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61.
The initial nucleation and growth characteristics of amine layers photochemically attached from 10-amino-dec-1-ene molecules protected with tri-fluoroacetic acid group to H-terminated undoped single crystal CVD diamond surfaces are characterized by tapping and contact mode atomic force microscopy (AFM) and scanning tunneling microscopy (STM) with nanometer resolution. The diamond is atomically flat which allows attributing variations of tunneling currents in STM to amine grafted surface areas. Island formation and growth of islands with increasing photochemical attachment time is revealed by these experiments. This results support the growth model, where hydrogen cleavage reactions from the diamond surface by amine molecules bonded to diamond is the major growth mechanism. These reactions might be initiated by UV light illumination of pyrolysis of organic peroxides in the presence of the adsorbate, which are proposed to break H–C bonds to create surface dangling bonds. It occurs at the periphery of islands which gives rise to island growth.  相似文献   
62.
Plants attacked by insect herbivores release a blend of volatile organic compounds (VOCs) that serve as chemical cues for host location by parasitic wasps, natural enemies of the herbivores. Volicitin, N-(17-hydroxylinolenoyl)-l-glutamine, is one of the most active VOC elicitors found in herbivore regurgitants. Our previous study revealed that hydroxylation on the 17th position of the linolenic acid moiety of N-linolenoyl-l-glutamine increases by more than three times the elicitor activity in corn plants. Here, we identified N-(18-hydroxylinolenoyl)-l-glutamine (18OH-volicitin) from larval gut contents of tobacco hornworm (THW), Manduca sexta. Eggplant and tobacco, two solanaceous host plants of THW larvae, and corn, a non-host plant, responded differently to this new elicitor. Eggplant and tobacco seedlings emitted twice the amount of VOCs when 18OH-volicitin was applied to damaged leaf surfaces compared to N-linolenoyl-l-glutamine, while both these fatty acid amino acid conjugates (FACs) elicited a similar response in corn seedlings. In both solanaceous plants, there was no significant difference in the elicitor activity of 17OH- and 18OH-volicitin. Interestingly, other lepidopteran species that have 17OH-type volicitin also attack solanaceous plants. These data suggest that plants have developed herbivory-detection systems customized to their herbivorous enemies.  相似文献   
63.
From the fission yeast Schizosaccharomyces pombe we have identified and deleted vps33, a gene encoding a homologue of VPS33, which is required for vacuolar biogenesis in S. cerevisiae cells. When the vps33(+) gene is disrupted, Sz. pombe strains are temperature-sensitive for growth and contain numerous small vesicular structures stained with FM4-64 in the cells. Deletion of the Sz. pombe vps33(+) gene results in pleiotropic phenotypes consistent with the absence of normal vacuoles, including missorting of vacuolar carboxypeptidase Y, various ion- and drug-sensitivities, and sporulation defects. These results are consistent with Vps33p being necessary for the morphogenesis of vacuoles and subsequent expression of vacuolar functions in Sz. pombe cells.  相似文献   
64.
We prepared emulsions and capsules that were stabilized by wool powder particles. These powder particles were adsorbed on oil-water interfaces, and they formed both oil-in-water and water-in-oil emulsions. These emulsions were observed in ternary systems containing silicone oil, n-dodecane, fluoric oil, oleic acid, or linoleic acid as the oil phase.  相似文献   
65.
In the face of worsening environmental problems, the manufacturing industry is required to reduce resource consumption and environmental loads during product life cycles while responding to diversified user needs without cost increases. In this paper, we propose a reconfiguration method to remanufacture a variety of products using modules extracted from returned products of multiple generations for responding to varied user needs. With this method, we can maximize the sales amount of remanufactured products, which meet the performance requirements of each user group. We demonstrate the effectiveness of the method by applying it to photocopiers.  相似文献   
66.
Discrete fracture network (DFN) models have been proved to be effective tools for the characterisation of rock masses by using statistical distributions to generate realistic three-dimensional (3D) representations of a natural fracture network. The quality of DFN modelling relies on the quality of the field data and their interpretation. In this context, advancements in remote data acquisition have now made it possible to acquire high-quality data potentially not accessible by conventional scanline and window mapping. This paper presents a comparison between aggregate and disaggregate approaches to define fracture sets, and their role with respect to the definition of key input parameters required to generate DFN models. The focal point of the discussion is the characterisation of in situ block size distribution (IBSD) using DFN methods. An application of IBSD is the assessment of rock mass quality through rock mass classification systems such as geological strength index (GSI). As DFN models are becoming an almost integral part of many geotechnical and mining engineering problems, the authors present a method whereby realistic representation of 3D fracture networks and block size analysis are used to estimate GSI ratings, with emphasis on the limitations that exist in rock engineering design when assigning a unique GSI value to spatially variable rock masses.  相似文献   
67.
The influences of soaking treatment and storage conditions on the softening of cooked beans, namely, soybeans and red kidney beans, were investigated. It was revealed that the softening of fresh soybeans and fresh red kidney beans was suppressed during subsequent boiling after soaking treatment at 50 and 60 °C. Furthermore, in treated aged soybeans and red kidney beans that were subjected to storage at 30 °C/75% relative humidity for 6 mo and soaking treatment at 50 to 60 °C, the hardness during cooking was further amplified. This suggested that the mechanism of softening suppression differs depending on the influences of soaking and storage. Analysis of the pectin fraction in alcohol insoluble solid showed insolubilization of metal ions upon storage at high temperature and high humidity in both soybeans and red kidney beans, which suggests interaction between Ca ions and hemicellulose or cellulose as cell wall polysaccharides. The results of differential scanning calorimetry (DSC) showed that aged soybeans exhibited a shift in the thermal transition temperature of glycinin‐based protein to a higher temperature compared with fresh soybeans. From the results of DSC and scanning electron microscopy for aged red kidney beans, damaged starch is not conspicuous in the raw state after storage but is abundant upon soaking treatment. As for the influence of soaking at 60 °C, it can be suggested that its influence on cell wall crosslinking was large in soybeans and red kidney beans in both a fresh state and an aged state.  相似文献   
68.
69.
Fatty acid amides (FAAs) are known elicitors that induce plants to release volatile compounds that, in turn, attract foraging parasitoids. Since the discovery of volicitin [N-(17-hydroxylinolenoyl)-l-glutamine] in the regurgitant of larval Spodoptera exigua, a series of related FAAs have been identified in several other species of lepidopteran caterpillars. We screened 13 non-lepidopteran insects for the presence of FAAs and found that these compounds were present in adults of two closely related cricket species, Teleogryllus taiwanemma and T. emma (Orthoptera: Gryllidae), and larvae of the fruit fly, Drosophila melanogaster (Diptera: Drosophilidae). When analyzed by liquid chromatography/mass spectrometry-ion trap-time-of-flight (LCMS-IT-TOF), the gut contents of both crickets had nearly identical FAA composition, the major FAAs comprising N-linolenoyl-l-glutamic acid and N-linoleoyl-l-glutamic acid. There were also two previously uncharacterized FAAs that were thought to be hydroxylated derivatives of these glutamic acid conjugates, based on their observed fragmentation patterns. In addition to these four FAAs containing glutamic acid, N-linolenoyl-l-glutamine and a small amount of volicitin were detected. In D. melanogaster, N-linolenoyl-l-glutamic acid and N-linoleoyl-l-glutamic acid were the major FAAs found in larval extracts, while hydroxylated glutamic acid conjugates, volicitin and N-linolenoyl-l-glutamine, were detected as trace components. Although these FAAs were not found in ten of the insects studied here, their identification in two additional orders of insects suggests that FAAs are more common than previously reported and may have physiological roles in a wide range of insects besides caterpillars.  相似文献   
70.
Surface modified polyethylene (g‐PE), PMPC‐g‐PE, PGEMA‐g‐PE, PNIPAAm‐g‐PE and PHPMA‐g‐PE films with the water soluble polymers such as poly[2‐(methacryloyloxy)ethyl phosphorylcholine] (PMPC), poly[2‐(glucosyloxy)ethyl methacrylate] (PGEMA), poly(N‐isopropylacrylamide) (PNIPAAm) and poly[N‐(2‐hydroxypropyl) methacrylamide] (PHPMA) were prepared by graft copolymerization using an Ar plasma‐post polymerization technique. The surface of the g‐PE films was characterized by means of X‐ray photoelectron spectroscopy and the grafting percentage of PMPC, PNIPAAm and PHPMA was found to be 5.31, 2.83, and 3.40% for the corresponding g‐PE film. Biocompatibility of the g‐PE films was evaluated by the adsorption of serum proteins and the Michaelis constant (Km) for the enzymatic reaction of thrombin with synthetic substrate S‐2238 in the presence of g‐PE film. The biocompatibility of water soluble polymers such as PMPC, polyoxyethylene (POE), PGEMA, PNIPAAm and PHPMA was also evaluated by the same enzymatic reaction of thrombin with S‐2238 in their polymer solutions. The Km values in the presence of water soluble polymers was found to decrease in the order PMPC > POE > PGEMA > PNIPAAm > PHPMA. As a conclusion, PMPC‐g‐PE film exhibited the most biocompatibility among g‐PE films because its surface adsorbed less protein than those of the untreated PE and other g‐PE films and it showed the largest Km for the enzymatic reaction.  相似文献   
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