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21.
Ligand gave variously colored or fluorescent rings when reacted with several kinds of ions on a ring oven (Schleicher and Schuell filter paper 5892). With ions of Al(III), Be(II), Co(II), Cr(III), Cu(II), Fe(III), and Ni(II) the reactions were sensitive enough to enable application of ring colorimetry or fluorometry (excitation at 366 nm) for quantitation (detection limits, 0.1–2.0 μg of metal). A procedure for estimation of Al(III), Cr(III), and Fe(III) in mixtures was based on reaction with Ligand in combination with EDTA pretreatment, but omitting ion separation. Al(III) could be estimated reliably at its detection-limit-level, in the presence of up to 100 times as much of both Cr(III) and Fe(III). 相似文献
22.
Dubravka Matkovi‐alogovi Zora Popovi Vesna Trali‐Kulenovi Livio Racan Grace Karminski‐Zamola 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o190-o191
The title compound, C8H8N3S+·Cl−·2H2O, has been synthesized and characterized both spectroscopically and structurally. The structure consists of 1,3‐benzothiazole‐6‐carboxamidinium cations, chloride anions and water molecules, all interconnected by hydrogen bonds into a three‐dimensional network. The 1,3‐benzothiazole moiety is inclined to the 6‐amidine group by 36.71 (9)°. 相似文献
23.
Renata Odžak Srđanka Tomić Helena Čičak Zlatko Mihalić Biserka Prugovečki Dubravka Matković-Čalogović 《Structural chemistry》2006,17(4):337-346
Condensation of tetra-O-pivaloyl-α-d-glucopy-ranosyl bromide (1) with three heterocyclic oximes: 3-hydroxyiminoquinuclidine (2), 4-hydroxyiminomethyl-pyridine (3) and N-methyl-2-hydroxyiminomethylimidazole (4) leads to the β-N-glucoconjugates. Conjugates 6 and 7 were synthesized using aromatic compounds 3 and 4 as the starting material. They were obtained in two isomeric forms (E and Z) due to the restricted rotation around the oxime's double bond. The presence of E and Z isomers was proved by comparison of NMR spectra with calculated GIAO/DFT NMR spectra on B3LYP/6-31G(d) level of theory and by X-ray structural analysis of starting oxime reagents. Isomery was not observed in the quinuclidinium glucoconjugate 5. 相似文献
24.
A polar type liquid having a secondary alcohol substituent on a branched alkane skeleton, SOH, was used as stationary phase. The molecules of this stationary phase are nearly isomorphous and isochor with those of the branched alkane, C78, elected as standard, i.e., the molecules of both solvents have nearly the same form and the same size. Partition properties of 158 chosen molecular probes were measured by gas chromatography on SOH and on an SOH-C78 mixture having a volume fraction of thetaOH = 0.5. Based on the resulting data an interaction free enthalpy could be calculated, i.e., the additional effect of the secondary alcohol to partition. Comparison with data determined earlier on another member of this solvent family, POH, having a primary alcohol as interacting group gives information about the effect of steric hindrance on polar type solute-solvent interaction free energies. 相似文献
25.
Miklós Tasi Attila Sisak Ferenc Ungváry Gyula Pályi 《Monatshefte für Chemie / Chemical Monthly》1985,116(8-9):1103-1105
Dicobalt octacarbonyl reacts with alcoholates (RO–) yielding alkoxycarbonylcobalt tetracarbonyls,ROC(O)Co(CO)4.
Reaktion von Alkoxiden mit Dicobaltoctacarbonyl: Abfangen des Co(I) Zwischenproduktes in der Disproportionierung (Basen-Reaktion) mit einer hartenLewis Base (Kurze Mitteilung)
Zusammenfassung Dicobaltoctacarbonyl reagiert mit Alkoxiden (RO–) zu Alkoxycarbonylcobalt tetracarbonylen,ROC(O)Co(CO)4.相似文献
26.
27.
A new synthesis of Mo2(CO)8(-PPh2)2 and W2(CO)8(-PPh2)2 by the reaction of molybdenum and tungsten hexacarbonyls with a tetraazamacrocyclic ligand containing —CH2PPh2 side chains, comprising cleavage of the phosphorus-methylene bond has been performed. The complexes have been investigated by magnetic and spectroscopic measurements and by single-crystal structure analyses. The structural characterization of a new polymorph of Mo2(CO)8(-PPh2)2 has been described. 相似文献
28.
29.
Aleksandar Višnjevac Marija Luić Renata Kobetić Dubravka Gembarovski Biserka Žinić 《Polyhedron》2009,28(6):1057-1064
The synthesis, as well as chemical and structural characterization, of 1-(p-toluenesulfonyl)cytosine (1) and its dinuclear complexes of the composition Pd2(1-TosC?–N3,N4)4 (3) and Pd2(1-TosC?–N3,N4)2DMSO2Cl2 (4) by means of ESI-MS, IR, 1H NMR and X-ray single crystal analysis are described. Ligand 1 exists in the preferred aminooxo tautomeric form, while both dinuclear complexes reveal the presence of the iminooxo form of the ligand, where 1-TosC? stands for the anion of the cytosine derivative of 1, bridging two palladium atoms. Complex 3 has a paddlewheel structure with two square-planar coordination spheres, consisting of four N atoms each, mutually parallel and perpendicular to the interpalladium vector. Complex 4 is characterized by two mutually parallel square-planar coordination spheres consisting of two nitrogens, sulfur from the solvent molecule and a chloride. A feasible chemical route for the formation of 3 and 4 via the kinetically favoured mononuclear complex Pd(1-TosC–N3)2Cl2 (2) is proposed, based on the IR, 1H NMR, mass spectrometry, elemental analysis and X-ray structure analysis data. 相似文献
30.
We establish the connection between the standard intertwining operators for a square integrable representation and its Aubert involution. In the cases of special orthogonal groups and symplectic groups, we define the R-group for a nontempered unitary representation, under the assumption that the Aubert involution of the representation is square-integrable. 相似文献