Excess Molar Volume, Viscosity and Heat Capacity for the Binary Mixture of p-Xylene and Acetic Acid at Different Temperatures

Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire range of mole fraction for the binary mixture of p-xylene and acetic acid. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity and excess molar heat capacities were calculated. The values of VE, ηE and cpE were fitted to the Redlich-Kister equation. Good agreements were observed. The excess molar volumes are positive with a large maximum value located in the central concentration range. The excess viscosity has an opposite trend to the excess molar volume VE. ηE values are negative over the entire range of the mixture. The cure of dependence of cpE on concentration has a special shape. The molecular interaction between p-xylene and acetic acid is discussed.     

1,2-丙二醇水溶液在不同温度下的超额摩尔体积黏度和热容

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.     

Density and Excess Molar Volume of Binary Mixtures ofp-Xylene＋Acetic Acid and o-Xylene＋Acetic Acid at Different Temperatures and Pressures

A new apparatus was designed with a thick-walled glass capillary, electric heater tube with red copper and heat preservation. The thick-walled glass capillary was used for its advantages of resistance to acid corrosion and pressure, and ease of observation. The experimental densities over the entire range of mole fraction for the binary mixture of p-xylene＋acetic acid and o-xylene＋acetic acid were measured using the new apparatus at temperatures ranging from 313.15K to 473.15K and pressure ranging from 0.20 to 2,0 MPa. The density values were used in the determination of excess molar volumes, W. The Redlich-Kister equation was used to fit the excess molar volume values, and the coefficients and estimate ot the standard error values were presented. The experimental resuits prove that the density measurement apparatus is successful.     

二元混合物环丁酚和对二甲苯、乙苯在温度范围为303.15—353.15K下的密度、黏度及其相关性质

Densities and viscosities of the binary systems of sulfolane ＋ ethylbenzene, sulfolane ＋ p-xylene have been experimentally determined in temperature interval 303.15—353.15 K and at atmospheric pressure for the whole composition range. The excess molar volumes and viscosity deviations were computed. The computed quantities have been fitted to Redlich-Kister equation. Excess molar volumes and viscosity deviation show a systematic change with increasing temperature. Two mixtures exhibit negative excess volumes with a minimum which occurs approximately at χ = 0.5. The effect of the size, shape and interaction of components on excess molar volumes and viscosity deviations is discussed.     

正癸烷+正戊醇,+1-己醇,+庚醇二元混合物在293.15到363.15K和大气压力下的密度和粘度（英文）

Densities (ρ) and dynamic viscosities (η) for three binary mixtures of n-decane with 1-pentanol, 1-hexanol and 1-heptanol are presented at temperatures from 293.15 to 363.15 K and atmospheric pressure over the entire composition range. The density and viscosity are measured using a vibrating tube densimeter and a cylindrical Couette type rotating viscometer, respectively. Excess molar volumes (VE), viscosity deviations (Δη) and excess Gibbs energy of activation of viscous flow (ΔG*E) are calculated from the experimental measurements. Intermo-lecular and structural interactions are indicated by the sign and magnitude of these properties. Partial molar vol-umes and infinity dilution molar partial volumes are also calculated for each binary system. These results are correlated using Redlich–Kister type equations.     

对二甲苯与环己烷、正庚烷、正辛烷、环丁砜和N-甲基-2-吡咯烷酮和乙酸二元混合物在303．15K和323．15K的超额体积和黏度

Experimental data on density and viscosity at 303.15K and 323.15K are presented for the binary mixtures of p-xylene with cyclohexane, n-heptane, n-octane, sulfolane, N-methyl-2-pyrrolidone and acetic acid. From these data, the excess molar volume and deviations in viscosity have been calculated. The computed quantities have been fitted to the Redlich-Kister Equation to derive coefficients and estimate the standard error values. Results are discussed in terms of intermolecular interactions.     

2-甲基-3-丁烯-2-醇+直链一元醇二元体系的过量摩尔体积和表观摩尔体积298.15 K)

Excess molar volumes (Vm^E) of binary mixtures of 2-methyl-3-buten-2-ol[CH3C(OH)(CH3)CHCH2] with four 1-alcohols:methanol,ethanol,1-propanol and 1-butanol at 298.15K and atmospheric pressure are derived from density measurements with a vibrating-tube densimeter.All the excess volumes are negative in the systems over the entire composition range. The results are correlated with the Redlich-Kister equation.The effects of chain length of 1-alcohols on Vm^E are discussed.The apparent molar volumes of 2-methyl-3-buten-2-ol and 1-alcohols are calculated respectively.     

Excess Molar Volumes and Viscosities of Binary Mixtures of p-Xylene with Cyclohexane, n-Heptane, n-Octane, Sulfolane, N-Methyl-2-pyrrolidone and Acetic Acid at 303.15 K and 323.15 K and Atmospheric Pressure

Experimental data on density and viscosity at 303.15 K and 323.15 K are presented for the binary mixtures of p-xylene with cyclohexane, n-heptane, n-octane, sulfolane, N-methyl-S-pyrrolidone and acetic acid. From these data, the excess molar volume and deviations in viscosity have been calculated. The computed quantities have been fitted to the Redlich-Kister Equation to derive coefficients and estimate the standard error values. Results are discussed in terms of intermolecular interactions.     

乙酸丁酯-芳香烃混合液中声速和超额等熵压缩系数的测定

Speed of sound data for butyl acetate＋benzene, or toluene, or o-xylene, or m-xylene, or p-xylene binary mixtures have been measured over the entire range of mole fraction at 308.15 K. The excess isentropic compressibilities （ Ks^E ） were computed from speed of sound and density data, derived from molar excess volume data. The Ks^E values were analyzed by using graph theoretical approach. The Ks^E values evaluated by graph theory compared reasonably well with their corresponding experimental values. The Ks^E data were also expressed in terms of Redlich-Kister polynomial equation to derive the coefficients and the standard deviation.     

不同温度压力下纯水、醋酸+水、对二甲苯+醋酸+水黏度测定(英文)

The viscosities of pure water, the acetic acid + water binary system, and the p-xylene + acetic acid + water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313.15 to 473.15 K and pressures from 0.10 to 3.20 MPa. The viscosity data were fitted by a correlation equation for the estimation of the mixture viscosities. The average absolute deviations (AAD) of the correlation for binary and ternary systems are 2.48% and 1.77%, respectively.     

Orthophosphates and Diphosphates Containing Zinc and Copper and Zinc and Cobalt

Solid solutions of diphosphates of zinc and copper and of zinc and cobalt were synthesized from mixtures of pure diphosphates at temperatures up to 1000°C. Their X-ray diffractometry patterns varied continuously from one end member to the other. Solid solutions of orthophosphates of composition Zn_3−xCox(PO₄)2, with x = 0.4–1.6, were formed at temperatures up to 950°C; all exhibited the structure of γ-Zn₃(PO₄)2. Solid solutions of orthophosphates of composition Zn_3−xCu_x(PO₄)2 exhibited more-complex behavior. At 1000°C and copper contents of 20–80 mol%, a phase that is related to Cu₃(PO₄)2, termed here the "ε-phase," predominated. At 850°–950°C and in the region from 20 mol% to ∼33 mol% of copper, the solid solutions (the "η-phase") adopted the structure of graftonite. At 800°–900°C and 10–15 mol% of copper, the solid solutions exhibited a new structure (the "δ-phase"), which we found to be related to the mineral sarcopside. At temperatures 950°C, the solutions that contained 5–15 mol% of copper (the "β-phase") had the structure of β-Zn₃(PO₄)2, whereas at 800°–850°C, solutions with 5 mol% of copper (the "-phase") exhibited the structure of γ-Zn₃(PO₄)2. Attempts to synthesize Cu⁺ZnPO₄ and Cu⁺Cu²⁺Zn₃(PO₄)3 were unsuccessful.     

科技创新与钢铁科技进步

建设创新型国家是我们中华民族的历史责任。“自主创新、重点突破、支撑发展、引领未来”的16字方针应当成为我们未来创新活动的指南。建设创新型国家把自主创新放在首位,并提出了引领未来的高标准要求。钢铁科技创新必须突出重点,抓住创新成果产业化这个关键,支撑起行业和国民经济的发展。     

油气管道及储运设施安全保障技术发展现状及展望

相比已经完善丰富的开采和勘探技术,油气的运输以及储存却仍然存在不足之处。我国对能源安全提出更加严格要求的同时,对区域经济的发展规划也有足够重视。因此,保障油气管道的安全则成为了我国能源安全战略的重中之重。在阐释油气管道现阶段在储运安全保障技术发展状况的基础上,分析了现存的问题及解决问题的手段,并指出未来可能使用的目标策略,为今后研究者提供一定程度上的借鉴经验。     

膜的污染和劣化及其防治对策

较为系统地介绍了膜污染和劣化的定义和特点,因膜污染和劣化而造成的膜性能变化,以及如何预防、减少或清除膜污染和劣化的一些通用方法。     

填料-橡胶的化学和物理作用及补强ⅡN330,SiO2,n-SiO2和n-SiO2/KH-846与NR

研究了填料－橡胶的相互作用。发现N330－NR间的相互作用。n－SiO2（粒径：15nm）／KH－846－NR间的相互作用，都是化学作用占优势（＞80％），化学作用对补强的贡献率都大于90％；无偶联剂KH－846时，n－SiO2和SiO2（粒径：15．8nm）与NR都无化学作用，只有物理交联，由于隔离作用，都降低硫化体系与橡胶相互作用的化学交联密度，但n-SiO2的物理交联密度是SiO2的2．6倍，对补强的贡献是SiO2的1．9倍，也是n-SiO2／KH－846体系的61％。     

Crystallography and equilibrium solubility for ammonium and potassium orthophosphites and hypophosphites

The composition and solubility properties of eight ammonium and potassium orthophosphites and hypophosphites were determined to evaluate the potential of these classes of materials for increasing the plant nutrient content of liquid fertilizers. Phase relationships for the systems (NH₄)₂O-P₂O₃-H₂O, K₂O-P₂O₃-H₂O, (NH₄)₂O-P₂O-H₂O, and K₂O-P₂O-H₂O were determined along with the crystallographic properties (X-ray and optical) of the solid phases. Toxicity and phosphite response was tested in greenhouse experiments for the compounds.     

Synthesis and Biological Evaluation of (−) and (+)-Spiroleucettadine and Analogues

A second-generation enantiospecific synthesis of spiroleucettadine is described. The original reported antibacterial activity was not observed when the experiment was repeated on the synthetic samples; however, significant anti-proliferative activity was uncovered for both enantiomers of spiroleucettadine. Comparison of the optical rotational data and ORD-CD spectra of both enantiomers and the reported spectrum from the natural source have not provided a definitive answer regarding the absolute stereochemistry of naturally occurring spiroleucettadine. Efforts then focussed on alteration at the C-4 and C-5 positions of the slightly more active (−)-spiroleucettadine. Ten analogues were synthesised, with three analogues found to possess similar anti-proliferative profiles to spiroleucettadine against the H522 lung cancer cell line.     

VB与Excel数据导入导出的研究与实现

通过引用Excel对象实例和ADO对象,解决VB中的数据与Excel数据导入、导出的问题.     

绿色火炸药及相关技术的发展与应用

综述了绿色火炸药及其生产工艺、销毁以及回收利用方面具有“绿色”特征的改进和应用研究成果。绿色火炸药包括洁净固体推进剂、无铅双基推进剂、TPE发射药、无毒发射药、无铅点火药和起爆药。绿色制造技术包括N2O5作硝化剂的含能硝基化合物化学合成,过硝酸盐作硝化剂、微生物作催化剂的生物合成技术,连续化柔性制造技术,基于双螺杆混合成型火炸药生产技术,火炸药生产中挥发性污染物的安全消除技术和纳米复合含能材料的Sol-Gel制备技术。绿色销毁和回收利用技术包括销毁产品的熔盐氧化技术、摧毁含含能化合物废水的光催化技术以及火炸药的回收再利用（R^3）技术。评述了上述火炸药及相关技术的最新状况和发展方向,附参考文献25篇。     

Tetraalkynylated and Tetraalkenylated Benzenes and Pyridines: Synthesis and Photophysical Properties

Tetra(arylalkynyl)pyridines and tetra(arylalkenyl)pyridines and their benzene analogues were prepared by palladium‐catalyzed cross‐coupling reactions from the commercially available chlorinated substrates in good to excellent yields. The photophysical properties of selected compounds were investigated and compared to each other. Very good fluorescence quantum yields were observed, especially for the pyridine derivatives.