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Application of Structured Health Education and Combined 5A Nursing Model in Self-control of Vulnerable Chronic Diseases: Take Coronary Heart Disease as an Example
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作者 Fan Li Shun Yuan +3 位作者 Chen Zhang Yan Li Qun Kong Qingjun Ding 《Journal of Clinical and Nursing Research》 2024年第6期206-213,共8页
Objective:To explore the intervention effect of the Structured Health Education course and 5A nursing model for self-control of elderly patients with coronary heart disease.Methods:Using the random sampling method,124... Objective:To explore the intervention effect of the Structured Health Education course and 5A nursing model for self-control of elderly patients with coronary heart disease.Methods:Using the random sampling method,124 elderly CAD patients admitted to the First Affiliated Hospital of Bengbu Medical University were randomly divided into an experimental group and a control group.The control group line routine health education,experimental group take structured health education combined with 5A nursing before and after the intervention using a coronary heart disease assessment questionnaire,coronary heart disease self-control scale evaluation of two groups of intervention,compare two groups before and after intervention blood pressure,blood sugar,body mass index,lipid index level and complications within 8 months after discharge.Results:After the course intervention,the disease cognition and self-behavior of the experimental group were higher than that of the control group,and the differences were statistically significant(all P<0.1).Conclusion:This course is suitable for elderly patients with coronary heart disease.The 5A model improves the cognitive and management ability of elderly patients to a certain extent,which is worthy of clinical application. 展开更多
关键词 Old age Coronary heart disease SELF-CONTROL structured health education 5A nursing
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TGF-β_(1)通过miR-21d-5p调控BMP7表达诱导肾小管上皮细胞增殖及迁移
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作者 陈香文 李惠 +14 位作者 廖湘平 刘黄华 张坚 黄教文 刘志超 张帆 龙圣海 龙英杰 邓华 张嘉 谢先达 许志敏 蒋伟 罗慧敏 陈喆 《中国中西医结合肾病杂志》 2024年第4期330-333,共4页
目的:探讨转化生长因子-β_(1)(TGF-β_(1))可能通过微小RNA-21d-5p(miR-21d-5p)对骨形态发生蛋白7(BMP7)的调控,从而对肾小管上皮细胞的增殖以及迁移的影响及可能机制。方法:观察TGF-β_(1)处理的肾小管上皮细胞HK-2并检测miR-21d-5p... 目的:探讨转化生长因子-β_(1)(TGF-β_(1))可能通过微小RNA-21d-5p(miR-21d-5p)对骨形态发生蛋白7(BMP7)的调控,从而对肾小管上皮细胞的增殖以及迁移的影响及可能机制。方法:观察TGF-β_(1)处理的肾小管上皮细胞HK-2并检测miR-21d-5p的表达,在HK-2细胞中分组转染miR-21d-5p或anti-miR-21d-5p,再使用TGF-β_(1)处理,观察过度表达或抑制表达miR-21d-5p对TGF-β_(1)诱导肾小管上皮细胞的细胞活性及迁移的影响。分析TGF-β_(1)、miR-21d-5p与BMP7的靶向关系。共转染miR-21d-5p和pcDNA3.1-BMP7,或anti-miR-21d-5p和si-BMP7,使用TGF-β_(1)处理,评估TGF-β_(1)、miR-21d-5p与BMP7的在肾小管上皮细胞的增殖以及迁移的相互关系。结果:TGF-β_(1)处理HK-2细胞后,miR-21d-5p表达和迁移细胞数量升高(P<0.05),P21和E-钙黏蛋白(E-cadherin)水平降低(P<0.05)。过度表达miR-21d-5p增加TGF-β_(1)诱导HK-2细胞增殖和迁移上调(P<0.05),降低P21和E-cadherin蛋白表达(P<0.05),过度表达BMP7可以逆转此过程。抑制miR-21d-5p降低TGF-β_(1)诱导HK-2细胞增殖和迁移细胞水平(P<0.05),显著升高P21和E-cadherin蛋白水平(P<0.05),被抑制表达的BMP7可以逆转此过程。结论:TGF-β_(1)可能通过miR-21d-5p靶向调控BMP7表达,从而诱导肾小管上皮细胞增殖及迁移,进一步影响肾脏纤维化进展。 展开更多
关键词 转化生长因子-β_(1) 微小RNA-21d-5p 7
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腐蚀产物中Zn_(5)(OH)_(8)Cl_(2)对纯Zn腐蚀行为的影响
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作者 杨元成 王友彬 +4 位作者 赵晋玮 周佳顺 冯济强 高峰 韦悦周 《表面技术》 EI CAS CSCD 北大核心 2024年第4期98-109,151,共13页
目的探究纯Zn腐蚀产物中碱式氯化锌(Zn_(5)(OH)_(8)Cl_(2),ZHC)对其腐蚀防护性能的影响以及腐蚀防护机理。方法通过原位生长法在纯Zn表面制备一层ZHC膜。通过X射线光电子能谱仪(XPS)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(ED... 目的探究纯Zn腐蚀产物中碱式氯化锌(Zn_(5)(OH)_(8)Cl_(2),ZHC)对其腐蚀防护性能的影响以及腐蚀防护机理。方法通过原位生长法在纯Zn表面制备一层ZHC膜。通过X射线光电子能谱仪(XPS)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS),分析了样品的物相组成和微观形貌。通过电化学阻抗谱(EIS)和动电位极化曲线(Tafel),评估了ZHC膜对纯Zn腐蚀防护性能的影响。结果纯Zn表面先形成了一层致密细小的ZHC纳米片,铺满整个纯Zn表面后,在第一层ZHC上形成第二层较大尺寸的ZHC纳米片。预制备的ZHC膜可以使纯Zn的腐蚀电流密度从78.23μA/cm^(2)降低到2.08μA/cm^(2),腐蚀电位从‒1.050V(vs.SCE)提升到‒0.998V(vs.SCE),并且随着ZHC制备时间的增加,阴极斜率(βc)逐渐增大,这表明ZHC可以有效阻碍电荷转移,抑制阴极的氧还原,减缓纯Zn的腐蚀速率,对Zn基体的腐蚀起到防护作用。在浸泡腐蚀过程中,ZHC可以抑制HZ的生成,减少絮状腐蚀产物的生成。在短期浸泡过程中,纯Zn的阻抗值随着预制备ZHC的增加而逐渐增大,这是因为生成的腐蚀产物填补ZHC纳米片的空隙,使腐蚀产物膜致密,ZHC膜对Zn基体能起到较好的防护作用。在长期浸泡过程中,ZHC/Zn的阻抗值下降,这是因为ZHC膜破裂,提供了新的腐蚀通道,导致ZHC膜对纯Zn的防护作用下降。结论ZHC膜可以减缓纯Zn的腐蚀速率。对比纯Zn和ZHC/Zn在浸泡过程中的腐蚀行为可知,在短期浸泡过程中,随着预制备ZHC的增加,对纯Zn的防护性能逐渐提高;在长期浸泡腐蚀过程中,ZHC膜对纯Zn腐蚀的防护作用逐渐下降。 展开更多
关键词 Zn_(5)(OH)_(8)Cl_(2) Zn
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六氟钽酸氨拓扑转变制备低深能级缺陷Ta_(3)N_(5)光阳极实现超低偏压光电化学分解水
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作者 徐伟 甄超 +7 位作者 朱华泽 姚婷婷 邱建航 梁艳 白朔 陈春林 成会明 刘岗 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期144-153,共10页
Ta_(3)N_(5)是一种具有2.1 eV直接带隙的n型半导体,其带隙跨越水的氧化还原电位.此外,Ta_(3)N_(5)的理论太阳能制氢效率(STH)高达15.9%,超过商业化应用的效率门槛(10%),是一种理想的光电化学分解水制氢光阳极材料.采用Ta2O5作为前驱体,... Ta_(3)N_(5)是一种具有2.1 eV直接带隙的n型半导体,其带隙跨越水的氧化还原电位.此外,Ta_(3)N_(5)的理论太阳能制氢效率(STH)高达15.9%,超过商业化应用的效率门槛(10%),是一种理想的光电化学分解水制氢光阳极材料.采用Ta2O5作为前驱体,在氨气气氛下高温氮化制备Ta_(3)N_(5)是一个由表及里的非均相氮化过程,该过程会产生大量的低价钽和氮空位等本征深能级缺陷,导致费米能级钉扎效应的产生,从而使得光生电压显著降低和光电流起始电位较高.因此,开发能够进行体相均相氮化的前驱体,以抑制Ta_(3)N_(5)深能级缺陷的产生,具有重要意义.本文采用气相溶剂热法,在钽箔上制备了一种六氟钽酸氨((NH_(4))_(2)Ta_(2)O_(3)F_(6))化合物,并以其多面体锥阵列薄膜作为前驱体,通过可控的氮化过程将前驱体结构拓扑转变为低深能级缺陷含量的Ta_(3)N_(5)多孔阵列薄膜.在高温氮化过程中,(NH_(4))_(2)Ta_(2)O_(3)F_(6)会释放含氮、氢和氟的气体小分子并形成贯穿体相的多孔通道,有利于氨气及氮化过程中产生的其他小分子物质的渗透,促进体相均匀氮化过程,避免生成大量的本征深能级缺陷.同时,(NH_(4))_(2)Ta_(2)O_(3)F_(6)中的高电负性氟离子可以减弱Ta–O键,进一步促进氮化反应.扫描电镜和透射电镜(TEM)结果表明,制备的(NH_(4))_(2)Ta_(2)O_(3)F_(6)是具有实心结构的多面体锥阵列薄膜,而拓扑转变所得的Ta_(3)N_(5)多面体锥薄膜具有多孔结构.X射线光电子能谱(XPS)、紫外-可见漫反射光谱和稳态/瞬态光电压谱表征结果表明,通过(NH_(4))_(2)Ta_(2)O_(3)F_(6)拓扑转变制备Ta_(3)N_(5)可有效抑制Ta_(3)N_(5)薄膜中深能级缺陷的形成.采用两种产氧反应助催化剂依次修饰后,XPS和TEM结果显示出助催化剂的双壳层结构与化学组成.光电化学分解水测试结果表明,所制得的Ta_(3)N_(5)光阳极在AM1.5G模拟太阳光的照射下,可展现出0.2 V_(RHE)(vs.RHE)的极低光电流起始电位,且在1.23 V_(RHE)时的光电流密度可达3.28 mA cm^(–2),经过连续5 h的稳定性测试,仍能保持初始值的85%.此外,稳定性测试前后助催化剂的XPS和TEM结果表明,Ta_(3)N_(5)光阳极光电流下降的原因可能是产氧助催化剂中硼物种的消耗.而通过减小(NH_(4))_(2)Ta_(2)O_(3)F_(6)多面体锥前驱体的尺寸,可以进一步减少Ta_(3)N_(5)薄膜中的本征深能级缺陷的含量,修饰助催化剂后可在0 V_(RHE)下展现出光电催化水氧化活性.综上所述,通过(NH_(4))_(2)Ta_(2)O_(3)F_(6)新型前驱体拓扑转变制备了低深能级缺陷含量的Ta_(3)N_(5)光阳极,表现出极低的光电流起始电位,为构建无偏压下自发全分解水的低深能级缺陷浓度的Ta_(3)N_(5)光电极提供了一种新途径,该方法也可拓展至其他过渡金属氮化物的可控制备与缺陷调控. 展开更多
关键词 (NH_(4))_(2)Ta_(2)O_(3)F_(6) 低缺陷Ta3N5
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Mo掺杂对笼目超导体CsV_(3)Sb_(5)结构和电磁性能的影响
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作者 李映 向峻杰 +1 位作者 杨帆 陈永亮 《广州化工》 CAS 2024年第8期115-118,141,共5页
新型笼目金属AV_(3)Sb_(5)(A=K, Rb, Cs)作为一个具有多种电子序耦合与竞争的平台,其丰富的物理特性备受关注。本文用新开发的以CsCl为辅助熔剂制备了不同掺Mo含量的Cs(V_(1-x)Mo_(x))3Sb5多晶样品,并通过对XRD数据进行Rietveld分析获... 新型笼目金属AV_(3)Sb_(5)(A=K, Rb, Cs)作为一个具有多种电子序耦合与竞争的平台,其丰富的物理特性备受关注。本文用新开发的以CsCl为辅助熔剂制备了不同掺Mo含量的Cs(V_(1-x)Mo_(x))3Sb5多晶样品,并通过对XRD数据进行Rietveld分析获得了其晶格结构信息,通过测量各样品的磁化强度及电阻率随温度变化关系,对其磁性和电输运性质进行了表征和分析。结果表明,随着Mo的掺入,母相CsV_(3)Sb_(5)的晶格常数a和晶胞体积略微增大,锑烯层中的Sb2原子会逐渐偏离笼目层。同时,体系的超导电性被抑制,而电荷密度波转变温度却增大,二者呈相互竞争关系。 展开更多
关键词 Cs(V_(1-x)Mo_(x))_(3)Sb_(5)
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Yb∶Ca_(3)(NbGa)_(5)O_(12)晶体的坩埚下降法生长及光学性能研究
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作者 赵涛 艾蕾 +3 位作者 梁团结 钱慧宇 孙志刚 潘建国 《人工晶体学报》 CAS 北大核心 2024年第4期620-626,共7页
使用坩埚下降法成功生长出了镱离子掺杂钙铌镓石榴石晶体(Yb∶Ca_(3)(NbGa)_(5)O_(12))。通过XRD测试分析了晶体的结构,该晶体为立方晶系,晶胞参数a=b=c=12.471。对该晶体进行了拉曼光谱、透过光谱、吸收和发射光谱、荧光寿命等测试,计... 使用坩埚下降法成功生长出了镱离子掺杂钙铌镓石榴石晶体(Yb∶Ca_(3)(NbGa)_(5)O_(12))。通过XRD测试分析了晶体的结构,该晶体为立方晶系,晶胞参数a=b=c=12.471。对该晶体进行了拉曼光谱、透过光谱、吸收和发射光谱、荧光寿命等测试,计算了该晶体的吸收截面、发射截面、增益截面等。研究了在空气中退火对该晶体吸收光谱、发射光谱、荧光寿命的影响,退火前在935 nm处吸收截面为1.82×10^(-20)cm^(2),退火后降低为1.40×10^(-20)cm^(2),退火前在1031 nm处的发射截面为0.56×10^(-20)cm^(2),退火后降低为0.40×10^(-20)cm^(2),退火前荧光衰减时间为1.42 ms,退火后为1.32 ms。结果表明,Yb∶Ca_(3)(NbGa)_(5)O_(12)单晶在空气中退火会对晶体的激光性能造成不利影响。 展开更多
关键词 Yb∶Ca_(3)(NbGa)_(5)O_(12)晶体 退
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Sm^(3+)掺杂Na_(5)Y(MoO_(4))_(4-y)(WO_(4))_(y)高热稳定性荧光粉的制备及发光性能研究
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作者 胡正开 杨伟斌 +3 位作者 熊飞兵 郭益升 白鑫 李明明 《人工晶体学报》 CAS 北大核心 2024年第6期1016-1025,共10页
本文采用高温固相法合成了一系列Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)(x=0~0.10,y=0~4)橙红色荧光粉。通过粉末衍射、透射电镜、常温/变温荧光发射谱、荧光激发谱、荧光动态衰减曲线和CIE色度坐标等光谱手段对荧光粉样品... 本文采用高温固相法合成了一系列Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)(x=0~0.10,y=0~4)橙红色荧光粉。通过粉末衍射、透射电镜、常温/变温荧光发射谱、荧光激发谱、荧光动态衰减曲线和CIE色度坐标等光谱手段对荧光粉样品的光谱性能进行了研究。粉末衍射结果表明,合成的样品相位与Na_(5)Y(MoO_(4))_(4)的标准相一致,Sm^(3+)掺杂与引入(WO_(4))2-均未改变材料的相结构。在波长为406 nm光源的激发下,Na_(5)Y0.92(MoO_(4))3WO_(4)∶0.08Sm^(3+)荧光粉在643 nm附近橙红色荧光发射强度最高,继续增加Sm^(3+)的掺杂浓度,存在荧光猝灭现象,浓度猝灭的主要原因归为电偶极-电偶极相互作用。研究发现,Na_(5)Y(MoO_(4))_(4)基质中掺杂Sm^(3+)会引起电负性改变和晶格畸变,在Na_(5)Y_(1-x)(MoO_(4))_(4)∶xSm^(3+)中引入(WO_(4))2-阴离子基团,可以弥补因掺杂Sm^(3+)出现的缺陷,改善Na_(5)Y(MoO_(4))_(4)∶xSm^(3+)荧光粉的发光性能。在300~440 K,样品具有优异的热稳定性,荧光发射强度均超过室温时的96%;其CIE色度坐标均位于橙红光区域。以上结果表明新型Na_(5)Y_(1-x)(MoO_(4))_(4-y)(WO_(4))y∶xSm^(3+)橙红色荧光粉在WLED应用上有潜在价值。 展开更多
关键词 Na_(5)Y(MoO_(4))_(4) Sm^(3%PLUS%) LED
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姬塬油田马家山地区长4+5_(1)亚段油藏特征及主控因素
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作者 沈明玲 冯小勇 +2 位作者 张志鹏 时保宏 崔郑曦 《重庆科技学院学报(自然科学版)》 CAS 2024年第1期7-14,共8页
为了加深对姬塬油田马家山地区长4+5_(1)亚段油藏特征及其主控因素的认识,从烃源岩构造、优势砂体及物性特征等方面对其作了对比分析。分析认为:研究区位于长7段烃源岩生烃中心,具有成藏的有利基础;叠置的优势砂体,促成了长7段烃源岩向... 为了加深对姬塬油田马家山地区长4+5_(1)亚段油藏特征及其主控因素的认识,从烃源岩构造、优势砂体及物性特征等方面对其作了对比分析。分析认为:研究区位于长7段烃源岩生烃中心,具有成藏的有利基础;叠置的优势砂体,促成了长7段烃源岩向长4+5_(1)亚段排出油气运移的主要通道;分流河道交汇处高渗砂体与近东西向排状鼻隆构造的匹配形成了石油聚集的有利场所;长4+5_(1)亚段油藏在多因素的共同控制下主要发育岩性油藏,其纵向上的砂体结构决定了石油富集于长4+5^(2)_(1)小层。 展开更多
关键词 长4+5_(1)亚段
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基于YOLOv5_4layers的PCB小目标缺陷识别方法
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作者 杨萍萍 白艳茹 《仪表技术与传感器》 CSCD 北大核心 2024年第3期75-79,共5页
针对PCB表面缺陷分辨率低、小目标性以及多样性等问题,提出了一种基于YOLOv5_4layers的PCB小目标缺陷识别方法。该方法在YOLOv5架构的基础上,通过新增采样层的方式添加小目标检测层,优化特征金字塔模型,提升小目标特征提取性能,实现小... 针对PCB表面缺陷分辨率低、小目标性以及多样性等问题,提出了一种基于YOLOv5_4layers的PCB小目标缺陷识别方法。该方法在YOLOv5架构的基础上,通过新增采样层的方式添加小目标检测层,优化特征金字塔模型,提升小目标特征提取性能,实现小目标缺陷识别。在调整合适的锚框规格后,改进后的模型在输入640像素×640像素图像时,相较原模型识别精确率提升了7.5%。在输入736像素×736像素图像时,识别精确率提升了1.3%,有效地提升了对PCB小目标缺陷的识别能力,对提高PCB制造过程的质量控制和产品可靠性具有实际意义。 展开更多
关键词 PCB YOLOv5_4layers
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Structure, Stability and Vibrational Spectra of LaC_5~n(n=-1,0,+1) Clusters
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作者 武志坚 孟庆波 张思远 《分子科学学报》 CAS CSCD 1998年第1期20-24,共5页
用密度泛含方法研究了LaC5n(n=-1,0,+1)分子簇的结构和稳定性及振动光谱,对这个六原子体系提出了三种可能构型,点群结构为C2v对称性.第一个构型为La接在弯曲的C5链上,第二个是La通过二个键与C5环相连... 用密度泛含方法研究了LaC5n(n=-1,0,+1)分子簇的结构和稳定性及振动光谱,对这个六原子体系提出了三种可能构型,点群结构为C2v对称性.第一个构型为La接在弯曲的C5链上,第二个是La通过二个键与C5环相连第三个是La通过一个键与C5环相连;结果表明,第一个构型即当La接在弯曲的C5链上时能量最低.振动光谱分析指出,当n=-1时,第二个构型为局域极小值;当n=+1时,第一个和第二个构型为局域极小值;对n=0,局域极小值没有找到. 展开更多
关键词 LaC5n Gausian92/dft
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Microstructure,Properties,and Grain Growth Kinetics of Mo-5Ta Refractory Sputtering Targets Prepared by SPS
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作者 LIU Dawei YANG Xiaolong +2 位作者 HUANG Lei PAN Yafei ZHANG Jiuxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1248-1254,共7页
Mo-5Ta targets were prepared by the spark plasma sintering(SPS)technology under the sintering temperatures of 1400-1600℃,the holding times of 0-20 min,and the axial pressure of 30 MPa.The microstructure,performance,a... Mo-5Ta targets were prepared by the spark plasma sintering(SPS)technology under the sintering temperatures of 1400-1600℃,the holding times of 0-20 min,and the axial pressure of 30 MPa.The microstructure,performance,and grain growth kinetics of Mo-5Ta sputtering targets were studied.With the increase of sintering temperatures and times,Ta can more dissolve in Mo and form a Mo(Ta)solid solution.The grain sizes of Mo-5Ta targets remain unchanged at low temperatures(1400-1500℃)while increasing significantly at high temperature(1600℃)with the extension of the holding time.In addition,the densities and Vickers hardness(HV_(0.5))first ascend and then decrease with sintering proceeding.The thermal conductivity is positively correlated with the grain size and density,as a result of their joint action.Based on the comprehensive analysis,the grain growth is dominated by the combination of boundary diffusion and volume diffusion.When n=2,the activation energies of grain growth under holding times of 5,10,20 min are calculated as 762.70,617.86,and 616.52 kJ/mol,respectively. 展开更多
关键词 SPS Mo-5Ta targets structure PROPERTIES grain growth kinetics
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Correlation between valence electronic structure and magnetic properties in RCo_5(R=rare earth) intermetallic compound 被引量:4
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作者 薛智琴 郭永权 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期165-171,共7页
The magnetisms of RCo5(R = rare earth) intermetallics are systematically studied with the empirical electron theory of solids and molecules(EET).The theoretical moments and Curie temperatures agree well with exper... The magnetisms of RCo5(R = rare earth) intermetallics are systematically studied with the empirical electron theory of solids and molecules(EET).The theoretical moments and Curie temperatures agree well with experimental ones.The calculated results show strong correlations between the valence electronic structure and the magnetic properties in RCo5 intermetallic compounds.The moments of RCo5 intermetallics originate mainly from the 3d electrons of Co atoms and 4f electrons of rare earth,and the s electrons also affect the magnetic moments by the hybridization of d and s electrons.It is found that moment of Co atom at 2c site is higher than that at 3g site due to the fact that the bonding effect between R and Co is associated with an electron transformation from 3d electrons into covalence electrons.In the heavy rare-earth-based RCo5 intermetallics,the contribution to magnetic moment originates from the 3d and 4f electrons.The covalence electrons and lattice electrons also affect the Curie temperature,which is proportional to the average moment along the various bonds. 展开更多
关键词 EET theory electronic structure Curie temperature RCo5 intermetallics
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Synthesis and Crystal Structure of a Co(Ⅱ) Complex with Taurine-5-methyl-2-hydroxyisophthalaldehyde Schiff Bases [Co(C_(13)H_(16)N_2O_7S_2)(H_2O)_3]_2·H_2O 被引量:2
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作者 QIN Xiu-Ying JIANG Yi-Min +1 位作者 ZHANG Shu-Hua MO Qian-Qun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期205-209,共5页
The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the ... The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds. 展开更多
关键词 cobalt complex taurine-5-methyl-2-hydroxyisophthalaldehydes crystal structure
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Synthesis and Crystal Structure of a Novel Ternary Borate, NaSrB_5O_9 被引量:3
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作者 陈学安 左建龙 +2 位作者 常新安 臧和贵 肖卫强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第9期1081-1086,共6页
A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, spa... A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, space group P21/c with a = 6.499(2), b = 13.979(3), c = 8.045(2)A, β = 106.92(2)°, V = 699.2(3)A^3, Z = 4, Mr = 308.66, Dc = 2.932 g/cm^3, μ = 7.804 mm^-1, F(000) = 584, R = 0.0264 and wR = 0.0621 for 2426 observed reflections and 146 variables. NaSrB5O9 is a layered compound containing double ring B5O11 building units composed of two BO4 tetrahedra and three BO3 triangles. Each B5O11 unit is connected to four other equivalent units through exocyclic oxygen atoms to form a two-dimensional ∞^2 [B5O9]^3- layer. Symmetry-center related layers are stacked along the b axis and held together by Na^+ and Sr^2+ cations via electrostatic interactions. 展开更多
关键词 NaSrB5O9 BORATE SYNTHESIS crystal structure
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Solvothermal Synthesis and Structure of the [Co(5-NH_2-bdc)(4,4'-dpdo)(H_2O)]_n Complex (4,4'-dpdo = 4,4'-Bipyridrl-N,N'-dioxide,5-NH_2-bdc = 5-Aminoisophthalic Acid) 被引量:1
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作者 张淑华 靳振江 +2 位作者 邹华红 钟凡 葛成敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1630-1634,共5页
The title compound [Co(5-NH2-bdc)(4,4'-dpdo)(H2O)]n 1 (5-NH2-bdc = 5-aminoiso- phthalic acid,4,4'-dpdo = 4,4'-bipyridrl-N,N'-dioxide) crystallizes in triclinic,space group P1 with a = 4.999(1),b = 10.072... The title compound [Co(5-NH2-bdc)(4,4'-dpdo)(H2O)]n 1 (5-NH2-bdc = 5-aminoiso- phthalic acid,4,4'-dpdo = 4,4'-bipyridrl-N,N'-dioxide) crystallizes in triclinic,space group P1 with a = 4.999(1),b = 10.072(2),c = 13.028(3) A,α = 107.72(3),β = 92.58(3),γ = 98.11(3)°,V = 615.9(3) A^3,F(000) = 356,Rint = 0.0186,Z = 2,R = 0.0333,wR = 0.0721,S = 1.032 and (Δ/σ)max = 0.001. In the molecule of 1,the Co(II) cation is coordinated by three O-atoms of two 5-NH2-bdc ligands,one N-atom of another 5-NH2-bdc ligand,one O-atom of 4,4'-dpdo and one terminal O-atom of water molecule. The molecules construct a 2-D network through bridging 5-NH2-bdc and 4,4'-dpdo ligands,and further form a 3-D network through N–H and O–H hydrogen bonds. The network topology of 1 can be simplified as a rare 2D (3,6)-connected (426381) net. 展开更多
关键词 cobalt crystal structure 4 4-dpdo 5-aminoisophthalic acid
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Synthesis and Crystal Structure of 3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)- pyrrol-2-yl)pentane·2CH_3OH 被引量:3
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作者 徐兰 刘尚远 尹振明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第4期613-617,共5页
3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group ... 3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group Pccn with a = 18.094(2), b = 11.6890(16), c = 13.3629(19) , V = 2826.3(7) 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F(000) = 1080 and μ(MoKα) = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ(I), and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds. 展开更多
关键词 3 3‘-bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane crystal structure hydrogen bonding
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Electronic structure and properties of LaNi_5 compound from first principles 被引量:2
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作者 WU Yeqiong YAN Mufu 《Rare Metals》 SCIE EI CAS CSCD 2010年第4期351-354,共4页
The energy, electronic structure, and magnetic and mechanical properties of LaNi5 compound have been studied by the first-principles method based on the density functional theory. The results show that the calculated ... The energy, electronic structure, and magnetic and mechanical properties of LaNi5 compound have been studied by the first-principles method based on the density functional theory. The results show that the calculated lattice parameters of LaNi5 compound are almost the same with the experimental ones, and the compound is easy to form and very stable. The bond between La and Nil atoms is an ionic bond, and electrostatic attraction effect exists between Ni atoms. The farther the distance between Ni atoms in the LaNi5 crystal cell is, the stronger the electrostatic attraction effect is. LaNi5 intermetallic compound is ductile and ferromagnetic. The calculated hardness value of LaNi5 compound is 7.04 GPa, and the calculated elastic properties are close to the experimental results. 展开更多
关键词 LANI5 mechancal properties first-pincioles electronic structure
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Synthesis and Crystal Structure of a 1D Coordination Polymer:{[Cu(HSSA)(py)_3]·H_2O}_n (H_3SSA =5-Sulfosalicylic Acid,py = Pyridine) 被引量:1
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作者 葛春华 张向东 +4 位作者 关磊 尹晶 王铁梅 赵阳 何翠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期1028-1032,共5页
The title compound [Cu(HSSA)(py)3H2O]n (H3SSA = 5-sulfosalicylic acid, py = pyridine) I has been synthesized and structurally determined by single-crystal X-ray diffraction. I was further characterized by elemen... The title compound [Cu(HSSA)(py)3H2O]n (H3SSA = 5-sulfosalicylic acid, py = pyridine) I has been synthesized and structurally determined by single-crystal X-ray diffraction. I was further characterized by elemental analyses, thermogravimetric analyses, IR and UV-visible spectroscopy. The crystal belongs to the monoclinic system, space group P21/c with a = 9.4564(10), b = 18.2679(19), c = 15.7284(12) A,β= 126.045(4)°, V= 2196.9(4)A^3, Z= 4, Dc = 1.618 g/cm^3, Mr = 535.02,μ = 1.141 mm^-1, F(000) = 1100, 2(MoKα) = 0.71073 A, the final R = 0.0429 and wR = 0.1044 for all observed reflections. In the structure, every two Cu(II) atoms are bridged by a bivalent 5-sulfosalicylic anion to form a 1D chain-like coordination polymer. Lattice waters between chains link them to form 2D layers which are further linked by C-H…O hydrogen bonds to form a three-dimensional supramolecular network. 展开更多
关键词 copperII complex 5-sulfosalicylic acid coordination polymer crystal structure
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Synthesis, Crystal Structure and Theoretical Calculation of [2-(2,6-Dioxacyclohexyl)-5-methoxylphenols]_2 被引量:1
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作者 段文增 冯帅 +1 位作者 孙斌 吴仁涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第10期1290-1295,共6页
The title compound [2-(2,6-dioxacyclohexyl)-5-methoxylphenols]2 was synthesized by the reaction of 2-hydroxyl-3-methoxylbenzaldehyde and 1,3-propanediol in the presence of DMF-DMS adduct and characterized by IR spec... The title compound [2-(2,6-dioxacyclohexyl)-5-methoxylphenols]2 was synthesized by the reaction of 2-hydroxyl-3-methoxylbenzaldehyde and 1,3-propanediol in the presence of DMF-DMS adduct and characterized by IR spectrum, UV-Vis spectrum and X-ray crystallography. The title compound belongs to monoclinic, space group P21 with a = 9.8967(10), b = 8.2240(9), c = 13.3654(14) A^°, β= 90.016(2)°, C11H14O4, Mr = 210.22, V = 1087.8(2)A^°3, Z = 4, Dc = 1.284 Mg/m^3, F(000) = 448,μ = 0.098 mm^-1, the final R = 0.0300 and wR = 0.0761 for 2070 observed reflections with I 〉 2σ(I). The molecules are connected via intermolecular O-H…O hydrogen bonds into a 2D network structure. Moreover, theoretical investigations of the title compound with HF/6-31G(d) method were performed, and its stability, frontier molecular orbital composition and Mulliken charge distribution were also discussed. The compound is a bis-molecule. The two molecules stay together and could not be separated. Two crystallographically independent molecules exist in an asymmetric unit. The bond lengths and bond angles of the two molecules are slightly different with each other. 展开更多
关键词 [2-2 6-dioxacyclohexyl)-5-methoxylphenols]2 crystal structure hydrogen bonds theoretical calculation
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Synthesis, Crystal Structure and Magnetic Properties of a One-dimensional Loop-like Iron(Ⅱ) Complex:[Fe(Haip)_2(H_2O)_2]_n (Haip = 5-Ammoniumisophthalato) 被引量:1
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作者 张来军 李燕红 +2 位作者 陈发云 吴辉勇 陈骁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期550-556,共7页
An iron(Ⅱ) coordination polymer, [Fe(Haip)2(H2O)2]n (1, Haip = 5-ammoniumiso- phthalato), has been hydro/solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, i... An iron(Ⅱ) coordination polymer, [Fe(Haip)2(H2O)2]n (1, Haip = 5-ammoniumiso- phthalato), has been hydro/solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectrum and magnetic measurement. Compound 1 crystalizes in monoclinic, space group P2/c with a = 6.9874(14), b = 9.960(2), c = 12.894(4) A, β = 117.47(2)°, Fe(C8H6NO4)2(H2O)2, Mr = 452.16, V= 796.2(3) A3, Z = 2, Dc = 1.886 g.cm-3, p = 1.017 mm-1, F(000) = 464.0, 2.71〈0〈28.42°, R = 0.0307, wR = 0.0840 and S = 1.005. Single-crystal X-ray diffraction analysis reveals that 1 features an infinite one-dimensional loop-like chain structure and Haip ligand in 1 is of zwitterionic form. Magnetic measurement results show the dominated ferromagnetic interactions among Fe11 atoms. 展开更多
关键词 iron complex crystal structure magnetic property loop-like chain 5-ammoniumisophthalato Haip
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