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991.
Jin Young Lee Yong Han Lee Yong Gwan Byun 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):641-649
Abstract A new (E)-pyrene-1-carbaldehyde O-tert-butyldimethylsilyl oxime 3 was synthesized for the detection of chemical warfare nerve agents, O-isopropyl methylphosphonofluoridate (GB) and O-pinacolyl methylphosphonofluoridate (GD). 1H NMR spectrum showed that the tert-butyldimethylsilyl (TBDMS) group was deprotected using TBAF and the oximate supernucleophile was made. Upon addition of chemical warfare agents (GB and GD) (50 mol%), the reaction was completely finished within 5 min and also the color change of reaction mixture was observed under a hand-held UV lamp with the naked eye. 相似文献
992.
Gregory B. Kharas Xue Tian Whitney K. Castle Marie B. Cuison Maria R. Fath Bridget Nord 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):355-358
Electrophilic trisubstituted ethylene monomers, ring‐substituted 2‐cyano‐N,N‐dimethyl‐3‐phenyl‐2‐propenamides, RC6H4CH?C(CN)CON(CH3)2 (where R is 4‐(CH3)2N, 4‐CH3CO2, 4‐CH3CONH, 2‐CN, 3‐CN, 4‐CN, 4‐(C2H5)2N) were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and N,N‐dimethyl cyanoacetamide, and characterized by CHN elemental analysis, IR, 1H‐ and 13C‐NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, ABCN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C NMR, GPC, DSC, and TGA. High Tg of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 300–450°C range. 相似文献
993.
Novel Copolymers of Styrene and Alkoxy Ring‐Substituted 2‐Cyano‐N,N‐Dimethyl‐3‐Phenyl‐2‐Propenamides
Gregory B. Kharas Xue Tian Adam C. Hermsen Aditi S. Jani Larissa I. Kozij Emira Hadziahmetovic 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1485-1492
Electrophilic trisubstituted ethylene monomers, alkoxy ring‐substituted 2‐cyano‐N,N‐dimethyl‐3‐phenyl‐2‐propenamides, RC6H4CH?C(CN)CON(CH3)2 (where R is 2‐OCH3, 3‐OCH3, 4‐OCH3, 2‐OCH2CH3, 3‐OCH2CH3, 4‐OCH2CH2CH3, 4‐OCH2CH2CH2CH3), were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and N,N‐dimethyl cyanoacetamide, and characterized by CHN elemental analysis, IR, 1H‐ and 13C‐NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, ACBN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C NMR, GPC, DSC, and TGA. High Tg of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 300–450°C range. 相似文献
994.
Gregory B. Kharas Xue Tian Trang H. Huynh Thomas W. Lyons Lani A. Macartney Dylan Smith 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):469-473
Electrophilic trisubstituted ethylene monomers, halogen ring‐disubstituted 2‐cyano‐N,N‐dimethyl‐3‐phenyl‐2‐propenamides, RC6H3CH?C(CN)CON(CH3)2 (where R is 2,3‐dichloro, 2,4‐dichloro, 2,6‐dichloro, 3,4‐dichloro, 3,5‐dichloro, 2,3‐difluoro, 2,4‐difluoro, 2,6‐difluoro, 3,4‐difluoro, 3,5‐difluoro), were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and N,N‐dimethyl cyanoacetamide, and characterized by CHN elemental analysis, IR, 1H‐ and 13C‐NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, ABCN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C NMR, GPC, DSC, and TGA. High Tg of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 300–450°C range. 相似文献
995.
Xin Qi Sook Kyung Kim Su Jung Han Li Xu Ah Young Jee Ha Na Kim 《Supramolecular chemistry》2013,25(6):455-464
We report a small library of fluorophore-triazine tripod fluorescent system that can accommodate a combination of three different functional groups, such as fluorophore (BODIPY), ligand (or ligands) and auxiliary group. Syntheses, photophysical properties as well as binding properties towards metal ions of these BODIPY-triazine derivatives are described. 相似文献
996.
Meihua Han Jing Chen Yuqin Wang Shilin Chen Xiangtao Wang 《Journal of Analytical Chemistry》2013,68(8):730-735
A high-performance liquid chromatography — tandem mass spectrometry method was used in a comparative pharmacokinetic study on 20(S)-protopanaxadiol in its solution, pharmacosomes and hydroxy-propyl-β-cyclodextrin inclusion compound. The calibration linearity range was 2.5–5000 ng/mL and the limit of quantification was 2.5 ng/mL. The intra- and inter-assay coefficients of variation were less than 7% and the recoveries were 67.4, 63.3 and 69.6% at 5, 250 and 4500 ng/mL. In contrast to 20(S)-protopanaxadiol solution, its pharmacosomes and hydroxypropyl-β-cyclodextrin inclusion compound improved the oral bioavailability to different extent and meanwhile were much safer in clinical use. 相似文献
997.
Y. E. Du Z. Q. Xing Y. F. Liang Z. B. Han 《Russian Journal of Coordination Chemistry》2013,39(1):114-118
A new metal-organic coordination polymer [Zn(Pydc)(Dppz)] n (I) (H2Pydc = 2,6-pyridinedicarboxylic acid, Dppz = dipyrido[3,2-a:2′,3′-c]phenazine) was hydrothermally synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The X-ray diffraction analysis reveals that I crystallizes in the monoclinic system, space group P21/c. The Pydc2? ligands adopt O,N,O′-tridentate chelating and monodentate bridging coordination mode to link two adjacent Zn2+ ions to form a one-dimensional (1D) zigzag chain. The adjacent chains are further linked through hydrogen bonds and π-π stacking interactions, forming a three-dimensional (3D) supramolecular framework. The unit cell parameters for I: a = 7.332(3) Å, b = 36.023(9) Å, c = 7.8838(13) Å, β = 105.65(3)○, V = 2005.1(10) Å3, Z = 4. 相似文献
998.
The title cobalt(II) coordination polymer, [Co(Atibdc)(Dpa)] n (I) (H2Atibdc = 5-amino-2,4,6-triiodoisophthalic acid, Dpa = 2,2′-dipyridylanine), has been synthesized under solvothermal conditions and characterized by elemental analysis, IR, and X-ray crystallography structural analysis. Complex I exhibits a one-dimensional chain structure in which 5-amino-2,4,6-triiodoisophthalate as a bridging ligand interconnects adjacent two Co(II) centers to form a helical chain structure. The asymmetric unit includes one Co(II) center, one atibdc ligand, and one Dpa ligand. Each Co(II) center is five-coordinated and surrounded by two nitrogen atoms and three oxygen atoms from one Dpa ligand and two individual Atibdc ligands, leading to distorted trigonal bipyramid geometry. Adjacent chains are further linked through hydrogen bonds, C-H-π and π-π stacking interactions to form a three-dimensional supramolecular framework. 相似文献
999.
Xin Yu Cai-Rong Zhou Xue-Wei Han Guo-Peng Li 《Journal of Thermal Analysis and Calorimetry》2013,111(1):943-949
The combustion enthalpy of glyphosate was determined by XRY-1C oxygen-bomb calorimeter at a constant volume. The standard mole combustion enthalpy and the standard mole formation enthalpy have been calculated to be ?1702.19 and ?1478.36 kJ mol?1, respectively. For testing the reliability of instrument, glycine and naphthalene were used as reference materials by comparing the measured values with the literature values, the absolute error and relative error are 2.58 kJ mol?1 and 0.26 % for glycine, respectively, and these of naphthalene are 4.08 kJ mol?1 and 0.08 %, respectively. Moreover, the constant-pressure heat capacities c p of glyphosate were measured by differential scanning calorimetry in the temperature range 303.15–365.15 K, and the relationship between c p and temperature was established. These related studies can provide a thermodynamic basis for their further application. 相似文献
1000.
Tingting Li Guangwen Yang Jing Wang Yuanyuan Zhou Heyou Han 《Journal of Solid State Electrochemistry》2013,17(10):2651-2660
Recently, tremendous research efforts have been concentrated on developing high-performance electrode materials to meet the ever-increasing energy and power demands in supercapacitors. Herein, we presented a high-capacity supercapacitor material based on nitrogen-enriched hierarchical porous carbons (NHPCs) synthesized by the carbonization of melamine formaldehyde resins using eco-friendly and inexpensive nano-CaCO3 as template. The effects of carbonization temperature and template content on the porous structure and electrochemical characteristics were compared and discussed in detail. The prepared NHPCs possessed large surface area up to 834 m2 g?1 and high nitrogen content up to 20.94 wt %. As electrode material for supercapacitors, NHPCs exhibited superior electrochemical performances with high specific capacitance (190 F g?1 at 20 A g?1), outstanding rate capability (80 %), and excellent cycling stability (over 2,000 cycles at 5 A g?1) in 1 M sulfuric acid media. The excellent electrochemical performances are due to the synergic effects of unique hierarchical porous microstructure, abundant nitrogen and oxygen functionalities, as well as high degree of graphitization framework. 相似文献