阳、阴、非离子表面活性剂胶束对酯碱性水解的影响

应用紫外分光光度法和热动力学方法研究了芳香酸酯和正脂肪酸酯在表面活性剂ＤＴＡＢ、ＴＴＡＢ、ＣＴＡＢ、ＳＤＳ、Ｂｒｉｊ３５、ＴｒｉｔｏｎＸ－１００胶束中的碱性水解反应。阳、阴、非离子表面活性剂胶束对酯的碱性水解均有禁阻作用。讨论了胶束对酯碱性水解禁阻作用的原因。     

阳,阴,非离子表面活性剂胶束对酯碱性水解的影响

应用紫外分光光度法和热动力学方法研究了芳香酸酯和正脂肪酸酯在表面活性剂ＤＴＡＢ、ＴＴＡＢ、ＣＴＡＢ、ＳＤＳ、Ｂｒｉｊ３５、Ｔｒｉｔｏｎ Ｘ－１００胶束中的碱性水解反应，阳、阴、非离子表面活性剂胶束对酯的碱必水解均有禁阻作用，讨论了胶束对酯碱性水解禁阻作用的原因。     

胶束体系中光敏聚合的研究 Ⅵ．水溶性高分子／表面活性剂复合体系中光敏聚合反应

研究了水溶性高分子与三种表现活性剂组成的复合作用体系（ＰＡＡ－ＡＭ／ＣＴＡＢ，ＰＡＡ－ＡＭ／ＳＤＳ和ＰＡＡ－ＡＭ／ＴｒｉｔｏｎＸ－１００）中的光敏聚合反应，应用芘做荧光探针，跟踪检测在稀水溶液中分子复合和聚集的过程和微微环境特性，结果表明，由水溶性高分子／表面活性剂形成的分子聚集体，具有胶束类似的催化作用，它和胶束相经，具有更高的分子聚集能力和热力学稳定性，罗大的局部粘度和极性，因而对二苯酮／三乙     

非离子表面活性剂Brij35胶束体系中α-溴代萘的室温燐光

建立了非离子表面活性剂Ｂｒｉｊ３５胶束介质中α－溴代萘的燐光分析法，并与十二烷基 硫酸钠ＳＬＳ体系作了比较。方法特点如下：α－溴代萘在低浓度的Ｂｒｉｊ３５胶束溶液中即产生 ＲＴＰ发射，具有良好的分析特性。甲醇、乙醇等的加入，体系不会使燐光达到稳定的时间增长，测量操作简便。ＴｌＮＯ３的存在使背景降低，精密度提高。Ｂｒｉｊ３５体系比 ＳＬＳ体系具有较大 的粘度，较小的丙酮猝灭影响。     

非离子表面活性剂Brij35胶束体系中α—溴代萘的室温Ling光

建立了非离子表面活性剂Ｂｒｉｊ３５胶束介质中α－溴代萘的烯遴光分析法，并与十二烷基硫酸钠ＳＬＳ体系比了比较。方法特点如下：α－溴代萘在低浓度的Ｂｒｉｊ３５胶束溶液中即产生ＲＴＰＶ发射，具有良好的分析性。ｅｕ ｇｋ     

表面活性剂和助表面活性剂对镍的缓蚀作用

在ＨＣｌ水溶液中,三种典型的表面活性剂（ＣＴＡＢ、ＳＤＳ和Ｔｒｉｔｏｎ Ｘ－１００）对镍均有缓蚀作用,其缓蚀效率、腐蚀活化能的大小顺序是：ＣＴＡＢ〉Ｔｒｉｔｏｎ ｘ－１００〉ＳＤＳ。助表面活性剂正丁醇可作为缓蚀调节剂,其加入可控制金属镍在ＨＣｌ水溶液中的腐蚀速率。金属镍在各介质中腐蚀速率的顺序为ＨＣｌ（ａｑ）〉知性剂＋丁醇＋ＨＣｌ（ａｑ）〉表面活性剂＋ＨＣｌ（ａｑ）〉表面活性剂＋丁醇（ａｑ）〉表面     

胶束体系中光敏聚合的研究 Ⅵ．水溶性高分子／表面活性剂复合体系中光敏聚合反应

研究了水溶性高分子与三种表面活性剂组成的复合作用体系（ＰＡＡ—ＡＭ／ＣＴＡＢ，ＰＡＡ—ＡＭ／ＳＤＳ和ＰＡＡ－ＡＭ／ＴｒｉｔｏｎＸ－１００）中的光敏聚合反应．应用芘做荧光探针，跟踪检测在稀水溶液中分子复合和聚集的过程和微环境特性．结果表明，由水溶性高分子／表面活性剂形成的分子聚集体，具有胶束类似的催化作用，它和胶束相比，具有更高的分子聚集能力和热力学稳定性，较大的局部粘度和极性，因而对二苯酮／三乙胺引发ＭＭＡ光聚合具有更为显著的催化效果，使聚合速度大幅度增加．     

铀—2—（3,5—二—2—吡啶偶氮）—5—二乙氨基苯酚—Triton—X—100析相体系…

本研究了铀－２－（３，５－二溴－２－吡啶偶氮）－５－二乙氨基苯酚（３，５－ｄｉＢｒ－ＰＡＤＡＰ）－Ｔｒｉ－ｔｏｎ－Ｘ－１００析相光度体系，建立了矿石中微量铀的测定方法。在ＰＨ７．５三乙醇胺－盐酸介质中，将胶束溶液在９５±１℃。络合物即被Ｔｒｉｔｏｎ－Ｘ－１００相完全富集。     

表面活性剂增敏阴极溶出伏安法测定痕量的碘

本介绍在ＫＮＯ３－ＶＣ－ＥＤＴＡ－Ｔｒｉｔｏｎ Ｘ－１００混合底液中，用悬汞电极２．５次微分阴极溶出伏安法测定痕量碘的方法及其最佳条件。引入表面活性剂Ｔｒｉｔｏｎ Ｘ－１００可显提高灵敏度，Ｉ＾－的检测下限达０．１ｎｇ·ｍＬ＾－１（电积１８０ｓ）；引入ＶＣ可提高Ｉ＾－的稳定性（抗氧化性）；ＥＤＴＡ和ＶＣ有效率地提高了方法的抗干扰能力。用于饮水中痕量碘的分析，其相对标准偏差为３．３％（ｎ＝７），     

有机酸对非子型表面活性剂浊点的影响

有机酸对非离子表面活性剂ＴｒｉｔｏｎＸ－１００浊点的影响与酸的亲水性能、空间效应及其在胶束中的增溶位置有关。直链一元酸的加入均使浊点下降，且酸的碳链越长影响越大。直链二元酸对ＴｒｉｔｏｎＸ－１００浊点下降的影响小于直链一元酸，且碳原子数ｎｃ〈６时，使得浊点略有升高；ｎｃ≥６时，使得浊点下降。由于空间位阻作用，支链酸和取代酸使Ｔｒｉｔｏｎ Ｘ－１００浊点降低幅度较小。     

Investigation of the sorption of water vapor on cation-substituted vermiculite. 2. Thermodynamic description of sorption equilibria

The changes in the thermodynamic functions of the sorbents were calculated for the first time from measurements of the deformations of vermiculite during the sorption of water vapor and adsorption-calorimetric data.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Institute of Colloid Chemistry and the Chemistry of Water, Academy of Sciences of the Ukraine, 252180 Kiev. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1270–1275, June, 1992.     

Thermodynamics of ionization of water over wide ranges of temperature and pressure

We have summarized results of many experimental investigations of the thermodynamics of ionization of H₂O(liq.) from 0–300°C and from 1.0 atm to nearly 8000 atm. Results of these investigations (equilibrium constants, enthalpies of ionization, heat capacities, partial molal volumes, and compressibilities) have been used for a number of thermodynamic calculations. It is particularly noteworthy that it is possible to use thermal data from 0–145°C with an equilibrium constant for 25°C in calculating reasonably accurate equilibrium constants for temperatures as high as 300°C. Similarly, it is possible to use volumetric data that refer to 1.0 atm in calculating useful equilibrium constants that apply for pressures as high as 2000 atm.Much of the work reported here was done while the author was on leave at the University of Lethbridge.     

Thermochemistry of aqueous solutions of alkylated nucleic acid bases. VIII. Enthalpies of hydration of 6-alkyluracils

Enthalpies of solution in water H _sol ^o and enthalpies of sublimation H _sub ^o were determined for a number of crystalline derivatives of uracil: 1,6-dimethyluracil (m ₂ ^1,6 Ura), 1,3,6-trimethyluracil (m ₃ ^1,3,6 Ura), 6-ethyl-1,3-dimethyluracil (e⁶m ₂ ^1,3 Ura), 6-propyl-1,3-dimethyluracil (pr⁶m ₂ ^1,3 Ura) and 6-butyl-1,3-dimethyluracil (but⁶m ₂ ^1,3 Ura). Standard enthalpies of hydration H _hydr ^o and standard enthalpies of interaction H _int ^o of the solutes with their hydration shells were calculated. The data obtained show that dependence of H _int ^o on the number of-CH₂- groups of n-alkyl chain added upon substitution of diketopyrimidine ring is nonlinear. This finding is discussed in connection with results of X-ray diffraction structure determinations for the crystalline compounds.     

计量数比规则与等物质的量规则的比较

指出了计量数比规则存在的缺陷:不利于贯彻有关物质的量及其单位摩尔的SI规定,不能继承当量定律的数据资料,不能表示反应的性质,不能正确表达水硬度、碱度、树脂交换容量及电解定律,缺乏科学的导出过程及计量关系表达式,计算过程繁杂。而等物质的量规则继承和发展了当量定律,使整个滴定分析计算简单规范。     

从科学哲学的视角分析科学课堂教学——以“质量守恒定律”为例

以“质量守恒定律”为例,选取科学革命、科学问题、科学实验、归纳与重复、解释与预测等几个视角对科学课堂教学的各个环节进行了分析。通过分析,各环节中所蕴含的科学哲学内容得以显现,对科学课堂教学的认识更为全面,对科学本质的认识更加深刻。     

Thermodynamics of lonization of aqueous lodic acid,an “almost-strong” electrolyte

We have made calorimetric measurements of enthalpies of dilution of aqueous iodic acid and have used these results for evaluation of the standard enthalpy of ionization of HIO₃(aq.). We have also made calorimetric measurements of enthalpies of addition of perchloric acid solution to aqueous solutions of KIO₃, KNO₃, NaIO₃, and NaNO₃ and have used these results to obtain further values for the standard enthalpy of ionization of HIO₃(aq.). On the basis of all these results, we have selected H^o=–660±125 cal-mole^–1 as the best available standard enthalpy of ionization of HIO₃(aq.) at 298.15°K, compared to the previously accepted –2400 cal-mole^–1. Using the best available K=0.157 for ionization, we also obtain G^o=1097 cal-mole^–1 and S^o=–5.9 cal-^oK^–1-mole^–1 for ionization of HIO₃(aq) at 298.15°K.On study leave from Department of Inorganic and Analytical Chemistry, LaTrobe University, Bundoora, Victoria, 3083, Australia, to University of Lethbridge.On study leave from Department of Chemistry, University of Wollongong, Wollongong, N.S.W. 2500, Australia, to University of Lethbridge.     

Thermodynamics of vaporization of gallium trichloride

The unsaturated and saturated pressures of gallium trichloride vapor were measured by the static method with membrane-gauge manometers in wide pressure (0.2–760 Torr) and temperature (313–1071 K) intervals. Scanning calorimetry was used to determine the thermodynamic characteristics of GaCl₃ fusion. The thermodynamic characteristics were obtained for sublimation, fusion, vaporization, and association in the vapor of GaCl₃ molecules. The enthalpies of formation and the absolute entropies of GaCl₃ in the liquid and gaseous phases and Ga₂Cl₆ in the gaseous phase were calculated using literature data. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1266–1269, July, 2007.     

Thermochemistry of aqueous solutions of alkylated nucleic acid bases V. Enthalpies of hydration of N-methylated adenines

Enthalpies of solution in water, H _sol ^o , and of sublimation, H _subl ^o , were determined experimentally for a number of crystalline N-methyl adenines: m⁶Ade, m ₂ ^6,6 Ade, m⁹Ade, m ₂ ^6,9 Ade, and m ₃ ^6,6,9 Ade. Derived standard enthalpies of hydration H _hydr ^o , were corrected for the calculated cavity terms H _cav ^o to yield enthalpies of interaction H _int ^o of the solutes with their hydration shells. The increments of H _int ^o per unit area of the water-accessible molecular surface S _B , H _int ^o (CH₃)/S _B (CH₃), for the particular methyl groups: is considered to be the net effect of the gain in the energy resulting from van der Waals' interactions and of the loss in the energy due to polar interactions upon methyl substitution. It proved to vary somewhat numerically in agreement with the theoretically predicted hydration schemes of adenine. Comparison of H _int ^o /S _B value for adenine with those previously determined for uracil and thymine indicates that the aminopurine moiety is less hydrated than the diketopyrimidine ring.     

对离子反应发生条件中“放出气体”的再认识

离子反应发生条件中的“放出气体”,与其他资料中对生成物的描述不一致,也与有关反应事实不符。“放出气体”的出现,使教材中对气体生成物的描述时此时彼,没有时序性、规律性。对其与化学反应的关系及其与“生成气体”的区别进行了论述,并提出了修改的建议。     

锌在植物中的形态及生理作用机理研究进展

对锌在植物中的形态及锌在植物生理过程中的作用机理进行了综述和讨论,表明锌对碳水化合物代谢,蛋白质代谢,植物生长素代谢及细胞膜的功能和结构有很大影响。此外,锌与植物病害也有很大关系。