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采用天然二氧化锰和植物油酸、松香制备了新型有机金属催干剂,该催干剂能完全替代钴、铅等传统催干剂而单独用于涂料中。研究了天然二氧化锰的种类、聚合温度、反应时间对催干剂性能的影响,研究了催干剂用量对醇酸磁漆干燥性能和贮存稳定性等性能的影响,结果表明该催干剂的工艺稳定、操作方便、性能优良,综合效益显著。 相似文献
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多糖是自然界中储量最大的天然高分子,其分子链通常具有结构上的两亲性,能够较好地吸附在相界面上并表现出改善固-液、液-液之间相容性的能力。 此外,多糖独特的理化结构使其在溶液中具有良好的流变学性质以及形成凝胶网络的能力,使多糖能够在较低表面活性下体现出较好的界面吸附能力,常被用于多相体系的乳化、分散、增稠和稳定。通过化学改性可对天然多糖进行亲水-疏水平衡,并赋予其一定的化学活性、表面电荷、流变性能等,能够获得性能更加优异的绿色大分子表面活性剂。基于此,该文主要介绍了多糖在表面活性剂中的应用,主要包括纤维素、淀粉、半纤维素、甲壳素、天然树胶等,并从多糖独特的理化性质、结构以及改性特点出发,剖析其对乳化、分散、破乳、增溶等表面活性作用的影响,阐述多糖及其衍生物在表面活性剂中的研究进展及应用潜力。 最后,对多糖表面活性功能增强改性的发展方向进行了展望。 相似文献
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本文对天然香料的抗氧化性、主要抗氧化成分、制取方法、种类和使用等进行了阐述。实验结果表明,天然香料的某些性能优于BHA、BHT或VE,天然香料是食品等的优良抗氧化剂。 相似文献
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以天然石英粉、红丹、红矾钠为原料制得橙红色碱式硅铬酸铅颜料,其防锈性能优,是红丹的替代产品。介绍了制备该颜料的配方、生产工艺,并列举了颜料及其制漆的性能指标。讨论了焙烧温度和焙烧时间对颜色的影响。 相似文献
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为解决破乳剂的选择性强、破乳效率低的问题,采用化学破乳剂和微生物破乳剂复合的方法,研制出了广谱、高效、低成本的破乳剂,并用大庆三次采油采出液、塔河原油、南阳原油、蓬莱原油、俄罗斯混合原油进行了脱水、脱盐评价。结果表明:对于大庆油田采出液,微生物复合与化学破乳剂比较,脱水效率提高5%以上,脱出水含油可降低40%以上;对于易乳化的南阳原油、蓬莱原油,脱后含盐可达3 mg/L以下,脱出水含油可降低50%以上。工业应用表明:对于俄罗斯混合原油脱后含盐可达2 mg/L以下,脱出水含油可降低70%以上,脱后排水含油小于15 mg/L。所研制的微生物复合破乳剂适应性强,成本可降低20%~50%。 相似文献
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A minor lignan, 4ˊ-demethyldeoxypodophyllotoxin, was isolated from Sinopodophyllum emodi. First, a crude extract of S. emodi was analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS) to confirm the presence of the target compound. Then, the target lignan was successfully enriched in the crude extract precipitate by medium-pressure LC (MPLC) with high recovery (85%). Finally, an efficient separation was achieved by high-speed counter-current chromatography (HSCCC) using a two-phase solvent system of n-hexane-ethyl acetate–methanol–water (1:1:1:1, v/v/v/v). These results clearly demonstrate that the combination of HPLC-MS, MPLC, and HSCCC could be a powerful technique for the rapid screening, enrichment, and separation of minor compounds from complex natural products. 相似文献
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对原油在地表污染后的清理进行了综述,发现目前对原油污染地表的清理都会对地表造成不同程度的伤害。在原有专利技术的基础上,研究了无污染处理原油在地表的污染,并合成了用于原油污染地表土的清理剂,该化合物不仅能够使原油在地表脱附,而且能防止粘土的吸水、吸油膨胀引起的土壤伤害。分离出的原油不会在水中分散从而形成难以分离的油水乳状液,避免因清洗原油而引起污染,达到无伤害处理原油污染地表土的目的。 相似文献
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泰拉菌素的合成工艺改进 总被引:1,自引:0,他引:1
以阿奇霉素A(Ⅰ)为原料,经苄氧羰酰氯保护2'位羟基得到保护的阿奇霉素A(Ⅱ),然后经Albright-Goldman方法氧化4″位羟基得到Cbz保护的酮(Ⅲ),酮通过Wittig-Horner反应得到保护的烯(Ⅳ),烯经双氧水氧化得到保护的环氧化合物(Ⅴ),保护的环氧化合物在Pd/C催化下脱保护得到脱保护的环氧化合物(Ⅵ),脱保护的环氧化合物与正丙胺反应开环得到泰拉菌素粗品,粗品泰拉菌素成磷酸盐纯化,最后解析得到泰拉菌素(Ⅶ),总收率为42.0%,经HPLC测定w(Ⅶ)=98.0%。该法改进了文献合成方法,不需采用极低温反应。 相似文献
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Jin-Kwang Bok Heeman Lee Jay Woo Chang Sunwon Park 《Korean Journal of Chemical Engineering》2002,19(4):545-551
This paper presents a hybrid refinery scheduling system combining mathematical programming model and expert system. Mixed-integer
linear programming models for crude oil movement between units are merged into the expert system that is for qualitative issues
concerning crude vessel unloading operations. The target problem ranging from the crude unloading to the crude charging to
distillation towers is decomposed into several module problems for efficiency. Compared with existing scheduling approaches
for oil movement, the proposed hybrid refinery scheduling system is very effective in dealing with timing decisions involving
vessel unloading operations due to the advantages of an expert system. Since the proposed scheduling system can generate solutions
so fast, it is expected to play a key role in the real processes.
This paper is dedicated to Professor Wha Young Lee on the occasion of his retirement from Seoul National University. 相似文献
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Lei Wang Quanming Peng Shuzhen Li Liucheng Du Haijun Cai 《Journal of Industrial and Engineering Chemistry》2013,19(2):655-658
A study has been carried out for simultaneous desulfurization and demetalization by electric desalting from crude oil based on the oxidation of alkyl thiophene and nickel compounds with the compound of Chitosan Schiff Base under the condition of microwave irradiation (SDDM). Besides, an investigation has been made about the influence of Chitosan Schiff Base compound dose, initial temperature, and microwave time on desulfurization and demetalization. By using the optimized conditions for SDDM, up to 56% of sulfur and 82% of nickel removal rates were achieved for model compounds in crude oil samples. With the same conditions but without microwave the removal efficiency was lower than 56% for sulfur model compound and than 82% for nickel porphyrin in crude oil samples. Additionally, in order to develop a fundamental understanding of the SDDM mechanism of sulfides, a molecular simulation of sulfur compounds was performed with both the Hartree–Fock (HF) and second-order Moller–Plesset (MP2) levels of theory for the calculation of reaction kinetic rate by using Gaussian 03 program package. In comparison with conventional desulfurization and demetalization technology, the proposed SDDM process can accomplish the simultaneous removal of sulfur and nickel compounds from crude oil under relatively mild conditions. 相似文献
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目标成本管理是符合石油企业自身特点的成本控制方法。在实证研究的基础上,分析了原油目标成本管理的基本思路及运行机制,提出了原油目标成本管理的实施步骤及相应措施。 相似文献
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为了考察SbSn金属间化合物的制备条件对材料的结构以及脱硫性能的影响,采用不同的熔融温度,配以喷雾快冷法制备了SnSb金属间化合物.用差热分析和XRD对产物进行了测试表征.对产物的结构进行了模拟计算与讨论,给出了产品制备温度分别在750℃和950℃下的分子点群示意图.发现锡锑化合物在升温过程中,熔体的结构会发生变化,不同熔融温度下制备出的材料的晶体结构不同.脱硫实验结果表明,900℃以上熔融喷雾快冷制备出的材料具有较好的脱硫性能.在SnSb和原油乳化液质量比为1∶20的条件下,950℃下,熔融喷雾快冷制备出的材料一次搅拌24 h可以使原油中的硫含量降低2440.0 μg·g-1. 相似文献