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991.
青海盐湖部分氯化物型卤水中,由于钙的循环积累,其浓度不断增高,这可能对从卤水中提取氯化钾带来一定影响。实验研究了该类型高钙含钾卤水对4#工艺制取氯化钾的影响,研究结果表明卤水中钙含量对4#工艺制取氯化钾影响较小。 相似文献
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Yixing Wang Liheng Dai Kai Qu Lu Qin Linzhou Zhuang Hu Yang Zhi Xu 《Frontiers of Chemical Science and Engineering》2021,15(4):892-901
Photocatalytic membranes have received increasing attention due to their excellent separation and photodegradation of organic contaminants in wastewater. Herein, we bound Ag-AgBr nanoparticles onto a synthesized polyacrylonitrile-ethanolamine (PAN-ETA) membrane with the aid of a chitosan (CS)-TiO2 layer via vacuum filtration and in-situ partial reduction. The introduction of the CS-TiO2 layer improved surface hydrophilicity and provided attachment sites for the Ag-AgBr nanoparticles. The PAN-ETA/CS-TiO2/Ag-AgBr photocatalytic membranes showed a relatively high water permeation flux (~ 47 L·m–2·h–1·bar–1) and dyes rejection (methyl orange: 88.22%; congo red: 95%; methyl blue: 97.41%; rose bengal: 99.98%). Additionally, the composite membranes exhibited potential long-term stability for dye/salt separation (dye rejection: ~97%; salt rejection: ~6.5%). Moreover, the methylene blue and rhodamine B solutions (20 mL, 10 mg·L−1) were degraded approximately 90.75% and 96.81% in batch mode via the synthesized photocatalytic membranes under visible light irradiation for 30 min. This study provides a feasible method for the combination of polymeric membranes and inorganic catalytic materials. 相似文献
994.
Characteristics of reaction and product microstructure during light calcination of magnesite in transport bed 下载免费PDF全文
A gas-heating laboratory transport bed was adopted to simulate the industrial transportbed reactor for flash calcination of magnesite, and a method based on TG analysis of a reacted sample was further developed to calculate the decomposition rate or conversion of its containing MgCO3. The study investigated how the conversion and product reactivity as well as microstructure vary with reaction conditions including temperature, particle size and times of re-calcination for powder magnesite. Magnesite powder (<150 μm) calcination is a quick reaction that reaches 98% decomposition of its containing MgCO3 in 1—2 s,corroborating the feasibility of magnesite flash-calcination in transport bed reactors. The coloration time given by the citric acid chromogenic method was 17—55 s and 294 s for the obtained products from transport and fixed beds, respectively. This proves the obviously higher activity and thus improved microstructure of the product from transport bed. During the calcination process, the MgO grain size of the product gradually increases, and the surface structure changes from loose and porous to dense and smooth. This structural change can be completed within a few seconds. 相似文献
995.
Comparison of the crystalline properties and structural changes of starches from high-amylose transgenic rice and its wild type during heating 总被引:1,自引:0,他引:1
Cunxu Wei Fengling Qin Weidong Zhou Bin Xu Chong Chen Yifang Chen Youping Wang Minghong Gu Qiaoquan Liu 《Food chemistry》2011
A transgenic rice line (TRS) enriched amylose and resistant starch has been developed by antisense RNA inhibition of starch branching enzymes. In this study, gelatinisation and crystalline properties, swelling power, water solubility, morphological and structural changes of starches from TRS and its wild-type Teqing (TQ) were carefully investigated during heating. Compared to TQ, TRS starch showed higher gelatinisation temperatures, lower gelatinisation enthalpy and swelling power. Morphological and structural changes showed that TQ starch drastically swelled after 70 °C, then gradually disrupted with increasing heating temperature. The surrounding band of TRS starch restrained granule swelling, though the subgranules disrupted to form the cavity. The results of spectroscopic analyses indicated that A-type crystalline of TQ changed to amorphous starch after 75 °C, while C-type crystalline of TRS gradually changed to B-type crystalline after 75 °C, then became amorphous starch at 95 °C. These results add to our understanding of the effect of heating on the high-amylose rice starch. 相似文献
996.
甲基蓝体系共振瑞利散射法测定蛋白质 总被引:2,自引:0,他引:2
在pH2.36的BR介质中,甲基蓝与蛋白质相互作用生成复合物,使最大波长350nm的共振光散射光谱得到增强,增强程度与蛋白质浓度成正比。据此建立了测定蛋白质的新方法。人血清白蛋白、牛血清白蛋白的线性范围分别为0~2.4mg/L、0~2.8mg/L,相应检出限分别为39.3、43.4μg/L。方法的稳定性好,灵敏度高,用于牛奶、豆浆、人血清、尿液中总蛋白质的测定,结果与考马斯亮蓝法一致。 相似文献
997.
海藻酸钙固定化细胞及其在食品工业中的应用 总被引:16,自引:0,他引:16
综述了海藻酸钙的性质、固定化细胞的制备方法,稳定性及在食品工业中的应用。 相似文献
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