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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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绵羊肺炎支原体EF-Tu蛋白的原核表达及多克隆抗体制备 被引量:2
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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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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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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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SYNTHESIS AND STRUCTURE-ACTIVITY STUDIES OF SUBSTITUENT 1-(O-CHLOROBENZOYL)-3-(PHENYL) THIOUREA LARVIClDES
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作者 陆忠娥 孙大庆 李凯 《苏州大学学报(自然科学版)》 CAS 1990年第2期238-242,共5页
In this paper, we synthesized nineteen substituent 1-(o-chloro-benzoyl)-3-(phenyl) thiourea derivatives and studied their structure activity relationship, We found that the compounds with electron-withdrawing group (F... In this paper, we synthesized nineteen substituent 1-(o-chloro-benzoyl)-3-(phenyl) thiourea derivatives and studied their structure activity relationship, We found that the compounds with electron-withdrawing group (F) would have higher insecticidal activity. 展开更多
关键词 硫脲 杀虫剂 活性 苯甲酰
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Effect of N-substituents on performance of thiourea collectors by density functional theory calculations 被引量:14
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作者 刘广义 钟宏 +2 位作者 夏柳荫 王帅 戴塔根 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期695-701,共7页
Using density functional methods,some properties were studied such as the energies and compositions of frontier molecular orbitals and the atomic charges,which are related to the reactive behavior of thioureas contain... Using density functional methods,some properties were studied such as the energies and compositions of frontier molecular orbitals and the atomic charges,which are related to the reactive behavior of thioureas containing different N-substituent groupings.The calculation results indicate that the N-substituent groupings have significant effect on the flotation performance of thiourea collectors.The order of electron-donating ability is N-propyl-N'-benzyl-thiourea(PBZYTU)>N-propyl-N'-ethyl-thiourea (PETU)>N-propyl-N'-allyl-thiourea(PALTU)>>N-propyl-N'-acetyl-thiourea(PACTU)>N-propyl-N'-ethoxycarbonyl-thiourea (PECTU)>N-propyl-N'-benzoyl-thiourea(PBZOYTU),and the order of feedback-electron-accepting ability is PBZOYTU> PACTU>PECTU>>PALTU>PETU>PBZYTU.This implies that PBZOYTU,PACTU or PECTU can react with copper atoms having(t2g) 6 (eg) 3Cu(II)or t 6e 4Cu(I)configuration on the surfaces of copper sulfide minerals through normal covalent bond and back donation covalent bond,and exhibit excellently collecting performance for copper sulfide minerals.These are consistent with the experimental data reported in the literatures. 展开更多
关键词 thiourea collector sulfide ore structure-activity relationship density functional method
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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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Synthesis and Herbicidal Activities of N'-(substituted pyrimidin-2-yl)-N-Substituted Phenoxyacetyl Thiourea Derivatives 被引量:2
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作者 Si Jia XUE Jin Shan ZOU Hai Jian YANG (Department of Chemistry, Central China Normal University, Wuhan 430079) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期19-20,共2页
Fifteen N'-(substituted pyrimidin-2-y1)-N-substituted phenoxyacetyl thioureas were synthesized and tested for biological activities. All of them are new compounds and their structures were confirmed by IR. IHNMR. ... Fifteen N'-(substituted pyrimidin-2-y1)-N-substituted phenoxyacetyl thioureas were synthesized and tested for biological activities. All of them are new compounds and their structures were confirmed by IR. IHNMR. MS and elemental analysis. Some of the target compounds showed excellent inhibitory activities against root and stalk of dicotyledon plant (such as radish). and selective on monoctyledon plant (such as rice). 展开更多
关键词 4-Nitrophenoxyacetyl thiourea 2 4-dichlorophenoxyacetyl thiourea SYNTHESIS 2-chlorophenoxyacetyl thiourea 2-amino pyrimidine herbicidal activity
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Synthesis and Crystal structure of Bis- (thiourea)dichloroiron(II) Di(4,5-diazafluoren-9-one) 被引量:3
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作者 WUZhi-Yong XUDuan-Jun +1 位作者 WUJing-Yun CHIANGMichaelY 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1238-1241,共4页
The title compound Fe(CH4N2S)2Cl22(C11H6N2O) (Mr = 643.35) has been prepared and its crystal structure was determined by X-ray diffraction method with the following data: triclinic, space group P1, a = 7.3742(10), b =... The title compound Fe(CH4N2S)2Cl22(C11H6N2O) (Mr = 643.35) has been prepared and its crystal structure was determined by X-ray diffraction method with the following data: triclinic, space group P1, a = 7.3742(10), b = 13.0427(12), c = 15.215(2) , a = 88.969(12), b = 78.004(12), g = 79.689(11)o, V = 1408.1(3) 3, Z = 2, Dx = 1.517 g/cm3, m = 0.912 mm-1 and F(000) = 656. The final R = 0.030 and wR = 0.078 for 4070 observed reflections (I > 2s(I)), and R = 0.064 and wR = 0.091 for 5516 independent ones. The crystal consists of tetrahedral Fe(II) complex and hydrogen bonded 4,5-diazafluoren-9-one (dafone). The carbonyl bridge in dafone distorts the bipyridine moiety and results in the longer N…N separation of 3.071(3) and 3.061(3) ? There exists an extensive intermolecular hydrogen bond network in the crystal, and p-p stacking is observed between the neighboring dafone rings. 展开更多
关键词 Fe(II) complex thiourea crystal structure synthesis 4 5-diazafluoren-9-one
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Crystal Structure and Biological Activities of N-(5-(4-Chloro-2-(trifluoromethyl)phenyl)furan-2-carbonyl)-N'-(4,6-dimethylpyrimidin-2-yl)thiourea 被引量:3
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作者 阎琳 薛思佳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期543-546,共4页
The new title compound N-(5-(4-chloro-2-(trifluoromethyl)phenyl)furan-2-carbon-yl)- N'-(4,6-dimethylpyrimidin-2-yl)thiourea (C19H14C1F3N4O2S) has been synthesized, and its crystal structure and biological b... The new title compound N-(5-(4-chloro-2-(trifluoromethyl)phenyl)furan-2-carbon-yl)- N'-(4,6-dimethylpyrimidin-2-yl)thiourea (C19H14C1F3N4O2S) has been synthesized, and its crystal structure and biological behaviors were studied. The title compound crystallizes in the monoclinic system, space group P21/c with a = 7.932(5), b = 33.46(2), c = 7.556(5) A, β = 98.058(9)°, V = 1986(2) A^3 Mr = 454.85, Z = 4, Dc = 1.521 g/cm^3, μ = 0.349 mm^-1 and F(000) = 928. The structure was solved by direct methods and refined to R = 0.0724 and wR= 0.1429 for 3494 observed reflections (I 〉 2σ(I)). Intermolecular hydrogen bonds along the b axis together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary biological tests show definite herbicidalactivity for the title compound. 展开更多
关键词 5-substitutedphenyl-2-furoyl thiourea derivatives crystal structure herbicidal activity
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Study on Mechanism of Gold Leaching by Thiourea in the Presence of Sodium Sulphite 被引量:1
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作者 HU Yue-hua GUO Guang-fa QIU Guan-zhou 《Journal of Central South University》 SCIE EI CAS 2000年第3期113-116,共4页
The linear potential sweep voltammetry and electrochemical methods were used to study the mechanism and kinetics of gold dissolution in thiourea solution in the absence and presence of sodium sulphite.The results show... The linear potential sweep voltammetry and electrochemical methods were used to study the mechanism and kinetics of gold dissolution in thiourea solution in the absence and presence of sodium sulphite.The results show that in the absence of sodium sulfite the dissolution rate of gold in thiourea solution is relatively slow and it increases with the increase of the concentration of thiourea and decreases with pH. Thiourea is easily oxidized to formamidine disulphide, which reduces the leaching efficiency and increases reagent consumption. In the presence of sodium sulphite, the effective concentration of thiourea is increased and the dissolution rate of gold in thiourea solution is greatly increased. The activation energy required for gold dissolution in thiourea solution with sodium sulphite is 20.9 kJ·mol -1 which is much lower than 55.0 kJ·mol -1 in the absence of sodium sulphite. It is evident that sodium sulphite has a significant effect on the electrochemical reaction kinetics of gold in thiourea solution. 展开更多
关键词 GOLD LEACHING thiourea SODIUM SULPHITE MECHANISM
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Raman Spectroscopic Studies on the Complexation and Adsorbed Behaviour of Thiourea 被引量:1
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作者 Tian Zhongqun (Department of Chemistry, Xiamen University, Xiamen)Fleischmann, Martin (Department of Chemistry, Uneversity of Soutbamptoe, England) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第3期265-269,共5页
Raman spectroscopic studies on thiourea (TU) in highly acidic media (e. g. >3 mol/L HC1O4) show that TU as a solution species is protonated through its sulphur atom and forms complex with anions. However, as an ads... Raman spectroscopic studies on thiourea (TU) in highly acidic media (e. g. >3 mol/L HC1O4) show that TU as a solution species is protonated through its sulphur atom and forms complex with anions. However, as an adsorbed species, TU is protonated via the nitrogen atom and adsorbed at the silver electrode surface through the sulphur atom. The distinct effects of pH and anions of the solution on the surface enhanced Raman (SER) spectra of TU were investigated. In acidic and neutral solutions, TU is coadsorbed with anions through its NH3+ and - NH2 groups respectively. 展开更多
关键词 Raman spectroscopy thiourea ADSORPTION
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Resonance Raman Spectroscopic and Theoretical Study of Geometry Distortion of Thiourea in 2^1A State
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作者 张海波 赵彦英 郑旭明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第1期1-10,I0003,共11页
The A-band resonance Raman spectra of thiourea were obtained in water and acetonitrile solution. B3LYP/6-311++G(3df,3pd) and RCIS/6-311++G(3df,3pd) calculations were done to elucidate the ultraviolet electroni... The A-band resonance Raman spectra of thiourea were obtained in water and acetonitrile solution. B3LYP/6-311++G(3df,3pd) and RCIS/6-311++G(3df,3pd) calculations were done to elucidate the ultraviolet electronic transitions, the distorted geometry structure and the saddle point of thiourea in 21A excited state, respectively. The resonance Raman spectra were assigned. The absorption spectrum and resonance Raman intensities were modeled using Heller's time-dependent wavepacket approach to resonance Raman scattering. The results indicate that largest change in the displacement takes place with the C--S stretch mode u6 (|△|=0.95) and noticeable changes appear in the H5N3H6+H8N4H7 wag v5 (|△|=0.19), NCN symmetric stretch^-C--S stretch+N3H6+H8N4 wag v4 (|△|=0.18), while the moderate intensities of 2-15 and 4-15 are mostly due to the large excited state frequency changes of v15, but not due to its significant change in the normal mode displacement. The mechanism of the appearance of even overtones of the S-CN2 out of plane deformation is explored. The results indicate that a Franck-Condon region saddle point is the driving force for the quadric phonon mechanism within the standard A-term of resonance Raman scattering, which leads to the pyramidalization of the carbon center and the geometry distortion of thiourea molecule in 21A excited state. 展开更多
关键词 thiourea Excited state structural dynamics Resonance Raman Timedependent wavepacket approach Density functional theory
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Organic Reactions in Ionic Liquids:Ionic Liquid-promoted EfficientSynthesis of Disubstituted and Trisubstituted Thioureas Derivatives 被引量:1
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作者 ZhangGaoLE ZhenChuCHEN +1 位作者 YiHU QinGuoZHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期201-204,共4页
In ionic liquid [Bmim][BF4], a series of disubstituted and trisubstituted thiourea derivativeswere synthesized from phenyl and butyl isothiocyanate with a variety of amine in excellent yield.
关键词 Phenyl isothiocyanate butyl isothiocyanate thiourea ionic liquid.
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Analysis of Intra-and Intermolecular Hydrogen Bonds and Quantum Chemical Calculations on 1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea 被引量:1
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作者 乔磊 黄洁 +4 位作者 胡伟 张玉 秦宝福 宋纪蓉 高原 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第11期1759-1770,共12页
1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea, C15H10F4N2OS, has been synthesized firstly and determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system... 1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea, C15H10F4N2OS, has been synthesized firstly and determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group C2/c with a = 31.87(3), b = 7.705(9), c = 12.591(14) A°, b = 106.06(2)°, V = 2971(6) A°^3, Z = 8, Dc=1.530 g·cm^-1, F(000) = 1392, m = 0.266 mm^–1, S = 1.06, the final R = 0.070 and w R(I 〉 2s(I)) = 0.249. The crystal structure revealed that the carbonyl thiourea unit in the determined compound was mostly planar due in part to the formation of intramolecular N–H···O=C and C–H···S=C hydrogen bonds that form two S(6) rings. The intermolecular contacts of the crystal structure have been preformed based on the Hirshfeld surface and their associated 2D fingerprint plots. In the packing diagram of the synthesized compound, the C=S group formed two types of intermolecular hydrogen bonds by the H–N(C=O) group and the H–C of the phenyl ring, respectively, and they formed R2^2(8) and R2^2(14) ring motifs, respectively. The crystal packing form was also stabilized by the intermolecular hydrogen bonds C–H···O(1–x, y, 0.5–z) with the R2^2(10) ring motifs. In addition, supramolecular layers sustained by π-π stacking interactions(between the C(2)~C(7) rings with the C(10)~C(15) rings) are formed in the crystal structure of the title compound. The electronic and reactivity were assessed by the natural bond orbital(NBO) analysis in this study. 展开更多
关键词 crystal structure Hirshfeld surface analysis hydrogen-bonding interactions thiourea derivative
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Synthesis, Characterization and X-ray Structure of N-(4-bromobutanoyl-N'-(2-3-and 4-methylphenyl)thiourea 被引量:3
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作者 Hamza M Abosadiya Siti Aishah Hasbullah Bohari M Yamin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期379-385,共7页
N-4-(bromobutanoyl)-N'-(o-, m- and p-tolyl)thioureas 3a, 3b and 3c respectively, were synthesized by the reaction of 4-bromobutanoylisothiocyanate with p-, m- and o-toludine. The products were characterized by IR... N-4-(bromobutanoyl)-N'-(o-, m- and p-tolyl)thioureas 3a, 3b and 3c respectively, were synthesized by the reaction of 4-bromobutanoylisothiocyanate with p-, m- and o-toludine. The products were characterized by IR, and NMR spectroscopic techniques. The two carbonoylthiourea isomers N-(4-bromobutanoyl)-N'-(3-methylphenyl)thiourea (3b) and N-(4-bromobutanoyl)-N'-(4- methylphenyl)thiourea (3c) were obtained in crystalline form by recrystallization from DMSO. X- ray crystallographic studies showed that both compounds 3b and 3c crystallize in triclinic system with space group ofPi. The molecules adopt trans-cis configuration with respect to the positions of 4-bromobutanoyl and tolyl groups respectively, against the thiono C=S bond across their C-N bonds The configuration is attributed by the intrahydrogen bond between the carbonyl oxygen and amide hydrogen atoms. Both crystal structures are stabilized by N-H…S intermolecular hydrogen bonds to form dimers and arranged along the b axis. 展开更多
关键词 4-bromobutyryl chloride thiourea derivatives X-ray structural study
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Synthesis and Antibacterial Activity of Urea and Thiourea Derivatives of Anacardic Acid Mixture Isolated from A Natural Product Cashew Nut Shell Liquid (CNSL) 被引量:1
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作者 N. Subhakara Reddy A. Srinivas Rao +3 位作者 M. Adharvana Chari V. Ravi kumar V. Jyothy V. Himabindu 《International Journal of Organic Chemistry》 2012年第3期267-275,共9页
Synthesis and antibacterial activity of some novel urea and thiourea derivatives (8a - 8k, 9a - 9f) of anacardic acid prepared from commercially available anacardic acid which is obtained from natural product Cashew N... Synthesis and antibacterial activity of some novel urea and thiourea derivatives (8a - 8k, 9a - 9f) of anacardic acid prepared from commercially available anacardic acid which is obtained from natural product Cashew Nut Shell Liquid (CNSL). Compounds (8a - 8k, 9a - 9f) were tested for Gram positive and Gram negative bacterial cultures. Most of the compounds were showed active compared with standard drug ampicilline. 展开更多
关键词 SYNTHESIS UREA and thiourea Derivatives Anacardic Acid ANTI-BACTERIAL Activity
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Synthesis and Crystal Structure of a Copper(Ⅱ) Compound Constructed by N-(4,6-Dimethoxylpyrimidin)-N'-(ethoxycarbonyl)thiourea 被引量:1
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作者 傅丁薇 宋纪蓉 +3 位作者 任莹辉 严彪 吕兴强 胡怀明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期535-538,共4页
A copper(Ⅱ) complex Cu(L)2(NO3)2 constructed by the L (L = N-(4,6-dimethoxylpyrimidin)-N'-(ethoxycarbonyl)thiourea) ligand crystallizes in monoclinic, space group C2/c with a = 16.2416(16), b = 9.1385... A copper(Ⅱ) complex Cu(L)2(NO3)2 constructed by the L (L = N-(4,6-dimethoxylpyrimidin)-N'-(ethoxycarbonyl)thiourea) ligand crystallizes in monoclinic, space group C2/c with a = 16.2416(16), b = 9.1385(7), c = 22.0008(18) A, β = 108.077(2)°, V = 3104.3(5) A^3, Dc = 1.627 g/cm^3, Z = 4, C20H28CuN10O14S2, Mr = 760.18,μ(MoKa) = 0.920 mm^-1, F(000) = 1564, R = 0.0471 and wR = 0.1284 for 2239 observed reflections (I 〉 2σ(I)). X-ray diffraction shows the existence of weak complementary intramolecular N-H...O (DA) hydrogen bonds which further strengthen the coordination from the two L ligands with the Cu(Ⅱ) ion, intermolecular C-H...O hydrogen bonds and weak π...π stacking interactions, leading to the formation of a multi-dimensional supramolecular network. 展开更多
关键词 N-(4 6-dimethoxylpyrimidin)-N'-(ethoxyearbonyl)thiourea copper( complex suprarnolecular network
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