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141.
Refined olive-pomace oil (ROPO) was utilized as a source for the production of a cocoa butter (CB)-like fat. Immobilized sn-1,3 specific lipase-catalyzed acidolysis of ROPO with palmitic (PA) and stearic (SA) acids was performed at various substrate mole ratios (ROPO:PA:SA) to produce major triacylglycerols (TAGs) of CB. Products obtained for various substrate mole ratios were compared to a commercial CB in terms of TAG content, melting profile, solid fat content (SFC) and microstructure. The fat produced at a substrate mole ratio of 1:2:6 was the most similar to CB. The product contained 11% POP, 21.8% POS, 15.7% SOS while commercial CB contained 18.9% POP, 33.1% POS and 24.7% SOS. The product had a melting peak of 29.9 °C while CB had one of 28.5 °C. Polarized light microscope (PLM) images showed that fat crystal network microstructures of this product and CB were very similar.  相似文献   
142.
Metabolic syndrome (MetSyn) is a major health problem affecting approximately 25% of the worldwide population. Since the gut microbiota is highly connected to the host metabolism, several recent studies have emerged to characterize the role of the microbiome in MetSyn development and progression. To this end, our study aimed to identify the microbiome patterns which distinguish MetSyn from type 2 diabetes mellitus (T2DM). We performed 16S rRNA amplicon sequencing on a cohort of 70 individuals among which 40 were MetSyn patients. The microbiome of MetSyn patients was characterised by reduced diversity, loss of butyrate producers (Subdoligranulum, Butyricicoccus, Faecalibacterium prausnitzii) and enrichment in the relative abundance of fungal populations. We also show a link between the gut microbiome and lipid metabolism in MetSyn. Specifically, low-density lipoproteins (LDL) and high-density lipoproteins (HDL) display a positive effect on gut microbial diversity. When interrogating the signature of gut microbiota in a subgroup of patients harbouring both MetSyn and T2DM conditions, we observed a significant increase in taxa such as Bacteroides, Clostridiales, and Erysipelotrichaceae. This preliminary study shows for the first time that T2DM brings unique signatures of gut microbiota in MetSyn patients. We also highlight the impact of metformin treatment on the gut microbiota. Metformin administration was linked to changes in Prevotellaceae, Rickenellaceae, and Clostridiales. Further research focusing on the microbiome-metabolome patterns is needed to clarify the exact association of various gut microbial communities with the progression of T2DM and the occurrence of various complications in MetSyn patients.  相似文献   
143.
In this paper, two new approaches are proposed for extracting composite priority rules for scheduling problems. The suggested approaches use simulation and gene expression programming and are able to evolve specific priority rules for all dynamic scheduling problems in accordance with their features. The methods are based on the idea that both the proper design of the function and terminal sets and the structure of the gene expression programming approach significantly affect the results. In the first proposed approach, modified and operational features of the scheduling environment are added to the terminal set, and a multigenic system is used, whereas in the second approach, priority rules are used as automatically defined functions, which are combined with the cellular system for gene expression programming. A comparison shows that the second approach generates better results than the first; however, all of the extracted rules yield better results than the rules from the literature, especially for the defined multi-objective function consisting of makespan, mean lateness and mean flow time. The presented methods and the generated priority rules are robust and can be applied to all real and large-scale dynamic scheduling problems.  相似文献   
144.
145.
The structure and mechanical properties of bio‐nanocomposite films made from poly(ethylene oxide) (PEO) that is physically cross‐linked with silicate nanoparticles, Laponite, are investigated. Direction‐dependent mechanical properties of the films are presented, and the effect of shear orientation during sample preparation on tensile strength and elongation is assessed. Repeated mechanical deformation results in highly extensible materials with preferred orientation and structuring at the nano‐ and micrometer scales. Additionally, in vitro biocompatibility data are reported, and NIH 3T3 fibroblasts are observed to readily adhere and proliferate on silicate cross‐linked PEO while maintaining high cell viability.  相似文献   
146.
147.
The evaluation of risky assets is one of the major research tasks in the finance theory. There are several Capital Asset Pricing Models (CAPM) in the literature; the most popular one of those is the Sharpe–Lintner–Black mean–variance CAPM. According to this model, the typical measure of systematic risk is the beta coefficient. The beta coefficient can be evaluated by means of least squares method (LSM), Robust Regression Techniques (RRT), or similar approaches. However, the statistical assumptions of LSM might be invalid in the existence of extreme observations in data set. In order to decrease influence on the beta coefficient of extreme observations, most analyst apply to RRT’s. However, either RRT’s remove the extreme observations from the data set, or decrease their influences on the beta coefficient. Whereas the omitted observations might be valuable for investors since they carry substantial information about the state of nature. In other words, there is a clash between statistical and financial theory. In this study, to overcome this incompatibility, and to take into account the extreme observations carried worthy information, a novel fuzzy regression approach is proposed. The proposed approach is based on both possibility concepts and central tendency in the estimation of beta coefficient. In application section of this paper, the beta coefficients of three assets traded in Istanbul Stock Exchange (ISE) are estimated by the proposed fuzzy approach and the traditional techniques, and then the results of analysis are compared, and discussed.  相似文献   
148.
Polymeric scaffolds with complex porous structures were fabricated with two different polymers by combining three fabrication methods in three steps, in which, nonwoven poly(ε-caprolactone) microfibers were obtained with electrospinning and immersed in solvent cast chitosan solution poured in Petri dish to fabricate hybrid polymers, and finally the combined structure was freeze-dried with two different predrying techniques to obtain macropores in the structure. The resulting hybrid polymeric mats were found to have both microfibers and macroporosity due to the electrospinning as well as freeze-drying processes, which resemble the natural extracellular matrix. The optimized scaffolds that predried in the incubator at 40°C for 5?h and then freeze-dried for 24?h exhibited contact angle value of 68.93?±?2.18° with 3.252?±?0.783?MPa Young’s modulus and 0.260?±?0.002?MPa yield strength as well as 1.35-fold cell yield in MRC5 fibroblast cell culture, compared to the commercial tissue culture polystyrene.  相似文献   
149.
A novel biofabrication modality, electrophoretic compaction with macromolecular alignment, is utilized to make collagen threads that mimic the native tendon's structure and mechanical properties. A device with kinematic electrodes is designed to fabricate collagen threads in continuous length. For the first time, a 3D‐biotextile is woven purely from collagen. Mechanical properties and load‐displacement behavior of the biotextile mimic those of the native tendon while presenting a porosity of 80%. The open pore network facilitates cell seeding across the continuum of the bioscaffold. Mesenchymal stem cells (MSCs) seeded in the woven scaffold undergo tenogenic differentiation in the absence of growth factors and synthesize a matrix that is positive for tenomodulin, COMP and type I collagen. Up‐regulation of tenomodulin, a tendon specific marker, is 11.6 ± 3.5 fold, COMP is up‐regulated 16.7 ± 5.5 fold, and Col I is up‐regulated 6.9 ± 2.7 fold greater on ELAC threads when compared to randomly oriented collagen gels. These results demonstrate that a bioscaffold woven using collagen threads with densely compacted and anisotropically aligned substrate texture stimulates tenogenesis topographically, rendering the electrochemically aligned collagen as a promising candidate for functional repair of tendons and ligaments.  相似文献   
150.
Cold spray is a developing technology that is increasingly finding applications for coating of similar and dissimilar metals, repairing geometric tolerance defects to extend expensive part life and additive manufacturing across a variety of industries. Expensive helium is used to accelerate the particles to higher velocities in order to achieve the highest deposit strengths and to spray hard-to-deposit materials. Minimal information is available in the literature studying the effects of He-N2 mixing on coating deposition efficiency, and how He can potentially be conserved by gas mixing. In this study, a one-dimensional simulation method is presented for estimating the deposition efficiency of aluminum coatings, where He-N2 mixture ratios are varied. The simulation estimations are experimentally validated through velocity measurements and single particle impact tests for Al6061.  相似文献   
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