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91.
In this study, antimicrobial polycaprolactone composite films containing 12.5% silica and 0.15% silver nanorods were prepared using the roll‐milling method. The destruction of E. coli and S. aureus on the surface of the composite films was evaluated after 6 hr of incubation at 37°C. For the E. Coli, no bacterial contamination was detected after 6 hr and the film surface was completely disinfected with 100% reduction of the microbial contamination. For the S. aureus, 94% reduction of the bacterial contamination was observed after 6 hr. The results were compared with the composite films containing triclosan, a broad‐spectrum antimicrobial agent. The antimicrobial activity tests with 0.25% triclosan incorporated polycaprolactone‐silica composite films showed only 70% reduction of E. coli and 95% reduction of S. aureus after 6 hr. The results demonstrated that the use of silver nanoparticles in the biopolymer industry has huge potential for the self‐cleaning applications. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
92.
93.
Identifying Different Types of Catalysts for CO2 Reduction by Ethane through Dry Reforming and Oxidative Dehydrogenation 下载免费PDF全文
Dr. Marc D. Porosoff Myat Noe Zin Myint Dr. Shyam Kattel Zhenhua Xie Elaine Gomez Dr. Ping Liu Prof. Dr. Jingguang G. Chen 《Angewandte Chemie (International ed. in English)》2015,54(51):15501-15505
The recent shale gas boom combined with the requirement to reduce atmospheric CO2 have created an opportunity for using both raw materials (shale gas and CO2) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H2). The second route is oxidative dehydrogenation which produces ethylene using CO2 as a soft oxidant. The results of this study indicate that the Pt/CeO2 catalyst shows promise for the production of synthesis gas, while Mo2C‐based materials preserve the C? C bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X‐ray absorption near‐edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions. 相似文献
94.
New ruthenium(II) complexes containing η6-arene-η1-pyrazole ligands were synthesized and characterized by elemental analysis and spectroscopic methods. In addition, the molecular structure of dichloro-3,5-dimethyl-1-(pentamethylbenzyl)-pyrazole–ruthenium(II), [Ru]L3b, was determined by X-ray diffraction studies. These complexes were applied in the transfer hydrogenation of acetophenone by isopropanol in the presence of potassium hydroxide. The activities of the catalysts were monitored by NMR. 相似文献
95.
96.
We consider two notions for the representations of convex cones G-representation and lifted-G-representation. The former represents a convex cone as a slice of another; the latter allows in addition, the usage of auxiliary
variables in the representation. We first study the basic properties of these representations. We show that some basic properties
of convex cones are invariant under one notion of representation but not the other. In particular, we prove that lifted-G-representation is closed under duality when the representing cone is self-dual. We also prove that strict complementarity
of a convex optimization problem in conic form is preserved under G-representations. Then we move to study efficiency measures for representations. We evaluate the representations of homogeneous
convex cones based on the “smoothness” of the transformations mapping the central path of the representation to the central
path of the represented optimization problem.
Research of the first author was supported in part by a grant from the Faculty of Mathematics, University of Waterloo and
by a Discovery Grant from NSERC. Research of the second author was supported in part by a Discovery Grant from NSERC and a
PREA from Ontario, Canada. 相似文献
97.
Sung Il Ahn Chang Woo OHk Jae Hyun Kim Wang‐Cheol Zin 《Journal of Polymer Science.Polymer Physics》2009,47(22):2281-2287
The continuous‐multilayer model introduced in our previous study for the Tg behavior of thin films is adapted to nanocomposite systems. Tg enhancement in both thin films and nanocomposites with attractive interfacial interactions can be explained by the same model. Various shapes of nanoparticles are proposed to rationalize the adaptation of the one‐dimensional model for the Tg behavior of thin film to three‐dimensional system such as nanocomposite. The tendency of predicted Tg enhancements in poly(methyl methacrylate) and P2VP nanocomposites with silica particles are qualitatively fit to experimental data in literatures. For the further quantitative fitting, the model is partially modified with the consideration for other factors affecting Tg deviation in nanocomposite. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2281–2287, 2009 相似文献
98.
Standard INDO parameters are used in ‘sum-over-states’ perturbation calculations of nJ(NC) in a variety of molecular environments. Good agreement with the experimental data is, in general, obtained when the integral products SN2(o)SC2(o) and 〈r?3〉N〈r?3〉C assume the values of 35.167 a.u.?3 and 4.980 a.u.?3, respectively. For ‘pyridine-type’ nitrogen atoms the major contribution to nJ(NC) usually arises from the orbital term whereas the contact term dominates the values of nJ(NC) for ‘pyrrole-type’ and amino nitrogen atoms. 相似文献
99.
Giovanni Zin 《Annali di Matematica Pura ed Applicata》1963,62(1):351-383
Sunto Si estende dapprima allo spazio euclideo a quattro dimensioni e poi allo spazio-tempo pseudoeuclideo la particolare classe
di funzioni tensoriali di un vettore che, in una memoria precedente dello stesso autore, era stata considerata limitatamente
allo spazio euclideo tridimensionale. Tali tensori godono della proprietà che al mutare del sistema di riferimento le espressioni
analitiche delle nuove componenti del tensore, scritte rispetto alle nuove componenti del vettore, conservano l'invarianza
formale. L'analisi di tali funzioni tensoriali mette in evidenza che le espressioni analitiche delle loro componenti risultano
indeterminate a meno di un piccolo numero di funzioni del solo modulo del vettore, chiamate funzioni di distanza (f. d. d.).
Dall' attuale analisi risulta che il numero delle f. d. d. atte ad individuare un tensore dello stesso ordine diminuisce con
l aumentare del numero delle dimensioni dello spazio. Così per il tenore del 20 ordine si hanno tre funzioni di distanza nell' S3 e due nell' S4. Per il tensore del 30 ordine si hanno 7 f. d. d. nell' S3 e 5 nell' S4. Il tensore ql, m, n emisimmetrico negli indici l ed n è individuato nello spazio-tempo da una sola f. d. d.
Nell' ultima parte della memoria si cerca un' interpretazione dell' elettromagnetismo di Maxwell-Lorentz mediante le dette
funzioni tensoriali nello spazio-tempo. Si compone il detto tensore emisimmetríco ql, m, n con il tetraelemento di linea oraria percorsa da una carica puntiforme in moto e si integra lungo la linea oraria. Il detto
tensore ql, m, n è funzione, appartenente alla classe in considerazione, del tetrasegmento che unisce il punto-evento in cui si trova la carica
con il punto-evento in cui si vuole calcolare il campo elettromagnetico da essa generato. Scegliendo opportunamente l' unica
f. d. d. che individua ql, m, n è possibile ottenere il tensore elettromagnetico generato dalla carica.
Si riesce così ad isolare l' aspetto geometrico dell' elettromagnetismo di Maxwell-Lorentz dall'aspetto analitico, che consiste
nella particolare f. d. d. del tensore elettromagnetico ql, m, n. 相似文献
100.