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181.
Existing visualization techniques used by mutual fund managers focus on the active portfolio management strategies. However, an important aspect of mutual funds is to visualize and understand the fund composition observed at specific points in time. Such a visualization will leverage the fund manager with the power to investigate and to capture forecasting differences and future performance. Our research here is to design a new visualization system that has an Entity-Relationship (E-R) model at the heart of the system and reveals not only the aggregate behavior of the mutual funds, but also the behavior of the mutual fund managers who manage these funds. We find some preliminary evidence that mutual funds in the world market represent a strong geographical pattern, and some potential niche markets are now extracted that stands out in the global scenario such as the returns from funds that belong to a specific country. For the analysis of security distribution, it helps to distinguish the most popular securities from other ordinary ones for an increased realization of profit. Also based on our experience with such huge world fund data to achieve a trade-off between time efficiency and graphics quality, we recommend the approach of splatting visualization, which indicates the influence of a particular security in a fund’s portfolio.  相似文献   
182.
Thermal expansion measurements have been carried out on Fe substituted superconducting compounds Y1Ba2(Cu1−x Fe x )3O y (0<x<4%) using a high resolution dilatometer employing the three terminal capacitance technique. The experimental set up is sensitive enough to detect changes in α of less than 10−8K−1. Results show that the jump Δα in the coefficient of linear thermal expansion at the superconducting transition temperature,T c, increases almost linearly with Fe concentration. The normal state thermal expansion coefficient α first decreases, attains a minimum value aroundx=1% and then increases for higher Fe concentrations. The oxygen content per unit formula is almost constant up tox=1% and then increases rapidly withx. It has also been observed that the anomalous behaviour of α around 260 K observed by Meingastet al [22] for Fe concentrationx=5% is due to inadequate annealing of the sample.  相似文献   
183.
Cumulative yields of short-lived xenon isotopes137,138,139Xe have been determined in the spontaneous fission of252Cf, using a fast radiochemical separation method followed by gamma spectrometry. Xenon-137 yield is reported for the first time. The measured cumulative yields are converted to chain yields assuming normal charge distribution systematics for comparision with the literature data.  相似文献   
184.
N,N′-diphenylbutyl-3,4,9,10-perylenebiscarboximide (PTCDI-C4Ph) were characterized by optical and electrochemical methods. A device with an ITO/PTCDI-C4Ph (≈2 μm)/Al structure was fabricated to measure mobility by time-of-flight techniques. This vacuum deposited organic layer was an amorphous state. Electrons were observed faster than holes. The electron and hole mobilities were 1.8 × 10−4 cm2/V s and 1.1 × 10−4 cm2/V s under the electric field of 500 (V/cm)1/2, respectively. This result shows that this organic compound is a good candidate for an n-type conduction.  相似文献   
185.
Summary The paper deals with the analysis of shear-flexible anisotropic plates subjected to arbitrary boundary conditions. In order to solve the pertinent boundary value problem, a Ritz-type technique has been developed which, however, ist not based on the standard principle of minimum potential energy but a modification thereof. In this variational theorem, the boundary conditions are satisfied a posteriori as natural constraints, therefore relatively simple trial functions can be used to approximate the displacement variables in the interior of the plate. Extensive studies carried out on a series of relevant examples illustrate that the proposed method represents an inexpensive, reliable and highly efficient tool for solving a wide variety of plate bending problems.
Ein sehr genaues numerisches verfahren zur näherungsweisen berechnung des tragund deformationsverhaltens schubsteifer anisotroper platten
Übersicht Die vorliegende Arbeit beschäftigt sich mit der Berechnung des Trag- und. Deformationsverhaltens beliebig gelagerter Platten unter Berücksichtigung von Materialanisotropie sowie Schubkrafteinfluß. Beim entwickelten Berechnungsverfahren handelt es sich um eine Ritz-Methode, welche allerdings nicht auf dem Prinzip des Minimums der potentiellen Energie, sondern einer Modifikation davon basiert. Das Besondere an dieser modifizierten Variationsgleichung liegt darin, daß die geometrischen Rand- und Übergangsbedingungen nicht als wesentliche, sondern als natürliche Nebenbedingungen erfüllt werden. Die Genauigkeit und praktische Relevanz der entwickelten Methode wird anhand einiger Representativbeispiele demonstriert.
  相似文献   
186.
The functions of life are accomplished by systems exhibiting nonlinear kinetics: autocatalysis, in particular, is integral to the signal amplification that allows for biological information processing. Novel synthetic autocatalytic systems provide a foundation for the design of artificial chemical networks capable of carrying out complex functions. Here we report a set of FeII4L6 cages containing BODIPY chromophores having tuneable photosensitizing properties. Electron‐rich anilines were observed to displace electron‐deficient anilines at the dynamic‐covalent imine bonds of these cages. When iodoaniline residues were incorporated, heavy‐atom effects led to enhanced 1O2 production. The incorporation of (methylthio)aniline residues into a cage allowed for the design of an autocatalytic system: oxidation of the methylthio groups into sulfoxides make them electron‐deficient and allows their displacement by iodoanilines, generating a better photocatalyst and accelerating the reaction.  相似文献   
187.
In the present study, we report the simultaneous electrochemical determination of hydroquinone (HQ), catechol (CC) and resorcinol (RC) at gold nanoparticles (Au‐NPs) decorated reduced graphene oxide (RGO) modified electrode. An enhanced and well defined peak current response with a better peak separation of HQ, CC and RC is observed at RGO/Au‐NPs composite than that of RGO and Au‐NPs modified electrodes. The fabricated modified electrode shows a wide linear response in the concentration range of 3–90 µM, 3–300 µM and 15–150 µM for HQ, CC and RC, respectively. The detection limit of HQ, CC and RC is found as 0.15 µM, 0.12 µM and 0.78 µM, respectively.  相似文献   
188.
Carbon nanomaterials have been extensively researched in the past few years owing to their interesting properties. The massive research efforts resulted in the emergence of carbon dots, which belong to the carbon nanomaterials family. Carbon dots (C‐dots) have garnered the attention of researchers mainly due to their convenient availability from organic as well as inorganic materials and also due to the novel properties they exhibit. C‐Dots have been said to overcome the era of quantum dots, referring to their levels of toxicity and biocompatibility. In this review, we focus on the discovery of C‐dots, their structure and composition, surface passivation to enhance their optical properties, the various synthetic methods used, their applications in different areas, and future perspectives. Emphasis has been given to greener approaches for the synthesis of C‐dots in order to make them cost effective as well as to improve their biocompatibility.  相似文献   
189.
Interest in the synthesis of hybrid substrates for surface‐enhanced Raman scattering (SERS) has surged recently. Hereof, in the present work, a hybrid SERS substrate CuO : Mn/Ag heterojunction has been synthesised. To accomplish this, the nanostructred Ag island film and CuO : Mn nanoparticles are synthesised by vacuum thermal evaporation method and sol–gel method respectively, and thereafter, a heterojunction between the CuO : Mn and Ag is fabricated by adsorption of CuO : Mn (10‐3 m in ethanol) on Ag island film. Further, the SERS sensitivity of CuO : Mn/Ag heterojunctions has been studied by probing methyl orange. We observed that with Mn‐doping in the lattice of CuO, the SERS signal is enhanced considerably because of ferromagnetic ordering in CuO : Mn. DFT/B3LYP/6‐311 G(d, p) method is used to calculate the energy of HOMO and LUMO level of methyl orange. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
190.
Preparation of proteins from salt‐gland‐rich tissues of mangrove plant is necessary for a systematic study of proteins involved in the plant's unique desalination mechanism. Extraction of high‐quality proteins from the leaves of mangrove tree species, however, is difficult due to the presence of high levels of endogenous phenolic compounds. In our study, preparation of proteins from only a part of the leaf tissues (i.e. salt gland‐rich epidermal layers) was required, rendering extraction even more challenging. By comparing several extraction methods, we developed a reliable procedure for obtaining proteins from salt gland‐rich tissues of the mangrove species Avicennia officinalis. Protein extraction was markedly improved using a phenol‐based extraction method. Greater resolution 1D protein gel profiles could be obtained. More promising proteome profiles could be obtained through 1D‐LC‐MS/MS. The number of proteins detected was twice as much as compared to TUTS extraction method. Focusing on proteins that were solely present in each extraction method, phenol‐based extracts contained nearly ten times more proteins than those in the extracts without using phenol. The approach could thus be applied for downstream high‐throughput proteomic analyses involving LC‐MS/MS or equivalent. The proteomics data presented herein are available via ProteomeXchange with identifier PXD001691.  相似文献   
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