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41.
Munshi G Mustafa Sudhir Raniwala T Awes B Rai RS Bhalerao JG Contreras RV Gavai SK Ghosh P Jaikumar GC Mishra AP Mishra H Mishra B Mohanty J Nayak J-Y Ollitrault SC Phatak L Ramello R Ray PK Sahu AM Srivastava DK Srivastava VK Tiwari 《Pramana》2006,67(5):961-981
This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and
work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported. 相似文献
42.
E.J. Reijerse A.M. Tyryshkin S.A. Dikanov 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,131(2):295-309
One-dimensional C- and X-band as well as two-dimensional X-band ESEEM experiments were performed on the complex oxobis(2-methylquinolin-8-olato) vanadium(IV) in frozen solution. A14N ESEEM simulation strategy based on initial first- and second-order perturbation analysis of peak positions in orientationally selected ESEEM spectra is presented. The constraint parameters extracted enable one to reduce the number of free fitting parameters for each nitrogen from 10 to 4. These are the α, β resp. the φ, θ Euler angles of the NQI and the HFI tensor defined in the coordinate system of the axialgtensor. The local symmetry of the complex allows one to reduce the number of free parameters to two angles only. Subsequently, a grid search in the remaining Euler space produced the starting parameters for the final fit of the14N hyperfine and quadrupole tensors. The anisotropic nitrogen hyperfine interaction tensor was found to be strongly nonaxial (0.06, 0.51, −0.57) MHz with the components significantly smaller than the isotropic hyperfine constant −6.18 MHz. In contrast, the quadrupole tensor withK= 0.58 MHz is close to axial (η = 0.13). These tensors share the principal axis normal to the ligand plane (as imposed by the local symmetry). The axes in the ligand plane are, however, rotated 50° with respect to each other. The orientation of the quadrupole tensor axes correlate within 10° with the orientation of the ligand plane following from the X-ray structure. 相似文献
43.
Nickolay I. Tyryshkin Alexander I. Konovalov Viktor V. Gavrilov Nina A. Polezhaeva 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):553-556
Abstract Synthesis of functionally substituted organophosphorus compounds on the basis of reactions of the tri-n-butylphosphine/carbon disulfide, tri-n-butylphosphine/phenylisothiocyanate, tris(dimethylamino)phosphine/phenylisothiocyanate adducts with a wide range of different dipolarophiles are reported. The development of application of S-Li tri-n-butylphosphonio-dithioformiate derivatives to the synthesis of new types of organophosphorus compounds are reported. 相似文献
44.
45.
V. P. Kochanov A. N. Kuryak M. M. Makogon I. S. Tyryshkin 《Optics and Spectroscopy》2006,101(2):183-190
The initial phase of development of stimulated Raman scattering (SRS) in the backward direction in compressed methane (the excess of the SRS intensity over the signal of spontaneous scattering in the experiment is ~100) has been studied theoretically and experimentally. The theory, developed on the basis of simple assumptions about the mechanism of SRS formation from spontaneous scattering, shows good agreement with experiment. The implicit consideration of backward SRS is shown to be significant for the conditions of depletion of the pump energy due to its continuous loss in the medium and conversion into SRS. 相似文献
46.
Brown RM Tyryshkin AM Porfyrakis K Gauger EM Lovett BW Ardavan A Lyon SA Briggs GA Morton JJ 《Physical review letters》2011,106(11):110504
Electron spin qubits in molecular systems offer high reproducibility and the ability to self-assemble into larger architectures. However, interactions between neighboring qubits are "always on," and although the electron spin coherence times can be several hundred microseconds, these are still much shorter than typical times for nuclear spins. Here we implement an electron-nuclear hybrid scheme which uses coherent transfer between electron and nuclear spin degrees of freedom in order to both effectively turn on or off interqubit coupling mediated by dipolar interactions and benefit from the long nuclear spin decoherence times (T(2n)). We transfer qubit states between the electron and (15)N nuclear spin in (15)N@C(60) with a two-way process fidelity of 88%, using a series of tuned microwave and radio frequency pulses and measure a nuclear spin coherence lifetime of over 100 ms. 相似文献
47.
RE Tribble A Azhari HL Clark CA Gagliardi Y-W Lui AM Mukhamedzhanov A Sattaroy X Tang L Trache V Burjan J Cejpek V Kroha S Piskor J Vincour F Carstoiu 《Pramana》1999,53(3):585-594
S-factors for direct capture reactions can be found at astrophysical energies from asymptotic normalization coefficients which
provide the normalization of the tail of the overlap function. For example the overlap for 8B → 7Be+p defines the S-factor for 7Be (p, γ)8B. Peripheral transfer reactions offer a technique to determine these asymptotic normalization coefficients. As a test of
the technique, the 16O(3He, d)17F reaction has been used to determine asymptotic normalization coefficients for transitions to the ground and first excited
states of 17F. The S-factors for 16O(p, γ)17F calculated from these 17F → 16O+p asymptotic normalization coefficients are found to be in very good agreement with recent measurements. Following the same
technique, the 10B(7Be, 8B)9Be and 14N(7Be, 8B)13C reactions have been used to measure the asymptotic normalization coefficient for 7Be(p, γ)8B. This result provides an indirect determination of S
17(0). 相似文献
48.
AM Cardoso SM Alexandre CM Barros AJ Correia NM Nibbering 《Rapid communications in mass spectrometry : RCM》1999,13(19):1885-1888
The collision-induced dissociation (CID) of deprotonated arylalkylamines of general formula R(1)C(6)H(4)CHR(2)CH(2)NR(3)(2) (where R(1) = H, OH, F or NO(2); R(2) = H or OH; R(3) = H or CH(3)) generated by negative chemical ionization with H(2)O and D(2)O as ionizing reagents, is discussed. The negative chemical ionization mass spectra show that, in the absence of a hydroxy group in the aromatic ring, deprotonation takes place at the benzylic position whereas the proton is lost from the OH group when present. The nitro compound forms only M(-.) ions. The CID spectra of the deprotonated molecules show that fragmentations are strongly dependent on the structural features of the molecules, namely the presence or absence of substituents in the aromatic ring or aliphatic chain. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
49.
AM Johnston CM Scrimgeour MO Henry LL Handley 《Rapid communications in mass spectrometry : RCM》1999,13(14):1531-1534
The conversion of nitrate (NO(3)(-)) to 1-phenylazo-2-naphthol (Sudan-1) has been examined as a method for natural abundance measurement of delta(15)N of NO(3)(-). The reaction results in dilution of NO(3)(-)-N with only one reagent-derived N and the product is readily concentrated from dilute samples by reverse phase chromatography. There is systematic isotopic fractionation during the reaction, but this can be allowed for by analysing known NO(3)(-) standards along with each sample set. Sudan-1 prepared from surface water samples containing approximately 50 &mgr;g NO(3)(-)-N can be analysed by automated continuous flow isotope ratio mass spectrometry with a precision of 0.2 per thousand (one standard deviation) and the accuracy is not affected by interference from other nitrogenous species in the sample or reagents. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
50.
Rubens R Santos Jr Alexandrina Sartori Deison S Lima Patrícia RM Souza Arlete AM Coelho-Castelo Vania LD Bonato Célio L Silva 《Journal of immune based therapies and vaccines》2009,7(1):4-12