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131.
Yaman Ay?e; Mesman Judi; van IJzendoorn Marinus H.; Bakermans-Kranenburg Marian J. 《Canadian Metallurgical Quarterly》2010,24(2):208
We investigated the influence of parenting practices in the prediction of child physical aggression in 94 second-generation Turkish immigrant families with 2-year-old toddlers, and the moderating role of child temperament. In a longitudinal study we tested both a dual-risk model and a differential susceptibility model. Observational data were obtained for mothers’ positive parenting and authoritarian discipline, and maternal reports for child temperament and physical aggression. All measures were repeated 1 year later. Child temperament at age 2 years was a significant predictor of child aggression 1 year later. We found no main effects of positive parenting or of authoritarian discipline for the prediction of child aggression. However, we found support for the dual-risk hypothesis: Toddlers with difficult temperaments were more adversely affected by a lack of positive parenting than other children, but they did not benefit more from high levels of positive parenting than toddlers with more easy temperaments. We found no interaction effects with child temperament for authoritarian discipline. These findings provide support for the generalizability of the dual-risk model of parenting and temperament to non-Western immigrant families with young children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
132.
Melek Erol Ayşe Özyuğuran Özlem Özarpat Sadriye Küçükbayrak 《Journal of the European Ceramic Society》2012,32(11):2747-2755
In this study, it was aimed to fabricate and characterize three-dimensional composite scaffolds derived from Sr-doped bioactive glass for bone tissue engineering applications. The scaffolds were fabricated by using polymer foam replication technique and coated with gelatin to be able to improve the properties of them. The porous scaffolds were successfully synthesized using optimized process parameters. Both coated and uncoated scaffolds favored precipitation of calcium phosphate layer when they were soaked in simulated body fluid (SBF). Gelatin coating improved the mechanical properties of the scaffold and also it did not change the bioactive behavior of the scaffold. It was observed that there was a good pore interconnectivity maintained in the scaffold microstructure. Results indicated that scaffolds can deliver controlled doses of strontium toward the SBF medium. That is the determinant for bone tissue regeneration, as far as strontium is known to positively act on bone remodeling. 相似文献
133.
The conversion of monomer to its polymer may not be complete and residual monomer is left over in the polymeric matrix; this, in turn, affects the properties of the polymeric matrix. In this study, we wanted to compare residual monomer content of the unreinforced conventional heat-polymerized and microwave-polymerized acrylic resins with those of fiber-reinforced ones. High performance liquid chromatography was used for the determination of the residual monomer content. Statistical analysis of the results was carried out with a confidence level of 95%. It was observed that conventional heat-polymerized denture base resin resulted in a relatively higher residual monomer content than the microwaved one. Conventional heat-polymerized denture base resin with fiber reinforcement caused an increase in the residual monomer content. Furthermore, the change in the residual monomer content of microwave-polymerized denture base resin with fiber reinforcement was not statistically significant compared with no fiber reinforcement. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
134.
Murat Akarsu Esin Burunkaya Ayşe Tunalı Neslihan Tamsü Selli Ertuğrul Arpaç 《Ceramics International》2014
The aim of this study was to improve stain resistance and cleanability of polished porcelain tiles by sealing the micro-pores on the tile surface with hybrid sol–gel solution. For this purpose, solutions of a hybrid system based on sol–gel technology were prepared. The obtained solution were applied to polished unglazed tiles and subsequently spread with soft tissue thereon. To achieve complete sealing, both organic and inorganic particles of different sizes were mixed with obtained sol–gel hybrid systems. Coated surfaces were investigated by means of a scanning electron microscope. The stain resistance and the cleanability of the tile surface were tested according to ISO-10545-2014 standard. It has been shown that prepared sealing material permanently prevents formation of stains such as olive oil, green staining paste, iodine solution on the surface of polished porcelain tiles. The remains of stains on the surface can easily be removed from it with a cleaning agent. 相似文献
135.
A total of 28 different plants from different regions of Çanakkale, Turkey, were investigated for their antioxidant capacity and total phenol contents to find new potential sources of natural antioxidants. The antioxidant capacity of methanolic extracts prepared from various parts of plants was evaluated by both trolox equivalent antioxidant capacity (TEAC) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assays, while the total phenolics were determined using the Folin‐Ciocalteu method. The TEAC values of plant extracts ranged in a large scale from 1472.36 to 17.61 μmol of trolox equivalents per g dry weight (dw), and EC50 values (concentration at which 50% radical scavenging occurred) varied from 0.174 to 42.475 mg dw of plant, while the total phenol content of plant extracts ranged between 117.20 and 1.27 mg of gallic acid equivalents per g dw. There was a positive linear correlation between the TEAC and total phenols of plant materials (r = 0.916). The extracts of Hypericum perforatum, Arbutus andrachne and Paliurus spina‐christii showed higher antioxidant activities (both TEAC and DPPH assays). However, there was no clear relationship between TEAC and EC50 values (r = 0.477) of plant extracts. 相似文献
136.
Thermogravimetric studies of poly(acrylic acid) (PAA) and its chromium–polyacrylate complexes prepared from Cr(III) solutions aged for different times were undertaken. Six kinetic methods were used to investigate the thermal decomposition behavior of these materials. The applied methods were the Coats–Redfern, Horowitz–Metzger, MacCallum–Tanner, van Krevelen, Madhusudanan–Krishnan–Ninan, and Criado methods. The activation energy values obtained with the Coats–Redfern, Horowitz–Metzger, and MacCallum–Tanner methods were in good agreement with one another, and those obtained with the van Krevelen and Madhusudanan–Krishnan–Ninan methods were found to be 10–20 kJ/mol larger. The apparent activation energies increased for the complexes prepared from Cr(III) solutions aged for longer times. An analysis of the experimental results suggested that the actual decomposition mechanisms of PAA and the metal–polymer complexes were a Dn deceleration type. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
137.
José de Jesús Nuño Ayón Jorge Luis García Sánchez Eduardo Salvador Bañuelos Cabral Julián Sotelo Castañón María José Rodríguez Roblero 《电力部件与系统》2020,48(6-7):615-627
Abstract Wide-area power system monitoring based on phasor measurement units allows collecting a set of physical variables for evaluating the system security and stability, as well as for detecting power system disturbances. However, trends, noise and non-Gaussian distribution in measurements are important challenges for carrying out the detection, localization and visualization of power system disturbances. In this paper, a methodology that combines independent component analysis with statistical indices for detecting and visualizing anomalous dynamic events from wide-area measurements is proposed. From the statistical indices, two charts are also proposed to provide a better understanding of the system disturbances. Finally, a set of simulated data obtained from a transient stability model of the New England/New York test system is used to demonstrate the effectiveness of the proposed technique. 相似文献
138.
Ay N 《Neural computation》2002,14(12):2959-2980
The hypothesis of invariant maximization of interaction (IMI) is formulated within the setting of random fields. According to this hypothesis, learning processes maximize the stochastic interaction of the neurons subject to constraints. We consider the extrinsic constraint in terms of a fixed input distribution on the periphery of the network. Our main intrinsic constraint is given by a directed acyclic network structure. First mathematical results about the strong relation of the local information flow and the global interaction are stated in order to investigate the possibility of controlling IMI optimization in a completely local way. Furthermore, we discuss some relations of this approach to the optimization according to Linsker's Infomax principle. 相似文献
139.
140.
With a large number of techniques particularly used in the treatment of sewage and water, knowledge about flow behavior of permeable agglomerate structures moved in the fluid phase plays an important role in the design of processes and plants. In mechanical separating techniques, this flow behavior has an influence on sedimentation of aggregates in the gravitational field. This knowledge is also necessary for the optimization and specific development of carrier systems for biological process levels with immobilized microorganisms. This paper focuses on the development and verification of a suitable investigation methodology to quantify relevant influencing factors with a view to both the rate of sedimentation of agglomerate structures and flow resistance. 相似文献