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131.
Aubert B Boutigny D De Bonis I Gaillard JM Jeremie A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Reinertsen PL Stugu B Abbott B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Dardin S Day C Dow SF Elioff T Fan Q Gaponenko I Gill MS Goozen FR Gowdy SJ Gritsan A Groysman Y Jacobsen RG Jared RC Kadel RW Kadyk J Karcher A Kerth LT Kipnis I Kluth S Kolomensky YG Kral JF Lafever R LeClerc C Levi ME Lewis SA 《Physical review letters》2001,86(12):2515-2522
We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta = 0.34+/-0.20 (stat)+/-0.05 (syst). 相似文献
132.
Burkhart DJ McKenzie AR Nelson JK Myers KI Zhao X Magnusson KR Natale NR 《Organic letters》2004,6(8):1285-1288
Utilizing our lateral metalation coupled with Jacobsen's catalytic asymmetric amino nitrile synthesis, we have demonstrated the ability to synthesize isoxazole-containing amino acid glutamate analogues in high yield and high enantiomeric excesses. Chiral centers alpha or beta at the C-5 position do not detract from diastereoselectivity of the Jacobsen-Strecker reaction. [reaction: see text] 相似文献
133.
The synthesis of γ-lactams from both four-component and imine-anhydride reactions is reported. The synthesis of 2-phenylcyclohexanethiol is described and this compound was evaluated along with an additional seven chiral thiols. A range of selectivity and yields was observed and comparisons to established reactions are made in order to account for the observed reactivity. 相似文献
134.
Yueyan Zhang Jared J. Griebel Philip T. Dirlam Ngoc A. Nguyen Richard S. Glass Michael E. Mackay Kookheon Char Jeffrey Pyun 《Journal of polymer science. Part A, Polymer chemistry》2017,55(1):107-116
High sulfur content copolymers were prepared via the inverse vulcanization of elemental sulfur with styrene. This reaction was carried out at a relatively low temperature and invokes a new chain transfer mechanism of abstraction of benzylic protons to form stable copolymers. The use of styrene as a comonomer for inverse vulcanization was attractive due to the low cost and wide spread industrial use of styrenics in free radical processes. The copolymers were used as the active cathode material in Li‐S batteries that exhibited outstanding device performance, maintaining 489 mAh/g capacity after 1000 cycles. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 107–116 相似文献
135.
Electronic Properties of Mono‐Substituted Tetraferrocenyl Porphyrins in Solution and on a Gold Surface: Assessment of the Influencing Factors for Photoelectrochemical Applications 下载免费PDF全文
Dr. Andrea Vecchi Nathan R. Erickson Jared R. Sabin Prof. Barbara Floris Prof. Valeria Conte Prof. Mariano Venanzi Dr. Pierluca Galloni Prof. Victor N. Nemykin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):269-279
Two unsymmetric meso‐tetraferrocenyl‐containing porphyrins of general formula Fc3(FcCOR)Por (Fc=ferrocenyl, R=CH3 or (CH2)5Br, Por=porphyrin) were prepared and characterized by a variety of spectroscopic methods, whereas their redox properties were investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) approaches. The mixed‐valence [Fc3(FcCOR)Por]n+ (n=1,3) were investigated using spectroelectrochemical as well as chemical oxidation methods and corroborated with density functional theory (DFT) calculations. Inter‐valence charge‐transfer (IVCT) transitions in [Fc3(FcCOR)Por]+ were analyzed, and the resulting data matched closely previously reported complexes and were assigned as Robin–Day class II mixed‐valence compounds. Self‐assembled monolayers (SAMs) of a thioacetyl derivative (Fc3(FcCO(CH2)5SCOCH3)Por) were also prepared and characterized. Photoelectrochemical properties of SAMs in different electrolyte systems were investigated by electrochemical techniques and photocurrent generation experiments, showing that the choice of electrolyte is critical for efficiency of redox‐active SAMs. 相似文献
136.
Synthesis,characterization, and photovoltaic properties of dithienylbenzobisazole‐dithienylsilole copolymers 下载免费PDF全文
Achala Bhuwalka Monique D. Ewan Jared F. Mike Moneim Elshobaki Brandon Kobilka Sumit Chaudhary Malika Jeffries‐EL 《Journal of polymer science. Part A, Polymer chemistry》2015,53(13):1533-1540
Three conjugated polymers comprised of dioctyl‐dithieno‐[2,3‐b:2',3'‐d]silole and a donor‐acceptor‐donor triad of either cis‐benzbisoxazole, trans‐benzobisoxazole or trans‐benzobisthiazole were synthesized via the Stille cross‐coupling reaction. The impact of varying the heteroatoms and/or the location within the benzobisazole moiety on the optical and electronic properties of the resulting polymers was evaluated via cyclic voltammetry and UV‐Visible spectroscopy. All of the polymers have similar optical band‐gaps of ~1.9 eV and highest occupied molecular orbital levels of ? 5.2 eV. However, the lowest unoccupied molecular orbitals (LUMO) ranged from ? 3.0 to ? 3.2 eV. Interestingly, when the polymers were used as donor materials in bulk‐heterojunction photovoltaic cells with PC71BM as the electron‐acceptor, the benzobisoxazole‐based polymers gave slightly better results than the benzobisthiazole‐containing polymers with power conversion efficiencies up to 3.5%. These results indicate that benzobisoxazoles are promising materials for use in OPVs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1533–1540 相似文献
137.
138.
Response to the Comment on Paper “Water vapor Enhancement of Rates of Peroxy Radical Reactions”, Int. J. Chem. Kinetics, 47, 395, 2015 下载免费PDF全文
139.
140.
The torque roll axis motion decoupling concept is analytically and computationally studied in a realistic coupled powertrain and frame system using discrete, proportionally damped linear models. Recently, Hu and Singh (2012 [1]) (Journal of Sound and Vibration 331 (2012) 1498–1518) proposed new paradigms to fully decouple such a system. However, critical examination shows that the derivation does not always lead to a physically realizable system, as each powertrain mount is not referenced to a single location. This deficiency is overcome by deriving mount compatibility conditions to ensure realistic mount positions which are incorporated into proposed decoupling conditions. It is mathematically shown that full decoupling is not possible for a practical system, and therefore partial decoupling paradigms are pursued. Powertrain mount design using only the decoupled powertrain achieves better decoupling than minimizing conditions for the coupled system using a total least squares method. Further decoupling is obtained through frame isolation design using a decoupled frame model such that the torque roll mode is dominant over the frequency range considered. Other methods for limiting frame coupling are also briefly discussed. 相似文献