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111.
John J. Benedetto Rodney Kerby 《Journal of Mathematical Analysis and Applications》2003,279(2):740-755
Wiener's generalized harmonic analysis (GHA) provides a theory of harmonic analysis for subspaces of tempered functions not accessible to the L1,L2, and Fourier series theories; and it does it in a way that is usually more quantitative than that provided by the theory of distributions. On the other hand, GHA does not yield an adequate spectral analysis of large classes of functions, including nonstationary processes and, in particular, 1/f noise. In this paper we adapt GHA to deal with 1/f noise by extending the Wiener-Wintner theorem to the case of 1/f power spectra. 相似文献
112.
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114.
Anna Atlante Salvatore Passarella Giuliana Moreno Christian Salet 《Photochemistry and photobiology》1992,56(4):471-478
Isolated rat liver mitochondria have been used to study the mechanism of toxicity of Rhodamine 123 (Rho 123) in the dark and after irradiation with visible light. We report an inhibition of adenosine 5'-diphosphate phosphorylation which is increased after illumination. In the dark, the first steps of the phosphorylation process (i.e. the entry of substrates into the matrix, the electron transport to oxygen and the creation of the proton gradient) as well as ATPase activity are not significantly perturbed at Rho 123 concentration below 10 micrograms/mL. In contrast, the movements of the phosphate compounds are drastically impaired. Irradiation strengthens the detrimental effects in an oxygen dependent process. The nature of the noxious transient species is not clearly established, but it is suggested that singlet oxygen could be responsible for the observed damage. 相似文献
115.
116.
Eliano Diana Giuliana Gervasio Domenica Marabello Rosanna Rossetti 《Journal of Cluster Science》1998,9(3):223-242
Co2(CO)8 and Te2O react to form the well known Co4(CO)10Te2, Co4(CO)11Te2 complexes and the two new cluster complexes CCo6(CO)12Te2(1), and CCo6(CO)10Te2(Te3) (2). The structures of 1 and 2 were determined by X-ray analysis, together with the triphenylphosphine derivative of 1, CCo6(CO)11(PPh3)Te2(3), which was analyzed to clarify the disordered structure of the parent compound. Complex 1 is formed by a prismatic cluster of cobalt atoms with a carbon embedded in the cage; two tellurium atoms cap the triangular faces of the prism and each cobalt atom links two terminal carbonyl groups. The complex 2 has a similar prismatic cage CCo6; two 4-Te atoms cap two rectangular faces of the prism, while other two Te atoms bridge two edges of the triangular faces and are linked each other through a third Te atom. Electron counting gives for complex 2 92 electrons: the presence of two long Co–Co distances suggests that the two excess electrons are located on Co–Co antibonding orbitals. Crystal data for 1, space group C2/c, a = 12.845(2) Å, b = 13.449(2) Å, c = 13.246(2) Å, = 91.95(2)°, Z = 4, R = 0.097 for 2555 reflections; for 2, space group Pnna, a = 17.219(5) Å, b= 14.969(6) Å, c = 9.178(4) Å, Z = 4,R = 0.037 for 3103 reflections; for 3, space group P21/c, a = 9.288(2) Å, b = 14.920(6) Å, c = 26.300(9) Å, = 99.99(2)°, Z = 4, R = 0.037 for 4300 reflections. The vibrational analysis of the complex 1 was performed and most of the (CO), (6C–Co), (Co–Co) and (Co–Co) modes were assigned. The (Co–Te) modes were interpreted on the basis of the intermolecular coupling, due to the close contact between neighboring clusters in one distinct direction in the crystal. 相似文献
117.
Giuliana Biagi Irene Giorgi Oreste Livi Valerio Scartoni Silvia Velo Antonio Lucacchini Generoso Senatore Pier Luigi Barili 《Journal of heterocyclic chemistry》1995,32(1):169-176
Several new 1,2,3-triazolo[4,5-b][1,4]diazepines were prepared starting from 1-benzyl-1 and 1-phenethyl-4,5-diamino-1,2,3-triazole 2 (Scheme 1), by condensation reactions with β-diketones (Scheme 2), β-ketoesters (Scheme 3), and diethyl malonates (Scheme 4). In the first case we obtained compounds 3 and 4 with basic properties, while the ester function condensations gave cyclic amide derivatives 7, 8, 10, 12 and 13 with acid properties. Some N-methyl derivatives 11, 14 and 15 were obtained from the cyclic amide compounds. Most of compounds were tested for their ability to displace [3H]flunitrazepam from bovine brain membranes but no compound showed benzodiazepine receptor binding affinity. 相似文献
118.
Giuliana Biagi Irene Giorgi Oreste Livi Antonio Nardi Valerio Scartoni 《Journal of heterocyclic chemistry》2002,39(6):1293-1298
Four new triazolylbenzimidazolthione derivatives (2a‐d), analogous to triazolylbenzimidazolone derivatives previously tested as activators of the BKCa potassium channels, were prepared and assayed without success. Some derivatives of a new tricyclic nitrogen heterocycle, 1,2,3‐triazolo[1,5‐a][1,3,5]benzo‐triazepine, bearing a carboxamido group in the 3 position, other substituents in the 8 position and a carbonyl (5a‐d) or thione (6a‐c) or methylthio (7a‐c) function in the 5 position were synthesised. The nucleophilic displacement of the methylthio substituent with morpholine or cyclopentylamine provided the 5‐amino‐substituted tricyclic derivatives 8a‐d. Starting from the l‐(2‐nitrophenyl)‐4‐cyano‐5‐amino‐1,2,3‐triazole (9), the 3‐cyano‐triazolobenzotriazepin‐5‐one derivative 12 was also obtained. The majority of the new compounds were tested towards the BKCa potassium channels, the benzodiazepine and adenosine A1 and A2a receptors, but no remarkable activity was detected. 相似文献
119.
Marzio Cassandro Francesco Nicolò Benedetto Scoppola 《Communications in Mathematical Physics》1989,122(4):681-702
In this paper and its companion (II) we prove that the SupersymmetricN=1 massless Sine-Gordon field theory, at finite (space) volume, exists and is analytic in the coupling constant . Moreover at finite (space) volume is Witten index is=1. 相似文献
120.
Söldner FX McCormick K Eckhartt D Kornherr M Leuterer F Bartiromo R Becker G Bosch HS Brocken H Derfler H Eberhagen A Fussmann G Gehre O Gernhardt J Gierke Gv Giuliana A Glock E Gruber O Haas G Hesse M Hofmann J Izvozchikov A Janeschitz G Karger F Keilhacker M Klüber O Lackner K Lenoci M Lisitano G Mast F Mayer HM Meisel D Mertens V Müller ER Münich M Murmann H Niedermeyer H Pietrzyk A Poschenrieder W Rapp H Riedler H Röhr H Ryter F Schmitter KH Schneider F Setzensack C Siller G Smeulders P 《Physical review letters》1986,57(9):1137-1140