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31.
A study of user experiences mediated by nomadic web content in a museum   总被引:4,自引:0,他引:4  
Abstract How should nomadic web content be designed to improve and transform user experiences in a hands‐on museum? In this study, 15 users were studied while using an electronic guidebook designed to augment user experiences via wireless technologies at the Exploratorium, an interactive science museum. Several recurring themes emerged from the analysis, such as users' sense of isolation and users' attempts to make a seamless transition between real‐place and virtual contexts. This paper shares a preliminary framework for organising user interactions with handheld devices, user experiences based on interviews and insights regarding the role of nomadic web content.  相似文献   
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Low-temperature co-fired ceramics (LTCCs) that are composed of a RuO2-based resistor and a cordierite–glass substrate have been sintered at temperatures of 850° and 900°C. The microstructure of the resistor/substrate interface has been investigated using scanning and transmission electron microscopy, and its correlation to the overall resistance has been discussed. X-ray diffractometry has revealed that lead ruthenate pyrochlore (Pb2Ru2O6.5) in peak-fired thick-film resistors (TFRs) disappears and the co-fired samples contain only RuO2 in the resistor film when sintered at 900°C. The overall resistance of the LTCC resistors is increased by a factor of ∼3 when temperature is increased from 850°C to 900°C. The cordierite–glass composition of the initial substrate reacts with glass in the resistor film. The greatly extended layer of the resistor/substrate interface that contains the conductor particles is either broad or diffuse, which contrasts the abrupt interface that often is observed in conventional TFRs. This layer contains predominantly faceted platelike crystals of anorthite, in addition to other phases (such as diopside, sapphirine, and cristobalite) that apparently crystallize during co-firing as vitrification and chemical reactions between glass compositions of the substrate and the resistor occur. The increase in the resistance of the LTCC resistors is attributed to the interruption of the conducting path by platelike anorthite crystals that are produced in the resistor/substrate interface when subjected to co-firing.  相似文献   
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Surface‐assisted laser desorption/ionization mass spectrometry (SALDI‐MS) represents a powerful tool for the analysis of biomolecules, synthetic polymers, and even small organic compounds; its performances largely depend on the type of matrix materials utilized. Here, for the first time the employment of nanoporous carbons derived from metal‐organic frameworks (MOFs) as novel matrices for SALDI‐MS is demonstrated. The nanoporous carbons derived from MOFs not only circumvent the shortcomings of existing matrix materials but also demonstrate much higher efficiency of laser desorption/ionization for various compounds than any other nanoporous carbons reported so far. A new perspective for the development of matrix materials for SALDI‐MS application is therefore provided.  相似文献   
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Control and selection of the properties of active pharmaceutical ingredients is a crucial part of the drug development process. One major part of this process is the selection of an appropriate solid form. This review will discuss three major types of crystalline solids, polymorphs, salts and cocrystals and processes used to develop and find these forms.  相似文献   
36.
Vascular remodeling in the brain occurs as a plastic change following neural over‐activity. The auditory midbrain (or inferior colliculus, IC) is an ideal place to study sound‐induced vascular changes because it is the brain's most vascularized structure and it is tonotopically organized. However, its micro‐vascular pattern remains poorly understood. Since the IC is a sphere‐like structure, the histological assessment of vasculature could depend on the angle of sectioning. Here, we studied the effects of cutting the IC at different angles on microvascular assessment, specifically: micro‐vascular density and the shape of microvascular lumen. Photomicrographs were taken from 5 µm toluidine blue‐stained histological sections obtained at two angles of sectioning: (a) the conventional coronal sectioning, and (b) a novel “tangential” sectioning (tangential to the dorso‐medial surface of the IC). Results showed that the tangential sections, in comparison with the coronal sections, yielded (a) a higher count of micro‐vascular density and (b) a higher proportion of round‐shaped micro‐vascular lumens. This discrepancy in results between two cut angles is likely related to the spatial pattern of blood vessels supplying the IC. We propose that the tangential sectioning should be adopted as standard for the accurate study of microvasculature in the IC. Microsc. Res. Tech. 78:105–110, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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The Proteus architecture is a highly parallel, multiple instruction, multiple data machine (MIMD) optimized for large granularity tasks such as machine vision and image processing. The system can achieve 20 gigaflops (80 gigaflops peak). It accepts data via multiple serial links at a rate of up to 640 MB/S. The system employs a hierarchical reconfigurable interconnection network with the highest level being a circuit-switchedenhanced hypercube, serial interconnection network for internal data transfers. The system is designed to use 256 to 1024 RISC processors. The processors use 1-MB externalread/write allocating caches for reduced multiprocessor contention. The system detects, locates, and replaces faulty subsystems using redundant hardware to facilitatefault tolerance. The parallelism is directly controllable through an advanced software system for partitioning, scheduling, and development. System software includes a translator for the INSIGHT language, a parallel debugger, lowand high-level simulators, and a message-passing system for all control needs. Image-processing application software includes a variety of point operators, neighborhood operators, convolution, and the mathematical morphology operations of binary and gray-scale dilation, erosion, opening, and closing.  相似文献   
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Early estimation of the wiring space requirements for logic chips and chip-carrying packages is essential. The authors propose a way to do this by taking into account the average length of wiring connections, the number of logic units to be wired, and the average number of connections per logic unit. They show that the probability of automatic wiring success is a function of the number of wiring tracks per logic unit, and that logic changes during design and the use of multicell macros increase the required track count. Intentional depopulation of the image, on the other hand, and the use of multilevel metal wiring decrease the required track count and chip size, respectively, for fixed maximum circuit cell count and fixed probability of automatic wiring success.  相似文献   
40.
f-channel nucleotide modulation was investigated in sino-atrial (SA) node cells isolated from rabbit hearts, using an inside-out macropatch configuration. Saturating doses (30 microM) of phosphorothioate derivatives of cAMP, Sp-cAMPS and Rp-cAMPS, were tested on the cAMP-induced shift of I(f) activation. Responses were not altered when Sp-cAMPS was combined with cAMP. When Rp-cAMPS was superfused with subsaturating cAMP concentrations (1-10 microM), it inhibited cAMP-induced I(f) activation shift. cGMP and cIMP reversibly shifted the I(f) conductance-voltage curve to more positive values; however they had a lesser specificity than that of cAMP. The efficacy ranking for I(f) activation by cyclic nucleotides was: cAMP > cGMP > cIMP. Non cyclic nucleotides (ATP, ADP and AMP) failed to change I(f) activation, indicating that the cyclic nature of nucleotides seems to be essential to f-channel modulation. Similarities between f-channels and cyclic nucleotide-gated (CNG) channels are discussed.  相似文献   
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