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71.
72.
P.J. Bussey C. Raine J.G. Rutherglen P.S.L. Booth L.J. Carroll G.R. Court P.R. Daniel A.W. Edwards R. Gamet C.J. Hardwick P.J. Hayman J.R. Holt J.N. Jackson J.H. Norem W.H. Range F.H. Combley W. Galbraith V.H. Rajaratnam C. Sutton 《Nuclear Physics B》1979,154(2):205-225
Measurements have been made of the polarisation parameters Σ, T and P for the process γp → π+n in the photon energy range 520–2250 MeV at c.m. angles between 30° and 120°. These data were obtained in a double polarisation experiment, using the polarised photon beam from the Daresbury electron synchrotron incident on a polarised proton target. The data are compared with predictions from current theoretical analyses. 相似文献
73.
J.L. Hardwick 《Journal of Molecular Spectroscopy》1985,109(1):85-98
The failure of selection rules on Ka, v, and vibronic symmetry in the visible band systems of NO2 are interpreted as resulting from the coupling of the excited electronic state with vibrational levels of the ground electronic state which are above the threshold for ergodic motion and therefore retain no quantization of those observables. This failure is shown to lead directly to the anomalous continuum fluorescence of NO2, and is intimately related to the anomalous lengthening of the radiative lifetime of the excited state (the Douglas effect). It is predicted that most molecules which exhibit anomalous lifetime lengthening will also exhibit anomalous selection rules and, consequently, anomalous continuum emission. 相似文献
74.
75.
H. Palka R. Bailey H. Becker E. Belau T. Böhringer M. Bosman V. Chabaud C. Damerell C. Doum H. Dijkstra S. Gill A. Gillman R. Gilmore T. Gooch Z. Hajduk C. Hardwick B. D. Hyams J. Kemmer R. Klanner U. Kotz S. Kwan G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer M. Pepé J. Richardson G. de Rijk K. Rybicki H. J. Seebrunner U. Stierlin H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,35(2):151-157
Using the ACCMOR spectrometer equipped with a vertex telescope of high resolution silicon microstrip detectors 74 decays \(D^ + \to \bar K^{*0} (892)e^ + v_e \) (andcc.) withx F <0.4 have been observed in 200 GeV π? Be interactions. The cross-section forD ± production, itsx F -dependence in the central region and theD ± lifetime have been measured. 相似文献
76.
H. Dijkstra R. Bailey E. Belau T. Böhringer M. Bosman V. Chabaud C. Damerell C. Daum G. de Rijk S. Gill A. Gillman R. Gilmore Z. Hajduk C. Hardwick W. Hoogland B. D. Hyams R. Klanner S. Kwan U. Kötz G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé J. Richardson K. Rybicki H. J. Seebrunner U. Stierlin R. J. Tapper H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers A. Wylie T. Zeludziewicz 《Zeitschrift fur Physik C Particles and Fields》1986,32(3):349-351
Experimental results on inclusive ? production are compared with the Lund model for lowp T hadronic interactions. The data is based on a sample of 600,000 ? mesons in the kinematic rangep T <1.0 (GeV/c)2 and 0.0<x F<0.4, produced in π±,K ±,p and \(\bar p\) Be interactions at 100 GeV/c and 120 GeV/c incident momentum. The Lund model reproduces the shapes of the longitudinal differential cross sections reasonably well, but the relative cross sections for incident, π,K andp show a discrepancy with the data. 相似文献
77.
Hardwick CC Herivel TR Hernandez SC Ruane PH Goodrich RP 《Photochemistry and photobiology》2004,80(3):609-615
A medical device using riboflavin (RB) and light is being developed for the reduction of pathogens in platelet concentrates (MIRASOL pathogen reduction technology [PRT]). A high-performance liquid chromatography (HPLC) method for the quantification of RB and its main photoproduct, lumichrome (LC) in blood components has been developed and validated. In addition, the same method has been used to identify and quantify the presence of additional photoproducts-catabolites of RB. Levels of these agents before and after treatment as well as endogenous levels present in normal donor blood are reported using this analytical technique. The method allows for quantitative and qualitative analysis of RB and LC in blood components using HPLC-fluorescence detection, a Zorbax SB-CN (stable bond cyano) column and a methanol-water mobile phase. Quantitation and qualitative analysis of additional photoproducts of RB was also performed, but the method has not been validated for these other components. The method described has passed an 8 day validation and has been found to be adequate for its intended use. The range of the method for RB is 0.016-1.500 microM and for LC is 0.060-1.500 microM. The method detection limit for RB is 0.0006 microM and for LC is 0.012 microM. The acceptance criteria for repeatability were met; the relative standard deviation for RB was 0.64% and for LC was 0.76%. The acceptance criteria for bias were met with a 97% average recovery for RB and a 102% recovery for LC. Samples were centrifuged and diluted 1:50 with 0.9% saline before analysis. No protein precipitation or extraction was required. A mass balance of approximately 93.4-94.4% was achieved after exposure of products to UV light in the intended pathogen reduction treatment method. The method permitted the identification of photoproducts in blood that were both naturally occurring and produced after photolysis of blood samples treated with the PRT process. The identity of these photoproducts has been established using HPLC Tandem Mass Spectrometry (MS/MS) and UV spectroscopic methods and has been correlated with known metabolites and catabolites of RB. HPLC with fluorescence detection using a reverse phase cyano-column allows for accurate separation, identification and quantification of both RB and LC in blood products without the need for solvent extraction or protein precipitation. Additional photoproducts could also be identified and quantified using this method. The presence of these agents in normal, untreated blood suggests that their presence in blood is ubiquitous. 相似文献
78.
The title compounds were prepared from 1-lithio-undecafluorobicylco(2,2,1)-heptane, and from 1H,4-lithio-decafluorobicyclo(2,2,1)heptane and 1H-decafluorobicyclo(2,2,1)hept-4-yl magnesium iodide with mercuric chloride. With sulphur and caesium fluoride in dimethyl formamide, both mercurials gave the corresponding thioxides and these on hydrolysis gave the known bridgehead thiols. With sulphur alone, the undecafluoro mercurial gave mainly the disulphide and a range of polysulphides, under conditions which left the 4H-decafluoro mercurial unchanged. Conventional d.c. polarography of the mercurials indicated an inconsistency in the use of this method for determining the acidities of highly fluorinated hydrocarbons. 相似文献
79.
Background
Delays between actions and their outcomes severely hinder reinforcement learning systems, but little is known of the neural mechanism by which animals overcome this problem and bridge such delays. The nucleus accumbens core (AcbC), part of the ventral striatum, is required for normal preference for a large, delayed reward over a small, immediate reward (self-controlled choice) in rats, but the reason for this is unclear. We investigated the role of the AcbC in learning a free-operant instrumental response using delayed reinforcement, performance of a previously-learned response for delayed reinforcement, and assessment of the relative magnitudes of two different rewards. 相似文献80.
Hydrophobic chromatography was investigated as a purification procedure for human liver hexosaminidases. Both phenyl-Sepharose and valine-Sepharose have a high binding capacity for hexosaminidases. A degree of resolution between the A and B isozymes is achieved with phenyl-Sepharose.Both hydrophobic supports myst be used close to their capacity in order to recover the applied enzyme.Two purification procedures for human liver hexosaminidase B were employed, which resulted in recoveries of approximately 48 and 24% with final specific activities of 33,400 and 4840 nmole/min·mg, respectively. 相似文献