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61.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Aoki K Aphecetche L Armendariz R Aronson SH Asai J Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Baksay G Baksay L Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bazilevsky A Belikov S Bennett R Berdnikov Y Bickley AA Boissevain JG Borel H Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Campbell S Chang BS Charvet JL Chernichenko S Chiba J Chi CY Chiu M Choi IJ Chujo T Chung P 《Physical review letters》2007,98(23):232002
J/psi production in p+p collisions at square root s=200 GeV has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider over a rapidity range of -2.2相似文献
62.
Adcox K Adler SS Ajitanand NN Akiba Y Alexander J Aphecetche L Arai Y Aronson SH Averbeck R Awes TC Barish KN Barnes PD Barrette J Bassalleck B Bathe S Baublis V Bazilevsky A Belikov S Bellaiche FG Belyaev ST Bennett MJ Berdnikov Y Botelho S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy J Butsyk S Carey TA Chand P Chang J Chang WC Chavez LL Chernichenko S Chi CY Chiba J Chiu M Choudhury RK Christ T Chujo T Chung MS Chung P Cianciolo V Cole BA D'Enterria DG 《Physical review letters》2001,86(16):3500-3505
We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at square root of [s(NN)] = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta(vertical line eta = 0) = 622+/-1(stat)+/-41(syst). The results, analyzed as a function of centrality, show a steady rise of the particle density per participating nucleon with centrality. 相似文献
63.
A new synthesis of 2,3-dialkyl-4-carbomethoxyisoquinolin-1(2H)-ones and 6,7-dialkyl-8-carbomethoxy-1,6-naphthyridin-5(6H)-ones is reported. The process involves treatment of a β-enaminoester with 2-fluoro-5-nitrobenzoyl chloride, 2-fluorobenzoyl chloride or 2-chloronicotinoyl chloride followed by heating in the presence of base. The conversion, which proceeds by an N-acylation-SNAr reaction sequence, affords 50–86% yields when R1 is n-alkyl but ≤30% yields when R1 is α-branched. 相似文献
64.
65.
The main result is a representation theorem which shows that, for a large class of quantum logics, a quantum logic,Q, is isomorphic to the lattice of projective faces in a suitable convex setK. As an application we extend our earlier results [4], which, subject to countability conditions, gave a geometric characterization of those quantum logics which are isomorphic to the projection lattice of a von Neumann algebra or aJ B W-algebra. 相似文献
66.
We report a search for Λ0 polarization in inclusive production by 24 GeV protons on platinum made on data taken at CERN. These data show Λ0 polarization of the same direction and magnitude and with the same pT dependence as found at 300 GeV at Fermilab. 相似文献
67.
Richard A. Bunce Derrick M. Herron Jason R. Lewis Sharadsrikar V. Kotturi 《Journal of heterocyclic chemistry》2003,40(1):113-120
N‐Phenyl‐substituted pyrrolidines and piperidines have been synthesized by catalytic reduction of nitrobenzene in the presence of 4‐ and 5‐oxoaldehydes, respectively. The process involves reduction of the aromatic nitro group to give the N‐phenylhydroxylamine or aniline followed by reductive amination with the two carbonyl functional groups. Monocyclic systems are generally formed in high yield and are easily purified. The method has also been extended to the synthesis of fused N‐phenylazabicyclics from 2‐(3‐oxo‐propyl)cycloalkanones. A high degree of diastereoselectivity for the trans‐fused product is observed in substrates having an ester group α to the cycloalkanone carbonyl. Bicyclic precursors lacking this ester group give mixtures of cis and trans products. Finally, contrary to previous reports, we have demonstrated that aniline can be substituted for nitrobenzene in these reactions. 相似文献
68.
Caignan GA Deshmukh R Zeng Y Wilks A Bunce RA Rivera M 《Journal of the American Chemical Society》2003,125(39):11842-11852
13C NMR spectroscopic studies have been conducted with the hydroxide complex of Pseudomonas aeruginosa heme oxygenase (Fe(III)-OH), where OH(-) has been used as a model of the OOH(-) ligand to gain insights regarding the elusive ferric hydroperoxide (Fe(III)-OOH) intermediate in heme catabolism at ambient temperatures. Analysis of the heme core carbon resonances revealed that the coordination of hydroxide in the distal site of the enzyme results in the formation of at least three populations of Fe(III)-OH complexes with distinct electronic configurations and nonplanar ring distortions that are in slow exchange relative to the NMR time scale. The most abundant population exhibits a spin crossover between S = (1)/(2) and S = (3)/(2) spin states, and the two less abundant populations exhibit pure, S = (3)/(2) and S = (1)/(2), (d(xy)())(1) electronic configurations. We propose that the highly organized network of water molecules in the distal pocket of heme oxygenase, by virtue of donating a hydrogen bond to the coordinated hydroxide ligand, lowers its ligand field strength, thereby increasing the field strength of the porphyrin (equatorial) ligand, which results in nonplanar deformations of the macrocycle. This tendency to deform from planarity, which is imparted by the ligand field strength of the coordinated OH(-), is likely reinforced by the flexibility of the distal pocket in HO. These findings suggest that if the ligand field strength of the coordinated OOH(-) in heme oxygenase is modulated in a similar manner, the resultant large spin density at the meso carbons and nonplanar deformations of the pophyrin ring prime the macrocycle to actively participate in its own hydroxylation. 相似文献
69.
Adler SS Afanasiev S Aidala C Ajitanand NN Akiba Y Alexander J Amirikas R Aphecetche L Aronson SH Averbeck R Awes TC Azmoun R Babintsev V Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Berdnikov Y Bhagavatula S Boissevain JG Borel H Borenstein S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Camard X Chai JS Chand P Chang WC Chernichenko S Chi CY Chiba J Chiu M Choi IJ Choi J Choudhury RK 《Physical review letters》2005,95(20):202001
70.
Amberlyst-15 has been used to catalyze regioselective additions of phenols to α,β-unsaturated ketones in yields of 20–90%. The reaction is superior to the analogous reaction employing concentrated sulfuric acid in affording greater yields and purer products with a minimum of laboratory operations. 相似文献