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201.
Navjeet Kaur 《合成通讯》2018,48(11):1259-1284
The chemists have been interested in light as an energy source to induce chemical reactions since the beginning of scientific chemistry. This review summarizes the chemistry of photochemical reactions with emphasis of their synthetic applications. The organic photochemical reactions avoid the polluting or toxic reagents and therefore offer perspectives for sustainable processes and green chemistry. In summary, this review article describes the synthesis of a number of five-membered N-heterocycles. 相似文献
202.
Navjeet Kaur 《合成通讯》2018,48(17):2119-2149
Photochemical mediated synthesis in organic chemistry is a highly expanding area. This is a widely exploited area of research for the construction of new pharmaceutically significant heterocycles. Recently many reports appeared for the synthesis of heterocycles photochemically due to a wide range of biological activities associated with them. In this article, I have described the synthesis of a number of oxygen-bearing five-membered heterocycles. 相似文献
203.
204.
Boronic acids are important intermediates and molecular recognition moieties in a wide variety of applications. In our research, we have found that the synthesis of ortho-substituted arylboronic acids is problematic with the commonly used bis(pinacolato)diboron in palladium-mediated borylation reactions. As a substitute, we have found that bis(neopentyl glycolato)diboron is a much more efficient borylation agent for the synthesis of sterically hindered ortho-substituted arylboronic acids. 相似文献
205.
Indium mediated allylation, crotylation and cinnamylation of benzoins and its substituted derivatives in THF-H2O (2/1) provide a range of homoallylic alcohols. In general, the benzoins undergo allylation and crotylation in a sluggish manner compared to those observed earlier in the case of α-hydroxy aldehydes and are significantly affected by the electronic features of both the benzoin and indium organometallic reagent. The reactions exhibit higher order of diastereoselectivities than those observed for α-hydroxy aldehydes. The cinnamylation though proceeds in a highly diastereoselective manner but is restricted to only benzoin and 4,4′-dichlorobenzoin. The homoallylic alcohols undergo I2 mediated intramolecular diastereoselective cyclization to provide 2,3-diphenyltetrahydrofuran derivatives. The relative stereochemistries in tetrahydrofurans and homoallylic alcohols have been assigned by coupling constants, NOE experiments and in one case by X-ray crystallography. 相似文献
206.
A non-local core pseudopotential has been used in the framework of floating spherical Gaussian orbital (FSGO ) model to study the equilibrium geometries and valence electronic structures of some organolithium and organoberyllium systems. The calculated equilibrium geometries, heats of hydrogenation, average electric polarizabilities, and magnetic susceptibilities are in good agreement with the results of the all-electron FSGO model calculations. Valence electron wave functions obtained here have been used to predict the valence electron Compton profiles (CP ) and electron momentum distributions (EMD ) of the systems studied. A good correlation has been shown among the peak height of the CP (J(0)), valence electron energy (Ev), and number of valence electrons (Nv). 相似文献
207.
Randhawa B. S. Chhabra D. K. Kaur Sandeep 《Journal of Radioanalytical and Nuclear Chemistry》1986,107(1):49-58
Journal of Radioanalytical and Nuclear Chemistry - The thermal decomposition of sodium hexa-carboxylato/ferrates/III/ i.e. Na3[Fe/RCOO/6].xH2O /R=H, CH3, C2H5/ has been studied at various... 相似文献
208.
Bhanja R Joseph R Tuli SK Beri SB Bhatia VS Kaur G Kaur M Mittra IS Bhalla KB Bharti A Lokanathan S Gupta SK Gupta VK Kaul GL Kumar V Mangotra LK Prakash Y Rao NK Sankhydhar S Satti S Claesson G Garpman S Herrström NY Jakobsson B Lund I Norén B Oskarsson A Otterlund I Persson S Sherif MM Söderström K 《Physical review letters》1985,54(8):771-774
209.
Kaur Paramjit Ballester Loreto Parmar Swarn Singh Singh Kamaljit 《Transition Metal Chemistry》1998,23(5):573-576
The reaction of the CuCl2·2H2O with the N,S donor ligands bis(o-aminobenzenethio)ethane, bis(o-aminoben-zenethio)propane and bis(o-aminobenzenethio)butane (abbreviated as eN2S2, pN2S2 and bN2S2, respectively) yielded mononuclear CuII complexes of stoichiometry Cu(L)Cl2 (L=eN2S2, pN2S2 or bN2S2). When the reactions were performed in the presence of 2,6–diacetylpyridine and NaClO4, binuclear mixed valence CuI–CuII complexes of stoichiometry [Cu2(L)][ClO4]3 (L=eN6S4, pN6S4 or bN6S4) were formed. Metatheses between the binuclear complexes and the lithium salt of 7,7,8,8-tetracyanoquinodimethane (TCNQ) yielded complexes of stoichiometry Cu2(L)(TCNQ)2 (L=eN6S4, pN6S4 or bN6S4). All of the complexes were characterised by analytical and spectroscopic techniques. 相似文献
210.