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Hydrothermal Synthesis, Crystal Structure and Thermal Property of a Coordination Polymer Constructed by Ce(Ⅲ) and Succinate Ions
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作者 ZHANG Zai-Chao ZHAO Pu-Su +4 位作者 QIN Yong-Qi ZHU Feng-Xia ZHU Chang-Lei HU Xin-Ming LI Rong-Qing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第3期376-383,共8页
A new three-dimensional coordination polymer [Ce_2(C_4H_4O_4)_3(H_2O)_2]_n·3.2 nH_2 O, constructed by Ce(Ⅲ) ion and succinate ion and lattice water molecules has been synthesized under hydrothermal conditions. I... A new three-dimensional coordination polymer [Ce_2(C_4H_4O_4)_3(H_2O)_2]_n·3.2 nH_2 O, constructed by Ce(Ⅲ) ion and succinate ion and lattice water molecules has been synthesized under hydrothermal conditions. It crystallizes in triclinic system, space group P1 with a = 7.8865(6), b = 12.0260(8), c = 12.2598(9) ?, α = 112.456(2)o, β = 90.046(2)o, γ = 100.423(2)o, Mr = 722.14, V = 1053.73(13) ?~3, Z = 2, Dc = 2.276 g/cm^3, μ = 4.35/mm, F(000) = 696, GOF = 1.029, R = 0.0203 and w R = 0.0570. The asymmetric unit contains two Ce^(3+) cations and both of them are nine-coordinated and their coordination geometries can be described as two distorted monocapped square antiprisms. In the title compound, a three-dimensional coordination network with one-dimensional hexagon honeycomb-like channels along the a axis is generated. TG measurement has been carried out, and its result analysis along with the powder XRD determination indicates the residue to be CeO_2. 展开更多
关键词 HYDROthermal synthesis crystal structure thermal property cerium(Ⅲ) complex
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Synthesis,Crystal Structure and Thermal Property of a 2D Brick Wall Framework Constructed from a New Mononuclear Complex
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作者 张云 张士真 +2 位作者 李建定 党娟 陶偌偈 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第9期1321-1326,共6页
One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n(H4L = 2-hydroxy-3-[(E)-({3-[(2-hydroxybenzoyl)amino]propyl}imino)methyl] benzoic acid) has been synthesized based on the... One new coordination polymer with the chemical formula [CoCu2L2·K2·1.5C2H5OH]n(H4L = 2-hydroxy-3-[(E)-({3-[(2-hydroxybenzoyl)amino]propyl}imino)methyl] benzoic acid) has been synthesized based on the slow diffusion method,and characterized by IR spectroscopy,thermalgravimetric and X-ray diffraction analysis.It crystallizes in the monoclinic system,space group P21/n with a = 11.98860(10),b = 24.4279(3),c = 14.9008(2) ,β = 104.7490(10)°,V = 4220.01(8) 3,Z = 2,Mr = 1009.94,Dc = 1.590 g/cm3,F(000) = 2056,μ(MoKα) = 1.649 mm-1,the final R = 0.0411 and wR = 0.1178 for 5920 observed reflections with I 2σ(I).The compound possesses a 2D brick wall structure constructed from trinuclear units. 展开更多
关键词 coordination polymer crystal structure brick wall thermal property
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Synthesis, Crystal Structure and Thermal Property of a Manganese(II) 4-Carboxyphenoxyacetate Complex
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作者 霍丽华 高山 +3 位作者 刘继伟 谷长生 赵辉 赵经贵 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期334-338,共5页
The manganese(II) complex, [Mn(phen)2(4-CPOA)(H2O)]?5H2O (4-CPOAH2 = 4- carboxyphenoxyacetic acid) has been synthesized and characterized by elemental analyses, IR, TG and single-crystal X-ray diffraction. The cryst... The manganese(II) complex, [Mn(phen)2(4-CPOA)(H2O)]?5H2O (4-CPOAH2 = 4- carboxyphenoxyacetic acid) has been synthesized and characterized by elemental analyses, IR, TG and single-crystal X-ray diffraction. The crystal is of monoclinic, space group C2/c, with a = 27.471(3), b = 18.490(4), c = 14.507(3) ?, β = 115.13(3)o, V = 6671(3) ?3, Z = 8, Mr = 717.58, Dc= 1.429 g/cm3, μ = 0.462 mm–1, F(000) = 2984, the final R = 0.0535 and wR = 0.1200 for 5413 observed reflections with I > 2σ(I). The Mn(II) atom is coordinated by one O atom of 4-carboxy- phenoxyacetate, four N atoms of two 1,10-phenanthroline and one water molecule, residing in a distorted octahedral environment. A supramolecular network structure is formed by hydrogen bonds and π-π stacking interactions. 展开更多
关键词 manganese (II) carboxylate complex crystal structure thermal property
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Effect of long-term thermal exposure on microstructure and creep properties of DD5 single crystal superalloy 被引量:3
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作者 Xu-dong Wang Zhong Yang +1 位作者 Qiang Gao Li-rong Liu 《China Foundry》 SCIE CAS 2021年第3期185-191,共7页
The effect of thermal exposure on the microstructure and creep properties of the Ni-based single crystal superalloy in different test conditions was studied.Long-term exposure was performed at 1,000 ℃ and 1,100 ℃ fo... The effect of thermal exposure on the microstructure and creep properties of the Ni-based single crystal superalloy in different test conditions was studied.Long-term exposure was performed at 1,000 ℃ and 1,100 ℃ for 500 h prior to the creep tests.The creep lifetime is found to be improved after the long-term exposure at 1,000 ℃ for 500 h as a result of the formation of secondary M_(23)C_(6) in the interdendritic region.The coarsening of γ’ precipitates accompanied by the formation of TCP phase lead to the degradation of alloy,which is responsible for the reduction of the creep lifetime of Ni-base single crystal superalloy after long-term exposure at 1,100 ℃ for 500 h.The creep lifetime of 1,000 oC thermally exposed sample under the conditions of 1,093 ℃/137 MPa is lower than that of heat-treated state.Thermal exposure at 1,100 ℃ for 500 h causes the creep lifetime to drop drastically. 展开更多
关键词 long-term thermal exposure MICROSTRUCTURE creep properties Ni-based single crystal superalloy M_(23)C_(6)carbide
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Synthesis, Crystal Structure and Thermal Properties of N,N′-Bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) Ethylene Diamine 被引量:2
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作者 任元林 程博闻 +3 位作者 张金树 臧洪俊 康卫民 丁长坤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期70-74,共5页
The title compound N,N'-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylene diamine (DPTDEDA, C12H26N2O4P2S2) was synthesized by the reaction of neopentyl glycol, phosphorus thio-chloride and 1,2-ethylene... The title compound N,N'-bis(5,5-dimethyl-2-phospha-2-thio-1,3-dioxan-2-yl) ethylene diamine (DPTDEDA, C12H26N2O4P2S2) was synthesized by the reaction of neopentyl glycol, phosphorus thio-chloride and 1,2-ethylenediamine, and characterized by elemental analysis, IR and ^1H NMR spectra. Its crystal structure was determined by single-crystal X-ray diffraction analysis and the thermal property was analyzed by TG analysis. The crystal structure belongs to monoclinic, space group P21/c, with a = 14.557(16), b = 11.299(12), c = 12.163(13)A,β = 98.707(19)^o, Dc = 1.305 g/cm^3, Z = 4, γ = 0.71073A,μ(MoKa) = 0.447 mm^-1, Mr = 388.41, V = 1977(4)A3, F(000) = 824, S = 1.107, the final R = 0.0478 and wR = 0.0810 for 1738 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the crystal structure is centrosymmetrically distributed through 1,2-ethylenediamine to join two distorted six-membered rings. The weak N-H…S interactions are observed and link the molecules into sheets. TG analysis shows that the title compound has good thermal stability and char-forming capability, which are required for an excellent intumescent fire retardant. 展开更多
关键词 N N'-bis(5 5-dimethyl-2-phospha-2-thio-1 3-dioxan-2-yl) ethylene diamine phos-phorus thiochloride crystal structure thermal property intumescent fire retardant
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Crystal Structure and Thermal Stability Properties of a New 1D Chain Cu(Ⅱ)Coordination Polymer with2,3-Pyridinedicarboxylic Acid as the Ligand 被引量:1
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作者 李薇 李昶红 +2 位作者 李衡锋 许金生 李励 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1567-1571,共5页
A new 1D chain copper coordination polymer [CuE(H2L)2(C10HsN2)(HEO)2]n'3n(H20) with 2,3-pyridinedi carboxylic acid (H2L) and 2,2'-bipyridine (2,2'-bipy) as ligands has been synthesized in the mixed etha... A new 1D chain copper coordination polymer [CuE(H2L)2(C10HsN2)(HEO)2]n'3n(H20) with 2,3-pyridinedi carboxylic acid (H2L) and 2,2'-bipyridine (2,2'-bipy) as ligands has been synthesized in the mixed ethanol and water solvents. Crystal data for this complex are as follows: monoclinic, space group P2Jc, a = 7.7713(7), b = 27.478(3), c = 13.2621(13)/1,, fl = 100.6940(10), V= 2782.8(5) A3, Dc = 1.722 g/cm3, Z = 4, p = 1.61 mm-1, F(000) = 1472, the final R = 0.0363 and wR = 0.0933. In the crystal structure, the whole molecule consists of two cooper ions, two H2L, one 2,2"-bipy molecule and six water molecules. Each central copper ion is coordinated with three oxygen atoms from two H2L and one water molecule, two nitrogen atoms from one 2,2'-bipy molecule and two H2L, giving a distorted tetragonal pyramidal geometry. Thermal stability properties of the complex were investigated. 展开更多
关键词 copper(II) coordination polymer crystal structure thermal stability properties
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Amylose Content,Morphology,Crystal Structure,and Thermal Properties of Starch Grains in Main and Ratoon Rice Crops 被引量:1
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作者 Na Kuang Huabin Zheng +3 位作者 Qiyuan Tang Yuanwei Chen Xiaomin Wang Youyi Luo 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第4期1119-1130,共12页
Rice ratooning,or the production of a second rice crop from stubble after the harvest of the main crop,is considered to be a green and resource-efficient rice production system.The present study was conducted to exami... Rice ratooning,or the production of a second rice crop from stubble after the harvest of the main crop,is considered to be a green and resource-efficient rice production system.The present study was conducted to examine variance in amylose content(AC),grain morphology,crystal structure,and thermal properties of starch between main-and ratoon-season rice of seven varieties.Ratoon-season rice grains had higher ACs and significantly lower transition gelatinization temperatures(To,Tp,and Tc)than did main-season rice grains.The relative crystallinity and lamellar peak intensity of ratoon-season rice starch were 7.89%and 20.38%lower,respectively,than those of main-season rice starch.In addition,smaller granules with smoother surfaces and lower thermal parameters were observed in the starch of ratoon-season rice.The relative crystallinity and lamellar peak intensity of starch correlated negatively with the AC and positively with transition gelatinization temperatures.These results suggest that the superior cooking quality of ratoon-season rice is attributable to the moderate increase of grain AC,which reduces the relative crystallinity,weakens the crystal structure,and lead to a decrease in the gelatinization temperature. 展开更多
关键词 Ratooning rice STARCH amylose content crystal structure thermal property
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Mechanical, Thermal and Crystallization Properties of Polypropylene (PP) Reinforced Composites with High Density Polyethylene (HDPE) as Matrix 被引量:1
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作者 Harekrushna Sutar Prakash Chandra Sahoo +4 位作者 Prateekshya Suman Sahu Surajabala Sahoo Rabiranjan Murmu Sumit Swain Subash Chandra Mishra 《Materials Sciences and Applications》 2018年第5期502-515,共14页
Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile... Our work aims to evaluate a complete outlook of virgin high density polyethylene (HDPE) and polypropylene (PP) polyblends. Virgin PP of 20, 30 and 50 weight% is compounded with virgin HDPE. The properties like tensile strength, flexural strength, Izod impact strength are examined. Scanning electron microscopy (SEM) and polarised light microscopy (PLM) are used to observe the surface and crystal morphology. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) tests verify the non compatibility of both polymers. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques are used to study the thermal behaviour of composites. The results manifest co-occurring spherulites for polyblends;indicating the composite to be a physical blend of continuous and dispersed phases, but on the other hand PP improves the tensile and flexural properties of HDPE. 展开更多
关键词 High Density Poly Ethylene (HDPE) POLYPROPYLENE (PP) Polyblends MECHANICAL thermal crystalLIZATION Properties
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Crystallization Behavior and Thermal Properties of PP/MgAl LDH Nanocomposites Prepared in Non-polar Solution
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作者 CUI Zhe ZHANG Guo-ying QU Bao-jun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期152-156,共5页
Polypropylene(PP)/MgAl layered double hydroxide(MgAl LDH) nanocomposites were synthesized by refluxing PP and dodecyl sulfate-intercalated MgAI LDH[MgAI(DS)] in non-polar xylene. Their structure, thermal and cry... Polypropylene(PP)/MgAl layered double hydroxide(MgAl LDH) nanocomposites were synthesized by refluxing PP and dodecyl sulfate-intercalated MgAI LDH[MgAI(DS)] in non-polar xylene. Their structure, thermal and crystallization properties were studied via X-ray diffraction(XRD), transmission electron microscopy(TEM), thermogravimetric analysis(TGA), differential scanning calorimetry(DSC), and polarized light microscopy(PLM). The nanoscaled dispersion of MgAI(DS) nanolayeres in the PP matrix was verified by the disappearance of the d(003) XRD diffraction peak of MgAI(DS) and observation of TEM image. The DSC data show that the SDS/LDH inorganic components negatively affect the crystallization properties of PP and decrease the size of PP sphcrulites because the inorganic components act as additional nuclei. The PP/MgA1 LDH nanocomposites have a faster charring progress in a temperature range of 250--430 ℃ and a better thermal stability above 320℃ than pure PP. 展开更多
关键词 Layered doubled hydroxide POLYPROPYLENE NANOCOMPOSITE thermal property crystallization behavior
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Hydrothermal Synthesis, Crystal Structure and Photoluminescent Property of a Novel Complex [Zn(OHCT)(1,2-BDC)]_n
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作者 李传碧 杨宇 +5 位作者 张首才 闫丽 李晶 孙丽娟 李文成 王家军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1233-1238,共6页
A novel ligand 11-oxa-4,5,9,10,12,13-hexaaza-cyclopenta [b] triphenylene (OHCT) and its coordination polymer [Zn(OHCT)(1,2-BDC)]n 1 (1,2-BDC = 1,2-benzenedicarboxylate) were synthesized and characterized. Crys... A novel ligand 11-oxa-4,5,9,10,12,13-hexaaza-cyclopenta [b] triphenylene (OHCT) and its coordination polymer [Zn(OHCT)(1,2-BDC)]n 1 (1,2-BDC = 1,2-benzenedicarboxylate) were synthesized and characterized. Crystallographic data for OHCT: C14H6N6O5, Mr = 274.25, monoclinic, space group P21/c, a = 10.755(3), b = 11.710(4), c = 9.516(3) , β = 108.457(4)o, V = 1136.9(6) 3, Dc = 1.602 g/cm3, μ(MoKα) = 0.111 mm-1, F(000) = 560, Z = 4, the final R = 0.1534 and wR = 0.39709. Crystallographic data for 1: C22H10ZnN6O5, Mr = 503.73, triclinic, space group P , a = 6.1411(5), b = 10.9111(9), c = 14.1925(1) , α = 89.1830(1), β = 79.3030(1), γ = 84.6350(1)o, V = 930.36(1) 3, Dc = 1.798 g/cm3, μ(MoKα) = 1.376 mm-1, F(000) = 508, Z = 2, the final R = 0.0323 and wR = 0.0789. 1 has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR spectrum, thermal analysis, fluorescence spectrum and single-crystal X-ray diffraction. In complex 1, the zinc atom is five-coordinated with three carboxylate oxygen atoms from three different 1,2-BDC ligands and two nitrogen atoms from one OHCT ligand, showing a distorted trigonal bipyramidal configuration. 展开更多
关键词 zinc(Ⅱ) complex crystal structure FLUORESCENCE thermal property
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Syntheses,Crystal Structures and Thermal Properties of Two Dicadmiun(II) Complexes Cd_2L_2X_2(HL=N-(3-Methoxylsalicylidene)-3-dimethylaminopropylamine,X = Cl(1),NCS(2))
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作者 林鸿 黄娟兰 冯云龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期718-722,共5页
Two Cd(Ⅱ) complexes, Cd2L2Cl2 (1) and Cd2L2(NCS)2 (2) (HL = N-(3-methoxylsalicylidene)-3-dimethylaminopropylamine) were synthesized and determined by EA, IR, TG and single-crystal X-ray diffraction. The c... Two Cd(Ⅱ) complexes, Cd2L2Cl2 (1) and Cd2L2(NCS)2 (2) (HL = N-(3-methoxylsalicylidene)-3-dimethylaminopropylamine) were synthesized and determined by EA, IR, TG and single-crystal X-ray diffraction. The crystallographic data are as follows: monoclinic, space group P21/n, a = 9.2710(9), b = 18.0069(18), c = 18.5562(19) A^°, β= 99.741(4)°, V = 3053.1(5), Z = 4,μ = 1.605, F(000) = 1536, R = 0.0264 and wR = 0.0699 for 1; orthorhombic, space group Pca21, a = 16.196(3), b = 11.506(2), c = 36.126(7) A^°, V = 6732(2), Z = 8,μ = 1.428, F(000) = 3264, R = 0.0376 and wR = 0.0877 for 2. There are two geometrically different octahedral Cd(Ⅱ) atoms, with N4O2 and O4Cl2 donor sets for 1 while N4O2 and N2O4 for 2. In the dinuclear Cd(Ⅱ) centers, the Cd(Ⅱ) atoms are held together by two deprotonted phenolate oxygen atoms from tetradentate L^- ligands. The thermal gravity data show two step decompositions with the residues of CdO for two complexes. 展开更多
关键词 crystal structures Cd(Ⅱ) complex Schiff base thermal property
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Synthesis, Crystal Structure and Thermal Property of Dimethyl Phenanthrene-9,10-dicarboxylate
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作者 LUO Zai-Gang LIU Qian-Nan +1 位作者 LI Rui XU Xue-Mei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第5期908-912,共5页
The target compound(C18H14O4)was synthesized and structurally determined by single-crystal X-ray diffraction.The crystal is of monoclinic system,space group P21/n with a=7.9383(6),b=19.5083(13),c=9.4189(7)?,β=98.981(... The target compound(C18H14O4)was synthesized and structurally determined by single-crystal X-ray diffraction.The crystal is of monoclinic system,space group P21/n with a=7.9383(6),b=19.5083(13),c=9.4189(7)?,β=98.981(2)°,C18H14O4,Mr=294.29,Dc=1.357 g/cm^3,V=1440.75(18)?3,Z=4,F(000)=616,μ(MoKa)=0.096 mm-1,T=293(2)K,3320 independent reflections with 1845 observed ones(I>2σ(I)),R=0.0529 and wR=0.1082 with GOF=1.015(R=0.1202 and wR=0.1278 for all data).The phenanthrene skeleton is coplanar.The overall crystal packing revealed that it has reverse staggered parallel and stratified arrangement.And a one-dimensional interaction model was formed by two kinds ofπ-πinteractions between the two adjacent molecules at upper and lower levels.The decomposition mechanism of compound 3 is complex. 展开更多
关键词 PHENANTHRENE SYNTHESIS crystal structure thermal property
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Synthesis, Crystal Structure and Thermal Stability Properties of the Supramolecular Complex [Co(phen)_3][(C_6H_5)_2C(OH)COO]_2·7H_2O
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作者 许金生 袁亚莉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第10期1325-1328,共4页
One new cobalt complex [Co(phen)3][(C6Hs)2C(OH)COO]2·7H2O with benzeneacetic acid (BAA), 1,10-phenanthroline and cobaltous perchlorate has been synthesized by means of solvent method. It crystallizes in t... One new cobalt complex [Co(phen)3][(C6Hs)2C(OH)COO]2·7H2O with benzeneacetic acid (BAA), 1,10-phenanthroline and cobaltous perchlorate has been synthesized by means of solvent method. It crystallizes in the triclinic system, space group P^-1, with a = 1.14181(13), b = 1.64417(18), c = 1.65342(18) nm, α = 74.2830(10), β= 84.4490(10), γ = 74.9430(10)°, V = 2.8842(6) nm^3, Dc = 1.359 g/cm^3, Z = 2, F(000) = 1234, R = 0.0621 and wR = 0.1673. The crystal structure shows that the cobalt ion is coordinated with six nitrogen atoms from three 1,10-phenanthroline molecules, giving a distorted octahedral coordination geometry. There are a lot of hydrogen bonds in the complex, from which a two-dimensional network is constructed. The result of TG analysis shows that the title complex is stable below 130.0 ℃. 展开更多
关键词 cobalt(Ⅱ) complex crystal structure thermal stability properties
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Crystal Structure and Thermal Property of 4-(3-Chlorophenyl)-3-isopropyl-1-methyl-3,4-dihydroquinolin-2(1H)-one
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作者 LI Hui-Juan LUO Zai-Gang WANG Xiu-Xiu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第5期913-917,共5页
The target compound(C19H20ClNO)was structurally determined by single-crystal X-ray diffraction.The crystal is in monoclinic system,space group P21/n with a=9.2365(2),b=12.1241(3),c=14.9960(4)?,β=106.589(3)°,C19H... The target compound(C19H20ClNO)was structurally determined by single-crystal X-ray diffraction.The crystal is in monoclinic system,space group P21/n with a=9.2365(2),b=12.1241(3),c=14.9960(4)?,β=106.589(3)°,C19H20ClNO,Mr=313.81,Dc=1.295 g/cm^3,V=1609.42(7)?3,Z=4,F(000)=664,μ(MoKa)=2.097 mm-1,T=200(10)K,2813 independent reflections with 2533 observed ones(I>2σ(I)),R=0.0389 and wR=0.1057 with GOF=1.043(R=0.0423 and wR=0.1083 for all data).The 3,4-dihydroquinolin-2(1 H)-one moiety maintains thermodynamically stable trans configuration.The decomposition mechanism of compound 3 is complex by thermal analysis. 展开更多
关键词 3 4-dihydroquinolin-2(1H)-one crystal structure thermal property
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THERMAL PROPERTY, MISCIBILITY AND CRYSTALLIZATION BEHAVIOR OF POLY(3-HYDROXYBUTYRATE-co-3-YDROXYHEXANOATE) AND POLY(BUTYLENE SUCCINATE-ADIPATE) (PHBHHX/PBSA) BLENDS
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作者 WANG Shufang GUO Tianying +3 位作者 TAO Jian ZHENG Chenggang ZHANG Banghua SONG Cunjiang 《Chinese Journal of Reactive Polymers》 2005年第1期1-7,共7页
Blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(butylene succinate-adipate) (PBSA), both biodegradable semicrystalline polyesters, were prepared with the ratio of PHBHHx/PBSA ranging from 80/... Blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(butylene succinate-adipate) (PBSA), both biodegradable semicrystalline polyesters, were prepared with the ratio of PHBHHx/PBSA ranging from 80/20 to 20/80 by melt mixing method. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), dynamic mechanical thermal analysis (DMA), polarizing optical microscopy (POM) and wide angle X-ray diffractometer (WAXD) were used to study the miscibility and crystallization behavior of PHBHHx/PBSA blends. Experimental results indicate that PHBHHx is immiscible with PBSA as shown by the almost unchanged glass transition temperature and the biphasic melt. 展开更多
关键词 Poly(3-hydroxybutyrate-co-hydroxyhexanoate)/poly(butylenes succinate-adipate) blends thermal property MISCIBILITY crystallization.
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Two Novel Nitrogen-rich Energetic Coordination Compounds M_2(DAT)_5(H_2O)_3(TNR)_2(M = Zn and Co):Synthesis,Characterization,Thermal Properties and Sensitivity 被引量:5
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作者 梁彦会 张建国 +3 位作者 崔燕 张同来 周遵宁 杨利 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期327-338,共12页
Two novel energetic coordination compounds Zn2(DAT)5(H2O)3(TNR)2 and Co2(DAT)5(H2O)3(TNR)2 were synthesized and their structures were characterized by elemental analysis and FT-IR spectroscopy.The crystal ... Two novel energetic coordination compounds Zn2(DAT)5(H2O)3(TNR)2 and Co2(DAT)5(H2O)3(TNR)2 were synthesized and their structures were characterized by elemental analysis and FT-IR spectroscopy.The crystal structures were determined by single-crystal X-ray diffraction.The results reveal that the compounds have similar molecular structures and the crystals belong to the triclinic system,space group P with a = 11.491(3),b = 13.564(3),c = 15.496(3) ,V = 2180.4(8) 3,C17H28 Zn2N36O19,Mr = 1203.02 g·mol-1,Dc = 1.832 g·cm-3,μ(MoKα) = 1.221 mm-1,F(000) = 1223,Z = 2,R = 0.0596 and wR = 0.1514 for 11289 observed reflections(I 〉 2σ(I)) for Zn2(DAT)5(H2O)3(TNR)2 and a = 11.5291(13),b = 13.4894(15),c = 15.4852(17) ,V = 2164.8(4) 3,C17H28Co2N36O19,Mr = 1190.14 g·mol-1,Dc = 1.826 g·cm-3,μ(MoKα) = 0.888 mm-1,F(000) = 1211,Z = 2,R = 0.0576 and wR = 0.1431 for 11218 observed reflections(I 〉 2σ(I)) for Co2(DAT)5(H2O)3(TNR)2,respectively.The thermal decomposition characteristics of the com-pounds were investigated using differential scanning calorimetry and thermal gravimetry-diffediffer-rential thermal gravimetry.The results of thermal decomposition processes were similar for the two compounds.Both undergo four-step decomposition after the loss of coordinated H2O molecules.The final solid residues for the two DAT complexes were the corresponding metal oxides.The kinetic parameter of the first exothermic process of the compounds was studied by applying the Kissinger and Ozawa-Doyle methods.The thermodynamic parameters of the activation could be calculated.Sensitivity tests revealed that Co2(DAT)5(H2O)3(TNR)2 was more sensitive than Zn2(DAT)5(H2O)3(TNR)2. 展开更多
关键词 1 5-diaminotetrazole energetic coordination compound crystal structure thermal decomposition sensitivity properties
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Structure and Thermal Properties of Transition Metal Imidazole Chloride 被引量:4
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作者 建方方 仝玉萍 +2 位作者 肖海连 汪庆祥 焦奎 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第9期979-984,共6页
The X-ray single-crystal structure analyses have been determined for two metal imidazole chlorides: [Fe(Im)6]Cl24H2O 1 and [CuCl(Im)4]Cl 2 (Im = imidazole). The red crystal of compound 1 is of triclinic, space group P... The X-ray single-crystal structure analyses have been determined for two metal imidazole chlorides: [Fe(Im)6]Cl24H2O 1 and [CuCl(Im)4]Cl 2 (Im = imidazole). The red crystal of compound 1 is of triclinic, space group Pi with Mr = 607.31 (C18H32Cl2FeN12O4), a = 8.797(2), b = 9.068(2), c = 10.581(2) ? a = 75.35(3), ?= 83.20(3), ? = 61.85(3)o, V = 720.0(2) 3, Z = 1, Dc = 1.401 g/cm3, F(000) = 316, = 0.755 mm-1, R = 0.0353 and wR = 0.1227. The blue crystal of compound 2 belongs to monoclinic, space group P21/c with Mr = 406.77 (C12H16Cl2CuN8), a = 13.909(3), b = 8.8933(18), c = 15.086(7) ? ?= 118.32(2), V = 1642.7(9) 3, Z = 4, Dc = 1.645 g/cm3, F(000) = 828, = 1.666 mm-1, R = 0.0609 and wR = 0.1726. In solid state, both 1 and 2 form three-dimensional hydrogen bond networks to stabilize the structures which were also characterized by TG and elemental analyses. The thermal gravity (TG) data indicate that the residues are Fe and Cu for 1 and 2, respectively. 展开更多
关键词 imidazole ligand crystal structure chloride compound thermal property
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Influence of temperature on the properties of one-dimensional piezoelectric phononic crystals 被引量:3
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作者 Ahmed Nagaty Ahmed Mehaney Arafa H Aly 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期342-345,共4页
The current study investigates the influence of temperature on a one-dimensional piezoelectric phononic crystal using tunable resonant frequencies. Analytical and numerical examples are introduced to emphasize the inf... The current study investigates the influence of temperature on a one-dimensional piezoelectric phononic crystal using tunable resonant frequencies. Analytical and numerical examples are introduced to emphasize the influence of temperature on the piezoelectric phononic crystals. It was observed that the transmission spectrum of a one-dimensional phononic crystal containing a piezoelectric material(0.7 PMN-0.3 PT) can be changed drastically by an increase in temperature.The resonant peak can be shifted toward high or low frequencies by an increase or decrease in temperature, respectively.Therefore, we deduced that temperature can exhibit a large tuning in the phononic band gaps and in the local resonant frequencies depending on the presence of a piezoelectric material. Such result can enhance the harvesting energy from piezoelectric materials, especially those that are confined in a phononic crystal. 展开更多
关键词 phononic crystals resonant modes piezoelectric material thermal properties and temperature
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Synthesis and Fluorescent, Magnetic and Thermal Stability Properties of a New Europium(Ⅲ) Complex Eu2(C15H11O3)6(C12H8N2)2 被引量:2
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作者 LI Jiao-Di WU Zhao-Zhao +3 位作者 SUN Yue YANG Ying YU Jiang-Xi YANG Ying-Qun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第11期1928-1933,共6页
A new europium(Ⅲ) complex Eu2(C15H11O3)6(C12H8N2)2 has been synthesized with 2-(4-Methylbenzoyl)benzoic acid and 1,10-phenanthroline as ligands. Crystal data for the complex are as follows: monoclinic, space grou... A new europium(Ⅲ) complex Eu2(C15H11O3)6(C12H8N2)2 has been synthesized with 2-(4-Methylbenzoyl)benzoic acid and 1,10-phenanthroline as ligands. Crystal data for the complex are as follows: monoclinic, space group P21/n, a = 15.1238(5), b = 13.5928(4), c = 22.9840(7) ?, β = 104.132(3)o, V = 4582.0(2) ?3, Dc = 1.522 g/cm3, Z = 4, μ(Mo Kα) = 1.433 mm-1, F(000) = 2128, the final R = 0.0447 and wR = 0.0826. The Eu(Ⅲ) ion is coordinated by eight atoms to give a distorted square antiprism coordination geometry. The complex shows two intense fluorescence emission bands arising from the transitions of Eu3+: 5 D0 → 7 F1(594 nm) and 5 D0 → 7 F2(617 nm). The complex is an antiferromagnetism system in the range of 150~300 K. Also reported in the paper is the thermal stability property of the title complex. 展开更多
关键词 europium(Ⅲ)complex crystal structure fluorescence MAGNETIC and thermal stability properties
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Syntheses, Crystal Structures, and Properties of Two New Lanthanide Coordination Polymers Constructed from Benzimidazole-5,6-dicarboxylic Acid 被引量:1
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作者 WANG Yong-Li WEI Zhen +5 位作者 MAO Wei-Xi ZHOU Song-Jia GENG Kang-Shua DOU Yun-Peng KANG Yan-Fei LIAO Bo 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期1029-1037,共9页
Two lanthanide coordination polymers, {[Ln(Hbidc)(bidc)(H2 O)3]·3 H2 O}n(H3 bidc = benzimidazole-5,6-dicarboxylic acid, Ln = Eu(1), Sm(2)) have been hydrothermally synthesized. Both compounds are isos... Two lanthanide coordination polymers, {[Ln(Hbidc)(bidc)(H2 O)3]·3 H2 O}n(H3 bidc = benzimidazole-5,6-dicarboxylic acid, Ln = Eu(1), Sm(2)) have been hydrothermally synthesized. Both compounds are isostructure and crystallize in the P21/c space group of monoclinic system. Complex 1: a = 11.087(6), b = 8.972(5), c = 23.064(13) ?, b = 95.027(5)o, V = 2285.4(2) ?3, Z = 4, Mr = 669.35, Dc = 1.945 g/cm3, F(000) = 1328, S = 1.044, μ = 2.827 mm-1, R = 0.0393 and wR = 0.0801 for 3458 observed reflections(I > 2s(I)). Complex 2: a = 11.087(6), b = 8.972(5), c = 23.064(13) ?, b = 95.027(5)°, V = 2285.4(2) ?3, Z = 4, Mr = 667.74, Dc = 1.941 g/cm3, F(000) = 1324, S = 1.071, μ = 2.652 mm-1, R = 0.0329 and wR = 0.0809 for 3744 observed reflections(I > 2s(I)). Complexes 1 and 2 have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric analyses(TGA). The single-crystal X-ray diffraction analysis reveals that complexes 1 and 2 are the isostructural 1 D zigzag chain structures, which are further extended into a 3 D supramolecular structure through hydrogen bonds and p···p stacking interactions. Furthermore, the thermal stability, UV-vis absorption spectra and fluorescent properties of complexes 1 and 2 have been investigated and discussed in detail. 展开更多
关键词 benzimidazole-5 6-dicarboxylic acid COORDINATION polymer crystal structure thermal stability FLUORESCENCE properties
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