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321.
从香蕉淀粉中制备麦芽糊精和果葡糖浆的研究   总被引:1,自引:0,他引:1  
从香蕉中分离的淀粉,在抗高温α-淀粉酶的水解作用下,可制得葡萄糖值(DE)低于20的麦芽糊精.香蕉麦芽糊精同玉米麦芽糊精相比,颜色更白,色差(△E)更大,具有适宜用在食品工业的理化特性.香蕉淀粉水解完成后,在淀粉葡萄糖苷酶和普鲁兰酶的作用下,经60℃,24 h糖化后可制得果葡糖浆.香蕉果葡糖浆的化学特性与玉米果葡糖浆相似,但色泽更清晰,色泽的稳定性也略高于玉米果葡糖浆.  相似文献   
322.
Nano-structures of a new discrete coordination compound of divalent cobalt with the pyrazol (pzH) containing the terminal isothiocyanate anions, [Co(pzH)2(NCS)2] (1), with discrete molecular architecture in solid state was synthesized by a sonochemical method. The new nanostructure was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, IR, and elemental analysis. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The discrete molecules interact with each other through labile interactions creating a 3D supramolecular framework. The CoO nanoparticles were obtained by thermolysis of 1 at 180 °C with oleic acid as a surfactant.  相似文献   
323.
A novel aza-aromatic base adduct of a cadmium(II) fluorine-substituted β-diketonate, [Cd(dmp)(ttfa)2]n(1), (“dmp” is an abbreviation for 2,9-dimethyl-1,10-phenanthroline and “ttfa” is an abbreviation for thenoyltrifluoroacetonate) was synthesised and characterised by elemental analysis and IR, 1H NMR and 13C NMR spectroscopy and studied by thermal as well as X-ray crystallography. The single-crystal structure of this complex shows that the coordination number of the Cd2+ ion is six with two N-donor atoms from the dmp ligand and four O-donors from ttfa. Self-assembly of this complex was mediated by CH···F–C and π–π stacking interactions. The supramolecular features of these complexes are controlled by weak directional intermolecular interactions. The structural energy of the title complex was determined by density functional theory calculations. The calculated HOMO–LUMO gap is 0.131 a.u. (3.474?eV). The CdO nano-particles were obtained by thermolysis of 1 at 180?°C with oleic acid as the surfactant. Scanning electron microscopy showed that the size of the CdO particles is ~35?nm.  相似文献   
324.
Interest is increasing in plastic compounding plants that offer tailor‐made resins. Such plants produce a wide range of products in small quantities and with frequent changeovers. The underlying scheduling problem has been extensively researched; however, the concept of incorporating qualities of the finished product in the problem of plastics compounding has not been considered. We express product qualities as an additional problem constraint so that the production schedule ensures product quality. The additional constraint makes this mixed integer nonlinear program (MINLP) problem more difficult to solve. Several case studies are solved to illustrate the utility of the proposed approach. Experiments demonstrated that qualities of the finished product can be ensured a priori if the appropriate relations are developed and integrated in the optimisation model. As well, this paper provides insight into the economic aspects of the scheduling problem under consideration. Experiments showed that none of the cost components (operation, raw material, inventory, penalty or utilities) can alone play the role of the optimisation criterion. © 2012 Canadian Society for Chemical Engineering  相似文献   
325.
BACKGROUND: Dyeing effluents are the main source of water pollution from textile industries. Consequently, the treatment of such effluents is of environmental concern. RESULTS: Decolorization of a textile industry effluent was investigated using, for the first time, the trimeric Scytalidium thermophilum laccase without mediator addition. The maximum effluent decolorization (50%) was achieved after 8 h using a diluted effluent (5 fold) and 4 units of crude enzyme, operating at 50 °C and pH 4. Characterization of raw effluent presents two peaks as demonstrated by the UV‐visible spectrum, showing an intensive peak around 670 nm and a smaller one at 290 nm. At the end of the enzymatic treatment, these two peaks disappeared and a new peak emerged at 280 nm. Because laccase catalyzed effluent decolorization percentage did not exceed 50%, an alkaline adapted consortium treatment assay of this effluent was carried out. An alkaline adapted consortium was used at bench scale in order to decolorize the raw effluent. After 24 h of exposure, color and COD (chemical oxygen demand) removal rates reached 73% and 71%, respectively, at pH 11. CONCLUSION: The adapted consortium treatment of the industrial effluent is economically very interesting since the treatment is costless and can be applied at pilot or industrial scales. © 2012 Society of Chemical Industry  相似文献   
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