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In this paper, the coordinate transformation method is used to analyze the aerosol particle deposition from a stagnation flow onto an axisymmetric wavy disk under to the coupling effects of Brownian diffusion, convection, sedimentation, thermophoresis and electrophoresis. The transformed governing equations obtained by coordinate transformation are solved by the spline alternating-direction implicit method. Numerical results show that electrophoresis will increase the particle deposition effect. It reveals that the thermophoresis effect of the cold wall will induce a driving effort to force particles toward the wall and accelerate the deposition onto the wall. When Brownian diffusion and thermophoresis dominate the particle deposition process, the influence of the lumpy surface geometry will become stronger with the increase of the disk radius, and the mean particle deposition effect of the wavy disk would be less than that of the flat disk.  相似文献   
2.
Horng JB  Chou WY  Tsau S  Liao J  Hsu SM  Chen CL  Chang KC  Su YK 《Applied optics》2007,46(5):680-684
We demonstrate the development of a simply equipped displacement sensor utilizing spatially dispersive confocal technology. It feeds the amplified spontaneous emission (ASE) of a laser diode to a wavelength-selective feedback structure that corresponds to the position of a measured surface. The displacement sensor has a detecting range of 4 microm and precision of less than 2 nm, as proven by the analysis of the spectral shifts of the multipassed amplified output ASE. As compared with traditional sensors, the displacement sensor presented in our study requires fewer components and has as high precision as complex systems and a higher measurement rate due to the simpler strategy of displacement determination.  相似文献   
3.
Microsystem Technologies - The main goal of this study addresses the synchronization between two MEMS resonators with cubic and quintic mechanical stiffness under the existence of system...  相似文献   
4.
This paper reviews both static and dynamic characteristics of a planar-type Pd–GaN metal–semiconductor–metal (MSM) hydrogen sensor. The sensing mechanism of a metal–semiconductor (MS) hydrogen sensor was firstly reviewed to realize the sensing mechanism of the proposed sensor. Symmetrically bi-directional current–voltage characteristics associated with our sensor were indicative of easily integrating with other electrical/optical devices. In addition to the sensing current, the sensing voltage was also used as detecting signals in this work. With regard to sensing currents (sensing voltages), the proposed sensor was biased at a constant voltage (current) in a wide range of hydrogen concentration from 2.13 to 10,100 ppm H2/N2. Experimental results reveal that the proposed sensor exhibits effective barrier height variations (sensing responses) of 134 (173) and 20 mV (1) at 10,100 and 2.13 ppm H2/N2, respectively. A sensing voltage variation as large as 18 V was obtained at 10,100 ppm H2/N2, which is the highest value ever reported. If an accepted sensing voltage variation is larger than 3 (5) V, the detecting limit is 49.1 (98.9) ppm. Moreover, voltage transient response and current transient response to various hydrogen-containing gases were experimentally studied. The new finding is that the former response time is shorter than the latter one. Other dynamic measurements by switching voltage polarity and/or continuously changing hydrogen concentration were addressed, showing the proposed sensor is a good candidate for commonly used MS sensors.  相似文献   
5.
This paper reports on new GaN sensors using a Pd-mixture-Pd triple-layer sensing structure to enhance their sensitivity to hydrogen at the tens of ppm level. The proposed hydrogen sensor biased with a constant voltage produced relatively high sensing responses of 4.84 × 105% at 10,100 ppm and 8.7 × 104% at 49.1 ppm H2 in N2. The corresponding barrier height variations are calculated to be 220 and 168 mV. When the sensor is biased by a constant current with maximum power consumption of 0.4 mW, a sensing voltage as an output signal showed a voltage shift of more than 17 V (the highest value ever reported) at 49.1 ppm H2 in N2. By comparison to Pd-deposited GaN sensors, the improvement in static-state performance is likely attributed to double dipole layers formed individually at the Pd–GaN interface and inside the mixture. Moreover, voltage transient response and current transient response to various hydrogen-containing gases were experimentally studied. The new finding is that the former response time is shorter than the latter one.  相似文献   
6.
Nowadays customers choose products strictly in terms of their specific demands. How to quickly and accurately catch customers’ feelings and transform them into design elements and vice versa becomes an important issue. This study explores the bi-directional relationship between customers’ demands or needs and product forms by using a novel integral approach. High-price machine tools are used as our demonstration target. This integral approach adopts the “grey system theory (GST)”, and the state-of-the-art machine learning based modeling formalism “support vector regression (SVR)” in the “Kansei engineering (KE)” process. The GST is used to effectively determine the influence weighting of form parameters on product images and the SVR is used to precisely establish the mapping relationship between product form elements and product images. Furthermore, for practical concerns, a user-friendly design hybrid design expert system was developed based on the proposed novel integral schemes.  相似文献   
7.
We demonstrate a novel all-optical noninverted OC-192 return-to-zero (RZ) decision-gate by using a semiconductor optical amplifier (SOA) which is gain-controlled to achieve an extremely high cross-gain-modulation depth and a narrow gain window. A dark-optical-comb generated by reshaping the optical clock RZ data in a Mach-Zehnder intensity modulator is employed as an injecting source to temporally deplete most of the gain in the SOA. Such a dark-optical-comb injected SOA decision-gate exhibits improved 3R regeneration performances such as a timing tolerance of 33.5 ps, Q -factor of 8.1, an input dynamical tolerance of 14 dB, and an extinction ratio (ER) of 14 dB. The deviation between the wavelengths of backward injected dark-optical-comb and input RZ data for optimizing the ER of the decision-gate is determined as Deltalambda=19 nm. Under a threshold operating dark-optical-comb power of 7 dBm, such a decision-gate can recover the -18.5-dBm degraded RZ data with a bit-error-rate of less than at 10-9 Gb/s. A negative power penalty of -4.2 dB is demonstrated for the RZ data after 50-km propagation and decision gating.  相似文献   
8.
Excessive glutamate release is known to be involved in the pathogenesis of neurological diseases, and suppression of glutamate release from nerve terminals is considered to be a treatment strategy. In this study, we investigated whether isosaponarin, a flavone glycoside isolated from wasabi leaves, could affect glutamate release in rat cerebral cortex nerve terminals (synaptosomes). The release of glutamate was evoked by the K+ channel blocker 4-aminopyridine (4-AP) and measured by an online enzyme-coupled fluorimetric assay. Isosaponarin produced a concentration-dependent inhibition of 4-AP-evoked glutamate release with a half-maximum inhibition of release value of 22 μM. The inhibition caused by isosaponarin was prevented by eliminating extracellular Ca2+ or by using bafilomycin A1, an inhibitor of synaptic vesicle exocytosis. Isosaponarin decreased intrasynaptosomal rises in Ca2+ levels that were induced by 4-AP, without affecting the synaptosomal membrane potential. The isosaponarin-induced inhibition of glutamate release was significantly prevented in synaptosomes that were pretreated with a combination of the calcium channel blockers ω-conotoxin GVIA (N-type) and ω-agatoxin IVA (P/Q-types). The protein kinase C (PKC) pan-inhibitor GF109203X and the Ca2+-dependent PKC inhibitor Go6976 abolished the inhibition of glutamate release by isosaponarin, while the Ca2+-independent PKC inhibitor rottlerin did not show any effect. The results from immunoblotting assays also showed that isosaponarin lowered PKC, PKCα, synaptosomal-associated protein of 25 kDa (SNAP-25), and myristoylated alanine-rich C-kinase substrate (MARCKS) phosphorylation induced by 4-AP. In addition, FM1-43-labeled synaptic vesicles in synaptosomes showed that treatment with isosaponarin resulted in an attenuation of the 4-AP-induced decrease in fluorescence intensity that is consistent with glutamate release. Transmission electron microscopy of synaptosomes also provided evidence that isosaponarin altered the number of synaptic vesicles. These results indicate that isosaponarin suppresses the Ca2+-dependent PKC/SNAP-25 and MARCKS pathways in synaptosomes, causing a decrease in the number of available synaptic vesicles, which inhibits vesicular glutamate release from synaptosomes.  相似文献   
9.
The mobility of the popular goods on the shelves will have a crucial impact on the store sales. For retailers, the seasonal or news-induced demand for commodity will have the flocking effect or business opportunity lasting for some time; if the product shortage occurs, consumers will immediately turn to other stores, and the sale opportunity will be missed.Traditionally, to confirm the demand for commodity, the stores primarily employ the point-of-sale (POS) system to monitor the inventory of goods, but the turnover rate of popular goods is very demanding. The inventory information supplied by the POS system is that generated after the ledger-closing stage, and it cannot precisely match the actual quantity of goods on the shelves. Therefore, in order to prevent the monetary loss due to the information gap, we propose the “intelligent service-integrated platform”, which employs the software agent as the framework to construct the integrated information system mechanism. We also employ the radio frequency identification (RFID) technology to realize the smart shelf as the trigger point for the retrieval of commodity message. At the same time, we develop the interactive information platform to provide the consultation and promotion service of goods. The overall framework will help enhance the performance of the sales outlets and improve the customer service, while addressing the time effect issue of the popular commodity.  相似文献   
10.
A complementary electrochromic device (ECD) based on Prussian blue (PB) and poly(3,3-diethyl-3,4-dihydro-2H-thieno-[3,4-b][1,4]dioxepine) (PProDOT-Et2) has been systematically investigated. PB is regarded as an anodic coloring material with high electrochemical stability, while PProDOT-Et2 is a cathodic coloring polymer with high contrast and high coloration efficiency (η). The electro-optical properties of the two electrochromic (EC) materials are characterized separately in a 0.1 M LiClO4 in propylene carbonate (PC). A complementary ECD is assembled based on the two EC materials. The maximum transmittance of the ECD at 590 nm can be changed reversibly from 11.3% to 70.6% at the applied voltages of 1.2 and −1.3 V, and achieved a high coloration efficiency of 1214 cm2/C. Moreover, this ECD still remains at 98% of its maximum transmittance window (ΔTmax) even after 1,200 cycles, namely, the ΔT value decreases from 59% to 58%.  相似文献   
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