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《农业系统科学与综合研究》 CSCD 2005年第3期195-195,共1页
金菊良、丁晶教授的专著《水资源系统工程》已由四川科学技术出版社出版。该书提出了由系统优化方法、建模方法、预测方法、模拟方法、评价方法和决策分析方法组成的现代应用系统工程新的理论体系。
关键词 金菊良 丁晶 《水资源系统工程》 四川科学技术出版社 书评
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Ni/Al_2O_3 catalysts derived from spinel NiAl_2O_4 for low-temperature hydrogenation of maleic anhydride to succinic anhydride 被引量:7
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作者 李杰 任远航 +1 位作者 岳斌 贺鹤勇 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1166-1173,共8页
Ni/Al2O3 catalysts were derived from spinel NiAl2O4 with different Ni content ((2.5, 5 and 7.5) wt%). The catalysts were obtained by H-2 reduction and were investigated for the low-temperature hydrogenation of maleic ... Ni/Al2O3 catalysts were derived from spinel NiAl2O4 with different Ni content ((2.5, 5 and 7.5) wt%). The catalysts were obtained by H-2 reduction and were investigated for the low-temperature hydrogenation of maleic anhydride (MA) to produce succinic anhydride (SA). The characterization results showed that Ni-0 active sites were mainly derived during the H2 reduction from spinel NiAl2O4 Among the catalysts studied, employing the optimum preparation and reaction conditions with Ni(5%)/Al2O3 yielded the highest catalytic performance. A near-100% conversion of MA and similar to 90% selectivity to SA were achieved at 120 degrees C and 0.5 MPa of H-2 with a weighted hourly space velocity (MA) of 2 h(-1). (C) 2017, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved. 展开更多
关键词 Maleic anhydride Succinic anhydride HYDROGENATION NICKEL SPINEL
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XRD Pattern of Liquid Crystal Monomer Acrylate That Conjugated with Cholesterol and p-Hydroxyphenyl-2-Methyl Butanoic
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作者 Afrlzal Muhammad Hikam +1 位作者 Bambang Soegiyono Asep Riswoko 《Journal of Chemistry and Chemical Engineering》 2012年第12期1051-1055,共5页
It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA (monomer cholesteryl acrylate) and monomer (S... It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA (monomer cholesteryl acrylate) and monomer (S)-(+)-4-(2-Methyl butanoat-l-butyloxy) phenyl 4-[1-(propenoyloxy) butyloxy] benzoate (MB). Two monomers were characterized by DSC (differential scanning calorimetry), POM (polarization optical microscopy) and XRD (X-ray diffraction). Mesophase temperatures of MA and MB are 81.28 ~C and 54.36~C, respectively. Textures analysis by POM shows that MA was oily streak and MB was schlieren. XRD pattern shows the strongest three peaks of MA at room temperature which are (20, deg): 2.7153, 5.2992 and 18.8500. The Strongest three peaks of MB at room temperature are (20, deg): 9.1726, 9.7707 and 12.5389. XRD pattern of MA and MB at mesophase and above mesophase temperature that each peaks disappear. 展开更多
关键词 Liquid crystal cholesteryl acrylate p-hydroxyphenyl-2-methyl butanoat.
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Synthesis and Crystal Structure of 1,4-Bis(2-hydroxymethylphenyl)-1,4-dioxabutane
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作者 许兴友 刘清亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期473-476,共4页
A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16... A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16H18O4 has been determined by single-crystal X-ray diffraction. The ligand crystallizes in the orthorhombic system, space group Pbcn with a = 13.777(1), b = 11.731(1), c = 9.076(8) ? V = 1466.8(2) ?, Mr = 274.30, Z = 4, F(000) = 548, Dc = 1.24 g/cm3, T = 293 K, m = 8.9 cm-1 and l = 0.71073 ? The structure was refined to R = 0.0324 and wR = 0.1025 for 1112 observed reflections with I > 2s(I). The two benzene rings are not on the same plane, and the dihedral angle between them is 60.6? The ligand has C2 symmetry axis which passes through the center of C(8)C(8a). The molecules are linked to each other by hydrogen bonding network to form supramolecular chain. The ligands connect to each other through the hydrogen bonds to form one-dimensional chains which further connect through the hydrogen bonds to form two- and three-dimensional structures. 展开更多
关键词 LIGAND SYNTHESIS crystal structure
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Two New Inclusion 1,4-Butylenediphosphonates with 3D Hydrogen-bonded Frameworks
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作者 傅瑞标 吴新涛 +2 位作者 胡胜民 杜文新 张建军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第8期855-861,共7页
Two new inclusion 1,4-butylenediphosphonates with three-dimensional hydrogen- bonded frameworks have been synthesized and determined by single-crystal X-ray diffraction. In compound 1, the two-dimensional cationic sub... Two new inclusion 1,4-butylenediphosphonates with three-dimensional hydrogen- bonded frameworks have been synthesized and determined by single-crystal X-ray diffraction. In compound 1, the two-dimensional cationic substructures interpenetrate into the anionic framework, and in compound 2, the cations are encapsulated in the three-dimensional framework. Crystal 1 (C14H24N2O8P2) belongs to triclinic, space group P?with a = 9.4645(2), b = 9.6490(2), c = 11.9479(3) ? = 79.7420(10), b = 73.5650(10), = 63.8420(10), V = 937.55(4) 3, Z = 2, Mr = 410.29, Dc = 1.453 g/cm3, m(MoKa) = 0.276 mm-1, F(000) = 432, the final R = 0.0465 and wR = 0.1304 for 3274 independent reflections. Crystal 2 (C18H26N2O10P2) is of monoclinic, space group P21/c with a = 9.7069(12), b = 16.227(2), c = 6.9339(9) ? b = 98.834(3), V = 1079.2(2) ?, Z = 2, Mr = 492.35, Dc = 1.515 g/cm3, m(MoKa) = 0.261 mm-1, F(000) = 516, the final R = 0.0611 and wR = 0.1162 for 1871 independent reflections. 展开更多
关键词 crystal structure 1 4-butylenediphosphonates hydrogen-bonded frameworks
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Synthesis and Crystal Structure of Potassium Crown Ether Tetrathiosquarate
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作者 Johannes Beck Younis O. Ben Amer 《Journal of Chemistry and Chemical Engineering》 2012年第5期470-474,共5页
Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis(potassium{18-crown-6})(3-cyclobutene-1,2-dithione-3,4-dith... Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis(potassium{18-crown-6})(3-cyclobutene-1,2-dithione-3,4-dithiolate) [K(C12H2406)]2(CnS4). The crystal structure determination (monoclinic, P 2t/n, a = 12.2095(8) A, b = 11.3263(8) A, c = 14.0552(7) A, fl = 101.032(3)~, Z = 2) shows the presence of C4S42 - ions with almost undistorted D4h symmetry having C-C bond lengths of 1.442(10) A and 1.478(8) A and C-S bond lengths of 1.651(8) A and 1.664(7) A. Since the K+ ions are shielded in a half-spherical way by the crown ether ligands, the crystal structures is built of centrosymmetric molecular entities [(18-crown-6)K(C4S4)K(18-crown-6)]. The K+ ions have eight of coordination number, C4S42- acts as a chelating and bridging ligand towards two K+ with K-S distances of 3.434(2) A and 3.380(2) A. 展开更多
关键词 Tetrathiosquarate crown ether potassium ion complex formation crystal structure.
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Miscibility, Crystallization, and Rheological Behavior of Solution Casting Poly(3-hydroxybutyrate)/poly(ethylene succinate) Blends Probed by Differential Scanning Calorimetry, Rheology, and Optical Microscope Techniques
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作者 孙伟华 乔晓平 +1 位作者 曹启坤 刘结平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期107-112,I0002,共7页
The miscibility and crystallization of solution casting biodegradable poly(3-hydroxybuty- rate)/poly(ethylene succinate) (PHB/PES) blends was investigated by differential scanning calorimetry, rheology, and opti... The miscibility and crystallization of solution casting biodegradable poly(3-hydroxybuty- rate)/poly(ethylene succinate) (PHB/PES) blends was investigated by differential scanning calorimetry, rheology, and optical microscopy. The blends showed two glass transition temperatures and a depression of melting temperature of PHB with compositions in phase diagram, which indicated that the blend was partially miscible. The morphology observation supported this result. It was found that the PHB and PES can crystallize simultaneously or upon stepwise depending on the crystallization temperatures and compositions. The spherulite growth rate of PHB increased with increasing of PES content. The influence of compositions on the spherulitic growth rate for the partially miscible polymer blends was discussed. 展开更多
关键词 MISCIBILITY Poly(3-hydroxybutyrate)/poly(ethylene succinate) blend Phase behavior CRYSTALLIZATION
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Synthesis and Crystal Structure of 1-(1'- t- Butyl-5'-methyl-4-pyrazolyl-carbonyl)- 3,5-dimethyl-1H-yl-pyrazole
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作者 文丽荣 付维军 +3 位作者 李明 赵桂龙 胡方中 杨华铮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第6期502-506,共5页
The crystal structure of 1-(1-t-butyl-5-methyl-4-pyrazolylcarbonyl)-3,5-dimeth- yl-1H-yl-pyrazole ([C14H20N4O]2, Mr = 520.68) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to tr... The crystal structure of 1-(1-t-butyl-5-methyl-4-pyrazolylcarbonyl)-3,5-dimeth- yl-1H-yl-pyrazole ([C14H20N4O]2, Mr = 520.68) has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic, space group P with a = 11.049(4), b = 11.313(4), c = 13.964(5) , ?= 69.085(6), b = 75.962(6), = 62.245(6), V = 1436.7(9) 3, Z = 2, Dc = 1.204 g/cm3, m = 0.079 mm-1, F(000) = 560, R = 0.0790 and wR = 0.1416 for 4729 unique reflections with 2635 observed ones (I > 2(I)). The results indicate that the pyrazole rings display aromaticity. The four pyrazole moieties are approximately coplanar in each case. The dihedral angles between planes 1 and 2, 3 and 4 are 40.99 and 10.77? respectively. 展开更多
关键词 bi-pyrazole crystal structure synthesis
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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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