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The frequent evocative comparisons between music and architecture in the text of the Modulor may explain why Le Corbusier, in this constant search for ordering principles, considered his proportional sequence to be equivalent to a musical scale. Yet, since the dimensional ratios of Le Corbusier’s ‘scale’ are much larger than the pitch ratios of the latter, the Modulor comes much closer to another structural element of music, that of harmony. By adjusting the Modulor ratios to the corresponding ratios of musical chords, three variants of a “musical” Modulor can be generated – Chromatic, Major and Minor. If, in addition, the two sets of the malebased Modulor dimensions are replaced with a universal female-male set, the inherently complex Modulor numbers become simpler and clear. The Master’s intention of producing a rational and practical system of proportions, which is related to both the scale of the human being, and to the order inherent in the physical nature of sound, can thus be realized.  相似文献   
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Water is known as one of the main transmission routes of Campylobacter and contributes to increase the number of sporadic infections and outbreaks. Campylobacter jejuni persists in the environment, especially in water, in a viable but non-culturable (VBNC) form that is thought to be a possible cause of water-borne outbreaks. In this study, we evaluated the loss of culturability and viability of 9 C. jejuni strains of clinical origin and one ATCC reference strain when kept at 4 degrees C in artificial sea water (ASW). Culturability was measured as colony-forming units while viability was evaluated by CTC-DAPI double staining and the combined CTC-specific fluorescent antibody technique (CTC-FA). When cultured on Columbia Agar plates, strains exhibited different growth profiles which allowed to classify them into three different groups. Both techniques used to monitor the viability of the bacterial cells showed that C. jejuni strains survived in the VBNC form in the microcosms through a period lasting from 138 to 152 days. The recovery of C. jejuni VBNC forms to culturability, as evidenced by cell division, was obtained by passage in the mouse intestine. Our results indicate that C. jejuni VBNC cells were able to remain in this state for a few months and regain their culturability after in vivo passage depending on their lasting in the VBNC state, which affects the number of respiring bacteria. In fact, the resuscitation was achieved when the number of respiring bacteria became higher than 10(4) cell/ml. Therefore, a relatively high microbial titer of respiring bacteria in the VBNC state seems to be important for the resuscitation and subsequent intestinal colonisation.  相似文献   
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Remarkably, a number of definitive epithelia, such as that of the anterior lens, give rise when suspended within 3D gels of type I collagen, to elongate, bipolar shaped cells that exhibit the ultrastructure, polarity, and migratory ability of mesenchymal cells. They begin producing type I collagen and stop producing crystallins, type IV collagen, and laminin. Here, we investigated changes in beta 1 integrins and their extracellular matrix (ECM) ligands during this transdifferentiation. The former free surface of the lens epithelium that is now in contact with collagen begins within a day to stain intensely for beta 1 and it is this surface rather than the surface facing the basement membrane that gives rise to mesenchymal cells. Immunoprecipitation experiments reveal a large increase in the beta 1 integrin subunit on mesenchymal cells as compared to the epithelium of origin. The alpha 5 integrin subunit, which is barely detectable in the lens, increases in the mesenchymal cells and alpha 3 continues to be expressed at about the same level as in the epithelium. alpha 6, the epithelial integrin subunit, and laminin, its ECM ligand, are not detected immunohistochemically or biochemically in the mesenchyme. Rather, the mesenchymal cells secrete abundant fibronectin, the major ECM ligand for alpha 5 beta 1. RGD peptides do not inhibit the transformation but antibodies to beta 1 do perturb the emigration of mesenchymal cells from the lens apical surface. We conclude that the beta 1 integrins newly expressed on the apical epithelial surface interact with the surrounding 3D collagen gel to help bring about this unusual epithelial-mesenchymal transition.  相似文献   
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The effects of ion implantation and subsequent annealing on the surface morphology of thin amorphous chalcogenide films of the As-Se system have been studied. Ion implantation of nitrogen (N+) with an energy E=100 keV and high doses (typically D=1.1016 cm−2) has been carried out at room temperature. Subsequent thermal annealing treatments near the melting temperature (Tg∼160°C) have been performed leading to changes in the thin-film morphology, which are dependent on the As content and are best expressed for the As3Se2 films. Optical microscope photographs reveal details of the rippled surface exhibiting quasi-regular domain-like structure. The parameter λ, describing it, is dependent on the film thickness and grows with its increase. Thermal annealing near Tg also influences the diffuse optical reflectivity—it increases considerably while the interference features tend to disappear with the appearance of the rippled film surface structure and the effect is again greater for the thicker films.  相似文献   
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Lactic acid bacteria (LAB) from Ciauscolo salami produced in Marche Region of Central Italy, and LAB strains belonging to our laboratory collection were examined for their capability to survive at low pH and bile, to adhere to Caco-2 cells, and for antibiotic resistance. LAB from Ciauscolo were identified by ARDRA and RAPD-PCR. Our study showed that all LAB strains had good adaptation to gastric juice and moderate tolerance to bile. The adhesiveness was variable among strains but significantly lower in LAB from food. Antibiotic resistance was broadly spread among food strains, with level of resistance exceeding 15% for all the antibiotics tested. The resistance determinants erm(B) and tet(M) were found in nine strains of food origin (21.4%) while tet(L) in one strain of our collection (5%). Our work suggests that fermented foods are valuable sources of bacterial strains with functional traits of intestinal lactobacilli. These bacteria may be further studied for their use in probiotic applications.  相似文献   
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Cellulose–poly(glycidyl methacrylate) graft copolymer (CPGMA) was treated with ammonia (AH), ethylamine (EA), diethylamine (DEA), and triethylamine (TEA). Factors affecting the reaction, such as reaction duration, temperature, liquor ratio, pH, and aminating agent/epoxide molar ratio were studied. A mechanism of the reaction was suggested. The anion exchange celluloses were characterized by studying its capacity, potentiometric titration, and durability to use. Potentiometric titration of the produced anion exchangers has been studied and pKb values were found to be 6.1, 7.6, and 8.9 for DEA–CPGMA, EA–CPGMA, and AH–CPGMA, respectively.  相似文献   
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The phase evolution occurring during the reaction between corrosive V2O5 (Tm = 690 °C) and a plasma-sprayed 7 wt.% Y2O3–ZrO2 (YSZ) coating from 700 to 900 °C has been investigated in situ by X-ray diffraction. The temperature and time of interaction between the V2O5 and YSZ coating determines the phases observed. Between 700 and 750 °C, reaction products of ZrV2O7 and YVO4 were observed within minutes of reaching the test temperature. m-ZrO2 was observed after 220 and 60 min at 700 and 750 °C, respectively. The simultaneous formation of both ZrV2O7 and YVO4 at the beginning of the reaction along with the delay of the m-ZrO2 formation suggests similar reactivity between both Zr and Y with V2O5. The weight percent of the ZrV2O7 phase began to diminish after 150 and 60 min at 700 and 750 °C, respectively. For reaction temperatures of 800 and 900 °C, there is a rapid decrease in the amount of t′-ZrO2 and a rapid increase in the amount of m-ZrO2 with reaction time. YVO4 was also observed at these reaction temperatures. SEM and TEM microstructural observations confirmed the phases detected from the in situ XRD experiments. Reactions between YSZ and V2O5 suggest that the formation of a liquid phase due to the high solubility of both zirconia and yttria in vanadia is the dominate mechanism that damages the coating. The thermal conductivity of a plasma-sprayed YSZ coating reacted with up to 1 wt.% V2O5 did not significantly change due to the small volume affected.  相似文献   
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