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51.
Counter-clustering for Training Pattern Selection 总被引:2,自引:0,他引:2
52.
Daniel Errandonea David Santamaria-Perez Tatiana Bondarenko 《Materials Research Bulletin》2010,45(11):1732-1735
We studied the high-pressure effects on the crystalline structure of monoclinic HfTiO4 and ZrTiO4. We found that the compressibility of these ceramics is highly non-isotropic, being the b-axis the most compressible one. In addition, the a-axis is found to have a small and negative compressibility. At 2.7 GPa (10.7 GPa) we discovered the onset of a structural phase transition in HfTiO4 (ZrTiO4), coexisting the low- and high-pressure phases in a broad pressure range. The new high-pressure phase has a monoclinic structure which involves an increase in the Ti-O coordination and a collapse of the cell volume. The equation of state for the low-pressure phase is also determined. 相似文献
53.
Electrochemical studies were carried out to estimate the risks of perchlorate formation in drinking water disinfected by direct electrolysis. Boron Doped Diamond (BDD) anodes were used in laboratory and commercially available cells at 20 °C. The current density was changed between 50 and 500 A m−2. For comparison, other anode materials such as platinum and mixed oxide were also tested. It was found that BDD anodes have a thousandfold higher perchlorate formation potential compared with the other electrode materials that were tested. In long-term discontinuous experiments all the chloride finally reacted to form perchlorate. The same result was obtained when probable oxychlorine intermediates (OCl−, ClO2−, ClO3−) were electrolysed in synthetic waters in the ppm range of concentrations. The tendency to form perchlorate was confirmed when the flow rate of drinking water was varied between 100 and 300 L h−1 and the temperature increased to 30 °C. In a continuous flow mode of operation a higher chloride concentration in the water resulted in a lower perchlorate formation. This can be explained by reaction competition of species near and on the anode surface for experiments both with synthetic and local drinking waters. It is concluded that the use of electrodes producing highly reactive species must be more carefully controlled in hygienically and environmentally oriented applications. 相似文献
54.
Kinetics and mechanism of low-temperature ozone decomposition by Co-ions adsorbed on silica 总被引:3,自引:0,他引:3
Tatiana L. Rakitskaya Alim A. Ennan Irina V. Granatyuk Alexander Yu. Bandurko Gilbert G. A. Balavoine Yurii V. Geletii V. Ya. Paina 《Catalysis Today》1999,53(4):616-723
Kinetics and mechanism of low-temperature ozone ((5–50) × 10−3 mol/m3 in the gas–air mixture) decomposition by Co-catalysts supported on silica have been studied. Co-ions adsorbed on silica react with surface oxygen species, thus resulting in an active catalyst. Low concentrations of Co-ions form a monolayer on the surface. Their specific catalytic activity remained constant, but sharply decreased at higher concentrations due to a formation of polynuclear Co-complexes. Ozone decomposition may occur either as a stoichiometric or catalytic process, depending on the ozone and catalyst concentrations. The turnover number increases with ozone concentration reaching a saturation point. It also increases with Co-concentration in the beginning, but drops at a concentration >1 × 10−4 mol/g. The mechanism of the reaction is discussed. 相似文献
55.
56.
Alejandro Vega Tatiana Baidyk Ernst Kussul José Luís Pérez Silva 《Optical Memory & Neural Networks》2011,20(3):168-180
Different types of neural networks can be used to classify images. We propose to apply LIRA (LImited Receptive Area) neural
classifier to work with images. To accelerate the neural network functioning we propose a digital implementation of the LIRA
neural classifier. We begin with a neuron design, and then continue with the neural network simulation. The advantage of neural
network is its parallel structure and possibility of the training. FPGA (Field Programmable Gate Array) allows the implementation
of these parallel algorithms in a single device. Speed of classification is one of the most important requirements in adaptive
control systems based on computer vision. The contribution of this article is LIRA neural classifier implementation with FPGA
for two classes to accelerate the training and recognition processes. 相似文献
57.
Physicochemical and functional properties of 2,2‐diallyl‐1,1,3,3‐tetraethylguanidinium chloride copolymers with N‐(n‐carboxyphenyl)maleimide, of N‐vinylpyrrolidone with N‐(n‐carboxyphenyl)maleimide, and of N‐vinylpyrrolidone with N‐phenylmaleimide have been investigated. Specific surface area and porosity of the copolymers under investigation have been determined by using the low‐temperature adsorption method. Electron microscope investigations in surfaces of the polymers have evinced that all of them have a spongy microstructure, the N‐vinylpyrrolidone copolymer with N‐(n‐carboxyphenyl)maleimide being the most homogeneous of these. Sorption capacity of the copolymers toward Re(VII) ions has been investigated. The process is described by the Langmuir isotherm. The pH is the most important parameter for sorption process of Re(VII). In the conjoint presence of Re(VII) and Mo(VI) in a solution of acid and ammoniac mediums, rhenium can be separated from molybdenum by using the sorbents under investigation at pH > 4.5 or at hydrochloric acid concentrations 0.1 mol L?1 and more. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
58.
Tatiana Koutchma 《Food and Bioprocess Technology》2009,2(2):138-155
A negative, public reaction is growing over the addition of chemical preservatives to liquid foods and beverages to extend
their shelf life and to protect against foodborne pathogens. As a physical method, ultraviolet light (UV) irradiation has
a positive consumer image and is of interest to the food industry as a low cost non-thermal method of preservation. Recent
advances in the science and engineering of UV light irradiation have demonstrated that this technology holds considerable
promise as an alternative to traditional thermal pasteurization for liquid foods and ingredients, fresh juices, soft drinks,
and beverages. However, its use for treating foods is still limited due to low UV transmittance of liquid foods. The goal
of this review is to provide a summary of the basic principles of UV light generation and propagation with emphasis on its
applications for liquid food processing. The review includes information on critical product and process factors that affect
UV light inactivation and consequently the delivery of a required scheduled process in liquids foods; measuring and modeling
of UV inactivation, and the important effects of UV light on overall quality and nutritional value of liquid foods. The commercially
available UV light sources and UV reactor designs that were used for liquid foods treatment are reviewed. The research priorities
and challenges that need to be addressed for the successful development of UV technology for liquid foods treatment are discussed. 相似文献
59.
60.
Tatiana Borisova Natalia Krisanova Nina Himmelreich 《Microgravity science and technology》2006,18(3-4):230-233
The present study evaluated the effect of artificial gravity loading on transporter-mediated uptake and release of L-glutamate using the inhibitors of glutamate transporters as tools. The competitive nontransportable, DL-threo-beta-benzyloxyaspartate (DL-TBOA), and transportable, DL-threo-beta-hydroxyaspartate (DL-THA), inhibitors were demonstrated to better inhibit the L-[14C]glutamate uptake under centrifuge-induced hypergravity compared with the normal gravity control. The effect of DL-TBOA on depolarization-induced carrier-mediated L-[14C]glutamate release also increased after hypergravity loading in Na+- and low [Na+] NMDG- supplemented media. 10 µM DL-TBOA-induced decrease in L-[14C]glutamate release in Na+ — supplemented medium was 15.2±2.2 % in the control experiments and 26.2±3.9 % after centrifuge-induced loading (P≤0,05) and in low [Na+] medium was 37.0±2.5 % and 45.0±3.4 %, respectively. 相似文献