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Sample records for alumina capillaries mcp

  1. Ion guiding in alumina capillaries

    DEFF Research Database (Denmark)

    Juhász, Z.; Sulik, B.; Biri, S.;

    2009-01-01

    Transmission of a few keV impact energy Ne ions through capillaries in anodic alumina membranes has been studied with different ion counting methods using an energy dispersive electrostatic spectrometer, a multichannel plate (MCP) array and sensitive current-measurement. In the present work, we...

  2. Lifetime of MCP-PMTs

    Science.gov (United States)

    Lehmann, A.; Britting, A.; Eyrich, W.; Pfaffinger, M.; Uhlig, F.; Belias, A.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Kalicy, G.; Krebs, M.; Lehmann, D.; Nerling, F.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Zühlsdorf, M.; Düren, M.; Etzelmüller, E.; Föhl, K.; Hayrapetyan, A.; Kröck, B.; Merle, O.; Rieke, J.; Schmidt, M.; Cowie, E.; Keri, T.; Achenbach, P.; Cardinali, M.; Hoek, M.; Lauth, W.; Schlimme, S.; Sfienti, C.; Thiel, M.

    2016-05-01

    The hadron identification in the PANDA experiment at FAIR will be done with DIRC detectors. Because of design and space reasons the sensors of the DIRCs have to be placed inside the strong magnetic field of the solenoid. As the favored photon sensors microchannel-plate photomultipliers (MCP-PMTs) were identified. However, these devices showed serious aging problems until very recently, which manifest themselves by a fast degrading quantum efficiency (QE) of the photo cathode (PC). This is mainly due to feedback ions from the residual gas. In this paper we discuss the recently accomplished huge improvements in the lifetime of MCP-PMTs. With innovative countermeasures applied to the MCP-PMTs in the attempt to reduce the aging effects the manufacturers were able to increase the lifetime of MCP-PMT prototypes by almost two orders of magnitude compared to the former commercially available devices. Our group has studied the aging of MCP-PMTs for more than four years by simultaneously illuminating different types of lifetime-enhanced MCP-PMTs at the same photon rate. Gain, dark count rate, and QE as a function of the wavelength and the PC surface were measured in regular time intervals and studied in dependence of the integrated anode charge. We observe that MCP-PMTs treated with an atomic layer deposition (ALD) technique are by far the best devices available now. A lifetime of up to 10 C/cm2 integrated anode charge was reached with these sensors. This is sufficient for both PANDA DIRCs.

  3. Photocathode aging in MCP PMT

    International Nuclear Information System (INIS)

    We study aging of alkali-antimonide photocathodes in the microchannel plate photomultiplier tubes (MCP PMT) manufactured in Novosibirsk by ''Ekran FEP'' company. Such PMTs are used in the particle identification systems of KEDR, SND and CMD-3 experiments carried out at e+e− colliders VEPP-4M and VEPP-2000 in the Budker Institute of Nuclear Physics. The quantum efficiency (QE) degradation of a PMT equipped with MCP Chevron has been measured at different photon counting rates from 4⋅107 to 6⋅1010 s−1cm−2. It is found that the QE decrease is proportional to the charge extracted from the MCP nearest to the photocathode rather than to the output charge. The comparison of different types of alkali-antimonide photocathodes has shown that the treatment of photocathode with vapors of cesium and antimony can dramatically reduce the photocathode aging rate. The photocathode lifetime of the best MCP PMT sample has been measured at the photon counting rate of 107 cm−2s−1 and the initial gain of 106. The peak quantum efficiency degraded by 20% after accumulation of 3.3 C/cm2 anode charge.

  4. The MCP-based vertex detector

    CERN Document Server

    Gevorkov, L G; CERN. Geneva; Laptev, V D; Patarakin, O O; Valiev, F F

    1992-01-01

    We discuss the possible application of large area microchannel plates (MCPs) as a basic Abstract: element of a vertex detector unit. Two types of basic modules : (MCP + Delay Line) and (MCP + Microstrips) are suggested. The proposal exploits unique MCPàs features i.e. fine granularity, high intrinsic gain, high counting rates, good performance in the presence of a magnetic field.

  5. Compact MCP assemblies for mass spectrometers

    International Nuclear Information System (INIS)

    We have developed compact microchannel plate (MCP) assemblies which have a high gain, good pulse height resolution and a fast response for MS applications. In this paper, these new assemblies are described referring to their structures, functions and characteristics. (orig.)

  6. Transport properties of alumina nanofluids

    International Nuclear Information System (INIS)

    volumetric concentrations. A 3457.1% increase in the electrical conductivity was measured for a small 1.44% volumetric concentration of alumina nanoparticles in water. The highest value of electrical conductivity, 314 μS cm-1, was recorded for a volumetric concentration of 8.47%. In the determination of the kinematic viscosity of alumina nanofluid, a standard kinematic viscometer with constant temperature bath was used. Calibrated capillary viscometers were used to measure flow under gravity at precisely controlled temperatures. The capillary viscometers were calibrated with de-ionized water at different temperatures, and the resulting kinematic viscosity values were found to be within 3% of the standard published values. An increase of 35.5% in the kinematic viscosity was observed for an 8.47% volumetric concentration of alumina nanoparticles in water. The maximum kinematic viscosity of alumina nanofluid, 2.901 42 mm2 s-1, was obtained at 0 deg. C for an 8.47% volumetric concentration of alumina nanoparticles. The experimental results of the present work will help researchers arrive at better theoretical models

  7. Conservação da qualidade de caqui 'Fuyu' em ambiente refrigerado pela combinação de 1-MCP e atmosfera modificada Quality maintenance of 'Fuyu' persimmon in cold storage by combining 1-MCP and modified atmosphere

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Argenta

    2009-06-01

    Full Text Available O presente estudo analisou os efeitos do inibidor da ação do etileno 1-MCP (1-metilciclopropeno, da AM (atmosfera modificada e do oxidante de etileno KMnO4 (permanganato de potássio sobre a qualidade de caqui 'Fuyu' após a armazenagem refrigerada. Os fatores 1-MCP, AM e KMnO4 foram combinados de quatro maneiras, correspondendo aos seguintes tratamentos: T1 Controle + AM + KMnO4;T2 1-MCP + AM + KMnO4; T3 1-MCP + AM, e T4 1-MCP + AA (AA=atmosfera do ar. Frutos maduro-firmes com coloração da casca predominantemente amarela foram colhidos em sete pomares comerciais no nordeste do Estado do Rio Grande do Sul. Parte dos frutos foi exposta a 0.3 µL L-1 de 1-MCP por 12 h em 24 h após a colheita. A seguir, os frutos foram armazenados sob AA ou sob AM induzida por bolsas de polietileno (0,04 mm de espessura, por 20; 40; 60 ou 80 dias a -0,1±0,8ºC. Dois sachês contendo 8,5 g de Alumina-KMnO4foram adicionados em cada uma das bolsas de polietileno dos tratamentos um e dois, antes de elas serem vedadas. Os frutos de cada período de armazenagem refrigerada foram analisados após 0; 3; 6 ou 9 dias de prateleira sob AA a 22±1ºC. O tratamento 1-MCP retardou o amolecimento da polpa, mas não afetou consistentemente o desenvolvimento de 'estrias' e manchas pretas na superfície dos frutos armazenados sob AM contendo KMnO4. A incidência de 'estrias' e manchas pretas em frutos tratados com 1-MCP e armazenados sob AM foi significativamente menor que a de frutos tratados com 1-MCP e armazenados sob AA. Houve efeitos aditivos do 1-MCP e AM na conservação da firmeza e na redução de danos por frio manifestados pela formação de textura gel-firme e manchas translúcidas na casca. O uso de KMnO4 não aumentou a conservação da qualidade dos frutos quando tratados com 1-MCP e armazenados sob AM. O desenvolvimento dos distúrbios da epiderme dependeu do pomar e de períodos de armazenagem e prateleira. No entanto, os benefícios da combinação de 1-MCP e

  8. Soft X-Ray Emission Analysis Of A Pulsed Capillary Discharge Operated In Nitrogen

    Science.gov (United States)

    Valdivia, M. P.; Valenzuela, J. C.; Wyndham, E. S.; Favre, M.; Chuaqui, H.; Bhuyan, H.

    2014-05-01

    We present results from a pulsed capillary ns discharge source, operated in Nitrogen and N/He mixtures, in an alumina capillary 2.1mm long with outer diameter of 6.3mm and inner diameter of 1.6mm. The electrical energy stored is 0.5J with peak current of 6kA. Fast charging from an IGBT based pulsed power circuit allows operation at 35-600 Hz with voltages in the range of 18-24kV. Characteristic time-integrated N/He spectra were recorded and analyzed for values of 20-200 Å, with clear evidence of He-like Nitrogen emission at 28.8Å, which represents a possible source for water window soft x-ray microscopy. Filtered diode measurements reveal the influence of axial electron beams, generated by hollow cathode dynamics, on the x-ray emission in the range of 300-450 eV. We discuss optimal voltage applied and pressure conditions for soft x-ray generation. Time-integrated MCP images of a filtered slit-wire system delivered clear evidence of full wall detachment with ~500μm in radial size for the entire emission range and ~200μm for the emission in the 300-450 eV range.

  9. MCP-based Photodetectors for Cryogenic Applications

    CERN Document Server

    Dharmapalan, Ranjan; Byrum, Karen; Demarteau, Marcel; Elam, Jeffrey; May, Edward; Wagner, Robert; Walters, Dean; Xia, Lei; Xie, Junqi; Zhao, Huyue; Wang, J

    2016-01-01

    The Argonne MCP-based photo detector is an offshoot of the Large Area Pico-second Photo Detector (LAPPD) project, wherein 6 cm x 6 cm sized detectors are made at Argonne National Laboratory. We have successfully built and tested our first detectors for pico-second timing and few mm spatial resolution. We discuss our efforts to customize these detectors to operate in a cryogenic environment. Initial plans aim to operate in liquid argon. We are also exploring ways to mitigate wave length shifting requirements and also developing bare-MCP photodetectors to operate in a gaseous cryogenic environment.

  10. Contribution of aluminas and aluminosilicates to the formation of PCDD/Fs on fly ashes.

    Science.gov (United States)

    Potter, Phillip M; Dellinger, Barry; Lomnicki, Slawomir M

    2016-02-01

    Chlorinated aromatics undergo surface-mediated reactions with metal oxides to form Environmentally Persistent Free Radicals (EPFRs) which can further react to produce polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Previous work using laboratory-made fly ash surrogates composed of transition metal oxides deposited on silica powder has confirmed their ability to mimic fly ash in the production of PCDD/Fs. However, little is known about the propensity of aluminas and aluminosilicates, other components of fly ash, to form PCDD/Fs. A fly ash sample containing both alumina and mullite, an aluminosilicate, was tested for PCDD/F formation ability and compared to PCDD/F yields from the thermal degradation of 2-monochlorophenol (2-MCP) precursor over γ-alumina, α-alumina, and mullite. A packed-bed flow reactor was used to investigate the thermal degradation of 2-MCP over the various catalysts at 200-600 °C. Fly ash gave similar PCDD/F yields to surrogates made with similar transition metal content. γ-alumina, which is thermodynamically unfavorable, was very catalytically active and gave low PCDD/F yields despite a high destruction of 2-MCP. Mullite and α-alumina, the thermodynamically favorable form of alumina, yielded higher concentrations of dioxins and products with a higher degree of chlorine substitution than γ-alumina. The data suggest that certain aluminas and aluminosilicates, commonly found in fly ash, are active catalytic surfaces in the formation of PCDD/Fs in the post-flame cool zones of combustion systems and should be considered as additional catalytic surfaces active in the process. PMID:26615490

  11. Structural analysis of impeller for SMART MCP

    International Nuclear Information System (INIS)

    The structural integrity of the MCP impeller is important for the safe and reliable operation of the SMART, since the impeller is operated for long period inside the reactor under high pressure and high temperature. In this study, an analysis model to evaluate the structural integrity of axial pump impeller has been developed and the stress state in the impeller of SMART MCP has been calculated for the applied centrifugal and hydraulic forces. The structural integrity of the impeller has been demonstrated by comparing the analysis results with the allowable stresses. The modal analysis of the impeller has been also performed to investigate the possibility of the resonances of the impeller blades with the rotational frequencies. As a means to reduce the time required for the analysis, a cyclic symmetric analysis model with optimum boundary conditions is proposed by comparing the results from full model analyses

  12. Estimation of thermal shock resistance of fine porous alumina by infrared radiation heating method

    OpenAIRE

    Iwamoto, Yuji; Honda, Sawao; Ogihara, Yuki; Kishi, Tsunego; イワモト, ユウジ; ホンダ, サワオ; 岩本, 雄二; 本多, 沢雄

    2009-01-01

    The thermal shock resistance of α-alumina porous capillary, the support material for hydrogen-permselective microporous ceramic membrane was studied. To study the effect of porosity on the thermal shock resistance systematically, porous alumina with different porosities was fabricated, and the thermal shock resistance of the fabricated samples as well as the porous capillary was estimated by the infrared radiation heating method. The mechanical and thermal properties concerned to the thermal ...

  13. Novel electronics for MCP imaging detectors

    International Nuclear Information System (INIS)

    We describe novel electronics for processing signals from a microchannel plate detector using a resistive anode readout. High sampling-rate (MHz) Analogue-to-Digital Converters (ADCs) coupled to a Digital Signal Processor (DSP) combine to offer high spatial resolution (70μm), low noise (0.1countcm-1s-1) imaging over a large (93mmx93mm) imaging area.These new low-cost electronics form an integral part of a MCP-based system for digital autoradiography designed to image radiolabelled thin tissue slices and 1- and 2-D electrophoresis gels

  14. Single ion counting with a MCP (microchannel plate) detector

    Energy Technology Data Exchange (ETDEWEB)

    Tawara, Hiroko; Sasaki, Shinichi; Miyajima, Mitsuhiro [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan); Shibamura, Eido

    1996-07-01

    In this study, a single-ion-counting method using alpha-particle-impact ionization of Ar atoms is demonstrated and the preliminary {epsilon}{sub mcp} for Ar ions with incident energies of 3 to 4.7 keV is determined. The single-ion counting by the MCP is aimed to be performed under experimental conditions as follows: (1) A signal from the MCP is reasonably identified as incidence of single Ar-ion. (2) The counting rate of Ar ions is less than 1 s{sup -1}. (3) The incident Ar ions are not focused on a small part of an active area of the MCP, namely, {epsilon}{sub mcp} is determined with respect to the whole active area of the MCP. So far, any absolute detection efficiency has not been reported under these conditions. (J.P.N.)

  15. Lifetime-issues of MCP-PMTs

    International Nuclear Information System (INIS)

    Cherenkov detectors of the DIRC principle will be used at the P-bar ANDA experiment at FAIR. Attractive photo sensor candidates for these devices are micro-channel plate (MCP) photomultipliers (PMT). The reasons are their excellent time resolution and their usability inside magnetic fields, although their lifetime is problematic. Various types were investigated. This paper will concentrate on the performance of the Photonis XP85112 and especially its lifetime behavior. For this MCP-PMT a time resolution of 33ps (σ) was measured and it is stable up to photon rates of about 2 MHz/cm2. The peak quantum efficiency (QE) was determined to 24%. Before the actual lifetime measurement several studies were performed, such as scanning the surface of the detector to get the geometrical detector response function. Additionally the gain and time resolution were investigated in a magnetic field up to 2T. Afterwards the lifetime measurements were done up to an integrated charge of 305 mC/cm2, i.e. the collected charge was 1-5 mC/cm2 per day. The gain and QE were determined in irregular intervals of 1-3 days. Also QE scans as a function of the position at the photo cathode were done every 2-3 weeks.

  16. Bauxite and alumina

    Science.gov (United States)

    Bray, E.L.

    2009-01-01

    The article provides information on bauxite and alumina mining. U.S. states like Alabama, Arkansas and Georgia produced small amounts of bauxite and bauxitic clays for nonmetallurgical uses. Total metallurgical-grade bauxite imports in 2008 is cited. The leading suppliers of bauxite to the U.S. are Jamaica, Guinea and Brazil. The estimated domestic production of alumina in 2008 is mentioned. It also discusses consumption and prices of both bauxite and alumina.

  17. Porous Alumina Films with Width-Controllable Alumina Stripes

    Directory of Open Access Journals (Sweden)

    Huang Shi-Ming

    2010-01-01

    Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  18. Porous Alumina Films with Width-Controllable Alumina Stripes

    OpenAIRE

    Huang Shi-Ming; Pu Lin; Shi Yi; Huang Kai; Wu Zhi-Ming; Ji Li; Kang Jun-Yong

    2010-01-01

    Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure o...

  19. Microporous alumina ceramic membranes

    Science.gov (United States)

    Anderson, Marc A.; Sheng, Guangyao

    1993-01-01

    Several methods are disclosed for the preparation microporous alumina ceramic membranes. For the first time, porous alumina membranes are made which have mean pore sizes less than 100 Angstroms and substantially no pores larger than that size. The methods are based on improved sol-gel techniques.

  20. Reuse of activated alumina

    Energy Technology Data Exchange (ETDEWEB)

    Hobensack, J.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Activated alumina is used as a trapping media to remove trace quantities of UF{sub 6} from process vent streams. The current uranium recovery method employs concentrated nitric acid which destroys the alumina pellets and forms a sludge which is a storage and disposal problem. A recently developed technique using a distilled water rinse followed by three dilute acid rinses removes on average 97% of the uranium, and leaves the pellets intact with crush strength and surface area values comparable with new material. Trapping tests confirm the effectiveness of the recycled alumina as UF{sub 6} trapping media.

  1. Capillary electrophoresis

    International Nuclear Information System (INIS)

    After a short historical introduction, the different modes of separation in capillary electrophoresis are explained and illustrated by practical examples. In addition, the most important parameters that can be used to optimize the selectivity of the separation, are discussed. (author) 27 refs.; 8 figs

  2. Status of the Timepix MCP-HPD development

    CERN Document Server

    Tick, T; Michel, T; O'Shea, V; Plackett, R; Pospisil, S; Vallerga, J; Visser, J

    2010-01-01

    This paper describes the design of a high-speed, single-photon sensitive, Hybrid Photon Detector (HPD). The detector consists of a vacuum tube, containing a Micro Channel Plate (MCP) and 4 CMOS pixel readout chips, sealed with a transparent optical input window with a photocathode. The design described here utilizes currently available technologies, specifically the Timepix readout chips and the Photonis Planacon MCP-PMT vacuum tubes. The aim of the project is to demonstrate the feasibility of a 4-side buttable square MCP-HPD with high packing fraction sensitive area. Presented here is the mechanical and thermal design of the prototype detector

  3. Status of the Timepix MCP-HPD development

    International Nuclear Information System (INIS)

    This paper describes the design of a high-speed, single-photon sensitive, Hybrid Photon Detector (HPD). The detector consists of a vacuum tube, containing a Micro Channel Plate (MCP) and 4 CMOS pixel readout chips, sealed with a transparent optical input window with a photocathode. The design described here utilizes currently available technologies, specifically the Timepix readout chips and the Photonis Planacon MCP-PMT vacuum tubes. The aim of the project is to demonstrate the feasibility of a 4-side buttable square MCP-HPD with high packing fraction sensitive area. Presented here is the mechanical and thermal design of the prototype detector.

  4. MCP-PMT development for Belle-II TOP counter

    Science.gov (United States)

    Inami, K.

    We have developed a multiple-anode square-shape MCP-PMT for the Belle-II Time-Of-Propagation (TOP) counter. This detector is a hybrid cherenkov ring imaging and timing detector for particle identification in the barrel region of the upgraded detector. The Belle-II experiment will operate at high event rates and needs to withstand the correspondingly high background environment. MCP-PMT's have demonstrated excellent single photon timing resolution. However, the lifetime of photocathode is a known issue. Recently, we successfully improved the lifetime of a square-shape MCP-PMT by a factor of about 10, which is adequate for estimates of the nominal Belle-II background rates in the TOP counter. We have also developed a new MCP-PMT with Hamamatsu photonics, that adopts a super bialkali photocathode. Currently a peak quantum effciency of 28% for 400 nm photons has been achieved.

  5. Kaiser Permanente Medical Care Programs (KP-MCP)

    Science.gov (United States)

    The Division of Research within KP-MCP conducts, publishes, and disseminates high-quality epidemiologic and health services research to improve the health and medical care of Kaiser Permanente members and the society at large.

  6. New adsorbent, silver-alumina for radioactive iodine filter

    International Nuclear Information System (INIS)

    Silver-alumina adsorbent has been developed for the iodine filter installed in the off-gas treatment system of a radioactive waste tank vent. In order to improve the removal efficiency under a highly humid atmosphere and to reduce susceptibility to contaminants in the air, the optimum average pore size of alumina was determined to be about 600 A when the impregnated silver compound was silver nitrate. The holding capability of impregnated silver was also improved by developing a double pore structure alumina. The effects of chemical forms and contaminants on the removal efficiency were explained by an ionic reaction mechanism at high relative humidity, which involves water vapor adsorption in micropores by capillary condensation followed by formation of a silver iodide compound

  7. CCL2/MCP-1 modulation of microglial activation and proliferation

    Directory of Open Access Journals (Sweden)

    Garcia-Bueno Borja

    2011-07-01

    Full Text Available Abstract Background Monocyte chemoattractant protein (CCL2/MCP-1 is a chemokine that attracts cells involved in the immune/inflammatory response. As microglia are one of the main cell types sustaining inflammation in brain, we proposed here to analyze the direct effects of MCP-1 on cultured primary microglia. Methods Primary microglia and neuronal cultures were obtained from neonatal and embryonic Wistar rats, respectively. Microglia were incubated with different concentrations of recombinant MCP-1 and LPS. Cell proliferation was quantified by measuring incorporation of bromodeoxyuridine (BrdU. Nitrite accumulation was measured using the Griess assay. The expression and synthesis of different proteins was measured by RT-PCR and ELISA. Cell death was quantified by measuring release of LDH into the culture medium. Results MCP-1 treatment (50 ng/ml, 24 h did not induce morphological changes in microglial cultures. Protein and mRNA levels of different cytokines were measured, showing that MCP-1 was not able to induce proinflammatory cytokines (IL-1β, IL6, MIP-1α, either by itself or in combination with LPS. A similar lack of effect was observed when measuring inducible nitric oxide synthase (NOS2 expression or accumulation of nitrites in the culture media as a different indicator of microglial activation. MCP-1 was also unable to alter the expression of different trophic factors that were reduced by LPS treatment. In order to explore the possible release of other products by microglia and their potential neurotoxicity, neurons were co-cultured with microglia: no death of neurons could be detected when treated with MCP-1. However, the presence of MCP-1 induced proliferation of microglia, an effect opposite to that observed with LPS. Conclusion These data indicate that, while causing migration and proliferation of microglia, MCP-1 does not appear to directly activate an inflammatory response in this cell type, and therefore, other factors may be

  8. Optical emission spectroscopy observations of fast pulsed capillary discharge plasmas

    Science.gov (United States)

    Avaria, G.; Ruiz, M.; Guzmán, F.; Favre, M.; Wyndham, E. S.; Chuaqui, H.; Bhuyan, H.

    2014-05-01

    We present time resolved optical emission spectroscopic (OES) observations of a low energy, pulsed capillary discharage (PCD). The optical emission from the capillary plasma and plasma jets emitted from the capillary volume was recorded with with a SpectraPro 275 spectrograph, fitted with a MCP gated OMA system, with 15 ns time resolution. The discharge was operated with different gases, including argon, nitrogen, hydrogen and methane, in a repetitive pulsed discharge mode at 10-50 Hz, with, 10-12 kV pulses applied at the cathode side. The time evolution of the electron density was measured using Stark broadening of the Hβ line. Several features of the capillary plasma dynamics, such as ionization growth, wall effects and plasma jet evolution, are inferred from the time evolution of the optical emission.

  9. Regulation of MCP-1 chemokine transcription by p53

    Directory of Open Access Journals (Sweden)

    Wasylyk Bohdan

    2010-04-01

    Full Text Available Abstract Background Our previous studies showed that the expression of the monocyte-chemoattractant protein (MCP-1, a chemokine, which triggers the infiltration and activation of cells of the monocyte-macrophage lineage, is abrogated in human papillomavirus (HPV-positive premalignant and malignant cells. In silico analysis of the MCP-1 upstream region proposed a putative p53 binding side about 2.5 kb upstream of the transcriptional start. The aim of this study is to monitor a physiological role of p53 in this process. Results The proposed p53 binding side could be confirmed in vitro by electrophoretic-mobility-shift assays and in vivo by chromatin immunoprecipitation. Moreover, the availability of p53 is apparently important for chemokine regulation, since TNF-α can induce MCP-1 only in human keratinocytes expressing the viral oncoprotein E7, but not in HPV16 E6 positive cells, where p53 becomes degraded. A general physiological role of p53 in MCP-1 regulation was further substantiated in HPV-negative cells harboring a temperature-sensitive mutant of p53 and in Li-Fraumeni cells, carrying a germ-line mutation of p53. In both cases, non-functional p53 leads to diminished MCP-1 transcription upon TNF-α treatment. In addition, siRNA directed against p53 decreased MCP-1 transcription after TNF-α addition, directly confirming a crosstalk between p53 and MCP-1. Conclusion These data support the concept that p53 inactivation during carcinogenesis also affects immune surveillance by interfering with chemokine expression and in turn communication with cells of the immunological compartment.

  10. Alumina Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-02-01

    The Alumina Technology Roadmap outlines a comprehensive long-term research and development plan that defines the industry's collective future and establishes a clear pathway forward. It emphasizes twelve high-priority R&D areas deemed most significant in addressing the strategic goals.

  11. Solid Lubricant For Alumina

    Science.gov (United States)

    Dellacorte, Christopher; Pepper, Stephen V.; Honecy, Frank S.

    1993-01-01

    Outer layer of silver lubricates, while intermediate layer of titanium ensures adhesion. Lubricating outer films of silver deposited on thin intermediate films of titanium on alumina substrates found to reduce sliding friction and wear. Films provide effective lubrication for ceramic seals, bearings, and other hot sliding components in advanced high-temperature engines.

  12. Resolution changes of MCP-PMTs in magnetic fields

    Science.gov (United States)

    Rieke, J.; Belias, A.; Dzhygadlo, R.; Gerhardt, A.; Götzen, K.; Kalicy, G.; Krebs, M.; Lehmann, D.; Nerling, F.; Patsyuk, M.; Peters, K.; Schepers, G.; Schmitt, L.; Schwarz, C.; Schwiening, J.; Traxler, M.; Zühlsdorf, M.; Britting, A.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Düren, M.; Etzelmüller, E.; Föhl, K.; Hayrapetyan, A.; Kröck, B.; Merle, O.; Rieke, J.; Schmidt, M.; Cowie, E.; Keri, T.; Achenbach, P.; Cardinali, M.; Hoek, M.; Lauth, W.; Schlimme, S.; Sfienti, C.; Thiel, M.

    2016-05-01

    Micro-channel plate photomultiplier tubes (MCP-PMTs) are chosen in many applications that have to cope with strong magnetic fields. The DIRC detectors of the PANDA experiment plan to employ them as they show excellent timing characteristics, radiation hardness, relatively low dark count rates and sufficient lifetime. This article mainly focuses on the performance of the position reconstruction of detected photons. Two different MCP-PMTs with segmented anode geometries have been tested in magnetic fields of different strengths. The variation of their performance has been studied. The measurements show improved position resolution and image shifts with increasing magnetic field strength.

  13. MCP-based detector some results and perspectives

    CERN Document Server

    Patarakin, O O; Strepetov, A N; Turbin, E V; Sinitsin, V I; Kartamushev, A A

    1997-01-01

    The timing resolution of photomultiplier tubes (PMT) based on shevron-type microchannel plates (MCP) has been studied inmagnetic fields. The same timingresolution with and without a longitudinal magnetic field up to 2.0 kGwas obtained as = 85 ± 2 ps. It is shown that an increase of timing resolution in this magnetic field does not exceed25 ps (upper limit). The timing resolution of = 31 ± 2 pswas obtained for narrow (10resolution) amplitude spectrumfrom Corone discharge. The counting rate of MCP-based detector was studied in function of the direction of the magnetic field.The spatial and timing resolution for the MCP-based PMT were obtained using laser pulses as well. With laser pulses of 0.3 ns a timing resolution of ≅ 450 ps was obtained. Taking into account the amplitude correction narrows to 140 ps. Using 100 fs-laser with the standard constant fractiondiscriminator gives a timing resolution from 20 to 40 ps depending on the read-out MCP region.The perspectives of using...

  14. Nanoindentation of shock deformed alumina

    International Nuclear Information System (INIS)

    In the current study, the experimental results on the nanoindentation response of both as prepared and shock recovered alumina of 10 μm grain size and identical processing history are presented and analyzed. The shock recovery experiments were deliberately conducted with gas gun arrangements at shock pressures much above the Hugoniot Elastic Limit (HEL) of alumina. The nanoindentation experiments were conducted at 10-1000 mN load with a Berkovich indenter. The nanohardness and Young's modulus value of shock recovered alumina were always lower than those of the as prepared alumina samples. Subsequently, the detailed characterizations of the shock recovered alumina samples by X-ray diffraction, scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were utilized to understand the reasons behind the drop in nanohardness and Young's modulus of shock recovered alumina samples.

  15. High Temperature Stability of Potassium Beta Alumina

    Science.gov (United States)

    Williams, R. M.; Kisor, A.; Ryan, M. A.

    1996-01-01

    None. From Objectives section: Evaluate the stability of potassium beta alumina under potassium AMTEC operating conditions. Evaluate the stability regime in which potassium beta alumina can be fabricated.

  16. Effects of 1-MCP on Post-Harvest Physiology of Tomato

    Institute of Scientific and Technical Information of China (English)

    SUN Xi-sheng; WANG Zhi-hua; LI Zhi-qiang; ZHANG Zhi-yun; WANG Wen-hui

    2003-01-01

    Tomato (Lycopersicon esculentum cv. 402) was used to investigate the effects of 1-MCP (1-methylcyclopropene) treatment on ethylene production, respiration, vitamin C, chlorophyll, titratable acid,change of fruit color and rot. The results indicated that 1-MCP strongly inhibited ethylene production and respiration of tomato at very low concentration, delayed the incidence of climacteric peak of ethylene production and respiration. 1-MCP also delayed the decrease of vitamin C, chlorophyll and titratable acid during shelf life and storage significantly. Shelf and storage life of fruit treated with 1-MCP were extended at least 10 days at ambient (20 - 22℃ ) and 15 days at storage (9 - 11℃ ) temperature, respectively. Efficacy of 1-MCP on shelf and storage life was improved by increasing its concentration. After treatment of 1-MCP, rots were markedly lower than that of untreated fruit. 1-MCP treatment delayed the fruit color change.

  17. MCP-1 deficiency causes altered inflammation with impaired skeletal muscle regeneration.

    Science.gov (United States)

    Shireman, Paula K; Contreras-Shannon, Verónica; Ochoa, Oscar; Karia, Bijal P; Michalek, Joel E; McManus, Linda M

    2007-03-01

    We examined the role of MCP-1, a potent chemotactic and activating factor for macrophages, in perfusion, inflammation, and skeletal muscle regeneration post-ischemic injury. MCP-1-/- or C57Bl/6J control mice [wild-type (WT)] underwent femoral artery excision (FAE). Muscles were collected for histology, assessment of tissue chemokines, and activity measurements of lactate dehydrogenase (LDH) and myeloperoxidase. In MCP-1-/- mice, restoration of perfusion was delayed, and LDH and fiber size, indicators of muscle regeneration, were decreased. Altered inflammation was observed with increased neutrophil accumulation in MCP-1-/- versus WT mice at Days 1 and 3 (P< or =0.003), whereas fewer macrophages were present in MCP-1-/- mice at Day 3. As necrotic tissue was removed in WT mice, macrophages decreased (Day 7). In contrast, macrophage accumulation in MCP-1-/- was increased in association with residual necrotic tissue and impaired muscle regeneration. Consistent with altered inflammation, neutrophil chemotactic factors (keratinocyte-derived chemokine and macrophage inflammatory protein-2) were increased at Day 1 post-FAE. The macrophage chemotactic factor MCP-5 was increased significantly in WT mice at Day 3 compared with MCP-1-/- mice. However, at post-FAE Day 7, MCP-5 was significantly elevated in MCP-1-/- mice versus WT mice. Addition of exogenous MCP-1 did not induce proliferation in murine myoblasts (C2C12 cells) in vitro. MCP-1 is essential for reperfusion and the successful completion of normal skeletal muscle regeneration after ischemic tissue injury. Impaired muscle regeneration in MCP-1-/- mice suggests an important role for macrophages and MCP-1 in tissue reparative processes. PMID:17135576

  18. Adsorptive desulfurization by activated alumina.

    Science.gov (United States)

    Srivastav, Ankur; Srivastava, Vimal Chandra

    2009-10-30

    This study reports usage of commercial grade activated alumina (aluminum oxide) as adsorbent for the removal of sulfur from model oil (dibenthiophene (DBT) dissolved in n-hexane). Bulk density of alumina was found to be 1177.77 kg/m(3). The BET surface area of alumina was found to decrease from 143.6 to 66.4 m(2)/g after the loading of DBT at optimum conditions. The carbon-oxygen functional groups present on the surface of alumina were found to be effective in the adsorption of DBT onto alumina. Optimum adsorbent dose was found to be 20 g/l. The adsorption of DBT on alumina was found to be gradual process, and quasi-equilibrium reached in 24 h. Langmuir isotherm best represented the equilibrium adsorption data. The heat of adsorption and change in entropy for DBT adsorption onto alumina was found to be 19.5 kJ/mol and 139.2 kJ/mol K, respectively. PMID:19523762

  19. Autocrine MCP-1/CCR2 signaling stimulates proliferation and migration of renal carcinoma cells

    Science.gov (United States)

    Küper, Christoph; Beck, Franz-Xaver; Neuhofer, Wolfgang

    2016-01-01

    The chemokine monocyte chemoattractant protein-1 [MCP-1; also known as chemokine (C-C motif) ligand 2] is an important mediator of monocyte recruitment during inflammatory processes. Pathologically high expression levels of MCP-1 by tumor cells have been observed in a variety of cancer types. In the majority of cases, high MCP-1 expression is associated with a poor prognosis, as infiltration of the tumor with inflammatory monocytes promotes tumor progression and metastasis. MCP-1 is also expressed in renal cell carcinoma (RCC). In the present study, the function and the regulation of MCP-1 was investigated in two RCC cell lines, CaKi-1 and 786-O. In both cell lines, expression of MCP-1 was significantly enhanced compared with non-cancerous control cells. As expected, secretion of MCP-1 into the medium facilitated the recruitment of peripheral blood monocytes via the chemokine (C-C motif) receptor type 2 (CCR2). As expression of CCR2 was also detected in 786-O and CaKi-1 cells, the effect of autocrine MCP-1/CCR2 signaling was evaluated in these cells. In proliferation assays, administration of an MCP-1 neutralizing antibody or of a CCR2 antagonist to CaKi-1 and 786-O cells significantly decreased cell growth; supplementation of the growth medium with recombinant human MCP-1 had no additional effect on proliferation. The migration ability of RCC cells was impaired by MCP-1 neutralization or pharmacological CCR2 inhibition, while it was stimulated by the addition of recombinant human MCP-1, compared with untreated control cells. Finally, substantial differences in the regulation of MCP-1 expression were observed between RCC cell lines. In CaKi-1 cells, expression of MCP-1 appears to be largely mediated by the transcription factor nuclear factor of activated T cells 5, while in 786-O cells, deletion of the tumor suppressor gene Von-Hippel-Lindau appeared to be responsible for MCP-1 upregulation, as suggested by previous studies. Taken together, the results of the

  20. Influence of the inner diameters of capillary on the Z-Pinch plasma of the capillary discharge soft X-ray laser

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Shan; Zhao, Yong-peng; Cui, Huai-yu; Li, Lian-bo; Ding, Yu-jie; Zhang, Wen-hong; Li, Wei [National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150080, Heilongjiang (China)

    2015-09-15

    In this paper, the effects of inner diameters on the Z-pinch plasma of capillary discharge soft X-ray laser were investigated with the 3.2 mm and 4.0 mm inner diameter alumina capillaries. The intensities of the laser emitted from the 3.2 mm and 4.0 mm inner diameter alumina capillaries were measured under different initial pressures. To understand the underlying physics of the experimental measurements, the Z-pinch plasma simulations had been conducted with a one-dimensional cylindrical symmetry Lagrangian magneto-hydrodynamics (MHD) code. The parametric studies of Z-pinch plasma, such as the electron temperature, the electron density and the Ne-like Ar ion density, were performed with the MHD code. With the experimental and the simulated results, the discussions had been conducted on the Z-pinch plasma of Ne-like Ar 46.9 nm laser with the 3.2 mm and 4.0 mm inner diameter alumina capillaries. The analysis had been made on the difference of the gain coefficients under the optimum pressures with both capillaries. Then, the effects of inner diameters on the optimum pressure and the pressure domain were analyzed. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. MCP-1 expressed by osteoclasts stimulates osteoclastogenesis in an autocrine/paracrine manner

    International Nuclear Information System (INIS)

    Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that plays a critical role in the recruitment and activation of leukocytes. Here, we describe that multinuclear osteoclast formation was significantly inhibited in cells derived from MCP-1-deficient mice. MCP-1 has been implicated in the regulation of osteoclast cell-cell fusion; however defects of multinuclear osteoclast formation in the cells from mice deficient in DC-STAMP, a seven transmembrane receptor essential for osteoclast cell-cell fusion, was not rescued by recombinant MCP-1. The lack of MCP-1 in osteoclasts resulted in a down-regulation of DC-STAMP, NFATc1, and cathepsin K, all of which were highly expressed in normal osteoclasts, suggesting that osteoclast differentiation was inhibited in MCP-1-deficient cells. MCP-1 alone did not induce osteoclastogenesis, however, the inhibition of osteoclastogenesis in MCP-1-deficient cells was restored by addition of recombinant MCP-1, indicating that osteoclastogenesis was regulated in an autocrine/paracrine manner by MCP-1 under the stimulation of RANKL in osteoclasts.

  2. Alumina-Reinforced Zirconia Composites

    Science.gov (United States)

    Choi, Sung R.; Bansal, Narottam P.

    2003-01-01

    Alumina-reinforced zirconia composites, used as electrolyte materials for solid oxide fuel cells, were fabricated by hot pressing 10 mol percent yttria-stabilized zirconia (10-YSZ) reinforced with two different forms of alumina particulates and platelets each containing 0 to 30 mol percent alumina. Major mechanical and physical properties of both particulate and platelet composites including flexure strength, fracture toughness, slow crack growth, elastic modulus, density, Vickers microhardness, thermal conductivity, and microstructures were determined as a function of alumina content either at 25 C or at both 25 and 1000 C. Flexure strength and fracture toughness at 1000 C were maximized with 30 particulate and 30 mol percent platelet composites, respectively, while resistance to slow crack growth at 1000 C in air was greater for 30 mol percent platelet composite than for 30 mol percent particulate composites.

  3. Alumina supported iridium catalysts - preparation

    International Nuclear Information System (INIS)

    This report describes the method employed in the preparation of alumina supported iridium catalysts, with metal contents between 30 and 40%, that will be used for hydrazine monopropellant decomposition. (author)

  4. Influence of Sulphur Impurities on the Interfacial Tension between Aluminium and Cryolite Alumina Melts

    Science.gov (United States)

    Korenko, Michal

    2007-06-01

    The interfacial tension (IFT) between aluminium and cryolite melts containing different salt additions (AlF3, NaF,Na2SO4) has been measured during electrolysis by the capillary depression method. The technique is based on the measurement of the capillary depression occurring when a capillary, which is moved vertically down through the molten salt layer, passes through the metal/salt interface. The depression is measured by simultaneous video recording of the immersion height of the alumina capillary. The interfacial tension is strongly dependent on the n(NaF)/n(AlF3) ratio. The addition of Na2SO4 decreases the IFT of the aluminium/electrolyte interface. We also found the different influence of the conditions of electrolysis on the IFT in systems with and without Na2SO4. In systems without Na2SO4 the IFT decreases with increasing current density, and in systems with Na2SO4 it increases.

  5. Cycle analysis of an alkali metal thermo-electric converter for small capillary type

    International Nuclear Information System (INIS)

    This paper describes the design of a small size Alkali Metal Thermal to Electric Converter (AMTEC) which employs a capillary structure for recirculating sodium working fluid. The cycle is based on the simple and small capillary type β-alumina and wick tube element. The proposed cell consists of the 37 conversion elements with capillary tube of 50μm in diameter and the sealed cylindrical vessel of 22mm in outer diameter. Results on the cycle analysis of sodium flow and heat transfer in the cell showed that the expected power output was 4.65 W and the conversion efficiency was 19% for the source temperature of 900 K

  6. Relationships between serum MCP-1 and subclinical kidney disease: African American-Diabetes Heart Study

    OpenAIRE

    Murea Mariana; Register Thomas C; Divers Jasmin; Bowden Donald W; Carr J Jeffrey; Hightower Caresse R; Xu Jianzhao; Smith S Carrie; Hruska Keith A; Langefeld Carl D; Freedman Barry I

    2012-01-01

    Abstract Background Monocyte chemoattractant protein-1 (MCP-1) plays important roles in kidney disease susceptibility and atherogenesis in experimental models. Relationships between serum MCP-1 concentration and early nephropathy and subclinical cardiovascular disease (CVD) were assessed in African Americans (AAs) with type 2 diabetes (T2D). Methods Serum MCP-1 concentration, urine albumin:creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and atherosclerotic calcified plaqu...

  7. Intramedullary capillary haemangioma.

    LENUS (Irish Health Repository)

    Kelleher, T

    2012-02-03

    Intramedullary capillary haemangioma is extremely rare and only four cases have been previously reported. We describe a further case, outlining the clinical, radiological, surgical and pathological features.

  8. Ultraviolet variability of the mCP star 56 Arietis

    CERN Document Server

    Sokolov, N A

    2010-01-01

    The spectrophotometric variability of the mCP star 56 Ari in the far-UV spectral region from 1150 \\AA\\ to 1980 \\AA\\ is investigated. This study is based on the archival {\\it IUE} data obtained at different phases of the rotational cycle. The brightness of 56 Ari is not constant in the investigated wavelengths over the whole rotational period. The monochromatic light curves continuously change their shape with wavelength. The comparison of energy distributions at three phases show that the first minimum of light curves at phase 0.25 is replaced by the maximum for $\\lambda>$1608\\AA, but the second minimum of light curves at phase 0.65 absent in the spectral region between $\\lambda$1938\\AA\\ and $\\lambda$1980\\AA. The variable broad features in the far-UV connected with a non-uniform distribution of silicon over the surface of 56 Ari influence substantially the light variations in the UV.

  9. Gelcasting polycrystalline alumina

    Energy Technology Data Exchange (ETDEWEB)

    Janney, M.A. [Oak Ridge National Lab., TN (United States)

    1997-04-01

    This work is being done as part of a CRADA with Osram-Sylvania, Inc. (OSI) OSI is a major U.S. manufacturer of high-intensity lighting. Among its products is the Lumalux{reg_sign} line of high-pressure sodium vapor arc lamps, which are used for industrial, highway, and street lighting. The key to the performance of these lamps is the polycrystalline alumina (PCA) tube that is used to contain the plasma that is formed in the electric arc. That plasma consists of ionized sodium, mercury, and xenon vapors. The key attributes of the PCA tubes are their transparency (95% total transmittance in the visible region), their refractoriness (inner wall temperature can reach 1400{degrees}C), and their chemical resistance (sodium and mercury vapor are extremely corrosive). The current efficiency of the lamps is very high, on the order of several hundred lumens / watt. (Compare - incandescent lamps -13 lumens/watt fluorescent lamps -30 lumens/watt.) Osram-Sylvania would like to explore using gelcasting to form PCA tubes for Lumalux{reg_sign} lamps, and eventually for metal halide lamps (known as quartz-halogen lamps). Osram-Sylvania, Inc. currently manufactures PCA tubes by isostatic pressing. This process works well for the shapes that they presently use. However, there are several types of tubes that are either difficult or impossible to make by isostatic pressing. It is the desire to make these new shapes and sizes of tubes that has prompted Osram-Sylvania`s interest in gelcasting. The purpose of the CRADA is to determine the feasibility of making PCA items having sufficient optical quality that they are useful in lighting applications using gelcasting.

  10. The R&D of the 20 in. MCP-PMTs for JUNO

    Science.gov (United States)

    Chang, Yaping; Huang, Guorui; Heng, Yuekun; Li, Dong; Liu, Huilin; Liu, Shulin; Li, Weihua; Ning, Zhe; Qi, Ming; Qian, Sen; Sun, Jianning; Si, Shuguang; Tian, Jinshou; Wang, Xingchao; Wang, Xing; Wang, Yifang; Wei, Yonglin; Wang, Wenwen; Xia, Jingkai; Xin, Liwei; Zhao, Tianchi

    2016-07-01

    A new concept of large area photomultiplier based on MCPs was conceived for JUNO by the scientists in IHEP, and with the collaborative work of the MCP-PMT collaboration in China, 8 in. and 20 in. prototypes were produced. Test results show that this type of MCP-PMT can have good SPE performance as the traditional dynode type PMTs.

  11. Ethylene-inhibiting compound 1-MCP delays leaf senescence in cotton plants under abiotic stress conditions

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuan; J T Cothren; CHEN De-hua; Amir M H Ibrahim; Leonardo Lombardini

    2015-01-01

    Cotton (Gossypium hirsutum L.) plants produce more ethylene when subjected to abiotic stresses, such as high temperatures and drought, which result in premature leaf senescence, reduced photosynthetic efifciency, and thus decreased yield. This study was conducted to test the hypothesis that the ethylene-inhibiting compound 1-methylcyclopropene (1-MCP) treatment of cotton plants can delay leaf senescence under high temperature, drought, and the aging process in control ed environ-mental conditions. Potted cotton plants were exposed to 1-MCP treatment at the early square stage of development. The protective effect of 1-MCP against membrane damage was found on older compared to younger leaves, indicating 1-MCP could lower the stress level caused by aging. Application of 1-MCP resulted in reduction of lipid peroxidation, membrane leakage, soluble sugar content, and increased chlorophyl content, in contrast to the untreated plants under heat stress, suggesting that 1-MCP treatment of cotton plants may also have the potential to reduce the effect of heat stress in terms of delayed senescence. Application of 1-MCP caused reductions of lipid peroxidation, membrane leakage, and soluble sugar content, together with increases in water use efifciency (WUE), water potential, chlorophyl content, and lfuorescence quantum efifciency, compared to the untreated plants under drought, suggesting that 1-MCP treatment of cotton plants may also have the ability to reduce the level of stress under drought conditions. In conclusion, 1-MCP treatment of cotton should have the potential to delay senescence under heat and drought stress, and the aging process. Additional y, 1-MCP is more effective under stress than under non-stress conditions.

  12. Dynamic Tensile Response of Structured Alumina-Al Composites

    Science.gov (United States)

    Atisivan, Raj; Bandyopadhyay, Amit; Gupta, Yogendra

    2001-06-01

    Plate impact experiments were carried out to examine the high strain-rate tensile response of alumina-aluminum composites with tailored microstructures. A novel processing technique was used to fabricate interpenetrating phase alumina-aluminum composites with controlled and reproducible microstructures. Fused deposition modeling (FDM), a commercially available rapid prototyping technique, was used to produce the controlled porosity mullite ceramic preforms. Alumina-Al composites were then processed via reactive metal infiltration of porous mullite ceramics. With this approach, both the micro as well as the macro structures can be designed via computer aided design (CAD) to tailor the properties of the composites. Two sets of dynamic tensile experiments were performed. In the first, the metal content was varied between 23 and 39 wt. percent. In the second, the microstructure was varied while holding the metal content nearly constant. Samples with higher metal content, as expected, displayed better spall resistance. For a given metal content, samples with finer metal diameter showed better spall resistance. Relationship of the microstructural parameters on the dynamic tensile response of the structured composites will be discussed. Work supported by DOE.

  13. Capillary saturation and desaturation.

    Science.gov (United States)

    Hilfer, R; Armstrong, R T; Berg, S; Georgiadis, A; Ott, H

    2015-12-01

    Capillary desaturation experiments produce disconnected (trapped) ganglia of mesoscopic sizes intermediate between pore size and system size. Experimental evidence for interactions between these mesoscale clusters during desaturation is analyzed and discussed within the established microscopic and macroscopic laws of Newton, Young-Laplace, and Darcy. A theoretical expression for capillary number correlations is introduced that seems to have remained unnoticed. It expresses capillary desaturation curves in terms of stationary capillary pressures and relative permeabilities. The theoretical expression shows that the plateau saturation in capillary desaturation curves may in general differ from the residual nonwetting saturation defined through the saturation limit of the main hysteresis loop. Hysteresis effects as well as the difference between wetting and nonwetting fluids are introduced into the analysis of capillary desaturation experiments. The article examines experiments with different desaturation protocols and discusses the existence of a mesoscopic length scale intermediate between pore scale and sample scale. The theoretical expression is derived entirely within the existing traditional theory of two-phase flow in porous media and compared to a recent experiment. PMID:26764820

  14. Capillary saturation and desaturation

    Science.gov (United States)

    Hilfer, R.; Armstrong, R. T.; Berg, S.; Georgiadis, A.; Ott, H.

    2015-12-01

    Capillary desaturation experiments produce disconnected (trapped) ganglia of mesoscopic sizes intermediate between pore size and system size. Experimental evidence for interactions between these mesoscale clusters during desaturation is analyzed and discussed within the established microscopic and macroscopic laws of Newton, Young-Laplace, and Darcy. A theoretical expression for capillary number correlations is introduced that seems to have remained unnoticed. It expresses capillary desaturation curves in terms of stationary capillary pressures and relative permeabilities. The theoretical expression shows that the plateau saturation in capillary desaturation curves may in general differ from the residual nonwetting saturation defined through the saturation limit of the main hysteresis loop. Hysteresis effects as well as the difference between wetting and nonwetting fluids are introduced into the analysis of capillary desaturation experiments. The article examines experiments with different desaturation protocols and discusses the existence of a mesoscopic length scale intermediate between pore scale and sample scale. The theoretical expression is derived entirely within the existing traditional theory of two-phase flow in porous media and compared to a recent experiment.

  15. Development and production of the MCP-PMT for the Belle II TOP counter

    International Nuclear Information System (INIS)

    A square shape multi-anode micro-channel-plate photomultiplier tube (MCP-PMT) was developed for the Belle II TOP counter. It has a 23×23 mm2 multi-alkali photocathode with a peak quantum efficiency (QE) of 28% around a wavelength of 360 nm. It has a 2×106 gain and is capable of detecting a single photon with a transit time spread (TTS) of 40 ps or less. The QE, gain and TTS were measured for each MCP-PMT to check the quality in the mass production of 550 MCP-PMTs. The lifetime of the MCP-PMT was extended to 10 C/cm2 by adapting the atomic layer deposition technique for the MCP coating. Other properties of the MCP-PMT are also discussed: the angle and polarization dependence of the QE, and the effects of charge sharing and cross-talk. A prototype TOP counter was tested with a 2 GeV/c positron beam. The distribution of the time of propagation was consistent with the calculated expectation which included those properties of the MCP-PMT

  16. Effect Of 1-MCP Treatment On Storage Potential Of Tomato Fruit

    Directory of Open Access Journals (Sweden)

    Wrzodak Anna

    2015-12-01

    Full Text Available Tomato fruit cv. ’Faustine’ F1 were harvested at mature green and full-red stages and treated with 1 or 2 µl·l−1 of 1-methylcyclopropene (1-MCP at 20 °C and 85-90% RH, for 21 hours to investigate the ability to delay ripening. Treated and control fruit were stored at 12.5 and 20 °C and 85-90% RH. Ethylene production, rate of respiration, weight loss, market value and storage life were determined after 4-week storage. Exposure of tomato fruit to 1-MCP reduced ethylene production and respiration rate of the fruit harvested at mature-green and full-red stages of maturity. Storage life and market value of tomato fruit depended on the treatment with 1-MCP, stage of maturity and storage temperature. Untreated fruits were characterized by the shortest storage life in comparison with the fruit treated with 1-MCP. The lowest market value was observed for tomato fruit harvested as a mature green, untreated with 1-MCP and stored at 20 °C. Treatment of tomato fruit with 1-MCP resulted in the reduction of natural weight loss during storage. These results suggest that 1-MCP treatment can be used in a commercial storage and trading system for tomatoes due to its ability to delay fruit ripening.

  17. NFAT5 Contributes to Osmolality-Induced MCP-1 Expression in Mesothelial Cells

    Directory of Open Access Journals (Sweden)

    Christoph Küper

    2012-01-01

    Full Text Available Increased expression of the C-C chemokine monocyte chemoattractant protein-1 (MCP-1 in mesothelial cells in response to high glucose concentrations and/or high osmolality plays a crucial role in the development of peritoneal fibrosis during continuous ambulatory peritoneal dialysis (CAPD. Recent studies suggest that in kidney cells osmolality-induced MCP-1 upregulation is mediated by the osmosensitive transcription factor, nuclear factor of activated T cells 5 (NFAT5. The present study addressed the question of whether activation of NFAT5 by hyperosmolality, as present in PD fluids, contributes to MCP-1 expression in the mesothelial cell line Met5A. Hyperosmolality, induced by addition of glucose, NaCl, or mannitol to the growth medium, increased NFAT5 activity and stimulated MCP-1 expression in Met5A cells. siRNA-mediated knockdown of NFAT5 attenuated osmolality-induced MCP-1 upregulation substantially. Hyperosmolality also induced activation of nuclear factor-κB (NF-κB. Accordingly, pharmacological inhibition of NF-κB significantly decreased osmolality-induced MCP-1 expression. Taken together, these results indicate that high osmolalities activate the transcription factor NFAT5 in mesothelial cells. NFAT5 in turn upregulates MCP-1, likely in combination with NF-κB, and thus may participate in the development of peritoneal fibrosis during CAPD.

  18. Membrane cofactor protein (MCP or CD46) is a cellular pilus receptor for pathogenic Neisseria.

    Science.gov (United States)

    Källström, H; Liszewski, M K; Atkinson, J P; Jonsson, A B

    1997-08-01

    Pili of Neisseria gonorrhoeae and Neisseria meningitidis mediate binding of the bacteria to human cell-surface receptors. We found that purified pili bound to a 55- to 60-kDa doublet band on SDS-PAGE of separated human epithelial cell extracts. This is a migration pattern typical of membrane cofactor protein (MCP or CD46). MCP is a widely distributed human complement regulatory protein. Attachment of the bacteria to epithelial cells was blocked by polyclonal and monoclonal antibodies directed against MCP, suggesting that this complement regulator is a receptor for piliated Neisseria. We proved this hypothesis by demonstrating that piliated, but not non-piliated, gonococci bound to CHO cells transfected with human MCP-cDNA. We also demonstrated a direct interaction between purified recombinant MCP and piliated Neisseria. Finally, recombinant MCP protein produced in E. coli inhibited attachment of the bacteria to target cells. Taken together, our data show that MCP is a human cell-surface receptor for piliated pathogenic Neisseria. PMID:9379894

  19. MCP-Optics for X-ray Timing

    International Nuclear Information System (INIS)

    Very lightweight X-ray optics are being developed by ESA and its industrial partners, for a number of X-ray astronomy and planetary missions. These developments could significantly improve the performance of future X-ray timing instrumentation. Based on Micro-Channel Plates (MCPs), the novel optics effectively reduce the mirror thickness by almost two orders of magnitude, and therefore also the mass of the telescope optics. Very large collecting areas become feasible for space implementation, especially as required for X-ray timing observations. Furthermore this technology leads to much reduced detector sizes due to the use of imaging X-ray optics. This dramatically improves the detected signal-to-noise ratios, as well as introducing photon collection areas sufficiently large as to study temporal phenomena on the millisecond time scale. This is particularly important to improve the studies of compact X-ray sources, both for improving the signal:noise ratios in temporal bins so that spectral or fluctuation analyses are improved, and for extending the range of measurements to fainter classes of objects.We present a brief overview of the MCP optics technology, and some basic design rules relevant to such systems. The performance of such optics and some possible mission implementations will be discussed

  20. MECHANICAL BEHAVIOUR OF ALUMINA-ZIRCONIA COMPOSITE BY SLURRY METHOD

    OpenAIRE

    JYOTI PRAKASH; DEVENDRA KUMAR; KALYANI MOHANTA

    2011-01-01

    Alumina has got some excellent properties like chemical inertness, thermal and mechanical strength against hazardous environment. Alumina is a good ceramic material which is being used for structuralapplications. To enhance the toughness and strength of the body some Zirconia is also used with it. The use of Zirconia in alumina is known as toughening of alumina. One difficulty arises, when alumina and alumina toughened composite are sintered , because the low sinterability of Alumina-Zirconia...

  1. Evaluating the potential of IP-10 and MCP-2 as biomarkers for the diagnosis of TB

    DEFF Research Database (Denmark)

    Ruhwald, Morten; Bodmer, T; Maier, C; Jepsen, M; Andersen, M B; Eugen-Olsen, Jesper; Ravn, Pernille; NN, NN

    2008-01-01

    The aim of the study was to evaluate the potential of diagnostic tests based on IP-10 and MCP-2, and compare the performance with the Quantiferon-Gold In-Tube (QFT-IT) test.IP-10 and MCP-2 were determined in supernatants from whole blood stimulated with M.tuberculosis-specific antigens. Samples...... were obtained from 80 patients with culture and/or PCR proven TB, and 124 unexposed healthy controls; 86 high school students and 38 high school staff. IP-10 and MCP-2 test cut-offs were established based on ROC curve analysis.TB patients produced significantly higher levels of IP-10 (median 2158 pg...

  2. Processing and Performance of Alumina Fiber Reinforced Alumina Composites

    Institute of Scientific and Technical Information of China (English)

    P.Y.Lee; T.Uchijima; T.Yano

    2003-01-01

    Processing of alumina fiber-reinforced alumina matrix composites by hot-pressing was described. The mechanical properties of the composites fabricated by different sintering conditions including temperature and pressure have been investigated. The results indicated that the higher sintering temperature and pressure corresponded to the higher bulk density and higher maximum strength of the composite, whereas the pseudo-ductility of the composite was lower. The preliminary results of the composite with monazite-coated fibers showed that maximum strength could be improved up to 35% compared with the noncoated fiber composite in the same sintering condition. Moreover, the fracture behavior of the composite changed from completely brittle fracture to non-brittle fracture under the suitable sintering conditions. SEM observation of the fracture surface indicated that the coating worked as a protective barrier and avoided sintering of the fibers together even at high temperature and pressure during densification process.

  3. Sintering behaviour of spinel–alumina composites

    Indian Academy of Sciences (India)

    Soumen Pal; A K Bandyopadhyay; P G Pal; S Mukherjee; B N Samaddar

    2009-04-01

    Study of alumina–magnesia binary phase diagram reveals that around 40–50 wt% alumina dissolves in spinel (MgAl2O4) at 1600°C. Solid solubility of alumina in spinel decreases rapidly with decreasing temperature, which causes exsolution of alumina from spinel phase. Previous work of one of the authors revealed that the exsolution of alumina makes some interlocking structures in between alumina and spinel phases. In the present investigation, refractory grade calcined alumina and spinel powder were used to make different batch compositions. Green pellets, formed at a pressure of 1550 kg cm-2 were fired at different temperatures of 1500°, 1550° and 1600°C for 2 h soaking time. Bulk density, percent apparent porosity, firing shrinkage etc were measured at each temperature. Sintering results were analysed to understand the mechanism of spinel–alumina interactions. SEM study of present samples does not reveal the distinct precipitation of needle shaped -alumina from spinel, but has some effect on densification process of spinel–alumina composites. Microstructural differences between present and previous work suggest an ample scope of further work in spinel–alumina composites.

  4. Extended lifetime MCP-PMTs: Characterisation and lifetime measurements of ALD coated microchannel plates, in a sealed photomultiplier tube

    International Nuclear Information System (INIS)

    Atomic layer deposition (ALD) coating of microchannel plates (MCP) has been shown to offer significant performance advantages in MCP-PMTs (MCP Photomultiplier Tube). ALD is a chemical vapour process used to deposit atomic mono-layers on a substrate. A process has been developed to deposit a surface with improved secondary emission yield (SEY) on to an MCP substrate. The principal advantage of a higher SEY is the ability to achieve significantly higher gain at the same operating voltage across a single MCP. Further to this, it is suspected the atomic mono-layers deposited by ALD coating prevent desorption of gaseous contaminants in the MCP glass. The ions produced during desorption are widely believed to be a direct cause of photocathode ageing in MCP-PMTs, leading to the hope that ALD coating can improve the MCP-PMT lifetime. To fully characterise the performance of ALD coated MCPs, two MCP-PMTs were manufactured, one ALD coated and the other uncoated to be used as a reference. Each detector's gain, DQE, pulse shape and timing jitter were measured followed by a life test of the tubes. The ALD coated tube was found to have a higher gain at the same operating voltage, whilst being equivalent to a standard MCP in other performance characteristics. ALD coating gave a dramatically improved life time, after 5.16 C cm−2 total charge extracted, there was no measurable effect on the photocathode QE, although the MCP gain dropped by approximately 35%

  5. Synthesis of zirconia toughened alumina

    International Nuclear Information System (INIS)

    This paper deals with the synthesis of zirconia toughened alumina (ZTA) and evaluation of its mechanical properties. ZTA ceramics were prepared by partial chemical route. High purity alumina (particle size 0.48 μm) was coated with yttria stabilised zirconia through solution techniques. Small amounts of dopants such as MgO, MnO and TiO2 were added to ZTA as densification aids. These powders were calcined at 650 deg C for 1 hour, followed by wet ball milling, compaction, sintering at 1600 deg C for 2.5 hour. Sintered density values upto 90% of theoretical density of ZTA were achieved. Hardness values upto 1800 VPN and modulus of rupture values upto 180 MPa were obtained. (author)

  6. Relationships between serum MCP-1 and subclinical kidney disease: African American-Diabetes Heart Study

    Directory of Open Access Journals (Sweden)

    Murea Mariana

    2012-11-01

    Full Text Available Abstract Background Monocyte chemoattractant protein-1 (MCP-1 plays important roles in kidney disease susceptibility and atherogenesis in experimental models. Relationships between serum MCP-1 concentration and early nephropathy and subclinical cardiovascular disease (CVD were assessed in African Americans (AAs with type 2 diabetes (T2D. Methods Serum MCP-1 concentration, urine albumin:creatinine ratio (ACR, estimated glomerular filtration rate (eGFR, and atherosclerotic calcified plaque (CP in the coronary and carotid arteries and infrarenal aorta were measured in 479 unrelated AAs with T2D. Generalized linear models were fitted to test for associations between MCP-1 and urine ACR, eGFR, and CP. Results Participants were 57% female, with mean ± SD (median age 55.6±9.5 (55.0 years, diabetes duration 10.3±8.2 (8.0 years, urine ACR 149.7±566.7 (14.0 mg/g, CKD-EPI eGFR 92.4±23.3 (92.0 ml/min/1.73m2, MCP-1 262.9±239.1 (224.4 pg/ml, coronary artery CP 280.1±633.8 (13.5, carotid artery CP 47.1±132.9 (0, and aorta CP 1616.0±2864.0 (319.0. Adjusting for age, sex, smoking, HbA1c, BMI, and LDL, serum MCP-1 was positively associated with albuminuria (parameter estimate 0.0021, P=0.04 and negatively associated with eGFR (parameter estimate −0.0003, P=0.001. MCP-1 remained associated with eGFR after adjustment for urine ACR. MCP-1 levels did not correlate with the extent of CP in any vascular bed, HbA1c or diabetes duration, but were positively associated with BMI. No interaction between BMI and MCP-1 was detected on nephropathy outcomes. Conclusions Serum MCP-1 levels are associated with eGFR and albuminuria in AAs with T2D. MCP-1 was not associated with subclinical CVD in this population. Inflammation appears to play important roles in development and/or progression of kidney disease in AAs.

  7. Bauxite Mining and Alumina Refining

    OpenAIRE

    Donoghue, A. Michael; Frisch, Neale; Olney, David

    2014-01-01

    Objective: To describe bauxite mining and alumina refining processes and to outline the relevant physical, chemical, biological, ergonomic, and psychosocial health risks. Methods: Review article. Results: The most important risks relate to noise, ergonomics, trauma, and caustic soda splashes of the skin/eyes. Other risks of note relate to fatigue, heat, and solar ultraviolet and for some operations tropical diseases, venomous/dangerous animals, and remote locations. Exposures to bauxite dust,...

  8. Regulation of MCP-1 gene transcription by Smads and HIV-1 Tat in human glial cells

    International Nuclear Information System (INIS)

    Expression of several cytokines involved in signal transduction such as TGFβ-1 and the inflammatory chemokines including MCP-1 is elevated during the course of AIDS progression. The enhancement of these cellular proteins in astrocytic cells is mediated, at least in part, by HIV-1 Tat protein. Here, we investigate the possible regulation of MCP-1 transcription by Tat and the Smad family of transcription factors whose activities are induced by the TGFβ-1 pathway. Results from transfection studies revealed that Smad-3 stimulates basal and Tat-mediated transcription of MCP-1 in human astrocytic cells. Smad-4, on the other hand, had no effect on the basal activity of the MCP-1 promoter, but showed the ability to decrease both Smad-3 and Tat-induced transcription of the MCP promoter. Results from protein-binding studies revealed the ability of both Smad-3 and Smad-4 to associate with the region of Tat spanning residues 1-40. Examination of the transcriptional activity of the various domains of Smad including MH1, at the N-terminus, and MH2, at the C-terminus of the protein indicated that neither MH1 or MH2 alone positively cooperate with Tat in modulating MCP-1 transcription. However, ectopic expression of MH1 and, more notably, MH2 severely suppressed transcriptional activation of MCP-1 by Tat in astrocytic cells. Binding studies revealed that similar to the full-length Smad protein, both MH1 and MH2 associate with Tat protein and that the residues between 1 and 40 of Tat are important for their interaction. These observations reveal a novel mechanism for Tat-mediated transcriptional activation via TGFβ signaling pathway and provide evidence for regulation of MCP-1 gene transcription by this signaling pathway in human astrocytic cells

  9. Elevated bronchoalveolar concentrations of MCP-1 in patients with pulmonary alveolar proteinosis.

    Science.gov (United States)

    Iyonaga, K; Suga, M; Yamamoto, T; Ichiyasu, H; Miyakawa, H; Ando, M

    1999-08-01

    Pulmonary alveolar proteinosis (PAP) is a rare disease of unknown aetiology characterized by accumulations of lipoproteinaceous material within the alveoli. The alveolar macrophages become increasingly foamy, and are thought to have a role in the pathogenesis of PAP. However, the mechanisms of macrophage recruitment are unclear. In the bronchoalveolar lavage fluid (BALF) of four patients with PAP and 20 normal control subjects, the following were examined: the monocyte chemotactic activity due to the chemokine monocyte chemoattractant protein (MCP)-1 with the use of a chemotactic chamber assay, the levels of MCP-1 by enzyme-linked immunosorbent assay, and the MCP-1 expression on lavage cells by immunocytochemistry and in situ hybridization. The monocyte chemotactic activity in the BALF of the PAP patients was markedly elevated, and the activity was completely absorbed by treatment with anti-MCP-1. The MCP-1 levels in the BALF were surprisingly high in the PAP group (25,100+/-472 pg x mL(-1)), whereas low levels of MCP-1 were detected in the normal control subjects (mean: never smokers 4.8; smokers 10.4 pg x mL(-1)). MCP-1 protein and messenger ribonucleic acid were expressed by macrophages from the PAP patients, and the expression was reduced according to foaming of the cells; there were monocyte-like macrophages with strong expression, small foamy cells with moderate expression, large foamy cells with a faint expression of MCP-1, and ghost cells with no expression. However, the increase of macrophage number in the PAP BALF was relatively small. These data suggest that monocyte chemoattractant protein(-1) expression by alveolar macrophages represents an amplification mechanism for the recruitment of additional macrophages to the alveoli in pulmonary alveolar proteinosis. It is possible that an ingestion of an excess of alveolar materials in pulmonary alveolar proteinosis may impair the macrophage function and the survival, resulting in the lack of a prominent

  10. Endogenous PGE(2) induces MCP-1 expression via EP4/p38 MAPK signaling in melanoma.

    Science.gov (United States)

    Tang, Mingrui; Wang, Yuxin; Han, Sihuan; Guo, Shu; Xu, Nan; Guo, Jiayan

    2013-02-01

    It has been demonstrated that cyclooxygenase-2 (COX-2) is expressed in melanoma tissues and prostaglandin E(2) (PGE(2)) is produced by melanoma cells in vitro. However, the roles of COX-2/PGE(2) in melanoma are largely unknown. In the present study, we set out to analyze the correlation of endogenous PGE(2) with the expression of macrophage chemoattractant protein-1 (MCP-1) and to identify the signaling pathway involved. It was found that MCP-1 mRNA was heterogeneously expressed in 18 melanoma tissue specimens, and the levels of MCP-1 mRNA were positively correlated with those of COX-2 mRNA. Inhibition of endogenous PGE(2) production by a COX-2 inhibitor, COX-2 siRNA or an NFκB inhibitor suppressed MCP-1 expression, whereas treatment with TNF-α (to stimulate endogenous PGE(2) production) or exogenous PGE(2) enhanced MCP-1 expression in melanoma cells. Both the EP4 antagonist and the p38 MAPK inhibitor reduced MCP-1 production in melanoma cells, and abrogated the increased MCP-1 secretion induced by TNF-α or exogenous PGE(2). Conditioned medium from melanoma cells promoted macrophage migration, which was blocked by inhibitors of the PGE(2)/EP4/p38 MAPK signaling pathway. These results indicate that endogenous PGE(2) induces MCP-1 expression via EP4/p38 MAPK signaling in an autocrinal manner in melanoma, and melanoma cell-derived PGE(2) may be involved in macrophage recruitment in the melanoma microenvironment. PMID:23420676

  11. Efficiency optimization of microchannel plate (MCP) neutron imaging detectors. 1. Square channels with B-10 doping

    OpenAIRE

    Tremsin, A.S.; Feller, W. B.; Downing, R. G.

    2005-01-01

    Microchannel plate (MCP) event-counting imaging detectors with very high spatial resolution (~10 um) and timing accuracy (~100 ps) are widely employed for the detection and imaging applications of electrons and ions, as well as UV and X-ray photons. Recently, it was demonstrated that the many advantages of MCPs are also applicable to neutron detection with high two-dimensional spatial resolution. Boron, enriched in the isotope B-10, was added to the MCP glass structure to enhance the neutron ...

  12. Efficiency optimization of microchannel plate (MCP) neutron imaging detectors: I. Square channels with 10B doping.

    OpenAIRE

    Tremsin, Anton S.

    2005-01-01

    Microchannel plate (MCP) event-counting imaging detectors with very high spatial resolution (~10 µm) and timing accuracy (~100 ps) are widely employed for the detection and imaging applications of electrons and ions, as well as UV and X-ray photons. Recently it was demonstrated that the many advantages of MCPs are also applicable to neutron detection with high 2-dimensional spatial resolution. Boron, enriched in the isotope 10B, was added to the MCP glass structure to enhance the neutron inte...

  13. How Capillary Rafts Sink

    CERN Document Server

    Protiere, S; Aristoff, J; Stone, H

    2010-01-01

    We present a fluid dynamics video showing how capillary rafts sink. Small objects trapped at an interface are very common in Nature (insects walking on water, ant rafts, bubbles or pollen at the water-air interface, membranes...) and are found in many multiphase industrial processes. Thanks to Archimedes principle we can easily predict whether an object sinks or floats. But what happens when several small particles are placed at an interface between two fluids. In this case surface tension also plays an important role. These particles self-assemble by capillarity and thus form what we call a "capillary raft". We show how such capillary rafts sink for varying sizes of particles and define how this parameter affects the sinking process.

  14. Performance of the MCP-PMT for the Belle II TOP counter in a magnetic field

    International Nuclear Information System (INIS)

    The time of propagation (TOP) counter is a novel particle identification device for the Belle II experiment, utilizing the ring imaging Cherenkov technique. It is composed of a 2.7 m long quartz bar and 32 micro channel plate photomultiplier tubes (MCP-PMTs) attached on the end of the bar. The MCP-PMT has a typical quantum efficiency of 28%, a photoelectron collection efficiency of about 55%, and a transit time spread (TTS) less than 50 ps for single photon detection. Since the TOP counters are installed in the 1.5 T magnetic field of the Belle II detector, the MCP-PMTs are required to keep those characteristics with gain of more than 5×105 in the magnetic field. Therefore, we investigated gain, TTS, and single photon detection efficiency of the MCP-PMTs in the magnetic field and found that they satisfy the requirements. We are starting complete inspections for more than 500 MCP-PMTs, and have inspected up to 87 MCP-PMTs

  15. Anti-inflammatory effect of resveratrol on TNF-α-induced MCP-1 expression in adipocytes

    International Nuclear Information System (INIS)

    Chronic low-grade inflammation characterized by adipose tissue macrophage accumulation and abnormal cytokine production is a key feature of obesity and type 2 diabetes. Adipose-tissue-derived monocyte chemoattractant protein (MCP)-1, induced by cytokines, has been shown to play an essential role in the early events during macrophage infiltration into adipose tissue. In this study we investigated the effects of resveratrol upon both tumor necrosis factor (TNF)-α-induced MCP-1 gene expression and its underlying signaling pathways in 3T3-L1 adipoctyes. Resveratrol was found to inhibit TNF-α-induced MCP-1 secretion and gene transcription, as well as promoter activity, which based on down-regulation of TNF-α-induced MCP-1 transcription. Nuclear factor (NF)-κB was determined to play a major role in the TNF-α-induced MCP-1 expression. Further analysis showed that resveratrol inhibited DNA binding activity of the NF-κB complex and subsequently suppressed NF-κB transcriptional activity in TNF-α-stimulated cells. Finally, the inhibition of MCP-1 may represent a novel mechanism of resveratrol in preventing obesity-related pathologies

  16. Synthesis of high porosity, monolithic alumina aerogels

    Energy Technology Data Exchange (ETDEWEB)

    Poco, J F; Satcher, J H; Hrubesh, L W

    2000-09-20

    Many non-silica aerogels are notably weak and fragile in monolithic form. Particularly, few monolithic aerogels with densities less than 50kg/m3 have any significant strength. It is especially difficult to prepare uncracked monoliths of pure alumina aerogels that are robust and moisture stable. In this paper, we discuss the synthesis of strong, stable, monolithic, high porosity (>98% porous) alumina aerogels, using a two-step sol-gel process. The alumina aerogels have a polycrystalline morphology that results in enhanced physical properties. Most of the measured physical properties of the alumina aerogels are superior to those for silica aerogels for equivalent densities.

  17. Monocyte chemoattractant protein-1 (MCP-1) inhibits the intestinal-like differentiation of monocytes.

    Science.gov (United States)

    Spoettl, T; Hausmann, M; Herlyn, M; Gunckel, M; Dirmeier, A; Falk, W; Herfarth, H; Schoelmerich, J; Rogler, G

    2006-07-01

    Monocytes (MO) migrating into normal, non-inflamed intestinal mucosa undergo a specific differentiation resulting in a non-reactive, tolerogenic intestinal macrophage (IMAC). Recently we demonstrated the differentiation of MO into an intestinal-like macrophage (MAC) phenotype in vitro in a three-dimensional cell culture model (multi-cellular spheroid or MCS model). In the mucosa of patients with inflammatory bowel disease (IBD) in addition to normal IMAC, a reactive MAC population as well as increased levels of monocyte chemoattractant protein 1 (MCP-1) is found. The aim of this study was to investigate the influence of MCP-1 on the differentiation of MO into IMAC. MCS were generated from adenovirally transfected HT-29 cells overexpressing MCP-1, macrophage inflammatory protein 3 alpha (MIP-3alpha) or non-transfected controls and co-cultured with freshly elutriated blood MO. After 7 days of co-culture MCS were harvested, and expression of the surface antigens CD33 and CD14 as well as the intracellular MAC marker CD68 was determined by flow-cytometry or immunohistochemistry. MCP-1 and MIP-3alpha expression by HT-29 cells in the MCS was increased by transfection at the time of MCS formation. In contrast to MIP-3alpha, MCP-1 overexpression induced a massive migration of MO into the three-dimensional aggregates. Differentiation of IMAC was disturbed in MCP-1-transfected MCS compared to experiments with non-transfected control aggregates, or the MIP-3alpha-transfected MCS, as indicated by high CD14 expression of MO/IMAC cultured inside the MCP-1-transfected MCS, as shown by immunohistochemistry and FACS analysis. Neutralization of MCP-1 was followed by an almost complete absence of monocyte migration into the MCS. MCP-1 induced migration of MO into three-dimensional spheroids generated from HT-29 cells and inhibited intestinal-like differentiation of blood MO into IMAC. It may be speculated that MCP-1 could play a role in the disturbed IMAC differentiation in IBD mucosa

  18. Capillary electrophoresis - electrospray ionization mass spectrometry in small diameter capillaries

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, J.H.; Goodlett, D.R.; Udseth, H.R.; Smith, R.D.

    1992-06-01

    Methods (such as small inner diameter capillaries) are being explored to increase analyte sensitivity in capillary electrophoresis- electrospray ionization/mass spectroscopy(CE-ESI/MS). Results are reported for melittin in a protein mixture, with 10 to 100 {mu}m ID capillaries; and for a mixture of aprotinin, cytochrome c, myoglobin, and carbonic anhydrase, with 5 to 50 {mu}m ID capillaries. It is shown that an increase in solute sensitivity occurs when small ID capillaries ({lt} 20 {mu}m) are used in CE-ESI/MS for both a peptide and a protein mixture. 3 figs. (DLC)

  19. Mechanism and role of MCP-1 upregulation upon chikungunya virus infection in human peripheral blood mononuclear cells.

    Science.gov (United States)

    Ruiz Silva, Mariana; van der Ende-Metselaar, Heidi; Mulder, H Lie; Smit, Jolanda M; Rodenhuis-Zybert, Izabela A

    2016-01-01

    Monocyte chemoattractant protein-1 (MCP-1/CCL2)-mediated migration of monocytes is essential for immunological surveillance of tissues. During chikungunya virus (CHIKV) infection however, excessive production of MCP-1 has been linked to disease pathogenesis. High MCP-1 serum levels are detected during the viremic phase of CHIKV infection and correlate with the virus titre. In vitro CHIKV infection was also shown to stimulate MCP-1 production in whole blood; yet the role and the mechanism of MCP-1 production upon infection of human peripheral blood mononuclear cells remain unknown. Here we found that active CHIKV infection stimulated production of MCP-1 in monocytes. Importantly however, we found that communication with other leukocytes is crucial to yield MCP-1 by monocytes upon CHIKV infection. Indeed, blocking interferon-α/β receptor or the JAK1/JAK2 signalling downstream of the receptor abolished CHIKV-mediated MCP-1 production. Additionally, we show that despite the apparent correlation between IFN type I, CHIKV replication and MCP-1, modulating the levels of the chemokine did not influence CHIKV infection. In summary, our data disclose the complexity of MCP-1 regulation upon CHIKV infection and point to a crucial role of IFNβ in the chemokine secretion. We propose that balance between these soluble factors is imperative for an appropriate host response to CHIKV infection. PMID:27558873

  20. Mechanism and role of MCP-1 upregulation upon chikungunya virus infection in human peripheral blood mononuclear cells

    Science.gov (United States)

    Ruiz Silva, Mariana; van der Ende-Metselaar, Heidi; Mulder, H. Lie; Smit, Jolanda M.; Rodenhuis-Zybert, Izabela A.

    2016-01-01

    Monocyte chemoattractant protein-1 (MCP-1/CCL2)-mediated migration of monocytes is essential for immunological surveillance of tissues. During chikungunya virus (CHIKV) infection however, excessive production of MCP-1 has been linked to disease pathogenesis. High MCP-1 serum levels are detected during the viremic phase of CHIKV infection and correlate with the virus titre. In vitro CHIKV infection was also shown to stimulate MCP-1 production in whole blood; yet the role and the mechanism of MCP-1 production upon infection of human peripheral blood mononuclear cells remain unknown. Here we found that active CHIKV infection stimulated production of MCP-1 in monocytes. Importantly however, we found that communication with other leukocytes is crucial to yield MCP-1 by monocytes upon CHIKV infection. Indeed, blocking interferon-α/β receptor or the JAK1/JAK2 signalling downstream of the receptor abolished CHIKV-mediated MCP-1 production. Additionally, we show that despite the apparent correlation between IFN type I, CHIKV replication and MCP-1, modulating the levels of the chemokine did not influence CHIKV infection. In summary, our data disclose the complexity of MCP-1 regulation upon CHIKV infection and point to a crucial role of IFNβ in the chemokine secretion. We propose that balance between these soluble factors is imperative for an appropriate host response to CHIKV infection. PMID:27558873

  1. A New Height Error Revision Method of Predicting Long-Term Wind Speed with MCP Algorithm

    Science.gov (United States)

    Liu, Yujue; Hu, Fei

    2013-04-01

    Wind energy technology is one of the fastest in growing rate in new and renewable energy technologies. It is very important to select stronger windy sites in a country for the purpose of producing more electricity. Measure-Correlate-Predict (MCP) algorithms are used to predict the wind resource at target site for wind power development. MCP method model bases on a relationship between wind data (speed and direction) measured at the target site and concurrent wind data at reference site nearby. The model is then used with long-term data from the reference site to predict the long-term wind speed and direction distributions at the target site. MCP method is in order to be able to determine the annual energy capture of a wind farm located at the target site. Over the last 15 years well over a half dozen of MCP methods in the literature. The MCP algorithms differ in terms of overall approach, model definition, use of direction sectors, and length of the data. Such as 1)a linear regression model; 2)a model using distributions of ratios of wind speeds at two sites; 3)a vector regression method; 4)a method based on the ratio of standard deviations of two data sets, etc. Unfortunately, none of these MCP algorithms can predict wind speed from two sites at different altitudes. If the target site is much higher or lower than the reference site, the result accuracy will be much poorer. Inner Mongolia grassland is known as one of the regions that rich in wind resource in China. The data we use is from three wind measurements, consisting of nearly one year of six layers in XiLinGuoLe of Inner Mongolia . Firstly, we use the maximum likelihood method to estimate k, shape parameter and c, scale parameter of the Weibull function for different time periods. And then we find out that c has a power law function of height, and that k varies as the form of a quadratic function of height and obtains the max value in the height of 10 to100 meters. Finally, we add the height distribution

  2. Monocyte chemoattractant protein-1 (MCP-1 regulates macrophage cytotoxicity in abdominal aortic aneurysm.

    Directory of Open Access Journals (Sweden)

    Qiwei Wang

    Full Text Available AIMS: In abdominal aortic aneurysm (AAA, macrophages are detected in the proximity of aortic smooth muscle cells (SMCs. We have previously demonstrated in a murine model of AAA that apoptotic SMCs attract monocytes and other leukocytes by producing MCP-1. Here we tested whether infiltrating macrophages also directly contribute to SMC apoptosis. METHODS AND RESULTS: Using a SMC/RAW264.7 macrophage co-culture system, we demonstrated that MCP-1-primed RAWs caused a significantly higher level of apoptosis in SMCs as compared to control macrophages. Next, we detected an enhanced Fas ligand (FasL mRNA level and membrane FasL protein expression in MCP-1-primed RAWs. Neutralizing FasL blocked SMC apoptosis in the co-culture. In situ proximity ligation assay showed that SMCs exposed to primed macrophages contained higher levels of receptor interacting protein-1 (RIP1/Caspase 8 containing cell death complexes. Silencing RIP1 conferred apoptosis resistance to SMCs. In the mouse elastase injury model of aneurysm, aneurysm induction increased the level of RIP1/Caspase 8 containing complexes in medial SMCs. Moreover, TUNEL-positive SMCs in aneurysmal tissues were frequently surrounded by CD68(+/FasL(+ macrophages. Conversely, elastase-treated arteries from MCP-1 knockout mice display a reduction of both macrophage infiltration and FasL expression, which was accompanied by diminished apoptosis of SMCs. CONCLUSION: Our data suggest that MCP-1-primed macrophages are more cytotoxic. MCP-1 appears to modulate macrophage cytotoxicity by increasing the level of membrane bound FasL. Thus, we showed that MCP-1-primed macrophages kill SMCs through a FasL/Fas-Caspase8-RIP1 mediated mechanism.

  3. Influence of Alumina Addition on the Optical Property of Zirconia/Alumina Composite Dental Ceramics

    Institute of Scientific and Technical Information of China (English)

    JIANG Li; LIAO Yunmao; LI Wei; WAN Qianbing; ZHAO Yongqi

    2011-01-01

    The influence of various alumina additions on the optical property of zirconia/alumina composite ceramics was investigated.The relative sintered densities,transmittances,color and the microstructure of the composite ceramics were studied.The experimental results showed that the relative sintered densities and transmittances decreased with alumina addition.The lightness increased obviously but the chroma change was small.Pure zirconia nanopowders sintered densely could obtain the relatively high transmittance,while the transmittance and the lightness of slight addition changed significantly.The zirconia/alumina composite ceramics with alumina addition less than 7.5wt% could achieve the relatively stable and reliable optical properties.

  4. Fracture toughness of advanced alumina ceramics and alumina matrix composites used for cutting tool edges

    OpenAIRE

    M. Szutkowska

    2012-01-01

    Purpose: Specific characteristics in fracture toughness measurements of advanced alumina ceramics and alumina matrix composites with particular reference to α-Al2O3, Al2O3-ZrO2, Al2O3-ZrO2-TiC and Al2O3-Ti(C,N) has been presented.Design/methodology/approach: The present study reports fracture toughness obtained by means of the conventional method and direct measurements of the Vickers crack length (DCM method) of selected tool ceramics based on alumina: pure alumina, alumina-zirconia composit...

  5. Study on the mechanism of radiation-induced MCP-1 expression in RAW264.7 macrophage cells

    International Nuclear Information System (INIS)

    The purpose of this study was to investigate the expression mechanism of MCP-1 in gamma-irradiated RAW 264.7 macrophage cells. MCP-1 plays an important role in attracting monocyte to injured site at the early inflammation stage. However the production mechanism of MCP-1 by gamma-irradiation in RAW 264.7 macrophage cells was almost undiscovered. We found that MCP-1 was produced in RAW 264.7 macrophage cells by irradiation with 5 Gy. And these increases were attenuated by specific inhibitors treatment, such as NF-KB, JNK, ERK, JAK2, and Pyk2. These results indicate that radiation-induced MCP-1 production is mediated by MyD88-and TRIF-dependent pathways in RAW 264.7 macrophage cells. Furthermore, gamma-irradiation induced heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophage cells. However this induction level was reduced before MCP-1 and IFN-β production

  6. Lysophosphatidic Acid Stimulates MCP-1 Secretion from C2C12 Myoblast.

    Science.gov (United States)

    Tsukahara, Tamotsu; Haniu, Hisao

    2012-01-01

    Chemokines are regulatory proteins that play an important role in muscle cell migration and proliferation. In this study, C2C12 cells treated with lysophosphatidic acid (LPA) showed an increase in endogenous monocyte chemotactic protein-1 (MCP-1) expression and secretion. LPA is a naturally occurring bioactive lysophospholipid with hormone- and growth-factor-like activities. LPA is produced by activated platelets, cytokine-stimulated leukocytes, and possibly by other cell types. However, the LPA analog cyclic phosphatidic acid (cPA) had no effect on the expression and secretion of MCP-1. LPA, although similar in structure to cPA, had potent inducing effects on MCP-1 expression in C2C12 cells. In this study, we showed that LPA enhanced MCP-1 mRNA expression and protein secretion in a dose-dependent manner. Taken together, these results suggest that LPA enhances MCP-1 secretion in C2C12 cells and thus may play an important role in cell proliferation. PMID:24049655

  7. Linear attenuation coefficient and build up factor of MCP-96 alloy for radiation shielding and protection

    Science.gov (United States)

    Hopkins, Deidre; Maqbool, Muhammad; Islam, Mohammed

    2009-10-01

    Build-up factors and linear attenuation coefficients of MCP-96 alloy are determined for radiation shielding and protection, using ^60Co and ^137Cs gamma emitters. A narrow collimated beam of γ-rays is passed through various thicknesses of MCP-96 alloy and the attenuation in the intensity of the beam is determined. The thickness of the 4 x 4 cm^2 blocks varies from 0.5 cm to 6 cm. Plotting the thickness of the alloy and the corresponding intensity of the beam allowed us to determine its linear attenuation coefficient. The narrow beam geometry is then replaced by broad beam geometry by removing the collimator and the radiation beam is able to interact with the MCP-96 alloy at all possible positions facing the radiation source. Additional radiations obtained by the detector as a result from the scattering of radiation develops the build-up factor. The buildup factor is then calculated using the attenuated beam received by the detector in the broad beam geometry and in the narrow beam geometry. The buildup factor is found to be dependent on the thickness of the MCP-96 attenuator, the beam energy and the source to attenuator distance. These values are providing ways for dose correction in radiation oncology and radiation shielding and protection when MCP-96 is used as tissue compensator or for radiation protection purposes.

  8. A new design of large area MCP-PMT for the next generation neutrino experiment

    International Nuclear Information System (INIS)

    This manuscript discusses a new design of large area MCP-PMT for the next generation neutrino experiments. The main motivation of the design is to improve the quantum efficiency (photo detection efficiency) of the PMT. Two sets of small MCP units, the transmission photocathode coated on the front hemisphere and the reflection photocathode coated on the rear hemisphere are assembled in the same glass envelope to form nearly 4π viewing angle to enhance the efficiency of the photoelectron detection. The photoelectrons from the 4π photocathode are collected and amplified by two sets of MCP units. Our goal is eventually to produce 20 in. diameter PMT following such an approach. We will report preliminary results of our ptoelectronic simulation and the results of a 5 in. diameter prototype PMT. Future plans and prospects are discussed at the end.

  9. CHANGES IN MECHANICAL PROPERTIES OF MINIMALLY-PROCESSED YELLOW PITAHAYA TREATED WITH 1-MCP

    Directory of Open Access Journals (Sweden)

    LILIANA SERNA COCK

    2012-01-01

    Full Text Available Se evaluaron las propiedades mecánicas de esfuerzo del límite de fluencia (sL, modulo de deformación (Ed, esfuerzo de ruptura (sF, y deformación de Hencky en la ruptura (eHF de muestras de pitahaya amarilla mínimamente procesada y tratadas con 200 μgL-1 de 1-MCP durante el almacenamiento a 10±1 °C y 85% de humedad relativa. Las muestras fueron sometidas a pruebas de compresión uniaxial hasta la ruptura. Los resultados mostraron que las muestras tratadas con 1-MCP presentaron los mayores valores del esfuerzo del límite de fluencia, modulo de elasticidad y esfuerzo de ruptura. Esto indica que la aplicación del 1-MCP proporciona mayor firmeza a la fruta y puede representar una alternativa para disminuir cambios indeseables de textura durante el almacenamiento.

  10. Antigen Presentation Ability of Salmonella Carrying DNA Vaccine Model and MCP-3 gene

    Directory of Open Access Journals (Sweden)

    Endang Winiati Bachtiar

    2015-11-01

    Full Text Available The objective of this study is to determine the antigen presentation ability of a DNA vaccine model that is co-delivered with that of recombinant Salmonella enterica serovar Typhimurium (STM1 expressing chemokine macrophage chemotactic protein-3 (MCP-3. The DNA vaccine, pVROVA, was constructed by amplification of the ovalbumin coding region from sOVA-C1. Dendritic cells (DCs were obtained from IL-4 and GMCSF stimulated mouse bone marrow stem cell. Cultured DCs were incubated with STM1 carrying a model ovalbumin gene (pVROVA. Furthermore, MHC class I antigen presentation of a dominant OVA peptide was assayed in vitro. The experiments were designed to determine the effect of co-delivering MCP-3 with that of ovalbumin in STM1. Our results show that a plasmid pROVA-carrying ovalbumin gene was succesfully constructed and sequence analysis of the ovalbumin-coding revealed an identity match of 100% with that of the chicken ovalbumin DNA sequences from the GenBank database. We also found that the presence of the MCP-3 encoding plasmid in STM1 or E. coli DH1 could increase the recovery of both STM1 and E. coli DH1 over those that carry the empty plasmids. Antigen presentation assay also indicates that MCP-3 can positively influence the presentation of ovalbumin. Conclusion: the infection of DCs by STM1-carrying DNA vaccine and MCP-3 results in an increase of processing and presentation of ovalbumin in vitro.Keywords : DNA vaccine, MCP-3, APC, Salmonella, Dendritic cells

  11. Amadurecimento de bananas 'maçã' submetidas ao 1-metilciclopropeno (1-MCP Ripening of 'apple' banana submitted to 1-methylcyclopropene (1-MCP

    Directory of Open Access Journals (Sweden)

    Ana Carla Marques Pinheiro

    2007-04-01

    Full Text Available Objetivou-se avaliar o efeito do 1-MCP, em diferentes tempos de aplicação, sobre amadurecimento e atributos de qualidade da banana 'Maçã'. Utilizou-se um delineamento experimental inteiramente casualizado (DIC, em esquema fatorial 3x5, ou seja, avaliaram-se as bananas em três diferentes graus de coloração da casca (grau 2: 100% verdes; grau 4: mais amarelas que verdes; grau 7: completamente amarelas, com pontuações marrons e cinco tempos de aplicação de 50 hL.L-1 de 1-MCP (0-controle; 6; 9; 12 e 24 horas. O experimento foi conduzido com três repetições constituídas por três buquês, com quatro frutos cada. Os dados obtidos foram submetidos à análise de variância (ANOVA e ao teste de Tukey, e regressão polinomial, quando conveniente. O 1-MCP foi aplicado nos frutos no grau 2 de coloração da casca, na concentração de 50hL.L-1, a 25±1ºC. Os frutos, após aplicação, foram armazenados a 25±1ºC e 80±5% UR e avaliados, quanto ao teor de sólidos solúveis (SS e açúcares solúveis totais (AST, pH e cor da casca, nos graus 2; 4 e 7 de coloração e também a taxa respiratória, que foi acompanhada diariamente. A aplicação de 50nL.L-1 de 1-MCP atrasou o início do amadurecimento de bananas 'Maçã', conforme as primeiras mudanças visíveis na coloração da casca de verde para amarela, em aproximadamente 9 dias. Observou-se também retardo na ascensão e diminuição da taxa respiratória, de aproximadamente 50%, no ponto máximo do climatério, nos frutos submetidos ao 1-MCP, durante o amadurecimento. O 1-MCP a 50hL.L-1, em qualquer tempo de aplicação, retardou o amadurecimento de bananas 'Maçã' sem afetar os atributos de qualidade valor b* (cor da casca, os teores de sólidos solúveis, açúcares solúveis totais e pH.This work aimed to evaluate the effect of 1-MCP, at different of application times, under ripening and quality attributes of 'Apple' banana. The experiment was carried out in a completely randomized

  12. A 30 ps Timing Resolution for Single Photons with Multi-pixel Burle MCP-PMT

    Energy Technology Data Exchange (ETDEWEB)

    Va' vra, J.; Benitez, J.; Coleman, J.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.; Schwiening, J.; /SLAC

    2006-07-05

    We have achieved {approx}30 psec single-photoelectron and {approx}12ps for multi-photoelectron timing resolution with a new 64 pixel Burle MCP-PMT with 10 micron microchannel holes. We have also demonstrated that this detector works in a magnetic field of 15kG, and achieved a single-photoelectron timing resolution of better than 60 psec. The study is relevant for a new focusing DIRC RICH detector for particle identification at future Colliders such as the super B-factory or ILC, and for future TOF techniques. This study shows that a highly pixilated MCP-PMT can deliver excellent timing resolution.

  13. MCP-based detector in the Magnetic Field: Some results and perspectives

    CERN Document Server

    Patarakin, O O; CERN. Geneva; Kartamushev, A A; Tikhonov, V N

    1997-01-01

    This paper presents the experimental results of the MCP-based detector timing resolution studying. The timing resolution of shevron-type MCP-detector was obtained =82±2 ps as without magnetic field as with longitudinal magnetic field at 1.5 kG. It was shown that a deterioration of a timing resolution in this field is smaller than 20 ps. The timing resolution =31±2 ps had been obtained for thin (10%) amplitude spectrum

  14. Wound Healing in MIP-1α−/− and MCP-1−/− Mice

    OpenAIRE

    Low, Quentin E. H.; Drugea, Iulia A.; Duffner, Lisa A.; Quinn, Daniel G.; Cook, Donald N.; Rollins, Barrett J.; Kovacs, Elizabeth J.; DiPietro, Luisa A.

    2001-01-01

    A salient feature of normal wound healing is the development and resolution of an acute inflammatory response. Although much is known about the function of inflammatory cells within wounds, little is known about the chemotactic and activation signals that influence this response. As the CC chemokines macrophage inflammatory protein-1α (MIP-1α) and monocyte chemotactic protein-1 (MCP-1) are abundant in acute wounds, wound repair was examined in MIP-1α−/− and MCP-1−/− mice. Surprisingly, wound ...

  15. Characterization and application of electrospun alumina nanofibers

    Science.gov (United States)

    2014-01-01

    Alumina nanofibers were prepared by a technique that combined the sol–gel and electrospinning methods. The solution to be electrospun was prepared by mixing aluminum isopropoxide (AIP) in ethanol, which was then refluxed in the presence of an acid catalyst and polyvinylpyrolidone (PVP) in ethanol. The characterization results showed that alumina nanofibers with diameters in the range of 102 to 378 nm were successfully prepared. On the basis of the results of the XRD and FT-IR, the alumina nanofibers calcined at 1,100°C were identified as comprising the α-alumina phase, and a series of phase transitions such as boehmite → γ-alumina → α-alumina were observed from 500°C to 1,200°C. The pore size of the obtained γ-alumina nanofibers is approximately 8 nm, and it means that they are mesoporous materials. The kinetic study demonstrated that MO adsorption on alumina nanofibers can be seen that the pseudo-second-order kinetic model fits better than the pseudo-first-order kinetic model. PMID:24467944

  16. MECHANISMS OF INITIAL SINTERING OF A FINE ALUMINA POWDER

    OpenAIRE

    S. Raman; Doremus, R.; R. German

    1986-01-01

    The mechanism of initial sintering of alumina was explored by electron microscopy and X-ray diffraction. The transformation of gamma to alpha alumina influenced sintering behavior. This transformation appears to involve plastic deformation in the alumina. Sintering of fine alpha alumina powder directly occurs with an activation energy close to that of grain boundary diffusion of oxygen.

  17. Dissolution Kinetics of Alumina Calcine

    Energy Technology Data Exchange (ETDEWEB)

    Batcheller, Thomas Aquinas

    2001-09-01

    Dissolution kinetics of alumina type non-radioactive calcine was investigated as part of ongoing research that addresses permanent disposal of Idaho High Level Waste (HLW). Calcine waste was produced from the processing of nuclear fuel at the Idaho Nuclear Technology and Engineering Center (INTEC). Acidic radioactive raffinates were solidified at ~500°C in a fluidized bed reactor to form the dry granular calcine material. Several Waste Management alternatives for the calcine are presented in the Idaho High Level Waste Draft EIS. The Separations Alternative addresses the processing of the calcine so that the HLW is ready for removal to a national geological repository by the year 2035. Calcine dissolution is the key front-end unit operation for the separations alternative.

  18. Alumina forming iron base superalloy

    Science.gov (United States)

    Yamamoto, Yukinori; Muralidharan, Govindarajan; Brady, Michael P.

    2014-08-26

    An austenitic stainless steel alloy, consists essentially of, in weight percent 2.5 to 4 Al; 25 to 35 Ni; 12 to 19 Cr; at least 1, up to 4 total of at least one element selected from the group consisting of Nb and Ta; 0.5 to 3 Ti; less than 0.5 V; 0.1 to 1 of at least on element selected from the group consisting of Zr and Hf; 0.03 to 0.2 C; 0.005 to 0.1 B; and base Fe. The weight percent Fe is greater than the weight percent Ni. The alloy forms an external continuous scale including alumina, and contains coherent precipitates of .gamma.'-Ni.sub.3Al, and a stable essentially single phase FCC austenitic matrix microstructure. The austenitic matrix is essentially delta-ferrite-free and essentially BCC-phase-free.

  19. Alumina Thin Film Growth: Experiments and Modeling

    OpenAIRE

    Wallin, Erik

    2007-01-01

    The work presented in this thesis deals with experimental and theoretical studies related to the growth of crystalline alumina thin films. Alumina, Al2O3, is a polymorphic material utilized in a variety of applications, e.g., in the form of thin films. Many of the possibilities of alumina, and the problems associated with thin film synthesis of the material, are due to the existence of a range of different crystalline phases. Controlling the formation of the desired phase and the transformati...

  20. Characterization and application of electrospun alumina nanofibers

    OpenAIRE

    Kim, Jeon-Hee; Yoo, Seung-Joon; Kwak, Dong-Heui; Jung, Heung-Joe; KIM, Tae-Young; Park, Kyung-Hee; Lee, Jae-Wook

    2014-01-01

    Alumina nanofibers were prepared by a technique that combined the sol–gel and electrospinning methods. The solution to be electrospun was prepared by mixing aluminum isopropoxide (AIP) in ethanol, which was then refluxed in the presence of an acid catalyst and polyvinylpyrolidone (PVP) in ethanol. The characterization results showed that alumina nanofibers with diameters in the range of 102 to 378 nm were successfully prepared. On the basis of the results of the XRD and FT-IR, the alumina nan...

  1. Capillary permeability in adipose tissue

    DEFF Research Database (Denmark)

    Paaske, W P; Nielsen, S L

    1976-01-01

    A method for measurement of capillary permeability using external registration of gamma emitting isotopes after close arterial bolus injection was applied to the isolated inguinal fat pad in slightly fasting rabbits. An average extraction of 26 per cent for 51Cr-EDTA was found at a plasma flow of...... about 7 ml/100 g-min. This corresponds to a capillary diffusion capacity of 2.0 ml/100 g-min which is half the value reported for vasodilated skeletal muscle having approximately twice as great capillary surface area. Thus, adipose tissue has about the same capillary permeability during slight metabolic...

  2. Fast plasma discharge capillary design as a high power throughput soft x-ray emission source

    Energy Technology Data Exchange (ETDEWEB)

    Wyndham, E. S.; Favre, M.; Valdivia, M. P.; Valenzuela, J. C.; Chuaqui, H.; Bhuyan, H. [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Ave. Vicuna Mackenna 4860, Santiago (Chile)

    2010-09-15

    We present the experimental details and results from a low energy but high repetition rate compact plasma capillary source for extreme ultraviolet and soft x-ray research and applications. Two lengths of capillary are mounted in two versions of a closely related design. The discharge operates in 1.6 and 3.2 mm inner diameter alumina capillaries of lengths 21 and 36 mm. The use of water both as dielectric and as coolant simplifies the compact low inductance design with nanosecond discharge periods. The stored electrical energy of the discharge is approximately 0.5 J and is provided by directly charging the capacitor plates from an inexpensive insulated-gate bipolar transistor in 1 {mu}s or less. We present characteristic argon spectra from plasma between 30 and 300 A as well as temporally resolved x-ray energy fluence in discrete bands on axis. The spectra also allow the level of ablated wall material to be gauged and associated with useful capillary lifetime according to the chosen configuration and energy storage. The connection between the electron beams associated with the transient hollow cathode mechanism, soft x-ray output, capillary geometry, and capillary lifetime is reported. The role of these e-beams and the plasma as measured on-axis is discussed. The relation of the electron temperature and the ionization stages observed is discussed in the context of some model results of ionization in a non-Maxwellian plasma.

  3. Recent Development of High Alumina Refractories in China

    Institute of Scientific and Technical Information of China (English)

    WANGJin-xiang; LIUJie-hua

    1994-01-01

    The paper reviews the achievements which have been attained recently in China in high alumina refractories raw materials and their products,including 1) homogenization ,urification and electric fusion of high alumina raw materials and synthesizing of spinel from natural raw materials;2) processing principle and characteristics and microstructural features of creep-resistance high alu-mina brick ,alumina-magnesia-carbon brick and thermal shock resistanced high alumina brikc and their application in practice.

  4. Influence of sulphur impurities on the interfacial tension between aluminium and cryolite alumina melts

    Energy Technology Data Exchange (ETDEWEB)

    Korenko, M. [Slovak Academy of Sciences, Bratislava (Slovakia). Dept. of Inorganic Chemistry

    2007-05-15

    The interfacial tension (IFT) between aluminium and cryolite melts containing different salt additions (AlF{sub 3}, NaF,Na{sub 2}SO{sub 4}) has been measured during electrolysis by the capillary depression method. The technique is based on the measurement of the capillary depression occurring when a capillary, which is moved vertically down through the molten salt layer, passes through the metal/salt interface. The depression is measured by simultaneous video recording of the immersion height of the alumina capillary. The interfacial tension is strongly dependent on the n(NaF)/n(AlF{sub 3}) ratio. The addition of Na{sub 2}SO{sub 4} decreases the IFT of the aluminium/electrolyte interface. We also found the different influence of the conditions of electrolysis on the IFT in systems with and without Na{sub 2}SO{sub 4}. In systems without Na{sub 2}SO{sub 4} the IFT decreases with increasing current density, and in systems with Na{sub 2}SO{sub 4} it increases. (orig.)

  5. Influence of 1-MCP treatments on eating quality and consumer preferences of ‘Qinmei’ kiwifruit during shelf life

    Science.gov (United States)

    Consumers and growers in China sometime complain that Kiwifruits treated with an ethylene action inhibitor 1-MCP are difficult to ripen and show poor eating quality. This study addresses the quality parameters affecting consumer preferences and reevaluates the necessity of 1-MCP application for stor...

  6. Macrophage Migration Inhibitor Factor Upregulates MCP-1 Expression in an Autocrine Manner in Hepatocytes during Acute Mouse Liver Injury

    Science.gov (United States)

    Xie, Jieshi; Yang, Le; Tian, Lei; Li, Weiyang; Yang, Lin; Li, Liying

    2016-01-01

    Macrophage migration inhibitor factor (MIF), a multipotent innate immune mediator, is an upstream component of the inflammatory cascade in diseases such as liver disease. Monocyte chemoattractant protein-1 (MCP-1), a highly representative chemokine, is critical in liver disease pathogenesis. We investigated the role of MIF in regulating hepatocytic MCP-1 expression. MIF and MCP-1 expression were characterized by immunochemistry, RT-PCR, ELISA, and immunoblotting in CCl4-treated mouse liver and isolated hepatocytes. MIF was primarily distributed in hepatocytes, and its expression increased upon acute liver injury. Its expression was also increased in injured hepatocytes, induced by LPS or CCl4, which mimic liver injury in vitro. MIF was expressed earlier than MCP-1, strongly inducing hepatocytic MCP-1 expression. Moreover, the increase in MCP-1 expression induced by MIF was inhibited by CD74- or CD44-specific siRNAs and SB203580, a p38 MAPK inhibitor. Further, CD74 or CD44 deficiency effectively inhibited MIF-induced p38 activation. MIF inhibitor ISO-1 reduced MCP-1 expression and p38 phosphorylation in CCl4-treated mouse liver. Our results showed that MIF regulates MCP-1 expression in hepatocytes of injured liver via CD74, CD44, and p38 MAPK in an autocrine manner, providing compelling information on the role of MIF in liver injury, and implying a new regulatory mechanism for liver inflammation. PMID:27273604

  7. Optimization of the electron collection efficiency of a large area MCP-PMT for the JUNO experiment

    Science.gov (United States)

    Chen, Lin; Tian, Jinshou; Liu, Chunliang; Wang, Yifang; Zhao, Tianchi; Liu, Hulin; Wei, Yonglin; Sai, Xiaofeng; Chen, Ping; Wang, Xing; Lu, Yu; Hui, Dandan; Guo, Lehui; Liu, Shulin; Qian, Sen; Xia, Jingkai; Yan, Baojun; Zhu, Na; Sun, Jianning; Si, Shuguang; Li, Dong; Wang, Xingchao; Huang, Guorui; Qi, Ming

    2016-08-01

    A novel large-area (20-inch) photomultiplier tube based on microchannel plate (MCP-PMTs) is proposed for the Jiangmen Underground Neutrino Observatory (JUNO) experiment. Its photoelectron collection efficiency Ce is limited by the MCP open area fraction (Aopen). This efficiency is studied as a function of the angular (θ), energy (E) distributions of electrons in the input charge cloud and the potential difference (U) between the PMT photocathode and the MCP input surface, considering secondary electron emission from the MCP input electrode. In CST Studio Suite, Finite Integral Technique and Monte Carlo method are combined to investigate the dependence of Ce on θ, E and U. Results predict that Ce can exceed Aopen, and are applied to optimize the structure and operational parameters of the 20-inch MCP-PMT prototype. Ce of the optimized MCP-PMT is expected to reach 81.2%. Finally, the reduction of the penetration depth of the MCP input electrode layer and the deposition of a high secondary electron yield material on the MCP are proposed to further optimize Ce.

  8. Burned Microporous Alumina-Graphite Brick

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ 1 Scope This standard specifies the definition,classifica-tion,technical requirements,test methods,inspection rules,marking,packing,transportation and quality certificate of burned microporous alumina-graphite brick.

  9. Acoustic Emission and Damage Characteristics of Alumina

    Institute of Scientific and Technical Information of China (English)

    REN Hui-lan; NING Jian-guo; HE Jian-hua

    2009-01-01

    gy, AE counts, AE amplitude changing with loading time are analyzed for the notched alumina specimen. It is indicated that AE characteristic parameters reflect the damage process and fracture of material.

  10. Loss tangent measurements on unirradiated alumina

    Energy Technology Data Exchange (ETDEWEB)

    Zinkle, S.J.; Goulding, R.H. [Oak Ridge National Lab., TN (United States)

    1996-04-01

    Unirradiated room temperature loss tangent for sapphire and several commercial grades of polycrystalline alumina are complied for frequencies between 10{sup 5} and 4x10{sup 11} Hz. Sapphire exhibits significantly lower values for the loss tangent at frequencies up to 10{sup 11} Hz. The loss tangents of 3 different grades of Wesgo alumina (AL300, AL995, AL998) and 2 different grades of Coors alumina (AD94, AD995) have typical values near {approx}10{sup -4} at a frequency of 10{sup 8} Hz. On the other hand, the loss tangent of Vitox alumina exhibits a large loss peak tan d{approx} 5x10{sup -3} at this frequency.

  11. Evaluating the potential of IP-10 and MCP-2 as biomarkers for the diagnosis of TB

    DEFF Research Database (Denmark)

    Ruhwald, Morten; Bodmer, T; Maier, C;

    2008-01-01

    were obtained from 80 patients with culture and/or PCR proven TB, and 124 unexposed healthy controls; 86 high school students and 38 high school staff. IP-10 and MCP-2 test cut-offs were established based on ROC curve analysis.TB patients produced significantly higher levels of IP-10 (median 2158 pg.......ml(-1)) and MCP-2 (median 379 pg.ml(-1)) compared with IFN-gamma (median 215 pg.ml(-1), p<0.0001). The QFT-IT, IP-10 and MCP-2 tests detected 81%, 83% and 71% of the TB patients; 0%, 3% and 0% of the high school students and 0%, 16%; and 3% of the staff. Agreement between tests was high >89% (kappa>0.......77). By combining IP-10 and IFN-gamma tests the detection rate increased among TB patients to 90% without a significant increase in positive responders among the students.In conclusion, IP-10 and MCP-2 responses to M.tuberculosis specific antigens could be used to diagnose infection. Combining IP-10 and...

  12. Microchannel plate (MCP) focusing optics for a repetitive laser-plasma source

    International Nuclear Information System (INIS)

    The authors describe the use of microchannel plate (MCP) optics to focus soft X-rays produced by the Rutherford Appleton Laboratory (RAL) high brightness plasma source. In this source the X-ray emitting plasma is generated by a high repetition rate, picosecond pulsed excimer laser system. A low cost, low debris, high intensity soft X-ray beamline results from the combination of this bright, point-like, plasma source with a planar square-pore MCP optic. Fluxes of 9 x 109 photon/mm2/s at 33.7 angstrom wavelength and 4 x 107 photon/mm2/s at 7.8 angstrom wavelength have been recorded at the MCP focus. This paper also describes the exploitation of the RAL source for the characterization of prototype MCP optics. Investigations into both planar MCPs with square pores and spherically slumped MCPs with circular pores are reported. The small (10microm diameter) size of the plasma source coupled with an ability to make absolute flux measurements greatly facilitates the calibration process

  13. Study of Background Characteristics of CEM, MCP and PMT Detectors at n-g Irradiation

    OpenAIRE

    Garcia, Francisco; Kozlovsky, Stanislav; Balin, Dmitri

    2000-01-01

    This paper presents the results of measurements of sensitivity of the registering elements of particle detectors for plasma diagnostics, the Channel Electron Multipliers (CEM), the MicroChannel Plate (MCP) and Photomultipliers (PMT) to neutron and gamma radiation and estimates of intensity level which can cease their operation.

  14. 1996 'STELLAR' and MCP summer programs commencement. Apollo Astronaut Buzz Aldren drops by after

    Science.gov (United States)

    1996-01-01

    1996 'STELLAR' and MCP summer programs commencement. Apollo Astronaut Buzz Aldren drops by after attending his book signing at US Space Camp eariler in the day is shown here with Gayle Wilson (governor's wife) and Ken Munechika (R) and Dr. Rose Grymes (center)

  15. Aging and serum MCP-1 are associated with gut microbiome composition in a murine model.

    Science.gov (United States)

    Conley, Melissa N; Wong, Carmen P; Duyck, Kyle M; Hord, Norman; Ho, Emily; Sharpton, Thomas J

    2016-01-01

    Introduction. Age is the primary risk factor for major human chronic diseases, including cardiovascular disorders, cancer, type 2 diabetes, and neurodegenerative diseases. Chronic, low-grade, systemic inflammation is associated with aging and the progression of immunosenescence. Immunosenescence may play an important role in the development of age-related chronic disease and the widely observed phenomenon of increased production of inflammatory mediators that accompany this process, referred to as "inflammaging." While it has been demonstrated that the gut microbiome and immune system interact, the relationship between the gut microbiome and age remains to be clearly defined, particularly in the context of inflammation. The aim of our study was to clarify the associations between age, the gut microbiome, and pro-inflammatory marker serum MCP-1 in a C57BL/6 murine model. Results. We used 16S rRNA gene sequencing to profile the composition of fecal microbiota associated with young and aged mice. Our analysis identified an association between microbiome structure and mouse age and revealed specific groups of taxa whose abundances stratify young and aged mice. This includes the Ruminococcaceae, Clostridiaceae, and Enterobacteriaceae. We also profiled pro-inflammatory serum MCP-1 levels of each mouse and found that aged mice exhibited elevated serum MCP-1, a phenotype consistent with inflammaging. Robust correlation tests identified several taxa whose abundance in the microbiome associates with serum MCP-1 status, indicating that they may interact with the mouse immune system. We find that taxonomically similar organisms can exhibit differing, even opposite, patterns of association with the host immune system. We also find that many of the OTUs that associate with serum MCP-1 stratify individuals by age. Discussion. Our results demonstrate that gut microbiome composition is associated with age and the pro-inflammatory marker, serum MCP-1. The correlation between age

  16. Reactivity of non-stoichiometric black alumina

    International Nuclear Information System (INIS)

    Oxides such as alumina, when divided or poorly crystallized, show enhanced physico-chemical properties with respect to those of non-divided crystals of the same solids. A stoichiometric difference may even be produced in the alumina, which brings about a new modification of its properties. However its characteristics of hydrogen chemisorption or of catalytic activity in ethylene hydrogenation do not appear to depend on the stoichiometric difference. (author)

  17. Point defects in alumina studied by thermoluminescence

    OpenAIRE

    Papin, Eric; Grosseau, Philippe; Guilhot, Bernard; Benabdesselam, Mourad; Iacconi, Philibert

    1997-01-01

    Alpha alumina powders have been produced by thermal treatment under controlled atmosphere of highly pure gamma alumina. The influence of the atmosphere and the addition of dopants (Mg2+, Cr3+, Th4+) were studied by thermoluminescence (TL). TL is a technique which gives information about point defects. It allowed to reveal the presence of oxygen and aluminium vacancies. The sintering of undoped powders prepared under different atmosphere was investigated by dilatometry. Powders prepared under ...

  18. Dissolution of alumina in stainless steelmaking slags

    Energy Technology Data Exchange (ETDEWEB)

    Divakar, M.; Lahiri, A.K. [Indian Inst. of Science, Bangalore (India). Dept. of Metallurgy; Goernerup, M. [Uddeholm Technology AB (Sweden)

    2001-02-01

    Dissolution of alumina in stainless steelmaking slags was studied by conducting laboratory scale experiments on typical slags in the temperature range 1823-1923 K. The mechanism of dissolution was studied under the actual steelmaking conditions where several phenomena such as simultaneous reduction of chromium, iron and vanadium oxides by carbon, in-situ gas generated due to the reduction, foam/emulsion formation occur. The kinetics of alumina dissolution are studied under the influence of the above mentioned phenomena. (orig.)

  19. Monitoring Transport Across Modified Nanoporous Alumina Membranes

    OpenAIRE

    Steinle, Erich D.; Andrew L. Molder; Hardin, Jonathan L.; Ravikanth Kona; Penumetcha, Sai S.

    2007-01-01

    This paper describes the use of several characterization methods to examine alumina nanotubule membranes that have been modified with specific silanes. The function of these silanes is to alter the transport properties through the membrane by changing the local environment inside the alumina nanotube. The presence of alkyl groups, either long (C18) or short and branched (isopropyl) hydrocarbon chains, on these silanes significantly decreases the rate of transport of permeant molecules through...

  20. Silicide characterization at alumina-niobium interfaces

    OpenAIRE

    McKeown, JT; Radmilovic, Velimir R; Gronsky, R.; Glaeser, AM

    2011-01-01

    Alumina–niobium interfaces formed by liquidfilm-assisted joining with copper/niobium/copper interlayers exhibited microstructures that depend on the nature of the alumina components. Characterization of these interfaces in the transmission electron microscope provided insight on the relationship between interfacial microstructure and fracture performance. Interfaces between sapphire and niobium and those between high-purity (99.9%) polycrystalline alumina and niobium were free of secondary ph...

  1. Tapered capillary optics

    Science.gov (United States)

    Hirsch, Gregory

    1998-01-01

    A metal or glass wire is etched with great precision into a very narrowly tapering cone which has the shape of the desired final capillary-optics bore. By controlling the rate of removal of the wire from an etchant bath, a carefully controlled taper is produced. A sensor measures the diameter of the wire as it leaves the surface of the etchant. This signal is used for feedback control of the withdrawal speed. The etched wire undergoes a treatment to produce an extremely low surface-roughness. The etched and smoothed wire is coated with the material of choice for optimizing the reflectivity of the radiation being focused. This could be a vacuum evaporation, sputtering, CVD or aqueous chemical process. The coated wire is either electroplated, built up with electroless plating, or encapsulated in a polymer cylinder such as epoxy to increase the diameter of the wire for easier handling and greater robustness. During this process, the wire is vertically oriented and tensioned to assure that the wire is absolutely straight. The coated and electroformed wire is bonded to a flat, rigid substrate and is then periodically segmented by cutting or etching a series of narrow slits or grooves into the wire. The wire is vertically oriented and tensioned during the bonding process to assure that it is straight. The original wire material is then chemically etched away through the slits or otherwise withdrawn to leave the hollow internal bore of the final tapered-capillary optical element.

  2. Alumina Recovery from Kaolin with Mineral Impurities

    Institute of Scientific and Technical Information of China (English)

    SI Peng; QIAO Xiuchen; YU Jianguo

    2012-01-01

    The alumina recovery from low grade kaolin (K-JS) treated through thermal and mechanical methods was investigated.High grade kaolin (K-SX) was used as comparison.The optimum calcination temperatures for K-JS and K-SX were both 600 ℃,which resulted in 89.34wt% of alumina extraction from K-JS and 83.37wt% from K-SX.With the increase in calcination temperature,the chemical reactivity of calcined K-JS and K-SX to acid decreased.Mechanical treatment was much more effective in increasing the alumina extraction from activated kaolin.Around 99wt% of alumina was extracted from K-JS ground for 10 hours and 95wt% of alumina was extracted from K-SX ground for 20 hours.The IR results showed that the substitute of Al for Si occurred in calcined K-SX,however,the impurities in K-JS decreased this substitute.More alumina could be extracted from low grade kaolin than that from high grade kaolin under identical thermal or mechanical conditions.

  3. The kinetics of VEGF and MCP-1 in the second vitrectomy cases with proliferative diabetic retinopathy.

    Science.gov (United States)

    Sassa, Y; Yoshida, S; Ishikawa, K; Asato, R; Ishibashi, T; Kono, T

    2016-05-01

    PurposeTo determine whether the concentrations of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein (MCP)-1 in the vitreous changed after vitrectomy in patients with proliferative diabetic retinopathy (PDR).ParticipantsTwenty-one eyes of 21 patients who needed a second surgery for PDR were included. The reasons for the second surgery were tractional retinal detachment (TRD), neovascular glaucoma, persistent vitreous hemorrhage, macular pucker, and secondary intraocular lens (IOL) implant.MethodsWe measured the VEGF and MCP-1 levels using sandwich enzyme-linked immunosorbent assays in vitreous samples collected from patients with PDR before pars plana vitrectomy (without IOL implantation), and from the same patients during the second surgery.ResultsThere was not significant change in mean VEGF concentrations when comparing first (0.81±0.88 ng/ml) and second surgeries (1.09±1.51 ng/ml). The MCP-1 level was significantly elevated at the time of second surgery (2.20±2.21 ng/ml) compared with the first vitrectomy (0.72±0.57 ng/ml). The MCP-1 levels of the second surgery cases with TRD (3.18±2.27 ng/ml) increased significantly compared with those with other complications (1.72±2.10 ng/ml).ConclusionsAt the second vitrectomy, VEGF did not change significantly in the vitreous of the patients examined. The MCP-1 concentration was markedly elevated at the second vitrectomy, implying an association between the prolonged inflammation after vitrectomy and complications, especially TRD. PMID:26915745

  4. Biomedical applications of capillary electrophoresis

    Science.gov (United States)

    Kartsova, L. A.; Bessonova, E. A.

    2015-08-01

    The review deals with modern analytical approaches used in capillary electrophoresis for solving medical and biological problems: search for biomarkers of various diseases and rapid diagnosis based on characteristic profiles of biologically active compounds by capillary electrophoresis with mass spectrometric detection; monitoring of the residual drugs in biological fluids for evaluating the efficiency of drug therapy; testing of the enantiomeric purity of pharmaceutical products; the use of novel materials as components of stationary and pseudo-stationary phases in capillary electrophoresis and capillary electrochromatography to increase the selectivity of separation of components of complex matrices; and identification of various on-line preconcentration techniques to reduce the detection limits of biologically active analytes. A topical trend in capillary electrophoresis required in clinical practice, viz., the design of microfluidic systems, is discussed. The bibliography includes 173 references.

  5. Capillary optics for radiation focusing

    International Nuclear Information System (INIS)

    Capillary lens technology may ultimately bring benefits to neutron and x-ray-based science like conventional lenses with visible light. Although the technology is not yet 10 years old, these lenses have already had a significant impact in engineering, science, and medicine. Capillary lenses are advantageous when it is desirable to increase the radiation flux at a location without regard to its angular divergence. PNNL has worked to improve the technology in several ways. A single, optimally tapered capillary was manufactured, which allows intensity gains of a factor of 270 for an initially parallel, incident x-ray beam. Feasibility of constructing neutron lenses using 58Ni (particularly effective at reflecting neutrons) has been explored. Three applications for capillary optics have been identified and studied: neutron telescope, Gandolphi x-ray diffractometry, and neutron radiotherapy. A brief guide is given for determining which potential applications are likely to be helped by capillary optics

  6. Influência do etileno e do 1-MCP na senescência e longevidade das inflorescências de esporinha Influence of ethylene and 1-MCP on senescence and longevity of Consolida ajacis inflorescences

    Directory of Open Access Journals (Sweden)

    Vanessa Rebouças dos Santos

    2005-01-01

    Full Text Available A aplicação de etileno e do 1-metilciclopropeno (1-MCP têm efeitos marcantes sobre a abscisão e a longevidade em vaso das inflorescências de esporinha (Consolida ajacis. O etileno acelerou a abscisão das flores em concentrações iguais ou superiores a 1,0 mg L-1 de Ethrel quando pulverizado por duas horas em intervalos de 30 minutos. As concentrações de 100 e 1.000 mg L-1 de Ethrel induziram imediata abscisão das flores, reduzindo a longevidade de 4,4 dias nas flores-controle para 1,8 e 1,2 dias respectivamente. O tratamento com 1-MCP (0,5 g m-3 de SmartFreshTM foi eficiente em retardar o início da abscisão das flores, mesmo quando 100 mg L-1 Ethrel foi pulverizado imediatamente após a aplicação do 1-MCP. Flores tratadas exclusivamente com 1-MCP ou tratadas antes do Ethrel tiveram a longevidade estendida em 33% em relação ao controle. Houve redução da eficiência do 1-MCP, em estender a longevidade, se aplicado após a pulverização com Ethrel, comparado com o tratamento de 1-MCP isoladamente ou 1-MCP seguido de Ethrel. Esse efeito demonstra que 1-MCP não foi capaz de bloquear completamente os receptores do etileno.Ethylene and 1-methylcyclopropene (1-MCP had strong influence on the Consolida ajacis flower abscission and longevity. Ethylene was able to induce abscission of the flowers in concentrations equal or above 1,0 mg L-1 Ethrel, when sprayed over two hours at 30 minutes interval. Concentrations of 100 and 1000 mg L-1 Ehtrel induced fast flower abscission, reducing the longevity from 4.4 days on the control flowers to 1.8 and 1.2 days, respectively. Treatment with 1-MCP (0.5 g m-3 SmartFreshTM was efficient in delaying the beginning of flower abscission, even when the inflorescences were sprayed with 100 mg L-1 Ethrel just after the 1-MCP treatment. Flowers treated exclusively with 1-MCP had the longevity extended in 33% as compared to the control treatment. Similar results were observed when the flowers were treated

  7. Advances in capillary electrophoresis

    International Nuclear Information System (INIS)

    In the 1980s, capillary electrophoresis (CE) developed rapidly into a first-class analytical separation technique. Its advances in instru-mentation and method development will not only enhance or complement existing mature separation techniques such as liquid chromatography and conventional slab gel electrophoresis, but will also severely challenge these separation methods. A brief overview of most striking achievement of CE in the 1980s is given, which illustrates the challenge to liquid chromatography and conventional slab gel electrophoresis, and some detailed discussions are presented to highlight the advantages of CE. New developments in CE that can be expected for the 1990s include especially column technology, separation chemistry and instrumentation, which will serve further to diversify and improve the applicability of this technique in areas which are poorly addressed by other separation methods. This paper considers and speculates on the technological advancements that can be expected to emerge for CE in the 1990s. (author). 95 refs.; 14 figs

  8. Influência do 1-MCP na conservação pós-colheita de rosas cv. Vega Influence of 1-MCP on postharvest conservation of roses cv. Vega

    OpenAIRE

    Júlia De Pietro; Ben-Hur Mattiuz; Claudia Fabrino Machado Mattiuz

    2010-01-01

    Objetivou-se, neste trabalho, estudar aspectos da fisiologia pós-colheita de rosas cortadas cv. Vega, tratadas com diferentes concentrações de 1-metilcicloropropeno (1-MCP). O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial composto por dois fatores: quatro tratamentos pós-colheita e quatro datas de avaliação (0; 4; 8; 12 dias). As flores foram submetidas aos seguintes tratamentos: 1) Água destilada (controle); 2) 1-MCP (100 ppb); 3) 1-MCP (250 ppb); 4)...

  9. Toward a noncytotoxic glioblastoma therapy: blocking MCP-1 with the MTZ Regimen

    Directory of Open Access Journals (Sweden)

    Salacz ME

    2016-04-01

    Full Text Available Michael E Salacz,1,2 Richard E Kast,3 Najmaldin Saki,4 Ansgar Brüning,5 Georg Karpel-Massler,6 Marc-Eric Halatsch6 1Department of Internal Medicine, 2Department of Neurosurgery, University of Kansas, Kansas City, KS, USA; 3IIAIGC Study Center, Burlington, VT, USA; 4Health Research Institute, Research Center of Thalassemia and Hemoglobinopathy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 5Molecular Biology Laboratory, University Hospital Munich, Munich, Germany; 6Department of Neurosurgery, University of Ulm, Ulm, Germany Abstract: To improve the prognosis of glioblastoma, we developed an adjuvant treatment directed to a neglected aspect of glioblastoma growth, the contribution of nonmalignant monocyte lineage cells (MLCs (monocyte, macrophage, microglia, dendritic cells that infiltrated a main tumor mass. These nonmalignant cells contribute to glioblastoma growth and tumor homeostasis. MLCs comprise of approximately 10%–30% of glioblastoma by volume. After integration into the tumor mass, these become polarized toward an M2 immunosuppressive, pro-angiogenic phenotype that promotes continued tumor growth. Glioblastoma cells initiate and promote this process by synthesizing 13 kDa MCP-1 that attracts circulating monocytes to the tumor. Infiltrating monocytes, after polarizing toward an M2 phenotype, synthesize more MCP-1, forming an amplification loop. Three noncytotoxic drugs, an antibiotic – minocycline, an antihypertensive drug – telmisartan, and a bisphosphonate – zoledronic acid, have ancillary attributes of MCP-1 synthesis inhibition and could be re-purposed, singly or in combination, to inhibit or reverse MLC-mediated immunosuppression, angiogenesis, and other growth-enhancing aspects. Minocycline, telmisartan, and zoledronic acid – the MTZ Regimen – have low-toxicity profiles and could be added to standard radiotherapy and temozolomide. Re-purposing older drugs has advantages of established safety and low

  10. Solvent mediated assembly of nanoparticles confined in mesoporous alumina.

    Energy Technology Data Exchange (ETDEWEB)

    Alvine, K. J.; Pontoni, D.; Shpyrko, O. G.; Pershan, P. S.; Cookson, D. J.; Shin, K.; Russell, T. P.; Brunnbauer, M.; Stellacci, F.; Gang, O.; BNL; Massachusetts Inst. of Tech.; Univ. of Massachusetts; Harvard Univ.; Univ. Massachusetts

    2006-01-01

    The controlled self-assembly of thiol stabilized gold nanocrystals in a mediating solvent and confined within mesoporous alumina was probed in situ with small angle x-ray scattering. The evolution of the self-assembly process was controlled reversibly via regulated changes in the amount of solvent condensed from an undersaturated vapor. Analysis indicated that the nanoparticles self-assembled into cylindrical monolayers within the porous template. Nanoparticle nearest-neighbor separation within the monolayer increased and the ordering decreased with the controlled addition of solvent. The process was reversible with the removal of solvent. Isotropic clusters of nanoparticles were also observed to form temporarily during desorption of the liquid solvent and disappeared upon complete removal of liquid. Measurements of the absorption and desorption of the solvent showed strong hysteresis upon thermal cycling. In addition, the capillary filling transition for the solvent in the nanoparticle-doped pores was shifted to larger chemical potential, relative to the liquid/vapor coexistence, by a factor of 4 as compared to the expected value for the same system without nanoparticles.

  11. Alumina Inlay Failure in Cemented Polyethylene-backed Total Hip Arthroplasty

    OpenAIRE

    Iwakiri, Kentaro; Iwaki, Hiroyoshi; Minoda, Yukihide; Ohashi, Hirotsugu; Takaoka, Kunio

    2008-01-01

    Alumina-on-alumina bearings for THA have markedly improved in mechanical properties through advances in technology; however, alumina fracture is still a concern. We retrospectively reviewed 77 patients (82 hips) with cemented alumina-on-alumina THAs to identify factors relating to alumina failure. The mean age of the patients at surgery was 63 years. The prostheses had a cemented polyethylene-backed acetabular component with an alumina inlay and a 28-mm alumina head. Revision surgery was perf...

  12. Monitoring Transport Across Modified Nanoporous Alumina Membranes

    Directory of Open Access Journals (Sweden)

    Erich D. Steinle

    2007-11-01

    Full Text Available This paper describes the use of several characterization methods to examinealumina nanotubule membranes that have been modified with specific silanes. The functionof these silanes is to alter the transport properties through the membrane by changing thelocal environment inside the alumina nanotube. The presence of alkyl groups, either long(C18 or short and branched (isopropyl hydrocarbon chains, on these silanes significantlydecreases the rate of transport of permeant molecules through membranes containingalumina nanotubes as monitored via absorbance spectroscopy. The presence of an ionicsurfactant can alter the polarity of these modified nanotubes, which correlates to anincreased transport of ions. Fluorescent spectroscopy is also utilized to enhance thesensitivity of detecting these permeant molecules. Confirmation of the alkylsilaneattachment to the alumina membrane is achieved with traditional infrared spectroscopy,which can also examine the lifetime of the modified membrane. The physical parameters ofthese silane-modified porous alumina membranes are studied via scanning electronmicroscopy. The alumina nanotubes are not physically closed off or capped by the silanesthat are attached to the alumina surfaces.

  13. High contrast laser marking of alumina

    International Nuclear Information System (INIS)

    Highlights: • Laser marking of alumina using near infrared (NIR) lasers was experimentally analyzed. • Color change produced by NIR lasers is due to thermally induced oxygen vacancies. • Laser marking results obtained using NIR lasers and green laser are compared. • High contrast marks on alumina were achieved. - Abstract: Alumina serves as raw material for a broad range of advanced ceramic products. These elements should usually be identified by some characters or symbols printed directly on them. In this sense, laser marking is an efficient, reliable and widely implemented process in industry. However, laser marking of alumina still leads to poor results since the process is not able to produce a dark mark, yielding bad contrast. In this paper, we present an experimental study on the process of marking alumina by three different lasers working in two wavelengths: 1064 nm (Near-infrared) and 532 nm (visible, green radiation). A colorimetric analysis has been carried out in order to compare the resulting marks and its contrast. The most suitable laser operating conditions were also defined and are reported here. Moreover, the physical process of marking by NIR lasers is discussed in detail. Field Emission Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy and X-ray Photoelectron Spectroscopy were also employed to analyze the results. Finally, we propose an explanation for the differences of the coloration induced under different atmospheres and laser parameters. We concluded that the atmosphere is the key parameter, being the inert one the best choice to produce the darkest marks

  14. Superplastic properties of alumina-zirconia composites

    International Nuclear Information System (INIS)

    Superplastic deformation of two alumina-zirconia composites batches: the first with tetragonal ZrO2 stabilised with 3 mol.% Y2O3 and the second with ZrO2 stabilised with 2 mol.% Y2O3 (containing alumina volume fraction 10 - 86%) was studied. Grain sizes of two constituents were about 0.18-0.37 μm in the batch 1 and 0.36-0.14 μm in the batch 2. The composites were studied as a function of stress (20-130 MPa) and temperature (1451-1623 K) in compressive and bending tests. The strain rate was analysed in function of alumina volume fraction. It appeared that, the bigger than predicted by the rule of mixture strain rate decrease in function of alumina volume fraction is caused by improved creep resistance due to zirconium and yttrium ions doping of alumina grains. In zirconia grains modified interface-controlled Coble creep and simultaneously the intragranular dislocations motions contribute to the accommodation of grain boundary sliding (which is now thought to be main mechanism of superplastic behaviour). (author)

  15. Analysis of Capillary Rise in Asymmetric Branch-Like Capillary

    Science.gov (United States)

    Li, Caoxiong; Shen, Yinghao; Ge, Hongkui; Yang, Zhihui; Su, Shuai; Ren, Kai; Huang, Heyu

    2016-05-01

    Transport in porous media is common in nature, attracting many attentions for a long time. Tree-like network model is often used as a simplification for porous space, expressing the complexity of pore spaces instead of capillary bundle. To investigate spontaneous imbibition characteristics in this network, a dynamic asymmetric branch-like capillary model is used to represent basic network structure, using fractal method to represent tortuosity. This work investigates the influence of parameters on imbibition process in the branch-like capillary model. An analytical equation for the imbibition mass versus time is derived. Parameters from capillary structures to liquid properties are taken into account and analyzed based on the numerical solution of the equation. It is found that the imbibition process in asymmetric branch-like capillary model can be recognized by four sections and brunching tubes are positive for imbibition process. Concomitantly, meniscus arrest event is simulated and discussed. Moreover, the influence of parameters on imbibition process is discussed. These parameters can be classified as static and dynamic. Static parameters mainly change the capillary force, which are related to the ultimate imbibition mass or imbibition ability, while dynamic parameters mainly have influence on resistance of flowing fluid, which are related to the imbibition speed in the imbibition process.

  16. Position sensitive anodes for MCP read-out using induced charge measurement

    CERN Document Server

    Jagutzki, O; Mergel, V; Schmidt-Böcking, H; Spillmann, U; Worth, L B C

    2002-01-01

    We investigate the method of an indirect detection of a MCP charge avalanche projected onto a resistive layer (G. Battistoni, et al., Nucl. Instr. and Meth., 202 (1982) 459). If the sheet resistance is favourable one can detect the charge cloud by the capacitive coupling to an anode structure a few millimetres behind the layer. The anode structure can be, for example, a wedge-and-strip electrode pattern (M. Unverzagt, Diplomarbeit, Universitaet Frankfurt 1992, private communication) as it is used for directly collecting the electron avalanche from a MCP. Detection of the induced charge is beneficial in several respects. Firstly, image distortions produced by secondary electron mediated charge redistribution are eliminated. Secondly, the noise component due to quantized charge collection, commonly referred to as partition noise, is not present. In addition, the dielectric substrate can function both as an element of the vacuum enclosure and HV insulator, making the electrical connections easily accessible and ...

  17. Development of a rotordynamic analysis model for rotor shaft of SMART MCP

    International Nuclear Information System (INIS)

    A rotordynamic analysis model for rotor shaft assembly of SMART MCP was developed. The rotor shaft assembly consists of vertical spinning shaft, impeller, water lubricated bearing and canned motor. The analysis model includes journal bearing model, gap model between the motor stator and rotor, motor dynamic model, and impeller dynamic model. Reynolds' equation is applied to predict the stiffness and damping of the axially grooved journal bearings. Its solution is obtained by finite different method. Black's equation is used to calculate the stiffness, damping, and added mass for the small gap filled with water between the stator and rotor of motor. Dynamic parameters of impeller are calculated using Childs' equation which depicts the hydraulic imbalance forces. Electromagnetic force of canned motor is calculated using Iwata's model. The developed analysis model was applied to investigate the critical speeds, vibration mode shapes, and damped responses at bearings of the conceptually designed MCP rotor shaft

  18. Development of MCP-based photon diagnostics at the TESLA Test Facility at DESY

    International Nuclear Information System (INIS)

    A nondestructive radiation detector unit is under construction at the TESLA Test Facility at DESY providing monitoring of the radiation (pulse energy, transverse intensity distribution, and statistical properties). The concept of the detector design is based on experience obtained during operation of TTF FEL, Phase 1. Key element of the detector is a wide dynamic range micro-channel plate (MCP) which detects scattered radiation from a thin gold wire crossing photon beam. Operating wavelength range of the detector is from 6 to 100 nm. An important feature of the MCP-based detector is that it is capable to cover all dynamic range of the radiation intensity, from the level of spontaneous emission up to the saturation level of SASE FEL

  19. Evaluation of local MCP-1 and IL-12 nanocoatings for infection prevention in open fractures#

    OpenAIRE

    Li, Bingyun; Jiang, Bingbing; Dietz, Matthew J.; Smith, E. Suzanne; Clovis, Nina B.; Krishna Rao, K. Murali

    2010-01-01

    The increasing incidence of bacterial infection and the appearance of Staphylococcus aureus (S. aureus) strains that are resistant to commonly used antibiotics has made it important to develop non-antibiotic approaches for infection prevention. The aim of this study was to develop local monocyte chemoattractant protein-1 (MCP-1) and interleukin-12 p70 (IL-12 p70) therapies to prevent S. aureus infection by enhancing the recruitment and activation of macrophages, which are believed to play an ...

  20. State of art report for high temperature wear test of SMART MCP and CEDM bearing material

    International Nuclear Information System (INIS)

    Wear resistance properties of machine elements has been more critical in view of its significant effect on life extension, economics and material saving because it has been recognized that nearly 80 percent of damages of mechanical elements in the friction pairs are due to the material loss by wear. And wear properties have direct influence on the life of a machine in a great extend under extremely severe operating condition. Therefore highly improved wear properties of machine elements operating in such circumstances is heavily required. The purpose of this report is to survey current technology for high temperature wear test in order to establish the test plan for the life evaluation of SMART MCP and CEDM bearing materials. Friction and wear test will be done under high pressure (170 MPa) and high temperature (350 degree C) with water as lubricant to simulate the operating condition of the nuclear power reactor. Because pump type for MCP is selected as the caned motor pump which needs no mechanical sealing, the rotating shaft on which bearing is fully submerged by main coolant with high temperature. So MCP bearing operates without additional lubricant. CEDM is adopted as the ball-screw type with fine controllability. So the driving part is designed as the immersed-in type by main coolant. Therefore the anti-wear and reliability of driving parts are much consequent to guarantee the lifetime and the safety of the whole system. Tribometer adapted to high temperature and pressure circumstance is needed to execute bearing material testing. Test parameters are material, sliding speed, sliding distance and applied load. In order to identify the wear mechanism, optical microscope and surface roughness testers are required. The result of this report will provide an elementary data to develop bearing materials and to estimate bearing lifetime for the bearings of MCP and CEDM in SMART. (author)

  1. Lysophosphatidic Acid Stimulates MCP-1 Secretion from C2C12 Myoblast

    OpenAIRE

    Tamotsu Tsukahara; Hisao Haniu

    2012-01-01

    Chemokines are regulatory proteins that play an important role in muscle cell migration and proliferation. In this study, C2C12 cells treated with lysophosphatidic acid (LPA) showed an increase in endogenous monocyte chemotactic protein-1 (MCP-1) expression and secretion. LPA is a naturally occurring bioactive lysophospholipid with hormone- and growth-factor-like activities. LPA is produced by activated platelets, cytokine-stimulated leukocytes, and possibly by other cell types. However, the ...

  2. iPLA2β: front and center in human monocyte chemotaxis to MCP-1

    OpenAIRE

    Mishra, Ravi S.; Carnevale, Kevin A.; Cathcart, Martha K.

    2008-01-01

    Monocyte chemoattractant protein-1 (MCP-1) directs migration of blood monocytes to inflamed tissues. Despite the central role of chemotaxis in immune responses, the regulation of chemotaxis by signal transduction pathways and their in vivo significance remain to be thoroughly deciphered. In this study, we examined the intracellular location and functions of two recently identified regulators of chemotaxis, Ca2+-independent phospholipase (iPLA2β) and cytosolic phospholipase (cPLA2α), and subst...

  3. State of art report for high temperature wear test of SMART MCP and CEDM bearing material

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Hu; Lee, Jae Seon; Park, Jin Seok; Kim, Ji Ho; Kim, Jong In

    2000-03-01

    Wear resistance properties of machine elements has been more critical in view of its significant effect on life extension, economics and material saving because it has been recognized that nearly 80 percent of damages of mechanical elements in the friction pairs are due to the material loss by wear. And wear properties have direct influence on the life of a machine in a great extend under extremely severe operating condition. Therefore highly improved wear properties of machine elements operating in such circumstances is heavily required. The purpose of this report is to survey current technology for high temperature wear test in order to establish the test plan for the life evaluation of SMART MCP and CEDM bearing materials. Friction and wear test will be done under high pressure (170 MPa) and high temperature (350 degree C) with water as lubricant to simulate the operating condition of the nuclear power reactor. Because pump type for MCP is selected as the caned motor pump which needs no mechanical sealing, the rotating shaft on which bearing is fully submerged by main coolant with high temperature. So MCP bearing operates without additional lubricant. CEDM is adopted as the ball-screw type with fine controllability. So the driving part is designed as the immersed-in type by main coolant. Therefore the anti-wear and reliability of driving parts are much consequent to guarantee the lifetime and the safety of the whole system. Tribometer adapted to high temperature and pressure circumstance is needed to execute bearing material testing. Test parameters are material, sliding speed, sliding distance and applied load. In order to identify the wear mechanism, optical microscope and surface roughness testers are required. The result of this report will provide an elementary data to develop bearing materials and to estimate bearing lifetime for the bearings of MCP and CEDM in SMART. (author)

  4. Dielectric Performance of a High Purity HTCC Alumina at High Temperatures - a Comparison Study with Other Polycrystalline Alumina

    Science.gov (United States)

    Chen, Liangyu

    2014-01-01

    A very high purity (99.99+%) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this alumina material for co-firing processing. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96% polycrystalline alumina (96% Al2O3), where 96% alumina was used as the benchmark. A prototype packaging system based on regular 96% alumina with Au thickfilm metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500 C. In order to evaluate this new high purity HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96% alumina and a previously tested LTCC alumina from room temperature to 550 C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96% alumina and a selected LTCC alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  5. Challenges and Strategies in the Synthesis of Mesoporous Alumina Powders and Hierarchical Alumina Monoliths

    Directory of Open Access Journals (Sweden)

    Anne Galarneau

    2012-02-01

    Full Text Available A new rapid, very simple and one-step sol-gel strategy for the large-scale preparation of highly porous γ-Al2O3 is presented. The resulting mesoporous alumina materials feature high surface areas (400 m2 g−1, large pore volumes (0.8 mL g−1 and the ��-Al2O3 phase is obtained at low temperature (500 °C. The main advantages and drawbacks of different preparations of mesoporous alumina materials exhibiting high specific surface areas and large pore volumes such as surfactant-nanostructured alumina, sol-gel methods and hierarchically macro-/mesoporous alumina monoliths have been analyzed and compared. The most reproducible synthesis of mesoporous alumina are given. Evaporation-Induced Self-Assembly (EISA is the sole method to lead to nanostructured mesoporous alumina by direct templating, but it is a difficult method to scale-up. Alumina featuring macro- and mesoporosity in monolithic shape is a very promising material for in flow applications; an optimized synthesis is described.

  6. Mechanical properties of free standing porous anodic alumina films

    OpenAIRE

    Ignashev, E.; Shulgov, V.

    2012-01-01

    Free-standing films of anodic alumina obtained from the one-sided anodization of aluminum were studied. The flexural strength of free-standing porous anodic alumina films to the lateral bending, circular bending, and microhardness were studied.

  7. Qualidade de caqui 'Rama forte' após armazenamento refrigerado, influenciada pelos tratamentos 1-MCP e/ou CO2 Quality of 'Rama Forte' perssimon following cold torage influenced by 1-MCP and/or CO2treatments

    Directory of Open Access Journals (Sweden)

    João Peterson Pereira Gardin

    2012-12-01

    Full Text Available Avaliaram-se os efeitos dos tratamentos com CO2 e 1-MCP (1-metilciclopropeno sobre a adstringência (índice de tanino, firmeza da polpa e distúrbios da epiderme em caqui 'Rama Forte'. Frutos foram tratados com 1-MCP por 24 h, logo após a colheita e/ou com alto CO2 (70% por 24 ou 48 h, um dia após a colheita ou após o armazenamento refrigerado (AR. Os caquis foram armazenados sob atmosfera modificada a 0 ºC, por 45 dias, e a seguir mantidos a 23 ºC, por 9 dias. Frutos-controle (não tratados com 1-MCP nem com CO2 amoleceram em três dias e perderam aproximadamente 50% da adstringência em 6 dias após o AR. A exposição ao CO2 acelerou a redução da adstringência. Esse efeito do CO2 foi menor em frutos tratados com 1-MCP, especialmente quando o CO2 foi aplicado após o AR, por apenas 24 h. O tratamento com 1-MCP inibiu o amolecimento e a redução da adstringência, especialmente nos frutos não tratados com CO2. O amolecimento de frutos tratados com 1-MCP foi maior quando a exposição ao CO2 ocorreu antes do AR. A combinação dos tratamentos com 1-MCP e alto CO2 reduziu a incidência de podridões e manchas translúcidas, mas não alterou o desenvolvimento de pintas pretas ('estrias'. Os resultados indicam que é possível induzir perda da adstringência sem excessiva perda da firmeza da polpa de caquis 'Rama Forte' após o AR pela associação dos tratamentos com 1-MCP logo após a colheita e alto CO2 após o AR.This study evaluated the effects of CO2 and 1-MCP (1-methylcyclopropene treatments on astringency (tannin index, flesh firmness and skin disorders on 'Rama Forte' persimmon. Fruit were treated with 1-MCP for 24 h right after harvest and/or with high CO2 (70% CO2 balanced with air for 24 or 48 h, one day after harvest or after cold storage (CS. Fruit were stored in modified atmosphere for 45 days at 0ºC and then held at 23ºC for 9 days. Control fruit (untreated with neither 1-MCP nor CO2 softened in 3 days and lost about 50

  8. Surface Tension and Capillary Rise

    Science.gov (United States)

    Walton, Alan J.

    1972-01-01

    Discussion of the shortcomings of textbook explanations of surface tension, distinguishing between concepts of tension and capillary rise. The arguments require only a clear understanding of Newtonian mechanics, notably potential energy. (DF)

  9. Capillary Condensation in Confined Media

    CERN Document Server

    Charlaix, Elisabeth

    2009-01-01

    We review here the physics of capillary condensation of liquids in confined media, with a special regard to the application in nanotechnologies. The thermodynamics of capillary condensation and thin film adsorption are first exposed along with all the relevant notions. The focus is then shifted to the modelling of capillary forces, to their measurements techniques (including SFA, AFM and crack tips) and to their influence on AFM imaging techniques as well as on the static and dynamic friction properties of solids (including granular heaps and sliding nanocontacts). A great attention is spent in investigating the delicate role of the surface roughness and all the difficulties involved in the reduction of the probe size to nanometric dimensions. Another major consequence of capillary condensation in nanosystems is the activation of several chemical and corrosive processes that can significantly alter the surface properties, such as dissolution/redeposition of solid materials and stress-corrosion crack propagati...

  10. Capillary electrophoresis electrospray ionization mass spectrometry interface

    Science.gov (United States)

    Smith, Richard D.; Severs, Joanne C.

    1999-01-01

    The present invention is an interface between a capillary electrophoresis separation capillary end and an electrospray ionization mass spectrometry emitter capillary end, for transporting an anolyte sample from a capillary electrophoresis separation capillary to a electrospray ionization mass spectrometry emitter capillary. The interface of the present invention has: (a) a charge transfer fitting enclosing both of the capillary electrophoresis capillary end and the electrospray ionization mass spectrometry emitter capillary end; (b) a reservoir containing an electrolyte surrounding the charge transfer fitting; and (c) an electrode immersed into the electrolyte, the electrode closing a capillary electrophoresis circuit and providing charge transfer across the charge transfer fitting while avoiding substantial bulk fluid transfer across the charge transfer fitting. Advantages of the present invention have been demonstrated as effective in providing high sensitivity and efficient analyses.

  11. Dynamical Mechanical Properties for AD90 Alumina

    Institute of Scientific and Technical Information of China (English)

    REN Hui-lan; NING Jian-guo; LI Ping

    2007-01-01

    The dynamic response of polycrystalline alumina was investigated in the pressure range of 0 -13 GPa by planar impact experiments.Velocity interferometer system for any reflector(VISAR) was used to obtain free surface velocity profile and determine the Hugoniot elastic limit,and manganin gauges were employed to obtain the stress-time histories and determine Hugoniot curve.Both the free surface particle velocity profiles and Hugoniot curves indicate the dispersion of the "plastic" wave for alumina.With the measured stress histories,the complete histories of strain,particle velocity,specific volume and specific internal energy are gained by using path line principle of Lagrange analysis.The dynamic mechanical behaviors for alumina under impact loading are analyzed,such as nonlinear characteristic,strain rate dependence,dispersion and declination of shock wave in the material.

  12. Synthesis and characterization of alumina precursor and alumina to be used as nano composite; Sintese e caracterizacao de precursores de alumina e alumina para uso em nanocompositos

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, M.L.P., E-mail: malu@sorocaba.unesp.b [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sorocaba, SP (Brazil); Santos, H. Souza [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Santos, P. Souza [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica

    2009-07-01

    With the evolution of nanomaterials technology, mainly in the 90s, it was possible to observe produced composites with alumina matrix and nanomaterial as reinforcing materials. It results in a significant improvement of mechanical proprieties of these composites. Thenceforth the study of synthesis and characterization of nanostructured materials has attracted great scientific interest. In this perspective, the aim of this work is to present an experimental procedure to obtain nordstrandite (aluminum hydroxide) with nanometric dimensions. Nordstrandite synthesis, obtained by the reaction of slightly amalgamated aluminum foil with aqueous ethylene glycol, which allows the control of the size of crystal produced. This control could be confirmed by X-Ray Diffraction and Electron Microscopy. Thermal transformation study is also presented. This study allowed the identification of transition aluminas that have potential to produce nanometric aluminas. (author)

  13. Ethylene and 1-MCP regulate major volatile biosynthetic pathways in apple fruit.

    Science.gov (United States)

    Yang, Xiaotang; Song, Jun; Du, Lina; Forney, Charles; Campbell-Palmer, Leslie; Fillmore, Sherry; Wismer, Paul; Zhang, Zhaoqi

    2016-03-01

    The effects of ethylene and 1-methylcyclopropene (1-MCP) on apple fruit volatile biosynthesis and gene expression were investigated. Statistical analysis identified 17 genes that changed significantly in response to ethylene and 1-MCP treatments. Genes encoding branched-chain amino acid aminotransferase (BCAT), aromatic amino acid aminotransferase (ArAT) and amino acid decarboxylases (AADC) were up-regulated during ripening and further enhanced by ethylene treatment. Genes related to fatty acid synthesis and metabolism, including acyl-carrier-proteins (ACPs), malonyl-CoA:ACP transacylase (MCAT), acyl-ACP-desaturase (ACPD), lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), pyruvate decarboxylase (PDC2), β-oxidation, acyl-CoA synthetase (ACS), enoyl-CoA hydratase (ECHD), acyl-CoA dehydrogenase (ACAD), and alcohol acyltransferases (AATs) also increased during ripening and in response to ethylene treatment. Allene oxide synthase (AOS), alcohol dehydrogenase 1 (ADH1), 3-ketoacyl-CoA thiolase and branched-chain amino acid aminotransferase 2 (BCAT2) decreased in ethylene-treated fruit. Treatment with 1-MCP and ethylene generally produced opposite effects on related genes, which provides evidence that regulation of these genes is ethylene dependent. PMID:26471562

  14. Application of MCP-N (Lif: Mg, Cu, P TL detectors in monitoring environmental radiation

    Directory of Open Access Journals (Sweden)

    Olko Pavel

    2004-01-01

    Full Text Available Thermoluminescent MCP-N detectors based on LiF:Mg,Cu,P are by about 2 orders of magnitude more sensitive than TLD-100 detectors based on conventional LiF:Mg,Ti, which makes it possible to use them in short-term monitoring of ionizing radiation in the environment (e. g., over a two-week period, rather than over 3-12 months. We describe the properties of MCP-N detectors and methods of their application in environmental monitoring. The system was tested in short and long-term exposure periods at 100 sites around Krakow region. MCP-N detectors were then applied to measure variation of radiation dose rate at four selected villages in Serbia, where depleted uranium ammunition was deployed in 1999. Together with short-term thermoluminescent dosimetry, in situ measurements using proportional counters were per formed in order to assess the range of variation of natural radiation background in these villages. The mean terrestrial kerma dose rate in these villages was found to vary between 85 and 116 nGyh–1 and the average ambient dose equivalent rate H*(10 determined by thermoluminescent detectors and by proportional counter measurements was 160 nSvh–1. These values of natural radiation back ground dose rates can be applied as reference levels for field measurements around other sites where depleted uranium ammunition was deployed.

  15. 昂达N7AS 最便宜的MCP7A主板

    Institute of Scientific and Technical Information of China (English)

    刘宗宇

    2009-01-01

    NVIDIA的整合芯片组最大的优点就是具有优异的3D图形性能.曾今代号为C51、C61以及MCP68的三款AMD平台整合图形芯片组均获得了消费者的认可。而此后,NVIDIA又推出了针对Intel平台的MCP7A芯片组,同样备受关注。但是,由于苹果笔记本电脑大量采购该芯片组造成缺货,而且一线品牌的MCP7A主板价格又比较高,所以该芯片组主板的市场表现并不理想。最近,昂达推出了采用该芯片组的N7AS主板,售价仅为599元,创造了市场价格的新低。

  16. Forward Multiplicity TOF Spectra and Timing Resolution Simulations for FMD-MCP

    CERN Document Server

    Tulina, T; CERN. Geneva; Zabrodin, E

    1997-01-01

    We present here model simulation studies of two factors relevant to the high timing resolution expected from the FMD-MCP at ALICE: (i) the physical TOF spectra of charged particles in Pb-Pb collisions integrated over the whole FMD-MCP disk for central and for minimum bias events and (ii) the performance of the passive summator Abstract: at the output of FMD-MCP, creating an analogous sum of all input signals. Results show that the rise time of the integrated TOF spectrum signal is about or smaller than 100 ps for all disks. This confirms the proposed application of high timing resolution detector. The noiseless passive summation of fast signals coming through N input channels gives the improvement of the timing resolution compared to that of the individual channel by a factor of about àN. Thus both studies point to the feasibility of the proposed applications of a fast detector with high timing performance and of the passive summation idea.

  17. Blocking of grain reorientation in self-doped alumina materials

    International Nuclear Information System (INIS)

    Alumina nanoparticles 10-20 nm in diameter were nucleated on alumina particles, 150 nm average diameter, by a colloidal route followed by calcination. It is shown that after sintering, the final grain size is up to 20% smaller due to the addition of the alumina nanoparticles. Electron backscattered diffraction analysis shows that whereas a correlation in the relative crystalline orientations between neighbouring grains exists in the pure materials, the addition of alumina nanoparticles results in a random crystalline orientation.

  18. A Novel Processing Route for Ni-doped Alumina Composites

    Institute of Scientific and Technical Information of China (English)

    JING Mao-xiang; SHEN Xiang-qian; ZHOU Jian-xin; LI Dong-hong; LI Wang-xing

    2006-01-01

    Alumina-based composites containing 0-15wt% Ni metallic phase were produced by hot press-sintering Ni-coated alumina powders. The Ni-coated alumina powders were prepared by the aqueous heterogeneous precipitation of alumina micro-powders and nickel sulfate salt followed by reduction process. The microstructural features and dispersion of Ni phase in Ni-coated alumina powders and the subsequent alumina-Ni cermets were investigated using scanning electron microscope (SEM), X-ray diffractometer (XRD), and transmission electron microscope (TEM). The relative density of the hot press-sintered composites was measured with the Archimedes' method while the fracture strength and the fracture toughness were defined with the three-point bending method and the micro-indentation fracture method. In the formation of alumina-Ni cermets from sintered Ni-coated alumina powders, Ni phase to some extent limits the densification rate and stifles the coarsening and growing process of alumina grains. The Ni phase is found to be located at the interfaces and the triple-joint junctions of alumina grains which results into alteration of the fracture mode of alumina and its increased fracture strength and fracture toughness if compared with monolithic alumina.

  19. Tribological properties of nanoscale alumina-zirconia composites

    NARCIS (Netherlands)

    Kerkwijk, B.; Winnubst, A.J.A.; Verweij, H.; Mulder, E.J.; Metselaar, H.S.C.; Schipper, D.J.

    1999-01-01

    The tribological properties of zirconia (Y-TZP), alumina and their composites, alumina dispersed in zirconia (ADZ) and zirconia-toughened alumina (ZTA), were investigated. These ceramics are made by colloidal processing methods such that well-defined, homogeneous microstructures with submicron grain

  20. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  1. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Siloxane modified alumina... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  2. Pattern recognition of monocyte chemoattractant protein-1 (MCP-1) in whole blood samples using new platforms based on nanostructured materials

    Science.gov (United States)

    Stefan-van Staden, Raluca-Ioana; Gugoasa, Livia Alexandra; Biris, Alexandru Radu

    2015-09-01

    Four stochastic microsensors based on nanostructured materials (graphene, maltodextrin (MD), and diamond) integrated in miniaturized platforms were proposed. Monocyte chemoattractant protein-1 (MCP-1) is a pro-inflammatory cytokine whose main function is to regulate cell trafficking. It is correlated with the incidence of cardiovascular diseases and obesity, and was used as the model analyte in this study. The screening of whole blood samples for MCP-1 can be done for concentrations ranging from 10-12 to 10-8 g mL-1. The method was used for both qualitative and quantitative assessments of MCP-1 in whole blood samples. The lowest quantification limits for the assay of MCP-1 (1 pg mL-1) were reached when the microsensors based on protoporphyrin IX/Graphene-Au-3 and on MD/Graphene were employed in the platform design.

  3. Secretion of MCP-1 and other paracrine factors in a novel tumor-bone coculture model

    International Nuclear Information System (INIS)

    The bone-tumor microenvironment encompasses unique interactions between the normal cells of the bone and marrow cavity and the malignant cells from a primary or metastasized cancer. A multitude of paracrine factors within this microenvironment such as the growth factor, TGF-β, and the chemokine, MCP-1, are secreted by many of these cell types. These factors can act in concert to modulate normal and malignant cell proliferation, malignant cell migration and invasion and, often, mediate bone cancer pain. Although many valuable in vitro and in vivo models exist, identifying the relevant paracrine factors and deciphering their interactions is still a challenge. The aim of our study is to test an ex vivo coculture model that will allow monitoring of the expression, release and regulation of paracrine factors during interactions of an intact femur explant and tumor cells. Intact or marrow-depleted neonatal mouse femurs and select murine and human sarcoma or carcinoma cell lines were incubated singly or in coculture in specialized well plates. Viability of the bone and cells was determined by immunohistochemical stains, microscopy and marrow cytopreps. Secretion and mRNA expression of paracrine factors was quantitated by ELISA and real-time RT-PCR. Compartments of the bone were optimally viable for up to 48 h in culture and tumor cells for up to 4 days. Bone was the major contributor of TGF-β and MMP2 whereas both bone and sarcoma cells secreted the chemokine MCP-1 in cocultures. Synergistic interaction between the femur and sarcoma resulted in enhanced MCP-1 secretion and expression in cocultures and was dependent on the presence of the hematopoietic component of the bone as well as other bone cells. In contrast, coculturing with breast carcinoma cells resulted in reduction of TGF-β and MCP-1 secretion from the bone. These studies illustrate the feasibility of this model to examine paracrine interactions between intact bone and tumor cells. Further study of unique

  4. Effect of pharmacological intervention on MIP-1α, MIP-1β and MCP-1 expression in patients with psoriasis vulgaris

    Institute of Scientific and Technical Information of China (English)

    Yong-Jiang Dai; Yu-Yang Li; Hui-Ming Zeng; Xiong-An Liang; Zhi-Jie Xie; Zhi-Ang Zheng; Qin-Hui Pan; Yi-Xiong Xing

    2014-01-01

    Objective:To detect the expression level of macrophage inflammatory protein-1(MIP-1)α, MIP-1β and monocyte chemoattractant protein-1(MCP-1) in with psoriasis vulgaris and explore the role in the pathogenesis of psoriasis vulgaris.Methods:The level ofMIP-1α,MIP-1β andMCP-1 in peripheral blood from50 patients with psoriasis vulgaris and50 normal controls were measured by enzyme linked immunosorbent assay.The correlation with psoriasis area and severity index(PASI) was analyzed.The level ofMIP-1α,MIP-1β andMCP-1 was compared between psoriasis vulgaris patients at active stage and resting stage.And the change inMIP-1α, MIP-1β andMCP-1 before and after therapy was also observed.Results:The content ofMIP-1α, MIP-1β andMCP-1 in patients with psoriasis vulgaris was(1342.78±210.30),(175.28±28.18) and (266.86±32.75) ng/L, respectively, significantly higher than those in control group(P<0.05).The expression level ofMIP-1α,MIP-1β andMCP-1 in peripheral blood of patients with psoriasis vulgaris was positively correlated withPASI(P<0.01).After acitretin therapy, expression level ofMIP-1α,MIP-1β andMCP-1 in peripheral blood of patients with psoriasis vulgaris was significantly decreased.Conclusions:Chemokine factorMIP-1α,MIP-1β andMCP-1 may be involved in the pathogenesis of psoriasis vulgaris.

  5. Mutant MCP-1 Protein Delivery from Layer-by-Layer Coatings on Orthopaedic Implants to Modulate Inflammatory Response

    OpenAIRE

    Keeney, Michael; Waters, Heather; Barcay, Katie; Jiang, Xinyi; Yao, Zhenyu; Pajarinen, Jukka; Egashira, Kensuke; Goodman, Stuart; Yang, Fan

    2013-01-01

    Total joint replacement (TJR) is a common and effective surgical procedure for hip or knee joint reconstruction. However, the production of wear particles is inevitable for all TJRs, which activates macrophages and initiates an inflammatory cascade often resulting in bone loss, prosthetic loosening and eventual TJR failure. Macrophage Chemoattractant Protein-1 (MCP-1) is one of the most potent cytokines responsible for macrophage cell recruitment, and previous studies suggest that mutant MCP-...

  6. Ultrasound Color Doppler Image Segmentation and Feature Extraction in MCP and Wrist Region in Evaluation of Rheumatoid Arthritis.

    Science.gov (United States)

    Snekhalatha, U; Muthubhairavi, V; Anburajan, M; Gupta, Neelkanth

    2016-09-01

    The present study focuses on automatically to segment the blood flow pattern of color Doppler ultrasound in hand region of rheumatoid arthritis patients and to correlate the extracted the statistical features and color Doppler parameters with standard parameters. Thirty patients with rheumatoid arthritis (RA) and their total of 300 joints of both the hands, i.e., 240 MCP and 60 wrists were examined in this study. Ultrasound color Doppler of both the hands of all the patients was obtained. Automated segmentation of color Doppler image was performed using color enhancement scaling based segmentation algorithm. The region of interest is fixed in the MCP joints and wrist of the hand. Features were extracted from the defined ROI of the segmented output image. The color fraction was measured using Mimics software. The standard parameters such as HAQ score, DAS 28 score, and ESR was obtained for all the patients. The color fraction tends to be increased in wrist and MCP3 joints which indicate the increased blood flow pattern and color Doppler activity as part of inflammation in hand joints of RA. The ESR correlated significantly with the feature extracted parameters such as mean, standard deviation and entropy in MCP3, MCP4 joint and the wrist region. The developed automated color image segmentation algorithm provides a quantitative analysis for diagnosis and assessment of RA. The correlation study between the color Doppler parameters with the standard parameters provides moral significance in quantitative analysis of RA in MCP3 joint and the wrist region. PMID:27449351

  7. Study of the molybdenum retention in alumina; Estudio de la retencion de molibdeno en alumina

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, Maria V.; Mondino, Angel V.; Manzini, Alberto [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Centro Atomico Ezeiza. Radioquimica y Quimica de las Radiaciones

    2002-07-01

    The Argentine National Atomic Energy Commission routinely produces {sup 99} Mo by fission of highly enriched uranium contained in targets irradiated in RA-3 reactor. The current process begins with the dissolution of the irradiated target in a basic media, considering the possibility of changing the targets, it could be convenient to dissolve them in acid media. The use of alumina as a first separation step in acid dissolution processes is already known although it is necessary to determine both the type of alumina to be used and the separation conditions. The study of molybdenum retention in alumina was performed at laboratory scale, using Mo-99 as radiotracer. Different kinds of alumina were tried, varying charge solution acidity. Influence of uranium concentration in the loading solution on molybdenum retention was also studied. (author)

  8. Study on alumina-alumina brazing for application in vacuum chambers of proton synchrotron

    International Nuclear Information System (INIS)

    The paper describes an experimental study to standardize vacuum brazing process to obtain satisfactory high purity alumina brazed joints for application in rapid cycle proton synchrotron machine. Two different brazing routes, adopted for making alumina-alumina brazed joints, included (i) multi-step Mo-Mn metallization and brazing with BVAg-8 alloy and (ii) advanced single-step active brazing with CuSil-ABA alloy. Brazed alumina specimens, prepared by both the routes, yielded ultra high vacuum compatible, helium leak tight and bakeable joints. Active-brazed specimens exhibited satisfactory strength values in tensile and four-point bend tests. Metallized-brazed specimens, although exhibited relatively lower tensile strength than the targeted value, displayed satisfactory flexural strength in four-point bend test. The results of the study demonstrated that active brazing is the simple and cost effective alternative to conventional metallization route for producing satisfactory brazed joints for application in rapid cycle proton synchrotron machine. (author)

  9. Selective metallization of alumina by laser

    NARCIS (Netherlands)

    Shrivastva, P.B.; Boose, C.A.; Kolster, B.H.; Harteveld, C.; Meinders, B.

    1991-01-01

    Nickel has been selectively deposited on an alumina substrate without any pretreatment from a flow of a nickel acetate solution using the focused beam of an excimer laser. Nickel spots as well as nickel lines were drawn and subsequently plated with an electroless Ni-B coating. Excellent adhesion of

  10. Adsorption of Nitrogen on Organized Mesoporous Alumina

    Czech Academy of Sciences Publication Activity Database

    Čejka, Jiří; Veselá, Lenka; Rathouský, Jiří; Zukal, Arnošt

    Amsterdam : Elsevier, 2002 - (Sayari, A.; Jaroniec, M.), s. 429-436 - ( Studies in Surface Science and Catalysis.. 141). [International Symposium on Nanoporous Materials /3./. Ottawa (CA), 12.06.2002-15.06.2002] R&D Projects: GA MŠk ME 404 Institutional research plan: CEZ:AV0Z4040901 Keywords : alumina * nitrogen * adsorption Subject RIV: CF - Physical ; Theoretical Chemistry

  11. Method of making nanocrystalline alpha alumina

    Science.gov (United States)

    Siegel, Richard W.; Hahn, Horst; Eastman, Jeffrey A.

    1992-01-01

    Method of making selected phases of nanocrystalline ceramic materials. Various methods of controlling the production of nanocrystalline alpha alumina and titanium oxygen phases are described. Control of the gas atmosphere and use of particular oxidation treatments give rise to the ability to control the particular phases provided in the aluminum/oxygen and titanium/oxygen system.

  12. Mechanical properties of zirconia-toughened alumina

    International Nuclear Information System (INIS)

    Bend samples of four compositions of zirconia-toughened alumina were heat treated at 10000C for 100 and 500 H and tested for strength and fracture toughness at room temperature. These results are compared with as-received properties, as well as stress rupture and stepped-temperature stress rupture data

  13. Dielectric Performance of High Purity HTCC Alumina at High Temperatures - A Comparison Study with Other Polycrystalline Alumina

    Science.gov (United States)

    Chen, Liang-Yu

    2012-01-01

    A very high purity (99.99+) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this co-fired material. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96 polycrystalline alumina (96 Al2O3), where 96 alumina was used as the benchmark. A prototype packaging system based on regular 96 alumina with Au thick-film metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500C. In order to evaluate this new HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96 alumina and a LTCC alumina from room temperature to 550C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96 alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  14. MECHANICAL BEHAVIOUR OF ALUMINA-ZIRCONIA COMPOSITE BY SLURRY METHOD

    Directory of Open Access Journals (Sweden)

    JYOTI PRAKASH

    2011-02-01

    Full Text Available Alumina has got some excellent properties like chemical inertness, thermal and mechanical strength against hazardous environment. Alumina is a good ceramic material which is being used for structuralapplications. To enhance the toughness and strength of the body some Zirconia is also used with it. The use of Zirconia in alumina is known as toughening of alumina. One difficulty arises, when alumina and alumina toughened composite are sintered , because the low sinterability of Alumina-Zirconia forced the compact to give very low density body. To overcome this problem alumina and alumina composites are made from slurry method which gives nearly theoretical density. The combined effect of alumina and Zirconia on the phase transformation and microstructure development of heat-treated Alumina-Zirconia composites has been studied. Slurry is prepared by adding water, dispersant, binder and anti-foaming agent. In the present study, Sintering schedule is optimized and kept constant for all samples. After sintering, mechanical behaviour of the composite has been studied.

  15. Laser-based capillary polarimeter.

    Science.gov (United States)

    Swinney, K; Hankins, J; Bornhop, D J

    1999-01-01

    A laser-based capillary polarimeter has been configured to allow for the detection of optically active molecules in capillary tubes with a characteristic inner diameter of 250 microm and a 39-nL (10(-9)) sample volume. The simple optical configuration consists of a HeNe laser, polarizing optic, fused-silica capillary, and charge-coupled device (CCD) camera in communication with a laser beam analyzer. The capillary scale polarimeter is based on the interaction between a polarized laser beam and a capillary tube, which results in a 360 degree fan of scattered light. This array of scattered light contains a set of interference fringe, which respond in a reproducible manner to changes in solute optical activity. The polarimetric utility of the instrument will be demonstrated by the analysis of two optically active solutes, R-mandelic acid and D-glucose, in addition to the nonoptically active control, glycerol. The polarimetric response of the system is quantifiable with detection limits facilitating 1.7 x 10(-3) M or 68 x 10(-12) nmol (7 psi 10(-9) g) sensitivity. PMID:11315158

  16. Effect of thermal residual stresses on the strength for both alumina/Ni/alumina and alumina/Ni/nickel alloy bimaterials

    OpenAIRE

    Hattali, Lamine; Stéphane, Valette; Ropital, Francois; Mesrati, Nadir; Tréheux, Daniel

    2009-01-01

    This paper describes some technical limitations encountered in joining ceramics-ceramics or ceramics-metals, and how, to some extent, they have been practically overcome. The effect of the residual stresses on the strength of joints fabricated between alumina-alumina or alumina and the nickel base alloy HAYNES 214TM using a solid-state bonding technique with Ni interlayer was studied. Finite element analyses (FEA) for the elastic-plastic and elastic-plastic-creep behavior have also been used ...

  17. Degradation of alumina and zirconia toughened alumina (ZTA) hip prostheses tested under microseparation conditions in a shock device

    CERN Document Server

    Uribe, Juliana; Gremillard, Laurent; Reynard, Bruno

    2013-01-01

    This paper considers the degradation of alumina and zirconia toughened alumina vs. alumina for hip implants. The materials are as assumed to be load bearing surfaces subjected to shocks in wet conditions. The load is a peak of force; 9 kN was applied over 15 ms at 2 Hz for 800,000 cycles. The volumetric wear and roughness are lower for ZTA than for alumina. The long ZTA ageing did not seem to have a direct influence on the roughness. The ageing increased the wear volumes of ZTA and it was found to have a higher wear resistance compared to alumina.

  18. Characterization of Glasses in One Type of Alumina Rich Fly Ash by Chemical Digestion Methods: Implications for Alumina Extraction

    OpenAIRE

    Lijun Zhao; Hanshuang Xiao; Baodong Wang; Qi Sun

    2016-01-01

    In recent years, one type of alumina rich fly ash (ARFA) with about 50 wt% of alumina has been extensively investigated for alumina extraction in China. Due to the silica in ARFA, alumina extraction would have to generate a huge amount of solid waste. There is a growing interest in the glasses in ARFA, because they are composed mainly of silica and could be removed prior to alumina extraction. In this work, the glasses in ARFA have been investigated by chemical methods, that is, acid and base...

  19. Impacts on oil recovery from capillary pressure and capillary heterogeneities

    Energy Technology Data Exchange (ETDEWEB)

    Bognoe, Thomas

    2008-07-01

    The main conclusions drawn from this thesis are; 7 scientific papers are published on a broad variety of subjects, and describes in detail the experiments and research treated in this thesis. Scientific research has been performed, investigating the subjects of capillary pressure and capillary heterogeneities from different angles. This thesis discusses the findings in this study and aims to illustrate the benefits of the results obtained for further development of other experiments, and/or even the industrial benefits in field development. The methods for wettability alteration have developed throughout the work. From producing heterogeneous wettability alterations, the methods have improved to giving both radial and lateral uniform wettability alterations, which also remains unaltered throughout the duration of the experimental work. The alteration of wettability is dependent on initial water saturation, flow rate, aging time and crude oil composition. Capillary pressure and relative permeability curves have been measured for core plugs at different wettabilities using conventional centrifuge methods. The trends observed are mostly consistent with theory. The production mechanisms of strongly and moderately water wet chalk has been investigated. At strongly water wet conditions in fractured chalk; the flow is governed by capillary forces, showing strong impact from the fractures. At moderately water wet conditions, the impact of the fractures are absent, and a dispersed water front is observed during the displacement. The oil recovery is about the same, at the two wettabilities. Fracture crossing mechanisms at the same wettability conditions have been mapped. And the observations are consistent with those of the water floods. During strongly water wet displacement, the fracture crossing is occurring once the inlet core has reached endpoint of spontaneous imbibition. At moderately water wet conditions the fracture crossing is less abrupt, and creation of wetting

  20. Fabrication and Enhanced Thermoelectric Properties of Alumina Nanoparticle-Dispersed Bi0.5Sb1.5Te3 Matrix Composites

    Directory of Open Access Journals (Sweden)

    Kyung Tae Kim

    2013-01-01

    Full Text Available Alumina nanoparticle-dispersed bismuth-antimony-tellurium matrix (Al2O3/BST composite powders were fabricated by using ball milling process of alumina nanoparticle about 10 nm and p-type bismuth telluride nanopowders prepared from the mechanochemical process (MCP. The fabricated Al2O3/BST composite powders were a few hundreds of nanometer in size, with a clear Bi0.5Sb1.5Te3 phase. The composite powders were consolidated into p-type bulk composite by spark plasma sintering process. High-resolution TEM images reveal that alumina nanoparticles were dispersed among the grain boundary or in the matrix grain. The sintered 0.3 vol.% Al2O3/BST composite exhibited significantly improved power factor and reduced thermal conductivity in the temperature ranging from 293 to 473 K compared to those of pure BST. From these results, the highly increased ZT value of 1.5 was obtained from 0.3 vol.% Al2O3/BST composite at 323 K.

  1. Non-Aqueous Capillary Electrophoresis

    Science.gov (United States)

    Szumski, Michał; Buszewski, Bogusław

    Non-aqueous capillary electrophoresis and capillary electrochromatography are special variants of these techniques. Here, organic solvents or their mixtures with or without dissolved electrolytes are used as separation buffer or mobile phase, respectively. The most important features of non-aqueous systems are: better solubility of more hydrophobic ionic substances (many natural products) than in water, much less current and Joule heating allows for using highly concentrated buffers and/or larger capillary internal diameters, polar interactions are enhanced in organic solvents which is often highly advantageous in chiral separation systems. This chapter presents most frequently used solvents, their properties, as well as shows pH* scale which is often used in non-aqueous systems.

  2. Graphene coated with alumina and its utilization as a thermal conductivity enhancer for alumina sphere/thermoplastic polyurethane composite

    International Nuclear Information System (INIS)

    Graphene was oxidized with H2O2 to introduce additional anchoring sites for effective alumina coating on graphene by the sol–gel method. The X-ray photoelectron spectroscopy studies showed that the oxygen-containing groups such as hydroxyl group useful for coating were introduced by the oxidation. The transmission electron microscopy images and thermogravimetric analysis data demonstrated that the additional anchoring sites enhanced the efficiency of the alumina coating. A small amount of alumina-coated graphene synergistically improved the thermal conductivity of the alumina sphere/thermoplastic polyurethane (TPU) composite without any increase in the electrical conductivity, because the electrical conductivity of graphene effectively decreased by the alumina coating. Moreover, the synergistic effect of a small amount of graphene was enhanced by the alumina coating, and the stiffening of the alumina sphere/TPU composite due to the added graphene was alleviated by the alumina coating. - Highlights: • Oxidation of graphene with H2O2 introduced anchoring sites for alumina coating. • The anchoring sites improved the efficiency of alumina coating on graphene. • The alumina-coated graphene synergistically enhanced the thermal conductivity

  3. Rheological Properties of Aqueous Nanometric Alumina Suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Chuanping Li

    2004-12-19

    Colloidal processing is an effective and reliable approach in the fabrication of the advanced ceramic products. Successful colloidal processing of fine ceramic powders requires accurate control of the rheological properties. The accurate control relies on the understanding the influences of various colloidal parameters on the rheological properties. Almost all research done on the rheology paid less attention to the interactions of particle and solvent. However, the interactions of the particles are usually built up through the media in which the particles are suspended. Therefore, interactions of the particle with the media, the adsorbed layers on the particle surface, and chemical and physical properties of media themselves must influence the rheology of the suspension, especially for the dense suspensions containing nanosized particles. Relatively little research work has been reported in this area. This thesis addresses the rheological properties of nanometric alumina aqueous suspensions, and paying more attention to the interactions between particle and solvent, which in turn influence the particle-particle interactions. Dense nanometric alumina aqueous suspensions with low viscosity were achieved by environmentally-benign fructose additives. The rheology of nanometric alumina aqueous suspensions and its variation with the particle volume fraction and concentration of fructose were explored by rheometry. The adsorptions of solute (fructose) and solvent (water) on the nanometric alumina particle surfaces were measured and analyzed by TG/DSC, TOC, and NMR techniques. The mobility of water molecules in the suspensions and its variation with particle volume fractions and fructose additive were determined by the {sup 17}O NMR relaxation method. The interactions between the nanometric alumina particles in water and fructose solutions were investigated by AFM. The results indicated that a large number of water layers were physically bound on the particles

  4. 挑战690G——NVIDIA MCP68系列芯片组

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    NVIDIA7是AMD平台整台芯片组市场上最重要的供应商。凭借性能出色,GeForce6100+nForce41D/430(即我们常说的051)芯片组以及后来将南北桥合二为一的MCP61V/SIP(即我们常说的C61)芯片组一直是大家在AMD整合平台上的首选。

  5. Atraso do amadurecimento de banana 'Maçã' pelo 1-MCP, aplicado previamente à refrigeração Ripening delay of 'Apple' banana submitted to 1-MCP, prevoiously applied to refrigeration

    Directory of Open Access Journals (Sweden)

    Gustavo Costa Almeida

    2006-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de diferentes períodos de exposição da banana 'Maçã' a 50 ppb de 1-MCP (0; 3; 6; 9; 12 e 24 horas sobre sua vida pós-colheita e qualidade. Após exposição ao 1-MCP, os frutos verde-maturos foram armazenados por 30 dias em câmaras com temperatura de 13ºC ± 0,5 e umidade relativa de 95%. Em seguida, as bananas foram armazenadas à temperatura de 20ºC ± 1, até amarelecimento completo da casca. A exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 9 horas, retardou em 7 dias o seu amadurecimento, em comparação a frutos não expostos ao 1-MCP, após 30 dias de armazenamento refrigerado (13ºC, sem prejuízos à sua aparência e composição química. A exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 3 e 6 horas, não estendeu sua vida pós-colheita, tampouco alterou sua composição química. Embora a exposição de banana 'Maçã' a 50 ppb de 1-MCP, por 12 e 24 horas, tenha retardado o seu amadurecimento, promoveu alterações indesejáveis na casca do fruto. Logo, a aplicação de 50 ppb de 1-MCP, por 9 horas, antes da refrigeração, constitui-se numa alternativa viável para prolongar o período de comercialização da banana.The aim of this work was to evaluate 'Apple' banana different periods exposure effect to 50 ppb of 1-MCP (0, 3, 6, 9 and 24 hours on its postharvest life and quality. Mature-green fruits were stored for 30 days in chambers at 13ºC + 0,5 and relative humidity 95%, after exposure to 1-MCP. Then, the bananas were stored at 20ºC + 1 until peel complete yellowing. 'Apple' banana to 50 ppb of 1-MCP exposure during 9 hours delayed in seven days the fruit ripening, comparing to fruit control, after 30 days of cool storage (13ºC, without changing its appearance and chemical composition. The exposure of 'Apple' banana to 50 ppb of 1-MCP for 3 and 6 hours did not extend its postharvest life; neither changed its chemical composition. Although the exposure of

  6. The TORCH PMT: a close packing, multi-anode, long life MCP-PMT for Cherenkov applications

    International Nuclear Information System (INIS)

    Photek (U.K.) and the TORCH collaboration are undertaking a three year development program to produce a novel square MCP-PMT for single photon detection. The TORCH detector aims to provide particle identification in the 2–10 GeV/c momentum range, using a Time-of-Flight method based on Cherenkov light. It is a stand-alone R and D project with possible application in LHCb, and has been proposed for the LHCb Upgrade. The Microchannel Plate (MCP) detector will provide a single photon timing accuracy of 40 ps, and its development will include the following properties: (i) Long lifetime up to at least 5 C/cm2; (ii) Multi-anode output with a spatial resolution of 6 mm and 0.4 mm respectively in the horizontal and vertical directions, incorporating a novel charge-sharing technique; (iii) Close packing on two opposing sides with an active area fill factor of 88% in the horizontal direction. Results from simulations modelling the MCP detector performance factoring in the pulse height variation from the detector, NINO threshold levels and potential charge sharing techniques that enhance the position resolution beyond the physical pitch of the pixel layout will be discussed. Also, a novel method of coupling the MCP-PMT output pads using Anisotropic Conductive Film (ACF) will be described. This minimises parasitic input capacitance by allowing very close proximity between the frontend electronics and the MCP detector

  7. Tenderization effect of cold-adapted collagenolytic protease MCP-01 on beef meat at low temperature and its mechanism.

    Science.gov (United States)

    Zhao, Guo-Yan; Zhou, Ming-Yang; Zhao, Hui-Lin; Chen, Xiu-Lan; Xie, Bin-Bin; Zhang, Xi-Ying; He, Hai-Lun; Zhou, Bai-Cheng; Zhang, Yu-Zhong

    2012-10-15

    The enzymes currently used to increase meat tenderness are all mesophilic or thermophilic proteases. This study provides insight into the tenderization effect and the mechanism of a cold-adapted collagenolytic enzyme MCP-01 on beef meat at low temperatures. MCP-01 (10 U of caseinolytic activity) reduced the meat shear force by 23% and increased the relative myofibrillar fragmentation index of the meat by 91.7% at 4 °C, and it also kept the fresh colour and moisture of the meat. Compared to the commercially used tenderizers papain and bromelain, MCP-01 showed a unique tenderization mechanism. MCP-01 had a strong selectivity for degrading collagen at 4 °C, showed a distinct digestion pattern on the myofibrillar proteins, and had a different disruption pattern on the muscle fibres under scanning electron micrograph. These results suggest that the cold-adapted collagenolytic protease MCP-01 may be promising for use as a meat tenderizer at low and moderate temperatures. PMID:23442615

  8. Lack of association of recipient MCP-1 gene promoter polymorphism with acute graft rejection after orthotopic liver transplantation.

    Science.gov (United States)

    Franco-López, E; González-Escribano, M F; Aguilera, I; Pascasio, J M; Pareja, F; Bernardos, A; Núñez-Roldán, A

    2005-04-01

    Acute graft rejection after orthotopic liver transplantation (OLT) is associated with leukocyte infiltration of the graft. Monocyte chemoattractant protein-1 (MCP-1) is a beta-chemokine involved in the attraction and accumulation of mononuclear granulocytes toward sites of inflammation. A biallelic polymorphism (G/A) at position -2518 of the MCP-1 gene has been described. Cells obtained from individuals with the GG or AG genotypes have been found to produce more MCP-1 than those obtained from individuals with the AA genotype. The goal of this study was to assess the possible association between this polymorphism and susceptibility to acute graft rejection after OLT. One hundred fifty Caucasian liver transplant recipients from the South of Spain underwent genotyping using a polymerase chain reaction (PCR) amplification followed by restriction fragment length polymorphism (RFLP). No significant differences were observed when patients with versus without acute rejection episodes were compared for the distribution of -2518 MCP-1 genotypes. The present study supports the lack of involvement of polymorphism at position -2518 (A/G) of the MCP-1 gene on the susceptibility to acute allograft rejection among OLT recipients. PMID:15866653

  9. Mcp3 is a novel mitochondrial outer membrane protein that follows a unique IMP-dependent biogenesis pathway.

    Science.gov (United States)

    Sinzel, Monika; Tan, Tao; Wendling, Philipp; Kalbacher, Hubert; Özbalci, Cagakan; Chelius, Xenia; Westermann, Benedikt; Brügger, Britta; Rapaport, Doron; Dimmer, Kai Stefan

    2016-07-01

    Mitochondria are separated from the remainder of the eukaryotic cell by the mitochondrial outer membrane (MOM). The MOM plays an important role in different transport processes like lipid trafficking and protein import. In yeast, the ER-mitochondria encounter structure (ERMES) has a central, but poorly defined role in both activities. To understand the functions of the ERMES, we searched for suppressors of the deficiency of one of its components, Mdm10, and identified a novel mitochondrial protein that we named Mdm10 complementing protein 3 (Mcp3). Mcp3 partially rescues a variety of ERMES-related phenotypes. We further demonstrate that Mcp3 is an integral protein of the MOM that follows a unique import pathway. It is recognized initially by the import receptor Tom70 and then crosses the MOM via the translocase of the outer membrane. Mcp3 is next relayed to the TIM23 translocase at the inner membrane, gets processed by the inner membrane peptidase (IMP) and finally integrates into the MOM. Hence, Mcp3 follows a novel biogenesis route where a MOM protein is processed by a peptidase of the inner membrane. PMID:27226123

  10. High-pressure phases of alumina

    Science.gov (United States)

    Lyle, Matthew; Pickard, Chris; Needs, Richard

    2014-03-01

    Alumina (Al2O3) has been widely used as a pressure standard in static diamond anvil cell experiments and is a major chemical component of the Earth. So a detailed knowledge of its high-pressure stability is of great importance in both materials science and deep Earth science. A phase transition is known to occur at roughly 80-100 GPa between corundum and the Rh2O3 (II) structure. A second phase transition to the CaIrO3 structure occurs at even higher pressures. Here we present a computational structure search to reveal three additional structures which are competitive at these pressures but hitherto unknown to be stable in high-pressure alumina.

  11. Li + ion diffusion in nanoscale alumina coatings

    Science.gov (United States)

    Johannes, Michelle; Bernstein, Noam

    Nanoscale coatings of alumina are used to stabilize surfaces for a variety of technologies. Diffusion of ions through these coatings is of primary importance: in some cases, diffusion is unwanted (e.g. corrosion) and in others (e.g. electrode materials), it is necessary. In this work DFT and AIMD calculations are used to investigate Li+ ion diffusion through a nano-layer of alumina, examining the phase (alpha, gamma, and amorphous), ion concentration, and electron count dependence. We look at the role of the surface itself in promoting diffusion. One of our main findings is that as the number of ions or charge increases, the diffusivity rises. We show how our data can explain electrochemical data from coated LiCoO2 cathodes and may point toward better and more efficient coatings for stabilizing electrodes.

  12. Slip casting alumina with Na-CMC

    Energy Technology Data Exchange (ETDEWEB)

    Ruys, A.J.; Sorrell, C.C. [Univ. of New South Wales, Sydney, New South Wales (Australia)

    1996-11-01

    Many forming methods are in common use for engineering ceramics. Of these, slip casting is an ideal forming method because of its low cost, simplicity and flexibility, potential for uniform particle packing and suitability to the production of articles of intricate shape. Slip casting nonclay materials, such as alumina, requires the use of both a deflocculant and a binder. There are many commercially available deflocculants and binders that can be tested in alumina casting slips. However, determination of a suitable deflocculant/binder combination and quantification of the optimal additions of the deflocculant/binder pair can be time consuming. Certain deflocculants are capable of acting as binders. One such additive is sodium carboxymethylcellulose (Na-cmc), a cellulose ether. Na-cmc is a powerful binder. It is a member of the carbohydrate binder group--the binder group with the strongest binding power. It is capable of acting as a deflocculant in glazes and nonclay casting slips.

  13. Microstructural evolution of alumina-zirconia nanocomposites

    International Nuclear Information System (INIS)

    Ceramic materials have limited use due to their brittleness. The inclusion of nanosized particles in a ceramic matrix, which are called nanocomposites, and ceramic processing control by controlling the grain size and densification can aid in obtaining ceramic products of greater strength and toughness. Studies showed that the zirconia nano inclusions in the matrix of alumina favors an increase in mechanical properties by inhibiting the grain growth of the matrix and not by the mechanism of the transformation toughening phase of zirconia. In this work, the microstructural evolution of alumina nanocomposites containing 15% by volume of nanometric zirconia was studied. From the results it was possible to understand the sintering process of these nanocomposites. (author)

  14. Activation of consolidation processes of alumina ceramics

    Science.gov (United States)

    Matrenin, S. V.; Zenin, B. S.; Tayukin, R. V.

    2016-02-01

    The methods for activating sintering ceramics based on Al2O3 by mechanical activation in the planetary mill, by adding in the mixture of nanopowders (NP) Al, Al2O3, and submicron powder TiO2, and by applying the technology of spark plasma sintering (SPS) are developed. It has been shown that adding the nanopowder up to 20 wt. % Al2O3 in a coarse powder α-Al2O3 activates the sintering process resulting in increased density and hardness of the sintered alumina ceramics. Substantial effect of increasing density of alumina ceramics due to adding the submicron powder TiO2 in the compound of initial powder mixtures has been established.

  15. Mesoscale Modelling of the Response of Aluminas

    International Nuclear Information System (INIS)

    The response of polycrystalline alumina to shock is not well addressed. There are several operating mechanisms that only hypothesized which results in models which are empirical. A similar state of affairs in reactive flow modelling led to the development of mesoscale representations of the flow to illuminate operating mechanisms. In this spirit, a similar effort is undergone for a polycrystalline alumina. Simulations are conducted to observe operating mechanisms at the micron scale. A method is then developed to extend the simulations to meet response at the continuum level where measurements are made. The approach is validated by comparison with continuum experiments. The method and results are presented, and some of the operating mechanisms are illuminated by the observed response

  16. MCP-1, ICAM-1 and VCAM-1 are present in early aneurysmal dilatation in experimental rats

    International Nuclear Information System (INIS)

    Recent studies have suggested that inflammation actively participates in ascending aortic aneurysm formation. The aim of the present study was to evaluate the expression changes of adhesion molecules and MMPs in an experimental model of ascending aortic aneurysm induced by ascending aorta banding in Wistar rats. Twelve rats developed aortic dilation after ascending aorta banding treatment, while nine normal animals underwent surgery without banding were used as controls. Light microscope and scanning electron microscope showed that the wall of the ascending aorta became disorganized as well as infiltration by inflammatory cells in aneurysmal rats. By using immunohistochemical techniques, a significant increase in the immunostaining of MCP-1 was observed in the aneurysmal wall as compared to the normal aortic wall. Under similar experimental conditions, we also found that the immunostaining of ICAM-1 and VCAM-1 was markedly increased in the aneurysmal wall. In addition, gelatin zymo graphic analysis showed that the expression and activities of MMP-2 and MMP-9 were remarkably enhanced in the ascending aorta of ascending aortic aneurysmal rats as compared to normal rats. These results demonstrate that MCP-1, ICAM-1 and VCAM-1 are involved in the pathogenesis of ascending aortic aneurysm and an increase in the immunostaining and activity of MMP-2 and MMP-9 may promote the progression of ascending aortic aneurysm. (authors)

  17. MCP-PMT studies at the High-B test facility at Jefferson Lab

    International Nuclear Information System (INIS)

    Here we present preliminary results for the gain performance of commercially available 3-μm and 6-μm pore-size single-anode microchannel-plate photomultipliers (MCP PMTs) in magnetic fields up to 5 T and for various orientations of the sensor relative to the field direction. The measurements were performed at Thomas Jefferson National Accelerator Facility in Newport News, VA. Our results show that smaller-pore-size PMTs have better gain performance in magnetic fields. At various angles, the shape of the gain dependence on the strength of the magnetic field strongly depends on the type of the sensor. Also, for each sensor, the azimuthal dependence is strongly correlated with the polar angle. Overall, the sensors exhibit a reasonable performance up to 2 T, although that upper limit depends on the sensor, the applied high voltage, and the orientation of the sensor relative to the field. To optimize the operational and design parameters of MCP PMTs for performance in high magnetic fields, further measurements and simulation studies will be pursued. Our studies are part of an R and D for development of a Detector of Internally Reflected Cherenkov Light for the central detector of a future U.S. Electron Ion Collider

  18. MCP-PMT studies at the High-B test facility at Jefferson Lab

    Science.gov (United States)

    Ilieva, Y.; Allison, L.; Cao, T.; Kalicy, G.; Nadel-Turonski, P.; Park, K.; Schwarz, C.; Schwiening, J.; Zorn, C.

    2016-03-01

    Here we present preliminary results for the gain performance of commercially available 3-μm and 6-μm pore-size single-anode microchannel-plate photomultipliers (MCP PMTs) in magnetic fields up to 5 T and for various orientations of the sensor relative to the field direction. The measurements were performed at Thomas Jefferson National Accelerator Facility in Newport News, VA. Our results show that smaller-pore-size PMTs have better gain performance in magnetic fields. At various angles, the shape of the gain dependence on the strength of the magnetic field strongly depends on the type of the sensor. Also, for each sensor, the azimuthal dependence is strongly correlated with the polar angle. Overall, the sensors exhibit a reasonable performance up to 2 T, although that upper limit depends on the sensor, the applied high voltage, and the orientation of the sensor relative to the field. To optimize the operational and design parameters of MCP PMTs for performance in high magnetic fields, further measurements and simulation studies will be pursued. Our studies are part of an R&D for development of a Detector of Internally Reflected Cherenkov Light for the central detector of a future U.S. Electron Ion Collider.

  19. Fast front-end L0 trigger electronics for ALICE FMD-MCP tests and performance

    CERN Document Server

    Efimov, L G; Kasatkan, V; Klempt, W; Kuts, V; Lenti, V; Platanov, V; Rudge, A; Stolyarov, O I; Tsimbal, F A; Valiev, F F; Villalobos Baillie, O; Vinogradov, L I; Zhigunov, O

    1997-01-01

    We present design details and new measurements of the performance of fast electronics for the Forward Multiplicity Detector for ALICE. These detectors based on sector type Microchannel Plates (MCP) forming several disks gave the very first trigger decision in the experiment (L0). Fast passive summators integrated with the detectors are used for linear summation of up to eight isochronous signal channels from MCP pads belonging to one sector. Two types of microelectronics design thin film summators were produced. We present test results for these summators, working in the frequency range up to 1 Ghz. New low noise preamplifiers have been built to work with these summators. The new design shows a good performance with the usable frequency range extended up to 1 Ghz. An upgrade of the functional scheme for the L0 ALICE pre-trigger design is also presented.Abstract:List of figures Figure 1: ALICE L0 Trigger Front-End Electronics Functional Scheme. Figure 2: UHF design for a fast passive summator based on direct...

  20. Capillary thinning of polymeric filaments

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Szabo, Peter

    1999-01-01

    The capillary thinning of filaments of a Newtonian polybutene fluid and a viscoelastic polyisobutylene solution are analyzed experimentally and by means of numerical simulation. The experimental procedure is as follows. Initially, a liquid sample is placed between two cylindrical plates. Then, th...

  1. Capillary thinning of polymeric filaments

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Szabo, Peter; Hassager, Ole

    The capillary thinning of a polymeric filament is analysed experimentally as well as by means of numerical simulation. The experimental procedure is as follows. Initially a liquid sample is kept between two cylindrical plates. Then the bottom plate is lowered under gravity to yield a given strain...

  2. Capillary Rise in a Wedge

    Science.gov (United States)

    Piva, M.

    2009-01-01

    In introductory-level physics courses, the concept of surface tension is often illustrated using the example of capillary rise in thin tubes. In this paper the author describes experiments conducted using a planar geometry created with two small plates forming a thin wedge. The distribution of the fluid entering the wedge can be studied as a…

  3. Aplicação de 1-MCP em caqui 'quioto' armazenado sob refrigeração e atmosfera controlada Effect of 1-MCP applied at different times during cold and Ca storage

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2003-04-01

    Full Text Available O objetivo deste trabalho foi de avaliar o efeito do 1-MCP aplicado em diferentes épocas durante o armazenamento refrigerado (AR e em atmosfera controlada (AC sobre a qualidade do caqui cv. Quioto. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições de 30 frutos, e os tratamentos foram os seguintes: armazenamento refrigerado (AR; armazenamento refrigerado(AR + 1-MCP (1000ppb no início do armazenamento; armazenamento refrigerado(AR +1-MCP (1000ppb no final do armazenamento; armazenamento em atmosfera controlada (AC com 1kPa de O2 e AC 5kPa de CO2 e AC com 1kPa de O2 e 5kPa de CO2 + 1-MCP no fim do armazenamento, após 2 meses de armazenamento a -0,5ºC mais 5 dias de exposição dos frutos a 10ºC e 3 dias a 20ºC. No armazenamento refrigerado, o 1-MCP, aplicado tanto no início do armazenamento como no final, proporcionou maior firmeza de polpa. Para os parâmetros: sólidos solúveis totais, podridão e escurecimento da película, não houve diferença estatística entre os tratamentos. Conclui-se que a aplicação de 1-MCP, tanto no início como no final do armazenamento mantém elevada a firmeza de polpa.The objective of this work was to evaluate the effect of 1-MCP applied at different period during the cold storage (CS and in controlled atmosphere (CA on the quality of 'Quioto'. Persimmon. The experimental design was completely randomized with four replications of 30 fruits and the tested treatments were: cold storage (CS, cold storage + 1-MCP (1000ppb in the beginning of the storage, cold storage + 1-MCP (1000ppb in the end of the storage period; storage in controlled atmosphere (CA with 1kPa of O2 and 5kPa of CO2 and 1kPa of O2 and 5kPa of CO2 + 1-MCP in the end of the storage, after 2 months of storage at -0.5ºC, plus 5 days at 10ºC and 3 days at 20ºC. In the cooled storage, the 1-MCP, applied as in the beginning of the storage as in the end of the storage, provided greater pulp firmness

  4. Detection and clinical significance of MCP-1 in gingival crevicular fluid from patients with chronic periodontitis%慢性牙周炎患者龈沟液中MCP-1的检测及临床意义

    Institute of Scientific and Technical Information of China (English)

    张遵; 孙青; 王晓丽

    2011-01-01

    目的:检测慢性牙周炎患者龈沟液中单核细胞趋化蛋白-1(MCP-1)的浓度,并探讨其与牙周临床指标及碱性磷酸酶分泌的关系.方法:采用常规滤纸条法收集慢性牙周炎患者基础治疗前(T1)、基础治疗后(T2)及正常对照组(C)各位点的龈沟液样本,用ELISA法检测各样本中MCP-1及碱性磷酸酶的浓度.采用SPSS11.0软件包对数据进行t检验和直线相关分析.结果:3组受检者中,慢性牙周炎患者龈沟液中MCP-1平均浓度显著高于正常对照组(P<0.01),基础牙周治疗可使牙周炎患者龈沟液中MCP-1含量显著下降(P<0.01),治疗前后MCP-1的浓度变化与菌斑指数、探诊深度、牙龈指数、临床附着丧失以及碱性磷酸酶的分泌均呈正相关.结论:MCP-1作为一个重要的炎性趋化因子参与了慢性牙周炎的发生、发展过程,龈沟液MCP-1可作为牙周病防治及疗效评估的潜在靶分子.%PURPOSE: To evaluate the concentration of monocyte chemoattractant protein-1 (MCP-1) in the gingival crevicular fluid from patients with chronic periodontitis and its correlation with clinic periodontal parameters as well as alkaline phosphates secretions.METHODS: Gingival crevicular fluid (GCF) was collected with standardized filter strips from healthy control sites as well as periodontitis sites from chronic periodontitis patients before and after initial therapy,and the levels of MCP-1 and alkaline phosphatase were detected by ELISA.The data was analyzed with SPSS 11.0 software package.RESULTS: Concentration of MCP-1 in GCF was significantly higher in chronic periodontitis patients,and decreased significantly after initial therapy, the variation of MCP-1 correlated positively with clinical parameters like plaque index (PLI), probing depth (PD), gingival index (GI), clinic attachment lost (CAL) as well as alkaline phosphatase secretion.CONCLUSIONS: As an inflammatory chemotatic factor, MCP-1 in GCF may play an important role in occurrence

  5. Selective inhibition of the MCP-1-CCR2 ligand-receptor axis decreases systemic trafficking of macrophages in the presence of UHMWPE particles

    OpenAIRE

    Gibon, Emmanuel; Ma, Ting; Ren, Pei-Gen; Fritton, Kate; Biswal, Sandip; Yao, Zhenyu; Smith, Lane; Goodman, Stuart B.

    2011-01-01

    The biological mechanisms leading to periprosthetic osteolysis involve both chemokines and the monocyte/macrophage cell lineage. Whether MCP-1 plays a major role in macrophage recruitment in the presence of wear particles is unknown. We tested two hypotheses: (1) that exogenous local delivery of MCP-1 induces systematic macrophage recruitment and (2) that blockade of the MCP-1 ligand-receptor axis decreases macrophage recruitment and osteolysis in the presence of UHMWPE particles. Six groups ...

  6. Phototransferred thermoluminescence and exoemission in alpha alumina

    Energy Technology Data Exchange (ETDEWEB)

    Iacconi, P.; Lapraz, D.; Alessandri-Fraccaro, M.F.; Addi, D. (Univ. de Nice-Sophia Antipolis (France). Lab. d' Emission Electronique et de Luminescence)

    1990-01-01

    {alpha}-Al{sub 2}O{sub 3}, irradiated by ionising radiation and submitted to UV illumination, presents a phototransfer phenomenon that is characterised by thermoluminescence (TL) and by thermostimulated exoelectronic emission (TSEE). The TL and the TSEE glow curves of {alpha}-alumina from -196 to 700{sup 0}C are compared, to parallel one phototransfer observation with another and to draw various conclusions concerning the stability of the traps involved in dosimetric applications. (author).

  7. Selective metallization of alumina by laser

    OpenAIRE

    Shrivastva, P.B.; Boose, C.A.; Kolster, B.H.; Harteveld, C; Meinders, B.

    1991-01-01

    Nickel has been selectively deposited on an alumina substrate without any pretreatment from a flow of a nickel acetate solution using the focused beam of an excimer laser. Nickel spots as well as nickel lines were drawn and subsequently plated with an electroless Ni-B coating. Excellent adhesion of the metallized layers was achieved, since with laser irradiation, both etching and deposition took place simultaneously.

  8. Tribological behaviour of anodised alumina nanohoneycombs

    OpenAIRE

    Wang, Shuo; 王硕

    2012-01-01

    Anodic alumina nanohoneycombs (AAO) have been widely used because of its convenient fabrication and controllable pores’ geometry. A lot of investigations have been conducted to study its physical and chemical properties. However, the mechanical properties, especially tribological properties, of such a popular nanomaterial still remain almost unknown. In this project, a series of scratch experiments were conducted on AAO films fabricated by a two-step anodisation method. The testing system...

  9. Experimental investigation of the radiation shielding of a MCP detector in the radiation environment near Europa

    Science.gov (United States)

    Tulej, Marek; Wurz, Peter; Meyer, Stefan; Lasi, Davide; Lüthi, Matthias; Galli, André; Piazza, Daniele; Desorgher, Laurent; Hajdas, Wojciech; Reggiani, Davide; Karlsson, Stefan; Kalla, Leif

    2016-04-01

    The Neutral Ion Mass spectrometer (NIM) is one of the six instruments in the Particle Environmental Package (PEP) designed for the JUICE mission of ESA to the Jupiter system. NIM will conduct detailed measurements of chemical composition of Jovian moon exospheres and is equipped with a sensitive MCP ion detector. To maintain high sensitivity of the NIM instrument, background signals arising from the presence of a large background of penetrating radiation (mostly high-energy electrons and protons) in Jupiter's magnetosphere have to be minimised. We investigate the performance of a layered-Z radiation shield, an Al-Ta-Al sandwich, as a potential shielding against high-energy electrons. The experimental investigations were performed at the PiM1 beam line of the High Intensity Proton Accelerator Facilities located at the Paul Scherrer Institute (PSI), Villigen, Switzerland. The facility delivers a particle beam containing e,  and  with an adjustable momentum ranging from 17.5 to 345 MeV/c. The measurements of the induced radiation background generated during the interaction of primary particles with Al-Ta-Al sandwich were conducted by beam diagnostic methods and a MCP detector. Diagnostic methods provided for the characterisation of the beam parameters (beam geometry, flux and intensity) and identification of individual particles in the primary beam and in the flux of secondary particles. The MCP detector measurements provided information on the effects of radiation and the results of these measurements define the performance of the shielding material in reducing the background arising from penetrating radiation. In parallel, we performed modelling studies using GEANT 4 and GRASS methods to identify products of the interaction and predict their fluxes and particle rates at the MCP detector. Combination of the experiment and modelling studies yields detailed characterisation of the radiation effects produced by the interaction of the incident e- in the

  10. Novel calcium hexaluminate/spinel-alumina composites with graded microstructures and mechanical properties

    Science.gov (United States)

    Yi, Shuai; Huang, Zhaohui; Huang, Juntong; Fang, Minghao; Liu, Yan'gai; Zhang, Shaowei

    2014-03-01

    Calcium hexaluminate (CA6) was incorporated into the matrix of magnesio aluminate spinel-alumina (MA-A) via infiltration of a porous preform fabricated from α-Al2O3 and MgO powders with a saturated calcium acetate solution and subsequent firing, forming CA6/(MA-A) functionally composites with graded fracture toughness. Actually, the porous preform was partially and perpendicularly immersed (1/4 of its length) in the solution. Owing to the capillary action, the calcium acetate solution was absorbed into the porous preform, and the different absorption distance led to the graded solution concentration in the height direction of the porous preform. The in-situ formation of CA6 conferred graded microstructures, as well as improved mechanical properties on the resultant composites. The CA6 content decreased gradually along the solution absorption direction, i.e., from one end [CA6/(MA-A) region] immersed in solution to the other end [MA-A region], reducing evidently the formation of layered structure along the direction, while increasing gradually the formation of spherical alumina particles. The CA6/(MA-A) region had a better toughness that could prevent the crack propagation and improve the spalling resistance. Meanwhile, the MA-A region could provide structural support, because of the higher Vickers hardness and density.

  11. Separation of tungsten and rhenium on alumina

    Directory of Open Access Journals (Sweden)

    MILOVAN SM. STOILJKOVIC

    2004-09-01

    Full Text Available The conditions for the efficient separation of tungsten(VI and rhenium (VII on alumina were established. The distribution coefficients Kd for tungstate and perrhenate anions, as well as the separation factors a (a = KdWO42-/Kd ReO4- were determined using hydrochloric or nitric acid as the aqueous media. A solution of sodium chloride in the pH range 2–6 was also examined. Under all the tested experimental conditions, alumina is a much better adsorbent for tungsten than for rhenium. The obtained results indicated that the best separation of these two elements is achieved when 0.01– 0.1 mol dm-3 HCl or 1.0 mol dm-3 HNO3 are used as the aqueous media. If NaCl is used as the aqueous phase, the best separation is achieved with 0.20 mol dm-3 NaCl, pH 4–6. Under these experimental conditions, the breakthrough and saturation capacities of alumina for tungsten at pH 4 are 17 and 26 mg W/g Al2O3, respectively. With increasing pH, these values decrease. Thus, at pH 6 they are only 4 and 13 mg W/g Al2O3, respectively.

  12. MCP-1 upregulates amylin expression in murine pancreatic β cells through ERK/JNK-AP1 and NF-κB related signaling pathways independent of CCR2.

    Directory of Open Access Journals (Sweden)

    Kun Cai

    Full Text Available BACKGROUND: Amylin is the most abundant component of islet amyloid implicated in the development of type 2 diabetes. Plasma amylin levels are elevated in individuals with obesity and insulin resistance. Monocyte chemoattractant protein-1 (MCP-1, CCL2 is involved in insulin resistance of obesity and type 2 diabetes. We investigated the effect of MCP-1 on amylin expression and the underlying mechanisms with murine pancreatic β-cell line MIN6 and pancreatic islets. METHODOLOGY/PRINCIPAL FINDINGS: We found that MCP-1 induced amylin expression at transcriptional level and increased proamylin and intermediate forms of amylin at protein level in MIN6 cells and islets. However, MCP-1 had no effect on the expressions of proinsulin 1 and 2, as well as prohormone convertase (PC 1/3 and PC2, suggesting that MCP-1 specifically induces amylin expression in β-cells. Mechanistic studies showed that although there is no detectable CCR2 mRNA in MIN6 cells and islets, pretreatment of MIN6 cells with pertussis toxin inhibited MCP-1 induced amylin expression, suggesting that alternative Gi-coupled receptor(s mediates the inductive effect of MCP-1. MCP-1 rapidly induced ERK1/2 and JNK phosphorylation. Inhibitors for MEK1/2 (PD98059, JNK (SP600125 or AP1 (curcumin significantly inhibited MCP-1-induced amylin mRNA expression. MCP-1 failed to induce amylin expression in pancreatic islets isolated from Fos knockout mice. EMSA showed that JNK and ERK1/2 were involved in MCP-1-induced AP1 activation. These results suggest that MCP-1 induces murine amylin expression through AP1 activation mediated by ERK1/2 or JNK. Further studies showed that treatment of MIN6 cells with NF-κB inhibitor or overexpression of IκBα dominant-negative construct in MIN6 cells significantly inhibited MCP-1-induced amylin expression, suggesting that NF-κB related signaling also participates in MCP-1-induced murine amylin expression. CONCLUSIONS/SIGNIFICANCE: MCP-1 induces amylin expression

  13. MCP-1-Induced Histamine Release from Mast Cells Is Associated with Development of Interstitial Cystitis/Bladder Pain Syndrome in Rat Models

    Directory of Open Access Journals (Sweden)

    Jianwei Lv

    2012-01-01

    Full Text Available Objective. Interstitial cystitis/bladder pain syndrome (IC/BPS is characterized by overexpression of monocyte chemoattractant protein-1 (MCP-1 in bladder tissues and induction of mast cell (MC degranulation. This study was undertaken to explore the mechanism of action of MCP-1 in the development of IC/BPS. Methods. A rat model of IC/BPS was developed by perfusing bladders of nine SPF- grade female Sprague-Dawley rats with protamine sulfate and lipopolysaccharide (PS+LPS. MCP-1 and histamine levels in bladder tissue and urine were detected by immunohistochemistry and ELISA. MC degranulation was measured by immunofluorescence techniques and chemokine (C-C motif receptor 2 (CCR2 was assayed by flow cytometry. Results. Increased MCP-1 expression in bladder tissue and elevated MCP-1 and histamine levels were observed in the urine of LS+LPS-treated rats. This was accompanied by the expression of CCR2 on MC surfaces, suggesting MCP-1 may induce MC degranulation through CCR2. Exposure to LPS stimulated MCP-1 expression in bladder epithelial cells, and exposure to MCP-1 induced histamine release from MCs. Conclusions. MCP-1 upregulation in IC/BPS is one of possible contributing factors inducing histamine release from MCs. CCR2 is involved in the process of mast cell degranulation in bladder tissues. These changes may contribute to the development of symptoms of IC/BPS.

  14. MCP-1 Upregulates Amylin Expression in Murine Pancreatic β Cells through ERK/JNK-AP1 and NF-κB Related Signaling Pathways Independent of CCR2

    Science.gov (United States)

    Cai, Kun; Qi, Dongfei; Hou, Xinwei; Wang, Oumei; Chen, Juan; Deng, Bo; Qian, Lihua; Liu, Xiaolong; Le, Yingying

    2011-01-01

    Background Amylin is the most abundant component of islet amyloid implicated in the development of type 2 diabetes. Plasma amylin levels are elevated in individuals with obesity and insulin resistance. Monocyte chemoattractant protein-1 (MCP-1, CCL2) is involved in insulin resistance of obesity and type 2 diabetes. We investigated the effect of MCP-1 on amylin expression and the underlying mechanisms with murine pancreatic β-cell line MIN6 and pancreatic islets. Methodology/Principal Findings We found that MCP-1 induced amylin expression at transcriptional level and increased proamylin and intermediate forms of amylin at protein level in MIN6 cells and islets. However, MCP-1 had no effect on the expressions of proinsulin 1 and 2, as well as prohormone convertase (PC) 1/3 and PC2, suggesting that MCP-1 specifically induces amylin expression in β-cells. Mechanistic studies showed that although there is no detectable CCR2 mRNA in MIN6 cells and islets, pretreatment of MIN6 cells with pertussis toxin inhibited MCP-1 induced amylin expression, suggesting that alternative Gi-coupled receptor(s) mediates the inductive effect of MCP-1. MCP-1 rapidly induced ERK1/2 and JNK phosphorylation. Inhibitors for MEK1/2 (PD98059), JNK (SP600125) or AP1 (curcumin) significantly inhibited MCP-1-induced amylin mRNA expression. MCP-1 failed to induce amylin expression in pancreatic islets isolated from Fos knockout mice. EMSA showed that JNK and ERK1/2 were involved in MCP-1-induced AP1 activation. These results suggest that MCP-1 induces murine amylin expression through AP1 activation mediated by ERK1/2 or JNK. Further studies showed that treatment of MIN6 cells with NF-κB inhibitor or overexpression of IκBα dominant-negative construct in MIN6 cells significantly inhibited MCP-1-induced amylin expression, suggesting that NF-κB related signaling also participates in MCP-1-induced murine amylin expression. Conclusions/Significance MCP-1 induces amylin expression through ERK1/2/JNK

  15. Synthesis and characterization of single-crystalline alumina nanowires

    Institute of Scientific and Technical Information of China (English)

    ZHAO Qing; XU Xiang-yu; ZHANG Hong-zhou; CHEN Yao-feng; XU Jun; YU Da-peng

    2005-01-01

    Alumina nanowires were synthesized on large-area silicon substrate via simple thermal evaporation method of heating a mixture of aluminum and alumina powders without using any catalyst or template. The phase structure and the surface morphology of the as-grown sample were analyzed by X-ray diffractometry(XRD) and scanning electron microscopy (SEM), respectively. The chemical composition and the microstructure of the as-grown alumina nanowires were characterized using transmission electron microscope(TEM). The nanowires are usually straight and the single crystalline has average diameter of 40 nm and length of 3 - 5 μm. The growth direction is along the [002] direction. Well aligned alumina nanowire arrays were observed on the surface of many large particles. The catalyst-free growth of the alumina nanowires was explained under the framework of a vapor-solid(VS)growth mechanism. This as-synthesized alumina nanowires could find potential applications in the fabrication of nanodevices.

  16. Effect of the Cooling System and 1-MCP on the Incidence of Superficial Scald in ‘Granny Smith’ Apples Efecto del Sistema de Enfriamiento y 1-MCP sobre la Incidencia de Escaldado Superficial en Manzanas ‘Granny Smith’

    OpenAIRE

    Claudia Moggia; Omar Hernández; Marcia Pereira; Lobos, Gustavo A.; José Antonio Yuri

    2009-01-01

    A study was carried out to determine the effects of two cooling systems and the application of 1-methylcyclopropene (1-MCP, SmartFreshTM) on the incidence of superficial scald in apples (Malus domestica Borkh.) cv. Granny Smith. Fruit were collected from a commercial orchard (Colbún, Maule Region, Chile) during 2004-2005 season. A completely randomized design was used in a 2 x 2 factorial arrangement, using cooling systems (normal and step-wise cooling) and application of 1-MCP (0 and 625 nL ...

  17. Free-standing alumina nanobottles and nanotubes pre-integrated into nanoporous alumina membranes

    International Nuclear Information System (INIS)

    A novel interfacial structure consisting of long (up to 5 μm), thin (about 300 nm), highly-ordered, free-standing, highly-reproducible aluminum oxide nanobottles and long tubular nanocapsules attached to a rigid, thin (less than 1 μm) nanoporous anodic alumina membrane is fabricated by simple, fast, catalyst-free, environmentally friendly voltage-pulse anodization. A growth mechanism is proposed based on the formation of straight channels in alumina membrane by anodization, followed by neck formation due to a sophisticated voltage control during the process. This process can be used for the fabrication of alumina nanocontainers with highly controllable geometrical size and volume, vitally important for various applications such as material and energy storage, targeted drug and diagnostic agent delivery, controlled drug and active agent release, gene and biomolecule reservoirs, micro-biologically protected platforms, nano-bioreactors, tissue engineering and hydrogen storage. (paper)

  18. Atmospheric Moisture Content Effects on Ionic Liquid Wettability of Alumina

    OpenAIRE

    Brittle, S.; Samuel, A; W. B. Zimmerman

    2014-01-01

    The contact angles or wettability of 7 Ionic Liquids, on an alumina substrate, have been measured under two different storage conditions. The first using a small amount of moisture content, the second with no moisture content. The contact angle of Ionic Liquid droplets on an alumina substrate were measured using an Attension Theta instrument with automated software. The results show that a small amount of moisture improves the wettability of the Ionic Liquid – alumina system and therefore sub...

  19. Corrosion of Refractory Alumina-Graphite and Alumina-Graphite-Zirconia in Slag Containing Titania

    Institute of Scientific and Technical Information of China (English)

    XU Yuan; LIU Qing-cai; BAI Chen-guang; CHEN Deng-fu; Joseph W Newkirk

    2004-01-01

    The corrosion of refractory alumina-graphite and alumina-graphite-zirconia in the slag containing titania was studied by immersion tests (quasi-static and dynamic tests). Combining direct observation with microscopic investigations, a mechanism for corrosion was proposed based on the oxidation of graphite and the dissolution of refractory components. During the corrosion process, there are some special phenomena and laws that can be explained by the relation between the corrosion rate and the TiO2 mass percent, the rotational refractory velocity and the morphology of the deteriorated layer.

  20. Challenges and Strategies in the Synthesis of Mesoporous Alumina Powders and Hierarchical Alumina Monoliths

    OpenAIRE

    Anne Galarneau; Alexander Sachse; Sarah Hartmann

    2012-01-01

    A new rapid, very simple and one-step sol-gel strategy for the large-scale preparation of highly porous γ-Al2O3 is presented. The resulting mesoporous alumina materials feature high surface areas (400 m2 g−1), large pore volumes (0.8 mL g−1) and the ��-Al2O3 phase is obtained at low temperature (500 °C). The main advantages and drawbacks of different preparations of mesoporous alumina materials exhibiting high specific surface areas and large pore volumes such as surfactant-nanostructured alu...

  1. Rheology of Alumina-Based Graphite-Containing Castables

    Institute of Scientific and Technical Information of China (English)

    YE Fangbao; M. Rigaud; LIU Xinhong; ZHONG Xiangchong

    2005-01-01

    In this work, the rheological behavior of ultra-low cement alumina-based castables with addition of flake graphite and extruded graphite pellets has been investigated by using IBB rheometer. Emphasis has been laid on the influence of the type and amount of carbon addition on rheological properties of the alumina-based castables and the results are compared with corresponding alumina castable samples without any carbon addition. It is found that alumina-based castables with extruded graphite pellets have good rheological behavior and flowability with lower water demand ( < 6. 3% )and no segregation during the shearing of castable.

  2. Modelling the initial stage of porous alumina growth during anodization

    Science.gov (United States)

    Aryslanova, E. M.; Alfimov, A. V.; Chivilikhin, S. A.

    2013-05-01

    Artificially on the surface of aluminum there may be build a thick layer of Al2O3, which has a porous structure. In this paper we present a model of growth of porous alumina in the initial stage of anodizing, identifying dependencies anodizing parameters on the rate of growth of the film and the distance between the pores and as a result of the created model equations were found for changes in the disturbance of alumina for the initial stage of anodizing aluminum oxide porous border aluminum-alumina and alumina-electrolyte, with the influence of surface diffusion of aluminum oxide.

  3. Tribological and stability investigations of alkylphosphonic acids on alumina surface

    International Nuclear Information System (INIS)

    Alumina substrates are commonly used for various micro-/nanoelectromechanical systems (MEMS/NEMS). For efficient and lifetime longevity of these devices, lubricant films of self-assembled monolayers (SAMs) with nanometer thickness are increasingly being employed. In the present paper, we report preparation, tribological and stability investigations of alkylphosphonic acids on the alumina surface. The alkylphosphonic acids were prepared on the alumina surface using the liquid phase deposition method. The effectiveness of modification of the alumina surface by alkylphosphonic acids was investigated using water contact angle measurements, secondary ion mass spectrometry, X-ray photoelectron and infrared spectroscopy. Frictional behavior in milinewton load range was studied by microtribometry. It is shown that surface modification of the alumina surface by alkylphosphonic acids reduces the coefficient of friction values compared to the unmodified alumina. In comparison to the non-modified alumina surface, all tested alkylphosphonic acids cause a decrease in the friction coefficients in friction tests for counterparts made from different materials, such as steel, zirconia and silicon nitride. It is also found that the alumina surface modified by alkylphosphonic acids with longer chain has a higher degree of hydrophobicity and lower coefficient of friction. The best frictional properties are obtained for the system consisting of the alumina surface modified by n-octadecylphosphonic acid and silicon nitride counterpart. Stability tests in different environmental conditions: laboratory, acidic and alkaline solutions were also monitored.

  4. Monocytes infiltrate the pancreas via the MCP-1/CCR2 pathway and differentiate into stellate cells.

    Directory of Open Access Journals (Sweden)

    Kazuko Ino

    Full Text Available Recent studies have shown that monocytes possess pluripotent plasticity. We previously reported that monocytes could differentiate into hepatic stellate cells. Although stellate cells are also present in the pancreas, their origin remains unclear. An accumulation of enhanced green fluorescent protein (EGFP(+CD45(- cells was observed in the pancreases and livers of chimeric mice, which were transplanted with a single hematopoietic stem cell isolated from EGFP-transgenic mice and treated with carbon tetrachloride (CCl4. Because the vast majority of EGFP(+CD45(- cells in the pancreas expressed stellate cell-associated antigens such as vimentin, desmin, glial fibrillary acidic protein, procollagen-I, and α-smooth muscle actin, they were characterized as pancreatic stellate cells (PaSCs. EGFP(+ PaSCs were also observed in CCl4-treated mice adoptively transferred with monocytes but not with other cell lineages isolated from EGFP-transgenic mice. The expression of monocyte chemoattractant protein-1 (MCP-1 and angiotensin II (Ang II increased in the pancreas of CCl4-treated mice and their respective receptors, C-C chemokine receptor 2 (CCR2 and Ang II type 1 receptor (AT1R, were expressed on Ly6C(high monocytes isolated from EGFP-transgenic mice. We examined the effect of an AT1R antagonist, irbesartan, which is also a CCR2 antagonist, on the migration of monocytes into the pancreas. Monocytes migrated toward MCP-1 but not Ang II in vitro. Irbesartan inhibited not only their in vitro chemotaxis but also in vivo migration of adoptively transferred monocytes from peripheral blood into the pancreas. Irbesartan treatment significantly reduced the numbers of EGFP(+F4/80(+CCR2(+ monocytic cells and EGFP(+ PaSCs in the pancreas of CCl4-treated chimeric mice receiving EGFP(+ bone marrow cells. A specific CCR2 antagonist RS504393 inhibited the occurrence of EGFP(+ PaSCs in injured mice. We propose that CCR2(+ monocytes migrate into the pancreas possibly via the

  5. Degradation of alumina and zirconia toughened alumina (ZTA) hip prostheses tested under microseparation conditions in a shock device

    OpenAIRE

    Uribe, Juliana; Geringer, Jean; Gremillard, Laurent; Reynard, Bruno

    2011-01-01

    This paper considers the degradation of alumina and zirconia toughened alumina vs. alumina for hip implants. The materials are as assumed to be load bearing surfaces subjected to shocks in wet conditions. The load is a peak of force; 9 kN was applied over 15 ms at 2 Hz for 800,000 cycles. The volumetric wear and roughness are lower for ZTA than for alumina. The long ZTA ageing did not seem to have a direct influence on the roughness. The ageing increased the wear volumes of ZTA and it was fou...

  6. Pengaruh Pemasukan Alumina Terhadap Operasi Tungku Reduksi di PT. Inalum Kuala Tanjung

    OpenAIRE

    Sudjana, Putra Eka

    2015-01-01

    Produksi aluminium cair di PT INALUM memerlukan bahan baku utama berupa alumina (Al2O3). Pemasukan alumina (Al2O3) mempunyai dua metode yaitu Regular Feeding dan Demand Feeding. Metode demand feeding yang digunakan yaitu pemasukan alumina (Al2O3) berdasarkan kebutuhan . Konsentrasi alumina (Al2O3) pada operasi tungku reduksi berkisar antara 2% - 4%. Konsentrasi alumina (Al2O3) < 1% akan menyebabkan terjadinya efek anoda atau anode effect (AE) dan konsentrasi alumina (Al2O3) ...

  7. Sulfuric Acid and Ammonium Sulfate Leaching of Alumina from Lampang Clay

    OpenAIRE

    Numluk, Paweena; Chaisena, Aphiruk

    2012-01-01

    The rapid development of the global alumina industry has led to a considerable increase in the production alumina and processing of alumina from non-bauxitic sources. Lampang clays comprise various minerals that contain about 22.70 wt% of extractable alumina. Local clay was ground, activated by calcination and treated with sulfuric acid to extract alumina. In the activation step, the effects of temperature and time on the extraction of alumina and iron were investigated. The leaching experime...

  8. Capillary hemangioma of palatal mucosa

    OpenAIRE

    Bharti, Vipin; Singh, Jagmohan

    2012-01-01

    Hemangiomas are common tumors characterized microscopically by proliferation of blood vessels. The congenital hemangioma is often present at birth and may become more apparent throughout life. They are probably developmental rather than neoplastic in origin. Despite their benign origin and behavior, hemangiomas in the oral cavity are always of clinical importance to the dental profession and require appropriate clinical management. This case report presents a case of capillary hemangioma of a...

  9. Exponential asymptotics and capillary waves

    OpenAIRE

    Chapman, S. J.; Vanden-Broeck, J.

    2002-01-01

    Recently developed techniques in exponential asymptotics beyond all orders are employed on the problem of potential flows with a free surface and small surface tension, in the absence of gravity. Exponentially small capillary waves are found to be generated on the free surface where the equipotentials from singularities in the flow (for example, stagnation points and corners) meet it. The amplitude of these waves is determined, and the implications are considered for many quite general flows....

  10. Nonlinear waves in capillary electrophoresis

    OpenAIRE

    Ghosal, Sandip; Chen, Zhen

    2012-01-01

    Electrophoretic separation of a mixture of chemical species is a fundamental technique of great usefulness in biology, health care and forensics. In capillary electrophoresis the sample migrates in a microcapillary in the presence of a background electrolyte. When the ionic concentration of the sample is sufficiently high, the signal is known to exhibit features reminiscent of nonlinear waves including sharp concentration ‘shocks’. In this paper we consider a simplified model consisting of a ...

  11. Inertial Rise in Short Capillaries

    CERN Document Server

    Shardt, Orest; Derksen, J J; Mitra, Sushanta K

    2013-01-01

    In this fluid dynamics video we show capillary rise experiments with diethyl ether in short tubes. The height of each short tube is less than the maximum height the liquid can achieve, and therefore the liquid reaches the top of the tube while still rising. Over a narrow range of heights, the ether bulges out from the top of the tube and spreads onto the external wall.

  12. Evaluation of BICRON NE MCP DXT-RAD passive extremity dosemeter

    CERN Document Server

    Yuen, P S; Frketich, G; Rotunda, J

    1999-01-01

    Passive extremity dosemeters currently used in dosimetry communities worldwide have shortcomings. In general, an extremity dosemeter has too thick a detector element, and the dosemeter response is highly energy dependent for beta rays with energies ranging from 200 keV to 2 MeV. It often does not have dosemeter identification, causing problems in the chain of custody. It is often read manually, rendering reading/packing operations very labour intensive. As a result of collaboration between AECL and BICRON NE, a new extremity dosemeter, incorporating a highly sensitive LiF:Mg,Cu,P TLD and tentatively code named MCP DXT-RAD, was developed. It has been evaluated for radiological performance against an ISO draft standard for extremity dosemeters in twelve categories: homogeneity, detection threshold, beta ray energy response, beta angular response, photon energy response, photon angular response, reproducibility, stability under various climatic conditions, linearity, residue, self irradiation, and effect of ligh...

  13. Cosmology and the Hubble Constant: On the Megamaser Cosmology Project (MCP)

    CERN Document Server

    Henkel, C; Reid, M J; Condon, J J; Lo, K Y; Impellizzeri, C M V; Kuo, C Y

    2012-01-01

    The Hubble constant Ho describes not only the expansion of local space at redshift z ~ 0, but is also a fundamental parameter determining the evolution of the universe. Recent measurements of Ho anchored on Cepheid observations have reached a precision of several percent. However, this problem is so important that confirmation from several methods is needed to better constrain Ho and, with it, dark energy and the curvature of space. A particularly direct method involves the determination of distances to local galaxies far enough to be part of the Hubble flow through water vapor (H2O) masers orbiting nuclear supermassive black holes. The goal of this article is to describe the relevance of Ho with respect to fundamental cosmological questions and to summarize recent progress of the the `Megamaser Cosmology Project' (MCP) related to the Hubble constant.

  14. Treelike networks accelerating capillary flow

    Science.gov (United States)

    Shou, Dahua; Ye, Lin; Fan, Jintu

    2014-05-01

    Transport in treelike networks has received wide attention in natural systems, oil recovery, microelectronic cooling systems, and textiles. Existing studies are focused on transport behaviors under a constant potential difference (including pressure, temperature, and voltage) in a steady state [B. Yu and B. Li, Phys. Rev. E 73, 066302 (2006), 10.1103/PhysRevE.73.066302; J. Chen, B. Yu, P. Xu, and Y. Li, Phys. Rev. E 75, 056301 (2007), 10.1103/PhysRevE.75.056301]. However, dynamic (time-dependent) transport in such systems has rarely been concerned. In this work, we theoretically investigate the dynamics of capillary flow in treelike networks and design the distribution of radius and length of local branches for the fastest capillary flow. It is demonstrated that capillary flow in the optimized tree networks is faster than in traditional parallel tube nets under fixed constraints. As well, the flow time of the liquid is found to increase approximately linearly with penetration distance, which differs from Washburn's classic description that flow time increases as the square of penetration distance in a uniform tube.

  15. IMPROVED CORROSION RESISTANCE FOR ALUMINA REFRACTORY

    Energy Technology Data Exchange (ETDEWEB)

    John P. Hurley; Patty L. Kleven

    1999-04-30

    In order to increase the efficiency of advanced coal-fired power systems, higher working fluid temperatures must be reached. Some system surfaces will have to be protected by covering them with corrosion-resistant refractories. Corrosion is the degradation of the material surfaces or grain boundaries by chemical reactions with melts, liquids, or gases causing loss of material and, consequently, a decrease in the strength of the structure. In order to develop methods of reducing corrosion, the microstructure that is attacked must be identified along with the mechanism and rates of attack. Earlier tests with several commercially available high-temperature castable refractories showed that the fused-alumina aggregate grains within the materials had the highest corrosion resistance of any of the castable materials. However, the cement holding the grains was easily attacked. Therefore, to improve the corrosion resistance and thermomechanical properties of alumina-based refractories, we attempted to change the cement to a more corrosion- and erosion-resistant bonding material through the addition of rare-earth oxides (REO). Phase diagrams were used to identify stable high-melting-temperature materials within the lanthanide-alumina series that could modify the bonding phase of the alumina-based refractory. Two mechanisms of reducing corrosion were investigated. One was the formation of corrosion-resistant layers within the refractory. The other was increased sintering to increase strength and seal continuous pores that would reduce slag penetration. Garnets (Re{sub 3}Al{sub 5}O{sub 12}) and perovskites (ReAl{sub 2}O{sub 3}), where Re is the REO, are two of the stable high-melting-temperature materials identified that were believed could be formed in the refractory matrix to help reduce corrosion rates. For the base refractory, Plicast 99 made by Plibrico was chosen. It is a 99% alumina castable composed of fused alumina aggregate and a cement made primarily from Alphabond

  16. Progression of Diabetic Capillary Occlusion: A Model.

    Directory of Open Access Journals (Sweden)

    Xiao Fu

    2016-06-01

    Full Text Available An explanatory computational model is developed of the contiguous areas of retinal capillary loss which play a large role in diabetic maculapathy and diabetic retinal neovascularization. Strictly random leukocyte mediated capillary occlusion cannot explain the occurrence of large contiguous areas of retinal ischemia. Therefore occlusion of an individual capillary must increase the probability of occlusion of surrounding capillaries. A retinal perifoveal vascular sector as well as a peripheral retinal capillary network and a deleted hexagonal capillary network are modelled using Compucell3D. The perifoveal modelling produces a pattern of spreading capillary loss with associated macular edema. In the peripheral network, spreading ischemia results from the progressive loss of the ladder capillaries which connect peripheral arterioles and venules. System blood flow was elevated in the macular model before a later reduction in flow in cases with progression of capillary occlusions. Simulations differing only in initial vascular network structures but with identical dynamics for oxygen, growth factors and vascular occlusions, replicate key clinical observations of ischemia and macular edema in the posterior pole and ischemia in the retinal periphery. The simulation results also seem consistent with quantitative data on macular blood flow and qualitative data on venous oxygenation. One computational model applied to distinct capillary networks in different retinal regions yielded results comparable to clinical observations in those regions.

  17. NMR Revealed Activated Alumina-Water Interaction

    Institute of Scientific and Technical Information of China (English)

    ZHOU Rui; ZHOU Yan; HU Kai; JI Zhen-ping; CHENG Gong-zhen

    2005-01-01

    Three different spin-lattice relaxation times (T1) of water were obtained in activated alumina-water slurry system, which indicate that there exist three states of water: bound water, pore water and bulk water. The chemical shift (δH) decreases as the amount of water added to the system increases due to the differences in contribution of these three states of water in the samples. The δH value for adsorbed water decreases nearly linearly and T1 increases with elevating temperature, which result from the decrease in the content of bound water by the increase in thermal motion.

  18. Improved Synthesis Of Potassium Beta' '-Alumina

    Science.gov (United States)

    Williams, Roger M.; Jeffries-Nakamura, Barbara; Ryan, Margaret A.; O'Connor, Dennis E.; Kisor, Adam; Underwood, Mark

    1996-01-01

    Improved formulations of precursor materials synthesize nearly-phase-pure potassium beta' '-alumina solid electrolyte (K-BASE) powder. Materials are microhomogeneous powders (or, alternatively, gels) containing K(+,) Mg(2+), and Al(3+). K-BASE powder produced used in potassium-working-fluid alkali-metal thermal-to-electric conversion (K-AMTEC), in which heat-input and heat-rejection temperatures lower than sodium-working-fluid AMTEC (Na-AMTEC). Additional potential use lies in purification of pottassium by removal of sodium and calcium.

  19. Conduction mechanism of single-crystal alumina

    Science.gov (United States)

    Will, Fritz G.; Delorenzi, Horst G.; Janora, Kevin H.

    1992-01-01

    The fully guarded three-terminal technique was used to perform conductivity measurements on single-crystal alumina at temperatures of 400-1300 C. The conductivity was also determined as a function of time at various temperatures and applied fields. Further, the fractions of the current carried by Al and O ions (ionic transference numbers) were determined from long-term transference experiments in the temperature range 1100-1300 C. A mathematical model of the conduction mechanism is proposed, and model predictions are compared with experimental results.

  20. Nanotube Arrays in Porous Anodic Alumina Membranes

    Institute of Scientific and Technical Information of China (English)

    Liang LI; Naoto KOSHIZAKI; Guanghai LI

    2008-01-01

    This review summarizes the various techniques developed for fabricating nanotube arrays in porous anodic alumina membranes (AAMs). After a brief introduction to the fabrication process of AAMs, taking carbons, metals, semiconductors, organics, biomoleculars, and heterojunctions as typical examples, attention will be focused on the recently established methods to fabricate nanotubes in AAM, including electrochemical deposition, surface sol-gel, modified chemical vapor deposition, atomic layer deposition, and layer-by-layer growth. Every method is demonstrated by one or two reported results. Finally, this review is concluded with some perspectives on the research directions and focuses on the AAM-based nanotubes fields.

  1. Differential suppression of ethylene biosynthesis and receptor genes in 'Golden Delicious' apple by preharvest and postharvest 1-MCP treatments

    Science.gov (United States)

    Harvista™, a spraying formulation of 1-MCP, is a recently available tool for managing preharvest on-tree fruit maturation whereas SmartFresh™ is the widely-used treatment for postharvest handling and storage. In the current study, the timing of pre-harvest application and its effects on fruit ripeni...

  2. Effectiveness of 1-Methylcyclopropene (1-MCP Combination with Nisin-EDTA Treatment of Fresh-cut Kiwifruit for Prevention

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2014-02-01

    Full Text Available A comprehensive study was made to determine the effects of 1-MCP (1 &muL L-1 pretreated combined with Nisin-EDTA (0.02 M on fresh-cut kiwifruit slices. Physico-chemical attributes of kiwifruit slices were evaluated every 3 days during storage. The fresh-cut kiwifruits pre-treated with 1-MCP, Nisin-EDTA coating and their combination showed better preservation quality and compared with the control slices during the entire storage period. 1-MCP showed an ability to relieve the pulp softening extent and inhibit total chlorophyll content decrease. Lower Polyphenol Oxidase (PPO and higher ascorbic acid were observed in Nisin-EDTA treated samples which also showed a less total bacteria count compared with the control in the end storage. Moreover, the combination of 1-MCP and Nisin-EDTA was more effective than individual treatment on maintaining the quality of fresh-cut kiwifruit, which suggested that this may be a healthy alternative method for fresh-cut kiwifruit.

  3. 3.5. Drying of cryolite-alumina concentrate

    International Nuclear Information System (INIS)

    This article is devoted to drying of cryolite-alumina concentrate. The drying process of cryolite-alumina concentrate at isothermal and polythermal conditions was studied. The kinetics and mechanism of the process were studied as well. The kinetics of concentrate drying under isothermal conditions was studied in air bath and results are presented.

  4. Textural stability of titania–alumina composite membranes

    NARCIS (Netherlands)

    Kumar, Krishnankutty-Nair P.; Keizer, Klaas; Burggraaf, Anthonie J.

    1993-01-01

    Textural evolution (porosity reduction, pore and crystallite growth) in titania–alumina composite membranes has been studied using thermal analysis, X-ray diffraction, field emission scanning electron microscopy and N2 physisorption techniques. The presence of alumina in the membranes improved the t

  5. Dynamic compressive and tensile strengths of spark plasma sintered alumina

    Science.gov (United States)

    Girlitsky, I.; Zaretsky, E.; Kalabukhov, S.; Dariel, M. P.; Frage, N.

    2014-06-01

    Fully dense submicron grain size alumina samples were manufactured from alumina nano-powder using Spark Plasma Sintering and tested in two kinds of VISAR-instrumented planar impact tests. In the first kind, samples were loaded by 1-mm tungsten impactors, accelerated to a velocity of about 1 km/s. These tests were aimed at studying the Hugoniot elastic limit (HEL) of Spark Plasma Sintering (SPS)-processed alumina and the decay, with propagation distance, of the elastic precursor wave. In the tests of the second kind, alumina samples of 3-mm thickness were loaded by 1-mm copper impactors accelerated to 100-1000 m/s. These tests were aimed at studying the dynamic tensile (spall) strength of the alumina specimens. The tensile fracture of the un-alloyed alumina shows a monotonic decline of the spall strength with the amplitude of the loading stress pulse. Analysis of the decay of the elastic precursor wave allowed determining the rate of the irreversible (inelastic) strains in the SPS-processed alumina at the initial stages of the shock-induced inelastic deformation and to clarify the mechanisms responsible for the deformation. The 1-% addition of Cr2O3 decreases the HEL of the SPS-processed alumina by 5-% and its spall strength by 50% but barely affects its static properties.

  6. Radiation dose determination by using powder Seydisehir alumina

    International Nuclear Information System (INIS)

    Thermoluminescence dosimeters (TLDs) is a passive dose measurement method used for the supervision, quality control and calibration during radiation dose measurements. Nowadays TLDs, including alumina, are largely used and investigated due to high sensitivity, physical and chemical stability, and re-usefulness. In this work, powder form of Seydisehir alumina is used as a thermoluminescence material and α and β radiation doses were measured.

  7. Dynamic compressive and tensile strengths of spark plasma sintered alumina

    International Nuclear Information System (INIS)

    Fully dense submicron grain size alumina samples were manufactured from alumina nano-powder using Spark Plasma Sintering and tested in two kinds of VISAR-instrumented planar impact tests. In the first kind, samples were loaded by 1-mm tungsten impactors, accelerated to a velocity of about 1 km/s. These tests were aimed at studying the Hugoniot elastic limit (HEL) of Spark Plasma Sintering (SPS)-processed alumina and the decay, with propagation distance, of the elastic precursor wave. In the tests of the second kind, alumina samples of 3-mm thickness were loaded by 1-mm copper impactors accelerated to 100–1000 m/s. These tests were aimed at studying the dynamic tensile (spall) strength of the alumina specimens. The tensile fracture of the un-alloyed alumina shows a monotonic decline of the spall strength with the amplitude of the loading stress pulse. Analysis of the decay of the elastic precursor wave allowed determining the rate of the irreversible (inelastic) strains in the SPS-processed alumina at the initial stages of the shock-induced inelastic deformation and to clarify the mechanisms responsible for the deformation. The 1-% addition of Cr2O3 decreases the HEL of the SPS-processed alumina by 5-% and its spall strength by 50% but barely affects its static properties.

  8. Depositing Adherent Ag Films On Ti Films On Alumina

    Science.gov (United States)

    Honecy, Frank S.

    1995-01-01

    Report discusses cleaning of ceramic (principally, alumina) substrates in preparation for sputter deposition of titanium intermediate films on substrates followed by sputter deposition of outer silver films. Principal intended application, substrates sliding parts in advanced high-temperature heat engines, and outer silver films serve as solid lubricants: lubricating properties described in "Solid Lubricant for Alumina" (LEW-15495).

  9. Experimental investigation of the radiation shielding efficiency of a MCP detector in the radiation environment near Jupiter's moon Europa

    Science.gov (United States)

    Tulej, M.; Meyer, S.; Lüthi, M.; Lasi, D.; Galli, A.; Piazza, D.; Desorgher, L.; Reggiani, D.; Hajdas, W.; Karlsson, S.; Kalla, L.; Wurz, P.

    2016-09-01

    Neutral Ion Mass spectrometer (NIM) is one of the instruments in the Particle Environmental Package (PEP) designed for the JUICE mission of ESA to the Jupiter system. NIM, equipped with a sensitive MCP ion detector, will conduct detailed measurements of the chemical composition of Jovian icy moons exospheres. To achieve high sensitivity of the instrument, radiation effects due to the high radiation background (high-energy electrons and protons) around Jupiter have to be minimised. We investigate the performance of an Al-Ta-Al composite stack as a potential shielding against high-energy electrons. Experiments were performed at the PiM1 beam line of the High Intensity Proton Accelerator Facilities located at the Paul Scherrer Institute, Villigen, Switzerland. The facility delivers a particle beam containing e-, μ- and π- with momentum from 17.5 to 345 MeV/c (Hajdas et al., 2014). The measurements of the radiation environment generated during the interaction of primary particles with the Al-Ta-Al material were conducted with dedicated beam diagnostic methods and with the NIM MCP detector. In parallel, modelling studies using GEANT4 and GRAS suites were performed to identify products of the interaction and predict ultimate fluxes and particle rates at the MCP detector. Combination of experiment and modelling studies yields detailed characterisation of the radiation fields produced by the interaction of the incident e- with the shielding material in the range of the beam momentum from 17.5 to 345 MeV/c. We derived the effective MCP detection efficiency to primary and secondary radiation and effective shielding transmission coefficients to incident high-energy electron beam in the range of applied beam momenta. This study shows that the applied shielding attenuates efficiently high-energy electrons. Nevertheless, owing to nearly linear increase of the bremsstrahlung production rate with incident beam energy, above 130 MeV their detection rates measured by the MCP

  10. Effect of One-methylcyclopropene (1-MCP) and chlorine dioxide (ClO2) on preservation of green walnut fruit and kernel traits

    OpenAIRE

    Jiang, Liuqing; Feng, Wenyu; Li, Fang; Xu, Jingying; Ma, Yanping; Ma, Huiling

    2013-01-01

    The effect of the ethylene receptor competitor 1-methylcyclopropene (1-MCP) and the legally approved disinfectant chlorine dioxide (ClO2) on preservation of the green walnut fruit during storage was investigated. Green Chinese walnut fruit cv. Xilin No.2 was harvested on commercial maturity and stored at 0–1 °C after the fruit was treated by water (control), 80 mg L−1ClO2 (ClO2), 0.5 μL L−11-MCP (1-MCP), or combination treatment of 80 mg L−1 ClO2 with either 0.1 μL L−1 1-MCP (0.1 1-MCP+ ClO2)...

  11. Capillary pumped loop body heat exchanger

    Science.gov (United States)

    Swanson, Theodore D. (Inventor); Wren, deceased, Paul (Inventor)

    1998-01-01

    A capillary pumped loop for transferring heat from one body part to another body part, the capillary pumped loop comprising a capillary evaporator for vaporizing a liquid refrigerant by absorbing heat from a warm body part, a condenser for turning a vaporized refrigerant into a liquid by transferring heat from the vaporized liquid to a cool body part, a first tube section connecting an output port of the capillary evaporator to an input of the condenser, and a second tube section connecting an output of the condenser to an input port of the capillary evaporator. A wick may be provided within the condenser. A pump may be provided between the second tube section and the input port of the capillary evaporator. Additionally, an esternal heat source or heat sink may be utilized.

  12. Microfluidic PMMA interfaces for rectangular glass capillaries

    International Nuclear Information System (INIS)

    We present the design and fabrication of a polymeric capillary fluidic interface fabricated by micro-milling. The design enables the use of glass capillaries with any kind of cross-section in complex microfluidic setups. We demonstrate two different designs of the interface; a double-inlet interface for hydrodynamic focusing and a capillary interface with integrated pneumatic valves. Both capillary interfaces are presented together with examples of practical applications. This communication shows the design optimization and presents details of the fabrication process. The capillary interface opens up for the use of complex microfluidic systems in single-use glass capillaries. They also enable simple fabrication of glass/polymer hybrid devices that can be beneficial in many research fields where a pure polymer chip negatively affects the device's performance, e.g. acoustofluidics. (technical note)

  13. Comparison of deep desulfurization methods in alumina production process

    Institute of Scientific and Technical Information of China (English)

    刘战伟; 李旺兴; 马文会; 尹中林; 武国宝

    2015-01-01

    Several methods of deep desulfurization in alumina production process were studied, and the costs of these methods were compared. It is found that most of the S2− in sodium aluminate solution can be removed by adding sodium nitrate or hydrogen peroxide in digestion process, and in this way the effect of S2− on alumina product quality is eliminated. However, the removal efficiency of2-23SOin sodium aluminate solution is very low by this method. Both S2− and2-23SO in sodium aluminate solution can be removed completely by wet oxidation method in digestion process. The cost of desulfurization by wet oxidation is lower than by adding sodium nitrate or hydrogen peroxide. The results of this research reveal that wet oxidation is an economical and feasible method for the removal of sulfur in alumina production process to improve alumina quality, and provide valuable guidelines for alumina production by high-sulfur bauxite.

  14. Morphology and transmittance of porous alumina on glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Guo Peitao, E-mail: guopeitao@hotmail.com [Wuhan University of Technology. Wuhan (China); Xia Zhilin [Wuhan University of Technology. Wuhan (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Xiangtan (China); Xue Yiyu [Wuhan University of Technology. Wuhan (China); Huang Caihua [China Three Gorges University, Yichang (China); Zhao Lixin [Wuhan University of Technology. Wuhan (China)

    2011-02-01

    The porous optical film has higher threshold of laser-induced damage than densified films, for the study of mechanism of laser-induced damage of porous optical film with ordered pore structure. Porous anodic alumina (PAA) film with high transmittance on glass substrate has been prepared. Aluminum film was deposited on glass substrate by means of resistance and electron beam heat (EBH) evaporation. Porous alumina was prepared in oxalic acid solution under different anodizing conditions. At normal incidence, the optical transmittance spectrum over 300-1000 nm spectra region was obtained by spectrophotometer. SEM was introduced to analysis the morphology of the porous alumina film. The pore aperture increased with the increase of anodizing voltage, which resulted in a rapid decrease of the pore concentration and the optical thickness of porous alumina film. Damage morphology of porous alumina film is found to be typically defects initiated, and the defect is the pore presented on the film.

  15. Preliminary joining experiment of alumina pipes by using ceramics sleeve

    International Nuclear Information System (INIS)

    Preliminary experiments on alumina ceramics pipes joining by using shrinkable alumina sleeve and high melting point oxide solder have been carried out. Sleeves were prepared by way of sintering at relatively low temperature to shrink 1% during following joining process. As solder, alumina-calcia system was selected and paste containing alumina and calcium carbonate powder mixture was prepared. Joining was carried out by inserting the paste between sleeve and pipes, and by heating at 1500degC in air. By the shrink of sleeve and the formation of interface by solder, it was possible to realize the joined pipe without the vacuum leakage. The airtightness of the joined alumina pipes is almost equal to it of the metal pipe welding. (author)

  16. Dispersion Caused by Carbon Dioxide During Secondary Alumina Dissolution: A Lab-Scale Research

    Science.gov (United States)

    Yang, Youjian; Gao, Bingliang; Wang, Zhaowen; Shi, Zhongning; Hu, Xianwei; Yu, Jiangyu

    2014-06-01

    Secondary alumina is the byproduct of dry scrubbing in aluminum smelting. Secondary alumina has superior dissolution characteristics to primary alumina. Secondary alumina dissolves in pieces in molten cryolite, which results in larger contact area and better diffusion kinetics. In this work, the dissolution phenomenon of primary alumina, secondary alumina, and primary alumina doped with sodium carbonate or calcium carbonate (mass ratio = 10:1, 20:1) was observed and compared to estimate carbon-induced dispersion in industrial secondary alumina. Temperature fluctuations during sample dissolution were measured to evaluate the benefits of preheating on alumina dissolution. It was found that carbon mixed in secondary alumina significantly influences the dispersion of alumina particles at the moment of feeding, and thermodynamic analysis also shows that the combustion heat from carbon facilitates dispersion.

  17. Signal pathways underlying homocysteine-induced production of MCP-1 and IL-8 in cultured human whole blood

    Institute of Scientific and Technical Information of China (English)

    Xiao-kun ZENG; You-fei GUAN; Daniel G REMICK; Xian WANG

    2005-01-01

    Aim: To elucidate the mechanisms underlying homocysteine (Hcy)-induced chemokine production. Methods: Human whole blood was pretreated with inhibitors of calmodulin (CaM), protein kinase C (PKC), protein tyrosine kinase(PTK), mitogen-activated protein kinase (MAPK), and NF-κB and activators of PPARγ for 60 min followed by incubation with Hcy 100 μmol/L for 32 h. The levels of mitogen chemokine protein (MCP)-1 and interleukin-8 (IL-8) were determined by enzyme-linked immunosorbant assay (ELISA). Results: Inhibitors of PKC (calphostin C, 50-500 nmol/L and RO-31-8220, 10-100 nmol/L), CaM(W7, 28-280 μmol/L), ERK1/2 MAPK (PD 98059, 2-20 μmol/L), p38 MAPK(SB 203580, 0.6-6 μmol/L), JNK MAPK (curcumin, 2-10 μmol/L), and NF-κB(PDTC, 10-100 nmol/L) markedly reduced Hcy 100 μmol/L-induced production of MCP-1 and IL-8 in human cultured whole blood, but the inhibitors of PTK(genistein, 2.6-26 μmol/L and tyrphostin, 0.5-5 μmol/L) had no obvious effect on MCP-1 and IL-8 production. PPARγ activators (ciglitazone 30 μmol/L and troglitazone 10 μmol/L) depressed the Hcy-induced MCP-1 production but not IL-8 production in the cultured whole blood. Conclusion: Hcy-induced MCP-1 and IL-8 production is mediated by activated signaling pathways such as PKC,CaM, MAPK, and NF-κB. Our results not only provide clues for the signal transduction pathways mediating Hcy-induced chemokine production, but also offer a plausible explanation for a pathogenic role of hyperhomocysteinemia in these diseases.

  18. FGFR3 promotes angiogenesis-dependent metastasis of hepatocellular carcinoma via facilitating MCP-1-mediated vascular formation.

    Science.gov (United States)

    Liu, Xinyu; Jing, Xiaoqian; Cheng, Xi; Ma, Ding; Jin, Zhijian; Yang, Weiping; Qiu, Weihua

    2016-05-01

    The biological role of fibroblast growth factor receptor 3 (FGFR3) in tumor angiogenesis of hepatocellular carcinoma (HCC) has not been discussed before. Our previous work had indicated FGFR3 was overexpressed in HCC, and silencing FGFR3 in Hu7 cells could regulate tumorigenesis via down-regulating the phosphorylation level of key members of classic signaling pathways including ERK and AKT. In the present work, we explored the role of FGFR3 in angiogenesis-dependent metastasis by using SMMC-7721 and QGY-7703 stable cell lines. Our results indicated FGFR3 could regulate in vitro cell migration ability and in vivo lung metastasis ability of HCC, which was in accordance with increased angiogenesis ability in vitro and in vivo. Using the supernatant from SMMC-7721/FGFR3 cells, we conducted a human angiogenesis protein microarray including 43 angiogenesis factors and found that FGFR3 modulated angiogenesis and metastasis of HCC mainly by promoting the protein level of monocyte chemotactic protein 1 (MCP-1). Silencing FGFR3 by short hairpin RNA (shRNA) could reduce MCP-1 level in lysates and supernatant of QGY-7703 cells and SMMC-7721 cells. Silencing MCP-1 in QGY-7703 or SMMC-7721 cells could induce similar phenotypes compared with silencing FGFR3. Our results suggested FGFR3 promoted metastasis potential of HCC, at least partially if not all, via facilitating MCP-1-mediated angiogenesis, in addition to previously found cell growth and metastasis. MCP-1, a key medium between HCC cells and HUVECs, might be a novel anti-vascular target in HCC. PMID:27044356

  19. DNA Sequencing Using capillary Electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Barry Karger

    2011-05-09

    The overall goal of this program was to develop capillary electrophoresis as the tool to be used to sequence for the first time the Human Genome. Our program was part of the Human Genome Project. In this work, we were highly successful and the replaceable polymer we developed, linear polyacrylamide, was used by the DOE sequencing lab in California to sequence a significant portion of the human genome using the MegaBase multiple capillary array electrophoresis instrument. In this final report, we summarize our efforts and success. We began our work by separating by capillary electrophoresis double strand oligonucleotides using cross-linked polyacrylamide gels in fused silica capillaries. This work showed the potential of the methodology. However, preparation of such cross-linked gel capillaries was difficult with poor reproducibility, and even more important, the columns were not very stable. We improved stability by using non-cross linked linear polyacrylamide. Here, the entangled linear chains could move when osmotic pressure (e.g. sample injection) was imposed on the polymer matrix. This relaxation of the polymer dissipated the stress in the column. Our next advance was to use significantly lower concentrations of the linear polyacrylamide that the polymer could be automatically blown out after each run and replaced with fresh linear polymer solution. In this way, a new column was available for each analytical run. Finally, while testing many linear polymers, we selected linear polyacrylamide as the best matrix as it was the most hydrophilic polymer available. Under our DOE program, we demonstrated initially the success of the linear polyacrylamide to separate double strand DNA. We note that the method is used even today to assay purity of double stranded DNA fragments. Our focus, of course, was on the separation of single stranded DNA for sequencing purposes. In one paper, we demonstrated the success of our approach in sequencing up to 500 bases. Other

  20. A New Conductivity Detector for Capillary Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new conductivity detector for capillary electrophoresis consisting of an electrochemical cell and a conductive meter was developed. In the cell, the microelectrode and capillary were inserted through the cell wall and fixed by screws and sealing ring, the ends of microelectrode and capillary were located by a guide with two cross holes. LOD for K+ was 1.5×10-5 mol/L.

  1. Serum proteins analysis by capillary electrophoresis

    OpenAIRE

    Uji, Yoshinori; Okabe, Hiroaki

    2001-01-01

    The purpose of this study was to evaluate the efficacy of multi-capillary electrophoresis instrument in clinical laboratory. An automated clinical capillary electrophoresis system was evaluated for performing serum proteins electrophoresis and immuno-fixation electrophoresis by subtraction. In this study the performance of capillary electrophoresis was compared with the cellulose acetate membrane electrophoresis and agarose gel immunofixation electrophoresis for serum proteins. The results of...

  2. Cytokine Analysis by Immunoaffinity Capillary Electrophoresis

    OpenAIRE

    Mendonca, Mark; Kalish, Heather

    2013-01-01

    Immunoaffinity capillary electrophoresis (ICE) is a powerful tool used to detect and quantify target proteins of interest in complex biological fluids. The target analyte is captured and bound to antibodies immobilized onto the wall of a capillary, labeled in situ with a fluorescent dye, eluted and detected online using laser-induced fluorescence following electrophoretic separation. Here, we illustrate how to construct an immunoaffinity capillary and utilize it to run ICE in order to capture...

  3. Modified-starch Consolidation of Alumina Ceramics

    Institute of Scientific and Technical Information of China (English)

    JU Chenhui; WANG Yanmin; YE Jiandong; HUANG Yun

    2008-01-01

    The alumina ceramics with the homogeneous microstructure and the higher density were fabricated via the modified-starch consolidation process by 1.0 wt%of a modified starch as a consolidator/binder.The swelling behavior of the modified oxidized tapioca starch was analyzed by optical microscope,and two other corn starches(common corn starch and high amylose COrn starch)were also analyzed for comparison.The modified starch used as a binder for the consolidation swelled at about 55℃.began to gelatinize at 65℃ and then was completely gelatinized at 75℃.But the corn starches could not be completely gelatinized even at 80℃for 1 h.The high-strength green bodies(10.6 MPa)with the complex shapes were produced.The green bodies were sintered without any binder burnout procedure at 1700℃and a relative density of 95.3% was obtained for the sintered bodies,which is similar to that of the sintered sample formed by conventional slip casting.In addition,the effect of temperature on the apparent viscosity of the starch/alumina slurry in the process was investigated,and the corresponding mechanism for the starch consolidation was discussed.

  4. Properties of Transition Metal Doped Alumina

    Science.gov (United States)

    Nykwest, Erik; Limmer, Krista; Brennan, Ray; Blair, Victoria; Ramprasad, Rampi

    Crystallographic texture can have profound effects on the properties of a material. One method of texturing is through the application of an external magnetic field during processing. While this method works with highly magnetic systems, doping is required to couple non-magnetic systems with the external field. Experiments have shown that low concentrations of rare earth (RE) dopants in alumina powders have enabled this kind of texturing. The magnetic properties of RE elements are directly related to their f orbital, which can have as many as 7 unpaired electrons. Since d-block elements can have as many as 5 unpaired electrons the effects of substitutional doping of 3d transition metals (TM) for Al in alpha (stable) and theta (metastable) alumina on the local structure and magnetic properties, in addition to the energetic cost, have been calculated by performing first-principles calculations based on density functional theory. This study has led to the development of general guidelines for the magnetic moment distribution at and around the dopant atom, and the dependence of this distribution on the dopant atom type and its coordination environment. It is anticipated that these findings can aid in the selection of suitable dopants help to guide parallel experimental efforts. This project was supported in part by an internship at the Army Research Laboratory, administered by the Oak Ridge Institute for Science and Education, along with a grant of computer time from the DoD High Performance Computing Modernization Program.

  5. Combination for electrolytic reduction of alumina

    Science.gov (United States)

    Brown, Craig W.; Brooks, Richard J.; Frizzle, Patrick B.; Juric, Drago D.

    2002-04-30

    An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises molten electrolyte having the following ingredients: AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound is, a fluoride; oxide, or carbonate. The metal is nickel, iron, copper, cobalt, or molybdenum. The bath is employed in a combination including a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the instant bath during electrolytic reduction of alumina to aluminum improves the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

  6. Lightweight alumina refractory aggregate. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Swansiger, T.G.; Pearson, A.

    1996-07-16

    Objective was to develop a lightweight, high alumina refractory aggregate for use in various high performance insulating (low thermal conductivity) refractory applications (e.g., in the aluminium, glass, cement, and iron and steel industries). A new aggregate process was developed through bench and pilot-scale experiments involving extrusion of a blend of calcined and activated alumina powders and organic extrusion aids and binders. The aggregate, with a bulk density approaching 2.5 g/cc, exhibited reduced thermal conductivity and adequate fired strength compared to dense tabular aggregate. Refractory manufacturers were moderately enthusiastic over the results. Alcoa prepared an economic analysis for producing lightweight aggregate, based on a retrofit of this process into existing Alcoa production facilities. However, a new, competing lightweight aggregate material was developed by another company; this material (Plasmal{trademark})had a significantly more favorable cost base than the Alcoa/DOE material, due to cheap raw materials and fewer processing steps. In late 1995, Alcoa became a distributor of Plasmal. Alcoa estimated that {ge}75% of the market originally envisioned for the Alcoa/DOE aggregate would be taken by Plasmal. Hence, it was decided to terminate the contract without the full- scale demonstration.

  7. Ultrasonic analysis of sintered alumina pellets

    International Nuclear Information System (INIS)

    Uranium dioxide pellets are used as fuel in Pressurized Water Reactors. These pellets require some degree of porosity to accommodate fission products generated during the burning of fuel. It is usual to utilize the Archimedes method to determine the sintered pellet porosity. For the determination of closed pores, samples of pellets need to be analyzed using micrography to calculate the distribution of the pores. The ultrasonic group of the Nuclear Engineering Institute (IEN) is developing a nondestructive characterization through ultrasonic technique in the frequency domain, this technique will permit to minimize the time for determination of porosity and increase the accuracy of measurement using only one technique, taking into account pores open and closed, and to be capable to analyze 100% of the pellets. Several studies have been conducted in order to validate this method. In this work, the frequency spectrum from alumina pellets were obtained by a 5MHz frequency transducer and by means of scanning electron microscope (SEM), it was possible to investigate the interior of the material and to associate its structure to the behavior of the ultrasonic wave. Each sintering temperature showed a characteristic ultrasonic signal that could be associated with the Alumina porosity. This result showed that this method is very sensitive to the pore distribution in the material because, even within the same temperature group, variations occurred according to distribution of pore sizes. (author)

  8. Slope wavenumber spectrum models of capillary and capillary-gravity waves

    Institute of Scientific and Technical Information of China (English)

    贾永君; 张杰; 王岩峰

    2010-01-01

    Capillary and capillary-gravity waves possess a random character, and the slope wavenumber spectra of them can be used to represent mean distributions of wave energy with respect to spatial scale of variability. But simple and practical models of the slope wavenumber spectra have not been put forward so far. In this article, we address the accurate definition of the slope wavenumber spectra of water surface capillary and capillary-gravity waves. By combining the existing slope wavenumber models and using th...

  9. The expression of chemokine MCP-1 in colorectal carcinoma and its relationship to the infiltration of macrophage%结直肠癌趋化因子MCP-1的表达及其与巨噬细胞浸润的关系

    Institute of Scientific and Technical Information of China (English)

    杨春康; 陈道达; 黄凯

    2006-01-01

    Objective: To study the expression of MCP-1 in colorectal carcinoma and its relationship to the infiltration of the macrophage and to the biological behaviour of infiltration and metastasis of colorectal carcinoma.Methods: The expression of the MCP-1 mRNAwas assessed in colorectal carcinoma collected freshly from surgical specimen by RT-PCR and the expression of the MCP-1 protein was assessed in colorectal carcinoma collected from surgical specimen by immunohistochemistry.The tumor infiltrating cell and macrophage were also investigated by immunohistochemistry.Results: All the 12 specimens of colorectal carcinoma detected by RT-PCR expressed the MCP-1 mRNA; MCP-1 protein was detected in 90% (36/40) cases of the tumor; The expression of the MCP-1 protein in colorectal carcinoma correlated negatively with its state of metastasis and the Dukes' stage.But a postive correlation was found between the expression of MCP-1 and the infiltrated macrophage.The stronger expression of MCP-1,the more number of the infiltrated macrophage.Conclusion: The expression of chemokine MCP-1 in colorectal carcinoma may influence its biological behaviour of infiltration and metastasis,and can attract the immuno-cell to the local of the tumor,such as Macrophage.

  10. Amadurecimento de pêssegos 'Rubidoux' em resposta à presença de pressões parciais de CO2 durante o tratamento com 1-MCP Ripening of 'Rubidoux' peaches in response to partial pressures of CO2 exposure during the treatment with 1-MCP

    Directory of Open Access Journals (Sweden)

    Cristiano André Steffens

    2009-11-01

    Full Text Available Algumas pesquisas citam que o breve retardo no amadurecimento de pêssego tratados com 1-MCP decorre do acúmulo de CO2 durante o tratamento; contudo, o efeito do 1-MCP pode ser prejudicado pela presença do CO2. O objetivo deste trabalho foi avaliar o efeito de pressões parciais de CO2 durante a aplicação de 1-MCP (1µL L-1 e da reaplicação de 1-MCP (1µL L-1, para controlar o amadurecimento de pêssegos 'Rubidoux'. Os tratamentos avaliados foram: sem aplicação de 1-MCP + 0,1kPa de CO2; 1-MCP + 0,1kPa de CO2; 1-MCP + 2,5kPa de CO2; 1-MCP + 7,5kPa de CO2; e aplicações diárias de 1-MCP por quatro dias + 0,1kPa de CO2. O aumento nas pressões parciais de CO2 durante a aplicação do 1-MCP diminuiu a sua eficiência na redução das taxas respiratória e de produção de etileno e no retardamento da perda de firmeza da polpa e da cor verde da epiderme dos frutos. Os teores de sólidos solúveis e de acidez titulável não foram influenciados pelos tratamentos. O efeito do 1-MCP sobre o amadurecimento em pêssegos 'Rubidoux', determinado por meio do amolecimento e pela alteração da cor, é anulado pelo avanço do tempo após o tratamento, possivelmente pela biossíntese de novos receptores ao etileno.Some literatures mention that the retard ripening of peaches 1-MCP-treated is due to accumulation of CO2 during the application of 1-MCP, however the effect of the 1-MCP can be inhibited by CO2.The objectives of this research were to evaluate the effect of partial pressure of CO2, during the treatment with 1-MCP (1µL L-1, as well as the reapplication with 1-MCP (1µL L-1, on ripening 'Rubidoux' peaches. The treatments evaluated were: without 1-MCP + 0.1kPa of CO2; 1-MCP + 0.1kPa of CO2; 1-MCP + 2.5kPa of CO2; 1-MCP + 7.5kPa of CO2; and daily applications of 1-MCP for four days + 0.1kPa of CO2. The increase of CO2 partial pressure during the treatment with 1-MCP reduced its efficiency in reducing respiration and ethylene production rates and

  11. Electromigration dispersion in Capillary Electrophoresis

    CERN Document Server

    Chen, Zhen; 10.1007/s11538-011-9708-7

    2012-01-01

    In a previous paper (S. Ghosal and Z. Chen Bull. Math. Biol. 2010, vol. 72, pg. 2047) it was shown that the evolution of the solute concentration in capillary electrophoresis is described by a nonlinear wave equation that reduced to Burger's equation if the nonlinearity was weak. It was assumed that only strong electrolytes (fully dissociated) were present. In the present paper it is shown that the same governing equation also describes the situation where the electrolytic buffer consists of a single weak acid (or base). A simple approximate formula is derived for the dimensionless peak variance which is shown to agree well with published experimental data.

  12. Microbeam-coupled capillary electrophoresis

    International Nuclear Information System (INIS)

    Within the first few microseconds following a charged particle traversal of a cell, numerous oxygen and nitrogen radicals are formed along the track. Presented here is a method, using capillary electrophoresis, for simultaneous measurement, within an individual cell, of specific reactive oxygen species, such as the superoxide radical (O2-*) as well as the native and oxidised forms of glutathione, an ubiquitous anti-oxidant that assists the cell in coping with these species. Preliminary data are presented as well as plans for integrating this system into the charged particle microbeam at Columbia University. (authors)

  13. Capillary electrophoresis theory and practice

    CERN Document Server

    Grossman, Paul D

    1992-01-01

    This book is designed to be a practical guide, used by wide audience, including those new to CE, those more experienced, routine users, those interested in technology development, and those involved with applications research. References have been emphasized to allow the reader to explore the detailed specifics and theoretical foundations.This book draws together the rapidly evolving, diverse, and multidisciplinary subject of capillary electrophoresis (CE). It is designed as a practical guide to be used by a wide audience, including those new to CE as well as more experienced users. T

  14. Exotic containers for capillary surfaces

    Science.gov (United States)

    Concus, Paul; Finn, Robert

    1991-01-01

    This paper discusses 'exotic' rotationally symmetric containers that admit an entire continuum of distinct equilibrium capillary free surfaces. The paper extends earlier work to a larger class of parameters and clarifies and simplifies the governing differential equations, while expressing them in a parametric form appropriate for numerical integration. A unified presentation suitable for both zero and nonzero gravity is given. Solutions for the container shapes are depicted graphically along with members of the free-surface continuum, and comments are given concerning possible physical experiments.

  15. Terbium luminescence in alumina xerogel fabricated in porous anodic alumina matrix under various excitation conditions

    International Nuclear Information System (INIS)

    Terbium-doped alumina xerogel layers are synthesized by the sol-gel method in pores of a porous anodic alumina film 1 μm thick with a pore diameter of 150–180 nm; the film is grown on a silicon substrate. The fabricated structures exhibit terbium photoluminescence with bands typical of trivalent terbium terms. Terbium X-ray luminescence with the most intense band at 542 nm is observed for the first time for such a structure. Morphological analysis of the structure by scanning electron microscopy shows the presence of xerogel clusters in pore channels, while the main pore volume remains unfilled and pore mouths remain open. The data obtained confirm the promising applications of fabricated structures for developing matrix converters of X-rays and other ionizing radiations into visible light. The possibilities of increasing luminescence intensity in the matrix converter are discussed.

  16. Microstructural evolution of alumina-zirconia nanocomposites; Evolucao microestrutural de nanocompositos alumina-zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Ojaimi, C.L.; Chinelatto, A.S.A.; Chinelatto, A.L. [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil); Pallone, E.M.J.A., E-mail: christianelago@yahoo.com.br [Universidade de Sao Paulo (USP), Pirassununga, Sao Paulo, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos

    2012-07-01

    Ceramic materials have limited use due to their brittleness. The inclusion of nanosized particles in a ceramic matrix, which are called nanocomposites, and ceramic processing control by controlling the grain size and densification can aid in obtaining ceramic products of greater strength and toughness. Studies showed that the zirconia nano inclusions in the matrix of alumina favors an increase in mechanical properties by inhibiting the grain growth of the matrix and not by the mechanism of the transformation toughening phase of zirconia. In this work, the microstructural evolution of alumina nanocomposites containing 15% by volume of nanometric zirconia was studied. From the results it was possible to understand the sintering process of these nanocomposites. (author)

  17. Dissolution kinetics for alumina in cryolite melts. Distribution of alumina in the electrolyte of industrial aluminium cells

    Energy Technology Data Exchange (ETDEWEB)

    Kobbeltvedt, Ove

    1997-12-31

    This thesis contributes to the understanding of which factors determine the rate of dissolution of alumina added to the bath in alumina reduction cells. Knowing this may help reduce the occurrences of operation interruptions and thus make it possible to produce aluminium using less energy. When alumina powder was added to a stirred cryolite melt, the alumina dissolved in two distinct main stages. In the first stage, the dissolution rate was very high, which reflects dissolution of single alumina grains that are being dispersed in the bath upon addition. In the second stage, lumps of alumina infiltrated with bath dissolved at a rate considerably slower than that of the first stage. The formation of these alumina agglomerates is the most important contributor to slow dissolution. The parameters varied in the experiments were convection, batch size, and temperature of the bath and of the added alumina. Increased gas stirring of the bath speeded up dissolution in both stages but the size of the batch was of little significance. Increasing the bath temperature had no effect in the first stage but speeded up dissolution considerably in the second stage. Compared to adding alumina at room temperature, preheating it to a high temperature (600 {sup o}C) increased the dissolution rate in the first stage while preheating to lower temperatures (100-300 {sup o}C) decreased the dissolution rate. In the second stage, preheating slowed the dissolution. The two latter phenomena of reduced dissolution rates are ascribed to the removal of moisture from the alumina upon preheating. The bath flow and the distribution of alumina in the bath were measured in four different types of cells. It was found that if a certain asymmetry of the magnetic field traverse to the cell was present, due to the presence of risers, then loops of high velocity bath flow occurred near the short ends of the cell. Thus, alumina added near the short ends is effectively transferred away from the feeding

  18. Duality of n-3 Polyunsaturated Fatty Acids on Mcp-1 Expression in Vascular Smooth Muscle: A Potential Role of 4-Hydroxy Hexenal

    Directory of Open Access Journals (Sweden)

    Kohji Nagayama

    2015-09-01

    Full Text Available N-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA have protective effects against atherosclerosis. Monocyte chemotactic protein (MCP-1 is a major inflammatory mediator in the progression of atherosclerosis. However, little is known about the regulation of MCP-1 by DHA and EPA in vessels and vascular smooth muscle cells (VSMCs. In this study, we compared the effect of DHA and EPA on the expression of Mcp-1 in rat arterial strips and rat VSMCs. DHA, but not EPA, suppressed Mcp-1 expression in arterial strips. Furthermore, DHA generated 4-hydroxy hexenal (4-HHE, an end product of n-3 polyunsaturated fatty acids (PUFAs, in arterial strips as measured by liquid chromatography-tandem mass spectrometry. In addition, 4-HHE treatment suppressed Mcp-1 expression in arterial strips, suggesting 4-HHE derived from DHA may be involved in the mechanism of this phenomenon. In contrast, Mcp-1 expression was stimulated by DHA, EPA and 4-HHE through p38 kinase and the Keap1-Nuclear factor erythroid-derived 2-like 2 (Nrf2 pathway in VSMCs. In conclusion, there is a dual effect of n-3 PUFAs on the regulation of Mcp-1 expression. Further study is necessary to elucidate the pathological role of this phenomenon.

  19. Crystallization and crystallographic analysis of the ligand-binding domain of the Pseudomonas putida chemoreceptor McpS in complex with malate and succinate

    International Nuclear Information System (INIS)

    The crystallization of the ligand-binding domain of the methyl-accepting chemotaxis protein chemoreceptor McpS (McpS-LBD) is reported. Methyl-accepting chemotaxis proteins (MCPs) are transmembrane proteins that sense changes in environmental signals, generating a chemotactic response and regulating other cellular processes. MCPs are composed of two main domains: a ligand-binding domain (LBD) and a cytosolic signalling domain (CSD). Here, the crystallization of the LBD of the chemoreceptor McpS (McpS-LBD) is reported. McpS-LBD is responsible for sensing most of the TCA-cycle intermediates in the soil bacterium Pseudomonas putida KT2440. McpS-LBD was expressed, purified and crystallized in complex with two of its natural ligands (malate and succinate). Crystals were obtained by both the counter-diffusion and the hanging-drop vapour-diffusion techniques after pre-incubation of McpS-LBD with the ligands. The crystals were isomorphous and belonged to space group C2, with two molecules per asymmetric unit. Diffraction data were collected at the ESRF synchrotron X-ray source to resolutions of 1.8 and 1.9 Å for the malate and succinate complexes, respectively

  20. The human MCP-3 gene (SCYA7): Cloning, sequence analysis, and assignment to the C-C chemokine gene cluster on chromosome 17q11. 2-q12

    Energy Technology Data Exchange (ETDEWEB)

    Opdenakker, G.; Fiten, P.; Nys, G.; Froyen, G.; Van Damme, J. (Univ. of Leuven (Belgium)); Van Roy, N.; Speleman, F.; Laureys, G. (Univ. of Ghent (Belgium))

    1994-05-15

    Monocyte chemotactic proteins (MCPs) are chemokines involved in macrophage recruitment during inflammation and cancer. A full-size MCP-3 cDNA was used to isolate the functional human MCP-3 gene. Based on restriction analysis, subclones were selected and the MCP-3 gene sequence was completed. In addition to a dense region with direct and inverted repeats and palindromic sequences, a double microsatellite (CA)[sub n]-(GA)[sub n] was found at the 5[prime]-end of the MCP-3 gene, and an RFLP was detected. The gene was regionally mapped by fluorescence in situ hybridization to human chromosome 17, subbands q11.2-q12. This site contains the MCP-subset of C-C chemokines and can be distinguished from the syntenic MIP-1[alpha] locus. SCYA7 was assigned as the locus symbol of the MCP-3 gene. Double-labeling experiments confirmed the regional assignment of the MCP-3 gene close to the ERBB2 locus on human chromosome 17. 36 refs., 4 figs.

  1. Scattering and absorption coefficients of silica-doped alumina aerogels.

    Science.gov (United States)

    Fu, Tairan; Tang, Jiaqi; Chen, Kai; Zhang, Fan

    2016-02-01

    Alumina-based aerogels are especially useful in many applications due to their excellent stability at high temperatures. This study experimentally analyzed the radiative properties of silica-doped alumina aerogels through spectral directional-hemispherical measurements for wavelengths of 0.38-25 μm. The silica-doped alumina aerogel samples were prepared with a 1.4∶1 molar ratio of silica to alumina. A two-flux model was used to describe the radiation propagation in a 1D scattering absorbing sample to derive expressions for the normal-hemispherical transmittances and reflectances based on the transport approximation. The normal-hemispherical transmittances and reflectances were measured at various spectral wavelengths and sample thicknesses using the integrating sphere method. The spectral absorption and transport scattering coefficients of silica-doped alumina aerogels were then determined from the measured normal-hemispherical data. The absorption and transport scattering coefficients of silica-doped alumina aerogels are (0.1  cm-1, 36  cm-1) and (0.1  cm-1, 112  cm-1) for wavelengths of 0.38-8.0 μm. The spectral transport scattering coefficient varies in the opposite direction from the spectral absorption coefficient for various wavelengths. The radiative properties for silica and alumina aerogels were quite different for the absorption coefficient for wavelengths of 2.5-8.0 μm and for the transport scattering coefficient for wavelengths of 0.38-2.5 and 3.5-6.0 μm. The measured radiative properties were used to predict the spectral normal-hemispherical reflectance and transmittance of the silica-doped alumina aerogels for various sample thicknesses and wavelengths. The predicted values do not change for the sample thicknesses greater than a critical value. The analysis provides valuable reference data for alumina aerogels for high-temperature applications. PMID:26836071

  2. Ballistic Performance of Alumina and Zirconia-toughened Alumina Against 7.62 Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    S G. Savio

    2014-09-01

    Full Text Available A study was carried out to compare the ballistic performance of high purity alumina and zirconia-toughened alumina (ZTA using depth of penetration (DoP test configuration against 7.62 mm armour piercing (AP ammunition. The effect of tile thickness on the differential efficiency factor (DEF was studied for tile thickness in the range of 3 mm to 6 mm for alumina tiles and 3 mm to 5 mm for ZTA tiles. The DEF is found to increase as tile thickness increases. An analysis on the failed shots showed that the residual shot weight does not follow a single linear relationship with ceramic tile thickness unlike the residual DoP for all thicknesses of tiles. Post-ballistic analysis on ceramic powder for particle size distribution was carried out and the results are presented.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.477-483, DOI:http://dx.doi.org/10.14429/dsj.64.6745

  3. Mechanical behavior of alumina and alumina-feldspar based ceramics in an acetic acid (4%) environment

    International Nuclear Information System (INIS)

    This study investigates the mechanical properties of alumina-feldspar based ceramics when exposed to an aggressive environment (acetic acid 4%). Alumina ceramics containing different concentrations of feldspar (0%, 1%, 5%, 10%, or 40%) were sintered at either 1300, 1600, or 1700 oC. Flaws (of width 0%, 30%, or 50%) were introduced into the specimens using a saw. Half of these ceramic bodies were exposed to acetic acid. Their flexural strength, KIC, and porosity were measured and the fractured samples were evaluated using scanning electronic- and optical microscopy. It was found that in the ceramic bodies sintered at 1600 oC, feldspar content up to 10% improved flexural strength and KIC, and reduced porosities. Generally, it was found that acetic acid had a weakening effect on the flexural strength of samples sintered at 1700 oC but a beneficial effect on KIC of ceramics sintered at 1600 oC. It was concluded that alumina-based ceramics with feldspar content up to 10% and sintered at higher temperatures would perform better in an aggressive environment similar to oral cavity.

  4. Ação do 1-metilciclopropeno (1-MCP na vida de prateleira da banana 'maçã' Action of 1-methylcyclopropene (1-MCP on shelf life of 'apple' banana

    Directory of Open Access Journals (Sweden)

    Ana Carla Marques Pinheiro

    2005-04-01

    Full Text Available Objetivou-se avaliar o efeito do 1-metilciclopropeno (1-MCP, em diferentes concentrações, sobre a vida pós-colheita e sob as variáveis associadas aos atributos de qualidade de banana 'Maçã'. Frutos verde-maturos foram submetidos a cinco concentrações de 1-MCP (0; 50; 100; 150 e 200 etaL.L-1, por 12 horas, e foram analisados durante o amadurecimento sob condição ambiente (20±1ºC e 80±5% UR. O tratamento com 50 etaL.L-1 de 1-MCP atrasou o início do amadurecimento das bananas em aproximadamente 8 dias, baseando-se nas primeiras mudanças de coloração da casca, enquanto os tratamentos 100; 150 e 200 etaL.L-1 atrasaram-no em aproximadamente 10 dias. Observou-se, durante o amadurecimento, o amaciamento dos frutos, associado à conversão de amido em açúcares e ao aumento na solubilização péctica e na atividade da pectinametilesterase (PME e poligalacturonase (PG. A aplicação de 50 etaL.L-1de 1-MCP é a mais adequada por promover a extensão da vida de prateleira de bananas 'Maçã', preservando sua qualidade com base nas análises de açúcares solúveis totais, pectinas total e solúvel, firmeza e aparência externa ao final do armazenamento.The objective of this work was to evaluate the influence of the 1-MCP, at different concentrations, on quality and shelf life of 'Apple' banana. Green mature fruits were submitted to five concentrations of 1-MCP (0, 50, 100, 150 and 200 etaL.L-1, for 12 hours and analyzed during the ripening at room temperature (20ºC ± 1 and 80% ± 5 RH . The 1-MCP at 50 etaL.L-1 delayed, in 8 days, the begining of the ripening, based in the first changes of peel color, whereas 100, 150 and 200 etaL.L-1 treatments delayed the begining of the ripening in 10 days, in comparison to the control. The softening of the fruits, associated to the conversion of starch in sugar and the increasing in the pectic solubilization and activity of pectinmethylsterase and polygalacturonase, was observed during the ripening

  5. Resposta da aplicação do 1-MCP em frutos de mamoeiro 'Golden' em diferentes estádios de maturação Responses of 1-MCP applications in 'Golden' papaya fruits on differents maturation stages

    OpenAIRE

    Maximiliano Silva de Souza; Inga Gonçalves de Azevedo; Sávio Figueira Corrêa; Marcelo Gomes da Silva; Messias Gonzaga Pereira; Jurandi Gonçalves de Oliveira

    2009-01-01

    O estudo de fatores que influenciam no processo de amadurecimento é fundamental para o planejamento do processo de comercialização, principalmente em frutos com padrão de respiração climatérico e perecível, como é o caso do mamão. Nesse trabalho, avaliou-se o efeito da aplicação do 1-MCP (1-metilciclopropeno) sobre o amadurecimento de frutos de mamoeiro nos estádios 0; 1 e 2 de maturação. O 1-MCP diminui a produção de etileno (≈79%) e a taxa respiratória (≈45%), principalmente em ...

  6. Sheathless interface for coupling capillary electrophoresis with mass spectrometry

    Science.gov (United States)

    Wang, Chenchen; Tang, Keqi; Smith, Richard D.

    2014-06-17

    A sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry is disclosed. The sheathless interface includes a separation capillary for performing CE separation and an emitter capillary for electrospray ionization. A portion of the emitter capillary is porous or, alternatively, is coated to form an electrically conductive surface. A section of the emitter capillary is disposed within the separation capillary, forming a joint. A metal tube, containing a conductive liquid, encloses the joint.

  7. Diagnostics of a high current capillary discharge

    International Nuclear Information System (INIS)

    We have demonstrated that thin (10 to 25 μm diameter) capillaries can be fabricated in suitably configured insulators for use in pulse power machines. Large currents can be used to heat these capillaries which produce photons with an energies greater than 1 keV

  8. Pulmonary capillary haemangiomatosis in a premature infant

    International Nuclear Information System (INIS)

    Pulmonary capillary haemangiomatosis (PCH) is a rare disorder characterized by widespread capillary proliferation in the lung, infiltrating the interstitium and the alveolar walls. We present the HRCT features of PCH in a surviving ex-premature infant. To our knowledge, this is a unique case of the radiological features of PCH in a young living infant. (orig.)

  9. Pulmonary capillary haemangiomatosis in a premature infant

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cicero J.T.A.; Massie, John; Mandelstam, Simone A. [University of Melbourne, Royal Children' s Hospital, Parkville, VIC (Australia)

    2005-06-01

    Pulmonary capillary haemangiomatosis (PCH) is a rare disorder characterized by widespread capillary proliferation in the lung, infiltrating the interstitium and the alveolar walls. We present the HRCT features of PCH in a surviving ex-premature infant. To our knowledge, this is a unique case of the radiological features of PCH in a young living infant. (orig.)

  10. Aluminum matrix composites reinforced with alumina nanoparticles

    CERN Document Server

    Casati, Riccardo

    2016-01-01

    This book describes the latest efforts to develop aluminum nanocomposites with enhanced damping and mechanical properties and good workability. The nanocomposites exhibited high strength, improved damping behavior and good ductility, making them suitable for use as wires. Since the production of metal matrix nanocomposites by conventional melting processes is considered extremely problematic (because of the poor wettability of the nanoparticles), different powder metallurgy routes were investigated, including high-energy ball milling and unconventional compaction methods. Special attention was paid to the structural characterization at the micro- and nanoscale, as uniform nanoparticle dispersion in metal matrix is of prime importance. The aluminum nanocomposites displayed an ultrafine microstructure reinforced with alumina nanoparticles produced in situ or added ex situ. The physical, mechanical and functional characteristics of the materials produced were evaluated using different mechanical tests and micros...

  11. Crystallography of Alumina-YAG-Eutectic

    Science.gov (United States)

    Farmer, Serene C.; Sayir, Ali; Dickerson, Robert M.; Matson, Lawrence E.

    2000-01-01

    Multiple descriptions of the alumina-YAG eutectic crystallography appear in the ceramic literature. The orientation between two phases in a eutectic system has direct impact on residual stress, morphology, microstructural stability, and high temperature mechanical properties. A study to demonstrate that the different crystallographic relationships can be correlated with different growth constraints was undertaken. Fibers produced by Laser-Heated Float Zone (LHFZ) and Edge-defined Film-fed Growth (EFG) were examined. A map of the orientation relationship between Al2O3 and Y3Al5O12 and their relationship to the fiber growth axis as a function of pull rate are presented. Regions in which a single orientation predominates are identified.

  12. Fracture simulation for zirconia toughened alumina microstructure

    CERN Document Server

    Kim, Kyungmok; Forest, Bernard

    2013-01-01

    Purpose - The purpose of this paper is to describe finite element modelling for fracture and fatigue behaviour of zirconia toughened alumina microstructures. Design/methodology/approach - A two-dimensional finite element model is developed with an actual $Al{_2}O{_3}$ - 10 vol% $ZrO{_2}$ microstructure. A bilinear, time-independent cohesive zone law is implemented for describing fracture behaviour of grain boundaries. Simulation conditions are similar to those found at contact between a head and a cup of hip prosthesis. Residual stresses arisen from the mismatch of thermal coefficient between grains are determined. Then, effects of a micro-void and contact stress magnitude are investigated with models containing residual stresses. For the purpose of simulating fatigue behaviour, cyclic loadings are applied to the models. Findings - Results show that crack density is gradually increased with increasing magnitude of contact stress or number of fatigue cycles. It is also identified that a micro-void brings about...

  13. Cast alumina forming austenitic stainless steels

    Science.gov (United States)

    Muralidharan, Govindarajan; Yamamoto, Yukinori; Brady, Michael P

    2013-04-30

    An austenitic stainless steel alloy consisting essentially of, in terms of weight percent ranges 0.15-0.5C; 8-37Ni; 10-25Cr; 2.5-5Al; greater than 0.6, up to 2.5 total of at least one element selected from the group consisting of Nb and Ta; up to 3Mo; up to 3Co; up to 1W; up to 3Cu; up to 15Mn; up to 2Si; up to 0.15B; up to 0.05P; up to 1 total of at least one element selected from the group consisting of Y, La, Ce, Hf, and Zr; alumina, and a stable essentially single phase FCC austenitic matrix microstructure, the austenitic matrix being essentially delta-ferrite free and essentially BCC-phase-free. A method of making austenitic stainless steel alloys is also disclosed.

  14. Optimized alumina coagulants for water treatment

    Science.gov (United States)

    Nyman, May D.; Stewart, Thomas A.

    2012-02-21

    Substitution of a single Ga-atom or single Ge-atom (GaAl.sub.12 and GeAl.sub.12 respectively) into the center of an aluminum Keggin polycation (Al.sub.13) produces an optimal water-treatment product for neutralization and coagulation of anionic contaminants in water. GaAl.sub.12 consistently shows .about.1 order of magnitude increase in pathogen reduction, compared to Al.sub.13. At a concentration of 2 ppm, GaAl.sub.12 performs equivalently to 40 ppm alum, removing .about.90% of the dissolved organic material. The substituted GaAl.sub.12 product also offers extended shelf-life and consistent performance. We also synthesized a related polyaluminum chloride compound made of pre-hydrolyzed dissolved alumina clusters of [GaO.sub.4Al.sub.12(OH).sub.24(H.sub.2O).sub.12].sup.7+.

  15. Low power readout electronics for a UV MCP detector with cross strip anode

    International Nuclear Information System (INIS)

    After the shutdown of the Hubble Space Telescope in a few years, new astronomical missions for the ultraviolet (UV) wavelength range between 91 and 300 nm with improved optics and detectors will be necessary. This fact drives our development of solar blind photon counting microchannel plate (MCP) UV detectors with high quantum efficiency, high spatial resolution, and low power readout electronics. We plan to use a cross-strip anode (XSA), which has a high spatial resolution and additionally allows a low gain operation of the MCPs which leads to an increased lifetime of the MCPs compared to detectors with other anode types. The main difficulty in implementing an XSA in a detector for space applications is the need for a (pre-) amplifier, a shaper, and an ADC for each of the strips, which means large power consumption and spatial requirements. The solution we are studying is the application of the so-called Beetle chip. This allows for an implementation of a readout electronics for an XSA with a power consumption of less then 10 W. For the tests of our readout electronics prototype, and for the burn-in of the MCPs, we recently finished a setup in a vacuum chamber that is similar to the configuration in the final detector. We present a brief overview of our detector design and details of the readout electronics setup as well as details of the setup in our vacuum chamber

  16. An Internal ALD-Based High Voltage Divider and Signal Circuit for MCP-based Photodetectors

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bernhard W.; Elagin, Andrey; Elam, Jeffrey W.; Frisch, Henry J.; Genat, Jean-Francois; Gregar, Joseph S.; Mane, Anil U.; Minot, Michael J.; Northrup, Richard; Obaid, Razib; Oberla, Eric; Alexander, Vostrikov; Wetstein, Matthew

    2015-04-21

    We describe a pin-less design for the high voltage (HV) resistive divider of the all-glass LAPPD (TM) 8 in,square thin photodetector module. The divider, which distributes high voltage applied to the photocathode to the two micro-channel plates (MCPs) that constitute the amplification stage, is comprised of the two MCPs and three glass mechanical spacers, each of which is coated with a resistive layer using atomic layer deposition (ALD). The three glass grid spacers and the two MCPs form a continuous resistive path between cathode and anode, with the voltages across the MCPs and the spacers determined by the resistance of each. High voltage is applied on an external tab on the top glass window that connects to the photocathode through the metal seal. The DC ground is supplied by microstrips on the bottom glass plate that form the high-bandwidth anode. The microstrips exit the package through the glass-frit seal of the anode base-plate and the package sidewall. The divider is thus completely internal, with no HV pins penetrating the low-profile flat glass package. Measurements of the performance of the divider are presented for the 8 in.-square MCP and spacer package in a custom test fixture and for an assembled externally pumped LAPPD (TM) prototype with an aluminum photocathode. (C) 2015 Elsevier B.V. All rights reserved.

  17. An internal ALD-based high voltage divider and signal circuit for MCP-based photodetectors

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bernhard W. [Argonne National Laboratory (United States); Elagin, Andrey [Enrico Fermi Institute, University of Chicago (United States); Elam, Jeffrey W. [Argonne National Laboratory (United States); Frisch, Henry J., E-mail: frisch@hep.uchicago.edu [Enrico Fermi Institute, University of Chicago (United States); Genat, Jean-Francois [Enrico Fermi Institute, University of Chicago (United States); Gregar, Joseph S.; Mane, Anil U. [Argonne National Laboratory (United States); Minot, Michael J. [Minotech Engineering, Inc and Incom, Inc (United States); Northrop, Richard; Obaid, Razib; Oberla, Eric; Vostrikov, Alexander; Wetstein, Matthew [Enrico Fermi Institute, University of Chicago (United States)

    2015-04-21

    We describe a pin-less design for the high voltage (HV) resistive divider of the all-glass LAPPD{sup TM} 8 in.-square thin photodetector module. The divider, which distributes high voltage applied to the photocathode to the two micro-channel plates (MCPs) that constitute the amplification stage, is comprised of the two MCPs and three glass mechanical spacers, each of which is coated with a resistive layer using atomic layer deposition (ALD). The three glass grid spacers and the two MCPs form a continuous resistive path between cathode and anode, with the voltages across the MCPs and the spacers determined by the resistance of each. High voltage is applied on an external tab on the top glass window that connects to the photocathode through the metal seal. The DC ground is supplied by microstrips on the bottom glass plate that form the high-bandwidth anode. The microstrips exit the package through the glass-frit seal of the anode base-plate and the package sidewall. The divider is thus completely internal, with no HV pins penetrating the low-profile flat glass package. Measurements of the performance of the divider are presented for the 8 in.-square MCP and spacer package in a custom test fixture and for an assembled externally pumped LAPPD{sup TM} prototype with an aluminum photocathode.

  18. Low power readout electronics for a UV MCP detector with cross strip anode

    Science.gov (United States)

    Pfeifer, M.; Diebold, S.; Barnstedt, J.; Hermanutz, S.; Kalkuhl, C.; Kappelmann, N.; Schanz, T.; Werner, K.

    2014-03-01

    After the shutdown of the Hubble Space Telescope in a few years, new astronomical missions for the ultraviolet (UV) wavelength range between 91 and 300 nm with improved optics and detectors will be necessary. This fact drives our development of solar blind photon counting microchannel plate (MCP) UV detectors with high quantum efficiency, high spatial resolution, and low power readout electronics. We plan to use a cross-strip anode (XSA), which has a high spatial resolution and additionally allows a low gain operation of the MCPs which leads to an increased lifetime of the MCPs compared to detectors with other anode types. The main difficulty in implementing an XSA in a detector for space applications is the need for a (pre-) amplifier, a shaper, and an ADC for each of the strips, which means large power consumption and spatial requirements. The solution we are studying is the application of the so-called Beetle chip. This allows for an implementation of a readout electronics for an XSA with a power consumption of less then 10 W. For the tests of our readout electronics prototype, and for the burn-in of the MCPs, we recently finished a setup in a vacuum chamber that is similar to the configuration in the final detector. We present a brief overview of our detector design and details of the readout electronics setup as well as details of the setup in our vacuum chamber.

  19. Sector Multipad Prototype of the FMD-MCP Detector for ALICE (1997)

    CERN Document Server

    Antropov, A E; Feofilov, G A; Izrailov, E K; Kasatkin, V A; Klempt, W; Kolojvari, A A; Larin, M P; Lazarev, V A; Novikov, I A; Potapov, S V; Stolyarov, O I; Tsimbal, F A; Tulina, T A; Valiev, F F; Vinogradov, L I

    1997-01-01

    We present results of the technology, manufacturing andfirst tests of a novel MCP-based sector prototypefor the Forward Multiplicity Detector for the ALICE experiment at the LHC. The detector is to provide better than sqrt(M)/Mresolution for high multiplicity events, and about 50 pstiming resolution. Two Sector MCPs are mounted on a 200 ceramics board with the multipad readout integrated with a passive summator. This microelectronics UHF device provides isochronous analogue summation of the fast 1ns signal components from 8 pads, along with the individual readout of charges. The setup is baked under 300C and then sealedinto a singular thin wall (200 ) stainlesssteel vacuum sector chamber with Ti getter keeping a vacuum of 10-5Torr.The separation of the fast and slow componentsallows us to use this detector as the zero level trigger,in pile up and beam-gas interaction diagnostics and for thedetermination of the collision vertex along the beam axis. The results of the first and future lab and in-beam tests are ...

  20. An internal ALD-based high voltage divider and signal circuit for MCP-based photodetectors

    International Nuclear Information System (INIS)

    We describe a pin-less design for the high voltage (HV) resistive divider of the all-glass LAPPDTM 8 in.-square thin photodetector module. The divider, which distributes high voltage applied to the photocathode to the two micro-channel plates (MCPs) that constitute the amplification stage, is comprised of the two MCPs and three glass mechanical spacers, each of which is coated with a resistive layer using atomic layer deposition (ALD). The three glass grid spacers and the two MCPs form a continuous resistive path between cathode and anode, with the voltages across the MCPs and the spacers determined by the resistance of each. High voltage is applied on an external tab on the top glass window that connects to the photocathode through the metal seal. The DC ground is supplied by microstrips on the bottom glass plate that form the high-bandwidth anode. The microstrips exit the package through the glass-frit seal of the anode base-plate and the package sidewall. The divider is thus completely internal, with no HV pins penetrating the low-profile flat glass package. Measurements of the performance of the divider are presented for the 8 in.-square MCP and spacer package in a custom test fixture and for an assembled externally pumped LAPPDTM prototype with an aluminum photocathode

  1. The MCP Altona incident: the Canadian regulatory response and framework for the export of uranium

    International Nuclear Information System (INIS)

    On 23 December 2010, a cargo ship carrying 350 000 kilograms (kg) of uranium ore concentrates (U3O8) belonging to the Canadian resource corporation Cameco left Vancouver, British Columbia, Canada and encountered severe weather conditions between Hawaii and the Midway Islands in international waters en route to Zhanjiang, People's Republic of China (PRC). The ship, the MCP Altona, suffered some damage to its hull but was able to continue to operate through the storm. Once the sea had calmed, the crew noticed that some of the containers on the ship had shifted and had been damaged. The captain, however, was unable to secure the necessary authorizations to obtain safe harbour in the area as there were no signs of immediate risk to the health and safety of the ship's crew. On Cameco's recommendation, the ship returned to British Columbia. This article describes the response of the Canadian Nuclear Safety Commission (CNSC) to this incident. The article also discusses the Canadian policy and regulatory framework for controls on the export of uranium

  2. Processing of silicon nitride and alumina nanosize powders

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, E.J.; Piermarini, G.; Hockey, B.; Malghan, S.G. [National Inst. of Standard and Technology, Gaithersburg, MD (United States)

    1995-08-01

    The effects of pressure on the compaction and subsequent processing of nanosize {gamma} alumina powders were studied. A 3 mm diameter piston/cylinder die was used to compact the nanosize powders to pressures of 1 and 2.5 GPa. The green bodies were sintered at temperatures up to 1600{degrees}C. Results show that green body density can be increased by higher compaction pressures. It appears that as a result of the {gamma}-to-{alpha} transformation in alumina, higher green density does not necessarily produce a higher density sintered alumina body. The microstructures of the sintered bodies are described in terms of porosity and phase content.

  3. Reaction of Sillimnite with Alumina at Elevated Temperatures

    Institute of Scientific and Technical Information of China (English)

    SHENYang-yun; SHENYi

    1996-01-01

    The reaction of sillimanite with alumina at temperatures 1650℃ an 1750℃ has been investigated.The results have shown that,in the laboratory test conditions,the higher the alumina content,the lower will be the amounts of glass-phse of the fired body and the higher will be the formation of mullite .In the present tests,however,the reaction in concern has not been completed,the reaction in concern has not been completed.Some uncombined residual alumina still exist in the form of corundum.

  4. Blister formation in alumina thin films bombarded with xenon ions

    International Nuclear Information System (INIS)

    Blisters have been observed in evaporated alumina thin films after xenon irradiation. The aim of this study is to further understand the mechanisms responsible for such a process. Surface blistering dependence on the thickness of the alumina films as well as irradiation fluence, temperature and post-irradiation thermal annealing have been investigated. From our experimental results, it has been proved that the substrate-alumina interface is not responsible for blistering. The application of a gas pressure model and a lateral compressive stress model shows that the latter seems to be more adequate in explaining blister formation. (author)

  5. Wenshan’s 800,000-ton Alumina Project Completed

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>On September 26,2012,the completion ceremony of the 800,000-ton alumina project was held at the alumina factory in Matang Industrial Park, Wenshan city,Yunnan.Wenshan’s 800,000-ton alumina project and its supporting mining construction projects have been listed as one of 20 major industrial construction projects of Yunnan. The project covers an area of approximately 5,500 mu,with an estimated total investment of RMB 4,987 million. It is invested and built

  6. 3.6. Chlorination of alumina containing waste products

    International Nuclear Information System (INIS)

    Chlorination of alumina containing waste products is considered in this article. Based on conducted studies following optimal conditions of chlorination of alumina containing waste products with reducer - coal were found: temperature - 750-850 deg C, chlorination duration -1-1,5 hours, quantity of reducer - 30% and size of particles - 0,1 mm. Based on conducted studies following optimal conditions of chlorination of alumina containing waste products with reducer - natural gas were found: temperature - 650-750 deg C, chlorination duration - 2 hours, chlorine to methane ratio is 4:1 and size of particles - 0,2-0,3 mm.

  7. Porous alumina based ordered nanocomposite coating for wear resistance

    Science.gov (United States)

    Yadav, Arti; Muthukumar, M.; Bobji, M. S.

    2016-08-01

    Uniformly dispersed nanocomposite coating of aligned metallic nanowires in a matrix of amorphous alumina is fabricated by pulsed electrodeposition of copper into the pores of porous anodic alumina. Uniform deposition is obtained by controlling the geometry of the dendritic structure at the bottom of pores through stepwise voltage reduction followed by mild etching. The tribological behaviour of this nanocomposite coating is evaluated using a ball on flat reciprocating tribometer under the dry contact conditions. The nanocomposite coating has higher wear resistance compared to corresponding porous alumina coating. Wear resistant nanocomposite coating has wide applications especially in protecting the internal surfaces of aluminium internal combustion engines.

  8. Alumina Paste Sublimation Suppression Barrier for Thermoelectric Device

    Science.gov (United States)

    Paik, Jong-Ah (Inventor); Caillat, Thierry (Inventor)

    2014-01-01

    Alumina as a sublimation suppression barrier for a Zintl thermoelectric material in a thermoelectric power generation device operating at high temperature, e.g. at or above 1000K, is disclosed. The Zintl thermoelectric material may comprise Yb.sub.14MnSb.sub.11. The alumina may be applied as an adhesive paste dried and cured on a substantially oxide free surface of the Zintl thermoelectric material and polished to a final thickness. The sublimation suppression barrier may be finalized by baking out the alumina layer on the Zintl thermoelectric material until it becomes substantially clogged with ytterbia.

  9. Characterization of Glasses in One Type of Alumina Rich Fly Ash by Chemical Digestion Methods: Implications for Alumina Extraction

    Directory of Open Access Journals (Sweden)

    Lijun Zhao

    2016-01-01

    Full Text Available In recent years, one type of alumina rich fly ash (ARFA with about 50 wt% of alumina has been extensively investigated for alumina extraction in China. Due to the silica in ARFA, alumina extraction would have to generate a huge amount of solid waste. There is a growing interest in the glasses in ARFA, because they are composed mainly of silica and could be removed prior to alumina extraction. In this work, the glasses in ARFA have been investigated by chemical methods, that is, acid and base digestions. The chemical compositions have been measured by XRF for ARFA from the digestion processes. The K2O standard, XRD, and FTIR spectroscopies were successfully used to define the digestions processes, and size analysis and SEM-EDX provided rich information on particle transformations. As a result, acid and base digestion methods were found to produce very similar results for the glasses in ARFA. The K2O standard was attributed to the formation of glasses by illites, and TiO2 and Fe2O3 were proposed to originate from ilmenite in alumina rich coals (ARC. Some implications of the results were also discussed for the alumina extraction from ARFA.

  10. Effect of One-methylcyclopropene (1-MCP) and chlorine dioxide (ClO2) on preservation of green walnut fruit and kernel traits.

    Science.gov (United States)

    Jiang, Liuqing; Feng, Wenyu; Li, Fang; Xu, Jingying; Ma, Yanping; Ma, Huiling

    2015-01-01

    The effect of the ethylene receptor competitor 1-methylcyclopropene (1-MCP) and the legally approved disinfectant chlorine dioxide (ClO2) on preservation of the green walnut fruit during storage was investigated. Green Chinese walnut fruit cv. Xilin No.2 was harvested on commercial maturity and stored at 0-1 °C after the fruit was treated by water (control), 80 mg L(-1)ClO2 (ClO2), 0.5 μL L(-1)1-MCP (1-MCP), or combination treatment of 80 mg L(-1) ClO2 with either 0.1 μL L(-1) 1-MCP (0.1 1-MCP+ ClO2) or 0.5 μL L(-1) 1-MCP (0.5 1-MCP+ ClO2). During storage, respiration, ethylene production, phenolics content, antioxidative activity, weight changes, decay of the fruit and kernel traits of acid value, peroxide value,free fatty were measured. All treatments decreased postharvest respiration intensity in different degrees and inhibited ethylene production peak. ClO2 increased the total phenol and flavonoid content of the green fruit compared with other treatments and the control (P treatment. After 42-day storage, ClO2 remained higher fresh weight and lower decay index than control, while 1-MCP increased the fruit decay index. Final acid values of kernel from ClO2, control and 0.1 1-MCP+ ClO2 were not different from their initial values, which from 0.5 1-MCP increased. Final peroxide value for kernel from ClO2 showed no change during storage but increased at least 1.0-fold for other treatments. ClO2 preserved 99.9 % of initial free fatty acid, similar to that for the control (99.8 %), whereas 0.5 1-MCP preserved only 95.7 %. ClO2 is of potential in decay retardation and kernel traits maintenance of green walnut fruit, whereas the 1-MCP has a negative effect for decay control on walnut. PMID:25593369

  11. Qualidade pós-colheita de quivi 'Hayward' tratado com 1-MCP e armazenado sob diferentes atmosferas

    Directory of Open Access Journals (Sweden)

    Marcelo José Vieira

    2012-06-01

    Full Text Available Este trabalho teve por objetivo avaliar o efeito do 1-MCP sobre o amadurecimento e a qualidade pós-colheita de quivi 'Hayward' armazenado sob diferentes atmosferas. Foram conduzidos dois experimentos, com frutos colhidos em pomar comercial localizado em Fraiburgo-SC. No experimento 1, os frutos foram tratados com três doses de 1-MCP (0,0; 0,5 ou 1,0 µL L-1 e armazenados sob atmosfera controlada (AC, contendo 2,0kPa de O2 + 4,5kPa de CO2, a 0ºC ± 0,5ºC, 92 ± 3% UR, e com <40 ηL L-1 de etileno no ambiente, durante 90 e 120 dias, mais sete dias de vida de prateleira a 23ºC. No experimento 2, os frutos foram tratados com 0,0 ou 0,7 µL L-1 de 1-MCP e armazenados sob atmosfera ambiente (AA, contendo 21 kPa de O2 + 0,03 kPa de CO2, a 0 ± 0,5ºC, 90 ± 3% UR, e com 200 a 250 ηL L-1 de etileno no ambiente, durante 30, 60, 90 e 120 dias, mais um e sete dias de vida de prateleira a 23ºC ou AC (contendo 2,0 kPa de O2 + 4,5 kPa de CO2, a 0ºC ± 0,5ºC, 92 ± 3% UR, e com <40 ηL L-1 de etileno no ambiente, durante 60, 90, 120 e 150 dias, mais um e sete dias de vida de prateleira a 23ºC. Os benefícios do tratamento com 1-MCP sobre a conservação da qualidade foram observados tanto para frutos armazenados sob AA quanto sob AC. No experimento 1, não houve diferença entre as doses de 1-MCP de 0,5 e 1,0 µL L-1 sobre o controle do amadurecimento e manutenção da qualidade dos frutos armazenados em AC. No experimento 2, o tratamento com 1-MCP retardou o aumento na taxa de produção de etileno após remoção de câmara fria. A redução da taxa de produção de etileno nos frutos tratados com 1-MCP foi associada ao aumento na conservação da firmeza da polpa sob AC e AA, e redução na incidência de pericarpo translúcido sob AA. O potencial de armazenamento foi aumentado pelo tratamento com 1-MCP em aproximadamente 60 e 30 dias, nos frutos armazenados sob AA e AC, respectivamente.

  12. MCP2036:电感式触摸传感模拟前端器件(AFE)

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Microchip近日推出针对电感式触摸传感应用的MCP2036模拟前端器件(AFE)。全集成的MCP2036 AFE几乎可以与任何8位、16位及32位PIC单片机(MCU)或dsPIC数字信号控制器(DSC)配合使用,进一步充实了Microchip免版税mTouch电感式触摸传感解决方案,有助于设计人员更简便、更具成本效益地利用电感式触摸传感技术加强用户界面功能。

  13. Development and testing of cost-effective, 6 cm x 6 cm MCP-based photodetectors for fast timing applications

    CERN Document Server

    Wang, Jingbo; Demarteau, Marcel; Elam, Jeffrey; Mane, Anil; May, Edward; Wagner, Robert; Walters, Dean; Xie, Junqi; Xia, Lei; Zhao, Huyue

    2016-01-01

    Micro-channel plate (MCP)-based photodetectors are capable of picosecond level time resolution and sub-mm level position resolution, which makes them a perfect candidate for the next generation large area photodetectors. The large-area picosecond photodetector (LAPPD) collaboration is developing new techniques for making large-area photodetectors based on new MCP fabrication and functionalization methods. A small single tube processing system (SmSTPS) was constructed at Argonne National Laboratory (ANL) for developing scalable, cost-effective, glass-body, 6 cm x 6 cm, picosecond photodetectors based on MCPs functionalized by Atomic Layer Deposition (ALD). Recently, a number of fully processed and hermitically sealed prototypes made of MCPs with 20 micron pores have been fabricated. This is a significant milestone for the LAPPD project. These prototypes were characterized with a pulsed laser test facility. Without optimization, the prototypes have shown excellent results: The time resolution is ~57 ps for sing...

  14. Mlp24 (McpX) of Vibrio cholerae Implicated in Pathogenicity Functions as a Chemoreceptor for Multiple Amino Acids

    OpenAIRE

    Nishiyama, So-ichiro; Suzuki, Daisuke; Itoh, Yasuaki; Suzuki, Kazuho; Tajima, Hirotaka; Hyakutake, Akihiro; Homma, Michio; Butler-Wu, Susan M.; Camilli, Andrew; Kawagishi, Ikuro

    2012-01-01

    The chemotaxis of Vibrio cholerae, the causative agent of cholera, has been implicated in pathogenicity. The bacterium has more than 40 genes for methyl-accepting chemotaxis protein (MCP)-like proteins (MLPs). In this study, we found that glycine and at least 18 l-amino acids, including serine, arginine, asparagine, and proline, serve as attractants to the classical biotype strain O395N1. Based on the sequence comparison with Vibrio parahaemolyticus, we speculated that at least 17 MLPs of V. ...

  15. Association of MCP-1-2518A/G polymorphism with susceptibility to autoimmune diseases: a meta-analysis.

    Science.gov (United States)

    Chen, Si; Deng, Chuiwen; Hu, Chaojun; Li, Jing; Wen, Xiaoting; Wu, Ziyan; Li, Yuan; Zhang, Fengchun; Li, Yongzhe

    2016-05-01

    We performed a meta-analysis to estimate whether combined evidence shows the association between the MCP-1-2518A/G polymorphism and susceptibility to autoimmune diseases. Relevant articles dated to July 2014 were acquired from the PubMed, EMBASE, ISI, and CNKI databases. The number of the genotypes and/or alleles for the MCP-1-2518A/G in cases and control subjects was extracted, and statistical analysis was conducted using STATA 11.2 software. Summary odds ratios (ORs) with their 95 % confidence intervals (95 % CIs) were used to calculate the risk of autoimmune diseases with the MCP-1-2518A/G. Significant increased risk of autoimmune diseases could be found for A allele vs. G allele (OR = 1.616, 95 % CI 1.027-2.542, P = 0.038) and AA + AG vs. GG (OR = 1.616, 95 % CI 1.027-2.542, P = 0.038) in Asian patients with rheumatoid arthritis (RA), and for A allele vs. G allele (OR = 1.383, 95 % CI 1.142-1.676, P = 0.022) and AA vs. AG + GG (OR = 1.575, 95 % CI 1.361-1.823, P < 0.001) in European patients with Crohn's disease (CD). In addition, when comparison of European patients with lupus nephritis (LN) and without LN, significant association between patients with LN and without LN also could be found for AA vs. AG + GG (OR = 0.713, 95 % CI 0.545-0.933, P = 0.014). This meta-analysis showed that the MCP-1-2518-A allele confers susceptibility to Asian patients with RA and European patients with CD. PMID:26318885

  16. Aumento da expressão do MCP-1 coroidal e escleral em modelo experimental de hipercolesterolemia

    Directory of Open Access Journals (Sweden)

    Rogil José de Almeida Torres

    2012-02-01

    Full Text Available OBJETIVO: O objetivo deste trabalho é demonstrar experimentalmente que a dieta rica em colesterol provoca aumento da expressão da MCP-1 na coroide e esclera. MÉTODO: Coelhos New Zealand foram organizados em dois grupos: GN (grupo dieta normal, composto por 8 coelhos (8 olhos, recebeu ração padrão para coelhos, durante 4 semanas; GH (grupo hipercolesterolêmico, composto por 13 coelhos (13 olhos, recebeu dieta rica em colesterol a 1% por 8 semanas. Foi realizada a dosagem sérica de colesterol total, triglicerídeos, HDL colesterol, glicemia de jejum no início do experimento e no momento da eutanásia. Ao final da 8ª semana para o GH e 4ª semana para o GN foi realizada a eutanásia dos animais e os olhos foram submetidos à análise imuno-histoquímica com o anticorpo anti-MCP-1. RESULTADOS: A dieta provocou significativo aumento do colesterol total e triglicerídeos do GH em relação ao GN (p<0,001. Houve significativo aumento da expressão da MCP-1 na coroide e esclera dos animais do GH em relação ao GN (p<0,001. CONCLUSÃO: Este estudo demonstrou que a dieta hipercolesterolêmica em coelhos induz ao aumento da expressão do MCP-1 na coroide e esclera.

  17. Capillary Discharge XUV Radiation Source

    Directory of Open Access Journals (Sweden)

    M. Nevrkla

    2009-01-01

    Full Text Available A device producing Z-pinching plasma as a source of XUV radiation is described. Here a ceramic capacitor bank pulse-charged up to 100 kV is discharged through a pre-ionized gas-filled ceramic tube 3.2 mm in diameter and 21 cm in length. The discharge current has amplitude of 20 kA and a rise-time of 65 ns. The apparatus will serve as experimental device for studying of capillary discharge plasma, for testing X-ray optics elements and for investigating the interaction of water-window radiation with biological samples. After optimization it will be able to produce 46.9 nm laser radiation with collision pumped Ne-like argon ions active medium. 

  18. Investigations of the MCP Detector of a Time-Of-Flight Detector for IMS at the FRS-ESR

    International Nuclear Information System (INIS)

    The Isochronous Mass Spectrometry at the FRS-ESR facility at GSI can be used to perform high-precision mass measurements of exotic nuclei. The mass values are obtained from measuring the revolution time of the ions in the storage ring with a time-of-flight detector. The ions pass a thin carbon foil in the detector and release secondary electrons. These electrons are guided by electric and magnetic fields to two MCP detectors. Their number is amplified by micro channel plates and the resulting current is detected by an anode. In order to achieve an accurate time signal, the timing performance of the MCP detector is very important. The timing performance and the signal shape of the detector setup has been improved by including a new anode design. At the same time, the detector performance dependence on the magnetic field and the electron velocity inside of the MCP-detector was tested. The new detector design and the test results are presented.

  19. Direct spray pyrolysis of aluminum chloride solution for alumina preparation

    Institute of Scientific and Technical Information of China (English)

    吕国志; 张廷安; 王龙; 马思达; 豆志河; 刘燕

    2014-01-01

    The effects of pyrolysis mode and pyrolysis parameters on Cl content in alumina were investigated, and the alumina products were characterized by XRD, SEM and ASAP. The experimental results indicate that the spray pyrolysis efficiency is higher than that of static pyrolysis process, and the reaction and evaporation process lead to a multi-plot state of the alumina products by spray pyrolysis. Aluminum phase starts to transform intoγ-Al2O3 at spray pyrolysis temperature of 600 °C, which is about 200 °C lower than that of static pyrolysis process. The primary particle size of γ-Al2O3 product is 27.62 nm, and Cl content in alumina products is 0.38%at 800 °C for 20 min.

  20. Structure and surface properties of praseodymium modified alumina

    International Nuclear Information System (INIS)

    Mixed PrO2-Al2O3 oxides with different PrO2 content (1-20 wt.%) were prepared by wetness impregnation of γ-alumina with aqueous solution of praseodymium nitrate. The samples were characterized by different techniques, using surface adsorption-desorption of N2 (SBET), thermogravimetric analysis (TGA), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), temperature-programmed reduction (TPR) and temperature-programmed desorption of CO2 (TPD-CO2). TGA and XRD showed the presence of small praseodymium oxide species on the alumina surface. XPS and DRS detected electron deficient interaction between deposited praseodymium oxide and alumina. It was observed a lower reduction temperature for supported Pr oxide species compared to that of the bulk Pr6O11. TPD-CO2 studies suggested that the deposition of Pr oxide on alumina leaded to increase of the basicity of mixed oxides.

  1. Fused Cast Alumina Refractory Products for Glass Tank Furnace

    Institute of Scientific and Technical Information of China (English)

    SHEN Keyin

    2006-01-01

    @@ 1 Subject and Scope The standard specifies the requirement, testing method, inspection rule and requirements for the labeling, packing, shipping and storing of the fused cast alumina refractory products for glass tanks.

  2. Aluminum microstructures on anodic alumina for aluminum wiring boards.

    Science.gov (United States)

    Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki

    2010-03-01

    The paper demonstrates simple methods for the fabrication of aluminum microstructures on the anodic oxide film of aluminum. The aluminum sheets were first engraved (patterned) either by laser beam or by embossing to form deep grooves on the surface. One side of the sheet was then anodized, blocking the other side by using polymer mask to form the anodic alumina. Because of the lower thickness at the bottom part of the grooves, the part was completely anodized before the complete oxidation of the other parts. Such selectively complete anodizing resulted in the patterns of metallic aluminum on anodic alumina. Using the technique, we fabricated microstructures such as line patterns and a simple wiring circuit-board-like structure on the anodic alumina. The aluminum microstructures fabricated by the techniques were embedded in anodic alumina/aluminum sheet, and this technique is promising for applications in electronic packaging and devices. PMID:20356280

  3. High Alumina Refractory Bricks for Electric Arc Furnace Roofs

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 1 Scope This standard specifies the sort, technical requirement, test method, inspection rules, marking, packing, transportation, storage and quality certification of high alumina refractory bricks for electric arc furnace roofs.

  4. Superhydrophobic alumina surface based on stearic acid modification

    International Nuclear Information System (INIS)

    A novel superhydrophobic alumina surface is fabricated by grafting stearic acid layer onto the porous and roughened aluminum film. The chemical and phase structure, morphology, and the chemical state of the atoms at the superhydrophobic surface were investigated by techniques as FTIR, XRD, FE-SEM, and XPS, respectively. Results show that a super water-repellent surface with a contact angle of 154.2o is generated. The superhydrophobic alumina surface takes on an uneven flowerlike structure with many nanometer-scale hollows distribute in the nipple-shaped protrusions, and which is composed of boehmite crystal and γ-Al2O3. Furthermore, the roughened and porous alumina surface is coated with a layer of hydrophobic alkyl chains which come from stearic acid molecules. Therefore, both the roughened structure and the hydrophobic layer endue the alumina surface with the superhydrophobic behavior.

  5. Removing Fluoride Ions with Continously Fed Activated Alumina.

    Science.gov (United States)

    Wu, Yeun C.; Itemaking, Isara Cholapranee

    1979-01-01

    Discussed is the mathematical basis for determining fluoride removal during water treatment with activated alumina. The study indicates that decreasing particle size decreases the pore diffusion effect and increases fluoride removal. (AS)

  6. Geometry of the capillary net in human hearts.

    Science.gov (United States)

    Rakusan, K; Cicutti, N; Spatenka, J; Samánek, M

    1997-01-01

    The geometry of the coronary capillary bed in human hearts was studied using samples obtained during cardiac surgery of children operated for tetralogy of Fallot and samples from fresh normal hearts used for valve harvesting. The results revealed a similar coronary capillary density and heterogeneity of capillary spacing in samples from both groups. A double-staining method was used to distinguish between capillary segments close to the feeding arteriole (proximal capillaries) and segments distant from the arteriole (distal capillaries). In both groups of hearts, capillary segment length was consistently shorter on the venular than the arteriolar portion of the capillary. Similarly, capillary domain areas were also smaller and the resulting capillary supply unit was smaller along venular portions compared to arteriolar regions of the capillary bed. This distinctive geometry would provide advantageous geometric conditions for tissue oxygen supply. PMID:9176723

  7. Resposta da aplicação do 1-MCP em frutos de mamoeiro 'Golden' em diferentes estádios de maturação Responses of 1-MCP applications in 'Golden' papaya fruits on differents maturation stages

    Directory of Open Access Journals (Sweden)

    Maximiliano Silva de Souza

    2009-09-01

    Full Text Available O estudo de fatores que influenciam no processo de amadurecimento é fundamental para o planejamento do processo de comercialização, principalmente em frutos com padrão de respiração climatérico e perecível, como é o caso do mamão. Nesse trabalho, avaliou-se o efeito da aplicação do 1-MCP (1-metilciclopropeno sobre o amadurecimento de frutos de mamoeiro nos estádios 0; 1 e 2 de maturação. O 1-MCP diminui a produção de etileno (≈79% e a taxa respiratória (≈45%, principalmente em frutos no estádio 0 de maturação. O uso deste inibidor da ação do etileno retardou a perda de coloração verde da casca dos frutos, principalmente em frutos nos estádios 0 e 1 de maturação. Houve redução na perda de firmeza do fruto e do mesocarpo nos estádios 1 e 2. Entretanto, em frutos no estádio 0 de maturação, a firmeza do mesocarpo manteve-se alta, o que pode comprometer a aceitação destes frutos pelo consumidor. O teor de sólidos solúveis não foi influenciado pela aplicação do 1-MCP. O efeito do 1-MCP na redução da atividade das enzimas PME e PG foi maior em frutos nos estádios 0 e 1 de maturação em comparação a frutos no estádio 2 de maturação. A atividade da PME demonstrou crescente aumento ao longo do período de armazenamento, porém a atividade da PG permaneceu baixa ao longo dos cinco primeiros dias, com aumento posterior. Os resultados mostraram que a PME exerce influência significativa na perda de firmeza da polpa nos primeiros dias, com atuação posterior da PG. O 1-MCP mostrou-se eficiente em retardar o processo de amadurecimento de frutos de mamoeiro, tornando-se mais eficiente quando associado a estádios de maturação iniciais.The study of factors that influence the process of ripening is critical for planning the marketing process, mainly in standard breathing climacteric and perishing fruits, as it is the case of papaya. In this work it was evaluated the effect of the application of 1-MCP (1

  8. Recent advances in silica-alumina refractory: A review

    Directory of Open Access Journals (Sweden)

    Chaouki Sadik

    2014-06-01

    Full Text Available In this article, the elaboration and the characterization of silica-alumina refractory have been reviewed. Refractory oxides encompass a broad range of unary, binary, and ternary ceramic compounds that can be used in structural, insulating, and other applications. This paper provides a historical perspective on the elaboration and the use of silica-alumina refractory, reviews applications for refractory oxides, describes typical processing routes, overviews fundamental structure–property relations, and summarizes the properties of these materials.

  9. Adsorption of textile dye onto modified immobilized activated alumina

    OpenAIRE

    Wasti, A.; Ali, Awan M.

    2015-01-01

    The study describes the synthesis of modified immobilized activated alumina (MIAA) and its application for the removal of textile dye from aqueous media. Immobilization was carried out by using the sol–gel method while modifications were made during the synthesis by adding powder activated alumina. Batch adsorption experiments were carried out at 20 ± 1 °C to see the effect of different parameters like contact time, stirring rate, initial concentration of the dye and dose of MIAA. The removal...

  10. Preparation of spherical hollow alumina particles by thermal plasma

    International Nuclear Information System (INIS)

    Spherical hollow particles were prepared from solid alumina powders using DC arc thermal plasma, and then spray coating was performed with the as-prepared particles. Operating variables for the hollow particle preparation process were additional plasma gas, input power, and carrier gas flow rate. The spherical hollow alumina particles were produced in the case of using additive gas of H2 or N2, while alumina surface was hardly molten in the pure argon thermal plasma. In addition, the hollow particles were well produced in high power and low carrier gas conditions due to high melting point of alumina. Hollow structure was confirmed by focused ion beam-scanning electron microscopy analysis. Morphology and size distribution of the prepared particles that were examined by field emission-scanning electron microscopy and phase composition of the particles was characterized by X-ray diffraction. In the spray coating process, the as-prepared hollow particles showed higher deposition rate. - Highlights: ► Spherical hollow alumina powder was prepared by non-transferred DC arc plasma. ► Diatomic gasses were added in Ar plasma for high power. ► Prepared hollow alumina powder was efficient for the plasma spray coating

  11. High toughness alumina ceramics with elongated grains developed from seeds

    Institute of Scientific and Technical Information of China (English)

    XIE; Zhipeng; (谢志鹏); GAO; Lichun; (高立春); LI; Wenchao; (李文超); XU; Lihua; (徐利华); WANG; Xidong; (王习东)

    2003-01-01

    In the present paper, the influence of α-Al2O3 seeds and sintering methods on elongated grain growth and fracture toughness is investigated. The preparation of alumina ceramics started with commercial aluminum hydroxide. Abrasives were introduced to the starting materials by wet-grinding of high-purity alumina milling balls. Abrasives, playing the role of seeds, lowered the transformation temperature of aluminum hydroxide to alumina. Microstructures with elongated grains were developed by hot-pressing for the above calcined powders containing α-Al2O3 seeds, and alumina grain shapes changed with the amount of seeds introduced. However, only equiaxed grains were observed for the samples pressureless sintered. Fracture toughness of the alumina ceramics was dramatically improved by elongated grains. For the sample hot-pressed at 1600℃ for 2 h under 40 MPa pressure, fracture toughness reached 7.1 MPa·m1/2, which is much higher than that of normal alumina ceramics without elongated grains. In addition, high flexural strength of 630 MPa for the hot-pressed samples was also obtained.

  12. Characterization and performance of alumina inserts reinforced with zirconia

    International Nuclear Information System (INIS)

    Alumina-based ceramics reinforced with zirconia were produced as inserts to be used as cutting tools. The objective of this work was to characterize and to evaluate the inserts as well as their performance in service. Additions of zirconia varying from 0.05 up to 0.20 wt% were done in alumina in order to select that composition presenting the best mechanical behavior. To do this, four-point bending mechanical strength, hardness and fracture toughness measurements were carried out. The best performance was found for alumina processing 0.010 wt.% of zirconia addition. The addition of zirconia was made with the objective of giving higher toughness to the insert throughout the microcracking reinforcing mechanism. The alumina reinforced inserts were compared with inserts of alumina without zirconia. It was accomplished by performing machining tests onto a SAE 1045 steel. The obtained results indicated that the zirconia reinforcement was able to improve the performance of the alumina cutting tools considerably. (author)

  13. Adsorption of itaconic acid from aqueous solutions onto alumina

    Directory of Open Access Journals (Sweden)

    JELENA J. GULICOVSKI

    2008-08-01

    Full Text Available Itaconic acid, IA (C5H6O4, was investigated as a potential flocculant for the aqueous processing of alumina powders. The adsorption of IA, as a function of its concentration and pH value of the solution, onto the alumina surface was studied by the solution depletion method. The stability of the suspensions in the presence of itaconic acid was evaluated in light of the surface charge of the alumina powder used, the degree of dissociation of IA, as well as the sedimentation behavior and rheology of the suspensions. It was found that the adsorption process is extremely pH dependent; the maximum adsorption of IA onto alumina surface occurring at a pH close to the value of the first IA dissociation constant, pKa1. Also, IA does not influence the value of the point of zero charge of alumina. It was shown that IA represents an efficient flocculant for concentrated acidic alumina suspensions.

  14. Antibacterial activity of zinc oxide-coated nanoporous alumina

    International Nuclear Information System (INIS)

    Highlights: ► Atomic layer deposition was used to deposit ZnO on nanoporous alumina membranes. ► Scanning electron microscopy showed continuous coatings of zinc oxide nanocrystals. ► Activity against B. subtilis, E. coli, S. aureus, and S. epidermidis was shown. - Abstract: Nanoporous alumina membranes, also known as anodized aluminum oxide membranes, are being investigated for use in treatment of burn injuries and other skin wounds. In this study, atomic layer deposition was used for coating the surfaces of nanoporous alumina membranes with zinc oxide. Agar diffusion assays were used to show activity of zinc oxide-coated nanoporous alumina membranes against several bacteria found on the skin surface, including Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis. On the other hand, zinc oxide-coated nanoporous alumina membranes did not show activity against Pseudomonas aeruginosa, Enterococcus faecalis, and Candida albicans. These results suggest that zinc oxide-coated nanoporous alumina membranes have activity against some Gram-positive and Gram-negative bacteria that are associated with skin colonization and skin infection.

  15. Dynamic yield and tensile strengths of spark plasma sintered alumina

    International Nuclear Information System (INIS)

    Fully dense alumina samples with 0.6 μm grain size were produced from alumina powder using Spark Plasma Sintering and tested in two types of VISAR-instrumented planar impact tests. In the tests of the first type the samples of 0.28 to 6-mm thickness were loaded by 1-mm tungsten impactors accelerated up to a velocity of about 1 km/s. These tests were aimed to study the Hugoniot elastic limit (HEL) of the SPS-processed alumina and the decay of the elastic precursor wave with propagation distance. In the second type of test the samples of ∼3-mm thickness were loaded by 1-mm copper impactors accelerated up to velocities 100-1000 m/s. These tests were aimed to study the dynamic tensile (spall) strength of the alumina. The data on tensile fracture of the alumina demonstrate a monotonic decline of the spall strength with the amplitude of the loading stress pulse. The data on the decay of the elastic precursor wave allows for determining the rates of the irreversible (inelastic) strains in the SPS-processed alumina at the initial stages of shock-induced inelastic deformation and, thus, to derive some conclusions concerning the mechanisms responsible of the deformation.

  16. Antibacterial activity of zinc oxide-coated nanoporous alumina

    Energy Technology Data Exchange (ETDEWEB)

    Skoog, S.A. [Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Box 7115, Raleigh, NC 27695-7115 (United States); Bayati, M.R. [Department of Materials Science and Engineering, North Carolina State University, Box 7907, Raleigh, NC 27695-7907 (United States); Petrochenko, P.E. [Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Box 7115, Raleigh, NC 27695-7115 (United States); Division of Biology, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993 (United States); Stafslien, S.; Daniels, J.; Cilz, N. [Center for Nanoscale Science and Engineering, North Dakota State University, 1805 Research Park Drive, Fargo, ND 58102 (United States); Comstock, D.J.; Elam, J.W. [Energy Systems Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Narayan, R.J., E-mail: roger_narayan@msn.com [Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Box 7115, Raleigh, NC 27695-7115 (United States); Department of Materials Science and Engineering, North Carolina State University, Box 7907, Raleigh, NC 27695-7907 (United States)

    2012-07-25

    Highlights: Black-Right-Pointing-Pointer Atomic layer deposition was used to deposit ZnO on nanoporous alumina membranes. Black-Right-Pointing-Pointer Scanning electron microscopy showed continuous coatings of zinc oxide nanocrystals. Black-Right-Pointing-Pointer Activity against B. subtilis, E. coli, S. aureus, and S. epidermidis was shown. - Abstract: Nanoporous alumina membranes, also known as anodized aluminum oxide membranes, are being investigated for use in treatment of burn injuries and other skin wounds. In this study, atomic layer deposition was used for coating the surfaces of nanoporous alumina membranes with zinc oxide. Agar diffusion assays were used to show activity of zinc oxide-coated nanoporous alumina membranes against several bacteria found on the skin surface, including Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis. On the other hand, zinc oxide-coated nanoporous alumina membranes did not show activity against Pseudomonas aeruginosa, Enterococcus faecalis, and Candida albicans. These results suggest that zinc oxide-coated nanoporous alumina membranes have activity against some Gram-positive and Gram-negative bacteria that are associated with skin colonization and skin infection.

  17. CCL2/MCP-I genotype-phenotype relationship in latent tuberculosis infection.

    Science.gov (United States)

    Hussain, Rabia; Ansari, Ambreen; Talat, Najeeha; Hasan, Zahra; Dawood, Ghaffar

    2011-01-01

    Among the known biomarkers, chemokines, secreted by activated macrophages and T cells, attract groups of immune cells to the site of infection and may determine the clinical outcome. Association studies of CCL-2/MCP-1 -2518 A/G functional SNP linked to high and low phenotypes with tuberculosis disease susceptibility have shown conflicting results in tuberculosis. Some of these differences could be due the variability of latent infection and recent exposure in the control groups. We have therefore carried out a detailed analysis of CCL-2 genotype SNP -2518 (A/G transition) with plasma CCL-2 levels and related these levels to tuberculin skin test positivity in asymptomatic community controls with no known exposure to tuberculosis and in recently exposed household contacts of pulmonary tuberculosis patients. TST positivity was linked to higher concentrations of plasma CCL2 (Mann Whitney U test; p = 0.004) and was more marked when the G allele was present in TST+ asymptomatic controls (A/G; p = 0.01). Recent exposure also had a significant effect on CCL-2 levels and was linked to the G allele (p = 0.007). Therefore association studies for susceptibility or protection from disease should take into consideration the PPD status as well as recent exposure of the controls group used for comparison. Our results also suggest a role for CCL-2 in maintaining the integrity of granuloma in asymptomatic individuals with latent infection in high TB burden settings. Therefore additional studies into the role of CCL-2 in disease reactivation and progression are warranted. PMID:21991356

  18. CCL2/MCP-I genotype-phenotype relationship in latent tuberculosis infection.

    Directory of Open Access Journals (Sweden)

    Rabia Hussain

    Full Text Available Among the known biomarkers, chemokines, secreted by activated macrophages and T cells, attract groups of immune cells to the site of infection and may determine the clinical outcome. Association studies of CCL-2/MCP-1 -2518 A/G functional SNP linked to high and low phenotypes with tuberculosis disease susceptibility have shown conflicting results in tuberculosis. Some of these differences could be due the variability of latent infection and recent exposure in the control groups. We have therefore carried out a detailed analysis of CCL-2 genotype SNP -2518 (A/G transition with plasma CCL-2 levels and related these levels to tuberculin skin test positivity in asymptomatic community controls with no known exposure to tuberculosis and in recently exposed household contacts of pulmonary tuberculosis patients. TST positivity was linked to higher concentrations of plasma CCL2 (Mann Whitney U test; p = 0.004 and was more marked when the G allele was present in TST+ asymptomatic controls (A/G; p = 0.01. Recent exposure also had a significant effect on CCL-2 levels and was linked to the G allele (p = 0.007. Therefore association studies for susceptibility or protection from disease should take into consideration the PPD status as well as recent exposure of the controls group used for comparison. Our results also suggest a role for CCL-2 in maintaining the integrity of granuloma in asymptomatic individuals with latent infection in high TB burden settings. Therefore additional studies into the role of CCL-2 in disease reactivation and progression are warranted.

  19. Semiconductor Yield Analysis and Multi-Chip Package (MCP) Die Pairing Optimization using Machine Learning

    Institute of Scientific and Technical Information of China (English)

    Randall Goodwin; Russell Miller; Eugene Tuv; Alexander Borisov

    2006-01-01

    Machine Learning, Artificial Intelligence (AI) and Statistical Learning are related mathematical fields which utilize computer algorithms to create models for the purposes of data description and/or prediction. Some well known examples include biometric identification and authorization systems, speech recognition and user targeted internet advertising. Statistical Learning, which we will use in this paper, also has many applications in semiconductor manufacturing.Some of the challenging characteristics of semiconductor data include high dimensionality, mixtures of categorical and numeric data, non-randomly missing data, non-Gaussian and multimodal distributions, nonlinear complex relationships, noise, outliers and temporal dependencies. These challenges are becoming particularly acute as the quantity of available data increases and the ability to trace lots, wafers, die, and packages throughout the full fab, wafer test, assembly and final test manufacturing flow improves. Statistical-learning techniques are applied to address these challenges. In this paper we discuss the advancement and applications of Tree based classification and regression methods to semiconductor data. We begin the paper with a description of the problem, followed by and overview of the statistical-learning techniques we use in our case studies. We then describe how the challenges presented by semiconductor data were addressed with original extensions to tree-based and kernel-based methods. Next, we review four case studies: home sales price prediction, signal identification/separation, final speed bin classification and die pairing optimization for Multi-Chip Packages (MCP). Results from the case studies demonstrate how statistical-learning addresses the challenges presented by semiconductor manufacturing data and enables improved data discovery and prediction when compared to traditional statistical approaches.

  20. Spiral ligament fibrocyte-derived MCP-1/CCL2 contributes to inner ear inflammation secondary to nontypeable H. influenzae-induced otitis media

    Directory of Open Access Journals (Sweden)

    Lim David J

    2010-10-01

    Full Text Available Abstract Background Otitis media (OM, one of the most common pediatric infectious diseases, causes inner ear inflammation resulting in vertigo and sensorineural hearing loss. Previously, we showed that spiral ligament fibrocytes (SLFs recognize OM pathogens and up-regulate chemokines. Here, we aim to determine a key molecule derived from SLFs, contributing to OM-induced inner ear inflammation. Methods Live NTHI was injected into the murine middle ear through the tympanic membrane, and histological analysis was performed after harvesting the temporal bones. Migration assays were conducted using the conditioned medium of NTHI-exposed SLFs with and without inhibition of MCP-1/CCL2 and CCR2. qRT-PCR analysis was performed to demonstrate a compensatory up-regulation of alternative genes induced by the targeting of MCP-1/CCL2 or CCR2. Results Transtympanic inoculation of live NTHI developed serous and purulent labyrinthitis after clearance of OM. THP-1 cells actively migrated and invaded the extracellular matrix in response to the conditioned medium of NTHI-exposed SLFs. This migratory activity was markedly inhibited by the viral CC chemokine inhibitor and the deficiency of MCP-1/CCL2, indicating that MCP-1/CCL2 is a main attractant of THP-1 cells among the SLF-derived molecules. We further demonstrated that CCR2 deficiency inhibits migration of monocyte-like cells in response to NTHI-induced SLF-derived molecules. Immunolabeling showed an increase in MCP-1/CCL2 expression in the cochlear lateral wall of the NTHI-inoculated group. Contrary to the in vitro data, deficiency of MCP-1/CCL2 or CCR2 did not inhibit OM-induced inner ear inflammation in vivo. We demonstrated that targeting MCP-1/CCL2 enhances NTHI-induced up-regulation of MCP-2/CCL8 in SLFs and up-regulates the basal expression of CCR2 in the splenocytes. We also found that targeting CCR2 enhances NTHI-induced up-regulation of MCP-1/CCL2 in SLFs. Conclusions Taken together, we suggest that

  1. Pseudogenization of the MCP-2/CCL8 chemokine gene in European rabbit (genus Oryctolagus, but not in species of Cottontail rabbit (Sylvilagus and Hare (Lepus

    Directory of Open Access Journals (Sweden)

    van der Loo Wessel

    2012-08-01

    Full Text Available Abstract Background Recent studies in human have highlighted the importance of the monocyte chemotactic proteins (MCP in leukocyte trafficking and their effects in inflammatory processes, tumor progression, and HIV-1 infection. In European rabbit (Oryctolagus cuniculus one of the prime MCP targets, the chemokine receptor CCR5 underwent a unique structural alteration. Until now, no homologue of MCP-2/CCL8a, MCP-3/CCL7 or MCP-4/CCL13 genes have been reported for this species. This is interesting, because at least the first two genes are expressed in most, if not all, mammals studied, and appear to be implicated in a variety of important chemokine ligand-receptor interactions. By assessing the Rabbit Whole Genome Sequence (WGS data we have searched for orthologs of the mammalian genes of the MCP-Eotaxin cluster. Results We have localized the orthologs of these chemokine genes in the genome of European rabbit and compared them to those of leporid genera which do (i.e. Oryctolagus and Bunolagus or do not share the CCR5 alteration with European rabbit (i.e. Lepus and Sylvilagus. Of the Rabbit orthologs of the CCL8, CCL7, and CCL13 genes only the last two were potentially functional, although showing some structural anomalies at the protein level. The ortholog of MCP-2/CCL8 appeared to be pseudogenized by deleterious nucleotide substitutions affecting exon1 and exon2. By analyzing both genomic and cDNA products, these studies were extended to wild specimens of four genera of the Leporidae family: Oryctolagus, Bunolagus, Lepus, and Sylvilagus. It appeared that the anomalies of the MCP-3/CCL7 and MCP-4/CCL13 proteins are shared among the different species of leporids. In contrast, whereas MCP-2/CCL8 was pseudogenized in every studied specimen of the Oryctolagus - Bunolagus lineage, this gene was intact in species of the Lepus - Sylvilagus lineage, and was, at least in Lepus, correctly transcribed. Conclusion The biological function of a gene was often

  2. Effect of maturity and cold storage on ethylene biosynthesis and ripening in ‘Bartlett’ pears treated after harvest with 1-MCP

    Science.gov (United States)

    To further our understanding of the response of ‘Bartlett’ pear fruit to 1-methylcyclopropene (1-MCP) and their ability to recover the capacity to ripen, ‘Bartlett’ pears were treated with 0.3 µL L-1 1-MCP for 12 h at 20 °C immediately after harvest in two seasons and to pear fruit of four maturitie...

  3. Comparative effect of genistein and daidzein on the expression of MCP-1, eNOS, and cell adhesion molecules in TNF-α-stimulated HUVECs

    OpenAIRE

    Cho, Hye Yeon; Park, Chung Mu; Kim, Mi Jeong; Chinzorig, Radnaabazar; Cho, Chung Won; Song, Young Sun

    2011-01-01

    We compared the effects of genistein and daidzein on the expression of chemokines, cell adhesion molecules (CAMs), and endothelial nitric oxide synthase (eNOS) in tumor necrosis factor (TNF)-α-stimulated human umbilical vascular endothelial cells (HUVECs). TNF-α exposure significantly increased expression of monocyte chemoattractant protein (MCP)-1, vascular adhesion molecule (VCAM)-1, and intercellular adhesion molecule-1. Genistein significantly decreased MCP-1 and VCAM-1 production in a do...

  4. Genome-wide association replicates the association of Duffy antigen receptor for chemokines (DARC) polymorphisms with serum monocyte chemoattractant protein-1 (MCP-1) levels in Hispanic children

    OpenAIRE

    Voruganti, V. Saroja.; Laston, Sandra; Haack, Karin; Mehta, Nitesh R.; Smith, C. Wayne; Cole, Shelley A.; Butte, Nancy F.; Comuzzie, Anthony G.

    2012-01-01

    Obesity is associated with a chronic low inflammatory state characterized by elevated levels of chemokines. Monocyte chemoattractant protein-1 (MCP-1) is a member of the cysteine-cysteine (CC) chemokine family and is increased in obesity. The purpose of this study was to identify loci regulating serum MCP-1 in obese Hispanic children from the Viva La Familia Study. A genome-wide association (GWA) analysis was performed in 815 children, ages 4-19 years, using genotypes assayed with the Illumin...

  5. "Getting the best sensitivity from on-capillary fluorescence detection in capillary electrophoresis" - A tutorial.

    Science.gov (United States)

    Galievsky, Victor A; Stasheuski, Alexander S; Krylov, Sergey N

    2016-09-01

    Capillary electrophoresis with Laser-Induced Fluorescence (CE-LIF) detection is being applied to new analytical problems which challenge both the power of CE separation and the sensitivity of LIF detection. On-capillary LIF detection is much more practical than post-capillary detection in a sheath-flow cell. Therefore, commercial CE instruments utilize solely on-capillary CE-LIF detection with a Limit of Detection (LOD) in the nM range, while there are multiple applications of CE-LIF that require pM or lower LODs. This tutorial analyzes all aspects of on-capillary LIF detection in CE in an attempt to identify means for improving LOD of CE-LIF with on-capillary detection. We consider principles of signal enhancement and noise reduction, as well as relevant areas of fluorophore photochemistry and fluorescent microscopy. PMID:27543015

  6. Effect of the Cooling System and 1-MCP on the Incidence of Superficial Scald in ‘Granny Smith’ Apples Efecto del Sistema de Enfriamiento y 1-MCP sobre la Incidencia de Escaldado Superficial en Manzanas ‘Granny Smith’

    Directory of Open Access Journals (Sweden)

    Claudia Moggia

    2009-09-01

    Full Text Available A study was carried out to determine the effects of two cooling systems and the application of 1-methylcyclopropene (1-MCP, SmartFreshTM on the incidence of superficial scald in apples (Malus domestica Borkh. cv. Granny Smith. Fruit were collected from a commercial orchard (Colbún, Maule Region, Chile during 2004-2005 season. A completely randomized design was used in a 2 x 2 factorial arrangement, using cooling systems (normal and step-wise cooling and application of 1-MCP (0 and 625 nL L-1 i.a. as the main factors. Fruit from normal cooling were kept at 0 °C throughout the storage period (180 days. Step-wise cooling consisted of storing the fruit at 10 °C for 10 days; 4 °C for the next 20 days and 0 °C for the remaining 150 days. Every month, maturity indices and the chemicals, global antioxidant content (AO, α-farnesene (AF and conjugated trienes (TC, were measured. Incidence of superficial scald was determined after 180 days of storage, plus 10 days at 20 °C . The application of 1-MCP with both cooling systems was capable of maintaining firmness values around 8,2 kg up to the end of the storage period, as well as decreasing the concentration of AF, TC and AO during storage. Incidence of superficial scald on fruit with 1-MCP was 0%, regardless of the type of cooling. Among treatments without 1-MCP, step-wise-cooling was more effective in preventing superficial scald, resulting in 1.3% incidence compared to 75.6% with the normal cooling system. Nevertheless, from the fourth month onwards firmness was lower than that required for export.Se desarrolló un estudio para determinar el efecto de dos sistemas de enfriamiento y la aplicación de 1-metilciclopropeno (1-MCP, SmartFreshTM sobre la incidencia de escaldado superficial en manzanas (Malus domestica Borkh. cv. Granny Smith, colectadas de un huerto comercial (Colbún, Región del Maule, Chile durante la temporada 2004-2005. El ensayo consistió en un diseño completamente al azar con

  7. Monte Carlo Simulations of High-speed, Time-gated MCP-based X-ray Detectors: Saturation Effects in DC and Pulsed Modes and Detector Dynamic Range

    Energy Technology Data Exchange (ETDEWEB)

    Craig Kruschwitz, Ming Wu, Ken Moy, Greg Rochau

    2008-10-31

    We present here results of continued efforts to understand the performance of microchannel plate (MCP)–based, high-speed, gated, x-ray detectors. This work involves the continued improvement of a Monte Carlo simulation code to describe MCP performance coupled with experimental efforts to better characterize such detectors. Our goal is a quantitative description of MCP saturation behavior in both static and pulsed modes. We have developed a new model of charge buildup on the walls of the MCP channels and measured its effect on MCP gain. The results are compared to experimental data obtained with a short-pulse, high-intensity ultraviolet laser; these results clearly demonstrate MCP saturation behavior in both DC and pulsed modes. The simulations compare favorably to the experimental results. The dynamic range of the detectors in pulsed operation is of particular interest when fielding an MCP–based camera. By adjusting the laser flux we study the linear range of the camera. These results, too, are compared to our simulations.

  8. Annealing Would Improve beta" - Alumina Solid Electrolyte

    Science.gov (United States)

    Williams, Roger; Homer, Margie; Ryan, Margaret; Cortez, Roger; Shields, Virgil; Kisor, Adam

    2003-01-01

    A pre-operational annealing process is under investigation as a potential means of preventing a sudden reduction of ionic conductivity in a Beta"-alumina solid electrolyte (BASE) during use. On the basis of tests, the sudden reduction of ionic conductivity, followed by a slow recovery, has been found to occur during testing of the solid electrolyte and electrode components of an alkali metal thermal-to-electric converter (AMTEC) cell. At this time, high-temperature tests of limited duration have indicated the superiority of the treated BASE, but reproducible tests over thousands of hours are necessary to confirm that microcracking has been eliminated. The ionic conductivity of the treated BASE is also measured to be higher than untreated BASE at 1,073 K in low-pressure sodium vapor. Microcracking resulting in loss of conductivity was not observed with treated BASE in one high-temperature experiment, but this result must be duplicated over very long testing times to be sure of the effect. Shorter annealing times (10 to 20 hours) were found to result in significantly less loss of mass; it may be necessary for the packed powder mixture to evolve some Na2O before the Na2O can leave the ceramic.

  9. Microstructure Analysis of Thermally Etched Alumina Ceramics

    Directory of Open Access Journals (Sweden)

    Fudurić Jelača, M.

    2008-12-01

    Full Text Available Ceramography is the art and science of preparation, examination, and evaluation of ceramic microstructures. Microstructure is the structure level approximately 0.1 to 100 μ m between the wavelength of visible light and the resolution limit of the naked eye. The microstructure includes most grains, secondary phases, grain boundaries, pores, microcracks, hardness microindentations. Investigation and evaluation of ceramic microstructure is very important because a number of mechanical, optical, thermal, electrical and other properties of ceramics are significantly affected by the microstructure. The techniques for ceramographic preparation are divided into five parts: sawing, mounting, grinding, polishing and etching.In this paper a method for preparation of a cold isostatically pressed high purity alumina ceramics (α-Al2O3 is described. Microstructure analysis of prepared ceramics was performed by means of optical microscopy (OM, scanning electron microscopy (SEM and atomic force microscopy (AFM. Porosity is determined on the polished sample; grain size is measured after thermal etching. The mean grain diameter is determined by means of lineal-intercept method, circular-intercept method and image analysis.

  10. Coprecipitated nickel-alumina methanation catalysts

    International Nuclear Information System (INIS)

    In the last few years there has been a renewed interest in the methanation reaction CO+3H2=CH4+H2O. The investigations described in this thesis were performed in relation to the application of this reaction, within the framework of the so-called 'NFE' project, also called 'ADAM' and 'EVA' project. This project, which has been under investigation in West Germany for some years, aims at the investigation of the feasibility of transporting heat from a nuclear high temperature reactor by means of a chemical cycle. A promising possibility to realize such a cycle exists in applying the combination of the endothermic steam reforming of methane and the exothermic methanation reaction. This thesis describes the investigations into a certain type of methanation catalyst, viz. a coprecipitated nickel-alumina catalyst, with the aim to give more insight into the interrelationship between the preparation conditions on the one hand and catalyst properties such as activity and stability on the other hand. (Auth.)

  11. Thermal Conductivity of Alumina and Silica Nanofluids

    Science.gov (United States)

    Castellanos, Julian G. Bernal

    This thesis studies the effects of the base fluid, particle type/size, and volumetric concentration on the thermal conductivity of Alumina and Silica nanofluids. The effects of base fluid were observed by preparing samples using ethylene glycol (EG), water, and mixtures of EG/water as the base fluid and Al2O3 (10 nm) nanoparticles. The particles type/size and volumetric concentration effects were tested by preparing samples of nanofluids using Al2O3 (10nm), Al2O3 (150nm), SiO2 (15 nm), and SiO2 (80 nm) nanoparticles and ionized water as base fluid at different volumetric concentrations. All samples were mixed using a sonicator for 30 minutes and a water circulator to maintain the sample at room temperature. The thermal conductivity was measured using a Thermtest Transient Plane Source TPS 500S. The effects of gravity, Brownian motion and thermophoresis were also studied. EG produced the highest thermal conductivity enhancement out of all base fluids tested. Smaller particle size produced a higher enhancement of thermal conductivity, while the volumetric concentration did not have a significant effect in the thermal conductivity enhancement. Finally, gravity, Brownian diffusion and thermophoresis effects played a role in the total enhancement of the thermal conductivity. The nanoparticles were observed to settle rapidly after sonication suggesting gravity effects may play a significant role.

  12. Capillary electrochromatography using fibers as stationary phases.

    Science.gov (United States)

    Jinno, K; Watanabe, H; Saito, Y; Takeichi, T

    2001-10-01

    Fiber-packed capillary columns have been evaluated in chromatographic performance in capillary electrochromatography (CEC). The change of electroosmotic flow (EOF) velocity and selectivity using different kinds of fiber materials was examined. Although the EOF velocity among the different fiber packed columns was almost the same, retention of parabens was larger on the Kevlar-packed column than on the Zylon-packed one, and was larger on the as-span-type fiber-packed column than on the high-modulus-type packed one. Using 200 microm ID x 5 cm Kevlar packed column combined with a 100 microm ID x 20 cm precolumn capillary and a 530 microm ID x 45 cm postcolumn capillary, the separation of three parabens within 30 s was achieved. Other compounds were also separated in a few minutes by the fiber-packed CEC method. PMID:11669512

  13. Uptake of water droplets by nonwetting capillaries

    CERN Document Server

    Willmott, Geoff R; Hendy, Shaun C

    2010-01-01

    We present direct experimental evidence that water droplets can spontaneously penetrate non-wetting capillaries, driven by the action of Laplace pressure due to high droplet curvature. Using high-speed optical imaging, microcapillaries of radius 50 to 150 micron, and water microdroplets of average radius between 100 and 1900 micron, we demonstrate that there is a critical droplet radius below which water droplets can be taken up by hydrophobised glass and polytetrafluoroethylene (PTFE) capillaries. The rate of capillary uptake is shown to depend strongly on droplet size, with smaller droplets being absorbed more quickly. Droplet size is also shown to influence meniscus motion in a pre-filled non-wetting capillary, and quantitative measurements of this effect result in a derived water-PTFE static contact angle between 96 degrees and 114 degrees. Our measurements confirm recent theoretical predictions and simulations for metal nanodroplets penetrating carbon nanotubes (CNTs). The results are relevant to a wide ...

  14. Capillary Electrophoresis coupled with Automated Fraction Collection

    OpenAIRE

    Huge, Bonnie Jaskowski; Flaherty, Ryan; Dada, Oluwatosin O.; Dovichi, Norman J.

    2014-01-01

    A fraction collector based on a drop-on-demand ink-jet printer was developed to interface capillary zone electrophoresis with a 96 well microtiter plate. We first evaluated the performance of the collector by using capillary zone electrophoresis to analyze a 1 mM solution of tetramethylrhodamine; a fluorescent microtiter plate reader was then used to detect the analyte and characterize fraction carryover between wells. Relative standard deviation in peak height was 20% and the relative standa...

  15. The capillary electrophoresis of the influenza viruses

    Czech Academy of Sciences Publication Activity Database

    Horká, Marie; Kubesová, Anna; Kubíček, O.; Kubíčková, Z.; Rosenbergová, K.; Šlais, Karel

    Tallinn: Tallinn University of Technology, 2009 - (Borissova, M.; Vaher, M.). s. 93 ISBN 978-9985-59-930-3. [Nordic Separation Science Society (NoSSS) International Conference /5./. 26.08.2009-29.08.2009, Tallinn] R&D Projects: GA AV ČR IAAX00310701 Institutional research plan: CEZ:AV0Z40310501 Keywords : capillary isoelectric focusing * capillary electrophoresis * influenza swine and equine viruses Subject RIV: CB - Analytical Chemistry, Separation

  16. Selectivity and detection in capillary electrophoresis

    OpenAIRE

    Khaled, Maha Yehia

    1994-01-01

    This work is a contribution to the minimization of some of the selectivity and detection limitations in capillary electrophoresis. A more practical design of an electrochemical detector is introduced with simultaneous on-line UV detection (1), for the selective detection of a number of pungent and neurological compounds, the piperines and the capsacinoids. Commercially available microelectrodes together with large 25 μm id fused silica capillary columns are used for the fir...

  17. EFFECT OF SPINEL ADDITION ON THE SINTERING BEHAVIOR AND MICROSTRUCTURE OF ALUMINA-SPINEL CERAMICS

    OpenAIRE

    Emre Yalamac

    2014-01-01

    Sintering behaviors of alumina-spinel powder mixtures were investigated up to 1600oC using a vertical dilatometer. Final density and microstructure of pure alumina, magnesium aluminate spinel (MgAl2O4) ceramics and ceramic composites with different alumina-spinel ratio were examined. As a result, the densification and final density of alumina-spinel composites were affected by addition of 10 wt. % and 20 wt. % spinel into alumina. Non-stoichiometric alumina-rich spinel phase was d...

  18. Ion polarization behavior in alumina under pulsed gate bias stress

    International Nuclear Information System (INIS)

    Alkali metal ion incorporation in alumina significantly increases alumina capacitance by ion polarization. With high capacitance, ion-incorporated aluminas become promising high dielectric constant (high-k) gate dielectric materials in field-effect transistors (FETs) to enable reduced operating voltage, using oxide or organic semiconductors. Alumina capacitance can be manipulated by incorporation of alkali metal ions, including potassium (K+), sodium (Na+), and lithium (Li+), having different bond strengths with oxygen. To investigate the electrical stability of zinc tin oxide-based transistors using ion incorporated alumina as gate dielectrics, pulsed biases at different duty cycles (20%, 10%, and 2% representing 5 ms, 10 ms, and 50 ms periods, respectively) were applied to the gate electrode, sweeping the gate voltage over series of these cycles. We observed a particular bias stress-induced decrease of saturation field-effect mobility accompanied by threshold voltage shifts (ΔVth) in potassium and sodium-incorporated alumina (abbreviated as PA and SA)-based FETs at high duty cycle that persisted over multiple gate voltage sweeps, suggesting a possible creation of new defects in the semiconductor. This conclusion is also supported by the greater change in the mobility-capacitance (μC) product than in capacitance itself. Moreover, a more pronounced ΔVth over shorter times was observed in lithium-incorporated alumina (abbreviated as LA)-based transistors, suggesting trapping of electrons in existing interfacial states. ΔVth from multiple gate voltage sweeps over time were fit to stretched exponential forms. All three dielectrics show good stability using 50-ms intervals (20-Hz frequencies), corresponding to 2% duty cycles

  19. Implementation of moire-schlieren deflectometry on a small scale fast capillary plasma discharge

    International Nuclear Information System (INIS)

    We present the results of an implementation of a refractive diagnostic to study fast dynamics in capillary discharges. It consists of a moire-schlieren deflectometry technique that provides a quantitative analysis of the refractive index gradients. The technique is composed of an angular deflection mapping system (moire deflectometry) and a spatial Fourier filter (schlieren). Temporal resolution of 12 ps, 50 μm of spatial resolution and minimum detectable gradient of (∇ne)min=6x1018cm-4 were obtained. With these parameters, a large aspect ratio capillary discharge of 15 ns half period current was studied; the diagnostic was implemented axially along the alumina tube of 1.6 mm inner diameter and 21 mm length. The detectable electron density for these conditions was 1x1017cm-3. From the interpretation of the fringe displacement, we are able to measure the velocity of the radial compression wave and the compression ratio due to the Lorentz force. On axis, electron densities of the order of 5x1017cm-3 were obtained at the time of maximum soft x-ray emission.

  20. The mechanical reliability of alumina scales and coatings

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, K.B.; Pruebner, K.; Tortorelli, P.F. [Oak Ridge National Lab., TN (United States)

    1996-08-01

    The mechanical integrity of oxide scales ultimately determines their ability to protect materials from corrosion and other environmental effects arising from deleterious reactions with gases and condensable products. The microstructure and mechanical behavior of alumina products thermally grown or deposited on Fe-28 at.% Al intermetallic alloys are being characterized in order to develop the knowledge and means to control the mechanical reliability of alumina scales by microstructural manipulation through design and processing. Mechanical characterization involved gravimetric data from cyclic oxidation experiments, in-situ observation of oxidized specimens undergoing flexural loading in a scanning electron microscope, and measurements of hardness, elastic modulus and cracking resistance by nanoindentation. Values of cracking thresholds for Al{sub 2}O{sub 3} scales were consistent with other measurements for surface and bulk alumina. The oxidation behavior of Fe{sub 3}Al alloys coated with a thin (0.5 - 1 {mu}m) alumina film deposited by plasma synthesis has been studied. During exposure in the oxidizing environment, new oxide was formed between the coating and the substrate. The presence of the deposited amorphous oxide inhibited the subsequent thermal oxidation of the metal. Because the thermally grown alumina forms under the deposit, the adherence of the coating is controlled by the strength of the metal/oxide interface that develops during oxidation.

  1. Plasma Processes : Plasma sprayed alumina coatings for radiation detector development

    Indian Academy of Sciences (India)

    Mary Alex; V Balagi; K R Prasad; K P Sreekumar; P V Ananthapadmanabhan

    2000-11-01

    Conventional design of radiation detectors uses sintered ceramic insulating modules. The major drawback of these ceramic components is their inherent brittleness. Ion chambers, in which these ceramic spacers are replaced by metallic components with plasma spray coated alumina, have been developed in our Research Centre. These components act as thin spacers that have good mechanical strength as well as high electrical insulation and replace alumina insulators with the same dimensions. As a result, the design of the beam loss monitor ion chamber for CAT could be simplified by coating the outer surface of the HT electrode with alumina. One of the chambers developed for isotope calibrator for brachytherapy gamma sources has its outer aluminium electrode (60 mm dia × 220 mm long) coated with 250 thick alumina (97%) + titania (3%). In view of potential applications in neutron-sensitive ion chambers used in reactor control instrumentation, studies were carried out on alumina 100 to 500 thick coatings on copper, aluminium and SS components. The electrical insulation varied from 108 ohms to 1012 ohms for coating thicknesses above 200 . The porosity in the coating resulted in some fall in electrical insulation due to moisture absorption. An improvement could be achieved by providing the ceramic surface with moisture-repellent silicone oil coating. Irradiation at Apsara reactor core location showed that the coating on aluminium was found to be unaffected after exposure to 1017 nvt fluence.

  2. Aluminas with dispersoids. Tribologic properties and in vivo aging.

    Science.gov (United States)

    Mandrino, A; Moyen, B; Ben Abdallah, A; Treheux, D; Orange, D

    1990-07-01

    Three base alumina ceramics with dispersoids: monoclinic zirconia alumina (A5Z), tetragonal zirconia alumina (A20Z) and aluminalon (Aa20) have been investigated because of their improved mechanical properties with reference to pure alumina (AI203). Bending strength and fracture toughness are twice higher than alumina for the most toughened. These two parameters were measured by four-points bending tests after 1 week, 1, 2, 3, 6, 12 months of non loaded in vivo aging in wistar rats. They showed a little decrease for AI203 and Aa20 and a total stability for A5Z and A20Z even after one year. For tribologic study of the ceramic/polyethylene combination, cylinder against plane and pin on flat tests were conducted on an alternative movement with hip parameters of speed and load in presence of ringer solution. For the most representative test (pin on disk), the friction coefficients were nearly the same for all materials but UHMWPE wear volume was twice lower against A20Z than against AI203. A20Z/UHMWPE combination would be very interesting as new friction couple for total hip arthroplasty. Further studies are currently conducted. PMID:2397268

  3. Enriched fluoride sorption using alumina/chitosan composite

    International Nuclear Information System (INIS)

    Alumina possesses an appreciable defluoridation capacity (DC) of 1566 mg F-/kg. In order to improve its DC, it is aimed to prepare alumina polymeric composites using the chitosan. Alumina/chitosan (AlCs) composite was prepared by incorporating alumina particles in the chitosan polymeric matrix, which can be made into any desired form viz., beads, candles and membranes. AlCs composite displayed a maximum DC of 3809 mg F-/kg than the alumina and chitosan (52 mg F-/kg). The fluoride removal studies were carried out in batch mode to optimize the equilibrium parameters viz., contact time, pH, co-anions and temperature. The equilibrium data was fitted with Freundlich and Langmuir isotherms to find the best fit for the sorption process. The calculated values of thermodynamic parameters indicate the nature of sorption. The surface characterisation of the sorbent was performed by FTIR, AFM and SEM with EDAX analysis. A possible mechanism of fluoride sorption by AlCs composite has been proposed. Suitability of AlCs composite at field conditions was tested with a field sample taken from a nearby fluoride-endemic village. This work provides a potential platform for the development of defluoridation technology.

  4. Synthesis and structural evaluation of freeze-cast porous alumina

    International Nuclear Information System (INIS)

    In this work we fabricated alumina samples by the freeze-casting technique using tert-butanol as the solvent. The prepared materials were examined by scanning electron microscopy and X-ray microtomography. Next, they were coated with sol–gel silica films by dip-coating. Permeability tests were carried out in order to assess the permeation behavior of the materials processed in this study. We observed that the sintering time and alumina loading showed a remarkable effect on both the structural properties and flexural strength of the freeze-cast samples. Nitrogen adsorption tests revealed that the silica prepared in this study exhibited a microporous structure. It was observed that the presence of silica coatings on the alumina surface decreased the CO2 permeance by about one order of magnitude. Because of the similar kinetic diameters of nitrogen and carbon dioxide, the CO2/N2 system showed a separation efficiency that was lower than that observed for the He/CO2 and He/N2 systems. We noticed that increasing the feed pressure improved the separation capacity of the obtained materials. - Highlights: • Porous alumina samples obtained by the freeze-casting technique • Microporous silica coating prepared by a simple sol–gel dip-coating methodology • Samples examined by SEM, μ-CT, and nitrogen sorption tests • Mechanical tests were carried out in the freeze-cast samples. • The presence of silica coatings on the alumina surface decreased the CO2 permeance

  5. The nature of hydrogen in γ-alumina

    International Nuclear Information System (INIS)

    Gibbs free energy models are derived from the calculated electronic and phonon structure of two possible models of γ-alumina, a defective spinel phase and a hydrogenated spinel phase. The intrinsic vacancies and hydrogen in the two structural models give rise to a considerable configurational (residual) entropy and significantly contribute to thermodynamic stability and physical-chemical properties of γ-alumina, which was neglected in previous studies but considered in this work. The electronic densities of states, calculated using a hybrid functional for the two structural models of γ-alumina, are presented. The dynamic stability of the two phases is confirmed by full-spectrum phonon calculations. The two phases share many similarities in their electronic structure, but can be distinguished by their vibrational spectra and specific heat. The defective spinel is found to be the ground state of γ-alumina, while the hydrogenated spinel to be a metastable phase. However, dehydration of the metastable phase into the ground state is expected to be slow due to the low diffusion rate of H, which leaves hydrogen as a locked-in impurity in γ-alumina.

  6. sPLA2-IIA Augments Oxidized LDL-Induced MCP-1 Expression in Vitro Through Activation of Akt

    Directory of Open Access Journals (Sweden)

    Yongjun Guo

    2015-10-01

    Full Text Available Background/Aims: Group IIA secretory phospholipase A2 (sPLA2-IIA has an important role in atherosclerosis. In this study, we explored whether sPLA2-IIA overexpression could promote atherosclerosis in normal environment alone or with other inflammatory factors. Methods: Human aortic smooth muscle cells (HASMCs were transduced with Lv-GFP-sPLA2-IIA, a plasmid containing sPLA2-IIA coupled with green fluorescent protein (GFP. Cells were incubated in the presence or absence of oxidized low-density lipoprotein (LDL, sPLA2 inhibitor LY315920 or PI3K/Akt inhibitor LY294002. The mRNA expression and protein secretion of monocyte chemoattractant protein-1 (MCP-1 were assessed by quantitative real-time polymerase chain reaction (QRT-PCR and enzyme-linked immunosorbent assay (ELISA, respectively. Phosphorylation of Akt was examined by western blotting. Results: Lv-GFP-sPLA2-IIA-transduced HASMCs remained fluorescent during 72 h of the study period with infection ratio of around 80%. The mRNA expression and protein secretion of MCP-1was not altered in groups of HASMCs, Lv-GFP transduced and Lv-GFP-sPLA2-IIA-transduced HASMCs (p>0.05, but was significantly increased in the presence of oxidized LDL especially in Lv-GFP-sPLA2-IIA transduction group (ppConclusions: Overexpression of sPLA2-IIA does not alter MCP-1 level at baseline, but could enhance the atherogenic effect of oxidized LDL in HASMCs, at least partly due to activation of Akt. These findings may provide a strategy for treatment of inflammatory cardiovascular diseases.

  7. Sulforaphane inhibits de novo synthesis of IL-8 and MCP-1 in human epithelial cells generated by cigarette smoke extract.

    Science.gov (United States)

    Starrett, Warren; Blake, David J

    2011-06-01

    Chronic obstructive pulmonary disease (COPD) is currently the fifth leading cause of death worldwide. Exposure to cigarette smoke (CS) is the primary factor associated with the COPD development. CS activates epithelial cells to secrete chemokines such as interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) that recruit neutrophils and macrophages to the lung. These inflammatory cells then release additional chemokines and cytokines leading to chronic inflammation that initiates apoptosis in epithelial and endothelial cells and destruction of alveolar structure. Pulmonary epithelium responds to oxidative stress mediated by CS through activating NRF2-dependent pathways, leading to an increased expression of antioxidant and cytoprotective enzymes thereby providing a protective response against CS-induced lung injury. We hypothesized that activating NRF2-dependent cytoprotective gene expression with sulforaphane (SFN) affords protection against CS-induced lung damage by inhibiting chemokine production. Results indicate that in the human BEAS-2B epithelial cell line, 5 μM SFN activated NRF2-dependent gene expression by triggering the translocation of NRF2 to the nucleus and significantly increased the expression of NRF2-dependent genes such as NADPH quinone oxidoreductase-1, heme oxygenase-1, and glutamate cysteine ligase modulatory subunit. Cigarette smoke extract (CSE) exposure of BEAS-2B cells significantly increased production of both IL-8 and MCP-1. Production of both chemokines was significantly reduced with SFN given prior to CSE; SFN inhibited IL-8 and MCP-1 gene expression at the transcription level. Our results indicate that activating NRF2 pathways with SFN inhibits CSE-induced chemokine production in human epithelial cells. However, the mechanism by which the production of chemokines is inhibited through SFN still remains to be elucidated. SFN may enhance NRF2 transcriptional activity resulting in the inhibition of proinflammatory pathways such

  8. Aspergillus antigen induces robust Th2 cytokine production, inflammation, airway hyperreactivity and fibrosis in the absence of MCP-1 or CCR2

    Directory of Open Access Journals (Sweden)

    Charo Israel F

    2004-09-01

    Full Text Available Abstract Background Asthma is characterized by type 2 T-helper cell (Th2 inflammation, goblet cell hyperplasia, airway hyperreactivity, and airway fibrosis. Monocyte chemoattractant protein-1 (MCP-1 or CCL2 and its receptor, CCR2, have been shown to play important roles in the development of Th2 inflammation. CCR2-deficient mice have been found to have altered inflammatory and physiologic responses in some models of experimental allergic asthma, but the role of CCR2 in contributing to inflammation and airway hyperreactivity appears to vary considerably between models. Furthermore, MCP-1-deficient mice have not previously been studied in models of experimental allergic asthma. Methods To test whether MCP-1 and CCR2 are each required for the development of experimental allergic asthma, we applied an Aspergillus antigen-induced model of Th2 cytokine-driven allergic asthma associated with airway fibrosis to mice deficient in either MCP-1 or CCR2. Previous studies with live Aspergillus conidia instilled into the lung revealed that MCP-1 and CCR2 play a role in anti-fungal responses; in contrast, we used a non-viable Aspergillus antigen preparation known to induce a robust eosinophilic inflammatory response. Results We found that wild-type C57BL/6 mice developed eosinophilic airway inflammation, goblet cell hyperplasia, airway hyperreactivity, elevations in serum IgE, and airway fibrosis in response to airway challenge with Aspergillus antigen. Surprisingly, mice deficient in either MCP-1 or CCR2 had responses to Aspergillus antigen similar to those seen in wild-type mice, including production of Th2 cytokines. Conclusion We conclude that robust Th2-mediated lung pathology can occur even in the complete absence of MCP-1 or CCR2.

  9. Genome-wide association replicates the association of Duffy antigen receptor for chemokines (DARC) polymorphisms with serum monocyte chemoattractant protein-1 (MCP-1) levels in Hispanic children.

    Science.gov (United States)

    Voruganti, V Saroja; Laston, Sandra; Haack, Karin; Mehta, Nitesh R; Smith, C Wayne; Cole, Shelley A; Butte, Nancy F; Comuzzie, Anthony G

    2012-12-01

    Obesity is associated with a chronic low inflammatory state characterized by elevated levels of chemokines. Monocyte chemoattractant protein-1 (MCP-1) is a member of the cysteine-cysteine (CC) chemokine family and is increased in obesity. The purpose of this study was to identify loci regulating serum MCP-1 in obese Hispanic children from the Viva La Familia Study. A genome-wide association (GWA) analysis was performed in 815 children, ages 4-19 years, using genotypes assayed with the Illumina HumanOmni1-Quad v1.0 BeadChips. All analyses were performed in SOLAR using a linear regression-based test under an additive model of allelic effect, while accounting for the relatedness of family members via a kinship variance component. The strongest association for MCP-1 levels was found with a non-synonymous single nucleotide polymorphism (SNP), rs12075, resulting in an amino acid substitution (Asp42Gly) in the Duffy antigen receptor for chemokines (DARC) gene product (minor allele frequency=43.6%, p=1.3 × 10(-21)) on chromosome 1. Four other DARC SNPs were also significantly associated with MCP-1 levels (p<10(-16)-10(-6)). The Asp42Gly variant was associated with higher levels of MCP-1 and accounted for approximately 10% of its variability. In addition, MCP-1 levels were significantly associated with SNPs in chemokine receptor 3 (CCR3) and caspase recruitment domain family, member 9 (CARD9). In summary, the association of the DARC Asp42Gly variant with MCP-1 levels replicates previous GWA results substantiating a potential role for DARC in the regulation of pro-inflammatory cytokines. PMID:23017229

  10. CCL8/MCP-2 is a target for mir-146a in HIV-1-infected human microglial cells

    OpenAIRE

    Rom, Slava; Rom, Inna; Passiatore, Giovanni; Pacifici, Marco; Radhakrishnan, Sujatha; Del Valle, Luis; Piña-Oviedo, Sergio; Khalili, Kamel; Eletto, Davide; Peruzzi, Francesca

    2010-01-01

    MicroRNA-mediated regulation of gene expression appears to be involved in a variety of cellular processes, including development, differentiation, proliferation, and apoptosis. Mir-146a is thought to be involved in the regulation of the innate immune response, and its expression is increased in tissues associated with chronic inflammation. Among the predicted gene targets for mir-146a, the chemokine CCL8/MCP-2 is a ligand for the CCR5 chemokine receptor and a potent inhibitor of CD4/CCR5-medi...

  11. Capillary fracture of soft gels.

    Science.gov (United States)

    Bostwick, Joshua B; Daniels, Karen E

    2013-10-01

    A liquid droplet resting on a soft gel substrate can deform that substrate to the point of material failure, whereby fractures develop on the gel surface that propagate outwards from the contact line in a starburst pattern. In this paper, we characterize (i) the initiation process, in which the number of arms in the starburst is controlled by the ratio of the surface tension contrast to the gel's elastic modulus, and (ii) the propagation dynamics showing that once fractures are initiated they propagate with a universal power law L[proportional]t(3/4). We develop a model for crack initiation by treating the gel as a linear elastic solid and computing the deformations within the substrate from the liquid-solid wetting forces. The elastic solution shows that both the location and the magnitude of the wetting forces are critical in providing a quantitative prediction for the number of fractures and, hence, an interpretation of the initiation of capillary fractures. This solution also reveals that the depth of the gel is an important factor in the fracture process, as it can help mitigate large surface tractions; this finding is confirmed with experiments. We then develop a model for crack propagation by considering the transport of an inviscid fluid into the fracture tip of an incompressible material and find that a simple energy-conservation argument can explain the observed material-independent power law. We compare predictions for both linear elastic and neo-Hookean solids, finding that the latter better explains the observed exponent. PMID:24229192

  12. Use of capillary electrophoresis and indirect detection to quantitate in-capillary enzyme-catalyzed microreactions.

    Science.gov (United States)

    Zhang, Y; el-Maghrabi, M R; Gomez, F A

    2000-04-01

    The use of capillary electrophoresis and indirect detection to quantify reaction products of in-capillary enzyme-catalyzed microreactions is described. Migrating in a capillary under conditions of electrophoresis, plugs of enzyme and substrate are injected and allowed to react. Capillary electrophoresis is subsequently used to measure the extent of reaction. This technique is demonstrated using two model systems: the conversion of fructose-1,6-bisphosphate to dihydroxyacetone phosphate and glyceraldehyde-3-phosphate by fructose-biphosphate aldolase (ALD, EC 4.1.2.13), and the conversion of fructose-1,6-bisphosphate to fructose-6-phosphate by fructose-1,6-bisphospatase (FBPase, EC 3.1.3.11). These procedures expand the use of the capillary as a microreactor and offer a new approach to analyzing enzyme-mediated reactions. PMID:10892022

  13. A Novel Polybrene/Chondroitin Sulfate C Double Coated Capillary and Its Application in Capillary Electrophoresis

    Institute of Scientific and Technical Information of China (English)

    DU,Ying-Xiang(杜迎翔); HONDA,Susumu; TAGA,Atsushi; LIU,Wen-Ying(刘文英); SUZUKI,Shigeo

    2002-01-01

    A new capillary coated by double polymer, polybrene/chondroitin sulfate C (P/CC), was developed using a simple procedure. The P/CC double coated capillary showed long lifetime,strong chemical stability and good reproducibility. It endured during more than 100 replicated analyses and was also tolerant to HCl (1 mol/L), NaOH (0.01 mol/L), CH3OH and CH3CN. The P/CC double coated capillary can be applied to basic drug analyses. The adsorption of basic drugs to the capillary wall was suppressed and the peak tailing greatly decreased. The use of the P/CC double coated capillary allowed excelent separation of the enantiomers of some basic drugs by using chondroitin sulfate C as the chiral selector, ami the peak symmetry of basic drugs was further improved under these conditions.

  14. Nanoparticle-based capillary electroseparation of proteins in polymer capillaries under physiological conditions

    DEFF Research Database (Denmark)

    Nilsson, C.; Harwigsson, I.; Becker, K.;

    2010-01-01

    of nanoparticles, i.e. in CE mode, the protein samples adsorbed completely to the capillary walls and could not be recovered. In contrast, nanoparticle-based capillary electroseparation resolved green fluorescent protein from several of its impurities within I min. Furthermore, a mixture of native green...... fluorescent protein and two of its single-amino-acid-substituted variants was separated within 2.5 min with efficiencies of 400 000 plates/m. The nanoparticles prevent adsorption by introducing a large interacting surface and by obstructing the attachment of the protein to the capillary wall. A one......Totally porous lipid-based liquid crystalline nanoparticles were used as pseudostationary phase for capillary electroseparation with LIF detection of proteins at physiological conditions using unmodified cyclic olefin copolymer capillaries (Topas (R), 6.7 cm effective length). In the absence...

  15. Capillary-Tube Model and Experiment of Multiphase Flow in Capillary Fringes

    Institute of Scientific and Technical Information of China (English)

    武晓峰; 唐杰; 吕贤弼

    2002-01-01

    Contamination of soil and groundwater by organic substances is causing more and more problems worldwide. Analysis of the movement and distribution of nonaqueous phase liquids (NAPLs) in subsurface domain is critical for contaminant remediation. Two-dimensional experiments were conducted in a transparent plexiglass trough (105.0 cm×70.0 cm×1.5 cm) to simulate the release and redistribution of gasoline and kerosene in porous media. The results show that before the contaminant distribution reaches equilibrium, the movement of light NAPLs (LNAPLs) can be divided into four sub-stages. After the contaminant front reaches the upper boundary of the capillary fringe, contaminant movement along the upper boundary of the capillary fringe is the primary transport process. Most of the contaminants then move into the capillary fringe except for the residual part. One-dimensional and two-dimensional capillary tube models were developed to analyze the movement of LNAPLs in the capillary fringe.

  16. Modifying alumina red mud to support a revegetation cover

    Science.gov (United States)

    Xenidis, A.; Harokopou, A. D.; Mylona, E.; Brofas, G.

    2005-02-01

    Alumina red mud, a fine-textured, iron-rich, alkaline residue, is the major waste product of bauxite digestion with caustic soda to remove alumina. The high alkalinity and salinity as well as the poor nutrient status are considered to be the major constraints of red mud revegetation. This research was conducted to evaluate the ameliorating effect of gypsum, sewage sludge, ferrous sulfate, ammonium sulfate, ammonium nitrate, and calcium phosphate on alumina red mud. The effectiveness of the mixtures was evaluated by applying extraction tests and performing experiments using six plant species. Gypsum amendment significantly reduced the pH, electrical conductivity, and sodium and aluminum content of red mud. Sewage sludge application had an extended effect in improving both the soil structure and the nutrient status of the gypsum-amended red mud. Together with the gypsum and sewage sludge, calcium phosphate application into red mud enhanced plant growth and gave the most promising results.

  17. Studies on synthesis of alumina nanopowder from synthetic Bayer liquor

    International Nuclear Information System (INIS)

    Procedure for synthesis of alumina nanopowder from Bayer liquor (synthetic sodium aluminate solution) is investigated. Cooling, ageing and then addition of 3 ml/l Tiron (1,2-dihydroxy-3,5-benzene disulfonic acid disodium salt) to the supersaturated liquor affect purity and fineness of the nanopowder product. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray (EDAX) analyses indicate that purity of the alumina nanopowder increases with the aging time. Experimental observations show that highly pure alumina nanopowders could be produced by direct calcination of cold gelatinous sodium aluminate solution followed by careful washing at a Tiron concentration of 3 ml/l NaOH

  18. Calculation of the effective emissivity of blackbodies made of alumina

    International Nuclear Information System (INIS)

    Blackbodies are sources of temperature radiation that are used for calibration of radiation thermometers. Their effective emissivity should be close to the value of 1 to approximate an ideal Planckian radiator. Their effective emissivity depends on the geometry of their cavity and the used material. It can be estimated by measurements, but often it is calculated by numerical methods. For typical graphite blackbodies, it was shown in the past that high effective emissivities better than 0.999 can be reached. In this paper, calculations of the effective emissivity of a alumina blackbody are presented. Alumina is a new material for blackbodies, with different radiation properties. Using two calculation methods (integrative cavity method and Monte Carlo method), the effective cavity emissivity for blank and coated alumina is estimated. It is shown that effective spectral emissivities up to 0.999 87 can be reached. (paper)

  19. Origin of High-Alumina Basalt, Andesite, and Dacite Magmas.

    Science.gov (United States)

    Hamilton, W

    1964-10-30

    The typical volcanic rocks of most island arcs and eugeosynclines, and of some continental environments, are basalt, andesite, and dacite, of high alumina content. The high-alumina basalt differs from tholeiitic basalt primarily in having a greater content of the components of calcic plagioclase. Laboratory data indicate that in the upper mantle, below the level at which the basaltic component of mantle rock is transformed by pressure to eclogite or pyroxenite, the entire basaltic portion probably is melted within a narrow temperature range, but that above the level of that transformation plagioclase is melted selectively before pyroxene over a wide temperature range. The broad spectrum of high-alumina magmas may represent widely varying degrees of partial melting above the transformation level, whereas narrow-spectrum tholeiite magma may represent more complete melting beneath it. PMID:17794034

  20. Thermal and Electrical Characterization of Alumina Substrate for Microelectronic Applications

    International Nuclear Information System (INIS)

    This paper reports the effect of sintering temperature on thermal and electrical properties of alumina material as substrate for microelectronic devices. Alumina materials in the form of green sheet with 1 mm thickness were sintered at 1100 deg. C, 1300 deg. C and 1500 deg. C for about 20 hours using heating and cooling rates of 2 deg. C/min. The densities were measured using densitometer and the microstructures of the samples were analyzed using SEM micrographs. Meanwhile thermal and electrical properties of the samples were measured using flash method and impedance analyzer respectively. It was found that thermal conductivity and thermal diffusivity of the substrate increases as sintering temperature increases. It was found also that the dielectric constant of alumina substrate increases as the sintering temperature increases.

  1. Pressureless sintering behavior of injection molded alumina ceramics

    Directory of Open Access Journals (Sweden)

    Liu W.

    2014-01-01

    Full Text Available The pressureless sintering behaviors of two widely used submicron alumina (MgOdoped and undoped with different solid loadings produced by injection molding have been studied systematically. Regardless of the sinterability of different powders depending on their inherent properties, solid loading plays a critical role on the sintering behavior of injection molded alumina, which greatly determines the densification and grain size, and leads to its full densification at low temperatures. As compared to the MgO-doped alumina powder, the undoped specimens exhibit a higher sinterability for its smaller particle size and larger surface area. While full densification could be achieved for MgO-doped powders with only a lower solid loading, due to the fact that MgO addition can reduce the detrimental effect of the large pore space on the pore-boundary separation.

  2. Alumina Template-Dependant Growth of Cobalt Nanowire Arrays

    Directory of Open Access Journals (Sweden)

    L. Malferrari

    2009-01-01

    Full Text Available Different electrochemical regimes and porous alumina were applied for template synthesis of cobalt nanowire (nw arrays, revealing several peculiar cases. In contrast to quite uniform filling of sulfuric acid alumina templates by alternating current deposition, nonuniform growth of the Co nw tufts and mushrooms was obtained for the case of oxalic acid templates. We showed herein for the first time that such configurations arise from the spontaneous growth of cobalt nw groups evolving from the cobalt balls at the Al/alumina interface. Nevertheless, the uniform growth of densely packed cobalt nw arrays, up to tens of micrometers in length, was obtained via long-term direct current galvanostatic deposition at low current density using oxalic acid templates one-side coated by conducting layer. The unique point of this regime is the formation of hexagonal lattice Co nws with a preferred (100 growth direction.

  3. Fabrication of alumina films with laminated structures by ac anodization

    International Nuclear Information System (INIS)

    Anodization techniques by alternating current (ac) are introduced in this review. By using ac anodization, laminated alumina films are fabricated. Different types of alumina films consisting of 50–200 nm layers were obtained by varying both the ac power supply and the electrolyte. The total film thickness increased with an increase in the total charge transferred. The thickness of the individual layers increased with the ac voltage; however, the anodization time had little effect on the film thickness. The laminated alumina films resembled the nacre structure of shells, and the different morphologies exhibited by bivalves and spiral shells could be replicated by controlling the rate of increase of the applied potentials. (paper)

  4. Intrinsic and extrinsic luminescence of nanosize transition alumina powders

    International Nuclear Information System (INIS)

    Luminescence spectroscopy in the VUV-visible range under electron-beam excitation and synchrotron radiation was applied to investigate electronic properties of alumina nanopowders, which were prepared using the combustion synthesis method. By varying reaction and post treatment conditions we were able to prepare phase pure samples and powders with mixtures of α- and γ-phases mainly. In addition to the well-known 7.6 eV luminescence of STE of α-alumina, all samples possessed complex emission bands in UV range (3–5 eV) which originate from intrinsic excitonic emissions and extrinsic electronic excitations. -- Highlights: ► Luminescent spectroscopy of nanosized alumina powders was studied at 8 K. ► The crystalline structure of samples was analysed. ► Luminescent spectra, lifetimes and absorption onsets were discussed

  5. Plastic deformation and sintering of alumina under high pressure

    International Nuclear Information System (INIS)

    Plastic deformation of alumina (Al2O3) under high pressure was investigated by observing the shape changes of spherical particles, and the near fully dense transparent bulks were prepared at around 5.5 GPa and 900 °C. Through analyzing the deformation features, densities, and residual micro-strain of the Al2O3 compacts prepared under high pressures and temperatures (2.0–5.5 GPa and 600–1200 °C), the effects of plastic deformation on the sintering behavior of alumina have been demonstrated. Under compression, the microscopic deviatoric stress caused by grain-to-grain contact could initiate the plastic deformation of individual particles, eliminate pores of the polycrystalline samples, and enhance the local atomic diffusion at the grain boundaries, thus produced transparent alumina bulks

  6. Alumina composites for oxide/oxide fibrous monoliths

    International Nuclear Information System (INIS)

    Most work on ceramic fibrous monoliths (FMs) has focused on the Si3N4/BN system. In an effort to develop oxidation-resistant FMs, several oxide systems have recently been examined. Zirconia-toughened alumina and alumina/mullite appear to be good candidates for the cell phase of FMs. These composites offer higher strength and toughness than pure alumina and good high-temperature stability. By combining these oxides, possibly with a weaker high-temperature oxide as the cell-boundary phase, it should be possible to product a strong, resilient FM that exhibits graceful failure. Several material combinations have been examined. Results on FM fabrication and microstructural development are presented

  7. Effects of yttrium on the sintering and microstructure of alumina-silicon carbide "nanocomposites"

    OpenAIRE

    Cock, AM; Shapiro, IP; Todd, RI; Roberts, SG

    2005-01-01

    Alumina and alumina-based "nanocomposites" with 2 and 5 vol% silicon carbide and varying amounts of yttria (0-1.5 wt%) have been prepared by pressureless sintering in the temperature range 1450°-1650°C. The effects of composition and sintering temperature on density and microstructure are reported. Yttria inhibited sintering in alumina, but enhanced the sinterability of the nanocomposites. It also induced abnormal grain growth in both alumina and nanocomposites, but strongly bimodal grain siz...

  8. Hydrogen removal from e-beam deposited alumina thin films by oxygen ion beam

    International Nuclear Information System (INIS)

    Hydrogen interstitials and oxygen vacancies defects create energy levels in the band gap of alumina. This limits the application of alumina as a high-k dielectric. A low thermal budget method for removal of hydrogen from alumina is discussed. It is shown that bombardment of alumina films with low energy oxygen ion beam during electron beam evaporation deposition decreases the hydrogen concentration in the film significantly

  9. Differential gene expression during capillary morphogenesis in a microcarrier-based three-dimensional in vitro model of angiogenesis with focus on chemokines and chemokine receptors

    Institute of Scientific and Technical Information of China (English)

    Xi-Tai Sun; Min-Yue Zhang; Chang Shu; Qiang Li; Xiao-Gui Yan; Ni Cheng; Yu-Dong Qiu; Yi-Tao Ding

    2005-01-01

    AIM: To globally compare the gene expression profiles during the capillary morphogenesis of human microvascular endothelial cells (HMVECs) in an in vitro angiogenesis system with affymetrix oligonucleotide array.METHODS: A microcarrier-based in vitro angiogenesis system was developed, in which ECs migrated into the matrix,proliferated, and formed capillary sprouts. The sprouts elongated, branched and formed networks. The total RNA samples from the HMVECs at the selected time points (0.5,24, and 72 h) during the capillary morphogenesis were used for microarray analyses, and the data were processed with the softwares provided by the manufacturers. The expression patterns of some genes were validated and confirmed by semi-quantitative RT-PCR. The regulated genes were grouped based on their molecular functions and expression patterns, and among them the expression of chemokines and chemokine receptors was specially examined and their functional implications were analyzed.RESULTS: A total of 1 961 genes were up- or downregulated two-folds or above, and among them, 468 genes were up- or down-regulated three-folds or above. The regulated genes could be grouped into categories based on their molecular functions, and were also clustered into six groups based on their patterns of expression. As for chemokines and chemokine receptors, CXCL1/GRO-α,CXCL2/GRO-β, CXCLS/ENA-78, CXCL6/GCP2, IL-8/CXCL8,CXCL12/SDF-1, CXCL9/Mig, CXC11/ITAC, CX3CL1/fractalkine,CCL2/MCP-1, CCL3, CCLS/RANTES, CCL7, CCL15, CCL21,CCL23, CCL28, and CCR1, CCR9, CXCR4 were identified.Moreover, these genes demonstrated different changing patterns during the capillary morphogenesis, which implied that they might have different roles in the sequential process. Among the chemokines identified, CCL2/MCP-1,CCL5/RANTES and CX3CL1 were specially up-regulated at the 24-h time point when the sprouting characterized the morphological change. It was thus suggested that they might exert crucial roles at the early stage

  10. The capillary hysteresis model HYSTR: User's guide

    International Nuclear Information System (INIS)

    The potential disposal of nuclear waste in the unsaturated zone at Yucca Mountain, Nevada, has generated increased interest in the study of fluid flow through unsaturated media. In the near future, large-scale field tests will be conducted at the Yucca Mountain site, and work is now being done to design and analyze these tests. As part of these efforts a capillary hysteresis model has been developed. A computer program to calculate the hysteretic relationship between capillary pressure φ and liquid saturation (S1) has been written that is designed to be easily incorporated into any numerical unsaturated flow simulator that computes capillary pressure as a function of liquid saturation. This report gives a detailed description of the model along with information on how it can be interfaced with a transport code. Although the model was developed specifically for calculations related to nuclear waste disposal, it should be applicable to any capillary hysteresis problem for which the secondary and higher order scanning curves can be approximated from the first order scanning curves. HYSTR is a set of subroutines to calculate capillary pressure for a given liquid saturation under hysteretic conditions

  11. Synthetic Capillaries to Control Microscopic Blood Flow

    Science.gov (United States)

    Sarveswaran, K.; Kurz, V.; Dong, Z.; Tanaka, T.; Penny, S.; Timp, G.

    2016-02-01

    Capillaries pervade human physiology. The mean intercapillary distance is only about 100 μm in human tissue, which indicates the extent of nutrient diffusion. In engineered tissue the lack of capillaries, along with the associated perfusion, is problematic because it leads to hypoxic stress and necrosis. However, a capillary is not easy to engineer due to its complex cytoarchitecture. Here, it is shown that it is possible to create in vitro, in about 30 min, a tubular microenvironment with an elastic modulus and porosity consistent with human tissue that functionally mimicks a bona fide capillary using “live cell lithography”(LCL) to control the type and position of cells on a composite hydrogel scaffold. Furthermore, it is established that these constructs support the forces associated with blood flow, and produce nutrient gradients similar to those measured in vivo. With LCL, capillaries can be constructed with single cell precision—no other method for tissue engineering offers such precision. Since the time required for assembly scales with the number of cells, this method is likely to be adapted first to create minimal functional units of human tissue that constitute organs, consisting of a heterogeneous population of 100-1000 cells, organized hierarchically to express a predictable function.

  12. EUV radiation from nitrogen capillary discharge

    Science.gov (United States)

    Frolov, Oleksandr; Kolacek, Karel; Schmidt, Jiri; Straus, Jaroslav

    2014-08-01

    In the last decade EUV sources attract interest from researchers over the world. One of the main motivations is EUV lithography, which could lead to further miniaturization in electronics. Nitrogen recombination laser at wavelength of 13.4 nm based on capillary discharge Z-pinch configuration could be used in experiments with testing of resolution of photoresist for EUV lithography (close to wavelength of 13.5 nm Si/Mo multilayer mirrors have a high reflectivity at normal incidence angles). In this work, pinching of nitrogen-filled capillary discharge is studied for the development of EUV laser, which is based on recombination pumping scheme. The goal of this study is achieving the required plasma conditions using a capillary discharge Z-pinch apparatus. In experiments with nitrogen, the capillary length was shortened from 232 mm to 90 mm and current quarter-period was changed from 60 ns to 50 ns in contrast with early experiments with Ne-like argon laser. EUV radiation from capillary discharge was registered by X-ray vacuum diode for different pressure, amplitude and duration of pre-pulse and charging voltage of the Marx generator.

  13. Direct current plasma spraying of mechanofused alumina-steel particles

    OpenAIRE

    Bouneder, Mohamed; Ageorges, Hélène; El Ganaoui, M.; Pateyron, Bernard; Fauchais, Pierre

    2009-01-01

    Paper project pages 26 Stainless steel particles (60 µm in mean diameter) cladded with an alumina shell (2 µm thick and manufactured by mechanofusion) were sprayed with an Ar-H2 (53-7 slm) d.c. plasma jet (I = 500 A, P = 28 kW, \\rho_th = 56 %). Two main types of particles were collected in flight, as close as 50 mm downstream of the nozzle exit: particles with a steel core with pieces of alumina unevenly distributed at their surface and those consisting of a spherical stainless steel parti...

  14. Behaviour modelling of two aluminas in divergent spherical pyrotechnical experiments

    International Nuclear Information System (INIS)

    Two pure aluminas of different characteristics have been subjected to the propagation of a longitudinal divergent spherical shock wave through pyrotechnical experiments. An approach combining a phenomenological analysis and numerical 1D-calculations is proposed to study the behaviour of these aluminas submitted to that type of wave loading. The modelling, proposed in a previous paper, is refined and gives satisfying experimentation-calculation correlations. An analysis of the influence exerted by the various encountered phenomena (plastic activity, pore closure, microcracking) is performed. The significant consequence of the activation of damage with an extension criterion is also underlined. (orig.)

  15. Inelastic neutron scattering studies of methyl chloride synthesis over alumina

    OpenAIRE

    Lennon, David; Parker, Stewart F.

    2014-01-01

    Not only is alumina the most widely used catalyst support material in the world, it is also an important catalyst in its own right. One major chemical process that uses alumina in this respect is the industrial production of methyl chloride. This is a large scale process (650 000 metric tons in 2010 in the United States), and a key feedstock in the production of silicones that are widely used as household sealants. In this Account, we show how, in partnership with conventional spectroscopic a...

  16. Comparative study on sintered alumina for ballistic shielding application

    International Nuclear Information System (INIS)

    This work presents a development of the armor made from special ceramic materials and kevlar. An experimental investigation was conducted to study the ballistic penetration resistance on three samples taken from sintered alumina: a commercial one and two formulations A and B made in IAE/CTA. The main differences between the two formulations was the grain size and bend resistance. The knowledge of the mechanisms during the penetration and perforation process allowed to apply a ductile composite laminate made form kevlar under the alumina to delay its rupture. The last ballistic test showed how a Weibull's modulii and other mechanical properties are able to improve ballistic penetration resistance. (author)

  17. Synthesis of alumina based on industrial waste material

    OpenAIRE

    López-Andrés, Sol; Fillali, Laila; Jiménez, José Antonio; Tayibi, Hanan; Padilla, Isabel; López-Delgado, Aurora

    2011-01-01

    A hazardous waste generated in slag milling process by the aluminium industry was used as a raw material for the synthesis of alumina, α-Al2O3. This waste is considered as hazardous material in the European legislation due to the release of toxic gases (hydrogen, ammonia, methane and hydrogen sulphide) in the presence of water. The process developed in this work allows to obtaining 1 ton of alumina from 4 tons of hazardous waste and generates an inert solid residue consisting principally of s...

  18. CRACK PROPAGATION BEHAVIOR AND LIFETIME PREDICTION IN ALUMINA AND ZIRCONIA

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The lifetime prediction of ceramics is discussed on the basis of the relationship between stress intensity factor KI and crack velocity v. The effects of water environment, the cyclic loading and microstructure of material on KI-v characteristics are studied by carrying out the crack growth tests by the double torsion (DT) method under the static and cyclic loading in both environments of air and water for alumina and zirconia. KI-v characteristics determined by the double torsion method are used to predict time-to-failure under the cyclic loading of alumina and zirconia ceramics. The predictions agree qualitatively with the experimental results.

  19. Adsorption of textile dye onto modified immobilized activated alumina

    OpenAIRE

    Ayesha Wasti; M. Ali Awan

    2016-01-01

    The study describes the synthesis of modified immobilized activated alumina (MIAA) and its application for the removal of textile dye from aqueous media. Immobilization was carried out by using the sol–gel method while modifications were made during the synthesis by adding powder activated alumina. Batch adsorption experiments were carried out at 20 ± 1 °C to see the effect of different parameters like contact time, stirring rate, initial concentration of the dye and dose of MIAA. The removal...

  20. Human monocyte-derived dendritic cells expressing both chemotactic cytokines IL-8, MCP-1, RANTES and their receptors,and their selective migration to these chemokines

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To characterize the mRNA expression of CXC chemokine IL-8, CC chemokine monocyte chemothractant protein-1 (MCP-1) and regulated on activation,normal T cell expressed and secreted (RANTES), and a newly defined DC chemokine DC- CK1 as well as the expression of IL-8 receptor, MCP-1 receptor and RANTES receptor in human monocyte derived dendritic cells (MoDCs).The migratory responsiveness of MoDC to IL-8, MCP-1 and RANTES was alsso studied. Methods In vitro generated MoDCs were obtained by differentiating monocytes in the presence of GM-CSF and IL-4 for 5 days. The time course of RNA expression was analyzed by RT-PCR and migratoly ability was assessed by a micromultiwell chemotaxis chamber assay. Results IL-8, MCP-1, RANTES and their corres ponding receptors were consistently expressed in MoDCs. DC-CK-1 expression was detectable efter 48 hours of differentiation. MoDC selectively migrated in response to MCP-1 and RANTES but not to IL-8 though transcripts of IL-8 receptor were present. Conclusion Because the capacity of dendritic cells to initiate immune responses depends on their specialized migratory and tissue homing properties, the expression of chemokines and their receptors along with the migratory responsiveness to chemokines of MoDC in our study suggests a potential role of chemokines in the interaction between dendritic cells and T cells and the induction of immune responses.

  1. Effect of PKC-β Signaling Pathway on Expression of MCP-1 and VCAM-1 in Different Cell Models in Response to Advanced Glycation End Products (AGEs

    Directory of Open Access Journals (Sweden)

    Lisienny C. T. Rempel

    2015-05-01

    Full Text Available Advanced glycation end products (AGEs are compounds classified as uremic toxins in patients with chronic kidney disease that have several pro-inflammatory effects and are implicated in the development of cardiovascular diseases. To explore the mechanisms of AGEs–endothelium interactions through the receptor for AGEs (RAGE in the PKC-β pathway, we evaluated the production of MCP-1 and VCAM-1 in human endothelial cells (HUVECs, monocytes, and a coculture of both. AGEs were prepared by albumin glycation and characterized by absorbance and electrophoresis. The effect of AGEs on cell viability was assessed with an MTT assay. The cells were also treated with AGEs with and without a PKC-β inhibitor. MCP-1 and VCAM-1 in the cell supernatants were estimated by ELISA, and RAGE was evaluated by immunocytochemistry. AGEs exposure did not affect cell viability, but AGEs induced RAGE, MCP-1, and VCAM-1 expression in HUVECs. When HUVECs or monocytes were incubated with AGEs and a PKC-β inhibitor, MCP-1 and VCAM-1 expression significantly decreased. However, in the coculture, exposure to AGEs and a PKC-β inhibitor produced no significant effect. This study demonstrates, in vitro, the regulatory mechanisms involved in MCP-1 production in three cellular models and VCAM-1 production in HUVECs, and thus mimics the endothelial dysfunction caused by AGEs in early atherosclerosis. Such mechanisms could serve as therapeutic targets to reduce the harmful effects of AGEs in patients with chronic kidney disease.

  2. Pengaruh Temperatur Bath Terhadap Alumina Solubility Pada Tungku Reduksi Di PT Inalum Kuala Tanjung

    OpenAIRE

    Rahman, Syahri

    2010-01-01

    Alumina solubility is maximum aluminium oxide concentration of the cryolite electrolyte depend on its composition. The factors that affect to the quantity of alumina solubility are cryolite temperature (NA3AlF6), %AlF3, and %CaF2 in cryolite. From observation data, know that if cryolite temperature high, so alumina solubility provided high too.

  3. PEG-albumin plasma expansion increases expression of MCP-1 evidencing increased circulatory wall shear stress: an experimental study.

    Directory of Open Access Journals (Sweden)

    C Makena Hightower

    Full Text Available Treatment of blood loss with plasma expanders lowers blood viscosity, increasing cardiac output. However, increased flow velocity by conventional plasma expanders does not compensate for decreased viscosity in maintaining vessel wall shear stress (WSS, decreasing endothelial nitric oxide (NO production. A new type of plasma expander using polyethylene glycol conjugate albumin (PEG-Alb causes supra-perfusion when used in extreme hemodilution and is effective in treating hemorrhagic shock, although it is minimally viscogenic. An acute 40% hemodilution/exchange-transfusion protocol was used to compare 4% PEG-Alb to Ringer's lactate, Dextran 70 kDa and 6% Hetastarch (670 kDa in unanesthetized CD-1 mice. Serum cytokine analysis showed that PEG-Alb elevates monocyte chemotactic protein-1 (MCP-1, a member of a small inducible gene family, as well as expression of MIP-1α, and MIP-2. MCP-1 is specific to increased WSS. Given the direct link between increased WSS and production of NO, the beneficial resuscitation effects due to PEG-Alb plasma expansion appear to be due to increased WSS through increased perfusion and blood flow rather than blood viscosity.

  4. TNF-{alpha} similarly induces IL-6 and MCP-1 in fibroblasts from colorectal liver metastases and normal liver fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Lars, E-mail: lars.mueller@uksh-kiel.de [Department of General and Thoracic Surgery, University Hospital of Schleswig-Holstein (Germany); Seggern, Lena von [Department of Hepatobiliary Surgery and Solid Organ Transplantation, University Hospital Hamburg-Eppendorf, Hamburg (Germany); Schumacher, Jennifer; Goumas, Freya; Wilms, Christian; Braun, Felix; Broering, Dieter C. [Department of General and Thoracic Surgery, University Hospital of Schleswig-Holstein (Germany)

    2010-07-02

    Cancer-associated fibroblasts (CAFs) represent the predominant cell type of the neoplastic stroma of solid tumors, yet their biology and functional specificity for cancer pathogenesis remain unclear. We show here that primary CAFs from colorectal liver metastases express several inflammatory, tumor-enhancing factors, including interleukin (IL)-6 and monocyte-chemoattractant protein (MCP)-1. Both molecules were intensely induced by TNF-{alpha} on the transcript and protein level, whereas PDGF-BB, TGF-{beta}1 and EGF showed no significant effects. To verify their potential specialization for metastasis progression, CAFs were compared to fibroblasts from non-tumor liver tissue. Interestingly, these liver fibroblasts (LFs) displayed similar functions. Further analyses revealed a comparable up-regulation of intercellular adhesion molecule-1 (ICAM-1) by TNF-{alpha}, and of alpha-smooth muscle actin, by TGF-{beta}1. Moreover, the proliferation of both cell types was induced by PDGF-BB, and CAFs and LFs displayed an equivalent migration towards HT29 colon cancer cells in Boyden chamber assays. In conclusion, colorectal liver metastasis may be supported by CAFs and resident fibroblastic cells competent to generate a prometastatic microenvironment through inflammatory activation of IL-6 and MCP-1.

  5. Association of MCP-1-2518A/G polymorphism with uveitis susceptibility: a Meta-analysis%MCP-1基因-2518A/G多态性与葡萄膜炎易感性的Meta分析

    Institute of Scientific and Technical Information of China (English)

    张小玲; 冀垒兵; 高晓唯; 肖云; 章玮; 张燕

    2015-01-01

    Background Monocyte chemoattractant protein-1 (MCP-1) polymorphisms are demonstrated to be significantly associated with the susceptibility to uveitis in recent years,while a consistent conclusion for the association of MCP-1-2518A/G polymorphism and uveitis risk is not reached yet.Objective This study was to comprehensively investigate the correlation between MCP-1-2518A/G polymorphism and uveitis susceptibility.Methods General searches of electronic database including PubMed,Embase,Web of Science,CNKI,VIP,Wanfang database and China biomedical literature database (CBD) were performed to retrieve published case-control studies regarding the association between MCP-1-2518A/G polymorphism and uveitis risk.The data were screened according to the inclusion and exclusion criteria and extracted,and the quality of included studies was evaluated.The pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated.Publication bias and sensitivity analysis were also assessed.All statistical analyses were conducted with RevMan 5.2 and Stata 12.0 software.Results A total of 8 eligible case-control studies involving 1 197 cases and 1 570 controls were included in the Meta-analysis.The results showed no significant association of MCP-1-2518A/G polymorphism with uveitis susceptibility in the G vs.A,GG vs.AA and GG vs.AG+AA models (all at P>0.05).MCP-1-2518A/G polymorphism was found to be significantly associated with uveitis risk in the GG+AG vs.AA model (P =0.01,OR =1.25,95% CI:1.06-1.48),while no significant association was found by the sensitive analysis (GG + AG vs.AA:P =0.19,OR =1.16,95% CI:0.93-1.45).The subgroup analysis by uveitis types revealed that the individuals carrying allele-G or GG genotype harbored a significantly increased risk for anterior uveitis (G vs.A:P=0.01,OR=1.49,95% CI:1.16-1.90;GG vs.AA:P=0.01,OR=2.09,95% CI:1.21-3.61;GG+AG vs.AA:P=0.01,OR=1.58,95% CI:1.12-2.23;GG vs.AG+AA:P=0.01,OR=1.78,95% CI:1.12-2.83).The individuals with

  6. Novel absorption detection techniques for capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Y.

    1994-07-27

    Capillary electrophoresis (CE) has emerged as one of the most versatile separation methods. However, efficient separation is not sufficient unless coupled to adequate detection. The narrow inner diameter (I.D.) of the capillary column raises a big challenge to detection methods. For UV-vis absorption detection, the concentration sensitivity is only at the {mu}M level. Most commercial CE instruments are equipped with incoherent UV-vis lamps. Low-brightness, instability and inefficient coupling of the light source with the capillary limit the further improvement of UV-vis absorption detection in CE. The goals of this research have been to show the utility of laser-based absorption detection. The approaches involve: on-column double-beam laser absorption detection and its application to the detection of small ions and proteins, and absorption detection with the bubble-shaped flow cell.

  7. Capillary filling in closed end nanochannels.

    Science.gov (United States)

    Phan, Vinh Nguyen; Nguyen, Nam-Trung; Yang, Chun; Joseph, Pierre; Djeghlaf, Lyes; Bourrier, David; Gue, Anne-Marie

    2010-08-17

    We investigated the interactions between liquid, gas, and solid phases in the capillary filling process of closed-end nanochannels. This paper presents theoretical models without and with absorption and diffusion of gas molecules in the liquid. Capillary filling experiments were carried out in closed-end silicon nanochannels with different lengths. The theoretical and measured characteristics of filling length versus time are compared. The results show that the filling process consists of two stages. The first stage resembles the capillary filling process in an open-end nanochannel. However, a remarkable discrepancy between the experimental results and the theory without gas absorption is observed in the second stage. A closer investigation of the second stage reveals that the dissolution of gas in the liquid is important and can be explained by the model with gas absorption and diffusion. PMID:20695566

  8. Catalytic cleavage of lignin b-O-4 link mimics using copper on alumina and magnesia-alumina

    OpenAIRE

    Strassberger, Z.; Alberts, A.H.; Louwerse, M.J.; Tanase, S.; Rothenberg, G.

    2013-01-01

    Copper on γ-alumina and on mixed magnesia-alumina, Cu/MgO-Al2O3, catalyse the hydrodeoxygenation (HDO) of β-O-4 lignin-type dimers, giving valuable aromatics. The typical selectivity to phenol is as high as 20%. By changing the support's acidity we can modify the dispersion of copper. Interestingly, more HDO occurs with larger copper agglomerates than with finely dispersed particles. The presence of copper also increases the selectivity of the HDO cleavage. Three different pathways are hypoth...

  9. Capillary interactions in nano-particle suspensions

    International Nuclear Information System (INIS)

    We have investigated the structures formed by colloidal particles suspended in solvents at volume fractions below 10% and interacting through capillary bridges. Such systems resemble colloidal gas of sticky nano-spheres that form pearl-necklace like chains that, in turn, induce strong viscoelasticity due to the formation of 3-D fractal network. The capillary force dominates the electrostatic and Van der Waals forces in solutions and can bridge multiple particles depending of the volume of the capillary bridge. We have investigated the morphology of the structures formed at different fractions of the bridging fluid. Small-angle neutron scattering (SANS) is used to study nanoparticles with an average diameter of 10 nm in polar and non-polar organic solvents at ambient temperatures. SANS intensity as a function of the scattering vector is analyzed as a product of a form factor, that depends on the particle shape, and a structure factor, that characterizes the interparticle inter reactions. The interaction of particles in polar solvents is considered to be through electrostatic repulsion and the data is successfully fitted by Hayter-Penfold mean spherical approximation (HPMSA). Computer simulations of a pearl necklace-like chain of spheres is conducted to explain the structure factor when capillary bridges are present. Alternatively, we have analyzed the slope of the intensity at low scattering vector in a double logarithmic plot to determine the dimension of the fractal structures formed by the particles at different volume fraction of the bridging fluid. We have also studied the properties of the capillary bridge between a pair of particles. The significance of this study is to explore the possibility of using capillary force as a tool to engineer new colloidal structures and materials in solutions and to optimize their viscoelastic properties. (author)

  10. Capillary Rise of Liquids in Nanopores

    CERN Document Server

    Huber, Patrick; Kityk, Andriy V

    2006-01-01

    We present measurements on the spontaneous imbibition (capillary rise) of water, a linear hydrocarbon (n-C16H34) and a liquid crystal (8OCB) into the pore space of monolithic, nanoporous Vycor glass (mean pore radius 5 nm). Measurements on the mass uptake of the porous hosts as a function of time, m(t), are in good agreement with the Lucas-Washburn square root of time prediction, typical of imbibition of liquids into porous hosts. The relative capillary rise velocities scale as expected from the bulk fluid parameters.

  11. A lymph nodal capillary-cavernous hemangioma.

    Science.gov (United States)

    Dellachà, A; Fulcheri, E; Campisi, C

    1999-09-01

    A capillary-cavernous hemangioma in an obturator lymph node was found incidentally in a 64 year-old woman who had undergone unilateral salpingo-oophorectomy and lymphadenectomy for an ovarian neoplasm. Vascular tumors of lymph nodes are briefly reviewed including eight previously described nodal capillary-cavernous hemangiomas. The association with other splanchnic hemangiomas is pointed out and the likelihood that the lesion is a hamartoma rather than a true neoplasm is addressed. Despite its rarity, this entity needs to be recognized by lymphologists who image lymph nodes by lymphangiography as well as by lymph nodal pathologists. PMID:10494525

  12. Intracerebral Capillary Hemangioma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Youn, In Young; Kim, Jae Kyun; Byun, Jun Soo [Dept. of Radiology, Chung Ang University Medical Center, Chung Ang University College of Medicine, Seoul (Korea, Republic of); Park, Eon Sub [Dept. of Radiology, Chung Ang University Medical Center, Chung Ang University College of Medicine, Seoul (Korea, Republic of)

    2012-01-15

    Intracerebral capillary hemangiomas are very rare benign vascular tumors that mostly occur during infancy. We described a 69-year-old man with generalized tonic-clonic seizures who was diagnosed with an intracranial mass. Multidetector computed tomography, magnetic resonance imaging and digital subtraction angiography studies were performed for evaluation of brain, and there was a well-enhancing mass found in the right temporal lobe without a definite feeding vessel. The patient underwent surgery and the pathologic examination demonstrated marked proliferation of small vessels with a lobular pattern in the brain parenchyma, which was confirmed to be capillary hemangioma.

  13. Microfluidic chip-capillary electrophoresis devices

    CERN Document Server

    Fung, Ying Sing; Du, Fuying; Guo, Wenpeng; Ma, Tongmei; Nie, Zhou; Sun, Hui; Wu, Ruige; Zhao, Wenfeng

    2015-01-01

    Capillary electrophoresis (CE) and microfluidic chip (MC) devices are relatively mature technologies, but this book demonstrates how they can be integrated into a single, revolutionary device that can provide on-site analysis of samples when laboratory services are unavailable. By introducing the combination of CE and MC technology, Microfluidic Chip-Capillary Electrophoresis Devices broadens the scope of chemical analysis, particularly in the biomedical, food, and environmental sciences.The book gives an overview of the development of MC and CE technology as well as technology that now allows

  14. TESTICULAR CAPILLARY HEMANGIOMA: DESCRIPTION OF A CASE

    Directory of Open Access Journals (Sweden)

    A. S. Markova

    2014-07-01

    Full Text Available The paper describes a clinical case of testicular capillary hemangioma in a 24-year-old man undergone a partial resection of the testis with the intraoperative morphological examination. Testicular capillary hemangioma is a rare benign tumor of a vascular origin, which can be similar to malignant testicular tumors on the clinical presentation, as well as on the imaging methods, in particular to seminoma. The intraoperative histological study can assist in avoiding organ-removing surgical interventions in diagnostically ambiguous cases if a benign testicular tumor is diagnosed.

  15. The relationship of urinary MCP1、 fetuin-A expression and urinary MDA in patients with nephrolithiasis%肾结石患者尿液MCP-1、胎球蛋白-A表达与MDA的关系

    Institute of Scientific and Technical Information of China (English)

    孙春

    2015-01-01

    目的:探讨肾结石患者尿液炎症细胞因子变化以及氧化应激在结石形成中的作用.方法:选择75例草酸钙结石住院患者,随机挑选25例健康人作正常对照组.收集两组人的晨尿,分别运用ELLISA法和TBA法检测尿液中单核细胞趋化蛋白(MCP-1)、胎球蛋白-A (Fetuin-A)及丙二醛(MDA)的含量.结果:MCP-1在结石组含量为212.45 (59.24,673.50)pg/mg cr,在对照组为74.36(22.45,203.57)pg/mg cr,结石组高于对照组(P<0.05);胎球蛋白-A在结石组为320.80(42.28,1819.85)ng/mg cr,在对照组为787.94(187.03,3269.17)ng/mg cr,结石组低于对照组(P<0.05);MDA在结石组高于正常对照组(P<0.05).相关性分析:结石组尿液MCP-1和MDA不相关,r=0.045,P> 0.05;胎球蛋白-A和MDA不相关,r=-0.016,P> 0.05.结论:尿液炎症细胞因子变化和氧化应激损伤可能在肾结石形成中起作用,但是氧化应激损伤可能未参与尿液炎症细胞因子的调节.

  16. Citrus auraptene acts as an agonist for PPARs and enhances adiponectin production and MCP-1 reduction in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Citrus fruit compounds have many health-enhancing effects. In this study, using a luciferase ligand assay system, we showed that citrus auraptene activates peroxisome proliferator-activated receptor (PPAR)-α and PPARγ. Auraptene induced up-regulation of adiponectin expression and increased the ratio of the amount of high-molecular-weight multimers of adiponectin to the total adiponectin. In contrast, auraptene suppressed monocyte chemoattractant protein (MCP)-1 expression in 3T3-L1 adipocytes. Experiments using PPARγ antagonist demonstrated that these effects on regulation of adiponectin and MCP-1 expression were caused by PPARγ activations. The results indicate that auraptene activates PPARγ in adipocytes to control adipocytekines such as adiponectin and MCP-1 and suggest that the consumption of citrus fruits, which contain auraptene can lead to a partial prevention of lipid and glucose metabolism abnormalities

  17. Storage of strawberries (Fragaria ananassa L. cv. ‘Oso Grande’, subjected to 1-MCP - doi: 10.4025/actascitechnol.v34i3.8790

    Directory of Open Access Journals (Sweden)

    Polyanna Alves Silva

    2012-05-01

    Full Text Available This study aimed to investigate the influence of 1 - methylcyclopropene (1-MCP on the substances involved in the softening of strawberry, cultivar Oso Grande, stored at room temperature, from the municipality of Itutinga, State of Minas Gerais. The parameters evaluated were: firmness, total pectin, percentage of solubilization, activities of the enzymes pectinmethylesterase (PME (EC 3.1.1.11 and polygalacturonase (PG (EC 3.2.1.15. It was concluded that 1-MCP delayed the softening of the fruits, since the fruits that were treated with 1-MCP after storage, have shown greater firmness, lower activities of PG and PME, and lower contents of total pectin, soluble pectin and percentage of solubilization. 

  18. Quantification of nucleotides by ICPMS: coupling of ICPMS with capillary electrophoresis or capillary HPLC

    International Nuclear Information System (INIS)

    Full text: Quantification of nucleotides in small volumes of biological samples has eagerly been demanded. A method using ICPMS coupled with capillary electrophoresis or capillary liquid chromatography is reported. A new interface system, which consists of a double tube nebulizer inserted with a fused silica capillary tube and a cylinder mini-chamber with a sheath gas inlet, was designed. Moreover, the surface conditions of the sampling and skimmer cones, and the introduction of H2 gas into the plasma were found to significantly improve the signal/background ratio for phosphorus determination at m/z 31. (author)

  19. Substrate-induced coagulation (SIC) of nano-disperse alumina in non-aqueous media: The dispersibility and stability of alumina in N-methyl-2-pyrrolidinone

    OpenAIRE

    Basch, Angelika; Strnad, Simona

    2011-01-01

    This work investigated colloidal properties such as the zeta-potential, the electrophoretic mobilities and the wetting behaviour of alumina dispersed in non-aqueous media. Non-aqueous dispersions of alumina were prepared in the solvent N-methyl-2-pyrrolidinone (NMP). The wetting behaviour of alumina in NMP was characterized by the powder contact angle method and the Wilhemy plate method. The behaviour of the dispersion should provide information for the development of a substrate-induced coag...

  20. Viscosity measurement in the capillary tube viscometer under unsteady flow

    International Nuclear Information System (INIS)

    The objective of the present study is to develop a new device that the viscous characteristics of fluids are determined by applying the unsteady flow concept to the traditional capillary tube viscometer. The capillary tube viscometer consists of a small cylindrical reservoir, capillary tube, a load cell system that measures the mass flow rate, interfaces, and computer. Due to the small size of the reservoir the height of liquid in the reservoir decreases as soon as the liquid in the reservoir drains out through the capillary and the mass flow rate in the capillary decreases as the hydrostatic pressure in the reservoir decreases resulting in a decrease of the shear rate in the capillary tube. The instantaneous shear rate and driving force in the capillary tube are determined by measuring the mass flow rate through the capillary, and the fluid viscosity is determined from the measured flow rate and the driving force

  1. A Rare Association of Trigeminal Autonomic Cephalgia: Pontine Capillary Telangiectasia

    OpenAIRE

    Gocmen, Rahsan; Kurt, Erdal; Arslan, Sabina; Unal-Cevik, Isin; Karli Oguz, Kader; Tezer, F Irsel

    2015-01-01

    This report describes a case of pontine capillary telangiectasia in a 43-year-old woman with a clinical diagnosis of trigeminal autonomic cephalgia. The possible association with pontine capillary telangiectasia and trigeminal autonomic cephalgia is discussed.

  2. Involvement of M3 Cholinergic Receptor Signal Transduction Pathway in Regulation of the Expression of Chemokine MOB-1, MCP-1 Genes in Pancreatic Acinar Cells

    Institute of Scientific and Technical Information of China (English)

    郑海; 陈道达; 张景輝; 田原

    2004-01-01

    Whether M3 cholinergic receptor signal transduction pathway is involved in regulation of the activation of NF-κB and the expression of chemokine MOB-1, MCP-1genes in pancreatic acinar cells was investigated. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, atropine and PDTC in vitro. The MOB-1 and MCP-1 mRNA expression was detected by using RT-PCR. The activation of NF-κB was monitored by using electrophoretic mobility shift assay.The results showed that as compared with control group, M3 cholinergic receptor agonist (103mol/L, 104-4ol/L carbachol) could induce a concentration-dependent and time-dependent increase in the expression of MOB-1, MCP-1 mRNA in pancreatic acinar cells. After treatment with 10 -3mol/L carbachol for 2 h, the expression of MOB-1, MCP-1 mRNA was strongest. The activity of NF-κB in pancreatic acinar cells was significantly increased (P<0.01) after treated with M3 cholinergic receptor agonist (10-3 mol/L carbachol) in vitro for 30 min. Either M3 cholinergic receptor antagonist (10-5 mol/L atropine) or NF-κB inhibitor (10-2 mol/L PDTC) could obviously inhibit the activation of NF-κB and the chemokine MOB-1, MCP-1 mRNA expression induced by carbachol (P <0.05). This inhibitory effect was significantly increased by atropine plus PDTC (P<0.01). The results of these studies indicated that M3 cholinergic receptor signal transduction pathway was likely involved in regulation of the expression of chemokine MOB-1 and MCP-1genes in pancreatic acinar cells in vitro through the activation of NF-κB.

  3. Relevance of alumina grit analysis in zircaloy fabrication process

    International Nuclear Information System (INIS)

    Zirconium based alloys are the natural choice for both fuel element and in-core structural components in the water cooled thermal reactors, namely BWRs, PWRs and PHWRs. Nuclear Fuel Complex (NFC), Hyderabad is engaged in the production of zirconium based alloys that are used as hardware in the nuclear industry. After hot working of zircaloy, due to its reactivity, an oxide layer is formed on its surfaces. Hence to remove this oxide layer grit blasting operation using alumina grit sand is followed during which the particles of the sand gets fragmented and the oxide layer on the material thus gets dislodged. Thus alumina grit plays a prominent role in the zircaloy fabrication process. In order to have an ideal and effective removal of the oxide layer from the zircaloy surface, knowledge about the composition of the grit with respect to Al2O3, SiO2, TiO2, Fe2O3, CaO and MgO is essential. Therefore the chemical compositional analysis of alumina grit for confirming to specification becomes an essential step in the Quality Assurance (QA) programme for acceptance of the material. The present paper describes the analytical methodology followed in our laboratory for the chemical analysis of alumina grit samples used in the grit blasting operations

  4. N-doped mesoporous alumina for adsorption of carbon dioxide

    Institute of Scientific and Technical Information of China (English)

    Jayshri A.Thote; Ravikrishna V.Chatti; Kartik S.Iyer; Vivek Kumar; Arti N.Valechha; Nitin K.Labhsetwar; Rajesh B.Biniwale; M.K.N.Yenkie; Sadhana S.Rayalu

    2012-01-01

    N-doped mesoporous alumina has been synthesized using chitosan as the biopolymer template.The adsorbent has been thoroughly investigated for the adsorption of CO2 from a simulated flue gas stream (15% CO2 balanced with N2) and compared with commercially available mesoporous alumina procured from SASOL,Germany.CO2 adsorption was studied under different conditions of pretreatment and adsorption temperature,inlet CO2 concentration and in the presence of oxygen and moisture.The adsorption capacity was determined to be 29.4 mg CO2/g of adsorbent at 55℃.This value was observed to be 4 times higher in comparison to that of commercial mesoporous alumina at a temperature of 55℃.Basicity of alumina surface coupled with the presence of nitrogen in template in synthesized sample is responsible for this enhanced CO2 adsorption.Adsorption capacity for CO2 was retained in the presence of oxygen; however moisture had a deteriorating effect on the adsorption capacity reducing it to nearly half the value.

  5. Alumina and Zirconia Based Layered Composites:Part 1 Preparation

    Czech Academy of Sciences Publication Activity Database

    Hadraba, Hynek; Maca, K.; Chlup, Zdeněk

    2009-01-01

    Roč. 412, - (2009), s. 221-226. ISSN 1013-9826 R&D Projects: GA ČR(CZ) GA106/06/0724 Institutional research plan: CEZ:AV0Z20410507 Keywords : electrophoretic deposition * alumina * zirconia Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

  6. High rate reactive magnetron sputtering of alumina coatings

    Czech Academy of Sciences Publication Activity Database

    Bulíř, Jiří; Novotný, Michal; Pokorný, Petr; Lančok, Ján; Musil, Jindřich

    Warrendale, PA: MRS , 2009. s. 27-28. ISBN N. [E- MRS 2009 Spring Meeting. 08.06.2009-12.06.2009, Strasbourg] Institutional research plan: CEZ:AV0Z10100522 Keywords : reactive pulsed magnetron sputtering * alumina * optical emission spectroscopy * mass spectroscopy Subject RIV: BH - Optics, Masers, Lasers

  7. Dynamical stability of the alpha and theta phases of alumina

    DEFF Research Database (Denmark)

    Lodziana, Zbigniew; Parlinski, K.

    2003-01-01

    Using density functional calculations the phonon dispersion relations, phonon density of states, and free energy of theta and alpha phases of alumina are investigated. The temperature dependence of the free energy indicates that entropy contributes to the destabilization of the alpha phase at the...

  8. Multifunctional substrates of thin porous alumina for cell biosensors

    KAUST Repository

    Toccafondi, Chiara

    2014-02-27

    We have fabricated anodic porous alumina from thin films (100/500 nm) of aluminium deposited on technological substrates of silicon/glass, and investigated the feasibility of this material as a surface for the development of analytical biosensors aiming to assess the status of living cells. To this goal, porous alumina surfaces with fixed pitch and variable pore size were analyzed for various functionalities. Gold coated (about 25 nm) alumina revealed surface enhanced Raman scattering increasing with the decrease in wall thickness, with factor up to values of approximately 104 with respect to the flat gold surface. Bare porous alumina was employed for micro-patterning and observation via fluorescence images of dye molecules, which demonstrated the surface capability for a drug-loading device. NIH-3T3 fibroblast cells were cultured in vitro and examined after 2 days since seeding, and no significant (P > 0.05) differences in their proliferation were observed on porous and non-porous materials. The effect on cell cultures of pore size in the range of 50–130 nm—with pore pitch of about 250 nm—showed no significant differences in cell viability and similar levels in all cases as on a control substrate. Future work will address combination of all above capabilities into a single device.

  9. Controlled growth of single nanowires within a supported alumina template

    Energy Technology Data Exchange (ETDEWEB)

    Vlad, A [Unite de Dispositifs Integres et Circuits Electroniques, Universite Catholique de Louvain (UCL), Place de Levant, 3, B-1348 Louvain-la-Neuve (Belgium); Matefi-Tempfli, M [Unite de Physico-Chimie et de Physique des Materiaux, UCL, Place Croix du Sud, 1, B-1348 Louvain-la-Neuve (Belgium); Faniel, S [Unite de Dispositifs Integres et Circuits Electroniques, Universite Catholique de Louvain (UCL), Place de Levant, 3, B-1348 Louvain-la-Neuve (Belgium); Bayot, V [Unite de Dispositifs Integres et Circuits Electroniques, Universite Catholique de Louvain (UCL), Place de Levant, 3, B-1348 Louvain-la-Neuve (Belgium); Melinte, S [Unite de Dispositifs Integres et Circuits Electroniques, Universite Catholique de Louvain (UCL), Place de Levant, 3, B-1348 Louvain-la-Neuve (Belgium); Piraux, L [Unite de Physico-Chimie et de Physique des Materiaux, UCL, Place Croix du Sud, 1, B-1348 Louvain-la-Neuve (Belgium); Matefi-Tempfli, S [Unite de Physico-Chimie et de Physique des Materiaux, UCL, Place Croix du Sud, 1, B-1348 Louvain-la-Neuve (Belgium)

    2006-10-14

    A simple technique for fabricating single nanowires with well-defined position is presented. The process implies the use of a silicon nitride mask for selective electrochemical growth of the nanowires in a porous alumina template. We show that this method allows the realization of complex nanowire patterns as well as arrays of single nanowires with a precise position and spacing.

  10. Controlled growth of single nanowires within a supported alumina template

    Science.gov (United States)

    Vlad, A.; Mátéfi-Tempfli, M.; Faniel, S.; Bayot, V.; Melinte, S.; Piraux, L.; Mátéfi-Tempfli, S.

    2006-10-01

    A simple technique for fabricating single nanowires with well-defined position is presented. The process implies the use of a silicon nitride mask for selective electrochemical growth of the nanowires in a porous alumina template. We show that this method allows the realization of complex nanowire patterns as well as arrays of single nanowires with a precise position and spacing.

  11. Alumina-encapsulated vaccine formulation with improved thermostability and immunogenicity.

    Science.gov (United States)

    Zhou, Hangyu; Wang, Guangchuan; Li, Xiao-Feng; Li, Yaling; Zhu, Shun-Ya; Qin, Cheng-Feng; Tang, Ruikang

    2016-05-11

    Developing vaccine formulations with excellent thermostability and immunogenicity remains a great challenge. By in situ encapsulating a live-attenuated strain of human enterovirus 71 (EV71) in alumina, we obtained a robust vaccine formulation named EV71@NanoAlum, which features significantly enhanced thermostability and immunogenicity. This attempt follows a material-based tactic for vaccine improvement. PMID:27098047

  12. Grafting of alumina on SBA-15: Effect of surface roughness

    Czech Academy of Sciences Publication Activity Database

    Zukal, Arnošt; Šiklová, Helena; Čejka, Jiří

    2008-01-01

    Roč. 24, č. 17 (2008), s. 9837-9842. ISSN 0743-7463 R&D Projects: GA AV ČR KAN100400701 Institutional research plan: CEZ:AV0Z40400503 Keywords : alumina-grafted materials * SBA-15 * Nitrogen adsorption Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.097, year: 2008

  13. Interaction of alumina with liquid Pb83Li17 alloy

    International Nuclear Information System (INIS)

    Highlights: • The role of oxygen in the interaction of alumina with Pb83Li17 alloy was studied. • Li of Pb83Li17 alloy undergoes oxidation even in flowing high pure argon atmosphere. • It was seen that alumina reacts with Pb83Li17 alloy at 550 °C to form LiAlO2 compound. • The reaction is rapid in the presence of oxygen and happens more slowly in the presence of flowing argon. - Abstract: Eutectic lead lithium (Pb83Li17) alloy is being considered a coolant, neutron multiplier and tritium breeder for International Thermonuclear Experimental Reactor (ITER) and Fusion Power Reactors (FPR). In order to reduce the magneto-hydrodynamic drag (MHD) and to prevent corrosion of structural materials due to the flow of lead lithium (Pb83Li17) alloy, alumina (Al2O3) is proposed as a candidate ceramic coating material. Interaction of liquid Pb83Li17 alloy with Al2O3 at the operating temperature of these reactors is therefore an important issue. The present paper deals with the characterization of Pb83Li17 alloy and its interaction with Al2O3 at the reactor operating temperature. The interaction was studied using EPMA, XRD and thermal analysis technique. The result indicates that alumina can interact with Pb83Li17 alloy at 550 °C even in high purity argon atmosphere. The role of oxygen in the interaction process has also been discussed

  14. Nanocomposite formed by titanium ion implantation into alumina

    International Nuclear Information System (INIS)

    Composites of titanium nanoparticles in alumina were formed by ion implantation of titanium into alumina, and the surface electrical conductivity measured in situ as the implantation proceeded, thus generating curves of sheet conductivity as a function of dose. The implanted titanium self-conglomerates into nanoparticles, and the spatial dimensions of the buried nanocomposite layer can thus be estimated from the implantation depth profile. Rutherford backscattering spectrometry was performed to measure the implantation depth profile, and was in good agreement with the calculated profile. Transmission electron microscopy of the titanium-implanted alumina was used for direct visualization of the nanoparticles formed. The measured conductivity of the buried layer is explained by percolation theory. We determine that the saturation dose, φ0, the maximum implantation dose for which the nanocomposite material still remains a composite, is φ0 = 2.2 × 1016 cm−2, and the corresponding saturation conductivity is σ0 = 480 S/m. The percolation dose φc, below which the nanocomposite still has basically the conductivity of the alumina matrix, was found to be φc = 0.84 × 1016 cm−2. The experimental results are discussed and compared with a percolation theory model

  15. Radiative properties of radially nonisothermal alumina particles with multiphase

    International Nuclear Information System (INIS)

    Accurate prediction of radiative properties of alumina (Al2O3) particle with phase transition is essential to both spray deposition of coatings and solid aluminized rocket plume diagnostics. In this paper, a theoretical model based on the electromagnetic theory is applied to determine thermal radiation of a radially inhomogeneous alumina particle having a radial temperature distribution, where a concise and efficient algorithm is developed for the calculation. The internal absorption efficiencies for single phase and multiphase particle are calculated and discussed. The absorption efficiency at the surface of multiphase alumina spherical particle is calculated by the effective-medium sphere mode, and the result is compared with that of multilayered sphere model, which shows that effective-medium sphere mode gives similar results when each layer's thickness is much less than the wavelength of the incident light. The effect of temperature difference between the center and the surface on the spectral radiant flux of multiphase alumina particle is also analyzed in this paper.

  16. State of the art: alumina ceramics for energy applications

    International Nuclear Information System (INIS)

    Prominent ceramic raw materials and products manufacturers were surveyed to determine the state of the art for alumina ceramic fabrication. This survey emphasized current capabilities and limitations for fabrication of large, high-density, high-purity, complex shapes. Some directions are suggested for future needs and development

  17. Urbach's rule criteria in alumina irradiated with ions

    International Nuclear Information System (INIS)

    Irradiation of dielectrics with ions is available for aims of the optical, mechanical and other properties modification. The defect localized states effect on alumina optical absorption properties depends on ability of incorporated elements to substitute the lattice cations. The complex energetic spectrum of the defect localized states demands the generalized approaches which characterize the radiation induced disorder in materials as a whole. The Urbach's rule criteria for the absorption spectra of alumina irradiated with the silicon, chromium and titanium ions (Φ=1017 cm-2, Ei=100 keV) were investigated. The induced defect, their clusters and hard solid solution effect on the Urbach's equation parameters was determined. Analysis the reasons of the absorption change was given. Absorption spectra of irradiated alumina were subjected the Urbach's rule as all it criteria were fulfilled. This is stipulated by the static disorder in crystalline lattice induced by substitution defects, intrinsic defects and cluster formation on its base. A common focal point in absorption spectrums situated at 4.4 eV was fixed. This Urbach's focus is determine by the processes of defects clusterization, the energetic characteristics of clusters and depend on ability of the implanted ions to form the hard solid solutions in alumina. A correlation between the interband and exponential absorption parameters indicates to synthesis in Al2O3 a new strongly defect material having band gap width near the 4.5 eV and absorption edge stipulated by the defect cluster levels. (authors)

  18. Preparation of highly-ordered carbon nanotube arrays in the anodized alumina template

    International Nuclear Information System (INIS)

    A highly-ordered, hexagonally arranged alumina nanopore template was prepared by self-organized two-step anodization process of aluminium in oxalic acid solution. Highly parallel pores were obtained within domains of a few micrometers. Highly-ordered, parallel carbon nanotube arrays were successfully grown in the alumina template nanopores by chemical vapor deposition catalyzed by alumina itself. The nanotube arrays are suitable for channeling of particle beams. The structures of aluminium, alumina template and carbon nanotubes were characterized by scanning electron microscopy (SEM) and electron back scattered diffraction (EBSD). The growth mechanism and formation condition of both alumina template and carbon nanotube were discussed. (authors)

  19. Zirconia-alumina coupling: aging of zirconia should be kept out of concern

    Energy Technology Data Exchange (ETDEWEB)

    Villermaux, F. [Norton Desmarquest Fine Ceramics, Evreux (France)

    2001-07-01

    Zirconia-alumina coupling already demonstrated its advantages as ceramic-ceramic bearing compared to alumina-alumina system: equivalent wear performance but higher mechanical reliability and increase of design possibilities (more neck lengths - head Oe22.22 mm). The last step for the in-vitro validation of this system was to investigate the wear behavior with aged zirconia head. Some hip simulator tests have been performed with artificially aged zirconia heads and showed no significant influence on the zirconia-polyethylene or zirconia-alumina wear performance. Then, zirconia-alumina can really be considered as reliable ceramic-ceramic system and aging should be kept out of concern. (orig.)

  20. Effects of maternal exposure to nano-alumina during pregnancy on neurodevelopment in offspring mice

    Institute of Scientific and Technical Information of China (English)

    丁勇

    2013-01-01

    Objective To observe the effects of maternal exposure to nano-alumina during pregnancy on the neurodevelopment in offspring mice.Methods Female ICR mice were exposed to nano-alumina 10 d before mating,and the nano-alumina exposure lasted till offspring mice were born.All the female mice were randomly divided into 5groups:solvent control group (saline) ,nano-carbon group (11.76 mg/ml) ,microalumina group (50 mg/ml) ,50 nm alumina group (50 mg/ml) ,and 13 nm alumina group (50 mg/ml) .All the mice were treated by

  1. Development of an imaging system for the detection of alumina on turbine blades

    International Nuclear Information System (INIS)

    An imaging system capable of detecting alumina on turbine blades by acquiring LED-induced fluorescence images has been developed. Acquiring fluorescence images at adjacent spectral bands allows the system to distinguish alumina from fluorescent surface contaminants. Repair and overhaul processes require that alumina is entirely removed from the blades by grit blasting and chemical stripping. The capability of the system to detect alumina has been investigated with two series of turbine blades provided by Rolls-Royce plc. The results illustrate that the system provides a superior inspection method to visual assessment when ascertaining whether alumina is present on turbine blades during repair and overhaul processes. (paper)

  2. Nuclear NF-κB p65 in peripheral blood mononuclear cells correlates with urinary MCP-1, RANTES and the severity of type 2 diabetic nephropathy.

    Directory of Open Access Journals (Sweden)

    Bin Yi

    Full Text Available AIMS: To investigate if nuclear NF-κB p65 expression in ex vivo isolated peripheral blood mononuclear cells correlates with urinary MCP-1 or RANTES and the severity of type 2 diabetic nephropathy. METHODS: According to their urinary albumin-to-creatinine ratio (uACR, 107 patients with type 2 diabetes (eGFR >60 ml/min were divided into normal albuminuria group (DN0 group, 38 cases, microalbuminuria group (DN1 group, 38 cases, and macroalbuminuria group (DN2 group, 31 cases, compared with matched healthy normal control group (NC group, 30 cases. Nuclear NF-κB p65 protein expression levels in peripheral blood mononuclear cells were detected by western blotting. Real-time quantitative polymerase chain reaction was used to detect NF-κB p65 mRNA expression and ELISA assay was used to detect the levels of urinary MCP-1 and RANTES. RESULTS: Nuclear NF-κB p65 protein and NF-κB p65 mRNA expression levels in peripheral blood mononuclear cells, urinary MCP-1/Cr and RANTES/Cr were all significantly higher in all diabetes groups as compared with NC group. In particular, the increase of nuclear NF-κB p65 protein and NF-κB p65 mRNA expressions, urinary MCP-1/Cr and RANTES/Cr all correlated with the severity of type 2 diabetic nephropathy as indicated by the increase in uACR. Pearson correlation analysis indicated that both urinary MCP-1/Cr and RANTES/Cr were positively correlated with nuclear NF-κB p65 protein or NF-κB p65 mRNA levels. Stepwise multiple regression analysis showed that nuclear NF-κB p65 protein or NF-κB p65 mRNA was an independent variable for urinary MCP-1/Cr, and MCP-1/Cr and RANTES/Cr were two independent variables for uACR. CONCLUSION: Our research demonstrates that nuclear NF-κB p65 protein and mRNA expressions in ex vivo isolated peripheral blood mononuclear cells well correlate with urinary MCP-1/Cr, RANTES/Cr and the severity of type 2 diabetic nephropathy.

  3. Qualidade de caqui 'Rama forte' após armazenamento refrigerado, influenciada pelos tratamentos 1-MCP e/ou CO2

    Directory of Open Access Journals (Sweden)

    João Peterson Pereira Gardin

    2012-12-01

    Full Text Available Avaliaram-se os efeitos dos tratamentos com CO2 e 1-MCP (1-metilciclopropeno sobre a adstringência (índice de tanino, firmeza da polpa e distúrbios da epiderme em caqui 'Rama Forte'. Frutos foram tratados com 1-MCP por 24 h, logo após a colheita e/ou com alto CO2 (70% por 24 ou 48 h, um dia após a colheita ou após o armazenamento refrigerado (AR. Os caquis foram armazenados sob atmosfera modificada a 0 ºC, por 45 dias, e a seguir mantidos a 23 ºC, por 9 dias. Frutos-controle (não tratados com 1-MCP nem com CO2 amoleceram em três dias e perderam aproximadamente 50% da adstringência em 6 dias após o AR. A exposição ao CO2 acelerou a redução da adstringência. Esse efeito do CO2 foi menor em frutos tratados com 1-MCP, especialmente quando o CO2 foi aplicado após o AR, por apenas 24 h. O tratamento com 1-MCP inibiu o amolecimento e a redução da adstringência, especialmente nos frutos não tratados com CO2. O amolecimento de frutos tratados com 1-MCP foi maior quando a exposição ao CO2 ocorreu antes do AR. A combinação dos tratamentos com 1-MCP e alto CO2 reduziu a incidência de podridões e manchas translúcidas, mas não alterou o desenvolvimento de pintas pretas ('estrias'. Os resultados indicam que é possível induzir perda da adstringência sem excessiva perda da firmeza da polpa de caquis 'Rama Forte' após o AR pela associação dos tratamentos com 1-MCP logo após a colheita e alto CO2 após o AR.

  4. Curcumin Supplementation Lowers TNF-α, IL-6, IL-8, and MCP-1 Secretion in High Glucose-Treated Cultured Monocytes and Blood Levels of TNF-α, IL-6, MCP-1, Glucose, and Glycosylated Hemoglobin in Diabetic Rats

    OpenAIRE

    Jain, Sushil K.; Rains, Justin; Croad, Jennifer; Larson, Bryon; Jones, Kimberly

    2009-01-01

    This study examined the hypothesis that curcumin supplementation decreases blood levels of IL-6, MCP-1, TNF-α, hyperglycemia, and oxidative stress by using a cell-culture model and a diabetic rat model. U937 monocytes were cultured with control (7 mM) and high glucose (35 mM) in the absence or presence of curcumin (0.01–1 μM) at 37°C for 24 h. Diabetes was induced in Sprague–Dawley rats by injection of streptozotocin (STZ) (i.p., 65 mg/kg BW). Control buffer, olive oil, or curcumin (100 mg/kg...

  5. Synthesis and structural evaluation of freeze-cast porous alumina

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Douglas F., E-mail: souzadf@outlook.com [Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais — UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG CEP: 31270-901, Escola de Engenharia, bloco 2, sala 2230 (Brazil); Nunes, Eduardo H.M., E-mail: eduardohmn@gmail.com [Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais — UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG CEP: 31270-901, Escola de Engenharia, bloco 2, sala 2230 (Brazil); Pimenta, Daiana S.; Vasconcelos, Daniela C.L. [Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais — UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG CEP: 31270-901, Escola de Engenharia, bloco 2, sala 2230 (Brazil); Nascimento, Jailton F.; Grava, Wilson [Petrobras/CENPES, Avenida Horácio Macedo 950, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ CEP:21941-915 (Brazil); Houmard, Manuel [Department of Materials Engineering and Civil Construction, Federal University of Minas Gerais — UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG CEP: 31270-901, Escola de Engenharia, bloco 1, sala 3304 (Brazil); Vasconcelos, Wander L., E-mail: wlv@demet.ufmg.br [Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais — UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG CEP: 31270-901, Escola de Engenharia, bloco 2, sala 2230 (Brazil)

    2014-10-15

    In this work we fabricated alumina samples by the freeze-casting technique using tert-butanol as the solvent. The prepared materials were examined by scanning electron microscopy and X-ray microtomography. Next, they were coated with sol–gel silica films by dip-coating. Permeability tests were carried out in order to assess the permeation behavior of the materials processed in this study. We observed that the sintering time and alumina loading showed a remarkable effect on both the structural properties and flexural strength of the freeze-cast samples. Nitrogen adsorption tests revealed that the silica prepared in this study exhibited a microporous structure. It was observed that the presence of silica coatings on the alumina surface decreased the CO{sub 2} permeance by about one order of magnitude. Because of the similar kinetic diameters of nitrogen and carbon dioxide, the CO{sub 2}/N{sub 2} system showed a separation efficiency that was lower than that observed for the He/CO{sub 2} and He/N{sub 2} systems. We noticed that increasing the feed pressure improved the separation capacity of the obtained materials. - Highlights: • Porous alumina samples obtained by the freeze-casting technique • Microporous silica coating prepared by a simple sol–gel dip-coating methodology • Samples examined by SEM, μ-CT, and nitrogen sorption tests • Mechanical tests were carried out in the freeze-cast samples. • The presence of silica coatings on the alumina surface decreased the CO{sub 2} permeance.

  6. Advanced morphological analysis of patterns of thin anodic porous alumina

    International Nuclear Information System (INIS)

    Different conditions of fabrication of thin anodic porous alumina on glass substrates have been explored, obtaining two sets of samples with varying pore density and porosity, respectively. The patterns of pores have been imaged by high resolution scanning electron microscopy and analyzed by innovative methods. The regularity ratio has been extracted from radial profiles of the fast Fourier transforms of the images. Additionally, the Minkowski measures have been calculated. It was first observed that the regularity ratio averaged across all directions is properly corrected by the coefficient previously determined in the literature. Furthermore, the angularly averaged regularity ratio for the thin porous alumina made during short single-step anodizations is lower than that of hexagonal patterns of pores as for thick porous alumina from aluminum electropolishing and two-step anodization. Therefore, the regularity ratio represents a reliable measure of pattern order. At the same time, the lower angular spread of the regularity ratio shows that disordered porous alumina is more isotropic. Within each set, when changing either pore density or porosity, both regularity and isotropy remain rather constant, showing consistent fabrication quality of the experimental patterns. Minor deviations are tentatively discussed with the aid of the Minkowski measures, and the slight decrease in both regularity and isotropy for the final data-points of the porosity set is ascribed to excess pore opening and consequent pore merging. - Highlights: • Thin porous alumina is partly self-ordered and pattern analysis is required. • Regularity ratio is often misused: we fix the averaging and consider its spread. • We also apply the mathematical tool of Minkowski measures, new in this field. • Regularity ratio shows pattern isotropy and Minkowski helps in assessment. • General agreement with perfect artificial patterns confirms the good manufacturing

  7. Advanced morphological analysis of patterns of thin anodic porous alumina

    Energy Technology Data Exchange (ETDEWEB)

    Toccafondi, C. [Istituto Italiano di Tecnologia, Department of Nanophysics, Via Morego 30, Genova I 16163 (Italy); Istituto Italiano di Tecnologia, Department of Nanostructures, Via Morego 30, Genova I 16163 (Italy); Stępniowski, W.J. [Department of Advanced Materials and Technologies, Faculty of Advanced Technologies and Chemistry, Military University of Technology, 2 Kaliskiego Str., 00-908 Warszawa (Poland); Leoncini, M. [Istituto Italiano di Tecnologia, Department of Nanostructures, Via Morego 30, Genova I 16163 (Italy); Salerno, M., E-mail: marco.salerno@iit.it [Istituto Italiano di Tecnologia, Department of Nanophysics, Via Morego 30, Genova I 16163 (Italy)

    2014-08-15

    Different conditions of fabrication of thin anodic porous alumina on glass substrates have been explored, obtaining two sets of samples with varying pore density and porosity, respectively. The patterns of pores have been imaged by high resolution scanning electron microscopy and analyzed by innovative methods. The regularity ratio has been extracted from radial profiles of the fast Fourier transforms of the images. Additionally, the Minkowski measures have been calculated. It was first observed that the regularity ratio averaged across all directions is properly corrected by the coefficient previously determined in the literature. Furthermore, the angularly averaged regularity ratio for the thin porous alumina made during short single-step anodizations is lower than that of hexagonal patterns of pores as for thick porous alumina from aluminum electropolishing and two-step anodization. Therefore, the regularity ratio represents a reliable measure of pattern order. At the same time, the lower angular spread of the regularity ratio shows that disordered porous alumina is more isotropic. Within each set, when changing either pore density or porosity, both regularity and isotropy remain rather constant, showing consistent fabrication quality of the experimental patterns. Minor deviations are tentatively discussed with the aid of the Minkowski measures, and the slight decrease in both regularity and isotropy for the final data-points of the porosity set is ascribed to excess pore opening and consequent pore merging. - Highlights: • Thin porous alumina is partly self-ordered and pattern analysis is required. • Regularity ratio is often misused: we fix the averaging and consider its spread. • We also apply the mathematical tool of Minkowski measures, new in this field. • Regularity ratio shows pattern isotropy and Minkowski helps in assessment. • General agreement with perfect artificial patterns confirms the good manufacturing.

  8. Luminescence characterisation of alumina substrates using cathodoluminescence microscopy and spectroscopy

    International Nuclear Information System (INIS)

    Polycrystalline alumina (Al2O3) substrates, found in many electronic devices and proposed as dosemeters in emergency situations, were invstigated using a scanning electron microscope (SEM) equipped with cathodoluminescence (CL) and elemental analysis probes. The characteristics of the CL spectra, surface morphology, and impurity content of the Al2O3 substrates were examined and compared with those of single crystal dosimetry-grade Al2O3:C. Whereas the CL spectrum, measured from 250 to 800 nm, for the Al2O3:C, contained resolved bands located at ∼340 nm and at ∼410 nm, the spectrum measured with the Al2O3 substrate was significantly broader, extending from ∼250 to ∼450 nm, and also included a narrow band at 695 nm. While it is likely that the accepted model of recombination at F+ (∼340 nm) and F (∼410 nm) in Al2O3:C also applies to the substrate, it is suggested that the presence of impurities within the alumina give rise to additional recombination centres. The 695 nm emission has been assigned to a Cr3+ ion impurity in previous work on alumina and a band indicated at ∼300 nm may be associated with Mg2+ or Ca2+, the presence of which was confirmed by elemental mapping. Comparison of the spatial distribution of CL with the surface morphology and elemental composition of the samples indicates that the components of the emission spectrum can be qualitatively correlated with impurity content and morphological features of the samples. - Highlights: • Morphological (SEM) and elemental characterisation (EDS/WDs) of alumina substrates. • Cathodoluminescence (CL) emission spectroscopy of alumina substrates. • Close relationship of the CL emission with the SEM and EDs/WDS characteristics

  9. Processing and Mechanical Properties of Various Zirconia/Alumina Composites for Fuel Cell Applications

    Science.gov (United States)

    Choi, Sung R.; Bansal, Narottam P.

    2002-01-01

    Various electrolyte materials for solid oxide fuel cells were fabricated by hot pressing 10 mol% yttria-stabilized zirconia (10-YSZ) reinforced with two different forms of alumina, particulates and platelets, each containing 0 to 30 mol% alumina. Flexure strength and fracture toughness of both particulate and platelet composites at ambient temperature increased with increasing alumina content, reaching a maximum at 30 mot% alumina. For a given alumina content, strength of particulate composites was greater than that of platelet composites, whereas, the difference in fracture toughness between the two composite systems was negligible. No virtual difference in elastic modulus and density was observed for a given alumina content between particulate and platelet composites. Thermal cycling up to 10 cycles between 200 to 1000 C did not show any effect on strength degradation of the 30 mol% platelet composites, indicative of negligible influence of CTE mismatches between YSZ matrix and alumina grains.

  10. High alumina metamorphic rocks of the Kings Mountain district, North Carolina and South Carolina

    Science.gov (United States)

    Potter, Donald Brandreth

    1954-01-01

    The following evidence suggests that high alumina quartzite in this district is of metasedimentary origin: high alumina quartzite occurs as well defined thin beds that can be traced up to three and one half miles along strike; many outcrops of high alumina quartzite exhibit compositional layering (i.e., kyanigte quartzite is interlayered with staurolite quartzite, and with non-kyanitic magnetiferous quartzite); high alumina quartzite beds occur in a conformable sequence of high alumina metasedimentary and metavolcanic schists. It is suggested that the high alumina quartzite beds are metamorphosed beds of sandy or silty clay; these beds probably represent one stage in the deposition of fine grained clayey clastic sediments. No evidence was found to support the view of Smith and Newcombe (1951) that the kyanite at Henry Knob developed by hudrothermal introduction of alumina. The present study indicates that kyanite in the kyanite quartzite here, as throughout the district, is of metasedimentary origin.

  11. Application of CHESS single-bounce capillaries at synchrotron beamlines

    Science.gov (United States)

    Huang, R.; Szebenyi, T.; Pfeifer, M.; Woll, A.; Smilgies, D.-M.; Finkelstein, K.; Dale, D.; Wang, Y.; Vila-Comamala, J.; Gillilan, R.; Cook, M.; Bilderback, D. H.

    2014-03-01

    Single-bounce capillaries are achromatic X-ray focusing optics that can provide efficient and high demagnification focusing with large numerical apertures. Capillary fabrication at CHESS can be customized according to specific application requirements. Exemplary applications are reviewed in this paper, as well as recent progress on condensers for high-resolution transmission X-ray microscopy and small focal size capillaries.

  12. Numerical simulations of capillary barrier field tests

    Energy Technology Data Exchange (ETDEWEB)

    Morris, C.E. [Univ. of Wollongong (Australia); Stormont, J.C. [Univ. of New Mexico, Albuquerque, NM (United States)

    1997-12-31

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior.

  13. Modeling of Throttling Process inside Capillary Tube

    Czech Academy of Sciences Publication Activity Database

    Vinš, Václav; Vacek, V.

    Praha : ČVUT, 2009, s. 250-251. ISBN 978-80-01-04286-1. [ANNUAL CTU UNIVERSITY-WIDE SEMINAR /18./. Praha (CZ), 16.02.2009-20.02.2009] Institutional research plan: CEZ:AV0Z20760514 Keywords : capillary tube * numerical model * metastable flow Subject RIV: BJ - Thermodynamics https://workshop.cvut.cz/2009/

  14. Planetary In Situ Capillary Electrophoresis System (PISCES)

    Science.gov (United States)

    Willis, P. A.; Stockton, A. M.; Mora, M. F.; Cable, M. L.; Bramall, N. E.; Jensen, E. C.; Jiao, H.; Lynch, E.; Mathies, R. A.

    2012-10-01

    We propose to develop PISCES, a 3-kg, 2W, flight-capable microfluidic lab-on-a-chip capillary electrophoresis analyzer capable of ingesting solid, liquid, or gas samples and performing a suite of chemical analyses with parts per trillion sensitivity.

  15. Imbibition of ``Open Capillary'': Fundamentals and Applications

    Science.gov (United States)

    Tani, Marie; Kawano, Ryuji; Kamiya, Koki; Okumura, Ko

    2015-11-01

    Control or transportation of small amount of liquid is one of the most important issues in various contexts including medical sciences or pharmaceutical industries to fuel delivery. We studied imbibition of ``open capillary'' both experimentally and theoretically, and found simple scaling laws for both statics and dynamics of the imbibition, similarly as that of imbibition of capillary tubes. Furthermore, we revealed the existence of ``precursor film,'' which developed ahead of the imbibing front, and the dynamics of it is described well by another scaling law for capillary rise in a corner. Then, to show capabilities of open capillaries, we demonstrated two experiments by fabricating micro mixing devices to achieve (1) simultaneous multi-color change of the Bromothymol blue (BTB) solution and (2) expression of the green florescent protein (GFP). This research was partly supported by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan). M. T. is supported by the Japan Society for the Promotion of Science Research Fellowships for Young Scientists.

  16. Analytical biotechnology: Capillary electrophoresis and chromatography

    International Nuclear Information System (INIS)

    The papers describe the separation, characterization, and equipment required for the electrophoresis or chromatography of cyclic nucleotides, pharmaceuticals, therapeutic proteins, recombinant DNA products, pheromones, peptides, and other biological materials. One paper, On-column radioisotope detection for capillary electrophoresis, has been indexed separately for inclusion on the data base

  17. Macroscopic theory for capillary-pressure hysteresis.

    Science.gov (United States)

    Athukorallage, Bhagya; Aulisa, Eugenio; Iyer, Ram; Zhang, Larry

    2015-03-01

    In this article, we present a theory of macroscopic contact angle hysteresis by considering the minimization of the Helmholtz free energy of a solid-liquid-gas system over a convex set, subject to a constant volume constraint. The liquid and solid surfaces in contact are assumed to adhere weakly to each other, causing the interfacial energy to be set-valued. A simple calculus of variations argument for the minimization of the Helmholtz energy leads to the Young-Laplace equation for the drop surface in contact with the gas and a variational inequality that yields contact angle hysteresis for advancing/receding flow. We also show that the Young-Laplace equation with a Dirichlet boundary condition together with the variational inequality yields a basic hysteresis operator that describes the relationship between capillary pressure and volume. We validate the theory using results from the experiment for a sessile macroscopic drop. Although the capillary effect is a complex phenomenon even for a droplet as various points along the contact line might be pinned, the capillary pressure and volume of the drop are scalar variables that encapsulate the global quasistatic energy information for the entire droplet. Studying the capillary pressure versus volume relationship greatly simplifies the understanding and modeling of the phenomenon just as scalar magnetic hysteresis graphs greatly aided the modeling of devices with magnetic materials. PMID:25646688

  18. Numerical simulations of capillary barrier field tests

    International Nuclear Information System (INIS)

    Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior

  19. Study on the bound water of several high specific surface-area oxides (beryllia, alumina, silica-alumina)

    International Nuclear Information System (INIS)

    This study is concerned with the bound water of several oxides (beryllia, alumina, silica-alumina) at different steps of their dehydration (heating temperatures between 150 and 1100 deg. C). The following techniques have been used simultaneously: Thermal analysis (a new method has been developed), nitrogen adsorption (study of the texture), Diborane hydrolysis (qualitative and quantitative analysis of surface water), Infra-red spectrography (in the absorption range of water), Nuclear magnetic resonance (in the resonance range of protons). Thanks to these different techniques, five kinds of bound water have been observed. Attention is called on the great influence of the thermal treatment conditions on the evolution of the products resulting from the decomposition of alumina α-trihydrate Al(OH)3 and beryllium α-hydroxide, in the course of the dehydration. Moreover, the author emphasizes the peculiar properties of the two kinds of oxides (alumina and beryllia) prepared through a new method of treatment under low pressure and constant speed of decomposition. Such particular features concern mainly texture, bound water, and consequently, also catalytic activity. (author)

  20. EFFECTIVE ELASTIC PROPERTIES OF ALUMINA-ZIRCONIA COMPOSITE CERAMICS - PART 4. TENSILE MODULUS OF POROUS ALUMINA AND ZIRCONIA

    Directory of Open Access Journals (Sweden)

    W. Pabst

    2004-12-01

    Full Text Available In this fourth paper of a series on the effective elastic properties of alumina-zirconia composite ceramics the influence of porosity on the effective tensile modulus of alumina and zirconia ceramics is discussed. The examples investigated are alumina and zirconia ceramics prepared from submicron powders by starch consolidation casting using two different types of starch, potato starch (median size D50 =47.2 µm and corn starch (median size D50 =13.7 µm. The dependence of effective tensile moduli E, on the porosity f, measured for porosities in the ranges of approx. 19-55 vol.% and 10-42 vol.% for alumina and zirconia, respectively, using a resonant frequency technique, was evaluated by fitting with various model relations, including newly developed ones. A detailed comparison of the fitting results suggests the superiority of the new relation E/E0 = (1 - f·(1 - f/fC, developed by the authors (with the tensile modulus of the dense ceramic material E0 and the critical porosity fC, over most other existing fit models. Only for special purposes and well-behaved data sets the recently proposed exponential relation E/E0 = exp [-Bf/(1 - f] and the well-known Phani-Niyogi relation E/E0 = (1 - f/fCN might be preferable.

  1. Capillary zone electrophoresis and capillary isotachophoresis applied to physicochemical characterization of oligo- and polypeptides

    Czech Academy of Sciences Publication Activity Database

    Kašička, Václav; Šolínová, Veronika; Tůmová, Tereza; Koval, Dušan; Ibrahim, A.; Chamieh, J.; Cottet, H.

    Helsinki: -, 2015. L4B. [International Symposium on Electro- and Liquid Phase-Separation Techniques (ITP2015) /22./ and Nordic Separation Science Symposium (NoSSS2015) /8./. 30.08.2015-03.09.2015, Helsinki] R&D Projects: GA ČR(CZ) GA13-17224S Institutional support: RVO:61388963 Keywords : capillary electrophoresis * capillary isotachophoresis * effective charge Subject RIV: CB - Analytical Chemistry, Separation

  2. Capillary isoelectric focusing of proteins and microorganisms in uncoated capillaries with UV and fluorimetric detection

    Czech Academy of Sciences Publication Activity Database

    Horká, Marie; Šlais, Karel; Růžička, F.; Holá, V.; Horký, J.

    Roma : Universita di Roma, 2004, P43. [ITP 2004. International Symposium on Capillary Electroseparation Techniques /14./. Roma (IT), 12.09.2004-15.09.2004] R&D Projects: GA AV ČR IAA4031302; GA AV ČR IBS4031201; GA ČR GA203/02/1447 Institutional research plan: CEZ:AV0Z4031919 Keywords : CIEF ioanalytes * uncoated capillaries Subject RIV: CB - Analytical Chemistry, Separation

  3. Development of a new fast shower maximum detector based on microchannel plates photomultipliers (MCP-PMT) as an active element

    International Nuclear Information System (INIS)

    One possibility to make a fast and radiation resistant shower maximum (SM) detector is to use a secondary emitter as an active element. We present below test beam results, obtained with different types of photodetectors based on microchannel plates (MCPs) as the secondary emitter. We performed the measurements at the Fermilab Test Beam Facility with 120 GeV proton beam and 12 GeV and 32 GeV secondary beams. The goal of the measurement with 120 GeV protons was to determine time resolution for minimum ionizing particles (MIPs). The SM time resolution we obtained for this new type of detector is at the level of 20–30 ps. We estimate that a significant contribution to the detector response originates from secondary emission of the MCP. This work can be considered as the first step in building a new type of calorimeter based on this principle

  4. Development of a new fast shower maximum detector based on microchannel plates photomultipliers (MCP-PMT) as an active element

    Science.gov (United States)

    Ronzhin, A.; Los, S.; Ramberg, E.; Spiropulu, M.; Apresyan, A.; Xie, S.; Kim, H.; Zatserklyaniy, A.

    2014-09-01

    One possibility to make a fast and radiation resistant shower maximum (SM) detector is to use a secondary emitter as an active element. We present below test beam results, obtained with different types of photodetectors based on microchannel plates (MCPs) as the secondary emitter. We performed the measurements at the Fermilab Test Beam Facility with 120 GeV proton beam and 12 GeV and 32 GeV secondary beams. The goal of the measurement with 120 GeV protons was to determine time resolution for minimum ionizing particles (MIPs). The SM time resolution we obtained for this new type of detector is at the level of 20-30 ps. We estimate that a significant contribution to the detector response originates from secondary emission of the MCP. This work can be considered as the first step in building a new type of calorimeter based on this principle.

  5. Assessment of hydrodynamic performance and structural integrity of SMART MCP impeller under a non-uniform inlet flow

    International Nuclear Information System (INIS)

    Fluid dynamic and structural analysis were performed to assess the hydrodynamic performance and the structural integrity of the SMART MCP Impeller located behind a curved suction part. FLUENT was used for the fluid dynamic analysis and I-DEAS for the structural analysis. No flow separation phenomenon was occurred but non-uniform flow approaching to the impeller was observed. The non-uniform inlet flow induced 4% lower head than the case of uniform inlet flow assumption. Because the non-uniform flow gives rise to periodic pressure oscillation on the impeller blade, stress analysis was conducted for static load and fatigue load. The structural integrity of the impeller was verified by comparing the results with the allowable stresses and the fatigue limits of the impeller material

  6. 2Kx2K resolution element photon counting MCP sensor with >200 kHz event rate capability

    International Nuclear Information System (INIS)

    Siegmund Scientific undertook a NASA Small Business Innovative Research (SBIR) contract to develop a versatile, high-performance photon (or particle) counting detector combining recent technical advances in all aspects of Microchannel Plate (MCP) detector development in a low cost, commercially viable package that can support a variety of applications. The detector concept consists of a set of MCPs whose output electron pulses are read out with a crossed delay line (XDL) anode and associated high-speed event encoding electronics. The delay line anode allows high-resolution photon event centroiding at very high event rates and can be scaled to large formats (>40 mm) while maintaining good linearity and high temporal stability. The optimal sensitivity wavelength range is determined by the choice of opaque photocathodes. Specific achievements included: spatial resolution of 200 000 events s-1; local rates of >100 events s-1 per resolution element; event timing of -2 s-1)

  7. 2Kx2K resolution element photon counting MCP sensor with >200 kHz event rate capability

    CERN Document Server

    Vallerga, J V

    2000-01-01

    Siegmund Scientific undertook a NASA Small Business Innovative Research (SBIR) contract to develop a versatile, high-performance photon (or particle) counting detector combining recent technical advances in all aspects of Microchannel Plate (MCP) detector development in a low cost, commercially viable package that can support a variety of applications. The detector concept consists of a set of MCPs whose output electron pulses are read out with a crossed delay line (XDL) anode and associated high-speed event encoding electronics. The delay line anode allows high-resolution photon event centroiding at very high event rates and can be scaled to large formats (>40 mm) while maintaining good linearity and high temporal stability. The optimal sensitivity wavelength range is determined by the choice of opaque photocathodes. Specific achievements included: spatial resolution of 200 000 events s sup - sup 1; local rates of >100 events s sup - sup 1 per resolution element; event timing of <1 ns; and low background ...

  8. O resfriamento rápido e a rápida instalação da atmosfera controlada como substitutos do 1-MCP no armazenamento de maçãs 'Gala' Fast cooling and rapid controlled atmosphere as substitute of 1-MCP on 'Gala' apple fruits storage

    Directory of Open Access Journals (Sweden)

    Auri Brackmann

    2005-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da aplicação do 1-metilciclopropeno (1-MCP associada a diferentes formas de resfriamento e de instalação da atmosfera controlada (AC sobre a qualidade da maçã 'Gala'. No primeiro experimento, os tratamentos consistiram da aplicação ou não de 1-MCP no início do armazenamento refrigerado com dois períodos necessários para o resfriamento dos frutos até a temperatura de armazenamento (0,5°C: sete dias (lento e três dias (rápido. No segundo experimento, avaliou-se o efeito da aplicação de 1-MCP associada com a instalação lenta (sete dias ou rápida (até três dias da AC (1,2kPa O2 + 2,5kPa CO2. A dose de 1-MCP utilizada foi de 660nL L-1, aplicada no início do armazenamento, durante 24 horas, a 0,5°C. No primeiro ensaio, o resfriamento dos frutos em três dias, em comparação com o resfriamento em sete dias, permitiu melhor manutenção dos atributos qualitativos dos frutos após seis meses de armazenamento refrigerado a 0,5°C e mais sete dias a 20°C, independentemente da aplicação de 1-MCP. No segundo experimento, observou-se que a instalação rápida da AC proporcionou resultados semelhantes à aplicação de 1-MCP, durante a instalação lenta, na manutenção da qualidade dos frutos, após oito meses de armazenamento em AC, a 0,5°C, e mais sete dias a 20°C. Esses resultados sugerem que o resfriamento rápido ou a rápida instalação da AC podem substituir a aplicação de 1-MCP em maçãs 'Gala'.The aim of this work was to evaluate the effect of 1-methylcyclopropene (1-MCP application associated with different rates of cooling and settlement of controlled stored atmosphere (CA on quality of 'Gala' apple fruits. In the first experiment, the treatments were with or without 1-MCP and two times to reach the storage temperature (0.5°C: 7 days (slow and 3 days (fast. The second experiment evaluated the effect of 1-MCP application and the settlement of stored CA: slow (7 days

  9. Genetic polymorphisms of RANTES, IL1-A, MCP-1 and TNF-A genes in patients with prostate cancer

    International Nuclear Information System (INIS)

    Inflammation has been implicated as an etiological factor in several human cancers, including prostate cancer. Allelic variants of the genes involved in inflammatory pathways are logical candidates as genetic determinants of prostate cancer risk. The purpose of this study was to investigate whether single nucleotide polymorphisms of genes that lead to increased levels of pro-inflammatory cytokines and chemokines are associated with an increased prostate cancer risk. A case-control study design was used to test the association between prostate cancer risk and the polymorphisms TNF-A-308 A/G (rs 1800629), RANTES-403 G/A (rs 2107538), IL1-A-889 C/T (rs 1800587) and MCP-1 2518 G/A (rs 1024611) in 296 patients diagnosed with prostate cancer and in 311 healthy controls from the same area. Diagnosis of prostate cancer was significantly associated with TNF-A GA + AA genotype (OR, 1.61; 95% CI, 1.09–2.64) and RANTES GA + AA genotype (OR, 1.44; 95% CI, 1.09–2.38). A alleles in TNF-A and RANTES influenced prostate cancer susceptibility and acted independently of each other in these subjects. No epistatic effect was found for the combination of different polymorphisms studied. Finally, no overall association was found between prostate cancer risk and IL1-A or MCP-1 polymorphisms. Our results and previously published findings on genes associated with innate immunity support the hypothesis that polymorphisms in proinflammatory genes may be important in prostate cancer development

  10. 1-methylcyclopropene (1-MCP)-induced alteration in leaf photosynthetic rate, chlorophyll fluorescence, respiration and membrane damage in rice (Oryza sativa L.) under high night temperature

    Science.gov (United States)

    High night temperature (HNT) can induce ethylene-triggered reactive oxygen species production, which can cause premature leaf senescence and membrane damage, thereby affecting production, consumption and transfer of photosynthates, and yield. The 1-methylcyclopropene (1-MCP) can competitively bind w...

  11. Concentrações de IL-6, TNF-α e MCP-1 em crianças com excesso de massa corporal

    Directory of Open Access Journals (Sweden)

    Juliano Magalhães Guedes

    2015-08-01

    Full Text Available O objetivo desta revisão sistemática foi verificar a relação das concentrações de IL-6, TNF-α e MCP-1 em crianças com excesso de massa corporal. As bases de dados investigadas PUBMED, SciELO, LILACS e Periódico Capes foram consultadas retrospectivamente para os últimos seis anos (2009 a 2014 utilizando combinações de palavras chaves como inflamação, IL-6, TNF-α, MCP-1 combinadas com crianças e escolares. Foram analisados 21 artigos. Foi encontrado associação entre sobrepeso/obesidade com IL-6, TNF-α e MCP-1 em 73,3% (11/15, 80% (12/15 e 60% (3/5 dos estudos que analisaram tais marcadores, respectivamente. Crianças com excesso de massa corporal possuem concentrações elevadas de IL-6, TNF-α e MCP-1 resultando em inflamação sistêmica crônica e aumentando o risco de desenvolvimento de outras doenças cardiovasculares. 

  12. Analysis of outcomes and prognostic factors of acute lymphoblastic leukemia patients treated by MCP841 protocol: A regional cancer center experience

    Directory of Open Access Journals (Sweden)

    Akhil Kapoor

    2016-01-01

    Full Text Available Background: A dramatic improvement in the survival of acute lymphoblastic leukemia (ALL patients in the last three decades has been observed. MCP 841 protocol is an old but effective tool with tolerable toxicities. The objective of this study was to estimate the relapse-free survival of ALL patients treated uniformly with MCP 841 protocol on the basis of various prognostic factors. Materials and Methods: The study design was retrospective and it was conducted in a regional cancer center of Northwest India. Three hundred and ten ALL patients who underwent treatment with MCP 841 protocol and regular follow-up for up to 5 years were selected for this study. Relapse-free survival was calculated by Kaplan-Meier analysis and Cox regression analysis was used to calculate the hazards ratio (HR using Statistical Package for the Social Sciences (SPSS software for windows version 20.0. Results: Fifty-four percent patients were 1 lakh/cmm had 41% survival [HR 2.14 (1.76-2.48 with, P < 0.001]. Conclusion: MCP 841 protocol is a useful tool for the treatment of ALL in children when more aggressive protocols can not be used.

  13. Capillary Interactions between a Probe Tip and a Nanoparticle

    Institute of Scientific and Technical Information of China (English)

    SUN Li-Ning; WANG Le-Feng; RONG Wei-Bin

    2008-01-01

    To understand capillary interactions between probe tips and nanoparticles under ambient conditions,a theoretical model of capillary forces between them is developed based on the geometric relations. It is found that the contribution of surface tension force to the total capillary force attains to similar order of magnitude as the capillary pressure force in many cases.It is also shown that the tip shape and the radial distance of the meniscus have great influence on the capillary force.The capillary force decreases with the increasing separation distances,and the variance of the contact angles may change the magnitudes of capillary forces several times at large radial distances.The applicability of the symmetric meniscus approximation is discussed.

  14. A study on heat transfer characteristics of spherical and fibrous alumina nanofluids

    International Nuclear Information System (INIS)

    Highlights: ► Spherical and fibrous alumina nanoparticles were prepared by pulsed wire evaporation and hydrolysis methods. ► Fibrous alumina nanofluid exhibited higher thermal conductivity enhancement than spherical one due to entangled structure of nanofibers with high aspect-ratio. ► Decreasing rate of viscosity with temperature for fibrous alumina nanofluid was much larger than that for spherical one. - Abstract: Ethylene glycol based nanofluids containing spherical/fibrous alumina nanoparticles were synthesized by pulsed wire evaporation and hydrolysis methods. The crystallographic and morphological properties of the prepared nanoparticles were analyzed by X-ray diffraction, nitrogen gas adsorption and transmission electron microscopy. The average diameter of spherical alumina nanoparticles was about 80 nm and the alumina nanofibers exhibited a high aspect ratio (length/width). The viscosity and thermal conductivity of the spherical/fibrous alumina nanofluids were experimentally measured in the temperature range from 25 to 80 °C. For the fibrous alumina nanofluid, the increase of temperature raised thermal conductivity but lowered viscosity. On the other hand, for the spherical alumina nanofluid, both thermal conductivity and viscosity were decreased with increasing temperature. In particular, the fibrous alumina nanofluid exhibited a higher enhancement of thermal conductivity than the spherical one due to the well-connected structure between entangled nanofibers with high aspect ratio.

  15. Effects of single and two stages anodizing on nonporous anodic alumina template at different potentials

    International Nuclear Information System (INIS)

    The porous anodic alumina has extensive applications as mold or template for filling the highly ordered patterned ID nanomaterials (semiconductors, magnetic nanowires etc.) and as a mask for nano dots of different materials. Pores in anodic alumina synthesized under appropriate conditions are self organized. Pore density, pore diameter, interpore distance may be changed through variation of different parameter such as anodic potential, choice of electrolyte, temperature and kind of pre-treatment. The porous anodic alumina has been synthesized by single and double stage anodizing at different potentials. The potentials used were 40V, 50V, 60V and 70V. By comparison of ordered pore formation under both the conditions, it has been found that pores formed in doubly anodized alumina are more ordered/organized than in singly anodized anodic alumina at same potential used for both type of synthesis. SEM images revealed that the pore density in the singly anodized alumina was greater than in doubly anodized alumina prepared under the same potential. Using the SEM image, the pore diameter in the case of doubly anodized alumina was found to be in the range of 50- 70 nm, whereas, for singly anodized alumina pore diameter was found to be in the range of 50-100 nm. Scanning electron Microscope images and electrochemical parameters showed that two stage anodizing is better than single stage anodizing to achieve highly ordered nanoporous alumina template. (author)

  16. Capillary Penetration into Inclined Circular Glass Tubes.

    Science.gov (United States)

    Trabi, Christophe L; Ouali, F Fouzia; McHale, Glen; Javed, Haadi; Morris, Robert H; Newton, Michael I

    2016-02-01

    The spontaneous penetration of a wetting liquid into a vertical tube against the force of gravity and the imbibition of the same liquid into a horizontal tube (or channel) are both driven by capillary forces and described by the same fundamental equations. However, there have been few experimental studies of the transition from one orientation to the other. We report systematic measurements of capillary penetration of polydimethylsiloxane oils of viscosities 9.6, 19.2, and 48.0 mPa·s into glass capillary tubes. We first report the effect of tube radii R between 140 and 675 μm on the dynamics of spontaneous imbibition. We show that the data can be fitted using the exact numerical solution to the governing equations and that these are similar to fits using the analytical viscogravitational approximation. However, larger diameter tubes show a rate of penetration slower than expected using an equilibrium contact angle and the known value of liquid viscosity. To account for the slowness, an increase in viscosity by a factor (η/ρ)scaling is needed. We show full agreement with theory requires the ratio R/κ(-1) ∼ 0.1 or less, where κ(-1) is the capillary length. In addition, we propose an experimental method that enables the determination of the dynamic contact angle during imbibition, which gives values that agree with the literature values. We then report measurements of dynamic penetration into the tubes of R = 190 and 650 μm for a range of inclination angles to the horizontal, φ, from 5 to 90°. We show that capillary penetration can still be fitted using the viscogravitational solution, rather than the Bosanquet solution which describes imbibition without gravity, even for inclination angles as low as 10°. Moreover, at these low angles, the effect of the tube radius is found to diminish and this appears to relate to an effective capillary length, κ(-1)(φ) = (γLV/ρg sin φ)(1/2). PMID:26738739

  17. A novel covalent coating of capillaries for capillary electrophoresis coupled to matrix assisted laser desorption ionization

    International Nuclear Information System (INIS)

    Capillary electrophoresis (CE) offers the advantage of flexibility and method development. It excels in the area of separation of ions, chiral, polar, and biological compounds (especially proteins and peptides). Masking the active sites on the inner surface of a bare fused-silica capillary wall is often necessary for CE separations of basic compounds, proteins and peptides. The use of capillary surface coatings is an approach to prevent adsorption phenomena and improve the repeatability of these analytes. In this work, new capillary coatings consisting of (I) derivatized polystyrene nanoparticles (PS) and (II) derivatized fullerenes, were investigated for the analysis of peptides and protein digest by CE. The coated capillaries showed excellent run-to-run and batch-to-batch reproducibility (RSD of migration time ≤ 0.5 % for run to run and ≤ 9.5 % for batch-to-batch experiments). Furthermore, the capillaries offer high stability from pH 2.0 up to pH 10.0. The actual potential of the coated capillaries was tested by combining CE with matrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS) for analysing complex samples, such as peptides, whereas the overall performance of the CE-MALDI-TOF-MS system was investigated by analysing a five protein digest mixture. Subsequently, the peak list (peptide mass fingerprint) generated from the mass spectra of each fraction was entered into the Swiss Prot database in order to search for matching tryptic fragments using the Mascot software. The sequence coverage of analysed proteins was between 36-68%. The established technology benefits from the synergism of high separation efficiency and the structure selective identification via MS. (author)

  18. Study of preparation and surface morphology of self-ordered nanoporous alumina; Estudo da preparacao e da morfologia de superficie de alumina nanoporosa auto-organizada

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Elisa Marchezini; Martins, Maximiliano Delany, E-mail: elisamarch@gmail.com, E-mail: MG.mdm@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG. (Brazil); Silva, Ronald Arreguy, E-mail: arregsilva@yahoo.com.br [Centro Universitario de Belo Horizonte (UniBH), Belo Horizonte, MG (Brazil)

    2013-07-01

    Nanoporous alumina is a typical material that exhibits self-ordered nanochannels spontaneously organized in hexagonal shape. Produced by anodizing of metallic aluminum, it has been used as a template for production of materials at the nanoscale. This work aimed to study the preparation of nanoporous alumina by anodic anodizing of metallic aluminum substrates. The nanoporous alumina was prepared following the methodology proposed by Masuda and Fukuda (1995), a two-step method consisting of anodizing the aluminum sample in the potentiostatic mode, removing the layer of aluminum oxide (alumina) formed and then repeat the anodization process under the same conditions as the first anodization. This method produces nanoporous alumina with narrow pore diameter distribution and well-ordered structure. (author)

  19. Nano α-alumina powders from aluminium dross waste

    International Nuclear Information System (INIS)

    The paper describes a solvo thermal chemical process to recycle aluminium dross waste into nano α-alumina powder. The process includes washing to remove the unwanted sodium follow by dissolving of this waste with dilute acid. The solvo thermal process then proceed with addition of propanol to crystallize the aluminium hydroxide. XRD analysis of this crystal shows that it belongs to Gibbs site (Al(OH)3). The crystals were then calcined at 1300 degree C where white powder was produced. Characteristic studies were then performed on this powder using XRD, SEM, EDX and particle size analysis showing that it has single α-alumina crystal phase with almost spherical shape. As the initial particle size is coarse and had a mean particle size of 3.80 μm, high speed wet milling was used and enable to reduce it to 0.49 μm. (Author)

  20. Synthesis of Porous Nano Alumina Powder by Combustion Method

    International Nuclear Information System (INIS)

    Development of Porous Alumina powder by combustion technique using glysine fuel and aluminum nitrate as and oxidizer is able to produce porous Alpha alumina powders. Thermodynamic modeling of the combustion reaction show that as the fuel to oxidant ratio increases, the amount of gases produced and adiabatic flame temperature also increase. X-ray diffraction showed the amorphous structure for as-synthesized powder and present of well-crystallized a- Al2O3 after calcination at 1100 degree Celsius. Morphology microstructure of pore size ranging between 134-495 nm were observed by SEM. The crystallite size (Scherrer) is observed at ∼568.2 A and FWHM 0.143 degree. (author)

  1. Catalyst materials based on plasma-processed alumina nanopowder

    Directory of Open Access Journals (Sweden)

    Dubencovs Konstantins

    2012-01-01

    Full Text Available A platinum catalyst for glycerol oxidation by molecular oxygen has been developed applying the extractive-pyrolytic method and using, as a support, a fine alumina powder with an average particle size of 30-60 nm processed by plasma technology. The extractive-pyrolytic method (EPM allows affixing small amounts of catalytic metals (1-5% with the particle size ranging from several nanometers to several tens of nanometers onto the surface of the support. The prepared material - 4.8 wt. % platinum on nano-sized alumina - can be used as a catalyst for glycerol oxidation by oxygen with conversion up to 84%, in order to produce some organic acids (glyceric and lactic acid with a selectivity of about 60%.

  2. Epitaxial growth of tungsten nanoparticles on alumina and spinel surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Suarez, T; Lopez-Esteban, S; Pecharroman, C; Esteban-Cubillo, A; Moya, J S [Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Cientificas (CSIC), C/ Sor Juana Ines de la Cruz 3, 28049, Cantoblanco, Madrid (Spain); Diaz, L A; Torrecillas, R [Nanomaterials and Nanotechnology Research Center (CINN), Consejo Superior de Investigaciones CientIficas (CSIC), C/ Francisco Pintado Fe 26, 33011, Oviedo, Asturias (Spain); Gremillard, L [Universite de Lyon, INSA-Lyon, MATEIS, UMR CNRS 5510, 20 avenue Albert Einstein, Villeurbanne F-69621 (France)], E-mail: jsmoya@icmm.csic.es

    2008-05-28

    Isolated tungsten nanoparticles ({alpha}-W and {beta}-W phase) were synthesized and epitaxially grown on alumina and spinel particle surfaces with an average tungsten size of {<=}20 nm for a low tungsten content (of {<=}1.5 vol%). Using tungsten (VI) ethoxide alcoholic solutions, tungsten trioxide hydrated precursors were attached to a ceramic grains surface as a nanoparticle coating. High-resolution transmission electron microscopy (HRTEM) micrographs showed epitaxial interfaces between alumina, spinel and metallic tungsten. This epitaxial growth is assumed to be due to the effect of water vapour on the sublimation of ortho-tungstic acid during the reduction process in a hydrogen atmosphere. The planes involved in the epitaxy were found to be (22-bar 0){sub Al2O3} parallel (121){sub W} and (311){sub MgAl2O4} parallel (110){sub W}.

  3. Effect of alumina on silicon carbide bodies with clay bonding

    International Nuclear Information System (INIS)

    Components made of silicon carbide are very important ceramic products due to their good resistance against thermal shocks. Home made of such products having silicate bonding usually have various defects in their structures. In this research effects of alumina addition on the components made of silicon carbide with clay bonding have been investigated, in order to see its effects on mechanical and structural properties such as blistering. Addition of up to 15 weights %. Al2O3 improved thermal shock resistance and increased bending strength from 25 MPa to 32 MPa due to Al2O3 transformation to mullite. However, when the amounts of alumina exceed 15 weights % mechanical strength as well as resistance to thermal shock reduced due to reman ing of Al2O3 in the components after sintering

  4. Preparation of zirconia-alumina powder by co-precipitation

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A zirconia-alumina powder with a near spherical shape and an average size of 0.1 ~ 0.2μm was prepared byco-precipitation. XRD analysis shows that α-Al2O3 phase may be directly transformed from amorphous in calcining the hydroxide composite. The ZrO2-Al2O3 composite ceramics manufactured from this powder has the maximum fracture toughness of 9 M Pa·m- 1/2 at 15 % ZrO2 and 740 MPa fracture strength at 5 % ZrO2. Zirconia grains about 1 μm in diameter aredispersed uniformly in the alumina ceramic matrix

  5. Positron energy-loss measurements in thin alumina films

    International Nuclear Information System (INIS)

    Transmitted-positron energy loss measurements were performed on approximately 100A alumina films with incident positron energies ranging from 0.5 to 3.0 keV. The positrons were electrostatically focussed on the film and the transmitted positrons were energy analyzed using a four-grid retarding field analyzer coupled with a two-stage channel electron multiplier plate connected with a phosphor screen. A strong transmitted elastic peak as well as indications of discrete energy losses were detected in these measurements. The observed discrete loss effects occurred at an average energy of approx. 25 eV and possibly approx. 50 eV. These findings are consistent with reported electron loss peaks due to plasmon excitation in alumina films

  6. Melt processing of Bi--2212 superconductors using alumina

    Science.gov (United States)

    Holesinger, Terry G.

    1999-01-01

    Superconducting articles and a method of forming them, where the superconducting phase of an article is Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.y (Bi-2212). Alumina is combined with Bi-2212 powder or Bi-2212 precursor powder and, in order to form an intimate mixture, the mixture is melted and rapidly cooled to form a glassy solid. The glassy solid is comminuted and the resulting powder is combined with a carrier. An alternative to melting is to form the mixture of nanophase alumina and material having a particle size of less than about 10 microns. The powder, with the carrier, is melt processed to form a superconducting article.

  7. Process for High-Rate Fabrication of Alumina Nanotemplates

    Science.gov (United States)

    Myung, Nosang; Fleurial, Jean-Pierre; Yun, Minhee; West, William; Choi, Daniel

    2007-01-01

    An anodizing process, at an early stage of development at the time of reporting the information for this article, has shown promise as a means of fabricating alumina nanotemplates integrated with silicon wafers. Alumina nanotemplates are basically layers of alumina, typically several microns thick, in which are formed approximately regular hexagonal arrays of holes having typical diameters of the order of 10 to 100 nm. Interest in alumina nanotemplates has grown in recent years because they have been found to be useful as templates in the fabrication of nanoscale magnetic, electronic, optoelectronic, and other devices. The present anodizing process is attractive for the fabrication of alumina nanotemplates integrated with silicon wafers in two respects: (1) the process involves self-ordering of the holes; that is, the holes as formed by the process are spontaneously arranged in approximately regular hexagonal arrays; and (2) the rates of growth (that is, elongation) of the holes are high enough to make the process compatible with other processes used in the mass production of integrated circuits. In preparation for fabrication of alumina nanotemplates in this process, one first uses electron-beam evaporation to deposit thin films of titanium, followed by thin films of aluminum, on silicon wafers. Then the alumina nanotemplates are formed by anodizing the aluminum layers, as described below. In experiments in which the process was partially developed, the titanium films were 200 A thick and the aluminum films were 5 m thick. The aluminum films were oxidized to alumina, and the arrays of holes were formed by anodizing the aluminum in aqueous solutions of sulfuric and/or oxalic acid at room temperature (see figure). The diameters, spacings, and rates of growth of the holes were found to depend, variously, on the composition of the anodizing solution, the applied current, or the applied potential, as follows: In galvanostatically controlled anodizing, regardless of the

  8. Electrochemically grown metallic nanocomb structures on nanoporous alumina templates

    International Nuclear Information System (INIS)

    Electrochemical growth of metallic nanocomb structures on anodized alumina templates is described. Nanocombs originate from the orderly growth and merger of very thin (d=15±5 nm) metallic nanowires which do not completely fill much larger pores (d∼100 nm) in the alumina template (t≤3 μm). Instead, the nanowires prefer growing along the inner corners of the hexagonal pores, coalescing into a highly ordered structure as they emerge, resulting a metallic form reminiscent of the topology of the original template. We disclose here the typical processing conditions and the microstructure of this previously unknown material as observed with a scanning electron microscope (SEM) and energy dispersive x-ray (EDX) spectroscopy. It is shown that Au nanocombs have an anomalous EDX spectra and can emit electrons at a field of ∼1 kV/cm.

  9. Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons (Cucumis melo var. makuwa Makino)

    Institute of Scientific and Technical Information of China (English)

    BAI Xiao-hang; TENG Lu-hua; LÜ De-qing; QI Hong-yan

    2014-01-01

    Compared to other melon types, oriental sweet melon (Cucumis melo var. makuwa Makino) is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co-treatment of enhanced freshness formulation (EFF) and 1-methylcyclopropene (1-MCP) on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars (Yumeiren and Tianbao) during storage. The melons were stored in incubators with temperature of 15°C and a relative humidity of 85%for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit ifrmness, water content and soluble solids content. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities showed lfuctuations in treated melons, while lipoxygenase (LOX) activity (P<0.01) and malondialdehyde (MDA) content (P<0.05) decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneifcial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.

  10. Interfacial characterization of alumina-to-alumina joints fabricated using silver–copper–titanium interlayers

    International Nuclear Information System (INIS)

    Two Ag–Cu–Ti interlayers with different compositions (Ag–35.3Cu–1.75Ti and Ag–26.7Cu–4.5Ti) were used to join sintered polycrystalline Al2O3 having different amounts of porosity to investigate the effect of titanium and porosity contents on evolution of interfacial chemistry and microstructures. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive spectroscopy (EDS) were used to characterize the interfacial microstructure. Two reaction layers, Ti2O and Cu3Ti3O, were found at the interface of Ag–Cu–Ti interlayers and Al2O3 using a series of simulated and experimental selected area diffraction patterns (SADP) of TEM and EDS. The total thickness of Ti2O and Cu3Ti3O reaction layers at the interfaces increases with increasing amounts of Ti in the Ag–Cu–Ti interlayers but is independent of the porosity content in the Al2O3. Two possible formation mechanisms of Ti2O and Cu3Ti3O reaction layers at the interface of Ag–Cu–Ti interlayers and Al2O3 have been proposed based on the interfacial characterization performed in the present study. - Highlights: • Effect of alumina porosity and % Ti in interlayer on interface structure delineated • SEM, EDS, XRD, TEM with SADP used to delineate phases, compositions, crystallography • Ti2O and Cu3Ti3O reaction layers identified and their formation mechanisms proposed

  11. a Comprehensive Model for Capillary Pressure Difference across a Drop/bubble Flowing Through a Constricted Capillary

    Science.gov (United States)

    Liang, Mingchao; Wei, Junhong; Han, Hongmei; Fu, Chengguo; Liu, Jianjun

    2015-09-01

    The capillary pressure is one of the crucial parameters in many science and engineering applications such as composite materials, interface science, chemical engineering, oil exploration, etc. The drop/bubble formation and its mechanisms that affect the permeability of porous media have steadily attracted much attention in the past. When a drop/bubble moves from a larger capillary to a smaller one, it is often obstructed by an additional pressure difference caused by the capillary force. In this paper, a comprehensive model is derived for the capillary pressure difference when a drop/bubble flows through a constricted capillary, i.e. a geometrically constricted passage with an abrupt change in radius. The proposed model is expressed as a function of the smaller capillary radius, pore-throat ratio, contact angle, surface tension and length of the drop/bubble in the smaller capillary. The model predictions are compared with the available experimental data, and good agreement is found between them.

  12. Proton adsorption onto alumina: extension of multisite complexation (MUSIC) theory

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, K.; Blum, F.D.

    1999-09-01

    The adsorption isotherm of protons onto a commercial {gamma}-alumina sample was determined in aqueous nitric acid with sodium nitrate as a background electrolyte. Three discrete regions could be discerned in the log-log plots of the proton isotherm determined at the solution pH 5 to 2. The multisite complexation (MUSIC) model was modified to analyze the simultaneous adsorption of protons onto various kinds of surface species.

  13. Impact loading of an aluminum/alumina composite

    OpenAIRE

    Johnson, J.; Hixson, R.; Gray, G

    1994-01-01

    The combined demands of increased strength and reduced weight in modern dynamic structural applications require improved understanding of composite materials subject to impact conditions. In order to isolate and identify individual contributions to composite material behavior under these conditions, an experimental and theoretical program was undertaken to examine dynamic behavior of an aluminum/alumina composite consisting of a 6061-T6 aluminum matrix containing elastic, spherical Al2O3 incl...

  14. INVESTIGATION OF THERMAL SHOCK BEHAVIOUR IN ALUMINA BASED REFRACTORY BRICKS

    OpenAIRE

    N. Sinan KÖKSAL; B. Sadık ÜNLÜ; Cevdet MERİÇ

    2003-01-01

    cUnderstanding of mechanical and thermal properties of refractory bricks used in industry is an important aspect to determine appropriate operating conditions. In this study, commercial refractory materials used in the sector of iron steel 45 % and 80 % alumina (Al2O3) of content refractory bricks were investigated. To determinate thermal shock behavior and mechanical properties of samples, thermal shock tests were applied by quenching in the water at the temperature differences of 500, 70...

  15. Results of recent KROTOS FCI tests. Alumina vs. corium melts

    Energy Technology Data Exchange (ETDEWEB)

    Huhtiniemi, I.; Magallon, D.; Hohmann, H. [Commission of the European Communities, Ispra (Italy). Joint Research Center

    1998-01-01

    Recent results from KROTOS fuel-coolant interaction experiments are discussed. Five tests with alumina were performed under highly subcooled conditions, all of these tests resulted in spontaneous steam explosions. Additionally, four tests were performed at low subcooling to confirm, on one hand, the suppression of spontaneous steam explosions under such conditions and, on the other hand, that such a system is still triggerable using an external initiator. The other test parameters in these alumina tests included the melt superheat and the initial pressure. All the tests in the investigated superheat range (150 K - 750 K) produced a steam explosion and no evidence of the explosion suppression by the elevated initial pressure (in the limited range of 0.1 - 0.375 MPa) was observed in the alumina tests. The corium test series include a test with 3 kg of melt under both subcooled and near saturated conditions at ambient pressure. Two additional tests were performed with subcooled water; one test was performed at an elevated pressure of 0.2 MPa with 2.4 kg of melt and another test with 5.1 kg of melt at ambient pressure. None of these tests with corium produced a propagating energetic steam explosion. However, propagating low energy (about twice the energy of the trigger pulse) events were observed. All corium tests produced significantly higher water level swells during the mixing phase than the corresponding alumina tests. Present experimental evidence suggests that the water depletion in the mixing zone suppresses energetic steam explosions with corium melts at ambient pressure and in the present pour geometry. Processes that could produce such a difference in void generation are discussed. (author)

  16. Deposition of Layered Double Hydroxides on Alumina Support

    Czech Academy of Sciences Publication Activity Database

    Kovanda, F.; Jirátová, Květa; Koloušek, D.

    Szeged : University of Szeged, 2010 - (Zaharia, L.), s. 748 ISSN 0324-6523. [Mid-European Clay Conference (MECC 2010) /5./. Budapest (HU), 25.08.2010-29.08.2010] R&D Projects: GA ČR GAP106/10/1762; GA ČR GA106/09/1664 Institutional research plan: CEZ:AV0Z40720504 Keywords : alumina support * hydroxydes * ldh Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  17. Porous Alumina and Zirconia Ceramics With Tailored Thermal Conductivity

    Czech Academy of Sciences Publication Activity Database

    Gregorová, E.; Pabst, W.; Sofer, Z.; Jankovský, O.; Matějíček, Jiří

    2012-01-01

    Roč. 395, č. 1 (2012), 012022-012022. ISSN 1742-6588. [European Thermal Sciences Conference (Eurotherm)/6./. Poitiers, 04.09.2012-07.09.2012] Institutional support: RVO:61389021 Keywords : Ceramics * alumina * zirconia * porosity * thermal conductivity * pore-forming agent * oxide ceramics * starch * porosity Subject RIV: JK - Corrosion ; Surface Treatment of Materials http://iopscience.iop.org/1742-6596/395/1/012022/pdf/1742-6596_395_1_012022.pdf

  18. Ordered Nanomaterials Thin Films via Supported Anodized Alumina Templates

    OpenAIRE

    Mohammed eES-SOUNI; Salah ehabouti

    2014-01-01

    Supported anodized alumina template films with highly ordered porosity are best suited for fabricating large area ordered nanostructures with tunable dimensions and aspect ratios. In this paper we first discuss important issues for the generation of such templates, including required properties of the Al/Ti/Au/Ti thin film heterostructure on a substrate for high quality templates. We then show examples of anisotropic nanostructure films consisting of noble metals using these templates, discus...

  19. Ordered Nanomaterial Thin Films via Supported Anodized Alumina Templates

    OpenAIRE

    Es-Souni, Mohammed; Habouti, Salah

    2014-01-01

    Supported anodized alumina template films with highly ordered porosity are best suited for fabricating large-area ordered nanostructures with tunable dimensions and aspect ratios. In this paper, we first discuss important issues for the generation of such templates, including required properties of the Al/Ti/Au/Ti thin-film heterostructure on a substrate for high-quality templates. We then show examples of anisotropic nanostructure films consisting of noble metals using these templates, discu...

  20. Fischer-Tropsch synthesis on alumina supported cobalt catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Bechara, R.; Balloy, D.; Vanhove, D.

    1997-11-01

    Physico-chemical properties of Co/Al{sub 2}O{sub 3}-gamma were investigated by XRD, XPS, thermogravimetry and catalytic measurements. Interactions between the metal and its support were found for catalysts prepared from alumina with the greater specific area. For the Fischer-Tropsch synthesis, the products distribution appeared not to be sensitive to the cobalt particle size, but seems to depend on the degree of cobalt reduction.