分子的结构与液体的溶解度参数

本文根据Bagley的溶解度参数定义,由修正的Van der Waals模型建立了一个能计算各种温度下液体溶解度参数的公式δ=(RTρm/1-Aρm+Bρm~2)~(1/2)式中ρm是液体的摩尔密度.A和B是两个相关的特性常数,对于一般小分子液体B=0.2610A~2它们都仅与分子的大小有关.本文发展了一种能从分子的结构式准确获得各种液体的特性常数A的基团贡献法,对60种液体的溶解度参数预测结果表明,计算值与实验值的平均相对误差为±0.8%.     

液体饱和蒸气压测定实验数据的处理——Visual FoxPro编程

用静态法测定液体在不同温度下的饱和蒸汽压，可以分别用作图法和计算法求得在所测温度范围内的平均摩尔汽化热。编辑Visual FoxPro程序，用计算机处理数据代替手工处理，求摩尔汽化热和相对误差，这样可以准确快速的对实验数据进行处理，得出实验结果，直观的看出实验的可信度，给实验的数据处理带来很大方便。     

2-甲基-1,3-丙二醇水溶液密度和粘度的测定及关联

常压下采用密度瓶测定了纯液体2-甲基-1,3-丙二醇(MPO)及不同浓度的MPO 水二元体系在298.15~367.15K范围的密度;用乌氏粘度计测定了纯液体MPO及该二元体系在相应温度下的粘度.结果表明:MPO及其水溶液的密度和粘度均随温度升高而减小,密度呈线性衰减,粘度呈指数衰减;一定温度下MPO 水二元体系的密度随浓度变化大约在70%处出现了一极大值. 同时分别由密度和粘度实验数据计算了不同温度及组成下该二元体系的超额摩尔体积V E和混合粘度变化△η,结果V E和△η均为负值, 说明产生了负偏差.并由实验数据拟合出Grunberg-Nissan模型中的MPO-水体系的二元交互参数△Gij,它与温度和组成均有关.     

水与乙醇饱和蒸气压的静态法测定

利用静态法分别测定了纯水及无水乙醇在40～60℃和25～45℃的饱和蒸气压。通过lnp对1/T作图和线性回归,求得了相应温度区间的平均摩尔蒸发焓,对比了实验值与理论值,相对误差分别15.59%与0.49%。表明乙醇更接近真实值,误差较小。而Antoine方程计算对蒸气压数据进行了对比分析,结果表明,纯水的计算值与实验值的平均偏差为12,96%,最大偏差为17.75%。纯乙醇的计算值与实验值的平均偏差为1.1%,最大偏差为3.36%。表明Antoine方程对纯乙醇测量误差更小,更精确。综合可知,乙醇可替代水作为静态法测定液体饱和蒸气压的理想介质。     

TNAZ在乙醇-水二元溶剂中的溶解度

采用动态激光监测技术测定了温度为293.15~323.15K时TNAZ在乙醇-水二元溶剂体系中的溶解度。结果表明,TNAZ在乙醇-水二元溶剂中的溶解度是温度和溶剂比例的函数,溶解度随温度的升高而增大,温度293.15~323.15K时,TNAZ在纯乙醇溶剂中溶解度变化为0.01349~0.03935mol/mol;293.15K,水的摩尔分数0~0.9189时,TNAZ的溶解度变化为0.01349~0.00007mol/mol。实验数据采用Apelblat经验方程(lnx1=a+b/T+clnT)和(CNIBS)/Redlich-Kister方程(lnx1=B0+B1x2+B2x22+B3x23+B4x24)进行关联,关联效果良好(R20.96)。所测定的溶解度数据与关联模型可以作为基础热力学数据和模型在TNAZ结晶生产实践中应用。     

掺杂对巨磁电阻钙钛矿La1-xAx(MnB)O3 Curie温度的影响

测定了La1-xAx(MnB)O3（A为二价元素）型巨磁电阻钙钛矿化合物在不同组成的Curie温度。钙钛矿锰氧化物La1-xAx(MnB)O3的A位离子掺杂引起的晶格畸变可以用晶格能来表示，晶格能的大小能很好解释A位离子掺杂引起的Curie温度变化；B位离子掺杂引起的晶格畸变可用极化力来表示，极化力的大小很好解释了B位离子掺杂引起的Curie温度变化。钙钛矿锰氧化物的A，B位离子同时掺杂引起晶格畸变，可以用晶格能和极化力的综合判断系数（晶格能／极化力）来表示，它能很好解释A和B位离子同时改变引起的Curie温度变化，理论与实验结果一致。     

[Bmim]Cl-xAlCl_3催化合成十二烷基苯

采用AlCl3和[Bmim]Cl不同摩尔比的[Bmim]C1-xA1C13离子液体为催化剂,研究了不同条件下1-十二烯与苯的烷基化反应。实验结果表明,以A1Cl3和[Bmim]Cl的摩尔比为2.0([Bmim]Cl-2A1C13)的离子液体为催化剂,在反应温度25℃、反应时间30 min,苯、烯及离子液体的摩尔比为5︰1︰0.03的条件下,正十二烯的转化率可达98.32%,2-LAB的选择性可达36.76%。离子液体和产物可形成易于分离的双液相,简化了催化剂与产物的分离操作。     

TMPAC-AlCl3离子液体中恒电流电沉积铝

合成了不同TMPAC和AlCl₃摩尔比的TMPAC-AlCl₃离子液体,并测定了其在不同温度下的电导率。在摩尔比为1:2的TMPAC-AlCl₃离子液体中进行了恒电流电沉积实验,研究了温度、电流密度、搅拌速度和添加剂甲苯等对沉积层的影响。结果表明:在相同条件下摩尔比为1:2的TMPAC-AlCl₃离子液体电导率最大,当温度为80℃,电流密度为20 mA·cm^-2,搅拌速度为500 r·min^-1时,沉积层质量较好且电流效率较高;甲苯的加入,增大了TMPAC-2AlCl₃离子液体的电导率,降低了槽电压,当添加甲苯的体积分数为50%,电流密度为23 mA·cm^-2时,可以得到较为致密、色泽良好、平整而均匀的沉积层。     

在水相灵敏测定微量铂的分光光度法研究

研究了在SnCl_2及聚乙烯醇(PVA)存在下用罗丹明B(Rhm B)在水相测定微量铂的高灵敏光度法。其λ_(max)在600 nm处,表观摩尔吸光系数ε_(600)=1.0×10~5l·mol~(-1)·cm~(-1),Pt(Ⅱ)与Rhm B的摩尔比为1:4。重现性、选择性和准确度均好。大多数常见贱金属不干扰,贵金属除锇外均干扰。适合于高纯金属镍中微量铀的分析。     

气流夹带床气化法实验室规模煤反应性试验

为了能在近似地代表气流夹带床气化工艺(例如,Shell煤气化工艺)的条件下,测定含碳物质的气化反应性,已开发了一个比较简单而迅速的微型气化试验。小于100微米的煤粒在几秒钟内被加热到1000—2000℃间的一个预定的温度,然后维持在该温度。气化用CO_2或H_2O进行。试验表明,气化反应性随着煤等级的降低而增加。用CO_2和H_2O进行褐煤、烟煤和液体石油焦的气化反应,在大于1300—1400℃时可能是由扩散来控制的。低于此温度时,用CO_2对褐煤进行的气化反应的活化能约为100千焦耳/摩尔,对烟煤和液体石油焦,活化能约为220—230千焦耳/摩尔。用H_2O气化时,对褐煤的活化能约为100千焦耳/摩尔,对烟煤为290—360千焦耳/摩尔,对液体石油焦为200千焦耳/摩尔。微型气化试验定出的原料相对等级排列和6吨/日装置的结果基本上是一致的。     

Treatment of plasticized PVC to reduce plasticizer/solvent migration: optimization with an experimental design

This work deals with mass transfers between liquid food and PVC packaging. A treatment which reduces the migration both of plasticizer toward a liquid food simulant and the liquid has been investigated. The treatment is a two step process: (1) soaking in a liquid and (2) drying at various temperatures. Some process parameters, such as time and temperature of soaking, temperature and time of drying, influence the treatment efficacy. The best values consider in from these factors were found due to experimental designs and the physical significance of the results is discussed. © 2003 Society of Chemical Industry     

Comparative study on the electrooptical properties of polymer‐dispersed liquid crystal films with different mixtures of monomers and liquid crystals

This article deals with the study of polymer‐dispersed liquid crystal (PDLC) films that consisted of microdroplets of liquid crystals (LCs) dispersed in a polymer matrix. The PDLC films were fabricated by the photoinduced phase separation method under room‐temperature conditions. To determine the extent of the effects of the molecular structures and their physical properties of different mixtures of monomers and LCs on the morphology and electrooptical properties of the PDLC films, various mixtures were used. A detailed discussion of the obtained results is given. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

绿色溶剂-离子液体的合成

室温离子液体作为一类新型的环境友好的“绿色溶剂”,其物理和化学性质相对稳定．具有结构可调及可循环利用等特性,被称为绿色溶剂,已合成的离子液体己达百种以上。文章简述了室温离子液体的种类及离子液体的合成方法。     

An Examination of Surface Tension of Binary Lithium Borate Melts as a Function of Composition and Temperature

Surface tensions of x Li₂O–(1− x )B₂O₃ melts, where 0≤ x ≤0.68, have been measured systematically with a ring method from respective liquidus temperatures up to about 1450 K. For all of the investigated melts, the relationship between surface tension and temperature can be well described by quadratic polynomial functions. With increasing Li₂O content, surface tension monotonously increased, whereas the temperature coefficient of surface tension increased slowly up to about x =0.1, changed sign from positive to negative at about x =0.2, and then remained negative with further increasing Li₂O content. Together with the physical properties reported in our previous work, such as density, temperature coefficient of density, and volume expansion coefficient, etc., both surface tension and temperature coefficient of surface tension have been comparatively plotted as a function of Li/B molar ratio. Differentiated from the inflections of slope in the plots of physical properties vs. Li/B molar ratio, three characteristic regions have been found in the melts of this system. Within different regions, different effects of temperature and concentration on the physical properties of melts have been observed.     

液态饱和水的物性计算

利用线性与非线性最小二乘法,得出液态饱和水的物性对于温度的关系式。据此算出水的物性值与文献中的实验值比较,偏差较小。     

PREFACE SOMER SYMPOSIUM SERIES I

The T method is a newly developed one in distillation calculations which belongs to the class of methods which apply a partitioning of the whole system of equations to be solved

It is similar in nature to the well known B.P. method or theta method, even if, when compared with them, it shows a higher efficiency in reaching the solution

Following the basic ideas of the theta method, the T convergence promoter gives a better estimate of the liquid and vapor molar fractions profiles

As a matter of fact, a better estimate of the temperature profiles, and physical properties is obtained. This situation allows the method to approach the solution by means of quicker convergence

Some explanatory examples will be shown in order to demonstrate the feasibility of the proposed method.     

Drop impact and agglomeration under static powder bed conditions

The influence of impact conditions (reported in terms of Weber and Reynolds numbers) on nucleus formation was studied for single drops striking a static glass bead bed. Results from high speed images showed that the nucleation rate is not influenced by liquid physical properties (density, surface tension, viscosity) for drops that spread significantly (30 < We < 233). Results also showed that nucleus size is determined by how much liquid penetrates into the bed during drop spreading, so does depend on surface tension and liquid density. A corresponding analytical model, derived from first principles, predicts nucleus size to with 1.5% using only liquid physical and powder bed properties, plus the experimentally measured drop spreading behavior. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Chemical–physical properties of bis(perfluoroalkylsulfonyl)imide-based ionic liquids

The chemical–physical properties of hydrophobic ionic liquids, tailored as electrolyte components for supercapacitors and lithium batteries, were investigated and compared. The ionic liquid samples are based on bis(perfluroalkylsulfonyl)imide anions coupled with different types of cation. The effect of the cation as well as the main cationic aliphatic side group, in combination with different anions, on the chemical–physical properties of the investigated ionic liquid samples was evaluated and discussed. The activation energy for the conduction mechanism and the glass transition temperature were obtained by fitting the conductivity vs. temperature data.     

Glycerol and Citric Acid Treatment of Lodgepole Pine

As part of a research program to expand the potential of wood products in exterior applications, lodgepole pine wood was impregnated with a solution of glycerol and citric acid to improve its dimensional stability and other relevant properties. Two catalysts were studied: one liquid (hydrochloric acid, HCl) and one solid (nanoclay, Cloisite 30B). After impregnation, the specimens were polymerized at two temperatures (160°C and 180°C). The nanoclay dispersion and reticulation analysis were performed by XRD and TEM methods. Other analysis methods such as SEM, DSC, TGA, FT-IR were used to characterize the treatment solutions, polymers and treated specimens. The dimensional stability, hardness, adhesion strength and roughness of the specimens were measured and analyzed. Cloisite 30B proved to be a good catalyst, as it contributed to improving the dimensional stability and hardness of the wood while outperforming the HCl catalyst in counteracting the adhesion strength loss attributed to the wood-polymer composite. The polymerization temperature also affected the results. At 180°C, dimensional stability and adhesion strength were higher than at 160°C and the loss of treatment solution was also higher. Impregnating wood with a glycerol ester could drastically improve its physical properties, including dimensional stability and hardness, particularly when Cloisite 30B nanoclay is used as a catalyst.     

Study of impact properties and morphology of 4,4′‐diaminodiphenyl methane cured epoxy resin toughened with acrylate‐based liquid rubbers

Randomized carboxyl poly(2‐ethylhexyl acrylate) (A‐1) and randomized epoxy poly(2‐ethylhexyl acrylate) (B‐1) rubbers were synthesized in the form of liquid rubber by a solution polymerization technique. The liquid rubbers A‐1 and B‐1 were characterized by ¹H NMR and IR spectroscopic analysis, non‐aqueous titration, viscosity measurements and gel permeation chromatography. The liquid rubbers A‐1 (M?_n = 3900 g mol^?1), B‐1 (M?_n = 4100 g mol^?1) and a (1:1) mixture of A‐1 and B‐1 were pre‐reacted with epoxy resin separately and the modified epoxy networks were made by curing with high temperature curing agent. The modified epoxy networks were evaluated by unnotched Izod impact testing. The morphology and toughening behaviour were analysed by scanning electron microscopy. Optimum properties were obtained with the mixture of A‐1 and B‐1. Copyright © 2003 Society of Chemical Industry