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排序方式: 共有2302条查询结果,搜索用时 32 毫秒
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壳聚糖作为一种天然碱性多糖,具有高附加值、可再生资源、抑菌、无毒、易成膜、可生物降解、螯合重金属等优点。文章综述了壳聚糖在食品工农业方面的应用研究进展情况,详细介绍了壳聚糖、改性壳聚糖和复合壳聚糖在果蔬保鲜、植物诱导、防止微生物生长、果汁澄清、添加剂和食品工业废水方面的应用性能,并对壳聚糖在食品中应用的未来发展进行展望。 相似文献
93.
Chunlei Wang Jianfen Li Juntao Yan Jianmin Sun 《Korean Journal of Chemical Engineering》2014,31(9):1547-1552
A series of hierarchical mesoporous ZSM-5 zeolites with different morphology were successfully synthesized by the CO2-in-water microemulsion method, and mesoporosity was formed without organotemplate. The different synthesis conditions, including silica alumina molar ratio, stirring time and compressed CO2 pressure, were systematically investigated to discuss the influence of these conditions on the morphology of ZSM-5 zeolite. The resulting samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) and nitrogen adsorption-desorption measurement. XRD results indicated that compressed CO2 route for the synthesis of MFI zeolites had a fast crystallization rate and good crystallinity. SEM images showed that the ZSM-5 hierarchical mesoporous ZSM-5 zeolite had a uniform chain-like crystal morphology, whereas silicalite-1 displayed a monodisperse crystal morphology. In addition, the nitrogen adsorption-desorption measurement provided sufficient evidence for the presence of hierarchical mesopores in ZSM-5 zeolite. 相似文献
94.
《Electrochimica acta》1987,32(1):171-174
The breakdown damage during the anodic oxidation of tantalum has been studied through reanodization experiments. The results have been interpreted assuming the formation of non-shorting pores produced as a consequence of the breakdown process. On the basis of this model, the extent of the damaged area and the pore depth has been assessed. 相似文献
95.
《Fuel》1987,66(1):70-73
The influence on air-gasification of cokes deposited on iron ores were studied in under successive desulphurization at 750 °C under atmospheric hydrogen. Gasification promoted by steam (water: 40 μl min−1) at 350 °C for 125 min gasified 21% of the coke and allowed 25% oxidative desulphurization (based on sulphur in the coke) during the gasification and enhanced the successive hydrodesulphurization level up to 63% giving a total desulphurization of 88%. This level is comparable with that achieved after grinding. Gasification at higher temperatures, which burned more coke, was less effective in enhancing hydrosedulphurization. Gasification increases the access of hydrogen molecules to sulphur atoms in the coke. Gasification, which increases the surface area of the coke and removes the sulphur preferentially, is discussed in terms of reactivity. 相似文献
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《Computers & Structures》1987,26(4):655-665
The paper describes the development of a new hybrid computational approach for nonlinear/linear thermal-structural analysis. The proposed transfinite element approach is a hybrid scheme as it combines the modeling versatility of contemporary finite elements with transform methods and the classical Bubnov-Galerkin schemes. Application of the proposed formulations for nonlinear analysis is also developed. Several test cases are presented to include nonlinear/linear unified thermal-stress and thermal-stress wave propagations. Comparative results validate the fundamental capabilities of the proposed hybrid transfmite element methodology. 相似文献
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