Realistic Creativity Training for Innovation Practitioners: The Know-Recognize-React Model

DEFF Research Database (Denmark)

Valgeirsdóttir, Dagný; Onarheim, Balder

2017-01-01

As creativity becomes increasingly recognized as important raw material for innovation, the importance of identifying ways to increase practitioners’ creativity through rigorously designed creativity training programs is highlighted. Therefore we sat out to design a creativity training program sp...... the transdisciplinary study described in this paper. Co-creation was employed as a method to ensure the three layers of focus would be taken into consideration. The result is a program called Creative Awareness Training which is based on the new Know-Recognize-React model.......As creativity becomes increasingly recognized as important raw material for innovation, the importance of identifying ways to increase practitioners’ creativity through rigorously designed creativity training programs is highlighted. Therefore we sat out to design a creativity training program...

Cross-reacting and heterospecific monoclonal antibodies produced against arabis mosaic nepovirus.

Science.gov (United States)

Frison, E A; Stace-Smith, R

1992-10-01

Monoclonal antibodies (MAbs) were produced against arabis mosaic nepovirus (AMV). A hybridoma screening procedure was applied which involved the testing of culture supernatants, before the hybridomas were cloned to single cell lines, for their reaction with eight nepoviruses [AMV, cherry leafroll virus (CLRV), grapevine fanleaf virus (GFLV), peach rosette mosaic virus, raspberry ringspot virus (RRSV), tobacco ringspot virus, tomato black ring virus (TBRV) and tomato ringspot virus]. In addition to AMV-specific MAbs, this screening technique has allowed the selection of two cross-reacting MAbs: one reacting with AMV and GFLV, and one reacting with AMV and RRSV. This is the first report of MAbs cross-reacting with these nepoviruses. In addition, five heterospecific MAbs (HS-MAbs) could be selected: two reacting with RRSV, two with CLRV and one with TBRV. The usefulness of the screening technique that was applied for the selection of cross-reacting MAbs and HS-MAbs, and the potential use of such antibodies are discussed.

[A surface reacted layer study of titanium-zirconium alloy after dental casting].

Science.gov (United States)

Zhang, Y; Guo, T; Li, Z; Li, C

2000-10-01

To investigate the influence of the mold temperature on the surface reacted layer of Ti-Zr alloy castings. Ti-Zr alloy was casted into a mold which was made of a zircon (ZrO2.SiO2) for inner coating and a phosphate-bonded material for outer investing with a casting machine (China) designed as vacuum, pressure and centrifuge. At three mold temperatures (room temperature, 300 degrees C, 600 degrees C) the Ti-Zr alloy was casted separately. The surface roughness of the castings was calculated by instrument of smooth finish (China). From the surface to the inner part the Knoop hardness and thickness in reacted layer of Ti-Zr alloy casting was measured. The structure of the surface reacted layer was analysed by SEM. Elemental analyses of the interfacial zone of the casting was made by element line scanning observation. The surface roughness of the castings was increased significantly with the mold temperature increasing. At a higher mold temperature the Knoop hardness of the reactive layer was increased. At the three mold temperature the outmost surface was very hard, and microhardness data decreased rapidly where they reached constant values. The thickness was about 85 microns for castings at room temperature and 300 degrees C, 105 microns for castings at 600 degrees C. From the SEM micrograph of the Ti-Zr alloy casting, the surface reacted layer could be divided into three different layers. The first layer was called non-structure layer, which thickness was about 10 microns for room temperature group, 20 microns for 300 degrees C and 25 microns for 600 degrees C. The second layer was characterized by coarse-grained acicular crystal, which thickness was about 50 microns for three mold temperatures. The third layer was Ti-Zr alloy. The element line scanning showed non-structure layer with higher level of element of O, Al, Si and Zr, The higher the mold temperature during casting, the deeper the Si permeating and in the second layer the element Si could also be found

Numerical Investigation into CO Emission, O Depletion, and Thermal Decomposition in a Reacting Slab

Directory of Open Access Journals (Sweden)

O. D. Makinde

2011-01-01

Full Text Available The emission of carbon dioxide (CO2 is closely associated with oxygen (O2 depletion, and thermal decomposition in a reacting stockpile of combustible materials like fossil fuels (e.g., coal, oil, and natural gas. Moreover, it is understood that proper assessment of the emission levels provides a crucial reference point for other assessment tools like climate change indicators and mitigation strategies. In this paper, a nonlinear mathematical model for estimating the CO2 emission, O2 depletion, and thermal stability of a reacting slab is presented and tackled numerically using a semi-implicit finite-difference scheme. It is assumed that the slab surface is subjected to a symmetrical convective heat and mass exchange with the ambient. Both numerical and graphical results are presented and discussed quantitatively with respect to various parameters embedded in the problem.

Fungal decay resistance of wood reacted with phosphorus pentoxide-amine system

Science.gov (United States)

Hong-Lin Lee; George C. Chen; Roger M. Rowell

2004-01-01

Resistance of wood reacted in situ with phosphorus pentoxide-amine to the brown-rot fungus Gloeophyllum trabeum and white-rot fungus Trametes versicolor was examined. Wood reacted with either octyl, tribromo, or nitro derivatives were more resistant to both fungi. Threshold retention values of phosphoramide-reacted wood to white-rot fungus T. versicolor ranged from 2.9...

The REACT Project

DEFF Research Database (Denmark)

Bloch, Paul; Blystad, Astrid; Byskov, Jens

decisions; and the provision of leadership and the enforcement of conditions. REACT - "REsponse to ACcountable priority setting for Trust in health systems" is an EU-funded five-year intervention study, which started in 2006 testing the application and effects of the AFR approach in one district each...... selected disease and programme interventions and services, within general care and on health systems management. Efforts to improve health sector performance have not yet been satisfactory, and adequate and sustainable improvements in health outcomes have not been shown. Priority setting in health systems...... improvements to health systems performance discussed....

A constitutive theory of reacting electrolyte mixtures

Science.gov (United States)

Costa Reis, Martina; Wang, Yongqi; Bono Maurizio Sacchi Bassi, Adalberto

2013-11-01

A constitutive theory of reacting electrolyte mixtures is formulated. The intermolecular interactions among the constituents of the mixture are accounted for through additional freedom degrees to each constituent of the mixture. Balance equations for polar reacting continuum mixtures are accordingly formulated and a proper set of constitutive equations is derived with basis in the Müller-Liu formulation of the second law of thermodynamics. Moreover, the non-equilibrium and equilibrium responses of the reacting mixture are investigated in detail by emphasizing the inner and reactive structures of the medium. From the balance laws and constitutive relations, the effects of molecular structure of constituents upon the fluid flow are studied. It is also demonstrated that the local thermodynamic equilibrium state can be reached without imposing that the set of independent constitutive variables is time independent, neither spatially homogeneous nor null. The resulting constitutive relations presented throughout this work are of relevance to many practical applications, such as swelling of clays, developing of bio and polymeric membranes, and use of electrorheological fluids in industrial processes. The first author acknowledges financial support from National Counsel of Technological and Scientific Development (CNPq) and German Academic Exchange Service (DAAD).

Three-dimensional reacting shock–bubble interaction

NARCIS (Netherlands)

Diegelmann, Felix; Hickel, S.; Adams, Nikolaus A.

2017-01-01

We investigate a reacting shock–bubble interaction through three-dimensional numerical simulations with detailed chemistry. The convex shape of the bubble focuses the shock and generates regions of high pressure and temperature, which are sufficient to ignite the diluted stoichiometric

Characterization of forced response of density stratified reacting wake

Science.gov (United States)

Pawar, Samadhan A.; Sujith, Raman I.; Emerson, Benjamin; Lieuwen, Tim

2018-02-01

The hydrodynamic stability of a reacting wake depends primarily on the density ratio [i.e., ratio of unburnt gas density (ρu) to burnt gas density (ρb)] of the flow across the wake. The variation of the density ratio from high to low value, keeping ρ u / ρ b > 1 , transitions dynamical characteristics of the reacting wake from a linearly globally stable (or convectively unstable) to a globally unstable mode. In this paper, we propose a framework to analyze the effect of harmonic forcing on the deterministic and synchronization characteristics of reacting wakes. Using the recurrence quantification analysis of the forced wake response, we show that the deterministic behaviour of the reacting wake increases as the amplitude of forcing is increased. Furthermore, for different density ratios, we found that the synchronization of the top and bottom branches of the wake with the forcing signal is dependent on whether the mean frequency of the natural oscillations of the wake (fn) is lesser or greater than the frequency of external forcing (ff). We notice that the response of both branches (top and bottom) of the reacting wake to the external forcing is asymmetric and symmetric for the low and high density ratios, respectively. Furthermore, we characterize the phase-locking behaviour between the top and bottom branches of the wake for different values of density ratios. We observe that an increase in the density ratio results in a gradual decrease in the relative phase angle between the top and bottom branches of the wake, which leads to a change in the vortex shedding pattern from a sinuous (anti-phase) to a varicose (in-phase) mode of the oscillations.

Combining discrete equations method and upwind downwind-controlled splitting for non-reacting and reacting two-fluid computations

International Nuclear Information System (INIS)

Tang, K.

2012-01-01

When numerically investigating multiphase phenomena during severe accidents in a reactor system, characteristic lengths of the multi-fluid zone (non-reactive and reactive) are found to be much smaller than the volume of the reactor containment, which makes the direct modeling of the configuration hardly achievable. Alternatively, we propose to consider the physical multiphase mixture zone as an infinitely thin interface. Then, the reactive Riemann solver is inserted into the Reactive Discrete Equations Method (RDEM) to compute high speed combustion waves represented by discontinuous interfaces. An anti-diffusive approach is also coupled with RDEM to accurately simulate reactive interfaces. Increased robustness and efficiency when computing both multiphase interfaces and reacting flows are achieved thanks to an original upwind downwind-controlled splitting method (UDCS). UDCS is capable of accurately solving interfaces on multi-dimensional unstructured meshes, including reacting fronts for both deflagration and detonation configurations. (author)

Measurements of non-reacting and reacting flow fields of a liquid swirl flame burner

Science.gov (United States)

Chong, Cheng Tung; Hochgreb, Simone

2015-03-01

The understanding of the liquid fuel spray and flow field characteristics inside a combustor is crucial for designing a fuel efficient and low emission device. Characterisation of the flow field of a model gas turbine liquid swirl burner is performed by using a 2-D particle imaging velocimetry(PIV) system. The flow field pattern of an axial flow burner with a fixed swirl intensity is compared under confined and unconfined conditions, i.e., with and without the combustor wall. The effect of temperature on the main swirling air flow is investigated under open and non-reacting conditions. The result shows that axial and radial velocities increase as a result of decreased flow density and increased flow volume. The flow field of the main swirling flow with liquid fuel spray injection is compared to non-spray swirling flow. Introduction of liquid fuel spray changes the swirl air flow field at the burner outlet, where the radial velocity components increase for both open and confined environment. Under reacting condition, the enclosure generates a corner recirculation zone that intensifies the strength of radial velocity. The reverse flow and corner recirculation zone assists in stabilizing the flame by preheating the reactants. The flow field data can be used as validation target for swirl combustion modelling.

Sentinel Gap basalt reacted in a temperature gradient

International Nuclear Information System (INIS)

Charles, R.W.; Bayhurst, G.K.

1983-01-01

Six basalt prisms were reacted in a controlled temperature gradient hydrothermal circulation system for two months. The prisms were centered at 72, 119, 161, 209, 270, and 310 0 C. Total pressure was 1/3 kbar. All prisms showed large weight loss: 5.5% to 14.9%. The matrix micropegmatite and natural nontronitic alteration reacted readily to clays at all temperatures. The first four prisms were coated with a calcium smectite, and the last two prisms were covered with discrete patches of potassium-rich phengite and alkali feldspar. The results indicated that clays may act as adsorbers of various ions

Sentinel Gap basalt reacted in a temperature gradient

International Nuclear Information System (INIS)

Charles, R.W.; Bayhurst, G.K.

1982-01-01

Six basalt prisms were reacted in a controlled temperature gradient hydrothermal circulation system for two months. The prisms are centered at 72, 119, 161, 209, 270, and 310 0 C. Total pressure is 1/3 kbar. All prisms show large weight loss: 5.5% to 14.9%. The matrix micropegmatite and natural nontronitic alteration readily reacts to clays at all temperatures. The first four prisms are coated with a Ca-smectite while the last two prisms are covered with discrete patches of K rich phengite and alkali feldspar. The clays may act as adsorbers of various ions

Process for preparing coating materials

International Nuclear Information System (INIS)

Ryoke, Hideyasu; Kobayashi, Juichi; Kobayashi, Kei.

1972-01-01

A coating material curable with ionizing radiations or ultraviolet radiation can be prepared by reacting a compound (A) having one OH group and at least one α,β-ethylenic or allyl group with a polyisocyanate. (A) is a diester of a dicarboxylic acid. One of the ester groups may have a terminal α,β-ethylenic or allyl group and the other contains one OH and one α,β-ethylenic or allyl group. (A) is reacted with a polyisocyanate to yield an urethane. The latter may be diluted with a vinyl monomer. When exposed to a radiation, the coating material cures to give a film excellent in adhesion, impact strength and resistances to pollution, water and solvents. Dose of the ionizing radiation (α-, β-, γ-rays, electron beams) is 0.2-20 Mrad. In one example, 116 parts of 2-hydroxyethyl acrylate was reacted with 148 parts of phthalic anhydride and 142 parts of glycidyl methacrylate to give (A). (A) was reacted with 87 parts of tolylenediisocyanate. A metallic panel was coated with the coating material and cured with electron beams (5 Mrad). Pencil hardness was H, and gel fraction measured in acetone was above 97%. The coating was excellent in resistances to solvent and chemicals, impact strength and adhesion. (Kaichi, S.)

The need analysis of chemistry module based on REACT (relating, experiencing, applying, cooperating and transferring) to improve critical thinking ability

Science.gov (United States)

Tyffani, D. M.; Utomo, S. B.; Rahardjo, S. B.

2018-05-01

This research was aimed to find out how students’ need of chemistry module based REACT (Relating, Experiencing, Applying, Cooperating and Transferring) to improve students’ critical thinking ability. The subjects of this research was the studentsof XI grade in three school in even semester of academic year 2016-2017 that contained of 48 students of Senior High School 2 Bandar Lampung, 38 students of Senior High School 3 Bandar Lampung and 46 students of Senior High School 12 Bandar Lampung. The data was gathering used non-test method by using open questionnaire with 13 questions. The results showed that 84,84% of students stated that the development of chemistry module based REACT on colloid material is needed. The analysis of hand’s book was used aspects of critical thinking proposed by Facione (2011) are interpretation, analysis, evaluation, conclusion, and explanation. Based on the result of the analysis of hand’s book at Senior High School 12 Bandar Lampung for critical thinking in colloid material that indicate 50% indicator is appropriate, while for indicator of inference and explanation only 16,67% appropriate, then for indicator analysis and evaluation doesn’t have conformity. Based on the results of the analysis shows that the hand’s book used have not empowered critical thinking ability with maximum. The development of chemistry module on colloid material is needed to overcome the problem of hand’s book that hasn’t maximized critical thinking ability, then the development of module oriented to REACT learning model (Relating, Experiencing, Applying, Cooperating, and Transferring).

An experimental and numerical study of confined non-reacting and reacting turbulent jets to facilitate homogeneous combustion in industrial furnaces

Science.gov (United States)

Lee, Insu

Confined non-reacting turbulent jets are ideal for recirculating the hot flue gas back into the furnace from an external exhaust duct. Such jets are also used inside the furnace to internally entrain and recirculate the hot flue gas to preheat and dilute the reactants. Both internal and external implementation of confined turbulent jets increase the furnace thermal efficiency. For external implementation, depending on the circumstances, the exhaust gas flow may be co- or counter-flow relative to the jet flow. Inside the furnaces, fuel and air jets are injected separately. To create a condition which can facilitate near homogeneous combustion, these jets have to first mix with the burned gas inside the furnace and simultaneously being heated and diluted prior to combustion. Clearly, the combustion pattern and emissions from reacting confined turbulent jets are affected by jet interactions, mixing and entrainment of hot flue gas. In this work, the flow and mixing characteristics of a non-reacting and reacting confined turbulent jet are investigated experimentally and numerically. This work consists of two parts: (i) A study of flow and mixing characteristics of non-reacting confined turbulent jets with co- or counter-flowing exhaust/flue gas. Here the axial and radial distributions of temperature, velocity and NO concentration (used as a tracer gas) were measured. FLUENT was used to numerically simulate the experimental results. This work provides the basic understanding of the flow and mixing characteristics of confined turbulent jets and develops some design considerations for recirculating flue gas back into the furnace as expressed by the recirculation zone and the stagnation locations. (ii) Numerical calculations of near homogeneous combustion are performed for the existing furnace. The exact geometry of the furnace in the lab is used and the real dimensional boundary conditions are considered. The parameters such as air nozzle diameter (dair), fuel nozzle

ReACT!: An Interactive Educational Tool for AI Planning for Robotics

Science.gov (United States)

Dogmus, Zeynep; Erdem, Esra; Patogulu, Volkan

2015-01-01

This paper presents ReAct!, an interactive educational tool for artificial intelligence (AI) planning for robotics. ReAct! enables students to describe robots' actions and change in dynamic domains without first having to know about the syntactic and semantic details of the underlying formalism, and to solve planning problems using…

Continuum-Kinetic Hybrid Framework for Chemically Reacting Flows

Data.gov (United States)

National Aeronautics and Space Administration — Predictive modeling of chemically reacting flows is essential for the design and optimization of future hypersonic vehicles. During atmospheric re-entry, complex...

Fusion-reactor blanket-material safety-compatibility studies

International Nuclear Information System (INIS)

Jeppson, D.W.; Muhlestein, L.D.; Keough, R.F.; Cohen, S.

1982-11-01

Blanket material selection for fusion reactors is strongly influenced by the desire to minimize safety and environmental concerns. Blanket material safety compatibility studies are being conducted to identify and characterize blanket-coolant-material interactions under postulated reactor accident conditions. Recently completed scoping compatibility tests indicate that : (1) ternary oxides (LiAlO 2 , Li 2 ZrO 3 , Li 2 SiO 3 , Li 4 SiO 4 and LiTiO 3 ) at postulated blanket operating temperatures are compatible with water coolant, while liquid lithium and Li 7 Pb 2 alloy reactions with water generate heat, aerosol and hydrogen; (2) lithium oxide and Li 17 Pb 83 alloy react mildly with water requiring special precautions to control hydrogen release; (3) liquid lithium reacts substantially, while Li 17 Pb 83 alloy reacts mildly with concrete to produce hydrogen; and (4) liquid lithium-air reactions present some major safety concerns

Study of Transport and Micro-structural properties of Magnesium Di-Boride Strand under react and bend mode and bend and react mode

International Nuclear Information System (INIS)

Kundu, Ananya; Kumar Das, Subrat; Bano, Anees; Pradhan, Subrata

2017-01-01

I-V characterization of commercial multi-filamentary Magnesium Di-Boride (MgB 2 ) wire of diameter 0.83 mm were studied in Cryocooler at self-field I-V characterization system under both react and bend mode and bend and react mode for a range of temperature 6 K - 25 K. This study is of practical technical relevance where the heat treatment of the superconducting wire makes the wire less flexible for winding in magnet and in other applications. In the present work the bending diameter was varied from 40 mm to 20 mm and for each case critical current (I c ) of the strand is measured for above range of temperature. A customized sample holder is fabricated and thermally anchored with the 2 nd cold stage of Cryocooler. It is observed from the measurement that the strand is more susceptible to degradation for react and bend cases. The transport measurement of the strand was accompanied by SEM analyses of bend samples. Also the tensile strength of the raw strands and the heat treated strands were carried out at room temperature in Universal Testing Machine (UTM) to have an estimate about the limiting winding tension value during magnet fabrication. (paper)

Demonstration of Hybrid DSMC-CFD Capability for Nonequilibrium Reacting Flow

Science.gov (United States)

2018-02-09

AFRL-RV-PS- TR-2018-0056 AFRL-RV-PS- TR-2018-0056 DEMONSTRATION OF HYBRID DSMC-CFD CAPABILITY FOR NONEQUILIBRIUM REACTING FLOW Thomas E...4. TITLE AND SUBTITLE Demonstration of Hybrid DSMC-CFD Capability for Nonequilibrium Reacting Flow 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9453-17-1...simulation codes. The models are based on new ab-intio rate data obtained using state -of-the-art potential energy surfaces for air species. A probability

An experimental study on downstream of the transition of the chemically reacting liquid round free jet

International Nuclear Information System (INIS)

Hong, S.D.; Sugii, Y.; Okamoto, K.; Madarame, H.

2002-01-01

An experimental study was conducted on the chemically reacting liquid round free jet, Laser Induced Fluorescence (LIF) technique was adopted to evaluate the diffusion width of the jet into liquid streams. In the fluid engineering, it is very important to evaluate the characteristics of reacting jet for the safety of the nuclear reactor. In this study, the jet profile of downstream region far away from the transition point was evaluated, providing comparisons between reacting and non-reacting jet case. The concentration of the jet solution was varied from 0.01 mol/L to 0.5 mol/L in reacting cases. In the downstream far away from the transition point, the jet profiles between reacting cases and non-reacting cases were visualized quite different. It was concluded that the chemical reaction affects the momentum diffusion of the jet in the downstream region. (author)

Effect of skin barrier disruption on immune responses to topically applied cross-reacting material, CRM(197), of diphtheria toxin.

Science.gov (United States)

Godefroy, S; Peyre, M; Garcia, N; Muller, S; Sesardic, D; Partidos, C D

2005-08-01

The high accessibility of the skin and the presence of immunocompetent cells in the epidermis makes this surface an attractive route for needle-free administration of vaccines. However, the lining of the skin by the stratum corneum is a major obstacle to vaccine delivery. In this study we examined the effect of skin barrier disruption on the immune responses to the cross-reacting material CRM(197), a nontoxic mutant of diphtheria toxin (DTx) that is considered as a vaccine candidate. Application of CRM(197), together with cholera toxin (CT), onto the tape-stripped skin of mice elicited antibody responses that had anti-DTx neutralizing activity. Vaccine delivery onto mildly ablated skin or intact skin did not elicit any detectable anti-CRM(197) antibodies. Mice immunized with CRM(197) alone onto the tape-stripped skin mounted a vigorous antigen-specific proliferative response. In contrast, the induction of cellular immunity after CRM(197) deposition onto mildly ablated or intact skin was adjuvant dependent. Furthermore, epidermal cells were activated and underwent apoptosis that was more pronounced when the stratum corneum was removed by tape stripping. Overall, these findings highlight the potential for transcutaneous delivery of CRM(197) and establish a correlation between the degree of barrier disruption and levels of antigen-specific immune responses. Moreover, these results provide the first evidence that the development of a transcutaneous immunization strategy for diphtheria, based on simple and practical methods to disrupt the skin barrier, is feasible.

Improving Resilience to Emergencies through Advanced Cyber Technologies: the I-REACT project

Directory of Open Access Journals (Sweden)

Claudia Maltoni

2017-08-01

be equipped with essential tools for early warning and response. At the same time, private companies could leverage specific set of I-REACT components to improve their business, when linked to disaster management. Overall, I-REACT aims to be a European-wide contribution to build more secure and resilient societies to disasters.

KEEFEKTIFAN STRATEGI REACT DITINJAU DARI PRESTASI BELAJAR, KEMAMPUAN PENYELESAIAN MASALAH, KONEKSI MATEMATIS, SELF EFFICACY

Directory of Open Access Journals (Sweden)

Runtyani Irjayanti Putri

2015-11-01

Full Text Available Penelitian ini bertujuan untuk: (1 mendeskripsikan keefektifan strategi pembelajaran REACT pada pembelajaran turunan fungsi ditinjau dari prestasi belajar matematika, kemampuan penyelesaian masalah matematis, kemampuan koneksi matematis, dan Self efficacy siswa SMA Negeri 4 Magelang, (2 menentukan strategi pembelajaran yang lebih efektif diantara strategi REACT dan pembelajaran konvensional pada pembelajaran turunan fungsi ditinjau dari aspek prestasi belajar matematika, kemampuan penyelesaian masalah matematis, kemampuan koneksi matematis, dan Self efficacy siswa SMA Negeri 4 Magelang. Penelitian ini adalah penelitian quasi experiment. Teknik pengumpulan data yang digunakan adalah teknik tes dan nontes. Teknik analisis data yang digunakan adalah uji one sample t-test, uji T2 Hotelling’s, dan uji t-Bonferroni. Hasil penelitian menunjukkan bahwa: (1 strategi pembelajaran REACT efektif pada pembelajaran turunan fungsi ditinjau dari prestasi belajar matematika, kemampuan penyelesaian masalah matematis, kemampuan koneksi matematis, dan Self efficacy siswa SMA Negeri 4 Magelang, dan (2 strategi pembelajaran REACT lebih efektif daripada pembelajaran konvensional pada pembelajaran turunan fungsi ditinjau dari aspek prestasi belajar matematika, kemampuan penyelesaian masalah matematis, kemampuan koneksi matematis, dan Self efficacy siswa SMA Negeri 4 Magelang. Kata Kunci: strategi REACT, prestasi belajar, kemampuan penyelesaian masalah matematis, kemampuan koneksi matematis, dan Self efficacy siswa SMA   THE EFFECTIVENESS OF REACT STRATEGY VIEWED FROM LEARNING ACHIEVEMENT, PROBLEM SOLVING ABILITY, MATHEMATICAL CONNECTION, SELF EFFICACY Abstract The aims of this study are to: (1 to describe the effectiveness of the REACT strategy viewed from Mathematics Learning Achievement, Mathematics Problem Solving Ability, Mathematics Connection Ability, and Student Self efficacy of State Senior High School 4 Magelang Students, and (2 determine a more effective

Process to separate alkali metal salts from alkali metal reacted hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Gordon, John Howard; Alvare, Javier; Larsen, Dennis; Killpack, Jeff

2017-06-27

A process to facilitate gravimetric separation of alkali metal salts, such as alkali metal sulfides and polysulfides, from alkali metal reacted hydrocarbons. The disclosed process is part of a method of upgrading a hydrocarbon feedstock by removing heteroatoms and/or one or more heavy metals from the hydrocarbon feedstock composition. This method reacts the oil feedstock with an alkali metal and an upgradant hydrocarbon. The alkali metal reacts with a portion of the heteroatoms and/or one or more heavy metals to form an inorganic phase containing alkali metal salts and reduced heavy metals, and an upgraded hydrocarbon feedstock. The inorganic phase may be gravimetrically separated from the upgraded hydrocarbon feedstock after mixing at a temperature between about 350.degree. C. to 400.degree. C. for a time period between about 15 minutes and 2 hours.

Prediction of reacting atoms for the major biotransformation reactions of organic xenobiotics.

Science.gov (United States)

Rudik, Anastasia V; Dmitriev, Alexander V; Lagunin, Alexey A; Filimonov, Dmitry A; Poroikov, Vladimir V

2016-01-01

The knowledge of drug metabolite structures is essential at the early stage of drug discovery to understand the potential liabilities and risks connected with biotransformation. The determination of the site of a molecule at which a particular metabolic reaction occurs could be used as a starting point for metabolite identification. The prediction of the site of metabolism does not always correspond to the particular atom that is modified by the enzyme but rather is often associated with a group of atoms. To overcome this problem, we propose to operate with the term "reacting atom", corresponding to a single atom in the substrate that is modified during the biotransformation reaction. The prediction of the reacting atom(s) in a molecule for the major classes of biotransformation reactions is necessary to generate drug metabolites. Substrates of the major human cytochromes P450 and UDP-glucuronosyltransferases from the Biovia Metabolite database were divided into nine groups according to their reaction classes, which are aliphatic and aromatic hydroxylation, N- and O-glucuronidation, N-, S- and C-oxidation, and N- and O-dealkylation. Each training set consists of positive and negative examples of structures with one labelled atom. In the positive examples, the labelled atom is the reacting atom of a particular reaction that changed adjacency. Negative examples represent non-reacting atoms of a particular reaction. We used Labelled Multilevel Neighbourhoods of Atoms descriptors for the designation of reacting atoms. A Bayesian-like algorithm was applied to estimate the structure-activity relationships. The average invariant accuracy of prediction obtained in leave-one-out and 20-fold cross-validation procedures for five human isoforms of cytochrome P450 and all isoforms of UDP-glucuronosyltransferase varies from 0.86 to 0.99 (0.96 on average). We report that reacting atoms may be predicted with reasonable accuracy for the major classes of metabolic reactions

Double Shock Experiments Performed at -55°C on LX-17 with Reactive Flow Modeling to Understand the Reacted Equation of State

Science.gov (United States)

Dehaven, Martin R.; Vandersall, Kevin S.; Strickland, Shawn L.; Fried, Laurence E.; Tarver, Craig M.

2017-06-01

Experiments were performed at -55°C to measure the reacted state of LX-17 (92.5% TATB and 7.5% Kel-F by weight) using a double shock technique using two flyer materials (with known properties) mounted on a projectile that send an initial shock through the material close to the Chapman-Jouguet (CJ) state followed by a second shock at a higher magnitude into the detonated material. Information on the reacted state is obtained by measuring the relative timing and magnitude of the first and second shock waves. The LX-17 detonation reaction zone profiles plus the arrival times and amplitudes of reflected shocks in LX-17 detonation reaction products were measured using Photonic Doppler Velocimetry (PDV) probes and an aluminum foil coated LiF window. A discussion of this work will include a comparison to prior work at ambient temperature, the experimental parameters, velocimetry profiles, data interpretation, reactive CHEETAH and Ignition and Growth modeling, as well as detail on possible future experiments. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Numerical simulation of reacting and non-reacting flow in a combustion chamber; Numerisk simulering av reagerande och icke-reagerande stroemning i en braennkammare

Energy Technology Data Exchange (ETDEWEB)

Borg, A.; Revstedt, J.

1996-04-01

The purpose of this work has been to do a preliminary study of how well numerical calculations with different turbulence models can predict the flow and temperature fields of a strongly swirling and combusting flow in an experimental combustion chamber and to see which parameters in the mathematical model are the most important. The combustion chamber on which we have done the calculations is called Validation Rig II and was designed by Volvo Aero Corporation. The main part of the study has been carried out on a non-reacting flow but some work has also been done on reacting flow. In most cases it has not been meaningful to compare the calculations with the measurements because they differ quite a lot from each other. For the non-reacting case the following investigations have been made: * How the solution differs for different turbulence models, * The solutions sensitivity to inlet boundary conditions, * How different types of leakage disturb the flow, and * The difference in results between two different CFD-codes, the commercial code CFDS-Flow3D and a code developed at the department of fluid mechanics. For the reacting cases we have studied the influence of: * one or two reaction steps, * the effects of a change in reaction rate, * the influence of thermal radiation, and * the effects of changing the boundary conditions for temperature on the walls. The results from these calculations show that the inlet turbulence intensity has very little effect on the values of the turbulent quantities as well as the velocity profiles at the outlet. Changing the turbulence model or the outlet boundary conditions gives some change in velocity profiles at the outlet but only marginal effects on the swirl number. 21 refs, 54 figs, 19 tabs

Large eddy simulation and direct numerical simulation of high speed turbulent reacting flows

Science.gov (United States)

Adumitroaie, V.; Frankel, S. H.; Madnia, C. K.; Givi, P.

The objective of this research is to make use of Large Eddy Simulation (LES) and Direct Numerical Simulation (DNS) for the computational analyses of high speed reacting flows. Our efforts in the first phase of this research conducted within the past three years have been directed in several issues pertaining to intricate physics of turbulent reacting flows. In our previous 5 semi-annual reports submitted to NASA LaRC, as well as several technical papers in archival journals, the results of our investigations have been fully described. In this progress report which is different in format as compared to our previous documents, we focus only on the issue of LES. The reason for doing so is that LES is the primary issue of interest to our Technical Monitor and that our other findings were needed to support the activities conducted under this prime issue. The outcomes of our related investigations, nevertheless, are included in the appendices accompanying this report. The relevance of the materials in these appendices are, therefore, discussed only briefly within the body of the report. Here, results are presented of a priori and a posterior analyses for validity assessments of assumed Probability Density Function (PDF) methods as potential subgrid scale (SGS) closures for LES of turbulent reacting flows. Simple non-premixed reacting systems involving an isothermal reaction of the type A + B yields Products under both chemical equilibrium and non-equilibrium conditions are considered. A priori analyses are conducted of a homogeneous box flow, and a spatially developing planar mixing layer to investigate the performance of the Pearson Family of PDF's as SGS models. A posteriori analyses are conducted of the mixing layer using a hybrid one-equation Smagorinsky/PDF SGS closure. The Smagorinsky closure augmented by the solution of the subgrid turbulent kinetic energy (TKE) equation is employed to account for hydrodynamic fluctuations, and the PDF is employed for modeling the

Comparison of improved finite-difference WENO schemes for the implicit large eddy simulation of turbulent non-reacting and reacting high-speed shear flows

International Nuclear Information System (INIS)

Zhao, S.; Lardjane, N.; Fedioun, I.

2014-01-01

Improved WENO schemes, Z, M, and their combination MZ, originally designed to capture sharper discontinuities than the classical fifth order Jiang-Shu scheme does, are evaluated for the purpose of implicit large eddy simulation of free shear flows. 1D Fourier analysis of errors reveals the built-in filter and dissipative properties of the schemes, which are subsequently applied to the canonical Rayleigh-Taylor and Taylor-Green flows. Large eddy simulations of a transonic non-reacting and a supersonic reacting air/H2 jets are then performed at resolution 128 * 128 * 512, showing no significant difference in the flow statistics. However, the computational time varies from one scheme to the other, the Z scheme providing the smaller wall-time due to larger allowed time steps. (authors)

Computation of turbulent reacting flow in a solid-propellant ducted rocket

Science.gov (United States)

Chao, Yei-Chin; Chou, Wen-Fuh; Liu, Sheng-Shyang

1995-05-01

A mathematical model for computation of turbulent reacting flows is developed under general curvilinear coordinate systems. An adaptive, streamline grid system is generated to deal with the complex flow structures in a multiple-inlet solid-propellant ducted rocket (SDR) combustor. General tensor representations of the k-epsilon and algebraic stress (ASM) turbulence models are derived in terms of contravariant velocity components, and modification caused by the effects of compressible turbulence is also included in the modeling. The clipped Gaussian probability density function is incorporated in the combustion model to account for fluctuations of properties. Validation of the above modeling is first examined by studying mixing and reacting characteristics in a confined coaxial-jet problem. This is followed by study of nonreacting and reacting SDR combustor flows. The results show that Gibson and Launder's ASM incorporated with Sarkar's modification for compressible turbulence effects based on the general curvilinear coordinate systems yields the most satisfactory prediction for this complicated SDR flowfield.

Chemical digestion of low level nuclear solid waste material

International Nuclear Information System (INIS)

Cooley, C.R.; Lerch, R.E.

1976-01-01

A chemical digestion for treatment of low level combustible nuclear solid waste material is provided and comprises reacting the solid waste material with concentrated sulfuric acid at a temperature within the range of 230 0 --300 0 C and simultaneously and/or thereafter contacting the reacting mixture with concentrated nitric acid or nitrogen dioxide. In a special embodiment spent ion exchange resins are converted by this chemical digestion to noncombustible gases and a low volume noncombustible residue. 6 claims, no drawings

Nb3Sn dipole magnet reacted after winding

International Nuclear Information System (INIS)

Taylor, C.; Scanlan, R.; Peters, C.; Wolgast, R.; Gilbert, W.; Hassenzahl, W.; Meuser, R.; Rechen, J.

1984-09-01

A 5 cm bore dia., 1-m-long dipole model magnet was constructed by winding un-reacted cable, followed by reaction and epoxy-impregnation. Experience and test results are described on the 1.7 mm dia. internal-tin wire, the eleven-strand flattened cable, fiberglass insulation, and construction of the magnet. Each half of the magnet has two double-pancake-type windings that were reacted in a single operation. The two double-pancakes were then separately vacuum impregnated after soldering the flexible Nb-Ti leads to the Nb 3 Sn conductors. No iron flux return yoke was used. In initial tests a central field of 8.0 T was reached at 4.4 K. However, evidence from training behavior, and 1.8 K tests indicate that premature quenching, rather than critical current of the cable, limited the field intensity. The magnet was reassembled and more rigidly clamped; additional test results are reported

REAC/TS radiation accident registry. Update of accidents in the United States

International Nuclear Information System (INIS)

Ricks, R.C.; Berger, M.E.; Holloway, E.C.; Goans, R.E.

2000-01-01

Serious injury due to ionizing radiation is a rare occurrence. From 1944 to the present, 243 US accidents meeting dose criteria for classification as serious are documented in the REAC/TS Registry. Thirty individuals have lost their lives in radiation accidents in the United States. The Registry is part of the overall REAC/TS program providing 24-hour direct or consultative assistance regarding medical and heath physics problems associated with radiation accidents in local, national, and international incidents. The REAC/TS Registry serves as a repository of medically important information documenting the consequences of these accidents. Registry data are gathered from various sources. These include reports from the World Heath Organization (WHO), International Atomic Energy Agency (IAEA), US Nuclear Regulatory Commission (US NRC), state radiological health departments, medical/health physics literature, personal communication, the Internet, and most frequently, from calls for medical assistance to REAC/TS, as part of our 24-hour medical assistance program. The REAC/TS Registry for documentation of radiation accidents serves several useful purposes: 1) weaknesses in design, safety practices, training or control can be identified, and trends noted; 2) information regarding the medical consequences of injuries and the efficacy of treatment protocols is available to the treating physician; and 3) Registry case studies serve as valuable teaching tools. This presentation will review and summarize data on the US radiation accidents including their classification by device, accident circumstances, and frequency by respective states. Data regarding accidents with fatal outcomes will be reviewed. The inclusion of Registry data in the IAEA's International Reporting System of Radiation Events (RADEV) will also be discussed. (author)

A stochastic model of particle dispersion in turbulent reacting gaseous environments

Science.gov (United States)

Sun, Guangyuan; Lignell, David; Hewson, John

2012-11-01

We are performing fundamental studies of dispersive transport and time-temperature histories of Lagrangian particles in turbulent reacting flows. The particle-flow statistics including the full particle temperature PDF are of interest. A challenge in modeling particle motions is the accurate prediction of fine-scale aerosol-fluid interactions. A computationally affordable stochastic modeling approach, one-dimensional turbulence (ODT), is a proven method that captures the full range of length and time scales, and provides detailed statistics of fine-scale turbulent-particle mixing and transport. Limited results of particle transport in ODT have been reported in non-reacting flow. Here, we extend ODT to particle transport in reacting flow. The results of particle transport in three flow configurations are presented: channel flow, homogeneous isotropic turbulence, and jet flames. We investigate the functional dependence of the statistics of particle-flow interactions including (1) parametric study with varying temperatures, Reynolds numbers, and particle Stokes numbers; (2) particle temperature histories and PDFs; (3) time scale and the sensitivity of initial and boundary conditions. Flow statistics are compared to both experimental measurements and DNS data.

Motivation, procedures and aims of reacting plasma experiments

International Nuclear Information System (INIS)

Miyahara, Akira

1982-01-01

A project of reacting plasma experiment (R-project) was proposed at the Institute of Plasma Physics (IPP), Nagoya University. It is necessary to bridge plasma physics and fusion engineering by means of a messenger wire like burning plasma experiment. This is a motivation of the R-project. The university linkage organization of Japan for fusion engineering category carried out a lot of contribution to R-tokamak design. The project consists of four items, namely, R-tokamak design, research and development (R and D), site and facilities, and international collaboration. The phase 1 experiment (R 1 - phase) corresponds to burning plasma experiment without D + T fuel, while the phase-2 experiment (R 2 -phase) with D + T fuel. One reference design was finished. Intensive efforts have been carried out by the R and D team on the following items, wall material, vacuum system, tritium system, neutronics, remote control system, pulsed superconducting magnet development, negative ion source, and alpha-particle diagnostics. The problems concerning site and major facilities are also important, because tritium handling, neutron and gamma-ray sky shines and the activation of devices cause impact to surrounding area. The aims of burning plasma experiment are to enter tritium into the fusion device, and to study burning plasma physics. (Kato, T.)

Calcination of calcium acetate and calcium magnesium acetate: effect of the reacting atmosphere

Energy Technology Data Exchange (ETDEWEB)

Adanez, J.; Diego, L.F. de; Garcia-Labiano, F. [Instituto de Carboquimica, Zaragoza (Spain). Dept. of Energy and Environment

1999-04-01

The calcination process of the calcium acetate (CA) and calcium magnesium acetate (CMA) was investigated as a previous step for coal gas desulfurisation during sorbent injection at high temperatures because the excellent results demonstrated by these sorbents as sulfur removal agents both in combustion and gasification processes. As pore structure developed during calcination is one of the most important characteristics of the sorbent related with the later reaction with the gaseous pollutants, several calcination tests were conducted in a drop tube reactor at temperatures from 700{degree}C to 1100{degree}C, and residence times from 0.8 to 2.4 s. Four different gas atmospheres were used for comparative purposes: inert, oxidising, reducing, and non-calcining (pure CO{sub 2}). Despite the advantage of the high porous cenospheric structure developed by these sorbents during their injection at high temperature, calcination of the CaCO{sub 3} was not complete even at the longest residence time, 2.4 s, and the highest temperature, 1100{degree}C, tested. An important effect of the reacting atmosphere on the calcination conversion and on the sorbent pore structure was detected. The CO{sub 2} concentration around the particle, both that fed in the reacting gases or that generated by organic material combustion, seems to be responsible for the final calcination conversions obtained in each case, also affecting the sintering suffered by the sorbents. 19 refs., 10 figs.

Simultaneous Temperature and Velocity Diagnostic for Reacting Flows, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — A diagnostic technique is proposed for measuring temperature and velocity simultaneously in a high temperature reacting flow for aiding research in propulsion. The...

Developing Dynamic Single Page Web Applications Using Meteor : Comparing JavaScript Frameworks: Blaze and React

OpenAIRE

Yetayeh, Asabeneh

2017-01-01

This paper studies Meteor which is a JavaScript full-stack framework to develop interactive single page web applications. Meteor allows building web applications entirely in JavaScript. Meteor uses Blaze, React or AngularJS as a view layer and Node.js and MongoDB as a back-end. The main purpose of this study is to compare the performance of Blaze and React. A multi-user Blaze and React web applications with similar HTML and CSS were developed. Both applications were deployed on Heroku’s w...

A model for reaction rates in turbulent reacting flows

Science.gov (United States)

Chinitz, W.; Evans, J. S.

1984-01-01

To account for the turbulent temperature and species-concentration fluctuations, a model is presented on the effects of chemical reaction rates in computer analyses of turbulent reacting flows. The model results in two parameters which multiply the terms in the reaction-rate equations. For these two parameters, graphs are presented as functions of the mean values and intensity of the turbulent fluctuations of the temperature and species concentrations. These graphs will facilitate incorporation of the model into existing computer programs which describe turbulent reacting flows. When the model was used in a two-dimensional parabolic-flow computer code to predict the behavior of an experimental, supersonic hydrogen jet burning in air, some improvement in agreement with the experimental data was obtained in the far field in the region near the jet centerline. Recommendations are included for further improvement of the model and for additional comparisons with experimental data.

Different event-related patterns of gamma-band power in brain waves of fast- and slow-reacting subjects.

Science.gov (United States)

Jokeit, H; Makeig, S

1994-01-01

Fast- and slow-reacting subjects exhibit different patterns of gamma-band electroencephalogram (EEG) activity when responding as quickly as possible to auditory stimuli. This result appears to confirm long-standing speculations of Wundt that fast- and slow-reacting subjects produce speeded reactions in different ways and demonstrates that analysis of event-related changes in the amplitude of EEG activity recorded from the human scalp can reveal information about event-related brain processes unavailable using event-related potential measures. Time-varying spectral power in a selected (35- to 43-Hz) gamma frequency band was averaged across trials in two experimental conditions: passive listening and speeded reacting to binaural clicks, forming 40-Hz event-related spectral responses. Factor analysis of between-subject event-related spectral response differences split subjects into two near-equal groups composed of faster- and slower-reacting subjects. In faster-reacting subjects, 40-Hz power peaked near 200 ms and 400 ms poststimulus in the react condition, whereas in slower-reacting subjects, 40-Hz power just before stimulus delivery was larger in the react condition. These group differences were preserved in separate averages of relatively long and short reaction-time epochs for each group. gamma-band (20-60 Hz)-filtered event-related potential response averages did not differ between the two groups or conditions. Because of this and because gamma-band power in the auditory event-related potential is small compared with the EEG, the observed event-related spectral response features must represent gamma-band EEG activity reliably induced by, but not phase-locked to, experimental stimuli or events. PMID:8022783

Prevalence of Allergy to Natural Rubber Latex and Potential Cross Reacting Food in Operation Room Staff in Shiraz Hospitals -2006

OpenAIRE

H Nabavizade; R Amin

2007-01-01

Introduction & Objective: Allergic reactions to natural rubber latex have increased during past 10 years especially among health care workers and patients with high exposure to latex allergens. Allergic reaction to latex is related to many diseases like occupational asthma. This study was performed to determine the prevalence of allergy to natural rubber latex and potential cross reacting food in operation room staff in Shiraz hospitals. Materials & Methods: In this cross-sectional descr...

Study of subgrid-scale velocity models for reacting and nonreacting flows

Science.gov (United States)

Langella, I.; Doan, N. A. K.; Swaminathan, N.; Pope, S. B.

2018-05-01

A study is conducted to identify advantages and limitations of existing large-eddy simulation (LES) closures for the subgrid-scale (SGS) kinetic energy using a database of direct numerical simulations (DNS). The analysis is conducted for both reacting and nonreacting flows, different turbulence conditions, and various filter sizes. A model, based on dissipation and diffusion of momentum (LD-D model), is proposed in this paper based on the observed behavior of four existing models. Our model shows the best overall agreements with DNS statistics. Two main investigations are conducted for both reacting and nonreacting flows: (i) an investigation on the robustness of the model constants, showing that commonly used constants lead to a severe underestimation of the SGS kinetic energy and enlightening their dependence on Reynolds number and filter size; and (ii) an investigation on the statistical behavior of the SGS closures, which suggests that the dissipation of momentum is the key parameter to be considered in such closures and that dilatation effect is important and must be captured correctly in reacting flows. Additional properties of SGS kinetic energy modeling are identified and discussed.

Effects of Fusion Tack Welds on Self-Reacting Friction Stir Welds

Science.gov (United States)

Nunes, A. C., Jr.; Pendleton, M. L.; Brooke, S. A.; Russell, C. K.

2012-01-01

In order to know whether fusion tack welds would affect the strength of self-reacting friction stir seam welds in 2195-T87 aluminum alloy, the fracture stresses of 144 tensile test coupons cut from 24 welded panels containing segments of friction stir welds were measured. Each of the panels was welded under unique processing conditions. A measure of the effect of the tack welds for each panel was devised. An analysis of the measures of the tack weld effect supported the hypothesis that fusion tack welds do not affect the strength of self-reacting friction stir welds to a 5% level of confidence.

Direct numerical simulations of reacting flows with detailed chemistry using many-core/GPU acceleration

KAUST Repository

Herná ndez Pé rez, Francisco E.; Mukhadiyev, Nurzhan; Xu, Xiao; Sow, Aliou; Lee, Bok Jik; Sankaran, Ramanan; Im, Hong G.

2018-01-01

A new direct numerical simulation (DNS) code for multi-component gaseous reacting flows has been developed at KAUST, with the state-of-the-art programming model for next generation high performance computing platforms. The code, named KAUST Adaptive Reacting Flows Solver (KARFS), employs the MPI+X programming, and relies on Kokkos for “X” for performance portability to multi-core, many-core and GPUs, providing innovative software development while maintaining backward compatibility with established parallel models and legacy code. The capability and potential of KARFS to perform DNS of reacting flows with large, detailed reaction mechanisms is demonstrated with various model problems involving ignition and turbulent flame propagations with varying degrees of chemical complexities.

Direct numerical simulations of reacting flows with detailed chemistry using many-core/GPU acceleration

KAUST Repository

Hernández Pérez, Francisco E.

2018-03-29

A new direct numerical simulation (DNS) code for multi-component gaseous reacting flows has been developed at KAUST, with the state-of-the-art programming model for next generation high performance computing platforms. The code, named KAUST Adaptive Reacting Flows Solver (KARFS), employs the MPI+X programming, and relies on Kokkos for “X” for performance portability to multi-core, many-core and GPUs, providing innovative software development while maintaining backward compatibility with established parallel models and legacy code. The capability and potential of KARFS to perform DNS of reacting flows with large, detailed reaction mechanisms is demonstrated with various model problems involving ignition and turbulent flame propagations with varying degrees of chemical complexities.

Birefringence characteristics in sperm heads allow for the selection of reacted spermatozoa for intracytoplasmic sperm injection.

Science.gov (United States)

Gianaroli, Luca; Magli, M Cristina; Ferraretti, Anna P; Crippa, Andor; Lappi, Michela; Capitani, Serena; Baccetti, Baccio

2010-02-01

To verify clinical outcome after injection of spermatozoa that have undergone the acrosome reaction (reacted spermatozoa) vs. those still having an intact acrosome (nonreacted spermatozoa). Prospective, randomized study. Reproductive Medicine Unit, Italian Society for the Study of Reproductive Medicine, Bologna, Italy. According to a prospective randomization including 71 couples with severe male factor infertility, intracytoplasmic sperm injection (ICSI) was performed under polarized light that permitted analysis of the pattern of birefringence in the sperm head. Twenty-three patients had their oocytes injected with reacted spermatozoa, 26 patient's oocytes were injected with nonreacted spermatozoa, and in 22 patients both reacted and nonreacted spermatozoa were injected. Intracytoplasmic sperm injection was performed under polarized light to selectively inject acrosome-reacted and acrosome-nonreacted spermatozoa. Rates of fertilization, cleavage, pregnancy, implantation, and ongoing implantation. There was no effect on the fertilizing capacity and embryo development of either type of sperm, whereas the implantation rate was higher in oocytes injected with reacted spermatozoa (39.0%) vs. those injected with nonreacted spermatozoa (8.6%). The implantation rate was 24.4% in the group injected with both reacted and nonreacted spermatozoa. The delivery rate per cycle followed the same trend. Spermatozoa that have undergone the acrosome reaction seem to be more prone to supporting the development of viable ICSI embryos. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Second law analysis of a reacting temperature dependent viscous ...

African Journals Online (AJOL)

In this paper, entropy generation during the flow of a reacting viscous fluid through an inclined Channel with isothermal walls are investigated. The coupled energy and momentum equations were solved numerically. Previous results in literature (Adesanya et al 2006 [[17]) showed both velocity and temperature have two ...

Differing Event-Related Patterns of Gamma-Band Power in Brain Waves of Fast- and Slow-Reacting Subjects

Science.gov (United States)

1994-05-01

Wilhelm Wundt proposed that there are two types of subjects in sim- ple RT experiments: fast-reacting subjects, who respond before they fully...quickly as possible to auditory stimuli. This result appears to confirm long-standing speculations of Wundt that fast- and slow-reacting subjects...accord with the hypothesis of Wundt and others that slower ("sensorial") responders wait to fully perceive a stimulus and then react to their perception

Cement materials for cesium and iodine confinement

International Nuclear Information System (INIS)

Nicolas, G.; Lequeux, N.; Boch, P.; Prene, S.

2001-01-01

The following topics were dealt with: radioactive waste storage, cement materials reacting with radioactive cesium and iodine, chemical barrier formation against radioactive pollution, ceramization, long term stability, XRD, PIXE analysis

Study on flow characteristics of chemically reacting liquid jet

International Nuclear Information System (INIS)

Hong Seon Dae; Okamoto, Koji; Takata, Takashi; Yamaguchi, Akira

2004-07-01

Tube rupture accidents in steam generators of sodium-cooled fast breeder reactors are important for safety because the rupture may propagates to neighboring tubes due to sodium-water reaction. In order to clarify the thermal-hydraulic phenomena in the accidents, the flow pattern and the interface in multi-phase flow must be investigated. The JNC cooperative research scheme on the nuclear fuel cycle with the University of Tokyo has been carried to develop a simultaneous measurement system of concentration and velocity profiles and to evaluate influence of chemical reaction on mixing phenomena. In the experiments, aqueous liquor of acetic acid and ammonium hydroxide are selected as a simulant fluid instead of liquid sodium and water vapor. The following conclusions are obtained in this research. Laser Induced Fluorescence (LIF) technique was adopted to measure reacting zone and pH distribution in chemically reacting liquid round free jet. As a result, it was found that the chemical reaction, which took place at the interface between the jet and outer flow, suppressed the mixing phenomenon (in 2001 research). Dynamic Particle Image Velocimetry (PIV) method was developed to measure instantaneous velocity profile with high temporal resolution. In the Dynamic PIV, a high-speed video camera coupled with a high-speed laser pulse generator was implemented. A time-line trend of interfacial area in the free jet was investigated with the Dynamic PIV. This technique was also applied to a complicated geometry (in 2002 research). A new algorithms for image analysis was developed to evaluated the Dynamic PIV data in detail. The characteristics of the mixing phenomenon with reacting jet such as the turbulent kinetic energy and the Reynolds stress were estimated in a spatial and temporal spectrum (in 2003 research). (author)

Direct numerical simulation of turbulent, chemically reacting flows

Science.gov (United States)

Doom, Jeffrey Joseph

This dissertation: (i) develops a novel numerical method for DNS/LES of compressible, turbulent reacting flows, (ii) performs several validation simulations, (iii) studies auto-ignition of a hydrogen vortex ring in air and (iv) studies a hydrogen/air turbulent diffusion flame. The numerical method is spatially non-dissipative, implicit and applicable over a range of Mach numbers. The compressible Navier-Stokes equations are rescaled so that the zero Mach number equations are discretely recovered in the limit of zero Mach number. The dependent variables are co--located in space, and thermodynamic variables are staggered from velocity in time. The algorithm discretely conserves kinetic energy in the incompressible, inviscid, non--reacting limit. The chemical source terms are implicit in time to allow for stiff chemical mechanisms. The algorithm is readily applicable to complex chemical mechanisms. Good results are obtained for validation simulations. The algorithm is used to study auto-ignition in laminar vortex rings. A nine species, nineteen reaction mechanism for H2/air combustion proposed by Mueller et al. [37] is used. Diluted H 2 at ambient temperature (300 K) is injected into hot air. The simulations study the effect of fuel/air ratio, oxidizer temperature, Lewis number and stroke ratio (ratio of piston stroke length to diameter). Results show that auto--ignition occurs in fuel lean, high temperature regions with low scalar dissipation at a 'most reactive' mixture fraction, zeta MR (Mastorakos et al. [32]). Subsequent evolution of the flame is not predicted by zetaMR; a most reactive temperature TMR is defined and shown to predict both the initial auto-ignition as well as subsequent evolution. For stroke ratios less than the formation number, ignition in general occurs behind the vortex ring and propagates into the core. At higher oxidizer temperatures, ignition is almost instantaneous and occurs along the entire interface between fuel and oxidizer. For stroke

Does the StartReact Effect Apply to First-Trial Reactive Movements?

Directory of Open Access Journals (Sweden)

Katrin Sutter

Full Text Available StartReact is the acceleration of reaction time by a startling acoustic stimulus (SAS. The SAS is thought to release a pre-prepared motor program. Here, we investigated whether the StartReact effect is applicable to the very first trial in a series of repeated unpractised single-joint movements.Twenty healthy young subjects were instructed to perform a rapid ankle dorsiflexion movement in response to an imperative stimulus. Participants were divided in two groups of ten. Both groups performed 17 trials. In one group a SAS (116 dB was given in the first trial, whereas the other group received a non-startling sound (70 dB as the first imperative stimulus. In the remaining 16 trials, the SAS was given as the imperative stimulus in 25% of the trials in both groups. The same measurement was repeated one week later, but with the first-trial stimuli counterbalanced between groups.When a SAS was given in the very first trial, participants had significantly shorter onset latencies compared to first-trial responses to a non-startling stimulus. Succeeding trials were significantly faster compared to the first trial, both for trials with and without a SAS. However, the difference between the first and succeeding trials was significantly larger for responses to a non-startling stimulus compared to responses triggered by a SAS. SAS-induced acceleration in the first trial of the second session was similar to that in succeeding trials of session 1.The present results confirm that the StartReact phenomenon also applies to movements that have not yet been practiced in the experimental context. The excessive SAS-induced acceleration in the very first trial may be due to the absence of integration of novel context-specific information with the existing motor memory for movement execution. Our findings demonstrate that StartReact enables a rapid release of motor programs in the very first trial also without previous practice, which might provide a behavioural

Direct numerical simulation of turbulent reacting flows

Energy Technology Data Exchange (ETDEWEB)

Chen, J.H. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01

The development of turbulent combustion models that reflect some of the most important characteristics of turbulent reacting flows requires knowledge about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between the turbulence and the chemistry is so strong in certain regimes that is is very difficult to isolate the role played by one individual phenomenon. Direct numerical simulation (DNS) is an extremely useful tool to study in detail the turbulence-chemistry interactions in certain well defined regimes. Globally, non-premixed flames are controlled by two limiting cases: the fast chemistry limit, where the turbulent fluctuations. In between these two limits, finite-rate chemical effects are important and the turbulence interacts strongly with the chemical processes. This regime is important because industrial burners operate in regimes in which, locally the flame undergoes extinction, or is at least in some nonequilibrium condition. Furthermore, these nonequilibrium conditions strongly influence the production of pollutants. To quantify the finite-rate chemistry effect, direct numerical simulations are performed to study the interaction between an initially laminar non-premixed flame and a three-dimensional field of homogeneous isotropic decaying turbulence. Emphasis is placed on the dynamics of extinction and on transient effects on the fine scale mixing process. Differential molecular diffusion among species is also examined with this approach, both for nonreacting and reacting situations. To address the problem of large-scale mixing and to examine the effects of mean shear, efforts are underway to perform large eddy simulations of round three-dimensional jets.

Low Mach number asymptotics for reacting compressible fluid flows

Czech Academy of Sciences Publication Activity Database

Feireisl, Eduard; Petzeltová, Hana

2010-01-01

Roč. 26, č. 2 (2010), s. 455-480 ISSN 1078-0947 R&D Projects: GA ČR GA201/05/0164 Institutional research plan: CEZ:AV0Z10190503 Keywords : low Mach number * Navier-Stokes-Fourier system * reacting fluids Subject RIV: BA - General Mathematics Impact factor: 0.986, year: 2010 http://www.aimsciences.org/journals/displayArticles.jsp?paperID=4660

Wireless sensing system for non-invasive monitoring of attributes of contents in a container

Science.gov (United States)

Woodard, Stanley E. (Inventor)

2010-01-01

A wireless sensing system monitors the level, temperature, magnetic permeability and electrical dielectric constant of a non-gaseous material in a container. An open-circuit electrical conductor is shaped to form a two-dimensional geometric pattern that can store and transfer electrical and magnetic energy. The conductor resonates in the presence of a time-varying magnetic field to generate a harmonic response. The conductor is mounted in an environmentally-sealed housing. A magnetic field response recorder wirelessly transmits the time-varying magnetic field to power the conductor, and wirelessly detects the harmonic response that is an indication of at least one of level of the material in the container, temperature of the material in the container, magnetic permeability of the material in the container, and dielectric constant of the material in the container.

Molecular Simulation of Reacting Systems; TOPICAL

International Nuclear Information System (INIS)

THOMPSON, AIDAN P.

2002-01-01

The final report for a Laboratory Directed Research and Development project entitled, Molecular Simulation of Reacting Systems is presented. It describes efforts to incorporate chemical reaction events into the LAMMPS massively parallel molecular dynamics code. This was accomplished using a scheme in which several classes of reactions are allowed to occur in a probabilistic fashion at specified times during the MD simulation. Three classes of reaction were implemented: addition, chain transfer and scission. A fully parallel implementation was achieved using a checkerboarding scheme, which avoids conflicts due to reactions occurring on neighboring processors. The observed chemical evolution is independent of the number of processors used. The code was applied to two test applications: irreversible linear polymerization and thermal degradation chemistry

Characterization of the Material Microstructure for Reactive Material Design. 3rd Quarterly Progress Report II/2008

Science.gov (United States)

2008-08-05

metallic) materials, which fragment under certain dynamic loading conditions into small particles, which can chemically react with a suitable ambient ...medium, such as shock heated ambient air or hot detonation products. Such materials could be effectively used to devise new or improved weapons with...test is blue. The impacto conditions of the the center of the the opposite surfa reflection of the w Figure 6.1: Example o specimen. Another aspect

Fusion Reactor Materials

International Nuclear Information System (INIS)

Moons, F.

1998-01-01

SCK-CEN's programme on fusion reactor materials includes studies (1) to investigate fracture mechanics of neutron-irradiated beryllium; (2) to describe the helium behaviour in irradiated beryllium at atomic scale; (3) to define the kinetics of beryllium reacting with air or steam; (3) to perform a feasibility study for the testing of integrated blanket modules under neutron irradiation. Progress and achievements in 1997 are reported

Rule-Based Multidisciplinary Tool for Unsteady Reacting Real-Fluid Flows, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — A design and analysis computational tool is proposed for simulating unsteady reacting flows in combustor devices used in reusable launch vehicles. Key aspects...

Impact of small variations in LDR for late-reacting tissue in gyn brachytherapy

International Nuclear Information System (INIS)

Bourel, Victor J.; Torre, Marcela de la; Rodriguez, Isabel

1996-01-01

Introduction: The linear-quadratic model shows that while a slight variation in the LDR Brachytherapy dose rate affects just a little the tumoral tissue ERD (Extrapolated Response Dose), the effect can be very strong in the late reacting tissues. The LDR Brachytherapy in cervix cancer is done with a dose rate in point A that range between 0.5 Gy/h and 0.7 Gy/h. This small range is a very heavy variable to find equivalent schemes. Material and Methods: Whith the LC10 program (based in the linear-quadratic model developed in our centre) a radiobiological analysis of the GYN Brachytherapy considering the dosimetric distribution of the most usual applicators is done. Different studies show that the critical rectal and bladder point doses in reference to point A ranges between 60% and 80%. Bearing this in mind, and the typical variables (tissue parameters, number of fractions, dose per fraction, total dose, etc.) the effect of the LDR dose rate variation in particularly analysed while calculating the equivalent HDR scheme. Result and discussion: When equivalent schemes are calculated in practise it is found that the HDR number of fractions depends highly on the LDR dose rate, that's why for one specific LDR scheme is necessary even to duplicate the HDR number of fractions to find the unique equivalent scheme when varying the dose rate from 0.5 Gy/h to 0.7 Gy/h. This also shows that the same LDR scheme using 0.5 Gy/h or 0.7 Gy/h is radiobiologically different (up to 20% in the late reacting tissue ERD). Conclusion: It is very important to report with great detail the LDR dose rate with which the gynaecological treatments have been performed because this variable is decisive to compare the results with other LDR or HDR schemes

Numerical simulation of low Mach number reacting flows

International Nuclear Information System (INIS)

Bell, J B; Aspden, A J; Day, M S; Lijewski, M J

2007-01-01

Using examples from active research areas in combustion and astrophysics, we demonstrate a computationally efficient numerical approach for simulating multiscale low Mach number reacting flows. The method enables simulations that incorporate an unprecedented range of temporal and spatial scales, while at the same time, allows an extremely high degree of reaction fidelity. Sample applications demonstrate the efficiency of the approach with respect to a traditional time-explicit integration method, and the utility of the methodology for studying the interaction of turbulence with terrestrial and astrophysical flame structures

REAC/TS Radiation Accident Registry: An Overview

Energy Technology Data Exchange (ETDEWEB)

Doran M. Christensen, DO, REAC/TS Associate Director and Staff Physician Becky Murdock, REAC/TS Registry and Health Physics Technician

2012-12-12

Over the past four years, REAC/TS has presented a number of case reports from its Radiation Accident Registry. Victims of radiological or nuclear incidents must meet certain dose criteria for an incident to be categorized as an “accident” and be included in the registry. Although the greatest numbers of “accidents” in the United States that have been entered into the registry involve radiation devices, the greater percentage of serious accidents have involved sealed sources of one kind or another. But if one looks at the kinds of accident scenarios that have resulted in extreme consequence, i.e., death, the greater share of deaths has occurred in medical settings.

Quantitative imaging of turbulent and reacting flows

Energy Technology Data Exchange (ETDEWEB)

Paul, P.H. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01

Quantitative digital imaging, using planar laser light scattering techniques is being developed for the analysis of turbulent and reacting flows. Quantitative image data, implying both a direct relation to flowfield variables as well as sufficient signal and spatial dynamic range, can be readily processed to yield two-dimensional distributions of flowfield scalars and in turn two-dimensional images of gradients and turbulence scales. Much of the development of imaging techniques to date has concentrated on understanding the requisite molecular spectroscopy and collision dynamics to be able to determine how flowfield variable information is encoded into the measured signal. From this standpoint the image is seen as a collection of single point measurements. The present effort aims at realizing necessary improvements in signal and spatial dynamic range, signal-to-noise ratio and spatial resolution in the imaging system as well as developing excitation/detection strategies which provide for a quantitative measure of particular flowfield scalars. The standard camera used for the study is an intensified CCD array operated in a conventional video format. The design of the system was based on detailed modeling of signal and image transfer properties of fast UV imaging lenses, image intensifiers and CCD detector arrays. While this system is suitable for direct scalar imaging, derived quantities (e.g. temperature or velocity images) require an exceptionally wide dynamic range imaging detector. To apply these diagnostics to reacting flows also requires a very fast shuttered camera. The authors have developed and successfully tested a new type of gated low-light level detector. This system relies on fast switching of proximity focused image-diode which is direct fiber-optic coupled to a cooled CCD array. Tests on this new detector show significant improvements in detection limit, dynamic range and spatial resolution as compared to microchannel plate intensified arrays.

Unique reduced graphene oxide as efficient anode material in Li ion ...

Indian Academy of Sciences (India)

2018-03-29

Mar 29, 2018 ... as an electrode material in dye-sensitized solar cell [1], super- capacitor [2] and Li ion battery ... Ar-filled glove box. In each of the coin cell, ... Li reacts with suitable materials' defects at low potential and as they charge, bonds ...

Prevalence of Allergy to Natural Rubber Latex and Potential Cross Reacting Food in Operation Room Staff in Shiraz Hospitals -2006

Directory of Open Access Journals (Sweden)

H Nabavizade

2007-07-01

Full Text Available Introduction & Objective: Allergic reactions to natural rubber latex have increased during past 10 years especially among health care workers and patients with high exposure to latex allergens. Allergic reaction to latex is related to many diseases like occupational asthma. This study was performed to determine the prevalence of allergy to natural rubber latex and potential cross reacting food in operation room staff in Shiraz hospitals. Materials & Methods: In this cross-sectional descriptive study five hundred eighty operation room staff of ten private and state hospitals in Shiraz completed latex allergy questionnaire. They were questioned about personal history and previous history of latex sensitivity, symptoms of latex reactivity and about other allergies particularly to foods that may cross react with latex. Informed consent was obtained and skin prick testing was performed with natural rubber latex. Skin prick tests were done with three potentially cross reacting food (banana, Kiwi, and potato. The obtained data were analyzed with SPSS software and Chi-square test. Results: Among the 580 operation room workers 104 (17.9 % of participants were positive to latex skin test. We found a significant association between positive skin test to latex in operation room staff and atopy, urticaria and food allergy. Positive skin test to latex related to positive kiwi skin test (p<0.05. The prevalence did not vary by sex, age, education, surgical and non surgical glove users, history of contact dermatitis or smoking status. Conclusion: Latex allergy has a high prevalence in personnel of operation room. Evaluation of present symptom and prediction of future disease necessitate screening test in individuals at risk.

Effects of continuum breakdown on hypersonic aerothermodynamics for reacting flow

Science.gov (United States)

Holman, Timothy D.; Boyd, Iain D.

2011-02-01

This study investigates the effects of continuum breakdown on the surface aerothermodynamic properties (pressure, stress, and heat transfer rate) of a sphere in a Mach 25 flow of reacting air in regimes varying from continuum to a rarefied gas. Results are generated using both continuum [computational fluid dynamics (CFD)] and particle [direct simulation Monte Carlo (DSMC)] approaches. The DSMC method utilizes a chemistry model that calculates the backward rates from an equilibrium constant. A preferential dissociation model is modified in the CFD method to better compare with the vibrationally favored dissociation model that is utilized in the DSMC method. Tests of these models are performed to confirm their validity and to compare the chemistry models in both numerical methods. This study examines the effect of reacting air flow on continuum breakdown and the surface properties of the sphere. As the global Knudsen number increases, the amount of continuum breakdown in the flow and on the surface increases. This increase in continuum breakdown significantly affects the surface properties, causing an increase in the differences between CFD and DSMC. Explanations are provided for the trends observed.

Multiphase reacting flows modelling and simulation

CERN Document Server

Marchisio, Daniele L

2007-01-01

The papers in this book describe the most widely applicable modeling approaches and are organized in six groups covering from fundamentals to relevant applications. In the first part, some fundamentals of multiphase turbulent reacting flows are covered. In particular the introduction focuses on basic notions of turbulence theory in single-phase and multi-phase systems as well as on the interaction between turbulence and chemistry. In the second part, models for the physical and chemical processes involved are discussed. Among other things, particular emphasis is given to turbulence modeling strategies for multiphase flows based on the kinetic theory for granular flows. Next, the different numerical methods based on Lagrangian and/or Eulerian schemes are presented. In particular the most popular numerical approaches of computational fluid dynamics codes are described (i.e., Direct Numerical Simulation, Large Eddy Simulation, and Reynolds-Averaged Navier-Stokes approach). The book will cover particle-based meth...

Non-equilibrium reacting gas flows kinetic theory of transport and relaxation processes

CERN Document Server

Nagnibeda, Ekaterina; Nagnibeda, Ekaterina

2009-01-01

This volume develops the kinetic theory of transport phenomena and relaxation processes in the flows of reacting gas mixtures. The theory is applied to the modeling of non-equilibrium flows behind strong shock waves, in the boundary layer, and in nozzles.

'REACTS'. A pragmatic approach for providing medical care and physician education for radiation emergencies

International Nuclear Information System (INIS)

Lushbaugh, C.C.; Andrews, G.A.; Huebner, K.F.; Cloutier, R.J.; Beck, W.L.; Berger, J.D.

1976-01-01

Because serious radiation incidents have been rare, few medical personnel (notably only some in France, Russia, Belgium, Canada, Yugoslavia, Japan, Great Britain and the United States) have first-hand experience in radiation-accident management. The generation of physicians who participated in those accidents now needs to pass on the bits of knowledge that were gleaned from them. These case histories are difficult for the local, non-radiology physician to obtain when he is called upon to help formulate the medical-emergency response plan required everywhere for licensing power reactors. The Radiation Emergency Assistance Center and Training Site (REACTS) in Oak Ridge, Tennessee, supported by the US Energy Research and Development Administration, is designed to meet these medical and educational needs. REACTS, located in the Oak Ridge Hospital of the Methodist Church, is not involved in the hospital's daily community functions except insofar as REACTS is the radiation emergency arm of the area's major disaster plan. Its dual mission is training physicians, nurses, and paramedical emergency personnel in radiation-accident management, and treating irradiated and contaminated persons. Its training activities are carried out by the Special Training Division of Oak Ridge Associated Universities. Formal courses in radiation medicine and health physics and practical laboratory experience are now conducted twice a year for physicians. They will be expanded in the future to include training of paramedical personnel. Follow-up studies of radiation-accident survivors are carried out in REACTS to ensure the preservation of valuable human data and radiation-accident experiences. This unique facility and its staff are dedicated to meet the needs of the far-flung public and private medical domains in the United States for nuclear-production energy

Tax havens under international pressure: How do they react?

OpenAIRE

Patrice Pieretti; Giuseppe Pulina

2015-01-01

This paper contributes to the literature about tax havens by providing a more comprehensive analysis of their role. The aim is to analyze how low-tax jurisdictions can react to growing international pressure exerted, by high-tax countries, to enforce compliance with anti aggressive tax planning standards. To this end, we model how a small tax haven tries to be attractive to multinationals located in a high-tax region by providing aggressive tax planning services and/or a favorable environment...

Responding to excessive alcohol consumption in third-level (REACT): a study protocol.

Science.gov (United States)

Davoren, Martin P; Calnan, Susan; Mulcahy, Judith; Lynch, Emily; Perry, Ivan J; Byrne, Michael

2018-05-11

Problem alcohol use is an ongoing, worldwide phenomenon of considerable concern. Throughout the past 20 years, national policies have noted the importance of students when tackling alcohol consumption. Considering alcohol is a multifaceted issue, a multi-component response is required to combat its excessive use. This protocol sets out the approach used for developing, implementing and evaluating the REACT (Responding to Excessive Alcohol Consumption in Third-level) Programme. This evaluation will provide the evidence base for programme development, implementation and improvement. Stage one involved defining the multi-component intervention. This was developed following a systematic review of existing literature and a Delphi-consensus workshop involving university students, staff and relevant stakeholders. Following this, the programme is being implemented across the Higher Education sector in Ireland. A number of Higher Education Institutes have declined the invitation to participate in the programme. These institutions will act as control sites. Each intervention site will have a steering committee whose membership will include a mix of students and academic and student service staff. This steering committee will report to the REACT research team on the implementation of mandatory and optional action points at local sites. An online cross-sectional study at baseline and two-years post intervention will be utilised to determine the impact of the REACT programme. The impact assessment will focus on (1) whether the intervention has reduced alcohol consumption among third-level students (2); whether the programme altered students attitudes toward alcohol and (3) whether the programme has decreased the second-hand effects associated with excessive consumption. Finally, qualitative research will focus on factors influencing the take-up and implementation of this programme as well as students' views on the initiative. Alcohol consumption has remained on the policy

THE STABILITY OF OPTICALLY THIN REACTING PLASMAS: EFFECTS OF THE BULK VISCOSITY

International Nuclear Information System (INIS)

Ibanez S, Miguel H.

2009-01-01

The thermochemical stability of reacting plasmas is analyzed by taking into account the change in the thermodynamical equilibrium values during the fluctuation. This shift in the equilibrium produces two main effects: a change in the four instability criteria for reacting gases resulting when the above effect is neglected and adds a fifth instability criterion due to the fact that the corresponding secular equation becomes a fifth-order polynomial. The above results are applied to several plasma models, in particular, to a photoionized hydrogen plasma for which the bulk viscosity can be more important than the dynamic viscosity and the thermometric conductivity. Therefore, the bulk viscosity may quench thermochemical instabilities were the thermal conduction is unable of stabilizing. This occurs for low values of the photoionizing energy E. The implications of the above results in explaining the formation of clump structures in different regions of the interstellar medium are outlined.

Effect of lunar materials on plant tissue culture.

Science.gov (United States)

Walkinshaw, C. H.; Venketeswaran, S.; Baur, P. S.; Croley, T. E.; Scholes, V. E.; Weete, J. D.; Halliwell, R. S.; Hall, R. H.

1973-01-01

Lunar material collected during the Apollo 11, 12, 14, and 15 missions has been used to treat 12 species of higher plant tissue cultures. Biochemical and morphological studies have been conducted on several of these species. Tobacco tissue cultures treated with 0.22 g of lunar material exhibited increased greening more complex chloroplasts, less cytoplasmic vacuolation and greater vesiculation. Pine tissue cultures reacted to treatment by an increased deposition of tannin-like materials. The percentage of dry weight and soluble protein was increased in cultures treated with either lunar or terrestrial rock materials.

Coating materials

International Nuclear Information System (INIS)

Ozeki, Takao; Kimura, Tadashi; Kobayashi, Juichi; Maeda, Yutaka; Nakamoto, Hideo.

1969-01-01

A non-solvent type coating material composition having properties as good as thermosetting acrylic or amino alkid resins is provided by employing active energy irradiation, particularly electron beams, using a radically polymerizable low molecular compound (A) (hereafter called an oligomer) containing at least two vinyl radicals in one molecule. This oligomer is produced by reacting an epoxy-containing vinyl monomer with alpha-, beta-ethylene unsaturated carboxylic acids or their anhydrides. The composition (I) contains 10% - 100% of this oligomer. In embodiments, an oligomer having a fiberous trivinyl construction is produced by reacting 180 parts by weight of glycidyl methacrylate ester with 130 parts of itaconic acid in the presence of a polymerization-inhibitor and an addition reaction catalyst at 90 0 C for 6 hours. In practice, the coating material compositions (1), consist of the whole oligomer [I-1]; (2), consist of 10-90% of (A) component and 90%-10% of vinyl monomers containing at least 30% (meth) acrylic monomer [I-2]; (3), 10%-90% of component (A) and 90%-10% of other monomers containing at least two vinyl radicals [I-3]; (4), a mixture of (I-2) and (I-3), [I-4]; and (5), consist of 50% or less unsaturated polyester of 500-5,000 molecular weight range or drying oil, or alkyd resin of 500-5,000 molecular weight range modified by drying oil, [I-5]. As a catalyst a tertiary amino vinyl compound is preferred. Five examples are given. (Iwakiri, K.)

Thermal properties of wood reacted with a phosphorus pentoxide–amine system

Science.gov (United States)

Hong-Lin Lee; George C. Chen; Roger M. Rowell

2004-01-01

The objective of this research was to improve the fire-retardant properties of wood in one treatment using a phosphorus pentoxide–amine system. Phosphorus pentoxide and 16 amines including alkyl, halophenyl, and phenyl amines were compounded in N,N-dimethylformamide and the resulting solutions containing phosphoramides were reacted with wood. The characteristics of...

A three-dimensional fully coupled thermo-mechanical model for Self-reacting Friction Stir Welding of Aluminium AA6061 sheets

International Nuclear Information System (INIS)

Singh, Piyush; Biswas, Pankaj; Kore, Sachin D.

2016-01-01

In the present work a three dimensional model of self-reacting friction stir welding in aluminium alloy AA6061 has been developed based on the Computational Fluid Dynamics (CFD) approach using COMSOL Multiphysics software. The temperature dependent material properties have been incorporated in the model from available literature. A slip-stick contact between the workpiece and tool surface has been considered with the slip factor varying linearly with distance. The methodology adopted has been validated with experimental results available in the literature. The temperature distribution observed has been found to be asymmetric about the weld centre line. The maximum temperature has been observed on the advancing side of the weld. However, the temperature distribution across the thickness has been found to be almost symmetric about the mid thickness plane. An hourglass shaped temperature distribution has been observed across the cross-section of the weld. The material flow velocity distribution shows that the deformation zone is limited to a very small region around the tool. (paper)

ReACT Methodology Proof of Concept Final Report

Energy Technology Data Exchange (ETDEWEB)

Bri Rolston; Sarah Freeman

2014-03-01

The Department of Energy’s Office of Electricity Delivery and Energy Reliability (DOE-OE) funded INL Researchers to evaluate a novel process for assessing and mitigating cyber security risks. The proof of concept level of the method was tested in an industry environment. This case study, plus additional case studies will support the further development of the method into a tool to assist industry in securing their critical networks. This report provides an understanding of the process developed in the Response Analysis and Characterization Tool (ReACT) project. This report concludes with lessons learned and a roadmap for final development of these tools for use by industry.

Heat and mass transfer for turbulent flow of chemically reacting gas in eccentric annular channels

International Nuclear Information System (INIS)

Besedina, T.V.; Tverkovkin, B.E.; Udot, A.V.; Yakushev, A.P.

1988-01-01

Because of the possibility of using dissociating gases as coolants and working bodies of nuclear power plants, it is necessary to develop computational algorithms for calculating heat and mass transfer processes under conditions of nonequilibrium flow of chemically reacting gases not only in axisymmetric channels, but also in channels with a complex transverse cross section (including also in eccentric annular channels). An algorithm is proposed for calculating the velocity, temperature, and concentration fields under conditions of cooling of a cylindrical heat-releasing rod, placed off-center in a circular casing pipe, by a longitudinal flow of chemically reacting gas [N 2 O 4

Cristallini Material Review and Selection

Energy Technology Data Exchange (ETDEWEB)

Smith, Nicholas [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Savina, Joseph [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hebden, Andrew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

2016-09-30

The creation of a handheld unit to utilize the Cristallini method of uranium hexafluoride sampling requires the identification and qualification of suitable substrate materials. These materials will need to quickly and completely react with the process gas, resist vapor locking under vacuum, while being relatively inexpensive and homogeneous. Two forms of powdered alumina have been chosen for a head-to-head comparison during upcoming uranium hexafluoride tests. Both materials have shown ideal uptake characteristics during tungsten hexafluoride tests with a high loading capacity and no measureable breakthrough. They have also been shown to work well at vacuums below 10 Torr, are commercially available and inexpensive. In addition, two possible hydrogen fluoride trapping materials, sodium fluoride and saturated calcium carbonate, have been identified for further testing.

Stable isotope enrichment: Current and future potential

International Nuclear Information System (INIS)

Tracy, J.G.; Aaron, W.S.

1992-01-01

Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities

Stable isotope enrichment - current and future potential

International Nuclear Information System (INIS)

Tracy, J.G.; Aaron, W.S.

1993-01-01

Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL. This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities. (orig.)

IgE antibodies of fish allergic patients cross-react with frog parvalbumin.

Science.gov (United States)

Hilger, C; Thill, L; Grigioni, F; Lehners, C; Falagiani, P; Ferrara, A; Romano, C; Stevens, W; Hentges, F

2004-06-01

The major allergens in fish are parvalbumins. Important immunoglobulin (Ig)E cross-recognition of parvalbumins from different fish species has been shown. Recently frog parvalbumin alpha has been found to be responsible for a case of IgE-mediated anaphylaxis triggered by the ingestion of frog meat. The aim of this study was to investigate whether IgE antibodies of fish allergic persons cross-react with frog parvalbumin and to appreciate its clinical relevance. The sera of 15 fish allergic patients and one fish and frog allergic patient were tested by IgE-immunoblotting against frog muscle extract. Sera were tested against recombinant parvalbumin alpha and beta from Rana esculenta. Skin prick tests were performed in selected patients with recombinant frog parvalbumin. Ca(2+) depletion experiments and inhibition studies with purified cod and frog recombinant parvalbumin were done to characterize the cross-reactive pattern. Fourteen of the sera tested had IgE antibodies recognizing low molecular weight components in frog muscle extract. Calcium depletion experiments or inhibition of patient sera with purified cod parvalbumin led to a significant or complete decrease in IgE binding. When tested against recombinant parvalbumins, three of 13 sera reacted with alpha parvalbumin and 11 of 12 reacted with beta parvalbumin from R. esculenta. Skin prick tests performed with recombinant frog parvalbumin were positive in fish allergic patients. Inhibition studies showed that a fish and frog allergic patient was primarily sensitized to fish parvalbumin. Cod parvalbumin, a major cross-reactive allergen among different fish species, shares IgE binding epitopes with frog parvalbumin. This in vitro cross-reactivity seems to be also clinically relevant. Parvalbumins probably represent a new family of cross-reactive allergens.

Characterization of pollucite as a material for the long term storage of cesium-137

International Nuclear Information System (INIS)

Strachan, D.M.; Schulz, W.W.

1977-06-01

Storage of nuclear waste requires materials which are thermodynamically stable. Pollucite (Cs 2 O . Al 2 O 3 . 4SiO 2 ) may be an acceptable material for the long-term storage of the purified 137 CsCl. Pollucite is made at near theoretical yields when CsCl (or any cesium salt) reacts at about 970 0 K with a montmorillonite-containing clay. Pollucite dissolves in deionized water at rates which are less than 2 x 10 -9 kg/(m 2 . s) based on cesium. Microstructural analyses show that cesium reacts with the montmorillonite clay to form ill-defined pollucite crystals which contain low concentrations of the impurities found in the clay. Although further work needs to be done, pollucite is considered to be an excellent material for the long-term storage of 137 Cs

Development of a Reduced-Order Model for Reacting Gas-Solids Flow using Proper Orthogonal Decomposition

Energy Technology Data Exchange (ETDEWEB)

McDaniel, Dwayne [Florida International Univ., Miami, FL (United States); Dulikravich, George [Florida International Univ., Miami, FL (United States); Cizmas, Paul [Florida International Univ., Miami, FL (United States)

2017-11-27

This report summarizes the objectives, tasks and accomplishments made during the three year duration of this research project. The report presents the results obtained by applying advanced computational techniques to develop reduced-order models (ROMs) in the case of reacting multiphase flows based on high fidelity numerical simulation of gas-solids flow structures in risers and vertical columns obtained by the Multiphase Flow with Interphase eXchanges (MFIX) software. The research includes a numerical investigation of reacting and non-reacting gas-solids flow systems and computational analysis that will involve model development to accelerate the scale-up process for the design of fluidization systems by providing accurate solutions that match the full-scale models. The computational work contributes to the development of a methodology for obtaining ROMs that is applicable to the system of gas-solid flows. Finally, the validity of the developed ROMs is evaluated by comparing the results against those obtained using the MFIX code. Additionally, the robustness of existing POD-based ROMs for multiphase flows is improved by avoiding non-physical solutions of the gas void fraction and ensuring that the reduced kinetics models used for reactive flows in fluidized beds are thermodynamically consistent.

MHD flow and heat transfer of a viscous reacting fluid over a ...

African Journals Online (AJOL)

This paper presents a boundary layer flow analysis for a viscous, incompressible, electrically conducting reacting fluid over a stretching sheet in the presence of a magnetic field. It is shown that the Hartmann, Prandtl and the Eckert numbers have effect on the velocity and temperature fields. Journal of the Nigerian ...

Propel: A Discontinuous-Galerkin Finite Element Code for Solving the Reacting Navier-Stokes Equations

Science.gov (United States)

Johnson, Ryan; Kercher, Andrew; Schwer, Douglas; Corrigan, Andrew; Kailasanath, Kazhikathra

2017-11-01

This presentation focuses on the development of a Discontinuous Galerkin (DG) method for application to chemically reacting flows. The in-house code, called Propel, was developed by the Laboratory of Computational Physics and Fluid Dynamics at the Naval Research Laboratory. It was designed specifically for developing advanced multi-dimensional algorithms to run efficiently on new and innovative architectures such as GPUs. For these results, Propel solves for convection and diffusion simultaneously with detailed transport and thermodynamics. Chemistry is currently solved in a time-split approach using Strang-splitting with finite element DG time integration of chemical source terms. Results presented here show canonical unsteady reacting flow cases, such as co-flow and splitter plate, and we report performance for higher order DG on CPU and GPUs.

Why Targets of Economic Sanctions React Differently: Reference Point Effects on North Korea and Libya

Directory of Open Access Journals (Sweden)

Jiyoun Park

2017-06-01

Full Text Available The international community has frequently introduced economic sanctions to curb the proliferation of weapons of mass destruction, to which each target nation has reacted differently. This paper explores the reasons why each target of economic sanctions reacts differently by specif- ically building a model based on reference point effects, and by analyzing the cases of North Korea and Libya. According to the results, when the reference point level increases, as in the case of North Korea, the target resists more firmly; on the other hand, when the reference point decreases, like in the case of Libya, the target resists more subtly.

The Responsive Environmental Assessment for Classroom Teaching (REACT): the dimensionality of student perceptions of the instructional environment.

Science.gov (United States)

Nelson, Peter M; Demers, Joseph A; Christ, Theodore J

2014-06-01

This study details the initial development of the Responsive Environmental Assessment for Classroom Teachers (REACT). REACT was developed as a questionnaire to evaluate student perceptions of the classroom teaching environment. Researchers engaged in an iterative process to develop, field test, and analyze student responses on 100 rating-scale items. Participants included 1,465 middle school students across 48 classrooms in the Midwest. Item analysis, including exploratory and confirmatory factor analysis, was used to refine a 27-item scale with a second-order factor structure. Results support the interpretation of a single general dimension of the Classroom Teaching Environment with 6 subscale dimensions: Positive Reinforcement, Instructional Presentation, Goal Setting, Differentiated Instruction, Formative Feedback, and Instructional Enjoyment. Applications of REACT in research and practice are discussed along with implications for future research and the development of classroom environment measures. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Sticky tunes: how do people react to involuntary musical imagery?

Directory of Open Access Journals (Sweden)

Victoria J Williamson

Full Text Available The vast majority of people experience involuntary musical imagery (INMI or 'earworms'; perceptions of spontaneous, repetitive musical sound in the absence of an external source. The majority of INMI episodes are not bothersome, while some cause disruption ranging from distraction to anxiety and distress. To date, little is known about how the majority of people react to INMI, in particular whether evaluation of the experience impacts on chosen response behaviours or if attempts at controlling INMI are successful or not. The present study classified 1046 reports of how people react to INMI episodes. Two laboratories in Finland and the UK conducted an identical qualitative analysis protocol on reports of INMI reactions and derived visual descriptive models of the outcomes using grounded theory techniques. Combined analysis carried out across the two studies confirmed that many INMI episodes were considered neutral or pleasant, with passive acceptance and enjoyment being among the most popular response behaviours. A significant number of people, however, reported on attempts to cope with unwanted INMI. The most popular and effective behaviours in response to INMI were seeking out the tune in question, and musical or verbal distraction. The outcomes of this study contribute to our understanding of the aetiology of INMI, in particular within the framework of memory theory, and present testable hypotheses for future research on successful INMI coping strategies.

Sticky Tunes: How Do People React to Involuntary Musical Imagery?

Science.gov (United States)

Williamson, Victoria J.; Liikkanen, Lassi A.; Jakubowski, Kelly; Stewart, Lauren

2014-01-01

The vast majority of people experience involuntary musical imagery (INMI) or ‘earworms’; perceptions of spontaneous, repetitive musical sound in the absence of an external source. The majority of INMI episodes are not bothersome, while some cause disruption ranging from distraction to anxiety and distress. To date, little is known about how the majority of people react to INMI, in particular whether evaluation of the experience impacts on chosen response behaviours or if attempts at controlling INMI are successful or not. The present study classified 1046 reports of how people react to INMI episodes. Two laboratories in Finland and the UK conducted an identical qualitative analysis protocol on reports of INMI reactions and derived visual descriptive models of the outcomes using grounded theory techniques. Combined analysis carried out across the two studies confirmed that many INMI episodes were considered neutral or pleasant, with passive acceptance and enjoyment being among the most popular response behaviours. A significant number of people, however, reported on attempts to cope with unwanted INMI. The most popular and effective behaviours in response to INMI were seeking out the tune in question, and musical or verbal distraction. The outcomes of this study contribute to our understanding of the aetiology of INMI, in particular within the framework of memory theory, and present testable hypotheses for future research on successful INMI coping strategies. PMID:24497938

SQL Triggers Reacting on Time Events: An Extension Proposal

Science.gov (United States)

Behrend, Andreas; Dorau, Christian; Manthey, Rainer

Being able to activate triggers at timepoints reached or after time intervals elapsed has been acknowledged by many authors as a valuable functionality of a DBMS. Recently, the interest in time-based triggers has been renewed in the context of data stream monitoring. However, up till now SQL triggers react to data changes only, even though research proposals and prototypes have been supporting several other event types, in particular time-based ones, since long. We therefore propose a seamless extension of the SQL trigger concept by time-based triggers, focussing on semantic issues arising from such an extension.

Methane reacts with heteropolyacids chemisorbed on silica to produce acetic acid under soft conditions

KAUST Repository

Sun, Miao; Abou-Hamad, Edy; Rossini, Aaron J.; Zhang, Jizhe; Lesage, Anne; Zhu, Haibo; Pelletier, Jeremie; Emsley, Lyndon; Caps, Valerie; Basset, Jean-Marie

2013-01-01

Selective functionalization of methane at moderate temperature is of crucial economic, environmental, and scientific importance. Here, we report that methane reacts with heteropolyacids (HPAs) chemisorbed on silica to produce acetic acid under soft

Recent advances in ultrafast-laser-based spectroscopy and imaging for reacting plasmas and flames

Science.gov (United States)

Patnaik, Anil K.; Adamovich, Igor; Gord, James R.; Roy, Sukesh

2017-10-01

Reacting flows and plasmas are prevalent in a wide array of systems involving defense, commercial, space, energy, medical, and consumer products. Understanding the complex physical and chemical processes involving reacting flows and plasmas requires measurements of key parameters, such as temperature, pressure, electric field, velocity, and number densities of chemical species. Time-resolved measurements of key chemical species and temperature are required to determine kinetics related to the chemical reactions and transient phenomena. Laser-based, noninvasive linear and nonlinear spectroscopic approaches have proved to be very valuable in providing key insights into the physico-chemical processes governing reacting flows and plasmas as well as validating numerical models. The advent of kilohertz rate amplified femtosecond lasers has expanded the multidimensional imaging of key atomic species such as H, O, and N in a significant way, providing unprecedented insight into preferential diffusion and production of these species under chemical reactions or electric-field driven processes. These lasers not only provide 2D imaging of chemical species but have the ability to perform measurements free of various interferences. Moreover, these lasers allow 1D and 2D temperature-field measurements, which were quite unimaginable only a few years ago. The rapid growth of the ultrafast-laser-based spectroscopic measurements has been fueled by the need to achieve the following when measurements are performed in reacting flows and plasmas. They are: (1) interference-free measurements (collision broadening, photolytic dissociation, Stark broadening, etc), (2) time-resolved single-shot measurements at a rate of 1-10 kHz, (3) spatially-resolved measurements, (4) higher dimensionality (line, planar, or volumetric), and (5) simultaneous detection of multiple species. The overarching goal of this article is to review the current state-of-the-art ultrafast-laser-based spectroscopic

Coating material composition

International Nuclear Information System (INIS)

Kimura, Tadashi; Ozeki, Takao; Kobayashi, Juichi; Nakamoto, Hideo; Maeda, Yutaka.

1969-01-01

A coating material composition is provided which can easily be cross-linked by irradiation with active energy, particularly electron beams and ultraviolet light, using a mixture of a prepolymer (a) with an addition reaction product (b). Such compositions have coating properties as good as thermosetting acrylic or amino alkyd resins. The prepolymer (a) is produced by primarily reacting at least 0.1 mol of saturated cyclocarboxylic acid anhydrides and/or alpha-, beta-ethylene unsaturated carboxylic acid anhydrides by addition reaction with one mol of hydroxyl radicals of a basic polymer having a molecular weight of 1,000 to 100,000, the basic polymer being obtained from 1%-40% of a hydroxyl radical containing vinyl monomer and at least 30% of (meth)acrylate monomer. One mol of the sum of hydroxyl radicals and carboxyl radicals of the primary reaction product undergoes a secondary addition reaction with at least 0.1 mol of an epoxy radical-containing vinyl monomer to form the prepolymer(a). The addition reaction product(b) is produced by reacting an epoxy radical-containing vinyl monomer with alpha-, beta-ethylene unsaturated carboxylic acids or their anhydrides. The coating material composition contains a majority of a mixture consisting of 10%-90% of (a) and 90%-10% of (b) above by weight. Four examples of the production of basic polymers, seven examples of the production of prepolymers, seven examples of the production of oligomers, and five examples of applications are given. (Iwakiri, K.)

Experimental investigation of a reacting transverse jet in a high pressure oscillating vitiated crossflow

Science.gov (United States)

Fugger, Christopher A.

Staged combustion is one design approach in a gas turbine engine to reduce pollutant emission levels. In axially staged combustion, portions of the air and fuel are injected downstream of a lean premixed low NOx primary combustion zone. The gas residence time at elevated temperatures is decreased resulting in lower thermal NOx, and the reduced oxygen and high temperature vitiated primary zone flow further help to reduce pollutant emissions and quickly complete combustion. One implementation of axially staged combustion is transverse fuel jet injection. An important consideration for staged combustion systems, though, is how the primary and secondary combustion zones can couple through the acoustic resonances of the chamber. These couplings can lead to additional source terms that pump energy into the resonant acoustic field and help sustain the high-amplitude combustor pressure oscillations. An understanding of these couplings is important so that it may be possible to design a secondary combustion system that provides inherent damping to the combustor system. To systematically characterize the coupling of a reacting jet in unsteady crossflow in detail, the effects of an an unsteady pressure flowfield and an unsteady velocity flowfield are separately investigated. An optically accessible resonant combustion chamber was designed and built as part of this work to generate a standing wave unsteady vitiated crossflow at a chamber pressure of 0.9 MPa. The location of transverse jet injection corresponds to one of two locations, where one location is the pressure node and the other location the pressure anti-node of the resonant chamber acoustic mode. The injection location is optically accessible, and the dynamic interactions between the transverse jet flow and the 1st and 2nd axial combustor modes are measured using 10 kHz OH-PLIF and 2D PIV. This document analyzes five test cases: two non-reacting jets and three reacting jets. All cases correspond to jet injection

LES-ODT Simulations of Turbulent Reacting Shear Layers

Science.gov (United States)

Hoffie, Andreas; Echekki, Tarek

2012-11-01

Large-eddy simulations (LES) combined with the one-dimensional turbulence (ODT) simulations of a spatially developing turbulent reacting shear layer with heat release and high Reynolds numbers were conducted and compared to results from direct numerical simulations (DNS) of the same configuration. The LES-ODT approach is based on LES solutions for momentum on a coarse grid and solutions for momentum and reactive scalars on a fine ODT grid, which is embedded in the LES computational domain. The shear layer is simulated with a single-step, second-order reaction with an Arrhenius reaction rate. The transport equations are solved using a low Mach number approximation. The LES-ODT simulations yield reasonably accurate predictions of turbulence and passive/reactive scalars' statistics compared to DNS results.

Detecting and Reacting to Change: The Effect of Exposure to Narrow Categorizations

Science.gov (United States)

Chakravarti, Amitav; Fang, Christina; Shapira, Zur

2011-01-01

The ability to detect a change, to accurately assess the magnitude of the change, and to react to that change in a commensurate fashion are of critical importance in many decision domains. Thus, it is important to understand the factors that systematically affect people's reactions to change. In this article we document a novel effect: Decision…

Large Eddy Simulation of Spatially Developing Turbulent Reacting Shear Layers with the One-Dimensional Turbulence Model

Science.gov (United States)

Hoffie, Andreas Frank

Large eddy simulation (LES) combined with the one-dimensional turbulence (ODT) model is used to simulate spatially developing turbulent reacting shear layers with high heat release and high Reynolds numbers. The LES-ODT results are compared to results from direct numerical simulations (DNS), for model development and validation purposes. The LES-ODT approach is based on LES solutions for momentum and pressure on a coarse grid and solutions for momentum and reactive scalars on a fine, one-dimensional, but three-dimensionally coupled ODT subgrid, which is embedded into the LES computational domain. Although one-dimensional, all three velocity components are transported along the ODT domain. The low-dimensional spatial and temporal resolution of the subgrid scales describe a new modeling paradigm, referred to as autonomous microstructure evolution (AME) models, which resolve the multiscale nature of turbulence down to the Kolmogorv scales. While this new concept aims to mimic the turbulent cascade and to reduce the number of input parameters, AME enables also regime-independent combustion modeling, capable to simulate multiphysics problems simultaneously. The LES as well as the one-dimensional transport equations are solved using an incompressible, low Mach number approximation, however the effects of heat release are accounted for through variable density computed by the ideal gas equation of state, based on temperature variations. The computations are carried out on a three-dimensional structured mesh, which is stretched in the transverse direction. While the LES momentum equation is integrated with a third-order Runge-Kutta time-integration, the time integration at the ODT level is accomplished with an explicit Forward-Euler method. Spatial finite-difference schemes of third (LES) and first (ODT) order are utilized and a fully consistent fractional-step method at the LES level is used. Turbulence closure at the LES level is achieved by utilizing the Smagorinsky

Applied patent RFID systems for building reacting HEPA air ventilation system in hospital operation rooms.

Science.gov (United States)

Lin, Jesun; Pai, Jar-Yuan; Chen, Chih-Cheng

2012-12-01

RFID technology, an automatic identification and data capture technology to provide identification, tracing, security and so on, was widely applied to healthcare industry in these years. Employing HEPA ventilation system in hospital is a way to ensure healthful indoor air quality to protect patients and healthcare workers against hospital-acquired infections. However, the system consumes lots of electricity which cost a lot. This study aims to apply the RFID technology to offer a unique medical staff and patient identification, and reacting HEPA air ventilation system in order to reduce the cost, save energy and prevent the prevalence of hospital-acquired infection. The system, reacting HEPA air ventilation system, contains RFID tags (for medical staffs and patients), sensor, and reacting system which receives the information regarding the number of medical staff and the status of the surgery, and controls the air volume of the HEPA air ventilation system accordingly. A pilot program was carried out in a unit of operation rooms of a medical center with 1,500 beds located in central Taiwan from Jan to Aug 2010. The results found the air ventilation system was able to function much more efficiently with less energy consumed. Furthermore, the indoor air quality could still keep qualified and hospital-acquired infection or other occupational diseases could be prevented.

Modeling and design of reacting systems with phase transfer catalysis

DEFF Research Database (Denmark)

Piccolo, Chiara; Hodges, George; Piccione, Patrick M.

2011-01-01

Issues related to the design of biphasic (liquid) catalytic reaction operations are discussed. A chemical system involving the reaction of an organic-phase soluble reactant (A) with an aqueous-phase soluble reactant (B) in the presence of phase transfer catalyst (PTC) is modeled and based on it......, some of the design issues related to improved reaction operation are analyzed. Since the solubility of the different forms of the PTC in the organic solvent affects ultimately the catalyst partition coefficients, therefore, the organic solvent plays an important role in the design of PTC-based reacting...

Mathematical aspects of reacting and diffusing systems

CERN Document Server

Fife, Paul C

1979-01-01

Modeling and analyzing the dynamics of chemical mixtures by means of differ- tial equations is one of the prime concerns of chemical engineering theorists. These equations often take the form of systems of nonlinear parabolic partial d- ferential equations, or reaction-diffusion equations, when there is diffusion of chemical substances involved. A good overview of this endeavor can be had by re- ing the two volumes by R. Aris (1975), who himself was one of the main contributors to the theory. Enthusiasm for the models developed has been shared by parts of the mathematical community, and these models have, in fact, provided motivation for some beautiful mathematical results. There are analogies between chemical reactors and certain biological systems. One such analogy is rather obvious: a single living organism is a dynamic structure built of molecules and ions, many of which react and diffuse. Other analogies are less obvious; for example, the electric potential of a membrane can diffuse like a chemical, and ...

Reacting to different types of concept drift: the Accuracy Updated Ensemble algorithm.

Science.gov (United States)

Brzezinski, Dariusz; Stefanowski, Jerzy

2014-01-01

Data stream mining has been receiving increased attention due to its presence in a wide range of applications, such as sensor networks, banking, and telecommunication. One of the most important challenges in learning from data streams is reacting to concept drift, i.e., unforeseen changes of the stream's underlying data distribution. Several classification algorithms that cope with concept drift have been put forward, however, most of them specialize in one type of change. In this paper, we propose a new data stream classifier, called the Accuracy Updated Ensemble (AUE2), which aims at reacting equally well to different types of drift. AUE2 combines accuracy-based weighting mechanisms known from block-based ensembles with the incremental nature of Hoeffding Trees. The proposed algorithm is experimentally compared with 11 state-of-the-art stream methods, including single classifiers, block-based and online ensembles, and hybrid approaches in different drift scenarios. Out of all the compared algorithms, AUE2 provided best average classification accuracy while proving to be less memory consuming than other ensemble approaches. Experimental results show that AUE2 can be considered suitable for scenarios, involving many types of drift as well as static environments.

Analyses and characterization of fossil carbonaceous materials for silicon production

Energy Technology Data Exchange (ETDEWEB)

Myrvaagnes, Viktor

2008-01-15

Production of high silicon alloys is carried out in submerged arc furnaces by reduction of silicon bearing oxides (typically quartz) with carbon materials. Carbonaceous materials like coal, coke, charcoal and woodchips are commonly used as reduction materials in the process. Primarily based on historical prices of charcoal compared to fossil reduction materials, the Norwegian Ferroalloy Industry has mostly been using coal and coke (char) as the source of carbon. From a process point of view, the most important role of the carbonaceous material is to react with SiO gas to produce SiC. The ability of the reduction materials to react with SiO gas can be measured and the value is recognized as the reactivity of the carbon source. Reactivity is one of the most important parameters in the smelting process and is commonly acknowledged to strongly affect both productivity and specific energy consumption. The main objectives of this work has been to establish methods to characterize the material properties of fossil carbonaceous reduction materials used in the silicon process and to evaluated how these properties affect the reactivity towards SiO gas. In order to accomplish these objectives, three run of mine (ROM) single seam coals which are particularly well suited for ferroalloy production were selected. Two Carboniferous coals from USA (Blue Gem) and Poland (Staszic) with similar rank, but significantly different composition as well as a Permian coal from Australia (Peak Downs) have been characterized by chemical- and petrographical methods. Blue Gem is a homogeneous coal, low in mineral inclusions and macerals of the inertinite group and determined to have a random vitrinite reflectance of 0.71 %. Staszic has a similar reflectance of vitrinite (0.72 %), but is determined to be a very inhomogeneous coal with both inertinite macerals and minerals embedded in the vitrinite matrix. Peak Downs has a random reflectance of vitrinite of 1.32 % and is hence the coal sample of

BETWEEN THE RIGHT AND THE COMMON. HOW GROUPS REACT TO SOCIALLY UNDESIRABLE BEHAVIOUR

Directory of Open Access Journals (Sweden)

Komendant-Brodowska Agata

2017-06-01

Full Text Available The aim of the paper is to analyse the relationship between group characteristics and the scope of reaction of the group to socially undesirable behaviour. Sometimes small groups or communities fail to react to undesirable or violent behaviour and their apathy can have devastating consequences. Such a situation can occur among co-workers witnessing workplace mobbing, or neighbours who do not react to a suspicion of domestic violence. Reasons for their inaction are diverse and can include fear, doubts concerning the necessity of such a reaction, and also conformity. In the paper I examine a seemingly favourable situation: I assume that reaction is costless and all the members of the group would like to react (internalised norm, but they also want to conform. In order to analyse the factors that can influence the scope of group reaction, a structurally embedded sequential coordination game was played for different initial conditions. Computer simulations were conducted for networks of a specific type (Erd¨os-R´enyi random graph. The main aim of the analysis was to identify non-structural and structural features of the group that can impede or even block the intervention of the group. There is a positive relationship between the scope of group reaction and the strength of the internalized norm, whereas the level of conformity affects the chances of group intervention in a negative way. Heterogeneity of the group is an important factor - the scope of reaction is higher when members of the group have different levels of norm internalisation and conformity. There is a non-linear relationship between network density and the scope of reaction. Both low and high density can make it harder for people to act.

Efficient removal of sulfur hexafluoride (SF6) through reacting with recycled electroplating sludge.

Science.gov (United States)

Zhang, Jia; Zhou, Ji Zhi; Liu, Qiang; Qian, Guangren; Xu, Zhi Ping

2013-06-18

This paper reports that recycled electroplating sludge is able to efficiently remove greenhouse gas sulfur hexafluoride (SF6). The removal process involves various reactions of SF6 with the recycled sludge. Remarkably, the sludge completely removed SF6 at a capacity of 1.10 mmol/g (SF6/sludge) at 600 °C. More importantly, the evolved gases were SO2, SiF4, and a limited amount of HF, with no toxic SOF4, SO2F2, or SF4 being detected. These generated gases can be readily captured and removed by NaOH solution. The reacted solids were further found to be various metal fluorides, thus revealing that SF6 removal takes place by reacting with various metal oxides and silicate in the sludge. Moreover, the kinetic investigation revealed that the SF6 reaction with the sludge is a first-order chemically controlled process. This research thus demonstrates that the waste electroplating sludge can be potentially used as an effective removal agent for one of the notorious greenhouse gases, SF6.

Modification of wheat gluten with citric acid to produce superabsorbent materials

Science.gov (United States)

Wheat gluten was reacted with citric acid to produce natural superabsorbent materials able to absorb up to 78 times its weight in water. The properties of the modified gluten samples were characterized using Fourier Transform Infra-red (FTIR) spectroscopy, thermogravimetric analysis, and water uptak...

DESIGN, FABRICATION AND TEST OF THE REACT AND WIND, NB(3)SN, LDX FLOATING COIL CONDUCTOR

International Nuclear Information System (INIS)

SMITH, B.A.; MICHAEL, P.C.; MINERVINI, J.V.; TAKAYASU, M.; SCHULTZ, J.H.; GREGORY, E.; PYON, T.; SAMPSON, W.B.; GHOSH, A.; SCANLAN, R.

2000-01-01

The Levitated Dipole Experiment (LDX) is a novel approach for studying magnetic confinement of a fusion plasma. In this approach, a superconducting ring coil is magnetically levitated for up to 8 hours a day in the center of a 5 meter diameter vacuum vessel. The levitated coil, with on-board helium supply, is called the gloating Coil (F-Coil). Although the maximum field at the coil is only 5.3 tesla, a react-and-wind Nb 3 Sn conductor was selected because the relatively high critical temperature will enable the coil to remain levitated while it warms from 5 K to 10 K. Since pre-reacted Nb 3 Sn tape is no longer commercially available, a composite conductor was designed that contains an 18 strand Nb 3 Sn Rutherford cable. The cable was reacted and then soldered into a structural copper channel that completes the conductor and also provides quench protection. The strain state of the cable was continuously controlled during fabrication steps such as: soldering into the copper channel, spooling, and coil winding, to prevent degradation of the critical current. Measurements of strand and cable critical currents are reported, as well as estimates of the effect of fabrication, winding and operating strains on critical current

Shock-induced chemistry in organic materials

Energy Technology Data Exchange (ETDEWEB)

Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

2011-01-20

The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

A framework for the design of reacting systems with phase transfer catalysis

DEFF Research Database (Denmark)

Piccolo, Chiara; Shaw, Andrew; Hodges, George

2012-01-01

A generic modelling framework for phase transition catalyst based reacting systems has been developed and converted into a software tool. The modelling framework accommodates models of different types representing different sub-systems of the PTCbased reactive system; databases of model parameters...... and carefully collected and checked (for thermodynamic consistency) experimentally measured data. The models, data and software have been tested on various PTC-based reactive systems. Illustrative examples are provided....

Materials for Nonlinear Optics Chemical Perspectives

Science.gov (United States)

1991-01-01

potassium iodide for 15 h at reflux. The benzaldehyde product was then allowed to react with diethyl(4-nitrobenzyl)phosphonate in the presence of ...photocrosslinking of NLO-inactive polyacrylate monomers. Recent advances in optical technology have created great interest in the construction of second-order...might be potassium niobate.) Because of this, the value of finding an "improved" material can be accurately gauged in a relative sense, and compared to

Effects of radiative heat transfer on the turbulence structure in inert and reacting mixing layers

International Nuclear Information System (INIS)

Ghosh, Somnath; Friedrich, Rainer

2015-01-01

We use large-eddy simulation to study the interaction between turbulence and radiative heat transfer in low-speed inert and reacting plane temporal mixing layers. An explicit filtering scheme based on approximate deconvolution is applied to treat the closure problem arising from quadratic nonlinearities of the filtered transport equations. In the reacting case, the working fluid is a mixture of ideal gases where the low-speed stream consists of hydrogen and nitrogen and the high-speed stream consists of oxygen and nitrogen. Both streams are premixed in a way that the free-stream densities are the same and the stoichiometric mixture fraction is 0.3. The filtered heat release term is modelled using equilibrium chemistry. In the inert case, the low-speed stream consists of nitrogen at a temperature of 1000 K and the highspeed stream is pure water vapour of 2000 K, when radiation is turned off. Simulations assuming the gas mixtures as gray gases with artificially increased Planck mean absorption coefficients are performed in which the large-eddy simulation code and the radiation code PRISSMA are fully coupled. In both cases, radiative heat transfer is found to clearly affect fluctuations of thermodynamic variables, Reynolds stresses, and Reynolds stress budget terms like pressure-strain correlations. Source terms in the transport equation for the variance of temperature are used to explain the decrease of this variance in the reacting case and its increase in the inert case

Identification of streptococcal proteins reacting with sera from Behçet's disease and rheumatic disorders.

Science.gov (United States)

Cho, Sung Bin; Lee, Ju Hee; Ahn, Keun Jae; Cho, Suhyun; Park, Yong-Beom; Lee, Soo-Kon; Bang, Dongsik; Lee, Kwang Hoon

2010-01-01

We evaluated the reactivity of sera from Behçet's disease (BD), systemic lupus erythematosus (SLE), dermatomyositis (DM), rheumatoid arthritis (RA), and Takayasu's arteritis (TA) patients against human α-enolase and streptococcal α-enolase, and identified additional streptococcal antigens. Enzyme-linked immunosorbent assay (ELISA) and immunoblotting were performed using sera from patients with BD, SLE, DM, RA, and TA and healthy volunteers (control) against human α-enolase and streptococcal α-enolase. Immunoblot analysis and matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry were used to identify and recombine other streptococcal antigens. Specific positive signals against recombinant human α-enolase were detected by IgM ELISA of serum samples from 50% of BD, 14.3% of SLE, 57.1% of DM, 42.9% of RA, and 57.1% of TA patients. Specific positive signals against streptococcal α-enolase were detected from 42.9% of BD, 14.3% of DM, and 14.3% of TA patients. No SLE and RA sera reacted against streptococcal α-enolase antigen. Streptococcal proteins reacting with sera were identified as hypothetical protein (HP) for SLE and DM patients, acid phosphatase (AP) for RA patients, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) for TA patients. We observed that RA patients did not present serum reactivity against either HP or GAPDH though BD, SLE, DM, and TA patients did. Also, AP reacted with sera from BD, SLE, DM, RA, and TA patients.

A mathematical model for chemical reactions with actinide elements in the aqueous nitric acid solution: REACT

International Nuclear Information System (INIS)

Tachimori, Shoichi

1990-02-01

A mathematical model of chemical reactions with actinide elements: REACT code, was developed to simulate change of valency states of U, Pu and Np in the aqueous nitric acid solution. Twenty seven rate equations for the redox reactions involving some reductants, disproportionation reactions, and radiolytic growth and decay reaction of nitrous acid were programmed in the code . Eight numerical solution methods such as Porsing method to solve the rate equations were incorporated parallel as options depending on the characteristics of the reaction systems. The present report gives a description of the REACT code, e.g., chemical reactions and their rate equations, numerical solution methods, and some examples of the calculation results. A manual and a source file of the program was attached to the appendix. (author)

PENGARUH MODEL PEMBELAJARAN INKUIRI BERSTRATEGI REACT TERHADAP HASIL BELAJAR KIMIA SISWA SMA KELAS XI

Directory of Open Access Journals (Sweden)

Riva Ismawati

2015-11-01

Full Text Available This study aimed to determine the effect of inquiry learning model with REACT strategy on learning outcomes and to determine the contribution to the learning outcomes. The expected benefits are improvements in learning chemistry subjects in class XI of high school through constructivism learning activities. The population in this study were students of class XI of high school in Semarang. The analysis showed the early stages of the population have the same degree of homogeneity and normal distribution. Average learning outcomes after experimental class treated were better than the control class, which amounted to 75.52 and 67.14. Test the difference between two average results obtained t from calculation (4.85> t from table (1.66, so we can conclude the experimental class learning results are better than the control class. Correlation test resulted biserial correlation coefficient (rb of 0.58 and t from calculation (5.68> t from table (1.99, so the influence was significant. Effect of application of inquiry learning model with REACT strategy shown by the coefficient of determination of 33.64%.The cognitive learning outcomes of experimental class had reached mastery learning classical while control class not yet. The average value of affective and psychomotor experimental classes are better than the control class. Based on these results, it can be concluded that the inquiry learning with REACT strategy have positive effect on learning outcomes chemistry in student class XI of high school in Semarang.

77 FR 67055 - Application for a Presidential Permit To Operate and Maintain Pipeline Facilities (Line 39) on...

Science.gov (United States)

2012-11-08

... NOVA Corporation are owned by a wholly owned subsidiary of the International Petroleum Investment... series of internal transactions, Polysar's direct parent was merged into NOVA Inc. and Polysar changed... non-gaseous fuels to or from a foreign country. The Department of State is circulating this...

Self-degradable Cementitious Sealing Materials

Energy Technology Data Exchange (ETDEWEB)

Sugama, T.; Butcher, T., Lance Brothers, Bour, D.

2010-10-01

A self-degradable alkali-activated cementitious material consisting of a sodium silicate activator, slag, Class C fly ash, and sodium carboxymethyl cellulose (CMC) additive was formulated as one dry mix component, and we evaluated its potential in laboratory for use as a temporary sealing material for Enhanced Geothermal System (EGS) wells. The self-degradation of alkali-activated cementitious material (AACM) occurred, when AACM heated at temperatures of {ge}200 C came in contact with water. We interpreted the mechanism of this water-initiated self-degradation as resulting from the in-situ exothermic reactions between the reactants yielded from the dissolution of the non-reacted or partially reacted sodium silicate activator and the thermal degradation of the CMC. The magnitude of self-degradation depended on the CMC content; its effective content in promoting degradation was {ge}0.7%. In contrast, no self-degradation was observed from CMC-modified Class G well cement. For 200 C-autoclaved AACMs without CMC, followed by heating at temperatures up to 300 C, they had a compressive strength ranging from 5982 to 4945 psi, which is {approx}3.5-fold higher than that of the commercial Class G well cement; the initial- and final-setting times of this AACM slurry at 85 C were {approx}60 and {approx}90 min. Two well-formed crystalline hydration phases, 1.1 nm tobermorite and calcium silicate hydrate (I), were responsible for developing this excellent high compressive strength. Although CMC is an attractive, as a degradation-promoting additive, its addition to both the AACM and the Class G well cement altered some properties of original cementitious materials; among those were an extending their setting times, an increasing their porosity, and lowering their compressive strength. Nevertheless, a 0.7% CMC-modified AACM as self-degradable cementitious material displayed the following properties before its breakdown by water; {approx}120 min initial- and {approx}180 min final

Errors of Students Learning With React Strategy in Solving the Problems of Mathematical Representation Ability

Directory of Open Access Journals (Sweden)

Delsika Pramata Sari

2017-06-01

Full Text Available The purpose of this study was to investigate the errors experienced by students learning with REACT strategy and traditional learning in solving problems of mathematical representation ability. This study used quasi experimental pattern with static-group comparison design. The subjects of this study were 47 eighth grade students of junior high school in Bandung consisting of two samples. The instrument used was a test to measure students' mathematical representation ability. The reliability coefficient about the mathematical representation ability was 0.56. The most prominent errors of mathematical representation ability of students learning with REACT strategy and traditional learning, was on indicator that solving problem involving arithmetic symbols (symbolic representation. In addition, errors were also experienced by many students with traditional learning on the indicator of making the image of a real world situation to clarify the problem and facilitate its completion (visual representation.

Acute hepatitis due to Epstein–Barr virus with cross-reacting antibodies to cytomegalovirus

Directory of Open Access Journals (Sweden)

Asli Karadeniz

2018-01-01

Full Text Available Epstein–Barr virus (EBV is the cause of systemic infection known as infectious mononucleosis with classic presentation of fever, oropharyngitis and lymphadenitis. EBV rarely causes acute hepatitis. In this report, we present a 19-year-old patient presented with nausea, fatigue and jaundice. Her physical examination and laboratory tests revealed the diagnosis as acute hepatitis due to EBV with cross-reacting antibodies to cytomegalovirus.

Investigation of the properties of fully reacted unstoichiometric polydimethylsiloxane networks and their extracted network fractions

DEFF Research Database (Denmark)

Frankær, Sarah Maria Grundahl; Jensen, Mette Krog; Bejenariu, Anca Gabriela

2012-01-01

We investigated the linear dynamic response of a series of fully reacted unstoichiometric polydimethylsiloxane (PDMS) networks and of the two corresponding network fractions namely the sol and the washed network. The sol and the washed network were separated by a simple extraction process. This way...

Fabrication of a Combustion-Reacted High-Performance ZnO Electron Transport Layer with Silver Nanowire Electrodes for Organic Solar Cells.

Science.gov (United States)

Park, Minkyu; Lee, Sang-Hoon; Kim, Donghyuk; Kang, Juhoon; Lee, Jung-Yong; Han, Seung Min

2018-02-28

Herein, a new methodology for solution-processed ZnO fabrication on Ag nanowire network electrode via combustion reaction is reported, where the amount of heat emitted during combustion was minimized by controlling the reaction temperature to avoid damaging the underlying Ag nanowires. The degree of participation of acetylacetones, which are volatile fuels in the combustion reaction, was found to vary with the reaction temperature, as revealed by thermogravimetric and compositional analyses. An optimized processing temperature of 180 °C was chosen to successfully fabricate a combustion-reacted ZnO and Ag nanowire hybrid electrode with a sheet resistance of 30 Ω/sq and transmittance of 87%. A combustion-reacted ZnO on Ag nanowire hybrid structure was demonstrated as an efficient transparent electrode and electron transport layer for the PTB7-Th-based polymer solar cells. The superior electrical conductivity of combustion-reacted ZnO, compared to that of conventional sol-gel ZnO, increased the external quantum efficiency over the entire absorption range, whereas a unique light scattering effect due to the presence of nanopores in the combustion-derived ZnO further enhanced the external quantum efficiency in the 450-550 nm wavelength range. A power conversion efficiency of 8.48% was demonstrated for the PTB7-Th-based polymer solar cell with the use of a combustion-reacted ZnO/Ag NW hybrid transparent electrode.

A Finite Element Theory for Predicting the Attenuation of Extended-Reacting Liners

Science.gov (United States)

Watson, W. R.; Jones, M. G.

2009-01-01

A non-modal finite element theory for predicting the attenuation of an extended-reacting liner containing a porous facesheet and located in a no-flow duct is presented. The mathematical approach is to solve separate wave equations in the liner and duct airway and to couple these two solutions by invoking kinematic constraints at the facesheet that are consistent with a continuum theory of fluid motion. Given the liner intrinsic properties, a weak Galerkin finite element formulation with cubic polynomial basis functions is used as the basis for generating a discrete system of acoustic equations that are solved to obtain the coupled acoustic field. A state-of-the-art, asymmetric, parallel, sparse equation solver is implemented that allows tens of thousands of grid points to be analyzed. A grid refinement study is presented to show that the predicted attenuation converges. Excellent comparison of the numerically predicted attenuation to that of a mode theory (using a Haynes 25 metal foam liner) is used to validate the computational approach. Simulations are also presented for fifteen porous plate, extended-reacting liners. The construction of some of the porous plate liners suggest that they should behave as resonant liners while the construction of others suggest that they should behave as broadband attenuators. In each case the finite element theory is observed to predict the proper attenuation trend.

A quasi-linear formulation for chemically reacting compressible mixtures of imperfect gases

Science.gov (United States)

Lentini, D.

2008-01-01

A quasi-linear formulation is proposed for high-speed finite-rate chemically reacting mixtures of imperfect gases, i.e., thermally perfect gases with specific heat varying with temperature. It retains the same formalism of a well-tried counterpart formulation for perfect gases, which has been proven to be suited for application of accurate and fast algorithms. Equations for both quasi-monodimensional flows, and for axisymmetric viscous flows are presented. The approach is based on the definition of an appropriate function F of temperature and concentration, which allows to identify Riemann variables for the flow under consideration; the formulation also includes equations for the entropy and the mass fractions of the N chemical species present in the reacting mixture. The key function F must be computed by numerical quadrature, together with its derivatives with respect to the individual species mass fractions. An example of computation of these quantities is reported, with reference to conditions in the combustion chamber of the Vulcain engine powering the first stage of the Ariane 5 launcher. Such a computation is demonstrated to be both economic and accurate, thus proving the workability of the proposed approach. Further, an estimate of the variation of the mixture specific heat ratio with temperature is given, in order to underline the importance of the effect under consideration.

Evaluation of a porcine internal mammary artery (No-React II) as a small-diameter conduit

NARCIS (Netherlands)

Ostapczuk, S; Poniewierski, J; Thiel, A; Knieriem, HJ; Orlowski, T; Rakhorst, G; Krian, A

1998-01-01

Background. The patency of biologic small-diameter vascular grafts in the aortocoronary position is still unsatisfactory. Most of the studies suggest that xeno-grafts are to be avoided as an aortocoronary bypass. Methods. The porcine internal mammary artery treated by the No-React II procedure was

Cross-reacting antibacterial auto-antibodies are produced within coronary atherosclerotic plaques of acute coronary syndrome patients.

Directory of Open Access Journals (Sweden)

Filippo Canducci

Full Text Available Coronary atherosclerosis, the main condition predisposing to acute myocardial infarction, has an inflammatory component caused by stimuli that are yet unknown. We molecularly investigated the nature of the immune response within human coronary lesion in four coronary plaques obtained by endoluminal atherectomy from four patients. We constructed phage-display libraries containing the IgG1/kappa antibody fragments produced by B-lymphocytes present in each plaque. By immunoaffinity, we selected from these libraries a monoclonal antibody, arbitrarily named Fab7816, able to react both with coronary and carotid atherosclerotic tissue samples. We also demonstrated by confocal microscopy that this monoclonal antibody recognized human transgelin type 1, a cytoskeleton protein involved in atherogenesis, and that it co-localized with fibrocyte-like cells transgelin+, CD68+, CD45+ in human sections of coronary and carotid plaques. In vitro fibrocytes obtained by differentiating CD14+ cells isolated from peripheral blood mononuclear cells also interacted with Fab7816, thus supporting the hypothesis of a specific recognition of fibrocytes into the atherosclerotic lesions. Interestingly, the same antibody, cross-reacted with the outer membrane proteins of Proteus mirabilis and Klebsiella pneumoniae (and possibly with homologous proteins of other enterobacteriaceae present in the microbiota. From all the other three libraries, we were able to clone, by immunoaffinity selection, human monoclonal antibodies cross-reacting with bacterial outer membrane proteins and with transgelin. These findings demonstrated that in human atherosclerotic plaques a local cross-reactive immune response takes place.

Competitor's marketing : How banks acquire and react to knowledge about their competitor's marketing.

OpenAIRE

Puelma, Rodrigo; Persson, Annika

2008-01-01

Abstract   Introduction The way banks compete has changed dramatically during recent years, mostly because of international trends such as advances in information technology, globalisation and deregulations. This has made competition harsher meaning that survival and success requires knowledge about the competitors and understanding about the way they act and react. Within marketing there is a need to identify suitable strategies to acquire knowledge about competitor’s marketing and methods t...

Processing method and device for iodine adsorbing material

International Nuclear Information System (INIS)

Watanabe, Shin-ichi; Shiga, Reiko.

1997-01-01

An iodine adsorbing material adsorbing silver compounds is reacted with a reducing gas, so that the silver compounds are converted to metal silver and stored. Then, the silver compounds are not melted or recrystallized even under a highly humid condition, accordingly, peeling of the adsorbed materials from a carrier can be prevented, and the iodine adsorbing material can be stored stably. Since the device is disposed in an off gas line for discharging off gases from a nuclear power facility, the iodine adsorbing material formed by depositing silver halides to the carrier is contained, and a reducing or oxidizing gas is supplied to the vessel as required, and silver halides can be converted to metal silver or the metal silver can be returned to silver halide. (T.M.)

Microhardness and Strain Field Characterization of Self-Reacting Friction Stir and Plug Welds of Dissimilar Aluminum Alloys

Science.gov (United States)

Horton, Karla Renee

2011-01-01

Friction stir welding (FSW) is a solid state welding process with potential advantages for aerospace and automotive industries dealing with light alloys. Self-reacting friction stir welding (SR-FSW) is one variation of the FSW process being developed at the National Aeronautics and Space Administration (NASA) for use in the fabrication of propellant tanks. Friction plug welding is used to seal the exit hole that remains in a circumferential SR-FSW. This work reports on material properties and strain patterns developed in a SR-FSW with a friction plug weld. Specifically, this study examines the behavior of a SR-FSW formed between an AA 2014-T6 plate on the advancing side and an AA 2219-T87 plate on the retreating side and a SR-FSW (AA 2014-T6 to AA 2219-T87) with a 2219-T87 plug weld. This study presents the results of a characterization of the micro-hardness, joint strength, and strain field characterization of SR-FSW and FPW joints tested at room temperature and cryogenic temperatures.

'Reacting to the unknown': experiencing the first birth at home or in hospital in Australia.

Science.gov (United States)

Dahlen, Hannah G; Barclay, Lesley; Homer, Caroline S E

2010-08-01

to explore the experiences of a small group of first-time mothers giving birth at home or in hospital. a grounded theory methodology was used. Data were generated from in-depth interviews with women in their own homes. Sydney, Australia. 19 women were interviewed. Seven women who gave birth for the first time in a public hospital and seven women who gave birth for the first time at home were interviewed, and their experiences were contrasted with two mothers who gave birth for the first time in a birth centre, one mother who gave birth for the first time in a private hospital and two women who had given birth more than once. these women shared common experiences of giving birth as 'novices'. Regardless of birth setting, they were all 'reacting to the unknown'. As they entered labour, the women chose different levels of responsibility for their birth. They also readjusted their expectations when the reality of labour occurred, reacted to the 'force' of labour, and connected or disconnected from the labour and eventually the baby. knowing that first-time mothers, irrespective of birth setting, are essentially 'reacting to the unknown' as they negotiate the experience of birth, could alter the way in which care is provided and increase the sensitivity of midwives to women's needs. Most importantly, midwives need to be aware of the need to help women adjust their expectations during labour and birth. Identifying the 'novice' status of first-time mothers also better explains previous research that reports unrealistic expectations and fear that may be associated with first-time birthing. Crown Copyright 2008. Published by Elsevier Ltd. All rights reserved.

A Parallel Multiblock Structured Grid Method with Automated Interblocked Unstructured Grids for Chemically Reacting Flows

Science.gov (United States)

Spiegel, Seth Christian

An automated method for using unstructured grids to patch non- C0 interfaces between structured blocks has been developed in conjunction with a finite-volume method for solving chemically reacting flows on unstructured grids. Although the standalone unstructured solver, FVFLO-NCSU, is capable of resolving flows for high-speed aeropropulsion devices with complex geometries, unstructured-mesh algorithms are inherently inefficient when compared to their structured counterparts. However, the advantages of structured algorithms in developing a flow solution in a timely manner can be negated by the amount of time required to develop a mesh for complex geometries. The global domain can be split up into numerous smaller blocks during the grid-generation process to alleviate some of the difficulties in creating these complex meshes. An even greater abatement can be found by allowing the nodes on abutting block interfaces to be nonmatching or non-C 0 continuous. One code capable of solving chemically reacting flows on these multiblock grids is VULCAN, which uses a nonconservative approach for patching non-C0 block interfaces. The developed automated unstructured-grid patching algorithm has been installed within VULCAN to provide it the capability of a fully conservative approach for patching non-C0 block interfaces. Additionally, the FVFLO-NCSU solver algorithms have been deeply intertwined with the VULCAN source code to solve chemically reacting flows on these unstructured patches. Finally, the CGNS software library was added to the VULCAN postprocessor so structured and unstructured data can be stored in a single compact file. This final upgrade to VULCAN has been successfully installed and verified using test cases with particular interest towards those involving grids with non- C0 block interfaces.

"Reacting to the Past" to Be Proactive in the Present: Feminist Roots of High-Impact Practices

Science.gov (United States)

Lidinsky, April

2014-01-01

In this article, the author explains a high-impact role-playing pedagogy developed at Barnard College called "Reacting to the Past," which she uses to introduce first-year and general education students to feminist history, current feminist issues, and feminist pedagogy.

Desarrollo de una aplicación móvil mediante React-Native

OpenAIRE

Raja Lentijo, David

2018-01-01

In this document has been developed an application to share food recipes with social format where the users can interact between them. The goal of this applications is to create a global platform when users wants to find something related with cooking, know where have to go and don't have to use a web browser. All has developed with React-Native that allows to develop native applications for Android and IOS platforms, and reduce the processing time respect to hybrid applications. Also, the co...

Errors of Students Learning with React Strategy in Solving the Problems of Mathematical Representation Ability

Science.gov (United States)

Sari, Delsika Pramata; Darhim; Rosjanuardi, Rizky

2018-01-01

The purpose of this study was to investigate the errors experienced by students learning with REACT strategy and traditional learning in solving problems of mathematical representation ability. This study used quasi experimental pattern with static-group comparison design. The subjects of this study were 47 eighth grade students of junior high…

Nanocomposite anode materials for sodium-ion batteries

Science.gov (United States)

Manthiram, Arumugam; Kim Il, Tae; Allcorn, Eric

2016-06-14

The disclosure relates to an anode material for a sodium-ion battery having the general formula AO.sub.x--C or AC.sub.x--C, where A is aluminum (Al), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W), niobium (Nb), tantalum (Ta), silicon (Si), or any combinations thereof. The anode material also contains an electrochemically active nanoparticles within the matrix. The nanoparticle may react with sodium ion (Na.sup.+) when placed in the anode of a sodium-ion battery. In more specific embodiments, the anode material may have the general formula M.sub.ySb-M'O.sub.x--C, Sb-MO.sub.x--C, M.sub.ySn-M'C.sub.x--C, or Sn-MC.sub.x--C. The disclosure also relates to rechargeable sodium-ion batteries containing these materials and methods of making these materials.

Combined LAURA-UPS solution procedure for chemically-reacting flows. M.S. Thesis

Science.gov (United States)

Wood, William A.

1994-01-01

A new procedure seeks to combine the thin-layer Navier-Stokes solver LAURA with the parabolized Navier-Stokes solver UPS for the aerothermodynamic solution of chemically-reacting air flowfields. The interface protocol is presented and the method is applied to two slender, blunted shapes. Both axisymmetric and three dimensional solutions are included with surface pressure and heat transfer comparisons between the present method and previously published results. The case of Mach 25 flow over an axisymmetric six degree sphere-cone with a noncatalytic wall is considered to 100 nose radii. A stability bound on the marching step size was observed with this case and is attributed to chemistry effects resulting from the noncatalytic wall boundary condition. A second case with Mach 28 flow over a sphere-cone-cylinder-flare configuration is computed at both two and five degree angles of attack with a fully-catalytic wall. Surface pressures are seen to be within five percent with the present method compared to the baseline LAURA solution and heat transfers are within 10 percent. The effect of grid resolution is investigated and the nonequilibrium results are compared with a perfect gas solution, showing that while the surface pressure is relatively unchanged by the inclusion of reacting chemistry the nonequilibrium heating is 25 percent higher. The procedure demonstrates significant, order of magnitude reductions in solution time and required memory for the three dimensional case over an all thin-layer Navier-Stokes solution.

21 CFR 886.4275 - Intraocular fluid.

Science.gov (United States)

2010-04-01

... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4275 Intraocular fluid. (a) Identification. An intraocular fluid is a device consisting of a nongaseous fluid intended to be introduced into the eye to aid... section 515 of the act is required before this device may be commercially distributed. See § 886.3. ...

78 FR 29201 - Notice of Availability of Finding of No Significant Impact for the Proposed Vantage Pipeline US...

Science.gov (United States)

2013-05-17

... Impact for the Proposed Vantage Pipeline US LP Ethane Pipeline Project SUMMARY: The purpose of this... Impact on the proposed Vantage Pipeline US LP Ethane Pipeline Project. Under E.O. 13337, the Secretary of... petroleum, petroleum products, or other non-gaseous fuels to or from a foreign country. Vantage Pipeline US...

Turbulent diffusion of chemically reacting flows: Theory and numerical simulations.

Science.gov (United States)

Elperin, T; Kleeorin, N; Liberman, M; Lipatnikov, A N; Rogachevskii, I; Yu, R

2017-11-01

The theory of turbulent diffusion of chemically reacting gaseous admixtures developed previously [T. Elperin et al., Phys. Rev. E 90, 053001 (2014)PLEEE81539-375510.1103/PhysRevE.90.053001] is generalized for large yet finite Reynolds numbers and the dependence of turbulent diffusion coefficient on two parameters, the Reynolds number and Damköhler number (which characterizes a ratio of turbulent and reaction time scales), is obtained. Three-dimensional direct numerical simulations (DNSs) of a finite-thickness reaction wave for the first-order chemical reactions propagating in forced, homogeneous, isotropic, and incompressible turbulence are performed to validate the theoretically predicted effect of chemical reactions on turbulent diffusion. It is shown that the obtained DNS results are in good agreement with the developed theory.

Therapeutic preparations of IVIg contain naturally occurring anti-HLA-E antibodies that react with HLA-Ia (HLA-A/-B/-Cw) alleles.

Science.gov (United States)

Ravindranath, Mepur H; Terasaki, Paul I; Pham, Tho; Jucaud, Vadim; Kawakita, Satoru

2013-03-14

The US Food and Drug Administration approved intravenous immunoglobulin (IVIg), extracted from the plasma of thousands of blood donors, for removing HLA antibodies (Abs) in highly sensitized patients awaiting organ transplants. Since the blood of healthy individuals has HLA Abs, we tested different IVIg preparations for reactivity to HLA single antigen Luminex beads. All preparations showed high levels of HLA-Ia and -Ib reactivity. Since normal nonalloimmunized males have natural antibodies to the heavy chains (HCs) of HLA antigens, the preparations were then tested against iBeads coated only with intact HLA antigens. All IVIg preparations varied in level of antibody reactivity to intact HLA antigens. We raised monoclonal Abs against HLA-E that mimicked IVIg's HLA-Ia and HLA-Ib reactivity but reacted only to HLA-I HCs. Inhibition experiments with synthetic peptides showed that HLA-E shares epitopes with HLA-Ia alleles. Importantly, depleting anti-HLA-E Abs from IVIg totally eliminated the HLA-Ia reactivity of IVIg. Since anti-HLA-E mAbs react with HLA-Ia, they might be useful in suppressing HLA antibody production, similar to the way anti-RhD Abs suppress production. At the same time, anti-HLA-E mAb, which reacts only to HLA-I HCs, is unlikely to produce transfusion-related acute lung injury, in contrast to antibodies reacting to intact-HLA.

Lean premixed reacting flows with swirl and wall-separation zones in a contracting chamber

Science.gov (United States)

Zhang, Yuxin; Rusak, Zvi; Wang, Shixiao

2017-11-01

Low Mach number lean premixed reacting swirling flows with wall-separation zones in a contracting circular finite-length open chamber are studied. Assuming a complete reaction with high activation energy and chemical equilibrium behind the reaction zone, a nonlinear partial differential equation is derived for the solution of the flow stream function behind the reaction zone in terms of the inlet total enthalpy for a reacting flow, specific entropy and the circulation functions. Bifurcation diagrams of steady flows are described as the inlet swirl level is increased at fixed chamber contraction and reaction heat release. The approach is applied to an inlet solid-body rotation flow with constant profiles of the axial velocity, temperature and mixture reactant mass fraction. The computed results provide predictions of the critical inlet swirl levels for the first appearance of wall-separation states and for the size of the separation zone as a function of the inlet swirl ratio, Mach number, chamber contraction and heat release of the reaction. The methodology developed in this paper provides a theoretical feasibility for the development of the technology of swirl-assisted combustion where the reaction zone is supported and stabilized by a wall-separation zone.

Biosmart Materials: Breaking New Ground in Dentistry

Directory of Open Access Journals (Sweden)

Vijetha Badami

2014-01-01

Full Text Available By definition and general agreement, smart materials are materials that have properties which may be altered in a controlled fashion by stimuli, such as stress, temperature, moisture, pH, and electric or magnetic fields. There are numerous types of smart materials, some of which are already common. Examples include piezoelectric materials, which produce a voltage when stress is applied or vice versa, shape memory alloys or shape memory polymers which are thermoresponsive, and pH sensitive polymers which swell or shrink as a response to change in pH. Thus, smart materials respond to stimuli by altering one or more of their properties. Smart behaviour occurs when a material can sense some stimulus from its environment and react to it in a useful, reliable, reproducible, and usually reversible manner. These properties have a beneficial application in various fields including dentistry. Shape memory alloys, zirconia, and smartseal are examples of materials exhibiting a smart behavior in dentistry. There is a strong trend in material science to develop and apply these intelligent materials. These materials would potentially allow new and groundbreaking dental therapies with a significantly enhanced clinical outcome of treatments.

Biosmart Materials: Breaking New Ground in Dentistry

Science.gov (United States)

Badami, Vijetha; Ahuja, Bharat

2014-01-01

By definition and general agreement, smart materials are materials that have properties which may be altered in a controlled fashion by stimuli, such as stress, temperature, moisture, pH, and electric or magnetic fields. There are numerous types of smart materials, some of which are already common. Examples include piezoelectric materials, which produce a voltage when stress is applied or vice versa, shape memory alloys or shape memory polymers which are thermoresponsive, and pH sensitive polymers which swell or shrink as a response to change in pH. Thus, smart materials respond to stimuli by altering one or more of their properties. Smart behaviour occurs when a material can sense some stimulus from its environment and react to it in a useful, reliable, reproducible, and usually reversible manner. These properties have a beneficial application in various fields including dentistry. Shape memory alloys, zirconia, and smartseal are examples of materials exhibiting a smart behavior in dentistry. There is a strong trend in material science to develop and apply these intelligent materials. These materials would potentially allow new and groundbreaking dental therapies with a significantly enhanced clinical outcome of treatments. PMID:24672407

Approximate solution to the Kolmogorov equation for a fission chain-reacting system

International Nuclear Information System (INIS)

Ruby, L.; McSwine, T.L.

1986-01-01

An approximate solution has been obtained for the Kolmogorov equation describing a fission chain-reacting system. The method considers the population of neutrons, delayed-neutron precursors, and detector counts. The effect of the detector is separated from the statistics of the chain reaction by a weak coupling assumption that predicts that the detector responds to the average rather than to the instantaneous neutron population. An approximate solution to the remaining equation, involving the populations of neutrons and precursors, predicts a negative-binomial behaviour for the neutron probability distribution

Extension of a semi-implicit shock-capturing algorithm for 3-D fully coupled, chemically reacting flows in generalized coordinates

International Nuclear Information System (INIS)

Shinn, J.L.; Yee, H.C.; Uenishi, K.; NASA, Ames Research Center, Moffett Field, CA; Vigyan Research Associates, Inc., Hampton, VA)

1987-01-01

A semiimplicit high-resolution shock-capturing method for multidimensional systems of hyperbolic conservation laws with stiff source terms has been developed by Yee and Shinn (1987). The goal of this work is to extend this method to solve the three-dimensional fully coupled Navier-Stokes equations for a hypersonic chemically reacting flow in generalized coordinates. In this formulation, the global continuity equation was replaced by all the species continuity equations. The shock-capturing technique is a second-order-accurate, symmetric total-variation-diminishing method which accounts fully and directly for the coupling among the fluid and all the species. To verify the current approach, it was implemented into an existing computer code which contained the MacCormack method. Test results for a five-species reacting flow are shown to be oscillation-free around the shock, and the time spent per iteration only doubles when compared to the result using classical way of supplying numerical dissipation. The extra computation is more than justified by the elimination of spurious oscillation and nonlinear instability associated with the classical shock-capturing schemes in computing hypersonic reacting flows. 27 references

Reaction Ensemble Molecular Dynamics: Direct Simulation of the Dynamic Equilibrium Properties of Chemically Reacting Mixtures

Czech Academy of Sciences Publication Activity Database

Brennan, J.K.; Lísal, Martin; Gubbins, K.E.; Rice, B.M.

2004-01-01

Roč. 70, č. 6 (2004), 0611031-0611034 ISSN 1063-651X R&D Projects: GA ČR GA203/03/1588 Grant - others:NSF(US) CTS-0211792 Institutional research plan: CEZ:AV0Z4072921 Keywords : reacting systems * simulation * molecular dynamics Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.352, year: 2004

Computer program to solve two-dimensional shock-wave interference problems with an equilibrium chemically reacting air model

Science.gov (United States)

Glass, Christopher E.

1990-08-01

The computer program EASI, an acronym for Equilibrium Air Shock Interference, was developed to calculate the inviscid flowfield, the maximum surface pressure, and the maximum heat flux produced by six shock wave interference patterns on a 2-D, cylindrical configuration. Thermodynamic properties of the inviscid flowfield are determined using either an 11-specie, 7-reaction equilibrium chemically reacting air model or a calorically perfect air model. The inviscid flowfield is solved using the integral form of the conservation equations. Surface heating calculations at the impingement point for the equilibrium chemically reacting air model use variable transport properties and specific heat. However, for the calorically perfect air model, heating rate calculations use a constant Prandtl number. Sample calculations of the six shock wave interference patterns, a listing of the computer program, and flowcharts of the programming logic are included.

Development and testing of bumper limiter of aluminum alloy vacuum vessel for reacting plasma experiment

International Nuclear Information System (INIS)

Uchikawa, T.; Fujiwara, M.; Ioki, K.; Irie, T.; Nayama, R.; Nishikawa, M.; Onozuka, M.; Tomita, M.

1985-01-01

Two types of graphite bumper limiters were designed and trially fabricated for a reacting plasma device, R-tokamak. High heat load tests were conducted to examine thermal behavior and thermal shock resistance of the limiters by using a 100kW electron beam facility. The experimental data were compared with the results of 3-D thermal analysis

Development and testing of bumper limiter of aluminum alloy vacuum vessel for reacting plasma experiment

Energy Technology Data Exchange (ETDEWEB)

Uchikawa, T.; Fujiwara, M.; Ioki, K.; Irie, T.; Nayama, R.; Nishikawa, M.; Onozuka, M.; Tomita, M.

1985-07-01

Two types of graphite bumper limiters were designed and trially fabricated for a reacting plasma device, R-tokamak. High heat load tests were conducted to examine thermal behavior and thermal shock resistance of the limiters by using a 100kW electron beam facility. The experimental data were compared with the results of 3-D thermal analysis.

Statistical analysis of the velocity and scalar fields in reacting turbulent wall-jets

Science.gov (United States)

Pouransari, Z.; Biferale, L.; Johansson, A. V.

2015-02-01

The concept of local isotropy in a chemically reacting turbulent wall-jet flow is addressed using direct numerical simulation (DNS) data. Different DNS databases with isothermal and exothermic reactions are examined. The chemical reaction and heat release effects on the turbulent velocity, passive scalar, and reactive species fields are studied using their probability density functions (PDFs) and higher order moments for velocities and scalar fields, as well as their gradients. With the aid of the anisotropy invariant maps for the Reynolds stress tensor, the heat release effects on the anisotropy level at different wall-normal locations are evaluated and found to be most accentuated in the near-wall region. It is observed that the small-scale anisotropies are persistent both in the near-wall region and inside the jet flame. Two exothermic cases with different Damköhler numbers are examined and the comparison revealed that the Damköhler number effects are most dominant in the near-wall region, where the wall cooling effects are influential. In addition, with the aid of PDFs conditioned on the mixture fraction, the significance of the reactive scalar characteristics in the reaction zone is illustrated. We argue that the combined effects of strong intermittency and strong persistency of anisotropy at the small scales in the entire domain can affect mixing and ultimately the combustion characteristics of the reacting flow.

Metallization for Yb14MnSb11-Based Thermoelectric Materials

Science.gov (United States)

Firdosy, Samad; Li, Billy Chun-Yip; Ravi, Vilupanur; Sakamoto, Jeffrey; Caillat, Thierry; Ewell, Richard C.; Brandon, Erik J.

2011-01-01

Thermoelectric materials provide a means for converting heat into electrical power using a fully solid-state device. Power-generating devices (which include individual couples as well as multicouple modules) require the use of ntype and p-type thermoelectric materials, typically comprising highly doped narrow band-gap semiconductors which are connected to a heat collector and electrodes. To achieve greater device efficiency and greater specific power will require using new thermoelectric materials, in more complex combinations. One such material is the p-type compound semiconductor Yb14MnSb11 (YMS), which has been demonstrated to have one of the highest ZT values at 1,000 C, the desired operational temperature of many space-based radioisotope thermoelectric generators (RTGs). Despite the favorable attributes of the bulk YMS material, it must ultimately be incorporated into a power-generating device using a suitable joining technology. Typically, processes such as diffusion bonding and/or brazing are used to join thermoelectric materials to the heat collector and electrodes, with the goal of providing a stable, ohmic contact with high thermal conductivity at the required operating temperature. Since YMS is an inorganic compound featuring chemical bonds with a mixture of covalent and ionic character, simple metallurgical diffusion bonding is difficult to implement. Furthermore, the Sb within YMS readily reacts with most metals to form antimonide compounds with a wide range of stoichiometries. Although choosing metals that react to form high-melting-point antimonides could be employed to form a stable reaction bond, it is difficult to limit the reactivity of Sb in YMS such that the electrode is not completely consumed at an operating temperature of 1,000 C. Previous attempts to form suitable metallization layers resulted in poor bonding, complete consumption of the metallization layer or fracture within the YMS thermoelement (or leg).

Vorticity Dynamics in Single and Multiple Swirling Reacting Jets

Science.gov (United States)

Smith, Travis; Aguilar, Michael; Emerson, Benjamin; Noble, David; Lieuwen, Tim

2015-11-01

This presentation describes an analysis of the unsteady flow structures in two multinozzle swirling jet configurations. This work is motivated by the problem of combustion instabilities in premixed flames, a major concern in the development of modern low NOx combustors. The objective is to compare the unsteady flow structures in these two configurations for two separate geometries and determine how certain parameters, primarily distance between jets, influence the flow dynamics. The analysis aims to differentiate between the flow dynamics of single nozzle and triple nozzle configurations. This study looks at how the vorticity in the shear layers of one reacting swirling jet can affect the dynamics of a nearby similar jet. The distance between the swirling jets is found to have an effect on the flow field in determining where swirling jets merge and on the dynamics upstream of the merging location. Graduate Student, School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA.

The impact of administration of conjugate vaccines containing cross reacting material on Haemophilus influenzae type b antibody responses in infants: A systematic review and meta-analysis of randomised controlled trials.

Science.gov (United States)

Voysey, Merryn; Sadarangani, Manish; Clutterbuck, Elizabeth; Bolgiano, Barbara; Pollard, Andrew J

2016-07-25

Protein-polysaccharide conjugate vaccines such as Haemophilus influenzae type b (Hib), meningococcal, and pneumococcal vaccine, induce immunological memory and longer lasting protection than plain polysaccharide vaccines. The most common proteins used as carriers are tetanus toxoid (TT) and cross reacting material-197 (CRM), a mutant form of diphtheria toxoid. CRM conjugate vaccines have been reported to suppress antibody responses to co-administered Hib-TT vaccine. We conducted a systematic review and meta-analysis of randomised controlled trials in which infants were randomised to receive meningococcal or pneumococcal conjugate vaccines along with Hib-TT. Trials of licensed vaccines with different carrier proteins were included for group C meningococcal (MenC), quadrivalent ACWY meningococcal (MenACWY), and pneumococcal vaccines. Twenty-three trials were included in the meta-analyses. Overall, administration of MenC-CRM in a 2 or 3 dose schedule resulted in a 45% reduction in Hib antibody concentrations (GMR 0.55, 95% CI 0.49-0.62). MenACWY-CRM boosted Hib antibody responses by 22% (GMR 1.22, 95% CI 1.06-1.41) whilst pneumococcal CRM conjugate vaccines had no impact on Hib antibody responses (GMR 0.91, 95% CI 0.68-1.22). The effect of CRM protein-polysaccharide conjugate vaccines on Hib antibody responses varies greatly between vaccines. Co-administration of a CRM conjugate vaccine can produce either positive or negative effects on Hib antibody responses. These inconsistencies suggest that CRM itself may not be the main driver of variability in Hib responses, and challenge current perspectives on this issue. Copyright © 2016 Elsevier Ltd. All rights reserved.

Doppler-shifted fluorescence imaging of velocity fields in supersonic reacting flows

Science.gov (United States)

Allen, M. G.; Davis, S. J.; Kessler, W. J.; Sonnenfroh, D. M.

1992-01-01

The application of Doppler-shifted fluorescence imaging of velocity fields in supersonic reacting flows is analyzed. Focussing on fluorescence of the OH molecule in typical H2-air Scramjet flows, the effects of uncharacterized variations in temperature, pressure, and collisional partner composition across the measurement plane are examined. Detailed measurements of the (1,0) band OH lineshape variations in H2-air combustions are used, along with single-pulse and time-averaged measurements of an excimer-pumped dye laser, to predict the performance of a model velocimeter with typical Scramjet flow properties. The analysis demonstrates the need for modification and control of the laser bandshape in order to permit accurate velocity measurements in the presence of multivariant flow properties.

Approximate method of calculation of non-equilibrium flow parameters of chemically reacting nitrogen tetroxide in the variable cross-section channels with energy exchange

International Nuclear Information System (INIS)

Bazhin, M.A.; Fedosenko, G.Eh.; Shiryaeva, N.M.; Mal'ko, M.V.

1986-01-01

It is shown that adiabatic non-equilibrium chemically reacting gas flow with energy exchange in a variable cross-section channel may be subdivided into five possible types: 1) quasi-equilibrium flow; 2) flow in the linear region of deviation from equilibrium state; 3) quasi-frozen flow; 4) flow in the linear region of deviation from frozen state; 5) non-equilibrium flow. Criteria of quasi-equilibrium and quazi-frozen flows, including factors of external action of chemically reacting gas on flow, allow to obtain simple but sufficiently reliable approximate method of calculation of flow parameters. The considered method for solving the problem of chemically reacting nitrogen tetroxide in the variable cross-section channel with energy exchange can be used for evaluation of chemical reaction kinetics on the flow parameter in the stages of axial-flow and radial-flow turbines and in another practical problems

Outcomes in Patients With Metastatic Renal Cell Carcinoma Who Develop Everolimus-Related Hyperglycemia and Hypercholesterolemia: Combined Subgroup Analyses of the RECORD-1 and REACT Trials.

Science.gov (United States)

Bono, Petri; Oudard, Stephane; Bodrogi, Istvan; Hutson, Thomas E; Escudier, Bernard; Machiels, Jean-Pascal; Thompson, John A; Figlin, Robert A; Ravaud, Alain; Basaran, Mert; Porta, Camillo; Bracarda, Sergio; Brechenmacher, Thomas; Lin, Chinjune; Voi, Maurizio; Grunwald, Viktor; Motzer, Robert J

2016-10-01

Hyperglycemia and hypercholesterolemia are class effects of mammalian target of rapamycin inhibitors. The purpose of this study was to characterize safety and efficacy of patients with metastatic renal cell carcinoma (mRCC) treated with everolimus in RECORD-1 (REnal Cell cancer treatment with Oral RAD001 given Daily) and REACT (RAD001 Expanded Access Clinical Trial in RCC) who developed these events. Adults with vascular endothelial growth factor-refractory mRCC received everolimus 10 mg/d in the randomized RECORD-1 (n = 277) and open-label REACT (n = 1367) studies. Outcomes included safety, treatment duration, overall response, and progression-free survival for patients who developed hypercholesterolemia or hyperglycemia. In RECORD-1, 12% (33 of 277) and 20% (55 of 277) of patients developed any grade hyperglycemia or hypercholesterolemia, respectively, with only 6% (78 of 1367) and 1% (14 of 1367) of the same events, respectively, in REACT. Median everolimus treatment duration was similar for patients with hyperglycemia or hypercholesterolemia (RECORD-1, 6.2 and 6.2 months, respectively; REACT, 4.4 and 4.5 months, respectively), but longer than the overall populations (RECORD-1, 4.6 months; REACT, 3.2 months). In RECORD-1/REACT, 82%/68% of patients with hyperglycemia and 75%/71% of patients with hypercholesterolemia achieved partial response or stable disease. The incidence of clinically notable Grade 3 or 4 adverse events, other than anemia and lymphopenia, appeared to be similar across trials and subgroups. Although there was a trend for improved progression-free survival with development of hyperglycemia or hypercholesterolemia, the association was not statistically significant. Hyperglycemia and hypercholesterolemia were observed in low numbers of patients, and although these events might be associated with improved response to everolimus, the differences were not significant. These findings should be validated with prospective biomarker studies. Copyright

Towards an Articulation of the Material and Visual Turn in Organization Studies

DEFF Research Database (Denmark)

Boxenbaum, Eva; Jones, Candace; Meyer, Renate

2018-01-01

Contemporary organizations increasingly rely on images, logos, videos, building materials, graphic and product design, and a range of other material and visual artifacts to compete, communicate, form identity and organize their activities. This Special Issue focuses on materiality and visuality...... on the articles in the special issue, we further explore the affordances and limits of the material and visual dimensions of organizing in relation to novelty. We conclude by pointing out theoretical avenues for advancing multimodal research, and discuss some of the ethical, pragmatic and identity...... in the course of objectifying and reacting to novel ideas, and, more broadly, contributes to organizational theory by articulating the emergent contours of a material and visual turn in the study of organizations. In this Introduction, we provide an overview of research on materiality and visuality. Drawing...

How preschoolers react to norm violations is associated with culture.

Science.gov (United States)

Gampe, Anja; Daum, Moritz M

2018-01-01

Children from the age of 3years understand social norms as such and enforce these norms in interactions with others. Differences in parental and institutional education across cultures make it likely that children receive divergent information about how to act in cases of norm violations. In the current study, we investigated whether cultural values are associated with the ways in which children react to norm violations. We tested 80 bicultural 3-year-olds with a norm enforcement paradigm and analyzed their reactions to norm violations. The reactions were correlated to the children's parental cultural values using the Global Leadership and Organizational Behavior Effectiveness (GLOBE) scales, and these results show that parental culture was associated with children's reactions to norm violations. The three strongest correlations were found for institutional collectivism, performance orientation, and assertiveness. Copyright © 2017 Elsevier Inc. All rights reserved.

Methods for purifying carbon materials

Science.gov (United States)

Dailly, Anne [Pasadena, CA; Ahn, Channing [Pasadena, CA; Yazami, Rachid [Los Angeles, CA; Fultz, Brent T [Pasadena, CA

2009-05-26

Methods of purifying samples are provided that are capable of removing carbonaceous and noncarbonaceous impurities from a sample containing a carbon material having a selected structure. Purification methods are provided for removing residual metal catalyst particles enclosed in multilayer carbonaceous impurities in samples generate by catalytic synthesis methods. Purification methods are provided wherein carbonaceous impurities in a sample are at least partially exfoliated, thereby facilitating subsequent removal of carbonaceous and noncarbonaceous impurities from the sample. Methods of purifying carbon nanotube-containing samples are provided wherein an intercalant is added to the sample and subsequently reacted with an exfoliation initiator to achieve exfoliation of carbonaceous impurities.

PERBEDAAN KEMAMPUAN KONEKSI MATEMATIS MELALUI MODEL PEMBELAJARAN REACT DENGAN MODEL PEMBELAJARAN LEARNING CYCLE 5E SISWA SMKN 39 JAKARTA

Directory of Open Access Journals (Sweden)

Aditya Prihandhika

2017-03-01

Full Text Available Hasil analisa TIMSS Tahun 2013 menempatkan Indonesia sebagai salah satu negara dengan peringkat terendah dalam perolehan nilai matematika. Model pembelajaran yang dapat digunakan untuk meningkatkan kemampuan koneksi matematis diantaranya adalah model pembelajaran REACT dan Learning Cycle 5E. Penelitian ini bertujuan untuk mengetahui terdapat atau tidaknya perbedaan kemampuan koneksi matematis peserta didik yang diajarkan dengan kedua model tersebut. Penelitian dilaksanakan di SMKN 39 Jakarta dengan populasi kelas X semester ganjil tahun pelajaran 2015-2016. Sampel yang diteliti sebanyak 61 orang dengan menggunakan design penelitian quasi experimental. Variabel bebas : model pembelajaran REACT dan model pembelajaran Learning Cycle 5E. Variabel terikat : kemampuan koneksi matematis. Uji instrumen dengan uji validitas dan uji reliabilitas. Uji validitas dengan rumus korelasi Product Moment didapat 7 soal yang valid. Uji reliabilitas dengan rumus Alpha menunjukan bahwa soal tersebut reliabel. Uji normalitas dengan uji Lilliefors menunjukan kedua sampel dari populasi yang berdistribusi normal. Uji homogenitas dengan uji Fisher menunjukan kedua sampel memiliki varians yang homogen. Uji hipotesis dengan uji-t  didapat  dengan alpha sebesar 0,05, maka  di tolak. Dengan demikian terdapat perbedaan kemampuan koneksi matematis peserta didik yang diajarkan dengan model pembelajaran REACT dan model pembelajaran Learning Cycle 5E di SMKN 39 Jakarta.   Kata Kunci: Kemampuan Koneksi Matematis, Model Pembelajaran REACT      Model Pembelajaran Learning Cycle 5E.

Europa Lander Material Selection Considerations

Energy Technology Data Exchange (ETDEWEB)

Tappan, Alexander S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Heller, Mellisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-01-10

Energetic materials (EMs, explosives, pyrotechnics, propellants) provide high-power output of high temperature reaction products. These products can be solid, liquid, or gaseous during reaction or after the products have equilibrated with the surroundings. For example, high explosives typically consist of carbon, hydrogen, nitrogen, and oxygen bonded within a single molecule, and produce almost exclusively gaseous products. Conversely, intermetallics consist of physical mixtures of metals and metalloids, and produce almost exclusively condensed products. Other materials such as pyrotechnics and propellants have intermediate behavior. All energetic materials react in a self-propagating manner that after ignition, does not necessarily require energy input from the surroundings. The range of reaction velocities can range from mm/s for intermetallics, to km/s for high explosives. Energetic material selection depends on numerous requirements specific to the needs of a system. High explosives are used for applications where high pressure gases are necessary for pushing or fracturing materials (e.g., rock, metal) or creating shock waves or air blast. Propellants are used to produce moderate-pressure, high-temperature products without a shock wave. Pyrotechnics are used to produce numerous effects including: high-temperature products, gases, light, smoke, sound, and others. Thermites are used to produce heat, high-temperature products, materials, and other effects that require condensed products. Intermetallics are used to produce high-temperature condensed products and materials, with very little gas production. Numerous categories of energetic materials exist with overlapping definitions, effects, and properties.

Tests of candidate materials for particle bed reactors

International Nuclear Information System (INIS)

Horn, F.L.; Powell, J.R.; Wales, D.

1987-01-01

Rhenium metal hot frits and zirconium carbide-coated fuel particles appear suitable for use in flowing hydrogen to at least 2000 K, based on previous tests. Recent tests on alternate candidate cooled particle and frit materials are described. Silicon carbide-coated particles began to react with rhenium frit material at 1600 K, forming a molten silicide at 2000 K. Silicon carbide was extensively attacked by hydrogen at 2066 K for 30 minutes, losing 3.25% of its weight. Vitrous carbon was also rapidly attacked by hydrogen at 2123 K, losing 10% of its weight in two minutes. Long term material tests on candidate materials for closed cycle helium cooled particle bed fuel elements are also described. Surface imperfections were found on the surface of pyrocarbon-coated fuel particles after ninety days exposure to flowing (∼500 ppM) impure helium at 1143 K. The imperfections were superficial and did not affect particle strength

Optimal stretching in the reacting wake of a bluff body.

Science.gov (United States)

Wang, Jinge; Tithof, Jeffrey; Nevins, Thomas D; Colón, Rony O; Kelley, Douglas H

2017-12-01

We experimentally study spreading of the Belousov-Zhabotinsky reaction behind a bluff body in a laminar flow. Locations of reacted regions (i.e., regions with high product concentration) correlate with a moderate range of Lagrangian stretching and that range is close to the range of optimal stretching previously observed in topologically different flows [T. D. Nevins and D. H. Kelley, Phys. Rev. Lett. 117, 164502 (2016)]. The previous work found optimal stretching in a closed, vortex dominated flow, but this article uses an open flow and only a small area of appreciable vorticity. We hypothesize that optimal stretching is common in advection-reaction-diffusion systems with an excitation threshold, including excitable and bistable systems, and that the optimal range depends on reaction chemistry and not on flow shape or characteristic speed. Our results may also give insight into plankton blooms behind islands in ocean currents.

Surface Modification Technique of Cathode Materials for LI-ION Battery

Science.gov (United States)

Jia, Yongzhong; Han, Jinduo; Jing, Yan; Jin, Shan; Qi, Taiyuan

Cathode materials for Li-ion battery LiMn2O4 and LiCo0.1Mn1.9O4 were prepared by soft chemical method. Carbon, which was made by decomposing organic compounds, was used as modifying agent. Cathode material matrix was mixed with water solution that had contained organic compound such as cane sugar, soluble amylum, levulose et al. These mixture were reacted at 150 200 °C for 0.5 4 h in a Teflon-lined autoclave to get a series of homogeneously C-coated cathode materials. The new products were analyzed by X-ray diffraction (XRD) and infrared (IR). Morphology of cathode materials was characterized by scanning electron microscope (SEM) and transition electron microscope (TEM). The new homogeneously C-coated products that were used as cathode materials of lithium-ion battery had good electrochemical stability and cycle performance. This technique has free-pollution, low cost, simpleness and easiness to realize the industrialization of the cathode materials for Li-ion battery.

Simulation of moving boundaries interacting with compressible reacting flows using a second-order adaptive Cartesian cut-cell method

Science.gov (United States)

Muralidharan, Balaji; Menon, Suresh

2018-03-01

A high-order adaptive Cartesian cut-cell method, developed in the past by the authors [1] for simulation of compressible viscous flow over static embedded boundaries, is now extended for reacting flow simulations over moving interfaces. The main difficulty related to simulation of moving boundary problems using immersed boundary techniques is the loss of conservation of mass, momentum and energy during the transition of numerical grid cells from solid to fluid and vice versa. Gas phase reactions near solid boundaries can produce huge source terms to the governing equations, which if not properly treated for moving boundaries, can result in inaccuracies in numerical predictions. The small cell clustering algorithm proposed in our previous work is now extended to handle moving boundaries enforcing strict conservation. In addition, the cell clustering algorithm also preserves the smoothness of solution near moving surfaces. A second order Runge-Kutta scheme where the boundaries are allowed to change during the sub-time steps is employed. This scheme improves the time accuracy of the calculations when the body motion is driven by hydrodynamic forces. Simple one dimensional reacting and non-reacting studies of moving piston are first performed in order to demonstrate the accuracy of the proposed method. Results are then reported for flow past moving cylinders at subsonic and supersonic velocities in a viscous compressible flow and are compared with theoretical and previously available experimental data. The ability of the scheme to handle deforming boundaries and interaction of hydrodynamic forces with rigid body motion is demonstrated using different test cases. Finally, the method is applied to investigate the detonation initiation and stabilization mechanisms on a cylinder and a sphere, when they are launched into a detonable mixture. The effect of the filling pressure on the detonation stabilization mechanisms over a hyper-velocity sphere launched into a hydrogen

Partial oxidation process

International Nuclear Information System (INIS)

Najjar, M.S.

1987-01-01

A process is described for the production of gaseous mixtures comprising H/sub 2/+CO by the partial oxidation of a fuel feedstock comprising a heavy liquid hydrocarbonaceous fuel having a nickel, iron, and vanadium-containing ash or petroleum coke having a nickel, iron, and vanadium-containing ash, or mixtures thereof. The feedstock includes a minimum of 0.5 wt. % of sulfur and the ash includes a minimum of 5.0 wt. % vanadium, a minimum of 0.5 ppm nickel, and a minimum of 0.5 ppm iron. The process comprises: (1) mixing together a copper-containing additive with the fuel feedstock; wherein the weight ratio of copper-containing additive to ash in the fuel feedstock is in the range of about 1.0-10.0, and there is at least 10 parts by weight of copper for each part by weight of vanadium; (2) reacting the mixture from (1) at a temperature in the range of 2200 0 F to 2900 0 F and a pressure in the range of about 5 to 250 atmospheres in a free-flow refactory lined partial oxidation reaction zone with a free-oxygen containing gas in the presence of a temperature moderator and in a reducing atmosphere to produce a hot raw effluent gas stream comprising H/sub 2/+CO and entrained molten slag; and where in the reaction zone and the copper-containing additive combines with at least a portion of the nickel and iron constituents and sulfur found in the feedstock to produce a liquid phase washing agent that collects and transports at least a portion of the vanadium-containing oxide laths and spinels and other ash components and refractory out of the reaction zone; and (3) separating nongaseous materials from the hot raw effluent gas stream

Effects of ionizing radiation on food packaging materials and quality

International Nuclear Information System (INIS)

Welle, F.; Franz, R.

1999-01-01

Tests have shown that ionizing radiation induces a characteristic smell in the packaging laminates which also affects the simulated foods used, which however were relatively neutral in flavour, so that the tests represent the worst case. The paper explains that due to the various additives used in the production of the plastic packaging materials, the same types of polymers may react differently to the ionizing radiation, so that the results obtained from the tests are not suitable for general application. It is recommended to very carefully select the suitable packaging material for given foods and intended irradiation processes. Aspects of particular importance are discusses. (orig./CB) [de

Thermal effects on transducer material for heat assisted magnetic recording application

Energy Technology Data Exchange (ETDEWEB)

Ji, Rong, E-mail: Ji-Rong@dsi.a-star.edu.sg; Xu, Baoxi; Cen, Zhanhong; Ying, Ji Feng; Toh, Yeow Teck [Data Storage Institute, Agency for Science, Technology and Research (A-STAR), 5 Engineering Drive 1, Singapore 117608 (Singapore)

2015-05-07

Heat Assisted Magnetic Recording (HAMR) is a promising technology for next generation hard disk drives with significantly increased data recording capacities. In HAMR, an optical near-field transducer (NFT) is used to concentrate laser energy on a magnetic recording medium to fulfill the heat assist function. The key components of a NFT are transducer material, cladding material, and adhesion material between the cladding and the transducer materials. Since transducer materials and cladding materials have been widely reported, this paper focuses on the adhesion materials between the Au transducer and the Al{sub 2}O{sub 3} cladding material. A comparative study for two kinds of adhesion material, Ta and Cr, has been conducted. We found that Ta provides better thermal stability to the whole transducer than Cr. This is because after thermal annealing, chromium forms oxide material at interfaces and chromium atoms diffuse remarkably into the Au layer and react with Au to form Au alloy. This study also provides insights on the selection of adhesion material for HAMR transducer.

Lithium mass transport in ceramic breeder materials

International Nuclear Information System (INIS)

Blackburn, P.E.; Johnson, C.E.

1990-01-01

The objective of this activity is to measure the lithium vaporization from lithium oxide breeder material under differing temperature and moisture partial pressure conditions. Lithium ceramics are being investigated for use as tritium breeding materials. The lithium is readily converted to tritium after reacting with a neutron. With the addition of 1000 ppM H 2 to the He purge gas, the bred tritium is readily recovered from the blanket as HT and HTO above 400 degree C. Within the solid, tritium may also be found as LiOT which may transport lithium to cooler parts of the blanket. The pressure of LiOT(g), HTO(g), or T 2 O(g) above Li 2 O(s) is the same as that for reactions involving hydrogen. In our experiments we were limited to the use of hydrogen. The purpose of this work is to investigate the transport of LiOH(g) from the blanket material. 8 refs., 1 fig., 3 tabs

Computational Screening for Design of Optimal Coating Materials to Suppress Gas Evolution in Li-Ion Battery Cathodes.

Science.gov (United States)

Min, Kyoungmin; Seo, Seung-Woo; Choi, Byungjin; Park, Kwangjin; Cho, Eunseog

2017-05-31

Ni-rich layered oxides are attractive materials owing to their potentially high capacity for cathode applications. However, when used as cathodes in Li-ion batteries, they contain a large amount of Li residues, which degrade the electrochemical properties because they are the source of gas generation inside the battery. Here, we propose a computational approach to designing optimal coating materials that prevent gas evolution by removing residual Li from the surface of the battery cathode. To discover promising coating materials, the reactions of 16 metal phosphates (MPs) and 45 metal oxides (MOs) with the Li residues, LiOH, and Li 2 CO 3 are examined within a thermodynamic framework. A materials database is constructed according to density functional theory using a hybrid functional, and the reaction products are obtained according to the phases in thermodynamic equilibrium in the phase diagram. In addition, the gravimetric efficiency is calculated to identify coating materials that can eliminate Li residues with a minimal weight of the coating material. Overall, more MP and MO materials react with LiOH than with Li 2 CO 3 . Specifically, MPs exhibit better reactivity to both Li residues, whereas MOs react more with LiOH. The reaction products, such as Li-containing phosphates or oxides, are also obtained to identify the phases on the surface of a cathode after coating. On the basis of the Pareto-front analysis, P 2 O 5 could be an optimal material for the reaction with both Li residuals. Finally, the reactivity of the coating materials containing 3d/4d transition metal elements is better than that of materials containing other types of elements.

Possible effects of small-scale intermittency in turbulent reacting flows

International Nuclear Information System (INIS)

Sreenivasan, K.R.

2006-12-01

It is now well established that quantities such as energy dissipation, scalar dissipation and enstrophy possess huge fluctuations in turbulent flows, and that the fluctuations become increasingly stronger with increasing Reynolds number of the flow. The effects of this small-scale 'intermittency' on various aspects of reacting flows have not been addressed fully. This paper draws brief attention to a few possible effects on reaction rates, flame extinction, flamelet approximation, conditional moment closure methods, and so forth, besides commenting on possible effects on the resolution requirements of direct numerical simulations of turbulence. We also discuss the likelihood that large-amplitude events in a given class of shear flows are characteristic of that class, and that, plausible estimates of such quantities cannot be made, in general, on the hypothesis that large and small scales are independent. Finally, we briefly describe some ideas from multifractals as a potentially useful tool for an economical handling of a few of the problems touched upon here. (author)

Wildfire simulation using a chemically-reacting plume in a crossflow

Science.gov (United States)

Breidenthal, Robert; Alvarado, Travis; Potter, Brian

2010-11-01

Water tunnel experiments reveal the flame length of a chemically-reacting plume in a crossflow. Salt water containing a pH indicator and a base is slowly injected from above into the test section of a water tunnel containing an acidic solution. The flame length is measured optically as a function of the buoyancy flux, crossflow speed, and volume equivalence ratio of the chemical reaction. Based on earlier work of Broadwell with the transverse jet, a simple dilution model predicts the flame length of the transverse plume. The plume observations are in accord with the model. As with the jet, there is a minimum in the flame length of the plume at a transition between two self-similar regimes, corresponding to the formation of a pair of counter-rotating vortices at a certain crossflow speed. At the transition, there is a maximum in the entrainment and mixing rates. In an actual wildfire with variable winds, this transition may correspond to a dangerous condition for firefighters.

CERN reacts to increased costs to completion of the LHC

CERN Multimedia

2002-01-01

Aspects of LHC construction. The CERN Council, where the representatives of the 20 Member States of the Organization decide on scientific programmes and financial resources, held its 120th session on 14 December under the chairmanship of Prof. Maurice Bourquin (CH). CERN adjusts to the LHC Director-General, Luciano Maiani, stressed that CERN was now fully engaged in the LHC and outlined the first moves to react to the increased cost to completion of the LHC. The new accelerator is an extremely complex, high-tech project which CERN is building under very severe conditions. However, the technical challenges are solved and industrial production of accelerator elements, and installation are starting. Professor Maiani said that 2001 had been a very hard but decisive year for CERN. An important milestone had been passed during this meeting with the approval of the LHC dipole magnets contract, the last major contract for the accelerator. The new costs to completion of the LHC project are now clear. A first propos...

Fixation by ion exchange of toxic materials in a glass matrix

International Nuclear Information System (INIS)

Litovitz, T.A.; Simmons, C.J.; Simmons, J.H.; Macedo, P.B.

1981-01-01

A process for disposing of toxic materials such as radioactive waste comprises reacting a porous silicate glass or silica gel, having interconnected pores and alkali metal cations. Group 1b metal cations and/or ammonium cation bonded to silicon through divalent oxygen linkages on the internal surfaces of said pores, with a toxic material containing toxic cations as well as non-cationic portions. The toxic cations are capable of displacing the alkali metal cations, Group 1b metal cations and/or ammonium cations to provide a distribution of internal silicon-bonded toxic cation oxide groups within the pores of the glass or silica gel. (author)

Nonlinear Stability and Structure of Compressible Reacting Mixing Layers

Science.gov (United States)

Day, M. J.; Mansour, N. N.; Reynolds, W. C.

2000-01-01

The parabolized stability equations (PSE) are used to investigate issues of nonlinear flow development and mixing in compressible reacting shear layers. Particular interest is placed on investigating the change in flow structure that occurs when compressibility and heat release are added to the flow. These conditions allow the 'outer' instability modes- one associated with each of the fast and slow streams-to dominate over the 'central', Kelvin-Helmholtz mode that unaccompanied in incompressible nonreacting mixing layers. Analysis of scalar probability density functions in flows with dominant outer modes demonstrates the ineffective, one-sided nature of mixing that accompany these flow structures. Colayer conditions, where two modes have equal growth rate and the mixing layer is formed by two sets of vortices, offer some opportunity for mixing enhancement. Their extent, however, is found to be limited in the mixing layer's parameter space. Extensive validation of the PSE technique also provides a unique perspective on central- mode vortex pairing, further supporting the view that pairing is primarily governed perspective sheds insight on how linear stability theory is able to provide such an accurate prediction of experimentally-observed, fully nonlinear flow phenomenon.

Flexible Composite-Material Pressure Vessel

Science.gov (United States)

Brown, Glen; Haggard, Roy; Harris, Paul A.

2003-01-01

A proposed lightweight pressure vessel would be made of a composite of high-tenacity continuous fibers and a flexible matrix material. The flexibility of this pressure vessel would render it (1) compactly stowable for transport and (2) more able to withstand impacts, relative to lightweight pressure vessels made of rigid composite materials. The vessel would be designed as a structural shell wherein the fibers would be predominantly bias-oriented, the orientations being optimized to make the fibers bear the tensile loads in the structure. Such efficient use of tension-bearing fibers would minimize or eliminate the need for stitching and fill (weft) fibers for strength. The vessel could be fabricated by techniques adapted from filament winding of prior composite-material vessels, perhaps in conjunction with the use of dry film adhesives. In addition to the high-bias main-body substructure described above, the vessel would include a low-bias end substructure to complete coverage and react peak loads. Axial elements would be overlaid to contain damage and to control fiber orientation around side openings. Fiber ring structures would be used as interfaces for connection to ancillary hardware.

Advances in Materials for Recent Low-Profile Implantable Bioelectronics

Directory of Open Access Journals (Sweden)

Yanfei Chen

2018-03-01

Full Text Available The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material’s property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities.

Advances in Materials for Recent Low-Profile Implantable Bioelectronics

Science.gov (United States)

Kim, Yun-Soung; Tillman, Bryan W.; Chun, Youngjae

2018-01-01

The rapid development of micro/nanofabrication technologies to engineer a variety of materials has enabled new types of bioelectronics for health monitoring and disease diagnostics. In this review, we summarize widely used electronic materials in recent low-profile implantable systems, including traditional metals and semiconductors, soft polymers, biodegradable metals, and organic materials. Silicon-based compounds have represented the traditional materials in medical devices, due to the fully established fabrication processes. Examples include miniaturized sensors for monitoring intraocular pressure and blood pressure, which are designed in an ultra-thin diaphragm to react with the applied pressure. These sensors are integrated into rigid circuits and multiple modules; this brings challenges regarding the fundamental material’s property mismatch with the targeted human tissues, which are intrinsically soft. Therefore, many polymeric materials have been investigated for hybrid integration with well-characterized functional materials such as silicon membranes and metal interconnects, which enable soft implantable bioelectronics. The most recent trend in implantable systems uses transient materials that naturally dissolve in body fluid after a programmed lifetime. Such biodegradable metallic materials are advantageous in the design of electronics due to their proven electrical properties. Collectively, this review delivers the development history of materials in implantable devices, while introducing new bioelectronics based on bioresorbable materials with multiple functionalities. PMID:29596359

Synthesis of hydrogen-carbon clathrate material and hydrogen evolution therefrom at moderate temperatures and pressures

Science.gov (United States)

Lueking, Angela [State College, PA; Narayanan, Deepa [Redmond, WA

2011-03-08

A process for making a hydrogenated carbon material is provided which includes forming a mixture of a carbon source, particularly a carbonaceous material, and a hydrogen source. The mixture is reacted under reaction conditions such that hydrogen is generated and/or released from the hydrogen source, an amorphous diamond-like carbon is formed, and at least a portion of the generated and/or released hydrogen associates with the amorphous diamond-like carbon, thereby forming a hydrogenated carbon material. A hydrogenated carbon material including a hydrogen carbon clathrate is characterized by evolution of molecular hydrogen at room temperature at atmospheric pressure in particular embodiments of methods and compositions according to the present invention.

How Did the Asian Stock Markets React to Bank Mergera after the 1997 Financial Crisis?

OpenAIRE

Meslier-Crouzille , Céline; Lepetit , Laetitia; Bautista , Carlos C.

2008-01-01

International audience; The objective of this paper is to empirically assess the stock market reaction to the announcement of bank mergers and acquisitions (M&As) in eight East Asian countries over the 1997-2003 period. M&As are classified according to the status of entity, the time period of the deal and the maturity of the banking system. A bivariate GARCH model is used to estimate abnormal returns taking beta conditional variability into account. We find that the market reacted negatively ...

Sound attenuation and absorption by anisotropic fibrous materials: Theoretical and experimental study

Science.gov (United States)

Bravo, Teresa; Maury, Cédric

2018-03-01

This paper describes analytical and experimental studies carried out to examine the attenuation and absorption properties of rigidly-backed fibrous anisotropic materials in contact with a uniform mean flow. The aim is to provide insights for the development of non-locally reacting wall-treatments able to dissipate the noise induced by acoustic excitations over in-duct or external lining systems. A model of sound propagation in anisotropic bulk-reacting liners is presented that fully accounts for anisotropic losses due to heat conduction, viscous dissipation and diffusion processes along and across the material fibres as well as for the convective effect of an external flow. The propagation constant for the least attenuated mode of the coupled system is obtained using a simulated annealing search method. The predicted acoustical performance is validated in the no-flow case for a wide range of fibre diameters. They are assessed against impedance tube and free-field pressure-velocity measurements of the normal incidence absorption coefficient and surface impedance. Parametric studies are then conducted to determine the key constitutive parameters such as the fibres orientation or the amount of anisotropy that mostly influence the axial attenuation or the normal absorption. They are supported by a low-frequency approximation to the axial attenuation under a low-speed flow.

In situ X-ray diffraction characterisation of Fe0.5TiOPO4 and Cu0.5TiOPO4 as electrode material for sodium-ion batteries

International Nuclear Information System (INIS)

Bleith, Peter; Kaiser, Hermann; Novák, Petr; Villevieille, Claire

2015-01-01

Na-ion batteries might become a low-cost alternative to Li-ion batteries in the future. Suitable electrode materials, especially anode materials, are needed for Na-ion batteries. As possible candidates Cu 0.5 TiOPO 4 and Fe 0.5 TiOPO 4 were tested. While Cu 0.5 TiOPO 4 does not react with Na + , Fe 0.5 TiOPO 4 shows a specific charge of ≈600 mAh/g upon the first sodiation and 280 mAh/g in the first desodiation. In situ XRD in a new, versatile and reliable in situ cell revealed that Fe 0.5 TiOPO 4 reacts via a conversion type reaction upon sodiation with an amorphisation of the sample

Design Modifications, Fabrication and Test of HFDB-03 Racetrack Magnet Wound with Pre-Reacted Nb3Sn Rutherford Cable

International Nuclear Information System (INIS)

Ambrosio, G.; Andreev, N.; Barzi, E.; Bhashyam, S.; Carcagno, R.; Feher, S.; Imbasciati, L.; Lamm, M.; Pischalnikov, Y.; Tartaglia, M.; Tompkins, J.; Zlobin, A.V.

2004-01-01

A 10 T racetrack magnet (HFDB-03) wound with pre-reacted Nb3Sn Rutherford cable has been fabricated and tested at Fermilab. This magnet is the third one in a proof-of-principle series for the use of the React-and-Wind technology in common-coil dipole magnets for future accelerators. It consists of two flat racetrack coils (28 turns each) separated by 5 mm. The maximum field on the coil, at the short sample limit of 16530 A, is 10 tesla. The cable has 41 strands with 0.7 mm diameter and the minimum bend radius in the magnet ends is 90 mm. The predecessor of this magnet (HFDB-02) reached 78 % of the short sample limit at 7.7 T. The mechanical design was improved and the fabrication procedure was slightly modified in order to address possible causes of limitation. In this paper we present the mechanical design and analysis of HFDB-03, the modifications to the fabrication procedure and the test results

Longitudinally Vibrating Elastic Rods with Locally and Non-Locally Reacting Viscous Dampers

Directory of Open Access Journals (Sweden)

Şefaatdin Yüksel

2005-01-01

Full Text Available Eigencharacteristics of a longitudinally vibrating elastic rod with locally and non-locally reacting damping are analyzed. The rod is considered as a continuous system and complex eigenfrequencies are determined as solution of a characteristic equation. The variation of the damping ratios with respect to damper locations and damping coefficients for the first four eigenfrequencies are obtained. It is shown that at any mode of locally or non-locally damped elastic rod, the variation of damping ratio with damper location is linearly proportional to absolute value of the mode shape of undamped system. It is seen that the increasing damping coefficient does not always increase the damping ratio and there are optimal values for the damping ratio. Optimal values for external damping coefficients of viscous dampers and locations of the dampers are presented.

Serum and plasma fibronectin binds to complement reacted immune complexes primarily via Clq

DEFF Research Database (Denmark)

Baatrup, G; Svehag, S E

1986-01-01

The binding of fibronectin to human Clq, C3b, and complement-reacted immune complexes (IC) was investigated by enzyme-linked immunosorbent assays. Microplates were coated with BSA followed by incubation with rabbit-anti-BSA IgG or F(ab')2 fragments of rabbit anti-BSA. Incubation of the solid phase...... with serum at 37 degrees C caused attachment of Clq and C3b. Addition of EDTA to the serum inhibited the binding of C3b, but not Clq, whereas substitution of the anti-BSA IgG on the solid phase with the F(ab')2 fragments abrogated the Clq, but not the C3b binding. Fibronectin binding was observed after...

A Two-Temperature Open-Source CFD Model for Hypersonic Reacting Flows, Part One: Zero-Dimensional Analysis

OpenAIRE

Vincent Casseau; Rodrigo C. Palharini; Thomas J. Scanlon; Richard E. Brown

2016-01-01

A two-temperature CFD (computational fluid dynamics) solver is a prerequisite to any spacecraft re-entry numerical study that aims at producing results with a satisfactory level of accuracy within realistic timescales. In this respect, a new two-temperature CFD solver, hy2Foam, has been developed within the framework of the open-source CFD platform OpenFOAM for the prediction of hypersonic reacting flows. This solver makes the distinct juncture between the trans-rotational and multiple vibrat...

The nature of cometary materials

International Nuclear Information System (INIS)

Stephens, J.

1989-01-01

Because cometary surfaces are likely to be far colder and of a different composition than planetary surfaces, there are some new considerations that must be examined in regards to placing instrumented packages or sample return devices on their surfaces. The qualitative analysis of the problem of attaching hardware to a comet and not being ejected back into space can be divided into two parts. The first problem is to pierce the mantle and obtain access to the icy core. Drilling through the mantle requires that the drilling forces be reacted. Reacting such forces probably requires attachment to the icy core below. Therefore, some kinetic impact piercing device is likely to be required as the first act of attachment. The second problem for a piercing device to overcome is the force produced by the impact kinetic energy that tries to eject the piercing device back into space. The mantle and icy core can absorb some of the impact kinetic energy in the form of fracture formation and friction energy. The energy that is not absorbed in these two ways is stored by the core as elastic deformation of the mantle and icy core. It is concluded that because the cometary materials are almost certainly brittle and the icy core is likely to be self lubricating, the elastic rebound and gas pressure expulsion forces must be counteracted by forces greater than those that may be provided by a piercing device or its capture devices (barbs)

Adsorption and revaporisation studies on iodine oxide aerosols deposited on containment surface materials in LWR

International Nuclear Information System (INIS)

Tietze, S.; Foreman, M.R.StJ.; Ekberg, C.; Kaerkelae, T.; Auvinen, A.; Tapper, U.; Lamminmaeki, S.; Jokiniemi, J.

2012-12-01

During a hypothetical severe nuclear accident, the radiation field will be very high in the nuclear reactor containment building. As a result gaseous radiolysis products will be formed. Elemental iodine can react in the gaseous phase with ozone to form solid iodine oxide aerosol particles (iodine oxide). Within the AIAS (Adsorption of Iodine oxide Aerosols on Surfaces) project the interactions of iodine oxide (IOx) aerosols with common containment surface materials were investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS, as well as Pt and Pd surfaces from hydrogen recombiners. Non-radioactive and 131 I labelled iodine oxide aerosols were produced with the EXSI CONT facility from elemental iodine and ozone at VTT Technical Research Centre of Finland. The iodine oxide deposits were analysed with microscopic and spectroscopic measurement techniques to identify the kind of iodine oxide formed and if a chemical conversion on the different surface materials occurs. The revaporisation behaviour of the deposited iodine oxide aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 having a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The revaporisated 131 I species from the surfaces were chemically tested for elemental iodine formation. The parameter dominating the degradation of the produced iodine oxide aerosols was humidity. Cu and Zn surfaces were found to react with iodine from the iodine oxide aerosols to form iodides, while no metal iodides were detected for Al and SS samples. Most of the iodine oxide aerosols are assumed to be

Improvement of performance of ultra-high performance concrete based composite material added with nano materials

Directory of Open Access Journals (Sweden)

Pang Jinchang

2016-03-01

Full Text Available Ultra-high performance concrete (UHPC, a kind of composite material characterized by ultra high strength, high toughness and high durability. It has a wide application prospect in engineering practice. But there are some defects in concrete. How to improve strength and toughness of UHPC remains to be the target of researchers. To obtain UHPC with better performance, this study introduced nano-SiO2 and nano-CaCO3 into UHPC. Moreover, hydration heat analysis, X-Ray Diffraction (XRD, mercury intrusion porosimetry (MIP and nanoindentation tests were used to explore hydration process and microstructure. Double-doped nanomaterials can further enhance various mechanical performances of materials. Nano-SiO2 can promote early progress of cement hydration due to its high reaction activity and C-S-H gel generates when it reacts with cement hydration product Ca(OH2. Nano-CaCO3 mainly plays the role of crystal nucleus effect and filling effect. Under the combined action of the two, the composite structure is denser, which provides a way to improve the performance of UHPC in practical engineering.

Colorimetric determination of a paracetamole in raw material and in pharmaceutical dosage forms

International Nuclear Information System (INIS)

Usifoh, C.O; Adelusi, S.A.; Adebambo, R.F.

2002-01-01

A rapid, accurate and simple method is proposed for the determination of p-acetaminophen (paracetamole) in raw material, tablets and syrups. The method is based on measuring the intensity of the yellow color that developed when acute acetaminophen is allowed to react with p-dimethylaminobenzaldehyde in 2M HCl after heating. The color which absorbs in the visible region of gamma 450 nm is stable for several hours and the intensity is directly proportional to the concentration of the drug, that is, Beer lambert law is obeyed. The method can be used to analyse paracetamole in raw material and in pharmaceutical dosage forms. (author)

ENVIRONMENT: a computational platform to stochastically simulate reacting and self-reproducing lipid compartments

Science.gov (United States)

Mavelli, Fabio; Ruiz-Mirazo, Kepa

2010-09-01

'ENVIRONMENT' is a computational platform that has been developed in the last few years with the aim to simulate stochastically the dynamics and stability of chemically reacting protocellular systems. Here we present and describe some of its main features, showing how the stochastic kinetics approach can be applied to study the time evolution of reaction networks in heterogeneous conditions, particularly when supramolecular lipid structures (micelles, vesicles, etc) coexist with aqueous domains. These conditions are of special relevance to understand the origins of cellular, self-reproducing compartments, in the context of prebiotic chemistry and evolution. We contrast our simulation results with real lab experiments, with the aim to bring together theoretical and experimental research on protocell and minimal artificial cell systems.

The importance of stress percolation patterns in rocks and other polycrystalline materials.

Science.gov (United States)

Burnley, P C

2013-01-01

A new framework for thinking about the deformation behavior of rocks and other heterogeneous polycrystalline materials is proposed, based on understanding the patterns of stress transmission through these materials. Here, using finite element models, I show that stress percolates through polycrystalline materials that have heterogeneous elastic and plastic properties of the same order as those found in rocks. The pattern of stress percolation is related to the degree of heterogeneity in and statistical distribution of the elastic and plastic properties of the constituent grains in the aggregate. The development of these stress patterns leads directly to shear localization, and their existence provides insight into the formation of rhythmic features such as compositional banding and foliation in rocks that are reacting or dissolving while being deformed. In addition, this framework provides a foundation for understanding and predicting the macroscopic rheology of polycrystalline materials based on single-crystal elastic and plastic mechanical properties.

Nano-porous Material with Spherical or Gyroid Cavities Created by Quantitative Etching of Polydimethylsiloxane in Polystyrene-Polydimethylsiloxane Block Copolymers

DEFF Research Database (Denmark)

Ndoni, Sokol; Vigild, Martin Etchells; Berg, Rolf H.

2003-01-01

A new method for quantitative etching of the poly(dimethylsiloxane) block in polystyrene-poly(dimethylsiloxane) (PS-PDMS) block copolymers is reported. Reacting the block copolymer with anhydrous hydrogen fluoride renders a nanoporous material (NPM) with the remaining glassy PS maintaining...... the original bulk morphology. 1H NMR, mass difference, size exclusion chromatography, and X-ray photoelectron spectroscopy were used to characterize the materials before and after etching. NPMs containing spherical and gyroid cavities were prepared, as ascertained by small-angle X-ray scattering...

Composite materials and bodies including silicon carbide and titanium diboride and methods of forming same

Science.gov (United States)

Lillo, Thomas M.; Chu, Henry S.; Harrison, William M.; Bailey, Derek

2013-01-22

Methods of forming composite materials include coating particles of titanium dioxide with a substance including boron (e.g., boron carbide) and a substance including carbon, and reacting the titanium dioxide with the substance including boron and the substance including carbon to form titanium diboride. The methods may be used to form ceramic composite bodies and materials, such as, for example, a ceramic composite body or material including silicon carbide and titanium diboride. Such bodies and materials may be used as armor bodies and armor materials. Such methods may include forming a green body and sintering the green body to a desirable final density. Green bodies formed in accordance with such methods may include particles comprising titanium dioxide and a coating at least partially covering exterior surfaces thereof, the coating comprising a substance including boron (e.g., boron carbide) and a substance including carbon.

Potential performance improvement using a reacting gas (nitrogin tetroxide) as the working fluid in a closed Brayton cycle

Science.gov (United States)

Stochl, R. J.

1979-01-01

The results of an analysis to estimate the performance that could be obtained by using a chemically reacting gas (nitrogen tetroxide) as the working fluid in a closed Brayton cycle are presented. Compared with data for helium as the working fluid, these results indicate efficiency improvements from 4 to 90 percent, depending on turbine inlet temperature, pressures, and gas residence time in heat transfer equipment.

Recovery of light oil from organic materials

Energy Technology Data Exchange (ETDEWEB)

Schultz, E; Schultz, E L

1927-10-04

To recover a high percentage of light oil from organic materials, such as crude oil, shale, and the like, the raw material, as crude oil, is vaporized in a still. The vapors are passed into a converter constructed of zinc, nickel, and lead, or sherardized steel, and contain lime and zinc chloride or zinc oxide and are agitated by paddles. The gases react under pressure which is maintained therein and gradually increased, as the temperatures in the still and converter are both gradually increased, so that after the gases have been condensed an odorless high grade light oil is produced. A pressure of from 2 to 10 lb per square inch is maintained in the converter by means of an expansion valve of the needle type, which is located in the vapor outlet pipe between the converter and the condenser. In a modified form of apparatus, a dephlegmator is located between the converter and the condenser.

Characterization of the solid, airborne materials created when UF6 reacts with moist air flowing in single-pass mode

International Nuclear Information System (INIS)

Pickrell, P.W.

1985-10-01

A series of experiments has been performed in which UF 6 was released into flowing air in order to characterize the solid particulate material produced under non-static conditions. In two of the experiments, the aerosol was allowed to stagnate in a static chamber after release and examined further but in the other experiments characterization was done only on material collected a few seconds after release. Transmission electron microscopy and mass measurement by cascaded impactor were used to characterize the aerosol particles which were usually single spheroids with little agglomeration in evidence. The goal of the work is to determine the chemistry and physics of the UF 6 -atmospheric moisture reaction under a variety of conditions so that information about resulting species and product morphologies is available for containment and removal (knockdown) studies as well as for dispersion plume modeling and toxicology studies. This report completes the milestone for reporting the information obtained from releases of UF 6 into flowing rather than static air. 26 figs., 3 tabs

Thermally Cross-Linkable Hole Transport Materials for Solution Processed Phosphorescent OLEDs

Science.gov (United States)

Kim, Beom Seok; Kim, Ohyoung; Chin, Byung Doo; Lee, Chil Won

2018-04-01

Materials for unique fabrication of a solution-processed, multi-layered organic light-emitting diode (OLED) were developed. Preparation of a hole transport layer with a thermally cross-linkable chemical structure, which can be processed to form a thin film and then transformed into an insoluble film by using an amine-alcohol condensation reaction with heat treatment, was investigated. Functional groups, such as triplenylamine linked with phenylcarbazole or biphenyl, were employed in the chemical structure of the hole transport layer in order to maintain high triplet energy properties. When phenylcarbazole or biphenyl compounds continuously react with triphenylamine under acid catalysis, a chemically stable thin film material with desirable energy-level properties for a blue OLED could be obtained. The prepared hole transport materials showed excellent surface roughness and thermal stability in comparison with the commercial reference material. On the solution-processed model hole transport layer, we fabricated a device with a blue phosphorescent OLED by using sequential vacuum deposition. The maximum external quantum, 19.3%, was improved by more than 40% over devices with the commercial reference material (11.4%).

Safety (management and technology). Safety of chemical materials; Anzen (manejimento to tekunoroji). Kagaku busshitsu no anzensei

Energy Technology Data Exchange (ETDEWEB)

Yoshida, T. [Hosei Univ., Tokyo (Japan). Faculty of Engineering

1994-08-05

In chemical materials there exist hazardous materials causing health damages, environmental pollution, fires and explosions. The hazard analysis has been noted as a means for preventing accidents due to chemical materials. This means leads to an effective method of recognizing hazard, evaluating the risk, and lowering the degree of hazard to an allowable level. This paper describes a hazard analysis of autoreactive materials, out of chemical materials causing fires and explosions, which may react by theirselves and cause accidents. In particular, an example is introduced in which this hazard analysis method is adapted to an experimental production of the next generation gas generating agent for automobile collision safety air-bags. In this manufacturing process, in kneading and granulating processes where lots of materials are handled, materials are used in a moistened state, thus countermeasures for preventing occurrence of combustion and explosion being taken. 5 refs., 2 figs., 4 tabs.

Investigation of Na-CO2 Reaction with Initial Reaction in Various Reacting Surface

International Nuclear Information System (INIS)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan; Wi, Myung-Hwan

2015-01-01

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO 2 reaction according to various experimental parameter. Unlike SWR, Na-CO 2 reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO 2 reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO 2 gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO 2 interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO 2 brayton cycle energy conversion system for Na-CO 2 heat exchanger. And next parameter is sodium surface area which contact between sodium and CO 2 when CO 2 is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm 2 . Additionally, it has been reported in recent years that CO 2 Flow rate affects reactivity less significantly and CO 2 flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO 2 flow rate. Na-CO 2 reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO 2 . Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a database for the SFR safety analysis and additional experiments are needed

Study of Pellets and Lumps as Raw Materials in Silicon Production from Quartz and Silicon Carbide

Science.gov (United States)

Dal Martello, E.; Tranell, G.; Gaal, S.; Raaness, O. S.; Tang, K.; Arnberg, L.

2011-10-01

The use of high-purity carbon and quartz raw materials reduces the need for comprehensive refining steps after the silicon has been produced carbothermically in the electric reduction furnace. The current work aims at comparing the reaction mechanisms and kinetics occurring in the inner part of the reduction furnace when pellets or lumpy charge is used, as well as the effect of the raw material mix. Laboratory-scale carbothermic reduction experiments have been carried out in an induction furnace. High-purity silicon carbide and two different high-purity hydrothermal quartzes were charged as raw materials at different molar ratios. The charge was in the form of lumps (size, 2-5 mm) or as powder (size, 10-20 μm), mixed and agglomerated as pellets (size, 1-3 mm) and reacted at 2273 K (2000 °C). The thermal properties of the quartzes were measured also by heating a small piece of quartz in CO atmosphere. The investigated quartzes have different reactivity in reducing atmosphere. The carbothermal reduction experiments show differences in the reacted charge between pellets and lumps as charge material. Solid-gas reactions take place from the inside of the pellets porosity, whereas reactions in lumps occur topochemically. Silicon in pellets is produced mainly in the rim zone. Larger volumes of silicon have been found when using lumpy charge. More SiO is produced when using pellets than for lumpy SiO2 for the same molar ratio and heating conditions. The two SiC polytypes used in the carbothermal reduction experiments as carbon reductants presented different reactivity.

Low-temperature deuteron irradiation of differently reacted Nb3Sn superconductors

International Nuclear Information System (INIS)

Maier, P.; Seibt, E.

1978-01-01

Irradiation measurements with 50 MeV deuterons at 18 K and subsequent annealing measurements were performed on Nb 3 Sn single and multifilamentary superconductors at the Helium-Bath Irradiation Facility of the Karlsruhe Cyclotron. The critical current densities jsub(c) of Nb 3 Sn bronze-reacted wire samples at various reaction temperatures (Tsub(R)=650,700,750,800 and 850 0 C) with equal layer thickness were measured for integral deuteron fluxes up to PHIsub(t)=0.7x10 18 cm -2 . After a decrease in jsub(c) of 85% at maximum dose a relatively small annealing effect (4 to 10%) was observed at ambient temperatures. The maximum value of the normalized critical current density, jsub(c)/jsub(c0), at PHIsub(t)approximately=10 17 cm -2 increases with increasing reaction temperature. The difference in volume pinning forces before and after irradiation increases less than linear (approximately√PHIsub(t)) with the irradiation dose. An almost linear dependence between the inverse grain diameter (dsub(K) -1 )) and volume pinning force is obtained both before and after irradiation. (Auth.)

REACT-Mod: a mathematical model for transient calculation of chemical reactions with U-Pu-Np-Tc in the aqueous nitric acid solution

International Nuclear Information System (INIS)

Tachimori, Shoichi; Kitamura, Tatsuaki.

1996-10-01

A computer code REACT-Mod which simulates various chemical reactions in an aqueous nitric acid solution involving uranium, plutonium, neptunium, technetium etc. e.g., redox, radiolytic and disproportionation reactions of 68, was developed based on the kinetics model. The numerical solution method adopted in the code are two, a kinetics model totally based on the rate law of which differential equations are solved by the modified Porsing method, and a two-step model based on both the rate law and equilibrium law. Only the former treats 27 radiolytic reactions. The latter is beneficially used to have a quick and approximate result by economical computation. The present report aims not only to explain the concept, chemical reactions treated and characteristics of the model but also to provide details of the program for users of the REACT-Mod code. (author)

Programmable thermal emissivity structures based on bioinspired self-shape materials

Science.gov (United States)

Athanasopoulos, N.; Siakavellas, N. J.

2015-12-01

Programmable thermal emissivity structures based on the bioinspired self-shape anisotropic materials were developed at macro-scale, and further studied theoretically at smaller scale. We study a novel concept, incorporating materials that are capable of transforming their shape via microstructural rearrangements under temperature stimuli, while avoiding the use of exotic shape memory materials or complex micro-mechanisms. Thus, programmed thermal emissivity behaviour of a surface is achievable. The self-shape structure reacts according to the temperature of the surrounding environment or the radiative heat flux. A surface which incorporates self-shape structures can be designed to quickly absorb radiative heat energy at low temperature levels, but is simultaneously capable of passively controlling its maximum temperature in order to prevent overheating. It resembles a “game” of colours, where two or more materials coexist with different values of thermal emissivity/ absorptivity/ reflectivity. The transformation of the structure conceals or reveals one of the materials, creating a surface with programmable - and therefore, variable- effective thermal emissivity. Variable thermal emissivity surfaces may be developed with a total hemispherical emissivity ratio (ɛEff_H/ɛEff_L) equal to 28.

Use of the nonsteady monotonic heating method for complex determination of thermophysical properties of chemically reacting mixture in the case of non-equilibrium proceeding of the chemical reaction

International Nuclear Information System (INIS)

Serebryanyj, G.Z.

1984-01-01

Theoretical analysis is made for the monotonic heating method as applied for complex determination of thermophysical properties of chemically reacting gases. The possibility is shown of simultaneous determination of frozen and equilibrium heat capacity, frozen and equilibrium heat conduction provided non-equilibrium occuring of the reaction in the wide range of temperatures and pressures. The monotonic heating method can be used for complex determination of thermophysical properties of chemically reacting systems in case of non-equilibrium proceeding of the chemical reaction

Synthesis of microporous material faujasite-type from kaolin waste; Sintese de material microporoso do tipo faujasita a partir de rejeito de caulim

Energy Technology Data Exchange (ETDEWEB)

Hildebrando, E.A.; Valenzuela-Diaz, F.R., E-mail: edemarino@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Dept. de Engenharia Metalurgica e de Materiais. Lab. de Materias-Primas Particuladas e Solidos nao Metalicos; Angelica, R.S. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Geociencias. Fac. de Geologia; Neves, R.F. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Tecnologia. Fac. de Engenharia Quimica

2010-07-01

Zeolite with structure faujasite was synthesized using kaolin waste from kaolin processing industries for paper coating as predominant source of silicon and aluminum; the starting material was characterized by XRF, XRD, DTA/TG, SEM, and products obtained by XRD and SEM. Synthesis in hydrothermal conditions occurred on autoclave and time-temperature effects, as well as the relationship Si/Al were considered. The results show that the methodology developed with the waste of calcined kaolin reacting at 90 deg C for 20 hours in an alkaline medium, in the presence of an additional source of silica was obtained zeolite Y as single phase present in the product. (author)

House dust mite (Der p 10) and crustacean allergic patients may react to food containing Yellow mealworm proteins.

Science.gov (United States)

Verhoeckx, Kitty C M; van Broekhoven, Sarah; den Hartog-Jager, Constance F; Gaspari, Marco; de Jong, Govardus A H; Wichers, Harry J; van Hoffen, Els; Houben, Geert F; Knulst, André C

2014-03-01

Due to the imminent growth of the world population, shortage of protein sources for human consumption will arise in the near future. Alternative and sustainable protein sources (e.g. insects) are being explored for the production of food and feed. In this project, the safety of Yellow mealworms (Tenebrio molitor L.) for human consumption was tested using approaches as advised by the European Food Safety Authority for allergenicity risk assessment. Different Yellow mealworm protein fractions were prepared, characterised, and tested for cross-reactivity using sera from patients with an inhalation or food allergy to biologically related species (House dust mite (HDM) and crustaceans) by immunoblotting and basophil activation. Furthermore, the stability was investigated using an in vitro pepsin digestion test. IgE from HDM- and crustacean allergic patients cross-reacted with Yellow mealworm proteins. This cross-reactivity was functional, as shown by the induction of basophil activation. The major cross-reactive proteins were identified as tropomyosin and arginine kinase, which are well known allergens in arthropods. These proteins were moderately stable in the pepsin stability test. Based on these cross-reactivity studies, there is a realistic possibility that HDM- and crustacean allergic patients may react to food containing Yellow mealworm proteins. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stabilization/Solidification of radioactive molten salt waste by using xSiO2-yAl2O3-zP2O5 material

International Nuclear Information System (INIS)

Hwan-Seo Park; In-Tae Kim; Yong-Zun Cho; Seong-Won Park; Eung-Ho Kim

2008-01-01

Molten salt waste generated from the electro metallurgical process to recover uranium and transuranic elements is considered as one of problematic wastes to be difficult to immobilize into a durable for final disposal. As an alternative, this study suggested a new method performed at molten state, where dechlorination was achieved with a new inorganic material containing SiO 2 , Al 2 O 3 and P 2 O 5 (SAP). The SAP as a reactive material to molten salt was prepared by a conventional sol-gel process. The prepared SAPs were reacted with each metal chloride, LiCl, CsCl, SrCl 2 and CeCl 3 at 650 deg. C for 6 hours and also were reacted with simulated salt waste consisting of 90 wt% LiCl, 6.8 wt% CsCl and 3.2 wt% SrCl 2 at different waste loading. All the reactions were carried out in oxidative atmosphere and metal chlorides were effectively converted into stable products under a reasonable reaction ratio

The chilling effect: how do researchers react to controversy?

Directory of Open Access Journals (Sweden)

Joanna Kempner

2008-11-01

Full Text Available BACKGROUND: Can political controversy have a "chilling effect" on the production of new science? This is a timely concern, given how often American politicians are accused of undermining science for political purposes. Yet little is known about how scientists react to these kinds of controversies. METHODS AND FINDINGS: Drawing on interview (n = 30 and survey data (n = 82, this study examines the reactions of scientists whose National Institutes of Health (NIH-funded grants were implicated in a highly publicized political controversy. Critics charged that these grants were "a waste of taxpayer money." The NIH defended each grant and no funding was rescinded. Nevertheless, this study finds that many of the scientists whose grants were criticized now engage in self-censorship. About half of the sample said that they now remove potentially controversial words from their grant and a quarter reported eliminating entire topics from their research agendas. Four researchers reportedly chose to move into more secure positions entirely, either outside academia or in jobs that guaranteed salaries. About 10% of the group reported that this controversy strengthened their commitment to complete their research and disseminate it widely. CONCLUSIONS: These findings provide evidence that political controversies can shape what scientists choose to study. Debates about the politics of science usually focus on the direct suppression, distortion, and manipulation of scientific results. This study suggests that scholars must also examine how scientists may self-censor in response to political events.

The Chilling Effect: How Do Researchers React to Controversy?

Science.gov (United States)

Kempner, Joanna

2008-01-01

Background Can political controversy have a “chilling effect” on the production of new science? This is a timely concern, given how often American politicians are accused of undermining science for political purposes. Yet little is known about how scientists react to these kinds of controversies. Methods and Findings Drawing on interview (n = 30) and survey data (n = 82), this study examines the reactions of scientists whose National Institutes of Health (NIH)-funded grants were implicated in a highly publicized political controversy. Critics charged that these grants were “a waste of taxpayer money.” The NIH defended each grant and no funding was rescinded. Nevertheless, this study finds that many of the scientists whose grants were criticized now engage in self-censorship. About half of the sample said that they now remove potentially controversial words from their grant and a quarter reported eliminating entire topics from their research agendas. Four researchers reportedly chose to move into more secure positions entirely, either outside academia or in jobs that guaranteed salaries. About 10% of the group reported that this controversy strengthened their commitment to complete their research and disseminate it widely. Conclusions These findings provide evidence that political controversies can shape what scientists choose to study. Debates about the politics of science usually focus on the direct suppression, distortion, and manipulation of scientific results. This study suggests that scholars must also examine how scientists may self-censor in response to political events. PMID:19018657

Self-Healing Superhydrophobic Materials Showing Quick Damage Recovery and Long-Term Durability.

Science.gov (United States)

Wang, Liming; Urata, Chihiro; Sato, Tomoya; England, Matt W; Hozumi, Atsushi

2017-09-26

Superhydrophobic coatings/materials are important for a wide variety of applications, but the majority of these man-made coatings/materials still suffer from poor durability because of their lack of self-healing ability. Here, we report novel superhydrophobic materials which can quickly self-heal from various severe types of damage. In this study, we used poly(dimethylsiloxane) (PDMS) infused with two liquids: trichloropropylsilane, which reacts with ambient moisture to self-assemble into grass-like microfibers (named silicone micro/nanograss) on the surfaces and low-viscosity silicone oil (SO), which remains within the PDMS matrices and acts as a self-healing agent. Because of the silicone micro/nanograss structures on the PDMS surfaces and the effective preserve/protection system of a large quantity of SO within the PDMS matrices, our superhydrophobic materials showed quick superhydrophobic recovery under ambient conditions (within 1-2 h) even after exposure to plasma (24 h), boiling water, chemicals, and outside environments. Such an ability is superior to the best self-healing superhydrophobic coatings/materials reported so far.

Decision-making methodology of optimal shielding materials by using fuzzy linear programming

International Nuclear Information System (INIS)

Kanai, Y.; Miura, T.; Hirao, Y.

2000-01-01

The main purpose of our studies are to select materials and determine the ratio of constituent materials as the first stage of optimum shielding design to suit the individual requirements of nuclear reactors, reprocessing facilities, casks for shipping spent fuel, etc. The parameters of the shield optimization are cost, space, weight and some shielding properties such as activation rates or individual irradiation and cooling time, and total dose rate for neutrons (including secondary gamma ray) and for primary gamma ray. Using conventional two-valued logic (i.e. crisp) approaches, huge combination calculations are needed to identify suitable materials for optimum shielding design. Also, re-computation is required for minor changes, as the approach does not react sensitively to the computation result. Present approach using a fuzzy linear programming method is much of the decision-making toward the satisfying solution might take place in fuzzy environment. And it can quickly and easily provide a guiding principle of optimal selection of shielding materials under the above-mentioned conditions. The possibility or reducing radiation effects by optimizing the ratio of constituent materials is investigated. (author)

Thermal-hydraulic characteristics of reacting zone for TWR bundles based on CFD method

International Nuclear Information System (INIS)

Lu Chuan; Yan Mingyu; Lu Jianchao

2013-01-01

Thermal-hydraulic characteristics of reacting zone for TWR (travelling wave reactor) bundles were analysed by CFD method. The calculation results of 7, 19 and 37 fuel pin bundles show the similar characteristics. The hot coolant seems to congregate into the centre as flowing to the downstream area. The high temperature coolant always distributes in the inner area while the temperature shows distinct gradation in the outer area. The temperature difference is more than 100 ℃ for the bundle whose diameter is about 26 cm. The major temperature gradations mainly locate in the outermost fuel rods of two circles while other circles show much smaller temperature gradients. This conclusion is estimated to be true for more fuel pin bundles such as 217 fuel pin bundles. The fuel assembly structure of the existing TWR design should be optimized in future. (authors)

Computational Investigation of Soot and Radiation in Turbulent Reacting Flows

Science.gov (United States)

Lalit, Harshad

This study delves into computational modeling of soot and infrared radiation for turbulent reacting flows, detailed understanding of both of which is paramount in the design of cleaner engines and pollution control. In the first part of the study, the concept of Stochastic Time and Space Series Analysis (STASS) as a numerical tool to compute time dependent statistics of radiation intensity is introduced for a turbulent premixed flame. In the absence of high fidelity codes for large eddy simulation or direct numerical simulation of turbulent flames, the utility of STASS for radiation imaging of reacting flows to understand the flame structure is assessed by generating images of infrared radiation in spectral bands dominated by radiation from gas phase carbon dioxide and water vapor using an assumed PDF method. The study elucidates the need for time dependent computation of radiation intensity for validation with experiments and the need for accounting for turbulence radiation interactions for correctly predicting radiation intensity and consequently the flame temperature and NOx in a reacting fluid flow. Comparison of single point statistics of infrared radiation intensity with measurements show that STASS can not only predict the flame structure but also estimate the dynamics of thermochemical scalars in the flame with reasonable accuracy. While a time series is used to generate realizations of thermochemical scalars in the first part of the study, in the second part, instantaneous realizations of resolved scale temperature, CO2 and H2O mole fractions and soot volume fractions are extracted from a large eddy simulation (LES) to carry out quantitative imaging of radiation intensity (QIRI) for a turbulent soot generating ethylene diffusion flame. A primary motivation of the study is to establish QIRI as a computational tool for validation of soot models, especially in the absence of conventional flow field and measured scalar data for sooting flames. Realizations of

Performance of coils wound from long lengths of surface-coated, reacted, BSCCO-2212 conductor

Energy Technology Data Exchange (ETDEWEB)

Walker, M.S.; Hazelton, D.W.; Gardner, M.T. [Intermagnetics General Corp., Latham, NY (United States)] [and others

1996-10-01

React-before-wind surface-coated BSCCO-2212 is being established as a relatively low cost HTS conductor for practical applications. Quality tape is presently being manufactured in 450-500m lengths at a cost estimated to be 1/3-1/5 of the industry costs of BSCCO-2223 powder-in-tube tape. Robust, mechanically sound coils for applications ranging from NMR insert magnets to transformer windings are being made from this BSCCO-2212 tape. The coils have performed consistently through test and thermal cycling without degradation and as projected from short sample measurements. A hybrid approach, which uses mainly BSCCO- 2212 augmented by BSCCO-2223 conductor in the high radial field end regions, is expected to halve magnet system costs.

Radioimmunoassay of IgG and IgM rheumatoid factors reacting with human IgG

International Nuclear Information System (INIS)

Carson, D.A.; Lawrance, S.; Catalano, M.A.; Vaughan, J.H.; Abraham, G.

1977-01-01

Although IgG rheumatoid factor may play a central role in the pathogenesis of rheumatoid arthritis, previously there have been no precise methods for its specific measurement in serum and synovial fluid. This paper describes a solid phase radioimmunoassay for the independent quantification of IgM and IgG rheumatoid factor reacting with the Fc fragment of human IgG. As measured by this assay, serum IgG rheumatoid factor levels differed significantly between patients with seropositive and seronegative rheumatoid arthritis and normal control subjects. In addition, several sera and joint fluids from patients with seropositive rheumatoid arthritis, even without vasculitis, were shown by gel chromatography to have acid-dissociable complexes of IgG rheumatoid factor suggestive of IgG-IgG dimer or trimer formation

Materials and fabrication processes for operation in hot hydrogen

International Nuclear Information System (INIS)

Tuffias, R.H.; Duffy, A.J.; Arrieta, V.M.; Abrams, W.M.; Benander, R.E.

1997-01-01

Operation in hot (2500 endash 3000 K) hydrogen severely limits the choice of structural materials. Rhenium is nonreactive with and has low permeability to hydrogen, and has sufficient strength up to 2800 K. Carbon, in the form of graphite or carbon composites, has excellent high temperature strength but reacts with hydrogen to form methane at a rapid rate above 2000 K. The carbides of zirconium, niobium, hafnium, and tantalum are nonreactive with and have low permeability to hydrogen, but they can be reliably fabricated only in the form of coatings. In order to demonstrate the Integrated Solar Upper Stage (ISUS) solar-thermal propulsion concept, rhenium and rhenium-coated graphite were chosen as the structural materials for the receiver-absorber-converter (RAC) component of the ISUS system. Several methods were investigated for fabricating the rhenium parts and coatings, with chemical vapor deposition (CVD) and Ultramet chosen as the most likely process and company for success. The CVD or rhenium and other refractory materials were thus applied to the ISUS program for fabrication of the RAC subsystem. copyright 1997 American Institute of Physics

Adsorption and revaporisation studies on iodine oxide aerosols deposited on containment surface materials in LWR

Energy Technology Data Exchange (ETDEWEB)

Tietze, S.; Foreman, M.R.StJ.; Ekberg, C. [Chalmers Univ. of Technology, Goeteborg (Sweden); Kaerkelae, T.; Auvinen, A.; Tapper, U.; Lamminmaeki, S.; Jokiniemi, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

2012-12-15

During a hypothetical severe nuclear accident, the radiation field will be very high in the nuclear reactor containment building. As a result gaseous radiolysis products will be formed. Elemental iodine can react in the gaseous phase with ozone to form solid iodine oxide aerosol particles (iodine oxide). Within the AIAS (Adsorption of Iodine oxide Aerosols on Surfaces) project the interactions of iodine oxide (IOx) aerosols with common containment surface materials were investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS, as well as Pt and Pd surfaces from hydrogen recombiners. Non-radioactive and {sup 131}I labelled iodine oxide aerosols were produced with the EXSI CONT facility from elemental iodine and ozone at VTT Technical Research Centre of Finland. The iodine oxide deposits were analysed with microscopic and spectroscopic measurement techniques to identify the kind of iodine oxide formed and if a chemical conversion on the different surface materials occurs. The revaporisation behaviour of the deposited iodine oxide aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 having a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The revaporisated {sup 131}I species from the surfaces were chemically tested for elemental iodine formation. The parameter dominating the degradation of the produced iodine oxide aerosols was humidity. Cu and Zn surfaces were found to react with iodine from the iodine oxide aerosols to form iodides, while no metal iodides were detected for Al and SS samples. Most of the iodine oxide aerosols are assumed to

Delayed-type hypersensitivity to fragrance materials in a select North American population.

Science.gov (United States)

Belsito, Donald V; Fowler, Joseph F; Sasseville, Denis; Marks, James G; De Leo, Vincent A; Storrs, Frances J

2006-03-01

% HMPCC, 0.3% for 1.5% HMPCC, and 0.2% for 0.5% HMPCC), and tea tree oil (0.3%) less frequently yielded positive reactions. Men were more likely than women to be allergic to cinnamic aldehyde. Women were more likely than men to be allergic to jasmine absolute. Atopic patients were no more likely to react to fragrance materials than were nonatopic patients. Patients who reacted to jasmine absolute tended to be older than the general population whereas those who reacted to tea tree oil tended to be younger than the general population. There were no other demographic differences between patients who reacted to a given fragrance material and the entire population studied. Testing with fragrance mix and balsam of Peru failed to identify the majority of patients in this study who were found to be sensitized to jasmine absolute, HMPCC, or tea tree oil. HMPCC is an uncommon allergen in the North American population. We recommend testing with 5% HMPCC in petrolatum for those patients suspected of having a fragrance allergy.

Synthesis of microporous material faujasite-type from kaolin waste

International Nuclear Information System (INIS)

Hildebrando, E.A.; Valenzuela-Diaz, F.R.; Angelica, R.S.; Neves, R.F.

2010-01-01

Zeolite with structure faujasite was synthesized using kaolin waste from kaolin processing industries for paper coating as predominant source of silicon and aluminum; the starting material was characterized by XRF, XRD, DTA/TG, SEM, and products obtained by XRD and SEM. Synthesis in hydrothermal conditions occurred on autoclave and time-temperature effects, as well as the relationship Si/Al were considered. The results show that the methodology developed with the waste of calcined kaolin reacting at 90 deg C for 20 hours in an alkaline medium, in the presence of an additional source of silica was obtained zeolite Y as single phase present in the product. (author)

Fast Reacting Nano Composite Energetic Materials: Synthesis and Combustion Characterization

Science.gov (United States)

2015-08-24

nanoenergetic composites finding extensive use in ordnance and industrial applications, because of its high heat of combustion (~32 kJ/g) (S. H. Fischer ...2011. Farley, Cory. "Reactions of Aluminum with Halogen Containing Oxides." Dissertation. Lubbock, TX, May 2013. Gesner, Jeff , Michelle Pantoya, and...characteristics of novel hybrid nanoenergetic formulations." Combustion and Flame 158 (2011): 964- 978. S. H. Fischer , M. C. Grubelich. "Theoretical

Evolution of a chemically reacting plume in a ventilated room

Science.gov (United States)

Conroy, D. T.; Smith, Stefan G. Llewellyn; Caulfield, C. P.

2005-08-01

The dynamics of a second-order chemical reaction in an enclosed space driven by the mixing produced by a turbulent buoyant plume are studied theoretically, numerically and experimentally. An isolated turbulent buoyant plume source is located in an enclosure with a single external opening. Both the source and the opening are located at the bottom of the enclosure. The enclosure is filled with a fluid of a given density with a fixed initial concentration of a chemical. The source supplies a constant volume flux of fluid of different density containing a different chemical of known and constant concentration. These two chemicals undergo a second-order non-reversible reaction, leading to the creation of a third product chemical. For simplicity, we restrict attention to the situation where the reaction process does not affect the density of the fluids involved. Because of the natural constraint of volume conservation, fluid from the enclosure is continually vented. We study the evolution of the various chemical species as they are advected by the developing ventilated filling box process within the room that is driven by the plume dynamics. In particular, we study both the mean and vertical distributions of the chemical species as a function of time within the room. We compare the results of analogue laboratory experiments with theoretical predictions derived from reduced numerical models, and find excellent agreement. Important parameters for the behaviour of the system are associated with the source volume flux and specific momentum flux relative to the source specific buoyancy flux, the ratio of the initial concentrations of the reacting chemical input in the plume and the reacting chemical in the enclosed space, the reaction rate of the chemicals and the aspect ratio of the room. Although the behaviour of the system depends on all these parameters in a non-trivial way, in general the concentration within the room of the chemical input at the isolated source passes

Heterogeneous reactions of dioctahedral smectites in illite-smectite and kaolinite-smectite mixed-layers: applications to clay materials for engineered barriers

International Nuclear Information System (INIS)

Meunier, A.; Proust, D.; Beaufort, D.; Lajudie, A.; Petit, J.-C.

1992-01-01

The clay materials selected for use in the engineered barriers of the French nuclear waste isolation programme are mainly composed of dioctahedral smectite, either bentonite of Wyoming type or kaolinite-smectites most often consist of randomly stacked layers with low and high charges. In the case of the Wyoming-type bentonite, these two differently charged layers do not react in the same way when subjected to hydrothermal alteration. Overall, the low-charge smectite layers react to form high-charge smectite layers + quartz + kaolinite. Then, fixing K ions, the high-charge smectite layers are transformed into illite-smectite mixed-layers (I/S) when the temperature conditions increase. A symmetrical process is observed in natural or experimental hydrothermal conditions when the high-charge smectite layers of I/S minerals react with quartz and/or kaolinite to produce low-charge smectite layers. The chemical properties of the bentonite-engineered barriers clearly depend on the low charge/high charge smectite layer proportion, which is in turn controlled by the temperature-dependent reactions in the vicinity of the waste disposal. Although there are fewer published data on the kaolinite-smectite mixed-layered minerals (K/S), a similar low charge-high charge reaction appears to affect their smectite component. The experimental alteration of K/S leads to the formation of a low-charge beidellite with an increase in the cation-exchange capacity and in the expandability of the clay material. Thus, the properties of the engineered barrier seems to be improved after hydrothermal alteration. (Author)

Decision method for optimal selection of warehouse material handling strategies by production companies

Science.gov (United States)

Dobos, P.; Tamás, P.; Illés, B.

2016-11-01

Adequate establishment and operation of warehouse logistics determines the companies’ competitiveness significantly because it effects greatly the quality and the selling price of the goods that the production companies produce. In order to implement and manage an adequate warehouse system, adequate warehouse position, stock management model, warehouse technology, motivated work force committed to process improvement and material handling strategy are necessary. In practical life, companies have paid small attantion to select the warehouse strategy properly. Although it has a major influence on the production in the case of material warehouse and on smooth costumer service in the case of finished goods warehouse because this can happen with a huge loss in material handling. Due to the dynamically changing production structure, frequent reorganization of warehouse activities is needed, on what the majority of the companies react basically with no reactions. This work presents a simulation test system frames for eligible warehouse material handling strategy selection and also the decision method for selection.

Self-Decontaminating Materials

National Research Council Canada - National Science Library

Wander, Joseph

2002-01-01

.... Whereas exclusion and catalytic reactivity tend to persist in the SDM after they have achieved their protective function, chemically active groups that combine or react with the contaminant will...

Anti-N antibody reacting at 37°C: An unusual occurrence interfering with routine testing: Two interesting cases

Directory of Open Access Journals (Sweden)

Vijay Kumawat

2015-01-01

Full Text Available Most anti-N antibodies are naturally occurring, IgM antibodies, and not active above 25°C and are not clinically significant but IgG anti- N has also been described. Immune anti-N resulting from multiple transfusions does occur & has been implicated as the cause of hemolytic transfusion reactions and mild hemolytic disease of fetus and newborn. Anti- N reacting at room temperature can be a cause for ABO blood group discrepancy

Research on optimizing components of microfine high-performance composite cementitious materials

International Nuclear Information System (INIS)

Hu Shuguang; Guan Xuemao; Ding Qingjun

2002-01-01

The relationship between material components and mechanical properties was studied in terms of composite material principles and orthogonal experimental design. Moreover, the microstructure of microfine high-performance composite cementitious material (MHPCC) paste was investigated by means of scanning electron microscopy (SEM) methods. The results showed that the composite material consisting of blast furnace slag (BFS), gypsum (G 2 ) and expansive agent (EA) could obviously improve the strength of the cementitious material containing 40% fly ash (FA). Although microfine cement (MC) was merely 45% percent of the MHPCC, the compressive strength of MHPCC paste was higher than that of neat MC paste. BFS played an important role in MHPCC. The optimum-added quantity of BFS was 15%. The needle-shaped ettringite obtained from the EA reacting with Ca(OH) 2 forms a three-dimensional network structure, which not only improved the early strength of MHPCC paste but also increased its late strength. The reason was that the network structure, which was similar to a fiber-reinforced composite, was formed in the late period of hydration with the progress of hydration and the deposition of hydration products into the network structure

Sol-gel Process in Preparation of Organic-inorganic Hybrid Materials

Directory of Open Access Journals (Sweden)

Macan, J

2008-07-01

Full Text Available Organic-inorganic hybrid materials are a sort of nanostructured material in which the organic and inorganic phases are mixed at molecular level. The inorganic phase in hybrid materials is formed by the sol-gel process, which consists of reactions of hydrolysis and condensation of metal (usually silicon alkoxides. Flexibility of sol-gel process enables creation of hybrid materials with varying organic and inorganic phases in different ratios, and consequently fine-tuning of their properties. In order to obtain true hybrid materials, contact between the phases should be at molecular level, so phase separation between thermodynamically incompatible organic and inorganic phases has to be prevented. Phase interaction can be improved by formation of hydrogen or covalent bonds between them during preparation of hybrid materials. Covalent bond can be introduced by organically modified silicon alkoxides containing a reactive organic group (substituent capable of reacting with the organic phase. In order to obtain hybrid materials with desired structures, a detailed knowledge of hydrolysis and condensation mechanism is necessary. The choice of catalyst, whether acid or base, has the most significant influence on the structure of the inorganic phase. Other important parameters are alkoxide concentration, water: alkoxide ratio, type of alkoxide groups, solvent used, temperature, purity of chemicals used, etc. Hydrolysis and condensation of organically modified silicon alkoxides are additionally influenced by nature and size of the organic supstituent.

Linear models for sound from supersonic reacting mixing layers

Science.gov (United States)

Chary, P. Shivakanth; Samanta, Arnab

2016-12-01

We perform a linearized reduced-order modeling of the aeroacoustic sound sources in supersonic reacting mixing layers to explore their sensitivities to some of the flow parameters in radiating sound. Specifically, we investigate the role of outer modes as the effective flow compressibility is raised, when some of these are expected to dominate over the traditional Kelvin-Helmholtz (K-H) -type central mode. Although the outer modes are known to be of lesser importance in the near-field mixing, how these radiate to the far-field is uncertain, on which we focus. On keeping the flow compressibility fixed, the outer modes are realized via biasing the respective mean densities of the fast (oxidizer) or slow (fuel) side. Here the mean flows are laminar solutions of two-dimensional compressible boundary layers with an imposed composite (turbulent) spreading rate, which we show to significantly alter the growth of instability waves by saturating them earlier, similar to in nonlinear calculations, achieved here via solving the linear parabolized stability equations. As the flow parameters are varied, instability of the slow modes is shown to be more sensitive to heat release, potentially exceeding equivalent central modes, as these modes yield relatively compact sound sources with lesser spreading of the mixing layer, when compared to the corresponding fast modes. In contrast, the radiated sound seems to be relatively unaffected when the mixture equivalence ratio is varied, except for a lean mixture which is shown to yield a pronounced effect on the slow mode radiation by reducing its modal growth.

Synthesis and luminescence properties of cinnamide based nanohybrid materials containing Eu (II) ions

Science.gov (United States)

Kiran Kumar, A. B. V.; Jayasimhadri, M.; Cha, Hyeongrae; Chen, Kuangcai; Lim, Jae-Min; Lee, Yong-Ill

2011-07-01

In the present work, the cinnamide based organic-inorganic hybrid luminescent materials were prepared by using sol-gel technique, in which both the components are covalently linked via Si-C bonds. The organic precursor N-(3-(triethoxysilyl)propyl)cinnamide (Cn-Si) was synthesized by (3-aminopropyl) triethoxysilane being reacted with cinnamoyal chloride. Finally, novel hybrid materials were prepared successfully through hydrolysis and polycondensation processes between the alkoxide groups of precursors Cn-Si and tetraethylorthosilane (TEOS) in the presence of europium nitrate. We have characterized thoroughly the prepared samples using FT-IR, thermal analysis (TGA/DTA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS) and photoluminescence (PL) spectroscopy. The results indicate that these materials exhibit the excellent thermal stability up to 350 °C. The X-ray diffraction patterns confirmed the amorphous nature of the developed materials. The rare-earth doped hybrid materials have exhibited an intense green emission at 530 nm with CIE chromaticity coordinates (0.4801, 0.4669). Whereas, the un-doped one gives some remarkable blue emission properties under UV excitation.

Ecological performance of construction materials subject to ocean climate change.

Science.gov (United States)

Davis, Kay L; Coleman, Melinda A; Connell, Sean D; Russell, Bayden D; Gillanders, Bronwyn M; Kelaher, Brendan P

2017-10-01

Artificial structures will be increasingly utilized to protect coastal infrastructure from sea-level rise and storms associated with climate change. Although it is well documented that the materials comprising artificial structures influence the composition of organisms that use them as habitat, little is known about how these materials may chemically react with changing seawater conditions, and what effects this will have on associated biota. We investigated the effects of ocean warming, acidification, and type of coastal infrastructure material on algal turfs. Seawater acidification resulted in greater covers of turf, though this effect was counteracted by elevated temperatures. Concrete supported a greater cover of turf than granite or high-density polyethylene (HDPE) under all temperature and pH treatments, with the greatest covers occurring under simulated ocean acidification. Furthermore, photosynthetic efficiency under acidification was greater on concrete substratum compared to all other materials and treatment combinations. These results demonstrate the capacity to maximise ecological benefits whilst still meeting local management objectives when engineering coastal defense structures by selecting materials that are appropriate in an ocean change context. Therefore, mitigation efforts to offset impacts from sea-level rise and storms can also be engineered to alter, or even reduce, the effects of climatic change on biological assemblages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Manufacturing and preliminary tests of a 12 T ''wind and react'' coil

International Nuclear Information System (INIS)

Corte, A. della; Pasotti, G.; Sacchetti, N.; Spadoni, M.; Oliva, A.B.; Penco, R.; Parodi, S.; Valle, N.; Specking, W.

1994-01-01

As already reported ENEA is engaged in the realization of a 12 T wind and react Nb 3 Sn coil, a subsize magnet designed to simulate many technological problems to be faced in NET-ITER magnets. EM-LMI and Ansaldo are the industrial partners in this project. A preliminary winding has been built and successfully tested. This winding has been cut in pieces and carefully inspected to be sure that the impregnation process after the heat treatment works well. No particular flaws have been detected. Then manufacturing of the 12 T magnet has been started and completed in about three months. Heat treatment, impregnation and electrical tests at 300 K have been successfully performed and the magnet is now ready for final tests. In order to obtain the most significant scientific and technological information from this magnet, the original test program (insertion of the coil in the SULTAN facility) has been modified according to a decision of the Fusion Technology Steering Committee (FTSC) of EURATOM. Details of the new test programs are given in the paper

Beam plasma 14 MeV neutron source for fusion materials development

International Nuclear Information System (INIS)

Ravenscroft, D.; Bulmer, D.; Coensgen, F.; Doggett, J.; Molvik, A.; Souza, P.; Summers, L.; Williamson, V.

1991-09-01

The conceptual engineering design and expected performance for a 14 MeV DT neutron source is detailed. The source would provide an intense neutron flux for accelerated testing of fusion reactor materials. The 150-keV neutral beams inject energetic deuterium atoms, that ionize, are trapped, then react with a warm (200 eV), dense tritium target plasma. This produces a neutron source strength of 3.6 x 10 17 n/sec for a neutron power density at the plasma edge of 5--10 MW/m 2 . This is several times the ∼2 MW/m 2 anticipated at the first wall of fusion reactors. This high flux provides accelerated end-of-life tests of 1- to 2-year duration, thus making materials development possible. The modular design of the source and the facilities are described

Laminar or turbulent boundary-layer flows of perfect gases or reacting gas mixtures in chemical equilibrium

Science.gov (United States)

Anderson, E. C.; Lewis, C. H.

1971-01-01

Turbulent boundary layer flows of non-reacting gases are predicted for both interal (nozzle) and external flows. Effects of favorable pressure gradients on two eddy viscosity models were studied in rocket and hypervelocity wind tunnel flows. Nozzle flows of equilibrium air with stagnation temperatures up to 10,000 K were computed. Predictions of equilibrium nitrogen flows through hypervelocity nozzles were compared with experimental data. A slender spherically blunted cone was studied at 70,000 ft altitude and 19,000 ft/sec. in the earth's atmosphere. Comparisons with available experimental data showed good agreement. A computer program was developed and fully documented during this investigation for use by interested individuals.

Melanoma inhibitor of apoptosis protein (ML-IAP) specific cytotoxic T lymphocytes cross-react with an epitope from the auto-antigen SS56

DEFF Research Database (Denmark)

Baek Sørensen, Rikke; Faurschou, Mikkel; Troelsen, Lone

2009-01-01

A large proportion of melanoma patients host a spontaneous T-cell response specifically against ML-IAP-derived peptides. In this study, we describe that some ML-IAP-specific cytotoxic T cells isolated from melanoma patients cross react with an epitope from the auto-antigen SS56. SS56 is a recentl...

Characterization of magnetic material in the mound-building termite Macrotermes gilvus in Southeast Asia

Energy Technology Data Exchange (ETDEWEB)

Esa, Mohammad Faris Mohammad; Hassan, Ibrahim Haji [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor (Malaysia); Rahim, Faszly; Hanifah, Sharina Abu [School of Environmental Scieces and Natural Resources Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Selangor (Malaysia)

2015-09-25

Magnetic material such as magnetite are known as particles that respond to external magnetic field with their ferromagnetic properties as they are believed contribute to in responding to the geomagnetic field. These particles are used by terrestrial animals such as termites for navigation and orientation. Since our earth react as giant magnetic bar, the magnitude of this magnetic field present by intensity and direction (inclination and direction). The magnetic properties and presence of magnetite in termites Macrotermes gilvus, common mound-building termite were tested. M. gilvus termites was tested with a Vibrating Sample Magnetometer VSM to determine the magnetic properties of specimen. The crushed body sample was characterized with X-Ray Diffraction XRD to show the existent of magnetic material (magnetite) in the specimens. Results from VSM indicate that M. gilvus has diamagnetism properties. The characterization by XRD shows the existent of magnetic material in our specimen in low concentration.

Characterization of magnetic material in the mound-building termite Macrotermes gilvus in Southeast Asia

International Nuclear Information System (INIS)

Esa, Mohammad Faris Mohammad; Hassan, Ibrahim Haji; Rahim, Faszly; Hanifah, Sharina Abu

2015-01-01

Magnetic material such as magnetite are known as particles that respond to external magnetic field with their ferromagnetic properties as they are believed contribute to in responding to the geomagnetic field. These particles are used by terrestrial animals such as termites for navigation and orientation. Since our earth react as giant magnetic bar, the magnitude of this magnetic field present by intensity and direction (inclination and direction). The magnetic properties and presence of magnetite in termites Macrotermes gilvus, common mound-building termite were tested. M. gilvus termites was tested with a Vibrating Sample Magnetometer VSM to determine the magnetic properties of specimen. The crushed body sample was characterized with X-Ray Diffraction XRD to show the existent of magnetic material (magnetite) in the specimens. Results from VSM indicate that M. gilvus has diamagnetism properties. The characterization by XRD shows the existent of magnetic material in our specimen in low concentration

Characterization of magnetic material in the mound-building termite Macrotermes gilvus in Southeast Asia

Science.gov (United States)

Esa, Mohammad Faris Mohammad; Rahim, Faszly; Hassan, Ibrahim Haji; Hanifah, Sharina Abu

2015-09-01

Magnetic material such as magnetite are known as particles that respond to external magnetic field with their ferromagnetic properties as they are believed contribute to in responding to the geomagnetic field. These particles are used by terrestrial animals such as termites for navigation and orientation. Since our earth react as giant magnetic bar, the magnitude of this magnetic field present by intensity and direction (inclination and direction). The magnetic properties and presence of magnetite in termites Macrotermes gilvus, common mound-building termite were tested. M. gilvus termites was tested with a Vibrating Sample Magnetometer VSM to determine the magnetic properties of specimen. The crushed body sample was characterized with X-Ray Diffraction XRD to show the existent of magnetic material (magnetite) in the specimens. Results from VSM indicate that M. gilvus has diamagnetism properties. The characterization by XRD shows the existent of magnetic material in our specimen in low concentration.

Composite materials comprising two jonal functions and methods for making the same

Science.gov (United States)

Fareed, Ali Syed; Garnier, John Edward; Schiroky, Gerhard Hans; Kennedy, Christopher Robin; Sonuparlak, Birol

2001-01-01

The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants which may enter the composite body. The getterer materials may be placed into at least a portion of the composite body such that any undesirable oxidant approaching, for example, a fiber reinforcement, would be scavenged by (e.g., reacted with) the getterer. The getterer materials) may form at least one compound which acts as a passivation layer, and/or is able to move by bulk transport (e.g., by viscous flow as a glassy material) to a crack, and sealing the crack, thereby further enhancing the oxidation protection of the composite body. One or more ceramic filler materials which serve as reinforcements may have a plurality of super-imposed coatings thereon, at least one of which coatings may function as or contain an oxidation protection mechanism. Specifically, a coating comprising boron nitride which has been engineered or modified to contain some silicon exhibits improved corrosion resistance, specifically to oxygen and moisture. The coated materials may be useful as reinforcing materials in high performance composites to provide improved mechanical properties such as fracture toughness. The present invention also relates to improved composites which incorporate these materials, and to their methods of manufacture.

A second-order coupled immersed boundary-SAMR construction for chemically reacting flow over a heat-conducting Cartesian grid-conforming solid

KAUST Repository

Kedia, Kushal S.; Safta, Cosmin; Ray, Jaideep; Najm, Habib N.; Ghoniem, Ahmed F.

2014-01-01

In this paper, we present a second-order numerical method for simulations of reacting flow around heat-conducting immersed solid objects. The method is coupled with a block-structured adaptive mesh refinement (SAMR) framework and a low-Mach number operator-split projection algorithm. A "buffer zone" methodology is introduced to impose the solid-fluid boundary conditions such that the solver uses symmetric derivatives and interpolation stencils throughout the interior of the numerical domain; irrespective of whether it describes fluid or solid cells. Solid cells are tracked using a binary marker function. The no-slip velocity boundary condition at the immersed wall is imposed using the staggered mesh. Near the immersed solid boundary, single-sided buffer zones (inside the solid) are created to resolve the species discontinuities, and dual buffer zones (inside and outside the solid) are created to capture the temperature gradient discontinuities. The development discussed in this paper is limited to a two-dimensional Cartesian grid-conforming solid. We validate the code using benchmark simulations documented in the literature. We also demonstrate the overall second-order convergence of our numerical method. To demonstrate its capability, a reacting flow simulation of a methane/air premixed flame stabilized on a channel-confined bluff-body using a detailed chemical kinetics model is discussed. © 2014 Elsevier Inc.

A second-order coupled immersed boundary-SAMR construction for chemically reacting flow over a heat-conducting Cartesian grid-conforming solid

KAUST Repository

Kedia, Kushal S.

2014-09-01

In this paper, we present a second-order numerical method for simulations of reacting flow around heat-conducting immersed solid objects. The method is coupled with a block-structured adaptive mesh refinement (SAMR) framework and a low-Mach number operator-split projection algorithm. A "buffer zone" methodology is introduced to impose the solid-fluid boundary conditions such that the solver uses symmetric derivatives and interpolation stencils throughout the interior of the numerical domain; irrespective of whether it describes fluid or solid cells. Solid cells are tracked using a binary marker function. The no-slip velocity boundary condition at the immersed wall is imposed using the staggered mesh. Near the immersed solid boundary, single-sided buffer zones (inside the solid) are created to resolve the species discontinuities, and dual buffer zones (inside and outside the solid) are created to capture the temperature gradient discontinuities. The development discussed in this paper is limited to a two-dimensional Cartesian grid-conforming solid. We validate the code using benchmark simulations documented in the literature. We also demonstrate the overall second-order convergence of our numerical method. To demonstrate its capability, a reacting flow simulation of a methane/air premixed flame stabilized on a channel-confined bluff-body using a detailed chemical kinetics model is discussed. © 2014 Elsevier Inc.

Monoclonal antibodies (MAb) made against insect-derived metacyclic trypomastigotes (IMT) of Trypanosoma cruzi (TC) cross-react with other parasite forms

International Nuclear Information System (INIS)

Kirchhoff, L.V.; Gilliam, F.C.

1986-01-01

Considerable information has been generated in recent years about stage-specific surface membrane antigens of a number of protozoa, and this phenomenon has been observed among several stages of TC as well. However, little is known about the surface antigens of IMT, the true infective stage of TC, because of the difficulty of obtaining sufficient numbers of these organisms for analysis. The Tulahuen strain of TC was maintained in the reduviid vector Dipetalogaster maximus by repeated feeding on mice with high parasitemias. IMT collected with insect urine were irradiated (150 krad) and used to immunize a BALB/c mouse for hybridoma production. Supernatants were screened by immunofluorescence assay for the presence of IgG MAb that react with methanol-fixed IMT, epimastogotes (EPI) and culture-derived metacyclic trypomastigoes (CMT). Of 41 MAb obtained, 40 reacted with IMT, 37 with EPI and 38 with CMT. Four MAb immunoprecipitated radioiodinated proteins or protein conjugates of M/sub r/ 80, 72, 45 and 45 from lysates of 125 I surface-labeled EPI. These results indicate that, at least at the epitopic level, there is considerable overlap among IMT, EPI and CMT surface antigens. This finding suggests that analysis of surface proteins of the latter 2 parasite forms may lead to identification of molecules useful for vaccine development

Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

Science.gov (United States)

Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher; Dai, Sheng

2016-06-07

An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.

Investigation of Na-CO{sub 2} Reaction with Initial Reaction in Various Reacting Surface

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan [POSTECH, Pohang (Korea, Republic of); Wi, Myung-Hwan [KAERI, Daejeon (Korea, Republic of)

2015-10-15

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO{sub 2} reaction according to various experimental parameter. Unlike SWR, Na-CO{sub 2} reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO{sub 2} reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO{sub 2} gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO{sub 2} interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO{sub 2} brayton cycle energy conversion system for Na-CO{sub 2} heat exchanger. And next parameter is sodium surface area which contact between sodium and CO{sub 2} when CO{sub 2} is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm{sup 2}. Additionally, it has been reported in recent years that CO{sub 2} Flow rate affects reactivity less significantly and CO{sub 2} flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO{sub 2} flow rate. Na-CO{sub 2} reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO{sub 2}. Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a

Systems and methods for solar cells with CIS and CIGS films made by reacting evaporated copper chlorides with selenium

Science.gov (United States)

Albin, David S.; Noufi, Rommel

2015-06-09

Systems and methods for solar cells with CIS and CIGS films made by reacting evaporated copper chlorides with selenium are provided. In one embodiment, a method for fabricating a thin film device comprises: providing a semiconductor film comprising indium (In) and selenium (Se) upon a substrate; heating the substrate and the semiconductor film to a desired temperature; and performing a mass transport through vapor transport of a copper chloride vapor and se vapor to the semiconductor film within a reaction chamber.

2, 3-Dihydrazone cellulose: Prospective material for tissue engineering scaffolds

International Nuclear Information System (INIS)

Verma, Vipin; Verma, Poonam; Ray, Pratima; Ray, Alok R.

2008-01-01

Cellulose was oxidized by sodium metaperiodate to give rise to 2, 3-dialdehyde cellulose with 92% oxidation ratio, which was further reacted with hydrazine to form 2, 3-dihydrazone cellulose for the incorporation of NH 2 groups. Two forms of matrix, i.e. films and sponges were fabricated. The materials were characterized by FTIR spectroscopy. Scanning electron microscopy revealed its porous architecture with an average pore size of 150 μm. Swelling studies were carried out in phosphate buffer saline (PBS) at physiological pH 7.4. The contact angle of the 2, 3-dihydrazone cellulose surface was determined for assessing its hydrophilicity which came out to be 23 deg. ± 2 deg. NIH3T3 mice fibroblast cells were used for determining the cytocompatibility of the surfaces. The morphology of the cells was observed through optical inverted microscopy. The results show that 2, 3-dihydrazone cellulose can be used as scaffold material in tissue engineering

Advantage of fast reacting adsorbents like humic acids for the recovery of uranium from seawater

International Nuclear Information System (INIS)

Denzinger, H.; Schnell, C.; Heitkamp, D.; Wagener, K.

1980-01-01

This report is divided into two sections. The first part comprises experimental data of humic acid adsorbers; whereas, the second concerns design parameter and costs of a recovery plant using fast reacting adsorbents. Summarizing the experimental results, hydrogen-loaded humic acids on carriers show an exceptionally fast kinetics of uranium fixation in seawater which is practically temperature independent. This fast adsorption performance may be maintained in a technical recovery process if care is taken to minimize slow diffraction controlled steps preceding the uranium fixation reaction. When humic acid was used instead of titanium hydroxide in the recovery plant, there was a decrease of investment and production costs of about 50%. However, there was a higher percentage of energy costs, i.e., electric power consumption and investments for pumps

Role of the reacting free radicals on the antioxidant mechanism of curcumin

Energy Technology Data Exchange (ETDEWEB)

Galano, Annia, E-mail: agalano@prodigy.net.mx [Universidad Autonoma Metropolitana-Iztapalapa, Departamento de Quimica, Area de Quimica Analitica, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, C.P. 09340, Mexico D.F. (Mexico); Alvarez-Diduk, Ruslan; Ramirez-Silva, Maria Teresa; Alarcon-Angeles, Georgina; Rojas-Hernandez, Alberto [Universidad Autonoma Metropolitana-Iztapalapa, Departamento de Quimica, Area de Quimica Analitica, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, C.P. 09340, Mexico D.F. (Mexico)

2009-09-18

Density functional theory is used to study the antioxidant mechanism of curcumin. Five different mechanisms are considered: single electron transfer (SET), radical adduct formation (RAF), H atom transfer from neutral curcumin (HAT), H atom transfer from deprotonated curcumin (HAT-D), and sequential proton loss electron transfer (SPLET). The influence of the environment is investigated for polar and non-polar surroundings. The apparent contradictions among previous experimental results are explained by the role of the nature of the reacting free radical on the relative importance of the above mentioned mechanism. It is proposed that the curcumin + DPPH reaction actually takes place mainly through the SPLET mechanism, while the reaction with {sup {center_dot}}OCH{sub 3}, and likely with other alkoxyl radicals, is governed by the HAT mechanism. Branching ratios for the {sup {center_dot}}OCH{sub 3} + curcumin reaction are reported for the first time. The calculated overall rate constants for this reaction are 1.16 x 10{sup 10} (benzene) and 5.52 x 10{sup 9} (water) L mol{sup -1} s{sup -1}. The role of phenolic groups on the antioxidant activity of curcumin has been experimentally confirmed.

Building up an electrocatalytic activity scale of cathode materials for organic halide reductions

International Nuclear Information System (INIS)

Bellomunno, C.; Bonanomi, D.; Falciola, L.; Longhi, M.; Mussini, P.R.; Doubova, L.M.; Di Silvestro, G.

2005-01-01

A wide investigation on the electrochemical activity of four model organic bromides has been carried out in acetonitrile on nine cathodes of widely different affinity for halide anions (Pt, Zn, Hg, Sn, Bi, Pb, Au, Cu, Ag), and the electrocatalytic activities of the latter have been evaluated with respect to three possible inert reference cathode materials, i.e. glassy carbon, boron-doped diamond, and fluorinated boron-doped diamond. A general electrocatalytic activity scale for the process is proposed, with a discussion on its modulation by the configuration of the reacting molecule, and its connection with thermodynamic parameters accounting for halide adsorption

Reaction path of energetic materials using THOR code

Science.gov (United States)

Durães, L.; Campos, J.; Portugal, A.

1998-07-01

The method of predicting reaction path, using THOR code, allows for isobar and isochor adiabatic combustion and CJ detonation regimes, the calculation of the composition and thermodynamic properties of reaction products of energetic materials. THOR code assumes the thermodynamic equilibria of all possible products, for the minimum Gibbs free energy, using HL EoS. The code allows the possibility of estimating various sets of reaction products, obtained successively by the decomposition of the original reacting compound, as a function of the released energy. Two case studies of thermal decomposition procedure were selected, calculated and discussed—pure Ammonium Nitrate and its based explosive ANFO, and Nitromethane—because their equivalence ratio is respectively lower, near and greater than the stoicheiometry. Predictions of reaction path are in good correlation with experimental values, proving the validity of proposed method.

An archival study on the reacting plasma project (R-project) at the institute of plasma physics, Nagoya University. An interview with MATSUURA Kiyokata, professor emeritus at Nagoya University

Energy Technology Data Exchange (ETDEWEB)

Terashima, Y [Nagoya Univ., Nagoya, Aichi (Japan); Obayashi, H; Fujita, J; Namba, C; Kimura, K; Matsuoka, K; Hanaoka, S [National Inst. for Fusion Science, Toki, Gifu (Japan)

2006-01-15

An interview record with MATSUURA Kiyokata, Professor Emeritus at Nagoya University, is given on the Reacting Plasma Project (R-project), which was proposed and investigated in 1980's by the Institute of Plasma Physics, Nagoya University (IPP Nagoya). The project was planned to aim at producing a DT reacting plasma in tokamak to explore its physics and technology. But after intensive studies on design work, together with some R and D efforts and related investigations, the project could not be realized. The circumstances of the R-Project at its initiation and termination stages are the major topics of the present interview, held as a round-table talk with Prof. Matsuura, the project leader. (author)

Chemical signal activation of an organocatalyst enables control over soft material formation.

Science.gov (United States)

Trausel, Fanny; Maity, Chandan; Poolman, Jos M; Kouwenberg, D S J; Versluis, Frank; van Esch, Jan H; Eelkema, Rienk

2017-10-12

Cells can react to their environment by changing the activity of enzymes in response to specific chemical signals. Artificial catalysts capable of being activated by chemical signals are rare, but of interest for creating autonomously responsive materials. We present an organocatalyst that is activated by a chemical signal, enabling temporal control over reaction rates and the formation of materials. Using self-immolative chemistry, we design a deactivated aniline organocatalyst that is activated by the chemical signal hydrogen peroxide and catalyses hydrazone formation. Upon activation of the catalyst, the rate of hydrazone formation increases 10-fold almost instantly. The responsive organocatalyst enables temporal control over the formation of gels featuring hydrazone bonds. The generic design should enable the use of a large range of triggers and organocatalysts, and appears a promising method for the introduction of signal response in materials, constituting a first step towards achieving communication between artificial chemical systems.Enzymes regulated by chemical signals are common in biology, but few such artificial catalysts exist. Here, the authors design an aniline catalyst that, when activated by a chemical trigger, catalyses formation of hydrazone-based gels, demonstrating signal response in a soft material.

Activation of Ca(OH){sub 2} using different siliceous materials

Energy Technology Data Exchange (ETDEWEB)

Karatepe, N.; Ersoy-Mericboyu, A.; Kucukbayrak, S. [Istanbul Technical University, Istanbul (Turkey)

1999-04-01

Siliceous materials such as silica fume, bentonite and diatomite were mixed with Ca(OH){sub 2} and hydrated at different conditions to produce reactive SO{sub 2} sorbents. Two different hydration methods were used, namely atmospheric and pressure hydration. The effects of the hydration temperature, time and siliceous material/Ca(OH){sub 2} weight ratio on the physical properties of the activated sorbents wereinvestigated. A statistical design technique was applied by use of a two-level factorial design matrix to interpret experimental results. In atmospheric hydration, it was found that increasing the temperature and hydration time caused an increase in the total surface area of the sorbents. But, increasing the siliceous material/Ca(OH){sub 2} weight ratio caused a decrease in the total surface area of the sorbents. In pressure hydration, mathematical analysis showed that the surface area of the activated sorbents was positively affected by the hydration variables. Thermogravimetric measurements showed that increasing the amount of reacted Ca(OH){sub 2} during hydration caused an increase in the surface area of the sorbent. X-ray diffraction studies also indicated that calcium silicate hydrates were the principal Ca-containing species formed during hydration.

Mechanically Strong Lightweight Materials for Aerospace Applications (x-aerogels)

Science.gov (United States)

Leventis, Nicholas

2005-01-01

The X-Aerogel is a new NASA-developed strong lightweight material made by reacting the mesoporous surfaces of 3-D networks of inorganic nanoparticles with polymeric crosslinkers. Since the relative amount of the crosslinker and the backbone are comparable, X-Aerogels can be viewed either as aerogels modified by templated accumulation of polymer on the skeletal nanoparticles, or as nanoporous polymers made by templated casting of polymeric precursors on a nanostructured framework. The most striking feature of X-Aerogels is that for a nominal 3-fold increase in density (still a ultralightweight material), the mechanical strength can be up to 300 times higher than the strength of the underlying native aerogel. Thus, X-Aerogels combine a multiple of the specific compressive strength of steel, with the thermal conductivity of styrofoam. XAerogels have been demonstrated with several polymers such as polyurethanes/polyureas, epoxies and polyolefins, while crosslinking of approximately 35 different oxide aerogels yields a wide variety of dimensionally stable, porous lightweight materials with interesting structural, magnetic and optical properties. X-Aerogels are evaluated for cryogenic rocket fuel storage tanks and for Advanced EVA suits, where they will play the dual role of the thermal insulator/structural material. Along the same lines, major impact is also expected by the use of X-Aerogels in structural components/thermal protection for small satellites, spacecrafts, planetary vehicles and habitats.

Development and test of a Nb3Sn racetrack magnet using the react and wind technology

International Nuclear Information System (INIS)

Ambrosio, G.; Andreev, N.; Barzi, E.; Bauer, P.; Carcagno, R.; Chichili, D.; Ewald, K.; Feher, S.; Imbasciati, L.; Kashikhin, V. V.; Limon, P.; Novitski, I.; Orris, D.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.; Tompkins, J.; Yadav, S.; Zlobin, A.V.

2002-01-01

Fermilab is involved in the development of a high field accelerator magnet for future hadron colliders using Nb 3 Sn superconductor and the react-and-wind technology. The magnet design is based on single-layer common coils wound simultaneously into a laminated mechanical structure and impregnated with epoxy. In order to develop and optimize the fabrication techniques and to study the conductor performance, a magnet with flat racetrack type coils in a common coil configuration was assembled and tested. The coils were wound in the mechanical structure and in situ impregnated following a procedure that will be used in the single-layer common coil. The magnetic and mechanical design of the racetrack magnet, the fabrication techniques and the test results are presented and discussed in this paper

Measurement of properties of sealant materials for solid oxide fuel cell systems

International Nuclear Information System (INIS)

Boersma, R.J.; Sammes, N.M.; Zhang, Y.

1998-01-01

Thermal expansion of ceramic materials, ceramic cements and steels was studied, and their compatibility with materials used in the SOFC system was evaluated. A number of ceramic cements, a glass paste and a glass ceramic were examined to identify their potential as a sealing material in a tubular fuel cell system. Thermal expansion coefficients of these materials were compared for thermal matching with materials employed in the fuel cell construction, such as yttria stabilised with 8 mole% zirconia (8YSZ) and stainless steel. A reasonable match was found for Macor, a glass ceramic, with one of the steel samples studied and with 8YSZ. Candidate sealants were tested for bonding quality, which made it evident that the ceramic cements had to be discarded. Good bonds between Macor and one of the steel samples and Macor and 8YSZ were formed, resulting in a gas tight seal. Uncertainty remains regarding the long term effect of the interface reactions between steel and Macor. Exposure of the Macor and a steel-Macor-8YSZ assembly to the different fuel cell gas atmospheres revealed that the Macor reacts with hydrogen, the long term effect of which is also unknown. Copyright (1998) Australasian Ceramic Society

Synthesis and Application of Jatropha Oil based Polyurethane as Paint Coating Material

Directory of Open Access Journals (Sweden)

Zainal Alim Mas’ud

2012-08-01

Full Text Available Recently, the use of renewable sources in the preparation of various industrial materials has been revitalized in response to environmental concerns. Natural oils are considered to be the most important genre of renewable sources. Jatropha curcas oil (JPO based polyol is an alternative material that may possibly replace petrochemical-based polyol for polyurethane coating material. Polyurethane was synthesized by reacting JPO-based polyol with isocyanate. To produce JPO-based polyol, JPO was first epoxidized to form epoxidized J. curcas oil (EJP, subsequently it was converted to polyol by the opening ring reaction with acrylic acid (AA using triethylamine (TEA as a catalyst. The JPO-based polyurethane film resulting from this study is compared with polyurethane film from commercial polyol for gloss, hardness, and adhesion quality. The result showed that the source of polyol has an influence on gloss, hardness, and adhesion of polyurethane film, but the differences with using isocyanate has less influence. Using visual observation, polyurethane film produced from L.OHV polyol, H.OHV polyol and commercial polyol have similar quality.

Stereodynamics of Ne(3P2) reacting with Ar, Kr, Xe, and N2

Science.gov (United States)

Zou, Junwen; Gordon, Sean D. S.; Tanteri, Silvia; Osterwalder, Andreas

2018-04-01

Stereodynamics experiments of Ne(3P2) reacting with Ar, Kr, Xe, and N2 leading to Penning and associative ionization have been performed in a crossed molecular beam apparatus. A curved magnetic hexapole was used to state-select and polarize Ne(3P2) atoms which were then oriented in a rotatable magnetic field and crossed with a beam of Ar, Kr, Xe, or N2. The ratio of associative to Penning ionization was recorded as a function of the magnetic field direction for collision energies between 320 cm-1 and 500 cm-1. Reactivities are obtained for individual states that differ only in Ω, the projection of the neon total angular momentum vector on the inter-particle axis. The results are rationalized on the basis of a model involving a long-range and a short-range reaction mechanism. Substantially lower probability for associative ionization was observed for N2, suggesting that predissociation plays a critical role in the overall reaction pathway.

ENHANCING STUDENTS‟ MOTIVATION AND ACHIEVEMENT IN LEARNING GRAMMAR THROUGH CONTEXTUAL TEACHING AND LEARNING THROUGH RELATING, EXPERIENCING, APPLYING, COOPERATING AND TRANSFERRING (REACT STRATEGY

Directory of Open Access Journals (Sweden)

Mashlihatul Umami Umami

2017-04-01

Full Text Available This research addresses the issue of whether Contextual Teaching and Learning (CTL through REACT (Relating, Experiencing, Applying, Cooperating and Transferring strategy is able to enhance motivation and achievement of English Department students‘ in learning grammar. The researcher uses a classroom action research in which it was held for about two cycles. The instruments of collecting the data are observation, rubric, questionaire and test. The researcher analyzes the data using three steps, i.e. students‘ motivation to learn are analyzed by the sheet of observation, each of individuals is also analyzed by fulfilling the questionnaire of self assessment, the progress of students‘ motivation and achievement are all monitored by rubric assessment tool, seven components of REACT strategy in learning is also recorded by the sheets of observation and the statistical analysis using t-test measures the improvement occurred. In addition, the researcher prepares field note and questionnaire to monitor the process of learning. Based on the results of qualitative-quantitative analysis, it can be found that the use of CTL approach especially using project based and cooperative learning improves the students‘ motivation and achievement in learning grammar.

The carbon price: a toothless tool for material efficiency?

Science.gov (United States)

Skelton, Alexandra C H; Allwood, Julian M

2017-06-13

This article explores whether a carbon price will effectively encourage the more efficient use of greenhouse gas intensive materials such as steel. The article identifies a range of distortions that arise when some of the restrictive assumptions of neoclassical economics are relaxed. Distortions occur due to the sequential nature of decision-making along supply chains, due to imperfect competition and due to government intervention to reduce the risk of carbon leakage. If upstream sectors do not pass on carbon costs, downstream sectors do not have the opportunity to react. Of the distortions identified, compensation mechanisms that reduce the risk of carbon leakage are likely to act as the greatest hinderance to appropriate incentives for the more efficient use of steel in the UK: as things currently stand, unless upstream companies are encouraged to make windfall profits, incentives downstream are weakened. The article concludes by exploring policy options to address the distortions identified, including efforts to reinstate the carbon price downstream and efforts to remove other distortive taxes.This article is part of the themed issue 'Material demand reduction'. © 2017 The Authors.

Fixation by ion exchange of toxic materials in a glass matrix

International Nuclear Information System (INIS)

Simmons, C.J.; Simmons, J.H.; Macedo, P.B.; Litovitz, T.A.

1982-01-01

A process is reported for reacting a porous silicate or borosilicate glass or silica gel with alkali metal cations, Group lb cations and/or ammonium cations bonded to the silicon through divalent oxygen linkages on the internal surfaces of the pores. Ion exchange of the cations with toxic or radioactive cations was possible resulting in a distribution of internal silicon-bonded toxic cation oxide groups within the pores of the glass or silica gel. The ion exchange reaction may be done successfully with acidic, neutral or alkaline pH solutions. The aim of the immobilization is for permanent storage of hazardous materials such as Hg 2+ , Hg + , Cd 2+ , Tl + , Pb 2+ and radioactive cations

How relay protection and automatic control systems react to the energizing of a 500 kV line

Energy Technology Data Exchange (ETDEWEB)

Gusev, V S; Kokovich, V E; Ovchinnikov, V V

1966-04-01

When the three phases of a 500 to 750 KV line are switched on to load by existing types of circuit breaker, a heavy aperiodic component of current appears in the secondaries of the neutral current transformers. The dc component, although damped, has a relatively long decay period. This effect is particularly evident in the case of high speed or nonsynchronized autoreclosure. The presence of such a large dc component can cause maloperation of the line earth fault protection unless special precautions are taken. Two complementary solutions are described, preventing the first stage earth fault protection from reacting to the aperiodic component, and reducing the time constant of the CT secondary circuits.

[Effect of previous experience in reacting to a danger signal on "open field" behavior in the rat].

Science.gov (United States)

Poltyreva, T E; Petrov, E S

1983-01-01

Modification of rats behaviour in an "hopen field" test was investigated, induced by an acoustic stimulus, previously subjected to conditioning in a shuttle chamber in experiments with possibility and impossibility of avoidance from electrical shock. It has been established that presentation of a stimulus having the meaning of a danger signal, in a new situation, significantly suppresses investigating behaviour of rats, whereas the stimulus which had not been subjected to conditioning exerts no marked effect on behaviour. The greatest suppression was observed in rats with "learned helplessness". This fact suggests that the degree of suppression of the behaviour in an open field in response to a danger signal, depends on the animal's previous experience in reacting to this signal.

Multiphase integral reacting flow computer code (ICOMFLO): User`s guide

Energy Technology Data Exchange (ETDEWEB)

Chang, S.L.; Lottes, S.A.; Petrick, M.

1997-11-01

A copyrighted computational fluid dynamics computer code, ICOMFLO, has been developed for the simulation of multiphase reacting flows. The code solves conservation equations for gaseous species and droplets (or solid particles) of various sizes. General conservation laws, expressed by elliptic type partial differential equations, are used in conjunction with rate equations governing the mass, momentum, enthalpy, species, turbulent kinetic energy, and turbulent dissipation. Associated phenomenological submodels of the code include integral combustion, two parameter turbulence, particle evaporation, and interfacial submodels. A newly developed integral combustion submodel replacing an Arrhenius type differential reaction submodel has been implemented to improve numerical convergence and enhance numerical stability. A two parameter turbulence submodel is modified for both gas and solid phases. An evaporation submodel treats not only droplet evaporation but size dispersion. Interfacial submodels use correlations to model interfacial momentum and energy transfer. The ICOMFLO code solves the governing equations in three steps. First, a staggered grid system is constructed in the flow domain. The staggered grid system defines gas velocity components on the surfaces of a control volume, while the other flow properties are defined at the volume center. A blocked cell technique is used to handle complex geometry. Then, the partial differential equations are integrated over each control volume and transformed into discrete difference equations. Finally, the difference equations are solved iteratively by using a modified SIMPLER algorithm. The results of the solution include gas flow properties (pressure, temperature, density, species concentration, velocity, and turbulence parameters) and particle flow properties (number density, temperature, velocity, and void fraction). The code has been used in many engineering applications, such as coal-fired combustors, air

Steam bubble growth in the bulk of overheated N2O4-NO chemically reacting solution

International Nuclear Information System (INIS)

Nemtsev, V.A.; Cherkashin, A.M.

1989-01-01

A mathematical model and numerical investigation of the vapour bubble growth that begins from the bubble critical size at the positive radius fluctuation during the initial moment in the bulk of the overheated N 2 O 4 -NO liquid solution are presented. The mathematical model has been stated under the following assumptions: the movement of a bubble wall and surrounding liquid is spherically symmetrical; thermal parameters in the bubble are distributed uniformly; the vapour phase follows the ideal gas law; heat transfer is not affected by the compressibility of liquid; if dissolution of light components is determined by Henry's law, then Hertz-Knudsen's equation determines the velocity of phase transition for a N 2 O 4 component. The mathematical model presented can be applied to another fluids, including chemically reacting ones

Stabilization/Solidification of radioactive molten salt waste by using xSiO{sub 2}-yAl{sub 2}O{sub 3}-zP{sub 2}O{sub 5} material

Energy Technology Data Exchange (ETDEWEB)

Hwan-Seo Park; In-Tae Kim; Yong-Zun Cho; Seong-Won Park; Eung-Ho Kim [Korea Atomic Energy Research Institute: 150 Deokjin-dong, Yuseong, Daejeon, 305-353 (Korea, Republic of)

2008-07-01

Molten salt waste generated from the electro metallurgical process to recover uranium and transuranic elements is considered as one of problematic wastes to be difficult to immobilize into a durable for final disposal. As an alternative, this study suggested a new method performed at molten state, where dechlorination was achieved with a new inorganic material containing SiO{sub 2}, Al{sub 2}O{sub 3} and P{sub 2}O{sub 5} (SAP). The SAP as a reactive material to molten salt was prepared by a conventional sol-gel process. The prepared SAPs were reacted with each metal chloride, LiCl, CsCl, SrCl{sub 2} and CeCl{sub 3} at 650 deg. C for 6 hours and also were reacted with simulated salt waste consisting of 90 wt% LiCl, 6.8 wt% CsCl and 3.2 wt% SrCl{sub 2} at different waste loading. All the reactions were carried out in oxidative atmosphere and metal chlorides were effectively converted into stable products under a reasonable reaction ratio.

Effect of hydrogen on reduction of burden materials

Energy Technology Data Exchange (ETDEWEB)

Hooey, P.L. [Rautaruukki Oy, Raahe (Finland). Raahe Steel

1996-12-31

Efficient operation of iron blast furnaces requires that the iron bearing burden material have good reduction, softening and melting characteristics. These characteristics are determined by the physical operation of the blast furnace and the mineralogical composition of the agglomerate. Increasing oil injection rates will increase the hydrogen content of the reducing gas significantly. The aim of this work is to establish how different burden materials react to this change in gas environment, and develop sinters which have optimal properties. The testing of sinter and pellets is broken into two areas: development of the test methods; and determination of sinter and pellet characteristics. The test method requires development because recent testwork has shown that the reducibility of the sinter is now so high that the reduction under load test is no longer sensitive. A new control program and more realistic gas compositions are currently being tested. The softening and melting characteristics of sinters of varying composition, acid pellets and olivine pellets have been tested using the reduction under load test at Rautaruukki Oy Research Centre. The effect of hydrogen in the reducing gas on the different iron ore agglomerates has been evaluated SULA 2 Research Programme; 6 refs.

Effect of hydrogen on reduction of burden materials

Energy Technology Data Exchange (ETDEWEB)

Hooey, P L [Rautaruukki Oy, Raahe (Finland). Raahe Steel

1997-12-31

Efficient operation of iron blast furnaces requires that the iron bearing burden material have good reduction, softening and melting characteristics. These characteristics are determined by the physical operation of the blast furnace and the mineralogical composition of the agglomerate. Increasing oil injection rates will increase the hydrogen content of the reducing gas significantly. The aim of this work is to establish how different burden materials react to this change in gas environment, and develop sinters which have optimal properties. The testing of sinter and pellets is broken into two areas: development of the test methods; and determination of sinter and pellet characteristics. The test method requires development because recent testwork has shown that the reducibility of the sinter is now so high that the reduction under load test is no longer sensitive. A new control program and more realistic gas compositions are currently being tested. The softening and melting characteristics of sinters of varying composition, acid pellets and olivine pellets have been tested using the reduction under load test at Rautaruukki Oy Research Centre. The effect of hydrogen in the reducing gas on the different iron ore agglomerates has been evaluated SULA 2 Research Programme; 6 refs.

Analysis of the trend to equilibrium of a chemically reacting system

International Nuclear Information System (INIS)

Kremer, Gilberto M; Bianchi, Miriam Pandolfi; Soares, Ana Jacinta

2007-01-01

In this present paper, a quaternary gaseous reactive mixture, for which the chemical reaction is close to its final stage and the elastic and reactive frequencies are comparable, is modelled within the Boltzmann equation extended to reacting gases. The main objective is a detailed analysis of the non-equilibrium effects arising in the reactive system A 1 + A 2 ↔ A 3 + A 4 , in a flow regime which is considered not far away from thermal, mechanical and chemical equilibrium. A first-order perturbation solution technique is applied to the macroscopic field equations for the spatially homogeneous gas system, and the trend to equilibrium is studied in detail. Adopting elastic hard-spheres and reactive line-of-centres cross sections and an appropriate choice of the input distribution functions-which allows us to distinguish the two cases where the constituents are either at same or different temperatures-explicit computations of the linearized production terms for mass, momentum and total energy are performed for each gas species. The departures from the equilibrium states of densities, temperatures and diffusion fluxes are characterized by small perturbations of their corresponding equilibrium values. For the hydrogen-chlorine system, the perturbations are plotted as functions of time for both cases where the species are either at the same or different temperatures. Moreover, the trend to equilibrium of the reaction rates is represented for the forward and backward reaction H 2 + Cl ↔ HCl + H

Composite Materials With Uncured Epoxy Matrix Exposed in Stratosphere During NASA Stratospheric Balloon Flight

Science.gov (United States)

Kondyurin, Alexey; Kondyurina, Irina; Bilek, Marcela; de Groh, Kim K.

2013-01-01

A cassette of uncured composite materials with epoxy resin matrixes was exposed in the stratosphere (40 km altitude) over three days. Temperature variations of -76 to 32.5C and pressure up to 2.1 torr were recorded during flight. An analysis of the chemical structure of the composites showed, that the polymer matrix exposed in the stratosphere becomes crosslinked, while the ground control materials react by way of polymerization reaction of epoxy groups. The space irradiations are considered to be responsible for crosslinking of the uncured polymers exposed in the stratosphere. The composites were cured on Earth after landing. Analysis of the cured composites showed that the polymer matrix remains active under stratospheric conditions. The results can be used for predicting curing processes of polymer composites in a free space environment during an orbital space flight.

IGHV1-69-Encoded Antibodies Expressed in Chronic Lymphocytic Leukemia React with Malondialdehyde-Acetaldehyde Adduct, an Immunodominant Oxidation-Specific Epitope

DEFF Research Database (Denmark)

Que, Xuchu; Widhopf Ii, George F; Amir, Shahzada

2013-01-01

The immunoglobulins expressed by chronic lymphocytic leukemia (CLL) B cells are highly restricted, suggesting they are selected for binding either self or foreign antigen. Of the immunoglobulin heavy-chain variable (IGHV) genes expressed in CLL, IGHV1-69 is the most common, and often is expressed...... are products of enhanced lipid peroxidation and a major target of innate natural antibodies. Specifically, CLL69C bound immunodominant OSE adducts termed MAA (malondialdehyde-acetaldehyde-adducts), which are found on apoptotic cells, inflammatory tissues, and atherosclerotic lesions. It also reacted...

Test Results of a Nb3Sn Wind/React ''Stress-Managed'' Block Dipole

International Nuclear Information System (INIS)

McInturff, A.; Bish, P.; Blackburn, R.; Diaczenko, N.; Elliott, T.; Hafalia Jr., R.; Henchel, W.; Jaisle, A.; Lau, W.; Lietzke, A.; McIntyre, P.; Noyes, P.; Nyman, M.; Sattarov, A.; Sattarov, A.

2006-01-01

A second phase of a highfield dipole technology development has been tested. A Nb3Sn block-coil model dipole was fabricated, using magnetic mirror geometry and wind/react coil technology. The primary objective of this phase was to make a first experimental test of the stress-management strategy pioneered at Texas A and M. In this strategy a high-strength support matrix is integrated with the windings to intercept Lorentz stress from the inner winding so that it does not accumulate in the outer winding. The magnet attained a field that was consistent with short sample limit on the first quench; there was no training. The decoupling of Lorentz stress between inner and outer windings was validated. In ramp rate studies the magnet exhibited a remarkable robustness in rapid ramping operation. It reached 85 percent of short sample(ss) current even while ramping 2-3 T/s. This robustness is attributed to the orientation of the Rutherford cables parallel to the field in the windings, instead of the transverse orientation that characterizes common dipole designs. Test results are presented and the next development phase plans are discussed

''A Parallel Adaptive Simulation Tool for Two Phase Steady State Reacting Flows in Industrial Boilers and Furnaces''; FINAL

International Nuclear Information System (INIS)

Michael J. Bockelie

2002-01-01

This DOE SBIR Phase II final report summarizes research that has been performed to develop a parallel adaptive tool for modeling steady, two phase turbulent reacting flow. The target applications for the new tool are full scale, fossil-fuel fired boilers and furnaces such as those used in the electric utility industry, chemical process industry and mineral/metal process industry. The type of analyses to be performed on these systems are engineering calculations to evaluate the impact on overall furnace performance due to operational, process or equipment changes. To develop a Computational Fluid Dynamics (CFD) model of an industrial scale furnace requires a carefully designed grid that will capture all of the large and small scale features of the flowfield. Industrial systems are quite large, usually measured in tens of feet, but contain numerous burners, air injection ports, flames and localized behavior with dimensions that are measured in inches or fractions of inches. To create an accurate computational model of such systems requires capturing length scales within the flow field that span several orders of magnitude. In addition, to create an industrially useful model, the grid can not contain too many grid points - the model must be able to execute on an inexpensive desktop PC in a matter of days. An adaptive mesh provides a convenient means to create a grid that can capture both fine flow field detail within a very large domain with a ''reasonable'' number of grid points. However, the use of an adaptive mesh requires the development of a new flow solver. To create the new simulation tool, we have combined existing reacting CFD modeling software with new software based on emerging block structured Adaptive Mesh Refinement (AMR) technologies developed at Lawrence Berkeley National Laboratory (LBNL). Specifically, we combined: -physical models, modeling expertise, and software from existing combustion simulation codes used by Reaction Engineering International

Slag of Greek provenance uses in materials science and geophysics: implications for a highly potential material in the service of the development of Greek economy

Science.gov (United States)

Leontakianakos, G.; Baziotis, I.; Sotiriadis, K.; Goulas, G.; Liakopoulos, S.; Karastathis, V.

2012-04-01

Ground granulated blast-furnace slag (GGBS) is a secondary raw material that can be used as an alternative low energy binder. Hydraulic properties can be occurred through its alkali activation. GGBS is characterized by the glassy to crystalline ratio and by its chemical and mineralogical composition. Acidic slag cannot easily get crystallized in oppose to the basic one. Crystalline phases show very low reactivity with Ca(OH)2, while amorphous phases can easily react in the presence of basic substances. The aim of the present study was to study the evolution of new advanced silicate materials presenting high durability at high temperature environments. Specimens were produced using two types of slag of Greek origin. The first type was a ferrous slag, while the second one was calcareous. Their maximum particle size was 4 mm and 0.07 mm respectively. Specimens were prepared using the above slag types and siliceous sand as an aggregate. Sand was divided according to European Standard EN 196-1 in three fractions: PG1 (1Greek origin is a material with a significant potential to be used in the field of building constructions protection against high temperatures. Though, it is an extremely promising material of highly potential value which can turn it into to the accessory part of the steam engine for sustainable development of the Greek economy.

Acceleration of tritons with a compact cyclotron

International Nuclear Information System (INIS)

Wegmann, H.; Huenges, E.; Muthig, H.; Moringa, H.

1981-01-01

With the compact cyclotron at the Faculty of Physics of the Technical University of Munich, tritons have been accelerated to an energy of 7 MeV. A safe and reliable operation of the gas supply for the ion source was obtained by a new tritium storage system. A quantity of 1500 Ci tritium is stored by two special Zr-Al getter pumps in a non-gaseous phase. The tritium can be released in well-defined amounts by heating the getter material. During triton acceleration the pressure in the cyclotron vacuum chamber is maintained only by a large titanium sputter-ion pump, thus forming a closed vacuum system without any exhaust of tritium contaminated gas. Any tritium contaminations in the air can be detected by an extremely sensitive tritium monitoring system. The triton beam with a maximum intensity of 30 μA has been used so far to produce neutron-rich radioisotopes such as 28 Mg, 43 K, or 72 Zn, which are successfully applied in tracer techniques in the studies of biological systems. (orig.)

Toxicology of oil field pollutants in cattle: a review.

Science.gov (United States)

Coppock, R W; Mostrom, M S; Khan, A A; Semalulu, S S

1995-12-01

Cattle are poisoned by petroleum and substances used in drilling and operating oil and gas wells. The most common reported route of exposure for non-gaseous material is oral. Exposures occur when the petroleum or chemicals used in oil and gas field activities are available to cattle and when water and feed-stuffs are contaminated. Cattle, as a leisure activity, explore and ingest crude oil. Based on morbidity patterns in cattle herds, the amount of toxic substance ingested is variable. When water and feedstuffs are contaminated, a larger number in a herd generally are affected. Cattle have been poisoned by a wide variety of chemical mixtures. For substances high in volatile hydrocarbons, the lung is a target organ. Hydrocarbons also target the kidney, liver and brain. Exposure-linked abortions have been reported in cattle. Diethylene glycol targets the brain, liver and kidney. The reported threshold dose of unweathered oil for cattle ranges from 2.5 to 5.0 ml/kg bw, and the reported threshold dose for weathered oil is 8.0 ml/kg.

Application of secondary ion mass spectrometry for the characterization of commercial high performance materials

International Nuclear Information System (INIS)

Gritsch, M.

2000-09-01

The industry today offers an uncounted number of high performance materials, that have to meet highest standards. Commercial high performance materials, though often sold in large quantities, still require ongoing research and development to keep up to date with increasing needs and decreasing tolerances. Furthermore, a variety of materials is on the market that are not fully understood in their microstructure, in the way they react under application conditions, and in which mechanisms are responsible for their degradation. Secondary Ion Mass Spectrometry (SIMS) is an analytical method that is now in commercial use for over 30 years. Its main advantages are the very high detection sensitivity (down to ppb), the ability to measure all elements with isotopic sensitivity, the ability of gaining laterally resolved images, and the inherent capability of depth-profiling. These features make it an ideal tool for a wide field of applications within advanced material science. The present work gives an introduction into the principles of SIMS and shows the successful application for the characterization of commercially used high performance materials. Finally, a selected collection of my publications in reviewed journals will illustrate the state of the art in applied materials research and development with dynamic SIMS. All publications focus on the application of dynamic SIMS to analytical questions that stem from questions arising during the production and improvement of high-performance materials. (author)

Methane reacts with heteropolyacids chemisorbed on silica to produce acetic acid under soft conditions

KAUST Repository

Sun, Miao

2013-01-16

Selective functionalization of methane at moderate temperature is of crucial economic, environmental, and scientific importance. Here, we report that methane reacts with heteropolyacids (HPAs) chemisorbed on silica to produce acetic acid under soft conditions. Specially, when chemisorbed on silica, H 4SiW12O40, H3PW12O 40, H4SiMo12O40, and H 3PMo12O40 activate the primary C-H bond of methane at room temperature and atmospheric pressure. With these systems, acetic acid is produced directly from methane, in a single step, in the absence of Pd and without adding CO. Extensive surface characterization by solid-state NMR spectroscopy, IR spectroscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy suggests that C-H activation of methane is triggered by the protons in the HPA-silica interface with concerted reduction of the Keggin cage, leading to water formation and hydration of the interface. This is the simplest and mildest way reported to date to functionalize methane. © 2012 American Chemical Society.

Non-gaseous radiolysis products of 6-aminopenicillanic acid and potassium salt of benzylepenicillin

International Nuclear Information System (INIS)

Dziegielewski, J.; Jezowska-Trzebiatowska, B.; Siemion, I.Z.

1974-01-01

The radiolysis products of 6-aminopenicillanic acid (6-APA) and potassium salt of benzylpenicillin G, irradiated with γ-rays were separated by the extraction methods and chromatographically by the thin-layer method. On the basis of the IR and UV spectroscopic investigations as well as by the NMR and mass spectrometry methods of the radiolysis products, the paths of the radiation decomposition of 6-APA and of penicillin G were determined. (author)

Vanadium oxide based cpd. useful as a cathode active material - is used in lithium or alkali metal batteries to prolong life cycles

DEFF Research Database (Denmark)

1997-01-01

A mixt. of metallic iron particles and vanadium pentoxide contg. V in its pentavalent state in a liq. is reacted to convert at least some of the pentavalent V to its tetravalent state and form a gel. The liq. phase is then sepd. from the oxide based gel to obtain a solid material(I) comprising Fe......, V and oxygen where at least some of the V is in the tetravalent state. USE-(I) is a cathode active material in electric current producing storage cells. ADVANTAGE-Use of (I) in Li or alkali metal batteries gives prolonged life cycles.Storage cells using (I) have improved capacity during charge...

Direct numerical simulation of an isothermal reacting turbulent wall-jet

Science.gov (United States)

Pouransari, Zeinab; Brethouwer, Geert; Johansson, Arne V.

2011-08-01

In the present investigation, Direct Numerical Simulation (DNS) is used to study a binary irreversible and isothermal reaction in a plane turbulent wall-jet. The flow is compressible and a single-step global reaction between an oxidizer and a fuel species is solved. The inlet based Reynolds, Schmidt, and Mach numbers of the wall-jet are Re = 2000, Sc = 0.72, and M = 0.5, respectively, and a constant coflow velocity is applied above the jet. At the inlet, fuel and oxidizer enter the domain separately in a non-premixed manner. The turbulent structures of the velocity field show the common streaky patterns near the wall, while a somewhat patchy or spotty pattern is observed for the scalars and the reaction rate fluctuations in the near-wall region. The reaction mainly occurs in the upper shear layer in thin highly convoluted reaction zones, but it also takes place close to the wall. Analysis of turbulence and reaction statistics confirms the observations in the instantaneous snapshots, regarding the intermittent character of the reaction rate near the wall. A detailed study of the probability density functions of the reacting scalars and comparison to that of the passive scalar throughout the domain reveals the significance of the reaction influence as well as the wall effects on the scalar distributions. The higher order moments of both the velocities and the scalar concentrations are analyzed and show a satisfactory agreement with experiments. The simulations show that the reaction can both enhance and reduce the dissipation of fuel scalar, since there are two competing effects; on the one hand, the reaction causes sharper scalar gradients and thus a higher dissipation rate, on the other hand, the reaction consumes the fuel scalar thereby reducing the scalar dissipation.

Direct Numerical Simulation of a Compressible Reacting Boundary Layer using a Temporal Slow Growth Homogenization

Science.gov (United States)

Topalian, Victor; Oliver, Todd; Ulerich, Rhys; Moser, Robert

2013-11-01

A DNS of a compressible, reacting boundary layer flow at Reθ ~ 430 was performed using a temporal slow-growth homogenization, for a multispecies flow model of air at supersonic regime. The overall scenario parameters are related to those of the flow over an ablating surface of a space capsule upon Earth's atmospheric re-entry. The simulation algorithm features Fourier spatial discretization in the streamwise and spanwise directions, B-splines in the wall normal direction, and is marched semi-implicitly in time using the SMR91 scheme. Flow statistics will be presented for relevant flow quantities, in particular those related with RANS modeling. Since analogous slow growth computations can be performed using RANS to predict the flow mean profiles, the use of data gathered from this type of simulation as a vehicle for the calibration and uncertainty quantification of RANS models will be discussed. This work is supported by the Department of Energy [National Nuclear Security Administration] under Award Number [DE-FC52-08NA28615].

Phenolic cation exchange resin material for recovery of cesium and strontium

Science.gov (United States)

Ebra, Martha A.; Wallace, Richard M.

1983-01-01

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear waste solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs.sup.+ and Sr.sup.2+ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

Effect of turbulent model closure and type of inlet boundary condition on a Large Eddy Simulation of a non-reacting jet with co-flow stream

International Nuclear Information System (INIS)

Payri, Raul; López, J. Javier; Martí-Aldaraví, Pedro; Giraldo, Jhoan S.

2016-01-01

Highlights: • LES in a non-reacting jet with co-flow is performed with OpenFoam. • Smagorinsky (SMAG) and One Equation Eddy (OEE) approaches are compared. • A turbulent pipe is used to generate and map coherent inlet turbulence structure. • Fluctuating inlet boundary condition requires much less computational cost. - Abstract: In this paper, the behavior and turbulence structure of a non-reacting jet with a co-flow stream is described by means of Large Eddy Simulations (LES) carried out with the computational tool OpenFoam. In order to study the influence of the sub-grid scale (SGS) model on the main flow statistics, Smagorinsky (SMAG) and One Equation Eddy (OEE) approaches are used to model the smallest scales involved in the turbulence of the jet. The impact of cell size and turbulent inlet boundary condition in resulting velocity profiles is analyzed as well. Four different tasks have been performed to accomplish these objectives. Firstly, the simulation of a turbulent pipe, which is necessary to generate and map coherent turbulence structure into the inlet of the non-reacting jet domain. Secondly, a structured mesh based on hexahedrons has been built for the jet and its co-flow. The third task consists on performing four different simulations. In those, mapping statistics from the turbulent pipe is compared with the use of fluctuating inlet boundary condition available in OpenFoam; OEE and SMAG approaches are contrasted; and the effect of changing cell size is investigated. Finally, as forth task, the obtained results are compared with experimental data. As main conclusions of this comparison, it has been proved that the fluctuating boundary condition requires much less computational cost, but some inaccuracies were found close to the nozzle. Also, both SGS models are capable to simulate this kind of jets with a co-flow stream with exactitude.

Improvement of airtight property and workability of joint packing material; Teikeimejizai no shirusei oyobi sagyosei no kaizen

Energy Technology Data Exchange (ETDEWEB)

Ouchi, Tatsuya.; Harada, Tsutomu.; Ando, Hideyuki.; Yamato, Tsugio. [Kurosaki Corp., Fukuoka (Japan). Technical Research Center

1999-09-01

It is connected, and many refractories s are being used with continuous cast law. An including air volume from these union parts causes the quality decline of the steel and the problem of unusual loss around the union part of the refractories. Therefore, there is a big thing in the part, which the eye area material used for the union part of the refractories for the continuous cast plays. This time, the fixed form area material of the hard type which has a sticker and work between the excellent heat could get it in comparison with the usual fixed form area material for the purpose of the improvement in the sticker of the eye area material and the work (acceptable convenience time in the normal temperature form, the space of the heat) as a result of examining the application of the Al metal which doesn`t react easily with the new binder and the water. As for the utility test as well, it is reported because it was used without problem and that validity could be confirmed. (NEDO)

Chemistry and Bioactivity of NeoMTA Plus™ versus MTA Angelus® Root Repair Materials

Directory of Open Access Journals (Sweden)

Sawsan T. Abu Zeid

2017-01-01

Full Text Available Objectives. To analyse the chemistry and bioactivity of NeoMTA Plus in comparison with the conventional root repair materials. Method and Materials. Unhydrated and hydrated (initial and final sets materials were analysed by Fourier transform infrared (FTIR spectroscopy and X-ray diffraction (XRD. For bioactivity study, small holes of dentin discs were filled with either materials, immersed in PBS for 15 days, and analysed with FTIR and scanning electron microscope with energy dispersive X-ray (SEM/EDX. The calculation of crystallinity and carbonate/phosphate (CO3/PO4 ratio of surface precipitates (from FTIR and calcium/phosphate (Ca/P ratio (from EDX was statistically analysed using t-test or ANOVA, respectively, at 0.05 significance. Results. Both materials are tricalcium silicate-based that finally react to be calcium silicate hydrate. NeoMTA Plus has relatively high aluminium and sulfur content, with tantalum oxide as an opacifier instead of zirconium oxide in MTA Angelus. NeoMTA Plus showed better apatite formation, higher crystallinity and Ca/P but lower CO3/PO4 ratio than MTA Angelus. SEM showed globular structure with a small particle size in NeoMTA Plus while spherical structure with large particle size in MTA Angelus. Conclusion. Due to fast setting, higher crystallinity, and better bioactivity of NeoMTA Plus, it can be used as a pulp and root repair material.

Thermal properties and modeling of aluminosilicate materials for low-temperature bulk applications

International Nuclear Information System (INIS)

Kaushal, S.

1988-01-01

This thesis concerns itself with the thermal properties of aluminosilicate materials such as cements, blended cements and clays and their application to the problem of radioactive waste encapsulation. The objective of this thesis is to study the thermal properties (heat of hydration, thermal conductivity and diffusivity) of these materials and to determine their effect on the temperature in large monoliths and on the material itself. In this thesis the hydration temperatures for the extreme conditions (adiabatic) were experimentally measured and compared to those predicted under real conditions. Such a simulation can be made by measuring the thermal properties and studying the temperature distribution predicted by a finite differences computer model. Measurements of adiabatic temperature rise were made using a computer-controlled adiabatic calorimeter which was designed and developed for this thesis. Conditions very close to zero heat exchange with the environment were achieved. The existence of this method made it possible to actually observe the fact that cement hydration results in boiling off of the water in such conditions. A number of additives were tried to prevent this. It was observed that waste or by-product materials such as blast furnace slag and fly ash could be used to dramatically reduced the temperature in large bodies. These materials also reacted extensively with the highly alkaline radioactive waste solution to form hydrogarnet and zeolitic material which had useful cementing properties. The conclusion was reached that a selection of blends of aluminosilicate materials can be utilized for providing the proper thermal environment for long-term geological disposal of radioactive waste

In Situ Imaging of Particle Formation and Dynamics in Reactive Material Deflagrations

Energy Technology Data Exchange (ETDEWEB)

Sullivan, Kyle T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-12-12

Reactive composites utilizing nanoparticles have been the topic of extensive research in the past two decades. The driver for this is that, as the particle size is decreased, the mixing scale between constituents is greatly reduced, which has long thought to increase the rate of chemical reaction. While a general trend of increased reactivity has been seen for metal / metal oxide, or thermite, reactive materials, some results have demonstrated diminishing returns as the particle size is further decreased. Recent results have shown that nanoparticles, which are typically aggregates of several primary particles, can undergo very rapid coalescence to form micron particles once a critical temperature is reached. Experiments on this topic to date have been performed on very small sample masses, and sometimes under vacuum; conditions which are not representative of the environment during a deflagration. In this feasibility study, a custom burn tube was used to ignite and react 100 mg powdered thermite samples in long acrylic tubes. X-ray imaging at APS Sector 32 was performed to image the particle field as a function of distance and time as the rarefied particle cloud expanded and flowed down the tube. Five different thermite formulations were investigated, Al / CuO, Al / Fe₂O₃, Al / SnO₂, Al / WO₃, and Al / Fe₂O₃, along with Al / CuO formulations with different sizes of Al particles ranging from 80 nm to approximate 10 μm. The results clearly show that the sample powder reacts and unloads into a distribution of larger micron-scale particles (~5-500 μm), which continue to react and propagate as the particle-laden stream flows down the tube. This was the first direct imaging of the particle field during a thermite deflagration, and gives significant insight into the evolution of reactants to products. Analysis of phase is currently being pursued to determine whether this method can be used to extract

Thermodynamic Analysis of Chemically Reacting Mixtures-Comparison of First and Second Order Models.

Science.gov (United States)

Pekař, Miloslav

2018-01-01

Recently, a method based on non-equilibrium continuum thermodynamics which derives thermodynamically consistent reaction rate models together with thermodynamic constraints on their parameters was analyzed using a triangular reaction scheme. The scheme was kinetically of the first order. Here, the analysis is further developed for several first and second order schemes to gain a deeper insight into the thermodynamic consistency of rate equations and relationships between chemical thermodynamic and kinetics. It is shown that the thermodynamic constraints on the so-called proper rate coefficient are usually simple sign restrictions consistent with the supposed reaction directions. Constraints on the so-called coupling rate coefficients are more complex and weaker. This means more freedom in kinetic coupling between reaction steps in a scheme, i.e., in the kinetic effects of other reactions on the rate of some reaction in a reacting system. When compared with traditional mass-action rate equations, the method allows a reduction in the number of traditional rate constants to be evaluated from data, i.e., a reduction in the dimensionality of the parameter estimation problem. This is due to identifying relationships between mass-action rate constants (relationships which also include thermodynamic equilibrium constants) which have so far been unknown.

High Efficient Enrichment and Activated Dissolution of Refractory Low Grade Rh-containing Material

Institute of Scientific and Technical Information of China (English)

WU Xiaofeng; DONG Haigang; TONG Weifeng; ZHAO Jiachun; ZENG Rui

2012-01-01

Aiming to the low-grade rhodium-containing waste materials,a new process was proposed to enrich and activate rhodium by smelting using iron oxide as a trapping agent and activator.A rhodium concentrate was obtained by the separation of base metals and precious metals.The concentrate was reacted with dilute aqua regia to obtain rhodium solution.The factors influencing the enrichment and activation effects were discussed in this paper.The results showed that the dissolution rate is greater than 99％ under the optimum conditions.In this process,the activation of rhodium was finished in the enrichment process.The iron oxide is both a trapping agent and activator,which simplifies the process and reduce the cost.

Preparation and characterisation of mixed silicon oxycarbide materials; Preparacion y caracterizacion de materiales de oxicarburo de silicio mixtos

Energy Technology Data Exchange (ETDEWEB)

Tellez, L.; Tamayo, A.; Mazo, M. A.; Rubio, F.; Rubio, J.

2010-07-01

In this work different mixed Silicon oxicarbide materials have been prepared. Si, Si-Ti, Si-Zr and Si-Al oxicarbide materials have been obtained from pyrolisis at 1000 degree centigrade and 1300 degree centigrade of the respective preceramic materials. After pyrolisis X, D and T units of the oxycarbide structure have been observed in such materials. They show the presence of Si-C and Si-O bonds in a given material. The characterization has been carried out by means of FT-IR, Raman NMR {sup 2}9Si, NMR {sup 1}3C and XRD. The formation of Si-Ti, Si-Zr and Si-Al bonds has been estimated in accordance with the decrease of the Si-O-Si wave number observed in the FT-IR spectra. Si and Si-Ti oxycarbide materials do not lead to crystallisation after pyrolisis at highest temperatures, however for Si-Zr and Si-Al oxycarbide materials different crystalline phases have been observed. All pyrolised materials present free and carbidic carbon. After pyrolisis at 1300 degree centigrade the free carbon reacts with Si-O bonds to form SiC{sub 4} groups which must be assigned to nucleus of the {beta}-SiC crystals. (Author)

The effect of physiologic aqueous solutions on the perovskite material lead-lanthanum-zirconium titanate (PLZT)

Science.gov (United States)

Foster, William J.; Meen, James K.; Fox, Donald A.

2016-01-01

Context Perovskite compounds, including Lead-Lanthanum-Zirconium Titanate (PLZT), have wide technological application because of their unique physical properties. The use of PLZT in neuro-prosthetic systems, such as retinal implants, have been discussed in a number of publications. Since inorganic lead is a retinotoxic compound that produces retinal degeneration, the long-term stability of PLZT in aqueous biological solutions must be determined. Objective We evaluated the stability and effects of prolonged immersion of a PLZT-coated crystal in a buffered balanced salt solution. Materials and Methods Scanning Electron Microscopy and Electron Dispersive Spectroscopy (EDS) using a JEOL JSM 5410 microscope equipped with EDS were utilized to evaluate the samples before and after prolonged immersion. Results We found that lead and other constituents of PLZT leached into the surrounding aqueous medium. Discussion By comparing the unit cell of PLZT with that of CaTiO3, which has been found to react with aqueous fluids, Lead is in the same site in PLZT as Ca is in CaTiO3. It is thus reasonable that PLZT will react with aqueous solutions. Conclusion The results suggest that PLZT must either be coated with a protective layer or is not appropriate for long-term in vivo or in vitro biological applications. PMID:22697294

Identification of cross-reacting T-cell epitopes in structural and non-structural proteins of swine and pandemic H1N1 influenza A virus strains in pigs

DEFF Research Database (Denmark)

Baratelli, Massimiliano; Pedersen, Lasse Eggers; Trebbien, Ramona

2017-01-01

Heterologous protection against swine influenza viruses (SwIVs) of different lineages is an important concern for the pig industry. Cross-protection between 'avian-like' H1N1 and 2009 pandemic H1N1 lineages has been observed previously, indicating the involvement of cross-reacting T-cells. Here...

Coating materials

International Nuclear Information System (INIS)

Ozeki, Takao; Kimura, Tadashi; Kobayashi, Juichi; Maeda, Yutaka; Nakamoto, Hideo.

1969-01-01

A non-solvent type coating material composition is provided which can be hardened by irradiation with active energy, particularly electron beams, using a composition which contains 10%-100% of a radically polymerizable low molecular compound (A), (hereafter called an oligomer), having at least two vinyl radicals in one molecule. These compositions have a high degree of polymerization and characteristics equivalent to thermosetting acrylic or amino alkyd resin. The oligomer (A) is produced by reacting an epoxy-containing vinyl monomer with saturated polycarboxylic acids or anhydrides. In one embodiment, 146 parts by weight of adipic acid and 280 parts of glycidyl methacrylate ester undergo addition reaction in the presence of a polymerization-inhibitor and a catalyst at 90 0 C for 6 hours to produce an oligomer having a fiberous divinyl construction. The coating composition utilizes this oligomer in the forms of (I-1), a whole oligomer; (I-2), 0%-90% of this oligomer and 90%-10% of a vinyl monomer containing at least 30% of (meth) acrylic monomer; (I-3), 10%-90% of such oligomer and 90%-10% of other monomers containing at least two vinyl radicals in one molecule; (I-4), a mixture of (I-2) and (I-3) in proportion of 1/9 to 9/1, and (I-5), above four compositions each containing 50% or less unsaturated polyester or drying oil having 500-5,000 molecules or a drying oil-modified alkyd resin having 500-5,000 molecules. Four examples are given. (Iwakiri, K.)

Entropy Filtered Density Function for Large Eddy Simulation of Turbulent Reacting Flows

Science.gov (United States)

Safari, Mehdi

Analysis of local entropy generation is an effective means to optimize the performance of energy and combustion systems by minimizing the irreversibilities in transport processes. Large eddy simulation (LES) is employed to describe entropy transport and generation in turbulent reacting flows. The entropy transport equation in LES contains several unclosed terms. These are the subgrid scale (SGS) entropy flux and entropy generation caused by irreversible processes: heat conduction, mass diffusion, chemical reaction and viscous dissipation. The SGS effects are taken into account using a novel methodology based on the filtered density function (FDF). This methodology, entitled entropy FDF (En-FDF), is developed and utilized in the form of joint entropy-velocity-scalar-turbulent frequency FDF and the marginal scalar-entropy FDF, both of which contain the chemical reaction effects in a closed form. The former constitutes the most comprehensive form of the En-FDF and provides closure for all the unclosed filtered moments. This methodology is applied for LES of a turbulent shear layer involving transport of passive scalars. Predictions show favor- able agreements with the data generated by direct numerical simulation (DNS) of the same layer. The marginal En-FDF accounts for entropy generation effects as well as scalar and entropy statistics. This methodology is applied to a turbulent nonpremixed jet flame (Sandia Flame D) and predictions are validated against experimental data. In both flows, sources of irreversibility are predicted and analyzed.

Ultrasensitive immunoradiometric assay for chorionic gonadotropin which does not cross-react with luteinizing hormone nor free β chain of hCG and which detects hCG in blood of non-pregnant humans

International Nuclear Information System (INIS)

Griffin, J.; Odell, W.D.

1987-01-01

A sensitive, non-competitive, two-monoclonal antibody, sandwich-type or immunoradiometric assay has been developed for human chorionic gonadotropin (hCG) which shows no cross-reaction with the free β chain of hCG nor with human luteinizing hormone (LH). In the assay procedure, two, highly selected monoclonal antibodies reacted in solution with hCG to be quantified. One antibody was covalently conjugated to biotin. This antibody was specific for the β subunit of hCG, and showed no reaction with LH nor the α subunit. The second antibody was labelled with 125 I and was specific for intact hCG and LH, showing no cross-reaction with βhCG nor the α subunit. The separation system was a polystyrene ball conjugated with biotin. This ball bound via an avidin bridge the monoclonal 'sandwich' containing hCG. Counts per minute bound to the ball were directly proportional to the amount of hCG present. The assay was specific for whole hCG and showed no reaction with βhCG, βLH, intact LH nor the free α subunit. Sensitivity was adequate to detect 'hCG-like' material in all post menopausal women and, when single samples were obtained, in over 2/3 of normal men. When multiple samples were obtained, 'hCG-like' material was detectable in all eugonadal adults studied. 27 refs.; 4 figs.; 1 table

Immunolocalization of Schistosoma mansoni and Schistosoma haematobium antigens reacting with their Egyptian snail vectors.

Science.gov (United States)

El-Dafrawy, Shadia M; Mohamed, Amira H; Hammam, Olfat A; Rabia, Ibrahim

2007-12-01

The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails.

Investigating the stability of cathode materials for rechargeable lithium ion batteries

Science.gov (United States)

Huang, Yiqing

Lithium ion batteries are widely used in portable electronic devices and electric vehicles. However, safety is one of the most important issues for the Li-ion batteries' use. Some cathode materials, such as LiCoO 2, are thermally unstable in the charged state. Upon decomposition these cathode materials release O2, which could react with organic electrolyte, leading to a thermal runaway. Thus understanding the stability of the cathode materials is critical to the safety of lithium ion batteries. Olivine-type LiMnPO4 is a promising cathode material for lithium ion batteries because of its high energy density. We have revealed the critical role of carbon in the stability and thermal behaviour of olivine MnPO 4 obtained by chemical delithiation of LiMnPO4. (Li)MnPO 4 samples with various particle sizes and carbon contents were studied. Carbon-free LiMnPO4 obtained by solid state synthesis in O 2 becomes amorphous upon delithiation. Small amounts of carbon (0.3 wt.%) help to stabilize the olivine structure, so that completely delithiated crystalline olivine MnPO4 can be obtained. Larger amount of carbon (2 wt.%) prevents full delithiation. Heating in air, O2, or N 2 results in structural disorder (cathode materials and the electrolyte. The thermal stability of electrochemically delithiated Li0.1N 0.8C0.15Al0.05O2 (NCA), FePO4 (FP), Mn0.8Fe0.2PO4 (MFP), hydrothermally synthesized VOPO4, LiVOPO4 and electrochemically lithiated Li2VOPO4 is investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis, coupled with mass spectrometry (TGA-MS). The thermal stability is found in the order: NCA< VOPO4< MFP< FP=LiVOPO4=Li2VOPO4. Sealed capsule high pressure experiments show a phase transformation of VOPO4 → HVOPO4 → H2VOPO4 when VOPO4 reacts with electrolyte (1 M LiPF6 in EC: DMC=1:1) between 200 and 300 °C. Finally, we characterize the lithium storage and release mechanism of V2O5 aerogels by x-ray photoelectron spectroscopy (XPS). We study the

MP Salsa: a finite element computer program for reacting flow problems. Part 1--theoretical development

Energy Technology Data Exchange (ETDEWEB)

Shadid, J.N.; Moffat, H.K.; Hutchinson, S.A.; Hennigan, G.L.; Devine, K.D.; Salinger, A.G.

1996-05-01

The theoretical background for the finite element computer program, MPSalsa, is presented in detail. MPSalsa is designed to solve laminar, low Mach number, two- or three-dimensional incompressible and variable density reacting fluid flows on massively parallel computers, using a Petrov-Galerkin finite element formulation. The code has the capability to solve coupled fluid flow, heat transport, multicomponent species transport, and finite-rate chemical reactions, and to solver coupled multiple Poisson or advection-diffusion- reaction equations. The program employs the CHEMKIN library to provide a rigorous treatment of multicomponent ideal gas kinetics and transport. Chemical reactions occurring in the gas phase and on surfaces are treated by calls to CHEMKIN and SURFACE CHEMKIN, respectively. The code employs unstructured meshes, using the EXODUS II finite element data base suite of programs for its input and output files. MPSalsa solves both transient and steady flows by using fully implicit time integration, an inexact Newton method and iterative solvers based on preconditioned Krylov methods as implemented in the Aztec solver library.

Compatibility of candidate structural materials with static gallium

International Nuclear Information System (INIS)

Luebbers, P.R.; Michaud, W.F.; Chopra, O.K.

1993-01-01

Scoping tests were conducted on compatibility of gallium with candidate structural materials, e.g., Type 316 SS, Inconel 625, and Nb-5 Mo-1 Zr alloy, as well as Armco iron, Nickel 270, and pure chronimum. Type 316 stainless steel is least resistant and Nb-5 Mo-1 Zr alloy is most resistant to corrosion in static gallium. At 400 degrees C, corrosion rates are ∼4.0, 0.5, and 0.03 mm/y for Type 316 SS, Inconel 625, and Nb-5 Mo-1 Zr alloy, respectively. The pure metals react rapidly with gallium. In contrast to findings in earlier studies, pure iron shows greater corrosion than does nickel. The corrosion rates at 400 degrees C are ≥90 and 17 mm/y, respectively, for Armco iron and Nickel 270. The results indicate that at temperatures up to 400 degrees C, corrosion occurs primarily by dissolution accompanied by formation of metal/gallium intermetallic compounds

Low energy electron irradiation induced carbon etching: Triggering carbon film reacting with oxygen from SiO{sub 2} substrate

Energy Technology Data Exchange (ETDEWEB)

Chen, Cheng [Institute of Nanosurface Science and Engineering (INSE), Shenzhen University, Shenzhen 518060 (China); Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Wang, Chao, E-mail: cwang367@szu.edu.cn, E-mail: dfdiao@szu.edu.cn; Diao, Dongfeng, E-mail: cwang367@szu.edu.cn, E-mail: dfdiao@szu.edu.cn [Institute of Nanosurface Science and Engineering (INSE), Shenzhen University, Shenzhen 518060 (China)

2016-08-01

We report low-energy (50–200 eV) electron irradiation induced etching of thin carbon films on a SiO{sub 2} substrate. The etching mechanism was interpreted that electron irradiation stimulated the dissociation of the carbon film and SiO{sub 2}, and then triggered the carbon film reacting with oxygen from the SiO{sub 2} substrate. A requirement for triggering the etching of the carbon film is that the incident electron penetrates through the whole carbon film, which is related to both irradiation energy and film thickness. This study provides a convenient electron-assisted etching with the precursor substrate, which sheds light on an efficient pathway to the fabrication of nanodevices and nanosurfaces.

The effect of fly ash and coconut fibre ash as cement replacement materials on cement paste strength

Science.gov (United States)

Bayuaji, R.; Kurniawan, R. W.; Yasin, A. K.; Fatoni, H. AT; Lutfi, F. M. A.

2016-04-01

Concrete is the backbone material in the construction field. The main concept of the concrete material is composed of a binder and filler. Cement, concrete main binder highlighted by environmentalists as one of the industry are not environmentally friendly because of the burning of cement raw materials in the kiln requires energy up to a temperature of 1450° C and the output air waste CO2. On the other hand, the compound content of cement that can be utilized in innovation is Calcium Hydroxide (CaOH), this compound will react with pozzolan material and produces additional strength and durability of concrete, Calcium Silicate Hydrates (CSH). The objective of this research is to explore coconut fibers ash and fly ash. This material was used as cement replacement materials on cement paste. Experimental method was used in this study. SNI-03-1974-1990 is standard used to clarify the compressive strength of cement paste at the age of 7 days. The result of this study that the optimum composition of coconut fiber ash and fly ash to substitute 30% of cement with 25% and 5% for coconut fibers ash and fly ash with similar strength if to be compared normal cement paste.

Preparation of glass-forming materials from granulated blast furnace slag

Science.gov (United States)

Alonso, M.; Sáinz, E.; Lopez, F. A.

1996-10-01

Glass precursor materials, to be used for the vitrification of hazardous wastes, have been prepared from blast furnace slag powder through a sol-gel route. The slag is initially reacted with a mixture of alcohol (ethanol or methanol) and mineral acid (HNO3 or H2SO4) to give a sol principally consisting of Si, Ca, Al, and Mg alkoxides. Gelation is carried out with variable amounts of either ammonia or water. The gelation rate can be made as fast as desired by adding excess hydrolizing agent or else by distilling the excess alcohol out of the alkoxide solution. The resulting gel is first dried at low temperature and ground. The powder thus obtained is then heat treated at several temperatures. The intermediate and final materials are characterized by thermal analysis, infrared (IR) spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and chemical analysis. From the results, the operating conditions yielding a variety of glass precursors differing in their composition are established. The method, in comparison with direct vitrification of slag, presents a number of advantages: (1) the glass precursor obtained devitrifies at higher temperatures; (2) it enables the adjustment, to a certain extent, of the chemical composition of the glass precursor; and (3) it permits recovering marketable materials at different stages of the process.

Development of low activation aluminum alloys for reacting plasma experiment

International Nuclear Information System (INIS)

Matsumoto, K.; Kawai, H.; Saida, T.; Onozuka, M.

1986-01-01

In the advanced fusion devices aiming at D-T burning, structural components such as vacuum vessels, coil casings are exposed to high energy neutrons produced by D-T reaction. From a view point of maintenability of accessibility, low radioactive structural materials are strongly preferred. The authors have developed two types of improved alloys of reduced radioactivity based on 5083 aluminum alloy: Al-Mg-Bi . Cr and Al-Mg-Cu . Zr. Both of the alloys of 50mm thickness have been proved to have excellent material properties virtually equivalent to those of 5083 alloy

Comparing Spray Characteristics from Reynolds Averaged Navier-Stokes (RANS) National Combustion Code (NCC) Calculations Against Experimental Data for a Turbulent Reacting Flow

Science.gov (United States)

Iannetti, Anthony C.; Moder, Jeffery P.

2010-01-01

Developing physics-based tools to aid in reducing harmful combustion emissions, like Nitrogen Oxides (NOx), Carbon Monoxide (CO), Unburnt Hydrocarbons (UHC s), and Sulfur Dioxides (SOx), is an important goal of aeronautics research at NASA. As part of that effort, NASA Glenn Research Center is performing a detailed assessment and validation of an in-house combustion CFD code known as the National Combustion Code (NCC) for turbulent reacting flows. To assess the current capabilities of NCC for simulating turbulent reacting flows with liquid jet fuel injection, a set of Single Swirler Lean Direct Injection (LDI) experiments performed at the University of Cincinnati was chosen as an initial validation data set. This Jet-A/air combustion experiment operates at a lean equivalence ratio of 0.75 at atmospheric pressure and has a 4 percent static pressure drop across the swirler. Detailed comparisons of NCC predictions for gas temperature and gaseous emissions (CO and NOx) against this experiment are considered in a previous work. The current paper is focused on detailed comparisons of the spray characteristics (radial profiles of drop size distribution and at several radial rakes) from NCC simulations against the experimental data. Comparisons against experimental data show that the use of the correlation for primary spray break-up implemented by Raju in the NCC produces most realistic results, but this result needs to be improved. Given the single or ten step chemical kinetics models, use of a spray size correlation gives similar, acceptable results

A review of accelerated carbonation technology in the treatment of cement-based materials and sequestration of CO2

International Nuclear Information System (INIS)

Fernandez Bertos, M.; Simons, S.J.R.; Hills, C.D.; Carey, P.J.

2004-01-01

Moist calcium silicate minerals are known to readily react with carbon dioxide (CO 2 ). The reaction products can cause rapid hardening and result in the production of monolithic materials. Today, accelerated carbonation is a developing technology, which may have potential for the treatment of wastes and contaminated soils and for the sequestration of CO 2 , an important greenhouse gas. This paper reviews recent developments in this emerging technology and provides information on the parameters that control the process. The effects of the accelerated carbonation reaction on the solid phase are discussed and future potential applications of this technology are also considered

Ion doping of surface layers in conducting electrical materials

International Nuclear Information System (INIS)

Zukowski, P.; Karwat, Cz.; Kozak, Cz. M.; Kolasik, M.; Kiszczak, K.

2009-01-01

The presented article gives basic component elements of an implanter MKPCz-99, its parameters and methods for doping surface layers of conducting electrical materials. The discussed device makes possible to dope the materials with ions of gaseous elements. At the application of cones made of solid-element sheets it is possible to perform doping with atoms that do not chemically react with the modified material. By performing voltage drop measurements with a specialized circuit between a movable testing electrode and the modified sample the dependence of transition resistance on pressure force of the testing electrode on the sample can be determined. The testing can be performed at the current passage of a determined value for surfaces modified with ions of gaseous elements or atoms of solid elements. A computer stand for switch testing makes possible to measure temperature of switch contacts and voltage drop at the contact and thereby to determine contact resistance of a switch depending on the number of switch cycles (ON-OFF). Pattern recording of current and voltage at the switch contacts and the application of an adequate computer software makes possible to determined the value of energy between fixed and moving contacts at their getting apart. In order to eliminate action of the environment onto the switch operation measurements can be performed at placing the tested switch together with the driving system in an atmosphere of noble gas like argon. (authors)

Do analysts anticipate and react to bankruptcy? Evidence

OpenAIRE

Coelho, Luís; Peixinho, Rúben

2005-01-01

Finance literature suggests that financial analysts are sophisticated agents that act as facilitators of market efficiency by releasing relevant information to the market. This paper uses a sample of four major US bankruptcies to explore if analysts are able to disclose information to the market that provides investors with material information for their investment decisions. In particular, we use a qualitative approach to analyse analysts’ reports in order to verify if these agents are ab...

Modeling study of rarefied gas effects on hypersonic reacting stagnation flows

Science.gov (United States)

Wang, Zhihui; Bao, Lin

2014-12-01

Recent development of the near space hypersonic sharp leading vehicles has raised a necessity to fast and accurately predict the aeroheating in hypersonic rarefied flows, which challenges our understanding of the aerothermodynamics and aerothermochemistry. The present flow and heat transfer problem involves complex rarefied gas effects and nonequilibrium real gas effects which are beyond the scope of the traditional prediction theory based on the continuum hypothesis and equilibrium assumption. As a typical example, it has been found that the classical Fay-Riddell equation fails to predict the stagnation point heat flux, when the flow is either rarefied or chemical nonequilibrium. In order to design a more general theory covering the rarefied reacting flow cases, an intuitive model is proposed in this paper to describe the nonequilibrium dissociation-recombination flow along the stagnation streamline towards a slightly blunted nose in hypersonic rarefied flows. Some characteristic flow parameters are introduced, and based on these parameters, an explicitly analytical bridging function is established to correct the traditional theory to accurately predict the actual aeroheating performance. It is shown that for a small size nose in medium density flows, the flow at the outer edge of the stagnation point boundary layer could be highly nonequilibrium, and the aeroheating performance is distinguished from that of the big blunt body reentry flows at high altitudes. As a result, when the rarefied gas effects and the nonequilibrium real gas effects are both significant, the classical similarity law could be questionable, and it is inadequate to directly analogize results from the classical blunt body reentry problems to the present new generation sharp-leading vehicles. In addition, the direct simulation Monte Carlo method is also employed to validate the conclusion.

Phenolic cation-exchange resin material for recovery of cesium and strontium. [Patent application

Science.gov (United States)

Ebra, M.A.; Wallace, R.M.

1982-05-05

A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear wate solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs/sup +/ and Sr/sup 2 +/ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

Some characteristics of potential backfill materials

International Nuclear Information System (INIS)

Simpson, D.R.

1983-05-01

A backfill material is one of the multiple barriers that may be involved in the disposal of nuclear waste. Such backfill should be a desiccant with the hydrous product having acceptable stability; it should sorb any released radioisotopes, and it should reseal any breached site. The backfill must also have acceptable thermal conductivity. This report presents data on the rate of hydration and the nature of the product of reaction of some candidate backfill materials with water and with brine. Thermal conductivity data is reported for both the reactants and the products. Granular MgO at 150 0 C completely hydrates in less than 10 hours. At 60 0 C and 20 0 C, such extensive hydration requires about 100 and 1000 hours, respectively. The product of the reaction is stable to more than 300 0 C. A doped discalcium silicate was less reactive and the product contains less water of crystallization than the MgO. The reaction product of dicalcium silicate is cementous, but it has low thermal stability. Bentonite readily reacts with water and expands. The reaction product has the properties of vermiculite, which indicates that magnesium ions have diffused into the bentonite structure and are not simply adsorbed on the surface. If bentonite is emplaced in a saline environment, the properties of vermiculite, the reaction product, should also be considered. The thermal conductivity of MgO, discalcium silicate, and bentonite is primarily dependent on the porosity of the sample. A slight increase in thermal conductivity was found with increased temperature, in contrast to most rocks. If the conductive data for the different materials is equated to the same porosity, MgO has the superior thermal conductivity compared to bentonite or discalcium silicate

Durability of concrete materials in high-magnesium brine

International Nuclear Information System (INIS)

Wakeley, L.D.; Poole, T.S.; Burkes, J.P.

1994-03-01

Cement pastes and mortars representing 11 combinations of candidate concrete materials were cast in the laboratory and monitored for susceptibility to chemical deterioration in high-magnesium brine. Mixtures were selected to include materials included in the current leading candidate concrete for seals at the Waste Isolation Pilot Plant (WIPP). Some materials were included in the experimental matrix to answer questions that had arisen during study of the concrete used for construction of the liner of the WIPP waste-handling shaft. Mixture combinations compared Class C and Class F fly ashes, presence or absence of an expansive component, and presence or absence of salt as a mixture component. Experimental conditions exposed the pastes and mortars to extreme conditions, those being very high levels of Mg ion and an effectively unlimited supply of brine. All pastes and mortars showed deterioration with brine exposure. In general, mortars deteriorated more extensively than the corresponding pastes. Two-inch cube specimens of mortar were not uniformly deteriorated, but showed obvious zoning even after a year in the brine, with a relatively unreacted zone remaining at the center of each cube. Loss of calcium from the calcium hydroxide of paste/aggregate interfaces caused measurable strength loss in the reacted zone comprising the outer portion of every mortar specimen. The current candidate mass concrete for WIPP seals includes salt as an initial component, and has a relatively closed initial microstructure. Both of these features contribute to its suitability for use in large placements within the Salado Formation

Microhardness, strength and strain field characterization of self-reacting friction stir and plug welds of dissimilar aluminum alloys

Science.gov (United States)

Horton, Karla Renee

Friction stir welding (FSW) is a solid state welding process with potential advantages for aerospace and automotive industries dealing with light alloys. Self-reacting friction stir welding (SR-FSW) is one variation of the FSW process being developed at the National Aeronautics and Space Administration (NASA) for use in the fabrication of propellant tanks. Friction plug welding is used to seal the exit hole that remains in a circumferential SR-FSW. This work reports on material properties and strain patterns developed in a SR-FSW with a friction plug weld. Specifically, this study examines the behavior of a SR-FSW formed between an AA2014-T6 plate on the advancing side and an AA2219-T87 plate on the retreating side and a SR-FSW (AA2014-T6 to AA2219-T87) with a 2219-T87 plug weld. This study presents the results of a characterization of the micro-hardness, joint strength, and strain field characterization of SR-FSW and FPW joints tested at room temperature and cryogenic temperatures. The initial weld microstructure analysis showed a nugget region with fine grains and a displaced weld seam from the advancing side past the thermo-mechanical affected zone (TMAZ) into the nugget region. The displaced material shared the same hardness as the parent material. Dynamic recrystallization was observed in the SR-FSW zone and the displaced weld seam region. The welds revealed a fine grain structure in the SR-FSW zone with a sharp demarcation seen on the advancing side and fairly diffuse flow observed on the retreating side. The parent material hardness is 145 HV700g with a drop in hardness starting at the HAZ to 130 HV700g. The hardness further drops in the TMAZ to118 HV700g with an increase representing a dispersed interface of AA2014-T6 material to 135 HV700g. The hardness then drops significantly within the nugget region to 85 HV700g followed by an increase through the retreating side TMAZ into the HAZ to 135 HV 700g. There was a sharp increase in the hardness value within

Comparison of PDF and Moment Closure Methods in the Modeling of Turbulent Reacting Flows

Science.gov (United States)

Norris, Andrew T.; Hsu, Andrew T.

1994-01-01

In modeling turbulent reactive flows, Probability Density Function (PDF) methods have an advantage over the more traditional moment closure schemes in that the PDF formulation treats the chemical reaction source terms exactly, while moment closure methods are required to model the mean reaction rate. The common model used is the laminar chemistry approximation, where the effects of turbulence on the reaction are assumed negligible. For flows with low turbulence levels and fast chemistry, the difference between the two methods can be expected to be small. However for flows with finite rate chemistry and high turbulence levels, significant errors can be expected in the moment closure method. In this paper, the ability of the PDF method and the moment closure scheme to accurately model a turbulent reacting flow is tested. To accomplish this, both schemes were used to model a CO/H2/N2- air piloted diffusion flame near extinction. Identical thermochemistry, turbulence models, initial conditions and boundary conditions are employed to ensure a consistent comparison can be made. The results of the two methods are compared to experimental data as well as to each other. The comparison reveals that the PDF method provides good agreement with the experimental data, while the moment closure scheme incorrectly shows a broad, laminar-like flame structure.

The interaction of iodine with organic material in containment

Energy Technology Data Exchange (ETDEWEB)

Wren, J C; Ball, J M; Glown, G A; Portmann, R; Sanipelli, G G [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

1996-12-01

Organic impurities in containment water, originating from various painted structural surfaces and organic containment materials, could have a significant impact on iodine volatility following an accident. A research program has been designed to determine the impact of organic impurities on iodine volatility under accident conditions. The program consists of experimental, literature and modelling studies on the radiolysis or organic compounds in the aqueous phase, thermal and radiolytic formation and decomposition of organic iodides, dissolution of organic solvents from various painted surfaces into the aqueous phase, and iodine deposition on painted surfaces. The experimental studies consist of bench-scale `separate effects` tests as well as intermediate-scale `integrated effects` in the Radioiodine Test facility. The studies have shown that organic impurities will be found in containment water, arising from the dissolution of organic compounds from various surface paints and that these compounds can potentially have a significant impact on iodine volatility following an accident. The main impact of surface paints will occur through aqueous-phase reactions of the organic compounds that they release to the aqueous phase. Under the radiation conditions expected during an accident, these compounds will react to reduce the pH and dissolved oxygen concentration, consequently increasing the formation of I{sub 2} from I{sup -} that is present in the sump. It appears that the rates of these processes may be controlled by the dissolution kinetics of the organic compounds from the surface coatings. Moreover, the organic compounds may also react thermally and radiolytically with I{sub 2} to form organic iodides in the aqueous phase. Our studies have shown that the formation of organic iodides from soluble organics such as ketones, alcohols and phenols may have more impact on the total iodine volatility than the formation of CH{sub 3}I. (author) 13 figs., 2 tabs., 19 refs.

The interaction of iodine with organic material in containment

International Nuclear Information System (INIS)

Wren, J.C.; Ball, J.M.; Glown, G.A.; Portmann, R.; Sanipelli, G.G.

1996-01-01

Organic impurities in containment water, originating from various painted structural surfaces and organic containment materials, could have a significant impact on iodine volatility following an accident. A research program at the Whiteshell Laboratories of AECL has been designed to determine the impact of organic impurities on iodine volatility under accident conditions. The program consists of experimental, literature and modelling studies on the radiolysis or organic compounds in the aqueous phase, thermal and radiolytic formation and decomposition of organic iodides, dissolution of organic solvents from various painted surfaces into the aqueous phase, and iodine deposition on painted surfaces. The experimental studies consist of bench-scale 'separate effects' tests as well as intermediate-scale 'integrated effects' in the Radioiodine Test facility. The studies have shown that organic impurities will be found in containment water, arising from the dissolution of organic compounds from various surface paints and that these compounds can potentially have a significant impact on iodine volatility following an accident. The main impact of surface paints will occur through aqueous-phase reactions of the organic compounds that they release to the aqueous phase. Under the radiation conditions expected during an accident, these compounds will react to reduce the pH and dissolved oxygen concentration, consequently increasing the formation of I 2 from I - that is present in the sump. It appears that the rates of these processes may be controlled by the dissolution kinetics of the organic compounds from the surface coatings. Moreover, the organic compounds may also react thermally and radiolytically with I 2 to form organic iodides in the aqueous phase. Our studies have shown that the formation of organic iodides from soluble organics such as ketones, alcohols and phenols may have more impact on the total iodine volatility than the formation of CH 3 I. (author) 13 figs., 2

Edaravone, a potent free radical scavenger, reacts with peroxynitrite to produce predominantly 4-NO-edaravone.

Science.gov (United States)

Fujisawa, Akio; Yamamoto, Yorihiro

2016-05-01

3-Methyl-1-phenyl-2-pyrazolin-5-one (edaravone) is used in clinical treatment of acute brain infarction to rescue the penumbra, based on its ability to prevent lipid peroxidation by scavenging lipid peroxyl radicals. Here, we show that edaravone also reacts with peroxynitrite to yield 4-NO-edaravone as the major product and 4-NO2-edaravone as a minor product. We observed little formation of 3-methyl-1-phenyl-2-pyrazolin-4,5-dione (4-oxoedaravone) and its hydrate, 2-oxo-3-(phenylhydrazono)butanoic acid, which are the major free radical-induced oxidation products of edaravone, suggesting that free radicals are not involved in the reaction with peroxynitrite. The reaction of peroxynitrite with edaravone is approximately 30-fold greater than with uric acid, a physiological peroxynitrite scavenger (reaction rate k = 1.5 × 10 (4)  M(-1) s(-1) vs. 480 M(-1) s(-1)). These results suggest that edaravone functions therapeutically as a scavenger of peroxynitrite as well as lipid peroxyl radicals, which is consistent with a report that edaravone treatment reduced levels of 3-nitrotyrosine in the cerebrospinal fluid of patients with amyotrophic lateral sclerosis.

3D simulation of polyurethane foam injection and reacting mold flow in a complex geometry

Science.gov (United States)

Özdemir, İ. Bedii; Akar, Fırat

2018-05-01

The aim of the present work is to develop a flow model which can be used to determine the paths of the polyurethane foam in the mold filling process of a refrigerator cabinet so that improvements in the distribution and the size of the venting holes can be achieved without the expensive prototyping and experiments. For this purpose, the multi-component, two-phase chemically reacting flow is described by Navier Stokes and 12 scalar transport equations. The air and the multi-component foam zones are separated by an interface, which moves only with advection since the mass diffusion of species are set zero in the air zone. The inverse density, viscosity and other diffusion coefficients are calculated by a mass fraction weighted average of the corresponding temperature-dependent values of all species. Simulations are performed in a real refrigerator geometry, are able to reveal the problematical zones where air bubbles and voids trapped in the solidified foam are expected to occur. Furthermore, the approach proves itself as a reliable design tool to use in deciding the locations of air vents and sizing the channel dimensions.

Dissociative diffusion mechanism in vacancy-rich materials according to mass action kinetics

Directory of Open Access Journals (Sweden)

N. J. Biderman

2016-05-01

Full Text Available Two sets of diffusion-reaction numerical simulations using a finite difference method (FDM were conducted to investigate fast impurity diffusion via interstitial sites in vacancy-rich materials such as Cu(In,GaSe2 (CIGS and Cu2ZnSn(S, Se4 (CZTSSe or CZTS via the dissociative diffusion mechanism where the interstitial diffuser ultimately reacts with a vacancy to produce a substitutional. The first set of simulations extends the standard interstitial-limited dissociative diffusion theory to vacancy-rich material conditions where vacancies are annihilated in large amounts, introducing non-equilibrium vacancy concentration profiles. The second simulation set explores the vacancy-limited dissociative diffusion where impurity incorporation increases the equilibrium vacancy concentration. In addition to diffusion profiles of varying concentrations and shapes that were obtained in all simulations, some of the profiles can be fitted with the constant- and limited-source solutions of Fick’s second law despite the non-equilibrium condition induced by the interstitial-vacancy reaction. The first set of simulations reveals that the dissociative diffusion coefficient in vacancy-rich materials is inversely proportional to the initial vacancy concentration. In the second set of numerical simulations, impurity-induced changes in the vacancy concentration lead to distinctive diffusion profile shapes. The simulation results are also compared with published data of impurity diffusion in CIGS. According to the characteristic properties of diffusion profiles from the two set of simulations, experimental detection of the dissociative diffusion mechanism in vacancy-rich materials may be possible.

Non-equilibrium plasma kinetics of reacting CO: an improved state to state approach

Science.gov (United States)

Pietanza, L. D.; Colonna, G.; Capitelli, M.

2017-12-01

Non-equilibrium plasma kinetics of reacting CO for conditions typically met in microwave discharges have been developed based on the coupling of excited state kinetics and the Boltzmann equation for the electron energy distribution function (EEDF). Particular attention is given to the insertion in the vibrational kinetics of a complete set of electron molecule resonant processes linking the whole vibrational ladder of the CO molecule, as well as to the role of Boudouard reaction, i.e. the process of forming CO2 by two vibrationally excited CO molecules, in shaping the vibrational distribution of CO and promoting reaction channels assisted by vibrational excitation (pure vibrational mechanisms, PVM). PVM mechanisms can become competitive with electron impact dissociation processes (DEM) in the activation of CO. A case study reproducing the conditions of a microwave discharge has been considered following the coupled kinetics also in the post discharge conditions. Results include the evolution of EEDF in discharge and post discharge conditions highlighting the role of superelastic vibrational and electronic collisions in shaping the EEDF. Moreover, PVM rate coefficients and DEM ones are studied as a function of gas temperature, showing a non-Arrhenius behavior, i.e. the rate coefficients increase with decreasing gas temperature as a result of a vibrational-vibrational (V-V) pumping up mechanism able to form plateaux in the vibrational distribution function. The accuracy of the results is discussed in particular in connection to the present knowledge of the activation energy of the Boudouard process.

What is the role corporate social responsability (CSR) in society in the perspective of Millennials and how do they react to CSR practices as consumers?

OpenAIRE

Barbeiro, Sofia

2016-01-01

As it grows older, the Millennial generation is gaining relevance for companies, especially when considering their demands and choices as consumers. But what is Millennials’ opinion with regard to Corporate Social Responsibility (CSR)? And how does the Millennial generation react to CSR initiatives by companies? Since CSR is gaining more importance nowadays, these are the main questions addressed by the present research. Based on primary data collected via semi-structured interviews and an on...

Nano-Aluminum Reaction with Nitrogen in the Burn Front of Oxygen-Free Energetic Materials

International Nuclear Information System (INIS)

Tappan, B. C.; Son, S. F.; Moore, D. S.

2006-01-01

Nano-particulate aluminum metal was added to the high nitrogen energetic material triaminoguanidium azotetrazolate (TAGzT) in order to determine the effects on decomposition behavior. Standard safety testing (sensitivity to impact, spark and friction) are reported and show that the addition of nano-Al actually decreases the sensitivity of the pure TAGzT. Thermo-equilibrium calculations (Cheetah) indicate that the all of the Al reacts to form AlN in TAGzT decomposition, and the calculated specific impulses are reported. T-Jump/FTIR spectroscopy was performed on the neat TAGzT. Emission spectra were collected to determine the temperature of AlN formation in combustion. Burning rates were also collected, and the effects of nano-Al on rates are discussed

Modeling reacting gases and aftertreatment devices for internal combustion engines

Science.gov (United States)

Depcik, Christopher David

As more emphasis is placed worldwide on reducing greenhouse gas emissions, automobile manufacturers have to create more efficient engines. Simultaneously, legislative agencies want these engines to produce fewer problematic emissions such as nitrogen oxides and particulate matter. In response, newer combustion methods, like homogeneous charge compression ignition and fuel cells, are being researched alongside the old standard of efficiency, the compression ignition or diesel engine. These newer technologies present a number of benefits but still have significant challenges to overcome. As a result, renewed interest has risen in making diesel engines cleaner. The key to cleaning up the diesel engine is the placement of aftertreatment devices in the exhaust. These devices have shown great potential in reducing emission levels below regulatory levels while still allowing for increased fuel economy versus a gasoline engine. However, these devices are subject to many flow control issues. While experimental evaluation of these devices helps to understand these issues better, it is impossible to solve the problem through experimentation alone because of time and cost constraints. Because of this, accurate models are needed in conjunction with the experimental work. In this dissertation, the author examines the entire exhaust system including reacting gas dynamics and aftertreatment devices, and develops a complete numerical model for it. The author begins by analyzing the current one-dimensional gas-dynamics simulation models used for internal combustion engine simulations. It appears that more accurate and faster numerical method is available, in particular, those developed in aeronautical engineering, and the author successfully implements one for the exhaust system. The author then develops a comprehensive literature search to better understand the aftertreatment devices. A number of these devices require a secondary injection of fuel or reductant in the exhaust stream

Effective bending strain estimated from I c test results of a D-shaped Nb3Al CICC coil fabricated with a react-and-wind process for the National Centralized Tokamak

International Nuclear Information System (INIS)

Ando, T.; Kizu, K.; Miura, Y.M.; Tsuchiya, K.; Matsukawa, M.; Tamai, H.; Ishida, S.; Koizumi, N.; Okuno, K.

2005-01-01

Japan National Centralized Tokamak (NCT) is a superconducting tokamak proposed as a modification to JT-60U. As part of the R and D for the National Centralized Tokamak, a two-turn, approximately 2 m tall, D-shaped Nb 3 Al coil was wound and tested using a full-size cable-in-conduit conductor (CICC). The Nb 3 Al cable-in-conductor was bent following the heat treatment reaction with a maximum bending strain of 0.4% to simulate the react-and-wind fabrication. The comparison of the coil performance to the measured strand data shows that the effective axial strain of the conductor strands is essentially zero despite the 0.4% bending strain of the conductor. This suggests that the strands in the cable slipped relatively to each other during bending of the conduit, thus reducing the effective strain transmitted to the strands. This result is very encouraging for the low-cost fabrication of high-current-density fusion coils using the react-and-wind method

An Overview of Materials Structures for Extreme Environments Efforts for 2015 SBIR Phases I and II

Science.gov (United States)

Nguyen, Hung D.; Steele, Gynelle C.

2017-01-01

Technological innovation is the overall focus of NASA's Small Business Innovation Research (SBIR) program. The program invests in the development of innovative concepts and technologies to help NASA's mission directorates address critical research and development needs for Agency projects. This report highlights innovative SBIR 2015 Phase I and II projects that specifically address areas in Materials and Structures for Extreme Environments, one of six core competencies at NASA Glenn Research Center. Each article describes an innovation, defines its technical objective, and highlights NASA applications as well as commercial and industrial applications. Ten technologies are featured: metamaterials-inspired aerospace structures, metallic joining to advanced ceramic composites, multifunctional polyolefin matrix composite structures, integrated reacting fluid dynamics and predictive materials degradation models for propulsion system conditions, lightweight inflatable structural airlock (LISA), copolymer materials for fused deposition modeling 3-D printing of nonstandard plastics, Type II strained layer superlattice materials development for space-based focal plane array applications, hydrogenous polymer-regolith composites for radiation-shielding materials, a ceramic matrix composite environmental barrier coating durability model, and advanced composite truss printing for large solar array structures. This report serves as an opportunity for NASA engineers, researchers, program managers, and other personnel to learn about innovations in this technology area as well as possibilities for collaboration with innovative small businesses that could benefit NASA programs and projects.

Field-Flow Fractionation of Carbon Nanotubes and Related Materials

Energy Technology Data Exchange (ETDEWEB)

John P. Selegue

2011-11-17

During the grant period, we carried out FFF studies of carbonaceous soot, single-walled and multi-walled carbon nanotubes, carbon nano-onions and polyoxometallates. FFF alone does not provide enough information to fully characterize samples, so our suite of characterization techniques grew to include light scattering (especially Photon Correlation Spectroscopy), scanning and transmission electron microscopy, thermogravimetric analysis and spectroscopic methods. We developed convenient techniques to deposit and examine minute FFF fractions by electron microscopy. In collaboration with Arthur Cammers (University of Kentucky), we used Flow Field-Flow Fractionation (Fl-FFF) to monitor the solution-phase growth of keplerates, a class of polyoxometallate (POM) nanoparticles. We monitored the evolution of Mo-POM nanostructures over the course of weeks by by using flow field-flow fractionation and corroborated the nanoparticle structures by using transmission electron microscopy (TEM). Total molybdenum in the solution and precipitate phases was monitored by using inductively coupled plasma analyses, and total Mo-POM concentration by following the UV-visible spectra of the solution phase. We observe crystallization-driven formation of (Mo132) keplerate and solution phase-driven evolution of structurally related nanoscopic species (3-60 nm). FFF analyses of other classes of materials were less successful. Attempts to analyze platelets of layered materials, including exfoliated graphite (graphene) and TaS2 and MoS2, were disappointing. We were not able to optimize flow conditions for the layered materials. The metal sulfides react with the aqueous carrier liquid and settle out of suspension quickly because of their high density.

Numerical Simulations of Two-Phase Reacting Flow in a Single-Element Lean Direct Injection (LDI) Combustor Using NCC

Science.gov (United States)

Liu, Nan-Suey; Shih, Tsan-Hsing; Wey, C. Thomas

2011-01-01

A series of numerical simulations of Jet-A spray reacting flow in a single-element lean direct injection (LDI) combustor have been conducted by using the National Combustion Code (NCC). The simulations have been carried out using the time filtered Navier-Stokes (TFNS) approach ranging from the steady Reynolds-averaged Navier-Stokes (RANS), unsteady RANS (URANS), to the dynamic flow structure simulation (DFS). The sub-grid model employed for turbulent mixing and combustion includes the well-mixed model, the linear eddy mixing (LEM) model, and the filtered mass density function (FDF/PDF) model. The starting condition of the injected liquid spray is specified via empirical droplet size correlation, and a five-species single-step global reduced mechanism is employed for fuel chemistry. All the calculations use the same grid whose resolution is of the RANS type. Comparisons of results from various models are presented.

Excess antibody immunoassays for rat glandular kallikreins. Measurement of kallikrein from different organs in the presence of cross-reacting antigens

International Nuclear Information System (INIS)

Johansen, L.; Oerstavik, T.B.; Holck, M.; Nustad, K.

1983-01-01

An immunoradiometric assay has previously been developed for measurement of rat glandular kallikrein. In the present paper, further studies on the specificity and sensitivity of the method are described. Problems of interference of immunologically cross-reacting antigens were overcome by proper preabsorption of the antibody. A method was thus established in which enzymatic activity of the immunoreactive kallikrein could be measured even in the presence of enzymes sharing immunological determinants and substrate specificity with kallikrein. Two variants of the immunoradiometric assay have been evaluated. A simplified version with simultaneous addition of all reagents gave results equal to those obtained in the original assay. A further modification with delayed addition of the solid-phase antibody, gave considerable improvement in assay sensitivity. (Auth.)

Adsorption and revaporisation studies of thin iodine oxide and CsI aerosol deposits from containment surface materials in LWRs

Energy Technology Data Exchange (ETDEWEB)

Tietze, S.; Foreman, M.; Ekberg, C. [Chalmers Univ. of Technology, Goeteborg (Sweden); Kaerkelae, T.; Auvinen, A.; Tapper, U.; Jokiniemi, J. [VTT Technical Research Centre of Finland, Espoo (Finland)

2013-07-15

During a severe nuclear accident released fission and radiolysis products can react with each other to form new species which might contribute to the volatile source term. Iodine will be released from UO2 fuel mainly in form as CsI aerosol particles and elemental iodine. Elemental iodine can react in gaseous phase with ozone to form solid iodine oxide aerosol particles (IOx). Within the AIAS-2 (Adsorption of Iodine Aerosols on Surfaces) project the interactions of IOx and CsI aerosols with common containment surface materials was investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS. Non-radioactive and {sup 131}I labelled aerosols were produced from a KI solution and ozone with a new facility designed and built at VTT Technical Research Centre of Finland. CsI aerosols were produced from a CsI solution with the same facility. A monolayer of the aerosols was deposited on the surfaces. The deposits were analysed with microscopic and spectroscopic measurement techniques to identify the chemical form of the deposits on the surfaces to identify if a chemical conversion on the different surface materials had occured. The revaporisation behaviour of the deposited aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 with a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The decomposition effect of the radiolysis product carbon monoxide was tested on IOx aerosols deposited on a glass fibre filter. Iodine oxide particles were produced at 50 deg. C, 100 deg. C and 120 deg. C and deposited on filter samples in order to study the chemical

Adsorption and revaporisation studies of thin iodine oxide and CsI aerosol deposits from containment surface materials in LWRs

International Nuclear Information System (INIS)

Tietze, S.; Foreman, M.; Ekberg, C.; Kaerkelae, T.; Auvinen, A.; Tapper, U.; Jokiniemi, J.

2013-07-01

During a severe nuclear accident released fission and radiolysis products can react with each other to form new species which might contribute to the volatile source term. Iodine will be released from UO2 fuel mainly in form as CsI aerosol particles and elemental iodine. Elemental iodine can react in gaseous phase with ozone to form solid iodine oxide aerosol particles (IOx). Within the AIAS-2 (Adsorption of Iodine Aerosols on Surfaces) project the interactions of IOx and CsI aerosols with common containment surface materials was investigated. Common surface materials in Swedish and Finnish LWRs are Teknopox Aqua V A paint films and metal surfaces such as Cu, Zn, Al and SS. Non-radioactive and 131 I labelled aerosols were produced from a KI solution and ozone with a new facility designed and built at VTT Technical Research Centre of Finland. CsI aerosols were produced from a CsI solution with the same facility. A monolayer of the aerosols was deposited on the surfaces. The deposits were analysed with microscopic and spectroscopic measurement techniques to identify the chemical form of the deposits on the surfaces to identify if a chemical conversion on the different surface materials had occured. The revaporisation behaviour of the deposited aerosol particles from the different surface materials was studied under the influence of heat, humidity and gamma irradiation at Chalmers University of Technology, Sweden. Studies on the effects of humidity were performed using the FOMICAG facility, while heat and irradiation experiments were performed in a thermostated heating block and with a gammacell 22 with a dose rate of 14 kGy/h. The revaporisation losses were measured using a HPGe detector. The decomposition effect of the radiolysis product carbon monoxide was tested on IOx aerosols deposited on a glass fibre filter. Iodine oxide particles were produced at 50 deg. C, 100 deg. C and 120 deg. C and deposited on filter samples in order to study the chemical speciation of

Preparation and Characterization of Cathode Materials for Lithium-Oxygen Batteries

DEFF Research Database (Denmark)

Storm, Mie Møller

A possible future battery type is the Li-air battery which theoretically has the potential of reaching gravimetric energy densities close to those of gasoline. The Li-airbattery is discharged by the reaction of Li-ions and oxygen, drawn from the air, reacting at the battery cathode to form Li2O2....... The type of cathode material affects the battery discharge capacity and charging potential and with a carbon based cathode many questions are still unanswered. The focus of this Ph.D. project has been the synthesis of reduced graphene oxide as well as the investigation of the effect of reduced graphene...... the discharge capacity of the battery as well as the charging potential. In situ X-ray diffraction studies on carbon black cathodes in a capillary battery showed the formation of crystalline Li2O2 on the first discharge cycle, the intensity of Li2O2 on the second discharge cycle was however diminished...

Transportation of Hazardous Evidentiary Material.

Energy Technology Data Exchange (ETDEWEB)

Osborn, Douglas.

2005-06-01

This document describes the specimen and transportation containers currently available for use with hazardous and infectious materials. A detailed comparison of advantages, disadvantages, and costs of the different technologies is included. Short- and long-term recommendations are also provided.3 DraftDraftDraftExecutive SummaryThe Federal Bureau of Investigation's Hazardous Materials Response Unit currently has hazardous material transport containers for shipping 1-quart paint cans and small amounts of contaminated forensic evidence, but the containers may not be able to maintain their integrity under accident conditions or for some types of hazardous materials. This report provides guidance and recommendations on the availability of packages for the safe and secure transport of evidence consisting of or contaminated with hazardous chemicals or infectious materials. Only non-bulk containers were considered because these are appropriate for transport on small aircraft. This report will addresses packaging and transportation concerns for Hazardous Classes 3, 4, 5, 6, 8, and 9 materials. If the evidence is known or suspected of belonging to one of these Hazardous Classes, it must be packaged in accordance with the provisions of 49 CFR Part 173. The anthrax scare of several years ago, and less well publicized incidents involving unknown and uncharacterized substances, has required that suspicious substances be sent to appropriate analytical laboratories for analysis and characterization. Transportation of potentially hazardous or infectious material to an appropriate analytical laboratory requires transport containers that maintain both the biological and chemical integrity of the substance in question. As a rule, only relatively small quantities will be available for analysis. Appropriate transportation packaging is needed that will maintain the integrity of the substance, will not allow biological alteration, will not react chemically with the substance being

What is the role of Corporate Social Responsibility (CSR) in society in the perspective of Millennials and how do they react to CSR practices as consumers?

OpenAIRE

Barbeiro, Sofia Pereira

2016-01-01

As it grows older, the Millennial generation is gaining relevance for companies, especially when considering their demands and choices as consumers. But what is Millennials’ opinion with regard to Corporate Social Responsibility (CSR)? And how does the Millennial generation react to CSR initiatives by companies? Since CSR is gaining more importance nowadays, these are the main questions addressed by the present research. Based on primary data collected via semi-structured interviews and an on...

Interaction of actinides with natural microporous materials: a review

International Nuclear Information System (INIS)

Misaelides, P.; Godelitsas, A.

1998-01-01

Natural microporous materials include several types of minerals such as zeolites, clay minerals, micas, iron- and manganese-oxides/hydroxides/oxyhydroxides present in various geological environments and soil formations. The transport of the actinide elements in the environment is mainly performed through aquatic pathways (streams, rivers, underground waters) and their mobility is strongly related to the interaction of their dissolved species with geological materials and especially with the highly sorptive microporous minerals. The existing studies mainly concern the sorption of Th, U, Np, Pu and Am from aqueous media by clay minerals and zeolites as well as the determination of the corresponding chemical processes taking place at the mineral-water interface. The investigation techniques also include advanced spectroscopic methods such as Extended X-ray Absorption Fine Structure Spectroscopy (EXAFS), Rutherford Backscattered Spectroscopy (RBS), X-ray Photoelectron Spectroscopy (XPS) and Raman Spectroscopy. These techniques significantly contribute to the characterization of the reacted mineral surfaces and to the explanation of the structural and compositional characteristics of the sorbed actinide species. Theoretical models regarding the aqueous chemistry and speciation of the actinides have also been developed aiming the elucidation of the complex actinide sorption mechanisms. Finally, this contribution also includes some recently obtained data concerning the interaction of actinides with todorokite (a naturally occurring microporous manganese-oxide of technological importance) and granitic micas (biotite) correlated with the nuclear waste disposal in geological formations

Numerical study on non-locally reacting behavior of nacelle liners incorporating drainage slots

Science.gov (United States)

Chen, Chao; Li, Xiaodong; Thiele, Frank

2018-06-01

For acoustic liners used in current commercial nacelles, in order to prevent any liquid accumulating in the resonators, drainage slots are incorporated on the partition walls between closely packed cavities. Recently, an experimental study conducted by Busse-Gerstengarbe et al. shown that the cell interaction introduced by drainage slots causes an additional dissipation peak which increases with the size of the slot. However, the variation of damping process due to drainage slots is still not fully understood. Therefore, a numerical study based on computational aeroacoustic methods is carried out to investigate the mechanism of the changed attenuation characteristics due to drainage slots in presence of grazing incident sound waves with low or high intensities. Different slot configurations are designed based on the generic non-locally reacting liner model adopted in the experimental investigation. Both 2-D and 3-D numerical simulations of only slit resonators are carried out. Numerical results indicate that the extra peak is a result of a resonance excited in the second cavity at specific frequency. Under high sound pressure level incoming waves, the basic characteristics of the acoustic performance remain. However, vortex shedding transpires at the resonances around both the slits and the drainage slot. Vorticity contours show that the connection of two coupled cavities decreases the strength of vortex shedding around the basic Helmholtz resonance due to a higher energy reflection. Meanwhile, the cell interaction significantly increases the vorticity magnitude near the extra resonant frequency. Finally, a semi-empirical model is derived to predict the extra attenuation peak frequency.

Rhythm experience and Africana culture trial (REACT!): A culturally salient intervention to promote neurocognitive health, mood, and well-being in older African Americans.

Science.gov (United States)

Lukach, Alexis J; Jedrziewski, M Kathryn; Grove, George A; Mechanic-Hamilton, Dawn J; Williams, Shardae S; Wollam, Mariegold E; Erickson, Kirk I

2016-05-01

The Rhythm Experience and Africana Culture Trial (REACT!) is a multi-site randomized controlled intervention study designed to examine the efficacy of using African Dance as a form of moderate-intensity physical activity to improve cognitive function in older African Americans. African Americans are almost two times more likely than Caucasians to experience cognitive impairment in late adulthood. This increased risk may be attributed to lower level and quality of education, lower socioeconomic status, and higher prevalence of vascular diseases, type 2 diabetes, hypertension, and obesity, all of which are recognized as risk factors for dementia. Fortunately, interventions targeting cardiovascular health (i.e., physical activity) are associated with improved neurocognitive function and a reduced risk for dementia, so African Americans may be particularly suited for interventions targeting cardiovascular health and cognitive function. Here, we describe a randomized intervention protocol for increasing physical activity in older (65-75years) African Americans. Participants (n=80) at two study locations will be randomized into one of two groups. The treatment group will participate in African Dance three times per week for six months and the control group will receive educational training on Africana history and culture, as well as information about health behaviors, three times per week for six months. If successful, the REACT! study may transform community interventions and serve as a platform and model for testing other populations, age groups, and health outcomes, potentially identifying novel and creative methods for reducing or eliminating health disparities. Copyright © 2016 Elsevier Inc. All rights reserved.

MPSalsa a finite element computer program for reacting flow problems. Part 2 - user`s guide

Energy Technology Data Exchange (ETDEWEB)

Salinger, A.; Devine, K.; Hennigan, G.; Moffat, H. [and others

1996-09-01

This manual describes the use of MPSalsa, an unstructured finite element (FE) code for solving chemically reacting flow problems on massively parallel computers. MPSalsa has been written to enable the rigorous modeling of the complex geometry and physics found in engineering systems that exhibit coupled fluid flow, heat transfer, mass transfer, and detailed reactions. In addition, considerable effort has been made to ensure that the code makes efficient use of the computational resources of massively parallel (MP), distributed memory architectures in a way that is nearly transparent to the user. The result is the ability to simultaneously model both three-dimensional geometries and flow as well as detailed reaction chemistry in a timely manner on MT computers, an ability we believe to be unique. MPSalsa has been designed to allow the experienced researcher considerable flexibility in modeling a system. Any combination of the momentum equations, energy balance, and an arbitrary number of species mass balances can be solved. The physical and transport properties can be specified as constants, as functions, or taken from the Chemkin library and associated database. Any of the standard set of boundary conditions and source terms can be adapted by writing user functions, for which templates and examples exist.

How do patients and providers react to different incentives in the Chinese multiple health security systems?

Science.gov (United States)

Zhang, Chun-Yu; Hashimoto, Hideki

2015-03-05

China has achieved universal health insurance coverage. This study examined how patients and hospitals react to the different designs of the plans and to monitoring of patients by the local authority in the Chinese multiple health security schemes. The sample for analysis consisted of 1006 orthopedic inpatients who were admitted between January and December 2011 at a tertiary teaching hospital located in Beijing. We conducted general linear regression analyses to investigate whether medical expenditure and length of stay differed according to the different incentives. Patients under plans with lower copayment rates consumed significantly more medication compared with those under plans with higher copayment rates. Under plans with an annual ceiling for insurance coverage, patients spent significantly more in the second half of the year than in the first half of the year. The length of stay was shorter among patients when there were government monitoring and a penalty to the hospital service provider. Our results indicate that the different designs and monitoring of the health security systems in China cause opportunistic behavior by patients and providers. Reformation is necessary to reduce those incentives, and improve equity and efficiency in healthcare use.

Synthesis of a Cementitious Material Nanocement Using Bottom-Up Nanotechnology Concept: An Alternative Approach to Avoid CO2 Emission during Production of Cement

Directory of Open Access Journals (Sweden)

Byung Wan Jo

2014-01-01

Full Text Available The world’s increasing need is to develop smart and sustainable construction material, which will generate minimal climate changing gas during their production. The bottom-up nanotechnology has established itself as a promising alternative technique for the production of the cementitious material. The present investigation deals with the chemical synthesis of cementitious material using nanosilica, sodium aluminate, sodium hydroxide, and calcium nitrate as reacting phases. The characteristic properties of the chemically synthesized nanocement were verified by the chemical composition analysis, setting time measurement, particle size distribution, fineness analysis, and SEM and XRD analyses. Finally, the performance of the nanocement was ensured by the fabrication and characterization of the nanocement based mortar. Comparing the results with the commercially available cement product, it is demonstrated that the chemically synthesized nanocement not only shows better physical and mechanical performance, but also brings several encouraging impacts to the society, including the reduction of CO2 emission and the development of sustainable construction material. A plausible reaction scheme has been proposed to explain the synthesis and the overall performances of the nanocement.

A Two-Temperature Open-Source CFD Model for Hypersonic Reacting Flows, Part Two: Multi-Dimensional Analysis †

Directory of Open Access Journals (Sweden)

Vincent Casseau

2016-12-01

Full Text Available hy2Foam is a newly-coded open-source two-temperature computational fluid dynamics (CFD solver that has previously been validated for zero-dimensional test cases. It aims at (1 giving open-source access to a state-of-the-art hypersonic CFD solver to students and researchers; and (2 providing a foundation for a future hybrid CFD-DSMC (direct simulation Monte Carlo code within the OpenFOAM framework. This paper focuses on the multi-dimensional verification of hy2Foam and firstly describes the different models implemented. In conjunction with employing the coupled vibration-dissociation-vibration (CVDV chemistry–vibration model, novel use is made of the quantum-kinetic (QK rates in a CFD solver. hy2Foam has been shown to produce results in good agreement with previously published data for a Mach 11 nitrogen flow over a blunted cone and with the dsmcFoam code for a Mach 20 cylinder flow for a binary reacting mixture. This latter case scenario provides a useful basis for other codes to compare against.

Luminescent properties of [UO{sub 2}(TFA){sub 2}(DMSO){sub 3}], a promising material for sensing and monitoring the uranyl ion

Energy Technology Data Exchange (ETDEWEB)

Martin-Ramos, Pablo; Silva, Manuela Ramos; Silva, Pedro S. Pereira da [Centro de Fisica da Universidade de Coimbra (CFisUC), Department of Physics, Universidade de Coimbra (Portugal); Costa, Ana L.; Melo, J. Sergio Seixas de [Centro de Quimica de Coimbra, Department of Chemistry, Universidade de Coimbra (Portugal); Pereira, Laura C.J. [Centro de Ciencias e Tecnologias Nucleares, Instituto Superior Tecnico, Universidade de Lisboa, Bobadela LRS (Portugal); Martin-Gil, Jesus, E-mail: pmr@unizar.es [Advanced Materials Laboratory, Escuela Tecnica Superior de Ingenierias Agrarias, University of Valladolid, Palencia (Spain)

2016-03-15

An uranyl complex [UO{sub 2}(TFA){sub 2}(DMSO){sub 3}] (TFA=deprotonated trifluoroacetic acid; DMSO=dimethyl sulfoxide) has been successfully synthesized by reacting UO{sub 2}(CH{sub 3}COO){sub 2} ·H{sub 2} O with one equivalent of (CF{sub 3} CO){sub 2} O and DMSO. The complex has been characterized by single-crystal X-ray diffraction, X-ray powder diffraction, elemental analysis, FTIR spectroscopy, thermal analysis and absorption and emission spectroscopies. The spectroscopic properties of the material make it suitable for its application in the sensing and monitoring of uranyl in the PUREX process. (author)

Atomic and Plasma-Material Interaction Data for Fusion. V. 16

International Nuclear Information System (INIS)

Braams, B.J.; Chung, H.-K.

2014-03-01

A wide variety of atomic, molecular, radiative and plasma-wall interaction processes involving a mixture of atoms, ions and molecules occur in the plasmas produced in nuclear fusion experiments. In the low temperature divertor and near wall region, molecules and molecular ions are formed. The plasma particles react with electrons and with each other. Plasma modelling requires cross-sections and rate coefficients for all these processes, and in addition spectral signatures to support interpretation of data from fusion experiments. The mission of the International Atomic Energy Agency Nuclear Data Section (IAEA/NDS) in the area of atomic and molecular data is to enhance the competencies of Member States in their research into nuclear fusion through the provision of internationally recommended atomic, molecular, plasma-material interaction and material properties databases. One mechanism by which the IAEA pursues this mission is the Coordinated Research Project (CRP). The present volume of Atomic and Plasma-Material Interaction Data for Fusion contains contributions from participants in the CRP 'Atomic and Molecular Data for Plasma Modelling' (2004-2008). This CRP was concerned with data for processes in the near wall and divertor plasma and plasma-wall interaction in fusion experiments, with focus on cross-sections for molecular reactions. Participants in the CRP came from 14 different institutes, many with strong ties to fusion plasma modelling and experiment. D. Humbert of the Nuclear Data Section was scientific secretary of the CRP. Participants' contributions for this volume were collected and refereed after the conclusion of the CRP

Electrocatalytic hydrogenation of organic molecules on conductive new catalytic material

Energy Technology Data Exchange (ETDEWEB)

Tountian, D. [Louis Pasteur Univ., Strasbourg (France). Laboratoire d' Electrochimie et de Chimie Physique du Corps Solide; Sherbrooke Univ., Sherbrooke, PQ (Canada). Dept. de Chimie, Centre de Recherche en Electrochimie et Electrocatalyse; Brisach-Wittmeyer, A.; Menard, H. [Sherbrooke Univ., Sherbrooke, PQ (Canada). Dept. de Chimie, Centre de Recherche en Electrochimie et Electrocatalyse; Nkeng, P.; Poillerat, G. [Louis Pasteur Univ., Strasbourg (France). Laboratoire d' Electrochimie et de Chimie Physique du Corps Solide

2008-07-01

Electrocatalytic hydrogenation (ECH) of organic molecules is a process where chemisorbed hydrogen is produced by electroreduction of water which reacts with the species in bulk. Greater emphasis is being placed on improving the nature of the building material of the electrodes in order to increase ECH efficiency. The effectiveness of the ECH is known to be linked to the nature of electrode materials used and their adsorption properties. This work presented the effect of conductive support material on ECH. The conductive catalysts were obtained from tin dioxide which is chemically stable. Palladium was the catalytic metal used in this study. The production of chemisorbed hydrogen was shown to depend on the quantity of metallic nanoaggregates in electrical contact with the reticulated vitreous carbon use as electrode. The conductive support, F-doped tin dioxide, was obtained by the sol-gel method. The electrocatalysts were characterized by different methods as resistivity measurements, linear sweep voltammetry, XRD, SEM, TGA/DSC, and FTIR analysis. The effects of temperature and time of calcination were also investigated. The study showed that the F-doped SnO2 electrocatalyst appeared to increase the rate of phenol electrohydrogenation. It was concluded that the improved electrocatalytic activity of Pd/F-doped SnO2 can be attributed to the simultaneous polarization of all the metallic Pd nanoaggregates present on the surface as well as in the pores of the matrix by contact with RVC. This results in a better production of chemisorbed atomic hydrogen with a large number of adlienation points. 9 refs., 3 figs.

[Patient's Autonomy and Information in Psycho-Oncology: Computer Based Distress Screening for an Interactive Treatment Planning (ePOS-react)].

Science.gov (United States)

Schäffeler, Norbert; Sedelmaier, Jana; Möhrer, Hannah; Ziser, Katrin; Ringwald, Johanna; Wickert, Martin; Brucker, Sara; Junne, Florian; Zipfel, Stephan; Teufel, Martin

2017-07-01

To identify distressed patients in oncology using screening questionnaires is quite challenging in clinical routine. Up to now there is no evidence based recommendation which instrument is most suitable and how to put a screening to practice. Using computer based screening tools offers the possibility to automatically analyse patient's data, inform psycho-oncological and medical staff about the results, and use reactive questionnaires. Studies on how to empower patients in decision making in psycho-oncology are rare.Methods Women with breast and gynaecological cancer have been consecutively included in this study (n=103) at time of inpatient surgical treatment in a gynaecological clinic. They answered the computer based screening questionnaire (ePOS-react) for routine distress screening at time of admission. At the end of the tool an individual recommendation concerning psycho-oncological treatment is given ( i) psycho-oncological counselling, ii) brief psycho-oncological contact, iii) no treatment suggestion). The informed patients could choose autonomously either the recommended treatment or an individually more favoured alternative possibility. Additionally, a clinical interview (approx. 30 min) based on the "Psychoonkologische Basisdiagnostik (PO-Bado)" has been carried out for a third-party assessment of patients' need for treatment.Results 68.9% followed the treatment recommendation. 22.3% asked for a more "intense" (e. g. counselling instead of recommended brief contact) and 8,7% for a "less intense" intervention than recommended. The accordance of third-party assessment (clinical interview "PO-Bado") and treatment recommendation is about 72.8%. The accordance of third-party assessment and patient's choice (ePOS-react) is about 58.3%. The latter is smaller because 29.1% asked for a brief psycho-oncological contact for whom from the third-party assessment's perspective no indication for treatment has been existent.Discussion A direct response of the

Chemical deposition methods using supercritical fluid solutions

Science.gov (United States)

Sievers, Robert E.; Hansen, Brian N.

1990-01-01

A method for depositing a film of a desired material on a substrate comprises dissolving at least one reagent in a supercritical fluid comprising at least one solvent. Either the reagent is capable of reacting with or is a precursor of a compound capable of reacting with the solvent to form the desired product, or at least one additional reagent is included in the supercritical solution and is capable of reacting with or is a precursor of a compound capable of reacting with the first reagent or with a compound derived from the first reagent to form the desired material. The supercritical solution is expanded to produce a vapor or aerosol and a chemical reaction is induced in the vapor or aerosol so that a film of the desired material resulting from the chemical reaction is deposited on the substrate surface. In an alternate embodiment, the supercritical solution containing at least one reagent is expanded to produce a vapor or aerosol which is then mixed with a gas containing at least one additional reagent. A chemical reaction is induced in the resulting mixture so that a film of the desired material is deposited.

Preparation of epoxy/zirconia hybrid materials via in situ polymerization using zirconium alkoxide coordinated with acid anhydride

International Nuclear Information System (INIS)

Ochi, Mitsukazu; Nii, Daisuke; Harada, Miyuki

2011-01-01

Highlights: → Novel epoxy/zirconia hybrid materials were synthesized via in situ polymerization using zirconium alkoxide coordinated with acid anhydride. → The half-ester compound of acid anhydride desorbed from zirconium played as curing agent of epoxy resin. → The zirconia was uniformly dispersed in the epoxy matrix on the nanometer or sub-nanometer scale by synchronizing the epoxy curing and sol-gel reactions. → The refractive indices of the hybrid materials significantly improved with an increase in the zirconia content. - Abstract: Novel epoxy/zirconia hybrid materials were synthesized using a bisphenol A epoxy resin (diglycidyl ether of bisphenol A; DGEBA), zirconium(IV)-n-propoxide (ZTNP), and hexahydrophthalic anhydride (HHPA) via in situ polymerization. HHPA played two roles in this system: it acted as a modifier to control the hydrolysis and condensation reactions of zirconium alkoxide and also as a curing agent - the half-ester compound of HHPA desorbed from zirconium reacted with the epoxy resin to form the epoxy network. As a result, both the sol-gel reaction and epoxy curing occurred simultaneously in a homogeneous solution, and organic-inorganic hybrid materials were readily obtained. Further, the zirconia produced by the in situ polymerization was uniformly dispersed in the epoxy matrix on the nanometer or sub-nanometer scale; thus, hybrid materials that exhibited excellent optical transparency were obtained. Furthermore, the heat resistance of the hybrid materials could be improved by hybridization with zirconia. And, the refractive indices of the hybrid materials significantly improved with an increase in the zirconia content.

COMPARISON OF SELECTED PHYSICAL PROPERTIES OF TESTED NANOSUSPENSIONS – THE RESULTS OF THE EXPERIMENTAL RESEARCH OF THE DEGREE OF SEDIMENTATION AND THE DEPTH OF PENETRATION IN REFERENCE MATERIALS IN LABORATORY CONDITIONS

Directory of Open Access Journals (Sweden)

Klára Kroftová

2017-10-01

Full Text Available Between used and already verified technologies for the reinforcement of plasters mainly include nanosuspension containing nanoparticles of calcium hydroxide and nanomaterials based on magnesium hydroxide and barium carbonate. Individual lime nanosuspension, which consists of nanoparticles of calcium hydroxide, are dispersed in an alcoholic environment and they differ from each concentration and type of alcohol. When the material is cured, carbonatation occurs, as well as in the case of fresh plaster, where the calcium hydroxide reacts with atmospheric carbon dioxide to produce calcium carbonate. Due to the deposition of calcium carbonate in the damaged material, occurs re-strengthened ties and its hardening. The undoubted advantage of the consolidation of plaster using nanolime is the low number of impregnation cycles, where after a few applications nanosuspension occurs to the reinforcement of degraded material.

Single-cell genomics reveals features of a Colwellia species that was dominant during the Deepwater Horizon oil spill

Directory of Open Access Journals (Sweden)

Olivia eMason

2014-07-01

Full Text Available During the Deepwater Horizon (DWH oil spill in the Gulf of Mexico a deep-sea hydrocarbon plume developed resulting in a rapid succession of bacteria. Colwellia eventually supplanted Oceanospirillales, which dominated the plume early in the spill. These successional changes may have resulted, in part, from the changing composition and abundance of hydrocarbons over time. Colwellia abundance peaked when gaseous and simple aromatic hydrocarbons increased, yet the metabolic pathway used by Colwellia in hydrocarbon disposition is unknown. Here we used single-cell genomics to gain insights into the genome properties of a Colwellia enriched during the DWH deep-sea plume. A single amplified genome (SAG of a Colwellia cell isolated from a DWH plume, closely related (avg. 98% 16S rRNA gene similarity to other plume Colwellia, was sequenced and annotated. The SAG was similar to the sequenced isolate Colwellia psychrerythraea 34H (84% avg. nucleotide identity. Both had genes for denitrification, chemotaxis and motility, adaptations to cold environments, and a suite of nutrient acquisition genes. The Colwellia SAG may be capable of gaseous and aromatic hydrocarbon degradation, which contrasts with a DWH plume Oceanospirillales SAG genome which encoded non-gaseous n-alkane and cycloalkane degradation. The disparate hydrocarbon degradation pathways are consistent with hydrocarbons that were abundant at different times in the deep-sea plume; first, non-gaseous n-alkanes and cycloalkanes that could be degraded by Oceanospirillales, followed by gaseous, and simple aromatic hydrocarbons that may have been degraded by Colwellia. These insights into the genomic properties of a Colwellia species, which were supported by existing metagenomic sequence data from the plume and DWH contaminated sediments, help further our understanding of the successional changes in the dominant microbial players in the plume over the course of the DWH spill.

Inert materials for the GFR fuel. Characterizations, chemical interactions and irradiation damage

International Nuclear Information System (INIS)

Audubert, Fabienne; Carlot, Gaoelle; Lechelle, Jacques; David, Laurent; Gomes, Severine

2005-01-01

In the framework of an extensive R and D Program on GFR fuel, studies on inert materials have been performed at the French Atomic Energy Commission (CEA). The inert materials would be associated with the fuel with the aim of featuring an efficient barrier to radiotoxic species with regard to the cooling circuit of the reactor. Potential matrices identified for dispersion fuels or particles fuels are SiC, TiN, ZrN, ZrC, TiC. Physical microstructural and thermal properties have been determined in order to evaluate elaboration process effects. The evolution under irradiation of thermal properties (such as conductivity, diffusivity) of the materials has been studied using heavy ions to simulate fission product irradiation. After irradiation, scanning thermal microscopy is used to investigate the thermal degradation of the materials. Thermal conductivity variations were obtained on TiC irradiated with krypton ion at an energy of 86 MeV and a fluence of 5.10 15 ions.cm -2 . They are quantified at 19 W.m -1 .K -1 . On other materials such as SiC, ZrC, TiN, no thermal conductivity contrast was shown. Reactivity between the inert matrix (SiC or TiN) and the fuel (U, Pu)N have been evaluated on powders and on ceramic samples in contact by a thermal treatment under several atmospheres. It was shown that SiC reacts with (U, Pu)N in various atmospheres making secondary phases as PuSi 2 , USi 2 , U 20 Si 16 C 3 . TiN behaviour seems to be better: the only reactivity which may take place would be a variation of the nitrogen stoichiometry in TiN and (U, Pu)N at the interface. (author)

Proceedings of the Japan-U.S. workshop P-119 on 14 MeV neutron source for material R and D based on plasma devices

International Nuclear Information System (INIS)

Miyahara, A.; Coensgen, F.H.

1988-06-01

In addition to the development of an adequate means to contain reacting D-T plasma in the range of 100 million deg K, the successful development of nuclear fusion as an energy source requires the development of new long-lived, low-activation materials. These new fusion reactor materials should not become radioactive when subjected to intense neutron irradiation for a long period. If the induced radioactivity cannot be entirely avoided, it must be short-lived and at relatively low level. The material development is already in progress using existing fission irradiation facilities and low level 14 MeV neutron sources. But the final selection and qualification of fusion reactor materials will require end of life testing. The neutron irradiation facilities for this purpose, the approximation of D-T neutron spectrum and the design of fusion material irradiation test (FMIT) are discussed. The workshop P-119 was organized to promote the development of plasma-based neutron sources. The presentation of each concept included its physics basis, neutron field characteristics, the required research and development and their schedules, and the rough estimation of the costs for development, construction and operation. (K.I.)

To Encounter, to Build the World and to Become a Human Being. Advocating for a Material-Cultural Turn in Developmental Psychology.

Science.gov (United States)

Moro, Christiane

2016-12-01

Why have material world of daily life and material objects in their conventional features or to say it in other words, why have the mundane world and mundane objects, in which the human beings live and children come to, encounter, experience and develop through, received so little attention from psychologists thus remaining a blind spot in mainstream developmental psychology? Certainly the object has not been totally forgotten (e.g. Piaget's constructivist paradigm) but it has been considered as theoretically determined by the categories of understanding (cf. Kant), and considered as a key to understanding the world in its physical properties by the infant. But the material world and the material objects that are used for everyday purposes (i.e. pragmatically) belonging to material culture, have been totally neglected by developmental psychologists. Reacting to the Kantian agenda of developmental psychology but also to heterodox non developmentalist thinkers such as Gibson who is a growing source of inspiration for developmental psychologists today, we challenge the taken-for-granted mundane world, arguing for the importance of material objects related to material culture in psychological development during the prelinguistic period. On the basis of recent research in early development grounded in the Vygotskian paradigm, we discuss this issue through Marxist Anthropology, Material Culture Studies and Phenomenology. As a consequence we advocate for a material-cultural turn in psychological development in order to place the issue of material world and material objects in their pragmatic and semiotic features on the agenda of developmental psychology.

Role of tropomyosin as a cross-reacting allergen in sensitization to cockroach in patients from Martinique (French Caribbean island) with a respiratory allergy to mite and a food allergy to crab and shrimp

NARCIS (Netherlands)

Purohit, A.; Shao, J.; Degreef, J. M.; van Leeuwen, A.; van Ree, R.; Pauli, G.; de Blay, F.

2007-01-01

BACKGROUND: Tropomyosin has been described as cross-reacting allergen between mite, cockroach and shrimp. METHODS: In 13 patients with asthma and/or rhinitis sensitized to mite and/or German cockroach and presenting urticaria, oral allergy syndrome or angio-edema upon eating shrimp and/or crab, we

Enhanced electrochemical properties of LiNiO{sub 2}-based cathode materials by nanoscale manganese carbonate treatment

Energy Technology Data Exchange (ETDEWEB)

Zhao, Junkai; Wang, Zhixing, E-mail: zxwang.csu@hotmail.com; Guo, Huajun; Li, Xinhai

2017-05-01

Highlights: • Li residuals are consumed during the process of modification. • MnO{sub 2} coating layer can protect bulk material from the erosion of electrolyte. • The electrochemical performance is enhanced by the nanosacle MnCO{sub 3} treatment. • The enhancement of coating can be strengthened by the removal of lithium impurities. - Abstract: LiNiO{sub 2}-based layered oxides are of great importance as cathode materials for rechargeable batteries. In this paper, illustrating LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} as an example, the effect of nanoscale MnCO{sub 3} treatment on LiNiO{sub 2}-based materials is investigated for the first time. The structures of materials and the properties about the object surface are characterized by XRD, SEM, TEM, EDAX and XPS. The results demonstrate that a part of MnCO{sub 3} is able to react with lithium impurities to form nonstoichiometric Li{sub x}Mn{sub y}O{sub 4} and the rest of MnCO{sub 3} is converted to MnO{sub 2} coating on the surface of the material in situ. After 100 repeated cycles at 1C, the modified material exhibits a capacity retention rate of 91.2%, while the bare material only remains 84.8%. And the modified material exhibits more significantly improved cycling stability when cycling at 60 °C, maintaining 85.7% of its initial capacity at 1C after 100th cycles. The consumption of Li impurities can decelerate the decomposition of electrolyte during cycling, thus result in less resistive byproducts. Moreover, the obtained MnO{sub 2} coating layer acts as an isolating layer to suppress the drastic reaction between active material and electrolyte. This synergistic effect is responsible for the excellent properties of MnCO{sub 3}-modified material.

32Si as natural tracer : measurement, global distribution and application

International Nuclear Information System (INIS)

Morgenstern, U.

1997-01-01

Cosmogenic 32 Si (half-life 140 years) can be applied to the study of environmental circulation processes in the time range of the last 1000 years, a key period for modelling past climate change. Its non-gaseous nature and fairly constant production rate are favourable to quantifying its roe in environmental processes. Applications of 32 Si method were limited due to uncertainties in half-life and poor knowledge of its global distribution, and to its very small natural concentration. Recent developments concerning these problems will be presented with special emphasis to measurement and global distribution, and to application in study of groundwater recharge and flow, glacier dynamics, soil erosion rates and sedimentation in lakes and oceans. (author)

KEKCB electron cyclotron resonance charge breeder at TRIAC

International Nuclear Information System (INIS)

Imai, N.; Jeong, S. C.; Oyaizu, M.; Arai, S.; Fuchi, Y.; Hirayama, Y.; Ishiyama, H.; Miyatake, H.; Tanaka, M. H.; Okada, M.; Watanabe, Y. X.; Ichikawa, S.; Kabumoto, H.; Osa, A.; Otokawa, Y.; Sato, T. K.

2008-01-01

The KEKCB is an electron cyclotron resonance (ECR) ion source for converting singly charged ions to multicharged ones at Tokai Radioactive Ion Accelerator Complex. By using the KEKCB, singly charged gaseous and nongaseous ions were converted to multicharged ones of A/q≅7 with efficiencies of 7% and 2%, respectively. The conversion efficiency was found to be independent of the lifetime of the radioactive nuclei having lifetimes of the order of one second. Three collimators located at the entrance and the exit of the KEKCB defined the beam axis and facilitated beam injection. Grinding and washing the surfaces of aluminum electrode and plasma chamber dramatically reduced impurities originating from the ECR plasma of the KEKCB

The property distance index PD predicts peptides that cross-react with IgE antibodies

Science.gov (United States)

Ivanciuc, Ovidiu; Midoro-Horiuti, Terumi; Schein, Catherine H.; Xie, Liping; Hillman, Gilbert R.; Goldblum, Randall M.; Braun, Werner

2009-01-01

Similarities in the sequence and structure of allergens can explain clinically observed cross-reactivities. Distinguishing sequences that bind IgE in patient sera can be used to identify potentially allergenic protein sequences and aid in the design of hypo-allergenic proteins. The property distance index PD, incorporated in our Structural Database of Allergenic Proteins (SDAP, http://fermi.utmb.edu/SDAP/), may identify potentially cross-reactive segments of proteins, based on their similarity to known IgE epitopes. We sought to obtain experimental validation of the PD index as a quantitative predictor of IgE cross-reactivity, by designing peptide variants with predetermined PD scores relative to three linear IgE epitopes of Jun a 1, the dominant allergen from mountain cedar pollen. For each of the three epitopes, 60 peptides were designed with increasing PD values (decreasing physicochemical similarity) to the starting sequence. The peptides synthesized on a derivatized cellulose membrane were probed with sera from patients who were allergic to Jun a 1, and the experimental data were interpreted with a PD classification method. Peptides with low PD values relative to a given epitope were more likely to bind IgE from the sera than were those with PD values larger than 6. Control sequences, with PD values between 18 and 20 to all the three epitopes, did not bind patient IgE, thus validating our procedure for identifying negative control peptides. The PD index is a statistically validated method to detect discrete regions of proteins that have a high probability of cross-reacting with IgE from allergic patients. PMID:18950868

A commercial ELISA detects high levels of human H5 antibody but cross-reacts with influenza A antibodies.

Science.gov (United States)

Stelzer-Braid, Sacha; Wong, Bruce; Robertson, Peter; Lynch, Garry W; Laurie, Karen; Shaw, Robert; Barr, Ian; Selleck, Paul W; Baleriola, Cristina; Escott, Ros; Katsoulotos, Gregory; Rawlinson, William D

2008-10-01

Commercial serological assays to determine influenza A H5N1 infection are available, although the accuracy and reproducibility of these are not reported in detail. This study aimed to assess the validity of a commercial ELISA H5 hemagglutinin (HA) antibody kit. A commercial ELISA for detection of antibodies towards influenza A H5 HA was evaluated using human sera from vaccinated individuals. The ELISA was used to screen 304 sera with elevated influenza A complement fixation titres collected between the period 1995-2007. The ELISA was found to be accurate for sera with high levels of anti-H5 antibodies, and would be useful in clinical settings where a rapid result is required. Thirteen of the stored sera were positive using the ELISA, but were confirmed as negative for H5N1 exposure using further serological tests. Absorption studies suggested that antibodies towards seasonal H3N2 and H1N1 influenza may cross-react with H5 antigen, giving false positive results with the ELISA.

An LES-PBE-PDF approach for modeling particle formation in turbulent reacting flows

Science.gov (United States)

Sewerin, Fabian; Rigopoulos, Stelios

2017-10-01

Many chemical and environmental processes involve the formation of a polydispersed particulate phase in a turbulent carrier flow. Frequently, the immersed particles are characterized by an intrinsic property such as the particle size, and the distribution of this property across a sample population is taken as an indicator for the quality of the particulate product or its environmental impact. In the present article, we propose a comprehensive model and an efficient numerical solution scheme for predicting the evolution of the property distribution associated with a polydispersed particulate phase forming in a turbulent reacting flow. Here, the particulate phase is described in terms of the particle number density whose evolution in both physical and particle property space is governed by the population balance equation (PBE). Based on the concept of large eddy simulation (LES), we augment the existing LES-transported probability density function (PDF) approach for fluid phase scalars by the particle number density and obtain a modeled evolution equation for the filtered PDF associated with the instantaneous fluid composition and particle property distribution. This LES-PBE-PDF approach allows us to predict the LES-filtered fluid composition and particle property distribution at each spatial location and point in time without any restriction on the chemical or particle formation kinetics. In view of a numerical solution, we apply the method of Eulerian stochastic fields, invoking an explicit adaptive grid technique in order to discretize the stochastic field equation for the number density in particle property space. In this way, sharp moving features of the particle property distribution can be accurately resolved at a significantly reduced computational cost. As a test case, we consider the condensation of an aerosol in a developed turbulent mixing layer. Our investigation not only demonstrates the predictive capabilities of the LES-PBE-PDF model but also

[Determination of bisphenol A from toys and food contact materials by derivatization and gas chromatography-mass spectrometry].

Science.gov (United States)

Gao, Yonggang; Zhang, Yanyan; Gao, Jianguo; Zhang, Huiling; Zheng, Lisha; Chen, Jing

2012-10-01

A method was developed for the determination of bisphenol A (BPA) in toys and food contact materials. The BPA was extracted with Soxhlet extraction method from the sample and reacted with acetic anhydride. The final product was determined by gas chromatography-mass spectrometry (GC-MS). To achieve the optimum derivatization performance, the derivatization time and dosage of derivatization reagent etc. were investigated. Under the optimized experimental conditions, the final product was stable and the peak shape was good. The linearity of the derivative was good in the range of 0.05 to 50 mg/L with the correlation coefficient (r2) above 0.999. The recoveries ranged from 80% to 93% at the spiked levels of 0.05, 1.00, 10.00 mg/kg with the relative standard deviations (RSDs) less than 3.7%. The limit of detection (S/N = 3) was 10 microg/kg. The method is accurate and has high recovery. The method is suitable for the inspection of bisphenol A in toys and food contact materials.

Surface passivation process of compound semiconductor material using UV photosulfidation

Science.gov (United States)

Ashby, Carol I. H.

1995-01-01

A method for passivating compound semiconductor surfaces by photolytically disrupting molecular sulfur vapor with ultraviolet radiation to form reactive sulfur which then reacts with and passivates the surface of compound semiconductors.

Effect of starting materials and processing variables for the production of discontinuous filament Nb3Sn wire

International Nuclear Information System (INIS)

Upadhyay, P.L.; Dew-Hughes, D.

1986-01-01

Discontinuous multifilamentary wires of Nb 3 Sn have been prepared from compacted mixtures of 30 wt. %Nb in Cu, extruded, drawn, annealed, tin plated and reacted. Processing variables include starting materials, extrusion ratio and extrusion temperature. Continuous lengths of wire could be satisfactorily produced from compacts of either ultra-pure Nb (VPN about 95 kg mm -2 ) and Cu powder or from centrifugal arc-cast Nb spheroids (VPN about 120 kg mm -2 ) and tough pitch Cu powder. After a total area reduction of 10 4 : 1, the latter materials resulted in long, unbroken, highly regular filaments of Nb about 6μm in diameter. The high degree of perfection of these filaments is due in part to the uniformity of the initial spheroids, compared to the highly irregular hydride-dehydride Nb powder. However their greater hardness requires that the spheroids be coprocessed in a less-pure Cu matrix. Critical currents were measured on helical specimens involving more than 1m length of wire, in fields up to 15T at 4.2 K, after reaction for various times at different temperatures. Overall current densities of 3 X 10 8 Am -2 were obtained at 12T in the best samples. Further reductions are expected to produce material with improved current densities

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

Saturated polyester resin, derived from the glycolysis of polyethyleneterephthalate (PET) was examined as an effective way for PET recycling. The glycolyzed PET (GPET) was reacted with the mixture of phthalic anhydride and ethylene glycol (EG) with varied compositions and their reaction kinetic were studied. During ...

Fracture Toughness Evaluation of Space Shuttle External Tank Thermal Protection System Polyurethane Foam Insulation Materials

Science.gov (United States)

McGill, Preston; Wells, Doug; Morgan, Kristin

2006-01-01

Experimental evaluation of the basic fracture properties of Thermal Protection System (TPS) polyurethane foam insulation materials was conducted to validate the methodology used in estimating critical defect sizes in TPS applications on the Space Shuttle External Fuel Tank. The polyurethane foam found on the External Tank (ET) is manufactured by mixing liquid constituents and allowing them to react and expand upwards - a process which creates component cells that are generally elongated in the foam rise direction and gives rise to mechanical anisotropy. Similarly, the application of successive foam layers to the ET produces cohesive foam interfaces (knitlines) which may lead to local variations in mechanical properties. This study reports the fracture toughness of BX-265, NCFI 24-124, and PDL-1034 closed-cell polyurethane foam as a function of ambient and cryogenic temperatures and knitline/cellular orientation at ambient pressure.

How does the public react when scientists disagree?

DEFF Research Database (Denmark)

Hunka, Agnieszka; Palmqvist, Annemette; Forbes, Valery E.

thematic analysis with a survey. We have collected materials from web pages on English-speaking internet sites and launched a web-based survey to study the general public’s response to the GMO controversy. Our preliminary results indicate that the lack of scientific consensus is the main and very serious...... in the judgement of experts seem to lie at the core of risk perception and successful risk communication with the general public. Yet, studies on the role of scientific consensus in perceiving risk are scarce. On the 19th of September, a study on long term toxicity of herbicide-tolerant, genetically modified maize...... study we focus on public reactions to scientific controversy surrounding the study of Seralini’s team, using this example as a case study. Our aim is to link perceived risk from GM organisms with the role of scientific consensus in risk communication. We employed a mixed-method approach, combining...

Single-Photon Ionization Soft-X-Ray Laser Mass Spectrometry of Potential Hydrogen Storage Materials

Science.gov (United States)

Dong, F.; Bernstein, E. R.; Rocca, J. J.

A desk-top size capillary discharge 46.9 nm lasear is applied in the gas phase study of nanoclusters. The high photon energy allows for single-photon ionization mass spectrometry with reduced cluster fragmentation. In the present studies, neutral Al m C n and Al m C n H x cluster are investigation for the first time. Single photon ionization through 46.9 nm, 118 nm, 193 nm lasers is used to detect neutral cluster distributions through time of flight mass spectrometry. Al m C n clusters are generated through laser ablation of a mixture of Al and C powders pressed into a disk. An oscillation of the vertical ionization energies (VIEs) of Al m C n clusters is observed in the experiments. The VIEs of Al m C n clusters changes as a function of the numbers of Al and C atoms in the clusters. Al m C n H x clusters are generated through an Al ablation plasma-hydrocarbon reaction, an Al-C ablation plasma reacting with H2 gas, or through cold Al m C n clusters reacting with H2 gas in a fast flow reactor. DFT and ab inito calculations are carried out to explore the structures, IEs, and electronic structures of Al m C n H x clusters. C=C bonds are favored for the lowest energy structures for Al m C n clusters. Be m C n H x are generated through a beryllium ablation plasma-hydrocarbon reaction and detected by single photon ionization of 193 nm laser. Both Al m C n H x and Be m C n H x are considered as potential hydrogen storage materials.

Aerodynamic characteristics and thermal structure of nonpremixed reacting swirling wakes at low Reynolds numbers

Energy Technology Data Exchange (ETDEWEB)

Huang, Rong F. [Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei (China); Yen, Shun C. [Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung (China)

2008-12-15

The aerodynamic characteristics and thermal structure of uncontrolled and controlled swirling double-concentric jet flames at low Reynolds numbers are experimentally studied. The swirl and Reynolds numbers are lower than 0.6 and 2000, respectively. The flow characteristics are diagnosed by the laser-light-sheet-assisted Mie scattering flow visualization method and particle image velocimetry (PIV). The thermal structure is measured by a fine-wire thermocouple. The flame shapes, combined images of flame and flow, velocity vector maps, streamline patterns, velocity and turbulence distributions, flame lengths, and temperature distributions are discussed. The flow patterns of the no-control case exhibit an open-top, single-ring vortex sitting on the blockage disc with a jetlike swirling flow evolving from the central disc face toward the downstream area. The rotation direction and size of the near-disc vortex, as well as the flow properties, change in different ranges of annulus swirl number and therefore induce three characteristic flame modes: weak swirling flame, lifted flame, and turbulent reattached flame. Because the near-disc vortex is open-top, the radial dispersion of the fuel-jet fluids is not significantly enhanced by the annulus swirling flow. The flows of the reacting swirling double-concentric jets at such low swirl and Reynolds numbers therefore present characteristics of diffusion jet flames. In the controlled case, the axial momentum of the central fuel jet is deflected radially by a control disc placed above the blockage disc. This arrangement can induce a large near-disc recirculation bubble and high turbulence intensities. The enhanced mixing hence tremendously shortens the flame length and enlarges the flame width. (author)

EMERGING TECHNOLOGY SUMMARY - SIMULTANEOUS DESTRUCTION OF ORGANICS AND STABILIZATION OF METALS IN SOILS

Science.gov (United States)

The Sulchem Process reacts the material being treated with elemental sulfur at elevated temperatures in an inert reactor system. Organic hydrocarbons react with the sulfur to form an inert fine solid of carbon and sulfur, hydrogen sulfide gas, and modest amounts of carbon disulfi...

SIMULTANEOUS DESTRUCTION OF ORGANICS AND STABILIZATION OF METALS IN SOILS

Science.gov (United States)

The Sulchem Process reacts the material being treated with elemental sulfur at elevated temperatures in an inert reactor system. Organic hydrocarbons react with the sulfur to form an inert fine solid of carbon and sulfur, hydrogen sulfide gas, and modest amounts of carbon disulfi...

A Two-Temperature Open-Source CFD Model for Hypersonic Reacting Flows, Part One: Zero-Dimensional Analysis

Directory of Open Access Journals (Sweden)

Vincent Casseau

2016-10-01

Full Text Available A two-temperature CFD (computational fluid dynamics solver is a prerequisite to any spacecraft re-entry numerical study that aims at producing results with a satisfactory level of accuracy within realistic timescales. In this respect, a new two-temperature CFD solver, hy2Foam, has been developed within the framework of the open-source CFD platform OpenFOAM for the prediction of hypersonic reacting flows. This solver makes the distinct juncture between the trans-rotational and multiple vibrational-electronic temperatures. hy2Foam has the capability to model vibrational-translational and vibrational-vibrational energy exchanges in an eleven-species air mixture. It makes use of either the Park TTv model or the coupled vibration-dissociation-vibration (CVDV model to handle chemistry-vibration coupling and it can simulate flows with or without electronic energy. Verification of the code for various zero-dimensional adiabatic heat baths of progressive complexity has been carried out. hy2Foam has been shown to produce results in good agreement with those given by the CFD code LeMANS (The Michigan Aerothermodynamic Navier-Stokes solver and previously published data. A comparison is also performed with the open-source DSMC (direct simulation Monte Carlo code dsmcFoam. It has been demonstrated that the use of the CVDV model and rates derived from Quantum-Kinetic theory promote a satisfactory consistency between the CFD and DSMC chemistry modules.

Dessicant materials screening for backfill in a salt repository

International Nuclear Information System (INIS)

Simpson, D.R.

1980-10-01

Maintaining an anhydrous environment around nuclear waste stored in a salt repository is a concern which can be alleviated by using a desiccant material for backfilling. Such a desiccant should desiccate a brine yet be non deliquescent, the hydrated product should have moderate thermal stability, and the desiccant should have a high capacity and be readily available. From a literature search MgO and CaO were identified for detailed study. These oxides, and an intimate mixture of the two obtained by calcining dolomite, were used in experiments to further determine their suitability. They proved to be excellent desiccants with a high water capacity. The hydrates of both have moderate thermal stability and a high water content. Both MgO and CaO react in an alkaline chloride brine forming oxychloride compounds with different waters of crystallization. Some of these compounds are the Sorel Cements. CaO hydrates to Ca(OH) 2 which carbonates with CO 2 in air to form CaCO 3 and release the hydrated water. Thus the intimate mixture of CaO and MgO from calcined dolomite may serve as a desiccant and remove CO 2 from the repository atmosphere

Dessicant materials screening for backfill in a salt repository

Energy Technology Data Exchange (ETDEWEB)

Simpson, D.R.

1980-10-01

Maintaining an anhydrous environment around nuclear waste stored in a salt repository is a concern which can be alleviated by using a desiccant material for backfilling. Such a desiccant should desiccate a brine yet be non deliquescent, the hydrated product should have moderate thermal stability, and the desiccant should have a high capacity and be readily available. From a literature search MgO and CaO were identified for detailed study. These oxides, and an intimate mixture of the two obtained by calcining dolomite, were used in experiments to further determine their suitability. They proved to be excellent desiccants with a high water capacity. The hydrates of both have moderate thermal stability and a high water content. Both MgO and CaO react in an alkaline chloride brine forming oxychloride compounds with different waters of crystallization. Some of these compounds are the Sorel Cements. CaO hydrates to Ca(OH)/sub 2/ which carbonates with CO/sub 2/ in air to form CaCO/sub 3/ and release the hydrated water. Thus the intimate mixture of CaO and MgO from calcined dolomite may serve as a desiccant and remove CO/sub 2/ from the repository atmosphere.

Thermal Activated Envelope

DEFF Research Database (Denmark)

Foged, Isak Worre; Pasold, Anke

2015-01-01

The research studies the making of a responsive architectural envelope based on bi-materials. The bi-materials are organized according to a method that combines different isotropic metals and plastic into an active composite structure that reacts to temperature variations. Through an evolutionary......, environmental dynamics and occupancy dynamics. Lastly, a physical prototype is created, which illustrates the physical expression of the bi-materials and the problems related to manufacturing of these composite structures.......The research studies the making of a responsive architectural envelope based on bi-materials. The bi-materials are organized according to a method that combines different isotropic metals and plastic into an active composite structure that reacts to temperature variations. Through an evolutionary...

Investigation of Microstructure and Microhardness in Self-Reacting Friction Stir Welded AA2014-T6 and AA2219-T87

Science.gov (United States)

Horton, K. Renee; McGill, Preston; Barkey, Mark

2011-01-01

Friction stir welding (FSW) is a solid state welding process with potential advantages for aerospace and automotive industries dealing with light alloys. Self-reacting friction stir welding (SR-FSW) is one variation of the FSW process being developed at the National Aeronautics and Space Administration (NASA) for use in the fabrication of propellant tanks. This work reports on the microstructure and microhardness of SR-FSW between two dissimilar aluminum alloys. Specifically, the study examines the cross section of the weld joint formed between an AA2014-T6 plate on the advancing side and an AA2219-T87 plate on the retreating side. The microstructural analysis shows an irregularly displaced weld seam from the advancing side past the thermo-mechanical affected zone (TMAZ) into the weld nugget region. There are sharp variations in the microhardness across the weld. These variations are described in the paper and mechanisms for their formation are discussed.

Simulations of Spray Reacting Flows in a Single Element LDI Injector With and Without Invoking an Eulerian Scalar PDF Method

Science.gov (United States)

Shih, Tsan-Hsing; Liu, Nan-Suey

2012-01-01

This paper presents the numerical simulations of the Jet-A spray reacting flow in a single element lean direct injection (LDI) injector by using the National Combustion Code (NCC) with and without invoking the Eulerian scalar probability density function (PDF) method. The flow field is calculated by using the Reynolds averaged Navier-Stokes equations (RANS and URANS) with nonlinear turbulence models, and when the scalar PDF method is invoked, the energy and compositions or species mass fractions are calculated by solving the equation of an ensemble averaged density-weighted fine-grained probability density function that is referred to here as the averaged probability density function (APDF). A nonlinear model for closing the convection term of the scalar APDF equation is used in the presented simulations and will be briefly described. Detailed comparisons between the results and available experimental data are carried out. Some positive findings of invoking the Eulerian scalar PDF method in both improving the simulation quality and reducing the computing cost are observed.

Brazilian natural fiber (jute as raw material for activated carbon production

Directory of Open Access Journals (Sweden)

CARLA F.S. ROMBALDO

2014-12-01

Full Text Available Jute fiber is the second most common natural cellulose fiber worldwide, especially in recent years, due to its excellent physical, chemical and structural properties. The objective of this paper was to investigate: the thermal degradation of in natura jute fiber, and the production and characterization of the generated activated carbon. The production consisted of carbonization of the jute fiber and activation with steam. During the activation step the amorphous carbon produced in the initial carbonization step reacted with oxidizing gas, forming new pores and opening closed pores, which enhanced the adsorptive capacity of the activated carbon. N2 gas adsorption at 77K was used in order to evaluate the effect of the carbonization and activation steps. The results of the adsorption indicate the possibility of producing a porous material with a combination of microporous and mesoporous structure, depending on the parameters used in the processes, with resulting specific surface area around 470 m2.g–1. The thermal analysis indicates that above 600°C there is no significant mass loss.

Oxidized limonene and oxidized linalool - concomitant contact allergy to common fragrance terpenes.

Science.gov (United States)

Bråred Christensson, Johanna; Karlberg, Ann-Therese; Andersen, Klaus E; Bruze, Magnus; Johansen, Jeanne D; Garcia-Bravo, Begoña; Giménez Arnau, Ana; Goh, Chee-Leok; Nixon, Rosemary; White, Ian R

2016-05-01

Limonene and linalool are common fragrance terpenes. Both oxidized R-limonene and oxidized linalool have recently been patch tested in an international setting, showing contact allergy in 5.2% and 6.9% of dermatitis patients, respectively. To investigate concomitant reactions between oxidized R-limonene and oxidized linalool in consecutive dermatitis patients. Oxidized R-limonene 3.0% (containing limonene hydroperoxides 0.33%) and oxidized linalool 6% (linalool hydroperoxides 1%) in petrolatum were tested in 2900 consecutive dermatitis patients in Australia, Denmark, Singapore, Spain, Sweden, and the United Kingdom. A total of 281 patients reacted to either oxidized R-limonene or oxidized linalool. Of these, 25% had concomitant reactions to both compounds, whereas 29% reacted only to oxidized R-limonene and 46% only to oxidized linalool. Of the 152 patients reacting to oxidized R-limonene, 46% reacted to oxidized linalool, whereas 35% of the 200 patients reacting to oxidized linalool also reacted to oxidized R-limonene. The majority of the patients (75%) reacted to only one of the oxidation mixtures, thus supporting the specificity of the reactions. The concomitant reactions to the two fragrance allergens suggest multiple sensitizations, which most likely reflect the exposure to the different fragrance materials in various types of consumer products. This is in accordance with what is generally seen for patch test reactions to fragrance materials. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Construct 3D porous hollow Co3O4 micro-sphere: A potential oxidizer of nano-energetic materials with superior reactivity

Science.gov (United States)

Wang, Jun; Zheng, Bo; Qiao, Zhiqiang; Chen, Jin; Zhang, Liyuan; Zhang, Long; Li, Zhaoqian; Zhang, Xingquan; Yang, Guangcheng

2018-06-01

High energy density and rapid reactivity are the future trend for nano-energetic materials. Energetic performance of nano-energetic materials depends on the interfacial diffusion and mass transfer during the reacted process. However, the development of desired structure to significantly enhance reactivity still remains challenging. Here we focused on the design and preparation of 3D porous hollow Co3O4 micro-spheres, in which gas-blowing agents (air) and maximize interfacial interactions were introduced to enhance mass transport and reduce the diffusion distance between the oxidizer and fuel (Aluminum). The 3D hierarchical Co3O4/Al based nano-energetic materials show a low-onset decomposition temperature (423 °C), and high heat output (3118 J g-1) resulting from porous and hollow nano-structure of Co3O4 micro-spheres. Furthermore, 3D hierarchical Co3O4/Al arrays were directly fabricated on the silicon substrate, which was fully compatible with silicon-based microelectromechanical systems to achieve functional nanoenergetics-on-a-chip. This approach provides a simple and efficient way to fabricate 3D ordered nano-energetic arrays with superior reactivity and the potential on the application in micro-energetic devices.

Monoclonal antibodies reactive with common tumor antigens on UV-induced tumors also react with hyperplastic UV-irradiated skin

International Nuclear Information System (INIS)

Spellman, C.W.; Beauchamp, D.A.

1986-01-01

Most murine skin tumors induced by ultraviolet light (UVB, 280-340 nm) can be successfully transplanted only into syngeneic hosts that have received subcarcinogenic doses of UVB. The tumor susceptible state is long-lived and mediated by T suppressor cells that control effector responses against common antigens on UV-induced tumors. Because antigen specific suppression arises prior to the appearance of a tumor, questions arise about the source of the original antigen. They have previously reported transplantation studies indicating that UV-irradiated skin is antigenically cross-reactive with UV-induced tumors. They now report on flow cytometry analyses showing that a series of MoAb reactive with common antigens expressed by UV-induced tumors are also reactive on cells from UV-irradiated skin. Various antigens appear at different times in the UV irradiation scheme, and some persist while others are transient. They speculate that the common antigens detected may be the ones to which functional suppression is directed. If true, these results suggest that successful tumors need not escape host defenses to emerge. Rather, tumors may arise and grow progressively if they express antigens that cross-react with specificities to which the host has previously mounted a suppressive response

Pre-existing IgG antibodies cross-reacting with the Fab region of infliximab predict efficacy and safety of infliximab therapy in inflammatory bowel disease

DEFF Research Database (Denmark)

Steenholdt, Casper; Palarasah, Yaseelan; Bendtzen, Klaus

2013-01-01

are common and may cross-react with the murine part of IFX. AIM: To investigate if Abs binding to IFX's Fab region (IFX-Fab) are present in IBD patients before exposure to IFX, and whether they predict efficacy and safety of IFX therapy. METHODS: Observational, retrospective cohort study of patients with CD...... (n = 29) and UC (n = 22). RESULTS: Pre-treatment levels of IFX-Fab reactive IgG Abs were significantly lower in CD patients in remission after 1 year of maintenance IFX (median 91 mU/L, n = 8) than in the rest of the patients (639 mU/L, n = 21; P ...

O-GlcNAc-specific antibody CTD110.6 cross-reacts with N-GlcNAc2-modified proteins induced under glucose deprivation.

Directory of Open Access Journals (Sweden)

Takahiro Isono

Full Text Available Modification of serine and threonine residues in proteins by O-linked β-N-acetylglucosamine (O-GlcNAc glycosylation is a feature of many cellular responses to the nutritional state and to stress. O-GlcNAc modification is reversibly regulated by O-linked β-N-acetylglucosamine transferase (OGT and β-D-N-acetylglucosaminase (O-GlcNAcase. O-GlcNAc modification of proteins is dependent on the concentration of uridine 5'-diphospho-N-acetylglucosamine (UDP-GlcNAc, which is a substrate of OGT and is synthesized via the hexosamine biosynthetic pathway. Immunoblot analysis using the O-GlcNAc-specific antibody CTD110.6 has indicated that glucose deprivation increases protein O-GlcNAcylation in some cancer cells. The mechanism of this paradoxical phenomenon has remained unclear. Here we show that the increased glycosylation induced by glucose deprivation and detected by CTD110.6 antibodies is actually modification by N-GlcNAc(2, rather than by O-GlcNAc. We found that this induced glycosylation was not regulated by OGT and O-GlcNAcase, unlike typical O-GlcNAcylation, and it was inhibited by treatment with tunicamycin, an N-glycosylation inhibitor. Proteomics analysis showed that proteins modified by this induced glycosylation were N-GlcNAc(2-modified glycoproteins. Furthermore, CTD110.6 antibodies reacted with N-GlcNAc(2-modified glycoproteins produced by a yeast strain with a ts-mutant of ALG1 that could not add a mannose residue to dolichol-PP-GlcNAc(2. Our results demonstrated that N-GlcNAc(2-modified glycoproteins were induced under glucose deprivation and that they cross-reacted with the O-GlcNAc-specific antibody CTD110.6. We therefore propose that the glycosylation status of proteins previously classified as O-GlcNAc-modified proteins according to their reactivity with CTD110.6 antibodies must be re-examined. We also suggest that the repression of mature N-linked glycoproteins due to increased levels of N-GlcNAc(2-modified proteins is a newly

Assessment of the Durability of Cementitious Materials in Repository Environment

International Nuclear Information System (INIS)

Vicente, R.; Marumo, J.T.; Miyamoto, H.; Isiki, V.L.K.; Ferreira, E.G.

2013-01-01

The Radioactive Waste Management Laboratory of the Energy and Nuclear Research Institute is developing the concept of a borehole repository for disused sealed radioactive sources drilled in a deep granite batholite. In this concept, the annular space between the well steel casing and the geological formation is backfilled with cement paste. The hardened cement paste functions as an additional barrier against the escape of radionuclides from the repository and their migration to the environment. It also functions as an obstacle to the flow of groundwater between different layers of the geological setting crossed by the borehole. The long term behavior of hydrated cement compounds is yet incompletely known and therefore more research is needed to increase the confidence on the performance of the material under the repository conditions as required. For the repository to achieve the required performance, the cement paste must be durable. However, in a deep repository, the cementitious materials is exposed to the deleterious action of high temperatures and pressures, the radiation field created by the radioactive sources and aggressive ion species that may be present in groundwater. Furthermore, it is necessary to consider that the cement paste is unstable in the long term because its microstructure and mineralogy change with time as the cement gel components recrystallize and react chemically with materials of the repository environment. In principle, the lifetime of this material could be determined based on the study of its long-term behavior, which, in turn, could be estimated from the extrapolation of short-term results, by accelerating, under controlled laboratory conditions, the composition changes and the loss of mechanical strength and cohesion induced by any detrimental component of the repository environment. Loss of mechanical strength, dimensional variations, changes in chemical-mineralogical composition, and leaching of hydrate compounds are all possible

Nuclear fuel element containing strips of an alloyed Zr, Ti, and Ni getter material

International Nuclear Information System (INIS)

Grossman, L.N.; Packard, D.R.

1975-01-01

A nuclear fuel element for use in the core of a nuclear reactor is disclosed. The nuclear fuel element has disposed therein an alloy having the essential components of nickel, titanium and zirconium, and the alloy reacts with water, water vapor and reactive gases at reactor ambient temperatures. The alloy is disposed in the plenum of the fuel element in the form of strips and preferably the strips are positioned inside a helical member in the plenum. The position of the alloy strips permits gases and liquids entering the plenum to contact and react with the alloy strips. (U.S.)

Reacting fluids analysis and polluting emissions; Analisis de fluidos reactivos y emisiones contaminantes

Energy Technology Data Exchange (ETDEWEB)

Munoz Ledo, Ramon; Ley Koo, Marcos [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Varela Ham, Ruben [Universidad Autonoma Metropolitana, Mexico, D. F. (Mexico)

1993-12-31

A problem is set up of a reacting flow which occurs in a gas exhausting duct, which is boiled down to a problem of initial conditions (temperature, pressure and concentration of species) freeing the selection of reaction mechanisms. Through some pre-established algorithms calculation routines can be programmed in specific problems of chemistry kinetics. With the calculation routines set forth in base of the selected mechanism, the temperature, pressure, etc., conditions, a general program is obtained containing the differential equations for the mechanisms, and with its solution, with a certain degree of uncertainty, the gases at a duct outlet can be predicted. The exhaust gases will carry unburned particles and products that can be polluting or not. If we vary the working conditions, we can find the optimum values to work with equipment that produces exhaust gases, anticipating with it the more efficient utilization of the equipment and the energy with the least possible pollution. [Espanol] Se plantea un problema de un flujo reactivo que se lleva a cabo en un ducto de salida de gases de escape, para lo cual se reduce a un problema de condiciones iniciales (temperatura, presion y concentracion de especies), y dejando en libertad la seleccion de mecanismos de reaccion. Mediante algunos algoritmos preestablecidos se pueden programar las rutinas de calculo en problemas especificos de cinetica quimica. Con las rutinas de calculo planteadas en base al mecanismo seleccionado, las condiciones de temperatura, presion, etc. se obtiene un programa general que contiene las ecuaciones diferenciales para el mecanismo y con su solucion se puede predecir con cierto grado de incertidumbre los gases a la salida de un ducto, los gases de salida llevaran particulas inquemadas y productos que pueden ser contaminantes o no, si hacemos variacion en las condiciones de trabajo podemos encontrar los valores optimos para trabajar con equipos que producen gases de escape, previendo con ello

Reacting fluids analysis and polluting emissions; Analisis de fluidos reactivos y emisiones contaminantes

Energy Technology Data Exchange (ETDEWEB)

Munoz Ledo, Ramon; Ley Koo, Marcos [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Varela Ham, Ruben [Universidad Autonoma Metropolitana, Mexico, D. F. (Mexico)

1992-12-31

A problem is set up of a reacting flow which occurs in a gas exhausting duct, which is boiled down to a problem of initial conditions (temperature, pressure and concentration of species) freeing the selection of reaction mechanisms. Through some pre-established algorithms calculation routines can be programmed in specific problems of chemistry kinetics. With the calculation routines set forth in base of the selected mechanism, the temperature, pressure, etc., conditions, a general program is obtained containing the differential equations for the mechanisms, and with its solution, with a certain degree of uncertainty, the gases at a duct outlet can be predicted. The exhaust gases will carry unburned particles and products that can be polluting or not. If we vary the working conditions, we can find the optimum values to work with equipment that produces exhaust gases, anticipating with it the more efficient utilization of the equipment and the energy with the least possible pollution. [Espanol] Se plantea un problema de un flujo reactivo que se lleva a cabo en un ducto de salida de gases de escape, para lo cual se reduce a un problema de condiciones iniciales (temperatura, presion y concentracion de especies), y dejando en libertad la seleccion de mecanismos de reaccion. Mediante algunos algoritmos preestablecidos se pueden programar las rutinas de calculo en problemas especificos de cinetica quimica. Con las rutinas de calculo planteadas en base al mecanismo seleccionado, las condiciones de temperatura, presion, etc. se obtiene un programa general que contiene las ecuaciones diferenciales para el mecanismo y con su solucion se puede predecir con cierto grado de incertidumbre los gases a la salida de un ducto, los gases de salida llevaran particulas inquemadas y productos que pueden ser contaminantes o no, si hacemos variacion en las condiciones de trabajo podemos encontrar los valores optimos para trabajar con equipos que producen gases de escape, previendo con ello

Large eddy simulation of a two-phase reacting swirl flow inside a cement cyclone

International Nuclear Information System (INIS)

Mikulčić, Hrvoje; Vujanović, Milan; Ashhab, Moh'd Sami; Duić, Neven

2014-01-01

This work presents a numerical study of the highly swirled gas–solid flow inside a cement cyclone. The computational fluid dynamics – CFD simulation for continuum fluid flow and heat exchange was used for the investigation. The Eulearian–Lagrangian approach was used to describe the two-phase flow, and the large eddy simulation – LES method was used for correctly obtaining the turbulent fluctuations of the gas phase. A model describing the reaction of the solid phase, e.g. the calcination process, has been developed and implemented within the commercial finite volume CFD code FIRE. Due to the fact that the calcination process has a direct influence on the overall energy efficiency of the cement production, it is of great importance to have a certain degree of limestone degradation at the cyclone's outlet. The heat exchange between the gas and solid phase is of particular importance when studying cement cyclones, as it has a direct effect on the calcination process. In order to study the heat exchange phenomena and the flow characteristics, a three dimensional geometry of a real industrial scroll type cyclone was used for the CFD simulation. The gained numerical results, characteristic for cyclones, such as the pressure drop, and concentration of particles can thus be used for better understanding of the complex swirled two-phase flow inside the cement cyclone and also for improving the heat exchange phenomena. - Highlights: • CFD (computational fluid dynamics) is being increasingly used to enhance efficiency of reacting multi-phase flows. • Numerical model of calcination process was presented. • A detailed industrial geometry was used for the CFD simulation. • Presented model and measurement data are in good agreement

Effect of the properties of natural resin binder in a high friction composite material

Directory of Open Access Journals (Sweden)

S. Stephen Bernard

2014-01-01

Full Text Available In this paper, a high-friction composite material based on the combination of binder, friction modifiers, fibers and fillers is investigated. In the binder, up to 20% of phenol are replaced by cardanol with various weight ratios of 100/0, 95/5, 90/10, 85/15, 80/20. Cardanol may react both through the phenolic group and the double bond of the side chain yielding addition, condensation and polymerisation reactions that allow the synthesis of tailor-made products and polymers of high value. In the present work, mechanical, thermal and wear characteristics of cardanol based phenolic resin with organic ingredients were manufactured and tested. An analysis of microstructure characteristics of composites was carried out using scanning electron microscope. The effect of environment on the composite was investigated in water, salty water and oil. The results showed that the addition of cardanol reduces the wear resistance and increases the compressibility which reduces the noise propensity.

Pressure Dependent Decomposition Kinetics of the Energetic Material HMX up to 3.6 GPa

Energy Technology Data Exchange (ETDEWEB)

Glascoe, E A; Zaug, J M; Burnham, A K

2009-05-29

The effect of pressure on the thermal decomposition rate of the energetic material HMX was studied. HMX was precompressed in a diamond anvil cell (DAC) and heated at various rates. The parent species population was monitored as a function of time and temperature using Fourier transform infrared (FTIR) spectroscopy. Decomposition rates were determined by fitting the fraction reacted to the extended-Prout-Tompkins nucleation-growth model and the Friedman isoconversional method. The results of these experiments and analysis indicate that pressure accelerates the decomposition at low to moderate pressures (i.e. between ambient pressure and 1 GPa) and decelerates the decomposition at higher pressures. The decomposition acceleration is attributed to pressure enhanced autocatalysis whereas the deceleration at high pressures is attributed pressure inhibiting bond homolysis step(s), which would result in an increase in volume. These results indicate that both {beta} and {delta} phase HMX are sensitive to pressure in the thermally induced decomposition kinetics.

Development status of irradiation devices and instrumentation for material and nuclear fuel irradiation tests in HANARO

Energy Technology Data Exchange (ETDEWEB)

Kim, Bong Goo; Sohn, Jae Min; Choo, Kee Nam [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2010-04-15

The High flux Advanced Neutron Application ReactOr (HANARO), an open-tank-in-pool type reactor, is one of the multi-purpose research reactors in the world. Since the commencement of HANARO's operations in 1995, a significant number of experimental facilities have been developed and installed at HANARO, and continued efforts to develop more facilities are in progress. Owing to the stable operation of the reactor and its frequent utilization, more experimental facilities are being continuously added to satisfy various fields of study and diverse applications. The irradiation testing equipment for nuclear fuels and materials at HANARO can be classified into capsules and the Fuel Test Loop (FTL). Capsules for irradiation tests of nuclear fuels in HANARO have been developed for use under the dry conditions of the coolant and materials at HANARO and are now successfully utilized to perform irradiation tests. The FTL can be used to conduct irradiation testing of a nuclear fuel under the operating conditions of commercial nuclear power plants. During irradiation tests conducted using these capsules in HANARO, instruments such as the thermocouple, Linear Variable Differential Transformer (LVDT), small heater, Fluence Monitor (F/M) and Self-Powered Neutron Detector (SPND) are used to measure various characteristics of the nuclear fuel and irradiated material. This paper describes not only the status of HANARO and the status and perspective of irradiation devices and instrumentation for carrying out nuclear fuel and material tests in HANARO but also some results from instrumentation during irradiation tests

Method of making nanostructured glass-ceramic waste forms

Science.gov (United States)

Gao, Huizhen; Wang, Yifeng; Rodriguez, Mark A.; Bencoe, Denise N.

2012-12-18

A method of rendering hazardous materials less dangerous comprising trapping the hazardous material in nanopores of a nanoporous composite material, reacting the trapped hazardous material to render it less volatile/soluble, sealing the trapped hazardous material, and vitrifying the nanoporous material containing the less volatile/soluble hazardous material.

Radioimmunoassay for abscisic acid: properties of cross-reacting polar metabolites

Energy Technology Data Exchange (ETDEWEB)

Le Page-Degivry, M.; Bulard, C. (Faculte des Sciences et des Techniques, 06 - Nice (France))

When the radioimmunoassay developed for abscisic acid (ABA) estimation was applied to a plant extract, results appeared overestimated. Purification by thin-layer chromatography established that ABA in its free and alkali-hydrolysable forms constituted only a small part of the immunoreactive material. The major source of the cross-reactivity was a group of polar metabolites, poorly soluble in ether and well recovered by ethyl acetate and butanol. These immunoreactive metabolites were compared with polar metabolites already described in experiments where (/sup 14/C)ABA was fed to plant tissue, particularly with recently identified glucosides of ABA and dihydrophaseic acid.

Au–Sn bonding material for the assembly of power integrated circuit module

Energy Technology Data Exchange (ETDEWEB)

Zhu, Z.X.; Li, C.C. [Department of Materials Science & Engineering, National Taiwan University, Taipei, Taiwan (China); Liao, L.L.; Liu, C.K. [Electronic and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan (China); Kao, C.R., E-mail: crkao@ntu.edu.tw [Department of Materials Science & Engineering, National Taiwan University, Taipei, Taiwan (China)

2016-06-25

Insulated gate bipolar transistor (IGBT) chips are the key components in high-temperature power electronic modules, which have to efficiently convert electricity between direct and alternating current. In this study, the eutectic Au–Sn (20 wt.% Sn) is successfully used to assemble IGBT chips and direct-bond-copper substrates by using solid liquid interdiffusion (SLID) bonding. During subsequent isothermal aging at 150, 200, and 240 °C, the microstructure evolution and growth kinetics of intermetallic compounds are investigated. Excellent thermal stability and mechanical strength are observed. It is concluded that the eutectic Au–Sn solder is ideal to assemble high-temperature IGBT by using the SLID process. - Highlights: • Au–20Sn serves as a promising bonding material for IGBT operating at T < 519 °C. • The Au–20Sn reacted with Ni to form (Ni,Au){sub 3}Sn{sub 2}/(Au{sub 5}Sn + AuSn)/(Ni,Au){sub 3}Sn{sub 2}. • Once the AuSn was nearly exhausted, the whole joint could withstand higher temperatures. • A cost-effective way for long-term operations at high temperature.

Waste Water Treatment Apparatus and Methods

Science.gov (United States)

Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

2014-01-01

An improved draft tube spout fluid bed (DTSFB) mixing, handling, conveying, and treating apparatus and systems, and methods for operating are provided. The apparatus and systems can accept particulate material and pneumatically or hydraulically conveying the material to mix and/or treat the material. In addition to conveying apparatus, a collection and separation apparatus adapted to receive the conveyed particulate material is also provided. The collection apparatus may include an impaction plate against which the conveyed material is directed to improve mixing and/or treatment. The improved apparatus are characterized by means of controlling the operation of the pneumatic or hydraulic transfer to enhance the mixing and/or reacting by controlling the flow of fluids, for example, air, into and out of the apparatus. The disclosed apparatus may be used to mix particulate material, for example, mortar; react fluids with particulate material; coat particulate material, or simply convey particulate material.

A computer model for one-dimensional mass and energy transport in and around chemically reacting particles, including complex gas-phase chemistry, multicomponent molecular diffusion, surface evaporation, and heterogeneous reaction

Science.gov (United States)

Cho, S. Y.; Yetter, R. A.; Dryer, F. L.

1992-01-01

Various chemically reacting flow problems highlighting chemical and physical fundamentals rather than flow geometry are presently investigated by means of a comprehensive mathematical model that incorporates multicomponent molecular diffusion, complex chemistry, and heterogeneous processes, in the interest of obtaining sensitivity-related information. The sensitivity equations were decoupled from those of the model, and then integrated one time-step behind the integration of the model equations, and analytical Jacobian matrices were applied to improve the accuracy of sensitivity coefficients that are calculated together with model solutions.

Leptospira spp. vaccinal antibodies do not react with Borrelia burgdorferi peptides used in the AccuPlex 4.

Science.gov (United States)

Caress, Amber L; Moroff, Scott; Lappin, Michael R

2017-11-01

We attempted to determine if Leptospira spp. antibodies induced by vaccination would cross-react with Borrelia burgdorferi antigens used in a commercial automated immunofluorescent assay (AccuPlex 4 BioCD; Antech). Staff- and student-owned dogs ( n = 31) were recruited at a veterinary teaching hospital in a B. burgdorferi nonendemic area. The dogs were randomized and administered 1 of 4 commercial Leptospira spp. vaccines that contained serovars Canicola, Grippotyphosa, Icterohaemorrhagiae, and Pomona, then booster vaccinated 3 wk later. Blood was collected on weeks 0, 3, 4, 8, and 12. After confirming that maximal Leptospira spp. titers occurred on week 4, aliquots of sera from week 4 were shipped frozen for analysis of B. burgdorferi antibodies against OspA, OspC, OspF, P39, and SLP with the AccuPlex system. Week 4 sera from all 31 dogs had a titer of 1:100 for at least 1 Leptospira spp. serovar. Titers of 1:800 or greater were detected against multiple serovars in 27 dogs. None of the samples contained antibodies against the B. burgdorferi OspA, OspC, OspF, P39, and SLP peptides used in the commercial assay. The B. burgdorferi peptides used in the AccuPlex system do not recognize naturally occurring Leptospira spp. antibodies or those induced by the commercial Leptospira spp. vaccines administered in our study.

A long-term bench-scale investigation of permanganate consumption by aquifer materials.

Science.gov (United States)

Xu, Xiuyuan; Thomson, Neil R

2009-11-20

of manganese oxide coating on the grains. A long-term NOD kinetic model was developed assuming a single fast and slow reacting oxidizable aquifer material species, passivation of NOD reaction sites, and the presence of an autocatalytic reaction. The developed model was able to successfully capture the observed NOD temporal profiles, and can be used to estimate in situ NOD behavior using batch reactor experimental data. The use of batch tests to provide data representative of in situ conditions should be used with caution.

Study of LiFePO{sub 4} cathode materials coated with high surface area carbon

Energy Technology Data Exchange (ETDEWEB)

Lu, Cheng-Zhang; Fey, George Ting-Kuo [Department of Chemical and Materials Engineering, National Central University, Chung-Li 32054 (China); Kao, Hsien-Ming [Department of Chemistry, National Central University, Chung-Li 32054 (China)

2009-04-01

LiFePO{sub 4} is a potential cathode material for 4 V lithium-ion batteries. Carbon-coated lithium iron phosphates were prepared using a high surface area carbon to react precursors through a solid-state process, during which LiFePO{sub 4} particles were embedded in amorphous carbon. The carbonaceous materials were synthesized by the pyrolysis of peanut shells under argon, where they were carbonized in a two-step process that occurred between 573 and 873 K. The shells were also treated with a proprietary porogenic agent with the goal of altering the pore structure and surface area of the pyrolysis products. The electrochemical properties of the as-prepared LiFePO{sub 4}/C composite cathode materials were systematically characterized by X-ray diffraction, scanning electron microscope, element mapping, energy dispersive spectroscopy, Raman spectroscopy, and total organic carbon (TOC) analysis. In LiFePO{sub 4}/C composites, the carbon not only increases rate capability, but also stabilizes capacity. In fact, the capacity of the composites increased with the specific surface area of carbon. The best result was observed with a composite made of 8.0 wt.% with a specific surface area of 2099 m{sup 2} g{sup -1}. When high surface area carbon was used as a carbon source to produce LiFePO{sub 4}, overall conductivity increased from 10{sup -8} to 10{sup -4} S cm{sup -1}, because the inhibition of particle growth during the final sintering process led to greater specific capacity, improved cycling properties and better rate capability compared to a pure olivine LiFePO{sub 4} material. (author)

Changes in the Chemistry of Groundwater Reacted with CO2: Comparison of Laboratory Results with the ZERT Field Pilot

Science.gov (United States)

Kharaka, Yousif K.; Thordsen, James J.; Abedini, Atosa A.; Beers, Sarah; Thomas, Burt

2017-01-01

As part of the ZERT program, sediments from two wells at the ZERT site, located in Bozeman, Montana, USA were reacted with a solution having the composition of local groundwater. A total of 50 water samples were collected from 7 containers placed for 15 days in a glove box with one atmosphere of CO2 to investigate detailed changes in the concentrations of major, minor and trace inorganic compounds, and to compare these with changes observed in groundwater at the ZERT site following CO2 injection. Laboratory results included rapid changes in pH (8.6 to 5.7), alkalinity (243 to 1295 mg/L as HCO3), electrical conductance (539 to 1822 μS/cm), Ca (28 to 297 mg/L), Mg (18 to 63 mg/L), Fe (5 to 43 μg/L) and Mn (2 to 837 μg/L) following CO2 injection. These chemical changes, which are in general agreement with those obtained from sampling the ZERT monitoring wells, could provide early detection of CO2 leakage into shallow groundwater. Dissolution of calcite, some dolomite and minor Mn-oxides, and desorption/ion exchange are likely the main geochemical processes responsible for the observed changes.

Dictionary materials engineering, materials testing

International Nuclear Information System (INIS)

1994-01-01

This dictionary contains about 9,500 entries in each part of the following fields: 1) Materials using and selection; 2) Mechanical engineering materials -Metallic materials - Non-metallic inorganic materials - Plastics - Composites -Materials damage and protection; 3) Electrical and electronics materials -Conductor materials - Semiconductors - magnetic materials - Dielectric materials - non-conducting materials; 4) Materials testing - Mechanical methods - Analytical methods - Structure investigation - Complex methods - Measurement of physical properties - Non-destructive testing. (orig.) [de

Highly thermal conductive carbon fiber/boron carbide composite material

International Nuclear Information System (INIS)

Chiba, Akio; Suzuki, Yasutaka; Goto, Sumitaka; Saito, Yukio; Jinbo, Ryutaro; Ogiwara, Norio; Saido, Masahiro.

1996-01-01

In a composite member for use in walls of a thermonuclear reactor, if carbon fibers and boron carbide are mixed, since they are brought into contact with each other directly, boron is reacted with the carbon fibers to form boron carbide to lower thermal conductivity of the carbon fibers. Then, in the present invention, graphite or amorphous carbon is filled between the carbon fibers to provide a fiber bundle of not less than 500 carbon fibers. Further, the surface of the fiber bundle is coated with graphite or amorphous carbon to suppress diffusion or solid solubilization of boron to carbon fibers or reaction of them. Then, lowering of thermal conductivity of the carbon fibers is prevented, as well as the mixing amount of the carbon fiber bundles with boron carbide, a sintering temperature and orientation of carbon fiber bundles are optimized to provide a highly thermal conductive carbon fiber/boron carbide composite material. In addition, carbide or boride type short fibers, spherical graphite, and amorphous carbon are mixed in the boron carbide to prevent development of cracks. Diffusion or solid solubilization of boron to carbon fibers is reduced or reaction of them if the carbon fibers are bundled. (N.H.)

Compatibility of ITER candidate structural materials with static gallium

International Nuclear Information System (INIS)

Luebbers, P.R.; Michaud, W.F.; Chopra, O.K.

1993-12-01

Tests were conducted on the compatibility of gallium with candidate structural materials for the International Thermonuclear Experimental Reactor, e.g., Type 316 SS, Inconel 625, and Nb-5 Mo-1 Zr alloy, as well as Armco iron, Nickel 270, and pure chromium. Type 316 stainless steel is least resistant to corrosion in static gallium and Nb-5 Mo-1 Zr alloy is most resistant. At 400 degrees C, corrosion rates are ∼4.0, 0.5, and 0.03 mm/yr for type 316 SS, Inconel 625, and Nb-5 Mo- 1 Zr alloy, respectively. The pure metals react rapidly with gallium. In contrast to findings in earlier studies, pure iron shows greater corrosion than nickel. The corrosion rates at 400 degrees C are ≥88 and 18 mm/yr, respectively, for Armco iron and Nickel 270. The results indicate that at temperatures up to 400 degrees C, corrosion occurs primarily by dissolution and is accompanied by formation of metal/gallium intermetallic compounds. The solubility data for pure metals and oxygen in gallium are reviewed. The physical, chemical, and radioactive properties of gallium are also presented. The supply and availability of gallium, as well as price predictions through the year 2020, are summarized

Multiscale modelling and experimentation of hydrogen embrittlement in aerospace materials

Science.gov (United States)

Jothi, Sathiskumar

Pulse plated nickel and nickel based superalloys have been used extensively in the Ariane 5 space launcher engines. Large structural Ariane 5 space launcher engine components such as combustion chambers with complex microstructures have usually been manufactured using electrodeposited nickel with advanced pulse plating techniques with smaller parts made of nickel based superalloys joined or welded to the structure to fabricate Ariane 5 space launcher engines. One of the major challenges in manufacturing these space launcher components using newly developed materials is a fundamental understanding of how different materials and microstructures react with hydrogen during welding which can lead to hydrogen induced cracking. The main objective of this research has been to examine and interpret the effects of microstructure on hydrogen diffusion and hydrogen embrittlement in (i) nickel based superalloy 718, (ii) established and (iii) newly developed grades of pulse plated nickel used in the Ariane 5 space launcher engine combustion chamber. Also, the effect of microstructures on hydrogen induced hot and cold cracking and weldability of three different grades of pulse plated nickel were investigated. Multiscale modelling and experimental methods have been used throughout. The effect of microstructure on hydrogen embrittlement was explored using an original multiscale numerical model (exploiting synthetic and real microstructures) and a wide range of material characterization techniques including scanning electron microscopy, 2D and 3D electron back scattering diffraction, in-situ and ex-situ hydrogen charged slow strain rate tests, thermal spectroscopy analysis and the Varestraint weldability test. This research shows that combined multiscale modelling and experimentation is required for a fundamental understanding of microstructural effects in hydrogen embrittlement in these materials. Methods to control the susceptibility to hydrogen induced hot and cold cracking and

Evaluation of the new TAMZ titanium alloy for dental cast application.

Science.gov (United States)

Zhang, Y M; Guo, T W; Li, Z C

2000-12-01

To reveal the potential of the new titanium alloy as dental prosthodontic materials. Dental castings of TAMZ alloy were investigated in the casting machine specially designed for titanium. A mesh pattern was used to count the castability value. The mechanical properties were measured by means of a universal testing machine. Optical micrography was done on the exposed cross-section of TAMZ alloy casting. From the surface to the inner part the Knoop hardness in reacted layer of TAMZ alloy casting was measured. The structure and elemental analyses of the reacted layer were made by SEM and element line scanning observation. The castability value (Cv = 98%) and the tensile test (sigma b = 850 Mpa, sigma 0.2 = 575 Mpa, delta = 7.33%) data were collected. The castings microstructure showed main alpha phase and small beta phase. Knoop hardness in the surface reacted layer was greater than that in the inner part. From the SEM and element line scanning observation, there are three different layers in the surface reacted layer of the TAMZ alloy castings, and higher level of element of O, Al, Si and Zr were found in the reacted layer while the Si permeated deeper than others. TAMZ alloy can be accepted as a material for dental alloy in prosthodontics.

Production of magnesium metal

Science.gov (United States)

Blencoe, James G [Harriman, TN; Anovitz, Lawrence M [Knoxville, TN; Palmer, Donald A [Oliver Springs, TN; Beard, James S [Martinsville, VA

2010-02-23

A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention further relates to a process for production of magnesium metal or a magnesium compound where an external source of carbon dioxide is not used in any of the reactions of the process. The invention also relates to the magnesium metal produced by the processes described herein.

Geopolymer resin materials, geopolymer materials, and materials produced thereby

Energy Technology Data Exchange (ETDEWEB)

Seo, Dong-Kyun; Medpelli, Dinesh; Ladd, Danielle; Mesgar, Milad

2018-01-09

A product formed from a first material including a geopolymer resin material, a geopolymer material, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress), thereby forming particles having an external dimension in a range between 1 nm and 2 cm.

Designing Next Generation Rechargeable Battery Materials from First-Principles

Science.gov (United States)

Kim, Soo

interacting with Mn3+ at the (001) LMO surface, promoting an oxidation state change to Mn4+. In addition, we find that graphene defects also react with H2O and generated HF, protecting the active cathode materials from the attack of HF generated in the electrolyte during cycling. The carbonyl and epoxy functional groups in graphene oxide (GO) serve as a physical barrier to mitigate Mn ion dissolution into the liquid electrolyte, stabilizing the overall cell cycling performance. Next, we examine the occurrence of low- and high-temperature LiCoO2 structures and their observed voltage profiles in order to understand the complex structural and electrochemical behaviors. Moreover, a structural search is conducted to identify a new over-lithiated spinel oxide composition, i.e., Fd3¯m LiNi0.8125Co0.1875O2, which may have potential for exploitation in structurally-integrated, 'layered-spinel' cathode system. We have further investigated the structural and electrochemical properties of 'layered-layered-spinel' xLi 2MnO3˙yLiNi0.5Co0.2 Mn0.3O2˙zLiNi0.5Mn 1.5O4 cathode materials using both experiment and theory. Lastly, the idea of a multi-faceted high-throughput (HT) screening approach has been performed within the Open Quantum Materials Database (OQMD) framework to discover possible Li-rich Li2MIO3-Li 2MIIO3 pair combinations (MI,II = elements from the periodic table) that can offer better structural stability, favorable metal-mixing behavior, coherent interfaces, and high energy. Our approach involving computational design of novel materials and systems will accelerate the development of new sustainable energy solutions for meeting global demands.

The electrochemical performance and mechanism of cobalt (II) fluoride as anode material for lithium and sodium ion batteries

International Nuclear Information System (INIS)

Tan, Jinli; Liu, Li; Guo, Shengping; Hu, Hai; Yan, Zichao; Zhou, Qian; Huang, Zhifeng; Shu, Hongbo; Yang, Xiukang; Wang, Xianyou

2015-01-01

Highlights: •The as-prepared CoF 2 shows excellent electrochemical performance as anode material for lithium ion batteries. •The Li insertion/extraction mechanism of CoF 2 below 1.2 V was firstly proposed. •The electrochemical performance of CoF 2 as anode material in sodium ion batteries was firstly studied. -- Abstract: Cobalt (II) fluoride begins to enter into the horizons of people along with the research upsurge of metal fluorides. It is very significative and theoretically influential to make certain its electrochemical reaction mechanism. In this work, we discover a new and unrevealed reversible interfacial intercalation mechanism reacting below 1.2 V for cobalt (II) fluoride electrode material, which contributes a combined discharge capacity of about 400 mA h g −1 with the formation of SEI film at the initial discharge process. A highly reversible storage capacity of 120 mA h g −1 is observed when the cell is cycled over the voltage of 0.01-1.2 V at 0.2 C, and the low-potential voltage reaction process has a significant impact for the whole electrochemical process. Electrochemical analyses suggest that pure cobalt (II) fluoride shows better electrochemical performance when it is cycled at 3.2-0.01 V compared to the high range (1.0-4.5 V). So, we hold that cobalt (II) fluoride is more suitable to serve as anode material for lithium ion batteries. In addition, we also try to reveal the relevant performance and reaction mechanism, and realize the possibility of cobalt (II) fluoride as anode material for sodium ion batteries

Monoclonal antibody against a serotype antigen of Porphyromonas (Bacteroides) endodontalis and characteristics of the antigen.

Science.gov (United States)

Hanazawa, S; Sagiya, T; Amano, S; Nishikawa, H; Kitano, S

1990-01-01

Recent studies have demonstrated the presence of three serotypes (O1K1, O1K2, and O1K-) of Porphyromonas (Bacteroides) endodontalis. In the present study, a hybridoma cell line producing monoclonal antibody (BEE11) specific for serotype O1K1 of P. endodontalis was established. The specificity of the antibody was evaluated by enzyme-linked immunosorbent assay and immunoslot blot analysis. BEE11 antibody reacted with strains ATCC 35406, HG 400, and HG 421 of the bacterium. However, it did not react with HG 422 or HG 948. Also, the antibody did not react with any of the black-pigmented Bacteroides strains tested. Although the antibody reacted with total cell envelope and capsule materials, it did not do so with lipopolysaccharide. The antibody reacted with antigen material having a molecular mass of 110 kilodaltons (kDa), as judged from fractionation by Superose 12 prep gel chromatography. When the peak fraction from the Superose 12 column was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) analysis, the reactivity was detected as a single band at an apparent molecular mass of about 52 kDa. The antigen material purified partially by high-performance liquid chromatography was sensitive to trypsin, V8 protease, and heating to 80 degrees C but not to neuraminidase. Therefore, the present study shows that BEE11 antibody recognizes a serotype antigen of P. endodontalis which may be a dimer consisting of monomers having molecular masses of approximately 52 kDa and sensitivity to proteases and heat. Images PMID:2370106

Could Regulator Materialize Potential Demand for Islamic Securities? Evidence from Indonesia

Directory of Open Access Journals (Sweden)

Bayu Kariastanto

2012-01-01

Full Text Available Objective – The objective of this paper is to provide a discussion whether Islamic securities enjoy larger demands than conventional securities. This paper also investigate whether regulator could effectively take a role in materializing demands for Islamic securities and whether regulator declaration is more convincing than sharia compliance declaration by another institution.Methods - We employ differences in differences (DID regression to see the immediate, medium, and long term market response to this announcement. We also estimate cumulative abnormal returns by employing the standard market model for the robustness test.Results - We find that market reacts to sharia compliance declaration by regulator in the long-run, hence potential demands are realized and the Islamic securities will enjoy greater market power. We also provide evidence that Islamic investors are not too strict in screening Islamic securities and are willing to accept different opinions regarding sharia compliance.Conclusion - This finding could explain why Islamic finance is still growing rapidly even though there are critiques in the genuineness of sharia compliance of the current Islamic financial products/services.Keywords: Regulator, Islamic securities, sharia compliance, demand, investor confidence

Geopolymer resin materials, geopolymer materials, and materials produced thereby

Science.gov (United States)

Seo, Dong-Kyun; Medpelli, Dinesh; Ladd, Danielle; Mesgar, Milad

2016-03-29

A product formed from a first material including a geopolymer resin material, a geopolymer resin, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress), thereby forming particles having an external dimension in a range between 1 nm and 2 cm.

Mixing and NO(x) Emission Calculations of Confined Reacting Jet Flows in a Cylindrical Duct

Science.gov (United States)

Holdeman, James D. (Technical Monitor); Oechsle, Victor L.

2003-01-01

Rapid mixing of cold lateral jets with hot cross-stream flows in confined configurations is of practical interest in gas turbine combustors as it strongly affects combustor exit temperature quality, and gaseous emissions in for example rich-lean combustion. It is therefore important to further improve our fundamental understanding of the important processes of dilution jet mixing especially when the injected jet mass flow rate exceeds that of the cross-stream. The results reported in this report describe some of the main flow characteristics which develop in the mixing process in a cylindrical duct. A 3-dimensional tool has been used to predict the mixing flow field characteristics and NOx emission in a quench section of an RQL combustor, Eighteen configurations have been analyzed in a circular geometry in a fully reacting environment simulating the operating condition of an actual RQL gas turbine combustion liner. The evaluation matrix was constructed by varying three parameters: 1) jet-to-mainstream momentum-flux ratio (J), 2) orifice shape or orifice aspect ratio, and 3) slot slant angle. The results indicate that the mixing flow field significantly varies with the value of the jet penetration and subsequently, slanting elongated slots generally improve the mixing uniformity at high J conditions. Round orifices produce more uniform mixing and low NO(x) emissions at low J due to the strong and adequate jet penetration. No significant correlation was found between the NO(x) production rates and the mixing deviation parameters, however, strong correlation was found between NO(x) formation and jet penetration. In the computational results, most of the NO(x) formation occurred behind the orifice starting at the orifice wake region. Additional NO(x) is formed upstream of the orifice in certain configurations with high J conditions due to the upstream recirculation.

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

... where MM′ represents MnMn, CoMn, NiMn, CuMn, CoCo, NiCo, CuCo, NiNi, CuNi, and CuCu; and the respective complexes, numbered 1–10, have been prepared by reacting metal(II) salts—i.e. of Mn, Co, Ni, and Cu—and potassium oxalate monohydrate in hot water (90–100°C). The magnetic susceptibility data of the ...

Cross-reacting Material-positive Hemophilia A Diagnosed in a Patient with a Spontaneous Thigh Hemorrhage.

Science.gov (United States)

Saito, Tatsuya; Mukae, Jyunichi; Nakamura, Yosuke; Inaba, Hiroshi; Nogami, Keiji; Koyama, Takatoshi; Fukutake, Katsuyuki; Yamamoto, Koh

2017-01-01

A 53-year-old man, who had been diagnosed with mild hemophilia A (HA) at 35 years of age, was hospitalized with a thigh hematoma. His bleeding continued despite the administration of recombinant factor VIII (FVIII). The results of an FVIII/von Willebrand factor binding assay were normal. The patient's FVIII coagulant activity (FVIII:C) was low, but his FVIII antigen levels were within the normal limits, suggesting FVIII protein dysfunction. The FVIII:C measurements obtained by one-stage clotting and chromogenic assays were different. An FVIII gene analysis revealed a missense mutation p.Ser308Leu, which is rare in Japan. This case highlights that gene analyses and chromogenic assays are necessary to interpret the discrepancies between FVIII:C and the bleeding phenotype of patients with mild HA.

Integrated Reacting Fluid Dynamics and Predictive Materials Degradation Models for Propulsion System Conditions, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Computational fluid dynamics (CFD) simulations are routinely used by NASA to optimize the design of propulsion systems. Current methods for CFD modeling rely on...

Connection of a He-jet recoil transport system to an ion source

International Nuclear Information System (INIS)

Sheppard, G.A.

1977-02-01

In an effort to make non-gaseous fission products available for on-line separation and study with the TRISTAN facility, an investigation of the operational characteristics of a He-jet recoil transport system and a TRISTAN-type ion source was conducted after interfacing them with a skimmer. So that experimental results could be understood and controlled, studies of the dynamics of choked flow in a capillary and of the transport characteristics were made. Satisfactory performance of the He-jet system was obtained, but large temperature and pressure gradients thwarted early attempts to efficiently couple the He-jet to the ion source. The pressure-related difficulties have been overcome by employing a skimmer to remove extraneous gases before injection of the activities into the ion source, but efforts to conquer the temperature-related problems continue

Recycling of Pre-Washed Municipal Solid Waste Incinerator Fly Ash in the Manufacturing of Low Temperature Setting Geopolymer Materials.

Science.gov (United States)

Ferone, Claudio; Colangelo, Francesco; Messina, Francesco; Santoro, Luciano; Cioffi, Raffaele

2013-08-12

In this work, three samples of municipal solid waste incinerators fly ash (MSWI-FA) have been stabilized in systems containing coal fly ash to create geopolymers through a polycondensation reaction. Monolithic products have been obtained with both MSWI fly ash as received and after the partial removal of chloride and sulfate by water washing. The polycondensation products have been characterized qualitatively by means of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy and quantitatively, through the determination of the volume of reacted water and silicate. Furthermore, the heavy metals and chloride releases together with the physico-mechanical properties have been evaluated on the hardened products. In conclusion, considering the technological and environmental performances of the obtained geopolymers, they could be suitable for many non-structural applications, such as backfilling of abandoned quarries, decorative materials or brick fireplaces, hearths, patios, etc.

Material Development Study for a Hazardous Chemical Protective Clothing Outfit

Science.gov (United States)

1980-08-01

Analytical - X VCM Vinyl Chloride Unavailable - X ZEC Zectran Insoluble X X ZCN Zinc Cyanide Insoluble X X ZCT Zirconium Tetrachloride Water React. X 64...Environmental Rating of Plastics, Reprints of Design News, R. L. Peters , 6 December 1967, 20 December 1967, 22 November 1967, 8 November 1967. 13. Modern

The Noell Conversion Process - a gasification process for the pollutant-free disposal of sewage sludge and the recovery of energy and materials

Energy Technology Data Exchange (ETDEWEB)

Jaeger, M. [Preussag Noell GmbH, Wuerzburg (Germany); Mayer, M. [Noell-KRC Energie- und Umwelttechnik GmbH, Wuerzburg (Germany)

2000-07-01

The Noell Conversion Process was developed to guarantee the safe disposal of sewage sludge and other waste materials by means of thermal treatment, even with every strict emission standards. The center piece of this process is a pressurised entrained flow gasifier. The reacting conditions in this gasifier does not only suppresses the formation of dioxins and furans, but also completely destroys and dioxins and furans contained in the waste materials. Another advantage of the Noell Conversion Process referring the thermal treatment of sewage sludge is the recovery of marketable substances such as synthesis gas, sulphur and vitrified slag. To demonstrate this advanced technology in the field of sewage sludge treatment, Noell-KRC has built a pilot plant in Freiberg/Germany. This plant was designed for a throughput of 0.5 Mg/h (dry base) of sewage sludge. During the operation of the plant from 1996 until 1998, it was possible to demonstrate that there are no problems with emissions of heavy metals like Mercury or organic components like Dioxins and Furans. The H2 rich gas produced in the process can be utilised as a power source. The vitrified slag produced in the process is of a quality suitable for use as a construction material with a wide range of applications. (Author)

Carbon fiber CVD coating by carbon nanostructured for space materials protection against atomic oxygen

Science.gov (United States)

Pastore, Roberto; Bueno Morles, Ramon; Micheli, Davide

2016-07-01

In recent years, the emphasis in space research has been shifting from space exploration to commercialization of space. In order to utilize space for commercial purposes it is necessary to understand the low earth orbit (LEO) space environment where most of the activities will be carried out. The studies on the LEO environment are mainly focused towards understanding the effect of atomic oxygen (AO) on spacecraft materials. In the first few shuttle flights, materials looked frosty because they were actually being eroded and textured: AO reacts with organic materials on spacecraft exteriors, gradually damaging them. When a spacecraft travel in LEO (where crewed vehicles and the International Space Station fly), the AO formed from the residual atmosphere can react with the spacecraft surfaces, causing damage to the vehicle. Polymers are widely used in space vehicles and systems as structural materials, thermal blankets, thermal control coatings, conformal coatings, adhesives, lubricants, etc. Exposure of polymers and composites to the space environment may result in different detrimental effects via modification of their chemical, electrical, thermal, optical and mechanical properties as well as surface erosion. The major degradation effects in polymers are due to their exposure to atomic oxygen, vacuum ultraviolet and synergistic effects, which result in different damaging effects by modification of the polymer's chemical properties. In hydrocarbon containing polymers the main AO effect is the surface erosion via chemical reactions and the release of volatile reaction products associated with the mass loss. The application of a thin protective coating to the base materials is one of the most commonly used methods of preventing AO degradation. The purpose is to provide a barrier between base material and AO environment or, in some cases, to alter AO reactions to inhibit its diffusion. The effectiveness of a coating depends on its continuity, porosity, degree of

Material Capability for Transport of Unsymmetrical Dimethylhydrazine

Science.gov (United States)

1990-07-13

is shown in Figure 1. The air supply was house compressed air conditioned by passing it through a series of demisters, a hot Hopcalite catalyst bed...required to reach that value was recorded. At the end of a test, the tubing was rinsed with methanol and dried with compressed breathing air or filtered... compressed house air . Solvents such as acetone were not used as they react with hydrazines (8]. Table 2 lists the combinations of tubing length, UDMH or

Effects of polishing on surface roughness, gloss and color of surface reaction type pre-reacted glass-ionomer filled resin composite.

Science.gov (United States)

Hosoya, Yumiko; Shiraishi, Takanobu; Odatsu, Tetsuro; Miyazaki, Masashi; García-Godoy, Franklin

2011-06-01

To evaluate the effects of polishing on surface roughness, gloss and color of different shades of surface reaction type pre-reacted glass-ionomer (S-PRG) filled nano-hybrid resin composite. Resin disks of 15 mm diameter and 2 mm thickness and final polish with 1000-grit SiC paper, super fine cut diamond (FG) point, silicon (MFR) point and Super-Snap mini-disk red (SNAP) were made with Beautifil II shades: A2, A20, Inc). One week after curing, the surface roughness, gloss and color were measured. Data was analyzed with ANOVA and Fisher's PLSD with alpha= 0.05 For all shades, the order of roughness (Ra) ranked according to groups of 1000-grit SiC > FG > MFR > SNAP with significant differences among all groups. For all shades, the order of gloss ranked according to groups of SNAP > MFR > FG > 1000-grit SiC with significant differences among the groups except for between MFR and FG without significant difference. The influence of the surface roughness on color differed among the polishing groups and shades. However, the values of the color differences (deltaE*ab) between the polishing groups of all shades were imperceptible to the naked eye.

Further important sensitizers in patients sensitive to fragrances

DEFF Research Database (Denmark)

Frosch, P J; Johansen, Jeanne Duus; Menné, T

2002-01-01

The aim of this study was to determine the frequency of responses to selected fragrance materials in consecutive patients patch tested in 6 dermatological centres in Europe. 1855 patients were evaluated with the 8% fragrance mix (FM) and 14 other frequently used well-defined fragrance chemicals.......5%), citronellol (0.4%), hexyl cinnamic aldehyde (0.3%), and coumarin (0.3%). 41 (2.2%) of the patients reacted only to materials of series I and not to FM. 6.6% of 1855 patients gave a history of adverse reactions to fragrances which was classified as certain. This group reacted to FM only in 41.1%, to series I...... and FM in 12.0% and to series I only in 7.2%. 74.3% of the 39 patients reacting to both FM and 1 of the materials of series I had any type of positive fragrance history, which was significantly higher in comparison to those with isolated reactions to series I (53.6% of 41), p = 0.04. The study identified...

Semi-implicit iterative methods for low Mach number turbulent reacting flows: Operator splitting versus approximate factorization

Science.gov (United States)

MacArt, Jonathan F.; Mueller, Michael E.

2016-12-01

Two formally second-order accurate, semi-implicit, iterative methods for the solution of scalar transport-reaction equations are developed for Direct Numerical Simulation (DNS) of low Mach number turbulent reacting flows. The first is a monolithic scheme based on a linearly implicit midpoint method utilizing an approximately factorized exact Jacobian of the transport and reaction operators. The second is an operator splitting scheme based on the Strang splitting approach. The accuracy properties of these schemes, as well as their stability, cost, and the effect of chemical mechanism size on relative performance, are assessed in two one-dimensional test configurations comprising an unsteady premixed flame and an unsteady nonpremixed ignition, which have substantially different Damköhler numbers and relative stiffness of transport to chemistry. All schemes demonstrate their formal order of accuracy in the fully-coupled convergence tests. Compared to a (non-)factorized scheme with a diagonal approximation to the chemical Jacobian, the monolithic, factorized scheme using the exact chemical Jacobian is shown to be both more stable and more economical. This is due to an improved convergence rate of the iterative procedure, and the difference between the two schemes in convergence rate grows as the time step increases. The stability properties of the Strang splitting scheme are demonstrated to outpace those of Lie splitting and monolithic schemes in simulations at high Damköhler number; however, in this regime, the monolithic scheme using the approximately factorized exact Jacobian is found to be the most economical at practical CFL numbers. The performance of the schemes is further evaluated in a simulation of a three-dimensional, spatially evolving, turbulent nonpremixed planar jet flame.

Broadcasting, Reacting, Engaging

DEFF Research Database (Denmark)

Etter, Michael

2014-01-01

Purpose - Symmetric communication and relationship building are core principles of public relations, which have been highlighted for CSR communication. In this paper three different communication strategies for CSR communication in Twitter are developed, of which each contributes differently...... to the ideals of symmetric communication and relationship building. The framework is then applied to analyze how companies use the micro-blogging service Twitter for CSR communication. Design/methodology/approach - Social network analysis is used to identify the 30 most central corporate accounts in a CSR...... Twitter-Network. From these accounts over 40´000 tweets are extracted and manually coded. Anova is applied to investigate differences in the weighting of CSR topics between the different strategies. Findings - The analysis reveals that corporations adhere to a broadcasting strategy or a reactive strategy...

Solid Liquid Interdiffusion Bonding of Zn4Sb3 Thermoelectric Material with Cu Electrode

Science.gov (United States)

Lin, Y. C.; Lee, K. T.; Hwang, J. D.; Chu, H. S.; Hsu, C. C.; Chen, S. C.; Chuang, T. H.

2016-10-01

The ZnSb intermetallic compound may have thermoelectric applications because it is low in cost and environmentally friendly. In this study, a Zn4Sb3 thermoelectric element coated with a Ni barrier layer and a Ag reaction layer was bonded with a Ag-coated Cu electrode using a Ag/Sn/Ag solid-liquid interdiffusion bonding process. The results indicated that a Ni5Zn21 intermetallic phase formed easily at the Zn4Sb3/Ni interface, leading to sound adhesion. In addition, Sn film was found to react completely with the Ag layer to form a Ag3Sn intermetallic layer having a melting point of 480°C. The resulting Zn4Sb3 thermoelectric module can be applied at the optimized operation temperature (400°C) of Zn4Sb3 material as a thermoelectric element. The bonding strengths ranged from 14.9 MPa to 25.0 MPa, and shear tests revealed that the Zn4Sb3/Cu-joints fractured through the interior of the thermoelectric elements.

Process for forming a homogeneous oxide solid phase of catalytically active material

Science.gov (United States)

Perry, Dale L.; Russo, Richard E.; Mao, Xianglei

1995-01-01

A process is disclosed for forming a homogeneous oxide solid phase reaction product of catalytically active material comprising one or more alkali metals, one or more alkaline earth metals, and one or more Group VIII transition metals. The process comprises reacting together one or more alkali metal oxides and/or salts, one or more alkaline earth metal oxides and/or salts, one or more Group VIII transition metal oxides and/or salts, capable of forming a catalytically active reaction product, in the optional presence of an additional source of oxygen, using a laser beam to ablate from a target such metal compound reactants in the form of a vapor in a deposition chamber, resulting in the deposition, on a heated substrate in the chamber, of the desired oxide phase reaction product. The resulting product may be formed in variable, but reproducible, stoichiometric ratios. The homogeneous oxide solid phase product is useful as a catalyst, and can be produced in many physical forms, including thin films, particulate forms, coatings on catalyst support structures, and coatings on structures used in reaction apparatus in which the reaction product of the invention will serve as a catalyst.

A radioimmunoassay for abscisic acid: properties of cross-reacting polar metabolites

International Nuclear Information System (INIS)

Le Page-Degivry, M.; Bulard, C.

1984-01-01

When the radioimmunoassay developed for abscisic acid (ABA) estimation was applied to a plant extract, results appeared overestimated. Purification by thin-layer chromatography established that ABA in its free and alkali-hydrolysable forms constituted only a small part of the immunoreactive material. The major source of the cross-reactivity was a group of polar metabolites, poorly soluble in ether and well recovered by ethyl acetate and butanol. These immunoreactive metabolites were compared with polar metabolites already described in experiments wher e [ 14 C]ABA was fed to plant tissue, particularly with recently identified glucosides of ABA and dihydrophaseic acid

COARSE-GRID SIMULATION OF REACTING AND NON-REACTING GAS-PARTICLE FLOWS

Energy Technology Data Exchange (ETDEWEB)

Sankaran Sundaresan

2004-03-01

The principal goal of this project, funded under the ''DOE Vision 21 Virtual Demonstration Initiative'' is virtual demonstration of circulating fluidized bed performance. We had proposed a ''virtual demonstration tool'', which is based on the open-domain CFD code MFIX. The principal challenge funded through this grant is to devise and implement in this CFD code sound physical models for the rheological characteristics of the gas-particle mixtures. Within the past year, which was the third year of the project, we have made the following specific advances. (a) We have completed a study of the impact of sub-grid models of different levels of detail on the results obtained in coarse-grid simulations of gas-particle flow. (b) We have also completed a study of a model problem to understand the effect of wall friction, which was proved in our earlier work to be very important for stable operation of standpipes in a circulating fluidized bed circuit. These are described in a greater detail in this report.

Dependence and withdrawal reactions to benzodiazepines and selective serotonin reuptake inhibitors. How did the health authorities react?

Science.gov (United States)

Nielsen, Margrethe; Hansen, Ebba Holme; Gøtzsche, Peter C

2013-01-01

Our objective was to explore communications from drug agencies about benzodiazepine dependence and selective serotonin reuptake inhibitors (SSRIs) withdrawal reactions over time. Documentary study. We searched the web-sites of the European Medicines Agency and the drug agencies in USA, UK, and Denmark for documents mentioning benzodiazepines or SSRIs. We supplemented with other relevant literature that could contribute to our study. The searches were performed in 2009 in PubMed, Google, BMJ and JAMA. It took many years before the drug regulators acknowledged benzodiazepine dependence and SSRI withdrawal reactions and before the prescribers and the public were informed. Drug regulators relied mainly on the definitions of dependence and withdrawal reactions from the diagnostic psychiatric manuals, which contributed to the idea that SSRIs do not cause dependence, although it is difficult for many patients to stop treatment. In the perspective of a precautionary principle, drug agencies have failed to acknowledge that SSRIs can cause dependence and have minimised the problem with regard to its frequency and severity. In the perspective of a risk management principle, the drug agencies have reacted in concordance with the slowly growing knowledge of adverse drug reactions and have sharpened the information to the prescribers and the public over time. However, solely relying on spontaneous reporting of adverse effects leads to underestimation and delayed information about the problems. Given the experience with the benzodiazepines, we believe the regulatory bodies should have required studies from the manufacturers that could have elucidated the dependence potential of the SSRIs before marketing authorization was granted.

Functional polyester materials with tunable degradability: Investigations into the use of reductive amination, ketoxime ether, and hydrazone linkages for functionalization, covalent stabilization and crosslinking of poly(epsilon-caprolactone) materials

Science.gov (United States)

van Horn, Brooke Angela

Aliphatic polyesters represent one class of degradable, polymeric materials that is receiving significant attention in the search for, and design of, biocompatible and bioresorbable synthetic substances. Functional and crosslinked polyesters, having potential biomedical value, are the target of many avenues of current research. This dissertation work expands the utility of a specific aliphatic polyester, poly(epsilon-caprolactone-co-2-oxepane-1,5-dione) (P(CL-co-OPD)), which contains backbone ketone units that can be reacted with various functional, nucleophilic agents. Results presented in this dissertation convey both the successes had and the challenges encountered in the employment of different "iminyl" chemistries for the synthesis of functional and crosslinked materials. Specifically, the ketone-functionalized polyester was investigated as a general substrate designed to undergo solution-state intramolecular crosslinking and functionalization upon reductive amination with 1,6-hexanediamine and hexylamine, respectively, in the presence of NaCNBH3. Through detailed analysis of the products from these reactions, and simpler systems including small molecule model compounds, the polymeric gamma-keto ester functionality was determined to be incompatible with the reductive amination chemistry, resulting in chain cleavage via intramolecular lactam formation. Subsequent investigation of ketoxime ether formation using synthetic model hydroxylamines, 1-aminooxydodecane and 1,6-bis(aminooxy)hexane, in solution and in the presence of an acid catalyst, resulted in the targeted graft and crosslinked particulate/gel materials, respectively. With the significant interest in the development of synthetic polymer materials of increasing degrees of complexity, attention has been focused on the efficient and high-yielding conversion of polyesters into multi-functional materials. Facile conjugation of aminooxy- and sulfonyl hydrazide model ligands with P(CL-co-OPD) were also

Hydration characteristics of zirconium oxide replaced Portland cement for use as a root-end filling material.

Science.gov (United States)

Camilleri, J; Cutajar, A; Mallia, B

2011-08-01

cement. A prototype dental material composed of Portland cement replaced with 30% zirconium oxide as radiopacifier leached calcium ions on hydration which reacted with phosphates present in simulated tissue fluids. This resulted in bioactive cement that could prospectively be used as a root-end filling material. The zirconium oxide acted as inert filler and did not participate in the hydration reaction of the Portland cement. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Recycling of Pre-Washed Municipal Solid Waste Incinerator Fly Ash in the Manufacturing of Low Temperature Setting Geopolymer Materials

Directory of Open Access Journals (Sweden)

Raffaele Cioffi

2013-08-01

Full Text Available In this work, three samples of municipal solid waste incinerators fly ash (MSWI-FA have been stabilized in systems containing coal fly ash to create geopolymers through a polycondensation reaction. Monolithic products have been obtained with both MSWI fly ash as received and after the partial removal of chloride and sulfate by water washing. The polycondensation products have been characterized qualitatively by means of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy and quantitatively, through the determination of the volume of reacted water and silicate. Furthermore, the heavy metals and chloride releases together with the physico-mechanical properties have been evaluated on the hardened products. In conclusion, considering the technological and environmental performances of the obtained geopolymers, they could be suitable for many non-structural applications, such as backfilling of abandoned quarries, decorative materials or brick fireplaces, hearths, patios, etc.

Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

International Nuclear Information System (INIS)

J.P. Nicot

2000-01-01

The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the WP. This

Aerospace materials and material technologies

CERN Document Server

Wanhill, R

2017-01-01

This book is a comprehensive compilation of chapters on materials (both established and evolving) and material technologies that are important for aerospace systems. It considers aerospace materials in three Parts. Part I covers Metallic Materials (Mg, Al, Al-Li, Ti, aero steels, Ni, intermetallics, bronzes and Nb alloys); Part II deals with Composites (GLARE, PMCs, CMCs and Carbon based CMCs); and Part III considers Special Materials. This compilation has ensured that no important aerospace material system is ignored. Emphasis is laid in each chapter on the underlying scientific principles as well as basic and fundamental mechanisms leading to processing, characterization, property evaluation and applications. A considerable amount of materials data is compiled and presented in appendices at the end of the book. This book will be useful to students, researchers and professionals working in the domain of aerospace materials.

Novel synthesis on poly (vinyl alcohol): characterization, complexation a biological activity

International Nuclear Information System (INIS)

El-Sawy, N.M.; Elassar, A.Z.; Al-Fulaij, O.

2002-01-01

Poly(vinyl alcohol), PVA, readily condensed with phenyl hydrazine and malononitrile in basic medium to give the hydrazone and pyran derivatives, respectively. PVA reacted with chloroacetonitrile, biuet and thiophene carbonyl chloride to give modified polymeric materials. While addition of PVA to acrylonitrile and phenyl isothiocyanate gives the ether and thiocarbamate ester derivatives, respectively. Hydroxylamine hydrochloride reacted with the modified, carbonitrile containing, polymer to give the amidoxime derivative. The amidoximated products of PVA and carbamate ester of polymeric material were complexed with CUCL2 solution. The complex materials were confirmed by using UV and ESDS measurements. The morphology of PVA and complex with CUII was observed by SEM. Biological activity of some of the prepared compounds was investigated toward bacteria and fungi

METHOD OF IMPREGNATING A POROUS MATERIAL

Science.gov (United States)

Steele, G.N.

1960-06-01

A method of impregnating a porous body with an inorganic uranium- containing salt is outlined and comprises dissolving a water-soluble uranium- containing salt in water; saturating the intercommunicating pores of the porous body with the salt solution; infusing ammonia gas into the intercommunicating pores of the body, the ammonia gas in water chemically reacting with the water- soluble uranium-containing salt in the water solvent to form a nonwater-soluble uranium-containing precipitant; and evaporating the volatile unprecipitated products from the intercommunicating pores whereby the uranium-containing precipitate is uniformly distributed in the intercommunicating peres of the porous body.

Preparation of Silica Nanoparticles and Its Beneficial Role in Cementitious Materials

Directory of Open Access Journals (Sweden)

S. Ahalawat

2011-07-01

Full Text Available Spherical silica nanoparticles (n‐SiO2 with controllable size have been synthesized using tetraethoxysilane as starting material and ethanol as solvent by sol‐gel method. Morphology and size of the particles was controlled through surfactants. Sorbitan monolaurate, sorbitain monopalmitate and sorbitain monostearate produced silica nanoparticles of varying sizes (80‐150 nm, indicating the effect of chain length of the surfactant. Increase in chain length of non‐ionic surfactant resulted in decreasing particle size of silica nanoparticles. Further, the size of silica particles was also controlled using NH3 as base catalyst. These silica nanoparticles were incorporated into cement paste and their role in accelerating the cementitious reactions was investigated. Addition of silica nanoparticles into cement paste improved the microstructure of the paste and calcium leaching is significantly reduced as n‐SiO2 reacts with calcium hydroxide and form additional calcium‐ silicate‐hydrate (C‐S‐H gel. It was found that calcium hydroxide content in silica nanoparticles incorporated cement paste reduced ~89% at 1 day and up to ~60% at 28 days of hydration process. Synthesized silica particles and cement paste samples were characterized using scanning electron microscopy (SEM, powder X‐ray diffraction (XRD, infrared spectroscopy (IR and thermogravimetric analysis (TGA.

Formation of CaB6 in the thermal decomposition of the hydrogen storage material Ca(BH4)2.

Science.gov (United States)

Sahle, Christoph J; Sternemann, Christian; Giacobbe, Carlotta; Yan, Yigang; Weis, Christopher; Harder, Manuel; Forov, Yury; Spiekermann, Georg; Tolan, Metin; Krisch, Michael; Remhof, Arndt

2016-07-20

Using a combination of high resolution X-ray powder diffraction and X-ray Raman scattering spectroscopy at the B K- and Ca L2,3-edges, we analyzed the reaction products of Ca(BH4)2 after annealing at 350 °C and 400 °C under vacuum conditions. We observed the formation of nanocrystalline/amorphous CaB6 mainly and found only small contributions from amorphous B for annealing times larger than 2 h. For short annealing times of 0.5 h at 400 °C we observed neither CaB12H12 nor CaB6. The results indicate a reaction pathway in which Ca(BH4)2 decomposes to B and CaH2 and finally reacts to form CaB6. These findings confirm the potential of using Ca(BH4)2 as a hydrogen storage medium and imply the desired cycling capabilities for achieving high-density hydrogen storage materials.

Transmutation detectors

Energy Technology Data Exchange (ETDEWEB)

Viererbl, L., E-mail: vie@ujv.c [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Lahodova, Z. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Klupak, V. [Nuclear Research Institute Rez plc (Czech Republic); Sus, F. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic); Kucera, J. [Research Centre Rez Ltd. (Czech Republic); Nuclear Physics Institute, Academy of Sciences of the Czech Republic (Czech Republic); Kus, P.; Marek, M. [Research Centre Rez Ltd. (Czech Republic); Nuclear Research Institute Rez plc (Czech Republic)

2011-03-11

We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

Transmutation detectors

International Nuclear Information System (INIS)

Viererbl, L.; Lahodova, Z.; Klupak, V.; Sus, F.; Kucera, J.; Kus, P.; Marek, M.

2011-01-01

We have designed a new type of detectors, called transmutation detectors, which can be used primarily for neutron fluence measurement. The transmutation detector method differs from the commonly used activation detector method in evaluation of detector response after irradiation. Instead of radionuclide activity measurement using radiometric methods, the concentration of stable non-gaseous nuclides generated by transmutation in the detector is measured using analytical methods like mass spectrometry. Prospective elements and nuclear reactions for transmutation detectors are listed and initial experimental results are given. The transmutation detector method could be used primarily for long-term measurement of neutron fluence in fission nuclear reactors, but in principle it could be used for any type of radiation that can cause transmutation of nuclides in detectors. This method could also be used for measurement in accelerators or fusion reactors.

Lie Group Solution for Free Convective Flow of a Nanofluid Past a Chemically Reacting Horizontal Plate in a Porous Media

Directory of Open Access Journals (Sweden)

M. M. Rashidi

2014-01-01

Full Text Available The optimal homotopy analysis method (OHAM is employed to investigate the steady laminar incompressible free convective flow of a nanofluid past a chemically reacting upward facing horizontal plate in a porous medium taking into account heat generation/absorption and the thermal slip boundary condition. Using similarity transformations developed by Lie group analysis, the continuity, momentum, energy, and nanoparticle volume fraction equations are transformed into a set of coupled similarity equations. The OHAM solutions are obtained and verified by numerical results using a Runge-Kutta-Fehlberg fourth-fifth order method. The effect of the emerging flow controlling parameters on the dimensionless velocity, temperature, and nanoparticle volume fraction have been presented graphically and discussed. Good agreement is found between analytical and numerical results of the present paper with published results. This close agreement supports our analysis and the accuracy of the numerical computations. This paper also includes a representative set of numerical results for reduced Nusselt and Sherwood numbers in a table for various values of the parameters. It is concluded that the reduced Nusselt number increases with the Lewis number and reaction parameter whist it decreases with the order of the chemical reaction, thermal slip, and generation parameters.

Materials system for intermediate temperature solid oxide fuel cells based on doped lanthanum-gallate electrolyte

Science.gov (United States)

Gong, Wenquan

2005-07-01

The objective of this work was to identify a materials system for intermediate temperature solid oxide fuel cells (IT-SOFCs). Towards this goal, alternating current complex impedance spectroscopy was employed as a tool to study electrode polarization effects in symmetrical cells employing strontium and magnesium doped lanthanum gallate (LSGM) electrolyte. Several cathode materials were investigated including strontium doped lanthanum manganite (LSM), Strontium and iron doped lanthanum cobaltate (LSCF), LSM-LSGM, and LSCF-LSGM composites. Investigated Anode materials included nickel-gadolinium or lanthanum doped cerium oxide (Ni-GDC, or Ni-LDC) composites. The ohmic and the polarization resistances of the symmetrical cells were obtained as a function of temperature, time, thickness, and the composition of the electrodes. Based on these studies, the single phase LSM electrode had the highest polarization resistance among the cathode materials. The mixed-conducting LSCF electrode had polarization resistance orders of magnitude lower than that of the LSM-LSGM composite electrodes. Although incorporating LSGM in the LSCF electrode did not reduce the cell polarization resistance significantly, it could reduce the thermal expansion coefficient mismatch between the LSCF electrodes and LSGM electrolyte. Moreover, the polarization resistance of the LSCF electrode decreased asymptotically as the electrode thickness was increased thus suggesting that the electrode thickness needed not be thicker than this asymptotic limit. On the anode side of the IT-SOFC, Ni reacted with LSGM electrolyte, and lanthanum diffusion occurred from the LSGM electrolyte to the GDC barrier layer, which was between the LSGM electrolyte and the Ni-composite anode. However, LDC served as an effective barrier layer. Ni-LDC (70 v% Ni) anode had the largest polarization resistance, while all other anode materials, i.e. Ni-LDC (50 v% Ni), Ni-GDC (70 v% NO, and Ni-GDC (50 v% Ni), had similar polarization

Distinct localization of FMRFamide- and bovine pancreatic polypeptide-like material in the brain, retrocerebral complex and suboesophageal ganglion of the cockroach Periplaneta americana L

DEFF Research Database (Denmark)

Verhaert, P; Grimmelikhuijzen, C J; De Loof, A

1985-01-01

One bovine pancreatic polypeptide (BPP) antiserum and two FMRFamide antisera were applied in the peroxidase-antiperoxidase (PAP) immunohistochemical technique on a complete series of sections of brains, suboesophageal ganglia (SOG), corpora cardiaca (CC) and corpora allata of Periplaneta americana...... L. Double immunohistochemical staining demonstrated that the same perikarya and processes were stained by both the BPP and FMRFamide antisera. This was caused by cross-reaction of the BPP and FMRFamide antisera with common antigenic determinants as was shown by a number of solid-phase absorptions....... Application of a third FMRFamide antiserum, which was especially selected for its inability to react with bovine and avian pancreatic polypeptide, showed that more than half of the structures that were stained with the 'unspecific' BPP and FMRFamide antisera, contained material which was genuinely FMRFamide...

Experimental patch testing with chromium-coated materials.

Science.gov (United States)

Bregnbak, David; Thyssen, Jacob P; Jellesen, Morten S; Zachariae, Claus; Johansen, Jeanne D

2017-06-01

Chromium coatings on metal alloys can be decorative, and prevent corrosion and metal ion release. We recently showed that handling of a chromium-containing disc resulted in chromium deposition on the skin. To examine patch test reactivity to chromium-coated discs. We included 15 patients: 10 chromium-allergic patients, and 5 patients without chromium allergy. All were patch tested with potassium dichromate, cobalt chloride, nickel sulfate, and nine different metallic discs. The chromium-allergic patients were also patch tested with serial dilutions of potassium dichromate. Positive/weaker reactions were observed to disc B (1 of 10), disc C (1 of 10), and disc D, disc E, and disc I (4 of 10 each). As no controls reacted to any of the discs, the weak reactions indicate allergic reactions. Positive patch test reactions to 1770 ppm chromium(VI) in the serial dilutions of potassium dichromate were observed in 7 of 10 patients. When the case group was narrowed down to include only the patients with a current positive patch test reaction to potassium dichromate, elicitation of dermatitis by both chromium(III) and chromium(VI) discs was observed in 4 of 7 of patients. Many of the patients reacted to both chromium(III) and chromium(VI) surfaces. Our results indicate that both chromium(VI) and chromium(III) pose a risk to chromium-allergic patients. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Biogenic Hydroxyapatite: A New Material for the Preservation and Restoration of the Built Environment.

Science.gov (United States)

Turner, Ronald J; Renshaw, Joanna C; Hamilton, Andrea

2017-09-20

Ordinary Portland cement (OPC) is by weight the world's most produced man-made material and is used in a variety of applications in environments ranging from buildings, to nuclear wasteforms, and within the human body. In this paper, we present for the first time the direct deposition of biogenic hydroxyapatite onto the surface of OPC in a synergistic process which uses the composition of the cement substrate. This hydroxyapatite is very similar to that found in nature, having a similar crystallite size, iron and carbonate substitution, and a semi-crystalline structure. Hydroxyapatites with such a structure are known to be mechanically stronger and more biocompatible than synthetic or biomimetic hydroxyapatites. The formation of this biogenic hydroxyapatite coating therefore has significance in a range of contexts. In medicine, hydroxyapatite coatings are linked to improved biocompatibility of ceramic implant materials. In the built environment, hydroxyapatite coatings have been proposed for the consolidation and protection of sculptural materials such as marble and limestone, with biogenic hydroxyapatites having reduced solubility compared to synthetic apatites. Hydroxyapatites have also been established as effective for the adsorption and remediation of environmental contaminants such as radionuclides and heavy metals. We identify that in addition to providing a biofilm scaffold for nucleation, the metabolic activity of Pseudomonas fluorescens increases the pH of the growth medium to a suitable level for hydroxyapatite formation. The generated ammonia reacts with phosphate in the growth medium, producing ammonium phosphates which are a precursor to the formation of hydroxyapatite under conditions of ambient temperature and pressure. Subsequently, this biogenic deposition process takes place in a simple reaction system under mild chemical conditions and is cheap and easy to apply to fragile biological or architectural surfaces.

Reaction of plasmic degradation products of fibrinogen in the radioimmunoassay of human fibrinopeptide A

International Nuclear Information System (INIS)

Budzynski, A.Z.; Marder, V.J.; Sherry, S.

1975-01-01

A radioimmunoassay (RIA) technique has been devised for the measurement of human fibrinopeptide A (FPA). The system utilizes rabbit antiserum to native human FPA and a synthetic fibrinopeptide, with tyrosine substituted for phenylanine in amino acid position 8. The test detects native human FPA at a concentration of 0.1 ng/ml, but does not cross react with human fibrinopeptide B or with fibrinopeptides A from canine, porcine, or bovine fibrinogen. Fibrinogen and chemical or plasmic degradation products with 2 moles of FPA per mole react fully in this test system. This includes the large-molecular-weight intermediate fragments X and Y and the NH 2 -terminal disulfide knot, and indicates that this antibody recognizes and reacts with FPA in the presence of the contiguous peptide structures presents in fibrinogen. Fragment E, which is derived from the NH 2 -terminal portion of fibrinogen, loses most of its FPA content after its liberation from its precursor derivative and reacts to a lesser extent in the RIA than do fragments X and Y. This correlates with the recovery of FPA-positive material from ultrafiltrates of extensive but not partial plasmic digests of fibrinogen. Although FPA immunoreactivity liberated from fibrinogen does not necessarily reflect thrombin activity and/or fibrin formation, only extensive plasmic degradation yields peptide material which reacts in this RIA system. This should not be a serious limitation to the application of the RIA in the detection of venous thrombosis. (U.S.)

Material efficiency: providing material services with less material production.

Science.gov (United States)

Allwood, Julian M; Ashby, Michael F; Gutowski, Timothy G; Worrell, Ernst

2013-03-13

Material efficiency, as discussed in this Meeting Issue, entails the pursuit of the technical strategies, business models, consumer preferences and policy instruments that would lead to a substantial reduction in the production of high-volume energy-intensive materials required to deliver human well-being. This paper, which introduces a Discussion Meeting Issue on the topic of material efficiency, aims to give an overview of current thinking on the topic, spanning environmental, engineering, economics, sociology and policy issues. The motivations for material efficiency include reducing energy demand, reducing the emissions and other environmental impacts of industry, and increasing national resource security. There are many technical strategies that might bring it about, and these could mainly be implemented today if preferred by customers or producers. However, current economic structures favour the substitution of material for labour, and consumer preferences for material consumption appear to continue even beyond the point at which increased consumption provides any increase in well-being. Therefore, policy will be required to stimulate material efficiency. A theoretically ideal policy measure, such as a carbon price, would internalize the externality of emissions associated with material production, and thus motivate change directly. However, implementation of such a measure has proved elusive, and instead the adjustment of existing government purchasing policies or existing regulations-- for instance to do with building design, planning or vehicle standards--is likely to have a more immediate effect.

Recycling steel-manufacturing slag and harbor sediment into construction materials.

Science.gov (United States)

Wei, Yu-Ling; Lin, Chang-Yuan; Cheng, Shao-Hsiang; Wang, H Paul

2014-01-30

Mixtures consisting of harbor sediment and slag waste from steel industry containing toxic components are fired to produce non-hazardous construction materials. The fired pellets become lighter as firing temperature increases. At a sintering temperature of ≦1050°C, the fired pellets are in a form of brick-like product, while at 1100°C, they become lightweight aggregates. Calcium silicate, kyanite, and cristobalite are newly formed in the pellets after firing, demonstrating that calcium oxide acts as a flux component and chemically reacted with Si- and/or Al-containing components to promote sintering. Dioxin/furan content present in the pure slag is 0.003ng I-TEQg(-1) and, for the fired pellet consisting of slag and sediment, the content appears to be destructed and diminishes to 0.0003ng I-TEQg(-1) after 950°C-firing; while it is 0.002ng I-TEQg(-1) after firing at 1100°C, suggesting that dioxins/furans in the 950°C-fired pellets have a greater chance to escape to atmosphere due to a slower sintering reaction and/or that construction of dioxins/furans from molten chloride salts co-exists with their destruction. Multiple toxicity characteristic leaching procedure extracts Cu, Cr, Zn, Se, Cd, Pb, Ba, As, and Hg from all fired products at negligible levels. Copyright © 2013 Elsevier B.V. All rights reserved.

Upgrading of petroleum oil feedstocks using alkali metals and hydrocarbons

Science.gov (United States)

Gordon, John Howard

2014-09-09

A method of upgrading an oil feedstock by removing heteroatoms and/or one or more heavy metals from the oil feedstock composition. This method reacts the oil feedstock with an alkali metal and an upgradant hydrocarbon. The alkali metal reacts with a portion of the heteroatoms and/or one or more heavy metals to form an inorganic phase separable from the organic oil feedstock material. The upgradant hydrocarbon bonds to the oil feedstock material and increases the number of carbon atoms in the product. This increase in the number of carbon atoms of the product increases the energy value of the resulting oil feedstock.

Synthesis and characterization of cathode, anode and electrolyte materials for rechargeable lithium batteries

Science.gov (United States)

Yang, Shoufeng

Two new classes of cathode materials were studied: iron phosphate/sulfate materials and layered manganese oxides, both of which are low cost and had shown some potential. The first class of materials have poor conductivity and cyclability. I studied a number of methods for increasing the conductivity, and determined that grinding the material with carbon black was as effective as special in-situ coatings. The optimum carbon loading was determined to be between 6 and 15 wt%. Too much carbon reduces the volumetric energy density, whereas too little significantly increased cell polarization (reduced the rate of reaction). The kinetic and thermodynamic stability of LiFePO 4 was also studied and it was determined that over discharge protection will be needed as irreversible Li3PO4 can be formed at low potentials. A novel hydrothermal synthesis method was developed, but the significant level of Fe on the Li site reduces the reaction rate too much. In the case of the layered manganese oxide, cation substitution with Co and Ni is found to be effective in avoiding Jahn-Teller effects and improving electrochemistry. A wide range of tin compounds have been suggested as lithium storage media for advanced anode materials, as tin can store over 4 Li per Sn atom. Lithium hexafluorophosphate, LiPF6, is presently the salt of choice for LiCoO2 batteries, but it is expensive and dissolves some manganese compounds. The lithium bis(oxolato)borate (BOB) salt was recently reported, and I made a study of its use in cells with the LiFePO4 cathode and the tin anode. During its synthesis, it became clear that LiBOB is very reactive with many solvents, and these complexes were characterized to better understand this new material. In LiBOB the lithium is five coordinated, an unstable configuration for the lithium ion so that water and many other solvents rapidly react to make a six coordination. Only in the case of ethylene carbonate was the lithium found to be four coordinated. The Li

MALDI-TOF and 13C NMR Analysis of Tannin–Furanic–Polyurethane Foams Adapted for Industrial Continuous Lines Application

Directory of Open Access Journals (Sweden)

Maria Cecilia Basso

2014-12-01

Full Text Available Mixed phenolic-polyurethane-type rigid foams were developed using tannin-furfuryl alcohol natural materials co-reacted with polymeric isocyanate in the proportions imposed by the limitations inherent to continuous industrial plants for polyurethane foams. A variety of different copolymerization oligomers formed. Urethanes appeared to have been formed with two flavonoid tannin sites, mainly at the flavonoid hydroxyl group at C3, but also, although less, on the phenolic hydroxyl groups of the flavonoid oligomers. Urethanes are also formed with (i glyoxal in the formulation, be it pre-reacted or not with the tannin; (ii with phenolsulfonic acid and (iii with furfural. This latter one, however, greatly favors reaction with the A-ring of the flavonoids through a methylene bridge rather than reaction with the isocyanate groups to form urethanes. All of the materials appeared to have co-reacted in a manner to form urethane and methylene bridges between all of the main components used. Thus, the tannin, the furfuryl alcohol, the isocyanate, the glyoxal and even the phenol sulfonic acid hardener formed a number of mixed species linked by the two bridge types. Several mixed species comprised of 2, 3 and even 4 co-reacted different components have been observed.

Commentary: The Materials Project: A materials genome approach to accelerating materials innovation

Directory of Open Access Journals (Sweden)

Anubhav Jain

2013-07-01

Full Text Available Accelerating the discovery of advanced materials is essential for human welfare and sustainable, clean energy. In this paper, we introduce the Materials Project (www.materialsproject.org, a core program of the Materials Genome Initiative that uses high-throughput computing to uncover the properties of all known inorganic materials. This open dataset can be accessed through multiple channels for both interactive exploration and data mining. The Materials Project also seeks to create open-source platforms for developing robust, sophisticated materials analyses. Future efforts will enable users to perform ‘‘rapid-prototyping’’ of new materials in silico, and provide researchers with new avenues for cost-effective, data-driven materials design.

Nanostructured materials with plasmonic nanobiosensors for early cancer detection: A past and future prospect.

Science.gov (United States)

Sugumaran, Sathish; Jamlos, Mohd Faizal; Ahmad, Mohd Noor; Bellan, Chandar Shekar; Schreurs, Dominique

2018-02-15

Early cancer detection and treatment is an emerging and fascinating field of plasmonic nanobiosensor research. It paves to enrich a life without affecting living cells leading to a possible survival of the patient. This review describes a past and future prospect of an integrated research field on nanostructured metamaterials, microwave transmission, surface plasmonic resonance, nanoantennas, and their manifested versatile properties with nano-biosensors towards early cancer detection to preserve human health. Interestingly, (i) microwave transmission shows more advantages than other electromagnetic radiation in reacting with biological tissues, (ii) nanostructured metamaterial (Au) with special properties like size and shape can stimulate plasmonic effects, (iii) plasmonic based nanobiosensors are to explore the efficacy for early cancer tumour detection or single molecular detection and (iv) nanoantenna wireless communication by using microwave inverse scattering nanomesh (MISN) technique instead of conventional techniques can be adopted to characterize the microwave scattered signals from the biomarkers. It reveals that the nanostructured material with plasmonic nanobiosensor paves a fascinating platform towards early detection of cancer tumour and is anticipated to be exploited as a magnificent field in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

Computational Materials Science | Materials Science | NREL

Science.gov (United States)

Computational Materials Science Computational Materials Science An image of interconnecting, sphere science capabilities span many research fields and interests. Electronic, Optical, and Transport Properties of Photovoltaic Materials Material properties and defect physics of Si, CdTe, III-V, CIGS, CZTS

First report on the patient database for the identification of the genetic pathways involved in patients over-reacting to radiotherapy: GENEPI-II

International Nuclear Information System (INIS)

De Ruysscher, Dirk; Severin, Diane; Barnes, Elizabeth; Baumann, Michael; Bristow, Rob; Gregoire, Vincent; Hoelscher, Tobias; Veninga, Theo; Polanski, Andrzej; Veen, Evert-Ben van; Verfaillie, Christine; Heeren, Germaine; Damaraju, Sambasivarao; Just, Uwe; Haustermans, Karin

2010-01-01

Background: Identifying the most radiosensitive patient group would have huge clinical implications. Methods: A tissue bank containing skin fibroblasts, whole blood, lymphocytes, plasma and lymphoblastoid cell lines from clinically radiation hypersensitive patients was established from patients in Europe and Canada. Over-reacting individuals had CTCAE3.0 severe acute side effects grade 2 or more occurring at very low radiation doses where these side effects are unexpected or grade 3-4 lasting more than 4 weeks after the end of radiotherapy and/or requiring surgical intervention at any time or severe late side effects grade 3-4. Results: Eleven patients have been identified with a mean age of 61.6 ± 8.5 years (range 49-74). Two patients were male, 9 female. One patient had non-small cell lung cancer, 6 breast cancer, 2 head and neck cancer, one lymphoma and one meningioma. The mean follow-up time after radiotherapy was 1658 ± 1048 days (range 84-3752). Conclusions: The establishment of an international tissue bank of the rare group of patients with extreme hypersensitivity to radiotherapy was proven to be feasible and should enable in-depth molecular studies.

New Class of Hybrid Materials for Detection, Capture, and "On-Demand" Release of Carbon Monoxide.

Science.gov (United States)

Pitto-Barry, Anaïs; Lupan, Alexandru; Ellingford, Christopher; Attia, Amr A A; Barry, Nicolas P E

2018-04-25

Carbon monoxide (CO) is both a substance hazardous to health and a side product of a number of industrial processes, such as methanol steam reforming and large-scale oxidation reactions. The separation of CO from nitrogen (N 2 ) in industrial processes is considered to be difficult because of the similarities of their electronic structures, sizes, and physicochemical properties (e.g., boiling points). Carbon monoxide is also a major poison in fuel cells because of its adsorption onto the active sites of the catalysts. It is therefore of the utmost economic importance to discover new materials that enable effective CO capture and release under mild conditions. However, methods to specifically absorb and easily release CO in the presence of contaminants, such as water, nitrogen, carbon dioxide, and oxygen, at ambient temperature are not available. Here, we report the simple and versatile fabrication of a new class of hybrid materials that allows capture and release of carbon monoxide under mild conditions. We found that carborane-containing metal complexes encapsulated in networks made of poly(dimethylsiloxane) react with CO, even when immersed in water, leading to dramatic color and infrared signature changes. Furthermore, we found that the CO can be easily released from the materials by simply dipping the networks into an organic solvent for less than 1 min, at ambient temperature and pressure, which not only offers a straightforward recycling method, but also a new method for the "on-demand" release of carbon monoxide. We illustrated the utilization of the on-demand release of CO from the networks by carrying out a carbonylation reaction on an electron-deficient metal complex that led to the formation of the CO-adduct, with concomitant recycling of the gel. We anticipate that our sponge-like materials and scalable methodology will open up new avenues for the storage, transport, and controlled release of CO, the silent killer and a major industrial poison.

Materials Discovery | Materials Science | NREL

Science.gov (United States)

Discovery Materials Discovery Images of red and yellow particles NREL's research in materials characterization of sample by incoming beam and measuring outgoing particles, with data being stored and analyzed Staff Scientist Dr. Zakutayev specializes in design of novel semiconductor materials for energy

Damage development, phase changes, transport properties, and freeze-thaw performance of cementitious materials exposed to chloride based salts

Science.gov (United States)

Farnam, Yaghoob

Recently, there has been a dramatic increase in premature deterioration in concrete pavements and flat works that are exposed to chloride based salts. Chloride based salts can cause damage and deterioration in concrete due to the combination of factors which include: increased saturation, ice formation, salt crystallization, osmotic pressure, corrosion in steel reinforcement, and/or deleterious chemical reactions. This thesis discusses how chloride based salts interact with cementitious materials to (1) develop damage in concrete, (2) create new chemical phases in concrete, (3) alter transport properties of concrete, and (4) change the concrete freeze-thaw performance. A longitudinal guarded comparative calorimeter (LGCC) was developed to simultaneously measure heat flow, damage development, and phase changes in mortar samples exposed to sodium chloride (NaCl), calcium chloride (CaCl 2), and magnesium chloride (MgCl2) under thermal cycling. Acoustic emission and electrical resistivity measurements were used in conjunction with the LGCC to assess damage development and electrical response of mortar samples during cooling and heating. A low-temperature differential scanning calorimetry (LT-DSC) was used to evaluate the chemical interaction that occurs between the constituents of cementitious materials (i.e., pore solution, calcium hydroxide, and hydrated cement paste) and salts. Salts were observed to alter the classical phase diagram for a salt-water system which has been conventionally used to interpret the freeze-thaw behavior in concrete. An additional chemical phase change was observed for a concrete-salt-water system resulting in severe damage in cementitious materials. In a cementitious system exposed to NaCl, the chemical phase change occurs at a temperature range between -6 °C and 8 °C due to the presence of calcium sulfoaluminate phases in concrete. As a result, concrete exposed to NaCl can experience additional freeze-thaw cycles due to the chemical

Materials 2014: a great success for materials sector

International Nuclear Information System (INIS)

Isnard, Olivier; Crepin, Jerome

2014-01-01

In this work are presented the summaries of the 19 symposiums presented at the conference: 'Materials 2014' and whose topics were: eco-materials, materials for energy storage and conversion, strategic materials, rare elements and recycling, surfaces functionalization and physico-chemical characterization, interfaces and coatings, corrosion, aging, durability, damage mechanical behaviours, disordered materials, glasses and their functionalization, materials and health, functional materials, porous, granular and with a high surface area materials, nano-materials, nano-structured systems, assembling processes, carbonaceous materials, great instruments and studies of materials, materials in severe conditions, powder forming processes, metallic materials and structures lightening. (O.M.)

Non-gaseous radiolysis products of procaine benzylpenicillin and Na salt 3-ortho-chloro-5-methyl-4-isoxasolyl penicillin

International Nuclear Information System (INIS)

Dziegielewski, J.; Jezowska-Trzebiatowska, B.

1974-01-01

Radiolysis products of procaine benzylpenicillin and Na salt 3-ortho-chlorophenyl-5-methyl-4-isoxasolyl penicillin were isolated and spectroscopic studies were made over the NMR, IR, UV and mass spectrometric ranges. On the basis of the results obtained, the bond breakage sites resulting from irradiation were determined and the modes of radiolysis decomposition were suggested. Irradiation of penicillins has been found to result in decomposition of the β-lactam and thiazolidine rings. Besides, decarboxylation of penicillins and bond cleavages within the amide group were observed as well as dehydrogenation and abstraction of simple hydrocarbons. The role of procaine and crystallization water in the radiolysis of penicillins was determined. (author)

Brain development in the yellow fever mosquito Aedes aegypti: a comparative immunocytochemical analysis using cross-reacting antibodies from Drosophila melanogaster.

Science.gov (United States)

Mysore, Keshava; Flister, Susanne; Müller, Pie; Rodrigues, Veronica; Reichert, Heinrich

2011-12-01

Considerable effort has been directed towards understanding the organization and function of peripheral and central nervous system of disease vector mosquitoes such as Aedes aegypti. To date, all of these investigations have been carried out on adults but none of the studies addressed the development of the nervous system during the larval and pupal stages in mosquitoes. Here, we first screen a set of 30 antibodies, which have been used to study brain development in Drosophila, and identify 13 of them cross-reacting and labeling epitopes in the developing brain of Aedes. We then use the identified antibodies in immunolabeling studies to characterize general neuroanatomical features of the developing brain and compare them with the well-studied model system, Drosophila melanogaster, in larval, pupal, and adult stages. Furthermore, we use immunolabeling to document the development of specific components of the Aedes brain, namely the optic lobes, the subesophageal neuropil, and serotonergic system of the subesophageal neuropil in more detail. Our study reveals prominent differences in the developing brain in the larval stage as compared to the pupal (and adult) stage of Aedes. The results also uncover interesting similarities and marked differences in brain development of Aedes as compared to Drosophila. Taken together, this investigation forms the basis for future cellular and molecular investigations of brain development in this important disease vector. © Springer-Verlag 2011

Catalytic Upgrading of Bio-Oil by Reacting with Olefins and Alcohols over Solid Acids: Reaction Paths via Model Compound Studies

Directory of Open Access Journals (Sweden)

Qingwen Wang

2013-03-01

Full Text Available Catalytic refining of bio-oil by reacting with olefin/alcohol over solid acids can convert bio-oil to oxygen-containing fuels. Reactivities of groups of compounds typically present in bio-oil with 1-octene (or 1-butanol were studied at 120 °C/3 h over Dowex50WX2, Amberlyst15, Amberlyst36, silica sulfuric acid (SSA and Cs2.5H0.5PW12O40 supported on K10 clay (Cs2.5/K10, 30 wt. %. These compounds include phenol, water, acetic acid, acetaldehyde, hydroxyacetone, d-glucose and 2-hydroxymethylfuran. Mechanisms for the overall conversions were proposed. Other olefins (1,7-octadiene, cyclohexene, and 2,4,4-trimethylpentene and alcohols (iso-butanol with different activities were also investigated. All the olefins and alcohols used were effective but produced varying product selectivities. A complex model bio-oil, synthesized by mixing all the above-stated model compounds, was refined under similar conditions to test the catalyst’s activity. SSA shows the highest hydrothermal stability. Cs2.5/K10 lost most of its activity. A global reaction pathway is outlined. Simultaneous and competing esterification, etherfication, acetal formation, hydration, isomerization and other equilibria were involved. Synergistic interactions among reactants and products were determined. Acid-catalyzed olefin hydration removed water and drove the esterification and acetal formation equilibria toward ester and acetal products.

Towards Materials Sustainability through Materials Stewardship

Directory of Open Access Journals (Sweden)

Christopher D. Taylor

2016-10-01

Full Text Available Materials sustainability requires a concerted change in philosophy across the entire materials lifecycle, orienting around the theme of materials stewardship. In this paper, we address the opportunities for improved materials conservation through dematerialization, durability, design for second life, and diversion of waste streams through industrial symbiosis.

Mixing and NOx Emission Calculations of Confined Reacting Jet Flows in Cylindrical and Annular Ducts

Science.gov (United States)

Oechsle, Victor L.; Connor, Christopher H.; Holdeman, James D. (Technical Monitor)

2000-01-01

Rapid mixing of cold lateral jets with hot cross-stream flows in confined configurations is of practical interest in gas turbine combustors as it strongly affects combustor exit temperature quality, and gaseous emissions in for example rich-lean combustion. It is therefore important to further improve our fundamental understanding of the important processes of dilution jet mixing especially when the injected jet mass flow rate exceeds that of the cross-stream. The results reported in this report describe some of the main flow characteristics which develop in the mixing process in a cylindrical duct. A three-dimensional computational fluid dynamics (CFD) code has been used to predict the mixing flow field characteristics and NOx emission in a quench section of a rich-burn/quick-mix/lean-burn (RQL) combustor. Sixty configurations have been analyzed in both circular and annular geometries in a fully reacting environment simulating the operating condition of an actual RQL gas turbine combustion liner. The evaluation matrix was constructed by varying the number of orifices per row and orifice shape. Other parameters such as J (momentum-flux ratio), MR (mass flowrate ratio), DR (density ratio), and mixer sector orifice ACd (effective orifice area) were maintained constant throughout the entire study. The results indicate that the mixing flow field can be correlated with the NOx production if they are referenced with the stoichiometric equivalence ratio value and not the equilibrium value. The mixing flowfields in both circular and annular mixers are different. The penetration of equal jets in both annular and circular geometries is vastly different which significantly affects the performance of the mixing section. In the computational results with the circular mixer, most of the NOx formation occurred behind the orifice starting at the orifice wake region. General trends have been observed in the NOx production as the number of orifices is changed and this appears to be

Epidemic 2014 enterovirus D68 cross-reacts with human rhinovirus on a respiratory molecular diagnostic platform.

Science.gov (United States)

McAllister, Shane C; Schleiss, Mark R; Arbefeville, Sophie; Steiner, Marie E; Hanson, Ryan S; Pollock, Catherine; Ferrieri, Patricia

2015-01-01

Enterovirus D68 (EV-D68) is an emerging virus known to cause sporadic disease and occasional epidemics of severe lower respiratory tract infection. However, the true prevalence of infection with EV-D68 is unknown, due in part to the lack of a rapid and specific nucleic acid amplification test as well as the infrequency with which respiratory samples are analyzed by enterovirus surveillance programs. During the 2014 EV-D68 epidemic in the United States, we noted an increased frequency of "low-positive" results for human rhinovirus (HRV) detected in respiratory tract samples using the GenMark Diagnostics eSensor respiratory viral panel, a multiplex PCR assay able to detect 14 known respiratory viruses but not enteroviruses. We simultaneously noted markedly increased admissions to our Pediatric Intensive Care Unit for severe lower respiratory tract infections in patients both with and without a history of reactive airway disease. Accordingly, we hypothesized that these "low-positive" RVP results were due to EV-D68 rather than rhinovirus infection. Sequencing of the picornavirus 5' untranslated region (5'-UTR) of 49 samples positive for HRV by the GenMark RVP revealed that 33 (67.3%) were in fact EV-D68. Notably, the mean intensity of the HRV RVP result was significantly lower in the sequence-identified EV-D68 samples (20.3 nA) compared to HRV (129.7 nA). Using a cut-off of 40 nA for the differentiation of EV-D68 from HRV resulted in 94% sensitivity and 88% specificity. The robust diagnostic characteristics of our data suggest that the cross-reactivity of EV-D68 and HRV on the GenMark Diagnostics eSensor RVP platform may be an important factor to consider in making accurate molecular diagnosis of EV-D68 at institutions utilizing this system or other molecular respiratory platforms that may also cross-react.

Far-Field Accumulation of Fissile Material From Waste Packages Containing Plutonium Disposition Waste Form

Energy Technology Data Exchange (ETDEWEB)

J.P. Nicot

2000-09-29

The objective of this calculation is to estimate the quantity of fissile material that could accumulate in fractures in the rock beneath plutonium-ceramic (Pu-ceramic) and Mixed-Oxide (MOX) waste packages (WPs) as they degrade in the potential monitored geologic repository at Yucca Mountain. This calculation is to feed another calculation (Ref. 31) computing the probability of criticality in the systems described in Section 6 and then ultimately to a more general report on the impact of plutonium on the performance of the proposed repository (Ref. 32), both developed concurrently to this work. This calculation is done in accordance with the development plan TDP-DDC-MD-000001 (Ref. 9), item 5. The original document described in item 5 has been split into two documents: this calculation and Ref. 4. The scope of the calculation is limited to only very low flow rates because they lead to the most conservative cases for Pu accumulation and more generally are consistent with the way the effluent from the WP (called source term in this calculation) was calculated (Ref. 4). Ref. 4 (''In-Drift Accumulation of Fissile Material from WPs Containing Plutonium Disposition Waste Forms'') details the evolution through time (breach time is initial time) of the chemical composition of the solution inside the WP as degradation of the fuel and other materials proceed. It is the chemical solution used as a source term in this calculation. Ref. 4 takes that same source term and reacts it with the invert; this calculation reacts it with the rock. In addition to reactions with the rock minerals (that release Si and Ca), the basic mechanisms for actinide precipitation are dilution and mixing with resident water as explained in Section 2.1.4. No other potential mechanism such as flow through a reducing zone is investigated in this calculation. No attempt was made to use the effluent water from the bottom of the invert instead of using directly the effluent water from the

Brazing of special metallic materials and material combinations using a special material

International Nuclear Information System (INIS)

Lison, R.

1981-01-01

The special materials include metals of groups IVa, Va and VIa of the periodic tables and their alloys. Their particular properties have won them applications in many highly specialized industries. For these materials to be used, mastery of thermal joining methods appropriate to their characteristics is necessary. High-temperature brazing is one such method for joining special materials. This paper presents variants of this technique suitable for each individual special material. Compatibility tests between various brazing metals and various special materials have been carried out by simulating the temperature/time cycle involved in brazing procedures. Special materials are relatively expensive, and their special properties are not required at every point in a structure: elsewhere they can be replaced by a different special material or by other metals or alloys. This means that joints must be made between two special materials or between a special material and a conventional material. When certain conditions are fulfilled, such joins can be made by high-temperature brazing. This paper also shows the extent to which the geometry of the join determines the choice of process. Example of applications are also given. (orig.)

Testing of Biologically Inhibiting Surface

DEFF Research Database (Denmark)

Bill Madsen, Thomas; Larsen, Erup

2003-01-01

The main purpose of this course is to examine a newly developed biologically inhibiting material with regards to galvanic corrosion and electrochemical properties. More in detail, the concern was how the material would react when exposed to cleaning agents, here under CIP cleaning (Cleaning...

Materials Informatics: Statistical Modeling in Material Science.

Science.gov (United States)

Yosipof, Abraham; Shimanovich, Klimentiy; Senderowitz, Hanoch

2016-12-01

Material informatics is engaged with the application of informatic principles to materials science in order to assist in the discovery and development of new materials. Central to the field is the application of data mining techniques and in particular machine learning approaches, often referred to as Quantitative Structure Activity Relationship (QSAR) modeling, to derive predictive models for a variety of materials-related "activities". Such models can accelerate the development of new materials with favorable properties and provide insight into the factors governing these properties. Here we provide a comparison between medicinal chemistry/drug design and materials-related QSAR modeling and highlight the importance of developing new, materials-specific descriptors. We survey some of the most recent QSAR models developed in materials science with focus on energetic materials and on solar cells. Finally we present new examples of material-informatic analyses of solar cells libraries produced from metal oxides using combinatorial material synthesis. Different analyses lead to interesting physical insights as well as to the design of new cells with potentially improved photovoltaic parameters. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Studies on manufacturing technology of materials for fine chemical and electronic industry use

Energy Technology Data Exchange (ETDEWEB)

Choi, S K; Kim, B G; Chung, H S; Lee, J C [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

1997-12-01

Fine natural crystalline graphite which is used as a source material of a high electrically conductive film and an addition of advanced high functional solid lubricant. For use high electrically conductive film and advanced high functional solid lubricant, add new and advanced high functional properties to fine graphite powder through surface modification with gas and organic materials. Surface modification methods: 1) Searching for suitable surfactant to improve dispersing characteristics in aqueous system. 2) Adsorption with oxygen on graphite surface to improve dispersing characteristics in oil. 3) Mechanochemical process using hybridization system is to shape control and spontaneous re-arrangement of the surface layer and interaction between the particle surface and extraneous molecules. In aqueous system, the optimum conditions for graphite to disperse is with 0.3-0.5% concentrations of surfactant Lomar D PWA-40 at pH range 10-11. In order to improve dispersing characteristics in oil, the optimum conditions to adsorb over 3.5% with oxygen on graphite surface are as follows: - Tip speed {yields} 3.9 m/sec, - Reaction time {yields} at least 30 min. at 120 deg.C - inert gas and pressure {yields} dried air, 1 kgf/cm{sup 2}. The oxygen contents acts critical point for dispersing graphite in oil system so needs to control oxygen contents by use of air pressure in reacting mill. Chemical methods for coating with Stearic acid and Paraffin need above 15 weight % to graphite powders. Mechanochemical process using hybridization system is to shape control and spontaneous re-arrangement of the surface layer and interaction between the particle surface and extraneous molecules. (author). 45 refs., 9 tabs., 23 figs.

Gas storage materials, including hydrogen storage materials

Science.gov (United States)

Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

2013-02-19

A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

Do Surgeons React?: A Retrospective Analysis of Surgeons' Response to Harassment of a Colleague During Simulated Operating Theatre Scenarios.

Science.gov (United States)

Gostlow, Hannah; Vega, Camila Vega; Marlow, Nicholas; Babidge, Wendy; Maddern, Guy

2017-07-24

To assess and report on surgeons' ability to identify and manage incidences of harassment. The Royal Australasian College of Surgeons is committed to driving out discrimination, bullying, harassment, and sexual harassment from surgical training and practice, through changing the culture of the workplace. To eradicate these behaviors, it is first critical to understand how the current workforce responds to these actions. A retrospective analysis of video data of an operating theatre simulation was conducted to identify how surgeons, from a range of experience levels, react to instances of harassment. Thematic analysis was used to categorize types of harassment and participant response characteristics. The frequency of these responses was assessed and reported. The type of participant response depended on the nature of harassment being perpetuated and the seniority of the participant. In the 50 instances of scripted harassment, active responses were enacted 52% of the time, acknowledgment responses 16%, and no response enacted in 30%. One senior surgeon also perpetuated the harassment (2%). Trainees were more likely to respond actively compared with consultants. It is apparent that trainees are more aware of instances of harassment, and were more likely to intervene during the simulated scenario. However, a large proportion of harassment was unchallenged. The hierarchical nature of surgical education and the surgical workforce in general needs to enable a culture in which the responsibility to intervene is allowed and respected. Simulation-based education programs could be developed to train in the recognition and intervention of discrimination, bullying, harassment and sexual harassment.

Enhancement of discharge performance of Li/CF x cell by thermal treatment of CF x cathode material

Science.gov (United States)

Zhang, Sheng S.; Foster, Donald; Read, Jeffrey

In this work we demonstrate that the thermal treatment of CF x cathode material just below the decomposition temperature can enhance discharge performance of Li/CF x cells. The performance enhancement becomes more effective when heating a mixture of CF x and citric acid (CA) since CA serves as an extra carbon source. Discharge experiments show that the thermal treatment not only reduces initial voltage delay, but also raises discharge voltage. Whereas the measurement of powder impedance indicates the thermal treatment does not increase electronic conductivity of CF x material. Based on these facts, we propose that the thermal treatment results in a limited decomposition of CF x, which yields a subfluorinated carbon (CF x- δ), instead of a highly conductive carbon. In the case of CF x/AC mixture, the AC provides extra carbon that reacts with F 2 and fluorocarbon radicals generated by the thermal decomposition of CF x to form subfluorinated carbon. The process of thermal treatment is studied by thermogravimetric analysis and X-ray diffraction, and the effect of treatment conditions such as heating temperature, heating time and CF x/CA ratio on the discharge performance of CF x cathode is discussed. As an example, a Li/CF x cell using CF x treated with CA at 500 °C under nitrogen for 2 h achieved theretical specific capacity when being discharged at C/5. Impedance analysis indicates that the enhanced performance is attributed to a significant reduction in the cell reaction resistance.

Materials, critical materials and clean-energy technologies

Science.gov (United States)

Eggert, R.

2017-07-01

Modern engineered materials, components and systems depend on raw materials whose properties provide essential functionality to these technologies. Some of these raw materials are subject to supply-chain risks, and such materials are known as critical materials. This paper reviews corporate, national and world perspectives on material criticality. It then narrows its focus to studies that assess "what is critical" to clean-energy technologies. The focus on supply-chain risks is not meant to be alarmist but rather to encourage attention to monitoring these risks and pursuing technological innovation to mitigate the risks.

Physical response of backfill materials to mineralogical changes in a basalt environment

International Nuclear Information System (INIS)

Couture, R.A.; Seitz, M.G.

1983-01-01

Backfill materials surrounding waste canisters in a high-level nuclear waste repository are capable of ensuring very slow flow of groundwater past the canisters, and thereby increase the safety of the repository. However, in the design of a repository it will be necessary to allow for possible changes in the backfill. In this experimental program, changes in permeability, swelling behavior, and plastic behavior of the backfill at the temperatures, pressures, and radiation levels expected in a repository are investigated. The emphasis is on investigation of relevant phenomena and evaluation of experimental procedures for use in licensing procedures. The permeability of a slightly compacted sand-clay mixture containing 25% bentonite, with a dry bulk density of 1.59 g/cm 3 , was determined to be 0.9 x 10 -18 m 2 in liquid water at 25 and 200 0 C, respectively. This is sufficiently low to demonstrate the potential effectiveness of proposed materials. In practice, fractures in the host rock may form short circuits around the backfill, so an even lower flow rate is probable. However, alteration by any of several mechanisms is expected to change the properties of the backfill. Crushed basalt plus bentonite is a leading candidate backfill for a basalt repository. Experiments show that basalt reacts with groundwater vapor or with liquid groundwater producing smectites, zeolites, silica, and other products that may be either beneficial or detrimental to the long-term performance of the backfill. Concentration of groundwater salts in the backfill by evaporation would cause immediate, but possibly reversible, reduction of the swelling abaility of bentonite. Moreover, under some circumstances, gamma radiolysis of moist air in the backfill could produce up to 0.5 mole of nitric acid or ammonia per liter of pore space. 27 references, 7 figures, 4 tables

Interaction of a weak and a strong shock in reacting high enthalpy flow; Wechselwirkung einer starken und einer schwachen Stosswelle in reagierender Hochenthalpiestroemung

Energy Technology Data Exchange (ETDEWEB)

Schnieder, M.

1998-11-01

In the free piston driven shock tunnel HEG the interaction of shock waves in front of a blunt body is studied in reacting high enthalpy flow. The influence of high temperature effects is of interest. The so called type IV interaction produces a free jet that impinges onto the body and creates high pressure and heat loads on the body surface. A cylinder wedge model is used. At the cylinder surface pressure and heat flux are measured. Holographic interferometry and schlieren optic are applied to visualize the flow. The measured loads show unsteady behaviour. At higher Reynolds numbers the upper bow shock shows a strong disturbance. It is assumed that this disturbance is caused by an unstable shear layer if the convective Mach number (i.e. the Mach number of the flow relative to a frame of reference moving with the shear layer structures) is larger than one. A study of the influence of dissociation on the convective Mach number shows, that the convective Mach number increases. Numerical calculations and an analytical model, which is based on the ideal dissociating gas model and the Fay Riddell solution to stagnation point flows are discussed in comparison with the experiments. (orig.)

Further important sensitizers in patients sensitive to fragrances

DEFF Research Database (Denmark)

Frosch, Peter J; Johansen, J D; Menné, T

2002-01-01

(series I). Each patient was classified regarding a history of adverse reactions to fragrances: certain, probable, questionable, none. Reactions to FM occurred in 11.3% of the subjects. The 6 substances with the highest reactivity following FM were Lyral (2.7%), citral (1.1%), farnesol P (0.......5%), citronellol (0.4%), hexyl cinnamic aldehyde (0.3%), and coumarin (0.3%). 41 (2.2%) of the patients reacted only to materials of series I and not to FM. 6.6% of 1855 patients gave a history of adverse reactions to fragrances which was classified as certain. This group reacted to FM only in 41.1%, to series I...... and FM in 12.0% and to series I only in 7.2%. 74.3% of the 39 patients reacting to both FM and 1 of the materials of series I had any type of positive fragrance history, which was significantly higher in comparison to those with isolated reactions to series I (53.6% of 41), p = 0.04. The study identified...

Material Science

Energy Technology Data Exchange (ETDEWEB)

Won, Dong Yeon; Kim, Heung

1987-08-15

This book introduces material science, which includes key of a high-tech industry, new materials of dream like new metal material and semiconductor, classification of materials, microstructure of materials and characteristic. It mentions magic new materials such as shape memory alloy, fine ceramics, engineering fine ceramics, electronic ceramics, engineering plastic, glass, silicone conductor, optical fiber mixed materials and integrated circuit, challenge for new material and development of new materials.

Material Science

International Nuclear Information System (INIS)

Won, Dong Yeon; Kim, Heung

1987-08-01

This book introduces material science, which includes key of a high-tech industry, new materials of dream like new metal material and semiconductor, classification of materials, microstructure of materials and characteristic. It mentions magic new materials such as shape memory alloy, fine ceramics, engineering fine ceramics, electronic ceramics, engineering plastic, glass, silicone conductor, optical fiber mixed materials and integrated circuit, challenge for new material and development of new materials.

Materials, critical materials and clean-energy technologies

Directory of Open Access Journals (Sweden)

Eggert R.

2017-01-01

Full Text Available Modern engineered materials, components and systems depend on raw materials whose properties provide essential functionality to these technologies. Some of these raw materials are subject to supply-chain risks, and such materials are known as critical materials. This paper reviews corporate, national and world perspectives on material criticality. It then narrows its focus to studies that assess “what is critical” to clean-energy technologies. The focus on supply-chain risks is not meant to be alarmist but rather to encourage attention to monitoring these risks and pursuing technological innovation to mitigate the risks.

Reacting to Neighborhood Cues?

DEFF Research Database (Denmark)

Danckert, Bolette; Dinesen, Peter Thisted; Sønderskov, Kim Mannemar

2017-01-01

is founded on politically sophisticated individuals having a greater comprehension of news and other mass-mediated sources, which makes them less likely to rely on neighborhood cues as sources of information relevant for political attitudes. Based on a unique panel data set with fine-grained information...