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21.
22.
The part of the Internet of Things composed of devices that directly interact with users has grown considerably in the past years. With new smartphones, tablets and other Internet-enabled devices that appear on the market, this trend is still increasing. However, existing application development processes and tools, designed for single device applications, do not allow developers to fully and efficiently address this opportunity. Applications are developed for a particular type of devices or a particular programming platform. This limits the number of potential users and makes it difficult to seamlessly use an application on multiple devices owned by users. To take full advantage of the Internet of Things, applications should be able to run on any device—they should be ubiquitous. In this paper, we present a concept of Device-Independent Architecture, which provides separation of applications from devices and facilitates development of device-independent applications. Additionally, the separation introduced by the Device-Independent Architecture enables implementation of multi-device scenarios where a single application employs multiple devices at the same time. The experiment described in the paper proves that such device-independent applications indeed may be used on any suitable device—they have a chance to become ubiquitous.  相似文献   
23.
Depending on the calcium:phosphorus molar ratio of the initial precipitates determined by precipitation conditions (calcium:phosphorus molar ratio of reactants and pH of reaction environment), after sintering at 1250°C, monophase, biphase, or triphase ceramics consisting of hydroxyapatite, β-tricalcium phosphate, α-tricalcium phosphate, and calcium oxide were obtained. The phase composition and properties—i.e., density, shrinkage, hardness, bending strength, and roughness—of the fractured surfaces of the isostatically re-pressed sinters were determined.  相似文献   
24.
The thermal cracking and catalytic cracking processes of low-density polyethylene were studied in a closed autoclave. The compositions of gaseous and liquid products were analysed by means of GC/FID and GS/MS chromatographic methods. The fractional composition of liquid products was found by distillation. Increased temperature of PE depolymerisation process increases the production of gaseous products and low-boiling liquid compounds; more aromatic hydrocarbons are formed instead of alkenes. When a lower temperature and longer time are adopted for the process to reach the assumed conversion, more straight chained hydrocarbons are produced. The acidic aluminosilicate catalyst yields more low-boiling liquid fractions, more isoalkanes and more aromatics. The neutral alumina is favourable for the production of alkenes and vacuum gas oil fraction in comparison to a non-catalytic process. The Ni–Mo/Al2O3 catalyst is efficient in hydrogenation of depolymerisation products. The reaction products contain only saturated compounds then and no aromatics are formed.  相似文献   
25.
The formation and stability of BaAl2O4 and BaCeO3 in Pt-Ba/Al2O3 and Pt-Ba/CeO2 based NOx storage-reduction (NSR) catalysts has been investigated using kinetic measurements, X-ray diffraction, thermal analysis and X-ray absorption spectroscopy. In as-prepared state, the Ba-component in the NSR catalysts was made up of amorphous BaO and BaCO3. The formation of BaAl2O4 started above 850 °C, whereas the formation of BaCeO3 was already observed at 800 °C and was faster than that of BaAl2O4. The stability of BaAl2O4 and BaCeO3 in various liquid and gaseous atmospheres was different. BaAl2O4 was rapidly hydrated at room temperature in the presence of water and transformed to Ba(NO3)2 and γ-alumina in the presence of HNO3, whereas BaCeO3 was decomposed to much lower extent under these conditions. Interestingly, BaCeO3 was transformed to Ba(NO3)2/CeO2 in the presence of NO2/H2O at 300–500 °C. Also, the presence of CO2 led to decomposition of barium cerate, which has important consequences for the catalyst ageing under NOx-storage conditions and can be exploited for regeneration of thermally aged NSR-catalysts.  相似文献   
26.
1H-NMR and Eu(fod)3 lanthanide shift reagent were used to determine tetrad distribution of comonomer units of the PDT/FT copolyterephthalate obtained from terephthaloyl chloride (intermonomer) and 3,3′-dimethylbisphenol A and phenolphtalein (comonomers). Computer simulations of the terephthalic proton signal split into the lines of compositional tetrads were performed to obtain quantitative data. To characterize the microstructure of the copolymer samples synthesized at different temperatures, the degree of randomness and the degree of alternation were calculated. It was shown that the latter can differentiate the chains which seemed to be identical concerning the diad distribution only.  相似文献   
27.
The effects of homopolymer and copolymer compositions and structures in styrene/n-butyl acrylate (Sty/BA) latices on sodium dioctyl sulfosuccinate (SDOSS) surfactant mobility and its preferential concentration at the film–air (F–A) and film–substrate (F–S) interfaces were examined using attenuated total reflectance Fourier transform infrared (ATR FTIR) spectroscopy. It appears that the SDOSS concentration at the F–S interface is highest when the Sty/BA feed ratio is 50/50, and the excess of Sty results in migration of SDOSS surfactant to the F–A interface. This behavior is attributed to the increased glass transition temperature and diminished compatibility between surfactant molecules and copolymer latex. This study also shows that the primary factors that influence exudation to either F–A or F–S interfaces are surface tension of the substrate, glass transition temperature, water flux during coalescence, and compatibility between latex components. © 1995 John Wiley & Sons, Inc.  相似文献   
28.
The adsorption of acetonitrile and reduction of adsorbed molecules at platinized platinum electrode were studied by potentiodynamic and radiometric techniques. During acetonitrile adsorption the reversibly and irreversibly adsorbed species are formed. One electron reduction process occurs in the potential range 0.45-0.15 V. Below 0.15 V the deeper reduction of adsorbed acetonitrile takes place — the final products are ammonia and ethane. The differences of smooth and platinized platinum electrodes properties are briefly discussed.  相似文献   
29.
Marek Gryta 《Desalination》2002,142(1):79-88
Growth of microorganism in the membrane distillation (MD) system has been evaluated, and their presence on the membrane surface was studied using scanning electron microscopy (SEM) coupled with energy dispersion spectrometry (EDS). The membrane samples were collected from MD modules used for the following applications: concentration of salts and acids, production of demineralized water from tap water, separation of ethanol from fermentation broth in a membrane bioreactor and treatment of saline wastewater containing Pseudomonas and Streptococcus faecalis bacteria and Penicillium and Aspergillus fungi. The MD experiments were performed with polypropylene capillary membranes. SEM examinations of the membranes used for the treatment of saline wastewater indicated a significant amount of S. faecalis bacteria and Aspergillus fungi. The polypropylene membranes used did not reject S. faecalis bacteria, which were detected on the membrane surface on the distillate side. The presence of fungi in the membrane pores was observed only on the feed side. The contamination of the membrane surface by yeast cells was not observed in the case of the membrane bioreactor operated over one year. The running conditions of the MD process (such as elevated temperature, significant salt concentrations and low pH values) inhibited the growth of microorganism in the MD system.  相似文献   
30.
The primary purpose of this paper is to discuss the role of empathy in the design of advanced systems in manufacturing and service industries in order to ensure suitable working conditions for employees from the social and technological point of view. The origins and components of empathy are briefly reviewed. The neural underpinnings of three components of empathy, including cognitive, emotional, and behavioral aspects, are considered in the context of human–human and human–machine interactions, as well as design of working environments. Finally, the potential advantages of applying empathy‐related knowledge to the design and development of human‐centered technology are discussed.  相似文献   
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