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工程教育中心何以推动科教融合——荷兰4TU工程教育中心的探索性单案例研究
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作者 魏丽娜 张炜 《中国高校科技》 2024年第1期60-66,共7页
工程教育中心作为建立在大学或研究机构中的跨学科交叉合作平台,是连接科学研究与教育实践的纽带,在高质量工程人才培养中发挥着重要作用。荷兰4TU工程教育中心利用4所顶尖理工大学在工程学科和教育领域的独特优势,积极与研发单位、教... 工程教育中心作为建立在大学或研究机构中的跨学科交叉合作平台,是连接科学研究与教育实践的纽带,在高质量工程人才培养中发挥着重要作用。荷兰4TU工程教育中心利用4所顶尖理工大学在工程学科和教育领域的独特优势,积极与研发单位、教育单位、企业部门合作,通过将前沿科学研究彻底融入工程课程设计、教学模式等多个方面,形成了独具一格的科教融合工程人才培养模式。文章从战略目标、组织架构、运行机制、质量保障4个维度详实分析了4TU工程教育中心推动科教融合的内在机制,总结归纳其在主题项目设置、教育共同体形成、课程体系迭代、创新网络构建、内外部质量保障等方面的核心特征,期望对我国科教融合的工程教育改革与建设有所启示。 展开更多
关键词 科教融合 4tu工程教育中心 组织架构 运行机制
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沉默TUFM通过AMPK/mTOR信号通路调控线粒体自噬对肺源性心脏病模型大鼠肺动脉高压的影响 被引量:1
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作者 崔本科 王岩 +2 位作者 卢云凤 杜鹃 翟羽涵 《疑难病杂志》 CAS 2024年第4期478-486,共9页
目的探讨线粒体翻译延伸因子Tu(TUFM)通过线粒体自噬促进肺动脉高压(PAH)血管重塑的作用机制。方法2022年1月—2023年6月于辽宁省人民医院中心实验室进行实验。将36只健康雄性Sprague-Dawley大鼠随机分为空白对照(Ctrl)组、模型(PAH)组... 目的探讨线粒体翻译延伸因子Tu(TUFM)通过线粒体自噬促进肺动脉高压(PAH)血管重塑的作用机制。方法2022年1月—2023年6月于辽宁省人民医院中心实验室进行实验。将36只健康雄性Sprague-Dawley大鼠随机分为空白对照(Ctrl)组、模型(PAH)组、TUFM过表达(OE)组、OE阴性对照(OE-NC)组、短发夹RNA(Sh)敲除TUFM(Sh)组和Sh-NC阴性对照(Sh-NC)组,每组6只。除Ctrl组外,其余大鼠均一次性腹腔注射1%野百合碱(60 mg/kg)诱导心源性肺水肿PAH大鼠模型;大鼠肺动脉平滑肌细胞(PASMC)在低氧(3%O 2)条件下培养24 h模拟体内肺动脉高压微环境,分为常氧(Norm)组、低氧(Hyp)组、小干扰RNA(SiRNA)-1组、SiRNA-2组、Si-NC组、OE-NC组和OE组。右心导管插管和脉冲多普勒超声检测大鼠肺血流动力学;苏木素-伊红染色检测肺小动脉病理结构;免疫荧光共染检测TUFM组织定位;细胞计数法检测细胞增殖;透射电镜观察线粒体结构和自噬小体;蛋白免疫印迹检测TUFM、自噬、凋亡和磷酸腺苷活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白表达。结果与Ctrl组比较,PAH组大鼠TUFM蛋白表达升高,且主要与PASMC标志物α平滑肌肌动蛋白(α-SMA)在肺小动脉内膜存在共定位,而与内皮细胞标志物CD31无共定位,肺动脉收缩压(PASP)升高,肺动脉血流加速时间(PAAT)缩短,远端肺小动脉管壁呈向心性增厚,管腔狭窄几乎堵塞,TUFM、苄氯素1重组蛋白(BECN1)、人微管相关蛋白轻链3(LC3)II/I和B淋巴细胞瘤2(Bcl2)蛋白表达升高,P62、Bcl2相关X蛋白(Bax)和凋亡酶激活因子(Apaf)蛋白表达降低(P<0.05);与PAH组比较,OE组PASP升高,PAAT缩短,肺小动脉管壁厚度升高,肺动脉TUFM、BECN1、LC3II/I和Bcl2表达升高,P62、Bax和Apaf表达降低(P<0.05);与PAH组比较,Sh组PASP降低,PAAT延长,肺小动脉管壁厚度和管腔狭窄度有所改善,TUFM、BECN1、LC3II/I和Bcl2表达降低,P62、Bax和Apaf表达升高(P<0.05)。与Norm组比较,Hyp组PASMC细胞TUFM蛋白表达升高;与Si-NC组细胞相比,SiRNA-1和SiRNA-2组P62、Bax蛋白表达升高,BECN1、LC3II/I、Bcl2、TUFM表达降低,线粒体结构完整,PASMC细胞增殖活性降低,细胞p-AMPK表达降低,p-mTOR表达升高(P<0.05);与OE-NC组比较,OE组细胞P62和Bax蛋白表达降低,BECN1、LC3II/I、Bcl2和TUFM表达升高,部分线粒体损伤崩解,嵴断裂消失,PASMC细胞增殖活性明显升高,细胞p-AMPK表达升高,p-mTOR表达降低(P<0.05)。结论沉默TUFM可通过激活AMPK/mTOR信号通路促进线粒体自噬加速PAH肺动脉平滑肌细胞凋亡。 展开更多
关键词 肺动脉高压 线粒体翻译延伸因子tu 平滑肌细胞 线粒体自噬 AMPK/mTOR通路 大鼠
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秦川牛宰后成熟过程中线粒体翻译延长因子Tu与能量代谢的关联性分析
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作者 司健芳 高爽 +2 位作者 张静 李亚蕾 罗瑞明 《食品科学》 EI CAS CSCD 北大核心 2024年第17期1-8,共8页
目的:线粒体翻译延长因子Tu(mitochondrial Tu translation elongation factor,TUFM)已被证明参与秦川牛宰后成熟过程中的细胞自噬活动,实验探究该过程中TUFM表达与能量代谢变化的关系。方法:以秦川牛背最长肌为研究对象,测定4℃不同成... 目的:线粒体翻译延长因子Tu(mitochondrial Tu translation elongation factor,TUFM)已被证明参与秦川牛宰后成熟过程中的细胞自噬活动,实验探究该过程中TUFM表达与能量代谢变化的关系。方法:以秦川牛背最长肌为研究对象,测定4℃不同成熟时间(0、2、12、24、48、96、144、192 h)TUFM表达量及含量、葡萄糖(glucose,GLU)、乳酸(lactic acid,LA)、腺苷三磷酸(adenosine triphosphate,ATP)、二磷酸腺苷(adenosine diphosphate,ADP)、单磷酸腺苷(adenosine monophosphate,AMP)6种物质含量以及乳酸脱氢酶(lactate dehydrogenase,LDH)、琥珀酸脱氢酶(succinate dehydrogenase,SDH)、磷酸丙糖异构酶(triose phosphate isomerase,TPI)、苹果酸脱氢酶(malate dehydrogenase,MDH)、细胞色素c氧化酶(cytochrome c oxidase,COX)5种酶活性的变化情况。结果:在秦川牛宰后成熟期间,GLU、ATP、ADP、AMP含量和LDH、SDH、TPI活性均呈下降趋势,TUFM表达量、MDH活性及LA和TUFM含量均呈先上升后下降趋势,COX活性呈先下降后上升再下降趋势。能量代谢各指标和TUFM蛋白主要在宰后初期发挥作用,对宰后初期及宰后中后期分别进行Pearson相关性分析,结果表明,在宰后初期牛背最长肌中TUFM表达量与MDH、LA呈极显著正相关(P<0.01),与ATP、ADP、AMP、LDH、SDH、TPI、COX、GLU呈极显著负相关(P<0.01)。在宰后中后期,TUFM表达与所有指标(GLU、LA、ATP、ADP、AMP、LDH、MDH、SDH、TPI、COX)均呈极显著正相关(P<0.01)。结论:在宰后初期TUFM表达量逐渐增加,可为肌肉细胞提供能量从而用于能量代谢途径,该过程可能是TUFM正向参与细胞自噬所致。在宰后中后期能量短缺时,TUFM可能抑制细胞自噬,优先将能量用于除细胞自噬外的其他重要途径(如能量代谢途径)以维持细胞稳态。综上,在宰后成熟过程中TUFM具有双重作用,可调节细胞自噬为能量代途径提供能量,有助于维持宰后能量代谢持续的时间。 展开更多
关键词 线粒体翻译延长因子tu 能量代谢 秦川牛 细胞自噬
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异氟烷麻醉对小鼠自发肌电及TUS/TMAS诱发肌电的影响
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作者 王茹茹 周晓青 +4 位作者 赵渝卉 刘煦 刘志朋 王欣 殷涛 《中国生物医学工程学报》 CAS CSCD 北大核心 2024年第1期10-17,共8页
经颅超声刺激(TUS)和经颅磁声耦合刺激(TMAS)调控运动皮层效果明显,但受限于清醒状态动物难以束缚,已有研究大多在麻醉状态下进行,对麻醉减弱调控效果的分析集中于中枢神经系统。本研究记录了异氟烷麻醉下24只小鼠的肢体自发肌电和TUS/T... 经颅超声刺激(TUS)和经颅磁声耦合刺激(TMAS)调控运动皮层效果明显,但受限于清醒状态动物难以束缚,已有研究大多在麻醉状态下进行,对麻醉减弱调控效果的分析集中于中枢神经系统。本研究记录了异氟烷麻醉下24只小鼠的肢体自发肌电和TUS/TMAS诱发肌电,定量分析了麻醉对自发肌电和诱发肌电发放率、潜伏期、时长和幅值的影响。结果显示,随着异氟烷输出浓度从0.40%增加至0.75%,每周期内小鼠自发肌电频次减少约50%,肌电发放时长变短,呈抑制状态;TUS/TMAS诱发肌电的成功率分别降低约50%和70%、潜伏期均延长约0.1 s、时长分别缩短约0.3和0.5 s,表明TUS/TMAS对运动皮层的调控效果随麻醉程度的加深而减弱。肢体自发和诱发肌电在发放率和时长上存在关联性特征,提示麻醉状态下小鼠自发肌电抑制状态可能是刺激效果减弱的影响因素之一。 展开更多
关键词 经颅超声刺激(tuS) 经颅磁声耦合刺激(TMAS) 肌电 麻醉
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绵羊肺炎支原体EF-Tu蛋白的原核表达及多克隆抗体制备
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作者 王永飞 邓博文 +5 位作者 刘晓艳 哈尔勒哈·阿曼太 郭嘉栋 周正国 蔡江 李有文 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第2期689-699,共11页
[目的]克隆绵羊肺炎支原体(Mycoplasma ovipneumoniae,Mo)EF-Tu基因,原核表达获得EF-Tu蛋白,制备抗EF-Tu蛋白的兔源多克隆抗体,为研究肺炎支原体EF-Tu蛋白的结构和功能奠定基础。[方法]采用重叠延伸PCR方法将pET-28a-EF-Tu质粒中EF-Tu... [目的]克隆绵羊肺炎支原体(Mycoplasma ovipneumoniae,Mo)EF-Tu基因,原核表达获得EF-Tu蛋白,制备抗EF-Tu蛋白的兔源多克隆抗体,为研究肺炎支原体EF-Tu蛋白的结构和功能奠定基础。[方法]采用重叠延伸PCR方法将pET-28a-EF-Tu质粒中EF-Tu基因中间的TGA密码子突变为TGG,并对测序结果与其他支原体参考株进行相似性比对和遗传进化分析,利用在线软件对其推测的蛋白序列进行生物信息学分析。将突变后的重组质粒转化大肠杆菌BL21(DE3)感受态细胞进行原核表达,经SDS-PAGE和Western blotting鉴定,利用镍柱亲和层析法纯化,以纯化的EF-Tu融合蛋白免疫家兔制备多克隆抗体,采用间接ELISA和Western blotting检测多克隆抗体效价及免疫反应性。[结果]试验成功突变了EF-Tu基因中TGA位点,并构建了融合表达His标签pET-28a-EF-Tu′原核表达载体。生物信息学分析表明,克隆的EF-Tu基因与绵羊肺炎支原体MoGH3-3菌株相似性最高,亲缘关系最近;编码387个氨基酸,无N-糖基化位点和跨膜区域,存在10个丝氨酸、20个苏氨酸、4个酪氨酸磷酸化位点,二级结构由无规则卷曲(35.14%)、α-螺旋(26.87%)、延伸链(26.87%)及β-转角(11.11%)构成。SDS-PAGE和Western blotting结果显示,目的蛋白大小约为43 ku,蛋白纯化浓度为0.615 g/L。ELISA和Western blotting结果显示,制备的多克隆抗体效价可达1∶128 000,能够特异性识别EF-Tu融合蛋白,具有良好的免疫反应性。[结论]本研究成功突变了EF-Tu基因的TGA密码子,原核表达并纯化获得EF-Tu融合蛋白,制备其多克隆抗体效价为1∶128 000,为后续研究肺炎支原体EF-Tu蛋白结构和生物学功能及其疫苗研发提供了试验基础。 展开更多
关键词 绵羊肺炎支原体 重叠延伸PCR EF-tu基因 多克隆抗体
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Synthesis of Novel Non-Nucleoside HIV-1 Reverse Transcriptase Inhibitors-1-(3-Phthalimido-2-oxobutyl)-4-Substituted-phenylpiperazines
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作者 Xin CHEN Lin WANG +3 位作者 Zhi Zhong ZHAO Xing Quan ZHANG Xiang Hong CHEN Hong Shan CHEN(Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050 Institute of Medicinal Biotechnology, Chinese Academy of M 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第7期571-572,共2页
We have designed and synthesized a series of new phthalimidopiperazines, biological activity test show that the target compounds(Ic, Ie, ii) can inhibit HIV-I RT with IC50 20.0, 43.8, and 63.7 mu M, respectively.
关键词 piperazinE PHTHALIMIDE HIV1-RT inhibitor
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The water-soluble TF3 component from Eupolyphaga sinensis Walker promotes tibial fracture healing in rats by promoting osteoblast proliferation and angiogenesis
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作者 Binghao Shao Xing Chen +7 位作者 Jin'ge Du Shuang Zou Zhaolong Chen Jing Wang Huaying Jiang Ruifang Lu Wenlan Wang Chunmei Wang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期245-254,共10页
Objective To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods A modified Einhorn method was used to develop a rat t... Objective To determine the active components of Eupolyphaga sinensis Walker(Tu Bie Chong)and explore the mechanisms underlying its fracture-healing ability.Methods A modified Einhorn method was used to develop a rat tibial fracture model.Progression of bone healing was assessed using radiological methods.Safranin O/fast green and CD31 immunohistochemical staining were performed to evaluate the growth of bone cells and angiogenesis at the fracture site.Methylthiazoletetrazolium blue and wound healing assays were used to analyze cell viability and migration.The Transwell assay was used to explore the invasion capacity of the cells.Tubule formation assays were used to assess the angiogenesis capacity of human vascular endothelial cells(HUVECs).qRT-PCR was used to evaluate the changes in gene transcription levels.Results Tu Bie Chong fraction 3(TF3)significantly shortened the fracture healing time in model rats.X-ray results showed that on day 14,fracture healing in the TF3 treatment group was significantly better than that in the control group(P=.0086).Tissue staining showed that cartilage growth and the number of H-shaped blood vessels at the fracture site of the TF3 treatment group were better than those of the control group.In vitro,TF3 significantly promoted the proliferation and wound healing of MC3T3-E1s and HUVECs(all P<.01).Transwell assays showed that TF3 promoted the migration of HUVECs,but inhibited the migration of MC3T3-E1 cells.Tubule formation experiments confirmed that TF3 markedly promoted the ability of vascular endothelial cells to form microtubules.Gene expression analysis revealed that TF3 significantly promoted the expression of VEGFA,SPOCD1,NGF,and NGFR in HUVECs.In MC3T3-E1 cells,the transcript levels of RUNX2 and COL2A1 were significantly elevated following TF3 treatment.Conclusion TF3 promotes fracture healing by promoting bone regeneration associated with the RUNX2 pathway and angiogenesis associated with the VEGFA pathway. 展开更多
关键词 tu Bie Chong Water-solube component Fracture RATS OSTEOBLAST ANGIOGENESIS
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An Investigation of Moxibustion Treatment for Abscesses in the Song Dynasty:Focusing on the“Jiu Ai Tu”
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作者 WANG Li 《Chinese Medicine and Culture》 2024年第3期241-250,共10页
Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its r... Jiu Ai Tu(The Moxa Treatment)from the Song dynasty is the earliest surviving painting that focuses on the subject of acupuncture and moxibustion.This paper takes the medical activities depicted in the artwork as its research object and systematically analyzes the external treatment methods for abscesses during the Song dynasty reflected in Jiu Ai Tu.By examining the understanding of abscesses during that period,the paper explores the level of development in external medicine techniques.By analyzing the medical awareness and behaviors of patients when facing such severe illnesses,it aims to explore the societal cognition and experiences regarding health and disease.The paper attempts to present the folk medical ecology of the Song dynasty represented by Jiu Ai Tu. 展开更多
关键词 Jiu Ai tu ABSCESS Moxibustion method Traditional Chinese medicine Chinese external medicine
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Kinetic and Mechanistic Study of Oxidation of Piperazines by Bromamine-T in Acidic Medium
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作者 Chandrashekar   B. M. Venkatesha +1 位作者 S. Ananda Netkal M. Made Gowda 《Modern Research in Catalysis》 2013年第4期157-163,共7页
Oxidations of piperazine, 1-methylpiperazine and 1-ethylpiperazine by bromamine-T (BAT) in buffered acidic medium have been kinetically studied at 303 K. The reaction shows a first-order dependence of the rate each on... Oxidations of piperazine, 1-methylpiperazine and 1-ethylpiperazine by bromamine-T (BAT) in buffered acidic medium have been kinetically studied at 303 K. The reaction shows a first-order dependence of the rate each on [BAT]0 and [piperazine]0, and an inverse fractional-order dependence on [H+]. The additions of halide ions and the reduction product of BAT, p-toluenesulfonamide, have no effect on the reaction rate. The variation of ionic strength of the solvent medium has no influence on the rate. Activation parameters have been evaluated from the Arrhenius and Eyring plots. A common mechanism consistent with the kinetic data has been proposed for all piperazines. The protonation constants of substrates have been evaluated. The Hammett linear free-energy relationship has been observed for the reaction with ρ = ?0.5 indicating that the electron-donating groups enhance the reaction rate by stabilizing the transition state. An isokinetic relationship observed shows β = 368 K indicating the dominance of enthalpy factors on the reaction rate. 展开更多
关键词 piperazines OXIDATION KINETICS MECHANISM Bromamine-T BUFFER
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Determination of Piperazine Ferulate in Human Plasma by HPLC and Its Pharmacokinetic Study 被引量:1
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作者 袁桂艳 王本杰 +2 位作者 魏春敏 刘焕君 郭瑞臣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期238-242,共5页
Aim To establish a sensitive HPLC method for determination of piperazine ferulate and to study its pharmacokinetics in healthy volunteers. Methods Piperazine ferulate was separated on a Shimadzu C_ 18 column with acet... Aim To establish a sensitive HPLC method for determination of piperazine ferulate and to study its pharmacokinetics in healthy volunteers. Methods Piperazine ferulate was separated on a Shimadzu C_ 18 column with acetic acid (0.1%)-methanol (60 ∶ 40, V/V) as mobile phase after liquid-liquid extraction, and detection was performed at 310 nm. Piperazine ferulate pharmacokinetic parameters after a single oral dose of 200 mg of piperazine ferulate dispersible tablets in 20 healthy male volunteers were calculate... 展开更多
关键词 piperazine ferulate dispersible tablet PHARMACOKINETICS HPLC
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TU1无氧铜/316L不锈钢电子束焊接接头组织与性能
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作者 尹中会 曹志森 +2 位作者 杨建军 马建国 刘振飞 《黑龙江工业学院学报(综合版)》 2023年第5期114-119,共6页
采用真空电子束焊分别对2mm、3mm、5mm不同厚度的TU1无氧铜板材和316L不锈钢板材进行异种材料焊接,并对焊接接头的显微组织和力学性能进行了研究。实验结果表明:焊缝区和热影响区呈现波浪形状,焊缝区存在不同程度的混合组织,接头母材区... 采用真空电子束焊分别对2mm、3mm、5mm不同厚度的TU1无氧铜板材和316L不锈钢板材进行异种材料焊接,并对焊接接头的显微组织和力学性能进行了研究。实验结果表明:焊缝区和热影响区呈现波浪形状,焊缝区存在不同程度的混合组织,接头母材区及热影响区的晶粒大小随铜钢板材厚度的增加而增加。TU1热影响区的晶粒明相比母材区,明显增大。焊缝区的硬度高于母材区。在电子束电流为10mA,加速电压为150kV,焊接速度为15mm/s的焊接参数下,2mm、3mm、5mm厚的接头抗拉强度分别是263MPa、174MPa、141MPa。2mm厚的拉伸式样断裂发生在TU1热影响区,而3mm和5mm厚拉伸式样断裂发生在焊缝处,即2mm厚的TU1无氧铜板材和316L不锈钢板材焊接接头抗拉性能最好。 展开更多
关键词 tu1无氧铜 316L不锈钢 电子束焊接 微观组织 力学性能
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Crystal Structures, Stability, and Solubility Evaluation of a 2:1 Diosgenin-Piperazine Cocrystal 被引量:7
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作者 Ningbo Gong Hongmei Yu +4 位作者 Ying Wang Cheng Xing Kun Hu Guanhua Du Yang Lu 《Natural Products and Bioprospecting》 CAS 2020年第4期261-267,共7页
A cocrystal of diosgenin with piperazine in 2:1 stoichiometry was successfully synthesized.The solid form was prepared by liquid assisted grinding,slurry and crystallization methods.The cocrystal was characterized by ... A cocrystal of diosgenin with piperazine in 2:1 stoichiometry was successfully synthesized.The solid form was prepared by liquid assisted grinding,slurry and crystallization methods.The cocrystal was characterized by powder X-ray diffraction,differential scanning calorimetry,thermogravimetric analysis,Fourier transform infrared spectroscopy,and structure determined by single crystal X-ray diffraction,the hydrogen bonds formed into fish bone structure along the[010]direction and all the molecules packed into 3D layer structure along a axis.After formation of cocrystal,the solubility of diosgenin was improved,and the solubility value in 0.2%SDS solution was approximately 1.5 times as large as that of the parent material. 展开更多
关键词 DIOSGENIN piperazinE COCRYSTAL Characterization SOLUBILITY
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Experimental studies and artificial neural network modeling of surface tension of aqueous sodium L-prolinate solutions and piperazine blends
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作者 Muhammad Shuaib Shaikh A.M.Shariff +4 位作者 M.A.Bustam Sahil Garg Khadija Qureshi Pervez Hameed Shaikh Inamullah Bhatti 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1904-1911,共8页
The surface tension study is very crucial for the design of CO2 gas absorption contacting equipment. The significance of the surface tension has been increasing due to its consideration in various technological fields... The surface tension study is very crucial for the design of CO2 gas absorption contacting equipment. The significance of the surface tension has been increasing due to its consideration in various technological fields. This property influences the mass transfer and hydrodynamics of gas absorption systems, mainly multiphase systems, in which the interface between gas and liquid exists. Therefore, in this study, surface tension of aqueous solutions of sodium L-prolinate(SP) and piperazine(PZ) blends were measured at ten different temperatures from(298.15 to 343.15) K. The SP mass fractions were 0.10, 0.20, and 0.30;while the mass fractions of PZ were 0.02 and 0.05. The experimental results showed that the surface tension increase with increasing the mass fractions of SP and PZ in aqueous blends, and decrease linearly with rising temperature. The experimental data of surface tension were correlated by two empirical correlations as a function of temperature and mass fractions for estimating the predicted data using the optimized correlation coefficients. Moreover, the modeling of surface tension data was carried out using Artificial Neural Network(ANN) approach. The results obtianed from ANN modeling were compared with applied empirical correlation. It was found that the ANN approach outperformed the empirical correlation used in this study. Besides, a quantitative analysis of variation(ANOVA) was performed in order to determine the significance of data. The surface tension of aqueous SP and SP + PZ was also compared with various conventional solvents. 展开更多
关键词 Surface tension L-Prolinate piperazinE Correlation Prediction Neural network
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Syntheses, Structures and Fluorescent Property of Two Cd(Ⅱ) 3D Coordination Polymers with Mixed Ligands of Azide and Piperazine Derivatives
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作者 都凤磊 李志华 +1 位作者 林平 杜少武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第11期1657-1661,共5页
Two new coordination polymers, [Cd(N3)2(Baep)l/2]n (1) and [Cd2(N3)4(CH3OH)(Bapp)I/.2]n (2) (Baep = 1,4-bis(2-aminoethyl)piperazine, Bapp = 1,4-bis(3-aminopropyl)piperazine) were synthesized. The c... Two new coordination polymers, [Cd(N3)2(Baep)l/2]n (1) and [Cd2(N3)4(CH3OH)(Bapp)I/.2]n (2) (Baep = 1,4-bis(2-aminoethyl)piperazine, Bapp = 1,4-bis(3-aminopropyl)piperazine) were synthesized. The crystal of 1 is of monoclinic system, space group P21/c with a = 9.341(7), b = 11.677(9), c = 8.195(6) A, fl = 93.925(13), V= 891.8(11) A3, Z= 4, μ(MoKa) = 2.42 mm-1, Mr = 280.58, Dc = 2.090 g/cm3, the final R = 0.0297 and wR = 0.0720. The crystal of 2 is of triclinic system, space group PI with a = 9.121(5), b = 9.666(5), c = 10.250(6) A, a = 72.91(2), β= 77.10(2), V = 73.95(2)°, V = 820.0(8)°, Z = 2,μ(MoKa) = 2.62 mm-1, Mr= 522.10, Dc = 2.114 g/cm3, the final R = 0.0251 and wR = 0.0632. Single-crystal X-ray diffraction studies reveal that 1 is a 3D structure based on a dinuclear unit {Cd2(N3)a(Baep)}, in which the Baep ligands formed in situ display two different bridging modes. Compound 2 also has a 3D structure based on a tetranuclear cluster {Cda(N3)8(CH3OH)2(Bapp)}, in which the azido anions exhibit four different bridging modes (μ-1,1, μ-1,3, μ-l,l,1 and μ-1,1,3). The thermal stability and fluorescent property of 1 and 2 have also been investigated. 展开更多
关键词 cadmium azide piperazine derivatives in situ reaction FLUORESCENCE
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Synthesis of Some <i>N</i>-[(4-Substituted-1-Piperazinyl)-Oxo(Alkyl and Ethylcarbamoyl)]-3-(2-Thiophenyl)Acrylamides as Non-Steroidal Anti-Allergic and Anti-Inflammatory Agents
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作者 Osama I. Abd El-Salam Ahmed M. Shalaby +2 位作者 Abdulah A. El-Sawy Soha Elshihaby Mohamed Abdulla 《Open Journal of Synthesis Theory and Applications》 2013年第2期63-72,共10页
An interesting approach for the design of anti-allergies is rationally considered. It was proved that current anti-allergic drugs comprise piperazine and acrylic acid segments. In harmony with these findings, new prod... An interesting approach for the design of anti-allergies is rationally considered. It was proved that current anti-allergic drugs comprise piperazine and acrylic acid segments. In harmony with these findings, new products 5a-u were synthesized starting from conjugated 2-thiopheneacrylic acid with amino acid esters3a-g followed by coupling of their acid derivatives4a-g with some piperazine segments, with the aim to increase their biological activities and decrease side effects. The anti-allergic and anti-inflammatory activities of the products were evaluated and promising results were obtained. 展开更多
关键词 Thiophene Amino Acids piperazines ANTI-ALLERGY Ant-Inflammatory
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Synthesis and antifungal activity of 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-(4-substituted acyl piperazin-1-yl)-2-propanols
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作者 梁爽 刘超美 +3 位作者 朱杰 何秋琴 姜远英 曹永兵 《Journal of Medical Colleges of PLA(China)》 CAS 2004年第3期142-145,共4页
Objective: To study the effect of fluconzole derivatives from a side chain containing 4-substituted acyl piperazin-1-yl on antifungal activity. Methods: Fourteen title compounds were synthesized and confirmed by the e... Objective: To study the effect of fluconzole derivatives from a side chain containing 4-substituted acyl piperazin-1-yl on antifungal activity. Methods: Fourteen title compounds were synthesized and confirmed by the elementary analysis, 1HNMR and IR spectra. Five deep fungal strains and 3 shallow fungal strains were chosen as the experimental strains.Minimum inhibitory concentrations(MICs) of all title compounds were determined by the method recommended by the National Committee for Clinical Laboratory Standards (NCCLS) using RPMI 1640 test medium. Results: Among the 14 title compounds, 12 were first reported. The results of preliminary antifungal test showed that all the title compounds exhibited potent antifungal activities to a certain extent. The activity of 4 compounds were more than 4 times as high as that of fluconazole and equal to that of ketoconazole against Candida albicans in vitro(MIC 80 value≤0.125 μg/ml). Conclusion: Introduction of a side chain containing 4-substituted acyl piperazin-1-yl into the main part of fluconazole has important influence on antifungal activities of title compounds. 展开更多
关键词 triazolanol compounds piperazinE SYNTHESIS antifungal activity in vitro structure-activity relationship
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Structural Characterization and Proton-conductive Property of a Lanthanide Metal-organic Framework Assembled from 1,2,4,5-Benzenetetracarboxylic Acid and Piperazine
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作者 梁晓强 樊增禄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第6期977-984,共8页
The reaction of Pr(Ⅲ) salt with 1,2,4,5-benzenetetracarboxylic acid(H4betc) and piperazine(pip) yielded a lanthanide metal-organic framework {[Pr(betc)(H2O)2](H2pip)0.5}n(1)under hydrothermal conditions... The reaction of Pr(Ⅲ) salt with 1,2,4,5-benzenetetracarboxylic acid(H4betc) and piperazine(pip) yielded a lanthanide metal-organic framework {[Pr(betc)(H2O)2](H2pip)0.5}n(1)under hydrothermal conditions. Compound 1 was characterized by single-crystal X-ray structural analysis, elemental analysis, IR, X-ray powder diffraction, and thermal gravimetric. Compound 1crystallizes in monoclinic, space group P21/n with a = 11.023(5), b = 11.109(5), c = 11.456(5) A, β = 110.065(5)°, V = 1317.7(9) A3, Mr = 471.14, Z = 4, F(000) = 920, Dc = 2.375 g/cm^3, μ(Mo Kα) = 3.761 mm-1, the final R = 0.0286 and w R = 0.0821(I 〉 2σ(I)). Compound 1 exhibits a 2D network with(4, 4) topology, and a 3D supramolecular framework formed by hydrogen-bonding interactions. The proton conductivity of compound 1 has been investigated at ~97% relative humidity and different temperature. 展开更多
关键词 lanthanide metal-organic framework 1 2 4 5-benzenetetracarboxylic acid protonated piperazine hydrogen bond proton conductivity
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延伸因子Tu GTP结合域蛋白2功能研究进展
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作者 蓝金鑫 刘羽阳 +2 位作者 刘嘉霖 吴海涛 陈凌 《解放军医学院学报》 CAS 北大核心 2023年第10期1157-1161,共5页
延伸因子Tu GTP结合域蛋白2(elongation factor Tu GTP binding domain containing protein,EFTUD2)是剪接体复合物U5小核糖核蛋白的核心组件,通过调节剪接体的剪接功能进而调控相关基因的表达。本文旨在总结EFTUD2在免疫调节、胚胎发... 延伸因子Tu GTP结合域蛋白2(elongation factor Tu GTP binding domain containing protein,EFTUD2)是剪接体复合物U5小核糖核蛋白的核心组件,通过调节剪接体的剪接功能进而调控相关基因的表达。本文旨在总结EFTUD2在免疫调节、胚胎发育和肿瘤进展等方面的重要作用。 展开更多
关键词 延伸因子tu GTP结合域蛋白2 剪接体 胚胎发育 肿瘤进展 免疫调节
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New Photometric Investigations of G-type Contact Binary TU Boo
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作者 Jing-jing Wang Meng Guo +1 位作者 Lin-qiao Jiang Bin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第4期103-109,共7页
Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights o... Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G. 展开更多
关键词 (stars:)binaries eclipsing-stars solar-type-stars individual(tu Boo)
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河北赤城话“VP+tu■^(53)”结构
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作者 李文张 张学敏 《吉林省教育学院学报》 2023年第6期180-186,共7页
河北赤城话中“VP+tu■^(53)”结构表示未然、假设等语义,在对VP的选择上,动作动词、存现动词、趋向动词、能愿动词可以进入此结构,动宾短语、状中短语、动补短语、连动短语可以进入此结构,自主性动词和非自主性动词都可以进入,动态形... 河北赤城话中“VP+tu■^(53)”结构表示未然、假设等语义,在对VP的选择上,动作动词、存现动词、趋向动词、能愿动词可以进入此结构,动宾短语、状中短语、动补短语、连动短语可以进入此结构,自主性动词和非自主性动词都可以进入,动态形容词也可以进入此结构。“VP+tu■^(53)”结构主要有VP+tu■^(53)、VO+tu■^(53)、V+tu■^(53)+O、VC+tu■^(53)、VC+O+tu■^(53)等格式类型。“VP+tu■^(53)”结构在时体意义上有将要开始、将要完成等表示未然的意义,在语义上表示条件关系和假设关系。与“的时候”相比,“VP+tu■^(53)”结构语法位置自由度高,语义内涵较为狭窄,在语言使用上存在代际差异。 展开更多
关键词 VP+tu?53 河北赤城话 语法化
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