WorldWideScience

Sample records for thermally oxidized soya

  1. Improving oxidative stability of soya and sunflower oil using ...

    African Journals Online (AJOL)

    Rosmarinus officinallis) and tert- butyl-hydroquinone (TBHQ) as possible antioxidants in sunflower and soya oil. Upon addition of 200 ppm of dried leaf extract, acetone extract yielded protection of the samples against oxidation more efficiently as ...

  2. Thermal expansion of beryllium oxide

    International Nuclear Information System (INIS)

    Solodukhin, A.V.; Kruzhalov, A.V.; Mazurenko, V.G.; Maslov, V.A.; Medvedev, V.A.; Polupanova, T.I.

    1987-01-01

    Precise measurements of temperature dependence of the coefficient of linear expansion in the 22-320 K temperature range on beryllium oxide monocrystals are conducted. A model of thermal expansion is suggested; the range of temperature dependence minimum of the coefficient of thermal expansion is well described within the frames of this model. The results of the experiment may be used for investigation of thermal stresses in crystals

  3. Watershed responses to Amazon soya bean cropland expansion and intensification.

    Science.gov (United States)

    Neill, Christopher; Coe, Michael T; Riskin, Shelby H; Krusche, Alex V; Elsenbeer, Helmut; Macedo, Marcia N; McHorney, Richard; Lefebvre, Paul; Davidson, Eric A; Scheffler, Raphael; Figueira, Adelaine Michela e Silva; Porder, Stephen; Deegan, Linda A

    2013-06-05

    The expansion and intensification of soya bean agriculture in southeastern Amazonia can alter watershed hydrology and biogeochemistry by changing the land cover, water balance and nutrient inputs. Several new insights on the responses of watershed hydrology and biogeochemistry to deforestation in Mato Grosso have emerged from recent intensive field campaigns in this region. Because of reduced evapotranspiration, total water export increases threefold to fourfold in soya bean watersheds compared with forest. However, the deep and highly permeable soils on the broad plateaus on which much of the soya bean cultivation has expanded buffer small soya bean watersheds against increased stormflows. Concentrations of nitrate and phosphate do not differ between forest or soya bean watersheds because fixation of phosphorus fertilizer by iron and aluminium oxides and anion exchange of nitrate in deep soils restrict nutrient movement. Despite resistance to biogeochemical change, streams in soya bean watersheds have higher temperatures caused by impoundments and reduction of bordering riparian forest. In larger rivers, increased water flow, current velocities and sediment flux following deforestation can reshape stream morphology, suggesting that cumulative impacts of deforestation in small watersheds will occur at larger scales.

  4. Thermal Oxidation of Structured Silicon Dioxide

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Jensen, Jørgen Arendt

    2014-01-01

    The topography of thermally oxidized, structured silicon dioxide is investigated through simulations, atomic force microscopy, and a proposed analytical model. A 357 nm thick oxide is structured by removing regions of the oxide in a masked etch with either reactive ion etching or hydrofluoric acid...

  5. Thermal oxidation for air toxics control

    International Nuclear Information System (INIS)

    Pennington, R.L.

    1991-01-01

    The Administration projects annual expenditures of $1.1 billion by 1995, increasing to $6.7 billion by 2005, in order to comply with the new Clean Air Act Title III hazardous air pollutant requirements. The Title III requirements include 189 hazardous air pollutants which must be reduced or eliminated by 2003. Twenty of the 189 listed pollutants account for approximately 75 percent of all hazardous air pollutant emissions. Ninety percent of these 20 pollutants can be effectively controlled through one or mote of the thermal oxidation technologies. This paper reports that the advantages and disadvantages of each thermal oxidation technology vary substantially and must be reviewed for each application in order to establish the most effective thermal oxidation solution. Effective thermal oxidation will meet MACT (maximum achievable control technology) emission standards

  6. Effects of soya oligosaccharides and soya oligopeptides on lipid metabolism in hyperlipidaemic rats.

    Science.gov (United States)

    Xie, Shali; Zhu, Jundong; Zhang, Yanqi; Shi, Kai; Shi, Yuangang; Ma, Xiao

    2012-08-01

    In the present study, we aimed to examine the effects of soya oligosaccharides (SOS) and soya oligopeptides (SOP) on blood lipid levels, release of vasoactive substances, antioxidant activity and faecal bile acid (FBA) excretion in rats fed a high-fat diet (HFD). Male Sprague-Dawley rats were evenly divided into five groups according to diets as follows: regular diet (control), HFD, HFD enriched with 2 % of SOS (SOS), HFD enriched with 3 % of SOP (SOP) and HFD enriched with 2 % SOS and 3 % SOP (SOSP). The results showed that SOS and SOP significantly reduced plasma total cholesterol, LDL-cholesterol and TAG, whereas HDL-cholesterol concentration was significantly increased. Furthermore, SOS and SOP reduced plasma apoB, apoE and the apoB:apoAI ratio, whereas apoAI was significantly increased. Moreover, SOS and SOP also reduced plasma thromboxane A₂ (TXA₂) and the TXA₂:prostacyclin (PGI₂) ratio, whereas plasma PGI₂ and nitric oxide were significantly increased. In addition, SOS and SOP significantly reduced serum and liver malondialdehyde concentrations and increased FBA excretion. However, we did not observe obvious influences of SOS and SOP on superoxide dismutase activities in the liver of HFD-fed rats. The combination of 2 % SOS and 3 % SOP showed a more marked effect than SOS or SOP alone in improving the lipid profile, release of vasoactive substances and increasing FBA excretion (P blood lipid levels, regulating vasoactive substances and protecting against oxidative stress.

  7. Non-thermal Plasma and Oxidative Stress

    Science.gov (United States)

    Toyokuni, Shinya

    2015-09-01

    Thermal plasmas and lasers have been used in medicine to cut and ablate tissues and for coagulation. Non-equilibrium atmospheric pressure plasma (NEAPP; non-thermal plasma) is a recently developed, non-thermal technique with possible biomedical applications. Although NEAPP reportedly generates reactive oxygen/nitrogen species, electrons, positive ions, and ultraviolet radiation, few research projects have been conducted to merge this technique with conventional free radical biology. Recently, Prof. Masaru Hori's group (Plasma Nanotechnology Research Center, Nagoya University) developed a NEAPP device with high electron density. Here electron spin resonance revealed hydroxyl radicals as a major product. To merge non-thermal plasma biology with the preexisting free radical biology, we evaluated lipid peroxidation and DNA modifications in various in vitro and ex vivo experiments. Conjugated dienes increased after exposure to linoleic and alfa-linolenic acids. An increase in 2-thiobarbituric acid-reactive substances was also increased after exposure to phosphatidylcholine, liposomes or liver homogenate. Direct exposure to rat liver in medium produced immunohistochemical evidence of 4-hydroxy-2-nonenal- and acrolein-modified proteins. Exposure to plasmid DNA induced dose-dependent single/double strand breaks and increased the amounts of 8-hydroxy-2'-deoxyguanosine and cyclobutane pyrimidine dimers. These results indicate that oxidative biomolecular damage by NEAPP is dose-dependent and thus can be controlled in a site-specific manner. Simultaneous oxidative and UV-specific DNA damage may be useful in cancer treatment. Other recent advancements in the related studies of non-thermal plasma in Nagoya University Graduate School of Medicine will also be discussed.

  8. Low temperature thermal oxidation of nitric oxide in polluted air

    Science.gov (United States)

    Lindqvist, Oliver; Ljungström, Evert; Svensson, Roger

    High concentrations of NO x (1500ppb) and high NO → NO2 conversion rates (100ppbh -1) have been measured in Göteborg during winter-time inversion periods. The conversion takes place without being significantly affected by light and the ozone concentration is always extremely low on these occasions. The dependence of the thermal oxidation 2 NO+ O2→ 2 NO2 on temperature, humidity and catalytic activity of different surfaces has been investigated in an extensive kinetic study. The reaction rate has a strong negative temperature dependence with apparent activation energies of -3.5 kj mole -1 for r.h. = 55 % and -7.3 kj mole -1for dry conditions. The reaction is surface catalysed and the experiments indicate that the thermal oxidation takes place in two steps, one rapid equilibrium reaction, forming intermediates such as N 2O 2 or NO 3, and one rate-determining step in which NO 2 is formed. The presence of an aerosol surface increased the reaction rate very slightly, while street surface material had a more significant influence. When the flow reactor walls were coated with salt-snow or road dirt mixtures to simulate the surface of a winter street, the reaction rate increased typically to 3.5 × 10 4M -2s -1 from 2.1 ×10 4M -2s -1 for a clean reactor at -2°C. These values should be compared with the generally accepted value for the reaction rate, which is 1.5 × 10 4M -2s -1 at 25°C. The experimental results allow conversion rates of ~100 NOppbh -1 at rush hours and ~ 40 NO ppb h -1 for normal or low traffic to be rationalized in terms of the thermal NO → NO2 reaction only, at an NO concentration of ~ 1000 ppb.

  9. Presence of genetically modified soya in products on the market

    OpenAIRE

    Spanish Agency for Consumer Affairs, Food Safety and Nutrition

    2014-01-01

    In recent years, the number of events of Genetically Modified Organisms (GMO) authorised in the European Union to be used as food or feed has notably increased, particularly in the case of genetically modified soya. The number has grown from September 2008, when t here was only one authorisation, Mons anto Company's Roundup Ready® soya, to seven different events currently authorised: 40- 3-2 soya, MON89788 soya, MON87701 soya, A2704-12 soya, A5547-127 soya,...

  10. Preparation and investigations of thermal properties of copper oxide ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 38; Issue 2. Preparation and investigations of thermal properties of copper oxide, aluminium oxide and graphite based on new organic phase change material for thermal energy storage. Murat Genc Betul Inci Zuhal Karagoz Genc Canan Aksu Canbay Memet Sekercı.

  11. Oxidation and thermal behavior of Jatropha curcas biodiesel ...

    African Journals Online (AJOL)

    The induction period of fresh Jatropha curcas biodiesel (JCB) is 3.27 hr. Also the thermal stability of JCB is very poor in terms of activation energy (Ea) and frequency factor (f). The thermal and oxidation behavior is also affected adversely by the container metal. The present paper is dealing with the study of oxidation and ...

  12. Synthesis and characterization of thermally oxidized ZnO films

    Indian Academy of Sciences (India)

    Administrator

    Abstract. Metallic zinc thin films were deposited onto glass substrates using vacuum thermal evaporation method. By thermal oxidation of as-deposited Zn films, in ambient conditions, at different temperatures (570,. 670 and 770 K, respectively, for 1 h) zinc oxide thin films were obtained. The structural characteristics of the.

  13. Danube Soya – Improving European GM-free soya supply for food and feed

    Directory of Open Access Journals (Sweden)

    Krön Matthias

    2015-09-01

    Full Text Available The Danube Soya Association is an international, voluntary, non-profit, non-governmental association promoting sustainable and GMO**-free soya production along the Danube River Basin – from Switzerland to the Black Sea. Founded in 2012 the association counts today more than 200 members from the whole value chain and civil society in 16 European countries. The members share the vision of a protein transition towards more European and more sustainable protein sources for food and feed. The Danube Area is an area of large potential agricultural surpluses and Danube Soya promotes the idea of using these surpluses to replace a part of the imported soya. The goals of the association are to increase value-added in the rural economies of Central Eastern Europe, promote European cooperation as well as a production of constant and sustainable local soya sources. The Danube Soya Association runs a certification scheme that reaches from soya seeds all the way to final products, which can be labelled with the consumer label “Fed with Danube Soya” (for animal products and “Danube Soya” (for soya food products. Together with its partners, the Danube Soya Association implements and supports dissemination and research projects on different topics.

  14. Synthesis of epoxidised soya bean oil acrylate

    International Nuclear Information System (INIS)

    Hussin bin Mohd Nor; Mohamad Hilmi bin Mahmood; Dahlan bin Haji Mohd.

    1988-10-01

    An epoxy acrylate was synthesized from Asahi's epoxy resin AER 331 which is an epoxidised soya bean oil (ESBO). Triethylamine (TEA) and Hydroquinone (HQ) were used as catalyst and inhibitor respectively. Observations of the experiment are described. (author)

  15. Thermal oxidation and electrical properties of silicon carbide metal-oxide-semiconductor structures

    Science.gov (United States)

    Singh, N.; Rys, A.

    1993-02-01

    The fabrication of metal-oxide-semiconductor (MOS) capacitors on n-type, Si-face 6H-SiC is described for both wet and dry oxidation processes, and the effect of thermal oxidation conditions on the electrical properties of MOS capacitors are investigated. The values of the oxide thickness were obtained as a function of the oxidation time at various oxidation temperatures (which were kept between 1150 and 1250 C). It was found that samples prepared by both dry and wet oxidation showed accumulation, depletion, and inversion regions under illumination, while inversion did not occur under dark conditions. The C-V characteristics of oxidized samples were improved after the oxidized samples were annealed in argon for 30 min. The relation between the oxide thickness and the oxidation time could be expressed by parabolic law, which is also used for thermal oxidation of Si.

  16. Radiation oxidation and subsequent thermal curing of polyacrylonitrile fiber

    International Nuclear Information System (INIS)

    Liu, Weihua; Wang, Mouhua; Xing, Zhe; Wu, Guozhong

    2014-01-01

    Polyacrylonitrile (PAN) fibers were exposed to gamma-ray irradiation at room temperature under vacuum, air and oxygen to investigate the radiation oxidation effects on PAN fibers. Radiation-induced oxidation degradation and crosslinking was evaluated by measuring the gel fraction. It was found that radiation oxidation took place mainly on the fiber surface due to the limited penetration of oxygen into PAN fibers from the surface, and the oxidation thickness increased with the oxygen pressure. Chain scission was dominant in the oxidized area, and crosslinking occurred in the inner part of the fibers. However, the oxidized regions of the fibers can be converted to gel via crosslinking by thermal curing at 160 °C in a N 2 atmosphere. Higher extents of radiation oxidation degradation led to a greater increase in the gel fraction. These results suggest that the radiation treatment of PAN fibers prior to thermal oxidation may be useful for manufacturing carbon fibers. - Highlights: • PAN fiber was irradiated in the presence of oxygen to induce oxidation at room temperature. • Oxidation degradation occurred at the fiber surface. • Oxidation thickness increased with oxygen pressure. • The oxidized region can be converted to a gel by the thermal treatment

  17. Electronic properties of thermally formed thin iron oxide films

    International Nuclear Information System (INIS)

    Wielant, J.; Goossens, V.; Hausbrand, R.; Terryn, H.

    2007-01-01

    The oxide layer, present between an organic coating and the substrate, guarantees adhesion of the coating and plays a determinating role in the delamination rate of the organic coating. The purpose of this study is to compare the resistive and semiconducting properties of thermal oxides formed on steel in two different atmospheres at 250 deg. C: an oxygen rich atmosphere, air, and an oxygen deficient atmosphere, N 2 . In N 2 , a magnetite layer grows while in air a duplex oxide film forms composed by an inner magnetite layer and a thin outer hematite scale. The heat treatment for different amounts of time at high temperature was used as method to sample the thickness variation and change in electronic and semiconducting properties of the thermal oxide layers. Firstly, linear voltammetric measurements were performed to have a first insight in the electrochemical behavior of the thermal oxides in a borate buffer solution. Electrochemical impedance spectroscopy in the same buffer combined with the Mott-Schottky analysis were used to determine the semiconducting properties of the thermal oxides. By spectroscopic ellipsometry (SE) and atomic force microscopy (AFM), respectively, the thickness and roughness of the oxide layers were determined supporting the physical interpretation of the voltammetric and EIS data. These measurements clearly showed that oxide layers with different constitution, oxide resistance, flatband potential and doping concentration can be grown by changing the atmosphere

  18. Bacteriological Contamination of Soya Bean Flour Sold in Makurdi ...

    African Journals Online (AJOL)

    Soya bean (Glycine max) is a leguminous crop that is used as a staple food worldwide. The raw harvest is processed into various food forms like soya bean flour and processing methods increase the chances of bacterial contamination. This research work assessed the bacteria contamination of soya bean flour sold in and ...

  19. Quality, safety, biofunctionality and fermentation control in soya

    NARCIS (Netherlands)

    Nout, M.J.R.

    2015-01-01

    Fermented soya foods play an important role in the diet and health of a large part of the world population. We will discuss the manufacture and properties of: soya sauce; semi-solid pastes such as miso, doujiang and doenjang; and solid fermented soya foods such as natto, kinema, tempe, sufu and

  20. Effects of fermented soya bean on digestion, absorption and diarrhoea

    NARCIS (Netherlands)

    Kiers, J.L.

    2001-01-01

    For many centuries Asian people have consumed soya beans in various forms of traditional fermented soya bean foods. Major desirable aspects of fermented soya bean foods are their attractive flavour and texture, certain nutritional properties, and possible health promoting effects. This

  1. Preparation and investigations of thermal properties of copper oxide ...

    Indian Academy of Sciences (India)

    Abstract. The effects of copper oxide, aluminium oxide and graphite on the thermal and structural properties of the organic phase change material (PCM) were investigated. Ethyl 2-(1H-benzotriazole-1-yl)acetate was selected as the pure PCM. Fourier transform infrared (FT-IR) spectroscopy, X-ray, energy dispersive X-ray ...

  2. The Role of Soya Oil Ester in Water-Based PCM for Low Temperature Cool Energy Storage

    Directory of Open Access Journals (Sweden)

    I. M. Rasta

    2016-01-01

    Full Text Available This study focuses on the preparation of the water-based phase change material (PCM with very small soya oil solution for low temperature latent heat thermal energy storage (LHTES. Soya oil ester is soluble very well in water and acts as nucleating agent for a novel solid-liquid PCM candidate that is suitable for low temperature cool storage in the range between −9°C and −6°C. Thermal energy storage properties of the water with very small soya oil ester solution were measured by T-history method. The experimental results show that very small amount of soya oil ester in water can lower the freezing point and trigger ice nucleation for elimination of the supercooling degree. The phase transition temperatures of the water-based PCMs with soya oil as nucleate agent were lower than those of individual water. The thermal properties make it potential PCM for LHTES systems used in low temperature cool energy storage applications.

  3. Thermal Properties of Oxides With Magnetoplumbite Structure for Advanced Thermal Barrier Coatings

    Science.gov (United States)

    Bansal, Narottam P.; Zhu, Dongming; Eslamloo-Grami, Maryam

    2007-01-01

    Oxides having magnetoplumbite structure are promising candidate materials for applications as high temperature thermal barrier coatings because of their high thermal stability, high thermal expansion, and low thermal conductivity. In this study, powders of LaMgAl11O19, GdMgAl11O19, SmMgAl11O19, and Gd0.7Yb0.3MgAl11O19 magnetoplumbite oxides were synthesized by citric acid sol-gel method and hot pressed into disk specimens. The thermal expansion coefficients (CTE) of these oxide materials were measured from room temperature to 1500 C. The average CTE value was found to be approx.9.6x10(exp -6)/C. Thermal conductivity of these magnetoplumbite-based oxide materials was also evaluated using steady-state laser heat flux test method. The effects of doping on thermal properties were also examined. Thermal conductivity of the doped Gd0.7Yb0.3MgAl11O19 composition was found to be lower than that of the undoped GdMgAl11O19. In contrast, thermal expansion coefficient was found to be independent of the oxide composition and appears to be controlled by the magnetoplumbite crystal structure. Thermal conductivity testing of LaMgAl11O19 and LaMnAl11O19 magnetoplumbite oxide coatings plasma sprayed on NiCrAlY/Rene N5 superalloy substrates indicated resistance of these coatings to sintering even at temperatures as high as 1600 C.

  4. ELISA for Detection of Soya Proteins in Meat Products

    Directory of Open Access Journals (Sweden)

    Eva Renčová

    2009-01-01

    Full Text Available Indirect competitive ELISA method for the detection of soya proteins in meat products was developed. The detection limit of the method is 0.5% of the weight of added soya protein. A total of 131 meat product samples such as salamis or sausages from the Czech Republic market were investigated for the presence of soya proteins. Soya proteins were detected in 84% of the investigated samples without any declaration on the package of the product. The use of vegetable additives, namely soya in meat products in the market of the Czech Republic is very frequent and the restriction of its usage by legislation relates only to some kinds of durable products and ham (Act 264/2003 Coll.. The need for sensitive inspecting methods for soya protein detection is not only associated with the economic aspect (adulteration, but mainly with consumer health protection in case of allergy to soya proteins.

  5. Danube Soya – Improving European GM-free soya supply for food and feed

    OpenAIRE

    Krön Matthias; Bittner Ursula

    2015-01-01

    The Danube Soya Association is an international, voluntary, non-profit, non-governmental association promoting sustainable and GMO**-free soya production along the Danube River Basin – from Switzerland to the Black Sea. Founded in 2012 the association counts today more than 200 members from the whole value chain and civil society in 16 European countries. The members share the vision of a protein transition towards more European...

  6. Effects of soya fatty acids on cassava ethanol fermentation.

    Science.gov (United States)

    Xiao, Dongguang; Wu, Shuai; Zhu, Xudong; Chen, Yefu; Guo, Xuewu

    2010-01-01

    Ethanol tolerance is a key trait of microbes in bioethanol production. Previous studies have shown that soya flour contributed to the increase of ethanol tolerance of yeast cells. In this paper, the mechanism of this ethanol tolerance improvement was investigated in cassava ethanol fermentation supplemented with soya flour or defatted soya flour, respectively. Experiment results showed that ethanol tolerance of cells from soya flour supplemented medium increased by 4-6% (v/v) than the control with defatted soya flour. Microscopic observation found that soya flour can retain the cell shape while dramatic elongations of cells were observed with the defatted soya flour supplemented medium. Unsaturated fatty acids (UFAs) compositions of cell membrane were analyzed and the UFAs amounts increased significantly in all tested strains grown in soya flour supplemented medium. Growth study also showed that soya flour stimulated the cell growth rate by approximately tenfolds at 72-h fermentation. All these results suggested that soya fatty acids play an important role to protect yeast cells from ethanol stress during fermentation process.

  7. Thermal instability of GaSb surface oxide

    Science.gov (United States)

    Tsunoda, K.; Matsukura, Y.; Suzuki, R.; Aoki, M.

    2016-05-01

    In the development of InAs/GaSb Type-II superlattice (T2SL) infrared photodetectors, the surface leakage current at the mesa sidewall must be suppressed. To achieve this requirement, both the surface treatment and the passivation layer are key technologies. As a starting point to design these processes, we investigated the GaSb oxide in terms of its growth and thermal stability. We found that the formation of GaSb oxide was very different from those of GaAs. Both Ga and Sb are oxidized at the surface of GaSb. In contrast, only Ga is oxidized and As is barely oxidized in the case of GaAs. Interestingly, the GaSb oxide can be formed even in DI water, which results in a very thick oxide film over 40 nm after 120 minutes. To examine the thermal stability, the GaSb native oxide was annealed in a vacuum and analyzed by XPS and Raman spectroscopy. These analyses suggest that SbOx in the GaSb native oxide will be reduced to metallic Sb above 300°C. To directly evaluate the effect of oxide instability on the device performance, a T2SL p-i-n photodetector was fabricated that has a cutoff wavelength of about 4 μm at 80 K. As a result, the surface leakage component was increased by the post annealing at 325°C. On the basis of these results, it is possible to speculate that a part of GaSb oxide on the sidewall surface will be reduced to metallic Sb, which acts as an origin of additional leakage current path.

  8. Bundled tungsten oxide nanowires under thermal processing

    International Nuclear Information System (INIS)

    Sun Shibin; Zhao Yimin; Xia Yongde; Zhu Yanqiu; Zou Zengda; Min Guanghui

    2008-01-01

    Ultra-thin W 18 O 49 nanowires were initially obtained by a simple solvothermal method using tungsten chloride and cyclohexanol as precursors. Thermal processing of the resulting bundled nanowires has been carried out in air in a tube furnace. The morphology and phase transformation behavior of the as-synthesized nanowires as a function of annealing temperature have been characterized by x-ray diffraction and electron microscopy. The nanostructured bundles underwent a series of morphological evolution with increased annealing temperature, becoming straighter, larger in diameter, and smaller in aspect ratio, eventually becoming irregular particles with size up to 5 μm. At 500 deg. C, the monoclinic W 18 O 49 was completely transformed to monoclinic WO 3 phase, which remains stable at high processing temperature. After thermal processing at 400 deg. C and 450 deg. C, the specific surface areas of the resulting nanowires dropped to 110 m 2 g -1 and 66 m 2 g -1 respectively, compared with that of 151 m 2 g -1 for the as-prepared sample. This study may shed light on the understanding of the geometrical and structural evolution occurring in nanowires whose working environment may involve severe temperature variations

  9. Thermally stimulated discharge conductivity study of zinc oxide ...

    Indian Academy of Sciences (India)

    Administrator

    The present work deals with transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermally stimulated discharge current (TSDC) study of inorganic metal oxide (ZnO) nanoparticles ... to be used in ultraviolet light-emitting diodes, photo- detectors, solar cells and surface ...

  10. Solid Waste Decontamination by Thermal Desorption and Catalytic Oxidation Methods

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Topka, Pavel; Soukup, Karel; Jirátová, Květa; Váňová, H.; Kaštánek, František

    2014-01-01

    Roč. 68, č. 9 (2014), s. 1279-1282 ISSN 0366-6352 R&D Projects: GA MPO FR-TI1/059 Institutional support: RVO:67985858 Keywords : thermal desorption * catalytic oxidation * soil decontamination Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.468, year: 2014

  11. Thermal Plasma Synthesis of Superparamagnetic Iron Oxide Nanoparticles

    NARCIS (Netherlands)

    Lei, P.Y.; Boies, A.M.; Calder, S.A.; Girshick, S.L.

    2012-01-01

    Superparamagnetic iron oxide nanoparticles were synthesized by injecting ferrocene vapor and oxygen into an argon/helium DC thermal plasma. Size distributions of particles in the reactor exhaust were measured online using an aerosol extraction probe interfaced to a scanning mobility particle sizer,

  12. Thermal oxidation vitrification flue gas elimination system

    International Nuclear Information System (INIS)

    Kephart, W.; Angelo, F.; Clemens, M.

    1995-01-01

    With minor modifications to a Best Demonstrated Available Technology hazardous waste incinerator, it is possible to obtain combustion without potentially toxic emissions by using technology currently employed in similar applications throughout industry. Further, these same modifications will reduce waste handling over an extended operating envelope while minimizing energy consumption. Three by-products are produced: industrial grade carbon dioxide, nitrogen, and a final waste form that will exceed Toxicity Characteristics Leaching Procedures requirements and satisfy nuclear waste product consistency tests. The proposed system utilizes oxygen rather than air as an oxidant to reduce the quantities of total emissions, improve the efficiency of the oxidation reactions, and minimize the generation of toxic NO x emissions. Not only will less potentially hazardous constituents be generated; all toxic substances can be contained and the primary emission, carbon dioxide -- the leading ''greenhouse gas'' contributing to global warming -- will be converted to an industrial by-product needed to enhance the extraction of energy feedstocks from maturing wells. Clearly, the proposed configuration conforms to the provisions for Most Achievable Control Technology as defined and mandated for the private sector by the Clear Air Act Amendments of 1990 to be implemented in 1997 and still lacking definition

  13. Tungsten Oxide Resistive Memory Using Rapid Thermal Oxidation of Tungsten Plugs

    Science.gov (United States)

    Lai, Erh-Kun; Chien, Wei-Chih; Chen, Yi-Chou; Hong, Tian-Jue; Lin, Yu-Yu; Chang, Kuo-Pin; Yao, Yeong-Der; Lin, Pang; Horng, Sheng-Fu; Gong, Jeng; Tsai, Shih-Chang; Lee, Ching-Hsiung; Hsieh, Sheng-Hui; Chen, Chun-Fu; Shih, Yen-Hao; Hsieh, Kuang-Yeu; Liu, Rich; Lu, Chih-Yuan

    2010-04-01

    A complementary metal oxide semiconductor (CMOS)-compatible WOx based resistive memory has been developed. The WOx memory layer is made from rapid thermal oxidation of W plugs. The device performs excellent electrical properties. The switching speed is extremely fast (˜2 ns) and the programming voltage (endurance. For multi-level cell (MLC) operation, it demonstrates 2-bit/cell storage with the endurance up to 10000 times. The rapid thermal oxidation (RTO) WOx resistance random access memory (RRAM) is very promising for both high-density and embedded memory applications.

  14. Thermal diffusivity and conductivity of thorium- uranium mixed oxides

    Science.gov (United States)

    Saoudi, M.; Staicu, D.; Mouris, J.; Bergeron, A.; Hamilton, H.; Naji, M.; Freis, D.; Cologna, M.

    2018-03-01

    Thorium-uranium oxide pellets with high densities were prepared at the Canadian Nuclear Laboratories (CNL) by co-milling, pressing, and sintering at 2023 K, with UO2 mass contents of 0, 1.5, 3, 8, 13, 30, 60 and 100%. At the Joint Research Centre, Karlsruhe (JRC-Karlsruhe), thorium-uranium oxide pellets were prepared using the spark plasma sintering (SPS) technique with 79 and 93 wt. % UO2. The thermal diffusivity of (Th1-xUx)O2 (0 ≤ x ≤ 1) was measured at CNL and at JRC-Karlsruhe using the laser flash technique. ThO2 and (Th,U)O2 with 1.5, 3, 8 and 13 wt. % UO2 were found to be semi-transparent to the infrared wavelength of the laser and were coated with graphite for the thermal diffusivity measurements. This semi-transparency decreased with the addition of UO2 and was lost at about 30 wt. % of UO2 in ThO2. The thermal conductivity was deduced using the measured density and literature data for the specific heat capacity. The thermal conductivity for ThO2 is significantly higher than for UO2. The thermal conductivity of (Th,U)O2 decreases rapidly with increasing UO2 content, and for UO2 contents of 60% and higher, the conductivity of the thorium-uranium oxide fuel is close to UO2. As the mass difference between the Th and U atoms is small, the thermal conductivity decrease is attributed to the phonon scattering enhanced by lattice strain due to the introduction of uranium in ThO2 lattice. The new results were compared to the data available in the literature and were evaluated using the classical phonon transport model for oxide systems.

  15. In situ thermally reduced graphene oxide/epoxy composites: thermal and mechanical properties

    Directory of Open Access Journals (Sweden)

    Ganiu B. Olowojoba

    2016-01-01

    Full Text Available Abstract Graphene has excellent mechanical, thermal, optical and electrical properties and this has made it a prime target for use as a filler material in the development of multifunctional polymeric composites. However, several challenges need to be overcome to take full advantage of the aforementioned properties of graphene. These include achieving good dispersion and interfacial properties between the graphene filler and the polymeric matrix. In the present work, we report the thermal and mechanical properties of reduced graphene oxide/epoxy composites prepared via a facile, scalable and commercially viable method. Electron micrographs of the composites demonstrate that the reduced graphene oxide (rGO is well dispersed throughout the composite. Although no improvements in glass transition temperature, tensile strength and thermal stability in air of the composites were observed, good improvements in thermal conductivity (about 36 %, tensile and storage moduli (more than 13 % were recorded with the addition of 2 wt% of rGO.

  16. Chemiluminescence from thermal oxidation of amino acids and proteins.

    Science.gov (United States)

    Millington, Keith R; Ishii, Hiroshi; Maurdev, George

    2010-05-01

    Chemiluminescence (CL) with maximum emission in the range 550-650 nm is observed when proteins and certain amino acids are heated in air, and CL intensity is significantly reduced in nitrogen. Of the 20 common amino acids, lysine (Lys) has the highest thermal CL intensity by a factor of approximately 30 over arginine, threonine and asparagine. This finding differs from previous studies on amino acids and proteins oxidised using free radical initiators or singlet oxygen, where tryptophan was the dominant factor for CL emission. CL from heating solid Lys in air is accompanied by browning and the generation of fluorescent products which are characteristic of advanced glycosylation end products (AGEs) in thermally treated milk proteins. During thermal oxidation, Lys may react with its own carbonyl oxidation products to form fluorescent compounds similar to AGEs via the formation of Schiff bases. The mechanism of thermal oxidation of proteins may be similar to polyamide polymers, where reaction of free primary amino groups with carbonyls to form Schiff bases plays a key role.

  17. Thermal gradient effects on the oxidation of Zircaloy fuel cladding

    International Nuclear Information System (INIS)

    Klein, A.C.; Reyes, J.N. Jr.; Maguire, M.A.

    1990-01-01

    A Thermal Gradient Test Facility (TGTF) has been designed and constructed to measure the thermal gradient effect on pressurized water reactor (PWR) fuel rod cladding. The TGTF includes a heat flux simulator assembly capable of producing a wide range of PWR operating conditions including water flow velocities and temperatures, water chemistry conditions, cladding temperatures, and heat fluxes ranging to 160 W/cm 2 . It is fully instrumented including a large number of thermocouples both inside the water flow channel and inside the cladding. Two test programs are in progress. First, cladding specimens are pre-oxidized in air at 500 deg. C and in 400 deg. C steam for various lengths of time to develop a range of uniform oxide thicknesses from 1 to 60 micrometers. The pre-oxidized specimens are placed in the TGTF to characterize the oxide thermal conductivity under a variety of water flow and heat flux conditions. Second, to overcome the long exposure times required under typical PWR conditions a series of tests with the addition of high concentrations of lithium hydroxide to the water are being considered. Static autoclave tests have been conducted with lithium hydroxide concentrations ranging from 0 to 2 moles per liter at 300, 330, and 360 deg. C for up to 36 hours. Results for zircaloy-4 show a considerable increase in the weight gain for the exposed samples with oxidation rate enhancement factors as high as 70 times that of pure water. Operation of the TGTF with elevated lithium hydroxide levels will yield real-time information concerning the effects of a heat flux on the oxidation kinetics of zircaloy fuel rod cladding. (author). 5 refs, 5 figs, 2 tabs

  18. Thermal neutron detectors based on complex oxide crystals

    CERN Document Server

    Ryzhikov, V; Volkov, V; Chernikov, V; Zelenskaya, O

    2002-01-01

    The ways of improvement of spectrometric quality of CWO and GSO crystals have been investigated with the aim of their application in thermal neutron detectors based on radiation capture reactions. The efficiency of the neutron detection by these crystals was measured, and the obtained data were compared with the results for sup 6 LiI(Tl) crystals. It is shown that the use of complex oxide crystals and neutron-absorption filters for spectrometry of thermal and resonance neutrons could be a promising method in combination with computer data processing. Numerical calculations are reported for spectra of gamma-quanta due to radiation capture of the neutrons. To compensate for the gamma-background lines, we used a crystal pair of heavy complex oxides with different sensitivity to neutrons.

  19. Studies of physicochemical properties of graphite oxide and thermally exfoliated/reduced graphene oxide

    Directory of Open Access Journals (Sweden)

    Drewniak Sabina Elżbieta

    2015-12-01

    Full Text Available The aim of the experimental research studies was to determine some electrical properties of graphite oxide and thermally exfoliated/reduced graphene oxide. The authors tried to interpret the obtained physicochemical results. For that purpose, both resistance measurements and investigation studies were carried out in order to characterize the samples. The resistance was measured at various temperatures in the course of composition changes of gas atmospheres (which surround the samples. The studies were also supported by such methods as: scanning electron microscopy (SEM, Raman spectroscopy (RS, atomic force microscopy (AFM and thermogravimetry (TG. Moreover, during the experiments also the elemental analyses (EA of the tested samples (graphite oxide and thermally exfoliated/reduced graphene oxide were performed.

  20. Volumetric and viscometric behaviour of soya bean and gram ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... properties. Thus an estimation of intermolecular forces with water and proteins in aqueous solution is of interest to protein engineering (Mulder et al., 1839; Leiberg et al.,. 1841). Soya protein has cholesterol lowering effect in human serum (Carroll et al., 1995, 1980) with lysine and arginine rich soya protein ...

  1. Effect of soya bean diet preparations on some haematological and ...

    African Journals Online (AJOL)

    Effects of Soya bean diet preparations on the hematocrit, hemoglobin concentration, total plasma protein, plasma albumin, sodium, potassium and chloride concentrations were studied in male albino rats. The animals were fed diets containing 75%, 50% and 25% Soya bean in groups II, III and IV respectively. Group I rats ...

  2. Volumetric and viscometric behaviour of soya bean and gram ...

    African Journals Online (AJOL)

    Volumetric and viscometric behaviour of soya bean and gram proteins in aqueous methotrexate (anticancer drug) solution at 298.15 to 308.15K. ... and viscosities (h) for 0.00005 to 0.0004 kg.mol-1 (50 to 400 mmol kg-1) aqueous methotrexate (MTX), gram (Gp) and soya bean (SBp) proteins, and similar compositions of Gp

  3. Utilization of soya protein as an alternative protein source in ...

    African Journals Online (AJOL)

    The effect of replacing fish protein with soya protein in tilapia (Oreochromis niloticus) diets was examined. Three isoproteic (35%) diets containing 0% (FD); 50% (MD) and 100% (SD) fish protein substituted by soya protein were formulated. Fish (initial weight = 11.56 ± 4.22 g) was fed with experimental diets for 180 days.

  4. Soya ve Soya Ürünlerinin Fonksiyonel Gıda Bileşenleri

    Directory of Open Access Journals (Sweden)

    Dilara Nilüfer

    2015-02-01

    Full Text Available Soya ürünleri, yüksek miktarda soya proteini, izoflavonlar, omega–3-yağ asitleri ve diyet lifi içerikleri ile çok önemli fonksiyonel gıda bileşenleri veya ürünleridir. Sağlığa olumlu etkilerinden dolayı, ürün geliştirmede soyanın geleneksel gıdalara tamamen veya kısmen ilave edilmesi veya diğer bileşenlerle yer değiştirmesi yönünde eğilimler giderek artış göstermektedir. Soyanın sağlığa yararlı etkileri tüketicilere yaygın olarak tüketilen ve kabul edilebilir nitelikteki soya ürünleri ile ulaştırılabilir. Çok çeşitli soya esaslı bileşen dünya pazarında mevcut olup, formülasyonların optimizasyonu için her birinin fonksiyonu, besin değeri, maliyet ve lezzet özellikleri tam olarak anlaşılmalıdır. Bu çalışmada; soya ürünlerinin fonksiyonel gıda bileşenlerinin sağlığa olan etkileri, gıda süreçlerinden etkilenmeleri ve ürünlerde uygulamalarının irdelenmesi amaçlanmıştır.

  5. Effect of fermented soya beans on diarrhoea and feed efficiency in weaned piglets

    NARCIS (Netherlands)

    Kiers, J.L.; Meijer, J.C.; Nout, M.J.R.; Rombouts, F.M.; Nabuurs, M.J.A.; Meulen, van der J.

    2003-01-01

    Aims: To evaluate anti-diarrhoeal and growth enhancing properties of fermented soya beans in weaned piglets. Methods and Results: In a first phase piglet diet, toasted full-fat soya beans (20%) were replaced with either cooked soya beans or Rhizopus microsporus or Bacillus subtilis fermented soya

  6. Negative Thermal Expansion and Ferroelectric Oxides in Electronic Device Composites

    Science.gov (United States)

    Trujillo, Joy Elizabeth

    Electronic devices increasingly pervade our daily lives, driving the need to develop components which have material properties that can be designed to target a specific need. The principle motive of this thesis is to investigate the effects of particle size and composition on three oxides which possess electronic and thermal properties essential to designing improved ceramic composites for more efficient, high energy storage devices. A metal matrix composite project used the negative thermal expansion oxide, ZrW2O 8, to offset the high thermal expansion of the metal matrix without sacrificing high thermal conductivity. Composite preparation employed a powder mixing technique to achieve easy composition control and homogenous phase distribution in order to build composites which target a specific coefficient of thermal expansion (CTE). A tailorable CTE material is desirable for overcoming thermomechanical failure in heat sinks or device casings. This thesis also considers the particle size effect on dielectric properties in a common ferroelectric perovskite, Ba1-xSrxTiO 3. By varying the Ba:Sr ratio, the Curie temperature can be adjusted and by reducing the particle size, the dielectric constant can be increased and hysteresis decreased. These conditions could yield anonymously large dielectric constants near room temperature. However, the ferroelectric behavior has been observed to cease below a minimum size of a few tens of nanometers in bulk or thin film materials. Using a new particle slurry approach, electrochemical impedance spectroscopy allows dielectric properties to be determined for nanoparticles, as opposed to conventional methods which measure only bulk or thin film dielectric properties. In this manner, Ba1-xSrxTiO3 was investigated in a new size regime, extending the theory on the ferroelectric behavior to film heterostructures of STO/YSZ are used in electrochemical energy devices due to their enhanced interfacial ionic conductivity. This work

  7. [Soya isoflavones and evidences on cardiovascular protection].

    Science.gov (United States)

    González Cañete, Natalia; Durán Agüero, Samuel

    2014-06-01

    Soya isoflavones represent a group of non-nutritive, bioactive compounds, of non-steroidal phenolic nature that are present in soy bean and derived foods. They share with other compounds the capacity of binding to estrogenic receptors from different cells and tissues so that they may act as phytoestrogens. The current interest in these compounds comes from the knowledge that in Asian populations with high levels of their consumption the prevalence of cancer and cardiovascular disease is lower, as compared to the Western countries populations. This cardiovascular benefit would be the result not only of the modulation of plasma lipids, which is a widely studied mechanism. This paper reviews the published evidence about the beneficial effects of soya isoflavones and the different mechanisms of action that would benefit cardiovascular health and that surpass the mechanisms traditionally approached such as the modulation of plasma lipids, and that implicate the regulation of cellular and enzymatic functions in situations such as inflammation, thrombosis, and atherosclerotic progression. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  8. Applications and properties of thermally sprayed oxide ceramics

    International Nuclear Information System (INIS)

    Pawlowski, L.

    1991-01-01

    After a brief discussion of the general properties of thermally sprayed oxide ceramics, some of the more important materials are discussed in detail. The electric properties of Al 2 O 3 , such as electric resistivity, dielectric constant and dielectric strength, are shown together with the applications of thermally sprayed alumina coatings in 'corona rolls' and substrates in hybrid microelectronics. The thermal conductivity of ZrO 2 stabilized with a different Y 2 O 3 content is discussed together with the coatings' microstructure. The research on the development of zirconia coatings for application in the advanced turbines is briefly described. The mechanical properties of thermally sprayed Cr 2 O 3 coatings as well as their microstructure are shown. As chromia coatings often contain suboxides or even metallic chromium, a special powder giving metal free deposits has been developed and the coatings sprayed therefrom are applied in the printing industry as 'anilox rolls'. Finally, microstructure and some electrical properties of a high temperature superconductor YBa 2 CU 3 O 7-x are presented. (orig.) [de

  9. Morphology and the physical and thermal properties of thermoplastic polyurethane reinforced with thermally reduced graphene oxide

    Directory of Open Access Journals (Sweden)

    Strankowski Michał

    2015-12-01

    Full Text Available In this study, thermally reduced graphene oxide (TRG-containing polyurethane nanocomposites were obtained by the extrusion method. The content of TRG incorporated into polyurethane elastomer systems equaled 0.5, 1.0, 2.0 and 3.0 wt%. The morphology, static and dynamic mechanical properties, and thermal stability of the modified materials were investigated. The application of TRG resulted in a visible increase in material stiffness as confirmed by the measurements of complex compression modulus (E′ and glass transition temperature (Tg. The Tg increased with increasing content of nanofiller in the thermoplastic system. The addition of thermally reduced graphene oxide had a slight effect on thermal stability of the obtained materials. The incorporation of 0.5, 1.0, 2.0 and 3.0 wt% of TRG into a system resulted in increased char residues compared to unmodified PU elastomer. Also, this study demonstrated that after exceeding a specific amount of TRG, the physicomechanical properties of modified materials start to deteriorate.

  10. Zero and low coefficient of thermal expansion polycrystalline oxides

    International Nuclear Information System (INIS)

    Skaggs, S.R.

    1977-09-01

    Polycrystalline oxide systems with zero to low coefficient of thermal expansion (CTE) investigated by the author include hafnia-titania and hafnia. The CTE for 30 to 40 mol% TiO 2 in HfO 2 is less than or equal to 1 x 10 -6 / 0 C, while for other compositions in the range 25 to 60 mol% it is approximately 4 x 10 -6 / 0 C. An investigation of the CTE of 99.999% HfO 2 yielded a value of 4.6 x 10 -6 / 0 C from room temperature to 1000 0 C. Correlation with data on HfO 2 by other investigators shows a definite relationship between the CTE and the amount of ZrO 2 present. Data are listed for comparison of the CTE of several other polycrystalline oxides investigated by Holcombe at Oak Ridge

  11. Zero and low coefficient of thermal expansion polycrystalline oxides

    International Nuclear Information System (INIS)

    Skaggs, S.R.

    1977-01-01

    Polycrystalline oxide systems with zero to low coefficient of thermal expansion (CTE) investigated by the author include hafnia-titania and hafnia. The CTE for 30 to 40 mol percent TiO 2 in HfO 2 is less than or equal to 1 x 10 -6 / 0 C, while for other compositions in the range 25 to 60 mol percent approximately 4 x 10 -6 / 0 C. An investigation of the CTE of 99.999 percent HfO 2 yielded a value of 4.6 x 10 -6 / 0 C from room temperature to 1000 0 C. Correlation with data on HfO 2 by other investigators shows a definite relationship between the CTE and the amount of ZrO 2 present. Data are listed for comparison of the CTE of several other polycrystalline oxides investigated by Holcombe at Oak Ridge

  12. Inflammatory markers in a randomised soya intervention among men.

    Science.gov (United States)

    Maskarinec, Gertraud; Oum, Robert; Chaptman, Ann K; Ognjanovic, Simona

    2009-06-01

    The present analysis investigated the effect of soya foods on serum levels of six inflammatory markers, leptin, adiponectin, monocyte attractant protein 1 (MCP-1), macrophage inflammatory protein-1b (MIP-1b), IL-6 and C-reactive protein (CRP), and their relationship with BMI and lifetime soya intake. We randomised twenty-four men to a high- (two daily servings with 30-35 mg isoflavones per serving) or a low-soya diet for 3 months. After a 1-month washout period, the men crossed over to the other treatment. We used a multiplex bead immunoassay to measure leptin, adiponectin, MCP-1 and MIP-1b and ELISA assays for IL-6 and CRP. The statistical analysis applied mixed models that incorporated the four repeated measurements. The men had a mean age of 58.7 (sd 7.2) years and a mean BMI of 28.4 (sd 4.9) kg/m2. We observed no significant intervention effect of the soya treatment on any of the six markers. After adjustment for age and ethnicity, highly significant associations of BMI and body weight with leptin and MCP-1 emerged. Men with high soya intake early in life also had higher levels of leptin and MCP-1, whereas no association was seen for soya intake during adulthood. MIP-1b, adiponectin, IL-6 and CRP were not related to BMI, body weight or soya intake at any time in life. No intervention effect of soya foods on markers of inflammation was observed in this small study, but adiposity and early-life soya intake were related to higher leptin and MCP-1 levels.

  13. Structure-property studies of thermoplastic and thermosetting polyurethanes using palm and soya oils-based polyols.

    Science.gov (United States)

    Mohammed, Issam Ahmed; Al-Mulla, Emad Abbas Jaffar; Kadar, Nurul Khizien Abdul; Ibrahim, Mazlan

    2013-01-01

    Palm and soya oils were converted to monoglycerides via transesterification of triglycerides with glycerol by one step process to produce renewable polyols. Thermoplastic polyurethanes (TPPUs) were prepared from the reaction of the monoglycerides which act as polyol with 4,4'-methylenediphenyldiisocyanate (MDI) whereas, thermosetting polyurethanes (TSPUs) were prepared from the reaction of glycerol, MDI and monoglycerides in one pot. Characterization of the polyurethanes was carried out by FT-IR, (1)H NMR, and iodine value and sol-gel fraction. The TSPUs showed good thermal properties compared to TPPUs as well as TSPUs exhibits good properties in pencil hardness and adhesion, however poorer in flexural and impact strength compared to TPPUs. The higher percentage of cross linked fraction, the higher degree of cross linking occurred, which is due to the higher number of double bond presents in the TSPUs. These were reflected in iodine value test as the highest iodine value of the soya-based thermosetting polyurethanes confirmed the highest degree of cross linking. Polyurethanes based on soya oil showed better properties compared to palm oil. This study is a breakthrough development of polyurethane resins using palm and soya oils as one of the raw materials.

  14. Modeling of thermal expansion coefficient of perovskite oxide for solid oxide fuel cell cathode

    Science.gov (United States)

    Heydari, F.; Maghsoudipour, A.; Alizadeh, M.; Khakpour, Z.; Javaheri, M.

    2015-09-01

    Artificial intelligence models have the capacity to eliminate the need for expensive experimental investigation in various areas of manufacturing processes, including the material science. This study investigates the applicability of adaptive neuro-fuzzy inference system (ANFIS) approach for modeling the performance parameters of thermal expansion coefficient (TEC) of perovskite oxide for solid oxide fuel cell cathode. Oxides (Ln = La, Nd, Sm and M = Fe, Ni, Mn) have been prepared and characterized to study the influence of the different cations on TEC. Experimental results have shown TEC decreases favorably with substitution of Nd3+ and Mn3+ ions in the lattice. Structural parameters of compounds have been determined by X-ray diffraction, and field emission scanning electron microscopy has been used for the morphological study. Comparison results indicated that the ANFIS technique could be employed successfully in modeling thermal expansion coefficient of perovskite oxide for solid oxide fuel cell cathode, and considerable savings in terms of cost and time could be obtained by using ANFIS technique.

  15. Effects of pressure on thermal transport in plutonium oxide powder

    International Nuclear Information System (INIS)

    Bielenberg, Patricia; Prenger, F. Coyne; Veirs, Douglas Kirk; Jones, Jerry

    2004-01-01

    Radial temperature profiles in plutonium oxide (PuO 2 ) powder were measured in a cylindrical vessel over a pressure range of 0.055 to 334.4 kPa with two different fill gases, helium and argon. The fine PuO 2 powder provides a very uniform self-heating medium amenable to relatively simple mathematical descriptions. At low pressures ( 2 powder has small particle sizes (on the order of 1 to 10 μm), random particle shapes, and high porosity so a more general model was required for this system. The model correctly predicts the temperature profiles of the powder over the wide pressure range for both argon and helium as fill gases. The effective thermal conductivity of the powder bed exhibits a pressure dependence at higher pressures because the pore sizes in the interparticle contact area are relatively small (less than 1 μm) and the Knudsen number remains above the continuum limit at these conditions for both fill gases. Also, the effective thermal conductivity with argon as a fill gas is higher than expected at higher pressures because the solid pathways account for over 80% of the effective powder conductivity. The results obtained from this model help to bring insight to the thermal conductivity of very fine ceramic powders with different fill gases.

  16. Growth and thermal oxidation of Ru and ZrO2 thin films as oxidation protective layers

    NARCIS (Netherlands)

    Coloma Ribera, R.

    2017-01-01

    This thesis focuses on the study of physical and chemical processes occurring during growth and thermal oxidation of Ru and ZrO2 thin films. Acting as oxidation resistant capping materials to prevent oxidation of layers underneath, these films have several applications, i.e., in microelectronics

  17. Packaging material and flexible medical tubing containing thermally exfoliated graphite oxide

    Science.gov (United States)

    Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

    2011-01-01

    A packaging material or flexible medical tubing containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.

  18. Thermal neutron scattering cross sections of beryllium and magnesium oxides

    International Nuclear Information System (INIS)

    Al-Qasir, Iyad; Jisrawi, Najeh; Gillette, Victor; Qteish, Abdallah

    2016-01-01

    Highlights: • Neutron thermalization in BeO and MgO was studied using Ab initio lattice dynamics. • The BeO phonon density of states used to generate the current ENDF library has issues. • The BeO cross sections can provide a more accurate ENDF library than the current one. • For MgO an ENDF library is lacking: a new accurate one can be built from our results. • BeO is a better filter than MgO, especially when cooled down to 77 K. - Abstract: Alkaline-earth beryllium and magnesium oxides are fundamental materials in nuclear industry and thermal neutron scattering applications. The calculation of the thermal neutron scattering cross sections requires a detailed knowledge of the lattice dynamics of the scattering medium. The vibrational properties of BeO and MgO are studied using first-principles calculations within the frame work of the density functional perturbation theory. Excellent agreement between the calculated phonon dispersion relations and the experimental data have been obtained. The phonon densities of states are utilized to calculate the scattering laws using the incoherent approximation. For BeO, there are concerns about the accuracy of the phonon density of states used to generate the current ENDF/B-VII.1 libraries. These concerns are identified, and their influences on the scattering law and inelastic scattering cross section are analyzed. For MgO, no up to date thermal neutron scattering cross section ENDF library is available, and our results represent a potential one for use in different applications. Moreover, the BeO and MgO efficiencies as neutron filters at different temperatures are investigated. BeO is found to be a better filter than MgO, especially when cooled down, and cooling MgO below 77 K does not significantly improve the filter’s efficiency.

  19. Preparation and characterization of soaps made from soya bean oil ...

    African Journals Online (AJOL)

    This research work deals with the preparation of soaps from neem oil and soya bean oil blends and analyses the soap produced. The soaps were produced using cold process technique by varying the percentage of oils; (soya bean oil and neem oil) in the ratio of 100%, 90/10%, 80/20%, 70/30%, 60/40%, 50/50%, 40/60%, ...

  20. Quantifying Dustiness, Specific Allergens, and Endotoxin in Bulk Soya Imports

    Directory of Open Access Journals (Sweden)

    Howard J. Mason

    2017-11-01

    Full Text Available Soya is an important bulk agricultural product often transported by sea as chipped beans and/or the bean husks after pelletisation. There are proven allergens in both forms. Bulk handling of soya imports can generate air pollution containing dust, allergens, and pyrogens, posing health risks to dockside workers and surrounding populations. Using an International Organization for Standardization (ISO standardised rotating drum dustiness test in seven imported soya bulks, we compared the generated levels of dust and two major soya allergens in three particle sizes related to respiratory health. Extractable levels of allergen and endotoxin from the bulks showed 30–60 fold differences, with levels of one allergen (hydrophobic seed protein and endotoxin higher in husk. The generated levels of dust and allergens in the three particle sizes also showed very wide variations between bulks, with aerolysed levels of allergen influenced by both the inherent dustiness and the extractable allergen in each bulk. Percentage allergen aerolysed from pelletized husk—often assumed to be of low dustiness—after transportation was not lower than that from chipped beans. Thus, not all soya bulks pose the same inhalation health risk and reinforces the importance of controlling dust generation from handling all soya bulk to as low as reasonably practicable.

  1. Oxidation kinetics of Si and SiGe by dry rapid thermal oxidation, in-situ steam generation oxidation and dry furnace oxidation

    Science.gov (United States)

    Rozé, Fabien; Gourhant, Olivier; Blanquet, Elisabeth; Bertin, François; Juhel, Marc; Abbate, Francesco; Pribat, Clément; Duru, Romain

    2017-06-01

    The fabrication of ultrathin compressively strained SiGe-On-Insulator layers by the condensation technique is likely a key milestone towards low-power and high performances FD-SOI logic devices. However, the SiGe condensation technique still requires challenges to be solved for an optimized use in an industrial environment. SiGe oxidation kinetics, upon which the condensation technique is founded, has still not reached a consensus in spite of various studies which gave insights into the matter. This paper aims to bridge the gaps between these studies by covering various oxidation processes relevant to today's technological needs with a new and quantitative analysis methodology. We thus address oxidation kinetics of SiGe with three Ge concentrations (0%, 10%, and 30%) by means of dry rapid thermal oxidation, in-situ steam generation oxidation, and dry furnace oxidation. Oxide thicknesses in the 50 Å to 150 Å range grown with oxidation temperatures between 850 and 1100 °C were targeted. The present work shows first that for all investigated processes, oxidation follows a parabolic regime even for thin oxides, which indicates a diffusion-limited oxidation regime. We also observe that, for all investigated processes, the SiGe oxidation rate is systematically higher than that of Si. The amplitude of the variation of oxidation kinetics of SiGe with respect to Si is found to be strongly dependent on the process type. Second, a new quantitative analysis methodology of oxidation kinetics is introduced. This methodology allows us to highlight the dependence of oxidation kinetics on the Ge concentration at the oxidation interface, which is modulated by the pile-up mechanism. Our results show that the oxidation rate increases with the Ge concentration at the oxidation interface.

  2. Antioxidant Effect of Pollen Grains and Soya Lecithin on Cadmium-induced Biochemical and Structural disorders in the Ovary of Female Rats during Estrus Cycle

    International Nuclear Information System (INIS)

    Mansour, S. Z.; Ramadan, F. L.

    2010-01-01

    This work aims at assessing the role of pollen grains with soya lecithin on cadmium-induced damage. Cadmium chloride was administered to female albino rats (0.5 mg/kg b. wt, i.p.) during 6 weeks. Pollen grains (54 mg/kg b.wt), and soya lecithin (18 mg/kg b.wt), were given, via gavages, 7 days before cadmium administration, and during cadmium treatment. The results demonstrate that cadmium exposure induces different distortions in ovarian tissues, fibrotic follicular cortex, appearance of atretic follicles, partial oocytes degeneration and significant decreases in the number of primordial, primary, secondary and antral follicles associated with significant increase in MDA levels , significant decreases in GSH content, GSH-Px, SOD and Cat activities. Significant increases in total saturated and monounsaturated fatty acids and significant decreases in polyunsaturated fatty acids levels were recorded. Significant decreases in plasma calcium, progesterone, estradiol and HDL-C and significant increases in triglycerides, total cholesterol, LDL-C levels were recorded. Administration of pollen grains with soya lecithin has significantly improved the antioxidant status and fatty acids levels associated with regeneration of ovarian tissues. Significant amelioration in saturated and unsaturated fatty acids, and hormones levels were also recorded. It is concluded that pollen grains with soya lecithin may protect the ovary during estrus cycle from cadmium-induced toxicity. Key words: pollen, soya lecithin, cadmium, oxidative stress, ovary, fatty acids, follicle numbers

  3. Participation of Taxifolin in the Protection of Soya Seeds from the Effects of Heavy Metal Salts

    Directory of Open Access Journals (Sweden)

    V.A. Kuznetsova

    2015-06-01

    Full Text Available A correlation was revealed between the specific activity of peroxidases and their multiple forms during the germination of soya seeds (Glycine max (L. Merrill in the presence of heavy metal salts. It was shown that lead and cadmium sulfates cause emergence of new forms of the enzyme with high electrophoretic mobility, which indicates that the identified enzyme forms are involved in the molecular mechanism of adaptation to oxidative stress. Addition of taxifolin (dihydroquercetin, a bioflavonoid antioxidant, to the salts of heavy metals caused decrease in the specific activity of peroxidases and favored emergence of new forms of the enzyme, which were absent in the control samples.

  4. High sensitivity of positron annihilation to thermal oxidation of polyethylene

    Science.gov (United States)

    Ito, Kenji; Kobayashi, Yoshinori; Nanasawa, Atsushi

    2003-01-01

    We demonstrate the high sensitivity of positron annihilation to compositional changes related to the thermal degradation of polyethylene (PE). Positron annihilation γ-ray and lifetime measurements were conducted for PE films with and without antioxidant (1000-ppm Ciba® IRGANOX® 1076), subjected to heat treatment at 100 °C for different periods, to a maximum of 30 days. For the film without antioxidant, the positron Doppler parameter (S) and ortho-positronium formation probability (Io-Ps) appreciably decreased with increased heat treatment times, whereas they barely changed for the film with antioxidant. This, together with the Fourier transform infrared measurements, demonstrated that the variations of S and Io-Ps are caused by the thermal oxidation of PE. The S parameter was found to be sensitive to the early stage of degradation, where the carbonyl concentration is inferred to be lower than 100 ppm. The high sensitivity results from the large positron mobility in PE and from the high positron affinity of oxygen-containing polar groups. This work provides the basis for an application of positron annihilation to sensitive detection of the initial degradation of PE and other nonpolar polymers.

  5. Thermal stress analysis of sulfur deactivated solid oxide fuel cells

    Science.gov (United States)

    Zeng, Shumao; Parbey, Joseph; Yu, Guangsen; Xu, Min; Li, Tingshuai; Andersson, Martin

    2018-03-01

    Hydrogen sulfide in fuels can deactivate catalyst for solid oxide fuel cells, which has become one of the most critical challenges to stability. The reactions between sulfur and catalyst will cause phase changes, leading to increase in cell polarization and mechanical mismatch. A three-dimensional computational fluid dynamics (CFD) approach based on the finite element method (FEM) is thus used to investigate the polarization, temperature and thermal stress in a sulfur deactivated SOFC by coupling equations for gas-phase species, heat, momentum, ion and electron transport. The results indicate that sulfur in fuels can strongly affect the cell polarization and thermal stresses, which shows a sharp decrease in the vicinity of electrolyte when 10% nickel in the functional layer is poisoned, but they remain almost unchanged even when the poisoned Ni content was increased to 90%. This investigation is helpful to deeply understand the sulfur poisoning effects and also benefit the material design and optimization of electrode structure to enhance cell performance and lifetimes in various hydrocarbon fuels containing impurities.

  6. Thermal and radiation induced polymerisation of carbon sub-oxide

    International Nuclear Information System (INIS)

    Schmidt, Michel

    1964-03-01

    This research thesis addresses the study of the polymerisation of carbon sub-oxide (C 3 O 2 ) in gaseous phase. As this work is related to other researches dealing with the reactions of the graphite-CO 2 system which occur in graphite-moderated nuclear reactors, a first intention was to study the behaviour of C 3 O 2 when submitted to radiations. Preliminary tests showed that the most remarkable result of this action was the formation of a polymer. It was also noticed that the polymerisation of this gas was spontaneous however slower at room temperature. The research thus focused on this polymerisation, and on the formula of the obtained polymer. After some generalities, the author reports the preparation, purification and storage and conservation of the carbon sub-oxide. The next parts report the kinetic study of thermal polymerisation, the study of polymerisation under γ rays, the study of the obtained polymer by using visible, UV and infrared spectroscopy, electronic paramagnetic resonance, and semi-conductivity measurements [fr

  7. Soya Fasulyesinden Konsantre Protein Üretimi ve Soya Ürünlerinin Bileşim Unsurları

    OpenAIRE

    Artık, Nevzat

    2014-01-01

    Soya fasulyesi üretimi ülkemizde 1981 verilerine göre 15000 ton düzeyindedir. Ortalama verim 88 kg da olarak gerçekleşmektedir. Ülkemizde üretilen soya fasulyesinin büyük bir çoğunluğu hayvan yemi olarak kullanılmaktadır. Bileşimi çok zengin olan ve hayvansal proteine eşdeğer oranda protein içeren soya fasulyesi gereğince değerlendirilememektedir. Soya fasulyesinden proteince zengin değişik ürünler elde edilmektedir. Bunlar soya unu, konsantre soya proteini, soya izolatı, et analogu ve ferme...

  8. Oxidation and thermal shock behavior of thermal barrier coated 18/10CrNi alloy with coating modifications

    Energy Technology Data Exchange (ETDEWEB)

    Guergen, Selim [Vocational School of Transportation, Anadolu University, Eskisehir (Turkmenistan); Diltemiz, Seyid Fehmi [Turkish Air Force1st Air Supply and Maintenance Center Command, Eskisehir (Turkmenistan); Kushan, Melih Cemal [Dept. of Mechanical Engineering, Eskisehir Osmangazi University, Eskisehir (Turkmenistan)

    2017-01-15

    In this study, substrates of 18/10CrNi alloy plates were initially sprayed with a Ni-21Cr-10Al-1Y bond coat and then with an yttria stabilized zirconia top coat by plasma spraying. Subsequently, plasma-sprayed Thermal barrier coatings (TBCs) were treated with two different modification methods, namely, vacuum heat treatment and laser glazing. The effects of modifications on the oxidation and thermal shock behavior of the coatings were evaluated. The effect of coat thickness on the bond strength of the coats was also investigated. Results showed enhancement of the oxidation resistance and thermal shock resistance of TBCs following modifications. Although vacuum heat treatment and laser glazing exhibited comparable results as per oxidation resistance, the former generated the best improvement in the thermal shock resistance of the TBCs. Bond strength also decreased as coat thickness increased.

  9. Development of new-generation dietary bread technologies by using soya processing products

    Directory of Open Access Journals (Sweden)

    M.A. Silagadze

    2017-06-01

    Full Text Available In order to develop low-calorie high-biological value dietary bread, we used the soya processing products – roasted full fat soya flour, soya milk and soya pomace. There has been studied their chemical and micro nutrient composition. The study shows that the soya processing products have low energy and high biological value, and exhibit low glycemic index that makes them very attractive for the design of dietary food products. In order to increase bioavailability of soya, we carried out its sprouting. We studied the impact of different technological factors on the accumulation dynamics of highly digestible components of soya. based on the studies of the separate and complex influence of the soya processing products on the quality of whole wheat bread, there have been determined the optimal doses of food additives. There has been developed a new-generation dietary product with the trade name “Our Daily Bread”, as well as its making technology.

  10. Grain product of 34 soya mutant lines

    International Nuclear Information System (INIS)

    Salmeron E, J.; Mastache L, A. A.; Valencia E, F.; Diaz V, G. E.; Cervantes S, T.; De la Cruz T, E.; Garcia A, J. M.; Falcon B, T.; Gatica T, M. A.

    2009-01-01

    This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R 4 M 18 ) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co 60 gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L 25 and L 32 produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

  11. The fate of phosphorus fertilizer in Amazon soya bean fields.

    Science.gov (United States)

    Riskin, Shelby H; Porder, Stephen; Neill, Christopher; Figueira, Adelaine Michela e Silva; Tubbesing, Carmen; Mahowald, Natalie

    2013-06-05

    Fertilizer-intensive soya bean agriculture has recently expanded in southeastern Amazonia, and whereas intensive fertilizer use in the temperate zone has led to widespread eutrophication of freshwater ecosystems, the effects in tropical systems are less well understood. We examined the fate of fertilizer phosphorus (P) by comparing P forms and budgets across a chronosequence of soya bean fields (converted to soya beans between 2003 and 2008) and forests on an 800 km(2) soya bean farm in Mato Grosso, Brazil. Soya bean fields were fertilized with 50 kg P ha(-1) yr(-1) (30 kg P ha(-1) yr(-1) above what is removed in crops). We used modified Hedley fractionation to quantify soil P pools and found increases in less-plant-available inorganic pools and decreases in organic pools in agricultural soils compared with forest. Fertilizer P did not move below 20 cm. Measurements of P sorption capacity suggest that while fertilizer inputs quench close to half of the sorption capacity of fast-reacting pools, most added P is bound in more slowly reacting pools. Our data suggest that this agricultural system currently has a low risk of P losses to waterways and that long time-scales are required to reach critical soil thresholds that would allow continued high yields with reduced fertilizer inputs.

  12. Energy recovery efficiency and cost analysis of VOC thermal oxidation pollution control technology.

    Science.gov (United States)

    Warahena, Aruna S K; Chuah, Yew Khoy

    2009-08-01

    Thermal oxidation of VOC is extremely energy intensive, and necessitates high efficiency heat recovery from the exhaust heat. In this paper, two independent parameters heat recovery factor (HRF) and equipment cost factor (ECF) are introduced. HRF and ECF can be used to evaluate separately the merits of energy efficiency and cost effectiveness of VOC oxidation systems. Another parameter equipment cost against heat recovery (ECHR) which is a function of HRF and ECF is introduced to evaluate the merit of different systems for the thermal oxidation of VOC. Respective cost models were derived for recuperative thermal oxidizer (TO) and regenerative thermal oxidizer (RTO). Application examples are presented to show the use and the importance of these parameters. An application examples show that TO has a lower ECF while RTO has a higher HRF. However when analyzed using ECHR, RTO would be of advantage economically in longer periods of use. The analytical models presented can be applied in similar environmental protection systems.

  13. A proteomic study to identify soya allergens--the human response to transgenic versus non-transgenic soya samples.

    Science.gov (United States)

    Batista, Rita; Martins, Isabel; Jeno, Paul; Ricardo, Cândido Pinto; Oliveira, Maria Margarida

    2007-01-01

    In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment. Copyright (c) 2007 S. Karger AG, Basel.

  14. Quorum Quenching Bacillus sonorensis Isolated from Soya Sauce Fermentation Brine

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2012-03-01

    Full Text Available An N-acylhomoserine lactone (AHL-degrading bacterial strain, L62, was isolated from a sample of fermentation brine of Chinese soya sauce by using rich medium agar supplemented with soya sauce (10% v/v. L62, a rod-shaped Gram positive bacterium with amylolytic activity, was phylogentically related to Bacillus sonorensis by 16S ribosomal DNA and rpoB sequence analyses. B. sonorensis L62 efficiently degraded N-3-oxohexanoyl homoserine lactone and N-octanoylhomoserine lactone. However, the aiiA homologue, encoding an autoinducer inactivation enzyme catalyzing the degradation of AHLs, was not detected in L62, suggesting the presence of a different AHL-degrading gene in L62. To the best of our knowledge, this is the first report of AHL-degrading B. sonorensis from soya sauce liquid state fermentation.

  15. Effect of thermal treatment conditions on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid

    International Nuclear Information System (INIS)

    Gorshkova, T.P.; Tarasova, D.V.; Olen'kova, I.P.; Andrushkevich, T.V.; Nikoro, T.A.

    1984-01-01

    The effect of thermal treatment conditions (temperature and gas medium) on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid is investigated. It is shown that active and selective catalysts are formed in the course of thermal decomposition of the drying product of ammonium metavanadate and paramolybdate under the conditions ensuring the vanadium ion reduction up to tetravalent state with conservation of molybdenum oxidation degree equal to 6. It is possible to realize it either by treatment of the catalyst calcinated in the air flow at 300 deg by the reaction mixture at the activation stage or by gas-reducer flow treatment at 280 deg. Thermal treatment in the reducing medium of the oxidized catalyst does not lead to complete regeneration of its properties

  16. Thermally and Electrically Conductive Nanopapers from Reduced Graphene Oxide: Effect of Nanoflakes Thermal Annealing on the Film Structure and Properties.

    Science.gov (United States)

    Bernal, M Mar; Tortello, Mauro; Colonna, Samuele; Saracco, Guido; Fina, Alberto

    2017-12-05

    In this study, we report a novel strategy to prepare graphene nanopapers from direct vacuum filtration. Instead of the conventional method, i.e., thermal annealing nanopapers at extremely high temperatures prepared from graphene oxide (GO) or partially reduced GO, we fabricate our graphene nanopapers directly from suspensions of fully reduced graphene oxide (RGO), obtained after RGO and thermal annealing at 1700 °C in vacuum. By using this approach, we studied the effect of thermal annealing on the physical properties of the macroscopic graphene-based papers. Indeed, we demonstrated that the enhancement of the thermal and electrical properties of graphene nanopapers prepared from annealed RGO is strongly influenced by the absence of oxygen functionalities and the morphology of the nanoflakes. Hence, our methodology can be considered as a valid alternative to the classical approach.

  17. Türkiye’de Yetiştirilen bazı Soya Varyetelerinden Elde Edilen Soya Sütlerinin Amino Asit Profilinin Belirlenmesi

    OpenAIRE

    Artık, Nevzat

    1989-01-01

    Bu araştırmada Türkiye’de yetiştirilen 5 farklı soya varyetesinden üretilen soya sütlerinin amino asit profilleri incelenmiştir. Ayrıca Japon soya varyetesi amino asit bileşimi ile karşılaştırma yapılmıştır. Soya sütlerinde esansiyel amino asitler yüksek düzeyde bulunmuştur. Esansiyel amino asit miktarı tüm soya varyetelerinde 4.125, 4.922 (mg/g) sınırları içinde değişmektedir. Bu özelliği ile soya sütü insan beslenmesinde önemli bir gıda maddesidir.  

  18. Türkiye’de Yetiştirilen bazı Soya Varyetelerinden Elde Edilen Soya Sütlerinin Amino Asit Profilinin Belirlenmesi

    Directory of Open Access Journals (Sweden)

    Nevzat Artık

    2015-02-01

    Full Text Available Bu araştırmada Türkiye’de yetiştirilen 5 farklı soya varyetesinden üretilen soya sütlerinin amino asit profilleri incelenmiştir. Ayrıca Japon soya varyetesi amino asit bileşimi ile karşılaştırma yapılmıştır. Soya sütlerinde esansiyel amino asitler yüksek düzeyde bulunmuştur. Esansiyel amino asit miktarı tüm soya varyetelerinde 4.125, 4.922 (mg/g sınırları içinde değişmektedir. Bu özelliği ile soya sütü insan beslenmesinde önemli bir gıda maddesidir.

  19. Immune response in mice to ingested soya protein: antibody production, oral tolerance and maternal transfer

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Pedersen, Susanne Brix; Frøkiær, Hanne

    2004-01-01

    by ELISA, and to the presence of oral tolerance detected as a suppressed antibody and cell-proliferation response upon immunisation with soya protein. F0 mice generated soya-specific antibodies, while oral tolerance to the same soya proteins was also clearly induced. When F0 dams were transferred to soya...... antibody response in the offspring, bat in this case in the absence of oral tolerance. This indicates that, under certain conditions, factors involved in spontaneous antibody production can be transmitted from mother to offspring. Understanding the immune response to soya protein ingested under healthy...

  20. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion

    DEFF Research Database (Denmark)

    Wickman, B.; da Silva Fanta, Alice Bastos; Burrows, Andrew

    2017-01-01

    Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes...... considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation...

  1. Analisa Heat Balance Thermal Oxidizer dengan Waste Heat Recovery Unit

    Directory of Open Access Journals (Sweden)

    Alfian Bani Susiloputra

    2017-03-01

    Full Text Available Central Processing Plant (CPP merupakan plant yang memproses feed gas hingga menjadi natural gas siap pakai. Pengolahan feed gas di CPP menimbulkan dampak limbah berupa waste gas. Thermal Oxidizer (TOX memiliki peran penting dalam mengatasi waste gas. Energi panas gas buang (flue gas dimanfaatkan pada Waste Heat Recovery Unit (WHRU yang berada diatas chamber, digunakan untuk memanaskan hot oil. Kondisi operasional pembakaran TOX di CPP saat ini, jumlah input sangat berbeda dengan desain awal. Suhu pembakaran juga sangat tinggi, yaitu diatas 1.144 K. Sementara itu WHRU belum berjalan secara normal, suhu hot oil pada outlet WHRU masih 438-444 K. Analisa pembakaran TOX dilakukan dengan analisa termodinamika pada jumlah bahan bakar serta jumlah excess air untuk mendapatkan pembakaran sempurna pada suhu ideal chamber, yaitu 1.088-1.144 K. Bahan bakar yang digunakan sejumlah 60%-100% dari fuel gas operasional, sedangkan excess air yang digunakan 10%-35%. Selain itu pemanfaatan energi panas flue gas pada WHRU dilakukan analisa supaya suhu hot oil keluar WHRU mencapai 449 K. Analisa WHRU dilakukan dengan analisa perpindahan panas, untuk mendapatkan flowrate dari hot oil dari suhu dan laju aliran massa flue gas hasil variasi pembakaran TOX tersebut. Dari penelitian ini, suhu TOX hasil pembakaran operasional yang sesuai dengan desain awal yaitu pada 60% fuel gas dengan excess air (EA antara 30% hingga 35%. Pada 60% fuel gas dengan EA antara 30% hingga 35% didapatkan suhu antara 1.095 K hingga 1.138 K. Pada hasil analisa WHRU, untuk mencapai suhu hot oil sebesar 449,817 K pada variasi TOX tersebut diperlukan laju aliran massa hot oil sebesar 1.257.720 kg/jam dan 1.481.420 kg/jam.

  2. The Wear behavior of UHMWPE against Surface Modified CP-Titanium by Thermal Oxidation

    Directory of Open Access Journals (Sweden)

    B.T. Prayoga

    2016-12-01

    Full Text Available The effects of thermal oxidation duration on hardness, roughness, and wettability of the CP-titanium surfaces were investigated in this paper. The thermal oxidation treatment was done at 700 oC for 12-36 hours in an air atmosphere. The wear behavior of the UHMWPE sliding against treated thermal oxidation of the CP-titanium was tested by a pin-on-plate tribometer under lubrication of the solution of 75 % distilled water and 25 % bovine serum. The results showed that the layer of the oxide titanium was formed on the surface after being treated by the thermal oxidation for 12-36 hours. The oxide titanium layer was dominated by rutile form of TiO2, that offers an improvement of hardness and wettability of the CP-titanium surfaces. The average wear factor of the UHMWPE reduced significantly when the sliding against of the CP-titanium was modified by the thermal oxidation, and the lowest average wear factor was reached when the sliding against the 12 hour oxidized CP-titanium counterfaces.

  3. Thermal resistances of crystalline and amorphous few-layer oxide thin films

    Directory of Open Access Journals (Sweden)

    Liang Chen

    2017-11-01

    Full Text Available Thermal insulation at nanoscale is of crucial importance for non-volatile memory devices such as phase change memory and memristors. We perform non-equilibrium molecular dynamics simulations to study the effects of interface materials and structures on thermal transport across the few-layer dielectric nanostructures. The thermal resistance across few-layer nanostructures and thermal boundary resistance at interfaces consisting of SiO2/HfO2, SiO2/ZrO2 or SiO2/Al2O3 are obtained for both the crystalline and amorphous structures. Based on the comparison temperature profiles and phonon density of states, we show that the thermal boundary resistances are much larger in crystalline few-layer oxides than the amorphous ones due to the mismatch of phonon density of state between distinct oxide layers. Compared with the bulk SiO2, the increase of thermal resistance across crystalline few-layer oxides results from the thermal boundary resistance while the increase of thermal resistance across amorphous few-layer oxides is attributed to the lower thermal conductivity of the amorphous thin films.

  4. Obtaining and a comprehensive study of highly bioavailable functional food additives based on Georgian soya varieties

    Directory of Open Access Journals (Sweden)

    M.A. Silagadze

    2017-09-01

    Full Text Available Overall chemical and micro-nutrient composition of Georgian soya varieties grown in different districts of West Georgia have been studied. It was established that “Gurian” soya from Lanchkhuti district is distinguished by the highest content of proteins, fats and dietary fibers that ensures its high functional properties. 18 Aminoacids, mostly fixed in the fractions of globulin and albumin, were identified in protein fractions of Georgian soya varieties that indicates to their high biological value. Highly-bioavailable foods: soya milk, soya pomace and soya flour were obtained during the soya processing; they were tested as food additives in the production of whole wheat bread. Their impact on the fermentation process of wheat dough was studied and the optimal parameters of this process were developed.

  5. Thermal oxidative degradation behaviours of flame-retardant thermotropic liquid crystal copolyester/PET blends

    International Nuclear Information System (INIS)

    Du Xiaohua; Zhao Chengshou; Wang Yuzhong; Zhou Qian; Deng Yi; Qu Minghai; Yang Bing

    2006-01-01

    The flame retardancy and the thermal oxidative degradation behaviors of the blend of poly(ethylene terephthalate) (PET) with a kind of phosphorus-containing thermotropic liquid crystal copolyester (TLCP) with high flame retardancy (limited oxygen index, 70%) have been investigated by oxygen index test (LOI), UL-94 rating and thermogravimetric analysis (TGA) in air. The results show that TLCP can dramatically improve the flame retardancy and the melt dripping behavior of PET. Moreover, the apparent activation energies of thermal oxidative degradation of the blends were evaluated using Kissinger and Flynn-Wall-Ozawa methods. It is found that addition of TLCP improve thermal stability and restrain thermal decomposition of PET in air, especially at the primary degradation stage. Py-GC/MS analysis shows that there are remarkable changes in the pyrolysis products when TLCP are blended into PET. The interaction between TLCP and PET has changed their thermal oxidative degradation mechanism

  6. ZnO Micro- and Nanostructures Obtained by Thermal Oxidation: Microstructure, Morphogenesis, Optical, and Photoluminescence Properties

    OpenAIRE

    Alejandro Escobedo-Morales; Rubén J. Aranda-García; Ernesto Chigo-Anota; Armando Pérez-Centeno; Antonio Méndez-Blas; Carlos G. Arana-Toro

    2016-01-01

    ZnO micro- and nanostructures were obtained through thermal oxidation of Zn powders at high temperature under air atmosphere. A detailed study of the microstructure, morphology, optical, and photoluminescence properties of the generated products at different stages of thermal oxidation is presented. It was found that the exposure time has a strong influence on the resulting morphology. The morphogenesis of the different ZnO structures is discussed, and experimental parameters for fabricating ...

  7. Effects of Fermented Soya Bean Supplements on Serum Insulin and ...

    African Journals Online (AJOL)

    This study aimed to evaluate the effects of fermented soya bean supplements on serum insulin and leptin levels of high fat diet-induced type 2 diabetes mellitus in rabbits. Methods: Twenty rabbits of both sexes weighing, 1–2kg were used. Type 2 diabetes was induced by feeding the animals with a high fat diet for eight ...

  8. Utilization of soya protein as an alternative protein source in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-05

    Jan 5, 2009 ... source in Oreochromis niloticus diet: Growth performance ... The effect of replacing fish protein with soya protein in tilapia (Oreochromis niloticus) diets was ..... Thomassen MS, Rosjo C (1989). Different fats in feed for salmon: influence on sensory parameters, growth rate and fatty acids in muscle and heart.

  9. Mechanism of antioxidant interaction on polymer oxidation by thermal and radiation ageing

    International Nuclear Information System (INIS)

    Seguchi, Tadao; Tamura, Kiyotoshi; Shimada, Akihiko; Sugimoto, Masaki; Kudoh, Hisaaki

    2012-01-01

    The mechanism of polymer oxidation by radiation and thermal ageing was investigated for the life evaluation of cables installed in radiation environments. The antioxidant as a stabilizer was very effective for thermal oxidation with a small content in polymers, but was not effective for radiation oxidation. The ionizing radiation induced the oxidation to result in chain scission even at low temperature, because the free radicals were produced and the antioxidant could not stop the oxidation of radicals with the chain scission. A new mechanism of antioxidant effect for polymer oxidation was proposed. The effect of antioxidant was not the termination of free radicals in polymer chains such as peroxy radicals, but was the depression of initial radical formation in polymer chains by thermal activation. The antioxidant molecule was assumed to delocalize the activated energy in polymer chains by the Boltzmann statics (distribution) to result in decrease in the probability of radical formation at a given temperature. The interaction distance (delocalization volume) by one antioxidant molecule was estimated to be 5–10 nm by the radius of sphere in polymer matrix, though the value would depend on the chemical structure of antioxidant. - Highlights: ► Interaction of antioxidant on polymer oxidation is discussed for thermal and radiation ageings. ► Antioxidant is very effective for thermal oxidation, but not for radiation induced oxidation. ► Interaction of antioxidant is not the termination reaction of radicals on polymers. ► Antioxidant is supposed to reduce the provability of polymer radical formation by thermal activation. ► Mechanism of polymer oxidation may not be chain reaction via peroxy radical and hydro-peroxide.

  10. Iridescent cellulose nanocrystal/polyethylene oxide composite films with low coefficient of thermal expansion

    Science.gov (United States)

    Jairo A. Diaz; Julia L. Braun; Robert J. Moon; Jeffrey P. Youngblood

    2015-01-01

    Simultaneous control over optical and thermal properties is particularly challenging and highly desired in fields like organic electronics. Here we incorporated cellulose nanocrystals (CNCs) into polyethylene oxide (PEO) in an attempt to preserve the iridescent CNC optical reflection given by their chiral nematic organisation, while reducing the composite thermal...

  11. Conductive ink containing thermally exfoliated graphite oxide and method a conductive circuit using the same

    Science.gov (United States)

    Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

    2011-01-01

    A conductive ink containing a conductive polymer, wherein the conductive polymer contains at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, and it use in a method for making a conductive circuit.

  12. Electrospray painted article containing thermally exfoliated graphite oxide and method for their manufacture

    Science.gov (United States)

    Korkut, Sibel (Inventor); Prud'Homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

    2011-01-01

    A painted polymer part containing a conductive polymer composition containing at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 sq m/g to 2600 sq m/g, wherein the painted polymer part has been electrospray painted.

  13. Investigation of thermal oxidative break-down of polyethylene films modified with grafted polyacrylonitrile

    International Nuclear Information System (INIS)

    Krul', L.P.; Gert, E.V.

    1981-01-01

    Thermal oxidative destruction of polyethylene (PE) films modified by radiation (#betta#-radiation, dose rate is 0.56 Mrad/hr) liquid-phase graft polymerization of acrylonitrile (AN) has been studied. Comparative stability of grafted copolymers, homopolymers and mechanical mixtures of PE and PAN (polyacrylonitrile) to thermal oxidative destruction is studied using the derivatographic method. It is shown that graft of PAN considerably decelerates the development of oxidative and destructive processes in PE, at that, the efficiency of PE chain stabilization increases with the increase of grafted PAN amount. The sample with PAN content x=0.367 (in parts of the mass of grafted film) possesses the highest stability

  14. Iodine doping effects on the lattice thermal conductivity of oxidized polyacetylene nanofibers

    Science.gov (United States)

    Bi, Kedong; Weathers, Annie; Matsushita, Satoshi; Pettes, Michael T.; Goh, Munju; Akagi, Kazuo; Shi, Li

    2013-11-01

    Thermal transport in oxidized polyacetylene (PA) nanofibers with diameters in the range between 74 and 126 nm is measured with the use of a suspended micro heater device. With the error due to both radiation and contact thermal resistance corrected via a differential measurement procedure, the obtained thermal conductivity of oxidized PA nanofibers varies in the range between 0.84 and 1.24 W m-1 K-1 near room temperature, and decreases by 40%-70% after iodine doping. It is also found that the thermal conductivity of oxidized PA nanofibers increases with temperature between 100 and 350 K. Because of exposure to oxygen during sample preparation, the PA nanofibers are oxidized to be electrically insulating before and after iodine doping. The measurement results reveal that iodine doping can result in enhanced lattice disorder and reduced lattice thermal conductivity of PA nanofibers. If the oxidation issue can be addressed via further research to increase the electrical conductivity via doping, the observed suppressed lattice thermal conductivity in doped polymer nanofibers can be useful for the development of such conducting polymer nanostructures for thermoelectric energy conversion.

  15. Preparation of Graphene Oxide Stabilized Nickel Nanoparticles with Thermal Effusivity Properties by Laser Ablation Method

    Directory of Open Access Journals (Sweden)

    Amir Reza Sadrolhosseini

    2013-01-01

    Full Text Available Nickel nanoparticles were dispersed uniformly in a graphene oxide solution, using a laser ablation technique with different ablation times that ranged from 5 to 20 minutes. The results indicate that the nickel nanoparticle sizes inside the graphene oxide decreased, and the volume fraction for the nickel nanoparticles in the graphene oxide increased with an increasing ablation time. Further, using Fourier Transform Infrared Spectroscopy, the nickel nanoparticles in the graphene oxide demonstrate greater stability from possible agglomeration when the nanoparticle was capped with oxygen from the carboxyl group of the graphene oxide. The thermal effusivity of the graphene oxide and nickel nanoparticle graphene oxide composite was measured using a photoacoustic technique. The concentration of graphene oxide shifted from 0.05 mg/L to 2 mg/L, and the thermal effusivity increased from 0.153 W·s1/2·cm−2·K−1 to 0.326 W·s1/2·cm−2·K−1. In addition, the thermal effusivity of the nickel nanoparticles graphene oxide composite increased with an increase in the volume fraction of nickel nanoparticles from 0.1612 W·s1/2·cm−2·K−1 to 0.228 W·s1/2·cm−2·K−1.

  16. ZnO Micro- and Nanostructures Obtained by Thermal Oxidation: Microstructure, Morphogenesis, Optical, and Photoluminescence Properties

    Directory of Open Access Journals (Sweden)

    Alejandro Escobedo-Morales

    2016-10-01

    Full Text Available ZnO micro- and nanostructures were obtained through thermal oxidation of Zn powders at high temperature under air atmosphere. A detailed study of the microstructure, morphology, optical, and photoluminescence properties of the generated products at different stages of thermal oxidation is presented. It was found that the exposure time has a strong influence on the resulting morphology. The morphogenesis of the different ZnO structures is discussed, and experimental parameters for fabricating ZnO tetrapods, hollow, core-shell, elongated, or rounded structures by thermal oxidation method are proposed on the basis on the obtained results. Notoriously, the crystal lattice of the ZnO structures has negligible residual strain, although, the density of point defects increases when the thermal treatment is extended; as consequence, their visible luminescence upon UV excitation enhances.

  17. Coal Oxide as a Thermally Robust Carbon-Based Proton Conductor.

    Science.gov (United States)

    Hatakeyama, Kazuto; Ogata, Chikako; Koinuma, Michio; Taniguchi, Takaaki; Hayami, Shinya; Kuroiwa, Keita; Matsumoto, Yasumichi

    2015-10-21

    Inexpensive solid proton conducting materials with high proton conductivity and thermal stability are necessary for practical solid state electrochemical devices. Here we report that coal oxide (CO) is a promising carbon-based proton conductor with remarkable thermal robustness. The CO produced by simple liquid-phase oxidation of coal demonstrates excellent dispersibility in water owing to the surface carboxyl groups. The proton conductivity of CO, 3.9 × 10(-3) S cm(-1) at 90% relative humidity, is as high as that of graphene oxide (GO). Remarkably, CO exhibits much higher thermal stability than GO, with CO retaining the excellent proton conductivity as well as the capacitance performance even after thermal annealing at 200 °C. Our study demonstrates that the chemical modification of the abundant coal provides proton conductors that can be used in practical applications for a wide range of energy devices.

  18. A recommendation for the thermal conductivity of oxide fuels

    International Nuclear Information System (INIS)

    Kang, K. H.; Ryu, H. J.; Song, K. C.; Yang, M. S.; Na, S. H.; Lee, Y. W.; Moon, H. S.; Kim, H. S.

    2004-01-01

    The thermal conductivity of nuclear fuel is one of the most important properties because it affects the fuel operating temperature. Therefore, it influences almost all the important processes occurred in nuclear fuel during irradiation, such as gas release, swelling and grain growth. The model of the thermal conductivity of nuclear fuel should be used in the codes to evaluate the performance of it analytically and be required in the nuclear fuel research and development. The thermal conductivity, k, of UO 2 depends on the deviation from stoichiometry, x, the burnup, b, and the fractional porosity, p, as well as the temperature, T: k = k(x, b, p, T), (1) Changes in thermal conductivity occur during irradiation because of fission-gas bubble formation, pores, cracks, fission product build-up and possible changes in the oxygen to uranium ratio (O/U). The dependence on temperature and porosity has been well studied and incorporated in computer codes used for the in-pile fuel behavior analysis. There are several studies on the effect of impurity on the thermal conductivity of UO 2 . In this paper, the variables affected on the thermal conductivity were studied. The available data of the thermal conductivity of UO 2 , UO 2+x , (U, Pu)O 2 , (U, Pu)O 2 and simulated fuel for irradiation fuel were reviewed and analyzed. The best models were recommended

  19. In vitro corrosion behavior and cellular response of thermally oxidized Zr-3Sn alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, F.Y.; Wang, B.L.; Qiu, K.J. [Center for Biomedical Materials and Engineering, Harbin Engineering University, Harbin 150001 (China); Li, H.F. [Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871 (China); Li, L. [Center for Biomedical Materials and Engineering, Harbin Engineering University, Harbin 150001 (China); Zheng, Y.F., E-mail: yfzheng@pku.edu.cn [Center for Biomedical Materials and Engineering, Harbin Engineering University, Harbin 150001 (China); Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871 (China); Han, Y. [State Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer A main monoclinic ZrO{sub 2} layer formed on ZrSn alloy after thermal oxidation. Black-Right-Pointing-Pointer Corrosion resistance of ZrSn alloy was improved with thermal oxidation. Black-Right-Pointing-Pointer The oxide layer inhibited the release of the ions into the mediums. Black-Right-Pointing-Pointer Oxidized ZrSn alloy exhibited an excellent in vitro biocompatibility. - Abstract: In this study, ZrSn alloy was thermally oxidized at 600 Degree-Sign C for 3 h and its morphological and structural characteristics, corrosion behavior, ion release and in vitro cytocompatibility were studied to evaluate the feasibility of applying it as dental implant. After oxidation, a dense black oxide layer formed on ZrSn alloy surface, which consisted of predominant monoclinic zirconia and a few non-stoichiometric oxides. The scratching and water contact angle test results demonstrated that the oxide layer exhibited good adhesion strength and similar hydrophilicity to zirconia. The oxidized ZrSn alloy showed higher corrosion resistance, as indicated by far lower corrosion current density and passive current density compared to pure Ti and untreated ZrSn alloy in artificial saliva with and without H{sub 2}O{sub 2}. The amount of ions released from the oxidized ZrSn alloy was much lower than that dissolved from pure Ti in simulated corrosive oral mediums. Moreover, the oxidized ZrSn alloy did not present any significant toxic effect to both osteoblast-like cells and fibroblast cells, and osteoblast-like cells could adhere well onto the surface and exhibited a good proliferative pattern. The combination of improved surface properties, superior corrosion resistance and good biocompatibility made the oxidized ZrSn alloy promising for oral implantology application.

  20. Preparation and investigations of thermal properties of copper oxide ...

    Indian Academy of Sciences (India)

    EDX) and scan- ning electron microscope (SEM) were used to determine the chemical structure, crystalloid phase, chemical com- position and microstructure of the composites, respectively. The thermal properties were investigated by differen-.

  1. Thermal processing and native oxidation of silicon nanoparticles

    International Nuclear Information System (INIS)

    Winters, Brandon J.; Holm, Jason; Roberts, Jeffrey T.

    2011-01-01

    In this study, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and electron energy loss spectroscopy (EELS) were used to investigate in-air oxidation of silicon nanoparticles ca. 11 nm in diameter. Particle samples were prepared first by extracting them from an RF plasma synthesis reactor, and then heating them in an inert carrier gas stream. The resulting particles had varying surface hydrogen coverages and relative amounts of SiH x (x = 1, 2, and 3), depending on the temperature to which they had been heated. The particles were allowed to oxidize in-air for several weeks. FTIR, XPS, and EELS analyses that were performed during this period clearly establish that adsorbed hydrogen retards oxidation, although in complex ways. In particular, particles that have been heated to intermediate hydrogen coverages oxidize more slowly in air than do freshly generated particles that have a much higher hydrogen content. In addition, the loss of surface hydride species at high processing temperatures results in fast initial oxidation and the formation of a self-limiting oxide layer. Analogous measurements made on deuterium-covered particles show broadly similar behavior; i.e., that oxidation is the slowest at some intermediate coverage of adsorbed deuterium.

  2. Thermal oxidation of reactively sputtered amorphous W80N20 films

    International Nuclear Information System (INIS)

    Vu, Q.T.; Pokela, P.J.; Garden, C.L.; Kolawa, E.; Raud, S.; Nicolet, M.

    1990-01-01

    The oxidation behavior of reactively sputtered amorphous tungsten nitride of composition W 80 N 20 was investigated in dry and wet oxidizing ambient in the temperature range of 450 degree C--575 degree C. A single WO 3 oxide phase is observed. The growth of the oxide follows a parabolic time dependence which is attributed to a process controlled by the diffusivity of the oxidant in the oxide. The oxidation process is thermally activated with an activation energy of 2.5±0.05 eV for dry ambient and 2.35±0.05 eV for wet ambient. The pre-exponential factor of the reaction constant for dry ambient is 1.1x10 21 A 2 /min; that for wet ambient is only about 10 times less and is equal to 1.3x10 20 A 2 /min

  3. A Novel Investigation of the Formation of Titanium Oxide Nanotubes on Thermally Formed Oxide of Ti-6Al-4V.

    Science.gov (United States)

    Butt, Arman; Hamlekhan, Azhang; Patel, Sweetu; Royhman, Dmitry; Sukotjo, Cortino; Mathew, Mathew T; Shokuhfar, Tolou; Takoudis, Christos

    2015-10-01

    Traditionally, titanium oxide (TiO2) nanotubes (TNTs) are anodized on Ti-6Al-4V alloy (Ti-V) surfaces with native TiO2 (amorphous TiO2); subsequent heat treatment of anodized surfaces has been observed to enhance cellular response. As-is bulk Ti-V, however, is often subjected to heat treatment, such as thermal oxidation (TO), to improve its mechanical properties. Thermal oxidation treatment of Ti-V at temperatures greater than 200°C and 400°C initiates the formation of anatase and rutile TiO2, respectively, which can affect TNT formation. This study aims at understanding the TNT formation mechanism on Ti-V surfaces with TO-formed TiO2 compared with that on as-is Ti-V surfaces with native oxide. Thermal oxidation-formed TiO2 can affect TNT formation and surface wettability because TO-formed TiO2 is expected to be part of the TNT structure. Surface characterization was carried out with field emission scanning electron microscopy, energy dispersive x-ray spectroscopy, water contact angle measurements, and white light interferometry. The TNTs were formed on control and 300°C and 600°C TO-treated Ti-V samples, and significant differences in TNT lengths and surface morphology were observed. No difference in elemental composition was found. Thermal oxidation and TO/anodization treatments produced hydrophilic surfaces, while hydrophobic behavior was observed over time (aging) for all samples. Reduced hydrophobic behavior was observed for TO/anodized samples when compared with control, control/anodized, and TO-treated samples. A method for improved surface wettability and TNT morphology is therefore discussed for possible applications in effective osseointegration of dental and orthopedic implants.

  4. Effects of solid fission products forming dissolved oxide (Nd) and metallic precipitate (Ru) on the thermal conductivity of uranium base oxide fuel

    International Nuclear Information System (INIS)

    Kim, Dong-Joo; Yang, Jae-Ho; Kim, Jong-Hun; Rhee, Young-Woo; Kang, Ki-Won; Kim, Keon-Sik; Song, Kun-Woo

    2007-01-01

    The effects of solid fission products on the thermal conductivity of uranium base oxide nuclear fuel were experimentally investigated. Neodymium (Nd) and ruthenium (Ru) were added to represent the physical states of solid fission products such as 'dissolved oxide' and 'metallic precipitate', respectively. Thermal conductivity was determined on the basis of the thermal diffusivity, density and specific heat values. The effects of the additives on the thermal conductivity were quantified in the form of the thermal resistivity equation - the reciprocal of the phonon conduction equation - which was determined from the measured data. It is concluded that the thermal conductivity of the irradiated nuclear fuel is affected by both the 'dissolved oxide' and the 'metallic precipitate', however, the effects are in the opposite direction and the 'dissolved oxide' influences the thermal conductivity more significantly than that of the 'metallic precipitate'

  5. Deuterium permeation behavior of HTUPS4 steel with thermal oxidation layer

    International Nuclear Information System (INIS)

    Xu, Yu-Ping; Liu, Feng; Zhao, Si-Xiang; Li, Xiao-Chun; Wang, Jing; An, Zhong-Qing; Lu, Tao; Liu, Hao-Dong; Ding, Fang; Zhou, Hai-Shan; Luo, Guang-Nan

    2016-01-01

    The permeation behavior of creep-resistant, Al 2 O 3 -forming HTUPS austenitic stainless steels was studied using a gas driven permeation (GDP) device. The steel samples were first thermal oxidized at air condition, followed by GDP experiments. The permeability and diffusion coefficients of oxidized samples and bare 316L steels were derived and compared. In order to characterize the oxide layer, X-ray photoelectron spectroscopy was performed. An oxide layer with a thickness of 200 nm which mainly consists of Al 2 O 3 was detected.

  6. Effect of adsorbed polyaniline on the thermal stability of iron and arsenic oxides

    Directory of Open Access Journals (Sweden)

    Robson Fernandes de Farias

    2000-06-01

    Full Text Available Iron and arsenic oxide grains are coated with the conducting organic polymer polyaniline. The obtained samples were characterized by infrared spectroscopy, SEM, conducting measurements and thermogravimetry. The thermal stability of both oxides are increased. For As2O3 the sublimation temperature is increased from 165ºC in the pure oxide to 206ºC in the polymer modified sample. The pure Fe3O4 sample exhibits sublimation at 780ºC whereas the polyaniline coated oxide is stable until at least 1000ºC.

  7. The oxidation behavior of classical thermal barrier coatings exposed to extreme temperature

    Directory of Open Access Journals (Sweden)

    Alina DRAGOMIRESCU

    2017-03-01

    Full Text Available Thermal barrier coatings (TBC are designed to protect metal surfaces from extreme temperatures and improve their resistance to oxidation during service. Currently, the most commonly used systems are those that have the TBC structure bond coat (BC / top coat (TC layers. The top coat layer is a ceramic layer. Oxidation tests are designed to identify the dynamics of the thermally oxide layer (TGO growth at the interface of bond coat / top coat layers, delamination mechanism and the TBC structural changes induced by thermal conditions. This paper is a short study on the evolution of aluminum oxide protective layer along with prolonged exposure to the testing temperature. There have been tested rectangular specimens of metal super alloy with four surfaces coated with a duplex thermal barrier coating system. The specimens were microscopically and EDAX analyzed before and after the tests. In order to determine the oxide type, the samples were analyzed using X-ray diffraction. The results of the investigation are encouraging for future studies. The results show a direct relationship between the development of the oxide layer and long exposure to the test temperature. Future research will focus on changing the testing temperature to compare the results.

  8. Inverse association between soya food consumption and insulin resistance in Japanese adults.

    Science.gov (United States)

    Nakamoto, Mariko; Uemura, Hirokazu; Sakai, Tohru; Katsuura-Kamano, Sakurako; Yamaguchi, Miwa; Hiyoshi, Mineyoshi; Arisawa, Kokichi

    2015-08-01

    The purpose of the present study was to examine the association between soya food consumption and insulin resistance using baseline data of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study in Tokushima, Japan. This cross-sectional study included 1274 subjects, aged 34-70 years at baseline, living in Tokushima Prefecture between 2008 and 2013. Fasting blood samples were collected and information on lifestyle characteristics including soya food intake and medical history were obtained using a structured self-administered questionnaire. The homeostasis model assessment of insulin resistance (HOMA-IR) was measured and those with HOMA-IR ≥ 2.5 were defined as having insulin resistance. Multiple logistic regression models were used to analyse the association between soya product intake and the prevalence of insulin resistance. Rural communities located in Tokushima Prefecture, Japan, between 2008 and 2013. A total of 1148 adults (565 men and 583 women), aged 34-70 years. The frequency of intake of miso soup, total non-fried soya products and total soya products showed significant inverse dose-response relationships with insulin resistance, after adjustments for potential confounders. When soya product intake was calculated as soya protein and isoflavone, the odds ratios of insulin resistance decreased significantly as the estimated intake of soya protein increased. Furthermore, significant inverse dose-response relationships were observed for total non-fried soya products and total soya products, after adjustment for total vegetable or total fibre consumption. The present results indicate that the intake of soya products and non-fried soya products is associated with reduced insulin resistance in the Japanese population.

  9. New perspectives on thermal and hyperthermal oxidation of silicon surfaces

    Science.gov (United States)

    Khalilov, Umedjon

    The growth of (ultra)thin silica (SiO2) layers on crystalline silicon (c-Si) and controlling the thickness of SiO2 is an important issue in the fabrication of microelectronics and photovoltaic devices (e.g., MOSFETs, solar cells, optical fibers etc.). Such ultrathin oxide can be grown and tuned even at low temperature (including room temperature), by hyperthermal oxidation or when performed on non-planar Si surfaces (e.g., Si nanowires or spheres). However, hyperthermal silica growth as well as small Si-NW oxidation in general and the initial stages in particular have not yet been investigated in full detail. This work is therefore devoted to controlling ultrathin silica thickness on planar and non-planar Si surfaces, which can open new perspectives in nanodevice fabrication. The simulation of hyperthermal (1-100 eV) Si oxidation demonstrate that at low impact energy (transistors and photovoltaic devices in near-future nanotechnology. Above the transition temperature such core-shell nanowires are completely converted to a-SiO2 nanowires. It can be concluded that an accurate control over the interfacial stress by choosing a suitable oxidation temperature and Si-NW diameter can lead to precise nanoscale control over the Si-core radius. All investigations were carried out by applying molecular dynamics calculations using the ReaxFF potential, allowing a accurately study of the underpinning physical and chemical processes.

  10. Diseño de los procesos para industrializar la soya

    OpenAIRE

    Barrigas Romero, Cesar Orlando; Miranda, Luis

    2009-01-01

    El objetivo general es el diseño de los procesos y de las líneas de producción a escala semi industrial para la obtención de productos alimenticios a base de soya. Para ello, en la primera parte se describe a la soya como materia prima, en la fase experimental establecimos parámetros de proceso para estandarizar resultados con 1 kilo de soya como base a fin de obtener leche, queso y yogurt de soya con la parte líquida; y con la parte sólida un producto tipo granola y tortitas a base de la mez...

  11. Comparative physico-chemical evaluation of soymilk and soya cake ...

    African Journals Online (AJOL)

    The ash contents of soymilk were 0.40, 0.42, and 0.45% or A, B, and C respectively; soya cake recorded higher figures of 0.81, 0.79, and 0.79% for samples A, B, and C respectively. Raw and pasteurized soymilk stored at 4°C kept for 3 and 7 days respectively. The microbial loads of the raw soymilk were 3 x 105, 4 x 105 ...

  12. SO2 oxidation catalyst model systems characterized by thermal methods

    DEFF Research Database (Denmark)

    Hatem, G; Eriksen, Kim Michael; Gaune-Escard, M

    2002-01-01

    ) and Differential Scanning Calorimetry (DSC). Fundamental thermodynamic data like temperatures and molar heats of solid-solid transition and fusion, phase diagrams, heat capacities of solids and liquids, heat of mixing and heats of complex formation have been obtained and the results are discussed in relation...... to the mechanism Of SO2 oxidation by V2O5 based industrial catalysts....

  13. Synthesis and characterization of thermally oxidized ZnO films

    Indian Academy of Sciences (India)

    Administrator

    was investigated for some reducing gases such as acetone, methane and liquefied petroleum gas and it was observed that the films studied were selective to acetone. Keywords. Zinc oxide; structural analysis; optical parameters; electrical conductivity; gas sensitivity. 1. Introduction. In recent years, transparent conducting ...

  14. Thermal Stability Limits of Imidazolium Ionic Liquids Immobilized on Metal-Oxides.

    Science.gov (United States)

    Babucci, Melike; Akçay, Aslı; Balci, Volkan; Uzun, Alper

    2015-08-25

    Thermal stability limits of 33 imidazolium ionic liquids (ILs) immobilized on three of the most commonly used high surface area metal-oxides, SiO2, γ-Al2O3, and MgO, were investigated. ILs were chosen from a family of 13 cations and 18 anions. Results show that the acidity of C2H of an imidazolium ring is one of the key factors controlling the thermal stability. An increase in C2H bonding strength of ILs leads to an increase in their stability limits accompanied by a decrease in interionic energy. Systematic changes in IL structure, such as changes in electronic structure and size of anion/cation, methylation on C2 site, and substitution of alkyl groups on the imidazolium ring with functional groups have significant effects on thermal stability limits. Furthermore, thermal stability limits of ILs are influenced strongly by acidic character of the metal-oxide surface. Generally, as the point of zero charge (PZC) of the metal-oxide increases from SiO2 to MgO, the interactions of IL and metal-oxide dominate over interionic interactions, and metal-oxide becomes the significant factor controlling the stability limits. However, thermal stability limits of some ILs show the opposite trend, as the chemical activities of the cation functional group or the electron donating properties of the anion alter IL/metal-oxide interactions. Results presented here can help in choosing the most suitable ILs for materials involving ILs supported on metal-oxides, such as for supported ionic liquid membranes (SILM) in separation applications or for solid catalyst with ionic liquid layer (SCILL) and supported ionic liquid phase (SILP) catalysts in catalysis.

  15. Thermally induced all-optical inverter and dynamic hysteresis loops in graphene oxide dispersions.

    Science.gov (United States)

    Melle, Sonia; Calderón, Oscar G; Egatz-Gómez, Ana; Cabrera-Granado, E; Carreño, F; Antón, M A

    2015-11-01

    We experimentally study the temporal dynamics of amplitude-modulated laser beams propagating through a water dispersion of graphene oxide sheets in a fiber-to-fiber U-bench. Nonlinear refraction induced in the sample by thermal effects leads to both phase reversing of the transmitted signals and dynamic hysteresis in the input-output power curves. A theoretical model including beam propagation and thermal lensing dynamics reproduces the experimental findings.

  16. Characteristics of thermally reduced graphene oxide and applied for dye-sensitized solar cell counter electrode

    International Nuclear Information System (INIS)

    Ho, Ching-Yuan; Wang, Hong-Wen

    2015-01-01

    Graphical abstract: Experimental process: (1) graphite oxidized to graphene oxide; (2) thermal reduction from graphene oxide to graphene; (3) applying to DSSC counter electrode. - Highlights: • Intercalated defects were eliminated by increasing reduction temperature of GO. • High reduction temperature of tGP has lower resistance, high the electron lifetime. • Higher thermal reduction of GO proposes electrocatalytic properties. • DSSC using tGP 250 as counter electrode has energy conversion efficiency of 3.4%. - Abstract: Graphene oxide (GO) was synthesized from a flake-type of graphite powder, which was then reduced to a few layers of graphene sheets using the thermal reduction method. The surface morphology, phase crystallization, and defect states of the reduced graphene were determined from an electron microscope equipped with an energy dispersion spectrometer, X-ray diffraction, Raman spectroscopy, and infrared spectra. After graphene formation, the intercalated defects that existed in the GO were removed, and it became crystalline by observing impurity changes and d-spacing. Dye-sensitized solar cells, using reduced graphene as the counter electrode, were fabricated to evaluate the electrolyte activity and charge transport performance. The electrochemical impedance spectra showed that increasing the thermal reduction temperature could achieve faster electron transport and longer electron lifetime, and result in an energy conversion efficiency of approximately 3.4%. Compared to the Pt counter electrode, the low cost of the thermal reduction method suggests that graphene will enjoy a wide range of potential applications in the field of electronic devices.

  17. Characteristics of thermally reduced graphene oxide and applied for dye-sensitized solar cell counter electrode

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Ching-Yuan, E-mail: cyho@cycu.edu.tw [Department of Mechanical Engineering, Chung Yuan Christian University, Chung-Li, Taiwan (China); Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung Yuan Christian University, Chung-Li, Taiwan (China); Wang, Hong-Wen [Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung Yuan Christian University, Chung-Li, Taiwan (China); Department of Chemistry, Chung Yuan Christian University, Chung-Li, Taiwan (China)

    2015-12-01

    Graphical abstract: Experimental process: (1) graphite oxidized to graphene oxide; (2) thermal reduction from graphene oxide to graphene; (3) applying to DSSC counter electrode. - Highlights: • Intercalated defects were eliminated by increasing reduction temperature of GO. • High reduction temperature of tGP has lower resistance, high the electron lifetime. • Higher thermal reduction of GO proposes electrocatalytic properties. • DSSC using tGP{sub 250} as counter electrode has energy conversion efficiency of 3.4%. - Abstract: Graphene oxide (GO) was synthesized from a flake-type of graphite powder, which was then reduced to a few layers of graphene sheets using the thermal reduction method. The surface morphology, phase crystallization, and defect states of the reduced graphene were determined from an electron microscope equipped with an energy dispersion spectrometer, X-ray diffraction, Raman spectroscopy, and infrared spectra. After graphene formation, the intercalated defects that existed in the GO were removed, and it became crystalline by observing impurity changes and d-spacing. Dye-sensitized solar cells, using reduced graphene as the counter electrode, were fabricated to evaluate the electrolyte activity and charge transport performance. The electrochemical impedance spectra showed that increasing the thermal reduction temperature could achieve faster electron transport and longer electron lifetime, and result in an energy conversion efficiency of approximately 3.4%. Compared to the Pt counter electrode, the low cost of the thermal reduction method suggests that graphene will enjoy a wide range of potential applications in the field of electronic devices.

  18. Thermal wet oxidation improves anaerobic biodegradability of raw and digested biowaste

    DEFF Research Database (Denmark)

    Lissens, G.; Thomsen, Anne Belinda; De Baere, L.

    2004-01-01

    yield and digestion kinetics and permitted lignin utilization during a subsequent second digestion. The increase of the specific methane yield for the full-scale biogas plant by applying thermal wet oxidation was 35-40%, showing that there is still a considerable amount of methane that can be harvested...... profits. The objective of this research was to enhance the anaerobic biodegradability and methane yields from different biowastes (food waste, yard waste, and digested biowaste already treated in a full-scale biogas plant (DRANCO, Belgium)) by assessing thermal wet oxidation. The biodegradability...

  19. Measurement of the diffusion length of thermal neutrons in the beryllium oxide

    International Nuclear Information System (INIS)

    Koechlin, J.C.; Martelly, J.; Duggal, V.P.

    1955-01-01

    The diffusion length of thermal neutrons in the beryllium oxide has been obtained while studying the spatial distribution of the neutrons in a massive parallelepiped of this matter placed before the thermal column of the reactor core of Saclay. The mean density of the beryllium oxide (BeO) is 2,95 gr/cm 3 , the mean density of the massif is 2,92 gr/cm 3 . The value of the diffusion length, deducted of the done measures, is: L = 32,7 ± 0,5 cm (likely gap). Some remarks are formulated about the influence of the spectral distribution of the neutrons flux used. (authors) [fr

  20. Analysis of the temperature dependence of the thermal conductivity of insulating single crystal oxides

    Directory of Open Access Journals (Sweden)

    E. Langenberg

    2016-10-01

    Full Text Available The temperature dependence of the thermal conductivity of 27 different single crystal oxides is reported from ≈20 K to 350 K. These crystals have been selected among the most common substrates for growing epitaxial thin-film oxides, spanning over a range of lattice parameters from ≈3.7 Å to ≈12.5 Å. Different contributions to the phonon relaxation time are discussed on the basis of the Debye model. This work provides a database for the selection of appropriate substrates for thin-film growth according to their desired thermal properties, for applications in which heat management is important.

  1. Preparation of polyvinyl alcohol graphene oxide phosphonate film and research of thermal stability and mechanical properties.

    Science.gov (United States)

    Li, Jihui; Song, Yunna; Ma, Zheng; Li, Ning; Niu, Shuai; Li, Yongshen

    2018-05-01

    In this article, flake graphite, nitric acid, peroxyacetic acid and phosphoric acid are used to prepare graphene oxide phosphonic and phosphinic acids (GOPAs), and GOPAs and polyvinyl alcohol (PVA) are used to synthesize polyvinyl alcohol graphene oxide phosphonate and phosphinate (PVAGOPs) in the case of faint acidity and ultrasound irradiation, and PVAGOPs are used to fabricate PVAGOPs film, and the structure and morphology of GOPAs, PVAGOPs and PVAGOPs film are characterized, and the thermal stability and mechanical properties of PVAGOPs film are investigated. Based on these, it has been proved that GOPAs consist of graphene oxide phosphonic acid and graphene oxide phosphinic acid, and there are CP covalent bonds between them, and PVAGOPs are composed of GOPAs and PVA, and there are six-member lactone rings between GOPAs and PVA, and the thermal stability and mechanical properties of PVAGOPs film are improved effectively. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Iron Oxide Films Prepared by Rapid Thermal Processing for Solar Energy Conversion.

    Science.gov (United States)

    Wickman, B; Bastos Fanta, A; Burrows, A; Hellman, A; Wagner, J B; Iandolo, B

    2017-01-16

    Hematite is a promising and extensively investigated material for various photoelectrochemical (PEC) processes for energy conversion and storage, in particular for oxidation reactions. Thermal treatments during synthesis of hematite are found to affect the performance of hematite electrodes considerably. Herein, we present hematite thin films fabricated via one-step oxidation of Fe by rapid thermal processing (RTP). In particular, we investigate the effect of oxidation temperature on the PEC properties of hematite. Films prepared at 750 °C show the highest activity towards water oxidation. These films show the largest average grain size and the highest charge carrier density, as determined from electron microscopy and impedance spectroscopy analysis. We believe that the fast processing enabled by RTP makes this technique a preferred method for investigation of novel materials and architectures, potentially also on nanostructured electrodes, where retaining high surface area is crucial to maximize performance.

  3. Potential Health Implications of the Consumption of Thermally-Oxidized Cooking Oils – a Review

    Directory of Open Access Journals (Sweden)

    Falade Ayodeji Osmund

    2017-06-01

    Full Text Available Cooking oils are an integral part of a human diet as they are used in almost all types of culinary practices. They serve as sources of lipids with a significant nutritive value and health benefits which can be attributed to their fatty acid compositions and biological antioxidants. However, cooking oils are usually subjected to thermal oxidation which occurs when fresh cooking oil is heated at high temperatures during various food preparations. Repeated use of cooking oils in the commercial food industry is also common to maximize profit. Thermal oxidation of edible oils had since attracted great attention of nutritionist and researchers given the deteriorative effect such as generation of very cytotoxic compounds, loss of carotenoid, phenolics and vitamins thus reducing the overall antioxidant properties of the oils. Furthermore, several in vivo studies had suggested that consumption of thermally-oxidized cooking oils might not be healthy as it might negatively influence the lipid profile (increased low density lipoprotein (LDL, decreased high density lipoprotein (HDL and elevated cholesterol level, haematological system (alteration in concentration of heamoglobin (Hb, packed cell volume (PCV, white blood cell (WBC count, neutrophil and lymphocyte counts, kidney function, and induce lipid peroxidation and oxidative stress which have been associated with the pathogenesis of various degenerative diseases. Therefore, thermal oxidation seems not to provide any health benefit, as it deteriorates cooking oils and the consumption of the oils may predispose consumers to various disease conditions that may ensue from free radical generation, thereby having deleterious effect on human health.

  4. The influence of natural tocopherols during thermal oxidation of refined and partially hydrogenated soybean oils

    OpenAIRE

    Barrera-Arellano, D.; Dobarganes, M. C.; Steel, C. J.

    2005-01-01

    Samples of refined and partially hydrogenated soybean oils, with iodine values between 60 and 130, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C (during) for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds) and tocopherols. The relation of iodine value to the formation of dimers and polymers and the role of originally present tocopherols in the ...

  5. Thermal oxidation of Zr–Cu–Al–Ni amorphous metal thin films

    Energy Technology Data Exchange (ETDEWEB)

    Oleksak, R.P.; Hostetler, E.B.; Flynn, B.T. [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331 (United States); McGlone, J.M.; Landau, N.P.; Wager, J.F. [School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, OR 97331 (United States); Stickle, W.F. [Hewlett-Packard Company, Corvallis, OR 97333 (United States); Herman, G.S., E-mail: greg.herman@oregonstate.edu [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331 (United States)

    2015-11-30

    The initial stages of thermal oxidation for Zr–Cu–Al–Ni amorphous metal thin films were investigated using X-ray photoelectron spectroscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The as-deposited films had oxygen incorporated during sputter deposition, which helped to stabilize the amorphous phase. After annealing in air at 300 °C for short times (5 min) this oxygen was found to segregate to the surface or buried interface. Annealing at 300 °C for longer times leads to significant composition variation in both vertical and lateral directions, and formation of a surface oxide layer that consists primarily of Zr and Al oxides. Surface oxide formation was initially limited by back-diffusion of Cu and Ni (< 30 min), and then by outward diffusion of Zr (> 30 min). The oxidation properties are largely consistent with previous observations of Zr–Cu–Al–Ni metallic glasses, however some discrepancies were observed which could be explained by the unique sample geometry of the amorphous metal thin films. - Highlights: • Thermal oxidation of amorphous Zr–Cu–Al–Ni thin films was investigated. • Significant short-range inhomogeneities were observed in the amorphous films. • An accumulation of Cu and Ni occurs at the oxide/metal interface. • Diffusion of Zr was found to limit oxide film growth.

  6. Thermal expansion and thermal conductivity of (Th,U)O{sub 2} mixed oxides: A molecular dynamics and experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, P.S., E-mail: psghosh@barc.gov.in [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Somayajulu, P.S. [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Krishnan, K. [Fuel Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Pathak, N. [Radio Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Arya, A.; Dey, G.K. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2015-11-25

    Thermal expansion and thermal conductivity of ThO{sub 2} and (Th,U)O{sub 2} mixed oxides (MOX) have been investigated by using molecular dynamics (MD) simulation and experimental study. MD simulation have been performed to determine lattice thermal expansion of Th{sub 1−x}U{sub x}O{sub 2} (x = 0 to 0.3125) solid-solutions in the temperature range of 300–3000 K using a combination of Coulomb-Buckingham-Morse and many-body potential model with partial ionic charges. Special quasi-random structures were employed to establish solid-solution configurations. Experimental verification of the lattice thermal expansion behavior is carried out on polycrystalline sample of ThO{sub 2} -x wt.% UO{sub 2} (x = 0, 6, 13, 25 and 30) MOX from room temperature to 1273 K in vacuum using high temperature X-ray diffraction (HT-XRD). Our combined MD simulations and HT-XRD measurements indicate that incorporation of UO{sub 2} in ThO{sub 2} systematically increases coefficient of thermal expansion but the rate of increase is higher in low UO{sub 2} composition range (≤13 wt.%). A comparative evaluation of the thermal properties of ThO{sub 2}-6wt.% UO{sub 2} pellets prepared by coated agglomerate pelletization (CAP) process and powder metallurgy routes (sintered in Ar-8%H{sub 2} atmosphere) have been performed with respect to micro-inhomogeneity, porosity, O/M and trace impurities. The thermal conductivity of ThO{sub 2} and ThO{sub 2}-6 wt.% UO{sub 2} calculated under equilibrium condition by Green–Kubo formalism show good agreement with our experimental measurements. - Highlights: • Thermal expansions of ThO{sub 2} and ThO{sub 2}-6,13,25 and 30 wt.% UO{sub 2} are measured by HT-XRD. • MD calculated lattice thermal expansion of Th{sub 1−x}U{sub x}O{sub 2} (0 ≤ x ≤ 0.3125) between 300 and 3000 K. • Comparative evaluation of thermal properties of ThO{sub 2}-6wt.% UO{sub 2} (CAP and POP pellets). • Evaluation of micro-inhomogeneity, porosity, O/M and trace impurities of

  7. High aspect ratio silicon nanomoulds for UV embossing fabricated by directional thermal oxidation using an oxidation mask

    International Nuclear Information System (INIS)

    Chen, L Q; Chan-Park, Mary B; Yan, Y H; Zhang Qing; Li, C M; Zhang Jun

    2007-01-01

    Nanomoulding is simple and economical but moulds with nanoscale features are usually prohibitively expensive to fabricate because nanolithographic techniques are mostly serial and time-consuming for large-area patterning. This paper describes a novel, simple and inexpensive parallel technique for fabricating nanoscale pattern moulds by silicon etching followed by thermal oxidation. The mask pattern can be made by direct photolithography or photolithography followed by metal overetching for submicron- and nanoscale features, respectively. To successfully make nanoscale channels having a post-oxidation cross-sectional shape similar to that of the original channel, an oxidation mask to promote unidirectional (specifically horizontal) oxide growth is found to be essential. A silicon nitride or metal mask layer prevents vertical oxidation of the Si directly beneath it. Without this mask, rectangular channels become smaller but are V-shaped after oxidation. By controlling the silicon etch depth and oxidation time, moulds with high aspect ratio channels having widths ranging from 500 to 50 nm and smaller can be obtained. The nanomould, when passivated with a Teflon-like layer, can be used for first-generation replication using ultraviolet (UV) nanoembossing and second-generation replication in other materials, such as polydimethylsiloxane (PDMS). The PDMS stamp, which was subsequently coated with Au, was used for transfer printing of Au electrodes with a 600 nm gap which will find applications in plastics nanoelectronics

  8. Desarrollo de variedades tropicales de soya para el consumo humano

    Directory of Open Access Journals (Sweden)

    Enrique Villalobos

    2000-01-01

    Full Text Available Se desarrollaron líneas de soya (Glycine max L. Merr. con semillas sin las lipoxigenasas 2 y 3 y con adaptación a condiciones tropicales fueron desarrolladas por el Centro de Investigaciones en Granos y Semillas, de la Universidad de Costa Rica. Estas líneas se obtuvieron del cruce de plantas F3 seleccionadas del cruce de ‘Kanto-101’ X ‘IAC- 8’ con plantas F2 seleccionadas del cruce de ‘Padre’ X ‘Duocrop’. Kanto-101 es una variedad japonesa que se usó como donadora de los genes lox2 y lox3, que inhiben la síntesis de las lipoxigenasas 2 y 3 en la semilla de soya. La eliminación de las lipoxigenasas 2 y 3 mejora considerablemente las características sensoriales de la leche de soya. La variedad Padre, se usó como donadora de los genes que retardan la floración en condiciones de día corto. Las líneas F11 CIGRAS-34, 47, 51 y 57 (lox2,lox3 derivadas del cruzamiento doble, mostraron un buen comportamiento agronómico cuando se compararon en tres localidades con las variedades CIGRAS-06 y 10 (Lox, previamente liberadas por su alta productividad. El uso del cultivar Padre, portador de los genes que retardan la floración en condiciones de día corto, en los programas de mejoramiento genético de la soya en el trópico, mostró su gran potencial al generar materiales tardíos y con buena adaptación. Los materiales sin lipoxigenasas en la semilla alcanzan un mejor precio en el mercado internacional y son una buena alternativa para la exportación a países donde la soya es parte importante de la dieta humana

  9. Kinetics of switch grass pellet thermal decomposition under inert and oxidizing atmospheres.

    Science.gov (United States)

    Chandrasekaran, Sriraam R; Hopke, Philip K

    2012-12-01

    Grass pellets are a renewable resource that have energy content similar to that of wood. However, the higher ash and chlorine content affects combustion. Thermal degradation analysis of a fuel is useful in developing effective combustion. Thermogravimetric analysis (TGA) of the thermal degradation of grass pellets under inert (nitrogen) and oxidizing (air) atmospheres was conducted. Non-isothermal conditions were employed with 4 different heating rates. Kinetic parameters (activation energy and pre-exponential factors) were estimated using the iso-conversional method. Both pyrolysis and oxidative atmospheric thermal degradation exhibited two major loss process: volatilization of cellulose, hemicelluloses and lignin and burning or slow oxidation of the residual char. The activation energy and pre-exponential factors were high for the oxidizing environment. During pyrolysis, major decomposition occurred with 40% to 75% conversion of the mass to gas with an activation energy of 314 kJ/mol. In air the decomposition occurred with 30% to 55% conversion with an activation energy of 556 kJ/mol. There was a substantial effect of heating rate on mass loss and mass loss rate. The TG shifted to higher temperature ranges on increasing the heating rate. In both pyrolyzing and oxidizing conditions, average combustion and devolatilization rates increased. Enhanced combustion takes place with higher activation energy in oxidizing atmosphere compared to the inert atmosphere due to presence of air. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. STEP wastewater treatment: a solar thermal electrochemical process for pollutant oxidation.

    Science.gov (United States)

    Wang, Baohui; Wu, Hongjun; Zhang, Guoxue; Licht, Stuart

    2012-10-01

    A solar thermal electrochemical production (STEP) pathway was established to utilize solar energy to drive useful chemical processes. In this paper, we use experimental chemistry for efficient STEP wastewater treatment, and suggest a theory based on the decreasing stability of organic pollutants (hydrocarbon oxidation potentials) with increasing temperature. Exemplified by the solar thermal electrochemical oxidation of phenol, the fundamental model and experimental system components of this process outline a general method for the oxidation of environmentally stable organic pollutants into carbon dioxide, which is easily removed. Using thermodynamic calculations we show a sharply decreasing phenol oxidation potential with increasing temperature. The experimental results demonstrate that this increased temperature can be supplied by solar thermal heating. In combination this drives electrochemical phenol removal with enhanced oxidation efficiency through (i) a thermodynamically driven decrease in the energy needed to fuel the process and (ii) improved kinetics to sustain high rates of phenol oxidation at low electrochemical overpotential. The STEP wastewater treatment process is synergistic in that it is performed with higher efficiency than either electrochemical or photovoltaic conversion process acting alone. STEP is a green, efficient, safe, and sustainable process for organic wastewater treatment driven solely by solar energy. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Tunable plasmonic resonance of gallium nanoparticles by thermal oxidation at low temperaturas

    Science.gov (United States)

    Catalán-Gómez, S.; Redondo-Cubero, A.; Palomares, F. J.; Nucciarelli, F.; Pau, J. L.

    2017-10-01

    The effect of the oxidation of gallium nanoparticles (Ga NPs) on their plasmonic properties is investigated. Discrete dipole approximation has been used to study the wavelength of the out-of-plane localized surface plasmon resonance in hemispherical Ga NPs, deposited on silicon substrates, with oxide shell (Ga2O3) of different thickness. Thermal oxidation treatments, varying temperature and time, were carried out in order to increase experimentally the Ga2O3 shell thickness in the NPs. The optical, structural and chemical properties of the oxidized NPs have been studied by spectroscopic ellipsometry, scanning electron microscopy, grazing incidence x-ray diffraction and x-ray photoelectron spectroscopy. A clear redshift of the peak wavelength is observed, barely affecting the intensity of the plasmon resonance. A controllable increase of the Ga2O3 thickness as a consequence of the thermal annealing is achieved. In addition, simulations together with ellipsometry results have been used to determine the oxidation rate, whose kinetics is governed by a logarithmic dependence. These results support the tunable properties of the plasmon resonance wavelength in Ga NPs by thermal oxidation at low temperatures without significant reduction of the plasmon resonance intensity.

  12. Effect of raw soya bean particle size on productive performance and digestion of dairy cows.

    Science.gov (United States)

    Naves, A B; Freitas Júnior, J E; Barletta, R V; Gandra, J R; Calomeni, G D; Gardinal, R; Takiya, C S; Vendramini, T H A; Mingoti, R D; Rennó, F P

    2016-08-01

    Differing soya bean particle sizes may affect productive performance and ruminal fermentation due to the level of fatty acid (FA) exposure of the cotyledon in soya bean grain and because the protein in small particles is more rapidly degraded than the protein in large particles, which influence ruminal fibre digestion and the amounts of ruminally undegradable nutrients. The objective of this experiment was to investigate the effects of raw soya bean particle size on productive performance, digestion and milk FA profile of dairy cows. Twelve Holstein cows were assigned to three 4 × 4 Latin squares with 21-day periods. At the start of the experiment, cows were 121 days in milk (DIM) and yielded 30.2 kg/day of milk. Cows were fed 4 diets: (i) control diet (CO), without raw soya bean; (ii) whole raw soya bean (WRS); (iii) cracked raw soya bean in Wiley mill 4-mm screen (CS4); and (iv) cracked raw soya bean in Wiley mill 2-mm screen (CS2). The inclusion of soya beans (whole or cracked) was 200 g/kg on dry matter (DM) basis and partially replaced ground corn and soya bean meal. Uncorrected milk yield and composition were not influenced by experimental diets; however, fat-corrected milk (FCM) decreased when cows were fed soya bean treatments. Soya bean diets increased the intake of ether extract (EE) and net energy of lactation (NEL ), and decreased the intake of DM and non-fibre carbohydrate (NFC). Ruminal propionate concentration was lower in cows fed WRS than cows fed CS2 or CS4. Cows fed cracked raw soya bean presented lower nitrogen in faeces than cows fed WRS. The milk of cows fed WRS, CS2 and CS4 presented higher unsaturated FA than cows fed CO. The addition of raw soya bean in cow diets, regardless of the particle size, did not impair uncorrected milk yield and nutrient digestion, and increased the concentration of unsaturated FA in milk. Cows fed cracked raw soya bean presented similar productive performance to cows fed whole raw soya bean. Journal of

  13. Graphene oxide immobilized enzymes show high thermal and solvent stability

    Czech Academy of Sciences Publication Activity Database

    Hermanová, S.; Zarevúcka, Marie; Bouša, D.; Pumera, M.; Sofer, Z.

    2015-01-01

    Roč. 7, č. 13 (2015), s. 5852-5858 ISSN 2040-3364 R&D Projects: GA ČR(CZ) GA15-09001S Grant - others:GA AV ČR(CZ) M200551203 Institutional support : RVO:61388963 Keywords : graphene oxide * lipase * immobilization Subject RIV: CC - Organic Chemistry Impact factor: 7.760, year: 2015 http://pubs.rsc.org/en/content/articlepdf/2015/nr/c5nr00438a

  14. Vanadium oxide monolayer catalysts. I. Preparation, characterization, and thermal stability

    NARCIS (Netherlands)

    Roozeboom, F.; Fransen, T.; Mars, P.; Gellings, P.J.

    1979-01-01

    Vanadium oxide catalysts of the monolayer type have been prepared by means of chemisorption of vanadate(V)-anions from aqueous solutions and by chemisorption of gaseous V2O3(OH)4. Using Al2O3, Cr2O3, TiO2, CeO2 and ZrO2, catalysts with an approximately complete monomolecular layer of vanadium(V)

  15. Functionalization of cotton fabrics through thermal reduction of graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Guangming; Xu, Zhenglin; Yang, Mengyun [Wuhan Textile University, Wuhan 430073 (China); Tang, Bin, E-mail: bin.tang@deakin.edu.au [Wuhan Textile University, Wuhan 430073 (China); Deakin University, Geelong, Institute for Frontier Materials (Australia); Wang, Xungai [Wuhan Textile University, Wuhan 430073 (China); Deakin University, Geelong, Institute for Frontier Materials (Australia)

    2017-01-30

    Highlights: • Graphene oxide (GO) is in-situ reduced on cotton by heat under nitrogen protection. • The incorporation of reduced GO endowed fabrics with good electrical conductivity. • Repeated bending and washing do not change obviously the electrical conductivity. • The RGO/cotton fabrics show significant UV-blocking and hydrophobic properties. - Abstract: Graphene oxide (GO) was in-situ reduced on cotton fabrics by a simple heat treatment, which endowed cotton fabrics with multi-functions. GO was coated on the surface of cotton fabric through a conventional “dip and dry” approach. Reduced graphene oxide (RGO) was obtained from GO in the presence of cotton by heating under the protection of nitrogen. Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and scanning electron microscopy were employed to characterize the complexes of RGO and cotton (RGO/cotton). The RGO/cotton fabrics showed good electrical conductivity, surface hydrophobicity and ultraviolet (UV) protection properties. These properties did not deteriorate significantly after repeated fabric bending and washing.

  16. A Novel Solid-State Thermal Rectifier Based On Reduced Graphene Oxide

    Science.gov (United States)

    Tian, He; Xie, Dan; Yang, Yi; Ren, Tian-Ling; Zhang, Gang; Wang, Yu-Feng; Zhou, Chang-Jian; Peng, Ping-Gang; Wang, Li-Gang; Liu, Li-Tian

    2012-07-01

    Recently, manipulating heat transport by phononic devices has received significant attention, in which phonon - a heat pulse through lattice, is used to carry energy. In addition to heat control, the thermal devices might also have broad applications in the renewable energy engineering, such as thermoelectric energy harvesting. Elementary phononic devices such as diode, transistor and logic devices have been theoretically proposed. In this work, we experimentally create a macroscopic scale thermal rectifier based on reduced graphene oxide. Obvious thermal rectification ratio up to 1.21 under 12 K temperature bias has been observed. Moreover, this ratio can be enhanced further by increasing the asymmetric ratio. Collectively, our results raise the exciting prospect that the realization of macroscopic phononic device with large-area graphene based materials is technologically feasible, which may open up important applications in thermal circuits and thermal management.

  17. Growth of zinc oxide nanoflowers by thermal evaporation method

    International Nuclear Information System (INIS)

    Abdulgafour, H.I.; Hassan, Z.; Al-Hardan, N.; Yam, F.K.

    2010-01-01

    An alternative method for site-selective growth of ZnO nanostructures that does not use an Au catalyst or a ZnO thin-film seed layer is presented. Well-aligned ZnO nanoflower structure arrays were directly fabricated on silicon substrates through zinc powder evaporation, which uses a simple thermal evaporation method without a catalyst. The collected ZnO nanoflowers were then characterized through X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical properties of these nanostructured materials are also discussed.

  18. Highly defective oxides as sinter resistant thermal barrier coating

    Science.gov (United States)

    Subramanian, Ramesh

    2005-08-16

    A thermal barrier coating material formed of a highly defective cubic matrix structure having a concentration of a stabilizer sufficiently high that the oxygen vacancies created by the stabilizer interact within the matrix to form multi-vacancies, thereby improving the sintering resistance of the material. The concentration of stabilizer within the cubic matrix structure is greater than that concentration of stabilizer necessary to give the matrix a peak ionic conductivity value. The concentration of stabilizer may be at least 30 wt. %. Embodiments include a cubic matrix of zirconia stabilized by at least 30-50 wt. % yttria, and a cubic matrix of hafnia stabilized by at least 30-50 wt. % gadolinia.

  19. Modification of graphite structure by irradiation, revealed by thermal oxidation. Examination by electronic microscopy

    International Nuclear Information System (INIS)

    Rouaud, Michel

    1969-01-01

    Based on the analysis of images obtained by electronic microscopy, this document reports the comparative study of the action of neutrons on three different graphites: a natural one (Ticonderoga) and two pyrolytic ones (Carbone-Lorraine and Raytheon). The approach is based on the modification of features of thermal oxidation of graphites by dry air after irradiation. Different corrosion features are identified. The author states that there seems to be a relationship between the number and shape of these features, and defects existing on the irradiated graphite before oxidation. For low doses, the feature aspect varies with depth at which oxidation occurs. For higher doses, the aspect remains the same [fr

  20. Thermal degradation of poly (dimethylphenylsiloxane) (PDMPS) in vacuum under the influence of oxide

    International Nuclear Information System (INIS)

    Nakhapetyan, R.A.; Kharitonov, N.P.; Ostrovskii, V.V.

    1985-01-01

    The authors studied the influence of oxides (MgO, SiO 2 , Al 2 O 3 , Fe 2 O 3 , CoO, V 2 O 5 , Cr 2 O 3 , ZrO 2 , CdO, Ce 2 O 3 ) on thermal degradation of polydimethylsiloxane (PDMPS) in vacuum in the temperature range 20-300 degrees. The compositions were prepared by mixing 50% of a toluene solution of PDMPS with 25 mass % of oxide on the dry weight of PDMPS in a 125-cm 3 jasper drum. The oxides studied interact with PDMPS in the temperature range 20-300 0 . This is reflected in variations of the ratios of the yields of volatile degradation products. Increase of the yields of D 3 , D 4 , and D 5 cyclodimethylsiloxanes is caused by water absorbed on the oxide surfaces, while increase of the benzene yield is attributable to the presence of the hydroxyl layers on the oxides. It can be determined from the relation between D 4 and D 3 whether hydrolysis or thermal degradation predominates up to 3004 0 . The authors also conclude that the boundary of intensive hydrolysis of PDMPS shifts along the temperature scale in accordance with the nature of the oxide. The nature of the oxide has a stronger influence on the delta/D 3 ratio

  1. 40 CFR 721.10056 - Benzenemethanaminium, N-(3-aminopropyl)-N,N-dimethyl-, N-soya acyl derivs., chlorides.

    Science.gov (United States)

    2010-07-01

    ...)-N,N-dimethyl-, N-soya acyl derivs., chlorides. 721.10056 Section 721.10056 Protection of Environment...-aminopropyl)-N,N-dimethyl-, N-soya acyl derivs., chlorides. (a) Chemical substance and significant new uses...-dimethyl-, N-soya acyl derivs., chlorides (PMN P-03-47; CAS No. 90194-13-1) is subject to reporting under...

  2. 40 CFR 721.7270 - 1-propanaminium, 3-amino-, N,N,N-trimethyl-N-soya acyl derivs., chloride.

    Science.gov (United States)

    2010-07-01

    ...-trimethyl-N-soya acyl derivs., chloride. 721.7270 Section 721.7270 Protection of Environment ENVIRONMENTAL...-soya acyl derivs., chloride. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1-propanaminium, 3-amino-, N,N,N-trimethyl-N-soya acyl derivs...

  3. Inability to detect significant absorption of immunoreactive soya protein in healthy adults may be relevant to its weak allergenicity

    DEFF Research Database (Denmark)

    Lund, Cecilia M; Dirks, Christina G; Pedersen, Mona H

    2013-01-01

    ABSTRACT: Soya and peanut are botanically closely related and share cross-reacting antigens, but compared to soya, peanut allergy has a higher prevalence with more severe allergic reactions. Furthermore, the threshold dose for eliciting reactions is higher for soya. A difference in undigested...

  4. Adhesion properties and stability to thermal oxidation of irradiated copolymers of ethylene with vinyl acetate

    International Nuclear Information System (INIS)

    Ovechkina, G.I.; Soboleva, N.S.; Naumkina, S.I.; Ovechkin, P.L.; Leshchenko, S.S.; Finkel', Eh.Eh.; Karpov, V.L.

    1981-01-01

    Effect of gamma radiation on adhesion strength and stability to thermal oxidation of copolymers of ethylene with vinyl acetate of different composition is considered. Polyetiylene, PVC-plasticized substance copper are used as substrates. Optimum radiation doses for copolymers of different composition are determined [ru

  5. Differential scanning calorimetry thermal properties and oxidative stability indices of microwave heated extra virgin olive oils.

    Science.gov (United States)

    Chiavaro, Emma; Rodriguez-Estrada, Maria Teresa; Bendini, Alessandra; Rinaldi, Massimiliano; Cerretani, Lorenzo

    2011-01-30

    The use of differential scanning calorimetry (DSC) for assessing the deterioration effect of microwave heating on vegetable oils, and on olive oils in particular, has been partially explored in literature. The aim of this work was to evaluate the potential of DSC to discriminate among microwaved extra virgin olive oils (EvOo from different olive cultivar and origin), according to changes on thermal properties (upon cooling and heating) and traditional oxidative stability indices (peroxide, p-anisidine and TOTOX values). An elevated value of lipid oxidation was reached by the most unsaturated EvOo sample (9.5% of linoleic acid) at 6 min of microwave treatment. Free acidity significantly increased (0.42%) only for the oil sample with the highest water content (874 mg kg(-1) oil) at the longest time of treatment. Crystallisation enthalpies significantly decreased and the major exothermic peak shifted towards lower temperature, leading to enlargement of the transition range in all samples due to the formation of weak and mixed crystals among triacylglycerols and lipid degradation products. On the contrary, thermal properties upon heating appeared to similarly vary among samples. The analysis of DSC thermal properties upon cooling seemed to clearly discriminate among different EvOo samples after microwaving. The relation between changes of thermal properties and oxidation parameters should be further studied using additional oxidative stability indices on a larger set of oil samples, due to the complexity of EvOo composition. 2010 Society of Chemical Industry.

  6. The effect of K2CO3 on thermal oxidation of cokes and carbonaceous materials

    Czech Academy of Sciences Publication Activity Database

    Vallová, S.; Plevová, Eva; Šugárková, Věra; Hummel, M.

    2013-01-01

    Roč. 5, č. 3 (2013), s. 100-104 ISSN 1804-2058 Institutional support: RVO:68145535 Keywords : coke * K2CO3 * thermal oxidation Subject RIV: CB - Analytical Chemistry, Separation http://paliva.vscht.cz/cz/archiv-clanku/detail/20

  7. Influence of feeding thermally peroxidized soybean oil on oxidative status in growing pigs

    Science.gov (United States)

    The objectives of this study were to determine whether feeding thermally processed peroxidized soybean oil (SO) induces markers of oxidative stress and alters antioxidant status in pig tissue, blood, and urine. Fifty-six barrows (25.3 ± 3.3 kg initial BW) were randomly assigned to dietary treatments...

  8. Double thermal oxidation scheme for the fabrication of SiO2 nanochannels

    DEFF Research Database (Denmark)

    Persson, Karl Fredrik; Thamdrup, Lasse Højlund; Mikkelsen, Morten Bo Lindholm

    2007-01-01

    -of-the-art fabrication techniques, our double thermal oxidation scheme (DTOS) displays improvements with respect to 4 inch waferscale height variation sigma(h) 2500. We test the devices by measuring capillary filling speed in different channel heights, ranging from 14 to 310 nm. These tests reproduce as well as extend...

  9. The effects of Bifidobacteria on the lipid profile and oxidative stress biomarkers of male rats fed thermally oxidized soybean oil.

    Science.gov (United States)

    Awney, Hala A

    2011-08-01

    Over the years, there has been concern about the changes taking place in heated oils and the effects on individuals consuming them. The present study investigated the effects of a diet containing thermally oxidized soybean oil (TO) or TO supplemented with probiotic Bifidobacteria (TO+Pro) on the serum lipid profile and oxidative stress biomarkers of male rats. The data showed several indicators of oil deterioration after thermal processing, including high levels of % free fatty acid (FFA; 15-fold), acid value (AV; 14-fold), peroxide value (8-fold), p-anisidine value (AnV; 39-fold), total oxidation value (TOTOX; 19-fold), thiobarbituric acid-reactive substances (TBARS) value (8.5-fold), and trans-FA (TFA) isomers (2.5-fold) compared to the control. The rats that were fed a diet containing TO showed a significant (p blood serum samples. High levels of TBARS, superoxide dismutase (SOD), and glutathione reductase (GR) activities were also detected in the livers, kidneys, testes, and brains of rats. Interestingly, a diet containing TO+Pro restored all biological parameters to their control values. The present data suggested that Bifidobacteria may ameliorate the serum lipid profile and oxidative stress biomarkers that are generated in animals that are fed a TO diet.

  10. Oxidation behavior of Hf-modified platinum aluminide coatings during thermal cycling

    Directory of Open Access Journals (Sweden)

    Liya Ye

    2018-02-01

    Full Text Available Platinum aluminide coatings with different Hf contents were fabricated by using HfCl4. The oxidation kinetics and the rumpling behavior of oxide scale were investigated. After thermal cycling, the coating with 0.46 wt% Hf showed least weight gain. With the increase of Hf content, rumpling extent of the scale decreased. Meanwhile, HfO2 preferentially formed in the scale resulting in the increase of scale thickness. The oxidation of excessive Hf even caused the spallation of the scale. The results in the present study indicate that although Hf plays an important role in decreasing rumpling extent of TGO, the oxidation of Hf decreases the adhesion of the scale. Keywords: Pt-Al coating, Hf, Oxidation, Rumpling

  11. Growth and process conditions of aligned and patternable films of iron(III) oxide nanowires by thermal oxidation of iron

    International Nuclear Information System (INIS)

    Hiralal, P; Unalan, H E; Amaratunga, G A J; Wijayantha, K G U; Kursumovic, A; MacManus-Driscoll, J L; Jefferson, D

    2008-01-01

    A simple, catalyst-free growth method for vertically aligned, highly crystalline iron oxide (α-Fe 2 O 3 ) wires and needles is reported. Wires are grown by the thermal oxidation of iron foils. Growth properties are studied as a function of temperature, growth time and oxygen partial pressure. The size, morphology and density of the nanostructures can be controlled by varying growth temperature and time. Oxygen partial pressure shows no effect on the morphology of resulting nanostructures, although the oxide thickness increases with oxygen partial pressure. Additionally, by using sputtered iron films, the possibility of growth and patterning on a range of different substrates is demonstrated. Growth conditions can be adapted to less tolerant substrates by using lower temperatures and longer growth time. The results provide some insight into the mechanism of growth.

  12. Production of peptone from soya beans ( Glycine max L merr ) and ...

    African Journals Online (AJOL)

    Production of peptone from soya beans (Glycine max L merr) and African locust beans (Parkia biglobosa). RE Uzeh, SO Akinola, SOA Olatope. Abstract. Peptone was produced from soya beans and African locust beans. The produced peptones were evaluated as component of microbiological media for the growth of some ...

  13. SO2 oxidation catalyst model systems characterized by thermal methods

    DEFF Research Database (Denmark)

    Hatem, G; Eriksen, Kim Michael; Gaune-Escard, M

    2002-01-01

    The molten salts M2S2O7 and MHSO4, the binary molten salt Systems M2S2O7-MHSO4 and the molten salt-gas systems M2S2O7 V2O5 and M2S2O7-M2SO4 V2O5 (M = Na, K, Rb, Cs) in O-2, SO2 and At atmospheres have been investigated by thermal methods like calorimetry, Differential Enthalpic Analysis (DEA......) and Differential Scanning Calorimetry (DSC). Fundamental thermodynamic data like temperatures and molar heats of solid-solid transition and fusion, phase diagrams, heat capacities of solids and liquids, heat of mixing and heats of complex formation have been obtained and the results are discussed in relation...

  14. Graphene oxide-loaded shortening as an environmentally friendly heat transfer fluid with high thermal conductivity

    Directory of Open Access Journals (Sweden)

    Vongsetskul Thammasit

    2017-01-01

    Full Text Available Graphene oxide-loaded shortening (GOS, an environmentally friendly heat transfer fluid with high thermal conductivity, was successfully prepared by mixing graphene oxide (GO with a shortening. Scanning electron microscopy revealed that GO particles, prepared by the modified Hummer’s method, dispersed well in the shortening. In addition, the latent heat of GOS decreased while their viscosity and thermal conductivity increased with increasing the amount of loaded GO. The thermal conductivity of the GOS with 4% GO was higher than that of pure shortening of ca. three times, from 0.1751 to 0.6022 W/mK, and increased with increasing temperature. The GOS started to be degraded at ca. 360°C. After being heated and cooled at 100°C for 100 cycles, its viscosity slightly decreased and no chemical degradation was observed. Therefore, the prepared GOS is potentially used as environmentally friendly heat transfer fluid at high temperature.

  15. Low-Thermal-Conductivity Pyrochlore Oxide Materials Developed for Advanced Thermal Barrier Coatings

    Science.gov (United States)

    Bansal, Narottam P.; Zhu, Dong-Ming

    2005-01-01

    When turbine engines operate at higher temperatures, they consume less fuel, have higher efficiencies, and have lower emissions. The upper-use temperatures of the base materials (superalloys, silicon-based ceramics, etc.) used for the hot-section components of turbine engines are limited by the physical, mechanical, and corrosion characteristics of these materials. Thermal barrier coatings (TBCs) are applied as thin layers on the surfaces of these materials to further increase the operating temperatures. The current state-of-the-art TBC material in commercial use is partially yttria-stabilized zirconia (YSZ), which is applied on engine components by plasma spraying or by electron-beam physical vapor deposition. At temperatures higher than 1000 C, YSZ layers are prone to sintering, which increases thermal conductivity and makes them less effective. The sintered and densified coatings can also reduce thermal stress and strain tolerance, which can reduce the coating s durability significantly. Alternate TBC materials with lower thermal conductivity and better sintering resistance are needed to further increase the operating temperature of turbine engines.

  16. Thermally stimulated iron oxide transformations and magnetic behaviour of cerium dioxide/iron oxide reactive sorbents

    Czech Academy of Sciences Publication Activity Database

    Luňáček, J.; Životský, O.; Jirásková, Yvonna; Buršík, Jiří; Janoš, P.

    2016-01-01

    Roč. 120, OCT (2016), s. 295-303 ISSN 1044-5803 R&D Projects: GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : Oxide-nano- composite s * Mössbauer spectroscopy * TEM * Cerium oxide * Magnetic parameters Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.714, year: 2016

  17. A highly sensitive and durable electrical sensor for liquid ethanol using thermally-oxidized mesoporous silicon

    Science.gov (United States)

    Harraz, Farid A.; Ismail, Adel A.; Al-Sayari, S. A.; Al-Hajry, A.; Al-Assiri, M. S.

    2016-12-01

    A capacitive detection of liquid ethanol using reactive, thermally oxidized films constructed from electrochemically synthesized porous silicon (PSi) is demonstrated. The sensor elements are fabricated as meso-PSi (pore sizes hydrophobic PSi surface exhibited almost a half sensitivity of the thermal oxide sensor. The response to water is achieved only at the oxidized surface and found to be ∼one quarter of the ethanol sensitivity, dependent on parameters such as vapor pressure and surface tension. The capacitance response retains ∼92% of its initial value after continuous nine cyclic runs and the sensors presumably keep long-term stability after three weeks storage, demonstrating excellent durability and storage stability. The observed behavior in current system is likely explained by the interface interaction due to dipole moment effect. The results suggest that the current sensor structure and design can be easily made to produce notably higher sensitivities for reversible detection of various analytes.

  18. The Kinetics Of Ti-1Al-1Mn Alloy Thermal Oxidation And Charcteristic Of Oxide Layer

    Directory of Open Access Journals (Sweden)

    Klimecka-Tatar D.

    2015-06-01

    Full Text Available The main goal of the study was to carry out the treatment of cyclic oxidation of Ti alloy (Ti-1Al-1Mn in air atmosphere. Based on measurements of mass gain of titanium alloy samples (Ti-1Al-1Mn the kinetic oxidation curves during cyclic annealing were determined. The oxidized surface of the titanium alloy was carefully observed with optical microscopy equipment and the geometrical development, shape and surface morphology were defined. The phase composition of the obtained oxide layers on the Ti-alloy with qualitative analysis of the X-ray were defined. Since titanium alloys are among the most widely used metallic materials in dental prosthetics the corrosion measurements in a solution simulating the environment of the oral cavity were carried out. The results confirmed that the used titanium alloy easily covered with oxides layers, which to some extent inhibit the processes of electrochemical corrosion in artificial saliva solution.

  19. Consumption of thermally oxidized palm oil diets alters biochemical indices in rats

    Directory of Open Access Journals (Sweden)

    Ayodeji Osmund Falade

    2015-06-01

    Full Text Available Palm oil is thermally oxidized to increase its palatability and this has been a usual practice in most homes. This study sought to assess the biochemical responses of rats to thermally oxidized palm oil diets. Therefore, Wistar strain albino rats (Rattus norveigicus were fed with fresh palm oil (control and thermally oxidized palm oil (test groups diets and water ad libitum for 30 days. Then, the malondialdehyde (MDA contents and total protein of the plasma and liver were determined. Subsequently, the plasma liver function markers [alanine transaminase (ALT, aspartate transaminase (AST, alkaline phosphatase (ALP, albumin (ALB and total bilirubin (TBIL ] and the lipid profile [triglyceride (TRIG, total cholesterol (T-CHOL, high density lipoprotein (HDL-CHOL and low density lipoprotein (LDL-CHOL ] were assayed. The results of the study revealed that there was a significant decrease (P < 0.05 in the plasma and liver total protein, ALB, TRIG and HDL-CHOL of the test groups when compared with the control. Conversely, there was a significant increase (P < 0.05 in the activities of ALT, AST and ALP, TBIL, T-CHOL, LDL-CHOL and plasma/liver MDA of the test groups when compared with the control. These effects were most pronounced in rats fed with 20 min-thermally oxidized palm oil diet. Hence, consumption of thermally oxidized palm oil diets had deleterious effects on biochemical indices in rats. Therefore, cooking with and/or consumption of palm oil subjected to heat treatment for several long periods of time should be discouraged in our homes as this might have deleterious effects on human health.

  20. High levels of whole raw soya beans in dairy cow diets: digestibility and animal performance.

    Science.gov (United States)

    Barletta, R V; Gandra, J R; Freitas Junior, J E; Verdurico, L C; Mingoti, R D; Bettero, V P; Benevento, B C; Vilela, F G; Rennó, F P

    2016-12-01

    The aim of this study was to evaluate the effects of high levels of whole raw soya beans in the diets of lactating cows. Twelve Holstein dairy cows were used, randomized in three 4 ×  4 balanced and contemporary Latin squares and fed the following diets: (i) control (C), without including whole raw soya beans; (ii) 80 g/kg in DM of whole raw soya beans (G80); (iii) 160 g/kg in DM of whole raw soya beans (G160); and (iv) 240 g/kg in DM of whole raw soya beans (G240). There was significant reduction (p beans in dairy cow diets improves the unsaturated fatty acid profile in milk, and the diets (G80 and G160) led to minor alterations in the digestive processes and animal metabolism. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  1. Standard Test Method for Thermal Oxidative Resistance of Carbon Fibers

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1982-01-01

    1.1 This test method covers the apparatus and procedure for the determination of the weight loss of carbon fibers, exposed to ambient hot air, as a means of characterizing their oxidative resistance. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units which are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard information, see Section 8.

  2. Soya-lecithin in extender improves the freezability and fertility of buffalo (Bubalus bubalis) bull spermatozoa.

    Science.gov (United States)

    Akhter, S; Ansari, M S; Andrabi, S M H; Rakha, B A; Ullah, N; Khalid, M

    2012-10-01

    Egg yolk is routinely used as a cryoprotectant in semen extenders. However, it may contain cryoprotective antagonists, and there are hygienic risks associated with its use. Proteins of plant origin, like soya-lecithin, lack these hazards. The aim of this study was to use soya-lecithin as a cryoprotectant in extender and to investigate its effects on in vitro quality and in vivo fertility of buffalo semen. Semen from three buffalo bulls was frozen in tris-citric extender containing 5.0%, 10% or 15% soya-lecithin or 20% egg yolk. Sperm motility, plasma membrane integrity and viability were assessed post-dilution, pre-freezing and post-thaw. In Post-dilution and pre-freezing, the values for motility, plasma membrane integrity and viability remained higher (p ≤ 0.05) in extenders containing 10% soya-lecithin and control compared with extender containing 5% and 15% soya-lecithin. However, motility, plasma membrane integrity and viability were higher (p soya-lecithin compared with control and extenders containing 5% and 15% soya-lecithin. Semen from two buffalo bulls was frozen in tris-citric extender containing either 10% soya-lecithin or 20% egg yolk. Higher (p soya-lecithin (56%) compared with 20% egg yolk (41.5%). The results suggest that 10% soya-lecithin in extender improves the freezability and fertility of buffalo bull spermatozoa and can be used as an alternate to egg yolk in cryopreservation of buffalo semen. © 2011 Blackwell Verlag GmbH.

  3. Soya and isoflavone intakes associated with reduced risk of oesophageal cancer in north-west China.

    Science.gov (United States)

    Tang, Li; Lee, Andy H; Xu, Fenglian; Zhang, Taotao; Lei, Jun; Binns, Colin W

    2015-01-01

    To ascertain the association between soya consumption, isoflavone intakes and oesophageal cancer risk in remote north-west China, where the incidence of oesophageal cancer is known to be high. Case-control study. Information on habitual consumption of soya foods and soya milk was obtained by personal interview. The intakes of isoflavones were then estimated using the US Department of Agriculture nutrient database. Logistic regression analyses were performed to assess the association between soya consumption, isoflavone intakes and oesophageal cancer risk. Urumqi and Shihezi, Xinjiang Uyghur Autonomous Region, China. Participants were 359 incident oesophageal cancer patients and 380 hospital-based controls. The oesophageal cancer patients consumed significantly less (P soya foods (mean 57·2 (sd 119·0) g/d) and soya milk (mean 18·8 (sd 51·7) ml/d) than the controls (mean 93·3 (sd 121·5) g/d and mean 35·7 (sd 73·0) ml/d). Logistic regression analyses showed an inverse association between intake of soya products and the risk of oesophageal cancer. The adjusted odds were OR = 0·33 (95 % CI 0·22, 0·49) and OR = 0·48 (95 % CI 0·31, 0·74) for consuming at least 97 g of soya foods and 60 ml of soya milk daily (the highest tertiles of consumption), respectively, relative to the lowest tertiles of consumption. Similarly, inverse associations with apparent dose-response relationships were found between isoflavone intakes and oesophageal cancer risk. Habitual consumption of soya products appears to be associated with reduced risk of oesophageal cancer in north-west China.

  4. Calcium incorporation in graphene oxide particles: A morphological, chemical, electrical, and thermal study

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Kelly L.S. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Instituto de Química, Universidade Federal do Rio de Janeiro, Av. Athos da Silveira Ramos, 149, 21941-909 Rio de Janeiro (Brazil); Curti, Raphael V.; Araujo, Joyce R.; Landi, Sandra M.; Ferreira, Erlon H.M.; Neves, Rodrigo S.; Kuznetsov, Alexei; Sena, Lidia A. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Archanjo, Braulio S., E-mail: bsarchanjo@inmetro.gov.br [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Achete, Carlos A. [Instituto Nacional de Metrologia, Qualidade e Tecnologia, Av. Nossa Sra. das Graças, 50, 25250-020 Duque de Caxias (Brazil); Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro (Brazil)

    2016-07-01

    Surface chemical modification and functionalization are common strategies used to provide new properties or functionalities to a material or to enhance existing ones. In this work, graphene oxide prepared using Hummers' method has been chemically modified with calcium ions by immersion in a calcium carbonate solution. Transmission electron microscopy analyses showed that graphene oxide (GO) and calcium incorporated graphene oxide have a morphology similar to an ultra-thin membrane composed of overlapping sheets. X-ray diffraction and Fourier-infrared spectroscopy show that calcium carbonate residue was completely removed by hydrochloric acid washes. Energy dispersive X-ray spectroscopy mapping showed spatially homogeneous calcium in Ca-incorporated graphene oxide sample after HCl washing. This Ca is mainly ionic according to X-ray photoelectron spectroscopy, and its incorporation promoted a small reduction in the graphene oxide structure, corroborated also by four-point probe measurements. A thermal study shows a remarkable increase in the GO stability with the presence of Ca{sup 2+} ions. - Highlights: • Graphene oxide has been chemically modified with Ca ions by immersion in a CaCO{sub 3} solution. • GO–Ca has morphology similar to an ultra-thin membrane composed of overlapping sheets. • CaCO{sub 3} residue was completely removed by acid washes, leaving only ionic calcium. • EDS maps show that Ca incorporation is spatially homogeneous in GO structure. • Thermal analyses show a remarkable increase in GO stability after Ca incorporation.

  5. Thermal durability of OPC pastes admixed with nano iron oxide

    Directory of Open Access Journals (Sweden)

    Ahmed A. Amer

    2015-08-01

    Full Text Available Nanotechnology helps in producing materials with prospective properties, for each field of science (physics, chemistry, bio-science as well as construction materials. Nanoparticles belong to the materials in the field of civil engineering which have a high surface area to provide high chemical reactivity. Some researchers have employed nanoparticles into cementitious materials based on ordinary Portland cement to modify the properties of this system. They have important advantages for the hydration and microstructure of cement paste to increase the rate of hydration and the amount of formed CSH gel. The aim of this work is to investigate the influence of NF on the fire resistance of OPC pastes. The NF was synthesized by thermal decomposition of basic ferric acetate fired at 275, 600 and 800 °C. The crystal size of the prepared NF as previously determined was 14.6, 16.98 and 18.68 nm, respectively. OPC admixed with 1 wt% NF prepared at 275 °C gives the higher fire resistance than those admixed with 2 or 3 wt%. It shows the higher bulk density, compressive strength and lower porosity up to 450 °C than the blank OPC. As the firing temperature of NF increases the fire resistance diminishes.

  6. Thermal bubble inkjet printing of water-based graphene oxide and graphene inks on heated substrate

    Science.gov (United States)

    Huang, Simin; Shen, Ruoxi; Qian, Bo; Li, Lingying; Wang, Wenhao; Lin, Guanghui; Zhang, Xiaofei; Li, Peng; Xie, Yonglin

    2018-04-01

    Stable-jetting water-based graphene oxide (GO) and graphene (GR) inks without any surfactant or stabilizer are prepared from an unstable-jetting water-based starting solvent, with many thermal bubble inkjet satellite drops, by simply increasing the material concentration. The concentration-dependent thermal bubble inkjet droplet generation process is studied in detail. To overcome the low concentration properties of water-based thermal bubble inkjet inks, the substrate temperature is tuned below 60 °C to achieve high-quality print lines. Due to the difference in hydrophilicity and hydrophobicity of the 2D materials, the printed GO lines show a different forming mechanism from that of the GR lines. The printed GO lines are reduced by thermal annealing and by ascorbic acid, respectively. The reduced GO lines exhibit electrical conductivity of the same order of magnitude as that of the GR lines.

  7. Uranium dioxide and beryllium oxide enhanced thermal conductivity nuclear fuel development

    International Nuclear Information System (INIS)

    Andrade, Antonio Santos; Ferreira, Ricardo Alberto Neto

    2007-01-01

    The uranium dioxide is the most used substance as nuclear reactor fuel for presenting many advantages such as: high stability even when it is in contact with water in high temperatures, high fusion point, and high capacity to retain fission products. The conventional fuel is made with ceramic sintered pellets of uranium dioxide stacked inside fuel rods, and presents disadvantages because its low thermal conductivity causes large and dangerous temperature gradients. Besides, the thermal conductivity decreases further as the fuel burns, what limits a pellet operational lifetime. This research developed a new kind of fuel pellets fabricated with uranium dioxide kernels and beryllium oxide filling the empty spaces between them. This fuel has a great advantage because of its higher thermal conductivity in relation to the conventional fuel. Pellets of this kind were produced, and had their thermophysical properties measured by the flash laser method, to compare with the thermal conductivity of the conventional uranium dioxide nuclear fuel. (author) (author)

  8. Desarrollo de variedades tropicales de soya para el consumo humano

    OpenAIRE

    Enrique Villalobos; Fausto Camacho

    2000-01-01

    Se desarrollaron líneas de soya (Glycine max L. Merr.) con semillas sin las lipoxigenasas 2 y 3 y con adaptación a condiciones tropicales fueron desarrolladas por el Centro de Investigaciones en Granos y Semillas, de la Universidad de Costa Rica. Estas líneas se obtuvieron del cruce de plantas F3 seleccionadas del cruce de Kanto-101 X IAC- 8 con plantas F2 seleccionadas del cruce de Padre X Duocrop. Kanto-101 es una variedad japonesa que se usó como donadora de los gen...

  9. Changes in Physical Properties of Graphene Oxide with Thermal Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Pandit, Bhishma; Jo, Chang Hee; Joo, Kwan Seon; Cho, Jaehee [Chonbuk National University, Jeonju (Korea, Republic of)

    2017-08-15

    Reduced graphene oxide (rGO) has attracted significant attention as an easily fabricable two dimensional material. Depending on the oxygen-containing functional groups (OFGs) in an rGO specimen, the optical and electrical properties can vary significantly, directly affecting the performance of devices in which rGO is implemented. Here, we investigated the optical and electrical properties of GO treated with various annealing (reduction) temperatures from 350 to 950 ℃ in H2 ambient. Using diverse characteristic tools, we found that the transmittance, nanoscale domain size, OFGs in GO and rGO, and Schottky barrier height (SBH) measured on n-type GaN are significantly influenced by the annealing temperature. The relative intensity of the defect-induced band in Raman spectroscopy showed a minimum at the annealing temperature of approximately 350 ℃, before the OFGs in rGO showed vigorous changes in relative content. When the domain size of rGO reached a minimum at the annealing temperature of 650 ℃, the SBH of rGO/GaN showed the maximum value of 1.07 eV.

  10. Oxidation and biodegradation of polyethylene films containing pro-oxidantadditives: Synergistic effects of sunlight exposure, thermal aging and fungal biodegradation

    Science.gov (United States)

    Synergistic effects of sunlight exposure, thermal aging and fungal biodegradation on the oxidation and biodegradation of linear low density poly (ethylene) PE-LLD films containing pro-oxidant were examined. To achieve oxidation and degradation, films were first exposed to the sunlight for 93 days du...

  11. Physical and electrical properties of thermal oxidized Sm{sub 2}O{sub 3} gate oxide thin film on Si substrate: Influence of oxidation durations

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Kian Heng; Haseeb, A.S.M.A.; Wong, Yew Hoong, E-mail: yhwong@um.edu.my

    2016-05-01

    Growth of 150 nm Sm{sub 2}O{sub 3} films by sputtered pure samarium metal film on silicon substrates and followed by thermal oxidation process in oxygen ambient at 700 °C through various oxidation durations (5 min, 10 min, 15 min and 20 min) has been carried out. The crystallinity of Sm{sub 2}O{sub 3} film and existence of interfacial layer have been evaluated by X-ray diffraction, Fourier transform infrared and Raman analysis. Crystallite size and microstrain of Sm{sub 2}O{sub 3} were estimated by Williamson–Hall plot analysis. Calculated crystallite size of Sm{sub 2}O{sub 3} from Scherrer equation has similar trend with the value from Williamson–Hall plot. The presence of interfacial layer is supported by composition line scan by energy dispersive X-ray spectroscopy analysis. The surface roughness and surface topography of Sm{sub 2}O{sub 3} film were examined by atomic force microscopy analysis. The electrical characterization revealed that 15 min of oxidation durations with smoothest surface has highest breakdown voltage, lowest leakage current density and highest barrier height value. - Highlights: • Thermal oxidation of sputtered pure metallic Sm in oxygen ambient • Formation of polycrystalline Sm{sub 2}O{sub 3} and semi-polycrystalline interfacial layers • Optimization of oxidation duration of pure metallic Sm in oxygen ambient • Enhanced electrical performance with smooth surface and increased barrier height.

  12. Characterization and dispersibility of improved thermally stable amide functionalized graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Rani, Sumita [Electronic Science Department, Kurukshetra University, Kurukshetra, Haryana 136119 (India); Kumar, Mukesh, E-mail: kumarmukesh@gmail.com [Electronic Science Department, Kurukshetra University, Kurukshetra, Haryana 136119 (India); Kumar, Rajiv [Department of Chemistry, Kurukshetra University, Kurukshetra, Haryana 136119 (India); Kumar, Dinesh; Sharma, Sumit [Electronic Science Department, Kurukshetra University, Kurukshetra, Haryana 136119 (India); Singh, Gulshan [Department of Chemistry, Kurukshetra University, Kurukshetra, Haryana 136119 (India)

    2014-12-15

    Graphical abstract: Improved thermal stability and surface study of amide functionalized graphene oxide. - Highlights: • Amide functionalized graphene oxides (AGOs) were synthesized from aniline, 2-aminothiazole and 2-aminopyrimidine. • Achieved enhancement in thermal stability of AGOs as compare to GO. • AGOs are found to be highly dispersible in water, DMSO and DMF. • Dispersibility is stable for more than two and half months. - Abstract: Amidation of graphene oxide (GO) with aniline, 2-aminothiazole and 2-aminopyrimidine results in the synthesis of amide functionalized graphene oxides (AGOs). Scanning electron microscopy, X-ray diffraction, thermogravimetric analysis (TGA), UV–vis and Raman spectroscopy were used to investigate the properties of AGOs. It was found that, contrary to GO, AGOs are soluble in water, dimethyl sulfoxide, dimethylformamide and can be stabilized for months. TGA of AGOs shows the major weight loss above 670 °C as compared to GO in which significant weight loss occurs near 200 °C. Thus AGOs show strong improvement in thermal properties.

  13. Synthesis and characterization of PEG-iron oxide core-shell composite nanoparticles for thermal therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wydra, Robert J.; Kruse, Anastasia M. [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States); Bae, Younsoo [Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40506 (United States); Anderson, Kimberly W. [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States); Hilt, J. Zach, E-mail: hilt@engr.uky.edu [Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506 (United States)

    2013-12-01

    In this study, core-shell nanoparticles were developed to achieve thermal therapy that can ablate cancer cells in a remotely controlled manner. The core-shell nanoparticles were prepared using atomic transfer radical polymerization (ATRP) to coat iron oxide (Fe{sub 3}O{sub 4}) nanoparticles with a poly(ethylene glycol) (PEG) based polymer shell. The iron oxide core allows for the remote heating of the particles in an alternating magnetic field (AMF). The coating of iron oxide with PEG was verified through Fourier transform infrared spectroscopy and thermal gravimetric analysis. A thermoablation (55 °C) study was performed on A549 lung carcinoma cells exposed to nanoparticles and over a 10 min AMF exposure. The successful thermoablation of A549 demonstrates the potential use of polymer coated particles for thermal therapy. - Highlights: • Utilized atomic transfer radical polymerization (ATRP) to coat iron oxide nanoparticles with PEG • Investigated the surface coating by surface characterization methods • Demonstrated the potential use of nanoparticles for cancer therapy applications.

  14. Thermally oxidized titania nanotubes enhance the corrosion resistance of Ti6Al4V.

    Science.gov (United States)

    Grotberg, John; Hamlekhan, Azhang; Butt, Arman; Patel, Sweetu; Royhman, Dmitry; Shokuhfar, Tolou; Sukotjo, Cortino; Takoudis, Christos; Mathew, Mathew T

    2016-02-01

    The negative impact of in vivo corrosion of metallic biomedical implants remains a complex problem in the medical field. We aimed to determine the effects of electrochemical anodization (60V, 2h) and thermal oxidation (600°C) on the corrosive behavior of Ti-6Al-4V, with serum proteins, at physiological temperature. Anodization produced a mixture of anatase and amorphous TiO2 nanopores and nanotubes, while the annealing process yielded an anatase/rutile mixture of TiO2 nanopores and nanotubes. The surface area was analyzed by the Brunauer-Emmett-Teller method and was estimated to be 3 orders of magnitude higher than that of polished control samples. Corrosion resistance was evaluated on the parameters of open circuit potential, corrosion potential, corrosion current density, passivation current density, polarization resistance and equivalent circuit modeling. Samples both anodized and thermally oxidized exhibited shifts of open circuit potential and corrosion potential in the noble direction, indicating a more stable nanoporous/nanotube layer, as well as lower corrosion current densities and passivation current densities than the smooth control. They also showed increased polarization resistance and diffusion limited charge transfer within the bulk oxide layer. The treatment groups studied can be ordered from greatest corrosion resistance to least as Anodized+Thermally Oxidized > Anodized > Smooth > Thermally Oxidized for the conditions investigated. This study concludes that anodized surface has a potential to prevent long term implant failure due to corrosion in a complex in-vivo environment. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Thermal oxidation of nuclear graphite: A large scale waste treatment option.

    Directory of Open Access Journals (Sweden)

    Alex Theodosiou

    Full Text Available This study has investigated the laboratory scale thermal oxidation of nuclear graphite, as a proof-of-concept for the treatment and decommissioning of reactor cores on a larger industrial scale. If showed to be effective, this technology could have promising international significance with a considerable impact on the nuclear waste management problem currently facing many countries worldwide. The use of thermal treatment of such graphite waste is seen as advantageous since it will decouple the need for an operational Geological Disposal Facility (GDF. Particulate samples of Magnox Reactor Pile Grade-A (PGA graphite, were oxidised in both air and 60% O2, over the temperature range 400-1200°C. Oxidation rates were found to increase with temperature, with a particular rise between 700-800°C, suggesting a change in oxidation mechanism. A second increase in oxidation rate was observed between 1000-1200°C and was found to correspond to a large increase in the CO/CO2 ratio, as confirmed through gas analysis. Increasing the oxidant flow rate gave a linear increase in oxidation rate, up to a certain point, and maximum rates of 23.3 and 69.6 mg / min for air and 60% O2 respectively were achieved at a flow of 250 ml / min and temperature of 1000°C. These promising results show that large-scale thermal treatment could be a potential option for the decommissioning of graphite cores, although the design of the plant would need careful consideration in order to achieve optimum efficiency and throughput.

  16. Ionic Conductance, Thermal and Morphological Behavior of PEO-Graphene Oxide-Salts Composites

    Directory of Open Access Journals (Sweden)

    Mohammad Saleem Khan

    2015-01-01

    Full Text Available Thin films composites of poly(ethylene oxide-graphene oxide were fabricated with and without lithium salts by solvent cast method. The ionic conductivity of these composites was studied at various concentrations of salt polymer-GO complexes and at different temperatures. The effects of temperature and graphene oxide concentration were measured from Arrhenius conductance plots. It is shown that the addition of salts in pure PEO increases conductance many times. The graphene oxide addition has enhanced the conductance approximately 1000 times as compared to that of pure PEO. The activation energies were determined for all the systems which gave higher values for pure PEO and the value decreased with the addition of LiClO4 and LiCl salts and further decreases with the addition of graphene oxide. The composite has also lowered the activation energy values which mean that incorporation of GO in PEO has decreased crystallinity and the amorphous region has increased the local mobility of polymer chains resulting in lower activation energies. SEM analysis shows uniform distribution of GO in polymer matrix. The thermal stability studies reveal that incorporation of GO has somewhat enhanced the thermal stability of the films.

  17. Novel Materials through Non-Hydrolytic Sol-Gel Processing: Negative Thermal Expansion Oxides and Beyond

    Directory of Open Access Journals (Sweden)

    Cora Lind

    2010-04-01

    Full Text Available Low temperature methods have been applied to the synthesis of many advanced materials. Non-hydrolytic sol-gel (NHSG processes offer an elegant route to stable and metastable phases at low temperatures. Excellent atomic level homogeneity gives access to polymorphs that are difficult or impossible to obtain by other methods. The NHSG approach is most commonly applied to the preparation of metal oxides, but can be easily extended to metal sulfides. Exploration of experimental variables allows control over product stoichiometry and crystal structure. This paper reviews the application of NHSG chemistry to the synthesis of negative thermal expansion oxides and selected metal sulfides.

  18. Volatilisation of ruthenium in vitrification. Isothermal calcination studies of 'Magnox' and thermal oxide simulates

    International Nuclear Information System (INIS)

    Cains, P.W.; Hay, D.A.

    1982-12-01

    Ru volatilities have been measured for the static, isothermal calcination of ''Magnox'' and Thermal Oxide HAL's (Highly Active Liquors) at temperatures up to 600 0 C. Model solutions containing Ru, HNO 3 , and nitrates of important individual cations have also been investigated. Experimental design was primarily based on the requirements of rotary calcination process development. The results have been interpreted in terms of a reaction model involving competition between the simple degradation of Ru(NO) complexes to RuO 2 and oxidative decomposition to volatile species (e.g. RuO 4 ). (author)

  19. Towards the development of a sustainable soya bean-based feedstock for aquaculture.

    Science.gov (United States)

    Park, Hyunwoo; Weier, Steven; Razvi, Fareha; Peña, Pamela A; Sims, Neil A; Lowell, Jennica; Hungate, Cory; Kissinger, Karma; Key, Gavin; Fraser, Paul; Napier, Johnathan A; Cahoon, Edgar B; Clemente, Tom E

    2017-02-01

    Soya bean (Glycine max (L.) Merr.) is sought after for both its oil and protein components. Genetic approaches to add value to either component are ongoing efforts in soya bean breeding and molecular biology programmes. The former is the primary vegetable oil consumed in the world. Hence, its primary usage is in direct human consumption. As a means to increase its utility in feed applications, thereby expanding the market of soya bean coproducts, we investigated the simultaneous displacement of marine ingredients in aquafeeds with soya bean-based protein and a high Omega-3 fatty acid soya bean oil, enriched with alpha-linolenic and stearidonic acids, in both steelhead trout (Oncorhynchus mykiss) and Kampachi (Seriola rivoliana). Communicated herein are aquafeed formulations with major reduction in marine ingredients that translates to more total Omega-3 fatty acids in harvested flesh. Building off of these findings, subsequent efforts were directed towards a genetic strategy that would translate to a prototype design of an optimal identity-preserved soya bean-based feedstock for aquaculture, whereby a multigene stack approach for the targeted synthesis of two value-added output traits, eicosapentaenoic acid and the ketocarotenoid, astaxanthin, were introduced into the crop. To this end, the systematic introduction of seven transgenic cassettes into soya bean, and the molecular and phenotypic evaluation of the derived novel events are described. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  20. The Coadministration of Unoxidized and Oxidized Desi Ghee Ameliorates the Toxic Effects of Thermally Oxidized Ghee in Rabbits

    Directory of Open Access Journals (Sweden)

    Alam Zeb

    2017-01-01

    Full Text Available Desi Ghee was thermally oxidized at 160°C for 9 h and characterized for peroxide value (PV, free fatty acid (FFA, thiobarbituric acid reactive substances (TBARS, radical scavenging activity (RSA, and fatty acid and cholesterol composition using GC-MS. Oxidized (OG and normal ghee (NG were fed to rabbits in different doses. Blood was collected for hematology and biochemical analyses after 7 and 14 days. The oxidation of desi ghee increased the PV, FFA, and TBARS values and showed a decline in the RSA values. GC-MS revealed that desi ghee was rich in saturated fatty acids (55.9 g/100 g and significant amounts of oleic acid (26.2 g/100 g. The OG significantly decreased the body weight, which was normalized by the coadministration of NG. Serum lipid profile showed a dose dependent increase in total cholesterol, triglycerides, and low density lipoproteins (LDL and decrease in RBCs count, hematocrit, glucose, and hemoglobin concentration with OG feeding. These parameters were normalized by coadministration of NG. Liver histopathology of OG fed groups showed bile duct dilation and necrotic changes, while normal architecture showed in NG groups, compared to control. These results indicate that NG has no significant effect on rabbits comparing with OG and that it was beneficial when coadministered with oxidized ghee.

  1. Preparation and properties of highly conductive palmitic acid/graphene oxide composites as thermal energy storage materials

    International Nuclear Information System (INIS)

    Mehrali, Mohammad; Latibari, Sara Tahan; Mehrali, Mehdi; Indra Mahlia, Teuku Meurah; Cornelis Metselaar, Hendrik Simon

    2013-01-01

    PA/GO (palmitic acid/graphene oxide) as PCMs (phase change materials) prepared by vacuum impregnation method, have high thermal conductivity. The GO (graphene oxide) composite was used as supporting material to improve thermal conductivity and shape stabilization of composite PCM (phase change material). SEM (Scanning electronic microscope), FT-IR (Fourier transformation infrared spectroscope) and XRD (X-ray diffractometer) were applied to determine microstructure, chemical structure and crystalloid phase of palmitic acid/GO composites, respectively. DSC (Differential scanning calorimeter) test was done to investigate thermal properties which include melting and solidifying temperatures and latent heat. FT-IR analysis represented that the composite instruction of porous palmitic acid and GO were physical. The temperatures of melting, freezing and latent heats of the composite measured through DSC analysis were 60.45, 60.05 °C, 101.23 and 101.49 kJ/kg, respectively. Thermal cycling test showed that the form-stable composite PCM has good thermal reliability and chemical stability. Thermal conductivity of the composite PCM was improved by more than three times from 0.21 to 1.02. As a result, due to their acceptable thermal properties, good thermal reliability, chemical stability and great thermal conductivities, we can consider the prepared form-stable composites as highly conductive PCMs for thermal energy storage applications. - Highlights: • Novel composite PCM with high thermal conductivity and latent heat storage. • New thermal cycling test for thermal reliability of composite PCMs. • Increasing thermal conductivity of composite PCM with graphene oxide. • Increasing thermal stability of phase change material by adding graphene oxide

  2. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors.

    Science.gov (United States)

    Çakır, M Cihan; Çalışkan, Deniz; Bütün, Bayram; Özbay, Ekmel

    2016-09-29

    Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO) heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption-dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  3. Photoelectrochemical and electrocatalytic properties of thermally oxidized copper oxide for efficient solar fuel production

    KAUST Repository

    Garcia Esparza, Angel T.

    2014-01-01

    We report the use of a facile and highly scalable synthesis process to control growth products of earth-abundant Cu-based oxides and their application in relevant photoelectrochemical and electrochemical solar fuel generation systems. Characterization of the synthesized Cu(I)/Cu(II) oxides indicates that their surface morphology and chemical composition can be simply tuned by varying two synthesis parameters (time and temperature). UV-Vis spectroscopy and impedance spectroscopy studies are performed to estimate the band structures and electronic properties of these p-type semiconductor materials. Photoelectrodes made of Cu oxides possess favorable energy band structures for production of hydrogen from water; the position of their conduction band is ≈1 V more negative than the water-reduction potential. High acceptor concentrations on the order of 1018-1019 cm-3 are obtained, producing large electric fields at the semiconductor-electrolyte interface and thereby enhancing charge separation. The highly crystalline pristine samples used as photocathodes in photoelectrochemical cells exhibit high photocurrents under AM 1.5G simulated illumination. When the samples are electrochemically reduced under galvanostatic conditions, the co-existence of the oxide with metallic Cu on the surface seems to function as an effective catalyst for the selective electrochemical reduction of CO2. © the Partner Organisations 2014.

  4. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors

    Directory of Open Access Journals (Sweden)

    M. Cihan Çakır

    2016-09-01

    Full Text Available Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption–dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  5. Heat recovery investigation from dryer–thermal oxidizer system in corn-ethanol plants

    International Nuclear Information System (INIS)

    Olszewski, Pawel

    2015-01-01

    In recent years, annual corn ethanol production in the U.S. has exceeded 13,298,000,000 gallons. However, net energy balance for this sector became a subject of controversy in many discussions. The aim of the presented research is an investigation of thermal improvement opportunities in a corn ethanol plant. For this purpose, a complex mathematical model was developed for a dryer–thermal oxidizer system. Three variants were subjected thermodynamic analyses: one state of the art system and two proposed system modifications. The properties of humid gas, a mixture of combustion products and moisture evaporated from distiller's grain, were updated based on the steam properties according to the formulation proposed by the International Association for the Properties of Water and Steam. All calculations were performed by uniquely-developed C++ code. The results indicate major potential for improvement in the following areas: (i) water recovery from humid gas; (ii) heat recovery from moisture condensation – max. 44% of total primary energy usage (TPEU); and (iii) fuel savings by reduction of humid gas flow through a thermal oxidizer – max. 1.4% of TPEU. Also the presented analysis can be a starting point for further modifications in real corn ethanol manufacturing applications, leading towards pilot system implementation. - Highlights: • Mathematical model for dryer–oxidizer system in a corn ethanol plant was proposed. • Three configurations were discussed: with intercooler, regenerator, and recuperator. • Recovery rate of water condensed at various conditions and locations was quantified. • Heat recovery possibilities at various temperatures and locations have been assessed. • Energy savings in thermal oxidizer due to preliminary condensation were calculated

  6. Potential Health Implications of the Consumption of Thermally-Oxidized Cooking Oils – a Review

    OpenAIRE

    Falade Ayodeji Osmund; Oboh Ganiyu; Okoh Anthony Ifeanyi

    2017-01-01

    Cooking oils are an integral part of a human diet as they are used in almost all types of culinary practices. They serve as sources of lipids with a significant nutritive value and health benefits which can be attributed to their fatty acid compositions and biological antioxidants. However, cooking oils are usually subjected to thermal oxidation which occurs when fresh cooking oil is heated at high temperatures during various food preparations. Repeated use of cooking oils in the commercial f...

  7. Gas sensing properties of nanocrystalline metal oxide powders produced by thermal decomposition and mechanochemical processing

    OpenAIRE

    Kersen, Ülo

    2003-01-01

    The objective of this research, was the synthesis of LaFeO3 and SnO2 fine powders for the subsequent preparation of thick film gas sensors. On producing fine metal oxide powders, often it is not possible to ensure separation of the particles during the synthesis, resulting in the formation of highly agglomerated material. In addition, there are often high synthetic costs associated with the powders obtained by these methods. Thermal decomposition and mechanochemical processing methods wer...

  8. Thermal oxidative and ozone oxidative stabilization effect of hybridized functional graphene oxide in a silica-filled solution styrene butadiene elastomer.

    Science.gov (United States)

    Su, Juqiao; Zhao, Zhongguo; Huang, Yajiang; Liao, Xia; Yang, Qi

    2016-10-26

    Hybridization of modified functional graphene oxide (fGO) in silica-filled solution styrene butadiene rubber (SSBR) endows preferable tensile and dynamic properties before and after thermal oxidative aging, and similar mechanical hysteresis performance compared with the composites without fGO. The preventing mechanism of fGO is attributed to its intrinsic peroxy radical scavenging and gas barrier abilities, which significantly reduces the peroxy radical concentration and oxygen permeability of nanocomposites and then prolongs oxidative induction time (OIT), characterized by differential scanning calorimetry (DSC). The ozone resisting effect of different loadings of fGO on nanocomposites have also been investigated by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) after ozonization under 50 ppm ozone concentration. As a result, incorporation of fGO apparently suppresses both the formation of oxygenic groups of the olefinic elastomer and crack morphology extension upon ozonization. We propose that fGO protects the SSBR elastomer from ozone attack through the conjugated delocalized π-bonds of the fGO instead of the C[double bond, length as m-dash]C bonds of the elastomer matrix being attacked, and the compared experiments, characterized by X-ray photoelectron spectroscopy (XPS), confirm that this presumption is perhaps reasonable. Moreover, more than 3 phr incorporation of fGO in nanocomposites deteriorates the chemical and mechanical properties of the elastomer during the thermal oxidation and ozonization because of the cleavage influence of oxygenic groups on peroxy radicals.

  9. Características de las bebidas con proteína de soya.

    OpenAIRE

    Vanegas Pérez, Luz Stella; Restrepo Molina, Diego Alonso; López Vargas, Jairo Humberto

    2011-01-01

    Se describe la soya desde el punto de vista bromatológico, nutricional y funcional, igualmente se desarrollan los aspectos asociados a los beneficios para la salud que han obtenido diversos autores mediante estudios clínicos, identificando los componentes responsables de esta acción. Posteriormente se desarrollan las características de funcionalidad fisicoquímica de la proteína de soya y su incidencia en los atributos sensoriales de las bebidas con soya, incluyendo las deficiencias que ésta p...

  10. Wet oxidative degradation of cellulosic wastes 5- chemical and thermal properties of the final waste forms

    International Nuclear Information System (INIS)

    Eskander, S.B.; Saleh, H.M.

    2002-01-01

    In this study, the residual solution arising from the wet oxidative degradation of solid organic cellulosic materials, as one of the component of radioactive solid wastes, using hydrogen peroxide as oxidant. Were incorporated into ordinary Portland cement matrix. Leaching as well as thermal characterizations of the final solidified waste forms were evaluated to meet the final disposal requirements. Factors, such as the amount of the residual solution incorporated, types of leachant. Release of different radionuclides and freezing-thaw treatment, that may affect the leaching characterization. Were studied systematically from the data obtained, it was found that the final solid waste from containing 35% residual solution in tap water is higher than that in ground water or sea water. Based on the data obtained from thermal analysis, it could be concluded that incorporating the residual solution form the wet oxidative degradation of cellulosic materials has no negative effect on the hydration of cement materials and consequently on the thermal stability of the final solid waste from during the disposal process

  11. The fabrication and thermal properties of bismuth-aluminum oxide nanothermometers.

    Science.gov (United States)

    Wang, Chiu-Yen; Chen, Shih-Hsun; Tsai, Ping-Hsin; Chiou, Chung-Han; Hsieh, Sheng-Jen

    2017-01-27

    Bismuth (Bi) nanowires, well controlled in length and diameter, were prepared by using an anodic aluminum oxide (AAO) template-assisted molding injection process with a high cooling rate. A high performance atomic layer deposition (ALD)-capped bismuth-aluminum oxide (Bi-Al 2 O 3 ) nanothermometer is demonstrated that was fabricated via a facile, low-cost and low-temperature method, including AAO templated-assisted molding injection and low-temperature ALD-capped processes. The thermal behaviors of Bi nanowires and Bi-Al 2 O 3 nanocables were studied by in situ heating transmission electron microscopy. Linear thermal expansion of liquid Bi within native bismuth oxide nanotubes and ALD-capped Bi-Al 2 O 3 nanocables were evaluated from 275 °C to 700 °C and 300 °C to 1000 °C, respectively. The results showed that the ALD-capped Bi-Al 2 O 3 nanocable possesses the highest working temperature, 1000 °C, and the broadest operation window, 300 °C-1000 °C, of a thermal-expanding type nanothermometer. Our innovative approach provides another way of fabricating core-shell nanocables and to further achieve sensing local temperature under an extreme high vacuum environment.

  12. Development of uranium dioxide fuel pellets with addition of beryllium oxide for increasing of thermal conductivity

    International Nuclear Information System (INIS)

    Queiroz, Carolinne Mol; Ferreira, Ricardo Alberto Neto

    2011-01-01

    The CDTN - Centro de Desenvolvimento de Tecnologia Nuclear presents a project named 'Beryllium Project' viewing to increasing the thermal conductivity of UO 2 fuel pellets, increasing the lifetime of those pellets in the reactor, generating a greater economy. This increase of conductivity is obtained by means of Be O addition to the UO 2 fuel pellets, which is very used for the production of nuclear energy. The UO 2 pellets however present a thermal conductivity relatively low, generating a high temperature gradient between the center and his side surface. The addition of beryllium oxide, with higher thermal conductivity gives pellets which will present lower temperature gradient and, consequently, more durability and better utilization of energy potential of the pellet in the reactor. (author)

  13. Effects of thermal oxidation and subsequent pickling on pitting geometry of austenitic stainless steels in chloride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Alar, Vesna; Esih, Ivan; Budic, Ivan; Brod, Slavonski [Zagreb Univ. (Croatia). Dept. of Materials

    2011-07-01

    Harmful effects of thermal oxides formed on austenitic stainless steels (SS) like AISI 304 and 316L by heating in air or other oxidizing gases on their pitting liability in chloride solutions have been studied by pursuing geometric characteristics of corrosion process (pits density, their depths, and mouth areas, ie. penetrating and superficial detrimental consequences etc.). The possibility of preventing the decay of thermally oxidized austenitic SS by chemical removal (pickling) of oxides before exposure to chloride solutions was successfully applied on simple specimens but serious difficulties arose on welded parts and on parts exposed to other temperature gradients during manufacture or in exploitation. (orig.)

  14. The effect of ethyl pyruvate on oxidative stress in intestine and bacterial translocation after thermal injury.

    Science.gov (United States)

    Karabeyoğlu, Melih; Unal, Bülent; Bozkurt, Betül; Dolapçi, Iştar; Bilgihan, Ayşe; Karabeyoğlu, Işil; Cengiz, Omer

    2008-01-01

    Thermal injury causes a breakdown in the intestinal mucosal barrier due to ischemia reperfusion injury, which can induce bacterial translocation (BT), sepsis, and multiple organ failure in burn patients. The aim of this study was to investigate the effect of ethyl pyruvate (EP) on intestinal oxidant damage and BT in burn injury. Thirty-two rats were randomly divided into four groups. The sham group was exposed to 21 degrees C water and injected intraperitoneal with saline (1 mL/100 g). The sham + EP group received EP (40 mg/kg) intraperitoneally 6 h after the sham procedure. The burn group was exposed to thermal injury and given intraperitoneal saline injection (1 mL/100 g). The burn + EP group received EP (40 mg/kg) intraperitoneally 6 h after thermal injury. Twenty-four hours later, tissue samples were obtained from mesenteric lymph nodes, spleen, and liver for microbiological analysis and ileum samples were harvested for biochemical analysis. Thermal injury caused severe BT in burn group. EP supplementation decreased BT in mesenteric lymph nodes and spleen in the burn + EP group compared with the burn group (P < 0.05). Also, burn caused BT in liver, but this finding was not statistically significant among all groups. Thermal injury caused a statistically significant increase in malondialdehyde and myeloperoxidase levels, and EP prevented this effects in the burn + EP group compared with the burn group (P < 0.05). Our data suggested that EP can inhibit the BT and myeloperoxidase and malondialdehyde production in intestine following thermal injury, suggesting anti-inflammatory and anti-oxidant properties of EP.

  15. Synthesis, characterization and thermal expansion studies on thorium-praseodymium mixed oxide solid solutions

    International Nuclear Information System (INIS)

    Panneerselvam, G.; Antony, M.P.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2010-01-01

    Full text: Thorium-praseodymium mixed oxide solid solutions containing 15, 25, 40 and 55 mole percent of praseodymia were synthesized by mixing the solutions of thorium nitrate in water and praseodymium oxide (Pr 6 O 11 ) in conc. HNO 3 . Subsequently, their hydroxides were co-precipitated by the addition of aqueous ammonia. Further the precipitate was dried at 50 deg C, calcined at 600 deg C for 4 hours and sintered at 1200 deg C for 6 h in air. X-ray diffraction measurements were performed for phase identification and lattice parameter derivation. Single-phase fluorite structure was observed for all the compositions. Bulk and theoretical densities of solid solutions were also determined by immersion and X-ray techniques. Thermal expansion coefficients and percentage linear thermal expansion of the solid solutions were determined using high temperature X-ray diffraction technique in the temperature range 300 to 1700 K for the first time. The room temperature lattice constants estimated for above compositions are 0.5578, 0.5565, 0.5545 and 0.5526 nm, respectively. The mean linear thermal expansion coefficients for the solid solutions are 15.48 x 10 -6 K -1 , 18.35 x 10 -6 K -1 , 22.65 x 10 -6 K -1 and 26.95 x 10 -6 K -1 , respectively. The percentage linear thermal expansions in this temperature range are 1.68, 1.89, 2.21 and 2.51 respectively. It is seen that the solid solutions are stable up to 1700 K. It is also seen that the effect and nature of the dopant are the important parameters influencing the thermal expansion of the ThO 2 . The lattice parameter of the solid solutions exhibited a decreasing trend with respect to praseodymia addition. The percentage linear thermal expansion of the solid solutions increases steadily with increasing temperature

  16. Thin copper oxide films prepared by ion beam sputtering with subsequent thermal oxidation: Application in chemiresistors

    Czech Academy of Sciences Publication Activity Database

    Horák, Pavel; Bejšovec, Václav; Vacík, Jiří; Lavrentiev, Vasyl; Vrňata, M.; Kormunda, M.; Daniš, S.

    2016-01-01

    Roč. 389, DEC (2016), s. 751-759 ISSN 0169-4332 R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : Copper oxide * ion beam sputtering * Van der Pauw * nuclear reaction analysis * gas sensing Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.387, year: 2016

  17. Increase of thermal conductivity of uranium dioxide nuclear fuel pellets with beryllium oxide addition

    International Nuclear Information System (INIS)

    Camarano, D.M.; Mansur, F.A.; Santos, A.M.M. dos; Ferraz, W.B.

    2016-01-01

    The UO 2 fuel is one of the most used nuclear fuel in thermal reactors and has many advantages such as high melting point, chemical compatibility with cladding, etc. However, its thermal conductivity is relatively low, which leads to a premature degradation of the fuel pellets due to a high radial temperature gradient during reactor operation. An alternative to avoid this problem is to increase the thermal conductivity of the fuel pellets, by adding beryllium oxide (BeO). Pellets of UO 2 and UO 2 -BeO were obtained from a homogenized mixture of powders of UO 2 and BeO, containing 2% and 3% by weight of BeO and sintering at 1750 °C for 3 h under H 2 atmosphere after uniaxial pressing at 400 MPa. The pellet densities were obtained by xylol penetration-immersion method and the thermal diffusivity, specific heat and thermal conductivity were determined according to ASTM E-1461 at room temperature (25 deg C) and 100 deg C. The thermal diffusivity measurements were carried out employing the laser flash method. The thermal conductivity obtained at 25 deg C showed an increase with the addition of 2% and 3% of BeO corresponding to 19% and 28%, respectively. As for the measurements carried out at 100 deg C, there was an increase in the thermal conductivity for the same BeO contents of 20% and 31%. These values as a percentage of increased conductivity were obtained in relation to the UO 2 pellets. (author)

  18. Vaporization of actinide oxides in thermal treatment processes for mixed waste

    International Nuclear Information System (INIS)

    Ebbinghaus, B.B.; Krikorian, O.H.; Adamson, M.G.

    1994-01-01

    The purpose of this study is to evaluate the volatilities of U, Pu, and Am in thermal treatment processes for mixed wastes. The thermodynamics of vaporization U and Pu oxides in the presence of oxygen and water vapor and of U oxide in the presence of oxygen and chlorine were studied. Experimental studies of U oxide volatilities by previous authors have also been reviewed. For species where data are unavailable estimation methods were used to obtain free energies of formation of the gaseous species, The data are applied to thermal treatment processes in general and then more specifically to conditions representative of the Rocky Flats Plant Fluidized Bed Unit. (RFP FBU), molten salt oxidizer, and an incinerator. U volatilities are greatest ranging from 2.67 x 10 -7 gU/h in the RFP FBU to 4. 00 gU/h for typical incinerator conditions. Pu volatilities are almost 5 orders of magnitude less than U and Am volatilities are about 3 orders of magnitude less than Pu

  19. Tetradentate Schiff base ligands and their complexes: Synthesis, structural characterization, thermal, electrochemical and alkane oxidation

    Science.gov (United States)

    Ceyhan, Gökhan; Köse, Muhammet; McKee, Vickie; Uruş, Serhan; Gölcü, Ayşegül; Tümer, Mehmet

    Three Schiff base ligands (H2L1-H2L3) with N2O2 donor sites were synthesized by condensation of 1,5-diaminonapthalene with benzaldehyde derivatives. A series of Cu(II), Co(II), Ni(II), Mn(II) and Cr(III) complexes were prepared and characterized by spectroscopic and analytical methods. Thermal, electrochemical and alkane oxidation reactions of the ligands and their metal complexes were investigated. Extensive application of 1D (1H, 13C NMR) and 2D (COSY, HETCOR, HMBC and TOSCY) NMR techniques were used to characterize the structures of the ligands and establish the 1H and 13C resonance assignments of the three ligands. Ligands H2L1 and H2L3 were obtained as single crystals from THF solution and characterized by X-ray diffraction. Both molecules are centrosymmetric and asymmetric unit contains one half of the molecule. Catalytic alkane oxidation reactions with the transition metal complexes investigated using cyclohexane and cyclooctane as substrates. The Cu(II) and Cr(III) complexes showed good catalytic activity in the oxidation of cyclohexane and cyclooctane to desired oxidized products. Electrochemical and thermal properties of the compounds were also investigated.

  20. Oxidation and crystallization behavior of calcium europium silicon nitride thin films during rapid thermal processing

    Energy Technology Data Exchange (ETDEWEB)

    Jong, M. de, E-mail: m.dejong-1@tudelft.nl [Faculty of Applied Science, Delft University of Technology, Mekelweg 15, 2629JB Delft (Netherlands); Enter, V.E. van, E-mail: vvanenter@gmail.com [Faculty of Applied Science, Delft University of Technology, Mekelweg 15, 2629JB Delft (Netherlands); Schuring, E.W., E-mail: schuring@ecn.nl [Energy Center of the Netherlands, Westerduinweg 3, 1755LE Petten (Netherlands); Kolk, E. van der, E-mail: e.vanderkolk@tudelft.nl [Faculty of Applied Science, Delft University of Technology, Mekelweg 15, 2629JB Delft (Netherlands)

    2016-03-31

    Luminescent thin films were fabricated on silicon wafers using reactive magnetron sputtering of Ca, Si and Eu in Ar/N{sub 2} atmosphere. In order to activate the luminescence, the as-deposited nitride films were heated to 1100 °C by a rapid thermal processing treatment. X-ray diffraction measurements reveal the crystal phases that form during thermal treatment. By recording scanning electron microscopy images of the surface and the cross-section of the film at different radial locations, the formation of different layers with a thickness depending on the radial position is revealed. Energy dispersive x-ray spectroscopy analysis of these cross-sections reveals the formation of an oxide top layer and a nitride bottom layer. The thickness of the top layer increases as a function of radial position on the substrate and the thickness of the bottom layer decreases accordingly. The observation of different 4f{sup 6}5d{sup 1} → 4f{sup 7} Eu{sup 2+} luminescence emission bands at different radial positions correspond to divalent Eu doped Ca{sub 3}Si{sub 2}O{sub 4}N{sub 2}, Ca{sub 2}SiO{sub 4} and CaSiO{sub 3}, which is in agreement with the phases identified by X-ray diffraction analysis. A mechanism for the observed oxidation process of the nitride films is proposed that consists of a stepwise oxidation from the as-deposited amorphous nitride state to crystalline Ca{sub 3}Si{sub 2}O{sub 4}N{sub 2}, to Ca{sub 2}SiO{sub 4} and finally CaSiO{sub 3}. The oxidation rate and final state of oxidation show a strong temperature–time dependency during anneal treatment. - Highlights: • A thin film of nitridated Ca, Si and Eu was deposited using magnetron sputtering. • Rapid thermal processing (RTP) results in Eu{sup 2+} doped Ca{sub 3}Si{sub 2}O{sub 4}N{sub 2}, Ca{sub 2}SiO{sub 4}, and CaSiO{sub 3}. • Oxidation rate differs with radial position due to a temperature gradient during RTP. • Cross-section SEM–EDX shows how the oxidation progresses in lateral direction.

  1. Evidence of nanocrystalline semiconducting graphene monoxide during thermal reduction of graphene oxide in vacuum.

    Science.gov (United States)

    Mattson, Eric C; Pu, Haihui; Cui, Shumao; Schofield, Marvin A; Rhim, Sonny; Lu, Ganhua; Nasse, Michael J; Ruoff, Rodney S; Weinert, Michael; Gajdardziska-Josifovska, Marija; Chen, Junhong; Hirschmugl, Carol J

    2011-12-27

    As silicon-based electronics are reaching the nanosize limits of the semiconductor roadmap, carbon-based nanoelectronics has become a rapidly growing field, with great interest in tuning the properties of carbon-based materials. Chemical functionalization is a proposed route, but syntheses of graphene oxide (G-O) produce disordered, nonstoichiometric materials with poor electronic properties. We report synthesis of an ordered, stoichiometric, solid-state carbon oxide that has never been observed in nature and coexists with graphene. Formation of this material, graphene monoxide (GMO), is achieved by annealing multilayered G-O. Our results indicate that the resulting thermally reduced G-O (TRG-O) consists of a two-dimensional nanocrystalline phase segregation: unoxidized graphitic regions are separated from highly oxidized regions of GMO. GMO has a quasi-hexagonal unit cell, an unusually high 1:1 O:C ratio, and a calculated direct band gap of ∼0.9 eV.

  2. Thermal performance of fresh mixed-oxide fuel in a fast flux LMR [liquid metal reactor

    International Nuclear Information System (INIS)

    Ethridge, J.L.; Baker, R.B.

    1985-01-01

    A test was designed and irradiated to provide power-to-melt (heat generation rate necessary to initiate centerline fuel melting) data for fresh mixed-oxide UO 2 -PuO 2 fuel irradiated in a fast neutron flux under prototypic liquid metal reactor (LMR) conditions. The fuel pin parameters were selected to envelope allowable fabrication ranges and address mass production of LMR fuel using sintered-to-size techniques. The test included fuel pins with variations in fabrication technique, pellet density, fuel-to-cladding gap, Pu concentration, and fuel oxygen-to-metal ratios. The resulting data base has reestablished the expected power-to-melt in mixed-oxide fuels during initial reactor startup when the fuel temperatures are expected to be the highest. Calibration of heat transfer models of fuel pin performance codes with these data are providing more accurate capability for predicting steady-state thermal behavior of current and future mixed-oxide LMR fuels

  3. Thermal analysis of thermo-gravimetric measurements of spent nuclear fuel oxidation rates

    International Nuclear Information System (INIS)

    Cramer, E.R.

    1997-01-01

    A detailed thermal analysis was completed of the sample temperatures in the Thermo-Gravimetric Analysis (TGA) system used to measure irradiated N Reactor fuel oxidation rates. Sample temperatures during the oxidation process did not show the increase which was postulated as a result of the exothermic reactions. The analysis shows the axial conduction of heat in the sample holder effectively removes the added heat and only a very small, i.e., <10 C, increase in temperature is calculated. A room temperature evaporation test with water showed the sample thermocouple sensitivity to be more than adequate to account for a temperature change of approximately 5 C. Therefore, measured temperatures in the TGA are within approximately 10 C of the actual sample temperatures and no adjustments to reported data to account for the heat input from the oxidation process are necessary

  4. Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system.

    Science.gov (United States)

    Hădărugă, Daniel I; Hădărugă, Nicoleta G; Costescu, Corina I; David, Ioan; Gruia, Alexandra T

    2014-01-01

    Ocimum basilicum L. essential oil and its β-cyclodextrin (β-CD) complex have been investigated with respect to their stability against the degradative action of air/oxygen and temperature. This supramolecular system was obtained by a crystallization method in order to achieve the equilibrium of complexed-uncomplexed volatile compounds in an ethanol/water solution at 50 °C. Both the raw essential oil and its β-CD complex have been subjected to thermal and oxidative degradation conditions in order to evaluate the protective capacity of β-CD. The relative concentration of the O. basilicum L. essential oil compounds, as determined by GC-MS, varies accordingly with their sensitivity to the thermal and/or oxidative degradation conditions imposed. Furthermore, the relative concentration of the volatile O. basilicum L. compounds found in the β-CD complex is quite different in comparison with the raw material. An increase of the relative concentration of linalool oxide from 0.3% to 1.1%, in addition to many sesquiterpene oxides, has been observed. β-CD complexation of the O. basilicum essential oil modifies the relative concentration of the encapsulated volatile compounds. Thus, linalool was better encapsulated in β-CD, while methylchavicol (estragole) was encapsulated in β-CD at a concentration close to that of the raw essential oil. Higher relative concentrations from the degradation of the oxygenated compounds such as linalool oxide and aromadendren oxide were determined in the raw O. basilicum L. essential oil in comparison with the corresponding β-CD complex. For the first time, the protective capability of natural β-CD for labile basil essential oil compounds has been demonstrated.

  5. Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

    Directory of Open Access Journals (Sweden)

    Daniel I. Hădărugă

    2014-11-01

    Full Text Available Ocimum basilicum L. essential oil and its β-cyclodextrin (β-CD complex have been investigated with respect to their stability against the degradative action of air/oxygen and temperature. This supramolecular system was obtained by a crystallization method in order to achieve the equilibrium of complexed–uncomplexed volatile compounds in an ethanol/water solution at 50 °C. Both the raw essential oil and its β-CD complex have been subjected to thermal and oxidative degradation conditions in order to evaluate the protective capacity of β-CD. The relative concentration of the O. basilicum L. essential oil compounds, as determined by GC–MS, varies accordingly with their sensitivity to the thermal and/or oxidative degradation conditions imposed. Furthermore, the relative concentration of the volatile O. basilicum L. compounds found in the β-CD complex is quite different in comparison with the raw material. An increase of the relative concentration of linalool oxide from 0.3% to 1.1%, in addition to many sesquiterpene oxides, has been observed. β-CD complexation of the O. basilicum essential oil modifies the relative concentration of the encapsulated volatile compounds. Thus, linalool was better encapsulated in β-CD, while methylchavicol (estragole was encapsulated in β-CD at a concentration close to that of the raw essential oil. Higher relative concentrations from the degradation of the oxygenated compounds such as linalool oxide and aromadendren oxide were determined in the raw O. basilicum L. essential oil in comparison with the corresponding β-CD complex. For the first time, the protective capability of natural β-CD for labile basil essential oil compounds has been demonstrated.

  6. Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

    Science.gov (United States)

    Hădărugă, Nicoleta G; Costescu, Corina I; David, Ioan; Gruia, Alexandra T

    2014-01-01

    Summary Ocimum basilicum L. essential oil and its β-cyclodextrin (β-CD) complex have been investigated with respect to their stability against the degradative action of air/oxygen and temperature. This supramolecular system was obtained by a crystallization method in order to achieve the equilibrium of complexed–uncomplexed volatile compounds in an ethanol/water solution at 50 °C. Both the raw essential oil and its β-CD complex have been subjected to thermal and oxidative degradation conditions in order to evaluate the protective capacity of β-CD. The relative concentration of the O. basilicum L. essential oil compounds, as determined by GC–MS, varies accordingly with their sensitivity to the thermal and/or oxidative degradation conditions imposed. Furthermore, the relative concentration of the volatile O. basilicum L. compounds found in the β-CD complex is quite different in comparison with the raw material. An increase of the relative concentration of linalool oxide from 0.3% to 1.1%, in addition to many sesquiterpene oxides, has been observed. β-CD complexation of the O. basilicum essential oil modifies the relative concentration of the encapsulated volatile compounds. Thus, linalool was better encapsulated in β-CD, while methylchavicol (estragole) was encapsulated in β-CD at a concentration close to that of the raw essential oil. Higher relative concentrations from the degradation of the oxygenated compounds such as linalool oxide and aromadendren oxide were determined in the raw O. basilicum L. essential oil in comparison with the corresponding β-CD complex. For the first time, the protective capability of natural β-CD for labile basil essential oil compounds has been demonstrated. PMID:25550747

  7. Soya food intake and risk of endometrial cancer among Chinese women in Shanghai: population based case-control study

    Science.gov (United States)

    Xu, Wang Hong; Zheng, Wei; Xiang, Yong Bing; Ruan, Zhi Xian; Cheng, Jia Rong; Dai, Qi; Gao, Yu Tang; Shu, Xiao Ou

    2004-01-01

    Objective To evaluate the association of intake of soya food, a rich source of phytoestrogens, with the risk of endometrial cancer. Design Population based case-control study, with detailed information on usual soya food intake over the past five years collected by face to face interview using a food frequency questionnaire. Setting Urban Shanghai, China. Participants 832 incident cases of endometrial cancer in women aged of 30 to 69 years diagnosed during 1997-2001 and identified from the Shanghai Cancer Registry; 846 control women frequency matched to cases on age and randomly selected from the Shanghai Residential Registry. Main outcome measures Odds ratios for risk of endometrial cancer in women with different intakes of soya foods. Results Regular consumption of soya foods, measured as amount of either soya protein or soya isoflavones, was inversely associated with the risk of endometrial cancer. Compared with women with the lowest quarter of intake, the adjusted odds ratio of endometrial cancer was reduced from 0.93 to 0.85 and 0.67 with increasing quarter of soya protein intake (P for trend 0.01). A similar inverse association was observed for soya isoflavones and soya fibre intake. The inverse association seemed to be more pronounced among women with high body mass index and waist:hip ratio. Conclusion Regular intake of soya foods is associated with a reduced risk of endometrial cancer. PMID:15136343

  8. Comparative evaluation of thermal oxidative decomposition for oil-plant residues via thermogravimetric analysis: Thermal conversion characteristics, kinetics, and thermodynamics.

    Science.gov (United States)

    Chen, Jianbiao; Wang, Yanhong; Lang, Xuemei; Ren, Xiu'e; Fan, Shuanshi

    2017-11-01

    Thermal oxidative decomposition characteristics, kinetics, and thermodynamics of rape straw (RS), rapeseed meal (RM), camellia seed shell (CS), and camellia seed meal (CM) were evaluated via thermogravimetric analysis (TGA). TG-DTG-DSC curves demonstrated that the combustion of oil-plant residues proceeded in three stages, including dehydration, release and combustion of organic volatiles, and chars oxidation. As revealed by combustion characteristic parameters, the ignition, burnout, and comprehensive combustion performance of residues were quite distinct from each other, and were improved by increasing heating rate. The kinetic parameters were determined by Coats-Redfern approach. The results showed that the most possible combustion mechanisms were order reaction models. The existence of kinetic compensation effect was clearly observed. The thermodynamic parameters (ΔH, ΔG, ΔS) at peak temperatures were calculated through the activated complex theory. With the combustion proceeding, the variation trends of ΔH, ΔG, and ΔS for RS (RM) similar to those for CS (CM). Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Thermal Cyclability of Reactive Air Braze Seals in Anode Supported Solid Oxide Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, John S.; Darsell, Jens T.; Coyle, Christopher A.; Birnbaum, Jerome C.; Weil, K. Scott

    2004-12-31

    The popularity of anode-supported solid oxide fuel cells (SOFC) has increased in tandem with the ability to fabricate thinner gas-tight yttrium-stabilized zirconia (YSZ) electrolyte layers, which can now be routinely produced on the order of 7 to 10 μm thick. While this has significantly improved power output and decreased the required fuel cell operating temperatures, the ability to reliably seal fuel cells remains a concern. The seals must be hermetic and be robust enough to retain their hermeticity even under the extreme operating conditions of SOFCs. Perhaps the largest contributor to stresses experienced by the seal is the fact that the SOFC is an assembly of many different materials with different thermal expansion properties. Although every effort is made to minimize thermal expansion mismatches across the seals, the stresses developed during thermal cycling still jeopardize seal integrity. Reactive air brazing (RAB), a method of joining that employs a metallic, and therefore non-brittle, seal material has been used to seal electrolyte/anode bilayers, such as those in anode-supported SOFCs, to Crofer-22 alloy. The results of rupture strength testing will be reported for as-brazed and thermally cycled samples and the effect of thermal cycling on the RAB seal microstructure will be shown

  10. Mechanical and Thermal Properties of Epoxy Composites Containing Zirconium Oxide Impregnated Halloysite Nanotubes

    Directory of Open Access Journals (Sweden)

    Moon il Kim

    2017-12-01

    Full Text Available Liquid epoxy resins have received much attention from both academia and the chemical industry as eco-friendly volatile organic compound (VOC-free alternatives for applications in coatings and adhesives, especially in those used in households. Epoxy resins show high chemical resistance and high creep resistance. However, due to their brittleness and lack of thermal stability, additional fillers are needed for improving the mechanical and thermal properties. Halloysite nanotubes (HNTs are naturally abundant, inexpensive, and eco-friendly clay minerals that are known to improve the mechanical and thermal properties of epoxy composites after suitable surface modification. Zirconium is well known for its high resistance to heat and wear. In this work, zirconium oxide-impregnated HNTs (Zr/HNTs were added to epoxy resins to obtain epoxy composites with improved mechanical and thermal properties. Zr/HNTs were characterized by field-emission transmission electron microscopy, transmission electron microscopy with energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Changes in the thermal properties of the epoxy composites were characterized by thermo mechanical analysis and differential scanning calorimetry. Furthermore, flexural properties of the composites were analyzed using a universal testing machine.

  11. Non-Parametric Kinetic (NPK Analysis of Thermal Oxidation of Carbon Aerogels

    Directory of Open Access Journals (Sweden)

    Azadeh Seifi

    2017-05-01

    Full Text Available In recent years, much attention has been paid to aerogel materials (especially carbon aerogels due to their potential uses in energy-related applications, such as thermal energy storage and thermal protection systems. These open cell carbon-based porous materials (carbon aerogels can strongly react with oxygen at relatively low temperatures (~ 400°C. Therefore, it is necessary to evaluate the thermal performance of carbon aerogels in view of their energy-related applications at high temperatures and under thermal oxidation conditions. The objective of this paper is to study theoretically and experimentally the oxidation reaction kinetics of carbon aerogel using the non-parametric kinetic (NPK as a powerful method. For this purpose, a non-isothermal thermogravimetric analysis, at three different heating rates, was performed on three samples each with its specific pore structure, density and specific surface area. The most significant feature of this method, in comparison with the model-free isoconversional methods, is its ability to separate the functionality of the reaction rate with the degree of conversion and temperature by the direct use of thermogravimetric data. Using this method, it was observed that the Nomen-Sempere model could provide the best fit to the data, while the temperature dependence of the rate constant was best explained by a Vogel-Fulcher relationship, where the reference temperature was the onset temperature of oxidation. Moreover, it was found from the results of this work that the assumption of the Arrhenius relation for the temperature dependence of the rate constant led to over-estimation of the apparent activation energy (up to 160 kJ/mol that was considerably different from the values (up to 3.5 kJ/mol predicted by the Vogel-Fulcher relationship in isoconversional methods

  12. Composition-thermal expandability relations and oxidation processes in tourmaline studied by in situ Raman spectroscopy

    Science.gov (United States)

    Watenphul, Anke; Malcherek, Thomas; Wilke, Franziska D. H.; Schlüter, Jochen; Mihailova, Boriana

    2017-11-01

    The crystal chemistry of tourmaline, XY3Z6(T6O18)(BO3)3V3W, has a strong influence on the structure and physical properties. Since tourmalines occur in a wide range of geological settings and have large temperature and pressure stability fields, the understanding of the relation between the tourmaline chemistry and thermal expansion allows for better thermodynamic modeling of geological processes. Here, we report dynamic and static thermal expansions as well as mode Grüneisen parameters studied by Raman spectroscopy and single-crystal X-ray diffraction data on several tourmaline species. In addition, oxidation processes in fluor-schorl and Fe2+-bearing elbaite were followed by Raman spectroscopy. Our results emphasize the role of Y-/Z-site occupancy disorder to reduce the local strains and demonstrate that small-size octahedrally coordinated cations perturb the topology of the SiO4 rings, which in turn seems to enhance the anisotropic thermal-expansion response. In addition, it is shown that the temperature-dependent behavior of the VOH modes primarily depends on the occupancy of the Y site, whereas that of the WOH modes depends on the occupancy of the X site. High-temperature Raman experiments in air allowed to follow the oxidation of Fe2+ to Fe3+ in fluor-schorl by analyzing both the framework and OH-stretching phonon modes. It is further demonstrated that under the same conditions, no oxidation of iron is observed for Fe2+-bearing elbaite, which implies that at high oxygen fugacity, iron is only oxidized in tourmaline species with prevalent divalent cations at the Y site.

  13. Degradation assessment of natural weathering on low density polyethylene/thermoplastic soya spent powder blends

    Science.gov (United States)

    Nuradibah, M. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

    2015-07-01

    Soya spent powder was blended with low density polyethylene (LDPE) ranging from 5-25 wt%. Glycerol was added to soya spent powder (SSP) for preparation of thermoplastic soya spent powder (TSSP). Then, the blends were exposed to natural weathering for 6 months. The susceptibility of the LDPE/soya spent powder blends based on its tensile, morphological properties and structural changes was measured every three months. The tensile strength of LDPE/TSSP blends after 6 months of weathering was the lowest compared to the other blends whereas LDPE/SSP blends after 6 months of weathering demonstrated the lowest elongation at break (Eb). Large pore can be seen on the surface of 25 wt% of LDPE/SSP blends.

  14. Soya Saponins Induce Enteritis in Atlantic Salmon (Salmo salar L.).

    Science.gov (United States)

    Krogdahl, Åshild; Gajardo, Karina; Kortner, Trond M; Penn, Michael; Gu, Min; Berge, Gerd Marit; Bakke, Anne Marie

    2015-04-22

    Soybean meal-induced enteritis (SBMIE) is a well-described condition in the distal intestine of salmonids, and saponins have been implicated as the causal agent. However, the question remains whether saponins alone cause SBMIE. Moreover, the dose-response relationship has not been described. In a 10 week feeding trial with Atlantic salmon, a highly purified (95%) soya saponin preparation was supplemented (0, 2, 4, 6, or 10 g/kg) to two basal diets, one containing fishmeal as the major protein source (FM) and the other 25% lupin meal (LP). Saponins caused dose-dependent increases in the severity of inflammation independent of the basal diet, with concomitant alterations in digestive functions and immunological marker expression. Thus, saponins induced inflammation whether the diet contained other legume components or not. However, responses were often the same or stronger in fish fed the corresponding saponin-supplemented LP diets despite lower saponin exposure, suggesting potentiation by other legume component(s).

  15. Effect of [gamma]-irradiation on soya bean proteins

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Myung-Woo; Kang, Il-Jun (Korea Atomic Energy Research Inst., Daeduk (Korea, Republic of)); Hayashi, Yukako; Matsumura, Yasuki; Mori, Tomohiko (Kyoto Univ., Uji (Japan). Research Inst. for Food Science)

    1993-09-01

    The properties of soya beans proteins following [gamma]-irradiation (5-20 kGy) were investigated in connection with protein denaturation. Irradiation doses above 10 kGy caused a decrease in 7S and 11S components and an increase in 2S and 15S components (P < 0.05). However, subunit patterns determined by electrophoresis were not changed appreciably over the entire irradiation dose range. In the differential scanning calorimetry thermogram, the denaturation temperatures of 11S and 7S components were not affected by [gamma]-irradiation, while increased irradiation dose caused a decrease in the enthalpy values of 11S and 7S components due to protein denaturation. Changes in the circular dichroism spectra and tryptophan fluorescence intensity (P < 0.05) were observed only at 20 kGy. (author).

  16. Comparison of different test methods to assess thermal stresses of metal oxide surge arresters under pollution conditions

    International Nuclear Information System (INIS)

    Bargigia, A.; de Nigris, M.; Pigini, A.; Sironi, A.

    1992-01-01

    The report deals with the research conducted by ENEL, the Italian Electricity Board, to assess the performance of zinc oxide surge arresters under pollution condition, with special reference to the consequent thermal stress on internal active parts which can affect the energy handling capabality of the arrester and may lead, in particular conditions, even to thermal runaway

  17. Effect of soya protein on blood pressure: a meta-analysis of randomised controlled trials.

    Science.gov (United States)

    Dong, Jia-Yi; Tong, Xing; Wu, Zhi-Wei; Xun, Peng-Cheng; He, Ka; Qin, Li-Qiang

    2011-08-01

    Observational studies have indicated that soya food consumption is inversely associated with blood pressure (BP). Evidence from randomised controlled trials (RCT) on the BP-lowering effects of soya protein intake is inconclusive. We aimed to evaluate the effectiveness of soya protein intake in lowering BP. The PubMed database was searched for published RCT in the English language through to April 2010, which compared a soya protein diet with a control diet. We conducted a random-effects meta-analysis to examine the effects of soya protein on BP. Subgroup and meta-regression analyses were performed to explore possible explanations for heterogeneity among trials. Meta-analyses of twenty-seven RCT showed a mean decrease of 2·21 mmHg (95 % CI - 4·10, - 0·33; P = 0·021) for systolic BP (SBP) and 1·44 mmHg (95 % CI - 2·56, - 0·31; P = 0·012) for diastolic BP (DBP), comparing the participants in the soya protein group with those in the control group. Soya protein consumption significantly reduced SBP and DBP in both hypertensive and normotensive subjects, and the reductions were markedly greater in hypertensive subjects. Significant and greater BP reductions were also observed in trials using carbohydrate, but not milk products, as the control diet. Meta-regression analyses further revealed a significantly inverse association between pre-treatment BP and the level of BP reductions. In conclusion, soya protein intake, compared with a control diet, significantly reduces both SBP and DBP, but the BP reductions are related to pre-treatment BP levels of subjects and the type of control diet used as comparison.

  18. Apparent bioavailability of isoflavones after intake of liquid and solid soya foods

    OpenAIRE

    Franke, Adrian A.; Ashburn, Leslie A.; Kakazu, Kerry; Suzuki, Shana; Wilkens, Lynne R.; Halm, Brunhild M.

    2009-01-01

    Isoflavone (IFL) intake may provide numerous health benefits, but IFL bioavailability differences among soya foods remains uncertain. Urinary IFL excretion (UIE) was shown to provide a reliable surrogate for systemic IFL exposure and therefore can be used as a measure of ‘apparent bioavailability’ (AB). We investigated the AB of IFL in fourteen healthy adults, consuming two liquid and two solid soya foods in a crossover designed study. Volunteers consumed the foods with a self-selected breakf...

  19. Apparent bioavailability of isoflavones after intake of liquid and solid soya foods.

    Science.gov (United States)

    Franke, Adrian A; Ashburn, Leslie A; Kakazu, Kerry; Suzuki, Shana; Wilkens, Lynne R; Halm, Brunhild M

    2009-10-01

    Isoflavone (IFL) intake may provide numerous health benefits, but IFL bioavailability differences among soya foods remains uncertain. Urinary IFL excretion (UIE) was shown to provide a reliable surrogate for systemic IFL exposure and therefore can be used as a measure of 'apparent bioavailability' (AB). We investigated the AB of IFL in fourteen healthy adults, consuming two liquid and two solid soya foods in a crossover designed study. Volunteers consumed the foods with a self-selected breakfast, which was kept identical for all four soya items (soya nuts, soya milk, soya protein bar and soya protein powder drink in water; average 23.7 mg IFL, 88-96 % glycosides, by HPLC analysis) and collected all urine up to 26 h. Liquid foods showed initially higher UIE values than solid foods, but this difference was considerably reduced or disappeared entirely after 24-26 h. Conclusive AB results were obtained only after 24-26 h; earlier collections were not reliable. At 26 h, adjusted UIE values for daidzein (DE) were 20 micromol in the milk and bar and 17 micromol for the nut and powder; urinary genistein excretion was the highest in the milk group (10 micromol) followed by the nut, bar (both 6 micromol) and powder groups (5 micromol); the UIE for glycitein was the highest for bars (4 micromol), followed by powder and nuts (3 micromol), and milk (2 micromol). DE makes the largest contribution to urinary total IFL. The AB of IFL was found to be variable depending on the analyte and soya food consumed.

  20. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells.

    Science.gov (United States)

    Roubos-van den Hil, P J; Nout, M J R; Beumer, R R; van der Meulen, J; Zwietering, M H

    2009-03-01

    This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and to clarify the mechanism of action. Tempe was prepared at controlled laboratory scale using Rhizopus microsporus var. microsporus as the inoculum. Extracts of raw, soaked and cooked soya beans reduced ETEC adhesion to brush border cells by 40%. Tempe extracts reduced adhesion by 80% or more. ETEC adhesion to Caco-2 cells reduced by 50% in the presence of tempe extracts. ETEC K88 bacteria were found to interact with soya bean extracts, and this may contribute to the observed decrease of ETEC adhesion to intestinal epithelial cells. Fermented soya beans (tempe) reduce the adhesion of ETEC to intestinal epithelial cells of pig and human origin. This reduced adhesion is caused by an interaction between ETEC K88 bacteria and soya bean compounds. The results strengthen previous observations on the anti-diarrhoeal effect of tempe. This effect indicates that soya-derived compounds may reduce adhesion of ETEC to intestinal cells in pigs as well as in humans and prevent against diarrhoeal diseases.

  1. Tungsten oxide thin films grown by thermal evaporation with high resistance to leaching

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Diogo S. [Universidade Federal de Pelotas (UFPel), RS (Brazil). Centro de Ciencias Quimicas, Farmaceuticas e de Alimentos; Pazinato, Julia C.O.; Freitas, Mauricio A. de; Radtke, Claudio; Garcia, Irene T.S., E-mail: irene@iq.ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Instituto de Quimica; Dorneles, Lucio S. [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Centro de Ciencias Naturais e Exatas

    2014-05-15

    Tungsten oxides show different stoichiometries, crystal lattices and morphologies. These characteristics are important mainly when they are used as photocatalysts. In this work tungsten oxide thin films were obtained by thermal evaporation on (100) silicon substrates covered with gold and heated at 350 and 600 °C, with different deposition times. The stoichiometry of the films, morphology, crystal structure and resistance to leaching were characterized through X-ray photoelectron spectroscopy, micro-Raman spectroscopy, scanning and transmission electron microscopy, X-ray diffractometry, Rutherford backscattering spectrometry and O{sup 16} (α,α')O{sup 16} resonant nuclear reaction. Films obtained at higher temperatures show well-defined spherical nanometric structure; they are composed of WO{sub 3.1} and the presence of hydrated tungsten oxide was also observed. The major crystal structure observed is the hexagonal. Thin films obtained through thermal evaporation present resistance to leaching in aqueous media and excellent performance as photocatalysts, evaluated through the degradation of the methyl orange dye. (author)

  2. Higher bioavailability of isoflavones after a single ingestion of a soya-based supplement than a soya-based food in young healthy males.

    Science.gov (United States)

    Vergne, Sébastien; Bennetau-Pelissero, Catherine; Lamothe, Valérie; Chantre, Philippe; Potier, Mylène; Asselineau, Julien; Perez, Paul; Durand, Marlène; Moore, Nicholas; Sauvant, Patrick

    2008-02-01

    Soya isoflavones, genistein and daidzein, are the focus of numerous studies investigating their potential effects on health and results remain controversial. Bioavailability is clearly a crucial factor influencing their bioefficacy and could explain these discrepancies. This study aimed at assessing: (1) the isoflavone content of sixty-nine European soya-derivative products sold on the French market; (2) the bioavailability of isoflavones comparing supplement with food. Twelve healthy volunteers were recruited in a randomized two-way crossover trial and received 35 mg isoflavones equivalent aglycone either through supplements or through cheese, both containing different patterns of isoflavone conjugates and different daidzein:genistein ratios. A specific ELISA method was used to assess the plasma and urinary concentrations of isoflavones and thus the pharmacokinetic parameters, which were then normalized to mg of each isoflavone ingested. Results showed that the normalized Cmax of daidzein (P = 0.002) and similarly the normalized AUC0 --> infinity and Cmax of genistein (P = 0.002) from soya-based capsules were higher than that from soya-based cheese. In conclusion, this work completes studies on isoflavone bioavailability and presents new data regarding isoflavone concentrations in soya-derivative products. Assuming that isoflavone conjugation patterns do not influence isoflavone bioavailability, this study shows that isoflavones contained in capsules are more bioavailable than those contained in soya-based cheese. Although the supplement is more bioavailable, the relative importance of this is difficult to interpret as there is little evidence that supplements are biologically active in human subjects to date and further studies will be necessary for this specific supplement to prove its efficacy.

  3. Characteristics of phase-change materials containing oxide nano-additives for thermal storage

    Science.gov (United States)

    2012-01-01

    In this study, the authors report the production of nanocomposite-enhanced phase-change materials (NEPCMs) using the direct-synthesis method by mixing paraffin with alumina (Al2O3), titania (TiO2), silica (SiO2), and zinc oxide (ZnO) as the experimental samples. Al2O3, TiO2, SiO2, and ZnO were dispersed into three concentrations of 1.0, 2.0, and 3.0 wt.%. Through heat conduction and differential scanning calorimeter experiments to evaluate the effects of varying concentrations of the nano-additives on the heat conduction performance and thermal storage characteristics of NEPCMs, their feasibility for use in thermal storage was determined. The experimental results demonstrate that TiO2 is more effective than the other additives in enhancing both the heat conduction and thermal storage performance of paraffin for most of the experimental parameters. Furthermore, TiO2 reduces the melting onset temperature and increases the solidification onset temperature of paraffin. This allows the phase-change heat to be applicable to a wider temperature range, and the highest decreased ratio of phase-change heat is only 0.46%, compared to that of paraffin. Therefore, this study demonstrates that TiO2, added to paraffin to form NEPCMs, has significant potential for enhancing the thermal storage characteristics of paraffin. PMID:23127224

  4. Thermal Conductivity of Epoxy Resin Reinforced with Magnesium Oxide Coated Multiwalled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Fei-Peng Du

    2013-01-01

    Full Text Available Magnesium oxide coated multiwalled carbon nanotubes (MgO@MWNT were fabricated and dispersed into epoxy matrix. The microstructures of MgO@MWNT and epoxy/MgO@MWNT nanocomposites were characterized by TEM and SEM. Electrical resistivity and thermal conductivity of epoxy nanocomposites were investigated with high resistance meter and thermal conductivity meter, respectively. MgO@MWNT has core-shell structure with MgO as shell and nanotube as core, and the thickness of MgO shell is ca. 15 nm. MgO@MWNT has been dispersed well in the epoxy matrix. MgO@MWNT loaded epoxy nanocomposites still retain electrical insulation inspite of the filler content increase. However, thermal conductivity of epoxy was increased with the MgO@MWNT content increasing. When MgO@MWNT content reached 2.0 wt.%, thermal conductivity was increased by 89% compared to neat epoxy, higher than that of unmodified MWNT nanocomposites with the same loading content.

  5. Characteristics of phase-change materials containing oxide nano-additives for thermal storage.

    Science.gov (United States)

    Teng, Tun-Ping; Yu, Chao-Chieh

    2012-11-06

    In this study, the authors report the production of nanocomposite-enhanced phase-change materials (NEPCMs) using the direct-synthesis method by mixing paraffin with alumina (Al2O3), titania (TiO2), silica (SiO2), and zinc oxide (ZnO) as the experimental samples. Al2O3, TiO2, SiO2, and ZnO were dispersed into three concentrations of 1.0, 2.0, and 3.0 wt.%. Through heat conduction and differential scanning calorimeter experiments to evaluate the effects of varying concentrations of the nano-additives on the heat conduction performance and thermal storage characteristics of NEPCMs, their feasibility for use in thermal storage was determined. The experimental results demonstrate that TiO2 is more effective than the other additives in enhancing both the heat conduction and thermal storage performance of paraffin for most of the experimental parameters. Furthermore, TiO2 reduces the melting onset temperature and increases the solidification onset temperature of paraffin. This allows the phase-change heat to be applicable to a wider temperature range, and the highest decreased ratio of phase-change heat is only 0.46%, compared to that of paraffin. Therefore, this study demonstrates that TiO2, added to paraffin to form NEPCMs, has significant potential for enhancing the thermal storage characteristics of paraffin.

  6. Preparation and Study on Nickel Oxide Reduction of Polyacrylonitrile-Based Carbon Nanofibers by Thermal Treatment.

    Science.gov (United States)

    Lee, Yeong Ju; Kim, Hyun Bin; Jeun, Joon Pyo; Lee, Dae Soo; Koo, Dong Hyun; Kang, Phil Hyun

    2015-08-01

    Carbon materials containing magnetic nanopowder have been attractive in technological applications such as electrochemical capacitors and electromagnetic wave shielding. In this study, polyacrylonitrile (PAN) fibers containing nickel nanoparticles were prepared using an electrospinning method and thermal stabilization. The reduction of nickel oxide was investigated under a nitrogen atmosphere within a temperature range of 600 to 1,000 °C. Carbon nanofibers containing nickel nanoparticles were characterized by FE-SEM, EDS, XRD, TGA, and VSM. It was found that nickel nanoparticles were formed by a NiO reduction in PAN as a function of the thermal treatment. These results led to an increase in the coercivity of nanofibers and a decrease in the remanence magnetization.

  7. Electric field assisted thermal annealing reorganization of graphene oxide/polystyrene latex films

    Directory of Open Access Journals (Sweden)

    2011-09-01

    Full Text Available Graphene/polymer films were prepared by casting water dispersion of graphene oxide (GO in the presence of polystyrene (PS latex particles. The samples were heated up to 180°C and exposed to an external electric voltage during their annealing. We observed that for the GO/PS films deposited before the electric field assisted thermal annealing the polymer latex was embedded in the graphene sheets, while the electric field assisted thermal annealing induces a phase separation with the enrichment of the PS phase above an underlying GO layer. For the films annealed under an external electric field we have also found that as the electric current passes through the GO film, GO could be recovered to reduced GO with decreased resistance.

  8. Phase formation polycrystalline vanadium oxide via thermal annealing process under controlled nitrogen pressure

    Science.gov (United States)

    Jessadaluk, S.; Khemasiri, N.; Rahong, S.; Rangkasikorn, A.; Kayunkid, N.; Wirunchit, S.; Horprathum, M.; Chananonnawathron, C.; Klamchuen, A.; Nukeaw, J.

    2017-09-01

    This article provides an approach to improve and control crystal phases of the sputtering vanadium oxide (VxOy) thin films by post-thermal annealing process. Usually, as-deposited VxOy thin films at room temperature are amorphous phase: post-thermal annealing processes (400 °C, 2 hrs) under the various nitrogen (N2) pressures are applied to improve and control the crystal phase of VxOy thin films. The crystallinity of VxOy thin films changes from amorphous to α-V2O5 phase or V9O17 polycrystalline, which depend on the pressure of N2 carrier during annealing process. Moreover, the electrical resistivity of the VxOy thin films decrease from 105 Ω cm (amorphous) to 6×10-1 Ω cm (V9O17). Base on the results, our study show a simply method to improve and control phase formation of VxOy thin films.

  9. A novel precursor in preparation and characterization of nickel oxide nanoparticles via thermal decomposition approach

    International Nuclear Information System (INIS)

    Salavati-Niasari, Masoud; Mir, Noshin; Davar, Fatemeh

    2010-01-01

    In order to raise the need of co-surfactant in the synthesis of NiO nanoparticles, [bis(2-hydroxy-1-naphthaldehydato)nickel(II)] complex was employed as a novel precursor in thermal decomposition process using oleylamine (C 18 H 37 N) as surfactant. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible (UV-Vis) spectroscopy. Also the novel precursor thermally was treated in solid state reaction in different temperature, 400, 500, and 600 o C. Synthesized nickel oxide nanoparticles have a cubic phase with average size of 15-20 nm.

  10. Optical Band Gap and Thermal Diffusivity of Polypyrrole-Nanoparticles Decorated Reduced Graphene Oxide Nanocomposite Layer

    Directory of Open Access Journals (Sweden)

    Amir Reza Sadrolhosseini

    2016-01-01

    Full Text Available A polypyrrole-nanoparticles reduced graphene oxide nanocomposite layer was prepared using electrochemical method. The prepared samples were characterized using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and UV-visible spectroscopy. The band gap of nanocomposite layers was calculated from UV-visible spectra and the thermal diffusivity of layers was measured using a photoacoustic technique. As experimental results, the optical band gap was in the range between 3.580 eV and 3.853 eV, and thermal diffusivity was increased with increasing the layer thickness from 2.873 cm2/s to 12.446 cm2/s.

  11. Thermally stimulated currents between 300 K and 800 K in beryllium oxide

    International Nuclear Information System (INIS)

    Martinelli, J.R.

    1979-01-01

    Thermally Stimulated Polarization/Depolarization Currents (ISPC/ISDC) have been measured in ceramic Beryllium Oxide in the temperature range RT-800 K. Specimens dc biased above RT show a Thermoelectret behaviour at RT. The thermal destruction of the thermoelectret state gives rise to a TSDC spectrum with at least three current maxima. Two contributions to the induced polarization are found: one volumetric uniform and another due to space charge formation. These polarizations are related to the impurity content (mainly Si and Al) as well as to the microstructure (average grain size, grain boundary distribution, pore distribution, glassy phases) of the ceramic specimens. Some mechanisms, based on Al 3+ - compensation vacancies and charge carriers transport via grain boundaries (through pore glassy phases) are proposed to explain the observed TSDC Spectra and the electrical conductivity results. (Author) [pt

  12. Changes in Acylglycerols Composition, Quality Characteristics and In vivo Effects of Dietary Pumpkin Seed Oil upon Thermal Oxidation

    Directory of Open Access Journals (Sweden)

    Alam Zeb

    2017-07-01

    Full Text Available This study was aimed to determine the acylglycerols composition, quality characteristics, and protective role of dietary pumpkin seed oil (PSO in rabbits. PSO was thermally oxidized and analyzed for quality characteristics and acylglycerols composition using reversed phase high performance liquid chromatography with diode array detection (HPLC-DAD. Oxidized and un-oxidized oil samples were fed to the rabbits in different doses for 2 weeks. The changes in the serum biochemistry, hematology, and liver histology were studied. The levels of quality parameters such peroxide value (PV, anisidine value (AV, total phenolic contents (TPC, thiobarbituric acid reactive substances (TBARS, conjugated dienes (CD and conjugated trienes (CT significantly increased with thermal treatment. HPLC analyses revealed 10 individual triacylglycerols (TAGs, total di-acylglycerols (DAGs, mono-acylglycerols (MAGs, and total oxidized TAGs. Trilinolein (LLL, 1-oleoyl-2,3-dilinolinoyl glycerol (OLL, triolein (OOO and 1,2-distearoyl-3-palmitoyl glycerol (SSP were present in higher amounts and decreased with thermal treatment. Animal's studies showed that oxidized oils decreased the whole body weight, which was ameliorated by the co-administration of un-oxidized oils. The levels of serum biochemical parameters were improved by co-administration of pumpkin seed oils. There were no significant effects of both oxidized and un-oxidized PSO on the hematological and histological parameters of rabbits. In conclusion, nutritionally important triacylglycerols were present in PSO with protective role against the toxicity of its corresponding oxidized oils.

  13. Changes in Acylglycerols composition, quality characteristics and in vivo effects of dietary pumpkin seed oil upon thermal oxidation

    Science.gov (United States)

    Zeb, Alam; Ahmad, Sultan

    2017-07-01

    This study was aimed to determine the acylglycerols composition, quality characteristics and protective role of dietary pumpkin seed oil in rabbits. Pumpkin seed oil was thermally oxidized and analyzed for quality characteristics and acylglycerols composition using reversed phase high performance liquid chromatography with diode array detection (HPLC-DAD). Oxidized and un-oxidized oil samples were fed to the rabbits in different doses for two weeks. The changes in the serum biochemistry, hematology, and liver histology were studied. The levels of quality parameters such peroxide value (PV), anisidine value (AV), total phenolic contents (TPC), thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and conjugated trienes (CT) significantly increased with thermal treatment. HPLC analyses revealed ten individual triacylglycerols (TAGs), total di-acylglycerols (DAGs), mono-acylglycerols (MAGs), and total oxidized TAGs. Trilinolein (LLL), 1-oleoyl-2,3-dilinolinoyl glycerol (OLL), triolein (OOO) and 1,2-distearoyl-3-palmitoyl glycerol (SSP) were present in higher amounts and decreased with thermal treatment. Animal's studies showed that oxidized oils decreased the whole body weight, which was ameliorated by the co-administration of un-oxidized oils. The levels of serum biochemical parameters were improved by co-administration of pumpkin seed oils. There were no significant effects of both oxidized and un-oxidized pumpkin seed oil on the hematological and histological parameters of rabbits. In conclusion, nutritionally important triacylglycerols were present in pumpkin seed oil with protective role against the toxicity of its corresponding oxidized oils.

  14. In-depth investigation of spin-on doped solar cells with thermally grown oxide passivation

    Directory of Open Access Journals (Sweden)

    Samir Mahmmod Ahmad

    Full Text Available Solar cell industrial manufacturing, based largely on proven semiconductor processing technologies supported by significant advancements in automation, has reached a plateau in terms of cost and efficiency. However, solar cell manufacturing cost (dollar/watt is still substantially higher than fossil fuels. The route to lowering cost may not lie with continuing automation and economies of scale. Alternate fabrication processes with lower cost and environmental-sustainability coupled with self-reliance, simplicity, and affordability may lead to price compatibility with carbon-based fuels. In this paper, a custom-designed formulation of phosphoric acid has been investigated, for n-type doping in p-type substrates, as a function of concentration and drive-in temperature. For post-diffusion surface passivation and anti-reflection, thermally-grown oxide films in 50–150-nm thickness were grown. These fabrication methods facilitate process simplicity, reduced costs, and environmental sustainability by elimination of poisonous chemicals and toxic gases (POCl3, SiH4, NH3. Simultaneous fire-through contact formation process based on screen-printed front surface Ag and back surface through thermally grown oxide films was optimized as a function of the peak temperature in conveyor belt furnace. Highest efficiency solar cells fabricated exhibited efficiency of ∼13%. Analysis of results based on internal quantum efficiency and minority carried measurements reveals three contributing factors: high front surface recombination, low minority carrier lifetime, and higher reflection. Solar cell simulations based on PC1D showed that, with improved passivation, lower reflection, and high lifetimes, efficiency can be enhanced to match with commercially-produced PECVD SiN-coated solar cells. Keywords: Crystalline Si solar cells, Phosphoric acid spin-on doping, Screen printing, Thermal oxide passivation

  15. THERMAL OXIDATION KINETIC OF SESAME OIL (Sesamum indicum L. BY 1H NMR

    Directory of Open Access Journals (Sweden)

    Egon Schnitzler

    2013-06-01

    Full Text Available This study aims to investigate by, 1H NMR the thermal oxidation kinetics of sesame oil (SO and commercial sesame oil (CSO obtained from roasted and unroasted seeds, respectively. The samples were heated at 180ºC by 8 hours/day for 15 days. The 1H NMR data analysis indicated that the hydrogen concentration decreases during 96 h of heating, remaining at 69.51%, 60.63% and 42.69% of allylic (E, vinylic (V and bis-allylic (G hydrogen in SO, and 49.29%, 38.51%, 18.58% in CSO, respectively. Behaving as the first order oxidation kinetics, SO average rate constant (k = mol.L-1.h-1 was: kG = 0.088 > kV = 0.0052 > kE = 0.0037 and half-life period (h, t1/2(E = 188.37 > t1/2 (V = 134.56 > t1/2 (G = 79.04. To CSO, kG = 0.0169 > kV = 0.0101 > kE = 0.0074 and t1/2(E = 94.18 > t1/2 (V = 68.49 > t1/2 (G = 41.12. These results indicated that SO is more resistant to thermal oxidation [ t1/2] than CSO [> k, < t1/2]. The study allowed to conclude that sesame oil obtained from unroasted samples has higher thermal-stability than commercial sesame oil from roasted seeds and that their cannot be used after 14.3 and 3.6 hours, respectively, for deep-frying purposes at 180ºC.

  16. Micro solid oxide fuel cell fabricated on porous stainless steel: a new strategy for enhanced thermal cycling ability

    Science.gov (United States)

    Kim, Kun Joong; Park, Byung Hyun; Kim, Sun Jae; Lee, Younki; Bae, Hongyeul; Choi, Gyeong Man

    2016-01-01

    Miniaturized solid oxide fuel cells (micro-SOFCs) are being extensively studied as a promising alternative to Li batteries for next generation portable power. A new micro-SOFC is designed and fabricated which shows enhanced thermal robustness by employing oxide-based thin-film electrode and porous stainless steel (STS) substrate. To deposit gas-tight thin-film electrolyte on STS, nano-porous composite oxide is proposed and applied as a new contact layer on STS. The micro-SOFC fabricated on composite oxide- STS dual layer substrate shows the peak power density of 560 mW cm−2 at 550 °C and maintains this power density during rapid thermal cycles. This cell may be suitable for portable electronic device that requires high power-density and fast thermal cycling. PMID:26928921

  17. Thermally induced phase transformation in multi-phase iron oxide nanoparticles on vacuum annealing

    Science.gov (United States)

    Anupama, A. V.; Keune, W.; Sahoo, B.

    2017-10-01

    The evolution of magnetic phases in multi-phase iron oxide nanoparticles, synthesized via the transferred arc plasma induced gas phase condensation method, was investigated by X-ray diffraction, vibrating sample magnetometry and 57Fe Mössbauer spectroscopy. The particles are proposed to be consisting of three different iron oxide phases: α-Fe2O3, γ-Fe2O3 and Fe3O4. These nanoparticles were exposed to high temperature (∼935 K) under vacuum (10-3 mbar He pressure), and the thermally induced phase transformations were investigated. The Rietveld refinement of the X-ray diffraction data corroborates the least-squares fitting of the transmission Mössbauer spectra in confirming the presence of Fe3O4, γ-Fe2O3 and α-Fe2O3 phases before the thermal treatment, while only Fe3O4 and α-Fe2O3 phases exist after thermal treatment. On thermal annealing in vacuum, conversion from γ-Fe2O3 to Fe3O4 and α-Fe2O3 was observed. Interestingly, we have observed a phase transformation occurring in the temperature range ∼498 K-538 K, which is strikingly lower than the phase transformation temperature of γ-Fe2O3 to α-Fe2O3 (573-623 K) in air. Combining the results of Rietveld refinement of X-ray diffraction patterns and Mössbauer spectroscopy, we have attributed this phase transformation to the phase conversion of a metastable "defected and strained" d-Fe3O4 phase, present in the as-prepared sample, to the α-Fe2O3 phase. Stabilization of the phases by controlling the phase transformations during the use of different iron-oxide nanoparticles is the key factor to select them for a particular application. Our investigation provides insight into the effect of temperature and chemical nature of the environment, which are the primary factors governing the phase stability, suitability and longevity of the iron oxide nanomaterials prepared by the gas-phase condensation method for various applications.

  18. Effect of grain alignment on interface trap density of thermally oxidized aligned-crystalline silicon films

    Science.gov (United States)

    Choi, Woong; Lee, Jung-Kun; Findikoglu, Alp T.

    2006-12-01

    The authors report studies of the effect of grain alignment on interface trap density of thermally oxidized aligned-crystalline silicon (ACSi) films by means of capacitance-voltage (C-V) measurements. C-V curves were measured on metal-oxide-semiconductor (MOS) capacitors fabricated on ⟨001⟩-oriented ACSi films on polycrystalline substrates. From high-frequency C-V curves, the authors calculated a decrease of interface trap density from 2×1012to1×1011cm-2eV-1 as the grain mosaic spread in ACSi films improved from 13.7° to 6.5°. These results demonstrate the effectiveness of grain alignment as a process technique to achieve significantly enhanced performance in small-grained (⩽1μm ) polycrystalline Si MOS-type devices.

  19. Uniform photoresponse in thermally oxidized Ni and MoS{sub 2} heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Wei [College of Science, National University of Defense Technology, Changsha (China); National Laboratory of Solid State Microstructures, School of Physics, Nanjing University (China); Peng, Gang; Wang, Fei [College of Science, National University of Defense Technology, Changsha (China); Miao, Feng [National Laboratory of Solid State Microstructures, School of Physics, Nanjing University (China); Zhang, Xue-Ao; Qin, Shiqiao [College of Science, National University of Defense Technology, Changsha (China); State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha (China)

    2017-09-15

    Non-uniform photocurrent is usually generated at the overlapped region of the heterostructures, and its potential applications may be hindered by the spatial uniformity issue of the device photoresponse. Here, nearly a uniform photoresponse at the overlapped region of the thermally oxidized Ni and molybdenum disulphide (MoS{sub 2}) heterostructures is obtained. Further characterizations reveal that several nanometers Ni is rightly under the NiO{sub x} layer formed at the surface of the film in the oxidation process. The heterostructures based on layered MoS{sub 2}/NiO{sub x}/Ni with highly conductive bottom Ni show a high uniform photoresponse with an external quantum efficiency (EQE) of 1.4% at 532 nm. Moreover, successful integration of multiple devices suggests a great priority for such a structure for highly integrated uniform photodetectors. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Uniform photoresponse in thermally oxidized Ni and MoS2 heterostructures

    International Nuclear Information System (INIS)

    Luo, Wei; Peng, Gang; Wang, Fei; Miao, Feng; Zhang, Xue-Ao; Qin, Shiqiao

    2017-01-01

    Non-uniform photocurrent is usually generated at the overlapped region of the heterostructures, and its potential applications may be hindered by the spatial uniformity issue of the device photoresponse. Here, nearly a uniform photoresponse at the overlapped region of the thermally oxidized Ni and molybdenum disulphide (MoS 2 ) heterostructures is obtained. Further characterizations reveal that several nanometers Ni is rightly under the NiO x layer formed at the surface of the film in the oxidation process. The heterostructures based on layered MoS 2 /NiO x /Ni with highly conductive bottom Ni show a high uniform photoresponse with an external quantum efficiency (EQE) of 1.4% at 532 nm. Moreover, successful integration of multiple devices suggests a great priority for such a structure for highly integrated uniform photodetectors. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Synthesis of nanocrystalline α-Fe2O3 by using thermal oxidation of Fe Films

    Science.gov (United States)

    Fortas, G.; Saidoun, I.; Abboud, H.; Gabouze, N.; Haine, N.; Manseri, A.; Zergoug, M.; Menari, H.; Sam, S.; Cheraga, H.; Bozetine, I.

    2018-03-01

    α-Fe2O3 hematite films were prepared by thermal oxidation from Fe films electroplated on silicon. Electrodeposition of Fe thin films was carried out from a sulfate bath containing an ammonium chloride complexing agent. The electrochemical study was performed by cyclic voltammetry. The SEM analysis of the films obtained at a -1.3 V constant polarization shows dendritic grains in the form of islet. The DRX spectra exhibit characteristic iron peaks according to the face centered cubic (Fcc) structure. These samples were annealed. At a temperature of 650 ° C, a single iron oxide phase was well formed, with the hematite structure. The SEM photos show a well-assembled columnar structure with formation of nanowires at the surface of the deposit. The absorbance spectra reveal an absorption features in the ultraviolet range

  2. Thermal catalytic oxidation of octachloronaphthalene over anatase TiO2 nanomaterial and its hypothesized mechanism

    Science.gov (United States)

    Su, Guijin; Li, Qianqian; Lu, Huijie; Zhang, Lixia; Huang, Linyan; Yan, Li; Zheng, Minghui

    2015-12-01

    As an environmentally-green technology, thermal catalytic oxidation of octachloronaphthalene (CN-75) over anatase TiO2 nanomaterials was investigated at 300 °C. A wide range of oxidation intermediates, which were investigated using various techniques, could be of three types: naphthalene-ring, single-benzene-ring, and completely ring-opened products. Reactive oxygen species on anatase TiO2 surface, such as O2-• and O2-, contributed to oxidative degradation. Based on these findings, a novel oxidation degradation mechanism was proposed. The reaction at (101) surface of anatase TiO2 was used as a model. The naphthalene-ring oxidative products with chloronaphthols and hydroxyl-pentachloronaphthalene-dione, could be formed via attacking the carbon of naphthalene ring at one or more positions by nucleophilic O2-. Lateral cleavage of the naphthalene ring at different C1-C10 and C4-C9, C1-C2 and C4-C9, C1-C2 or and C3-C4 bond positions by electrophilic O2-• could occur. This will lead to the formation of tetrachlorophenol, tetrachloro-benzoic acid, tetrachloro-phthalaldehyde, and tetrachloro-acrolein-benzoic acid, partially with further transformation into tetrachlorobenzene-dihydrodiol and tetrachloro-salicylic acid. Unexpectedly, the symmetric half section of CN-75 could be completely remained with generating the intricate oxidative intermediates characteristically containing tetrachlorobenzene structure. Complete cleavage of naphthalene ring could produce the ring-opened products, such as formic and acetic acids.

  3. Air, aqueous and thermal stabilities of Ce3+ ions in cerium oxide nanoparticle layers with substrates

    KAUST Repository

    Naganuma, Tamaki

    2014-01-01

    Abundant oxygen vacancies coexisting with Ce3+ ions in fluorite cerium oxide nanoparticles (CNPs) have the potential to enhance catalytic ability, but the ratio of unstable Ce3+ ions in CNPs is typically low. Our recent work, however, demonstrated that the abundant Ce3+ ions created in cerium oxide nanoparticle layers (CNPLs) by Ar ion irradiation were stable in air at room temperature. Ce valence states in CNPs correlate with the catalytic ability that involves redox reactions between Ce3+ and Ce4+ ions in given application environments (e.g. high temperature in carbon monoxide gas conversion and immersion conditions in biomedical applications). To better understand the mechanism by which Ce3+ ions achieve stability in CNPLs, we examined (i) extra-long air-stability, (ii) thermal stability up to 500 °C, and (iii) aqueous stability of Ce 3+ ions in water, buffer solution and cell culture medium. It is noteworthy that air-stability of Ce3+ ions in CNPLs persisted for more than 1 year. Thermal stability results showed that oxidation of Ce 3+ to Ce4+ occurred at 350 °C in air. Highly concentrated Ce3+ ions in ultra-thin CNPLs slowly oxidized in water within 1 day, but stability was improved in the cell culture medium. Ce 3+ stability of CNPLs immersed in the medium was associated with phosphorus adsorption on the Ce3+ sites. This study also illuminates the potential interaction mechanisms of stable Ce3+ ions in CNPLs. These findings could be utilized to understand catalytic mechanisms of CNPs with abundant oxygen vacancies in their application environments. © The Royal Society of Chemistry 2014.

  4. Rapid and tunable selective adsorption of dyes using thermally oxidized nanodiamond.

    Science.gov (United States)

    Molavi, Hossein; Shojaei, Akbar; Pourghaderi, Alireza

    2018-03-27

    In the present study, capability of nanodiamond (ND) for the adsorption of anionic (methyl orange, MO) and cationic (methylene blue, MB) dyes from aqueous solution was investigated. Employing fourier transform infrared (FTIR) spectroscopy, Boehm titration method and zeta potential, it was found that the simple thermal oxidation of ND at 425 °C, increased the content of carboxylic acid of ND and accordingly the zeta potential of ND decreased considerably. Therefore, a series of oxidized NDs (OND) at various oxidation times and as-received untreated ND (UND) was used as adsorbents of MO and MB. The adsorption experiments exhibited that UND had large adsorption capacity, very fast adsorption kinetics and excellent selectivity for MO over MB. These results suggested that the adsorption tendency of UND toward anionic MO dye followed not only by electrostatic interactions but also via the chemical interaction caused by the strong hydrogen bond between the sulfonate groups of MO and the oxygen containing groups on the surface of UND. In contrast, ONDs exhibited higher adsorption capacity for cationic MB whose tendency toward MB increased by increasing the thermal oxidation time due to the promotion of the negative charge on the surface of OND leading to the higher electrostatic attraction. The adsorption rate of MB on ONDs was also very high. Kinetics data was well fitted with the pseudo- second-order model for most of the adsorbents. The adsorption selectivity analysis revealed that ONDs displayed more adsorption capacity for MB compared with MO which was also attributed to high electrostatic interactions of cationic dye with negative charges of ONDs. Finally, the release behavior of NDs was also demonstrated after soaking in ethanol and acetone. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Synthesis of phase-pure and monodisperse iron oxide nanoparticles by thermal decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Hufschmid, Ryan D.; Arami, Hamed; Ferguson, R. Matthew; Gonzales, Marcela; Teeman, Eric M.; Brush, Lucien N.; Browning, Nigel D.; Krishnan, Kannan M.

    2015-06-03

    We present a comprehensive template for the design and synthesis of iron oxide nanoparticles with control over size, size distribution, phase, and resulting properties. Monodisperse superparamagnetic iron oxide nanoparticles were synthesized by thermal decomposition of three different iron containing precursors (iron oleate, iron pentacarbonyl, and iron oxyhydroxide) in organic solvents under a variety of synthetic conditions. We compare the suitability of these three kinetically controlled synthesis protocols, which have in common the use of iron oleate as a starting precursor or reaction intermediate, for producing nanoparticles with specific size and magnetic properties. Monodisperse particles were produced over a tunable range of sizes from approximately 2-30 nm. Reaction parameters such as precursor concentration, addition of surfactant, temperature, ramp rate, and time were adjusted to kinetically control size and size-distribution. In particular, large quantities of excess surfactant (up to 25:1 molar ratio) alter reaction kinetics and result in larger particles with uniform size; however, there is often a trade-off between large particles and a narrow size distribution. Iron oxide phase is also critical for establishing magnetic properties. As an example, we show the importance of obtaining the required iron oxide phase for application to Magnetic Particle Imaging (MPI), and describe how phase purity can be controlled.

  6. Morphology, thermal, mechanical, and barrier properties of graphene oxide/poly(lactic acid) nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Woo; Choi, Hyun Muk [Kyonggi University, Suwon (Korea, Republic of)

    2016-01-15

    To improve the physical and gas barrier properties of biodegradable poly(lactic acid) (PLA) film, two graphene nanosheets of highly functionalized graphene oxide (0.3 wt% to 0.7 wt%) and low-functionalized graphene oxide (0.5 wt%) were incorporated into PLA resin via solution blending method. Subsequently, we investigated the effects of material parameters such as loading level and degree of functionalization for the graphene nanosheets on the morphology and properties of the resultant nanocomposites. The highly functionalized graphene oxide (GO) caused more exfoliation and homogeneous dispersion in PLA matrix as well as more sustainable suspensions in THF, compared to low-functionalized graphene oxide (LFGO). When loaded with GO from 0.3 wt% to 0.7 wt%, the glass transition temperature, degree of crystallinity, tensile strength and modulus increased steadily. The GO gave rise to more pronounced effect in the thermal and mechanical reinforcement, relative to LFGO. In addition, the preparation of fairly transparent PLA-based nanocomposite film with noticeably improved barrier performance achieved only when incorporated with GO up to 0.7wt%. As a result, GO may be more compatible with hydrophilic PLA resin, compared to LFGO, resulting in more prominent enhancement of nanocomposites properties.

  7. The kinetics and properties of thermal oxidation of silicon in TCA-O/sub 2/

    International Nuclear Information System (INIS)

    Ahmed, W.; Ahmed, E.

    1993-01-01

    The oxidation of silicon using dry O/sub 2/ is now well established as a key process for the fabrication of electronic devices in the semiconductor industry. However, this process is complicated by its sensitivity to impurities which reduce device yields. HCl can be added to O/sub 2/ to remove these impurities but due to its highly corrosive nature a safer and cleaner alternative such as trichloroethane (TCA) is desirable. In this paper, the thermal oxidation of silicon using a mixture of TCA-O/sub 2/ has been investigated in a large scale industrial system. The growth kinetics and the properties of these films have been studies and compared to oxides produced from dry 2. The addition of TCA generates HCl in situ, enhances the oxidation rate by approximately 54% nd improves the electrical properties. It was found that a 1 mol.% mixture gives the optimum process. An analysis of the data suggests that a liner parabolic growth model is applicable and provides a valuable insight into the physical phenomena governing this important process. (author)

  8. Morphology, thermal, mechanical, and barrier properties of graphene oxide/poly(lactic acid) nanocomposite films

    International Nuclear Information System (INIS)

    Kim, Seong Woo; Choi, Hyun Muk

    2016-01-01

    To improve the physical and gas barrier properties of biodegradable poly(lactic acid) (PLA) film, two graphene nanosheets of highly functionalized graphene oxide (0.3 wt% to 0.7 wt%) and low-functionalized graphene oxide (0.5 wt%) were incorporated into PLA resin via solution blending method. Subsequently, we investigated the effects of material parameters such as loading level and degree of functionalization for the graphene nanosheets on the morphology and properties of the resultant nanocomposites. The highly functionalized graphene oxide (GO) caused more exfoliation and homogeneous dispersion in PLA matrix as well as more sustainable suspensions in THF, compared to low-functionalized graphene oxide (LFGO). When loaded with GO from 0.3 wt% to 0.7 wt%, the glass transition temperature, degree of crystallinity, tensile strength and modulus increased steadily. The GO gave rise to more pronounced effect in the thermal and mechanical reinforcement, relative to LFGO. In addition, the preparation of fairly transparent PLA-based nanocomposite film with noticeably improved barrier performance achieved only when incorporated with GO up to 0.7wt%. As a result, GO may be more compatible with hydrophilic PLA resin, compared to LFGO, resulting in more prominent enhancement of nanocomposites properties.

  9. Study of high temperature oxidation of duplex and functionally graded materials of thermal barrier coating (FGM TBC)

    International Nuclear Information System (INIS)

    Saeedi, B.; Sabour, A. R.; Khodami, A. M.

    2008-01-01

    Although the number and the severity of thermal barrier coatings applications on hot section components have dramatically increased in the past decade, premature spallation failure of thermal barrier coatings , due to mismatch of thermal expansion at the metal/ceramic interface of the two coating layers, during service is still an overriding concern. Therefore, functionally graded materials with a gradual compositional variation have been introduced. In this study, comparison of properties of two different types of thermal barrier coatings was made to improve the surface characteristics on high temperature components. These thermal barrier coatings consisted of a duplex thermal barrier coatings and a five layered functionally graded thermal barrier coatings . In both coatings, Yttria partially stabilized Zirconia topcoat was deposited by air plasma spraying and Ni Cr Al Y bond coat was deposited by high velocity oxy fuel spraying. In functionally graded materials coating, functionally graded layer was sprayed by air plasma process by varying the feeding ratio of YSZ/Ni Cr Al Y powders using two separate powder feeders. Then, isothermal oxidation was carried out at 950 d eg C in atmosphere to obtain the plot of mass change vs. time to study oxidation kinetic. Microstructural and compositional changes of coating, oxides formed during service were examined by optical microscope and scanning electron microscopy with EDS. functionally graded materials coating failed after 2100 h and duplex coating failed after 1700 h. Finally, it was found that functionally graded materials coating is more qualified than duplex thermal barrier coatings and stands for a longer time

  10. Low-temperature thermal reduction of graphene oxide: In situ correlative structural, thermal desorption, and electrical transport measurements

    Science.gov (United States)

    Lipatov, Alexey; Guinel, Maxime J.-F.; Muratov, Dmitry S.; Vanyushin, Vladislav O.; Wilson, Peter M.; Kolmakov, Andrei; Sinitskii, Alexander

    2018-01-01

    Elucidation of the structural transformations in graphene oxide (GO) upon reduction remains an active and important area of research. We report the results of in situ heating experiments, during which electrical, mass spectrometry, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and transmission electron microscopy (TEM) measurements were carried out correlatively. The simultaneous electrical and temperature programmed desorption measurements allowed us to correlate the onset of the increase in the electrical conductivity of GO by five orders of magnitude at about 150 °C with the maxima of the rates of desorption of H2O, CO, and CO2. Interestingly, this large conductivity change happens at an intermediate level of the reduction of GO, which likely corresponds to the point when the graphitic domains become large enough to enable percolative electronic transport. We demonstrate that the gas desorption is intimately related to (i) the changes in the chemical structure of GO detected by XPS and Raman spectroscopy and (ii) the formation of nanoscopic holes in GO sheets revealed by TEM. These in situ observations provide a better understanding of the mechanism of the GO thermal reduction.

  11. Development of soya milk extender for semen cryopreservation of Karan Fries (crossbreed cattle).

    Science.gov (United States)

    Singh, V K; Singh, A K; Kumar, R; Atreja, S K

    2013-01-01

    Egg yolk based semen extenders are used widely, with the potential risk of xenobiotic contamination. This study was designed to develop a soya milk based extender to substitute egg yolk based extender for bovine semen cryopreservation. In the first experiment soya milk was prepared from fresh soya bean (Glycine max). Concentration of soya milk in tris based extender was standardized based on quality parameters of spermatozoa during liquid preservation at 5°C up to 72 h and compared with egg yolk tris (EYT) extender. Sperm in soya milk tris (SMT) extender with 25 percent soya milk showed no significant (P > 0.05) differences in all the quality parameters like motility, viability, membrane integrity and acrosome integrity, as compared to sperm in EYT extender up to 72h in liquid dilution. In the second experiment the Karan Fries semen was cryopreserved in SMT extender with 25 percent soya milk (selected from the first experiment) using different concentration of glycerol, as cryoprotectant, ranging from 6-7 percent with a difference of 0.2 percent to standardize optimum concentration based on post thaw motility of spermatozoa. Glycerol at a final concentration of 6.4 percent was found to be the best among all. Further, semen samples were split and cryopreserved in newly developed SMT extender containing 6.4 percent glycerol and compared with conventional EYT extender for post thaw sperm quality parameters and degree of cryocapacitation. There were no significant (P > 0.05) differences between sperm in EYT extender and SMT extender for post thaw motility, viability, membrane integrity, acrosome integrity and cryocapacitation. In conclusion, the newly developed SMT extender maintained comparable semen quality as compared to EYT extender hence it can.

  12. Electrical conductivity, thermal conductivity, and rheological properties of graphene oxide-based nanofluids

    Science.gov (United States)

    Hadadian, Mahboobeh; Goharshadi, Elaheh K.; Youssefi, Abbas

    2014-12-01

    Highly stable graphene oxide (GO)-based nanofluids were simply prepared by dispersing graphite oxide with the average crystallite size of 20 nm, in polar base fluids without using any surfactant. Electrical conductivity, thermal conductivity, and rheological properties of the nanofluids were measured at different mass fractions and various temperatures. An enormous enhancement, 25,678 %, in electrical conductivity of distilled water was observed by loading 0.0006 mass fraction of GO at 25 °C. GO-ethylene glycol nanofluids exhibited a non-Newtonian shear-thinning behavior followed by a shear-independent region. This shear-thinning behavior became more pronounced at higher GO concentrations. The maximum ratio of the viscosity of nanofluid to that of the ethylene glycol as a base fluid was 3.4 for the mass fraction of 0.005 of GO at 20 °C under shear rate of 27.5 s-1. Thermal conductivity enhancement of 30 % was obtained for GO-ethylene glycol nanofluid for mass fraction of 0.07. The measurement of the transport properties of this new kind of nanofluid showed that it could provide an ideal fluid for heat transfer and electronic applications.

  13. Thermally Stable Solution Processed Vanadium Oxide as a Hole Extraction Layer in Organic Solar Cells.

    Science.gov (United States)

    Alsulami, Abdullah; Griffin, Jonathan; Alqurashi, Rania; Yi, Hunan; Iraqi, Ahmed; Lidzey, David; Buckley, Alastair

    2016-03-25

    Low-temperature solution-processable vanadium oxide (V₂O x ) thin films have been employed as hole extraction layers (HELs) in polymer bulk heterojunction solar cells. V₂O x films were fabricated in air by spin-coating vanadium(V) oxytriisopropoxide (s-V₂O x ) at room temperature without the need for further thermal annealing. The deposited vanadium(V) oxytriisopropoxide film undergoes hydrolysis in air, converting to V₂O x with optical and electronic properties comparable to vacuum-deposited V₂O₅. When s-V₂O x thin films were annealed in air at temperatures of 100 °C and 200 °C, OPV devices showed similar results with good thermal stability and better light transparency. Annealing at 300 °C and 400 °C resulted in a power conversion efficiency (PCE) of 5% with a decrement approximately 15% lower than that of unannealed films; this is due to the relative decrease in the shunt resistance (R sh ) and an increase in the series resistance (R s ) related to changes in the oxidation state of vanadium.

  14. The use of thermal wet oxidation for enhanced biogas recovery from raw and digested biowaste

    Energy Technology Data Exchange (ETDEWEB)

    Lissens, G.; Verstraete, W. [Gent Univ. (Belgium). LabMET; Thomsen, A.B. [Rise National Lab (Denmark). Dept. of Plant Research; Ahring, B.K. [Technical Univ., of Denmark (Denmark). Environmental Microbiology and Biotechnology

    2004-07-01

    The energy content of biodegradable organic waste and sewage sludge generated in the European Union represents 8 per cent of the European petroleum consumption, or on a per capita basis about 180 litres per year. Most of this material is still incinerated or disposed of in landfills despite the potential for anaerobic digestion to make this energy available. Current biodegradation plants only convert the easily digested portion of the waste, converting this to methane, leaving the rest to be stabilized by, for instance, composting. However, increased environmental consciousness is causing researchers to look at ways of increasing the methane yield. In this study, the anaerobic biodegradability of three waste sources was investigated: source-separated food waste, woody yard waste, and mixed biowaste from yard and kitchen waste after digestion in a full-scale digester. Thermal alkaline wet oxidation was applied to establish its effect on methane production and the digestion kinetics of raw and digested biowaste in batch and continuous tests. Results show that thermal alkaline wet oxidation can significantly increase methane production. 1 fig.

  15. Comparison of human IgE-binding soya bean allergenic protein Gly m I with the antigenicity profiles of calf anti-soya protein sera

    NARCIS (Netherlands)

    Hessing, M.; Bleeker, H.; Tsuji, H.; Ogawa, T.; Vlooswijk, R.A.A.

    1996-01-01

    In the food, particularly the feed, industry, large quantities of soya bean protein products are used for the formulation of end-products destined for human or animal consumption. These basic ingredients and the final end products often have to fulfill specific requirements regarding the presence of

  16. Soya bean expansion in Mozambique : Exploring the inclusiveness and viability of soya business models as an alternative to the land grab

    NARCIS (Netherlands)

    di Matteo, F.; Otsuki, K.; Schoneveld, G.

    2016-01-01

    Throughout the world, soya beans and seeds are typically cultivated in large plantations. The way plantations have been established are often discussed as what represent the ‘global land grab’. Little has been discussed, however, about how large plantations evolve as they interact with various

  17. Effect of Layer-Graded Bond Coats on Edge Stress Concentration and Oxidation Behavior of Thermal Barrier Coatings

    Science.gov (United States)

    Zhu, Dongming; Ghosn, Louis J.; Miller, Robert A.

    1998-01-01

    Thermal barrier coating (TBC) durability is closely related to design, processing and microstructure of the coating Z, tn systems. Two important issues that must be considered during the design of a thermal barrier coating are thermal expansion and modulus mismatch between the substrate and the ceramic layer, and substrate oxidation. In many cases, both of these issues may be best addressed through the selection of an appropriate bond coat system. In this study, a low thermal expansion and layer-graded bond coat system, that consists of plasma-sprayed FeCoNiCrAl and FeCrAlY coatings, and a high velocity oxyfuel (HVOF) sprayed FeCrAlY coating, is developed to minimize the thermal stresses and provide oxidation resistance. The thermal expansion and oxidation behavior of the coating system are also characterized, and the strain isolation effect of the bond coat system is analyzed using the finite element method (FEM). Experiments and finite element results show that the layer-graded bond coat system possesses lower interfacial stresses. better strain isolation and excellent oxidation resistance. thus significantly improving the coating performance and durability.

  18. Thermally evaporated mechanically hard tin oxide thin films for opto-electronic apllications

    Energy Technology Data Exchange (ETDEWEB)

    Tripathy, Sumanta K.; Rajeswari, V. P. [Centre for Nano Science and Technology, GVP College of Engineering (Autonomous), Visakhapatnam- 530048 (India)

    2014-01-28

    Tungsten doped tin oxide (WTO) and Molybdenum doped tin oxide (MoTO) thin film were deposited on corn glass by thermal evaporation method. The films were annealed at 350°C for one hour. Structural analysis using Xray diffraction data shows both the films are polycrystalline in nature with monoclinic structure of tin oxide, Sn{sub 3}O{sub 4}, corresponding to JCPDS card number 01-078-6064. SEM photograph showed that both the films have spherical grains with size in the range of 20–30 nm. Compositional analysis was carried out using EDS which reveals the presence of Sn, O and the dopant Mo/W only thereby indicating the absence of any secondary phase in the films. The films are found to contain nearly 6 wt% of Mo, 8 wt% of W as dopants respectively. The transmission pattern for both the films in the spectral range 200 – 2000 nm shows that W doping gives a transparency of nearly 80% from 380 nm onwards while Mo doping has less transparency of 39% at 380nm. Film hardness measurement using Triboscope shows a film hardness of about 9–10 GPa for both the films. It indicates that W or M doping in tin oxide provides the films the added advantage of withstanding the mechanical wear and tear due to environmental fluctuations By optimizing the optical and electrical properties, W/Mo doped tin oxide films may be explored as window layers in opto-electronic applications such as solar cells.

  19. Enhancing mechanical and thermal properties of styrene-butadiene rubber/carboxylated acrylonitrile butadiene rubber blend by the usage of graphene oxide with diverse oxidation degrees

    Science.gov (United States)

    Xue, Xiaodong; Yin, Qing; Jia, Hongbing; Zhang, Xuming; Wen, Yanwei; Ji, Qingmin; Xu, Zhaodong

    2017-11-01

    Graphene oxide (GO) with various oxidation degrees were prepared through a modified Hummer's method by varying the dosage of oxidizing agent. Styrene-butadiene rubber (SBR)/carboxylated acrylonitrile butadiene rubber (XNBR)/GO nanocomposites were fabricated by aqueous-phase mixing of GO colloidal dispersion with SBR latex and a small loading of XNBR latex, followed by co-coagulation. Effects of GO oxidation degree on the morphology, structure, mechanical and thermal properties of nanocomposites were thoroughly investigated. The results showed that the mechanical strength of nanocomposites were enhanced with the increase of oxidation degree of GO. Especially, when the weight ratio of KMnO4 to graphite was 15/5, the tensile strength, tear strength and thermal conductivity of SBR/XNBR/GO filled with 3 phr (parts per hundred rubber) GO increased by 255.3%, 141.5% and 22.8%, respectively, compared to those of neat SBR/XNBR blend. In addition, the thermal stability and the solvent resistance of the nanocomposites were also improved significantly. This work suggested that GO with higher oxidation degree could effectively improve the properties of SBR/XNBR blend.

  20. Magnetic properties of thermally reduced graphene oxide decorated with PtNi nanoparticles

    International Nuclear Information System (INIS)

    Huízar-Félix, A.M.; Cruz-Silva, R.; Barandiarán, J.M.; García-Gutiérrez, D.I.; Orue, I.

    2016-01-01

    Nanocomposites of reduced graphene oxide (RGO) with PtNi nanoparticles were obtained by in situ thermal reduction of a physical mixture of GO and metallic precursors. RGO and PtNiRGO nanocomposites were studied by differential thermal analysis and thermogravimetry, Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), as well as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The method presented here is a one-step thermal reduction procedure that allows the deposition of bimetallic PtNi nanoparticles with tetragonal crystalline structure and particle size ranging from 3 nm to 30 nm on RGO. The magnetic properties of the RGO and PtNiRGO nanocomposites were measured by vibrating sample magnetometry, which revealed that the RGO exhibited diamagnetism at room temperature and paramagnetism at temperatures below 10 K. PtNiRGO nanocomposites show hysteresis and ferromagnetic ordering at room temperature with a Curie temperature of 658 K. In addition, its magnetic properties at low temperature were strongly influenced by the paramagnetic contribution of RGO and the morphology of the bimetallic nanoparticles. - Highlights: • Simultaneous synthesis method for growth of PtNi nanoparticles on RGO. • Microstructural features of PtNiRGO nanocomposite were studied with extensive characterization. • Diamagnetic behavior of RGO and ferromagnetic ordering for PtNiRGO nanocomposite.

  1. Enhanced thermal properties with graphene oxide in the urea-formaldehyde microcapsules containing paraffin PCMs.

    Science.gov (United States)

    Qiao, Zhen; Mao, Jian

    2017-02-01

    In this study, compact urea-formaldehyde microcapsules containing paraffin (UFP) phase change materials (PCMs) were prepared via in situ polymerisation. The thermal conductivity of the PCMs was enhanced without influencing their enthalpy by adding graphene oxide (GO). Two modification methods were investigated: One in which GO is added to the inside of microcapsules, defined as "paraffin/GO@UF composite"; and another in which GO is coated onto the surface of shell, defined as "paraffin@UF/GO composite". The GO sheets were visible in scanning electron microscope (SEM) images of paraffin@UF/GO composite. The thermal conductivity was 0.2236 ± 0.0003 W/(m·K) for UFP particles, was 0.2517 ± 0.0003 W/(m·K) for the paraffin/GO@UF composite (10 wt%), and was 1.0670 ± 0.0020 W/(m·K) for paraffin@UF/GO composite (10 wt%), respectively. The encapsulation efficiency of all samples exceeded 80% (w/w) and all samples exhibited favourable thermal stability and reliability. The IR emissivity of paraffin@UF/GO was lower than that of paraffin/GO@UF when the same GO amount was added to the composite.

  2. Thermal stability of pulsed laser deposited iridium oxide thin films at low oxygen atmosphere

    Science.gov (United States)

    Gong, Yansheng; Wang, Chuanbin; Shen, Qiang; Zhang, Lianmeng

    2013-11-01

    Iridium oxide (IrO2) thin films have been regarded as a leading candidate for bottom electrode and diffusion barrier of ferroelectric capacitors, some process related issues need to be considered before integrating ferroelectric capacitors into memory cells. This paper presents the thermal stability of pulsed laser deposited IrO2 thin films at low oxygen atmosphere. Emphasis was given on the effect of post-deposition annealing temperature at different oxygen pressure (PO2) on the crystal structure, surface morphology, electrical resistivity, carrier concentration and mobility of IrO2 thin films. The results showed that the thermal stability of IrO2 thin films was strongly dependent on the oxygen pressure and annealing temperature. IrO2 thin films can stably exist below 923 K at PO2 = 1 Pa, which had a higher stability than the previous reported results. The surface morphology of IrO2 thin films depended on PO2 and annealing temperature, showing a flat and uniform surface for the annealed films. Electrical properties were found to be sensitive to both the annealing temperature and oxygen pressure. The room-temperature resistivity of IrO2 thin films with a value of 49-58 μΩ cm increased with annealing temperature at PO2 = 1 Pa. The thermal stability of IrO2 thin films as a function of oxygen pressure and annealing temperature was almost consistent with thermodynamic calculation.

  3. Thermally insulating and fire-retardant lightweight anisotropic foams based on nanocellulose and graphene oxide

    Science.gov (United States)

    Wicklein, Bernd; Kocjan, Andraž; Salazar-Alvarez, German; Carosio, Federico; Camino, Giovanni; Antonietti, Markus; Bergström, Lennart

    2015-03-01

    High-performance thermally insulating materials from renewable resources are needed to improve the energy efficiency of buildings. Traditional fossil-fuel-derived insulation materials such as expanded polystyrene and polyurethane have thermal conductivities that are too high for retrofitting or for building new, surface-efficient passive houses. Tailored materials such as aerogels and vacuum insulating panels are fragile and susceptible to perforation. Here, we show that freeze-casting suspensions of cellulose nanofibres, graphene oxide and sepiolite nanorods produces super-insulating, fire-retardant and strong anisotropic foams that perform better than traditional polymer-based insulating materials. The foams are ultralight, show excellent combustion resistance and exhibit a thermal conductivity of 15 mW m-1 K-1, which is about half that of expanded polystyrene. At 30 °C and 85% relative humidity, the foams retained more than half of their initial strength. Our results show that nanoscale engineering is a promising strategy for producing foams with excellent properties using cellulose and other renewable nanosized fibrous materials.

  4. Magnetic properties of thermally reduced graphene oxide decorated with PtNi nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Huízar-Félix, A.M. [Universidad Autónoma de Nuevo León, UANL, Facultad de Ingeniería Mecánica y Eléctrica, FIME, Ave. Pedro de Alba s/n, Ciudad Universitaria, C.P.66455 San Nicolás de los Garza, N.L. (Mexico); Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), 48940 Leioa (Spain); BC Materials, Basque Centre for Materials, Applications and Nanostructures, 48160 Derio (Spain); Cruz-Silva, R. [Research Center for Exotic NanoCarbon, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 (Japan); Barandiarán, J.M. [Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), 48940 Leioa (Spain); BC Materials, Basque Centre for Materials, Applications and Nanostructures, 48160 Derio (Spain); García-Gutiérrez, D.I. [Universidad Autónoma de Nuevo León, UANL, Facultad de Ingeniería Mecánica y Eléctrica, FIME, Ave. Pedro de Alba s/n, Ciudad Universitaria, C.P.66455 San Nicolás de los Garza, N.L. (Mexico); Orue, I. [SGIKER Medidas Magnéticas, Facultad de Ciencia y Tecnología, Universidad del País Vasco (UPV/EHU), 48940 Leioa (Spain); and others

    2016-09-05

    Nanocomposites of reduced graphene oxide (RGO) with PtNi nanoparticles were obtained by in situ thermal reduction of a physical mixture of GO and metallic precursors. RGO and PtNiRGO nanocomposites were studied by differential thermal analysis and thermogravimetry, Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), as well as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The method presented here is a one-step thermal reduction procedure that allows the deposition of bimetallic PtNi nanoparticles with tetragonal crystalline structure and particle size ranging from 3 nm to 30 nm on RGO. The magnetic properties of the RGO and PtNiRGO nanocomposites were measured by vibrating sample magnetometry, which revealed that the RGO exhibited diamagnetism at room temperature and paramagnetism at temperatures below 10 K. PtNiRGO nanocomposites show hysteresis and ferromagnetic ordering at room temperature with a Curie temperature of 658 K. In addition, its magnetic properties at low temperature were strongly influenced by the paramagnetic contribution of RGO and the morphology of the bimetallic nanoparticles. - Highlights: • Simultaneous synthesis method for growth of PtNi nanoparticles on RGO. • Microstructural features of PtNiRGO nanocomposite were studied with extensive characterization. • Diamagnetic behavior of RGO and ferromagnetic ordering for PtNiRGO nanocomposite.

  5. A facile strategy for the reduction of graphene oxide and its effect on thermal conductivity of epoxy based composites

    Directory of Open Access Journals (Sweden)

    F. Xie

    2016-06-01

    Full Text Available A facile and efficient approach to reduce graphene oxide with Al particles and potassium hydroxide was developed at moderate temperature and the graphene/epoxy composite was prepared by mould casting method. The as-prepared graphene has been confirmed by Transmission electron microscopy, Fourier transform infrared spectrometer, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Thermal gravimetric analysis. This provides a new green way to synthesize graphene with high surface area and opens another opportunity for the production of graphene. Effects of graphene on thermal conductivity, thermal stability and microstructures of the epoxy-based composite were also investigated. The results showed that thermal conductivity of the composite exhibited a remarkable improvement with increasing content of graphene and thermal conductivity could reach 1.192 W/(m*K when filled with 3 wt% graphene. Moreover, graphene/epoxy composite exhibits good thermal stability with 3 wt% graphene.

  6. Sticking power from soya beans : higher fossil fuel prices and concerns over formaldehyde in existing glue formulations have led to a resurgence in interest in soya-based adhesives, report

    Science.gov (United States)

    James Wescott; Charles Frihart

    2011-01-01

    Soya beans have long been considered a miracle crop for their ease of growing; high concentration of vegetable oil and high protein content; and their ability to reintroduce nitrogen back into the soil. The origin of soya beans dates back to the early 11th century from the eastern half of China. They were introduced to Europe in 1712 and first...

  7. Improved oxidation of air pollutants in a non-thermal plasma

    International Nuclear Information System (INIS)

    Roland, U.; Holzer, F.; Kopinke, F.-D.

    2002-01-01

    The performance of non-thermal plasma (NTP) for the removal of organic air pollutants (especially in low concentrations) is improved by the introduction of ferroelectric and catalytically active materials into the discharge zone of an NTP reactor. Experiments with model systems (various contaminants and packed-bed materials) have shown that such a modification of a homogeneous gas-phase plasma can overcome the most serious restrictions of the NTP technique at its present state of the art: the incomplete total oxidation (i.e. the low selectivity to CO 2 ) and the energetic inefficiency. Placing a ferroelectric packed-bed material in the discharge zone was shown to result in a lowering of the energy input required. The main effects of plasma catalysis enabled by the introduction of a catalytically active material were an enhanced conversion of pollutants and a higher CO 2 selectivity. These improvements are based on the presence of short-lived oxidising species in the inner volume of porous catalysts. Additionally, the formation of a reservoir of adsorbed oxidants in the NTP zone could be shown. The combination of both modifications (ferroelectric packed-bed materials and plasma catalysis) is a promising method to support the NTP-initiated oxidation of air pollutants

  8. Enhanced mechanical properties of chitosan/nanodiamond composites by improving interphase using thermal oxidation of nanodiamond.

    Science.gov (United States)

    Delavar, Zahra; Shojaei, Akbar

    2017-07-01

    Polymer composite films based on chitosan (CS) and nanodimaond (ND) were prepared using solution casting method. ND with variable contents of carboxylic functional group was prepared using thermal oxidation at temperature of 420°C under air atmosphere at various durations of 1.5 and 4.5h. The interfacial interaction between NDs and CS and morphological evolution of CS in presence of NDs were investigated by Fourier transform infrared (FTIR), differential scanning calorimeter (DSC) and X-ray diffraction (XRD) analyses. A significant improvement in tensile strength (∼85%) and tensile modulus (∼125%) of CS was achieved by oxidized ND (OND) obtained at higher oxidation time of 4.5 at low concentrations (below 1.5wt%). Theoretical analyses based on micromechanical models showed that the ND with higher degree of carboxylic functionality provided thicker and stronger interphase region which was reflected in higher mechanical properties. The equilibrium water uptake of CS decreased by incorporating ND and increasing its degree of carboxyl functionality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Kinetics of irreversible thermal decomposition of dissociating nitrogen dioxide with nitrogen oxide or oxygen additions

    International Nuclear Information System (INIS)

    Gvozdev, A.A.

    1987-01-01

    The effect of NO or O 2 admixtures on kinetics of the irreversible thermal decomposition of nitrogen dioxide at temperatures 460-520 deg C and pressures 4-7 MPa has been studied. It follows from experimental data that the rate of N 2 O 4 formation reduces with the increase of partial pressure of oxygen or decrease of partial pressure of nitrogen oxide. The same regularity is seen for the rate of nitrogen formation. The rate constants of N 2 O formation in dissociating nitrogen tetroxide with oxygen or nitrogen oxide additions agree satisfactorily with previously published results, obtained in stoichiometric mixtures. The appreciable discrepancy at 520 deg C is bind with considerable degree of nitrogen oxide transformation which constitutes approximately 14%. It is determined that the kinetics of formation of the products of irreversible N 2 O and N 2 decomposition in stoichiometric and non-stoichiometric 2NO 2 ↔ 2NO+O 2 mixtures is described by identical 3NO → N 2 O+NO 2 and N 2 O+NO → N 2 +NO 2 reactions

  10. Identity recognition in response to different levels of genetic relatedness in commercial soya bean

    Science.gov (United States)

    Van Acker, Rene; Rajcan, Istvan; Swanton, Clarence J.

    2017-01-01

    Identity recognition systems allow plants to tailor competitive phenotypes in response to the genetic relatedness of neighbours. There is limited evidence for the existence of recognition systems in crop species and whether they operate at a level that would allow for identification of different degrees of relatedness. Here, we test the responses of commercial soya bean cultivars to neighbours of varying genetic relatedness consisting of other commercial cultivars (intraspecific), its wild progenitor Glycine soja, and another leguminous species Phaseolus vulgaris (interspecific). We found, for the first time to our knowledge, that a commercial soya bean cultivar, OAC Wallace, showed identity recognition responses to neighbours at different levels of genetic relatedness. OAC Wallace showed no response when grown with other commercial soya bean cultivars (intra-specific neighbours), showed increased allocation to leaves compared with stems with wild soya beans (highly related wild progenitor species), and increased allocation to leaves compared with stems and roots with white beans (interspecific neighbours). Wild soya bean also responded to identity recognition but these responses involved changes in biomass allocation towards stems instead of leaves suggesting that identity recognition responses are species-specific and consistent with the ecology of the species. In conclusion, elucidating identity recognition in crops may provide further knowledge into mechanisms of crop competition and the relationship between crop density and yield. PMID:28280587

  11. Granulomatous enteritis in rainbow trout (Oncorhynchus mykiss) associated with soya bean meal regardless of water dissolved oxygen level

    NARCIS (Netherlands)

    Mosberian-Tanha, P.; Landsverk, T.; Press, C.M.; Mydland, L.T.; Schrama, J.W.; Øverland, M.

    2018-01-01

    This study investigated morphological changes associated with soya bean meal-induced enteritis (SBMIE) in distal intestine (DI) of rainbow trout (Oncorhynchus mykiss) fed a soya bean meal (SBM)-based diet and exposed to normoxia or hypoxia created by optimal and low water flow rates, respectively. A

  12. Analysis of thermal treatment effects upon optico-luminescent and scintillation characteristics of oxide and chalcogenide crystals

    International Nuclear Information System (INIS)

    Ryzhikov, Vladimir D.; Grinyov, Boris V.; Pirogov, Evgeniy N.; Galkin, Sergey N.; Nagornaya, Lyudmila L.; Bondar, Vladimir G.; Babiychuk, Inna P.; Krivoshein, Vadim I.; Silin, Vitaliy I.; Lalayants, Alexandr I.; Voronkin, Evgeniy F.; Katrunov, Konstantin A.; Onishchenko, Gennadiy M.; Vostretsov, Yuriy Ya.; Malyi, Pavel Yu.; Lisetskaya, Elena K.; Lisetskii, Longin N.

    2005-01-01

    This work has been aimed at analyzing the effects of various thermal treatment factors upon optical-luminescent, scintillation and other functional characteristics of complex oxide and chalcogenide crystals. The crystals considered in this work are scintillators with intrinsic (PWO, CWO, BGO), activator (GSO:Ce) or complex-defect ZnSe(Te) type of luminescence. Important factors of thermal treatment are not only the temperature and its variation with time, but also the chemical composition of the annealing medium, its oxidation-reduction properties

  13. Thermal oxidation of cesium loaded Prussian blue as a precaution for exothermic phase change in extreme conditions

    International Nuclear Information System (INIS)

    Parajuli, Durga; Tanaka, Hisashi; Takahashi, Akira; Kawamoto, Tohru

    2013-01-01

    Cesium adsorbed Prussian blue is studied for the thermal oxidation. The TG-DTA shows exothermic phase change of micro aggregates of nano-PB at above 270°C. For this reason, Cs loaded PB was heated between 180 to 260°C. Heating at 180 removed only the water. Neither the oxidation of Iron nor the removal of cyanide is observed at this temperature. Oxidation of cyanide is observed upon heating above 200°C while loaded Cs is released after heating at >250°C followed by washing with water. Thermal oxidation between 200 to 220°C for more than 2 h showed control on exothermic phase change and loaded Cs is also not solubilized. (author)

  14. Synthesis of Mesoporous Metal Oxides by Structure Replication: Thermal Analysis of Metal Nitrates in Porous Carbon Matrices

    Directory of Open Access Journals (Sweden)

    Christian Weinberger

    2015-08-01

    Full Text Available A variety of metal nitrates were filled into the pores of an ordered mesoporous CMK-3 carbon matrix by solution-based impregnation. Thermal conversion of the metal nitrates into the respective metal oxides, and subsequent removal of the carbon matrix by thermal combustion, provides a versatile means to prepare mesoporous metal oxides (so-called nanocasting. This study aims to monitor the thermally induced processes by thermogravimetric analysis (TGA, coupled with mass ion detection (MS. The highly dispersed metal nitrates in the pores of the carbon matrix tend to react to the respective metal oxides at lower temperature than reported in the literature for pure, i.e., carbon-free, metal nitrates. The subsequent thermal combustion of the CMK-3 carbon matrix also occurs at lower temperature, which is explained by a catalytic effect of the metal oxides present in the pores. This catalytic effect is particularly strong for oxides of redox active metals, such as transition group VII and VIII metals (Mn, Fe, Co, Ni, Cu, and Ce.

  15. Effect of block composition on thermal properties and melt viscosity of poly[2-(dimethylaminoethyl methacrylate], poly(ethylene oxide and poly(propylene oxide block co-polymers

    Directory of Open Access Journals (Sweden)

    2011-09-01

    Full Text Available To modify the rheological properties of certain commercial polymers, a set of block copolymers were synthesized through oxyanionic polymerization of 2-(dimethylaminoethyl methacrylate to the chain ends of commercial prepolymers, namely poly(ethylene oxide (PEO, poly(ethylene oxide-block-poly(propylene oxide-block-poly(ethylene oxide (PEO-PPO-PEO, and poly(propylene oxide (PPO. The formed block copolymers were analysed with size exclusion chromatography and nuclear magnetic resonance spectroscopy in order to confirm block formation. Thermal characterization of the resulting polymers was done with differential scanning calorimetry. Thermal transition points were also confirmed with rotational rheometry, which was primarily used to measure melt strength properties of the resulting block co-polymers. It was observed that the synthesised poly[2-(dimethylaminoethyl methacrylate]-block (PDM affected slightly the thermal transition points of crystalline PEO-block but the influence was stronger on amorphous PPO-blocks. Frequency sweeps measured above the melting temperatures for the materials confirmed that the pre-polymers (PEO and PEO-PPO-PEO behave as Newtonian fluids whereas polymers with a PDM block structure exhibit clear shear thinning behaviour. In addition, the PDM block increased the melt viscosity when compared with that one of the pre-polymer. As a final result, it became obvious that pre-polymers modified with PDM were in entangled form, in the melted state as well in the solidified form.

  16. Grain product of 34 soya mutant lines;Rendimiento de grano de 34 lineas mutantes de soya

    Energy Technology Data Exchange (ETDEWEB)

    Salmeron E, J.; Mastache L, A. A.; Valencia E, F.; Diaz V, G. E. [Colegio Superior Agropecuario del Estado de Guerrero, Vicente Guerrero No. 81, Col. Centro, 40000 Iguala, Guerrero (Mexico); Cervantes S, T. [Instituto de Recursos Geneticos y Productividad, Colegio de Posgraduados, Carretera Mexico-Texcoco Km. 36.5, Montecillo, 56230 Texcoco, Estado de Mexico (Mexico); De la Cruz T, E.; Garcia A, J. M.; Falcon B, T.; Gatica T, M. A. [ININ, Departamento de Biologia, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2009-07-01

    This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R{sub 4}M{sub 18}) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co{sup 60} gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L{sub 25} and L{sub 32} produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

  17. Thermally activated persulfate oxidation of NAPL chlorinated organic compounds: effect of soil composition on oxidant demand in different soil-persulfate systems.

    Science.gov (United States)

    Liu, Jialu; Liu, Zhehua; Zhang, Fengjun; Su, Xiaosi; Lyu, Cong

    2017-04-01

    This study investigates the interaction of persulfate with soil components and chlorinated volatile organic compounds (CVOCs), using thermally activated persulfate oxidation in three soil types: high sand content; high clay content; and paddy field soil. The effect of soil composition on the available oxidant demand and CVOC removal rate was evaluated. Results suggest that the treatment efficiency of CVOCs in soil can be ranked as follows: cis-1,2-dichloroethene > trichloroethylene > 1,2-dichloroethane > 1,1,1-trichloroethane. The reactions of soil components with persulfate, shown by the reduction in soil phase natural organics and mineral content, occurred in parallel with persulfate oxidation of CVOCs. Natural oxidant demand from the reaction of soil components with persulfate exerted a large relative contribution to the total oxidant demand. The main influencing factor in oxidant demand in paddy-soil-persulfate systems was natural organics, rather than mineral content as seen with sand and clay soil types exposed to the persulfate system. The competition between CVOCs and soil components for oxidation by persulfate indicates that soil composition exhibits a considerable influence on the available oxidant demand and CVOC removal efficiency. Therefore, soil composition of natural organics and mineral content is a critical factor in estimating the oxidation efficiency of in-situ remediation systems.

  18. Growth of thermal oxide layers on GaAs and InP in the presence of ammonium heptamolybdate

    International Nuclear Information System (INIS)

    Mittova, I.Ya.; Lavrushina, S.S.; Afonchikova, A.V.

    2004-01-01

    Processes of thermal oxidation of GaAs and InP in the presence of ammonium heptamolybdate were studied using the methods of X-ray fluorescence analysis and IR spectroscopy at temperatures 480-580 Deg C. It was ascertained that introduction of the activator into the system results in accelerated growth of layers on semiconductors due to participation of anionic component of the chemostimulator in oxidation processes. The activator is integrated into the salts formed [ru

  19. Thermal oxidation of seeds for the hydrothermal growth of WO{sub 3} nanorods on ITO glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Chai Yan [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); Department of Mechanical and Material Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras, 43000 Kajang, Selangor (Malaysia); Abdul Razak, Khairunisak, E-mail: khairunisak@usm.my [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia); NanoBiotechnology Research and Innovation (NanoBRI), Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Lockman, Zainovia, E-mail: zainovia@usm.my [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang (Malaysia)

    2015-11-30

    This work reports a simple seed formation method for the hydrothermal growth of tungsten oxide (WO{sub 3}) nanorods. A WO{sub 3} seed layer was prepared by thermal oxidation, where a W-sputtered substrate was heated and oxidized in a furnace. Oxidation temperatures and periods were varied at 400–550 °C and 5–60 min, respectively, to determine an appropriate seed layer for nanorod growth. Thermal oxidation at 500 °C for 15 min was found to produce a seed layer with sufficient crystallinity and good adhesion to the substrate. These properties prevented the seed from peeling off during the hydrothermal process, thereby allowing nanorod growth on the seed. The nanorod film showed better electrochromic behavior (higher current density of − 1.11 and + 0.65 mA cm{sup −2}) than compact film (lower current density of − 0.54 and + 0.28 mA cm{sup −2}). - Highlights: • A simple seed formation method (thermal oxidation) on sputtered W film is reported. • Crystalline seed with good adhesion to substrate is required for nanorod growth. • The appropriate temperature and period for seed formation were 500 °C and 15 min. • WO{sub 3} nanorods exhibited higher electrochromic current density than WO{sub 3} compact film.

  20. Stripping of organic compounds from wastewater as an auxiliary fuel of regenerative thermal oxidizer.

    Science.gov (United States)

    Chang, Meng-Wen; Chern, Jia-Ming

    2009-08-15

    Organic solvents with different volatilities are widely used in various processes and generate air and water pollution problems. In the cleaning processes of electronics industries, most volatile organic compounds (VOCs) are vented to air pollution control devices while most non-volatile organic solvents dissolve in the cleaning water and become the major sources of COD in wastewater. Discharging a high-COD wastewater stream to wastewater treatment facility often disturbs the treatment performance. A pretreatment of the high-COD wastewater is therefore highly desirable. This study used a packed-bed stripping tower in combination with a regenerative thermal oxidizer to remove the COD in the wastewater from a printed circuit board manufacturing process and to utilize the stripped organic compounds as the auxiliary fuel of the RTO. The experimental results showed that up to 45% of the COD could be removed and 66% of the RTO fuel could be saved by the combined treatment system.

  1. The Influence of the Interlayer Distance on the Performance of Thermally Reduced Graphene Oxide Supercapacitors

    Directory of Open Access Journals (Sweden)

    Jun-Hong Lin

    2018-02-01

    Full Text Available In this paper, cationic surfactant cetyltrimethylammonium bromide (CTAB was employed to prevent the restack of the thermally reduce graphene oxide (TRG sheets. A facile approach was demonstrated to effectively enlarge the interlayer distance of the TRG sheets through the ionic interaction between the intercalated CTAB and ionic liquids (ILs. The morphology of the composites and the interaction between the intercalated ionic species were systematically characterized by SEM, SAXS, XRD, TGA, and FTIR. In addition, the performance of the EDLC cells based on these TRG composites was evaluated. It was found that due to the increased interlayer distance (0.41 nm to 2.51 nm that enlarges the accessible surface area for the IL electrolyte, the energy density of the cell can be significantly improved (23.1 Wh/kg to 62.5 Wh/kg.

  2. A thermally robust and thickness independent ferroelectric phase in laminated hafnium zirconium oxide

    Directory of Open Access Journals (Sweden)

    S. Riedel

    2016-09-01

    Full Text Available Ferroelectric properties in hafnium oxide based thin films have recovered the scaling potential for ferroelectric memories due to their ultra-thin-film- and CMOS-compatibility. However, the variety of physical phenomena connected to ferroelectricity allows a wider range of applications for these materials than ferroelectric memory. Especially mixed HfxZr1-xO2 thin films exhibit a broad compositional range of ferroelectric phase stability and provide the possibility to tailor material properties for multiple applications. Here it is shown that the limited thermal stability and thick-film capability of HfxZr1-xO2 can be overcome by a laminated approach using alumina interlayers.

  3. Determination of Polybutadiene Unsaturation Content in Thermal and Thermo-Oxidative Degradation Processes by NMR

    Directory of Open Access Journals (Sweden)

    Farshid Ziaee

    2013-01-01

    Full Text Available The unsaturation content of various polybutadiene (PBD types of 1,4-cis, 1,4-trans and 1,2-vinyl isomers with different molecular weights was investigated. An important parameter for unsaturation content of polybutadiene would be the determination of olefnic and aliphatic contents for three types of isomers. For this purpose, proton and carbon nuclear magnetic resonance spectroscopy methods were employed for determination of 1,4-cis, 1,4-trans and 1,2-vinyl contents. A change of adjustable parameter of NMR software was made for accurate integrals giving better results. The accuracy in calculation of low molecular weight PBD, surface area of chain end group decreased in aliphatic region. Furthermore, the changing of unsaturation content versus time was considered for 1,2-PBD and 1,4-PBD in thermal degradation conditions at 250°C. NMR results showed that during heating, the unsaturation content decreased for 1,2-PBD and was not changed for 1,4-PBD. In fact, the basic factor responsible for changing of unsaturation content in thermal degradation of PBD may be due to the presence of 1,2-vinyl isomer. Finally, changing in unsaturation content versus time was observed for 1,2-PBD and 1,4-PBD in thermo-oxidative degradation conditions at 100°C. The NMR results showed that at extended time, the unsaturation content decreased for 1,4-PBD and was not changed for 1,2-PBD. Moreover, the basic factor for changes in unsaturation content in thermo-oxidative degradation of PBD is due to the presence of 1,4-cis and 1,4-trans isomers.

  4. Nitric oxide synthase modulates CFA-induced thermal hyperalgesia through cytokine regulation in mice.

    Science.gov (United States)

    Chen, Yong; Boettger, Michael K; Reif, Andreas; Schmitt, Angelika; Uçeyler, Nurcan; Sommer, Claudia

    2010-03-02

    Although it has been largely demonstrated that nitric oxide synthase (NOS), a key enzyme for nitric oxide (NO) production, modulates inflammatory pain, the molecular mechanisms underlying these effects remain to be clarified. Here we asked whether cytokines, which have well-described roles in inflammatory pain, are downstream targets of NO in inflammatory pain and which of the isoforms of NOS are involved in this process. Intraperitoneal (i.p.) pretreatment with 7-nitroindazole sodium salt (7-NINA, a selective neuronal NOS inhibitor), aminoguanidine hydrochloride (AG, a selective inducible NOS inhibitor), L-N(G)-nitroarginine methyl ester (L-NAME, a non-selective NOS inhibitor), but not L-N(5)-(1-iminoethyl)-ornithine (L-NIO, a selective endothelial NOS inhibitor), significantly attenuated thermal hyperalgesia induced by intraplantar (i.pl.) injection of complete Freund's adjuvant (CFA). Real-time reverse transcription-polymerase chain reaction (RT-PCR) revealed a significant increase of nNOS, iNOS, and eNOS gene expression, as well as tumor necrosis factor-alpha (TNF), interleukin-1 beta (IL-1beta), and interleukin-10 (IL-10) gene expression in plantar skin, following CFA. Pretreatment with the NOS inhibitors prevented the CFA-induced increase of the pro-inflammatory cytokines TNF and IL-1beta. The increase of the anti-inflammatory cytokine IL-10 was augmented in mice pretreated with 7-NINA or L-NAME, but reduced in mice receiving AG or L-NIO. NNOS-, iNOS- or eNOS-knockout (KO) mice had lower gene expression of TNF, IL-1beta, and IL-10 following CFA, overall corroborating the inhibitor data. These findings lead us to propose that inhibition of NOS modulates inflammatory thermal hyperalgesia by regulating cytokine expression.

  5. Nitric oxide synthase modulates CFA-induced thermal hyperalgesia through cytokine regulation in mice

    Directory of Open Access Journals (Sweden)

    Üçeyler Nurcan

    2010-03-01

    Full Text Available Abstract Background Although it has been largely demonstrated that nitric oxide synthase (NOS, a key enzyme for nitric oxide (NO production, modulates inflammatory pain, the molecular mechanisms underlying these effects remain to be clarified. Here we asked whether cytokines, which have well-described roles in inflammatory pain, are downstream targets of NO in inflammatory pain and which of the isoforms of NOS are involved in this process. Results Intraperitoneal (i.p. pretreatment with 7-nitroindazole sodium salt (7-NINA, a selective neuronal NOS inhibitor, aminoguanidine hydrochloride (AG, a selective inducible NOS inhibitor, L-N(G-nitroarginine methyl ester (L-NAME, a non-selective NOS inhibitor, but not L-N(5-(1-iminoethyl-ornithine (L-NIO, a selective endothelial NOS inhibitor, significantly attenuated thermal hyperalgesia induced by intraplantar (i.pl. injection of complete Freund's adjuvant (CFA. Real-time reverse transcription-polymerase chain reaction (RT-PCR revealed a significant increase of nNOS, iNOS, and eNOS gene expression, as well as tumor necrosis factor-alpha (TNF, interleukin-1 beta (IL-1β, and interleukin-10 (IL-10 gene expression in plantar skin, following CFA. Pretreatment with the NOS inhibitors prevented the CFA-induced increase of the pro-inflammatory cytokines TNF and IL-1β. The increase of the anti-inflammatory cytokine IL-10 was augmented in mice pretreated with 7-NINA or L-NAME, but reduced in mice receiving AG or L-NIO. NNOS-, iNOS- or eNOS-knockout (KO mice had lower gene expression of TNF, IL-1β, and IL-10 following CFA, overall corroborating the inhibitor data. Conclusion These findings lead us to propose that inhibition of NOS modulates inflammatory thermal hyperalgesia by regulating cytokine expression.

  6. The association between soya consumption and serum thyroid-stimulating hormone concentrations in the Adventist Health Study-2.

    Science.gov (United States)

    Tonstad, Serena; Jaceldo-Siegl, Karen; Messina, Mark; Haddad, Ella; Fraser, Gary E

    2016-06-01

    Consumers may choose soya foods as healthful alternatives to animal products, but concern has arisen that eating large amounts of soya may adversely affect thyroid function. The present study aimed to examine the association between soya food consumption and serum thyroid-stimulating hormone (TSH) concentrations in North American churchgoers belonging to the Seventh-day Adventist denomination that encourages vegetarianism. Participants completed six repeated 24 h dietary recalls within a 6-month period. Soya protein and soya isoflavone intakes were estimated, and their relationships to TSH concentrations measured at the end of 6 months were calculated using logistic regression analyses. Calibration sub-study of the Adventist Health Study-2. Women (n 548) and men (n 295) who were not taking thyroid medications. In men, age and urinary iodine concentrations were associated with high serum TSH concentrations (>5 mIU/l), while among women White ethnicity was associated with high TSH. In multivariate models adjusted for age, ethnicity and urinary iodine, soya isoflavone and protein intakes were not associated with high TSH in men. In women higher soya isoflavone consumption was associated with higher TSH, with an adjusted odds ratio (highest v. lowest quintile) of 4·17 (95 % CI 1·73, 10·06). Likewise, women with high consumption of soya protein (midpoint of highest quintile, 11 g/d) v. low consumption (midpoint of lowest quintile, 0 g/d) carried increased odds of high TSH (OR=2·69; 95 % CI 1·34, 5·30). In women high consumption of soya was associated with elevated TSH concentrations. No associations between soya intake and TSH were found in men.

  7. Effect of soya lecithin on the enzymatic system of the white-rot fungi Anthracophyllum discolor.

    Science.gov (United States)

    Bustamante, M; González, M E; Cartes, A; Diez, M C

    2011-01-01

    The present work optimized the initial pH of the medium and the incubation temperature for ligninolytic enzymes produced by the white-rot fungus Anthracophyllum discolor. Additionally, the effect of soya lecithin on mycelial growth and the production of ligninolytic enzymes in static batch cultures were evaluated. The critical micelle concentration of soya lecithin was also studied by conductivity. The effects of the initial pH (3, 4, and 5) and incubation temperature (20, 25, and 30°C) on different enzymatic activities revealed that the optimum conditions to maximize ligninolytic activity were 26°C and pH 5.5 for laccase and manganese peroxidase (MnP) and 30°C and pH 5.5 for manganese-independent peroxidase (MiP). Under these culture conditions, the maximum enzyme production was 10.16, 484.46, and 112.50 U L(-1) for laccase, MnP, and manganese-independent peroxidase MiP, respectively. During the study of the effect of soya lecithin on A. discolor, we found that the increase in soya lecithin concentration from 0 to 10 g L(-1) caused an increase in mycelial growth. On the other hand, in the presence of soya lecithin, A. discolor produced mainly MnP, which reached a maximum concentration of 30.64 ± 4.61 U L(-1) after 25 days of incubation with 1 g L(-1) of the surfactant. The other enzymes were produced but to a lesser extent. The enzymatic activity of A. discolor was decreased when Tween 80 was used as a surfactant. The critical micelle concentration of soya lecithin calculated in our study was 0.61 g L(-1).

  8. New Triterpenoid Saponins from Green Vegetable Soya Beans and Their Anti-Inflammatory Activities.

    Science.gov (United States)

    Lan, Xiuhua; Deng, Kejun; Zhao, Jianping; Chen, Yiyi; Xin, Xuhui; Liu, Yanli; Khan, Ikhlas A; Yang, Shilin; Wang, Taoyun; Xu, Qiongming

    2017-12-20

    Ten compounds were isolated and identified from green vegetable soya beans, of which five are new triterpenoid saponins (1-5) and five are known compounds (6-10). The chemical structures of the five triterpenoid saponins (1-5) were elucidated to be 3β,24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 1; 3β,24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-O-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 2; 22-keto-3β,24-dihydroxy oleanane-12-ene 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-O-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 3; 3β,22β,24-trihydroxy oxyolean-18(19)-ene-29-acid 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 4; and punicanolic acid 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 5 from the spectroscopic data (IR, GTC/FID, HR-ESI-MS, and 1D and 2D NMR). The nitric oxide release inhibitions of compounds 1-10 in LPS-stimulated RAW264.7 cells were evaluated, and the data suggested that compounds 1, 2, and 5 might possess moderate anti-inflammatory activities, with IC 50 values of 18.8, 16.1, and 13.2 μM, respectively.

  9. A Numerical Investigation of the Thermal Stresses of a Planar Solid Oxide Fuel Cell

    Directory of Open Access Journals (Sweden)

    Paulina Pianko-Oprych

    2016-09-01

    Full Text Available A typical operating temperature of a solid oxide fuel cell (SOFC is quite high above 750 °C and affects the thermomechanical behavior of the cell. Thermal stresses may cause microstructural instability and sub-critical cracking. Therefore, a joint analysis by the computational fluid dynamics (CFD and computational structural mechanics based on the finite element method (FEM was carried out to analyze thermal stresses in a planar SOFC and to predict potential failure locations in the cell. A full numerical model was based on the coupling of thermo-fluid model with the thermo-mechanical model. Based on a temperature distribution from the thermo-fluid model, stress distribution including the von Mises stress, shear stress as well as the operating principal stress were derived in the thermo-mechanical model. The FEM calculations were performed under different working conditions of the planar SOFC. The highest total stress was noticed at the lower operating voltage of 0.3 V, while the lowest total stress was determined at the voltage of 0.7 V. The obtained stress distributions allowed a better understanding of details of internal processes occurring within the SOFC and provided helpful guidance in the optimization of a new SOFC design.

  10. Numerical investigation of damage protective oxide mechanisms in thermal barrier system for aeronautical turbine blade.

    Directory of Open Access Journals (Sweden)

    khelifa hocine

    2015-03-01

    Full Text Available The choice of a material for a given application requires insuring a good durability in its conditions of employment, in particular environmental. It is especially true for the systems destined to work in corrosive hot atmospheres. For it, the knowledge and the understanding of the corrosion phenomena, oxidization, ageing and damage are indispensable in order to anticipate the life period of the structures and to propose the adapted protective solutions. The study of the corrosion in high temperature is therefore a greatly interdisciplinary topic, into the interface of the physico-chemistry, metallic and ceramic materials and mechanics. We propose in this work a finite element method for the simulation of EBPVD TBCs spallation. Our studies concern one of several systems that we call thermal barrier coatings, which are a Composite materials deposited in layers on the hot components to isolate them chemically and thermally at high temperatures. This is the last operational technology adapted on aircraft engines but it is still studied and not fully exploited.This comprehensive article describes the systems currently used and the problem of interaction between mechanical and environment in the turbine.

  11. Nitrogen oxides emissions from thermal power plants in china: current status and future predictions.

    Science.gov (United States)

    Tian, Hezhong; Liu, Kaiyun; Hao, Jiming; Wang, Yan; Gao, Jiajia; Qiu, Peipei; Zhu, Chuanyong

    2013-10-01

    Increasing emissions of nitrogen oxides (NOx) over the Chinese mainland have been of great concern due to their adverse impacts on regional air quality and public health. To explore and obtain the temporal and spatial characteristics of NOx emissions from thermal power plants in China, a unit-based method is developed. The method assesses NOx emissions based on detailed information on unit capacity, boiler and burner patterns, feed fuel types, emission control technologies, and geographical locations. The national total NOx emissions in 2010 are estimated at 7801.6 kt, of which 5495.8 kt is released from coal-fired power plant units of considerable size between 300 and 1000 MW. The top provincial emitter is Shandong where plants are densely concentrated. The average NOx-intensity is estimated at 2.28 g/kWh, markedly higher than that of developed countries, mainly owing to the inadequate application of high-efficiency denitrification devices such as selective catalytic reduction (SCR). Future NOx emissions are predicted by applying scenario analysis, indicating that a reduction of about 40% by the year 2020 can be achieved compared with emissions in 2010. These results suggest that NOx emissions from Chinese thermal power plants could be substantially mitigated within 10 years if reasonable control measures were implemented effectively.

  12. Thermal-fatigue and oxidation resistance of cobalt-modified Udimet 700 alloy

    International Nuclear Information System (INIS)

    Bizon, P.T.; Barrow, B.J.

    1986-04-01

    Comparative thermal-fatigue and oxidation resistances of cobalt-modified wrought Udimet 700 alloy (obtained by reducing the cobalt level by direct substitution of nickel) were determined from fluidized-bed tests. Bed temperatures were 1010 and 288 C (1850 and 550 C) for the first 5500 symmetrical 6-min cycles. From cycle 5501 to the 14000-cycle limit of testing, the heating bed temperature was increased to 1050 C (1922 F). Cobalt levels between 0 and 17 wt% were studied in both the bare and NiCrAlY overlay coated conditions. A cobalt level of about 8 wt% gave the best thermal-fatigue life. The conventional alloy specification is for 18.5% cobalt, and hence, a factor of 2 in savings of cobalt could be achieved by using the modified alloy. After 13500 cycles, all bare cobalt-modified alloys lost 10 to 13 percent of their initial weight. Application of the NiCrAlY overlay coating resulted in weight losses of 1/20 to 1/100 of that of the corresponding bare alloy

  13. Radio-frequency magnetron sputtering and wet thermal oxidation of ZnO thin film

    International Nuclear Information System (INIS)

    Liu, H. F.; Chua, S. J.; Hu, G. X.; Gong, H.; Xiang, N.

    2007-01-01

    The authors studied the growth and wet thermal oxidation (WTO) of ZnO thin films using a radio-frequency magnetron sputtering technique. X-ray diffraction reveals a preferred orientation of [1010]ZnO(0002)//[1120]Al 2 O 3 (0002) coexisted with a small amount of ZnO (1011) and ZnO (1013) crystals on the Al 2 O 3 (0001) substrate. The ZnO (1011) and ZnO (1013) crystals, as well as the in-plane preferred orientation, are absent from the growth of ZnO on the GaAs(001) substrate. WTO at 550 deg. C improves the crystalline and the photoluminescence more significantly than annealing in air, N 2 and O 2 ambient; it also tends to convert the crystal from ZnO (1011) and ZnO (1013) to ZnO (0002). The evolution of the photoluminescence upon WTO and annealing reveals that the green and orange emissions, centered at 520 and 650 nm, are likely originated from oxygen vacancies and oxygen interstitials, respectively; while the 420 nm emission, which is very sensitive to the postgrowth thermal processing regardless of the substrate and the ambient gas, is likely originated from the surface-state related defects

  14. Morphology, Mechanical and Thermal Properties of Thermoplastic Polyurethane Containing Reduced Graphene Oxide and Graphene Nanoplatelets.

    Science.gov (United States)

    Strankowski, Michał; Korzeniewski, Piotr; Strankowska, Justyna; A S, Anu; Thomas, Sabu

    2018-01-06

    Polyurethane/graphene nanocomposites were synthesized using commercial thermoplastic polyurethane (TPU, Apilon 52DE55), and two types of graphene derivatives: graphene nanoplatelets (GNP) and reduced graphene oxide (RGO). Fourier Transformation Infrared Spectroscopy Fourier Transformation Infrared Spectroscopy (FTIR) spectroscopy, TEM, and SEM microscopy and XRD techniques were used to chemically and structurally characterize GNP and RGO nanofillers. The properties of the new TPU nanocomposite materials were studied using thermal analysis techniques (Dynamical Mechanical Analysis (DMA), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TG)) to describe the influence of graphene nanofillers on polyurethane matrix. Our investigation describes the comparison of two types of graphene derivatives, commercial one (GNP) and synthesized (RGO) on thermoplastic polyurethanes. These nanofillers provides opportunities to achieve compatibility with the TPU matrix. The property enhancements are attributed commonly to high aspect ratio of graphene nanoplatelets and filler-polymer interactions at the interface. The obtained nanocomposites exhibit higher thermal and mechanical properties due to the good dispersion of both nanofillers into TPU matrix. It was found that the addition of 2 wt % of the nanofiller could lead to a significant reinforcement effect on the TPU matrix. Also, with high content of nanofiller (GNP and RGO), the Payne effect was observed.

  15. Morphology, Mechanical and Thermal Properties of Thermoplastic Polyurethane Containing Reduced Graphene Oxide and Graphene Nanoplatelets

    Directory of Open Access Journals (Sweden)

    Michał Strankowski

    2018-01-01

    Full Text Available Polyurethane/graphene nanocomposites were synthesized using commercial thermoplastic polyurethane (TPU, Apilon 52DE55, and two types of graphene derivatives: graphene nanoplatelets (GNP and reduced graphene oxide (RGO. Fourier Transformation Infrared Spectroscopy Fourier Transformation Infrared Spectroscopy (FTIR spectroscopy, TEM, and SEM microscopy and XRD techniques were used to chemically and structurally characterize GNP and RGO nanofillers. The properties of the new TPU nanocomposite materials were studied using thermal analysis techniques (Dynamical Mechanical Analysis (DMA, Differential Scanning Calorimetry (DSC, Thermogravimetric Analysis (TG to describe the influence of graphene nanofillers on polyurethane matrix. Our investigation describes the comparison of two types of graphene derivatives, commercial one (GNP and synthesized (RGO on thermoplastic polyurethanes. These nanofillers provides opportunities to achieve compatibility with the TPU matrix. The property enhancements are attributed commonly to high aspect ratio of graphene nanoplatelets and filler–polymer interactions at the interface. The obtained nanocomposites exhibit higher thermal and mechanical properties due to the good dispersion of both nanofillers into TPU matrix. It was found that the addition of 2 wt % of the nanofiller could lead to a significant reinforcement effect on the TPU matrix. Also, with high content of nanofiller (GNP and RGO, the Payne effect was observed.

  16. A Numerical Investigation of the Thermal Stresses of a Planar Solid Oxide Fuel Cell

    Science.gov (United States)

    Pianko-Oprych, Paulina; Zinko, Tomasz; Jaworski, Zdzisław

    2016-01-01

    A typical operating temperature of a solid oxide fuel cell (SOFC) is quite high above 750 °C and affects the thermomechanical behavior of the cell. Thermal stresses may cause microstructural instability and sub-critical cracking. Therefore, a joint analysis by the computational fluid dynamics (CFD) and computational structural mechanics based on the finite element method (FEM) was carried out to analyze thermal stresses in a planar SOFC and to predict potential failure locations in the cell. A full numerical model was based on the coupling of thermo-fluid model with the thermo-mechanical model. Based on a temperature distribution from the thermo-fluid model, stress distribution including the von Mises stress, shear stress as well as the operating principal stress were derived in the thermo-mechanical model. The FEM calculations were performed under different working conditions of the planar SOFC. The highest total stress was noticed at the lower operating voltage of 0.3 V, while the lowest total stress was determined at the voltage of 0.7 V. The obtained stress distributions allowed a better understanding of details of internal processes occurring within the SOFC and provided helpful guidance in the optimization of a new SOFC design. PMID:28773935

  17. Thermal aging effects on the microstructure, oxidation behavior, and mechanical properties of as-cast nickel aluminide alloys

    Science.gov (United States)

    Lee, Dongyun

    The thermal aging effects on the microstructure, oxidation behavior at 900° and 1100°C, and mechanical properties of IC221M (Ni3Al based intermetallic alloy, ASTM A1002-99) were investigated. The microstructure consists of dendritic arms of the gamma (nickel solid solution) phase containing cube-shape gamma' (Ni3Al precipitates. The interdendritic regions are mostly gamma' (Ni3Al with up to 8 vol.% gamma + Ni5Zr eutectic constituents. Thermal aging effects on the microstructures and how microsegregation affects the oxidation behavior were examined. Four primary changes in the microstructures were observed: (1) there is considerable homogenization of the cast microstructures with aging, (2) the volume fraction of gamma' increases with aging time and temperature, (3) the gamma' phase coarsens, and (4) the volume fraction of the gamma + Ni5Zr eutectic constituents decreases. During the initial stages of oxidation at 900°C, surface oxides form along the microsegregation patterns, revealing the cast microstructures. The first oxide to form is mostly NiO with small amounts of Cr2O 3, ZrO2, NiCr2O4, and theta-Al 2O3. Initial oxidation occurs primarily in the interdendritic regions due to microsegregation of alloying elements during casting. With further aging, the predominant surface oxides become NiO and NiAl2O 4 spinel, with a continuous film of alpha-Al2O3 forming immediately beneath them. Although these oxides are constrained to the near surface region, other oxides penetrate to greater depths, facilitated by oxidation of the gamma + Ni5Zr eutectic constituents. These oxides appear in the microstructure as long, thin spikes of ZrO2 surrounded by a sheath of Al2O3. They can penetrate to depths greater than 10 times that of the continuous surface oxide. The oxidation behavior at 1100°C is similar to that at 900°C, but the oxidation kinetics are faster, NiO dominates at all aging periods, and the surface oxides do not adhere to the matrix meaning that a protective

  18. Soya protein antibodies in man: their occurrence and possible relevance in coeliac disease.

    Science.gov (United States)

    Haeney, M R; Goodwin, B J; Barratt, M E; Mike, N; Asquith, P

    1982-01-01

    Circulating antibodies to soya-derived protein antigens have been measured in patients with duodenitis, Crohn's disease, ulcerative colitis and coeliac disease. Significantly raised antibody titres were found frequently in the coeliac group, particularly those patients showing a suboptimal response to a gluten-free diet, but rarely in subjects with other gastrointestinal diseases. Antisoya activity was not necessarily accompanied by antibodies to other common dietary antigens. We suggest that some coeliacs may have an associated dietary soya sensitivity which could adversely influence their response to gluten withdrawal. PMID:7040491

  19. Inhibición de los contaminantes del tempeh de soya

    OpenAIRE

    Mejías, E.; Delgado, R.; Silveira, I.; Lafargue, D.; Cárdenas, E.

    2008-01-01

    Se evaluó el efecto de diferentes especias o condimentos sobre la calidad microbiológica del tempeh y la posible acción inhibidora de sus contaminantes. El tempeh se obtuvo a partir de frijol de soya el cual se sometió a los procesos de cocción, escurrimiento y fermentación. A continuación se procedió a incorporar los condimentos ensayados en dos proporciones por separado a la soya fresca antes de su inoculación con la cepa R. oligosporus, se mezclaron bien y se someti...

  20. DISEÑO Y DESARROLLO DE QUESO FRESCO ENRIQUECIDO CON ACEITE DE SOYA

    OpenAIRE

    Tuesta Ch., Tarsila; Universidad Nacional de Ingeniería, Lima, Perú.; Vargas M., Jorge; Universidad Nacional Agraria La Molina, Lima, Perú.; García G., Gilberto; Universidad Nacional de Ingeniería, Lima, Perú.; Ureña P., Milber; Docente Asociado, D.I.A.P.A. Univ. Nac. Agraria La Molina; Neira M., Enrique; Universidad Nacional de Ingeniería, Lima, Perú.

    2015-01-01

    El objetivo fue obtener un queso fresco enriquecido con aceite de soya, con aceptabilidad sensorial y rico en grasas poliinsaturadas, principalmente los ácidos grasos esenciales linoleico y linolénico. Como materias primas se utilizó: leche fresca descremada de vacas de raza Holstein y aceite de soya. El contenido de ácidos grasos poliinsaturados, que contiene el queso fresco elaborado con leche entera se elevó de 5,01% a 54,83% al elaborarlo con leche descremada enriquecida con 2% de aceite ...

  1. Enhanced performance of thermal-assisted electron field emission based on barium oxide nanowire

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Yunkang [Department of Mathematics and Physics, Nanjing Institute of technology, Nanjing, 211167 (China); Chen, Jing, E-mail: chenjingmoon@gmail.com [School of Electronic Science & Engineering, Southeast University, Nanjing, 210096 (China); Zhang, Yuning; Zhang, Xiaobing; Lei, Wei; Di, Yunsong [School of Electronic Science & Engineering, Southeast University, Nanjing, 210096 (China); Zhang, Zichen, E-mail: zz241@ime.ac.cn [Integrated system for Laser applications Group, Institute of Microelectronics of Chinese Academy of Sciences, 100029, Beijing (China)

    2017-02-28

    Highlights: • A possible mechanism for thermal-assisted electric field was demonstrated. • A new path for the architecture of the novel nanomaterial and methodology for its potential application in the field emission device area was provided. • The turn-on field, the threshold field and the field emission current density were largely related to the temperature of the cathode. • The relationship between the work function of emitter material and the temperature of emitter was found. - Abstract: In this paper, thermal-assisted field emission properties of barium oxide (BaO) nanowire synthesized by a chemical bath deposition method were investigated. The morphology and composition of BaO nanowire were characterized by field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SED), X-ray diffraction (XRD), and energy dispersive X-ray spectrometer (EDX) respectively. The turn-on field, threshold field and the emission current density could be affected relatively due to the thermal-assisted effect when the electric field was applied, in the meanwhile, the turn-on field for BaO nanowire was measured to be decreased from 1.12 V/μm to 0.66 V/μm when the temperature was raised from 293 K to 593 K, whereas for the threshold field was found to decrease from 3.64 V/μm to 2.12 V/μm. The improved performance was demonstrated due to the reduced work function of the BaO nanowire as the agitation temperature increasing, leading to the higher probability of electrons tunneling through the energy barrier and enhancement of the field emission properties of BaO emitters.

  2. Chemical and Radiochemical Composition of Thermally Stabilized Plutonium Oxide from the Plutonium Finishing Plant Considered as Alternate Feedstock for the Mixed Oxide Fuel Fabrication Facility

    International Nuclear Information System (INIS)

    Tingey, Joel M.; Jones, Susan A.

    2005-01-01

    Eighteen plutonium oxide samples originating from the Plutonium Finishing Plant (PFP) on the Hanford Site were analyzed to provide additional data on the suitability of PFP thermally stabilized plutonium oxides and Rocky Flats oxides as alternate feedstock to the Mixed Oxide Fuel Fabrication Facility (MFFF). Radiochemical and chemical analyses were performed on fusions, acid leaches, and water leaches of these 18 samples. The results from these destructive analyses were compared with nondestructive analyses (NDA) performed at PFP and the acceptance criteria for the alternate feedstock. The plutonium oxide materials considered as alternate feedstock at Hanford originated from several different sources including Rocky Flats oxide, scrap from the Remote Mechanical C-Line (RMC) and the Plutonium Reclamation Facility (PRF), and materials from other plutonium conversion processes at Hanford. These materials were received at PFP as metals, oxides, and solutions. All of the material considered as alternate feedstock was converted to PuO2 and thermally stabilized by heating the PuO2 powder at 950 C in an oxidizing environment. The two samples from solutions were converted to PuO2 by precipitation with Mg(OH)2. The 18 plutonium oxide samples were grouped into four categories based on their origin. The Rocky Flats oxide was divided into two categories, low- and high-chloride Rocky Flats oxides. The other two categories were PRF/RMC scrap oxides, which included scrap from both process lines and oxides produced from solutions. The two solution samples came from samples that were being tested at Pacific Northwest National Laboratory because all of the plutonium oxide from solutions at PFP had already been processed and placed in 3013 containers. These samples originated at the PFP and are from plutonium nitrate product and double-pass filtrate solutions after they had been thermally stabilized. The other 16 samples originated from thermal stabilization batches before canning at

  3. Effect of Oxide Nanoparticles on Thermal and Mechanical Properties of Electrospun Separators for Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Marco Zaccaria

    2012-01-01

    Full Text Available This study reports the fabrication and characterization of poly(ethylene oxide (PEO and poly(vinylidenefluoride-co-chlorotrifluoroethylene (PVDF-CTFE nanofibrous separators for lithium-ion batteries loaded with different amounts of fumed-silica and tin oxide nanoparticles. Membrane morphological characterization (SEM, TEM showed the presence of good-quality nanofibres containing nanoparticles. Thermal degradation and membrane mechanical properties were also investigated, and a remarkable effect of nanoparticle addition on membrane mechanical properties was found. In particular, PEO membranes were strengthened by the addition of metal oxide, whereas PVDF-CTFE membranes acquired ductility.

  4. Sulfur-oxidizing chemolithotrophic proteobacteria dominate the microbiota in high arctic thermal springs on Svalbard.

    Science.gov (United States)

    Reigstad, Laila Johanne; Jorgensen, Steffen Leth; Lauritzen, Stein-Erik; Schleper, Christa; Urich, Tim

    2011-09-01

    The thermal springs Trollosen and Fisosen, located on the High Arctic archipelago Svalbard, discharge saline groundwaters rich in hydrogen sulfide and ammonium through a thick layer of permafrost. Large amounts of biomass that consist of filamentous microorganisms containing sulfur granules, as analyzed with energy dispersive X-ray analysis, were found in the outflow. Prokaryotic 16S rRNA gene libraries and quantitative polymerase chain reaction (qPCR) analyses reported bacteria of the γ- and ɛ-proteobacterial classes as the dominant organisms in the filaments and the planktonic fractions, closely related to known chemolithoautotrophic sulfur oxidizers (Thiotrix and Sulfurovum). Archaea comprised ∼1% of the microbial community, with the majority of sequences affiliated with the Thaumarchaeota. Archaeal and bacterial genes coding for a subunit of the enzyme ammonia monooxygenase (amoA) were detected, as well as 16S rRNA genes of Nitrospira, all of which is indicative of potential complete nitrification in both springs. 16S rRNA sequences related to methanogens and methanotrophs were detected as well. This study provides evidence that the microbial communities in Trollosen and Fisosen are sustained by chemolithotrophy, mainly through the oxidation of reduced sulfur compounds, and that ammonium and methane might be minor, additional sources of energy and carbon.

  5. Direct chemical oxidation: a non-thermal technology for the destruction of organic wastes

    Energy Technology Data Exchange (ETDEWEB)

    Balazs, G.B.; Cooper, J. F.; Lewis, P. R.; Adamson, M. G.

    1998-02-01

    Direct Chemical Oxidation (DCO) is a non-thermal, ambient pressure, aqueous-based technology for the oxidative destruction of the organic components of hazardous or mixed waste streams. The process has been developed for applications in waste treatment and chemical demilitarization and decontamination at LLNL since 1992, and is applicable to the destruction of virtually all solid or liquid organics, including: chlorosolvents, oils and greases, detergents, organic-contaminated soils or sludges, explosives, chemical and biological warfare agents, and PCB's. [1-15] The process normally operates at 80-100 C, a heating requirement which increases the difficulty of surface decontamination of large objects or, for example, treatment of a wide area contaminated soil site. The driver for DCO work in FY98 was thus to investigate the use of catalysts to demonstrate the effectiveness of the technology for organics destruction at temperatures closer to ambient. In addition, DCO is at a sufficiently mature stage of development that technology transfer to a commercial entity was a logical next step, and was thus included in FY98 tasks.

  6. Tribological performance of titanium samples oxidized by fs-laser radiation, thermal heating, or electrochemical anodization

    Science.gov (United States)

    Kirner, S. V.; Slachciak, N.; Elert, A. M.; Griepentrog, M.; Fischer, D.; Hertwig, A.; Sahre, M.; Dörfel, I.; Sturm, H.; Pentzien, S.; Koter, R.; Spaltmann, D.; Krüger, J.; Bonse, J.

    2018-04-01

    Commercial grade-1 titanium samples (Ti, 99.6%) were treated using three alternative methods, (i) femtosecond laser processing, (ii) thermal heat treatment, and (iii) electrochemical anodization, respectively, resulting in the formation of differently conditioned superficial titanium oxide layers. The laser processing (i) was carried out by a Ti:sapphire laser (pulse duration 30 fs, central wavelength 790 nm, pulse repetition rate 1 kHz) in a regime of generating laser-induced periodic surface structures (LIPSS). The experimental conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning setup for the processing of several square-millimeters large surface areas covered homogeneously by these nanostructures. The differently oxidized titanium surfaces were characterized by optical microscopy, micro Raman spectroscopy, variable angle spectroscopic ellipsometry, and instrumented indentation testing. The tribological performance was characterized in the regime of mixed friction by reciprocating sliding tests against a sphere of hardened steel in fully formulated engine oil as lubricant. The specific tribological performance of the differently treated surfaces is discussed with respect to possible physical and chemical mechanisms.

  7. Effect of cuprous oxide with different sizes on thermal and combustion behaviors of unsaturated polyester resin.

    Science.gov (United States)

    Hou, Yanbei; Hu, Weizhao; Gui, Zhou; Hu, Yuan

    2017-07-15

    Cuprous oxide (Cu 2 O) as an effective catalyst has been applied to enhance the fire safety of unsaturated polyester resin (UPR), but the particle size influence on combustion behaviors has not been previously reported. Herein, the UPR/Cu 2 O composites (metal oxide particles with average particle-size of 10, 100, and 200nm) were successfully synthesized by thermosetting process. The effects of Cu 2 O with different sizes on thermostability and combustion behaviors of UPR were characterized by TGA, MCC, TG-IR, FTIR, and SSTF. The results revel that the addition of Cu 2 O contributes to sufficient decomposition of oxygen-containing compounds, which is beneficial to the release of nontoxic compounds. The smallest-sized Cu 2 O performs the excellent catalytic decomposition effect and promotes the complete combustion of UPR, which benefits the enhancement of fire safety. While the other additives retard pyrolysis process and yield more char residue, and thus the flame retardancy of UPR composites was improved. Therefore, catalysis plays a major role for smaller-sized particles during thermal decomposition of matrix, while flame retarded effect became gradual distinctly for the larger-sized additives. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Growth and structure of rapid thermal silicon oxides and nitroxides studied by spectroellipsometry and Auger electron spectroscopy

    Science.gov (United States)

    Gonon, N.; Gagnaire, A.; Barbier, D.; Glachant, A.

    1994-11-01

    Rapid thermal oxidation of Czochralski-grown silicon in either O2 or N2O atmospheres have been studied using spectroellipsometry and Auger electron spectroscopy. Multiwavelength ellipsometric data were processed in order to separately derive the thickness and refractive indexes of rapid thermal dielectrics. Results revealed a significant increase of the mean refractive index as the film thickness falls below 20 nm for both O2 or N2O oxidant species. A multilayer structure including an about 0.3-nm-thick interfacial region of either SiO(x) or nitroxide in the case of O2 and N2O growth, respectively, followed by a densified SiO2 layer, was found to accurately fit the experimental data. The interfacial region together with the densified state of SiO2 close to the interface suggest a dielectric structure in agreement with the continuous random network model proposed for classical thermal oxides. Auger electron spectroscopy analysis confirmed the presence of noncrystalline Si-Si bonds in the interfacial region, mostly in the case of thin oxides grown in O2. It was speculated that the initial fast growth regime was due to a transient oxygen supersaturation in the interfacial region. Besides, the self-limiting growth in N2O was confirmed and explained in agreement with several recently published data, by the early formation of a very thin nitride or oxynitride membrane in the highly densified oxide beneath the interface. The beneficial effect of direct nitrogen incorporation by rapid thermal oxidation in N2O instead of O2 for the electrical behavior of metal-oxide-semiconductor capacitors is likely a better SiO2/Si lattice accommodation through the reduction of stresses and Si-Si bonds in the interfacial region of the dielectric.

  9. Evaluation of Thermal Oxidative Aging Effect on the Rheological Performance of Modified Asphalt Binders

    Science.gov (United States)

    Zhu, Cheng

    Modified asphalt binder, which is combined by base binder and additive modifier, has been implemented in pavement industry for more than 30 years. Recently, the oxidative aging mechanism of asphalt binder has been studied for several decades, and appreciable finding results of asphalt binder aging mechanism were achieved from the chemistry and rheological performance aspects. However, most of these studies were conducted with neat binders, the research of aging mechanism of modified asphalt binder was limited. Nowadays, it is still highly necessary to clarify how the asphalt binder aging happens with the modified asphalt binder, what is the effect of the different modifiers (additives) on the binder aging process, how the rheological performance changes under the thermal oxidative aging conditions and so on. The objective of this study was to investigate the effect of isothermal oxidative aging conditions on the rheological performance change of the modified and controlled asphalt binders. There were totally 14 different sorts of asphalt binders had been aged in the PAV pans in the air-force drafted ovens at 50°C, 60°C and 85°C for 0.5 day to 240 days. The Fourier-Transform Infrared Spectroscopy (FT-IR) and Dynamic Shear Rheometer (DSR) were used to perform the experiments. The analysis of rheological indices (Low shear viscosity-LSV, Crossover modulus-G*c, Glover-Rowe Parameter-G-R, DSR function-DSR Fn) as a function of carbonyl area (CA) was conducted. With the SBS modification, both of the hardening susceptibility of the rheological index-LSV and G-R decreases compared with the corresponding base binder. The TR increased the hardening susceptibility of all the rheological indexes. While for the G*c, SBS increases the slope of the most modified asphalt binders except A and B_TR_X series binders. The multiple linear regression statistical analysis results indicate that the oxidative aging conditions play an important role on the CA, and rheological performance

  10. Structural and microstructural changes in the zirconium-indium mixed oxide system during the thermal treatment

    Science.gov (United States)

    Štefanić, G.; Štefanić, I. I.; Musić, S.; Ivanda, M.

    2011-05-01

    The zirconium-indium mixed oxide systems on both the zirconium- and the indium-rich side of the concentration range were prepared by co-precipitation from aqueous solutions of the corresponding salts, followed by washing and heat-treatment. The thermal behavior (up to 1000 °C) of the dried samples was examined by X-ray powder diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectrometry, differential thermal analysis and thermogravimetric measurements. The obtained results show that the increase in the amount of the second phase causes an increase of both the crystallization temperature of the amorphous precursors of ZrO 2, from 435 °C (0 mol.% of InO 1.5) to 476 °C (˜62 mol.% of InO 1.5), and of the topotactic transition temperature of cubic In(OH) 3 to cubic In 2O 3, from 259 °C (0 mol.% of ZrO 2) to 290 °C (˜25 mol.% of ZrO 2). The amorphous precursors of ZrO 2 phase exhibit an extended capability to incorporate In 3+ ions (more than 60 mol.%). With a rise in temperature the maximum solubility of In 3+ ions in the ZrO 2 lattice decreases from ˜55 mol.% in the crystallization products obtained after calcination at 400 °C to ˜10 mol.% after calcination at 1000 °C. The results of phase analysis indicate that the incorporation of In 3+ ions partially stabilized both the tetragonal and cubic ZrO 2 polymorphs. The maximum solubility of Zr 4+ ions in the starting In(OH) 3 lattice was estimated at ˜10 mol.%. Thermal treatment causes a small increase of Zr 4+ ion solubility limits, estimated at ˜15 mol.% in the cubic In 2O 3 lattice after calcination at 1000 °C. Precise lattice parameter measurements, by using Le Bail refinements of the powder diffraction patterns with added silicon as an internal standard, show that the incorporation of In 3+ ions caused a very small decrease of the cubic ZrO 2 lattice, while the incorporation of Zr 4+ ions had a negligible

  11. Tempol improves cutaneous thermal hyperemia through increasing nitric oxide bioavailability in young smokers

    Science.gov (United States)

    Fujii, Naoto; Brunt, Vienna E.

    2014-01-01

    We recently found that young cigarette smokers display cutaneous vascular dysfunction relative to nonsmokers, which is partially due to reduced nitric oxide (NO) synthase (NOS)-dependent vasodilation. In this study, we tested the hypothesis that reducing oxidative stress improves NO bioavailability, enhancing cutaneous vascular function in young smokers. Ten healthy young male smokers, who had smoked for 6.3 ± 0.7 yr with an average daily consumption of 9.1 ± 0.7 cigarettes, were tested. Cutaneous vascular conductance (CVC) during local heating to 42°C at a rate of 0.1°C/s was evaluated as laser-Doppler flux divided by mean arterial blood pressure and normalized to maximal CVC, induced by local heating to 44°C plus sodium nitroprusside administration. We evaluated plateau CVC during local heating, which is known to be highly dependent on NO, at four intradermal microdialysis sites with 1) Ringer solution (control); 2) 10 μM 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (tempol), a superoxide dismutase mimetic; 3) 10 mM Nω-nitro-l-arginine (l-NNA), a nonspecific NOS inhibitor; and 4) a combination of 10 μM tempol and 10 mM l-NNA. Tempol increased plateau CVC compared with the Ringer solution site (90.0 ± 2.3 vs. 77.6 ± 3.9%maximum, P = 0.028). Plateau CVC at the combination site (56.8 ± 4.5%maximum) was lower than the Ringer solution site (P tempol effect was exclusively NO dependent. These data suggest that in young smokers, reducing oxidative stress improves cutaneous thermal hyperemia to local heating by enhancing NO production. PMID:24682395

  12. The influence of natural tocopherols during thermal oxidation of refined and partially hydrogenated soybean oils

    Directory of Open Access Journals (Sweden)

    Barrera-Arellano, D.

    2005-03-01

    Full Text Available Samples of refined and partially hydrogenated soybean oils, with iodine values between 60 and 130, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C (during for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds and tocopherols. The relation of iodine value to the formation of dimers and polymers and the role of originally present tocopherols in the protection of fats and oils against thermal degradation was verified. The degradation curves for tocopherols showed that α and γ -tocopherols were destroyed faster than β and δ -tocopherols. In addition, the degradation rate of tocopherols was greater in the more saturated fats. The formation of dimers and polymers was greater in the oil than in the hydrogenated samples and in the samples treated with aluminium oxide with respect to the original, untreated samples.Muestras de aceites refinados y parcialmente hidrogenados de soja, con índices de yodo entre 60 y 130, tratadas o no con óxido de aluminio para eliminar los tocoferoles naturales presentes en los aceites, fueron sometidas a termoxidación, a 180 °C durante 10 horas. Se tomaron muestras en los tiempos 0, 2, 5, 8 y 10 horas, para determinación de dímeros y polímeros (compuestos de degradación y de tocoferoles. Se verificó la relación del índice de yodo con la formación de dímeros y polímeros, y también el papel de los tocoferoles originales del aceite y de las grasas en la protección contra la degradación térmica. Las curvas de degradación de los tocoferoles mostraron la destrucción más rápida de α y γ -tocoferoles, respecto a β y δ-tocoferoles. Además, la degradación de los tocoferoles ocurrió a mayor velocidad en las grasas más saturadas. La formación de dímeros y polímeros fue mayor en el aceite que en las muestras hidrogenadas y en las muestras tratadas

  13. Improved thermal stability of methylsilicone resins by compositing with N-doped graphene oxide/Co3O4 nanoparticles

    International Nuclear Information System (INIS)

    Jiang, Bo; Zhao, Liwei; Guo, Jiang; Yan, Xingru; Ding, Daowei; Zhu, Changcheng; Huang, Yudong; Guo, Zhanhu

    2016-01-01

    Nanoparticles play important roles in enhancing the thermal-resistance of hosting polymer resins. Despite tremendous efforts, developing thermally stable methylsilicone resin at high temperatures is still a challenge. Herein, we report a strategy to increase the activation energy to slow down the decomposition/degradation of methylsilicone resin using synergistic effects between the Co 3 O 4 nanoparticles and the nitrogen doped graphene oxide. The N-doped graphene oxides composited with Co 3 O 4 nanoparticles were prepared by hydrolysis of cobalt nitrate hexahydrate in the presence of graphene oxide and were incorporated into the methylsilicone resin. Two-stage decompositions were observed, i.e., 200–300 and 400–500 °C. The activation energy for the low temperature region was enhanced by 47.117 kJ/mol (vs. 57.76 kJ/mol for pure resin). The enhanced thermal stability was due to the fact that the nanofillers prevented the silicone hydroxyl chain ends ‘‘biting’’ to delay the degradation. The activation energy for high-temperature region was enhanced by 11.585 kJ/mol (vs. 171.95 kJ/mol for pure resin). The nanofillers formed a protective layer to isolate oxygen from the hosting resin. The mechanism for the enhanced thermal stability through prohibited degradation with synergism of these nitrogen-doped graphene oxide nanocomposites was proposed as well.Graphical Abstract

  14. Developing a Thermal- and Coking-Resistant Cobalt-Tungsten Bimetallic Anode Catalyst for Solid Oxide Fuel Cells

    NARCIS (Netherlands)

    Yan, N.; Pandey, J.; Zeng, Y.; Amirkhiz, B.S.; Hua, B.; Geels, N.J.; Luo, J.L.; Rothenberg, G.

    2016-01-01

    We report the development of a novel Co–W bimetallic anode catalyst for solid oxide fuel cells (SOFCs) via a facile infiltration-annealing process. Using various microscopic and spectroscopic measurements, we find that the formed intermetallic nanoparticles are highly thermally stable up to 900 °C

  15. Shape-stabilized phase change materials with high thermal conductivity based on paraffin/graphene oxide composite

    International Nuclear Information System (INIS)

    Mehrali, Mohammad; Latibari, Sara Tahan; Mehrali, Mehdi; Metselaar, Hendrik Simon Cornelis; Silakhori, Mahyar

    2013-01-01

    Highlights: ► The composite PCM was prepared with impregnation method. ► Shapes stabilized phase change material made with paraffin and GO composite. ► Determine effects of GO composite on shape stabilized PCM properties. ► The composite PCM has good thermal stability and form-stability. ► The composite PCM has much higher thermal conductivity than that of paraffin. - Abstract: This paper mainly focuses on the preparation, characterization, thermal properties and thermal stability and reliability of new form-stable composite phase change materials (PCMs) prepared by vacuum impregnation of paraffin within graphene oxide (GO) sheets. SEM and FT-IR techniques and TGA and DSC analysis are used for characterization of material and thermal properties. The composite PCM contained 48.3 wt.% of paraffin without leakage of melted PCM and therefore this composite found to be a form-stable composite PCM. SEM results indicate that the paraffin bounded into the pores of GO. FT-IR analysis showed there was no chemical reaction between paraffin and GO. Temperatures of melting and freezing and latent heats of the composite were 53.57 and 44.59 °C and 63.76 and 64.89 kJ/kg, respectively. Thermal cycling tests were done by 2500 melting/freezing cycling for verification of the form-stable composite PCM in terms of thermal reliability and chemical stability. Thermal conductivity of the composite PCM was highly improved from 0.305 to 0.985 (W/mk). As a result, the prepared paraffin/GO composite is appropriate PCM for thermal energy storage applications because of their acceptable thermal properties, good thermal reliability, chemical stability and thermal conductivities

  16. Influence of thermal oxidation duration on the microstructure and fretting wear behavior of Ti6Al4V alloy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Song [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Liao, Zhenhua [Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China); Liu, Yuhong [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Liu, Weiqiang, E-mail: weiqliu@hotmail.com [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Biomechanics and Biotechnology Lab, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China)

    2015-06-01

    Thermal oxidation under water oxidizing atmosphere was performed on Ti6Al4V alloy under different durations from 2 h to 8 h. Surface characterizations were performed using X-ray diffractometery (XRD), scanning electron microscopy (SEM), Raman spectroscopy, nanoindentation and nano scratch testing. Fretting wear behaviors of untreated and oxidized samples were also examined. The formed oxide coating mainly included rutile TiO{sub 2} as well as a little alumina. The weight gain with respect to the oxidation duration obeyed the linear oxidation kinetics law. The growth of oxide grains was in inadequate growth state of incomplete scale coverage from 2nd to 4th hour duration, in normal growth state from 4th to 6th hour duration while in excessive growth state of oxide particle agglomeration and surface roughening from 6th to 8th (or more than 8th) hour duration. The coating thickness increased from 5 μm to 12 μm as oxidation duration increased from 2 h to 8 h. The increase in duration also increased surface roughness and nano hardness as well as adhesion strength of the film/substrate for oxidized samples. The nano hardness value was 10.06 ± 2.15 GPa and the critical load of failure during nano scratch testing was 554.3 ± 6.44 mN for 4 h treated sample. The untreated and oxidized samples showed a same fretting running status and fretting regime with a displacement amplitude of 200 μm while revealing different fretting failure mechanisms. It was mainly abrasive and adhesive wear under ploughing force for untreated sample, while a mix of 3-body abrasion by rolling oxide particles and severe plastic deformation under high contact stress between two ceramic materials for the oxidized samples. The oxide coating was not worn out and improved the fretting wear resistance of titanium alloy. - Highlights: • A thickness of 5–12 μm rutile TiO{sub 2} coating formed under different oxidation durations. • Weight gain with respect to oxidation duration obeyed linear

  17. The influence of Al(OH)3-coated graphene oxide on improved thermal conductivity and maintained electrical resistivity of Al2O3/epoxy composites

    International Nuclear Information System (INIS)

    Heo, Yuseon; Im, Hyungu; Kim, Jiwon; Kim, Jooheon

    2012-01-01

    This study investigates the thermal and electrical conductivity of Al 2 O 3 /epoxy composites containing graphene oxide and Al(OH) 3 -coated graphene oxide. The functionalized graphene oxide was prepared by sol–gel method with aluminum isopropoxide (AlIP). The aluminum hydroxide layer (50–150 nm) was successfully formed on graphene oxide surface. The introduction of both graphene oxide and Al(OH) 3 -coated graphene oxide in Al 2 O 3 /epoxy composites significantly improved the thermal conductivity due to the high thermal conductivity of graphene-based materials and their role as heat conductive bridges among the Al 2 O 3 particles ( 2 O 3 /epoxy composites-containing 5 wt% graphene oxide and Al(OH) 3 -coated graphene oxide are 3.5 and 3.1 W/mK, respectively. On the other hand, the Al(OH) 3 -coated graphene oxide/Al 2 O 3 /epoxy composites exhibited the more retained electrical resistivity compared with graphene oxide/Al 2 O 3 /epoxy composite. Thus, the Al(OH) 3 -coated graphene oxide composites showed simultaneously improvements in the thermal conductivity and retention of electrical resistivity.

  18. Thermal decomposition of ethylene oxide on Pd(111). Comparison of the pathways for the selective oxidation of ethylene and olefin metathesis

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, R.M. (Univ. of Cambridge (United Kingdom)); Ormerod, R.M. (Univ. of Keele (United Kingdom)); Tysoe, W.T. (Univ. of Wisconsin, Milwaukee, WI (United States))

    1994-03-01

    The product distribution detected in the multimass temperature-programmed desorption of a saturated overlayer of ethylene oxide adsorbed on Pd(111) at [approximately] 180 K indicates that it decomposes to yield ethylene and acetaldehyde. These observations are interpreted by postulating that ethylene oxide reacts to form an oxymetallocycle. This is proposed to thermally decompose in a manner analogous to carbometallocycles that form during olefin metathesis catalysis by the reaction between an alkene and a surface carbene. Thus, the metallocycle can decompose to yield ethylene and deposit adsorbed atomic oxygen or undergo a [beta]-hydrogen transfer to form acetaldehyde. 25 refs., 2 figs., 1 tab.

  19. Effects of inclusion level on nutrient digestibility and energy content of wheat middlings and soya bean meal for growing pigs.

    Science.gov (United States)

    Huang, Qiang; Piao, Xiangshu; Liu, Ling; Li, Defa

    2013-01-01

    Two experiments were conducted to determine the effects of inclusion level of wheat middlings and soya bean meal on apparent total tract digestibility (ATTD) of energy and chemical components of these ingredients in growing pigs. Furthermore, the effects of the inclusion level on their contents of digestible energy (DE) and metabolisable energy (ME) were also determined by the difference method. In Experiment 1, six diets were fed to 36 growing pigs according to a completely randomised design. The basal diet was a corn-soya bean meal diet while the other five diets contained 9.6%, 19.2%, 28.8%, 38.4% or 48.0% of wheat middlings added at the expense of corn and soya bean meal. The measured digestibility of energy and most nutrients of wheat middlings increased (p soya bean meal (22.2% and 33.6%). The content of DE in soya bean meal did not differ at 22.2% and 33.6% inclusion levels (16.2 and 16.3 MJ/kg DM, respectively), but the digestibility of dry matter (DM), organic matter and carbohydrates was increased at a higher inclusion level (p soya bean meal and wheat middlings was affected by their dietary inclusion levels. For soya bean meal, the estimated energy contents was independent of its inclusion level, but not for wheat middlings. Therefore, the inclusion level of wheat middlings has to be considered for estimating their energy value.

  20. Relative efficacy of casein or soya protein combined with palm or safflower-seed oil on hyperuricaemia in rats.

    Science.gov (United States)

    Lo, Hui-Chen; Wang, Yao-Horng; Chiou, Hue-Ying; Lai, Shan-Hu; Yang, Yu

    2010-07-01

    Diets that ameliorate the adverse effects of uric acid (UA) on renal damage deserve attention. The effects of casein or soya protein combined with palm or safflower-seed oil on various serum parameters and renal histology were investigated on hyperuricaemic rats. Male Wistar rats administered with oxonic acid and UA to induce hyperuricaemia were fed with casein or soya protein plus palm- or safflower-seed oil-supplemented diets. Normal rats and hyperuricaemic rats with or without allopurinol treatment (150 mg/l in drinking water) were fed with casein plus maize oil-supplemented diets. After 8 weeks, allopurinol treatment and soya protein plus safflower-seed oil-supplemented diet significantly decreased serum UA in hyperuricaemic rats (one-way ANOVA; P soya protein and casein attenuated hyperuricaemia-induced decreases in serum albumin and insulin, respectively (two-way ANOVA; P soya protein significantly decreased renal NO and nitrotyrosine and palm oil significantly decreased renal nitrotyrosine, TNF-alpha and interferon-gamma and increased renal transforming growth factor-beta. Casein with safflower-seed oil significantly attenuated renal tubulointerstitial nephritis, crystals and fibrosis. Comparing casein v. soya protein combined with palm or safflower-seed oil, the results support that casein with safflower-seed oil may be effective in attenuating hyperuricaemia-associated renal damage, while soya protein with safflower-seed oil may be beneficial in lowering serum UA and TAG.

  1. Experimentally Studied Thermal Piston-head State of the Internal-Combustion Engine with a Thermal Layer Formed by Micro-Arc Oxidation Method

    Directory of Open Access Journals (Sweden)

    N. Yu. Dudareva

    2015-01-01

    Full Text Available The paper presents results of experimental study to show the efficiency of reducing thermal tension of internal combustion engine (ICE pistons through forming a thermal barrier coating on the piston-head. During the engine operation the piston is under the most thermal stress. High temperatures in the combustion chamber may lead to the piston-head burnout and destruction and engine failure.Micro-arc oxidation (MAO method was selected as the technology to create a thermal barrier coating. MAO technology allows us to form the ceramic coating with a thickness of 400μm on the surface of aluminum alloy, which have high heat resistance, and have good adhesion to the substrate even under thermal cycling stresses.Deliverables of MAO method used to protect pistons described in the scientific literature are insufficient, as they are either calculated or experimentally obtained at the special plants (units, which do not reproduce piston operation in a real engine. This work aims to fill this gap. The aim of the work is an experimental study of the thermal protective ability of MAO-layer formed on the piston-head with simulation of thermal processes of the real engine.The tests were performed on a specially designed and manufactured stand free of motor, which reproduces operation conditions maximum close to those of the real engine. The piston is heated by a fire source - gas burner with isobutene balloon, cooling is carried out by the water circulation system through the water-cooling jacket.Tests have been conducted to compare the thermal state of the regular engine piston without thermal protection and the piston with a heat layer formed on the piston-head by MAO method. The study findings show that the thermal protective MAO-layer with thickness of 100μm allows us to reduce thermal tension of piston on average by 8,5 %. Thus at high temperatures there is the most pronounced effect that is important for the uprated engines.The obtained findings can

  2. Underwater Superoleophobicity Induced by the Thickness of the Thermally Grown Porous Oxide Layer on C84400 Copper Alloy

    Directory of Open Access Journals (Sweden)

    Aniedi Nyong

    2014-02-01

    Full Text Available The underwater contact angle behavior on oxide layers of varying thicknesses was studied. These oxide layers were grown by thermally oxidizing C84400 copper alloys in N2-0.75 wt.% O2 and N2-5 wt.% O2 gas mixtures at 650 °C. Characterization of the oxidized specimens was effected using X-ray diffraction, scanning electron microscope (SEM and contact angle goniometer. The results from the X-ray diffraction analyses confirmed the formation of CuO, ZnO and PbO. The average sizes of the oxide granules were in the range of 70 nm to 750 nm, with the average thickness of the oxide layer increasing with the increase in the weight percent of oxygen in the N2-O2 gas mixtures. The results showed that the oxide layer growth followed the parabolic law. The underwater oil contact angles increased, due to the change in the surface morphology and porosity of the oxide layer. The small sizes and irregular packing of the oxide granules cause hierarchical rough surface layers with pores. The estimated pore sizes, in the range of 88 ± 40 to 280 ± 76, were predominant on the oxide layers of the samples processed in the N2-5 wt.% O2 gas mixture. The presence of these pores caused an increase in the porosities as the thickness of the oxide layers increased. At oxide layer thickness above 25 microns, the measured contact angle exceeded 150° as underwater superoleophobicity was recorded.

  3. Real-time monitoring of initial thermal oxidation on Si(001) surfaces by synchrotron radiation photoemission spectroscopy

    CERN Document Server

    Yoshigoe, A; Teraoka, Y

    2003-01-01

    The thermal oxidation of Si(001) surfaces at 860 K, 895 K, 945 K and 1000 K under the O sub 2 pressure of 1 x 10 sup - sup 4 Pa has been investigated by time-resolved photoemission measurements with synchrotron radiation. Based on time evolution analyses by reaction kinetics models, it was found that the oxidation at 860 K, 895 K and 945 K has progressed with the Langmuir adsorption type, whereas the oxidation at 1000 K has showed the character of the two-dimensional island growth involving SiO desorption. The oxidation rates increases with increasing surface temperature in the passive oxidation condition. The time evolution of each Si oxidation state (Si sup n sup + : n = 1, 2, 3, 4) derived from the Si-2p core-level shifts has also been analyzed. The results revealed that the thermal energy contribution to the migration process of the adsorbed oxygen and the emission of the bulk silicon atoms. Thus, the fraction of the Si sup 4 sup + bonding state, i.e. SiO sub 2 structure, was increased. (author)

  4. Nanocomposites of cellulose/iron oxide: influence of synthesis conditions on their morphological behavior and thermal stability

    International Nuclear Information System (INIS)

    Ma Mingguo; Zhu Jiefang; Li Shuming; Jia Ning; Sun Runcang

    2012-01-01

    Nanocomposites of cellulose/iron oxide have been successfully prepared by hydrothermal method using cellulose solution and Fe(NO 3 ) 3 ·9H 2 O at 180 °C. The cellulose solution was obtained by the dissolution of microcrystalline cellulose in NaOH/urea aqueous solution, which is a good system to dissolve cellulose and favors the synthesis of iron oxide without needing any template or other reagents. The phases, microstructure, and morphologies of nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectra (EDS). The effects of the heating time, heating temperature, cellulose concentration, and ferric nitrate concentration on the morphological behavior of products were investigated. The experimental results indicated that the cellulose concentration played an important role in both the phase and shape of iron oxide in nanocomposites. Moreover, the nanocomposites synthesized by using different cellulose concentrations displayed different thermal stabilities. - Highlights: ► Nanocomposites of cellulose/iron oxide have been prepared by hydrothermal method. ► The cellulose concentration played an important role in the phase of iron oxide. ► The cellulose concentration played an important role in the shape of iron oxide. ► The samples displayed different thermal stabilities.

  5. Composite plasma electrolytic oxidation to improve the thermal radiation performance and corrosion resistance on an Al substrate

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Donghyun [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of); Sung, Dahye [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of); Korea Institute of Industrial Technology (KITECH), Busan 46742 (Korea, Republic of); Lee, Junghoon [Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Kim, Yonghwan [Korea Institute of Industrial Technology (KITECH), Busan 46742 (Korea, Republic of); Chung, Wonsub, E-mail: wschung1@pusan.ac.kr [Department of Materials Science and Engineering, Pusan National University, Busan 46241 (Korea, Republic of)

    2015-12-01

    Highlights: • Composite plasma electrolytic oxidation was performed using dispersed CuO particles in convectional PEO electrolyte. • Thermal radiation performance and corrosion resistance were examined by FT-IR spectroscopy and electrochemical methods, respectively. • Deposited copper oxide on the surface of the Al substrate was enhanced the corrosion resistance and the emissivity compared with the conventional PEO. - Abstract: A composite plasma electrolytic oxidation (PEO) was performed for enhancing the thermal radiation performance and corrosion resistance on an Al alloy by dispersing cupric oxide (CuO) particles in a conventional PEO electrolyte. Cu-based oxides (CuO and Cu{sub 2}O) formed by composite PEO increased the emissivity of the substrate to 0.892, and made the surface being dark color, similar to a black body, i.e., an ideal radiator. In addition, the corrosion resistance was analyzed using potentio-dynamic polarization and electrochemical impedance spectroscopy tests in 3.5 wt.% NaCl aqueous solution. An optimum condition of 10 ampere per square decimeter (ASD) current density and 30 min processing time produced appropriate surface morphologies and coating thicknesses, as well as dense Cu- and Al-based oxides that constituted the coating layers.

  6. Growth of ZnO nanowires through thermal oxidation of metallic zinc films on CdTe substrates

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, O., E-mail: oscar@fmc.uva.es [Optronlab Group, Dpto. Fisica Materia Condensada, Edificio I-D, Universidad de Valladolid, Paseo de Belen 1, 47011, Valladolid (Spain); Hortelano, V.; Jimenez, J. [Optronlab Group, Dpto. Fisica Materia Condensada, Edificio I-D, Universidad de Valladolid, Paseo de Belen 1, 47011, Valladolid (Spain); Plaza, J.L.; Dios, S. de; Olvera, J.; Dieguez, E. [Laboratorio de Crecimiento de Cristales, Departamento de Fisica de Materiales, Facultad de Ciencias, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Fath, R.; Lozano, J.G.; Ben, T.; Gonzalez, D. [Dpto. Ciencia de los Materiales e Ingenieria Metalurgica y Q.I., Facultad de Ciencias, Apdo. 40, 11510 Puerto Real, Cadiz (Spain); Mass, J. [Dpto. de Fisica, Universidad del Norte, Km.5 Via Puerto Colombia, Barranquilla (Colombia)

    2011-04-28

    Research highlights: > ZnO nanowires grown from thermal Zn oxidation. > TEM reveals high quality thin nanowires several microns long. > New phase formation at long oxidation time. > Good spectroscopic properties measured by Raman, Photo and Cathodoluminsecence spectroscopies. - Abstract: <112-bar 0> wurtzite ZnO nanowires (NWs) have been obtained by oxidizing in air at 500 deg. C thermally evaporated Zn metal films deposited onto CdTe substrates. The presence of Cd atoms from the substrate on the ZnO seeding layer and NWs seems to affect the growth of the NWs. The effects of the oxidation time on the structural and optical properties of the NWs are described in detail. It is shown that the NWs density decreases and their length increases when increasing the oxidation time. Thicker Zn layers result in thinner and longer ZnO NWs. Very long oxidation times also lead to the formation of a new CdO phase which is related to the partial destruction and quality reduction of the NWs. The possible process for ZnO NW formation on CdTe substrates is discussed.

  7. Liquid products from oxidative thermal treatment of oil sludge with different oxygen concentrations of air.

    Science.gov (United States)

    Shie, J L; Chang, C Y; Lin, J P; Le, D J; Wu, C H

    2001-01-01

    Oxidative thermal treatment of oil sludge with different oxygen concentrations of air by using a dynamic thermogravimetric (TG) reaction system is investigated. The experimental conditions employed are: gas flow rate of 50 cm3/min (value at 298 K) for 300 mg dry waste, a constant heating rate of 5.2 K/min, the oxygen concentrations in air of 1.09, 8.62 and 20.95 vol. % O2, and the temperature (T) range of 378-873 K. From the experimental results, the residual mass fractions (M) are about 78.95, 28.49, 8.77 and 4.13 wt. % at the oxidative T of 563, 713, 763 and 873 K for the case with 20.95 vol. % O2, respectively. The values of M with 8.62 and 1.09 vol. % O2 at T of 873 K are 4.87 and 9.44 wt. %, respectively. The distillation characteristics of the oil portion of liquid products (condensates of gas at 298 K) from the oxidative thermal treatment of oil sludge with 20.95 vol. % O2 at T of 378-873 K is close to those of commercial gasoline. Nevertheless, the liquid product contains a large amount of water. The distillation characteristics of the oil portions of liquid products with 8.62 and 1.09 vol. % O2 at T of 378-873 K are close to those of diesel and fuel oils, respectively. The oil quality with 8.62 vol. % O2 is better than that with 1.09 vol. % O2. However, the liquid product with 8.62 vol. % O2 still contains a large amount of water; nonetheless, that with 1.09 vol. % O2 is with negligible water. Compared with the oil product of nitrogen pyrolysis, the oil quality with 1.09 vol. % O2 is better. Certainly, low oxygen conditions (i.e. 1.09 vol. % O2) not only accelerate the thermal reaction of oil sludge, but also at the same time avoid or reduce the production of water. Further, from the analysis of benzene (B), ethylbenzene (E), toluene (T) and iso-xylene (X) concentrations of the oil portion of liquid products, the BETX concentrations of oil with 20.95 vol. % O2 are higher than those with 8.62 and 1.09 vol. % O2. The yields of liquid products with 20.95, 8

  8. Effects of Combined Selective Aerobic Moderate Intensity Exercises and Soya Intake on Serum Lipids and Obesity in Obese Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    A Zarneshan

    2012-02-01

    Full Text Available Background & Aim: Today, the percentage of deaths due to heart diseases has increased and along with the exercise training role in reducing obesity and cardiovascular disease, soy is a useful source of food in reducing blood lipid and obesity. The present study investigated the effect of combined selective short aerobic moderate intensity exercise and soya intake on serum lipids and obesity in obese postmenopausal women. Methods: In the present quasi-experimental study conducted in 2006 on women of Urmia, Iran, 56 obese postmenopausal women were selected and randomly divided into four groups of 14 subjects as follow: exercise-soya, exercise, soya, and control group. Pre- and post protocol blood samples were collected and the level of TG (Triglyceride, tCho (Total Cholesterol, LDL-C (Low density lipoprotein, HDL-C (high density lipoprotein were measured. Exercise training within the range of 60-70% maximum heart rate (MHR was performed for 60 minutes, 3 sessions per week. The subjects of soya group and exercise-soya group had a 100 gram soya nut intake daily for 10 weeks. After The training course, blood samples were taken from the subjects. The collected data was analyzed using Two-way ANOVA and paired t-test. Results: Having soya along with exercise had significant impact on reduction of TG, tCho, LDL-C means (p<0.05. Body mass index and waist to hip ratio decreased significantly in exercise-soya group after 10 weeks (p<0.05. Conclusion: Based on the findings of this study, aerobic moderate intensity exercise along with soya intake, decrease obesity and serum lipids in obese postmenopausal women.

  9. Natural occurrence of alternariol and alternariol monomethyl ether in soya beans.

    Science.gov (United States)

    Oviedo, M S; Barros, G G; Chulze, S N; Ramirez, M L

    2012-08-01

    The natural occurrence of alternariol (AOH) and alternariol monomethyl ether (AME) in soya beans harvested in Argentina was evaluated. Both toxins were simultaneously detected by using HPLC analysis coupled with a solid phase extraction column clean-up. Characteristics of this in-house method such as accuracy, precision and detection and quantification limits were defined by means of recovery test with spiked soya bean samples. Out of 50 soya bean samples, 60% showed contamination with the mycotoxins analyzed; among them, 16% were only contaminated with AOH and 14% just with AME. Fifteen of the positive samples showed co-occurrence of both mycotoxins analyzed. AOH was detected in concentrations ranging from 25 to 211 ng/g, whereas AME was found in concentrations ranging from 62 to 1,153 ng/g. Although a limited number of samples were evaluated, this is the first report on the natural occurrence of Alternaria toxins in soya beans and is relevant from the point of view of animal public health.

  10. Effect of ultra high pressure homogenization treatment on the bioactive compounds of soya milk.

    Science.gov (United States)

    Toro-Funes, N; Bosch-Fusté, J; Veciana-Nogués, M T; Vidal-Carou, M C

    2014-01-01

    Ultra high pressure homogenization (UHPH) is a useful novel technology to obtain safe and high-quality liquid foods. The effect of UHPH at 200 and 300 MPa in combination with different inlet temperatures (Tin) (55, 65 and 75 °C) on the bioactive compounds of soya milk was studied. Total phytosterols increased with the higher combination of pressure and temperature. The main phytosterol was β-sitosterol, followed by stigmasterol and campesterol. Total tocopherols in UHPH-treated soya milks decreased as the temperature and pressure increased. UHPH treatment also affected the different chemical forms of tocopherols. No biogenic amines were detected in any of the analyzed soya milks. Meanwhile, the polyamines SPD and SPM were found in all soya milks, being stable to the UHPH treatment. Total isoflavones increased with the higher combination of pressure and temperature. No differences in the isoflavone profile were found, with β-glucoside conjugates being the predominant form. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Biogas production enhancement by soya sludge amendment in cattle dung digesters

    Energy Technology Data Exchange (ETDEWEB)

    Satyanarayan, Shanta; Ramakant; Shivayogi [WWT Division, NEERI, Nagpur 400 020 (India)

    2010-09-15

    Biogas energy production from cattle dung is an economically feasible and eco-friendly in nature. But dependence only on cattle dung is a limiting factor. Rich nitrogen containing substrate addition to extra carbohydrate digester like cattle dung could improve the biogas production. Detailed performance of the digesters at different ratios of cattle dung and soya sludge has been discussed in this paper considering the cold countries climate. Soya sludge substrate not only has high nitrogen content of 4.0-4.8% but it also has high percentage of volatile solids content in the range of 97.8-98.8%. Soya sludge addition also improved the manurial value of the digested slurry and also improved the dewater-ability of the sludge. Results indicated an increment of 27.0% gas production at 25.0% amendment of soya sludge in non-homogenized cattle dung (NCD) digester. The amount of gas production increased to 46.4% in case of homogenized cattle dung (HCD) with respect to NCD feed at the same amendment. (author)

  12. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.; Nout, M.J.R.; Beumer, R.R.; Meulen, van der J.; Zwietering, M.H.

    2009-01-01

    Aims: This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and

  13. Prenylated isoflavonoids from soya and licorice : analysis, induction and in vitro estrogenicity

    NARCIS (Netherlands)

    Simons, R.

    2011-01-01


    Prenylatedisoflavonoids are found in large amountsin soya bean (Glycine max) germinated under stress and in licorice (Glycyrrhiza glabra). Prenylation of isoflavonoids has been associated with modification of theirestrogenic activity.
    The aims of this thesis were (1) to provide a

  14. Influence of Wet Soya Waste on Nutrient Utilization by Red Sokoto ...

    African Journals Online (AJOL)

    Trial was conducted to determine the influence of wet soya waste (WSW) on nutrient utilization in Red Sokoto goats fed Digitaria smutsii hay basal diet. Four mature bucks of 11.32kg body weight were allotted to four dietary treatments which were 0, 200, 400 and 600g levels of WSW in 4 X 4 Latin square design. There was ...

  15. The Effect of Soya bean ( Glycine max ) on Pefloxacin Absorption in ...

    African Journals Online (AJOL)

    The study was to investigate the effect of soya bean on the absorption of pefloxacin when given by oral route in rats. The first group of animals feeding on standard pellet feeds was given pefloxacin (8 mg/kg, p.o), while the second and third groups were also given the drug at the same dosage level but were fed with 50 ...

  16. Bioactive components of fermented soya beans effective against diarrhoea-associated bacteria

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.

    2010-01-01

    Tempe is a fermented food, obtained by fungal fermentation of soya beans. During the processing specific flavour, texture and nutritional properties are achieved. Previous research has indicated that tempe reduced the incidence and severity of diarrhoea. In this thesis the bioactive effects of tempe

  17. KAJIAN PENGARUH KADAR GULA DAN LAMA FERMENTASI TERHADAP KUALITAS NATA de SOYA

    Directory of Open Access Journals (Sweden)

    Siti Nurhayati

    2016-09-01

    Full Text Available The aim of the research was to determine the effect of sugar content, time length of fermentations and their interaction on the qualities of the Nata de Soya. The design of the experiment was factorial 3x2 and arranged by the Randomized Complete Design (RCD, with three replications. The first factor was sugar content. G1= 100 g sucrose/l waste of soya, G2= 150 g/l and G3= 200 g/l. The second factor was days of the fermentation F1= 7 days, F2= 14 days. The result showed that (i the adding of sugar content was not affected the weight, temperature, acidity, moisture content, fiber content and protein content of the Nata de Soya. (ii The days of fermentation were significant in affecting the weight of the Nata de Soya, but not significant for other parameters. The maximum weight (418,411g was reached at 7 days of the fermentations. (iii The interaction between sugar content and time length of fermentations influenced acidity.

  18. Production of peptone from soya beans (Glycine max L merr) and ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-09-18

    Sep 18, 2006 ... Peptone was produced from soya beans and African locust beans. The produced peptones were evaluated as component of microbiological media for the growth of some bacteria and compared with some commercial peptones. Some of the tested bacteria are Escherichia coli, Pseudomonas aeruginosa ...

  19. Comparison of two soya bean simulation models under climate change : II Application of climate change scenarios

    NARCIS (Netherlands)

    Wolf, J.

    2002-01-01

    The effects of climate change (for 2050 compared to ambient climate) and change in climatic variability on soya bean growth and production at 3 sites in the EU have been calculated. These calculations have been done with both a simple growth model, SOYBEANW, and a comprehensive model, CROPGRO.

  20. “Eat dry beans, split peas, lentils and soya regularly”: A food-based ...

    African Journals Online (AJOL)

    Eat dry beans, split peas, lentils and soya regularly”: A food-based dietary guideline. ... Legumes are rich and economical sources of good-quality protein, slow-release carbohydrates, dietary fibre (non-starch polysaccharides), various vitamins and minerals and non-nutritive components which may have several beneficial ...

  1. Soya bean tempe extracts show antibacterial activity against Bacillus cereus cells and spores

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.; Dalmas, E.; Nout, M.J.R.; Abee, T.

    2010-01-01

    Aims: Tempe, a Rhizopus ssp.-fermented soya bean food product, was investigated for bacteriostatic and/or bactericidal effects against cells and spores of the food-borne pathogen Bacillus cereus. Methods and results: Tempe extract showed a high antibacterial activity against B. cereus ATCC 14579

  2. Solid-substrate fermentation of soya beans to tempe : process innovations and product characteristics

    NARCIS (Netherlands)

    Reu, de J.C.

    1995-01-01

    Solid-substrate fermentations (SSF) are restricted by heat- and mass transfer limitations, which might result in unfavourable growth conditions. One way to prevent such conditions is by agitation of the substrate. In this study a Rotating Drum Reactor (RDR) was designed for the fermentation of soya

  3. Fermentation characteristics of polysaccharide fractions extracted from the cell walls of soya bean cotyledons

    NARCIS (Netherlands)

    Laar, van H.; Tamminga, S.; Williams, B.A.; Verstegen, M.W.A.; Schols, H.A.

    2000-01-01

    Full-fat soya beans were separated into hulls and cotyledons. After separation the cell wall fraction was extracted from the cotyledons. These purified cell walls were sequentially extracted with 0.05 M cyclohexane-trans-1,2-diamine-N,N,N ,N -tetraacetate (CDTA) 0.05 M NH4 oxalate (extract 1), 0.05

  4. Synthesis of metal-fluoride nanoparticles supported on thermally reduced graphite oxide

    Directory of Open Access Journals (Sweden)

    Alexa Schmitz

    2017-11-01

    Full Text Available Metal-fluoride nanoparticles, (MFx-NPs with M = Fe, Co, Pr, Eu, supported on different types of thermally reduced graphite oxide (TRGO were obtained by microwave-assisted thermal decomposition of transition-metal amidinates, (M{MeC[N(iPr]2}n or [M(AMDn] with M = Fe(II, Co(II, Pr(III, and tris(2,2,6,6-tetramethyl-3,5-heptanedionatoeuropium, Eu(dpm3, in the presence of TRGO in the ionic liquid (IL 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF4]. The crystalline phases of the metal fluorides synthesized in [BMIm][BF4] were identified by powder X-ray diffraction (PXRD to be MF2 for M = Fe, Co and MF3 for M = Eu, Pr. The diameters and size distributions of MFx@TRGO were from (6 ± 2 to (102 ± 41 nm. Energy-dispersive X-ray spectroscopy (EDX and X-ray photoelectron spectroscopy (XPS were used for further characterization of the MFx-NPs. Electrochemical investigations of the FeF2-NPs@TRGO as cathode material for lithium-ion batteries were evaluated by galvanostatic charge/discharge profiles. The results indicate that the FeF2-NPs@TRGO as cathode material can present a specific capacity of 500 mAh/g at a current density of 50 mA/g, including a significant interfacial charge storage contribution. The obtained nanomaterials show a good rate capacity as well (220 mAh/g and 130 mAh/g at a current density of 200 and 500 mA/g, respectively.

  5. Thermal stress management of a solid oxide fuel cell using neural network predictive control

    International Nuclear Information System (INIS)

    Hajimolana, S.A.; Tonekabonimoghadam, S.M.; Hussain, M.A.; Chakrabarti, M.H.; Jayakumar, N.S.; Hashim, M.A.

    2013-01-01

    In SOFC (solid oxide fuel cell) systems operating at high temperatures, temperature fluctuation induces a thermal stress in the electrodes and electrolyte ceramics; therefore, the cell temperature distribution is recommended to be kept as constant as possible. In the present work, a mathematical model based on first principles is presented to avert such temperature fluctuations. The fuel cell running on ammonia is divided into five subsystems and factors such as mass/energy/momentum transfer, diffusion through porous media, electrochemical reactions, and polarization losses inside the subsystems are presented. Dynamic cell-tube temperature responses of the cell to step changes in conditions of the feed streams is investigated. The results of simulation indicate that the transient response of the SOFC is mainly influenced by the temperature dynamics. It is also shown that the inlet stream temperatures are associated with the highest long term start-up time (467 s) among other parameters in terms of step changes. In contrast the step change in fuel velocity has the lowest influence on the start-up time (about 190 s from initial steady state to the new steady state) among other parameters. A NNPC (neural network predictive controller) is then implemented for thermal stress management by controlling the cell tube temperature to avoid performance degradation by manipulating the temperature of the inlet air stream. The regulatory performance of the NNPC is compared with a PI (proportional–integral) controller. The performance of the control system confirms that NNPC is a non-linear-model-based strategy which can assure less oscillating control responses with shorter settling times in comparison to the PI controller. - Highlights: • Effect of the operating parameters on the fuel cell temperature is analysed. • A neural network predictive controller (NNPC) is implemented. • The performance of NNPC is compared with the PI controller. • A detailed model is used for

  6. Synthesis and structural, magnetic, thermal, and transport properties of several transition metal oxides and aresnides

    Energy Technology Data Exchange (ETDEWEB)

    Das, Supriyo [Iowa State Univ., Ames, IA (United States)

    2010-01-01

    Oxide compounds containing the transition metal vanadium (V) have attracted a lot of attention in the field of condensed matter physics owing to their exhibition of interesting properties including metal-insulator transitons, structural transitions, ferromagnetic and an- tiferromagnetic orderings, and heavy fermion behavior. Binary vanadium oxides VnO2n-1 where 2 ≤ n ≤ 9 have triclinic structures and exhibit metal-insulator and antiferromagnetic transitions.[1–6] The only exception is V7O13 which remains metallic down to 4 K.[7] The ternary vanadium oxide LiV2O4 has the normal spinel structure, is metallic, does not un- dergo magnetic ordering and exhibits heavy fermion behavior below 10 K.[8] CaV2O4 has an orthorhombic structure[9, 10] with the vanadium spins forming zigzag chains and has been suggested to be a model system to study the gapless chiral phase.[11, 12] These provide great motivation for further investigation of some known vanadium compounds as well as to ex- plore new vanadium compounds in search of new physics. This thesis consists, in part, of experimental studies involving sample preparation and magnetic, transport, thermal, and x- ray measurements on some strongly correlated eletron systems containing the transition metal vanadium. The compounds studied are LiV2O4, YV4O8, and YbV4O8. The recent discovery of superconductivity in RFeAsO1-xFx (R = La, Ce, Pr, Gd, Tb, Dy, Sm, and Nd), and AFe2As2 (A = Ba, Sr, Ca, and Eu) doped with K, Na, or Cs at the A site with relatively high Tc has sparked tremendous activities in the condensed matter physics community and a renewed interest in the area of superconductivity as occurred following the discovery of the layered cuprate high Tc superconductors in 1986. To discover more supercon- ductors

  7. Efectos de la soya en la mucosa endometrial de mujeres posmenopáusicas

    Directory of Open Access Journals (Sweden)

    Delia Jara

    2006-06-01

    Full Text Available Objetivo: Describir los cambios en la morfología del endometrio y expresión de receptores a estrógenos, en mujeres posmenopáusicas que reciben soya vía oral. Diseño: Estudio descriptvo, observacional, de tipo longitudinal y prospectivo. Lugar: Instituto de Patología, Universidad Nacional Mayor de San Marcos. Pacientes: Veintidós mujeres posmenopáusicas tratadas con soya. Intervenciones: A mujeres posmenopáusicas, tratadas con 60 g de soya por día, durante 6 meses, se les realizó biopsia por aspiración del endometrio, antes y después del tratamiento, efectuando estudios histológico e inmunohistoquímico. Principales medidas de resultados: Modificaciones histológicas del endometrio y de expresión de receptores de estrógenos y progesterona. Resultados: El rango de edad de las pacientes estuvo entre 46 y 65 años, con promedio de 53 años. Hubo aparente mejoría en los síntomas climatéricos vasomotores. El endometrio antes del tratamiento con soya en 19 pacientes (86% era atrófico y en 3 de ellas (14%, inactivo. Luego del tratamiento con soya, 17 (77,3% persistieron como endometrio atrófico, 4 (18,2% mostraron endometrio inactivo y el endometrio de una paciente mostró cambios proliferativos. La expresión de receptores para estrógenos, antes del tratamiento con soya, en 19 pacientes (86% fue negativo; después del tratamiento 16 (76% permanecieron negativos. Conclusiones: Después del tratamiento con soya, en mujeres posmenopáusicas, durante 6 meses, se observó persistencia de endometrio atrófico y se mantuvo la expresión negativa para receptores hormonales de estrógenos.

  8. Thermal oxidation of cholesterol: Preliminary evaluation of 2-methyl-6-heptanone and 3-methylbutanal as volatile oxidation markers.

    Science.gov (United States)

    Cardenia, Vladimiro; Olivero, Giulia; Rodriguez-Estrada, Maria Teresa

    2015-07-01

    Cholesterol oxidation in food and model systems is usually monitored by evaluating cholesterol oxidation products, but the analysis is time-consuming and expensive. Therefore, the determination of volatile compounds deriving from cholesterol thermoxidation could be valuable to identify other possible oxidation markers. Cholesterol alone and in the presence of a triacylglycerol mixture (tripalmitin, tristearin, and triolein) were thermoxidized at 170°C for 15min. In both model systems, the total volatile compounds increased three times when oxidation time rose from 5 to 15min. The main classes of volatile compounds were aldehydes, ketones, alcohols and hydrocarbons, displaying a similar behavior in both systems. After 5min of oxidation, 2-methyl-6-heptanone was the main volatile compound, followed by 3-methylpentane, 2,3-dimethyl-1-pentene and 3-methylbutanal. To verify if 2-methyl-6-heptanone could be used as volatile marker of cholesterol oxidation, data were compared with the total cholesterol oxidation products content of each system. A significant correlation between total cholesterol oxidation products content and 2-methyl-6-heptanone amount was found when cholesterol was oxidized alone (r(2)=0.994) and in presence of triacylglycerols (r(2)=0.998). When egg yolk was thermoxidized at 80°C for 6h, 3-methylbutanal was the volatile compound that better explained the oxidative trend in this food system, showing a significant correlation with cholesterol oxidation rate (r=0.91). In conclusion, 2-methyl-6-heptanone and 3-methylbutanal could represent an easy and cheaper strategy for monitoring cholesterol oxidation in model systems and food samples, respectively; however, a deeper investigation on the amount and type of volatile compounds generated from cholesterol oxidation according to the food matrix, should be carried out. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. CARACTERÍSTICAS DE LAS BEBIDAS CON PROTEÍNA DE SOYA CHARACTERISTICS OF THE DRINKS WITH SOYBEAN PROTEIN

    OpenAIRE

    Luz Stella Vanegas Pérez; Diego Alonso Restrepo Molina; Jairo Humberto López Vargas

    2009-01-01

    Se describe la soya desde el punto de vista bromatológico, nutricional y funcional, igualmente se desarrollan los aspectos asociados a los beneficios para la salud que han obtenido diversos autores mediante estudios clínicos, identificando los componentes responsables de esta acción. Posteriormente se desarrollan las características de funcionalidad fisicoquímica de la proteína de soya y su incidencia en los atributos sensoriales de las bebidas con soya, incluyendo las deficiencias que ésta p...

  10. Utilización de proteina de soya y carragenina en salchichas tipo Huacho con bajo tenor graso

    OpenAIRE

    Salva Ruíz, Bettit Karim

    2008-01-01

    Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Tecnología de Alimentos El presente trabajo de investigación consistió en determinar la influencia de la sustitución de grasa por la adición de hidrocoloides (proteina texturizada de soya, carragenina, concentrado funcional de soya), pellejo de cerdo y combinaciones de estas en las características de la salchicha tipo Huacho. Se emplearon concentraciones de 20, 30, 40 y 50% de proteína texturizada de soya, para reduci...

  11. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Science.gov (United States)

    Pittman, Joseph R.; Kline, La’Kesha C.; Kenyon, William J.

    2015-01-01

    The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation) is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance). To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C), low pH (pH 2.8), and oxidative stress (15 mM H2O2). In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth. PMID:27682115

  12. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Directory of Open Access Journals (Sweden)

    Joseph R. Pittman

    2015-10-01

    Full Text Available The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance. To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C, low pH (pH 2.8, and oxidative stress (15 mM H2O2. In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth.

  13. Effect of air-oxidation on the thermal diffusivity of the nuclear grade 2-dimensional carbon fiber reinforced carbon/carbon composite

    International Nuclear Information System (INIS)

    Sogabe, Toshiaki; Ishihara, Masahiro; Baba, Shin-ichi; Tachibana, Yukio; Yamaji, Masatoshi; Iyoku, Tatsuo; Hoshiya, Taiji

    2003-01-01

    2D-C/C composite is one of the promising materials as a next-generation core material in gas-cooled reactors. Effect of air-oxidation on the thermal diffusivity of the 2D-C/C composite was investigated in this study. Tested composite consists of 6K plain-woven fabrics with PAN-based carbon fiber and graphite matrix. Final heat-treatment of around 3073 K was applied to the composite. The C/C composite specimens for measurement of thermal diffusivity were oxidized from 1 to 11% weight loss in air at 823 K. Oxidation loss of the composite preferentially occurred at matrix part near the fiber bundles, and then occurred at fiber bundles. This composite exhibited large anisotropy in thermal diffusivity, higher value for parallel to lamina direction and lower value for perpendicular, e.g. thermal diffusivity of 1.1 cm 2 /s for parallel to lamina and 0.2 cm 2 /s for perpendicular at room temperature. Thermal diffusivity at room temperature declined 10∼20% for parallel to lamina direction and 5∼9% for that of perpendicular within 11% weight loss by oxidation. Thermal diffusivity tended to decrease gradually as the increase of oxidation loss in parallel to lamina, however, it decreased in the beginning of oxidation pretty much and not so changed by further oxidation loss in perpendicular to lamina. The different behavior due to air-oxidation on the thermal diffusivity in two directions was discussed from the fiber and/or matrix texture changes due to air-oxidation. Change in thermal conductivity under oxidation condition was also estimated from the obtained thermal diffusivity. (author)

  14. Xylanase production by Penicillium canescens on soya oil cake in solid-state fermentation.

    Science.gov (United States)

    Antoine, Assamoi Allah; Jacqueline, Destain; Thonart, Philippe

    2010-01-01

    There is an increasing interest for the organic residues from various sectors of agriculture and industries over the past few decades. Their application in the field of fermentation technology has resulted in the production of bulk chemicals and value-added products such as amino acid, enzymes, mushroom, organic acids, single-cell protein, biologically active secondary metabolites, etc. (Ramachandran et al., Bioresource Technology 98:2000-2009, 2007). In this work, the production of extracellular xylanase by the fungus Penicillium canescens was investigated in solid-state fermentation using five agro-industrial substrates (soya oil cake, soya meal, wheat bran, whole wheat bran, and pulp beet). The best substrate was the soya oil cake. In order to optimize the production, the most effective cultivation conditions were investigated in Erlenmeyer flasks and in plastic bags with 5 and 100 g of soya oil cake, respectively. The initial moisture content, initial pH, and temperature of the culture affected the xylanase synthesis. The optimal fermentation medium was composed by soya oil cake crushed to 5 mm supplemented with 3% and 4% (w/w) of casein peptone and Na(2)HPO(4) x 2H(2)O. After 7 days of incubation at 30 degrees C and under 80% of initial moisture, a xylanase production level of 18,895 +/- 778 U/g (Erlenmeyer flasks) and 9,300 +/- 589 U/g (plastic bags) was reached. The partially purified enzyme recovered by ammonium sulfate fractionation was completely stable at freezing and refrigeration temperatures up to 6 months and reasonably stable at room temperature for more than 3 months.

  15. Defect clusters of variable composition as an origin of coloration of oxide crystals under thermal treatment and irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Burachas, S. [RRC ' Kurchatov Institute' , Moscow (Russian Federation); ' North Crystals' Company, Apatity, Murmansk Region (Russian Federation); Ippolitov, M.; Manko, V.; Lomonosov, V.; Nikulin, S.; Vasiliev, A. [RRC ' Kurchatov Institute' , Moscow (Russian Federation); Savelev, Yu. [' North Crystals' Company, Apatity, Murmansk Region (Russian Federation); Apanasenko, A. [Kharkov University, Kharkov (Ukraine); Tamulaitis, G. [IMSAR, Vilnius University, Sauletekio al. 9-III, LT-2040 Vilnius (Lithuania)], E-mail: gintautas.tamulaitis@ff.vu.lt

    2007-04-15

    The dominant role of inclusions of tungsten oxides with variable composition due to variable tungsten valence in the sensitivity of optical absorption of PbWO{sub 4} (PWO) scintillation crystals to thermal treatment and irradiation is demonstrated. A model for processes in the inclusions, which lead to crystal coloration and recovery of initial transparency, is discussed. The deteriorating influence of inclusions containing oxides of variable-valence ions on the radiation hardness of PWO is also illustrated by studying PWO single crystals intentionally doped with niobium. To extend the model to other oxide crystals, annealing of LiNbO{sub 3} single crystals in atmospheres of poor and rich in oxygen was performed, and a reversible coloration of the crystal due to the change of niobium valence in niobium oxide inclusions is demonstrated.

  16. Resistive switching of Cu/Cu2O junction fabricated using simple thermal oxidation at 423 K for memristor application

    Science.gov (United States)

    Ani, M. H.; Helmi, F.; Herman, S. H.; Noh, S.

    2018-01-01

    Recently, extensive researches have been done on memristor to replace current memory storage technologies. Study on active layer of memristor mostly involving n-type semiconductor oxide such as TiO2 and ZnO. This paper highlight a simple water vapour oxidation method at 423 K to form Cu/Cu2O electronic junction as a new type of memristor. Cu2O is a p-type semiconductor oxide, was used as the active layer of memristor. Cu/Cu2O/Au memristor was fabricated by thermal oxidation of copper foil, followed by sputtering of gold. Structural, morphological and memristive properties were characterized using XRD, FESEM, and current-voltage, I-V measurement respectively. Its memristivity was indentified by pinch hysteresis loop and measurement of high resistance state (HRS) and low resistance state (LRS) of the sample. The Cu/Cu2O/Au memristor demonstrates comparable performances to previous studies using other methods.

  17. Real-time observation of initial stages of thermal oxidation on Si(001) surface by using synchrotron radiation photoemission spectroscopy

    CERN Document Server

    Yoshigoe, A; Moritani, K

    2003-01-01

    Real-time observation of initial stages of thermal oxidation processes on the Si(001) surface using O sub 2 gas (1x10 sup - sup 4 Pa) was performed by means of the O-1s and Si-2p photoemission spectroscopy with synchrotron radiation. From the analysis of the time evolution of oxygen uptake curves on the basis of the reaction kinetics model, the oxide-layer growth depending on the surface temperature was categorized by the Langmuir adsorption and the auto-catalytic reaction models, respectively. It was found that the oxidation rates increased with increasing the surface temperature. The time evolution of Si oxidation states depending on the surface temperature was well monitored. We found that the surface temperature enhanced the diffusion and/or migration of adsorbed oxygen and the bulk Si atom. (author)

  18. Thermal and combined thermal and radiolytic reactions involving nitrous oxide, hydrogen, nitrogen, and ammonia in contact with tank 241-SY-101 simulated waste

    International Nuclear Information System (INIS)

    Bryan, S.A.; Pederson, L.R.

    1996-02-01

    Work described in this report was conducted at Pacific Northwest National Laboratory (PNNL) for the Flammable Gas Safety Project, the purpose of which is to develop information needed to support Westinghouse Hanford Company (WHC) in their efforts to ensure the safe interim storage of wastes at the Hanford Site. Described in this report are the results of tests to evaluate the rates of thermal and combined thermal and radiolytic reactions involving flammable gases in the presence of Tank 241-SY-101 simulated waste. Flammable gases generated by the radiolysis of water and by the thermal and radiolytic decomposition of organic waste constituents may themselves participate in further reactions. Examples include the decomposition of nitrous oxide to yield nitrogen and oxygen, the reaction of nitrous oxide and hydrogen to produce nitrogen and water, and the reaction of nitrogen and hydrogen to produce ammonia. The composition of the gases trapped in bubbles in the wastes might therefore change continuously as a function of the time that the gas bubbles are retained

  19. Oxidative Stability of Pomegranate (Punica granatum L.) Seed Oil to Simulated Gastric Conditions and Thermal Stress.

    Science.gov (United States)

    Siano, Francesco; Addeo, Francesco; Volpe, Maria Grazia; Paolucci, Marina; Picariello, Gianluca

    2016-11-09

    The fatty acid composition of pomegranate (Punica granatum L.) seed oil (PSO) is dominated by punicic acid, a conjugated linolenic acid (18:3ω-5). As a free fatty acid, punicic acid is rapidly oxidized in air and extensively isomerizes upon acid-catalyzed methylation at 90 °C. In contrast, triacylglycerol-bound punicic acid in PSO was unchanged by simulated gastric conditions and was degraded by 5-7% by severe heating (up to 170 °C for 4 h), as herein assessed by gas chromatography, attenuated total reflectance-Fourier transform infrared spectroscopy, 1 H and 13 C NMR, and high-resolution electrospray ionization mass spectrometry. Total polar compounds of PSO were slightly affected by thermal stress, accounting for 5.71, 6.35, and 9.53% (w/w) in the unheated, heated at mild temperature (50 °C, 2 h), and heated at frying temperature (170 °C, 4 h) PSO, respectively. These findings support from a structural standpoint the potential use of PSO as a health-promoting edible oil.

  20. Thermal stability of lead sulfide and lead oxide nano-crystalline materials

    Science.gov (United States)

    Nafees, M.; Ikram, M.; Ali, S.

    2017-10-01

    In this study, nano-crystalline lead sulfide (PbS) and lead oxide (PbO) were synthesized using hassle-free and cost-effective chemical route. Lead oxalate (PbC2O4) precursor was thermally decomposed to obtain the nano-crystalline PbO, while PbS nanoparticles were synthesized by microwave irradiation on a mixture of PbC2O4 precursor and sodium thiosulfate. Resulting materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, ultraviolet-visible (UV-Vis) spectrophotometry, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). XRD confirmed the tetragonal structure for PbO and face-centered cubic for PbS with average crystallite sizes varying from 20 to 30 nm for both materials. From UV-Vis spectra, direct band gap energies were calculated to be 2.51 and 2.23 eV for PbO and PbS, respectively. Various decomposition stages during heat treatment of PbO and PbS, as revealed by TGA/DSC, are discussed in detail.

  1. Thermal, mechanical and dielectric properties of poly(vinyl alcohol)/graphene oxide composites

    Science.gov (United States)

    Rathod, Sunil G.; Bhajantri, R. F.; Ravindrachary, V.; Pujari, P. K.; Sheela, T.; Naik, Jagadish

    2014-04-01

    In this work the composite films of poly(vinyl alcohol) (PVA) doped with functionalized Graphene Oxide (GO) were prepared by solution casting method. The films were characterized using FT-IR, DSC, XRD, mechanical properties and dielectric studies at room temperature. FTIR spectra shows the formation of hydrogen bonds between hydroxyl groups of PVA and the hydroxy groups of GO. The DSC thermograms shows the addition of GO to PVA greatly improves the thermal stability of the composites. XRD patterns shows that the GO exfoliated and uniformly dispersed in PVA matrix. Mechanical properties are significantly improved in PVA/GO composites. The tensile strength increased from 8.2 to 13.7 MPa and the Young's modulus increased from 7.5 to 24.8 MPa for 5 wt% GO doped sample. Dielectric spectroscopy showed a highest dielectric constant for the 5 wt% GO doped PVA films. This work provides a potential design strategy on PVA/GO composite, which would lead to higher-performance, flexible dielectric materials, high charge-storage devices.

  2. Radiological protection and dose uptake in the thermal oxide reprocessing plant (Thorp)

    International Nuclear Information System (INIS)

    Kett, P.J.; Clarke, J.S.; Spour, K.P.

    2000-01-01

    British Nuclear Fuels plc has operated the Thermal Oxide Reprocessing Plant (Thorp) for the past 5 years. The plant itself has a history going back over 20 years covering research and development, design, construction, safety assessment and commissioning. Throughout all of these phases a key consideration has been to ensure that the plant offers the highest standards of radiological protection to the workforce. The paper will cover: radiological protection design basis for the plant set against ongoing developments in company internal, national and international guidance; etechnical and engineering methods and systems used to ensure the highest standards of radiological protection; eparation of the workforce from a radiological protection viewpoint, and; details of plant performance from a radiological protection aspect over the first 5 years of plant operation. By following the plant from its inception to full operation the paper will show how a firm design basis, coupled with attention to detail in the areas identified above has allowed a reprocessing plant handling up to 1000 te of fuel per year, irradiated to 40Gwd/te to be successfully operated with average dose uptake to the workforce being kept well below 1 mSv per year. (author)

  3. Thermal properties of poly(ethylene oxide)/lauric acid blends. A SSA-DSC study

    Energy Technology Data Exchange (ETDEWEB)

    Pielichowski, Krzysztof; Flejtuch, Kinga [Department of Chemistry and Technology of Polymers, Cracow University of Technology, ul. Warszawska 24, 31-155 Krakow (Poland)

    2006-03-15

    A series of poly(ethylene oxide) (PEO)/lauric acid blends with different compositions has been prepared and characterised by differential scanning calorimetry (DSC) in dynamic mode. It has been found that the enthalpy of melting and crystallisation reaches its highest value for PEO/lauric acid blend (1:1, w/w) which makes this system a promising candidate for thermal energy storage applications. Further studies by step-scan alternating (SSA)-DSC revealed that an increase of the temperature step causes that the average total heating rate is also increasing and the heat flow is characterised by higher values. Reversing component of the heat flow during melting reaches lowest values at highest step (step=1{sup o}) when the re-crystallisation of PEO is hindered. An increase of step generally leads to an increase of the number of non-equilibrium effects and facilitates the activation of kinetic non-reversing processes, hindering the overall crystallisation of PEO. For lauric acid, due to facile crystallisation and self-association, formation of ordered regular structures takes place faster and is influenced by non-reversing processes in higher proportion. (author)

  4. BNFL's application of computer aided engineering to 'THORP' thermal oxide reprocessing plant

    International Nuclear Information System (INIS)

    Hall-Wilton, M.J.

    1990-01-01

    BNFL are currently constructing facilities at Sellafield, Cumbria to reprocess thermal oxide fuel for U.K., European and Japanese utilities. Faced with a 3.5bn pound capital program to provide new facilities at Sellafield, BNFL took the opportunity to embrace the new computer aided engineering technologies then emerging in 1981. To give some idea of the commitment made by BNFL to the above many millions of pounds has been invested in hardware, and more on software and people. The 'THORP' (Head End and Chemical Separation Plant) project represents 1.5bn pounds. The introduction of computer aided engineering has provided a clash free design with full assurance that all materials and components used are compatible. Planning in the design offices in conjunction with an experienced construction management team enables the sequence of piping installation to be determined long before the construction teams enter the work area. This planning aspect has been significantly improved by using EVS (Enhanced Visualisation System). The use of supercomputing graphics facilities is stimulating demands from areas of engineering who have previously not sought to use magnetic data from a variety of sources. The result is mainly due to the data being easily accessible to users who have very little computing experience. (N.K.)

  5. Effect of Thermally Reduced Graphene Oxide on Mechanical Properties of Woven Carbon Fiber/Epoxy Composite

    Directory of Open Access Journals (Sweden)

    Nitai Chandra Adak

    2018-02-01

    Full Text Available Thermally reduced graphene oxide (TRGO was incorporated as a reinforcing filler in the epoxy resin to investigate the effect on the mechanical properties of carbon fiber (CF/epoxy composites. At first, the epoxy matrix was modified by adding different wt % of TRGO from 0.05 to 0.4 wt % followed by the preparation of TRGO/CF/epoxy composites througha vacuum-assisted resin transfer molding process. The prepared TRGO was characterized by using Fourier transform infrared spectroscopy, Raman Spectroscopy and field emission scanning electron microscopy (FE-SEM techniques. It was observed that the wrinkled structure of synthesized TRGO may be helpful to interlock with the epoxy resin and CF.The inter-laminar shear strength, in-plane fracture toughness and impact strength increased by ~67%, 62% and 93% at 0.2 wt % of TRGO loading in the CF/epoxy composites as compared to the CF reinforced epoxy. The mechanical properties of the hybrid composites decreased beyond the 0.2 wt % of TRGO incorporation in the epoxy resin. The fracture surfaces of the hybrid composites were studied by FE-SEM image analysis to investigate the synergistic effect of TRGO in the CF/epoxy composite. This study suggested that TRGO could be used asgood nanofiller to resist the matrix and fiber fracture.

  6. Metal-catalyzed growth of In2O3 nanotowers using thermal evaporation and oxidation method

    Science.gov (United States)

    Jian, Liu; Shihua, Huang; Lü, He

    2015-12-01

    Large-scale In2O3 nanotowers with different cross sections were synthesized by a thermal evaporation and oxidation technique using metal as the catalyst. The morphologies and structural characterizations of In2O3 nanotowers are dependent on growth processes, such as different metal (Au, Ag or Sn) catalysts, the relative position of the substrate and evaporation source, growth temperature, gas flow rate, and growth time. In2O3 nanotowers cannot be observed using Sn as the catalyst, which indicates that metal liquid droplets play an important role in the initial stages of the growth of In2O3 nanotowers. The formation of an In2O3 nanotower is attributed to the competitive growth model between a lateral growth controlled by vapor-solid mechanism and an axial vapor-liquid-solid growth mechanism mediated by metal liquid nanodroplets. The synthesized In2O3 nanostructures with novel tower-shaped morphology may have potential applications in optoelectronic devices and gas sensors. Project supported by the National Natural Science Foundation of China (No. 61076055), the Open Project Program of Surface Physics Laboratory (National Key Laboratory) of Fudan University (No. KF2015_02), the Zhejiang Provincial Science and Technology Key Innovation Team (No. 2011R50012), and the Zhejiang Provincial Key Laboratory (No. 2013E10022).

  7. Solvent or thermal extraction of ethylene oxide from polymeric materials: Medical device considerations.

    Science.gov (United States)

    Lucas, Anne D; Forrey, Christopher; Saylor, David M; Vorvolakos, Katherine

    2017-12-11

    Ethylene oxide (EO) gas is commonly used to sterilize medical devices. Bioavailable residual EO, however, presents a significant toxicity risk to patients. Residual EO is assessed using international standards describing extraction conditions for different medical device applications. We examine a series of polymers and explore different extraction conditions to determine residual EO. Materials were sterilized with EO and exhaustively extracted in water, in one of three organic solvents, or in air using thermal desorption. The EO exhaustively extracted varies significantly and is dictated by two factors: the EO that permeates the material during sterilization; and the effectiveness of the extraction protocol in flushing residual EO from the material. Extracted EO is maximized by a close matches between Hildebrand solubility parameters δ polymer , δ EO , and δ solvent . There remain complexities to resolve, however, because maximized EO uptake and detection are accompanied by great variability. These observations may inform protocols for material selection, sterilization, and EO extraction. 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

  8. Thermal sensitivity of carbon nanotube and graphene oxide containing responsive hydrogels

    Directory of Open Access Journals (Sweden)

    E. Manek

    2016-08-01

    Full Text Available Comparative investigations are reported on poly(N-isopropylacrylamide (PNIPA gels of various carbon nanotube (CNT and graphene oxide (GO contents synthesized under identical conditions. The kind and concentration of the incorporated carbon nanoparticles (CNPs influence the swelling and stress-strain behaviour of the composites. Practically independently of the filler content, incorporation of CNPs appreciably improves the fracture stress properties of the gels. The time constant and the swelling ratio of the shrinkage following an abrupt increase in temperature of the swelling medium from 20 to 50 °C can be adjusted by selecting both the type and the amount of nanoparticle loading. This offers a means of accurately controlling the deswelling kinetics of drug release with PNIPA systems, and could be employed in sensor applications where fast and excessive shrinkage are a significant drawback. Both CNTs and GO enhance the infrared sensitivity of the PNIPA gel, thus opening a route for the design of novel drug transport and actuator systems. It is proposed that the influence of the CNPs depends more on their surface reactivity during the gel synthesis rather than on their morphology. One of the important findings of this study is the existence of a thermally conducting network in the GO filled gels.

  9. Non-thermal hydrogen plasma processing effectively increases the antibacterial activity of graphene oxide

    Science.gov (United States)

    Ke, Zhigang; Ma, Yulong; Zhu, Zhongjie; Zhao, Hongwei; Wang, Qi; Huang, Qing

    2018-01-01

    Graphene-based materials (GMs) are promising antibacterial agents which provide an alternative route to treat pathogenic bacteria with resistance to conventional antibiotics. To further improve their antibacterial activity, many methods have been developed to functionalize the GMs with chemicals. However, the application of additional chemicals may pose potential risks to the environment and human being. Herein, a radio-frequency-driven inductively coupled non-thermal hydrogen plasma was used to treat and reduce graphene oxide (GO) without using any other chemicals, and we found that the plasma-reduced GO (prGO) is with significantly higher bactericidal activity against Escherichia coli. The mechanism of the increased antibacterial activity of prGO is due to that plasma processing breaks down the GO sheets into smaller layers with more rough surface defects, which can thus induce more destructive membrane damages to the bacteria. This work sets another good example, showing that plasma processing is a green and low-cost alternative for GM modification for biomedical applications.

  10. Processing of converter sludges on the basis of thermal-oxidative coking with coals

    Science.gov (United States)

    Kuznetsov, S. N.; Shkoller, M. B.; Protopopov, E. V.; Kazimirov, S. A.; Temlyantsev, M. V.

    2017-09-01

    The paper deals with the solution of an important problem related to the recycling of converter sludge. High moisture and fine fractional composition of waste causes the application of their deep dehydration and lumping. To reduce environmental emissions the non-thermal method of dehydration is considered - adsorption-contact drying. As a sorbent, the pyrolysis product of coals from the Kansko-Achinsky basin - brown coal semi-coke (BSC) obtained by the technology “Thermokoks”. Experimental data on the dehydration of high-moisture wastes with the help of BSC showed high efficiency of the selected material. The lumping of the dried converter dust was carried out by thermo-chemical coking with coals of grades GZh (gas fat coal) and Zh (fat coal). As a result, an iron-containing product was obtained - ferrocoke, which is characterized by almost complete reduction of iron oxides, as well as zinc transition into a vapor state, and is removed with gaseous process products. Based on the results of the experimental data a process basic diagram of the utilization of converter sludge to produce ferrocoke was, which can be effectively used in various metallurgical aggregates, for example, blast furnaces, converters and electric arc furnaces. In the basic technological scheme heat generated by ferrocoke cooling and the energy of the combustion products after the separation of zinc in the gas turbine plant will be used.

  11. Investigation of thermal conductivity and oxidation behaviour of reaction bonded aluminum nitride (RBAN) ceramics

    International Nuclear Information System (INIS)

    Salahi, E; Moztarzadeh, F.; Margoosian, V.; Heinrich, J. G.

    2003-01-01

    AlN samples have been produced by reaction bonding process using AlN and aluminum powders as starting materials. Different aluminum nitride and aluminum powders ratios were mixed in ethanol media, dried, isostatically and nitrided in (N 2 )atmosphere. Results showed that conversion of to AlN depends strongly on the amount of aluminum starting powder and decreased with increasing after a maximum at 25 Al wt %. Changing the particle size and morphology of the aluminum starting powder leads to change in the conversion ratio and microstructure of RBAN ceramics. Typical scanning electron micrographs of RBAN sample indicating primary and secondary aluminum nitride morphology and pore structure. The oxidation behavior of RABN samples showed the weight gain depends on the average particle size, morphology and amount of Al in starting mixture and pore structure. Samples have been manufactured with equi-axed morphology of Al starting powder have thermal conductivity higher than the samples have been manufactured with flake-like morphology. These differences were directly related to the different microstructure of RBAN samples

  12. Determination of acetaminophen's solubility in poly(ethylene oxide) by rheological, thermal and microscopic methods.

    Science.gov (United States)

    Yang, Min; Wang, Peng; Suwardie, Herman; Gogos, Costas

    2011-01-17

    A drug's solubility in a polymeric excipient is an important parameter that dictates the process window of hot-melt extrusion (HME) and product stability during storage. However, it is rather challenging to experimentally determine the solubility and there is very few published work in this field. In this study, the solubility of a model drug acetaminophen (APAP) in a pharmaceutical grade polymer poly(ethylene oxide) (PEO) at HME processing temperature was measured utilizing rheological analysis, hot-stage microscopy and differential scanning calorimetry (DSC). The results from three methods were consistent and the solubility was found to increase from 14% at 80°C to 41% at 140°C. The apparent drug solubility at room temperature was estimated to be less than 10% through glass transition temperature (T(g)) measurement using DSC and dynamic mechanical thermal analysis (DMTA). A "phase diagram" was constructed based on the experimental data and could be explored to design the HME process and formulation. Very few assumptions were made in the experimental study and result analysis, and the methods described here can be applied to investigate other drug-polymer systems to obtain the important thermodynamic data. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Evaluation of Residence Time on Nitrogen Oxides Removal in Non-Thermal Plasma Reactor

    Science.gov (United States)

    Talebizadeh, Pouyan; Rahimzadeh, Hassan; Babaie, Meisam; Javadi Anaghizi, Saeed; Ghomi, Hamidreza; Ahmadi, Goodarz; Brown, Richard

    2015-01-01

    Non-thermal plasma (NTP) has been introduced over the last few years as a promising after- treatment system for nitrogen oxides and particulate matter removal from diesel exhaust. NTP technology has not been commercialised as yet, due to its high rate of energy consumption. Therefore, it is important to seek out new methods to improve NTP performance. Residence time is a crucial parameter in engine exhaust emissions treatment. In this paper, different electrode shapes are analysed and the corresponding residence time and NOx removal efficiency are studied. An axisymmetric laminar model is used for obtaining residence time distribution numerically using FLUENT software. If the mean residence time in a NTP plasma reactor increases, there will be a corresponding increase in the reaction time and consequently the pollutant removal efficiency increases. Three different screw thread electrodes and a rod electrode are examined. The results show the advantage of screw thread electrodes in comparison with the rod electrode. Furthermore, between the screw thread electrodes, the electrode with the thread width of 1 mm has the highest NOx removal due to higher residence time and a greater number of micro-discharges. The results show that the residence time of the screw thread electrode with a thread width of 1 mm is 21% more than for the rod electrode. PMID:26496630

  14. Evaluation of Residence Time on Nitrogen Oxides Removal in Non-Thermal Plasma Reactor.

    Directory of Open Access Journals (Sweden)

    Pouyan Talebizadeh

    Full Text Available Non-thermal plasma (NTP has been introduced over the last few years as a promising after- treatment system for nitrogen oxides and particulate matter removal from diesel exhaust. NTP technology has not been commercialised as yet, due to its high rate of energy consumption. Therefore, it is important to seek out new methods to improve NTP performance. Residence time is a crucial parameter in engine exhaust emissions treatment. In this paper, different electrode shapes are analysed and the corresponding residence time and NOx removal efficiency are studied. An axisymmetric laminar model is used for obtaining residence time distribution numerically using FLUENT software. If the mean residence time in a NTP plasma reactor increases, there will be a corresponding increase in the reaction time and consequently the pollutant removal efficiency increases. Three different screw thread electrodes and a rod electrode are examined. The results show the advantage of screw thread electrodes in comparison with the rod electrode. Furthermore, between the screw thread electrodes, the electrode with the thread width of 1 mm has the highest NOx removal due to higher residence time and a greater number of micro-discharges. The results show that the residence time of the screw thread electrode with a thread width of 1 mm is 21% more than for the rod electrode.

  15. Evaluation of Residence Time on Nitrogen Oxides Removal in Non-Thermal Plasma Reactor.

    Science.gov (United States)

    Talebizadeh, Pouyan; Rahimzadeh, Hassan; Babaie, Meisam; Javadi Anaghizi, Saeed; Ghomi, Hamidreza; Ahmadi, Goodarz; Brown, Richard

    2015-01-01

    Non-thermal plasma (NTP) has been introduced over the last few years as a promising after- treatment system for nitrogen oxides and particulate matter removal from diesel exhaust. NTP technology has not been commercialised as yet, due to its high rate of energy consumption. Therefore, it is important to seek out new methods to improve NTP performance. Residence time is a crucial parameter in engine exhaust emissions treatment. In this paper, different electrode shapes are analysed and the corresponding residence time and NOx removal efficiency are studied. An axisymmetric laminar model is used for obtaining residence time distribution numerically using FLUENT software. If the mean residence time in a NTP plasma reactor increases, there will be a corresponding increase in the reaction time and consequently the pollutant removal efficiency increases. Three different screw thread electrodes and a rod electrode are examined. The results show the advantage of screw thread electrodes in comparison with the rod electrode. Furthermore, between the screw thread electrodes, the electrode with the thread width of 1 mm has the highest NOx removal due to higher residence time and a greater number of micro-discharges. The results show that the residence time of the screw thread electrode with a thread width of 1 mm is 21% more than for the rod electrode.

  16. The preparation of cerium oxide by thermal decomposition and the determination of the particle characteristics

    International Nuclear Information System (INIS)

    Horsley, S.; Towner, J.M.; Waldron, M.B.

    1975-01-01

    Cerium IV oxides were prepared by selective thermal treatment of Cerium III oxalate. The ''activity'' of these powders was assessed by several techniques including gas adsorption, X-ray line broadening, differential scanning calorimetry, electron microscopy, and heterogeneous catalysis studies. The compaction and the initial sintering stages of fine powders are known to be affected by the absolute particle size, the surface chemistry and the structure of the material. The general concept of ''activity'' has been used to describe the effects of these properties on the behavior of powder compacts. In this work the degree of interrelation between several possible causes of ''activity'' are explored. The variation in the amount of energy stored in the surface and the bulk of differently prepared powders is considered in relation to the probable mode of solid state decomposition of the oxalate salt. The possibility of measuring the release of such ''strain'' energies is discussed. The influence of lattice disorder on the heterogeneous catalysis properties of the powders is also considered

  17. Relationships among thermal stress, bleaching and oxidative damage in the hermatypic coral, Pocillopora capitata.

    Science.gov (United States)

    Flores-Ramírez, Laura A; Liñán-Cabello, Marco A

    2007-01-01

    To examine the response to exposure to a thermal gradient in coral, we assessed the effect of a gradual 10 degrees C temperature increase (22 to 32 degrees C over 10 h) on normal (N), partially bleached (P) and control (C) samples collected from different branches of the same coral (Pocillopora capitata). We examined markers of oxidative stress, including lipid peroxidation (MDA) and superoxide dismutase (SOD) activity, indicators of bleaching, including chlorophyll a (Chl a) and carotenoid pigment (PC) levels, as well as zooxanthellae density. Our results revealed that N, P and C coral samples all contained higher levels of PC versus Chl a. The levels of both pigments increased as the temperature increased from 22 to 28 degrees C only in N and C samples, whereas P samples showed less cellular damage than N and C samples at temperatures between 26 and 28 degrees C, and had greater antioxidant activities at temperatures between 26 and 30 degrees C. The rate of zooxanthellar expulsion consistently increased with temperature in all three coral types across the entire temperature range. Collectively, these results indicate that temperature has a direct effect on the antagonistic relationship between temperature-induced damage and protective antioxidant mechanisms in this type of coral.

  18. Structure evolution of graphene oxide during thermally driven phase transformation: is the oxygen content really preserved?

    Directory of Open Access Journals (Sweden)

    Pengzhan Sun

    Full Text Available A mild annealing procedure was recently proposed for the scalable enhancement of graphene oxide (GO properties with the oxygen content preserved, which was demonstrated to be attributed to the thermally driven phase separation. In this work, the structure evolution of GO with mild annealing is closely investigated. It reveals that in addition to phase separation, the transformation of oxygen functionalities also occurs, which leads to the slight reduction of GO membranes and furthers the enhancement of GO properties. These results are further supported by the density functional theory based calculations. The results also show that the amount of chemically bonded oxygen atoms on graphene decreases gradually and we propose that the strongly physisorbed oxygen species constrained in the holes and vacancies on GO lattice might be responsible for the preserved oxygen content during the mild annealing procedure. The present experimental results and calculations indicate that both the diffusion and transformation of oxygen functional groups might play important roles in the scalable enhancement of GO properties.

  19. Effect of thermal implying during ageing process of nanorods growth on the properties of zinc oxide nanorod arrays

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, A. S., E-mail: kyrin-samaxi@yahoo.com; Mamat, M. H., E-mail: mhmamat@salam.uitm.edu.my; Rusop, M., E-mail: rusop@salam.uitm.my [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia); Malek, M. F., E-mail: firz-solarzelle@yahoo.com; Abdullah, M. A. R., E-mail: ameerridhwan89@gmail.com; Sin, M. D., E-mail: diyana0366@johor.uitm.edu.my [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia)

    2016-07-06

    Undoped and Sn-doped Zinc oxide (ZnO) nanostructures have been fabricated using a simple sol-gel immersion method at 95°C of growth temperature. Thermal sourced by hot plate stirrer was supplied to the solution during ageing process of nanorods growth. The results showed significant decrement in the quality of layer produced after the immersion process where the conductivity and porosity of the samples reduced significantly due to the thermal appliance. The structural properties of the samples have been characterized using field emission scanning electron microscopy (FESEM) electrical properties has been characterized using current voltage (I-V) measurement.

  20. Thermal cyclic oxidation behavior of the developed compositionally gradient graphite material of SiC/C in air environment

    International Nuclear Information System (INIS)

    Nakano, Junichi; Fujii, Kimio; Shindo, Masami

    1993-08-01

    For the developed compositionally gradient graphite material composed of surface SiC coating layer, middle SiC/C layer and graphite matrix, the thermal cyclic oxidation test was performed together with two kinds of the SiC coated graphite materials in air environment. It was made clear that the developed material exhibited high performance under severe thermal cyclic condition independent of the morphology of middle SiC/C layers and had the longer time or the more cycle margins from crack initiation to failure for surface SiC coating layer compared with the SiC coated graphite materials. (author)

  1. Effect of thermal implying during ageing process of nanorods growth on the properties of zinc oxide nanorod arrays

    International Nuclear Information System (INIS)

    Ismail, A. S.; Mamat, M. H.; Rusop, M.; Malek, M. F.; Abdullah, M. A. R.; Sin, M. D.

    2016-01-01

    Undoped and Sn-doped Zinc oxide (ZnO) nanostructures have been fabricated using a simple sol-gel immersion method at 95°C of growth temperature. Thermal sourced by hot plate stirrer was supplied to the solution during ageing process of nanorods growth. The results showed significant decrement in the quality of layer produced after the immersion process where the conductivity and porosity of the samples reduced significantly due to the thermal appliance. The structural properties of the samples have been characterized using field emission scanning electron microscopy (FESEM) electrical properties has been characterized using current voltage (I-V) measurement.

  2. Effects of thermal treatment on mineralogy and heavy metal behavior in iron oxide stabilized air pollution control residues

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Bender-Koch, C.; Starckpoole, M. M.

    2000-01-01

    Stabilization of air pollution control residues by coprecipitation with ferrous iron and subsequent thermal treatment (at 600 and 900 °C) has been examined as a means to reduce heavy metal leaching and to improve product stability. Changes in mineralogy and metal binding were analyzed using various...... volatilized or destabilized with respect to leaching. Pb, in particular, exhibited increased reactivity following the formation of an ordered iron oxide structure at 900 °C. The thermal treatment had a positive effect on Cr release, which was reduced significantly at 900 °C in the presence of organic matter...

  3. Mechanical Reinforcement, Shapestabilization and Thermal Improvement of Phase-Change Energy Storage Materials Using Graphene Oxide Aerogel

    Science.gov (United States)

    Schuman, Yue Xu

    Paraffin is known as a good energy storage phase change material (PCM) because of its high energy storage capacity and low cost. However, the leakage of liquid paraffin beyond its melting point and its low thermal conductivity hinder applications of paraffin in energy storage systems. Recently, nanomaterials have been used to create PCM composites in order to enhance their thermal properties while shape stabilizing the PCMs. However, fundamental studies on the material structures and mechanical behavior of the thermally enhanced PCM composites are limited especially at the nanoscale. In this study, we developed a PCM composite using graphene oxide aerogel (GOxA) as the reinforcing 3D network. The GOxA functions thermally as a heat transfer path and mechanically as a nanofiller to reinforce the PCM matrix. We characterized the morphology, the crystal and molecular structures as well as the multiscale mechanical and thermal behavior of the GOxA-PCM composite to evaluate the role of GOxA in the PCM composite. The molecular and diffraction characterizations imply that the GOxA network may affect the paraffin's crystallization, potentially forming an interfacial phase at the surfaces of GOxA. Furthermore, the mechanical properties were studied using nanoindentation at the nano/microscale and a digital durometer at the macroscale from 25degree C to 80 degree C. The mechanical characterizations show that the GOxA-PCM composite is 3 7x harder than pure paraffin and maintains significant strength even above paraffin's melting point due to the support from the GoxA. Moreover, the composite is much less strain-rate sensitive than paraffin. The reinforcement via GOxA is much beyond the prediction by the rule of mixture, implying a strong GOxA-paraffin interfacial bonding. Finally, a thermal scanning microscopy (SThM) along with AFM was used to study the thermal properties at microscale. AFM and thermal images indicate that GOxA-PCM has a better thermal conductivity. The latent

  4. Fermentation of calcium-fortified soya milk does not appear to enhance acute calcium absorption in osteopenic post-menopausal women.

    Science.gov (United States)

    Cheung, Anne Lise Tang Fook; Wilcox, Gisela; Walker, Karen Z; Shah, Nagendra P; Strauss, Boyd; Ashton, John F; Stojanovska, Lily

    2011-01-01

    Ageing women may choose to drink soya milk to reduce menopausal symptoms. As fermentation enriches soya milk with isoflavone aglycones, its beneficial qualities may improve. To reduce osteoporotic risk, however, soya milk must be Ca enriched, and it is not known how fermentation affects Ca bioavailability. A randomised crossover pilot study was undertaken to compare the Ca absorption of fortified soya milk with that of fermented and fortified soya milk in twelve Australian osteopenic post-menopausal women. The fortified soya milk was inoculated with Lactobacillus acidophilus American Type Culture Collection (ATCC) 4962 and fermented for 24 h at 37°C. Ca absorption from soya milk samples was measured using a single isotope radiocalcium method. Participants had a mean age of 54·8 (sd 12·3) years, with mean BMI of 26·5 (sd 5·5) kg/m2 and subnormal to normal serum 25-hydroxyvitamin D (mean 62·5 (sd 19·1) nmol/l). Participants consumed 185 kBq of 45Ca in 44 mg of Ca carrier. The mean fractional Ca absorption (α) from soya milk and fermented soya milk was 0·64 (sd 0·23) and 0·71 (sd 0·29), respectively, a difference not of statistical significance (P = 0·122). Although fermentation of soya milk may provide other health benefits, fermentation had little effect on acute Ca absorption.

  5. Experimental investigation of the flow, oxidation, cooling, and thermal-fatigue characteristics of a laminated porous sheet material

    Science.gov (United States)

    Hickel, R. O.; Warren, E. L.; Kaufman, A.

    1972-01-01

    The basic flow and oxidation characteristics of a laminated porous material (Lamilloy) are presented. The oxidation characteristics of Lamilloy are compared to a wireform-type porous material for the case when both materials are made from Hastelloy-X alloy. The cooling performance of an air cooled vane made from Lamilloy, as determined from cascade tests made at gas temperatures ranging from 1388 to 1741 C (2350 to 3165 F) is also discussed, as well as of a cascade-type thermal fatigue test of the Lamilloy vane.

  6. Characterization of Thermal Oxides on 4H-SiC Epitaxial Substrates Using Fourier-Transform Infrared Spectroscopy.

    Science.gov (United States)

    Seki, Hirofumi; Yoshikawa, Masanobu; Kobayashi, Takuma; Kimoto, Tsunenobu; Ozaki, Yukihiro

    2017-05-01

    Fourier transform infrared (FT-IR) spectra were measured for thermal oxides with different electrical properties grown on 4H-SiC substrates. The peak frequency of the transverse optical (TO) phonon mode was blue-shifted by 5 cm -1 as the oxide-layer thickness decreased to 3 nm. The blue shift of the TO mode indicates interfacial compressive stress in the oxide. Comparison of data for the oxide on a SiC substrate with that for similar oxides on a Si substrate implies that the peak shift of the TO mode at the SiO 2 /SiC interface is larger than that of SiO 2 /Si, which suggests that the interfacial stress for the oxide on the SiC substrate is larger than that on the Si substrate. For the SiO 2 /SiC interfacial region (Fourier transform infrared spectroscopy measurements provide unique and useful information about stress and inhomogeneity at the oxide/SiC interface.

  7. Effects of thermal oxidation duration on the structural and electrical properties of Nd2O3/Si system

    Science.gov (United States)

    Hetherin, Karuppiah; Ramesh, S.; Wong, Yew Hoong

    2017-08-01

    A study on the growth, structure and electrical properties of Nd2O3 was carried out experimentally on RF sputtered thin film on Si followed by thermal oxidation at 700 °C at different oxidation durations (5, 10, 15 and 20 min). The structural and chemical properties were studied by X-ray diffraction analysis, Fourier transform infrared analysis, Raman analysis and high resolution transmission electron microscopy analysis. The formation of cubic-Nd2O3, orthorhombic-Nd2Si2O7, monoclinic-SiO2, tetragonal-SiO2 and hexagonal-SiO2 was detected. A single interfacial layer was detected for the sample oxidized at 15 min and double interfacial layers were detected for the samples oxidized at 5, 10 and 20 min. The sample oxidized at 15 min possessed the best electrical properties which were attributed by the highest Nd2O3 intensity, largest SiO2 crystallite structure, thinnest interfacial and oxide layer, highest barrier height, lowest effective oxide charges, slow trap density and average interface trap density.

  8. Thermal Effect on the Structural, Electrical, and Optical Properties of In-Line Sputtered Aluminum Doped Zinc Oxide Films Explored with Thermal Desorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    Shang-Chou Chang

    2014-01-01

    Full Text Available This work investigates the thermal effect on the structural, electrical, and optical properties of aluminum doped zinc oxide (AZO films. The AZO films deposited at different temperatures were measured using a thermal desorption system to obtain their corresponding thermal desorption spectroscopy (TDS. In addition to obtaining information of thermal desorption, the measurement of TDS also has the effect of vacuum annealing on the AZO films. The results of measuring TDS imply part of the doped aluminum atoms do not stay at substituted zinc sites in AZO films. The (002 preferential direction of the AZO films in X-ray diffraction spectra shifts to a lower angle after measurement of TDS. The grain size grows and surface becomes denser for all AZO films after measurement of TDS. The carrier concentration, mobility, and average optical transmittance increase while the electrical resistivity decreases for AZO films after measurement of TDS. These results indicate that the AZO films deposited at 200°C are appropriate selections if the AZO films are applied in device fabrication of heat-produced process.

  9. Multilayered thermal insulation formed of zirconia bonded layers of zirconia fibers and metal oxide fibers and method for making same

    Science.gov (United States)

    Wrenn, Jr., George E.; Holcombe, Jr., Cressie E.

    1988-01-01

    A multilayered thermal insulating composite is formed of a first layer of zirconia-bonded zirconia fibers for utilization near the hot phase or surface of a furnace or the like. A second layer of zirconia-bonded metal oxide fibers is attached to the zirconia fiber layer by a transition layer formed of intermingled zirconia fibers and metal oxide fibers. The thermal insulation is fabricated by vacuum molding with the layers being sequentially applied from aqueous solutions containing the fibers to a configured mandrel. A portion of the solution containing the fibers forming the first layer is intermixed with the solution containing the fibers of the second layer for forming the layer of mixed fibers. The two layers of fibers joined together by the transition layer are saturated with a solution of zirconium oxynitrate which provides a zirconia matrix for the composite when the fibers are sintered together at their nexi.

  10. Electrochemical and thermal properties of polymer electrolytes based on poly(epichlorohydrin-co-ethylene oxide-co-ally glycidyl ether)

    International Nuclear Information System (INIS)

    Rodrigues, L.C.; Barbosa, P.C.; Silva, M.M.; Smith, M.J.

    2007-01-01

    A series of novel electrolytes based on the terpolymer host, poly(epichlorohydrin-co-ethylene oxide-co-allyl glycidyl ether) with lithium perchlorate and lithium bis(trifluoromethanesulfonyl)imide have been prepared and characterized by conductivity measurements, cyclic voltammetry at a gold microelectrode and thermal analysis. Electrolyte compositions, represented as p(EEO-AGE)LiX(wt%), were produced with lithium salt compositions between 0.5 and 53 wt% (where wt% indicates amount of lithium salt present in the epichlorohydrin-co-ethylene oxide-co-allyl glycidyl host matrix). The guest salt and host polymer were dissolved in tetrahydrofuran and cast to produce thin, free-standing electrolyte films. The p(EEO-AGE)LiX(wt%) (X = ClO 4 and TFSI) electrolytes showed encouraging levels of ionic conductivity and acceptable thermal stability. Electrolytes based on this host polymer were obtained as completely amorphous films with good mechanical properties

  11. Removal of Iron Oxide Scale from Feed-water in Thermal Power Plant by Using Magnetic Separation

    Science.gov (United States)

    Nakanishi, Motohiro; Shibatani, Saori; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro

    2017-09-01

    One of the factors of deterioration in thermal power generation efficiency is adhesion of the scale to inner wall in feed-water system. Though thermal power plants have employed All Volatile Treatment (AVT) or Oxygen Treatment (OT) to prevent scale formation, these treatments cannot prevent it completely. In order to remove iron oxide scale, we proposed magnetic separation system using solenoidal superconducting magnet. Magnetic separation efficiency is influenced by component and morphology of scale which changes their property depending on the type of water treatment and temperature. In this study, we estimated component and morphology of iron oxide scale at each equipment in the feed-water system by analyzing simulated scale generated in the pressure vessel at 320 K to 550 K. Based on the results, we considered installation sites of the magnetic separation system.

  12. Thermal Treatment of Iron Oxide Stabilized APC Residues from Waste Incineration and the Effect on Heavy Metal Binding

    DEFF Research Database (Denmark)

    Sørensen, Mette Abildgaard; Stackpoole, M.; Bender-Koch, C.

    2000-01-01

    Iron oxide stabilized APC residues from MSWI were heat treated at 600°C and 900°C. The thermal treatments resulted in a change in product stability by forcing a transformation in the mineralogical structures of the products. The treatments, moreover, simulated somewhat the natural aging processes...... that would take place in a stabilized residue. Consequent changes in crystalline structure and heavy metal binding were examined....

  13. Fabrication of ammonium perchlorate/copper-chromium oxides core-shell nanocomposites for catalytic thermal decomposition of ammonium perchlorate

    Energy Technology Data Exchange (ETDEWEB)

    Eslami, Abbas, E-mail: eslami@umz.ac.ir [Department of Inorganic Chemistry, Faculty of Chemistry, University of Mazandaran, P.O.Box 47416-95447, Babolsar (Iran, Islamic Republic of); Juibari, Nafise Modanlou [Department of Inorganic Chemistry, Faculty of Chemistry, University of Mazandaran, P.O.Box 47416-95447, Babolsar (Iran, Islamic Republic of); Hosseini, Seyed Ghorban [Department of Chemistry, Malek Ashtar University of Technology, P.O. Box 16765-3454, Tehran (Iran, Islamic Republic of)

    2016-09-15

    The ammonium perchlorate/Cu(II)-Cr(III)-oxides(AP/Cu-Cr-O) core-shell nanocomposites were in-situ prepared by deposition of copper and chromium oxides on suspended ammonium perchlorate particles in ethyl acetate as solvent. The results of differential scanning calorimetery (DSC) and thermal gravimetric analysis (TGA) experiments showed that the nanocomposites have excellent catalytic effect on the thermal decomposition of AP, so that the released heat increases up to about 3-fold over initial values, changing from 450 J/g for pure AP to 1510 J/g for most appropriate mixture. For better comparison, single metal oxide/AP core-shell nanocomposite have also been prepared and the results showed that they have less catalytic effect respect to mixed metal oxides system. Scanning electron microscopy (SEM) results revealed homogenous deposition of nanoparticles on the surface of AP and fabrication of core-shell structures. The kinetic parameters of thermal decomposition of both pure AP and AP/Cu-Cr-O samples have been calculated by Kissinger method and the results showed that the values of pre-exponential factor and activation energy are higher for AP/Cu-Cr-O nanocomposite. The better catalytic effect of Cu-Cr-O nanocomposites is probably attributed to the synergistic effect between Cu{sup 2+} and Cr{sup 3+} in the nanocomposites, smaller particle size and more crystal defect. - Highlights: • The Cu-Cr-O nanoparticles were synthesized by chemical liquid deposition method. • Then, the AP/Cu-Cr-O core-shell nanocomposites were prepared. • The core-shell samples showed high catalytic activity for AP decomposition. • Thermal decomposition of samples occurs at lower temperature range.

  14. Fabrication of ammonium perchlorate/copper-chromium oxides core-shell nanocomposites for catalytic thermal decomposition of ammonium perchlorate

    International Nuclear Information System (INIS)

    Eslami, Abbas; Juibari, Nafise Modanlou; Hosseini, Seyed Ghorban

    2016-01-01

    The ammonium perchlorate/Cu(II)-Cr(III)-oxides(AP/Cu-Cr-O) core-shell nanocomposites were in-situ prepared by deposition of copper and chromium oxides on suspended ammonium perchlorate particles in ethyl acetate as solvent. The results of differential scanning calorimetery (DSC) and thermal gravimetric analysis (TGA) experiments showed that the nanocomposites have excellent catalytic effect on the thermal decomposition of AP, so that the released heat increases up to about 3-fold over initial values, changing from 450 J/g for pure AP to 1510 J/g for most appropriate mixture. For better comparison, single metal oxide/AP core-shell nanocomposite have also been prepared and the results showed that they have less catalytic effect respect to mixed metal oxides system. Scanning electron microscopy (SEM) results revealed homogenous deposition of nanoparticles on the surface of AP and fabrication of core-shell structures. The kinetic parameters of thermal decomposition of both pure AP and AP/Cu-Cr-O samples have been calculated by Kissinger method and the results showed that the values of pre-exponential factor and activation energy are higher for AP/Cu-Cr-O nanocomposite. The better catalytic effect of Cu-Cr-O nanocomposites is probably attributed to the synergistic effect between Cu 2+ and Cr 3+ in the nanocomposites, smaller particle size and more crystal defect. - Highlights: • The Cu-Cr-O nanoparticles were synthesized by chemical liquid deposition method. • Then, the AP/Cu-Cr-O core-shell nanocomposites were prepared. • The core-shell samples showed high catalytic activity for AP decomposition. • Thermal decomposition of samples occurs at lower temperature range.

  15. Optimum Conditions for Effective Decomposition of Toluene as VOC Gas by Pilot-Scale Regenerative Thermal Oxidizer

    OpenAIRE

    S. Iijima; K. Nakayama; D. Kuchar; M. Kubota; H. Matsuda

    2008-01-01

    Regenerative Thermal Oxidizer (RTO) is one of the best solutions for removal of Volatile Organic Compounds (VOC) from industrial processes. In the RTO, VOC in a raw gas are usually decomposed at 950-1300 K and the combustion heat of VOC is recovered by regenerative heat exchangers charged with ceramic honeycombs. The optimization of the treatment of VOC leads to the reduction of fuel addition to VOC decomposition, the minimization of CO2 emission and operating cost as wel...

  16. Advanced Oxide Material Systems for 1650 Deg. C Thermal/Environmental Barrier Coating Applications

    National Research Council Canada - National Science Library

    Zhu, Dongming; Fox, Dennis S; Bansal, Narottam P; Miller, Robert A

    2004-01-01

    ... systems under engine high-heat-flux and severe thermal cycling conditions. In this report, the thermal conductivity and water vapor stability of selected candidate hafnia-, pyrochlore-, and magnetoplumbite-based TEBC materials are evaluated...

  17. Interaction of sodium diclofenac with freeze-dried soya phosphatidylcholine and unilamellar liposomes Interação do diclofenaco com fosfatidilcolina de soja e lipossomas unilamelares liofilizados

    Directory of Open Access Journals (Sweden)

    Luciana Biagini Lopes

    2006-12-01

    Full Text Available Phospholipids are widely used as structural amphiphilic compounds in liposome formulations. In this study, we have analyzed the interaction the sodium diclofenac (SD with soya phosphaditylcholine (PC and soya phosphatidylcholine from lyophilized small unilamellar liposomes (SUV. The changes in the properties of the co-lyophilized drug/PC from SUV liposomes, lyophilized PC from SUV liposomes, and lyophilized soya phosphatidylcholine, were studied by Differential Scanning Calorimetry (DSC. The DSC data showed that the previous organization of phospholipids molecules to form liposome affects intensely the thermal behavior of PC when compared to non-lipossomal PC. SD modified the thermal properties of PC from liposomes. It was verified that SD affects intensely the located group peaks in the regions of 120-140 ºC and in the higher temperature region of 240-260 ºC. The results of this work demonstrated that the presence of the drug modified the DSC behavior for both liposomal and non-liposomal PC and that these modifications can be easily monitored by DSC analysis.Fosfolipídios são freqüentemente usados como compostos anfifílicos estruturais em formulações de lipossomas. Neste estudo foi analisada a interação do diclofenaco sódico (SD com a fosfatidilcolina de soja liofilizada e a fosfatidilcolina de soja (PC obtida de lipossomas unilamelares pequenos liofilizados (SUV. As modificações nas propriedades da mistura fármaco/PC co-liofilizados a partir de SUV pré-formados, lipossomas de PC vazios e PC liofilizada foram estudadas por Calorimetria Diferencial de Varredura (DSC. Os resultados de DSC mostraram que a organização prévia das moléculas PC para formar lipossomas interfere significativamente no perfil de DSC da PC, quando comparada ao perfil de DSC da PC não-lipossômica. Verificou-se que o SD afeta intensamente o grupo de picos situados nas regiões de 120-140ºC e na região de mais alta temperatura (240-260ºC. Os resultados

  18. Use of Bacillus subtilis isolates from Tua-nao towards nutritional improvement of soya bean hull for monogastric feed application.

    Science.gov (United States)

    Wongputtisin, P; Khanongnuch, C; Kongbuntad, W; Niamsup, P; Lumyong, S; Sarkar, P K

    2014-09-01

    Soya bean hull (SBH) is a cheap and high-fibre content feed ingredient that obtained after soya bean oil extraction. Microbial fermentation was expected to improve SBH qualities before applying to animals, especially monogastric animals. Two bacterial strains, Bacillus subtilis MR10 and TK8 that were isolated from Tua-nao, a traditional fermented soya bean in northern Thailand, were used for fermented soya bean hull (FSBH) production. Both could easily grow at 37°C in SBH as the sole substrate. MR10 produced the highest β-mannanase activity (400 U g(-1) SBH) on day 2, while TK8 produced the highest cellulase activity (14·5 U g(-1) SBH) on day 3. After fermentation, the nutritional quality of SBH was obviously improved by an increase in soluble sugars, soluble proteins, crude protein and crude lipid, and a decrease in the content of raffinose family oligosaccharides. Scavenging activity (%) of SBH against ABTS radical cation was also increased from 14 to 27 and 20% by MR10 and TK8 fermentation, respectively. According to the GRAS property of these both strains and various improvements of nutritional values, the fermented SBH proved to be a potential feed ingredient, especially for the monogastric animals. Normally, soya bean hull has been recognized as only a worthless by-product from soya bean oil production process because of its low utilizable nutrients. Our study introduced an alternative way to utilize this worthless residue using biotechnological knowledge. The nutritional quality of soya bean hull was improved by microbial fermentation. Fermented soya bean hull can be used as a cheap, safe and high-nutrient feed ingredient for livestock production, especially monogastric animals, to promote their growth performances, instead of using antibiotics in some regions of the world. © 2014 The Society for Applied Microbiology.

  19. Use of γ-irradiation to produce films from whey, casein and soya proteins: structure and functionals characteristics

    International Nuclear Information System (INIS)

    Lacroix, M.; Le, T.C.; Ouattara, B.; Yu, H.; Letendre, M.; Sabato, S.F.; Mateescu, M.A.; Patterson, G.

    2002-01-01

    γ-irradiation and thermal treatments have been used to produce sterilized cross-linked films. Formulations containing variable concentrations of calcium caseinate and whey proteins (whey protein isolate (WPI) and commercial whey protein concentrate) or mixture of soya protein isolate (SPI) with WPI was investigated on the physico-chemical properties of these films. Results showed that the mechanical properties of cross-linked films improved significantly the puncture strength for all types of films. Size-exclusion chromatography showed for no cross-linked proteins, a molecular mass of around 40 kDa. The soluble fractions of the cross-linked proteins molecular distributions were between 600 and 3800 kDa. γ-irradiation seems to modify to a certain extent the conformation of proteins which will adopt structures more ordered and more stable, as suggested by X-ray diffraction analysis. Microstructure observations showed that the mechanical characteristics of these films are closely related to their microscopic structure. Water vapor permeability of films based on SPI was also significantly decreased when irradiated. Microbial resistance was also evaluated for cross-linked films. Results showed that the level of biodegradation of cross-linked films was 36% after 60 d of fermentation in the presence of Pseudomonas aeruginosa

  20. Enhanced thermal and mechanical properties of epoxy composites by mixing thermotropic liquid crystalline epoxy grafted graphene oxide

    Directory of Open Access Journals (Sweden)

    B. Qi

    2014-07-01

    Full Text Available Graphene oxide (GO sheets were chemically grafted with thermotropic liquid crystalline epoxy (TLCP. Then we fabricated composites using TLCP-g-GO as reinforcing filler. The mechanical properties and thermal properties of composites were systematically investigated. It is found that the thermal and mechanical properties of the composites are enhanced effectively by the addition of fillers. For instance, the composites containing 1.0 wt% of TLCP-g-GO present impact strength of 51.43 kJ/m2, the tensile strength of composites increase from 55.43 to 80.85 MPa, the flexural modulus of the composites increase by more than 48%. Furthermore, the incorporation of fillers is effective to improve the glass transition temperature and thermal stability of the composites. Therefore, the presence of the TLCP-g-GO in the epoxy matrix could make epoxy not only stronger but also tougher.

  1. A lumped model of venting during thermal runaway in a cylindrical lithium cobalt oxide lithium-ion cell

    DEFF Research Database (Denmark)

    Coman, Paul Tiberiu; Rayman, Sean; White, Ralph

    2016-01-01

    This paper presents a mathematical model built for analyzing the intricate thermal behavior of a 18650 LCO (Lithium Cobalt Oxide) battery cell during thermal runaway when venting of the electrolyte and contents of the jelly roll (ejecta) is considered. The model consists of different ODEs (Ordinary......, Christoph Stangl, Gisela Fauler, Gernot Voitice Alexander Thaler and Viktor Hacker, RSC Advances, 4:3633–3642, 2014] for two cases - with flow and without flow. The results show that if the isentropic flow equations are not included in the model, the thermal runaway is triggered prematurely at the point...... where venting should occur. This shows that the heat dissipation due to ejection of electrolyte and jelly roll contents has a significant contribution. When the flow equations are included, the model shows good agreement with the experiment and therefore proving the importance of including venting....

  2. Electro-optical characteristics of indium tin oxide (ITO) films: effect of thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, D.V.; Salehi, A.; Aliyu, Y.H.; Bunce, R.W. [University of Wales College of Cardiff (United Kingdom). School of Electrical, Electronics and System Engineering

    1996-02-01

    The effect of thermal annealing on the electrical and optical characteristics of ITO films prepared by reactive sputtering and thermal evaporation have been studied. The effect of the thermal annealing is to improve the conductivity and the optical transmission in the shorter wavelength region. The conductivity of the films increases with annealing temperature, this behaviour is associated with grain growth in the film. (author)

  3. Optimization of NO oxidation by H2O2 thermal decomposition at moderate temperatures.

    Science.gov (United States)

    Zhao, Hai-Qian; Wang, Zhong-Hua; Gao, Xing-Cun; Liu, Cheng-Hao; Qi, Han-Bing

    2018-01-01

    H2O2 was adopted to oxidize NO in simulated flue gas at 100-500°C. The effects of the H2O2 evaporation conditions, gas temperature, initial NO concentration, H2O2 concentration, and H2O2:NO molar ratio on the oxidation efficiency of NO were investigated. The reason for the narrow NO oxidation temperature range near 500°C was determined. The NO oxidation products were analyzed. The removal of NOx using NaOH solution at a moderate oxidation ratio was studied. It was proven that rapid evaporation of the H2O2 solution was critical to increase the NO oxidation efficiency and broaden the oxidation temperature range. the NO oxidation efficiency was above 50% at 300-500°C by contacting the outlet of the syringe needle and the stainless-steel gas pipe together to spread H2O2 solution into a thin film on the surface of the stainless-steel gas pipe, which greatly accelerated the evaporation of H2O2. The NO oxidation efficiency and the NO oxidation rate increased with increasing initial NO concentration. This method was more effective for the oxidation of NO at high concentrations. H2O2 solution with a concentration higher than 15% was more efficient in oxidizing NO. High temperatures decreased the influence of the H2O2 concentration on the NO oxidation efficiency. The oxidation efficiency of NO increased with an increase in the H2O2:NO molar ratio, but the ratio of H2O2 to oxidized NO decreased. Over 80% of the NO oxidation product was NO2, which indicated that the oxidation ratio of NO did not need to be very high. An 86.7% NO removal efficiency was obtained at an oxidation ratio of only 53.8% when combined with alkali absorption.

  4. Influence of thermal annealing on microstructural, morphological, optical properties and surface electronic structure of copper oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Akgul, Funda Aksoy, E-mail: fundaaksoy01@gmail.com [Department of Physics, Nigde University, 51240 Nigde (Turkey); Center for Solar Energy Research and Applications, Middle East Technical University, 06800 Ankara (Turkey); Akgul, Guvenc, E-mail: guvencakgul@gmail.com [Bor Vocational School, Nigde University, 51700 Nigde (Turkey); Center for Solar Energy Research and Applications, Middle East Technical University, 06800 Ankara (Turkey); Yildirim, Nurcan [Department of Physics Engineering, Ankara University, 06100 Ankara (Turkey); Department of Metallurgical and Materials Engineering, Middle East Technical University, 06800 Ankara (Turkey); Unalan, Husnu Emrah [Department of Metallurgical and Materials Engineering, Middle East Technical University, 06800 Ankara (Turkey); Center for Solar Energy Research and Applications, Middle East Technical University, 06800 Ankara (Turkey); Turan, Rasit [Department of Physics, Middle East Technical University, 06800 Ankara (Turkey); Center for Solar Energy Research and Applications, Middle East Technical University, 06800 Ankara (Turkey)

    2014-10-15

    In this study, effect of the post-deposition thermal annealing on copper oxide thin films has been systemically investigated. The copper oxide thin films were chemically deposited on glass substrates by spin-coating. Samples were annealed in air at atmospheric pressure and at different temperatures ranging from 200 to 600°C. The microstructural, morphological, optical properties and surface electronic structure of the thin films have been studied by diagnostic techniques such as X-ray diffraction (XRD), Raman spectroscopy, ultraviolet–visible (UV–VIS) absorption spectroscopy, field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The thickness of the films was about 520 nm. Crystallinity and grain size was found to improve with annealing temperature. The optical bandgap of the samples was found to be in between 1.93 and 2.08 eV. Cupric oxide (CuO), cuprous oxide (Cu{sub 2}O) and copper hydroxide (Cu(OH){sub 2}) phases were observed on the surface of as-deposited and 600 °C annealed thin films and relative concentrations of these three phases were found to depend on annealing temperature. A complete characterization reported herein allowed us to better understand the surface properties of copper oxide thin films which could then be used as active layers in optoelectronic devices such as solar cells and photodetectors. - Highlights: • Effect of post-deposition annealing on copper oxide thin films was investigated. • Structural, optical, and electronic properties of the thin films were determined. • Oxidation states of copper oxide thin films were confirmed by XPS analysis. • Mixed phases of CuO and Cu{sub 2}O were found to coexist in copper oxide thin films.

  5. Engineering soya bean seeds as a scalable platform to produce cyanovirin-N, a non-ARV microbicide against HIV.

    Science.gov (United States)

    O'Keefe, Barry R; Murad, André M; Vianna, Giovanni R; Ramessar, Koreen; Saucedo, Carrie J; Wilson, Jennifer; Buckheit, Karen W; da Cunha, Nicolau B; Araújo, Ana Claudia G; Lacorte, Cristiano C; Madeira, Luisa; McMahon, James B; Rech, Elibio L

    2015-09-01

    There is an urgent need to provide effective anti-HIV microbicides to resource-poor areas worldwide. Some of the most promising microbicide candidates are biotherapeutics targeting viral entry. To provide biotherapeutics to poorer areas, it is vital to reduce the cost. Here, we report the production of biologically active recombinant cyanovirin-N (rCV-N), an antiviral protein, in genetically engineered soya bean seeds. Pure, biologically active rCV-N was isolated with a yield of 350 μg/g of dry seed weight. The observed amino acid sequence of rCV-N matched the expected sequence of native CV-N, as did the mass of rCV-N (11 009 Da). Purified rCV-N from soya is active in anti-HIV assays with an EC50 of 0.82-2.7 nM (compared to 0.45-1.8 nM for E. coli-produced CV-N). Standard industrial processing of soya bean seeds to harvest soya bean oil does not diminish the antiviral activity of recovered rCV-N, allowing the use of industrial soya bean processing to generate both soya bean oil and a recombinant protein for anti-HIV microbicide development. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  6. Solid state fermentation with lactic acid bacteria to improve the nutritional quality of lupin and soya bean.

    Science.gov (United States)

    Bartkiene, Elena; Krungleviciute, Vita; Juodeikiene, Grazina; Vidmantiene, Daiva; Maknickiene, Zita

    2015-04-01

    The ability of bacteriocin-like inhibitory substance (BLIS)-producing lactic acid bacteria (LAB) to degrade biogenic amines as well as to produce L(+) and D(-)-lactic acid during solid state fermentation (SSF) of lupin and soya bean was investigated. In addition, the protein digestibility and formation of organic acids during SSF of legume were investigated. Protein digestibility of fermented lupin and soya bean was found higher on average by 18.3% and 15.9%, respectively, compared to untreated samples. Tested LAB produced mainly L-lactic acid in soya bean and lupin (D/L ratio 0.38-0.42 and 0.35-0.54, respectively), while spontaneous fermentation gave almost equal amounts of both lactic acid isomers (D/L ratio 0.82-0.98 and 0.92, respectively). Tested LAB strains were able to degrade phenylethylamine, spermine and spermidine, whereas they were able to produce putrescine, histamine and tyramine. SSF improved lupin and soya bean protein digestibility. BLIS-producing LAB in lupin and soya bean medium produced a mixture of D- and L-lactic acid with a major excess of the latter isomer. Most toxic histamine and tyramine in fermented lupin and soya bean were found at levels lower those causing adverse health effects. Selection of biogenic amines non-producing bacteria is essential in the food industry to avoid the risk of amine formation. © 2014 Society of Chemical Industry.

  7. Strength and thermal stability of Cu-Al2O3 composite obtained by internal oxidation

    Directory of Open Access Journals (Sweden)

    Jovanovic, M. T.

    2010-12-01

    Full Text Available The objective of the work is to study the effects of the high-energy milling on strengthening, thermal stability and electrical conductivity of Cu-Al2O3 composite. The prealloyed copper powders, atomized in inert gas and containing 3 wt. % Al, were milled up to 20 h in the planetary ball mill to oxidize in situ aluminium with oxygen from the air. Composite compacts were obtained by hot-pressing in an argon atmosphere at 800 °C for 3 h under the pressure of 35MPa. The microstructural characterization was performed by the optical microscope, scanning electron microscope (SEM, transmission electron microscope (TEM and X-ray diffraction analysis (XRD. The microhardness, electrical conductivity and density measurements were also carried out. The effect of internal oxidation and high-energy milling on strengthening of Cu-Al2O3 composite was significant, The increase of the microhardness of composite compacts (292 HV is almost threefold comparing to compacts processed from the as-received Cu-3 wt. % Al powder (102 HV. The grain size of Cu-Al2O3 compacts processed from 5 and 20 h-milled powders was 75 and 45 nm, respectively. The small increase in the grain size and the small microhardness drop indicate the high thermal stability of Cu-Al2O3 composite during high-temperature exposure at 800 °C.El objetivo del trabajo es el estudio de los efectos de la pulverización con altas energías sobre la resistencia, estabilidad térmica y conductividad eléctrica del compuesto Cu-Al2O3. El polvo pre-aleado de cobre, obtenido a través de la atomización con gas inerte y con un contenido de 3wt. % Al, se molió durante 20 h en el molino planetario de bolas dando lugar a la oxidación in situ del aluminio con el oxígeno del aire. El compuesto compactado se ha obtenido mediante prensado en caliente en atmósfera de argón a 800 °C durante 3 h y a una presión de 35MPa. La caracterización microestructural se hizo a través de microscopia óptica, microscopia

  8. Thermal conductivity and tensile properties of tin oxide filled UPR/EPS composites with and without organic nanocrystal

    Science.gov (United States)

    Mohamed, R.; Syed Mustafa, S. A.; Norizan, Mohd N.; Suraya Amerudin, L.

    2017-07-01

    Panel composite for building application made from waste expanded polystyrene (EPS) and unsaturated polyester (UPR) were fabricated and tested in this research for their tensile and thermal characteristics in determining its insulation properties. Research had been carried out to incorporate EPS into UPR with addition of two additives types which are tin oxide (SnO) stand alone, and tin oxide in combination with organic nanocrystals. The weight percentage of SnO had been varied from 0.1 to 2%, and the nanocrystals between 0.1 to 0.5%; both fabricated via casting and compression of the UPR/EPS composite. The testing performed are tensile properties by an Instron Universal Tensile Machine; and thermal conductivity test by using KD2 Pro hand-held thermal probe. It was found that, by using UPE/EPS, the additives affected the composites' thermal conductivity and tensile capabilities. For tensile strength, the control sample showed the highest tensile strength at 22.2 MPa. For thermal conductivity (k value), the lowest value was recorded by the 1% SnO stand alone at an approximate ~ 0.172 W/m.K. Via organic nanocrystal use fixed at 0.1%, the k value increases up to a certain point with increasing SnO. Addition of more SnO and nanocrystal incorporation had mostly increases its thermal conductivity and heat capacity. Heat capacity was also found to be at the lowest in the 1% SnO stand alone sample at 2.008 MJ/m3.K.

  9. Aerial and liquid effluent treatment in BNFL's Thermal Oxide Reprocessing Plant (THORP)

    International Nuclear Information System (INIS)

    Hudson, P.I.; Buckley, C.P.

    1996-01-01

    British Nuclear Fuels plc (BNFL) completed construction of its Thermal Oxide Reprocessing Plant (THORP) at Sellafield in 1992, at a cost of pound 1,850M. After Government and Regulatory approval, active commissioning was initiated in January 1994. Since then, the whole of the plant has been progressively commissioned and moved towards full operational status. From the outset, the need to protect the workforce, the public and the environment in general from the plant's discharges was clearly recognised. The design intent was to limit radiation exposure of members of the general public to 'As Low as Reasonably Practicable' (ALARP). Furthermore no member of the most highly exposed (critical) group should receive an annual dose exceeding 50 microsieverts from either the aerial or marine discharge routes. This paper describes how the design intent has been met, concentrating mainly on aerial discharges. It describes the sub-division of the plant's ventilation system into a number of separate systems, according to the volume and source of the arising and the complexity of the treatment process. The dissolver off-gas, central off-gas, cell and building ventilation systems are described, together with the development programme which was undertaken to address the more demanding aspects of the performance specification. This ranged from small-scale experiments with irradiated fuel to inactive pilot plant trials and full-scale plant measurements. In addition wind tunnel tests were employed to assist dispersion modelling of the gases as they are discharged from the THORP stack. All the resulting information was then used, with the aid of mathematical models, in the design of an off-gas treatment system which could achieve the overall goal. (J.P.N.)

  10. Growth of High-Density Zinc Oxide Nanorods on Porous Silicon by Thermal Evaporation

    Directory of Open Access Journals (Sweden)

    Nurul Izni Rusli

    2012-12-01

    Full Text Available The formation of high-density zinc oxide (ZnO nanorods on porous silicon (PS substrates at growth temperatures of 600–1000 °C by a simple thermal evaporation of zinc (Zn powder in the presence of oxygen (O2 gas was systematically investigated. The high-density growth of ZnO nanorods with (0002 orientation over a large area was attributed to the rough surface of PS, which provides appropriate planes to promote deposition of Zn or ZnOx seeds as nucleation sites for the subsequent growth of ZnO nanorods. The geometrical morphologies of ZnO nanorods are determined by the ZnOx seed structures, i.e., cluster or layer structures. The flower-like hexagonal-faceted ZnO nanorods grown at 600 °C seem to be generated from the sparsely distributed ZnOx nanoclusters. Vertically aligned hexagonal-faceted ZnO nanorods grown at 800 °C may be inferred from the formation of dense arrays of ZnOx clusters. The formation of disordered ZnO nanorods formed at 1000 °C may due to the formation of a ZnOx seed layer. The growth mechanism involved has been described by a combination of self-catalyzed vapor-liquid-solid (VLS and vapor-solid (VS mechanism. The results suggest that for a more precise study on the growth of ZnO nanostructures involving the introduction of seeds, the initial seed structures must be taken into account given their significant effects.

  11. On the use of thermal NF3 as the fluorination and oxidation agent in treatment of used nuclear fuels

    Science.gov (United States)

    Scheele, Randall; McNamara, Bruce; Casella, Andrew M.; Kozelisky, Anne

    2012-05-01

    This paper presents results of our investigation on the use of nitrogen trifluoride as a fluorination or fluorination/oxidation agent for separating valuable constituents from used nuclear fuels by exploiting the different volatilities of the constituent fission product and actinide fluorides. Our thermodynamic calculations show that nitrogen trifluoride has the potential to produce volatile fission product and actinide fluorides from oxides and metals that can form volatile fluorides. Simultaneous thermogravimetric and differential thermal analyses show that the oxides of lanthanum, cerium, rhodium, and plutonium are fluorinated but do not form volatile fluorides when treated with nitrogen trifluoride at temperatures up to 550 °C. However, depending on temperature, volatile fluorides or oxyfluorides can form from nitrogen trifluoride treatment of the oxides of niobium, molybdenum, ruthenium, tellurium, uranium, and neptunium. Thermoanalytical studies demonstrate near-quantitative separation of uranium from plutonium in a mixed 80% uranium and 20% plutonium oxide. Our studies of neat oxides and metals suggest that the reactivity of nitrogen trifluoride may be adjusted by temperature to selectively separate the major volatile fuel constituent uranium from minor volatile constituents, such as Mo, Tc, Ru and from the non-volatile fuel constituents based on differences in their reaction temperatures and kinetic behaviors. This reactivity is novel with respect to that reported for other fluorinating reagents F2, BrF5, ClF3.

  12. Thermal Methane Conversion to Syngas Mediated by Rh1-Doped Aluminum Oxide Cluster Cations RhAl3O4.

    Science.gov (United States)

    Li, Ya-Ke; Yuan, Zhen; Zhao, Yan-Xia; Zhao, Chongyang; Liu, Qing-Yu; Chen, Hui; He, Sheng-Gui

    2016-10-05

    Laser ablation generated RhAl 3 O 4 + heteronuclear metal oxide cluster cations have been mass-selected using a quadrupole mass filter and reacted with CH 4 or CD 4 in a linear ion trap reactor under thermal collision conditions. The reactions have been characterized by state-of-the-art mass spectrometry and quantum chemistry calculations. The RhAl 3 O 4 + cluster can activate four C-H bonds of a methane molecule and convert methane to syngas, an important intermediate product in methane conversion to value-added chemicals. The Rh atom is the active site for activation of the C-H bonds of methane. The high electron-withdrawing capability of Rh atom is the driving force to promote the conversion of methane to syngas. The polarity of Rh oxidation state is changed from positive to negative after the reaction. This study has provided the first example of methane conversion to syngas by heteronuclear metal oxide clusters under thermal collision conditions. Furthermore, the molecular level origin has been revealed for the condensed-phase experimental observation that trace amounts of Rh can promote the participation of lattice oxygen of chemically very inert support (Al 2 O 3 ) to oxidize methane to carbon monoxide.

  13. Sulfur-doped graphene via thermal exfoliation of graphite oxide in H2S, SO2, or CS2 gas.

    Science.gov (United States)

    Poh, Hwee Ling; Šimek, Petr; Sofer, Zdeněk; Pumera, Martin

    2013-06-25

    Doping of graphene with heteroatoms is an effective way to tailor its properties. Here we describe a simple and scalable method of doping graphene lattice with sulfur atoms during the thermal exfoliation process of graphite oxides. The graphite oxides were first prepared by Staudenmaier, Hofmann, and Hummers methods followed by treatments in hydrogen sulfide, sulfur dioxide, or carbon disulfide. The doped materials were characterized by scanning electron microscopy, high-resolution X-ray photoelectron spectroscopy, combustible elemental analysis, and Raman spectroscopy. The ζ-potential and conductivity of sulfur-doped graphenes were also investigated in this paper. It was found that the level of doping is more dramatically influenced by the type of graphite oxide used rather than the type of sulfur-containing gas used during exfoliation. Resulting sulfur-doped graphenes act as metal-free electrocatalysts for an oxygen reduction reaction.

  14. Influence of experimental parameters on iron oxide nanoparticle properties synthesized by thermal decomposition: size and nuclear magnetic resonance studies

    Science.gov (United States)

    Belaïd, Sarah; Stanicki, Dimitri; Vander Elst, Luce; Muller, Robert N.; Laurent, Sophie

    2018-04-01

    A study of the experimental conditions to synthesize monodisperse iron oxide nanocrystals prepared from the thermal decomposition of iron(III) acetylacetonate was carried out in the presence of surfactants and a reducing agent. The influence of temperature, synthesis time and surfactant amounts on nanoparticle properties is reported. This investigation combines relaxometric characterization and size properties. The relaxometric behavior of the nanomaterials depends on the selected experimental parameters. The synthesis of iron oxide nanoparticles with a high relaxivity and a high saturation magnetization can be obtained with a short reaction time at high temperature. Moreover, the influence of surfactant concentrations determines the optimal value in order to produce iron oxide nanoparticles with a narrow size distribution. The optimized synthesis is rapid, robust and reproductive, and produces nearly monodisperse magnetic nanocrystals.

  15. 40 CFR 721.10055 - 1-Propanaminium, 3-amino-N-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts.

    Science.gov (United States)

    2010-07-01

    ...-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts. 721.10055 Section 721.10055 Protection of...-amino-N-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts. (a) Chemical substance and...-(carboxymethyl)-N,N-dimethyl-, N-soya acyl derivs., inner salts (PMN P-03-46; CAS No. 136504-87-5) is subject to...

  16. Preparation of Graphene Oxide Stabilized Nickel Nanoparticles with Thermal Effusivity Properties by Laser Ablation Method

    OpenAIRE

    Sadrolhosseini, Amir Reza; Noor, A. S. M.; Shameli, Kamyar; Kharazmi, Alireza; Huang, N. M.; Mahdi, M. A.

    2013-01-01

    Nickel nanoparticles were dispersed uniformly in a graphene oxide solution, using a laser ablation technique with different ablation times that ranged from 5 to 20 minutes. The results indicate that the nickel nanoparticle sizes inside the graphene oxide decreased, and the volume fraction for the nickel nanoparticles in the graphene oxide increased with an increasing ablation time. Further, using Fourier Transform Infrared Spectroscopy, the nickel nanoparticles in the graphene oxide demonstra...

  17. Method for improving catalyst function in auto-thermal and partial oxidation reformer-based processors

    Science.gov (United States)

    Ahmed, Shabbir; Papadias, Dionissios D.; Lee, Sheldon H.D.; Ahluwalia, Rajesh K.

    2014-08-26

    The invention provides a method for reforming fuel, the method comprising contacting the fuel to an oxidation catalyst so as to partially oxidize the fuel and generate heat; warming incoming fuel with the heat while simultaneously warming a reforming catalyst with the heat; and reacting the partially oxidized fuel with steam using the reforming catalyst.

  18. Isoflavones from soya foods are more bioavailable in children than adults.

    Science.gov (United States)

    Halm, Brunhild M; Ashburn, Leslie A; Franke, Adrian A

    2007-11-01

    The purpose of the present study was to determine whether children experience a higher systemic exposure to isoflavonoids when consuming a body weight-adjusted dose of soya compared with adults. Forty study participants were recruited from a local Waldorf school, including twenty-one children and nineteen adults. Participants collected a baseline urine sample and ate immediately thereafter a body weight-adjusted dose of soya nuts (15 g/54.4 kg equivalent to 0.615 (SD 0.036) mg total isoflavones/kg) followed by a 12 h urine collection. Nineteen children and eighteen adults completed the protocol correctly (fourteen child-parent pairs). Children, compared with adults, showed a statistically significant (P bioavailable in children v. adults. Urine is an excellent medium to determine systemic isoflavone exposure in children due to its non-invasiveness and high compliance, in particular when collected overnight; it also allows evaluation of completeness of specimen collection.

  19. Estudio del contenido de ácidos grasos superiores en veinte variedades tropicales de soya

    Directory of Open Access Journals (Sweden)

    Boris Kocelj Ramírez

    2009-05-01

    Full Text Available Muy poco se sabe acerca del contenido de ácidos grasos en las diferentes variedades tropicales de soya. En este trabajo se estudiaron veinte variedades tropicales de soya en lo referente a su contenido de aceite y en ácidos grasos. Se determinaros las propiedades físicas y químicas del aceite que lo caracteizan como comestible. El contenido cualitativo y cuantitativo de ácidos grasos individuales se investigó utilizando la técnica de cromatografía de gases. Se analizaron los éteres correspondientes, obtenidos por esterificación catalítica completa con trifluoruro de Boro-metanol. Se encontraron diferencias significativas entre las propiedades de los aceites de las variedades estudiadas. Se identificaron los ácidos: palmítico, esteárico, linoleico y linolénico

  20. Estudio de Factibilidad para la creación de una empresa productora y comercializadora de leche de Soya en el Sectro Norte de Quito

    OpenAIRE

    Andrango Logacho, Geovanna Inés

    2009-01-01

    La semilla de soya ha formado parte de la dieta de los seres humanos por casi 5.000 años y a diferencia de la mayoría de los alimentos provenientes de las plantas, la semilla de soya es rica en proteínas y se considera equivalente a los alimentos provenientes de animales en términos de calidad de la proteína que la soya contiene. La soya es un cultivo con efectos beneficiosos para los suelos, es una oleaginosa de alto valor nutritivo y de múltiples usos en el procesamiento ...

  1. Diseño de proceso para el desarrollo de barras energéticas como subproducto en la obtención de leche saborizada de soya

    OpenAIRE

    Gamboa Valarezo, Vannia; Costa, Ana Maria

    2009-01-01

    El grano de soya es ampliamente reconocido por su elevado contenido en nutrientes. Durante el proceso de elaboración de la leche de soya el okara o pulpa residual del proceso representó del 20 a 25 por ciento del desperdicio cuyo alto valor nutricional y energético fue aprovechado. En el presente trabajo se propuso aprovechar integralmente el grano de soya, dando valor agregado a la fase líquida donde se obtuvo leche saborizada de soya y, a partir del desperdicio se obtuvieron barras ene...

  2. Scientists Grow Therapeutic Protein in Engineered Soya Bean Seeds to Prevent AIDS | Poster

    Science.gov (United States)

    Genetically modified soya beans provide a scalable, low-cost method of producing microbicides that prevent AIDS, a technique sustainable for resource-poor countries where AIDS is spreading rapidly. According to the Joint United Nations Programme on HIV/AIDS, more than 36 million people worldwide are living with HIV. While the number of AIDS-related deaths are decreasing, infection rates are still increasing, specifically in Eastern and Southern Africa.

  3. Thermal conductivity evaluation of high burnup mixed-oxide (MOX) fuel pellet

    Science.gov (United States)

    Amaya, Masaki; Nakamura, Jinichi; Nagase, Fumihisa; Fuketa, Toyoshi

    2011-07-01

    The thermal conductivity formula of fuel pellet which contains the effects of burnup and plutonium (Pu) addition was proposed based on the Klemens' theory and reported thermal conductivities of unirradiated (U, Pu) O 2 and irradiated UO 2 pellets. The thermal conductivity of high burnup MOX pellet was formulated by applying a summation rule between phonon scattering parameters which show the effects of plutonium addition and burnup. Temperature of high burnup MOX fuel was evaluated based on the thermal conductivity integral which was calculated from the above-mentioned thermal conductivity formula. Calculated fuel temperatures were plotted against the linear heat rates of the fuel rods, and were compared with the fuel temperatures measured in a test reactor. Since both values agreed well, it was confirmed that the proposed thermal conductivity formula of MOX pellets is adequate.

  4. Safety assessment of the biogenic amines in fermented soya beans and fermented bean curd.

    Science.gov (United States)

    Yang, Juan; Ding, Xiaowen; Qin, Yingrui; Zeng, Yitao

    2014-08-06

    To evaluate the safety of biogenic amines, high performance liquid chromatography (HPLC) was used to evaluate the levels of biogenic amines in fermented soya beans and fermented bean curd. In fermented soya beans, the total biogenic amines content was in a relatively safe range in many samples, although the concentration of histamine, tyramine, and β-phenethylamine was high enough in some samples to cause a possible safety threat, and 8 of the 30 samples were deemed unsafe. In fermented bean curd, the total biogenic amines content was more than 900 mg/kg in 19 white sufu amples, a level that has been determined to pose a safety hazard; putrescine was the only one detected in all samples and also had the highest concentration, which made samples a safety hazard; the content of tryptamine, β-phenethylamine, tyramine, and histamine had reached the level of threat to human health in some white and green sufu samples, and that may imply another potential safety risk; and 25 of the 33 samples were unsafe. In conclusion, the content of biogenic amines in all fermented soya bean products should be studied and appropriate limits determined to ensure the safety of eating these foods.

  5. Fermente bir Soya Ürünü “Miso”

    Directory of Open Access Journals (Sweden)

    Kamuran Ayhan

    2015-02-01

    Full Text Available Miso, Uzakdoğu’da üretilen ve insanlarca fazla miktarda tüketilen fermente bir soya ürünüdür. Miso üretiminde hammadde olarak soya fasulyesi, pirinç veya arpa, tuz ve mikroorganizma kültürü (Aspergillus oryzae kullanılmaktadır. Miso’nun rengi koyu kahverenginden açık sarıya kadar değişim göstermektedir. Fermentasyon sırasında soya fasulyesinde bulunan protein, karbonhidrat ve yağlar daha basit bileşim unsurlarına parçalanmaktadır. Miso, %12.5-19.0 protein, %1.4-6.9 yağ, %5.5-13 oranında tuz içermekte, lezzet verici bir gıda maddesi özelliği taşımaktadır. Miso özellikle esansiyel amino asitlerce zengindir. Protein kalitesini belirleyen NPU (Net protein kullanımı değeri misoda %72’dir. Protein kalitesi açısından bilinen protein kaynaklı gıdalar içinde ilk sırayı almaktadır.

  6. [Determination of total protein content in soya-bean milk via visual moving reaction boundary titration].

    Science.gov (United States)

    Guo, Chengye; Wang, Houyu; Zhang, Lei; Fan, Liuyin; Cao, Chengxi

    2013-11-01

    A visual, rapid and accurate moving reaction boundary titration (MRBT) method was used for the determination of the total protein in soya-bean milk. During the process, moving reaction boundary (MRB) was formed by hydroxyl ions in the catholyte and soya-bean milk proteins immobilized in polyacrylamide gel (PAG), and an acid-base indicator was used to denote the boundary motion. The velocity of MRB has a relationship with protein concentration, which was used to obtain a standard curve. By paired t-test, there was no significant difference of the protein content between MRBT and Kjeldahl method at 95% confidence interval. The procedure of MRBT method required about 10 min, and it had linearity in the range of 2.0-14.0 g/L, low limit of detection (0.05 g/L), good precision (RSD of intra-day < 1.90% and inter-day < 4.39%), and high recoveries (97.41%-99.91%). In addition, non-protein nitrogen (NPN) such as melamine added into the soya-bean milk had weak influence on MRBT results.

  7. Influence of bitter lupin on consumption and digestibility in organic dairy cattle soya bean free diets

    Directory of Open Access Journals (Sweden)

    R. Tocci

    2010-04-01

    Full Text Available One of the main principles of organic husbandry is that animal feed must be GMO free, and soya bean is well-known as a high risk GMO alimentary source. About 25 dry dairy cattle of the Italian Holstein breed, from the Cooperativa Emilio Sereni of Borgo S. Lorenzo (FI, were fed in two successive diets: the first with extruded soya bean (A, and the second in which bitter lupin, faba bean and proteinic pea substituted the soya bean (B. We evaluated both the consumption and the apparent digestibility (using acid insoluble ash as internal marker of the two diets, repeating the trial twice. The presence of bitter lupin did not influence either the consumption of other feed, or the faecal water content. The apparent digestibility of the organic matter resulted satisfactory in both the diets, but was significantly higher in diet (A than in diet (B (71,6% vs 67,3%. In conclusion, even though we wish the cultivation of sweet lupin would be increase in Italy, we retain that also bitter lupin (mixed with other feed to increase the palatability could be used as alternative protein source in dairy cattle diets.

  8. Isoflavones from green vegetable soya beans and their antimicrobial and antioxidant activities.

    Science.gov (United States)

    Wang, Taoyun; Liu, Yanli; Li, Xiaoran; Xu, Qiongming; Feng, Yulin; Yang, Shilin

    2018-03-01

    Green vegetable soya beans, known as Maodou in China, are supplied as vegetable-type fruits of the soybean plant. Previous study indicated that green vegetable soya beans exhibited antioxidative and anti-inflammatory activities. However, the material basis and pharmacological activities of green soybean plant were not unravelled clearly. In this study, we investigated the chemical ingredients and their pharmacological activities. Investigation of the chemical ingredients indicated that two new isoflavones, 2'-hydroxyerythrin A (1), and daidzein-7-O-β-d-{6″-[(E)-but-2-enoyl]}glycoside (2), together with seven known ones - 7,4'-dihydroxy-6-methoxyisoflavone (3), daidzein (4), daidzin (5), genistein (6), formononetin (7), ononin (8), and isoerythrinin A (9) - were obtained. The structures of compounds 1-9 were elucidated on the basis of spectroscopic and chemical analysis. We evaluated the antimicrobial efficacies and free-radical scavenging potential of the isolated compounds (1-9). Compounds 1 and 9 exhibited the most pronounced efficacy against the tested bacterial strains with IC 50 values ranging from 10.6 to 22.6 μg mL -1 . The isolated compounds showed moderate radical scavenging properties with compound 6 being the most active, followed by compounds 3, 1 and 4. This study indicated that the isoflavones from soya beans could be considered as potential antioxidants or antimicrobials in the food, cosmetics and pharmaceutical industries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  9. Room-temperature cataluminescence from CO oxidation in a non-thermal plasma-assisted catalysis system.

    Science.gov (United States)

    Han, Feifei; Yang, Yuhan; Han, Jiaying; Ouyang, Jin; Na, Na

    2015-08-15

    Cataluminescence (CTL) is a kind of chemiluminescence during catalytic reaction on surface of catalysts under a heated condition. Due to the low catalytic reactivity of CO, normally low intensity of CTL is obtained during heterogeneously catalytic oxidation of CO under heated conditions (normally higher than 150°C), even catalyzed by precious-metal-based catalysts. Therefore, seeking enhanced CTL of CO at room temperature and using low-cost catalysts becomes significant. Here, CTL generated from CO oxidation was firstly reported at room temperature, which was carried out in a non-thermal plasma-assisted (NTPA) catalysis system. With air acting as discharge gas, carrier gas as well as oxidant, a Mn/SiO2 nanomaterials-based NTPA catalysis system was fabricated for CO catalytic oxidation at room temperature, whose temperature was much lower than previous CTL methods. Relatively high and selective CTL responses were acquired during CO oxidation on surface of Mn/SiO2 nanomaterials, whereas no significant CTL signal was recorded without plasma assistance or on other metals-doped SiO2 catalysts. Without any excitation light source or heating element, a low cost and simple CO sensor was fabricated by using common and easily synthesized catalysts. The present work has greatly simplified the constructions, and enlarged CTL applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Effect of alkali and oxidative treatments on the physicochemical, pasting, thermal and morphological properties of corn starch.

    Science.gov (United States)

    Spier, Franciela; Zavareze, Elessandra da Rosa; Marques e Silva, Ricardo; Elias, Moacir Cardoso; Dias, Alvaro Renato Guerra

    2013-07-01

    Few studies on starch modifications using different chemical agents are available in the literature, and no reports were found on the combined effect of oxidation and alkaline treatment of corn starch. Thus this work evaluated the physicochemical, pasting, morphological, cystallinity and thermal properties of chemically modified corn starch, after either the isolated or combined action of alkaline (sodium hydroxide) and oxidative (sodium hypochlorite) treatments. The highest values for the sum of carbonyl and carboxyl and enzymatic hydrolysis occurred in starches submitted to oxidative treatment at high active chlorine concentrations. The alkali treatment in isolation modified the pasting properties, reduced the paste temperature and increased the peak viscosity, breakdown, final viscosity and setback of starches. Starch modified by the action of sodium hypochlorite and hydroxide in combination presented more severe damage on granule surfaces. The results show that corn starch modified by the combined action of oxidative and alkaline treatments should be studied more, especially at the concentration limit of sodium hydroxide where gelatinization occurs. Under these conditions the effect of oxidation can be more intense and thus allow the production of starches with different properties and an increase in their industrial applications. © 2013 Society of Chemical Industry.

  11. Mechanisms Underpinning Degradation of Protective Oxides and Thermal Barrier Coatings in High Hydrogen Content (HHC) - Fueled Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Mumm, Daniel

    2013-08-31

    The overarching goal of this research program has been to evaluate the potential impacts of coal-derived syngas and high-hydrogen content fuels on the degradation of turbine hot-section components through attack of protective oxides and thermal barrier coatings. The primary focus of this research program has been to explore mechanisms underpinning the observed degradation processes, and connections to the combustion environments and characteristic non-combustible constituents. Based on the mechanistic understanding of how these emerging fuel streams affect materials degradation, the ultimate goal of the program is to advance the goals of the Advanced Turbine Program by developing materials design protocols leading to turbine hot-section components with improved resistance to service lifetime degradation under advanced fuels exposures. This research program has been focused on studying how: (1) differing combustion environments – relative to traditional natural gas fired systems – affect both the growth rate of thermally grown oxide (TGO) layers and the stability of these oxides and of protective thermal barrier coatings (TBCs); and (2) how low levels of fuel impurities and characteristic non-combustibles interact with surface oxides, for instance through the development of molten deposits that lead to hot corrosion of protective TBC coatings. The overall program has been comprised of six inter-related themes, each comprising a research thrust over the program period, including: (i) evaluating the role of syngas and high hydrogen content (HHC) combustion environments in modifying component surface temperatures, heat transfer to the TBC coatings, and thermal gradients within these coatings; (ii) understanding the instability of TBC coatings in the syngas and high hydrogen environment with regards to decomposition, phase changes and sintering; (iii) characterizing ash deposition, molten phase development and infiltration, and associated corrosive

  12. Beryllium Project: developing in CDTN of uranium dioxide fuel pellets with addition of beryllium oxide to increase the thermal conductivity

    International Nuclear Information System (INIS)

    Ferreira, Ricardo Alberto Neto; Camarano, Denise das Merces; Miranda, Odair; Grossi, Pablo Andrade; Andrade, Antonio Santos; Queiroz, Carolinne Mol; Gonzaga, Mariana de Carvalho Leal

    2013-01-01

    Although the nuclear fuel currently based on pellets of uranium dioxide be very safe and stable, the biggest problem is that this material is not a good conductor of heat. This results in an elevated temperature gradient between the center and its lateral surface, which leads to a premature degradation of the fuel, which restricts the performance of the reactor, being necessary to change the fuel before its full utilization. An increase of only 5 to 10 percent in its thermal conductivity, would be a significant increase. An increase of 50 percent would be a great improvement. A project entitled 'Beryllium Project' was developed in CDTN - Centro de Desenvolvimento da Tecnologia Nuclear, which aimed to develop fuel pellets made from a mixture of uranium dioxide microspheres and beryllium oxide powder to obtain a better heat conductor phase, filling the voids between the microspheres to increase the thermal conductivity of the pellet. Increases in the thermal conductivity in the range of 8.6% to 125%, depending on the level of addition employed in the range of 1% to 14% by weight of beryllium oxide, were obtained. This type of fuel promises to be safer than current fuels, improving the performance of the reactor, in addition to last longer, resulting in great savings. (author)

  13. Runaway behavior and thermally safe operation of multiple liquid-liquid reactions in the semi-batch reactor. The nitric acid oxidation of 2-octanol.

    NARCIS (Netherlands)

    van Woezik, B.A.A.; Westerterp, K.R.

    2001-01-01

    The thermal runaway behavior of an exothermic, heterogeneous, multiple reaction system has been studied in a cooled semi-batch reactor. The nitric acid oxidation of 2-octanol has been used to this end. During this reaction, 2-octanone is formed, which can be further oxidized to unwanted carboxylic

  14. Thermal Degradation Kinetics Modeling of Benzophenones and Xanthones during High-Temperature Oxidation of Cyclopia genistoides (L.) Vent. Plant Material.

    Science.gov (United States)

    Beelders, Theresa; de Beer, Dalene; Joubert, Elizabeth

    2015-06-10

    Degradation of the major benzophenones, iriflophenone-3-C-glucoside-4-O-glucoside and iriflophenone-3-C-glucoside, and the major xanthones, mangiferin and isomangiferin, of Cyclopia genistoides followed first-order reaction kinetics during high-temperature oxidation of the plant material at 80 and 90 °C. Iriflophenone-3-C-glucoside-4-O-glucoside was shown to be the most thermally stable compound. Isomangiferin was the second most stable compound at 80 °C, while its degradation rate constant was influenced the most by increased temperature. Mangiferin and iriflophenone-3-C-glucoside had comparable degradation rate constants at 80 °C. The thermal degradation kinetic model was subsequently evaluated by subjecting different batches of plant material to oxidative conditions (90 °C/16 h). The model accurately predicted the individual contents of three of the compounds in aqueous extracts prepared from oxidized plant material. The impact of benzophenone and xanthone degradation was reflected in the decreased total antioxidant capacity of the aqueous extracts, as determined using the oxygen radical absorbance capacity and DPPH(•) scavenging assays.

  15. Exchange bias coupling in NiO/Ni bilayer tubular nanostructures synthetized by electrodeposition and thermal oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, T., E-mail: work_tian@scu.edu.cn [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Zhang, Z.W.; Xu, Y.H. [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Liu, Y. [Analytical & Testing Center, Sichuan University, Chengdu 610064 (China); Li, W.J. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190 (China); Nie, Y.; Zhang, X. [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Xiang, G., E-mail: gxiang@scu.edu.cn [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

    2017-05-01

    In this paper, we reported the synthesis of NiO/Ni bilayer nanotubes by electrodeposition and thermal oxidation using anodic aluminum oxide templates. The morphology, structure, chemical composition and magnetic properties, especially magnetic exchange bias induced by subsequent magnetic field cooling, in this one-dimensional antiferromagnetic/ferromagnetic hybrid system were investigated. It was found that the effect of the annealing temperature, which mainly dominated the thickness of the NiO layer, and the annealing time, which mainly dominated the grain size of the NiO, on the exchange bias field showed competitive relationship. The optimized exchange bias field was achieved by the combination of the shorter annealing time and higher annealing temperature. - Highlights: • NiO-Ni bilayer tubular nanotubes were fabricated by electrodeposition and thermal oxidation. • The exchange bias effect in NiO-Ni nanotubes was induced by magnetic field cooling. • The competitive effect of annealing temperature and annealing time on the exchange bias coupling was analyzed.

  16. Surveying and Comparing Thermal Conductivity and Physical Properties of Oil Base NanoFluids Containing Carbon and Metal Oxide Nanotubes

    Directory of Open Access Journals (Sweden)

    H. Ahmadi

    2012-12-01

    Full Text Available In this research, nano materials with tubular structures are added to SAE 20W50 engine oil to study the rate of their effects on the properties of engine oil. Multi-walled carbon nanotubes (MWCNTs and vanadium oxide nanotubes (VONTs has been used as two different additive materials, one of them is carbonic and the other is metallic oxides and their effect on  different parameters containing viscosity, thermal conductivity coefficient, flash point and pour point of engine oil as the quality properties of engine oil has been studied and compared. The samples of two concentrations 0.1 and 0.2 wt% with using planetary ball mill were made. The obtained results show that MWCNTs in all cases, which  have been evaluated, had better functionality with respect to vanadium oxide nanotubes. In the 0.1 wt% concentration, flash point of MWCNTs/oil and VONTs/oil increased about 9.3% and 5.8% respectively. In addition, thermal conductivity of them increased 13.2% and 10.2% respectively.

  17. CRISPR/Cas9-mediated targeted mutagenesis of GmFT2a delays flowering time in soya bean.

    Science.gov (United States)

    Cai, Yupeng; Chen, Li; Liu, Xiujie; Guo, Chen; Sun, Shi; Wu, Cunxiang; Jiang, Bingjun; Han, Tianfu; Hou, Wensheng

    2018-01-01

    Flowering is an indication of the transition from vegetative growth to reproductive growth and has considerable effects on the life cycle of soya bean (Glycine max). In this study, we employed the CRISPR/Cas9 system to specifically induce targeted mutagenesis of GmFT2a, an integrator in the photoperiod flowering pathway in soya bean. The soya bean cultivar Jack was transformed with three sgRNA/Cas9 vectors targeting different sites of endogenous GmFT2a via Agrobacterium tumefaciens-mediated transformation. Site-directed mutations were observed at all targeted sites by DNA sequencing analysis. T1-generation soya bean plants homozygous for null alleles of GmFT2a frameshift mutated by a 1-bp insertion or short deletion exhibited late flowering under natural conditions (summer) in Beijing, China (N39°58', E116°20'). We also found that the targeted mutagenesis was stably heritable in the following T2 generation, and the homozygous GmFT2a mutants exhibited late flowering under both long-day and short-day conditions. We identified some 'transgene-clean' soya bean plants that were homozygous for null alleles of endogenous GmFT2a and without any transgenic element from the T1 and T2 generations. These 'transgene-clean' mutants of GmFT2a may provide materials for more in-depth research of GmFT2a functions and the molecular mechanism of photoperiod responses in soya bean. They will also contribute to soya bean breeding and regional introduction. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  18. Effects of β-carotene on the thermal oxidation of fatty acids | Zeb ...

    African Journals Online (AJOL)

    β-Carotene is one of the most important fat soluble pigment with well known antioxidant and provitamin A activities. It is used in industries as food colorant and a source of vitamin A. The thermal induced degradation during processing leads to color and properties losses. The thermal stability of the fatty acids composition of ...

  19. Effects of β-carotene on the thermal oxidation of fatty acids

    African Journals Online (AJOL)

    Alamzeb

    β-Carotene is one of the most important fat soluble pigment with well known antioxidant and provitamin. A activities. It is used in industries as food colorant and a source of vitamin A. The thermal induced degradation during processing leads to color and properties losses. The thermal stability of the fatty acids composition of ...

  20. Composition dependence of the kinetics and mechanisms of thermal oxidation of titanium-tantalum alloys

    International Nuclear Information System (INIS)

    Park, Y.S.; Butt, D.P.

    1999-01-01

    The oxidation behavior of titanium-tantalum alloys was investigated with respective concentrations of each element ranging from 0 to 100 wt.%. Alloys were exposed to argon-20% oxygen at 800 to 1400 C. The slowest oxidation rates were observed in alloys with 5--20% Ta. The oxidation kinetics of alloys containing less than approximately 40% Ta were approximately parabolic. Pure Ta exhibited nearly linear kinetics. Alloys containing 50% or more Ta exhibited paralinear kinetics. The activation energies for oxidation ranged between 232 kJ/mole for pure Ti and 119 kJ/mole for pure Ta, with the activation energies of the alloys falling between these values and generally decreasing with increasing Ta content. The activation energies for oxidation of the end members, Ti and Ta, agree well with published values for the activation energies for diffusion of oxygen in α-Ti and Ta. Scale formation in the alloys was found to be complex exhibiting various layers of Ti-, Ta-, and TiTa-oxides. The outermost layer of the oxidized alloys was predominantly rutile (TiO 2 ). Beneath the TiO 2 grew a variety of other oxides with the Ta content generally increasing with proximity to the metal-oxide interface. It was found that the most oxidation-resistant alloys had compositions falling between Ti-5Ta and Ti-15Ta. Although Ta stabilizes the β-phase of Ti, the kinetics of oxidation appeared to be rate limited by oxygen transport through the oxygen-stabilized α-phase. However, the kinetics are complicated by the formation of a complex oxide, which cracks periodically. Tantalum appears to increase the compositional range of oxygen-stabilized α-phase and reduces both the solubility of oxygen and diffusivity of Ti in the α- and β-phases

  1. The conformational IgE epitope profile of soya bean allergen Gly m 4.

    Science.gov (United States)

    Husslik, F; Nürnberg, J; Seutter von Loetzen, C; Mews, T; Ballmer-Weber, B K; Kleine-Tebbe, J; Treudler, R; Simon, J-C; Randow, S; Völker, E; Reuter, A; Rösch, P; Vieths, S; Holzhauser, T; Schiller, D

    2016-11-01

    Birch pollen-related soya allergy is mediated by Gly m 4. Conformational IgE epitopes of Gly m 4 are unknown. To identify the IgE epitope profile of Gly m 4 in subjects with birch pollen-related soya allergy utilizing an epitope library presented by Gly m 4-type model proteins. Sera from patients with (n = 26) and without (n = 19) allergy to soya as determined by oral provocation tests were studied. Specific IgE (Bet v 1/Gly m 4) was determined by ImmunoCAP. A library of 59 non-allergenic Gly m 4-type model proteins harbouring individual and multiple putative epitopes for IgE was tested in IgE binding assays. Primary, secondary and tertiary protein structures were assessed by mass spectrometry, circular dichroism and nuclear magnetic resonance spectroscopy. All subjects were sensitized to Gly m 4 and Bet v 1. Allergen-specific serum IgE levels ranged from 0.94 to > 100 kU A /L. The avidities of serum IgE were 5.06 ng (allergic) and 1.8 ng (tolerant) as determined by EC 50 for IgE binding to Gly m 4. 96% (46/48) of the protein variants bound IgE. Model proteins had Gly m 4-type conformation and individual IgE binding clustered in six major surface areas. Gly m 4-specific IgE binding could be inhibited to up to 80% by model proteins harbouring individual IgE binding sites in an epitope-wise equimolar fashion. Receiver operating curve analysis revealed an area under fitted curve of up to 0.88 for model proteins and 0.66 for Gly m 4. Serum levels and avidity of Gly m 4-specific IgE do not correlate with clinical reactivity to soya. Six IgE-binding areas, represented by 23 amino acids, account for more than 80% of total IgE binding capacity of Gly m 4. Model proteins may be used for epitope-resolved diagnosis to differentiate birch-soya allergy from clinical tolerance. © 2016 John Wiley & Sons Ltd.

  2. Insight into the Mechanism of the Thermal Reduction of Graphite Oxide: Deuterium-Labeled Graphite Oxide Is the Key

    Czech Academy of Sciences Publication Activity Database

    Sofer, Z.; Jankovský, O.; Šimek, P.; Sedmidubský, D.; Šturala, J.; Kosina, J.; Mikšová, Romana; Macková, Anna; Mikulics, M.; Pumera, M.

    2015-01-01

    Roč. 9, č. 5 (2015), s. 5478-5485 ISSN 1936-0851 R&D Projects: GA ČR(CZ) GA15-09001S; GA ČR(CZ) GBP108/12/G108 Grant - others:GA MŠk(CZ) LM2010005 Institutional support: RVO:61389005 Keywords : graphene * exfoliation * mechanism * isotope labeling * graphite oxide Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 13.334, year: 2015

  3. Thermal Conductivity of Wurtzite Zinc-Oxide from First-Principles Lattice Dynamics – a Comparative Study with Gallium Nitride

    Science.gov (United States)

    Wu, Xufei; Lee, Jonghoon; Varshney, Vikas; Wohlwend, Jennifer L.; Roy, Ajit K.; Luo, Tengfei

    2016-01-01

    Wurtzite Zinc-Oxide (w-ZnO) is a wide bandgap semiconductor that holds promise in power electronics applications, where heat dissipation is of critical importance. However, large discrepancies exist in the literature on the thermal conductivity of w-ZnO. In this paper, we determine the thermal conductivity of w-ZnO using first-principles lattice dynamics and compare it to that of wurtzite Gallium-Nitride (w-GaN) – another important wide bandgap semiconductor with the same crystal structure and similar atomic masses as w-ZnO. However, the thermal conductivity values show large differences (400 W/mK of w-GaN vs. 50 W/mK of w-ZnO at room temperature). It is found that the much lower thermal conductivity of ZnO originates from the smaller phonon group velocities, larger three-phonon scattering phase space and larger anharmonicity. Compared to w-GaN, w-ZnO has a smaller frequency gap in phonon dispersion, which is responsible for the stronger anharmonic phonon scattering, and the weaker interatomic bonds in w-ZnO leads to smaller phonon group velocities. The thermal conductivity of w-ZnO also shows strong size effect with nano-sized grains or structures. The results from this work help identify the cause of large discrepancies in w-ZnO thermal conductivity and will provide in-depth understanding of phonon dynamics for the design of w-ZnO-based electronics. PMID:26928396

  4. Intake patterns and dietary associations of soya protein consumption in adults and children in the Canadian Community Health Survey, Cycle 2.2.

    Science.gov (United States)

    Mudryj, Adriana N; Aukema, Harold M; Yu, Nancy

    2015-01-28

    Soya foods are one of the recommended alternatives to meat in many dietary guidelines. While this is expected to increase the intake of some nutrients, potential concerns regarding others have been raised. The purpose of the present study was to examine the prevalence and the association of soya food consumption with nutrient intakes and dietary patterns of Canadians (age ≥ 2 years). Cross-sectional data from the 2004 Canadian Community Health Survey (Cycle 2.2; n 33,218) were used to classify soya consumers and non-consumers. Soya consumers were further divided into two groups based on their soya protein intake. Sample weights were applied and logistic regression analysis was used to explore the association between nutrient intakes and soya consumption, with cultural background, sex, age and economic status being included as covariates. On any given day, 3.3% (n 1085) of Canadians consume soya foods, with females, Asian Canadians and adults with post-secondary education being more likely to be soya consumers. As a whole, adolescent and adult respondents who had consumed at least one soya food during their 24 h dietary recall had higher energy intakes, as well as increased intakes of nutrients such as protein, fibre, vitamin C, vitamin B6, naturally occurring folate, thiamin, Ca, P, Mg, PUFA, Fe and K and lowered intakes of saturated fat. These data indicate that soya food consumption is associated with improved diet quality of Canadians. However, future research is necessary to investigate the association between increased energy intake and soya consumption.

  5. Effect of trypsin inhibitor activity in soya bean on growth performance, protein digestibility and incidence of sub-clinical necrotic enteritis in broiler chicken flocks.

    Science.gov (United States)

    Palliyeguru, M W C D; Rose, S P; Mackenzie, A M

    2011-06-01

    1. The effect of three different levels of dietary trypsin inhibitor activity (achieved by varying the amount of non-toasted full fat soya bean in replacement for toasted full fat soya bean) on the incidence of spontaneously-occurring sub-clinical necrotic enteritis (NE) in broiler chickens was compared. A fourth dietary treatment compared the effect of a diet that used potato protein concentrate as the major protein source. The determined trypsin inhibitor activity increased with the increasing content of non-toasted soya bean: 1·90, 6·21, 8·46 and 3·72 mg/g for the three soya bean diets (0, 100 and 200 g of non-toasted soya bean/kg) and the potato protein diet respectively. 2. Although increasing amounts of the non-toasted full-fat soya bean increased the feed intakes of the birds, there was a marked reduction in protein digestibility, weight gain and feed conversion efficiency. 3. There was a linear increase in sub-clinical NE lesions in the duodenum, jejunum, mid small intestine and ileum with increasing non-toasted soya bean. Caecal Clostridium perfringens counts increased with the increasing dietary content of non-toasted soya bean. Serum α-toxin antibodies were higher in the birds fed the 200 g non-toasted soya bean/kg diet compared with the other diets. 4. The results demonstrated that variation in the amount of non-toasted dietary soya bean not only affects growth performance of broilers but also affects the incidence of sub-clinical necrotic enteritis in the flock. Ensuring the lowest possible trypsin-inhibitor activity in soya bean samples is a valuable tool to improve the health and welfare of birds and in reducing the financial losses from this disease.

  6. Targeted kinetic strategy for improving the thermal conductivity of epoxy composite containing percolating multi-layer graphene oxide chains

    Directory of Open Access Journals (Sweden)

    T. Zhou

    2015-07-01

    Full Text Available By adding 2 wt% multi-layer graphene oxide (MGO to an epoxy resin, the thermal conductivity of the composite reached a maximum, 2.03 times that of the epoxy. The presence of 2 wt%MGO percolating chains leads to an unprecedentedly sharp rise in energy barrier at final curing stage, but an increased epoxy curing degree (αIR is observed; however, this αIR difference nearly disappears after aging or thermal annealing. These results suggest that the steep concentration gradient of –OH, originated from the 2 wt%MGO percolating chains, exerts the vital driving force on the residual isolated/trapped epoxy to conquer barrier for epoxy-MGO reaction. A modified Shrinking Core Model customized for the special layered-structure of MGO sheet was proposed to understand the resistance variation during the intercalative epoxy-MGO reaction. It shows that the promoted intercalative crosslinking is highly desirable for further improving the thermal conductivity of the composite, but it meets with increased resistance. Guided by the kinetic studies, targeted optimization on the cure processing strategy was accordingly proposed to promote the intercalative crosslinking, a thermal conductivity, 2.96 times that of the epoxy, was got with only a small amount (30°C increase of the post-heating temperature.

  7. Optical properties and thermal stability of LaYbO3 ternary oxide for high-k dielectric application

    Science.gov (United States)

    Su, Wei-tao; Yang, Li; Li, Bin

    2011-01-01

    A new ternary rare oxide dielectric LaYbO3 film had been prepared on silicon wafers and quartz substrates by reactive sputtering method using a La-Yb metal target. A range of analysis techniques was performed to determine the optical band gap, thermal stability, and electrical property of the deposited samples. It was found the band gap of LaYbO3 film was about 5.8 eV. And the crystallization temperature for rapid thermal annealing (20 s) was between 900 and 950 °C. X-ray photoelectron spectroscopy results indicate the formation of the SiO2 and silicate in the interface between silicon wafer and LaYbO3 film. The dielectric constant is about 23 from the calculation of capacitance-voltage curve, which is comparable higher than previously reported La2O3 or Yb2O3 film.

  8. HREM investigation of the constitution and the crystallography of thin thermal oxide layers on iron

    DEFF Research Database (Denmark)

    Graat, P.C.J.; Brongers, M.P.H.; Zandbergen, H.W.

    1997-01-01

    Oxide layers formed at 573 K in O2 at atmospheric pressure, both on a clean iron surface and on an iron surface covered with an etching induced (hydro)oxide film, were investigated with high-resolution transmission electron microscopy (HREM). Cross-sections of oxidised samples were prepared by a ...

  9. Ameliorating effect of olive oil on fertility of male rats fed on genetically modified soya bean

    Science.gov (United States)

    El-Kholy, Thanaa A. F.; Al-Abbadi, Hatim A.; Qahwaji, Dina; Al-Ghamdi, Ahmed K.; Shelat, Vishal G.; Sobhy, Hanan M.; Hilal, Mohammad Abu

    2015-01-01

    Background Genetically modified soya bean (GMSB) is a commercialized food. It has been shown to have adverse effects on fertility in animal trials. Extra virgin olive oil (EVOO) has many beneficial effects including anti-oxidant properties. The aim of this study is to elucidate if addition of EVOO ameliorates the adverse effects on reproductive organs of rats fed on GMSB containing diet. Methods Forty adult male albino rats (150–180 g) of Sprague Dawley strain were separated into four groups of 10 rats each: Group 1 – control group fed on basal ration, Group 2 – fed on basal ration mixed with EVOO (30%), Group 3 – fed on basal ration mixed with GMSB (15%), and Group 4 – fed on basal ration mixed with GMSB (15%) and EVOO (30%). This feeding regimen was administered for 65 days. Blood samples were collected to analyze serum zinc, vitamin E, and testosterone levels. Histopathological and weight changes in sex organs were evaluated. Results GMSB diet reduced weight of testis (0.66±0.06 vs. 1.7±0.06, p<0.001), epididymis (0.489±0.03 vs. 0.7±0.03, p<0.001), prostate (0.04±0.009 vs. 0.68±0.04, p<0.001), and seminal vesicles (0.057±0.01 vs. 0.8±0.04, p<0.001). GMSB diet adversely affected sperm count (406±7.1 vs. 610±7.8, p<0.001), motility (p<0.001), and abnormality (p<0.001). GMSB diet also reduced serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) concentrations. EVOO diet had no detrimental effect. Addition of EVOO to GMSB diet increased the serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) levels and also restored the weights of testis (1.35±0.16 vs. 0.66±0.06, p<0.01), epididymis (0.614±0.13 vs. 0.489±0.03, p<0.001), prostate (0.291±0.09 vs. 0.04±0.009, p<0.001), seminal vesicle (0.516±0.18 vs. 0.057±0.01, p<0.001) along with sperm count (516±3.1 vs. 406±7.1, p<0.01), motility (p<0.01), and abnormality (p<0.05). Conclusion EVOO ameliorates the adverse effects of GMSB on reproductive organs in adult male

  10. Ameliorating effect of olive oil on fertility of male rats fed on genetically modified soya bean

    Directory of Open Access Journals (Sweden)

    Thanaa A. F. El-Kholy

    2015-09-01

    Full Text Available Background: Genetically modified soya bean (GMSB is a commercialized food. It has been shown to have adverse effects on fertility in animal trials. Extra virgin olive oil (EVOO has many beneficial effects including anti-oxidant properties. The aim of this study is to elucidate if addition of EVOO ameliorates the adverse effects on reproductive organs of rats fed on GMSB containing diet. Methods: Forty adult male albino rats (150–180 g of Sprague Dawley strain were separated into four groups of 10 rats each: Group 1 – control group fed on basal ration, Group 2 – fed on basal ration mixed with EVOO (30%, Group 3 – fed on basal ration mixed with GMSB (15%, and Group 4 – fed on basal ration mixed with GMSB (15% and EVOO (30%. This feeding regimen was administered for 65 days. Blood samples were collected to analyze serum zinc, vitamin E, and testosterone levels. Histopathological and weight changes in sex organs were evaluated. Results: GMSB diet reduced weight of testis (0.66±0.06 vs. 1.7±0.06, p<0.001, epididymis (0.489±0.03 vs. 0.7±0.03, p<0.001, prostate (0.04±0.009 vs. 0.68±0.04, p<0.001, and seminal vesicles (0.057±0.01 vs. 0.8±0.04, p<0.001. GMSB diet adversely affected sperm count (406±7.1 vs. 610±7.8, p<0.001, motility (p<0.001, and abnormality (p<0.001. GMSB diet also reduced serum zinc (p<0.05, vitamin E (p<0.05, and testosterone (p<0.05 concentrations. EVOO diet had no detrimental effect. Addition of EVOO to GMSB diet increased the serum zinc (p<0.05, vitamin E (p<0.05, and testosterone (p<0.05 levels and also restored the weights of testis (1.35±0.16 vs. 0.66±0.06, p<0.01, epididymis (0.614±0.13 vs. 0.489±0.03, p<0.001, prostate (0.291±0.09 vs. 0.04±0.009, p<0.001, seminal vesicle (0.516±0.18 vs. 0.057±0.01, p<0.001 along with sperm count (516±3.1 vs. 406±7.1, p<0.01, motility (p<0.01, and abnormality (p<0.05. Conclusion: EVOO ameliorates the adverse effects of GMSB on reproductive organs in adult male

  11. Comparison of stabilization by Vitamin E and 2,6-di-tert-butylphenols during polyethylene radio-thermal-oxidation

    Science.gov (United States)

    Richaud, Emmanuel

    2014-10-01

    This paper reports a compilation of data for PE+Vitamin E and 2,6-di-tert-butylphenols oxidation in radio-thermal ageing. Data unambiguously show that Vitamin E reacts with Prad and POOrad whereas 2,6-di-tert-butyl phenols only react with POOrad. Kinetic parameters of the stabilization reactions for both kinds of antioxidants were tentatively extracted from phenol depletion curves, and discussed regarding the structure of the stabilizer. They were also used for completing an existing kinetic model used for predicting the stabilization by antioxidants. This one permits to compare the efficiency of stabilizer with dose rate or sample thickness.

  12. Rheological behavior, chemical and physical characterization of soybean and cottonseed methyl esters submitted to thermal oxidation process

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adriano Sant' ana; Silva, Flavio Luiz Honorato da; Lima, Ezenildo Emanuel de; Carvalho, Maria Wilma N.C. [Universidade Federal de Campina Grande (CCT/UFCG), PB (Brazil). Centro de Ciencia e Tecnologia; Dantas, Hemeval Jales; Farias, Paulo de Almeida [Universidade Federal de Campina Grande (CTRN/UFCG), PB (Brazil). Centro de Tecnologia e Recursos Naturais

    2008-07-01

    In this study the effect of antioxidant terc-butylhydroxyanisol (BHA) on the oxidative stability of soybean and cottonseed methyl esters subjected to thermal degradation at 100 deg C was studied. Soybean and cottonseed methyl esters specific mass, dynamic viscosity and rheological behavior were evaluated. According to results, antioxidant degraded samples specific mass and dynamic viscosity did not showed alterations, remaining statistically equal. Soybean and cottonseed methyl esters showed a Newtonian rheological behavior and degraded samples without adding BHA showed rheological behavior alterations. (author)

  13. Uranium-plutonium partitioning by pulsed column in the first cycle of the three cycle thermal oxide reprocessing plant

    International Nuclear Information System (INIS)

    Phillips, C.

    1992-01-01

    The Thermal Oxide Reprocessing Plant (THORP) is currently being commissioned at the Sellafield, England site of British Nuclear Fuels Plc, and will use the Purex process to reprocess irradiated oxide fuel from British, European and Japanese reactors. Careful initial design of the chemical flowsheet, combined with extensive small and full scale, fully active and inactive development work resulted in an efficient three cycle flowsheet with the minimum number of liquid waste streams. The use of salt-free reagents allows these wastes to be evaporated and vitrified for long term storage. The effect of technetium on the uranium-plutonium partitioning process and of neptunium on the purification of the uranium product received particular attention during the development work. (author)

  14. In Situ Analysis of the Li-O2 Battery with Thermally Reduced Graphene Oxide Cathode: Influence of Water Addition

    DEFF Research Database (Denmark)

    Storm, Mie Møller; Christensen, Mathias Kjærgård; Younesi, Reza

    2016-01-01

    The Li-O2 battery technology holds the promise to deliver a battery with significantly increased specific energy compared to today's Li-ion batteries. As a cathode support material, reduced graphene oxide has received increasing attention in the Li-O2 battery community due to the possibility...... of increased discharge capacity, increased battery cyclability, and decreased, charging, overpotential. In this. article we investigate the effect of water on a thermally, redircedigraphene, oxide cathode in a Li-O2 battery. Differential electrochemical mass spectrciscnieveals a, decreased electron count...... for batteries with 1000 ppm water added- to the electrolyte in comparison to dry batteries, indicating additional parasitic electrochemical or chemical processes. A comparable capacity of the wet and dry batteries indicates that the reaction mechanism in the Li-O2 battery also depends on the 'surface...

  15. Formation of polymerization compounds during thermal oxidation of cottonseed oil, partially hydrogenated cottonseed oil and their blends

    Directory of Open Access Journals (Sweden)

    Barrera-Arellano, D. Laboratório de Óleos e Gorduras, Departa

    2006-09-01

    Full Text Available Samples of cottonseed oil, partially hydrogenated cottonseed oil and their blends, with iodine values between 60 and 110, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C, for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds and of tocopherols. The influence of the degree of hydrogenation on the formation of dimers and polymers and the role of originally present tocopherols in the protection of fats and oils against thermal degradation was verified. The degradation curves for tocopherols showed a fast destruction rate for the tocopherols present in cottonseed fats and oil (α and γ-tocopherols, with residual levels close to zero after 10 hours under thermal oxidation conditions. Nevertheless, samples with their natural tocopherols presented a slower rate of thermal degradation. The unsaturation degree was apparently more important in the protection against thermal degradation than the content of tocopherolsMuestras de aceite de algodón, aceite de algodón parcialmente hidrogenado y sus mezclas, con índices de yodo de 60 a 110, tratadas o no con óxido de aluminio, fueron sometidas a termoxidación, a 180 °C, durante 10 horas. Se retiraron muestras en los tiempos 0, 2, 5, 8 y 10 horas, para determinación de dímeros y polímeros (compuestos de degradación y de tocoferoles. Se verificó la influencia del grado de hidrogenación sobre la formación de dímeros y polímeros, y también el papel de los tocoferoles originalmente presentes en el aceite y en las grasas, en la protección contra la degradación térmica. Las curvas de degradación de los tocoferoles mostraron una destrucción bastante rápida de los tocoferoles presentes en el aceite y en las grasas de algodón (α y γ-tocoferoles, con niveles residuales próximos a cero después de 10 horas de termoxidación. Aún así, muestras con sus

  16. Growth of Ga-doped ZnO films by thermal oxidation with gallium and their optical properties

    Directory of Open Access Journals (Sweden)

    Qing Yang

    2017-05-01

    Full Text Available Metal gallium was evaporated onto ZnS films by physical vapor deposition method and then the thermal oxidation in the air was subsequently performed for the growth of Ga-doped ZnO films. The microstructures, photoluminescence (PL and optical absorption properties of the Ga-doped ZnO films prepared under different deposition and oxidation conditions were investigated. The results showed that certain Ga doping can decrease the defects level, improve the crystallinity of ZnO films, and it became more effective with the extension of oxidation time. As the oxidation time increased, the Ga-doped ZnO films became more compact and uniform, displaying higher crystallinity. In addition, the optical band gaps of the ZnO films increased, the PL intensity of the visible emission decreased, and the luminescent center of the visible emission changed. Among them, the 505 nm emission resulted from oxygen vacancy, while the 539 nm emission was associated with oxygen interstitial.

  17. Physicochemical, structural and thermal properties of oxidized, acetylated and dual-modified common bean (Phaseolus vulgaris L. starch

    Directory of Open Access Journals (Sweden)

    José Pedro WOJEICCHOWSKI

    2018-03-01

    Full Text Available Abstract Common beans are rich in protein and complex carbohydrates that are valuable for the human diet. Starch is the most abundant individual component; however, in its native form it has limited applications and modifications are necessary to overcome technological restrictions. The aim of this study was to evaluate the influence of oxidation, acetylation and dual-modification (oxidation-acetylation on the physicochemical, structural and thermal properties of common bean starch. The degree of substitution of the acetylated starches was compatible with food use. Fourier transform infrared spectra confirmed the acetylation of the bean starch, with a peak at 1,735cm-1. The granules of the bean starch were oval to spherical in shape, with no differences between the native and modified samples. Typical C-type diffraction of legume starches was found. The modified samples showed a reduced relative crystallinity and lower enthalpy change of gelatinization. The oxidized starch showed the highest peak viscosity, hardness, and gel adhesiveness due to the presence of functional groups. An increase in solubility and swelling power was observed, and the oxidized-acetylated starch presented the highest values. The properties of the modified bean starches made them suitable for application in breaded/battered foods, mainly due to improved textural attributes.

  18. Natural printed silk substrate circuit fabricated via surface modification using one step thermal transfer and reduction graphene oxide

    Science.gov (United States)

    Cao, Jiliang; Huang, Zhan; Wang, Chaoxia

    2018-05-01

    Graphene conductive silk substrate is a preferred material because of its biocompatibility, flexibility and comfort. A flexible natural printed silk substrate circuit was fabricated by one step transfer of graphene oxide (GO) paste from transfer paper to the surface of silk fabric and reduction of the GO to reduced graphene oxide (RGO) using a simple hot press treatment. The GO paste was obtained through ultrasonic stirring exfoliation under low temperature, and presented excellent printing rheological properties at high concentration. The silk fabric was obtained a surface electric resistance as low as 12.15 KΩ cm-1, in the concentration of GO 50 g L-1 and hot press at 220 °C for 120 s. Though the whiteness and strength decreased with the increasing of hot press temperature and time slowly, the electric conductivity of RGO surface modification silk substrate improved obviously. The surface electric resistance of RGO/silk fabrics increased from 12.15 KΩ cm-1 to 18.05 KΩ cm-1, 28.54 KΩ cm-1 and 32.53 KΩ cm-1 after 10, 20 and 30 washing cycles, respectively. The results showed that the printed silk substrate circuit has excellent washability. This process requires no chemical reductant, and the reduction efficiency and reduction degree of GO is high. This time-effective and environmentally-friendly one step thermal transfer and reduction graphene oxide onto natural silk substrate method can be easily used to production of reduced graphene oxide (RGO) based flexible printed circuit.

  19. Enhancing the Photovoltage of Ni/ n-Si Photoanode for Water Oxidation through a Rapid Thermal Process.

    Science.gov (United States)

    Li, Shengyang; She, Guangwei; Chen, Cheng; Zhang, Shaoyang; Mu, Lixuan; Guo, Xiangxin; Shi, Wensheng

    2018-03-14

    The Ni in the Ni/ n-Si photoanode can not only protect Si from corrosion, but also catalyze the water oxidation reaction. However, the high density of interface states at the Ni/ n-Si interface could pin the Fermi level of silicon, which will lower the Schottky barrier height of the Ni/ n-Si. As a result, a low photovoltage and consequent high onset potential of Ni/ n-Si photoanode for water oxidation were generated. In this study, the interfacial states of the Ni/ n-Si photoanodes were efficiently diminished through a rapid thermal process (RTP). Calculated from the Mott-Schottky plots, the Schottky barrier height of Ni/ n-Si was increased from 0.58 to 0.78 eV after RTP. Under the illumination of 100 mW cm -2 of the Xe lamp, the onset potential of the Ni/ n-Si photoanode for water oxidation was negatively shifted for 150 mV after RTP. Besides, the RTP-treated Ni/ n-Si photoanode exhibited a high stability during the PEC water oxidation of 8 h in 1 M KOH solution.

  20. Soya-cerebroside, an extract of Cordyceps militaris, suppresses monocyte migration and prevents cartilage degradation in inflammatory animal models

    Science.gov (United States)

    Liu, Shan-Chi; Chiu, Ching-Peng; Tsai, Chun-Hao; Hung, Chun-Yin; Li, Te-Mao; Wu, Yang-Chang; Tang, Chih-Hsin

    2017-01-01

    Pathophysiological events that modulate the progression of structural changes in osteoarthritis (OA) include the secretion of inflammatory molecules, such as proinflammatory cytokines. Interleukin-1beta (IL-1β) is the prototypical inflammatory cytokine that activates OA synovial cells to release cytokines and chemokines in support of the inflammatory response. The monocyte chemoattractant protein-1 (MCP-1/CCL2) is one of the key chemokines that regulate migration and infiltration of monocytes in response to inflammation. We show in this study that IL-1β-induced MCP-1 expression and monocyte migration in OA synovial fibroblasts (OASFs) is effectively inhibited by soya-cerebroside, an extract of Cordyceps militaris. We found that soya-cerebroside up-regulated of microRNA (miR)-432 expression via inhibiting AMPK and AKT signaling pathways in OASFs. Soya-cerebroside also effectively decreased monocyte infiltration and prevented cartilage degradation in a rat inflammatory model. Our findings are the first to demonstrate that soya-cerebroside inhibits monocyte/macrophage infiltration into synoviocytes, attenuating synovial inflammation and preventing cartilage damage by reducing MCP-1 expression in vitro and in vivo. Taken together, we suggest a novel therapeutic strategy based on the use of soya-cerebroside for the management of OA. PMID:28225075

  1. Preparation and thermal properties of form-stable palmitic acid/active aluminum oxide composites as phase change materials for latent heat storage

    International Nuclear Information System (INIS)

    Fang, Guiyin; Li, Hui; Cao, Lei; Shan, Feng

    2012-01-01

    Form-stable palmitic acid (PA)/active aluminum oxide composites as phase change materials were prepared by adsorbing liquid palmitic acid into active aluminum oxide. In the composites, the palmitic acid was used as latent heat storage materials, and the active aluminum oxide was used as supporting material. Fourier transformation infrared spectroscope (FT-IR), X-ray diffractometer (XRD) and scanning electronic microscope (SEM) were used to determine the chemical structure, crystalloid phase and microstructure of the composites, respectively. The thermal properties and thermal stability were investigated by a differential scanning calorimeter (DSC) and a thermogravimetry analyzer (TGA). The FT-IR analyses results indicated that there is no chemical interaction between the palmitic acid and active aluminum oxide. The SEM results showed that the palmitic acid was well adsorbed into porous network of the active aluminum oxide. The DSC results indicated that the composites melt at 60.25 °C with a latent heat of 84.48 kJ kg −1 and solidify at 56.86 °C with a latent heat of 78.79 kJ kg −1 when the mass ratio of the PA to active aluminum oxide is 0.9:1. Compared with that of the PA, the melting and solidifying time of the composites CPCM5 was reduced by 20.6% and 21.4% because of the increased heat transfer rate through EG addition. The TGA results showed that the active aluminum oxide can improve the thermal stability of the composites. -- Highlights: ► Form-stable PA/active aluminum oxide composites as PCMs were prepared. ► Chemical structure, crystalloid phase and microstructure of composites were determined. ► Thermal properties and thermal stability of the composites were investigated. ► Expanded graphite can improve thermal conductivity of the composites.

  2. Processing and Deposition of Nanocrystalline Oxide Composites for Thermal Barrier Coatings

    National Research Council Canada - National Science Library

    Ying, Jackie

    2000-01-01

    .... Electrophoretic deposition was used to coat the nanocomposite powders onto nickel substrates. The effect of alumina content, powder calcination temperature, and film thickness on the thermal stability of zirconia-based coatings was examined...

  3. Mechanical and Thermal Properties of Epoxy Composites Containing Zirconium Oxide Impregnated Halloysite Nanotubes

    OpenAIRE

    Moon il Kim; Suhyun Kim; Taehee Kim; Dong Koo Lee; Bongkuk Seo; Choong-Sun Lim

    2017-01-01

    Liquid epoxy resins have received much attention from both academia and the chemical industry as eco-friendly volatile organic compound (VOC)-free alternatives for applications in coatings and adhesives, especially in those used in households. Epoxy resins show high chemical resistance and high creep resistance. However, due to their brittleness and lack of thermal stability, additional fillers are needed for improving the mechanical and thermal properties. Halloysite nanotubes (HNTs) are nat...

  4. Thermal oxidation of single crystal aluminum antimonide and materials having the same

    Energy Technology Data Exchange (ETDEWEB)

    Sherohman, John William; Yee, Jick Hong; Coombs, III, Arthur William; Wu, Kuang Jen J.

    2012-12-25

    In one embodiment, a method for forming a non-conductive crystalline oxide layer on an AlSb crystal includes heat treating an AlSb crystal in a partial vacuum atmosphere at a temperature conducive for air adsorbed molecules to desorb, surface molecule groups to decompose, and elemental Sb to evaporate from a surface of the AlSb crystal and exposing the AlSb crystal to an atmosphere comprising oxygen to form a crystalline oxide layer on the surface of the AlSb crystal. In another embodiment, a method for forming a non-conductive crystalline oxide layer on an AlSb crystal includes heat treating an AlSb crystal in a non-oxidizing atmosphere at a temperature conducive for decomposition of an amorphous oxidized surface layer and evaporation of elemental Sb from the AlSb crystal surface and forming stable oxides of Al and Sb from residual surface oxygen to form a crystalline oxide layer on the surface of the AlSb crystal.

  5. Thermal and Physical Properties of Plutonium Dioxide Produced from the Oxidation of Metal: a Data Summary

    Energy Technology Data Exchange (ETDEWEB)

    Wayne, David M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-13

    The ARIES Program at the Los Alamos National Laboratory removes plutonium metal from decommissioned nuclear weapons, and converts it to plutonium dioxide in a specially-designed Direct Metal Oxidation furnace. The plutonium dioxide is analyzed for specific surface area, particle size distribution, and moisture content. The purpose of these analyses is to certify that the plutonium dioxide powder meets or exceeds the specifications of the end-user, and the specifications for the packaging and transport of nuclear materials. Analytical results from plutonium dioxide from ARIES development activities, from ARIES production activities, from muffle furnace oxidation of metal, and from metal that was oxidized over a lengthy time interval in air at room temperature, are presented. The processes studied produce plutonium dioxide powder with distinct differences in measured properties, indicating the significant influence of oxidation conditions on physical properties.

  6. Fabrication and Optoelectrical Properties of IZO/Cu2O Heterostructure Solar Cells by Thermal Oxidation

    Directory of Open Access Journals (Sweden)

    Cheng-Chiang Chen

    2012-01-01

    Full Text Available Indium zinc oxide (IZO/cupper oxide (Cu2O is a nontoxic nature and an attractive all-oxide candidate for low-cost photovoltaic (PV applications. The present paper reports on the fabrication of IZO/Cu2O heterostructure solar cells which the Cu2O layers were prepared by oxidation of Cu thin films deposited on glass substrate. The measured parameters of cells were the short-circuit current (Isc, the open-circuit voltage (Voc, the maximum output power (Pm, the fill factor (FF, and the efficiency (η, which had values of 0.11 mA, 0.136 V, 5.05 μW, 0.338, and 0.56%, respectively, under AM 1.5 illumination.

  7. Water absorption in thermally grown oxides on SiC and Si: Bulk oxide and interface properties

    Science.gov (United States)

    Liu, Gang; Xu, Can; Yakshinskiy, Boris; Wielunski, Leszek; Gustafsson, Torgny; Bloch, Joseph; Dhar, Sarit; Feldman, Leonard C.

    2014-11-01

    We combine nuclear reaction analysis and electrical measurements to study the effect of water exposure (D2O) on the n-type 4H-SiC carbon face (000 1 ¯ ) MOS system and to compare to standard silicon based structures. We find that: (1) The bulk of the oxides on Si and SiC behave essentially the same with respect to deuterium accumulation; (2) there is a significant difference in accumulation of deuterium at the semiconductor/dielectric interface, the SiC C-face structure absorbs an order of magnitude more D than pure Si; (3) standard interface passivation schemes such as NO annealing greatly reduce the interfacial D accumulation; and (4) the effective interfacial charge after D2O exposure is proportional to the total D amount at the interface.

  8. Positron beam and RBS studies of thermally grown oxide films on stainless steel grade 304

    Science.gov (United States)

    Horodek, P.; Siemek, K.; Kobets, A. G.; Kulik, M.; Meshkov, I. N.

    2015-04-01

    The formation of oxide films on surfaces of stainless steel 304 AISI annealed at 800 °C in vacuum, air and in flow N2 atmospheres was studied using variable energy positron beam technique (VEP) and Rutherford backscattering/nuclear reaction (RBS/NR) methods. In frame of these studies, Doppler broadening of annihilation line (DB) measurements were performed. For a sample heated in vacuum the oxide film ca. 8 nm is observed. For specimens oxidized in air and N2 the multi-layered oxide films of about a few hundred nanometers are recognized. The RBS/NR measurements have shown that the sample annealed in vacuum contains a lower quantity of oxygen while for samples heated in the air and N2 non-linear and rather linear time-dependency are observed, respectively. The thicknesses of total oxide films obtained from RBS/NR tests are in good agreement with the VEP results. Time evolution of the oxide growing was studied as well.

  9. Thermal hazard assessment of oxidizer solutions and emulsion explosives utilizing accelerating rate and Dewar calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.E.G.; Lightfoot, P.D.; Fouchard, R.C. [Natural Resources Canada, CANMET, Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2002-07-01

    Accelerating rate calorimetry (ARC) and adiabatic Dewar calorimetric experiments were carried out on oxidizers used in the manufacture of emulsion explosives, their aqueous solutions, a bulk explosive matrix and a detonator-sensitive packaged explosive. The experiments were carried out in both closed and vented experimental configurations. The effects of water levels on the oxidizer solutions were investigated and the results obtained by using the two different techniques were compared. The Dewar experiments were found to yield a better direct estimation of bulk onset temperatures due to their greater sensitivity and lower 'phi factor'. Onset temperatures of oxidizer solutions measured using the Dewar calorimeter were found to be about 15 degrees C lower than those measured by ARC. Onset temperatures for the same oxidizer solution are lower for open systems than for closed systems. Results for emulsion explosives appeared complex, but indications are that oxidation of the oil phase in air is the first exothermic step in the runaway reaction. Whether this oxidation reaction can generate enough heat to drive the reaction to runaway, is not clear. Further elucidation of the complex exothermic reactions of emulsion explosives and their constituents, using both ARC and Dewar calorimetric techniques is recommended. 8 refs., 1 tab., 9 figs.

  10. A UPS study of the thermal reduction of fully oxidized V2O5/TiO2(001-anatase) model catalysts

    International Nuclear Information System (INIS)

    Silversmit, G.; Poelman, H.; Depla, D.; Poelman, D.; DE Gryse, R.; Marin, G.B.; Barrett, N.

    2004-01-01

    Full text: Vanadium oxides are important catalysts in various industrial processes. Supported vanadium oxides have enhanced catalytic properties as compared to unsupported vanadium oxides. Model systems, consisting of a thin vanadium oxide layer deposited on a crystalline support, are used to study supported vanadium oxides. As calcined industrial powder systems contain V 5+ , representative model systems should also have fully oxidized vanadium oxide layers. DC magnetron sputtering in a pure O 2 atmosphere is used as deposition technique in order to develop fully oxidized V 2 O 5 /TiO 2 (001-anatase) model catalysts. Vanadium oxide layers deposited with magnetron sputtering on mineral TiO 2 (001-anatase) supports were examined with UPS (hv=150 eV) at the SA73 beamline of the S.ACO storage ring (LURE, France) by recording the valence band and the V3p, Ti3p and O2s core line spectra. Ex-situ depositions did not yield fully oxidized vanadium oxide layers. Fully oxidized vanadium oxide layers on TiO 2 (001-anatase) can be obtained by in-situ depositions. The in-situ deposited layers are gradually reduced upon irradiation with the monochromated synchrotron beam. The thermal behaviour of the V 2 O 5 /TiO 2 (001-anatase) system was studied up to approximately 240 deg C for a layer thickness of 16 Angstroms. The heating induced a reduction of the vanadium oxide layer. Furthermore, the thickness of the layers diminished by the heating: more than 8 Angstroms vanadium oxide disappeared. A re-oxidation did not restore the vanadium oxide layer completely to the V 5+ oxidation state

  11. Preparation, optical properties, magnetic properties and thermal stability of core-shell structure cobalt/zinc oxide nanocomposites

    International Nuclear Information System (INIS)

    Bala, Hari; Fu Wuyou; Yu Yanhui; Yang Haibin; Zhang Yishun

    2009-01-01

    Cobalt nanoparticles coated with zinc oxide can form composite spheres with core-shell structure. This coating process was based on the use of silane coupling with agent 3-mercaptopropyltrimethoxysilane (HS-(CH 2 ) 3 Si(OCH 3 ) 3 , MPTS) as a primer to render the cobalt surface vitreophilic, thus it renders cobalt surface compatible with ZnO. X-ray photoelectron spectroscopy (XPS) was used to gain insight into the way in which the MPTS is bound to the surface of the cobalt nanoparticles. The morphological structure, chemical composition, optical properties and magnetic properties of the product were investigated by using transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), photoluminescence (PL) spectroscope and vibrating sample magnetometer (VSM). It was found that the Co/ZnO core-shell structure nanocomposites exhibited both of favorable magnetism and photoluminescence properties. Results of the thermogravimetric analysis (TGA) and differential thermal analysis (DTA) indicated that the thermal stability of cobalt/zinc oxide was better than that of pure cobalt nanoparticles.

  12. Adaptation, validation and application of the chemo-thermal oxidation method to quantify black carbon in soils

    International Nuclear Information System (INIS)

    Agarwal, Tripti; Bucheli, Thomas D.

    2011-01-01

    The chemo-thermal oxidation method at 375 o C (CTO-375) has been widely used to quantify black carbon (BC) in sediments. In the present study, CTO-375 was tested and adapted for application to soil, accounting for some matrix specific properties like high organic carbon (≤39%) and carbonate (≤37%) content. Average recoveries of standard reference material SRM-2975 ranged from 25 to 86% for nine representative Swiss and Indian samples, which is similar to literature data for sediments. The adapted method was applied to selected samples of the Swiss soil monitoring network (NABO). BC content exhibited different patterns in three soil profiles while contribution of BC to TOC was found maximum below the topsoil at all three sites, however at different depths (60-130 cm). Six different NABO sites exhibited largely constant BC concentrations over the last 25 years, with short-term (6 months) prevailing over long-term (5 years) temporal fluctuations. - Research highlights: → The CTO-375 method was adapted and validated for BC analysis in soils. → Method validation figures of merit proofed satisfactory. → Application is shown with soil cores and topsoil temporal variability. → BC content can be elevated in subsurface soils. → BC contents in surface soils were largely constant over the last 25 years. - Although widely used also for soils, the chemo-thermal oxidation method at 375 o C to quantify black carbon has never been properly validated for this matrix before.

  13. Characteristics of hydrogen produced by partial oxidation and auto-thermal reforming in a small methanol reformer

    Science.gov (United States)

    Horng, Rong-Fang; Chou, Huann-Ming; Lee, Chiou-Hwang; Tsai, Hsien-Te

    This paper investigates experimentally, the transient characteristics of a small methanol reformer using partial oxidation (POX) and auto-thermal reforming (ATR) for fuel cell applications. The parameters varied were heating temperature, methanol supply rate, steady mode shifting temperature, O 2/C (O 2/CH 3OH) and S/C (H 2O/CH 3OH) molar ratios with the main aim of promoting a rapid response and a high flow rate of hydrogen. The experiments showed that a high steady mode shifting temperature resulted in a faster temperature rise at the catalyst outlet and vice versa and that a low steady mode shifting temperature resulted in a lower final hydrogen concentration. However, when the mode shifting temperature was too high, the hydrogen production response was not necessarily improved. It was subsequently shown that the optimum steady mode shifting temperature for this experimental set-up was approximately 75 °C. Further, the hydrogen concentration produced by the auto-thermal process was as high as 49.12% and the volume flow rate up to 23.0 L min -1 compared to 40.0% and 20.5 L min -1 produced by partial oxidation.

  14. Preparation, optical properties, magnetic properties and thermal stability of core-shell structure cobalt/zinc oxide nanocomposites

    Science.gov (United States)

    Bala, Hari; Fu, Wuyou; Yu, Yanhui; Yang, Haibin; Zhang, Yishun

    2009-01-01

    Cobalt nanoparticles coated with zinc oxide can form composite spheres with core-shell structure. This coating process was based on the use of silane coupling with agent 3-mercaptopropyltrimethoxysilane (HS-(CH 2) 3Si(OCH 3) 3, MPTS) as a primer to render the cobalt surface vitreophilic, thus it renders cobalt surface compatible with ZnO. X-ray photoelectron spectroscopy (XPS) was used to gain insight into the way in which the MPTS is bound to the surface of the cobalt nanoparticles. The morphological structure, chemical composition, optical properties and magnetic properties of the product were investigated by using transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), photoluminescence (PL) spectroscope and vibrating sample magnetometer (VSM). It was found that the Co/ZnO core-shell structure nanocomposites exhibited both of favorable magnetism and photoluminescence properties. Results of the thermogravimetric analysis (TGA) and differential thermal analysis (DTA) indicated that the thermal stability of cobalt/zinc oxide was better than that of pure cobalt nanoparticles.

  15. Preparation, optical properties, magnetic properties and thermal stability of core-shell structure cobalt/zinc oxide nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Bala, Hari [Institute of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000 (China); State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)], E-mail: hari@hpu.edu.cn; Fu Wuyou [National Laboratory for Superhard Materials, JiIin University, Changchun 130023 (China); Yu Yanhui [Institute of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000 (China); Yang Haibin [Institute of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000 (China); National Laboratory for Superhard Materials, JiIin University, Changchun 130023 (China); Zhang Yishun [Institute of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000 (China)

    2009-01-15

    Cobalt nanoparticles coated with zinc oxide can form composite spheres with core-shell structure. This coating process was based on the use of silane coupling with agent 3-mercaptopropyltrimethoxysilane (HS-(CH{sub 2}){sub 3}Si(OCH{sub 3}){sub 3}, MPTS) as a primer to render the cobalt surface vitreophilic, thus it renders cobalt surface compatible with ZnO. X-ray photoelectron spectroscopy (XPS) was used to gain insight into the way in which the MPTS is bound to the surface of the cobalt nanoparticles. The morphological structure, chemical composition, optical properties and magnetic properties of the product were investigated by using transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), photoluminescence (PL) spectroscope and vibrating sample magnetometer (VSM). It was found that the Co/ZnO core-shell structure nanocomposites exhibited both of favorable magnetism and photoluminescence properties. Results of the thermogravimetric analysis (TGA) and differential thermal analysis (DTA) indicated that the thermal stability of cobalt/zinc oxide was better than that of pure cobalt nanoparticles.

  16. Magnetic, thermal and luminescence properties in room-temperature nanosecond electron-irradiated various metal oxide nanopowders

    Science.gov (United States)

    Sokovnin, S. Yu; Balezin, M. E.; Il’ves, V. G.

    2018-03-01

    By means of pulsed electron beam evaporation in vacuum of targets non-magnetic, in bulk state, Al2O3 and YSZ (ZrO2-8% Y2O3) oxides, magnetic nanopowders (NPs) with a high specific surface were produced. The NPs were subsequently irradiated in air by electrons with energy of 700 keV, using a URT-1 accelerator for 15 and 30 minutes. The magnetic, thermal, and pulsed cathodoluminescence (PCL) characteristics of NPs were measured before and after irradiation. It was established that the electron irradiation non-monotonically changes the magnetization of the pristine samples. To the contrary, a clear correlation between the intensity of PCL and the irradiation doses is found in the oxides. There was a decrease in the intensity of PCL after irradiation. Luminescent and thermal properties reflect the transformation of structural defects in NPs more strongly after the exposure to a pulsed electron beam in comparison with corresponding changes of the NPs magnetic response.

  17. Removal of formaldehyde over Mn(x)Ce(1)-(x)O(2) catalysts: thermal catalytic oxidation versus ozone catalytic oxidation.

    Science.gov (United States)

    Li, Jia Wei; Pan, Kuan Lun; Yu, Sheng Jen; Yan, Shaw Yi; Chang, Moo Been

    2014-12-01

    Mn(x)Ce(1)-(x)O(2) (x: 0.3-0.9) prepared by Pechini method was used as a catalyst for the thermal catalytic oxidation of formaldehyde (HCHO). At x=0.3 and 0.5, most of the manganese was incorporated in the fluorite structure of CeO(2) to form a solid solution. The catalytic activity was best at x=0.5, at which the temperature of 100% removal rate is the lowest (270°C). The temperature for 100% removal of HCHO oxidation is reduced by approximately 40°C by loading 5wt.% CuO(x) into Mn(0.5)Ce(0.5)O(2). With ozone catalytic oxidation, HCHO (61 ppm) in gas stream was completely oxidized by adding 506 ppm O₃over Mn(0.5)Ce(0.5)O(2) catalyst with a GHSV (gas hourly space velocity) of 10,000 hr⁻¹ at 25°C. The effect of the molar ratio of O(3) to HCHO was also investigated. As O(3)/HCHO ratio was increased from 3 to 8, the removal efficiency of HCHO was increased from 83.3% to 100%. With O(3)/HCHO ratio of 8, the mineralization efficiency of HCHO to CO(2) was 86.1%. At 25°C, the p-type oxide semiconductor (Mn(0.5)Ce(0.5)O(2)) exhibited an excellent ozone decomposition efficiency of 99.2%, which significantly exceeded that of n-type oxide semiconductors such as TiO(2), which had a low ozone decomposition efficiency (9.81%). At a GHSV of 10,000 hr⁻¹, [O(3)]/[HCHO]=3 and temperature of 25°C, a high HCHO removal efficiency (≥ 81.2%) was maintained throughout the durability test of 80 hr, indicating the long-term stability of the catalyst for HCHO removal. Copyright © 2014. Published by Elsevier B.V.

  18. Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Knudsen, Sven David Lausten; Jutfelt, Fredrik; Sundh, Henrik

    2008-01-01

    are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins...... increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels...... of added soya saponins, one diet containing 25 % lupin kernel meal, two diets based on 25 % lupin kernel meal with different levels of added soya saponins, and one diet containing 25 % defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content...

  19. Final Report: Fiscal Year 1997 demonstration of omnivorous non-thermal mixed waste treatment: Direct chemical oxidation of organic solids and liquids using peroxydisulfate

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, J.F.

    1998-01-01

    Direct Chemical Oxidation (DCO) is a non-thermal, ambient pressure, aqueous-based technology for the oxidative destruction of the organic components of hazardous or mixed waste streams. The process has been developed for applications in waste treatment, chemical demilitarization and decontamination at LLNL since 1992. The process uses solutions of the peroxydisulfate ion (typically sodium or ammonium salts) to completely mineralize the organics to carbon dioxide and water. The expended oxidant may be electrolytically regenerated to minimize secondary waste. The paper briefly describes: free radical and secondary oxidant formation; electrochemical regeneration; offgas stream; and throughput.

  20. Final Report: Fiscal Year 1997 demonstration of omnivorous non-thermal mixed waste treatment: Direct chemical oxidation of organic solids and liquids using peroxydisulfate

    International Nuclear Information System (INIS)

    Cooper, J.F.; Ballazs G.B.

    1998-01-01

    Direct Chemical Oxidation (DCO) is a non-thermal, ambient pressure, aqueous-based technology for the oxidative destruction of the organic components of hazardous or mixed waste streams. The process has been developed for applications in waste treatment, chemical demilitarization and decontamination at LLNL since 1992. The process uses solutions of the peroxydisulfate ion (typically sodium or ammonium salts) to completely mineralize the organics to carbon dioxide and water. The expended oxidant may be electrolytically regenerated to minimize secondary waste. The paper briefly describes: free radical and secondary oxidant formation; electrochemical regeneration; offgas stream; and throughput

  1. Soya bean meal increases litter moisture and foot pad dermatitis in maize and wheat based diets for turkeys but maize and non-soya diets lower body weight.

    Science.gov (United States)

    Hocking, P M; Vinco, L J; Veldkamp, T

    2018-04-01

    1. A 2 × 2 factorial experiment was conducted to compare the effects of wheat or maize based diets differing in dietary electrolyte balance (DEB) on litter moisture and foot pad dermatitis (FPD) at 4, 8 and 12 weeks of age in heavy-medium turkeys. A second objective was to investigate the effects on foot pad dermatitis of the interaction between dietary composition and artificially increasing litter moisture by adding water to the litter. 2. High DEB diets contained soya as the main protein source whereas low DEB diets did not contain soya bean meal. Diets were formulated to be iso-caloric and iso-nitrogenous in each of 3 successive 4-week phases following recommended dietary compositions. DEB concentrations were 330, 290 and 250 mEq/kg in high DEB diets and 230, 200 and 180 mEq/kg in low DEB diets. 3. Litter moisture and mean FPD score were higher in turkeys fed on high DEB diets compared with low DEB diets whereas there was no difference between maize and wheat. 4. Food intake was similar and body weight was lower after litter moisture was artificially raised in the wet compared with the dry litter treatment and there was no interaction with dietary composition. 5. Mean body weight and feed intake were higher in turkeys fed on wheat compared with maize and in high DEB compared with low DEB diets at 12 weeks of age. 6. Lowering dietary DEB for turkeys may improve litter moisture and lower the prevalence of FPD in commercial turkey flocks.

  2. Thermal oxidation of hydrogen sulfide associated to a petroleum reservoir submitted to in-situ combustion in the Orinoco oil belt

    Energy Technology Data Exchange (ETDEWEB)

    Perozo, H.A.; Belandria, V. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of). INTEVEP

    2009-07-01

    This paper described an in-situ combustion (ISC) pilot project that is being developed by Venezuela's state oil company in the Orinoco oil belt. Thermal oxidation is commonly used to remove contaminants from waste gases. Petroleos de Venezuela SA examined the effectiveness of this process for eliminating hydrogen sulfide (H{sub 2}S) from flue gas associated with heavy oil thermal upgrading projects, with particular focus on the effect of temperature on H{sub 2}S oxidation. Laboratory-scale experiments were conducted in an isothermal batch reactor at temperatures between 200 and 500 degrees C. A synthetic gas stream was prepared. The experimental results showed that it is feasible to oxidize 100 per cent of the H{sub 2}S at temperatures as low as 300 degrees C by optimizing excess air and residence time in the reactor. Compared to the minimum required temperature of 760 degrees C to reach 98 per cent oxidation efficiency of H{sub 2}S in the conventional thermal oxidation process of most sour gases, this study found a lower temperature that satisfactorily eliminates H{sub 2}S for the desired application. The results confirmed the feasibility of using thermal oxidation to deal with H{sub 2}S in the flue gas stream during the application of ISC. 5 refs., 8 tabs., 5 figs.

  3. Characterization of thermal reaction of aluminum/copper (II) oxide/poly(tetrafluoroethene) nanocomposite by thermogravimetric analysis, differential scanning calorimetry, mass spectrometry and X-ray diffraction

    International Nuclear Information System (INIS)

    Li, Xiangyu; Yang, Hongtao; Li, Yan-chun

    2015-01-01

    Highlights: • The thermal reaction properties of the Al/CuO/PTFE nanocomposite were investigated. • The Al/PTFE and CuO/PTFE nanocomposites were prepared and tested for comparison. • TG/DSC–MS and XRD analysis were performed. • PTFE is oxidizing Al and reducing CuO during the thermal decomposition. - Abstract: The application of fluoropolymers as reactive agent in energetic materials have attracted significant interest recently. In this study, the thermal reaction properties of the aluminum nanoparticles/copper (II) oxide nanoparticles/poly(tetrafluoroethene) (Al-NPs/CuO-NPs/PTFE) nanocomposite (mass ratio of Al-NPs/CuO-NPs/PTFE = 20/60/20) were investigated by means of thermogravimetry/differential scanning calorimetry–mass spectrometry (TG/DSC–MS) and X-ray diffraction (XRD) analyses. The Al-NPs/PTFE (mass ratio of Al-NPs/PTFE = 50/50) and CuO-NPs/PTFE (mass ratio of CuO-NPs/PTFE = 75/25) nanocomposites were also prepared and tested for comparison. It is observed that PTFE is acting as both oxidizer and reducer during the thermal decomposition process of Al-NPs/CuO-NPs/PTFE nanocomposites. Before 615 °C, PTFE is oxidized by CuO-NPs and oxidizing Al-NPs, resulting mass reduction. After 615 °C, the excessive aluminum and copper (I)/copper (II) oxide will proceed the exothermic condensed phase reaction.

  4. Effects of Sintering on the Thermal and Optical Properties of Zinc Oxide Ceramic

    Science.gov (United States)

    Tabasco-Novelo, C.; May-Crespo, J.; Ramírez-Rincón, J. A.; Forero-Sandoval, I. Y.; Rodríguez-Gattorno, G.; Quintana, P.; Alvarado-Gil, J. J.

    2018-02-01

    Microstructure and composition are factors determining heat transfer in ZnO ceramic materials, which define the performance of the material after Joule heating, generated by electron transport. In this study, photothermal radiometry was applied to investigate the influence of the sintering temperature, ranging from 800 {°}C to 1300 {°}C, by measuring the thermal diffusivity and thermal conductivity at room temperature, of commercial and sol-gel ZnO pellets. Our results show that the values of these thermal properties for both types of ZnO increase when the sintering temperature increases, displaying maximum energy dissipation at 1200 {°}C. Additionally, the role of the sintering temperature on the optical properties was also analyzed using diffuse reflectance spectroscopy, and from these data the optical band-gap was obtained.

  5. Isochoric thermal conductivity of solid carbon oxide: the role of phonons and 'diffusive' modes

    International Nuclear Information System (INIS)

    Konstantinov, V A; Manzhelii, V G; Revyakin, V P; Sagan, V V; Pursky, O I

    2006-01-01

    The isochoric thermal conductivity of solid CO was investigated in three samples of different densities in the interval from 35 K to the onset of melting. In α-CO the temperature dependence of the isochoric thermal conductivity is significantly weaker than Λ∝1/T; in β-CO it increases slightly with temperature. A quantitative description of the experimental results is given within the Debye model of thermal conductivity in the approximation of the corresponding relaxation times and which allows for the fact that the mean-free path of phonons cannot become smaller than half the phonon wavelength. On this consideration the heat is transported by both phonons and 'diffusive' modes

  6. Investigation of Molecular Structure and Thermal Properties of Thermo-Oxidative Aged SBS in Blends and Their Relations.

    Science.gov (United States)

    Xu, Xiong; Yu, Jianying; Xue, Lihui; Zhang, Canlin; Zha, Yagang; Gu, Yi

    2017-07-07

    Tri-block copolymer styrene-butadiene (SBS) is extensively applied in bituminous highway construction due to its high elasticity and excellent weather resistance. With the extension of time, tri-block structural SBS automatically degrades into bi-block structural SB- with some terminal oxygen-containing groups under the comprehensive effects of light, heat, oxygen, etc. In this paper, the effects of aging temperature, aging time and oxygen concentration on the molecular structure of thermo-oxidative aged SBS were mainly investigated using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), and the correlation between oxygen-containing groups and thermal properties (TG-DTG) was further discussed. The FTIR and XPS results show that rapid decomposition of SBS will occur with increments of aging temperature, aging time and oxygen concentration, and a large number of oxygen-containing groups such as -OH, C=O, -COOH, etc. will be formed during thermo-oxidative aging. In short-term aging, changes in aging temperature and oxygen concentration have a significant impact on the structural damage of SBS. However, in long-term aging, it has no further effect on the molecular structure of SBS or on increasing oxygen concentration. The TG and DTG results indicate that the concentration of substances with low molecular weight gradually increases with the improvement of the degree of aging of the SBS, while the initial decomposition rate increases at the beginning of thermal weightlessness and the decomposition rate slows down in comparison with neat SBS. From the relation between the XPS and TG results, it can be seen that the initial thermal stability of SBS rapidly reduces as the relative concentration of the oxygen-containing groups accumulates around 3%, while the maximum decomposition temperature slowly decreases when the relative concentration of the oxygen-containing groups is more than 3%, due to the difficult damage to strong bonds

  7. Investigation of Molecular Structure and Thermal Properties of Thermo-Oxidative Aged SBS in Blends and Their Relations

    Science.gov (United States)

    Xu, Xiong; Yu, Jianying; Xue, Lihui; Zhang, Canlin; Zha, Yagang; Gu, Yi

    2017-01-01

    Tri-block copolymer styrene–butadiene (SBS) is extensively applied in bituminous highway construction due to its high elasticity and excellent weather resistance. With the extension of time, tri-block structural SBS automatically degrades into bi-block structural SB- with some terminal oxygen-containing groups under the comprehensive effects of light, heat, oxygen, etc. In this paper, the effects of aging temperature, aging time and oxygen concentration on the molecular structure of thermo-oxidative aged SBS were mainly investigated using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), and the correlation between oxygen-containing groups and thermal properties (TG–DTG) was further discussed. The FTIR and XPS results show that rapid decomposition of SBS will occur with increments of aging temperature, aging time and oxygen concentration, and a large number of oxygen-containing groups such as –OH, C=O, –COOH, etc. will be formed during thermo-oxidative aging. In short-term aging, changes in aging temperature and oxygen concentration have a significant impact on the structural damage of SBS. However, in long-term aging, it has no further effect on the molecular structure of SBS or on increasing oxygen concentration. The TG and DTG results indicate that the concentration of substances with low molecular weight gradually increases with the improvement of the degree of aging of the SBS, while the initial decomposition rate increases at the beginning of thermal weightlessness and the decomposition rate slows down in comparison with neat SBS. From the relation between the XPS and TG results, it can be seen that the initial thermal stability of SBS rapidly reduces as the relative concentration of the oxygen-containing groups accumulates around 3%, while the maximum decomposition temperature slowly decreases when the relative concentration of the oxygen-containing groups is more than 3%, due to the difficult damage to strong

  8. Thermal analysis as an aid to forensics: Alkane melting and oxidative stability of wool

    International Nuclear Information System (INIS)

    Alan Riga, D.

    1998-01-01

    Interdisciplinary methods and thermal analytical techniques in particular are effective tools in aiding the identification and characterization of materials in question involved in civil or criminal law. Forensic material science uses systematic knowledge of the physical or material world gained through analysis, observation and experimentation. Thermal analytical data can be used to aid the legal system in interpreting technical variations in quite often a complex system.Calorimetry and thermal microscopic methods helped define a commercial product composed of alkanes that was involved in a major law suit. The solid-state structures of a number of normal alkanes have unique crystal structures. These alkanes melt and freeze below room temperature to more than 60C below zero. Mixtures of specific alkanes have attributes of pure chemicals. The X-ray diffraction structure of a mixture of alkanes is the same as a pure alkane, but the melting and freezing temperature are significantly lower than predicted. The jury ruled that the product containing n-alkanes had the appropriate melting characteristics. The thermal-physical properties made a commercial fluid truly unique and there was no advertising infringement according to the law and the jury trialA combination of thermogravimetry, differential thermal analysis, infrared spectroscopy and macrophotography were used to conduct an extensive modeling and analysis of physical evidence obtained in a mobile home fire and explosion. A person's death was allegedly linked to the misuse of a kerosene space heater. The thermal analytical techniques showed that external heating was the cause of the space heater's deformation, not a firing of the heater with gasoline and kerosene. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. The modeling and simulation of thermal based modified solid oxide fuel cell (SOFC for grid-connected systems

    Directory of Open Access Journals (Sweden)

    Ayetül Gelen

    2015-05-01

    Full Text Available This paper presents a thermal based modified dynamic model of a Solid Oxide Fuel Cell (SOFC for grid-connected systems. The proposed fuel cell model involves ohmic, activation and concentration voltage losses, thermal dynamics, methanol reformer, fuel utilization factor and power limiting module. A power conditioning unit (PCU, which consists of a DC-DC boost converter and a DC-AC voltage-source inverter (VSI, their controller, transformer and filter, is designed for grid-connected systems. The voltage-source inverter with six Insulated Gate Bipolar Transistor (IGBT switches inverts the DC voltage that comes from the converter into a sinusoidal voltage synchronized with the grid. The simulations and modeling of the system are developed on Matlab/Simulink environment. The performance of SOFC with converter is examined under step and random load conditions. The simulation results show that the designed boost converter for the proposed thermal based modified SOFC model has fairly followed different DC load variations. Finally, the AC bus of 400 Volt and 50 Hz is connected to a single-machine infinite bus (SMIB through a transmission line. The real and reactive power managements of the inverter are analyzed by an infinite bus system. Thus, the desired nominal values are properly obtained by means of the inverter controller.

  10. Excellent c-Si surface passivation by thermal atomic layer deposited aluminum oxide after industrial firing activation

    Science.gov (United States)

    Liao, B.; Stangl, R.; Ma, F.; Mueller, T.; Lin, F.; Aberle, A. G.; Bhatia, C. S.; Hoex, B.

    2013-09-01

    We demonstrate that by using a water (H2O)-based thermal atomic layer deposited (ALD) aluminum oxide (Al2O3) film, excellent surface passivation can be attained on planar low-resistivity silicon wafers. Effective carrier lifetime values of up to 12 ms and surface recombination velocities as low as 0.33 cm s-1 are achieved on float-zone wafers after a post-deposition thermal activation of the Al2O3 passivation layer. This post-deposition activation is achieved using an industrial high-temperature firing process which is commonly used for contact formation of standard screen-printed silicon solar cells. Neither a low-temperature post-deposition anneal nor a silicon nitride capping layer is required in this case. Deposition temperatures in the 100-400 °C range and peak firing temperatures of about 800 °C (set temperature) are investigated. Photoluminescence imaging shows that the surface passivation is laterally uniform. Corona charging and capacitance-voltage measurements reveal that the negative fixed charge density near the AlOx/c-Si interface increases from 1.4 × 1012 to 3.3 × 1012 cm-2 due to firing, while the midgap interface defect density reduces from 3.3 × 1011 to 0.8 × 1011 cm-2 eV-1. This work demonstrates that direct firing activation of thermal ALD Al2O3 is feasible, which could be beneficial for solar cell manufacturing.

  11. Investigation on Synthesis, Stability, and Thermal Conductivity Properties of Water-Based SnO2/Reduced Graphene Oxide Nanofluids

    Directory of Open Access Journals (Sweden)

    Xiaofen Yu

    2017-12-01

    Full Text Available With the rapid development of industry, heat removal and management is a major concern for any technology. Heat transfer plays a critically important role in many sectors of engineering; nowadays utilizing nanofluids is one of the relatively optimized techniques to enhance heat transfer. In the present work, a facile low-temperature solvothermal method was employed to fabricate the SnO2/reduced graphene oxide (rGO nanocomposite. X-ray diffraction (XRD, thermogravimetric analysis (TGA, X-ray photoelectron spectroscope (XPS, Raman spectroscopy, and transmission electron microscopy (TEM have been performed to characterize the SnO2/rGO nanocomposite. Numerous ultrasmall SnO2 nanoparticles with average diameters of 3–5 nm were anchored on the surface of rGO, which contain partial hydrophilic functional groups. Water-based SnO2/rGO nanofluids were prepared with various weight concentrations by using an ultrasonic probe without adding any surfactants. The zeta potential was measured to investigate the stability of the as-prepared nanofluid which exhibited great dispersion stability after quiescence for 60 days. A thermal properties analyzer was employed to measure thermal conductivity of water-based SnO2/rGO nanofluids, and the results showed that the enhancement of thermal conductivity could reach up to 31% at 60 °C under the mass fraction of 0.1 wt %, compared to deionized water.

  12. Investigation on Synthesis, Stability, and Thermal Conductivity Properties of Water-Based SnO2/Reduced Graphene Oxide Nanofluids

    Science.gov (United States)

    Yu, Xiaofen; Wu, Qibai; Zhang, Haiyan; Zeng, Guoxun; Li, Wenwu; Qian, Yannan; Li, Yang; Yang, Guoqiang; Chen, Muyu

    2017-01-01

    With the rapid development of industry, heat removal and management is a major concern for any technology. Heat transfer plays a critically important role in many sectors of engineering; nowadays utilizing nanofluids is one of the relatively optimized techniques to enhance heat transfer. In the present work, a facile low-temperature solvothermal method was employed to fabricate the SnO2/reduced graphene oxide (rGO) nanocomposite. X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscope (XPS), Raman spectroscopy, and transmission electron microscopy (TEM) have been performed to characterize the SnO2/rGO nanocomposite. Numerous ultrasmall SnO2 nanoparticles with average diameters of 3–5 nm were anchored on the surface of rGO, which contain partial hydrophilic functional groups. Water-based SnO2/rGO nanofluids were prepared with various weight concentrations by using an ultrasonic probe without adding any surfactants. The zeta potential was measured to investigate the stability of the as-prepared nanofluid which exhibited great dispersion stability after quiescence for 60 days. A thermal properties analyzer was employed to measure thermal conductivity of water-based SnO2/rGO nanofluids, and the results showed that the enhancement of thermal conductivity could reach up to 31% at 60 °C under the mass fraction of 0.1 wt %, compared to deionized water. PMID:29280972

  13. Enhanced mechanical, thermal and antimicrobial properties of poly(vinyl alcohol)/graphene oxide/starch/silver nanocomposites films.

    Science.gov (United States)

    Usman, Adil; Hussain, Zakir; Riaz, Asim; Khan, Ahmad Nawaz

    2016-11-20

    In the present work, synthesis of poly(vinyl alcohol)/graphene oxide/starch/silver (PVA/GO/Starch/Ag) nanocomposites films is reported. Such films have been characterized and investigated for their mechanical, thermal and antimicrobial properties. The exfoliation of GO in the PVA matrix occurs owing to the non-covalent interactions of the polymer chains of PVA and hydrophilic surface of the GO layers. Presence of GO in PVA and PVA/starch blends were found to enhance the tensile strength of the nanocomposites system. It was found that the thermal stability of PVA as well as PVA/starch blend systems increased by the incorporation of GO where strong physical bonding between GO layers and PVA/starch blends is assumed to cause thermal barrier effects. Antimicrobial properties of the prepared films were investigated against Escherichia coli and Staphylococcus aureus. Our results show enhanced antimicrobial properties of the prepared films where PVA-GO, PVA-Ag, PVA-GO-Ag and PVA-GO-Ag-Starch showed antimicrobial activity in ascending order. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon ( Salmo salar L.).

    Science.gov (United States)

    Knudsen, David; Jutfelt, Fredrik; Sundh, Henrik; Sundell, Kristina; Koppe, Wolfgang; Frøkiaer, Hanne

    2008-07-01

    Saponins are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels of added soya saponins, one diet containing 25% lupin kernel meal, two diets based on 25% lupin kernel meal with different levels of added soya saponins, and one diet containing 25% defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content was examined. Fish fed 25% defatted soyabean meal displayed severe enteritis, whereas fish fed 25% lupin kernel meal had normal intestinal morphology. The combination of soya saponins and fishmeal did not induce morphological changes but fish fed soya saponins in combination with lupin kernel meal displayed significant enteritis. Increased epithelial permeability was observed in fish fed 25% defatted soyabean meal and in fish fed soya saponin concentrate independent of the protein source in the feed. The study demonstrates that soya saponins, in combination with one or several unidentified components present in legumes, induce an inflammatory reaction in the distal intestine of Atlantic salmon. Soya saponins increase the intestinal epithelial permeability but do not, per se, induce enteritis.

  15. Effect of antioxidant tertiary butyl hydroquinone on the thermal and oxidative stability of sesame oil (sesamum indicum) by ultrasonic studies.

    Science.gov (United States)

    Prasad, N; Siddaramaiah, Basavarajaiah; Banu, Mujeeda

    2015-04-01

    The aim of the current investigation is to evaluate the efficiency of tertiary butyl hydroquinone (TBHQ) as an antioxidant in sesame oil (sesamum indicum) by density, viscosity and ultrasonic velocity. The effects of varying amounts of TBHQ on the oxidation stability of sesame oil have been investigated. The antioxidant incorporated sesame oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters used to assess the thermal degradation and oxidation properties of the oils include ultrasonic velocity, viscosity, density and peroxide value. The fatty acid compositions of the oils were measured by gas chromatography. Adiabatic compressibility, intermolecular free length, relaxation time and acoustic impedance have been calculated from experimental data. Viscosity, density and ultrasonic velocity change in control oil is from 3.6553 × 10(-2) to 11.1729 × 10(-2) Nsm(-2), 912.59 to 940.31 kg/m(3) and 1,421 to 1,452 m/s respectively and in sesame oil with 200 ppm TBHQ is from 3.6793 × 10(-2) to 6.4842 × 10(-2) Nsm(-2), 913.78 to 922.45 kg/m(3) and 1,421 to 1,431 m/s respectively for 16 h of heat treated oil. The ultrasonic results obtained have shown reduction in thermal degradation and improvement in oxidation stability of antioxidant loaded oil in comparison to base oil. Hence, it can be recommended that sesame oil with 200 ppm TBHQ can be used for frying without adverse effect on physical properties. The ultrasonic velocity can be used for assessment of stability of frying oil.

  16. Effect of antioxidant butylated hydroxyl anisole on the thermal or oxidative stability of sunflower oil (Helianthus Annuus) by ultrasonic.

    Science.gov (United States)

    Murari, Satish Kumar; Shwetha, M V

    2016-01-01

    The aim of the current investigation was to evaluate the efficiency of butylated hydroxyl anisole (BHA) as an antioxidant in sunflower oil (Helianthus Annuus). The oxidation stability of sunflower oil have been investigated by the effects of varying amounts of BHA. The antioxidant incorporated sunflower oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters used to assess the thermal degradation and oxidation properties of the oils include ultrasonic velocity, viscosity, density and peroxide value. The fatty acid compositions of the oils were measured by gas chromatography. Adiabatic compressibility, intermolecular free length, relaxation time and acoustic impedance have been calculated from experimental data. Viscosity, density and ultrasonic velocity change in control oil is from 3.72 × 10(-2) to 13.2 × 10(-2) Nsm - 2, 918 to 994 kg/m3 and 1412 to 1484 m/s respectively and in sunflower oil with 200 ppm BHA is from 3.88 × 10(-2) to 7.52 × 10(-2) Nsm - 2, 926 to 962 kg/m3 and 1418 to 1463 m/s respectively for 16 h of heat treated oil. The ultrasonic results obtained have shown reduction in thermal degradation and improvement in oxidation stability of antioxidant loaded oil in comparison to base oil. Hence, it can be recommended that sunflower oil with 200 ppm BHA can be used for frying without adverse effect on physical properties. The ultrasonic velocity can be used for assessment of stability of frying oil.

  17. Structural and thermal properties of ternary narrow-gap oxide semiconductor; wurtzite-derived β-CuGaO2.

    Science.gov (United States)

    Nagatani, Hiraku; Suzuki, Issei; Kita, Masao; Tanaka, Masahiko; Katsuya, Yoshio; Sakata, Osami; Miyoshi, Shogo; Yamaguchi, Shu; Omata, Takahisa

    2015-02-16

    The crystal structure of the wurtzite-derived β-CuGaO2 was refined by Rietveld analysis of high-resolution powder diffraction data obtained from synchrotron X-ray radiation. Its structural characteristics are discussed in comparison with the other I-III-VI2 and II-VI oxide semiconductors. The cation and oxygen tetrahedral distortions of the β-CuGaO2 from an ideal wurtzite structure are small. The direct band-gap nature of the β-CuGaO2, unlike β-Ag(Ga,Al)O2, was explained by small cation and oxygen tetrahedral distortions. In terms of the thermal stability, the β-CuGaO2 irreversibly transforms into delafossite α-CuGaO2 at >460 °C in an Ar atmosphere. The transformation enthalpy was approximately -32 kJ mol(-1), from differential scanning calorimetry. This value is close to the transformation enthalpy of CoO from the metastable zincblende form to the stable rock-salt form. The monovalent copper in β-CuGaO2 was oxidized to divalent copper in an oxygen atmosphere and transformed into a mixture of CuGa2O4 spinel and CuO at temperatures >350 °C. These thermal properties indicate that β-CuGaO2 is stable at ≤300 °C in both reducing and oxidizing atmospheres while in its metastable form. Consequently, this material could be of use in optoelectronic devices that do not exceed 300 °C.

  18. Surfactant controlled low-temperature thermal decomposition route to zinc oxide nanorods from zinc(II) acetylacetonate monohydrate

    Energy Technology Data Exchange (ETDEWEB)

    Purkayastha, Debraj Dhar; Sarma, Bedabrat; Bhattacharjee, Chira R., E-mail: crbhattacharjee@rediffmail.com

    2014-10-15

    Zinc oxide (ZnO) nanorods were synthesized via a low-temperature thermal decomposition of zinc(II) acetylacetonate monohydrate, [Zn(C{sub 5}H{sub 7}O{sub 2}){sub 2}].H{sub 2}O. A relatively inexpensive surfactant, octadecylamine (C{sub 18}H{sub 37}NH{sub 2}) served both as a reaction solvent and a capping agent during the synthesis of ZnO nanorods. The synthesized nanorods were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), FT-IR, UV–visible, and photoluminescence (PL) studies. The XRD spectrum furnished evidence for the hexagonal wurtzite structure of ZnO. TEM images revealed the material to be rod shaped having diameter 30 nm and length 200 nm. The HRTEM image showed that the lattice fringes between the two adjacent planes are 0.244 nm apart, which corresponds to the interplanar separation of the (1 0 1) plane of hexagonal ZnO. The electron diffraction (ED) pattern confirmed the single crystalline nature of the nanorods. The PL spectrum showed two UV emissions at 356 nm (∼3.48 eV) and 382 nm (∼3.25 eV). ZnO nanorods also showed very weak blue bands at 445, 453 and 470 nm. - Highlights: Low temperature thermal decomposition of zinc(II) acetylacetonate monohydrate gave zinc oxide nanorods. Powder XRD showed hexagonal wurtzite structure of ZnO having average diameter about 24 nm. TEM images revealed the material to be of rod shape having diameter 30 nm and length 200 nm. ZnO showed band gap luminescence at 356 nm, excitonic emission at 382 nm and defect related blue bands. The synthesis is simple and can act as a paradigm for obtaining various metal oxide nanomaterials.

  19. Soya oil-based shampoo superior to 0.5% permethrin lotion for head louse infestation

    Directory of Open Access Journals (Sweden)

    Nazma A Burgess

    2011-03-01

    Full Text Available Ian F Burgess1, Katrina Kay1,2, Nazma A Burgess1, Elizabeth R Brunton11Medical Entomology Centre, Insect Research and Development Limited, Cambridge, 2Leeds Primary Care Trust, Leeds, UKBackground: This was a randomized, assessor-blind, controlled comparison of a soya oil-based medical device shampoo with a medicinal permethrin lotion in an alcohol vehicle for treatment of head louse infestation to generate data suitable for a regulatory submission to achieve reimbursable status for the shampoo product.Methods: We treated 91 children and adults, divided between two sites, on two occasions 9 days apart. Participants washed their hair and towel-dried it before treatment. The shampoo was used twice for 30 minutes each time. The lotion was used for 30 minutes followed by rinsing. Assessments were made by dry detection combing on days 2, 9, 11, and 14 after the first treatment. According to present knowledge, this combing technique does not influence the overall head louse populations or outcome of treatment.Results: The soya oil shampoo was significantly (P < 0.01 more effective than the lotion for both intention to treat (62.2% versus 34.8% successful treatment and per-protocol (74.3% versus 36.8% success groups. Post-treatment assessments showed the necessity for repeat treatment, but that a 9-day interval was too long because if eggs hatched after the first treatment, the lice could grow old enough to lay eggs before the second treatment.Conclusion: The soya oil-based shampoo was more effective than the permethrin lotion, more cosmetically acceptable, and less irritant.Keywords: pediculosis, medical device, medicinal product, insecticide, vegetable oil

  20. Producción y valor nutricional del forraje de soya en condiciones tropicales adversas

    Directory of Open Access Journals (Sweden)

    Carlos Tobía

    2004-01-01

    Full Text Available Una parcela de soya (Glycine max L. Merr. var. ‘CIGRAS-06’ de 2,4 ha, cultivada en condiciones de alta precipitación y temperatura y en un suelo ácido (pH 4,78 con baja fertilidad, en La Virgen de Sarapiquí, produjo un promedio de 4,8 t ha-1 de materia seca, cuando la planta entera se cosechó para forraje en el estado de desarrollo R6 (semillas llenas. Esta productividad es baja, en comparación con la obtenida en Guanacaste y San Carlos, donde las condiciones de clima y suelo fueron favorables para la producción de esta especie. La composición química de la planta entera fue de 20,2% de proteína, 6,7% de grasa, 5,5% de cenizas, 42,2% de fibra detergente neutro y 25,4% de carbohidratos no fibrosos. La proporción del peso seco de las hojas: vainas+semillas:tallos+pecíolos de las plantas fue de 24:39:37, respectivamente. Un análisis económico de los resultados señala que la producción de forraje y de ensilaje tal como fue ofrecido tuvo un costo de 0,02 y 0,03 US $ kg-1, respectivamente. Se pone en evidencia que aún en las condiciones adversas de clima y suelo donde tuvo lugar esta investigación, es posible aprovechar las cualidades nutricionales de la soya en la alimentación del ganado lechero, a un costo relativamente bajo y sin los inconvenientes y la alta inversión en maquinaria y equipo que representa la producción de soya para semilla en el trópico húmedo.