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Correlation Between Crystal Rotation and Redundant Shear Strain in Rolled Single Crystals: A Crystal Plasticity FE Analysis
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作者 Hui Wang Cheng Lu +3 位作者 Kiet Tieu Yu Liu Rui Wang Jintao Li 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第4期452-460,共9页
The correlation between crystal rotation and redundant shear strain in rolled single crystals was investigated by using the crystal plasticity finite element(CPFE) model in this paper. The deformation in aluminium sin... The correlation between crystal rotation and redundant shear strain in rolled single crystals was investigated by using the crystal plasticity finite element(CPFE) model in this paper. The deformation in aluminium single crystals of four representative orientations(rotated-Cube, Goss, Copper, and Brass) after rolling and plain strain compression was simulated, and the predictions have been validated by the experimental observations. In the rotated-Cube and Goss, the redundant shear strain and crystal rotation were in the same pattern, alternating along the thickness, while the relation between them was not obvious for the Copper and Brass due to their asymmetrical distributions of activated slip systems. The relations between slip system activation, crystal rotation, and shear strain were investigated based on the CPFE model, and the correlation between shear strain and crystal rotation has been built. 展开更多
关键词 CRYSTAL PLASTICITY finite element Single CRYSTAL CRYSTAL ROTATION Shear strain Orientation stability
A reduced-order method for parameter identification of a crystal plasticity model considering crystal symmetry
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作者 HAN ShiWei YANG XiaoGuang +1 位作者 SHI DuoQi HUANG Jia 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第3期373-387,共15页
The focus of this paper is to identify the material parameters of a crystal plasticity model for Ni-base single crystal superalloys.To facilitate the stepwise calibration of the multistage flow rules, further decoupli... The focus of this paper is to identify the material parameters of a crystal plasticity model for Ni-base single crystal superalloys.To facilitate the stepwise calibration of the multistage flow rules, further decoupling and simplification are implemented without compromising its simulating capability. Reduced-order kinematics in crystal plasticity, which only comprise scalar components instead of their original tensors, are derived by considering the crystal symmetry and uniaxial loading condition. The relationships between components in elastic and plastic deformation gradient are established by explicitly accounting the control quantities, which is overall load in stress-controlled creep tests or displacement of gauge section in strain-controlled experiments,respectively. In addition, their approximate forms are also given by neglecting both elastic changes in volume and section area. A new objective function based on the shortest distance was introduced to correlate data from the simulations and experiments, and an integrated optimization process without finite element computation was developed into a commercial software package.Parameters in the crystal plasticity model are successfully calibrated by the efficient reduced-order method from the experimental data in such a sequence as: elastic, plastic, primary stage and secondary to tertiary stages creep laws. The multistage weak coupling flow rules can significantly reduce the non-uniqueness of the optimal solution under the circumstance of excessive parameters but insufficient experimental data. Finally, the optimized results with the reduced-order method have been validated by the finite element method. 展开更多
关键词 reduced-order CRYSTAL PLASTICITY PARAMETER identification finite DEFORMATION single CRYSTAL CRYSTAL SYMMETRY
Scalable and ultrafast epitaxial growth of single-crystal graphene wafers for electrically tunable liquid-crystal microlens arrays
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作者 Bing Deng Zhaowei Xin +18 位作者 Ruiwen Xue Shishu Zhang Xiaozhi Xu Jing Gao Jilin Tang Yue Qi Yani Wang Yan Zhao Luzhao Sun Huihui Wang Kaihui Liu Mark H. Rummeli Lu-Tao Weng Zhengtang Luo Lianming Tong Xinyu Zhang Changsheng Xie Zhongfan Liu Hailin Peng 《科学通报:英文版》 SCIE EI CSCD 2019年第10期659-668,共10页
The scalable growth of wafer-sized single-crystal graphene in an energy-efficient manner and compatible with wafer process is critical for the killer applications of graphene in high-performance electronics and optoel... The scalable growth of wafer-sized single-crystal graphene in an energy-efficient manner and compatible with wafer process is critical for the killer applications of graphene in high-performance electronics and optoelectronics. Here, ultrafast epitaxial growth of single-crystal graphene wafers is realized on singlecrystal Cu90Ni10(1 1 1) thin films fabricated by a tailored two-step magnetron sputtering and recrystallization process. The minor nickel(Ni) content greatly enhances the catalytic activity of Cu, rendering the growth of a 4 in. single-crystal monolayer graphene wafer in 10 min on Cu90Ni10(1 1 1), 50 folds faster than graphene growth on Cu(1 1 1). Through the carbon isotope labeling experiments, graphene growth on Cu90Ni10(1 1 1) is proved to be exclusively surface-reaction dominated, which is ascribed to the Cu surface enrichment in the Cu Ni alloy, as indicated by element in-depth profile. One of the best benefits of our protocol is the compatibility with wafer process and excellent scalability. A pilot-scale chemical vapor deposition(CVD) system is designed and built for the mass production of single-crystal graphene wafers, with productivity of 25 pieces in one process cycle. Furthermore, we demonstrate the application of single-crystal graphene in electrically controlled liquid-crystal microlens arrays(LCMLA), which exhibit highly tunable focal lengths near 2 mm under small driving voltages. By integration of the graphene based LCMLA and a CMOS sensor, a prototype camera is proposed that is available for simultaneous light-field and light intensity imaging. The single-crystal graphene wafers could hold great promising for highperformance electronics and optoelectronics that are compatible with wafer process. 展开更多
关键词 GRAPHENE ULTRAFAST growth CuNi(1 1 1)thin film Single CRYSTAL wafer Liquid CRYSTAL MICROLENS arrays
Growth and fundamentals of bulk β-Ga2O3 single crystals 预览
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作者 H.F.Mohamed Changtai Xia +3 位作者 Qinglin Sai Huiyuan Cui Mingyan Pan Hongji Qi 《半导体学报:英文版》 EI CAS CSCD 2019年第1期7-15,共9页
The rapid development of bulk β-Ga2O3 crystals has attracted much attention to their use as ultra-wide bandgap materials for next-generation power devices owing to its large bandgap(~ 4.9 eV) and large breakdown elec... The rapid development of bulk β-Ga2O3 crystals has attracted much attention to their use as ultra-wide bandgap materials for next-generation power devices owing to its large bandgap(~ 4.9 eV) and large breakdown electric field of about8 MV/cm. Low cost and high quality of large β-Ga2O3 single-crystal substrates can be attained by melting growth techniques widely used in the industry. In this paper, we first present an overview of the properties of β-Ga2O3 crystals in bulk form. We then describe the various methods for producing bulk β-Ga2O3 crystals and their applications. Finally, we will present a future perspective of the research in the area in the area of single crystal growth. 展开更多
关键词 β-Ga2O3 CRYSTAL structure BULK CRYSTAL GROWTH APPLICATIONS
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反式聚异戊二烯结晶性能与分子模拟的研究进展 预览
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作者 吴剑铭 王小蕾 +3 位作者 汤琦 石雪龙 宗成中 王春芙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第7期167-174,共8页
概述了反式-1,4-聚异戊二烯(TPI)结晶行为的研究进展,如晶型的确定、晶型的形成条件、结晶的热力学和动力学过程、晶型之间的相互转化。其中重点介绍了TPI晶型的确定、α-晶型、β-晶型的反式-CTS-反式-CTS与反式-S^-TS分子链构象研究... 概述了反式-1,4-聚异戊二烯(TPI)结晶行为的研究进展,如晶型的确定、晶型的形成条件、结晶的热力学和动力学过程、晶型之间的相互转化。其中重点介绍了TPI晶型的确定、α-晶型、β-晶型的反式-CTS-反式-CTS与反式-S^-TS分子链构象研究进展。对近年来分子模拟技术在结晶方面的相关研究,如TPI晶型的构建、多相体系的结晶状态、凝聚态下晶体的相关性质、复杂体系下的结晶过程、动态环境下分子结晶的动态行为模拟研究进行了介绍,包括晶型的构建,如α-晶型、β-晶型的空间原子坐标与各向同性、各向异性之间的内在关系。 展开更多
关键词 反式-1 4-聚异戊二烯 结晶 晶型 构象 分子模拟
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Equivalent model of close-packed film cooling holes in nickel-based single crystal cooled blade based on crystallographic theory
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作者 Yamin ZHANG Zhixun WEN +1 位作者 Haiqing PEI Zhufeng YUE 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第4期839-850,共12页
The mechanical properties of nickel-based single crystal thin-walled plate with close-packed film cooling holes were studied based on the equivalent solid material concept. The effective plastic parameters inversion m... The mechanical properties of nickel-based single crystal thin-walled plate with close-packed film cooling holes were studied based on the equivalent solid material concept. The effective plastic parameters inversion method based on crystallographic theory were proposed. A simplification method for close-packed film cooling hole plates with square and triangular penetration patterns was presented. A large number of finite element analysis results covering different ligament efficiencies and penetration patterns were provided to verify the feasibility of the plastic equivalent principle and simplification method. The results show that the stress–strain curve and resolved shear stresses of simplification models are in consistence with the plate models with close-packed film cooling holes. The equivalent errors of yield strength are all within the error band and the values of equivalent errors are all less than 10%. In addition, the equivalent errors of the positions where maximum resolved shear stress occurs are all less than 15°, indicating the accuracy of plastic equivalent model and simplification method. 展开更多
关键词 Close-packed ?lm COOLING HOLES Crystallographic theory EQUIVALENT Simpli?cation Single crystal
High Sensitive Methane Sensor With Temperature Compensation Based on Selectively Liquid-Infiltrated Photonic Crystal Fibers
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作者 Hai LIU Haoran WANG +4 位作者 Wen ZHANG Cancan CHEN Qing WANG Yi DING Shoufeng TANG 《光子传感器:英文版》 EI CAS CSCD 2019年第3期213-222,共10页
A highly sensitive and temperature-compensated methane sensor based on a liquid-infiltrated photonic crystal fiber (PCF) is proposed. Two bigger holes near the core area are coated with a methane-sensitive compound fi... A highly sensitive and temperature-compensated methane sensor based on a liquid-infiltrated photonic crystal fiber (PCF) is proposed. Two bigger holes near the core area are coated with a methane-sensitive compound film, and specific cladding air holes are infiltrated into the liquid material to form new defective channels. The proposed sensor can achieve accurate measurement of methane concentration through temperature compensation. The sensitivity can reach to 20.07nm/% with a high linearity as the methane concentration is within the range of 0%-3.5% by volume. The proposed methane sensor can not only improve the measurement accuracy, but also reduce the metrical difficulty and simplify the process. 展开更多
关键词 PHOTONIC crystal fiber METHANE SENSOR directional RESONANCE coupling temperature COMPENSATION
异常大豆油浸腐乳中未知白色晶体的研究 预览
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作者 祝婷婷 苏沛 +3 位作者 曾裕 尹浩 程亚鹏 张飞鸿 《河南工业大学学报:自然科学版》 CAS 北大核心 2019年第3期67-70,117共5页
油浸腐乳是由豆腐坯经接种发酵、加盐腌制并添加油脂制备而成。一般腐乳中添加的油脂为大豆油,如果腐乳中出现不明结晶物则严重影响其品质。对异常油浸腐乳中未知白色晶体进行了分析,研究结晶形成原因。结果表明:该白色晶体在显微镜下... 油浸腐乳是由豆腐坯经接种发酵、加盐腌制并添加油脂制备而成。一般腐乳中添加的油脂为大豆油,如果腐乳中出现不明结晶物则严重影响其品质。对异常油浸腐乳中未知白色晶体进行了分析,研究结晶形成原因。结果表明:该白色晶体在显微镜下观察具有不规则形态,加热至40℃时可熔化。异常油浸腐乳中的油脂酸价达到正常商品一级大豆油酸价的240倍以上,为123.34mg/g。通过薄层色谱定性分析发现异常油浸腐乳中油脂的甘三酯含量很低,而游离脂肪酸含量和甘二酯及甘一酯含量很高;且腐乳中提取的固体脂的游离脂肪酸中的棕榈酸(C16∶0)和硬脂酸(C18∶0)含量远高于液体油,分别为24.72%和12.52%,远远大于国标。由此推断,该白色晶体为饱和游离脂肪酸聚合形成的结晶物,可能是腐乳中的脂肪酶(来自毛霉)水解油脂所致。 展开更多
关键词 油浸腐乳 晶体 固体脂 饱和游离脂肪酸 水解
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Synthesis, Structure and Luminescent Properties of Three 1D Chain Rare Earth Complexes 预览
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作者 陈砚美 李莲 +2 位作者 邱磊 李庆 张万举 《结构化学》 SCIE CAS CSCD 2019年第6期977-984,共8页
Three 1 D chain coordination polymers [Ln(pydc)2(H2 O)2]n·n Him(Ln = Dy(1), Gd(2), Sm(3), H2 pydc = pyridine-2,5-dicarboxylic acid, Im = imidazole), were solvothermally synthesized by the reaction of pyridine-2,5... Three 1 D chain coordination polymers [Ln(pydc)2(H2 O)2]n·n Him(Ln = Dy(1), Gd(2), Sm(3), H2 pydc = pyridine-2,5-dicarboxylic acid, Im = imidazole), were solvothermally synthesized by the reaction of pyridine-2,5-dicarboxylic acid(H2 pydc), Ln(Ⅲ) salts and imidazole. They have been characterized by X-ray single-crystal diffraction, IR spectra, TGA analysis and elemental analysis. Structural analyses revealed that complexes 1~3 have similar 1 D chain structures and belong to P1 space group. It is noteworthy that complexes 1~3 exhibited excellent thermal stability and no weightlessness below 117 ℃. Meanwhile, 1 and 3 show characteristic fluorescence of corresponding lanthanide metal ions in solid state at room temperature. 展开更多
关键词 RARE earth COMPLEXES LUMINESCENT property pyridine-2 5-dicarboxyllic acid crystal STRUCTURE
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Exploration of the structural and optical properties of a red-emitting phosphor K2TiF6:Mn4+
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作者 豆喜龙 邝小渝 +1 位作者 夏欣欣 巨濛 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期544-549,共6页
The exploration of the appropriate red phosphor with good luminescence properties is an important issue in the development of current white light-emitting diode(WLED) devices. Transition metal Mn-doped compounds are f... The exploration of the appropriate red phosphor with good luminescence properties is an important issue in the development of current white light-emitting diode(WLED) devices. Transition metal Mn-doped compounds are fascinating luminescent materials. Herein, we performed a systematic theoretical study of the microstructure and optical properties of K2TiF6:Mn4+ using the CALYPSO structure search method in combination with first-principles calculations. We uncovered a novel structure of K2TiF6:Mn4+ with space group P-3m1 symmetry, where the impurity Mn4+ ions are accurately located at the center of the MnF6 octahedra. Based on our developed complete energy matrix diagonalization(CEMD)method, we calculated transition lines for 2Eg →4A2,4A2→4T2, and4A2→T2at 642 nm, 471 nm, and 352 nm,respectively, which are in good agreement with the available experimental data. More remarkably, we also found another transition(4A2→2T2) that lies at 380 nm, which should be a promising candidate for laser action. 展开更多
关键词 crystal structures FIRST-PRINCIPLES CALCULATIONS K2TiF6
Synthesis, Crystal Structure and Antitumor Activities of 1,2,3,4-Tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) Derivatives 预览
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作者 李亦彪 杨志海 +2 位作者 王宗成 朱忠智 陈修文 《结构化学》 SCIE CAS CSCD 2019年第5期713-718,668共7页
A novel and efficient Ir-catalyzed 1,4-and 1,2-addition of diphenylphosphine oxide to quinolines was developed to obtain various 1,2,3,4-tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) derivatives. The struct... A novel and efficient Ir-catalyzed 1,4-and 1,2-addition of diphenylphosphine oxide to quinolines was developed to obtain various 1,2,3,4-tetrahydroquinoline-2,4-diyl(bisdiphenylphosphine oxide) derivatives. The structures of these derivatives were characterized by H-RMS and NMR analysis. X-ray crystallography showed that 3 a is in a monoclinic system, space group of P21/c with a = 13.0464(16), b = 12.6244(16), c = 20.210(3)A,β= 105.215(2)o, V =3211.9(7)A^3, Z = 4, F(000)= 1352,μ= 0.42 mm^–1, S = 1.07, the final R = 0.059 and wR = 0.195.The in vitro antitumor activities of target compounds were evaluated by MTT assay against human cancer K562, HL-60, HeLa and BGC-823. The target compounds demonstrated weak or moderate antitumor activity against these cell lines. 展开更多
关键词 1 2 3 4-tetrahydroquinoline-2 4-diyl(bisdiphenylphosphine oxide) DERIVATIVES SYNTHESIS crystal structure antitumor activity
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Syntheses, Structures and Herbicidal Activity of Bis(5-R-2-hydroxybenzylidene) Thiocarbohydrazide Monobutyltin Complexes [R: H(T1), Me(T2)] 预览
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作者 冯泳兰 张复兴 邝代治 《结构化学》 SCIE CAS CSCD 2019年第5期719-726,668共9页
The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes,[(5-R-2-hydroxy)ArCH=NNH]... The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes,[(5-R-2-hydroxy)ArCH=NNH]2 CS(n-BuSnCl)2, R = H(T1);R = Me(T2), based on the1,5-disubstituted thiocarbohydrazide were obtained by microwave-assisted solvothermal reaction of n-butyltintrichloride precursor with the ligands in methanol environments, which have been structurally characterized by elemental analysis, IR and(1 H, 13 C) NMR spectra. The crystals belong to monoclinic system, space groups C2/c(T1) and Pc(T2), respectively. The Sn atom is six-coordinated with distorted octahedral geometry by O, N and S atoms from ligand, C atom of butyl and two Cl atoms. In the crystal, complex T1 forms three-dimensional supramolecular assembly mediated by noncovalent interactions such as C–H···Cl and π-stacking interactions.Similarly, T2 forms an interesting two-dimensional supramolecular structure by noncovalent interactions(e.g. C–H×××Cl and N–H×××Cl) of one-dimensional band-like chain. These ligands and its butyltin complexes have growth effect on the target plants, such as Portulaca oleracea L.,Amaranthus spinosus L., Cassia tora L., Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee and Amaranthus tricolor L. The ligand L1 has a good inhibitory effect on the growth of Cassia tora L., and complex T2 has selective inhibition on the growth of Portulaca oleracea L. and Amaranthus tricolor L., which can be used as a candidate compound for Cassia tora L., Portulaca oleracea L.and Amaranthus tricolor L. herbicide. 展开更多
关键词 bis(2-hydroxybenzylidene)thiocarbohydrazide BUTYLTIN microwave SOLVOTHERMAL synthesis crystal structure herbicidal activity
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Synthesis, Crystal Structure and Herbicidal Activity of Methyl(E)-α-(Methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl)-pyridine-2-yl)phenoxy)methyl)benzeneacetate 预览
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作者 曹杨羊 王维伟 杜晓华 《结构化学》 SCIE CAS CSCD 2019年第7期1123-1128,共6页
The title compound methyl(E)-α-(methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl) pyridine-2-yl)phenoxy)methyl)benzeneacetate(C23 H18 ClF3 N2 O4) has been synthesized and structurally characterized by 1 H and 13 C NM... The title compound methyl(E)-α-(methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl) pyridine-2-yl)phenoxy)methyl)benzeneacetate(C23 H18 ClF3 N2 O4) has been synthesized and structurally characterized by 1 H and 13 C NMR, and HRMS. Its absolute molecular configuration was investigated by X-ray crystallography. The crystal crystallizes in monoclinic system, space group P21/c with a = 15.0928(7), b = 19.6070(10), c = 7.5535(5) A,β= 98.176(5)°, V = 2212.6(2)A3, Z =4, Dc = 1.438 g/cm^3, F(000)= 984,μ(Mo Kα)= 0.231 mm-1, the final R = 0.0619 and wR = 0.1681 with 4034 observed reflections with I > 2σ(I). The title compound has significant inhibitory rate against broadleaf weeds. They are all 100% under the dose of 37.5 g.a.i/ha, which was better than mesotrione. 展开更多
关键词 SYNTHESIS benzeneacetate crystal structure herbicidal activity
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Development of a particle swarm optimization based support vector regression model for titanium dioxide band gap characterization 预览
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作者 Taoreed O.Owolabi 《半导体学报:英文版》 EI CAS CSCD 2019年第2期49-55,共7页
Energy band gap of titanium dioxide(TiO2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such ... Energy band gap of titanium dioxide(TiO2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such as UV absorption, pigment,photo-catalysis, pollution control systems and solar cells among others. Substitution of impurities into crystal lattice structure is the most commonly used method of tuning the band gap of TiO2 for specific application and eventually leads to lattice distortion. This work utilizes the distortion in the lattice structure to estimate the band gap of doped TiO2, for the first time, through hybridization of a particle swarm optimization algorithm(PSO) with a support vector regression(SVR) algorithm for developing a PSO-SVR model. The precision and accuracy of the developed PSO-SVR model was further justified by applying the model for estimating the effect of cobalt-sulfur co-doping, nickel-iodine co-doping, tungsten and indium doping on the band gap of TiO2 and excellent agreement with the experimentally reported values was achieved. Practical implementation of the proposed PSO-SVR model would further widen the applications of the semiconductor and reduce the experimental stress involved in band gap determination of TiO2. 展开更多
关键词 band gap LATTICE DISTORTION crystal LATTICE parameters particle SWARM optimization support vector regression titanium dioxide
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Synthesis, Crystal Structure and Anion Recognition Property of a Flexible Urea-functionalized Receptor 预览
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作者 黄超 易瑞 +2 位作者 陈冬梅 朱必学 卢季红 《结构化学》 SCIE CAS CSCD 2019年第5期737-744,669共9页
A flexible urea-functionalized receptor bearing two p-nitrobenzene units was designed and synthesized from the reaction of precursors 4-nitrophenyl isocyanate and 1,2-bis(2?-aminophenoxy) benzene. The receptor was cha... A flexible urea-functionalized receptor bearing two p-nitrobenzene units was designed and synthesized from the reaction of precursors 4-nitrophenyl isocyanate and 1,2-bis(2?-aminophenoxy) benzene. The receptor was characterized by 1H NMR, MS, FTIR and elemental analysis, and the crystal structure of the receptor was determined by X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pca21 with a = 12.740(2), b =14.133(3), c = 15.842(3)A, V = 2852.4(9) A3, Z = 4, Mr = 620.57, Dc = 1.445 g/cm3, F(000)= 1288,= 0.0585 and wR = 0.1032 for 3177 observed reflections(Ⅰ> 2σ(Ⅰ)), and R = 0.1304 and wR =for all data. The results show that the receptor displays selective recognition ability for H2PO4– in DMSO with a series of anions using UV-Vis absorption spectra technique. Furthermore, the coordination reaction of the receptor with H2PO4– was investigated via UV-Vis spectra and 1 H NMR.The stoichiometric ratio and the association constant(Ka) of the coordination reaction were obtained as well. 展开更多
关键词 UREA RECEPTOR crystal structure RECOGNITION PROPERTY
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Synthesis, Crystal Structure and Spectroscopic Properties of Cyanide-bridged Complex [RuⅡ(ttpy)(CN)3MnⅢ(salen)] 预览
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作者 孙桂芳 栗佳琪 +4 位作者 余洪亮 于孟 彭佩 丁文文 王勇 《结构化学》 SCIE CAS CSCD 2019年第5期745-753,669共10页
Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-toly... Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine, salen = N,N?-ethylenebis-(salicylideneaminato)dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in orthorhombic Pbca space group and the asymmetric unit of 1 contains one[-NC-RuⅡ(ttpy)(CN)(m-CN)-Mn Ⅲ-(salen)-] molecule. In the structure of 1, each [Ru Ⅱ(ttpy)(CN)3]-connects two [MnⅢ(salen)]+ with two cyanide groups in a cis-conformation, and in turn each[MnⅢ(salen)]+ unit links two [RuⅡ(ttpy)(CN)3]-building blocks in a trans-conformation, resulting in a 1D [-NC-RuⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and luminescence spectroscopy of complex 1 have also been studied. 展开更多
关键词 CYANIDE-BRIDGED crystal structure Ru(Ⅱ) SPECTROSCOPIC properties Mn(Ⅲ)
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Syntheses, Crystal Structures and Hydrogen-bonding Motif of Two Glycoluril Derivatives 预览
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作者 刘雪梅 王东华 +1 位作者 宋新建 王军刚 《结构化学》 SCIE CAS CSCD 2019年第5期754-760,669共8页
The synthesis and aggregation behavior of two glycoluril derivatives were descrybed.The crystal of compound 1 belongs to the triclinic system,space group P1,with a=8.946(1),b=13.445(2),c=20.361(3)?,α=89.517(3),β=84.... The synthesis and aggregation behavior of two glycoluril derivatives were descrybed.The crystal of compound 1 belongs to the triclinic system,space group P1,with a=8.946(1),b=13.445(2),c=20.361(3)?,α=89.517(3),β=84.405(3),γ=86.325(3)°,Z=2,V=2432.1(6)?3,Dc=1.293 g·cm-3,C48H34N6O6·2DMSO,Mr=947.07,F(000)=992,μ=0.170 mm-1,the final R=0.1606 and wR=0.2410 for 4382 observed reflections(Ⅰ>2σ(Ⅰ)).The crystal of compound 2belongs to the monoclinic system,space group P21/c,with a=9.500(3),b=24.522(8),c=17.997(6)A,Z=2,V=4054(2)A^3,Dc=1.296 g·cm^-3,C48H34N6O6,Mr=790.81,F(000)=1648,μ=0.087mm-1,the final R=0.2146 and wR=0.2535 for 2878 observed reflections(Ⅰ>2σ(Ⅰ)).Unlike the highly conserved R22(8)hydrogen-bonding amide···amide homosynthon,the structural analysis indicated that compound 1 selected the C(20)hydrogen-bonding motif and 2 selected the R22(34)hydrogen-bonding motif,which revealed the competition from remote solvent molecule and the interference of the molecular hydrocarbon core in crystal packing.The supramolecular structure revealed molecule 1 is further linked into a one-dimensional chain and 2 into a two-dimensional interwoven plane by N–H···N hydrogen bonds. 展开更多
关键词 hydrogen bond GLYCOLURIL supramolecuclar SYNTHONS crystal engineering
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Synthesis, Structural Characterization and Magnetocaloric Effect of a Butterfly [Co^Ⅱ2Gd^Ⅲ2] Cluster 预览
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作者 刘通 黄渊梅 +2 位作者 邹华红 汪海玲 梁福沛 《结构化学》 SCIE CAS CSCD 2019年第7期1152-1158,共7页
2-(2,3-Dihydroxpropyliminomethyl)6-methoxyphenol(H3L), trimethylacetic acid(Hpiv), Gd(NO3)3·6 H2O and Co(NO3)2·6 H2O were reacted in Me OH to obtain a heterometallic tetranuclear cluster [Gd2Co2(L)2(μ3-OH)2... 2-(2,3-Dihydroxpropyliminomethyl)6-methoxyphenol(H3L), trimethylacetic acid(Hpiv), Gd(NO3)3·6 H2O and Co(NO3)2·6 H2O were reacted in Me OH to obtain a heterometallic tetranuclear cluster [Gd2Co2(L)2(μ3-OH)2(piv)6]·2 Hpiv·2 CH3OH(1). X-ray crystallographic analysis reveals that compound 1 was found to be a butterfly heterometallic tetranuclear cluster. The crystal(C64H108Co2Gd2N2O28, Mr = 1785.88) belongs to the triclinic crystal system, space group P1 with a =11.9798(6), b = 12.0877(5), c = 15.0367(7) A, α = 67.320(4)°, β = 81.583(4)°, γ = 75.201(4)°, V =1939.62(18) A3, Z = 1, T = 293.15 K, R = 0.048 and w R = 0.144 for 16299 observed reflections with I > 2σ(I). In magnetization study, heterometallic 1 exhibits magnetocaloric effect(MCE) of 14.75 J·kg-1·K-1 at 2 K for ΔH = 5 T, while it does not show non-linear response of the ac-susceptibilities. 展开更多
关键词 TETRANUCLEAR CLUSTER HETEROMETALLIC crystal structure MAGNETOCALORIC effect
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Synthesis, Crystal Structure, and Fluorescent and Thermal Stability Properties of Two New Cobalt(Ⅱ) Complexes with 2,2’-Bipy as Ligand 预览
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作者 李玉林 杨颖群 +1 位作者 毛芳芳 陈志敏 《结构化学》 SCIE CAS CSCD 2019年第5期769-776,670共9页
Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring... Two new cobalt(Ⅱ)complexes[Co2(2,2?-bipy)2(dpa)2(H2O)5]·4H2O(1)and Co(2,2?-bipy)3(SO4)]·7.5H2O(2)have been synthesized with diaphonic acid(H2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring cobalt(Ⅱ)ions are linked together by one bridging diaphonic acid group,forming an asymmetric dinuclear structure.1 crystallizes in triclinic,space group P1 with a=9.825(6),b=13.007(8),c=19.586(1)A,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,Mr=431.4,V=2406.5(3)A^3,Dc=1.48 g/cm^3,Z=2,μ(Mo Kα)=0.767 mm-1,F(000)=1112,the final R=0.0379 and wR=0.0862.The central cobalt(Ⅱ)ions in 1 and 2 are coordinated with six atoms,forming distorted octahedral coordination geometry.The fluorescence and thermal stability properties of 1 and 2 are also reported. 展开更多
关键词 cobalt(Ⅱ) complex crystal structure FLUORESCENCE thermal stability
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Reliability Design and Simulation of a Surface-Mount Temperature Compensation Crystal Oscillator
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作者 SUI Jianping CUI Wei +2 位作者 HASI Tuya ZHENG Wenqiang DUAN Youfeng 《中国航天:英文版》 2019年第2期24-31,共8页
This paper introduces the structure and principle of a surface-mount high-precision temperature compensation crystal oscillator,and specifically describes the reliability design of a quartz-crystal resonator used insi... This paper introduces the structure and principle of a surface-mount high-precision temperature compensation crystal oscillator,and specifically describes the reliability design of a quartz-crystal resonator used inside the surface-mount temperature compensation crystal oscillator,the reliability design of surface-mount ceramic base and the reliability design of hybrid micro-assembly.Finally,the thermal and mechanical simulation results and the experimental verification of this surface-mount temperature compensation crystal oscillator are provided,which prove that this crystal oscillator has high reliability. 展开更多
关键词 temperature COMPENSATION CRYSTAL OSCILLATOR (TCXO) high PRECISION reliability
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