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1.
Albrecht H Binder U Harder G Lembke-Koppitz I Philipp A Schmidt-Parzefall W Schröder H Schulz HD Wurth R Donker JP Drescher A Matthiesen U Scheck H Spaan B Spengler J Wegener aD Gabriel JC Schubert KR Stiewe J Waldi R Weseler S Brown NN Edwards KW Frisken WR Fukunaga C Gilkinson DJ Gingrich DM Goddard M Kapitza H Kim PC Kutschke R MacFarlane DB McKenna JA McLean KW Nilsson AW Orr RS Padley P Patel PM Prentice JD Seywerd HC Stacey BJ Yoon T Yun JC Ammar R Coppage D Davis R Kanekal S Kwak N 《Physical review letters》1986,56(6):549-552
2.
CrIII Phthalocyaninates: Synthesis, Properties, and Crystal Structure of l-Bis(triphenylphosphine)iminium trans-Di(nitrito(O))phthalocyaninato(2–)chromate(III) [Cr(H2O)2Pc2?]Ix reacts with excess (PNP)NO2 in dimethylformamide to yield less soluble greenblack l-bis(triphenylphosphine)iminium trans-di(nitrito(O))phthalocyaninato(2–)chromate(III), l(PNP)trans[Cr(ONO)2Pc2?], which crystallizes in the triclinic space group P1 (No. 2) with Z = 2. The Cr atom is in the center of the Pc2? ligand and the two nitrite ions are monodentate O-coordinated in a mutually trans arrangement to the Cr atom. The Cr? O and Cr? Niso bond distances are 1.9898(14) und 1.981(2) Å, respectively. The geometric data of the coordinated nitrite ion are: d(N? O) = 1.307(2) Å; d(N? O) = 1.205(2) Å; ?(O? N? O) = 113.7(2)°; ?(Cr? O? N) = 116.85(12)°. The non-bonding O atoms are trans to the Cr atom. The Pc2? ligand is slightly saddled. Three weak spin-allowed trip-quartet(TQ) transitions (in 103 cm?1): TQ1 (8.20) < TQ2 (11.3) < TQ3 (20.33) and the characteristic π-π* transitions of the Pc2? ligand: B (14.68) < Q1 (27.1) < Q2 (29.0) < N (35.4) are observed in the UV-VIS-NIR spectrum. Prominent luminescence spectra are obtained by excitation within the TQ1 region, in which the spin-forbidden trip-sextet transition at 7376 cm?1 dominates at low temperatures (T < 50 K). The vibrational spectra are discussed. In coincidence of the excitation lines with TQ3, vs(Cr? O) at 378 cm?1 is selectively resonance Raman (RR) enhanced. vas(Cr? O) is observed in the FIR spectrum at 391 cm?1. The following internal vibrations (in cm?1) of the nitrito ligand are in the MIR spectrum: vas(N? O)/1447 > vas(N? O)/1018/1029 > δ(O? N? O)/828 and in the RR-spectrum: vs(N? O)/1410 > vs(N? O)/952, the last followed by three overtones. 相似文献
3.
Coupling between P and (N)? H has been observed in the 1H{14N}NMR spectra of a series of phosphorus substituted thioformamides, R12/P(X)C(S)NHR2. For R2 = H one of the two couplings constants 3J(PCNH) is much larger than the other. The larger constant is assumed to be 3J(PCNH) (trans) and the magnitude of 3J(PCNH) for several compounds with R2 = Me or Ph is used to assign the configuration about the C(S)? N bond. 相似文献
4.
5.
Molar volumes, V, and compactness values, α, of 34 glassy compositions of the GeSeFe system have been obtained using their
measured densities. The property–composition dependences are examined in light of the models proposed for the structure of
these network glasses.
Received: 28 August 2000 / Accepted: 9 January 2001 / Published online: 23 March 2001 相似文献
6.
D. Heins R. D. Kohaupt W. Kriens M. Leneke K. -H. Matthiesen H. Musfeldt S. Pätzold 《Zeitschrift fur Physik C Particles and Fields》1987,37(1):165-169
A new damping mechanism of multi-bunch oscillations in a storage ring with help of a narrow-band feedback system has been experimentally tested in PETRA. The oscillations of a multi-bunch filling were sucessfully damped. The bandwidth of the active loop was 1.5 kHz instead of 5 MHz needed for standard damper systems. 相似文献
7.
Svend Brodersen 《Journal of Molecular Spectroscopy》2003,219(2):248-257
A new incoherent vibration-rotational Raman spectrum of 16O2 recorded by means of an interferometer is presented. The measured wavenumbers are analyzed together with a coherent Raman spectrum, six different microwave spectra from the vibrational ground state, and one microwave spectrum from the first vibrationally excited state in one fit. Due to the non-linear energy expression for oxygen, such an analysis requires the use of an iteration to find the minimum for the so-called merit function. A method has been developed to secure a stable iteration. The energy expression originally contains 21 constants. A systematic search leads to a reduction of this to 19 constants to make the fit possible. This results in two solutions, which are, however, only two different ways of indicating the one final energy function. The systematic use of iterations reduces the influence of the computational uncertainty on the final molecular constants to be orders of magnitude lower than the uncertainty due to the experimental errors. 相似文献
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10.
For two‐phase flow models, upwind schemes are most often difficult do derive, and expensive to use. Centred schemes, on the other hand, are simple, but more dissipative. The recently proposed multi‐stage (MUSTA ) method is aimed at coming close to the accuracy of upwind schemes while retaining the simplicity of centred schemes. So far, the MUSTA approach has been shown to work well for the Euler equations of inviscid, compressible single‐phase flow. In this work, we explore the MUSTA scheme for a more complex system of equations: the drift‐flux model, which describes one‐dimensional two‐phase flow where the motions of the phases are strongly coupled. As the number of stages is increased, the results of the MUSTA scheme approach those of the Roe method. The good results of the MUSTA scheme are dependent on the use of a large‐enough local grid. Hence, the main benefit of the MUSTA scheme is its simplicity, rather than CPU ‐time savings. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献