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21.
Socially Responsible Investing (SRI) is broadly defined as an investment process that integrates not only financial but also social, environmental, and ethical (SEE) considerations into investment decision making. SRI has grown rapidly around the world in the last decades. In the last years, given the causes of the 2008 financial crisis, ethical, social, environmental and governance concerns have become even more relevant investment decision criteria. However, while a diverse set of models have been developed to support investment decision-making based on financial criteria, models including also social responsibility criteria are rather scarce.  相似文献   
22.
We show that for each p∈(0,1]p(0,1] there exists a separable p  -Banach space GpGp of almost universal disposition, that is, having the following extension property: for each ε>0ε>0 and each isometric embedding g:X→Yg:XY, where Y is a finite-dimensional p-Banach space and X   is a subspace of GpGp, there is an ε  -isometry f:Y→Gpf:YGp such that x=f(g(x))x=f(g(x)) for all x∈XxX.  相似文献   
23.
It seems clear that energy production is one of the key aspects of global sustainability. Economic, social and environmental aspects must be taken into account in order to design appropriate policies and thus, multicriteria analysis becomes a very adequate tool to deal with real problems of this kind. This study was directed by the Regional Ministry of Environment of Andalucía, who wanted to know the impact on the cost and on the environmental damage of a potential mix, more focused on renewable sources. Some authorities of the Ministry acted as decision maker in the interactive process. As a result, we have built a linear multiobjective model, in order to determine the optimal electrical mix for the Spanish region of Andalucía. Namely, we determine how much electricity power should be installed and produced, by each of the eight generation systems considered (lignite, other coals, oil, natural gas, nuclear, photovoltaic, wind and mini-hydro). Apart from the economic criterion (yearly cost), we have considered the vulnerability (in terms of percentage of imported fuel) as a strategic criterion, and 12 environmental criteria, which have been derived using the Life Cycle Analysis method on the different production systems. The interactive system PROMOIN was used to solve the multiobjective problem. PROMOIN allows the decision maker to choose how to give preference information to the system, and enables changing it anytime during the solution process, which gives more flexibility to the decision maker and increases the confidence of the decision maker in the final solution.  相似文献   
24.
25.
In Bell experiments, one problem is to achieve high enough photodetection to ensure that there is no possibility of describing the results via a local hidden-variable model. Using the Clauser-Horne inequality and a two-photon nonmaximally entangled state, a photodetection efficiency higher than 0.67 is necessary. Here we discuss atom-photon Bell experiments. We show that, assuming perfect detection efficiency of the atom, it is possible to perform a loophole-free atom-photon Bell experiment whenever the photodetection efficiency exceeds 0.50.  相似文献   
26.
The use of click chemistry reactions for the functionalization of nanoparticles is particularly useful to modify the surface in a well‐defined manner and to enhance the targeting properties, thus facilitating clinical translation. Here it is demonstrated that olefin metathesis can be used for the chemoselective functionalization of iron oxide nanoparticles with three different examples. This approach enables, in one step, the synthesis and functionalization of different water‐stable magnetite‐based particles from oleic acid‐coated counterparts. The surface of the nanoparticles was completely characterized showing how the metathesis approach introduces a large number of hydrophilic molecules on their coating layer. As an example of the possible applications of these new nanocomposites, a focus was taken on atherosclerosis plaques. It is also demonstrated how the in vitro properties of one of the probes, particularly its Ca2+‐binding properties, mediate their final in vivo use; that is, the selective accumulation in atherosclerotic plaques. This opens promising new applications to detect possible microcalcifications associated with plaque vulnerability. The accumulation of the new imaging tracers is demonstrated by in vivo magnetic resonance imaging of carotids and aorta in the ApoE?/? mouse model and the results were confirmed by histology.  相似文献   
27.
A microsystem integrating electrochemical detection for the simultaneous detection of protein markers of breast cancer is reported. The microfluidic platform was realized by high precision milling of polycarbonate sheets and features two well distinguishable sections: a detection zone incorporating the electrode arrays and the fluid storage part. The detection area is divided into separate microfluidic chambers addressing selected electrodes for the measurement of samples and calibrators. The fluidic storage part of the platform consists of five reservoirs to store the reagents and sample, which are interfaced by septa. These reservoirs have the appropriate volume to run a single assay per cartridge and are manually filled. The liquids from the reservoirs are actuated by applying a positive air pressure (i.e.via a programmable syringe pump) through the septa and are driven to the detection zone via two turning valves. The application of the realised platform in the individual and simultaneous electrochemical detection of proteic cancer markers with very low detection limits are demonstrated. The microsystem has also been validated using real patient serum samples and excellent correlation with ELISA results obtained.  相似文献   
28.
Let A and B be C*-algebras. A linear map T : A → B is said to be a *-homomorphism at an element z ∈ A if ab* = z in A implies T (ab*) = T (a)T (b)* = T (z), and c*d = z in A gives T (c*d) = T (c)*T (d) = T (z). Assuming that A is unital, we prove that every linear map T : A → B which is a *-homomorphism at the unit of A is a Jordan *-homomorphism. If A is simple and infinite, then we establish that a linear map T : A → B is a *-homomorphism if and only if T is a *-homomorphism at the unit of A. For a general unital C*-algebra A and a linear map T : A → B, we prove that T is a *-homomorphism if, and only if, T is a *-homomorphism at 0 and at 1. Actually if p is a non-zero projection in A, and T is a ?-homomorphism at p and at 1 ? p, then we prove that T is a Jordan *-homomorphism. We also study bounded linear maps that are *-homomorphisms at a unitary element in A.  相似文献   
29.
This Note is devoted to the justification of an asymptotic model for quasisteady three-dimensional spherical flames proposed by G. Joulin [7]. The paper [7] derives, by means of a three-scale matched asymptotic expansion, starting from the classical thermo-diffusive model with high activation energies, an integro-differential equation for the flame radius. In the derivation, it is essential for the Lewis number – i.e., the ratio between thermal and molecular diffusion – to be strictly less than unity. In this Note, we give the main ideas of a rigorous proof of the validity of this model, under the additional restriction that the Lewis number is close to 1. To cite this article: C. Lederman et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 569–574.  相似文献   
30.
Schematization of networks   总被引:2,自引:0,他引:2  
We study the problem of computing schematized versions of network maps, like railroad or highway maps. Every path of the schematized map has two or three links with restricted orientations, and the schematized map must be topologically equivalent to the input map. Our approach can handle several types of schematizations, and certain additional constraints can be added, such as a minimum vertical distance between two paths. Our algorithm runs in O(nlogn) time, and experimental results showing the quality of the output are given.  相似文献   
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