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1.
A simple and efficient synthesis of 2-arachidonoyl glycerol, an endogenous agonist for cannabinoid receptors was achieved using Novozym 435, immobilized lipase from Candida antarctica. 相似文献
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G. Igo G.S. Adams T.S. Bauer G. Pauletta C.A. Whitten A. Wreikat G.W. Hoffmann G.S. Blanpied W.R. Coker C. Harvey R.P. Liljestrand L. Ray J.E. Spencer H.A. Thiessen C. Glashausser N.M. Hintz M.A. Oothoudt H. Nann M. Gazzaly 《Physics letters. [Part B]》1979,81(2):151-155
Differential cross sections and analyzing powers for the elastic scattering of 800 MeV polarized protons from 40,42,44,48Ca are reported. A first-order, spin-dependent KMT optical potential analysis is presented from which the rms radii of the neutron densities are deduced. A comparison of these results with other determinations and with various theoretical predictions is given. 相似文献
5.
D. L. Adams B. Aas E. Bleszynski M. Bleszynski G. Igo C. Newsom Y. Ohashi G. Pauletta F. Sperisen C. A. Whitten Jr. H. Fujisawa M. GazzalyS. J. Greene K. Jones J. B. McClelland N. TanakaH. Hasai K. IwataniS. Ishimoto S. IsagawaA. MasaikeA. OkihanaS. Okumi 《Nuclear Physics A》1988,480(3-4)
We have measured spin correlation parameters that describe the elastic scattering of 800 MeV polarized protons from an L-type polarized deuteron target at laboratory angles below 20°. The measured parameters include the correlated analyzing powers ASL, ALL and ANLL and the proton spin-transfer coefficients C0L,S, C0L,L, CSL,N, CNL,S, CNL,L and CLL,N. The results are compared with single-scattering predictions based on different phase-shift solutions for the nucleon-nucleon scattering matrix. 相似文献
6.
J. Ball C. D. Lac F. Lehar A. de Lesquen L. van Rossum P. Chaumette J. Derégel J. Fabre M. de Mali J. M. Fontaine F. Perrot P. Bach G. Gaillard R. Hess D. Rapin Ph. Sormani V. Ghazikhanian C. A. Whitten R. Peschina E. Rössle 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):193-197
We present the measurements of the spin correlation parameterA ookk (np). A longitudinally polarized beam of free neutrons obtained from the break-up of polarized deuterons was scattered on the longitudinally polarized Saclay frozen-spin proton target. Measurements were carried out at SATURNE II, at neutron beam kinetic energies of 0.63, 0.88, 0.98 and 1.08 GeV. The data points cover the angular region from about 40° to 110° CM. The observed angular dependence ofA ookk (np) at 0.63 GeV agree with the phase shift analysis predictions except at small angles. 相似文献
7.
David Rosenthal Frederick R. Hopf David G. Whitten Maurice M. Bursey 《Journal of mass spectrometry : JMS》1973,7(4):497-499
The ruthenium porphyrin carbonyl (I) reacts with perfluorokerosene and perfluorotributylamine to give ions of the type [M – CO + CnF2n], n = 1 to 4. 相似文献
8.
Differential cross sections for the 208Pb (p, n) reaction populating the isobaric analog state (IAS) of the 208Pb ground state in 208Bi have been measured at a proton bombarding energy of 30.5 MeV. The experimental technique utilized the proton (p?) decay of the IAS to obtain neutron time-of-flight spectra. When these differential cross sections are compared to those obtained for the same reaction at 30.5 MeV using the pulsed-beam technique to obtain neutron time-of-flight spectra, the percentage of the IAS decay through p? channels is obtained. This comparison indicates that the p? decay of the IAS to the first three states of 207Pb accounts for almost all of the IAS width (0.97±0.28). 相似文献
9.
Photochemistry and Photophysical Properties of Novel, Unsymmetrically Substituted Metallophthalocyanines 总被引:1,自引:0,他引:1
Abstract— A series of novel, unsymmetrically substituted metallophthalocyanines was synthesized, along with their symmetrically substituted analogs, and the effects of structure and metal substitution on their photophysical and photoredox properties were investigated. The macrocy-cles were synthesized using a mixed-condensation method followed by chromatographic separation of the resulting soluble products. They possess a catechol "active site" and three tert-butyl groups for enhanced solubility. The ground- and excited-state photophysical properties of the free-base, Zn(II) and Pd(II) macrocycles were measured and compared with their symmetrically substituted (tetra[ tert -butyl]) analogs. The efficiency with which these macrocycles sensitize the formation of singlet oxygen was determined and discussed in the context of the excited-state photophysical properties. Several examples of photoinduced electron transfer reactions with one- and two-electron acceptors are demonstrated and discussed. These soluble molecules can be tuned to optimize their photochemical and redox properties by varying the central metal, axial ligands and other substituents, thereby providing a series of molecules for the investigation of photodynamic therapy and photoinduced electron transfer mechanisms. 相似文献
10.
The chemisorption of H2 on Ti(0001) is treated using an ab initio CI theory for the surface region. Dissociation of H2 occurs above the surface but more stable 3-fold coordination sites lie closer to the surface at ~ 1.3 Å. Adsorption in adjacent 3-fold sites is less stable than in separated sites sharing only one surface atom. The calculated adsorption energy of 45 kcal/mol H2 compares favorably with experiment. Bonding involves mainly the 4s electrons of the metal leading to hydridic hydrogens and a polarized lattice electron distribution, but d bonding and correlation effects significantly increase the binding energy. Calculations on small metal clusters also show dissociative adsorption but much larger hydrogen binding energies are obtained. 相似文献