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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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超临界CO_(2)萃取石榴籽油及石榴酸甲酯富集 被引量:1
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作者 任小娜 李兴梅 +1 位作者 吴江超 库尔班江·艾买提 《食品研究与开发》 CAS 2024年第8期85-90,共6页
采用超临界CO_(2)萃取技术从石榴籽中提取石榴籽油,对其脂肪酸和甘三酯组成和含量进行分析;通过单因素和正交优化试验研究尿素包合法富集石榴酸甲酯。超临界CO_(2)萃取技术与有机溶剂萃取相比更有利于获得高石榴酸含量的石榴籽油,石榴... 采用超临界CO_(2)萃取技术从石榴籽中提取石榴籽油,对其脂肪酸和甘三酯组成和含量进行分析;通过单因素和正交优化试验研究尿素包合法富集石榴酸甲酯。超临界CO_(2)萃取技术与有机溶剂萃取相比更有利于获得高石榴酸含量的石榴籽油,石榴籽油中检测出14种甘三酯。尿素包合法富集石榴酸甲酯的最佳工艺为尿素包合温度5℃、包合时间20 h、尿素与脂肪酸甲酯的质量比1∶1、尿素和95%乙醇的质量比1∶5,此最佳包合条件下获得的石榴酸甲酯的含量为78.82%。 展开更多
关键词 石榴籽油 石榴酸甲酯 尿素包合 石榴酸 超临界CO_(2)
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6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯的合成、晶体结构及抗肿瘤活性研究
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作者 毛云虹 赵春深 《人工晶体学报》 CAS 北大核心 2024年第7期1257-1268,共12页
喹喔啉类化合物由于具有显著的生物活性而被广泛应用于医药、化工领域,特别是抗癌药物研发领域。本文通过四步反应法首次合成了6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯,经溶液结晶法获得其单晶体。晶体学分析表明,该化合... 喹喔啉类化合物由于具有显著的生物活性而被广泛应用于医药、化工领域,特别是抗癌药物研发领域。本文通过四步反应法首次合成了6-氟-4-羟基-3-氧代-3,4-二氢喹喔啉-1(2 H)-羧酸叔丁酯,经溶液结晶法获得其单晶体。晶体学分析表明,该化合物属单斜晶系,空间群C2/c,晶胞常数a=1.28663(10)nm,b=2.25249(17)nm,c=1.01564(7)nm,Z=8,ρ_(c)=1.359 g·cm^(-3),R=0.0538,R_(w)=0.1406。在B3LYP/6-311+G(2d,p)模式下使用密度泛函理论(DFT)计算了该化合物的最佳结构,与X射线单晶衍射确定的晶体结构基本一致。抗肿瘤活性研究表明其有良好的抗肿瘤作用。此外,通过DFT计算了分子的静电势和前沿分子轨道。 展开更多
关键词 喹喔啉类化合物 6-氟-4-羟基-3-氧代-3 4-二氢喹喔啉-1(2 H)-羧酸叔丁酯 晶体结构 密度泛函理论 合成 抗肿瘤活性
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山梨坦(2-丙基)庚酯的合成及性能
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作者 成西涛 南蓉 +3 位作者 黄方方 张金峰 郭鹏涛 杨淑玮 《精细石油化工》 CAS 2024年第3期68-72,共5页
将煤制烯烃(MTO)的副产物2-丙基庚醇通过氧化反应制得2-丙基庚酸,再以其和山梨醇为原料,通过一步法合成了山梨坦(2-丙基)庚酯,采用FT-IR、GC及HPLC进行了表征。结果表明:粗产物中山梨坦(2-丙基)庚酯单酯质量分数可达59.8%,提纯产物中单... 将煤制烯烃(MTO)的副产物2-丙基庚醇通过氧化反应制得2-丙基庚酸,再以其和山梨醇为原料,通过一步法合成了山梨坦(2-丙基)庚酯,采用FT-IR、GC及HPLC进行了表征。结果表明:粗产物中山梨坦(2-丙基)庚酯单酯质量分数可达59.8%,提纯产物中单酯含量可达95.6%。山梨坦(2-丙基)庚酯产品的防腐抑菌性能达到并优于市售山梨坦辛酸酯的水平,具有较好的乳化、助洗功能。将山梨坦(2-丙基)庚酯替代部分表面活性剂加入洗衣液中,无需添加防腐剂,微生物挑战实验7 d,菌落数即小于10 cfu/g,洗涤性能优异。 展开更多
关键词 山梨坦辛酸酯 山梨坦(2-丙基)庚酯 2-丙基庚酸 防腐性能
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气相色谱—串联质谱法测定阿哌沙班中2-氯乙酰乙酸乙酯的残留量
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作者 卢忠秋 王玉如 +3 位作者 刘晓敏 徐淑媛 穆双双 兰公剑 《山东化工》 CAS 2024年第9期136-138,共3页
目的:建立一种气相色谱—串联质谱(GC-MS/MS)方法,用于测定阿哌沙班中潜在基因毒性杂质2-氯乙酰乙酸乙酯的残留量。方法:用聚乙二醇[VF-WAXms(30 mm×0.25 mm×0.25μm)]为固定液的毛细管色谱柱;进样口温度为230℃;流速1.0 mL/m... 目的:建立一种气相色谱—串联质谱(GC-MS/MS)方法,用于测定阿哌沙班中潜在基因毒性杂质2-氯乙酰乙酸乙酯的残留量。方法:用聚乙二醇[VF-WAXms(30 mm×0.25 mm×0.25μm)]为固定液的毛细管色谱柱;进样口温度为230℃;流速1.0 mL/min;载气:氦气;不分流进样。采用电子轰击离子源(EI),选择离子监测模式(SIM)。结果:2-氯乙酰乙酸乙酯在0.05~1.02μg/mL质量浓度范围内呈现良好的线性关系(r=0.9985);定量限浓度是0.02μg/mL;检出限是0.01μg/mL;三份不同浓度水平的平均回收率为97.9%(RSD=4.2%)。结论:所建立的GC-MS/MS测定方法灵敏度高、专属性强和准确度好,可用于阿哌沙班中2-氯乙酰乙酸乙酯的测定。 展开更多
关键词 阿哌沙班 基因毒性杂质 2-氯乙酰乙酸乙酯 气相色谱—串联质谱
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Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium 被引量:9
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作者 黄小卫 李建宁 +3 位作者 龙志奇 张永奇 薛向欣 朱兆武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期410-413,共4页
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a... The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined. 展开更多
关键词 di-(2-ethylhexyl) phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism Sm^3+ Nd^3+ rare earths
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Azalomycin F_(4a) 2-ethylpentyl ester,a new macrocyclic lactone,from mangrove actinomycete Streptomyces sp.211726 被引量:6
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作者 Gan Jun Yuan Kui Hong +1 位作者 Hai Peng Lin Jia Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期947-950,共4页
Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The co... Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116. 展开更多
关键词 Streptomyces sp.211726 Azalomycin F4a 2-ethylpentyl ester Antifungal activity CYTOTOXITY
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Short communication Catalytic synthesis of butyric esters with TiSiW_(12)O_(40)/TiO_2 被引量:46
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作者 YANGShuijin CHENLuchun SUNJutang 《Rare Metals》 SCIE EI CAS CSCD 2003年第1期75-77,共3页
The catalytic activities of TiSiW_(12)O_(40)/TiO_2 in synthesizing ethylester; propyl ester, n-butyl ester; and amyl ester were reported. It was demonstrated thatTiSiW_(12)O_(40)/TiO_2 is an excellent catalyst. Variou... The catalytic activities of TiSiW_(12)O_(40)/TiO_2 in synthesizing ethylester; propyl ester, n-butyl ester; and amyl ester were reported. It was demonstrated thatTiSiW_(12)O_(40)/TiO_2 is an excellent catalyst. Various factors concerned with esterification wereinvestigated. The optimum conditions were found: the mole ratio of alcohol to acid is 1.3:1, themass ratio of catalyst to reactants is 1.5 percent, and the reaction time is 1.0 h. Under theoptimum conditions, the yields are 88.0 percent for ethyl ester, 94.5 percent for propyl ester, 98.6percent for n-butyl ester, 99.1 percent for n-amyl ester, and 96.7 percent for iso-amyl ester,respectively. 展开更多
关键词 butyric ester TiSiW_(12)O_(40)/TiO_2 esterIFICATION CATALYST
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Caffeic acid phenethyl ester up-regulates antioxidant levels in hepatic stellate cell line T6 via an Nrf2-mediated mitogen activated protein kinases pathway 被引量:12
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作者 Ning Yang Juan-Juan Shi +6 位作者 Feng-Ping Wu Mei Li Xin Zhang Ya-Ping Li Song Zhai Xiao-Li Jia Shuang-Suo Dang 《World Journal of Gastroenterology》 SCIE CAS 2017年第7期1203-1214,共12页
AIM To investigate the antioxidant effect of caffeic acid phenethyl ester (CAPE) in hepatic stellate cell-T6 (HSC-T6) cells cultured in vitro and the potential mechanisms. METHODS HSC-T6 cells were cultured in vitro a... AIM To investigate the antioxidant effect of caffeic acid phenethyl ester (CAPE) in hepatic stellate cell-T6 (HSC-T6) cells cultured in vitro and the potential mechanisms. METHODS HSC-T6 cells were cultured in vitro and treated with various concentrations of CAPE for 24, 48 and 72 h, respectively. Cell proliferation was investigated using the MTT assay, and cell ultrastructural alterations were observed by transmission electron microscopy. Flow cytometry was employed to investigate the effects of CAPE on apoptosis and the levels of reactive oxygen species in HSC-T6 cells cultured in vitro. An enzyme immunoassay instrument was used to evaluate antioxidant enzyme expression. The effect on alpha-smooth muscle actin was shown using immunofluorescence. Gene and protein levels of Nrf2, related factors, and mitogen activated protein kinases (MAPKs), in HSC-T6 cells were detected using RT-PCR and Western blot, respectively. RESULTS CAPE inhibited the proliferation and activation of HSC-T6 cells cultured in vitro. CAPE increased the antioxidant levels and the translocation of Nrf2 from the cytoplasm to the nucleus in HSC-T6 cells. Moreover, the phosphorylation of MAPKs in cells decreased in response to CAPE. Interestingly, CAPE-induced oxidative stress in the cells was significantly attenuated by pretreatment with MAPKs inhibitors. CONCLUSION CAPE inhibits cell proliferation and up-regulates the antioxidant levels in HSC-T6 cells partly through the Nrf2-MAPKs signaling pathway. 展开更多
关键词 Caffeic acid phenethyl ester Liver fibrosis ANTIOXIDATION Nrf2 Mitogen activated protein kinases
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奥美沙坦酯联合骨化三醇治疗对早期2型糖尿病肾病患者炎症状态及肾间质纤维化的影响 被引量:6
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作者 魏莉娟 郭姣姣 +1 位作者 何双红 王静 《临床和实验医学杂志》 2023年第4期364-367,共4页
目的研究奥美沙坦酯联合骨化三醇治疗对早期2型糖尿病肾病(T2DN)患者炎症状态及肾间质纤维化的影响。方法以回顾性分析为法,观察对象为2020年1月至2022年1月入四川大学华西医院的100例早期T2DN患者,根据不同治疗方法分为研究组(n=50)与... 目的研究奥美沙坦酯联合骨化三醇治疗对早期2型糖尿病肾病(T2DN)患者炎症状态及肾间质纤维化的影响。方法以回顾性分析为法,观察对象为2020年1月至2022年1月入四川大学华西医院的100例早期T2DN患者,根据不同治疗方法分为研究组(n=50)与对照组(n=50)。研究组联用奥美沙坦酯、骨化三醇治疗,对照组单用奥美沙坦酯治疗,持续用药8周。比较两组患者治疗前后炎症指标[C反应蛋白(CRP)、降钙素原(PCT)]、肾间质纤维化指标[血清同型半胱氨酸(Hcy)、血管内皮生长因子(VEGF)、转化生长因子β1(TGF-β1)]、血糖指标[糖化血红蛋白(HbA1c)、餐后2 h血糖(2 hPG)、空腹血糖]水平、肾功能指标[肾小球滤过率(GFR)、血尿素、血肌酐]水平与治疗后总有效率、不良反应(恶心呕吐、头晕头痛、发热、胃肠道反应)发生率。结果治疗8周后,两组患者的CRP、PCT、Hcy、VEGF、TGF-β1、HbA1c、2 hPG、空腹血糖、血尿素、血肌酐水平较治疗前明显下降,GFR较治疗前明显升高,差异均有统计学意义(P<0.05);研究组患者的CRP、PCT、Hcy、VEGF、TGF-β1、HbA1c、2 hPG、空腹血糖、血尿素、血肌酐水平为(14.36±2.04)mg/L、(1.21±0.08)μg/L、(13.79±1.72)μmol/L、(346.91±23.82)pg/mL、(152.97±18.92)pg/mL、(5.81±0.65)%、(8.36±1.24)mmol/L、(6.18±1.06)mmol/L、(4.27±1.08)mmol/L、(71.28±11.15)μmol/L,较对照组[(16.32±2.26)mg/L、(1.44±0.11)μg/L、(19.34±2.48)μmol/L、(394.36±25.11)pg/mL、(169.04±19.75)pg/mL、(6.42±0.76)%、(10.28±1.39)mmol/L、(7.81±1.12)mmol/L、(5.61±1.16)mmol/L、(78.41±12.37)μmol/L]更低,GFR为(93.85±8.62)mL·min^(-1)·1.73 m^(-2),较对照组[(86.29±8.93)mL·min^(-1)·1.73 m^(-2)]更高,差异均有统计学意义(P<0.05)。研究组患者的治疗总有效率为98.00%,明显高于对照组(84.00%),差异有统计学意义(P<0.05)。两组患者恶心呕吐、头晕头痛、发热、胃肠道反应发生率比较,差异无统计学意义(P>0.05)。结论奥美沙坦酯联合骨化三醇治疗早期T2DN患者的效果显著,可抑制患者炎症反应及肾脏纤维化,改善血糖及肾功能,且无明显副作用,安全性高。 展开更多
关键词 2型糖尿病肾病 奥美沙坦酯 骨化三醇 炎症状态 肾间质纤维化
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Solvent extraction equilibrium of dysprosium(Ⅲ) from nitric acid solutions with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester 被引量:1
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作者 HUANG Ying TANAKA Mikiya 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期707-711,共5页
In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present stu... In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present study,the equilibrium distribution of dysprosium(Ⅲ)between an aqueous nitric acid solution and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A)was measured in the range of an initial aqueous dysprosium(Ⅲ)concentration from 1.0×10-3to 1.0×10-1kmol/m 3and PC88A concentration from 0.16 to 0.65 kmol/m3in Shellsol D70 as the diluent.The obtained data were analyzed using the chemically based model in order to correlate the equilibrium distribution ratios.In this model,dysprosium(Ⅲ)was assumed to be extracted with the PC88A dimer as a 1:3 complex,the activities were considered for the aqueous species,and the effective concentration of the PC88A dimer was calculated using Alstad's empirical equation.As a result,the apparent extraction equilibrium constant was determined to be 253(kmol·m- 3)-2with an excellent correlation between the experiment and calculation results in the wide range of the logarithm of the distribution ratio from-2 to 3.5.In conclusion,the methodology in this model would be effective for quantitative description of solvent extraction behavior of general rare earth elements as well as dysprosium. 展开更多
关键词 solvent extraction DYSPROSIUM 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester(PC88A) nitric acid EQUILIBRIUM
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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
In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate(DHP) and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.... In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate(DHP) and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products. 展开更多
关键词 DEHALOGENATION α-Halo ketones Hantzsch ester 1 4-Dihydro-2 6-dimethylpyridine-3 5-dicarboxylate Potassium iodide
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Revealing the roles of components in glucose selective hydrogenation into 1,2-propanediol and ethylene glycol over Ni-MnO_x-ZnO catalysts 被引量:1
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作者 Yifan Zan Gai Miao +3 位作者 Hao Wang Lingzhao Kong Yaping Ding Yuhan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期15-19,共5页
MnOx-promoted Ni-based catalyst supported by ZnO was developed to selectively hydrogenate glucose into polyols in water at 523 K with a yield of 64.9%. Using glucose, sorbitol, glycerol and LA as the rawmaterials, the... MnOx-promoted Ni-based catalyst supported by ZnO was developed to selectively hydrogenate glucose into polyols in water at 523 K with a yield of 64.9%. Using glucose, sorbitol, glycerol and LA as the rawmaterials, the roles of nickel, ZnO and MnOx were investigated. The results show that nickel provided a new pathway of glucose to sorbitol and played an important role in the hydrogenation of C3 intermediates to 1,2-propanediol(1,2-PDO). The high yield of 1, 2-PDO was attributed to effective C–C bond cleavage performance of ZnO support promoted by MnOx. ZnO and MnOx contribute to the conversion of glycerol to lactic acid(LA) and LA to 1, 2-PDO, respectively. A concise pathway for hydrogenation of glucose over Ni-based catalyst was proposed. 展开更多
关键词 GLUCOSE Hydrogenation 1 2-propanediol Ethylene GLYCOL NI-BASED catalyst
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Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline 被引量:1
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作者 张倩 乌东北 包伯荣 《Journal of Shanghai University(English Edition)》 CAS 2009年第1期72-75,共4页
The synergistic extraction of Pr^3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect o... The synergistic extraction of Pr^3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono- 2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr^3+ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration oil extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr^3+. 展开更多
关键词 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester 8-Hydroxyquinoline (HQ) synergistic extraction praseodymium
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Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation 被引量:1
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作者 薛思佳 申杰峰 +1 位作者 蔡志娟 王庆东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第7期827-831,共5页
The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the in... The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells (chronic myeloid leukemic cells) was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data: C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = -0.15(12), a = 5.7916(10), b = 11.5078(19), c = 12.924(2) A, β = 97.781(3)°, Z = 2, V = 853.4(2) A^3, De = 1.321 g/cm^3, F(000) = 356, -7≤h≤7, -10≤k≤14, -15 ≤ l≤15, R = 0.0628, wR = 0.1540 and μ(MoKa) = 0.327 mm^-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N(1)-H(1A)…O(1) makes a five-membered ring of O(1)--C(6)-C(5)--N(1)--H(1A). 展开更多
关键词 crystal structure N-2-thiophenesulfonyl-α-L-phenylalanine ethyl ester MTT assay
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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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Catalytic conversion of ethyl lactate to 1,2-propanediol over CuO 被引量:1
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作者 Song Zhang Zhibao Huo +4 位作者 Dezhang Ren Jiang Luo Jun Fu Lu Li Fangming Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期126-131,共6页
An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of... An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of ethyl lactate to 1,2-PDO in water, and CuO was more active and gave the best result. The 1,2-PDO yield of 93.6% was achieved when Zn acted as a reductant. The results indicated that in situ formed hydrogen by the oxidation of Zn in water is more effective than gaseous hydrogen, which failed to produce the 1,2-PDO from ethyl lactate.From a practical point of view, the present method may provide a useful route for the production of 1,2-PDO from ethyl lactate. 展开更多
关键词 Biomass 1 2-propanediol Ethyl lactate CuO Hydrothermal reactions
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骨化三醇治疗早期2型糖尿病肾病的临床效果 被引量:2
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作者 黄程 邵云侠 +1 位作者 吴艳 邢昌赢 《中国医药导报》 CAS 2023年第33期92-95,共4页
目的观察骨化三醇治疗早期2型糖尿病肾病的临床效果。方法选取南京医科大学第一附属医院和安徽省芜湖市第二人民医院2019年8月至2022年5月收治的2型糖尿病肾病患者共90例为研究对象,采用随机数字表法将其分为两组,各45例。对照组在常规... 目的观察骨化三醇治疗早期2型糖尿病肾病的临床效果。方法选取南京医科大学第一附属医院和安徽省芜湖市第二人民医院2019年8月至2022年5月收治的2型糖尿病肾病患者共90例为研究对象,采用随机数字表法将其分为两组,各45例。对照组在常规治疗基础上给予奥美沙坦酯治疗,观察组在对照组基础上给予骨化三醇治疗,两组疗程均为8周。比较两组治疗前后肾功能[血肌酐(Scr)、尿白蛋白与肌酐比值(UACR)、微量蛋白尿(MA)、胱抑素C(CysC)],碱性磷酸酶(ALP),血压[舒张压(DBP)、收缩压(SBP)],血糖[空腹血糖(FBG)、糖化血红蛋白(Hb A1c)],NADPH氧化酶4(NOX4)及两组疗效,不良反应发生率。结果治疗后,两组Scr、UACR、MA、Cys C及对照组ALP较治疗前下降,且观察组Scr、UACR、MA、CysC低于对照组(P<0.05);观察组ALP较治疗前升高,且观察组高于对照组(P<0.05)。治疗后,两组SBP、DBP、FBG、Hb A1c均较治疗前降低(P<0.05),组间比较,差异无统计学意义(P>0.05)。治疗后,两组尿液NOX4较治疗前下降,且观察组低于对照组(P<0.05)。观察组疗效优于对照组(P<0.05)。两组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论骨化三醇治疗早期2型糖尿病肾病患者能显著减轻肾功能损伤,提高疗效。 展开更多
关键词 骨化三醇 奥美沙坦酯 早期2型糖尿病肾病 疗效
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New Method for Reducing 2,6-Pyridinedicarboxylic Acid Diethyl Ester to 2,6-Di(hydroxymethyl)pyridine
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作者 Wu Xinyan He Yongbin +2 位作者 Wu Chengtai Wu Xinyan He Yongbin Wu Chengtai (Department of Chemistry, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期105-106,共2页
Reducing 2, 6-pyridinedicaboxylic acid diethyl ester to 2,6-di(hydroxymethyl)pyridine was carried out by using NaBH4/CaCl2 as reducing agent. It is an improved and efficient method. The yield is up to 91%.
关键词 REDUCE 2 6-pyridinedicarboxylic acid diethyl ester 2 6-di (hydroxymethyl) pyridine
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