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71.
H. P. Kimber W. E. Baulieu Jr. F. Oberhauser J. H. de Boer Th. F. Buehrr O. E. Schupp Jr. L. Duparc und E. Rogovine 《Fresenius' Journal of Analytical Chemistry》1929,77(1-2):65-68
Ohne Zusammenfassung 相似文献
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使用LUCIAE3.0模型模拟了SPS能区Pb+Pb和C+C在不同能量(Elab=20—200A GeV)和不同中心度下的重离子碰撞.并通过逐个事件的粒子温度涨落提取出了相应粒子的热容,发现对于同一碰撞系统,单位发射粒子的热容随碰撞能量的升高而下降直至饱和,随着碰撞参数b的增大而减小,而且发现单位发射粒子的热容具有随粒子质量的变大而变大的关系.同时还发现不同碰撞系统中同一种粒子具有相同的单位发射粒子热容,并给出了相应的解释. 相似文献
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76.
高能重离子碰撞中正负荷电粒子比单事例起伏研究 总被引:2,自引:0,他引:2
用强子和弦级联模型,JPCIAE及相应的Monte Carlo事例产生器,研究相对论性核–核碰撞中有限快度区间内正负荷电粒子比单事例起伏与能量、中心度、共振态衰变及快度间隔的关系.JPCIAE模型能够较好地符合CERN/SPS能区Pb+Pb碰撞的实验结果.本文还用此模型预言了RHIC能区Au+Au碰撞和ALICE能区Pb+Pb碰撞中的正负荷电粒子比单事例起伏.可以看出碰撞能量、中心度、共振态衰变及快度间隔对正负荷电粒子比单事例起伏的影响都不大. 相似文献
77.
Theoretical study was performed to investigate how the hydration of cadmium ca-tion influences the structure and properties of guanine.The aqueous environment was simulated by both explicit solvent(1-5 water molecules) model and implicit solvent model.For complexes in which Cd2+ attached to the N(7) and O(6) sites of guanine,energy analysis together with the Natural Bonding Orbital(NBO) analysis were performed to elucidate the bonding characteristics in detail.The most stable structures are penta-coordinate complexes without aqua ligand located at the guanine site.Higher number of water ligands corresponds to higher stabilization energies.Average bonding energies of G-Cd increase with the number of water molecules.Bonding energies of water ligands depend on its position in the complexes.The charge distribution of guanine changed with increasing the number of water ligands,which may also influence the base-pairing pattern of guanine.There is positive charge transfer from guanine to aqua ligand as the number of the hydration waters increases.IEFPCM optimization has results comparable to the [CdG(H2O)5]2+ structure 5a. 相似文献
78.
以水溶性聚合物为保护剂,采用化学还原法制备了银纳米粒子,分别利用透射电子显微镜、紫外可见光谱、同步光散射光谱等手段对其进行了表征,并探索了制备银纳米粒子的最佳实验条件。通过将银纳米粒子-聚合物溶液进行脱水,得到含有银纳米粒子的固态聚合物膜。将固态聚合物膜重新溶解于水,其水溶液的紫外可见光谱与脱水前的溶液进行了比较,发现两者性质并无明显差异。因此,将银纳米粒子分散固定在聚合物膜中是一种崭新而有效的银纳米粒子制备和存储方法。 相似文献
79.
Anthony W. Hager Chawne M. Kimber Warren Wm. McGovern 《Rendiconti del Circolo Matematico di Palermo》2003,52(3):453-480
An archimedean lattice-ordered groupA with distinguished weak unit has the canonical Yosida representation as an ℓ-group of extended real-valued functions on a
certain compact Hausdorff spaceY A. Such an ℓ-groupA is calledleast integer closed, orLIC (resp.,weakly least integer closed, orwLIC) if, in the representation,a ∈A implies [a] ∈A (resp., there isa′ ∈A witha′=[a] on a dense set inY A), where [r] ≡ the least integer greater than or equal tor. Earlier, we have studiedLIC groups, with an emphasis on their a-extensions. Here, we turn towLIC groups: we give an intrinsic (though awk-ward) characterization in terms of existence of certain countable suprema. This
results also in an intrinsic characterization ofLIC, previously lacking. Also,wLIC is a hull class (whichLIC is not), and the hullwlA is “somewhere near” the projectable hullpA. The best comparison comes from a (somewhat novel) factoringpA=loc(wpA), wherewpA is the “weakly projectable” hull (defined here), andlocB is the “local monoreflection”; then,wpA≤wlA≤loc(wpA), andpA≤loc(wlA), while with a strong unit, all these coincide. Numerous examples and special cases are examined. 相似文献
80.
Kimber MC Mahadevan IB Lincoln SF Ward AD Tiekink ER 《The Journal of organic chemistry》2000,65(24):8204-8209
The synthesis and fluorescent properties in the absence and presence of zinc(II) of a range of 2-substituted derivatives of N-(6-methoxy-2-methyl-8-quinolyl)-4-methylbenzenesulfonamide are described. These analogues formed complexes with zinc(II) as indicated by a bathochromic shift in their UV/vis spectra. Analogues with isobutenyl and isobutyl side chains at the 2-position formed fluorescent complexes whose fluorescence was stronger than that of the 2-methyl-containing parent. These derivatives were converted, via conversion to the phenol with boron tribromide and reaction with ethyl bromoacetate, to systems with ester-containing side chains analogous to zinquin ester, a specific cellular fluorophore for zinc(II). All of these ester derivatives formed complexes with zinc(II) resulting in a bathochomic shift in their UV/vis spectra. Compounds with isobutyl, isobutenyl, and styryl side chains exhibited increased fluorescence compared to that of zinquin ester in the presence of zinc(II). The compound with the 2-isobutyl side chain was more selective in its fluorescence for zinc(II) over cadmium(II) compared to zinquin ester. 相似文献