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Jesús Tabero Author Vitae Daniel Mozos Author Vitae 《Integration, the VLSI Journal》2008,41(2):281-296
A novel technique is proposed for the management of a 2D reconfigurable device in order to get true hardware multitasking. We use a Vertex List Set to keep track of the free area boundary. This structure contains the best candidate locations for the task, and several heuristics are proposed to select one of them, based in fragmentation and adjacency. A Look-Ahead heuristic that anticipates the next known event is also proposed. A metric is used to estimate the fragmentation status of the FPGA, based on the number of holes and their shape. Defragmentation measures are taken when needed. 相似文献
123.
V.A. Chouliaras Author Vitae V.M. Dwyer Author Vitae Author Vitae J.L. Nunez-Yanez Author Vitae Author Vitae K. Nakos Author Vitae Author Vitae 《Integration, the VLSI Journal》2008,41(1):135-152
This work presents a detailed case study in customizing a configurable, extensible, 32-bit RISC processor with vector/SIMD instruction extensions for the efficient execution of block-based video-coding algorithms utilizing a proprietary co-design environment. In addition to the default Full-Search motion estimation of the MPEG-2 Test Model 5, fourteen fast ME algorithms were implemented in both scalar and vector form. Results demonstrate a reduction of up to 68% in the dynamic instruction count of the full search-based encoder whereas the fast motion estimation algorithms achieved a reduction in instruction count of nearly 90%, both accelerated via three 128-bit vector/SIMD instructions when compared to the scalar, reference implementation of the standard. We address in detail the profiling, vectorization and the development of these vector instruction set extensions, discuss in depth the implementation of a parametric vector accelerator that implements these instructions and show the introduction of that accelerator into a 32-bit RISC processor pipeline, in a closely-coupled configuration. 相似文献
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Wang J Ma T Zhang Z Zhang X Jiang Y Zhang G Zhao G Zhao H Zhang P 《Ultrasonics sonochemistry》2007,14(2):246-252
The transition crystal TiO(2) sonocatalyst was prepared utilizing the method of ultrasonic irradiation in hydrogen peroxide solution. The sonocatalytic activity of the transition crystal TiO(2) powder was validated through the degradation of methyl orange in aqueous solution by ultrasonic irradiation. The results show that the sonocatalytic activity of the transition crystal TiO(2) powder is obviously higher than that of pure rutile and anatase TiO(2) powders as well as mixed rutile and anatase TiO(2) powders according to the proportion of corresponding transition crystal TiO(2) catalyst. The degradation ratio of methyl orange in the presence of the transition crystal TiO(2) catalyst surpasses 75% within 80 min ultrasonic irradiation, while the degradation ratios are 55.93%, 51.68% and 40.88%, respectively, for rutile, mixed and anatase TiO(2) powders. 相似文献
127.
Graphene field-effect transistors (GFET) have emerged as powerful detection platforms enabled by the advent of chemical vapor deposition (CVD) production of the unique atomically thin 2D material on a large scale. DNA aptamers, short target-specific oligonucleotides, are excellent sensor moieties for GFETs due to their strong affinity to graphene, relatively short chain-length, selectivity, and a high degree of analyte variability. However, the interaction between DNA and graphene is not fully understood, leading to questions about the structure of surface-bound DNA, including the morphology of DNA nanostructures and the nature of the electronic response seen from analyte binding. This review critically evaluates recent insights into the nature of the DNA graphene interaction and its affect on sensor viability for DNA, small molecules, and proteins with respect to previously established sensing methods. We first discuss the sorption of DNA to graphene to introduce the interactions and forces acting in DNA based GFET devices and how these forces can potentially affect the performance of increasingly popular DNA aptamers and even future DNA nanostructures as sensor substrates. Next, we discuss the novel use of GFETs to detect DNA and the underlying electronic phenomena that are typically used as benchmarks for characterizing the analyte response of these devices. Finally, we address the use of DNA aptamers to increase the selectivity of GFET sensors for small molecules and proteins and compare them with other, state of the art, detection methods. 相似文献
128.
The most popular in vitro nucleic acid amplification techniques like polymerase chain reaction (PCR) including real-time PCR are costly and require thermocycling, rendering them unsuitable for uses at point-of-care. Highly efficient in vitro nucleic acid amplification techniques using simple, portable and low-cost instruments are crucial in disease diagnosis, mutation detection and biodefense. Toward this goal, isothermal amplification techniques that represent a group of attractive in vitro nucleic acid amplification techniques for bioanalysis have been developed. Unlike PCR where polymerases are easily deactivated by thermally labile constituents in a sample, some of the isothermal nucleic acid amplification techniques, such as helicase-dependent amplification and nucleic acid sequence-based amplification, enable the detection of bioanalytes with much simplified protocols and with minimal sample preparations since the entire amplification processes are performed isothermally. This review focuses on the isothermal nucleic acid amplification techniques and their applications in bioanalytical chemistry. Starting off from their amplification mechanisms and significant properties, the adoption of isothermal amplification techniques in bioanalytical chemistry and their future perspectives are discussed. Representative examples illustrating the performance and advantages of each isothermal amplification technique are discussed along with some discussion on the advantages and disadvantages of each technique. 相似文献
129.
A general overview of the development of the uses of light-emitting diodes in analytical instrumentation is given. Fundamental aspects of light-emitting diodes, as far as relevant for this usage, are covered in the first part. The measurement of light intensity is also discussed, as this is an essential part of any device based on light-emitting diodes as well. In the second part, applications are discussed, which cover liquid and gas-phase absorbance measurements, flow-through detectors for chromatography and capillary electrophoresis, sensors, as well as some less often reported methods such as photoacoustic spectroscopy. 相似文献
130.
Analysis of the odour complexity in food and beverage products demands high resolution approaches for distinguishing individual aroma-impact compound(s), and for assessing their contribution to the global aroma of a sample. This paper aims to review current applications incorporating different advanced separation methodologies, and their roles in achieving high resolution aroma analysis. This includes prior low resolution gas chromatography–olfactometry (GC–O) with fractionation procedures using chemical manipulation, adsorption chromatography and ion exchange separation. Innovative multidimensional gas chromatography (MDGC) arrangements that are appropriately designed with olfactometry are of specific focus here. The revelation of resolved components using these integrated approaches provides significantly improved knowledge of aroma composition in samples. 相似文献