N,N′-二(β-十八酰氧基)乙基乙二胺二乙酸钠的合成及性能研究

用 N,N′-二羟乙基乙二胺、氯乙酸钠合成了 N,N′-二羟乙基乙二胺二乙酸钠(中间体),中间体再与硬脂酰氯反应制备了一种新型 Gemini 两性表面活性剂 N,N′-二(β-十八酰氧基)乙基乙二胺二乙酸钠。对产物合成条件进行了考察,优化的反应条件为:n(硬脂酰氯):n(中间体)=2.5,溶剂 V(水):V(氯仿)=1:2,pH=9.0～10.0,反应温度15～20℃,反应时间5 h。通过红外光谱和质谱分析确定了产物结构,并测试了产物的表面性能。结果表明,在25℃时,该产物的临界胶束浓度为0.24 mmol/L,临界胶束浓度下的表面张力为35.7 mN/m;即时泡沫高度为250 mm,5 min 后泡沫高度为220 mm;乳化时间为22.48 min(甲苯-水物系)和4.65 min(正己烷-水物系),亲水-亲油平衡值为5.4,等电点为 pH 3.3～6.5。     

Synthesis and aqueous solution behaviors of sodium sulfonate‐terminated dendritic poly(ester‐amine)

Sodium sulfonate‐terminated dendritic poly(ester‐amine) (SPEA) was synthesized by sulfonation of acrylic double bond‐terminated dendritic poly(ester‐amine) (APEA) with sodium hydrogen sulfite (NaHSO₃) in mixture of diglycol and 2‐butanone under normal pressure. The structure of SPEA was characterized by IR, ¹H‐NMR, and elemental analysis. SPEA was water‐soluble. 1.0–40.0% (mass) SPEA aqueous solutions appeared as dilatant fluid. When pH value varied from 1.5 to 12.0, the viscosity of 1–5% (mass) SPEA aqueous solutions changed very small, and the electric conductivity almost kept stable within pH 3.0–10.0. The relationship between the viscosity and the concentration of SPEA water solutions was similar to that of NaCl water solutions. The surface tension of SPEA water solutions was lower than that of polyethylene glycol 2000 water solutions with the same concentration. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

从混联法生产中提取镓的研究

针对联合法厂家资源的分布特点,提出采用化学法和树脂吸附法相结合的方式实现同时回收烧结法和拜尔法循环母液中镓的新工艺,并通过小试和扩试结果分析,阐述了该工艺的可行性。     

在以纯碱为原料的非强酸性水溶液体系中采用酸碱滴定分析的误差来源及分析方法的改进

以三聚磷酸钠生产过程为例,论述了在以纯碱为原料的非强酸性水溶液体系中,由于反应不完全导致反应物中存在少量的碳酸盐,这部分碳酸盐干扰了用酸碱滴定法测量的中和度,并据此提出中和度分析改进方法.由此可以推广到其它以纯碱为原料的非强酸性水溶液体系中.     

液态金属钠高温沸腾实验回路应力分析与强度计算

本文主要完成了液态金属钠高温沸腾实验回路的应力分析与计算，确定了回路高温区连接管系的布置型式和支吊架系统，是该回路总体设计的重要组成部分。     

Evaluation of Serum Volume Losses During Long-Term Storage

Aliquots of serum collected in a large case-control study of cervical cancer were stored at −70°C for up to 4 years during implementation of the study. When 500 μL serum aliquots were thawed in preparation for carotenoid and vitamin A assays, volumes were noticeably variable and fell below 500 μL in the majority of the samples. We were concerned about evaporation/sublimation during storage of the samples because loss of water would concentrate the analytes of interest. We evaluated the use of density and sodium ion concentration measurements to confirm its occurrence. We found that serum density was an unreliable indicator of extent of volume loss since the anticipated increases in density due to evaporation were of the same magnitude as inter-individual variation in serum density. In contrast, Na⁺ concentration is tightly regulated and would rise if water had been lost from the samples. In a representative sample of serum aliquots from the case-control study, 24 of 25 vials contained less than 500 μL of serum. The mean sodium ion concentration (138.1 ± 3.6 mmol/L) was within the normal range for human serum of 136–145 mmol/L, and no correlation was observed between serum volume and Na⁺ concentration. These results strongly suggest that the observed low volumes were not due to evaporative losses. Instead, the variably low volumes of serum aliquots were probably due to pipetting errors in the initial aliquotting resulting from the use of air-displacement pipettes.     

Charge density dependence of elastic modulus of strong polyelectrolyte hydrogels

The mechanical behavior of a series of strong polyelectrolyte hydrogels based on acrylamide and 2-acrylamido-2-methylpropane sulfonic acid sodium salt (AMPS) was investigated. The hydrogels were prepared at a fixed crosslinker ratio and monomer concentration, but at various charge densities, i.e. AMPS contents between 0 and 100 mol%. The elastic modulus of the hydrogels after their preparation first increases with increasing charge density but then decreases continuously. Investigation of the swollen state properties of the hydrogels shows existence of a large number of ionic groups inside the gel that are ineffective in gel swelling. The results indicate two opposite effects of charged groups on the elastic modulus of the hydrogels: formation of multiplets acting as additional crosslinks in the gel increases the elastic modulus of ionic hydrogels, whereas the effect of the electrostatic interaction of charged groups on elastic free energy decreases the modulus.     

由对硝基苯甲醚制备对氨基苯甲醚的工艺研究

以硫磺和氢氧化钠为原料,制备多硫化钠,然后用多硫化钠还原对硝基苯甲醚合成对氨基苯甲醚。第一步反应在90℃下回流1h,硫磺的转化率可达100%;第二步反应在110℃下回流8h,对氨基苯甲醚的收率为96%,纯度为99%,副产品硫代硫酸钠的收率为92%,纯度为98%。     

从氯化铅渣中回收铅铋的研究

本文以柿竹园有色金属矿粗铋火法精炼、气化除铅产出的铅渣为原料，在常压下采用氯化钠水溶液进行浸出处理，有效地分离了铅和铋，并将铅制成了化工产品黄丹及硫酸铅     

Solubilization of unilamellar liposomes by betaine-type zwitterionic/anionic surfactant systems

The mechanisms governing the solubilizing interactions between zwitterionic/anionic mixed surfactant systems at different molar fractions of the zwitterionic surfactant (X_zwitter) and neutral or electrically charged unilamellar liposomes were investigated. The mixed systems were formed by N-dodecyl-N,N-dimethylbetaine and sodium dodecyl sulfate in the presence of piperazine-1,4-bis-(2-ethanesulfonic acid) buffer at pH 7.20. Unilamellar liposomes formed by egg phosphatidylcholine, in some cases together with stearylamine or phosphatidic acid, were used. Solubilization was detected as a decrease in static light-scattering of liposomes. Two parameters were regarded as corresponding to the effective surfactant/lipid molar ratios (Re) at which the surfactant system (i) saturated the liposomes, Re_sat, and (ii) led to a total solubilization of liposomes, Re_sol. From these parameters the bilayer/aqueous medium surfactant partition coefficients for the saturation (K_sat) and complete bilayer solubilization (K_sol) were determined. When X_zwitter was 0.40, The Re and K parameters showed a maximum, whereas the critical micellar concentration (CMC) of these systems exhibited a minimum, regardless of the electrical charge of bilayers. Given that the ability of the surfactant systems to saturate or solubilize liposomes is inversely related to the Re_sat and Re_sol parameters, these capacities appear to be directly correlated with the CMC of the mixed systems. The similarity of both K_sat and K_sol (particularly for X_zwitter=0.2–0.8) suggests that a similar partition equilibrium governs both the saturation and the complete solubilization of bilayers, the free surfactant concentration (S_a,S_b), remaining almost constant with similar values to the CMC for each mixed system studied.