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1.
A desktop study has been performed to analyse the performance of biomass-to-fuel plants producing methanol, dimethylether (DME) or hydrogen. Two different designs have been made. One design based on the technology of today and one design based on the technology of tomorrow. Mass and energy balances are presented for both designs producing all three fuels. Biomass-to-fuel conversion efficiencies (LHV) of the plants range between 45 and 56% for hydrogen and DME production respectively in the present-day design and between 56 and 69% for hydrogen and methanol production respectively for the near-future design. Biomass-to-fuel conversion efficiency to DME is only marginally smaller than biomass-to-fuel conversion efficiency of methanol. Expression of efficiency of the biomass-to-fuel plant in biomass-to-fuel conversion efficiency does not include electrical power consumption and district heat generation. Exergy also includes the quality of the energy that is consumed or generated. Therefore exergetic efficiency should be used to express process efficiency. Methanol production using the technology of tomorrow is most efficient with exergetic efficiency of 55%. The least efficient is hydrogen production with exergetic efficiency of 40% and 45%, for present-day and near-future design, respectively. This is caused by the large purge stream in the plant design. The use of new technologies developed within the CHRISGAS project give an increase of 5–8% points in exergetic efficiency.  相似文献   
2.
At present, flexible displays are an important focus of research. Further development of large, flexible displays requires a cost-effective manufacturing process for the active-matrix backplane, which contains one transistor per pixel. One way to further reduce costs is to integrate (part of) the display drive circuitry, such as row shift registers, directly on the display substrate. Here, we demonstrate flexible active-matrix monochrome electrophoretic displays based on solution-processed organic transistors on 25-microm-thick polyimide substrates. The displays can be bent to a radius of 1 cm without significant loss in performance. Using the same process flow we prepared row shift registers. With 1,888 transistors, these are the largest organic integrated circuits reported to date. More importantly, the operating frequency of 5 kHz is sufficiently high to allow integration with the display operating at video speed. This work therefore represents a major step towards 'system-on-plastic'.  相似文献   
3.
This paper presents an historical survey of the basis for design wind pressure used by 19th and early 20th century engineers. Events significant to the development of current wind design standards for pedestrian bridges are explored. These include 19th century treatments of wind load, a review of bridge disasters that spurred new thinking, and historical developments of today’s standards.  相似文献   
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We report a case of Bellini duct carcinoma of the left kidney with invasive growth pattern. A 39-year-old man was admitted to our hospital with the chief complaint of gross hematuria. Ultrasonography showed left renal swelling but normal reniform configuration of the kidney was maintained. Computed tomography demonstrated a low density tumor infiltrating into the renal cortex and with tumor extension into the renal vein. Renal angiography revealed a hypovascular tumor. We suspected a left renal cell carcinoma with tumor extension into the left renal vein, and performed radical nephrectomy. Macroscopically, the resected kidney had a normal outer contour. The tumor with infiltrative growth pattern existed in renal medulla. Histopathologic examination revealed a papillary adenocarcinoma originated in Bellini duct (pT3bN2M0). The patient underwent systemic chemotherapy (M-VAC). This case showed invasive growth pattern, which were different from the usual renal cell carcinoma and Bellini duct carcinoma.  相似文献   
6.
Researchers often have expectations about the research outcomes in regard to inequality constraints between, e.g., group means. Consider the example of researchers who investigated the effects of inducing a negative emotional state in aggressive boys. It was expected that highly aggressive boys would, on average, score higher on aggressive responses toward other peers than moderately aggressive boys, who would in turn score higher than nonaggressive boys. In most cases, null hypothesis testing is used to evaluate such hypotheses. We show, however, that hypotheses formulated using inequality constraints between the group means are generally not evaluated properly. The wrong hypotheses are tested, i.e.. the null hypothesis that group means are equal. In this article, we propose an innovative solution to these above-mentioned issues using Bayesian model selection, which we illustrate using a case study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Magnetic gears offer several advantages compared to mechanical gears in terms of reduced maintenance, improved reliability, and inherent overload protection while having a high efficiency. This paper describes the principle of operation of a novel form of magnetic gear, which is particularly suited to applications for which a high gear ratio is required. The performance capability of such a magnetic gear is investigated, and it is shown that it transmits a ripple-free torque and that an active torque density of up to 150 $hbox{kN}cdot hbox{m/m}^{3}$ per stage can be achieved when high-energy permanent magnets are employed. Simulation results on this novel gear are verified by experimental measurements on a prototype.   相似文献   
9.
Substantial improvements of the absolute photoluminescence quantum yield (QY) for surfactant‐free silicon nanocrystals (Si‐ncs) by atmospheric pressure microplasma 3‐dimensional surface engineering are reported. The effect of surface characteristics on carrier multiplication mechanisms is explored using transient induced absorption and photoluminescence QY. Surface engineering of Si‐ncs is demonstrated to lead to more than 120 times increase in the absolute QY (from 0.1% up to 12%) within an important spectral range of the solar emission (2.3–3 eV). The Si‐ncs QY is shown to be stable when Si‐ncs are stored in ethanol at ambient conditions for three months.  相似文献   
10.
The design of an 8-bit CMOS A/D converter is described which is intended for embedded operation in VLSI chips for video applications. The requirements on accuracy are analyzed and a comparator circuit is shown which realizes a high bandwidth. The full-flash architecture operates on wideband signals like CVBS in television systems. The A/D converter core measures 2.8 mm2 in a 1 μm CMOS process. The embedded operation of the A/D converter is illustrated on a video line-resizing chip  相似文献   
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