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31.
It is very important to detect and correct faults for ensuring the validity and reliability of reversible circuits. Test vectors play an important role to detect as well as correct the faults in the circuits. The optimum number of test vector implies the more capabilities for detecting several types of faults in the circuits. In this paper, we have proposed an algorithm for generating optimum test vectors. We have shown that the proposed algorithm generates optimum test vectors with the least complexity of time as compared to existing methods, i.e., we have proved that the proposed algorithm requires O(log 2 N) time, whereas the best known existing method requires O(N. log 2 N) time, where N is the number of inputs. We have also proposed another algorithm for detecting faults using the generated test vectors. This proposed method can detect more faults than existing ones. We have proved that the proposed fault detection algorithm requires least time complexity as compared to the best known existing methods, i.e., the proposed algorithm requires O(d. 1/N) time, whereas the best known existing methods require O(d. N) time, where N is the number of inputs and d is the number of gates in a reversible circuit. Finally, we have proposed another algorithm for correcting the detected faults. We have also proved that the proposed methods require the least time complexity as compared to the best known existing methods. In addition, the experimental results using benchmark circuits show the efficiency of the proposed methods.  相似文献   
32.
Summary Cross-linked poly(vinylene-arsine)s (4) were synthesized by a free-radical terpolymerization of phenylacetylene (2), hexaphenylcyclohexaarsine (l), and p- or m-diethynylbenzene (p- or m-3) at different compositions in the presence of a catalytic amount of AIBN. The number-average molecular weights of the resulting polymers were a few thousands estimated by gel permeation chromatography (GPC) analysis. By gas chromatography (GC) analysis p-3 was found to be more reactive during the polymerization than m-3 and the resulting cross-linked polymer (p-4) showed lower solubility than that of m-4. The cross-linked poly(vinylene-arsine)s showed higher glass transition temperature in the measurement of differential scanning calorimetry (DSC) and more red-shifted emission in chloroform solution than that of the linear poly(vinylene-arsine). These properties could be tuned by varying the monomer feed ratio.  相似文献   
33.
The aim of this study was to investigate the shelf-life of commercial sliced dry fermented sausage during storage at different temperatures. Different laminate composition was used for vacuum and nitrogen (100% N2) packaging. The microbiological, physico-chemical and sensory parameters were analysed during 120 days storage at 4, 22 and 37 °C. Packaging materials were analysed for their barrier characteristic (oxygen permeability).  相似文献   
34.
The present study investigated the effects of azuki bean (Vigna angularis) extract (VAE) on the progress of atopic dermatitis (AD)-like skin lesions in NC/Nga mice induced by 1-chloro-2,4-dinitrobenzene. The efficacy of VAE in NC/Nga mice was determined by measuring gross and histological skin lesions, serum IgE levels, eosinophil ratio in peripheral leucocytes, and mRNA expression levels of interleukin (IL)-4, tumour necrosis factor (TNF)-α and interferon (IFN)-γ in splenocytes. Continuous ingestion of VAE inhibited the development of the AD-like skin lesions in a dose-dependent manner. In the VAE-treated mice, the numbers of mast cells in the skin, eosinophil ratio in peripheral leucocytes, relative mRNA expression of inflammatory cytokines in the spleen, and serum IgE levels were significantly reduced. Results suggest that VAE can inhibit the development of AD-like skin lesions in NC/Nga mice by regulating immune mediators and cells, and may be an effective alternative therapy for AD.  相似文献   
35.
Novel core‐shell latices with a partially crosslinked hydrophilic polymer core and a hard hydrophobic shell of polystyrene were prepared to improve optical properties of coated paper such as gloss and brightness. These core‐shell latices were prepared by sequential addition of a monomer mixture of styrene, n‐butylacrylate and methacrylic acid. Different crosslinkers were used to form the polymer core and in the second stage styrene to form the hard shell component. In addition, attempts were made to further improve optical properties by introducing a new polymerizable optical brightener, i.e., 1‐[(4‐vinylphenoxy)methyl]‐4‐(2‐phenylethylenyl)benzene during polymerization either into the core or into the shell. The prepared core‐shell latex particles were used as specialty plastic pigments for paper coating together with kaolin as the primary pigment. The runability of paper coating formulation by either using a laboratory scale Helicoater or pilot scale JET‐coating machine was very good. The produced coated papers were printed on both sides employing a heat set web offset (HSWO) printer to study the quality of image reproduction in terms of print gloss, print mottle, print through, etc. The core‐shell latices improved the overall print quality. Furthermore, the results demonstrated that by optimizing polymer composition one can significantly enhance the optical properties and surface smoothness of coated paper. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
36.
37.
Novel organic–inorganic hybrid pigments were prepared by in situ imidization of poly(styrene-co-maleic anhydride) (SMA) aqueous dispersion with ammonia in the presence of inorganic pigments, i.e. kaolin (K) or a mixture of kaolin (K)/alumina trihydrate (ATH). The objective was to allow the organic nano-particles of poly(styrene-co-maleimide) (SMI) to precipitate during their formation onto the surface of the inorganic pigment(s) and to investigate their potential in paper coatings. The produced hybrid pigments were characterized by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT-FTIR), scanning electron microscopy (SEM), wide-angel X-ray diffraction (WXRD) spectroscopy and their particle sizes were determined by dynamic light scattering technique. By FTIR measurements the formation of maleimide was confirmed and the existence of strong hydrogen bonding between organic and inorganic components could also be detected. Whereas, the SEM images revealed that the surface of silicate layers had successfully been to a large extent covered by the organic nano-particles to give raise to novel hybrid particles. In addition, the particle size measurements support the observation that the organic nanoparticles for the most part had been chemically or physically attached to the larger inorganic particles. Thus, this in situ imidization process in the presence of clay particles provides a neat method of dispersing the formed nanoparticles onto the inorganic surface through hydrogen bonding. The produced hybrids were applied as auxiliary pigments in paper coating where they improved gloss without roughening the paper surface.  相似文献   
38.
39.
Low temperature fluidity is important for lubricating oil. Viscoelastic solid transition temperature at atmospheric pressure TVE0 represents the low temperature fluidity of lubricating oil, which is estimated from the occurrence of photo elastic effect by lowering the temperature using liquid nitrogen. Sound velocity in lubricating oil is measured using Sing around technique. Then the adiabatic Bulk modulus K is calculated from the measured sound velocity. A relation is found between the adiabatic bulk modulus and the viscoelastic solid transition temperature of lubricating oil. The relation depends on the molecular structure of lubricating oil. The oils of a group belong to almost same molecular structure, follows the same relation. For same molecular structure TVE0 decreases as decreasing the adiabatic bulk modulus of lubricating oil. It is also found that, the viscoelastic solid transition temperature of blend oils can be predicted from the base oils’ TVE0 and K.  相似文献   
40.
Rock materials used in road construction contain heavy metal elements bound in minerals that are more or less soluble. There are no requirements for investigations of leaching behaviour before use of rock materials in Sweden, which is the case regarding other materials as, e.g., slags. This implies that there is a lack of data to be used when other materials are evaluated. Seven rock materials and two gravels representing non‐weathered material for use in base or sub‐base course from three counties in Sweden have been investigated regarding mineral composition in order to explain the leaching behaviour. Microscopic studies of the mineral composition, acid‐base‐accounting and pH‐measurements have been used to explain the leaching results achieved with the availability test. The identified transparent minerals were the expected silicate minerals for the sampled rock‐forming materials. Overall, the content of identified opaque minerals was low. How an element is bound in the mineral is decisive for the dissolution of the heavy metal elements. Sulphide bound elements have a notably high fraction that is soluble, especially under oxidising conditions. Chromium and vanadium present as substituted ions in the crystal lattice of oxides are not dissolved. The dissolution of the buffering rock forming silicates is much slower than the dissolution of the acid‐producing sulphides. The results have been compared to similar leaching tests of metallurgical slag used in road construction. The dissolution of the major phase, the solubility of the heavy metal mineral and secondary reactions are factors influencing the dissolved amounts of heavy metal elements. Compared to the crystalline rock materials, the amorphous fuming slag from a copper smelter has very low solubility, while blast furnace slag is easily dissolved due to hydrolysis. The soluble amounts of sulphide bound elements in rock material is higher compared to blast furnace slag. The kinetics of the acid‐producing and acid‐consuming reactions of the rock materials needs to be further investigated. The blast furnace slag and the fuming slag can be used in road construction without any risk of harmful environmental impact due to heavy metal leaching.  相似文献   
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