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21.
Telecommunication Systems - Integration of optical and millimeter-wave systems provide a promising solution for future giga-bits per second wireless communication systems. We have proposed and...  相似文献   
22.
In the present study,an enviro-friendly synthesis of silver nanoparticles from Berberis lycium Royle leaf extract and their antibacterial efficacy against five pathogenic bacteria were investigated.This biosynthesis technique is proved to be advantageous over physical and chemical methods as no toxic chemicals are used.The structural and morphological characterization was made by UV-visible spectroscopy,scanning electron microscopy,and transmission electron microscopy.The synthesized nanoparticles were oval,rectangular,and spherical in shape,size ranges from 8 to 100 nm and exhibited an absorption peak at 458 nm.The biosynthesized silver nanoparticles have shown good antibacterial effect toward tested bacteria.It is believed that these biosynthesized silver nanoparticles can play a vital role in nano-based products in future.  相似文献   
23.

In this work, a low temperature aqueous chemical growth methodology was used for the fabrication of CuO nanostructures. The as-synthesised nanostructures were then elaborately characterised by number of analytical techniques such as scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The obtained nanostructures were observed to possess interlaced rice-shaped structural features with the length and width of individual rice determined to be in the range of 200–300 nm and 50–100 nm respectively. The unique nanostructures when utilised as electrode material exhibited excellent electro-catalytic potential towards oxidation of hydrazine in alkaline media. The excellent conductive of CuO added by the high surface area of obtained nanorice-like structures enabled development of highly sensitive (3087 µA mM−1 cm−2), selective and stable electrochemical sensor for hydrazine. In addition, the successfully application of the developed sensor in spiked tap, bottled and industrial water samples for the detection of hydrazine suggested its feasibility for practical environmental application.

  相似文献   
24.
Microsystem Technologies - The objective of this research paper is to find the way to guide the worms in an electric field gradient for a specific time period. Research has been done to guide the...  相似文献   
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It is a common practice to model multi‐storey tall buildings as frame structures where the loads for structural design are supported by beams and columns. Intrinsically, the structural strength provided by the walls and slabs are neglected. As the building height increases, the effect of lateral loads on multi‐storey structures increases considerably. The consideration of walls and slabs in addition to the frame structure modelling shall theoretically lead to improved lateral stiffness. Thus, a more economic structural design of multi‐storey buildings can be achieved. In this research, modelling and structural analysis of a 61‐storey building have been performed to investigate the effect of considering the walls, slabs and wall openings in addition to frame structure modelling. Sophisticated finite element approach has been adopted to configure the models, and various analyses have been performed. Parameters, such as maximum roof displacement and natural frequencies, are chosen to evaluate the structural performance. It has been observed that the consideration of slabs alone with the frame modelling may have negligible improvement on structural performance. However, when the slabs are combined with walls in addition to frame modelling, significant improvement in structural performance can be achieved. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
27.
Development in graphite, graphene, and graphene nanoplatelet composites with epoxy matrix is presented here. Graphite and its modified forms propose exclusive properties to composites. Graphene has developed as subject of huge scientific attention due to excellent electron transport, mechanical properties, and high surface area. When combined appropriately with epoxy, these atomically thin carbon sheets can expressively progress physical properties even at very small loading. Epoxy/graphene nanoplatelet nanocomposite with enhanced properties was also reported. We summarized and compared electrical, thermal, and mechanical properties of epoxy composites derived from these three nanofillers. Potential of carbon fillers with epoxy matrix is also discussed.  相似文献   
28.
Various types of synthetic polymeric membranes have been fabricated for separation purposes in industry/laboratory. Zeolite is ceramic-based material and well known for its antiwear resistance and high mechanical strength. Mixed matrix membranes are the latest membrane technology constituting inorganic nanoparticle phase and organic polymer phase. The review represents various types and applications of zeolite-reinforced polymeric membranes. Consequently, fabrication procedure and working principle of zeolite-reinforced mixed matrix (polyimide, polysulfone, polycarbonate) membranes have been discussed. The significant relevance of polymer/zeolite membranes is in water purification, medical, catalytic, and gas separation industries. Improvement in polymeric membrane properties has been observed through incorporation of zeolite filler.  相似文献   
29.
In this review, main focus is on the different types of fire retardants, their properties, and pertinent potential. Both inorganic (titania, silica, and zinc oxide) and organic (graphite, graphene, and graphene nanoplatelet) compounds have been discussed as flame inhibitors. Among various sorts of fire retardants, halogen-based flame inhibitors possess outstanding features. Consequently influence of fire retardant on the performance of epoxy composite has been discussed. It was noted that significant enhancement occurs by addition of organic and inorganic fillers in epoxy matrix. However, halogen additives impart better flame resistance to epoxy composite. Toward the end of this review, potential of halogen-containing fire retardant is discussed.  相似文献   
30.
A polyurethane (PU) was developed from poly(dimethylamine‐co‐epichlorohydrin‐co‐ethylenediamine) (PDMAE) and polyethylene glycol (PEG) as soft segment and 2,4‐toluene diisocyanate (TDI) incorporating as hard segment. Later PU was blended with poly(ethylene‐co‐ethyl acrylate) (PEEA). Poly(vinyl alcohol)‐functionalized carbon black (CB‐PVA) nanoparticles was used as filler. The structure, morphology, mechanical, crystallization, and shape memory behavior (heat and voltage) were investigated methodically. Due to physical interaction of the blend components, unique self‐assembled network morphology was observed. The interpenetrating network was responsible for 83% rise in tensile modulus and 46% increase in Young's modulus of PU/PEEA/CB‐PVA 1 hybrid compared with neat PU/PEEA bend. Electrical conductivity was increased to 0.2 Scm?1 with 1 wt % CB‐PVA nanofiller. The original shape of sample was almost 94% recovered using heat induced shape memory effect while 97% recovery was observed in an electric field of 40 V. Electroactive shape memory results were found better than heat stimulation effect. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43481.  相似文献   
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