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In this paper, we present a digital library system for managing heterogeneous music collections. The heterogeneity refers to various document types and formats as well as to different modalities, e. g., CD-audio recordings, scanned sheet music, and lyrics. The system offers a full-fledged, widely automated document processing chain: digitization, indexing, annotation, access, and presentation. Our system is implemented as a generic and modular music repository based on a service-oriented software architecture. As a particular strength of our approach, the various documents representing aspects of a piece of music are jointly considered in all stages of the document processing chain. Our user interfaces allow for a multimodal and synchronized presentation of documents (WYSIWYH: what you see is what you hear), a score- or lyrics-based navigation in audio, as well as a cross- and multimodal retrieval. Hence, our music repository may be called a truly cross-modal library system. In our paper, we describe the system components, outline the techniques of the document processing chain, and illustrate the implemented functionalities for user interaction. We describe how the system is put into practice at the Bavarian State Library (BSB) Munich as a part of the German PROBADO Digital Library Initiative (PDLI).  相似文献   
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ABSTRACT

Initiatives to operationalize the concept of resilience in the building industry are rapidly emerging. The concept of resilience has introduced a way to explore solutions to some important problems in the building industry. However, much of the work that has taken place to date represents activities generally assigned to risk management, which is discussed as being inherently insufficient for sustaining the functions of the built environment under stresses. This commentary considers the opportunities and limitations for mainstreaming resilience into building industry processes and actors. Barriers include indeterminate analytical meaning, event and performance uncertainty, immature regulatory standards setting, and untested enterprise economics. Further, the multiple outcomes of recovery and the relationship between building recovery and adaptation are discussed and, along with economics of resilience investments, a research need highlighted. A simple heuristic is presented to illustrate the complement of resilience to risk management and advance the integration of resilience into existing industry workflows.  相似文献   
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The coating of fired clay substrates with various metal oxides, such as anatase, rutile, zinc oxide and tin oxide was achieved using a simple spraying technique followed by a thermal treatment. The photocatalytic activity of the layer was characterized through measurement of the absorption spectrum, in the range 400–800 nm, of methylene blue deposited on top of the coating. Results show that the presence of anatase enhances the degradation of methylene blue when it is exposed to ultraviolet light. Thermal treatment at 1050 °C transforms anatase crystals into thermodynamically stable rutile. This results in a decrease of the photocatalytic activity, which can be explained by increase of the grain size and by a difference in the crystal structure. Measurements of the photocatalytic activity of ZnO and SnO2 show that these two oxides also exhibit photocatalytic properties. In particular, ZnO is a promising alternative material to anatase.  相似文献   
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Propoxylation of lactitol [4-O-β-D -galactopyranosyl-D -glucitol] under alkaline conditions afforded poly(ether polyol)s (PEP) which have been characterized by their unsaturation content, alpha color, hydroxyl number, viscosity, hygroscopicity, and molecular weight distribution. The analogous sucrose-based PEP were prepared for comparison. Lactitol was found to require shorter reaction times and produced lighter-colored polyols than did sucrose. Polyols produced from lactitol displayed similar physical properties to sucrose-based PEP. Molecular weight analysis by GPC using the universal calibration method showed lactitol PEP to have polydispersities between 1.04 and 1.07. Negligible decomposition of lactitol during propoxylation was confirmed by 13C-NMR and GPC. 1H-NMR of trifluoroacetyl derivatives of lactitol PEP afforded secondary determination of Mn. In addition, rigid polyurethane foams (PURF) formulated with lactitol-, sucrose-, or commercial sucrose–glycerin-based polyols and PAPI 27 were prepared and characterized. Lactitol-based PURF were found to compare favorably with sucrose-based foams, displaying a density and compressive strength of 28.9 kg/m3 and 1.213 × 105 N/M2, respectively. © 1996 John Wiley & Sons, Inc.  相似文献   
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A variety of functional nanostructured organic/inorganic hybrid materials from the europium‐exchanged derivative of a Preyssler‐type polyoxometalate (POM), [EuP5W30O110]12?, and functional organic surfactants were prepared by the ionic self‐assembly (ISA) route. The effect of organic surfactants on the structure, photoluminescent, electrochemical and electrochromic properties of the POM anions was investigated in detail. All obtained hybrid materials are amphotropic, i.e., exhibit both thermotropic and lyotropic liquid‐crystalline phase behaviour. Investigations of their photophysical properties have shown that the interactions of the various surfactants with the polyanions influence the coordination environments and site symmetry of Eu3+ in different ways. The functional groups in the organic surfactants significantly influence the electrochromic properties and photoluminescence of POMs. Different from normal and pyridine‐containing complexes, no photoluminescence and no electrochromism were observed from the ferrocene‐containing complexes. This may be explained in view of charge transfer between the POM anion and the ferrocenyl group.  相似文献   
8.
Liu S  Volkmer D  Kurth DG 《Analytical chemistry》2004,76(15):4579-4582
An electrochemical sensor design for selective NO detection is presented based on a polyoxometalate (POM) cluster immobilized on an electrode through a polyelectrolyte matrix. It is suggested that the POM can electrocatalyze the reduction of NO. The reduction current is proportional to the NO concentration in the investigated concentration window ranging from 1 nM to 10 microM. The sensitivity of the device can be adjusted by the number of immobilized layers. The response to possible interfering reagents such as nitrate and nitrite can be controlled through the multilayer design. By a predominant negatively charged outer surface, the response to these ions is markedly reduced.  相似文献   
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The serine protease trypsin was converted into a site-specific protease which hydrolyzes peptides between dibasic residues. Trypsin exhibits a high S1 specificity for Arg and Lys residues. However, the S1' specificity of trypsin is very broad, with only a slight preference for hydrophobic residues in P1'. We replaced Lys60 with Glu and Asp to introduce a high specificity for basic residues into the S1' site of trypsin. Both mutations cause a dramatic increase in the S1' specificity for Arg and Lys as measured by acyl transfer reactions. In K60E, the preference for Arg increases 70-fold while the preference for P1'-Lys increases 12-fold. In contrast, the preferences for other P1' residues either decrease slightly or remain the same. Thus, K60E prefers P1'-Arg over most other P1' residues by 2 orders of magnitude. Similar results are obtained when P1' specificity is measured in peptide cleavage assays. K60D exhibits an S1' specificity profile very similar to that of K60E, although the P1'-Arg preference is reduced by a factor of 2.5. Molecular modeling studies suggest that the high S1' specificity for Arg in K60E may be due to the formation of a salt bridge between Glu60 and the P1'-Arg of the substrate.  相似文献   
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