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111.
S.N. Bhatia C.J. O''Connor R.L. Carlin H.A. Algra L.J. de Jongh 《Chemical physics letters》1977,50(3):353-357
The magnetic properties of Cu(NH3)4(NO3)2 have been measured at low temperatures. Broad maxima in both the susceptibility and specific heat are observed and are consistent with linear chain behavior of a Heisenberg antiferromagnet, with J/k = 3.9 ± 0.1 K. Long-range order sets in at Tc = 0.15 ± 0.01 K, and the ratio kTc/|J| = 0.038 is the lowest observed as yet for a one-dimensional, S = 1/2 antiferromagnet. 相似文献
112.
We report here our investigations using Monte Carlo and molecular dynamics (MD) simulations, as well as quasi-elastic neutron
scattering experiments, to study the adsorption and diffusion of H2 and D2 in zeolite Rho. In the simulations, quantum effects are incorporated via the Feynman-Hibbs variational approach. At low temperatures,
we observe a reversal of kinetic molecular sieving in which D2 diffuses faster than H2. Based on fits of bulk data, we suggest new set of potential parameters for hydrogen, with the Feynman-Hibbs variational
approach used for quantum corrections. The transport properties obtained from MD simulations are in excellent agreement with
the experimental results, with both showing significant quantum effects on the transport at low temperature. The MD simulation
results on two different structures of zeolite Rho clearly demonstrate that the quantum effect is very sensitive to pore size.
High transport flux selectivity is noted at low temperatures, suggesting feasibility of kinetic isotope separation. 相似文献
113.
Bhanja R Joseph R Tuli SK Beri SB Bhatia VS Kaur G Kaur M Mittra IS Bhalla KB Bharti A Lokanathan S Gupta SK Gupta VK Kaul GL Kumar V Mangotra LK Prakash Y Rao NK Sankhydhar S Satti S Claesson G Garpman S Herrström NY Jakobsson B Lund I Norén B Oskarsson A Otterlund I Persson S Sherif MM Söderström K 《Physical review letters》1985,54(8):771-774
114.
115.
L. Rosenthaler J. Grant F. A. Meggy F. Feigl V. Demant N. A. Orlow H. Fritz S. L. Bhatia A. A. Benedetti-Pichler W. F. Spikes K. P. Yorks Mary L. Willard J. B. Ekeley C. Banta E. Widmer I. M. Korenman N. S. Poluektoff G. Beck E. Schantl L. Kuhlberg S. Messonshnik M. Vrtiš R. Uzel W. Manchot P. Woringer J. V. Dubsky E. Krametz W. R. Dunstan T. S. Dymond M. T. Koslowsky A. J. Penner J. V. Tamchyna 《Analytical and bioanalytical chemistry》1937,111(9-10):349-362
116.
117.
Tarlok Singh Lobana Mani Kaushal Robin Bhatia Ritu Bala Ray J. Butcher Jerry P. Jasinksi 《Acta Crystallographica. Section C, Structural Chemistry》2022,78(1):30-35
In this investigation, the crystal structures of the thio-ligands 3-formylpyridine 4-phenylthiosemicarbazone (C13H12N4S, 1 ) and 4-benzoylpyridine 4-ethylthiosemicarbazone (C15H16N4S, 2 ), and of two new coordination compounds, chlorido(3-formylpyridine 4-phenylthiosemicarbazone-κS)bis(triphenylphosphane-κP)copper(I) acetonitrile monosolvate, [CuCl(C13H12N4S)(C18H15P)2]·CH3CN, 3 , and bis(3-formylpyridine 4-ethylthiosemicarbazonato-κ2N1,S)nickel(II), [Ni(C9H11N4S)2], 4 , are reported. In complex 3 , the thio-ligand coordinates in a neutral form to the Cu atom through its S-donor atom, and in complex 4 , the anionic thio-ligand chelates to the Ni atom through N- and S-donor atoms. The geometry of complex 3 is distorted tetrahedral [bond angles 99.70 (5)–123.23 (5)°], with the P—Cu—P bond angle being the largest, while that of complex 4 is square planar, with trans-S—Ni—S and N—Ni—N bond angles of 180°. 相似文献
118.
Agrawal SK Sanabria-DeLong N Bhatia SK Tew GN Bhatia SR 《Langmuir : the ACS journal of surfaces and colloids》2010,26(22):17330-17338
We report the energetics of association in polymeric gels with two types of junction points: crystalline hydrophobic junctions and polymer-nanoparticle junctions. Time-temperature superposition (TTS) of small-amplitude oscillatory rheological measurements was used to probe crystalline poly(L-lactide) (PLLA)-based gels with and without added laponite nanoparticles. For associative polymer gels, the activation energy derived from the TTS shift factors is generally accepted as the associative strength or energy needed to break a junction point. Our systems were found to obey TTS over a wide temperature range of 15-70 °C. For systems with no added nanoparticles, two distinct behaviors were seen, with a transition occurring at a temperature close to the glass transition temperature of PLLA, T(g). Above T(g), the activation energy was similar to the PLLA crystallization enthalpy, suggesting that the activation energy is related to the energy needed to pull a PLLA chain out of the crystalline domain. Below T(g), the activation energy is expected to be the energy required to increase mobility of the polymer chains and soften the glassy regions of the PLLA core. Similar behavior was seen in the nanocomposite gels with added laponite; however, the added clay appears to reduce the average value of the activation enthalpy. This confirms our SAXS results and suggests that laponite particles are participating in the network structure. 相似文献
119.
We have measured the magnetic susceptibility (χ) and heat capacity (C
p) of β-Cu2−x
Zn
x
V2O7 (x = 0, 0.05, 0.1, 0.15, 0.2, 0.3, 2) in the temperature range 2–300 K. A one-dimensional alternating exchange Heisenberg antiferromagnetism
(HAF) is observed in all compositions with chains of infinite length. The intra-chain exchange remains uniform and decreases
marginally with dilution of the magnetic state. A cooperative ordering is seen in the magnetic chains for all Zn concentrations
(x ≤ 0.3). The temperature of occurrence of this transition decreases with increasing Zn concentration. Though the conventional
spin-wave theory has been used here to describe the properties of the ordered phase, the presence of some contributions like
the lattice heat capacity in C
p and the Curie-Weiss term in susceptibility introduces some uncertainties in the estimation of the proportions contributed
by the spin system. Therefore, the nature of the ordered phase could not be ascertained unambiguously. 相似文献
120.
N-Arylation of pridazinone derivatives 1 with an aryl or heteroaryl bromide or iodide 2 has been achieved in 70-94% isolated yield using catalytic amounts of the stable and structurally well defined copper catalyst 4b under standard Ullmann-Goldberg reaction conditions. The structure of copper catalyst 4b was characterized by ESI-MS, DSC and the single crystal X-ray. 相似文献