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101.
Ram Avtar Jat Ripandeep Singh S.C. Parida A. Das Renu Agarwal K.L. Ramakumar 《International Journal of Hydrogen Energy》2014
In the present study, we have for the first time reported the occupancy of deuterium in a new interstitial site of ZrCoD3 which explain the hydrogen induced disproportionation behavior of ZrCo alloy. We have also reported the effect of Ni substitution on interstitial site occupancy of deuterium in ZrCo1−xNixD3, which in turn explains the improved durability of these Ni substituted deuterides against disproportionation. The crystal structure of the ZrCo1−xNix (x = 0.0, 0.1, 0.2, 0.3) deuterides was investigated by X-ray powder diffraction and neutron diffraction methods. The XRD data reveals a single phase formation for all deuterides with varying Ni content (x). The neutron diffraction study shows that deuterium occupies a new site 8e in addition to 4c2 and 8f1. Additionally, the Zr–D distance in 8e site is shorter than that in ZrD2. Therefore, increase in 8e site occupancy will in turn decreases the durability against disproportionation and vice-versa. Furthermore, the neutron diffraction reveals that occupancy of new 8e site decreases and its Zr–D distance increases with increase in Ni content, which explicate the higher durability against disproportionation for Ni rich compound. 相似文献
102.
103.
Pingbo Tang Gaoyun Chen Zhenglai Shen Ram Ganapathy 《Computer-Aided Civil and Infrastructure Engineering》2016,31(1):65-80
Changes of designs and construction plans often cause propagative design modifications, tedious construction coordination, cascading effects of errors, reworks, and delays in project management. Among various building elements, those having piece‐wise linear geometries (i.e., connected straight line segments), such as connected straight sections of ducts in mechanical, electrical, and plumbing systems, frequently undergo spatial changes in response to the changes of their surroundings. On the other hand, the piece‐wise linear geometries pose challenges to analyzing and controlling changes in construction and facility management. State‐of‐the‐art 3D change detection algorithms often face ambiguities about which points belong to which objects when piece‐wise linear object are spacked in small spaces. This article examines a spatial‐context‐based framework that uses spatial relationships between piece‐wise linear building elements (ducts in this article) to enable fast and reliable association of 3D data with ducts in as‐designed models for supporting reliable change analysis. Three case studies showed that this framework outperformed a conventional change detection method, and could handle large dislocations of piece‐wise linear elements and occlusions. 相似文献
104.
105.
Jesús García‐Parra Rebeca Contador Jonathan Delgado‐Adámez Francisco González‐Cebrino Rosario Ramírez 《International Journal of Food Science & Technology》2014,49(4):1203-1214
A nectarine purée was manufactured with different pretreatments (thermal blanching or ascorbic acid – AA – addition), and then, the purée was processed by high‐pressure treatment to evaluate the effect of the initial manufacture conditions in the stability of the processed purées. A thermal treatment was also carried out to compare the effect with the high‐pressure processing (HPP). All applied processes were effective to ensure the microbiological safety of the purées. However, the pretreatment (thermal blanching or AA addition) applied during the manufacture affected the final quality of the processed purées. Initially, the AA addition had a protective effect on colour degradation during the manufacture of the purées; however, when these purées were treated by HPP showed less colour stability during storage, lower bioactive compounds content, and antioxidant activity. In contrast, purées with an initial thermal blanching maintained better the quality after HPP and during storage. 相似文献
106.
Ram Swaroop Verma Rajendra Chandra Padalia Amit Chauhan 《Journal of the science of food and agriculture》2012,92(3):626-631
BACKGROUND: Two Ocimum basilicum cultivars, ‘Vikarsudha’ and ‘CIM‐Saumya’, grown in the Kumaon region of western Himalaya were evaluated for their essential oil yield and composition at different stages of plant growth during two distinct cropping seasons (spring–summer and rain–autumn). RESULTS: The highest yield of essential oil was obtained at full bloom stage in both cultivars in both cropping seasons. The essential oils obtained from different stages in two cropping seasons were analysed by capillary gas chromatography with flame ionisation detection, and gas chromatography–mass spectrometry. The major component of cultivar ‘Vikarsudha’ was methyl chavicol (84.3–94.3%), while for cultivar ‘CIM‐Saumya’ the main components were methyl chavicol (62.5–77.6%) and linalool (14.4–34.1%). CONCLUSION: This study clearly indicated that cultivar, cropping season, plant ontogeny and plant part had significant effects on the yield and quality of the essential oil of O. basilicum. Further, the amount of methyl chavicol in the cultivars grown in this region was higher than in cultivars from other parts of India. Copyright © 2011 Society of Chemical Industry 相似文献
107.
The low crustal abundance of materials such as tellurium (Te) (0.001?ppm by weight), antimony (Sb) (0.2?ppm), and germanium (Ge) (1.4?ppm) contributes to their price volatility as applications (competing with thermoelectrics) continue to grow, for example, cadmium telluride photovoltaics, antimony-lead alloy for batteries, and Ge for fiber optics and infrared optical technologies. Previous consideration of material scarcity has focused on Te-based thermoelectrics. Here, we broaden the analysis to include recent high-figure-of-merit (ZT) materials such as skutterudites, Zintl phase compounds, and clathrates that employ Sb, ytterbium (2.8?ppm), and Ge. The maximum demonstrated ZT for each particular alloy exhibits an empirical dependence on the crustal abundance, A, such that ZT?=?A ?b , where b is in the range from 0.05 to 0.10. This analysis shows that no material with crustal abundance of 30?ppm (~4?× 1018 metric tons) has ZT greater than 0.8. 相似文献
108.
An optimization algorithm inspired by the States of Matter that improves the balance between exploration and exploitation 总被引:1,自引:1,他引:0
The ability of an Evolutionary Algorithm (EA) to find a global optimal solution depends on its capacity to find a good rate between exploitation of found-so-far elements and exploration of the search space. Inspired by natural phenomena, researchers have developed many successful evolutionary algorithms which, at original versions, define operators that mimic the way nature solves complex problems, with no actual consideration of the exploration-exploitation balance. In this paper, a novel nature-inspired algorithm called the States of Matter Search (SMS) is introduced. The SMS algorithm is based on the simulation of the states of matter phenomenon. In SMS, individuals emulate molecules which interact to each other by using evolutionary operations which are based on the physical principles of the thermal-energy motion mechanism. The algorithm is devised by considering each state of matter at one different exploration–exploitation ratio. The evolutionary process is divided into three phases which emulate the three states of matter: gas, liquid and solid. In each state, molecules (individuals) exhibit different movement capacities. Beginning from the gas state (pure exploration), the algorithm modifies the intensities of exploration and exploitation until the solid state (pure exploitation) is reached. As a result, the approach can substantially improve the balance between exploration–exploitation, yet preserving the good search capabilities of an evolutionary approach. To illustrate the proficiency and robustness of the proposed algorithm, it is compared to other well-known evolutionary methods including novel variants that incorporate diversity preservation schemes. The comparison examines several standard benchmark functions which are commonly considered within the EA field. Experimental results show that the proposed method achieves a good performance in comparison to its counterparts as a consequence of its better exploration–exploitation balance. 相似文献
109.
Arijit Lodh Ujjal Tewary Ram Pratap Singh Tawqeer Nasir Tak Aditya Prakash Alankar Alankar P. J. Guruprasad Indradev Samajdar 《Metallurgical and Materials Transactions A》2018,49(12):5946-5952
Orientation-dependent developments in misorientation and residual stress, in rolled aluminum, were quantified experimentally and simulated numerically. The latter involved analysis using a crystal plasticity finite element model, accounting for anisotropies in slip system hardening but neglecting near-neighbor interactions, and discrete dislocation dynamics of the single crystals. Both were successful in capturing the experimental patterns of orientation dependence. Numerical simulations, without slip transfer across the neighboring grains, thus established the defining role of dislocation interactions in establishing orientation-sensitive microstructural evolution. 相似文献
110.
Bhowmik Showmik Sarkar Ram Nasipuri Mita Doermann David 《International Journal on Document Analysis and Recognition》2018,21(1-2):1-20
International Journal on Document Analysis and Recognition (IJDAR) - Separation of text and non-text is an essential processing step for any document analysis system. Therefore, it is important to... 相似文献