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51.
52.
The physicochemical properties of binary and ternary fat systems made of commercial samples of palm oil (PO) blended with anhydrous milk fat (AMF) and/or rapeseed oil (RO) were studied. Physical properties such as solid fat content by pulsed‐Nuclear Magnetic Resonance (p‐NMR), melting profile by differential scanning calorimetry (DSC), and polymorphism of the blends were investigated. Palm oil was then batch enzymatically interesterified for 27 h, using Lipozyme® TL IM as biocatalyst, and further blended with AMF and/or RO in the same way. The objective of the present work was to evaluate the effect of batch enzymatic interesterification (B‐EIE) of palm oil on physical characteristics of the investigated fat blends. For that purpose, iso‐solid diagrams have been constructed from p‐NMR data. It was shown that B‐EIE of palm oil modifies its melting behaviour, but also its polymorphic stability and miscibility with other fats. Under dynamic conditions, after B‐EIE, the non‐ideal behaviour (eutectic) detected at low temperatures in the ternary PO/AMF/RO system disappears in the corresponding EIE‐PO/AMF/RO. After static crystallization followed by a tempering, the hardness of palm oil is increased after B‐EIE, as well as the hardnesses of the blends containing this fat compared to the native one. Polymorphism stability of the binary and ternary fat systems is also modified after B‐EIE compared to the corresponding native systems.  相似文献   
53.
In this study, the semi-aromatic polyamide membranes were synthesized by the interfacial polymerization between piperazine (PIP) monomers in the water phase and Benzene-1,3,5-tricarbonyl chloride in the organic phase. To further modify the semi-aromatic pervaporation membrane, the two amino acids, glycine, and l -lysine, were mixed with PIP monomers for interfacial polymerization. The morphology and physicochemical properties of the synthesized membranes were analyzed using Fourier transform infrared (FTIR), field emission scanning electron microscope (FE-SEM), atomic force microscope (AFM), and contact angle measurements. The results show that the semi-aromatic polyamide membranes modified by the two amino acids possess a higher hydrophilic surface and lower thickness compared to the unmodified membrane. Additionally, the permeation flux of the semi-aromatic polyamide membranes was improved by 18.6% and 38.5% as modified with glycine and l -lysine, respectively, at the operating temperature of 70°C when the rejection of both NaCl and arsenic are higher than 99.8%. Furthermore, the operating temperature significantly influenced the permeation flux, while the salt rejections were insignificantly affected. The permeation flux increases by 3.2- and 4.0-folds for glycine and lysine-modified membranes, respectively, when elevating the feed temperature from 40°C to 70°C. The highest permeation flux of 29.5 kg m−2 h−1 with a 5 wt% NaCl rejection of 99.8% was obtained at 70°C by using 0.3 wt% l -lysine modified polyamide (PA) membrane. For elimination of 1.5 mg L−1 As solution at the feed temperature of 70°C, such l -lysine modified PA membrane exhibited the permeation flux of 30.5 kg m−2 h−1 and As rejection of 99.6%, respectively. This work provides a cost-saving, facile, and eco-friendly preparation method for effectively improving the permeation flux while not sacrificing the high rejection of salts of the modified membranes.  相似文献   
54.
A cluster topology was proposed with the assumption of zero noise to improve the performance of wireless body area networks (WBANs). However, in WBANs, the transmission power should be reduced as low as possible to avoid the effect of electromagnetic waves on the human body and to extend the lifetime of a battery. Therefore, in this work, we consider a bit error rate for a cluster‐based WBAN and analyze the performance of the system while the transmission of sensors and cluster headers (CHs) is controlled. Moreover, a hierarchical topology is proposed for the cluster‐based WBAN to further improve the throughput of the system; this proposed system is called as the hierarchical cluster WBAN. The hierarchical cluster WBAN is combined with a transmission control scheme, that is, complete control, spatial reuse superframe, to increase the throughput. The proposed system is analyzed and evaluated based on several factors of the system model, such as signal‐to‐noise ratio, number of clusters, and number of sensors. The calculation result indicates that the proposed hierarchical cluster WBAN outperforms the cluster‐based WBAN in all analyzed scenarios.  相似文献   
55.
Boundary matching algorithm (BMA) and decoder motion vector estimation (DMVE) are two well-known temporal error concealment methods using the matching-based approach. In these two methods, the motion vector of each missing block is estimated by choosing one among candidate motion vectors which minimizes a sum of absolute differences (SAD) between boundary pixels of the corrupted macroblock. In general, the performance of DMVE is better than that of BMA. However, depending on the location or pattern of the corrupted block, BMA produces higher visual quality than DMVE. In this paper, we propose two types of hybrid error concealment methods; switching method and blending method. The switching method chooses one of two results obtained by BMA and DMVE based on the normalized SAD values. In the blending method, the weighted sum of the results concealed by the aforementioned two methods is utilized to improve the performance of error concealment. In order to reduce blocking artifacts further, the modified overlapped-block motion compensation is adaptively applied to the concealed blocks. Simulation results show that the proposed methods outperform other techniques in terms of subjective visual quality as well as PSNR performance.  相似文献   
56.
The absolute concentration and the compartmentalization of analytes in cells and organelles are crucial parameters in the development of drugs and drug delivery systems, as well as in the fundamental understanding of many cellular processes. Nanoscale secondary ion mass spectrometry (NanoSIMS) imaging is a powerful technique which allows subcellular localization of chemical species with high spatial and mass resolution, and high sensitivity. In this study, we combined NanoSIMS imaging with spatial oversampling with transmission electron microscopy (TEM) imaging to discern the compartments (dense core and halo) of large dense core vesicles in a model cell line used to study exocytosis, and to localize 13C dopamine enrichment following 4–6 h of 150 μM 13C L-3,4-dihydroxyphenylalanine (L-DOPA) incubation. In addition, the absolute concentrations of 13C dopamine in distinct vesicle domains as well as in entire single vesicles were quantified and validated by comparison to electrochemical data. We found concentrations of 87.5 mM, 16.0 mM and 39.5 mM for the dense core, halo and the whole vesicle, respectively. This approach adds to the potential of using combined TEM and NanoSIMS imaging to perform absolute quantification and directly measure the individual contents of nanometer-scale organelles.  相似文献   
57.
A programmable intraocular CMOS pressure sensor system implant   总被引:1,自引:0,他引:1  
We present a programmable intraocular pressure sensor system implant integrated on a single CMOS chip. It contains an on-chip micromechanical pressure sensor array, a temperature sensor, readout and calibration electronics, a μC-based digital control unit, and an RF transponder. The transponder enables wireless data transmission and wireless power reception, thus making batteryless operation feasible. The chip has been fabricated in a 1.2-μm n-well CMOS process complemented by additional processing steps  相似文献   
58.
The catalytic conversion of CO2 into valuable fuels is a compelling solution for tackling the global warming and fuel crisis. Light absorption and charge separation, as well as adsorption/activation of CO2 on the photocatalyst surface, are essential steps for this process. This article reviews the CO2 photoreduction mechanisms and critical aspects that greatly affect the photoreduction efficiency. Additionally, different materials for CO2 photoreduction are provided, including d0 and d10 metal oxides/mixed oxides, sulfides, polymeric materials, and metal phosphides with visible response, metal‐organic frameworks, and layer double hydroxides. Furthermore, various structural engineering strategies and corresponding state‐of‐the‐art photocatalytic systems are reviewed and discussed, such as bandgap engineering, geometrical nanostructure engineering, and heterostructure engineering. Each strategy has advantages and disadvantages, requiring further adjustment to further improve the photocatalytic performance of the photocatalyst. Based on this review, it is greatly expected that efficiently artificial systems and the breakthrough technologies for CO2 reduction will be successfully developed in the future to solve the energy shortage as well as the environmental problem.  相似文献   
59.
Journal of Communications Technology and Electronics - The two-dimensional periodic dual-polarized antenna array in the form of a nonuniform multiconductor line of square cross-section conductors...  相似文献   
60.

Microscopic images are often corrupted by noise, where Poisson noise is one of the major types that can damage them. The local polynomial approximation (LPA) filter supported by the intersection confidence interval (ICI) rule was considered as an efficient filter for image de-noising. However, this filter depends on several parameters that affect its performance. In order to determine the optimal parameters, the present study employed the classic LPA-ICI (C-LPA-ICI) filter supported by optimization algorithms, namely the genetic algorithm (GA) and the particle swarm optimization (PSO) in the context of light microscopy imaging systems. Nevertheless, inclusion of the optimization algorithms increased the computational time. A novel automatic technique entitled “Standard Optimized LPA-ICI” (SO-LPA-ICI) is proposed. In this context, the average of the optimized ICI parameters was calculated, which obtained from both LPA-ICI-based GA (G-LPA-ICI) and LPA-ICI-based PSO (P-LPA-ICI). Thus, the proposed SO-LPA-ICI is included the optimal ICI parameters without optimization iterations. This procedure is proposed to speed up the optimized filter. A pool of 50 rats’ renal microscopic images is involved to test the proposed approach. A comparative study was conducted to compare the effectiveness of the four methods, namely C-LPA-ICI, G-LPA-ICI, P-LPA-ICI, and the SO-LPA-ICI for de-noising in the presence of Poisson noise. The experimental results established the outstanding performance of the SO-LPA-ICI in terms of the PSNR, MAE, and MSSIM with 28.27, 7.65, and 0.93 values, respectively. In addition, the proposed approach achieved fast de-noising compared to the G-LPA-ICI and the P-LPA-ICI.

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