胃蛋白酶与对磺酸基杯芳烃相互作用研究

采用荧光光谱法和紫外可见分光光度法研究了胃蛋白酶与对磺酸基杯芳烃和对磺酸基杯芳烃相互作用时光谱性质的变化,发现两种对磺酸基杯芳烃对胃蛋白酶的荧光均有猝灭作用,并根据Stern—Volmer方程及紫外-可见吸收光谱得出猝灭机理均为静态猝灭。根据反应的热力学参数得出对磺酸基杯芳烃对胃蛋白酶的作用力均属于静电作用力,并依据Forster无辐射能量转移理论得出荧光给体（胃蛋白酶）-受体（对磺酸基杯芳烃）间的距离r。用同步荧光光谱技术考察了两种对磺酸基杯芳烃对胃蛋白酶构象的影响。     

芳香族磺酸基化合物有机废水处理技术的研究进展

概述了芳香族磺酸基有机物的废水处理技术,分析了各种技术的优点和存在的问题,对难降解有机物的处理进行了展望,提出具有优势的处理方法。     

浅谈真空预压固结排水法在实际工程中的应用

空预压是通过覆盖于地面的密封膜下抽真空,使膜内外形成气压差,使粘土层产生固结压力。即是在总应力不变的情况下,通过减小孔隙水压力来增加有效应力的方法。真空预压是在负超静水压力下排水固结,称为负压固结。本文结合真空预压固结排水法在永定新河防潮闸工程中的应用实例,介绍了真空预压施工的准备工作,对真空预压施工方案进行了阐述,提出了真空预压施工的质量保证措施,以完善真空预压施工工艺,从而提高软基的处理水平,可供同类型工程参考借鉴。     

焦亚硫酸钠对大鼠背根节神经元L-型钙电流的影响

为了探讨二氧化硫(SO2)及其衍生物对背根节神经元的生理调节作用,应用全细胞膜片钳技术,研究了SO2衍生物焦亚硫酸钠(sodiummetabisulfite,SMB)对大鼠背根节神经元L-型钙电流(ICa,L)的影响.结果表明,SMB可增大ICa,L,且具有剂量依赖性和电压依赖性的特征.SMB可使ICa,L的激活和失活过程均向去极化方向移动,但对失活的影响要大于对激活的影响,从而可导致背根节神经元钙离子内流增大,引起细胞内钙离子浓度增加.这说明SO2及其衍生物对背根节神经元的生理功能有调节作用,当其浓度过高时也可能引起该神经元的病理生理改变.     

多壁碳纳米管对三丁基锡的吸附行为及其细胞毒性效应研究

研究了多壁碳纳米管对三丁基锡(TBT)吸附行为,主要考察了溶液pH和盐度的影响作用.同时比较了无机锡、四丁基锡(TeBT)与三丁基锡在多壁碳纳米管上吸附行为的差异,并探讨了在多壁碳纳米管存在下三丁基锡的细胞毒性作用.研究结果表明多壁碳纳米管对丁基锡具有较强的吸附能力,吸附平衡时问短,能很快达到吸附平衡.溶液pH能影响这种吸附作用.三丁基锡在多壁碳纳米管上的吸附符合Langmuir和Freundlich吸附等温式,主要为疏水作用.在与多壁碳纳米管的共存体系中三丁基锡的细胞毒性效应有所削弱,这可能与多壁碳纳米管对三丁基锡的吸附作用有关.     

Adsorption characteristics of humic acid-immobilized amine modified polyacrylamide/bentonite composite for cationic dyes in aqueous solutions

Humic acid-immobilized amine modified polyacrylamide/bentonite composite (HA-Am-PAA-B) was prepared and used as an adsorbent for the adsorption of cationic dyes (Malachite Green (MG), Methylene Blue (MB) and Crystal Violet (CV)) from aqueous solutions. The polyacrylamide/bentonite composite (PAA-B) was prepared by intercalative polymerization of acrylamide with Nabentonite in the presence of N,N0-methylenebisacrylamide as a crosslinking agent and hexamethylenediammine as propagater. PAA-B was subsequently treated with ethylenediammine to increase its loading capacity for HA. The surface characterizations of the adsorbent were investigated. The adsorbent behaved like a cation exchanger and more than 99.0% removal of dyes was detected at pH range 6.0–8.0. The capacity of HA-Am-PAA-B was found to decrease in the following order: MG > MB > CV. The kinetic and isotherm data were interpreted by pseudo-second order rate equation and Freundlich isotherm model, respectively. Experiments were carried out using binary solute systems to assess the competitive adsorption phenomenon. The experimental isotherm data for each binary solute combination of MG, MB and CV were analyzed using Sheindrof-Rebhun-Sheintuch (SRS) (multicomponent Freundlich type) equation.     

Effect of background electrolytes on the adsorption of nitroaromatic compounds onto bentonite

To further elucidate interaction of nitroaromatic compounds with mineral surface, the sorption of m-dinitrobenzene (m-DNB) and nitrobenzene to original bentonite in aqueous solution containing di erent electrolytes (i.e., KCl, NH4Cl, CaCl2 and Tetramethylammonium bromide (TMAB)) was studied. The sorption of m-DNB was greatly enhanced with the presence of KCl and NH4Cl, while little influence was observed with CaCl2 and TMAB, following the order of KCl > NH4Cl TMAB, CaCl2, or DI water. For nitrobenzene, sorption enhancement only occurred at high nitrobenzene concentrations in the presence of KCl, and the solute equilibrium concentration at inflexion point was lowered with increasing KCl concentration. These sorption enhancements were significantly promoted with the increase of electrolyte concentration. The salting-out e ect is insu cient to account for the sorption enhancement by original bentonite with increasing KCl or NH4Cl concentration. X-ray di raction patterns of bentonite suspensions indicated that the sorption enhancement of m-DNB was attributed to the intercalation of K+ or NH4 + into bentonite interlayer and then dehydration with m-DNB to form inner-sphere complexes, which caused previously expanded bentonite interlayers to collapse in aqueous suspension, thus further enhanced the interaction of phenyl with siloxane surface. In comparison, the sorption enhancement of NB is attributed to the formation of outer-sphere complexes with K+ at high solute-loadings (> 200–400 mg/kg). The sorption of m-DNB to initially modified TMA+-bentonite and K+-bentonite was almost the same as respective sorption to original bentonite in solution containing TMA+ and K+.     

钠钙双碱法在中小型燃煤锅炉脱硫改造中的应用

介绍了钠钙双碱法脱硫除尘原理,并应用于某热源厂的锅炉烟气脱硫除尘改造工程。燃煤锅炉烟气先经陶瓷管旋风除尘器预除尘,然后在喷淋塔中经增湿降温钠碱溶液吸收SO2,吸收液用石灰乳将其再生后循环使用,最终产物以亚硫酸钙和石膏的形式析出。实践证明,钠钙双碱法具有操作简便、效率高且稳定等特点,是适应当前环境保护要求的实用型脱硫技术。     

紫外分光光法测定苯胺类化合物的注意事项及解决方法

对国标法(GB 11889-89)中的N-(1-萘基)乙二胺偶氮分光光度法测定水中苯胺类化合物进行了深入研究,同时指出了苯胺类化合物测定全过程中应注意的问题及解决方法。应用改进过的方法测定水中苯胺类化合物,方法快速、准确、简便,检出限为0.03 mg/L。应用该方法分别对金华市地表水及工业废水中的苯胺类化合物进行检测,加标回收率为93.1%~104%。     

HAZOP技术在溴化丁基橡胶装置的应用

介绍了危险与可操作性分析(HA-ZOP)的程序以及在溴化丁基橡胶装置的应用,根据分析结果提出相应的安全措施。