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排序方式: 共有134条查询结果,搜索用时 15 毫秒
61.
Faik Ahmet Ayaz Sema Hayırlıoglu-Ayaz Sengul Alpay-Karaoglu Jiři Grúz Kateřina Valentová Jitka Ulrichová Miroslav Strnad 《Food chemistry》2008
Nine phenolic acids were identified and quantified by HPLC–MS in leaves and 10 in seeds of kale (black cabbage). The free, ester (methanol-soluble), glycoside and ester-bound (methanol-insoluble) phenolic acid contents of the leaves were 487, 532, 4989 and 6402 ng/g fresh weight, respectively. Ferulic and caffeic acids (total contents; 4269 and 4887 ng/g, respectively) were the most abundant. The seed contents of these fractions were 1993, 1477, 1231 and 4909 ng/g dry weight (DW), respectively, and sinapic acid was the most abundant (5037 ng/g DW). The fractions’ total phenolic contents, determined colorimetrically, were highly correlated with their DPPH scavenging capacity, and in antimicrobial activity assays, with nine test organisms representing a wide array of taxa, all of the fractions were effective against Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis and (most strongly) Moraxella catarrhalis. Antimicrobial and antioxidant activities of kale phenolics in free and conjugated forms are discussed. 相似文献
62.
决策支持系统(DSS)是当前信息技术研究和应用的热点,DSS特别是基于ERP系统的DSS是企业信息化的发展方向。介绍了国内外炼化企业决策支持系统的应用现状及发展趋势,对DSS的基本原理、系统构成、实施要点等进行了重点分析,结合炼化企业信息系统建设实际,对于企业如何更好地建设好利用DSS,提出了建议。 相似文献
63.
Noncondensable gases that come from the containment and the interaction of cladding and steam during a severe accident deteriorate a passive containment cooling system's performance by degrading the heat transfer capabilities of the condensers in passive containment cooling systems. This work contributes to the area of modeling condensation heat transfer with noncondensable gases in integral facilities. Previously existing correlations and models are for the through-flow of the mixture of steam and the noncondensable gases and this may not be applicable to passive containment cooling systems where there is no clear passage for the steam to escape. This work presents a condensation heat transfer model for the downward cocurrent flow of a steam/air mixture through a condenser tube, taking into account the atypical characteristics of the passive containment cooling system. An empirical model is developed that depends on the inlet conditions, including the mixture Reynolds number and noncondensable gas concentration. 相似文献
64.
Miscanthus × giganteus is a triploid hybrid propagated vegetatively from rhizomes or in a tissue culture, so its clones are characterised by a very low genetic diversity. Giant Miscanthus is cultivated mainly for biomass used as biofuel; depending on its chemical composition, it can be used in many industries. The goal of this work was to determine whether regenerants obtained in tissue culture can be a source of new forms characterised by different biomass yield and energy values as well as by their concentration of cellulose, hemicellulose and lignin. In the study the number and height of stems as well as the dry weight, ash and water mass fraction of biomass were estimated. The study was performed on Miscanthus plants propagated from rhizomes obtained from two different locations in Poland (Zabierzów – Z and Radzików – R), and on regenerants (Iv) obtained from Z plants. The results indicated that somaclonal variation occurs in M. × giganteus cultures and that regenerants show low polymorphic variation compared to donor plants. Plants propagated in an in vitro culture showed the lowest stem height, but the highest number of stems per plant. Dry matter yield was greatest in the R group, while regenerants demonstrated the highest level of hemicellulose fraction and lowest cellulose and lignin concentration. Energy value was the highest for Z plants, but Iv plants showed energy values on the same level as those of R plants. The data suggest that in vitro-propagated plants may be a source of new Miscanthus forms. 相似文献
65.
研究了混凝土暴露在重金属环境中的污染特征,采用Zn、Cu、Pb、Cr、Cd单一溶液及混合溶液浸泡C20混凝土试块,分析了重金属在混凝土剖面的分布规律。结果表明,重金属主要分布于混凝土表层1 cm内,1cm深度混凝土中重金属含量接近背景含量,建议在受重金属污染的混凝土构筑物拆除无害化处理处置中,可对其进行表层剥离。 相似文献
66.
67.
本文介绍了电信行业经营分析系统的作用、特点以及I3DSS的优点,提出了引入I3DSS的电信行业经营分析系统软件体系结构,并给出了基于该体系结构实现分析型应用的具体过程.国内某电信运营企业在建设其经营分析系统时已采用了本文的研究成果.实践证明,这些研究成果具有一定的推广应用价值. 相似文献
68.
为进一步研究基于UWB的无线定位技术,文中设计了一种基于UWB定位系统硬件平台。硬件平台基于模块式设计思路,选用STM32F405作为主控制器,通过SPI总线与DW1000射频芯片通信。UWB射频电路围绕DW1000设计布局,使用全向外置天线。硬件平台在通信方面设计使用GPRS无线通信模块并采用TOA定位方式,预留GPIO外设扩展接口。经制板测试,在视距空旷环境下最远通信距离为110m,在相同环境下100m测距均方根误差20.2cm,室内非视距环境中定位误差为20cm,满足室内高精度定位技术研究需求。 相似文献
69.
结合ERP的特点,首先阐述了ERP的在决策支持上面的缺陷,而后从商业智能的理论出发。给出了BI与ERP集成的体系结构以及相应的系统解决方案。分别阐述了商业智能中的数据仓库、OLAP、数据挖掘等方面的功能以及具体应用方法,为企业更好的利用ERP资源、完成决策、提高企业竞争力提供了一种较为经济的方式。 相似文献
70.
Variations of a passive safety containment for a BWR with active and passive safety systems 总被引:1,自引:0,他引:1
The paper presents variations of a certain passive safety containment for a near future BWR. It is tentatively named Mark S containment in the paper. It uses the operating dome as the upper secondary containment vessel (USCV) to where the pressure of the primary containment vessel (PCV) can be released through the upper vent pipes. One of the merits of the Mark S containment is very low peak pressure at severe accidents without venting the containment atmosphere to the environment. Another merit is the capability to submerge the PCV and the reactor pressure vessel (RPV) above the core level by flooding water from the gravity-driven cooling system (GDCS) pool and the upper pool. The third merit is robustness against external events such as a large commercial airplane crash owing to the reinforced concrete USCV. The Mark S containment is applicable to a large reactor that generates 1830 MW electric power. The paper presents several examples of BWRs that use the Mark S containment. In those examples active safety systems and passive safety systems function independently and constitute in-depth hybrid safety (IDHS). The concept of the IDHS is also presented in the paper. 相似文献