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111.
The novel calixarene-linked discotic triphenylene 5a and 5b were synthesized in good yields via click chemistry. Structural and conformational characterization of new compounds had been achieved by NMR, MS, and elemental analysis. Their liquid crystalline behaviors before and after complexation were studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. The neat compounds 5a and 5b showed mesophase but the complexes of 5a and 5b with metallic salts exhibited no liquid crystal behaviors. 相似文献
112.
Jun-Hui Xue Xiao-Hui Hua Li-Min Yang Wei-Hong Li Yi-Zhuang Xu Guo-Zhong Zhao Gao-Hui Zhang Ke-Xin Liu Jia-Er Chen Jin-Guang Wua 《中国化学快报》2014,25(6):887-891
The novel coordination structures of europium and terbium chloride-picolinamide complexes (EuCl3-(C6H6N2O)2.5H2O, Eu-pa and TbCl3.(C6H6N2O)2.5H2O, Tb-pa) are reported. The crystal structures in the solid state are characterized by X-ray single crystal diffraction, FTIR, Raman, FIR, THz and luminescence spectroscopy. In the crystal structures, the pyridyl nitrogen and carbonyl oxygen atoms in picolinamide are coordinated to the metal ions to form a five-membered ring structure. The experimental results indicate the similar coordination structures of Eu and Tb-pa complexes and the changes of hydrogen bonds and conformation provide models for the coordination structures of the ligands induced by complexation. The results of lanthanide ions with ligands having amide groups. 相似文献
113.
The derivatized cyclotetrachromotropylene host forms complexes of 1:1 host to guest stoichiometry with tetraalkylammonium cations and amino acids whereas complexes of 1:2 host to guest stoichiometry are formed with mono and diprotonated amines in an aqueous solution. Both electrostatic and hydrophobic interactions are involved in the complexation. 相似文献
114.
Eu(3+)在HAc-NaAc(pH4.6)溶液中与五碳醛糖有弱的络合作用,用循环伏安法和微分脉冲极谱可以观察到D-核糖,D-阿拉伯糖,D-木糖对Eu(3+)还原波形的络合影响,使还原和氧化过程变得较为可逆,其中D-核糖最为明显,而来苏糖无影响.Eu(3+)与氨基酸在相同实验条件下有络合作用,且在汞电极上有吸附现象,因此分别加入L-苯丙氨酸、L-组氨酸和L-蛋氨酸等,进一步改善了Eu(3+)的波形而接近于可逆氧化-还原过程,其中以Eu(3+)-D-核糖-L-苯丙氨酸最明确。绘出了在电极表面形成三元络合物的示意图。 相似文献
115.
M. Zafer Köylü Nadir Demirel F. Doganel Polat Ali Yιlmaz Halil Hoşgören Metin Balci 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(1-2):51-54
The complexation of the crown ethers with Na+ ion was studied. 1H-NMR chemical shifts are discussed in terms of structural modification as well as also binding studies with UV–vis spectra
were included.
This revised version was published online in July 2005 with a corrected issue number.
An erratum to this article is available at . 相似文献
116.
Keqiang Dmg Qingfei Wang Zhenbm Jia Na Tian Ning Wang Ruting Tong Xinkui Wang Huibo Shao 《中国化学会会志》2002,49(2):185-190
In this paper, Schiffbases were investigated using cyclic voltammetry (CV) and impedance electrochemical spectroscopy (EIS) techniques by means of self‐assembled monolayers for the first time, where a 0.1 M KCl solution and the redox couple of Fe(CN)63?/Fe(CN)64?were used as the electrolyte and probing‐pin, respectively. The monolayers formed by the employed Schiff base were proved to be relatively stable, and its electrochemical response in the studied system with different pH values was also de scribed clearly with CV and EIS plots. The results show that the monolayer of Schiff bases could exist in the solution with pH value from 2 to 10. In the EIS measurement in the concentration range from 10?5 M to 5× 10?4 M, a nearly linear relation ship between the charge transfer resistance (Rct) and the logarithm concentration of Cu2+was observed, suggesting that Cu2+ could be titrated with the EIS method quasi‐quantitatively. The phenomenon agreed with the former report very well. Using the self‐assembled monolayers to study Schiff bases with the electrochemical method is the major contribution of our work. 相似文献
117.
An interpolymer specific interaction of polymers with complementary proton donor units and proton acceptor units was studied with viscometry. In this study, poly(styrene-co-octyl acrylate-co-acrylic acid) as proton donating polymer (PDP) and poly(styrene-co-octyl acrylate-co-4-vinylpyridine) as proton accepting polymer (PAP) with different macromolecular chain compositions were prepared by emulsion copolymerization. Complexed solutions formed by PDP and PAP were studied with a novel interaction criterion ka based on viscosity enhance factor. The effects of macromolecular chain compositions on the ability to interpolymer interaction and complex stoichiometry were discussed. The results showed that long chain alkyl acrylate units play an important role in the interpolymer specific interaction. 相似文献
118.
119.
Feyyaz Durap Nermin Biricik Bahattin Gümgüm Saim Özkar Wee Han Ang Zhaofu Fei Rosario Scopelliti 《Polyhedron》2008
N,N-Bis(diphenylphosphino)ethylaniline compounds, [Ph2P]2N-C6H4-C2H5, with ethyl groups at the ortho- and para-positions have been synthesized. Oxidation of the aminophosphines with hydrogen peroxide, elemental sulfur and selenium gave the corresponding oxides, sulfides and selenides [Ph2P(E)]2N-C6H4-C2H5 (E = O, S, Se). Complexes [MCl2{(Ph2P)2N-C6H4-(C2H5)}] (M = Pd, Pt) and [Cu{(Ph2P)2N-C6H4-C2H5}2]PF6 were obtained by the reaction of N,N-bis(diphenylphosphino)ethylaniline with [MCl2(COD)] (M = Pd, Pt) and [Cu(MeCN)4]PF6. The new compounds were characterized by NMR, IR spectroscopy and microanalysis. In addition, representative solid-state structures of the palladium and platinum complexes were determined using single crystal X-ray diffraction analyses. 相似文献
120.
The thermodynamic equilibria of copper(II), zinc(II) and calcium(II) with N,N′-bis[2(2-pyridyl)-methyl]pyridine-2,6-dicarboxamide (L1) have been studied at 25 °C and an ionic strength of 0.15 mol dm−3. Spectroscopic studies suggest metal ion complexation promotes deprotonation and coordination of the amide nitrogens resulting in overall tetragonal coordination of Cu2+. Blood–plasma modelling predicts that Cu(II) competes effectively against Zn(II) and Ca(II) for L1 in vivo. Octanol–water partition coefficient studies show that Cu(II)–L1 complexes are reasonably lipophilic. However, the CuL1H−2 species which predominates at the physiological pH of 7.4 has poor superoxide dismutase activity. Bio-distribution experiments showed activity accumulation and retention in the body of about 50% of the injected dose for the [64Cu]Cu(II)–L1 complex after 24 h. 相似文献