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141.
Lafond A Cody JA Souilah M Guillot-Deudon C Kiebach R Bensch W 《Inorganic chemistry》2007,46(4):1502-1506
The study of the pseudobinary system Cu(2)SnS(3-)Cu(2)SiS(3) shows that a solid solution (Cu(2)Si(x)Sn(1-x)S(3)) exists in the range 0.4 < or = Si/(Sn+Si) < or = 0.6. Based on diffuse reflectance and photoelectrochemical measurements these compounds show potential as absorber materials for photovoltaic devices. The compounds were prepared at 850 degrees C from copper sulfide, silicon, tin, and sulfur and were analyzed with single-crystal (for x approximately 0.40) and powder diffraction techniques. Optical band gaps of 1.25, 1.35, and 1.45 eV were observed for the three compositions x = 0.39, 0.48, and 0.61; cathodic photocurrent occurring is significant. 相似文献
142.
Dr. Phil Liebing Dr. Cody Ross Pitts Marc Reimann Dr. Nils Trapp Dr. David Rombach Dustin Bornemann Prof. Dr. Martin Kaupp Prof. Dr. Antonio Togni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):6086-6093
The analysis of crystal structures of SF5- or SF4-containing molecules revealed that these groups are often surrounded by hydrogen or other fluorine atoms. Even though fluorine prefers F⋅⋅⋅H over F⋅⋅⋅F contacts, the latter appeared to be important in many compounds. In a significant number of datasets, the closest F⋅⋅⋅F contacts are below 95 % of the van der Waals distance of two F atoms. Moreover, a number of repeating structural motifs formed by contacts between SF5 groups was identified, including different supramolecular dimers and infinite chains. Among SF4-containing molecules, the study focused on SF4Cl compounds, including the first solid-state structure analyses of these reactive species. Additionally, electrostatic potential surfaces of a series of Ph-SF5 derivatives were calculated, pointing out the substituent influence on the ability of F⋅⋅⋅X contact formation (X=F or other electronegative atom). Interaction energies were calculated for different dimeric arrangements of Ph-SF5, which were extracted from experimental crystal structure determinations. 相似文献
143.
George H. Major Sean C. Chapman Jeffrey T. Chapman Joshua I. Wheeler Shiladitya Chatterjee Cody V. Cushman Daniel H. Ess Matthew R. Linford 《Surface and interface analysis : SIA》2021,53(1):5-13
SU‐8 is an important, epoxy‐based, negative photoresist that can create high aspect ratio features. Spectroscopic ellipsometry (SE) is a nondestructive analytical technique that can be performed in the open air. In this study, reflection and transmission SE measurement data were combined to model the optical function of SU‐8 photoresist. The data were fit using three different models: (i) a B‐spline model, (ii) a four‐Gaussian oscillator model with an ultraviolet (UV) and an infrared (IR) pole, and (iii) a Cody–Lorentz model with three additional Gaussian oscillators. All three models successfully fit the data, where the B‐spline model showed the lowest mean squared error. In situ SE data were also collected and fitted to follow possible changes in the optical properties of the SU‐8 during its development. Time‐dependent density functional theory (TD‐DFT) modeling of a complete SU‐8 monomer is qualitatively and quantitatively consistent with the measured optical function. 相似文献
144.
Cody B. Hyndman Polynice Oyono Ngou 《Methodology and Computing in Applied Probability》2017,19(1):1-29
We propose a new method for the numerical solution of backward stochastic differential equations (BSDEs) which finds its roots in Fourier analysis. The method consists of an Euler time discretization of the BSDE with certain conditional expectations expressed in terms of Fourier transforms and computed using the fast Fourier transform (FFT). The problem of error control is addressed and a local error analysis is provided. We consider the extension of the method to forward-backward stochastic differential equations (FBSDEs) and reflected FBSDEs. Numerical examples are considered from finance demonstrating the performance of the method. 相似文献
145.
Gaussian factor models futures and forward prices 总被引:1,自引:0,他引:1
Email: hyndman{at}mathstat.concordia.ca
Received on 31 July 2006. Accepted on 19 March 2007. We completely characterize the futures price and forward priceof a risky asset (commodity) paying a stochastic dividend yield(convenience yield). The asset (commodity) price is modelledas an exponential affine function of a Gaussian factors process,while the interest rate and dividend yield are affine functionsof the factors process. The characterization we provide is basedon the method of stochastic flows. We believe this method leadsto simpler and more clear-cut derivations of the futures priceand forward price formulae than alternative methods. Hedginga long-term forward contract with shorter term futures contractsand bonds is also examined. 相似文献
146.
Giffin NA Makramalla M Hendsbee AD Robertson KN Sherren C Pye CC Masuda JD Clyburne JA 《Organic & biomolecular chemistry》2011,9(10):3672-3680
In this paper, we report a novel synthesis of anhydrous 1-hydroxy-2,2,6,6-tetramethyl-piperidine (TEMPO-H). An X-ray crystal structure and full characterization of the compound are included. Compared to hydrated TEMPO-H, its anhydrous form exhibits improved stability and a differing chemical reactivity. The reactions of anhydrous TEMPO-H with a variety of low-valent carbon centres are described. For example, anhydrous TEMPO-H was reacted with 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes), an unsaturated NHC. Crystals of [CHNC(6)H(2)(CH(3))(3)](2)C···HO(NC(5)H(6)(CH(3))(4)), IMes···TEMPO-H, were isolated and a crystal structure determined. The experimental structure is compared to the results of theoretical calculations on the hydrogen-bonded dimer. Anhydrous TEMPO-H was also reacted with the saturated NHC, 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene (SIPr), giving the product [CH(2)Ni-Pr(2)C(6)H(3)](2)CH···O(NC(5)H(6)(CH(3))(4)). In contrast, the reaction of hydrated TEMPO-H with 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene gave small amounts of the hydrolysis product, N-(2,6-diisopropylphenyl)-N-[2-(2,6-diisopropylphenylamino)ethyl]formamide. Finally, anhydrous TEMPO-H was reacted with (triphenylphosphoranylidene)ketene to generate Ph(3)PC(H)C(=O)O(NC(5)H(6)(CH(3))(4)). A full characterization of the product, including an X-ray crystal structure, is described. 相似文献
147.
The ground state rotational spectra of 2-fluoropyridine and 3-fluoropyridine have been investigated using both Fourier transform microwave (FTMW) and chirped pulse Fourier transform microwave (cp-FTMW) spectroscopies. In addition to the parent species, the spectra of the (13)C and (15)N singly substituted isotopologues were recorded in the 8-23 GHz region in natural abundance. The rotational constants determined for the seven isotopologues of each were used to calculate relevant geometric parameters including the bond distances and angles of the pyridine ring backbone. The derived structures show a more pronounced deviation from the pyridine ring geometry when the fluorine substituent is ortho to nitrogen which is consistent with ab initio predictions at various levels of theory. Analysis of the (14)N hyperfine structure provided an additional source of information about the electronic structure surrounding the nitrogen atom as a function of fluorine substitution. Together, the experimental results are consistent with a bonding model that involves hyperconjugation whereby fluorine donates electron density from its lone pair into the π-system of pyridine. 相似文献
148.
Sanjay Dutta Sergey M. Dibrov Bao T. Ho Cody J. Higginson Thomas Hermann 《Journal of chemical crystallography》2012,42(2):119-129
Abstract
The compound 5, containing the novel heterocycle 2-oxa-4,7-diazabicyclo[3.3.1]non-3-ene, has been obtained in a synthetic approach toward oxazoles and 1,3-diazepanes of natural product-like complexity from cyclization and rearrangement of δ-lactam cyanamides. When this procedure was applied to a silyl-protected N-((3S,4S,5S)-4,5-dihydroxy-2-oxopiperidin-3-yl)cyanamide (2b) formation of the novel heterobicyclic scaffold 5 was observed along with the expected oxazole (3b) and diazepane (4b) products. The crystal structures of 5 and diazepane 4b are described. Compound 5 crystallized from methanol in the monoclinic system, P21 space group with unit cell parameters a = 15.3402(9), b = 7.2717(4), c = 22.5803(13), β = 106.8620(10) and a cell volume of 2410.5(2) A3. 相似文献149.
Cody Blaine Hyndman 《Mathematics and Financial Economics》2009,2(2):107-128
We consider factor models for interest rates and asset prices where the risk- neutral dynamics of the factors process is modelled
by an affine diffusion. We characterize the factors process and bond price in terms of forward–backward stochastic differential
equations (FBSDEs), prove an existence and uniqueness theorem which gives the solution explicitly, and characterize the bond
price as an exponential affine function of the factors in a new way. Our approach unifies the results, based on stochastic
flows, of Elliott and van der Hoek (Finance Stoch 5:511–525, 2001) with the approach, based on the Feynman-Kac formula, of
Duffie and Kan (Math Finance 6(4):379–406, 1996), and addresses a mistake in the approach of Elliott and van der Hoek (Finance
Stoch 5:511–525, 2001). We extend our results on the bond price to consider the futures and forward price of a risky asset
or commodity.
相似文献
150.
T. Seki I. Sugai Y. Hasegawa S. Mitani K. Takanashi 《Solid State Communications》2010,150(11-12):496-499
The spin-Hall effect and the Nernst effect were investigated in multi-terminal devices consisting of an FePt perpendicular spin polarizer and a Au Hall cross with different Au thicknesses. As the thickness of the Au Hall cross increased from 10 nm to 20 nm, the spin-Hall angle () was significantly reduced. The significant reduction of the spin-Hall angle indicates that the interface and/or surface scattering of the electron spins play a crucial role for the large . The voltage change due to the Nernst effect also decreased with increasing the thickness of the Au Hall cross. 相似文献