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61.
In this paper, we will incorporate the generalized uncertainty principle into field theories with Lifshitz scaling. We will first construct both bosonic and fermionic theories with Lifshitz scaling based on generalized uncertainty principle. After that we will incorporate the generalized uncertainty principle into a non-abelian gauge theory with Lifshitz scaling. We will observe that even though the action for this theory is non-local, it is invariant under local gauge transformations. We will also perform the stochastic quantization of this Lifshitz fermionic theory based generalized uncertainty principle. 相似文献
62.
Kaushik Biswas Atul D. Sontakke M. Majumder K. Annapurna 《Journal of Thermal Analysis and Calorimetry》2010,101(1):143-151
This paper reports results on the crystallization kinetics of 35.5CaO–7.25La2O3–57.25B2O3 glass under nonisothermal conditions based on the studies carried out from the differential thermal analysis upon using various well-established models. The crystalline phases formed during the optimized ceramization process have been confirmed from the X-ray diffraction. The activation energies of the first (formation of CaLaB7O13) and second (formation of LaBO3) crystallization events have been estimated using the conventional methods of Kissinger, Augis–Bennett, Ozawa, and Matusita, and the results are found to be in good agreement with each other. The Avrami exponents that are determined by these models for the crystallization of CaLaB7O13 and LaBO3 are found to be in the range of (1.81–2.35) and (4.03–4.65), respectively. This indicates that the formation of CaLaB7O13 is dominated by a surface crystallization, whereas LaBO3 is formed by three-dimensional bulk crystallization with an increased rate of nucleation. This observation is further validated by microstructural investigation, which shows the formation of CaLaB7O13 phase as a surface layer and a bulk crystallization of LaBO3 in optimally ceramized samples. 相似文献
63.
The geometric and electronic structures of Si(n), Si(n)-, and PSi(n-1) clusters (2 < or = n < or = 13) have been investigated using the ab initio molecular orbital theory formalism. The hybrid exchange-correlation energy functional (B3LYP) and a standard split-valence basis set with polarization functions (6-31+G(d)) were employed to optimize geometrical configurations. The total energies of the lowest energy isomers thus obtained were recalculated at the MP2/aug-cc-pVTZ level of theory. Unlike positively charged clusters, which showed similar structural behavior as that of neutral clusters [Nigam et al., J. Chem. Phys. 121, 7756 (2004)], significant geometrical changes were observed between Si(n) and Si(n)- clusters for n = 6, 8, 11, and 13. However, the geometries of P substituted silicon clusters show similar growth as that of negatively charged Si(n) clusters with small local distortions. The relative stability as a function of cluster size has been verified based on their binding energies, second difference in energy (Delta2 E), and fragmentation behavior. In general, the average binding energy of Si(n)- clusters is found to be higher than that of Si(n) clusters. For isoelectronic PSi(n-1) clusters, it is found that although for small clusters (n < 4) substitution of P atom improves the binding energy of Si(n) clusters, for larger clusters (n > or = 4) the effect is opposite. The fragmentation behavior of these clusters reveals that while small clusters prefer to evaporate monomer, the larger ones dissociate into two stable clusters of smaller size. The adiabatic electron affinities of Si(n) clusters and vertical detachment energies of Si(n)- clusters were calculated and compared with available experimental results. Finally, a good agreement between experimental and our theoretical results suggests good prediction of the lowest energy isomeric structures for all clusters calculated in the present study. 相似文献
64.
We present a cellular automaton (CA) model of particles in a single-file motion with free particle exchange at the boundaries of a one-dimensional channel connected to two infinite reservoirs in order to study the self-transmission of particles with excluded mutual passage. The parallel, local and homogeneous rule sets of the CA algorithm consider two different interactions of varying strength between particles, without any specific particle-channel interaction. CA model results suggest that one hallmark of single-file motion is the conduction bursts at a particular time scale, which have thus far only been discovered for hydrogen bond networked water translocation. The cumulative transport probabilities of particles through single-file channels of different length follow a single profile, which can be obtained through proper scaling of time. The universal features of our results suggest new experiments in single-file channel with fluids other than water. 相似文献
65.
Gokhroo G Majumder G Abe K Abe K Adachi I Aihara H Anipko D Aushev T Aziz T Bakich AM Balagura V Banerjee S Belous K Bitenc U Bizjak I Blyth S Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Eidelman S Fratina S Gershon T Go A Golob B Gorisek A Ha H Haba J Hayasaka K Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Ishikawa A Itoh R Iwasaki M Iwasaki Y Kang JH Kawai H 《Physical review letters》2006,97(16):162002
We report the first observation of a near-threshold enhancement in the D(0)D[over](0)pi(0) system from B-->D(0)D[over](0)pi(0)Kappa decays using a 414 fb(-1) data sample collected at the Upsilon(4S) resonance. The enhancement peaks at a mass M=3875.2+/-0.7(+0.3)/(-1.6) +/-0.8 MeV/c2 and the branching fraction for events in the peak is B(B-->D(0)D[over](0)pi(0)Kappa)=(1.22+/-0.31(+0.23)/(-0.30))x10(-4). The data were collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider. 相似文献
66.
The possibility of Cherenkov-like gluon bremsstrahlung in dense matter is studied. We point out that the occurrence of Cherenkov radiation in dense matter is sensitive to the presence of partonic bound states. This is illustrated by a calculation of the dispersion relation of a massless particle in a simple model in which it couples to two different massive resonance states. We further argue that detailed spectroscopy of jet correlations can directly probe the index of refraction of this matter, which in turn will provide information about the mass scale of these partonic bound states. 相似文献
67.
68.
Nonlinear waves of the reaction–diffusion (RD) type occur in many biophysical systems, including the heart, where they initiate cardiac contraction. Such waves can form vortices called scroll waves, which result in the onset of life-threatening cardiac arrhythmias. The dynamics of scroll waves is affected by the presence of inhomogeneities, which, in a very general way, can be of (i) ionic type; i.e., they affect the reaction part, or (ii) conduction type, i.e., they affect the diffusion part of an RD-equation. We demonstrate, for the first time, by using a state-of-the-art, anatomically realistic model of the pig heart, how differences in the geometrical and biophysical nature of such inhomogeneities can influence scroll-wave dynamics in different ways. Our study reveals that conduction-type inhomogeneities become increasingly important at small length scales, i.e., in the case of multiple, randomly distributed, obstacles in space at the cellular scale (0.2–0.4 mm). Such configurations can lead to scroll-wave break up. In contrast, ionic inhomogeneities affect scroll-wave dynamics significantly at large length scales, when these inhomogeneities are localized in space at the tissue level (5–10 mm). In such configurations, these inhomogeneities can attract scroll waves, by pinning them to the heterogeneity, or lead to scroll-wave breakup. 相似文献
69.
Summary Hydroxylapatite (HA), a form of calcium phosphate, finds extensive usages in the fractionation and purification of proteins,
enzymes and nucleic acids. However, commercial HA preparations for liquid chromatography (LC) differ from many other LC packing
materials in that the former is not polymer supported. We have now developed a substitute packing material which uses Fractosil
200 as the polymer support. Other polymer supports can also be similarly used. Being Fractosil 200 supported, this Hydroxylapatite
Substitute (HAS) matrix can be employed for open column LC as well as for HPLC purposes. Although the exact chemical nature
of HAS is different from the conventional HA, HAS mimicks the functions of the latter support. Due to the high’ binding capacity
of HA many DNA binding proteins have been partially purified on this support. In the present work HAS has been successfully
used in the partial purification of Topoisomerase I and II from wheat germ.
Dedicated to Professor Hartmut Seliger on his 50th birthday. 相似文献
70.
The migration sequences of silver group ions Ag+, Hg2+2, Pb+2and Ti+ have been studied in a number of complex-forming electrolytes. Based on the migration sequences, the ions in a mixture can be separated into distinct zones using a decinormal solution of sodium chloride, potassium chloride or potassium cyanide as the electrolyte. The sequence is Hg — Ag— Pb—Ti, while in KCN at pH 7.0 the sequence becomes Ag—Hg—Pb—Ti. 相似文献