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81.
Philosophers have been concerned for some time with the epistemic caliber of the general public, qua the body that is, ultimately, tasked with political decision-making in democratic societies. Unfortunately, the empirical data paint a pretty dismal picture here, indicating that the public tends to be largely ignorant on the issues relevant to governance. To make matters worse, empirical research on how ignorance tends to breed overconfidence suggests that the public will not only lack knowledge on the relevant issues, but also wisdom, in the Socratic sense of an awareness of your ignorance. While increasing the knowledge and wisdom of the public might be thought an obvious remedy, there is, as far as sound political decision-making and action are concerned, nothing particularly valuable about knowledge or wisdom per se. In fact, it might just be that what the public needs is nothing but the most basic epistemic good: true belief.  相似文献   
82.
In the article above published in Volume 17 of Polymers for Advanced Technologies, pages 790–793 (2006) and online in Wiley InterScience , ( www.wileyinterscience.wiley.com ) DOI 10.1002/pat.786 the following changes should be recognised: On the second page of the paper, page 791, the sentence above figure 2 should have read ‘Since the headgroup areas of surfactants are a weak function of the condition under which they are used the function …’  相似文献   
83.
Immobilization of submonolayers to 4-5 multilayers of organic molecules on carbon surfaces can be performed by in situ generation of aryl radicals from aryltriazenes. The central idea consists of oxidatively forming an electrogenerated acid of N,N'-diphenylhydrazine to convert the aryltriazene to the corresponding diazonium salt in the diffusion layer of the electrode. In a second step, the diazonium salt is reduced at the same electrode to give a surface of covalently attached aryl groups. In this manner, various moieties tethered to the aryl groups can be immobilized on the surface. Here a ferrocenyl group was introduced as redox marker, the electrochemical signal of which is extraordinarily well-defined. This behavior is independent of film thickness, the latter being easily controlled by the number of repetitive cycles performed. It is also demonstrated that the new approach is suitable for patterning of surfaces using scanning electrochemical microscopy.  相似文献   
84.
Collagen, the major component of extracellular matrix (ECM) and the most abundant protein in the human body, is implicated in the development of atherosclerosis. Collagen types I and III were immobilized on fused-silica capillary to investigate their shape, size and structure by atomic force microscopy (AFM). For comparison, collagen was also immobilized on a mica surface. Our studies demonstrated that not only does the adsorption pattern on the substrate vary with the type of collagen, but also the substrate material plays an important role in the fibril formation process. Decorin, which promotes the binding of low-density lipoprotein (LDL) particles with collagen, was investigated for its effect on the fibrillogenesis. On both substrate materials, addition of decorin clearly reduced the fibril diameter of collagen surfaces. Moreover, a quartz crystal microbalance (QCM)-based biosensor approach was applied to clarify and evaluate the affinity of different collagen coatings immobilized on a silicon dioxide sensor chip toward apolipoprotein B-100, the major protein of LDL. The results confirmed the importance of collagen type and their fibrillogenesis on the binding of the positive residues of apolipoprotein B-100 on negatively charged collagen surfaces.  相似文献   
85.
Optical nanoparticle pH sensors designed for ratiometric measurements have previously been synthesized using post-functionalization approaches to introduce sensor molecules and to modify nanoparticle surface chemistry. This strategy often results in low control of the nanoparticle surface chemistry and is prone to batch-to-batch variations, which is undesirable for succeeding sensor calibrations and cellular measurements. Here we provide a new synthetic approach for preparing nanoparticle pH sensors based on self-organization principles, which in comparison to earlier strategies offers a much higher design flexibility and high control of particle size, morphology and surface chemistry.  相似文献   
86.
We report the first observation of a shoulder in the radiation spectrum from GeV electrons in a structured target consisting of two thin and closely spaced foils. The position of the shoulder depends on the target spacing and is directly connected to the finite formation length of a low-energy photon emitted by an ultrarelativistic electron. With the present setup it is possible to control the separation of the foils on a μm scale and hence measure interference effects caused by the macroscopic dimensions of the formation length. Several theoretical groups have predicted this effect using different methods. Our observations have a preference for the modified theory by Blankenbecler but disagree with the results of Baier and Katkov.  相似文献   
87.
This paper investigates the stability of traveling wave solutions to the free boundary Euler equations with a submerged point vortex. We prove that sufficiently small-amplitude waves with small enough vortex strength are conditionally orbitally stable. In the process of obtaining this result, we develop a quite general stability/instability theory for bound state solutions of a large class of infinite-dimensional Hamiltonian systems in the presence of symmetry. This is in the spirit of the seminal work of Grillakis, Shatah, and Strauss (GSS) , but with hypotheses that are relaxed in a number of ways necessary for the point vortex system, and for other hydrodynamical applications more broadly. In particular, we are able to allow the Poisson map to have merely dense range, as opposed to being surjective, and to be state-dependent. As a second application of the general theory, we consider a family of nonlinear dispersive PDEs that includes the generalized Korteweg–de Vries (KdV) and Benjamin-Ono equations. The stability or instability of solitary waves for these systems has been studied extensively, notably by Bona, Souganidis, and Strauss , who used a modification of the GSS method. We provide a new, more direct proof of these results, as a straightforward consequence of our abstract theory. At the same time, we allow fractional dispersion and obtain a new instability result for fractional KdV. © 2020 Wiley Periodicals, Inc.  相似文献   
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