
关键词 溶解度 辛醇 摩尔体积 水质监测
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《计算机在化工中的应用》教学中发散思维能力的培养 被引量:8
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作者 王帅 钟宏 +2 位作者 夏柳荫 刘广义 曹占芳 《广东化工》 CAS 2011年第3期189-191,共3页
将计算机教育融入化工专业教育,已经成为培养新时期化工专业人才的必然要求。以化工热力学中正丁烷摩尔体积的求解为例,讨论了采用Excel、Matlab、MathCAD和Aspen Plus等几种软件解一元高次方程的方法。结果表明,Excel的直接迭代法和单... 将计算机教育融入化工专业教育,已经成为培养新时期化工专业人才的必然要求。以化工热力学中正丁烷摩尔体积的求解为例,讨论了采用Excel、Matlab、MathCAD和Aspen Plus等几种软件解一元高次方程的方法。结果表明,Excel的直接迭代法和单变量求解法、Matlab的fzero函数求解法、MathCAD的root函数求解法和牛顿迭代法以及Aspen Plus的物性分析法计算方便,结果准确,是值得推荐的解法。 展开更多
关键词 摩尔体积 EXCEL Matlab MATHCAD ASPEN PLUS
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基团贡献法预测硅烷及硅氧烷的折射率 被引量:6
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作者 程大海 伍川 +2 位作者 董红 武侠 张引弟 《杭州师范大学学报(自然科学版)》 CAS 2014年第2期113-122,共10页
基于基团贡献法对110种硅烷和硅氧烷分子进行拆分,分别以摩尔折射度和摩尔体积文献计算值与模型预测值之间的最小残差平方和为目标函数,采用最优化组合算法回归得到各官能团的摩尔折射度和摩尔体积,考察了化合物摩尔折射度、摩尔体积和... 基于基团贡献法对110种硅烷和硅氧烷分子进行拆分,分别以摩尔折射度和摩尔体积文献计算值与模型预测值之间的最小残差平方和为目标函数,采用最优化组合算法回归得到各官能团的摩尔折射度和摩尔体积,考察了化合物摩尔折射度、摩尔体积和折射率估算值与文献值之间的偏差,结果表明计算值和文献值接近,确定的各官能团的摩尔折射度和摩尔体积数值可用于有机硅化合物和聚合物折射率的预测和估算. 展开更多
关键词 基团贡献法 摩尔折射度 摩尔体积 折射率 硅烷 硅氧烷
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LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)熔盐及Yb-Ni合金密度特性研究
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作者 彭军军 王旭 +2 位作者 蔡伯清 石忠宁 任如山 《有色金属科学与工程》 CAS 北大核心 2024年第2期189-194,共6页
LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)熔盐体系的密度是电解法制备稀土Yb合金的重要参数。本文采用阿基米德法测量和分析在1173~1573 K温度范围内LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)体系的密度及其变化规律,同时,利用数学模型估测Yb-Ni合... LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)熔盐体系的密度是电解法制备稀土Yb合金的重要参数。本文采用阿基米德法测量和分析在1173~1573 K温度范围内LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)体系的密度及其变化规律,同时,利用数学模型估测Yb-Ni合金密度,分析电解过程中熔盐与合金的分离性,结果表明:在1173~1573 K温度范围内,(LiF-CaF_(2))eut(eut为熔盐体系共晶点)体系与(LiF-YbF_(3))eut体系密度均随温度升高而线性降低,同时,摩尔体积均随温度线性递增;(LiF-YbF_(3))eut体系过剩体积随温度线性递减;在1173~1573 K温度区间和Yb_(2)O_(3)质量分数在0~4%范围内,当Yb_(2)O_(3)含量一定时,(LiF-CaF_(2))eut-Yb_(2)O_(3)和(LiF-YbF_(3))eut-Yb_(2)O_(3)熔盐体系的密度均随温度升高而线性降低,当温度一定时,(LiF-CaF_(2))eut-Yb_(2)O_(3)体系在0≤x(Yb_(2)O_(3))≤2.5%范围内呈线性递增,而((LiF-YbF_(3))eut-Yb_(2)O_(3)体系在0≤x(Yb_(2)O_(3))≤3.5%范围内呈线性递增;Yb-Ni合金的密度要高于LiF-[CaF_(2)/YbF_(3)]-Yb_(2)O_(3)熔盐体系的密度,在电解过程中易于分离。 展开更多
关键词 熔盐 密度 阿基米德法 摩尔体积 过剩体积
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Density and ionic structure of NdF_3-LiF melts 被引量:5
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作者 胡宪伟 王兆文 +3 位作者 高炳亮 石忠宁 刘风国 曹晓舟 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第4期587-590,共4页
NdF3-LiF melts are commonly used in the electrolysis process of metallic neodymium production. Research on the density and ionic structure of the electrolyte is important for its close connection with the electrolysis... NdF3-LiF melts are commonly used in the electrolysis process of metallic neodymium production. Research on the density and ionic structure of the electrolyte is important for its close connection with the electrolysis mechanism and process. In this paper, the density of LiF-NdF3 melts was studied by the Archimedes method. The results showed that the density decreased with increasing temperature and LiF contents. The changing law was discussed and explained in terms of the micro ionic structure of the melts.... 展开更多
关键词 NdF3-LiF melts DENSITY molar volume Nd-F complex ions ionic structure rare earths
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Density of Ni-Al Alloys in Liquid and Solid-Liquid Coexistence State Measured by a Modified Pycnometric Method 被引量:5
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作者 LiangFANG FengXIAO +1 位作者 ZushuLI ZainanTAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第4期405-410,共6页
The density of Ni-AI alloys in both liquid state and solid-liquid coexistence state was measured with a modified pycnometric method. It was found that the density of Ni-AI alloys decreases with increasing temperature ... The density of Ni-AI alloys in both liquid state and solid-liquid coexistence state was measured with a modified pycnometric method. It was found that the density of Ni-AI alloys decreases with increasing temperature and Al concentration in the alloys. The molar volume of liquid Ni-AI binary alloys increases with the increase of temperature and Al concentration. The partial molar volume of Al in Ni-AI binary alloy was calculated approximately. The molar volume of liquid Ni-AI alloy determined in the present work shows a negative deviation from the ideal linear molar volume. 展开更多
关键词 Ni-Al alloy DENSITY Modified pycnometric method molar volume ALUMINUM
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用改良静滴法测量液态 Ni-W 二元合金的密度(英文) 被引量:6
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作者 方亮 肖锋 陶再南 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2004年第12期1261-1265,共5页
为了给研究合金在凝固过程中发生收缩、迁移现象和偏析提供科学依据,我们用改良静滴法对钨浓度为 0 到 15%的液态Ni-W 二元合金的密度进行了测量。结果表明:Ni-W 二元合金的液态密度随温度的增加而减少,但随合金中钨浓度的增加而增加;液... 为了给研究合金在凝固过程中发生收缩、迁移现象和偏析提供科学依据,我们用改良静滴法对钨浓度为 0 到 15%的液态Ni-W 二元合金的密度进行了测量。结果表明:Ni-W 二元合金的液态密度随温度的增加而减少,但随合金中钨浓度的增加而增加;液态 Ni-W 二元合金的摩尔体积随温度和合金中钨浓度的增加而增加。金属钨在 Ni-W 二元合金中的偏摩尔体积约为(10.80–1.35×10–3T)×10-6m3·mol-1。 展开更多
关键词 Ni—W合金 密度 改良静滴法 摩尔体积
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摩尔比对MMOS水泥力学性能和变形行为的影响及机理
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作者 巴明芳 马哲洋 +2 位作者 纪璐鑫 崔嘉铭 柳俊哲 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第8期733-743,共11页
研究了原材料摩尔比(n(MgO)∶n(MgSO_(4))∶n(H_(2)O))对改性硫氧镁(MMOS)水泥力学性能和变形行为的影响,并采用X射线衍射仪(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)及热重分析(TG)等测试技术对其机理进行分析.结果表明:MMOS水... 研究了原材料摩尔比(n(MgO)∶n(MgSO_(4))∶n(H_(2)O))对改性硫氧镁(MMOS)水泥力学性能和变形行为的影响,并采用X射线衍射仪(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)及热重分析(TG)等测试技术对其机理进行分析.结果表明:MMOS水泥的抗压强度和抗折强度随着水硫比和氧硫比的提高均呈提升趋势.其中原材料摩尔比为10∶1∶12时,水泥力学性能最优.不同摩尔比MMOS水泥在56d龄期内均呈膨胀变形,其中总变形随水硫比和氧硫比的提高呈减小趋势;自收缩变形随水硫比的提高而减小,随氧硫比的提高呈先增后减趋势.这主要是由于硬化后不同摩尔比MMOS水泥中的水化产物Mg(OH)_(2)和5·1·7相(5Mg(OH)_(2)·MgSO_(4)·7H_(2)O)含量各有不同.当Mg(OH)_(2)含量减少,而5·1·7相含量增加时,MMOS水泥的膨胀变形量降低,同时其抗折强度和抗压强度有所提升. 展开更多
关键词 摩尔比 改性硫氧镁水泥 力学性能 体积变形 机理分析
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Excess Molar Volume, Viscosity and Heat Capacity for the Mixture of 1,2-Propanediol-Water at Different Temperatures 被引量:5
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作者 杨长生 马沛生 +1 位作者 唐多强 靳凤民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期175-180,共6页
Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the... Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity was investigated. The values of VE and E were fitted to the Redlich-Kister equation. Good agreement was observed. The excess volumes are negative over the entire range of composition. They show an U-shaped-concentration dependence and decrease in absolute values with increase of temperature. Values of E are negative over the entire range of the composition, and has a trend very similar to that of VE . The analysis shows that at any temperature the specific heat of mixture is a linear function of the composition as x1 > 20%. All the extended lines intersect at one point. An empirical equation is obtained to calculate the specific heat to mixture at any composition and temperature in the experimental range. 展开更多
关键词 VISCOSITY heat capacity DENSITY excess molar volume molecular interaction
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用改良密度法精密测量熔融Ni-Ta二元合金的液态密度(英文) 被引量:6
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作者 方亮 肖锋 +2 位作者 陶再南 汪立文 向井楠宏 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2005年第4期521-525,共5页
用改良密度法对熔融Ni-Ta 二元合金的液态密度进行了精密测量。结果表明:熔融Ni-Ta 二元合金的密度随温度的增加而减少,但随合金中钽浓度的增加而增加;熔融Ni-Ta 二元合金的摩尔体积随温度和合金中钽浓度的增加而增加,并对钽在熔融Ni-T... 用改良密度法对熔融Ni-Ta 二元合金的液态密度进行了精密测量。结果表明:熔融Ni-Ta 二元合金的密度随温度的增加而减少,但随合金中钽浓度的增加而增加;熔融Ni-Ta 二元合金的摩尔体积随温度和合金中钽浓度的增加而增加,并对钽在熔融Ni-Ta二元合金中的偏摩尔体积进行了计算。 展开更多
关键词 Ni—Ta合金 密度 改良密度 摩尔体积
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Model for Evaluating Density of Molten Slag With Optical Basicity 被引量:4
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作者 ZHANG Guo-hua CHOU Kuo-chih 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2010年第4期1-4,共4页
A new model is proposed to estimate the density of molten slag, in which the temperature dependence of density is described by Arrhenius Law with the activation energy expressed as the linear function of optical basic... A new model is proposed to estimate the density of molten slag, in which the temperature dependence of density is described by Arrhenius Law with the activation energy expressed as the linear function of optical basicity. Successful applications to the density calculations of CaO-Al2 O3-SiO2 and Al2 O3-CaO-MgO-SiO2 slag systems show that this formula can give a good description of composition and temperature dependence of density for molten slags. It is also found that the ionic band percentage of M-O band in MOx oxide is the intrinsic origin of the phenomenon that the slag with a high optical basicity has a large sensitivity to temperature. 展开更多
关键词 DENSITY Arrhenius Law optical basicity molar volume ionic band
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Density of Liquid Ni-Mo Alloys Measured by a Modified Sessile Drop Method 被引量:4
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作者 LiangFANG ZushuLI +1 位作者 ZaiNanTAO FengXIAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期287-292,共6页
The density of liquid binary Ni-Mo alloys with molybdenum concentration from 0 to 20% (mass fraction) wasmeasured by a modified sessile drop method. It has been found that the density of the liquid Ni-Mo alloys decrea... The density of liquid binary Ni-Mo alloys with molybdenum concentration from 0 to 20% (mass fraction) wasmeasured by a modified sessile drop method. It has been found that the density of the liquid Ni-Mo alloys decreaseswith increasing temperature, but increases with the increase of molybdenum concentration in the alloys. The molarvolume of liquid Ni-Mo binary alloys increases with the increase of temperature and molybdenum concentration. Thepartial molar volume of molybdenum in Ni-Mo binary alloy has been approximately calculated as [13.18-2.65×10^(-3)T+(-47.94+3.10×10^(-2)T)×10^(-2)X_(Mo)]×10^(-6)m^3·mol^(-1). The molar volume of Ni-Mo alloy determined inthe present work shows a negative deviation from the ideal linear mixing molar volume. 展开更多
关键词 Ni-Mo alloy Densityv Modified sessile drop method molar volume MOLYBDENUM
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Al-Si合金的成分和其凝固收缩率与摩尔体积的关系 被引量:5
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作者 李少博 坚增运 +2 位作者 许军锋 朱满 党博 《铸造》 CAS CSCD 北大核心 2015年第7期609-614,共6页
依据阿基米德原理,通过测量合金在熔盐中所受浮力,对不同硅含量铝硅合金的凝固收缩率、液相的摩尔体积及Al在铝硅合金中的偏摩尔体积进行了研究。结果发现:铝硅合金的凝固收缩率随着硅含量的增大而减小;硅含量超过25%后,铝硅合金凝固后... 依据阿基米德原理,通过测量合金在熔盐中所受浮力,对不同硅含量铝硅合金的凝固收缩率、液相的摩尔体积及Al在铝硅合金中的偏摩尔体积进行了研究。结果发现:铝硅合金的凝固收缩率随着硅含量的增大而减小;硅含量超过25%后,铝硅合金凝固后表现为体积膨胀;当合金硅含量在12.6%至25%之间时,不同铝硅合金在各自液相线温度下熔体的摩尔体积和在754℃下熔体的摩尔体积均随硅含量的增大而减小,当合金硅含量由25%增大至30%时,上述两种摩尔体积均随硅含量的增大而增大;随着硅含量由12.6%增大至25%,754℃时Al在不同硅含量铝硅合金熔体中的偏摩尔体积增大。 展开更多
关键词 AI-Si合金 凝固收缩率 熔盐 摩尔体积
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碳酸铝铵热解制备纳米氧化铝以及陶瓷烧结 被引量:1
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作者 马佳进 罗钱 +3 位作者 李晨辉 胡梁 周念莺 邹阳 《化学与生物工程》 CAS 2023年第11期12-19,共8页
以NH_(4)HCO_(3)和NH_(4)Al(SO_(4))_(2)为原料,采用沉淀法合成了前驱体碳酸铝铵(AACH),再经热解得到氧化铝粉体,系统研究了热解温度、干燥方式、NH_(4)HCO_(3)与NH_(4)Al(SO_(4))_(2)物质的量比对前驱体AACH和热解产物氧化铝的影响。... 以NH_(4)HCO_(3)和NH_(4)Al(SO_(4))_(2)为原料,采用沉淀法合成了前驱体碳酸铝铵(AACH),再经热解得到氧化铝粉体,系统研究了热解温度、干燥方式、NH_(4)HCO_(3)与NH_(4)Al(SO_(4))_(2)物质的量比对前驱体AACH和热解产物氧化铝的影响。结果表明,在NH_(4)HCO_(3)与NH_(4)Al(SO_(4))_(2)物质的量比为10∶1、无水乙醇置换水干燥AACH、热解温度为1025℃的条件下,可以得到粒径约50 nm、比表面积93.23 m^(2)·g^(-1)、分散性较好的纳米氧化铝粉体。当纳米氧化铝粉体中掺入2.0%TiO_(2)时,在含8%H_(2)的N_(2)气氛下1550℃烧结2 h,可以得到相对密度97.40%、体积电阻率3.47×10^(9)Ω·cm的氧化铝陶瓷。 展开更多
关键词 碳酸铝铵 氧化铝 物质的量比 热解温度 干燥方式 体积电阻率
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Density, Viscosity, and Excess Properties for Binary Mixture of Diethylene Glycol Monoethyl Ether + Water from 293.15 to 333.15 K at Atmospheric Pressure 被引量:5
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作者 李新学 徐国民 +1 位作者 王彦伟 胡一江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期1009-1013,共5页
Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O(CH2)2O(CH2)2OH] + water from 293.15 to 333.15 K at atmospheric pressur... Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O(CH2)2O(CH2)2OH] + water from 293.15 to 333.15 K at atmospheric pressure, with a capillary pycnometer and Ubbelohde capillary viscometer respectively. From the experimental data, the excess molar volume V^E, viscosity deviation △η, and the excess energy of activation for viscous flow △G^*E were calculated. These data were correlated by the Redlich-Kister type equations to obtain the coefficients and standard deviations. The results showed a strong molecular interaction between diethylene glycol monoethyl ether and water. 展开更多
关键词 DENSITY VISCOSITY diethylene glycol monoethyl ether binary mixture excess molar volume viscosity deviation
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Density and Structure Analysis of Molten Ni-W Alloys 被引量:3
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作者 FengXIAO LiangFANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第4期410-413,共4页
Density of molten Ni and Ni-W alloys was measured in the temperature range of 1773-1873 K with a sessile drop method. The density of molten Ni and Ni-W alloys trends to decrease with increasing temperature. The densit... Density of molten Ni and Ni-W alloys was measured in the temperature range of 1773-1873 K with a sessile drop method. The density of molten Ni and Ni-W alloys trends to decrease with increasing temperature. The density and molar volume of the alloys trend to increase with increasing W concentration in the alloys. The calculation result shows an ideal mixing of Ni-W alloys. 展开更多
关键词 DENSITY molar volume Ni-W alloys STRUCTURE
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Improved method to determine the molar volume and compositions of the NaCl-H_2O-CO_2 system inclusion 被引量:3
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作者 SONG YuCai1, HU WenXuan1, NI Pei1, DUAN ZhenHao2 & ZHANG XueFeng1 1 State Key Laboratory of Mineral Deposit Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 《Science China Earth Sciences》 SCIE EI CAS 2007年第3期385-391,共7页
On the basis of Parry’s method (1986), an improved method was established to determine the molar volume (Vm) and compositions (X) of the NaCl-H2O-CO2 (NHC) system inclusion. To use this method, the determination of V... On the basis of Parry’s method (1986), an improved method was established to determine the molar volume (Vm) and compositions (X) of the NaCl-H2O-CO2 (NHC) system inclusion. To use this method, the determination of Vm-X only requires three microthermometric data of a NHC inclusion: partial homog-enization temperature (Th ,CO2), salinity (S) and total homogenization temperature (Th). Theoretically, four associated equations are needed containing four unknown parameters: X CO2, XNaCl, Vm and F (volume fraction of CO2 phase in total inclusion when occurring partial homogenization). When they are released, the Vm-X are determined. The former three equations, only correlated with Th ,CO2, S and F, have simplified expressions:XCO2=f1(Th,CO2,S,F),XNaCl=f2(Th,CO2,S,F),Vm=f3(Th,CO2,S,F). The last one is the thermodynamic relationship of X CO2, XNaCl, Vm and Th:f4(XCO2,XNaCl,Vm,Th)=0.Since the above four associated equations are complicated, it is necessary to adopt iterative technique to release them. The technique can be described by:(i) Freely input a F value (0≤F≤1),with Th ,CO2 and S, into the former three equations. As a result,X CO 2,XNaCl and the molar volume value recorded as Vm1 are derived. (ii) Input the X CO2 and XNaCl gotten in the step above into the last equation, and another molar volume value recorded as Vm2 is determined. (iii) If Vm1 is unequal to Vm2, the calculation will be restarted from “(i)”. The iteration is completed until Vm1 is equal to Vm2, which means that the four associated equations are released. Compared to Parry’s (1986) solution method, the improved method is more convenient to use, as well as more accurate to determine X CO 2. It is available for a NHC inlusion whose partial homogenization temperature is higher than clatherate melting temperature and there are no solid salt crystals in the inclusion at parital homogenization. 展开更多
关键词 NaCl-H2O-CO2 SYSTEM INCLUSION molar volume COMPOSITIONS improved EQUATIONS
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Studies on Lattice Parameter,Molar Volume and Excess Molar Volume of Pb-based a-phase Solid Solution in Pb-Sn-Cd Ternary System
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作者 Liu Hengli (Department of Rock Chemistry, Changchun University of Earth Science, Changchun)Long Xiang, Kang Hongye and Zhao Muyu (Department of Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期300-306,共7页
The lattice parameters a and the molar volumes Km of Pb-based a-phase solid solutions in the Pb-Sn-Cd ternary system were determined by means of X-ray diffraction. The lattice parameters a vary linearly with the molar... The lattice parameters a and the molar volumes Km of Pb-based a-phase solid solutions in the Pb-Sn-Cd ternary system were determined by means of X-ray diffraction. The lattice parameters a vary linearly with the molar fractions, the molar volumes show a positive deviation from the ideal solution behaviour, and the contribution of the solute Cd to the excess molar volumes V is much larger than that of the solute Sn. According to Vegard' s law orsub-regular solution model, the relationship between the experimental data of a or Vm andthe compositions of alloy is obtained by the mathematic regressive method, the prediction precisions of the both formulae are within the limits of experiment error. 展开更多
关键词 Alloy solid solution Lattice parameter molar volume Excess molar volume
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Volumetric and Viscometric Studies of 4-Aminobutyric Acid in Aqueous Solutions of Salbutamol Sulphate at 308.15, 313.15 and 318.15K 被引量:4
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作者 K. Rajagopal S.S. Jayabalakrishnan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期796-804,共9页
Density (ρ) and viscosity (η) measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of dens... Density (ρ) and viscosity (η) measurements were carried out for 4-aminobutyric acid in 0.0041,0.0125 and 0.0207 mol·L-1 aqueous salbutamol sulphate at T=308.15,313.15 and 318.15K.The measured values of density and viscosity were used to estimate some important parameters such as apparent molar volume Vφ,limiting apparent molar volume Vφ0,transfer volume △Vφ0,hydration number Hn,second derivative of infinite dilution of partial molar volume with temperature 2Vφ0/T2,viscosity B-coefficients,variation of B with temperature dB/dT,free energy of activation per mole of solvent △μ10* and solute △μ20*,activation entropy △S20* and activation enthalpy △H20* of the amino acids.These parameters have been interpreted in terms of solute-solute and solute-solvent interactions and structure making/breaking ability of solutes in the given solution. 展开更多
关键词 DENSITY standard partial molar volume hydration ntnZnber relative viscosity B-COEFFICIENT activation parameters
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钢坯高温防氧化涂层的热力学性质分析
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作者 段东江 张贵杰 李海英 《河北冶金》 2023年第9期36-41,共6页
介绍了钢坯高温防氧化涂层国内外研究现状及发展趋势。通过Thermo-Calc热力学软件对表面喷涂高温防氧化涂料的钢坯加热过程进行模拟,对体系的初始条件进行设定,确定加热温度范围为25~1 500℃,计算得到体系的摩尔体积、密度以及比热容,... 介绍了钢坯高温防氧化涂层国内外研究现状及发展趋势。通过Thermo-Calc热力学软件对表面喷涂高温防氧化涂料的钢坯加热过程进行模拟,对体系的初始条件进行设定,确定加热温度范围为25~1 500℃,计算得到体系的摩尔体积、密度以及比热容,通过绘图软件绘制图像并进行数据拟合分析,得到涂层的热力学性质随温度的变化规律。结果表明,涂层体系的摩尔体积大致随着温度的升高而增大,也就是发生体积的膨胀,但升高到一定温度后可能会发生收缩,继续升温,体积接着膨胀;体系的密度大致随着温度的升高而减小,但升高到一定温度后可能会发生回升,继续升温,体系的密度又继续减小;体系的比热容随着温度的升高而增大,但存在转变区间,其中出现的折点、拐点、转变区间等代表着涂层质量及热力学性质的变化,对涂层材料的研发设计具有指导作用。 展开更多
关键词 防氧化涂层 摩尔体积 密度 比热容 加热温度 THERMO-CALC
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