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991.
Measures taken to develop and put into operation three new exterior channels for emergency process water with two additional
60VTs pumping units, which remain operational even during an earthquake and were installed in the second block pumping station,
are described. In addition, the three existing 12NDS horizontal pumping units were used as a basis to develop a third channel
for the emergency process water. Above-ground water ducts with thermal insulation and heating systems to prevent freezing
during the anticipation state, which is the constant state of the emergency system, were laid.
As a result of upgrading with the development of three channels, the emergency process water feeding reached an adequately
safe level of reliability.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 3, pp. 173–177, March, 2006. 相似文献
992.
Kargl F. Papadimitratos P. Buttyan L. Müter M. Schoch E. Wiedersheim B. Ta-Vinh Thong Calandriello G. Held A. Kung A. Hubaux J.-P. 《Communications Magazine, IEEE》2008,46(11):110-118
Vehicular communication systems are on the verge of practical deployment. Nonetheless, their security and privacy protection is one of the problems that have been addressed only recently. In order to show the feasibility of secure VC, certain implementations are required. In [1] we discuss the design of a VC security system that has emerged as a result of the European SeVe- Com project. In this second article we discuss various issues related to the implementation and deployment aspects of secure VC systems. Moreover, we provide an outlook on open security research issues that will arise as VC systems develop from today?s simple prototypes to fullfledged systems. 相似文献
993.
Panchaphongsaphak B. Riener R. Ullmer B. Burgkart R. Ravi N. 《Pervasive Computing, IEEE》2008,7(3):70-71
This issue's works in progress department features a novel technology that embeds a six-degrees-of-freedom force-torque sensor into a physical artifact to transform existing 3D passive artifacts into contact-sensitive interface devices. The department also presents an approach for rewriting binary to better correlate application usage with contextual information. 相似文献
994.
B. Kwakye‐Awuah I. Radecka M. A. Kenward C. D. Williams 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1255-1260
BACKGROUND: Metal‐exchanged zeolites have been reported to have significant limitations on cayalytic activity, such as counterbalancing the negative framework charges and limitation of active space. Alternative methods of incorporating silver ions into the framework of zeolites are therefore necessary. This paper reports on a technique for producing silver doped analcime by isomorphous substitution of silver ion into the framework of analcime. The amount of aluminium in the gel composition was reduced by a factor of 5%, 10% and 20% and an equivalent amount of silver was added to the gel and treated in a conventional manner for zeolite crystallisation. Some of the aluminium in the reaction gel was replaced with the silver. The silver‐doped analcime samples where characterised by X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X‐rays (EDX), Fourier transform infrared (FTIR) spectroscopy and inductively coupled plasma‐atomic emission spectroscopy (ICP‐AES) analysis. RESULTS: The amount of silver ions loaded for each reduction of aluminium as determined by EDX were found to be (w/w) 0.29%, 1.41% and 2.10%, respectively. XRD pattern SEM images of the silver‐doped analcime showed the presence of zeolite P in addition to analcime. CONCLUSION: Silver‐doped analcime was successfully produced with different silver loadings and may exhibit higher anti‐microbial activities than silver‐exchanged counterparts. Copyright © 2008 Society of Chemical Industry 相似文献
995.
Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
B. Basil Beamish 《Fuel》2008,87(1):125-130
Adiabatic self-heating tests have been conducted on subbituminous coal cores from the same seam profile, which cover a mineral matter content range of 11.2-71.1%. In all cases the heat release rate does not conform to an Arrhenius kinetic model, but can best be described by a third order polynomial. Assessment of the theoretical heat sink effect of the mineral matter in each of the tests reveals that the coal is less reactive than predicted using a simple energy conservation equation. There is an additional effect of the mineral matter in these cases that cannot be explained by heat sink alone. The disseminated mineral matter in the coal is therefore inhibiting the oxidation reaction due to physicochemical effects. 相似文献
997.
Speciation of the semivolatile hydrocarbon engine emissions from sunflower biodiesel 总被引:1,自引:0,他引:1
Biodiesel fuel is a very attractive alternative to conventional fuel and its effects in the engine performance and regulated emissions have been widely studied. However, the impact on unregulated individual compounds or chemical characteristics of exhaust emissions is not fully characterized. In this paper, the semivolatile fractions of the exhaust emissions of biodiesel blends and conventional fuel have been speciated. The results show great differences between the compounds emitted, especially regarding oxygenated and aromatic species. Likewise, there is a clear relationship between speciated hydrocarbons and other important emissions such as total hydrocarbons (HC), particulate matter (PM), volatile organic fraction (VOF) and mean particle diameter (Dm) of PM. 相似文献
998.
Chemical properties of coal which impact on gasification performance relate to those processes which do effect a change in chemical constitution, these in turn may lead to changes in physical properties such as particle size distribution and surface area of the coal. Turn-out samples obtained from a commercial-scale Sasol-Lurgi fixed-bed dry bottom (FBDB) gasifier were characterized to understand and interpret the internal chemical property behaviour and are discussed in relation to the residual C, H, N, S and O distribution profiles obtained. Thermodynamic equilibrium simulation of the organic and inorganic speciation behaviour occurring within a fixed-bed gasifier was modelled using the Fact-Sage simulation package, and used to support the measured ultimate analysis profile data obtained.The measured gasifier ultimate analysis profiles provided good insight into understanding the development of aromaticity of the char, expressed by the carbon:hydrogen ratio calculated on a mass basis. Equilibrium compositional profiles calculated for C, H, N, S and O provided discernment regarding the speciation and partitioning behaviour occurring within the fixed-bed-reactor. Fact-Sage thermodynamic equilibrium modeling of the gasifier related to the ultimate analysis results, was found to be useful in identifying an oxygen scavenging effect created by the mineral transformation behaviour occurring during reduction. It was found that oxygen-containing species such as Mg2Al4Si5O18 (corderite) and Fe2Al4Si5O18 (ferro-corderite) form within the reduction zone. It would appear that mineral composition is a more fundamental property than merely ash content in the gasification process, when viewed on an oxygen consumption basis. 相似文献
999.
Two processes, namely shrinkage and primary fragmentation are known to be the major causes of size reduction of wood during its devolatilization in a fluidized bed combustor. A simple phenomenological model incorporating these effects to compute the average char size at the end of devolatilization is proposed. Experiments are conducted in a bubbling fluidized bed combustor using wood having three different shapes namely, cylinder, cuboid and sphere, to measure the average char size at the end of devolatilization. The model prediction of average char size agrees with the measured values within a deviation of 15%. An experimental correlation is derived to determine the number of fragments and is used to estimate the mean char size. 相似文献
1000.
Organic‐acid‐catalyzed sol–gel route for preparing poly(methyl methacrylate)–silica hybrid materials
Jui‐Ming Yeh Kuan‐Yeh Huang Chung‐Feng Dai B. G. Chand Chang‐Jian Weng 《应用聚合物科学杂志》2008,110(4):2108-2114
In this study, a series of organic–inorganic hybrid sol–gel materials consisting of a poly(methyl methacrylate) (PMMA) matrix and dispersed silica (SiO2) particles were successfully prepared through an organic‐acid‐catalyzed sol–gel route with N‐methyl‐2‐pyrrolidone as the mixing solvent. The as‐synthesized PMMA–SiO2 nanocomposites were subsequently characterized with Fourier transform infrared spectroscopy and transmission electron microscopy. The solid phase of organic camphor sulfonic acid was employed to catalyze the hydrolysis and condensation (i.e., sol–gel reactions) of tetraethyl orthosilicate in the PMMA matrix. The formation of the hybrid membranes was beneficial for the physical properties at low SiO2 loadings, especially for enhanced mechanical strength and gas barrier properties, in comparison with the neat PMMA. The effects of material composition on the thermal stability, thermal conductivity, mechanical strength, molecular permeability, optical clarity, and surface morphology of the as‐prepared hybrid PMMA–SiO2 nanocomposites in the form of membranes were investigated with thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, gas permeability analysis, ultraviolet–visible transmission spectroscopy, and atomic force microscopy, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献