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61.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Areti H Auchincloss P Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bartalini P Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bolognesi V Bortoletto D Boswell C Boulos T Brandenburg G Buckley-Geer E Budd HS Burkett K 《Physical review letters》1994,72(22):3456-3460
62.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Areti H Auchincloss P Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bartalini P Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bolognesi V Bortoletto D Boswell C Boulos T Brandenburg G Buckley-Geer E Budd HS Burkett K 《Physical review letters》1994,72(19):3004-3008
63.
Jingbai Li Patrick Reiser Benjamin R. Boswell Andr Eberhard Noah Z. Burns Pascal Friederich Steven A. Lopez 《Chemical science》2021,12(14):5302
Photochemical reactions are widely used by academic and industrial researchers to construct complex molecular architectures via mechanisms that often require harsh reaction conditions. Photodynamics simulations provide time-resolved snapshots of molecular excited-state structures required to understand and predict reactivities and chemoselectivities. Molecular excited-states are often nearly degenerate and require computationally intensive multiconfigurational quantum mechanical methods, especially at conical intersections. Non-adiabatic molecular dynamics require thousands of these computations per trajectory, which limits simulations to ∼1 picosecond for most organic photochemical reactions. Westermayr et al. recently introduced a neural-network-based method to accelerate the predictions of electronic properties and pushed the simulation limit to 1 ns for the model system, methylenimmonium cation (CH2NH2+). We have adapted this methodology to develop the Python-based, Python Rapid Artificial Intelligence Ab Initio Molecular Dynamics (PyRAI2MD) software for the cis–trans isomerization of trans-hexafluoro-2-butene and the 4π-electrocyclic ring-closing of a norbornyl hexacyclodiene. We performed a 10 ns simulation for trans-hexafluoro-2-butene in just 2 days. The same simulation would take approximately 58 years with traditional multiconfigurational photodynamics simulations. We generated training data by combining Wigner sampling, geometrical interpolations, and short-time quantum chemical trajectories to adaptively sample sparse data regions along reaction coordinates. The final data set of the cis–trans isomerization and the 4π-electrocyclic ring-closing model has 6207 and 6267 data points, respectively. The training errors in energy using feedforward neural networks achieved chemical accuracy (0.023–0.032 eV). The neural network photodynamics simulations of trans-hexafluoro-2-butene agree with the quantum chemical calculations showing the formation of the cis-product and reactive carbene intermediate. The neural network trajectories of the norbornyl cyclohexadiene corroborate the low-yielding syn-product, which was absent in the quantum chemical trajectories, and revealed subsequent thermal reactions in 1 ns.Photochemical reactions are widely used by academia and industry to construct complex molecular architectures via mechanisms that are often inaccessible by other means. 相似文献
64.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Bacchetta N Baden AR 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 letters》1993,71(5):679-683
65.
Abe F Albrow M Akimoto H Amidei D Anway-Wiese C Apollinari G Areti H Auchincloss P Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J 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 Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bolognesi V Bortoletto D Boswell C Boulos T Brandenburg G Bromberg C Buckley-Geer E Budd HS 《Physical review letters》1993,71(16):2542-2546
66.
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 letters》1993,70(15):2232-2236
67.
G. Evan Boswell Robert W. Mcnutt Dulce G. Bubacz Ann O. Davis Kwen-Jen Chang 《Journal of heterocyclic chemistry》1995,32(6):1801-1818
The synthesis of a series of heterocyclic analogues of (±)-4-((αR*)-α-((2S*,5R*)-4-allyl-2,5-dimethyl-1-piperazmyl)-3-hydroxybenzyl)-N,N-diethylbenzarrude (BW373U86) for screening against opioid receptors is described. The intermediate α-heterocyclic benzyl alcohols 24 were synthesized either by low temperature reaction of lithioheterocycles with 3-((tert-butyldimethylsilyl)oxy)benzaldehyde ( 10 ) or by reaction of 3-((tert-butyldimethylsilyl)oxy)phenylmagnesium bromide ( 19 ) with heterocyclic carbaldehydes. The α-heterocyclic benzyl alcohols 24 were converted to chloromethines ( 25 ) with thionyl chloride and used to alkylate with trans-1-allyl-2,5-dimethylpiperazine ( 5 ) to give diastereomeric pairs of the target compounds. The bromoheterocycles were then derivatized to produce amides. Compounds that are potent and selective for the 5 or μ opioid receptors and some mixed δ/μ analogues are reported. 相似文献
68.
Potentiometric sensors based on fluorous membranes doped with a fluorophilic tetraphenylborate derivative are shown to have a remarkably wide range of selectivities that exceeds the selectivity range of conventional polymeric membranes by 8 orders of magnitude. The fluorous character of these sensing membranes explains the formation of ion pairs of unprecedented strength. Ion pair formation constants in perfluoroperhydrophenanthrene, as measured in this work, are on the order of 1020 and exceed previously reported values for ion pair formation in nonpolar solvents by 6 orders of magnitude. The low solubility of lipids in such fluorous phases makes them very promising for the reduction of biofouling. 相似文献
69.
The dispersion and damping of whistler waves has been measured in an essentially collisionless plasma at frequencies up to 0.92ωc, the electron cyclotron frequency. The experimental results agree to within ± 10% of the plane wave hot plasma dispersion relation. 相似文献
70.
A separation of selenium based on the extraction of different concentrations of Se(IV) from 12 M hydrochloric acid or 8 M hydrobromic acid into toluene is described. Recoveries of 92% and 97%, respectively, are achieved in 7 min. Oxidizing agents interfere. 相似文献