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电容器用双向拉伸聚4-甲基-1-戊烯(BOPMP)薄膜开发与应用
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作者 储松潮 潘毓娴 +5 位作者 黄云锴 潘焱尧 石兆峰 汪威 唐兵 冯玲 《电力电容器与无功补偿》 2024年第1期41-48,共8页
聚4-甲基-1-戊烯(PMP)是一种具有等规结构的新型热塑性塑料,PMP为结晶性树脂,熔点在235℃~240℃之间,耐热性好,可在高温下使用,并具有卓越的电气绝缘和介电性能。与聚丙烯树脂相比,熔点高60℃,介电常数、介电损耗相近。随着我国电子工... 聚4-甲基-1-戊烯(PMP)是一种具有等规结构的新型热塑性塑料,PMP为结晶性树脂,熔点在235℃~240℃之间,耐热性好,可在高温下使用,并具有卓越的电气绝缘和介电性能。与聚丙烯树脂相比,熔点高60℃,介电常数、介电损耗相近。随着我国电子工业的发展,PMP的用量在近年来有大幅的增长。目前世界上只有日本三井化学株式会社生产,由于产量有限、售价较高,限制了PMP在国内的应用。为此本文尝试采用双向拉伸的方法,试制聚4-甲基-1-戊烯(BOPMP)薄膜,并加工成金属化膜,试制电容器,最后对电容器的性能进行相应测试评价。采用不同牌号原料生产BOPMP薄膜,其电压击穿强度差别较大,不同频率下的BOPMP薄膜电容器损耗角正切值、介电常数均与BOPP薄膜电容器接近,但其高温下的性能有待进一步验证。如何提升BOPMP薄膜电压击穿强度及其耐热性,开发出适宜于双向拉伸的PMP粒子原料,生产出高质量的BOPMP电容薄膜,将是未来重点研究的方向。 展开更多
关键词 金属化薄膜电容器 4-甲基1-戊烯 双向拉伸 BOPMP
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佛手多糖对1-甲基-4-苯基-吡啶离子诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用研究
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作者 陈进炫 龚舒 +3 位作者 刘天开 龚记熠 乙引 刘文华 《食品与发酵工业》 CAS CSCD 北大核心 2024年第8期17-23,共7页
该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s dis... 该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s disease,PD)细胞模型,实验分为对照组、MPP+模型组、佛手多糖组。采用噻唑蓝(methye thiazdye telrazlium,MTT)法检测细胞存活率,Hoechst33258染色法观察细胞形态,2′,7′-二氯荧光黄双乙酸盐荧光探针检测细胞活性氧(reactive oxygen species,ROS)水平,JC-1荧光探针法检测线粒体膜电位,蛋白免疫印迹(Western blot)检测磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、蛋白激酶B(protein kinase B,Akt)、磷酸化细胞外调节蛋白激酶(phosphorylated extracellular regulated protein kinases1/2,p-ERK1/2)和细胞色素c(cytochrome c,Cyt-c)蛋白表达水平。结果表明,佛手多糖的得率4.86%,纯度为44.46%,经过AB-8纯化后,纯度提高到60.81%;与对照组相比,模型组细胞的存活率显著降低,Hoechst33258染色下可见细胞破碎,细胞核皱缩,细胞内ROS显著增加,线粒体膜电位显著降低。与模型组相比,佛手多糖组的细胞存活率显著增加,细胞形态明显得到改善,ROS水平下降,线粒体膜电位升高。Western blot结果显示,佛手多糖能抑制MPP+引起的p-Akt和p-ERK1/2的降低,以及Cyt-c的上升。综上,佛手多糖对MPP+诱导SH-SY5Y细胞损伤具有保护作用,其机制可能是通过调节线粒体ROS的产生和Cyt-c的释放,进而维持线粒体稳态,激活Akt信号通路和ERK信号通路,抑制细胞的凋亡,从而起到保护作用。研究结果可为缓解帕金森病的发生发展提供理论依据,同时也能更好地开发和利用佛手资源。 展开更多
关键词 佛手多糖 提取纯化 MPP+ SH-SY5Y细胞 保护作用
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3-甲基-1-戊烯-4-炔-3-醇合成工艺的改进
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作者 赵嘉伟 翟德伟 +3 位作者 刘冬 王伟江 胡立 张益林 《工业催化》 CAS 2024年第5期70-74,共5页
以液氨和金属钙为原料通过氨基化制得氨基钙,经炔化得到乙炔钙,乙炔钙再与甲基乙烯酮反应制得乙炔醇钙盐,经水解、挥发氨、水蒸气蒸馏、萃取、回收溶剂、粗馏、精馏制得3-甲基-1-戊烯-4-炔-3-醇。考察金属试剂、催化剂硝酸高铁投入量、... 以液氨和金属钙为原料通过氨基化制得氨基钙,经炔化得到乙炔钙,乙炔钙再与甲基乙烯酮反应制得乙炔醇钙盐,经水解、挥发氨、水蒸气蒸馏、萃取、回收溶剂、粗馏、精馏制得3-甲基-1-戊烯-4-炔-3-醇。考察金属试剂、催化剂硝酸高铁投入量、阻聚剂和萃取剂对合成及产物的影响。结果表明,选用金属钙作为金属试剂,催化剂硝酸高铁投入量为金属钙质量的0.8%,改性复合阻聚剂和CH2Cl2萃取剂较为合适。该工艺合成路线得到的3-甲基-1-戊烯-4-炔-3-醇纯度达98%以上,物质的量收率71.0%。 展开更多
关键词 精细化学工程 氨基化 甲基乙烯酮 阻聚剂 3-甲基-1-戊烯-4-炔-3-醇
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一种合成4-亚苄基-3-甲基-1-苯基吡唑啉酮的新方法
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作者 赵林权 刘敏 +2 位作者 杨艳春 刘璐 宋祥家 《化工技术与开发》 CAS 2024年第6期15-17,40,共4页
4-亚苄基-3-甲基-1-苯基吡唑啉酮是一种重要的合成子,合成4-亚苄基-3-甲基-1-苯基吡唑啉酮的方法较多,但反应条件较为苛刻。本文用苯并噻唑亚胺与吡唑酮进行反应,合成了4-亚苄基-3-甲基-1-苯基吡唑啉酮,收率高达96%,并进行了普适性研究... 4-亚苄基-3-甲基-1-苯基吡唑啉酮是一种重要的合成子,合成4-亚苄基-3-甲基-1-苯基吡唑啉酮的方法较多,但反应条件较为苛刻。本文用苯并噻唑亚胺与吡唑酮进行反应,合成了4-亚苄基-3-甲基-1-苯基吡唑啉酮,收率高达96%,并进行了普适性研究,均能以较好的收率得到目标产物。 展开更多
关键词 4-亚苄基-3-甲基-1-苯基吡唑啉酮 苯并噻唑亚胺 吡唑酮
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Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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作者 Emeline Sorelle Mefouegang Claudelle Sybilline Anensong Djadock +5 位作者 Golngar Djimassingar Gabriel Tchuente Kamsu Donald Raoul Tchuifon Tchuifon Alain Charly Tagne Kuate Dirk Bockfeld Jean Ngoune 《Journal of Materials Science and Chemical Engineering》 2023年第8期109-126,共18页
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s... New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus). 展开更多
关键词 COBALT ACYLPYRAZOLONE X-Ray Diffraction Antimicrobial Activity 3-methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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Synthesis, Structural Characterization and Antimicrobial Activity of a Novel Cobalt(II) Complex Based on 3-Methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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作者 Emeline Sorelle Mefouegang Claudelle Sybilline Anensong Djadock +5 位作者 Golngar Djimassingar Gabriel Tchuente Kamsu Donald Raoul Tchuifon Tchuifon Alain Charly Tagne Kuate Dirk Bockfeld Jean Ngoune 《Journal of Modern Physics》 2023年第8期109-126,共12页
New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<s... New cobalt(II) complex, [Co(O<sub>2</sub>C<sub>15</sub>H<sub>11</sub>N<sub>2</sub>S)<sub>2</sub>(OH<sub>2</sub>)<sub>2</sub>]∙2H<sub>2</sub>O (1∙2H<sub>2</sub>O), has been synthesized upon reaction of cobalt chloride hexahydrate (Co(Cl)<sub>2</sub>∙6H<sub>2</sub>O) with 3-methyl-1-Phenyl-4-(2-thienoyl)-pyrazol-5-one (referred as HL) in ethanol at room temperature. Single crystal X-ray diffraction (XRD), spectroscopic methods, and microelemental analyses were used to characterize 1∙2H<sub>2</sub>O. Compound 1∙2H<sub>2</sub>O crystallizes in the orthorhombic crystal system with a Pbca space group and with the cobalt atom being pseudo-octahedral coordinated. The broth microdilution technique was used to screen the free ligand (HL) and the complex (1∙2H<sub>2</sub>O) for antimicrobial activities. HL has a low activity (MIC > 100 μg/mL) on all microorganisms, whereas compound 1∙2H<sub>2</sub>O displayed moderate activity (10 ∙2H<sub>2</sub>O exhibited bactericidal and fungicidal activity respectively on all the bacteria and yeasts tested. These findings reveal that the antimicrobial activity of HL was enhanced upon coordination to Co(II) ion against all microorganisms (bacteria and fungus). 展开更多
关键词 COBALT ACYLPYRAZOLONE X-Ray Diffraction Antimicrobial Activity 3-methyl-1-Phenyl-4-(2-Thienoyl)-Pyrazol-5-One
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乌梅总黄酮调控miR-145-3p表达对MPP+诱导SH-SY5Y细胞损伤的作用及其机制
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作者 文晓东 王春玲 +3 位作者 蒋媛静 周欣梅 张艺 伍媛 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2023年第6期1415-1423,共9页
目的:探讨乌梅总黄酮(FMF)调控微小RNA (miR)-145-3p对多巴胺能毒素1-甲基-4-苯基吡啶(MPP+)诱导的SH-SY5Y细胞损伤的保护作用,并阐明其作用机制。方法:构建MPP+诱导帕金森病(PD) SH-SY5Y细胞模型,CCK-8法筛选MPP+和FMF最佳干预浓度和... 目的:探讨乌梅总黄酮(FMF)调控微小RNA (miR)-145-3p对多巴胺能毒素1-甲基-4-苯基吡啶(MPP+)诱导的SH-SY5Y细胞损伤的保护作用,并阐明其作用机制。方法:构建MPP+诱导帕金森病(PD) SH-SY5Y细胞模型,CCK-8法筛选MPP+和FMF最佳干预浓度和作用时间。将细胞分为对照组(未经处理)、模型组(500μmol·L^(-1)MPP+作用24 h)、MPP++mimics组(转染miR-145-3p mimics)、MPP++NC组(转染miR-145-3p NC)、MPP++FMF组(0.25 g·L^(-1)FMF作用24h)、 MPP++mimics+FMF组(转染miR-145-3pmimics后0.25g·L^(-1)FMF作用24h)和MPP++NC+FMF组(转染miR-145-3p NC后0.25 g·L-1FMF作用24 h)。CCK-8法检测各组细胞增殖能力,AnnexinⅤ-FITC/PI染色法检测各组细胞凋亡率,透射电镜观察各组细胞线粒体自噬超微结构表现,实时荧光定量PCR (RT-qPCR)法检测各组细胞中miR-145-3p表达水平,Western blotting法检测各组细胞中Beclin-1蛋白表达水平和LC3-Ⅱ/LC3-Ⅰ比值。结果:不同浓度MPP+作用SH-SY5Y细胞后,细胞增殖能力明显降低(P<0.01),PD细胞模型构建成功。MPP+最佳作用浓度和时间为500μmol·L^(-1)和24 h,FMF最佳干预浓度和作用时间为0.25 g·L^(-1)和24 h。CCK-8法检测,与对照组比较,模型组细胞增殖能力明显降低(P<0.01);与模型组比较,MPP++mimics组和MPP++FMF组细胞增殖能力均明显升高(P<0.01);与MPP++FMF组比较,MPP++mimics+FMF组细胞增殖能力明显升高(P<0.01)。AnnexinⅤ-FITC/PI染色法检测,与对照组比较,模型组细胞凋亡率明显升高(P<0.01);与模型组比较,MPP++mimics组和MPP++FMF组细胞凋亡率均明显降低(P<0.01);与MPP++FMF组比较,MPP++mimics+FMF组细胞凋亡率明显降低(P<0.01)。透射电镜观察,对照组细胞线粒体形态均匀,结构完整;模型组细胞线粒体体积变大,结构不规则,出现空化现象;与模型组比较,MPP++mimics组和MPP++FMF组细胞线粒体结构改善,自噬小体数量增加;与MPP++FMF组比较,MPP++mimics+FMF组细胞线粒体结构较为完整,自噬小体数量进一步增加。RT-qPCR法检测,与对照组比较,模型组细胞中miR-145-3p表达水平明显降低(P<0.01);与模型组比较,MPP++mimics组和MPP++FMF组细胞中miR-145-3p表达水平均明显升高(P<0.01);与MPP++FMF组比较,MPP++mimics+FMF组细胞中miR-145-3p表达水平明显升高(P<0.01)。Western blotting法检测,与对照组比较,模型组细胞中Beclin-1蛋白表达水平和LC3-Ⅱ/LC3-Ⅰ比值均降低(P<0.05);与模型组比较,MPP++mimics组和MPP++FMF组细胞中Beclin-1蛋白表达水平和LC3-Ⅱ/LC3-Ⅰ比值均明显升高(P<0.01);与MPP++FMF组比较,MPP++mimics+FMF组细胞中Beclin-1蛋白表达水平和LC3-Ⅱ/LC3-Ⅰ比值均明显升高(P<0.01)。结论:FMF能够促进MPP+诱导的SH-SY5Y细胞自噬作用,减轻线粒体功能障碍,缓解MPP+诱导的SH-SY5Y细胞损伤,其作用机制与上调miR-145-3p表达有关。 展开更多
关键词 乌梅总黄酮 微小RNA-145-3p 多巴胺能毒素1-甲基-4-苯基吡啶 帕金森病 线粒体自噬
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聚4-甲基-1-戊烯的合成、结构与应用研究进展 被引量:1
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作者 张垚 唐毓婧 +4 位作者 郭子芳 贾雪飞 王伟 李昊坤 姜志勇 《合成树脂及塑料》 CAS 北大核心 2023年第3期62-67,86,共7页
从聚4-甲基-1-戊烯(PMP)的单体、催化剂、合成、分子链结构、晶体结构以及结晶行为进行阐述,综述了其在电子电器、节能降耗、包装材料以及医疗器械等领域的最新应用。PMP的合成包括丙烯二聚合成单体4-甲基-1-戊烯及其聚合。PMP合成技术... 从聚4-甲基-1-戊烯(PMP)的单体、催化剂、合成、分子链结构、晶体结构以及结晶行为进行阐述,综述了其在电子电器、节能降耗、包装材料以及医疗器械等领域的最新应用。PMP的合成包括丙烯二聚合成单体4-甲基-1-戊烯及其聚合。PMP合成技术有两种:一种是采用Ziegler-Natta催化剂的配位聚合,使用的主催化剂为TiX(X表示卤素原子),助催化剂为烷基铝;第二种是阳离子聚合。最后对PMP性能优化以及国产化提出展望。 展开更多
关键词 4-甲基-1-戊烯 合成 结晶行为
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1⁃苯基⁃3⁃甲基⁃4⁃苯甲酰基⁃5⁃吡唑啉酮稀土配合物的合成、晶体结构、发光性能与密度泛函理论计算 被引量:1
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作者 龙忠学 李巍 +2 位作者 李东芳 景佳慧 刘姗姗 《无机化学学报》 SCIE CAS CSCD 北大核心 2023年第3期385-394,共10页
以1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮(Hpmbp)和4,4′-二甲基-2,2′-联吡啶(dmbipy)为配体合成了一类单核稀土配合物[Ln(pmbp)3(dmbipy)]·C2H_(5)OH,其中Ln=Tb(1⁃Tb)、Ho(1⁃Ho)、Er(1⁃Er)、Tm(1⁃Tm)。结构表征显示该类配合物由... 以1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮(Hpmbp)和4,4′-二甲基-2,2′-联吡啶(dmbipy)为配体合成了一类单核稀土配合物[Ln(pmbp)3(dmbipy)]·C2H_(5)OH,其中Ln=Tb(1⁃Tb)、Ho(1⁃Ho)、Er(1⁃Er)、Tm(1⁃Tm)。结构表征显示该类配合物由稀土金属离子与3个pmbp-配体、1个dmbipy配体配位而成,同时存在一分子非配位的乙醇。Ln^(3+)离子的配位环境均接近于三角十二面体构型。荧光测试表明,1⁃Tb、1⁃Ho、1⁃Er和1⁃Tm均表现出了相应稀土离子的特征发射峰。此外,利用密度泛函理论计算分析了Hpmbp配体、dmbipy配体及稀土配合物的HOMO-LUMO信息。 展开更多
关键词 1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮 稀土配合物 荧光 密度泛函理论计算
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聚4-甲基-1-戊烯的制备及应用进展
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作者 杜文博 刘洋 +3 位作者 高建树 刘振宇 蒋文军 梁胜彪 《精细石油化工》 CAS 2023年第5期76-80,共5页
介绍了聚(4-甲基-l-戊烯)(PMP)制备以及其应用研究进展情况。根据不同的金属催化活性中心对催化剂进行分类概述;包括齐格勒-纳塔催化剂、茂金属催化剂、非茂金属催化剂、后过渡金属催化剂,指出了PMP工业化生产的最佳催化剂为齐格勒-纳... 介绍了聚(4-甲基-l-戊烯)(PMP)制备以及其应用研究进展情况。根据不同的金属催化活性中心对催化剂进行分类概述;包括齐格勒-纳塔催化剂、茂金属催化剂、非茂金属催化剂、后过渡金属催化剂,指出了PMP工业化生产的最佳催化剂为齐格勒-纳塔催化体系。此外对PMP聚合物的结晶性质以及聚合物的应用进展进行概述,对PMP聚合物的国产化发展进行评述和展望。 展开更多
关键词 催化剂 聚(4-甲基-1-戊烯) 结晶树脂 配位聚合
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聚-4-甲基-1-戊烯中空纤维膜式人工肺膜组件的氧气和二氧化碳传质性能研究
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作者 臧慧 樊文玲 李磊 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第5期858-864,共7页
采用自制的聚-4-甲基-1-戊烯中空纤维膜式人工肺组件,进行了氧气和二氧化碳传质性能研究.实验采用自制的模拟液循环装置,模拟液在膜丝外部流动,在氧气通入之前,用驱氧装置实现氧气的排出和二氧化碳的吸收,模拟静脉血,从而达到循环的效果... 采用自制的聚-4-甲基-1-戊烯中空纤维膜式人工肺组件,进行了氧气和二氧化碳传质性能研究.实验采用自制的模拟液循环装置,模拟液在膜丝外部流动,在氧气通入之前,用驱氧装置实现氧气的排出和二氧化碳的吸收,模拟静脉血,从而达到循环的效果.氧气在膜丝内部流动,经过膜组件部分溶解在膜丝外的模拟液中后,剩余氧气排出.模拟液选用去离子水、PBS缓冲溶液(78 v%PBS缓冲溶液,22 v%去离子水)、甘油-水溶液(50 wt%甘油,50 wt%去离子水)和亚硫酸钠水溶液(0.9 wt%亚硫酸钠,99.1 wt%去离子水).实验测定了在不同气-液流速、气相压力和气-液比下,氧气和二氧化碳的传质速率.实验测试表明,随着气-液流速增加,氧气和二氧化碳的传质效果明显增加,在去离子水中,在300mL·min^(-1)流速下,传质速率可达57.11 mL·min^(-1)·m^(-2)和103.59 mL·min^(-1)·m^(-2).随着气相压力的增加,氧气传质效果增速先增后减,逐渐趋于平衡,而二氧化碳的传质效果有所下降.随着气-液比的增加,氧气传质效果有所增加,而二氧化碳传质效果保持不变. 展开更多
关键词 聚-4-甲基-1-戊烯 膜式人工肺 氧气传质性能 二氧化碳传质性能 模拟液循环装置
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Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation 被引量:12
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作者 Longwei Lv Wenshu Ge +4 位作者 Yunsong Liu Guanyou Lai Hao Liu Wenyue Li Yongsheng Zhou 《Bone Research》 SCIE CAS CSCD 2016年第4期217-231,共15页
Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulatio... Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis. 展开更多
关键词 Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation OM stem BMD
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Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson’s disease 被引量:2
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作者 Wenbin Tu Furong Xu Guoguang Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第5期482-485,共4页
BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does ... BACKGROUND: To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson's disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP), does not exist. In addition, there are no reports of analysis of differential protein expression. OBJECTIVE: To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson's disease. DESIGN: Randomized controlled animal study. SETTING: Department of Neurology, the First Affiliated Hospital, Chongqing Medical University. MATERIALS: Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25 g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system (ChemiDoc XRS) by Bio-Rad, USA; and Voyager DE-PROMALD1-TOF-MS mass spectroscopy analyzer by AB1 Company, USA. METHODS: This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were received a subcutaneous injection of MPTP (25 mg&g), twice a week, for five successive weeks, to establish a chronic Parkinson's disease model. Mice in the control group received the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra. MAIN OUTCOME MEASURES: (1) 2-ED handbook (Bio-Rad Company) was referenced for two-dimensional electrophoresis, (2) PDQUEST8,0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. (3) Peptide mass finger print map and data were retrieved on http://www.prospector.ucsf.edu to compare differential substantia nigral protein expression in the two groups. RESULTS: Two-dimensional gel electrophoresis of substantia nigra tissue indicated that there were 33 differential protein expressions between the two groups. Three new proteins were evaluated, including α -enolase, which exhibited regulated expression, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. CONCLUSION: There are three proteins that exhibit differential expression in the substantia nigra- α -enolase, tumor necrosis factor ligand superfamily member 4, and cyclin-dependent kinase inhibitor 1B. 展开更多
关键词 Parkinson's disease 1-methyl-4-phenyl-l 2 3 6-tetrahydropyridine mice substantia nigra proteomics
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MORPHOLOGIES AND GAS SEPARATION PROPERTIES OF MELT-SPUN ASYMMETRIC POLY(4-METHYL-1-PENTENE)HOLLOW FIBER MEMBRANES 被引量:2
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作者 徐志康 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第3期369-372,共4页
Poly(4-methyl-1-pentene) (PMP) hollow fiber membranes were prepared by the melt-spun and cold-stretch(MSCS) method. Scanning electronic microscopy (SEM) was used to characterize the section and surface structures of t... Poly(4-methyl-1-pentene) (PMP) hollow fiber membranes were prepared by the melt-spun and cold-stretch(MSCS) method. Scanning electronic microscopy (SEM) was used to characterize the section and surface structures of themembranes with special asymmetric structure. The preliminary results of gas permeation measurements indicated that the resultant hollow fiber membranes have the potential ability for oxygen/nitrogen separation. 展开更多
关键词 Poly(4-methyl-1-pentene) Asymmetric membranes Hollow fiber membrane Gas permeation O_2/N_2 Separation
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Extraction Behavior of Rare Earths with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 Using Solid-liquid Extraction Technique 被引量:2
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作者 高锦章 潘仲巍 +2 位作者 杜新贞 康敬万 白光弼 《Rare Metals》 SCIE EI CAS CSCD 1993年第3期198-202,共5页
The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium... The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium extraction constants and pH_(1/2) values of solid-liquid extraction are higher than those of normal liquid-liquid extraction.The extraction efficiency tends to maximum when the ratio of phases is 1:1.When the extraction temperature is higher than the melting point of paraffin and the extraction time is over 10 min,the extraction efficiency keeps constant.Moreover,the relationship among separation factor,equilibrium extrac- tion constant,pH_(1/2) value and atomic number was obtained.The mechanism of solid-liquid extraction is analogous to that of liquid-liquid extraction. 展开更多
关键词 Solid-liquid extraction Rare earths 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5
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Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 被引量:4
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作者 孙凤梅 田孟魁 +1 位作者 杨靖华 连照勋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期789-792,共4页
The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its... The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1- with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6)A, α = 112.566(1), β = 92.324(2), γ = 102.91(1)°, V= 1315.65(10) A^3, Z = 2, Dc = 1.344 g/cm^3,μ(MoKa) = 0.282 mm^-1, λ = 0.71073 A, F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra- and intermolecular C( 12)-H(12)…O(1) and C(28)-H(28)...O(1)# 1 hydrogen bonds were observed in the title compound. 展开更多
关键词 trans-4-[ 5-(2 4-dichlorophenoxy)-3-methyl- 1-phenyl- 1H-pyrazol-4-yl)methylene amino]-1 5-dimethyl-2-phenyl-1 2-dihydropyrazol-3-one synthesis crystal structure
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1-methyl-4-phenylpyridinium ion induces endoplasmic reticulum stress through glycogen synthase kinase-3 beta activation in PC12 cells 被引量:1
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作者 Shengdong Wang Fucheng Luo Yan Chen Lei Qi Jie Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第11期805-810,共6页
1-methyl-4-phenylpyridinium ion (MPP^+) induces endoplasmic reticulum stress and activates caspase-12 in PC12 cells, leading to neuronal apoptosis. However, the underlying molecular mechanism remains unknown. The p... 1-methyl-4-phenylpyridinium ion (MPP^+) induces endoplasmic reticulum stress and activates caspase-12 in PC12 cells, leading to neuronal apoptosis. However, the underlying molecular mechanism remains unknown. The present study investigated the regulatory effects of nerve growth factor (Akt activator) and lithium chloride (glycogen synthase kinase-3β inhibitor) on the endoplasmic reticulum stress signaling pathway. The results revealed that MPP+ induced expression of Bip and C/EBP homologous protein. The upregulation of Bip and C/EBP homologous protein, as well as the decreased pro-caspase-12 level induced by MPP^+ were inhibited by pretreatment of the nerve growth factor or lithium chloride. These results suggest that the phosphatidylinositol 3 kinase-Aktglycogen synthase kinase-3β pathway is involved in MPP-induced endoplasmic reticulum stress. 展开更多
关键词 Parkinson's disease 1-methyl-4-phenylpyridinium ion endoplasmic reticulum stress glycogen synthase kinase-3β
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Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate 被引量:2
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作者 胡扬根 徐靖 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期689-692,共4页
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined... The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 展开更多
关键词 crystal structure ethyl 3-(4-ehlorophenyl)-3 4-dihydro-6-methyl-4-oxo-2- (pyrrolidin-1-yl)furo[2 3-d]pyrimidine-5-earboxylate aza-Wittig reaction synthesis
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Minocycline protects the apoptosis of PC12 cells induced by 1-methyl-4-phenylpyridinium 被引量:1
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作者 Wei SHEN Shenggang SUN Xuebing CAO 《Journal of Nanjing Medical University》 2005年第5期247-250,共4页
Objective: To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP^+ . Methods: Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP^+... Objective: To explore the protective effect of minocycline on the apoptosis of cellular parkinsonism models induced by MPP^+ . Methods: Using PC12 cells as the apoptotic model of dopaminergic neurons, MC and MPP^+ were added into the culture medium of PC12 cells, and using MTr to assay the cell viability and metabolic state; The cells apoptosis was assayed by electrophoresis method and using flow cytometry FACS to assay the apoptosis ratio. Results: Added the MPP^+ to get the concentration of 10μmol/L, the cellular parkinsonism model of apoptosis had been prepared. The pre-treatment of MC ( 100/μmol/L) could significantly increase the PC12 cell viability. The apoptosis ratio of MC+MPP^+ group was significantly lower than that of MPP^+ group, but was still significantly higher than that of control group. Conclusion: MC may protect the cell apoptosis induced by MPP^+ to some extent. 展开更多
关键词 MINOCYCLINE PC12 cell apoptosis parkinson disease 1-methyl-4-mhenylpyridinium
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3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸合成概述
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作者 成鸿静 钟若楠 +4 位作者 胡伟 曾敬 欧阳宇迪 刘源 蒋利 《精细化工中间体》 CAS 2023年第6期6-9,共4页
琥珀酸脱氢酶抑制剂(SDHI)类杀菌剂因其持效性和稳抗性显著,3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸作为该类杀菌剂的中间体在未来几十年具有相当广阔的市场前景。综合国内外文献研究,探讨了3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸各合成工艺... 琥珀酸脱氢酶抑制剂(SDHI)类杀菌剂因其持效性和稳抗性显著,3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸作为该类杀菌剂的中间体在未来几十年具有相当广阔的市场前景。综合国内外文献研究,探讨了3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸各合成工艺方法,并对比了各种方法的优缺点,对3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸合成方法的发展进行了展望。 展开更多
关键词 琥珀酸脱氢酶抑制剂 3-(二氟甲基)-1-甲基-1H-吡唑-4-羧酸 中间体
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