WorldWideScience

Sample records for pt processes involving

  1. Investigation of Deep Inelastic Scattering Processes Involving Large p$_{T}$ Direct Photons in the Final State

    CERN Multimedia

    2002-01-01

    This experiment will investigate various aspects of photon-parton scattering and will be performed in the H2 beam of the SPS North Area with high intensity hadron beams up to 350 GeV/c. \\item a) The directly produced photon yield in deep inelastic hadron-hadron collisions. Large p^T direct photons from hadronic interactions are presumably a result of a simple annihilation process of quarks and antiquarks or of a QCD-Compton process. The relative contribution of the two processes can be studied by using various incident beam projectiles @p|+, @p|-, p and in the future @*. \\item b) The correlations between directly produced photons and their accompanying hadronic jets. We will examine events with a large p^T direct photon for away-side jets. If jets are recognised their properties will be investigated. Differences between a gluon and a quark jet may become observable by comparing reactions where valence quark annihilations (away-side jet originates from a gluon) dominate over the Q (away-side jet originates fro...

  2. Tuning coercive force by adjusting electric potential in solution processed Co/Pt(111) and the mechanism involved

    Science.gov (United States)

    Chang, Cheng-Hsun-Tony; Kuo, Wei-Hsu; Chang, Yu-Chieh; Tsay, Jyh-Shen; Yau, Shueh-Lin

    2017-03-01

    A combination of a solution process and the control of the electric potential for magnetism represents a new approach to operating spintronic devices with a highly controlled efficiency and lower power consumption with reduced production cost. As a paradigmatic example, we investigated Co/Pt(111) in the Bloch-wall regime. The depression in coercive force was detected by applying a negative electric potential in an electrolytic solution. The reversible control of coercive force by varying the electric potential within few hundred millivolts is demonstrated. By changing the electric potential in ferromagnetic layers with smaller thicknesses, the efficiency for controlling the tunable coercive force becomes higher. Assuming that the pinning domains are independent of the applied electric potential, an electric potential tuning-magnetic anisotropy energy model was derived and provided insights into our knowledge of the relation between the electric potential tuning coercive force and the thickness of the ferromagnetic layer. Based on the fact that the coercive force can be tuned by changing the electric potential using a solution process, we developed a novel concept of electric-potential-tuned magnetic recording, resulting in a stable recording media with a high degree of writing ability.

  3. Studies of surface processes of electrocatalytic reduction of CO2 on Pt(210), Pt(310) and Pt(510)

    Institute of Scientific and Technical Information of China (English)

    FAN; ChunJie; FAN; YouJun; ZHEN; ChunHua; ZHENG; QingWei; SUN; ShiGang

    2007-01-01

    Surface processes of CO2 reduction on Pt(210), Pt(310), and Pt(510) electrodes were studied by cyclic voltammetry. Different surface structures of these platinum single crystal electrodes were obtained by various treatment conditions. The experimental results illustrated that the electrocatalytic activity of Pt single crystal electrodes towards CO2 reduction is decreased in an order of Pt(210)>Pt(310)>Pt(510), i.e., with the decrease of (110) step density on well-defined surfaces. When the surfaces were reconstructed due to oxygen adsorption, the catalytic activity of all the three electrodes has been enhanced to a certain extent. Although the activity order remains unchanged, the electrocatalytic activity has been enhanced more significantly as the density of (110) step sites is more intensive on the Pt single crystal surface. It has revealed that the more open the surface structure is, the more active the Pt single crystal electrode will be, and the easier for the electrode to be transformed into a surface structure that exhibits higher activity under external inductions. However, the relatively ordered surfaces of Pt single crystal electrode are comparatively stable under the same external inductions. The present study has gained knowledge on the interaction between CO2 and Pt single crystal electrode surfaces at a microscopic level, and thrown new insight into understanding the surface processes of electrocatalytic reduction of CO2.

  4. Atomic Aggregation Processes in the Early Stages of Pt/Pt(111) Growth

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Guo-Ce; ZHU Xiao-Bin; WANG Wei

    2000-01-01

    The atomic aggregation processes in the early stages of Pt/Pt(111) growth are studied by using kinetic Monte Carlo simulations. Our results show that the average neighbor coordination number of the atoms in a cluster is a function of temperature, agreeing well with the experiment observations of scanning tunneling microscopy. The influence of diffusion barriers of various atomic processes on the morphology of islands is also studied. Different morphologies of the islands (dendritic, fractal, or compact islands) are found.

  5. Colloidal processing of PMN-PT thick films for piezoelectric sensor applications

    Science.gov (United States)

    Luo, Hongyu

    65%Pb(Mg1/3Nb2/3)O3-35%PbTiO3 (65PMN-35PT, or PMN-PT) is a highly piezoelectric ceramic with superior piezoelectric coefficients over the more popular Pb(Zr0.5Ti0.5)O 3 (PZT). Because of its complex chemistry and high volatility of lead above 1000°C, the perovskite phase of PMN-PT is hard to process and has prevented PMN-PT from various piezoelectric applications, especially in the new area of piezoelectric micro-electro-mechanical systems (PMEMS) involving thick or thin piezoelectric films. In this thesis, a novel precursor suspension method is introduced that substantially lowers the sintering temperature of PMN-PT to 850°C from a PMN precursor powder made by coating Mg(OH) 2 on Nb2O5 particles. The precursor suspension method entails suspending PMN powders in PT precursor and uses the reaction sintering capability of PMN with nano-sized PT in the temperature range of 800°C˜1000°C. Moreover, free-standing PMN-PT thick films were obtained by tape casting the PMN-PT powder. This new geometry of PMN-PT shows giant electric-field enhanced piezoelectric responses comparable with those of single crystals. As an example of application, the PMN-PT thick film is bonded to a thinner layer of copper by electroplating and made into piezoelectric cantilever sensors. In conclusion, the colloidal suspension processing method produces free-standing PMN-PT thick films with ultrahigh piezoelectric properties.

  6. Analysis of Business Process at PT XYZ by Using SCOR Thread Diagram

    Science.gov (United States)

    Sembiring, M. T.; Rambe, H. C.

    2017-03-01

    Supply Chain Operations Reference (SCOR) is a standard supply chain performance evaluation model which is proposed by Supply Chain Council (SCC). SCOR makes companies can analyse and evaluate their supply chain performance. SCOR has Thread Diagram which describes business process simply and systematically to help the analysis of company’s business process. This research takes place in PT XYZ that is involved in Crude Palm Oil (CPO) industry. PT XYZ used to be the market leader of CPO industry but nowadays they have a trouble to compete with new competitors. The purpose of this study is to provide the input for PT XYZ business process improvement to enhance the competitiveness of the company with the others. The result obtained shows that there are two performance metrics that are not reached. The analysis of business process shows the lack of control role of PT XYZ to supplier and customer side which is going to be the suggestion of improvement.

  7. Investigation of Pt-Ti doped carbon aerogel as bi-metallic catalyst for H/D exchange process

    Science.gov (United States)

    Bhartiya, Sushmita; Kohli, D. K.; Singh, Ashish; Singh, Rashmi; Singh, M. K.

    2017-05-01

    Platinum (Pt) carbon based catalyst for hydrogen-deuterium (H/D) exchange between hydrogen and water is one of the benign processes being explored for heavy water production. Platinum being precious, presents a significant contribution on overall cost of catalyst. Titanium (Ti), a potential catalyst was explored for the H/D exchange to reduce the cost of catalyst. Titanium oxide co-doped with platinum in carbon aerogel (CA) was investigated for the exchange process. The present studies involve synthesis and characterization of TiO2 nanoparticles doped in carbon aerogel. Pt and TiO2 doping (5% by weight for both) in CA was used to prepare the bimetallic PtTi-CA catalyst. The H/D exchange efficiency obtained for the PtTi-CA catalyst (with 50% Pt economy) was 57% which compares well with Pt-CA catalyst having exchange efficiency of 67%.

  8. Industrial processes of olefin metathesis. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Warwel, S.

    1987-05-01

    Olefin metathesis opens new synthetic routes to typical petrochemicals (ethylene, propylene, n-butenes), special olefins (neohexene, higher molecular linear olefins, , -dienes) and unsaturated polymers (polynorbornene, -cyclooctene, -dicyclopentadiene) in an industrial scale. The 8 metathesis processes used in industry and further possible applications of olefin metathesis are reviewed.

  9. Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation; Preparacao e caracterizacao de eletrocatalisadores PtRu, PtSn, PtRh, PtRuRh e PtSnRh para oxidacao direta de alcoois em celulas a combustivel tipo PEM utilizando a metodologia da reducao por alcool

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Ricardo Rodrigues

    2009-07-01

    In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), SnCl{sub 2}.2H{sub 2}O (Aldrich),and RhCl{sub 2}.XH{sub 2}O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2{theta} =40 deg, 47 deg, 67 deg and 82 deg, which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2-3 nm. For Pt Sn/C and PtSnRh/C two additional peaks were observed at 2 = 34 deg and 52 deg that were identified as a SnO{sub 2} phase. Pt Sn/C (50:50) and PtSnRh/C (50:40:10) electro catalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature Pt Ru/C, Pt Sn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

  10. Measurement of the (gamma,n) reaction rates of the nuclides 190Pt, 192Pt, and 198Pt in the astrophysical gamma-process

    CERN Document Server

    Vogt, K; Babilon, M; Enders, J; Hartmann, T; Hutter, C; Rauscher, T; Volz, S; Zilges, A

    2001-01-01

    The nucleosynthesis of heavy neutron-deficient nuclei in a stellar photon bath at the temperatures relevant for the astrophysical gamma process was investigated. In order to derive (gamma,n) cross sections and reaction rates, the stellar photon bath was simulated by the superposition of several bremsstrahlung spectra with different endpoint energies. As a first test for this method, the (gamma,n) reaction rates of the platinum isotopes 190Pt, 192Pt, and 198Pt were derived. The results are compared to other experimental data and theoretical calculations.

  11. Sol-Gel Process for Making Pt-Ru Fuel-Cell Catalysts

    Science.gov (United States)

    Narayanan, Sekharipuram; Valdez, Thomas; Kumta, Prashant; Kim, Y.

    2005-01-01

    A sol-gel process has been developed as a superior alternative to a prior process for making platinum-ruthenium alloy catalysts for electro-oxidation of methanol in fuel cells. The starting materials in the prior process are chloride salts of platinum and ruthenium. The process involves multiple steps, is time-consuming, and yields a Pt-Ru product that has relatively low specific surface area and contains some chloride residue. Low specific surface area translates to incomplete utilization of the catalytic activity that might otherwise be available, while chloride residue further reduces catalytic activity ("poisons" the catalyst). In contrast, the sol-gel process involves fewer steps and less time, does not leave chloride residue, and yields a product of greater specific area and, hence, greater catalytic activity. In this sol-gel process (see figure), the starting materials are platinum(II) acetylacetonate [Pt(C5H7O2)2, also denoted Pt-acac] and ruthenium(III) acetylacetonate [Ru(C5H7O2)3, also denoted Ru-acac]. First, Pt-acac and Ru-acac are dissolved in acetone at the desired concentrations (typically, 0.00338 moles of each salt per 100 mL of acetone) at a temperature of 50 C. A solution of 25 percent tetramethylammonium hydroxide [(CH3)4NOH, also denoted TMAH] in methanol is added to the Pt-acac/Ruacac/ acetone solution to act as a high-molecular-weight hydrolyzing agent. The addition of the TMAH counteracts the undesired tendency of Pt-acac and Ru-acac to precipitate as separate phases during the subsequent evaporation of the solvent, thereby helping to yield a desired homogeneous amorphous gel. The solution is stirred for 10 minutes, then the solvent is evaporated until the solution becomes viscous, eventually transforming into a gel. The viscous gel is dried in air at a temperature of 170 C for about 10 hours. The dried gel is crushed to make a powder that is the immediate precursor of the final catalytic product. The precursor powder is converted to the

  12. DHA involvement in neurotransmission process

    Directory of Open Access Journals (Sweden)

    Vancassel Sylvie

    2007-05-01

    Full Text Available The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6 and docosahexaenoic acids (DHA, 22: 6n-3, is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6 and_-linolenic acids (18: 3n-3. Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved remain unknown. Several years ago, we hypothesized that a modification of DHA contents of neuronal membranes by dietary modulation could change the neurotransmission function and then underlie inappropriate behavioural response. We showed that, in parallel to a severe loss of brain DHA concomitant to a compensatory substitution by 22:5n-6, the dietary lack of α-linolenic acid during development induced important changes in the release of neurotransmitters (dopamine, serotonin, acetylcholine in cerebral areas specifically involved in learning, memory and reward processes. Data suggested alteration of presynaptic storage process and dysregulations of reciprocal functional interactions between monoaminergic and cholinergic pathways. Moreover, we showed that recovery of these neurochemical changes was possible when the deficient diet was switched to a diet balanced in n-3 and n-6 PUFA before weaning. The next step is to understand the mechanism involved. Particularly, we focus on the study of the metabolic cooperation between the endothelial cell, the astrocyte and the neuron which regulate synaptic transmission.These works could contribute to the understanding of the link between some neuropsychiatric disorders and the metabolism of n-3 PUFA, through their action on neurotransmission.

  13. The origin of polarity dependent switching type in solution processed Pt/TiO2/Pt memory devices

    Science.gov (United States)

    Biju, K. P.

    2015-06-01

    Resistive switching characteristics of sol-gel processed TiO2 thin films are investigated. The influence of polarity of the forming voltage on switching type in Pt/TiO2/Pt stack is investigated. Reliability and stability of the device is significantly improved by choosing a proper voltage polarity on electroforming. The device shows excellent switching properties such as high on/off ratio (> 20), good cycling endurance and long retention (> 104 s) and possible to use multi bit storage has been demonstrated. The switching mechanism is explained by a physical model based on localized generation/recovery of oxygen vacancy defects.

  14. Dehydrocoupling reactions of dimethylamine-borane by Pt(II) complexes: a new mechanism involving deprotonation of boronium cations.

    Science.gov (United States)

    Roselló-Merino, Marta; López-Serrano, Joaquín; Conejero, Salvador

    2013-07-31

    Coordinatively unsaturated Pt(II) complex [Pt(I(t)Bu')(I(t)Bu)](+) stabilized by N-heterocyclic carbene (NHC) ligands dehydrogenates N,N-dimethylamineborane through a mechanism that involves hydride abstraction, assisted by an amine, to yield a platinum-hydride complex [PtH(I(t)Bu')(I(t)Bu)] with concomitant formation of the boronium cation [(NHMe2)2BH2](+). This latter species is very likely in equilibrium with the THF stabilized borenium cation [(NHMe2)(THF)BH2](+), bearing an acidic NH group that is able to protonate the platinum hydride [PtH(I(t)Bu')(I(t)Bu)] releasing H2, the amino borane H2B-NMe2 and regenerating the catalytic [Pt](+) species.

  15. Molecular Dynamics Simulation Study of Atomic Segregation of (PdPt)147 during the Heating Process

    Science.gov (United States)

    Xiao, X. Y.; Cheng, Z. F.; Xia, J. H.

    Research on the influence of alloy concentration and distribution on bimetallic cluster plays a key role in exploring new structural material. This paper studies the melting process of icosahedral bimetallic cluster (PdPt)147 with different Pt concentrations and different atomic distributions by using molecular dynamics with an embedded atom method. The results indicate that the mixed Pd-Pt cluster shows an irregular phenomenon between 580 and 630 K, i.e. the atomic energy decreases with the increase of temperature. This is because the surface energy of Pd is lower than that of Pt; the decreased energy due to Pd atomic segregation is larger than the increased energy due to heating during the segregation process. In addition, the temperature of Pd atomic segregation is strongly related to Pt concentration. This leads to that Pd atoms prefer to remain on the surface even after the cluster melted.

  16. Enhancing Photocatalytic Performance through Tuning the Interfacial Process between -Assembled and Pt-Loaded Microspheres

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2012-01-01

    Full Text Available This work reports on a simple two-step approach to rutile TiO2-assembled microspheres loaded by Pt with an aim to tune semiconductor-metal interfacial processes for enhancing the photocatalytic performance. Systematic sample characterizations and structural analysis indicate that Pt loading did not produce any significant influences on the lattice structure of TiO2-assembled microspheres. Instead, upon Pt loading, Schottky barrier was formed in the interfaces between microspheres and Pt nanoparticles, which inhabited efficiently the recombination of photo-generated electron-hole pairs essential for the photocatalytic activities. In addition, TiO2 microspheres also showed a capacity of electrons storage and releasing as represented by a high dielectric constant, which increased the utility rate of photogenerated electrons. All these structural advantages contribute to the excellent photocatalytic activity under ultraviolet light irradiation. The interfacial process between microspheres and Pt nanoparticles was further tuned through adjusting the loading Pt content of metal Pt. As a consequence, the best photocatalytic activity on TiO2 was obtained at 0.85 wt% Pt loading, above or below which photocatalytic activity was apparently decreased.

  17. PtProcess: An R Package for Modelling Marked Point Processes Indexed by Time

    Directory of Open Access Journals (Sweden)

    David Harte

    2010-10-01

    Full Text Available This paper describes the package PtProcess which uses the R statistical language. The package provides a unified approach to fitting and simulating a wide variety of temporal point process or temporal marked point process models. The models are specified by an intensity function which is conditional on the history of the process. The user needs to provide routines for calculating the conditional intensity function. Then the package enables one to carry out maximum likelihood fitting, goodness of fit testing, simulation and comparison of models. The package includes the routines for the conditional intensity functions for a variety of standard point process models. The package is intended to simplify the fitting of point process models indexed by time in much the same way as generalized linear model programs have simplified the fitting of various linear models. The primary examples used in this paper are earthquake sequences but the package is intended to have a much wider applicability.

  18. Relationship between the catalytic activity of Pt/alumina and the relaxation process of the photoexcited electrons

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Junji, E-mail: j-itou@mail.nissan.co.jp [Advanced Materials Laboratory, Nissan Research Center, NISSAN MOTOR CO., LTD., 1 Natsushima-cho, Yokosuka-shi, Kanagawa 237-8523 (Japan); Department of Applied Physics and Chemistry, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 (Japan); Hanaki, Yasunari [Advanced Materials Laboratory, Nissan Research Center, NISSAN MOTOR CO., LTD., 1 Natsushima-cho, Yokosuka-shi, Kanagawa 237-8523 (Japan); Shen, Qing [Department of Applied Physics and Chemistry, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 (Japan); Department of Engineering Science, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 (Japan); PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Toyoda, Taro [Department of Applied Physics and Chemistry, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 (Japan); Department of Engineering Science, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585 (Japan)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer We determined the decay time of photoexcited electrons of Pt/Al{sub 2}O{sub 3}. Black-Right-Pointing-Pointer Faster decay of excited electrons in Pt/Al{sub 2}O{sub 3} leads to its faster oxidation rate. Black-Right-Pointing-Pointer Decreasing excited electron lifetime in Pt/Al{sub 2}O{sub 3} may decrease Pt consumption in catalytic convertors. - Abstract: In order to decrease the consumption of precious metals used in the catalytic converters used in automobiles, we studied the relationship between the catalytic activity of Pt/alumina (Pt/Al{sub 2}O{sub 3}) and the relaxation process of photoexcited electrons. Firstly, we studied the relationship between the size of the Pt particles in Pt/Al{sub 2}O{sub 3} and catalytic performance. Secondly, the relationship between the size of the Pt particles in Pt/Al{sub 2}O{sub 3} and the decay time of the excited electrons was studied using an improved transient grating (TG) technique. The results showed that faster decay of the excited electrons leads to greater oxidation rates. The decay time obtained with the improved TG technique gives an indication of the time that the exited electrons take to return to the ground state. According to studies utilizing FT-IR, one of the processes necessary for quickly generating CO{sub 2} with Pt is that the electron in the Pt-O bond moves to the Pt side and that the Pt{sup +} becomes Pt metal. Thus, the decay time obtained with the improved TG technique corresponds to the process whereby Pt{sup +} returns to Pt metal. Thus, we found that the consumption of precious metals can be reduced by increasing the speed of the decay of the excited electrons.

  19. The synthesis of Pt/Ag bimetallic nanoparticles using a successive solution plasma process.

    Science.gov (United States)

    Kim, Sung Min; Lee, Sang Yul; Lee, Min Hyung; Kim, Jung Wan

    2014-12-01

    A successive solution plasma process was developed for the synthesis of Pt/Ag bimetallic nanoparticles. Ag nanoparticles were made first by applying a high voltage of bipolar pulsed DC to anode and cathode electrodes composed of Ag rods. The solution containing Ag nanoparticles was discharged successively using Pt electrodes. The joule heating and electrolysis between electrodes generated vapors, and solution plasma was sustained due to progressive ionization and excitation in the vapor phase. The maximum current and voltage breakdown was observed at approximately 8.9 A and 900 V with an interval of 25 μs, which indicated that an intense solution plasma was sustained continuously. The Pt-on-Ag heterogeneous nanostructures formed, and finally, the Ag nanoparticles were completely covered by Pt nanoparticles after a discharge duration of 1,200 s.

  20. The magnetic properties and microstructure of Co-Pt thin films using wet etching process.

    Science.gov (United States)

    Lee, Chang-Hyoung; Cho, Young-Lae; Lee, Won-Pyo; Suh, Su-Jeong

    2014-11-01

    Perpendicular magnetic recording (PMR) is a promising candidate for high density magnetic recording and has already been applied to hard disk drive (HDD) systems. However, media noise still limits the recording density. To reduce the media noise and achieve a high signal-to-noise ratio (SNR) in hard disk media, the grains of the magnetic layer must be magnetically isolated from each other. This study examined whether sputter-deposited Co-Pt thin films can have adjacent grains that are physically isolated. To accomplish this, the effects of the sputtering conditions and wet etching process on magnetic properties and the microstructure of the films were investigated. The film structure was Co-Pt (30 nm)/Ru (30 nm)/NiFe (10 nm)/Ta (5 nm). The composition of the Co-Pt thin films was Co-30.7 at.% Pt. The Co-Pt thin films were deposited in Ar gas at 5, 10, 12.5, and 15 mTorr. Wet etching process was performed using 7% nitric acid solution at room temperature. These films had high out-of-plane coercivity of up to 7032 Oe, which is twice that of the as-deposited film. These results suggest that wet etched Co-Pt thin films have weaker exchange coupling and enhanced out-of-plane coercivity, which would reduce the medium noise.

  1. Synthesis and characteristics of Ag/Pt bimetallic nanocomposites by arc-discharge solution plasma processing.

    Science.gov (United States)

    Pootawang, Panuphong; Saito, Nagahiro; Takai, Osamu; Lee, Sang-Yul

    2012-10-05

    Arc discharge in solution, generated by applying a high voltage of unipolar pulsed dc to electrodes of Ag and Pt, was used as a method to form Ag/Pt bimetallic nanocomposites via electrode erosion by the effects of the electric arc at the cathode (Ag rod) and the sputtering at the anode (Pt rod). Ag/Pt bimetallic nanocomposites were formed as colloidal particles dispersed in solution via the reduction of hydrogen radicals generated during discharge without the addition of chemical precursor or reducing agent. At a discharge time of 30 s, the fine bimetallic nanoparticles with a mean particle size of approximately 5 nm were observed by transmission electron microscopy (TEM). With increasing discharge time, the bimetallic nanoparticle size tended to increase by forming an agglomeration. The presence of the relatively small amount of Pt dispersed in the Ag matrix could be observed by the analytical mapping mode of energy-dispersive x-ray spectroscopy and high-resolution TEM. This demonstrated that the synthesized particle was in the form of a nanocomposite. No contamination of other chemical substances was detected by x-ray photoelectron spectroscopy. Hence, solution plasma could be a clean and simple process to effectively synthesize Ag/Pt bimetallic nanocomposites and it is expected to be widely applicable in the preparation of several types of nanoparticle.

  2. Effect of substrates on phase formation in PMN-PT 68/32 thin films by sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P. [Department of Physics, National Institute of Technology, Rourkela 769008 (India)], E-mail: pvn77@rediffmail.com; Sonia; Patel, R.K. [Department of Chemistry, National Institute of Technology, Rourkela 769008 (India); Prakash, C. [DRDO Bhawan, Rajaji Marg, New Delhi 110011 (India); Goel, T.C. [BITS Pilani-Goa Campus, Goa 403720 (India)

    2008-07-15

    PMN-PT 68/32 thin films have been prepared on Pt/Si, ITO coated glass, stainless steel and silicon substrates in the identical processing conditions by sol-gel process. Annealing temperature of 600 deg. C was ascertained by thermo gravimetric analysis (TGA) study of the dried sol-gel powder of PMNT-PT 68/32 composition. X-ray diffraction (XRD) study showed {approx}95% perovskite phase formation on Pt/Si and ITO coated glass substrates. SEM micrographs showed the formation of sub micron size grains on Pt/Si and ITO coated glass substrates. Diffuse phase transition with transition temperature (T{sub c}) {approx}190 deg. C was observed in 0.8 {mu}m thick PMN-PT 68/32 films deposited on Pt/Si and ITO coated glass substrates.

  3. Green supply chain management strategy selection using analytic network process: case study at PT XYZ

    Science.gov (United States)

    Adelina, W.; Kusumastuti, R. D.

    2017-01-01

    This study is about business strategy selection for green supply chain management (GSCM) for PT XYZ by using Analytic Network Process (ANP). GSCM is initiated as a response to reduce environmental impacts from industrial activities. The purposes of this study are identifying criteria and sub criteria in selecting GSCM Strategy, and analysing a suitable GSCM strategy for PT XYZ. This study proposes ANP network with 6 criteria and 29 sub criteria, which are obtained from the literature and experts’ judgements. One of the six criteria contains GSCM strategy options, namely risk-based strategy, efficiency-based strategy, innovation-based strategy, and closed loop strategy. ANP solves complex GSCM strategy-selection by using a more structured process and considering green perspectives from experts. The result indicates that innovation-based strategy is the most suitable green supply chain management strategy for PT XYZ.

  4. Spin versus helicity in processes involving transversity

    CERN Document Server

    Mekhfi, Mustapha

    2011-01-01

    We construct the spin formalism in order to deal in a direct and natural way with processes involving transversity which are now of increasing popularity. The helicity formalism which is more appropriate for collision processes of definite helicity has been so far used also to manage processes with transversity, but at the price of computing numerous helicity amplitudes generally involving unnecessary kinematical variables.In a second step we work out the correspondence between both formalisms and retrieve in another way all results of the helicity formalism but in simpler forms.We then compute certain processes for comparison.A special process:the quark dipole magnetic moment is shown to be exclusively treated within the spin formalism as it is directly related to the transverse spin of the quark inside the baryon.

  5. Magnetization Reversal Processes in Pt/Co Multilayers Studied by a Magnetic Force Microscope

    Institute of Scientific and Technical Information of China (English)

    张臻蓉; 韩宝善; 刘洪

    2001-01-01

    We have studied the magnetic reversal process of magnetron sputtered Pt/Co multilayers by using a magneticforce microscope with in situ bias magnetic fields. In thin films, magnetic reversal is usually dominated either bydomain nucleation or by domain wall motion. In our experiments, a series of magnetic images in situ capturedin the same area indicates that the magnetic reversal in Pt/Co multilayers is dominated by domain nucleation,instead of domain wall motion. In addition, the. local demagnetized curve was obtained by using the bearinganalysis of the domains in the series of magnetic images.

  6. Glial cells are involved in itch processing

    DEFF Research Database (Denmark)

    Andersen, Hjalte H.; Arendt-Nielsen, Lars; Gazerani, Parisa

    2016-01-01

    Recent discoveries in itch neurophysiology include itch-selective neuronal pathways, the clinically relevant non-histaminergic pathway, and elucidation of the notable similarities and differences between itch and pain. Potential involvement of glial cells in itch processing and the possibility...

  7. PtLGBP, a pattern recognition receptor in Portunus trituberculatus involved in the immune response against different challenges.

    Science.gov (United States)

    Chen, Y-E; Jin, S; Zhao, Q-S; Zhang, Y; Wang, C-L

    2014-09-01

    Lipopolysaccharide and b-1,3-glucan binding protein (LGBP) is a pattern recognition receptor that can recognize and bind LPS and b-1,3-glucan. LGBP has crucial roles in innate immune defense against Gram-negative bacteria and fungi. In this study, LGBP functions in Portunus trituberculatus innate immunity were analyzed. First, the mRNA expression of PtLGBP in hemocytes, hepatopancreas, and muscle toward three typical pathogen-associated molecular patterns (PAMPs) stimulations were examined using real-time PCR. Results show that the overall trend of relative expressions of the LGBP gene in three tissues is consistent, showing up-down trend. In each group, the highest expression of the LGBP gene was at 3 and 12 h post-injection. The LGBP gene is also expressed significantly higher in the hemocytes and hepatopancreas than in the muscle. The highest level of LGBP was in the lipopolysaccharides (LPS) and glucan-injected group, whereas the lowest level was in the PGN-injected group. Furthermore, bacterial agglutination assay with polyclonal antibody specifically for PtLGBP proved that the recombinant PtLGBP (designated as rPtLGBP) could exhibit obvious agglutination activity toward Gram-negative bacteria Escherichia coli, Vibrio parahaemolyticus, and V. alginolyticus; Gram-positive bacteria Bacillus subtilis; and fungi Saccharomyces cerevisiae. LGBP in Portunus trituberculatus possibly served as a multi-functional PRR. In addition, LGBP is not only involved in the immune response against Gram-negative and fungi, as manifested in other invertebrates, but also has a significant role in anti-Gram-positive bacteria infection.

  8. Structural control of ultra-fine CoPt nanodot arrays via electrodeposition process

    Science.gov (United States)

    Wodarz, Siggi; Hasegawa, Takashi; Ishio, Shunji; Homma, Takayuki

    2017-05-01

    CoPt nanodot arrays were fabricated by combining electrodeposition and electron beam lithography (EBL) for the use of bit-patterned media (BPM). To achieve precise control of deposition uniformity and coercivity of the CoPt nanodot arrays, their crystal structure and magnetic properties were controlled by controlling the diffusion state of metal ions from the initial deposition stage with the application of bath agitation. Following bath agitation, the composition gradient of the CoPt alloy with thickness was mitigated to have a near-ideal alloy composition of Co:Pt =80:20, which induces epitaxial-like growth from Ru substrate, thus resulting in the improvement of the crystal orientation of the hcp (002) structure from its initial deposition stages. Furthermore, the cross-sectional transmission electron microscope (TEM) analysis of the nanodots deposited with bath agitation showed CoPt growth along its c-axis oriented in the perpendicular direction, having uniform lattice fringes on the hcp (002) plane from the Ru underlayer interface, which is a significant factor to induce perpendicular magnetic anisotropy. Magnetic characterization of the CoPt nanodot arrays showed increase in the perpendicular coercivity and squareness of the hysteresis loops from 2.0 kOe and 0.64 (without agitation) to 4.0 kOe and 0.87 with bath agitation. Based on the detailed characterization of nanodot arrays, the precise crystal structure control of the nanodot arrays with ultra-high recording density by electrochemical process was successfully demonstrated.

  9. Tunable magnetism on the lateral mesoscale by post-processing of Co/Pt heterostructures

    Directory of Open Access Journals (Sweden)

    Oleksandr V. Dobrovolskiy

    2015-04-01

    Full Text Available Controlling magnetic properties on the nanometer-scale is essential for basic research in micro-magnetism and spin-dependent transport, as well as for various applications such as magnetic recording, imaging and sensing. This has been accomplished to a very high degree by means of layered heterostructures in the vertical dimension. Here we present a complementary approach that allows for a controlled tuning of the magnetic properties of Co/Pt heterostructures on the lateral mesoscale. By means of in situ post-processing of Pt- and Co-based nano-stripes prepared by focused electron beam induced deposition (FEBID we are able to locally tune their coercive field and remanent magnetization. Whereas single Co-FEBID nano-stripes show no hysteresis, we find hard-magnetic behavior for post-processed Co/Pt nano-stripes with coercive fields up to 850 Oe. We attribute the observed effects to the locally controlled formation of the CoPt L10 phase, whose presence has been revealed by transmission electron microscopy.

  10. Innovative Pedagogical Processes Involving Educational Technology

    DEFF Research Database (Denmark)

    Weitze, Charlotte Lærke

    it experimented with gamified learning designs. This involved the students designing digital games while implementing learning goals from their curriculum. The project thus created knowledge about which learning designs and competence development models were possible in this environment, which learning designs...... about how design and learning processes can support continuous pedagogical innovation and competence development. The objective of the learning designs was to create motivating learning experiences for the students in the hybrid synchronous video-mediated learning environment, to which end...

  11. APLIKASI ANALYTIC NETWORK PROCESS (ANP PADA PERANCANGAN SISTEM PENGUKURAN KINERJA (Studi Kasus pada PT. X

    Directory of Open Access Journals (Sweden)

    Iwan Vanany

    2003-01-01

    Full Text Available The paper discusses the application of Analytic Network Process (ANP to support the weighted of design performance measurement system with Balanced Scorecard method. During the time, the weighted uses method that disregarding interdependence between objectives strategy and Key Performance Indicator (KPI's. The method which often used in this weighted is Analytical Hierarchy Process (AHP. In fact this condition does not express the concept of strategy map of Balanced Scorecard. Therefore is needed apply the other weighted method which attention to the interdependence between Key Performance Indicator (KPI. Application of the weighted with ANP method is conducted at one of the power company. This company represents result of restructuring of PT. PLN (Persero. The result of design performance measurement system of PT. X are objective strategy, Key Performance Indicator (KPI and strategy map, will be weighted by method of ANP. Further more Modeling of ANP based on strategy map. The result of application indicates that related of model of strategy map in Balanced Scorecard at PT. X is Feedback Network (hiernet with phenomenon of inner and dependence of outer dependence. The perspective on Balanced Scorecard is identically with cluster on ANP, while objective strategy and KPI are identically with sub-element and element. Result of weighted with ANP method shows the existence of culmination of weighted on financial perspective of Strategy Map at PT. X. Abstract in Bahasa Indonesia : Makalah ini membahas aplikasi Analytic Network Process (ANP untuk mendukung pembobotan pada perancangan sistem pengukuran kinerja dengan metode Balanced Scorecard. Selama ini, pembobotan yang ada menggunakan metode yang mengabaikan saling keterkaitan antar strategi objektif dengan Key Performance Indicator (KPI-KPI -nya. Metode yang sering digunakan didalam pembobotan ini adalah Analytical Hierarchy Process (AHP. Kondisi ini sebenarnya tidak mencerminkan konsep Strategy Map

  12. Innovative Pedagogical Processes Involving Educational Technology

    DEFF Research Database (Denmark)

    Weitze, Charlotte Lærke

    it experimented with gamified learning designs. This involved the students designing digital games while implementing learning goals from their curriculum. The project thus created knowledge about which learning designs and competence development models were possible in this environment, which learning designs......This design-based research project investigates the elements, methods, processes and practices that can contribute to the creation of reflected, innovative and motivating learning designs for teachers and students in a hybrid synchronous video-mediated teaching context, with a focus on how...... to create motivating learning for the students. This was done by examining the three actors in the educational institution (students, teachers and the surrounding organisation) individually and relationally. The design-based research project developed knowledge in co-design processes with the three actors...

  13. Preparation of PtSnCu/C and PtSn/C electrocatalysts and activation by dealloying processes for ethanol electrooxidation; Preparacao de eletrocatalisadores PtSnCu/C e PtSn/C e ativacao por processos de dealloying para aplicacao na oxidacao eletroquuimica do etanol

    Energy Technology Data Exchange (ETDEWEB)

    Crisafulli, Rudy

    2013-06-01

    PtSnCu/C (with different Pt:Sn:Cu atomic ratios) and PtSn/C (50:50) electrocatalysts were prepared by borohydride (BR) and alcohol-reduction (AR) processes using H{sub 2}PtCl{sub 6}.6H{sub 2}O, SnCl{sub 2}.2H{sub 2}O and CuCl{sub 2}.2H{sub 2}O as metal sources, NaBH{sub 4} and ethylene glycol as reducing agents, 2-propanol and ethylene glycol/water as solvents and carbon black as support. In a further step, these electrocatalysts were activated by chemical (CD) and electrochemical (ED) dealloying processes through acid treatment and thin porous coating technique, respectively. These materials were characterized by energy dispersive X-ray, Xray diffraction, transmission electron microscopy, line scan energy dispersive Xray and cyclic voltammetry. Electrochemical studies for ethanol electro-oxidation were performed by cyclic voltammetry, chronoamperometry and in single Direct Ethanol Fuel Cell using Membrane Electrode Assembly (MEA). The anodic effluents were analysed by gas chromatography. The X-ray diffractograms of the as-synthesized electrocatalysts showed the typical face-centered cubic structure (FCC) of platinum and its alloys. After dealloying, the X-ray diffractograms showed that the Pt FCC structure was preserved. The crystallite sizes of the assynthesized electrocatalysts were in the range of <=2 nm to 3 nm and after dealloying there were no significant variations in sizes. The energy dispersive Xray analysis of the as-synthesized electrocatalysts showed a Pt:Sn and Pt:Sn:Cu atomic ratios similar to the nominal values. After chemical and electrochemical dealloying of the electrocatalysts the ranged Pt:Sn and Pt:Sn:Cu atomic ratios showed that Cu and Sn atoms were removed. However, chemical dealloying process proved to be more efficient for removing Cu and electrochemical dealloying for removing Sn. The line scan energy dispersive X-ray analysis showed that acid and electrochemical treatments were efficient to dealloying Cu and/or Sn superficial atoms of

  14. Involvement of youth in Impact Assessment processes

    DEFF Research Database (Denmark)

    Skjervedal, Anna-Sofie Hurup; Hansen, Anne Merrild

    2017-01-01

    Initial studies of the current public participation (PP) forms, public consultations and workshops, applied in Greenland in relation to Impact Assessments (IAs) of oil-gas and mineral projects, have revealed a narrow representation of the local communities. The local representatives involved...... in the PP processes comprise primarily elder men, whereas the youth remain absent. The fast growing development in the natural resource area has already sparked societal change among the widespread communities in Greenland; changes that set high demands for a greater higher educated workforce among...... complementary alternative methods to the current PP forms. Through combining social media and the visual anthropological method of photo-interviewing, this paper seeks to give voice to the absent voice of the young Greenlanders, encouraging them to engage and have their say in these important matters regarding...

  15. Towards an integration of affiliated companies energy audit process system at P.T Astra International

    Science.gov (United States)

    Telaga, Abdi Suryadinata; Hartanto, Indra Dwi; Audina, Debby Rizky; Prabowo, Fransiscus Dimas

    2017-06-01

    Environmental awareness, stringent regulation and soaring energy costs, together make energy efficiency as an important pillar for every company. Particularly, in 2020, the ministry of energy and mineral resources of Indonesia has set a target to reduce carbon emission by 26%. For that reason, companies in Indonesia have to comply with the emission target. However, there is trade-off between company's productivity and carbon emission. Therefore, the companies' productivity must be weighed against the environmental effect such as carbon emission. Nowadays, distinguish excessive energy in a company is still challenging. The company rarely has skilled person that capable to audit energy consumed in the company. Auditing energy consumption in a company is a lengthy and time consuming process. As PT Astra International (AI) have 220 affiliated companies (AFFCOs). Occasionally, direct visit to audit energy consumption in AFFCOs is inevitable. However, capability to conduct on-site energy audit was limited by the availability of PT AI energy auditors. For that reason, PT AI has developed a set of audit energy tools or Astra green energy (AGEn) tools to aid the AFFCOs auditor to be able to audit energy in their own company. Fishbone chart was developed as an analysis tool to gather root cause of audit energy problem. Following the analysis results, PT AI made an improvement by developing an AGEn web-based system. The system has capability to help AFFCOs to conduct energy audit on-site. The system was developed using prototyping methodology, object-oriented system analysis and design (OOSAD), and three-tier architecture. The implementation of system used ASP.NET, Microsoft SQL Server 2012 database, and web server IIS 8.

  16. Robust Pt1000 temperature sensor for cryogenic applications in the process measurement technology; Robuste Pt1000-Temperaturfuehler fuer kryogene Anwendungen in der Prozessmesstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Ramalingam, Rajini Kumar; Langhans, Oliver; Suesser, Manfred [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Technische Physik (ITEP)

    2012-07-01

    The process measurement technology has a great demand for robust temperature sensors for temperatures between 20 and 500 K. The field of application is for example the hydrogen technology or the utilization of neon for the cooling of high temperature superconductors. Pt1000 temperature sensors with a shell conductor are investigated for this large range of temperatures in the calibration laboratory of the Institute for Technical Physics (Eggenstein-Leopoldshafen, Federal Republic of Germany). The Pt1000 temperature sensors were supplied by the manufacturer. The specific characteristic lines of 21 temperature sensors were determined. Furthermore, the thermal stability was investigated by means of multiple temperature cycles between 78 and 525 K. The contribution under consideration presents the investigations of this institute in detail and discusses the measurement results with regard to the industrial process measurement technology.

  17. Amphibole equilibria as monitors of P-T path and process in the exhumation of HP/UHP terranes

    Science.gov (United States)

    Waters, David; Airaghi, Laura; Czertowicz, Thomas

    2014-05-01

    Recent advances in modelling and the development of refined activity-composition relations allow the calculation of phase diagrams involving complex mineral solid solutions, such as calcic, sodic-calcic and sodic amphiboles (e.g. Diener et al., 2007, J metamorphic Geol.). Amphiboles are commonly found in eclogite facies metabasites, and formed at different metamorphic stages. Such rocks commonly show complex reaction microstructures that reveal their history. The focus in this contribution is on two distinct amphibole types: coarse, post-peak matrix amphibole, and amphibole involved in symplectitic microstructures replacing omphacite. These studies serve as a test of the current activity models and calculation approaches, but more importantly as a framework for understanding the processes and P-T path during exhumation of subducted terranes. Examples are taken from the Western Gneiss Complex of Norway and from the Kaghan Valley (Pakistan), but are more generally applicable to crustal blocks that have exhumed through the P-T 'window' in which comparable petrological features develop. The microstructural types of interest here are: broad irregular interstitial amphibole grains, which commonly merge with a coarse spongy intergrowth of amphibole with quartz and/or albite (most likely replacing omphacite); and a fine-grained symplectite of low-Na clinopyroxene with sodic plagioclase and minor hornblende invading omphacite. Many specimens show these varieties as a sequence, inferred to reflect decreasing pressure (and ultimately, temperature). Amphibole compositions cover a wide range: the most sodic occur in large interstitial grains and fall near the junction of the winchite, barroisite and taramite fields of the IMA classification; they trend towards a pargasitic hornblende, still with significant glaucophane component; spongy amphiboles typically lie on a trend towards lower glaucophane component; symplectite amphibole is generally a common hornblende on a typical

  18. A Study on Reactive Spray Deposition Technology Processing Parameters in the Context of Pt Nanoparticle Formation

    Science.gov (United States)

    Roller, Justin M.; Maric, Radenka

    2015-12-01

    Catalytic materials are complex systems in which achieving the desired properties (i.e., activity, selectivity and stability) depends on exploiting the many degrees of freedom in surface and bulk composition, geometry, and defects. Flame aerosol synthesis is a process for producing nanoparticles with ample processing parameter space to tune the desired properties. Flame dynamics inside the reactor are determined by the input process variables such as solubility of precursor in the fuel; solvent boiling point; reactant flow rate and concentration; flow rates of air, fuel and the carrier gas; and the burner geometry. In this study, the processing parameters for reactive spray deposition technology, a flame-based synthesis method, are systematically evaluated to understand the residence times, reactant mixing, and temperature profiles of flames used in the synthesis of Pt nanoparticles. This provides a framework for further study and modeling. The flame temperature and length are also studied as a function of O2 and fuel flow rates.

  19. The influence of interface exchange coupling on the demagnetization process for perpendicularly oriented FePt/α-Fe/FePt trilayers

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The influence of the interface exchange coupling on the magnetization reversal process for a FePt/α-Fe/FePt tri-layer structure has been studied through a micromagnetic approach.The analytical formula of the nucleation field has been derived.It is found that the nucleation field increases as the interface coupling constant rises.Especially when the thickness of the soft layer is small,the influence of the exchange coupling on the nucleation field is significant.The angular distributions of the magnetization for various exchange coupling constants have been obtained by numerical calculation.It is found that the angular distribution of the magnetization is discontinuous at the interface of the hard and soft layers.In the meantime,the pinning field decreases with the increase of the thickness of the soft layer and the exchange coupling constant.

  20. Involving Program Constituencies in the Evaluation Process.

    Science.gov (United States)

    Deshler, David

    1984-01-01

    Two case studies provide examples of citizen and program participant involvement in program evaluation. The Reflective Appraisal of Programs at Cornell Cooperative Extension involves volunteer interviewers of participants; the Lancaster County (Pennsylvania) Office of Mental Health/Mental Retardation is reviewed by a volunteer citizens' committee.…

  1. Defining stakeholder involvement in participatory design processes

    NARCIS (Netherlands)

    Vink, P.; Imada, A.S.; Zink, K.J.

    2008-01-01

    A participatory approach could be used to implement work place or organizational improvements. However, the question is which participants should be involved and how. In this paper the theoretical involvement in different steps of a linear stepwise approach is described and compared with the latest

  2. Defining stakeholder involvement in participatory design processes

    NARCIS (Netherlands)

    Vink, P.; Imada, A.S.; Zink, K.J.

    2008-01-01

    A participatory approach could be used to implement work place or organizational improvements. However, the question is which participants should be involved and how. In this paper the theoretical involvement in different steps of a linear stepwise approach is described and compared with the latest

  3. Synthesis and composition evolution of bimetallic Pd Pt alloy nanoparticles

    Science.gov (United States)

    Ren, Guoqiang; Shi, Honglan; Xing, Yangchuan

    2007-09-01

    This paper reports a study on the synthesis of Pd-Pt alloy nanoparticles and composition evolution of the alloys. The synthesis involves Pd and Pt acetylacetonate as the metal precursors and trioctylphosphine (TOP) as the solvent. Thermal decomposition of the Pd-TOP complex resulted in Pd nanoparticles, while substitution of Pt in the Pt-TOP complex by Pd allowed formation of the Pd-Pt alloys. It was observed that the Pd-Pt nanoparticles formed at the very beginning in the synthesis process are Pd rich with various nanoparticle sizes ranging from 1.5 to 25 nm in diameter. These nanoparticles averaged out through a digestive ripening process and reached a final size of 3.5 nm in about 10 min. The alloy compositions evolved throughout the synthesis process and only reached the preset Pd to Pt ratio of the precursors in 120 min. It was found that Pt acetylacetonate alone in TOP cannot produce Pt nanoparticles, which was attributed to the formation of a Pt-TOP complex and a strong coordination of Pt to the phosphine. This observation led us to propose an atomic exchange process between the Pt-TOP complex and the Pd atoms at the nanoparticle surface. As a result, the alloy formation process is limited by a substitution and diffusion rate of the Pt atoms at the surface of the alloy nanoparticles.

  4. ANALISIS KINERJA PROSES LATEX DIPPING MENGGUNAKAN TEKNIK CAPABILITY PROCESS (STUDI KASUS: PT DHARMA MEDIPRO

    Directory of Open Access Journals (Sweden)

    Yona Maimury

    2016-01-01

    Full Text Available The quality of product is reflected from the performance of its process. The most frequent issue that occurs in local company today -- is -- most company only focuses on the output regardless the process. It causes the difficulty that occurs in local company to compete with other company in global environment. One of the local companies that has their business shifting up significantly, with the great number of export target and actual export, is PT Dharma Medipro, which has many processes on the production of sphygmomanometer. One of the processes that critical to quality is latex dipping process, where the yield of this process that must be considered is the thickness of the bag component. In order to improve the process, we should first establish the measurement of process performance using capability process technique, which is one of the tools came from statistical process control method. The result indicates that the process is unstable with the value of capability indices Cp = 4,69 ; Cpk = -0,77 ; Cpu = -0,77 ; Cpl = 10,15 ; and Cpm = 0,28, moreover the number of part per million (PPM that out of the spesification limit reach 912.500 units.

  5. The SHORT-ROOT-like gene PtSHR2B is involved in Populus phellogen activity.

    Science.gov (United States)

    Miguel, Andreia; Milhinhos, Ana; Novák, Ondřej; Jones, Brian; Miguel, Célia M

    2016-03-01

    SHORT-ROOT (SHR) is a GRAS transcription factor first characterized for its role in the specification of the stem cell niche and radial patterning in Arabidopsis thaliana (At) roots. Three SHR-like genes have been identified in Populus trichocarpa (Pt). PtSHR1 shares high similarity with AtSHR over the entire length of the coding sequence. The two other Populus SHR-like genes, PtSHR2A and PtSHR2B, are shorter in their 5' ends when compared with AtSHR. Unlike PtSHR1, that is expressed throughout the cambial zone of greenhouse-grown Populus trees, PtSHR2Bprom:uidA expression was detected in the phellogen. Additionally, PtSHR1 and PtSHR2B expression patterns markedly differ in the shoot apex and roots of in vitro plants. Transgenic hybrid aspen expressing PtSHR2B under the 35S constitutive promoter showed overall reduced tree growth while the proportion of bark increased relative to the wood. Reverse transcription-quantitative PCR (RT-qPCR) revealed increased transcript levels of cytokinin metabolism and response-related genes in the transgenic plants consistent with an increase of total cytokinin levels. This was confirmed by cytokinin quantification by LC-MS/MS. Our results indicate that PtSHR2B appears to function in the phellogen and therefore in the regulation of phellem and periderm formation, possibly acting through modulation of cytokinin homeostasis. Furthermore, this work points to a functional diversification of SHR after the divergence of the Populus and Arabidopsis lineages. This finding may contribute to selection and breeding strategies of cork oak in which, unlike Populus, the phellogen is active throughout the entire tree lifespan, being at the basis of a highly profitable cork industry.

  6. Pt/Ti/n-InP nonalloyed ohmic contacts formed by rapid thermal processing

    Science.gov (United States)

    Katz, A.; Weir, B. E.; Chu, S. N. G.; Thomas, P. M.; Soler, M.; Boone, T.; Dautremont-Smith, W. C.

    1990-04-01

    Low resistance nonalloyed ohmic contacts of e-gun evaporated Pt/Ti to S doped n-InP 5×1017, 1×1018, and 5×1018 cm-3 have been fabricated by rapid thermal processing. The contacts to the lower doped substrates (5×1017 and 1×1018 cm-3) were rectifying as-deposited as well as after heat treatment at temperatures lower than 350 °C. Higher processing temperatures stimulated the Schottky to ohmic contact conversion with minimum specific contact resistance of 1.5×10-5 and 5×10-6 Ω cm2, respectively, as a result of rapid thermal processing at 450 °C for 30 s. Heating at a temperature of 550 °C again yielded a Schottky contact. The contact to the 5×1018 cm-3 InP was ohmic as deposited with a specific contact resistance value of 1.1×10-4 Ω cm2. Supplying heat treatment to the contact caused a decrease of the specific contact resistance to a minimum of 8×10-7 Ω cm2 as a result of rapid thermal processing at 450 °C for 30 s. In all cases, this heat treatment caused a limited interfacial reactions between the Ti and the InP, and resulted in an almost abrupt interface. Heating at temperatures higher than 500 °C resulted in an interfacial intermixing and a mutual migration and reaction of the Ti and the semiconductor elements. The Pt/Ti bilayer structure was highly tensile as deposited (5×109 dyn cm-2) and became stress-free as a result of the interfacial reactions which took place while heating the samples to temperature of 400 °C or higher.

  7. Involvement of Women In Community Development Process In ...

    African Journals Online (AJOL)

    Involvement of Women In Community Development Process In Ikeduru Local Government Area Of Imo State. ... between 31 and 40 years majority (47%) had primary education, majority (73.64%) were not involved in decision making process ...

  8. Pt-Ru Catalysts Prepared by a Modified Polyol Process for Direct Methanol Fuel Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junmin; ZHU Fangfang; ZHANG Kunhua; LIU Weiping; GUAN Weiming

    2012-01-01

    Supported PtRu/C catalysts used in direct methanol fuel cells (DMFCs) were prepared by a new modified polyol method.Transmission electron microscopy (TEM),X-ray diffraction (XRD) and cyclic voltammograms (CVs) were carried out to characterize the morphology,composition and the electrochemical properties of the PtRu/C catalyst.The results revealed that the PtRu nanoparticles with small average particle size (≈2.5 nm),and highly dispersed on the carbon support.The PtRu/C catalyst exhibited high catalytic activity and anti-poisoned performance than that of the JM PtRu/C.It is imply that the modified polyol method is efficient for PtRu/C catalyst preparation.

  9. The Processes Involved in Designing Software.

    Science.gov (United States)

    1980-08-01

    body of relevant knowledge. There has been a limited amount of research on the process of design or on problems that are difficult enough to require the...refinement of those subproblems. Our results are therefore potentially limited to similar straightforward problems. In tasks for which the...They first break the problem Into Its major constituents, thus forming a solution moodl . During each Iteration, subproblems from the previous cycle are

  10. Artificial concurrent catalytic processes involving enzymes.

    Science.gov (United States)

    Köhler, Valentin; Turner, Nicholas J

    2015-01-11

    The concurrent operation of multiple catalysts can lead to enhanced reaction features including (i) simultaneous linear multi-step transformations in a single reaction flask (ii) the control of intermediate equilibria (iii) stereoconvergent transformations (iv) rapid processing of labile reaction products. Enzymes occupy a prominent position for the development of such processes, due to their high potential compatibility with other biocatalysts. Genes for different enzymes can be co-expressed to reconstruct natural or construct artificial pathways and applied in the form of engineered whole cell biocatalysts to carry out complex transformations or, alternatively, the enzymes can be combined in vitro after isolation. Moreover, enzyme variants provide a wider substrate scope for a given reaction and often display altered selectivities and specificities. Man-made transition metal catalysts and engineered or artificial metalloenzymes also widen the range of reactivities and catalysed reactions that are potentially employable. Cascades for simultaneous cofactor or co-substrate regeneration or co-product removal are now firmly established. Many applications of more ambitious concurrent cascade catalysis are only just beginning to appear in the literature. The current review presents some of the most recent examples, with an emphasis on the combination of transition metal with enzymatic catalysis and aims to encourage researchers to contribute to this emerging field.

  11. SISTEM PERHITUNGAN HARGA POKOK PRODUKSI PADA PERUSAHAAN FARMASI PT. BALATIF DENGAN METODE PROCESS COSTING

    Directory of Open Access Journals (Sweden)

    Andreas Handojo

    2009-01-01

    Full Text Available Nowadays, PT. Balatif has the calculation system for production cost that can only include the calculation of cost of materials based on standard Bill of Material (BOM, while record of factory overhead cost, direct labor cost and report that relating to the calculation of Cost of Goods Manufactured of product still cannot be handled by the system. So that the current costs that really occurred in the production process will be difficult to trace and the production cost not based on reality process. Based on that problem, this research design a system to calculate production cost that can handle that problem. This application used Microsoft Visual Studio .Net 2005 as the programming tool and Oracle 10g as the database. Results that obtained from the application that have been made are raw material usage can be saved based on BOM or additional, machine usage, operator usage, and so on associated with the production process. In addition, the application that has been made can be used to allocate the costs that occur during the production process and to generate reports related to the calculation of Cost of Goods Manufactured of a product automatically.

  12. Redox chemistry of H[sub 2]S oxidation by the British Gas Stretford Process. Pt. 3; Electrochemical behaviour of anthraquinone 2,7 disulphonate in alkaline electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, G.H.; Thompson, I. (Imperial College, London (United Kingdom). Dept. of Mineral Resources Engineering)

    1993-04-01

    Electrochemical reduction of aqueous anthraquinone 2,7 disulphonate (AQ27DS) solutions at pH 9.3 were studied at Hg, Au and Pt electrodes. Cyclic voltammograms showed about 40 mV potential separation of the single pair of current peaks, precluding a simple one or two electron process. Charge measurements in controlled potential exhaustive reductions indicated a 2 mol e[sup -] per mol AQ27DS process leading to quinolate anions, whereas the partially reduced solution showed an EPR spectrum, indicating the presence of radical species, which, if produced directly, would involve only a 1 mol e[sup -] per mol AQ27DS process. The results are congruous with a reduction mechanism involving an initial 2 mol e[sup -] per mol AQ27DS process to give anthraquinolate anions, from which electron transfer in solution to AQ27DS species produced AQ27DS[center dot][sup -] radical anions (a comproportionation). (author)

  13. Steam reforming of glycerol over Pt-MCM-41 synthesized in a one-step process

    Science.gov (United States)

    Zhang, Xiao-Hui; Yan, Feng-Wen; Guo, Cun-Yue; Yuan, Guo-Qing

    2012-12-01

    Pt-MCM-41 materials were synthesized by a simple method via simultaneous self-assembling and Pt incorporation using cetyltrimethylammonium chloride (CTAC) as a structure directing agent. Structural characterization of the sample was carried out by N2 sorption, XRD and TEM measurements. The highly ordered structure of MCM-41 was not appreciably affected by the formation of the Pt particles. Unlike related results, the Pt nanoparticles were incorporated into the mesopores and embedded into the pore walls as framework. The Pt-MCM-41 sample was tested as a catalyst in the steam reforming of glycerol in which it exhibited moderate activity, high selectivity to hydrogen, and very low selectivity to light alkanes.

  14. The effect of performance agreement, employee involvement, facilitation, assessment and feedback towards employee performance: a study in Pt. Surya Pamenang, Jawa Timur Province, Indonesia

    OpenAIRE

    ANSORY AL FADJAR; SALIM UBUD; SUDIRO ACHMAD; KHUSNIAH NUR

    2016-01-01

    Facing ASEAN Economic Community to deal with foreign companies from various countries needs optimal resources so that local enterprises could increase the employee performance. This study aims to analyze the influence of performance agreement, facilitation, assessment, feedback, employee involvement towards employee performance. The inferential statistical analysis used was SEM (Structural Equation Modeling) by collecting data through a survey at PT. Surya Pamenang, Kediri, Jawa Timur Provinc...

  15. Pt(II) coordination complexes as visible light photocatalysts for the oxidation of sulfides using batch and flow processes

    OpenAIRE

    Casado-Sánchez, A.; Gómez-Ballesteros, R.; Tato, F.; Soriano, F.J.; Pascual-Coca, G.; Cabrera, S.; J. Alemán

    2016-01-01

    A new catalytic system for the photooxidation of sulfides based on Pt(ii) complexes is presented. The catalyst is capable of oxidizing a large number of sulfides containing aryl, alkyl, allyl, benzyl, as well as more complex structures such as heterocycles and methionine amino acid, with complete chemoselectivity. In addition, the first sulfur oxidation in a continuous flow process has been developed

  16. Determinants of prognosis in breast cancer patients with tumor involvement of the skin (pT4b).

    NARCIS (Netherlands)

    Wieland, A.W.; Louwman, M.W.; Voogd, A.C.; Beek, M.W. van; Vreugdenhil, G.R.; Roumen, R.M.H.

    2004-01-01

    Determinants of prognosis were studied in patients with breast cancer with histologically proven tumor extension to the skin without clinical evidence of distant metastases (i.e., pT4b N0-3 M0). Data were collected retrospectively on 77 consecutive patients diagnosed in one community teaching hospit

  17. Determinants of prognosis in breast cancer patients with tumor involvement of the skin (pT4b).

    NARCIS (Netherlands)

    Wieland, A.W.; Louwman, M.W.; Voogd, A.C.; Beek, M.W. van; Vreugdenhil, G.R.; Roumen, R.M.H.

    2004-01-01

    Determinants of prognosis were studied in patients with breast cancer with histologically proven tumor extension to the skin without clinical evidence of distant metastases (i.e., pT4b N0-3 M0). Data were collected retrospectively on 77 consecutive patients diagnosed in one community teaching

  18. High Work Output Ni-Ti-Pt High Temperature Shape Memory Alloys and Associated Processing Methods

    Science.gov (United States)

    Noebe, Ronald D. (Inventor); Draper, Susan L. (Inventor); Nathal, Michael V. (Inventor); Garg, Anita (Inventor)

    2009-01-01

    According to the invention, compositions of Ni-Ti-Pt high temperature, high force, shape memory alloys are disclosed that have transition temperatures above 100 C.; have narrow hysteresis; and produce a high specific work output.

  19. Processing Time for Initial Disability Cases Involving the Processing Centers

    Data.gov (United States)

    Social Security Administration — The dataset includes annual data for average processing time and counts of initial disability claims in which there was a medical determination made broken out by...

  20. Pt-Re-Sn/Al{sub 2}O{sub 3} trimetallic catalysts for naphtha reforming processes without presulfiding step

    Energy Technology Data Exchange (ETDEWEB)

    Mazzieri, V.A.; Grau, J.M.; Vera, C.R.; Yori, J.C.; Parera, J.M.; Pieck, C.L. [Instituto de Investigaciones en Catalisis y Petroquimica, INCAPE, FIQ-UNL, CONICET, Santiago del Estero 2654, 3000 Santa Fe (Argentina)

    2005-12-12

    The n-heptane reforming and the cyclopentane hydrogenolysis reactions over noble metal monometallic catalysts (0.3% Pt), bimetallic catalysts (0.3% Pt, x% Re, x=0.1, 0.3, 0.9 and 2.0, sulfided) and trimetallic catalysts (0.3% Pt, 0.3% Re, y% Sn, y=0.1, 0.3, 0.6 and 0.9, unsulfided) were studied. The metal function was supported over a chlorided {gamma}-alumina that provided the acid function. The reforming of n-heptane was performed at 450{sup o}C, molar ratio H{sub 2}/n-C{sub 7}=4 and WHSV=7.3 while the hydrogenolysis of cyclopentane was performed at 350{sup o}C, H{sub 2}/CP=20 and WHSV=2.4. The sulfided 0.3Pt-0.3Re catalyst (with 0.06% S) was found to be the best performing bimetallic one. It had a great stability, typical of this kind of catalysts, and also produced a reformate with a high iso-heptanes/toluene ratio. This is advantageous for fulfilling the current environmental regulations that limit the amount of aromatic hydrocarbons in reformulated gasolines. The best trimetallic catalyst was 0.3Pt-0.3Re-0.6Sn which had a similar activity and selectivity as sulfided 0.3Pt-0.3Re, though it displayed a higher stability and a lower hydrogenolysis activity, without the need of presulfidation. Tin affected the metal and acid functions of the catalyst simultaneously and inhibited them to such different degrees that a very convenient metal/acid activity ratio was obtained, resulting in an improvement of the activity, selectivity and stability of the catalysts. It can be concluded that it is possible to prepare trimetallic naphtha reforming catalysts of the Pt-Re-Sn kind with a better performance than conventional sulfided Pt-Re catalysts and with the additional advantage that they do not need complicated sulfiding pretreatments. This simplifies the commercial operation of the reformer unit and enables the application of this catalyst to continuously operated processes.

  1. Transmission electron microscopy investigation of Pt/Ba0.7Sr0.3TiO3/Pt capacitors with different annealing processes

    NARCIS (Netherlands)

    Qin, Y.L.; Jia, C.L.; Liedtke, R.; Waser, R.; Urban, K.

    2003-01-01

    The effects of postannealing in oxygen ambient and forming gas atmosphere (FGA) on the microstructure and chemistry of Pt/Ba0.7Sr0.3TiO3 (BST)/Pt capacitors prepared by chemical solution deposition have been investigated by means of transmission electron microscopy. The as-deposited film layers of t

  2. Democratizing Process Innovation? On Citizen Involvement in Public Sector BPM

    Science.gov (United States)

    Niehaves, Björn; Malsch, Robert

    ‘Open Innovation’ has been heavily discussed for product innovations; however, an information systems (IS) perspective on ‘process innovation’ has not yet been taken. Analyzing the example of the public sector in Germany, the paper seeks to investigate the factors that hinder and support ‘open process innovation’, a concept we define as the involvement of citizens in business process management (BPM) activities. With the help of a quantitative study (n=358), six factors are examined for their impact on citizen involvement in local government BPM initiatives. The results show that citizen involvement in reform processes is not primarily motivated by the aim of cost reduction, but rather related to legitimacy reasons and the intent to increase employee motivation. Based on these findings, implications for (design) theory and practice are discussed: Instead of detailed collaborative business processes modeling, the key of citizen involvement in public sector BPM lies in communication and mutual understanding.

  3. Electroless Pt deposition on Mn3O4 nanoparticles via the galvanic replacement process: electrocatalytic nanocomposite with enhanced performance for oxygen reduction reaction.

    Science.gov (United States)

    Kim, Ki Woong; Kim, Soo Min; Choi, Suhee; Kim, Jongwon; Lee, In Su

    2012-06-26

    A novel electroless Pt deposition method was exploited by employing the galvanic replacement process occurring between the Mn(3)O(4) surface and PtCl(4)(2-) complexes. The newly discovered process provides a simple protocol to produce the catalytic nanocomposite, in which a high density of ultrafine Pt nanocrystals is stably immobilized in a homogeneously dispersive state on the surface of Mn(3)O(4) nanoparticles. When the eletrocatalytic activity was tested for the oxygen reduction reaction, which limits the rate of the overall process in proton-exchange membrane fuel cells, the resulting Pt/Mn(3)O(4) nanocomposite showed highly enhanced specific activity and durability, compared with those of the commercial Pt/C catalyst.

  4. The Appropriateness Of Parental Involvement In The Job Search Process

    Directory of Open Access Journals (Sweden)

    Gary S. Insch

    2011-01-01

    Full Text Available This paper explores millennial job seekers and their parental involvement in the job search process. Preliminary work on a scale to measure the “appropriateness” of certain job search behaviors is reported. Ten parental job search behaviors are identified.  The appropriateness constructs of “mentoring” and “meddling” are developed and empirically tested. Results indicate that both meddling and mentoring are valid and initially useful constructs in examining the suitability of parental involvement in the job search process. The possible impact of parental involvement in the job search process is then discussed along with possible managerial responses.

  5. Processing of Ni30Pt20Ti50 High-Temperature Shape-Memory Alloy Into Thin Rod Demonstrated

    Science.gov (United States)

    Noebe, Ronald D.; Draper, Susan L.; Biles, Tiffany A.; Leonhardt, Todd

    2005-01-01

    High-temperature shape-memory alloys (HTSMAs) based on nickel-titanium (NiTi) with significant ternary additions of palladium (Pd), platinum (Pt), gold (Au), or hafnium (Hf) have been identified as potential high-temperature actuator materials for use up to 500 C. These materials provide an enabling technology for the development of "smart structures" used to control the noise, emissions, or efficiency of gas turbine engines. The demand for these high-temperature versions of conventional shape-memory alloys also has been growing in the automotive, process control, and energy industries. However these materials, including the NiPtTi alloys being developed at the NASA Glenn Research Center, will never find widespread acceptance unless they can be readily processed into useable forms.

  6. ANALISIS PEMILIHAN PERANGKAT LUNAK SISTEM ENTERPRISE RESOURCE PLANNING (ERP MENGGUNAKAN ANALYTICAL HIERARCHY PROCESS (AHP: STUDI KASUS PADA PT CILIANDRA PERKASA

    Directory of Open Access Journals (Sweden)

    Roni Kurniawan

    2011-11-01

    Full Text Available Enterprise Resource Planning (ERP can be described as a concept for planning and managing organization resources to create value added for stakeholders. PT Ciliandra Perkasa as an agribusiness company realized the importance of ERP system to support their operational activities. Indeed, there are many problems on the ERP implementation. Therefore, it is needed to build a proper ERP system process to be implemented. This issue will be the research problem. Implementing a qualitative method, this research uses primary data and secondary data as samples. Tests and analysis use Analytical Hierarchical Process (AHP which its results are expected to guide the management of PT Ciliandra Perkasa in selecting proper software of ERP application.

  7. Kenyan nurses involvement in national policy development processes.

    Science.gov (United States)

    Juma, Pamela Atieno; Edwards, Nancy; Spitzer, Denise

    2014-01-01

    The aim of this study was to critically examine how nurses have been involved in national policy processes in the Kenyan health sector. The paper reports qualitative results from a larger mixed method study. National nonnursing decision-makers and nurse leaders, and provincial managers as well as frontline nurse managers from two Kenyan districts were purposefully selected for interviews. Interviews dealt with nurses' involvement in national policy processes, factors hindering nurses' engagement in policy processes, and ways to enhance nurses' involvement in policy processes. Critical theory and feminist perspectives guided the study process. Content analysis of data was conducted. Findings revealed that nurses' involvement in policy processes in Kenya was limited. Only a few nurse leaders were involved in national policy committees as a result of their positions in the sector. Critical analysis of the findings revealed that hierarchies and structural factors as well as nursing professional issues were the primary barriers constraining nurses' involvement in policy processes. Thus, there is need to address these factors both by nurses themselves and by nonnursing decision makers, in order to enhance nurses engagement in policy making and further the contribution to quality of services to the communities.

  8. Constraints on the Higgs Sector from Processes Involving Photons

    OpenAIRE

    Krawczyk,Maria

    1998-01-01

    The Higgs sector of the Standard Model and of the Two Higgs Doublet Extensions of SM, MSSM and the general 2HDM, can be tested in processes involving photons. A short review of the corresponding results is presented.

  9. Asymmetric bipolar resistive switching in solution-processed Pt/TiO{sub 2}/W devices

    Energy Technology Data Exchange (ETDEWEB)

    Biju, Kuyyadi P; Bourim, El Mostafa; Hwang, Hyunsang [Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712 (Korea, Republic of); Liu, XinJun; Kim, Insung; Jung, Seungjae; Siddik, Manzar; Lee, Joonmyoung, E-mail: biju@gist.ac.k, E-mail: hwanghs@gist.ac.k [School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712 (Korea, Republic of)

    2010-12-15

    The resistive switching characteristics of Pt/TiO{sub 2}/W devices in a submicrometre via-hole structure are investigated. TiO{sub 2} film is grown by the sol-gel spin coating technique. The device exhibits reversible and reproducible bistable resistive switching with a rectifying effect. The Schottky contact at the Pt/TiO{sub 2} interface limits electron injection under reverse bias resulting in a rectification ratio of >60 at 2 V in the low-resistance state. The switching mechanism in our device can be interpreted as an anion migration-induced redox reaction at the tungsten bottom electrode (W). The rectifying effect can significantly reduce the sneak path current in a crossbar array and provide a feasible way to achieve high memory density.

  10. Angular dependence of demagnetization processes in Fe-FePt perpendicular exchange-spring bilayers

    Energy Technology Data Exchange (ETDEWEB)

    Solzi, M. [Dipartimento di Fisica, Universita di Parma and CNISM, V.le G.P. Usberti 7/A, 43100 Parma (Italy)]. E-mail: solzi@fis.unipr.it; Pernechele, C. [Dipartimento di Fisica, Universita di Parma and CNISM, V.le G.P. Usberti 7/A, 43100 Parma (Italy); Pellicelli, R. [Dipartimento di Fisica, Universita di Parma and CNISM, V.le G.P. Usberti 7/A, 43100 Parma (Italy); Ghidini, M. [Dipartimento di Fisica, Universita di Parma and CNISM, V.le G.P. Usberti 7/A, 43100 Parma (Italy); Albertini, F. [IMEM-CNR, Parco Area delle Scienze 37/A, 43010 Parma (Italy); Casoli, F. [IMEM-CNR, Parco Area delle Scienze 37/A, 43010 Parma (Italy)

    2007-09-15

    The angular dependence of hysteresis loops of exchange-spring (ES) bilayers constituted by a Fe layer as the soft phase and a hard layer of L1{sub 0} Fe{sub 53}Pt{sub 47} is presented. FePt thin films of nominal thickness 10 nm have been prepared by RF sputtering on MgO (1 0 0) substrates in order to achieve the epitaxial growth with the c-axis perpendicular to the film plane. The Fe soft layers have been deposited at RT with various thicknesses (from 2 to 10 nm). The angular dependence of the bilayers' magnetic properties is studied by SQUID magnetometry varying the angle between the easy axis of the hard phase and the direction of the applied field from 0 to {pi}/2. The magnetic behavior at different angles is analyzed by a one-dimensional micromagnetic model specifically extended to the case of perpendicular magnetic anisotropy (PMA)

  11. MR urography in children. Pt. 2. How to use ImageJ MR urography processing software

    Energy Technology Data Exchange (ETDEWEB)

    Vivier, Pierre-Hugues; Dacher, Jean-Nicolas [University Hospital of Rouen, Department of Radiology, Rouen (France); University of Rouen, LITIS Laboratory EA 4108, School of Medicine and Pharmacy, Rouen (France); Dolores, Michael [University Hospital of Rouen, Department of Radiology, Rouen (France); Taylor, Melissa [Department of Paediatrics, Ambroise Pare Hospital, Boulogne Billancourt (France)

    2010-05-15

    MR urography (MRU) is an emerging technique particularly useful in paediatric uroradiology. The most common indication is the investigation of hydronephrosis. Combined static and dynamic contrast-enhanced MRU (DCE-MRU) provides both morphological and functional information in a single examination. However, specific post-processing must be performed and to our knowledge, dedicated software is not available in conventional workstations. Investigators involved in MRU classically use homemade software that is not freely accessible. For these reasons, we have developed a software program that is freely downloadable on the National Institute of Health (NIH) website. We report and describe in this study the features of this software program. (orig.)

  12. Design of Low Pt Concentration Electrocatalyst Surfaces with High Oxygen Reduction Reaction Activity Promoted by Formation of a Heterogeneous Interface between Pt and CeO(x) Nanowire.

    Science.gov (United States)

    Chauhan, Shipra; Mori, Toshiyuki; Masuda, Takuya; Ueda, Shigenori; Richards, Gary J; Hill, Jonathan P; Ariga, Katsuhiko; Isaka, Noriko; Auchterlonie, Graeme; Drennan, John

    2016-04-13

    Pt-CeO(x) nanowire (NW)/C electrocatalysts for the improvement of oxygen reduction reaction (ORR) activity on Pt were prepared by a combined process involving precipitation and coimpregnation. A low, 5 wt % Pt-loaded CeO(x) NW/C electrocatalyst, pretreated by an optimized electrochemical conditioning process, exhibited high ORR activity over a commercially available 20 wt % Pt/C electrocatalyst although the ORR activity observed for a 5 wt % Pt-loaded CeO(x) nanoparticle (NP)/C was similar to that of 20 wt % Pt/C. To investigate the role of a CeO(x) NW promotor on the enhancement of ORR activity on Pt, the Pt-CeO(x) NW interface was characterized by using hard X-ray photoelectron spectroscopy (HXPS), transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS). Microanalytical data obtained by these methods were discussed in relation to atomistic simulation performed on the interface structures. The combined techniques of HXPS, TEM-EELS, and atomistic simulation indicate that the Pt-CeO(x) NW interface in the electrocatalyst contains two different defect clusters: Frenkel defect clusters (i.e., 2Pt(i)(••) - 4O(i)″ - 4V(o)(••) - V(Ce)″″) formed in the surface around the Pt-CeO(x) NW interface and Schottky defect clusters (i.e., (Pt(Ce)″ - 2V(O)(••) - 2Ce(Ce)') and (Pt(Ce)″ - V(O)(••))) which appear in the bulk of the Pt-CeO(x) NW interface similarly to Pt-CeO(x) NP/C. It is concluded that the formation of both Frenkel defect clusters and Schottky defect clusters at the Pt-CeO(x) NW heterointerface contributes to the promotion of ORR activity and permits the use of lower Pt-loadings in these electrocatalysts.

  13. Publication process involving the discovery of artemisinin (qinghaosu) before 1985

    Institute of Scientific and Technical Information of China (English)

    Man-Yuan Wang

    2016-01-01

    All the original references were provided by the Nobel Laureate Youyou Tu. The publication process involving the discovery of artemisinin was collected and sorted by her first Ph D student, Associate Professor Man-Yuan Wang. Through the publication of this article, the journal expects to provide a reference to the scientists who dedicated to the research of artemisinin, especially those who are interested in the discovery process of artemisinin.

  14. Wet chemical synthesis of intermetallic Pt3Zn nanocrystals via weak reduction reaction together with UPD process and their excellent electrocatalytic performances

    Science.gov (United States)

    Chen, Qiaoli; Zhang, Jiawei; Jia, Yanyan; Jiang, Zhiyuan; Xie, Zhaoxiong; Zheng, Lansun

    2014-05-01

    Platinum based alloy nanocrystals are promising catalysts for a variety of important practical process. However, it remains a great challenge to synthesize platinum-based intermetallic compound nanocrystals with well-defined surface structures. In this communication, taking the synthesis of concave cubic intermetallic Pt3Zn nanocrystals with {hk0} facets as an example, we proposed a new synthesis strategy for intermetallic compounds by reduction of noble metal precursors via a slow reduction process and reduction of transition metal ions via an underpotential deposition (UPD) process in wet chemical synthesis. The as-prepared intermetallic Pt3Zn nanocrystals exhibited superior CO poisoning tolerance and high electro-catalytic activity in both methanol and formic acid oxidation reactions in comparison with solid solution Pt3Zn nanocrystals and Pt/C.Platinum based alloy nanocrystals are promising catalysts for a variety of important practical process. However, it remains a great challenge to synthesize platinum-based intermetallic compound nanocrystals with well-defined surface structures. In this communication, taking the synthesis of concave cubic intermetallic Pt3Zn nanocrystals with {hk0} facets as an example, we proposed a new synthesis strategy for intermetallic compounds by reduction of noble metal precursors via a slow reduction process and reduction of transition metal ions via an underpotential deposition (UPD) process in wet chemical synthesis. The as-prepared intermetallic Pt3Zn nanocrystals exhibited superior CO poisoning tolerance and high electro-catalytic activity in both methanol and formic acid oxidation reactions in comparison with solid solution Pt3Zn nanocrystals and Pt/C. Electronic supplementary information (ESI) available: Additional characterization data. See DOI: 10.1039/c4nr00313f

  15. Involvement of external stakeholders in local Health policymaking process

    DEFF Research Database (Denmark)

    Eklund Karlsson, Leena; Jakobsen, Mette Winge; Winblad Heiberg, Malin

    2017-01-01

    Collaboration between research and policy is an essential element for knowledge-based public health. However, only half of the Danish municipalities have experience with collaborating with researchers or other stakeholders. Through content analysis of interviews and policy documents the study exp...... influence on the involvement of external stakeholders, allowing only a few to contribute in a closed policymaking process....

  16. Analysis of bilinear stochastic systems. [involving multiplicative noise processes

    Science.gov (United States)

    Willsky, A. S.; Marcus, S. I.; Martin, D. N.

    1974-01-01

    Analysis of stochastic dynamical systems that involve multiplicative (bilinear) noise processes is considered. After defining the systems of interest, the evolution of the moments of such systems, the question of stochastic stability, and estimation for bilinear stochastic systems are discussed. Both exact and approximate methods of analysis are introduced, and, in particular, the uses of Lie-theoretic concepts and harmonic analysis are discussed.

  17. A Process Model of Organizational Commitment and Job Involvement.

    Science.gov (United States)

    1982-09-01

    AD-A123 043 A PROCESS MODEL OF ORGANIZATIONAL COMMITMENT AND JOB I INVOLVEMENT(U) AIR FORCE INST OF TECH WR IGHT PATTERSON AFB OH SCHOL OF SYSTEMS...Appo @1 inu pubo 01004 Aocesston For NTIS CRA&I DTIC TAB Unannounced 0I Justfication - gI, Distr" ’ut ioi / Af t A PROCESS MODEL OF ORGANIZATIONAL...GOVT ACCESSION NO. 3. RECIPIENT’S CATALOG NUMBER LSSR 76-82 1,3b - 4. TITLE (and Subtitle) S. TYPE OF REPORT & PERIOD COVERED A PROCESS MODEL OF

  18. Comparing the electrical characteristics and reliabilities of BJTs and MOSFETs between Pt and Ti contact silicide processes

    Science.gov (United States)

    Liu, Kaiping; Shang, Ling

    1999-08-01

    The sub-threshold characteristics and the reliability of BJTs, using platinum contact silicide (PtSi) or titanium contact silicide (TiSi2), are compared and analyzed. During processing, it is observed that the TiSi2 process produces higher interface state density (Dit) than the PtSi process. The increase in Dit not only leads to a higher base current in the BJTs, but also leads to a lower transconductance for the MOS transistors. The data also show that the impact on NPN and nMOS is more severe than the impact of PNP and pMOS, respectively. This can be explained by the non-symmetric interface state distribution, the re- activation of boron, and/or by substrate trap centers. The amount of interface states produced depends not only on the thickness of the titanium film deposited, but also on the temperature and duration of the titanium silicide process. The electrical data indicates that after all the Back-End- Of-The-Line processing steps, which includes a forming gas anneal, Dit is still higher on wafers with the TiSi2 transistor's base current increases at different rates between the two processes, but eventually levels off to the same final value. However, the PNP transistor's base current increases at approximately the same rate, but eventually levels off at different final values. These indicate that the TiSi2 process may have modified the silicon and oxygen dangling bond structure during its high temperature process in addition to removing the hydrogen from the passivated interface states.

  19. Application of PT9800 software to optimization of carburizing process for heavy-duty locomotive gear%PT9800软件在重载机车齿轮渗碳工艺优化中的应用

    Institute of Scientific and Technical Information of China (English)

    文超; 董雯; 谭小明; 王晓华

    2012-01-01

    利用PT9800软件进行了两段式渗碳工艺强扩比的模拟计算,据此优化了重载机车齿轮渗碳工艺并节省了20%的工艺时间。相应的验证试验也获得了满意的渗层金相组织、硬度梯度和预期的渗碳层深度,证明了PT9800计算的准确性,从而为渗碳工艺强扩比的合理选择和优化提供了依据。%The carburizing-diffusion ratio of two-stage carburizing technology was simulated by using PT9800 software.According to this simulation calculation,the carburizing process for heavy-duty locomotive gear was optimized and the process time was saved 20%.The expected microstructure,hardness distribution and case depth of the carburized layer were obtained by the relevant experiments,it is approved the reasonability and accuracy of PT9800 software,and provides evidence for choice and optimization of the carburizing-diffusion ratio.

  20. Molecular dynamic simulation study of plasma etching L10 FePt media in embedded mask patterning (EMP process

    Directory of Open Access Journals (Sweden)

    Jianxin Zhu

    2017-05-01

    Full Text Available Plasma etching process of single-crystal L10-FePt media [H. Wang et al., Appl. Phys. Lett. 102(5 (2013] is studied using molecular dynamic simulation. Embedded-Atom Method [M. S. Daw and M. I. Baskes, Phy. Rev. B 29, 6443 (1984; X. W. Zhou, R. A. Johnson and H. N. G. Wadley, Phy. Rev. B 69, 144113 (2004] is used to calculate the interatomic potential within atoms in FePt alloy, and ZBL potential [J.F. Ziegler, J. P. Biersack and U. Littmark, “The Stopping and Range of Ions in Matter,” Volume 1, Pergamon,1985] in comparison with conventional Lennard-Jones “12-6” potential is applied to interactions between etching gas ions and metal atoms. It is shown the post-etch structure defects can include amorphized surface layer and lattice interstitial point defects that caused by etchant ions passed through the surface layer. We show that the amorphized or damaged FePt lattice surface layer (or “magnetic dead-layer” thickness after etching increases with ion energy for Ar ion impacts, but significantly small for He ions at up to 250eV ion energy. However, we showed that He sputtering creates more interstitial defects at lower energy levels and defects are deeper below the surface compared to Ar sputtering. We also calculate the interstitial defect level and depth as dependence on ion energy for both Ar and He ions. Media magnetic property loss due to these defects is also discussed.

  1. Investigating Individuals' Intention to be Involved in Knowledge Management Process

    Directory of Open Access Journals (Sweden)

    M. J.M. Razi

    2011-01-01

    Full Text Available Problem statement: Implementation of Knowledge Management (KM process in organizations is considered as essential to be competitive in the present competitive world. Though the modern KM practices highly depend on technology, individuals (‘organizational members’ intention to be involved in KM process plays a major role in the success. Hence, the evaluation of individuals’ intention is deemed as significant before the actual implementation of KM process in organizations. Nevertheless, inadequate information is presented in this regard; as a result, a wide research gap prevails in the literature. In this context, the present study focuses on developing a research frame work that can be used to measure the individual intention to be involved in KM process. Approach: Subsequent to a critical analysis of the research gaps, a basic research model has been developed based on knowledge creation theory, KM enablers, and individual acceptance model. Measurers and questionnaire items were identified for each variable from relevant literature. Consequently, the reliability of the instrument was tested among academic staff of a Malaysian university. Results: The Cronbach’s alpha for each variable is more than 0.800 that exhibits the reliability of the instruments. Conclusion: The presented research framework might be a doorstep for future study in this area of KM. Moreover, practitioners may use the proposed framework to measure the intention of individuals to be involved in KM process before actually embarking to it. However, the framework and the model should be tested in different socio cultural and organizational climate to make it robust.

  2. EARLY READING ASSESSMENT INSTRUMENTS: ABILITIES AND PROCESSES INVOLVED

    Directory of Open Access Journals (Sweden)

    Ana Cláudia de Souza

    2017-04-01

    Full Text Available This study investigates the following early reading assessment instruments: “Bateria de Recepção e Produção da Linguagem Verbal” (SCLIAR-CABRAL, 2003a and “Teste de Competência de Leitura de Palavras e Pseudopalavras” (SEABRA; CAPOVILLA, 2010. The main research goal is to analyze in each one of these reading assessment instruments some of the multiple cognitive processes and basic low-level abilities involved in reading. In this sense, decoding, word recognition, lexical access, syntactic and textual processing, and comprehension are the cognitive processes taken into account. With regard to the basic reading abilities, accuracy and fluency (rhythm, prosody and speed are considered. The results indicate that each one of the analyzed reading assessment instruments assesses different aspects of the reading processes and abilities, mainly through off-line measures. ScliarCabral’s assessment battery allows the researcher or the teacher to evaluate the following processes: perception of the grapheme opposition in minimal pairs of words and in sentences, difficulties in sentence processing, skills in decoding the graphemic-phonemic relationship, and textual comprehension. In its turn, the reading assessment instrument proposed by Seabra e Capovilla allows one to evaluate student’s reading development level, by classifying the kind of processing as logographic, alphabetic or orthographic.

  3. Peritrophin-like protein from Litopenaeus vannamei (LvPT) involved in white spot syndrome virus (WSSV) infection in digestive tract challenged with reverse gavage

    Science.gov (United States)

    Xie, Shijun; Li, Fuhua; Zhang, Xiaojun; Zhang, Jiquan; Xiang, Jianhai

    2017-05-01

    The peritrophic membrane plays an important role in the defense system of the arthropod gut. The digestive tract is considered one of the major tissues targeted by white spot syndrome virus (WSSV) in shrimp. In this study, the nucleotide sequence encoding peritrophin-like protein of Litopenaeus vannamei (LvPT) was amplified from a yeast two-hybrid library of L. vannamei. The epitope peptide of LvPT was predicted with the GenScript OptimumAntigen™ design tool. An anti-LvPT polyclonal antibody was produced and shown to specifically bind a band at 27 kDa, identified as LvPT. The LvPT protein was expressed and its concentration determined. LvPT dsRNA (4 μg per shrimp) was used to inhibit LvPT expression in shrimp, and a WSSV challenge experiment was then performed with reverse gavage. The pleopods, stomachs, and guts were collected from the shrimp at 0, 24, 48, and 72 h post-infection (hpi). Viral load quantification showed that the levels of WSSV were significantly lower in the pleopods, stomachs, and guts of shrimp after LvPT dsRNA interference than in those of the controls at 48 and 72 hpi. Our results imply that LvPT plays an important role during WSSV infection of the digestive tract.

  4. WORKING POSTURE ANALYSIS AND DESIGN USING RULA (RAPID UPPER LIMB ASSESSMENT METHOD IN PRODUCTION PROCESS AT PT. INDANA PAINT

    Directory of Open Access Journals (Sweden)

    Yongky Kusnandar Djiono

    2013-12-01

    Full Text Available Working posture can affect the comfort and productivity of labor in doing manual work. In this study, RULA method is used to determine the risk level of musculoskeletal disorders (MSDs injury in the production process at PT. Indana Paint (consists of mixing and packaging steps for water-based paint, solvent-based paint, and base paint production, and then given proposed improvements to reduce the risk level. Method used in this research is direct observation and video recording of every work element to determine some awkward postures that will be assessed using RULA method. Thirty awkward postures are found, there are 7 working posture (23.3% have low risk level, 11 working posture (36.7% have medium risk level, and 12 working posture (40% have high risk level. Proposed improvements given is to brief the workers on appropriate lifting technique and working methods, adding mechanical aids for handling drums, and working position height adjustment.

  5. Modeling supercritical fluid extraction process involving solute-solid interaction

    Energy Technology Data Exchange (ETDEWEB)

    Goto, M.; Roy, B. Kodama, A.; Hirose, T. [Kumamoto Univ., Kumamoto (Japan)

    1998-04-01

    Extraction or leaching of solute from natural solid material is a mass transfer process involving dissolution or release of solutes from a solid matrix. Interaction between the solute and solid matrix often influences the supercritical fluid extraction process. A model accounting for the solute-solid interaction as well as mass transfer is developed. The BET equation is used to incorporate the interaction and the solubility of solutes into the local equilibrium in the model. Experimental data for the supercritical extraction of essential oil and cuticular wax from peppermint leaves are successfully analyzed by the model. The effects of parameters on the extraction behavior are demonstrated to illustrate the concept of the model. 18 refs., 5 figs., 1 tab.

  6. Atmospheric-Pressure Plasma Jet Processed Pt-Decorated Reduced Graphene Oxides for Counter-Electrodes of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ting-Hao Wan

    2016-10-01

    Full Text Available Ultrafast atmospheric-pressure plasma jet (APPJ processed Pt-decorated reduced graphene oxides (rGOs were used as counter-electrodes in dye-sensitized solar cells (DSSCs. Pastes containing rGO, ethyl cellulose, terpineol, and chloroplatinic acid were screen-printed and sintered by nitrogen dc-pulse APPJs. Pt nanodots were uniformly distributed on the rGO flakes. When using Pt-decorated rGOs as the counter electrodes of DSSCs, the efficiency of the DSSC first increased and then decreased as the APPJ processing time increased. Nitrogen APPJs can effectively remove organic binders and can reduce chloroplatinic acid to Pt, thereby improving the efficiency of DSSCs. However, over-calcination by APPJ can damage the graphenes and degrade the DSSCs. The addition of Pt mainly improves the fill factor, which thereby increases the efficiency of DSSCs. The optimized APPJ processing time was merely 9 s owing to the vigorous interaction among the rGOs, chloroplatinic acid and nitrogen APPJs.

  7. Understanding the cognitive processes involved in writing to learn.

    Science.gov (United States)

    Arnold, Kathleen M; Umanath, Sharda; Thio, Kara; Reilly, Walter B; McDaniel, Mark A; Marsh, Elizabeth J

    2017-06-01

    Writing is often used as a tool for learning. However, empirical support for the benefits of writing-to-learn is mixed, likely because the literature conflates diverse activities (e.g., summaries, term papers) under the single umbrella of writing-to-learn. Following recent trends in the writing-to-learn literature, the authors focus on the underlying cognitive processes. They draw on the largely independent writing-to-learn and cognitive psychology learning literatures to identify important cognitive processes. The current experiment examines learning from 3 writing tasks (and 1 nonwriting control), with an emphasis on whether or not the tasks engaged retrieval. Tasks that engaged retrieval (essay writing and free recall) led to better final test performance than those that did not (note taking and highlighting). Individual differences in structure building (the ability to construct mental representations of narratives; Gernsbacher, Varner, & Faust, 1990) modified this effect; skilled structure builders benefited more from essay writing and free recall than did less skilled structure builders. Further, more essay-like responses led to better performance, implicating the importance of additional cognitive processes such as reorganization and elaboration. The results highlight how both task instructions and individual differences affect the cognitive processes involved when writing-to-learn, with consequences for the effectiveness of the learning strategy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. Aggression proneness: Transdiagnostic processes involving negative valence and cognitive systems.

    Science.gov (United States)

    Verona, Edelyn; Bresin, Konrad

    2015-11-01

    Aggressive behavior is observed in persons with various mental health problems and has been studied from the perspectives of neuroscience and psychophysiology. The present research reviews some of the extant experimental literature to help clarify the interplay between domains of functioning implicated in aggression proneness. We then convey a process-oriented model that elucidates how the interplay of the Negative Valence and Cognitive System domains of NIMH's Research Domain Criteria (RDoC) helps explain aggression proneness, particularly reactive aggression. Finally, we report on a study involving event-related potential (ERP) indices of emotional and inhibitory control processing during an emotional-linguistic go/no-go task among 67 individuals with histories of violence and criminal offending (30% female, 44% African-American) who reported on their aggressive tendencies using the Buss-Perry Aggression Questionnaire. Results provide evidence that tendencies toward angry and aggressive behavior relate to reduced inhibitory control processing (no-go P3) specifically during relevant threat-word blocks, suggesting deterioration of cognitive control by acute or sustained threat sensitivity. These findings highlight the value of ERP methodologies for clarifying the interplay of Negative Valence and Cognitive System processes in aggression proneness.

  9. Nonlinear switching and solitons in PT-symmetric photonic systems

    CERN Document Server

    Suchkov, Sergey V; Huang, Jiahao; Dmitriev, Sergey V; Lee, Chaohong; Kivshar, Yuri S

    2015-01-01

    One of the challenges of the modern photonics is to develop all-optical devices enabling increased speed and energy efficiency for transmitting and processing information on an optical chip. It is believed that the recently suggested Parity-Time (PT) symmetric photonic systems with alternating regions of gain and loss can bring novel functionalities. In such systems, losses are as important as gain and, depending on the structural parameters, gain compensates losses. Generally, PT systems demonstrate nontrivial non-conservative wave interactions and phase transitions, which can be employed for signal filtering and switching, opening new prospects for active control of light. In this review, we discuss a broad range of problems involving nonlinear PT-symmetric photonic systems with an intensity-dependent refractive index. Nonlinearity in such PT symmetric systems provides a basis for many effects such as the formation of localized modes, nonlinearly-induced PT-symmetry breaking, and all-optical switching. Nonl...

  10. Sensing Magnetic Directions in Birds: Radical Pair Processes Involving Cryptochrome

    Directory of Open Access Journals (Sweden)

    Roswitha Wiltschko

    2014-07-01

    Full Text Available Birds can use the geomagnetic field for compass orientation. Behavioral experiments, mostly with migrating passerines, revealed three characteristics of the avian magnetic compass: (1 it works spontaneously only in a narrow functional window around the intensity of the ambient magnetic field, but can adapt to other intensities, (2 it is an “inclination compass”, not based on the polarity of the magnetic field, but the axial course of the field lines, and (3 it requires short-wavelength light from UV to 565 nm Green. The Radical Pair-Model of magnetoreception can explain these properties by proposing spin-chemical processes in photopigments as underlying mechanism. Applying radio frequency fields, a diagnostic tool for radical pair processes, supports an involvement of a radical pair mechanism in avian magnetoreception: added to the geomagnetic field, they disrupted orientation, presumably by interfering with the receptive processes. Cryptochromes have been suggested as receptor molecules. Cry1a is found in the eyes of birds, where it is located at the membranes of the disks in the outer segments of the UV-cones in chickens and robins. Immuno-histochemical studies show that it is activated by the wavelengths of light that allow magnetic compass orientation in birds.

  11. Sensing magnetic directions in birds: radical pair processes involving cryptochrome.

    Science.gov (United States)

    Wiltschko, Roswitha; Wiltschko, Wolfgang

    2014-09-01

    Birds can use the geomagnetic field for compass orientation. Behavioral experiments, mostly with migrating passerines, revealed three characteristics of the avian magnetic compass: (1) it works spontaneously only in a narrow functional window around the intensity of the ambient magnetic field, but can adapt to other intensities, (2) it is an "inclination compass", not based on the polarity of the magnetic field, but the axial course of the field lines, and (3) it requires short-wavelength light from UV to 565 nm Green. The Radical Pair-Model of magnetoreception can explain these properties by proposing spin-chemical processes in photopigments as underlying mechanism. Applying radio frequency fields, a diagnostic tool for radical pair processes, supports an involvement of a radical pair mechanism in avian magnetoreception: added to the geomagnetic field, they disrupted orientation, presumably by interfering with the receptive processes. Cryptochromes have been suggested as receptor molecules. Cry1a is found in the eyes of birds, where it is located at the membranes of the disks in the outer segments of the UV-cones in chickens and robins. Immuno-histochemical studies show that it is activated by the wavelengths of light that allow magnetic compass orientation in birds.

  12. Availability (energetic) analysis of coal gasification process. Pt. 1. Theoretical considerations

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, P.; Conger, W.L.

    1981-10-01

    The concepts of availability, energy, and of exergetic efficiency are developed for use in evaluating coal gasification processes. The problem of defining the thermodynamic surroundings is discussed, and the approach of Bosnjakovic is used to select surroundings. In the second paper in this series the analysis is illustrated by applying it in evaluating the Synthane Gasification process. (13 refs.)

  13. [Proteins of human milk involved in immunological processes].

    Science.gov (United States)

    Lis, Jolanta; Orczyk-Pawiłowicz, Magdalena; Kątnik-Prastowska, Iwona

    2013-05-31

    Human milk contains a lot of components (i.e. proteins, carbohydrates, lipids, inorganic elements) which provide basic nutrients for infants during the first period of their lives. Qualitative composition of milk components of healthy mothers is similar, but their levels change during lactation stages. Colostrum is the fluid secreted during the first days postpartum by mammary epithelial cells. Colostrum is replaced by transitional milk during 5-15 days postpartum and from 15 days postpartum mature milk is produced. Human milk, apart from nutritional components, is a source of biologically active molecules, i.e. immunoglobulins, growth factors, cytokines, acute phase proteins, antiviral and antibacterial proteins. Such components of human milk are responsible for specific biological activities of human milk. This secretion plays an important role in growth and development of newborns. Bioactive molecules present in the milk support the immature immune system of the newborn and also protect against the development of infection. In this article we describe the pathways involved in the production and secretion of human milk, the state of knowledge on the proteome of human milk, and the contents of components of milk during lactation. Moreover, some growth factors and proteins involved in innate and specific immunity, intercellular communication, immunomodulation, and inflammatory processes have been characterized.

  14. Proteins of human milk involved in immunological processes 

    Directory of Open Access Journals (Sweden)

    Jolanta Lis

    2013-05-01

    Full Text Available Human milk contains a lot of components (i.e. proteins, carbohydrates, lipids, inorganic elements which provide basic nutrients for infants during the first period of their lives. Qualitative composition of milk components of healthy mothers is similar, but their levels change during lactation stages. Colostrum is the fluid secreted during the first days postpartum by mammary epithelial cells. Colostrum is replaced by transitional milk during 5-15 days postpartum and from 15 days postpartum mature milk is produced. Human milk, apart from nutritional components, is a source of biologically active molecules, i.e. immunoglobulins, growth factors, cytokines, acute phase proteins, antiviral and antibacterial proteins. Such components of human milk are responsible for specific biological activities of human milk. This secretion plays an important role in growth and development of newborns. Bioactive molecules present in the milk support the immature immune system of the newborn and also protect against the development of infection. In this article we describe the pathways involved in the production and secretion of human milk, the state of knowledge on the proteome of human milk, and the contents of components of milk during lactation. Moreover, some growth factors and proteins involved in innate and specific immunity, intercellular communication, immunomodulation, and inflammatory processes have been characterized.

  15. Collision processes of hydrocarbon species in hydrogen plasmas. Pt. 3. The Silane-family

    CERN Document Server

    Janev, R K

    2003-01-01

    Cross sections are provided for most important collision processes of the Silicon-Hydrides from the ''Silane-family'': SiH sub y (y = 1 - 4) molecules and their ions SiH sub y sup + , with (plasma) electrons and protons. The processes include: electron impact ionization and dissociation of SiH sub y , dissociative excitation, ionization and recombination of SiH sub y sup + ions with electrons, and charge - and atom - exchange in proton collisions with SiH sub y. All important channels of dissociative processes are considered. Information is also provided on the energetics (reactants/products energy loss / gain) of each individual reaction channel. Total and partial cross sections are presented in compact analytic forms. The critical assessment of data, derivation of new data and presentation of results follow closely the concepts of the recently published related databases for Carbon-Hydrides, namely for the Methane family, and for the Ethane- and the Propane families, respectively.

  16. Study of the Isothermal Oxidation Process and Phase Transformations in B2-(Ni,PtAl/RENE-N5 System

    Directory of Open Access Journals (Sweden)

    Luis Alberto Cáceres-Díaz

    2016-09-01

    Full Text Available Changes in composition, crystal structure and phase transformations of B2-(Ni,PtAl coatings upon isothermal oxidation experiments (natural and scale free oxidation at 1100 °C, as a function of time beyond their martensitic transformation, are reported. Specifically, the analysis of lattice parameter and composition are performed to identify changes in the B2-(Ni,PtAl phase upon the chemically-driven L10-(Ni,PtAl and L12-(Ni,Pt3Al transformations. The B2-(Ni,PtAl phase was found to disorder and transform the martensite during the heat treatments for both oxidation experiments at approximately 36.3 and 40.9 at. % of Al, 47.7 and 42.9 at. % of Ni, 6.2 and 8.5 at. % of Pt, 4.2 and 2.9 at. % of Cr and 4.4 and 3.8 at. % of Co. The lattice constant and the long-range order parameter of the B2-(Ni,PtAl phase decreased linearly as a function of the elemental content irrespective of the nature of the oxidation experiments.

  17. The removal of Microcystis ichthyoblabe cells and its hepatotoxin microcystin-LR during electrooxidation process using Pt/Ti electrodes.

    Science.gov (United States)

    Jeon, Bong-Seok; Han, Jisun; Kim, Seog-Ku; Oh, Hye-Cheol; Park, Ho-Dong

    2015-01-01

    Electrooxidation is widely used to remove harmful organic and inorganic substances as well as pathogenic microorganisms. This study investigates the removal of Microcystis ichthyoblabe cells and their hepatotoxin microcystin-LR by the electrooxidation process using Pt/Ti electrodes. Additionally, the morphology changes and cell sizes were determined by scanning electron microscopy and a particle size analyzer, respectively. The algal cells were severely damaged by the electrooxidation process. During the initial treatment, intracellular microcystin-LR was released from the cells, increasing the extracellular microcystin-LR concentration. The electrooxidation charge required to remove cells and MC-LR was 3 × 10(4) C and 6 × 10(4) C, respectively. The removal efficiencies of M. ichthyoblabe cells and microcystin-LR were insensitive to initial cell density, initial microcystin-LR concentration and solution conductivity, but were heavily reduced at large algal suspension volume. Therefore, to achieve simultaneous removal of Microcystis cells and their MC, it is necessary to control the volume of algal suspension.

  18. Characterization of azo dyes on Pt and Pt/polyaniline/dispersed Pt electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Molina, J.; Fernandez, J.; Rio, A.I. del; Bonastre, J. [Departamento de Ingenieria Textil y Papelera, EPS de Alcoy, Universitat Politecnica de Valencia, Plaza Ferrandiz y Carbonell s/n, 03801 Alcoy (Spain); Cases, F., E-mail: fjcases@txp.upv.es [Departamento de Ingenieria Textil y Papelera, EPS de Alcoy, Universitat Politecnica de Valencia, Plaza Ferrandiz y Carbonell s/n, 03801 Alcoy (Spain)

    2012-06-15

    The electrochemical characterization of two organic dyes (amaranth and procion orange MX-2R) has been performed on Pt electrodes and Pt electrodes coated with polyaniline and dispersed Pt. Electrodes with different Pt loads have been synthesized and characterized obtaining that a load of 300 {mu}g cm{sup -2} was the optimum one. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) was employed to observe the distribution and morphology of the Pt nanoparticles. The electroactivity of the electrodes has also been characterized by means of scanning electrochemical microscopy (SECM). The chemical characterization of Pt dispersed Pani coated Pt electrodes (Pt-Pani-Pt) was performed by means of X-ray photoelectron spectroscopy (XPS). The electrochemical characterization of the dyes has been performed by means of cyclic voltammetry. Voltammograms have shown that the presence of the dyes diminishes characteristic Pt oxidation and reduction peaks. However, redox processes due to the dyes, appeared in the voltammograms. The different species responsible of these redox processes were generated in the vicinity of the electrode and were not adsorbed on the electrode surface since after stirring, the different redox processes disappeared. Characterization with different scan rates showed that redox processes of both dyes were controlled by diffusion.

  19. Combustion of spent shales from the Rotem deposit. Pt. 1. Concurrent thermal processes: Pyrolysis and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Zabicky, J. (Ben-Gurion Univ. of the Negev, Beersheba (Israel). Institutes for Applied Research Ben-Gurion Univ. of the Negev, Beersheba (Israel). M.R. Bloch Center for Coal Research); Wohlfarth, A. (Pama - Energy Resources Development Ltd., Arava (Israel))

    1991-06-01

    Spent shales prepared by the Fisher method from oil shales of the Rotem deposit/Israel were studied in a continuous fluidized bed reactor at 700-900deg C under atmospheric pressure, using mixtures of nitrogen and carbon dioxide as the fluidizing gas. A set of simultaneus processes takes place, including pyrolysis of the organic residue in the spent shales, decomposition of calcium carbonate, dehydration of clay phases, decomposition of pyrites, reduction of anhydrite to calcium sulfide and other minor reactions. An important secondary process is gasification of the organic residue by carbon dioxide produced by carbonate decomposition or combustion. The extent to which these reactions take place depends on temperature, composition of the fluidizing gas, particle size of the spent shales, and mean residence time of the particles in the reactor. (orig.).

  20. Studies on sweet potatoes. Pt. 1. Changes in the carbohydrates during processing

    Energy Technology Data Exchange (ETDEWEB)

    Susheelamma, N.S.; Changala Reddy, G.; Rukmani, C.S.; Tharanathan, R.N. (Central Food Technological Research Inst., Mysore (India). Dept. of Food Chemistry)

    1992-05-01

    The qualitative and quantitative changes in the nature of different carbohydrate fractions of sweet potatoes (hard and soft cooking types), after dry (baking and toasting) and wet (steaming) processing have been studied. Maltose, glucose and fructose were the predominant sugars in the ethanol soluble fraction. The total sugar and amylose contents significantly decreased in the ethanol insoluble residues. This was supported by the decrease in blue value and the absorption maxima of the iodine complex. (orig.).

  1. Influences of pH value in deposition-precipitation synthesis process on Pt-doped TiO2 catalysts for photocatalytic oxidation of NO

    Institute of Scientific and Technical Information of China (English)

    Shuzhen Song; Zhongyi Sheng; Yue Liu; Haiqiang Wang; Zhongbiao Wu

    2012-01-01

    This work has been undertaken to study the influences of pH value on the characteristics and activity of photocatalyst by deposition-precipitation method during its preparation process.A series of Pt-modified TiO2 were prepared by deposition-precipitation method at different pH values as well as wet impregnation method,and characterized by XRD,XPS,TEM,UV-Vis and photoluminescence(PL).It was found that the catalysts had the highest photocatalytic activity for NO conversion when pH value was kept at around 7.And the sample prepared by deposition-precipitation method showed higher activity than that by impregnation method.This was mainly due to their high value in highly-dispersed platinum oxides(PtOx)content on the surface of the catalysts.The results from UV-Vis absorption showed that highest absorbance was obtained for Pt/TiO2 prepared at pH values of around 7.And PL spectra results indicated that the recombination rate of photogenerated electrons and holes of the samples prepared by deposition-precipitation method was lower than that prepared by impregnation method.And in the zeta potential study,the pH values for the isoelectric point of the preparing slurry of 0.05 wt.%Pt/TiO2 and 0.5 wt.%Pt/TiO2 were determined to be 6.5-8.5,which further confirmed the enrichment of PtOx dopants for the catalysts repapered when pH value was around 7.

  2. PT. Tira Austenite, Tbk dan Analisis Kinerja Perusahaan Ekspedisi dalam Perspektif Supply Chain dan Metode Analytic Network Process (ANP

    Directory of Open Access Journals (Sweden)

    Khristian Edi Nugroho Soebandrija

    2015-06-01

    Full Text Available PT. TIRA AUSTENITE, Tbk (PTATbk and other companies in the field of supply chain require coordination pertaining cross functional and cross collaboration. The mentioned collaboration is required especially for Expedition Company. The performance analysis of Expedition Company, including PTATbk is needed to face the global competition. Company contribution generally, and in particular for Empirical Study toward PTATBK can lead to the problem solving and performance improvement, which covers selecting optimal expedition company and efficient time to dispatch product from existing route to be integrated into the core essence of this research pertaining PTATbk. The mentioned research refers to Empirical Study dan Managerial Implications through books and journals as reference in the Research Methodology. The focus of this researchmethodology is the Analytic Network Process (ANP; criteria of Price and Service; and other important criteria that support the performance analysis within PTATbk. Software ARENA Simulation plays vital role in this research that has the conclusion and recommendation toward problem solving and performance improvement that are translated into benefits versus risks and its form of % and the currency of IDR and/or USD.

  3. IAEA-MEL case studies. Pt.1. Source terms and transport processes

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, M.S. [International Atomic Energy Agency, Monaco (Monaco). Marine Environmental Laboratory

    1997-12-31

    This IAEA review summarises the nuclide inventory and process-related aspects of investigations at sites which include disposals and dispersions of radioactive waste in the Arctic Seas, N.E. Atlantic Ocean, Far Eastern Seas and the Irish Sea, accidental inputs to the Norwegian Sea and Sea of Okhotsk, releases from weapons test environments in the Pacific Ocean and fallout from the Chernobyl accident, particularly in the Baltic and Black Seas. In many of these cases, monitoring, behavioural and modelling studies have been carried out. The Monaco laboratory is using natural and man-made radionuclides to trace particle flux and sedimentation, particularly in S.E. Asia and the Mediterranean Sea. A perspective on the results of these studies has been maintained in a new and growing marine radioactivity database which will soon be available to Member States. Radiological conclusions can be compared to the recently published results of a coordinated research programme organised by IAEA-MEL on sources of radioactivity in the marine environment and their relative contributions to overall dose assessment from marine radioactivity (the MARDOS project). Finally, some future plans within the IAEA-MEL programme are outlined. For example, the Government of Japan is funding a strategically planned follow-up to the Geosecs programme to update information on open ocean radionuclide distributions. Additional IAEA funds have also been allocated for study of marine inputs of technologically enhanced natural radionuclides from the oil and phosphogypsum industries. The laboratory is also developing and applying in-situ monitoring techniques for continuous and ROV-mounted surveys of radionuclide inventories in water and sediment. The presentation will end with a call for participation in an IAEA Symposium on Marine Pollution, containing various sessions related to tracer and radiological aspects of marine radioactivity, to be held in Monaco in 1998 as part of the United Nations programme

  4. Staff Involvement and the Public Library Planning Process.

    Science.gov (United States)

    Stephens, Annabel K.

    1989-01-01

    Reports the results of a study of two library systems' differing approaches to staff involvement in library planning. The systems' attempts to prepare staff members, keep them informed, and encourage staff participation are described, and the resulting benefits are contrasted. Suggestions for successful staff involvement are offered. (34…

  5. Metal nanostructures with complex surface morphology: The case of supported lumpy Pd and Pt nanoparticles produced by laser processing of metal films

    Science.gov (United States)

    Ruffino, F.; Maugeri, P.; Cacciato, G.; Zimbone, M.; Grimaldi, M. G.

    2016-09-01

    photothermal vaporization and Coulomb explosion processes of the Pd and Pt nanoparticles are invoked as possible mechanisms for the lumpy nanoparticles formation.

  6. EFEKTIVITAS IMPLEMENTASI CORPORATE SOCIAL RESPOSIBILITY PT. ABC

    Directory of Open Access Journals (Sweden)

    Rizkiaji Rikky Djunaedi

    2015-12-01

    Full Text Available The purposes of this study were 1 to analyze public perceptions on the effectiveness of the implementation of CSR of PT. A B C; 2 to analyze the implementation of CSR activities by PT. A B C; 3 to formulate strategies to improve the effectiveness of the implementation of CSR of PT. A B C. The method used in this research was descriptive analysis with a survey approach to measure expectations and performance assessment on the CSR implemented programs by the public, and there were respondents 104 respondents involved in this study. This study used the Importance-Performance Analysis (IPA aiming to determine the effectiveness of the programs that have been implemented and to map the relationship between the expectations and the performance of each variable. Furthermore, using a SWOT analysis of the data processing and of the objectives of the program made by CSR is expected to provide recommendations to develop strategies in order to increase the effectiveness of CSR program of ABC Company.Keywords: corporate social responsibility (CSR, mining industry, implementation analysis, IPA, SWOTAbstrakTujuan dari  penelitian ini adalah 1 menganalisis persepsi masyarakat teradap efektivitas implementasi CSR PT. ABC; 2 menganalisis pelaksanaan  kegiatan CSR oleh PT. ABC; 3 merumuskan strategi untuk meningkatkan efektivitas implementasi CSR PT. ABC. Metode yang digunakan dalam penelitian ini adalah analisis deskriptif dengan pendekatan survey untuk mengukur harapan dan penilaian kinerja oleh masyarakat atas program CSR yang diterapkan. Jumlah responden sebanyak 104 orang.  Dalam penelitian ini digunakan Analisis Importance-Performance Analysis (IPA bertujuan untuk mengetahui efektifitas dari program-program yang telah dijalankan serta  memetakan hubungan antara harapan dengan kinerja dari masing-masing variabel. Selanjutnya menggunakan analisis SWOT dari hasil pengolahan data dan dari tujuan program dibuat oleh CSR sehingga dapat memberikan rekomendasi

  7. Systematic Integrated Process Design and Control of Reactive Distillation Processes Involving Multi-elements

    DEFF Research Database (Denmark)

    Mansouri, Seyed Soheil; Sales-Cruz, Mauricio; Huusom, Jakob Kjøbsted

    2016-01-01

    In this work, integrated process design and control of reactive distillation processes that involve multiple elements (more than two) is addressed through a computer-aided hierarchical decomposition-based framework. Multiple elements are encountered for reactive systems when four or more compounds...... (including inert compounds) are encountered. The reactive distillation design methods and tools which are similar in concept to design of binary non-reactive distillations and binary reactive distillations are used for design of multi-element reactive distillation processes, such as driving force approach...

  8. Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly report, April 1-June 30, 1980. [Pt/Pd

    Energy Technology Data Exchange (ETDEWEB)

    Yarrington, R M; Feins, I R; Hwang, H S

    1980-07-01

    Phase II of the contract, which involved catalyst preparation and evaluation, was nearly completed this quarter. Phase III, which calls for the design and construction of a fuel processor, was started. During the quarter, four types of tests were run on the small scale catalyst screening unit. The operating line for coke-free operations was found to be approximately between 0.41 to 0.44 O/sub 2//C level. Screening at lower O/sub 2//C levels led to problems with plugging. In other tests, increased severity for screening steam reforming catalysts was obtained by doubling the space velocity. Another series of tests were run to determine the gas composition from the catalytic partial oxidation (CPO) section and to evaluate two CPO catalysts. In the other series of tests, catalysts were aged for about 20 hours using a propane, steam, and air mixture before testing with No. 2 oil for another five hours. This latter test has been used to study Pt/Rh catalysts made with various supports. Differences were readily determined for Pt/Rh supported on alpha alumina and Pt/Rh supported on stabilized alumina. This test method will find continued use in evaluating metal-support interactions. Several samples must be evaluated by this method before aging runs are made in the larger unit. After leaching alumina from a used Pt/Rh catalyst, the x-ray diffraction pattern showed the presence of a Pt-Rh alloy in the metal residue. Experiments were run to show that the alloy was formed in the reactor during testing and not during catalyst preparation. A larger version of the ATR reactor has been designed and major components are on order. Completion of the construction phase is scheduled for the next quarter.

  9. Atomic-level Pd-Pt alloying and largely enhanced hydrogen-storage capacity in bimetallic nanoparticles reconstructed from core/shell structure by a process of hydrogen absorption/desorption.

    Science.gov (United States)

    Kobayashi, Hirokazu; Yamauchi, Miho; Kitagawa, Hiroshi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki

    2010-04-28

    We have achieved the creation of a solid-solution alloy where Pd and Pt are homogeneously mixed at the atomic level, by a process of hydrogen absorption/desorption as a trigger for core (Pd)/shell (Pt) nanoparticles. The structural change from core/shell to solid solution has been confirmed by in situ powder X-ray diffraction, energy dispersive spectra, solid-state (2)H NMR measurement, and hydrogen pressure-composition isotherms. The successfully obtained Pd-Pt solid-solution nanoparticles with a Pt content of 8-21 atom % had a higher hydrogen-storage capacity than Pd nanoparticles. Moreover, the hydrogen-storage capacity of Pd-Pt solid-solution nanoparticles can be tuned by changing the composition of Pd and Pt.

  10. Risk Mapping of Bogie S2HD-9C Production Process that Take Effect on Production Fulfillment at PT. Barata Indonesia (Persero

    Directory of Open Access Journals (Sweden)

    Faza Yoshio Susanto

    2017-01-01

    Full Text Available PT Barata Indonesia (Persero is one of leading metal works company in Indonesia. It has 3 main business line which are engineering procurement and construction (EPC, industrial tools manufacturing, and foundry. As the company’s strategic objective in delivering quality product and service to the customer, PT Barata Indonesia should maintain their production process properly. One of the featured product of PT Barata Indonesia is bogie. The production process of bogie shows a fluctuative delivery fulfillment. It can be proved by the contract amendment information. Risk management can be used as the method to manage risk inside the production process of bogie. Therefore, this research is aimed to identify risks that may occur from each activities of bogie S2HD-9C’s production process. The risk identification is done by using fault tree analysis method in order to determine the root cause of each activity performed. The risk evaluation is done by using FMEA method which can classify the effects of failure based on the severity and occurrence of failure. Then continue to the risk mapping and risk mitigation determination for bogie S2HD-9C’s production process. Loss that caused by the emergence of risk also determined using value at risk method. Moreover, risk profile dashboard will be provided as the tools in managing risk.

  11. Binuclear Pt-Tl bonded complex with square pyramidal coordination around Pt: a combined multinuclear NMR, EXAFS, UV-Vis, and DFT/TDDFT study in dimethylsulfoxide solution.

    Science.gov (United States)

    Purgel, Mihály; Maliarik, Mikhail; Glaser, Julius; Platas-Iglesias, Carlos; Persson, Ingmar; Tóth, Imre

    2011-07-04

    The structure and bonding of a new Pt-Tl bonded complex formed in dimethylsulfoxide (dmso), (CN)(4)Pt-Tl(dmso)(5)(+), have been studied by multinuclear NMR and UV-vis spectroscopies, and EXAFS measurements in combination with density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. This complex is formed following the equilibrium reaction Pt(CN)(4)(2-) + Tl(dmso)(6)(3+) ⇆ (CN)(4)Pt-Tl(dmso)(5)(+) + dmso. The stability constant of the Pt-Tl bonded species, as determined using (13)C NMR spectroscopy, amounts to log K = 2.9 ± 0.2. The (NC)(4)Pt-Tl(dmso)(5)(+) species constitutes the first example of a Pt-Tl bonded cyanide complex in which the sixth coordination position around Pt (in trans with respect to the Tl atom) is not occupied. The spectral parameters confirm the formation of the metal-metal bond, but differ substantially from those measured earlier in aqueous solution for complexes (CN)(5)Pt-Tl(CN)(n)(H(2)O)(x)(n-) (n = 0-3). The (205) Tl NMR chemical shift, δ = 75 ppm, is at extraordinary high field, while spin-spin coupling constant, (1)J(Pt-Tl) = 93 kHz, is the largest measured to date for a Pt-Tl bond in the absence of supporting bridging ligands. The absorption spectrum is dominated by two strong absorption bands in the UV region that are assigned to MMCT (Pt → Tl) and LMCT (dmso → Tl) bands, respectively, on the basis of MO and TDDFT calculations. The solution of the complex has a bright yellow color as a result of a shoulder present on the low energy side of the band at 355 nm. The geometry of the (CN)(4)Pt-Tl core can be elucidated from NMR data, but the particular stoichiometry and structure involving the dmso ligands are established by using Tl and Pt L(III)-edge EXAFS measurements. The Pt-Tl bond distance is 2.67(1) Å, the Tl-O bond distance is 2.282(6) Å, and the Pt-C-N entity is linear with Pt-C and Pt···N distances amounting to 1.969(6) and 3.096(6) Å, respectively. Geometry optimizations on

  12. Interactive methods to involve users into workspace design process

    DEFF Research Database (Denmark)

    Souza da Conceição, Carolina; Broberg, Ole; Banke, Palle

    2013-01-01

    This paper addresses the question of whether the use of a combination of interactive methods involving workers can lead to a useful input to the (re)design of their workspace. The workbook and the layout design game methods were tested, and a comparison between their use and the ergonomic analysis...

  13. The Interaction between Personality, Social Network Position and Involvement in Innovation Process

    NARCIS (Netherlands)

    E. Dolgova; W. van Olffen (Woody); F.A.J. van den Bosch (Frans); H.W. Volberda (Henk)

    2010-01-01

    textabstractAbstract This dissertation proposal investigates how personality and individuals’ social network position affect individuals’ involvement into the innovation process. It posits that people would feel inclined to become involved into the different phases of the innovation process dependin

  14. Across frequency processes involved in auditory detection of coloration

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Kerketsos, P

    2008-01-01

    When an early wall reflection is added to a direct sound, a spectral modulation is introduced to the signal's power spectrum. This spectral modulation typically produces an auditory sensation of coloration or pitch. Throughout this study, auditory spectral-integration effects involved in coloration...... detection are investigated. Coloration detection thresholds were therefore measured as a function of reflection delay and stimulus bandwidth. In order to investigate the involved auditory mechanisms, an auditory model was employed that was conceptually similar to the peripheral weighting model [Yost, JASA......, 1982, 416-425]. When a “classical” gammatone filterbank was applied within this spectrum-based model, the model largely underestimated human performance at high signal frequencies. However, this limitation could be resolved by employing an auditory filterbank with narrower filters. This novel...

  15. Research Education: Perspectives and subjective processes involved in educational research

    Directory of Open Access Journals (Sweden)

    Harm H. Tillema

    2009-10-01

    Full Text Available Educational research acknowledges that researcher’s beliefs and training play a role in framing the outcomes of any study. Research not only consists of defining objectives and following certain methods (search but also of making decisions over the steps taking during the inquiry process (research.Establishing a conceptual framework to guide actions on the subjective processes in research is then crucial to control them. With that purpose in mind we offer researchers and Teacher Educators a heuristic tool to be conscious on the risks that can be taken when immersed in research interpretative process. This instrument could be utilised in PhD programs, masters and research projects.

  16. Enhanced electrocatalytic performance of processed, ultrathin, supported Pd-Pt core-shell nanowire catalysts for the oxygen reduction reaction.

    Science.gov (United States)

    Koenigsmann, Christopher; Santulli, Alexander C; Gong, Kuanping; Vukmirovic, Miomir B; Zhou, Wei-ping; Sutter, Eli; Wong, Stanislaus S; Adzic, Radoslav R

    2011-06-29

    We report on the synthesis, characterization, and electrochemical performance of novel, ultrathin Pt monolayer shell-Pd nanowire core catalysts. Initially, ultrathin Pd nanowires with diameters of 2.0 ± 0.5 nm were generated, and a method has been developed to achieve highly uniform distributions of these catalysts onto the Vulcan XC-72 carbon support. As-prepared wires are activated by the use of two distinctive treatment protocols followed by selective CO adsorption in order to selectively remove undesirable organic residues. Subsequently, the desired nanowire core-Pt monolayer shell motif was reliably achieved by Cu underpotential deposition followed by galvanic displacement of the Cu adatoms. The surface area and mass activity of the acid and ozone-treated nanowires were assessed, and the ozone-treated nanowires were found to maintain outstanding area and mass specific activities of 0.77 mA/cm(2) and 1.83 A/mg(Pt), respectively, which were significantly enhanced as compared with conventional commercial Pt nanoparticles, core-shell nanoparticles, and acid-treated nanowires. The ozone-treated nanowires also maintained excellent electrochemical durability under accelerated half-cell testing, and it was found that the area-specific activity increased by ~1.5 fold after a simulated catalyst lifetime.

  17. Analisis Kinerja Supplier Bahan Baku Menggunakan Integrasi Supply Chain Operations Refrence dan Analytic Hierarchy Process PT. Asia Raya Foundry

    OpenAIRE

    Jati, Wahyu Listyo

    2015-01-01

    Persaingan bisnis yang semakin cepat menuntut PT. Asia Raya Foundry sebagai salah satu perusahaan yang bergerak dibidang manufaktur pengecoran logam untuk produksi spare part mesin pabrik perkebunan dan alat berat harus memperhatikan keinginan konsumen terhadap produk. Berdasarkan penelitian yang dilakukan terdapat keluhan dari pabrik terhadap pasokan bahan baku langsung yang diperoleh dari supplier sehingga menyebabkan adanya keterlambatan dalam penyelesaian produk. Gangguan yang disebabkan ...

  18. Highly (1 1 1)-oriented and pyrochlore-free PMN-PT thin films derived from a modified sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Feng, M. [Institute for Advanced Ceramics, Department of Materials Science and Engineering, Harbin Institute of Technology, No. 92, West Da-Zhi Street, Heilongjiang, Harbin 150001 (China); Wang, W., E-mail: wangwen@hit.edu.c [Institute for Advanced Ceramics, Department of Materials Science and Engineering, Harbin Institute of Technology, No. 92, West Da-Zhi Street, Heilongjiang, Harbin 150001 (China); Ke, H.; Rao, J.C.; Zhou, Y. [Institute for Advanced Ceramics, Department of Materials Science and Engineering, Harbin Institute of Technology, No. 92, West Da-Zhi Street, Heilongjiang, Harbin 150001 (China)

    2010-04-09

    Ferroelectric PMN-PT (68/32) thin films, about 250 nm in thickness, have been successfully grown on Pt/Ti/SiO{sub 2}/Si substrate by a modified sol-gel process. Pure perovskite phase with highly (1 1 1)-preferred orientation, determined by X-ray diffraction, was formed in the PMN-PT thin films when annealed at 650 {sup o}C. The pyrochlore phase has been effectively avoided through a variation of the processing parameters such as Mg content, Mg precursor and annealing temperature during thin film deposition. FE-SEM investigation showed that the films have a smooth and crack-free surface with densely packed grains after annealed at 650 {sup o}C. The annealed films exhibited well-defined hysteresis loops, with a respective remanent polarization P{sub r} of 16.1 {mu}C/cm{sup 2} and coercive field E{sub c} of 71.2 kV/cm at an applied electric field of 400 kV/cm at room temperature.

  19. Improving industrial designers work process by involving user research

    DEFF Research Database (Denmark)

    Dai, Zheng; Ómarsson, Ólafur

    2011-01-01

    With changing times, new technologies and more opinionated consumers, the modern industrial designer has found himself in need of fresher and more up to date approaches in his daily work. In a fast moving industry, the designer needs to keep a thinking process of dynamic and subjective attitude...

  20. Improving industrial designers work process by involving user research

    DEFF Research Database (Denmark)

    Dai, Zheng; Ómarsson, Ólafur

    2011-01-01

    With changing times, new technologies and more opinionated consumers, the modern industrial designer has found himself in need of fresher and more up to date approaches in his daily work. In a fast moving industry, the designer needs to keep a thinking process of dynamic and subjective attitude....... User research is part of user centered design (UCD). UCD has a reputation for subjective and reflective practice. In this paper there are two example cases. One is conducted by a classical industrial design process, and another is costing half of energy and time in user research. These examples...... will give the grounding for believing that the industrial designer needs to adopt user research methods to a level where he can still continue to work under the very nature of industrial design that has made it a successful practice for the last century. The combing of the approaches and attitude will help...

  1. Issues involved in the process of developing a medical food.

    Science.gov (United States)

    Ochoa, Juan B; McClave, Stephen A; Saavedra, Jose

    2011-09-01

    The creation of a medical food with potential health benefits for a particular patient population is a surprisingly complex process. Fortunately, the developmental process for a specific medical food is not as rigorous or as tightly regulated as that of a pharmaceutical agent. However, numerous factors unique to the enteral formulation of a new product come into play, such as physical/chemical compatibility, pH, stability, bioavailability, decay, and even palatability. Additional considerations such as strength of health benefit claims, packaging or presentation, and marketability determine the ultimate commercialization and whether a product ends up being released to the public. A full understanding of the development, substantiation, and commercialization of a medical food is necessary for important physiologic concepts in nutrition therapy to end up as part of the therapeutic regimen at the bedside of the critically ill obese patient.

  2. Kinetic processes in solid helium involving impurities and vacancies (Review)

    Science.gov (United States)

    Maidanov, V. A.; Rudavskii, E. Ya.; Sokolov, S. S.

    2017-01-01

    A brief review is given of the kinetic behavior of impurities and vacancies in solid helium, which Andreev and Lifshitz predicted should be delocalized and converted into unique quasiparticles. Primary attention is devoted to the unusual diffusion processes in solid 3He-4He solutions as they undergo phase separation. Because mechanical stresses develop in the crystal during separation, the diffusive flow is substantially reduced and the effective diffusion coefficient becomes smaller than the coherent quantum diffusion coefficient. During the inverse transition from a separated mixture into the homogeneous state, anomalously rapid mass transfer is observed which can be explained qualitatively in terms of a model in which 3He inclusions are dissolved in three stages. Experimental data on the kinetics of phase separation are compared with a diffusive description of the process that takes into account the difference between diffusion processes outside and inside a nucleus of the new phase. Good agreement is obtained between a theoretical calculation and the experimental data. A homogeneous nucleation model is used to estimate the concentration of nuclei. For the first time, the coefficient of mass diffusion is estimated over the entire range of the concentration of the solutions. The behavior of delocalized vacancies in 4He and 3He solid solutions is studied near the separation temperature. The observed features of the pressure in this kind of system during repeated temperature cycling are explained by the formation of pure 4He vacancy clusters. Although the crystal itself has no strict periodicity owing to the random separation of 3He and 4He atoms at the lattice sites, a periodic structure is realized within a cluster and vacancies become delocalized.

  3. Anionic Pt in Silicate Melts at Low Oxygen Fugacity: Speciation, Partitioning and Implications for Core Formation Processes on Asteroids

    Science.gov (United States)

    Medard, E.; Martin, A. M.; Righter, K.; Malouta, A.; Lee, C.-T.

    2017-01-01

    Most siderophile element concentrations in planetary mantles can be explained by metal/ silicate equilibration at high temperature and pressure during core formation. Highly siderophile elements (HSE = Au, Re, and the Pt-group elements), however, usually have higher mantle abundances than predicted by partitioning models, suggesting that their concentrations have been set by late accretion of material that did not equilibrate with the core. The partitioning of HSE at the low oxygen fugacities relevant for core formation is however poorly constrained due to the lack of sufficient experimental constraints to describe the variations of partitioning with key variables like temperature, pressure, and oxygen fugacity. To better understand the relative roles of metal/silicate partitioning and late accretion, we performed a self-consistent set of experiments that parameterizes the influence of oxygen fugacity, temperature and melt composition on the partitioning of Pt, one of the HSE, between metal and silicate melts. The major outcome of this project is the fact that Pt dissolves in an anionic form in silicate melts, causing a dependence of partitioning on oxygen fugacity opposite to that reported in previous studies.

  4. Fabrication of Supported AuPt Alloy Nanocrystals with Enhanced Electrocatalytic Activity for Formic Acid Oxidation through Conversion Chemistry of Layer-Deposited Pt(2+) on Au Nanocrystals.

    Science.gov (United States)

    Kim, Seong Hyeon; Jeong, Hwakyeung; Kim, Jongwon; Lee, In Su

    2015-10-07

    The exploitation of nanoconfined conversion of Au- and Pt-containing binary nanocrystals for developing a controllable synthesis of surfactant-free AuPt nanocrystals with enhanced formic acid oxidation (FAO) activity is reported, which can be stably and evenly immobilized on various support materials to diversify and optimize their electrocatalytic performance. In this study, an atomic layer of Pt(2+) species is discovered to be spontaneously deposited in situ on the Au nanocrystal generated from a reverse-microemulsion solution. The resulting Au/Pt(2+) nanocrystal thermally transforms into a reduced AuPt alloy nanocrystal during the subsequent solid-state conversion process within the SiO2 nanosphere. The alloy nanocrystals can be isolated from SiO2 in a surfactant-free form and then dispersedly loaded on the carbon sphere surface, allowing for the production of a supported electrocatalyst that exhibits much higher FAO activity than commercial Pt/C catalysts. Furthermore, by involving Fe3O4 nanocrystals in the conversion process, the AuPt alloy nanocrystals can be grown on the oxide surface, improving the durability of supported metal catalysts, and then uniformly loaded on a reduced graphene oxide (RGO) layer with high electroconductivity. This produces electrocatalytic AuPt/Fe3O4/RGO nanocomposites whose catalyst-oxide-graphene triple-junction structure provides improved electrocatalytic properties in terms of both activity and durability in catalyzing FAO. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. [The decision to abort: the process and feelings involved].

    Science.gov (United States)

    Costa, R G; Hardy, E; Osis, M J; Faúndes, A

    1995-01-01

    In Brazil, induced abortion is considered a crime in the majority of cases, the result being that there is little official data on the subject. Little is known about the conditions under which abortions are induced This research was designed to shed light on the characteristics of the women who had had an abortion and to study the reasons why and conditions under which it occurred. The sample consisted of all employees (7,359) and students (2,231) in a university program in S o Paulo who were mailed a self-administered survey. Accompanying the questionnaire was a letter and self-addressed stamped envelope. 27% of the employees and 42% of the students returned the questionnaires. Of these, 1,314 employees and 138 students had had at least one pregnancy. The results presented in this study show that 465 of the employees and students ar some point had thought of having an abortion. They were divided into two groups: those who had had an abortion and those who had nos. The objective was to analyze the association of some characteristics of the women with their decision to have/not have an abortion and how they felt when faced with this decision. The proportion of women who had had an abortion was significantly lower among married women than singles. A larger percentage of women who had talked with a friend and/or husband/partner/boyfriend had decided to have an abortion than those who had talked to a parent or had not talked to anyone. More women who said they were not prepared to raise/educate a child had had an abortion as compared to those giving other reasons. Almost half of the women undergoing an abortion said that they felt bad emotionally and physically afterwards. Among those who had not had an abortion, almost two-fifths reported that they felt good, were happy, relieved, and did not regret their decision. The conclusion drawn from the population studied was that emotional and social factors played a significant role in the decision-making process for women

  6. High Activity of Hexagonal Ag/Pt Nanoshell Catalyst for Oxygen Electroreduction

    Directory of Open Access Journals (Sweden)

    Lee Chien-Liang

    2008-01-01

    Full Text Available Abstract Hexagonal Ag/Pt nanoshells were prepared by using a hexagonal Ag nanoplate as the displacement template and by introducing Pt ions. The prepared Ag/Pt nanoshells played the role of an electrocatalyst in an oxygen reduction process. Compared to spherical Pt and Ag/Pt nanoparticles, the hexagonal Ag/Pt nanoshells showed higher activity for oxygen electroreduction.

  7. Synthesis of sub-nanosized Pt particles on mesoporous SBA-15 material and its application to the CO oxidation reaction

    Science.gov (United States)

    Wu, Hung-Chi; Chen, Tse-Ching; Lai, Nien-Chu; Yang, Chia-Min; Wu, Jia-Huang; Chen, Yan-Chu; Lee, Jyh-Fu; Chen, Ching-Shiun

    2015-10-01

    In this work, we show that the size and shape of Pt nanoparticles in SBA-15 can be controlled through vacuum and air calcination. The vacuum-calcination/H2-reduction process is used to thermally treat a 0.2 wt% Pt4+/SBA-15 sample to obtain small 2D clusters and single atoms that can significantly increase Pt dispersion in SBA-15. Compared with thermal treatments involving air-calcination/H2-reduction, which result in ~4.6 nm rod-like Pt particles, vacuum-calcination/H2-reduction can dramatically reduce the size of the Pt species to approximately 0.5-0.8 nm. The Pt particles undergoing air-calcination/H2-reduction have poor conversion efficiency because the fraction of terrace sites, the major sites for CO oxidation, on the rod-like Pt particles is small. In contrast, a large amount of low-coordinated Pt sites associated with 2D Pt species and single Pt atoms in SBA-15 is effectively generated through the vacuum-calcination/H2-reduction process, which may facilitate CO adsorption and induce strong reactivity toward CO oxidation. We investigated the effect of vacuum-calcination/H2-reduction on the formation of tiny 2D clusters and single atoms by characterizing the particles, elucidating the mechanism of formation, determining the active sites for CO oxidation and measuring the heat of CO adsorption.

  8. Surface Segregation in Supported Pd-Pt Nanoclusters and Alloys

    NARCIS (Netherlands)

    van den Oetelaar, L.C.A.; Nooij, O.W.; Oerlemans, S.; Denier van der Gon, A.W.; Brongersma, H.H.; Lefferts, Leonardus; Roosenbrand, A.G.; van Veen, J.A.R.

    1998-01-01

    Surface segregation processes in Pd-Pt alloys and bimetallic Pd-Pt nanoclusters on alumina and carbon supports (technical catalysts) have been investigated by determining the metal surface composition of these systems by low-energy ion scattering (LEIS). Both Pd-rich (Pd80Pt20) and Pt-rich

  9. Nanocrystalline Fe-Pt alloys. Phase transformations, structure and magnetism

    Energy Technology Data Exchange (ETDEWEB)

    Lyubina, J.V.

    2006-12-21

    This work has been devoted to the study of phase transformations involving chemical ordering and magnetic properties evolution in bulk Fe-Pt alloys composed of nanometersized grains. Nanocrystalline Fe{sub 100-x}Pt{sub x} (x=40-60) alloys have been prepared by mechanical ball milling of elemental Fe and Pt powders at liquid nitrogen temperature. The as-milled Fe-Pt alloys consist of {proportional_to} 100 {mu}m sized particles constituted by randomly oriented grains having an average size in the range of 10-40 nm. Depending on the milling time, three major microstructure types have been obtained: samples with a multilayer-type structure of Fe and Pt with a thickness of 20-300 nm and a very thin (several nanometers) A1 layer at their interfaces (2 h milled), an intermediate structure, consisting of finer lamellae of Fe and Pt (below approximately 100 nm) with the A1 layer thickness reaching several tens of nanometers (4 h milled) and alloys containing a homogeneous A1 phase (7 h milled). Subsequent heat treatment at elevated temperatures is required for the formation of the L1{sub 0} FePt phase. The ordering develops via so-called combined solid state reactions. It is accompanied by grain growth and thermally assisted removal of defects introduced by milling and proceeds rapidly at moderate temperatures by nucleation and growth of the ordered phases with a high degree of the long-range order. In a two-particle interaction model elaborated in the present work, the existence of hysteresis in recoil loops has been shown to arise from insufficient coupling between the low- and the high-anisotropy particles. The model reveals the main features of magnetisation reversal processes observed experimentally in exchange-coupled systems. Neutron diffraction has been used for the investigation of the magnetic structure of ordered and partially ordered nanocrystalline Fe-Pt alloys. (orig.)

  10. Modeling and Compensatory Processes Underlying Involvement in Child Care among Kibbutz-Reared Fathers

    Science.gov (United States)

    Gaunt, Ruth; Bassi, Liat

    2012-01-01

    This study examined modeling and compensatory processes underlying the effects of an early paternal model on father involvement in child care. Drawing on social learning theory, it was hypothesized that father-son relationships would moderate the association between a father's involvement and his own father's involvement. A sample of 136 kibbutz…

  11. Eucalyptus grandis Hill ex Maiden inoculated with Pisolithus microcarpus (UFSC-Pt116) in land subject to the sandy process in Southern Brazil.

    Science.gov (United States)

    de Souza, Eduardo Lorensi; Antoniolli, Zaida Inês; Machado, Rafael Goulart; Eckhardt, Daniel Pazzini; Dahmer, Sabrina de Fátima Barbosa

    2014-01-01

    Eucalypts is one of the main species used for commercial reforestation in the Rio Grande do Sul State, Brazil. This study aimed to evaluate the survival and early growth of eucalyptus trees in an area subject to sandy process after three years of growth. The Eucalyptus grandis seedlings were grown in a greenhouse, inoculated or not with the isolated ectomycorrhizal Pisolithus microcarpus (UFSC-Pt116), produced in peat or Entisol. After 120 days, the seedlings were transplanted to an area subject to the sandy process, in the São Francisco de Assis city, RS. The plants have been evaluated regarding survival, height, stem diameter, nitrogen, phosphorus and potassium levels and total phosphorus, inorganic phosphorus, organic phosphorus and wood production on different days after planting. The seedlings grown on the Entisol which was inoculated with the isolated UFSC-Pt116 presented higher survival rates, height, stem diameter, nitrogen concentration and wood production then non-inoculated seedlings. Inoculation with ectomycorrhizal fungi enhanced the production of E. grandis seedlings in survival rates, height, stem diameter.

  12. Superior long-term activity for a Pt-Re alloy compared to Pt in methanol oxidation reactions

    Science.gov (United States)

    Duke, Audrey S.; Xie, Kangmin; Monnier, John R.; Chen, Donna A.

    2017-03-01

    Pt-Re bimetallic catalysts have shown enhanced activity compared to pure Pt for reactions involving oxidation, but the origins of this improved activity are not fully understood. Methanol oxidation on a Pt-Re alloy surface and pure Pt foil was studied in a microreactor coupled to an ultrahigh vacuum chamber. For reaction at 60 °C, the Pt-Re alloy surface exhibits superior long-term activity over a 24 h reaction period compared to pure Pt. The initial activity of Pt is 10-15% higher than on Pt-Re; however, the Pt surface gradually loses activity after 10 h online, whereas the activity of Pt-Re does not diminish. Post-reaction XPS shows that more carbon accumulates on the Pt than on Pt-Re, and the improved long-term activity is attributed to a greater ability of Pt-Re to oxidize the carbonaceous intermediates that eventually poison active sites. Both Pt and Pt-Re surfaces have almost no activity for methanol oxidation until a minimum coverage of oxygen is achieved from O2 dissociation. A comparison with methanol oxidation studies on Pt and Pt-Re in a pressure regime that is 150 times lower than in this work demonstrates that more carbon and less oxygen accumulate on the surfaces during reaction at the lower pressures.

  13. Ore mineralogy of the Serra Pelada Au-Pd-Pt deposit, Carajás, Brazil and implications for ore-forming processes

    Science.gov (United States)

    Berni, Gabriel V.; Heinrich, Christoph A.; Lobato, Lydia M.; Wall, Vic

    2016-08-01

    Serra Pelada is a world-class hydrothermal Au-Pd-Pt deposit located at the eastern border of the Amazon craton, northern Brazil. The rocks at Serra Pelada have experienced intense tropical weathering for about 70 Ma, but drill core samples preserve the primary mineralogy and hydrothermal alteration features, with extreme grades of Au, Pd and Pt individually reaching hundreds of parts per million (ppm) by weight. Mineralization at Serra Pelada occurs in hydrothermally altered metasiltstones and dolomitic metasandstones at the hinge zone of a recumbent syncline, comprising zones of hematite, chlorite-carbon, argillic, and siliceous alteration. The main hydrothermal gangue minerals are quartz, kaolinite, sericite, amesite, hematite, monazite, florencite and variable amounts of highly reflective carbonaceous matter. Hydrothermal carbon input is evident from precipitated carbon occurring along crenulation planes and veinlets associated with the precious metals. Ore and accessory minerals include a variety of sulphide, selenide, arsenide, sulphate and oxide minerals, including gold with variable metal contents, palladian gold, fischesserite, sudovikovite, sperrylite, selenian braggite, isomertieite, mertieite-II and secondary Au-Pt-Pd alloys. The composition of fischesserite varies from the ideal formula (Ag3AuSe2) towards a more Ag-rich composition, indicating a disordered solid solution form that is stable only above 260 °C, consistent with the high thermal maturity of associated carbonaceous matter approaching graphite. Primary ore and gangue minerals at Serra Pelada comprise a suite of elements that are best transported in oxidising conditions and precipitated upon reduction. This suggests that fluid mixing between a highly oxidised (metal carrier) and a reduced fluid was a key process for high-grade noble metal precipitation at Serra Pelada.

  14. Surface-Limited Synthesis of Pt Nanocluster Decorated Pd Hierarchical Structures with Enhanced Electrocatalytic Activity toward Oxygen Reduction Reaction.

    Science.gov (United States)

    Yang, Tao; Cao, Guojian; Huang, Qingli; Ma, Yanxia; Wan, Sheng; Zhao, Hong; Li, Na; Sun, Xia; Yin, Fujun

    2015-08-12

    Exploring superior catalysts with high catalytic activity and durability is of significant for the development of an electrochemical device involving the oxygen reduction reaction. This work describes the synthesis of Pt-on-Pd bimetallic heterogeneous nanostructures, and their high electrocatalytic activity toward the oxygen reduction reaction (ORR). Pt nanoclusters with a size of 1-2 nm were generated on Pd nanorods (NRs) through a modified Cu underpotential deposition (UPD) process free of potential control and a subsequent surface-limited redox reaction. The Pt nanocluster decorated Pd nanostructure with a ultralow Pt content of 1.5 wt % exhibited a mass activity of 105.3 mA mg(-1) (Pt-Pd) toward ORR, comparable to that of the commercial Pt/C catalyst but 4 times higher than that of carbon supported Pd NRs. More importantly, the carbon supported Pt-on-Pd catalyst displays relatively small losses of 16% in electrochemical surface area (ECSA) and 32% in mass activity after 10 000 potential sweeps, in contrast to respective losses of 46 and 64% for the commercial Pt/C catalyst counterpart. The results demonstrated that Pt decoration might be an efficient way to improve the electrocatalytic activity of Pd and in turn allow Pd to be a promising substitution for commercial Pt catalyst.

  15. Identification of {sup 166}Pt and {sup 167}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, C.R.; Toth, K.S.; Batchelder, J.C.; Blumenthal, D.J.; Brown, L.T.; Busse, B.C.; Conticchio, L.F.; Davids, C.N.; Davinson, T.; Henderson, D.J.; Irvine, R.J.; Seweryniak, D.; Walters, W.B.; Woods, P.J.; Zimmerman, B.E. [The University of Tennessee, Knoxville, Tennessee 37996 (United States)]|[Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)]|[Louisiana State University, Baton Rouge, Louisiana 70803 (United States)]|[Argonne National Laboratory, Argonne, Illinois 60439 (United States)]|[Vanderbilt University, Nashville, Tennessee 37235 (United States)]|[Oregon State University, Corvallis, Oregon 97331 (United States)]|[University of Maryland, College Park, Maryland 20742 (United States)]|[Edinburgh University, Edinburgh, EH9 3JZ (United Kingdom)

    1996-07-01

    In a series of {sup 78}Kr bombardments of {sup 92}Mo the new isotopes {sup 166}Pt and {sup 167}Pt were identified via their {alpha}-decay properties. The {alpha}-decay energies and half-lives of these two nuclides are as follows. (1) {sup 166}Pt, {ital E}{sub {alpha}} = 7110(15) keV, {ital T}{sub 1/2} = 0.3(1) ms, and (2) {sup 167}Pt, {ital E}{sub {alpha}} = 6988(10) keV, {ital T}{sub 1/2} = 0.7(2) ms. Also, the half-life of {sup 168}Pt, which was previously unknown, was determined to be 2.0(4) ms. In a separate but concurrent experiment involving {sup 78}Kr + {sup 96}Ru reactions, {sup 170}Pt was made and a half-life of 14.7(5) ms was measured for it; the one published value is 6{sub {minus}2}{sup +5} ms. Results for {sup 162{minus}164}Os contained in the same data sets were also analyzed and by using mother-daughter correlations, the {alpha} branches of {sup 162,163,164}Os were established to be near 100{percent}. {copyright} {ital 1996 The American Physical Society.}

  16. An Exploration of Team Information Processing in a Dynamic Group Choice Task Involving Uncertainty

    Science.gov (United States)

    1988-01-01

    School of Systems and Logistics , and to Lt (ohonol John Dumond, Head of the Departmvnt of System 1,cquimition Miigaemont, who encouraged me and...2PT 2PL-4PT 3PL -5PT XCERT SCOPE SWAT Team I Fast Seo, 1 0.040 0.000 0.830 1.000 0,082 03.8 5•8.2 2 0,000 0.000 0.070 0.880 0,589 01.7 54,8 3 0,040 0.040...TABLE !.10, Continued Alphabetic presentation form, without heuristios IPL-IPT 2PL-2PT 2PL𔃾PT 3PL -5PT %CERT SCORK SWAT Tesm 5 Fast Soem 1 0.000 0.000

  17. Pt promotion and spill-over processes during deposition and desorption of upd-H(ad) and OH(ad) on Pt(x)Ru(1-x)/Ru(0001) surface alloys.

    Science.gov (United States)

    Hoster, Harry E; Janik, Michael J; Neurock, Matthew; Behm, R Jürgen

    2010-09-21

    The electrochemical adsorption of underpotential deposited hydrogen (upd-H(ad)) and OH(ad) on structurally well-defined Pt(x)Ru(1-x)/Ru(0001) surface alloys was investigated by cyclic voltammetry and density functional theory (DFT) calculations. The adsorption energies of both upd-H(ad) and OH(ad) decrease with increasing Pt content in the adsorption ensemble, shifting the onset of upd-H(ad) and OH(ad) formation to increasingly cathodic and anodic potentials, respectively. For bare Ru(0001) and for Ru(3) sites in the surface alloy, the stability regions of these two species overlap or almost overlap, respectively. Similar to previous findings for upd-H(ad) adsorption/desorption on partly Pt monolayer island covered Ru(0001) surfaces (J. Phys. Chem. B 2004, 108, 14780), we find a sharp peak at approximately 100 mV vs. RHE in each scan direction, which is attributed to a Pt catalyzed OH(ad) upd-H(ad) replacement on Ru(3) sites, via adsorption on Pt rich sites and spill-over to Ru(3) sites. The decrease of the integrated charge in these peaks with the third power of the Ru surface concentration, which for a random distribution of surface atoms reflects the availability of Ru(3) sites, supports the above assignment.

  18. Modeling of PEM fuel cell Pt/C catalyst degradation

    Science.gov (United States)

    Bi, Wu; Fuller, Thomas F.

    Pt/C catalyst degradation remains as one of the primary limitations for practical applications of proton exchange membrane (PEM) fuel cells. Pt catalyst degradation mechanisms with the typically observed Pt nanoparticle growth behaviors have not been completely understood and predicted. In this work, a physics-based Pt/C catalyst degradation model is proposed with a simplified bi-modal particle size distribution. The following catalyst degradation processes were considered: (1) dissolution of Pt and subsequent electrochemical deposition on Pt nanoparticles in cathode; (2) diffusion of Pt ions in the membrane electrode assembly (MEA); and (3) Pt ion chemical reduction in membrane by hydrogen permeating through the membrane from the negative electrode. Catalyst coarsening with Pt nanoparticle growth was clearly demonstrated by Pt mass exchange between small and large particles through Pt dissolution and Pt ion deposition. However, the model is not adequate to predict well the catalyst degradation rates including Pt nanoparticle growth, catalyst surface area loss and cathode Pt mass loss. Additional catalyst degradation processes such as new Pt cluster formation on carbon support and neighboring Pt clusters coarsening was proposed for further simulative investigation.

  19. Reading for Repetition and Reading for Translation: Do They Involve the Same Processes?

    Science.gov (United States)

    Macizo, Pedro; Bajo, M. Teresa

    2006-01-01

    Theories of translation differ in the role assigned to the reformulation process. One view, the ''horizontal'' approach, considers that translation involves on-line searches for matches between linguistic entries in the two languages involved [Gerver, D. (1976). Empirical studies of simultaneous interpretation: A review and a model. In R. W.…

  20. The Nature of Parental Involvement in the Schooling Process in Katsina State

    Science.gov (United States)

    Ibrahim, Ahmed Tijjani; Jamil, Hazri Bin

    2012-01-01

    Parental involvement in the schooling process of their children seems to be a neglected research area especially in primary schools of Katsina state in Nigeria. Parental involvement as envisaged by Donald, Lazarus and Lolwana (2006) for purposes of transformation cannot be overemphasized by both parents and teachers in schools. Therefore, parents…

  1. Pt skin coated hollow Ag-Pt bimetallic nanoparticles with high catalytic activity for oxygen reduction reaction

    Science.gov (United States)

    Fu, Tao; Huang, Jianxing; Lai, Shaobo; Zhang, Size; Fang, Jun; Zhao, Jinbao

    2017-10-01

    The catalytic activity and stability of electrocatalyst is critical for the commercialization of fuel cells, and recent reports reveal the great potential of the hollow structures with Pt skin coat for developing high-powered electrocatalysts due to their highly efficient utilization of the Pt atoms. Here, we provide a novel strategy to prepare the Pt skin coated hollow Ag-Pt structure (Ag-Pt@Pt) of ∼8 nm size at room temperature. As loaded on the graphene, the Ag-Pt@Pt exhibits a remarkable mass activity of 0.864 A/mgPt (at 0.9 V, vs. reversible hydrogen electrode (RHE)) towards oxygen reduction reaction (ORR), which is 5.30 times of the commercial Pt/C catalyst, and the Ag-Pt@Pt also shows a better stability during the ORR catalytic process. The mechanism of this significant enhancement can be attributed to the higher Pt utilization and the unique Pt on Ag-Pt surface structure, which is confirmed by the density functional theory (DFT) calculations and other characterization methods. In conclusion, this original work offers a low-cost and environment-friendly method to prepare a high active electrocatalyst with cheaper price, and this work also discloses the correlation between surface structures and ORR catalytic activity for the hollow structures with Pt skin coat, which can be instructive for designing novel advanced electrocatalysts for fuel cells.

  2. The approaches to the definition of involvement and to types of companies-customers involvement in decision-making process

    Directory of Open Access Journals (Sweden)

    M.Yu. Troian

    2011-10-01

    Full Text Available The approaches to the definition of involvement and toits basic types classification are developed. The classification of types of companies-customers involvement is supplemented. The concept of connotative involvement is defined and scientifically proven. The basic properties of the involvement: the intensity, directionandstability are developed.

  3. Pt-Pd nanoelectrocatalyst of ultralow Pt content for the oxidation of formic acid: Towards tuning the reaction pathway

    Indian Academy of Sciences (India)

    Sourov Ghosh; C Retna Raj

    2015-05-01

    Synthesis of highly efficient functional electrocatalyst that favours the electrochemical oxidation of formic acid via CO-free dehydrogenation pathway is required for direct formic acid fuel cells. Traditional catalysts favour the dehydration pathway involving the generation of poisonous CO. Herein we demonstrate the superior electrocatalytic performance of Pt-Pd bimetallic nanoelectrocatalyst of ultralow Pt content and tuning the reaction pathway by controlling the Pt content. Bimetallic nanoparticles of Pt4Pd96, Pt7Pd93 and Pt47Pd53 compositions are synthesized by electrochemical co-deposition method in aqueous solution. The nanoparticles of ultralow Pt content, Pt4Pd96, favour the CO-free dehydrogenation pathway for formic acid oxidation with an onset potential of 0 V (SHE) whereas the Pt47Pd53 nanoparticles favour the dehydration pathway involving the formation of CO at high positive potential. The Pt content of the bimetallic nanoparticles actually controls the oxidation peak potential and catalytic activity. Significant negative shift (∼350 mV) in the oxidation peak potential and remarkable enhancement in the current density (2.6 times) are observed for Pt4Pd96 nanoparticles with respect to Pt47Pd53. The absence of three adjacent Pt and Pd atoms could be the reason for the suppression of CO pathway. The electrochemical impedance measurements indirectly support the CO-free pathway for the formic acid oxidation on Pt4Pd96 nanoparticles.

  4. Determining Carbon and Oxygen Stable Isotope Systematics in Brines at Elevated p/T Conditions to Enhance Monitoring of CO2 Induced Processes in Carbon Storage Reservoirs

    Science.gov (United States)

    Becker, V.; Myrttinen, A.; Mayer, B.; Barth, J. A.

    2012-12-01

    Stable carbon isotope ratios (δ13C) are a powerful tool for inferring carbon sources and mixing ratios of injected and baseline CO2 in storage reservoirs. Furthermore, CO2 releasing and consuming processes can be deduced if the isotopic compositions of end-members are known. At low CO2 pressures (pCO2), oxygen isotope ratios (δ18O) of CO2 usually assume the δ18O of the water plus a temperature-dependent isotope fractionation factor. However, at very high CO2 pressures as they occur in CO2 storage reservoirs, the δ18O of the injected CO2 may in fact change the δ18O of the reservoir brine. Hence, changing δ18O of brine constitutes an additional tracer for reservoir-internal carbon dynamics and allows the determination of the amount of free phase CO2 present in the reservoir (Johnson et al. 2011). Further systematic research to quantify carbon and oxygen isotope fractionation between the involved inorganic carbon species (CO2, H2CO3, HCO3-, CO32-, carbonate minerals) and kinetic and equilibrium isotope effects during gas-water-rock interactions is necessary because p/T conditions and salinities in CO2 storage reservoirs may exceed the boundary conditions of typical environmental isotope applications, thereby limiting the accuracy of stable isotope monitoring approaches in deep saline formations (Becker et al. 2011). In doing so, it is crucial to compare isotopic patterns observed in laboratory experiments with artificial brines to similar experiments with original fluids from representative field sites to account for reactions of dissolved inorganic carbon (DIC) with minor brine components. In the CO2ISO-LABEL project, funded by the German Ministry for Education and Research, multiple series of laboratory experiments are conducted to determine the influence of pressure, temperature and brine composition on the δ13C of DIC and the δ18O of brines in water-CO2-rock reactions with special focus placed on kinetics and stable oxygen and carbon isotope fractionation

  5. Prothrombin time (PT)

    Science.gov (United States)

    PT; Pro-time; Anticoagulant-prothrombin time; Clotting time: protime; INR; International normalized ratio ... PT is measured in seconds. Most of the time, results are given as what is called INR ( ...

  6. The Longitudinal Process of Early Parent Involvement on Student Achievement: A Path Analysis.

    Science.gov (United States)

    Hayakawa, Momoko; Englund, Michelle M; Warner-Richter, Mallory N; Reynolds, Arthur J

    2013-01-01

    This longitudinal study investigated the process whereby early parent involvement in preschool effects student achievement from kindergarten through 6(th) grade. Participants were 1,539 low-income, mainly African American children and their mothers, in the Chicago Longitudinal Study. Program children (N = 989) received one or two years of the Child-Parent Center (CPC) program - a preschool intervention that strongly promoted parents' development of parent involvement skills within the school and at home. Children from similar backgrounds who did not attend the CPC, but participated in available local resources (e.g. day care), were obtained as a comparison group (N = 550). Path analysis revealed an interactive process between parent involvement, academic achievement, and children's motivation. Early parent involvement directly influenced kindergarten achievement, which in turn influenced first grade student motivation. Highly motivated children then encouraged parents to continue involvement. The cyclic nature of this process across elementary school was observed. The model accounted for 61% of the variance in 6(th) grade achievement. Findings suggest that early parent involvement promoted in the CPC program, sets the stage for subsequent parent involvement, student motivation, and academic achievement throughout early and middle childhood.

  7. Lean Strategy Implementation to Improve Throughput in Assembly Line: Dul-Db21ssc Manufacturing Process at PT. X

    Directory of Open Access Journals (Sweden)

    Gemma Eka Santoso

    2013-06-01

    Full Text Available Lean production has dramatically lifted the competitiveness of many manufacturing companies and the value they deliver to customers. This project examines the benefit of balancing process and workstation arrangement of dogbone damper in an order that maintains a smooth flow of materials and component through the process. The analysis begins from calculating takt value to establish the required rate of production. From here, any total cycle time exceeding takt time is called a bottleneck process and should become a target of the improvement. Next, arranging people and equipment into cells has great advantage in terms of achieving lean goals. One advantage of cells is the one-piece flow concept, which states that each product moves through the process one unit a time without sudden interruption, at a pace determined by the customer’s need.  

  8. Lean Strategy Implementation to Improve Throughput in Assembly Line: DUL-DB21SSC Manufacturing Process at PT X

    Directory of Open Access Journals (Sweden)

    Gemma Eka Santoso

    2013-05-01

    goals. One advantage of cells is the one-piece flow concept, which states that each product moves through the process one unit a time without sudden interruption, at a pace determined by the customers need.

  9. The amount of ergonomics and user involvement in 151 design processes.

    Science.gov (United States)

    Kok, Barbara N E; Slegers, Karin; Vink, Peter

    2012-01-01

    Ergonomics, usability and user-centered design are terms that are well known among designers. Yet, products often seem to fail to meet the users' needs, resulting in a gap between expected and experienced usability. To understand the possible causes of this gap the actions taken by the designer during the design process are studied in this paper. This can show whether and how certain actions influence the user-friendliness of the design products. The aim of this research was to understand whether ergonomic principles and methods are included in the design process, whether users are involved in this process and whether the experience of the designer (in ergonomics/user involvement) has an effect on the end product usability. In this study the design processes of 151 tangible products of students in design were analyzed. It showed that in 75% of the cases some ergonomic principles were applied. User involvement was performed in only 1/3 of the design cases. Hardly any correlation was found between the designers' experience in ergonomic principles and the way they applied it and no correlations were found between the designers' experience in user involvement and the users' involvement in the design process.

  10. The Longitudinal Process of Early Parent Involvement on Student Achievement: A Path Analysis

    OpenAIRE

    Hayakawa, Momoko; Englund, Michelle M.; Warner-Richter, Mallory N.; Reynolds, Arthur J.

    2013-01-01

    This longitudinal study investigated the process whereby early parent involvement in preschool effects student achievement from kindergarten through 6th grade. Participants were 1,539 low-income, mainly African American children and their mothers, in the Chicago Longitudinal Study. Program children (N = 989) received one or two years of the Child-Parent Center (CPC) program – a preschool intervention that strongly promoted parents' development of parent involvement skills within the school an...

  11. The purchase decision process and involvement of the elderly regarding nonprescription products.

    Science.gov (United States)

    Reisenwitz, T H; Wimbish, G J

    1997-01-01

    The elderly or senior citizen is a large and growing market segment that purchases a disproportionate amount of health care products, particularly nonprescription products. This study attempts to examine the elderly's level of involvement (high versus low) and their purchase decision process regarding nonprescription or over-the-counter (OTC) products. Frequencies and percentages are calculated to indicate level of involvement as well as purchase decision behavior. Previous research is critiqued and managerial implications are discussed.

  12. Processes Involved in Chinese and English Writing: A Study of Chinese University Students

    Directory of Open Access Journals (Sweden)

    Meihua Liu

    2013-11-01

    Full Text Available The present study examined the writing processes of 20 L1 writers and 20 L2 writers on a course task of writing a narrative in a Chinese university naturalistic setting, as well as the challenges they encountered and their coping strategies during the processes. Analyses of the data collected via questionnaire, journal and semi-structured interviews revealed that (1 both L1 and L2 writing processes were nonlinear and cyclical, involving a constant interplay of thinking, writing, and revising throughout the process, (2 though having a lot in common, the two groups differed in many aspects regarding the foci of concern during the process of writing the narrative, (3 both groups encountered common challenges as well as those peculiar of their own writing during the composing process, and (4 both groups were resourceful learners. Based on these findings, some suggestions are discussed. Keywords: writing process; narrative; L1; L2; challenge; strategy

  13. Ultralow Pt-loading bimetallic nanoflowers: fabrication and sensing applications

    Science.gov (United States)

    Wu, Qingqing; Li, Yongxin; Xian, Hongying; Xu, Chaodi; Wang, Lun; Chen, Zhibing

    2013-01-01

    Ultralow Pt-loading Au nanoflowers (AuNFs) were synthesized on a glassy carbon electrode surface by the underpotential deposition (UPD) monolayer redox replacement technique, which involves redox replacement of a copper UPD monolayer by PtCl42- that can be reduced and deposited simultaneously. Field-emission scanning electron microscopy, energy dispersive spectroscopy, x-ray photoelectron spectroscopy and the electrochemical method were utilized to characterize the ultralow Pt-loading AuNFs. Cyclic voltammogram results showed that the ultralow Pt-loading AuNFs exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide and the oxidation of glucose in neutral media, and the reaction pathway of glucose oxidation was changed from an intermediate process based on the electrosorption of glucose to a direct oxidation process. From chronoamperometric results, it could be obtained that this prepared biosensor had wide linear ranges and very low detection limits (DLs) for H2O2 (0.025-94.3 μM DL = 0.006 μM) and glucose (0.0028-8.0 mM DL = 0.8 μM), which were much better than previous results.

  14. Usulan Indikator Evaluasi Pemasok dalam Penetapan Bidder List: Studi Kasus Pengadaan Jasa PT. Semen Padang

    Directory of Open Access Journals (Sweden)

    Pri Gustari Akbar

    2016-04-01

    Full Text Available Each company will seek to improve performance in order to obtain the optimal results and customer satisfaction. One of the factors that affect the performance of the company is the supplier or vendor, which acts as a supplier of the operational needs of the company consisting of raw materials and spare parts manufacturing equipment. The existence of suppliers is crucial for the production process and the product to be produced. Therefore, it is necessary to a proper selection of suppliers so as to eliminate all risks that would result in losses for the company. PT. Semen Padang is one of the companies involved in the cement industry is one of the members of PT. Cement Indonesia as the Holding Company. Until now both PT. Semen Padang and PT. Cement Indonesia does not have yet a standard method in the selection of suppliers for the procurement process of goods and services. This study aims to design the proposed indicator in the evaluation of suppliers to determine the bidder's list on a tender for the procurement of services in PT. Semen Padang. Based on the literature study, it obtained six criteria i.e: quality, delivery, performance history, price, technical capability, and procedural compliance, which are divided into 13 indicators of performance evaluation. These indicators will be validated by the cement industry. Future studies will design a model of evaluation of suppliers using Analytic Hierarchy Process (AHP method to determine the bidder's list on a tender for the procurement of services in PT. Semen Padang.

  15. Prostate cancer pathologic stage pT2b (2002 TNM staging system: does it exist?

    Directory of Open Access Journals (Sweden)

    Maisa M. Quintal

    2006-02-01

    Full Text Available OBJECTIVE: In the 1997 TNM staging system, tumors were classified into a single subdivision: T2a, and bilateral tumor involvement (T2b. In the 2002 TNM staging system, tumors are subclassified as T2a (less than one half of one lobe involvement, T2b (more than one half of one lobe involvement, and T2c (bilateral involvement. A recent study questioned the existence of a true pathologic pT2b tumor. The aim of our study is to verify this question. MATERIALS AND METHODS: The study population consisted of 224 men submitted to radical retropubic prostatectomy. The surgical specimens were histologically evaluated by complete embedding and whole-mount processing. Tumor extent was evaluated by a point-count method. The surgical specimens were staged according to the 2002 TNM staging system. RESULTS: Using the 2002 TNM criteria, the surgical specimens were classified as pT2a, 28 (12.50%; pT2b, 0 (0%; pT2c, 138 (61.61%; pT3a, 30 (13.39%; and, pT3b, 28 (12.50%. Using the point-count method for tumor extent evaluation, the minimum and maximum total points obtained in unilateral tumors were 192 and 368 points, respectively; the most extensive unilateral tumor showed 68 positive points (less than half the minimum total point-count. CONCLUSIONS: Using the point-count method for tumor extent, our study questions a real existence for pathologic stage pT2b tumors (unilateral tumors involving greater than one-half of one lobe.

  16. Electrodeposition and electrocatalytic activity of Pt and Pt-alloy nanoparticles and thin films on highly oriented pyrolytic graphite (HOPG)

    Science.gov (United States)

    Lu, Guojin

    Pt and Pt-based alloy catalysts were synthesized by electrodeposition on HOPG. The nucleation and growth, morphology, composition and crystal structure, and electrocatalytic activity (towards relevant reactions in the frame of PEMFCs and DMFCs) of these model electrodes were systematically investigated. The presence of chlorides inhibits the Pt reduction processes. There is a transition from progressive to instantaneous nucleation with increasing overpotential for the deposition from 1 mM H2PtCl6 electrolytes. The possibility of instantaneous nucleation at large overpotential by using electrolytes with large chloride concentration is advantageous for the growth of small, well dispersed nanoparticles. The electrochemical data were confirmed by AFM and SEM imaging studies. Relatively narrow size distributed nanoparticles can be obtained from the current system. While MOR activity decreases with decreasing particle size, the HER and HOR activity of deposited Pt particles increases with decreasing deposition period. The ORR activity first increases then decreases with increasing deposition time. Interactions between Pt and Ru, or Ni or Co are observed and they form solid solution as verified by XRD. Underpotential deposition occurs for Pt-Ni or Pt-Co co-electrodeposition. Pt-Ru deposition can be described as progressive nucleation at low overpotential and instantaneous nucleation at high overpotentials. Through direct morphological observations, the Pt-Ni or Pt-Co nucleation can be approximately described as progressive. Pt-Ru deposits are superior to Pt towards MOR. The optimum Ru content is about 50 at.%. Pt-Ni and Pt-Co deposits are more active than Pt for ORR. The optimum content is about 30 at.% Ni or 50 at.% Co. Dealloying of Pt-Ru and Pt-Ni or Pt-Co electrodeposit is observed after electrochemical characterization. The extent of dealloying increases with the content of the alloying element.

  17. [Medical certification in workers involved in logging and wood-processing].

    Science.gov (United States)

    Romankow, Jacek

    2007-01-01

    Activities involved in forestry and woodworking industry are associated with workers being exposed to numerous environmental and technology-related factors that are detrimental to their health. Such hazards include working in changeable climatic conditions, in the vicinity of heavy equipment, exposure to noise, chainsaw vibrations, enforced body positioning, hard physical work, the effect of exhaust gases, potential effects of biological factors, including epizootic diseases. Wood processing involves performing mechanical activities employing tools and machines, as well as processes utilizing various chemical substances. Forestry and woodworking industry workers may deal both with timber and with wood products. In medical certification, the following issues are of significance: work in the vicinity of rotational elements, noise, effects of chemicals or biological factors, including carcinogenic substances. For this reason, the procedures involved in medical examinations of such workers are complex.

  18. Decentralisation by Devolution: Reflections on Community Involvement in Planning Process in Tanzania

    Science.gov (United States)

    Norman, A. S.; Massoi, L.

    2010-01-01

    This paper provides reflections on Decentralization-by-Devolution in planning process at grassroots level by investigating the manner in which grassroots level is involved in preparing the three years strategic plan; and its implications towards solving socio-economic problems at grassroots level. The study employed a combined research design…

  19. Decentralisation by Devolution: Reflections on Community Involvement in Planning Process in Tanzania

    Science.gov (United States)

    Norman, A. S.; Massoi, L.

    2010-01-01

    This paper provides reflections on Decentralization-by-Devolution in planning process at grassroots level by investigating the manner in which grassroots level is involved in preparing the three years strategic plan; and its implications towards solving socio-economic problems at grassroots level. The study employed a combined research design…

  20. Reduced cortical thickness of brain areas involved in pain processing in patients with chronic pancreatitis.

    NARCIS (Netherlands)

    Frokjaer, J.B.; Bouwense, S.A.W.; Olesen, S.S.; Lundager, F.H.; Eskildsen, S.F.; Goor, H. van; Wilder-Smith, O.H.G.; Drewes, A.M.

    2012-01-01

    BACKGROUND & AIMS: Patients with painful chronic pancreatitis (CP) might have abnormal brain function. We assessed cortical thickness in brain areas involved in visceral pain processing. METHODS: We analyzed brain morphologies of 19 patients with painful CP and compared them with 15 healthy individu

  1. Stakeholder involvement in stages of a participatory process illustrated in interior design cases

    DEFF Research Database (Denmark)

    Vink, Peter; van Rhijn, Gu; Seim, Rikke

    2008-01-01

    In a previous study (Vink et al., 2008) an overview was made of the involvement of different stakeholders in a participatory design process. In this paper this overview was used to describe four participatory design cases focused on improvising productivity, health, and comfort by interior design...

  2. Investigation of heat transfer processes involved liquid impingement jets: a review

    Directory of Open Access Journals (Sweden)

    M. Molana

    2013-09-01

    Full Text Available This review reports research on liquid impingement jets and the abilities, limitations and features of this method of heat transfer. Some available and important correlations for Nusselt number are collected here. Also we demonstrate the capability of nanofluids to be applied in heat transfer processes involved liquid impingement jets.

  3. Potential processes involved in the initiation and maintenance of whiplash-associated disorders : discussion paper 3

    NARCIS (Netherlands)

    Sterling, Michele; McLean, Samuel A.; Sullivan, Michael J. L.; Elliott, James M.; Buitenhuis, Jan; Kamper, Steven J.

    2011-01-01

    Study Design. Nonsystematic review and discussion of the etiological processes involved in whiplash-associated disorders (WAD). Objective. To summarize the research and identify priorities for future research. Summary of Background Data. Although there is convergent evidence of a peripheral lesion i

  4. Music Educators' Involvement in the Individual Education Program Process and Their Knowledge of Assistive Technology

    Science.gov (United States)

    McCord, Kimberly A.; Watts, Emily H.

    2010-01-01

    In 1997, the Individuals With Disabilities Education Act of 1990 was amended to require that assistive technology be considered when preparing an individual education program (IEP). This study explored involvement of Midwestern music educators in the IEP development process as well as their knowledge and attitudes regarding use of assistive…

  5. Reflections on Practical Approaches to Involving Children and Young People in the Data Analysis Process

    Science.gov (United States)

    Coad, Jane; Evans, Ruth

    2008-01-01

    This article reflects on key methodological issues emerging from children and young people's involvement in data analysis processes. We outline a pragmatic framework illustrating different approaches to engaging children, using two case studies of children's experiences of participating in data analysis. The article highlights methods of…

  6. Parent Involvement in the College Recruiting Process: To What Extent? CERI Research Brief 2-2007

    Science.gov (United States)

    Gardner, Phil

    2010-01-01

    Parents' increasing involvement in their children's transition from college to work has grabbed the attention of the media. Every time the author talks with employer groups, he hears similar stories about the pervasive presence of parents in the recruiting process. At the same time, numerous employers questioned the presence of parents in the…

  7. Overview of mechanisms involved during the quenching and partitioning process in steels

    NARCIS (Netherlands)

    Santofimia, M.J.; Zhao, L.; Sietsma, J.

    2011-01-01

    The application of the quenching and partitioning (Q&P) process in steels involves a microstructural evolution that is more complex than just the formation of martensite followed by carbon partitioning from martensite to austenite. Examples of this complexity are the formation of epitaxial ferrite

  8. Educational Support System for Experiments Involving Construction of Sound Processing Circuits

    Science.gov (United States)

    Takemura, Atsushi

    2012-01-01

    This paper proposes a novel educational support system for technical experiments involving the production of practical electronic circuits for sound processing. To support circuit design and production, each student uses a computer during the experiments, and can learn circuit design, virtual circuit making, and real circuit making. In the…

  9. Reflections on Practical Approaches to Involving Children and Young People in the Data Analysis Process

    Science.gov (United States)

    Coad, Jane; Evans, Ruth

    2008-01-01

    This article reflects on key methodological issues emerging from children and young people's involvement in data analysis processes. We outline a pragmatic framework illustrating different approaches to engaging children, using two case studies of children's experiences of participating in data analysis. The article highlights methods of…

  10. Tightening the Purchasing Process: Superintendents Get More Involved in Buying Policies

    Science.gov (United States)

    Rivero, Victor

    2009-01-01

    Over the last 18 months, school district purchasing offices across the country have been tightening the reins like never before while more top-level administrators get involved in the budget process. "When the economy really hit the skids, states got hit hard, so a lot of school districts were forced to make severe budget cuts," says John Musso,…

  11. TRAINING DURING ISO 9001 IMPLEMENTATION AND WORKERS INVOLVEMENT INTO THE QUALITY MANAGEMENT PROCESS IN MONTENEGRO

    Directory of Open Access Journals (Sweden)

    Marc-Arthur Diaye

    2009-03-01

    Full Text Available According to several researchers, workers involvement into the implementation of a quality system in a firm is a key of its success. Since training can improve workers involvement during the implementation of a quality system in a firm, we try in this paper to evaluate quantitatively in the case of Montenegro, the impact of training of workers' involvement. Using an original data set about two leading firms from Montenegro, we show that the coefficient associated with the training variable is on average about -1.44 and is significant at a level of 1%. That is workers who are not trained during the ISO 9001 implementation are strongly less involved into the quality management process of their firms.

  12. Consumer involvement: effects on information processing from over-the-counter medication labels.

    Science.gov (United States)

    Sansgiry, S S; Cady, P S; Sansgiry, S

    2001-01-01

    The objective of this study was to evaluate the effects of consumer involvement on information processing from over-the-counter (OTC) medication labels. A sample of 256 students evaluated simulated OTC product labels for two product categories (headache and cold) in random order. Each participant evaluated labels after reading a scenario to simulate high and low involvement respectively. A questionnaire was used to collect data on variables such as label comprehension, attitude-towards-product label, product evaluation, and purchase intention. The results indicate that when consumers are involved in their purchase of OTC medications they are significantly more likely to understand information from the label and evaluate it accordingly. However, involvement does not affect attitude-towards-product label nor does it enhance purchase intention.

  13. Perancangan Sistem Supply Chain dengan Pendekatan Thinking Process of Theory of Contraint (TOC) di PT. Coca-Cola Bottling Indonesia Medan.

    OpenAIRE

    Saragih, Indra S

    2011-01-01

    PT. Coca-Cola Bottling Indonesia Medan merupakan salah satu anak perusahaan dari The Coca-Cola Company yang bergerak dalam proses pembotolan dan pendstribusian minuman ringan. Area pemasaran yang sangat luas menuntut PT. Coca-Cola Bottling Indonesia Medan harus mampu merencanakan dan mengendalikan persediaan bahan baku dan produk jadi dengan tepat untuk memenuhi permintaan dan stock produk perusahaan. Tetapi dalam pelaksanaan sistem supply chain, perusahaan belum mampu mengi...

  14. Probing the Charge Separation Process on In2S3/Pt-TiO2 Nanocomposites for Boosted Visible-light Photocatalytic Hydrogen Production

    CERN Document Server

    Wang, Fenglong; Jiang, Yijiao; Backus, Ellen H G; Bonn, Mischa; Lou, Shi Nee; Turchinovich, Dmitry; Amala, Rose

    2016-01-01

    A simple refluxing wet-chemical approach is employed for fabricating In2S3/Pt-TiO2 heterogeneous catalysts for hydrogen generation under visible light irradiation. When the mass ratio between Pt-TiO2 and cubic-phased In2S3 (denoted as In2S3/Pt-TiO2) is two, the composite catalyst shows the highest hydrogen production, which exhibits an 82-fold enhancement over in-situ deposited Pt-In2S3. UV-vis diffuse reflectance and valence band X-ray photoelectron spectra elucidate that the conduction band of In2S3 is 0.3 eV more negative compared to that of TiO2, favoring charge separation in the nanocomposites. Photoelectrochemical transient photo-current measurements and optical pump - terahertz probe spectroscopic studies further corroborate the charge separation in In2S3/Pt-TiO2. The migration of photo-induced electrons from the In2S3 conduction band to the TiO2 conduction band and subsequently into the Pt nanoparticles is found to occur within 5 picoseconds. Based on the experimental evidence, a charge separation pro...

  15. Characterization and photoactivity of Pt/N-doped TiO{sub 2} synthesized through a sol–gel process at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Bing-Shun [Feng Chia University, Green Energy Development Center (China); Tseng, Hui-Hsin [Chung Shan Medical University, School of Occupational Safety and Health (China); Su, En-Chin; Chiu, I-Ching; Wey, Ming-Yen, E-mail: mywey@dragon.nchu.edu.tw [National Chung Hsing University, Department of Environmental Engineering (China)

    2015-07-15

    The rates of photocatalytic production of H{sub 2} by Pt/N-doped TiO{sub 2} are significantly affected by the hydrolysis temperature applied during the sol–gel process. Production rates increase as the hydrolysis temperature decreases from 40 to 20 °C. The effects of the hydrolysis temperature on the properties and water-splitting behavior of photocatalysts were investigated. Characterization results showed that hydrolysis temperatures higher than 40 °C induce the formation of the rutile phase and particle agglomeration, reduce the N-dopant content, and decrease the range of visible-light absorption. In this study, a low hydrolysis temperature of about 20 °C is optimal for the sol–gel preparation of N-doped TiO{sub 2}; this temperature favors the formation of high-purity anatase, small particle size, extensive visible-light absorption, and excellent rates of photocatalytic production of H{sub 2} (about 2100 μmol h{sup −1} g{sup −1})

  16. Phosphorescent PtAu2 Complexes with Differently Positioned Carbazole-Acetylide Ligands for Solution-Processed Organic Light-Emitting Diodes with External Quantum Efficiencies of over 20.

    Science.gov (United States)

    Xu, Liang-Jin; Zeng, Xian-Chong; Wang, Jin-Yun; Zhang, Li-Yi; Chi, Yun; Chen, Zhong-Ning

    2016-08-10

    The utilization of phosphorescent metal cluster complexes as new types of emitting materials in organic light-emitting diodes (OLEDs) is becoming an alternative and viable approach for achieving high-efficiency electroluminescence. We report herein the design of cationic PtAu2 cluster complexes with differently positioned 9-phenylcarbazole-acetylides to serve as phosphorescent emitters in OLEDs. The rigid structures of PtAu2 complexes cause intense phosphorescence with quantum yields of over 85%, which originates from (3)[π(phenylcarbazole-acetylide) → π*(dpmp)] ligand-to-ligand and (3)[π(phenylcarbazole-acetylide) → p/s(PtAu2)] ligand-to-metal charge-transfer triplet excited states. When 8 wt % PtAu2 is doped to blended host materials of TCTA and OXD-7 (2:1 weight ratio) as light-emitting layers, solution-processed OLEDs give a current efficiency of 78.2 cd A(-1) and an external quantum efficiency (EQE) of 21.5% at a practical luminance of 1029 cd m(-2) with a slow efficiency roll-off upon increasing luminance. This represents the best device performance and the highest efficiency recorded at practical luminance for solution-processed OLEDs.

  17. Cochlear Implant: the complexity involved in the decision making process by the family

    Directory of Open Access Journals (Sweden)

    Sheila de Souza Vieira

    2014-06-01

    Full Text Available OBJECTIVE: to understand the meanings the family attributes to the phases of the decision-making process on a cochlear implant for their child.METHOD: qualitative research, using Symbolic Interactionism and Grounded Theory as the theoretical and methodological frameworks, respectively. Data collection instrument: semistructured interview. Nine families participated in the study (32 participants.RESULTS: knowledge deficit, difficulties to contextualize benefits and risks and fear are some factors that make this process difficult. Experiences deriving from interactions with health professionals, other cochlear implant users and their relatives strengthen decision making in favor of the implant.CONCLUSION: deciding on whether or not to have the implant involves a complex process, in which the family needs to weigh gains and losses, experience feelings of accountability and guilt, besides overcoming the risk aversion. Hence, this demands cautious preparation and knowledge from the professionals involved in this intervention.

  18. Analysis of a distributed neural system involved in spatial information, novelty, and memory processing.

    Science.gov (United States)

    Menon, V; White, C D; Eliez, S; Glover, G H; Reiss, A L

    2000-10-01

    Perceiving a complex visual scene and encoding it into memory involves a hierarchical distributed network of brain regions, most notably the hippocampus (HIPP), parahippocampal gyrus (PHG), lingual gyrus (LNG), and inferior frontal gyrus (IFG). Lesion and imaging studies in humans have suggested that these regions are involved in spatial information processing as well as novelty and memory encoding; however, the relative contributions of these regions of interest (ROIs) are poorly understood. This study investigated regional dissociations in spatial information and novelty processing in the context of memory encoding using a 2 x 2 factorial design with factors Novelty (novel vs. repeated) and Stimulus (viewing scenes with rich vs. poor spatial information). Greater activation was observed in the right than left hemisphere; however, hemispheric effects did not differ across regions, novelty, or stimulus type. Significant novelty effects were observed in all four regions. A significant ROI x Stimulus interaction was observed - spatial information processing effects were largest effects in the LNG, significant in the PHG and HIPP and nonsignificant in the IFG. Novelty processing was stimulus dependent in the LNG and stimulus independent in the PHG, HIPP, and IFG. Analysis of the profile of Novelty x Stimulus interaction across ROIs provided evidence for a hierarchical independence in novelty processing characterized by increased dissociation from spatial information processing. Despite these differences in spatial information processing, memory performance for novel scenes with rich and poor spatial information was not significantly different. Memory performance was inversely correlated with right IFG activation, suggesting the involvement of this region in strategically flawed encoding effort. Stepwise regression analysis revealed that memory encoding accounted for only a small fraction of the variance (temporal lobe activation. The implications of these results for

  19. Final report on the public involvement process phase 1, Monitored Retrievable Storage Facility Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Moore, L.; Shanteau, C.

    1992-12-01

    This report summarizes the pubic involvement component of Phase 1 of the Monitored Retrievable Storage Facility (NM) Feasibility Study in San Juan County, Utah. Part of this summary includes background information on the federal effort to locate a voluntary site for temporary storage of nuclear waste, how San Juan County came to be involved, and a profile of the county. The heart of the report, however, summarizes the activities within the public involvement process, and the issues raised in those various forums. The authors have made every effort to reflect accurately and thoroughly all the concerns and suggestions expressed to us during the five month process. We hope that this report itself is a successful model of partnership with the citizens of the county -- the same kind of partnership the county is seeking to develop with its constituents. Finally, this report offers some suggestions to both county officials and residents alike. These suggestions concern how decision-making about the county`s future can be done by a partnership of informed citizens and listening decision-makers. In the Appendix are materials relating to the public involvement process in San Juan County.

  20. Final report on the public involvement process phase 1, Monitored Retrievable Storage Facility Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Moore, L.; Shanteau, C.

    1992-12-01

    This report summarizes the pubic involvement component of Phase 1 of the Monitored Retrievable Storage Facility (NM) Feasibility Study in San Juan County, Utah. Part of this summary includes background information on the federal effort to locate a voluntary site for temporary storage of nuclear waste, how San Juan County came to be involved, and a profile of the county. The heart of the report, however, summarizes the activities within the public involvement process, and the issues raised in those various forums. The authors have made every effort to reflect accurately and thoroughly all the concerns and suggestions expressed to us during the five month process. We hope that this report itself is a successful model of partnership with the citizens of the county -- the same kind of partnership the county is seeking to develop with its constituents. Finally, this report offers some suggestions to both county officials and residents alike. These suggestions concern how decision-making about the county's future can be done by a partnership of informed citizens and listening decision-makers. In the Appendix are materials relating to the public involvement process in San Juan County.

  1. Dynamics of the YSZ-Pt Interface

    DEFF Research Database (Denmark)

    Bay, Lasse; Jacobsen, Torben

    1997-01-01

    Yttria stabilized zirconia (YSZ)-Pt point electrodes were examined by linear potential sweep, potential step and impedance measurements at 1000 degrees C in air. Inductive loops and hysteresis phenomena with long relaxation times were found. Atomic force microscopy showed changes of the interface...... between Pt and YSZ induced by the current passage. These changes involve transport of solid and are slow enough to explain the large time constants. The low frequency capacitance and inductive loop forming an entire circle indicate the presence of gas reservoirs at the YSZ-Pt interface....

  2. Invisibility and PT symmetry

    OpenAIRE

    MOSTAFAZADEH, Ali

    2013-01-01

    PHYSICAL REVIEW A 87, 012103 (2013) Invisibility and PT symmetry Ali Mostafazadeh* Department of Mathematics, Koc¸ University, Sarıyer 34450, Istanbul, Turkey (Received 9 July 2012; published 3 January 2013) For a general complex scattering potential defined on a real line, we show that the equations governing invisibility of the potential are invariant under the combined action of parity and time-reversal (PT ) transformation. We determine the PT -symmetric as well as no...

  3. Role of the Support and Reaction Conditions on the Vapor-Phase Deoxygenation of m-Cresol over Pt/C and Pt/TiO2 Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Michael B.; Ferguson, Glen A.; Ruddy, Daniel A.; Biddy, Mary J.; Beckham, Gregg T.; Schaidle, Joshua A.

    2016-04-01

    The catalytic deoxygenation of biomass fast pyrolysis vapors offers a promising route for the sustainable production of liquid transportation fuels. However, a clear understanding of the mechanistic details involved in this process has yet to be achieved, and questions remain regarding the role of the catalyst support and the influence of reaction conditions. In order to gain insight into these questions, the deoxygenation of m-cresol was investigated over Pt/C and Pt/TiO2 catalysts using experimental and computational techniques. The performance of each catalyst was evaluated in a packed-bed reactor under two conditions (523 K, 2.0 MPa and 623 K, 0.5 MPa), and the energetics of the ring hydrogenation, direct deoxygenation, and tautomerization mechanisms were calculated over hydrogen-covered Pt(111) and oxygen vacancies on the surface of TiO2(101). Over Pt(111), ring hydrogenation to 3-methylcyclohexanone and 3-methylcyclohexanol was found to be the most energetically favorable pathway. Over TiO2(101), tautomerization and direct deoxygenation to toluene were identified as additional energetically favorable routes. These calculations are consistent with the experimental data, in which Pt/TiO2 was more active on a metal site basis and exhibited higher selectivity to toluene at 623 K relative to Pt/C. On the basis of these results, it is likely that the reactivity of Pt/TiO2 and Pt/C is driven by the metallic phase at 523 K, while contributions from the TiO2 support enhance deoxygenation at 623 K. These results highlight the synergistic effects between hydrogenation catalysts and reducible metal oxide supports and provide insight into the reaction pathways responsible for their enhanced deoxygenation performance.

  4. Electrodeposited CoPt and FePt alloys nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Cagnon, L. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France)]. E-mail: laurent.cagnon@grenoble.cnrs.fr; Dahmane, Y. [Laboratoire Louis Neel, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria); Voiron, J. [Laboratoire Louis Neel, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Pairis, S. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Bacia, M. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Ortega, L. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble cedex 9 (France); Benbrahim, N. [Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria); Kadri, A. [Laboratoire de Materiaux, Electrochimie et Corrosion, BP 17, 15000 Tizi-Ouzou (Algeria)

    2007-03-15

    We have investigated CoPt and FePt alloys with the face centered tetragonal phase L10, which present very large magnetocrystalline anisotropy. Equiatomic CoPt nanowires exhibiting large coercive fields up to 1.1 T have been successfully prepared by electrodeposition into nanopores of commercial and home-made alumina membranes from a very simple electrolyte. The as-deposited material has the FCC structure with soft magnetic properties. An annealing treatment at 700 deg. C is crucial to transform this phase into the L1{sub 0} phase, which presents hard magnetic properties. Nanowires of annealed samples consist of small grains around 20 nm, with their c axes randomly distributed. The coercivity does not depend on the morphology and porosity of the two types of membranes but only on the deposited material elaborated with the appropriate thermal annealing process. Our preliminary results with FePt alloy indicate a more complicated system since the as-deposited material shows no magnetization. Magnetism appears only after annealing at 700-750 deg. C. Coercivity up to 0.85 T has been obtained at room temperature but with inhomogeneous phase composition. To achieve a single hard phase L1{sub 0}, it is essential to get for the as-deposited sample the equiatomic composition and then to employ the suitable annealing parameters (temperature and time) to change the whole FCC phase into the FCT ordered L1{sub 0} phase.

  5. Microscopic study of muon-capture transitions in nuclei involved in double-beta-decay processes

    CERN Document Server

    Kortelainen, M

    2003-01-01

    Total and partial ordinary muon-capture (OMC) rates to 1 sup + and 2 sup - states are calculated in the framework of the proton-neutron quasiparticle random-phase approximation (pnQRPA) for several nuclei involved in double-beta-decay processes. The aim is to obtain information on intermediate states involved in double-beta-decay transitions having these nuclei as either daughter or parent nuclei. It is found that the OMC observables, just like the 2 nu beta beta-decay amplitudes, strongly depend on the particle-particle part of the proton-neutron interaction. First experiments measuring the partial OMC rates for nuclei involved in double beta decays have recently been performed.

  6. Electrocatalysis of fuel cells reaction on Pt and Pt-bimetallic anode catalysts: A selective review

    Directory of Open Access Journals (Sweden)

    Stamenković Vojislav

    2002-01-01

    Full Text Available In this review we selectively summarize recent progress, primarily from our laboratory, in the development of interrelationships between the kinetics of the fuel cells reactions and the structure/composition of anode catalysts. The focus is placed on two types of metallic surfaces: platinum single crystals and bimetallic surfaces based on Pt. In the first part it was illustrated that the hydcogen reaction is structure sensitive process, with Pt(110 being an order of magnitude more active than either of the atomically "flatter" (100 and (111 surfaces. The hydrogen reaction on Pt(hkl modified by pseudomorphic Pd (submonolayers shows the "volcano-like" behavior, having the maximum rate on Pt(111 modified by 1 ML of Pd. The Pt(111-Pd system is used to demonstrate how the energetics of intermediates formed in the hydrogen reaction is affected by interfacial bonding and energetic constraints produced between pseudomorphic Pd films and the Pt(111 substrate. In the second part it was shown that the oxidation of Ha in the presence of CO occurs concurrently with CO oxidation on Pt and Pt bimetallic surfaces. The Pt-Ru system is used to demonstrate that both the bifunctional effect and the ligand effect contribute to the influence of Ru on the CO oxidation rate and for Hz oxidation process in the presence of CO. The knowledge is then used to create the real-life catalyst with the catalytic activities which are, to the greatest extend possible similar to the tailor-made surface.

  7. Combined Whole-Rock to Nano-Scale Investigations Reveal Contrasting Response of Pt-Os and Re-Os Isotope Systematics During Magmatic and Post-Magmatic Processes

    Science.gov (United States)

    Coggon, J. A.; Luguet, A.; Lorand, J. P.; Fonseca, R.; Wainwright, A.; Appel, P.; Hoffmann, J. E.; Nowell, G. M.

    2015-12-01

    Advances in single-grain and micro- and nano-analytical techniques in recent years have been particularly important to the study of highly siderophile elements (HSE) and have contributed significantly to our knowledge and understanding of their host phases and behaviour. Furthermore, whole-rock- to nano-scale studies provide new perspectives for investigation of HSE isotope systematics. Recent multi-scale 187Re-187Os and 190Pt-186Os studies facilitate comparison, to a previously unattainable degree, of the differing responses of these two decay systems to magmatic and post-magmatic processes. It is well established that mafic-ultramafic melts are sensitive to disturbance of their Re-Os isotope systematics by crustal assimilation, due to the incompatibility and resulting enrichment of Re in crustal lithologies. In contrast the very long half-life and extremely low atomic abundance of 190Pt, combined with relatively low Pt concentrations in crustal rocks, generally render the Pt-Os isotope system insensitive to modification during assimilation. However, using new single chromite grain data (Coggon et al., 2015) from the >3.811 Ga Ujaragssuit nunât layered ultramafic body, Greenland, we show that it is possible to distinguish two distinct episodes of 187Os/188Os modification; Country rock contamination of the parent melt was followed by later metamorphic disturbance of the isotope system. The Pt-Os data (Coggon et al., 2013) from the same samples show no evidence of crustal assimilation, but preserve signatures of mantle melting at ~4.1 Ga as well as disturbance during metamorphism. Macro- to micro-petrographic study clearly demonstrates that Pt, Re and Os are hosted by different mineral phases, of different origins, in these samples. This, together with the physical parameters of the decay systems reported above, leads to the dissimilar behaviour and response of the 187Re-187Os and 190Pt-186Os isotope systems during both magmatic and post-magmatic processes and

  8. Fabrication of electrodes with ultralow platinum loading by RF plasma processing of self-assembled arrays of Au@Pt nanoparticles

    Science.gov (United States)

    Banerjee, Ipshita; Kumaran, V.; Santhanam, Venugopal

    2016-07-01

    Conductive, carbon-free, electrocatalytically active, nanostructured electrodes with ultra-low platinum loading were fabricated using self-assembly of octadecanethiol-coated Au@Pt nanoparticles followed by RF plasma treatment. Bilayer arrays of Au@Pt nanoparticles with platinum loadings of 0.50, 1.04, 1.44, and 1.75 μg cm-2 (corresponding to 0.5, 1, 1.5 and 2 atomic layer coverage of platinum on nominally 5 nm gold core) were subjected to RF argon plasma treatment for various durations and their electrical conductivity, morphological evolution, and electrocatalytic activity characterized. Samples with monolayer and above platinum coverages exhibit maximum electrochemically active surface areas values of ˜100 m2/gpt and specific activities that are ˜4× to 6× of a reference platinum nanoparticle bilayer array. The underlying gold core influences the structural evolution of the samples upon RF plasma treatment and leads to the formation of highly active Pt(110) facets on the surface at an optimal plasma treatment duration, which also corresponds to the onset of a sharp decline in lateral sheet resistance. The sample having a two atom thick platinum coating has the highest total mass activity of 48 ± 3 m2/g(pt+au), corresponding to 44% Pt atom utilization, while also exhibiting enhanced CO tolerance as well as high methanol oxidation reaction and oxygen reduction reaction activity.

  9. Involving the elderly in the design process: a participatory design model for usability, safety and attractiveness

    OpenAIRE

    Demirbilek, Oya

    1999-01-01

    Ankara : Institute of Economics and Social Sciences of Bilkent University, 1999. Thesis (Ph.D.) -- Bilkent University, 1999 Includes bibliographical references leaves 113-131 This work presents a conceptual model involving the elderly users into the design process by means of participatory design sessions, where the expertise of designers and the real requirements and opinions of elderly end-users, related to how objects, environments and equipment should be designed to allow ageing ...

  10. Influence of independent risk factors on health status of persons involved in the process of education

    Directory of Open Access Journals (Sweden)

    Guriev A.V.

    2013-03-01

    Full Text Available The research goal is to increase efficiency of health education for subjects involved in the process of education. Materials: 498 questionnaires have been worked out for respondents. Methods: They have included supervision, questioning, free interviewing and methods for statistical processing of results of research. Results: The following factors have been revealed: peculiarity of leisure-time; bad quality of interaction between subjects of educational system and health care system. The characteristic of extra-curriculum risk factors has been done. Conclusion: It is stressed that the survey has determined the basic directions of training for teachers and adults to form healthy way of life.

  11. Individual reactions to high involvement work processes: investigating the role of empowerment and perceived organizational support.

    Science.gov (United States)

    Butts, Marcus M; Vandenberg, Robert J; DeJoy, David M; Schaffer, Bryan S; Wilson, Mark G

    2009-04-01

    This study sought to understand how high involvement work processes (HIWP) are processed at the employee level. Using structural equation modeling techniques, the authors tested and supported a model in which psychological empowerment mediated the effects of HIWP on job satisfaction, organizational commitment, job performance, and job stress. Furthermore, perceived organizational support (POS) was hypothesized to moderate the relationships between empowerment and these outcomes. With exception for the empowerment-job satisfaction association, support was found for our predictions. Future directions for research and the practical implications of our findings for both employees and organizations are discussed.

  12. Novel essential gene Involved in 16S rRNA processing in Escherichia coli.

    Science.gov (United States)

    Kurata, Tatsuaki; Nakanishi, Shinobu; Hashimoto, Masayuki; Taoka, Masato; Yamazaki, Yukiko; Isobe, Toshiaki; Kato, Jun-ichi

    2015-02-27

    Biogenesis of ribosomes is a complex process mediated by many factors. While its transcription proceeds, ribosomal RNA (rRNA) folds itself into a characteristic three-dimensional structure through interaction with ribosomal proteins, during which its ends are processed. Here, we show that the essential protein YqgF, a RuvC family protein with an RNase-H-like motif, is involved in the processing of pre-16S rRNA during ribosome maturation. Indeed, pre-16S rRNA accumulated in cells of a temperature-sensitive yqgF mutant (yqgF(ts)) cultured at a non-permissive temperature. In addition, purified YqgF was shown to process the 5' end of pre-16S rRNA within 70S ribosomes in vitro. Mass spectrometry analysis of the total proteins in the yqgF(ts) mutant cells showed that the expression of genes containing multiple Shine-Dalgarno-like sequences was observed to be lower than in wild type. These results are interpreted to indicate that YqgF is involved in a novel enzymic activity necessary for the processing of pre-16S rRNA, thereby affecting elongation of translation.

  13. The Thatcher illusion reveals orientation dependence in brain regions involved in processing facial expressions.

    Science.gov (United States)

    Psalta, Lilia; Young, Andrew W; Thompson, Peter; Andrews, Timothy J

    2014-01-01

    Although the processing of facial identity is known to be sensitive to the orientation of the face, it is less clear whether orientation sensitivity extends to the processing of facial expressions. To address this issue, we used functional MRI (fMRI) to measure the neural response to the Thatcher illusion. This illusion involves a local inversion of the eyes and mouth in a smiling face-when the face is upright, the inverted features make it appear grotesque, but when the face is inverted, the inversion is no longer apparent. Using an fMRI-adaptation paradigm, we found a release from adaptation in the superior temporal sulcus-a region directly linked to the processing of facial expressions-when the images were upright and they changed from a normal to a Thatcherized configuration. However, this release from adaptation was not evident when the faces were inverted. These results show that regions involved in processing facial expressions display a pronounced orientation sensitivity.

  14. Perpendicular Magnetic Anisotropy and Induced Magnetic Structures of Pt Layers in the Fe/Pt Multilayers Investigated by Resonant X-ray Magnetic Scattering

    Science.gov (United States)

    Lee, Mihee; Takechi, Ryota; Hosoito, Nobuyoshi

    2017-02-01

    Depth distribution of the magnetization induced in the paramagnetic Pt layers of Fe/Pt multilayers was investigated by resonant X-ray magnetic scattering (RXMS) near the Pt L3 absorption edge. Two samples with different perpendicular magnetic anisotropy (PMA) were chosen for RXMS measurements. The magnetic depth profile of the Pt layer was determined in the magnetic saturation state of the Fe magnetization with the sample of weak PMA. The magnetization process of the Pt layer was investigated with the sample of moderate PMA. It is found that the Pt atoms near the interface region have a perpendicular component of the induced magnetization even in the saturation state of the Fe magnetization, suggesting that the PMA of Fe/Pt multilayers originates from the Pt atoms near the interface region. Concerning the magnetization process, the induced Pt magnetization is not proportional to the Fe magnetization. This implies a complicated magnetizing mechanism of the Pt layer by the Fe magnetization.

  15. Cerâmicas ferroelétricas transparentes de PLZT e PLMN-PT: processamento e propriedades PLZT and PLMN-PT transparent ferroelectric ceramics: processing and properties

    Directory of Open Access Journals (Sweden)

    I. A. Santos

    2003-04-01

    Full Text Available Cerâmicas ferroelétricas transparentes têm sido largamente empregadas em dispositivos ópticos e eletro-ópticos. Neste trabalho apresentamos recentes progressos alcançados pelo GCFerr/DF-UFSCar na obtenção de cerâmicas ferroelétricas transparentes, obtidas por prensagem uniaxial a quente. São apresentados resultados de caracterizações microestrutural, estrutural, óptica, dielétrica, piroelétrica, eletro-óptica, eletrostrictiva e ferroelétrica, em cerâmicas de titanato zirconato de chumbo modificado com lantânio (PLZT e niobato de magnésio e chumbo - titanato de chumbo modificado com lantânio (PLMN-PT. Os resultados obtidos revelaram uma microestrutura homogênea, altos valores de densidade e ausência de fases segregadas para as cerâmicas de ambas composições. Conseqüentemente, altos valores de transmitância foram observados para as regiões visível e infravermelho próximo. As medidas elétricas também apresentaram excelentes resultados, quando comparados à literatura, demonstrando a alta qualidade das amostras obtidas.Transparent ferroelectric ceramics have been extensively employed in optical and electrooptical devices. The recent progresses achieved by the GCFerr/DF - UFSCar in the production of the transparent ferroelectric ceramics, through uniaxial hot-pressing technique, are presented. The physical property characterization, as microstructural, structural, optical, dielectrical, pyroelectric, electro-optical, electrostrictive and ferroelectric are reported for lanthanum modified lead zirconate titanate (PLZT and lanthanum modified lead magnesium niobate - lead titanate (PLMN-PT ceramics. The results revealed a homogeneous microstructure, high densities and absence of second phases for the ceramics of both compositions. Consequently, high optical transmittance was found in the visible and infrared range. The electrical measurements also presented excellent results when compared to those reported in the

  16. Has patients’ involvement in the decision‐making process changed over time?

    Science.gov (United States)

    Van Den Brink‐Muinen, Atie; Van Dulmen, Sandra M.; De Haes, Hanneke C.J.M.; Visser, Adriaan Ph.; Schellevis, François G.; Bensing, Jozien M.

    2006-01-01

    Abstract Objective  To get insight into the changes over time of patients’ involvement in the decision‐making process, and into the factors contributing to patients’ involvement and general practitioners’ (GPs) communication related to the Medical Treatment Act (MTA) issues: information about treatment, other available treatments and side‐effects; informed decision making; asking consent for treatment. Background  Societal developments have changed the doctor–patient relationship recently. Informed decision making has become a central topic. Patients’ informed consent was legalized by the MTA (1995). Design  Data of two cross‐sectional studies, the First (1987) and Second (2001) Dutch National Survey of General Practice, were compared. Setting and participants  General practice consultations; 16 GPs and 442 patients in 1987; 142 GPs and 2784 patients in 2001. Methods  Consultations were videotaped and rated using Roter's Interaction Analysis System and observer questionnaires; pre‐ and post‐consultation patient questionnaires; and GP questionnaires. Descriptive analyses and multivariate, multilevel analysis were applied. Main results  Most patients reported to have received the information they had considered as important prior to the consultation. There were discrepancies in involvement in treatment decisions and in giving information about other available treatments, side‐effects and risks. GPs who were more affective and gave more information, more often involved their patients, especially younger patients, in decision making. In 2001, more informed decision making was observed and the GPs asked consent for a treatment more often, but they less often asked for the patients’ understanding. Conclusion  Patients’ involvement in decision making has increased over time, but not in every respect. However, this does not apply for all patients, especially the older ones. It should be questioned whether they are willing or capable

  17. Stakeholders and public involvement in river management: heterogeneous acceptance of participatory processes among Swiss institutions.

    Science.gov (United States)

    Buletti, Nora; Utz, Stephan; Ejderyan, Olivier; Graefe, Olivier; Lane, Stuart; Reynard, Emmanuel

    2014-05-01

    This research explores participatory processes in the domain of river management in Switzerland. The main objective is to better understand how participatory processes are incorporated into river management practice. Switzerland being a federal state, river management is a cantonal (regional) responsibility, under the supervision (and co-funding) of the State (a Confederation). The federal funding includes the opportunity to fund additional participatory activities to aid river management, not least because the federal authorities consider the involvement of wider stakeholders and the public in decision-making as a means of aiding the progression of projects. This is a particularly important goal in a Swiss setting where direct democracy (the possibility of calling the decision of any level of government into question through a popular vote) means that a reasonable level of project acceptance is a necessary element of project progression. River management in Switzerland now includes both flood protection and river restoration objectives, which has served to increase its controversy: river corridors contain competing interests with different objectives (e.g. ecological enhancement, protection of agricultural land, flood risk reduction). We were asked by the Confederation to evaluate participatory processes it sponsored and one element of this evaluation aimed to develop a typology of stakeholder participation. We conducted interviews with the 26 cantonal officers in charge of river management. These interviews were based upon thematically structured open ended questions, with the responses analyzed qualitatively. We have identified significant divergence in the implementation of participatory processes between the cantons. These appear to be related to two factors: (1) the canton's historical experience of river management; and (2) the methods used to select stakeholders for inclusion in the decisional process. Cantons that refer to guidelines or pre

  18. Redox chemistry of H[sub 2]S oxidation by the British Gas Stretford process. Pt. 5; Aspects of the process chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, G.H.; Thompson, I. (Imperial College, London (United Kingdom). Dept.of Mineral Resources Engineering)

    1993-05-01

    Stretford processes use air to oxidize H[sub 2]S in process and natural gases to elemental sulphur, by absorption in aqueous solution at about pH9 and reaction of the resulting HS[sup -] ions with dissolved oxygen, in the presence of anthraquinone disulphonates (AQDS) and vanadium (v) species, which act as catalysts. Kinetic measurements of the reactions (AQ27DS + HS[sup -] ions), V (v) + HS([sup -]ions) and (AQ27DSH[sup -] + O[sub 2]), primarily used stopped flow spectrophotometry, as reported here, following papers on the electrochemical behaviour or the individual redox couples in Stretford Processes. The course of reaction (AQ27DS + HS [sup -] ions) was also followed with a gold bead indicator electrode, the potential of which was determined essentially by the AQ27DS/AQ27DSH[sup -] couple as the former species were reduced to the latter. (author)

  19. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1979-10-30

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  20. Sulfomethylated lignosulfonates as additives in oil recovery processes involving chemical recovery agents

    Energy Technology Data Exchange (ETDEWEB)

    Kalfoglou, G.

    1981-05-26

    A process for producing petroleum from subterranean formations is disclosed wherein production from the formation is obtained by driving a fluid from an injection well to a production well. The process involves injecting via the injection well into the formation an aqueous solution of sulfomethylated lignosulfonate salt as a sacrificial agent to inhibit the deposition of surfactant and/or polymer on the reservoir matrix. The process may best be carried out by injecting the sulfomethylated lignosulfonates into the formation through the injection well mixed with either a polymer, a surfactant solution and/or a micellar dispersion. This mixture would then be followed by a drive fluid such as water to push the chemicals to the production well.

  1. System Dynamics Modelling of the Processes Involving the Maintenance of the Naive T Cell Repertoire

    CERN Document Server

    Figueredo, Grazziela P; Whitbrook, Amanda

    2010-01-01

    The study of immune system aging, i.e. immunosenescence, is a relatively new research topic. It deals with understanding the processes of immunodegradation that indicate signs of functionality loss possibly leading to death. Even though it is not possible to prevent immunosenescence, there is great benefit in comprehending its causes, which may help to reverse some of the damage done and thus improve life expectancy. One of the main factors influencing the process of immunosenescence is the number and phenotypical variety of naive T cells in an individual. This work presents a review of immunosenescence, proposes system dynamics modelling of the processes involving the maintenance of the naive T cell repertoire and presents some preliminary results.

  2. EMPLOYEE INVOLVEMENT IN A CHANGE PROCESS - A CASE STUDY FOR ROMANIAN ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    Prediscan Mariana

    2015-07-01

    Full Text Available Innovation, competitive advantage, change are some concepts that should be on every organization's agenda, due to the fact the global market leads to global competition so in order to increase the market share, turnover or profit organizations have to incorporate those concepts in their strategies. The outside environment is very unstable and things are evolving very fast so managers from all levels have to acknowledge the importance of change and to identify as soon as possible several new ideas that should be the subject of different change processes. Openness to organizational change has become a mandatory feature for those organizations that want to survive and adapt to the external pressure, helping them to be efficient. Even if in many cases managers are the initiators of change, this process is very complex and needs support and involvement from all the members of the organization, so the employee's attitude and commitment to change is crucial. In many cases employees have a negative attitude towards change and manifest a strong resistance, due to the fact that they are not consulted and are not involved in the process of the identification for the need of change. Without understanding and knowing very well what it is expected from them, employees are afraid of the unknown and prefer to perform their tasks as they did before. Creating a climate and a culture for change is very important, because like this change will be something normal, continuous and people will feel comfortable with any change initiatives, without being surprised, confused or scared. Even if any change process should improve the current state of the organization, sometimes change efforts fail because the ones that resist change are stronger than the ones supporting change. The purpose of this paper is to analyze how often are Romanian employees involved in the processes of change and how important is the role they play. We have also tried to see the Romanian manager

  3. Relevant Factors in the Process of Socialization, Involvement and Belonging of Descendants in Family Businesses

    Directory of Open Access Journals (Sweden)

    Melquicedec Lozano-Posso

    2016-12-01

    Full Text Available This research works toward the identification of the factors that comprise the process of socialization, involvement and initial belonging of descendants in family businesses and the key relationships between them. By means of a qualitative detailed study of four cases, complemented by a quantitative survey of 274 Colombian family businesses, the authors generate a new model that takes into account both factors explored in previous research as well as others identified in this study. Findings confirm the specific dependency of each stage on the subsequent ones; socialization influences involvement, which in turn influences the belonging of the descendants to the family business, with a strong presence of factors such as knowledge, leadership, mode, timing, and motivation. Those responsible for the orientation of potential successors may examine these findings in order to optimize their preparation efforts and support of family human resources for the continuity of the business.

  4. APP processing and the APP-KPI domain involvement in the amyloid cascade.

    Science.gov (United States)

    Menéndez-González, M; Pérez-Pinera, P; Martínez-Rivera, M; Calatayud, M T; Blázquez Menes, B

    2005-01-01

    Alternative APP mRNA splicing can generate isoforms of APP containing a Kunitz protease inhibitor (KPI) domain. KPI is one of the main serine protease inhibitors. Protein and mRNA KPI(+)APP levels are elevated in Alzheimer's disease (AD) brain and are associated with increased amyloid beta deposition. In the last years increasing evidence on multiple points in the amyloid cascade where KPI(+)APP is involved has been accumulated, admitting an outstanding position in the pathogenesis of AD to the KPI domain. This review focuses on the APP processing, the molecular activity of KPI and its physiological and pathological roles and the KPI involvement in the amyloid cascade through the nerve growth factor, the lipoprotein receptor-related protein, the tumor necrosis factor-alpha converting enzyme and the Notch1 protein.

  5. [Gender centrality in the process of identity construction of women involved in drug trafficking].

    Science.gov (United States)

    Barcinski, Mariana

    2009-01-01

    The present article aims to discuss the specificities of crimes perpetrated by women, especially the female participation in drug trafficking in Rio de Janeiro, Brazil. In addition to that, it intends to distinguish female from male criminality. The study is based on reflections made through interviews conducted with eight women presenting a history of involvement in drug trafficking in the slums of Rio de Janeiro. Through a systemic discursive approach(1), the analysis investigates the micro and macro elements involved in the process of the construction of the participants' identity. Results show that women's motivations to enter, remain and drop drug trafficking are in great part determined by gender, which along with color and class shapes the roles performed and the places occupied by men and women in society.

  6. Patient involvement in a scientific advisory process: setting the research agenda for medical products.

    Science.gov (United States)

    Elberse, Janneke Elisabeth; Pittens, Carina Anna Cornelia Maria; de Cock Buning, Tjard; Broerse, Jacqueline Elisabeth Willy

    2012-10-01

    Patient involvement in scientific advisory processes could lead to more societally relevant advice. This article describes a case study wherein the Health Council of the Netherlands involved patient groups in an advisory process with a predefined focus: setting a research agenda for medical products development. A four-phase approach was developed to stimulate needs-articulation concerning future medical products for a broad range of patient groups covering 15 disease domains. 119 (expert) patients and 92 non-patient representatives were consulted using interviews and focus groups. In a facilitated way, patients appeared capable and willing to provide input useful for an advisory process. A broad range of medical products was defined serving different purposes. This study showed two dilemmas: first, finding a balance between a predefined focus and being sufficiently broad to enable patients and patient representatives to contribute, and second, finding a balance between relevance for many patients groups and saturation of data for a lower number of patient groups. By taking the context of patients' daily life as starting point patient groups provided new insights. The predefined focus was sometimes perceived as constraining. The GR considered the articulated needs constructive and incorporated patients' input in their advice to the Minister of Health.

  7. Revealing the active intermediates in the oxidation of formic acid on Au and Pt(111).

    Science.gov (United States)

    Gao, Wang; Song, Er Hong; Jiang, Qing; Jacob, Timo

    2014-08-25

    The mechanisms of formic acid (HCOOH) oxidation on Au(111) under gas-phase and electrochemical conditions was studied by using density functional theory and then compared with the analogous processes on Pt(111). Our results demonstrate that a mechanism involving a single intermediate molecule is preferred on both Au and Pt(111). Furthermore, under gas-phase conditions, HCOOH oxidation proceeds through the same mechanism (formate pathway) on Au and Pt(111), whereas under electrochemical conditions, it can take place through significantly different mechanisms (formate and/or direct pathways), depending on the applied electrode potential. Our calculations help to rationalize conflicting experimental explanations and are crucial for understanding the mechanism of this fundamental (electro-)catalytic process. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Genes involved in complex adaptive processes tend to have highly conserved upstream regions in mammalian genomes

    Directory of Open Access Journals (Sweden)

    Kohane Isaac

    2005-11-01

    Full Text Available Abstract Background Recent advances in genome sequencing suggest a remarkable conservation in gene content of mammalian organisms. The similarity in gene repertoire present in different organisms has increased interest in studying regulatory mechanisms of gene expression aimed at elucidating the differences in phenotypes. In particular, a proximal promoter region contains a large number of regulatory elements that control the expression of its downstream gene. Although many studies have focused on identification of these elements, a broader picture on the complexity of transcriptional regulation of different biological processes has not been addressed in mammals. The regulatory complexity may strongly correlate with gene function, as different evolutionary forces must act on the regulatory systems under different biological conditions. We investigate this hypothesis by comparing the conservation of promoters upstream of genes classified in different functional categories. Results By conducting a rank correlation analysis between functional annotation and upstream sequence alignment scores obtained by human-mouse and human-dog comparison, we found a significantly greater conservation of the upstream sequence of genes involved in development, cell communication, neural functions and signaling processes than those involved in more basic processes shared with unicellular organisms such as metabolism and ribosomal function. This observation persists after controlling for G+C content. Considering conservation as a functional signature, we hypothesize a higher density of cis-regulatory elements upstream of genes participating in complex and adaptive processes. Conclusion We identified a class of functions that are associated with either high or low promoter conservation in mammals. We detected a significant tendency that points to complex and adaptive processes were associated with higher promoter conservation, despite the fact that they have emerged

  9. Involvement of cortical midline structures in the processing of autobiographical information

    Science.gov (United States)

    Kaplan, Jonas; Damasio, Hanna; Damasio, Antonio

    2014-01-01

    The term autobiographical self has been used to refer to a mental state that permits reflection on self-identity and personality and the answer to related questions (Damasio, 1998). It requires the retrieval and integrated assembly of memories of facts and events that define an individual’s biography. The neural mechanisms behind this state have not been fully elucidated, but it has been suggested that cortical midline structures (CMSs) are critically involved in processing self-related information. To date, the investigation of the involvement of CMSs in autobiographical-self processes has largely focused on the comparison between self and other in relation to one domain of information, personality traits, and has yielded conflicting results. Here, we investigated how activity in CMSs varies with (1) the target of the information (self versus an acquaintance), (2) the domain of information (personality traits versus facts), and (3) differences across individuals regarding how descriptive and how important/relevant the information targeted by the questions was, and regarding the amount of memory retrieved in order to answer the questions. We used an fMRI block-design in which 19 participants answered questions about traits and biographic facts, in relation to themselves and a distant acquaintance. In addition, the participants rated the descriptiveness and importance of the information targeted by the questions, and estimated the amount of memory retrieved to answer the questions. Our results showed that CMSs were active for both facts and traits and for both self and other, and that the level of activity in the posteromedial cortices was generally higher for other than for self. Moreover, the activity in CMSs also varied with the amount of memory retrieved to answer the questions and with descriptiveness and importance of the information. These findings suggest that involvement of CMSs during the evaluation of information is not specific for self, and depends on

  10. Processing of laminin α chains generates peptides involved in wound healing and host defense.

    Science.gov (United States)

    Senyürek, Ilknur; Kempf, Wolfgang E; Klein, Gerd; Maurer, Andreas; Kalbacher, Hubert; Schäfer, Luisa; Wanke, Ines; Christ, Christina; Stevanovic, Stefan; Schaller, Martin; Rousselle, Patricia; Garbe, Claus; Biedermann, Tilo; Schittek, Birgit

    2014-01-01

    Laminins play a fundamental role in basement membrane architecture and function in human skin. The C-terminal laminin G domain-like (LG) modules of laminin α chains are modified by proteolysis to generate LG1-3 and secreted LG4-5 tandem modules. In this study, we provide evidence that skin-derived cells process and secrete biologically active peptides from the LG4-5 module of the laminin α3, α4 and α5 chain in vitro and in vivo. We show enhanced expression and processing of the LG4-5 module of laminin α3 in keratinocytes after infection and in chronic wounds in which the level of expression and further processing of the LG4-5 module correlated with the speed of wound healing. Furthermore, bacterial or host-derived proteases promote processing of laminin α3 LG4-5. On a functional level, we show that LG4-5-derived peptides play a role in wound healing. Moreover, we demonstrate that LG4-derived peptides from the α3, α4 and α5 chains have broad antimicrobial activity and possess strong chemotactic activity to mononuclear cells. Thus, the data strongly suggest a novel multifunctional role for laminin LG4-5-derived peptides in human skin and its involvement in physiological processes and pathological conditions such as inflammation, chronic wounds and skin infection.

  11. Development of A Maintenance Device for Bus-bar PT Voltage Air Switch

    Directory of Open Access Journals (Sweden)

    Zhang Xiang

    2017-01-01

    Full Text Available When PT breaks down, it takes long time of switching operation before maintenance, which seriously delays the restoration time. Based on the principle of multiple circuit, a live replacement maintenance device for PT voltage air switch is proposed. The following aspects are involved in the design of the device: the principle of device, component selection, device’s assembly and operation process. Through functional test in simulation substation and on-site installation, it is proved that the failed air switch can be lively replaced by the device without switching operation, which greatly reduces the risk on power grid caused by such faulted air switch.

  12. Effect of Thermomechanical Processing on the Microstructure, Properties, and Work Behavior of a Ti50.5 Ni29.5 Pt20 High-Temperature Shape Memory Alloy

    Science.gov (United States)

    Noebe, Ronald; Draper, Susan; Gaydosh, Darrell; Garga, Anita; Lerch, Brad; Penney, Nicholas; Begelow, Glen; Padula, Santo, II; Brown, Jeff

    2006-01-01

    TiNiPt shape memory alloys are particularly promising for use as solid state actuators in environments up to 300 C, due to a reasonable balance of properties, including acceptable work output. However, one of the challenges to commercializing a viable high-temperature shape memory alloy (HTSMA) is to establish the appropriate primary and secondary processing techniques for fabrication of the material in a required product form such as rod and wire. Consequently, a Ti(50.5)Ni(29.5)Pt20 alloy was processed using several techniques including single-pass high-temperature extrusion, multiple-pass high-temperature extrusion, and cold drawing to produce bar stock, thin rod, and fine wire, respectively. The effects of heat treatment on the hardness, grain size, room temperature tensile properties, and transformation temperatures of hot- and cold-worked material were examined. Basic tensile properties as a function of temperature and the strain-temperature response of the alloy under constant load, for the determination of work output, were also investigated for various forms of the Ti(50.5)Ni(29.5)Pt20 alloy, including fine wire.

  13. Reflective processes and competencies involved in teaching practice at university: a case study

    Directory of Open Access Journals (Sweden)

    Caetano da Costa

    2010-01-01

    Full Text Available Founded on practical rationality, this qualitative case study aimed to explore the teaching practice at university, focusing on teacher's reflections and competencies. To this end, teaching practices were described, analyzed, and interpreted. These interactions with students on a course in the pharmacy program, brought about situations involving dilemmas and learning opportunities for problem-solving and decision-making skills. Throughout the study, students were encouraged to use knowledge-in-action, reflection-in-action, and reflection-on-action, and these processes were also experienced by the teacher. Analysis of the records from classroom observation and the interviews with students and the teacher showed the fundamental role of such reflective processes, which led to attainment of the intended objectives. In this sense, the teacher's reflective practice was essential for supporting the application of each curricular component of the course.

  14. A Traveller Information System: Minimisation of the Number of Graphs’ Nodes Involved When Processing Route Requests

    Directory of Open Access Journals (Sweden)

    Bendaoud Zakaria

    2014-12-01

    Full Text Available The number of people using public transport is continuously increasing. Transport companies want to fulfil travellers’ expectations wherever possible. However, the great number of public transport companies operating in the same area can sometimes confuse travellers as to which route they should take and how to obtain the information relative to their journey. In this paper we suggest integrating several traveller information systems from different companies into the same multimodal information system, offering companies the choice not to share their data. This encourages them to join the system. Additionally, we have minimised the number of nodes involved when processing travellers’ requests in order to simplify the calculation process. To put our plan into action, we have opted for a multi-agent system coupled with the Voronoi decomposition for managing the network.

  15. Qualified public involvement in the decision making process of siting a waste repository

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Danielle Monegalha [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Coordenacao-Geral de Recursos Humanos], e-mail: drodrigues@cnen.gov.br; Almeida, Ivan Pedro Salati de [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Coordenacao-Geral de Assuntos Internacionais], e-mail: ivsalati@cnen.gov.br

    2009-07-01

    The main objective of this paper is to identify the most important characteristics required for the qualification of local communities for participating in the process of defining a specific site for a radioactive waste repository. It also compares the strategies used by Hungary, United Kingdom and Belgium to stimulate the public participation in the decision-making process of building and operating a radioactive waste repository, considering both the stepwise process and the spontaneous candidacy. Two main aspects are discussed as prerequisites to constitute a qualified public. The first aspect is how well the person or entity can be considered an effective representative of the community affected by the repository. This means the conditions the representative has to speak on behalf of the community and participate in the decision making process as its voice. The second characteristic is the level and quality of the information that the community and its representatives must have to participate actively in the decision-making process and what can be done to improve this status. Referring to the strategy to public involvement, this paper discusses the importance of transparency in the process, aiming the credibility of the entrepreneur as the first pace to gaining the confidence of the public affected by the project. Implementing an open dialog and listening to the needs and claims of the population are the first steps to being accepted as a true partner of the community. Preliminary discussions and explanations are important to introduce the subject and to reduce beliefs of false threats in the affected community. The constitution of a local committee is suggested, to act as a legal and formal channel to facilitate the partnership between local community, neighbors and the entrepreneur in order to achieve a positive result in the whole process. (author)

  16. Variation in genes involved in epigenetic processes offers insights into tropically adapted cattle diversity

    Directory of Open Access Journals (Sweden)

    Laercio R Porto-Neto

    2014-04-01

    Full Text Available We evaluated the relevance of the BovineHD Illumina SNP chip with respect to genes involved in epigenetic processes. Genotypes for 729,068 SNP on two tropical cattle breeds of Australia were used: Brahman (n = 2,112 and Tropical Composite (n = 2,550. We used data mining approaches to compile a list of bovine protein-coding genes involved in epigenetic processes. These genes represent 9 functional categories that contain between one (histone demethylases and 99 (chromatin remodelling factors genes. A total of 3,091 SNP mapped to positions within 3,000 bp of the 193 coding regions of those genes, including 113 SNP in transcribed regions, 2,738 in intronic regions and 240 in up- or down-stream regions. For all these SNP categories, we observed differences in the allelic frequencies between Brahman and Tropical Composite cattle. These differences were larger than those observed for the entire set of 729,068 SNP (P = 1.79 x 10-5. A multidimensional scaling analysis using only the 113 SNP in transcribed regions allowed for the separation of the two populations and this separation was comparable to the one obtained with a random set of 113 SNP (Principal Component 1 r2 > 0.84. To further characterise the differences between the breeds we defined a gene-differentiation metric based on the average genotypic frequencies of SNP connected to each gene and compared both cattle populations. The 10% most differentiated genes were distributed across 10 chromosomes, with significant (P < 0.05 enrichment on BTA 3 and 10. The 10% most conserved genes were located in 12 chromosomes. We conclude that there is variation between cattle populations in genes connected to epigenetic processes, and this variation can be used to differentiate cattle breeds. More research is needed to fully characterise the use of these SNP and its potential as means to further our understanding of biological variation and epigenetic processes.

  17. Variation in genes involved in epigenetic processes offers insights into tropically adapted cattle diversity

    Science.gov (United States)

    Porto-Neto, Laercio R.; Fortes, Marina R. S.; McWilliam, Sean M.; Lehnert, Sigrid A.; Reverter, Antonio

    2014-01-01

    We evaluated the relevance of the BovineHD Illumina SNP chip with respect to genes involved in epigenetic processes. Genotypes for 729,068 SNP on two tropical cattle breeds of Australia were used: Brahman (n = 2112) and Tropical Composite (n = 2550). We used data mining approaches to compile a list of bovine protein-coding genes involved in epigenetic processes. These genes represent 9 functional categories that contain between one (histone demethylases) and 99 (chromatin remodeling factors) genes. A total of 3091 SNP mapped to positions within 3000 bp of the 193 coding regions of those genes, including 113 SNP in transcribed regions, 2738 in intronic regions and 240 in up- or down-stream regions. For all these SNP categories, we observed differences in the allelic frequencies between Brahman and Tropical Composite cattle. These differences were larger than those observed for the entire set of 729,068 SNP (P = 1.79 x 10−5). A multidimensional scaling analysis using only the 113 SNP in transcribed regions allowed for the separation of the two populations and this separation was comparable to the one obtained with a random set of 113 SNP (Principal Component 1 r2 > 0.84). To further characterize the differences between the breeds we defined a gene-differentiation metric based on the average genotypic frequencies of SNP connected to each gene and compared both cattle populations. The 10% most differentiated genes were distributed across 10 chromosomes, with significant (P < 0.05) enrichment on BTA 3 and 10. The 10% most conserved genes were located in 12 chromosomes. We conclude that there is variation between cattle populations in genes connected to epigenetic processes, and this variation can be used to differentiate cattle breeds. More research is needed to fully characterize the use of these SNP and its potential as means to further our understanding of biological variation and epigenetic processes. PMID:24795751

  18. A comparison of form processing involved in the perception of biological and nonbiological movements

    Science.gov (United States)

    Thurman, Steven M.; Lu, Hongjing

    2016-01-01

    Although there is evidence for specialization in the human brain for processing biological motion per se, few studies have directly examined the specialization of form processing in biological motion perception. The current study was designed to systematically compare form processing in perception of biological (human walkers) to nonbiological (rotating squares) stimuli. Dynamic form-based stimuli were constructed with conflicting form cues (position and orientation), such that the objects were perceived to be moving ambiguously in two directions at once. In Experiment 1, we used the classification image technique to examine how local form cues are integrated across space and time in a bottom-up manner. By comparing with a Bayesian observer model that embodies generic principles of form analysis (e.g., template matching) and integrates form information according to cue reliability, we found that human observers employ domain-general processes to recognize both human actions and nonbiological object movements. Experiments 2 and 3 found differential top-down effects of spatial context on perception of biological and nonbiological forms. When a background does not involve social information, observers are biased to perceive foreground object movements in the direction opposite to surrounding motion. However, when a background involves social cues, such as a crowd of similar objects, perception is biased toward the same direction as the crowd for biological walking stimuli, but not for rotating nonbiological stimuli. The model provided an accurate account of top-down modulations by adjusting the prior probabilities associated with the internal templates, demonstrating the power and flexibility of the Bayesian approach for visual form perception. PMID:26746875

  19. Aspects of Information Architecture involved in process mapping in Military Organizations under the semiotic perspective

    Directory of Open Access Journals (Sweden)

    Mac Amaral Cartaxo

    2016-04-01

    Full Text Available Introduction: The description of the processes to represent the activities in an organization has important call semiotic, It is the flowcharts of uses, management reports and the various forms of representation of the strategies used. The subsequent interpretation of the organization's employees involved in learning tasks and the symbols used to translate the meanings of management practices is essential role for the organization. Objective: The objective of this study was to identify evidence of conceptual and empirical, on aspects of information architecture involved in the mapping process carried out in military organizations under the semiotic perspective. Methodology: The research is characterized as qualitative, case study and the data collection technique was the semi-structured interview, applied to management advisors. Results: The main results indicate that management practices described with the use of pictorial symbols and different layouts have greater impact to explain the relevance of management practices and indicators. Conclusion: With regard to the semiotic appeal, it was found that the impact of a management report is significant due to the use of signs and layout that stimulate further reading by simplifying complex concepts in tables, diagrams summarizing lengthy descriptions.

  20. On the constituent counting rules for hard exclusive processes involving multiquark states

    CERN Document Server

    Guo, Feng-Kun; Wang, Wei

    2016-01-01

    At high energies, the cross section of a hard exclusive process at finite scattering angle falls off as a negative power of the center-of-mass energy $\\sqrt{s}$. If all involved quark-gluon compositions undergo hard momentum transfers, the scaling of the fall-off is determined by the underlying valence structures of the initial and final states, known as the constituent counting rules. It was argued in the literature that the counting rules are a powerful tool to determine the valence degrees of freedom inside multiquark states when applied to exclusive production processes. However, we demonstrate that for hadrons with hidden flavors the naive application of the constituent counting rules is problematic, since it is not mandatory for all components to participate the hard scattering at the scale $\\sqrt{s}$. The correct scaling rules can be obtained easily by using effective field theory. A few examples involving the $Z_c(3900)^\\pm$ and $X(3872)$ are discussed.

  1. Diurnal rhythmicity in biological processes involved in bioavailability of functional food factors.

    Science.gov (United States)

    Tsurusaki, Takashi; Sakakibara, Hiroyuki; Aoshima, Yoshiki; Yamazaki, Shunsuke; Sakono, Masanobu; Shimoi, Kayoko

    2013-05-01

    In the past few decades, many types of functional factors have been identified in dietary foods; for example, flavonoids are major groups widely distributed in the plant kingdom. However, the absorption rates of the functional food factors are usually low, and many of these are difficult to be absorbed in the intact forms because of metabolization by biological processes during absorption. To gain adequate beneficial effects, it is therefore mandatory to know whether functional food factors are absorbed in sufficient quantity, and then reach target organs while maintaining beneficial effects. These are the reasons why the bioavailability of functional food factors has been well investigated using rodent models. Recently, many of the biological processes have been reported to follow diurnal rhythms recurring every 24 h. Therefore, absorption and metabolism of functional food factors influenced by the biological processes may vary with time of day. Consequently, the evaluation of the bioavailability of functional food factors using rodent models should take into consideration the timing of consumption. In this review, we provide a perspective overview of the diurnal rhythm of biological processes involved in the bioavailability of functional food factors, particularly flavonoids.

  2. Involvement of the endocannabinoid system in reward processing in the human brain.

    Science.gov (United States)

    van Hell, Hendrika H; Jager, Gerry; Bossong, Matthijs G; Brouwer, Annelies; Jansma, J Martijn; Zuurman, Lineke; van Gerven, Joop; Kahn, René S; Ramsey, Nick F

    2012-02-01

    Disturbed reward processing in humans has been associated with a number of disorders, such as depression, addiction, and attention-deficit hyperactivity disorder. The endocannabinoid (eCB) system has been implicated in reward processing in animals, but in humans, the relation between eCB functioning and reward is less clear. The current study uses functional magnetic resonance imaging (fMRI) to investigate the role of the eCB system in reward processing in humans by examining the effect of the eCB agonist Δ(9)-tetrahydrocannabinol (THC) on reward-related brain activity. Eleven healthy males participated in a randomized placebo-controlled pharmacological fMRI study with administration of THC to challenge the eCB system. We compared anticipatory and feedback-related brain activity after placebo and THC, using a monetary incentive delay task. In this task, subjects are notified before each trial whether a correct response is rewarded ("reward trial") or not ("neutral trial"). Subjects showed faster reaction times during reward trials compared to neutral trials, and this effect was not altered by THC. THC induced a widespread attenuation of the brain response to feedback in reward trials but not in neutral trials. Anticipatory brain activity was not affected. These results suggest a role for the eCB system in the appreciation of rewards. The involvement of the eCB system in feedback processing may be relevant for disorders in which appreciation of natural rewards may be affected such as addiction.

  3. Numerical simulations of industrial processes involving fluid dynamics, combustion and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ducrocq, J. [Air Liquide, Centre de Recherche Claude-Delorme, Jouy-en-Josas (France)

    1997-12-31

    Moving out of the scientific community research laboratories, computational fluid dynamics (CFD) software packages are now allowing industrials to analyse and optimize industrial processes involving the use of gases, liquids and even some two-phase fluids. Their attractiveness and their impact stems out from the opportunity they offer to bring insight into an existing unit, or even at the design stage, by displaying the spatial distribution of process relevant variables such as temperature, concentration. The filling of the spacing in between a two-layer window is a simple example. This new opportunity of visualisation is at times an unique way, when the process environment is an opaque one, such as liquid metal flowing into a tundish or when measurements of flows may be a long and tedious work, such as flows within water treatment basins. This environment we are to investigate in order to optimize can also be a harsh one, due to its high temperature level for example. Such are burners. But then pure fluid flow analysis, such as cold flow water models, has too many shortcomings. The description of combustion processes and of radiation become a necessary feature in order to describe thermal heat transfer or to locate `hot spots`. Such numerical models showing our oxycombustion expertise in glass melting will be presented. (author)

  4. A Grounded Theory Study of the Mentoring Process Involved With Undergraduate Athletic Training Students.

    Science.gov (United States)

    Pitney, William A; Ehlers, Greg G

    2004-12-01

    OBJECTIVE: To gain insight regarding the mentoring processes involving students enrolled in athletic training education programs and to create a mentoring model. DESIGN AND SETTING: We conducted a grounded theory study with students and mentors currently affiliated with 1 of 2 of the athletic training education programs accredited by the Commission on Accreditation of Allied Health Education Programs. PARTICIPANTS: Sixteen interviews were conducted, 13 with athletic training students and 3 with individuals identified as mentors. The students ranged in age from 20 to 24 years, with an average of 21.6 years. The mentors ranged from 24 to 38 years of age, with an average of 33.3 years. Participants were purposefully selected based on theoretic sampling and availability. DATA ANALYSIS: The transcribed interviews were analyzed using open-, axial-, and selective-coding procedures. Member checks, peer debriefings, and triangulation were used to ensure trustworthiness. RESULTS: Students who acknowledged having a mentor overwhelmingly identified their clinical instructor in this role. The open-coding procedures produced 3 categories: (1) mentoring prerequisites, (2) interpersonal foundations, and (3) educational dimensions. Mentoring prerequisites included accessibility, approachability, and protege initiative. Interpersonal foundations involved the mentor and protege having congruent values, trust, and a personal relationship. The educational dimensions category involved the mentor facilitating knowledge and skill development, encouraging professional perspectives, and individualizing learning. Although a student-certified athletic trainer relationship can be grounded in either interpersonal or educational aspects, the data support the occurrence of an authentic mentoring relationship when the dimensions coalesced. CONCLUSIONS: Potential mentors must not only be accessible but also approachable by a prospective protege. Mentoring takes initiative on behalf of a student and

  5. Microwave sinthesys and characterization of Pt and Pt-Rh-Sn electrocatalysts for ethanol oxidation

    Directory of Open Access Journals (Sweden)

    Jovanović Vladislava M.

    2011-01-01

    Full Text Available Carbon supported Pt and Pt-Rh-Sn catalysts were synthesized by microwave-polyol method in ethylene glycol solution and investigated for the ethanol electro-oxidation reaction. The catalysts were characterized in terms of structure, morphology and composition by employing XRD, STM and EDX techniques. STM analysis indicated rather uniform particles and particle size of below 2 nm for both catalysts. XRD analysis of the Pt/C catalyst revealed two phases, one with the main characteristic peaks of face centered cubic crystal structure (fcc of platinum and another related to graphite like structure of carbon support Vulcan XC-72R. However, in XRD pattern of the Pt-Rh-Sn/C catalyst diffraction peaks for Pt, Rh or Sn cannot be resolved, indicating an extremely low crystallinity. The small particle sizes and homogeneous size distributions of both catalysts should be attributed to the advantages of microwave assisted modified polyol process in ethylene glycol solution. Pt-Rh- Sn/C catalyst is highly active for the ethanol oxidation with the onset potential shifted for more than 150 mV to negative values and with currents nearly 5 times higher in comparison to Pt/C catalyst. The stability tests of the catalysts, as studied by the chronoamperometric experiments, reveal that the Pt-Rh-Sn/C catalyst is evidently less poisoned then Pt/C catalyst. The increased activity of Pt-Rh-Sn/C in comparison to Pt/C catalyst is most probably promoted by bifunctional mechanism and the electronic effect of alloyed metals.

  6. Public Involvement in Repository Site Selection for Nuclear Waste: Towards a more Dynamic View in Decision-Making Processes

    Energy Technology Data Exchange (ETDEWEB)

    Kruetli, Pius; Stauffacher, Michael; Flueeler, Thomas; Scholz, Roland W. [ETH Zuerich (Switzerland). lnst. for Human-Environment Systems (HES)

    2006-09-15

    This paper discusses possibilities of public involvement in radioactive waste management. A general overview of the radioactive waste issue is presented referring to a proposed model of the respective decision-making process. Based on the well known participation ladder by Arnstein, we differentiate various intensities of public involvement. A matrix with public involvement and the decision-making process is introduced and three prototypical patterns are discussed. We conclude that time frame, the level of public involvement and the mission have to be considered as well as techniques and the overarching context - all in all, a systematic and dynamic approach for public involvement is needed.

  7. Performance PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SbO{sub 2} for the electro-oxidation of ethanol, prepared by an alcohol-reduction process; Desempenho de eletrocatalisadores PtSnRh suportados em carbono-Sb{sub 2}O{sub 5}.SnO{sub 2} para a oxidacao eletroquimica do etanol, preparados pelo metodo de reducao por alcool

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Jose Carlos

    2013-07-01

    PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SnO{sub 2}, with metal loading of 20 wt%, were prepared by an alcohol-reduction process, using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), RhCl{sub 3}.xH{sub 2}O (Aldrich) and SnCl{sub 2}.2H{sub 2}O (Aldrich), as source of metals; Sb{sub 2}O{sub 5}.SnO{sub 2} (ATO) and carbon Vulcan XC72, as support; and ethylene glycol as reducing agent. The electrocatalysts obtained were characterized physically by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diffractograms showed which PtSnRh/C-ATO electrocatalysts had FCC structure of Pt and Pt alloys, besides several peaks associated with SnO{sub 2} and ATO. The average sizes of crystallites were between 2 and 4 nm. TEM micrographs showed a good distribution of the nanoparticles on the support. The average sizes of particles were between 2 and 3 nm, with good agreement for the average size of the crystallites. The performances of the electrocatalysts were analyzed by electrochemical techniques and in real conditions of operation using single direct ethanol fuel cell. In the chronoamperometry at 50 deg C, the electrocatalysts with carbon (85 wt%) and ATO (15 wt%) support, showed the best activity, and the atomic proportions which achieved the best results were PtSnRh(70:25:05) e (90:05:05). PtSnRh(70:25:05)/85C+15ATO electrocatalysts showed the best performance in a direct ethanol fuel cell. (author)

  8. Simple preparation of Pd-Pt nanoalloy catalysts for methanol-tolerant oxygen reduction

    Science.gov (United States)

    He, Wei; Liu, Juanying; Qiao, Yongjin; Zou, Zhiqing; Zhang, Xiaogang; Akins, Daniel L.; Yang, Hui

    Carbon-supported Pd-Pt bimetallic nanoparticles of different atomic ratios (Pd-Pt/C) have been prepared by a simple procedure involving the complexing of Pd and Pt species with sodium citrate followed by ethylene glycol reduction. As-prepared Pd-Pt alloy nanoparticles evidence a single-phase fcc disordered structure, and the degree of alloying is found to increase with Pd content. Both X-ray diffraction and transmission electron microscopy characterizations indicate that all the Pd-Pt/C catalysts possess a similar mean particle size of ca. 2.8 nm. The highest mass and specific activity of the oxygen reduction reaction (ORR) using the Pd-Pt/C catalysts are found with a Pd:Pt atomic ratio of 1:2. Moreover, all Pd-Pt alloy catalysts exhibit significantly enhanced methanol tolerance during the ORR than the Pt/C catalyst, ensuring a higher ORR performance while diminishing Pt utilization.

  9. Processes and parameters involved in modeling radionuclide transport from bedded salt repositories. Final report. Technical memorandum

    Energy Technology Data Exchange (ETDEWEB)

    Evenson, D.E.; Prickett, T.A.; Showalter, P.A.

    1979-07-01

    The parameters necessary to model radionuclide transport in salt beds are identified and described. A proposed plan for disposal of the radioactive wastes generated by nuclear power plants is to store waste canisters in repository sites contained in stable salt formations approximately 600 meters below the ground surface. Among the principal radioactive wastes contained in these canisters will be radioactive isotopes of neptunium, americium, uranium, and plutonium along with many highly radioactive fission products. A concern with this form of waste disposal is the possibility of ground-water flow occurring in the salt beds and endangering water supplies and the public health. Specifically, the research investigated the processes involved in the movement of radioactive wastes from the repository site by groundwater flow. Since the radioactive waste canisters also generate heat, temperature is an important factor. Among the processes affecting movement of radioactive wastes from a repository site in a salt bed are thermal conduction, groundwater movement, ion exchange, radioactive decay, dissolution and precipitation of salt, dispersion and diffusion, adsorption, and thermomigration. In addition, structural changes in the salt beds as a result of temperature changes are important. Based upon the half-lives of the radioactive wastes, he period of concern is on the order of a million years. As a result, major geologic phenomena that could affect both the salt bed and groundwater flow in the salt beds was considered. These phenomena include items such as volcanism, faulting, erosion, glaciation, and the impact of meteorites. CDM reviewed all of the critical processes involved in regional groundwater movement of radioactive wastes and identified and described the parameters that must be included to mathematically model their behavior. In addition, CDM briefly reviewed available echniques to measure these parameters.

  10. SELECTIVE HYDROGENATION OF CINNAMALDEHYDE WITH Pt AND Pt-Fe CATALYSTS: EFFECTS OF THE SUPPORT

    Directory of Open Access Journals (Sweden)

    A.B. da Silva

    1998-06-01

    Full Text Available Low-temperature reduced TiO2-supported Pt and Pt-Fe catalysts are much more active and selective for the liquid–phase hydrogenation of cinnamaldehyde to unsaturated cinnamyl alcohol than the corresponding carbon-supported catalysts. High-temperature reduced catalysts, where the SMSI effect should be present, are almost inactive for this reaction. There is at present no definitive explanation for this effect but an electronic metal-support interaction is most probably involved.

  11. PT-symmetric strings

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo, E-mail: paolo.amore@gmail.com [Facultad de Ciencias, CUICBAS, Universidad de Colima, Bernal Díaz del Castillo 340, Colima, Colima (Mexico); Fernández, Francisco M., E-mail: fernande@quimica.unlp.edu.ar [INIFTA (UNLP, CCT La Plata-CONICET), División Química Teórica, Diag. 113 y 64 (S/N), Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina); Garcia, Javier [INIFTA (UNLP, CCT La Plata-CONICET), División Química Teórica, Diag. 113 y 64 (S/N), Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina); Gutierrez, German [Facultad de Ciencias, CUICBAS, Universidad de Colima, Bernal Díaz del Castillo 340, Colima, Colima (Mexico)

    2014-04-15

    We study both analytically and numerically the spectrum of inhomogeneous strings with PT-symmetric density. We discuss an exactly solvable model of PT-symmetric string which is isospectral to the uniform string; for more general strings, we calculate exactly the sum rules Z(p)≡∑{sub n=1}{sup ∞}1/E{sub n}{sup p}, with p=1,2,… and find explicit expressions which can be used to obtain bounds on the lowest eigenvalue. A detailed numerical calculation is carried out for two non-solvable models depending on a parameter, obtaining precise estimates of the critical values where pair of real eigenvalues become complex. -- Highlights: •PT-symmetric Hamiltonians exhibit real eigenvalues when PT symmetry is unbroken. •We study PT-symmetric strings with complex density. •They exhibit regions of unbroken PT symmetry. •We calculate the critical parameters at the boundaries of those regions. •There are exact real sum rules for some particular complex densities.

  12. Involvement of cortical midline structures in the processing of autobiographical information

    Directory of Open Access Journals (Sweden)

    Helder F. Araujo

    2014-07-01

    Full Text Available The term autobiographical self has been used to refer to a mental state that permits reflection on self-identity and personality and the answer to related questions (Damasio, 1998. It requires the retrieval and integrated assembly of memories of facts and events that define an individual’s biography. The neural mechanisms behind this state have not been fully elucidated, but it has been suggested that cortical midline structures (CMSs are critically involved in processing self-related information. To date, the investigation of the involvement of CMSs in autobiographical-self processes has largely focused on the comparison between self and other in relation to one domain of information, personality traits, and has yielded conflicting results. Here, we investigated how activity in CMSs varies with (1 the target of the information (self versus an acquaintance, (2 the domain of information (personality traits versus facts, and (3 differences across individuals regarding how descriptive and how important/relevant the information targeted by the questions was, and regarding the amount of memory retrieved in order to answer the questions. We used an fMRI block-design in which 19 participants answered questions about traits and biographic facts, in relation to themselves and a distant acquaintance. In addition, the participants rated the descriptiveness and importance of the information targeted by the questions, and estimated the amount of memory retrieved to answer the questions. Our results showed that CMSs were active for both facts and traits and for both self and other, and that the level of activity in the posteromedial cortices was generally higher for other than for self. Moreover, the activity in CMSs also varied with the amount of memory retrieved to answer the questions and with descriptiveness and importance of the information. These findings suggest that involvement of CMSs during the evaluation of information is not specific for self

  13. Neuronal processes involved in subjective feeling emergence: oscillatory activity during an emotional monitoring task.

    Science.gov (United States)

    Dan Glauser, Elise S; Scherer, Klaus R

    2008-06-01

    Subjective feeling, defined as the conscious experience of emotion and measured by self-report, is generally used as a manipulation check in studying emotional processes, rather than being the primary focus of research. In this paper, we report a first investigation into the processes involved in the emergence of a subjective feeling. We hypothesized that the oscillatory brain activity presumed to underlie the emergence of a subjective feeling can be measured by electroencephalographic (EEG) frequency band activity, similar to what has been shown in the literature for the conscious representation of objects. Emotional reactions were induced in participants using static visual stimuli. Episodes for which participants reported a subjective feeling were compared to those that did not lead to a conscious emotional experience, in order to identify potential differences between these two kinds of reactions at the oscillatory level. Discrete wavelet transforms of the EEG signal in gamma (31-63 Hz) and beta (15-31 Hz) bands showed significant differences between these two types of reactions. In addition, whereas beta band activities were widely distributed, differences in gamma band activity were predominantly observed in the frontal and prefrontal regions. The results are interpreted and discussed in terms of the complexity of the processes required to perform the affective monitoring task. It is suggested that future work on coherent mental representation of multimodal reaction patterns leading to the emergence of conscious emotional experience should include modifications in the time window examined and an extension of the frequency range to be considered.

  14. Resistance switching mode transformation in SrRuO3/Cr-doped SrZrO3/Pt frameworks via a thermally activated Ti out-diffusion process.

    Science.gov (United States)

    Jo, Yongcheol; Jung, Kyooho; Kim, Jongmin; Woo, Hyeonseok; Han, Jaeseok; Kim, Hyungsang; Hong, Jinpyo; Lee, Jeon-Kook; Im, Hyunsik

    2014-12-08

    This work reports on a mechanism for irreversible resistive switching (RS) transformation from bipolar to unipolar RS behavior in SrRuO3 (SRO)/Cr-doped SrZrO3 (SZO:Cr)/Pt capacitor structures prepared on a Ti/SiO2/Si substrate. Counter-clockwise bipolar RS memory current-voltage (I-V) characteristics are observed within the RS voltage window of -2.5 to +1.9 V, with good endurance and retention properties. As the bias voltage increases further beyond 4 V under a forward bias, a forming process occurs resulting in irreversible RS mode transformation from bipolar to unipolar mode. This switching mode transformation is a direct consequence of thermally activated Ti out-diffusion from a Ti adhesion layer. Transition metal Ti effectively out-diffuses through the loose Pt electrode layer at high substrate temperatures, leading to the unintended formation of a thin titanium oxide (TiO(x) where x < 2) layer between the Pt electrode and the SZO:Cr layer as well as additional Ti atoms in the SZO:Cr layer. Cross-sectional scanning electron microscopy, transmission electron microscopy and Auger electron spectroscopy depth-profile measurements provided apparent evidence of the Ti out-diffusion phenomenon. We propose that the out-diffusion-induced additional Ti atoms in the SZO:Cr layer contributes to the creation of the metallic filamentary channels.

  15. Spin Hall effects in mesoscopic Pt films with high resistivity

    Science.gov (United States)

    Qin, Chuan; Luo, Yongming; Zhou, Chao; Cai, Yunjiao; Jia, Mengwen; Chen, Shuhan; Wu, Yizheng; Ji, Yi

    2016-10-01

    The energy efficiency of the spin Hall effects (SHE) can be enhanced if the electrical conductivity is decreased without sacrificing the spin Hall conductivity. The resistivity of Pt films can be increased to 150-300 µΩ · cm by mesoscopic lateral confinement, thereby decreasing the conductivity. The SHE and inverse spin Hall effects (ISHE) in these mesoscopic Pt films are explored at 10 K by using the nonlocal spin injection/detection method. All relevant physical quantities are determined in situ on the same substrate, and a quantitative approach is developed to characterize all processes effectively. Extensive measurements with various Pt thickness values reveal an upper limit for the Pt spin diffusion length: {λ\\text{pt}}   ⩽  0.8 nm. The average product of {λ\\text{pt}} and the Pt spin Hall angle {α\\text{H}} is substantial: {α\\text{H}}{λ\\text{pt}}   =  (0.142  ±  0.040) nm for 4 nm thick Pt, though a gradual decrease is observed at larger Pt thickness. The results suggest enhanced spin Hall effects in resistive mesoscopic Pt films.

  16. Description of Cognitive and Competence Processes Involved in the Levels of Reading Comprehension in College Students

    Directory of Open Access Journals (Sweden)

    Charles Romel Yáñez Botello

    2013-12-01

    Full Text Available This is a descriptive research whose main objective was to describe the cognitive processes involved in reading and its relation to different levels of reading comprehension. For doing so, it was chosen a sample of 124 college students of Bogotá city. Participants- men and women between 16 and 30 years old- were studying first semester of psychology. The Evaluation Test for Reading Comprehension by Arenas (2007 was applied in order to describe cognitive operations. Moreover, results related to comprehension levels were analyzed through the Rasch Model. Besides, the Angof Methodology was used to specify the competence levels. It was concluded that there are five levels of reading comprehension. It must be said that most of the students were classified in the literal and inferential reading levels. Finally, the findings and limitations of the research were discussed.

  17. Space Weather Monitoring for the IHY: Involving Students Worldwide in the Research Process

    Science.gov (United States)

    Scherrer, D.; Burress, B.; Ross, K.

    2008-06-01

    Our project explores how new methods of space weather data collection and networks of instruments can lead to innovative and exciting ways of involving audiences in the research process. We describe our space weather monitors, being distributed to high school students and universities worldwide for the International Heliophysical Year. The project includes a centralized data collection site, accessible to anyone with or without a monitor. Classroom materials, developed in conjunction with the Chabot Space & Science Center in California, are designed to introduce teachers and students to the Sun, space weather, the Earth's ionosphere, and how to use monitor data to encourage students to undertake "hands-on" research and gain experience with real scientific data. For more information, see \\url{http://sid-stanford.edu}.

  18. The SMC5/6 complex is involved in crucial processes during human spermatogenesis.

    Science.gov (United States)

    Verver, Dideke E; Langedijk, Nathalia S M; Jordan, Philip W; Repping, Sjoerd; Hamer, Geert

    2014-07-01

    Genome integrity is crucial for safe reproduction. Therefore, chromatin structure and dynamics should be tightly regulated during germ cell development. Chromatin structure and function are in large part determined by the structural maintenance of chromosomes (SMC) protein complexes, of which SMC5/6 recently has been shown to be involved in both spermatogonial differentiation and meiosis during mouse spermatogenesis. We therefore investigated the role of this complex in human spermatogenesis. We found SMC6 to be expressed in the human testis and present in a subset of type Adark and type Apale spermatogonia, all spermatocytes, and round spermatids. During human meiosis, SMC5/6 is located at the synaptonemal complex (SC), the XY body, and at the centromeres during meiotic metaphases. However, in contrast to mouse spermatogenesis, SMC6 is not located at pericentromeric heterochromatin in human spermatogenic cells, indicating subtle but perhaps important differences in not only SMC5/6 function but maybe also in maintenance of genomic integrity at the repetitive pericentromeric regions. Nonetheless, our data clearly indicate that the SMC5/6 complex, as shown in mice, is involved in numerous crucial processes during human spermatogenesis, such as in spermatogonial development, on the SC between synapsed chromosomes, and in DNA double-strand break repair on unsynapsed chromosomes during pachynema.

  19. RPL1, a Gene Involved in Epigenetic Processes Regulates Phenotypic Plasticity in Rice

    Institute of Scientific and Technical Information of China (English)

    Cui-Cui Zhang; Wen-Ya Yuan; Qi-Fa Zhang

    2012-01-01

    Organisms can adjust their phenotype in response to changing environmental conditions.This phenomenon is termed phenotypic plasticity.Despite its ubiquitous occurrence,there has been very little study on the molecular mechanism of phenotypic plasticity.In this study,we isolated a rice (Oryza sativa L.) mutant,rice plasticity 1 (rpl1),that displayed increased environment-dependent phenotypic variations.RPL1 was expressed in all tissues examined.The protein was localized in the nucleus and its distribution in the nucleus overlapped with heterochromatin.The rpl1 mutation led to an increase in DNA methylation on repetitive sequences and a decrease in overall histone acetylation.In addition,the mutation affected responses of the rice plant to phytohormones such as brassinosteroid,gibberellin,and cytokinin.Analysis of the putative rice brassinosteroid receptor OsBRI1,a key hormone signaling gene,indicated that RPL1 may be involved in the regulation of epigenomic modification of the gene.These data suggest that RPL1 regulated phenotypic plasticity likely through its involvement in epigenetic processes affecting responses of the plant to phytohormones.

  20. Streptomyces lunalinharesii strain 235 shows the potential to inhibit bacteria involved in biocorrosion processes.

    Science.gov (United States)

    Pacheco da Rosa, Juliana; Korenblum, Elisa; Franco-Cirigliano, Marcella Novaes; Abreu, Fernanda; Lins, Ulysses; Soares, Rosângela M A; Macrae, Andrew; Seldin, Lucy; Coelho, Rosalie R R

    2013-01-01

    Four actinomycete strains previously isolated from Brazilian soils were tested for their antimicrobial activity against Bacillus pumilus LF-4 and Desulfovibrio alaskensis NCIMB 13491, bacteria that are well known to be involved in biofilm formation and biocorrosion. Strain 235, belonging to the species Streptomyces lunalinharesii, inhibited the growth of both bacteria. The antimicrobial activity was seen over a wide range of pH, and after treatment with several chemicals and heat but not with proteinase K and trypsin. The antimicrobial substances present in the concentrated supernatant from growth media were partially characterized by SDS-PAGE and extracellular polypeptides were seen. Bands in the size range of 12 to 14.4 kDa caused antimicrobial activity. Transmission electron microscopy of D. alaskensis cells treated with the concentrated supernatant containing the antimicrobial substances revealed the formation of prominent bubbles, the spherical double-layered structures on the cell membrane, and the periplasmic space completely filled with electron-dense material. This is the first report on the production of antimicrobial substances by actinomycetes against bacteria involved in biocorrosion processes, and these findings may be of great relevance as an alternative source of biocides to those currently employed in the petroleum industry.

  1. Streptomyces lunalinharesii Strain 235 Shows the Potential to Inhibit Bacteria Involved in Biocorrosion Processes

    Directory of Open Access Journals (Sweden)

    Juliana Pacheco da Rosa

    2013-01-01

    Full Text Available Four actinomycete strains previously isolated from Brazilian soils were tested for their antimicrobial activity against Bacillus pumilus LF-4 and Desulfovibrio alaskensis NCIMB 13491, bacteria that are well known to be involved in biofilm formation and biocorrosion. Strain 235, belonging to the species Streptomyces lunalinharesii, inhibited the growth of both bacteria. The antimicrobial activity was seen over a wide range of pH, and after treatment with several chemicals and heat but not with proteinase K and trypsin. The antimicrobial substances present in the concentrated supernatant from growth media were partially characterized by SDS-PAGE and extracellular polypeptides were seen. Bands in the size range of 12 to 14.4 kDa caused antimicrobial activity. Transmission electron microscopy of D. alaskensis cells treated with the concentrated supernatant containing the antimicrobial substances revealed the formation of prominent bubbles, the spherical double-layered structures on the cell membrane, and the periplasmic space completely filled with electron-dense material. This is the first report on the production of antimicrobial substances by actinomycetes against bacteria involved in biocorrosion processes, and these findings may be of great relevance as an alternative source of biocides to those currently employed in the petroleum industry.

  2. On the constituent counting rule for hard exclusive processes involving multi-quark states

    Science.gov (United States)

    Guo, Feng-Kun; Meißner, Ulf-G.; Wang, Wei

    2017-05-01

    At high energy, the cross section at finite scattering angle of a hard exclusive process falls off as a power of the Manderstam variable s. If all involved quark-gluon compositions undergo hard momentum transfers, the fall-off scaling is determined by the underlying valence structures of the initial and final hadrons, known as the constituent counting rule. In spite of the complication due to helicity conservation, it has been argued that when applied to exclusive process with exotic multiquark states, the counting rule is a powerful way to determine the valence degrees of freedom inside hadron exotics. In this work, we demonstrate that for hadrons with hidden flavors, the naive application of the constituent counting rule to exclusive process with hadron exotic multiquark states is problematic, since it is not mandatory for all components to participate in hard scattering at the scale . We illustrate the problems in the viewpoint based on effective field theory. We clarify the misleading results that may be obtained from the constituent counting rule in exclusive processes with exotic candidates such as , , X(3872), etc. Supported in part by DFG and NSFC through funds provided to the Sino-German CRC 110 “Symmetries and the Emergence of Structure in QCD” (NSFC Grant No. 11261130311), Thousand Talents Plan for Young Professionals, Chinese Academy of Sciences (CAS) President’s International Fellowship Initiative (PIFI) (2015VMA076), National Natural Science Foundation of China (11575110, 11655002), Natural Science Foundation of Shanghai (15DZ2272100, 15ZR1423100), Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Y5KF111CJ1), and by Key Laboratory for Particle Physics, Astrophysics and Cosmology, Ministry of Education.

  3. PT quantum mechanics.

    Science.gov (United States)

    Bender, Carl M; DeKieviet, Maarten; Klevansky, S P

    2013-04-28

    PT-symmetric quantum mechanics (PTQM) has become a hot area of research and investigation. Since its beginnings in 1998, there have been over 1000 published papers and more than 15 international conferences entirely devoted to this research topic. Originally, PTQM was studied at a highly mathematical level and the techniques of complex variables, asymptotics, differential equations and perturbation theory were used to understand the subtleties associated with the analytic continuation of eigenvalue problems. However, as experiments on PT-symmetric physical systems have been performed, a simple and beautiful physical picture has emerged, and a PT-symmetric system can be understood as one that has a balanced loss and gain. Furthermore, the PT phase transition can now be understood intuitively without resorting to sophisticated mathematics. Research on PTQM is following two different paths: at a fundamental level, physicists are attempting to understand the underlying mathematical structure of these theories with the long-range objective of applying the techniques of PTQM to understanding some of the outstanding problems in physics today, such as the nature of the Higgs particle, the properties of dark matter, the matter-antimatter asymmetry in the universe, neutrino oscillations and the cosmological constant; at an applied level, new kinds of PT-synthetic materials are being developed, and the PT phase transition is being observed in many physical contexts, such as lasers, optical wave guides, microwave cavities, superconducting wires and electronic circuits. The purpose of this Theme Issue is to acquaint the reader with the latest developments in PTQM. The articles in this volume are written in the style of mini-reviews and address diverse areas of the emerging and exciting new area of PT-symmetric quantum mechanics.

  4. Facilitated workshop method to involve stakeholders and public in decision making process in radiological emergencies

    Energy Technology Data Exchange (ETDEWEB)

    Mustonen, Raimo; Sinkko, Kari [STUK-Radiation and Nuclear Safety Authority, Helsinki (Finland). Research and Environmental Surveillance; Haemaelaeinen, Raimo P. [Helsinki Univ. of Technology, Helsinki (Finland). System Analysis Laboratory

    2006-09-15

    International organisations in radiation protection have for many years recommended that key players, e.g. authorities, expert organisations, industry, producers of foodstuffs and even the public, should be involved in the planning of protective actions in case of a nuclear accident. In this work, we have developed and tested a facilitated workshop method where representatives from various fields of the society aim to identify and evaluate systematically protective actions. Decision analysis techniques have been applied in workshops in order to find out the most feasible countermeasure strategies and to make the decision making-process transparent and auditable. The work builds on case studies where it was assumed that a hypothetical accident had led to a release of considerable amounts of radionuclides and therefore various types of countermeasures should be considered. This paper provides experiences gained in several European countries on how to facilitate this kind of workshops and how modern decision analysis techniques can be applied in the decision-making process.

  5. Heterologous expression of Pycnoporus cinnabarinus cellobiose dehydrogenase in Pichia pastoris and involvement in saccharification processes

    Directory of Open Access Journals (Sweden)

    Bey Mathieu

    2011-12-01

    Full Text Available Abstract Background Cellobiose dehydrogenase (CDH is an extracellular hemoflavoenzyme produced by lignocellulose-degrading fungi including Pycnoporus cinnabarinus. We investigated the cellulolytic system of P. cinnabarinus, focusing on the involvement of CDH in the deconstruction of lignocellulosic biomass. Results First, P. cinnabarinus growth conditions were optimized for CDH production. Following growth under cellulolytic conditions, the main components secreted were cellulases, xylanases and CDH. To investigate the contribution of P. cinnabarinus secretome in saccharification processes, the Trichoderma reesei enzymatic cocktail was supplemented with the P. cinnabarinus secretome. A significant enhancement of the degradation of wheat straw was observed with (i the production of a large amount of gluconic acid, (ii increased hemicellulose degradation, and (iii increased overall degradation of the lignocellulosic material. P. cinnabarinus CDH was heterologously expressed in Pichia pastoris to obtain large amounts of pure enzyme. In a bioreactor, the recombinant CDH (rCDH expression level reached 7800 U/L. rCDH exhibited values of biochemical parameters similar to those of the natural enzyme, and was able to bind cellulose despite the absence of a carbohydrate-binding module (CBM. Following supplementation of purified rCDH to T. reesei enzymatic cocktail, formation of gluconic acid and increased hemicellulose degradation were observed, thus confirming the previous results observed with P. cinnabarinus secretome. Conclusions We demonstrate that CDH offers an attractive tool for saccharification process enhancement due to gluconic acid production from raw lignocellulosic material.

  6. Analysis of the Proteolytic Processing of ABCA3: Identification of Cleavage Site and Involved Proteases.

    Directory of Open Access Journals (Sweden)

    Nicole Hofmann

    Full Text Available ABCA3 is a lipid transporter in the limiting membrane of lamellar bodies in alveolar type II cells. Mutations in the ABCA3 gene cause respiratory distress syndrome in new-borns and childhood interstitial lung disease. ABCA3 is N-terminally cleaved by an as yet unknown protease, a process believed to regulate ABCA3 activity.The exact site where ABCA3 is cleaved was localized using mass spectrometry (MS. Proteases involved in ABCA3 processing were identified using small molecule inhibitors and siRNA mediated gene knockdown. Results were verified by in vitro digestion of a synthetic peptide substrate mimicking ABCA3's cleavage region, followed by MS analysis.We found that cleavage of ABCA3 occurs after Lys174 which is located in the proteins' first luminal loop. Inhibition of cathepsin L and, to a lesser extent, cathepsin B resulted in attenuation of ABCA3 cleavage. Both enzymes showed activity against the ABCA3 peptide in vitro with cathepsin L being more active.We show here that, like some other proteins of the lysosomal membrane, ABCA3 is a substrate of cathepsin L. Therefore, cathepsin L may represent a potential target to therapeutically influence ABCA3 activity in ABCA3-associated lung disease.

  7. Microbial community analysis involved in the aerobic/extended-idle process performing biological phosphorus removal.

    Science.gov (United States)

    Zeng, Tian-jing; Yang, Guo-jing; Wang, Dong-bo; Li, Xiao-ming; Zheng, Wei; Yang, Qi; Zeng, Guang-ming

    2013-01-01

    Recently, it has been found that biological phosphorus removal can be achieved in an aerobic/extended-idle (AEI) process using both glucose and acetate as the sole substrate. However, the microbial consortiums involved in glucose-fed and acetate-fed systems have not yet been characterized. Thus the aims of this paper were to investigate the diversities and dynamics of bacterial communities during the acclimation period, and to quantify polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) in the systems. The phylogenetic analysis showed that the microbial communities were mainly composed of phylum Proteobacteria, Bacteroidetes, Chlorobi and another six kinds of unclassified bacteria. Fluorescence in-situ hybridization (FISH) analysis revealed that PAOs and GAOs accounted for 43 ± 7 and 16 ± 3% of all bacteria in the glucose-fed system, and 19 ± 4 and 35 ± 5% of total bacteria in the acetate-fed system, respectively. The results showed that the conventional PAOs could thrive in the AEI process, and a defined anaerobic zone was not necessarily required for putative PAOs growth.

  8. Transcriptome analysis in Ceratitis capitata to unveil genes involved in ageing-maturation process

    Directory of Open Access Journals (Sweden)

    V. San Andrés

    2013-07-01

    Full Text Available The sterile insect technique (SIT is widely used in integrated programmes against the Mediterranean fruit fly, Ceratitis capitata (Wiedemann (Diptera: Tephritidae. Information on the age distribution of insects, and more particularly, the knowledge of wild female reproductive status (mature or not at the time of the sterile male release is one of the key factors for the success of the SIT. In recent years, sequencing analysis has become an important tool in molecular biology. In this work we present a genome-wide expression analysis based on SSH (substractive sequence hybridization and EST (expressed sequence tag sequencing and macroarray expression analysis to identify signature genes related to the ageing-maturing process in C. capitata, leading to the successful identification of new putative candidate genes of reproductive status in medfly that would serve as molecular markers for ageing. We have sorted out 94 unigenes from 873 single-pass ESTs, of which 57% have homology with known genes. Ageing-maturing process in C. capitata presents a marked expression pattern accompanied by the increase of transcription level of genes involved in reproduction (vitellogenins, chorion proteins and male-specific serum proteins. Other identified cDNAs (43% with a differential expression pattern would be also candidates but deserve further studies, as they belong to the unknown function class.

  9. Are cognitive "insomnia" processes involved in the development and maintenance of delayed sleep wake phase disorder?

    Science.gov (United States)

    Richardson, Cele E; Gradisar, Michael; Barbero, Sebastian C

    2016-04-01

    Although individuals with delayed sleep wake phase disorder (DSWPD) and chronic insomnia disorder (CID) share many of the same phenomenological experiences, theories relating to the development and maintenance of these disorders are distinct in focus. Unlike CID, theory relating to DSWPD is primarily physiologically based and assumes almost no cognitive pathway. However, recent research findings suggest that individuals with DSWPD also display many of the sleep-disordered cognitive processes that were previously assumed to be unique to the insomnia experience. As such, this review aims to summarise current research findings to address the question "Could cognitive processes be involved in the development and maintenance of DSWPD?" In particular, the presence of cognitive and physiological pre-sleep arousal, sleep-related attentional bias, distorted perception of sleep and daytime functioning, dysfunctional beliefs and safety behaviours will be investigated. As this emerging area of research requires a stronger evidence base, we highlight suggestions for future investigation and provide preliminary practice points for clinicians assessing and treating "insomnia" in patients with DSWPD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Axillary bud and pericycle involved in the thickening process of the rhizophore nodes in Smilax species

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    B Appezzato-da-Glória

    Full Text Available AbstractThe species of the genus Smilax, popularly known as sarsaparilla, are widely used in folk medicine due to the antirheumatic properties of its underground structures. Smilax fluminensis and S. syphilitica occur in forested areas and form thickened stems called rhizophores from which adventitious roots grow. To provide information for more accurate identification of the commercialised product and for elucidating the process of stem thickening, a morphology and anatomy study of the underground organs of the two species was conducted. The adventitious roots differ in colour and diameter depending on the stage of development. They are white and have a larger diameter in the early stages of development, but as they grow, the adventitious roots become brown and have a smaller diameter due to the disintegration of the epidermis and virtually the entire cortex. In brown roots, the covering function is then performed by the lignified endodermis and the remaining walls of the cells from the last parenchyma cortical layer. These results are similar to those found in studies of other Smilax and suggest that the anatomy of the roots can be useful for identifying fraud in commercialised materials. The thickening process of the nodal regions of the rhizophores in both species involves the activity of axillary buds and pericyclic layers.

  11. Axillary bud and pericycle involved in the thickening process of the rhizophore nodes in Smilax species.

    Science.gov (United States)

    Appezzato-da-Glória, B; Silva, J M; Soares, M K M; Soares, A N; Martins, A R

    2015-08-01

    The species of the genus Smilax, popularly known as sarsaparilla, are widely used in folk medicine due to the antirheumatic properties of its underground structures. Smilax fluminensis and S. syphilitica occur in forested areas and form thickened stems called rhizophores from which adventitious roots grow. To provide information for more accurate identification of the commercialised product and for elucidating the process of stem thickening, a morphology and anatomy study of the underground organs of the two species was conducted. The adventitious roots differ in colour and diameter depending on the stage of development. They are white and have a larger diameter in the early stages of development, but as they grow, the adventitious roots become brown and have a smaller diameter due to the disintegration of the epidermis and virtually the entire cortex. In brown roots, the covering function is then performed by the lignified endodermis and the remaining walls of the cells from the last parenchyma cortical layer. These results are similar to those found in studies of other Smilax and suggest that the anatomy of the roots can be useful for identifying fraud in commercialised materials. The thickening process of the nodal regions of the rhizophores in both species involves the activity of axillary buds and pericyclic layers.

  12. Guidelines for inclusion: Ensuring Indigenous peoples' involvement in water planning processes across South Eastern Australia

    Science.gov (United States)

    Saenz Quitian, Alejandra; Rodríguez, Gloria Amparo

    2016-11-01

    Indigenous peoples within the Murray-Darling Basin have traditionally struggled for the recognition of their cultural, social, environmental, spiritual, commercial and economic connection to the waters that they have traditionally used, as well as their right to engage in all stages of water planning processes. Despite Australian national and federal frameworks providing for the inclusion of Indigenous Australians' objectives in planning frameworks, water plans have rarely addressed these objectives in water, or the strategies to achieve them. Indeed, insufficient resources, a lack of institutional capacity in both Indigenous communities and agencies and an inadequate understanding of Indigenous people's objectives in water management have limited the extent to which Indigenous objectives are addressed in water plans within the Murray-Darling Basin. In this context, the adoption of specific guidelines to meet Indigenous requirements in relation to basin water resources is crucial to support Indigenous engagement in water planning processes. Using insights from participatory planning methods and human rights frameworks, this article outlines a set of alternative and collaborative guidelines to improve Indigenous involvement in water planning and to promote sustainable and just water allocations.

  13. Mechanisms of current conduction in Pt/BaTiO{sub 3}/Pt resistive switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Pan, R.K. [School of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Zhang, T.J., E-mail: tj65zhang@yahoo.com.cn [School of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Wang, J.Y.; Wang, J.Z. [School of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Wang, D.F. [School of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); q-Psi and Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Duan, M.G. [School of Materials Science and Engineering, Hubei University, Wuhan 430062 (China)

    2012-03-30

    The 80-nm-thickness BaTiO{sub 3} (BT) thin film was prepared on the Pt/Ti/SiO{sub 2}/Si substrate by the RF magnetron sputtering technique. The Pt/BT/Pt/Ti/SiO{sub 2}/Si structure was investigated using X-ray diffraction and scanning electron microscopy. The current-voltage characteristic measurements were performed. The bipolar resistive switching behavior was found in the Pt/BT/Pt cell. The current-voltage curves were well fitted in different voltage regions at the high resistance state (HRS) and the low resistance state (LRS), respectively. The conduction mechanisms are concluded to be Ohmic conduction and Schottky emission at the LRS, while space-charge-limited conduction and Poole-Frenkel emission at the HRS. The electroforming and switching processes were explained in terms of the valence change mechanism, in which oxygen vacancies play a key role in forming conducting paths. - Highlights: Black-Right-Pointing-Pointer Pt/BaTiO{sub 3}/Pt cell shows the bipolar resistive switching behavior. Black-Right-Pointing-Pointer The current-voltage curves were well fitted for different conduction mechanisms. Black-Right-Pointing-Pointer The electroforming and switching processes were explained.

  14. PROCESSES OF ASSIMILATION INVOLVING DENTAL STOP CONSOANTS /t, d/ IN BRASILIAN PORTUGUESE

    Directory of Open Access Journals (Sweden)

    Dermeval da HORA

    2015-06-01

    Full Text Available The major aim of this paper is to present, based on quantitative sociolinguistics, a analyse of the process of progressive assimilation that involve the dental stop consonants. First of all, one overview about the regressive assimilation, which was extensively studied in Brazilian Portuguese, will be present. Then, the contexts of progressive assimilation in the speech community of Itabaiana-PB will be analyzed. The motivation for this paper is the fact that, in the dialect from Itabaiana, the process of progressive assimilation, in words such as muito ‘many/much’ and gosto ‘like”, in which the preceding phonological context exerts influence over the following one, tend to undergo the process of regressive assimilation, such as as pote ‘pot’ and bote ‘boat’, more useful when we think about the Brazilian Portuguese. The theoretical approach underlying the research is the variation theory, or quantitative Sociolinguistics, pioneered by William Labov (1972. The data collected had already been electronically stored in the corpus from Projeto Variação Linguística da Paraíba – VALPB. The sample consists of 36 informants from the community, being stratified according to gender, age group and years of schooling. As result, the computer program Goldvarb (SANKOFF; TAGLIAMONTE; SMITH, 2005 pointed as favorite to the application of the rule: the gender (male gender, the level of schooling (no scholar historic since the primary, the following phonological context (high back vowel, the precedent phonological context (monophthong, and the tonicity (post-stressed syllable.

  15. The role of the cationic Pt sites in the adsorption properties of water and ethanol on the Pt4/Pt(111) and Pt4/CeO2(111) substrates: A density functional theory investigation

    Science.gov (United States)

    Seminovski, Yohanna; Tereshchuk, Polina; Kiejna, Adam; Da Silva, Juarez L. F.

    2016-09-01

    Finite site platinum particles, Ptn, supported on reduced or unreduced cerium oxide surfaces, i.e., CeO2-x(111) ( 0 CeO2-x has been improved in the last years; however, the identification of the active sites on the Ptn/CeO2-x(111) substrates is still far from complete. In this work, we applied density functional theory based calculations with the addition of the on-site Coulomb interactions (DFT+U) for the investigation of the active sites and the role of the Pt oxidation state on the adsorption properties of water and ethanol (probe molecules) on four selected substrates, namely, Pt(111), Pt4/Pt(111), CeO2(111), and Pt4/CeO2(111). Our results show that water and ethanol preferentially bind in the cationic sites of the base of the tetrahedron Pt4 cluster instead of the anionic lower-coordinated Pt atoms located on the cluster-top or in the surface Ce (cationic) and O (anionic) sites. The presence of the Pt4 cluster contributes to increase the adsorption energy of both molecules on Pt(111) and CeO2(111) surfaces; however, its magnitude increases less for the case of Pt4/CeO2(111). Thus, the cationic Pt sites play a crucial role in the adsorption properties of water and ethanol. Both water and ethanol bind to on-top sites via the O atom and adopt parallel and perpendicular configurations on the Pt(111) and CeO2(111) substrates, respectively, while their orientation is changed once the Pt4 cluster is involved, favoring H binding with the surface sites.

  16. Bimetallic PtSn/C catalysts obtained via SOMC/M for glycerol steam reforming.

    Science.gov (United States)

    Pastor-Pérez, Laura; Merlo, Andrea; Buitrago-Sierra, Robison; Casella, Mónica; Sepúlveda-Escribano, Antonio

    2015-12-01

    A detailed study on the preparation of bimetallic PtSn/C catalysts using surface-controlled synthesis methods, and on their catalytic performance in the glycerol steam reforming reaction has been carried out. In order to obtain these well-defined bimetallic phases, techniques derived from Surface Organometallic Chemistry on Metals (SOMC/M) were used. The preparation process involved the reaction between an organometallic compound ((C4H9)4Sn) and a supported transition metal (Pt) in a H2 atmosphere. Catalysts with Sn/Pt atomic ratios of 0.2, 0.3, 0.5, and 0.7 were obtained, and characterized using several techniques: ICP, H2 chemisorption, TEM and XPS. These systems were tested in the glycerol steam reforming varying the reaction conditions (glycerol concentration and reaction temperature). The best performance was observed for the catalysts with the lowest tin contents (PtSn0.2/C and PtSn0.3/C). It was observed that the presence of tin increased the catalysts' stability when working under more severe reaction conditions.

  17. Low-cost solution processed nano millet like structure CoS2 film superior to pt as counter electrode for quantum dot sensitized solar cells

    Science.gov (United States)

    Rao, S. Srinivasa; Punnosse, Dinah; Kim, Soo-Kyoung; Kim, Hee-Je

    2015-05-01

    Cobalt Sulfide (CoS2) counter electrodes (CE) with uniform size distribution were obtained on fluorine-doped tin oxide (FTO) substrate as counter electrodes for polysulfide redox electrolyte in CdS/CdSe/ ZnS quantum dot-sensitized solar cells (QDSSCs) by chemical bath deposition (CBD) technique. In this study, we optimized the cobalt source, deposition temperature and time in the preparation of CoS2 thin film to achieve greater conversion efficiency with strong adhesion on FTO. Relative to the platinum (Pt) electrodes, the CoS2 electrode shows a higher catalytic activity, faster electron transport and lower chargetransfer resistance, which can play a role in rendering higher power conversion efficiency. As a result, QDSSCs with the optimized CoS2 CE achieved a higher short-circuit current density of 13.08 mA cm-2, open-circuit voltage of 0.47 V, fill factor of 0.34 and overall photovoltaic conversion efficiency of 2.17% obtained under one sun illumination (100 mW cm-2). Therefore, CoS2 CE can be used as a promising CE in QDSSCs with efficiency exceeding that of high-cost Pt-based cells (1.64%). [Figure not available: see fulltext.

  18. Development of brain networks involved in spoken word processing of Mandarin Chinese

    Science.gov (United States)

    Cao, Fan; Khaild, Kainat; Lee, Rebecca; Brennan, Christine; Yang, Yanhui; Li, Kuncheng; Bolger, Donald J.; Booth, James R.

    2010-01-01

    Developmental differences in phonological and orthographic processing of Chinese spoken words were examined in 9-year-olds, 11-year-olds and adults using functional magnetic resonance imaging (fMRI). Rhyming and spelling judgments were made to two-character words presented sequentially in the auditory modality. Developmental comparisons between adults and both groups of children combined showed that age-related changes in activation in visuo-orthographic regions depended on task. There were developmental increases in left inferior temporal gyrus and right inferior occipital gyrus in the spelling task, suggesting more extensive visuo-orthographic processing in a task that required access to these representations. Conversely, there were developmental decreases in activation in left fusiform gyrus and left middle occipital gyrus in the rhyming task, suggesting that the development of reading is marked by reduced involvement of orthography in a spoken language task that does not require access to these orthographic representations. Developmental decreases may arise from the existence of extensive homophony (auditory words that have multiple spellings) in Chinese. In addition, we found that 11-year-olds and adults showed similar activation in left superior temporal gyrus across tasks, with both groups showing greater activation than 9-year-olds. This pattern suggests early development of perceptual representations of phonology. In contrast, 11-year-olds and 9-year-olds showed similar activation in left inferior frontal gyrus across tasks, with both groups showing weaker activation than adults. This pattern suggests late development of controlled retrieval and selection of lexical representations. Altogether, this study suggests differential effects of character acquisition on development of components of the language network in Chinese as compared to previous reports on alphabetic languages. PMID:20884355

  19. System Model Bias Processing Approach for Regional Coordinated States Information Involved Filtering

    Directory of Open Access Journals (Sweden)

    Zebo Zhou

    2016-01-01

    Full Text Available In the Kalman filtering applications, the conventional dynamic model which connects the states information of two consecutive epochs by state transition matrix is usually predefined and assumed to be invariant. Aiming to improve the adaptability and accuracy of dynamic model, we propose multiple historical states involved filtering algorithm. An autoregressive model is used as the dynamic model which is subsequently combined with observation model for deriving the optimal window-recursive filter formulae in the sense of minimum mean square error principle. The corresponding test statistics characteristics of system residuals are discussed in details. The test statistics of regional predicted residuals are then constructed in a time-window for model bias testing with two hypotheses, that is, the null and alternative hypotheses. Based on the innovations test statistics, we develop a model bias processing procedure including bias detection, location identification, and state correction. Finally, the minimum detectable bias and bias-to-noise ratio are both computed for evaluating the internal and external reliability of overall system, respectively.

  20. An ENU mutagenesis screen identifies novel and known genes involved in epigenetic processes in the mouse.

    Science.gov (United States)

    Daxinger, Lucia; Harten, Sarah K; Oey, Harald; Epp, Trevor; Isbel, Luke; Huang, Edward; Whitelaw, Nadia; Apedaile, Anwyn; Sorolla, Anabel; Yong, Joan; Bharti, Vandhana; Sutton, Joanne; Ashe, Alyson; Pang, Zhenyi; Wallace, Nathan; Gerhardt, Daniel J; Blewitt, Marnie E; Jeddeloh, Jeffrey A; Whitelaw, Emma

    2013-01-01

    We have used a sensitized ENU mutagenesis screen to produce mouse lines that carry mutations in genes required for epigenetic regulation. We call these lines Modifiers of murine metastable epialleles (Mommes). We report a basic molecular and phenotypic characterization for twenty of the Momme mouse lines, and in each case we also identify the causative mutation. Three of the lines carry a mutation in a novel epigenetic modifier, Rearranged L-myc fusion (Rlf), and one gene, Rap-interacting factor 1 (Rif1), has not previously been reported to be involved in transcriptional regulation in mammals. Many of the other lines are novel alleles of known epigenetic regulators. For two genes, Rlf and Widely-interspaced zinc finger (Wiz), we describe the first mouse mutants. All of the Momme mutants show some degree of homozygous embryonic lethality, emphasizing the importance of epigenetic processes. The penetrance of lethality is incomplete in a number of cases. Similarly ,abnormalities in phenotype seen in the heterozygous individuals of some lines occur with incomplete penetrance. Recent advances in sequencing enhance the power of sensitized mutagenesis screens to identify the function of previously uncharacterized factors and to discover additional functions for previously characterized proteins. The observation of incomplete penetrance of phenotypes in these inbred mutant mice, at various stages of development, is of interest. Overall, the Momme collection of mouse mutants provides a valuable resource for researchers across many disciplines.

  1. Exit of Plasmodium sporozoites from oocysts is an active process that involves the circumsporozoite protein.

    Directory of Open Access Journals (Sweden)

    2005-09-01

    Full Text Available Plasmodium sporozoites develop within oocysts residing in the mosquito midgut. Mature sporozoites exit the oocysts, enter the hemolymph, and invade the salivary glands. The circumsporozoite (CS protein is the major surface protein of salivary gland and oocyst sporozoites. It is also found on the oocyst plasma membrane and on the inner surface of the oocyst capsule. CS protein contains a conserved motif of positively charged amino acids: region II-plus, which has been implicated in the initial stages of sporozoite invasion of hepatocytes. We investigated the function of region II-plus by generating mutant parasites in which the region had been substituted with alanines. Mutant parasites produced normal numbers of sporozoites in the oocysts, but the sporozoites were unable to exit the oocysts. In in vitro as well, there was a profound delay, upon trypsin treatment, in the release of mutant sporozoites from oocysts. We conclude that the exit of sporozoites from oocysts is an active process that involves the region II-plus of CS protein. In addition, the mutant sporozoites were not infective to young rats. These findings provide a new target for developing reagents that interfere with the transmission of malaria.

  2. The role of patient involvement in the diagnostic process in internal medicine: a cognitive approach.

    Science.gov (United States)

    Lucchiari, Claudio; Pravettoni, Gabriella

    2013-07-01

    Much cognitive and clinical research has addressed clinical reasoning, pointing out that physicians often have difficulties in following a linear course when making accurate diagnoses. Some authors suspect that physicians make mistakes because they unknowingly fail to observe the laws of formal logic and that their reasoning becomes influenced by contextual factors. In this paper, we introduce some basic principles of the cognitive approach to medical decision making and we describe the cognitive balanced model. Then we discuss the relationship between construction of mental models, cognitive biases and patient involvement by the use of a clinical vignette. Medical decisions may be considered fundamentally biased since the use of judgment heuristics and a combination of cognitive-related and system-related factors limit physicians' rationality. While traditional understanding of clinical reasoning has failed to consider contextual factors, most techniques designed to avoid biases seem to fail in promoting sound and safer medical practice. In particular, we argue that an unbiased process requires the use of a cognitive balanced model, in which analytical and intuitive mind skills should be properly integrated. In order to improve medical decision making and thereby lessen incidence of adverse events, it is fundamental to include the patient perspective in a balanced model. Physicians and patients should improve their collective intelligence by sharing mental models within a framework of distributed intelligence. Copyright © 2013 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  3. What have we learned about the processes involved in the Iowa Gambling Task from developmental studies?

    Directory of Open Access Journals (Sweden)

    Mathieu eCassotti

    2014-08-01

    Full Text Available Developmental studies using the Iowa Gambling Task (IGT or child-friendly adaptations of the IGT converged in showing that children and adolescents exhibit a strong bias in favor of disadvantageous choices whereas adults learn to decide advantageously during the course of the task. In the present article, we reviewed developmental studies that used the IGT or child-friendly adaptations of the IGT to show how these findings provide a better understanding of the processes involved in decision-making under uncertainty. For instance, developmental studies have underlined that until late adolescence, the dominant strategy is to focus only on the frequency of punishment and to choose among options with infrequent losses. Indeed, school-aged children and adolescents’ choices in the IGT seem to be guided by the loss frequency leading them to fail in distinguishing between advantageous and disadvantageous options. In addition, recent developmental studies revealed that adults switch less often after losses than school-aged children and adolescents. These findings suggest that psychological tolerance to loss may facilitate learning the characteristics of each option, which in turn improves the ability to choose advantageously. In conclusion, developmental studies help us refine our understanding of decision-making.

  4. Measuring cognitive processes involved in the web search: log files, eye-movements and cued rertospective reports

    NARCIS (Netherlands)

    Argelagos, Esther; Jarodzka, Halszka; Pifarre, Manoli

    2011-01-01

    Argelagós, E., Jarodzka, H., & Pifarré, M. (2011, August). Measuring cognitive processes involved in web search: log files, eye-movements and cued retrospective reports compared. Presentation at EARLI, Exeter, UK.

  5. An Investigation into the Involvement of California Central Valley High School Students with Disabilities in the IEP Process

    Science.gov (United States)

    Anderson, Cheryle Ann

    2012-01-01

    The purpose of this study was to investigate the involvement of California Central Valley high school students with disabilities in the Individual Education Plan (IEP) process. Specifically, this study investigated the involvement of students with disabilities in the development of the IEP and IEP meetings. In addition, this study explored the…

  6. An Investigation into the Involvement of California Central Valley High School Students with Disabilities in the IEP Process

    Science.gov (United States)

    Anderson, Cheryle Ann

    2012-01-01

    The purpose of this study was to investigate the involvement of California Central Valley high school students with disabilities in the Individual Education Plan (IEP) process. Specifically, this study investigated the involvement of students with disabilities in the development of the IEP and IEP meetings. In addition, this study explored the…

  7. Theoretical investigation of water formation on Rh and Pt Surfaces

    Science.gov (United States)

    Wilke, Steffen; Natoli, Vincent; Cohen, Morrel H.

    2000-06-01

    Catalytic water formation from adsorbed H and O adatoms is a fundamental reaction step in a variety of technologically important reactions involving organic molecules. In particular, the water-formation rate determines the selectivity of the catalytic partial oxidation of methane to syngas. In this report we present a theoretical investigation of the potential-energy diagram for water formation from adsorbed O and H species on Rh(111) and Pt(111) surfaces. The study is based on accurate first-principles calculations applying density-functional theory. Our results are compared to the potential-energy diagram for this reaction inferred from experimental data by Hickman and Schmidt [AIChE. J. 39, 1164 (1993)]. The calculations essentially reproduce the scheme of Hickman and Schmidt for water formation on Rh(111) with the important difference that the OH molecule is significantly more stable than assumed by Hickman and Schmidt. On Pt(111) surfaces, however, the calculations predict a barrier to OH formation very similar to that found on Rh(111). In particular, the calculated barrier to OH formation of about 20 kcal/mol seems to contradict the small 2.5 kcal/mol barrier assumed in the Hickman-Schmidt scheme and the observed large rate of water formation on Pt. A possible explanation for the apparent discrepancy between the large calculated barrier for OH formation on Pt and the experimentally observed rapid formation of water even at low temperatures is that the active sites for water formation on Pt are at "defect" sites and not on the ideally flat terraces. A similar conclusion has been reached by Verheij and co-workers [Surf. Sci. 371, 100 (1997); Chem. Phys. Lett. 174, 449 (1990); Surf. Sci. 272, 276 (1991)], who did detailed experimental work on water formation on Pt surfaces. Analyzing our results, we develop an explicit picture of the interaction processes governing the formation of OH groups. This picture rationalizes the calculated weak dependence of OH

  8. ANALYSIS OF OIL PALM SUSTAINABLE REPLANTING MODELS, A CASE AT PT. AGROWIYANA , TUNGGUL ULU, TANJUNG JABUNG BARAT, JAMBI

    Directory of Open Access Journals (Sweden)

    Solikhin Solikhin

    2012-09-01

    Full Text Available The oil palm replanting program is becoming of importance for the next decade as some of oil palm plantations are reaching the productivity peak. This research was aimed to select the priority of oil palm replanting strategy with respect to the related factors and impacts to the share holders of PIR Trans and KPPA plantation of PT. AGROWIYANA , and to identify key success indicators of replanting model. A discriptive research methodoligy was carried out using Analytical Hierarchy Process (AHP and Focus Group Discussion (FGD involving multi stakeholders of PT. AGROWIYANA . Results of this research indicated that financial is considered as the most important factor for replanting implemention with the total cutting using standard technology as chosen replanting strategy. The funding scheme through intensive fund rising IDAPERTABUN needs to be well prepared to involve more farmer groups.Keywords: PT. AGROWIYANA , Replanting Strategy

  9. Electrochemical quartz crystal microbalance study of the electrodeposition of Co, Pt and Pt-Co alloy

    Energy Technology Data Exchange (ETDEWEB)

    Martin, A.J.; Chaparro, A.M. [CIEMAT, Avda. Complutense, 22, 28040 Madrid (Spain); Daza, L. [CIEMAT, Avda. Complutense, 22, 28040 Madrid (Spain); Instituto de Catalisis y Petroleoquimica (CSIC), C/Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain)

    2007-06-10

    The electrochemical deposition of Co, Pt and Pt-Co alloy are studied with the electrochemical quartz crystal microbalance (EQCM) on a gold substrate. Co is deposited from acidic sulphate bath containing boric acid. Different processes are identified in this bath. Electrodeposition of Co on Au substrate is observed at potentials above redox potential, underpotential deposition, most probably due to formation of a Co-Au alloy. At more cathodic potentials, below -0.5 V, metallic Co is formed. The film is completely dissolved at positive potentials during the anodic scan, probably mediated by Co(OH){sub 2}. The electrodeposition of platinum from acidic PtCl{sub 6}{sup 2-} bath occurs below the thermodynamic potential (0.74 V) with almost 100% efficiency. At potentials negative from 0.0 V the efficiency decreases due to parallel water reduction. The codeposition of Co and Pt is also studied in acidic bath. Here, the decrease of pH due to water reduction on Pt deposits gives rise to precipitation of Co(OH){sub 2}, together with the deposition of metallic Pt and Co. The films contain as major component the Pt{sub 3}Co alloy. (author)

  10. Electrochemical quartz crystal microbalance study of the electrodeposition of Co, Pt and Pt-Co alloy

    Science.gov (United States)

    Martín, A. J.; Chaparro, A. M.; Daza, L.

    The electrochemical deposition of Co, Pt and Pt-Co alloy are studied with the electrochemical quartz crystal microbalance (EQCM) on a gold substrate. Co is deposited from acidic sulphate bath containing boric acid. Different processes are identified in this bath. Electrodeposition of Co on Au substrate is observed at potentials above redox potential, underpotential deposition, most probably due to formation of a Co-Au alloy. At more cathodic potentials, below -0.5 V, metallic Co is formed. The film is completely dissolved at positive potentials during the anodic scan, probably mediated by Co(OH) 2. The electrodeposition of platinum from acidic PtCl 6 2- bath occurs below the thermodynamic potential (0.74 V) with almost 100% efficiency. At potentials negative from 0.0 V the efficiency decreases due to parallel water reduction. The codeposition of Co and Pt is also studied in acidic bath. Here, the decrease of pH due to water reduction on Pt deposits gives rise to precipitation of Co(OH) 2, together with the deposition of metallic Pt and Co. The films contain as major component the Pt 3Co alloy.

  11. Analisis Pengaruh Keterlibatan Kerja dan Kepuasan Kerja terhadap Organizational Citizenship Behavior di PT Prima Graphia Digital

    Directory of Open Access Journals (Sweden)

    Andrew Adi Saputra

    2013-11-01

    Full Text Available PT Prima Graphia Digital is a company engaged in the area of digital printing, locates at Kalibaru Timur Street IV No 5-7, Senen, Central Jakarta, Indonesia, 10460. The purpose of this research is to analyze the effect of job involvement and work satisfaction towards Organizational Citizenship Behavior in PT. Prima Graphia Digital. Research used associative method. Data used were primary and secondary data obtained through observation, interview and questionnaire distribution to 86 staffs of the company as respondents. After obtaining the data, then data were processed using Pearson correlation, simple and multiple regression. Results showed that job involvement has positive effect and is significant towards Organizational Citizenship Behavior. Similarly, work satisfaction does also have a positive effect and is significant towards Organizational Citizenship Behavior. Furthermore, job involvement and work satisfaction simultaneously have a significant effect towards Organizational Citizenship Behavior.

  12. Switching fields of high-resolution magnetic force microscope tips coated with Co, Co75Pt10Cr15, Co75Pt25, and Co50Pt50 films

    Directory of Open Access Journals (Sweden)

    Ishihara Shinji

    2014-07-01

    Full Text Available Magnetic force microscope (MFM tips are prepared by coating Si tips of 4 nm radius with Co, Co75Pt10Cr15, Co75Pt25, and Co50Pt50 (at. % films of 20 nm thickness at 300 °C. The effects of coating film material on the spatial resolution and the switching field are investigated. Higher resolutions are observed in the order of Co75Pt10Cr15 < (Co50Pt50, Co75Pt25 < Co. The Co-coated tip shows the highest resolution of 7.3 nm, which seems to be depending on a high detection sensitivity related with the magnetic moment of Co material. The saturation magnetization increases in the order of Co75Pt10Cr15 < Co50Pt50 < Co75Pt25 < Co. Higher switching fields are observed in the order of Co < Co75Pt10Cr15 < Co75Pt25 < Co50Pt50. The Co50Pt50-coated tip shows the highest switching field of 1.675±0.025 kOe, which is due to a high coercive field of the magnetic film involving L11 ordered phase with high magnetocrystalline anisotropy energy. The coercive field is recognized in the order of Co < Co75Pt10Cr15 < Co75Pt25 < Co50Pt50. A tip prepared by coating Co50Pt50 film which has high resolution and high switching field is useful for MFM observations of high-density recording media and permanent magnets.

  13. Surface enrichment of Pt in stable Pt-Ir nano-alloy particles on MgAl 2 O 4 spinel in oxidizing atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei-Zhen; Nie, Lei; Cheng, Yingwen; Kovarik, Libor; Liu, Jun; Wang, Yong

    2017-04-01

    With the capability of MgAl2O4 spinel {111} nano-facets in stabilizing small Rh, Ir and Pt particles, bimetallic Ir-Pt catalysts on the same support were investigated, aiming at further lowering the catalyst cost by substituting expensive Pt with cheaper Ir in the bulk. Small Pt-Ir nano-alloy particles (< 2nm) were successfully stabilized on the spinel {111} nano-facets as expected. Interestingly, methanol oxidative dehydrogenation (ODH) rate on the surface Pt atoms increases with oxidizing aging but decreases upon reducing treatment, where Ir is almost inactive under the same reaction conditions. Up to three times enhancement in Pt exposure was achieved when the sample was oxidized at 800 °C in air for 1 week and subsequently reduced by H2 for 2 h, demonstrating successful surface enrichment of Pt on Pt-Ir nano-alloy particles. A dynamic stabilization mechanism involving wetting\

  14. PT symmetry and supersymmetry

    CERN Document Server

    Znojil, M

    2002-01-01

    A re-formulated, non-Hermitian version of the Witten's supersymmetric quantum mechanics is presented. Its use of pseudo-Hermitian (so called PT symmetric) Hamiltonians is reviewed and illustrated via several forms of an innovated supersymmetric partnership between strongly singular ("spiked") harmonic oscillators.

  15. Radiolytic Preparation of Electrocatalysts with Pt-Co and Pt-Sn Nanoparticles for a Proton Exchange Membrane Fuel Cell

    Directory of Open Access Journals (Sweden)

    Sang Kyum Kim

    2014-01-01

    Full Text Available Nanosized Pt-Sn/VC and Pt-Co/VC electrocatalysts were prepared by a one-step radiation-induced reduction (30 kGy process using distilled water as the solvent and Vulcan XC72 as the supporting material. While the Pt-Co/VC electrodes were compared with Pt/VC (40 wt%, HiSpec 4000, in terms of their electrocatalytic activity towards the oxidation of H2, the Pt-Co/VC electrodes were evaluated in terms of their activity towards the hydrogen oxidation reaction (HOR and compared with Pt/VC (40 wt%, HiSpec 4000, Pt-Co/VC, and Pt-Sn/VC in a single cell. Additionally, the prepared electrocatalyst samples (Pt-Co/VC and Pt-Sn/VC were characterized by transmission electron microscopy (TEM, scanning electron microscope (SEM, thermogravimetric analysis (TGA, X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, electrochemical surface area (ECSA, and fuel cell polarization performance.

  16. Flowerlike PtCl 4/Bi 2WO 6 composite photocatalyst with enhanced visible-light-induced photocatalytic activity

    Science.gov (United States)

    Duan, Fang; Zheng, Yan; Chen, MingQing

    2011-01-01

    Flowerlike PtCl 4/Bi 2WO 6 composite photocatalyst was successfully synthesized through a simple two-step method involving a template-free hydrothermal process and the following impregnation treatment. The samples were fully characterized by the study of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and UV-Vis absorption spectra. The results indicated that the doping of Pt species did not affect the crystal structure and the morphology of Bi 2WO 6 photocatalyst, but it had great influences on the photocatalytic activity of Bi 2WO 6 towards rhodamine-B (RhB) degradation. Besides, the Pt species was found to be present as PtCl 4 in the composite samples, and also an optimal Pt species content on the surface of Bi 2WO 6 photocatalyst was discovered with the highest photocatalytic ability. The improved photocatalytic performance could be ascribed to the enhanced interfacial charge transfer and the inhibited recombination of electron-hole pairs. Meanwhile, a possible mechanism for RhB photocatalytic degradation over PtCl 4/Bi 2WO 6 catalyst was also proposed.

  17. Evaluating the Training, Responsibilities, and Practices of P&T Committee Members and Nonmember Contributors.

    Science.gov (United States)

    Rodriguez, Ryan; Kelly, Brett J; Moody, Mary

    2017-08-01

    Pharmacy and therapeutics (P&T) committees are responsible for managing drug formularies in numerous health care settings. Although pharmacy practice and health care organizations provide general recommendations of responsibilities and skills for members and nonmember contributors of P&T committees, the study investigators hypothesized that there is diversity in the training, responsibilities, and practices of these members and contributors. To describe the training, responsibilities, and practices of members and nonmember contributors of P&T committees in a variety of health care settings, using an online survey. In December 2015, an online survey was delivered to clinicians who were considered likely to be involved in P&T committee service from hospitals ranked by U.S. News & World Report and a convenience sample of clinicians practicing in managed care settings. The survey instrument was designed to assess various domains and perceptions of P&T committee processes. Sixty-nine respondents representing various health care delivery settings in the United States were eligible for and completed the survey. The majority of the respondents were pharmacists (94.2%), and 72.5% of the respondents were P&T committee members. The remainder of the respondents were nonmember P&T committee contributors. Approximately 60% of the respondents had served in P&T committee roles for ≥ 10 years. Specialized postgraduate training incorporating literature evaluation and formulary management was possessed by 21.7% and 17.4% of the respondents, respectively; however, most of the respondents received on-the-job training. Approximately half of the respondents were responsible for preparation of P&T committee documents, and 58% reported that nonmember contributors typically write and prepare these documents. Skill in literature evaluation was the most important criterion in selecting authors of P&T committee documents, while 10.1% of the respondents indicated that their committees did not

  18. Pt-Ni and Pt-Co Catalyst Synthesis Route for Fuel Cell Applications

    Science.gov (United States)

    Firdosy, Samad A.; Ravi, Vilupanur A.; Valdez, Thomas I.; Kisor, Adam; Narayan, Sri R.

    2013-01-01

    Oxygen reduction reactions (ORRs) at the cathode are the rate-limiting step in fuel cell performance. The ORR is 100 times slower than the corresponding hydrogen oxidation at the anode. Speeding up the reaction at the cathode will improve fuel cell efficiency. The cathode material is generally Pt powder painted onto a substrate (e.g., graphite paper). Recent efforts in the fuel cell area have focused on replacing Pt with Pt-X alloys (where X = Co, Ni, Zr, etc.) in order to (a) reduce cost, and (b) increase ORR rates. One of these strategies is to increase ORR rates by reducing the powder size, which would result in an increase in the surface area, thereby facilitating faster reaction rates. In this work, a process has been developed that creates Pt-Ni or Pt-Co alloys that are finely divided (on the nano scale) and provide equivalent performance at lower Pt loadings. Lower Pt loadings will translate to lower cost. Precursor salts of the metals are dissolved in water and mixed. Next, the salt mixtures are dried on a hot plate. Finally, the dried salt mixture is heattreated in a furnace under flowing reducing gas. The catalyst powder is then used to fabricate a membrane electrode assembly (MEA) for electrochemical performance testing. The Pt- Co catalyst-based MEA showed comparable performance to an MEA fabri cated using a standard Pt black fuel cell catalyst. The main objective of this program has been to increase the overall efficiencies of fuel cell systems to support power for manned lunar bases. This work may also have an impact on terrestrial programs, possibly to support the effort to develop a carbon-free energy source. This catalyst can be used to fabricate high-efficiency fuel cell units that can be used in space as regenerative fuel cell systems, and terrestrially as primary fuel cells. Terrestrially, this technology will become increasingly important when transition to a hydrogen economy occurs.

  19. Negative P-T slopes characterize phase change processes: Case of the Ge1Sb2Te4 phase change alloy

    Science.gov (United States)

    Kalkan, B.; Sen, S.; Aitken, B. G.; Raju, S. V.; Clark, S. M.

    2011-07-01

    The crystalline, liquid and amorphous phase stabilities and transformations of the Ge1Sb2Te4 (GST124) alloy are investigated as a function of pressure and temperature using synchrotron diffraction experiments in a diamond anvil cell. The results indicate that the solid-state amorphization of the cubic GST124 phase under high pressure may correspond to a metastable extension of the stability field of the GST124 liquid along a hexagonal crystal-liquid phase boundary with a negative P-T slope. The internal pressures generated during phase change are shown to be too small to affect phase stability. However, they may be important in understanding reliability issues related to thermomechanical stress development in phase change random access memory structures.

  20. It’s all about mechanisms - what Process-tracing case studies should be tracing

    DEFF Research Database (Denmark)

    Beach, Derek

    2016-01-01

    and discord about what causal mechanisms actually are. The result of this ambiguity about what mechanisms are clearly maps onto existing applications of PT, with most PT case studies largely ignoring the underlying theoretical causal processes; i.e. it is black-boxed.This article attempts to provide a clear......It is widely agreed that the core of Process-tracing (PT) as a distinct case study methodology is that it involves tracing causal mechanisms that link causes (X) with their effects (i.e. outcomes) (Y). Yet when we look at the methodological literature on PT, there is considerable ambiguity...... definition of causal mechanisms that provides scholars using PT with a framework for theorizing mechanisms in a fashion that is amenable to in-depth empirical analysis. I contend that PT needs to adopt an understanding of causal mechanisms where they are explicitly fleshed out by unpacking causal processes...

  1. Active pharmaceutical ingredient (API) production involving continuous processes – A process system engineering (PSE)-assisted design framework

    DEFF Research Database (Denmark)

    Cervera Padrell, Albert Emili; Skovby, Tommy; Kiil, Søren

    2012-01-01

    A systematic framework is proposed for the design of continuous pharmaceutical manufacturing processes. Specifically, the design framework focuses on organic chemistry based, active pharmaceutical ingredient (API) synthetic processes, but could potentially be extended to biocatalytic and fermenta...

  2. Institutional and strategic choice perspectives on board involvement in the strategic decision process.

    Science.gov (United States)

    Judge, W Q; Zeithaml, C P

    1992-10-01

    The level of a board of directors' involvement in strategic decisions can be viewed as an institutional response or as a strategic adaptation to external pressures for greater board involvement. We examined the antecedents and effects of board involvement from both the institutional and strategic choice perspectives. Data obtained from personal interviews with 114 board members and archival records indicated that board size and levels of diversification and insider representation were negatively related to board involvement, and organizational age was positively related to it. Furthermore, we found board involvement to be positively related to financial performance after controlling for industry and size effects. Overall, the results suggest that both theoretical perspectives are necessary for a comprehensive description of the strategic role of boards.

  3. Integrating Information: An Analysis of the Processes Involved and the Products Generated in a Written Synthesis Task

    Science.gov (United States)

    Sole, Isabel; Miras, Mariana; Castells, Nuria; Espino, Sandra; Minguela, Marta

    2013-01-01

    The case study reported here explores the processes involved in producing a written synthesis of three history texts and their possible relation to the characteristics of the texts produced and the degree of comprehension achieved following the task. The processes carried out by 10 final-year compulsory education students (15 and 16 years old) to…

  4. Rho family GTP binding proteins are involved in the regulatory volume decrease process in NIH3T3 mouse fibroblasts

    DEFF Research Database (Denmark)

    Pedersen, Stine F; Beisner, Kristine H; Willumsen, Berthe M

    2002-01-01

    The role of Rho GTPases in the regulatory volume decrease (RVD) process following osmotic cell swelling is controversial and has so far only been investigated for the swelling-activated Cl- efflux. We investigated the involvement of RhoA in the RVD process in NIH3T3 mouse fibroblasts, using wild-...

  5. X inactivation counting and choice is a stochastic process : evidence for involvement of an X-linked activator

    NARCIS (Netherlands)

    Monkhorst, Kim; Jonkers, Iris; Rentmeester, Eveline; Grosveld, Frank; Gribnau, Joost

    2008-01-01

    Female mammalian cells achieve dosage compensation of X-encoded genes by X chromosome inactivation (XCI). This process is thought to involve X chromosome counting and choice. To explore how this process is initiated, we analyzed XCI in tetraploid XXXX, XXXY, and XXYY embryonic stem cells and found t

  6. Domain wall pinning on strain relaxation defects in FePt(001)/Pt thin films

    Energy Technology Data Exchange (ETDEWEB)

    Attane, J. P.; Samson, Y.; Marty, A.; Halley, D.; Beigne, C.

    2001-08-06

    Thin FePt (001) films, grown by molecular-beam epitaxy on Pt(001), exhibit a very large perpendicular magnetic anisotropy (K{sub u}=5 x 10{sup 6}Jm{sup -3}) and a 100% magnetic remanence in perpendicular field. The lattice misfit between FePt and Pt (1.5%) relaxes through the pileup of a/6 <112> partial dislocations along {l_brace}111{r_brace} planes, leading to the formation of microtwins. Atomic force microscopy images demonstrate that this process induces a spontaneous rectangular nanostructuration of the sample, while magnetic force microscopy shows that the microtwins act as pinning sites for the magnetic walls. This leads to square magnetic domains and explains the large coercivity associated with the domain wall propagation. {copyright} 2001 American Institute of Physics.

  7. Domain wall pinning on strain relaxation defects in FePt(001)/Pt thin films

    Science.gov (United States)

    Attané, J. P.; Samson, Y.; Marty, A.; Halley, D.; Beigné, C.

    2001-08-01

    Thin FePt (001) films, grown by molecular-beam epitaxy on Pt(001), exhibit a very large perpendicular magnetic anisotropy (Ku=5×106J m-3) and a 100% magnetic remanence in perpendicular field. The lattice misfit between FePt and Pt (1.5%) relaxes through the pileup of a/6 partial dislocations along {111} planes, leading to the formation of microtwins. Atomic force microscopy images demonstrate that this process induces a spontaneous rectangular nanostructuration of the sample, while magnetic force microscopy shows that the microtwins act as pinning sites for the magnetic walls. This leads to square magnetic domains and explains the large coercivity associated with the domain wall propagation.

  8. Nanospheres caped Pt(II and Pt (IV: synthesis and evaluation as antimicrobial and Antifungal Agent

    Directory of Open Access Journals (Sweden)

    Öğütçü Hatice

    2017-03-01

    Full Text Available Antimicrobial and antifungal polymers are gaining the attention of pharmaceutical makers and industrial design. Nanospheres-Polymers attached Platinum(II / (IV complexes have been synthesized to investigate antimicrobial activities. Firstly, nanospheres involving Schiff bases were synthesized from (aminomethyl polystyrene and four substitute salicylaldehyde (2-hydroxy benzaldehyde, 5-fluoro-2-hydroxy benzaldehyde, 5-kloro-2-hydroxy benzaldehyde, 5-bromo-2-hydroxy benzaldehyde. Secondly, polymers attached Platinum(II / (IV complexes have been prepared by means of template method. The IR spectra show that the ligands act in a monovalent bidentate fashion all nanospheres involving Schiff bases. Square-planar and octahedral structures are proposed for Pt(II and Pt(IV, respectively. All these substances have been examined for antibacterial activity against pathogenic strains, and antifungal activity. In particular, Pt(IV complexes were more potent bactericides than all of the synthesized substances.

  9. Active pharmaceutical ingredient (API) production involving continuous processes--a process system engineering (PSE)-assisted design framework.

    Science.gov (United States)

    Cervera-Padrell, Albert E; Skovby, Tommy; Kiil, Søren; Gani, Rafiqul; Gernaey, Krist V

    2012-10-01

    A systematic framework is proposed for the design of continuous pharmaceutical manufacturing processes. Specifically, the design framework focuses on organic chemistry based, active pharmaceutical ingredient (API) synthetic processes, but could potentially be extended to biocatalytic and fermentation-based products. The method exploits the synergic combination of continuous flow technologies (e.g., microfluidic techniques) and process systems engineering (PSE) methods and tools for faster process design and increased process understanding throughout the whole drug product and process development cycle. The design framework structures the many different and challenging design problems (e.g., solvent selection, reactor design, and design of separation and purification operations), driving the user from the initial drug discovery steps--where process knowledge is very limited--toward the detailed design and analysis. Examples from the literature of PSE methods and tools applied to pharmaceutical process design and novel pharmaceutical production technologies are provided along the text, assisting in the accumulation and interpretation of process knowledge. Different criteria are suggested for the selection of batch and continuous processes so that the whole design results in low capital and operational costs as well as low environmental footprint. The design framework has been applied to the retrofit of an existing batch-wise process used by H. Lundbeck A/S to produce an API: zuclopenthixol. Some of its batch operations were successfully converted into continuous mode, obtaining higher yields that allowed a significant simplification of the whole process. The material and environmental footprint of the process--evaluated through the process mass intensity index, that is, kg of material used per kg of product--was reduced to half of its initial value, with potential for further reduction. The case-study includes reaction steps typically used by the pharmaceutical

  10. Socialization Values and Parenting Practices as Predictors of Parental Involvement in Their Children's Educational Process

    NARCIS (Netherlands)

    Kikas, Eve; Tulviste, Tiia; Peets, Kätlin

    2014-01-01

    Research Findings: The purpose of this study was to examine associations between parental socialization values (including inconsistency in values), parenting practices, and parental involvement in their children's education. Altogether 242 Estonian mothers and fathers of first-grade children partici

  11. Socialization Values and Parenting Practices as Predictors of Parental Involvement in Their Children's Educational Process

    NARCIS (Netherlands)

    Kikas, Eve; Tulviste, Tiia; Peets, Kätlin

    2014-01-01

    Research Findings: The purpose of this study was to examine associations between parental socialization values (including inconsistency in values), parenting practices, and parental involvement in their children's education. Altogether 242 Estonian mothers and fathers of first-grade children

  12. Power relations and contrasting conceptions of evidence in patient-involvement processes used to inform health funding decisions in Australia.

    Science.gov (United States)

    Lopes, Edilene; Carter, Drew; Street, Jackie

    2015-06-01

    We collected and analysed views of key stakeholders on the processes used to involve patient organisations in health care funding decision making in Australia. We conducted 12 semi-structured interviews with patient organisation representatives and members of Advisory Committees that provide advice to the Australian Department of Health and employ Health Technology Assessment (HTA) as an evaluation framework. Using two theoretical frameworks, we analysed structural and contextual elements pertaining to the involvement processes. The findings reported in this article relate to interviewees' perspectives on contextual elements, analysed using a Foucauldian lens. These elements include: the perspectives of marginalised voices; the diversity of views on what ought to be considered valid evidence in a HTA setting; and the relationships between stakeholders, along with how these relationships impact on involvement processes and the outcomes of those processes. The findings demonstrate that the involvement processes currently used are deemed inadequate by both patient organisation representatives and Advisory Committee members, but for different reasons connected to how different stakeholders conceptualise evidence. Advisory Committee members viewed evidence as encompassing clinical outcomes and patient preferences, whereas patient organisation representatives tended to view evidence as encompassing aspects not directly related to a disease entity, such as the social and emotional aspects of patients' experiences in living with illness. Patient organisation representatives reported interacting with other stakeholders (especially industry) to increase the influence of their conception of evidence on decision making. The use of this strategy by interviewees illustrates how power struggles occur in government decision-making processes which involve both medical expertise and patients' accounts. Such struggles, and the power differentials they reflect, need to be considered

  13. Functionalized graphene-Pt composites for fuel cells and photoelectrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Diankov, Georgi; An, Jihwan; Park, Joonsuk; Goldhaber, David J. K.; Prinz, Friedrich B.

    2017-08-29

    A method of growing crystals on two-dimensional layered material is provided that includes reversibly hydrogenating a two-dimensional layered material, using a controlled radio-frequency hydrogen plasma, depositing Pt atoms on the reversibly hydrogenated two-dimensional layered material, using Atomic Layer Deposition (ALD), where the reversibly hydrogenated two-dimensional layered material promotes loss of methyl groups in an ALD Pt precursor, and forming Pt-O on the reversibly hydrogenated two-dimensional layered material, using combustion by O.sub.2, where the Pt-O is used for subsequent Pt half-cycles of the ALD process, where growth of Pt crystals occurs.

  14. Strategic Co-Location in a Hybrid Process Involving Desalination and Pressure Retarded Osmosis (PRO)

    OpenAIRE

    Krantz, William B.; Anthony G. Fane; Tzyy Haur Chong; Chuyang Y. Tang; Sim, Victor S.T.; Qianhong She

    2013-01-01

    This paper focuses on a Hybrid Process that uses feed salinity dilution and osmotic power recovery from Pressure Retarded Osmosis (PRO) to achieve higher overall water recovery. This reduces the energy consumption and capital costs of conventional seawater desalination and water reuse processes. The Hybrid Process increases the amount of water recovered from the current 66.7% for conventional seawater desalination and water reuse processes to a potential 80% through the use of reclaimed water...

  15. Syntheses, Structures, and Electrochemistry of the Defective ccp [Pt33(CO)38](2-) and the bcc [Pt40(CO)40](6-) Molecular Nanoclusters.

    Science.gov (United States)

    Cattabriga, Enrico; Ciabatti, Iacopo; Femoni, Cristina; Funaioli, Tiziana; Iapalucci, Maria Carmela; Zacchini, Stefano

    2016-06-20

    The molecular [Pt33(CO)38](2-) nanocluster was obtained from the thermal decomposition of Na2[Pt15(CO)30] in methanol. The reaction of [Pt19(CO)22](4-) with acids (1-2 equiv) affords the unstable [Pt19(CO)22](3-) trianion, which evolves with time leading eventually to the [Pt40(CO)40](6-) hexa-anion. The total structures of both nanoclusters were determined via single-crystal X-ray diffraction. [Pt33(CO)38](2-) displays a defective ccp Pt33 core and shows that localized deformations occur in correspondence of atomic defects to "repair" them. In contrast, [Pt40(CO)40](6-) shows a bcc Pt40 core and represents the largest Pt cluster with a body-centered structure. The rich electrochemistry of the two high-nuclearity platinum carbonyl clusters was studied by cyclic voltammetry and electrochemical in situ Fourier transform infrared spectroscopy. The redox changes of [Pt33(CO)38](2-) show features of chemical reversibility and electrochemical quasi-reversibility, and the vibrational spectra in the CO stretching region of the nine redox forms of the cluster [Pt33(CO)38](n) (n = 0 to -4, -6 to -9) are reported. Almost all the redox processes exhibited by [Pt40(CO)40](6-) are chemically and electrochemically reversible, and the eight oxidation states of [Pt40(CO)40] from -4 to -11 were spectroscopically characterized. The effect of the more regular bcc Pt-carbonyl cluster structure of [Pt40(CO)40](6-) with respect to that of the defective ccp Pt33 core on the redox behavior is discussed.

  16. The theory of active involvement: processes underlying interventions that engage adolescents in message planning and/or production.

    Science.gov (United States)

    Greene, Kathryn

    2013-01-01

    Adolescence is a time of increased risk taking, and recent intervention strategies have included adolescents planning or producing antirisk messages for their peers. Although these projects may generate enthusiasm, we know little about message planning or production as a strategy for changing adolescent decision-making and behavior. This article articulates the Theory of Active Involvement (TAI) to describe and explain the processes through which these active involvement interventions influence adolescents. TAI is based on social cognitive theory's notion of self-regulation and examines multiple perspective taking and activating the self-reflection processes. The theory specifically describes the process of cognitive changes experienced by participants in active involvement interventions. The sequence is conceptualized as starting when engagement with the intervention (arousal and involvement) produces skill and knowledge gains (immediate outcomes) that lead to reflection (perceived discrepancy) and then other cognitions (expectancies, norms, intentions), with the ultimate outcome being behavior change. Engaging the target audience in a process of self-reflection is conceptualized as the crucial ingredient for meaningful and sustainable change in cognitions and behavior. This article provides valuable insight into how active involvement strategies function and how to best design these interventions, particularly those targeting adolescents.

  17. Tailoring nucleation and growth conditions for narrow compositional distributions in colloidal synthesized FePt nanoparticles

    Science.gov (United States)

    Srivastava, Chandan; Nikles, David E.; Thompson, Gregory B.

    2008-11-01

    To eliminate compositional and size variabilities between individual binary nanoparticles, it is essential to control the mechanistic steps involved in nanoparticle synthesis. A common method for synthesizing FePt nanoparticles involves the simultaneous decomposition and reduction in iron and platinum precursors, respectively. This simultaneous nucleation and growth method yields wide composition and size distributions. This paper describes and experimentally validates a methodology needed to tighten composition and size distributions for this process. By engineering the surfactant chemistry with tertiary phosphines to tightly bind the iron atoms in the iron precursor, uniform platinum rich seeds form during the initial stages of the synthesis. A thermodynamically preferred heterogeneous nucleation of iron atoms into these uniform platinum seeds in the subsequent stages produces a final dispersion with uniform particle-to-particle compositions. The paper addresses the understanding for optimizing the nucleation and growth sequences for compositional control in FePt nanoparticles.

  18. Bacterial populations and processes involved in acetate and propionate consumption in anoxic brackish sediment

    NARCIS (Netherlands)

    Boschker, H.T.S.; De Graaf, W.; Köster, M.; Meyer-Reil, L.A.; Cappenberg, T.E.

    2001-01-01

    Bacterial populations and pathways involved in acetate and propionate consumption were studied in anoxic brackish sediment from the Grosser Jasmunder Bodden, German Baltic Sea. Uptake of acetate and propionate from the porewater was studied using stable carbon isotope-labeled compounds. Labeled acet

  19. Software Quality Perceptions of Stakeholders Involved in the Software Development Process

    Science.gov (United States)

    Padmanabhan, Priya

    2013-01-01

    Software quality is one of the primary determinants of project management success. Stakeholders involved in software development widely agree that quality is important (Barney and Wohlin 2009). However, they may differ on what constitutes software quality, and which of its attributes are more important than others. Although, software quality…

  20. Acculturation and Latino Family Processes: How Cultural Involvement, Biculturalism, and Acculturation Gaps Influence Family Dynamics

    Science.gov (United States)

    Smokowski, Paul R.; Rose, Roderick; Bacallao, Martica L.

    2008-01-01

    This study investigated how adolescent and parent acculturation (culture-of-origin and U.S. cultural involvement, biculturalism, acculturation conflicts, and parent-adolescent acculturation gaps) influenced family dynamics (family cohesion, adaptability, familism, and parent-adolescent conflict) in a sample of 402 Latino families from North…

  1. Software Quality Perceptions of Stakeholders Involved in the Software Development Process

    Science.gov (United States)

    Padmanabhan, Priya

    2013-01-01

    Software quality is one of the primary determinants of project management success. Stakeholders involved in software development widely agree that quality is important (Barney and Wohlin 2009). However, they may differ on what constitutes software quality, and which of its attributes are more important than others. Although, software quality…

  2. Could early septal involvement in the remodeling process be related to the advance hypertensive heart disease?

    Directory of Open Access Journals (Sweden)

    Fatih Yalçin

    2015-06-01

    Conclusions: LV diastolic dysfunction becomes more severe in septal wall than lateral wall in hypertensive LVH. Septal myocardial performance is more dominantly affected by hypertension possibly due to earlier septal involvement in disease course. Septal MPI is correlated moderately with septal wall thickness.

  3. Enhancing Home Involvement to Address Barriers to Learning: A Collaborative Process. A Center Report

    Science.gov (United States)

    Center for Mental Health in Schools at UCLA, 2011

    2011-01-01

    For schools to significantly enhance home involvement will require (1) broadening the focus beyond thinking only in terms of parents and (2) enhancing the range of ways in which schools connect with primary caretakers. Particular attention must be given to outreaching to those who are reluctant to engage with the school, especially if they have a…

  4. Involving Immigrant Parents of Students with Disabilities in the Educational Process.

    Science.gov (United States)

    Al-Hassan, Suha; Gardner, Ralph, III

    2002-01-01

    This article discusses the barriers that limit school participation by immigrant parents of students with disabilities, including language differences, lack of information, negative educational experiences, unfamiliarity with the U.S. educational practices, cultural differences, and differing views regarding involvement in schools. Strategies are…

  5. No Longer a Teacher Monologue--Involving EFL Writing Learners in Teachers' Assessment and Feedback Processes

    Science.gov (United States)

    Huang, Shu-Chen

    2016-01-01

    This paper reports the design of learning-oriented formative assessments in an EFL writing course that involved learners in regularly responding to teacher feedback. Following major assessment and feedback frameworks developed recently, these formative assessments were explicated in three aspects: the scheduling of learning and assessment…

  6. Using Dual-Task Methodology to Dissociate Automatic from Nonautomatic Processes Involved in Artificial Grammar Learning

    Science.gov (United States)

    Hendricks, Michelle A.; Conway, Christopher M.; Kellogg, Ronald T.

    2013-01-01

    Previous studies have suggested that both automatic and intentional processes contribute to the learning of grammar and fragment knowledge in artificial grammar learning (AGL) tasks. To explore the relative contribution of automatic and intentional processes to knowledge gained in AGL, we utilized dual-task methodology to dissociate automatic and…

  7. Microwave-assisted synthesis of high-loading, highly dispersed Pt/carbon aerogel catalyst for direct methanol fuel cell

    Indian Academy of Sciences (India)

    Zhijun Guo; Hong Zhu; Xinwei Zhang; Fanghui Wang; Yubao Guo; Yongsheng Wei

    2011-06-01

    A Pt supported on carbon aerogel catalyst has been synthesized by the microwave-assisted polyol process. The Pt supported on carbon aerogel catalyst was characterized by high resolution transmission electron microscopy and X-ray diffraction. The results show a uniform dispersion of spherical Pt nanoparticles 2.5–3.0 nm in diameter. Cyclic voltammetry and chronoamperometry were used to evaluate the electrocatalytic activity of the Pt/carbon aerogel catalyst for methanol oxidation at room temperature. The Pt/carbon aerogel catalyst shows higher electrochemical catalytic activity and stability for methanol oxidation than a commercial Pt/C catalyst of the same Pt loading.

  8. Oxygen Reduction Reaction on Pt Overlayers Deposited onto a Gold Film: Ligand, Strain, and Ensemble Effect

    DEFF Research Database (Denmark)

    Deng, Yu-Jia; Tripkovic, Vladimir; Rossmeisl, Jan;

    2016-01-01

    We study the oxygen reduction reaction (ORR), the catalytic process occurring at the cathode in fuel cells, on Pt layers prepared by electrodeposition onto an Au substrate. Using a nominal Pt layer by layer deposition method previously proposed, imperfect layers of Pt on Au are obtained. The ORR ...

  9. Child Involvement, Alliance, and Therapist Flexibility: Process Variables in Cognitive-Behavioural Therapy for Anxiety Disorders in Childhood

    Science.gov (United States)

    Hudson, Jennifer L.; Kendall, Philip C.; Chu, Brian C.; Gosch, Elizabeth; Martin, Erin; Taylor, Alan; Knight, Ashleigh

    2013-01-01

    Background This study examined the relations between treatment process variables and child anxiety outcomes. Method Independent raters watched/listened to taped therapy sessions of 151 anxiety-disordered (6 -14 yr-old; M = 10.71) children (43% boys) and assessed process variables (child alliance, therapist alliance, child involvement, therapist flexibility and therapist functionality) within a manual-based cognitive-behavioral treatment. Latent growth modelling examined three latent variables (intercept, slope, and quadratic) for each process variable. Child age, gender, family income and ethnicity were examined as potential antecedents. Outcome was analyzed using factorially derived clinician, mother, father, child and teacher scores from questionnaire and structured diagnostic interviews at pretreatment, posttreatment and 12-month follow-up. Results Latent growth models demonstrated a concave quadratic curve for child involvement and therapist flexibility over time. A predominantly linear, downward slope was observed for alliance, and functional flexibility remained consistent over time. Increased alliance, child involvement and therapist flexibility showed some albeit inconsistent, associations with positive treatment outcome. Conclusion Findings support the notion that maintaining the initial high level of alliance or involvement is important for clinical improvement. There is some support that progressively increasing alliance/involvement also positively impacts on treatment outcome. These findings were not consistent across outcome measurement points or reporters. PMID:24246476

  10. Strategic Co-Location in a Hybrid Process Involving Desalination and Pressure Retarded Osmosis (PRO

    Directory of Open Access Journals (Sweden)

    William B. Krantz

    2013-07-01

    Full Text Available This paper focuses on a Hybrid Process that uses feed salinity dilution and osmotic power recovery from Pressure Retarded Osmosis (PRO to achieve higher overall water recovery. This reduces the energy consumption and capital costs of conventional seawater desalination and water reuse processes. The Hybrid Process increases the amount of water recovered from the current 66.7% for conventional seawater desalination and water reuse processes to a potential 80% through the use of reclaimed water brine as an impaired water source. A reduction of up to 23% in energy consumption is projected via the Hybrid Process. The attractiveness is amplified by potential capital cost savings ranging from 8.7%–20% compared to conventional designs of seawater desalination plants. A decision matrix in the form of a customizable scorecard is introduced for evaluating a Hybrid Process based on the importance of land space, capital costs, energy consumption and membrane fouling. This study provides a new perspective, looking at processes not as individual systems but as a whole utilizing strategic co-location to unlock the synergies available in the water-energy nexus for more sustainable desalination.

  11. Strategic Co-Location in a Hybrid Process Involving Desalination and Pressure Retarded Osmosis (PRO).

    Science.gov (United States)

    Sim, Victor S T; She, Qianhong; Chong, Tzyy Haur; Tang, Chuyang Y; Fane, Anthony G; Krantz, William B

    2013-07-04

    This paper focuses on a Hybrid Process that uses feed salinity dilution and osmotic power recovery from Pressure Retarded Osmosis (PRO) to achieve higher overall water recovery. This reduces the energy consumption and capital costs of conventional seawater desalination and water reuse processes. The Hybrid Process increases the amount of water recovered from the current 66.7% for conventional seawater desalination and water reuse processes to a potential 80% through the use of reclaimed water brine as an impaired water source. A reduction of up to 23% in energy consumption is projected via the Hybrid Process. The attractiveness is amplified by potential capital cost savings ranging from 8.7%-20% compared to conventional designs of seawater desalination plants. A decision matrix in the form of a customizable scorecard is introduced for evaluating a Hybrid Process based on the importance of land space, capital costs, energy consumption and membrane fouling. This study provides a new perspective, looking at processes not as individual systems but as a whole utilizing strategic co-location to unlock the synergies available in the water-energy nexus for more sustainable desalination.

  12. Monte carlo simulations of segregation in Pt-Re catalyst nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guofeng; Van Hove, M.A.; Ross, P.N.; Baskes, M.I.

    2004-04-01

    We have investigated the segregation of Pt atoms to the surfaces of Pt-Re nanoparticles using the Monte Carlo method and Modified Embedded Atom Method potentials that we have developed for Pt-Re alloys. The Pt75Re25 nanoparticles (containing from 586 to 4033 atoms) are assumed to have disordered fcc configurations and cubo-octahedral shapes (terminated by {l_brace}111{r_brace} and {l_brace}100{r_brace} facets), while the Pt50Re50 and Pt25Re75 nanoparticles (containing from 587 to 4061 atoms) are assumed to have disordered hcp configurations and truncated hexagonal bipyramidal shapes (terminated by {l_brace}0001{r_brace} and {l_brace}101 {bar 1}{r_brace} facets). We predict that due to the segregation process the equilibrium Pt-Re nanoparticles would achieve a core-shell structure, with a Pt-enriched shell surrounding a Pt-deficient core. For fcc cubo-octahedral Pt75Re25 nanoparticles, the shells consist of almost 100 at. percent of Pt atoms. Even in the shells of hcp truncated hexagonal bipyramidal Pt50Re50 nanoparticles, the concentrations of Pt atoms exceed 85 at. percent (35 at. percent higher than the overall concentration of Pt atoms in these nanoparticles). Most prominently, all Pt atoms will segregate to the surfaces in the hcp truncated hexagonal bipyramidal Pt25Re75 nanoparticles containing less than 1000 atoms. We also find that the Pt atoms segregate preferentially to the vertex sites, less to edge sites, and least to facet sites on the shell of Pt-Re nanoparticles.

  13. Titan's GOO-Sphere: Glacial, Permafrost, Evaporite, and Other Familiar Processes Involving Exotic Materials

    Science.gov (United States)

    Kargel, J. S.; Furfaro, R.; Hays, C. C.; Lopes, R. M. C.; Lunine, J. I.; Mitchell, K. L.; Wall, S. D.; Cassini RADAR Team

    2007-03-01

    A new Geologic Operating Organon (GOO) for Titan is based on the cryogenic activity of many hydrocarbon and organic substances. This model derives insight from volcanic, fluvial, lacustrine, permafrost, and glacial processes on Earth and beyond.

  14. The rehabilitation process of children with motor disabilities in the Dutch therapeutic toddler class: main phases and parent involvement.

    NARCIS (Netherlands)

    Hendriks, A.H.C.; Moor, J.M.H. de; Savelberg, M.M.H.W.; Oud, J.H.L.

    2001-01-01

    This study describes the implementation of the main phases of the rehabilitation process of children with motor disabilities who visit Dutch therapeutic toddler classes. Parent involvement, as well as parents' and professionals' satisfaction were also investigated. It was found that in about half of

  15. The rehabilitation process of children with motor disabilities in the Dutch therapeutic toddler class: main phases and parent involvement.

    NARCIS (Netherlands)

    Hendriks, A.H.C.; Moor, J.M.H. de; Savelberg, M.M.H.W.; Oud, J.H.L.

    2001-01-01

    This study describes the implementation of the main phases of the rehabilitation process of children with motor disabilities who visit Dutch therapeutic toddler classes. Parent involvement, as well as parents' and professionals' satisfaction were also investigated. It was found that in about half of

  16. Early Childhood Spaces: Involving Young Children and Practitioners in the Design Process. Working Papers in Early Childhood Development, No. 45

    Science.gov (United States)

    Clark, Alison

    2007-01-01

    This working paper explores the methodology and initial issues raised in seeking to involve young children in the design process. It reports a study concerned with how young children can play an active role in the designing and developing of children's spaces. The focus is on children under 6 years old in early childhood provision. (Contains 2…

  17. Application of Ict and Rubrics to the Assessment Process where Professional Judgement Is Involved: The Features of an Emarking Tool

    Science.gov (United States)

    Campbell, Alistair

    2005-01-01

    This paper describes a new ICT assessment tool that reduces multihandling of marks, comments and scores specifically where professional judgement is involved. Whereas previous ICT applications in most fields of education have focused on student learning, this tool focuses on the lecturer task of the assessment process. Unlike many ICT based…

  18. [Facilitating Processes of Disintegration instead of Occupational Reintegration: A Qualitative Study on Employer-Involvement in Rehabilitation].

    Science.gov (United States)

    Schwarz, Betje; Specht, Timo; Bethge, Matthias

    2017-06-30

    Purpose To explore the patient's perspective on the involvement of employers into rehabilitation. Methods 8 participants of a work-related medical rehabilitation were interviewed by telephone 4 weeks after discharge. Qualitative content analysis was used to analyze generated data. Results Beside a poor employer-involvement, the interviews revealed that the process of returning to work was characterized and hampered by unused measures of supporting vocational reintegration during rehabilitation, intersection problems in the health care and social security system, and a strategy of waiting by all involved actors. Conclusion Beside an improved employer-involvement, systematic intersection management and full usage of existing measures are demanded to support vocational reintegration. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Pt, PtCo and PtNi electrocatalysts prepared by mechanical alloying for the oxygen reduction reaction in 0.5 M H{sub 2}SO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Contreras, M.A. [Instituto Nacional de Investigaciones Nucleares, Depto. de Quimica, Apdo. Postal 18-1027 Col. Escandon, C.P.11801 Mexico D.F. (Mexico); Instituto Politecnico Nacional, Depto. de Ing. Metalurgica, 07300 Mexico D.F. (Mexico); Fernandez-Valverde, S.M. [Instituto Nacional de Investigaciones Nucleares, Depto. de Quimica, Apdo. Postal 18-1027 Col. Escandon, C.P.11801 Mexico D.F. (Mexico); Vargas-Garcia, J.R. [Instituto Politecnico Nacional, Depto. de Ing. Metalurgica, 07300 Mexico D.F. (Mexico); Cortes-Jacome, M.A.; Toledo-Antonio, J.A.; Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas 152, Mexico, D.F.,0 7730 (Mexico)

    2008-11-15

    Electrocatalysts of Pt, PtCo and PtNi powders for the oxygen reduction reaction (ORR) were processed by Mechanical Alloying. Physical characterization was made by X-ray diffraction, scanning electron microscopy and scanning transmission electron microscopy. It was found that milled powders formed agglomerates in the range of 0.2-20 {mu}m formed by nanometric size crystallites. The synthesized powders were alloys of PtFe, PtCoFe and PtNiFe due to iron incorporation during the milling process. The binding energies of Pt in the alloys were determined by XPS. Polarization curves were obtained by Rotating Disk Electrode technique in 0.5 M H{sub 2}SO{sub 4} to determine the electrocatalytic activity of the mechanically alloyed powders. Tafel curves were plotted and kinetic parameters for the ORR were calculated. The PtFe alloy showed the highest electrocatalytic activity for the ORR. However, the lowest overpotential was found for the PtCoFe alloy and it also showed a higher current exchange density. A linear relationship was found between the Pt-binding energy in the alloys and the overpotential at the same current density independent of the Pt alloy composition. (author)

  20. Neural networks involved in adolescent reward processing: An activation likelihood estimation meta-analysis of functional neuroimaging studies.

    Science.gov (United States)

    Silverman, Merav H; Jedd, Kelly; Luciana, Monica

    2015-11-15

    Behavioral responses to, and the neural processing of, rewards change dramatically during adolescence and may contribute to observed increases in risk-taking during this developmental period. Functional MRI (fMRI) studies suggest differences between adolescents and adults in neural activation during reward processing, but findings are contradictory, and effects have been found in non-predicted directions. The current study uses an activation likelihood estimation (ALE) approach for quantitative meta-analysis of functional neuroimaging studies to: (1) confirm the network of brain regions involved in adolescents' reward processing, (2) identify regions involved in specific stages (anticipation, outcome) and valence (positive, negative) of reward processing, and (3) identify differences in activation likelihood between adolescent and adult reward-related brain activation. Results reveal a subcortical network of brain regions involved in adolescent reward processing similar to that found in adults with major hubs including the ventral and dorsal striatum, insula, and posterior cingulate cortex (PCC). Contrast analyses find that adolescents exhibit greater likelihood of activation in the insula while processing anticipation relative to outcome and greater likelihood of activation in the putamen and amygdala during outcome relative to anticipation. While processing positive compared to negative valence, adolescents show increased likelihood for activation in the posterior cingulate cortex (PCC) and ventral striatum. Contrasting adolescent reward processing with the existing ALE of adult reward processing reveals increased likelihood for activation in limbic, frontolimbic, and striatal regions in adolescents compared with adults. Unlike adolescents, adults also activate executive control regions of the frontal and parietal lobes. These findings support hypothesized elevations in motivated activity during adolescence.

  1. Pt- and FePt- nanoparticles on the basis of emulsion techniques

    Energy Technology Data Exchange (ETDEWEB)

    Manzke, Achim; Wiedemann, Stefan; Enderle, Fabian; Plettl, Alfred; Ziemann, Paul [Institut fuer Festkoerperphysik, Universitaet Ulm (Germany); Schreiber, Eyk; Ziener, Ulrich [Institut fuer Organische Chemie III, Universitaet Ulm (Germany); Vogel, Nicolas; Landfester, Katharina [MPI fuer Polymerforschung, Mainz (Germany); Biskupek, Johannes; Kaiser, Ute [Materialwissenschaftliche Elektronenmikroskopie, Universitaet Ulm (Germany)

    2010-07-01

    Metal-precursor loaded colloidal polystyrene (PS) particles in aqueous solution are produced by an emulsion and miniemulsion technique, respectively. We report on colloids loaded with Pt- as well as with Fe- and Pt-complexes. After deposition of a hexagonally ordered monolayer of PS spheres on top of a silicon substrate, optimized plasma and temper sequences are applied to obtain metallic nanoparticles which still exhibit the original lateral order. The metal content within a colloid defines the size of the final particle, which could be varied between 6 and 14 nm, so far. The interparticle distance is determined by the diameter of the starting PS-particles and was varied between 80 and 250 nm. Different process steps are investigated by HRSEM, HRTEM and XPS giving insight in the plasma- and annealing process and demonstrating e.g. the crystalline structure of the Pt- nanoparticles.

  2. Study of Hydrogen Adsorption on Pt/WO3-ZrO2 through Pt Sites

    Institute of Scientific and Technical Information of China (English)

    Sugeng Triwahyono; Aishah Abdul Jalil; Hideshi Hattori

    2007-01-01

    The rate determining step and the energy barrier involved in hydrogen adsorption on Pt/WO3ZrO2 were studied based on the assumption that the hydrogen adsorption occurs only through Pt sites.The rate of hydrogen adsorption on Pt/WO3-ZrO2 Was measured in the adsorption temperature range of 323-573 K and an initial hydrogen pressure of 50 Torr.The rates of hydrogen uptake were very high for the initial few minutes and the adsorption continued for more than 5 h below 523 K.The hydrogen uptake far exceeded the H/Pt ratio of unity for all adsorption temperatures,indicating that the adsorption of hydrogen involved the dissociative adsorption of hydrogen on Pt sites to form hydrogen atoms.the spillover of hydrogen atoms onto the surface of the WO3-ZrO2 catalyst.the diffusion of spiltover hydrogen atom over the surface of the WO3-ZrO2 catalyst,and the formation of protonic acid site originated from hydrogen atom by releasing an electron in which the electron may react with a second hydrogen atom to form a hydride near the Lewis acid site.The rate determining step was the spillover with the activation energy of 12.3 kJ/mol.The rate of hydrogen adsorption cannot be expressed by the rate equation based on the assumption that the rate determining step is the surface diffusion.The activity of Pt/WO3-ZrO2 Was examined on n-heptane isomerization in which the increase of hydrogen partial pressure provided positive-effect on the conversion of n-heptane and negative-effect on the selectivity towards iso-heptane.

  3. The variability of processes involved in transgene dispersal - case studies from Brassica and related genera

    DEFF Research Database (Denmark)

    Bagger Jørgensen, Rikke; Hauser, Thure Pavlo; D'Hertefeldt, T.

    2009-01-01

    Background, aim, and scope We strive to predict consequences of genetically modified plants (GMPs) being cultivated openly in the environment, as human and animal health, biodiversity, agricultural practise and farmers’ economy could be affected. Therefore, it is unfortunate that the risk...... is a valuable tool in identifying key factors in the gene-flow process for which more knowledge is needed, and identifying parameters and processes which are relatively insensitive to change and therefore require less attention in future collections of data. But the interdependence between models...

  4. Processes involved in assisted reproduction technologies significantly increase sperm DNA fragmentation and phosphatidylserine translocation.

    Science.gov (United States)

    Balasuriya, A; Serhal, P; Doshi, A; Harper, J C

    2014-03-01

    Sperm preparation techniques in assisted reproduction technologies (ART) are potential generators of exogenous stresses that cause additional DNA damage. DNA fragmentation tests, such as the sperm chromatin structure assay, involve freezing sperm samples in the absence of cryoprotectant. Thermal, oxidative stress (OS) and freezing are detrimental to sperm DNA fragmentation and phosphatidylserine (PS) translocation. The primary aim of this study was to subject mature sperm to environmental insults that normally occur during ART. We tested the hypotheses that OS, thermal stress and freeze-thawing caused sperm nuclear and membrane damage and that a positive correlation exists between PS translocation and DNA fragmentation. Sperm DNA integrity deteriorates in semen samples from men with advancing age and a sperm concentration of DNA fragmentation at 37 °C after merely 1 h is important clinically as semen liquefaction and short-term sperm storage in an ART cycle involve incubating samples at this temperature. Freezing without a cryoprotectant significantly increases the level of sperm nuclear damage, so it is important not to freeze neat semen prior to DNA fragmentation testing. This study highlights the importance of minimising the production of exogenous stresses during sperm preparation in ART. © 2012 Blackwell Verlag GmbH.

  5. Effects of seasonal temperature variation on nitrification, anammox process, and bacteria involved in a pilot-scale constructed wetland.

    Science.gov (United States)

    Wang, Ling; Li, Tian

    2015-03-01

    Effects of seasonal temperature (especially low temperature) variation on nitrogen removal process and bacteria involved in an experimental domestic wastewater treatment wetland were investigated in this study. Three different functional groups of bacteria, namely anammox bacteria, ammonia-oxidizing bacteria (AOB), and Nitrospira sp., were involved. Anammox process was seriously inhibited with mean temperature lower than 15 °C. However, obvious adaptation of anammox bacteria also appeared after a long time operation under low temperatures. Contrary to anammox bacteria, AOB were more abundant in winter than in summer. Nitrospira sp. was the least prevalent and showed the lowest level of variation. Distinct nitrate accumulation observed under winter temperatures was likely due to inhibition of anammox process, comparative advantage of Nitrospira sp. in winter, and the presence of cold-tolerant AOB species.

  6. Brain regions involved in processing facial identity and expression are differentially selective for surface and edge information.

    Science.gov (United States)

    Harris, Richard J; Young, Andrew W; Andrews, Timothy J

    2014-08-15

    Although different brain regions are widely considered to be involved in the recognition of facial identity and expression, it remains unclear how these regions process different properties of the visual image. Here, we ask how surface-based reflectance information and edge-based shape cues contribute to the perception and neural representation of facial identity and expression. Contrast-reversal was used to generate images in which normal contrast relationships across the surface of the image were disrupted, but edge information was preserved. In a behavioural experiment, contrast-reversal significantly attenuated judgements of facial identity, but only had a marginal effect on judgements of expression. An fMR-adaptation paradigm was then used to ask how brain regions involved in the processing of identity and expression responded to blocks comprising all normal, all contrast-reversed, or a mixture of normal and contrast-reversed faces. Adaptation in the posterior superior temporal sulcus--a region directly linked with processing facial expression--was relatively unaffected by mixing normal with contrast-reversed faces. In contrast, the response of the fusiform face area--a region linked with processing facial identity--was significantly affected by contrast-reversal. These results offer a new perspective on the reasons underlying the neural segregation of facial identity and expression in which brain regions involved in processing invariant aspects of faces, such as identity, are very sensitive to surface-based cues, whereas regions involved in processing changes in faces, such as expression, are relatively dependent on edge-based cues.

  7. Age-Related Changes in Duration Reproduction: Involvement of Working Memory Processes

    Science.gov (United States)

    Baudouin, Alexia; Vanneste, Sandrine; Pouthas, Viviane; Isingrini, Michel

    2006-01-01

    The aim of the present research was to study age-related changes in duration reproduction by differentiating the working memory processes underlying this time estimation task. We compared performances of young and elderly adults in a duration reproduction task performed in simple and concurrent task conditions. Participants were also administered…

  8. A Study of User Involvement in the Military Construction Program Process.

    Science.gov (United States)

    1986-09-01

    sion change). B. Incomplete requirements during programming . C . Poorly defined requirements. D. Other *. E. There was no change in user...requirements during the MCP process. 30. Were you the responsible individual during the programming and design phase? A. Yes B. Only during programming C . Only

  9. Data, analysis and modeling of physical properties for process designof systems involving lipids

    DEFF Research Database (Denmark)

    Cunico, Larissa; Ceriani, Roberta; Sarup, Bent

    2013-01-01

    Pure component and mixture properties are necessary for synthesis, design, and analysis of processes forthe production of edible oils, fats, biodiesel, and other lipids. The lack of measured data for these systemsmakes it necessary to develop reliable predictive models based on limited data. We...

  10. Fantasy Activity and the Televiewing Event: Considerations for an Information Processing Construct of Involvement.

    Science.gov (United States)

    Lindlof, Thomas R.

    The similarities between television viewing and fantasy activity (daydreaming, reverie, mind-wandering, internal dialogue) more than warrant the building of a theoretical construct, especially in the context of recent empirical research on television viewing consequences. A construct of the television viewing process, based on cognitive theories…

  11. Parental Involvement in the Habilitation Process Following Children's Cochlear Implantation: An Action Theory Perspective

    Science.gov (United States)

    Zaidman-Zait, Anat; Young, Richard A.

    2008-01-01

    Action theory and the qualitative action-project method are used in this study to address and illustrate the complexity of parenting children who have received cochlear implants (CIs) as well as the intentionality of parents engaged in that process. "Action" refers to individual and joint goal-directed and intentional behaviors. Action theory has…

  12. Involvement of O-glycosylation defining oncofetal fibronectin in epithelial-mesenchymal transition process

    DEFF Research Database (Denmark)

    Freire-de-Lima, Leonardo; Gelfenbeyn, Kirill; Ding, Yao

    2011-01-01

    The process termed "epithelial-mesenchymal transition" (EMT) was originally discovered in ontogenic development, and has been shown to be one of the key steps in tumor cell progression and metastasis. Recently, we showed that the expression of some glycosphingolipids (GSLs) is down-regulated duri...

  13. Parent Involvement in the Special Education Eligibility Process: Implementation of Legal Mandates and Best Practices

    Science.gov (United States)

    McEvoy, Cathleen K.

    2013-01-01

    School psychologists throughout New York State were surveyed regarding their schools' policies to include parents in the special education eligibility process related to legal mandates and best practices. Differences were found in the implementation of legal mandates compared to implementation of best practices. Location differences were…

  14. GWAS for executive function and processing speed suggests involvement of the CADM2 gene

    NARCIS (Netherlands)

    Ibrahim-Verbaas, C. A.; Bressler, J.; Debette, S.; Schuur, M.; Smith, A. V.; Bis, J. C.; Davies, G.; Trompet, S.; Smith, J. A.; Wolf, C.; Chibnik, L. B.; Liu, Y.; Vitart, V.; Kirin, M.; Petrovic, K.; Polasek, O.; Zgaga, L.; Fawns-Ritchie, C.; Hoffmann, P.; Karjalainen, J.; Lahti, J.; Llewellyn, D. J.; Schmidt, C.O.; Mather, K. A.; Chouraki, V.; Sun, Q.; Resnick, S. M.; Rose, L. M.; Oldmeadow, C.; Stewart, M.; Smith, B.H.; Gudnason, V.; Yang, Q.; Mirza, S. S.; Jukema, J. W.; Dejager, P. L.; Harris, T. B.; Liewald, D. C.; Amin, N.; Coker, L. H.; Stegle, O.; Lopez, O. L.; Schmidt, R.; Teumer, A.; Ford, I.; Karbalai, N.; Becker, J. T.; Jonsdottir, M. K.; Au, R.; Fehrmann, R. S. N.; Herms, S.; Nalls, M.; Zhao, Wei; Turner, S. T.; Yaffe, K.; Lohman, K.; van Swieten, J. C.; Kardia, S. L. R.; Knopman, D. S.; Meeks, W. M.; Heiss, G.; Holliday, E. G.; Schofield, P. W.; Tanaka, T.; Stott, D. J.; Wang, J.; Ridker, P.; Gow, A. J.; Pattie, A.; Starr, J. M.; Hocking, L. J.; Armstrong, N. J.; McLachlan, S.; Shulman, J. M.; Pilling, L. C.; Eiriksdottir, G.; Scott, R. J.; Kochan, N. A.; Palotie, A.; Hsieh, Y-C; Eriksson, J. G.; Penman, A.; Gottesman, R. F.; Oostra, B. A.; Yu, L.; DeStefano, A. L.; Beiser, A.; Garcia, M.; Rotter, J. i; Noethen, M. M.; Hofman, A.; Slagboom, P. E.; Westendorp, R. G. J.; Buckley, B. M.; Wolf, P. A.; Uitterlinden, A. G.; Psaty, B. M.; Grabe, H. J.; Bandinelli, S.; Chasman, D. I.; Grodstein, F.; Roikkonen, K.; Lambert, J-C; Porteous, D. J.; Price, J. F.; Sachdev, P. S.; Ferrucci, L.; Attia, J. R.; Rudan, I.; Hayward, C.; Wright, A. F.; Wilson, James F.; Cichon, S.; Franke, L.; Schmidt, H.; Ding, J.; de Craen, A. J. M.; Fornage, M.; Bennett, D. A.; Deary, I. J.; Ikram, M. A.; Launer, L. J.; Fitzpatrick, A. L.; Seshadri, S.; van Duijn, C. M.; Mosley, T. H.

    2016-01-01

    To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Resea

  15. GWAS for executive function and processing speed suggests involvement of the CADM2 gene

    NARCIS (Netherlands)

    C.A. Ibrahim-Verbaas (Carla); J. Bressler; S. Debette (Stéphanie); M. Schuur (Maaike); A.V. Smith; J.C. Bis (Joshua); G. Davies (Gail); S. Trompet (Stella); J.A. Smith; A. Björnsson (Asgeir); L.B. Chibnik (Lori); Y. Liu; V. Vitart (Veronique); M. Kirin (Mirna); K. Petrovic (Katja); O. Polasek (Ozren); L. Zgaga (Lina); C. Fawns-Ritchie; P. Hoffmann (Per); J. Karjalainen (Juha); J. Lahti; D.J. Llewellyn; C.O. Schmidt (Carsten O.); R. Mather; V. Chouraki (Vincent); Q. Sun; S. Resnick (Susan); L.M. Rose (Lynda M.); C. Oldmeadow (Christopher); M. Stewart; B.H. Smith; V. Gudnason (Vilmundur); Q. Yang (Qiong); S.S. Mirza (Saira); J.W. Jukema; P.L. DeJager (Philip L.); T.B. Harris (Tamara); D.C. Liewald (David C.); N. Amin; L.H. Coker (Laura); O. Stegle (Oliver); O.L. Lopez; R. Schmidt; A. Teumer (Alexander); I. Ford; N. Karbalai (Nazanin); J.T. Becker; M.K. Jonsdottir (Maria K.); R. Au; R.S.N. Fehrmann (Rudolf); S. Herms (Stefan); M.A. Nalls (Michael); W. Zhao; S.T. Turner; K. Yaffe; K. Lohman (Kurt); J.C. van Swieten (John); S.L.R. Kardia; D.S. Knopman (David); W.M. Meeks (William); G. Heiss (Gerardo); E.G. Holliday (Elizabeth); P.W. Schofield; T. Tanaka (Toshiko); D.J. Stott (David J.); J. Wang (Jing); P.M. Ridker (Paul); A.J. Gow; A. Pattie (Alison); J.M. Starr (John); L.J. Hocking; N.J. Armstrong (Nicola J.); S. McLachlan (Stela); L. Shulman (Lee); L.C. Pilling (Luke); G. Eiriksdottir (Gudny); R.J. Scott; N.A. Kochan (Nicole A.); A. Palotie; Y.-C. Hsieh; J.G. Eriksson (Johan G.); A.D. Penman (Alan); R.F. Gottesman (Rebecca); B.A. Oostra (Ben); L. Yu; A.L. DeStefano (Anita L.); A. Beiser; M. Garcia; J.I. Rotter; M.M. Nöthen; A. Hofman (Albert); P.E. Slagboom (Eline); R.G.J. Westendorp; B.M. Buckley (Brendan M.); P.A. Wolf; A.G. Uitterlinden (André); B.M. Psaty (Bruce); H.J. Grabe (Hans Jörgen); S. Bandinelli (Stefania); D.I. Chasman (Daniel); F. Grodstein (Francine); K. Räikkönen (Katri); J.-C. Lambert; D.J. Porteous (David J.); J.F. Price (Jackie F.); P.S. Sachdev (Perminder); L. Ferrucci (Luigi); J. Attia (John); I. Rudan (Igor); C. Hayward; A.F. Wright; J.F. Wilson (James F); S. Cichon (Sven); L. Franke (Lude); H. Schmidt; J. Ding; A.J. de Craen (Anton); M. Fornage (Myriam); D.A. Bennett (David); I.J. Deary (Ian); M.A. Ikram (Arfan); L.J. Launer (Lenore); A.L. Fitzpatrick; S. Seshadri (Sudha); C.M. van Duijn (Cock); T.H. Mosley (Thomas H.)

    2016-01-01

    textabstractTo identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and

  16. Parent Involvement in the Special Education Eligibility Process: Implementation of Legal Mandates and Best Practices

    Science.gov (United States)

    McEvoy, Cathleen K.

    2013-01-01

    School psychologists throughout New York State were surveyed regarding their schools' policies to include parents in the special education eligibility process related to legal mandates and best practices. Differences were found in the implementation of legal mandates compared to implementation of best practices. Location differences were…

  17. A Mathematical Experience Involving Defining Processes: In-Action Definitions and Zero-Definitions

    Science.gov (United States)

    Ouvrier-Buffet, Cecile

    2011-01-01

    In this paper, a focus is made on defining processes at stake in an unfamiliar situation coming from discrete mathematics which brings surprising mathematical results. The epistemological framework of Lakatos is questioned and used for the design and the analysis of the situation. The cognitive background of Vergnaud's approach enriches the study…

  18. Parent Involvement in the Special Education Eligibility Process: Implementation of Legal Mandates and Best Practices

    Science.gov (United States)

    McEvoy, Cathleen K.

    2013-01-01

    School psychologists throughout New York State were surveyed regarding their schools' policies to include parents in the special education eligibility process related to legal mandates and best practices. Differences were found in the implementation of legal mandates compared to implementation of best practices. Location differences were…

  19. Computation of NLO Processes Involving Heavy Quarks Using Loop-Tree Duality

    CERN Document Server

    Driencourt-Mangin, Felix

    2016-01-01

    We present a new method to compute higher-order corrections to physical cross-sections, at Next-to-Leading Order and beyond. This method, based on the Loop Tree Duality, leads to locally integrable expressions in four dimensions. By introducing a physically motivated momentum mapping between the momenta involved in the real and the virtual contributions, infrared singularities naturally cancel at integrand level, without the need to introduce subtraction counter-terms. Ultraviolet singularities are dealt with by using dual representations of suitable counter-terms, with some subtleties regarding the self-energy contributions. As an example, we apply this method to compute the $1\\to2$ decay rate in the context of a scalar toy model with massive particles.

  20. New theoretical methods for studies on electrons and positrons scattering involving multichannel processes

    CERN Document Server

    Lara, O

    1995-01-01

    continued fractions are now in progress. It is well known that multichannel effects strongly influence the low-energy electron scattering by atoms and molecules. Nevertheless, the inclusion of such effects on the calculations of scattering cross sections remains a considerable task for the area researches due to the complexity of the problem. In the present study we aim to develop a new theoretical method which can be efficiently applied to the multichannel scattering studies. Two new theoretical formalisms namely the Multichannel sup - C-Functional Method have been proposed. Both methods were developed on the base of well-known distorted-wave method combined with Schwinger variational principle. In addition, an integrative method proposed by Horacek and Sasakawa in 1983, the method of continued fractions is adapted by the first time to multichannel scatterings. Numerical test of these three methods were carried out through applications to solve the multichannel scattering problems involving the interaction o...

  1. Silicon Regulates Potential Genes Involved in Major Physiological Processes in Plants to Combat Stress

    Directory of Open Access Journals (Sweden)

    Abinaya Manivannan

    2017-08-01

    Full Text Available Silicon (Si, the quasi-essential element occurs as the second most abundant element in the earth's crust. Biological importance of Si in plant kingdom has become inevitable particularly under stressed environment. In general, plants are classified as high, medium, and low silicon accumulators based on the ability of roots to absorb Si. The uptake of Si directly influence the positive effects attributed to the plant but Si supplementation proves to mitigate stress and recover plant growth even in low accumulating plants like tomato. The application of Si in soil as well as soil-less cultivation systems have resulted in the enhancement of quantitative and qualitative traits of plants even under stressed environment. Silicon possesses several mechanisms to regulate the physiological, biochemical, and antioxidant metabolism in plants to combat abiotic and biotic stresses. Nevertheless, very few reports are available on the aspect of Si-mediated molecular regulation of genes with potential role in stress tolerance. The recent advancements in the era of genomics and transcriptomics have opened an avenue for the determination of molecular rationale associated with the Si amendment to the stress alleviation in plants. Therefore, the present endeavor has attempted to describe the recent discoveries related to the regulation of vital genes involved in photosynthesis, transcription regulation, defense, water transport, polyamine synthesis, and housekeeping genes during abiotic and biotic stress alleviation by Si. Furthermore, an overview of Si-mediated modulation of multiple genes involved in stress response pathways such as phenylpropanoid pathway, jasmonic acid pathway, ABA-dependent or independent regulatory pathway have been discussed in this review.

  2. Different Involvement of Type 1, 2, and 3 Ryanodine Receptors in Memory Processes

    Science.gov (United States)

    Galeotti, Nicoletta; Quattrone, Alessandro; Vivoli, Elisa; Norcini, Monica; Bartolini, Alessandro; Ghelardini, Carla

    2008-01-01

    The administration of the ryanodine receptor (RyR) agonist 4-Cmc (0.003-9 nmol per mouse intracerebroventricularly [i.c.v.]) ameliorated memory functions, whereas the RyR antagonist ryanodine (0.0001-1 nmol per mouse i.c.v.) induced amnesia in the mouse passive avoidance test. The role of the type 1, 2, and 3 RyR isoforms in memory processes was…

  3. Increased functional connectivity with puberty in the mentalising network involved in social emotion processing.

    Science.gov (United States)

    Klapwijk, Eduard T; Goddings, Anne-Lise; Burnett Heyes, Stephanie; Bird, Geoffrey; Viner, Russell M; Blakemore, Sarah-Jayne

    2013-07-01

    This article is part of a Special Issue "Puberty and Adolescence". There is increasing evidence that puberty plays an important role in the structural and functional brain development seen in adolescence, but little is known of the pubertal influence on changes in functional connectivity. We explored how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to functional connectivity between components of a mentalising network identified to be engaged in social emotion processing by our prior work, using psychophysiological interaction (PPI) analysis. Female adolescents aged 11 to 13years were scanned whilst silently reading scenarios designed to evoke either social emotions (guilt and embarrassment) or basic emotions (disgust and fear), of which only social compared to basic emotions require the representation of another person's mental states. Pubertal stage and menarcheal status were used to assign participants to pre/early or mid/late puberty groups. We found increased functional connectivity between the dorsomedial prefrontal cortex (DMPFC) and the right posterior superior temporal sulcus (pSTS) and right temporo-parietal junction (TPJ) during social relative to basic emotion processing. Moreover, increasing oestradiol concentrations were associated with increased functional connectivity between the DMPFC and the right TPJ during social relative to basic emotion processing, independent of age. Our analysis of the PPI data by phenotypic pubertal status showed that more advanced puberty stage was associated with enhanced functional connectivity between the DMPFC and the left anterior temporal cortex (ATC) during social relative to basic emotion processing, also independent of age. Our results suggest increased functional maturation of the social brain network with the advancement of puberty in girls.

  4. Increased functional connectivity with puberty in the mentalising network involved in social emotion processing

    OpenAIRE

    Klapwijk, Eduard T.; Goddings, Anne-Lise; Heyes, Stephanie Burnett; Bird, Geoffrey; Viner, Russell M; Blakemore, Sarah-Jayne

    2013-01-01

    There is increasing evidence that puberty plays an important role in the structural and functional brain development seen in adolescence, but little is known of the pubertal influence on changes in functional connectivity. We explored how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to functional connectivity between components of a mentalising network identified to be engaged in social emotion processing by our p...

  5. Sentential context modulates the involvement of the motor cortex in action language processing: an FMRI study.

    Science.gov (United States)

    Schuil, Karen D I; Smits, Marion; Zwaan, Rolf A

    2013-01-01

    Theories of embodied cognition propose that language comprehension is based on perceptual and motor processes. More specifically, it is hypothesized that neurons processing verbs describing bodily actions, and those that process the corresponding physical actions, fire simultaneously during action verb learning. Thus the concept and motor activation become strongly linked. According to this view, the language-induced activation of the neural substrates for action is automatic. By contrast, a weak view of embodied cognition proposes that activation of these motor regions is modulated by context. In recent studies it was found that action verbs in literal sentences activate the motor system, while mixed results were observed for action verbs in non-literal sentences. Thus, whether the recruitment of motor regions is automatic or context dependent remains a question. We investigated functional magnetic resonance imaging activation in response to non-literal and literal sentences including arm and leg related actions. The sentence structure was such that the action verb was the last word in the subordinate clause. Thus, the constraining context was presented well before the verb. Region of interest analyses showed that action verbs in literal context engage the motor regions to a greater extent than non-literal action verbs. There was no evidence for a semantic somatotopic organization of the motor cortex. Taken together, these results indicate that during comprehension, the degree to which motor regions are recruited is context dependent, supporting the weak view of embodied cognition.

  6. Process evaluation of the health education resource Abre los Ojos for street-involved youth in Medellín

    Directory of Open Access Journals (Sweden)

    John L. Wylie

    2012-02-01

    Full Text Available Objective: Conduct a process evaluation of a health education resource (pamphlet¸ Abre los Ojos, designed for street-involved youth in Medellín. The primary foci of the evaluation were the process of developing the resource and youth’s subsequent perception of the resource. Methodology: Drawing upon both qualitative and quantitative data, a process evaluation was undertaken. Ninety four street-involved youth between the ages of 14–24 years completed surveys about the resource. These semi-structured interviews were key for the information about youth perception of the resource. In addition to individual interviews, prior to resource creation, a series of focus groups were integral for the development of the resource. Results: The process of consulting with the target population through the focus groups was effective in obtaining their ideas and feedback about what type of content they would like to see in a health education resource, and how they wanted that content presented. After distribution, participants described that Abre los Ojos contained information that was valuable and relevant to their experiences. While not a primary focus of this evaluation, the individual interviews were also able to provide some preliminary insight into whether Abre los Ojos was an effective means for participants to increase their knowledge of content included in the resource. Conclusion: The collaborative process of jointly developing the resource content in partnership with the youth proved very worthwhile. While our research team chose to include information about HIV, through focus group dialogue, the youth themselves determined the additional content themes (piercings, use of solvents, and description of life on the street. The resulting resource was well-received by members of the street-involved population who had not been involved in its design.

  7. Differentiation of cellular processes involved in the induction and maintenance of stimulated neutrophil adherence.

    Science.gov (United States)

    English, D; Gabig, T G

    1986-05-01

    Neutrophil adherence stimulated by phorbol myristate acetate (PMA) was investigated by quantitating the attachment of 51Cr-labeled neutrophils to plastic surfaces and to the endothelium of umbilical veins mounted in compartmentalized Lucite chambers. PMA-induced adherence could be functionally separated into an induction phase requiring cellular metabolism and a Mg++ dependent maintenance phase that was independent of cellular metabolism. Thus, metabolic inhibitors (N-ethylmaleimide, 2-deoxyglucose) blocked adherence when added to neutrophils prior to PMA, but did not cause detachment of cells adhering as a consequence of prior exposure to PMA. PMA failed to induce adherence of neutrophils incubated at low (0.4 degree C) temperature, but temperature reduction, even for prolonged periods, did not cause detachment of adherent cells. Thus, the attractive forces that mediate stimulated adherence persist independently of any sustained metabolic response to the inducing stimulus. However, removal of Mg++ from the media above adherent cells resulted in immediate detachment, indicating that the cation was required for the persistent expression or maintenance of the attractive forces involved. The extent of stimulated adherence correlated well with the extent of degranulation when rates were varied by limiting the incubation time or stimulus concentration. This correlation was not absolute; in the absence of Mg++, PMA induced degranulation normally but failed to enhance adherence. To explain these findings, we investigated the possibility that PMA-stimulated adherence was maintained by Mg++-dependent cellular adherence molecules released during exocytosis. Supernatants of stimulated neutrophils were devoid of adherence-promoting activity, and only weak activity was recovered in supernatants of mechanically disrupted neutrophils. PMA effectively stimulated the tight adherence of degranulated neutrophil cytoplasts to plastic surfaces and did so in the absence of stimulated

  8. Synthesis and characterization of magnetically hard Fe-Pt alloy nanoparticles and nano-islands

    Science.gov (United States)

    Hu, Xiaocao

    In this dissertation, we explored the fabrication of FePt nanoparticles and nano-islands with the face-centered tetragonal (fct, L10) phase prepared by both chemical synthesis routes and physical vapor deposition. Microstructure and magnetic properties characterizations were used to gain a fundamental understanding of the nano-structure formation and atomic ordering behavior and determine the possible applications in the next generation ultra-high density magnetic storage media. FePt nanoparticles prepared by thermal decomposition of iron pentacarbonyl [Fe(CO)5] have been widely investigated and by tuning the processing procedure monodispersed FePt nanoparticles with good assembly can be obtained. The as-made FePt nanoparticles are usually in the magnetically soft face-centered cubic (fcc) phase. To transformation to the fct phase, post-annealing at above 600°C is needed which, however, introduces undesirable agglomeration and sintering. To address this problem, we used three different fabrication processes which are discussed below. In the first fabrication experiment, the FePt nanoparticles were fabricated by a novel environmental friendly method involving crystalline saline complex hexaaquairon (II) hexachloroplatinate ([Fe(H2O)6]PtCl 6) with a special layered structure. Then the precursor was ball milled with NaCl and annealed at temperatures above 400°C under a reducing atmosphere of forming gas (95% Ar and 5% H2) FePt nanoparticles were obtained after washing away NaCl with deionized water. This method avoids the use of the very poisonous Fe(CO)5 and other organic solvents such as oleylamine and oleic acid. Instead, environmentally friendly NaCl and water were used. The size of FePt nanoparticles was controlled by varying the proportion of precursor and NaCl (from 10mg/20g to 50mg/20g). Particles with size in the range of 6.2--13.2 nm were obtained. All the nanoparticles annealed above 400°C are in the highly ordered fct phase with a coercivity range of 4

  9. The 5-HT7 receptor is involved in allocentric spatial memory information processing

    OpenAIRE

    Sarkisyan, Gor; Hedlund, Peter B.

    2009-01-01

    The hippocampus has been implicated in aspects of spatial memory. Its ability to generate new neurons has been suggested to play a role in memory formation. Hippocampal serotonin (5-HT) neurotransmission has also been proposed as a contributor to memory processing. Studies have shown that the 5-HT7 receptor is present in the hippocampus in relatively high abundance. Thus the aim of the present study was to investigate the possible role of the 5-HT7 receptor in spatial memory using 5-HT7 recep...

  10. Trait-based affective processes in alcohol-involved "risk behaviors".

    Science.gov (United States)

    Wray, Tyler B; Simons, Jeffrey S; Dvorak, Robert D; Gaher, Raluca M

    2012-11-01

    This study tested a theoretical model of alcohol use, markers of extreme intoxication, and risk behavior as a function of trait affect, distress tolerance, and affect-based behavior dysregulation. Positive affective pathways to risk behavior were primarily expected to be indirect via high levels of alcohol use, while negative affect paths were expected to be more directly associated with engagement in risk behavior. In addition, we expected trait affectivity and distress tolerance would primarily exhibit relationships with alcohol use and problems through behavioral dysregulation occurring during extreme affective states. To evaluate these hypotheses, we tested a SEM with three alcohol-related outcomes: "Typical" alcohol use, "blackout" drinking, and risk behavior. High trait negative affect and low tolerance for affective distress contribute to difficulty controlling behavior when negatively aroused and this is directly associated with increased risk behavior when drinking. In contrast, associations between positive urgency and risk behaviors are indirect via increased alcohol consumption. Positive affectivity exhibited both inverse and positive effects in the model, with the net effect on alcohol outcomes being insignificant. These findings contribute important information about the distinct pathways between affect, alcohol use, and alcohol-involved risk behavior among college students.

  11. The family as window onto the world of the patient: involving patients and families in the decision-making process.

    Science.gov (United States)

    Chambers-Evans, Jane

    2002-10-01

    The need to involve family members as patient advocates and as surrogates when patients are unable to speak for themselves is not an issue. What continues to be debated are the methods for involving family members in the decision-making process. Such decisions can be complex and the environment in which they are made can be chaotic, while clinicians' approach to decision-making is often seen as insensitive. Families struggle with the emotional burden of their role and clinicians struggle to translate complex information into comprehensible, meaningful, and practical language. There is a need to examine clinical practice to determine which approaches to involving family members are preferable from a philosophical as well as a practical point of view. The paper explores the many facets of the surrogate decision-making role and suggests a reorientation of current models of the professional-surrogate relationship.

  12. Ethanolic fermentation in whey and whey-molasses mixtures. Pt. 2. Two-stage fermentation process of ethanol production from whey and beet molasses

    Energy Technology Data Exchange (ETDEWEB)

    Zakrzewski, E.; Zmarlicki, S.

    1988-01-01

    A two-stage fermentation process has been developed for ethanol production from regular or partly concentrated whey and molasses. In the first stage ethanolic fermentation in whey is performed with Kluyveromyces marxianus subsp. marxianus. Such prefermented whey is then used for dilution of molasses instead of water and the resulting medium subjected to the second stage fermentation performed with Saccharomyces cerevisiae. The process enables complete fermentation of lactose and all fermentble sugars from molasses, leading to an ethanol content of about 10% in the final medium, which makes the distillation much more economical than the separate processing of whey and molasses into spirit.

  13. Beta-delayed fission probabilities of transfermium nuclei, involved in the r-process

    Science.gov (United States)

    Panov, I.; Lutostansky, Yu; Thielemann, F.-K.

    2016-01-01

    For the nucleosynthesis of heavy and superheavy nuclei fission becomes very important when the r-process runs in a very high neutron density environment. In part, fission is responsible for the formation of heavy nuclei due to the inclusion of fission products as new seed nuclei (fission cycling). More than that, beta-delayed fission, along with spontaneous fission, is responsible in the late stages of the r-process for the suppression of superheavy element yields. For beta-delayed fission probability calculations a model description of the beta-strength- functions is required. Extended theoretical predictions for astro-physical applications were provided long ago, and new predictions also for superheavy nuclei with uptodate nuclear input are needed. For the further extension of data to heavier transactinides the models of strength- functions should be modified, taking into account more complicated level schemes. In our present calculations the strength-function model is based on the quasi-particle approximation of Finite Fermi Systems Theory. The probabilities of beta-delayed fission and beta-delayed neutron emission are calculated for some transfermium neutron-rich nuclei, and the influence of beta-delayed fission upon superheavy element formation is discussed.

  14. Can the BestGrid Process Improve Stakeholder Involvement in Electricity Transmission Projects?

    Directory of Open Access Journals (Sweden)

    Nadejda Komendantova

    2015-08-01

    Full Text Available The European Union has set ambitious targets for deployment of renewable energy sources to reach goals of climate change mitigation and energy security policies. However, the current state of electricity transmission infrastructure is a major bottleneck for further scaling up of renewable energy in the EU. Several thousands of kilometers of new lines have to be constructed and upgraded to accommodate growing volumes of intermittent renewable electricity. In many countries, construction of electricity transmission projects has been delayed for several years due to concerns of local stakeholders. The innovative BESTGRID approach, reported here, brings together transmission system operators (TSOs and non-governmental organizations (NGOs to discuss and understand the nature of stakeholder concerns. This paper has three objectives: (1 to understand stakeholder concerns about the deployment of electricity transmission grids in four pilot projects according to five guiding principles: need, transparency, engagement, environment, and impacts on human health as well as benefits; (2 to understand how these principles can be addressed to provide a basis for better decision-making outcomes; and (3 to evaluate the BESTGRID process based on feedback received from stakeholders and the level of participation achieved according to the ladder of Arnstein. This paper goes beyond a discussion of “measures to mitigate opposition” to understand how dialogue between TSOs and the public—represented mainly by NGOs and policy-makers—might lead to a better decision-making process and more sustainable electricity transmission infrastructure deployment.

  15. Perceptual grouping does not affect multi-attribute decision making if no processing costs are involved.

    Science.gov (United States)

    Ettlin, Florence; Bröder, Arndt

    2015-05-01

    Adaptive strategy selection implies that a decision strategy is chosen based on its fit to the task and situation. However, other aspects, such as the way information is presented, can determine information search behavior; especially when the application of certain strategies over others is facilitated. But are such display effects on multi-attribute decisions also at work when the manipulation does not entail differential costs for different decision strategies? Three Mouselab experiments with hidden information and one eye tracking experiment with an open information board revealed that decision behavior is unaffected by purely perceptual manipulations of the display based on Gestalt principles; that is, based on manipulations that induce no noteworthy processing costs for different information search patterns. We discuss our results in the context of previous findings on display effects; specifically, how the combination of these findings and our results reveal the crucial role of differential processing costs for different strategies for the emergence of display effects. This finding describes a boundary condition of the commonly acknowledged influence of information displays and is in line with the ideas of adaptive strategy selection and cost-benefit tradeoffs.

  16. RadA: A protein involved in DNA damage repair processes of Deinococcus radiodurans R1

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qing; ZHANG Xinjue; XU Hong; XU Bujin; HUA Yuejin

    2006-01-01

    RadA is highly conserved in bacteria and belongs to the RecA/RadA/Rad51 protein superfamily found in bacteria, archaea and eukarya. In Archaea, it plays a critical role in homologous recombination process due to its RecA-like function. In Escherichia coli, it takes part in conjugational recombination and DNA repair but is not as important as that of archaea. Using PSI-BLAST searches, we found that Deinococcus radiodurans RadA had a higher similarity to that of bacteria than archaea and eukarya. Disruption of radA gene in D. radiodurans resulted in a modestly decreased resistance to gamma radiation and ultraviolet, but had no effect on the resistance to hydrogen peroxide. Complementation of the radA disruptant by both E. coli radA and D.radiodurans radA could fully restore its resistance to gamma radiation and ultraviolet irradiation. Further domain function analyses of D. radiodurans RadA showed that the absence of the zinc finger domain resulted in a slightly more sensitive phenotype togamma and UV radiation than that of the radA mutant,while the absence of the Lon protease domain exhibited a slightly increased resistance to gamma and UV radiation. These data suggest that D. radiodurans RadA does play an important role in the DNA damage repair processes and its three different domains have different functions.

  17. The Leech Nervous System: A Valuable Model to Study the Microglia Involvement in Regenerative Processes

    Directory of Open Access Journals (Sweden)

    Françoise Le Marrec-Croq

    2013-01-01

    Full Text Available Microglia are intrinsic components of the central nervous system (CNS. During pathologies in mammals, inflammatory processes implicate the resident microglia and the infiltration of blood cells including macrophages. Functions of microglia appear to be complex as they exhibit both neuroprotective and neurotoxic effects during neuropathological conditions in vivo and in vitro. The medicinal leech Hirudo medicinalis is a well-known model in neurobiology due to its ability to naturally repair its CNS following injury. Considering the low infiltration of blood cells in this process, the leech CNS is studied to specify the activation mechanisms of only resident microglial cells. The microglia recruitment is known to be essential for the usual sprouting of injured axons and does not require any other glial cells. The present review will describe the questions which are addressed to understand the nerve repair. They will discuss the implication of leech factors in the microglial accumulation, the identification of nerve cells producing these molecules, and the study of different microglial subsets. Those questions aim to better understand the mechanisms of microglial cell recruitment and their crosstalk with damaged neurons. The study of this dialog is necessary to elucidate the balance of the inflammation leading to the leech CNS repair.

  18. Conflict monitoring and stimulus categorization processes involved in the prosocial attitude implicit association test: Evidence from event-related potentials.

    Science.gov (United States)

    Xiao, Fengqiu; Zheng, Zhiwei; Wang, Ya; Cui, Jifang; Chen, Yinghe

    2015-08-01

    The implicit association test (IAT) is a promising method used to assess individual implicit attitudes by indirectly measuring the strengths of associations between target and attribute categories. To date, the cognitive processes involved in the prosocial attitude IAT task have received little attention. The present study examined the temporal dynamics of the IAT that measures prosocial attitude using event-related potentials (ERPs). ERP results revealed enhanced N2 amplitudes for incongruent trials when compared with congruent trials and enhanced P300 amplitudes for congruent trials when compared with incongruent trials. In addition, the N2 amplitude differences were significantly correlated with individual prosocial behavior (the amount of donation). Our findings suggest that conflict monitoring and stimulus categorization processes are involved in the prosocial attitude IAT task and that the ERP indices of IATs that measure prosocial attitude may predict individual prosocial behavior.

  19. Involvement of the modifier gene of a human Mendelian disorder in a negative selection process.

    Directory of Open Access Journals (Sweden)

    Isabelle Jéru

    Full Text Available BACKGROUND: Identification of modifier genes and characterization of their effects represent major challenges in human genetics. SAA1 is one of the few modifiers identified in humans: this gene influences the risk of renal amyloidosis (RA in patients with familial Mediterranean fever (FMF, a Mendelian autoinflammatory disorder associated with mutations in MEFV. Indeed, the SAA1 alpha homozygous genotype and the p.Met694Val homozygous genotype at the MEFV locus are two main risk factors for RA. METHODOLOGY/PRINCIPAL FINDINGS: HERE, WE INVESTIGATED ARMENIAN FMF PATIENTS AND CONTROLS FROM TWO NEIGHBORING COUNTRIES: Armenia, where RA is frequent (24%, and Karabakh, where RA is rare (2.5%. Sequencing of MEFV revealed similar frequencies of p.Met694Val homozygotes in the two groups of patients. However, a major deficit of SAA1 alpha homozygotes was found among Karabakhian patients (4% as compared to Armenian patients (24% (p = 5.10(-5. Most importantly, we observed deviations from Hardy-Weinberg equilibrium (HWE in the two groups of patients, and unexpectedly, in opposite directions, whereas, in the two control populations, genotype distributions at this locus were similar and complied with (HWE. CONCLUSIONS/SIGNIFICANCE: The excess of SAA1alpha homozygotes among Armenian patients could be explained by the recruitment of patients with severe phenotypes. In contrast, a population-based study revealed that the deficit of alpha/alpha among Karabakhian patients would result from a negative selection against carriers of this genotype. This study, which provides new insights into the role of SAA1 in the pathophysiology of FMF, represents the first example of deviations from HWE and selection involving the modifier gene of a Mendelian disorder.

  20. Potential Involvement of P2 Receptors in the Pathological Processes of Hyperthyroidism: A Pilot Study.

    Science.gov (United States)

    Hong, Wu; Li, Guodong; Nie, Yijun; Zou, Lifang; Zhang, Xi; Liu, Shuangmei; Li, Guilin; Xu, Hong; Zhang, Chun-Ping; Liang, Shangdong

    2016-05-01

    Symptoms of hyperthyroidism manifest mainly as changes in the nervous and metabolic systems. Whether P2X receptors (ionotropic ATP purinergic receptors, including P2X3 receptor and P2X7 receptor) are involved in the alterations of these disorders still remains unclear. Thus, this study aimed to assess the association of hyperthyroidism with the expression of P2X3 and P2X7 receptors and the concentrations of ATP in blood leukocytes and catecholamine. Twelve healthy subjects and twelve patients diagnosed with hyperthyroidism were recruited. Serum free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) levels had been detected by chemiluminescence method. Meanwhile, the catecholamine levels (including adrenaline, noradrenaline, and dopamine) in plasma, ATP level and P2X receptors (including P2X3 receptor and P2X7 receptor) in peripheral blood had been detected by high performance liquid chromatography, bioluminescence method, and reverse transcription polymerase chain reaction, respectively. Levels of epinephrine and norepinephrine were significantly higher in the hyperthyroidism group compared with the control group. The concentration of ATP in the hyperthyroidism group was significantly higher than its in the control group. The expression of P2X3 mRNA and P2X7 mRNA in hyperthyroidism group were significantly increased compared with those in control group. In a conclusion, there is a relationship between the elevated expression of P2X3 receptor and P2X7 receptor in peripheral blood leukocytes and high serum epinephrine and norepinephrine levels in hyperthyroidism patients.

  1. Different forms of MARCKS protein are involved in memory formation in the learning process of imprinting.

    Science.gov (United States)

    Solomonia, Revaz O; Apkhazava, David; Nozadze, Maia; Jackson, Antony P; McCabe, Brian J; Horn, Gabriel

    2008-06-01

    There is strong evidence that a restricted part of the chick forebrain, the IMM (formerly IMHV), stores information acquired through the learning process of visual imprinting. Twenty-four hours after imprinting training, a learning-specific increase in amount of myristoylated, alanine-rich C-kinase substrate (MARCKS) protein is known to occur in the homogenate fraction of IMM. We investigated the two components of this fraction, membrane-bound and cytoplasmic-phosphorylated MARCKS. In IMM, amount of membrane-bound MARCKS, but not of cytoplasmic-phosphorylated MARCKS, increased as chicks learned. No changes were observed for either form of MARCKS in PPN, a control forebrain region. The results indicate that there is a learning-specific increase in membrane-bound, non-phosphorylated MARCKS 24 h after training. This increase might contribute to stabilization of synaptic morphology.

  2. The global methane cycle: recent advances in understanding the microbial processes involved.

    Science.gov (United States)

    Conrad, Ralf

    2009-10-01

    The global budget of atmospheric CH4 , which is on the order of 500-600 Tg CH4 per year, is mainly the result of environmental microbial processes, such as archaeal methanogenesis in wetlands, rice fields, ruminant and termite digestive systems and of microbial methane oxidation under anoxic and oxic conditions. This review highlights recent progress in the research of anaerobic CH4 oxidation, of CH4 production in the plant rhizosphere, of CH4 serving as substrate for the aquatic trophic food chain and the discovery of novel aerobic methanotrophs. It also emphasizes progress and deficiencies in our knowledge of microbial utilization of low atmospheric CH4 concentrations in soil, CH4 production in the plant canopy, intestinal methanogenesis and CH4 production in pelagic water. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.

  3. The variability of processes involved in transgene dispersal - case studies from Brassica and related genera

    DEFF Research Database (Denmark)

    Bagger Jørgensen, Rikke; Hauser, Thure Pavlo; D'Hertefeldt, T.

    2009-01-01

    Background, aim, and scope We strive to predict consequences of genetically modified plants (GMPs) being cultivated openly in the environment, as human and animal health, biodiversity, agricultural practise and farmers’ economy could be affected. Therefore, it is unfortunate that the risk...... of fitness parameters. Monitoring of the extent of spontaneous introgression in natural populations was also performed. Modelling was used as an additional tool to identify key parameters in gene flow. Results The GM plant may affect the environment directly or indirectly by dispersal of the transgene....... In the present review, this is illustrated through a bunch of examples mostly from our own research on oilseed rape, Brassica napus. In the Brassica cases, the variability affected all five main steps in the process of gene dispersal. The modelling performed suggests that in Brassica, differences in fitness...

  4. Anticonvulsants Teratogenic Mechanism Involves Alteration of Bioelectrically-controlled Processes in the Embryo. A hypothesis

    Science.gov (United States)

    Hernández-Díaz, Sonia; Levin, Michael

    2014-01-01

    Maternal use of anticonvulsants during the first trimester of pregnancy has been associated with an elevated risk of major congenital malformations in the offspring. Whether the increased risk is caused by the specific pharmacological mechanisms of certain anticonvulsants, the underlying epilepsy, or common genetic or environmental risk factors shared by epilepsy and malformations is controversial. We hypothesize that anticonvulsant therapies during pregnancy that attain more successful inhibition of neurotransmission might lead to both better seizure control in the mother and stronger alteration of bioelectrically-controlled processes in the embryo that result in structural malformations. If our theory were correct, development of pharmaceuticals that do not alter cell resting transmembrane voltage levels could result in safer drugs. PMID:24815983

  5. Differential bilateral involvement of the parietal gyrus during predicative metaphor processing: an auditory fMRI study.

    Science.gov (United States)

    Obert, Alexandre; Gierski, Fabien; Calmus, Arnaud; Portefaix, Christophe; Declercq, Christelle; Pierot, Laurent; Caillies, Stéphanie

    2014-10-01

    Despite the growing literature on figurative language processing, there is still debate as to which cognitive processes and neural bases are involved. Furthermore, most studies have focused on nominal metaphor processing without any context, and very few have used auditory presentation. We therefore investigated the neural bases of the comprehension of predicative metaphors presented in a brief context, in an auditory, ecological way. The comprehension of their literal counterparts served as a control condition. We also investigated the link between working memory and verbal skills and regional activation. Comparisons of metaphorical and literal conditions revealed bilateral activation of parietal areas including the left angular (lAG) and right inferior parietal gyri (rIPG) and right precuneus. Only verbal skills were associated with lAG (but not rIPG) activation. These results indicated that predicative metaphor comprehension share common activations with other metaphors. Furthermore, individual verbal skills could have an impact on figurative language processing.

  6. Changes in Pre-service Science Teachers' Understandings After Being Involved in Explicit Nature of Science and Socioscientific Argumentation Processes

    Science.gov (United States)

    Kutluca, A. Y.; Aydın, A.

    2017-09-01

    The study explored the changes in pre-service science teachers' understanding of the nature of science and their opinions about the nature of science, science teaching and argumentation after their participation in explicit nature of science (NOS) and socioscientific argumentation processes. The participants were 56 third-grade pre-service science teachers studying in a state university in Turkey. The treatment group comprised 27 participants, and there were 29 participants in the comparison group. The comparison group participants were involved in a student-centred science-teaching process, and the participants of the treatment group were involved in explicit NOS and socioscientific argumentation processes. In the study, which lasted a total of 11 weeks, a NOS-as-argumentation questionnaire was administered to all the participants to determine their understanding of NOS at the beginning and end of the data collection process, and six random participants of the treatment group participated in semi-structured interview questions in order to further understand their views regarding NOS, science teaching and argumentation. Qualitative and quantitative data analysis revealed that the explicit NOS and socioscientific argumentation processes had a significant effect on pre-service science teachers' NOS understandings. Furthermore, NOS, argumentation and science teaching views of the participants in the treatment group showed a positive change. The results of this study are discussed in light of the related literature, and suggestions are made within the context of contribution to science-teaching literature, improvement of education quality and education of pre-service teachers.

  7. Selective formation of tetrahedral Pt nanocrystals from K2PtCl6/PVP

    Institute of Scientific and Technical Information of China (English)

    YU Yingtao; XU Boqing

    2003-01-01

    Tetrahedral platinum (Pt) nanocrystals (3-8 nm) are synthesized in high selectivity (ca. 80%) from hydrogen reduction of aqueous K2PtCl6 by using polyvinylpyrrolidone (PVP: Mw≈360000) as a protector. Morphology (TEM) measurements of the metal colloids and UV-Vis absorption of the colloidal solution are employed to monitor the tetrahedron formation during the syntheses with varying K2PtCl6/PVP ratios. The results clearly show a two-stage process for the selective formation of tetrahedral nanocrystals. Rapid nucleation and crystal formation at the early stage result in round-like crystallites and the external facet evolution in thereafter slow crystal growth leads selectively to the formation of the tetrahedrons.

  8. TGF-beta1 regulates human brain pericyte inflammatory processes involved in neurovasculature function.

    Science.gov (United States)

    Rustenhoven, Justin; Aalderink, Miranda; Scotter, Emma L; Oldfield, Robyn L; Bergin, Peter S; Mee, Edward W; Graham, E Scott; Faull, Richard L M; Curtis, Maurice A; Park, Thomas I-H; Dragunow, Mike

    2016-02-11

    adhesion molecules involved in CNS leukocyte trafficking and the modulation of microglial function, as well as reduced the phagocytic ability of pericytes. However, TGFβ1 also enhanced the expression of classical pro-inflammatory cytokines and enzymes which can disrupt BBB functioning, suggesting that pericytes adopt a phenotype which is neither solely pro- nor anti-inflammatory. Whilst the effects of pericyte modulation by TGFβ1 in vivo are difficult to infer, the reduction in pericyte proliferation together with the elevated IL-6, MMP-2 and NOX4 and reduced phagocytosis suggests a detrimental action of TGFβ1 on neurovasculature.

  9. Concepts in context: Processing mental state concepts with internal or external focus involves different neural systems.

    Science.gov (United States)

    Oosterwijk, Suzanne; Mackey, Scott; Wilson-Mendenhall, Christine; Winkielman, Piotr; Paulus, Martin P

    2015-01-01

    According to embodied cognition theories, concepts are contextually situated and grounded in neural systems that produce experiential states. This view predicts that processing mental state concepts recruits neural regions associated with different aspects of experience depending on the context in which people understand a concept. This neuroimaging study tested this prediction using a set of sentences that described emotional (e.g., fear, joy) and nonemotional (e.g., thinking, hunger) mental states with internal focus (i.e., focusing on bodily sensations and introspection) or external focus (i.e., focusing on expression and action). Consistent with our predictions, data suggested that the inferior frontal gyrus, a region associated with action representation, was engaged more by external than internal sentences. By contrast, the ventromedial prefrontal cortex, a region associated with the generation of internal states, was engaged more by internal emotion sentences than external sentence categories. Similar patterns emerged when we examined the relationship between neural activity and independent ratings of sentence focus. Furthermore, ratings of emotion were associated with activation in the medial prefrontal cortex, whereas ratings of activity were associated with activation in the inferior frontal gyrus. These results suggest that mental state concepts are represented in a dynamic way, using context-relevant interoceptive and sensorimotor resources.

  10. Plant immunity induced by COS-OGA elicitor is a cumulative process that involves salicylic acid.

    Science.gov (United States)

    van Aubel, Géraldine; Cambier, Pierre; Dieu, Marc; Van Cutsem, Pierre

    2016-06-01

    Plant innate immunity offers considerable opportunities for plant protection but beside flagellin and chitin, not many molecules and their receptors have been extensively characterized and very few have successfully reached the field. COS-OGA, an elicitor that combines cationic chitosan oligomers (COS) with anionic pectin oligomers (OGA), efficiently protected tomato (Solanum lycopersicum) grown in greenhouse against powdery mildew (Leveillula taurica). Leaf proteomic analysis of plants sprayed with COS-OGA showed accumulation of Pathogenesis-Related proteins (PR), especially subtilisin-like proteases. qRT-PCR confirmed upregulation of PR-proteins and salicylic acid (SA)-related genes while expression of jasmonic acid/ethylene-associated genes was not modified. SA concentration and class III peroxidase activity were increased in leaves and appeared to be a cumulative process dependent on the number of sprayings with the elicitor. These results suggest a systemic acquired resistance (SAR) mechanism of action of the COS-OGA elicitor and highlight the importance of repeated applications to ensure efficient protection against disease.

  11. Acoustic features involved in the neighbour-stranger vocal recognition process in male Australian fur seals.

    Science.gov (United States)

    Tripovich, J S; Charrier, I; Rogers, T L; Canfield, R; Arnould, J P Y

    2008-09-01

    Many territorial species have the ability to recognise neighbours from stranger individuals. If the neighbouring individual is assumed to pose less of a threat, the territorial individual responds less and avoids unnecessary confrontations with familiar individuals at established boundaries, thus avoiding the costly energy expenditure associated with fighting. Territorial male Australian fur seals respond more to strangers than to neighbouring males. The present study evaluated which acoustic features were important in the neighbour-stranger recognition process in male Australian fur seals. The results reveal that there was an increase in response strength or intensity from males when they heard more bark units, indicating the importance of repetition to detect a caller. However, lengthening and shortening the inter-unit spaces, (i.e. changing the rhythm of the call) did not appear to significantly affect an animal's response. In addition, the whole frequency spectrum was considered important to recognition with results suggesting that they may vary in their importance. A call containing the dominant and surrounding harmonics was considered important to a male's ability to recognise its neighbour. Furthermore, recognition occurs even with a partial bark, but males need to hear between 25 and 75% of each bark unit from neighbouring seals. Our study highlights which acoustic features induce stronger or weaker responses from territorial males, decoding the important features in neighbour-stranger recognition.

  12. Type IV Secretion System Is Not Involved in Infection Process in Citrus.

    Science.gov (United States)

    Jacob, Tiago Rinaldi; de Laia, Marcelo Luiz; Moreira, Leandro Marcio; Gonçalves, Janaína Fernandes; Carvalho, Flavia Maria de Souza; Ferro, Maria Inês Tiraboschi; Ferro, Jesus Aparecido

    2014-01-01

    The type IV secretion system (T4SS) is used by Gram-negative bacteria to translocate protein and DNA substrates across the cell envelope and into target cells. Xanthomonas citri subsp. citri contains two copies of the T4SS, one in the chromosome and the other is plasmid-encoded. To understand the conditions that induce expression of the T4SS in Xcc, we analyzed, in vitro and in planta, the expression of 18 ORFs from the T4SS and 7 hypothetical flanking genes by RT-qPCR. As a positive control, we also evaluated the expression of 29 ORFs from the type III secretion system (T3SS), since these genes are known to be expressed during plant infection condition, but not necessarily in standard culture medium. From the 29 T3SS genes analyzed by qPCR, only hrpA was downregulated at 72 h after inoculation. All genes associated with the T4SS were downregulated on Citrus leaves 72 h after inoculation. Our results showed that unlike the T3SS, the T4SS is not induced during the infection process.

  13. Aminopeptidase N (CD13 Is Involved in Phagocytic Processes in Human Dendritic Cells and Macrophages

    Directory of Open Access Journals (Sweden)

    Mónica I. Villaseñor-Cardoso

    2013-01-01

    Full Text Available Aminopeptidase N (APN or CD13 is a membrane ectopeptidase expressed by many cell types, including myelomonocytic lineage cells: monocytes, macrophages, and dendritic cells. CD13 is known to regulate the biological activity of various peptides by proteolysis, and it has been proposed that CD13 also participates in several functions such as angiogenesis, cell adhesion, metastasis, and tumor invasion. We had previously reported that, in human monocytes and macrophages, CD13 modulates the phagocytosis mediated by receptors for the Fc portion of IgG antibodies (FcγRs. In this work, we analyzed the possible interaction of CD13 with other phagocytic receptors. We found out that the cross-linking of CD13 positively modulates the phagocytosis mediated by receptors of the innate immune system, since a significant increase in the phagocytosis of zymosan particles or heat-killed E. coli was observed when CD13 was cross-linked using anti-CD13 antibodies, in both macrophages and dendritic cells. Also, we observed that, during the phagocytosis of zymosan, CD13 redistributes and is internalized into the phagosome. These findings suggest that, besides its known functions, CD13 participates in phagocytic processes in dendritic cells and macrophages.

  14. The diagonal spin basis and calculation of processes involving polarized particles

    CERN Document Server

    Galynsky, M V

    1998-01-01

    The review of developed by the authors new techniques for covariant calculation of matrix elements in QED, the so-called formalism of "Diagonal Spin Basis" (DSB), is presented. In DSB spin 4-vectors of in- and out- fermions are expressed just in terms of their 4-momenta. In this approach the little Lorentz group, common for the initial and final states,is realized. This brings the spin operators of in- and out-particles to coincidence. The developed approach is valid both for massive fermions and for massless ones. There occur no problems with accounting for spin flip amplitudes in it. Just 4-momenta of particles participating in reactions are required in it to construct the mathematical apparatus for calculations of matrix elements. We apply this formalism to the next processes: 1) Möller and Bhabha bremsstrahlung ($e^{\\pm}e^- \\to e^{\\pm}e^- \\gamma$) in the ultrarelativistic limit when initial particles and photon are helicity polarized; 2) Compton back-scattering of photons of intensive circularly polarize...

  15. The Pt(111)/Electrolyte Interface under Oxygen Reduction Reaction Conditions

    DEFF Research Database (Denmark)

    Bondarenko, A.S.; Stephens, Ifan; Hansen, Heine Anton;

    2011-01-01

    between the adsorbate and Pt surface atoms (0.45−1.15 V vs RHE). An equivalent electric circuit is proposed to model the Pt(111)/electrolyte interface under ORR conditions within the selected potential window. This equivalent circuit reflects three processes with different time constants, which occur...... simultaneously during the ORR at Pt(111). Density functional theory (DFT) calculations were used to correlate and interpret the results of the measurements. The calculations indicate that the coadsorption of ClO4* and Cl* with OH* is unlikely. Our analysis suggests that the two-dimensional (2D) structures formed...

  16. Alveolar process fractures in the permanent dentition. Part 2. The risk of healing complications in teeth involved in an alveolar process fracture

    DEFF Research Database (Denmark)

    Lauridsen, Eva; Gerds, Thomas; Andreasen, Jens Ove

    2016-01-01

    for PN (age, fracture in relation to apex, displacement, gingival injury, degree of repositioning, type of splint, duration of splinting, treatment delay, and antibiotics) were analyzed for mature teeth using Cox regression. The level of significance was 5%. RESULTS: Immature: No severe complications (PN.......3-3.5), P = 0.003), and age >30 years (HR: 2.3 (95% CI: 1.1-4.6), P = 0.02). The type of splint (rigid or flexible), the duration of splinting (more or less than 4 weeks), and the administration of antibiotics did not affect the risk of PN. CONCLUSION: Teeth involved in alveolar process fractures appear......AIM: To analyze the risk of pulp canal obliteration (PCO), pulp necrosis (PN), repair-related resorption (RRR), infection-related resorption (IRR), ankylosis-related resorption (ARR), marginal bone loss (MBL), and tooth loss (TL) for teeth involved in an alveolar process fracture and to identify...

  17. Quantum fields and Poisson processes. Pt. 2. Interaction of boson-boson and boson-fermion fields with a cut-off

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, J. (Paris-7 Univ., 75 (France). Lab. de Physique Theorique et Mathematique); Gaveau, B.; Rideau, G. (Paris-6 Univ., 75 (France). Dept. de Mathematiques)

    1985-05-01

    Quantum field evolutions are written as expectation values with respect to Poisson processes in two simple models; interaction of two boson fields (with conservation of the number of particles in one field) and interaction of a boson with a fermion field. The introduction of a cutt-off ensures that the expectation values are well-defined.

  18. High-Yield Solvothermal Formation of Magnetic CoPt Alloy Nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zongtao [ORNL; Blom, Douglas Allen [ORNL; Gai, Zheng [ORNL; Thompson, James R [ORNL; Shen, Jian [ORNL; Dai, Sheng [ORNL

    2003-01-01

    One-dimensional (1D) magnetic nanomaterials have attracted much attention recently because of their applications in magnetic recording and spintronics. Nevertheless, it remains a challenge to prepare free-standing magnetic nanowires in high yield. This Communication reports the successful high-yield synthesis of an interesting 1D ferromagnetic CoPt alloy by direct decomposition of platinum acetylacetonate and cobalt carbonyl compound in ethylenediamine solvent through a solvothermal reaction. The CoPt alloy nanowires obtained have a tunable diameter of 10-50 nm and a length along the longitudinal axis of up to several microns, depending on crystallization temperature and reaction time. A unique formation mechanism involving coarsening and ripening under solvothermal conditions was discovered. This research opens new opportunities in synthesizing nanomaterials through low-temperature solvothermal processes.

  19. Quantitative Prediction of Surface Segregation in Bimetallic Pt-MAlloy Nanoparticles (M=Ni, Re, Mo)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guofeng; Van Hove, Michel A.; Ross, Phil N.; Baskes,Michael I.

    2005-06-20

    This review addresses the issue of surface segregation inbimetallic alloy nanoparticles, which are relevant to heterogeneouscatalysis, in particular for electro-catalysts of fuel cells. We describeand discuss a theoretical approach to predicting surface segregation insuch nanoparticles by using the Modified Embedded Atom Method and MonteCarlo simulations. In this manner it is possible to systematicallyexplore the behavior of such nanoparticles as a function of componentmetals, composition, and particle size, among other variables. We choseto compare Pt75Ni25, Pt75Re25, and Pt80Mo20 alloys as example systems forthis discussion, due to the importance of Pt in catalytic processes andits high-cost. It is assumed that the equilibrium nanoparticles of thesealloys have a cubo-octahedral shape, the face-centered cubic lattice, andsizes ranging from 2.5 nm to 5.0 nm. By investigating the segregation ofPt atoms to the surfaces of the nanoparticles, we draw the followingconclusions from our simulations at T= 600 K. (1) Pt75Ni25 nanoparticlesform a surface-sandwich structure in which the Pt atoms are stronglyenriched in the outermost and third layers while the Ni atoms areenriched in the second layer. In particular, a nearly pure Pt outermostsurface layer can be achieved in those nanoparticles. (2) EquilibriumPt75Re25 nanoparticles adopt a core-shell structure: a nearly pure Ptshell surrounding a more uniform Pt-Re core. (3) In Pt80Mo20nanoparticles, the facets are fully occupied by Pt atoms, the Mo atomsonly appear at the edges and vertices, and the Pt and Mo atoms arrangethemselves in an alternating sequence along the edges and vertices. Oursimulations quantitatively agree with previous experimental andtheoretical results for the extended surfaces of Pt-Ni, Pt-Re, and Pt-Moalloys. We further discuss the reasons for the different types of surfacesegregation found in the different alloys, and some of theirimplications.

  20. Observation and elimination of broken symmetry in L1{sub 0} FePt nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Quarterman, P.; Wang, Hao; Qiu, Jiao-Ming; Ma, Bin; Liu, Xiaoqi; Wang, Jian-Ping, E-mail: jpwang@umn.edu [Department of Electrical and Computer Engineering and the Center for Micromagnetics and Information Technologies (MINT), University of Minnesota, Minnesota 55455 (United States); Guo, Honghua [Department of Optical Science and Engineering, Fudan University, Shanghai (China)

    2015-12-07

    An unexplained surface anisotropy effect was observed and confirmed in the magnetization reversal process of both L1{sub 0} phase FePt nanoparticles with octahedral shape and (001) textured L1{sub 0} FePt thin films with island nanostructures. We suggest that the nature of the observed surface effect is caused by broken symmetry on the FePt surface, which results in weakened exchange coupling for surface atoms. Furthermore, we propose, and experimentally demonstrate, a method to repair the broken symmetry by capping the FePt islands with a Pt layer, which could prove invaluable in understanding fundamental limitations of magnetic nanostructures.

  1. Characterization of Phosphate Transporters BdPT4 and BdPT8 in Mycorrhizal and Non-Mychorrhizal Brachypodium distachyon

    DEFF Research Database (Denmark)

    Clausen, Signe Sandbech

    was observed in non-arbusculated cells of AM plants. In arbusculated cells, BdPT8 was detected in the ER while BdPT4 was localized to the plasma membrane and the periarbuscular membrane (PAM) surrounding the arbuscular trunk and thick branches, which further supported a role of both BdPTs in direct Pi uptake......PT proteins were expressed in cells where direct PTs are believed to perform their function, as well as in the vascular tissue. In NM plants, BdPT4 was localized to the plasma membrane whereas BdPT8 accumulated in the endoplasmic reticulum (ER) in the secretory pathway. A similar expression pattern......, and for BdPT4 in AM-mediated Pi uptake as well. In conclusion, the studies suggest that BdPT4 and possibly also BdPT8 are involved in direct uptake as well as in translocation of Pi in B. distachyon. Interestingly, as BdPT4 was additionally localised to the PAM of arbusculated cells, BdPT4 may also...

  2. CLOUD COMPUTING ADOPTION STRATEGIES AT PT TASPEN INDONESIA, Tbk

    Directory of Open Access Journals (Sweden)

    Julirzal Sarmedy

    2014-10-01

    Full Text Available PT. Taspen as Indonesian institution, is responsible for managing social insuranceprograms of civil servants. With branch offices and business partners who are geographicallydispersed throughout Indonesia, information technology is very important to support thebusiness processes. Cloud computing is a model of information technology services that couldpotentially increase the effectiveness and efficiency of PT. Taspen information system. Thisstudy examines the phenomenon exists at PT. Taspen in order to adopt cloud computing inthe information system, by using the framework of Technology-Organization-Environment,Diffusion of Innovation theory, and Partial Least Square method. Organizational factor isthe most dominant for PT. Taspen to adopt cloud computing. Referring to these findings,then a SWOT analysis and TOWS matrix are performed, which in this study recommendsthe implementation of a strategy model of cloud computing services that are private andgradually in process.

  3. Using a Virtual Tablet Machine to Improve Student Understanding of the Complex Processes Involved in Tablet Manufacturing.

    Science.gov (United States)

    Mattsson, Sofia; Sjöström, Hans-Erik; Englund, Claire

    2016-06-25

    Objective. To develop and implement a virtual tablet machine simulation to aid distance students' understanding of the processes involved in tablet production. Design. A tablet simulation was created enabling students to study the effects different parameters have on the properties of the tablet. Once results were generated, students interpreted and explained them on the basis of current theory. Assessment. The simulation was evaluated using written questionnaires and focus group interviews. Students appreciated the exercise and considered it to be motivational. Students commented that they found the simulation, together with the online seminar and the writing of the report, was beneficial for their learning process. Conclusion. According to students' perceptions, the use of the tablet simulation contributed to their understanding of the compaction process.

  4. The level of toxic and essential trace elements in hair of petrochemical workers involved in different technological processes.

    Science.gov (United States)

    Skalny, Anatoly V; Kaminskaya, Galina A; Krekesheva, Tatyana I; Abikenova, Sholpan K; Skalnaya, Margarita G; Berezkina, Elena S; Grabeklis, Andrei R; Tinkov, Alexey A

    2017-02-01

    The objective of the investigation is comparative analysis of hair trace element content in workers of different departments of petrochemical plant. A total of 75 men working in office (engineers), and departments 1 (D1), 3 (D3), and 4 (D4) of the petrochemical plant, as well as occupationally non-exposed persons, were examined. Hair trace element levels were analyzed using inductively coupled plasma mass spectrometry. The office workers were characterized by the highest hair As, Hg, Sn, I, and Si content as compared to the workers of other departments, whereas the level of those elements did not differ significantly from the control values. It is notable that hair Be levels in all employees of petrochemical plant were significantly lower, whereas Se content was significantly higher than that in unexposed controls. Hair toxic trace element content in workers directly involved in industrial processes did not differ significantly or was lower than that in the control group. At the same time, the highest levels of essential trace elements (Cr, Fe, and I) were observed in employees working in primary oil refining (D1). Hair levels of Co, I, and Li were maximal in persons of sulfur and bitumen-producing division (D4). The lowest levels of both essential and toxic trace elements in hair were detected in employees involved in production of liquefied gas, kerosene, and diesel fuel (D3). The obtained data demonstrate that involvement in different technological processes in petrochemical complex differentially affect hair trace element content in workers.

  5. Semantics is crucial for the right-hemisphere involvement in metaphor processing: evidence from mouth asymmetry during speaking.

    Science.gov (United States)

    Argyriou, Paraskevi; Byfield, Sarah; Kita, Sotaro

    2015-01-01

    Research on the neural basis of metaphor provides contradicting evidence about the role of right and left hemispheres. We used the mouth-opening asymmetry technique to investigate the relative involvement of the two hemispheres whilst right-handed healthy male participants explained the meaning of English phrases. This technique is based on the contralateral cortical control of the facial musculature and reflects the relative hemispheric involvement during different cognitive tasks. In particular, right-handers show a right-sided mouth asymmetry (right side of the mouth opens wider than the left) during linguistic tasks, thus reflecting the left-hemisphere specialization for language. In the current study, we compared the right-sided mouth asymmetry during metaphor explanation (e.g., explain the meaning of the phrase "to spin a yarn") and concrete explanation (e.g., explain the meaning of the phrase "to spin a golf ball") and during the production of content and function words. The expected right-sided mouth asymmetry reduced during metaphorical compared to concrete explanations suggesting the relative right-hemispheric involvement for metaphor processing. Crucially, this right-sided mouth asymmetry reduction was particularly pronounced for the production of content words. Thus, we concluded that semantics is crucial to the right-hemispheric involvement for metaphorical speech production.

  6. Design criteria for stable Pt/C fuel cell catalysts.

    Science.gov (United States)

    Meier, Josef C; Galeano, Carolina; Katsounaros, Ioannis; Witte, Jonathon; Bongard, Hans J; Topalov, Angel A; Baldizzone, Claudio; Mezzavilla, Stefano; Schüth, Ferdi; Mayrhofer, Karl J J

    2014-01-01

    Platinum and Pt alloy nanoparticles supported on carbon are the state of the art electrocatalysts in proton exchange membrane fuel cells. To develop a better understanding on how material design can influence the degradation processes on the nanoscale, three specific Pt/C catalysts with different structural characteristics were investigated in depth: a conventional Pt/Vulcan catalyst with a particle size of 3-4 nm and two Pt@HGS catalysts with different particle size, 1-2 nm and 3-4 nm. Specifically, Pt@HGS corresponds to platinum nanoparticles incorporated and confined within the pore structure of the nanostructured carbon support, i.e., hollow graphitic spheres (HGS). All three materials are characterized by the same platinum loading, so that the differences in their performance can be correlated to the structural characteristics of each material. The comparison of the activity and stability behavior of the three catalysts, as obtained from thin film rotating disk electrode measurements and identical location electron microscopy, is also extended to commercial materials and used as a basis for a discussion of general fuel cell catalyst design principles. Namely, the effects of particle size, inter-particle distance, certain support characteristics and thermal treatment on the catalyst performance and in particular the catalyst stability are evaluated. Based on our results, a set of design criteria for more stable and active Pt/C and Pt-alloy/C materials is suggested.

  7. Design criteria for stable Pt/C fuel cell catalysts

    Directory of Open Access Journals (Sweden)

    Josef C. Meier

    2014-01-01

    Full Text Available Platinum and Pt alloy nanoparticles supported on carbon are the state of the art electrocatalysts in proton exchange membrane fuel cells. To develop a better understanding on how material design can influence the degradation processes on the nanoscale, three specific Pt/C catalysts with different structural characteristics were investigated in depth: a conventional Pt/Vulcan catalyst with a particle size of 3–4 nm and two Pt@HGS catalysts with different particle size, 1–2 nm and 3–4 nm. Specifically, Pt@HGS corresponds to platinum nanoparticles incorporated and confined within the pore structure of the nanostructured carbon support, i.e., hollow graphitic spheres (HGS. All three materials are characterized by the same platinum loading, so that the differences in their performance can be correlated to the structural characteristics of each material. The comparison of the activity and stability behavior of the three catalysts, as obtained from thin film rotating disk electrode measurements and identical location electron microscopy, is also extended to commercial materials and used as a basis for a discussion of general fuel cell catalyst design principles. Namely, the effects of particle size, inter-particle distance, certain support characteristics and thermal treatment on the catalyst performance and in particular the catalyst stability are evaluated. Based on our results, a set of design criteria for more stable and active Pt/C and Pt-alloy/C materials is suggested.

  8. Ag/Au/Pt trimetallic nanoparticles with defects: preparation, characterization, and electrocatalytic activity in methanol oxidation

    Science.gov (United States)

    Thongthai, Kontee; Pakawanit, Phakkhananan; Chanlek, Narong; Kim, Jun-Hyun; Ananta, Supon; Srisombat, Laongnuan

    2017-09-01

    Two series of Ag x /Au/Pt y trimetallic nanoparticles (Ag x Au1Pt2 with x ranging from 1-5 and Ag4Au1Pt y with y ranging from 1-3) were prepared by a sequential chemical reduction method that involved the deposition of Pt on preformed Ag/Au core-shell particles by systematically controlling the amount of Ag, Au, and Pt metal precursor solutions. The structural changes (the diameters and increased surface roughness from the defective features) and absorption patterns (the significant reduction of the peak intensities) of the nanoparticles examined with TEM and UV-vis spectroscopy indicated the selective incorporation of Pt on the Ag/Au nanoparticles regardless of their compositions. In addition, a combination of WDX, XRD, and XPS analyses quantitatively and qualitatively confirmed the successful formation of the Ag x Au1Pt2 and Ag4Au1Pt y trimetallic nanoparticles. Subsequently, these series of nanoparticles were deposited on multi-wall carbon nanotubes (MWCNTs) to evaluate their electrocatalytic property in the methanol oxidation reaction (MOR) as a function of their metal compositions. The results showed that the electrocatalytic activities of all Ag4/Au1/Pt y systems were higher than those of typical Pt on the MWCNTs. In particular, the Ag4Au1Pt2 nanoparticles exhibited the highest electrocatalytic property for the MOR, suggesting the importance of the proper combination of metal constituents and structures to regulate the activity in electrocatalytic systems.

  9. Atomic-Scale Mechanism for Hydrogenation of o-Cresol on Pt Catalysis

    Science.gov (United States)

    Li, Yaping; Liu, Zhimin; Xue, Wenhua; Crossley, Steven; Jentoft, Friederike; Wang, Sanwu

    Biofuels derived from lignocellulosic biomass have received significant attention lately due to increasing environmental concerns. With first-principles density-functional theory and ab initio molecular dynamic simulations, we investigated the atomic-scale mechanism of o-cresol hydrogenation on the Pt(111) surface. The formation of 2-methyl-cyclohexanone (the intermediate product) was found to involve two steps. The first step is the dehydrogenation, that is, the H atom in the hydroxyl group moves to the Pt surface. The second step is the hydrogenation, that is, the H atoms on Pt react with the carbon atoms in the aromatic ring. The first step involves a smaller barrier, suggesting that dehydrogenation occurs first, followed by hydrogenation of the ring. In particular, tautomerization is found to occur via a two-step process over the catalyst. On the other hand, 2-methyl-cyclohexanol (the final product) is produced through two paths. One is direct hydrogenation of the aromatic ring. Another pathway includes partial hydrogenation of the ring, dehydrogenation of -OH group, finally hydrogenation of remaining C atoms and the O atom. Our theoretical results agree well with the experimental observations. Supported by DOE (DE-SC0004600). This research used the supercomputer resources of NERSC, XSEDE, TACC.

  10. Involving Older Adults in the Technology Design Process: A Case Study on Mobility and Wellbeing in the Built Environment.

    Science.gov (United States)

    Swallow, David; Petrie, Helen; Power, Christopher; Lewis, Andrew; Edwards, Alistair D N

    2016-01-01

    Older adults benefit from unstructured, lifestyle-based activity that can be carried out in people's houses, neighbourhoods, and the built environment. Technological solutions may support physical activity and encourage wellbeing. To ensure such technology is suitable for, and usable by, older adults, it is crucial they are involved in all stages of design. Participatory design methodologies facilitate collaboration and engagement with potential users. We examine the suitability of participatory design for collaborating and engaging with older adults. Participatory design workshops were conducted with 33 older adults in the UK with the aim of designing mobile applications to support and promote physical activity and wellbeing in the built environment. As well as summarising the outcome of these workshops, the paper outlines several methodological issues relating to the suitability of participatory design for involving older adults in the technology design process.

  11. Perancangan Sistem Informasi Administrasi pada Perusahaan Jasa Penyaluran Tenaga Kerja ke Luar Negeri: Studi Kasus pada PT XYZ

    Directory of Open Access Journals (Sweden)

    Tanty Oktavia

    2011-12-01

    Full Text Available Running the business process of labor supply is not easy since it involves several parties, and n supported by elements of the documents obtained from internal and external parties. PT XYZ as a company dealing with labor supply service to foreign countries has not had any competent information systems in supporting its business processes. Therefore, this research is expected to produce a draft of information system and database applications that can support the administrative activities of labor supply of the company. The research used both analysis and design methods. Analytical method includes survey of the current system done by observation, interviews, identification of the information needs of the survey results and identification of system requirements. The design method consists of designing a model system using UML notation, designing databases and user interfaces for supporting applications. The information system applications resulted in this research can be a competitive advantage in marketing their employment services and improve business processes of PT XYZ.

  12. Brain network involved in visual processing of movement stimuli used in upper limb robotic training: an fMRI study.

    Science.gov (United States)

    Nocchi, Federico; Gazzellini, Simone; Grisolia, Carmela; Petrarca, Maurizio; Cannatà, Vittorio; Cappa, Paolo; D'Alessio, Tommaso; Castelli, Enrico

    2012-07-24

    The potential of robot-mediated therapy and virtual reality in neurorehabilitation is becoming of increasing importance. However, there is limited information, using neuroimaging, on the neural networks involved in training with these technologies. This study was intended to detect the brain network involved in the visual processing of movement during robotic training. The main aim was to investigate the existence of a common cerebral network able to assimilate biological (human upper limb) and non-biological (abstract object) movements, hence testing the suitability of the visual non-biological feedback provided by the InMotion2 Robot. A visual functional Magnetic Resonance Imaging (fMRI) task was administered to 22 healthy subjects. The task required observation and retrieval of motor gestures and of the visual feedback used in robotic training. Functional activations of both biological and non-biological movements were examined to identify areas activated in both conditions, along with differential activity in upper limb vs. abstract object trials. Control of response was also tested by administering trials with congruent and incongruent reaching movements. The observation of upper limb and abstract object movements elicited similar patterns of activations according to a caudo-rostral pathway for the visual processing of movements (including specific areas of the occipital, temporal, parietal, and frontal lobes). Similarly, overlapping activations were found for the subsequent retrieval of the observed movement. Furthermore, activations of frontal cortical areas were associated with congruent trials more than with the incongruent ones. This study identified the neural pathway associated with visual processing of movement stimuli used in upper limb robot-mediated training and investigated the brain's ability to assimilate abstract object movements with human motor gestures. In both conditions, activations were elicited in cerebral areas involved in visual

  13. Brain network involved in visual processing of movement stimuli used in upper limb robotic training: an fMRI study

    Directory of Open Access Journals (Sweden)

    Nocchi Federico

    2012-07-01

    Full Text Available Abstract Background The potential of robot-mediated therapy and virtual reality in neurorehabilitation is becoming of increasing importance. However, there is limited information, using neuroimaging, on the neural networks involved in training with these technologies. This study was intended to detect the brain network involved in the visual processing of movement during robotic training. The main aim was to investigate the existence of a common cerebral network able to assimilate biological (human upper limb and non-biological (abstract object movements, hence testing the suitability of the visual non-biological feedback provided by the InMotion2 Robot. Methods A visual functional Magnetic Resonance Imaging (fMRI task was administered to 22 healthy subjects. The task required observation and retrieval of motor gestures and of the visual feedback used in robotic training. Functional activations of both biological and non-biological movements were examined to identify areas activated in both conditions, along with differential activity in upper limb vs. abstract object trials. Control of response was also tested by administering trials with congruent and incongruent reaching movements. Results The observation of upper limb and abstract object movements elicited similar patterns of activations according to a caudo-rostral pathway for the visual processing of movements (including specific areas of the occipital, temporal, parietal, and frontal lobes. Similarly, overlapping activations were found for the subsequent retrieval of the observed movement. Furthermore, activations of frontal cortical areas were associated with congruent trials more than with the incongruent ones. Conclusions This study identified the neural pathway associated with visual processing of movement stimuli used in upper limb robot-mediated training and investigated the brain’s ability to assimilate abstract object movements with human motor gestures. In both conditions

  14. Electric field mediated non-volatile tuning magnetism in CoPt/PMN-PT heterostructure for magnetoelectric memory devices

    Science.gov (United States)

    Yang, Y. T.; Li, J.; Peng, X. L.; Wang, X. Q.; Wang, D. H.; Cao, Q. Q.; Du, Y. W.

    2016-02-01

    We report a power efficient non-volatile magnetoelectric memory in the CoPt/(011)PMN-PT heterostructure. Two reversible and stable electric field induced coercivity states (i.e., high-HC or low-HC) are obtained due to the strain mediated converse magnetoelectric effect. The reading process of the different coercive field information written by electric fields is demonstrated by using a magnetoresistance read head. This result shows good prospects in the application of novel multiferroic devices.

  15. Dielectric properties of (110) oriented PbZrO3 and La-modified PbZrO3 thin films grown by sol-gel process on Pt(111)/Ti /SiO2/Si substrate

    Science.gov (United States)

    Parui, Jayanta; Krupanidhi, S. B.

    2006-08-01

    Highly (110) preferred orientated antiferroelectric PbZrO3 (PZ) and La-modified PZ thin films have been fabricated on Pt /Ti/SiO2/Si substrates using sol-gel process. Dielectric properties, electric field induced ferroelectric polarization, and the temperature dependence of the dielectric response have been explored as a function of composition. The Tc has been observed to decrease by ˜ 17°C per 1mol% of La doping. Double hysteresis loops were seen with zero remnant polarization and with coercive fields in between 176 and 193kV/cm at 80°C for antiferroelectric to ferroelectric phase transformation. These slim loops have been explained by the high orientation of the films along the polar direction of the antiparallel dipoles of a tetragonal primitive cell and by the strong electrostatic interaction between La ions and oxygen ions in an ABO3 perovskite unit cell. High quality films exhibited very low loss factor less than 0.015 at room temperature and pure PZ; 1 and 2mol% La doped PZs have shown the room temperature dielectric constant of 135, 219, and 142 at the frequency of 10kHz. The passive layer effects in these films have been explained by Curie constants and Curie temperatures. The ac conductivity and the corresponding Arrhenius plots have been shown and explained in terms of doping effect and electrode resistance.

  16. Pt(IV) complexes as prodrugs for cisplatin.

    Science.gov (United States)

    Shi, Yi; Liu, Shu-An; Kerwood, Deborah J; Goodisman, Jerry; Dabrowiak, James C

    2012-02-01

    The antitumor effects of platinum(IV) complexes, considered prodrugs for cisplatin, are believed to be due to biological reduction of Pt(IV) to Pt(II), with the reduction products binding to DNA and other cellular targets. In this work we used pBR322 DNA to capture the products of reduction of oxoplatin, c,t,c-[PtCl(2)(OH)(2)(NH(3))(2)], 3, and a carboxylate-modified analog, c,t,c-[PtCl(2)(OH)(O(2)CCH(2)CH(2)CO(2)H)(NH(3))(2)], 4, by ascorbic acid (AsA) or glutathione (GSH). Since carbonate plays a significant role in the speciation of platinum complexes in solution, we also investigated the effects of carbonate on the reduction/DNA-binding process. In pH 7.4 buffer in the absence of carbonate, both 3 and 4 are reduced by AsA to cisplatin (confirmed using ((195))Pt NMR), which binds to and unwinds closed circular DNA in a manner consistent with the formation of the well-known 1, 2 intrastrand DNA crosslink. However, when GSH is used as the reducing agent for 3 and 4, ((195))Pt NMR shows that cisplatin is not produced in the reaction medium. Although the Pt(II) products bind to closed circular DNA, their effect on the mobility of Form I DNA is different from that produced by cisplatin. When physiological carbonate is present in the reduction medium, ((13))C NMR shows that Pt(II) carbonato complexes form which block or impede platinum binding to DNA. The results of the study vis-à-vis the ability of the Pt(IV) complexes to act as prodrugs for cisplatin are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Perpendicular coercivity enhancement of CoPt/TiN films by nitrogen incorporation during deposition

    Science.gov (United States)

    An, Hongyu; Wang, Jian; Szivos, Janos; Harumoto, Takashi; Sannomiya, Takumi; Muraishi, Shinji; Safran, Gyorgy; Nakamura, Yoshio; Shi, Ji

    2015-11-01

    The effect of N incorporation on the structure and magnetic properties of CoPt thin films deposited on glass substrates with TiN seed layers has been investigated. During the deposition of CoPt, introducing 20% N2 into Ar atmosphere promotes the (001) texture and enhances the perpendicular coercivity of CoPt film compared with the film deposited in pure Ar and post-annealed under the same conditions. From the in situ x-ray diffraction results, it is confirmed that N incorporation expands the lattice parameter of CoPt, which favors the epitaxial growth of CoPt on TiN. During the post-annealing process, N releases from CoPt film and promotes the L10 ordering transformation of CoPt.

  18. Perpendicular coercivity enhancement of CoPt/TiN films by nitrogen incorporation during deposition

    Energy Technology Data Exchange (ETDEWEB)

    An, Hongyu; Harumoto, Takashi; Sannomiya, Takumi; Muraishi, Shinji; Nakamura, Yoshio; Shi, Ji, E-mail: Shi.j.aa@m.titech.ac.jp [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552 (Japan); Wang, Jian [National Institute for Materials Science (NIMS), Sengen 1-2-1, Tsukuba, Ibaraki 305-0047 (Japan); Szivos, Janos; Safran, Gyorgy [Hungarian Academy of Sciences, Research Institute for Technical Physics and Materials Science, H-1121 Budapest, Konkoly-Thege ut 29-33 (Hungary)

    2015-11-28

    The effect of N incorporation on the structure and magnetic properties of CoPt thin films deposited on glass substrates with TiN seed layers has been investigated. During the deposition of CoPt, introducing 20% N{sub 2} into Ar atmosphere promotes the (001) texture and enhances the perpendicular coercivity of CoPt film compared with the film deposited in pure Ar and post-annealed under the same conditions. From the in situ x-ray diffraction results, it is confirmed that N incorporation expands the lattice parameter of CoPt, which favors the epitaxial growth of CoPt on TiN. During the post-annealing process, N releases from CoPt film and promotes the L1{sub 0} ordering transformation of CoPt.

  19. Chemical and mineralogical data and processing methods management system prototype with application to study of the North Caucasus Blybsky Metamorphic Complexes metamorphism PT-condition

    Science.gov (United States)

    Ivanov, Stanislav; Kamzolkin, Vladimir; Konilov, Aleksandr; Aleshin, Igor

    2014-05-01

    There are many various methods of assessing the conditions of rocks formation based on determining the composition of the constituent minerals. Our objective was to create a universal tool for processing mineral's chemical analysis results and solving geothermobarometry problems by creating a database of existing sensors and providing a user-friendly standard interface. Similar computer assisted tools are based upon large collection of sensors (geothermometers and geobarometers) are known, for example, the project TPF (Konilov A.N., 1999) - text-based sensor collection tool written in PASCAL. The application contained more than 350 different sensors and has been used widely in petrochemical studies (see A.N. Konilov , A.A. Grafchikov, V.I. Fonarev 2010 for review). Our prototype uses the TPF project concept and is designed with modern application development techniques, which allows better flexibility. Main components of the designed system are 3 connected datasets: sensors collection (geothermometers, geobarometers, oxygen geobarometers, etc.), petrochemical data and modeling results. All data is maintained by special management and visualization tools and resides in sql database. System utilities allow user to import and export data in various file formats, edit records and plot graphs. Sensors database contains up to date collections of known methods. New sensors may be added by user. Measured database should be filled in by researcher. User friendly interface allows access to all available data and sensors, automates routine work, reduces the risk of common user mistakes and simplifies information exchange between research groups. We use prototype to evaluate peak pressure during the formation of garnet-amphibolite apoeclogites, gneisses and schists Blybsky metamorphic complex of the Front Range of the Northern Caucasus. In particular, our estimation of formation pressure range (18 ± 4 kbar) agrees on independent research results. The reported study was

  20. Pt nanoparticles embedded on reduced graphite oxide with excellent electrocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Saravanan, Gengan, E-mail: saravanan3che@gmail.com [Central University of Tamil Nadu, Department of Chemistry, Thiruvarur, 610101 (India); Mohan, Subramanian, E-mail: sanjnamohan@yahoo.com [EMFT Division, CSIR-Central Electrochemical Research Institute, Tamilnadu, Karaikudi 630 006 (India)

    2016-11-15

    Graphical abstract: RGO/Nano Pt: This study explore the electrocatalytic oxidation performance of reduced graphite oxide (RGO) anchored with nano Pt. This graphene composite reveal superior electrooxidation performance that is associated with the flexible RGO matrix and the uniform distribution of Pt particles, which enhances surface area, fast electron transfer, uniform particle size distribution; consequently, the RGO matrix provides more stability to Pt particles during electrooxidation process. Display Omitted - Highlights: • Greener electrochemical method applied to prepare well-dispersed Pt-rGO. • Pt-rGO large surface area excellent charge transfer better catalytic activity. • Low-cost highly efficient carbon-based electrodes for direct formic acid fuel cell. • rGO an excellent support to anchor Pt nanoparticles on its surface. • Pt-rGO distinctly enhanced current density towards formic acid electrooxidation. - Abstract: Economically viable electrochemical approach has been developed for the synthesis of Pt nanoparticles through electrodeposition technique on the surface of Reduced Graphite Oxide (RGO). Pt nanoparticles embedded Reduced Graphite Oxide on Glassy Carbon Electrode are employed (Pt-rGO/GCE) for electrooxidation of formic acid. Scanning Electron Microscopy (SEM) image and Transmission Electron Microscopy (TEM) image shows that reduced graphite oxide act as an excellent support to anchor the Pt nanoparticles. Cyclic voltammetry results confirmed that Pt-rGO/GCE enhanced current density as many folds than that of bare platinum electrode for electrooxidation of formic acid. X-ray diffraction (XRD) patterns for Pt-graphene composites illustrate that peaks at 69.15 and 23° for Pt (220) and graphene carbon (002) respectively. {sup 13}C NMR spectrum of the electrochemically reduced graphite oxide resonance contains only one peak at 133 ppm which retains graphitic sp{sup 2} carbon and does not contain any oxygenated carbon and the carbonyl

  1. The Involvement of Hemocyte Prophenoloxidase in the Shell-Hardening Process of the Blue Crab, Callinectes sapidus.

    Directory of Open Access Journals (Sweden)

    Javier V Alvarez

    Full Text Available Cuticular structures of arthropods undergo dramatic molt-related changes from being soft to becoming hard. The shell-hardening process of decapod crustaceans includes sclerotization and mineralization. Hemocyte PPO plays a central role in melanization and sclerotization particularly in wound healing in crustaceans. However, little is known about its role in the crustacean initial shell-hardening process. The earlier findings of the aggregation of heavily granulated hemocytes beneath the hypodermis during ecdysis imply that the hemocytes may be involved in the shell-hardening process. In order to determine if hemocytes and hemocyte PPO have a role in the shell-hardening of crustaceans, a knockdown study using specific CasPPO-hemo-dsRNA was carried out with juvenile blue crabs, Callinectes sapidus. Multiple injections of CasPPO-hemo-dsRNA reduce specifically the levels of CasPPO-hemo expression by 57% and PO activity by 54% in hemocyte lysate at the postmolt, while they have no effect on the total hemocyte numbers. Immunocytochemistry and flow cytometry analysis using a specific antiserum generated against CasPPO show granulocytes, semigranulocytes and hyaline cells as the cellular sources for PPO at the postmolt. Interestingly, the type of hemocytes, as the cellular sources of PPO, varies by molt stage. The granulocytes always contain PPO throughout the molt cycle. However, semigranulocytes and hyaline cells become CasPPO immune-positive only at early premolt and postmolt, indicating that PPO expression in these cells may be involved in the shell-hardening process of C. sapidus.

  2. The Involvement of Hemocyte Prophenoloxidase in the Shell-Hardening Process of the Blue Crab, Callinectes sapidus.

    Science.gov (United States)

    Alvarez, Javier V; Chung, J Sook

    2015-01-01

    Cuticular structures of arthropods undergo dramatic molt-related changes from being soft to becoming hard. The shell-hardening process of decapod crustaceans includes sclerotization and mineralization. Hemocyte PPO plays a central role in melanization and sclerotization particularly in wound healing in crustaceans. However, little is known about its role in the crustacean initial shell-hardening process. The earlier findings of the aggregation of heavily granulated hemocytes beneath the hypodermis during ecdysis imply that the hemocytes may be involved in the shell-hardening process. In order to determine if hemocytes and hemocyte PPO have a role in the shell-hardening of crustaceans, a knockdown study using specific CasPPO-hemo-dsRNA was carried out with juvenile blue crabs, Callinectes sapidus. Multiple injections of CasPPO-hemo-dsRNA reduce specifically the levels of CasPPO-hemo expression by 57% and PO activity by 54% in hemocyte lysate at the postmolt, while they have no effect on the total hemocyte numbers. Immunocytochemistry and flow cytometry analysis using a specific antiserum generated against CasPPO show granulocytes, semigranulocytes and hyaline cells as the cellular sources for PPO at the postmolt. Interestingly, the type of hemocytes, as the cellular sources of PPO, varies by molt stage. The granulocytes always contain PPO throughout the molt cycle. However, semigranulocytes and hyaline cells become CasPPO immune-positive only at early premolt and postmolt, indicating that PPO expression in these cells may be involved in the shell-hardening process of C. sapidus.

  3. Oxidation of atrazine in aqueous media by solar- enhanced Fenton-like process involving persulfate and ferrous ion.

    Science.gov (United States)

    Khandarkhaeva, Marina; Batoeva, Agniya; Aseev, Denis; Sizykh, Marina; Tsydenova, Oyuna

    2017-03-01

    The oxidation of s-triazines (using atrazine (ATZ) as a model compound) by a solar-enhanced Fenton-like process involving persulfate and ferrous ion was studied. A flow-through tubular photoreactor was employed for the experiments. The solar-enhanced oxidative system involving ferrous ion and persulfate (Solar/S2O8(2-)/Fe(2+)) showed the highest ATZ degradation efficiency when compared with other treatments (unactivated S2O8(2-), Solar - sunlight only, S2O8(2-)/Fe(2+), Solar/S2O8(2-)). Complete degradation of ATZ and 20% reduction in total organic carbon (TOC) content were observed after 30min of the treatment. The in situ generated (•)ОН and SO4(-•) radicals were shown to be involved in ATZ oxidation using the radical scavengers methanol and tert-butyl alcohol. Furthermore, iron compounds were shown to act not only as catalysts but also as photo-sensitizers, as the introduction of ferrous ion into the reaction mixture led to an increased absorbance of the solution and expansion of the absorption spectrum into the longer wavelength spectral region. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Structure of Pt/C and PtRu/C catalytic layers prepared by plasma sputtering and electric performance in direct methanol fuel cells (DMFC)

    Energy Technology Data Exchange (ETDEWEB)

    Caillard, A.; Brault, P.; Mathias, J. [Groupe de Recherche sur l' Energetique des Milieux Ionises, UMR6606 Universite d' Orleans, CNRS, Polytech' Orleans BP6744, F-45067 Orleans Cedex 2 (France); Coutanceau, C.; Leger, J.-M. [Laboratoire de Catalyse en Chimie Organique, UMR6503 Universite de Poitiers, CNRS, F-86022 Poitiers (France)

    2006-11-08

    Plasma sputtering process was used to deposit Pt and PtRu on conductive carbon diffusion layer. Low metal loading catalysts for methanol electrooxidation were prepared and characterized by TEM and XRD. The main result is that codeposition of Pt and Ru leads to alloy phase, whereas multi-layers deposition leads to no-alloyed structure. The electrochemical performance of sputtered Pt/C electrodes was compared with that of standard electrodes, and was found lower. However, the specific activity was much higher, indicating that the catalyst utilization efficiency was higher than that obtained with a standard electrode. Then, different bimetallic PtRu/C electrodes were prepared by plasma sputtering, leading to different catalyst structures (Pt and Ru multilayer deposition or simultaneous deposition of Pt and Ru) and composition (from 100:0 to 50:50 Pt/Ru atomic ratios). At last, the different PtRu electrodes were compared in term of DMFC electrical performance. The best efficiency of the DMFC was reached when both metals Pt and Ru are simultaneously deposited (alloyed) with a ruthenium atomic ratio of 30% or 40 % Ru depending of the working potentials of the cell. (author)

  5. Development of a ReaxFF potential for Pt-O systems describing the energetics and dynamics of Pt-oxide formation.

    Science.gov (United States)

    Fantauzzi, Donato; Bandlow, Jochen; Sabo, Lehel; Mueller, Jonathan E; van Duin, Adri C T; Jacob, Timo

    2014-11-14

    ReaxFF force field parameters describing Pt-Pt and Pt-O interactions have been developed and tested. The Pt-Pt parameters are shown to accurately account for the chemical nature, atomic structures and other materials properties of bulk platinum phases, low and high-index platinum surfaces and nanoclusters. The Pt-O parameters reliably describe bulk platinum oxides, as well as oxygen adsorption and oxide formation on Pt(111) terraces and the {111} and {100} steps connecting them. Good agreement between the force field and both density functional theory (DFT) calculations and experimental observations is demonstrated in the relative surface free energies of high symmetry Pt-O surface phases as a function of the oxygen chemical potential, making ReaxFF an ideal tool for more detailed investigations of more complex Pt-O surface structures. Validation for its application to studies of the kinetics and dynamics of surface oxide formation in the context of either molecular dynamics (MD) or Monte Carlo simulations are provided in part by a two-part investigation of oxygen diffusion on Pt(111), in which nudged elastic band (NEB) calculations and MD simulations are used to characterize diffusion processes and to determine the relevant diffusion coefficients and barriers. Finally, the power of the ReaxFF reactive force field approach in addressing surface structures well beyond the reach of routine DFT calculations is exhibited in a brief proof-of-concept study of oxygen adsorbate displacement within ordered overlayers.

  6. Pt/C Fuel Cell Catalyst Degradation

    DEFF Research Database (Denmark)

    Zana, Alessandro

    This thesis investigates the degradation behavior of Pt/C catalysts under simulated automotive conditions. By using the “tool box” synthesis method the Pt loading has been changed from low to high Pt loadings, therefore permitting to study the role of Pt on the degradation of high surface area (H...

  7. Pt/C Fuel Cell Catalyst Degradation

    DEFF Research Database (Denmark)

    Zana, Alessandro

    This thesis investigates the degradation behavior of Pt/C catalysts under simulated automotive conditions. By using the “tool box” synthesis method the Pt loading has been changed from low to high Pt loadings, therefore permitting to study the role of Pt on the degradation of high surface area (H...

  8. The Involvement of Centralized and Distributed Processes in Sub-second Time Interval Adaptation: An ERP Investigation of Apparent Motion.

    Science.gov (United States)

    Kaya, Utku; Yildirim, Fazilet Zeynep; Kafaligonul, Hulusi

    2017-09-09

    Accumulating evidence suggests that the timing of brief stationary sounds affects visual motion perception. Recent studies have shown that auditory time interval can alter apparent motion perception not only through concurrent stimulation but also through brief adaptation. The adaptation aftereffects for auditory time intervals were found to be similar to those for visual time intervals, suggesting the involvement of a central timing mechanism. To understand the nature of cortical processes underlying such aftereffects, we adapted observers to different time intervals by using either brief sounds or visual flashes and examined the evoked activity to the subsequently presented visual apparent motion. Both auditory and visual time interval adaptation led to significant changes in the ERPs elicited by the apparent motion. However, the changes induced by each modality were in the opposite direction. Also, they mainly occurred in different time windows and clustered over distinct scalp sites. The effects of auditory time interval adaptation were centered over parietal and parieto-central electrodes while the visual adaptation effects were mostly over occipital and parieto-occipitial regions. Moreover, the changes were much more salient when sounds were used during the adaptation phase. Taken together, our findings within the context of visual motion point to auditory dominance in the temporal domain and highlight the distinct nature of the sensory processes involved in auditory and visual time interval adaptation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Strengthening community involvement in grant review: insights from the Community-University Research Partnership (CURES) pilot review process.

    Science.gov (United States)

    Paberzs, Adam; Piechowski, Patricia; Warrick, Debra; Grawi, Carolyn; Choate, Celeste; Sneed, Glenda; Carr, Diane; Lota, Kanchan; Key, Kent; Alexander, Valerie; Ghosh, Pratik; Sampselle, Carolyn

    2014-04-01

    In 2007, the Michigan Institute for Clinical and Health Research (MICHR) at the University of Michigan received a Clinical and Translational Science Award (CTSA). Within MICHR, the Community Engagement (CE) program supports partnership efforts between researchers, practitioners, and community-based organizations in specific focal communities throughout Michigan. A key component of the CE program is the Community Engagement Coordinating Council, a group that provides input and guidance on program priorities, strategic planning, and reviews pilot funding proposals for community-academic partnerships. This paper will describe a unique MICHR pilot funding mechanism for Community-University Research Partnerships (CURES) with an emphasis on the ways that community partners are involved in the review process, as well as the benefits, challenges, and insights gained over 5 years of pilot review. There is a growing need for community involvement and expertise in review of funding proposals for community-engaged research at both institutional and federal levels. The CURES pilot review process is one example of an institutional effort to engage community partners in university funding decisions and has demonstrated clear benefit toward accomplishing the aims of the CTSA.

  10. THE TRANSFORMATIONAL PROCESSES INVOLVING MOTOR SKILLS THAT OCCUR UNDER THE INFLUENCE OF BASIC PRELIMINARY TRAINING IN YOUNG HANDBALL PLAYERS

    Directory of Open Access Journals (Sweden)

    Markovic Sasa

    2011-06-01

    Full Text Available The population from which we extracted a sample of 76 subjects consisted of elementary school students in Kursumlija, all male, aged 12-13, who were divided into a sub-sample consisting of 38 young handball players who took part in the training sessions of a school of handball and another sub-sample consisting of 38 non-athletes, who only took part in their regular physical education classes. The aim of the research was to determine the transformation processes involving motor skills, which occur under the influence of basic preliminary training in young handball players. The subject matter of the study was to examine whether a statistically significant increase in the level of motor skills would occur under the influence of physical exercise as part of basic preliminary training in the final as compared to the initial state. Six motor tests which define the dimensions of explosive and repetitive strength were used. The results of the research indicate that significant transformational processes involving the motor skills of young handball players occurred in the final as compared to the initial measuring, under the influence of basic preliminary training.

  11. Integrated downstream processing of lactoperoxidase from milk whey involving aqueous two-phase extraction and ultrasound-assisted ultrafiltration.

    Science.gov (United States)

    Nandini, K E; Rastogi, Navin K

    2011-01-01

    The present work involves the adoption of an integrated approach for the purification of lactoperoxidase from milk whey by coupling aqueous two-phase extraction (ATPE) with ultrasound-assisted ultrafiltration. The effect of system parameters of ATPE such as type of phase system, polyethylene glycol (PEG) molecular mass, system pH, tie line length and phase volume ratio was evaluated so as to obtain differential partitioning of contaminant proteins and lactoperoxidase in top and bottom phases, respectively. PEG 6000-potassium phosphate system was found to be suitable for the maximum activity recovery of lactoperoxidase 150.70% leading to 2.31-fold purity. Further, concentration and purification of enzyme was attempted using ultrafiltration. The activity recovery and purification factor achieved after ultrafiltration were 149.85% and 3.53-fold, respectively. To optimise productivity and cost-effectiveness of integrated process, influence of ultrasound for the enhancement of permeate flux during ultrafiltration was also investigated. Intermittent use of ultrasound along with stirring (2 min acoustic and 2 min stirring) resulted in increased permeate flux from 0.94 to 2.18 l/m(2) h in comparison to the ultrafiltration without ultrasound. The use of ultrasound during ultrafiltration resulted in increase in flux, but there was no significant change in activity recovery and purification factor. The integrated approach involving ATPE and ultrafiltration may prove to be a feasible method for the downstream processing of lactoperoxidase from milk whey.

  12. Single Pt nanowire electrode: preparation, electrochemistry, and electrocatalysis.

    Science.gov (United States)

    Li, Yongxin; Wu, Qingqing; Jiao, Shoufeng; Xu, Chaodi; Wang, Lun

    2013-04-16

    A single Pt nanowire electrode (SPNE) was fabricated through HF etching process from Pt disk nanoelectrode and an underpotential deposition (UPD) redox replacement technique. The electrochemical experiments showed that SPNE had steady-state electrochemical responses at redox species solution and the mass transfer rates were affected by the lengths and radii of SPNEs. The prepared SPNEs were utilized to examine the oxygen-reduction reaction in a KOH solution to explore the feasibility of electrocatalytic activity of single Pt nanowire and the results showed that the electrocatalytic activity of SPNE was dependent on the surface position of single Pt nanowire: the tip end position is more active than the sidewall position. Meanwhile, the electrocatalytic activity of SPNE was related to the radius of nanowire. These observations are not only important to understand the structure-function relationship in single nanowire level but have significant implications for the synthesis and selection of novel catalysts with high efficiency used in electrochemistry, energy, bioanalysis, etc.

  13. Evaluation of Involvement of Children/Adolescents Diagnosed with Cancer in Their Own Assent Process and Treatment

    Directory of Open Access Journals (Sweden)

    Hatice Demir Küreci

    2016-04-01

    Full Text Available In cases of life-threatening diseases such as cancer, physicians’ tendency to reveal the medical truth to the patients can vary depending on each country’s own moral, social and cultural structures as well as countries’ health policies and traditional physician attitudes. Furthermore, the way of informing patients about cancer diagnosis can vary depending on the patient’s characteristics and psychological adaptation methods. The situation is more complicated to when the patients are from children or adolescent age group. Children and adolescents are left out of assent process because of physicians’ and parents’ concerns about cancer and death, their wish to protect the child from these worries and their belief that children are not psychologically powerful enough to deal with this situation. However children and adolescents must be involved in the treatment decision process because it is important to build the physician-patient relationship on mutual trust in order to assure compliance in cancer treatment and cooperation that is required for the treatment. In this article, first of, all the importance of getting approval of children for the treatment will be emphasized. Afterwards attitudes of physicians and parents, who take part in the process as decision makers in telling the truth, will be examined. Following a brief review of approaches regarding our country; the importance of communication in the cancer process and our recommendations will be expressed.

  14. FMRI evidence for the involvement of the procedural memory system in morphological processing of a second language.

    Directory of Open Access Journals (Sweden)

    Christos Pliatsikas

    Full Text Available Behavioural evidence suggests that English regular past tense forms are automatically decomposed into their stem and affix (played  = play+ed based on an implicit linguistic rule, which does not apply to the idiosyncratically formed irregular forms (kept. Additionally, regular, but not irregular inflections, are thought to be processed through the procedural memory system (left inferior frontal gyrus, basal ganglia, cerebellum. It has been suggested that this distinction does not to apply to second language (L2 learners of English; however, this has not been tested at the brain level. This fMRI study used a masked-priming task with regular and irregular prime-target pairs (played-play/kept-keep to investigate morphological processing in native and highly proficient late L2 English speakers. No between-groups differences were revealed. Compared to irregular pairs, regular pairs activated the pars opercularis, bilateral caudate nucleus and the right cerebellum, which are part of the procedural memory network and have been connected with the processing of morphologically complex forms. Our study is the first to provide evidence for native-like involvement of the procedural memory system in processing of regular past tense by late L2 learners of English.

  15. Study on the preparation of Pt nanocapsules

    Science.gov (United States)

    Zhang, Yi-fan; Ji, Zhen; Chen, Ke; Liu, Bo-wen; Jia, Cheng-chang; Yang, Shan-wu

    2017-01-01

    Ag@Pt core-shell nanoparticles (Ag@Pt NPs) were prepared by a co-reduction method. Pt nanocapsules with diameters of less than 10 nm were obtained by an electrochemical method. Cyclic voltammetry (CV) scanning was used to cavitate the Ag@Pt NPs, and the morphology, structure, and cavitation conditions were studied. The results indicate that the effective cavitation conditions to obtain Pt nanoparticles from Ag@Pt NPs are a scanning voltage of 0 to 0.8 V and continuous CV scanning over 2 h. This cavitation method is also applicable for the syntheses of Ir, Ru, and Ru-Pt nanocapsules.

  16. New insights into the effects of alloying Pt with Ni on oxygen reduction reaction mechanisms in acid medium: a first-principles study.

    Science.gov (United States)

    Ou, Li-Hui

    2015-11-01

    The effects of alloying Pt with transition metal Ni on oxygen reduction reaction (ORR) mechanisms was investigated based on a systematic density functional theory (DFT) calculation explored in the present work. New insights into the ORR mechanisms were reported at the atomic level on Pt-segregated Pt3Ni(111). Only one molecular chemisorption state with the end-on OOH configuration was identified through geometry optimization and minimum energy path (MEP) analysis; top-bridge-top configuration as observed on pure Pt(111) was not identified on Pt-segregated Pt3Ni(111), indicating that alloying Pt with Ni influences the intermediates of ORR, and leads to only the dissociation mechanism of chemisorption state OOH species being involved in acid medium on Pt-segregated Pt3Ni(111). By contrast, the dissociation mechanisms of chemisorbed O2 molecule with top-bridge-top configuration and OOH species both were involved on pure Pt(111). The rds of the entire four-electron ORR was changed after Pt alloying with Ni. The rds of the entire ORR is the proton and electron transfer to O2 to form OOH on Pt-segregated Pt3Ni(111), whereas it is the reaction of O atom protonation to form OH species on pure Pt(111), indicating that sublayer Ni strongly influences the rds of ORR. The comparison of the ORR mechanisms explained that Pt3Ni alloy enhanced the ORR electrocatalytic activity more than pure Pt. The effect of electrode potential on ORR pathway on the pure Pt and Pt3Ni alloy was considered to obtain further insights into the electrochemical reduction of O2. Results showed that the proton and electron transfer becomes difficult at high potential. The ORR can easily proceed when the electrode potential lowers. For pure Pt- and Pt-based alloys, this phenomenon may imply the origin of the overpotential.

  17. The Effects of Argument Quality and Involvement Type on Attitude Formation and Attitude Change: A Test of Dual-Process and Social Judgment Predictions

    Science.gov (United States)

    Park, Hee Sun; Levine, Timothy R.; Kingsley Westerman, Catherine Y.; Orfgen, Tierney; Foregger, Sarah

    2007-01-01

    Involvement has long been theoretically specified as a crucial factor determining the persuasive impact of messages. In social judgment theory, ego-involvement makes people more resistant to persuasion, whereas in dual-process models, high-involvement people are susceptible to persuasion when argument quality is high. It is argued that these…

  18. Highly active mesoporous ferrihydrite supported pt catalyst for formaldehyde removal at room temperature.

    Science.gov (United States)

    Yan, Zhaoxiong; Xu, Zhihua; Yu, Jiaguo; Jaroniec, Mietek

    2015-06-01

    Ferrihydrite (Fh) supported Pt (Pt/Fh) catalyst was first prepared by combining microemulsion and NaBH4 reduction methods and investigated for room-temperature removal of formaldehyde (HCHO). It was found that the order of addition of Pt precursor and ferrihydrite in the preparation process has an important effect on the microstructure and performance of the catalyst. Pt/Fh was shown to be an efficient catalyst for complete oxidation of HCHO at room temperature, featuring higher activity than magnetite supported Pt (Pt/Fe3O4). Pt/Fh and Pt/Fe3O4 exhibited much higher catalytic activity than Pt supported over calcined Fh and TiO2. The abundance of surface hydroxyls, high Pt dispersion and excellent adsorption performance of Fh are responsible for superior catalytic activity and stability of the Pt/Fh catalyst. This work provides some indications into the design and fabrication of the cost-effective and environmentally benign catalysts with excellent adsorption and catalytic oxidation performances for HCHO removal at room temperature.

  19. Microbial synthesis of bimetallic PdPt nanoparticles for catalytic reduction of 4-nitrophenol.

    Science.gov (United States)

    Tuo, Ya; Liu, Guangfei; Dong, Bin; Yu, Huali; Zhou, Jiti; Wang, Jing; Jin, Ruofei

    2017-02-01

    Bimetallic nanoparticles are generally believed to have improved catalytic activity and stability due to geometric and electronic changes. In this work, biogenic-Pd (bio-Pd), biogenic-Pt (bio-Pt), and biogenic-PdPt (bio-PdPt) nanoparticles were synthesized by Shewanella oneidensis MR-1 in the absence or presence of quinone. Compared with direct microbial reduction process, the addition of anthraquinone-2,6-disulfonate (AQDS) could promote the reduction efficiency of Pd(II) or/and Pt(IV) and result in decrease of particles size. All kinds of nanoparticles could catalyze 4-nitrophenol reduction by NaBH4 and their catalytic activities took the following order: bio-PdPt (AQDS) ∼ bio-PdPt > bio-Pd (AQDS) > bio-Pd > bio-Pt (AQDS) ∼ bio-Pt. Moreover, the bio-PdPt (AQDS) nanoparticles could be reused for 6 cycles. We believe that this simple and efficient biosynthesis approach for synthesizing bimetallic bio-PdPt nanocatalysts is important for preparing active and stable catalysts.

  20. The Orosomucoid 1 protein is involved in the vitamin D – mediated macrophage de-activation process

    Energy Technology Data Exchange (ETDEWEB)

    Gemelli, Claudia, E-mail: claudia.gemelli@unimore.it [Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena (Italy); Center for Regenerative Medicine, University of Modena and Reggio Emilia, Via Gottardi 100, 41125 Modena (Italy); Martello, Andrea; Montanari, Monica; Zanocco Marani, Tommaso; Salsi, Valentina; Zappavigna, Vincenzo; Parenti, Sandra; Vignudelli, Tatiana; Selmi, Tommaso; Ferrari, Sergio; Grande, Alexis [Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena (Italy)

    2013-12-10

    Orosomucoid 1 (ORM1), also named Alpha 1 acid glycoprotein A (AGP-A), is an abundant plasma protein characterized by anti-inflammatory and immune-modulating properties. The present study was designed to identify a possible correlation between ORM1 and Vitamin D3 (1,25(OH)2D3), a hormone exerting a widespread effect on cell proliferation, differentiation and regulation of the immune system. In particular, the data described here indicated that ORM1 is a 1,25(OH)2D3 primary response gene, characterized by the presence of a VDRE element inside the 1 kb sequence of its proximal promoter region. This finding was demonstrated with gene expression studies, Chromatin Immunoprecipitation and luciferase transactivation experiments and confirmed by VDR full length and dominant negative over-expression. In addition, several experiments carried out in human normal monocytes demonstrated that the 1,25(OH)2D3 – VDR – ORM1 pathway plays a functional role inside the macrophage de-activation process and that ORM1 may be considered as a signaling molecule involved in the maintenance of tissue homeostasis and remodeling. - Highlights: • ORM1 is a Vitamin D primary response gene. • VD and its receptor VDR are involved in the de-activation process mediated by human resident macrophages. • The signaling pathway VD-VDR-ORM1 plays an important role in the control of macrophage de-activation process. • ORM1 may be defined as a signaling molecule implicated in the maintenance of tissue homeostasis and remodeling.

  1. Inflammatory and fibrotic processes are involved in the cardiotoxic effect of sunitinib: Protective role of L-carnitine.

    Science.gov (United States)

    Blanca, Antonio J; Ruiz-Armenta, María V; Zambrano, Sonia; Miguel-Carrasco, José L; Arias, José L; Arévalo, Miguel; Mate, Alfonso; Aramburu, Oscar; Vázquez, Carmen M

    2016-01-22

    Sunitinib (Su) is currently approved for treatment of several malignances. However, along with the benefits of disease stabilization, cardiovascular toxicities have also been increasingly recognized. The aim of this study was to analyze which mechanisms are involved in the cardiotoxicity caused by Su, as well as to explore the potential cardioprotective effects of l-carnitine (LC). To this end, four groups of Wistar rats were used: (1) control; (2) rats treated with 400mg LC/kg/day; (3) rats treated with 25mg Su/kg/day; and (4) rats treated with LC+Su simultaneously. In addition, cultured rat cardiomyocytes were treated with an inhibitor of nuclear factor kappa B (NF-κB), in order to examine the role of this transcription factor in this process. An elevation in the myocardial expression of pro-inflammatory cytokines, together with an increase in the mRNA expression of NF-κB, was observed in Su-treated rats. These results were accompanied by an increase in the expression of pro-fibrotic factors, nitrotyrosine and NOX 2 subunit of NADPH oxidase; and by a decrease in that of collagen degradation factor. Higher blood pressure and heart rate levels were also found in Su-treated rats. All these alterations were inhibited by co-administration of LC. Furthermore, cardiotoxic effects of Su were blocked by NF-κB inhibition. Our results suggest that: (i) inflammatory and fibrotic processes are involved in the cardiac toxicity observed following treatment with Su; (ii) these processes might be mediated by the transcription factor NF-κB; (iii) LC exerts a protective effect against arterial hypertension, cardiac inflammation and fibrosis, which are all observed after Su treatment.

  2. Preparation of L11-CoPt/MgO/L11-CoPt tri-layer film on Ru(0001 underlayer

    Directory of Open Access Journals (Sweden)

    Mitsuru Ohtake

    2016-05-01

    Full Text Available A CoPt/MgO/CoPt tri-layer film is prepared on an Ru(0001 single-crystal underlayer at 300 °C by ultra-high vacuum magnetron sputtering. The growth behavior and the crystallographic properties are investigated by reflection high-energy electron diffraction, x-ray diffraction, and cross-sectional transmission electron microscopy. A fully epitaxial CoPt/MgO/CoPt film is formed on the Ru underlayer. The lower CoPt, the MgO, and the upper CoPt layers consist of two (111 variants whose atomic stacking sequences of close-packed plane along the perpendicular direction are ABCABC... and ACBACB... The lower and the upper CoPt layers involve metastable L11 structure, whereas the crystal structure of MgO layer is B1. Flat and atomically sharp interfaces are formed between the layers. The tri-layer film shows a strong perpendicular magnetic anisotropy reflecting the magnetocrystalline anisotropy of L11 crystal. The present study shows that an epitaxial L11-CoPt/MgO/L11-CoPt tri-layer film with perpendicular magnetic anisotropy can be formed by using a low substrate temperature of 300 °C.

  3. Efficient C-C bond splitting on Pt monolayer and sub-monolayer catalysts during ethanol electro-oxidation: Pt layer strain and morphology effects.

    Science.gov (United States)

    Loukrakpam, Rameshwori; Yuan, Qiuyi; Petkov, Valeri; Gan, Lin; Rudi, Stefan; Yang, Ruizhi; Huang, Yunhui; Brankovic, Stanko R; Strasser, Peter

    2014-09-21

    Efficient catalytic C-C bond splitting coupled with complete 12-electron oxidation of the ethanol molecule to CO2 is reported on nanoscale electrocatalysts comprised of a Pt monolayer (ML) and sub-monolayer (sML) deposited on Au nanoparticles (Au@Pt ML/sML). The Au@Pt electrocatalysts were synthesized using surface limited redox replacement (SLRR) of an underpotentially deposited (UPD) Cu monolayer in an electrochemical cell reactor. Au@Pt ML showed improved catalytic activity for ethanol oxidation reaction (EOR) and, unlike their Pt bulk and Pt sML counterparts, was able to generate CO2 at very low electrode potentials owing to efficient C-C bond splitting. To explain this, we explore the hypothesis that competing strain effects due to the Pt layer coverage/morphology (compressive) and the Pt-Au lattice mismatch (tensile) control surface chemisorption and overall activity. Control experiments on well-defined model Pt monolayer systems are carried out involving a wide array of methods such as high-energy X-ray diffraction, pair-distribution function (PDF) analysis, in situ electrochemical FTIR spectroscopy, and in situ scanning tunneling microscopy. The vibrational fingerprints of adsorbed CO provide compelling evidence on the relation between surface bond strength, layer strain and morphology, and catalytic activity.

  4. Resistive switching of Pt/TiO x /Pt devices fabricated on flexible Parylene-C substrates

    Science.gov (United States)

    Khiat, Ali; Cortese, Simone; Serb, Alexander; Prodromakis, Themistoklis

    2017-01-01

    Pt/TiO x /Pt resistive switching (RS) devices are considered to be amongst the most promising candidates in memristor family and the technology transfer to flexible substrates could open the way to new opportunities for flexible memory implementations. Hence, an important goal is to achieve a fully flexible RS memory technology. Nonetheless, several fabrication challenges are present and must be solved prior to achieving reliable device fabrication and good electronic performances. Here, we propose a fabrication method for the successful transfer of Pt/TiO x /Pt stack onto flexible Parylene-C substrates. The devices were electrically characterised, exhibiting both digital and analogue memory characteristics, which are obtained by proper adjustment of pulsing schemes during tests. This approach could open new application possibilities of these devices in neuromorphic computing, data processing, implantable sensors and bio-compatible neural interfaces.

  5. Degradation of the remanent ferromagnetic state under the action of ferroelectric relaxation processes in Co/(1-x)PMN-xPT/Co hybrids: Possible implications on cryogenic and room-temperature applications

    Science.gov (United States)

    Stamopoulos, D.; Zeibekis, M.; Vertsioti, G.; Zhang, S. J.

    2014-08-01

    Low-dimensional hybrid structures of heterogeneous constituents usually exhibit abnormal properties, a fact that makes such hybrids attractive for various cryogenic and room-temperature applications. Here, we studied Co/(1 - x)Pb(Mg1/3Nb2/3)O3-xPbTiO3/Co (Co/PMN-xPT/Co) with x = 0.29 and 0.30, specifically focusing on the evolution of the remanent ferromagnetic state, mrem of the Co outer layers in the whole temperature range from 300 K down to 10 K, upon application of an external electric field, Eex. We observed that mrem was vulnerable to degradation through the occurrence of electric field-induced magnetic instabilities (EMIs) that appeared only when Eex ≠ 0 kV/cm and were facilitated as Eex increases. However, EMIs completely ceased below a characteristic temperature Tces = 170 K even for the maximum |Eex| = 5 kV/cm applied in this work. A direct comparison of the magnetization data of the Co/PMN-xPT/Co hybrids reported here with the electromechanical properties of the parent PMN-xPT crystals plausibly indicates that EMIs are motivated by the coupling of the ferromagnetic domains of the Co outer layers with the ferroelectric domains of the PMN-xPT crystal. These results highlight the drawback of EMIs in relevant hybrids and delimit the temperature regime for the reliable operation of the Co/PMN-xPT/Co ones studied here.

  6. The Deceptively Simple N170 Reflects Network Information Processing Mechanisms Involving Visual Feature Coding and Transfer Across Hemispheres

    Science.gov (United States)

    Ince, Robin A. A.; Jaworska, Katarzyna; Gross, Joachim; Panzeri, Stefano; van Rijsbergen, Nicola J.; Rousselet, Guillaume A.; Schyns, Philippe G.

    2016-01-01

    A key to understanding visual cognition is to determine “where”, “when”, and “how” brain responses reflect the processing of the specific visual features that modulate categorization behavior—the “what”. The N170 is the earliest Event-Related Potential (ERP) that preferentially responds to faces. Here, we demonstrate that a paradigmatic shift is necessary to interpret the N170 as the product of an information processing network that dynamically codes and transfers face features across hemispheres, rather than as a local stimulus-driven event. Reverse-correlation methods coupled with information-theoretic analyses revealed that visibility of the eyes influences face detection behavior. The N170 initially reflects coding of the behaviorally relevant eye contralateral to the sensor, followed by a causal communication of the other eye from the other hemisphere. These findings demonstrate that the deceptively simple N170 ERP hides a complex network information processing mechanism involving initial coding and subsequent cross-hemispheric transfer of visual features. PMID:27550865

  7. Bacterial communities and syntrophic associations involved in anaerobic oxidation of methane process of the Sonora Margin cold seeps, Guaymas Basin.

    Science.gov (United States)

    Vigneron, Adrien; Cruaud, Perrine; Pignet, Patricia; Caprais, Jean-Claude; Gayet, Nicolas; Cambon-Bonavita, Marie-Anne; Godfroy, Anne; Toffin, Laurent

    2014-09-01

    The Sonora Margin cold seeps present on the seafloor a patchiness pattern of white microbial mats surrounded by polychaete and gastropod beds. These surface assemblages are fuelled by abundant organic inputs sedimenting from the water column and upward-flowing seep fluids. Elevated microbial density was observed in the underlying sediments. A previous study on the same samples identified anaerobic oxidation of methane (AOM) as the potential dominant archaeal process in these Sonora Margin sediments, probably catalysed by three clades of archaeal anaerobic methanotrophs (ANME-1, ANME-2 and ANME-3) associated with bacterial syntrophs. In this study, molecular surveys and microscopic observations investigating the diversity of Bacteria involved in AOM process, as well as the environmental parameters affecting the composition and the morphologies of AOM consortia in the Sonora Margin sediments were carried out. Two groups of Bacteria were identified within the AOM consortia, the Desulfosarcina/Desulfococcus SEEP SRB-1a group and a Desulfobulbus-related group. These bacteria showed different niche distributions, association specificities and consortia architectures, depending on sediment surface communities, geochemical parameters and ANME-associated phylogeny. Therefore, the syntrophic AOM process appears to depend on sulphate-reducing bacteria with different ecological niches and/or metabolisms, in a biofilm-like organic matrix. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  8. Dry (CO2) reforming of methane over Pt catalysts studied by DFT and kinetic modeling

    Science.gov (United States)

    Niu, Juntian; Du, Xuesen; Ran, Jingyu; Wang, Ruirui

    2016-07-01

    Dry reforming of methane (DRM) is a well-studied reaction that is of both scientific and industrial importance. In order to design catalysts that minimize the deactivation and improve the selectivity and activity for a high H2/CO yield, it is necessary to understand the elementary reaction steps involved in activation and conversion of CO2 and CH4. In our present work, a microkinetic model based on density functional theory (DFT) calculations is applied to explore the reaction mechanism for methane dry reforming on Pt catalysts. The adsorption energies of the reactants, intermediates and products, and the activation barriers for the elementary reactions involved in the DRM process are calculated over the Pt(1 1 1) surface. In the process of CH4 direct dissociation, the kinetic results show that CH dissociative adsorption on Pt(1 1 1) surface is the rate-determining step. CH appears to be the most abundant species on the Pt(1 1 1) surface, suggesting that carbon deposition is not easy to form in CH4 dehydrogenation on Pt(1 1 1) surface. In the process of CO2 activation, three possible reaction pathways are considered to contribute to the CO2 decomposition: (I) CO2* + * → CO* + O*; (II) CO2* + H* → COOH* + * → CO* + OH*; (III) CO2* + H* → mono-HCOO* + * → bi-HCOO* + * [CO2* + H* → bi-HCOO* + *] → CHO* + O*. Path I requires process to overcome the activation barrier of 1.809 eV and the forward reaction is calculated to be strongly endothermic by 1.430 eV. In addition, the kinetic results also indicate this process is not easy to proceed on Pt(1 1 1) surface. While the CO2 activation by H adsorbed over the catalyst surface to form COOH intermediate (Path II) is much easier to be carried out with the lower activation barrier of 0.746 eV. The Csbnd O bond scission is the rate-determining step along this pathway and the process needs to overcome the activation barrier of 1.522 eV. Path III reveals the CO2 activation through H adsorbed over the catalyst

  9. Dampak Implementasi Erp dalam Perbaikan Sistem Distribusi pada PT. Semen Gresik

    Directory of Open Access Journals (Sweden)

    I Gusti Made Karmawan

    2013-12-01

    Full Text Available This study describes how to implement an ERP system at PT Semen Gresik and compares the positive and negative effects of the implementation in the distribution process improvement. The benefits that can be obtained from this paper is obtaining information of how to implement an ERP system and the positive and negative effects of ERP implementation at PT Semen Gresik in the distribution process improvement. This study was done through documentation review to obtain the description of distribution process in the inventory material planning at PT Semen Gresik. The study resulted in a comparison between the positive and negative aspects as an effect from ERP implementation process at PT Semen Gresik in distribution process improvement. The ERP implementation process at PT Semen Gresik does not only provide more efficiency and effectiveness of distribution system, but also consequences of the impact from the effectiveness and efficiency obtained.

  10. tDCS application over the STG improves the ability to recognize and appreciate elements involved in humor processing.

    Science.gov (United States)

    Manfredi, Mirella; Proverbio, Alice Mado; Gonçalves Donate, Ana Paula; Macarini Gonçalves Vieira, Sofia; Comfort, William Edgar; De Araújo Andreoli, Mariana; Boggio, Paulo Sérgio

    2017-03-15

    The superior temporal gyrus (STG) has been found to play a crucial role in the recognition of actions and facial expressions and may, therefore, be critical for the processing of humorous information. Here we investigated whether tDCS application to the STG would modulate the ability to recognize and appreciate the comic element in serious and comedic situations of misfortune. To this aim, the effects of different types of tDCS stimulation on the STG were analyzed during a task in which the participants were instructed to categorize various misfortunate situations as "comic" or "not comic". Participants underwent three different tDCS conditions: Anodal-right/Cathodal-left; Cathodal-right/Anodal-left; Sham. Images depicting people involved in accidents were grouped into three categories based on the facial expression of the victim: angry or painful (Affective); bewildered and funny (Comic); and images that did not contain the victim's face (No Face). An improvement in mean reaction times in response to both the Comic and No Face stimuli was observed following Anodal-left/Cathodal-right stimulation when compared to sham stimulation. This suggests that this stimulation type reduced the reaction times to socio-emotional complex scenes, regardless of facial expression. The Anodal-right/Cathodal-left stimulation reduced the mean reaction times for Comic stimuli only, suggesting that specifically the right STG may be involved in facial expression recognition and in the appreciation of the comic element in misfortunate situations. These results suggest a functional hemispheric asymmetry in STG response to social stimuli: the left STG might have a role in a general comprehension of social complex situations, while the right STG may be involved in the ability to recognize and integrate specific emotional aspects in a complex scene.

  11. Pt···Pt vs Pt···S contacts between Pt-containing heterobimetallic lantern complexes.

    Science.gov (United States)

    Baddour, Frederick G; Fiedler, Stephanie R; Shores, Matthew P; Bacon, Jeffrey W; Golen, James A; Rheingold, Arnold L; Doerrer, Linda H

    2013-12-01

    A trio of Pt-based heterobimetallic lantern complexes of the form [(py)PtM(SAc)4(py)] (M = Co, 1; Ni, 2; Zn, 3) with unusual octahedral coordination of Pt(II) was prepared from a reaction of [PtM(SAc)4] with excess pyridine. These dipyridine lantern complexes could be converted to monopyridine derivatives with gentle heat to give the series [PtM(SAc)4(py)] (M = Co, 4; Ni, 5; Zn, 6). An additional family of the form [PtM(SAc)4(pyNH2)] (M = Co, 7; Ni, 8; Zn, 9) was synthesized from reaction of [PtM(SAc)4(OH2)] or [PtM(SAc)4] with 4-aminopyridine. Dimethylsulfoxide and N,N-dimethylformamide were also determined to react with [PtM(SAc)4] (M = Co, Ni), respectively, to give [PtCo(SAc)4(DMSO)](DMSO), 10, and [PtNi(SAc)4(DMF)](DMF), 11. Structural and magnetic data for these compounds and those for two other previously published families, [PtM(tba)4(OH2)] and [PtM(SAc)4(L)], L = OH2, pyNO2, are used to divide the structures among three distinct categories based on Pt···Pt and Pt···S distances. In general, the weaker donors H2O and pyNO2 seem to favor metallophilicity and antiferromagnetic coupling between 3d metal centers. When Pt···S interactions are favored over Pt···Pt ones, no coupling is observed and the pKa of the pyridine donor correlates with the interlantern S···S distance. UV-vis-NIR electronic and (1)H NMR spectra provide complementary characterization as well.

  12. Identifying a network of brain regions involved in aversion-related processing: a cross-species translational investigation

    Directory of Open Access Journals (Sweden)

    Dave J Hayes

    2011-10-01

    Full Text Available The ability to detect and respond appropriately to aversive stimuli is essential for all organisms, from fruit flies to humans. This suggests the existence of a core neural network which mediates aversion-related processing. Human imaging studies on aversion have highlighted the involvement of various cortical regions, such as the prefrontal cortex, while animal studies have focused largely on subcortical regions like the periaqueductal gray and hypothalamus. However, whether and how these regions form a core neural network of aversion remains unclear. To help determine this, a translational cross-species investigation in humans (i.e. meta-analysis and other animals (i.e. systematic review of functional neuroanatomy was performed. Our results highlighted the recruitment of the anterior cingulate cortex, the anterior insula, and the amygdala as well as other subcortical (e.g. thalalmus, midbrain and cortical (e.g. orbitofrontal regions in both animals and humans. Importantly, involvement of these regions remained independent of sensory modality. This study provides evidence for a core neural network mediating aversion in both animals and humans. This not only contributes to our understanding of the trans-species neural correlates of aversion but may also carry important implications for psychiatric disorders where abnormal aversive behaviour can often be observed.

  13. Premature temporal theta (PT theta).

    Science.gov (United States)

    Hughes, J R; Fino, J J; Hart, L A

    1987-07-01

    A distinctive pattern called premature temporal theta (PT theta) was studied in 436 infants, ranging in age from 24 to 46 weeks. The pattern is seen in early prematurity, maximizes at 29-31 weeks and then diminishes and disappears near term. Usually the pattern is found independently on both temporal areas, but with a right-sided preference. Patients without PT theta or with a significantly low amount had either neurological or non-neurological (medical) conditions. With age there is a tendency for an increase in frequency and a decrease in amplitude. Five different peaks in the amount of this pattern are seen at approximately every month. Unilateral PT theta tends to be seen in older babies, more often on the right side and with an abnormal EEG. An abnormal EEG is usually associated with a delay in both the appearance and disappearance of this wave form. PT theta is also associated mainly with REM or active sleep. A polynomial rather than an exponential or power function best describes these data with changes of age. PT theta may arise from the inferior temporal gyrus and/or especially the transverse gyrus.

  14. Specific involvement of atypical PKCζ/PKMζ in spinal persistent nociceptive processing following peripheral inflammation in rat

    Directory of Open Access Journals (Sweden)

    Marchand Fabien

    2011-11-01

    Full Text Available Abstract Background Central sensitization requires the activation of various intracellular signalling pathways within spinal dorsal horn neurons, leading to a lowering of activation threshold and enhanced responsiveness of these cells. Such plasticity contributes to the manifestation of chronic pain states and displays a number of features of long-term potentiation (LTP, a ubiquitous neuronal mechanism of increased synaptic strength. Here we describe the role of a novel pathway involving atypical PKCζ/PKMζ in persistent spinal nociceptive processing, previously implicated in the maintenance of late-phase LTP. Results Using both behavioral tests and in vivo electrophysiology in rats, we show that inhibition of this pathway, via spinal delivery of a myristoylated protein kinase C-ζ pseudo-substrate inhibitor, reduces both pain-related behaviors and the activity of deep dorsal horn wide dynamic range neurons (WDRs following formalin administration. In addition, Complete Freund's Adjuvant (CFA-induced mechanical and thermal hypersensitivity was also reduced by inhibition of PKCζ/PKMζ activity. Importantly, this inhibition did not affect acute pain or locomotor behavior in normal rats and interestingly, did not inhibited mechanical allodynia and hyperalgesia in neuropathic rats. Pain-related behaviors in both inflammatory models coincided with increased phosphorylation of PKCζ/PKMζ in dorsal horn neurons, specifically PKMζ phosphorylation in formalin rats. Finally, inhibition of PKCζ/PKMζ activity decreased the expression of Fos in response to formalin and CFA in both superficial and deep laminae of the dorsal horn. Conclusions These results suggest that PKCζ, especially PKMζ isoform, is a significant factor involved in spinal persistent nociceptive processing, specifically, the manifestation of chronic pain states following peripheral inflammation.

  15. Trypanosoma brucei PUF9 regulates mRNAs for proteins involved in replicative processes over the cell cycle.

    Directory of Open Access Journals (Sweden)

    Stuart K Archer

    2009-08-01

    Full Text Available Many genes that are required at specific points in the cell cycle exhibit cell cycle-dependent expression. In the early-diverging model eukaryote and important human pathogen Trypanosoma brucei, regulation of gene expression in the cell cycle and other processes is almost entirely post-transcriptional. Here, we show that the T. brucei RNA-binding protein PUF9 stabilizes certain transcripts during S-phase. Target transcripts of PUF9--LIGKA, PNT1 and PNT2--were identified by affinity purification with TAP-tagged PUF9. RNAi against PUF9 caused an accumulation of cells in G2/M phase and unexpectedly destabilized the PUF9 target mRNAs, despite the fact that most known Puf-domain proteins promote degradation of their target mRNAs. The levels of the PUF9-regulated transcripts were cell cycle dependent, peaking in mid- to late- S-phase, and this effect was abolished when PUF9 was targeted by RNAi. The sequence UUGUACC was over-represented in the 3' UTRs of PUF9 targets; a point mutation in this motif abolished PUF9-dependent stabilization of a reporter transcript carrying the PNT1 3' UTR. LIGKA is involved in replication of the kinetoplast, and here we show that PNT1 is also kinetoplast-associated and its over-expression causes kinetoplast-related defects, while PNT2 is localized to the nucleus in G1 phase and redistributes to the mitotic spindle during mitosis. PUF9 targets may constitute a post-transcriptional regulon, encoding proteins involved in temporally coordinated replicative processes in early G2 phase.

  16. Effect of Pt coverage in Pt-deposited Pd nanostructure electrodes on electrochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ah-Reum; Lee, Young-Woo; Kwak, Da-Hee; Park, Kyung-Won [Soongsil University, Seoul (Korea, Republic of)

    2015-06-15

    We have fabricated Pt-deposited Pd electrodes via a two-gun sputtering deposition system by separately operating Pd and Pt target as a function of sputtering time of Pt target. For Pt-deposited Pd electrodes (Pd/Pt-X), Pd were first deposited on the substrates at 20 W for 5min, followed by depositing Pt on the Pd-only electrodes as a function of sputtering time (X=1, 3, 5, 7, and 10min) at 20W on the Pt target. As the sputtering time of Pt target increased, the portion of Pt on the Pd electrodes increased, representing an increased coverage of Pt on the Pd electrodes. The Pd/Pt-7 electrode having an optimized Pt coverage exhibits an excellent electrocatalytic activity for methanol oxidation reaction.

  17. Catalytic and DRIFTS study of the WGS reaction on Pt-based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Vignatti, Ch.; Avila, M.S.; Apesteguia, C.R.; Garetto, T.F. [Catalysis Science and Engineering Research Group (GICIC), Instituto de Investigaciones en Catalisis y Petroquimica - INCAPE - (UNL-CONICET), Santiago del Estero 2654, 3000 Santa Fe (Argentina)

    2010-07-15

    The water-gas shift (WGS) activity of Pt/SiO{sub 2}, Pt/CeO{sub 2} and Pt/TiO{sub 2} catalysts was studied by in-situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). Samples contained a similar amount of Pt, between 0.34 and 0.50%, and were characterized by employing a variety of physical and spectroscopic techniques. The catalyst activities were evaluated through both CO conversion versus temperature and CO conversion versus time tests. The DRIFTS spectra were obtained on stream during the WGS reaction at increasing temperatures, from 303 to 573 K. Reduced ceria was the only active support and promoted the WGS reaction on surface bridging OH groups that react with CO to form formate intermediates. Pt/SiO{sub 2} was more active than CeO{sub 2} and catalyzed the WGS reaction through a monofunctional redox mechanism on metallic Pt sites. The CO conversion turnover rate was more than one order of magnitude greater on Pt/CeO{sub 2} than on Pt/SiO{sub 2} showing that the reaction proceeds faster via a bifunctional metal-support mechanism. Platinum on Pt/CeO{sub 2} increased the concentration of OH groups by increasing the ceria reduction extent and also provided a faster pathway for the formation of formate intermediates in comparison to CeO{sub 2} support. Pt/TiO{sub 2} catalysts were clearly more active than Pt/CeO{sub 2}. The WGS reaction on Pt/TiO{sub 2} was catalyzed via a bifunctional metal-support mechanism, probably involving the activation of CO and water on the metal and the support, respectively. The role of platinum on Pt/TiO{sub 2} was critical for promoting the reduction of Ti{sup 4+} ions to Ti{sup 3+} which creates oxygen vacancies in the support to efficiently activate water. (author)

  18. Electron transport in a Pt-CO-Pt nanocontact: Density functional theory calculations

    DEFF Research Database (Denmark)

    Strange, Mikkel; Thygesen, Kristian Sommer; Jacobsen, Karsten Wedel

    2006-01-01

    We have performed first-principles calculations for the mechanic and electric properties of pure Pt nanocontacts and a Pt contact with a single CO molecule adsorbed. For the pure Pt contacts we see a clear difference between point contacts and short chains in good agreement with experiments. We i...... of the transmission function for the Pt-CO-Pt contact, and show that the conductance is largely determined by the local d band at the Pt apex atoms....

  19. TiN@nitrogen-doped carbon supported Pt nanoparticles as high-performance anode catalyst for methanol electrooxidation

    Science.gov (United States)

    Zhang, Jun; Ma, Li; Gan, Mengyu; Fu, Shenna; Zhao, Yi

    2016-08-01

    In this paper, TiN@nitrogen-doped carbons (NDC) composed of a core-shell structure are successfully prepared through self-assembly and pyrolysis treatment using γ-aminopropyltriethoxysilane as coupling agent, polyaniline as carbon and nitrogen source, respectively. Subsequently, TiN@NDC supporting Pt nanoparticles (Pt/TiN@NDC) are obtained by a microwave-assisted polyol process. The nitrogen-containing functional groups and TiN nanoparticles play a critical role in decreasing the average particle size of Pt and improving the electrocatalytic activity of Pt/TiN@NDC. Transmission electron microscope results reveal that Pt nanoparticles are uniformly dispersed in the TiN@NDC surface with a narrow particle size ranging from 1 to 3 nm in diameter. Moreover, the Pt/TiN@NDC catalyst shows significantly improved catalytic activity and high durability for methanol electrooxidation in comparison with Pt/NDC and commercial Pt/C catalysts, revealed by cyclic voltammetry and chronoamperometry. Strikingly, this novel Pt/TiN@NDC catalyst reveals a better CO tolerance related to Pt/NDC and commercial Pt/C catalysts, which due to the bifunctional mechanism and strong metal-support interaction between Pt and TiN@NDC. In addition, the probable reaction steps for the electrooxidation of CO adspecies on Pt NPs on the basis of the bifunctional mechanism are also proposed. These results indicate that the TiN@NDC is a promising catalyst support for methanol electrooxidation.

  20. Metarhizium anisopliae host-pathogen interaction: differential immunoproteomics reveals proteins involved in the infection process of arthropods.

    Science.gov (United States)

    Santi, Lucélia; Silva, Walter O B; Pinto, Antônio F M; Schrank, Augusto; Vainstein, Marilene H

    2010-04-01

    Metarhizium anisopliae is an entomopathogenic fungus well characterized for the biocontrol of a wide range of plagues. Its pathogenicity depends on the secretion of hydrolytic enzymes that degrade the host cuticle. To identify proteins involved in the infection process and in host specify, immunoproteomic analysis was performed using antiserum produced against crude extract of M. anisopliae cultured in the presence of Rhipicephalus (Boophilus) microplus and Dysdercus peruvianus cuticles. Spots detected using antisera produced against M. anisopliae cultured in cuticles and spore surface proteins, but not with antiserum against M. anisopliae cultured in glucose, were identified so as to give insights about the infection process. An MS/MS allowed the identification of proteases, like elastase, trypsin, chymotrypsin, carboxypeptidase and subtilisin (Pr1A, Pr1I and PR1J), chitinases, DNase I and proline-rich protein. Chymotrypsin and Pr1I were inferred as host specific, being recognized in D. peruvianus infection only. This research represents an important contribution to the understanding the adaptation mechanisms of M. anisopliae to different hosts.

  1. Effect of counterpart metals in carbon-supported Pt-based catalysts prepared using radiation chemical method

    Science.gov (United States)

    Okazaki, Tomohisa; Seino, Satoshi; Matsuura, Yoshiyuki; Otake, Hiroaki; Kugai, Junichiro; Ohkubo, Yuji; Nitani, Hiroaki; Nakagawa, Takashi; Yamamoto, Takao A.

    2017-04-01

    The process of nanoparticle formation by radiation chemical synthesis in a heterogeneous system has been investigated. Carbon-supported Pt-based bimetallic nanoparticles were synthesized using a high-energy electron beam. Rh, Cu, Ru, and Sn were used as counterpart metals. The nanoparticles were characterized by inductively coupled plasma atomic emission spectrometry, transmission electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. PtRh formed a uniform random alloy nanoparticle, while Cu partially formed an alloy with Pt and the remaining Cu existed as CuO. PtRu formed an alloy structure with a composition distribution of a Pt-rich core and Ru-rich shell. No alloying was observed in PtSn, which had a Pt-SnO2 structure. The alloy and oxide formation mechanisms are discussed considering the redox potentials, the standard enthalpy of oxide formation, and the solid solubilities of Pt and the counterpart metals.

  2. Selective laser extraction of the Pt group metals

    Energy Technology Data Exchange (ETDEWEB)

    Fadeeva, S.; Krynetsky, B.; Prokhorov, A.; Zhidkov, A. [General Physics Institute, Russian Academy of Science, Moscow (Russian Federation)

    1995-11-15

    The interest to the platinum-group metals extraction from solutions, especially industry waste, is stimulated by their extraordinary chemical inert. The traditional chemical methods of the extraction are uneffective. Have been investigated process of the extraction of metal Pt-group from acid solutions. Discussed processes reduction of noble metals by resonance laser action.

  3. Pd-Pt loaded graphene aerogel on nickel foam composite as binder-free anode for a direct glucose fuel cell unit

    Science.gov (United States)

    Tsang, Chi Him A.; Leung, D. Y. C.

    2017-09-01

    Fabrication of electrocatalyst for direct glucose fuel cell (DGFC) operation involves destructive preparation methods with the use of stabilizer like binder, which may cause activity depreciation. Binder-free electrocatalytic electrode becomes a possible solution to the above problem. Binder-free bimetallic Pd-Pt loaded graphene aerogel on nickel foam plates with different Pd/Pt ratios (1:2.32, 1:1.62, and 1:0.98) are successfully fabricated through a green one-step mild reduction process producing a Pd-Pt/GO/nickel form plate (NFP) composite. Anode with the binder-free electrocatalysts exhibit a strong activity in a batch type DGFC unit under room temperature. The effects of glucose and KOH concentrations, and the Pd/Pt ratios of the electrocatalyst on the DGFC performance are also studied. Maximum power density output of 1.25 mW cm-2 is recorded with 0.5 M glucose/3 M KOH as the anodic fuel, and Pd1Pt0.98/GA/NFP as catalyst, which is the highest obtained so far among other types of electrocatalyst.

  4. New methods of controlled monolayer-to-multilayer deposition of Pt for designing electrocatalysts at an atomic level

    Directory of Open Access Journals (Sweden)

    J. X. WANG

    2001-12-01

    Full Text Available Two new methods for monolayer-to-multileyer Pt deposition are presented. One involves Pt deposition by the replacement of an UPD metal monolayer on an electrode surface and the other the spontaneous deposition of Pt on Ru. The first method, exemplified by the replacement of a Cu monolayer on a Au(111 surface, occurs as a spontaneous irreversible redox reaction in which the Cu monolayer is oxidized by Pt cations, which are reduced and simultaneously deposited. The second method is illustrated by the deposition of Pt on a Ru(0001 surface and on carbon-supported Ru nanoparticles. This deposition takes place upon immersion of a UHV-prepared Ru(0001 crystal or Ru nanoparticles, reduced in H2, in a solution containing PtCl62- ions. The oxidation of Ru to RuOH by a local cell mechanism appears to be coupled with Pt deposition. This method facilitates the design of active Pt-Ru catalysts with ultimately low Pt loadings. Only a quarter of a monolayer of Pt on Ru nanoparticles yields an electrocatalyst with higher activity and CO tolerance for H2/CO oxidation than commercial Pt-Ru alloy electrocatalysts with considerably higher Pt loadings.

  5. Genes involved in the osteoarthritis process identified through genome wide expression analysis in articular cartilage; the RAAK study.

    Directory of Open Access Journals (Sweden)

    Yolande F M Ramos

    Full Text Available Identify gene expression profiles associated with OA processes in articular cartilage and determine pathways changing during the disease process.Genome wide gene expression was determined in paired samples of OA affected and preserved cartilage of the same joint using microarray analysis for 33 patients of the RAAK study. Results were replicated in independent samples by RT-qPCR and immunohistochemistry. Profiles were analyzed with the online analysis tools DAVID and STRING to identify enrichment for specific pathways and protein-protein interactions.Among the 1717 genes that were significantly differently expressed between OA affected and preserved cartilage we found significant enrichment for genes involved in skeletal development (e.g. TNFRSF11B and FRZB. Also several inflammatory genes such as CD55, PTGES and TNFAIP6, previously identified in within-joint analyses as well as in analyses comparing preserved cartilage from OA affected joints versus healthy cartilage were among the top genes. Of note was the high up-regulation of NGF in OA cartilage. RT-qPCR confirmed differential expression for 18 out of 19 genes with expression changes of 2-fold or higher, and immunohistochemistry of selected genes showed a concordant change in protein expression. Most of these changes associated with OA severity (Mankin score but were independent of joint-site or sex.We provide further insights into the ongoing OA pathophysiological processes in cartilage, in particular into differences in macroscopically intact cartilage compared to OA affected cartilage, which seem relatively consistent and independent of sex or joint. We advocate that development of treatment could benefit by focusing on these similarities in gene expression changes and/or pathways.

  6. Stress-induced resistance to the fear memory labilization/reconsolidation process. Involvement of the basolateral amygdala complex.

    Science.gov (United States)

    Espejo, Pablo Javier; Ortiz, Vanesa; Martijena, Irene Delia; Molina, Victor Alejandro

    2016-10-01

    Consolidated memories can enter into a labile state after reactivation followed by a restabilization process defined as reconsolidation. This process can be interfered with Midazolam (MDZ), a positive allosteric modulator of the GABA-A receptor. The present study has evaluated the influence of prior stress on MDZ's interfering effect. We also assessed the influence of both systemic and intra-basolateral amygdala (BLA) infusion of d-cycloserine (DCS), a partial agonist of the NMDA receptors, on the MDZ effect in previously stressed rats. Furthermore, we analyzed the effect of stress on the expression of Zif-268 and the GluN2B sites, two molecular markers of the labilization/reconsolidation process, following reactivation. The results revealed that prior stress resulted into a memory trace that was insensitive to the MDZ impairing effect. Both systemic and intra-BLA DCS administration previous to reactivation restored MDZ's disruptive effect on memory reconsolidation in stressed animals. Further, reactivation enhanced Zif-268 expression in the BLA in control unstressed rats, whereas no elevation was observed in stressed animals. In agreement with the behavioral findings, DCS restored the increased level of Zif-268 expression in the BLA in stressed animals. Moreover, memory reactivation in unstressed animals elevated GluN2B expression in the BLA, thus suggesting that this effect is involved in memory destabilization, whereas stressed animals did not reveal any changes. These findings are consistent with resistance to the MDZ effect in these rats, indicating that stress exposure prevents the onset of destabilization following reactivation. In summary, prior stress limited both the occurrence of the reactivation-induced destabilization and restabilization. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Photodeposition of Pt on Colloidal CdS and CdSe/CdS Semiconductor Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Dukovic, Gordana; Merkle, Maxwell G.; Nelson, James H.; Hughes, Steven M.; Alivisatos, A. Paul

    2008-08-06

    Semiconductor photocatalysis has been identified as a promising avenue for the conversion of solar energy into environmentally friendly fuels, most notably by the production of hydrogen from water.[1-5] Nanometer-scale materials in particular have attracted considerable scientific attention as the building blocks for light-harvesting applications.[6,7] Their desirable attributes include tunability of the optical properties with size, amenability to relatively inexpensive low-temperature processing, and a high degree of synthetic sophistication leading to increasingly complex and multi-functional architectures. For photocatalysis in particular, the high surface-to-volume ratios in nanoscale materials should lead to an increased availability of carriers for redox reactions on the nanoparticle surface. Recombination of photoexcited carriers directly competes with photocatalytic activity.[3] Charge separation is often achieved with multi-component heterostructures. An early example is the case of TiO2 powders functionalized with Pt and RuO2 particles, where photoexcited electrons are transferred to Pt (the reduction site) and holes to RuO2 (the oxidation site).[8] More recently, many colloidally synthesized nanometer-scale metal-semiconductor heterostructures have been reported.[7,9,10] A majority of these structures are made by thermal methods.[7,10] We have chosen to study photochemical formation of metal-semiconductor heterostructures. The detailed understanding of the mechanisms involved in photodeposition of metals on nanometer-scale semiconductors is necessary to enable a high degree of synthetic control. At the same time, because the results of metal deposition can be directly observed by electron microscopy, it can be used to understand how factors such as nanocrystal composition, shape, carrier dynamics, and surface chemistry influence the photochemical properties of semiconductor nanocrystals. In this communication, we report on the photodeposition of Pt on

  8. Preparation and characterization of Pt supported on graphene with enhanced electrocatalytic activity in fuel cell

    Science.gov (United States)

    Xin, Yuchen; Liu, Jian-guo; Zhou, Yong; Liu, Wenming; Gao, Jian; Xie, Yun; Yin, Ying; Zou, Zhigang

    Pt nanoparticles are deposited onto graphene sheets via synchronous reduction of H 2PtCl 6 and graphene oxide (GO) suspension using NaBH 4. Lyophilization is introduced to avoid irreversible aggregation of graphene (G) sheets, which happens during conventional drying process. Pt/G catalysts reveal a high catalytic activity for both methanol oxidation and oxygen reduction reaction compared to Pt supported on carbon black (Pt/C). The performance of Pt/G catalysts is further improved after heat treatment in N 2 atmosphere at 300 °C for 2 h, and the peak current density of methanol oxidation for Pt/G after heat treatment is almost 3.5 times higher than Pt/C. Transmission electron microscope (TEM) images show that the Pt particles are uniformly distributed on graphene sheets. X-ray photoelectron spectroscopy (XPS) results demonstrate that the interaction between Pt and graphene is enhanced during annealing. It suggests that graphene has provided a new way to improve electrocatalytic activity of catalyst for fuel cell.

  9. Tuning the magnetic properties of Fe50-xMnxPt50 thin films

    Science.gov (United States)

    Manoharan, Ezhil A.; Mankey, Gary; Hong, Yang-Ki

    2017-09-01

    The magnetic and structural properties of highly ordered (S ∼ 0.82) epitaxial Fe50-xMnxPt50 thin films were investigated. L10 Fe50-xMnxPt50 (x = 0, 6, 9, 12 and 15) thin films with a constant thickness of 45 nm were prepared by co-sputtering Fe50Pt50 and Mn50Pt50 on to MgO (100) single crystal substrate. We find a significant increase in the coercivity for FeMnPt thin films. We have shown that this increase coincides with a tetragonal distortion, while a recent first principles study of Mn doped FePt showed the sub lattice ordering of ferromagnetically aligned Mn atoms would lead to increase in magnetic anisotropy in the FeMnPt ternary alloy system with fixed Pt concentration. At x = 12 the coercivity has increased by 46.4% relative to that of Fe50Pt50 (x = 0). We attribute the increase in coercivity to the tetragonal distortion as the experimentally determined c/a ratio is larger than the expected c/a ratio for ferromagnetically ordered Mn atoms in the sublattice at the concentration x = 12. High temperature deposition and high temperature annealing was applied to achieve large coercivity in Mn doped FePt as these process lead to the observed tetragonal distortion.

  10. Thermally Stable Nanocatalyst for High Temperature Reactions: Pt-Mesoporous Silica Core-Shell Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Sang Hoon; Park, J.Y.; Tsung, C.-K.; Yamada, Y.; Yang, P.; Somorjai, G.A.

    2008-10-25

    Recent advances in colloidal synthesis enabled the precise control of size, shape and composition of catalytic metal nanoparticles, allowing their use as model catalysts for systematic investigations of the atomic-scale properties affecting catalytic activity and selectivity. The organic capping agents stabilizing colloidal nanoparticles, however, often limit their application in high-temperature catalytic reactions. Here we report the design of a high-temperature stable model catalytic system that consists of Pt metal core coated with a mesoporous silica shell (Pt{at}mSiO{sub 2}). While inorganic silica shells encaged the Pt cores up to 750 C in air, the mesopores directly accessible to Pt cores made the Pt{at}mSiO{sub 2} nanoparticles as catalytically active as bare Pt metal for ethylene hydrogenation and CO oxidation. The high thermal stability of Pt{at}mSiO{sub 2} nanoparticles permitted high-temperature CO oxidation studies, including ignition behavior, which was not possible for bare Pt nanoparticles because of their deformation or aggregation. The results suggest that the Pt{at}mSiO{sub 2} nanoparticles are excellent nanocatalytic systems for high-temperature catalytic reactions or surface chemical processes, and the design concept employed in the Pt{at}mSiO{sub 2} core-shell catalyst can be extended to other metal-metal oxide compositions.

  11. Analysis of nodulation kinetics in Frankia-Discaria trinervis symbiosis reveals different factors involved in the nodulation process.

    Science.gov (United States)

    Gabbarini, Luciano Andrés; Wall, Luis Gabriel

    2008-08-01

    The induction of root nodule development in actinorhizal symbiosis would depend on the concentration of factors produced by the bacteria and the plant. A detailed analysis of nodulation description parameters revealed different factors related to the nodulation process. The initial time for nodulation (t(0)), the initial nodulation rate (v(0)) and the total time of nodule development (t(NOD)) were defined and consequently quantified in different experimental conditions: co-inoculation of Discaria trinervis with increasing concentrations of different non-infective bacteria together with the full compatible infective Frankia strain (the indicator strain) used at a limiting concentration or by changing plant factor(s) concentration. All the above nodulation parameters were modified by changing doses of full compatibility infective strain Frankia BCU110501; v(0) appears to be an expression of symbiotic recognition between partners as only fully symbiotic indicator Frankia BCU110501 was able to change it; t(0) seems not to reflect symbiotic recognition because it can also be modified by non-infective Frankia but suggest the existence of a basic level of plant microbe recognition. The initial time for nodulation t(0), reflecting the time required for the early interactions toward nodulation, is an inverse measure of the ability to establish early interactions toward nodulation. The increase in plant factors concentration also reduces t(0) values, suggesting that a plant factor is involved and favors very early interactions. Increases in plant factors concentration also modify the final number of nodules per plant and the nodule cluster profile along the taproot as an expression of the autoregulation phenomenon. Meanwhile, Frankia inoculums' concentration, either infective or not, modified t(NOD) in an opposite way plant factors did. In conclusion, the analysis of nodulation kinetics appears to be an appropriate tool to investigate factors involved in the symbiotic

  12. Ab-initio study of the coadsorption of Li and H on Pt(001), Pt(110) and Pt(111) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Saad, Farida [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria); Zemirli, Mourad, E-mail: zemirlimourad@mail.ummto.dz [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria); Benakki, Mouloud; Bouarab, Said [Laboratoire de Physique et Chimie Quantique, Faculte des Sciences, Universite Mouloud Mammeri, 15000 Tizi-Ouzou (Algeria)

    2012-02-15

    The coadsorption of Li and H atoms on Pt(001), Pt(110) and Pt(111) surfaces is studied using density functional theory with generalised gradient approximation. In all calculations Li, H and the two topmost layers of the metal were allowed to relax. At coverage of 0.25 mono-layer in a p(2 Multiplication-Sign 2) unit cell, lithium adsorption at the hollow site for the three surfaces is favoured over top and bridge sites. The most favoured adsorption sites for H atom on the Pt(001) and Pt(110) surfaces are the top and bridge sites, while on Pt(111) surface the fcc site appears to be slightly favoured over the hcp site. The coadsorption of Li and atomic hydrogen shows that the interaction between the two adsorbates is stabilising when they are far from each other. The analysis of Li, H and Pt local density of states shows that Li strongly interacts with the Pt surfaces.

  13. Study of pressing effects and variation in Pt charge in the anode on the performance of membrane electrode assemblies; Estudio de los efectos de prensado y variacion de la carga de Pt en el anodo en el rendimiento de ensambles membrana-electrodo

    Energy Technology Data Exchange (ETDEWEB)

    Albarran S, Irma Lorena; Flores Hernandez, J. Roberto; Cano Castillo, Ulises [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico). E-mail: ilas@iie.org.mx; Loyola, Felix (UNAM, Facultad de Quimica, Mexico D.F. (Mexico)

    2009-09-15

    Fabricating membrane electrode assemblies (MEA) involves different variables that determine their performance, such as: amount of the catalyst, concentration of the different solvents used in the fabrication of the catalyst dye, use of a thermomechanical process to increase the degree of adhesion between the catalyst layers and the membrane, etc. This work studied the effect of the Pt charge in the anode on performance, as well as the effect of the thermomechanical process on the fabrication of MEAs. It is evident that the optimal Pt charge should be that which provides good performance during an acceptable useful lifetime at a competitive cost. This work presents the results obtained by varying the Pt charge in the anode between 1.0 and 0.4 mgPt/cm{sup ²} while maintaining a constant charge of 1 mgPt/cm{sup ²} in the cathode. It also shows the comparison between the polarization curves and the active areas obtained in the MEAs with and without pressing during their fabrication. [Spanish] En la fabricacion de los Ensambles Membrana-Electrodo (MEA's) intervienen diferentes variables que determinan su desempeno, como lo son: cantidad de catalizador, concentracion de los diferentes solventes que se emplean en la fabricacion de la tinta catalitica, el uso de un proceso termomecanico para incrementar el grado de adherencia entre las capas cataliticas y la membrana, etc. De las variables anteriormente mencionadas, en este trabajo se estudio el efecto de la carga anodica de Pt en el desempeno, asi como del proceso termomecanico en la fabricacion de MEA's. Es evidente que la carga optima de Pt debe ser aquella que proporcione un buen rendimiento por un periodo de vida util aceptable a un costo competitivo. En este trabajo se presentan los resultados obtenidos al variar la carga de Pt en el anodo entre 1.0 a 0.4 mgPt/cm{sup ²} manteniendo una carga constante de 1 mgPt/cm{sup ²} en el catodo. Tambien se muestra la comparacion de las curvas de polarizacion y las

  14. New certification process starts. Pt. 2. Application of Building Information Modeling (BIM) for the certification according to DGNB; Zertifizierungsprozess auf ''neuen Beinen''. T. 2. Anwendung von Building Informationen (BIM) zur Zertifizierung nach DGNB

    Energy Technology Data Exchange (ETDEWEB)

    Essig, Bernd [SCHOLZE Consulting GmbH, Leinfelden-Echterdingen (Germany). Geschaeftsbereich Ingenieur-Beratungsleistungen in Facility-, Informations-, Qualitaets-, Nachhaltigkeitsmanagement und Energieberatung; Ernst, Tatjana [SCHOLZE Consulting GmbH, Leinfelden-Echterdingen (Germany)

    2013-04-01

    The overall life cycle plays a significant role in the certification by German Sustainable Building Council (Stuttgart, Federal Republic of Germany). In order that certification becomes much more than only a documentation, comprehensive data are requested already in an early phase of planning. Early investigations of alternatives may have a significant influence on the life cycle of a building. But, from where do the auditors achieve these amounts of data without overcharging the partners involved in the planning process with questions. The Building Information Modelling contributes to the development of the future enhancement of process quality by an innovative information management.

  15. Formalized process description in practise. Pt. 1. Design of a process description according to guideline VDI/VDE 3682; Formalisierte Prozessbeschreibung in der praktischen Anwendung. T. 1. Erstellen einer Prozessbeschreibung nach VDI/VDE-Richtlinie 3682

    Energy Technology Data Exchange (ETDEWEB)

    Felleisen, Michael [Hochschule Pforzheim (Germany). Inst. fuer Angewandte Forschung IAF; Ulrich, Alexander [Robert Bosch GmbH, Schwieberdingen (Germany); Fay, Alexander [Helmut-Schmidt-Univ./Univ. der Bundeswehr Hamburg (Germany). Inst. fuer Automatisierungstechnik; Enste, Udo [LeiKon GmbH, Herzogenrath (Germany); Polke, Burkard [Rheinische Fachhochschule Koeln (Germany)

    2009-07-01

    With the publication of the guideline VDI/VDE 3682 in September 2005 [1], a description method for formalized process descriptions was available. Based on this guideline a development project was initiated, funded by the Federal Ministry of Education and Research (BMBF) in order to develop and evaluate a graphical engineering tool for improved description of processes. The approach should be realized using formalized process descriptions according to the guideline VDI/VDE 3682. This paper introduces the possibilities of a formalized process description and explains functions of the recently developed software tool at the example of waste treatment. The second part will describe the validation and the benefit of a formalized process description. (orig.)

  16. Efficient C–C bond splitting on Pt monolayer and sub-monolayer catalysts during ethanol electro-oxidation: Pt layer strain and morphology effects

    Energy Technology Data Exchange (ETDEWEB)

    Loukrakpam, Rameshwori; Yuan, Qiuyi; Petkov, Valeri; Gan, Lin; Rudi, Stefan; Yang, Ruizhi; Huang, Yunhui; Brankovic, Stanko R.; Strasser, Peter (TU Berlin); (Soochow); (CMU); (Huazhong); (Houston)

    2014-07-23

    Efficient catalytic C–C bond splitting coupled with complete 12-electron oxidation of the ethanol molecule to CO2 is reported on nanoscale electrocatalysts comprised of a Pt monolayer (ML) and sub-monolayer (sML) deposited on Au nanoparticles (Au@Pt ML/sML). The Au@Pt electrocatalysts were synthesized using surface limited redox replacement (SLRR) of an underpotentially deposited (UPD) Cu monolayer in an electrochemical cell reactor. Au@Pt ML showed improved catalytic activity for ethanol oxidation reaction (EOR) and, unlike their Pt bulk and Pt sML counterparts, was able to generate CO2 at very low electrode potentials owing to efficient C–C bond splitting. To explain this, we explore the hypothesis that competing strain effects due to the Pt layer coverage/morphology (compressive) and the Pt–Au lattice mismatch (tensile) control surface chemisorption and overall activity. Control experiments on well-defined model Pt monolayer systems are carried out involving a wide array of methods such as high-energy X-ray diffraction, pair-distribution function (PDF) analysis, in situ electrochemical FTIR spectroscopy, and in situ scanning tunneling microscopy. The vibrational fingerprints of adsorbed CO provide compelling evidence on the relation between surface bond strength, layer strain and morphology, and catalytic activity.

  17. Insight into the Reaction Mechanisms of Methanol on PtRu/Pt(111): A Density Functional Study

    Science.gov (United States)

    Ding, Qiuyue; Xu, Wenbin; Sang, Pengpeng; Xu, Jing; Zhao, Lianming; He, Xiaoli; Guo, Wenyue

    2016-04-01

    Periodic DFT calculations have been performed to systematically investigate the mechanisms of methanol decomposition and oxidation on the PtRu/Pt(111) surface. Geometries and energies for the primary species involved are analyzed and the reaction network has been mapped out. The calculation shows that among three initial Csbnd H, Osbnd H, and Csbnd O bond scissions of methanol, the Osbnd H bond scission is found to be the most favorable and bears a lower energy barrier than the desorption of methanol. The decomposition of CH3O occurs via the path CH3O → CH2O → CHO → CO with the limiting step of the first dehydrogenation. Although the oxidation of CO is hindered by a high barrier, the CHO oxidation to CHOOH could occur facilely. Further decomposition of formic acid to CO2 and/or CO could occur via four possible pathways, that is, initial Csbnd H, Osbnd H, and Csbnd O bond activations as well as simultaneous activation of Csbnd H and Csbnd O bonds, where the first pathway, HCOOH → COOH → CO2, is the most favorable from a kinetic point of view. Compared to that on Pt(111), methanol on PtRu/Pt(111) prefers to decomposition rather than desorption and then oxidation via the favorable non-CO path with a lower rate-determining energy barrier of CH3O → CH2O for the whole reaction, which indicates that PtRu alloy can improved tolerance toward CO poisoning compared with pure Pt.

  18. PT-symmetric quantum theory

    Science.gov (United States)

    Bender, Carl M.

    2015-07-01

    The average quantum physicist on the street would say that a quantum-mechanical Hamiltonian must be Dirac Hermitian (invariant under combined matrix transposition and complex conjugation) in order to guarantee that the energy eigenvalues are real and that time evolution is unitary. However, the Hamiltonian H = p2 + ix3, which is obviously not Dirac Hermitian, has a positive real discrete spectrum and generates unitary time evolution, and thus it defines a fully consistent and physical quantum theory. Evidently, the axiom of Dirac Hermiticity is too restrictive. While H = p2 + ix3 is not Dirac Hermitian, it is PT symmetric; that is, invariant under combined parity P (space reflection) and time reversal T. The quantum mechanics defined by a PT-symmetric Hamiltonian is a complex generalization of ordinary quantum mechanics. When quantum mechanics is extended into the complex domain, new kinds of theories having strange and remarkable properties emerge. In the past few years, some of these properties have been verified in laboratory experiments. A particularly interesting PT-symmetric Hamiltonian is H = p2 - x4, which contains an upside-down potential. This potential is discussed in detail, and it is explained in intuitive as well as in rigorous terms why the energy levels of this potential are real, positive, and discrete. Applications of PT-symmetry in quantum field theory are also discussed.

  19. Cyclic-Oxidation Behavior of Multilayered Pt/Ru-Modified Aluminide Coating

    Institute of Scientific and Technical Information of China (English)

    Yingxue Song; Hideyuki Murakami; Chungen Zhou

    2011-01-01

    Multilayered Pt/Ru modified aluminide coating for thermal barrier coating (TBC) systems has been investigated. 2 μm Pt+2μm Ru+2 μm Pt was first deposited on nickel-base superalloy DZ125 by electrodeposition, and then the coating was treated by annealing and a conventional pack-cementation aluminizing process. The cyclic oxidation tests were carried out at 1423 K in air. It was found that the thermal cyclic oxidation resistance of Pt/Ru-modified aluminide coating was comparable to that of Pt-modified aluminide coating, which was much better than simply aluminized DZ125. The addition of Ru to Pt-modified aluminide coating increased the resistance to rumpling. The microstructures and phase constitutions of the coating before and after oxidation were investigated.

  20. Influence of surface preparation on atomic layer deposition of Pt films

    Institute of Scientific and Technical Information of China (English)

    Ge Liang; Hu Cheng; Zhu Zhiwei; Zhang Wei; Wu Dongping; Zhang Shili

    2012-01-01

    We report Pt deposition on a Si substrate by means of atomic layer deposition (ALD) using (methylcyclopentadienyl) trimethylplatinum (CH3CsH4Pt(CH3)3) and O2.Silicon substrates with both HF-last and oxidelast surface treatments are employed to investigate the influence of surface preparation on Pt-ALD.A significantlylonger incubation time and less homogeneity are observed for Pt growth on the HF-last substrate compared to the oxide-last substrate.An interfacial oxide layer at the Pt-Si interface is found inevitable even with HF treatment of the Si substrate immediately prior to ALD processing.A plausible explanation to the observed difference of Pt-ALD is discussed.

  1. Physics counterpart of the PT non-hermitian tight-binding chain

    CERN Document Server

    Jin, L

    2010-01-01

    We explore an alternative way of finding the link between a PT non-Hermitian Hamiltonian and a Hermitian one. Based on the analysis of the scattering problem for an imaginary potential and its time reversal process, it is shown that any real-energy eigenstate of a PT tight-binding lattice with on-site imaginary potentials shares the same wave function with a resonant transmission state of the corresponding Hermitian lattice embedded in a chain. It indicates that the PT eigenstate of a PT non-Hermitian Hamiltonian has connection to the resonance transmission state of the extended Hermitian Hamiltonian.

  2. Gram-Scale-Synthesized Pd2Co-Supported Pt Monolayer Electrocatalysts for Oxygen Reduction Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, W.; Sasaki, K; Su, D; Zhu, Y; Wang, J; Adzic, R

    2010-01-01

    Gram-scale synthesis of Pt{sub ML} electrocatalysts with a well-defined core-shell structure has been carried out using method involving galvanic displacement of an underpotential deposition Cu layer. The Pt shell thickness can be controlled by stepwise deposition. The Pt{at}Pd{sub 2}Co/C nanoparticles were characterized by X-ray powder diffraction, aberration-corrected scanning transmission electron microscopy, high-resolution energy-loss spectrometry, and in situ X-ray absorption spectroscopy. A complete Pt shell of 0.6 nm on a Pd{sub 2}Co core has been confirmed. The Pt{at}Pd{sub 2}Co/C core-shell electrocatalysts showed a very high activity for the oxygen reduction reaction; the Pt mass and specific activity were 0.72 A mg{sub Pt}{sup -1} and 0.5 mA cm{sup -2}, respectively (3.5 and 2.5 times higher than the corresponding values for commercial Pt catalysts), at 0.9 V in 0.1 M HClO{sub 4} at room temperature. In an accelerated potential cycling test, a loss in active surface area and a decrease in catalytic activity for gram-scale-synthesized Pt{sub ML} catalysts were also determined.

  3. Activator of G-protein signaling 8 is involved in VEGF-mediated signal processing during angiogenesis.

    Science.gov (United States)

    Hayashi, Hisaki; Al Mamun, Abdullah; Sakima, Miho; Sato, Motohiko

    2016-03-15

    Activator of G-protein signaling 8 (AGS8, also known as FNDC1) is a receptor-independent accessory protein for the Gβγ subunit, which was isolated from rat heart subjected to repetitive transient ischemia with the substantial development of collaterals. Here, we report the role of AGS8 in vessel formation by endothelial cells. Knockdown of AGS8 by small interfering RNA (siRNA) inhibited vascular endothelial growth factor (VEGF)-induced tube formation, as well as VEGF-stimulated cell growth and migration. VEGF stimulated the phosphorylation of the VEGF receptor-2 (VEGFR-2, also known as KDR), ERK1/2 and p38 MAPK; however, knockdown of AGS8 inhibited these signaling events. Signal alterations by AGS8 siRNA were associated with a decrease of cell surface VEGFR-2 and an increase of VEGFR-2 in the cytosol. Endocytosis blockers did not influence the decrease of VEGFR-2 by AGS8 siRNA, suggesting the involvement of AGS8 in VEGFR-2 trafficking to the plasma membrane. VEGFR-2 formed a complex with AGS8 in cells, and a peptide designed to disrupt AGS8-Gβγ interaction inhibited VEGF-induced tube formation. These data suggest a potential role for AGS8-Gβγ in VEGF signal processing. AGS8 might play a key role in tissue adaptation by regulating angiogenic events.

  4. The thumb subdomain of yeast mitochondrial RNA polymerase is involved in processivity, transcript fidelity and mitochondrial transcription factor binding.

    Science.gov (United States)

    Velazquez, Gilberto; Sousa, Rui; Brieba, Luis G

    2015-01-01

    Single subunit RNA polymerases have evolved 2 mechanisms to synthesize long transcripts without falling off a DNA template: binding of nascent RNA and interactions with an RNA:DNA hybrid. Mitochondrial RNA polymerases share a common ancestor with T-odd bacteriophage single subunit RNA polymerases. Herein we characterized the role of the thumb subdomain of the yeast mtRNA polymerase gene (RPO41) in complex stability, processivity, and fidelity. We found that deletion and point mutants of the thumb subdomain of yeast mtRNA polymerase increase the synthesis of abortive transcripts and the probability that the polymerase will disengage from the template during the formation of the late initial transcription and elongation complexes. Mutations in the thumb subdomain increase the amount of slippage products from a homopolymeric template and, unexpectedly, thumb subdomain deletions decrease the binding affinity for mitochondrial transcription factor (Mtf1). The latter suggests that the thumb subdomain is part of an extended binding surface area involved in binding Mtf1.

  5. Electrooxidation of ethanol on Pt and PtRu surfaces investigated by ATR surface-enhanced infrared absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcio F.; Camara, Giuseppe A., E-mail: giuseppe.silva@ufms.br [Departamento de Quimica, Universidade Federal do Mato Grosso do Sul, Campo Grande-MS (Brazil); Batista, Bruno C.; Boscheto, Emerson [Instituto de Quimica de Sao Carlos, Universidade de Sao Paulo, Sao Carlos-SP, (Brazil); Varela, Hamilton, E-mail: varela@iqsc.usp.br [Ertl Center for Electrochemistry and Catalysis, Gwangju Institute of Science and Technology (GIST), Gwangju (Korea, Republic of)

    2012-05-15

    Herein, it was investigated for the first time the electro-oxidation of ethanol on Pt and PtRu electrodeposits in acidic media by using in situ surface enhanced infrared absorption spectroscopy with attenuated total reflection (ATR-SEIRAS). The experimental setup circumvents the weak absorbance signals related to adsorbed species, usually observed for rough, electrodeposited surfaces, and allows a full description of the CO coverage with the potential for both catalysts. The dynamics of adsorption-oxidation of CO was accessed by ATR-SEIRAS experiments (involving four ethanol concentrations) and correlated with expressions derived from a simple kinetic model. Kinetic analysis suggests that the growing of the CO adsorbed layer is nor influenced by the presence of Ru neither by the concentration of ethanol. The results suggest that the C-C scission is not related to the presence of Ru and probably happens at Pt sites. (author)

  6. Resistive switching in Pt/TiO{sub 2}/Pt

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Doo Seok

    2008-08-15

    Recently, the resistive switching behavior in TiO{sub 2} has drawn attention due to its application to resistive random access memory (RRAM) devices. TiO{sub 2} shows characteristic non-volatile resistive switching behavior, i.e. reversible switching between a high resistance state (HRS) and a low resistance state (LRS). Both unipolar resistive switching (URS) and bipolar resistive switching (BRS) are found to be observed in TiO{sub 2} depending on the compliance current for the electroforming. In this thesis the characteristic current-voltage (I-V) hysteresis in three different states of TiO{sub 2}, pristine, URS-activated, and BRS-activated states, was investigated and understood in terms of the migration of oxygen vacancies in TiO{sub 2}. The I-V hysteresis of pristine TiO{sub 2} was found to show volatile behavior. That is, the temporary variation of the resistance took place depending on the applied voltage. However, the I-V hysteresis of URS- and BRS-activated states showed non-volatile resistive switching behavior. Some evidences proving the evolution of oxygen gas during electroforming were obtained from time-of-flight secondary ion mass spectroscopy analysis and the variation of the morphology of switching cells induced by the electroforming. On the assumption that a large number of oxygen vacancies are introduced by the electroforming process, the I-V behavior in electroformed switching cells was simulated with varying the distribution of oxygen vacancies in electroformed TiO{sub x} (x Pt/TiO{sub x} interface. The oxygen-related reactions given as a function of the applied voltage affect the distribution of oxygen vacancies in TiO{sub x}, consequently, the Schottky barrier height at the cathode/TiO{sub x} interface is influenced by the oxygen vacancy distribution. Therefore, the BRS behavior including the

  7. Differential electrochemical mass spectrometry study of Pt and PtSn nanocatalysts for direct ethanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Saidani, F.; Bommersbach, P.; Guay, D.; Mohamedi, M. [Quebec Univ., Institut National de la Recherche Scientifique, Varennes, PQ (Canada). Centre de l' Energie, Materiaux et Telecommunications; Rochefort, D. [Montreal Univ., PQ (Canada). Dept. of Chemistry

    2008-07-01

    This paper reported on a study that investigated Platinum (Pt) and Pt with tin (Sn) nanoparticles prepared under vacuum and under 2 Torr of He by pulsed laser ablation. This method was chosen because it is possible to control size of nanoparticles, structure and morphology of films by varying deposition conditions. The influence of deposition conditions on the electrocatalytic behaviour was determined. In particular, the objective of the study was to better understand the reaction mechanism involved during ethanol oxidation at Pt and PtSn catalysts by means of cyclic voltammetry combined with Differential Electrochemical Mass Spectrometry (DEMS), a powerful technique to elucidate the Ethanol Oxidation Reaction (EOR) mechanism. Ethanol was shown to be a very attractive liquid biofuel for direct-fuelled systems, since its partial oxidation products are less toxic than other alcohols. During pulsed laser ablation, the interaction between an intense laser and a target material resulted in the creation of plasma. This plasma enabled the transfer of matter from the target to the substrate. Highly nanocrystalline films can be prepared when deposition is performed into a moderate pressure gas. The electrochemical investigations showed that Pt deposited under 2 torr have a beneficial effect on the electrocatalytic activity towards ethanol oxidation. 5 refs., 1 fig.

  8. Controlling the Adsorption of Aromatic Compounds on Pt(111) with Oxygenate Substituents: From DFT to Simple Molecular Descriptors.

    Science.gov (United States)

    Réocreux, Romain; Huynh, Minh; Michel, Carine; Sautet, Philippe

    2016-06-01

    Aromatic chemistry on metallic surfaces is involved in many processes within the contexts of biomass valorization, pollutant degradation, or corrosion protection. Albeit theoretically and experimentally challenging, knowing the structure and the stability of aromatic compounds on such surfaces is essential to understand their properties. To gain insights on this topic, we performed periodic ab initio calculations on Pt(111) to determine a set of simple molecular descriptors that predict both the stability and the structure of aromatic adsorbates substituted with alkyl and alkoxy (or hydroxy) groups. While the van der Waals (vdW) interaction is controlled by the molecular weight and the deformation energy by both the nature and the relative position of the substituents to the surface, the chemical bonding can be correlated to the Hard and Soft Acids and Bases (HSAB) interaction energy. This work gives general insights on the interaction of aromatic compounds with the Pt(111) surface.

  9. Final report on numerical simulation of processes of hot sheet bending in the frame of the project EUREKA-FASP (EU353). v. 3. Pt. 5. Pt. 6. New source representation obtained by comparison with experimental temperature data; Parametric analyses of area heating processes in the sheet hot bending

    Energy Technology Data Exchange (ETDEWEB)

    Carmignani, B.; Toselli, G. [ENEA, Centro Ricerche `E. Clementel`, Bologna (Italy). Dip. Innovazione

    1996-10-01

    This work is the final report of the activity developed in the frame of the European project EUREKA-FASP (EU353) concerning the numerical simulation of the processes of the hot shaping or bending of large sheets, of interest of the ship-buildings, by the use of ABACUS code in its implicit version (ABAQUS/S). The work has been subdivided in 6 parts according to different considered aspects and made choices. Substantially, two different types of sheet heating processes have been considered, that is line heating and area heating processes, while two aims have been pursued; (1) to single out the best strategies in order to simulate the shaping of large sheets in a suitable way corresponding to the experience, adopting thermo-structural computation codes, as ABAQUS; (2) to verify and suggest, in some cases, orientations and indications for the design of an automate machine managed by an expert system (one of the aims of FASP project) for the heating of large sheets, able to provide the required shaping or bending of these sheets.

  10. Results of the Proficiency Test, PT1 and PT2, 2012

    DEFF Research Database (Denmark)

    Vendramin, Niccolò; Nicolajsen, Nicole; Christophersen, Maj-Britt

    A comparative test of diagnostic procedures was provided by the European Union Reference Laboratory (EURL) for Fish Diseases. The test was divided into proficiency test 1 (PT1) and proficiency test 2 (PT2). The number of National Reference Laboratories (NRLs) participating in PT1 and PT2 was 43...

  11. Oxygen reduction activity of Pt and Pt-alloys in acid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Paulus, Ursula A. [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Schmidt, Thomas J.; Stamenkovic, Vojislav R.; Markovic, Nenad M.; Ross, Philip N. [Material Science Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

    2001-07-01

    The oxygen reduction reaction (ORR) has been studied on polycrystalline (pc) Pt, Pt{sub 3}Ni and Pt{sub 3}Co bulk alloy electrodes and on carbon supported Pt, PtNi and PtCo alloy catalysts. Base voltammetry measurements as well as complementary Auger Electron Spectroscopy (AES) and Low Energy Ion Scattering (LEIS) on bulk electrodes and High Resolution Transmission Electron Microscopy (HRTEM)-analysis on the supported catalysts allow an estimation of the surface composition. By using the rotating ring-disk electrode (RRDE) technique both the kinetic analysis of the ORR and in parallel the detection and quantification of the amount of peroxide produced during the ORR are possible. The activity for the ORR increases in the order Pt < Pt{sub 3}Ni < Pt{sub 3}Co for equally prepared bulk alloys and Pt < Pt{sub 3}Ni {approx} Pt{sub 3}CO < PtCo for the carbon supported catalysts, respectively. It was proposed that the mechanism for the ORR is the same on pure Pt and the PtNi and PtCo alloys. (author)

  12. Synthesis and Electrocatalytic Performance of Multi-Component Nanoporous PtRuCuW Alloy for Direct Methanol Fuel Cells

    Directory of Open Access Journals (Sweden)

    Xiaoting Chen

    2015-06-01

    Full Text Available We have prepared a multi-component nanoporous PtRuCuW (np-PtRuCuW electrocatalyst via a combined chemical dealloying and mechanical alloying process. The X-ray diffraction (XRD, transmission electron microscopy (TEM and electrochemical measurements have been applied to characterize the microstructure and electrocatalytic activities of the np-PtRuCuW. The np-PtRuCuW catalyst has a unique three-dimensional bi-continuous ligament structure and the length scale is 2.0 ± 0.3 nm. The np-PtRuCuW catalyst shows a relatively high level of activity normalized to mass (467.1 mA mgPt−1 and electrochemically active surface area (1.8 mA cm−2 compared to the state-of-the-art commercial PtC and PtRu catalyst at anode. Although the CO stripping peak of np-PtRuCuW 0.47 V (vs. saturated calomel electrode, SCE is more positive than PtRu, there is a 200 mV negative shift compared to PtC (0.67 V vs. SCE. In addition, the half-wave potential and specific activity towards oxygen reduction of np-PtRuCuW are 0.877 V (vs. reversible hydrogen electrode, RHE and 0.26 mA cm−2, indicating a great enhancement towards oxygen reduction than the commercial PtC.

  13. Hydrogen Adsorption on Pt, Rh and Pt-Rh Electrodes

    Institute of Scientific and Technical Information of China (English)

    贾梦秋; A.M.Meretskyi

    2005-01-01

    The hydrogen adsorption on Pt-Rh alloys in sulfuric acid aqueous solutions was studied by the method of cathode pulses. Hydrogen adsorption on the electrode with all ratio of alloy components (ωRh = 0-100%) is well described by the Temkin logarithmic isotherm. The surface coverage by adsorbed hydrogen at the same potential is decreased with increasing content of rhodium in the system. A linear dependence of adsorption peak potential on the alloy compositions in the case of weakly bonded adsorbed hydrogen is established. Hydrogen adsorption heat as a function of surface coverage for Pt-Rh-electrodes was obtained. The shape of the current-potential curve and position of the weakly bonded hydrogen adsorption on the potential scale are all related to alloy compositions, thus can serve as the basis for the determination surface composition of allovs.

  14. Surface termination of CePt5/Pt (111 ): The key to chemical inertness

    Science.gov (United States)

    Praetorius, C.; Zinner, M.; Held, G.; Fauth, K.

    2015-11-01

    The surface termination of CePt5/Pt (111 ) is determined experimentally by LEED-IV. In accordance with recent theoretical predictions, a dense Pt terminated surface is being found. Whereas the CePt5 volume lattice comprises Pt kagome layers, additional Pt atoms occupy the associated hole positions at the surface. This finding provides a natural explanation for the remarkable inertness of the CePt5 intermetallic. Implications of the structural relaxations determined by LEED-IV analysis are discussed with regard to observations by scanning tunneling microscopy and electron spectroscopies.

  15. Highly active Pt3Pb and core-shell Pt3Pb-Pt electrocatalysts for formic acid oxidation.

    Science.gov (United States)

    Kang, Yijin; Qi, Liang; Li, Meng; Diaz, Rosa E; Su, Dong; Adzic, Radoslav R; Stach, Eric; Li, Ju; Murray, Christopher B

    2012-03-27

    Formic acid is a promising chemical fuel for fuel cell applications. However, due to the dominance of the indirect reaction pathway and strong poisoning effects, the development of direct formic acid fuel cells has been impeded by the low activity of existing electrocatalysts at desirable operating voltage. We report the first synthesis of Pt(3)Pb nanocrystals through solution phase synthesis and show they are highly efficient formic acid oxidation electrocatalysts. The activity can be further improved by manipulating the Pt(3)Pb-Pt core-shell structure. Combined experimental and theoretical studies suggest that the high activity from Pt(3)Pb and the Pt-Pb core-shell nanocrystals results from the elimination of CO poisoning and decreased barriers for the dehydrogenation steps. Therefore, the Pt(3)Pb and Pt-Pb core-shell nanocrystals can improve the performance of direct formic acid fuel cells at desired operating voltage to enable their practical application. © 2012 American Chemical Society

  16. Dry (CO{sub 2}) reforming of methane over Pt catalysts studied by DFT and kinetic modeling

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Juntian [Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education of PRC, Chongqing University, Chongqing, 400044 (China); College of Power Engineering, Chongqing University, Chongqing, 400044 (China); Du, Xuesen, E-mail: xuesendu@cqu.edu.cn [Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education of PRC, Chongqing University, Chongqing, 400044 (China); College of Power Engineering, Chongqing University, Chongqing, 400044 (China); Ran, Jingyu, E-mail: jyran@189.cn [Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education of PRC, Chongqing University, Chongqing, 400044 (China); College of Power Engineering, Chongqing University, Chongqing, 400044 (China); Wang, Ruirui [Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education of PRC, Chongqing University, Chongqing, 400044 (China); College of Power Engineering, Chongqing University, Chongqing, 400044 (China)

    2016-07-15

    Graphical abstract: - Highlights: • CH appears to be the most abundant species on Pt(1 1 1) surface in CH{sub 4} dissociation. • CO{sub 2}* + H* → COOH* + * → CO* + OH* is the dominant reaction pathway in CO{sub 2} activation. • Major reaction pathway in CH oxidation: CH* + OH* → CHOH* + * → CHO* + H* → CO* + 2H*. • C* + OH* → COH* + * → CO* + H* is the dominant reaction pathway in C oxidation. - Abstract: Dry reforming of methane (DRM) is a well-studied reaction that is of both scientific and industrial importance. In order to design catalysts that minimize the deactivation and improve the selectivity and activity for a high H{sub 2}/CO yield, it is necessary to understand the elementary reaction steps involved in activation and conversion of CO{sub 2} and CH{sub 4}. In our present work, a microkinetic model based on density functional theory (DFT) calculations is applied to explore the reaction mechanism for methane dry reforming on Pt catalysts. The adsorption energies of the reactants, intermediates and products, and the activation barriers for the elementary reactions involved in the DRM process are calculated over the Pt(1 1 1) surface. In the process of CH{sub 4} direct dissociation, the kinetic results show that CH dissociative adsorption on Pt(1 1 1) surface is the rate-determining step. CH appears to be the most abundant species on the Pt(1 1 1) surface, suggesting that carbon deposition is not easy to form in CH{sub 4} dehydrogenation on Pt(1 1 1) surface. In the process of CO{sub 2} activation, three possible reaction pathways are considered to contribute to the CO{sub 2} decomposition: (I) CO{sub 2}* + * → CO* + O*; (II) CO{sub 2}* + H* → COOH* + * → CO* + OH*; (III) CO{sub 2}* + H* → mono-HCOO* + * → bi-HCOO* + * [CO{sub 2}* + H* → bi-HCOO* + *] → CHO* + O*. Path I requires process to overcome the activation barrier of 1.809 eV and the forward reaction is calculated to be strongly endothermic by 1.430 eV. In

  17. Situation Concerning Public Information about and Involvement in the Decision-Making Processes in the Nuclear Sector. Public Opinion Review.

    Energy Technology Data Exchange (ETDEWEB)

    Prades, A.; Sala, R.; Lopez, M.

    2006-07-01

    This report summarizes the CIEMAT's contribution to the study {sup S}ituation concerning Public Information about and Involvement in the Decision-Making Processes in the Nuclear Sector{sup ,} contract number TREN/ 04/NUC/ S07.39556 between the European Commission and Mutadis Consultants. The research was composed by Mutadis Consultants and CEPN (Nuclear Protection Evaluation Centre) (France), University of Aberdeen (UK) and CIEMAT (Spain). The objective of the project was to build a detailed overview of the EU situation regarding information and participation practices in the nuclear domain, provide an elaborated assessment, and to produce reporting and recommendations in the field. CIEMAT contribution' focused on the review of public opinion polis. Thus, Eurobarometers Standard Surveys (EBs) were analysed to report about the European citizens' public opinion regarding public Information and participation in the nuclear field. Additionally, the International Social Survey Program (ISSP), and some additional national polis were analysed. In terms of the EU public opinion, the follow up of the public information and participation domains receiving as much attention as necessary. Extremely few questions dealing with the subject were identified in the Eurobarometers, the national polis and the ISSP (International Social Survey Program) surveys reviewed in this study. An unambiguous illustration of this lack of attention is the fact that no questions dealing with public participation issues emerged in the {sup n}uclear EBs{sup u}ntil 1998. Even though, Eurobarometers (EBs) still provide an invaluable source of information on the topics we are interested on at the EU allowing longitudinal descriptions (trend analysis) of some key issues in our area of interest. (Author) 11 refs.

  18. Novel blast furnace operation process involving charging with low-titanium vanadium-titanium magnetite carbon composite hot briquette

    Science.gov (United States)

    Zhao, Wei; Chu, Man-sheng; Wang, Hong-tao; Liu, Zheng-gen; Tang, Ya-ting

    2016-05-01

    An innovative process of blast furnace (BF) operation involving charging with low-titanium vanadium-titanium magnetite carbon composite hot briquette (LVTM-CCB) was proposed for utilizing LVTM and conserving energy. In this study, the effect of LVTM-CCB charging ratio on the softening, melting, and dripping behaviors of the mixed burden was explored systemically, and the migration of valuable elements V and Cr was extensively investigated. The results show that with increasing LVTM-CCB charging ratio, the softening interval T 40 - T 4 increases from 146.1°C to 266.1°C, and the melting interval T D - T S first decreases from 137.2°C to 129.5°C and then increases from 129.5°C to 133.2°C. Moreover, the cohesive zone becomes narrower and then wider, and its location shifts slightly downward. In addition, the recovery ratios of V and Cr in dripped iron first increase and then decrease, reaching maximum values of 14.552% and 28.163%, respectively, when the charging ratio is 25%. A proper LVTM-CCB charging ratio would improve the softening-melting behavior of the mixed burden; however, Ti(C,N) would be generated rapidly in slag when the charging ratio exceeds 25%, which is not favorable for BF operation. When considering the comprehensive softening-melting behavior of the mixed burden and the recovery ratios of V and Cr, the recommended LVTM-CCB charging ratio is 20%.

  19. Planetary wave coupling processes in the middle atmosphere (30 90 km): A study involving MetO and MFR data

    Science.gov (United States)

    Chshyolkova, T.; Manson, A. H.; Meek, C. E.; Avery, S. K.; Thorsen, D.; MacDougall, J. W.; Hocking, W.; Murayama, Y.; Igarashi, K.

    2006-02-01

    The MetO assimilated data and mesospheric winds provided by five medium frequency radars (MFR) from the Canada US Japan Opportunity (CUJO) network have been used to study coupling processes due to planetary waves (PWs) in the middle atmosphere. It is shown that there is strong vertical coupling between the stratosphere and mesosphere especially during winter months. However, not all observed disturbances in mesospheric winds can be explained by the simple propagation of PWs from below. In addition to the vertical coupling there is also weaker horizontal “inter-hemispheric” coupling during equinoxes. The data used are from December 2000 to December 2002. The time interval was chosen to include austral winters and springs of 2 years: the dynamically unusual year 2002, during which a major stratospheric warming involving a split vortex and wind reversals occurred in the Southern Hemisphere, and a more typical year 2001. The character of PW activity during these 2 years is compared. In contrast to the usually weak PW activity dominated by eastward motions, both strong eastward and westward propagating waves existed during austral winter of 2002. Wavelet spectra of MetO winds show strong peaks near 14 days that match similar signals observed in mesospheric winds at Antarctic stations [Dowdy et al., 2004. The large-scale dynamics of the mesosphere lower thermosphere during the SH stratospheric warming of 2002. Geophysical Research Letters 31, L14102. doi:10.1029/2004GL020282] during the stratospheric warming. It is suggested that this oscillation was generated at low atmospheric heights and propagated upward. The longer duration of the stratospheric mesospheric winter vortex (7 months) compared to that of the summer jet in the Northern Hemisphere provide equinoctial months when eastward winds dominate globally. Results suggest that during equinoxes, with favourable conditions, the PWs with ˜10-, 16- and 25-day periods can penetrate to the opposite hemisphere.

  20. Rho family GTP binding proteins are involved in the regulatory volume decrease process in NIH3T3 mouse fibroblasts.

    Science.gov (United States)

    Pedersen, Stine F; Beisner, Kristine H; Hougaard, Charlotte; Willumsen, Berthe M; Lambert, Ian H; Hoffmann, Else K

    2002-06-15

    The role of Rho GTPases in the regulatory volume decrease (RVD) process following osmotic cell swelling is controversial and has so far only been investigated for the swelling-activated Cl- efflux. We investigated the involvement of RhoA in the RVD process in NIH3T3 mouse fibroblasts, using wild-type cells and three clones expressing constitutively active RhoA (RhoAV14). RhoAV14 expression resulted in an up to fourfold increase in the rate of RVD, measured by large-angle light scattering. The increase in RVD rate correlated with RhoAV14 expression. RVD in wild-type cells was unaffected by the Rho kinase inhibitor Y-27632 and the phosphatidyl-inositol 3 kinase (PI3K) inhibitor wortmannin. The maximal rates of swelling-activated K+ (86 Rb+ as tracer) and taurine ([3H]taurine as tracer) efflux after a 30 % reduction in extracellular osmolarity were increased about twofold in cells with maximal RhoAV14 expression compared to wild-type cells, but were unaffected by Y-27632. The volume set points for activation of release of both osmolytes appeared to be reduced by RhoAV14 expression. The maximal taurine efflux rate constant was potentiated by the tyrosine phosphatase inhibitor Na(3)VO(4), and inhibited by the tyrosine kinase inhibitor genistein. The magnitude of the swelling-activated Cl- current (I(Cl,swell) ) was higher in RhoAV14 than in wild-type cells after a 7.5 % reduction in extracellular osmolarity, but, in contrast to 86Rb+ and [3H]taurine efflux, similar in both strains after a 30 % reduction in extracellular osmolarity. I(Cl,swell) was inhibited by Y-27632 and strongly potentiated by the myosin light chain kinase inhibitors ML-7 and AV25. It is suggested that RhoA, although not the volume sensor per se, is an important upstream modulator shared by multiple swelling-activated channels on which RhoA exerts its effects via divergent signalling pathways.

  1. Sentential context modulates the involvement of the motor cortex in action language processing: An fMRI study

    NARCIS (Netherlands)

    K.D.I. Schuil (Karen); M. Smits (Marion); R.A. Zwaan (Rolf)

    2013-01-01

    textabstractTheories of embodied cognition propose that language comprehension is based on perceptual and motor processes. More specifically, it is hypothesized that neurons processing verbs describing bodily actions, and those that process the corresponding physical actions, fire simultaneously

  2. Sentential context modulates the involvement of the motor cortex in action language processing: An fMRI study

    NARCIS (Netherlands)

    K.D.I. Schuil (Karen); M. Smits (Marion); R.A. Zwaan (Rolf)

    2013-01-01

    textabstractTheories of embodied cognition propose that language comprehension is based on perceptual and motor processes. More specifically, it is hypothesized that neurons processing verbs describing bodily actions, and those that process the corresponding physical actions, fire simultaneously dur

  3. PT Symmetry as a Generalization of Hermiticity

    CERN Document Server

    Wang, Qing-hai; Zhang, Jie-hong

    2010-01-01

    The Hilbert space in PT-symmetric quantum mechanics is formulated as a linear vector space with a dynamic weight function in the inner product. The most general PT-symmetric matrix Hamiltonians are constructed for 2*2 and 3*3 cases. In the former case, the PT-symmetric Hamiltonian represents the most general matrix Hamiltonian with a real spectrum. In both cases, the Hermitian matrix is shown to be a special case of PT-symmetric matrices. This finding confirms and strengthens the early belief that the PT-symmetric quantum mechanics is a generalization of the conventional Hermitian quantum mechanics.

  4. Metallization of cyanide-modified Pt(111) electrodes with copper

    DEFF Research Database (Denmark)

    Escribano, Maria Escudero; Wildi, Christopher; Mwanda, Jonathan A.

    2016-01-01

    The reduction of Cu2+ ions irreversibly attached to the surface of a cyanide-modified Pt(111) electrode via non-covalent or weakly covalent interactions with the N atom of adsorbed cyanide was studied using cyclic voltammetry (CV) and in situ scanning tunneling microscopy (STM). Both CV and STM...... provide evidence that the reduction of irreversibly adsorbed Cu2+ to Cu in Cu2+-free sulfuric acid solutions does not result in the stripping of the cyanide adlayer. This strongly suggests that the reduction process results in the metallization of the cyanide adlayer on Pt(111), yielding a platinum-cyanide...

  5. Achieving methodological alignment when combining QCA and PT in practice

    DEFF Research Database (Denmark)

    Beach, Derek

    2016-01-01

    negotiations, part of the broader phenomenon of the representation of voter views in public policies. The section develops a range of potential causes for congruence from the existing literature. Second, using a QCA-first design I undertake a fsQCA analysis of sufficiency. Utilized in a theory-building fashion......This article explores the practical challenges one faces when combining Qualitative Comparative Analysis (QCA) and Process-tracing (PT) in a manner that is consistent with their underlying assumptions about the nature of causal relationships. While PT builds on a mechanism-based understanding...

  6. Final report on numerical simulation of processes of hot sheet bending in the frame of the project EUREKA-FASP (EU353). V. 2. Pt. 4. Parametric studies on heating source for line heating processes

    Energy Technology Data Exchange (ETDEWEB)

    Carmignani, B.; Toselli, G. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dip. Innovazione

    1996-05-01

    This work is the final report of the activity developed in the frame of the European project EUREKA-FASP (EU353) concerning the numerical simulation of the processes of the hot shaping or bending of large sheets, of interest of the ship-buildings, by the use of ABACUS code in its implicit version (ABAQUS/S). The work has been subdivided in 6 Parts according to different considered aspects and made choices. Substantially, two different types of sheet heating processes have been considered, that is `Line Heating` and `Area Heating` processes, while two aims have been pursued; (1) to single out the best strategies in order to simulate the shaping of large sheets in a suitable way corresponding to the experience, adopting thermo-structural computation codes, as ABAQUS; (2) to verify and suggest, in some cases, orientations and indications for the design of an automate machine managed by an expert system (one of the aims of FASP project) for the heating of large sheets, able to provide the required shaping or bending of these sheets.

  7. Study of the Pt/Ru(0001) Interface

    DEFF Research Database (Denmark)

    Godowski, Jan P; Li, Zhe Shen; Bork, Jakob

    2007-01-01

    The growth process of platinum on Ru(0001) near room temperature was characterized using photoelectron spectroscopy of high resolution. The binding energy position and intensity of the Pt 4f7/2 and Ru 3d5/2 core levels as well as the shape and structure of the valence band spectra corresponding t...

  8. PMN-PT nanowires with a very high piezoelectric constant.

    Science.gov (United States)

    Xu, Shiyou; Poirier, Gerald; Yao, Nan

    2012-05-09

    A profound way to increase the output voltage (or power) of the piezoelectric nanogenerators is to utilize a material with higher piezoelectric constants. Here we report the synthesis of novel piezoelectric 0.72Pb(Mg(1/3)Nb(2/3))O(3)-0.28PbTiO(3) (PMN-PT) nanowires using a hydrothermal process. The unpoled single-crystal PMN-PT nanowires show a piezoelectric constant (d(33)) up to 381 pm/V, with an average value of 373 ± 5 pm/V. This is about 15 times higher than the maximum reported value of 1-D ZnO nanostructures and 3 times higher than the largest reported value of 1-D PZT nanostructures. These PMN-PT nanostructures are of good potential being used as the fundamental building block for higher power nanogenerators, high sensitivity nanosensors, and large strain nanoactuators.

  9. Electrical behaviour of PMN-PT-PVDF nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Shrabanee; Mishra, S K [MST Division, National Metallurgical Laboratory, Jamshedpur 834007 (India)], E-mail: shrabaneesen@yahoo.co.in

    2008-08-21

    Nanocomposites of polyvinyldene fluoride (PVDF) and a solid solution of lead magnesium niobate and lead titanate (0.65PMN-0.35PT) with varying composition ratios were prepared by the hot-press technique. The phase structure and morphology were studied by thermal analysis (DTA), x-ray diffraction and scanning electron microscopy. The PVDF sample showed an exothermic peak due to the crystallization of the PVDF phase, but with the addition of PMN-PT powders an extra peak appeared due to the crystallization of the pyrochlore phase present in the PMN-PT powder. The crystallite size of the prepared samples was found to be between 40 and 60 nm. The value of the relative permittivity increased with the increase in the ceramic concentration. The presence of a single semicircle confirmed the presence of the bulk effect only. The bulk conductivity indicated an Arrhenius type thermally activated process. The ac conductivity spectrum obeyed the Jonscher power law.

  10. PtSi Clustering in Silicon Probed by Transport Spectroscopy

    Directory of Open Access Journals (Sweden)

    Massimo Mongillo

    2013-12-01

    Full Text Available Metal silicides formed by means of thermal annealing processes are employed as contact materials in microelectronics. Control of the structure of silicide/silicon interfaces becomes a critical issue when the characteristic size of the device is reduced below a few tens of nanometers. Here, we report on silicide clustering occurring within the channel of PtSi/Si/PtSi Schottky-barrier transistors. This phenomenon is investigated through atomistic simulations and low-temperature resonant-tunneling spectroscopy. Our results provide evidence for the segregation of a PtSi cluster with a diameter of a few nanometers from the silicide contact. The cluster acts as a metallic quantum dot giving rise to distinct signatures of quantum transport through its discrete energy states.

  11. The formation mechanism of bimetallic PtRu alloy nanoparticles in solvothermal synthesis.

    Science.gov (United States)

    Mi, Jian-Li; Nørby, Peter; Bremholm, Martin; Becker, Jacob; Iversen, Bo B

    2015-10-21

    An understanding of the nucleation and growth mechanism of bimetallic nanoparticles in solvothermal synthesis is important for further development of nanoparticles with tailored nanostructures and properties. Here the formation of PtRu alloy nanoparticles in a solvothermal synthesis using metal acetylacetonate salts as precursors and ethanol as both the solvent and reducing agent has been studied by in situ synchrotron radiation powder X-ray diffraction (SR-PXRD). Unlike the classical mechanism for the synthesis of monodisperse sols, the nucleation and growth processes of bimetallic PtRu nanoparticles occur simultaneously under solvothermal conditions. In the literature co-reduction of Pt and Ru is often assumed to be required to form PtRu bimetallic nanocrystals, but it is shown that monometallic Pt nanocrystals nucleate first and rapidly grow to an average size of 5 nm. Subsequently, the PtRu bimetallic alloy is formed in the second nucleation stage through a surface nucleation mechanism related to the reduction of Ru. The calculated average crystallite size of the resulting PtRu nanocrystals is smaller than that of the primary Pt nanocrystals due to the large disorder in the PtRu alloyed structure.

  12. Te/Pt nanonetwork modified carbon fiber microelectrodes for methanol oxidation

    Science.gov (United States)

    Tsai, Hsiang-Yu; Shih, Zih-Yu; Lin, Zong-Hong; Chang, Huan-Tsung

    2013-05-01

    Te/Pt nanonetwork-decorated carbon fiber microelectrodes (CFMEs) have been fabricated and employed as anodic catalysts in a direct methanol fuel cell (DMFC). Te nanowires were prepared from tellurite ions (TeO32-) through a seed-mediated growth process and were deposited onto CFMEs to form three-dimensional Te nanonetworks. The Te nanonetworks then acted as a framework and reducing agent to reduce PtCl62- ions to form Te/Pt through a galvanic replacement reaction, leading to the formation of Te/PtCFMEs. By controlling the reaction time, the amount of Pt and morphology of Te/Pt nanonetworks were controlled, leading to various degrees of electrocatalytic activity. The Te/PtCFMEs provide a high electrochemical active surface area (129.2 m2 g-1), good catalytic activity (1.2 A mg-1), high current density (20.0 mA cm-2), long durability, and tolerance toward the poisoning species for methanol oxidation in 0.5 M sulfuric acid containing 1 M methanol. We have further demonstrated an enhanced current density by separately using 3 and 5 Te/PtCFMEs. Our results show that the low-cost, stable, and effective Te/PtCFMEs have great potential in the fabrication of cost-effective fuel cells.

  13. Four-wave mixing in a parity-time (PT)-symmetric coupler.

    Science.gov (United States)

    Wasak, T; Szańkowski, P; Konotop, V V; Trippenbach, M

    2015-11-15

    Parity-time (PT) symmetry allows for implementing controllable matching conditions for the four-wave mixing in 1D coupled waveguides. Different types of the process involving energy transition between slow and fast modes are established. In the case of defocusing Kerr media, the degenerated four-wave mixing is studied in detail. It is shown that unbroken PT symmetry supports the process existing in the conservative limit and, at the same time, originates new types of matching conditions, which cannot exist in the conservative system. In the former case, a slow beam splits into two fast beams, with nearly conserved total power, while in the latter case, one slow beam and one fast beam are generated. In the last process, the energy of the input primary slow beam is not changed and growth of the energy of the generated slow beam varies due to gain and loss of the medium. The appreciable generation of the fifth mode, i.e., the effect of the secondary resonant interactions, is observed.

  14. Perpendicular magnetic anisotropy of Co85Cr15/Pt multilayers

    Institute of Scientific and Technical Information of China (English)

    Pol Hwang; Baohe Li; Tao Yang; Zhonghai Zhai; Fengwu Zhu

    2004-01-01

    The CoCr/Pt bilayers and (CoCr/Pt)20 multilayers with Pt underlayer were prepared by DC magnetron sputtering. The effects of prepared condition on perpendicular magnetic anisotropy were investigated. The results show that the thickness of Pt underlayer has a great effect on the microstructure and perpendicular magnetic anisotropy of CoCr/Pt bilayers and (CoCr/Pt)20 multilayers.When the thickness of Pt underlayer increases, Pt(111) and CoCr(002) peaks of both CoCr/Pt bilayers and (CoCr/Pt)20 multilayers increase and the bilayer periodicity of the multilayers is improved. The effective magnetic anisotropy of (CoCr/Pt)20 multilayers with Pt underlayer was much larger than that of CoCr/Pt bilayers. The (CoCr/Pt)20 multilayers has a stronger perpendicular magnetic anisotropy than that of CoCr/Pt bilayers. This is ascribed to the interface magnetic anisotropy of the multilayers.

  15. Wet-chemical synthesis and properties of CoPt and CoPt3 alloy nanoparticles.

    Science.gov (United States)

    Frommen, Christoph; Rösner, Harald; Fenske, Dieter

    2002-10-01

    Surface-protected, air-stable nanoparticles of CoPt and CoPt3 were prepared by thermal decomposition/reduction of organometallic precursors with a long-chain aliphatic diol, also known as the polyol process. Particles 3 nm in diameter showed ferromagnetic behavior up to 350 K (Hc = 65 Oe at T = 300 K; Hc = 410 Oe at T = 5K) and underwent a disordering-ordering phase transformation after annealing that resulted in an increase in coercivity (Hc = 170 Oe at T = 300 K; Hc = 2000 Oe at T = 5 K).

  16. Syntheses and structural analyses of variable-stoichiometric Au-Pt-Ni carbonyl/phosphine clusters, Pt3(Pt(1-x)Ni(x))(AuPPh3)2(mu2-CO)4(CO)(PPh3)3 and Pt2(Pt(2-y)Ni(y))(AuPPh3)2(mu2-CO)4(CO)2(PPh3)2, with ligation-induced site-specific Pt/Ni substitutional disorder within butterfly-based Pt3(Pt(1-x)Ni(x))Au2 and Pt2(Pt(2-y)Ni(y))Au2 core-geometries.

    Science.gov (United States)

    de Silva, Namal; Nichiporuk, Rita V; Dahl, Lawrence F

    2006-05-21

    In ongoing attempts of directed synthesis of high-nuclearity Au-Pt carbonyl/phosphine clusters with [Ni6(CO)12]2- used as reducing agent and CO source, we have isolated and characterized two new closely related variable-stoichiometric trimetallic clusters, Pt3(Pt(1-x)Ni(x))(AuPPh3)2(mu2-CO)4(CO)(PPh3)3 (1) and Pt2(Pt(2-y)Ni(y))(AuPPh3)2(mu2-CO)4(CO)2(PPh3)2 (2). Their M4Au2 cores may be envisioned as substitutional disordered butterfly-based M4Au2 frameworks (M = Pt/Ni) formed by connections of the two basal M(B) atoms with both (Au-Au)-linked Au(PPh3) moieties. Based upon low-temperature CCD X-ray diffraction studies of eight crystals obtained from different samples, ligation-induced site-specific Pt/Ni substitutional disorder (involving formal insertion of Ni in place of Pt) in a given crystal was found to occur only at the one OC-attached basal M(B) site in 1 or at both OC-attached basal M(B) sites in 2 corresponding to a crystal composite of the Pt3(Pt(1-x)Ni(x))Au2 core in 1 or of the Pt2(Pt(2-y)Ni(y))Au2 core in 2; the Ph3P-attached M(B) site (M(B) = Pt) in 1 and two wingtip M(w) sites (M(w) = Pt) in 1 and 2 were not substitutionally disordered. The resulting variable stoichiometry of the M4Au2 core in 1 may be viewed as a crystal composite of two superimposed individual stereoisomers, Pt4(AuPPh3)2(mu2-CO)4(CO)(PPh3)3 (1a) and Pt3Ni(AuPPh3)2(mu2-CO)4(CO)(PPh3)3 (1b), in the averaged unit cell of a given crystal. Likewise, 2 represents the crystal-averaged composite of three individual stereoisomers, Pt4(AuPPh3)2(mu2-CO)4(CO)2(PPh3)2 (2a), Pt3Ni(AuPPh3)2(mu2-CO)4(CO)2(PPh3)2 (2b), and Pt2Ni2(AuPPh3)2(mu2-CO)4(CO)2(PPh3)2 (2c). Formal Ni substitution for Pt at only the basal M(B) site(s) in the four crystal composites each of 1 and 2 was found to vary widely from 17% to 79% Ni in 1 and from 21% to 95% Ni in 2. Nevertheless, reasonably close Pt/Ni occupancy factors were found within each of the four pairs of composite crystals selected from samples obtained from

  17. Synthesis of carbon-supported PtRh random alloy nanoparticles using electron beam irradiation reduction method

    Science.gov (United States)

    Matsuura, Yoshiyuki; Seino, Satoshi; Okazaki, Tomohisa; Akita, Tomoki; Nakagawa, Takashi; Yamamoto, Takao A.

    2016-05-01

    Bimetallic nanoparticle catalysts of PtRh supported on carbon were synthesized using an electron beam irradiation reduction method. The PtRh nanoparticle catalysts were composed of particles 2-3 nm in size, which were well dispersed on the surface of the carbon support nanoparticles. Analyses of X-ray diffraction and scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy revealed that the PtRh nanoparticles have a randomly alloyed structure. The lattice constant of the PtRh nanoparticles showed good correlation with Vegard's law. These results are explained by the radiochemical formation process of the PtRh nanoparticles. Catalytic activities of PtRh/C nanoparticles for ethanol oxidation reaction were found to be higher than those obtained with Pt/C.

  18. Theoretical elucidation of the competitive electro-oxidation mechanisms of formic acid on Pt(111).

    Science.gov (United States)

    Gao, Wang; Keith, John A; Anton, Josef; Jacob, Timo

    2010-12-29

    The mechanisms of formic acid (HCOOH) oxidation on Pt(111) under electrochemical conditions have been studied using density functional theory and then compared with the analogous gas-phase reaction. Results show that HCOOH oxidation under a water-covered surface behaves substantially differently than in the gas phase or using a solvation model involving only a few water molecules. Using these models, we evaluated the detailed reaction process, including energies and geometric structures of intermediates and transition states under the influence of different solvation models and electrode potentials. Our calculations indicate that this potential-dependent electrochemical oxidation proceeds via a multipath mechanism (involving both the adsorbed HCOOH and HCOO intermediates), a result succinctly rationalizing conflicting experimental observations. Moreover, this study highlights how subtle changes in electrochemical reaction environments can influence (electro)catalysis.

  19. PT AND PT/NI "NEEDLE" ELETROCATALYSTS ON CARBON NANOTUBES WITH HIGH ACTIVITY FOR THE ORR

    Energy Technology Data Exchange (ETDEWEB)

    Colon-Mercado, H.

    2011-11-10

    Platinum and platinum/nickel alloy electrocatalysts supported on graphitized (gCNT) or nitrogen doped carbon nanotubes (nCNT) are prepared and characterized. Pt deposition onto carbon nanotubes results in Pt 'needle' formations that are 3.5 nm in diameter and {approx}100 nm in length. Subsequent Ni deposition and heat treatment results in PtNi 'needles' with an increased diameter. All Pt and Pt/Ni materials were tested as electrocatalysts for the oxygen reduction reaction (ORR). The Pt and Pt/Ni catalysts showed excellent performance for the ORR, with the heat treated PtNi/gCNT (1.06 mA/cm{sup 2}) and PtNi/nCNT (0.664 mA/cm{sup 2}) showing the highest activity.

  20. High Incidence of Respiratory Involvement in a Cluster of Brucella suis-Infected Workers from a Pork Processing Plant in Argentina.

    Science.gov (United States)

    Wallach, J C; García, J L; Cardinali, P S; Seijo, A P; Benchetrit, A G; Echazarreta, S E; Garro, S L; Deodato, B; Baldi, P C

    2016-12-29

    Epidemiological and clinical aspects of Brucella suis infection in 17 workers from a pork processing plant in Argentina occurring between January 2014 and July 2015 are presented. All patients reported working 9 h daily without adequate personal protection garment. Blood cultures were positive for Brucella spp. in 14 of the 17 patients (82.3%). All isolates were identified as B. suis biovar 1. Although fever, sweats, asthenia, myalgia and hepatic involvement were the most frequent clinical manifestations, an unusually high incidence of respiratory involvement was found. From 13 patients in which chest radiography was performed, four (30%) had radiological abnormalities, including lobar pneumonia in two cases (one with pleural effusion) and interstitial involvement in other two. The high frequency of respiratory involvement in our series makes necessary to consider brucellosis in the differential diagnosis of respiratory diseases in pork processing plant employees.