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1.
The main purpose of this study was to evaluate the performance of the electrochemical oxidation process as a post-treatment for the effluents of a bench-scale UASB reactor treating simulated wastewater from an unbleached pulp plant. The oxidation process was performed using a single compartment cell with two plates as electrodes. The anode was made of Ti/Ru0.3Ti0.7O2 and the cathode of stainless steel. The following variables were evaluated: current density (75, 150 and 225 mA cm(-2)) and recirculation flow rate in the electrochemical cell (0.22, 0.45 and 0.90 L h(-1)). The increase in current density from 75 to 225 mA cm(-2) did not increased the color removal efficiency for the tested flow rates, 0.22, 0.45 and 0.90 L h(-1), however the energy consumption increased significantly. The results indicated the technical feasibility of the electrochemical treatment as post-treatment for UASB reactors treating wastewaters from pulp and paper plants. 相似文献
2.
A Monte Carlo simulation method for calculating the probability of soil liquefaction of a finite area in which the ground motion is propagated upward from the bedrock through the soil layers is presented. The vertical propagation of the ground motion through the soil layers is analyzed using random vibration analysis. To account for the variability of soil properties with depth, the soil deposit is divided into layers. Within each layer the horizontal statistical correlation of the undrained cyclic shearing strength against liquefaction is taken into consideration by describing it as a two-dimensional homogeneous random field. The method computes the probability of liquefaction spreading over a specified area under a given earthquake loading considering the effects of spatial correlation of soil properties. 相似文献
3.
Mario J. Pires Joaquim M. S. Cabral 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,61(3):219-224
Recombinant cytochrome b5 was extracted into the reversed micelle phase of an anionic surfactant (AOT) in octane and back-extracted to a final aqueous phase. The extraction of the protein was controlled by an electrostatic mechanism, since it was dependent on the global charge of the protein. This was directly demonstrated by experiments with native and mutant cytochromes obtained by site directed mutagenesis. The back-extraction of cytochrome b5 to a fresh aqueous phase was decreased by factors that reduced the size of the water pool of the organic phase, such as high salt concentrations (1–2 mol dm?3 NaCl) and low temperatures (4°C), probably because of an increase in a favourable interaction of this protein with the surfactant at closer distances. 相似文献
4.
A comprehensive model to evaluate the seismic reliability of electric power transmission systems is presented. The model provides information on the probability of structural failure of critical equipment at the major substations, from which the corresponding probabilities of power disruption to a given service area are determined. With the proposed methodology earthquake ground motions are defined as stochastic processes, and seismic capacities of electrical equipment are determined on the basis of available test data and simple modeling, from which fragility functions of critical equipment and specific substations are developed. Probabilities of power disruption resulting from network disconnectivity and abnormal power flow are assessed through Monte Carlo simulation. As a case study, the proposed model is applied to the electric power network in San Francisco and vicinity under the 1989 Loma Prieta earthquake, and the probabilities of power interruption are contrasted with the actual power failures observed during that earthquake. 相似文献
5.
Blends of isotactic polypropylene (PP), ethylene‐propylene rubber copolymer (EPR), and ethylene‐propylene crystalline copolymer (EPC) can be produced through in situ polymerization processes directly in the reactor and blends with different structure and composition can be obtained. In this work we studied the structure of five reactor‐made blends of PP, EPR, and EPC produced by a Ziegler‐Natta catalyst system. The composition of EPR was related to the ratio between ethylene and propylene used in the copolymerization step. The ethylene content in the EPR was in the range of 50–70 mol %. The crystallization behavior of PP and EPC in the blends was influenced by the presence of the rubber, and some specific interactions between the components could be established. By preparative temperature rising elution fractionation (P‐TREF) analysis, the isolation and characterization of crystalline EPC fractions were made. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2155–2162, 2004 相似文献
6.
Frederico Lopes Flavia C. Delicato Thais Batista Everton Cavalcante Thiago Pereira Paulo F. Pires 《International Journal of Parallel, Emergent and Distributed Systems》2014,29(2):178-212
In this paper, we present OpenCOPI (Open COntext Platform Integration), a Service-Oriented Architecture-based middleware platform that supports the integration of services provided by distinct sources, ranging from services offered by simple systems to more complex services provided by context-provision middleware. OpenCOPI offers selection and composition mechanisms to, respectively, select and compose services provided by different sources, considering applications of both Quality of Service and Quality of Context requirements. It also offers an adaptation mechanism that enables to adapt the application execution due to service failures, service quality fluctuation and user mobility. OpenCOPI allows the definition of applications in a higher abstraction level by the specification of a semantic workflow that contains abstract activities. This paper illustrates the use of OpenCOPI in an application from the Gas & Oil Industry and it also shows the evaluation of the main mechanisms of OpenCOPI: the service selection, composition, adaptation and workflow execution. 相似文献
7.
Belletier Clément Charkhabi Morteza Pires de Andrade Silva Gustavo Ametepe Kevin Lutz Mathieu Izaute Marie 《Cognition, Technology & Work》2021,23(1):103-116
Cognition, Technology & Work - Rapid technological innovations are constantly influencing the complexification and automatization of the work lines pushing human operators to use diverse... 相似文献
8.
Luciana Gampert Miranda Carolina Pereira Peglow Victória Cardoso Deorristt Geórgia Campos Sales Neto Ariela Milbrath Cardoso Suzana Frighetto Ferrarini Marçal José Rodrigues Pires 《应用聚合物科学杂志》2021,138(7):49842
The use of polymeric films incorporated with zeolite-TiO2 composites associated with UV radiation can be an alternative in the removal of volatile organic compounds (VOCs) through the adsorption and photodegradation processes. This study produced poly(lactic acid) (PLA) films incorporated with 13× zeolite, TiO2, and 13×-TiO2 zeolite composite to remove n-butanol and evaluate the by-products generated in the process. The results showed that 13× zeolite and TiO2 added individually or as a composite to PLA, gave the polymer matrix a significant increase in the removal capacity of n-butanol. The best performance was presented by the zeolite-TiO2, composite, confirming a synergistic effect. However, the formation of CO and CO2 exceeded the expected values, with the verification that the polymeric matrix underwent photodegradation action by TiO2. The polymeric film only containing zeolite is the most suitable for the removal of VOCs, as it did not present degradation of the PLA, generating a lower concentration of by-products. 相似文献
9.
Luci Pirmez Jaime C. Carvalho Flávia C. Delicato Fábio Protti Luiz F.R.C. Carmo Paulo F. Pires Marcos Pirmez 《Computer Networks》2010,54(13):2117-2136
This work presents SUTIL, a mechanism for network selection in the context of next generation networks (NGN). SUTIL selection mechanism prioritizes networks with higher relevance to the application and lower energy consumption and it enables full and seamless connectivity to mobile user devices and applications. Consequently, SUTIL contributes to realize the vision of ubiquitous computing, in which services, devices, and sensor-enriched environments interact anytime, anywhere to accomplish human designed tasks. The provided solution is based on utility function and integer linear programming and it aims at: (i) maximizing the user satisfaction while meeting application QoS and (ii) minimizing the energy consumption of devices when connecting to a target network. The solution is global since it considers for a given base station all devices that are simultaneously candidate for handoff. Simulation results showed the benefits of SUTIL usage in NGN environments. 相似文献
10.
Dimas Cassimiro Nascimento Carlos Eduardo Pires Demetrio Gomes Mestre 《Applied Intelligence》2016,45(2):530-548
Deduplication is the task of identifying the entities in a data set which refer to the same real world object. Over the last decades, this problem has been largely investigated and many techniques have been proposed to improve the efficiency and effectiveness of the deduplication algorithms. As data sets become larger, such algorithms may generate critical bottlenecks regarding memory usage and execution time. In this context, cloud computing environments have been used for scaling out data quality algorithms. In this paper, we investigate the efficacy of different machine learning techniques for scaling out virtual clusters for the execution of deduplication algorithms under predefined time restrictions. We also propose specific heuristics (Best Performing Allocation, Probabilistic Best Performing Allocation, Tunable Allocation, Adaptive Allocation and Sliced Training Data) which, together with the machine learning techniques, are able to tune the virtual cluster estimations as demands fluctuate over time. The experiments we have carried out using multiple scale data sets have provided many insights regarding the adequacy of the considered machine learning algorithms and proposed heuristics for tackling cloud computing provisioning. 相似文献