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41.
Jatuporn Wittayakun Pongtanawat Khemthong Sanchai Prayoonpokarach 《Korean Journal of Chemical Engineering》2008,25(4):861-864
Rice husk silica (RHS) in amorphous phase with 98% purity was prepared from a waste rice husk from rice milling by leaching
with hydrochloric acid and calcination. The RHS was used effectively as a silica source for the synthesis of zeolite Y in
sodium form (NaY). The zeolite in pure phase was obtained from a two-step synthetic route in which the starting gels were
mixed, aged for 24 h at room temperature and crystallized for 24 h at 90 °C. The diameter of single crystal particles from
a scanning electron microscope was approximately 1.0 μm, whereas the average particle diameter from laser diffraction particle
size analyzer was approximately 10 μm because of the agglomeration of small crystals. Longer crystallization time in this
route resulted in a mixed phase containing NaY and zeolite P in sodium form (NaP). In addition, a one-step synthetic route
(no aging) was studied and the product was also a mixed phase zeolite. 相似文献
42.
A method to produce monodisperse magnetic composite spheres with diameters from less than 100 nm to more than 1 μm in water solution is reported. The spheres consist of a dielectric silica core and a cobalt/cobalt oxide shell which can be protected from further oxidation with an outer shell of silica or, alternatively, they can be covered with the polymer polyvinylpyrrolidone as a stabilizer. The formation of a uniform magnetic shell proceeds with the adsorption of metallic cobalt seeds, produced by the reduction of cobalt chloride with sodium borohydride, on a self‐assembled layer of polyelectrolytes on the silica core. In the second step, an outer silica shell can be formed by the hydrolysis and condensation of (3‐aminopropyl)trimethoxysilane and tetraethoxysilane. The double‐shell composite spheres show excellent sphericity, monodispersity, and a magnetic hysteresis loop at room temperature. 相似文献
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44.
Gelation Properties of Ovalbumin as Affected by Fatty Acid Salts 总被引:2,自引:0,他引:2
NAOKO YUNO-OHTA HIROKO TORYU TAKAHIKO HIGASA HIDEO MAEDA MITSUKO OKADA HIROYUKI OHTA 《Journal of food science》1996,61(5):906-910
The physicochemical properties of heat-induced ovalbumin (OVA) gels containing fatty acid salts (FAS) were investigated. Water-holding ability and transparency markedly increased in the presence of sodium caprate or sodium laurate. At 9% of the protein concentration transparent and hard gels formed; at 7%, transparent and soft gels formed. Scanning electron microscopy showed that the transparent gels had a more homogeneous structure than turbid gels without FAS. Differential scanning calorimetry indicated that denaturation temperature of OVA was decreased and the peaks became broader after addition of FAS. 相似文献
45.
This paper highlights the possibility of inverse gas chromatography for the surface characterization of common fillers (CaCO3, talc, SiO2,) for paints and coatings. Divided solids are described, on the one hand, by the dispersive component of their surface energy and, on the other, by a specific parameter indicating their acid-base interaction potential. The role of the surface morphology at a molecular level is also examined. It is demonstrated that steric effects play an important role in the adsorption of probes on lamellar solids like talc. The consequences of surface treatments as well as examples of practical applications are also reported. 相似文献
46.
主要针对核桃软糖在气温稍高、湿度较大的环境中容易粘结,造成质量下降和贮藏期缩短的现象,通过改进配方和工艺,防止和延缓核桃软糖粘结,延长了产品的贮藏时间。 相似文献
47.
溶胶-凝胶法制备疏水型SiO-2气凝胶 总被引:2,自引:0,他引:2
以正硅酸乙酯 (TEOS)为硅源 ,用三甲基氯硅烷 (TMCS)为疏水试剂 ,通过溶胶 凝胶法在室温下制备出疏水型SiO2 气凝胶。用傅立叶变温红外 (FT IR)、扫描电镜 (SEM)、透射电镜 (TEM)和吸水性能对疏水型SiO2气凝胶的结构和性能进行了研究 相似文献
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