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161.
Ink drops have to be filled into the square cells for an electrowetting display panel. Several ink solutions such as dodecane, tetradecane, and hexadecane were used as test liquids. These fluids have viscosities less than 4 mPas and surface tensions between 23.3 and 26 mN/m and contact angles less than 50°. A slot coating die was employed to deliver these liquids to fill up the square cells. The effects of several parameters such as coating thickness and coating speed were examined. Operating windows inside which the stable filling is possible could be found for these liquids. Several defects were observed outside the operating windows. A flow visualization technique was applied to observe the fluid motion in the coating bead region, particularly the movements of upstream and downstream menisci, the mechanism of liquid filling was discussed.  相似文献   
162.
Three-dimensional molecular dynamics (MD) simulations of nanojet ejection with different aperture shapes are reported. The simulations use the Lennard-Jones 12-6 (LJ) potential to describe the intermolecular interaction. Using non-equilibrium MD, argon nanojet ejection is simulated under vacuum conditions. According to the analysis, different aperture shapes influence the ejection processes. The ejection speeds were 23.7 and 63.2?m/s respectively in the simulation. The speed of spurting atoms in type A nanojet was slower than the other types and it became more obvious when the process time increased. The variations in velocity, density, pressure, and temperature were found with the aid of MD. The liquid temperatures were set at 50, 100, 150, and 200?K, respectively, to examine nanojet break-up characteristics. The liquid temperature inside the nanojet was found to be a factor that induce break-up. A higher temperature led to faster nanojet break-up.  相似文献   
163.
Vertically aligned ZnO nanorods (NRs) on aluminum-doped zinc oxide (AZO) substrates were fabricated by a single-step aqueous solution method at low temperature. In order to optimize optical quality, the effects of annealing on optical and structural properties were investigated by scanning electron microscopy, X-ray diffraction, photoluminescence (PL), and Raman spectroscopy. We found that the annealing temperature strongly affects both the near-band-edge (NBE) and visible (defect-related) emissions. The best characteristics have been obtained by employing annealing at 400°C in air for 2 h, bringing about a sharp and intense NBE emission. The defect-related recombinations were also suppressed effectively. However, the enhancement decreases with higher annealing temperature and prolonged annealing. PL study indicates that the NBE emission is dominated by radiative recombination associated with hydrogen donors. Thus, the enhancement of NBE is due to the activation of radiative recombinations associated with hydrogen donors. On the other hand, the reduction of visible emission is mainly attributed to the annihilation of OH groups. Our results provide insight to comprehend annealing effects and an effective way to improve optical properties of low-temperature-grown ZnO NRs for future facile device applications.  相似文献   
164.
Iron powder was coated with phosphate and polysiloxanes for anti-corrosion and insulation. Whether these coating layers sustain the hydraulic pressure of compaction was investigated. Electrochemical measurements were applied on the compacts comprising surface-coated iron powders to understand the performance of the coating layers undergone a series of compaction pressure. As phosphate coating was applied, the corrosion resistance was obviously enhanced; nevertheless, as the compaction pressure exceeded a threshold, the corrosion resistance dropped greatly due to the formation of cracks in the phosphate layer, suggesting the phosphate layer was brittle and could not bear high pressure. As a phosphate layer and a polymeric coating layer of amino polysiloxane were in turn applied, the corrosion resistance of the doubly-coated iron powder in the salt bath declined since the ammonium group absorbed chloride ions and deteriorated the anti-corrosion ability. After salt-fog treatment, the compacts with the grafted silane tended to form the rust layer with akaganeite phase while these without grafted silane did not, attesting that the polysiloxane did attract chloride ions. Interestingly, with the existence of polysiloxane, the cracking of the phosphate layer was effectively avoided. The polysiloxane layer could protect the underneath phosphate layer from cracking. Moreover, with the increase of compaction pressure, the corrosion resistance of the doubly-coated iron powder gradually increased due to the densification of the polysiloxane layer, which consequently hindered the chloride ions from diffusion into the surface of the iron particle.  相似文献   
165.
Three new 8-alkylcoumarins, 7-O-methylphellodenol-B (1), 7-methoxy-8-(3-methyl-2,3-epoxy-1-oxobutyl)chromen-2-one (2), and 3′-O-methylvaginol (3), together with seven known compounds (4–10) were isolated from the fruits of Cnidium monnieri. Their structures were determined by detailed analysis of spectroscopic data and comparison with the data of known analogues. All the isolates were evaluated the cytoprotective activity by MTS cell proliferation assay and the results showed that all the three new 8-alkylcoumarins exhibited cytoprotective effect on Neuro-2a neuroblastoma cells injured by hydrogen peroxide.  相似文献   
166.
This study investigates the influence of blood vessels on temperature distribution during high-intensity focused ultrasound (HIFU) ablation of liver tumors. A three-dimensional acoustics-thermal-fluid coupling model is simulated to compute the temperature field in the hepatic cancerous region. The model is based on the linear Westervelt and bioheat equations as well as the non-linear Navier–Stokes equations for the liver parenchyma and blood vessels. The effect of acoustic streaming is also taken into account in the present HIFU simulation study. We found from this three-dimensional coupling study that in large blood vessel both the convective cooling and acoustic streaming can significantly change the temperature field and thermal lesion near blood vessels.  相似文献   
167.
This paper investigates a method for conducting conventional ultrasound image scanning (C-scan) in a non-immersive manner. An ultrasound coupling device is developed to couple a focusing ultrasound transducer with a sample under test through a water droplet. The transducer is immersed in a chamber filled with water. A hole-opening at the chamber’s bottom surface and a polymer film sealing the hole allow focused ultrasound to pass and reach the sample through a water droplet. An ultrasound scanning system is constructed and used for carrying out C-scan on two different samples containing pre-fabricated internal defects. By comparing the images obtained from using both conventional water immersion method and the proposed water-droplet coupling method, we demonstrate the feasibility and capability of this new type of non-immersive ultrasound image scanning method.  相似文献   
168.
People are now living longer because of advances in medical science, resulting in the percentage of the elderly in the population increasing year by year. These older individuals cannot move about like youngsters do. Internet shopping could become one of the most important shopping channels for them. According to related domestic and foreign survey results, this is confirmed by the increased percentage of elderly Internet shoppers. A lot of consumers, however, are still not satisfied with their Internet shopping experiences. Many have had the experience of giving up before completing the purchasing procedure. The key factors included in such procedures are rather complex, and user interfaces are not necessarily well‐designed. Nowadays, most websites are still designed for the convenience of the seller instead of the consumers. Often consumers find that their interfaces are complex and hard to use and that they require a high mental workload. Based on the behavioral model of older Internet consumers and difficulties they have encountered, and after exploring the information provided by shopping websites and evaluating the status of their current interface design, this study proposes an example of a supporting interface design system (SIDS) for the elderly. The effects of the SIDS are verified experimentally. A total of 12 subjects participated in the experiment. The results showed that the SIDS could successfully reduce the time spent by the elderly subjects on inputting data during the shopping process and the number of repetitions and the time spent on searching for, examining, and comparing products. Furthermore, it was also helpful to reduce the mental workload caused by Internet shopping. © 2012 Wiley Periodicals, Inc.  相似文献   
169.
170.
随着"五大"体系建设的深入推进,由于缺乏相应的执行管控体系和信息化支撑手段,当前省级电网公司投资管理工作已不能满足提升投资管理精益化的要求。从信息化系统建设角度,分析了省级电网公司投资管理信息化支撑存在的问题,提出了"投资管理一体化信息平台"的总体构架,从总体系统应用架构、总体系统集成和总体技术路线3个方面,设计了技术解决方案,并基于ERP信息系统,实现了该信息平台的应用开发。  相似文献   
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