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111.
112.
I. A. Baidina G. I. Zharkova N. V. Pervukhina S. A. Gromilov I. K. Igumenov 《Journal of Structural Chemistry》2004,45(4):678-687
Synthesis of volatile complexes based on -ketoimine pivalyltrifluoroacetone, C(CH3)3C(NH)CH2COCF3, is described. The general formula of the complexes is M(L)2, where M = Cu, Ni, Pd. Complexes of this kind with Ni and Pd were obtained for the first time. The Cu and Pd complexes were found to be isostructural. A comprehensive crystal-chemical study showed that all structures are molecular and built of trans-complexes. The central atom has a square plane environment. The average M-O and M-N distances are nearly equal in all compounds: 1.84 , 1.92 , and 1.98 for Ni, Cu, and Pd complexes, respectively; the mean values of the O-M-N chelate angles are 93.4°, 91.9°, and 92.7°, respectively.Original Russian Text Copyright © 2004 by I. A. Baidina, G. I. Zharkova, N. V. Pervukhina, S. A. Gromilov, and I. K. IgumenovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 713–722, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
113.
Mahendra Madegowda Doreswamy Beeranahally H. Sridhar Mandayam A. Prasad Javaregowda S. Khanum Shaukath A. Shashikanth Sheena Sudha Belagur S. 《Structural chemistry》2004,15(3):211-214
Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P21/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity. 相似文献
114.
Marco Arfelli Giovanni Cossu Giulia Mattogno Carla Ferragina Maria Antonietta Massucci 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(2):161-170
X-ray photoelectron spectroscopy provides evidence that when [Cu(phen)2]2+(phen = 1,10-phenanthroline) is diffused between the layers of -zirconium phosphate, the complex species does not remain intact after intercalation, but some Cu-N bonds are broken, replaced with Cu-O bonds and the released nitrogen atoms can now interact with the PO3-OH groups of the host. XPS also provides evidence for coordination of the Cu2+ ions when they are diffused by ion exchange in the phenanthroline--zirconium phosphate intercalation compound. Although Cu2+ and phen are in a 1 : 1 molar ratio in the interlayer region of the host, so that a 1 : 1 coordination could be expected between the two species, the characteristic peaks of the uncoordinated phenanthroline, even though at a low intensity, are still present. The differences between the two Cu(II)-intercalation compounds are discussed. 相似文献
115.
A seven-step synthesis ofS-(+)-hydroprene (S-1) in 20 % overall yield starting fromS-(+)-3,7-dimethyl-1,6-octadiene (2) of 55+-10 % optical purity is described. The introduction of an optical enhancement step in the synthetic sequence at the stage ofS-(–)-3,7-dimethyl-1-octanol (9) raises the optical purity ofS-1 from 50 % to 80 %.For part 13, see. ref.1
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–348, February, 1993. 相似文献
116.
L. M. Likhosherstov O. S. Novikova A. O. Zheltova V. N. Shibaev 《Russian Chemical Bulletin》2004,53(3):709-713
An improved procedure for the synthesis of N-bromoacetyl--glycopyranosylamines from the corresponding -glycosylamines was developed. The procedure is applicable to a wide range of derivatives of monosaccharides (hexoses, 2-acetamido-2-deoxyhexoses, hexuronamides, and 6-deoxyhexoses) and some disaccharides. For the derivatives of pentoses and 2-deoxyhexoses, the use of the corresponding -glycosylammonium carbamates was found to be more convenient. N-Bromoacetyl--glycopyranosylamines derived from D-mannose, L-rhamnose, D-glucuronamide, 2-deoxy-D-arabino-hexose, 2-deoxy-D-lyxo-hexose, and melibiose were obtained for the first time. 相似文献
117.
L. V. Rybin S. V. Osintseva A. S. Batsanov Yu. T. Struchkov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1993,42(7):1228-1235
The thermal reactions of Ru3(CO)12 with RCOCH=CHPh (R=Me, p-MeC6H4) in hydrocarbon solvents lead to the formation of a series of complexes, several of which have been isolated as individual compounds by chromatography. The dinuclear complex Ru2(-H)(CO)6(-MeCOCH=CPh) and the tetranuclear complex Ru4(-H)(-CO)(CO)7(p-MeC
6H4 COCH=CPh)(-p-MeC6H4COCH=CPh)(4-p-MeC6H3COCH=CHPh) are characterized by an X-ray structural study. The structures of other reaction products are discussed on the basis of spectral data. The reactions are accompanied by reduction of the starting enones to the corresponding unsaturated ketones.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1293, July, 1993. 相似文献
118.
Preparation of the Iminium Salts CF3? NX?CF2+MF6? (X = CH3, F and M = As, Sb) and CF3? NCl?CF2+ AsF6? The preparation of the iminiumsalts CF3? NX?CF2+ MF6? (X = CH3, F and M = As, Sb) and CF3? NCl?CF2+ AsF6? is reported. The salts were characterized by NMR and infrared spectroscopy. CF3? NCH3?CF2+MF6? decompose into MF5 and (CF3)2NCH3. 相似文献
119.
120.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(11):1155-1161
A new turn on fluorescent probe for ferric ion based on poly(m‐phenyleneethynylene salicylaldimine) ( PPE‐IM ) has been developed. The preparation of PPE‐IM involves post‐polymerization functionalization of the corresponding polymeric amine, PPE‐AM , via the condensation with salicylaldehyde. The degree of polymerization of both PPE‐IM and PPE‐IM is 17 with polydispersity index of 1.5. In aqueous solution, the polymeric PPE‐IM is highly stable unlike its small molecule analog which is gradually hydrolyzed. The weak fluorescence of initial PPE ‐ IM (λem = 470) is greatly enhanced by 300 folds upon the addition of Fe3+. The 1H NMR reveals that the fluorescence enhancement is caused by Fe3+‐induced hydrolysis of the imine group. The sensing system shows a detection limit of 0.14 μM of Fe3+. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1155–1161 相似文献