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161.
In today’s ever changing consumer driven market economy, it is imperative for providers to respond expeditiously to the changes demanded by the customer. This phenomenon is no different in the transportation sector in which a service-oriented Group Decision Support System (GDSS) provides an important role in transportation enterprise to effectively manage and rapidly respond to the varying needs of the customer. In this paper, we explore the integration problem of service-oriented system and intelligence technology through the use of a GDSS. Initially, we analyze a service-oriented architecture and then, propose the design architecture of a service-oriented GDSS. Next, we put forward a general framework that integrates the intelligent techniques as a component into the architecture of service oriented GDSS. In addition, we illustrate how Artificial Intelligence techniques can resolve the conflicts of distributed group decisions. The paper is concluded by providing a number of applications in the railway management system that demonstrates the benefits of the utilization of a service oriented intelligent GDSS.  相似文献   
162.
As to control the increased rate of environmental pollution there is an urgent need to develop improved biodegradable materials regarding the old polymeric packaging materials. It has been done by the incorporation of carbon nanomaterials to the biodegradable starch terpolymers of acrylic acid, methyl methacrylate (MMA), acrylonitrile (AN), 2-Ethylhexyl acrylate (2-EHA), and Ethyl acrylate (EA). The starch-terpolymers were prepared through the free radical polymerization technique using AA, MMA, AN, 2-EHA, EA as monomers. Two different starch-terpolymers were further mixed with carbon nanoparticles (NPs) to form a biodegradable nanocomposite. The biodegradable starch-grafted terpolymers-carbon nanocomposites (STPC NCs) were characterized through scanning electron microscopy, Fourier-transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimeter, and UV–Visible spectrophotometry. Further, resistivity, electrical conductivity, and biodegradability tests were performed to check its properties for packing materials. The biodegradation of SGCP-composites recorded using the soil burial method was up to 78%. Starch-terpolymers were prepared via free-radical polymerization The biodegradation capability of starch-grafted terpolymers was found to be 78% The decrease in water vapor permeability and solubility proves their utilization as food packaging material  相似文献   
163.
The purpose of the study was to develop physically cross-linked novel pH-responsive gelatin – Wells–Dawson-type polyoxometalate (POM)-based self-assembled hydrogels using acrylic acid as a pH-responsive monomer. Cross-linking was achieved through electrostatic interactions between the cationic polymer and anionic Wells–Dawson POM [P2W15O56]12?. Ammonium persulfate and sodium hydrogen sulfite were used as initiators. The hydrogels were yellowish in color and exhibited low mechanical strength. Swelling, drug release, and pH sensitivity studies were conducted at pH 1.2 and 7.4. pH-dependent swelling and release of [P2W15O56]12? from the prepared hydrogels were observed, with a maximum at pH 7.4. The hydrogels were characterized by thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and Fourier transform infrared spectroscopy for evaluation of the surface morphology, hydrogel confirmation, and thermal properties. The results obtained confirmed the development of a gelatin–POM-based self-assembled hydrogel. It can be concluded that as a result of successful physical cross linking, the prepared hydrogels possess desired characteristics of a drug delivery system and can hence be used for a controlled delivery of the encapsulated polyanions. .  相似文献   
164.
ZnO is a potential candidate for photodetection utilizing the pyroelectric effect. Here, a self‐biased and translucent photodetector with the configuration of Cu4O3/ZnO/FTO/Glass is designed and fabricated. In addition, the pyroelectric effect is effectively harvested using indium tin oxide (ITO), silver nanowires (AgNWs), and a blend of AgNWs‐coated ITO as the transparent selective contact electrode. The improved rise times are observed from 1400 µs (bare condition; without the selective electrode) to 69, 60, 7 µs, and fall times from 720 µs (bare condition) to 80, 70, 10 µs for corresponding ITO, AgNWs, and AgNWs‐coated ITO contact electrodes, respectively. Similarly, the responsivity and detectivity are enhanced by about 4.39 × 107 and 5.27 × 105%, respectively. An energy band diagram is proposed to explain the underlying working mechanism based on the workfunction of the ITO (4.7 eV) and AgNWs (4.57 eV) as measured by Kelvin probe force microscopy, which confirms the formation of type‐II band alignment resulting in the efficient transport of photogenerated charge carriers. The functional use of the transparent selective contact electrode can effectively harness the pyro‐phototronic effect for next‐generation transparent and flexible optoelectronic applications.  相似文献   
165.
166.
The present study is insights into foliar epidermal anatomy for characterizing clades, and their utility in taxonomic segregation of certain species of Pteridaceae from Northern Pakistan. The leaf epidermal anatomy of 10 species of Pteridaceae representing four genera were examined using light and scanning electron microscope. A micromorphological matrix was constructed for eight qualitative and 12 quantitative characters. unweighted pair group method with arithmetic means and principal components analysis statistical analysis were performed to test the validity of foliar epidermal anatomical features as method of separating species and genera, and phylogenetic clusters among species are constructed using qualitative and quantitative traits. The qualitative characters described here are shape of epidermal cells, stomata, guard cell and subsidiary cells, anticlinal wall pattern, and trichomes types which is helpful in defining groups within Pteridaceae. In addition, the size of stomata, guard cells, subsidiary cells, stomatal pore epidermal cells, and trichomes are quantitatively analyzed. All species have hypostomatic leaves. Two types of stomata were observed in studied species, anomocytic and polocytic. Anomocytic stomata were observed in three genera namely: Adiantum, Onychium, and Chielanthes whereas Pteris can be discriminated from other genera by its polocytic stomata. On the basis of multivariate analysis present study does provides sufficient information on the taxonomic importance of foliar anatomy which validate its efficacy in species and genera discrimination. From result obtained here it is further possible to use leaf micromorphologic data in ferns phylogeny and providing basis for future taxonomic delimitation in other taxa.  相似文献   
167.
A number of herbal plants sold in herbal markets of Lahore are under adulteration threat which can pose harmful health effects to end‐user. This adulteration problem of medicinal plants can be resolved by the implication of some valuable taxonomic parameter such as leaf epidermal anatomical characteristics. Hence, this research was aimed to provide viable anatomical markers in order to resolve this adulteration issue persisted in some common marketed medicinal plants of district Lahore, that is, Cinnamomum verum Presl., Cinnamomum tamala (Buuch.‐Ham.) T.Nees&Eberm., Gymnema sylvestre (Retz.) R.Br.ex Sm., Sphaeranthus indicus Linn., Artemisia maritima Linn., Achillea millifolim L., Adhatoda vasica Nees, Butea monosperma (Lam.) Taub, and Morus nigra L. Overall multiple anatomical variations (epidermal cell shape, their length and width, type of stomata, length and width of guard cells along with presence or absence of trichomes) had been reported in the study that could be worthwhile for the correct identification of medicinal plants. Irregular shapes of epidermal cells were observed in Cinnamomum verum and Achillea millifolium while pentagonal and polygonal cells were found in their adultaerants, that is, Canella winterana and Adhatoda vasica, respectively. Types of stomata were also strikingly varied among genuine plant and its adulterant, for example, anisocytic stomata were observed in Artemisia maritima while in its adulterant (Artemisia absinthium) anomocytic stomata were found. Similarly, paracytic stomata were observed in Butea monosperma, whereas its adulterant plant (Averrhoa carambola) characteristically possessed anisocytic stomata. Hence, anatomical characteristics were proved to be a valuable taxonomic tool in resolving the adulteration issue of medicinal plants.  相似文献   
168.
We present a new technique to generate light carbon nanoparticles from regenerative sooting discharges and its use for ion implantation on aluminum and copper surfaces at an energy of 40 keV. Films formed at fluences up to 3 × 1015 C+/cm2 for aluminum and 1016 C+/cm2 for copper are studied using Raman spectroscopy, X-ray diffraction and atomic force microscopy. Raman spectroscopy reveals the existence of graphite and diamond like structures in all samples. Precipitates of Al4C3 of rhombohedral and hexagonal types were found in the nanometer ranges from the X-ray diffraction pattern for aluminum samples and the probable formation of body-centered cubic diamond and hexagonal carbon in copper samples. The average grain sizes of Al4C3 were calculated ~40 nm for Al and ~35 nm for Cu. Mass spectra from a graphite hollow cathode duoplasmatron ion source are also presented. Atomic force microscopy images of a Cu sample also support the existence of 46 nm structures. Light carbon nanoparticles are readily available from the ion source in which a special carbonaceous environment creates regenerative soot. Support gas Ar produces more C3 than Ne.  相似文献   
169.
An overview of analytical and numerical methods for prediction of residual stresses in thermal spray coatings is presented. The various sources and mechanisms underlying residual stress development in thermal spray coatings are discussed, then the various difficulties associated with experimental residual stress measurement in thermal spray coatings are highlighted. The various analytical and numerical models used for prediction of residual stresses in thermal spray coatings are thoroughly discussed. While analytical models for prediction of postdeposition thermal mismatch stresses are fully developed, analytical quenching and peening stress models still require extensive development. Various schemes for prediction of residual stresses using the finite element method are identified. The results of the various numerical and analytical models are critically analyzed, and their accuracy and validity, when compared with experiments, are discussed. Issues regarding the accuracy and applicability of the models for predicting residual stresses in thermal spray coatings are highlighted, and several suggestions for future development of the models are given.  相似文献   
170.
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