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21.
Many existing and emerging Scientific high-end applications (E-science) require end-to-end circuits interconnecting Grid resources for large data transfers. A few advanced networks, mainly National Research and Education Networks (NRENs), such as Surfnet, National Lambda Rail and Internet 2, now provide mechanisms for end-users to reserve and provision lightpaths via middleware referred to as Network Resource Mangers (NRMs). Although, some progress has been made in automated intra-domain lightpath services, inter-domain lightpath provisioning still requires manual intervention and presents several key challenges such as scalability of topology information exchanged, consistency and scalability of information model, security of access to the resources, hybrid networking and multi-layer lightpaths, and accounting and billing. In this paper, we describe a new architectural framework called Global Lambda Integrated Facility (GLIF) Interdomain Resource Reservation Architecture (GIRRA) with the goal to provide an integrated response to these challenges. We propose a new approach to model GLIF network domains and GOLEs as virtual switches and to describe their behavior, functionality, policy capabilities, and topology aggregation. We define an inter-domain path computation model to determine paths that meet constraints and access policy restrictions. We propose a security framework for authentication and authorization of users and a model for accounting and billing that aims to provide easy and secure access to the resources. Key aspects of the GIRRA solution are that it focuses on the inter-dependence between different challenges of inter-domain path provision, and it is built around already existing solutions for intra-domain resource provisioning. 相似文献
22.
Rapid and direct estimation of active biomass on granular activated carbon through adenosine tri-phosphate (ATP) determination 总被引:1,自引:0,他引:1
Granular activated carbon (GAC) filtration is used during drinking water treatment for the removal of micropollutants such as taste and odour compounds, halogenated hydrocarbons, pesticides and pharmaceuticals. In addition, the active microbial biomass established on GAC is responsible for the removal of biodegradable dissolved organic carbon compounds present in water or formed during oxidation (e.g., ozonation and chlorination) processes. In order to conduct correct kinetic evaluations of DOC removal during drinking water treatment, and to assess the state and performance of full-scale GAC filter installations, an accurate and sensitive method for active biomass determination on GAC is required. We have developed a straight-forward method based on direct measurement of the total adenosine tri-phosphate (ATP) content of a GAC sample and other support media. In this method, we have combined flow-cytometric absolute cell counting and ATP analysis to derive case-specific ATP/cell conversion values. In this study, we present the detailed standardisation of the ATP method. An uncertainty assessment has shown that heterogeneous colonisation of the GAC particles makes the largest contribution to the combined standard uncertainty of the method. The method was applied for the investigation of biofilm formation during the start-up period of a GAC pilot-scale plant treating Lake Zurich water. A rapid increase in the biomass of up to 1.1 x 10(10)cells/g GAC dry weight (DW) within the first 33 days was observed, followed by a slight decrease to an average steady-state concentration of 7.9 x 10(9)cells/g GAC DW. It was shown that the method can be used to determine the biomass attached to the GAC for both stable and developing biofilms. 相似文献
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24.
Carlo Beatrice Chiara Guido Pierpaolo Napolitano Silvana Di Iorio Nicola Del Giacomo 《Fuel》2011,90(5):2039-2044
Results of a research project aimed at studying the capability to develop a method (economic and simple) for on-board biodiesel blending detection are described. The method is based on the direct measurement of the Indicated Mean Effective Pressure (IMEP).The study was carried out on a 2.0L four-cylinder “torque-controlled” Euro 5 diesel engine for passenger car (PC) application. This engine, equipped with instrumented glow plug for combustion closed-loop control, represents the state of the art of the diesel engine control technology.Two biodiesels were chosen for the experiments: a rapeseed methyl-ester (RME) and an aged RME, while the conventional diesel fuel was an European (EU) certification diesel fuel.Results indicate generally a good response in blending detection of the method. However, in order to attain an acceptable accuracy, a pre-calibration appears necessary. 相似文献
25.
Fernanda Peyronel Joseph Cooney Erzsebet Papp-Szabo Silvana Martini David Pink 《Journal of the American Oil Chemists' Society》2023,100(12):961-974
Three oleogelator molecules (Triacontane (TC), Stearic acid (SA), and Behenyl Lignocerate (BL)) were studied individually, in pairs, or all together to make an oleogel using triolein as the oil. WAXS, SAXS and USAXS were used to elucidate the solid structures from angstroms to a few micrometers. A two-dimensional mapping of atomic positions for each molecule was carried out to understand the crystalline multilayer structures formed. We assumed that the molecules were rigidly extended and that they underwent no significant (hindered) rotations so that the free energy is determined by the Lennard-Jones interactions of closely packed multilayers. TC molecules were predicted to form a tilt angle of , yielding a SAXS line at Å─1, in acceptable agreement with the measured . For SA crystals (predicted) yielding a SAXS line at compared to (observed). No mixed crystals were observed for any pair of molecules or when all three were used. USAXS data showed that SA forms large nanocrystals compared to TC and BL. All three combinations of molecular pairs showed basic scatterers smaller or similar to those of individual molecules. The theory presented here, together with the experimental results, showed why no mixed crystals are formed from two or all three molecules. Data from the USAXS region suggested that, when using all three molecules, a more compact fractal structure was obtained, compared with those if one or two of the molecules were used. 相似文献
26.
The objective of this work was to study the effect of sourdough obtained with selected exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) strains on the quality of bread and its shelf life. Two sourdough concentrations were used in order to ascertain the best bread composition. Fresh bread quality was studied by means of microbiological, physical, chemical and mechanical analysis, whereas physical, thermal and mechanical properties were investigated to study the product shelf life. The results showed that dough prepared with 30 g/100 g of sourdough had a negative impact on bread quality properties in the absence of EPS-producing LAB strains, whereas the opposite was observed in the presence of EPS-producing strains: bread samples at 30 g/100 g of sourdough showed higher volume, higher moisture content and better mechanical properties during storage than samples at 20 g/100 g of sourdough. Moreover, 30 g/100 g of sourdough showed a protective effect on bread staling, thus confirming the effect of sourdough concentration and the positive role of EPS on functional properties. 相似文献
27.
Intrusion Detection System for Wireless Sensor Networks Using Danger Theory Immune-Inspired Techniques 总被引:1,自引:0,他引:1
Helio Mendes Salmon Claudio M. de Farias Paula Loureiro Luci Pirmez Silvana Rossetto Paulo Henrique de A. Rodrigues Rodrigo Pirmez Flávia C. Delicato Luiz Fernando R. da Costa Carmo 《International Journal of Wireless Information Networks》2013,20(1):39-66
An IDS framework inspired in the Human Immune System to be applied in the wireless sensor network context is proposed. It uses an improved decentralized and customized version of the Dendritic Cell Algorithm, which allows nodes to monitor their neighborhood and collaborate to identify an intruder. The work was implemented and tested both in simulation and in real sensor platform scenarios, comparing them to each other and was also compared to a Negative Selection Theory implementation in order to demonstrate its efficiency in detecting a denial-of-sleep attack and in energy consumption. Results demonstrated the success of the proposal. 相似文献
28.
Silvana Sommadossi Horacio E. Troiani Armando Fernández Guillermet 《Journal of Materials Science》2007,42(23):9707-9712
In this work preliminary results are reported on the characterization of Pb-free joints produced by using a diffusion soldering
method at a process temperature of 700 °C during 20 min. The solder alloy is a metallic paste involving Ga and Al and Ni powder,
and the substrates are Cu and Ni. The dissolution and diffusion-reaction processes, which take place at the interfaces of
the interconnection zone, have been investigated by means of SEM and EPMA. A solid solution and intermetallic compounds (IMCs)
with high melting point form as layers almost free from defect, allowing service temperatures about 500 °C higher than the
process temperature. The phase stability sequence starting from the Ni to the Cu interface is the following: α′-Ni3Ga, γ-Cu9Ga4, β-Cu3Ga and (Cu) solid solution of the Ga–Cu system. The relative reaction front displacement of the layers and the implications
of the present findings for the applicability of the diffusion-soldering method are also discussed. 相似文献
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30.
Synthesis and Biological Evaluation of Papain‐Family Cathepsin L‐Like Cysteine Protease Inhibitors Containing a 1,4‐Benzodiazepine Scaffold as Antiprotozoal Agents 下载免费PDF全文
Dr. Roberta Ettari Dr. Andrea Pinto Dr. Lucia Tamborini Dr. Ilenia C. Angelo Prof. Silvana Grasso Prof. Maria Zappalà Dr. Natale Capodicasa Dr. Laura Yzeiraj Dr. Esther Gruber Dr. Makoah N. Aminake Dr. Gabriele Pradel Prof. Tanja Schirmeister Prof. Carlo De Micheli Prof. Paola Conti 《ChemMedChem》2014,9(8):1817-1825
Novel papain‐family cathepsin L‐like cysteine protease inhibitors endowed with antitrypanosomal and antimalarial activity were developed, through an optimization study of previously developed inhibitors. In the present work, we studied the structure–activity relationships of these derivatives, with the aim to develop new analogues with a simplified and more synthetically accessible structure and with improved antiparasitic activity. The structure of the model compounds was significantly simplified by modifying or even eliminating the side chain appended at the C3 atom of the benzodiazepine scaffold. In addition, a simple methylene spacer of appropriate length was inserted between the benzodiazepine ring and the 3‐bromoisoxazoline moiety. Several rhodesain and falcipain‐2 inhibitors displaying single‐digit micromolar or sub‐micromolar antiparasitic activity against one or both parasites were identified, with activities that were one order of magnitude more potent than the model compounds. 相似文献