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A new simple and rapid electrochemical method for the determination of hydroxyl radical generated by Fenton reaction and its application 总被引:3,自引:0,他引:3
A simple and rapid electrochemical method to detect the hydroxyl radical is described. This method employed the reaction between.OH and dimethyl sulfoxide (DMSO) to generate quantitatively formaldehyde, which then reacted with hydrazine hydrochloride at pH 6.2. The product showed a second-order derivative cathodic wave with the peak potential of -1.08 V( vsSCE) by single sweep oscillopolarography. The electrochemical behavior of the product was investigated by single sweep oscillopolarography and cyclic voltammetry. The experimental conditions for the measurement were optimized and the scavenging activity of some flavonoids on hydroxyl radicals was studied. 相似文献
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Tao Liu Yong-Gang Wei Qi-Hua Wu Qing-Xiang Guo 《Research on Chemical Intermediates》2005,31(9):833-844
A series of adamantanamine-(OCH2CH2)n-phenothiazine (n = 0, 1, 2, 3) electron donors was synthesized. Photoinduced electron transfer was observed in the supramolecular complex
of the phenothiazine derivatives with p-nitrobenzoyl-β-cyclodextrin (NBCD) through binding of the adamantyl group by the NBCD cavity, which is stabilized clearly via hydrophobic interactions in aqueous solution. Detailed Stern–Volmer constants were measured and they were partitioned into
dynamic Stern–Volmer quenching constants and static binding constants. The results revealed an efficient electron transfer
process inside the supramolecular systems compared to that controlled by diffusion. This observation also indicates that the
chain length will influence the electron transfer efficiency of a supramolecular donor–acceptor system. 相似文献
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ZHAO Qi-Huaa MA Yong-Pingb WANG Qing-Huab FANG Rui-Binb a 《结构化学》2002,21(5):513-516
1 INTRODUCTION Cadmium (Ⅱ) complexes have been exten- sively studied from both chemical and structural views, mainly due to the capability of cadmium (Ⅱ) (shared by most d10 metal ions) to adopt different modes of coordination determined by the consideration of size, as well as electrostatic and covalent bonding forces[1]. And the field of coordination polymers has witnessed tremendous growth over the last decade[2]. Many coordination polymeric networks have been shown to posses intere… 相似文献
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通过水热合成法,合成了4个配位聚合物:[Mn(H2O)(PTZDA)(BDC)]n(1)、[Co(H2O)(PTZDA)(BDC)]n(2)、[Zn(H2O)(PTZDA)(BDC)]n(3)、[Cd(H2O)(PTZDA)(BDC)]n(4)(PTZDA=2,4-二氨基-6-(2′-吡啶)-均三嗪,H2BDC=对苯二甲酸),并分别用X射线单晶衍射、元素分析、红外光谱、差热分析和X-射线粉末衍射表征了这4个配合物。晶体结构分析表明,在配合物1~4中,配体PTZDA与中心金属离子螯合配位,金属离子通过配体BDC2-连结成一维链状结构,一维链之间通过氢键作用连接成三维超分子结构。磁性和荧光分析表明,配合物1和2具有非常弱的反铁磁作用;配合物3和4的荧光均为配体发光。 相似文献
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Two coordination polymers (CPs), namely, [Zn(BPDC)(3-bpdb)0.5(H2O)2]n ( 1 ), and [Ni(BPDC)(3-bpdb)(H2O)2]n ( 2 ) (where H2BPDC = 4,4'-biphenyldicarboxylic acid, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene) have been solvothermally synthesized and characterized by single-crystal X-ray diffraction, IR, elemental analyses, PXRD, and SEM. CP 1 possesses a 2D 3-connected hcb net, and weak hydrogen bonding and π ··· π stacking contacts further link the 2D networks to form 3D supramolecular structure. The structure of 2 presents a 4-connected threefold interpenetrated cds framework. Through structural analysis, it is found that the coordination geometry of metal ions significantly affects the binding behaviors of the ligands and the resultant extended networks of the CPs. Besides, the Hirshfeld surface analyses detailed the surface characteristics of the two CPs. In addition, the thermal stabilities and photoluminescent properties were also investigated. 相似文献
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Qi-Hua Zhao Li-Cun Li Zong-Hui Jiang Dai-Zheng Liao Shi-Ping Yan Rui-Bin Fang 《Journal of chemical crystallography》2004,34(3):191-194
A novel compound formed by copper(II) and a carboxy-substituted nitronyl nitroxide of formula [Cu2(NITpBAH)2Cl4] (NITpBAH = [2-(4-carboxy-phenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl-3-oxide]) has been synthesized. The compound crystallizes in the monoclinic space group P21/c with a = 9.5464(10), b = 12.4501(12), c = 14.3627(14) Å, = 95.200(2)°, and Z = 2. X-ray analysis reveals [Cu2(NITpBAH)2Cl4] units to be linked into infinite chains by radical bridging ligands with N
O of nitronyl nitroxide and substituted carboxy; there are the weak hydrogen bond interactions between chains. 相似文献
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UV-0为母体结构,设计了系列新型含氟衍生物,以增强二苯酮类紫外线吸收剂在涂层表面的含量,提高其抗紫外线性能. 为探讨含氟侧链的引入对几何构型和电子光谱等性质的影响,筛选新型紫外线吸收剂,采用量子化学密度泛函理论在B3LYP/6-31++G**水平上对标题化合物分子几何构型进行了优化和电子光谱研究. 计算结果表明:含氟侧链通过酯键连接时,随着侧链的增长,O17与环B之间的共轭作用减弱,分子共轭体系减小,对紫外线的吸收能力变弱;含氟侧链通过醚键连接时,其在230~290 nm、310~400 nm区间有更强的紫外线吸收能力,同时含氟侧链的长度对紫外吸收曲线的影响较小. 综合考虑衍生物的紫外线吸收能力和的表面富集能力,预测化合物Ⅴ最优. 相似文献
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