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乙酸正丁酯的实验室合成条件优化研究
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作者 邹静 《化学工程师》 CAS 2024年第3期14-18,共5页
以冰醋酸和正丁醇为原料,浓H_(2)SO_(4)作催化剂,无水Mg SO4为干燥剂合成乙酸正丁酯,研究了投料比、反应时间、反应温度、浓H_(2)SO_(4)用量等对产率和纯度的影响。得出最佳反应条件为:冰醋酸与正丁醇的物质的量之比为1∶1.05,冰醋酸的... 以冰醋酸和正丁醇为原料,浓H_(2)SO_(4)作催化剂,无水Mg SO4为干燥剂合成乙酸正丁酯,研究了投料比、反应时间、反应温度、浓H_(2)SO_(4)用量等对产率和纯度的影响。得出最佳反应条件为:冰醋酸与正丁醇的物质的量之比为1∶1.05,冰醋酸的用量为14.00g,浓H_(2)SO_(4)用量为1.00m L,回流反应时间为40min。在该条件下合成乙酸正丁酯,纯度超过98%,产率可达80%以上。 展开更多
关键词 乙酸正丁酯 冰醋酸 正丁醇 合成 条件优化
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臭氧化法制备N-Boc-(甲氨基)乙醛
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作者 张萍 李孝莉 +3 位作者 李贺 陈力荣 于醒醒 张珍明 《连云港职业技术学院学报》 2024年第1期1-6,共6页
以N-甲基烯丙胺和二碳酸二叔丁酯为原料,在乙醇中缩合得到N-Boc-甲基烯丙胺,再以乙酸乙酯为溶剂经臭氧臭氧化,用NaHSO_(3)还原分解,经萃取、蒸馏,制备N-Boc-(甲氨基)乙醛。采用L16(45)正交实验确定了最优臭氧化温度为5~10℃、反应时间为... 以N-甲基烯丙胺和二碳酸二叔丁酯为原料,在乙醇中缩合得到N-Boc-甲基烯丙胺,再以乙酸乙酯为溶剂经臭氧臭氧化,用NaHSO_(3)还原分解,经萃取、蒸馏,制备N-Boc-(甲氨基)乙醛。采用L16(45)正交实验确定了最优臭氧化温度为5~10℃、反应时间为3 h、臭氧流量为0.04 m^(3)/h,粗产物用乙醚萃取,获得目标产物收率78.7%,纯度99.2%(HPLC),并用IR、^(1)H NMR、^(13)C NMR和MS表征了产物的结构。 展开更多
关键词 N-Boc-(甲氨基)乙醛 N-甲基烯丙胺 二碳酸二叔丁酯 臭氧化
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N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺通过NLRP3/Caspase-1抑制巨噬细胞泡沫化及焦亡作用
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作者 舒志云 呼延子旭 +4 位作者 张文晴 谢世顺 成鸿源 徐国兴 李相军 《中国药理学通报》 CAS CSCD 北大核心 2024年第6期1035-1041,共7页
目的设计并合成了嘧啶并吲哚类衍生物N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺(BFPI),探讨其是否通过NLRP3/Caspase-1通路抑制巨噬细胞焦亡和泡沫化作用。方法以2,4,6-三乙氧羰基-1,3,5-三嗪和2-氨基吲哚为起始原料合成BFPI,并通过1H NMR... 目的设计并合成了嘧啶并吲哚类衍生物N-丁基-9 H-嘧啶并[4,5-b]吲哚-2-甲酰胺(BFPI),探讨其是否通过NLRP3/Caspase-1通路抑制巨噬细胞焦亡和泡沫化作用。方法以2,4,6-三乙氧羰基-1,3,5-三嗪和2-氨基吲哚为起始原料合成BFPI,并通过1H NMR、13 C NMR、ESI-MS对其结构进行表征。将体外培养的小鼠单核巨噬细胞株RAW264.7分为空白组、模型组(PA)组和治疗组(BFPI)组,各组细胞用对应培养液处理24 h后,用MTT法检测其增殖活力,油红O染色检测细胞内脂滴形成情况,并用Western blot和RT-qPCR检测NLRP3、Caspase-1和MCP-1 mRNA和蛋白表达水平。结果与空白组比较,模型组细胞增殖活力明显下降,脂滴形成量明显增加,与模型组比较,治疗组细胞增殖活力明显增加,脂滴形成量明显降低,差异均有统计学意义(P<0.01);与空白组比较,模型组细胞NLRP3、Caspase-1和MCP-1的mRNA和蛋白表达水平均明显增加,与模型组比较,治疗组细胞上述指标表达水平均明显下降,差异有统计学意义(P<0.01)。结论BFPI可通过抑制巨噬细胞NLRP3、Caspase-1和MCP-1的表达进而促进其增殖并抑制脂质吞噬能力,有助于延缓动脉粥化时巨噬细胞来源的泡沫细胞形成。 展开更多
关键词 N-丁基-9 H-嘧啶并[4 5-b]吲哚-2-甲酰胺 NLRP3 动脉粥样硬化 巨噬细胞 细胞泡沫化 细胞焦亡
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Di-(n-butyl)-phthalate-induced Oxidative Stress and Depression-like Behavior in Mice with or without Ovalbumin Immunization 被引量:5
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作者 ZUO Hao Xiao LI Jin Quan +5 位作者 HAN Bing KE Chen Juan LIU Xu Dong ZHANG Yu Chao LI Li YANG Xu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第4期268-280,共13页
Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups:saline;ovalbumin (OVA... Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups:saline;ovalbumin (OVA)-immunized;saline+DBP (0.45 mg/kg·183;d); saline+DBP (45 mg/kg·d); DBP (0.45 mg/kg·d) OVA-immunized; DBP (45 mg/kg·d) OVA-immunized; saline+hydrocortisone (30 mg/kg·d); and hydrocortisone (30 mg/kg·d)-exposed OVA-immunized. Behavior (e.g. open-field, tail suspension, and forced swimming tests), viscera coefficients (brain and spleen), oxidative damage [e.g. reactive oxygen species (ROS), malondialdehyde (MDA), and glutathione (GSH)], as well as levels of IgE and IL-4, were then analyzed. Results In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.Conclusion Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration. 展开更多
关键词 Di (n-butyl) phthalate Atopic allergy Depression MICE Oxidative stress Behavioral tests
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基于非靶向代谢组学研究邻苯二甲酸二丁酯对菜心代谢产物组成的影响 被引量:1
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作者 唐崇杰 冼陈洁 陈梦华 《农业环境科学学报》 CAS CSCD 北大核心 2024年第4期786-798,共13页
为研究邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)胁迫对菜心代谢产物组成的影响,本文基于非靶向代谢组学,通过主成分分析、偏最小二乘判别分析等多元统计分析方法,对DBP胁迫下菜心不同组织代谢产物的差异及其关键通路进行研究。结果... 为研究邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)胁迫对菜心代谢产物组成的影响,本文基于非靶向代谢组学,通过主成分分析、偏最小二乘判别分析等多元统计分析方法,对DBP胁迫下菜心不同组织代谢产物的差异及其关键通路进行研究。结果发现:不同DBP浓度胁迫下菜心不同组织存在明显差异的代谢产物有105种,主要分布在36条代谢途径中。P<0.05的代谢途径有3条,即色氨酸代谢(Tryptophan metabolism)、苯丙氨酸代谢(Phenylalanine metabolism)和丁酸代谢(Butanoate metabolism)。研究表明,基于非靶向代谢组学可直观反映DBP对菜心代谢产物组成的影响,为后续开发农作物关键通路上的靶向化学调控剂提供科学依据。 展开更多
关键词 非靶向代谢组学 邻苯二甲酸二丁酯(DBP) 菜心 不同组织 代谢产物
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Difluoromethylation of O-, S-, N-, C-Nucleophiles Using Difluoromethyltri(n-butyl)ammonium Chloride as a New Difluorocarbene Source 被引量:2
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作者 王飞 黄维洲 胡金波 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第12期2717-2721,共5页
Difluoromethyltri(n-butyl)ammonium chloride 1 was found to be an effective difluorocarbene reagent for O-, S-, N-, C-difluoromethylation under basic conditions. It is particularly remarkable that, when only 1.2 equi... Difluoromethyltri(n-butyl)ammonium chloride 1 was found to be an effective difluorocarbene reagent for O-, S-, N-, C-difluoromethylation under basic conditions. It is particularly remarkable that, when only 1.2 equivalent of reagent 1 was used, the difluoromethylated products were obtained in moderate to excellent yields. 展开更多
关键词 DIFLUOROCARBENE CF2H group DIFLUOROMETHYLATION difluoromethyltri(n-butyl)ammonium chloride
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亚硝酸叔丁酯与腈合成N-叔丁基酰胺的研究
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作者 钟西亚 刘春阳 +3 位作者 沈馨雅 王晓娇 何薇 李江胜 《精细化工中间体》 CAS 2024年第2期42-45,共4页
建立了一种腈在亚硝酸叔丁酯作用下经Ritter反应直接转化成N-叔丁基酰胺的方法。优化条件为:以三氟乙酸为催化剂,n(亚硝酸叔丁酯)∶n(苯甲腈)=1.5∶1.0,反应温度为65℃,1,2-二氯乙烷为溶液,反应8 h。优化条件下合成了15种N-叔丁基酰胺,... 建立了一种腈在亚硝酸叔丁酯作用下经Ritter反应直接转化成N-叔丁基酰胺的方法。优化条件为:以三氟乙酸为催化剂,n(亚硝酸叔丁酯)∶n(苯甲腈)=1.5∶1.0,反应温度为65℃,1,2-二氯乙烷为溶液,反应8 h。优化条件下合成了15种N-叔丁基酰胺,收率60%~87%。该方法条件温和、操作简单、收率较高。 展开更多
关键词 N-叔丁基酰胺 亚硝酸叔丁酯 合成
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外卖包装材料对我国青年群体暴露DBP和DiBP的影响
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作者 沈昊阳 陈立波 +6 位作者 张颖 鲁新宇 吴倩霆 马康维 王欣仪 马静 高崇婧 《浙江万里学院学报》 2024年第4期81-89,共9页
青年群体是外卖食品最大的消费群体,外卖包装材料中的污染物对青年群体的危害不容忽视。文章分析了外卖包装材料对我国青年群体暴露邻苯二甲酸二正丁酯(DBP)和邻苯二甲酸二异丁酯(DiBP)的影响,结果表明,发泡聚苯乙烯(PS)餐盒中DBP和DiB... 青年群体是外卖食品最大的消费群体,外卖包装材料中的污染物对青年群体的危害不容忽视。文章分析了外卖包装材料对我国青年群体暴露邻苯二甲酸二正丁酯(DBP)和邻苯二甲酸二异丁酯(DiBP)的影响,结果表明,发泡聚苯乙烯(PS)餐盒中DBP和DiBP的浓度(2986.27 ng/g和1345.20 ng/g)显著高于聚丙烯(PP)餐盒、纸质餐盒和锡纸餐盒,青年人群使用PS餐盒暴露DBP和DiBP的暴露量约为使用纸质餐盒和锡纸餐盒的2~5倍,青年人群经外卖餐盒暴露DBP和DiBP的暴露量占经饮食途径暴露DBP和DiBP暴露总量的1.72%~9.49%,占体内DBP和DiBP暴露总量的0.09%~0.47%。外卖包装材料是青年人群暴露DBP和DiBP的重要来源之一。 展开更多
关键词 邻苯二甲酸二正丁酯 邻苯二甲酸二异丁酯 外卖包装材料 暴露
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不同硫化体系对生物基衣康酸酯橡胶性能的影响
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作者 韩菊 郝福兰 +2 位作者 赵春财 牛淳良 郑红兵 《合成橡胶工业》 CAS 2024年第3期240-246,共7页
研究了传统硫化(CV)体系、半有效硫化(SEV)体系、有效硫化(EV)体系、过氧化物双叔丁基过氧异丙基苯(BIBP)/三烯丙基异氰脲酸酯(TAIC)硫化体系和酚醛树脂SP1045硫化体系对生物基衣康酸酯橡胶性能的影响。结果表明,BIBP/TAIC硫化体系硫化... 研究了传统硫化(CV)体系、半有效硫化(SEV)体系、有效硫化(EV)体系、过氧化物双叔丁基过氧异丙基苯(BIBP)/三烯丙基异氰脲酸酯(TAIC)硫化体系和酚醛树脂SP1045硫化体系对生物基衣康酸酯橡胶性能的影响。结果表明,BIBP/TAIC硫化体系硫化速率最快,而SP1045硫化体系硫化速率最慢,CV体系、SEV体系和EV体系硫化速率依次逐渐加快;硫黄硫化体系硫化胶的交联密度由大到小依次为:CV体系、SEV体系和EV体系;硫化胶拉伸强度由大到小依次为:SEV体系、SP1045硫化体系、CV体系、EV体系和BIBP/TAIC硫化体系,其中EV体系硫化胶的扯断伸长率和撕裂强度最大,CV体系硫化胶的耐磨性能最好;BIBP/TAIC硫化体系硫化胶具有最优的耐热氧老化性能;与硫黄硫化体系相比,BIBP/TAIC和SP1045硫化体系硫化胶玻璃化转变温度明显向高温方向偏移;CV体系硫化胶60℃时的损耗因子和滚动阻力均为最小;EV体系硫化胶的的有效阻尼温域最宽。 展开更多
关键词 衣康酸酯橡胶 硫化体系 硫化特性 物理机械性能 耐热氧老化性能 动态力学性能
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气相色谱法测定医用胶中α-氰基丙烯酸正丁酯和柠檬酸三乙酯的含量
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作者 梅炜华 吴小红 +1 位作者 汪家升 董芳芳 《当代化工研究》 CAS 2024年第5期64-66,共3页
目的:建立医用胶中α-氰基丙烯酸正丁酯和柠檬酸三乙酯含量的气相色谱测定方法。方法:气相色谱法:HP-5毛细管色谱柱;检测器:氢火焰离子化检测器;程序升温:初始温度100℃保持2min,以10℃/min的速率升温至180℃,保持3min;进样口温度:230℃... 目的:建立医用胶中α-氰基丙烯酸正丁酯和柠檬酸三乙酯含量的气相色谱测定方法。方法:气相色谱法:HP-5毛细管色谱柱;检测器:氢火焰离子化检测器;程序升温:初始温度100℃保持2min,以10℃/min的速率升温至180℃,保持3min;进样口温度:230℃;检测器温度:250℃;柱流速:2mL/min;进样量:1.0μL,分流比30:1。结果:α-氰基丙烯酸正丁酯在浓度0.10~0.60mg/mL范围内线性良好,线性方程为y=373.54589x+1.08702,线性相关系数为0.9997,准确度为98.8%~100.3%,精密度RSD为0.572%,定量限为1.20ug/mL;柠檬酸三乙酯在浓度0.02~0.12mg/mL范围内线性良好,线性方程为y=259.92943x-0.12898,线性相关系数为0.9995,准确度为100.1%~100.3%,精密度RSD为1.016%,定量限为3.0ug/mL。结论:本法可用于医用胶中α-氰基丙烯酸正丁酯和柠檬酸三乙酯含量的测定。 展开更多
关键词 气相色谱法 医用胶 Α-氰基丙烯酸正丁酯 柠檬酸三乙酯 含量
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合成乳酸正丁酯的催化精馏工艺研究
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作者 杜海明 《化工管理》 2024年第22期149-152,共4页
通过搭建微型催化精馏塔,以Hβ沸石作为催化剂,研究了乳酸和正丁醇在催化精馏塔中反应生成乳酸正丁酯和水的情况。实验考察了不同的酸醇进料比、乳酸进料空速、回流比、进料位置对酯化反应过程的影响,筛选出了最佳反应条件。
关键词 化学工艺 酯化反应 乳酸正丁酯 催化精馏
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乙酸正丁酯催化合成的条件探究
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作者 王蔓 李壮 +7 位作者 杨帆 陈聪地 余名胜 李臻 米园 周芹 叶佳鑫 陶果 《广州化工》 CAS 2024年第18期39-42,共4页
乙酸正丁酯在化工生产、医药等方面都有广泛的运用。本文采用四因素三水平的正交实验设计对硫酸铝钾、对甲苯磺酸、十二水合硫酸铁铵/过硫酸铵三类催化剂进行了实验选择,选出了硫酸铝钾作为催化剂。然后在该催化剂下,通过单因素实验法... 乙酸正丁酯在化工生产、医药等方面都有广泛的运用。本文采用四因素三水平的正交实验设计对硫酸铝钾、对甲苯磺酸、十二水合硫酸铁铵/过硫酸铵三类催化剂进行了实验选择,选出了硫酸铝钾作为催化剂。然后在该催化剂下,通过单因素实验法进一步探究了醇酸比、反应温度、反应时间分别对酯化率的影响。优化的合成条件为:催化剂采用硫酸铝钾,在醇酸比为1∶1、温度为125℃、反应时间为50 min时产率高达87.61%。催化剂重复使用四次后酯化率仍有70.03%。 展开更多
关键词 乙酸正丁酯 硫酸铝钾 醇酸比 催化剂 合成
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CO_2 capture from binary mixture via forming hydrate with the help of tetra-n-butyl ammonium bromide 被引量:22
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作者 Shifeng Li Shuanshi Fan +2 位作者 Jingqu Wang Xuemei Lang Deqing Liang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第1期15-20,共6页
Hydrate formation rate and separation effect on the capture of CO2 from binary mixture via forming hydrate with 5 wt% tetra-n-butyl ammonium bromide (TBAB) solution were studied. The results showed that the inductio... Hydrate formation rate and separation effect on the capture of CO2 from binary mixture via forming hydrate with 5 wt% tetra-n-butyl ammonium bromide (TBAB) solution were studied. The results showed that the induction time was 5 min, and the hydrate formation process finished in 1 h at 4.5 ℃ and 4.01 MPa. The hydrate formation rate constant reached the maximum of 1.84× 10^-7 molZ/(s.J) with the feed pressure of 7.30 MPa. The CO2 recovery was about 45 % in the feed pressure range from 4.30 to 7.30 MPa. Under the feed pressure of 4.30 MPa, the maximum separation factor and CO2 concentration in hydrate phase were 7.3 and 38.2 mol%, respectively. The results demonstrated that TBAB accelerated hydrate formation and enriched CO2 in hydrate phase under the gentle condition. 展开更多
关键词 CO2 CAPTURE HYDRATE tetra-n-butyl ammonium bromide
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Effects of di-n-butyl phthalate on male rat reproduction following pubertal exposure 被引量:8
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作者 Ai-Mei Bao Xiao-Ming Man +6 位作者 Xue-Jiang Guo Hui-Bin Dong Fu-Qiang Wang Hong Sun Yu-Bang Wang Zuo-Min Zhou Jia-Hao Sha 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第5期702-709,共8页
Di-n-butyl phthalate (DBP) is an endocrine-disrupting chemical that has the potential to affect male reproduction. However, the reproductive effects of low-dose DBP are still not well known, especially at the molecu... Di-n-butyl phthalate (DBP) is an endocrine-disrupting chemical that has the potential to affect male reproduction. However, the reproductive effects of low-dose DBP are still not well known, especially at the molecular level. In the present study, pubertal male Sprague-Dawley rats were orally administered DBP at a wide range of doses (0.1, 1.0, 10, 100 and 500 mg kg^-1 day^-1) for 30 days. The selected end points included reproductive organ weights, testicular histopathology and serum hormonal levels. Additionally, proteomic analysis was performed to identify proteins that are differentially expressed as a result of exposure to DBP at low doses (0.1, 1.0 and 10 mg kg^-1 day^-1). Toxic effects were observed in the high-dose groups, including anomalous development of testes and epididymides, severe atrophy of seminiferous tubules, loss of spermatogenesis and abnormal levels of serum hormones. Treatment with low doses of DBP seemed to exert a 'stimulative effect' on the serum hormones. Proteomics analysis of rat testes showed 20 differentially expressed proteins. Among these proteins, alterations in the expression of HnRNPA2/B1, vimentin and superoxide dismutase 1 (SOD1) were further confirmed by Western blot and immunohistochemistry. Taken together, we conclude that high doses of DBP led to testicular toxicity, and low doses of DBP led to changes in the expression of proteins involved in spermatogenesis as well as changes in the number and function of Sertoli and Leydig cells, although no obvious morphological changes appeared. The identification of these differentially expressed proteins provides important information about the mechanisms underlying the effects of DBP on male rat reproduction. 展开更多
关键词 di-n-butyl phthalate HORMONES PROTEOMICS SPERMATOGENESIS TESTIS
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Esterification of levulinic acid to n-butyl levulinate over heteropolyacid supported on acid-treated clay 被引量:10
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作者 S. Dharne V. V. Bokade 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第1期18-24,共7页
Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesi... Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid (HPA) supported on acid-treated clay montmorillonite (K10). 20% (w/w) dodecatungestophosphoric acid (DTPA) supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% (w/w) DTPA/K10 for optimization of the activity. 展开更多
关键词 levulinic acid N-BUTANOL dodectungestophosphoric acid K10 n-butyl levulinate
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Efficient one-pot synthesis of n-butyl levulinate from carbohydrates catalyzed by Fe_2(SO_4)_3 被引量:8
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作者 Ran An Guizhuan Xu +2 位作者 Chun Chang Jing Bai Shuqi Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期556-563,共8页
Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the cat... Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the catalysis of metal sulfates was developed. The catalytic activity of a series of metal sulfates for the synthesis of BL from fructose was investigated. Among various metal sulfates, ferric sulfate Fe(SO)was found to be the most efficient catalyst, which gave a remarkably high BL yield of 62.8 mol% under the conditions of 463 K, 3 h, a catalyst dosage of 5.0 g/L, and fructose concentration of 25 g/L. Different carbohydrates including glucose, cellulose, inulin and sucrose were also used for one-pot synthesis of BL with the catalysis of Fe(SO), showing the yields of 39.6, 30.5, 56.6 and 50.1 mol%, respectively. In addition,the recycling and reuse of Fe(SO)was studied by characterizing them using powder X-ray diffraction(XRD), scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS). A plausible reaction pathway for the one-pot synthesis of BL from fructose was proposed. This study provides a facile and feasible way for the synthesis of BL from biomass. 展开更多
关键词 ONE-POT n-butyl levulinate Metal sulfate Carbohydrates
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n-Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation 被引量:10
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作者 Yi Qun LI Xin Ming XU Mei Yun ZHOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期448-450,共3页
The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in mo... The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields. 展开更多
关键词 n-butyl pyridinium nitrate ionic liquid Knoevenagel condensation.
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Developmental Toxicity in Mice Following Paternal Exposure to Di-N-Butyl-Phthalate (DBP) 被引量:9
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作者 Malgorzata M.DOBRZY SKA Ewa J.TYRKIEL Krzysztof A.PACHOCKI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第5期569-578,共10页
Objective The aim of the present study was to investigate the effects of paternal Di‐N‐butyl‐phthalate (DBP) exposure pre‐ and postnatally on F1 generation offspring,and prenatally on F2 generation offspring.Met... Objective The aim of the present study was to investigate the effects of paternal Di‐N‐butyl‐phthalate (DBP) exposure pre‐ and postnatally on F1 generation offspring,and prenatally on F2 generation offspring.Methods Male mice were exposed to either 500 mg/kg or 2 000 mg/kg of DBP for 8 weeks,and mated with non‐exposed females.Three‐quarters of the females were sacrificed a day prior to parturition,and examined for the number of living and dead implantations,and incidence of gross malformations.Pups from the remaining females were assessed for developmental markers,growth parameters,as well as sperm quantity and quality.Results There were no changes in the fertility of parents and in intrauterine development of the offspring.Pups of DBP‐exposed males demonstrated growth‐retardation.Following paternal exposure to 500 mg/kg bw of DBP,there were almost twice the number of males than females born in the F1 generation.F1 generation females had a 2.5‐day delay in vaginal opening.Paternal exposure to 2 000 mg/kg bw of DBP increased the incidence of sperm head malformations in F1 generation males;however,there were no changes in the fertility and viability of foetuses in the F2 generation.Conclusion Paternal DBP exposure may disturb the sex ratio of the offspring,delay female sexual maturation,and deteriorate the sperm quality of F1 generation males. 展开更多
关键词 Di‐n‐butyl phthalate Paternal exposure Pre‐ and postnatal effects Male‐mediated developmental toxicity
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Removal of a type of endocrine disruptors—di-n-butyl phthalate from water by ozonation 被引量:7
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作者 LI Hai-van QU Jiu-hui LIU Hui-juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期845-851,共7页
Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration w... Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration were investigated. In addition, the activities of radicals on uncatalysed and catalysed ozonation were studied. The degradation intermediate products were followed and the kinetic of the ozonation were assessed as well. Results revealed that ozonation of DBP followed two mechanisms. Firstly, the reaction rate of direct ozonation was slower at lower pH, temperature, and ionic strength. Secondly, when these factors were increased for indirect radical reaction, higher percentage of DBP was removed with the increase of the initial ozone dosage and the decrease of the initial DBP concentration. In addition, tea-butanol, humic substances and Fe(Ⅱ) affected DBP ozonation through the radical pathway. It was determined that ozonation was restrained by adding tea-butanol for its radical inhibition effect. Furthermore, humic substances enhanced the reaction to some extent, but a slight negative effect would be encountered if the optimum dosage was exceeded. As a matter of fact, Mn(Ⅱ) affected the ozonation by "active sites" mechanism. In the experiment, three different kinds of intermediate products were produced during ozonation, but the amount of products for each one of them decreased as pH, temperature, ionic strength and initial ozone dosage increased. A kinetic equation of the reaction between ozone and DBP was obtained. 展开更多
关键词 di-n-butyl phthalate (DBP) OZONATION key impact factors reaction kinetics degradation intermediate products
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Cerebral and splenic infarctions after injection of N-butyl-2-cyanoacrylate in esophageal variceal bleeding 被引量:4
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作者 Dae-Seong Myung Cho-Yun Chung +5 位作者 Hyung-Chul Park Jong-Sun Kim Sung-Bum Cho Wan-Sik Lee Sung-Kyu Choi Young-Eun Joo 《World Journal of Gastroenterology》 SCIE CAS 2013年第34期5759-5762,共4页
Variceal bleeding is the most serious complication of portal hypertension,and it accounts for approximately one fifth to one third of all deaths in liver cirrhosis patients.Currently,endoscopic treatment remains the p... Variceal bleeding is the most serious complication of portal hypertension,and it accounts for approximately one fifth to one third of all deaths in liver cirrhosis patients.Currently,endoscopic treatment remains the predominant method for the prevention and treatment of variceal bleeding.Endoscopic treatments include band ligation and injection sclerotherapy.Injection sclerotherapy with N-butyl-2-cyanoacrylate has been successfully used to treat variceal bleeding.Although injection sclerotherapy with N-butyl-2-cyanoacrylate provides effective treatment for variceal bleeding,injection of N-butyl-2-cyanoacrylate is associated with a variety of complications,including systemic embolization.Herein,we report a case of cerebral and splenic infarctions after the injection of N-butyl-2-cyanoacrylate to treat esophageal variceal bleeding. 展开更多
关键词 CEREBRUM Esophageal VARIX Infarction n-butyl-2-cyanoacrylate Spleen
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