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991.
Dreaming of developing the Thames Estuary, Ian Abley and Jonathan Schwinge went to see the Maunsell Sea Forts, built off the coast of Herne Bay, Kent, in 1942. Here they met members of Project Redsand, a charitable organisation that aims to preserve the forts as a public museum, and which has so far received encouragement from both industry and government departments. 相似文献
992.
993.
电弧炉粉尘等温还原的动力学研究 总被引:7,自引:0,他引:7
为使还原条件与实际电弧炉生产相接近,在等温条件下对电弧炉粉尘球团的还原过程动力学进行了研究。电弧炉粉尘与还原剂碳和粘接剂石灰均匀混合后制粒,经干燥后将球闭置于恒定温度的加热炉中,利用电子称定时对球团重量进行检测。金属还原率的计算中,考虑了球团的失重、铅和锌在高温下挥发。经研究,电弧炉粉尘的还原分为二个阶段,还原初期由化学反应控制而还原后期由扩散控制,并建立了每一阶段的还原动力学方程,确定了有关的动力学参数表观活化能和频率因子。 相似文献
994.
Fabrication of Long Lengths of Epitaxial Buffer Layers on Biaxially Textured Nickel Substrates Using a Continuous Reel-to-Reel Dip-Coating Unit 总被引:2,自引:0,他引:2
M. Parans Paranthaman Thomas G. Chirayil Fred A. List Xingtian Cui Amit Goyal Dominic F. Lee Eliot D. Specht Patrick M. Martin Robert K. Williams Donald M. Kroeger Jonathan S. Morrell David B. Beach Ron Feenstra David K. Christen 《Journal of the American Ceramic Society》2001,84(2):273-78
A low-cost, nonvacuum, solution precursor route has been developed to produce epitaxial oxide buffer layers of Eu2 O3 or La2 Zr2 O7 on biaxially textured Ni (100) tapes. A reel-to-reel continuous dip-coating unit consisting of a constant-tension tape transport system attached to a controlled atmosphere furnace was fabricated. Nickel tapes were pulled through a 2-methoxyethanol solution of europium methoxyethoxide/acetate or lanthanum zirconium methoxyethoxide. The double-sided dip-coated tapes were then annealed in a preheated furnace at 1000°–1100°C with a high flow rate of Ar/H2 (4%) gas. The dip-coated buffers were dense, continuous, crack-free, and epitaxial with a single cube texture. A critical current ( J c ) of >1 MA/cm2 at 77 K and self-field was obtained for YBa2 Cu3 O7-δ (YBCO) films with a layer sequence of YBCO ( ex situ BaF2 process)/CeO2 (sputtered)/YSZ (sputtered)/Eu2 O3 (dip-coated)/nickel. We have produced 1–2 m lengths of epitaxial buffer layers on textured nickel substrates using a nonvacuum process for the first time. 相似文献
995.
H. Jonathan Chao Cheuk H. Lam Xiaolei Guo 《International Journal of Communication Systems》2001,14(7):663-678
Input–output queued switches have been widely considered as the most feasible solution for large capacity packet switches and IP routers. In this paper, we propose a ping‐pong arbitration scheme (PPA) for output contention resolution in input–output queued switches. The challenge is to develop a high speed and cost‐effective arbitration scheme in order to maximize the switch throughput and delay performance for supporting multimedia services with various quality‐of‐service (QoS) requirements. The basic idea is to divide the inputs into groups and apply arbitration recursively. Our recursive arbiter is hierarchically structured, consisting of multiple small‐size arbiters at each layer. The arbitration time of an n‐input switch is proportional to log4?n/2? when we group every two inputs or every two input groups at each layer. We present a 256×256 terabit crossbar multicast packet switch using the PPA. The design shows that our scheme can reduce the arbitration time of the 256×256 switch to 11 gates delay, demonstrating the arbitration is no longer the bottleneck limiting the switch capacity. The priority handling in arbitration is also addressed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
996.
A nonlinear heat equation which models the microwave assisted joining of two large SiC tubes is analyzed. By exploiting the small fineness ratio of the structure and disparate time scales an asymptotic theory for this problem is systematically deduced. Specifically, a one-dimensional nonlinear heat equation is described which governs the temperature in the outer region. This is a numerically well posed problem and it is efficiently solved using standard methods. This solution is not valid in the inner region which includes the microwave source. An inner asymptotic approximation is derived to describe the temperature in this region. This approximation yields two unknown functions which are determined from matching to the outer solution. The results of the asymptotic theory are compared to calculations done on the full problem. Since the full problem is numerically ill conditioned, the asymptotic theory yields enormous savings in computational time and effort. 相似文献
997.
电弧炉粉尘球团直接还原的热传导模型 总被引:1,自引:0,他引:1
对电弧炉炼钢粉尘加上还原剂碳混合制粒成的球团还原过程的热传导行为进行了研究,根据实验推导了球团导热模型的结构参数,并试图建立热传导模型。 相似文献
998.
Electric arc furnace dust non-isothermal reduction kinetics 总被引:3,自引:0,他引:3
1 INTRODUCTIONTheairbornefineparticulateElectricArcFur nace (EAF)dustisgeneratedinthesteelmanufactur ingprocesswhenscrapiselectricallymelted .Itisconsideredasahazardouswastebecauseofleachingcharacteristicofheavymetalssuchaslead ,zincandchromium ,whichare p… 相似文献
999.
Martin Harrow; Jonathan Himmelhoch; Gary Tucker; Jane Hersh; Donald Quinlan 《Canadian Metallurgical Quarterly》1972,79(2):161
Investigated 2 types of overinclusive thinking, behavioral and conceptual, in 110 acute psychiatric inpatients. The Object Sorting Test was administered and scored for the 2 types of overinclusion and for idiosyncratic (bizarre) thinking and rich associations. Results on behavioral overinclusion and rich associations were mixed. Behavioral overinclusion was more frequent in schizophrenics, but was also found in many acute nonschizophrenics. Conceptual overinclusion and idiosyncratic thinking were significantly more frequent among acute schizophrenics and were also found in delusional patients regardless of diagnosis. (41 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Wastewater aeration basins at publicly owned treatment works (POTWs) can be emission sources for gaseous or aerosolized sewage material. In the present study, particle and gas phase emissions of synthetic musks from covered and uncovered aeration basins were measured. Galaxolide (HHCB), tonalide (AHTN), and celestolide (ADBI) were the most abundant, ranging from 6704 to 344,306 ng m−3, 45-3816 ng m−3, and 2-148 ng m−3 in the gas phase with particle phase concentrations 3 orders of magnitude lower. The musk species were not significantly removed from the exhaust air by an odor control system, yielding substantial daily emission fluxes (∼200 g d−1 for HHCB) into the atmosphere. However, simple dispersion modeling showed that the treatment plants are unlikely to be a major contributor to ambient air concentrations of these species. Emission of synthetic musk species during wastewater treatment is a substantial fate process; more than 14% of the influent HHCB is emitted to the atmosphere in a POTW as opposed to the <1% predicted by an octanol-water partition coefficient and fugacity-based US EPA fate model. The substantial atmospheric emission of these compounds is most likely due to active stripping that occurs in the aeration basins by bubbling air through the sludge. 相似文献