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991.
The heat content of solid and liquid AuSb2 compound was measured from 298 K to T (375–963 K) on heating (drop method) with the help of a Tian-Calvet calorimeter. The heat capacity of the liquid compound as well as its enthalpy of fusion were deduced. The enthalpy of the liquid decreases strongly when temperature increases between the melting point and 831 K.

The enthalpy of formation of the Au---Sb melts was also determined by direct reaction calorimetry at 916 K with respect to concentration. The enthalpy of mixing is weakly negative in the whole range of concentration (minf = −3·47 kJ/mol at xAu = 0·775) in agreement with the results of Béja at 923 K. disagree with the much more negative earlier data of Kameda et al. and of Hino et al. by emf and vapor pressure measurements.

Finally, the liquid/Au(cr) phase boundary determined at 916 K from the break in the hf (xAu) curve agrees well with the phase diagram calculated by Okamoto and Massalski but not with their experimental results.  相似文献   

992.
Factors involved in the activity decay of an ultrafiltration reactor during the hydrolysis of hemoglobin by pepsin were studied. Biochemical and hydrodynamic parameters were assessed. The product of hydrolysis showed no inhibitory effect. Autolysis and mechanical damage of pepsin were limited by the presence of hemoglobin. Activity decay was mainly a result of the leakage of pepsin through the membrane. Electrostatic charges carried by either hemoglobin or pepsin were involved in the permeation process.  相似文献   
993.
The present article concerns neural based image processing and solutions developed for industrial problems using the ZISC-036 neuro-processor, an IBM hardware processor which implements the Restricted Coulomb Energy algorithm (RCE) and the K-Nearest Neighbor algorithm (KNN). The developed neural based techniques have been applied for image enhancement in order to restore old movies (noise reduction, focus correction, etc.), to improve digital television images, or to treat images which require adaptive processing (medical images, spatial images, special effects, etc.). We also have developed and implemented on ZISC-036 neuro-processor, a neural network based solution for visual probe mark inspection in VLSI production for the IBM Essonnes plant. The main characteristics of such systems are real-time control and high reliability in detection and classification tasks. Experimental results, validating presented concepts, have been reported showing quantitative and qualitative improvement as well as the efficiency our solutions.  相似文献   
994.
In his book The Expression of the Emotions in Man and Animals, Charles Darwin (1872/1965) defended the argument that emotion expressions are evolved and adaptive (at least at some point in the past) and serve an important communicative function. The ideas he developed in his book had an important impact on the field and spawned rich domains of inquiry. This article presents Darwin's three principles in this area and then discusses some of the research topics that developed out of his theoretical vision. In particular, the focus is on five issues--(a) the question of what emotion expressions express, (b) the notion of basic emotions, (c) the universality of emotion expressions, (d) the question of emotion prototypes, and (e) the issue of animal emotions--all of which trace their roots to Darwin's discussion of his first two principles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
Antioxidants are believed to be important in the prevention of diseases such as cancer and cardiovascular disease. Lycopene is one of the main antioxidants to be found in fresh tomatoes and processed tomato products. The lycopene content also accounts for the redness of the fruit, which is one of the main qualities for which industry and consumers now look. Other carotenes (such as β‐carotene), vitamin C, vitamin E and various phenolic compounds are also thought to be health‐promoting factors with antioxidant properties. Since the antioxidant content of tomatoes may depend on genetic factors, the choice of variety cultivated may affect the results at harvest. To be able to control the antioxidant content of tomatoes at the field level when growing a given variety, it is necessary to know the effects of both environmental factors and the agricultural techniques used. Temperatures below 12 °C strongly inhibit lycopene biosynthesis and temperatures above 32 °C stop this process altogether. The effects of the temperature on the synthesis of other antioxidants have not yet been properly assessed. The effects of light have been studied more thoroughly, apart from those on vitamin E. The effects of water availability, mineral nutrients (nitrogen, phosphorus, potassium and calcium) and plant growth regulators have been studied, but results are sometimes contradictory and the data often incomplete. During the ripening period, lycopene content of tomatoes increases sharply from the pink stage onwards, but no sufficient attempts have been made so far to assess the changes in the other antioxidants present in the fruit. This paper reviews the present state of the art. Copyright © 2003 Society of Chemical Industry  相似文献   
996.
Twelve consecutive patients admitted for bleeding from ruptured gastric varices were treated with transjugular intrahepatic portosystemic shunts and followed for a mean of 6 +/- 3 months (range: 8-293 days). The shunt was performed successfully in all 12 patients. The shunt occluded in 3 patients (respectively 19, 101 and 103 days after insertion) of whom one remained asymptomatic and two experienced rebleeding. Four patients presented with acute encephalopathy, spontaneously in two and after rebleeding in two. Three patients died, two after rebleeding and one of septic shock secondary to pneumonia. Overall, 9 patients survived a mean of 211 +/- 92 days with no rebleeding, 8 of whom have not yet experienced any complications. These results suggest that transjugular intrahepatic portosystemic shunts could be useful in treating hemorrhages from ruptured gastric varices and in preventing their recurrence.  相似文献   
997.
This paper describes the router developed for ALPS, the analogue layout prototyping system. the ALPS router employs some classic techniques and contributes a new, fast implementation of a maze-running algorithm and a new algorithm for finding two disjoint paths in a graph (the so-called ‘two path problem’). Discussion of these points is coupled with a review of existing routing algorithms and techniques, and comparisons where possible.  相似文献   
998.
A general method for solving the differential equations describing the heat transfer process within a rock bed is presented. A numerical model accounting for secondary phenomena such as thermal losses and conduction effect is developed. The results of the study are presented in the form of curves and empirical equations. Two applications of this theoretical model are then investigated. One is the elaboration of a new calculation method for the volumetric convective heat transfer coefficient using the compared results of theoretical modeling and experimental tests. The second application is a design method for solar applications of rock-bed storage with determination of optimal values for parameters such as air velocity, particle diameter and geometrical aspects of the storage unit.  相似文献   
999.
The determination of fatigue life of components containing defects usually takes into account crack propagation only. In a real situation, a number of cycles are often required to reach fatigue crack initiation and predictive evaluation of fatigue crack initiation phases of real defects in austenitic stainless steel welded joints are presented. Fatigue crack growth rates in wrought and cast austenitic stainless steels and associated welds are also presented. Effects of various mechanical parameters (R ratio and variable amplitude loading) of a PWR environment and of metallurgical factors (δ ferrite content and ageing in cast austenitic stainless steels) are discussed.  相似文献   
1000.
(00l)‐Oriented La2Ti2O7 (LTO) thin films with monoclinic perovskite‐layer structure [a = 7.806(2) Å, b = 5.552(3) Å, c = 13.015(5) Å, β = 98.62(2)°] have been grown by a sol–gel route on conducting (110)‐oriented doped Nb:SrTiO3 (STO) substrates. The narrow rocking curves (0.24° width for 004LTO peak) demonstrate the sharp mosaïcity of the films. Using high‐resolution X‐ray diffraction (HR‐XRD), epitaxial relationships between the LTO, and the STO substrate are given. In addition, HR‐XRD evidences the existence of (212)‐oriented crystallites 1.5° disoriented with respect to the plane of the substrate. We confirm, by DFT calculations, that the polarization vector lies in the b‐axis of the LTO cell and consequently, the existence of these (212)‐oriented crystallites enables to explain the origin of the various contrasts observed both on the in‐plane and out‐of‐plane images when collected by piezoresponse force microscopy. Finally, both successful poling experiments performed via the tip of atomic force microscope and the existence of local piezoloops within the domains, unambiguously confirm the ferroelectric state of the films at the nanoscale level. Once again, this study demonstrates that a clear understanding of nanoscale piezoelectric/ferroelectric phenomena in oriented thin films passes through a carefully structural analysis as performed by HR‐XRD.  相似文献   
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