The chelate molecule, ethylenediamine, was incorporated onto the surface of ramie fiber via sequential reactions of the hydroxyl groups on ramie fiber with epichlorohydrin followed by the chelating agent. The performance of the modified material (CelNH) was characterized by Fourier transform infrared spectroscopy (FI-IR), X-ray diffraction (XRD), scanning electron micrographs (SEM), thermogravimetry analysis (TGA), UV–Vis, and elemental analysis. Results show that the excellent characteristics of the raw fiber were still remained after modification although the crystallinity of the modified fiber decreased. The modification parameters were optimized as the concentration of ethylenediamine of 0.75 mol/l, the temperature of 50 C, and the reaction time of 5 h. Meanwhile, the dye of C.I. reactive red 2 was used to study the dyeability of the raw and the modified fibers. The color strength and the dye uptake of the modified fiber increased obviously with an increase in the nitrogen contents in CelNH. The color strength and the dye uptake of the modified fiber can be controlled by changing the extent of surface modification of raw ramie fiber.

在35～55 ℃、7～15 MPa条件下,利用果胶粗酶液和木聚糖酶液,对苎麻韧皮进行超临界CO2 处理及其脱胶试验,考察了超临界CO2 处理苎麻韧皮前后酶液中的活菌数、酶活和脱胶效果。实验结果表明,经超临界CO2 处理1 h左右,苎麻脱胶菌的致死率在99 %以上;不同类型非纤维素降解酶,在超临界条件下的稳定性不同,木聚糖酶比较稳定,酶活仅降低1.6 % ,而果胶粗酶液的稳定性较差,酶活降低23.79 %；超临界CO2 介质有利于加速苎麻酶的脱胶催化反应进程,使苎麻脱胶效果提高60 %～100 %。

对亚麻快速生物脱胶和温水沤麻过程中的果胶酶、木聚糖酶、纤维素酶、微生物、pH 值和还原糖等进行了动态变化研究。结果表明,2 种脱胶过程中果胶酶和木聚糖酶的变化趋势基本相似,酶活性脱胶前期均增加缓慢,中后期迅速增加;纤维素酶活性的变化趋势有明显的区别,快速生物脱胶的纤维素酶酶活性增加幅度小,酶活性低(0105 IUPmL左右) ,温水沤麻的纤维素酶在发酵72 h后迅速增加,脱胶完成后酶活性达0. 337 9 IUPmL ;微生物的变化趋势基本相似,在脱胶前期迅速增加、脱胶完成时开始下降;pH值和还原糖量的变化趋势分别呈“U”型和“M”型。

近年来,超临界二氧化碳(sc-CO2 ) 在聚合反应中的应用受到了越来越多的关注。本文主要综述了以sc-CO2 为反应介质的自由基聚合、阳离子聚合、过渡金属催化聚合、热致开环聚合、溶胶2凝胶聚合以及氧化耦合聚合的研究概况。一系列研究结果表明sc-CO2 是非常有前途的反应溶剂,在高分子合成领域将会有更加广阔的应用前景

A series of AOT (aerosol-OT) analogue surfactants (sodium salt of dibutyl-2-sulfosuccinate, sodium salt of dipentyl-2-sulfosuccinate, sodium salt of dihexyl-2-sulfosuccinate, and sodium salt of dioctyl-2-sulfosuccinate) were synthesized and characterized by 1H NMR and elemental analysis. A static method coupled with gravimetric analysis is developed to measure the solubility of the surfactants in 1,1,1,2-tetrafluoroethane (HFC-134a) and supercritical CO2 (scCO2). The solubilities of the surfactants in HFC-134a and scCO2 are affected by the temperature, pressure, and carbon atom number of the surfactant. The solubility of the same surfactant in HFC-134a solvent is approximately two times that in the most commonly used supercritical solvent CO2. The pressuretemperature phase diagrams for water/HFC-134a microemulsions stabilized by the surfactants were determined using cloud-point measurements for a concentration range of the surfactant from (1.85 _ 10-3 to 5.60 _ 10-3) M, temperature up to 338 K, and pressure up to 40 MPa in a high-pressure vessel. At a fixed temperature, the cloud-point pressure increased with increasing water-to-surfactant molar ratio (Wo). At a fixed Wo, the cloudpoint pressure decreased with increasing temperature. The surfactant with the longest hydrocarbon chain has the highest cloud-point pressure even at lower surfactant concentrations.