用化学计量法研究CO2—n—C7H16系的高压相平衡

测定了在温度３１０．６５Ｋ、３２３．１５Ｋ和压力３．１３～７．５４ＭＰａ条件下的气液平衡数据，实验结果与文献值具有较好的一致性。用ＴＲＫ状态方程对实验所得数据进行关联，取得了较满意的结果。     

生物代谢过程的热力学研究——乙醇生成的理论转化率及代谢能级特征

根据生物代谢状态方程和代谢反应一般表达式,解析由葡萄糖生成乙醇的生物代谢过程。结果表明,该过程是一个可达到热力学最大可能性的过程,该代谢过程的热力学最大可能性转化率为51.1%,方程的解与依据代谢途径直接核算的结果一致,说明这些代谢途径已实现了热力学上的最大可能性。研究表明由葡萄糖生成乙醇的代谢过程具有非连续的能级特征。研究结果为深入解析代谢过程的物理意义奠定了基础。     

机体阴阳交感现象的熵变分析

借用非平衡热力学理论,分析自然界水火运动的规律,得出结论——阴阳交感过程是熵减少过程,阴阳反作过程是熵增加过程;机体的许多阴阳变化也遵循同一规律。并在此基础上论证了新陈代谢过程是机体从外界输入负熵以抵消体内正熵产生的过程,从而推知阴阳交感现象发生的原因是新陈代谢。     

超声辅助大孔树脂技术富集荆芥穗中总黄酮和总酚的工艺研究

目的 通过超声辅助大孔树脂对荆芥穗Schizonepetae Spica水提物中总黄酮和总酚类化合物进行富集并对比处理前后化合物含量及活性变化。方法 从7种不同类型树脂中筛选超声辅助最佳树脂型号,在吸附动力学和吸附热力学研究下,对超声温度、功率、上样质量浓度及解吸溶剂百分比等影响因素进行工艺优化。测定了优化处理前后各成分含量及活性变化。结果 动力学和热力学的研究表明,荆芥穗总黄酮适用于Langmuir模型,且吸附过程为自发吸热熵增,总酚则为自发放热熵减并适用于Freundlich模型,据此不同的吸附机制优化了2类成分同时富集的最佳工艺,在超声辅助AB-8大孔树脂,温度25 ℃、时间2.5 h,功率150 W,上样质量浓度0.1 g/mL,70%乙醇解吸附的过程下,荆芥穗水提物中总黄酮和总酚类化合物含量增加2～3倍,其单体成分的含量及抗氧化和神经氨酸酶抑制活性均显著增加。结论 超声辅助大孔树脂技术为荆芥穗总黄酮和总酚类成分的有效可行富集技术。     

反相气相色谱法测定溶剂在PBMA中的无限稀释活度系数

用反相气相色谱方法测定了１６种溶剂在聚甲基丙烯酸丁酯（ＰＢＭＡ）中３４３￣４３３Ｋ范围内的无限稀释活度系数,并用周浩等的高分子溶液分子热力学模型对实验结果进行了关联,结果令人满意。     

The Binding of Cyclosporin A to Human Plasma: An in Vitro Microdialysis Study

Purpose. The human plasma binding of cyclosporin A was studied in vitro using the technique of microdialysis. The effect of temperature on the overall binding interaction between cyclosporin A and human plasma was also investigated. Methods. Flow-through loop-type microdialysis probes were constructed from fused silica tubing and regenerated cellulose tubing with a MWCO of 13000 daltons. Probes were perfused with phosphate buffer (0.5 µl/min) and the concentration of ³H-cyclosporin A in the well-mixed medium (plasma or buffer) was 1200 ng/ml. Relative recoveries of cyclosporin A from plasma or buffer were determined for each probe by separate experiments to measure the solute gain or loss with reference to the perfusate. Results. Recoveries determined by loss were significantly greater than those determined by gain and in each case temperature dependent, with higher recoveries at higher temperatures. The plasma free fraction of cyclosporin A calculated from the recovery data and the perfusate to plasma concentration ratios was dependent on temperature in a log-linear fashion. Mean ± s.d. plasma free fractions expressed in percent were 33.5 ± 4.6, 17.9 ± 3.6, 6.2 ± 0.8, 3.0 ± 0.6, and 1.5 ± 0.2 at temperatures of 4, 10, 20, 30, and 37°C, respectively. Assuming that the enthalpy of binding is constant over the temperature range studied and pseudo-first order conditions exist, the binding reaction at these temperatures was spontaneous, endothermic (H = 74.0 kJ/mole), and entropically driven (S = 0.274 kJ/mole/deg). Conclusions. These results show that the free fraction of cyclosporin A in human plasma is dependent on temperature with the fraction unbound decreasing with temperature in the range of 4 to 37°C. The thermodynamic parameters for the binding of cyclosporin A to plasma components indicate that the reaction is a spontaneous endothermic reaction that is mainly entropy driven, similar to the partitioning of lipophilic molecules from an aqueous to a hydrophobic phase. Moreover, these results show that microdialysis is a feasible method to determine the binding interactions between plasma and cyclosporin A, which indicates the method may be suitable for other difficult binding studies where the solutes have nonspecific binding to separation devices.     

微量热分析在中医药研究中的应用

针对我国中医药现代化研究的现状和问题,结合微量热分析技术的特点和优势,认为基于生物热动力学的微量热分析有可能在中医药研究中发挥独到而突出的作用,建立基于生物热动力学表达的中药四性评价、品质鉴定、药效物质筛选、复方配伍关系分析等研究方法体系,可望为中医药现代化研究提供新的技术支撑。     

苦叶七中类黄酮提取的动力学及相关热力学研究

目的:对苦叶七中类黄酮浸提的动力学及相关热力学进行研究.结果:以Fick扩散第二定律为基础,并由此推算出浸提的速率常数、活化能、相对萃余率、半衰期、以及平衡常数、摩尔焓变、摩尔熵变、摩尔吉布斯焓变、摩尔亥姆霍兹焓变等动力学和热力学函数值.结论:为苦叶七类黄酮提取的工艺设计及操作条件的选择提供有价值的理论依据.     

Energetics and Mechanism of Conformational Transitions of Protein‐Like NIPAM‐Sodium Styrene Sulfonate Copolymers in Aqueous Solutions

Protein‐like and random NIPAM‐sodium styrene sulfonate copolymers of similar composition have been prepared by radical polymerization in water at temperatures above and below the LCST of PNIPAM, respectively. Thermal transitions of the copolymers in aqueous solutions have been studied by means of dynamic light scattering, viscometry, and high‐sensitivity differential scanning calorimetry. The phase separation or cooperative conformational transitions without phase separation were observed for the random or the protein‐like copolymers, respectively. Transition temperature, enthalpy, and heat capacity increment of the protein‐like copolymer differed insignificantly from those of the random copolymer of similar composition. The transition heat capacity increments of the protein‐like copolymers revealed that only 10–20% of their NIPAM links participate in the formation of a dense water‐free globule core. The coil–globule transitions of the protein‐like copolymers were described by the thermodynamic three‐state model according to the scheme “random coil?condensed coil?globule”, which is known to simulate the folding mechanism of globular proteins.

     

非平衡态热力学理论在证候热力学研究中的应用

引入非平衡态热力学理论,诠释中医阴阳理论.借助红外成像获得的人体体表脏腑三焦等对应区域热值数据和排序,以坐标图形式表达人体区域热值数据高低(人体热结构),确立中医证候热力学研究的思路和方法,提出健康人脏腑三焦等人体热结构符合耗散结构,不同证候出现不同人体热结构,辨证论治就是根据脏腑寒热偏离,用中医方法恢复人体正常热结构的调整.