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The physico-chemical and biochemical properties of the raw pork products, spontaneously fermented as entire primal cuts of ham hock (raw smoked ham hock (RSR)) and loin (raw smoked loin (RSL)), were estimated during the 4-week ripening period. A decrease in water content (4 % in RSR and 7 % in RSL) and an increase in protein (2 and 4.5 %, respectively), fat and salt content (1–2 % for both products) were associated with the phenomena of slight drying. An almost 2.5-fold increase of free amino groups dissolved in water, from 480 to 1,100 μMGly/100 g and from 490 to 1,200 μMGly/100 g, accompanied by a gradual increase of total free fatty acids, from 250 to 530 mg/kg and from 270 to 460 mg/kg, was indicated in the RSR and RSL, respectively. The fermentation and accumulation of free fatty acids affected the pH decrease in the RSL, particularly with a low fat content. The increase of tyramine, tryptamine, putrescine and spermine amounts confirm the activity of bacteria strains in the RSR and RSL during ripening. The considerable part of the “house microflora” included the species fermenting in the presence of air or in anaerobic conditions—in the presence of nitrogen. The presence of volatile cell metabolism products (3-hydroxy-2-butanone, 3-methyl-1-butanol and butanoic acid) confirmed a greater amino acid transformation and saccharide fermentation activity of microflora in the RSR. Similarly, products of free fatty acid degradation (pentanal, hexanal and butanoic acid) as well as products of lipid oxidation (e.g. 3-methyl-3-buten-1-ol and 3-methyl-1-butanol) confirmed the far advanced ripening in the RSR with a greater fat content.  相似文献   
53.

The objective of the study was to define the primary environmental factors affecting the composition of the macrobenthic community in an abandoned open cast sulphur mine pit lake that had been filled with water from a nearby river. We investigated habitats at various depths and the macrobenthic communities; samples were collected by scuba divers. Although rush and submerged vegetation in the subsaline pit lake was abundant and provided potentially good habitat conditions for mayflies, caddisflies, coleopterans, or damselflies, the native insects were scarce. The taxa do not have many representatives in waters with elevated salinity, so those present in the Machów pit lake were mainly euryhaline species. Chironomids were the most abundant macroinvertebrates in shallower zones, whereas non-native zebra mussels were the quantitatively dominant taxon in deep-water zones. Moreover, these non-native mussels were the dominant biomass of invertebrates at all sites in all seasons. The current composition of the invertebrate assemblage was probably primarily determined by the salinated water, which limited the abundance of native species and gave non-native species an edge.

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A murine monoclonal antibody (MAb) with human CD4 specificity was tested for the ability to inhibit primary human immunodeficiency virus type 1 (HIV-1) isolates clades A through E. Human peripheral blood mononuclear cells (PBMC) were used as target cells for infectivity. The HIV-1 primary isolates were examined for the capacity to infect PBMC targets in the presence or absence of the anti-CD4 MAb, designated P1. P1 broadly inhibited clade A, C, D, and E isolates, based on a reduction of HIV-1 p24 antigen concentrations compared with untreated controls. Little to no virus-inhibiting activity was observed with a primary HIV-1 clade B isolate, designated BZ167. Additionally, a second primary clade B isolate was efficiently inhibited from infecting PBMC targets by P1. The data indicate that P1 exhibits group-specific inhibiting activity against non-clade B primary HIV-1 isolates in vitro.  相似文献   
56.
BACKGROUND: B-lymphocytes play an important part in the allergic reaction as producers of IgE antibodies. OBJECTIVE: To investigate the cell surface expression of the activation antigens CD23, CD40 and HLA-DR on B-lymphocytes in birch pollen allergic patients before and during birch pollen season and to study the effect of immunotherapy. METHODS: The study included 24 birch pollen allergic patients half of whom were treated with immunotherapy against birch pollen before the start of the season. Eleven of the 24 patients had asthma. Blood samples were taken and lung function was registered before the season began and before the immunotherapy treatment in January to February and during the season in May. The relative number of B-lymphocytes (CD19+) of the lymphocyte population and the cell surface expression of CD23, CD40 and HLA-DR on B-lymphocytes was measured by the use of flow cytometry. RESULTS: In the control group of patients the relative number and concentration of B-lymphocytes, the cell surface expression of CD23, CD40 and HLA-DR on B cells, and the serum concentration of IgE increased during season compared with before season. In contrast, in the immunotherapy treated patients no changes in the number of B cells or cell surface expression of CD23, CD40 and HLA-DR were demonstrated. CONCLUSION: The elevated expression of CD23, CD40 and HLA-DR on B cells, combined with increased levels of IgE in allergic patients during season could be explained by the effect of cytokines produced by activated TH2 cells. A shift from TH2 to TH1 cells might be the mechanism after the absence of signs of B-cell activation in immunotherapy treated patients. The prevention of increased cell surface expression on B cells by immunotherapy may constitute a significant mechanism behind the beneficial effects of immunotherapy in the treatment of pollen atopy.  相似文献   
57.
A photoelectron spectrum is reported for an anionic complex of uracil (U) with HCN. The effects of electron attachment to a complex of U with HA (A = CN, NC) have been studied at the density functional theory level with 6–31++G** basis sets and the B3LYP and MPW1K exchange correlation functionals. Critical anionic structures have been reexamined at the MP2/6–31++G** level. The B3LYP gas-phase deprotonation enthalpies are equal to 14.56, 15.13, and 15.12 eV for HNC, HCN, and H2S, respectively. The experimental deprotonation enthalpies are 15.217 ± 0.009 and 15.212 ± 0.126 eV for HCN and H2S, respectively. Hence, HCN and H2S have very indeed similar deprotonation enthalpies. The photoelectron spectra of anionic complexes of uracil with HCN and H2S are, however, very different. The (UHCN) spectrum reveals a broad feature with a maximum between 1.2–1.4 eV, whereas the main feature of the (UH2S) spectrum has a maximum between 1.7 and 2.1 eV. We suggest that barrier-free proton transfer (BFPT) occurs in the (UH2S)complex, but not in (UHCN). Critical factors for the occurrence of BFPT have been analyzed. The difference between the (UHCN) and (UH2S) complexes is attributed to differences in hydrogen bonds formed by HCN and H2S with uracil.  相似文献   
58.
In this paper, we investigate the problem of survivable all-optical routing in WDM networks with physical impairments. One of the recent key issues in survivable optical network design refers to maximization of the ratio of routeable demands while keeping the overall network cost low. In WDM networks, this goal can be achieved by routing as many demands in all-optical way as possible. Based on the latest technical trends driven by deployment costs, technical constraints, and backward compatibility, this will not mean that all demands will be routed in all-optical way in the near future. Nowadays, operators are mostly willing to dedicate only a given ratio of their power budget to all-optical routing. This in turn implies a new problem to be solved: operators have to find a way to select demands that should be routed in all-optical way and which should not. The problem gets even more complicated, if we add demand protection issues. In this paper, we introduce and evaluate methods able to maximize the number of demands routed with protection in all-optical way in capacity-constrained networks with limitations on path lengths according to physical impairments.  相似文献   
59.
Substantial improvement of electrical and optical properties of InGaN/GaN multiple quantum wells (MQWs) was obtained with a triangular band structure. Transmission electron microscopy (TEM) images from the–50 nm. The light-emitting diodes (LEDs) with the triangular QWs showed a lower operation voltage, a higher light output power, and higher intensities and narrower line widths of electroluminescence spectra than those with the rectangular QWs. Very bright and uniform light emission from the triangular MQW LEDs was also observed at a low injection current, but spatially non-uniform emission from the rectangular ones.  相似文献   
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