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61.
The swollen pore structure of a series of microporous isoporous resins (7.4–140 Å) are investigated with inverse GPC, n-alkylbenzenes and linear polystyrenes being used as probe molecules. The results indicated that, with the lowering of crosslinking degree of isoporous resins, the average pore diameter increased and the pore distribution curve broadened. All pore volume distribution obeyed a log-normal distribution. Based on the linear regression method, the experimental data were fitted to a monotonously declining exponential function and a normal distribution function by a computer, and some important structural parameters such as average pore diameter, pore volume distribution, specific surface area, etc. were obtained. The specific surface area of swollen gels were found much greater than those in the dry state measured by N2 adsorption.  相似文献   
62.
The molten salt synthesis (MSS) method is utilized to synthesize the anisotropic platelet Sr3Ti2O7 (S3T2) single-crystal particles. The aim of this study is to identify the essence of platelet Sr3Ti2O7 crystal growth and guide the synthesis of anisotropic platelet SrTiO3 crystals as well as various technologically important materials. Based on the results of X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy, the formation mechanism of platelet Sr3Ti2O7 crystals conforms to a nucleation–structure rearrangement–dissolution–diffusion in situ epitaxial growth mechanism model. First, SrCO3 reacts with TiO2 to form submicrometer SrTiO3 nuclei. Then, most of the nuclei surrounded by salt ions aggregate and rearrange to form a large SrTiO3 matrix. The structural rearrangement and the subsequent in situ epitaxial growth processes control the morphology, composition, and size of the final Sr3Ti2O7 crystals. In the synthesis process, the conversion between SrTiO3 and Sr3Ti2O7 is as follows: and the crystallographic orientation relationship between Sr3Ti2O7 and SrTiO3 in the interface is (100)S3T2//{100}ST, (010)S3T2//{010}ST, and (001)S3T2//{001}ST.  相似文献   
63.
A novel chelating resin containing sulfoxide and diethylene glycol, poly{4‐vinylbenzyl‐[2‐2‐(hydroxyethyl)ethoxyl]sulfoxide} (PVESO) was synthesized using chloromethylated polystyrene (PS‐Cl) as material. Its structure was characterized by elemental analysis, infrared spectra, and scanning electron microscopy (SEM). The adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, and Pb2+ at various pH values were determined. The maximum adsorption capacities for Hg2+ and Ag+ were 1.56 and 0.75 mmol g?1 respectively. The resin had high selectivity for Hg2+ and Ag+ over the pH range 1.0–7.0. The adsorption capacities for Hg2+ and Ag+ under competitive condition were also determined by batch experiment method. In addition, the adsorption kinetics of the resin towards Hg2+ at different temperatures was also investigated. The results showed that the adsorption rate was governed by film diffusion at 20°C and 25°C, by particle diffusion at 30°C and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6054–6059, 2006  相似文献   
64.
本文介绍了冷却器盘管破裂泄漏的情况,分析了失效破坏的原因,并提出防止冷却器盘管破裂泄漏的措施。  相似文献   
65.
刘延来  徐常滨 《大氮肥》1994,17(4):292-294
钴钼系耐硫变换催化剂硫化与水解问题一直受到人们的关注。许多研究人员对硫化水解做了大量的报道,但都以热力学平衡为基础,计算出的结果存在理论和实际相背离。因此,作者想从化学平衡和动力学双重角度对硫化与水解问题做一探讨。  相似文献   
66.
介绍了硫脲、甲硫醇、蛋氨酸、硫肥、含硫建筑材料、不溶性硫磺、Na-S电池等硫磺延伸产品情况.指出硫酸企业要以硫磺、CS2、SO2、SO3和硫酸为原料,构建多层次、多元化的精细硫化工产业链,使硫酸企业走上特色化工和精细化工之路.  相似文献   
67.
硫醇自组装膜的电化学研究进展   总被引:1,自引:0,他引:1  
综述了在金电极上硫醇自组装膜的电化学表征方法,性质和应用,介绍了自组装膜上的电子传递机理,并进行了简要的展望。  相似文献   
68.
A step‐index polymer optical fiber (SI POF) containing Rhodamine B in poly(methyl methacrylate) (PMMA) has been fabricated by a preform technique. Fluorescence of different fiber lengths were observed and discussed. A high gain (23 dB) for a SI POF with 60‐cm length, 400‐μm diameter was obtained. The Rhodamine B content of the doped SI POF is 5 ppm‐wt. The signal wavelength providing the highest gain for a 60 cm SI POF is around 630 nm, and the optimum fiber length is about 60 cm at 10 kW launched pump power. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 681–685, 2004  相似文献   
69.
The autoclave products of reduced steel-slag of an electronic furnace mainly containing C3MS2 phase were detected. The hydrothermal products of this slag included calcio-chondrodite, brucite, and hydrogarnet phases. When suitable (CaO + MgO)/SiO2 molar ratios were chosen, C3MS2 can react with SiO2 to produce calcium silicate hydrates tobermorite, xonotlite, gyrolite, and truscottite phases with different saturated water vapor pressures. The phase brucite was present along with tobermorite, whereas phases Mg-xonotlite, Mg-gyrolite, and Mg-truscottite can rarely coexist with brucite. Hydrogarnet phase disappeared when Mg-truscottite was formed.  相似文献   
70.
阐述了塑料结构壁管的基本情况和国内外现状.重点就扬子石油化工股份有限公司研究院研制的聚丙烯结构壁管专用料的情况进行了介绍。  相似文献   
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