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81.
Chymotrypsin catalysis. Evidence for a new intermediate. 3 总被引:3,自引:0,他引:3
82.
Brown CN Awes TC Beddo ME Brooks ML Bush JD Carey TA Chang TH Cooper WE Gagliardi CA Garvey GT Geesaman DF Hawker EA He XC Isenhower LD Kaplan DM Kaufman SB Kirk PN Koetke DD Kyle G Lee DM Lee WM Leitch MJ Makins N McGaughey PL Moss JM Mueller BA Nord PM Papavassiliou V Park BK Peng JC Petitt G Reimer PE Sadler ME Sondheim WE Stankus PW Thompson TN Towell RS Tribble RE Vasiliev MA Webb JC Willis JL Wise DK Young GR;FNAL E/NuSea Collaboration 《Physical review letters》2001,86(12):2529-2532
We present a measurement of the polarization observed for bottomonium states produced in p-Cu collisions at square root of s = 38.8 GeV. The angular distribution of the decay dimuons of the Upsilon(1S) state shows no polarization at small values of the fractional longitudinal momentum x(F) and transverse momentum p(T) but significant positive transverse production polarization for either p(T)>1.8 GeV/c or for x(F)>0.35. The Upsilon(2S+3S) (unresolved) states show a large transverse production polarization at all values of x(F) and p(T) measured. These observations challenge NRQCD calculations of the polarization expected in the hadronic production of bottomonium states. 相似文献
83.
Inferences made from analysis of BOLD data regarding neural processes are potentially confounded by multiple competing sources: cardiac and respiratory signals, thermal effects, scanner drift, and motion-induced signal intensity changes. To address this problem, we propose deconvolution filtering, a process of systematically deconvolving and reconvolving the BOLD signal via the hemodynamic response function such that the resultant signal is composed of maximally likely neural and neurovascular signals. To test the validity of this approach, we compared the accuracy of BOLD signal variants (i.e., unfiltered, deconvolution filtered, band-pass filtered, and optimized band-pass filtered BOLD signals) in identifying useful properties of highly confounded, simulated BOLD data: (1) reconstructing the true, unconfounded BOLD signal, (2) correlation with the true, unconfounded BOLD signal, and (3) reconstructing the true functional connectivity of a three-node neural system. We also tested this approach by detecting task activation in BOLD data recorded from healthy adolescent girls (control) during an emotion processing task. 相似文献
84.
Sokol Bush Kaliaj 《Mathematische Nachrichten》2014,287(14-15):1701-1709
A generalized bounded variation characterization of Banach spaces possessing the Radon‐Nikodym property is given in terms of the average range. We prove that a Banach space X has the Radon‐Nikodym property if and only if for each function of generalized bounded variation on [0, 1], the average range is a nonempty set at almost all . 相似文献
85.
The vibrational spectra of 1-chloro-1-hydro-F-ethane,CF3CHFCℓ, and 1-bromo-1-hydro-F-ethane,CF3CHFBr
Infrared and Raman spectra were obtained for the fluorinated ethanes, CF3CHFC? and CF3CHFBr, and their deuterated isotopomers. A vibrational assignment of these molecules is reported. 相似文献
86.
Optical activity of n-pi transitions in polynucleotides 总被引:4,自引:0,他引:4
C A Bush 《The Journal of chemical physics》1970,53(9):3522-3530
87.
A procedure for isolating the real roots of an equation is presented. The technique requires only function values and can be applied readily to complicated transcendental functions. A program implementing the technique is provided. 相似文献
88.
89.
B. Bush J. H. Craig Jr. K. R. Roos J. Lozano K. W. Field 《Surface and interface analysis : SIA》2008,40(5):927-930
Ultraviolet photoemission spectra (UPS) are presented for condensed layers of three ethylated amines; mono‐, di‐, and triethylamine (TEA) on the Si(100) surface at 100 K. The photoemission peaks associated with the nitrogen lone pair electrons are identified in the amines and compared with the corresponding spectra for condensed ammonia. Shifts in the lone pair binding energy for the ethyl‐substituted amines are shown to be consistent with conventional chemical paradigms. Also, for comparison purposes spectra for two nonethylated amines, trimethylamine (TMA), and its silicon analog, trisilylamine (TSA), are presented and discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
90.
Infrared laser action spectroscopy is used to characterize divalent calcium ions solvated by up to 69 water molecules. The spectrum for Ca(2+)(H2O)12 indicates that in the predominant structure, eight inner-shell water molecules solvate the metal ion and donate one hydrogen bond to one of four second-shell, double-acceptor water molecules. Eight-coordinate solvation is consistent with results from many condensed-phase studies, and contrasts with results for smaller gas-phase clusters that are most consistent with six-coordinate solvation. Each water molecule in this structure of Ca(2+)(H2O)12 coordinates with two other members of the cluster. With increasing cluster size, the number of two-coordinate water molecules decreases, whereas that of three-coordinate water molecules increases. The number of one-coordinate water molecules increases until n approximately 18, but they are essentially depleted by n approximately = 30. Spectra of the largest clusters, which have effective concentrations of divalent calcium that are less than 1 M, exhibit only subtle changes with increasing cluster size. The bonded-OH regions of these spectra are similar to, but blue-shifted from that of bulk water, whereas the free-OH regions are well-resolved and indicate that the surfaces of these clusters are well-structured. These results comprise the most extensive vibrational spectroscopic study yet performed on metal ion hydration in the gas phase and provide insights into metal ion solvation in bulk and interfacial environments. 相似文献