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In the present study, physicochemical, pasting and antioxidant properties of six wheat (Triticum aestivum L.) cultivar grains after 24, 48 and 72 h of germination duration were evaluated and compared with their un-germinated counterparts. Chemical compositions of un-germinated fraction of whole flour were also determined. The results showed that swelling power decreased whereas solubility increased as the time of germination increased. From 24 to 72 h water and oil absorption capacities increased significantly with germination. The DPPH radical scavenging activity and reducing power exhibited significant (p?≤?0.05) increase with germination for all the cultivars. Total phenolic content ranged from 463.6 to 644.6 µg ferulic acid equivalents (FAE)/g for un-germinated to 1255.5–2380.9 µg FAE/g for germinated whole grain flour. Total flavonoids content increased from 86.5 to 266.7 µg catechin equivalents (CE)/g for un-germinated to 289.7–385.4 µg CE/g as the duration of germination increased from 0 to 72 h. The characteristics curves showing pasting profile of different cultivars became nearly linear for 48 and 72 h germinated grain flour. Several, significant correlations were observed among studied properties from principal component analysis.  相似文献   
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The cryogenic treatment of tool steels has transformed over centuries from black art to science, but the metallurgical principles responsible for increase in wear resistance, tensile strength, toughness, and stability are still disputed. Metallurgists comprehend how tool steels respond to cryogenic treatment, but they also understand that for many years, the cryogenic treatment of tool steels had the reputation of being a quick fix for poor heat treatment practice. During the cryogenic treatment of tool steels, the process modifies the carbon present in the tool steels. However, cryogenic treatment has not been widely adopted by the cutting tools industry due to lack of understanding of the fundamental metallurgical mechanisms and due to the wide variation in reported research findings. In the present paper, an attempt has been made to review the literature on metallurgical changes that occurred during the cryogenic treatment of tool steels to benefit the cutting tools industry. The prominent reasons found to be responsible for improving the mechanical properties of tool steels are transformation of retained austenite to martensite and precipitation of fine carbides.  相似文献   
45.
Test data volume amount is increased multi-fold due to the need of quality assurance of various parts of the circuit design at deep submicron level. Huge memory is required to store this enormous test data which not only increases the cost of the ATE but also the test application time. This paper presents an optimal selective count compatible run length (OSCCPRL) encoding scheme for achieving maximum compression for reduction of the test cost. OSCCPRL is a hybrid technique that amalgamates the benefits of other two techniques: 10 Coded run length (10 C) and Selective CCPRL (SCCPRL) proposed here. These techniques work on improvement of the 9 C and CCPRL techniques. In OSCCPRL, entire data is segmented in blocks and further compressed using inter block and intra block level merging techniques. SCCPRL technique is used for encoding the compatible blocks while the 10C is used to do encoding at sub block (half block length) level. In case, if no compatibility is found at block/sub block level then the unique pattern is held as such in the encoded data along with the necessary categorization bits. The decompression architecture is described and it is shown how by just the addition of few states of FSM, better test data compression can be achieved as compared to previous schemes. The simulation results performed for various ISCAS benchmarks circuits prove that the proposed OSCCPRL technique provides an average compression efficiency of around 80 %.  相似文献   
46.
Cold spray is an emerging technology that produces high density metallic coatings with low oxide contents and high thermal conductivity, which makes them ideal for high temperature corrosion resistance. In the current investigation, Ni-20Cr alloy powder was deposited on SA 516 boiler steel (0.19C-1.07Mn-0.020S-0.25P-0.010Si-balance Fe) by cold spray process. Oxidation kinetics was established for the uncoated and cold spray Ni-20Cr coated boiler steel in an aggressive environment of Na2SO4-60%V2O5 at 900 °C for 50 cycles by the weight change technique. X-ray diffraction, FE-SEM/EDAX, and x-ray mapping techniques were used to analyze the oxidation products. Uncoated steel suffered corrosion in the form of intense spalling and peeling of its oxide scale, which may be due to the formation of unprotective Fe2O3 oxides. The Ni-20Cr coating was successful in reducing the weight gain of the steel by 87.2% which may be due to the formation of oxides of nickel and chromium.  相似文献   
47.
In the current investigation, hydroxyapatite (HA) powder was mixed with titania (TiO2) in 50:50?wt?pct for depositing composite coatings on a Ti-alloy substrate using a thermal-spray coating technique. The coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS) analyses. The corrosion behavior of the coatings was studied by electrochemical corrosion testing in simulated human body fluid. After the corrosion testing, the samples were analyzed by XRD and SEM/EDS analyses. HA and TiO2 (rutile) were the main phases observed in the developed coatings. Bulk HA coating was amorphous; however, the addition of TiO2 effectively improved the crystallinity of HA in HA-TiO2 coating. The SEM analysis confirmed the formation of a well-formed HA-TiO2 composite coating. HA coating exhibited higher bond strength (67.8?MPa) compared with HA-TiO2 composite coating (37.6?MPa). The electrochemical study showed a significant improvement in the corrosion resistance of the Ti alloy after the deposition of the coatings.  相似文献   
48.
Rapid prototyping (RP) or layered manufacturing (LM) technologies have been extensively used to manufacture prototypes composed mainly of plastics, polymers, paper, and wax due to the short product development time and low costs of these technologies. However, such technologies, with the exception of selective laser melting and sintering, are not used to fabricate metallic products because of the resulting poor life, short cycle, poor surface finish, and low structural integrity of the fabricated parts. The properties endowed by these parts do not match those of functional parts. Therefore, extensive research has been conducted to develop new additive manufacturing (AM) technologies by extending existing RP technologies. Several AM technologies have been developed for the fabrication of metallic objects. These technologies utilize materials, such as Ni-, Al-, and Ti-based alloys and stainless steel powders, to fabricate high-quality functional components. The present work reviews the type of materials used in laser-based AM processes for the manufacture of metallic products. The advantages and disadvantages of processes and different materials are summarized, and future research directions are discussed in the final section. This review can help experts select the ideal type of process or technology for the manufacturing of elements composed of a given alloy or material (Ni, Ti, Al, Pb, and stainless steel).  相似文献   
49.
VLSI design has caused a revolution in microminiaturization. The design process requires construction of stick diagrams for the digital circuit to be designed. These diagrams are prepared using different colored layers. The color graphics and the color monitors make the overall system quite expensive. The object of this article is to show how an inexpensive personal computer like the Apple MacIntosh can be used for preparing VLSI stick diagrams. The Apple MacIntosh's capabilities include translation, mirroring, detail work and hatching; which are indispensible in the construction of stick diagrams. The stick diagrams for a few examples such as serial adder, half adder, adder/subtractor and generalized pipeline array cell have been worked out. It is hoped that this paper will aid in making VLSI design easier on less expensive and easily obtainable personal computers.  相似文献   
50.
We have designed efficient quantum circuits for the three-qubit Toffoli (controlled–controlled-NOT) and the Fredkin (controlled-SWAP) gate, optimized via genetic programming methods. The gates thus obtained were experimentally implemented on a three-qubit NMR quantum information processor, with a high fidelity. Toffoli and Fredkin gates in conjunction with the single-qubit Hadamard gates form a universal gate set for quantum computing and are an essential component of several quantum algorithms. Genetic algorithms are stochastic search algorithms based on the logic of natural selection and biological genetics and have been widely used for quantum information processing applications. We devised a new selection mechanism within the genetic algorithm framework to select individuals from a population. We call this mechanism the “Luck-Choose” mechanism and were able to achieve faster convergence to a solution using this mechanism, as compared to existing selection mechanisms. The optimization was performed under the constraint that the experimentally implemented pulses are of short duration and can be implemented with high fidelity. We demonstrate the advantage of our pulse sequences by comparing our results with existing experimental schemes and other numerical optimization methods.  相似文献   
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