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911.
用传统湿式浸渍法制备了La2O3掺杂的商业γ-Al2O3负载的沼气重整催化剂Ni-Co/La2O3-γ-Al2O3, 并用程序升温加氢(TPH)、程序升温氧化(TPO)、程序升温表面反应(TPSR)、程序升温脱附(TPD)及脉冲实验对催化剂进行了表征. 结果表明, 沼气重整过程中Ni-Co/La2O3-γ-Al2O3催化剂上的表面碳物种主要来源于CH4的裂解, CO2的贡献很小. CH4裂解能够产生三种活性不同的碳物种, 即Cα、Cβ与Cγ. 随着反应的进行, Cα物种减小而Cβ与Cγ物种增加, 且Cγ物种能够转变为惰性的石墨碳. 重整反应过程中CH4与CO2的活化能相互促进. 催化剂表面的O物种与C反应生成CO或与CHx反应生成CHxO再分解为CO与吸附态的H物种, 可能是Ni-Co/La2O3-γ-Al2O3催化剂上沼气重整的速率控制步骤. 相似文献
912.
913.
914.
The fabrication of cobalt/polyaniline nanocomposite was performed using a simple chemical method. It was characterized by using TEM and FTIR techniques. The nanocomposite was applied as a modifier in a carbon paste electrode for selective determination of penicillamine. Penicillamine reacts with emeraldine polyaniline by using 1,4, Michael addition reaction. It can decrease the voltammetric peak current of emeraldine polyaniline. The effects of pH and potential sweep rate on the response of the electrode were investigated. Differential pulse voltammetry was applied for quantitative determination. Dynamic linear ranges were obtained in the ranges of 1.0×10?8–1.0×10?7 mol L?1 and 1.0×10?9–1.0×10?8 mol L?1. 相似文献
915.
《Journal of Coordination Chemistry》2012,65(17-18):1591-1601
The reaction of ferrocenylacetylide compounds with Co2(CO)8 at room temperature affords four complexes bearing ferrocenyl units with approximately tetrahedral (μ-alkyne)dicobalt moieties [R–(C≡C) n –R′] [Co2(CO)6] n ′ [R?=?C5H5FeC5H4-C(CH3)2-C5H4FeC5H4, R′?=?H, n?=?1, n′?=?1 (1); R?=?C5H5FeC5H4 [ferrocenyl (Fc)], R′?=?–CH=CHCl, n?=?1, n′?=?1 (2); R?=?Fc, R′?=?Fc, n?=?2, n′?=?1 (3), n′?=?2 (4)]. The compounds were characterized by elemental analysis, IR, 1H(13C) NMR, MS and single-crystal X-ray diffraction analysis. The X-ray analyses show that coordination of the carbon–carbon triple bond and the dicobalt unit result in the formation of a Co2C2 tetrahedral core, and the substituents on the acetylenic units show a distortion from linearity that reflects this coordination mode. 相似文献
916.
《Journal of Coordination Chemistry》2012,65(12):1902-1913
Two new, large 1,3,5-triazine-based ligands with only N-donor functions were synthesized as well as the Co(II) salt [Co(DHPTBenz)2](Br1.7(OH)0.3) · 4.8H2O (DHPTBenz = 2,4-bis-(2-diphenylmethylene)-hydrazinyl-6-piperidin-1-yl-1,3,5-triazine). Single crystal X-ray structures of the Co(II) complex, DHPTBenz, and 2,4-dichloro-6-(piperidin-1-yl)-1,3,5-triazine (DCPT) have been determined. The last compound was used as starting material for the tridentate DHPTBenz ligand. Spectroscopic data of the ligand and the starting materials are reported. The Co(II) ion in the complex is distorted octahedrally coordinated by six N atoms of two DHPTBenz ligands. One N atom of the triazine ring of each ligand bonds axially with short distances of 1.953(3) Å and 1.954(3) Å, respectively, whereas two of the hydrazine-N atoms of two ligands form the equatorial plane with an average Co–N bond distance of 2.313 Å. The complex cation has a slightly elongated, nanometer-scaled ball shape with the longest diameter of 1.82 nm. 相似文献
917.
《Journal of Coordination Chemistry》2012,65(13):1381-1386
A mixed Co–Ag complex with 2,6-dicarboxypyridine (H2PDC), AgCo(PDC)2, was synthesized under hydrothermal conditions. The complex adopts a 2D layer structure formed by intramolecular π-stacking. Each Co(III) ion is chelated by two 2,6-dicarboxypyridine anions to give the [Co(PDC)2]? anion that is further extended by Ag+ to form 44 square grids. 相似文献
918.
《Journal of Coordination Chemistry》2012,65(13):1105-1111
A novel layered cobalt phosphate with a racemic 1,2-diaminopropane templating agent, [CH2(NH3)CH(NH3)-CH3][CoPO4]2, has been synthesized and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P21/c with a = 10.457(2), b = 7.849(1), c = 6.692(1)?Å, β = 103.30(1)°, V = 534.5(2)?Å3, Z = 2. The combination of cobalt phosphate anion layers and doubly protonated cationic 1,2-diaminopropane templates is mainly through ionic bonding. The crystal structure is stabilized by a network of hydrogen bonds between layers and templating agents. 相似文献
919.
《Journal of Coordination Chemistry》2012,65(7):1289-1298
Aquabis(2-benzoylbenzoato)(1,10-phenanthroline)cobalt(II) and aquabis(2-benzoylbenzoato)(butanol)(1,10-phenanthroline)nickel(II) have been prepared and characterized by elemental analyses, IR and electronic spectroscopy, magnetic measurements, and single-crystal X-ray diffraction. [Co(bba)2(H2O)(phen)] (1) and [Ni(bba)2(H2O)(butOH)(phen)] (2) consist of neutral monomeric units and crystallize in the monoclinic (P2(1)) and triclinic (P 1) crystal systems, respectively. The cobalt(II) and nickel(II) sit on inversion centres and exhibit distorted octahedral coordination. Phen is bidentate chelating. In 1, bba is both monodentate and bidentate, whereas in 2 bba is only monodentate. bba ligands are coordinated to metal(II) with carboxylates and IR spectra of both complexes display characteristic absorptions of carboxylate anions {ν(OCO)asym and ν(OCO)sym} of bba. Thermal analysis shows that mass losses of 1 from 105°C to 456°C correspond to decomposition of phen and bba, while for 2 these occur at 271–529°C. 相似文献
920.
《Journal of Coordination Chemistry》2012,65(14):2388-2398
The cobalt(II) and nickel(II) chelates of Schiff bases, derived by condensing 4-butyryl-3-methyl-1-phenyl-2-pyrazolin-5-one (BMPP) with o-, m-, p-phenylenediamine, benzidine, and ethylenediamine have been synthesized and characterized by elemental analyses, thermogravimetric analyses (TGA), conductance data, magnetic measurements, IR, 1H NMR, 13C NMR, mass, and electronic spectroscopies. Each of the Schiff bases was an ONNO donor to metal forming chelates formulated as [M(L)(H2O)2] n with M = Ni(II) and Co(II) and L is the di-anion of the Schiff base. The monomeric (n = 1) and dimeric (n = 2) species of these metal chelates, based on available evidence, are suggested. 相似文献