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51.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bacchetta N Bailey MW Bamberger A Barnett BA Barbaro-Galtieri A Barnes VE Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Castro A Cervelli F Chadwick K 《Physical review letters》1992,68(10):1458-1462
52.
Abe F Amidei D Apollinari G Ascoli G Atac M Auchincloss P Baden AR Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge P Bertolucci S Bhadra S Binkley M Blair R Blocker C Bofill J Booth AW Brandenburg G Brown D Byon A Byrum KL Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chapin T Chiarelli G Chinowsky W Cihangir S Cline D Connor D Contreras M Cooper J Cordelli M Curatolo M Day C DelFabbro R 《Physical review letters》1990,64(4):348-352
53.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review letters》1990,64(2):147-151
54.
Semi-empirical molecular orbital calculations have been carried out on the steroidal hormone estrone, both as a neutral molecule and the corresponding positively charge molecular ion. These calculations provide estimates of bond densities and net atomic charges, factors deemed important in past correlations of observed mass spectra with molecular structure. Calculated net charges appear to be unrelated to fragmentation processes. Calculated bond densities of the ground state molecular ion of estrone allow prediction of gross features of fragmentation. Bond densities of excited electronic states of the molecular ion may provide a basis for finer distinction among sites of initial bond cleavage, which is information crucial to rationalization of subsequent fragmentation of the molecular ion. 相似文献
55.
56.
Abe F Amidei D Apollinari G Ascoli G Atac M Auchincloss P Baden AR Barbaro-Galtieri A Barnes VE Bedeschi F Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge P Bertolucci S Bhadra S Binkley M Blair R Blocker C Bofill J Booth AW Brandenburg G Brown D Byon A Byrum KL Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chapin T Chiarelli G Chinowsky W Cihangir S Cline D Connor D Contreras M Cooper J Cordelli M Curatolo M Day C DelFabbro R 《Physical review D: Particles and fields》1989,40(11):3791-3794
57.
Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Peruzzi I Piccolo M Hurst RB Pyrlik J Venuti JP Weinstein R Gettner MW Goderre GP Sleeman JC von Goeler E Chadwick GB Leedy RE Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Verdini PG Band HR Delfino MC Johnson JR Lavine TL Maruyama T Prepost R 《Physical review D: Particles and fields》1989,40(5):1385-1396
58.
The product formed from cyclopentadiene and the cyclo-octatetraene dimer 5a has been shown to possess structure 6a, probably resulting from Cope rearrangement of an initial adduct 4a. The reaction of tetraphenylcyclopentadienone with 1 - methoxybuta - 1,3 - diene yields a mixture of the exo-adduct 14 and the rearranged endo-adduct 13 Rearrangement of the norbornenone derivative 27 gives the Cope product 29 Treatment of the 4,5-fused 2,3,4,5-tetrachlorocyclopent-2-enones 29,40 and 41 with powdered sodium hydroxide in tetrahydrofuran results in ring-cleaveage with the formation of 2,3,5-trichlorobuta-2,4-dienoic acid derivatives, 36, 43 and 44 respectively. 相似文献
59.
There are numerous methods of preparing nanocrystalline materials. Magnesium oxide is an ideal model system on which to probe the relation of the preparative route and the microstructure. Using X-ray absorption spectroscopy (XAS) we show that the sol-gel route can be used to prepare highly crystalline material provided there is careful control of the calcination conditions. In the present work this is achieved by calcining at high temperatures (at least 800 degrees C). However, this results in grain growth that can be prevented by the addition of a pinning agent, SiO(2), during the preparation of the sol. The pinned samples maintain a particle size of 11 nm even after calcining at 1000 degrees C. Ball-milling is a common method of preparing nanocrystalline oxides, however the present work shows that this produces a significant fraction of amorphous material, the fraction increasing with decreasing grain size (e.g. approximately 30 % for a grain size of 23 nm). 相似文献
60.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A 《Physical review D: Particles and fields》1993,48(9):R3939-R3944