响应面法优化固定化碱性蛋白酶工艺

采用多孔壳聚糖微球吸附和戊二醛交联的方法,将碱性蛋白酶固定于壳聚糖上.在pH、加酶量、温度、戊二醛体积分数和固定化时间5个单因素试验的基础上,利用响应面分析法对固定化碱性蛋白酶的工艺条件进行了优化.结果表明:在pH 9.20、加酶量7 512 U/g、固定化温度44.58℃、戊二醛体积分数0.20%、固定化时间8.11 h的最佳工艺条件下,酶的回收率高达56.73%.     

紫外线吸收剂/分散染料同浴上染涤纶的性能

采用高温高压吸尽法将紫外线吸收剂和分散染料单独及同浴上染到涤纶织物上,比较了两种上染条件下紫外线吸收剂和分散染料对涤纶织物上染率,分别计算出两者对涤纶纤维的亲和力,并测定了所得织物的表观颜色深度值和耐光色牢度。探讨紫外线吸收剂与分散染料在同浴上染过程中的相互影响。结果表明:当紫外线吸收剂与分散染料同浴对涤纶织物进行上染时,两者的上染率都比单独上染时的上染率低,表现出了一定的竞染关系;所选用的紫外线吸收剂都能在一定程度上提高染色织物的耐光色牢度,其中以紫外线吸收剂UV-3改善分散染料所染涤纶织物耐光色牢度的效果最为明显。选用的紫外线吸收剂对分散染料在织物上的色光基本无影响。     

Wettability and surfactivity of sodium phosphate surfactants in strong alkali solutions

The wettability, surfactivity and the correlation between wettability and surfactivity of sodium diethylhexylphosphate, sodium diethylhexyl polyoxyethylene phosphate and their complex in NaOH solutions were studied. A complex alkali resistant phosphate surfactant with good permeability was prepared. The wettability of surfactants was investigated by measuring the immersion time, sinking time and capillary effects of nature cotton grey fabric in NaOH solutions. The surfactivity of the surfactants was characterized by measuring the surface tension. The effect of the complex on the surface appearance of cotton grey fabric was also investigated with a scanning electron microscope (SEM). The results show that all the surfactants exhibit good wettability for cotton grey fabric in 0.5–5.0 mol/L of NaOH solutions, the complex system exhibits better wettability in 5.0–7.0 mol/L of NaOH solutions, in comparison with either corresponding single surfactant component employed, and wettability is well correlative with the surfactivities of the surfactant. SEM images indicate that the cotton grey fabric is well wetted by the alkaline surfactant solution and the quality of fabric is improved.     

煤气化过程中单颗粒吸收剂脱硫反应模型概述

对煤气化过程中吸收剂脱硫反应的气固反应模型进行了概述.气固反应模型大致可分为未反应缩核模型,晶粒模型、孔模型及逾渗模型等几种基本型式.未反应缩核模型结构比较简单,可以作为其它模型的基础和组成部分,晶粒模型应用较为广泛且已经得到了充分的发展和改进,孔模型侧重于颗粒内部孔隙特性对反应影响的分析,逾渗模型则基于孔模型将逾渗理论引入来描述脱硫反应过程.     

Inhibitory effect of Cr（Ⅵ） on activities of soil enzymes

To evaluate the influence of various Cr(VI) concentrations (0.05, 0.25, 0.50, 1.00 and 2.00 g/kg) on the activity of soil enzymes, the activities of catalase, polyphenol oxidase, dehydrogenase, alkaline phosphatase in soils were investigated in the incubation experiment with a period of 35 d. The results indicate that all the tested Cr(VI) concentrations significantly inhibit dehydrogenase activity by over 70% after 35 d. The activity of alkaline phosphatase is slightly inhibited during the whole experiment except for on the day 7. Cr(VI) has no obvious effect on the activity of catalase in soil. On the contrary, Cr(VI) stimulates the activity of polyphenol oxidase. The results suggest that dehydrogenase activity can be used as an indicator for assessing the severity of chromium pollution. Foundation item: Projects(2006AA06Z374, 2007AA021304) supported by the National High-Tech Research and Development Program of China; Project(2008SK2007) supported by the Key Program of Science and Technology of Hunan Province, China     

Alkaline treatment kinetics of calcium phosphate by piezoelectric quartz crystal impedance

Calcium phosphate film was prepared by electrochemical deposition technology. Subsequently, the alkaline treatment process of calcium phosphate film in 0.1 mol/L NaOH solution was monitored on real time by the piezoelectric quartz crystal impedance (PQCI) technique. The variations of morphology and composition for the alkaline treatment products were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD), respectively. The dynamic variations of calcium phosphate can be characterized by the change of equivalent circuit parameters. The results show that the forming process of hydroxyapatite (HA) is composed of three stages: (1) acidic calcium phosphate dissolution; (2) phase transformation; and (3) HA formation. Furthermore, the correlative kinetic equations and parameters are obtained by fitting the static capacitance (C _s)—time curves. Foundation item: Project(2005CB623901) supported by the Major State Basic Research and Development Program of China     

煤炭复合型助燃固硫剂的开发与研究

通过对不同粒径煤样的全硫量及黄铁矿硫量的测试分析,以及在燃烧过程中生成酸性气体,从而选用复合型碱性固硫剂来进行固硫试验。通过对这几种试验方案的优选比较分析,确定按煤90%∶CaO 9%∶NaCl 1%的配方脱硫率高且成本低廉,可适合工业化生产使用。同时,用高精度微机全自动量热仪做上述配方的煤燃烧热效率实验,结果表明,煤热效率有明显的提高。这说明复合型碱性添加剂不但可促进煤炭的燃烧,同时在燃烧的过程中取到固硫的作用。     

产高温碱性蛋白酶菌株筛选及酶学性质研究

从高温堆肥土样中筛选到一株高产蛋白酶的菌株,经鉴定为Bacillus subtilis,命名为I15.对最适产酶发酵条件进行了优化,并研究了发酵产蛋白酶的酶学性质.结果表明,玉米淀粉和豆饼粉是该菌发酵产蛋白酶的最适经济碳氮源;该蛋白酶属高温碱性蛋白酶,具有很强的热稳定性和酸碱稳定性.另外,突出的性质是该蛋白酶对表面活性剂和温和型去垢剂具有超强的耐受性,将具有广阔的市场前景.     

碱性蛋白酶水解豌豆蛋白的条件优化

采用碱性蛋白酶对豌豆蛋白进行水解,通过单因素试验,分析了温度、pH、酶与底物浓度比、底物浓度、水解时间对水解度影响,并在单因素试验的基础上,利用响应面分析法,优化确定的豌豆蛋白酶水解最佳条件为:温度54.5℃,pH7.9,酶与底物浓度比1.5%,底物浓度2.9%,水解时间3.0 h,最佳酶水解条件下的水解度为13.42%.     

碱性[Bmim]Im离子液体催化合成DEHC

研究了在1-丁基-3-甲基咪唑阳离子与咪唑阴离子搭配的碱性[Bmim]Im离子液体催化作用下,碳酸二甲酯(DMC)与异辛醇(EHOH)通过两步酯交换法制备碳酸二异辛酯(DEHC)的合成工艺.确定了合成DEHC的最佳反应条件为:催化剂用量为原料总质量的2.0%,醇酯摩尔比为4:1,一步反应温度90℃,反应时间2 h,二步...