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141.
In this study, a general comprehensive model is proposed for strategic closed-loop supply chain network design under interval data uncertainty. The proposed model considers various assumptions such as multiple periods, multiple products, and multiple supply chain echelons as well as uncertain demand and purchasing cost. In addition, bill of materials for each product is considered via a new approach in management of forward and reverse flows of products for producing new products and reusing or disassembling returned products. Uncertainty of parameters in the proposed model is handled via an interval robust optimisation technique. The model assumptions are well matched with decision making environments of food and high-tech electronics manufacturing industries. The factors that make these two industries similar are time-dependent properties of products such as prices and warehousing lifetime period. The computational results of solving the proposed model via LINGO 8 demonstrate efficiency of the proposed model in dealing with uncertainty in an agile manufacturing context. 相似文献
142.
F. Heydari A. Sheikholeslami K. G. Firouzjah S. Lesan 《Frontiers of Electrical and Electronic Engineering in China》2010,5(1):91-99
This paper is concerned with two popular and powerful methods in electrical drive applications: field-oriented control (FOC)
and space vector modulation (SVM). The proposed FOC-SVM method is incorporated with a predictive current control (PCC)-based
technique. The suggested method estimates the desirable electrical torque to track mechanical torque at a fixed speed operation
of permanent magnet synchronous motor (PMSM). The estimated torque is used to calculate the reference current based on FOC.
In order to improve the performance of the traditional SVM, a PCC method is established as a switching pattern modifier. Therefore,
PCC-based SVM is employed to further minimize the torque ripples and transient response. The performance of the controller
is evaluated in terms of torque and current ripple and transient response to step variations of the torque command. The proposed
method has been verified with MATLAB-Simulink model. Simulation results confirm the ability of this technique in minimizing
the torque and speed ripples and fixing switching frequency, simultaneously. However, it is sensitive to parameter changes. 相似文献
143.
Babak Mirtamizdoust Behrouz Shaabani Aliakbar Khandar Hadi Pourradi Yunes Abbasityula Hamid Goudarziafshar Davide Viterbo Gianluca Croce Pejman Hojati-Talemi 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(6):1293-1299
Preparation of plate-shaped nanostructures of a new 1D polymeric lead(II) complex containing the Pb2-(μ-I)2 motif, [Pb(neo)I2] n ,(1) where neo is the abbreviation of neocuproine, using a sonochemical method is described. The new coordination polymer is characterized by scanning electron microscopy, X-ray diffraction (XRD), elemental analysis and infrared spectroscopy. The single crystalline material is obtained using a heat gradient applied to a solution of the reagents. Single-crystal XRD analysis indicates that a coordination number of six for PbII ions, (i.e., PbN2I4) with an asymmetrical coordination sphere and “stereo-chemically active” electron lone pairs. They also show that the chains interact with each other through π–π stacking interactions creating a 3D framework. PbO nanoparticles are obtained by thermolysis of 1 at 180?°C with oleic acid as a surfactant. Scanning electron microscopy confirms formation of PbO particles with a size of ~25?nm. 相似文献
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Silicon - The electromagnetic stirrer method was developed to overcome the problems caused by the presence of a mechanical stirrer in the slurry; this method is nowadays considered to be the most... 相似文献
146.
Novin Shohreh Nouri Zarrabi Ferdows B. Bazgir Maryam Heydari Samaneh Ebrahimi Sepideh 《SILICON》2019,11(1):293-300
Silicon - In this paper, we present a split ring resonator (SRR) for a nano-aperture antenna for biomedical and spectroscopy applications. We have shown that while the graphene coat layer is... 相似文献
147.
The aim was the fabrication of glycodendrimer encapsulation agents with high proportions of cyclodextrins (CDs) to maintain the biocompatibility properties, as well as to notably improve their ability to load various suitably sized drugs. The novel glycodendrimers contained β‐CD in both core and branches, namely β‐cyclodextrin‐based dendrimer (CD‐dendrimer) prepared through a straightforward procedure using SN2 displacement to attach multivalent β‐CDs together. The desired CD‐dendrimer was synthesized in three steps: (i) reaction of β‐CD with p‐toluenesulfonyl chloride and/or iodine to afford C‐6 mono‐ and/or per‐β‐CD derivative; (ii) reaction of the β‐CD precursors with ethylenediamine to give C‐6 mono‐ and/or per‐amino‐β‐CD derivative; and (iii) SN2 displacement of β‐CD electrophilic derivative with β‐CD nucleophilic derivative in dimethylsulfoxide to provide the CD‐dendrimer. Then, the encapsulation behaviour of the CD‐dendrimer was examined using naproxen and naltrexone as the guest molecules. The structure of the designed CD‐dendrimer allowed two types of possible sites for encapsulation of the guest: in cavities of the dendritic structure and in hydrophobic cavities of CDs. © 2013 Society of Chemical Industry 相似文献
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Neus Gasulla Yusli Yaakob Jimmy Leblanc Aliakbar Akbarzadeh Jose Luis Cortina 《Solar Energy》2011,85(11):2894-2902
Brine transparency is an important part of the maintenance of a salinity-gradient solar pond as it affects the amount of solar radiation reaching the storage zone and hence has an influence on the thermal performance. There is a wide range of factors that can hinder the transmission of light in a solar pond. Algal and microbial growths are the most common problems encountered in working solar ponds and control of their densities is essential to maintain transparency. Two different chemical treatment methods for algae growth prevention are described in this paper: chlorine and a novel chemical product – copper ethylamine complex. The latter method has never been implemented previously in a working pond. This paper discusses the theory of the algae control methods used and presents the experimental results of the chemical treatments. The results showed that Cupricide is more effective than chlorine and is therefore the recommended chemical for algae control in solar ponds; it improves the water transparency especially in the upper convective zone and lower convective zone with all measurement values less than 1 NTU. Chlorine was found to be more corrosive than Cupricide due to the acidic effect it has on the pH. The preliminary cost analysis showed that granular chlorine is the cheapest chemical. A more detailed financial analysis is nevertheless required to refine these costs. 相似文献