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91.
92.
Vasilios Kotzabasakis Konstantinos Kostakis Marinos Pitsikalis Nikos Hadjichristidis David J. Lohse Thomas Mavromoustakos Constantinos Potamitis 《Journal of polymer science. Part A, Polymer chemistry》2009,47(17):4314-4325
The Cs‐symmetry hafnium metallocene [(p‐Et3Si)C6H4]2C(2,7‐di‐tert‐BuFlu)(C5H4)Hf(CH3)2 and tetrakis(pentafluorophenyl) borate dimethylanilinium salt ([B(C6F5)4]?[Me2NHPh]+) were used as the catalytic system for the polymerization of higher α‐olefins (from hexene‐1 to hexadecene‐1) in toluene at 0 °C. The evolution of the polymerization was studied regarding the variation of the molecular weight, molecular weight distribution and yield with time. The effect of the monomer structure on the polymerization kinetics was established. The role of trioctylaluminum in accelerating the polymerization was investigated. 13C NMR spectroscopy was used to study the microstructure of the poly(α‐olefins) by the determination of the pentad monomer sequences. The thermal properties of the polymers were obtained by differential scanning calorimetry, DSC. The results were discussed in connection with the polymer microstructure. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4314–4325, 2009 相似文献
93.
Quantum dots (QDs) are inorganic semiconductor nanocrystals that have unique optoelectronic properties responsible for bringing
together multidisciplinary research to impel their potential bioanalytical applications. In recent years, the many remarkable
optical properties of QDs have been combined with the ability to make them increasingly biocompatible and specific to the
target. With this great development, QDs hold particular promise as the next generation of fluorescent probes. This review
describes the developments in functionalizing QDs making use of different bioconjugation and capping approaches. The progress
offered by QDs is evidenced by examples on QD-based biosensing, biolabeling, and delivery of therapeutic agents. In the near
future, QD technology still faces some challenges towards the envisioned broad bioanalytical purposes.
相似文献
94.
Let $G$ be a bounded Jordan domain in the complex plane. The Bergman polynomials $\{p_n\}_{n=0}^\infty $ of $G$ are the orthonormal polynomials with respect to the area measure over $G$ . They are uniquely defined by the entries of an infinite upper Hessenberg matrix $M$ . This matrix represents the Bergman shift operator of $G$ . The main purpose of the paper is to describe and analyze a close relation between $M$ and the Toeplitz matrix with symbol the normalized conformal map of the exterior of the unit circle onto the complement of $\overline{G}$ . Our results are based on the strong asymptotics of $p_n$ . As an application, we describe and analyze an algorithm for recovering the shape of $G$ from its area moments. 相似文献
95.
Callegari A Marcaccio M Paolucci D Paolucci F Tagmatarchis N Tasis D Vázquez E Prato M 《Chemical communications (Cambridge, England)》2003,(20):2576-2577
Amidoferrocenyl-functionalised single wall carbon nanotubes (Fc-SWNT) are efficient exoreceptors for the redox recognition of H2PO4-. 相似文献
96.
97.
Nikos?KatzourakisEmail author 《Calculus of Variations and Partial Differential Equations》2017,56(1):15
Consider the supremal functional applied to \(W^{1,\infty }\) maps \(u:\Omega \subseteq \mathbb {R}\longrightarrow \mathbb {R}^N\), \(N\ge 1\). Under certain assumptions on \(\mathscr {L}\), we prove for any given boundary data the existence of a map which is: Our method is based on \(L^p\) approximations and stable a priori partial regularity estimates. For item ii) we utilise the recently proposed by the author notion of \(\mathcal {D}\)-solutions in order to characterise the limit as a generalised solution. Our results are motivated from and apply to Data Assimilation in Meteorology.
相似文献
$$\begin{aligned} E_\infty (u,A) := \Vert \mathscr {L}(\cdot ,u,\mathrm {D}u)\Vert _{L^\infty (A)},\quad A\subseteq \Omega , \end{aligned}$$
(1)
- (i)a vectorial Absolute Minimiser of (1) in the sense of Aronsson,
- (ii)a generalised solution to the ODE system associated to (1) as the analogue of the Euler-Lagrange equations,
- (iii)a limit of minimisers of the respective \(L^p\) functionals as \(p\rightarrow \infty \) for any \(q\ge 1\) in the strong \(W^{1,q}\) topology and
- (iv)partially \(C^2\) on \(\Omega \) off an exceptional compact nowhere dense set.
98.
Aggelos Vazaios Nikos Hadjichristidis 《Journal of polymer science. Part A, Polymer chemistry》2005,43(5):1038-1048
Anionic polymerization and high‐vacuum techniques were used to prepare a series of well‐defined polyisoprene, polybutadiene, and polystyrene polymacromonomers. The procedure involved (1) the synthesis of styrenic macromonomers in benzene by the selective reaction of the corresponding macroanion with the chlorine of 4‐(chlorodimethylsilyl)styrene (CDMSS) and (2) the in situ anionic polymerization of the macromonomer without previous isolation. The synthesis of the macromonomers [polyisoprene macromonomer: 11 samples, weight‐average molecular weight (Mw) = 1000–18,000; polybutadiene macromonomer: 5 samples, Mw = 2000–4000; and polystyrene macromonomer: 2 samples, Mw = 1300 and 3600] was monitored by size exclusion chromatography with refractive index/ultraviolet detectors. Selectivity studies with CDMSS indicated that polybutadienyllithum had the highest selectivity, and polystryryllithium the lowest. From kinetic studies it was concluded that the polymerization half‐life times were longer but comparable to those of styrene, and they appeared to only slightly depend on the molecular weight of the macromonomer chain (at least for low degrees of polymerization of the polymacromonomer and for Mw < 7000 for the macromonomer side chain). Dependence on the polymerization degree of the polymacromonomer product was also observed. All the prepared polymacromonomers were characterized by size exclusion chromatography with refractive index, ultraviolet and two‐angle laser light scattering detectors, and NMR spectroscopy. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1038–1048, 2005 相似文献
99.
Hermis Iatrou E. Siakali-Kioulafa Nikos Hadjichristidis Jacques Roovers Jimmy Mays 《Journal of Polymer Science.Polymer Physics》1995,33(13):1925-1932
The synthesis of well-defined, nearly monodispersed, 3-miktoarm (from the greek word μlkτós meaning mixed) star copolymer of the A2B type is described. A and B is either polystyrene (PS), polybutadiene (PBd), or polyisoprene (PI). The sequential controlled addition of living anionic B and A chains to methyltrichlorosilane leads to narrow molecular weight distribution miktoarm star copolymers with homogeneous composition. Characterization was carried out by size exclusion chromatography, low-angle laser light scattering, laser differential refractometry, membrane and vapor pressure osmometry, nuclear magnetic resonance and ultraviolet spectroscopy. Analysis of [η], RH and Rv of the A2B and one A2B2 miktoarm copolymers, suggests that a small expansion of the copolymer occurs either in a good solvent for both species or in a Θ solvent for one of them, as compared with the corresponding star homopolymers. This is in contrast to results obtained on linear block copolymers, and is due to the increased occurrence of heterocontacts in the miktoarm starshaped architecture. © 1995 John Wiley & Sons, Inc. 相似文献
100.
Nikos Theodorakopoulos 《Zeitschrift für Physik A Hadrons and Nuclei》1972,254(5):399-407
The effects of adding a local 4-spin term to the nearest neighbor Ising model are studied. The relevant parameter isx, the ratio of the four- to the two-spin interaction strength. We have evaluated the first six terms of the high temperature susceptibility expansion and found them to be consistent with the value 1.75 of the critical exponent γ. The critical exponent α is shown to remain zero to first order inx, provided that the free energy is analytic inx. We also demonstrate the equivalence of the model examined to an elastic spin system with pure two-spin interactions. 相似文献