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栀子是茜草科栀子属植物,是药食两用植物,其果实具有清热解毒等多种功效。其主要化学成份有环烯醚萜类、有机酸(酯)、黄酮、香豆素、挥发油等。文章主要对栀子的环烯醚萜类及单萜苷类化学成份及其药理活性作一综述。 相似文献
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2009年7月,一种新型生物杀虫剂VIR—EX在巴西隆重上市。该产品以棒状病毒为基础,可防控甜菜夜蛾。Almefia蔬菜与水果联合委员会和Andalusiam农业委员会的农业培训和发展委员会(IFAPA)上个月达成了价值10.83万欧元的协议。 相似文献
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严振邦 《化工自动化及仪表》1981,(7)
由赫尔蒂公司设计的引进装置共设计了37台分析仪表。工艺流程配置仪表见附表。这些仪表基本上是在线开环分析,部分附有报警、联锁功能。从三个工厂开车到生产的二年多实践来看,这些分析仪表能满足工艺生产要求,分析仪表在生产上作用有较好的体现。本文仅这些分析仪表在实际投运中所起作用,以及使用中存在问题作一扼要总结供 相似文献
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Song木属植物是目前天然产物化学中研究较多的一类植物,此文介绍了我国在Song木属植物种类、分布、化学成分其药理活性等方面的研究进展,并给出了近年来新分离的化合物的名称手结构骨架。 相似文献
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Preventing the corrosion of metal substrates by applying an active coating was studied. The active coating was prepared by addition of metal powder and polyaniline in xylene solution. Trials were conducted by coating a blast-cleaned, mild steel round bar with a brush. The coating was dried in the air and the steel samples were immersed in water collected from the open sea. Open circuit potential of steel was measured with silver/silver chloride reference electrode. The potential in seawater was in the range of — 740mV to — 956mV, indicating complete protection of steel against corrosion. This potential meets the criteria for protection as per clause 5.4.1 of Det Norsk Veritas Recommended Practice RPB 401 (1993), page 8.1 The active coating system can be used for protecting the steel against corrosion in marine and any other highly corrosive environment. Accelerated tests in accordance with ASTM D5894 — 962 with freeze cycle developed by U.S. Federal Highway Administration are planned. 相似文献
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为了分析腰果酚中的有效成分,采用红外光谱仪(IR)对腰果酚进行初步定性;然后采用气相-质谱联用仪(GC/MS)对腰果酚有效成分进行有效分离和准确定性。色谱柱:DB-5柱(30mm×0.25mm×0.25μm);溶剂:氯仿;柱温:起始温度210℃(保持3.0min),升温速率1℃2/min,最终温度230℃(保持3.0min)。在此条件下,腰果酚中的有效成分可以较好的分离。 相似文献
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Ming Zhang Ai-Qin Zhang Rongli Zhang Shu-Hua Yang Yu-Jie Hong 《Catalysis Letters》2008,124(1-2):146-149
Highly active catalysts composed of titanocene complexes and nanometric sodium hydride have been developed for the hydrogenation of styrene under normal pressure. The highest initial catalytic activity reached 138 s?1 (average value in the first 1 min), which is higher than previously reported data for the hydrogenation of styrene. The highest number of catalytic turnover reached 21,700 in 2 h. An effect of steric hindrance of substituents of titanocene complexes on the catalytic efficiency was observed. 相似文献
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天然产物活性组分的糖基化修饰研究进展 总被引:2,自引:0,他引:2
天然产物广泛存在于自然界中,其数量种类繁多且结构复杂多样,具有许多生理与药理活性。糖基化修饰能增加天然产物结构和功能的多样性,已成为当今新药开发的研究热点。文章归纳了不同结构类型的天然产物糖基化修饰的国内外研究现状与特点,并从糖的连接位置、数量及种类等方面描述糖基化修饰对天然产物水溶性、药理活性和生物利用率等方面的影响,为天然产物糖基化的开发与应用提供参考。 相似文献
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This paper reviews the synthesis and characterization of several transparent glass-ceramics with optical active nanocrystals. Glass-ceramics containing ferroelectric SrxBa1-xNb2O6 nanocrystals with an ellipsoidal shape show optical phase modulations in the presence of alternative electric fields. In the glass-ceramics with Ba2TiSi2O8 (BTS) nanocrystals, BTS crystalline layers with a thickness of approximately 120 nm are formed at the surface and ellipsoidal-shaped crystallites with a diameter of 100–200 nm are dispersed in the glass matrix. Some TeO2-based and GeO2-based glasses show a prominent nanocrystallization. RE-doped CaF2 nanocrystals are patterned in a spatially selected region by laser irradiations. The size, morphology, and dispersion state of nanocrystals should be carefully checked in each glass system and composition. The basic concept for the design of glass system and composition is also discussed. Some data on optical active performances in transparent glass-ceramics with nanocrystals were introduced. 相似文献
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