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我捧着和冰心老人的合影照片,重读着她在照片背面给我的题词:“有了爱便有了一切冰心”冰心走了,她哼着《平安歌》叩开兔年大门后,平静而去,安祥而归,只把对祖国、对人民、对世界、对人类、对自然、对亲人、对故乡、对师生、对朋友、对少年儿童……精深的爱永留在了人间…… 相似文献
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《精细化工》2000,17(1):100-102
反式对氨基环己醇是合成祛痰药氨溴素的中间体,已报道的合成路线是以对乙酰氨基苯酚为原料,经加氢后,采用结晶法或柱分离法分离顺反对乙酰氨基环己醇,所得到的反式对乙酰氨基环己醇水解后可得到反式对氨基环己醇,总反应收率为27%(相对于对乙酰胺基苯酚的物质的量收率)。利用反式对氨基环己醇可以和丙酮反应生成席夫碱的原理分离顺反异构体,50
g 对乙酰氨基苯酚在170 ℃,9.0 MPa,5 g骨架镍的条件下加氢,产品用40
g的氢氧化钾水解,得到34.8 g顺反混合的对氨基环己醇,该混合物与200
mL丙酮反应,然后经水解,萃取,得到18.7 g反式对氨基环己醇,熔点112~114
℃,反式对氨基环己醇的总收率45%(相对于对乙酰氨基苯酚的物质的量收率)。 相似文献
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掺杂聚对苯撑的导电性能与结构 总被引:1,自引:0,他引:1
选用FeCl_3·6H_20作为掺杂剂对聚对苯撑进行掺杂,获得导电的聚对苯撑。讨论了掺杂时间和温度对其电导率的影响,并借助元素分析、红外光谱、电子自旋共振波谱等方法对掺杂前后的聚对苯撑的结构进行了研究,红外光谱分析发现掺杂后有新的吸收峰出现,电子自旋共振波谱分析证实掺杂聚对苯撑中有未成对自由基存在,同时,对掺杂机理进行了初步探讨。 相似文献
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我国脂肪酸的生产和应用 总被引:3,自引:0,他引:3
陆蠡珠 《精细与专用化学品》2007,15(1):24-28
简要介绍脂肪酸的分类、原料来源、生产工艺、品种以及用途。并对我国脂肪酸的生产现状进行了分析。重点介绍了脂肪酸在我国橡胶工业中、塑料助剂等领域的应用,脂肪酸甲酯作为表面活性剂在不同领域的广泛应用,最后还简述了癸二酸和改性醇酸树脂应用。 相似文献
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采用离子色谱法同时测定环境样品中的甲酸、乙酸、氯乙酸,简便快速,准确性较好,灵敏度较高。甲酸、乙酸、氯乙酸的检出限依次为0.030,0.096,0.574μg/mL(S/N=3),在1~20μg/mL浓度范围内均呈现良好的线性关系,相关系数(r)均大于0.998。将三种目标物定量加入到空白水样中,甲酸、乙酸、氯乙酸加标回收率均在95.04%~105.46%范围内,其RSD值均在1.65%~3.12%之间。结果表明,该法可应用于雨水、地下水、地表水等环境样品中甲酸、乙酸和氯乙酸的测定。 相似文献
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Claudio Guilherme Portela de Carvalho Luana Fernanda Mazzola José Marcos Gontijo Mandarino Flávio Carlos Dalchiavon José Lopes Ribeiro Aluisio Brigido Borba Filho Alberto Donizete Alves 《Journal of the American Oil Chemists' Society》2019,96(9):1019-1025
This study aimed to verify whether the fatty acid profiles of mid-oleic genotypes grown in the tropical region of Brazil fit the Codex Alimentarius and to examine the possibility of using traditional inbred lines to produce high-oleic hybrids. For this purpose, we assessed the fatty acid profile of six mid-oleic hybrids grown in environments with different minimum temperatures during oil formation in the achenes. The tests were conducted between 2015 and 2017 in an experimentally randomized complete block design with four replications. The oleic, linoleic, palmitic, and stearic acid contents were determined using gas chromatography. The mid-oleic hybrids presented varying levels of fatty acids, with oleic acid ranging between 43.6% and 84.6%, linoleic acid between 8.5% and 45.6%, palmitic acid between 3.9% and 5.7%, and stearic acid between 2.2% and 6.2%. Some of the fatty acid values were outside the ranges established by the CODEX STAN 210-1999 and were characteristic of high-oleic type sunflowers. This finding shows that we can take advantage of the potential of combining traditional inbred lines to produce high-oleic hybrids for faster and more economical breeding programs in these environments. 相似文献
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Voltammetric studies of Mn(II) were carried out in acetic acid (AA), trifluoroacetic acid (TFA), butyric acid (BA), perfluorobutyric acid (PFBA) and methanesulphonic acid (MSA) media. Influence of anodic limit and the nature of acids were investigated. Oxidation of Mn(II) shows two anodic peaks in weak acids namely acetic acid and butyric acid media due to the formation of insoluble Mn(III) and Mn(IV) species. Reduction of these species were also observed as two peaks in the cathodic region. Formation and reduction of solid oxide phases are the dominant electrode processes in such weak acid media. In strong acids like MSA and TFA media sharp anodic and cathodic peaks were obtained due to the formation and reduction of stable soluble Mn(III) species. SEM studies reveal the formation of thicker oxide phases in weak acid media and much thinner oxide layers in strong acid media. γ-MnO2 phase was formed from AA and TFA while -MnO2 phase was formed from BA and PFBA, suggesting a relationship between phase structure and anionic size. 相似文献
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介绍了不锈钢设备与零部件各种酸洗配方,特别对HNO3+HF、HNO3+HCl等混酸及酸洗膏的配方作了分析讨论。 相似文献