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1.
Summary The interaction of 1-benzoin-4-phenylthiosemicarbazone (H2 BPS) with some transition metal ions has been investigated. The ligand can function as a tridentate chelating agent, giving M(HBPS)2 and M(BPS). Potentiometric studies proved that the mechanism of chelation is based on hydrogen ion liberation. Spectral studies in solution show that the ligand could be used for the microdetermination of CuIIions. On the basis of magnetic and spectral data, an octahedral structure is proposed for the CoII and NiII complexes and a square-planar structure for the CuII complex. The corrosion inhibition of aluminium in Cl3CCO2H using H2BPS is studied. The electrical conductivity of H2BPS and of its complexes have been measured. The ligand shows an activation energy in the range of semiconducting materials. The antimicrobial activity of all compounds has also been demonstrated.  相似文献   
2.
Summary Several new complexes of the title ligand (H2MPTS) with CoII, NiII, CuII, and CdII have been prepared. Structural assignments of the complexes have been made based on elemental analysis, molar conductivity, magnetic moment and spectral (i.r.,1H n.m.r., reflectance) studies. The compounds are non-conductors in dimethylsulphoxide. The neutral molecule is coordinated to the metal(II) sulphate as a bidentate ligandvia the two carbonyl groups. The ligand reacts with the metal(II) chlorides with the liberation of two hydrogen ions, behaving as a bianionic quadridentate (NONO) donor. Enolization is confirmed by the pH-titration of H2 MPTS and its metal(II) complexes against NaOH. A distorted octahedral structure is proposed for the CuII complex, while a square planar structure is suggested for both CoII and NiII complexes. The stoichiometry of the complexes formed in EtOH and buffer solutions, their apparent formation constants and the ranges for obedience to Beer's law are reported for CoII, NiII and CuII ions. The ligand pK values are calculated. The antimicrobial activity of H2 MPTS and its CoII, NiII, CuII and MnII complexes is demonstrated.  相似文献   
3.
The redox behaviour of hexakismethylisonitrilmanganese(I) [MnL 6 +] has been studied in acetic acid, dichloromethane, 1,2-dichloroethane, propylenecarbonate, butyrolactone, methanol, ethanol, nitromethane, acetonitrile, N-methyl-2-pyrrolidinone, dimethylformamide, dimethyl sulfoxide and water. The reversible diffusion-controlled oxidation MnL 6 +/MnL 6 2+ could be observed in all solvents studied, on both the dropping mercury electrode and the stationary platinum electrode. Employing tetrabutylammonium perchlorate as supporting electrolyte, the oxidation MnL 6 2+/MnL 6 3+ was observable only in acetic acid, nitromethane, 1,2-dichloroethane, dichloromethane, propylenecarbonate, butyrolactone and acetonitrile. In all other solvents oxidation of the solvent preceded the oxidation MnL 6 2+/MnL 6 3+. Poorly defined polarographic waves attributable to the one electron reduction of the MnL 6 + were observed in butyrolactone, propylenecarbonate, acetonitrile, dimethylformamide, N-methyl-2-pyrrolidinone and dimethyl sulfoxide. All potential values were recorded versus bisbiphenylchromium(I)-iodide [BBCr(I)J], the problems of measuring against external aqueous reference electrodes are discussed. The redox potential of the process MnL 6 +/MnL 6 2+ was found to be a function of the donor properties of the solvents used; the effects of outer sphere coordination on the redox behaviour of this couple are discussed. No effect of the supporting electrolytes tetrabutylammonium perchlorate, tetraethylammonium nitrate and tetraethylammonium perchlorate on the redox behaviour of MnL 6 + was found. The UV-spectrum of MnL 6(PF6)2 has been recorded.  相似文献   
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5.
Summary Reaction of one mole of acetylacetone with two moles of 4-phenylthiosemicarbazide yields the unusual Schiff base, MeC(=N-NHCSNHPh)CH2C(=NNHCSNHPh)Me. APT = H2L) acetylacetone bis(4-phenylthiosemicarbazone). The complexes of CoII, NiII, CuII, ZnII and UVIO2 have been prepared and characterized by analytical, i.r., electronic spectral and magnetic measurements. The CoII, NiII and CuII complexes have been assigned square-planar stereochemistry on the basis of magnetic and spectroscopic studies. The ligand is a neutral or dibasic quadridentate SNNS donor as revealed by i.r. spectral studies.  相似文献   
6.
Summary Complexes of CoII, NiII, CuII, ZnII, CdII, HgII and UO 2 II with benzil bis(4-phenylthiosemicarbazone), H2BPT, have been synthesized and their structures assigned based on elemental analysis, molar conductivity, magnetic susceptibility and spectroscopic measurements. The i.r. spectra suggest that the ligand behaves as a binegative quadridentate (NSSN) (CoII, CuII, HgII and UO 2 II complexes) or as a binegative quadridentate-neutral bidentate chelating agent (NiII, ZnII and CdII complexes). Octahedral structures for the CoII and NiII complexes and square-planar structure for the CuII complex are suggested on the basis of magnetic and spectral evidence. The crystal field parameters (Dq, B and B) for the CoII complex are calculated and agree fairly well with the values reported for known octahedral complexes. The ligand can be used for the microdetermination of NiII ions of concentration in the 0.4–6×10–4 mol l–1 range and the apparent formation constant for the species generated in solution has also been calculated.  相似文献   
7.
Radiation exposure of medical staff during cardiological and radiological procedures was investigated. The exposure of medical staff is directly connected to patient exposure. The aim of this study was to determine the distribution of doses on uncovered part of body of medical staff using LiF thermoluminescent (TL) dosimeters in seven locations.Individual Kodak film dosimeters (as authorized dosimetry system) were used for the assessment of medical staff's effective dose. Results achieved on dose distribution measurements confirm that wearing only one film badge under the lead apron does not provide enough information on the personal dose.The value of estimated annual doses on eye lens and extremities (fingers) were in good correlation with international publications.  相似文献   
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9.
Polypyrrole‐zirconium complex has been synthesized by reacting 2‐amino‐3,4‐dicyano‐5‐mercaptopyrrole with zirconium nitrate in absolute ethanol under reflux for 24 h. The product has been characterized by elemental analyses, FTIR spectroscopy, in addition to thermal analysis (TGA and DSC) and its solubility has been investigated. The DC electrical conductivity variation of polypyrrole‐zirconium complex has been studied in the temperature range 300–500 K after annealing for 24 h at 100°C and doping with I2, FeCl3 and CuCl2 · H2O for comparison. An attempt has been made to interpret the DC electrical conductivity behavior and thermal properties to chain length, dopant used, polymer structure and attached groups.  相似文献   
10.
3-Amino-5-phenyl-2-ethoxycarbonylthieno[2,3-c]pyridazine (6) was prepared by reaction of 4-cyano-6-phenylpyridazine-3(2H)-thione (4) with ethyl chloroacetate in the presence of sodium ethoxide. Hydrazinolysis of compound 6 yielded the corresponding carbohydrazide, (9) which on treatment with acetylacetone and ethyl acetoacetate produced the novel thieno[2,3-c]pyridazines (10 and 11). Treatment of compound 9 with nitrous acid yielded the corresponding carboazide (13), which upon boiling in toluene furnished imidazo[4′,5′:4,5]thieno[2,3-c]pyridazine (15). Pyrimidothienopyridazines (1618) were achieved by cyclocondensation of compound 9 with some reagents, namely acetic anhydride, formic acid, and triethyl orthoformate. The newly synthesized compounds were confirmed by elemental analyses and spectral data. The antibacterial activities of the new compounds were also evaluated.  相似文献   
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