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1.
In the context of nonlinear dynamic system identification for Hammerstein systems, Rollins et al. (2003a) studied the information efficiency of the following two competing experimental design approaches: statistical design of experiments (SDOE) and pseudo-random sequences design (PRSD). The focus of this study is the Wiener system and evaluates SDOE against PRS under D-optimal efficiency. Three cases are evaluated and the results strongly support SDOE as the better approach.  相似文献   
2.
Wireless Personal Communications - Scheduling in computing environments such as homogeneous and heterogonous is very challenging and faces various difficulties computationally. This computing needs...  相似文献   
3.
The present article is concerned with the investigation of disturbances in a homogeneous transversely isotropic thermoelastic rotating medium with two temperatures, in the presence of the combined effects of Hall currents and magnetic field. The formulation is applied to the thermoelasticity theories developed by Green-Naghdi theories of type-II and type-III. Laplace and Fourier transform techniques are applied to solve the problem. The analytical expressions of displacements, stress components, temperature change, and current density components are obtained in the transformed domain. A numerical inversion technique has been applied to obtain the results in the physical domain. Numerical simulated results are depicted graphically to show the effect of Hall current and two temperatures on resulting quantities. Some special cases are also deduced from the present investigation.  相似文献   
4.
The goal of this work is to present a causation modeling methodology with the ability to accurately infer blood glucose levels using a large set of highly correlated noninvasive input variables over an extended period of time. These models can provide insight to improve glucose monitoring, and glucose regulation through advanced model-based control technologies. The efficacy of this approach is demonstrated using real data from a type 2 diabetic (T2D) subject collected under free-living conditions over a period of 25 consecutive days. The model was identified and tested using eleven variables that included three food variables as well as several activity and stress variables. The model was trained using 20 days of data and validated using 5 days of data. This gave a fitted correlation coefficient of 0.70 and an average absolute error (AAE) (i.e., the average of the absolute values for the measured glucose concentration minus modeled glucose concentration) of 13.3 mg/dL for the validation data. This AAE result was significantly better than the subject’s personal glucose meter AAE of 15.3 mg/dL for replicated measurements.  相似文献   
5.
It was aimed to explore the potential of abrasives in nanometer size in friction materials (FMs). Hence six FMs were developed using micro and nano-abrasives of three types viz. alumina, SiC and silica (2%). The nano and micro composites were developed and characterized for various physical and chemical properties. The tribological performance was evaluated on a reduced scale prototype under various operating parameters and output parameters such as wear, μavg as a function of speed and pressure, load-speed sensitivity of μ and friction stability were considered to compare the performance of nano and micro-composites (NCs and MCs). It was concluded that all performance parameters were significantly and beneficially affected due to nano-fillers. Nano-silica proved to impart highest wear resistance followed by SiC and then alumina while best combination of friction properties was exhibited by composites with SiC followed by Alumina and then silica. SEM on worn surfaces of pads and discs was done to understand wear mechanism and it was clearly observed that thin coherent film on both the surfaces in case of NCs was responsible for enhanced performance.  相似文献   
6.
Nath N  Chilkoti A 《Analytical chemistry》2004,76(18):5370-5378
The unique optical properties of noble metal nanoparticles have been used to design a label-free biosensor in a chip format. In this paper, we demonstrate that the size of gold nanoparticles significantly affects the sensitivity of the biosensor. Gold nanoparticles with diameters in the range of 12-48 nm were synthesized in solution and sensor chips were fabricated by chemisorption of these nanoparticles on amine-functionalized glass. Sensors fabricated from 39-nm-diameter gold nanoparticles exhibited maximum sensitivity to the change of the bulk refractive index and the largest "analytical volume", defined as the region around the nanoparticle within which a change in refractive index causes a change in the optical properties of the immobilized nanoparticles. The detection limit for streptavidin-biotin binding of a sensor fabricated from 39-nm-diameter nanoparticles was 20-fold better than a previously reported sensor fabricated from 13-nm-diameter gold nanoparticles. We also discuss several other factors that could improve the performance of the next generation of these immobilized metal nanoparticle sensors.  相似文献   
7.
A novel SiX–dipropargyl glycerol scaffold (X: H, F, or 18F) was developed as a versatile prosthetic group that provides technical advantages for the preparation of dimeric radioligands based on silicon fluoride acceptor pre‐ or post‐labeling with fluorine‐18. Rapid conjugation with the prosthetic group takes place in microwave‐assisted click conjugation under mild conditions. Thus, a bivalent homodimeric SiX–dipropargyl glycerol derivatized radioligand, [18F]BMPPSiF, with enhanced affinity was developed by using click conjugation. High uptake of the radioligand was demonstrated in 5‐HT1A receptor‐rich regions in the brain with positron emission tomography. Molecular docking studies (rigid protein–flexible ligand) of BMPPSiF and known antagonists (WAY‐100635, MPPF, and MefWAY) with monomeric, dimeric, and multimeric 5‐HT1A receptor models were performed, with the highest G score obtained for docked BMPPSiF: ?6.766 as compared with all three antagonists on the monomeric model. Multimeric induced‐fit docking was also performed to visualize the comparable mode of binding under in vivo conditions, and a notably improved G score of ?8.455 was observed for BMPPSiF. These data directly correlate the high binding potential of BMPPSiF with the bivalent binding mode obtained in the biological studies. The present study warrants wide application of the SiX–dipropargyl glycerol prosthetic group in the development of ligands for imaging with enhanced affinity markers for specific targeting based on peptides, nucleosides, and lipids.  相似文献   
8.
Lutein and zeaxanthin are selectively accumulated in the macula of the retina, yet their bioavailability is influenced by various dietary factors. Insights regarding the effects of dietary lipids on lutein micellization that is available for absorption are limited. This study investigated the influence of vegetable oils on the relative efficiency of lutein micellization using in vitro digestion procedure. Lutein dispersed in either olive oil (OO), corn oil (CO), soybean oil (SBO), sunflower oil (SFO), groundnut oil (GNO), rice bran oil (RBO) or palm oil (PO) was subjected to simulated gastric and small intestinal digestion. Results showed that the efficiency of micellization of lutein dispersed in olive oil exceeds the other vegetable oils. The percent lutein micellization was in the order of OO > GNO > RBO > SFO > CO > SBO > PO. In comparison, the values for OO were higher than GNO (11%), RBO (18.3%), SFO (19%), CO (21.7%), SBO (30.5%) and PO (35.2%), respectively. These results suggest that OO rich in oleic acid may favor the incorporation of lutein into micelles at the intestinal level. To conclude, the type of vegetable oil in which carotenoids are dispersed is important to achieve an enhanced bioavailable lutein. The correlation between the micellizable lutein and fatty acid composition of vegetable oils are discussed.  相似文献   
9.
The processing parameters have been optimized to achieve highly pure and fully dense pellets of calcium cobalt oxide (Ca3Co4O9) from solid-state ball milled calcium carbonate and cobalt oxide mixtures, calcined at optimized temperature and time, and consolidated by hot-pressing. The microscopic, spectroscopic, and thermal analysis suggest samples with longer ball-milling time require less calcination time for synthesizing highly pure crystalline phases of Ca3Co4O9, and provide 99.2 ± 0.5% relative density.  相似文献   
10.
Two-dimensional MoS2 nanoparticles (2D-nps) exhibit artificial enzyme properties that can be regulated at bio-nanointerfaces. We discovered that protein lipase is able to tune the peroxidase-like activity of MoS2 2D-nps, offering low-nanomolar, label-free detection and identification in samples with unknown identity. The inhibition of the peroxidase-like activity of the MoS2 2D-nps was demonstrated to be concentration dependent, and as low as 5 nm lipase was detected with this approach. The results were compared with those obtained with several other proteins that did not display any significant interference with the nanozyme behavior of the MoS2 2D-nps. This unique response of lipase was characterized and exploited for the successful identification of lipase in six unknown samples by using qualitative visual inspection and a quantitative statistical analysis method. The developed methodology in this approach is noteworthy for many aspects; MoS2 2D-nps are neither labeled with a signaling moiety nor modified with any ligands for signal readout. Only the intrinsic nanozyme activity of the MoS2 2D-nps is exploited for this detection approach. No analytical equipment is necessary for the visual detection of lipase. The synthesis of the water-soluble MoS2 2D-nps is low costing and can be performed in bulk scale. Exploring the properties of 2D-nps and their interactions with biological materials reveals highly interesting yet instrumental features that offer the development of novel bioanalytical approaches.  相似文献   
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