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3-羟基丙酸甲酯加氢合成1,3-丙二醇反应中La对Cu/SiO_(2)催化剂的修饰作用
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作者 林丽娜 康金灿 +4 位作者 张传明 李伟杰 李昌鑫 赖恩义 朱红平 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期63-72,共10页
[目的] 3-羟基丙酸酯加氢制备1,3-丙二醇(1,3-PDO)过程中存在β-羟基脱除等副反应,导致1,3-PDO的选择性和收率不高,其中高效催化剂的开发是解决该问题的关键.[方法]采用蒸氨法制备了不同添加量La修饰的20Cu/SiO_(2)催化剂,对其进行催化... [目的] 3-羟基丙酸酯加氢制备1,3-丙二醇(1,3-PDO)过程中存在β-羟基脱除等副反应,导致1,3-PDO的选择性和收率不高,其中高效催化剂的开发是解决该问题的关键.[方法]采用蒸氨法制备了不同添加量La修饰的20Cu/SiO_(2)催化剂,对其进行催化性能评价,并通过H_(2)程序升温还原(H_(2)-TPR)、X射线衍射(XRD)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和N_(2)物理吸附-脱附对其进行表征.[结果] 20Cu-0.50La/SiO_(2)的催化性能最佳,它显著地提高了3-羟基丙酸甲酯(3-HMP)加氢制1,3-PDO的催化活性和稳定性,其中3-HMP转化率为91.8%,1,3-PDO的选择性和收率分别为85.2%和78.2%.这是在高液时空速(LHSV=0.10 h^(-1))的条件下取得的最佳结果.[结论] La的加入与Cu产生了强相互作用,增强了催化剂中Cu的分散性,同时提高了Cu^(+)物种表面浓度,使活性Cu的比表面积增加,从而提高了加氢反应的活性和稳定性. 展开更多
关键词 3-羟基丙酸甲酯 加氢 1 3-丙二醇 蒸氨法 CU催化剂 La助剂
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酸碱改性木质活性炭对棕榈油中3-MCPD酯的吸附脱除效果
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作者 侯杰 纪俊敏 孙尚德 《轻工学报》 CAS 北大核心 2024年第1期48-56,共9页
以精炼棕榈油为研究对象,研究4种碳纳米吸附剂(木质活性炭粉末、椰壳活性炭粉末、煤质活性炭粉末和多壁碳纳米管)对3-氯丙醇(3-MCPD)酯的吸附脱除效果,并对最佳吸附剂进行酸碱改性,探究改性后吸附剂添加量、吸附时间和吸附温度对棕榈油... 以精炼棕榈油为研究对象,研究4种碳纳米吸附剂(木质活性炭粉末、椰壳活性炭粉末、煤质活性炭粉末和多壁碳纳米管)对3-氯丙醇(3-MCPD)酯的吸附脱除效果,并对最佳吸附剂进行酸碱改性,探究改性后吸附剂添加量、吸附时间和吸附温度对棕榈油中3-MCPD酯吸附脱除效果的影响。结果表明:对3-MCPD酯的脱除效果为木质活性炭粉末>多壁碳纳米管>椰壳活性炭粉末>煤质活性炭粉末,整体脱除效果欠佳;经4 mol/L H_(3)PO_(4)改性后的木质活性炭粉末,吸附性能增强,在吸附剂添加量为5.85%、吸附时间为47 min、吸附温度为103℃的最佳吸附条件下,对棕榈油中3-MCPD酯的脱除率可达71.82%。使用H_(3)PO_(4)改性木质活性炭可作为脱除食用油中3-MCPD酯的一个有效方法。 展开更多
关键词 木质活性炭 酸碱改性 棕榈油 3-MCPD酯 吸附脱除
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K_(2)CO_(3)/KOH协同醇解废弃涤纶纺织品及其制备再生DMT的研究
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作者 陈斌杰 朱子旭 +3 位作者 官军 吕维扬 王秀华 姚玉元 《丝绸》 CAS CSCD 北大核心 2024年第5期48-57,共10页
废弃涤纶纺织品囤积量逐年上升,而对废弃涤纶纺织品的综合利用回收率却较低。化学法回收中乙二醇醇解-甲醇酯交换法是一种回收废弃涤纶纺织品的方法,然而乙二醇醇解-甲醇酯交换工艺过程中存在对苯二甲酸双羟基乙酯(BHET)单体产率低、低... 废弃涤纶纺织品囤积量逐年上升,而对废弃涤纶纺织品的综合利用回收率却较低。化学法回收中乙二醇醇解-甲醇酯交换法是一种回收废弃涤纶纺织品的方法,然而乙二醇醇解-甲醇酯交换工艺过程中存在对苯二甲酸双羟基乙酯(BHET)单体产率低、低聚物含量高的问题。文章采用K_(2)CO_(3)/KOH协同醇解废弃涤纶纺织品,并结合响应面法优化了醇解工艺参数,通过甲醇酯交换法制得再生对苯二甲酸二甲酯(DMT),研究了K_(2)CO_(3)/KOH协同醇解对乙二醇醇解-甲醇酯交换产物的影响。结果表明,随着KOH添加量的增加,醇解产物中BHET含量呈现先增加后下降的趋势。当KOH的添加量达到2%时,BHET含量达到最高70.2%。同时,优化后的醇解工艺参数为:反应温度210℃、反应时间120 min、K_(2)CO_(3)质量分数2.0%、KOH质量分数2.4%。此时BHET的收率为73.1%;醇解产物与甲醇酯交换得到再生DMT产率为80.1%,通过减压升华纯化后得到再生DMT含量高于99%以上。 展开更多
关键词 废弃涤纶纺织品 K_(2)CO_(3)/KOH协同醇解 酯交换 减压升华 再生DMT
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雪花状Fe_(2)O_(3)-AgNPs SERS基底在大豆基天然酯绝缘油-糠醛检测中的应用
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作者 张盈 邓保家 +5 位作者 雷宇 王明亮 李淑藩 朱磊 陈伟根 万福 《光散射学报》 北大核心 2024年第1期63-71,共9页
本文通过一步水热合成了雪花状三氧化二铁(α-Fe_(2)O_(3))纳米材料,并通过化学还原法在其表面原位生长银纳米颗粒(AgNPs),并将其作为表面增强拉曼散射基底用于检测大豆基天然酯油中的糠醛浓度。根据扫面电子显微镜(SEM),透射电子显微镜... 本文通过一步水热合成了雪花状三氧化二铁(α-Fe_(2)O_(3))纳米材料,并通过化学还原法在其表面原位生长银纳米颗粒(AgNPs),并将其作为表面增强拉曼散射基底用于检测大豆基天然酯油中的糠醛浓度。根据扫面电子显微镜(SEM),透射电子显微镜(TEM),X射线衍射仪(XRD),电化学工作站以及拉曼光谱仪(Raman)分别进行表征。结果表明,以RhB作为探针分子,最低检测限为10-11 mol/L(M),而且相较于单一AgNPs基底,α-Fe_(2)O_(3)-AgNPs的SERS性能更优异。将α-Fe_(2)O_(3)-AgNPs基底进行功能化处理,使其表面修饰4-ATP分子,并用于检测大豆基天然酯绝缘油中的糠醛,最低检测限能达到0.05 mg/L。检测结果完全满足电力行业绝缘油的老化标准(重度老化,4mg/L;中度老化,0.5 mg/L;轻度老化,0.1 mg/L)。 展开更多
关键词 雪花状Fe_(2)O_(3)-AgNPs SERS 糠醛 大豆基天然酯绝缘油
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银杏酮酯滴丸联合尤瑞克林治疗急性脑梗死的效果及对神经因子、PTX3和miR-199a的影响
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作者 张菲菲 燕斌 《临床医学研究与实践》 2024年第16期100-103,共4页
目的探讨银杏酮酯滴丸联合尤瑞克林治疗急性脑梗死的效果及对神经因子、PTX3和miR-199a的影响。方法选择2019年8月至2022年7月收治的78例急性脑梗死患者为研究对象,根据入院时间不同将其分为对照组与观察组,各39例。两组患者入院后均给... 目的探讨银杏酮酯滴丸联合尤瑞克林治疗急性脑梗死的效果及对神经因子、PTX3和miR-199a的影响。方法选择2019年8月至2022年7月收治的78例急性脑梗死患者为研究对象,根据入院时间不同将其分为对照组与观察组,各39例。两组患者入院后均给予对症治疗,对照组在此基础上给予常规溶栓加尤瑞克林治疗,观察组在对照组基础上加银杏酮酯滴丸治疗。比较两组的治疗效果。结果观察组的治疗总有效率高于对照组(P<0.05)。治疗后,观察组的髓鞘碱性蛋白(MBP)、神经生长因子(GFAP)水平低于对照组,胶质纤维酸性蛋白(NGF)水平高于对照组(P<0.05)。治疗后,观察组的正五聚蛋白3(PTX3)水平低于对照组,miR-199a相对表达量高于对照组(P<0.05)。结论银杏酮酯滴丸联合尤瑞克林治疗急性脑梗死的效果满意,可有效改善患者的神经因子水平,调节PTX3水平及miR-199a相对表达量。 展开更多
关键词 银杏酮酯滴丸 尤瑞克林 急性脑梗死 神经因子 正五聚蛋白3 miR-199a
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采用Fluo-3 AM-ester探针研究桃不同组织的Ca^2+信号分布 被引量:2
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作者 鲁振华 王志强 +3 位作者 彭斌 牛良 崔国朝 刘淑娥 《果树学报》 CAS CSCD 北大核心 2011年第5期915-917,I0001,共4页
钙作为植物最重要的矿质元素之一,在植物生理和生化活动中起重要作用。采用激光扫描共聚焦显微镜,以Fluo-3 AM-ester为荧光探针研究了桃果肉和叶柄组织中Ca2+的分布,结果表明Fluo-3 AM-ester可作为荧光探针对桃不同组织中游离的Ca2+信... 钙作为植物最重要的矿质元素之一,在植物生理和生化活动中起重要作用。采用激光扫描共聚焦显微镜,以Fluo-3 AM-ester为荧光探针研究了桃果肉和叶柄组织中Ca2+的分布,结果表明Fluo-3 AM-ester可作为荧光探针对桃不同组织中游离的Ca2+信号强度和分布特征进行分析。不同的物镜观察(10×和20×)下,Ca2+荧光信号相对强度差异不大;在叶柄中Ca2+荧光信号主要分布于维管束,在果实中多分布于细胞壁;但叶柄中荧光信号分布明显高于果肉组织,这与钙在不同组织中的功能有关。 展开更多
关键词 Ca2+信号 激光扫描共聚焦显微镜 Fluo-3AM-ester
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Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester 被引量:1
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作者 HUANG Jie SONG Ji-Rong REN Ying-Hui XU Kang-Zhen MA Hai-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期168-172,共5页
The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in eth... The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis' Crystallographic data: C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672(3), b = 0.66383(12), c = 1.1617(2) nm, β = 109.275(2)°, V = 1.2136(4) nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F(000) = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042. 展开更多
关键词 4-(4 6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction
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植物油精炼过程中缩水甘油酯和3-氯丙醇酯的形成及脱除研究进展 被引量:2
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作者 刘壮 刘萱 +4 位作者 罗日明 陈东升 杨博 王卫飞 蓝东明 《中国油脂》 CAS CSCD 北大核心 2023年第3期64-70,共7页
缩水甘油酯(GEs)和3-氯丙醇酯(3-MCPDE)是植物油精炼过程中产生的主要污染物之一。GEs和3-MCPDE伴随食用油摄入人体后,经脂肪酶水解产生的缩水甘油和3-氯丙醇具有肾脏毒性和遗传毒性。植物油中GEs和3-MCPDE主要产生于油脂精炼脱臭工段,... 缩水甘油酯(GEs)和3-氯丙醇酯(3-MCPDE)是植物油精炼过程中产生的主要污染物之一。GEs和3-MCPDE伴随食用油摄入人体后,经脂肪酶水解产生的缩水甘油和3-氯丙醇具有肾脏毒性和遗传毒性。植物油中GEs和3-MCPDE主要产生于油脂精炼脱臭工段,脱臭温度、脱臭时间对GEs和3-MCPDE的生成影响巨大。从油脂精炼加工过程中GEs和3-MCPDE的形成及脱除等方面进行了综述,指出脱色和脱臭工段可促进GEs和3-MCPDE的生成,当前可通过抑制及脱除其前体物质、优化植物油脱臭条件、脱除精炼油中的GEs及3-MCPDE等方式降低植物油中GEs和3-MCPDE含量。酶制剂具有安全、无污染等优点,通过酶法酯交换降低待脱臭油脂中的甘油二酯和甘油单酯,进而减少脱臭过程中GEs及3-MCPDE的生成是降低GEs和3-MCPDE的发展趋势。 展开更多
关键词 植物油 缩水甘油酯 3-氯丙醇酯 油脂精炼 脱臭温度
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Crystal Structure and Anticancer Properties of Cinobufagin 3-Hemisuberate Methyl Ester 被引量:1
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作者 张冤 冯娟 +2 位作者 叶文才 田海妍 江仁望 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期790-794,共5页
The title compound cinobufagin 3-hemisuberate methyl ester(1) was isolated from the venom of Bufo bufo gargarizans CANTOR. The crystal structure of 1, C35H48O9, was determined by single-crystal X-ray diffraction ana... The title compound cinobufagin 3-hemisuberate methyl ester(1) was isolated from the venom of Bufo bufo gargarizans CANTOR. The crystal structure of 1, C35H48O9, was determined by single-crystal X-ray diffraction analysis. It belongs to orthorhombic, space group P212121 with a = 8.9338(3), b = 16.2970(4), c = 22.4019(6) , V = 3261.59(16) 3, Mr = 612.73, Z = 4, Dc = 1.248 g/cm3, μ = 0.725 mm-1, F(000) = 1320, S = 1.040, the final R = 0.0374 and wR = 0.0412 for 4458 unique reflections, of which 4088 were observed(I 〉 2σ(I)). In the solid state, short intermolecular C-H...O interactions involving a methine and the ester carbonyl group in cinobufagin moiety and a methyl in the suberate moiety linked adjacent molecules into a three-dimensional network. Detailed analysis of the 1H-NMR data showed that X-ray structure of 1 would be expected to closely resemble the solution conformation in chloroform. Compound 1 was inactive for the inhibition of PC3 and HepG2 cancer cells, but the parent compound cinobufagin showed potent inhibition with IC50 values of 0.145 and 5.48 μM, respectively, indicating that esterification at C(3) decreased the cytotoxic effect of 1. 展开更多
关键词 crystal structure cinobufagin 3-hemisuberate methyl ester anticancer
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Potassium iodide catalyzed reductive dehalogenation ofα-halo-ketones using Hantzsch ester diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate as reductant 被引量:1
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作者 Hong Sheng Li Yi Qun Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期931-934,共4页
面对 diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (DHP ) 和钾碘化物的催化数量,几个伪 - 光圈酉同类容易在丙酮媒介被归结为相应酉同类。这里介绍的过程显示出象产品的短反应时间,实际试验性、孤立的过程,和优秀... 面对 diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (DHP ) 和钾碘化物的催化数量,几个伪 - 光圈酉同类容易在丙酮媒介被归结为相应酉同类。这里介绍的过程显示出象产品的短反应时间,实际试验性、孤立的过程,和优秀收益那样的几个优点。 展开更多
关键词 二乙基酮 催化还原 碘化钾 二甲基 二羧酸 二乙酯 二氢 还原剂
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气相色谱-串联质谱法测定婴幼儿配方乳粉中的3-氯丙醇酯和缩水甘油酯及其风险评估
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作者 郝宇 马艺荧 +4 位作者 于力涛 李广志 魏志春 刘树萍 石长波 《食品科学》 EI CAS CSCD 北大核心 2023年第8期337-344,共8页
建立检测婴幼儿配方乳粉中3-氯丙醇酯和缩水甘油酯的气相色谱-串联质谱法,测定不同市售婴幼儿配方乳粉中3-氯丙醇酯和缩水甘油酯的含量,掌握婴幼儿配方乳粉中酯类污染情况并进行安全风险评估。采用正己烷提取婴幼儿配方乳粉中的3-氯丙... 建立检测婴幼儿配方乳粉中3-氯丙醇酯和缩水甘油酯的气相色谱-串联质谱法,测定不同市售婴幼儿配方乳粉中3-氯丙醇酯和缩水甘油酯的含量,掌握婴幼儿配方乳粉中酯类污染情况并进行安全风险评估。采用正己烷提取婴幼儿配方乳粉中的3-氯丙醇酯和缩水甘油酯,经过水解、苯基硼酸衍生、气相色谱-串联质谱法测定,内标法定量。结果表明,3-氯丙醇酯和缩水甘油酯总量在0.0400~4.00μg/mL、3-氯丙醇酯含量在0.0200~2.00μg/mL的范围内线性良好,相关系数R2>0.999,检出限均为10.0μg/kg,定量限均为25.0μg/kg。在25.0、100、300μg/kg添加水平下,平均回收率在95.0%~98.1%之间。该方法准确率高、回收率好,可用于婴幼儿配方乳粉中的3-氯丙醇酯和缩水甘油酯的检测。150份市售婴幼儿配方乳粉样品中,3-氯丙醇酯检出率为12.7%,含量为ND~52.4μg/kg,平均检出值为29.8μg/kg。缩水甘油酯检出率为6.67%,含量为ND~40.1μg/kg,平均检出值为31.9μg/kg。3-氯丙醇酯的平均暴露水平为0.33~0.66μg/(kg·d),婴幼儿配方乳粉中3-氯丙醇酯和缩水甘油酯污染问题值得重视。 展开更多
关键词 3-氯丙醇酯 缩水甘油酯 气相色谱-串联质谱法 婴幼儿配方乳粉
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Synthesis and Crystal Structure of 4-(4,6-Dimethoxylpyrimidin-2-yl)-3-thiourea Carboxylic Acid Ethyl Ester
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作者 ZHANG Yang HUANG Jie +2 位作者 SONG Ji-Rong REN Ying-Hui XU Kang-Zhen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期195-199,共5页
4-(4,6-Dimethoxyl-pyrimidin-2-yl)-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single ... 4-(4,6-Dimethoxyl-pyrimidin-2-yl)-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data: C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309(3), b = 0.67682(6), c = 1.74237(19) nm, β = 114.744(3)°, V= 2.7106(5) nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F(000) = 1200, Z= 8, R= 0.0514 and wR= 0.1529. 展开更多
关键词 4-(4 6-dimethoxyl-pyrimidin-2-yl)-3-thiourea carboxylic acid ethyl ester synthesis crystal structure ^-~ aromatic stacking interactions
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A Novel Synthesis of Methyl 4, 6-O-Benzylidene-α-D-Glucopyranoside 2, 3-Cyclic Phosphite Ethyl Ester
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作者 Jian Jun HU Yong JU Yu Fen ZHAO(Bioorganic Phosphorus Chemistry Laboratory, Department of Chemisrty.Tsinghua University. Beijing. 100084) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期457-458,共2页
A new compound. methyl 4. 6-O-benzylidene-a-D-glucopyranoside 2. 3-cyclicphosphite ethyl ester was synthesized via the reaction of methyl 4. 6-O-benzylidene-a-D-glucopyranoside and ethyl dichlorophosphite. Its structu... A new compound. methyl 4. 6-O-benzylidene-a-D-glucopyranoside 2. 3-cyclicphosphite ethyl ester was synthesized via the reaction of methyl 4. 6-O-benzylidene-a-D-glucopyranoside and ethyl dichlorophosphite. Its structure was confirmed by NMR and MSspectral methods. 展开更多
关键词 2. 3-Cyclic glucopyranosyl phosphite ester synthesis structure determination
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 The Synthesis of 9 H 7 H-12-Eudesmanoic Acid Methyl ester Dien-5 Study on the Total Synthesis of 3-Oxo-9 Acetoxyilicic Acid Acetoxy-3
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Aqueous Two Phase Extraction for the Recovery of 1,3-Propanediol from Its Aqueous Solutions
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作者 Min Hee Chung Yeon Ki Hong +1 位作者 Hyoung Wook Lee Sung-Jun Park 《Advances in Materials Physics and Chemistry》 2012年第4期154-157,共4页
As the biodiesel production is rapidly enhanced, the crude glycerol, which is by-product of biodiesel processes, is state of surplus. 1,3-PDO (1,3-propanediol), a valuable monomer of poly(trimethylene terephthalate) (... As the biodiesel production is rapidly enhanced, the crude glycerol, which is by-product of biodiesel processes, is state of surplus. 1,3-PDO (1,3-propanediol), a valuable monomer of poly(trimethylene terephthalate) (PTT), can be produced from the fermentation process using crude glycerin as a carbon source. For the economic biological production of 1,3-PDO, the low cost and high efficient separation processes is essential. In this study, aqueous two-phase system composed of various hydrophilic alcohols and salt was used as a primary separation step for 1,3-PDO. It was found that the aqueous two-phase systems are easily formed with decreasing of the polarity of alcohols. The extraction efficiency is proportional to the polarity of alcohols. In case of methanol or ethanol/K2HPO4, the extraction efficiency was more than 90%.? It was concluded that the aqueous two-phase extraction using methanol or ethanol/K2HPO4 can be applied? for the primary separation of 1,3-PDO? as an alternative to a conventional primary separation processes. 展开更多
关键词 1 3-propanediol ALCOHOLS Phase Separation EXTRACTION Efficiency
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Isolation and Identification of Alkali-Resistant 1,3-Propanediol Producing Strain
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作者 Zhifang Zhao Caifang Wen +3 位作者 Guang Rong Ruiqing Liu Jianguo Xu Qingping Hu 《Advances in Microbiology》 2016年第12期917-926,共11页
1,3-Propanediol is a promising renewable resource produced by microbial production. It is mainly used in many synthetic reactions, particularly applied to the polymer synthesis and cosmetics industry. We described her... 1,3-Propanediol is a promising renewable resource produced by microbial production. It is mainly used in many synthetic reactions, particularly applied to the polymer synthesis and cosmetics industry. We described here the isolation of strain ZH-1, which has the ability of high production with 1,3-propanediol, from Fenhe River in China. It was classified as a member of K. pneumoniae after the study of phenotypic, physio-logical, biochemical and phylogenetic (16S rDNA). The initial glycerol concentration, fermentation time and pH value of strain ZH-1 were determined to be 50 g·L<sup>-1</sup>, 36 h and 8.0. Under these conditions, the practical yield of 1,3-PD was 18.53 g·L<sup>-1</sup> and a molar yield (mol<sub>1,3-PD</sub> mol<sub>Glycerol</sub>-1</sup> of 1,3-propanediol to glycerol of 0.497. In addition, we found that for the strain ZH-1, the optimum grown pH was 9.0, so we can deter-mine that it is a new member of alkali-resistant strains. 展开更多
关键词 1 3-propanediol K. pneumoniae Identification Alkali-Resistant
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市售食用植物油中3-氯丙醇酯污染水平分析
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作者 张涵 卫杨帆 +1 位作者 程胜 王忠凯 《湖北理工学院学报》 2023年第6期56-59,共4页
食用油中脂肪酸氯丙醇酯是近年来国际关注的新食品污染物,其中3-氯-1,2-丙二醇脂肪酸酯(3-MCPDE)的污染问题更为突出。文章采用气相色谱/质谱法研究了2017—2019年从湖北省7个地市采集的105份市售食用植物油中3-MCPDE的污染情况。研究... 食用油中脂肪酸氯丙醇酯是近年来国际关注的新食品污染物,其中3-氯-1,2-丙二醇脂肪酸酯(3-MCPDE)的污染问题更为突出。文章采用气相色谱/质谱法研究了2017—2019年从湖北省7个地市采集的105份市售食用植物油中3-MCPDE的污染情况。研究结果表明:105份食用植物油中3-MCPDE的检出率为92.4%,3-MCPDE的检出范围在ND~3.36 mg/kg,表明湖北省市售食用植物油中普遍存在3-MCPDE的污染,且不同种类的食用植物油中3-MCPDE的污染水平差异性较大,因此有必要加大监测力度。 展开更多
关键词 食用植物油 3-氯丙醇酯 气相色谱/质谱法 风险监测 食品安全
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高n-3多不饱和脂肪酸甘油酯型鱼油的制备工艺
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作者 孙兆敏 黄海华 +4 位作者 刘萌 李颖 阎光宇 倪辉 余蕾 《福建技术师范学院学报》 2023年第2期210-217,共8页
以二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)质量分数分别为25.17%和15.34%的乙酯型鱼油为初始原料,首先通过分子蒸馏技术获得EPA和DHA总质量分数在70%以上的乙酯型鱼油,考察蒸馏温度对鱼油中EPA和DHA质量分数及比值(EPA/DHA值)的影响.... 以二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)质量分数分别为25.17%和15.34%的乙酯型鱼油为初始原料,首先通过分子蒸馏技术获得EPA和DHA总质量分数在70%以上的乙酯型鱼油,考察蒸馏温度对鱼油中EPA和DHA质量分数及比值(EPA/DHA值)的影响.发现当分子蒸馏原料中EPA和DHA总质量分数较低时(如40.51%),分子蒸馏可实现n-3多不饱和脂肪酸的富集;对于EPA和DHA总质量分数高于70%的乙酯型鱼油,分子蒸馏的作用以调节EPA/DHA值为主,且EPA/DHA值与分子蒸馏温度(90~130℃)呈现较好的线性关系.随后,对EPA和DHA总质量分数在70%以上的乙酯型鱼油进行尿素包合处理,发现尿素包合技术可进一步增加高含量乙酯型鱼油中EPA和DHA的质量分数(至80.82%~91.61%),但对EPA/DHA值影响较小.最后通过酶促甘油解方法将联合使用分子蒸馏、尿素包合技术得到的一系列高含量乙酯型鱼油转变为甘油酯型. 展开更多
关键词 乙酯型鱼油 N-3多不饱和脂肪酸 分子蒸馏 尿素包合 甘油解
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Isolation of New Strains of Bacteria Able to Synthesize 1,3-Propanediol from Glycerol
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作者 Daria Szymanowska-Powalowska Agnieszka Drozdzyńska Natalia Remszel 《Advances in Microbiology》 2013年第2期171-180,共10页
The natural environment is inhabited by many species that exhibit very specific metabolic activities that may find industrial applications. The aim of the study was to select non-pathogenic cultures of bacteria of the... The natural environment is inhabited by many species that exhibit very specific metabolic activities that may find industrial applications. The aim of the study was to select non-pathogenic cultures of bacteria of the genus Clostridium and lactic acid bacteria able to convert glycerol into 1,3-propanediol (1,3-PD). Another aim of this study was to identify the isolates that best produced 1,3-propanediol both from pure and crude glycerol. The most efficient strains identified (Cl. butyricum) were analysed on a bioreactor scale. The aim was to determine temperature conditions on the efficiency and duration of 1,3-PD synthesis. The species Clostridium were identified using amplification of the 16S rRNA coding sequence. A total of 123 isolates (of the genus Clostridium and lactic acid bacteria) were isolated;a vast majority of these were able to synthesize 1,3-PD. The best results were obtained for Cl. butyricum strain DSP1, which was isolated from the rumen of a cow fed with glycerol. The strain efficiency using pure glycerol on bioreactor scale 0.65 mol/mol of glycerol at a temperature of 38℃ and a constant pH of 7.0. 展开更多
关键词 Clostridium spp. Bacteria Isolation 1 3-propanediol Glycerol Conversion Microflora of Natural Environment
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Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester
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作者 WEI Hui-Qin ZENG Run-Sheng WU Gui-Ping WANG Bao-An ZOU Jian-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期1014-1018,共5页
The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin- 2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester 8 (C28H28N2O10, Mr = 552.54), has been synthesized and its crystal structure was determined ... The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin- 2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester 8 (C28H28N2O10, Mr = 552.54), has been synthesized and its crystal structure was determined by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21, a = 10.060(8), b = 5.648(4), c = 24.11(2)A, β = 91.078(10)°, Z = 2, V= 1369.9(19)A^3, Dc = 1.339 g/cm^3,μ(MoKa) = 1.03 cm^-1, F(000) = 580.00, T =. 193.1 Kx-9 θmax = 25.03, (△/σ)max = 0.0000, Flack = -0.0(24), the final R = 0.0680 and wR = 0.140 (w = 1/[0.0016Fo^2 + 1.00000(Fo^2)]/(4Fo^2)) for 3126 observed reflections (1 〉 20(/)). The pyranoid ring adopts chair conformation in the sugar moiety, and all of the acetyl groups are in the e bond of the pyranoid ring, so the sugar moiety is very stable. 展开更多
关键词 acetic acid-3 5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester synthesis crystal structure
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