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《化学与粘合》2016,(6)
以C8-10醇和环氧乙烷为原料,反应合成了六聚氧乙烯醚,再与苯基缩水甘油醚形成加合物,苯基缩水甘油醚加成物与马来酸酐进行酯化反应形成产物苯基缩水甘油醚加成物马来酸单酯,并考察了反应条件。实验表明,在C8-10醇与环氧乙烷物质的量比为1∶6,压力为0.5MPa,反应温度150℃条件下反应,环氧乙烷结合率大于98%;六聚氧乙烯醚与苯基缩水甘油醚物质的量比为1∶1,催化剂三氟化硼乙基络合物为反应原料总物质的量的0.4%,温度50℃,反应时间45min,加合物收率达到91.6%;加合物与马来酸酐物质的量比1∶1,催化剂三正丁基胺为原料的1%(wt),反应时间4h,反应温度90℃,加合物马来酸单酯的收率达99%。 相似文献
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研究了黄腐酸(FA)作为一种的新的络合剂,与羟丙基-β-环糊精络合物(Hp-β-CD)相比,对阿司匹林(ASA)分解的影响。ASA与FA以1:0.5、1:1、1:2(物质的量比)络合,并用冷冻干燥、溶剂蒸发和喷雾干燥三种方法进行干燥。ASA-羟丙基-β-环糊精(1:1)络合物通过喷雾干燥制备,并与最佳FA络合物进行比较。将所有的络合物和ASA放入贴好标签的铝塑小包中密封,在温度为40±2℃、相对湿度为75%±5%的稳定暗箱中存放120d。分别在0、30d、60d、90d和120d分析各样品的水杨酸含量。以物质的量比为1:1进行络合的ASA-FA喷雾干燥络合物中水杨酸含量为4.31%,该络合物在所有不同制备方法的络合物中具有最佳稳定性。然而,1:1的ASA-羟丙基-β-环糊精喷雾干燥络合物中测得水杨酸含量只有2.35%。与FA相比,ASA与羟丙基-β-环糊精络合,其稳定性更强。为提高阿司匹林的稳定性,对一种新型FA络合剂进行了研究。与1:1ASA-FA喷雾干燥络合物相比,ASA与羟丙基-β-环糊精1:1络合时,ASA的稳定性有显著改善。 相似文献
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《化学世界》2015,56(1)
以三(2-羟乙基)异氰尿酸酯(赛克,THEIC)、四氯化硅与环氧丙烷为原料,合成有机硅酸酯阻燃剂赛克三硅酸氯丙酯。探讨了溶剂、反应温度与物质的量比对产品收率的影响。优化的工艺条件为:四氯化硅、环氧丙烷、赛克和环氧丙烷物质的量比为3∶6∶1∶3.5;四氯化硅先与环氧丙烷在35℃反应1h,而后加入赛克于85℃反应9h,再滴入环氧丙烷于60℃反应4h;产品收率为93.8%。采用FT IR、1 H NMR、差热与极限氧指数技术表征了产品的结构及阻燃等性能;应用实验表明该产品有较好的协同阻燃增效作用,可用于聚氯乙烯、聚氨酯、环氧树脂和不饱和树脂等高分子材料等阻燃剂。 相似文献
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固体超强酸催化剂在合成癸二酸二异辛酯反应中的研究 总被引:3,自引:0,他引:3
选用固体超强酸SO2 -4 ZrO2 -TiO2 催化合成癸二酸二异辛酯 ,制备该催化剂的最优条件为 :钛锆物质的量比为 7∶1,用浓度为 0 .5mol·L- 1 硫酸浸渍 ,5 5 0℃焙烧 3h ;使用该催化剂合成癸二酸二异辛酯的最佳反应条件为 :醇酸物质的量比为 3.0∶1,催化剂用量 3.5g moL ,反应时间 4h ,酯化率达 99.4 %。 相似文献
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文章以腐殖酸为原料制得可溶性腐植酸钠,再以2-丙烯酰胺基-2-甲基丙磺酸、丙烯酰胺、丙烯酸和腐植酸钠为单体,采用过硫酸钾为引发剂,用水溶液聚合法合成了抗高温降滤失剂,通过设计正交试验得到最佳反应条件:m(2-丙烯酰胺基-2-甲基丙磺酸)∶m(丙烯酰胺)∶m(丙烯酸)∶m(腐植酸钠)=3∶2∶1∶4,引发剂所占反应物的质量分数为0.7%,反应温度为65℃,pH=7,通过钻井液流变性能及滤失性测试,结果表明合成的降滤失剂有较好的提粘切作用、较好的高温(200℃)降滤失性能、抗盐至饱和。 相似文献
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《化学与生物工程》2021,38(10)
以芒果苷和溴代正丁烷为原料,合成了正丁基取代芒果苷,并采用L_(16)(4~4)正交实验对合成工艺进行了优化;利用AutoDock Vina软件,对正丁基取代芒果苷与抗乙肝病毒相关靶点进行分子对接,预测其抗乙肝病毒活性。结果表明,在反应时间为4 h、反应温度为60℃、芒果苷与溴代正丁烷物质的量比为1∶6.0、芒果苷用量为1 mmol、缚酸剂碳酸钾用量为0.58 g的最优条件下,2次验证实验得到的正丁基取代芒果苷收率分别为177.42 mg和183.72 mg。正丁基取代芒果苷与抗乙肝病毒各靶点的结合能均低于-6.0 kcal·mol~(-1),其中与核心靶点HBV核蛋白的结合能最低(-8.7 kcal·mol~(-1)),各优势构象与原构象的均方根偏差(RMSD)均低于2?,对接结果可信度较高。通过分子对接预测了正丁基取代芒果苷的抗乙肝病毒活性,为该类化合物的进一步研究奠定了基础。 相似文献
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利用室内生物测定的方法研究了三种不同来源的水溶性煤基酸对六种除草剂 ( 2 ,4- D丁酯、草甘膦、巨星、禾大壮、乙草胺和百草枯 )生物活性的影响 .结果表明 :水溶性煤基酸对2 ,4- D丁酯、草甘膦和巨星的生物活性有明显的增效作用 ;加快了禾大壮的作用速度 ;对乙草胺的生物活性影响较小 ;却使百草枯失去了活性 .三种不同来源的水溶性煤基酸对除草剂生物活性的影响程度不同 ,经化学降解制备的水溶性煤基酸略高于从风化煤中直接提取的水溶性煤基酸 .通过水溶性煤基酸对溶液表面活性以及对除草剂渗透性的影响 ,初步探讨了水溶性煤基酸影响除草剂生物活性的机理 相似文献
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钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响 总被引:4,自引:0,他引:4
考察了间歇反应器中钙离子存在下腐殖酸分子在TiO2颗粒表面的吸附行为,进而以125 W (Emax=365 nm) 汞灯为中心光源,考察了钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响. 结果表明,在腐殖酸初始浓度C0=20 mg/L, [Ca2+]=80 mg/L, pH=7和TiO2=1 mg/ml实验条件下,经2.5 h的光催化反应,腐殖酸的脱色率为100%,氧化分解率接近100%,矿化率大于95%. 相似文献
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腐植酸对氮、磷、钾的吸附和解吸特性研究 总被引:9,自引:0,他引:9
通过研究风化煤腐植酸在不同pH值下对氮、磷、钾的吸附和解吸特性,得出结论:(1)在供试的各种pH值(4~8)条件下,随着氮、磷、钾初始处理浓度的增加,腐植酸对其吸附量和解吸量均呈上升趋势,但解吸率均呈下降趋势。(2)在不同pH值的介质溶液中,腐植酸对氮、磷、钾的吸附和解吸特性不尽相同。其中,在碱性条件下,腐植酸对氮的吸附和解吸作用较强;在酸性条件下,腐植酸对磷的吸附和解吸作用较强,而腐植酸对钾的吸附和解吸作用在中性条件下更易发生。(3)腐植酸对氮、磷、钾的等温吸附可用Linear、Langmuir和Freundlich 3个吸附方程来拟合,相关性达显著或极显著水平,但以Freundlich方程为最优。 相似文献
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Yamini Satyawali Tom Van de Wiele Hans Saveyn Paul Van der Meeren Willy Verstraete 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2007,82(8):730-737
BACKGROUND: An understanding of the structure of humic acids is essential for their degradation or physical removal from wastewaters. This work aims at targeting the reactivity of these molecules by modifying their properties. Structural alterations were carried out by electrolytically reducing the solution containing humic acid in an electrolytic cell to convert them into less polar structures. RESULTS: Overall it was observed that electrolytic reduction of humic acids strongly facilitated their further treatability. First, the reduced forms of humic acids exhibited improved adsorption on activated carbon. For 1 kW h of electrical energy consumed during electrolytic reduction, the additional chemical oxygen demand (COD) adsorbed was 60 g for a synthetic humic acid solution. Similarly, the additional COD adsorbed (kW h)?1 was found to be 35 g and 112 g for humic acid‐rich effluent and landfill leachate, respectively. In comparison with non‐reduced control samples, a 200‐fold decrease in the chloroform formation was observed when electrolytically reduced drinking water samples were supplemented with a chlorine dosage of 150 mg L?1. Moreover, an enhanced membrane flux was obtained with electrically reduced samples, indicating their improved membrane filterability. CONCLUSION: The electrolyzed humus species were characterized by analyzing their surface tension and particle size. This work addresses an alternative technology for the treatment of water streams containing humic acids. Copyright © 2007 Society of Chemical Industry 相似文献
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The saving and recycling of chemical substances, which may be hazardous to human health and ecosystems, constitute a desirable goal worldwide. It is important to use a natural polymer that has a highly specific function and an environmental friendliness. In this study, humic acid was added to a natural polymer, a pectin membrane, and a hydrophobic poly(1‐trimethylsilyl‐1‐propyne) (PMSP) membrane to enhance the affinity for phenol or aniline. Also, the separation performance, based on the membrane materials and methods of addition, was investigated. The effect of the adsorption of phenol and aniline by humic acid was investigated. A high rate of aniline adsorption was observed. The interaction of the humic acids and the aniline was mainly observed by polar bonding. For the PMSP membrane with humic acid added to the surface, the humic acid exists in a colloidal state. During pervaporation, the permeation of water was prevented by the adsorbed solute. Because the permeability of aniline increased and the permeability of water significantly decreased, the PMSP membrane with humic acid added to the surface had a high permeate aniline concentration, and the permselectivity was improved. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 461–468, 2004 相似文献
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《Fuel》1986,65(7):1012-1016
The variation of the metal complexing ability of humic acids with the rank of the parent coal was investigated by determining the conditional stability constants of complexes formed between cupric ions and humic acids from several coals. Humic acids were extracted from four Spanish coals varying in rank from peat to subbituminous coal. The stability constants were determined at pH 5.0 and μ = 0.1 by a modified version of Schubert's ion exchange method. The stability of the metal-humic acid bonds decreases with the rank of parent coal. The stoichiometry of the complexes tends to 1:1 with increasing coalification of humic acids. The influence of oxidative conditions of extraction on the conditional stability constants of complexes was also examined and it was found that they do not affect significantly the elemental composition or the metal complexing ability of regenerated humic acids. 相似文献