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331.
332.
333.
We prove uniformL
p
estimates (Theorem 1.1) for a family of paraproducts and corresponding maximal operators. 相似文献
334.
Preparation and Properties of 1-Norbornyl Copper 1-Norbornyl copper was synthesized from copper(II) acetylacetonate and 1-norbornyl lithium. The compound shows an unexpected stability and decomposes only at ca. 80°C with precipitation of copper and formation of norbornyl radicals which were proved by spin-trap experiments. A further characterization was performed by the IR and 13C-NMR spectra. 相似文献
335.
Crystal Structures and Phase Transitions of the Tetramorphic RbGeI3 The thermal behaviour of RbGeI3 has been studied by X-ray diffraction, Raman spectroscopy, and DTA/DSC. The compound is tetramorphic. Yellow crystals of the LT-form have been obtained by crystallization from aqueous HI solutions. The orthorhombic crystal structure of LT? RbGeI3 (space group P212121; a = 10.1441(8) Å; b = 4.5460(5) Å; c = 16.8438(9) Å) shows a distorted NH4CdCl3 type structure with pyramidal GeI3 anions. Three reversible phase transformations were found by heating. In a first step at 181°C LT? RbGeI3 is transferred into the orthorhombic perovskite MT1—RbGeI3 (red, space group Pn21a; a = 8.566(3) Å; b = 11.868(6) Å; c = 8.018(4) Å; RbGeBr3 type structure) by a reconstructive phase transition. Subsequently at 221°C the phase MT2—RbGeBr3 with a rhombohedrically deformed perovskite type structure (black, space group R3m; a = 5.990(2) Å; α = 88,89(3)°; CsGeCl3 type structure) is formed. The high temperature modification HT? RbGeI3 shows the cubic perovskite type structure (space group Pm3m; a = 5.994(3) (Å) and is stable above 244°C until decomposition occurs at 334°C. 相似文献
336.
This paper provides an overview of developments in robust optimization since 2007. It seeks to give a representative picture of the research topics most explored in recent years, highlight common themes in the investigations of independent research teams and highlight the contributions of rising as well as established researchers both to the theory of robust optimization and its practice. With respect to the theory of robust optimization, this paper reviews recent results on the cases without and with recourse, i.e., the static and dynamic settings, as well as the connection with stochastic optimization and risk theory, the concept of distributionally robust optimization, and findings in robust nonlinear optimization. With respect to the practice of robust optimization, we consider a broad spectrum of applications, in particular inventory and logistics, finance, revenue management, but also queueing networks, machine learning, energy systems and the public good. Key developments in the period from 2007 to present include: (i) an extensive body of work on robust decision-making under uncertainty with uncertain distributions, i.e., “robustifying” stochastic optimization, (ii) a greater connection with decision sciences by linking uncertainty sets to risk theory, (iii) further results on nonlinear optimization and sequential decision-making and (iv) besides more work on established families of examples such as robust inventory and revenue management, the addition to the robust optimization literature of new application areas, especially energy systems and the public good. 相似文献
337.
Dr. Trine P. Petersen Sahar Mirsharghi Dr. Pia C. Rummel Dr. Stefanie Thiele Prof. Dr. Mette M. Rosenkilde Dr. Andreas Ritzén Prof. Dr. Trond Ulven 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(28):9343-9350
A three‐step continuous‐flow synthesis system and its application to the assembly of a new series of chemokine receptor ligands directly from commercial building blocks is reported. No scavenger columns or solvent switches are necessary to recover the desired test compounds, which were obtained in overall yields of 49–94 %. The system is modular and flexible, and the individual steps of the sequence can be interchanged with similar outcome, extending the scope of the chemistry. Biological evaluation confirmed activity on the chemokine CCR8 receptor and provided initial structure–activity‐relationship (SAR) information for this new ligand series, with the most potent member displaying full agonist activity with single‐digit nanomolar potency. To the best of our knowledge, this represents the first published example of efficient use of multistep flow synthesis combined with biological testing and SAR studies in medicinal chemistry. 相似文献
338.
339.
Let
J (\mathbb M2){{\mathcal J}\,(\mathbb M^2)} denote the σ-ideal associated with two-dimensional Miller forcing. We show that it is relatively consistent with ZFC that the additivity
of
J (\mathbb M2){{\mathcal J}\,(\mathbb M^2)} is bigger than the covering number of the ideal of the meager subsets of
ω
ω. We also show that Martin’s Axiom implies that the additivity of
J (\mathbb M2){{\mathcal J}\,(\mathbb M^2)} is 2
ω
.Finally we prove that there are no analytic infinite maximal antichains in any finite product of
\mathfrakP(w)/fin{\mathfrak{P}{(\omega)}/{\rm fin}} . 相似文献
340.
Pinning and depinning of driven drops on heterogeneous substrates is studied as a function of the driving and heterogeneity amplitude. Two types of heterogeneity are considered: a "hydrophobic" defect that blocks the drop in front and a "hydrophilic" one that holds it at the back. Two different types of depinning leading to sliding motion are identified, and the resulting stick-slip motion is studied numerically. 相似文献