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排序方式: 共有310条查询结果,搜索用时 15 毫秒
121.
Babylon is a collection of tools and services that provide a 100% Java‐compatible environment for developing, running and managing parallel, distributed and mobile Java applications. It incorporates features such as object migration, asynchronous method invocation, and remote class loading, while providing an easy‐to‐use interface. Additionally, Babylon enables Java applications to seamlessly create and interact with remote objects, while protecting those objects from other applications by implementing access restrictions and separate namespaces. The implementation of Babylon centers around dynamic proxies, a feature first available in Java 1.3, that allow proxy objects to be created at runtime. Dynamic proxies play a key role in achieving the goals of Babylon. The potential cluster computing benefits of the system are demonstrated with experimental results, which show that sequential Java applications can achieve significant performance benefits from using Babylon to parallelize their work across a cluster of workstations. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
122.
J. Quintelier P. Samyn L. De Doncker J. Vermeulen T. Tuzolana L. Cardon K. Ragaert P. De Baets J. Degrieck 《Polymer Composites》2009,30(7):932-940
Based on the well-known pin-on-disc test rig, a new test setup has been developed for online measuring of the wear and friction behavior of polymer matrix composites. Contrasting with a traditional friction and wear test rig, a steel pin and composite disc are presently used to study the influence of wear debris and fiber orientation. This test setup has a main influence on the results. The polymer materials, a thermoset polyester, and a thermoplastic polyphenylene sulfide were reinforced with glass and carbon fibers, respectively. The results show two different promising aspects of “new” materials for wear and friction applications and more specific to different machine components, namely self-lubricating and self-protecting ability. The self-lubricating ability exists from creating a polymer film on the surface which reduces the coefficient of friction, and the self-protecting behavior is because of the creation of a protecting carbon film on the surface. The self-lubricating ability depends on the test parameters, while the self-protecting ability was due to the material and the structure. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers 相似文献
123.
We present a novel optical-optical semiconductor switching technique for application to infrared laser beam modulation and ultrashort infrared laser pulse switching. This method relies on the ultrafast optical excitation, with femtosecond above-bandgap laser radiation, of an air-filled metal-clad semiconductor waveguide. Guided electromagnetic wave analysis combined with time-varying dielectric properties of the semiconductor layer are used to investigate the ultrafast switching speed of the structure. The device is capable of modulation at various infrared wavelengths. In particular, we investigate intensity modulation of the quasi-TE10 mode for 10.6-μm laser radiation. At an electron-hole photoinjection density of ~1.8×1018 cm-3, an extinction ratio of 83 dB is demonstrated. This ratio is significantly higher than that exhibited by current optical-optical semiconductor switches. Potential applications to all-optical Mach-Zehnder metal-clad semiconductor modulators and self-limiting switches are also discussed 相似文献
124.
Bert Vanhoutte Koen Dewettinck Imogen Foubert Brecht Vanlerberghe Andr� Huyghebaert 《European Journal of Lipid Science and Technology》2002,104(8):490-495
Different amounts of phospholipids (0.00‐0.07%) and water (0.00‐0.70%) were added to milk fat. The mixtures were crystallised under isothermal conditions and the crystallisation was monitored by differential scanning calorimetry and pulsed nuclear magnetic resonance. The crystallisation behaviour was described with the Avrami and Gompertz model which was fitted by non‐linear regression. Variance analysis revealed significant effects, whereas especially the induction time was influenced: higher concentrations of water seemed to decrease the induction time, while higher amount of phospholipids delayed the onset of crystallisation. No interaction effects between phospholipids and water were observed. An attempt to explain the effect of phospholipids on the induction time, based on the molecular interactions between phospholipids and triglycerides is proposed. This principle can be applied for sn‐1, 2 diglycerides as well. 相似文献
125.
Ernesto A Brovelli Jeffrey K Brecht Wayne B Sherman Charles A Sims Jay M Harrison 《Journal of the science of food and agriculture》1999,79(5):707-712
A study was conducted to determine differences in sensory and compositional characteristics of melting‐flesh (MF) and non‐melting flesh (NMF) fresh market peach genotypes. Sensory results showed that the NMF fruit (‘Oro A’ and FL 86‐28C) were ‘harder’, less ‘juicy’ and more ‘rubbery’ than their MF (FL 90‐20 and ‘TropicBeauty’) counterparts. A principal component analysis of the sensory data showed a clear distinction between the textural aspects of MF and NMF fruit, but not between their flavour aspects. Likewise, chemical analysis showed that while differences in pH, titratable acidity, and soluble solids were detected among the four genotypes, no consistent grouping could be made based on the MF/NMF nature of the fruit. © 1999 Society of Chemical Industry 相似文献
126.
Anabela S. Ramalho Mieke Boon Marijke Proesmans Franois Vermeulen Marianne S. Carlon Kris De Boeck 《International journal of molecular sciences》2022,23(3)
Cystic fibrosis, a multi-organ genetic disease, is characterized by abnormal function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, a chloride channel at the apical membrane of several epithelia. In recent years, therapeutic strategies have been developed to correct the CFTR defect. To evaluate CFTR function at baseline for diagnosis, or the efficacy of CFTR-restoring therapy, reliable tests are needed to measure CFTR function, in vitro, ex vivo and in vivo. In vitro techniques either directly or indirectly measure ion fluxes; direct measurement of ion fluxes and quenching of fluorescence in cell-based assays, change in transmembrane voltage or current in patch clamp or Ussing chamber, swelling of CFTR-containing organoids by secondary water influx upon CFTR activation. Several cell or tissue types can be used. Ex vivo and in vivo assays similarly evaluate current (intestinal current measurement) and membrane potential differences (nasal potential difference), on tissues from individual patients. In the sweat test, the most frequently used in vivo evaluation of CFTR function, chloride concentration or stimulated sweat rate can be directly measured. Here, we will describe the currently available bio-assays for quantitative evaluation of CFTR function, their indications, advantages and disadvantages, and correlation with clinical outcome measures. 相似文献
127.
128.
This paper describes an architecture for controlling multiple IEEE 1149.1 compliant TAP controllers on a single digital system chip. The key feature of this architecture is the compatibility with the IEEE 1149.1 standard, and existing debugger software. Results are presented, obtained from an experiment, in which the proposed architecture is mapped on an FPGA to control multiple existing designs with TAP controllers. 相似文献
129.
AT Natarajan SJ Santos F Darroudi V Hadjidikova S Vermeulen S Chatterjee M Berg M Grigorova ET Sakamoto-Hojo F Granath AT Ramalho MP Curado 《Canadian Metallurgical Quarterly》1998,400(1-2):299-312
The radiation accident in focus here occurred in a section of Goiania (Brazil) where more than a hundred individuals were contaminated with 137Cesium on September 1987. In order to estimate the absorbed radiation doses, initial frequencies of dicentrics and rings were determined in 129 victims [A.T. Ramalho, PhD Thesis, Subsidios a tecnica de dosimetria citogenetica gerados a partir da analise de resultados obtidos com o acidente radiologico de Goiania, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, 1992]. We have followed some of these victims cytogenetically over the years seeking for parameters that could be used as basis for retrospective radiation dosimetry. Our data on translocation frequencies obtained by fluorescence in situ hybridization (FISH) could be directly compared to the baseline frequencies of dicentrics available for those same victims. Our results provided valuable information on how precise these estimates are. The frequencies of translocations observed years after the radiation exposure were two to three times lower than the initial dicentrics frequencies, the differences being larger at higher doses (>1 Gy). The accuracy of such dose estimates might be increased by scoring sufficient amount of cells. However, factors such as the persistence of translocation carrying lymphocytes, translocation levels not proportional to chromosome size, and inter-individual variation reduce the precision of these estimates. 相似文献
130.
Vermeulen B. Wellen J. Geilhardt F. Weis E. Mas C. Dhoedt B. Demeester P. 《Lightwave Technology, Journal of》2004,22(11):2592-2605
The ever-increasing use of broad-band Internet and complex multimedia applications is pushing fiber closer and closer to the homes. Within the European project IST HARMONICS (Hybrid Access Reconfigurable Multi-wavelength Optical Networks for IP-based Communication Services), an optical access feeder network and resource management framework were developed that tackle this demand for bandwidth and the desire to stimulate the convergence of last-mile access technologies. To cope with the lack of bandwidth in the access and last-mile networks and the different needs of applications and users, the developed management system provides end-to-end quality of service (QoS) while integrating multiple technologies. In this paper, a detailed overview of the end-to-end QoS management framework and novel time slot/wavelength MAC protocol for the optical feeder network is given. End-to-end QoS is based on Differentiated services (DiffServ) at layer 3, various QoS supporting technologies at layer 2, and QoS mappings between both layers. The paper will also focus on the field trial results of the HARMONICS project and give some guidelines for possible problems and solutions in this area. 相似文献