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固相合成法是胸腺五肽生产的主流技术。本文采用对碱敏感的Fmoc保护Na-氨基。用二甲基甲酰胺为溶剂合成胸腺五肽。本文阐述了其基本原理、采用此法的原因、合成工艺及纯化方法。 相似文献
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Upon promoting MgO (prepared via a sol-gel process) with any binary mixture of the alkali metal chlorides, catalytic systems are obtained which are more active, selective and much more stable with time-on-stream than the respective monoalkali promoted MgO in the oxidative coupling of methane (OCM) to C2 hydrocarbons. The best catalytic performance is obtained over (5 mol% NaCl+5 mol% CsCl)/MgO, which exhibits a C2 yield of 19.7% compared to 5.9 and 4.1% over 10 mol% NaCl/MgO and 10 mol% CsCl/MgO, respectively, at atmospheric pressure, a temperature of 750 °C, a space velocity of 15000 cm3 g–1 h–1,
= 608 Torr and CH4/O2 = 4. A series of different combinations among the five alkali chlorides were made and the afore-mentioned synergistic effect was always observed. The basicity and base strength distribution of the bialkali chloride systems (measured by the gaseous acid adsorption or benzoic acid titration methods) are significantly higher than those of the respective monoalkali halide systems. The relationship between the catalytic performance and basicity/base strength distribution is explored. 相似文献
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介绍了近年来1,1-二氨基-2,2-二硝基乙烯(FOX-7)的合成与应用、相转变、热性能、衍生物及相关理论研究等方面的研究成果.FOX-7具有优良的综合性能,与火药和炸药主要组分相容性良好,可应用于低敏感火药和炸药的研制;其分子中的硝基和氨基赋予了它良好的反应性,为新型含能材料的开发开辟了新途径;在不同的实验条件下,F... 相似文献
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Synergistic effect of 2-mercapto benzimidazole and KI on copper corrosion inhibition in aerated sulfuric acid solution 总被引:4,自引:0,他引:4
2-Mercapto benzimidazole (MBI) was used as a copper corrosion inhibitor in aerated 0.5 mol L–1 H2SO4 solutions. The inhibition efficiency (IE) increased with increasing MBI concentration to 74.2% at the 1 mM level. A synergistic effect existed when MBI and iodide ions were used together to prevent copper corrosion in sulfuric acid. It was found that IE reached 95.3% in 0.5 mol L–1 H2SO4 solutions containing 0.75 mmol L–1 MBI and 0.25 mmol L–1 KI. X-ray photoelectron spectroscopy (XPS) analysis of the copper samples showed that a (Cu+MBI) complex film formed on the surface to inhibit the copper corrosion and the iodide ions did not participate in the formation of the inhibitor film. The synergistic effect was attributed to the adsorption of iodide anions on the copper surface, which then facilitated the adsorption of protonated MBI and the formation of an inhibitive film. 相似文献
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硼酸锌在膨胀型无卤阻燃ABS中的协同作用 总被引:1,自引:0,他引:1
采用熔融共混法制备了丙烯腈-丁二烯-苯乙烯共聚物(ABS)/膨胀型阻燃剂(IFR)/硼酸锌(ZB)无卤阻燃复合材料。利用热重分析仪、氧指数测定仪、扫描电子显微镜等研究了ZB对复合材料热失重行为、阻燃性能、微观结构及力学、加工性能的影响。较低含量的ZB与IFR存在较好的阻燃协同作用,且ZB可促进IFR成炭,使ABS/IFR复合材料的氧指数及其残炭量分别由未加ZB时的27.4%、21.29%提高到30.1%和23.05%。ZB的加入能够提高ABS/IFR复合材料的弯曲性能和加工性能,但对复合材料的冲击、拉伸性能产生了不利影响。 相似文献