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41.
Self-incompatibility (SI) is conserved among members of the Brassicaceae plant family. This trait is controlled epigenetically by the dominance hierarchy of the male determinant alleles. We previously demonstrated that a single small RNA (sRNA) gene is sufficient to control the linear dominance hierarchy in Brassica rapa and proposed a model in which a homology-based interaction between sRNAs and target sites controls the complicated dominance hierarchy of male SI determinants. In Arabidopsis halleri, male dominance hierarchy is reported to have arisen from multiple networks of sRNA target gains and losses. Despite these findings, it remains unknown whether the molecular mechanism underlying the dominance hierarchy is conserved among Brassicaceae. Here, we identified sRNAs and their target sites that can explain the linear dominance hierarchy of Arabidopsis lyrata, a species closely related to A. halleri. We tested the model that we established in Brassica to explain the linear dominance hierarchy in A. lyrata. Our results suggest that the dominance hierarchy of A. lyrata is also controlled by a homology-based interaction between sRNAs and their targets.  相似文献   
42.
An analytical method was developed for determination of residual avoparcin in chicken muscle by measuring alpha- and beta-avoparcin, major components of the pharmaceutical preparation avoparcin, using HPLC with UV and amperometric detectors. The analytical HPLC was run on a Cosmosil 5C18-AR column (4.6 mm x 25 cm) with a gradient formed from A: 2.5% acetic acid, 0.01 mol/L sodium heptane sulfonic acid-acetonitrile (88.5:11.5) (pH 4.0) and B: 2.5% acetic acid-acetonitrile (10:90), using UV and amperometric detection (AMD) with glassy-carbon electrode (+900 mV). Avoparcin was extracted from chicken muscle by homogenization with methanol-0.2 mol/L sulfuric acid (6:4) followed by centrifugation after pH adjustment to 4 with 1 mol/L sodium hydroxide. The supernatant was evaporated to dryness, and the residue was dissolved in water. The aqueous layer was adjusted to pH 4 by adding 1 mol/L sodium hydroxide. Then it was purified on a Sep-Pak tC18 plus ENV cartridge. The cartridge was washed with water, and retained substances were eluted with 50% methanol. The eluate was evaporated to dryness under reduced pressure. The residue was dissolved in water and determined by HPLC. Recoveries of avoparcin spiked in chicken muscle were 73.1-88.1% at levels of 2-10 micrograms/g. The detection limits were 0.5 microgram/g (UV) and 0.2 microgram/g (AMD).  相似文献   
43.
The structural organization and fine distribution of the lymphatic networks in the periodontal tissues (gingiva, periodontal membrane, and alveolar process) and dental pulp of animals and humans were reviewed with special reference to histochemical examination by light and electron microscopy. The distinction between lymphatics and blood vessels was made on cryostat sections of undecalcified and calcified teeth treated with EDTA solution and whole mount preparations of periodontal membranes using 5'-nucleotidase (5'-Nase)-alkaline phosphatase (ALPase) double staining. This staining procedure allowed lymphatic vessels in the periodontal tissue and dental pulp to be differentiated from blood vessels. The specificity and localization of the enzyme reactions were confirmed by comparative histochemical studies of the same specimen with light microscopy and scanning or transmission electron microscopy. Well-developed 5'-Nase-positive lymphatic networks were observed on the tissue sections and whole mount preparations of the gingiva, periodontium, and dental pulp. More lymphatic vessels were seen in the root area of the periodontium than in the cervical area. In the dental pulp, lymphatic vessels were more numerous in the central part than in the peripheral odontoblastic layer. These distributions of the lymphatic capillary networks are discussed in relation to their ability to supply lymph to the teeth.  相似文献   
44.
This paper describes a 32-Mb embedded DRAM macro fabricated using 0.13-μm triple-well 4-level Cu embedded DRAM technology, which is suitable for portable equipment of MPEG applications. This macro can operate 230-MHz random column access even at 1.0-V power supply condition. The peak power consumption is suppressed to 198 mW in burst operation. The power-down standby mode, which suppresses the leakage current consumption of peripheral circuitry, is also prepared for portable equipment. With the collaboration of array circuit design and the fine Cu metallization technology, macro size of 18.9 mm2 and cell efficiency of 51.3% are realized even with dual interface and triple test functions implemented  相似文献   
45.
At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However, at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity. This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage loss, and additional design effort.
Xiaoqing WenEmail:
  相似文献   
46.
The molecular alignment of polydiacetylene (PDA) derivatives and their optical and electrical properties of thin films based on PDA derivatives have been studied. The PDA derivatives were aligned depending on the direction of applied shear stress in the film. From measurements of the polarized absorption and current–voltage characteristics, the optical and electrical anisotropies have been observed, that was discussed by taking the PDA main chain alignment into consideration.  相似文献   
47.
Solid oxide fuel cells (SOFCs) are very attractive for their high energy conversion efficiency and low emissions. Generally, a supported layer of SOFCs is fabricated by tape casting, using an organic solvent. Recently, a slurry based on water instead of an organic solvent has been sought in order to avoid environmental pollution. In this study, the anode of SOFCs was fabricated by aqueous tape casting, and the electrolyte and the cathode were deposited by screen printing. The I–V characteristics of the cell thus obtained were evaluated. As a result, an 80 mm diameter-sized cell with a power density of 0.33 W/cm2 at 800 °C was successfully fabricated by controlling sintering conditions.  相似文献   
48.
A calcium phosphate glass-ceramic crown for dentistry was developed. The glass is cast into the shape of the crown by the lost-wax technique and subsequently heat-treated to convert it into the glass-ceramic, which exhibits excellent mechanical strength. The fine structure of the glass-ceramic is similar to that of the enamel of a natural tooth, and its hardness is near that of enamel.  相似文献   
49.
Seiji Isoda 《Polymer》1984,25(5):615-624
When poly(p-xylylene) is synthesized from gaseous monomers, it grows epitaxially on substrates. The effects of the substrate and annealing on the epitaxy are examined by growing the polymer on cleavage (001) surfaces of four kinds of alkali halides (NaCl, KCl, KBr and Kl). The polymer crystallizes with its chains oriented along the 〈100〉 and 〈010〉 directions of the substrates and the faster growth planes are parallel to the (001) plane of substrate, i.e., the (010) plane of the α-form crystal and the (100) plane of the β-form. The degree of orientation is the highest on KBr and the lowest on NaCl. The lattice matching requirement is important in the epitaxial synthesis. The observed orientation of the polymer chain on each substrate is compared with the orientation expected from a minimum of interfacial potential energy calculated on the basis of dispersion-repulsive forces between atoms in the polymer and ions in the substrate. The orientational angle of polymer chain on the substrates and the degree of its orientation are qualitatively explained in terms of the processes of monomer deposition, polymerization and crystallization under the directive influence of the substrate.  相似文献   
50.
A cylindrical ionophore (1) in which two diaza-crown ethers are linked by two azobenzene pillars serves as a photoresponsive host molecule. In alkaline solution containing K+, (1) forms a cascade complex with dianionic guest molecules, but photoirradiated (1) which has a shortened cylinder cannot bind the guest molecules so effectively as (1). (1) solubilised in acidic aqueous solution by protonation of four tertiary nitrogens provides a hydrophobic cavity to bind several anionic azo dyes. The association is also suppressed by photoirradiation. The results indicate that parallel array of the azobenzene segments in (1) provides a host cavity and the photoinduced structural change is readily reflected by the association tendency. This is the first example for the photoresponsive inclusion complex.  相似文献   
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