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91.
Ghosh K Semwal A Nayak SK Banerjee SB Banerjee M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(4-5):1122-1125
[60]- and [70]Fullerenes have been shown to form 1:1 supramolecular complexes with bis[2-(5,11,17,23,29,35-hexa-tert-butyl-37,38,39,40,41-pentahydroxycalix[6]arenyl-oxy ethyl ether) (1) and 5,11,17,23,29,35-hexa-tert-butyl-37,38,40,41-tetra hydroxyl-39,42-(crown-4)calix[6]arene (2) in CHCl3 medium by electronic absorption spectroscopy. Formation constants (K) of the complexes of [60]- and [70]fullerenes with 1 and 2 have been determined at room temperature from which free energy of formation values of the complexes have been estimated. The very high formation constant value of [60]fullerene/1 complex (5900 dm3 mol-1) in indicative of formation of inclusion complex. Moreover, PM3 calculations reveal that intermolecular interaction between [60]fullerene and 1 proceeds through quite deep energy molecular orbital. 相似文献
92.
Mine Sulak Ak Hasalettin Deligöz 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):115-123
Four new azocalix[4]arenes {5,11,17,23-tetrakis[(2-hydroxy-5-tert-butylphenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (1), 5,11,17,23-tetrakis[(2-hydroxy-5-nitro phenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (2), 5,11,17,23-tetrakis[(2-amino-5-carboxylphenylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (3) and 5,11,17,23-tetrakis[(1-amino-2-hydroxy-4-sulfonicacidnapthylazo)]-25,26,27,28-tetrahydroxycalix[4]arene (4)} have been synthesized from p-tert-butylphenol, p-nitrophenol, p-aminobenzoic acid and 1-amino-2-hydroxy-4-sulphonic acid by diazo coupling reaction with p-aminocalix[4]arene. The resulting ligands (1–4) were treated with three transition metal salts (e.g., CuCl2·2H2O, NiCl2·6H2O or CoCl2·6H2O). Cu(II), Ni(II) and Co(II) complexes of the azocalix[4]arene derivatives were obtained and characterized by UV-vis, IR,
1H-NMR spectroscopic techniques and elemental analysis. All the complexes have a metal:ligand ratio of 2:1. The Cu(II) and
Ni(II) complexes of azocalix[4]arenes are square-planar, while the Co(II) complexes of azocalix[4]arenes are octahedral with
water molecules as axial ligands. The solvent extraction of various transition metal cations from the aqueous phase to the
organic phase was carried out by using azocalix[4]arenes (1–4). It was found that, azocalix[4]arenes 1, 2 and 3 examined selectivity for transition metal cations such as Ag+, Hg+ and Hg2+. In addition, the thermal stability of metal:azocalix[4]arene complexes were also reported.
Dedicated to Prof. Dr. Mustafa Yılmaz on the occasion of his 50th birthday 相似文献
93.
Maria Atanassova Victoria Lachkova Nikolay Vassilev Sabi Varbanov Ivan Dukov 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):173-179
The synergistic solvent extraction of five selected lanthanoid ions (La3+, Nd3+, Eu3+, Ho3+ and Lu3+) with a 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone(HP) and the 5,11,17,23-tert-butyl-25,26,27,28-tetrakis(dimethylphosphinoylmethoxy)calix[4]arene, (S) in CHCl3 has been studied. It was found that in presence of this phosphorus-containing calix[4]arene the lanthanoids have been extracted
as LnP3 · S. On the basis of the experimental data, the values of the equilibrium constants have been calculated. The influence of
the synergistic agent on the extraction process has been discussed. A synergistic effect of almost three orders of magnitude
occurs in the extraction of Ln(III) with mixture of HP and S. The values of the separation factors (S.F.) between the adjacent
elements have been evaluated.
On the basis of the IR and NMR spectra the stoichiometry and the structure of the solid complexes of Eu(III) with HP and Eu(III)
with HP and S were proposed. 相似文献
94.
Zhi Qiang Shi Ya Qing Feng Bing Zhao Wen Xiang Wang 《中国化学快报》2007,18(12):1493-1495
A novel series of N-alkylphthalimidylaminocarbonylmethoxylcalix[4]arenes with the reaction between 4-(N-bromoacetyla- mino)-phthalimide derivatives and calix[4]arene has been synthesized and structurally characterized by IR,~1HNMR and MS.From their analysis data,it was found that compounds 7a-7d adopted a cone conformation. 相似文献
95.
GU Jin-ying HU Xiao-jun SHI Xian-fa LI Yan-jun QI Yong-lu JI Liang-nian 《高等学校化学研究》2007,23(2):241-244
Introduction Calixarenes are versatile host molecules for molecular recognition and supram olecular assembly be-cause its functional groups can be readily introduced in-to the phenolic OH or the para position to realize a wide variety of functions[1-5]. 相似文献
96.
Serkan Erdemir Mustafa Tabakci Mustafa Yilmaz 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(3-4):197-202
Herein the synthesis and extraction abilities of new d-/l-phenylalaninol substituted p-tert-butylcalix[4]arene triamide derivatives (3 and 4) towards amino acids are reported. These compounds (3 and 4) have been easily synthesized via aminolysis of p-tert-butylcalix[4]arene trimethylester (2) with d-/l-phenylalaninol in methanol-toluen solvent system at one step. The extraction properties of the prepared chiral calix[4]arene
triamide derivatives (3 and 4) towards some selected amino acid methylesters are studied by liquid–liquid extraction. Results show that these chiral calix[4]arene
triamide derivatives (3 and 4) exhibited a good affinity towards all amino acid species without any remarkably discrimination. 相似文献
97.
A series of aryl pyrogallol[4]arenes were efficiently synthesized in excellent yields by cyclocondensation of pyrogallol with aromatic aldehydes under microwave irradiation. The structures of aryl pyrogallol[4]arenes were confirmed by characterization of their acylated derivatives. Under microwave irradiation, alkylation reactions of aryl pyrogallol[4]arenes with some alkylating reagents such as n-butyl iodide, benzyl chloride, and ethyl α-chloroacetate were also finished quickly to yield fully O-alkylated products. The 1H NMR spectra and crystal structures showed that the acylated and alkylated aryl pyrogallol[4]arenes existed mainly in rctt (cis-trans-trans) configuration. 相似文献
98.
Solvent extraction of a mixture of PbII, MnII, FeIII, CoII, NiII and CdII in aqueous perchlorate medium by a phosphorylated hexahomotrioxacalix[3]arene (calix‐3) in dichloromethane shows a significant selectivity towards lead ions. The ligand can also be incorporated into a membrane to provide a new lead ion‐selective electrode (PbII‐ISE). A plasticized PVC membrane containing 30% PVC, 53.5% ortho‐nitrophenyloctylether (NPOE), 4.5% sodium tetraphenylborate (NaTPB) and 12% ionophore was directly coated on a graphite rod. This sensor gave a good Nernstian response of 29.7 ± 0.7 mV decade?1 over a concentration range of 1 × 10?8 – 1 × 10?4 M of lead ions, independent of pH in the range 3‐7, with a detection limit of 0.4 × 10?8 M. The dynamic response time of the electrode to achieve a steady potential was very fast and found to be less than 7 s. The selectivity relative to Ag+, NH4+, Li+, Na+, K+, Ca2+, Sr2+, Ba2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Fe3+, La3+, Sm3+, Dy3+, Er3+, Y3+ and Th4+ was examined. The electrode exhibits adequate stability with good reproducibility (with a slope of 29.6 ± 1.5 mV for 8 weeks). The characteristics of the sensor are compared with those of a tetraphosphorylated calix[4]arene (calix‐4) based PbII‐ISE, reported recently. The electrode was successfully used as an indicator electrode for a potentiometric titration of a lead solution using a standard solution of EDTA. The applicability of the sensor for lead ion measurements in various synthetic samples was also investigated. 相似文献
99.
A new diphosphazane ligand, Ph2PN(CHMe2)P(Ph){1,3-dimethoxycalix[4]arene} (2), in which the P–N–P unit is appended to calix[4]arene backbone, and its PdCl2 complex (3) have been synthesized. The structures of the conformers of both the compounds in solution have been elucidated with the help of two-dimensional NMR experiments. Single crystal X-ray diffraction studies reveal the partial cone and cone conformations of the calixarene unit in the ligand (2) and the Pd-complex (3), respectively. 相似文献
100.
Aurore Fraix Vanna Torrisi Giovanni Marletta Salvatore Sortino Placido G. Mineo Gaetano A. Tomaselli 《Supramolecular chemistry》2016,28(5-6):485-492
AbstractA poly(p-phenyleneethynylene) polymer (PCF[5]), bearing two π-rich cone-like calix[5]arene cavities (assembling cores) attached to a rigid p-phenyleneethynylene spacer, was synthesised by a Pd-catalysed cross-coupling reaction. UV–vis absorption and fluorescence spectroscopies combined with dynamic light scattering measurements provide evidence for the self-assembly of PCF[5] (homopolytopic host molecule) with a complementary C60 fulleropyrrolidine (C60-Pyr) guest in solution, in the construction of a supramolecular polymer network. Atomic force microscopy analysis of PCF[5]/C60-Pyr highlights the formation of a bicontinuous network consisting of a uniform distribution of prominent structures, within a polymeric background forming a biphasic structure. 相似文献