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991.
Various substituted benzaldehydes were converted into benzoate esters with household bleach and sodium iodide in an alcohol solvent. The reaction works best with methanol. Only 4-chlorobenzaldehyde, 3-nitrobenzaldehyde, and 4-nitrobenzaldehyde reacted completely with 1-propanol under these conditions.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
992.
N,N′‐Dibenzylethylenediamine is presented as a new, efficient, and versatile bidentate ligand suitable for the copper catalyzed formation of the C‐N bond. This bidentate ligand has been demonstrated to facilitate the copper catalyzed cross‐coupling reactions of aryl iodides with amides to afford the desired products in good to excellent yields. 相似文献
993.
The polyfluoroalkyl-lactonization of 5-hexenoic acids with the polyfluoroalkyl iodides initiated by sodium dithionite was carried out in aqueous acetonitrile, providing an efficient method for the synthesis of fluorine-containing δ-valerolactones. Formation of RfCH2CHCH(CH2)2COOH appeared to be unexpected minor product in sulfinatodehalogenation reagents. 相似文献
994.
Recent developments in dynamic kinetic resolution 总被引:1,自引:0,他引:1
Hélène Pellissier Author Vitae 《Tetrahedron》2008,64(8):1563-1601
995.
Mohammad Navid Soltani Rad Somayeh Behrouz Ali Khalafi-Nezhad 《Tetrahedron letters》2008,49(7):1115-1120
An efficient and selective method for esterification of alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of RCO2Na (R: alkyl and aryl), TsIm, and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF to afford the corresponding esters in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
996.
Prof. Dr. J. Armando Luján-Montelongo Dr. Jeferson B. Mateus-Ruiz Ricardo M. Valdez-García 《European journal of organic chemistry》2023,26(9):e202201156
This review provides a comprehensive overview of strategies and methodologies for reducing C−O and heteroatomic−oxygen bonds (N−O, S−O, P−O) using I2/I−, as well as other synthetically relevant bonds such as C−C, N−N, C−N, C−X, C−S. It highlights and discusses most of the mechanistic details provided by the original authors. Selected examples of other halides (Br and Cl) as reductants are also covered. 相似文献
997.
Nico Leupold Philipp Ramming Irene Bauer Christina Witt Jennifer Jungklaus Prof. Dr. Ralf Moos Dr. Helen Grüninger Dr. Fabian Panzer 《欧洲无机化学杂志》2023,26(8):e202200736
Here, we investigate in detail the impact of the size of the methylammonium iodide (MAI) reactants in the mechanochemical powder synthesis of the halide perovskite methylammonium lead iodide (MAPbI3). Morphology and structural characterizations by scanning electron microscopy and X-ray diffraction reveal that with increasing MAI reactant size, the particle size of the perovskite powder increases, while its defect density decreases, as suggested by nuclear quadrupole resonance spectroscopy and photoluminescence investigations. The reason for this behavior seems to be associated to the sensitive influence of the MAI size on the time durations of MAPbI3 synthesis and delayed MAPbI3 crushing stage during ball milling. Thus, our results emphasize the high importance the reactant properties have on the mechanochemical synthesis of halide perovskites and will contribute to enhance the reproducibility and control of the fabrication of halide perovskites in powder form. 相似文献
998.
《Analytical letters》2012,45(15):2763-2774
Abstract The oxidation of iodide to iodine by nitrous acid in aqueous acidic medium takes place catalytically in the presence of dissolved oxygen and can be followed spectrophotometrically at 288 and 352 nm. An indirect molar absorptivity for nitrite on the basis of I3 ? formation can be as high as 8.5×105 L mol?1 cm?1 at 288 nm. Analytical curves were established. The iodine released in the catalytic cycle can also be titrated with thiosulfate. The reaction is pseudo–second‐order in oxygen consumed, with t1/2=15.7 min at 25°C. A rate determining step could be the NO · O2 as the activated species. Measurements of the iodine formed at catalytic conditions was used to determine nitrite in meat extracts and NOx in car exhausts. 相似文献
999.
《Journal of Coordination Chemistry》2012,65(3-4):191-195
Abstract A direct method of obtaining PbEnI2.DMSO is reported. The crystal structure of the compound was determined by X-ray techniques. PbEnI2.DMSO is triclinic, space group P 1, C4H14I2N2PbS, a=10.225(3), b=10.132(3), c=6.900(2) Å; α=90.83(2), β=88.30(2), γ=106.35(4)°; V=685.6(4) Å3; z=2, calculated density 2.92 gcm?3. Neutral PbEnI2 complexes are associated with DMSO molecules via H-bonds. The lead(II) ion is covalently linked with a chelated En molecule (Pb-N 2.46–2.48 Å) and I? anions (Pb-I 3.087–3.343 Å). Covalently bonded atoms form an umbrella-like coordination Pb(II) polyhedron. The side containing the lone electron pair of the lead(II) ion has coordination completed by two I? anions of neighbouring molecules with the Pb-I 3.621–3.627 Å. 相似文献
1000.
《Analytical letters》2012,45(9):2051-2058
Abstract The present paper reports a new chemiluminescence system, i.e, acetone-H2O2?C10?, which can be catalyzed by iodide ion (I?). Based on this catalysis, a new chemiluminescence method for the determination of trace iodide ion is proposed. the optimum conditions are reported in this note. the detection limit is 2 × 10?11 g/ml I?, the linear dynamic range is 4 × 10?10 g/ml to 3 × 10?7 g/ml I?, and the variation coefficient at an iodide concentration of 5 × 10?9 g/ml I? (n=10) is 4.6%. the method has been satisfactorily applied to the determination of trace iodide ion in water. 相似文献