Study of anyon condensation and topological phase transitions from a Z4 topological phase using the projected entangled pair states approach

NASA Astrophysics Data System (ADS)

Iqbal, Mohsin; Duivenvoorden, Kasper; Schuch, Norbert

2018-05-01

We use projected entangled pair states (PEPS) to study topological quantum phase transitions. The local description of topological order in the PEPS formalism allows us to set up order parameters which measure condensation and deconfinement of anyons and serve as substitutes for conventional order parameters. We apply these order parameters, together with anyon-anyon correlation functions and some further probes, to characterize topological phases and phase transitions within a family of models based on a Z4 symmetry, which contains Z4 quantum double, toric code, double semion, and trivial phases. We find a diverse phase diagram which exhibits a variety of different phase transitions of both first and second order which we comprehensively characterize, including direct transitions between the toric code and the double semion phase.

Advances in modelling of condensation phenomena

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, W.S.; Zaltsgendler, E.; Hanna, B.

1997-07-01

The physical parameters in the modelling of condensation phenomena in the CANDU reactor system codes are discussed. The experimental programs used for thermal-hydraulic code validation in the Canadian nuclear industry are briefly described. The modelling of vapour generation and in particular condensation plays a key role in modelling of postulated reactor transients. The condensation models adopted in the current state-of-the-art two-fluid CANDU reactor thermal-hydraulic system codes (CATHENA and TUF) are described. As examples of the modelling challenges faced, the simulation of a cold water injection experiment by CATHENA and the simulation of a condensation induced water hammer experiment by TUFmore » are described.« less

Mitigating PTSD: Emotionally Intelligent Leaders

DTIC Science & Technology

2010-05-28

lower ranking, less educated members, those who had experienced childhood adversity, and who were single, separated or divorced .10 The number of...Pr og ra m R es ea rc h Pr oj ec t MITIGATING PTSD: EMOTIONALLY INTELLIGENT LEADERS BY COLONEL RAMONA M. FIOREY United States Army...COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Mitigating PTSD: Emotionally Intelligent Leaders 5b. GRANT NUMBER

Incorporation of Condensation Heat Transfer in a Flow Network Code

NASA Technical Reports Server (NTRS)

Anthony, Miranda; Majumdar, Alok; McConnaughey, Paul K. (Technical Monitor)

2001-01-01

In this paper we have investigated the condensation of water vapor in a short tube. A numerical model of condensation heat transfer was incorporated in a flow network code. The flow network code that we have used in this paper is Generalized Fluid System Simulation Program (GFSSP). GFSSP is a finite volume based flow network code. Four different condensation models were presented in the paper. Soliman's correlation has been found to be the most stable in low flow rates which is of particular interest in this application. Another highlight of this investigation is conjugate or coupled heat transfer between solid or fluid. This work was done in support of NASA's International Space Station program.

Calculations of condensation and chemistry in an aircraft contrail

NASA Technical Reports Server (NTRS)

Miake-Lye, Richard C.; Brown, R. C.; Anderson, M. R.; Kolb, C. E.

1994-01-01

The flow field, chemistry, and condensation nucleation behind a transport airplane are calculated in two regimes using two separate reacting flow codes: first the axisymmetric plume, then the three dimensional vortex wake. The included chemical kinetics equations follow the evolution of the NO(y) and SO(x) chemical families. In the plume regime, the chemistry is coupled with the binary homogeneous formation of sulfate condensation nuclei, where the calculated nucleation rates predict that copious quantities of H2SO4/H2O nuclei are produced in subnanometer sizes. These sulfate aerosols could play a major role in the subsequent condensation of water vapor and the formation of contrails under favorable atmospheric conditions.

Acceptance criteria for welds in ASTM A106 grade B steel pipe and plate

NASA Technical Reports Server (NTRS)

Hudson, C. M.; Wright, D. B., Jr.; Leis, B. N.

1986-01-01

Based on the RECERT Program findings, NASA-Langley funded a fatigue study of code-unacceptable welds. Usage curves were developed which were based on the structural integrity of the welds. The details of this study are presented in NASA CR-178114. The information presented is a condensation and reinterpretation of the information in NASA CR-178114. This condensation and reinterpretation generated usage curves for welds having: (1) indications 0.20 -inch deep by 0.40-inch long, and (2) indications 0.195-inch deep by 8.4-inches long. These curves were developed using the procedures used in formulating the design curves in Section VIII, Division 2 of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.

The Fireball integrated code package

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dobranich, D.; Powers, D.A.; Harper, F.T.

1997-07-01

Many deep-space satellites contain a plutonium heat source. An explosion, during launch, of a rocket carrying such a satellite offers the potential for the release of some of the plutonium. The fireball following such an explosion exposes any released plutonium to a high-temperature chemically-reactive environment. Vaporization, condensation, and agglomeration processes can alter the distribution of plutonium-bearing particles. The Fireball code package simulates the integrated response of the physical and chemical processes occurring in a fireball and the effect these processes have on the plutonium-bearing particle distribution. This integrated treatment of multiple phenomena represents a significant improvement in the state ofmore » the art for fireball simulations. Preliminary simulations of launch-second scenarios indicate: (1) most plutonium vaporization occurs within the first second of the fireball; (2) large non-aerosol-sized particles contribute very little to plutonium vapor production; (3) vaporization and both homogeneous and heterogeneous condensation occur simultaneously; (4) homogeneous condensation transports plutonium down to the smallest-particle sizes; (5) heterogeneous condensation precludes homogeneous condensation if sufficient condensation sites are available; and (6) agglomeration produces larger-sized particles but slows rapidly as the fireball grows.« less

Systematic text condensation: a strategy for qualitative analysis.

PubMed

Malterud, Kirsti

2012-12-01

To present background, principles, and procedures for a strategy for qualitative analysis called systematic text condensation and discuss this approach compared with related strategies. Giorgi's psychological phenomenological analysis is the point of departure and inspiration for systematic text condensation. The basic elements of Giorgi's method and the elaboration of these in systematic text condensation are presented, followed by a detailed description of procedures for analysis according to systematic text condensation. Finally, similarities and differences compared with other frequently applied methods for qualitative analysis are identified, as the foundation of a discussion of strengths and limitations of systematic text condensation. Systematic text condensation is a descriptive and explorative method for thematic cross-case analysis of different types of qualitative data, such as interview studies, observational studies, and analysis of written texts. The method represents a pragmatic approach, although inspired by phenomenological ideas, and various theoretical frameworks can be applied. The procedure consists of the following steps: 1) total impression - from chaos to themes; 2) identifying and sorting meaning units - from themes to codes; 3) condensation - from code to meaning; 4) synthesizing - from condensation to descriptions and concepts. Similarities and differences comparing systematic text condensation with other frequently applied qualitative methods regarding thematic analysis, theoretical methodological framework, analysis procedures, and taxonomy are discussed. Systematic text condensation is a strategy for analysis developed from traditions shared by most of the methods for analysis of qualitative data. The method offers the novice researcher a process of intersubjectivity, reflexivity, and feasibility, while maintaining a responsible level of methodological rigour.

Translation of the Department of Defense Disease and Injury Codes to the Eighth Revision International Classification of Diseases for use by the Military Services.

DTIC Science & Technology

1976-06-01

with, the DDDIC entity. 3. The ICDA-8 contracts groups of diseases or accidents which had been presented in expanded form in the DDDIC. Example: DDDIC...DDDIC. 4. The ICDA-8 expands groups of entities which had been presented in more condensed folin in the DDDIC. Example: DDDIC ICDA-8 Code Ntmuber Code...rapidly find a disease entity and all closely related entities. At the Naval Health Research Center (N11RC) a new code nunber was given to each

Patterns in the sky: Natural visualization of aircraft flow fields

NASA Technical Reports Server (NTRS)

Campbell, James F.; Chambers, Joseph R.

1994-01-01

The objective of the current publication is to present the collection of flight photographs to illustrate the types of flow patterns that were visualized and to present qualitative correlations with computational and wind tunnel results. Initially in section 2, the condensation process is discussed, including a review of relative humidity, vapor pressure, and factors which determine the presence of visible condensate. Next, outputs from computer code calculations are postprocessed by using water-vapor relationships to determine if computed values of relative humidity in the local flow field correlate with the qualitative features of the in-flight condensation patterns. The photographs are then presented in section 3 by flow type and subsequently in section 4 by aircraft type to demonstrate the variety of condensed flow fields that was visualized for a wide range of aircraft and flight maneuvers.

Microphysical Model Studies of Venus Clouds

NASA Astrophysics Data System (ADS)

Meade, P. E.; Bullock, M. A.; Grinspoon, D. H.

2004-11-01

We have adapted a standard cloud microphysics model to construct a self-consistent microphysical model of Venus' cloud layer which reproduces and extends previous studies (e.g. James et al. 1997). Our model is based on the Community Aerosol and Radiation Model Atmosphere (CARMA), which is a widely used computer code for terrestrial cloud microphysics, derived from the work of Toon et al. (1988). The standard code has been adapted to treat H2O and H2SO4 as co-condensing vapor species onto aqueous H2SO4 cloud droplets, as well as the nucleation of condensation nuclei to droplets. Vapor condensation and evaporation follows the method of James et al. (1997). Microphysical processes included in this model include nucleation of condensation nuclei, condensation and evaporation of H2O and H2SO4 vapor, and droplet coagulation. Vertical transport occurs though advection, eddy diffusion, sedimentation for both droplets and condensation nuclei. The cloud model is used to explore the sensitivity of Venus' cloud layer to environmental changes. Observations of the Venus' lower cloud from the Pioneer Venus, Venera, and Galileo spacecraft have suggested that the properties of the lower cloud may be time-variable, and at times may be entirely absent (Carlson et al. 1993, Grinspoon et al. 1993, Esposito et al. 1997). Our model explores the dependence of such behavior on environment factors such as variations in water or SO2 abundance. We have also calculated the optical properties of the model atmosphere using both the conventional optical constants for H2SO4 (Palmer and Williams, 1975), and the new data of Tisdale et al. (1998). This work has been supported by NASA's Exobiology Program. References Carlson, R.W., et al., 1993. Planetary and Space Science, 41, 477-486. Esposito, L.W., et al., 1997. In Venus II, eds. S.W. Bougher et al., pp. 415-458, University of Arizona Press, Tucson. Grinspoon, D.H., et al., 1993. Planetary and Space Science, 41 (July 1993), 515-542. James, E. P., et al., 1997. Icarus, 129, 147-171. Palmer, K.F., and D. Williams, 1975. Applied Optics, 14, 208-219. Tisdale, R.T., et al., 1998. Journal of Geophysical Research, 103, 25,353-25,370. Toon , O. B., et al., 1988. J. Atmos. Sci., 45, 2123-2143.

Direct Numerical Simulation of Turbulent Condensation in Clouds

NASA Technical Reports Server (NTRS)

Shariff, K.; Paoli, R.

2004-01-01

In this brief, we investigate the turbulent condensation of a population of droplets by means of a direct numerical simulation. To that end, a coupled Navier-Stokes/Lagrangian solver is used where each particle is tracked and its growth by water vapor condensation is monitored exactly. The main goals of the study are to find out whether turbulence broadens the droplet size distribution, as observed in in situ measurements. The second issue is to understand if and for how long a correlation between the droplet radius and the local supersaturation exists for the purpose of modeling sub-grid scale microphysics in cloud-resolving codes. This brief is organized as follows. In Section 2 the governing equations are presented, including the droplet condensation model. The implementation of the forcing procedure is described in Section 3. The simulation results are presented in Section 4 together with a sketch of a simple stochastic model for turbulent condensation. Conclusions and the main outcomes of the study are given in Section 5.

78 FR 68019 - Performance Review Board Appointments

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-13

....; Chasteen, G. Taylor; Christian, Lisa A.; Clanton, Michael W.; Coffee, Richard; Cook, Cheryl L.; Davenport....; Paul, Matt; Pfaeffle, Frederick; Pino, Lisa; Repass, Todd; Robinson, Quinton; Romero, Ramona; Ruiz..., Lisa; Wright, Ann; Young, Benjamin; Young, Mike; Zehren, Christopher J. Marketing and Regulatory...

Determinant Computation on the GPU using the Condensation Method

NASA Astrophysics Data System (ADS)

Anisul Haque, Sardar; Moreno Maza, Marc

2012-02-01

We report on a GPU implementation of the condensation method designed by Abdelmalek Salem and Kouachi Said for computing the determinant of a matrix. We consider two types of coefficients: modular integers and floating point numbers. We evaluate the performance of our code by measuring its effective bandwidth and argue that it is numerical stable in the floating point number case. In addition, we compare our code with serial implementation of determinant computation from well-known mathematical packages. Our results suggest that a GPU implementation of the condensation method has a large potential for improving those packages in terms of running time and numerical stability.

Condensation model for the ESBWR passive condensers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Revankar, S. T.; Zhou, W.; Wolf, B.

2012-07-01

In the General Electric's Economic simplified boiling water reactor (GE-ESBWR) the passive containment cooling system (PCCS) plays a major role in containment pressure control in case of an loss of coolant accident. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure following a design basis accident. There are three PCCS condensation modes depending on the containment pressurization due to coolant discharge; complete condensation, cyclic venting and flow through mode. The present work reviews the models and presents model predictive capability along with comparison with existing data frommore » separate effects test. The condensation models in thermal hydraulics code RELAP5 are also assessed to examine its application to various flow modes of condensation. The default model in the code predicts complete condensation well, and basically is Nusselt solution. The UCB model predicts through flow well. None of condensation model in RELAP5 predict complete condensation, cyclic venting, and through flow condensation consistently. New condensation correlations are given that accurately predict all three modes of PCCS condensation. (authors)« less

Remembering the University of Utah.

ERIC Educational Resources Information Center

Haglund, Elizabeth, Ed.

Nineteen essays comprise this personal and historical look at the University of Utah and the relationship between the university, its people, and the community. Essays include: "One Cannot Live Long Enough to Outgrow a University" (Ramona Wilcox Cannon); "Ever in the Freshness of Its Youth" (G. Homer Durham); "The Final…

77 FR 23007 - Endangered and Threatened Wildlife and Plants; Designation of Revised Critical Habitat for Allium...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-17

... Jacinto River between the Ramona Expressway and the mouth of Railroad Canyon for a total of 61 localities... Nichols Road, near the mouth of Walker Canyon (CNDDB 2011b, EO16). A survey in 2005 recorded 10 plants...

Development of a Model and Computer Code to Describe Solar Grade Silicon Production Processes

NASA Technical Reports Server (NTRS)

Srivastava, R.; Gould, R. K.

1979-01-01

Mathematical models and computer codes based on these models, which allow prediction of the product distribution in chemical reactors for converting gaseous silicon compounds to condensed-phase silicon were developed. The following tasks were accomplished: (1) formulation of a model for silicon vapor separation/collection from the developing turbulent flow stream within reactors of the Westinghouse (2) modification of an available general parabolic code to achieve solutions to the governing partial differential equations (boundary layer type) which describe migration of the vapor to the reactor walls, (3) a parametric study using the boundary layer code to optimize the performance characteristics of the Westinghouse reactor, (4) calculations relating to the collection efficiency of the new AeroChem reactor, and (5) final testing of the modified LAPP code for use as a method of predicting Si(1) droplet sizes in these reactors.

"Celebrate Science" Has Formula for Hands-On Learning

ERIC Educational Resources Information Center

Brydolf, Carol

2012-01-01

Cost-effective, easily replicated program is a win-win situation for high schoolers who teach science and for their elementary students. The thank-you letter from Leslie, a grade-schooler in San Diego County's Ramona Unified School District, speaks volumes about the excitement generated by "Celebrate Science"--an innovative,…

Deepak Condenser Model (DeCoM)

NASA Technical Reports Server (NTRS)

Patel, Deepak

2013-01-01

Development of the DeCoM comes from the requirement of analyzing the performance of a condenser. A component of a loop heat pipe (LHP), the condenser, is interfaced with the radiator in order to reject heat. DeCoM simulates the condenser, with certain input parameters. Systems Improved Numerical Differencing Analyzer (SINDA), a thermal analysis software, calculates the adjoining component temperatures, based on the DeCoM parameters and interface temperatures to the radiator. Application of DeCoM is (at the time of this reporting) restricted to small-scale analysis, without the need for in-depth LHP component integrations. To efficiently develop a model to simulate the LHP condenser, DeCoM was developed to meet this purpose with least complexity. DeCoM is a single-condenser, single-pass simulator for analyzing its behavior. The analysis is done based on the interactions between condenser fluid, the wall, and the interface between the wall and the radiator. DeCoM is based on conservation of energy, two-phase equations, and flow equations. For two-phase, the Lockhart- Martinelli correlation has been used in order to calculate the convection value between fluid and wall. Software such as SINDA (for thermal analysis analysis) and Thermal Desktop (for modeling) are required. DeCoM also includes the ability to implement a condenser into a thermal model with the capability of understanding the code process and being edited to user-specific needs. DeCoM requires no license, and is an open-source code. Advantages to DeCoM include time dependency, reliability, and the ability for the user to view the code process and edit to their needs.

Digital Citizenship and Health Promotion Programs: The Power of Knowing.

PubMed

Hicks, Elaine R

2016-11-03

Patterns of Internet access and use among disadvantaged subgroups of Americans reveal that not all disparities are the same, a distinction crucial for appropriate public policies and health promotion program planning. In their book, Digital Citizenship: The Internet, Society, and Participation, authors Karen Mossberger, Caroline Tolbert, and Ramona McNeal deconstructed national opinion surveys and used multivariate methods of data analysis to demonstrate the impact of exclusion from online society economically, socially, and politically among disadvantaged Americans. © 2016 Society for Public Health Education.

Modeling of Non-Homogeneous Containment Atmosphere in the ThAI Experimental Facility Using a CFD Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babic, Miroslav; Kljenak, Ivo; Mavko, Borut

2006-07-01

The CFD code CFX4.4 was used to simulate an experiment in the ThAI facility, which was designed for investigation of thermal-hydraulic processes during a severe accident inside a Light Water Reactor containment. In the considered experiment, air was initially present in the vessel, and helium and steam were injected during different phases of the experiment at various mass flow rates and at different locations. The main purpose of the simulation was to reproduce the non-homogeneous temperature and species concentration distributions in the ThAI experimental facility. A three-dimensional model of the ThAI vessel for the CFX4.4 code was developed. The flowmore » in the simulation domain was modeled as single-phase. Steam condensation on vessel walls was modeled as a sink of mass and energy using a correlation that was originally developed for an integral approach. A simple model of bulk phase change was also introduced. The calculated time-dependent variables together with temperature and concentration distributions at the end of experiment phases are compared to experimental results. (authors)« less

78 FR 46599 - Wild Horse and Burro Advisory Board Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-01

... DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLWO2600000 L10600000 XQ0000] Wild Horse and... Bureau of Land Management (BLM) announces that the Wild Horse and Burro Advisory Board will conduct a... mailed to National Wild Horse and Burro Program, WO-260, Attention: Ramona DeLorme, 1340 Financial...

Back Propagation Artificial Neural Network and Its Application in Fault Detection of Condenser Failure in Thermo Plant

NASA Astrophysics Data System (ADS)

Ismail, Firas B.; Thiruchelvam, Vinesh

2013-06-01

Steam condenser is one of the most important equipment in steam power plants. If the steam condenser trips it may lead to whole unit shutdown, which is economically burdensome. Early condenser trips monitoring is crucial to maintain normal and safe operational conditions. In the present work, artificial intelligent monitoring systems specialized in condenser outages has been proposed and coded within the MATLAB environment. The training and validation of the system has been performed using real operational measurements captured from the control system of selected steam power plant. An integrated plant data preparation scheme for condenser outages with related operational variables has been proposed. Condenser outages under consideration have been detected by developed system before the plant control system"

Accounting for the Effect of Noncondensing Gases on Interphasic Heat and Mass Transfer in the Two-Fluid Model Used in the KORSAR Code

NASA Astrophysics Data System (ADS)

Yudov, Yu. V.

2018-03-01

A model is presented of the interphasic heat and mass transfer in the presence of noncondensable gases for the KORSAR/GP design code. This code was developed by FGUP NITI and the special design bureau OKB Gidropress. It was certified by Rostekhnadzor in 2009 for numerical substantiation of the safety of reactor installations with VVER reactors. The model is based on the assumption that there are three types of interphasic heat and mass transfer of the vapor component: vapor condensation or evaporation on the interphase under any thermodynamic conditions of the phases, pool boiling of the liquid superheated above the saturation temperature at the total pressure, and spontaneous condensation in the volume of gas phase supercooled below the saturation temperature at the vapor partial pressure. Condensation and evaporation on the interphase continuously occur in a two-phase flow and control the time response of the interphase heat and mass transfer. Boiling and spontaneous condensation take place only at the metastable condition of the phases and run at a quite high speed. The procedure used for calculating condensation and evaporation on the interphase accounts for the combined diffusion and thermal resistance of mass transfer in all regimes of the two-phase flow. The proposed approach accounts for, in a natural manner, a decrease in the rate of steam condensation (or generation) in the presence of noncondensing components in the gas phase due to a decrease (or increase) in the interphase temperature relative to the saturation temperature at the vapor partial pressure. The model of the interphase heat transfer also accounts for the processes of dissolution or release of noncondensing components in or from the liquid. The gas concentration at the interphase and on the saturation curve is calculated by the Henry law. The mass transfer coefficient in gas dissolution is based on the heat and mass transfer analogy. Results are presented of the verification of the interphase heat and mass transfer used in the KORSAR/GP code based on the data on film condensation of steam-air flows in vertical pipes. The proposed model was also tested by solving a problem of nitrogen release from a supersaturated water solution.

One Dimensional Analysis Model of a Condensing Spray Chamber Including Rocket Exhaust Using SINDA/FLUINT and CEA

NASA Technical Reports Server (NTRS)

Sakowski, Barbara; Edwards, Daryl; Dickens, Kevin

2014-01-01

Modeling droplet condensation via CFD codes can be very tedious, time consuming, and inaccurate. CFD codes may be tedious and time consuming in terms of using Lagrangian particle tracking approaches or particle sizing bins. Also since many codes ignore conduction through the droplet and or the degradating effect of heat and mass transfer if noncondensible species are present, the solutions may be inaccurate. The modeling of a condensing spray chamber where the significant size of the water droplets and the time and distance these droplets take to fall, can make the effect of droplet conduction a physical factor that needs to be considered in the model. Furthermore the presence of even a relatively small amount of noncondensible has been shown to reduce the amount of condensation [Ref 1]. It is desirable then to create a modeling tool that addresses these issues. The path taken to create such a tool is illustrated. The application of this tool and subsequent results are based on the spray chamber in the Spacecraft Propulsion Research Facility (B2) located at NASA's Plum Brook Station that tested an RL-10 engine. The platform upon which the condensation physics is modeled is SINDAFLUINT. The use of SINDAFLUINT enables the ability to model various aspects of the entire testing facility, including the rocket exhaust duct flow and heat transfer to the exhaust duct wall. The ejector pumping system of the spray chamber is also easily implemented via SINDAFLUINT. The goal is to create a transient one dimensional flow and heat transfer model beginning at the rocket, continuing through the condensing spray chamber, and finally ending with the ejector pumping system. However the model of the condensing spray chamber may be run independently of the rocket and ejector systems detail, with only appropriate mass flow boundary conditions placed at the entrance and exit of the condensing spray chamber model. The model of the condensing spray chamber takes into account droplet conduction as well as the degrading effect of mass and heat transfer due to the presence of noncondensibles. The one dimension model of the condensing spray chamber makes no presupposition on the pressure profile within the chamber, allowing the implemented droplet physics of heat and mass transfer coupled to the SINDAFLUINT solver to determine a transient pressure profile of the condensing spray chamber. Model results compare well to the RL-10 engine pressure test data.

FACES (Friday Afternoon Choices for Enrichment for Our Students).

ERIC Educational Resources Information Center

Myers, Donna

THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: It has been the goal of the staff and parents at Ramona Elementary School to provide more enriching opportunities for our students. We want to stimulate learning and expand our horizons in every area of the curriculum. Parents, community members, and the school staff work together to provide these…

An easily implemented static condensation method for structural sensitivity analysis

NASA Technical Reports Server (NTRS)

Gangadharan, S. N.; Haftka, R. T.; Nikolaidis, E.

1990-01-01

A black-box approach to static condensation for sensitivity analysis is presented with illustrative examples of a cube and a car structure. The sensitivity of the structural response with respect to joint stiffness parameter is calculated using the direct method, forward-difference, and central-difference schemes. The efficiency of the various methods for identifying joint stiffness parameters from measured static deflections of these structures is compared. The results indicate that the use of static condensation can reduce computation times significantly and the black-box approach is only slightly less efficient than the standard implementation of static condensation. The ease of implementation of the black-box approach recommends it for use with general-purpose finite element codes that do not have a built-in facility for static condensation.

An assessment of the CORCON-MOD3 code. Part 1: Thermal-hydraulic calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strizhov, V.; Kanukova, V.; Vinogradova, T.

1996-09-01

This report deals with the subject of CORCON-Mod3 code validation (thermal-hydraulic modeling capability only) based on MCCI (molten core concrete interaction) experiments conducted under different programs in the past decade. Thermal-hydraulic calculations (i.e., concrete ablation, melt temperature, melt energy, concrete temperature, and condensible and non-condensible gas generation) were performed with the code, and compared with the data from 15 experiments, conducted at different scales using both simulant (metallic and oxidic) and prototypic melt materials, using different concrete types, and with and without an overlying water pool. Sensitivity studies were performed in a few cases involving, for example, heat transfer frommore » melt to concrete, condensed phase chemistry, etc. Further, special analysis was performed using the ACE L8 experimental data to illustrate the differences between the experimental and the reactor conditions, and to demonstrate that with proper corrections made to the code, the calculated results were in better agreement with the experimental data. Generally, in the case of dry cavity and metallic melts, CORCON-Mod3 thermal-hydraulic calculations were in good agreement with the test data. For oxidic melts in a dry cavity, uncertainties in heat transfer models played an important role for two melt configurations--a stratified geometry with segregated metal and oxide layers, and a heterogeneous mixture. Some discrepancies in the gas release data were noted in a few cases.« less

DOE Zero Energy Ready Home Case Study: Alliance Green Builders, Casa Aguila

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pacific Northwest National Laboratory

Alliance Green Builders built this 3,129-ft2 home in the hills above Ramona, California, to the high-performance criteria of the DOE Zero Energy Ready Home (ZERH) program. The home should perform far better than net zero thanks to a super-efficient building shell, a wind turbine, three suntracking solar photovoltaic arrays, and solar thermal water heating.

Fragmentation of DHS Public Corruption Investigations: Options to Leverage Overlapping Jurisdiction and Enhance Collaboration

DTIC Science & Technology

2011-12-01

LAPD Los Angeles Police Department MOU Memorandum of Understanding xii NCA National Crime Agency OIG Office of Inspector General OPR Office...that police departments should not be afforded the same privilege. In 2008, Ramona Ripston, Executive Director of the Los Angeles Chapter of the ...American Civil Liberties Union, praised outgoing Los Angeles Police Department ( LAPD ) Chief

Palynostratigraphy, palaeoclimates and palaeodepositional environments of the Miocene aged Agbada Formation in the Niger Delta, Nigeria

NASA Astrophysics Data System (ADS)

Bankole, Samson I.; Schrank, Eckart; Osterloff, Peter L.

2014-07-01

A diverse assemblage of palynomorphs dominated by terrestrially derived pollen and spores is reported from three wells penetrating the Miocene Agbada Formation. The pteridophyte and bryophyte spores which form the background assemblages in the three wells are good indicators of humid tropical climates which might have prevailed in the Niger Delta during the Miocene. The abundance and variations of climate-sensitive taxa including mangrove affiliated pollen and spore types Acrostichumsporites, Psilatricolporites crassus, Zonocostites ramonae and Graminidites annulatus representing the savannah vegetation cover indicate a complex interplay between periods of wetter and drier climates. Marine-derived dinoflagellate cysts and foraminiferal test linings are significantly present in the three wells. Taxa indicating freshwater contributions including Botryococcus spp., Chomotriletes minor, Ovoidites parvus and Pediastrum spp. are also represented numerically across the three wells. The presence of age diagnostic palynomorphs such as Crassoretitriletes vanraadshooveni, Retibrevitricolporites obodoensis, Tuberculodinium vancampoae, Zonocostites ramonae and Tuberculodinium vancampoae recovered in the three sections studied suggest a Miocene age for the investigated Agbada Formation. The proposed age is supported by the ranges of key palynomorphs in contemporaneous basins in Africa, northern South America and other parts of the World.

Track-structure simulations for charged particles.

PubMed

Dingfelder, Michael

2012-11-01

Monte Carlo track-structure simulations provide a detailed and accurate picture of radiation transport of charged particles through condensed matter of biological interest. Liquid water serves as a surrogate for soft tissue and is used in most Monte Carlo track-structure codes. Basic theories of radiation transport and track-structure simulations are discussed and differences compared to condensed history codes highlighted. Interaction cross sections for electrons, protons, alpha particles, and light and heavy ions are required input data for track-structure simulations. Different calculation methods, including the plane-wave Born approximation, the dielectric theory, and semi-empirical approaches are presented using liquid water as a target. Low-energy electron transport and light ion transport are discussed as areas of special interest.

Boromuscovite, a new member of the mica group, from the Little Three mine pegmatite, Ramona district, San Diego County, California

USGS Publications Warehouse

Foord, E.E.; Martin, R.F.; Fitzpatrick, J.J.; Taggart, J.E.; Crock, J.G.

1991-01-01

Boromuscovite, ideally KAl2(Si3B)O10(OH,F)2, in which [4]Al is replaced by B relative to muscovite, occurs as a late-stage, postpocket rupture mineral within the New Spaulding Pocket, main Little Three pegmatite dike. The mineral is white to cream colored and occurs as a porcelaneous veneer and coating on primary minerals. The average grain size is less than 3-4 ??m, but the coatings may be as much as 1 cm or more thick. Fragments of topaz, albite, elbaite, and other pocket minerals are included in the coating. The boromuscovite precipitated from a late-stage hydothermal fluid; it occurs only as a snowlike coating. Chemical composition, unit-cell parameters, Mohs hardness, cleavage, fracture, and optical properties are reported. -from Authors

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, Lorraine M.

This report describes groundwater monitoring in 2014 for the property at Ramona, Kansas, on which a grain storage facility was formerly operated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The monitoring was implemented on behalf of the CCC/USDA by Argonne National Laboratory and was conducted as specified in the Long-Term Groundwater Monitoring Plan (Argonne 2012) approved by the Kansas Department of Health and Environment (KDHE 2012).

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, Lorraine M.

This Monitoring Report describes groundwater monitoring for the property at Ramona, Kansas, on which a grain storage facility was formerly operated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The monitoring was implemented on behalf of the CCC/USDA by Argonne National Laboratory. Monitoring was conducted as specified in the Long-Term Groundwater Monitoring Plan (Argonne 2012) approved by the Kansas Department of Health and Environment (KDHE 2012).

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, Lorraine M.

This report describes groundwater monitoring in 2015 for the property at Ramona, Kansas, on which a grain storage facility was formerly operated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA). The monitoring was implemented on behalf of the CCC/USDA by Argonne National Laboratory and was conducted as specified in the Long-Term Groundwater Monitoring Plan (Argonne 2012) approved by the Kansas Department of Health and Environment (KDHE 2012).

Development of a model and computer code to describe solar grade silicon production processes

NASA Technical Reports Server (NTRS)

Srivastava, R.; Gould, R. K.

1979-01-01

Mathematical models, and computer codes based on these models were developed which allow prediction of the product distribution in chemical reactors in which gaseous silicon compounds are converted to condensed phase silicon. The reactors to be modeled are flow reactors in which silane or one of the halogenated silanes is thermally decomposed or reacted with an alkali metal, H2 or H atoms. Because the product of interest is particulate silicon, processes which must be modeled, in addition to mixing and reaction of gas-phase reactants, include the nucleation and growth of condensed Si via coagulation, condensation, and heterogeneous reaction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

LaFreniere, L. M.

This Work Plan outlines the scope of work that will be conducted to investigate the subsurface contaminant conditions at the property formerly leased by the Commodity Credit Corporation (CCC) in Ramona, Kansas (Figure 1.1). Data obtained during this event will be used to (1) evaluate potential source areas on the property, (2) determine the vertical and horizontal extent of potential contamination, and (3) provide recommendations for future actions, with the ultimate goal of assigning this site No Further Action status. The planned investigation includes groundwater monitoring requested by the Kansas Department of Health and Environment (KDHE), in accordance with Sectionmore » V of the Intergovernmental Agreement between the KDHE and the Farm Service Agency of the United States Department of Agriculture (USDA). The work is being performed on behalf of the CCC/USDA by the Environmental Research Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy. Under the Intergovernmental Agreement, Argonne provides technical assistance to the CCC/USDA with environmental site characterization and remediation at former CCC/USDA grain storage facilities. Argonne has issued a Master Work Plan (Argonne 2002) that describes the general scope of all investigations at former CCC/USDA facilities in Kansas and provides guidance for these investigations. The Master Work Plan was approved by the KDHE. It contains materials common to investigations at locations in Kansas and should be consulted for the complete details of plans for work associated with the former CCC/USDA facility at Ramona.« less

Development of a Model and Computer Code to Describe Solar Grade Silicon Production Processes

NASA Technical Reports Server (NTRS)

Srivastava, R.; Gould, R. K.

1979-01-01

The program aims at developing mathematical models and computer codes based on these models, which allow prediction of the product distribution in chemical reactors for converting gaseous silicon compounds to condensed-phase silicon. The major interest is in collecting silicon as a liquid on the reactor walls and other collection surfaces. Two reactor systems are of major interest, a SiCl4/Na reactor in which Si(l) is collected on the flow tube reactor walls and a reactor in which Si(l) droplets formed by the SiCl4/Na reaction are collected by a jet impingement method. During this quarter the following tasks were accomplished: (1) particle deposition routines were added to the boundary layer code; and (2) Si droplet sizes in SiCl4/Na reactors at temperatures below the dew point of Si are being calculated.

Modeling of local steam condensation on walls in presence of non-condensable gases. Application to a loca calculation in reactor containment using the multidimensional geyser/tonus code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benet, L.V.; Caroli, C.; Cornet, P.

1995-09-01

This paper reports part of a study of possible severe pressurized water reactor (PWR) accidents. The need for containment modeling, and in particular for a hydrogen risk study, was reinforced in France after 1990, with the requirement that severe accidents must be taken into account in the design of future plants. This new need of assessing the transient local hydrogen concentration led to the development, in the Mechanical Engineering and Technology Department of the French Atomic Energy Commission (CEA/DMT), of the multidimensional code GEYSER/TONUS for containment analysis. A detailed example of the use of this code is presented. The mixturemore » consisted of noncondensable gases (air or air plus hydrogen) and water vapor and liquid water. This is described by a compressible homogeneous two-phase flow model and wall condensation is based on the Chilton-Colburn formula and the analogy between heat and mass transfer. Results are given for a transient two-dimensional axially-symmetric computation for the first hour of a simplified accident sequence. In this there was an initial injection of a large amount of water vapor followed by a smaller amount and by hydrogen injection.« less

Subgrid-scale Condensation Modeling for Entropy-based Large Eddy Simulations of Clouds

NASA Astrophysics Data System (ADS)

Kaul, C. M.; Schneider, T.; Pressel, K. G.; Tan, Z.

2015-12-01

An entropy- and total water-based formulation of LES thermodynamics, such as that used by the recently developed code PyCLES, is advantageous from physical and numerical perspectives. However, existing closures for subgrid-scale thermodynamic fluctuations assume more traditional choices for prognostic thermodynamic variables, such as liquid potential temperature, and are not directly applicable to entropy-based modeling. Since entropy and total water are generally nonlinearly related to diagnosed quantities like temperature and condensate amounts, neglecting their small-scale variability can lead to bias in simulation results. Here we present the development of a subgrid-scale condensation model suitable for use with entropy-based thermodynamic formulations.

Testimony of E. Ramona Trovato, Deputy Assistant Administrator, Office of Environmental Information, U.S. Environmental Protection Agency before the Committee on Environment and Public Works, United States Senate.

ERIC Educational Resources Information Center

2002

This testimony provides an overview of health and environmental issues in U.S. schools and describes efforts by the Environmental Protection Agency (EPA), in concert with other federal agencies, to help schools address environmental issues. These include the Clear Skies Initiative, Indoor Air Quality Tools for Schools, High Performance Schools,…

Analysis of PANDA Passive Containment Cooling Steady-State Tests with the Spectra Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stempniewicz, Marek M

2000-07-15

Results of post test simulation of the PANDA passive containment cooling (PCC) steady-state tests (S-series tests), performed at the PANDA facility at the Paul Scherrer Institute, Switzerland, are presented. The simulation has been performed using the computer code SPECTRA, a thermal-hydraulic code, designed specifically for analyzing containment behavior of nuclear power plants.Results of the present calculations are compared to the measurement data as well as the results obtained earlier with the codes MELCOR, TRAC-BF1, and TRACG. The calculated PCC efficiencies are somewhat lower than the measured values. Similar underestimation of PCC efficiencies had been obtained in the past, with themore » other computer codes. To explain this difference, it is postulated that condensate coming into the tubes forms a stream of liquid in one or two tubes, leaving most of the tubes unaffected. The condensate entering the water box is assumed to fall down in the form of droplets. With these assumptions, the results calculated with SPECTRA are close to the experimental data.It is concluded that the SPECTRA code is a suitable tool for analyzing containments of advanced reactors, equipped with passive containment cooling systems.« less

Incorporation of Condensation Heat Transfer in a Flow Network Code

NASA Technical Reports Server (NTRS)

Anthony, Miranda; Majumdar, Alok

2002-01-01

Pure water is distilled from waste water in the International Space Station. The distillation assembly consists of an evaporator, a compressor and a condenser. Vapor is periodically purged from the condenser to avoid vapor accumulation. Purged vapor is condensed in a tube by coolant water prior to entering the purge pump. The paper presents a condensation model of purged vapor in a tube. This model is based on the Finite Volume Method. In the Finite Volume Method, the flow domain is discretized into multiple control volumes and a simultaneous analysis is performed.

COMMIX-PPC: A three-dimensional transient multicomponent computer program for analyzing performance of power plant condensers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chien, T.H.; Domanus, H.M.; Sha, W.T.

1993-02-01

The COMMIX-PPC computer pregrain is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex Industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional equations of conservation of mass, momentum, and energy on the tube stile and the proper accounting for the thermal interaction between shell and tube side through the porous-medium approach. The other added featuremore » is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient. Three-dimensional analysis of fluid flow with heat transfer tn a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification, it can be used to analyze processes in any heat exchanger or other single-phase engineering applications. Volume I (Equations and Numerics) of this report describes in detail the basic equations, formulation, solution procedures, and models for a phenomena. Volume II (User's Guide and Manual) contains the input instruction, flow charts, sample problems, and descriptions of available options and boundary conditions.« less

Equilibrium chemistry down to 100 K. Impact of silicates and phyllosilicates on the carbon to oxygen ratio

NASA Astrophysics Data System (ADS)

Woitke, P.; Helling, Ch.; Hunter, G. H.; Millard, J. D.; Turner, G. E.; Worters, M.; Blecic, J.; Stock, J. W.

2018-06-01

We have introduced a fast and versatile computer code, GGCHEM, to determine the chemical composition of gases in thermo-chemical equilibrium down to 100 K, with or without equilibrium condensation. We have reviewed the data for molecular equilibrium constants, kp(T), from several sources and discussed which functional fits are most suitable for low temperatures. We benchmarked our results against another chemical equilibrium code. We collected Gibbs free energies, ΔGf⊖, for about 200 solid and liquid species from the NIST-JANAF database and the geophysical database SUPCRTBL. We discussed the condensation sequence of the elements with solar abundances in phase equilibrium down to 100 K. Once the major magnesium silicates Mg2SiO4[s] and MgSiO3[s] have formed, the dust to gas mass ratio jumps to a value of about 0.0045 which is significantly lower than the often assumed value of 0.01. Silicate condensation is found to increase the carbon to oxygen ratio (C/O) in the gas from its solar value of 0.55 up to 0.71, and, by the additional intake of water and hydroxyl into the solid matrix, the formation of phyllosilicates at temperatures below 400 K increases the gaseous C/O further to about 0.83. Metallic tungsten (W) is the first condensate found to become thermodynamically stable around 1600-2200 K (depending on pressure), several hundreds of Kelvin before subsequent materials such as zirconium dioxide (ZrO2) or corundum (Al2O3) can condense. We briefly discuss whether tungsten, despite its low abundance of 2 × 10-7 times the silicon abundance, could provide the first seed particles for astrophysical dust formation. GGCHEM code is publicly available at http://https://github.com/pw31/GGchemTable D.1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/A1

Parallel Numerical Simulations of Water Reservoirs

NASA Astrophysics Data System (ADS)

Torres, Pedro; Mangiavacchi, Norberto

2010-11-01

The study of the water flow and scalar transport in water reservoirs is important for the determination of the water quality during the initial stages of the reservoir filling and during the life of the reservoir. For this scope, a parallel 2D finite element code for solving the incompressible Navier-Stokes equations coupled with scalar transport was implemented using the message-passing programming model, in order to perform simulations of hidropower water reservoirs in a computer cluster environment. The spatial discretization is based on the MINI element that satisfies the Babuska-Brezzi (BB) condition, which provides sufficient conditions for a stable mixed formulation. All the distributed data structures needed in the different stages of the code, such as preprocessing, solving and post processing, were implemented using the PETSc library. The resulting linear systems for the velocity and the pressure fields were solved using the projection method, implemented by an approximate block LU factorization. In order to increase the parallel performance in the solution of the linear systems, we employ the static condensation method for solving the intermediate velocity at vertex and centroid nodes separately. We compare performance results of the static condensation method with the approach of solving the complete system. In our tests the static condensation method shows better performance for large problems, at the cost of an increased memory usage. Performance results for other intensive parts of the code in a computer cluster are also presented.

Mathematical Modeling of Loop Heat Pipes with Multiple Capillary Pumps and Multiple Condensers. Part 1; Stead State Stimulations

NASA Technical Reports Server (NTRS)

Hoang, Triem T.; OConnell, Tamara; Ku, Jentung

2004-01-01

Loop Heat Pipes (LHPs) have proven themselves as reliable and robust heat transport devices for spacecraft thermal control systems. So far, the LHPs in earth-orbit satellites perform very well as expected. Conventional LHPs usually consist of a single capillary pump for heat acquisition and a single condenser for heat rejection. Multiple pump/multiple condenser LHPs have shown to function very well in ground testing. Nevertheless, the test results of a dual pump/condenser LHP also revealed that the dual LHP behaved in a complicated manner due to the interaction between the pumps and condensers. Thus it is redundant to say that more research is needed before they are ready for 0-g deployment. One research area that perhaps compels immediate attention is the analytical modeling of LHPs, particularly the transient phenomena. Modeling a single pump/single condenser LHP is difficult enough. Only a handful of computer codes are available for both steady state and transient simulations of conventional LHPs. No previous effort was made to develop an analytical model (or even a complete theory) to predict the operational behavior of the multiple pump/multiple condenser LHP systems. The current research project offered a basic theory of the multiple pump/multiple condenser LHP operation. From it, a computer code was developed to predict the LHP saturation temperature in accordance with the system operating and environmental conditions.

Solving Guzman's Problem: "An Other" Narrative of "La Gran Familia Puertorriquena" in Judith Ortiz Cofer's "The Line of the Sun"

ERIC Educational Resources Information Center

Waldron, John V.

2009-01-01

The first half of Judith Ortiz Cofer's novel "The Line of the Sun" (1989) narrates events that take place in the small fictional town of Salud, Puerto Rico, during the 1940s and 50s. In the second part of the novel, starting with chapter six, the readers see how two characters from the first half, Rafael and Ramona, and their young…

An attempt to make a reliable assessment of the wet steam flow field in the de Laval nozzle

NASA Astrophysics Data System (ADS)

Dykas, Sławomir; Majkut, Mirosław; Smołka, Krystian; Strozik, Michał

2018-02-01

This paper presents the results of research on the wet steam flow with spontaneous condensation in the de Laval nozzle. A comparison is made between the results of numerical modelling performed for two cases of boundary conditions obtained using an in-house CFD code and the Ansys CFX commercial package. The numerical modelling results are compared to the results of experimental testing carried out on an in-house laboratory steam tunnel. The differences between the numerical results produced by the two codes in terms of place and intensity of condensations of steam to water point to the difficulty in correct modelling of this type of flows and emphasize the need for further studies in this field.

Repetition rates in heavy ion beam driven fusion reactors

NASA Astrophysics Data System (ADS)

Peterson, Robert R.

1986-01-01

The limits on the cavity gas density required for beam propagation and condensation times for material vaporized by target explosions can determine the maximum repetition rate of Heavy Ion Beam (HIB) driven fusion reactors. If the ions are ballistically focused onto the target, the cavity gas must have a density below roughly 10-4 torr (3×1012 cm-3) at the time of propagation; other propagation schemes may allow densities as high as 1 torr or more. In some reactor designs, several kilograms of material may be vaporized off of the target chamber walls by the target generated x-rays, raising the average density in the cavity to 100 tor or more. A one-dimensional combined radiation hydrodynamics and vaporization and condensation computer code has been used to simulate the behavior of the vaporized material in the target chambers of HIB fusion reactors.

Reaction path of energetic materials using THOR code

NASA Astrophysics Data System (ADS)

Duraes, L.; Campos, J.; Portugal, A.

1997-07-01

The method of predicting reaction path, using a thermochemical computer code, named THOR, 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 a thermal equation of state (EoS). The used HL EoS is a new EoS developed in previous works. HL EoS is supported by a Boltzmann EoS, taking α =13.5 to the exponent of the intermolecular potential and θ=1.4 to the adimensional temperature. This code allows now 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, described, calculated and discussed - Ammonium Nitrate based explosives and Nitromethane - because they are very known explosives and their equivalence ratio is respectively near and greater than the stoicheiometry. Predictions of detonation properties of other condensed explosives, as a function of energy release, present results in good correlation with experimental values.

Application of a single-fluid model for the steam condensing flow prediction

NASA Astrophysics Data System (ADS)

Smołka, K.; Dykas, S.; Majkut, M.; Strozik, M.

2016-10-01

One of the results of many years of research conducted in the Institute of Power Engineering and Turbomachinery of the Silesian University of Technology are computational algorithms for modelling steam flows with a non-equilibrium condensation process. In parallel with theoretical and numerical research, works were also started on experimental testing of the steam condensing flow. This paper presents a comparison of calculations of a flow field modelled by means of a single-fluid model using both an in-house CFD code and the commercial Ansys CFX v16.2 software package. The calculation results are compared to inhouse experimental testing.

COMMIX-PPC: A three-dimensional transient multicomponent computer program for analyzing performance of power plant condensers. Volume 1, Equations and numerics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chien, T.H.; Domanus, H.M.; Sha, W.T.

1993-02-01

The COMMIX-PPC computer pregrain is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex Industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional equations of conservation of mass, momentum, and energy on the tube stile and the proper accounting for the thermal interaction between shell and tube side through the porous-medium approach. The other added featuremore » is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient. Three-dimensional analysis of fluid flow with heat transfer tn a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification, it can be used to analyze processes in any heat exchanger or other single-phase engineering applications. Volume I (Equations and Numerics) of this report describes in detail the basic equations, formulation, solution procedures, and models for a phenomena. Volume II (User`s Guide and Manual) contains the input instruction, flow charts, sample problems, and descriptions of available options and boundary conditions.« less

Post-test analysis of PIPER-ONE PO-IC-2 experiment by RELAP5/MOD3 codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bovalini, R.; D`Auria, F.; Galassi, G.M.

1996-11-01

RELAP5/MOD3.1 was applied to the PO-IC-2 experiment performed in PIPER-ONE facility, which has been modified to reproduce typical isolation condenser thermal-hydraulic conditions. RELAP5 is a well known code widely used at the University of Pisa during the past seven years. RELAP5/MOD3.1 was the latest version of the code made available by the Idaho National Engineering Laboratory at the time of the reported study. PIPER-ONE is an experimental facility simulating a General Electric BWR-6 with volume and height scaling ratios of 1/2,200 and 1./1, respectively. In the frame of the present activity a once-through heat exchanger immersed in a pool ofmore » ambient temperature water, installed approximately 10 m above the core, was utilized to reproduce qualitatively the phenomenologies expected for the Isolation Condenser in the simplified BWR (SBWR). The PO-IC-2 experiment is the flood up of the PO-SD-8 and has been designed to solve some of the problems encountered in the analysis of the PO-SD-8 experiment. A very wide analysis is presented hereafter including the use of different code versions.« less

Biomass Economy

DTIC Science & Technology

1985-11-01

Boiler and Pressure Vessel Code HEI Heat Exchanger Institute Heat and Material Balance c. System Description (1) Condenser... Boiler and Pressure Vessel Code "AN(SI B31.1 Power Piping d. System Description (1) Deaerator The deaerator will be d direct contact feedwater heater, and...vent, and drain piping. "b . Applicable Codes ASME Boiler and Pressure Vessel Code "ANSI B31.1 - Power Piping Code

Space Technology Industry Forum

NASA Image and Video Library

2010-07-13

Ramona Travis, NASA Stennis Space Center Chief Technologist, speaks during the NASA New Space Technology Industry Forum being held at the University of Maryland in College Park on Wednesday, July 14, 2010. During the two-day event, speakers are focusing on the president's fiscal year 2011 budget request for NASA's new Space Technology Program. Representatives from industry, academia and the federal government are in attendance to discuss strategy, development and implementation of NASA's proposed new technology-enabled exploration. Photo Credit: (NASA/Carla Cioffi)

Palynology of carcinolites and limestones from the Baunilha Grande Ecofacies of the Pirabas Formation (Miocene of Pará state, northeastern Brazil)

NASA Astrophysics Data System (ADS)

Antonioli, Luzia; de Araújo Távora, Vladimir; Dino, Rodolfo

2015-10-01

The Pirabas Formation records important transgressive/regressive marine events in northern Brazil during the Miocene. Here, we present the results of a palynological analysis of four samples from finely stratified gray limestone and associated carbonate concretions bearing decapod crustacean remains. These sampled strata are representatives of the Baunilha Grande Ecofacies, and our analysis enhances the knowledge of local biostratigraphy and paleoecology. The palynoflora is dominated by taxa typical of Neogene tropical areas, such as Zonocostites ramonae (the most common species), together with Retitricolpites and Retitricolporites genera. Commonly represented are the smooth and apiculate trilete/monolete spores (Polypodiisporites, Verrucosisporites, Magnastriatites, and Deltoidospora), in conjunction with some freshwater algae (Ovoidites and Botryococcus). Gymnosperm pollen grains were absent. Marine microplankton (dinoflagellate cysts, acritarchs and foraminiferal test linings) are scarce, although present in all samples. The presence of the index species, Malvacipolloides maristellae and Pachydermites diederixii, co-occurring with Zonocostites ramonae and Lanagiopollis crassa, suggests that these sediments and concretions belong to the "T-13 Malvacipolloides maristellae" palynozone (Jaramillo et al., 2011), considered as late-Early Miocene in age. Palynological and sedimentological evidence further points to a predominantly continental depositional environment with a weak marine influence, as indicated by the persistent presence of sparse dinoflagellate cysts, acritarchs and foraminiferal test linings, typical of a mangrove environment.

Fast emission spectroscopy for monitoring condensed carbon in detonation products of oxygen-deficient high explosives

NASA Astrophysics Data System (ADS)

Poeuf, Sandra; Baudin, Gerard; Genetier, Marc; Lefrançois, Alexandre; Cinnayya, Ashwin; Laurent, Jacquet

2017-06-01

A new thermochemical code, SIAME, dedicated to the study of high explosives, is currently being developed. New experimental data relative to the expansion of detonation products are required to validate the code, and a particular focus is made on solid carbon products. Two different high explosive formulations are used: a melt-cast one (RDX/TNT 60/40 % wt.) and a pressed one (HMX/VitonR 96/4 % wt.). The experimental setup allows the expansion of the products at pressures below 1 GPa in an inert medium (vacuum, helium, nitrogen and PMMA). The results of fast emission dynamic spectroscopy measurements used to monitor the detonation carbon products are reported. Two spectral signatures are identified: the first is associated to ionized gases and the second to carbon thermal radiation. The experimental spectral lines are compared with simulated spectra. The trajectory of the shock wave front is continuously recorded with a high frequency interferometer. Comparisons with numerical simulations on the hydrodynamic code Ouranoshave been done. These two measurements, using the different inert media, enable to make one step forward in the validation of the detonation products equation of state implemented in the SIAME code.

Optical properties of potential condensates in exoplanetary atmospheres

NASA Astrophysics Data System (ADS)

Kitzmann, Daniel; Heng, Kevin

2018-03-01

The prevalence of clouds in currently observable exoplanetary atmospheres motivates the compilation and calculation of their optical properties. First, we present a new open-source Mie scattering code known as LX-MIE, which is able to consider large-size parameters (˜107) using a single computational treatment. We validate LX-MIE against the classical MIEVO code as well as previous studies. Secondly, we embark on an expanded survey of the published literature for both the real and imaginary components of the refractive indices of 32 condensate species. As much as possible, we rely on experimental measurements of the refractive indices and resort to obtaining the real from the imaginary component (or vice versa), via the Kramers-Kronig relation, only in the absence of data. We use these refractive indices as input for LX-MIE to compute the absorption, scattering and extinction efficiencies of all 32 condensate species. Finally, we use a three-parameter function to provide convenient fits to the shape of the extinction efficiency curve. We show that the errors associated with these simple fits in the Wide Field Camera 3 (WFC3), J, H, and K wavebands are ˜ 10 per cent. These fits allow for the extinction cross-section or opacity of the condensate species to be easily included in retrieval analyses of transmission spectra. We discuss prospects for future experimental work. The compilation of the optical constants and LX-MIE is publicly available as part of the open-source Exoclime Simulation Platform (http://www.exoclime.org).

NUMERICAL TECHNIQUES TO SOLVE CONDENSATIONAL AND DISSOLUTIONAL GROWTH EQUATIONS WHEN GROWTH IS COUPLED TO REVERSIBLE REACTIONS (R823186)

EPA Science Inventory

Noniterative, unconditionally stable numerical techniques for solving condensational and
dissolutional growth equations are given. Growth solutions are compared to Gear-code solutions for
three cases when growth is coupled to reversible equilibrium chemistry. In all cases, ...

Event-by-Event Simulations of Early Gluon Fields in High Energy Nuclear Collisions

NASA Astrophysics Data System (ADS)

Nickel, Matthew; Rose, Steven; Fries, Rainer

2017-09-01

Collisions of heavy ions are carried out at ultra relativistic speeds at the Relativistic Heavy Ion Collider and the Large Hadron Collider to create Quark Gluon Plasma. The earliest stages of such collisions are dominated by the dynamics of classical gluon fields. The McLerran-Venugopalan (MV) model of color glass condensate provides a model for this process. Previous research has provided an analytic solution for event averaged observables in the MV model. Using the High Performance Research Computing Center (HPRC) at Texas A&M, we have developed a C++ code to explicitly calculate the initial gluon fields and energy momentum tensor event by event using the analytic recursive solution. The code has been tested against previously known analytic results up to fourth order. We have also have been able to test the convergence of the recursive solution at high orders in time and studied the time evolution of color glass condensate.

TRAC-PF1 code verification with data from the OTIS test facility. [Once-Through Intergral System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Childerson, M.T.; Fujita, R.K.

1985-01-01

A computer code (TRAC-PF1/MOD1) developed for predicting transient thermal and hydraulic integral nuclear steam supply system (NSSS) response was benchmarked. Post-small break loss-of-coolant accident (LOCA) data from a scaled, experimental facility, designated the One-Through Integral System (OTIS), were obtained for the Babcock and Wilcox NSSS and compared to TRAC predictions. The OTIS tests provided a challenging small break LOCA data set for TRAC verification. The major phases of a small break LOCA observed in the OTIS tests included pressurizer draining and loop saturation, intermittent reactor coolant system circulation, boiler-condenser mode, and the initial stages of refill. The TRAC code wasmore » successful in predicting OTIS loop conditions (system pressures and temperatures) after modification of the steam generator model. In particular, the code predicted both pool and auxiliary-feedwater initiated boiler-condenser mode heat transfer.« less

George Andrew Olah - Patents

Science.gov Websites

Additional Information US 4,394,247 LIQUEFACTION OF COALS USING RECYCLABLE SUPERACID CATALYST - Olah, George catalytic condensation using superacid catalysts. US 4,465,893 OXIDATIVE CONDENSATION OF NATURAL GAS OR ., synthetic transportation fuels or lower olefins) via catalytic condensation using superacid catalysts. US

Acoustically Forced Coaxial Hydrogen/Liquid Oxygen Jet Flames

DTIC Science & Technology

2016-05-15

Briefing Charts 3. DATES COVERED (From - To) 25 April 2016 - 15 May 2016 4. TITLE AND SUBTITLE Acoustically Forced Coaxial Hydrogen / Liquid Oxygen Jet...area code) N/A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 1 Acoustically Forced Coaxial Hydrogen / Liquid Oxygen Jet Flames...propellants be stored in condensed form – e.g., kerosene, liquid oxygen in rockets • Combustion systems can no longer be designed to meet modern

Stable chromosome condensation revealed by chromosome conformation capture

PubMed Central

Eagen, Kyle P.; Hartl, Tom A.; Kornberg, Roger D.

2015-01-01

SUMMARY Chemical cross-linking and DNA sequencing have revealed regions of intra-chromosomal interaction, referred to as topologically associating domains (TADs), interspersed with regions of little or no interaction, in interphase nuclei. We find that TADs and the regions between them correspond with the bands and interbands of polytene chromosomes of Drosophila. We further establish the conservation of TADs between polytene and diploid cells of Drosophila. From direct measurements on light micrographs of polytene chromosomes, we then deduce the states of chromatin folding in the diploid cell nucleus. Two states of folding, fully extended fibers containing regulatory regions and promoters, and fibers condensed up to ten-fold containing coding regions of active genes, constitute the euchromatin of the nuclear interior. Chromatin fibers condensed up to 30-fold, containing coding regions of inactive genes, represent the heterochromatin of the nuclear periphery. A convergence of molecular analysis with direct observation thus reveals the architecture of interphase chromosomes. PMID:26544940

Study of steam condensation at sub-atmospheric pressure: setting a basic research using MELCOR code

NASA Astrophysics Data System (ADS)

Manfredini, A.; Mazzini, M.

2017-11-01

One of the most serious accidents that can occur in the experimental nuclear fusion reactor ITER is the break of one of the headers of the refrigeration system of the first wall of the Tokamak. This results in water-steam mixture discharge in vacuum vessel (VV), with consequent pressurization of this container. To prevent the pressure in the VV exceeds 150 KPa absolute, a system discharges the steam inside a suppression pool, at an absolute pressure of 4.2 kPa. The computer codes used to analyze such incident (eg. RELAP 5 or MELCOR) are not validated experimentally for such conditions. Therefore, we planned a basic research, in order to have experimental data useful to validate the heat transfer correlations used in these codes. After a thorough literature search on this topic, ACTA, in collaboration with the staff of ITER, defined the experimental matrix and performed the design of the experimental apparatus. For the thermal-hydraulic design of the experiments, we executed a series of calculations by MELCOR. This code, however, was used in an unconventional mode, with the development of models suited respectively to low and high steam flow-rate tests. The article concludes with a discussion of the placement of experimental data within the map featuring the phenomenon characteristics, showing the importance of the new knowledge acquired, particularly in the case of chugging.

Thermal Integration of a Liquid Acquisition Device into a Cryogenic Feed System

NASA Technical Reports Server (NTRS)

Hastings, L. J.; Bolshinskiy, L. G.; Schunk, R. G.; Martin, A. K.; Eskridge, R. H.; Frenkel, A.; Grayson, G.; Pendleton, M. L.

2011-01-01

Primary objectives of this effort were to define the following: (1) Approaches for quantification of the accumulation of thermal energy within a capillary screen liquid acquisition device (LAD) for a lunar lander upper stage during periods of up to 210 days on the lunar surface, (2) techniques for mitigating heat entrapment, and (3) perform initial testing, data evaluation. The technical effort was divided into the following categories: (1) Detailed thermal modeling of the LAD/feed system interactions using both COMSOL computational fluid device and standard codes, (2) FLOW-3D modeling of bulk liquid to provide interfacing conditions for the LAD thermal modeling, (3) condensation conditioning of capillary screens to stabilize surface tension retention capability, and (4) subscale testing of an integrated LAD/feed system. Substantial progress was achieved in the following technical areas: (1) Thermal modeling and experimental approaches for evaluating integrated cryogen LAD/feed systems, at both the system and component levels, (2) reduced gravity pressure control analyses, (3) analytical modeling and testing for capillary screen conditioning using condensation and wicking, and (4) development of rapid turnaround testing techniques for evaluating LAD/feed system thermal and fluid integration. A comprehensive effort, participants included a diverse cross section of representatives from academia, contractors, and multiple Marshall Space Flight Center organizations.

Jovian Tropospheric Photohemistry: Constraints from Recent Cassini and Galileo Observations and from Laboratory Experiment Simulations

NASA Astrophysics Data System (ADS)

Moses, Julianne I.; Sperier, A. D.; Keane, T. C.

2008-09-01

We use the Caltech/JPL KINETICS code (Allen et al. 1981, JGR 86, 3617) to develop 1-D (in altitude) photochemical models for Jupiter's troposphere that are consistent with available Cassini, Galileo, Voyager, and Earth-based observations of ammonia and phosphine, and upper limits for HCN. As a test of the adopted chemical reaction list, we simulate laboratory experiments of coupled NH3-PH3 and NH3-C2H2 photochemistry (Ferris et al. 1984, J. Am. Chem. Soc. 106, 318; Ferris and Ishikawa 1988, J. Am. Chem. Soc. 110, 4306; Keane et al. 1996, Icarus 122, 205). We find that the vertical profile of PH3 is sensitive to the assumed tropospheric eddy diffusion coefficient and aerosol extinction, both of which are loosely constrained by observations and seem to vary with latitude. The NH3 profile is controlled by condensation and is relatively insensitive to the eddy diffusion coefficient. As was determined by previous photochemical models, the dominant products of Jovian tropospheric chemistry are P2H4, N2H4, red phosphorus, NH2PH2, and N2. All of these species except N2 will condense. Diphosphine (P2H4) is an underappreciated condensate that will likely be more important than N2H4 as an aerosol component on Jupiter as well as Saturn. Little is known about the chemistry and properties of NH2PH2, but this product could also be an important condensable constituent. Coupled NH3-C2H2 photochemistry does not readily occur in Jupiter's troposphere due to the low predicted (and observed) tropospheric C2H2 abundance. The models therefore produce only a small amount of HCN (well within upper limits), and even smaller amounts of the nitriles, hydrazones, and other organo-nitrogen molecules identified in the laboratory experiments mentioned above. This work was supported by the NASA Planetary Atmospheres Program (NNX08AF05G) and the Lunar and Planetary Institute/USRA.

Breath condenser coatings affect measurement of biomarkers in exhaled breath condensate.

PubMed

Rosias, P P; Robroeks, C M; Niemarkt, H J; Kester, A D; Vernooy, J H; Suykerbuyk, J; Teunissen, J; Heynens, J; Hendriks, H J; Jöbsis, Q; Dompeling, E

2006-11-01

Exhaled breath condensate collection is not yet standardised and biomarker measurements are often close to lower detection limits. In the current study, it was hypothesised that adhesive properties of different condenser coatings interfere with measurements of eicosanoids and proteins in breath condensate. In vitro, condensate was derived from a collection model using two test solutions (8-isoprostane and albumin) and five condenser coatings (silicone, glass, aluminium, polypropylene and Teflon). In vivo, condensate was collected using these five coatings and the EcoScreen condenser to measure 8-isoprostane, and three coatings (silicone, glass, EcoScreen) to measure albumin. In vitro, silicone and glass coatings had significantly higher albumin recovery compared with the other coatings. A similar trend was observed for 8-isoprostane recovery. In vivo, median (interquartile range) 8-isoprostane concentrations were significantly higher using silicone (9.2 (18.8) pg.mL(-1)) or glass (3.0 (4.5) pg.mL(-1)) coating, compared with aluminium (0.5 (2.4) pg.mL(-1)), polypropylene (0.5 (0.5) pg.mL(-1)), Teflon (0.5 (0.0) pg.mL(-1)), and EcoScreen (0.5 (2.0) pg.mL(-1)). Albumin in vivo was mainly detectable using glass coating. In conclusion, a condenser with silicone or glass coating is more efficient for measurement of 8-isoprostane or albumin in exhaled breath condensate, than EcoScreen, aluminium, polypropylene or Teflon. Guidelines for exhaled breath condensate standardisation should include the most valid condenser coating to measure a specific biomarker.

Exploring Antarctic Land Surface Temperature Extremes Using Condensed Anomaly Databases

NASA Astrophysics Data System (ADS)

Grant, Glenn Edwin

Satellite observations have revolutionized the Earth Sciences and climate studies. However, data and imagery continue to accumulate at an accelerating rate, and efficient tools for data discovery, analysis, and quality checking lag behind. In particular, studies of long-term, continental-scale processes at high spatiotemporal resolutions are especially problematic. The traditional technique of downloading an entire dataset and using customized analysis code is often impractical or consumes too many resources. The Condensate Database Project was envisioned as an alternative method for data exploration and quality checking. The project's premise was that much of the data in any satellite dataset is unneeded and can be eliminated, compacting massive datasets into more manageable sizes. Dataset sizes are further reduced by retaining only anomalous data of high interest. Hosting the resulting "condensed" datasets in high-speed databases enables immediate availability for queries and exploration. Proof of the project's success relied on demonstrating that the anomaly database methods can enhance and accelerate scientific investigations. The hypothesis of this dissertation is that the condensed datasets are effective tools for exploring many scientific questions, spurring further investigations and revealing important information that might otherwise remain undetected. This dissertation uses condensed databases containing 17 years of Antarctic land surface temperature anomalies as its primary data. The study demonstrates the utility of the condensate database methods by discovering new information. In particular, the process revealed critical quality problems in the source satellite data. The results are used as the starting point for four case studies, investigating Antarctic temperature extremes, cloud detection errors, and the teleconnections between Antarctic temperature anomalies and climate indices. The results confirm the hypothesis that the condensate databases are a highly useful tool for Earth Science analyses. Moreover, the quality checking capabilities provide an important method for independent evaluation of dataset veracity.

Recent MELCOR and VICTORIA Fission Product Research at the NRC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bixler, N.E.; Cole, R.K.; Gauntt, R.O.

1999-01-21

The MELCOR and VICTORIA severe accident analysis codes, which were developed at Sandia National Laboratories for the U. S. Nuclear Regulatory Commission, are designed to estimate fission product releases during nuclear reactor accidents in light water reactors. MELCOR is an integrated plant-assessment code that models the key phenomena in adequate detail for risk-assessment purposes. VICTORIA is a more specialized fission- product code that provides detailed modeling of chemical reactions and aerosol processes under the high-temperature conditions encountered in the reactor coolant system during a severe reactor accident. This paper focuses on recent enhancements and assessments of the two codes inmore » the area of fission product chemistry modeling. Recently, a model for iodine chemistry in aqueous pools in the containment building was incorporated into the MELCOR code. The model calculates dissolution of iodine into the pool and releases of organic and inorganic iodine vapors from the pool into the containment atmosphere. The main purpose of this model is to evaluate the effect of long-term revolatilization of dissolved iodine. Inputs to the model include dose rate in the pool, the amount of chloride-containing polymer, such as Hypalon, and the amount of buffering agents in the containment. Model predictions are compared against the Radioiodine Test Facility (RTF) experiments conduced by Atomic Energy of Canada Limited (AECL), specifically International Standard Problem 41. Improvements to VICTORIA's chemical reactions models were implemented as a result of recommendations from a peer review of VICTORIA that was completed last year. Specifically, an option is now included to model aerosols and deposited fission products as three condensed phases in addition to the original option of a single condensed phase. The three-condensed-phase model results in somewhat higher predicted fission product volatilities than does the single-condensed-phase model. Modeling of U02 thermochemistry was also improved, and results in better prediction of vaporization of uranium from fuel, which can react with released fission products to affect their volatility. This model also improves the prediction of fission product release rates from fuel. Finally, recent comparisons of MELCOR and VICTORIA with International Standard Problem 40 (STORM) data are presented. These comparisons focus on predicted therrnophoretic deposition, which is the dominant deposition mechanism. Sensitivity studies were performed with the codes to examine experimental and modeling uncertainties.« less

TopoMS: Comprehensive topological exploration for molecular and condensed-matter systems.

PubMed

Bhatia, Harsh; Gyulassy, Attila G; Lordi, Vincenzo; Pask, John E; Pascucci, Valerio; Bremer, Peer-Timo

2018-06-15

We introduce TopoMS, a computational tool enabling detailed topological analysis of molecular and condensed-matter systems, including the computation of atomic volumes and charges through the quantum theory of atoms in molecules, as well as the complete molecular graph. With roots in techniques from computational topology, and using a shared-memory parallel approach, TopoMS provides scalable, numerically robust, and topologically consistent analysis. TopoMS can be used as a command-line tool or with a GUI (graphical user interface), where the latter also enables an interactive exploration of the molecular graph. This paper presents algorithmic details of TopoMS and compares it with state-of-the-art tools: Bader charge analysis v1.0 (Arnaldsson et al., 01/11/17) and molecular graph extraction using Critic2 (Otero-de-la-Roza et al., Comput. Phys. Commun. 2014, 185, 1007). TopoMS not only combines the functionality of these individual codes but also demonstrates up to 4× performance gain on a standard laptop, faster convergence to fine-grid solution, robustness against lattice bias, and topological consistency. TopoMS is released publicly under BSD License. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Benchmarking of Improved DPAC Transient Deflagration Analysis Code

DOE PAGES

Laurinat, James E.; Hensel, Steve J.

2017-09-27

The deflagration pressure analysis code (DPAC) has been upgraded for use in modeling hydrogen deflagration transients. The upgraded code is benchmarked using data from vented hydrogen deflagration tests conducted at the HYDRO-SC Test Facility at the University of Pisa. DPAC originally was written to calculate peak pressures for deflagrations in radioactive waste storage tanks and process facilities at the Savannah River Site. Upgrades include the addition of a laminar flame speed correlation for hydrogen deflagrations and a mechanistic model for turbulent flame propagation, incorporation of inertial effects during venting, and inclusion of the effect of water vapor condensation on vesselmore » walls. In addition, DPAC has been coupled with chemical equilibrium with applications (CEA), a NASA combustion chemistry code. The deflagration tests are modeled as end-to-end deflagrations. As a result, the improved DPAC code successfully predicts both the peak pressures during the deflagration tests and the times at which the pressure peaks.« less

Benchmarking of Improved DPAC Transient Deflagration Analysis Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laurinat, James E.; Hensel, Steve J.

The deflagration pressure analysis code (DPAC) has been upgraded for use in modeling hydrogen deflagration transients. The upgraded code is benchmarked using data from vented hydrogen deflagration tests conducted at the HYDRO-SC Test Facility at the University of Pisa. DPAC originally was written to calculate peak pressures for deflagrations in radioactive waste storage tanks and process facilities at the Savannah River Site. Upgrades include the addition of a laminar flame speed correlation for hydrogen deflagrations and a mechanistic model for turbulent flame propagation, incorporation of inertial effects during venting, and inclusion of the effect of water vapor condensation on vesselmore » walls. In addition, DPAC has been coupled with chemical equilibrium with applications (CEA), a NASA combustion chemistry code. The deflagration tests are modeled as end-to-end deflagrations. As a result, the improved DPAC code successfully predicts both the peak pressures during the deflagration tests and the times at which the pressure peaks.« less

Collecting exhaled breath condensate (EBC) with two condensers in series: a promising technique for studying the mechanisms of EBC formation, and the volatility of selected biomarkers.

PubMed

Corradi, Massimo; Goldoni, Matteo; Caglieri, Andrea; Folesani, Giuseppina; Poli, Diana; Corti, Marina; Mutti, Antonio

2008-03-01

Exhaled breath condensate (EBC) consists mainly of water, but also contains semivolatile and nonvolatile compounds. The aim of this study was to develop a system in which two condensers are simultaneously used in series to clarify the mechanisms of EBC condensation. Two aliquots of EBC (EBC1 and EBC2) were collected from 20 asymptomatic smokers and 20 healthy young nonsmokers using a specifically designed device having two condensers in series in which total volume, hydrogen peroxide (H(2)O(2)), ammonium (NH(4)(+)), and conductivity before and after lyophilization were measured. Water, NH(4)(+) levels and conductivity before lyophilization were significantly lower in the EBC2 than in the EBC1 of smokers and nonsmokers; the contrary was true for H(2)O(2) levels. Almost all nonvolatile salts were collected in the first condenser, because more than 50% of postlyophilization conductivity was below the detection limit in EBC2. The recovery of volatile molecules and their derivatives (water and NH(4)(+)) was partial in the first condenser, but appreciable amounts of both were measured in the second; however, the condenser immediately in contact with exhaled air was more efficient in terms of water, NH(4)(+) and conductivity before lyophilization. On the contrary, nonvolatile ions (conductivity after lyophilization) were mainly collected in the first condenser. Finally, the behavior of H(2)O(2) cannot be explained on the basis of its chemical and physical properties, and the most probable explanation is that some was byproduced by a radical reaction in the gas phase or during the condensation process in water.

Limitation of Hot-Carrier Generated Heat Dissipation on the Frequency of Operation and Reliability of Novel Nitride-Based High-Speed HFETs

DTIC Science & Technology

2012-01-18

Ni, H. Morkoç, “Signature of hot phonons in reliability of nitride HFETs and signal delay” Acta Physica Polonica A. 119(2) 225-227 (2011) 27. L...lines in AlInN/GaN heterostructures”, Acta Physica Polonica A. 119(2) 173-175 (2011) 29. J. H. Leach, M. Wu, H. Morkoç, M. Ramonas, and A. Matulionis...Ardaraviius¤, O. Kiprijanovi, and J. Liberis, “Hot-Phonon Decided Carrier Velocity in AlInN/GaN Based Two-Dimensional Channels” Acta Physica

Characterization of open-cycle coal-fired MHD generators. Quarterly technical summary report No. 6, October 1--December 31, 1977. [PACKAGE code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolb, C.E.; Yousefian, V.; Wormhoudt, J.

1978-01-30

Research has included theoretical modeling of important plasma chemical effects such as: conductivity reductions due to condensed slag/electron interactions; conductivity and generator efficiency reductions due to the formation of slag-related negative ion species; and the loss of alkali seed due to chemical combination with condensed slag. A summary of the major conclusions in each of these areas is presented. A major output of the modeling effort has been the development of an MHD plasma chemistry core flow model. This model has been formulated into a computer program designated the PACKAGE code (Plasma Analysis, Chemical Kinetics, And Generator Efficiency). The PACKAGEmore » code is designed to calculate the effect of coal rank, ash percentage, ash composition, air preheat temperatures, equivalence ratio, and various generator channel parameters on the overall efficiency of open-cycle, coal-fired MHD generators. A complete description of the PACKAGE code and a preliminary version of the PACKAGE user's manual are included. A laboratory measurements program involving direct, mass spectrometric sampling of the positive and negative ions formed in a one atmosphere coal combustion plasma was also completed during the contract's initial phase. The relative ion concentrations formed in a plasma due to the methane augmented combustion of pulverized Montana Rosebud coal with potassium carbonate seed and preheated air are summarized. Positive ions measured include K/sup +/, KO/sup +/, Na/sup +/, Rb/sup +/, Cs/sup +/, and CsO/sup +/, while negative ions identified include PO/sub 3//sup -/, PO/sub 2//sup -/, BO/sub 2//sup -/, OH/sup -/, SH/sup -/, and probably HCrO/sub 3/, HMoO/sub 4//sup -/, and HWO/sub 3//sup -/. Comparison of the measurements with PACKAGE code predictions are presented. Preliminary design considerations for a mass spectrometric sampling probe capable of characterizing coal combustion plasmas from full scale combustors and flow trains are presented and discussed.« less

Stable CoT-1 repeat RNA is abundant and associated with euchromatic interphase chromosomes

PubMed Central

Hall, Lisa L.; Carone, Dawn M.; Gomez, Alvin; Kolpa, Heather J.; Byron, Meg; Mehta, Nitish; Fackelmayer, Frank O.; Lawrence, Jeanne B.

2014-01-01

SUMMARY Recent studies recognize a vast diversity of non-coding RNAs with largely unknown functions, but few have examined interspersed repeat sequences, which constitute almost half our genome. RNA hybridization in situ using CoT-1 (highly repeated) DNA probes detects surprisingly abundant euchromatin-associated RNA comprised predominantly of repeat sequences (“CoT-1 RNA”), including LINE-1. CoT-1-hybridizing RNA strictly localizes to the interphase chromosome territory in cis, and remains stably associated with the chromosome territory following prolonged transcriptional inhibition. The CoT-1 RNA territory resists mechanical disruption and fractionates with the non-chromatin scaffold, but can be experimentally released. Loss of repeat-rich, stable nuclear RNAs from euchromatin corresponds to aberrant chromatin distribution and condensation. CoT-1 RNA has several properties similar to XIST chromosomal RNA, but is excluded from chromatin condensed by XIST. These findings impact two “black boxes” of genome science: the poorly understood diversity of non-coding RNA and the unexplained abundance of repetitive elements. PMID:24581492

User's manual for the BNW-I optimization code for dry-cooled power plants. [AMCIRC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braun, D.J.; Daniel, D.J.; De Mier, W.V.

1977-01-01

This appendix provides a listing, called Program AMCIRC, of the BNW-1 optimization code for determining, for a particular size power plant, the optimum dry cooling tower design using ammonia flow in the heat exchanger tubes. The optimum design is determined by repeating the design of the cooling system over a range of design conditions in order to find the cooling system with the smallest incremental cost. This is accomplished by varying five parameters of the plant and cooling system over ranges of values. These parameters are varied systematically according to techniques that perform pattern and gradient searches. The dry coolingmore » system optimized by program AMCIRC is composed of a condenser/reboiler (condensation of steam and boiling of ammonia), piping system (transports ammonia vapor out and ammonia liquid from the dry cooling towers), and circular tower system (vertical one-pass heat exchangers situated in circular configurations with cocurrent ammonia flow in the tubes of the heat exchanger). (LCL)« less

The effect of condensation pressure on selected physical properties of mineral trioxide aggregate.

PubMed

Nekoofar, M H; Adusei, G; Sheykhrezae, M S; Hayes, S J; Bryant, S T; Dummer, P M H

2007-06-01

To examine the effect of condensation pressure on surface hardness, microstructure and compressive strength of mineral trioxide aggregate (MTA). White ProRoot MTA (Dentsply Tulsa Dental, Johnson City, TN, USA) was mixed and packed into cylindrical polycarbonate tubes. Six groups each of 10 specimens were subjected to pressures of 0.06, 0.44, 1.68, 3.22, 4.46 and 8.88 MPa respectively. The surface hardness of each specimen was measured using Vickers microhardness. Cylindrical specimens of 4 mm in diameter and 6 mm in height were prepared in polycarbonate cylindrical moulds for testing the compressive strength. Five groups of 10 specimens were prepared using pressures of 0.06, 0.44, 1.68, 3.22 or 4.46 MPa. Data were subjected to one-way anova. The microstructure was analysed using a scanning electron microscope (SEM) after sectioning specimens with a scalpel. A trend was observed for higher condensation pressures to produce lower surface hardness values. A condensation pressure of 8.88 MPa produced specimens with significantly lower values in terms of surface hardness than other groups (P<0.001). A condensation pressure of 1.68 MPa conferred the maximum compressive strength; however, it was not statistically different. Higher condensation pressures resulted in fewer voids and microchannels when analysed with SEM. In specimens prepared with lower condensation pressures distinctive crystalline structures were observed. They tended to appear around microchannels. Condensation pressure may affect the strength and hardness of MTA. Use of controlled condensation pressure in sample preparation for future studies is suggested.

Numerical Simulations of Laser-Driven Microflyer Plates

NASA Astrophysics Data System (ADS)

Colvin, Jeffrey D.; Frank, Alan M.; Lee, Ronald S.; Remington, Bruce A.

2000-10-01

Experiments conducted in the US and France have accelerated few-micron-thick foils of aluminum to velocities of 3 - 5 km/s using 25 - 50 J/cm^2 of 1-μm laser light (1,2). These microflyer plates are not too dissimilar in size and velocity from interplanetary dust particles (3). We are performing numerical simulations of these experiments with the 2-D radiation-hydrodynamics code LASNEX (4), incorporating a model for low-fluence electromagnetic wave reflection and absorption in metals, with the objective of determining the physical processes important to optimizing the flyer design. We will discuss our preliminary findings, including the efficacy of a thermal insulation layer and the role played by the substrate on which the flyer is mounted. (1) W.M. Trott, R.E. Setchell, and A.V. Farnsworth, Jr., in Shock Compression of Condensed Matter-1999, ed. M.D. Furnish, L.C. Chhabildas, and R.S. Hixson, AIP, 2000, pp. 1203-06. (2) J. L. Labaste, M. Doucet, and P. Joubert, in Shock Compression of Condensed Matter-1995, ed. S.C. Schmidt and W.C. Tao, AIP, 1996, pp. 1221-24. (3) W.W. Anderson and T.J. Ahrens, J. Geophys. Res. 99, 2063 (1994). (4) G. B. Zimmerman and W. L. Kruer, Comments Plasma Phys. Controlled Fusion 2, 51 (1975).

Numerical simulation code for self-gravitating Bose-Einstein condensates

NASA Astrophysics Data System (ADS)

Madarassy, Enikő J. M.; Toth, Viktor T.

2013-04-01

We completed the development of simulation code that is designed to study the behavior of a conjectured dark matter galactic halo that is in the form of a Bose-Einstein Condensate (BEC). The BEC is described by the Gross-Pitaevskii equation, which can be solved numerically using the Crank-Nicholson method. The gravitational potential, in turn, is described by Poisson’s equation, that can be solved using the relaxation method. Our code combines these two methods to study the time evolution of a self-gravitating BEC. The inefficiency of the relaxation method is balanced by the fact that in subsequent time iterations, previously computed values of the gravitational field serve as very good initial estimates. The code is robust (as evidenced by its stability on coarse grids) and efficient enough to simulate the evolution of a system over the course of 109 years using a finer (100×100×100) spatial grid, in less than a day of processor time on a contemporary desktop computer. Catalogue identifier: AEOR_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOR_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5248 No. of bytes in distributed program, including test data, etc.: 715402 Distribution format: tar.gz Programming language: C++ or FORTRAN. Computer: PCs or workstations. Operating system: Linux or Windows. Classification: 1.5. Nature of problem: Simulation of a self-gravitating Bose-Einstein condensate by simultaneous solution of the Gross-Pitaevskii and Poisson equations in three dimensions. Solution method: The Gross-Pitaevskii equation is solved numerically using the Crank-Nicholson method; Poisson’s equation is solved using the relaxation method. The time evolution of the system is governed by the Gross-Pitaevskii equation; the solution of Poisson’s equation at each time step is used as an initial estimate for the next time step, which dramatically increases the efficiency of the relaxation method. Running time: Depends on the chosen size of the problem. On a typical personal computer, a 100×100×100 grid can be solved with a time span of 10 Gyr in approx. a day of running time.

Draft Genome Sequence of a Novel Chitinophaga sp. Strain, MD30, Isolated from a Biofilm in an Air Conditioner Condensate Pipe

PubMed Central

Darris, Maxwell

2017-01-01

ABSTRACT Most of the 24 known Chitinophaga species were originally isolated from soils. We report the draft genome sequence of a putatively novel Chitinophaga sp. from a biofilm in an air conditioner condensate pipe. The genome comprises 7,661,303 bp in one scaffold, 5,694 predicted protein-coding sequences, and a G+C content of 47.6%. PMID:29051259

Non-equilibrium condensation of supercritical carbon dioxide in a converging-diverging nozzle

NASA Astrophysics Data System (ADS)

Ameli, Alireza; Afzalifar, Ali; Turunen-Saaresti, Teemu

2017-03-01

Carbon dioxide (CO2) is a promising alternative as a working fluid for future energy conversion and refrigeration cycles. CO2 has low global warming potential compared to refrigerants and supercritical CO2 Brayton cycle ought to have better efficiency than today’s counter parts. However, there are several issues concerning behaviour of supercritical CO2 in aforementioned applications. One of these issues arises due to non-equilibrium condensation of CO2 for some operating conditions in supercritical compressors. This paper investigates the non-equilibrium condensation of carbon dioxide in the course of an expansion from supercritical stagnation conditions in a converging-diverging nozzle. An external look-up table was implemented, using an in-house FORTRAN code, to calculate the fluid properties in supercritical, metastable and saturated regions. This look-up table is coupled with the flow solver and the non-equilibrium condensation model is introduced to the solver using user defined expressions. Numerical results are compared with the experimental measurements. In agreement with the experiment, the distribution of Mach number in the nozzle shows that the flow becomes supersonic in upstream region near the throat where speed of sound is minimum also the equilibrium reestablishment occurs at the outlet boundary condition.

A sensitivity study of the effects of evaporation/condensation accommodation coefficients on transient heat pipe modeling

NASA Astrophysics Data System (ADS)

Hall, Michael L.; Doster, J. Michael

1990-03-01

The dynamic behavior of liquid metal heat pipe models is strongly influenced by the choice of evaporation and condensation modeling techniques. Classic kinetic theory descriptions of the evaporation and condensation processes are often inadequate for real situations; empirical accommodation coefficients are commonly utilized to reflect nonideal mass transfer rates. The complex geometries and flow fields found in proposed heat pipe systems cause considerable deviation from the classical models. the THROHPUT code, which has been described in previous works, was developed to model transient liquid metal heat pipe behavior from frozen startup conditions to steady state full power operation. It is used here to evaluate the sensitivity of transient liquid metal heat pipe models to the choice of evaporation and condensation accommodation coefficients. Comparisons are made with experimental liquid metal heat pipe data. It is found that heat pipe behavior can be predicted with the proper choice of the accommodation coefficients. However, the common assumption of spatially constant accommodation coefficients is found to be a limiting factor in the model.

High Temperature Ultrasonic Transducers : Material Selection and Testing

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Bruno, Alessandro

2012-01-01

The task of my two-months internship was to test different materials to be used to build an high temperature transducer, to develop some prototypes and to test their performance, to assess the reliability of commercial product rated for such a temperature, as well as to collaborate in developing the signal processing code to measure the condensed water levels.

Assessment of MELCOR condensation models with the presence of noncondensable gas in natural convection flow regime

DOE PAGES

Yoon, Dhongik S; Jo, HangJin; Corradini, Michael L

2017-04-01

Condensation of steam vapor is an important mode of energy removal from the reactor containment. The presence of noncondensable gas complicates the process and makes it difficult to model. MELCOR, one of the more widely used system codes for containment analyses, uses the heat and mass transfer analogy to model condensation heat transfer. To investigate previously reported nodalization-dependence in natural convection flow regime, MELCOR condensation model as well as other models are studied. The nodalization-dependence issue is resolved by using physical length from the actual geometry rather than node size of each control volume as the characteristic length scale formore » MELCOR containment analyses. At the transition to turbulent natural convection regime, the McAdams correlation for convective heat transfer produces a better prediction compared to the original MELCOR model. The McAdams correlation is implemented in MELCOR and the prediction is validated against a set of experiments on a scaled AP600 containment. The MELCOR with our implemented model produces improved predictions. For steam molar fractions in the gas mixture greater than about 0.58, the predictions are within the uncertainty margin of the measurements. The simulation results still underestimate the heat transfer from the gas-steam mixture, implying that conservative predictions are provided.« less

Assessment of MELCOR condensation models with the presence of noncondensable gas in natural convection flow regime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Dhongik S; Jo, HangJin; Corradini, Michael L

Condensation of steam vapor is an important mode of energy removal from the reactor containment. The presence of noncondensable gas complicates the process and makes it difficult to model. MELCOR, one of the more widely used system codes for containment analyses, uses the heat and mass transfer analogy to model condensation heat transfer. To investigate previously reported nodalization-dependence in natural convection flow regime, MELCOR condensation model as well as other models are studied. The nodalization-dependence issue is resolved by using physical length from the actual geometry rather than node size of each control volume as the characteristic length scale formore » MELCOR containment analyses. At the transition to turbulent natural convection regime, the McAdams correlation for convective heat transfer produces a better prediction compared to the original MELCOR model. The McAdams correlation is implemented in MELCOR and the prediction is validated against a set of experiments on a scaled AP600 containment. The MELCOR with our implemented model produces improved predictions. For steam molar fractions in the gas mixture greater than about 0.58, the predictions are within the uncertainty margin of the measurements. The simulation results still underestimate the heat transfer from the gas-steam mixture, implying that conservative predictions are provided.« less

Draft Genome Sequence of a Novel Chitinophaga sp. Strain, MD30, Isolated from a Biofilm in an Air Conditioner Condensate Pipe.

PubMed

Wan, Xuehua; Darris, Maxwell; Hou, Shaobin; Donachie, Stuart P

2017-10-19

Most of the 24 known Chitinophaga species were originally isolated from soils. We report the draft genome sequence of a putatively novel Chitinophaga sp. from a biofilm in an air conditioner condensate pipe. The genome comprises 7,661,303 bp in one scaffold, 5,694 predicted protein-coding sequences, and a G+C content of 47.6%. Copyright © 2017 Wan et al.

DCA_Tools

DOE Office of Scientific and Technical Information (OSTI.GOV)

Summers, Michael S

2017-11-08

HPC software for ab-initio, condensed-matter physics, quantum mechanics calculations needs to be built on top of well tested libraries some of which address requirements unique to the programming domain. During the development of the DCA++ code, that we use in our research, we have developed a collection of libraries that may be of use to other computational scientists working in the same or similar domains. The libraries include: a) a pythonic input-language system, b) tensors whose shape is constructed from generalized dimension objects such at time domains. frequency domains, momentum domains, vertex domains et. al. and c) linear algebra operationsmore » that resolve to BLA/LAPACK operations when possible. This supports the implementation of Greens functions and operations on them such as are used in condensed matter physics.« less

Numerical Simulation of the Detonation of Condensed Explosives

NASA Astrophysics Data System (ADS)

Wang, Cheng; Ye, Ting; Ning, Jianguo

Detonation process of a condensed explosive was simulated using a finite difference method. Euler equations were applied to describe the detonation flow field, an ignition and growth model for the chemical reaction and Jones-Wilkins-Lee (JWL) equations of state for the state of explosives and detonation products. Based on the simple mixture rule that assumes the reacting explosives to be a mixture of the reactant and product components, 1D and 2D codes were developed to simulate the detonation process of high explosive PBX9404. The numerical results are in good agreement with the experimental results, which demonstrates that the finite difference method, mixture rule and chemical reaction proposed in this paper are adequate and feasible.

Modeling of Kerena Emergency Condenser

NASA Astrophysics Data System (ADS)

Bryk, Rafał; Schmidt, Holger; Mull, Thomas; Wagner, Thomas; Ganzmann, Ingo; Herbst, Oliver

2017-12-01

KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA) was built in Karlstein, Germany. The emergency condenser (EC) system transfers heat from the reactor pressure vessel (RPV) to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA). The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

Integral Reactor Containment Condensation Model and Experimental Validation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Qiao; Corradini, Michael

This NEUP funded project, NEUP 12-3630, is for experimental, numerical and analytical studies on high-pressure steam condensation phenomena in a steel containment vessel connected to a water cooling tank, carried out at Oregon State University (OrSU) and the University of Wisconsin at Madison (UW-Madison). In the three years of investigation duration, following the original proposal, the planned tasks have been completed: (1) Performed a scaling study for the full pressure test facility applicable to the reference design for the condensation heat transfer process during design basis accidents (DBAs), modified the existing test facility to route the steady-state secondary steam flowmore » into the high pressure containment for controllable condensation tests, and extended the operations at negative gage pressure conditions (OrSU). (2) Conducted a series of DBA and quasi-steady experiments using the full pressure test facility to provide a reliable high pressure condensation database (OrSU). (3) Analyzed experimental data and evaluated condensation model for the experimental conditions, and predicted the prototypic containment performance under accidental conditions (UW-Madison). A film flow model was developed for the scaling analysis, and the results suggest that the 1/3 scaled test facility covers large portion of laminar film flow, leading to a lower average heat transfer coefficient comparing to the prototypic value. Although it is conservative in reactor safety analysis, the significant reduction of heat transfer coefficient (50%) could under estimate the prototypic condensation heat transfer rate, resulting in inaccurate prediction of the decay heat removal capability. Further investigation is thus needed to quantify the scaling distortion for safety analysis code validation. Experimental investigations were performed in the existing MASLWR test facility at OrST with minor modifications. A total of 13 containment condensation tests were conducted for pressure ranging from 4 to 21 bar with three different static inventories of non-condensable gas. Condensation and heat transfer rates were evaluated employing several methods, notably from measured temperature gradients in the HTP as well as measured condensate formation rates. A detailed mass and energy accounting was used to assess the various measurement methods and to support simplifying assumptions required for the analysis. Condensation heat fluxes and heat transfer coefficients are calculated and presented as a function of pressure to satisfy the objectives of this investigation. The major conclusions for those tests are summarized below: (1) In the steam blow-down tests, the initial condensation heat transfer process involves the heating-up of the containment heat transfer plate. An inverse heat conduction model was developed to capture the rapid transient transfer characteristics, and the analysis method is applicable to SMR safety analysis. (2) The average condensation heat transfer coefficients for different pressure conditions and non-condensable gas mass fractions were obtained from the integral test facility, through the measurements of the heat conduction rate across the containment heat transfer plate, and from the water condensation rates measurement based on the total energy balance equation. 15 (3) The test results using the measured HTP wall temperatures are considerably lower than popular condensation models would predict mainly due to the side wall conduction effects in the existing MASLWR integral test facility. The data revealed the detailed heat transfer characteristics of the model containment, important to the SMR safety analysis and the validation of associated evaluation model. However this approach, unlike separate effect tests, cannot isolate the condensation heat transfer coefficient over the containment wall, and therefore is not suitable for the assessment of the condensation heat transfer coefficient against system pressure and noncondensable gas mass fraction. (4) The average condensation heat transfer coefficients measured from the water condensation rates through energy balance analysis are appropriate, however, with considerable uncertainties due to the heat loss and temperature distribution on the containment wall. With the consideration of the side wall conduction effects, the results indicate that the measured heat transfer coefficients in the tests is about 20% lower than the prediction of Dehbi’s correlation, mainly due to the side wall conduction effects. The investigation also indicates an increase in the condensation heat transfer coefficient at high containment pressure conditions, but the uncertainties invoked with this method appear to be substantial. (5) Non-condensable gas in the tests has little effects on the condensation heat transfer at high elevation measurement ports. It does affect the bottom measurements near the water level position. The results suggest that the heavier non-condensable gas is accumulated in the lower portion of the containment due to stratification in the narrow containment space. The overall effects of the non-condensable gas on the heat transfer process should thus be negligible for tall containments of narrow condensation spaces in most SMR designs. Therefore, the previous correlations with noncondensable gas effects are not appropriate to those small SMR containments due to the very poor mixing of steam and non-condensable gas. The MELCOR simulation results agree with the experimental data reasonably well. However, it is observed that the MELCOR overpredicts the heat flux for all analyzed tests. The MELCOR predicts that the heat fluxes for CCT’s approximately range from 30 to 45 kW/m2 whereas the experimental data (averaged) ranges from about 25 to 40 kW/m2. This may be due to the limited availability of liquid film models included in MELCOR. Also, it is believed that due to complex test geometry, measured temperature gradients across the heat transfer plate may have been underestimated and thus the heat flux had been underestimated. The MELCOR model predicts a film thickness on the order of 100 microns, which agrees very well with film flow model developed in this study for scaling analysis. However, the expected differences in film thicknesses for near vacuum and near atmospheric test conditions are not significant. Further study on the behavior of condensate film is expected to refine the simulation results. Possible refinements include but are not limited to, the followings: CFD simulation focusing on the liquid film behavior and benchmarking with experimental analyses for simpler geometries. 16 1 INTRODUCTION This NEUP funded project, NEUP 12-3630, is for experimental, numerical and analytical studies on high-pressure steam condensation phenomena in a steel containment vessel connected to a water cooling tank, carried out at Oregon State University (OrSU) and the University of Wisconsin at Madison (UW-Madison). The experimental results are employed to validate the containment condensation model in reactor containment system safety analysis code for integral SMRs. Such a containment condensation model is important to demonstrate the adequate cooling. In the three years of investigation, following the original proposal, the following planned tasks have been completed: (1) Performed a scaling study for the full pressure test facility applicable to the reference design for the condensation heat transfer process during design basis accidents (DBAs), modified the existing test facility to route the steady-state secondary steam flow into the high pressure containment for controllable condensation tests, and extended the operations at negative gage pressure conditions (OrSU). (2) Conducted a series of DBA and quasi-steady experiments using the full pressure test facility to provide a reliable high pressure condensation database (OrSU). (3) Analyzed experimental data and evaluated condensation model for the experimental conditions, and predicted the prototypic containment performance under accidental conditions (UW-Madison). The results are applicable to integral Small Modular Reactor (SMR) designs, including NuScale, mPower, Westinghouse SMR, Holtec-160 and other integral reactors with small containments of relatively high pressures under accidental conditions. Testing has been conducted at the OrSU laboratory in the existing MASLWR (Multi-Application Small Light Water Reactor) integral test facility sponsored by the US Department of Energy. Its highpressure stainless steel containment model (~2 MPa) is scaled to the NuScale SMR currently under development at NuScale Power, Inc.. Minor modifications to the model containment have been made to control the non-condensable gas fraction and to utilize the secondary loop stable steam flow for condensation testing. UW-Madison has developed a containment condensation model, which leveraged previous validated containment heat transfer work carried out at UW-Madison, and extended the range of applicability of the model to integral SMR designs that utilize containment vessels of high heat transfer efficiencies. In this final report, the research background and literature survey are presented in Chapter 2 and 3, respectively. The test facility description and modifications are summarized in Chapter 4, and the scaling analysis is introduced in Chapter 5. The tests description, procedures, and data analysis are presented in Chapter 6, while the numerical modeling is presented in Chapter 7, followed by a conclusion section in Chapter 8.« less

An Evaluation of Liquid and Two-Phase Cooling Techniques for Use in Electrical Machinery.

DTIC Science & Technology

1984-12-01

equations (3.5) & (3.6) k Thermal conductivity L Condenser length m Mass flow rate b Nu Nusselt number P Pressure Pr Prandtl number Q Heat-transfer rate...IRI finned condenser (with axially-straight or helical fins), or 4. use an internally-grooved condenser . Marto [17] presents a detailed discussion of...the appropriate models for the first two cases. For example, for rotating truncated-cone condensers , Ballback [28] performed a Nusselt -type analysis

NASA Lewis steady-state heat pipe code users manual

NASA Technical Reports Server (NTRS)

Tower, Leonard K.; Baker, Karl W.; Marks, Timothy S.

1992-01-01

The NASA Lewis heat pipe code was developed to predict the performance of heat pipes in the steady state. The code can be used as a design tool on a personal computer or with a suitable calling routine, as a subroutine for a mainframe radiator code. A variety of wick structures, including a user input option, can be used. Heat pipes with multiple evaporators, condensers, and adiabatic sections in series and with wick structures that differ among sections can be modeled. Several working fluids can be chosen, including potassium, sodium, and lithium, for which monomer-dimer equilibrium is considered. The code incorporates a vapor flow algorithm that treats compressibility and axially varying heat input. This code facilitates the determination of heat pipe operating temperatures and heat pipe limits that may be encountered at the specified heat input and environment temperature. Data are input to the computer through a user-interactive input subroutine. Output, such as liquid and vapor pressures and temperatures, is printed at equally spaced axial positions along the pipe as determined by the user.

NASA Lewis steady-state heat pipe code users manual

NASA Astrophysics Data System (ADS)

Tower, Leonard K.; Baker, Karl W.; Marks, Timothy S.

1992-06-01

The NASA Lewis heat pipe code was developed to predict the performance of heat pipes in the steady state. The code can be used as a design tool on a personal computer or with a suitable calling routine, as a subroutine for a mainframe radiator code. A variety of wick structures, including a user input option, can be used. Heat pipes with multiple evaporators, condensers, and adiabatic sections in series and with wick structures that differ among sections can be modeled. Several working fluids can be chosen, including potassium, sodium, and lithium, for which monomer-dimer equilibrium is considered. The code incorporates a vapor flow algorithm that treats compressibility and axially varying heat input. This code facilitates the determination of heat pipe operating temperatures and heat pipe limits that may be encountered at the specified heat input and environment temperature. Data are input to the computer through a user-interactive input subroutine. Output, such as liquid and vapor pressures and temperatures, is printed at equally spaced axial positions along the pipe as determined by the user.

TRAC-PF1/MOD1 support calculations for the MIST/OTIS program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujita, R.K.; Knight, T.D.

1984-01-01

We are using the Transient Reactor Analysis Code (TRAC), specifically version TRAC-PF1/MOD1, to perform analyses in support of the MultiLoop Integral-System Test (MIST) and the Once-Through Integral-System (OTIS) experiment program. We have analyzed Geradrohr Dampferzeuger Anlage (GERDA) Test 1605AA to benchmark the TRAC-PF1/MOD1 code against phenomena expected to occur in a raised-loop B and W plant during a small-break loss-of-coolant accident (SBLOCA). These results show that the code can calculate both single- and two-phase natural circulation, flow interruption, boiler-condenser-mode (BCM) heat transfer, and primary-system refill in a B and W-type geometry with low-elevation auxiliary feedwater. 19 figures, 7 tables.

Quantum Turbulence ---Another da Vinci Code---

NASA Astrophysics Data System (ADS)

Tsubota, M.

Quantum turbulence comprises a tangle of quantized vorticeswhich are stable topological defects created by Bose-Einstein condensation, being realized in superfluid helium and atomic Bose-Einstein condensates. In recent years there has been a growing interest in quantum turbulence. One of the important motivations is to understand the relation between quantum and classical turbulence. Quantum turbulence is expected to be much simpler than usual classical turbulence and give a prototype of turbulence. This article reviews shortly the recent research developments on quantum turbulence.

[Literary, biographic and autoethnographic contributions in Spanish medical anthropology: the case of Catalonia].

PubMed

Alegre-Agís, Elisa; Riccò, Isabella

2017-01-01

The autoethnographic method has been an important contribution to the development of medical anthropology in Spain. This article first reviews and explores documents published before 1980 that are usually classified as literature and autobiography and are linked to the health-disease-care process, a paradigmatic example of which is Ramona Via's diary Com neixen els Catalans [How Catalans are born] published in 1972. The second part of the article is focused on contributions carried out since the 1980s using the concept of autoethnography, which have as their object the body, health and illness based on a subjective ethnographic experience. This period, unlike the first, is characterized by the emergence of anthropologist authors who have promoted the development of this method, legitimized by the Tarragona School and substantialized in the first Spanish conference of autoethnography in 2015.

A NOVEL HIGH-SPEED METHOD FOR THE GENERATION OF 4-ARYLDIHYDROPYRIMIDINE COMPOUND LIBRARIES USING A MICROWAVE-ASSISTED BIGINELLI CONDENSATION PROTOCOL -

EPA Science Inventory

In this presentation we report the application of microwave assisted chemistry to the parallel synthesis of 4-aryl-3,4-dihydropyrimidin-2(1H)-ones employing a solventless Biginelli multicomponent condensation protocol. The novel method employs neat mixtures of B-ketoesters, aryl ...

Regenerable biocide delivery unit, volume 2

NASA Technical Reports Server (NTRS)

Atwater, James E.; Wheeler, Richard R., Jr.

1992-01-01

Source code for programs dealing with the following topics are presented: (1) life cycle test stand-parametric test stand control (in BASIC); (2) simultaneous aqueous iodine equilibria-true equilibrium (in C); (3) simultaneous aqueous iodine equilibria-pseudo-equilibrium (in C); (4) pseudo-(fast)-equilibrium with iodide initially present (in C); (5) solution of simultaneous iodine rate expressions (Mathematica); (6) 2nd order kinetics of I2-formic acid in humidity condensate (Mathematica); (7) prototype RMCV onboard microcontroller (CAMBASIC); (8) prototype RAM data dump to PC (in BASIC); and (9) prototype real time data transfer to PC (in BASIC).

Characterization of 1:1 Random Copolymers Obtained from 6-, 7-, 11-, and 12-Carbon Amino Acids.

DTIC Science & Technology

1993-10-22

Random Copolymers Obtained From 6-, 7-, 11-, and 12-Carbon Amino Acids by C. G. Johnson and L. J. Mathias 0 T .... Prepared for Publication r. t in the...NOOOG4-f-j- From 6-, 7-, 11-, and 12-Carbon Amino Acids 1225 ~~~ :: V Co~de 413m(iUK C. G Johnson, and Lo J. Mathias ś RFORMING ORGANIZA7,iCN ;fAMjjS...distribution is unlimited. Copolymers were prepared from the title amino acids by rr ilt condensation under dry nitrogen. The resulting copolymers were

Large Scale Gas Mixing and Stratification Triggered by a Buoyant Plume With and Without Occurrence of Condensation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paladino, Domenico; Auban, Olivier; Zboray, Robert

The benefits of using codes with 3-D capabilities to address safety issues of LWRs will be applicable to both the current generation of nuclear reactors as well to future ALWRs. The phenomena governing the containment response in case of some postulated severe accident scenarios include gas (air, hydrogen, steam) stratification in the containment, gas distribution between containment compartments, wall condensation, etc. These phenomena are driven by buoyant high momentum injection (jets) and/or low momentum injection (plumes). For instance, mixing in the immediate vicinity of the postulated line break is mainly dominated by very high velocity efflux, while low-momentum flows aremore » responsible for most of the transport processes within the containment. A project named SETH is currently in progress under the auspices of 15 OECD countries, with the aim of creating an experimental database suitable to assess the 3-D code capabilities in analyzing key-physical phenomena relevant for LWR safety analysis. This paper describes some results of two SETH tests, performed in the PANDA facility (located at PSI in Switzerland), focusing on plumes flowing near a containment wall. The plumes are generated by injecting a constant amount of steam in one of two interconnected vessels initially filled with air. In one of the two tests the temperature of the injected steam and the initial containment wall and fluid temperatures allowed for condensation during the test. (authors)« less

The ZONMET thermodynamic and kinetic model of metal condensation

NASA Astrophysics Data System (ADS)

Petaev, Michail I.; Wood, John A.; Meibom, Anders; Krot, Alexander N.; Keil, Klaus

2003-05-01

The ZONMET model of metal condensation is a FORTRAN computer code that calculates condensation with partial isolation-type equilibrium partitioning of the 19 most abundant elements among 203 gaseous and 488 condensed phases and growth in the nebula of a zoned metal grain by condensation from the nebular gas accompanied by diffusional redistribution of Ni, Co, and Cr. Of five input parameters of the ZONMET model (chemical composition of the system expressed as the dust/gas [ D/ G] ratio, nebular pressure [ Ptot], isolation degree [ξ], cooling rate ( CR), and seed size), only two—the D/ G ratio and the CR of the nebular source region of a zoned Fe,Ni grain—are important in determining the grain radius and Ni, Co, and Cr zoning profiles. We found no evidence for the supercooling during condensation of Fe,Ni metal that is predicted by the homogeneous nucleation theory. The model allows estimates to be made of physicochemical parameters in the CH chondrite nebular source regions. Modeling growth and simultaneous diffusional redistribution of Ni, Co, and Cr in the zoned metal grains of CH chondrites reveals that the condensation zoning profiles were substantially modified by diffusion while the grains were growing in the nebula. This means that previous estimates of the physicochemical conditions in the nebular source regions of CH and CB chondrites, based on measured zoning profiles of Ni, Co, Cr, and platinum group elements in Fe,Ni metal grains, need to be corrected. The two zoned metal grains in the PAT 91456 and NWA 470 CH chondrites studied so far require nebular source regions with different chemical compositions ( D/ G = 1 and D/ G = 4, respectively) and thermal histories characterized by variable cooling rates ( CR = 0.011 + 0.0022 × Δ T K/h and CR = 0.05 + 0.0035 × Δ T K/h, respectively). It appears that the metal grains of the CH chondrites were formed in multiple nebular source regions or in different events within the same source region as the CB chondrite metal grains were formed.

Condenser: a statistical aggregation tool for multi-sample quantitative proteomic data from Matrix Science Mascot Distiller™.

PubMed

Knudsen, Anders Dahl; Bennike, Tue; Kjeldal, Henrik; Birkelund, Svend; Otzen, Daniel Erik; Stensballe, Allan

2014-05-30

We describe Condenser, a freely available, comprehensive open-source tool for merging multidimensional quantitative proteomics data from the Matrix Science Mascot Distiller Quantitation Toolbox into a common format ready for subsequent bioinformatic analysis. A number of different relative quantitation technologies, such as metabolic (15)N and amino acid stable isotope incorporation, label-free and chemical-label quantitation are supported. The program features multiple options for curative filtering of the quantified peptides, allowing the user to choose data quality thresholds appropriate for the current dataset, and ensure the quality of the calculated relative protein abundances. Condenser also features optional global normalization, peptide outlier removal, multiple testing and calculation of t-test statistics for highlighting and evaluating proteins with significantly altered relative protein abundances. Condenser provides an attractive addition to the gold-standard quantitative workflow of Mascot Distiller, allowing easy handling of larger multi-dimensional experiments. Source code, binaries, test data set and documentation are available at http://condenser.googlecode.com/. Copyright © 2014 Elsevier B.V. All rights reserved.

Space Technology Industry Forum

NASA Image and Video Library

2010-07-13

Bobby Braun, far left, NASA Chief Technologist, speaks during the NASA New Space Technology Industry Forum being held at the University of Maryland in College Park on Wednesday, July 14, 2010. Mr. Braun is joined on the panel by James Reuther, Director of Strategic Integration at NASA Headquarters, second from left; Keith Belvin, NASA Systems Engineer at NASA Langley Research Center and Ramona Travis, NASA Stennis Space Center Chief Technologist, far right. During the two-day event, speakers are focusing on the president's fiscal year 2011 budget request for NASA's new Space Technology Program. Representatives from industry, academia and the federal government are in attendance to discuss strategy, development and implementation of NASA's proposed new technology-enabled exploration. Photo Credit: (NASA/Carla Cioffi)

Effect of introducing legumes containing condensed tannins in an orchardgrass diet on forage nutritive value and enteric methane output in continuous culture

USDA-ARS?s Scientific Manuscript database

Legumes containing condensed tannins (CT) have been shown to reduce enteric CH4 in ruminants; however, research is lacking on how increased CT levels affect forage nutritive value and CH4 output. A 4-unit, dual-flow continuous culture fermentor system was used to assess CH4 output of CT legumes in a...

Influence of condensing equipment and temperature on exhaled breath condensate pH, total protein and leukotriene concentrations.

PubMed

Czebe, Krisztina; Barta, Imre; Antus, Balázs; Valyon, Márta; Horváth, Ildikó; Kullmann, Tamás

2008-05-01

Exhaled breath condensate analysis is an attractive but still not fully standardised method for investigating airway pathology. Adherence of biomarkers to various condensing surfaces and changes in condensing temperature has been considered to be responsible for the variability of the results. Our aims were to compare the efficacy of different types of condensers and to test the influence of condensing temperature on condensate composition. Breath condensates from 12 healthy persons were collected in two settings: (1) by using three condensers of different type (EcoScreen, R-Tube, Anacon) and (2) by using R-Tube condenser either cooled to -20 or -70 degrees C. Condensate pH at standardised CO(2) level was determined; protein content was measured by the Bradford method and leukotrienes by EIA. Breath condensates collected using EcoScreen were more alkaline (6.45+/-0.20 vs. 6.19+/-0.23, p<0.05 and 6.10+/-0.26, p<0.001) and contained more protein (3.89+/-2.03 vs. 2.65+/-1.98, n.s. and 1.88+/-1.99 microg/ml, p<0.004) as compared to the other devices. Only parameters obtained with R-Tube and Anacon correlated. Condensing temperature affected condensate pH (5.99+/-0.20 at -20 degrees C and 5.82+/-0.07 at -70 degrees C, p<0.05) but not protein content. Leukotriene B(4) was not found in any sample and cysteinyl-leukotriene was not found in condensates collected with R-Tube or Anacon. Condenser type influences sample pH, total protein content and cysteinyl-leukotriene concentration. Condensing temperature influences condensate pH but not total protein content. These results suggest that adherence of the biomarkers to condenser surface and condensing temperature may play a role but does not fully explain the variability of EBC biomarker levels.

Solution of the neutronics code dynamic benchmark by finite element method

NASA Astrophysics Data System (ADS)

Avvakumov, A. V.; Vabishchevich, P. N.; Vasilev, A. O.; Strizhov, V. F.

2016-10-01

The objective is to analyze the dynamic benchmark developed by Atomic Energy Research for the verification of best-estimate neutronics codes. The benchmark scenario includes asymmetrical ejection of a control rod in a water-type hexagonal reactor at hot zero power. A simple Doppler feedback mechanism assuming adiabatic fuel temperature heating is proposed. The finite element method on triangular calculation grids is used to solve the three-dimensional neutron kinetics problem. The software has been developed using the engineering and scientific calculation library FEniCS. The matrix spectral problem is solved using the scalable and flexible toolkit SLEPc. The solution accuracy of the dynamic benchmark is analyzed by condensing calculation grid and varying degree of finite elements.

Modeling fission product vapor transport in the Falcon facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shepherd, I.M.; Drossinos, Y.; Benson, C.G.

1995-05-01

An extensive database of aerosol Experiments exists and has been used for checking aerosol transport codes. Data for fission product vapor transport are harder to find. Some qualitative data are available, but the Falcon thermal gradient tube tests carried out at AEA Technology`s laboratories in Winfrith, England, mark the first serious attempt to provide a set of experiments suitable for the validation of codes that predict the transport and condensation of realistic mixtures of fission product vapors. Four of these have been analyzed to check how well the computer code VICTORIA can predict the most important phenomena. Of the fourmore » experiments studied, two are reference cases (FAL-17 and FAL-19), one is a case without boric acid (FAL-18), and the other is run in a reducing atmosphere (FAL-20). The results show that once the vapors condense onto aerosols, VICTORIA can predict their deposition rather well. The dominant mechanism is thermophoresis, and each element deposits with more or less the same deposition velocity. The behavior of the vapors is harder to interpret. Essentially, it is important to know the temperature at which each element condenses. It is clear from the measurements that this temperature changed from test to test-caused mostly by the different speciation as the composition of the carrier gas and the relative concentration of other fission products changed. Only in the test with a steam atmosphere and without boric acid was the assumption valid that most of the iodine is cesium iodide and most of the cesium is cesium hydroxide. In general, VICTORIA predicts that, with the exception of cesium, there will be less variation in the speciation-and, hence, variation in the deposition-between tests than is in fact observed. VICTORIA underpredicts the volatility of most elements, and this is partly a consequence of the ideal solution assumption and partly an overestimation of vapor/aerosol interactions.« less

Frustration in Condensed Matter and Protein Folding

NASA Astrophysics Data System (ADS)

Lorelli, S.; Cabot, A.; Sundarprasad, N.; Boekema, C.

Using computer modeling we study frustration in condensed matter and protein folding. Frustration is due to random and/or competing interactions. One definition of frustration is the sum of squares of the differences between actual and expected distances between characters. If this sum is non-zero, then the system is said to have frustration. A simulation tracks the movement of characters to lower their frustration. Our research is conducted on frustration as a function of temperature using a logarithmic scale. At absolute zero, the relaxation for frustration is a power function for randomly assigned patterns or an exponential function for regular patterns like Thomson figures. These findings have implications for protein folding; we attempt to apply our frustration modeling to protein folding and dynamics. We use coding in Python to simulate different ways a protein can fold. An algorithm is being developed to find the lowest frustration (and thus energy) states possible. Research supported by SJSU & AFC.

The application of condensate water as an additional cooling media intermittently in condenser of a split air conditioning

NASA Astrophysics Data System (ADS)

Ardita, I. N.; Subagia, I. W. A.

2018-01-01

The condensate water produced by indoor a split air conditioning is usually not utilized and thrown away into the environment. The result of measurement shows that the temperature of condensate water produced by split air conditioning is quite low, that is 19-22 °C at the rate of 16-20 mL / min and it has PH balance. Under such conditions, Air Condensate produced by split air conditioning should still be recovered as an additional cooling medium on the condenser. This research will re-investigate the use of condensate water as an intermittent additional cooling of the condenser to increase the cooling capacity and performance of the air conditioning system. This research is done by experimental method whose implementation includes; designing and manufacturing of experimental equipment, mounting measuring tools, experimental data retrieval, data processing and yield analysis. The experimental results show that the use of condensate water as an intermittent additional cooling medium on split air conditioning condenser can increase the refrigeration effect about 2%, cooling capacity about 4% and 7% of COP system. Experimental results also show a decrease in power consumption in the system compressor about 3%

One-Step Condensation and Hydrogenation of Furfural-Acetone Using Mixed and Single Catalyst Based on Ni/M-Oxide [M=Al; Mg

NASA Astrophysics Data System (ADS)

Ulfa, S. M.; Pramesti, I. N.; Mustafidah, H.

2018-01-01

Modification of furfural by condensation and hydrogenation reaction is a promising approach to produce higher alkane derivatives (C8-C13) as diesel fraction. This research investigated the catalytic activity of Ni/MgO as bifunctional catalyst compared with MgO-Ni/Al2O3 mixed catalyst for condensation-hydrogenation reaction. The Ni/MgO and Ni/Al2O3 with 20% Ni loading were prepared by wet impregnation methods using Ni(NO3)2.6H2O salt, calcined and reduced at 500°C. The catalyst performance was tested for one-step condensation-hydrogenation reaction using autoclave oil batch reactor. The reaction was conducted by reacting furfural and acetone in 1:1 ratio using water as solvent. Condensation reaction was performed at 100°C for 8 hours, followed by hydrogenation at 120°C during 7 hours. Analysis by gas chromatography showed that C=C double bond of furfurylidene acetone were successfully hydrogenated. Using Ni/MgO catalyst at 120°C, the products were identified as 1,5-bis-(2-furanyl)-1,4-penta-1-ene-3-one (2.68%) and 1,5-bis-(2-furanyl)-1,4-pentan-3-one (trace amount). On the other hand, reaction using mixed catalyst, MgO-Ni/Al2O3 showed better activity over bifunctional Ni/MgO at the same reaction temperature. The products were identified as 4-(2-furanyl)-3-butan-2-one (27.30%); 1,5-bis-(2-furanyl)-1,4-penta-1-ene-3-one (3.82%) and 1,5-bis-(2-furanyl)-1,4-pentan-3-one (1.11%). The impregnation of Ni on MgO decrease the physical properties of catalyst, confirmed by surface area analysis (SAA).

Fast production of Bose-Einstein condensates of metastable helium

NASA Astrophysics Data System (ADS)

Bouton, Q.; Chang, R.; Hoendervanger, A. L.; Nogrette, F.; Aspect, A.; Westbrook, C. I.; Clément, D.

2015-06-01

We report on the Bose-Einstein condensation of metastable 4He atoms using a hybrid approach, consisting of a magnetic quadrupole and an optical dipole trap. In our setup we cross the phase transition with 2 ×106 atoms, and we obtain pure condensates of 5 ×105 atoms in the optical trap. This approach to cooling 4He provides enhanced cycle stability, large optical access to the atoms and results in the production of a condensate every 6 s—a factor 2 faster than the state of the art. This speed-up will significantly reduce the data acquisition time needed for the measurement of many particle correlations, made possible by the ability of metastable helium atoms to be detected individually.

Synthesis of oxazolidine-2,4-diones by a tandem phosphorus-mediated carboxylative condensation-cyclization reaction using atmospheric carbon dioxide.

PubMed

Zhang, Wen-Zhen; Xia, Tian; Yang, Xu-Tong; Lu, Xiao-Bing

2015-04-11

The oxazolidine-2,4-dione motif is found frequently in biologically important compounds. A tandem phosphorus-mediated carboxylative condensation of primary amines and α-ketoesters/base-catalyzed cyclization reaction have been developed. These processes provide a novel and convenient access to various oxazolidine-2,4-diones in a one-pot fashion using atmospheric carbon dioxide and readily available substrates under very mild and transition-metal-free conditions.

Radiation hardening of low condensation products containing amino group (in Japanese)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okamura, S.; Hayashi, K.; Kaetsu, I.

1967-11-01

An initial condensation product is prepared by condensing a monomer selected from the group of urea, thiourea, melanine, aniline and acidamide with formalin. 0ne or more of the initial condensation product is then mixed with a substance which forms an acid or base by irradiation with an ionizing radiation in the presence or absence of the initial condensation product, except for halogenated hydrocarbon. The mixture is hardened by irradiation of the ionizing radiation to form a resinous substance. Formamide, acetamide, oxalic diamide, succinic diamide, acrylamide, etc. can be used as the acidamide monomer. Phosphonitrile chloride, cyanuric chloride, chloral hydrate, trichloroaceticmore » acid, monochloroacetic acid, ammonium chloride, aluminium chloride, gaseous chlorine, sullurous acid gas, sodium sulfite, aluminium sulfate, potassium hydrogensulfate, sodium pyrophosphate, potassium pyrophosphate, potassium phosphate, ammonia, bromine, bromal, bromal hydrate, dibromoacetic acid, sulfonated benzene, sulfonated toluene, etc. can be used as the acid- or base- forming substance. To the initial condensation product may be added 0.5-20%, in certain cases 20-50%, by weight of the said substances. The ionizing radiation can be electron beams. In an example, 2% chloral hydrate was homogeneously dissolved in the initial urea-formalin condensation product having a degree of condensation of 3--5. The solution was then irradiated by gamma rays at the dose rate of 4 x 10/sup 4/ r/hour from a /sup 60/Co source with a dose 5.0 x 10/sup 6/ roentgens. A white resinous composition was obtained. (JA)« less

Development of a solar-powered residential air conditioner: Screening analysis

NASA Technical Reports Server (NTRS)

1975-01-01

Screening analysis aimed at the definition of an optimum configuration of a Rankine cycle solar-powered air conditioner designed for residential application were conducted. Initial studies revealed that system performance and cost were extremely sensitive to condensing temperature and to the type of condenser used in the system. Consequently, the screening analyses were concerned with the generation of parametric design data for different condenser approaches; i. e., (1) an ambient air condenser, (2) a humidified ambient air condenser (3) an evaporative condenser, and (4) a water condenser (with a cooling tower). All systems feature a high performance turbocompressor and a single refrigerant (R-11) for the power and refrigeration loops. Data were obtained by computerized methods developed to permit system characterization over a broad range of operating and design conditions. The criteria used for comparison of the candidate system approaches were (1) overall system COP (refrigeration effect/solar heat input), (2) auxiliary electric power for fans and pumps, and (3) system installed cost or cost to the user.

An Unconventional Redox Cross Claisen Condensation-Aromatization of 4-Hydroxyprolines with Ketones.

PubMed

Tang, Mi; Sun, Rengwei; Li, Hao; Yu, Xinhong; Wang, Wei

2017-08-18

Reaction of α-amino acids, particularly prolines and their derivatives with carbonyl compounds via decarboxylative redox process, is a viable strategy for synthesis of structurally diverse nitrogen centered heterocyclics. In these processes, the decarboxylation is the essential driving force for the processes. The realization of the redox process without decarboxylation may offer an opportunity to explore new reactions. Herein, we report the discovery of an unprecedented redox Claisen-type condensation aromatization cascade reaction of 4-substituted 4-hydroxyproline and its esters with unreactive ketones. We found that the use of propionic acid as a catalyst and a co-solvent can change the reaction course. The commonly observed redox decarboxylation and aldol condensation reactions are significantly minimized. Moreover, unreactive ketones can effectively participate in the Claisen condensation reaction. The new reactivity enables a redox cyclization via an unconventional Claisen-type condensation reaction of in situ formed enamine intermediates from ketone precursors with 4-substituted 4-hydroxyproline and its esters as electrophilic acylation partners. Under the reaction conditions, the cascade process proceeds highly regio- and stereoselectively to afford highly synthetically and biologically valued cis-2,3-dihydro-1H-pyrrolizin-1-ones with a broad substrate scope in efficient 'one-pot' operation, whereas such structures generally require multiple steps.

Molecular cloning of metaphase chromosome protein 1 (MCP1), a novel human autoantigen that associates with condensed chromosomes during mitosis.

PubMed

Bronze-da-Rocha, E; Catita, J A; Sunkel, C E

1998-02-01

Systemic lupus erythematosus autoantibodies were used to identify and to characterize new human chromosome-associated proteins. Previous immunolocalization studies in human and murine tissue culture cells showed that some of these monoclonal antibodies recognize nuclear antigens that associate with condensed chromosomes during mitosis. One antibody was selected for screening a human HeLa S3 cDNA expression library, and cDNAs that code for an antigen of 31-33 kDa were isolated. Immunological, biochemical and cell fractionation data indicate that the 31- to 33-kDa antigen corresponds to the chromosome-associated protein recognized by the original monoclonal antibody. Sequence analysis shows that we isolated a novel human gene. Immunolocalization to human tissue culture cells shows that during interphase the antigen is dispersed in the nucleus and that during mitosis it associates exclusively with condensed chromosomes. A similar pattern of localization was also observed in mouse fibroblasts, suggesting that the antigen is conserved among different species. Finally, we show that part of the antigen remains bound to the scaffold/matrix component, even after high salt extraction.

A Climate Statistics Tool and Data Repository

NASA Astrophysics Data System (ADS)

Wang, J.; Kotamarthi, V. R.; Kuiper, J. A.; Orr, A.

2017-12-01

Researchers at Argonne National Laboratory and collaborating organizations have generated regional scale, dynamically downscaled climate model output using Weather Research and Forecasting (WRF) version 3.3.1 at a 12km horizontal spatial resolution over much of North America. The WRF model is driven by boundary conditions obtained from three independent global scale climate models and two different future greenhouse gas emission scenarios, named representative concentration pathways (RCPs). The repository of results has a temporal resolution of three hours for all the simulations, includes more than 50 variables, is stored in Network Common Data Form (NetCDF) files, and the data volume is nearly 600Tb. A condensed 800Gb set of NetCDF files were made for selected variables most useful for climate-related planning, including daily precipitation, relative humidity, solar radiation, maximum temperature, minimum temperature, and wind. The WRF model simulations are conducted for three 10-year time periods (1995-2004, 2045-2054, and 2085-2094), and two future scenarios RCP4.5 and RCP8.5). An open-source tool was coded using Python 2.7.8 and ESRI ArcGIS 10.3.1 programming libraries to parse the NetCDF files, compute summary statistics, and output results as GIS layers. Eight sets of summary statistics were generated as examples for the contiguous U.S. states and much of Alaska, including number of days over 90°F, number of days with a heat index over 90°F, heat waves, monthly and annual precipitation, drought, extreme precipitation, multi-model averages, and model bias. This paper will provide an overview of the project to generate the main and condensed data repositories, describe the Python tool and how to use it, present the GIS results of the computed examples, and discuss some of the ways they can be used for planning. The condensed climate data, Python tool, computed GIS results, and documentation of the work are shared on the Internet.

Dicarboxylic acid anhydride condensation with compounds containing active methylene groups. 4: Some 4-nitrophthalic anhydride condensation reactions

NASA Technical Reports Server (NTRS)

Oskaja, V.; Rotberg, J.

1985-01-01

By 4-nitrophthalic anhydride condensation with acetoacetate in acetic anhydride and triethylamine solution with subsequent breakdown of the intermediate condensation product, 5-nitroindanedione-1,3 was obtained. A 4-nitrophthalic anhydride with acetic anhydride, according to reaction conditions, may yield two products: in the presence of potassium acetate and at high temperatures 4-(or 5-)-nitro-2-acetylbenzoic acid is formed: in the presence of triethylamine and at room temperature 5-( or 6-)-nitrophthalic acetic acid is isolated. A 4-nitrophthalic anhydride and malonic acid in pyridine solution according to temperature yield either 5-( or 6-)-nitrophthalic acetic acid or 4-(or 5-)-nitro-2-acetylbenzoic acid.

Iron Oxide-Supported Copper Oxide Nanoparticles (Nanocat-Fe-CuO): Magnetically Recyclable Catalysts for the Synthesis of Pyrazole Derivatives, 4-Methoxyaniline, and Ullmann-type Condensation Reactions

EPA Science Inventory

An efficient and benign protocol is reported for the synthesis of 4-methoxyaniline, medicinally important pyrazole derivatives, and Ullmann-type condensation reaction using magnetically separable and reusable magnetite-supported copper (nanocat-Fe-CuO) nanoparticles under mild co...

Effective cytoplasmic release of siRNA from liposomal carriers by controlling the electrostatic interaction of siRNA with a charge-invertible peptide, in response to cytoplasmic pH

NASA Astrophysics Data System (ADS)

Itakura, Shoko; Hama, Susumu; Matsui, Ryo; Kogure, Kentaro

2016-05-01

Condensing siRNA with cationic polymers is a major strategy used in the development of siRNA carriers that can avoid degradation by nucleases and achieve effective delivery of siRNA into the cytoplasm. However, ineffective release of siRNA from such condensed forms into the cytoplasm is a limiting step for induction of RNAi effects, and can be attributed to tight condensation of siRNA with the cationic polymers, due to potent electrostatic interactions. Here, we report that siRNA condensed with a slightly acidic pH-sensitive peptide (SAPSP), whose total charge is inverted from positive to negative in response to cytoplasmic pH, is effectively released via electrostatic repulsion of siRNA with negatively charged SAPSP at cytoplasmic pH (7.4). The condensed complex of siRNA and positively-charged SAPSP at acidic pH (siRNA/SAPSP) was found to result in almost complete release of siRNA upon charge inversion of SAPSP at pH 7.4, with the resultant negatively-charged SAPSP having no undesirable interactions with endogenous mRNA. Moreover, liposomes encapsulating siRNA/SAPSP demonstrated knockdown efficiencies comparable to those of commercially available siRNA carriers. Taken together, SAPSP may be very useful as a siRNA condenser, as it facilitates effective cytoplasmic release of siRNA, and subsequent induction of specific RNAi effects.Condensing siRNA with cationic polymers is a major strategy used in the development of siRNA carriers that can avoid degradation by nucleases and achieve effective delivery of siRNA into the cytoplasm. However, ineffective release of siRNA from such condensed forms into the cytoplasm is a limiting step for induction of RNAi effects, and can be attributed to tight condensation of siRNA with the cationic polymers, due to potent electrostatic interactions. Here, we report that siRNA condensed with a slightly acidic pH-sensitive peptide (SAPSP), whose total charge is inverted from positive to negative in response to cytoplasmic pH, is effectively released via electrostatic repulsion of siRNA with negatively charged SAPSP at cytoplasmic pH (7.4). The condensed complex of siRNA and positively-charged SAPSP at acidic pH (siRNA/SAPSP) was found to result in almost complete release of siRNA upon charge inversion of SAPSP at pH 7.4, with the resultant negatively-charged SAPSP having no undesirable interactions with endogenous mRNA. Moreover, liposomes encapsulating siRNA/SAPSP demonstrated knockdown efficiencies comparable to those of commercially available siRNA carriers. Taken together, SAPSP may be very useful as a siRNA condenser, as it facilitates effective cytoplasmic release of siRNA, and subsequent induction of specific RNAi effects. Electronic supplementary information (ESI) available: De-condensation of siRNA cores by addition of heparin; time-lapse moving image of the siRNA release. See DOI: 10.1039/c5nr08365f

{sup 85}Rb tunable-interaction Bose-Einstein condensate machine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Altin, P. A.; Robins, N. P.; Doering, D.

We describe our experimental setup for creating stable Bose-Einstein condensates (BECs) of {sup 85}Rb with tunable interparticle interactions. We use sympathetic cooling with {sup 87}Rb in two stages, initially in a tight Ioffe-Pritchard magnetic trap and subsequently in a weak, large-volume, crossed optical dipole trap, using the 155 G Feshbach resonance to manipulate the elastic and inelastic scattering properties of the {sup 85}Rb atoms. Typical {sup 85}Rb condensates contain 4x10{sup 4} atoms with a scattering length of a=+200a{sub 0}. Many aspects of the design presented here could be adapted to other dual-species BEC machines, including those involving degenerate Fermi-Bose mixtures.more » Our minimalist apparatus is well suited to experiments on dual-species and spinor Rb condensates, and has several simplifications over the {sup 85}Rb BEC machine at JILA, which we discuss at the end of this article.« less

Engineering a Promiscuous Tautomerase into a More Efficient Aldolase for Self-Condensations of Linear Aliphatic Aldehydes.

PubMed

Rahimi, Mehran; van der Meer, Jan-Ytzen; Geertsema, Edzard M; Poelarends, Gerrit J

2017-07-18

The enzyme 4-oxalocrotonate tautomerase (4-OT) from Pseudomonas putida mt-2 takes part in a catabolic pathway for aromatic hydrocarbons, where it catalyzes the conversion of 2hydroxyhexa-2,4-dienedioate into 2-oxohexa-3-enedioate. This tautomerase can also promiscuously catalyze carbon-carbon bond-forming reactions, including various types of aldol reactions, by using its amino-terminal proline as a key catalytic residue. Here, we used systematic mutagenesis to identify two hotspots in 4-OT (Met45 and Phe50) at which single mutations give marked improvements in aldolase activity for the self-condensation of propanal. Activity screening of a focused library in which these two hotspots were varied led to the discovery of a 4-OT variant (M45Y/F50V) with strongly enhanced aldolase activity in the self-condensation of linear aliphatic aldehydes, such as acetaldehyde, propanal, and butanal, to yield α,β-unsaturated aldehydes. With both propanal and benzaldehyde, this double mutant, unlike the previously constructed single mutant F50A, mainly catalyzes the self-condensation of propanal rather than the cross-condensation of propanal and benzaldehyde, thus indicating that it indeed has altered substrate specificity. This variant could serve as a template to create new biocatalysts that lack dehydration activity and possess further enhanced aldolase activity, thus enabling the efficient enzymatic self-coupling of aliphatic aldehydes. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Adaptation of an L-proline adenylation domain to use 4-propyl-L-proline in the evolution of lincosamide biosynthesis.

PubMed

Kadlčík, Stanislav; Kučera, Tomáš; Chalupská, Dominika; Gažák, Radek; Koběrská, Markéta; Ulanová, Dana; Kopecký, Jan; Kutejová, Eva; Najmanová, Lucie; Janata, Jiří

2013-01-01

Clinically used lincosamide antibiotic lincomycin incorporates in its structure 4-propyl-L-proline (PPL), an unusual amino acid, while celesticetin, a less efficient related compound, makes use of proteinogenic L-proline. Biochemical characterization, as well as phylogenetic analysis and homology modelling combined with the molecular dynamics simulation were employed for complex comparative analysis of the orthologous protein pair LmbC and CcbC from the biosynthesis of lincomycin and celesticetin, respectively. The analysis proved the compared proteins to be the stand-alone adenylation domains strictly preferring their own natural substrate, PPL or L-proline. The LmbC substrate binding pocket is adapted to accommodate a rare PPL precursor. When compared with L-proline specific ones, several large amino acid residues were replaced by smaller ones opening a channel which allowed the alkyl side chain of PPL to be accommodated. One of the most important differences, that of the residue corresponding to V306 in CcbC changing to G308 in LmbC, was investigated in vitro and in silico. Moreover, the substrate binding pocket rearrangement also allowed LmbC to effectively adenylate 4-butyl-L-proline and 4-pentyl-L-proline, substrates with even longer alkyl side chains, producing more potent lincosamides. A shift of LmbC substrate specificity appears to be an integral part of biosynthetic pathway adaptation to the PPL acquisition. A set of genes presumably coding for the PPL biosynthesis is present in the lincomycin--but not in the celesticetin cluster; their homologs are found in biosynthetic clusters of some pyrrolobenzodiazepines (PBD) and hormaomycin. Whereas in the PBD and hormaomycin pathways the arising precursors are condensed to another amino acid moiety, the LmbC protein is the first functionally proved part of a unique condensation enzyme connecting PPL to the specialized amino sugar building unit.

High-efficiency free-form condenser overcoming rotational symmetry limitations.

PubMed

Miñano, Juan C; Benítez, Pablo; Blen, José; Santamaría, Asunción

2008-12-08

Conventional condensers using rotational symmetric devices perform far from their theoretical limits when transferring optical power from sources such as arc lamps or halogen bulbs to the rectangular entrance of homogenizing prisms (target). We present a free-form condenser design (calculated with the SMS method) that overcomes the limitations inherent to rotational devices and can send to the target 1.8 times the power sent by an equivalent elliptical condenser for a 4:1 target aspect ratio and 1.5 times for 16:9 target and for practical values of target etendue.

Condensation of Refrigerants on Small Tube Bundles

DTIC Science & Technology

1988-12-01

first comprehensive condensation model was developed by Nusselt in 1916 [Ref. 4] based on the assumption that a quiescent vapor at saturation...vapor is condensed by an auxiliary condenser . The auxiliary condenser is composed of five helically wound copper tubes of 9.53 mm diameter suspended...copper tubing located in the top center of the condenser chamber. The vapor is condensed in the storage cylinder by means of a helical copper coil

Search for the Universal Ancestors

NASA Technical Reports Server (NTRS)

Hartman, H. (Editor); Lawless, J. G. (Editor); Morrison, P. (Editor)

1985-01-01

By its nature, the study of the origins of life is multidisciplinary, requiring contributions from astronomers, biologists, chemists, geologists, physicists, and many others. Partial answers are provided to many questions about organic chemical evolution and the origin of life. It is observed that the gaps in our knowledge concerning the steps from the nonliving to the living are numerous. Among these gaps are: (1) a solar system formation with its accumulation of raw materials; (2) the synthesis of the life forming monomers, such as the amino acids, nucleotides, and lipids; (3) the condensation of these monomers into useful polymers, such as proteins and nucleic acids; (4) the sequestering of these materials into droplets of proteinoid or membrane-like structures; and (5) the development of a chemical memory (the genetic code) to pass on to the progeny the information acquired.

A Three-Dimensional Eulerian Code for Simulation of High-Speed Multimaterial Interactions

DTIC Science & Technology

2011-08-01

PDE -based extension. The extension process is done on only the host cells on a particular processor. After extension the parallel communication is...condensation shocks, explosive debris transport, detonation in heterogeneous media and so on. In these flows complex interactions occur between the...A.22] and ijΩ is the spin tensor. The Jaumann derivative is used to ensure objectivity of the stress tensor with respect to rotation

40 CFR 51.165 - Permit requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ethanol by natural fermentation included in NAICS codes 325193 or 312140; (21) Fossil-fuel boilers (or... processing plants; (24) Glass fiber processing plants; (25) Charcoal production plants; (26) Fossil fuel... source or activity which condense to form particulate matter at ambient temperatures. On or after January...

40 CFR 51.165 - Permit requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ethanol by natural fermentation included in NAICS codes 325193 or 312140; (21) Fossil-fuel boilers (or... processing plants; (24) Glass fiber processing plants; (25) Charcoal production plants; (26) Fossil fuel... source or activity which condense to form particulate matter at ambient temperatures. On or after January...

40 CFR 51.165 - Permit requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ethanol by natural fermentation included in NAICS codes 325193 or 312140; (21) Fossil-fuel boilers (or... processing plants; (24) Glass fiber processing plants; (25) Charcoal production plants; (26) Fossil fuel... source or activity which condense to form particulate matter at ambient temperatures. On or after January...

40 CFR 51.165 - Permit requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... ethanol by natural fermentation included in NAICS codes 325193 or 312140; (21) Fossil-fuel boilers (or... processing plants; (24) Glass fiber processing plants; (25) Charcoal production plants; (26) Fossil fuel... source or activity which condense to form particulate matter at ambient temperatures. On or after January...

40 CFR 51.165 - Permit requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... ethanol by natural fermentation included in NAICS codes 325193 or 312140; (21) Fossil-fuel boilers (or... processing plants; (24) Glass fiber processing plants; (25) Charcoal production plants; (26) Fossil fuel... source or activity which condense to form particulate matter at ambient temperatures. On or after January...

An Experimental Study of Filmwise Condensation on Horizontal Enhanced Condenser Tubing.

DTIC Science & Technology

1979-12-01

with a 51 mm thick sheet of Johns - Manville Aerotube insulation. 22 D. CONDENSATE AND FEEDWATER SYSTEMS The condensate and feedwater systems are shown...desuperheater. The condensate and feedwater lines are insulated with 25.4 mm thick Johns - Manville Aerotube insulation. E. COOLING WATER SYSTEM The cooling

Analyzing communication skills of Pediatric Postgraduate Residents in Clinical Encounter by using video recordings

PubMed Central

Bari, Attia; Khan, Rehan Ahmed; Jabeen, Uzma; Rathore, Ahsan Waheed

2017-01-01

Objective: To analyze communication skills of pediatric postgraduate residents in clinical encounter by using video recordings. Methods: This qualitative exploratory research was conducted through video recording at The Children’s Hospital Lahore, Pakistan. Residents who had attended the mandatory communication skills workshop offered by CPSP were included. The video recording of clinical encounter was done by a trained audiovisual person while the resident was interacting with the patient in the clinical encounter. Data was analyzed by thematic analysis. Results: Initially on open coding 36 codes emerged and then through axial and selective coding these were condensed to 17 subthemes. Out of these four main themes emerged: (1) Courteous and polite attitude, (2) Marginal nonverbal communication skills, (3) Power game/Ignoring child participation and (4) Patient as medical object/Instrumental behaviour. All residents treated the patient as a medical object to reach a right diagnosis and ignored them as a human being. There was dominant role of doctors and marginal nonverbal communication skills were displayed by the residents in the form of lack of social touch, and appropriate eye contact due to documenting notes. A brief non-medical interaction for rapport building at the beginning of interaction was missing and there was lack of child involvement. Conclusion: Paediatric postgraduate residents were polite while communicating with parents and child but lacking in good nonverbal communication skills. Communication pattern in our study was mostly one-way showing doctor’s instrumental behaviour and ignoring the child participation. PMID:29492050

Thermodynamic States in Explosion Fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhl, A L

2010-03-12

We investigate the thermodynamic states occurring in explosion fields from condensed explosive charges. These states are often modeled with a Jones-Wilkins-Lee (JWL) function. However, the JWL function is not a Fundamental Equation of Thermodynamics, and therefore cannot give a complete specification of such states. We use the Cheetah code of Fried to study the loci of states of the expanded detonation products gases from C-4 charges, and their combustion products air. In the Le Chatelier Plane of specific-internal-energy versus temperature, these loci are fit with a Quadratic Model function u(T), which has been shown to be valid for T

Scalable graphene coatings for enhanced condensation heat transfer.

PubMed

Preston, Daniel J; Mafra, Daniela L; Miljkovic, Nenad; Kong, Jing; Wang, Evelyn N

2015-05-13

Water vapor condensation is commonly observed in nature and routinely used as an effective means of transferring heat with dropwise condensation on nonwetting surfaces exhibiting heat transfer improvement compared to filmwise condensation on wetting surfaces. However, state-of-the-art techniques to promote dropwise condensation rely on functional hydrophobic coatings that either have challenges with chemical stability or are so thick that any potential heat transfer improvement is negated due to the added thermal resistance of the coating. In this work, we show the effectiveness of ultrathin scalable chemical vapor deposited (CVD) graphene coatings to promote dropwise condensation while offering robust chemical stability and maintaining low thermal resistance. Heat transfer enhancements of 4× were demonstrated compared to filmwise condensation, and the robustness of these CVD coatings was superior to typical hydrophobic monolayer coatings. Our results indicate that graphene is a promising surface coating to promote dropwise condensation of water in industrial conditions with the potential for scalable application via CVD.

Synthesis of bifunctional molecules containing [12]aneN3 and coumarin moieties as effective DNA condensation agents and new non-viral gene vectors.

PubMed

Yue, Pan; Zhang, Ying; Guo, Zhi-Fo; Cao, Ao-Cheng; Lu, Zhong-Lin; Zhai, Yong-Gong

2015-04-21

A series of bifunctional molecules with different combinations of macrocyclic polyamine [12]aneN3 and coumarin moieties, 4a/b and 5a/b, were synthesized by a two-step copper(I)-mediated alkyne–azide click reactions between 1,3,5-tris(azidomethyl)benzene and Boc-protected N-propynyl-[12]aneN3/7-propynyloxycoumarins. Agarose gel electrophoresis experiments indicated that bifunctional molecules 4b and 5b effectively induced complete plasmid DNA condensation at concentrations up to 40 μM. It was found that the structural variation had a major impact on the condensation behavior of these compounds. The electrostatic interaction involving the [12]aneN3 moiety can be compensated by the binding contribution of the coumarin units during the DNA condensation process. These two types of interaction showed different effects on the reversibility of DNA condensation. Results from studies using dynamic laser scattering, atomic force microscopy, and EB replacement assay further supported the above conclusion. Cytotoxicity assays on bifunctional compounds 4a/b and 5a/b indicated their low cytotoxicity. Results from cellular uptake and cell transfection experiments proved that bifunctional compounds 4b and 5b successfully served as non-viral gene vectors. Furthermore, methyl substituents attached to the coumarin unit (4b and 5b) greatly enhanced their DNA condensation capability and gene transfection. These bifunctional molecules, with the advantages of lower cytotoxicity, good water solubility, and potential structural modification, will have great potential for the development of new non-viral gene delivery agents.

Condensed tannins: A novel rearrangement of procyanidins and prodelphinidins in thiolytic cleavage

Treesearch

G. Wayne McGraw; Jan P. Steynberg; Richard W. Hemingway

1993-01-01

Conditions commonly used for the thiolytic cleavage of interflavanoid bonds of condensed tannins also result in cleavage of the C4 to C10 bond of flavan units. Subsequenet lectrophilic attack of the C4 carbocation on the C2' or C6' of the B-ring, and loss of phloroglucinol (the A-ring), result in the formation of a mixture of 1,3-dithiobenzyl-2,4,s,6-...

The use of chilled condensers for the recovery of perfluorocarbon liquid in an experimental model of perfluorocarbon vapour loss during neonatal partial liquid ventilation

PubMed Central

Dunster, Kimble R; Davies, Mark W; Fraser, John F

2007-01-01

Background Perfluorocarbon (PFC) vapour in the expired gases during partial liquid ventilation should be prevented from entering the atmosphere and recovered for potential reuse. This study aimed to determine how much PFC liquid could be recovered using a conventional humidified neonatal ventilator with chilled condensers in place of the usual expiratory ventilator circuit and whether PFC liquid could be recovered when using the chilled condensers at the ventilator exhaust outlet. Methods Using a model lung, perfluorocarbon vapour loss during humidified partial liquid ventilation of a 3.5 kg infant was approximated. For each test 30 mL of FC-77 was infused into the model lung. Condensers were placed in the expiratory limb of the ventilator circuit and the amounts of PFC (FC-77) and water recovered were measured five times. This was repeated with the condensers placed at the ventilator exhaust outlet. Results When the condensers were used as the expiratory limb, the mean (± SD) volume of FC77 recovered was 16.4 mL (± 0.18 mL). When the condensers were connected to the ventilator exhaust outlet the mean (± SD) volume of FC-77 recovered was 7.6 mL (± 1.14 mL). The volume of FC-77 recovered was significantly higher when the condenser was used as an expiratory limb. Conclusion Using two series connected condensers in the ventilator expiratory line 55% of PFC liquid (FC-77) can be recovered during partial liquid ventilation without altering the function of the of the ventilator circuit. This volume of PFC recovered was just over twice that recovered with the condensers connected to the ventilator exhaust outlet. PMID:17537270

METRRA Signature - Radar Cross Section Measurements. Final Report/ Instruction Manual

DTIC Science & Technology

1978-12-01

Configuration 1 1. 5 Condensed System Parameters 1 1.5.1 Transmitter 1 1.5.2 Receiver 4 2.0 Description 5 V 2.1 Transmitter 5 2.3 Receiver 10 2.4 Antennas 14...System Configuration. 1.4.1 See Figure 1.4.2. 1.5 Condensed System Parameters . 1.5.1 Transmitter. "Mainframe: Applied Microwave Laboratory, Model...for Cubic Defense by Addington Laboratories. Techebychev designs are used for both filters to provide the steepest skirts for given numbers of reactive

Efficacy of testicular sperm chromatin condensation assay using aniline blue-eosin staining in the IVF-ET cycle.

PubMed

Park, Yong-Seog; Kim, Myo Kyung; Lee, Sun-Hee; Cho, Jae Won; Song, In Ok; Seo, Ju Tae

2011-09-01

This study was performed to evaluate testicular sperm chromatin condensation using aniline blue-eosin (AB-E) staining and its effects on IVF-ET. Chromatin condensation was analyzed using AB-E staining in 27 cases of testicular sperm extraction. There were 19 cases of obstructive azoospermia (OA) and 8 cases of non-obstructive azoospermia (NOA) in IVF-ET. Mature sperm heads were stained red-pink whereas immature sperm heads were stained dark blue. The percentage of sperm chromatin condensation was calculated from the ratio of the number of red-pink sperm to the total number of sperm analyzed. The overall percentages of chromatin condensation in OA and NOA were 31.1±11.2% and 26.3±14.4%, respectively. The fertilization rate was significant higher in OA than NOA (p<0.05); however, the rates of good embryos and clinical pregnancy did not show statistical differences. In OA and NOA, statistical differences were not observed in the rate of chromatin condensation, fertilization, good embryos, and clinical pregnancy between the pregnant group and non-pregnant group. Chromatin condensation is less stable than OA and showed a low fertilization rate in NOA. While there were no significant differences in chromatin condensation results between NOA and OA, we propose that a pattern of decreased chromatin condensation in NOA is one of the factors of low fertilization results requiring further study.

Establishment and assessment of code scaling capability

NASA Astrophysics Data System (ADS)

Lim, Jaehyok

In this thesis, a method for using RELAP5/MOD3.3 (Patch03) code models is described to establish and assess the code scaling capability and to corroborate the scaling methodology that has been used in the design of the Purdue University Multi-Dimensional Integral Test Assembly for ESBWR applications (PUMA-E) facility. It was sponsored by the United States Nuclear Regulatory Commission (USNRC) under the program "PUMA ESBWR Tests". PUMA-E facility was built for the USNRC to obtain data on the performance of the passive safety systems of the General Electric (GE) Nuclear Energy Economic Simplified Boiling Water Reactor (ESBWR). Similarities between the prototype plant and the scaled-down test facility were investigated for a Gravity-Driven Cooling System (GDCS) Drain Line Break (GDLB). This thesis presents the results of the GDLB test, i.e., the GDLB test with one Isolation Condenser System (ICS) unit disabled. The test is a hypothetical multi-failure small break loss of coolant (SB LOCA) accident scenario in the ESBWR. The test results indicated that the blow-down phase, Automatic Depressurization System (ADS) actuation, and GDCS injection processes occurred as expected. The GDCS as an emergency core cooling system provided adequate supply of water to keep the Reactor Pressure Vessel (RPV) coolant level well above the Top of Active Fuel (TAF) during the entire GDLB transient. The long-term cooling phase, which is governed by the Passive Containment Cooling System (PCCS) condensation, kept the reactor containment system that is composed of Drywell (DW) and Wetwell (WW) below the design pressure of 414 kPa (60 psia). In addition, the ICS continued participating in heat removal during the long-term cooling phase. A general Code Scaling, Applicability, and Uncertainty (CSAU) evaluation approach was discussed in detail relative to safety analyses of Light Water Reactor (LWR). The major components of the CSAU methodology that were highlighted particularly focused on the scaling issues of experiments and models and their applicability to the nuclear power plant transient and accidents. The major thermal-hydraulic phenomena to be analyzed were identified and the predictive models adopted in RELAP5/MOD3.3 (Patch03) code were briefly reviewed.

21 CFR 177.1580 - Polycarbonate resins.

Code of Federal Regulations, 2013 CFR

2013-04-01

... condensation of 4,4′-iso-propylidenediphenol and carbonyl chloride to which may have been added certain...′-isopro-pylidenediphenol. (3) The condensation of 4,4′-isopro- pylidenediphenol, carbonyl chloride, and 0...

21 CFR 177.1580 - Polycarbonate resins.

Code of Federal Regulations, 2011 CFR

2011-04-01

... condensation of 4,4′-iso-propylidenediphenol and carbonyl chloride to which may have been added certain...′-isopro-pylidenediphenol. (3) The condensation of 4,4′-isopro- pylidenediphenol, carbonyl chloride, and 0...

21 CFR 177.1580 - Polycarbonate resins.

Code of Federal Regulations, 2010 CFR

2010-04-01

... condensation of 4,4′-iso-propylidenediphenol and carbonyl chloride to which may have been added certain...′-isopro-pylidenediphenol. (3) The condensation of 4,4′-isopro- pylidenediphenol, carbonyl chloride, and 0...

21 CFR 177.1580 - Polycarbonate resins.

Code of Federal Regulations, 2012 CFR

2012-04-01

... condensation of 4,4′-iso-propylidenediphenol and carbonyl chloride to which may have been added certain...′-isopro-pylidenediphenol. (3) The condensation of 4,4′-isopro- pylidenediphenol, carbonyl chloride, and 0...

CHEETAH: A next generation thermochemical code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fried, L.; Souers, P.

1994-11-01

CHEETAH is an effort to bring the TIGER thermochemical code into the 1990s. A wide variety of improvements have been made in Version 1.0. We have improved the robustness and ease of use of TIGER. All of TIGER`s solvers have been replaced by new algorithms. We find that CHEETAH solves a wider variety of problems with no user intervention (e.g. no guesses for the C-J state) than TIGER did. CHEETAH has been made simpler to use than TIGER; typical use of the code occurs with the new standard run command. CHEETAH will make the use of thermochemical codes more attractivemore » to practical explosive formulators. We have also made an extensive effort to improve over the results of TIGER. CHEETAH`s version of the BKW equation of state (BKWC) is able to accurately reproduce energies from cylinder tests; something that other BKW parameter sets have been unable to do. Calculations performed with BKWC execute very quickly; typical run times are under 10 seconds on a workstation. In the future we plan to improve the underlying science in CHEETAH. More accurate equations of state will be used in the gas and the condensed phase. A kinetics capability will be added to the code that will predict reaction zone thickness. Further ease of use features will eventually be added; an automatic formulator that adjusts concentrations to match desired properties is planned.« less

Electron emission from condensed phase material induced by fast protons.

PubMed

Shinpaugh, J L; McLawhorn, R A; McLawhorn, S L; Carnes, K D; Dingfelder, M; Travia, A; Toburen, L H

2011-02-01

Monte Carlo track simulation has become an important tool in radiobiology. Monte Carlo transport codes commonly rely on elastic and inelastic electron scattering cross sections determined using theoretical methods supplemented with gas-phase data; experimental condensed phase data are often unavailable or infeasible. The largest uncertainties in the theoretical methods exist for low-energy electrons, which are important for simulating electron track ends. To test the reliability of these codes to deal with low-energy electron transport, yields of low-energy secondary electrons ejected from thin foils have been measured following passage of fast protons. Fast ions, where interaction cross sections are well known, provide the initial spectrum of low-energy electrons that subsequently undergo elastic and inelastic scattering in the material before exiting the foil surface and being detected. These data, measured as a function of the energy and angle of the emerging electrons, can provide tests of the physics of electron transport. Initial measurements from amorphous solid water frozen to a copper substrate indicated substantial disagreement with MC simulation, although questions remained because of target charging. More recent studies, using different freezing techniques, do not exhibit charging, but confirm the disagreement seen earlier between theory and experiment. One now has additional data on the absolute differential electron yields from copper, aluminum and gold, as well as for thin films of frozen hydrocarbons. Representative data are presented.

Electron emission from condensed phase material induced by fast protons†

PubMed Central

Shinpaugh, J. L.; McLawhorn, R. A.; McLawhorn, S. L.; Carnes, K. D.; Dingfelder, M.; Travia, A.; Toburen, L. H.

2011-01-01

Monte Carlo track simulation has become an important tool in radiobiology. Monte Carlo transport codes commonly rely on elastic and inelastic electron scattering cross sections determined using theoretical methods supplemented with gas-phase data; experimental condensed phase data are often unavailable or infeasible. The largest uncertainties in the theoretical methods exist for low-energy electrons, which are important for simulating electron track ends. To test the reliability of these codes to deal with low-energy electron transport, yields of low-energy secondary electrons ejected from thin foils have been measured following passage of fast protons. Fast ions, where interaction cross sections are well known, provide the initial spectrum of low-energy electrons that subsequently undergo elastic and inelastic scattering in the material before exiting the foil surface and being detected. These data, measured as a function of the energy and angle of the emerging electrons, can provide tests of the physics of electron transport. Initial measurements from amorphous solid water frozen to a copper substrate indicated substantial disagreement with MC simulation, although questions remained because of target charging. More recent studies, using different freezing techniques, do not exhibit charging, but confirm the disagreement seen earlier between theory and experiment. One now has additional data on the absolute differential electron yields from copper, aluminum and gold, as well as for thin films of frozen hydrocarbons. Representative data are presented. PMID:21183539

Ion-molecule condensation reactions: a mechanism for organic synthesis in ionized reducing atmospheres.

PubMed

Meot-Ner, M

1978-12-01

The CH3+ ion, formed in ionized methane, undergoes consecutive eliminative condensation reactions with methane to form the carbonium ions C2H5+, i-C3H7+ and t-C4H9+. At T smaller than 500 degrees K, NCH4 greater than 10(16) cm-3 these ions react with NH3 in competitive condensation -- H+ transfer reactions, e.g. C2H5 + NH3 M leads to C2H5NH3+ leads to NH4+ + C2H4 At particle densities of NCH4 smaller than 10(16) cm-3 proton transfer is the only significant reaction channel. At NCH4 greater than 10(17) cm-3 condensation constitutes 5--20% of the overall reactions. The product of the condensation reaction further associates with CO2 to form C2H5NH3+ . CO2; the atomic composition of this cluster ion is identical with the protonated amino acid alanine. The carbonium ions i-C3H7+ and t-C4H9+ condense also with HCN to yield protonated isocyanides. HCNH% also appears to condense with HCN at T greater than 570 degrees K, and form cluster ions with HCN at lower temperatures. The rate constants of the condensation reactions vary with temperature and pressure in a complex manner. Under conditions similar to those on Titan at an altitude of 100 km (T = 100--150 degrees K, NCH4 approximately 10(18) cm-3), with a methane atmosphere containing 1% H2 and traces of NH3 and H2O, ion-molecule condensation reactions followed by H+ transfer are expected to lead to the atmospheric synthesis of C2H6, C3H8, CH3OH, C2H5OH and the terminal ions NH4+, CH3NH3+ and C2H5NH3+. At higher temperatures (250 degrees K smaller than T smaller than 400 degrees K), the synthesis of i-C4H10, i-C3H7OH and t-C4H9OH and of the ions i-C3H7NH3+ and t-C4H9NH3+ is also expected. Electron recombination of the terminal ions may yield amines, imines and nitriles. Cycles of protonation and dissociative recombination of the alkanes and alcohols produced in condensation reactions will also produce unsaturated hydrocarbons, ketones and aldehydes in the ionized atmosphere.

BOXER: Fine-flux Cross Section Condensation, 2D Few Group Diffusion and Transport Burnup Calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

2010-02-01

Neutron transport, calculation of multiplication factor and neutron fluxes in 2-D configurations: cell calculations, 2-D diffusion and transport, and burnup. Preparation of a cross section library for the code BOXER from a basic library in ENDF/B format (ETOBOX).

40 CFR Appendix S to Part 51 - Emission Offset Interpretative Ruling

Code of Federal Regulations, 2011 CFR

2011-07-01

... included in NAICS codes 325193 or 312140; (u) Fossil-fuel boilers (or combination thereof) totaling more... fiber processing plants; (y) Charcoal production plants; (z) Fossil fuel-fired steam electric plants of... and PM10 emissions shall include gaseous emissions from a source or activity which condense to form...

40 CFR Appendix S to Part 51 - Emission Offset Interpretative Ruling

Code of Federal Regulations, 2013 CFR

2013-07-01

... included in NAICS codes 325193 or 312140; (u) Fossil-fuel boilers (or combination thereof) totaling more... fiber processing plants; (y) Charcoal production plants; (z) Fossil fuel-fired steam electric plants of... source or activity, which condense to form particulate matter at ambient temperatures. On or after...

40 CFR Appendix S to Part 51 - Emission Offset Interpretative Ruling

Code of Federal Regulations, 2014 CFR

2014-07-01

... included in NAICS codes 325193 or 312140; (u) Fossil-fuel boilers (or combination thereof) totaling more... fiber processing plants; (y) Charcoal production plants; (z) Fossil fuel-fired steam electric plants of... source or activity, which condense to form particulate matter at ambient temperatures. On or after...

40 CFR Appendix S to Part 51 - Emission Offset Interpretative Ruling

Code of Federal Regulations, 2012 CFR

2012-07-01

... included in NAICS codes 325193 or 312140; (u) Fossil-fuel boilers (or combination thereof) totaling more... fiber processing plants; (y) Charcoal production plants; (z) Fossil fuel-fired steam electric plants of... and PM10 emissions shall include gaseous emissions from a source or activity which condense to form...

40 CFR Appendix S to Part 51 - Emission Offset Interpretative Ruling

Code of Federal Regulations, 2010 CFR

2010-07-01

... included in NAICS codes 325193 or 312140; (u) Fossil-fuel boilers (or combination thereof) totaling more... fiber processing plants; (y) Charcoal production plants; (z) Fossil fuel-fired steam electric plants of... and PM10 emissions shall include gaseous emissions from a source or activity which condense to form...

Synthesis of Fe3O4@P4VP@ZIF-8 core-shell microspheres and their application in a Knoevenagel condensation reaction

NASA Astrophysics Data System (ADS)

Miao, Zongcheng; Yang, Fengxia; Luan, Yi; Shu, Xin; Ramella, Daniele

2017-12-01

In this work, a core-shell magnetic composite Fe3O4@P4VP@ZIF-8 microspheres were successfully designed and synthesized. A polymerization approach on the surface of pre-made Fe3O4 microspheres was employed for the synthesis of Fe3O4@P4VP. The zinc-derived Zeolite Imidazolate Framework (ZIF) shell was introduced through a layer-by-layer strategy. The obtained Fe3O4@P4VP@ZIF-8 core-shell structure was employed as an efficient Knoevenagel condensation catalyst for a variety of aldehydes. Furthermore, the inner P4VP layer also served as a basic additive in the condensation reaction process, while much less homogeneous basic additive was used. High catalytic reaction efficiency was achieved when the P4VP layer was utilized in combination with a Lewis acidity bearing ZIF-8 layer. The Fe3O4@P4VP@ZIF-8 catalyst was tested for recyclability and no drop in the catalytic activity was observed after more than five cycles.

12 CFR 563c.4 - Condensed financial information [Parent only].

Code of Federal Regulations, 2010 CFR

2010-01-01

... ACCOUNTING REQUIREMENTS Form and Content of Financial Statements § 563c.4 Condensed financial information... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Condensed financial information [Parent only... part shall be presented in a note to the financial statements when the restricted net assets (17 CFR...

Effects of breathing pattern and inspired air conditions on breath condensate volume, pH, nitrite, and protein concentrations.

PubMed

McCafferty, J B; Bradshaw, T A; Tate, S; Greening, A P; Innes, J A

2004-08-01

The effects of breathing pattern and inspired air conditions on the volume and content of exhaled breath condensate (EBC) were investigated. Total exhaled water (TEW), EBC volume, pH, nitrite and protein concentrations were measured in three groups of 10 healthy subjects breathing into a condenser at different target minute ventilations (Vm), tidal volumes (Vt), and inspired air conditions. The volumes of both TEW and EBC increased significantly with Vm. For Vm 7.5, 15 and 22.5 l/min, mean (SD) EBC was 627 (258) microl, 1019 (313) microl, and 1358 (364) microl, respectively (p<0.001) and TEW was 1879 (378) microl, 2986 (496) microl, and 4679 (700) microl, respectively (p<0.001). TEW was significantly higher than EBC, reflecting a condenser efficiency of 40% at a target Vm of 7.5 l/min which reduced to 29% at Vm 22.5 l/min. Lower Vt gave less TEW than higher Vt (26.6 v 30.7 microl/l, mean difference 4.1 (95% CI 2.6 to 5.6), p<0.001) and a smaller EBC volume (4.3 v 7.6 microl/l, mean difference 3.4 (95% CI 2.3 to 4.5), p<0.001). Cooler and drier inspired air yielded less water vapour and less breath condensate than standard conditions (p<0.05). Changes in the breathing pattern had no effect on EBC protein and nitrite concentrations and pH. These results show that condensate volume can be increased by using high Vt and increased Vm without compromising the dilution of the sample.

Condensation patterns of prophase/prometaphase chromosome are correlated with H4K5 histone acetylation and genomic DNA contents in plants.

PubMed

Feitoza, Lidiane; Costa, Lucas; Guerra, Marcelo

2017-01-01

Mitotic prophase chromosome condensation plays an essential role in nuclear division being therefore regulated by highly conserved mechanisms. However, degrees of chromatin condensation in prophase-prometaphase cells may vary along the chromosomes resulting in specific condensation patterns. We examined different condensation patterns (CPs) of prophase and prometaphase chromosomes and investigated their relationship with genome size and distribution of histone H4 acetylated at lysine 5 (H4K5ac) in 17 plant species. Our results showed that most species with small genomes (2C < 5 pg) (Arachis pusilla, Bixa orellana, Costus spiralis, Eleutherine bulbosa, Indigofera campestris, Phaseolus lunatus, P. vulgaris, Poncirus trifoliata, and Solanum lycopersicum) displayed prophase chromosomes with late condensing terminal regions that were highly enriched in H4K5ac, and early condensing regions with apparently non-acetylated proximal chromatin. The species with large genomes (Allium cepa, Callisia repens, Araucaria angustifolia and Nothoscordum pulchellum) displayed uniformly condensed and acetylated prophase/prometaphase chromosomes. Three species with small genomes (Eleocharis geniculata, Rhynchospora pubera, and R. tenuis) displayed CP and H4K5ac labeling patterns similar to species with large genomes, whereas a forth species (Emilia sonchifolia) exhibited a gradual chromosome labeling, being more acetylated in the terminal regions and less acetylated in the proximal ones. The nucleolus organizer chromatin was the only chromosomal region that in prometaphase or metaphase could be hyperacetylated, hypoacetylated or non-acetylated, depending on the species. Our data indicate that the CP of a plant chromosome complement is influenced but not exclusively determined by nuclear and chromosomal DNA contents, whereas the CP of individual chromosomes is clearly correlated with H4K5ac distribution.

Condensation patterns of prophase/prometaphase chromosome are correlated with H4K5 histone acetylation and genomic DNA contents in plants

PubMed Central

Feitoza, Lidiane; Costa, Lucas

2017-01-01

Mitotic prophase chromosome condensation plays an essential role in nuclear division being therefore regulated by highly conserved mechanisms. However, degrees of chromatin condensation in prophase-prometaphase cells may vary along the chromosomes resulting in specific condensation patterns. We examined different condensation patterns (CPs) of prophase and prometaphase chromosomes and investigated their relationship with genome size and distribution of histone H4 acetylated at lysine 5 (H4K5ac) in 17 plant species. Our results showed that most species with small genomes (2C < 5 pg) (Arachis pusilla, Bixa orellana, Costus spiralis, Eleutherine bulbosa, Indigofera campestris, Phaseolus lunatus, P. vulgaris, Poncirus trifoliata, and Solanum lycopersicum) displayed prophase chromosomes with late condensing terminal regions that were highly enriched in H4K5ac, and early condensing regions with apparently non-acetylated proximal chromatin. The species with large genomes (Allium cepa, Callisia repens, Araucaria angustifolia and Nothoscordum pulchellum) displayed uniformly condensed and acetylated prophase/prometaphase chromosomes. Three species with small genomes (Eleocharis geniculata, Rhynchospora pubera, and R. tenuis) displayed CP and H4K5ac labeling patterns similar to species with large genomes, whereas a forth species (Emilia sonchifolia) exhibited a gradual chromosome labeling, being more acetylated in the terminal regions and less acetylated in the proximal ones. The nucleolus organizer chromatin was the only chromosomal region that in prometaphase or metaphase could be hyperacetylated, hypoacetylated or non-acetylated, depending on the species. Our data indicate that the CP of a plant chromosome complement is influenced but not exclusively determined by nuclear and chromosomal DNA contents, whereas the CP of individual chromosomes is clearly correlated with H4K5ac distribution. PMID:28854212

CHEETAH 1.0 user`s manual

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fried, L.E.

1994-06-24

CHEETAH is an effort to bring the TIGER thermochemical code into the 1990s. A wide variety of improvements have been made in Version 1.0, and a host of others will be implemented in the future. In CHEETAH 1.0 I have improved the robustness and ease of use of TIGER. All of TIGER`s solvers have been replaced by new algorithms. I find that CHEETAH solves a wider variety of problems with no user intervention (e.g. no guesses for the C-J state) than TIGER did. CHEETAH has been made simpler to use than TIGER; typical use of the code occurs with themore » new standard run command. I hope that CHEETAH makes the use of thermochemical codes more attractive to practical explosive formulators. In the future I plan to improve the underlying science in CHEETAH. More accurate equations of state will be used in the gas and the condensed phase. A kinetics capability will be added to the code that will predict reaction zone thickness. CHEETAH is currently a numerical implementation of C-J theory. It will,become an implementation of ZND theory. Further ease of use features will eventually be added; an automatic formulator that adjusts concentrations to match desired properties is planned.« less

Recent Updates to the MELCOR 1.8.2 Code for ITER Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Merrill, Brad J

This report documents recent changes made to the MELCOR 1.8.2 computer code for application to the International Thermonuclear Experimental Reactor (ITER), as required by ITER Task Agreement ITA 81-18. There are four areas of change documented by this report. The first area is the addition to this code of a model for transporting HTO. The second area is the updating of the material oxidation correlations to match those specified in the ITER Safety Analysis Data List (SADL). The third area replaces a modification to an aerosol tranpsort subroutine that specified the nominal aerosol density internally with one that now allowsmore » the user to specify this density through user input. The fourth area corrected an error that existed in an air condensation subroutine of previous versions of this modified MELCOR code. The appendices of this report contain FORTRAN listings of the coding for these modifications.« less

Spectral Properties of Gas-phase Condensed Fullerene-like Carbon Nanoparticles from Far-ultraviolet to Infrared Wavelengths

NASA Astrophysics Data System (ADS)

Jäger, C.; Mutschke, H.; Henning, Th.; Huisken, F.

2008-12-01

Carbon solids are ubiquitous material in interstellar space. However, the formation pathway of carbonaceous matter in astrophysical environments, as well as in terrestrial gas-phase condensation reactions, is not yet understood. Laser ablation of graphite in different quenching gas atmospheres, such as pure He, He/H2, and He/H2O at varying pressures, is used to synthesize very small, fullerene-like carbon nanoparticles. The particles are characterized by very small diameters between 1 and 4 nm and a disturbed onion-like structure. The soot particles extracted from the condensation zone obviously represent a very early stage of particle condensation. The spectral properties have been measured from the far-ultraviolet (FUV; λ = 120 nm) to the mid-infrared (MIR; λ = 15 μm). The seedlike soot particles show strong absorption bands in the 3.4 μm range. The profile and the intensity pattern of the 3.4 μm band of the diffuse interstellar medium can be well reproduced by the measured 3.4 μm profile of the condensed particles; however, all the carbon which is left to form solids is needed to fit the intensity of the interstellar bands. In contrast to the assumption that onion-like soot particles could be the carriers of the interstellar ultraviolet (UV) bump, our very small onion-like carbon nanoparticles do not show distinct UV bands due to (π-π*) transitions.

Sensitivity analysis and economic optimization studies of inverted five-spot gas cycling in gas condensate reservoir

NASA Astrophysics Data System (ADS)

Shams, Bilal; Yao, Jun; Zhang, Kai; Zhang, Lei

2017-08-01

Gas condensate reservoirs usually exhibit complex flow behaviors because of propagation response of pressure drop from the wellbore into the reservoir. When reservoir pressure drops below the dew point in two phase flow of gas and condensate, the accumulation of large condensate amount occurs in the gas condensate reservoirs. Usually, the saturation of condensate accumulation in volumetric gas condensate reservoirs is lower than the critical condensate saturation that causes trapping of large amount of condensate in reservoir pores. Trapped condensate often is lost due to condensate accumulation-condensate blockage courtesy of high molecular weight, heavy condensate residue. Recovering lost condensate most economically and optimally has always been a challenging goal. Thus, gas cycling is applied to alleviate such a drastic loss in resources. In gas injection, the flooding pattern, injection timing and injection duration are key parameters to study an efficient EOR scenario in order to recover lost condensate. This work contains sensitivity analysis on different parameters to generate an accurate investigation about the effects on performance of different injection scenarios in homogeneous gas condensate system. In this paper, starting time of gas cycling and injection period are the parameters used to influence condensate recovery of a five-spot well pattern which has an injection pressure constraint of 3000 psi and production wells are constraint at 500 psi min. BHP. Starting injection times of 1 month, 4 months and 9 months after natural depletion areapplied in the first study. The second study is conducted by varying injection duration. Three durations are selected: 100 days, 400 days and 900 days. In miscible gas injection, miscibility and vaporization of condensate by injected gas is more efficient mechanism for condensate recovery. From this study, it is proven that the application of gas cycling on five-spot well pattern greatly enhances condensate recovery preventing financial, economic and resource loss that previously occurred.

Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edward Levy; Harun Bilirgen; John DuPoint

2011-03-31

Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: (1) An expanded data base on water and acid condensation characteristicsmore » of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing high-moisture, low rank coals. (2) Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. (3) Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. (4) Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. (5) Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. (6) Condensed flue gas water treatment needs and costs. (7) Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. (8) Results of cost-benefit studies of condensing heat exchangers.« less

Experimental study of condensate subcooling with the use of a model of an air-cooled condenser

NASA Astrophysics Data System (ADS)

Sukhanov, V. A.; Bezukhov, A. P.; Bogov, I. A.; Dontsov, N. Y.; Volkovitsky, I. D.; Tolmachev, V. V.

2016-01-01

Water-supply deficit is now felt in many regions of the world. This hampers the construction of new steam-turbine and combined steam-and-gas thermal power plants. The use of dry cooling systems and, specifically, steam-turbine air-cooled condensers (ACCs) expands the choice of sites for the construction of such power plants. The significance of condensate subcooling Δ t as a parameter that negatively affects the engineering and economic performance of steam-turbine plants is thereby increased. The operation and design factors that influence the condensate subcooling in ACCs are revealed, and the research objective is, thus, formulated properly. The indicated research was conducted through physical modeling with the use of the Steam-Turbine Air-Cooled Condenser Unit specialized, multipurpose, laboratory bench. The design and the combined schematic and measurement diagram of this test bench are discussed. The experimental results are presented in the form of graphic dependences of the condensate subcooling value on cooling ratio m and relative weight content ɛ' of air in steam at the ACC inlet at different temperatures of cooling air t ca ' . The typical ranges of condensate subcooling variation (4 ≤ Δ t ≤ 6°C, 2 ≤ Δ t ≤ 4°C, and 0 ≤ Δ t ≤ 2°C) are identified based on the results of analysis of the attained Δ t levels in the ACC and numerous Δ t reduction estimates. The corresponding ranges of cooling ratio variation at different temperatures of cooling air at the ACC inlet are specified. The guidelines for choosing the adjusted ranges of cooling ratio variation with account of the results of experimental studies of the dependences of the absolute pressure of the steam-air mixture in the top header of the ACC and the heat flux density on the cooling ratio at different temperatures of cooling air at the ACC inlet are given.

Comparison of the solid-phase fragment condensation and phase-change approaches in the synthesis of salmon I calcitonin.

PubMed

Gatos, D; Tzavara, C

2001-02-01

Salmon I calcitonin was synthesized using both phase-change and conventional solid-phase fragment condensation (SPFC) approaches, utilizing the Rink amide linker (Fmoc-amido-2,4-dimethoxybenzyl-4-phenoxyacetic acid) combined with 2-chlorotrityl resin and the Fmoc/tBu(Trt)-based protection scheme. Phase-change synthesis, performed by the selective detachment of the fully protected C-terminal 22-mer peptide-linker from the resin and subsequent condensation in solution with the N-terminal 1-10 fragment, gave a product of slightly less purity (85 vs. 92%) than the corresponding synthesis on the solid-phase. In both cases salmon I calcitonin was easily obtained in high purity.

27 CFR 4.10 - Meaning of terms.

Code of Federal Regulations, 2014 CFR

2014-04-01

... part. Act. The Federal Alcohol Administration Act. Added brandy. Brandy or wine spirits for use in... water. Restored pure condensed must. Pure condensed must to which has been added an amount of water not exceeding the amount removed in the dehydration process. Sugar. Pure cane, beet, or dextrose sugar in dry...

27 CFR 4.10 - Meaning of terms.

Code of Federal Regulations, 2012 CFR

2012-04-01

... part. Act. The Federal Alcohol Administration Act. Added brandy. Brandy or wine spirits for use in... water. Restored pure condensed must. Pure condensed must to which has been added an amount of water not exceeding the amount removed in the dehydration process. Sugar. Pure cane, beet, or dextrose sugar in dry...

27 CFR 4.10 - Meaning of terms.

Code of Federal Regulations, 2013 CFR

2013-04-01

... part. Act. The Federal Alcohol Administration Act. Added brandy. Brandy or wine spirits for use in... water. Restored pure condensed must. Pure condensed must to which has been added an amount of water not exceeding the amount removed in the dehydration process. Sugar. Pure cane, beet, or dextrose sugar in dry...

27 CFR 4.10 - Meaning of terms.

Code of Federal Regulations, 2011 CFR

2011-04-01

... part. Act. The Federal Alcohol Administration Act. Added brandy. Brandy or wine spirits for use in... water. Restored pure condensed must. Pure condensed must to which has been added an amount of water not exceeding the amount removed in the dehydration process. Sugar. Pure cane, beet, or dextrose sugar in dry...

Rapid quantification of proanthocyanidins (condensed tannins) with a continuous flow analyzer

Treesearch

James K. Nitao; Bruce A. Birr; Muraleedharan G. Nair; Daniel A. Herms; William J. Mattson

2001-01-01

Proanthocyanidins (condensed tannins) frequently need to be quantified in large numbers of samples in food, plant, and environmental studies. An automated colorimetric method to quantify proanthocyanidins with sulfuric acid (H2SO4) was therefore developed for use in a continuous flow analyzer. Assay conditions were...

A prebiotic template-directed peptide synthesis based on amyloids.

PubMed

Rout, Saroj K; Friedmann, Michael P; Riek, Roland; Greenwald, Jason

2018-01-16

The prebiotic replication of information-coding molecules is a central problem concerning life's origins. Here, we report that amyloids composed of short peptides can direct the sequence-selective, regioselective and stereoselective condensation of amino acids. The addition of activated DL-arginine and DL-phenylalanine to the peptide RFRFR-NH 2 in the presence of the complementary template peptide Ac-FEFEFEFE-NH 2 yields the isotactic product FRFRFRFR-NH 2 , 1 of 64 possible triple addition products, under conditions in which the absence of template yields only single and double additions of mixed stereochemistry. The templating mechanism appears to be general in that a different amyloid formed by (Orn)V(Orn)V(Orn)V(Orn)V-NH 2 and Ac-VDVDVDVDV-NH 2 is regioselective and stereoselective for N-terminal, L-amino-acid addition while the ornithine-valine peptide alone yields predominantly sidechain condensation products with little stereoselectivity. Furthermore, the templating reaction is stable over a wide range of pH (5.6-8.6), salt concentration (0-4 M NaCl), and temperature (25-90 °C), making the amyloid an attractive model for a prebiotic peptide replicating system.

Assessment of the TRACE Reactor Analysis Code Against Selected PANDA Transient Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zavisca, M.; Ghaderi, M.; Khatib-Rahbar, M.

2006-07-01

The TRACE (TRAC/RELAP Advanced Computational Engine) code is an advanced, best-estimate thermal-hydraulic program intended to simulate the transient behavior of light-water reactor systems, using a two-fluid (steam and water, with non-condensable gas), seven-equation representation of the conservation equations and flow-regime dependent constitutive relations in a component-based model with one-, two-, or three-dimensional elements, as well as solid heat structures and logical elements for the control system. The U.S. Nuclear Regulatory Commission is currently supporting the development of the TRACE code and its assessment against a variety of experimental data pertinent to existing and evolutionary reactor designs. This paper presents themore » results of TRACE post-test prediction of P-series of experiments (i.e., tests comprising the ISP-42 blind and open phases) conducted at the PANDA large-scale test facility in 1990's. These results show reasonable agreement with the reported test results, indicating good performance of the code and relevant underlying thermal-hydraulic and heat transfer models. (authors)« less

Genotoxicity of waterpipe smoke in buccal cells and peripheral blood leukocytes as determined by comet assay.

PubMed

Al-Amrah, Hadba Jar-Allah; Aboznada, Osama Abdullah; Alam, Mohammad Zubair; ElAssouli, M-Zaki Mustafa; Mujallid, Mohammad Ibrahim; ElAssouli, Sufian Mohamad

2014-12-01

Waterpipe smoke causes DNA damage in peripheral blood leukocytes and in buccal cells of smokers. To determine the exposure effect of waterpipe smoke on buccal cells and peripheral blood leukocytes in regard to DNA damage using comet assay. The waterpipe smoke condensates were analyzed by gas chromatography-mass spectrometry (GC-MS). The study was performed on 20 waterpipe smokers. To perform comet assay on bucaal cells of smokers, 10 µl of cell suspension was mixed with 85 µl of pre-warmed 1% low melting agarose, applied to comet slide and electrophoresed. To analyze the effect of smoke condensate in vitro, 1 ml of peripheral blood was mixed with 10 µl of smoke condensate and subjected for comet assay. The GC-MS analysis revealed the presence of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4on, nicotine, hydroxymethyl furancarboxaldehyde and 3-ethoxy-4-hydroxybenzaldehyde in the smoke condensates. Waterpipe smoking caused DNA damage in vivo in buccal cells of smokers. The tail moment and tail length in buccal cells of smokers were 186 ± 26 and 456 ± 71, respectively, which are higher than control. The jurak and moassel smoke condensates were found to cause DNA damage in peripheral blood leukocytes. The moassel smoke condensate was more damaging. There is wide misconception that waterpipe smoking is not as harmful as cigarette smoking. This study demonstrated that waterpipe smoke induced DNA damage in exposed cells. Waterpipe smokes cause DNA damage in buccal cells. The smoke condensate of both jurak and moassel caused comet formation suggesting DNA damage in peripheral blood leukocytes.

Venting of attics & cathedral ceilings

Treesearch

William B. Rose; Anton TenWolde

2002-01-01

Current building codes typically call for attic ventilation to minimize condensation on the underside of roof sheathing. Summer cooling of attic air, minimizing ice dams, and extending the service life of the roof materials often are cited as additional benefits of attic ventilation. In fact, most asphalt shingle manufacturers warrant their products only for ventilated...

Analysis of medium-BTU gasification condensates, June 1985-June 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elliott, D.C.

1987-05-01

This report provides the final results of chemical and physical analysis of condensates from biomass gasification systems which are part of the US Department of Energy Biomass Thermochemical Conversion Program. The work described in detail in this report involves extensive analysis of condensates from four medium-BTU gasifiers. The analyses include elemental analysis, ash, moisture, heating value, density, specific chemical analysis, ash, moisture, heating value, density, specific chemical analysis (gas chromatography/mass spectrometry, infrared spectrophotometry, Carbon-13 nuclear magnetic resonance spectrometry) and Ames Assay. This work was an extension of a broader study earlier completed of the condensates of all the gasifers andmore » pyrolyzers in the Biomass Thermochemical Conversion Program. The analytical data demonstrates the wide range of chemical composition of the organics recoverd in the condensates and suggests a direct relationship between operating temperature and chemical composition of the condensates. A continuous pathway of thermal degradation of the tar components as a function of temperature is proposed. Variations in the chemical composition of the organic in the tars are reflected in the physical properties of tars and phase stability in relation to water in the condensate. The biological activity appears to be limited to the tars produced at high temperatures as a result of formation of polycyclic aromatic hydrocarbons in high concentrations. Future studies of the time/temperature relationship to tar composition and the effect of processing atmosphere should be undertaken. Further processing of the condensates either as wastewater treatment or upgrading of the organics to useful products is also recommended. 15 refs., 4 figs., 4 tabs.« less

Influence of condensation and latent heat release upon barotropic and baroclinic instabilities of vortices in a rotating shallow water f-plane model

NASA Astrophysics Data System (ADS)

Rostami, Masoud; Zeitlin, Vladimir

2017-01-01

Analysis of the influence of condensation and related latent heat release upon developing barotropic and baroclinic instabilities of large-scale low Rossby-number shielded vortices on the f-plane is performed within the moist-convective rotating shallow water model, in its barotropic (one-layer) and baroclinic (two-layer) versions. Numerical simulations with a high-resolution well-balanced finite-volume code, using a relaxation parameterisation for condensation, are made. Evolution of the instability in four different environments, with humidity (i) behaving as passive scalar, (ii) subject to condensation beyond a saturation threshold, (iii) subject to condensation and evaporation, with three different parameterisations of the latter, are inter-compared. The simulations are initialised with unstable modes determined from the detailed linear stability analysis in the "dry" version of the model. In a configuration corresponding to low-level mid-latitude atmospheric vortices, it is shown that the known scenario of evolution of barotropically unstable vortices, consisting in formation of a pair of dipoles (dipolar breakdown) is substantially modified by condensation and related moist convection, especially in the presence of surface evaporation. No enhancement of the instability due to precipitation was detected in this case. Cyclone-anticyclone asymmetry with respect to sensitivity to the moist effects is evidenced. It is shown that inertia-gravity wave emission during the vortex evolution is enhanced by the moist effects. In the baroclinic configuration corresponding to idealised cut-off lows in the atmosphere, it is shown that the azimuthal structure of the leading unstable mode is sensitive to the details of stratification. Scenarios of evolution are completely different for different azimuthal structures, one leading to dipolar breaking, and another to tripole formation. The effects of moisture considerably enhance the perturbations in the lower layer, especially in the tripole formation scenario.

Effects of breathing pattern and inspired air conditions on breath condensate volume, pH, nitrite, and protein concentrations

PubMed Central

McCafferty, J; Bradshaw, T; Tate, S; Greening, A; Innes, J

2004-01-01

Background: The effects of breathing pattern and inspired air conditions on the volume and content of exhaled breath condensate (EBC) were investigated. Methods: Total exhaled water (TEW), EBC volume, pH, nitrite and protein concentrations were measured in three groups of 10 healthy subjects breathing into a condenser at different target minute ventilations (Vm), tidal volumes (Vt), and inspired air conditions. Results: The volumes of both TEW and EBC increased significantly with Vm. For Vm 7.5, 15 and 22.5 l/min, mean (SD) EBC was 627 (258) µl, 1019 (313) µl, and 1358 (364) µl, respectively (p<0.001) and TEW was 1879 (378) µl, 2986 (496) µl, and 4679 (700) µl, respectively (p<0.001). TEW was significantly higher than EBC, reflecting a condenser efficiency of 40% at a target Vm of 7.5 l/min which reduced to 29% at Vm 22.5 l/min. Lower Vt gave less TEW than higher Vt (26.6 v 30.7 µl/l, mean difference 4.1 (95% CI 2.6 to 5.6), p<0.001) and a smaller EBC volume (4.3 v 7.6 µl/l, mean difference 3.4 (95% CI 2.3 to 4.5), p<0.001). Cooler and drier inspired air yielded less water vapour and less breath condensate than standard conditions (p<0.05). Changes in the breathing pattern had no effect on EBC protein and nitrite concentrations and pH. Conclusion: These results show that condensate volume can be increased by using high Vt and increased Vm without compromising the dilution of the sample. PMID:15282391

[The balance of harmful trace contaminants between the air humidity condensate and air in a simulator of the Mir orbit station moisture condensation unit].

PubMed

Zlotopol'skiĭ, V M; Smolenskaia, T S

2000-01-01

Subject of the investigation was the balance of harmful trace contaminants (HTC) between the air moisture condensate and air in a simulator of the MIR moisture condensation unit. Experiments involved various classes of water-solvent compounds including alcohols (C1-C4), ketons (C1-C2), aldehydes (C1-C2), fatty acids (C2-C4), esters (acetates C4-C6), and ammonium. For most of the compounds, removal efficiency correlates with air humidity and virtually does not depend on the HTC concentration within the range of 0.25 to 59.1 mg/m3.

Spectroscopic studies of non-volatile residue formed by photochemistry of solid C4N2: A model of condensed aerosol formation on Titan

NASA Astrophysics Data System (ADS)

Couturier-Tamburelli, Isabelle; Gudipati, Murthy S.; Lignell, Antti; Jacovi, Ronen; Piétri, Nathalie

2014-05-01

Following our recent communication (Gudipati, M.S. et al. [2013]. Nat. Commun. 4, 1648. http://dx.doi.org/10.1038/ncomms2649) on the discovery of condensed-phase non-volatile polymeric material with similar spectral features as tholins, we present here a comprehensive spectroscopic study of photochemical formation of polymeric material from condensed dicyanoacetylene (C4N2) ice films. C4N2 is chosen as starting material for the laboratory simulations because of the detection of this and similar molecules (nitriles and cyanoacetylenes) in Titan’s atmosphere. UV-Vis and infrared spectra obtained during long-wavelength (>300 nm) photon irradiation and subsequent warming of the ice films are used to analyze changes in C4N2 ice, evolution of tholins, and derive photopolymerization mechanisms. Our data analysis revealed that many processes occur during the photolysis of condensed Titan’s aerosol analogs, including isomerization and polymerization leading to the formation of long-chain as well as aromatic cyclic polymer molecules. In the light of tremendous new data from the Cassini mission on the seasonal variations in Titan’s atmosphere, our laboratory study and its results provide fresh insight into the formation and evolution of aerosols and haze in Titan’s atmosphere.

Gravity Effects in Condensing and Evaporating Films

NASA Technical Reports Server (NTRS)

Hermanson, J. C.; Som, S. M.; Allen, J. S.; Pedersen, P. C.

2004-01-01

A general overview of gravity effects in condensing and evaporating films is presented. The topics include: 1) Research Overview; 2) NASA Recognizes Critical Need for Condensation & Evaporation Research to Enable Human Exploration of Space; 3) Condensation and Evaporation Research in Reduced Gravity is Enabling for AHST Technology Needs; 4) Differing Role of Surface Tension on Condensing/Evaporating Film Stability; 5) Fluid Mechanisms in Condensing and Evaporating Films in Reduced Gravity; 6) Research Plan; 7) Experimental Configurations for Condensing Films; 8) Laboratory Condensation Test Cell; 9) Aircraft Experiment; 10) Condensation Study Current Test Conditions; 11) Diagnostics; 12) Shadowgraph Images of Condensing n- pentane Film in Unstable (-1g) Configuration; 13) Condensing n-Pentane Film in Normal Gravity (-1g) at Constant Pressure; 14) Condensing n-Pentane Film in Normal Gravity (-1g) with Cyclic Pressure; 15) Non-condensing Pumped Film in Normal Gravity (-1g); 16) Heat Transfer Coefficient in Developing, Unstable Condensing Film in Normal Gravity; 17) Heat Transfer for Unsteady Condensing Film (-1g); 18) Ultrasound Measurement of Film Thickness N-pentane Film, Stable (+1g) Configuration; and 19) Ultrasound Measurement of Film Thickness N-pentane Film, Unstable (-1g) Configuration.

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins.

Code of Federal Regulations, 2014 CFR

2014-04-01

...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION...,4′-isopropylidenediphenol-epichlorohydrin epoxy resins. The resins identified in paragraph (a) of... condensation of xylene-formaldehyde resin and 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins, to...

Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes.

PubMed

Liu, Wenxia; Zheng, Minghui; Liu, Wenbin; Ma, Xiaodong; Qian, Yong; Zhang, Bing

2008-01-01

Polychlorinated diphenyl ethers (PCDEs), which are among the members of persistent organic pollutants, and PCDEs have been determined in a number of environmental samples. The main possible sources are the technical production of chlorinated phenols and all processes of incomplete combustion. PCDEs were observed in the fly ash from a municipal waste incinerator (MWI). It was speculated that the condensation of chlorophenols with chlorobenzenes occurred via PCDEs to form polychlorinated dibenzofurans (PCDFs). Nevertheless, PCDEs formation from condensation of chlorophenols with chlorobenzenes has not been confirmed by experimental observation. The objective of this paper is to investigate the formation mechanism of PCDEs from the condensation of chlorophenols with chlorobenzenes. The results are expected to be helpful in understanding the formation of PCDEs and in controlling and abating PCDEs emissions from MWI. The pyrolysis of pentachlorophenol (PCP) and/or polychlorobenzenes (PCBz) was carried out in a sealed glass tube. The reaction products were extracted and purified with K2CO3 solution. The samples were concentrated and then cleaned up on an alumina column. GC/MS was used for identification and quantification of reaction products. The results showed that the pyrolysis of hexachlorobenzene (HCB) at 340 degrees C for 6 h led to the formation of decachlorodiphenyl ether (DCDE) (2.41 microg/mg) and octachlorodibenzo-p-dioxins (OCDD) (0.24 micropg/mg), while the pyrolysis of PCP yielded DCDE (13.08 microg/mg) and OCDD (180.13 microg/mg). In addition, the amount of DCDE formation from the pyrolysis of the mixture of PCP and HCB was 4.65 times higher than the total amount of DCDE formation from the pyrolysis of HCB and PCP, respectively. This indicated that PCP and HCB were prone to condensation and formation of DCDE. DCDE was the main congener of PCDEs from condensation of PCP with HCB at 340, 400 and 450 degrees C. A small amount of nonachlorodiphenyl ether (NCDE) was formed by dechlorination reaction at 450 degrees C. The condensation of PCP with 1,2,4,5-tetrachlorobenzene (Cl4Bz) formed 2,2',3,4,4',5,5',6-octachlorodiphenyl ether (OCDE). Small amounts of heptachlorodiphenyl ether (HpCDE) and hexachlorodiphenyl ether (HxCDE) were detected at 450 degrees C. Meanwhile, polychlorinated dibenzo-p-dioxins (PCDDs) and PCDFs were detected from the condensation of PCP and PCBz. Experimental studies clarified the behavior of the formation of PCDEs from condensation of polychlorophenols and PCBz. The condensation of polychlorophenols with PCBz formed PCDEs through elimination of HCl between polychlorophenols and PCBz molecules. Another pathway of PCDEs formation was elimination of H2O between two polychlorophenol molecules. In addition, dechlorination processes had caused the specific homologous pattern of PCDEs under higher temperatures.

Toxicological and chemical characterization of the process stream materials and gas combustion products of an experimental low-btu coal gasifier.

PubMed

Benson, J M; Hanson, R L; Royer, R E; Clark, C R; Henderson, R F

1984-04-01

The process gas stream of an experimental pressurized McDowell-Wellman stirred-bed low-Btu coal gasifier, and combustion products of the clean gas were characterized as to their mutagenic properties and chemical composition. Samples of aerosol droplets condensed from the gas were obtained at selected positions along the process stream using a condenser train. Mutagenicity was assessed using the Ames Salmonella mammalian microsome mutagenicity assay (TA98, with and without rat liver S9). All materials required metabolic activation to be mutagenic. Droplets condensed from gas had a specific mutagenicity of 6.7 revertants/microgram (50,000 revertants/liter of raw gas). Methylnaphthalene, phenanthrene, chrysene, and nitrogen-containing compounds were positively identified in a highly mutagenic fraction of raw gas condensate. While gas cleanup by the humidifier-tar trap system and Venturi scrubber led to only a small reduction in specific mutagenicity of the cooled process stream material (4.1 revertants/microgram), a significant overall reduction in mutagenicity was achieved (to 2200 revertants/liter) due to a substantial reduction in the concentration of material in the gas. By the end of gas cleanup, gas condensates had no detectable mutagenic activity. Condensates of combustion product gas, which contained several polycyclic aromatic compounds, had a specific mutagenicity of 1.1 revertants/microgram (4.0 revertants/liter). Results indicate that the process stream material is potentially toxic and that care should be taken to limit exposure of workers to the condensed tars during gasifier maintenance and repair and to the aerosolized tars emitted in fugitive emissions. Health risks to the general population resulting from exposure to gas combustion products are expected to be minimal.

Fe3O4@MOF core-shell magnetic microspheres as excellent catalysts for the Claisen-Schmidt condensation reaction

NASA Astrophysics Data System (ADS)

Ke, Fei; Qiu, Ling-Guang; Zhu, Junfa

2014-01-01

Separation and recycling of catalysts after catalytic reactions are critically required to reduce the cost of catalysts as well as to avoid the generation of waste in industrial applications. In this work, we present a facile fabrication and characterization of a novel type of MOF-based porous catalyst, namely, Fe3O4@MIL-100(Fe) core-shell magnetic microspheres. It has been shown that these catalysts not only exhibit high catalytic activities for the Claisen-Schmidt condensation reactions under environmentally friendly conditions, but remarkably, they can be easily separated and recycled without significant loss of catalytic efficiency after being used for many times. Therefore, compared to other reported catalysts used in the Claisen-Schmidt condensation reactions, these catalysts are green, cheap and more suitable for large scale industrial applications.Separation and recycling of catalysts after catalytic reactions are critically required to reduce the cost of catalysts as well as to avoid the generation of waste in industrial applications. In this work, we present a facile fabrication and characterization of a novel type of MOF-based porous catalyst, namely, Fe3O4@MIL-100(Fe) core-shell magnetic microspheres. It has been shown that these catalysts not only exhibit high catalytic activities for the Claisen-Schmidt condensation reactions under environmentally friendly conditions, but remarkably, they can be easily separated and recycled without significant loss of catalytic efficiency after being used for many times. Therefore, compared to other reported catalysts used in the Claisen-Schmidt condensation reactions, these catalysts are green, cheap and more suitable for large scale industrial applications. Electronic supplementary information (ESI) available: SEM and TEM images, and GC-MS spectra for chalcones. See DOI: 10.1039/c3nr05051c

GENOTOXICITY OF TEN CIGARETTE SMOKE CONDENSATES IN FOUR TEST SYSTEMS: COMPARISONS BETWEEN ASSAYS AND CONDENSATES

EPA Science Inventory

What is the study?
This the first assessment of a set of cigarette smoke condensates from a range of cigarette types in a variety (4) of short-term genotoxicity assays.
Why was it done?
No such comparative study of cigarette smoke condensates has been reported. H...

Repulsive four-body interactions of α particles and quasistable nuclear α -particle condensates in heavy self-conjugate nuclei

NASA Astrophysics Data System (ADS)

Bai, Dong; Ren, Zhongzhou

2018-05-01

We study the effects of repulsive four-body interactions of α particles on nuclear α -particle condensates in heavy self-conjugate nuclei using a semianalytic approach, and find that the repulsive four-body interactions could decrease the critical number of α particles, beyond which quasistable α -particle condensate states can no longer exist, even if these four-body interactions make only tiny contributions to the total energy of the Hoyle-like state of 16O. Explicitly, we study eight benchmark parameter sets, and find that the critical number Ncr decreases by |Δ Ncr|˜1 -4 from Ncr˜11 with vanishing four-body interactions. We also discuss the effects of four-body interactions on energies and radii of α -particle condensates. Our study can be useful for future experiments to study α -particle condensates in heavy self-conjugate nuclei. Also, the experimental determination of Ncr will eventually help establish a better understanding on the α -particle interactions, especially the four-body interactions.

New Challenges in Computational Thermal Hydraulics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadigaroglu, George; Lakehal, Djamel

New needs and opportunities drive the development of novel computational methods for the design and safety analysis of light water reactors (LWRs). Some new methods are likely to be three dimensional. Coupling is expected between system codes, computational fluid dynamics (CFD) modules, and cascades of computations at scales ranging from the macro- or system scale to the micro- or turbulence scales, with the various levels continuously exchanging information back and forth. The ISP-42/PANDA and the international SETH project provide opportunities for testing applications of single-phase CFD methods to LWR safety problems. Although industrial single-phase CFD applications are commonplace, computational multifluidmore » dynamics is still under development. However, first applications are appearing; the state of the art and its potential uses are discussed. The case study of condensation of steam/air mixtures injected from a downward-facing vent into a pool of water is a perfect illustration of a simulation cascade: At the top of the hierarchy of scales, system behavior can be modeled with a system code; at the central level, the volume-of-fluid method can be applied to predict large-scale bubbling behavior; at the bottom of the cascade, direct-contact condensation can be treated with direct numerical simulation, in which turbulent flow (in both the gas and the liquid), interfacial dynamics, and heat/mass transfer are directly simulated without resorting to models.« less

de Sitter space from dilatino condensates in massive IIA supergravity

NASA Astrophysics Data System (ADS)

Souères, Bertrand; Tsimpis, Dimitrios

2018-02-01

We use the superspace formulation of (massive) IIA supergravity to obtain the explicit form of the dilatino terms, and we find that the quartic-dilatino term is positive. The theory admits a ten-dimensional de Sitter solution, obtained by assuming a nonvanishing quartic-dilatino condensate which generates a positive cosmological constant. Moreover, in the presence of dilatino condensates, the theory admits formal four-dimensional de Sitter solutions of the form d S4×M6, where M6 is a six-dimensional Kähler-Einstein manifold of positive scalar curvature.

Re-evaluating the Localization of Sperm-Retained Histones Revealed the Modification-Dependent Accumulation in Specific Genome Regions.

PubMed

Yamaguchi, Kosuke; Hada, Masashi; Fukuda, Yuko; Inoue, Erina; Makino, Yoshinori; Katou, Yuki; Shirahige, Katsuhiko; Okada, Yuki

2018-06-26

The question of whether retained histones in the sperm genome localize to gene-coding regions or gene deserts has been debated for years. Previous contradictory observations are likely caused by the non-uniform sensitivity of sperm chromatin to micrococcal nuclease (MNase) digestion. Sperm chromatin has a highly condensed but heterogeneous structure and is composed of 90%∼99% protamines and 1%∼10% histones. In this study, we utilized nucleoplasmin (NPM) to improve the solubility of sperm chromatin by removing protamines in vitro. NPM treatment efficiently solubilized histones while maintaining quality and quantity. Chromatin immunoprecipitation sequencing (ChIP-seq) analyses using NPM-treated sperm demonstrated the predominant localization of H4 to distal intergenic regions, whereas modified histones exhibited a modification-dependent preferential enrichment in specific genomic elements, such as H3K4me3 at CpG-rich promoters and H3K9me3 in satellite repeats, respectively, implying the existence of machinery protecting modified histones from eviction. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Design and Fabrication of a Hybrid Superhydrophobic-Hydrophilic Surface That Exhibits Stable Dropwise Condensation.

PubMed

Mondal, Bikash; Mac Giolla Eain, Marc; Xu, QianFeng; Egan, Vanessa M; Punch, Jeff; Lyons, Alan M

2015-10-28

Condensation of water vapor is an essential process in power generation, water collection, and thermal management. Dropwise condensation, where condensed droplets are removed from the surface before coalescing into a film, has been shown to increase the heat transfer efficiency and water collection ability of many surfaces. Numerous efforts have been made to create surfaces which can promote dropwise condensation, including superhydrophobic surfaces on which water droplets are highly mobile. However, the challenge with using such surfaces in condensing environments is that hydrophobic coatings can degrade and/or water droplets on superhydrophobic surfaces transition from the mobile Cassie to the wetted Wenzel state over time and condensation shifts to a less-effective filmwise mechanism. To meet the need for a heat-transfer surface that can maintain stable dropwise condensation, we designed and fabricated a hybrid superhydrophobic-hydrophilic surface. An array of hydrophilic needles, thermally connected to a heat sink, was forced through a robust superhydrophobic polymer film. Condensation occurs preferentially on the needle surface due to differences in wettability and temperature. As the droplet grows, the liquid drop on the needle remains in the Cassie state and does not wet the underlying superhydrophobic surface. The water collection rate on this surface was studied using different surface tilt angles, needle array pitch values, and needle heights. Water condensation rates on the hybrid surface were shown to be 4 times greater than for a planar copper surface and twice as large for silanized silicon or superhydrophobic surfaces without hydrophilic features. A convection-conduction heat transfer model was developed; predicted water condensation rates were in good agreement with experimental observations. This type of hybrid superhydrophobic-hydrophilic surface with a larger array of needles is low-cost, robust, and scalable and so could be used for heat transfer and water collection applications.

Environmental durability diagnostic for printed identification codes of polymer insulation for distribution pipelines

NASA Astrophysics Data System (ADS)

Zhuravleva, G. N.; Nagornova, I. V.; Kondratov, A. P.; Bablyuk, E. B.; Varepo, L. G.

2017-08-01

A research and modelling of weatherability and environmental durability of multilayer polymer insulation of both cable and pipelines with printed barcodes or color identification information were performed. It was proved that interlayer printing of identification codes in distribution pipelines insulation coatings provides high marking stability to light and atmospheric condensation. This allows to carry out their distant damage control. However, microbiological fouling of upper polymer layer hampers the distant damage pipelines identification. The color difference values and density changes of PE and PVC printed insolation due to weather and biological factors were defined.

GW/Bethe-Salpeter calculations for charged and model systems from real-space DFT

NASA Astrophysics Data System (ADS)

Strubbe, David A.

GW and Bethe-Salpeter (GW/BSE) calculations use mean-field input from density-functional theory (DFT) calculations to compute excited states of a condensed-matter system. Many parts of a GW/BSE calculation are efficiently performed in a plane-wave basis, and extensive effort has gone into optimizing and parallelizing plane-wave GW/BSE codes for large-scale computations. Most straightforwardly, plane-wave DFT can be used as a starting point, but real-space DFT is also an attractive starting point: it is systematically convergeable like plane waves, can take advantage of efficient domain parallelization for large systems, and is well suited physically for finite and especially charged systems. The flexibility of a real-space grid also allows convenient calculations on non-atomic model systems. I will discuss the interfacing of a real-space (TD)DFT code (Octopus, www.tddft.org/programs/octopus) with a plane-wave GW/BSE code (BerkeleyGW, www.berkeleygw.org), consider performance issues and accuracy, and present some applications to simple and paradigmatic systems that illuminate fundamental properties of these approximations in many-body perturbation theory.

Flexible and Comprehensive Implementation of MD-PMM Approach in a General and Robust Code.

PubMed

Carrillo-Parramon, Oliver; Del Galdo, Sara; Aschi, Massimiliano; Mancini, Giordano; Amadei, Andrea; Barone, Vincenzo

2017-11-14

The Perturbed Matrix Method (PMM) approach to be used in combination with Molecular Dynamics (MD) trajectories (MD-PMM) has been recoded from scratch, improved in several aspects, and implemented in the Gaussian suite of programs for allowing a user-friendly and yet flexible tool to estimate quantum chemistry observables in complex systems in condensed phases. Particular attention has been devoted to a description of rigid and flexible quantum centers together with powerful essential dynamics and clustering approaches. The default implementation is fully black-box and does not require any external action concerning both MD and PMM sections. At the same time, fine-tuning of different parameters and use of external data are allowed in all the steps of the procedure. Two specific systems (Tyrosine and Uridine) have been reinvestigated with the new version of the code in order to validate the implementation, check the performances, and illustrate some new features.

Probabilistic boundary element method

NASA Technical Reports Server (NTRS)

Cruse, T. A.; Raveendra, S. T.

1989-01-01

The purpose of the Probabilistic Structural Analysis Method (PSAM) project is to develop structural analysis capabilities for the design analysis of advanced space propulsion system hardware. The boundary element method (BEM) is used as the basis of the Probabilistic Advanced Analysis Methods (PADAM) which is discussed. The probabilistic BEM code (PBEM) is used to obtain the structural response and sensitivity results to a set of random variables. As such, PBEM performs analogous to other structural analysis codes such as finite elements in the PSAM system. For linear problems, unlike the finite element method (FEM), the BEM governing equations are written at the boundary of the body only, thus, the method eliminates the need to model the volume of the body. However, for general body force problems, a direct condensation of the governing equations to the boundary of the body is not possible and therefore volume modeling is generally required.

NLSEmagic: Nonlinear Schrödinger equation multi-dimensional Matlab-based GPU-accelerated integrators using compact high-order schemes

NASA Astrophysics Data System (ADS)

Caplan, R. M.

2013-04-01

We present a simple to use, yet powerful code package called NLSEmagic to numerically integrate the nonlinear Schrödinger equation in one, two, and three dimensions. NLSEmagic is a high-order finite-difference code package which utilizes graphic processing unit (GPU) parallel architectures. The codes running on the GPU are many times faster than their serial counterparts, and are much cheaper to run than on standard parallel clusters. The codes are developed with usability and portability in mind, and therefore are written to interface with MATLAB utilizing custom GPU-enabled C codes with the MEX-compiler interface. The packages are freely distributed, including user manuals and set-up files. Catalogue identifier: AEOJ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOJ_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 124453 No. of bytes in distributed program, including test data, etc.: 4728604 Distribution format: tar.gz Programming language: C, CUDA, MATLAB. Computer: PC, MAC. Operating system: Windows, MacOS, Linux. Has the code been vectorized or parallelized?: Yes. Number of processors used: Single CPU, number of GPU processors dependent on chosen GPU card (max is currently 3072 cores on GeForce GTX 690). Supplementary material: Setup guide, Installation guide. RAM: Highly dependent on dimensionality and grid size. For typical medium-large problem size in three dimensions, 4GB is sufficient. Keywords: Nonlinear Schröodinger Equation, GPU, high-order finite difference, Bose-Einstien condensates. Classification: 4.3, 7.7. Nature of problem: Integrate solutions of the time-dependent one-, two-, and three-dimensional cubic nonlinear Schrödinger equation. Solution method: The integrators utilize a fully-explicit fourth-order Runge-Kutta scheme in time and both second- and fourth-order differencing in space. The integrators are written to run on NVIDIA GPUs and are interfaced with MATLAB including built-in visualization and analysis tools. Restrictions: The main restriction for the GPU integrators is the amount of RAM on the GPU as the code is currently only designed for running on a single GPU. Unusual features: Ability to visualize real-time simulations through the interaction of MATLAB and the compiled GPU integrators. Additional comments: Setup guide and Installation guide provided. Program has a dedicated web site at www.nlsemagic.com. Running time: A three-dimensional run with a grid dimension of 87×87×203 for 3360 time steps (100 non-dimensional time units) takes about one and a half minutes on a GeForce GTX 580 GPU card.

WARM-LIQUID DEFROST FOR COMMERCIAL FOOD DISPLAY CASES: EXPERIMENTAL INVESTIGATION AT 32.2 DEGREES C CONDENSING

EPA Science Inventory

The paper gives results of an experimental investigation at 32.2 C condensing of warm-liquid defrost for commercial food display cases. A refrigeration test rig with two open cases and two reach-in cases was tested using warm-liquid defrost (WLD) at -34.4 C evaporating, 32.2 C co...

A global three-dimensional model of the stratospheric sulfuric acid layer

NASA Technical Reports Server (NTRS)

Golombek, Amram; Prinn, Ronald G.

1993-01-01

A 3D model which encompasses SO2 production from OCS, followed by its oxidation to gaseous H2SO4, the condensation-evaporation equilibrium of gaseous and particulate H2SO4, and finally particle condensation and rainout, is presently used to study processes maintaining the nonvolcanically-perturbed stratosphere's sulfuric acid layer. A comparison of the results thus obtained with remotely sensed stratospheric aerosol extinction data shows the model to simulate the general behavior of stratospheric aerosol extinction.

Iron(II) supramolecular helicates condense plasmid DNA and inhibit vital DNA-related enzymatic activities.

PubMed

Malina, Jaroslav; Hannon, Michael J; Brabec, Viktor

2015-07-27

The dinuclear iron(II) supramolecular helicates [Fe2 L3 ]Cl4 (L=C25 H20 N4 ) bind to DNA through noncovalent (i.e., hydrogen-bonding, electrostatic) interactions and exhibit antimicrobial and anticancer effects. In this study, we show that the helicates condense plasmid DNA with a much higher potency than conventional DNA-condensing agents. Notably, molecules of DNA in the presence of the M enantiomer of [Fe2 L3 ]Cl4 do not form intermolecular aggregates typically formed by other condensing agents, such as spermidine or spermine. The helicates inhibit the activity of several DNA-processing enzymes, such as RNA polymerase, DNA topoisomerase I, deoxyribonuclease I, and site-specific restriction endonucleases. However, the results also indicate that the DNA condensation induced by the helicates does not play a crucial role in these inhibition reactions. The mechanisms for the inhibitory effects of [Fe2 L3 ]Cl4 helicates on DNA-related enzymatic activities have been proposed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Boehmite-An Efficient and Recyclable Acid-Base Bifunctional Catalyst for Aldol Condensation Reaction.

PubMed

Reshma, P C Rajan; Vikneshvaran, Sekar; Velmathi, Sivan

2018-06-01

In this work boehmite was used as an acid-base bifunctional catalyst for aldol condensation reactions of aromatic aldehydes and ketones. The catalyst was prepared by simple sol-gel method using Al(NO3)3·9H2O and NH4OH as precursors. The catalyst has been characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), UV-visible spectroscopy (DRS), BET surface area analyses. Boehmite is successfully applied as catalyst for the condensation reaction between 4-nitrobenzaldehyde and acetone as a model substrate giving α, β-unsaturated ketones without any side product. The scope of the reaction is extended for various substituted aldehydes. A probable mechanism has been suggested to explain the cooperative behavior of the acidic and basic sites. The catalyst is environmentally friendly and easily recovered from the reaction mixture. Also the catalyst is reusable up to 3 catalytic cycles.

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins.

Code of Federal Regulations, 2010 CFR

2010-04-01

...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION... Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins. The...′-isopropylidenediphenol-epichlorohydrin epoxy resins, to which may have been added certain optional adjuvant substances...

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins.

Code of Federal Regulations, 2011 CFR

2011-04-01

...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION... Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins. The...′-isopropylidenediphenol-epichlorohydrin epoxy resins, to which may have been added certain optional adjuvant substances...

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins.

Code of Federal Regulations, 2012 CFR

2012-04-01

...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION... Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins. The...′-isopropylidenediphenol-epichlorohydrin epoxy resins, to which may have been added certain optional adjuvant substances...

21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins.

Code of Federal Regulations, 2013 CFR

2013-04-01

...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION... Xylene-formaldehyde resins condensed with 4,4′-isopropylidenediphenol-epichlorohydrin epoxy resins. The...′-isopropylidenediphenol-epichlorohydrin epoxy resins, to which may have been added certain optional adjuvant substances...

AN EXPERIMENTAL STUDY ON ARTIFICIAL CONDENSATION NUCLEI,

DTIC Science & Technology

NH4Cl, CaCl2, P205, NH4NO3, (NH4)2SO4, etc.) and suspensoids such as camphor , silicon minerals, kaolin, lamp black, and calcium lime (CaO). The...findings reveal that the above mentioned soluble nuclei and camphor powder are active artificial hygroscopic condensation nuclei and that lamp black

interThermalPhaseChangeFoam-A framework for two-phase flow simulations with thermally driven phase change

NASA Astrophysics Data System (ADS)

Nabil, Mahdi; Rattner, Alexander S.

The volume-of-fluid (VOF) approach is a mature technique for simulating two-phase flows. However, VOF simulation of phase-change heat transfer is still in its infancy. Multiple closure formulations have been proposed in the literature, each suited to different applications. While these have enabled significant research advances, few implementations are publicly available, actively maintained, or inter-operable. Here, a VOF solver is presented (interThermalPhaseChangeFoam), which incorporates an extensible framework for phase-change heat transfer modeling, enabling simulation of diverse phenomena in a single environment. The solver employs object oriented OpenFOAM library features, including Run-Time-Type-Identification to enable rapid implementation and run-time selection of phase change and surface tension force models. The solver is packaged with multiple phase change and surface tension closure models, adapted and refined from earlier studies. This code has previously been applied to study wavy film condensation, Taylor flow evaporation, nucleate boiling, and dropwise condensation. Tutorial cases are provided for simulation of horizontal film condensation, smooth and wavy falling film condensation, nucleate boiling, and bubble condensation. Validation and grid sensitivity studies, interfacial transport models, effects of spurious currents from surface tension models, effects of artificial heat transfer due to numerical factors, and parallel scaling performance are described in detail in the Supplemental Material (see Appendix A). By incorporating the framework and demonstration cases into a single environment, users can rapidly apply the solver to study phase-change processes of interest.

Localization of the 5S and 45S rDNA Sites and cpDNA Sequence Analysis in Species of the Quadrifaria Group of Paspalum (Poaceae, Paniceae)

PubMed Central

VAIO, MAGDALENA; SPERANZA, PABLO; VALLS, JOSÉ FRANCISCO; GUERRA, MARCELO; MAZZELLA, CRISTINA

2005-01-01

• Background and Aims The Quadrifaria group of Paspalum (Poaceae, Paniceae) comprises species native to the subtropical and temperate regions of South America. The purpose of this research was to characterize the I genomes in five species of this group and to establish phylogenetic relationships among them. • Methods Prometaphase chromatin condensation patterns, the physical location of 5S and 45S rDNA sites by fluorescence in situ hybridization (FISH), and sequences of five chloroplast non-coding regions were analysed. • Key Results The condensation patterns observed were highly conserved among diploid and tetraploid accessions studied and not influenced by the dyes used or by the FISH procedure, allowing the identification of almost all the chromosome pairs that carried the rDNA signals. The FISH analysis of 5S rDNA sites showed the same localization and a correspondence between the number of sites and ploidy level. In contrast, the distribution of 45S rDNA sites was variable. Two general patterns were observed with respect to the location of the 45S rDNA. The species and cytotypes Paspalum haumanii 2x, P. intermedium 2x, P. quadrifarium 4x and P. exaltatum 4x showed proximal sites on chromosome 8 and two to four distal sites in other chromosomes, while P. quarinii 4x and P. quadrifarium 2x showed only distal sites located on a variable number of small chromosomes and on the long arm of chromosome 1. The single most-parsimonious tree found from the phylogenetic analysis showed the Quadrifaria species partitioned in two clades, one of them includes P. haumanii 2x and P. intermedium 2x together with P. quadrifarium 4x and P. exaltatum 4x, while the other contains P. quadrifarium 2x and P. quarinii 4x. • Conclusions The subdivision found with FISH is consistent with the clades recovered with cpDNA data and both analyses suggest that the Quadrifaria group, as presently defined, is not monophyletic and its species belong in at least two clades. PMID:15911540

Gravitationally Unstable Condensations Revealed by ALMA in the TUKH122 Prestellar Core in the Orion A Cloud

NASA Astrophysics Data System (ADS)

Ohashi, Satoshi; Sanhueza, Patricio; Sakai, Nami; Kandori, Ryo; Choi, Minho; Hirota, Tomoya; Nguyễn-Lu’o’ng, Quang; Tatematsu, Ken’ichi

2018-04-01

We have investigated the TUKH122 prestellar core in the Orion A cloud using ALMA 3 mm dust continuum, N2H+ (J = 1‑0), and CH3OH ({J}K={2}K-{1}K) molecular-line observations. Previous studies showed that TUKH122 is likely on the verge of star formation because the turbulence is almost dissipated and chemically evolved among other starless cores in the Orion A cloud. By combining ALMA 12 m and ACA data, we recover extended emission with a resolution of ∼5″ corresponding to 0.01 pc and identify six condensations with a mass range of 0.1–0.4 M ⊙ and a radius of ≲0.01 pc. These condensations are gravitationally bound following a virial analysis and are embedded in the filament, including the elongated core with a mass of ∼29 M ⊙ and a radial density profile of r ‑1.6 derived by Herschel. The separation of these condensations is ∼0.035 pc, consistent with the thermal Jeans length at a density of 4.4 × 105 cm‑3. This density is similar to the central part of the core. We also find a tendency for the N2H+ molecule to deplete at the dust peak condensation. This condensation may be beginning to collapse because the line width becomes broader. Therefore, the fragmentation still occurs in the prestellar core by thermal Jeans instability, and multiple stars are formed within the TUKH122 prestellar core. The CH3OH emission shows a large shell-like distribution and surrounds these condensations, suggesting that the CH3OH molecule formed on dust grains is released into the gas phase by nonthermal desorption such as photoevaporation caused by cosmic-ray-induced UV radiation.

Experimental study of the condensation heat transfer characteristics of CO2 in a horizontal microfin tube with a diameter of 4.95 mm

NASA Astrophysics Data System (ADS)

Son, Chang-Hyo; Oh, Hoo-Kyu

2012-11-01

The condensation heat transfer characteristics for CO2 flowing in a horizontal microfin tube were investigated by experiment with respect to condensation temperature and mass flux. The test section consists of a 2,400 mm long horizontal copper tube of 4.6 mm inner diameter. The experiments were conducted at refrigerant mass flux of 400-800 kg/m2s, and saturation temperature of 20-30 °C. The main experimental results showed that annular flow was highly dominated the majority of condensation flow in the horizontal microfin tube. The condensation heat transfer coefficient increases with decreasing saturation temperature and increasing mass flux. The experimental data were compared against previous heat transfer correlations. Most correlations failed to predict the experimental data. However, the correlation by Cavallini et al. showed relatively good agreement with experimental data in the microfin tube. Therefore, a new condensation heat transfer correlation is proposed with mean and average deviations of 3.14 and -7.6 %, respectively.

HPLC, NMR and MALDI-TOF MS analysis of condensed tannins from Lithocarpus glaber leaves with potent free radical scavenging activity.

PubMed

Zhang, Liang Liang; Lin, Yi Ming

2008-12-04

Using acid-catalyzed degradation in the presence of cysteamine, the condensed tannins from Lithocarpus glaber leaves were characterized, following thiolysis, by means of reversed-phase HPLC, 13C-NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analyses. The thiolysis reaction products showed the presence of the procyanidin (PC) and prodelphinidin (PD) structures. The 13C-NMR spectrum revealed that the condensed tannins were comprised of PD (72.4%) and PC (27.6%), and with a greater content of cis configuration rather than the trans configuration of C2-C3. The MALDI-TOF MS analysis proved the presence of PD units, and the maximum degree of polymerization (DP) was an undecamer. The antioxidant activity of condensed tannins from L. glaber leaves was evaluated by using a free radical scavenging activity assay.

Effects of various reactive gas atmospheres on the properties of bio-oil using microwave pyrolysis

USDA-ARS?s Scientific Manuscript database

Fast pyrolysis of lignocellulosic biomass produces organic liquids (bio-oil), bio-char, water, and non-condensable gases. The non-condensable gas component typically contains syngas (H2, CO and CO2) as well as small hydrocarbons (CH4, C2H6, and C3H8). Tail Gas Reactive Pyrolysis (TGRP), a patent p...

Photoinduced Processes in Cobalt-Complexes: Condensed Phase and Gas Phase

NASA Astrophysics Data System (ADS)

Rupp, F.; Chevalier, K.; Wolf, M. M. N.; Krüger, H.-J.; Wüllen, C. v.; Nosenko, Y.; Niedner-Schatteburg, Y.; Riehn, C.; Diller, R.

2013-03-01

Femtosecond time-resolved, steady-state spectroscopic methods and quantum chemical calculations are employed to study ultrafast photoinduced processes in [Co(III)-(L-N4Me2)(dbc)](BPh4) and [Co(II)-(L-N4tBu2)(dbsq)](B(p-C6H4Cl)4) and to characterise the transient redox- and spin-states in condensed and gas phase.

The Features of Condensate Water and Its Guide on Gas Proudction in upper Triassic Gas Reservoir of Western Sichuan Depression, China

NASA Astrophysics Data System (ADS)

Shang, C.; Lou, Z.

2012-12-01

In upper Triassic Xujiahe Formation of western Sichuan depression, China, there developed ultrathight sandstones reservoirs, of which the mean porosity is 4.02% and the permeability mode is less than 0.1×10-3μm2. Because of the ultrathight sandstones, thick gaseous- liquid phase transition develops in the upper Trassic Xujiahe Formation. The absolute quantity of gaseous water is lager. Due to the change of temperature and pressure at the wellhead, the gaseous water in gas reservoir becomes condensate water. Therefore, the condensate water of low salinity can be widely found at the original productive process in the Xujiahe Formation reservoir, such as wells named Lian 150, Xin 851, Xin 853, Xin 856, Dayi 101, Dayi 103. The main cations are K++Na+, while the anions are HCO3- and Cl-. The main water type is CaCl2, followed by NaHCO3, Na2SO4 and MgCl2. The PH of condensate water is 5.28-8.20 with mean value 6.40. The salinity of condensate water is lower than that of formation water. The milligram equivalent (mEq) percent of ion is used to study the features of condensate water. The anions (mEq) distribution of condensate water are scattered in ternary diagram, while that of formation water concentrate upon the SO42- and Cl- endpoints. The percent of HCO3-(mEq) in condensate water is higher than that of formation water. There is no obvious difference of cations mEq percent between condensate water and formation water, which indicates that condensate water strongly affected by formation water. Through this study, condensate water may originate from formation water and then be affected by complicated physical and chemical interactions. The condensate water is affected by gas and formation water. The relationship between condensate water and gas yield is very close. The variations of water yield, salinity and ions composition can reflect the change of gas yield. Taking well Xin 856 for example, which is located in Xinchang gas felid, there exist a relationship between the condensate water yield and the gas yield. The sequence of high- medial -low gas yield is in consistent with the variation of condensate water - mixture water- formation water, in well Xin 856. In addition, water-gas ratio increases gradually from 0.049 m3/104m3 to 258.54 m3/104m3, in the whole process. Based on water yield of well Xin 856, the transition from condensate water to formation water can be indicated by the increase of salinity and the decrease of mEq percent of HCO3-. The percent of ions (mEq) of condensate water and formation water in Xujiahe formation gas reservoir of western Sichuan depression. a the percent of cations (mEq); b the percent of anions (mEq)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, David L.; Schoof, Justin C.; Hobbs, Michael L.

This report presents plots of specific heat, enthalpy, entropy, and Gibbs free energy for 1439 species in the JCZS2i database. Included in this set of species are 496 condensed-phase species and 943 gas-phase species. The gas phase species contain 80 anions and 112 cations for a total of 192 ions. The JCZS2i database is used in conjunction with the TIGER thermochemical code to predict thermodynamic states from ambient conditions to high temperatures and pressures. Predictions from the TIGER code using the JCZS2i database can be used in shock physics codes where temperatures may be as high as 20,000 K andmore » ions may be present. Such high temperatures were not considered in the original JCZS database, and extrapolations made for these temperatures were unrealistic. For example, specific heat would sometimes go negative at high temperatures which fails the definition of specific heat. The JCZS2i database is a new version of the JCZS database that is being created to address these inaccuracies. The purpose of the current report is to visualize the high temperature extrapolations to insure that the specific heat, enthalpy, entropy, and Gibbs free energy predictions are reasonable up to 20,000 K.« less

Experimental investigation of condensation predictions for dust-enriched systems

NASA Astrophysics Data System (ADS)

Ustunisik, Gokce; Ebel, Denton S.; Walker, David; Boesenberg, Joseph S.

2014-10-01

Condensation models describe the equilibrium distribution of elements between coexisting phases (mineral solid solutions, silicate liquid, and vapor) in a closed chemical system, where the vapor phase is always present, using equations of state of the phases involved at a fixed total pressure (<1 bar) and temperature (T). The VAPORS code uses a CaO-MgO-Al2O3-SiO2 (CMAS) liquid model at T above the stability field of olivine, and the MELTS thermodynamics algorithm at lower T. Quenched high-T crystal + liquid assemblages are preserved in meteorites as Type B Ca-, Al-rich inclusions (CAIs), and olivine-rich ferromagnesian chondrules. Experimental tests of compositional regions within 100 K of the predicted T of olivine stability may clarify the nature of the phases present, the phase boundaries, and the partition of trace elements among these phases. Twenty-three Pt-loop equilibrium experiments in seven phase fields on twelve bulk compositions at specific T and dust enrichment factors tested the predicted stability fields of forsteritic olivine (Mg2SiO4), enstatite (MgSiO3), Cr-bearing spinel (MgAl2O4), perovskite (CaTiO3), melilite (Ca2Al2SiO7-Ca2Mg2Si2O7) and/or grossite (CaAl4O7) crystallizing from liquid. Experimental results for forsterite, enstatite, and grossite are in very good agreement with predictions, both in chemistry and phase abundances. On the other hand the stability of spinel with olivine, and stability of perovskite and gehlenite are quite different from predictions. Perovskite is absent in all experiments. Even at low oxygen fugacity (IW-3.4), the most TiO2-rich experiments do not crystallize Al-, Ti-bearing calcic pyroxene. The stability of spinel and olivine together is limited to a smaller phase field than is predicted. The melilite stability field is much larger than predicted, indicating a deficiency of current liquid or melilite activity models. In that respect, these experiments contribute to improving the data for calibrating thermodynamic models including MELTS.

Transformation of Litchi Pericarp-Derived Condensed Tannin with Aspergillus awamori.

PubMed

Lin, Sen; Li, Qing; Yang, Bao; Duan, Xuewu; Zhang, Mingwei; Shi, John; Jiang, Yueming

2016-07-12

Condensed tannin is a ubiquitous polyphenol in plants that possesses substantial antioxidant capacity. In this study, we have investigated the polyphenol extraction recovery and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of the extracted polyphenol after litchi pericarp is treated with Aspergillus awamori, Aspergillus sojae or Aspergillus oryzae. We have further explored the activity of A. awamori in the formation of condensed tannin. The treatment of A. awamori appeared to produce the highest antioxidant activity of polyphenol from litchi pericarp. Further studies suggested that the treatment of A. awamori releases the non-extractable condensed tannin from cell walls of litchi pericarp. The total extractable tannin in the litchi pericarp residue after a six-time extraction with 60% ethanol increased from 199.92 ± 14.47-318.38 ± 7.59 μg/g dry weight (DW) after the treatment of A. awamori. The ESI-TOF-MS and HPLC-MS² analyses further revealed that treatment of A. awamori degraded B-type condensed tannin (condensed flavan-3-ol via C4-C8 linkage), but exhibited a limited capacity to degrade the condensed tannin containing A-type linkage subunits (C4-C8 coupled C2-O-C7 linkage). These results suggest that the treatment of A. awamori can significantly improve the production of condensed tannin from litchi pericarp.

Iron-catalyzed vinylogous aldol condensation of Biginelli products and its application toward pyrido[4,3-d]pyrimidinones.

PubMed

Zhang, Lianqiang; Zhang, Zhiguo; Liu, Qingfeng; Liu, Tongxin; Zhang, Guisheng

2014-03-07

A novel iron-catalyzed vinylogous aldol condensation of Biginelli products with aryl aldehydes has been developed for the syntheses of potential bioactive (E)-6-arylvinyl-dihydropyrimidin-2(1H)-ones. These materials are valuable synthetic precursors to drug-like pyrido[4,3-d]pyrimidine derivatives. The amide group at the 5-position of the dihydropyrimidin-2(1H)-ones played an important role in the vinylogous aldol condensation reaction.

Optical tweezers reveal force plateau and internal friction in PEG-induced DNA condensation.

PubMed

Ojala, Heikki; Ziedaite, Gabija; Wallin, Anders E; Bamford, Dennis H; Hæggström, Edward

2014-03-01

The simplified artificial environments in which highly complex biological systems are studied do not represent the crowded, dense, salty, and dynamic environment inside the living cell. Consequently, it is important to investigate the effect of crowding agents on DNA. We used a dual-trap optical tweezers instrument to perform force spectroscopy experiments at pull speeds ranging from 0.3 to 270 μm/s on single dsDNA molecules in the presence of poly(ethylene glycol) (PEG) and monovalent salt. PEG of sizes 1,500 and 4,000 Da condensed DNA, and force-extension data contained a force plateau at approximately 1 pN. The level of the force plateau increased with increasing pull speed. During slow pulling the dissipated work increased linearly with pull speed. The calculated friction coefficient did not depend on amount of DNA incorporated in the condensate, indicating internal friction is independent of the condensate size. PEG300 had no effect on the dsDNA force-extension curve. The force plateau implies that condensation induced by crowding agents resembles condensation induced by multivalent cations.

Degradation of trans-polyisoprene after root filling with thermoplasticized techniques.

PubMed

Maniglia-Ferreira, C; Bönecker, G; Silva, J B A; de Paula, R C M; Feitosa, J P A; Souza-Filho, F J

2008-04-01

To evaluate ex vivo degradation of gutta-percha following six thermoplastic obturation techniques. Ninety human-extracted mandibular premolars were selected and divided randomly into nine groups for filling. Group 1: thermomechanical compaction for 3 s with Konne gutta-percha points (Konne Ind. e Com. de Mat. Odontol., Belo Horizonte, MG, Brazil); Group 2: thermomechanical compaction for 3 s with Dentsply TP gutta-percha points (Dentsply Indústria e Comércio Ltda, Petrópolis, R.J. Brazil); Group 3: thermomechanical compaction for 10 s with Konne; Group 4: thermomechanical compaction for 10 s with Dentsply TP; Group 5: warm vertical condensation using System B (EIE/Analytic, Richmond, WA, USA) with Konne; Group 6: warm vertical condensation using System B with Dentsply TP; Group 7: vertical condensation with Konne; Group 8: vertical condensation with Dentsply TP; Group 9: Microseal cone (Analytic Endodontics, Glendora, CA, USA). A further four groups were assessed without using teeth, Group 10: Microseal microflow (Analytic Endodontics); Group 11: Obtura (Obtura Corporation, Penton, MO, USA); Group 12: Obtura flow (Obtura Corporation); Group 13: Thermafil (Dentsply Maillefer, Tulsa, OK, USA). The filling material was removed from the root canal and trans-1,4-polyisoprene isolated by solubilization of the root filling remnants in chloroform followed by filtration and centrifugation. By gel permeation chromatography and infrared spectroscopy, the occurrence and degree of degradation were assessed. The results were analysed statistically using the Kruskal-Wallis test. With differential scanning calorimetry, the thermal behaviour of the gutta-percha was determined. A significant decrease in polymer molar mass and the production of carboxyl and hydroxyl groups in the polymer were observed with thermomechanical compaction used for 10 s and vertical condensation filling techniques (P = 0.0001 and P = 0.0005, respectively). Other techniques caused no polymer degradation. Polyisoprene degrades with high temperature. Thermomechanical compaction for 10 s and vertical condensation were associated with the greatest degradative process.

Specific heat measurement set-up for quench condensed thin superconducting films.

PubMed

Poran, Shachaf; Molina-Ruiz, Manel; Gérardin, Anne; Frydman, Aviad; Bourgeois, Olivier

2014-05-01

We present a set-up designed for the measurement of specific heat of very thin or ultra-thin quench condensed superconducting films. In an ultra-high vacuum chamber, materials of interest can be thermally evaporated directly on a silicon membrane regulated in temperature from 1.4 K to 10 K. On this membrane, a heater and a thermometer are lithographically fabricated, allowing the measurement of heat capacity of the quench condensed layers. This apparatus permits the simultaneous thermal and electrical characterization of successively deposited layers in situ without exposing the deposited materials to room temperature or atmospheric conditions, both being irreversibly harmful to the samples. This system can be used to study specific heat signatures of phase transitions through the superconductor to insulator transition of quench condensed films.

Non-equilibrium Transport in Carbon based Adsorbate Systems

NASA Astrophysics Data System (ADS)

Fürst, Joachim; Brandbyge, Mads; Stokbro, Kurt; Jauho, Antti-Pekka

2007-03-01

We have used the Atomistix Tool Kit(ATK) and TranSIESTA[1] packages to investigate adsorption of iron atoms on a graphene sheet. The technique of both codes is based on density functional theory using local basis sets[2], and non-equilibrium Green's functions (NEGF) to calculate the charge distribution under external bias. Spin dependent electronic structure calculations are performed for different iron coverages. These reveal adsorption site dependent charge transfer from iron to graphene leading to screening effects. Transport calculations show spin dependent scattering of the transmission which is analysed obtaining the transmission eigenchannels for each spin type. The phenomena of electromigration of iron in these systems at finite bias will be discussed, estimating the so-called wind force from the reflection[3]. [1] M. Brandbyge, J.-L. Mozos, P. Ordejon, J. Taylor, and K. Stokbro. Physical Review B (Condensed Matter and Materials Physics), 65(16):165401/11-7, 2002. [2] Jose M. Soler, Emilio Artacho, Julian D. Gale, Alberto Garcia, Javier Junquera, Pablo Ordejon, and Daniel Sanchez-Portal. Journal of Physics Condensed Matter, 14(11):2745-2779, 2002. [3] Sorbello. Theory of electromigration. Solid State Physics, 1997.

The Metropolis Monte Carlo method with CUDA enabled Graphic Processing Units

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hall, Clifford; School of Physics, Astronomy, and Computational Sciences, George Mason University, 4400 University Dr., Fairfax, VA 22030; Ji, Weixiao

2014-02-01

We present a CPU–GPU system for runtime acceleration of large molecular simulations using GPU computation and memory swaps. The memory architecture of the GPU can be used both as container for simulation data stored on the graphics card and as floating-point code target, providing an effective means for the manipulation of atomistic or molecular data on the GPU. To fully take advantage of this mechanism, efficient GPU realizations of algorithms used to perform atomistic and molecular simulations are essential. Our system implements a versatile molecular engine, including inter-molecule interactions and orientational variables for performing the Metropolis Monte Carlo (MMC) algorithm,more » which is one type of Markov chain Monte Carlo. By combining memory objects with floating-point code fragments we have implemented an MMC parallel engine that entirely avoids the communication time of molecular data at runtime. Our runtime acceleration system is a forerunner of a new class of CPU–GPU algorithms exploiting memory concepts combined with threading for avoiding bus bandwidth and communication. The testbed molecular system used here is a condensed phase system of oligopyrrole chains. A benchmark shows a size scaling speedup of 60 for systems with 210,000 pyrrole monomers. Our implementation can easily be combined with MPI to connect in parallel several CPU–GPU duets. -- Highlights: •We parallelize the Metropolis Monte Carlo (MMC) algorithm on one CPU—GPU duet. •The Adaptive Tempering Monte Carlo employs MMC and profits from this CPU—GPU implementation. •Our benchmark shows a size scaling-up speedup of 62 for systems with 225,000 particles. •The testbed involves a polymeric system of oligopyrroles in the condensed phase. •The CPU—GPU parallelization includes dipole—dipole and Mie—Jones classic potentials.« less

One-dimensional thermohydraulic code THESEUS and its application to chilldown process simulation in two-phase hydrogen flows

NASA Astrophysics Data System (ADS)

Papadimitriou, P.; Skorek, T.

THESUS is a thermohydraulic code for the calculation of steady state and transient processes of two-phase cryogenic flows. The physical model is based on four conservation equations with separate liquid and gas phase mass conservation equations. The thermohydraulic non-equilibrium is calculated by means of evaporation and condensation models. The mechanical non-equilibrium is modeled by a full-range drift-flux model. Also heat conduction in solid structures and heat exchange for the full spectrum of heat transfer regimes can be simulated. Test analyses of two-channel chilldown experiments and comparisons with the measured data have been performed.

Particle Size of CO2 Condensates in Mars Atmosphere Revealed by Climate Sounder and Laser Ranging Observations

NASA Astrophysics Data System (ADS)

Hu, Renyu

Current-generation Mars Climate Sounder (MCS) onboard the Mars Reconnaissance Orbiter (MRO) offers extensive coverage of the latitudinal and seasonal distribution of CO_2 condensation in Mars’s atmosphere. The atmospheric temperature profiles measured by MCS reveal that the thickness of CO_2 condensation layer reaches a maximum of 10-15 km (north) or ˜20 km (south) during the middle of winter. There is a shrinking of the CO_2 condensation layer from L_S ˜270(°) to ˜300(°) in 2007, probably related to a planet-encircling dust storm. We integrate the condensation area and the condensation occurrence rate synthesized from the MCS observations to estimate cumulative masses of CO2 condensates deposited onto the northern and southern seasonal polar caps. The mass loading of CO_2 condensate particles, when condensation occurs, can be independently inferred from the detections of reflective clouds by the Mars Orbiter Laser Altimetry (MOLA) onboard the Mars Global Surveyor (MGS). Therefore, we approximate the precipitation flux by the particle settling flux, which is estimated using the impulse responses of MOLA filter channels. With our approach, the total atmospheric condensation mass can be estimated from these observational data sets, with average particle size as the only free parameter. By comparison with the seasonal polar cap masses inferred from the time-varying gravity of Mars, our estimates indicate that the average condensate particle radius is 8 - 22 mum in the northern hemisphere and 4 - 13 mum in the southern hemisphere. This multi-instrument data analysis provides new constraints on modeling the microphysics of CO_2 clouds on Mars.

Dual-species Bose-Einstein condensate of {sup 87}Rb and {sup 133}Cs

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCarron, D. J.; Cho, H. W.; Jenkin, D. L.

2011-07-15

We report the formation of a dual-species Bose-Einstein condensate of {sup 87}Rb and {sup 133}Cs in the same trapping potential. Our method exploits the efficient sympathetic cooling of {sup 133}Cs via elastic collisions with {sup 87}Rb, initially in a magnetic quadrupole trap and subsequently in a levitated optical trap. The two condensates each contain up to 2x10{sup 4} atoms and exhibit a striking phase separation, revealing the mixture to be immiscible due to strong repulsive interspecies interactions. Sacrificing all the {sup 87}Rb during the cooling, we create single-species {sup 133}Cs condensates of up to 6x10{sup 4} atoms.

Mixed messages: An evaluation of NHS Trust Social Media policies in the North West of England.

PubMed

Scragg, B; Shaikh, S; Robinson, L; Mercer, C

2017-08-01

Despite National Health Service (NHS) information strategy promoting the use of Social Media (SoMe) to encourage greater engagement between service users and providers, a team investigating online SoMe interaction between breast screening practitioners and clients found that practitioners alleged discouragement from employers' policies. This study aimed to investigate whether this barrier was genuine, and illuminate whether local policy differed from national strategy. The study used a qualitative grounded theory approach to generate a theory. Nine policies from the North West of England were analysed. A framework was derived from the data, and an analysis of policy tone followed by a detailed coding of policy content was undertaken. Comparative analysis continued by reviewing the literature, and a condensed framework revealed five broad categories that policies addressed. The analysis revealed the policies varied in content, but not in tone, which was mostly discouraging. Coding the content revealed that the most frequently addressed point was that of protecting the employers' reputation, and after further analysis, the resultant condensed framework showed that policies were imbalanced and heavily skewed towards Security, Conduct & Behaviour and Reputation. Practitioners within breast screening services are discouraged by overly prohibitive and prescriptive SoMe policies; with these varying tremendously in comprehensiveness, but with a narrow focus on security and employers reputation; in contrast with national strategy. Recommendations are that policy revision is undertaken with consultation by more than one stakeholder, and SoMe training is offered for all members of NHS staff. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.

Bose Condensation at He-4 Interfaces

NASA Technical Reports Server (NTRS)

Draeger, E. W.; Ceperley, D. M.

2003-01-01

Path Integral Monte Carlo was used to calculate the Bose-Einstein condensate fraction at the surface of a helium film at T = 0:77 K, as a function of density. Moving from the center of the slab to the surface, the condensate fraction was found to initially increase with decreasing density to a maximum value of 0.9, before decreasing. Long wavelength density correlations were observed in the static structure factor at the surface of the slab. A surface dispersion relation was calculated from imaginary-time density-density correlations. Similar calculations of the superfluid density throughout He-4 droplets doped with linear impurities (HCN)(sub n) are presented. After deriving a local estimator for the superfluid density distribution, we find a decreased superfluid response in the first solvation layer. This effective normal fluid exhibits temperature dependence similar to that of a two-dimensional helium system.

Condensed nitrate, sulfate, and chloride in Antarctic stratospheric aerosols

NASA Technical Reports Server (NTRS)

Pueschel, R. F.; Snetsinger, K. G.; Toon, O. B.; Ferry, G. V.; Oberbeck, V. R.; Starr, W. L.; Chan, K. R.; Goodman, J. K.

1989-01-01

The 1987 Airborne Antarctic Ozone Experiment, in which the NO3, Cl, and SO4 contents of stratospheric aerosols were estimated, is discussed. The aerosol size and chemical composition measurements were carried out on samples collected during August 17 to September 4, 1987. The data indicate that condensed nitrate is found below a threshold temperature of 193.6 + or - 3.0 K, which is generally found at latitudes exceeding 64 deg S. A negative correlation exists between condensed nitrate and ozone correlation.

Sodium sulfate: Vaporization thermodynamics and role in corrosive flames

NASA Technical Reports Server (NTRS)

Kohl, F. J.

1975-01-01

Gaseous species over liquid Na2SO4 were identified by the technique of molecular beam mass spectrometry. The heat and entropy of vaporization of the Na2SO4 molecule were measured directly. Comparisons of the experimental entropy with values calculated using various molecular parameters were used to estimate the molecular structure and vibrational frequencies. The thermodynamic properties of gaseous and condensed phase Na2SO4, along with additional pertinent species, were used in a computer program to calculate equilibrium flame compositions and temperatures for representative turbine engine and burner rig flames. Compositions were calculated at various fuel-to-oxidant ratios with additions of sulfur to the fuel and the components of sea salt to the intake air. Temperatures for condensation of Na2SO4 were obtained as a function of sulfur and sea salt concentrations.

Modelling and experimental verification of a water alleviation system for the NASP. [National Aerospace Plane

NASA Technical Reports Server (NTRS)

Vanfossen, G. James

1992-01-01

One possible low speed propulsion system for the National Aerospace Plane is a liquid air cycle engine (LACE). The LACE system uses the heat sink in the liquid hydrogen propellant to liquefy air in a heat exchanger which is then pumped up to high pressure and used as the oxidizer in a hydrogen liquid air rocket. The inlet airstream must be dehumidified or moisture could freeze on the cryogenic heat exchangers and block them. The main objective of this research has been to develop a computer simulation of the cold tube/antifreeze-spray water alleviation system and to verify the model with experimental data. An experimental facility has been built and humid air tests were conducted on a generic heat exchanger to obtain condensing data for code development. The paper describes the experimental setup, outlines the method of calculation used in the code, and presents comparisons of the calculations and measurements. Cause of discrepancies between the model and data are explained.

Efficient Calculation of Exact Exchange Within the Quantum Espresso Software Package

NASA Astrophysics Data System (ADS)

Barnes, Taylor; Kurth, Thorsten; Carrier, Pierre; Wichmann, Nathan; Prendergast, David; Kent, Paul; Deslippe, Jack

Accurate simulation of condensed matter at the nanoscale requires careful treatment of the exchange interaction between electrons. In the context of plane-wave DFT, these interactions are typically represented through the use of approximate functionals. Greater accuracy can often be obtained through the use of functionals that incorporate some fraction of exact exchange; however, evaluation of the exact exchange potential is often prohibitively expensive. We present an improved algorithm for the parallel computation of exact exchange in Quantum Espresso, an open-source software package for plane-wave DFT simulation. Through the use of aggressive load balancing and on-the-fly transformation of internal data structures, our code exhibits speedups of approximately an order of magnitude for practical calculations. Additional optimizations are presented targeting the many-core Intel Xeon-Phi ``Knights Landing'' architecture, which largely powers NERSC's new Cori system. We demonstrate the successful application of the code to difficult problems, including simulation of water at a platinum interface and computation of the X-ray absorption spectra of transition metal oxides.

Applying Quantum Monte Carlo to the Electronic Structure Problem

NASA Astrophysics Data System (ADS)

Powell, Andrew D.; Dawes, Richard

2016-06-01

Two distinct types of Quantum Monte Carlo (QMC) calculations are applied to electronic structure problems such as calculating potential energy curves and producing benchmark values for reaction barriers. First, Variational and Diffusion Monte Carlo (VMC and DMC) methods using a trial wavefunction subject to the fixed node approximation were tested using the CASINO code.[1] Next, Full Configuration Interaction Quantum Monte Carlo (FCIQMC), along with its initiator extension (i-FCIQMC) were tested using the NECI code.[2] FCIQMC seeks the FCI energy for a specific basis set. At a reduced cost, the efficient i-FCIQMC method can be applied to systems in which the standard FCIQMC approach proves to be too costly. Since all of these methods are statistical approaches, uncertainties (error-bars) are introduced for each calculated energy. This study tests the performance of the methods relative to traditional quantum chemistry for some benchmark systems. References: [1] R. J. Needs et al., J. Phys.: Condensed Matter 22, 023201 (2010). [2] G. H. Booth et al., J. Chem. Phys. 131, 054106 (2009).

Characterization of condenser microphones under different environmental conditions for accurate speed of sound measurements with acoustic resonators.

PubMed

Guianvarc'h, Cécile; Gavioso, Roberto M; Benedetto, Giuliana; Pitre, Laurent; Bruneau, Michel

2009-07-01

Condenser microphones are more commonly used and have been extensively modeled and characterized in air at ambient temperature and static pressure. However, several applications of interest for metrology and physical acoustics require to use these transducers in significantly different environmental conditions. Particularly, the extremely accurate determination of the speed of sound in monoatomic gases, which is pursued for a determination of the Boltzmann constant k by an acoustic method, entails the use of condenser microphones mounted within a spherical cavity, over a wide range of static pressures, at the temperature of the triple point of water (273.16 K). To further increase the accuracy achievable in this application, the microphone frequency response and its acoustic input impedance need to be precisely determined over the same static pressure and temperature range. Few previous works examined the influence of static pressure, temperature, and gas composition on the microphone's sensitivity. In this work, the results of relative calibrations of 1/4 in. condenser microphones obtained using an electrostatic actuator technique are presented. The calibrations are performed in pure helium and argon gas at temperatures near 273 K and in the pressure range between 10 and 600 kPa. These experimental results are compared with the predictions of a realistic model available in the literature, finding a remarkable good agreement. The model provides an estimate of the acoustic impedance of 1/4 in. condenser microphones as a function of frequency and static pressure and is used to calculate the corresponding frequency perturbations induced on the normal modes of a spherical cavity when this is filled with helium or argon gas.

The Influence of a Lower Heated Tube on Nucleate Pool Boiling from a Horizontal Tube

DTIC Science & Technology

1992-06-01

9 C. CONDENSER SECTION .................................... 12 D. COOLING SECTION...lower tube kc thermal conductivity of copper L active boiling tube length Lu non-boiling tube length x Nu Nusselt number p tube outside wall perimeter Pr...teflon endplates. 2. A condenser , assembled using a similar Pyrex-glass tee with aluminum endplates. 3. A reservoir for R- 114 liquid storage. 4. A

Engine Oils with a New Composition of Additives

DTIC Science & Technology

A lubricant additive composition IKhP (2.6% BFK, a Ba salt of a CH2O- alkylphenol condensation product; 1.4% SB-3, a Ba sulfonate; 1.2% IN-KhP-21, a...Ba salt of a CH2O-NH3- alkylphenol condensation product; 0.005% PMS-200A; and 0. 5% AzNII) is discussed in relationship to its use as an automobile oil

The properties of syringyl, guaiacyl and p-hydroxyphenyl artificial lignins

PubMed Central

Bland, D. E.; Logan, A. F.

1965-01-01

1. Artificial lignins have been produced on potato parenchyma. 2. The methoxyl-free lignin and 4-hydroxy-3-methoxy (guaiacyl) lignins could be estimated by the sulphuric acid method but the 4-hydroxy-3,5-dimethoxy (syringyl) lignins could not. 3. Permanganate oxidation of isolated p-coumaric lignin gave 4-hydroxybenzoic acid, 4-hydroxyisophthalic acid and small amounts of hydroxytrimesic acid and 4-hydroxyphthalic acid. Ferulic lignin gave vanillic acid and 5-carboxyvanillic acid and also small amounts of 4-hydroxybenzoic acid and dehydrodivanillic acid. The sinapic lignin gave traces of syringic acid and of 4-hydroxybenzoic acid. 4. The p-coumaric lignin is a highly condensed polymer. The ferulic lignin is partly uncondensed and partly condensed through the 5-position like gymnosperm lignin. The sinapic lignin shows no evidence of condensation and is probably an ether-linked polymer. PMID:14340102

Finite Density Condensation and Scattering Data: A Study in ϕ4 Lattice Field Theory

NASA Astrophysics Data System (ADS)

Gattringer, Christof; Giuliani, Mario; Orasch, Oliver

2018-06-01

We study the quantum field theory of a charged ϕ4 field in lattice regularization at finite density and low temperature in 2 and 4 dimensions with the goal of analyzing the connection of condensation phenomena to scattering data in a nonperturbative way. The sign problem of the theory at nonzero chemical potential μ is overcome by using a worldline representation for the Monte Carlo simulation. At low temperature we study the particle number as a function of μ and observe the steps for 1-, 2-, and 3-particle condensation. We determine the corresponding critical values μncrit , n =1 , 2, 3 and analyze their dependence on the spatial extent L of the lattice. Linear combinations of the μncrit give the interaction energies in the 2- and 3-particle sectors and their dependence on L is related to scattering data by Lüscher's formula and its generalizations to three particles. For two dimensions we determine the scattering phase shift and for four dimensions the scattering length. We cross-check our results with a determination of the mass and the 2- and 3-particle energies from conventional 2-, 4-, and 6-point correlators at zero chemical potential. The letter demonstrates that the physics of condensation at finite density and low temperature is closely related to scattering data of a quantum field theory.

Reducing Errors in Satellite Simulated Views of Clouds with an Improved Parameterization of Unresolved Scales

NASA Astrophysics Data System (ADS)

Hillman, B. R.; Marchand, R.; Ackerman, T. P.

2016-12-01

Satellite instrument simulators have emerged as a means to reduce errors in model evaluation by producing simulated or psuedo-retrievals from model fields, which account for limitations in the satellite retrieval process. Because of the mismatch in resolved scales between satellite retrievals and large-scale models, model cloud fields must first be downscaled to scales consistent with satellite retrievals. This downscaling is analogous to that required for model radiative transfer calculations. The assumption is often made in both model radiative transfer codes and satellite simulators that the unresolved clouds follow maximum-random overlap with horizontally homogeneous cloud condensate amounts. We examine errors in simulated MISR and CloudSat retrievals that arise due to these assumptions by applying the MISR and CloudSat simulators to cloud resolving model (CRM) output generated by the Super-parameterized Community Atmosphere Model (SP-CAM). Errors are quantified by comparing simulated retrievals performed directly on the CRM fields with those simulated by first averaging the CRM fields to approximately 2-degree resolution, applying a "subcolumn generator" to regenerate psuedo-resolved cloud and precipitation condensate fields, and then applying the MISR and CloudSat simulators on the regenerated condensate fields. We show that errors due to both assumptions of maximum-random overlap and homogeneous condensate are significant (relative to uncertainties in the observations and other simulator limitations). The treatment of precipitation is particularly problematic for CloudSat-simulated radar reflectivity. We introduce an improved subcolumn generator for use with the simulators, and show that these errors can be greatly reduced by replacing the maximum-random overlap assumption with the more realistic generalized overlap and incorporating a simple parameterization of subgrid-scale cloud and precipitation condensate heterogeneity. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND NO. SAND2016-7485 A

MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Dhongik S.; Jo, HangJin; Fu, Wen

A multi-application small light water reactor (MASLWR) conceptual design was developed by Oregon State University (OSU) with emphasis on passive safety systems. The passive containment safety system employs condensation and natural circulation to achieve the necessary heat removal from the containment in case of postulated accidents. Containment condensation experiments at the MASLWR test facility at OSU are modeled and analyzed with MELCOR, a system-level reactor accident analysis computer code. The analysis assesses its ability to predict condensation heat transfer in the presence of noncondensable gas for accidents where high-energy steam is released into the containment. This work demonstrates MELCOR’s abilitymore » to predict the pressure-temperature response of the scaled containment. Our analysis indicates that the heat removal rates are underestimated in the experiment due to the limited locations of the thermocouples and applies corrections to these measurements by conducting integral energy analyses along with CFD simulation for confirmation. Furthermore, the corrected heat removal rate measurements and the MELCOR predictions on the heat removal rate from the containment show good agreement with the experimental data.« less

The annual pressure cycle on Mars: Results from the LMD Martian atmospheric general circulation model

NASA Technical Reports Server (NTRS)

Hourdin, Frederic; Forget, Francois; Talagrand, O.

1993-01-01

We have been developing a General Circulation Model (GCM) of the martian atmosphere since 1989. The model has been described rather extensively elsewhere and only the main characteristics are given here. The dynamical part of the model, adapted from the LMD terrestrial climate model, is based on a finite-difference formulation of the classical 'primitive equations of meteorology.' The radiative transfer code includes absorption and emission by CO2 (carefully validated by comparison to line-by-line calculations) and dust in the thermal range and absorption and scattering by dust in the visible range. Other physical parameterizations are included: modeling of vertical turbulent mixing, dry convective adjustment (in order to prevent vertical unstable temperature profiles), and a multilayer model of the thermal conduction in the soil. Finally, the condensation-sublimation of CO2 is introduced through specification of a pressure-dependent condensation temperature. The atmospheric and surface temperatures are prevented from falling below this critical temperature by condensation and direct precipitation onto the surface of atmospheric CO2. The only prespecified spatial fields are the surface thermal inertia, albedo, and topography.

MELCOR Analysis of OSU Multi-Application Small Light Water Reactor (MASLWR) Experiment

DOE PAGES

Yoon, Dhongik S.; Jo, HangJin; Fu, Wen; ...

2017-05-23

A multi-application small light water reactor (MASLWR) conceptual design was developed by Oregon State University (OSU) with emphasis on passive safety systems. The passive containment safety system employs condensation and natural circulation to achieve the necessary heat removal from the containment in case of postulated accidents. Containment condensation experiments at the MASLWR test facility at OSU are modeled and analyzed with MELCOR, a system-level reactor accident analysis computer code. The analysis assesses its ability to predict condensation heat transfer in the presence of noncondensable gas for accidents where high-energy steam is released into the containment. This work demonstrates MELCOR’s abilitymore » to predict the pressure-temperature response of the scaled containment. Our analysis indicates that the heat removal rates are underestimated in the experiment due to the limited locations of the thermocouples and applies corrections to these measurements by conducting integral energy analyses along with CFD simulation for confirmation. Furthermore, the corrected heat removal rate measurements and the MELCOR predictions on the heat removal rate from the containment show good agreement with the experimental data.« less

Detection of Dust Condensations in the Orion Bar Photon-dominated Region

NASA Astrophysics Data System (ADS)

Qiu, Keping; Xie, Zeqiang; Zhang, Qizhou

2018-03-01

We report Submillimeter Array dust continuum and molecular spectral line observations toward the Orion Bar photon-dominated region (PDR). The 1.2 mm continuum map reveals, for the first time, a total of nine compact (r < 0.01 pc) dust condensations located within a distance of ∼0.03 pc from the dissociation front of the PDR. Part of the dust condensations are also seen in spectral line emissions of CS (5–4) and H2CS (71,7–61,6), though the CS map also reveals dense gas further away from the dissociation front. We also detect compact emissions in H2CS (60,6–50,5), (62,4–52,3) and C34S, C33S (4–3) toward bright dust condensations. The line ratio of H2CS (60,6–50,5)/(62,4–52,3) suggests a temperature of 73 ± 58 K. A nonthermal velocity dispersion of ∼0.25–0.50 km s‑1 is derived from the high spectral resolution C34S data and indicates a subsonic to transonic turbulence in the condensations. The masses of the condensations are estimated from the dust emission, and range from 0.03 to 0.3 M ⊙, all significantly lower than any critical mass that is required for self-gravity to play a crucial role. Thus the condensations are not gravitationally bound, and could not collapse to form stars. In cooperating with recent high-resolution observations of the compressed surface layers of the molecular cloud in the Bar, we speculate that the condensations are produced as a high-pressure wave induced by the expansion of the H II region compresses and enters the cloud. A velocity gradient along a direction perpendicular to the major axis of the Bar is seen in H2CS (71,7–61,6), and is consistent with the scenario that the molecular gas behind the dissociation front is being compressed.

Estimation of homogeneous nucleation flux via a kinetic model

NASA Technical Reports Server (NTRS)

Wilcox, C. F.; Bauer, S. H.

1991-01-01

The proposed kinetic model for condensation under homogeneous conditions, and the onset of unidirectional cluster growth in supersaturated gases, does not suffer from the conceptual flaws that characterize classical nucleation theory. When a full set of simultaneous rate equation is solved, a characteristic time emerges, for each cluster size, at which the production rate, and its rate of conversion to the next size (n + 1) are equal. Procedures for estimating the essential parameters are proposed; condensation fluxes J(kin) exp ss are evaluated. Since there are practical limits to the cluster size that can be incorporated in the set of simultaneous first-order differential equations, a code was developed for computing an approximate J(th) exp ss based on estimates of a 'constrained equilibrium' distribution, and identification of its minimum.

Determination of polar organic solutes in oil-shale retort water

USGS Publications Warehouse

Leenheer, J.A.; Noyes, T.I.; Stuber, H.A.

1982-01-01

A variety of analytical methods were used to quantitatively determine polar organic solutes in process retort water and a gas-condensate retort water produced in a modified in situ oil-shale retort. Specific compounds accounting for 50% of the dissolved organic carbon were identified in both retort waters. In the process water, 42% of the dissolved organic carbon consisted of a homologous series of fatty acids from C2 to C10. Dissolved organic carbon percentages for other identified compound classes were as follows: aliphatic dicarboxylic acids, 1.4%; phenols, 2.2%; hydroxypyridines, 1.1%; aliphatic amides, 1.2%. In the gas-condensate retort water, aromatic amines were most abundant at 19.3% of the dissolved organic carbon, followed by phenols (17.8%), nitriles (4.3%), aliphatic alcohols (3.5%), aliphatic ketones (2.4%), and lactones (1.3%). Steam-volatile organic solutes were enriched in the gas-condensate retort water, whereas nonvolatile acids and polyfunctional neutral compounds were predominant organic constituents of the process retort water.

Transformation of Litchi Pericarp-Derived Condensed Tannin with Aspergillus awamori

PubMed Central

Lin, Sen; Li, Qing; Yang, Bao; Duan, Xuewu; Zhang, Mingwei; Shi, John; Jiang, Yueming

2016-01-01

Condensed tannin is a ubiquitous polyphenol in plants that possesses substantial antioxidant capacity. In this study, we have investigated the polyphenol extraction recovery and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of the extracted polyphenol after litchi pericarp is treated with Aspergillus awamori, Aspergillus sojae or Aspergillus oryzae. We have further explored the activity of A. awamori in the formation of condensed tannin. The treatment of A. awamori appeared to produce the highest antioxidant activity of polyphenol from litchi pericarp. Further studies suggested that the treatment of A. awamori releases the non-extractable condensed tannin from cell walls of litchi pericarp. The total extractable tannin in the litchi pericarp residue after a six-time extraction with 60% ethanol increased from 199.92 ± 14.47–318.38 ± 7.59 μg/g dry weight (DW) after the treatment of A. awamori. The ESI-TOF-MS and HPLC-MS2 analyses further revealed that treatment of A. awamori degraded B-type condensed tannin (condensed flavan-3-ol via C4–C8 linkage), but exhibited a limited capacity to degrade the condensed tannin containing A-type linkage subunits (C4–C8 coupled C2–O–C7 linkage). These results suggest that the treatment of A. awamori can significantly improve the production of condensed tannin from litchi pericarp. PMID:27420043

The seven sins in academic behavior in the natural sciences.

PubMed

van Gunsteren, Wilfred F

2013-01-02

"Seven deadly sins" in modern academic research and publishing can be condensed into a list ranging from poorly described experimental or computational setups to falsification of data. This Essay describes these sins and their ramifications, and serves as a code of best practice for researchers in their quest for scientific truth. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 63.8005 - What requirements apply to my process vessels?

Code of Federal Regulations, 2011 CFR

2011-07-01

... condensers, as defined in § 63.1251, are not considered to be control devices for process vessels. (d... vessels. (2) For the initial compliance demonstration for condensers, you must determine uncontrolled... process condenser is properly operated according to the procedures specified in § 63.1257(d)(2)(i)(C)(4...

Quark-hadron phase structure of QCD matter from SU(4) Polyakov linear sigma model

NASA Astrophysics Data System (ADS)

Diab, Abdel Magied Abdel Aal; Tawfik, Abdel Nasser

2018-04-01

The SU(4) Polyakov linear sigma model (PLSM) is extended towards characterizing the chiral condensates, σl, σs and σc of light, strange and charm quarks, respectively and the deconfinement order-parameters φ and φ at finite temperatures and densities (chemical potentials). The PLSM is considered to study the QCD equation of state in the presence of the chiral condensate of charm for different finite chemical potentials. The PLSM results are in a good agreement with the recent lattice QCD simulations. We conclude that, the charm condensate is likely not affected by the QCD phase-transition, where the corresponding critical temperature is greater than that of the light and strange quark condensates.

Prebiotic condensation reactions using cyanamide

NASA Technical Reports Server (NTRS)

Sherwood, E.; Nooner, D. W.; Eichberg, J.; Epps, D. E.; Oro, J.

1978-01-01

Condensation reactions in cyanamide, 4-amino-5-imidazole-carboxamide and cyanamide, imidazole systems under dehydrating conditions at moderate temperatures (60 to 100 deg C) were investigated. The cyanamide, imidazole system was used for synthesis of palmitoylglycerols from ammonium palmitate and glycerol. With the addition of deoxythymidine to the former system, P1, P2-dideoxythymidine 5 prime-phosphate was obtained; the same cyanamide, 4-amino-5-imidazole-carboxamide system was used to synthesize deoxythymidine oligonucleotides using deoxythymidine 5 prime-phosphate and deoxythymidine 5 prime-triphosphate, and peptides using glycine, phenylalanine or isoleucine with adenosine 5 prime-triphosphate. The pH requirements for these reactions make their prebiotic significance questionable; however, it is conceivable that they could occur in stable pockets of low interlayer acidity in a clay such as montmorillonite.

The Atmospheric Response to High Nonthermal Electron Beam Fluxes in Solar Flares. I. Modeling the Brightest NUV Footpoints in the X1 Solar Flare of 2014 March 29

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kowalski, Adam F.; Allred, Joel C.; Daw, Adrian

2017-02-10

The 2014 March 29 X1 solar flare (SOL20140329T17:48) produced bright continuum emission in the far- and near-ultraviolet (NUV) and highly asymmetric chromospheric emission lines, providing long-sought constraints on the heating mechanisms of the lower atmosphere in solar flares. We analyze the continuum and emission line data from the Interface Region Imaging Spectrograph (IRIS) of the brightest flaring magnetic footpoints in this flare. We compare the NUV spectra of the brightest pixels to new radiative-hydrodynamic predictions calculated with the RADYN code using constraints on a nonthermal electron beam inferred from the collisional thick-target modeling of hard X-ray data from Reuven Ramatymore » High Energy Solar Spectroscopic Imager . We show that the atmospheric response to a high beam flux density satisfactorily achieves the observed continuum brightness in the NUV. The NUV continuum emission in this flare is consistent with hydrogen (Balmer) recombination radiation that originates from low optical depth in a dense chromospheric condensation and from the stationary beam-heated layers just below the condensation. A model producing two flaring regions (a condensation and stationary layers) in the lower atmosphere is also consistent with the asymmetric Fe ii chromospheric emission line profiles observed in the impulsive phase.« less

The Atmospheric Response to High Nonthermal Electron Beam Fluxes in Solar Flares. I. Modeling the Brightest NUV Footpoints in the X1 Solar Flare of 2014 March 29

NASA Technical Reports Server (NTRS)

Kowalski, Adam F.; Allred, Joel C.; Daw, Adrian N.; Cauzzi, Gianna; Carlsson, Mats

2017-01-01

The 2014 March 29 X1 solar flare (SOL20140329T17:48) produced bright continuum emission in the far- and near-ultraviolet (NUV) and highly asymmetric chromospheric emission lines, providing long-sought constraints on the heating mechanisms of the lower atmosphere in solar flares. We analyze the continuum and emission line data from the Interface Region Imaging Spectrograph (IRIS) of the brightest flaring magnetic footpoints in this flare. We compare the NUV spectra of the brightest pixels to new radiative-hydrodynamic predictions calculated with the RADYN code using constraints on a nonthermal electron beam inferred from the collisional thick-target modeling of hard X-ray data from Reuven Ramaty High Energy Solar Spectroscopic Imager. We show that the atmospheric response to a high beam flux density satisfactorily achieves the observed continuum brightness in the NUV. The NUV continuum emission in this flare is consistent with hydrogen (Balmer) recombination radiation that originates from low optical depth in a dense chromospheric condensation and from the stationary beam-heated layers just below the condensation. A model producing two flaring regions (a condensation and stationary layers) in the lower atmosphere is also consistent with the asymmetric Fe II chromospheric emission line profiles observed in the impulsive phase.

The SAS4A/SASSYS-1 Safety Analysis Code System, Version 5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fanning, T. H.; Brunett, A. J.; Sumner, T.

The SAS4A/SASSYS-1 computer code is developed by Argonne National Laboratory for thermal, hydraulic, and neutronic analysis of power and flow transients in liquidmetal- cooled nuclear reactors (LMRs). SAS4A was developed to analyze severe core disruption accidents with coolant boiling and fuel melting and relocation, initiated by a very low probability coincidence of an accident precursor and failure of one or more safety systems. SASSYS-1, originally developed to address loss-of-decay-heat-removal accidents, has evolved into a tool for margin assessment in design basis accident (DBA) analysis and for consequence assessment in beyond-design-basis accident (BDBA) analysis. SAS4A contains detailed, mechanistic models of transientmore » thermal, hydraulic, neutronic, and mechanical phenomena to describe the response of the reactor core, its coolant, fuel elements, and structural members to accident conditions. The core channel models in SAS4A provide the capability to analyze the initial phase of core disruptive accidents, through coolant heat-up and boiling, fuel element failure, and fuel melting and relocation. Originally developed to analyze oxide fuel clad with stainless steel, the models in SAS4A have been extended and specialized to metallic fuel with advanced alloy cladding. SASSYS-1 provides the capability to perform a detailed thermal/hydraulic simulation of the primary and secondary sodium coolant circuits and the balance-ofplant steam/water circuit. These sodium and steam circuit models include component models for heat exchangers, pumps, valves, turbines, and condensers, and thermal/hydraulic models of pipes and plena. SASSYS-1 also contains a plant protection and control system modeling capability, which provides digital representations of reactor, pump, and valve controllers and their response to input signal changes.« less

Density-induced suppression of the {alpha}-particle condensate in nuclear matter and the structure of {alpha}-cluster states in nuclei

DOE Office of Scientific and Technical Information (OSTI.GOV)

Funaki, Y.; Horiuchi, H.; International Institute for Advanced Studies, Kizugawa 619-0225

2008-06-15

At low densities, with decreasing temperatures, in symmetric nuclear matter {alpha} particles are formed, which eventually give raise to a quantum condensate with four-nucleon {alpha}-like correlations (quartetting). Starting with a model of {alpha} matter, where undistorted {alpha} particles interact via an effective interaction such as the Ali-Bodmer potential, the suppression of the condensate fraction at zero temperature with increasing density is considered. Using a Jastrow-Feenberg approach, it is found that the condensate fraction vanishes near saturation density. Additionally, the modification of the internal state of the {alpha} particle due to medium effects will further reduce the condensate. In finite systems,more » an enhancement of the S-state wave function of the center-of-mass orbital of {alpha}-particle motion is considered as the correspondence to the condensate. Wave functions have been constructed for self-conjugate 4n nuclei that describe the condensate state but are fully antisymmetrized on the nucleonic level. These condensate-like cluster wave functions have been successfully applied to describe properties of low-density states near the n{alpha} threshold. Comparison with orthogonality condition model calculations in {sup 12}C and {sup 16}O shows strong enhancement of the occupation of the S-state center-of-mass orbital of the {alpha} particles. This enhancement is decreasing if the baryon density increases, similar to the density-induced suppression of the condensate fraction in {alpha} matter. The ground states of {sup 12}C and {sup 16}O show no enhancement at all, thus a quartetting condensate cannot be formed at saturation densities.« less

Heat transfer during condensation of steam from steam-gas mixtures in the passive safety systems of nuclear power plants

NASA Astrophysics Data System (ADS)

Portnova, N. M.; Smirnov, Yu B.

2017-11-01

A theoretical model for calculation of heat transfer during condensation of multicomponent vapor-gas mixtures on vertical surfaces, based on film theory and heat and mass transfer analogy is proposed. Calculations were performed for the conditions implemented in experimental studies of heat transfer during condensation of steam-gas mixtures in the passive safety systems of PWR-type reactors of different designs. Calculated values of heat transfer coefficients for condensation of steam-air, steam-air-helium and steam-air-hydrogen mixtures at pressures of 0.2 to 0.6 MPa and of steam-nitrogen mixture at the pressures of 0.4 to 2.6 MPa were obtained. The composition of mixtures and vapor-to-surface temperature difference were varied within wide limits. Tube length ranged from 0.65 to 9.79m. The condensation of all steam-gas mixtures took place in a laminar-wave flow mode of condensate film and turbulent free convection in the diffusion boundary layer. The heat transfer coefficients obtained by calculation using the proposed model are in good agreement with the considered experimental data for both the binary and ternary mixtures.

Peroxyoxalate chemiluminescence detection of condensates of malondialdehyde with thiobarbituric acids using a flow system.

PubMed

Nakashima, K; Nagata, M; Takahashi, M; Akiyama, S

1992-01-01

The peroxyoxalate chemiluminescence(CL) detection method for the evaluation of the CL intensity of malondialdehyde(MDA) condensates with seven 2-thiobarbituric acid derivatives is described. The method consists of a flow injection technique together with a CL detection system using bis(2,4,6-trichlorophenyl) oxalate(TCPO) and hydrogen peroxide as chemiluminogenic reagents. Linear correlations between CL intensity and concentration are obtained for pmol levels of condensates. Among the condensates, 1,3-diethyl-2-thiobarbituric acid(DETBA)-MDA shows the largest CL intensity. High performance liquid chromatography (HPLC)/CL detection of DETBA-MDA and 1,3-diphenyl-2-thiobarbituric acid(DPTBA)-MDA using a mixture of TCPO and hydrogen peroxide in acetonitrile as a postcolumn reagent solution is also described. The detection limits for DETBA-MDA and DPTBA-MDA are 20 and 200 fmol, respectively, per 20 microL injection at a signal-to-noise ratio of 2. This HPLC/CL detection system was applied to the determination of MDA in rat brains by using DETBA as a fluorescent derivatizing reagent.

Decoding a Decision Process in the Neuronal Population of Dorsal Premotor Cortex.

PubMed

Rossi-Pool, Román; Zainos, Antonio; Alvarez, Manuel; Zizumbo, Jerónimo; Vergara, José; Romo, Ranulfo

2017-12-20

When trained monkeys discriminate the temporal structure of two sequential vibrotactile stimuli, dorsal premotor cortex (DPC) showed high heterogeneity among its neuronal responses. Notably, DPC neurons coded stimulus patterns as broader categories and signaled them during working memory, comparison, and postponed decision periods. Here, we show that such population activity can be condensed into two major coding components: one that persistently represented in working memory both the first stimulus identity and the postponed informed choice and another that transiently coded the initial sensory information and the result of the comparison between the two stimuli. Additionally, we identified relevant signals that coded the timing of task events. These temporal and task-parameter readouts were shown to be strongly linked to the monkeys' behavior when contrasted to those obtained in a non-demanding cognitive control task and during error trials. These signals, hidden in the heterogeneity, were prominently represented by the DPC population response. Copyright © 2017 Elsevier Inc. All rights reserved.

PREFACE: Proceedings of the First International Workshop on the Theoretical Calculation of ELNES and XANES (TEX2008) (Nagoya, Japan, 2-4 July 2008) Proceedings of the First International Workshop on the Theoretical Calculation of ELNES and XANES (TEX2008) (Nagoya, Japan, 2-4 July 2008)

NASA Astrophysics Data System (ADS)

Tanaka, Isao; Mizoguchi, Teruyasu; Yamamoto, Tomoyuki

2009-03-01

Both electron energy loss near edge structure (ELNES) spectroscopy and x-ray absorption near edge structure (XANES) spectroscopy provide information on the local structural and chemical environments of selected elements of interest. Recent technological progress in scanning transmission electron microscopy has enabled ELNES measurements with atomic column spatial resolution. Very dilute concentrations (nanograms per milliliter or ppb level) of dopants can be observed using third-generation synchrotron facilities when x-ray fluorescence is measured with highly efficient detectors. With such technical developments, ELNES and XANES have become established as essential tools in a large number of fields of natural science, including condensed matter physics, chemistry, mineralogy and materials science. In addition to these developments in experimental methodology, notable progress in reproducing spectra using theoretical methods has recently been made. Using first-principles methods, one can analyze and interpret spectra without reference to experiment. This is quite important since we are often interested in the analysis of exotic materials or specific atoms located at lattice discontinuities such as surfaces and interfaces, where appropriate experimental data are difficult to obtain. Using the structures predicted by reliable first-principles calculations, one can calculate theoretical ELNES and XANES spectra without too much difficulty even in such cases. Despite the fact that ELNES and XANES probe the same phenomenon—essentially the electric dipole transition from a core orbital to an unoccupied band—there have not been many opportunities for researchers in the two areas to meet and discuss. Theoretical calculations of ELNES spectra have been mainly confined to the electron microscopy community. On the other hand, the theory of XANES has been developed principally by researchers in the x-ray community. Publications describing the methods have been written more-or-less independently by the two communities. The three-day workshop on the Theoretical Calculation of ELNES and XANES (TEX2008) was planned to help remedy this situation. It aimed to demonstrate capability of state-of-the-art theoretical techniques to explain and predict ELNES and XANES spectra, and to allow deep discussion between scientists in the two communities. It also provided an excellent opportunity to introduce experimentalists to the computational techniques available. Invited talks and poster presentations by leading scientists were given on the first day, which was followed by tutorial sessions for five computer programs on the second and third days. Excellent lectures were given by Peter Blaha (Vienna, Austria) on the WIEN2k code, Chris J Pickard (St Andrews, UK) on the CASTEP code, John J Rehr (Seattle, USA) on the FEFF8 code, Frank de Groot (Utrecht, The Netherlands) on the CTM4XAS code, and Hidekazu Ikeno (Kyoto, Japan) on the first-principles CI-multiplet code. Thanks to the enthusiastic participation of more than 100 scientists from around the world, the workshop was a complete success. The aim of this special issue in Journal of Physics: Condensed Matter is to share with the readers the most up-to-date knowledge presented at the workshop. We believe this will prove useful as a reference for researchers in many different fields, as well as an overview of the current status and future directions of theoretical calculations for ELNES and XANES. TEX2008 was a satellite meeting of the First International Symposium on Advanced Microscopy and Theoretical Calculations (AMTC1) (Nagoya, Japan, 29-30 June 2008), which was held in commemoration of the establishment of the Nanostuctures Research Laboratory (NSRL) at the Japan Fine Ceramics Center (JFCC) and as a daughter event of EXPO 2005, Aichi, Japan. A Grant-in-Aid for Scientific Research on Priority Areas 'Nano Materials Science for Atomic-Scale Modification' from the Ministry of Education, Culture, Sports and Technology (MEXT) and support from the Chubu Economic Federation for the workshop are gratefully acknowledged.

Diffusion Flame Stabilization

NASA Technical Reports Server (NTRS)

Takahashi, Fumiaki; Katta, V. R.

2006-01-01

Diffusion flames are commonly used for industrial burners in furnaces and flares. Oxygen/fuel burners are usually diffusion burners, primarily for safety reasons, to prevent flashback and explosion in a potentially dangerous system. Furthermore, in most fires, condensed materials pyrolyze, vaporize, and burn in air as diffusion flames. As a result of the interaction of a diffusion flame with burner or condensed-fuel surfaces, a quenched space is formed, thus leaving a diffusion flame edge, which plays an important role in flame holding in combustion systems and fire spread through condensed fuels. Despite a long history of jet diffusion flame studies, lifting/blowoff mechanisms have not yet been fully understood, compared to those of premixed flames. In this study, the structure and stability of diffusion flames of gaseous hydrocarbon fuels in coflowing air at normal earth gravity have been investigated experimentally and computationally. Measurements of the critical mean jet velocity (U(sub jc)) of methane, ethane, or propane at lifting or blowoff were made as a function of the coflowing air velocity (U(sub a)) using a tube burner (i.d.: 2.87 mm). By using a computational fluid dynamics code with 33 species and 112 elementary reaction steps, the internal chemical-kinetic structures of the stabilizing region of methane and propane flames were investigated. A peak reactivity spot, i.e., reaction kernel, is formed in the flame stabilizing region due to back-diffusion of heat and radical species against an oxygen-rich incoming flow, thus holding the trailing diffusion flame. The simulated flame base moved downstream under flow conditions close to the measured stability limit.

Diffusion Flame Stabilization

NASA Technical Reports Server (NTRS)

Takahashi, Fumiaki; Katta, Viswanath R.

2007-01-01

Diffusion flames are commonly used for industrial burners in furnaces and flares. Oxygen/fuel burners are usually diffusion burners, primarily for safety reasons, to prevent flashback and explosion in a potentially dangerous system. Furthermore, in most fires, condensed materials pyrolyze, vaporize, and burn in air as diffusion flames. As a result of the interaction of a diffusion flame with burner or condensed-fuel surfaces, a quenched space is formed, thus leaving a diffusion flame edge, which plays an important role in flame holding in combustion systems and fire spread through condensed fuels. Despite a long history of jet diffusion flame studies, lifting/blowoff mechanisms have not yet been fully understood, compared to those of premixed flames. In this study, the structure and stability of diffusion flames of gaseous hydrocarbon fuels in coflowing air at normal earth gravity have been investigated experimentally and computationally. Measurements of the critical mean jet velocity (U(sub jc)) of methane, ethane, or propane at lifting or blowoff were made as a function of the coflowing air velocity (U(sub a)) using a tube burner (i.d.: 2.87 mm) (Fig. 1, left). By using a computational fluid dynamics code with 33 species and 112 elementary reaction steps, the internal chemical-kinetic structures of the stabilizing region of methane and propane flames were investigated (Fig. 1, right). A peak reactivity spot, i.e., reaction kernel, is formed in the flame stabilizing region due to back-diffusion of heat and radical species against an oxygen-rich incoming flow, thus holding the trailing diffusion flame. The simulated flame base moved downstream under flow conditions close to the measured stability limit.

Thermal Condensation of Glycine and Alanine on Metal Ferrite Surface: Primitive Peptide Bond Formation Scenario

PubMed Central

Iqubal, Md. Asif; Sharma, Rachana; Jheeta, Sohan; Kamaluddin

2017-01-01

The amino acid condensation reaction on a heterogeneous mineral surface has been regarded as one of the important pathways for peptide bond formation. Keeping this in view, we have studied the oligomerization of the simple amino acids, glycine and alanine, on nickel ferrite (NiFe2O4), cobalt ferrite (CoFe2O4), copper ferrite (CuFe2O4), zinc ferrite (ZnFe2O4), and manganese ferrite (MnFe2O4) nanoparticles surfaces, in the temperature range from 50–120 °C for 1–35 days, without applying any wetting/drying cycles. Among the metal ferrites tested for their catalytic activity, NiFe2O4 produced the highest yield of products by oligomerizing glycine to the trimer level and alanine to the dimer level, whereas MnFe2O4 was the least efficient catalyst, producing the lowest yield of products, as well as shorter oligomers of amino acids under the same set of experimental conditions. It produced primarily diketopiperazine (Ala) with a trace amount of alanine dimer from alanine condensation, while glycine was oligomerized to the dimer level. The trend in product formation is in accordance with the surface area of the minerals used. A temperature as low as 50 °C can even favor peptide bond formation in the present study, which is important in the sense that the condensation process is highly feasible without any sort of localized heat that may originate from volcanoes or hydrothermal vents. However, at a high temperature of 120 °C, anhydrides of glycine and alanine formation are favored, while the optimum temperature for the highest yield of product formation was found to be 90 °C. PMID:28346388

Laboratory measurement of the millimeter wave properties of liquid sulfuric acid (H2SO4). [study of microwave emission from Venus

NASA Technical Reports Server (NTRS)

Fahd, Antoine K.; Steffes, Paul G.

1991-01-01

The methodology and the results of laboratory measurements of the millimeter wave properties of liquid sulfuric acid are presented. Measurements conducted at 30-40 and 90-100 GHz are reported, using different concentrations of liquid H2SO4. The measured data are used to compute the expected opacity of H2SO4 condensates and their effects on the millimeter wave emission from Venus. The cloud condensate is found to have an effect on the emission from Venus. The calculated decrease in brightness temperature is well below the observed decrease in brightness temperature found by de Pater et al. (1991). It is suggested that other constituents such as gaseous H2SO4 also affect the observed variation in the brightness temperature.

An investigation of the microstructure and mechanical properties of electrochemically coated Ag(4)Sn dental alloy particles condensed in vitro

NASA Astrophysics Data System (ADS)

Marquez, Jose Antonio

As part of the ongoing scientific effort to develop a new amalgam-like material without mercury, a team of metallurgists and electrochemists at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, announced in 1993 the development of a new Ag-Sn dental alloy system without mercury that sought to replace conventional dental amalgams. They used spherical Ag3Sn and Ag4Sn intermetallic dental alloy particles, commonly used in conventional dental alloys, and coated them with electrodeposited silver with newly-developed electrolytic and immersion techniques. The particles had relatively pure silver coatings that were closely adherent to the intermetalfic cores. These silver-coated particles, due to silver's plasticity at room temperature, were condensed into PlexiglasRTM molds with the aid of an acidic surface activating solution (HBF4) and a mechanical condensing device, producing a metal-matrix composite with Ag3,4Sn filler particles surrounded by a cold-welded silver matrix. Since silver strain hardens rather easily, the layers had to be condensed in less than 0.5 mm increments to obtain a dense structure. Mechanical testing at NIST produced compressive strength values equal to or greater than those of conventional dental amalgams. Because of its potential for eliminating mercury as a constituent in dental amalgam, this material created a stir in dental circles when first developed and conceivably could prove to be a major breakthrough in the field of dental restoratives. To date, the chief impediments to its approval for human clinical applications by the Food and Drug Administration are the potentially-toxic surface activating solution used for oxide reduction, and the high condensation pressures needed for cold welding because of the tendency for silver to strain harden. In this related study, the author, who has practiced general dentistry for 25 years, evaluates some of the mechanical and microstructural properties of these electrochemically coated particles when they are amalgamated with mercury. Because of patent restrictions for the coated particles that protect the cold-welding work being done at NIST, these particles necessarily had to include mercury as a constituent for this investigation. (Abstract shortened by UMI.)

Modelling of Technological Solutions to 4th Generation DH Systems

NASA Astrophysics Data System (ADS)

Vigants, Edgars; Prodanuks, Toms; Vigants, Girts; Veidenbergs, Ivars; Blumberga, Dagnija

2017-11-01

Flue gas evaporation and condensing processes are investigated in a direct contact heat exchanger - condensing unit, which is installed after a furnace. By using equations describing processes of heat and mass transfer, as well as correlation coherences for determining wet gas parameters, a model is formed to create a no-filling, direct contact heat exchanger. Results of heating equipment modelling and experimental research on the gas condensing unit show, that the capacity of the heat exchanger increases, when return temperature of the district heating network decreases. In order to explain these alterations in capacity, the character of the changes in water vapour partial pressure, in the propelling force of mass transfer, in gas and water temperatures and in the determining parameters of heat transfer are used in this article. The positive impact on the direct contact heat exchanger by the decreased district heating (DH) network return temperature shows that introduction of the 4th generation DH system increases the energy efficiency of the heat exchanger. In order to make an assessment, the methodology suggested in the paper can be used in each particular situation.

Tri- and pentacalix[4]pyrroles: synthesis, characterization and their use in the extraction of halide salts.

PubMed

Aydogan, Abdullah; Akar, Ahmet

2012-02-13

Calixpyrrole-based oligomeric compounds were synthesized by "click chemistry" from the corresponding alkyne- and azide-functionalized calix[4]pyrroles. Calix[4]pyrrole 3, possessing an alkyne functional group, was prepared through a mixed condensation of pyrrole with acetone and but-3-ynyl 4-oxopentanoate. Another alkyne-group-containing calix[4]pyrrole 5 was obtained by treatment of 4'-hydroxyphenyl-functionalized calixpyrrole 4 with propargyl bromide. Tetrakis(azidopentyl)-functionalized calix[4]pyrrole 7 was synthesized by reacting NaN(3) with tetrabromopentyltetraethylcalix[4]pyrrole 6, which was prepared through a condensation reaction of pyrrole and 7-bromohept-2-one. Oligomeric calixpyrrole compounds were found to be capable of extracting tetrabutylammonium chloride and fluoride salts from aqueous media. Extraction abilities of the oligomeric compounds were monitored by NMR and UV/Vis spectroscopy and thermogravimetric analysis. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aerosol Constraints on the Atmosphere of the Hot Saturn-mass Planet WASP-49b

NASA Astrophysics Data System (ADS)

Cubillos, Patricio E.; Fossati, Luca; Erkaev, Nikolai V.; Malik, Matej; Tokano, Tetsuya; Lendl, Monika; Johnstone, Colin P.; Lammer, Helmut; Wyttenbach, Aurélien

2017-11-01

The strong, nearly wavelength-independent absorption cross section of aerosols produces featureless exoplanet transmission spectra, limiting our ability to characterize their atmospheres. Here, we show that even in the presence of featureless spectra, we can still characterize certain atmospheric properties. Specifically, we constrain the upper and lower pressure boundaries of aerosol layers, and present plausible composition candidates. We study the case of the bloated Saturn-mass planet WASP-49 b, where near-infrared observations reveal a flat transmission spectrum between 0.7 and 1.0 μm. First, we use a hydrodynamic upper-atmosphere code to estimate the pressure reached by the ionizing stellar high-energy photons at {10}-8 bar, setting the upper pressure boundary where aerosols could exist. Then, we combine HELIOS and Pyrat Bay radiative-transfer models to constrain the temperature and photospheric pressure of atmospheric aerosols, in a Bayesian framework. For WASP-49 b, we constrain the transmission photosphere (hence, the aerosol deck boundaries) to pressures above {10}-5 bar (100× solar metallicity), {10}-4 bar (solar), and {10}-3 bar (0.1× solar) as the lower boundary, and below {10}-7 bar as the upper boundary. Lastly, we compare condensation curves of aerosol compounds with the planet’s pressure-temperature profile to identify plausible condensates responsible for the absorption. Under these circumstances, we find these candidates: {{Na}}2{{S}} (at 100× solar metallicity); Cr and MnS (at solar and 0.1× solar) and forsterite, enstatite, and alabandite (at 0.1× solar).

Thermal Ablation Modeling for Silicate Materials

NASA Technical Reports Server (NTRS)

Chen, Yih-Kanq

2016-01-01

A general thermal ablation model for silicates is proposed. The model includes the mass losses through the balance between evaporation and condensation, and through the moving molten layer driven by surface shear force and pressure gradient. This model can be applied in the ablation simulation of the meteoroid and the glassy ablator for spacecraft Thermal Protection Systems. Time-dependent axisymmetric computations are performed by coupling the fluid dynamics code, Data-Parallel Line Relaxation program, with the material response code, Two-dimensional Implicit Thermal Ablation simulation program, to predict the mass lost rates and shape change. The predicted mass loss rates will be compared with available data for model validation, and parametric studies will also be performed for meteoroid earth entry conditions.

Design analysis of a Helium re-condenser

NASA Astrophysics Data System (ADS)

Muley, P. K.; Bapat, S. L.; Atrey, M. D.

2017-02-01

Modern helium cryostats deploy a cryocooler with a re-condenser at its II stage for in-situ re-condensation of boil-off vapor. The present work is a vital step in the ongoing research work of design of cryocooler based 100 litre helium cryostat with in-situ re-condensation. The cryostat incorporates a two stage Gifford McMahon cryocooler having specified refrigerating capacity of 40 W at 43 K for I stage and 1 W at 4.2 K for II stage. Although design of cryostat ensures thermal load for cryocooler below its specified refrigerating capacity at the second stage, successful in-situ re-condensation depends on proper design of re-condenser which forms the objective of this work. The present work proposes design of helium re-condenser with straight rectangular fins. Fins are analyzed for optimization of thermal performance parameters such as condensation heat transfer coefficient, surface area for heat transfer, re-condensing capacity, efficiency and effectiveness. The present work provides design of re-condenser with 19 integral fins each of 10 mm height and 1.5 mm thickness with a gap of 1.5 mm between two fins, keeping in mind the manufacturing feasibility, having efficiency of 80.96 % and effectiveness of 10.34.

Software Tools for Stochastic Simulations of Turbulence

DTIC Science & Technology

2015-08-28

client interface to FTI. Specefic client programs using this interface include the weather forecasting code WRF ; the high energy physics code, FLASH...client programs using this interface include the weather forecasting code WRF ; the high energy physics code, FLASH; and two locally constructed fluid...45 4.4.2.2 FLASH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 4.4.2.3 WRF

Thermal gain of CHP steam generator plants and heat supply systems

NASA Astrophysics Data System (ADS)

Ziganshina, S. K.; Kudinov, A. A.

2016-08-01

Heating calculation of the surface condensate heat recovery unit (HRU) installed behind the BKZ-420-140 NGM boiler resulting in determination of HRU heat output according to fire gas value parameters at the heat recovery unit inlet and its outlet, heated water quantity, combustion efficiency per boiler as a result of installation of HRU, and steam condensate discharge from combustion products at its cooling below condensing point and HRU heat exchange area has been performed. Inspection results of Samara CHP BKZ-420-140 NGM power boilers and field tests of the surface condensate heat recovery unit (HRU) made on the bimetal calorifier base KCk-4-11 (KSk-4-11) installed behind station no. 2 Ulyanovsk CHP-3 DE-10-14 GM boiler were the basis of calculation. Integration of the surface condensation heat recovery unit behind a steam boiler rendered it possible to increase combustion efficiency and simultaneously decrease nitrogen oxide content in exit gases. Influence of the blowing air moisture content, the excess-air coefficient in exit gases, and exit gases temperature at the HRU outlet on steam condensate amount discharge from combustion products at its cooling below condensing point has been analyzed. The steam condensate from HRU gases is offered as heat system make-up water after degasification. The cost-effectiveness analysis of HRU installation behind the Samara CHP BKZ-420-140 NGM steam boiler with consideration of heat energy and chemically purified water economy has been performed. Calculation data for boilers with different heat output has been generalized.

Increased resistance of hygroscopic condenser humidifiers when using a closed circuit suction system.

PubMed

Martinez, F J; Pietchel, S; Wise, C; Walek, J; Beamis, J F

1994-10-01

To examine a hygroscopic condenser after clinical use and to describe the interaction of a hygroscopic condenser and a closed circuit suction system used simultaneously. Prospective evaluation of hygroscopic condensers used clinically, and laboratory investigation of a hygroscopic condenser used with a closed circuit suction system. Tertiary referral centers. The hygroscopic condenser used during mechanical ventilation was removed and peak inflation pressure was measured by delivering a standard tidal volume and inspiratory flow across the isolated hygroscopic condenser while recording the peak inflation pressure. In the laboratory, four 10-mL aliquots of saline were instilled via closed circuit suction system into a test lung with fresh hygroscopic condensers (n = 15) inline. At baseline and after each instillation, the hygroscopic condenser was weighed and the peak inflation pressure was measured while in five condensers, peak expiratory flow rate was also measured. In these five devices, hygroscopic condenser resistance was measured with 100 L/min of constant gas flow while measuring the pressure drop across the hygroscopic condenser. In 11 hygroscopic condensers used for 27.5 +/- 11.9 hrs with no closed circuit suction system, the peak inflation pressure was 3.74 +/- 0.58 cm H2O. In the laboratory, instillation of saline via closed circuit suction system was associated with an increase in hygroscopic condenser weight. Peak inflation pressure increased in a quadratic fashion with the increase in hygroscopic condenser weight, while peak expiratory flow rate decreased in a linear fashion. After four saline instillations, hygroscopic condenser resistance increased from 5.66 +/- 0.31 to 13.9 +/- 2.42 cm H2O/L/sec. Clinical use of a hygroscopic condenser alone is not associated with a significant increase in peak inflation pressure. We caution the use of a hygroscopic condenser and a closed circuit suction system simultaneously, as an increase in hygroscopic condenser resistance may develop and may be poorly tolerated in patients with marginal ventilatory reserve.

Hierarchical parallelisation of functional renormalisation group calculations - hp-fRG

NASA Astrophysics Data System (ADS)

Rohe, Daniel

2016-10-01

The functional renormalisation group (fRG) has evolved into a versatile tool in condensed matter theory for studying important aspects of correlated electron systems. Practical applications of the method often involve a high numerical effort, motivating the question in how far High Performance Computing (HPC) can leverage the approach. In this work we report on a multi-level parallelisation of the underlying computational machinery and show that this can speed up the code by several orders of magnitude. This in turn can extend the applicability of the method to otherwise inaccessible cases. We exploit three levels of parallelisation: Distributed computing by means of Message Passing (MPI), shared-memory computing using OpenMP, and vectorisation by means of SIMD units (single-instruction-multiple-data). Results are provided for two distinct High Performance Computing (HPC) platforms, namely the IBM-based BlueGene/Q system JUQUEEN and an Intel Sandy-Bridge-based development cluster. We discuss how certain issues and obstacles were overcome in the course of adapting the code. Most importantly, we conclude that this vast improvement can actually be accomplished by introducing only moderate changes to the code, such that this strategy may serve as a guideline for other researcher to likewise improve the efficiency of their codes.

(Short articles on energy conservation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodges, L.

1985-01-01

The following short articles are reprinted after being published in the Tri-County Times, Slater, Iowa, by Laurent Hodges of the Iowa State University Energy Extension Service: water power; small hydroelectric plants; condensation problems (three parts); energy quiz and answers; the airtight drywall approach; benefits of natural lighting; energy and Iowa's building code; heating, water heating and cooling costs in Iowa; the cost of keeping cool; and reducing the cost of keeping cool. (DLC)

Substituted polyacetylene separation membrane

DOEpatents

Pinnau, I.; Morisato, Atsushi

1998-01-13

A separation membrane is described which is useful for gas separation, particularly separation of C{sub 2+} hydrocarbons from natural gas. The invention encompasses the membrane itself, methods of making it and processes for using it. The membrane comprises a polymer having repeating units of a hydrocarbon-based, disubstituted polyacetylene, having the general formula shown in the accompanying diagram, wherein R{sub 1} is chosen from the group consisting of C{sub 1}-C{sub 4} alkyl and phenyl, and wherein R{sub 2} is chosen from the group consisting of hydrogen and phenyl. In the most preferred embodiment, the membrane comprises poly(4-methyl-2-pentyne) [PMP]. The membrane exhibits good chemical resistance and has super-glassy properties with regard to separating certain large, condensable permeant species from smaller, less-condensable permeant species. The membranes may also be useful in other fluid separations. 4 figs.

Universal Themes of Bose-Einstein Condensation

NASA Astrophysics Data System (ADS)

Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.

2017-04-01

Foreword; List of contributors; Preface; Part I. Introduction: 1. Universality and Bose-Einstein condensation: perspectives on recent work D. W. Snoke, N. P. Proukakis, T. Giamarchi and P. B. Littlewood; 2. A history of Bose-Einstein condensation of atomic hydrogen T. Greytak and D. Kleppner; 3. Twenty years of atomic quantum gases: 1995-2015 W. Ketterle; 4. Introduction to polariton condensation P. B. Littlewood and A. Edelman; Part II. General Topics: Editorial notes; 5. The question of spontaneous symmetry breaking in condensates D. W. Snoke and A. J. Daley; 6. Effects of interactions on Bose-Einstein condensation R. P. Smith; 7. Formation of Bose-Einstein condensates M. J. Davis, T. M. Wright, T. Gasenzer, S. A. Gardiner and N. P. Proukakis; 8. Quenches, relaxation and pre-thermalization in an isolated quantum system T. Langen and J. Schmiedmayer; 9. Ultracold gases with intrinsic scale invariance C. Chin; 10. Berezinskii-Kosterlitz-Thouless phase of a driven-dissipative condensate N. Y. Kim, W. H. Nitsche and Y. Yamamoto; 11. Superfluidity and phase correlations of driven dissipative condensates J. Keeling, L. M. Sieberer, E. Altman, L. Chen, S. Diehl and J. Toner; 12. BEC to BCS crossover from superconductors to polaritons A. Edelman and P. B. Littlewood; Part III. Condensates in Atomic Physics: Editorial notes; 13. Probing and controlling strongly correlated quantum many-body systems using ultracold quantum gases I. Bloch; 14. Preparing and probing chern bands with cold atoms N. Goldman, N. R. Cooper and J. Dalibard; 15. Bose-Einstein condensates in artificial gauge fields L. J. LeBlanc and I. B. Spielman; 16. Second sound in ultracold atomic gases L. Pitaevskii and S. Stringari; 17. Quantum turbulence in atomic Bose-Einstein condensates N. G. Parker, A. J. Allen, C. F. Barenghi and N. P. Proukakis; 18. Spinor-dipolar aspects of Bose-Einstein condensation M. Ueda; Part IV. Condensates in Condensed Matter Physics: Editorial notes; 19. Bose-Einstein condensation of photons and grand-canonical condensate fluctuations J. Klaers and M. Weitz; 20. Laser operation and Bose-Einstein condensation: analogies and differences A. Chiocchetta, A. Gambassi and I. Carusotto; 21. Vortices in resonant polariton condensates in semiconductor microcavities D. N. Krizhanovskii, K. Guda, M. Sich, M. S. Skolnick, L. Dominici and D. Sanvitto; 22. Optical control of polariton condensates G. Christmann, P. G. Savvidis and J. J. Baumberg; 23. Disorder, synchronization and phase-locking in non-equilibrium Bose-Einstein condensates P. R. Eastham and B. Rosenow; 24. Collective topological excitations in 1D polariton quantum fluids H. Terças, D. D. Solnyshkov and G. Malpuech; 25. Microscopic theory of Bose-Einstein condensation of magnons at room temperature H. Salman, N. G. Berloff and S. O. Demokritov; 26. Spintronics and magnon Bose-Einstein condensation R. A. Duine, A. Brataas, S. A. Bender and Y. Tserkovnyak; 27. Spin-superfluidity and spin-current mediated non-local transport H. Chen and A. H. MacDonald; 28. Bose-Einstein condensation in quantum magnets C. Kollath, T. Giamarchi and C. Rüegg; Part V. Condensates in Astrophysics and Cosmology: Editorial notes; 29. Bose-Einstein condensates in neutron stars C. J. Pethick, T. Schäfer and A. Schwenk; 30. A simulated cosmological metric: the superfluid 3He condensate G. R. Pickett; 31. Cosmic axion Bose-Einstein condensation N. Banik and P. Sikivie; 32. Graviton BECs: a new approach to quantum gravity G. Dvali and C. Gomez; Universal Bose-Einstein condensation workshop; Index.

Canonical coordinates and meson spectra for scalar deformed Script N = 4 SYM from the AdS/CFT correspondence

NASA Astrophysics Data System (ADS)

Shock, Jonathan P.

2006-10-01

Two points on the Coulomb branch of Script N = 4 super Yang Mills are investigated using their supergravity duals. By switching on condensates for the scalars in the Script N = 4 multiplet with a form which preserves a subgroup of the original R-symmetry, disk and sphere configurations of D3-branes are formed in the dual supergravity background. The analytic, canonical metric for these geometries is formulated and the singularity structure is studied. Quarks are introduced into the corresponding field theories using D7-brane probes and the meson spectrum is calculated. For one of the condensate configurations, a mass gap is found and shown analytically to be present in the massless limit. It is also found that there is a stepped spectrum with eigenstate degeneracy in the limit of small quark masses and this result is shown analytically. In the second, similar deformation it is necessary to understand the full D3-D7 brane interaction to study the limit of small quark masses. For quark masses larger than the condensate scale the spectrum is calculated and shown to be discrete as expected.

Synthesis of sterically hindered enamides via a Ti-mediated condensation of amides with aldehydes and ketones.

PubMed

Genovino, Julien; Lagu, Bharat; Wang, Yaping; Touré, B Barry

2012-07-07

The first TiCl(4)-mediated condensation of secondary amides with aldehydes and ketones has been achieved. The reaction proceeds at room temperature and is complete within 5 h in most cases. The optimized procedure used 5 equiv of an amine base hinting that the in situ activation of both the amide and the Lewis acid is required. The reaction affords polysubstituted (E)-enamides.

Analysis of quantum error-correcting codes: Symplectic lattice codes and toric codes

NASA Astrophysics Data System (ADS)

Harrington, James William

Quantum information theory is concerned with identifying how quantum mechanical resources (such as entangled quantum states) can be utilized for a number of information processing tasks, including data storage, computation, communication, and cryptography. Efficient quantum algorithms and protocols have been developed for performing some tasks (e.g. , factoring large numbers, securely communicating over a public channel, and simulating quantum mechanical systems) that appear to be very difficult with just classical resources. In addition to identifying the separation between classical and quantum computational power, much of the theoretical focus in this field over the last decade has been concerned with finding novel ways of encoding quantum information that are robust against errors, which is an important step toward building practical quantum information processing devices. In this thesis I present some results on the quantum error-correcting properties of oscillator codes (also described as symplectic lattice codes) and toric codes. Any harmonic oscillator system (such as a mode of light) can be encoded with quantum information via symplectic lattice codes that are robust against shifts in the system's continuous quantum variables. I show the existence of lattice codes whose achievable rates match the one-shot coherent information over the Gaussian quantum channel. Also, I construct a family of symplectic self-dual lattices and search for optimal encodings of quantum information distributed between several oscillators. Toric codes provide encodings of quantum information into two-dimensional spin lattices that are robust against local clusters of errors and which require only local quantum operations for error correction. Numerical simulations of this system under various error models provide a calculation of the accuracy threshold for quantum memory using toric codes, which can be related to phase transitions in certain condensed matter models. I also present a local classical processing scheme for correcting errors on toric codes, which demonstrates that quantum information can be maintained in two dimensions by purely local (quantum and classical) resources.

Linear actuation using milligram quantities of CL-20 and TAGDNAT.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snedigar, Shane; Salton, Jonathan Robert; Tappan, Alexander Smith

2009-07-01

There are numerous applications for small-scale actuation utilizing pyrotechnics and explosives. In certain applications, especially when multiple actuation strokes are needed, or actuator reuse is required, it is desirable to have all gaseous combustion products with no condensed residue in the actuator cylinder. Toward this goal, we have performed experiments on utilizing milligram quantities of high explosives to drive a millimeter-diameter actuator with a stroke of 30 mm. Calculations were performed to select proper material quantities to provide 0.5 J of actuation energy. This was performed utilizing the thermochemical code Cheetah to calculate the impetus for numerous propellants and tomore » select quantities based on estimated efficiencies of these propellants at small scales. Milligram quantities of propellants were loaded into a small-scale actuator and ignited with an ignition increment and hot wire ignition. Actuator combustion chamber pressure was monitored with a pressure transducer and actuator stroke was monitored using a laser displacement meter. Total actuation energy was determined by calculating the kinetic energy of reaction mass motion against gravity. Of the materials utilized, the best performance was obtained with a mixture of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and bis-triaminoguanidinium(3,3{prime}dinitroazotriazolate) (TAGDNAT).« less

21 CFR 177.2450 - Polyamide-imide resins.

Code of Federal Regulations, 2014 CFR

2014-04-01

... polyamide-imide resins are derived from the condensation reaction of substantially equimolar parts of.... 31957-38-7) derived from the condensation reaction of equimolar parts of benzoyl chloride-3,4...

Mars atmospheric CO2 condensation above the north and south poles as revealed by radio occultation, climate sounder, and laser ranging observations

NASA Astrophysics Data System (ADS)

Hu, Renyu; Cahoy, Kerri; Zuber, Maria T.

2012-07-01

We study the condensation of CO2 in Mars' atmosphere using temperature profiles retrieved from radio occultation measurements from Mars Global Surveyor (MGS) as well as the climate sounding instrument onboard the Mars Reconnaissance Orbiter (MRO), and detection of reflective clouds by the MGS Mars Orbiter Laser Altimeter (MOLA). We find 11 events in 1999 where MGS temperature profiles indicate CO2 condensation and MOLA simultaneously detects reflective clouds. We thus provide causal evidence that MOLA non-ground returns are associated with CO2 condensation, which strongly indicates their nature being CO2 clouds. The MGS and MRO temperature profiles together reveal the seasonal expansion and shrinking of the area and the vertical extent of atmospheric saturation. The occurrence rate of atmospheric saturation is maximized at high latitudes in the middle of winter. The atmospheric saturation in the northern polar region exhibits more intense seasonal variation than in the southern polar region. In particular, a shrinking of saturation area and thickness from LS ˜ 270° to ˜300° in 2007 is found; this is probably related to a planet-encircling dust storm. Furthermore, we integrate the condensation area and the condensation occurrence rate to estimate cumulative masses of CO2 condensates deposited onto the northern and southern seasonal polar caps. The precipitation flux is approximated by the particle settling flux which is estimated using the impulse responses of MOLA filter channels. With our approach, the total atmospheric condensation mass can be estimated from these observational data sets with average particle size as the only free parameter. By comparison with the seasonal polar cap masses inferred from the time-varying gravity of Mars, our estimates indicate that the average condensate particle radius is 8-22 μm in the northern hemisphere and 4-13 μm in the southern hemisphere. Our multi-instrument data analysis provides new constraints on modeling the global climate of Mars.

Condensed tannins: Quinone methide intermediates in procyanidin synthesis

Treesearch

Richard W. Hemingway; L. Y. Foo

1983-01-01

Proanthocyanidins (condensed tanruns) are widely distributed in plants and are found in sufficiently high concentration in some tree barks to encourage their industrial utilization. These polymers consist of flavanoid units linked through the C-4 of the pyran ring to the C-6 or C-8 carbons of the aromatic A-ring. Recent advances in the chemistry of condensed tannins...

Condenser-free contrast methods for transmitted-light microscopy

PubMed Central

WEBB, K F

2015-01-01

Phase contrast microscopy allows the study of highly transparent yet detail-rich specimens by producing intensity contrast from phase objects within the sample. Presented here is a generalized phase contrast illumination schema in which condenser optics are entirely abrogated, yielding a condenser-free yet highly effective method of obtaining phase contrast in transmitted-light microscopy. A ring of light emitting diodes (LEDs) is positioned within the light-path such that observation of the objective back focal plane places the illuminating ring in appropriate conjunction with the phase ring. It is demonstrated that true Zernike phase contrast is obtained, whose geometry can be flexibly manipulated to provide an arbitrary working distance between illuminator and sample. Condenser-free phase contrast is demonstrated across a range of magnifications (4–100×), numerical apertures (0.13–1.65NA) and conventional phase positions. Also demonstrated is condenser-free darkfield microscopy as well as combinatorial contrast including Rheinberg illumination and simultaneous, colour-contrasted, brightfield, darkfield and Zernike phase contrast. By providing enhanced and arbitrary working space above the preparation, a range of concurrent imaging and electrophysiological techniques will be technically facilitated. Condenser-free phase contrast is demonstrated in conjunction with scanning ion conductance microscopy (SICM), using a notched ring to admit the scanned probe. The compact, versatile LED illumination schema will further lend itself to novel next-generation transmitted-light microscopy designs. The condenser-free illumination method, using rings of independent or radially-scanned emitters, may be exploited in future in other electromagnetic wavebands, including X-rays or the infrared. PMID:25226859

Effect of feeding legumes containing condensed tannins with orchardgrass on ruminal fermentation and methane production in continuous culture

USDA-ARS?s Scientific Manuscript database

Developing feeding strategies that allow farmers to reduce methane (CH4) emissions from livestock is gaining interest worldwide. Legumes containing condensed tannins (CT) have been shown to decrease enteric CH4 in ruminants; however, research is lacking on how increased CT levels affect ruminal ferm...

Condensation Time of the Solar Nebula from Extinct 129I in Primitive Meteorites

PubMed Central

Lewis, Roy S.; Anders, Edward

1975-01-01

Mineral separates from five carbonaceous chondrites were dated by extinct 16 million year 129I, in an attempt to establish the condensation time of the solar nebula. Two Fe3O4 or Fe3O4-FeS samples from the Murchison and Orgueil meteorites are older than any other material dated thus far, and apparently formed within 2 × 105 years of each other. The great age, close isochronism, and primitive nature of the samples suggest that the event recorded was the condensation stage of the solar nebula. It provides a suitable zero point for the chronology of the early solar system. The 129I/127I ratio during condensation of the nebula was (1.46 ± 0.04) × 10-4. The recrystallized C4 chondrite Karoonda began to retain 129Xe 1.8 ± 0.5 million years after the above event. This short cooling time implies rapid aceretion (≤1 million years) and a shallow origin (≤10 km) below the surface of its parent body. Images PMID:16592213

Recovery of Water from Boiler Flue Gas Using Condensing Heat Exchangers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levy, Edward; Bilirgen, Harun; DuPont, John

2011-03-31

Most of the water used in a thermoelectric power plant is used for cooling, and DOE has been focusing on possible techniques to reduce the amount of fresh water needed for cooling. DOE has also been placing emphasis on recovery of usable water from sources not generally considered, such as mine water, water produced from oil and gas extraction, and water contained in boiler flue gas. This report deals with development of condensing heat exchanger technology for recovering moisture from flue gas from coal-fired power plants. The report describes: • An expanded data base on water and acid condensation characteristicsmore » of condensing heat exchangers in coal-fired units. This data base was generated by performing slip stream tests at a power plant with high sulfur bituminous coal and a wet FGD scrubber and at a power plant firing highmoisture, low rank coals. • Data on typical concentrations of HCl, HNO{sub 3} and H{sub 2}SO{sub 4} in low temperature condensed flue gas moisture, and mercury capture efficiencies as functions of process conditions in power plant field tests. • Theoretical predictions for sulfuric acid concentrations on tube surfaces at temperatures above the water vapor dewpoint temperature and below the sulfuric acid dew point temperature. • Data on corrosion rates of candidate heat exchanger tube materials for the different regions of the heat exchanger system as functions of acid concentration and temperature. • Data on effectiveness of acid traps in reducing sulfuric acid concentrations in a heat exchanger tube bundle. • Condensed flue gas water treatment needs and costs. • Condensing heat exchanger designs and installed capital costs for full-scale applications, both for installation immediately downstream of an ESP or baghouse and for installation downstream of a wet SO{sub 2} scrubber. • Results of cost-benefit studies of condensing heat exchangers.« less

A Comparison of the Tube-Side Performance of Enhanced Heat Transfer Tubing for Naval Condensers.

DTIC Science & Technology

1982-12-01

AD-A126 938 A COMPARISON OF THE TUBE-SIDE PERFORMANCE OF ENHANCEDAD 12693! HEAT TRANSFER TUBING FOR NAVAL CONDENSERS U) NAVAL POSTGRADUATE SCHOOD...COMPARISON OF THE TUBE-SIDE PERFORMANCE OF ENHANCED HEAT TRANSFER TUBING FOR NAVAL CONDENSERS by Ronald Keith Alexander December 1982 Thesis Advisor: P. J...Comparison of the Tube-Side Master’s Thesis Performance of Enhanced Heat Transfer Pma""nG kpA lne Tubing for Naval Condensers ~PU~UN 4 iotwug 1. AU Y..NW41 6

An Experimental Apparatus to Study Enhanced Condensation Heat Transfer of Steam on Horizontal Tubes.

DTIC Science & Technology

1982-06-01

6-inches in diam- eter and 18-inches long and provides for condensing all excess steam. Two helically wound -oils of 3/8-inch copper tubing,- one 5 1...ml--13E lmoI EE EEEM NAVAL POSTGRADUATE SCHOOL Monterey, California SP27 1982 F THESIS AN EXPERIMENTAL APPARATUS TO STUDY ENHANCED CONDENSATION HEAT...Enhanced Condensation Heat Transfer June 1982 of Steam on Horizontal. Tubes & 081OWN ow,. NeWOormueT -. AUT@,a~4. CONTRACT ORt GOAMT NtUpMORA~e Raymond

Ultra-cold molecules in an atomic Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Wynar, Roahn Helden

2000-08-01

This thesis is about photoassociation of Bose-condensed 87Rb. Most importantly we report that state selected 87Rb2 molecules were created at rest in a condensate of 87Rb using two-photon photoassociation. Additionally, we have identified three weakly bound states of the 87Rb2 S+u3 , potential for the |1, -1> + |1, - 1> collisional channel. The binding energies of these states are 529.4 +/- .07, 636.0094 +/- .0012, and 24.24 +/- .01 MHz respectively. We have also carried out a detailed study of the density dependence of the shift and width of the two-photon lineshape. This shift and width is modeled using the theory of Bohn and Julienne [34] and in addition to the precise measurement of binding energy we also report the first measurement of an atom molecule scattering length, aam, which we conclude is -180 +/- 150 a0, and the inelastic collision rate, Kinel < 8 × 10-11 cm-3/s. Stimulated Raman free bound coupling in an atomic Bose- Einstein condensate may lead to the formation of a molecular condensate. In order to evaluate this possibility we present a many-body quantum mean field theory of a Bose-Einstein condensate that includes a density dependent coherent coupling between atoms and molecules. This theory yields two coupled equations, one for the evolution of atomic condensate amplitude and one for the evolution of molecular condensate amplitude. The nature of the atomic-molecular condensate evolution is shown to depend on six, model parameters including the coherent coupling, given by cn . The other five parameters can be interpreted as light-shifts and incoherent loss rates. We present a calculation intended to estimate the values of these six parameters for the 87Rb - 87Rb 2 system. Based on the results of this calculation we identify two locations in the 87Rb2 spectrum where coherent transfer of population from atomic condensate to molecular condensate is plausible. Finally, we examine the credibility of the theoretical model used to estimate the six parameters used by the mean field theory. By comparing the measured Stark shifts of two-color resonances with predictions based on our theoretical model we conclude that the model is satisfactory for the v = 37 level of the S+u3 potential. This work also describes the experimental details of stabilizing a Coherent 899-01 Ti:Saphire laser and the experimental methods important to executing photoassociation in a time-averaged-orbiting potential (TOP) trap.

17. MIDBASEMENT, LOOKING NORTHEAST AT WEST END OF THE CONDENSATE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. MID-BASEMENT, LOOKING NORTHEAST AT WEST END OF THE CONDENSATE UNIT FOR TURBINE #4 - Portland General Electric Company, Turbine Building, 1841 Southeast Water Street, Portland, Multnomah County, OR

Plant polyketide synthases: a chalcone synthase-type enzyme which performs a condensation reaction with methylmalonyl-CoA in the biosynthesis of C-methylated chalcones.

PubMed

Schröder, J; Raiber, S; Berger, T; Schmidt, A; Schmidt, J; Soares-Sello, A M; Bardshiri, E; Strack, D; Simpson, T J; Veit, M; Schröder, G

1998-06-09

Heterologous screening of a cDNA library from Pinusstrobus seedlings identified clones for two chalcone synthase (CHS) related proteins (PStrCHS1 and PStrCHS2, 87.6% identity). Heterologous expression in Escherichia coli showed that PStrCHS1 performed the typical CHS reaction, that it used starter CoA-esters from the phenylpropanoid pathway, and that it performed three condensation reactions with malonyl-CoA, followed by the ring closure to the chalcone. PstrCHS2 was completely inactive with these starters and also with linear CoA-esters. Activity was detected only with a diketide derivative (N-acetylcysteamine thioester of 3-oxo-5-phenylpent-4-enoic acid) that corresponded to the CHS reaction intermediate postulated after the first condensation reaction. PstrCHS2 performed only one condensation, with 6-styryl-4-hydroxy-2-pyrone derivatives as release products. The enzyme preferred methylmalonyl-CoA against malonyl-CoA, if only methylmalonyl-CoA was available. These properties and a comparison with the CHS from Pinus sylvestris suggested for PstrCHS2 a special function in the biosynthesis of secondary products. In contrast to P. sylvestris, P. strobus contains C-methylated chalcone derivatives, and the methyl group is at the position predicted from a chain extension with methylmalonyl-CoA in the second condensation of the biosynthetic reaction sequence. We propose that PstrCHS2 specifically contributes the condensing reaction with methylmalonyl-CoA to yield a methylated triketide intermediate. We discuss a model that the biosynthesis of C-methylated chalcones represents the simplest example of a modular polyketide synthase.

40 CFR 60.281 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... wood in white liquor, and associated flash tank(s), blow tank(s), chip steamer(s), and condenser(s). (e... condenser(s) and hotwell(s) used to concentrate the spent cooking liquid that is separated from the pulp... calcium oxide. (o) Condensate stripper system means a column, and associated condensers, used to strip...

An evaluation of strategies to control noise from air conditioning and refrigeration condensing units

NASA Astrophysics Data System (ADS)

Durden, G. L.; Myers, J. O.; Towers, T. A.; Dickman, D. M.

1981-12-01

Noise from air conditioning and refrigeration condensing units is investigated. The practical aspects of attempting to implement innovative approaches are emphasized. These included: (1) sample selection, (2) noise measurement survey, (3) implementation of aggressive abatement procedures, (4) development and use of a screening graph for determining acceptability of sound rated outdoor unitary equipment, (5) incorporation of noise control considerations, (6) exploration of an operatinal curfew, and (7) development of an incentive/information program.

Utilization of air conditioner condenser as water heater in an effort to energy conservation

NASA Astrophysics Data System (ADS)

Sonawan, Hery; Saputro, Panji; Kurniawan, Iden Muhtar

2018-04-01

This paper presents an experimental study of utilization of air conditioner condenser as water heater. Modification of existing air conditioner system is an effort to harvest waste heat energy from condenser. Modification is conducted in order to test the system into two mode tests, first mode with one condenser and second mode with two condensers. Harvesting the waste heat from condenser needs a theoretical and practice study to see how much the AC performance changes if modifications are made. It should also be considered how the technique of harvesting waste heat for water heating purposes. From the problem, this paper presents a comparison between AC performance before and after modification. From the experiment, an increase in compressor power consumption is 4.3% after adding a new condenser. The hot water temperature is attained to 69 °C and ready for warm bath. The increase in power consumption is not too significant compared to the attainable hot water temperature. Also seen that the value of condenser Performance Factor increase from 5.8 to 6.25 or by 7.8%.

Inhibition of α-Amylases by Condensed and Hydrolysable Tannins: Focus on Kinetics and Hypoglycemic Actions

PubMed Central

Kato, Camila Gabriel; Gonçalves, Geferson de Almeida; Peralta, Rosely Aparecida; Seixas, Flavio Augusto Vicente; de Sá-Nakanishi, Anacharis Babeto; Bracht, Lívia; Comar, Jurandir Fernando

2017-01-01

The aim of the present study was to compare the in vitro inhibitory effects on the salivary and pancreatic α-amylases and the in vivo hypoglycemic actions of the hydrolysable tannin from Chinese natural gall and the condensed tannin from Acacia mearnsii. The human salivary α-amylase was more strongly inhibited by the hydrolysable than by the condensed tannin, with the concentrations for 50% inhibition (IC50) being 47.0 and 285.4 μM, respectively. The inhibitory capacities of both tannins on the pancreatic α-amylase were also different, with IC50 values being 141.1 μM for the hydrolysable tannin and 248.1 μM for the condensed tannin. The kinetics of the inhibition presented complex patterns in that for both inhibitors more than one molecule can bind simultaneously to either the free enzyme of the substrate-complexed enzyme (parabolic mixed inhibition). Both tannins were able to inhibit the intestinal starch absorption. Inhibition by the hydrolysable tannin was concentration-dependent, with 53% inhibition at the dose of 58.8 μmol/kg and 88% inhibition at the dose of 294 μmol/kg. For the condensed tannin, inhibition was not substantially different for doses between 124.4 μmol/kg (49%) and 620 μmol/kg (57%). It can be concluded that both tannins, but especially the hydrolysable one, could be useful in controlling the postprandial glycemic levels in diabetes. PMID:28589038

Design characteristics of a heat pipe test chamber

NASA Technical Reports Server (NTRS)

Baker, Karl W.; Jang, J. Hoon; Yu, Juin S.

1992-01-01

LeRC has designed a heat pipe test facility which will be used to provide data for validating heat pipe computer codes. A heat pipe test chamber that uses helium gas for enhancing heat transfer was investigated. The conceptual design employs the technique of guarded heating and guarded cooling to facilitate accurate measurements of heat transfer rates to the evaporator and from the condenser. The design parameters are selected for a baseline heat pipe made of stainless steel with an inner diameter of 38.10 mm and a wall thickness of 1.016 mm. The heat pipe operates at a design temperature of 1000 K with an evaporator radial heat flux of 53 W/sq. cm.

Measurement of carbon condensates using small-angle x-ray scattering during detonation of high explosives

NASA Astrophysics Data System (ADS)

Willey, T. M.; Bagge-Hansen, M.; Lauderbach, L.; Hodgin, R.; Hansen, D.; May, C.; van Buuren, T.; Dattelbaum, D. M.; Gustavsen, R. L.; Watkins, E. B.; Firestone, M. A.; Jensen, B. J.; Graber, T.; Bastea, S.; Fried, L.

2017-01-01

The lack of experimental validation for processes occurring at sub-micron length scales on time scales ranging from nanoseconds to microseconds hinders detonation model development. Particularly, quantification of late-time energy release requires measurement of carbon condensation kinetics behind detonation fronts. A new small-angle x-ray scattering (SAXS) endstation has been developed for use at The Dynamic Compression Sector to observe carbon condensation during detonation. The endstation and beamline demonstrate unprecedented fidelity; SAXS profiles can be acquired from single x-ray pulses, which in 24-bunch mode are about 80 ps in duration and arrive every 153.4 ns. This paper presents both the current temporal capabilities of this beamline, and the ability to distinguish different carbon condensate morphologies as they form behind detonation fronts. To demonstrate temporal capabilities, three shots acquired during detonation of hexanitrostilbene (HNS) are interleaved to show the evolution of the SAXS in about 50 ns steps. To show fidelity of the SAXS, the scattering from carbon condensates at several hundred nanoseconds varies with explosive: scattering from HNS is consistent with a complex morphology that we assert is associated with sp2 carbon., while Comp B scattering is consistent with soots containing three-dimensional diamond nanoparticles.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbary, Lawrence D.; Perkins, Laura L.; Serino, Roland

The team led by Dow Corning collaborated to increase the thermal performance of exterior insulation and finishing systems (EIFS) to reach R-40 performance meeting the needs for high efficiency insulated walls. Additionally, the project helped remove barriers to using EIFS on retrofit commercial buildings desiring high insulated walls. The three wall systems developed within the scope of this project provide the thermal performance of R-24 to R-40 by incorporating vacuum insulation panels (VIPs) into an expanded polystyrene (EPS) encapsulated vacuum insulated sandwich element (VISE). The VISE was incorporated into an EIFS as pre-engineered insulation boards. The VISE is installed usingmore » typical EIFS details and network of trained installers. These three wall systems were tested and engineered to be fully code compliant as an EIFS and meet all of the International Building Code structural, durability and fire test requirements for a code compliant exterior wall cladding system. This system is being commercialized under the trade name Dryvit® Outsulation® HE system. Full details, specifications, and application guidelines have been developed for the system. The system has been modeled both thermally and hygrothermally to predict condensation potential. Based on weather models for Baltimore, MD; Boston, MA; Miami, FL; Minneapolis, MN; Phoenix, AZ; and Seattle, WA; condensation and water build up in the wall system is not a concern. Finally, the team conducted a field trial of the system on a building at the former Brunswick Naval Air Station which is being redeveloped by the Midcoast Regional Redevelopment Authority (Brunswick, Maine). The field trial provided a retrofit R-30 wall onto a wood frame construction, slab on grade, 1800 ft2 building, that was monitored over the course of a year. Simultaneous with the façade retrofit, the building’s windows were upgraded at no charge to this program. The retrofit building used 49% less natural gas during the winter of 2012 compared to previous winters. This project achieved its goal of developing a system that is constructible, offers protection to the VIPs, and meets all performance targets established for the project.« less

Submicron Dropwise Condensation under Superheated and Rarefied Vapor Condition

PubMed Central

Anand, Sushant; Son, Sang Young

2010-01-01

Phase change accompanying conversion of a saturated or superheated vapor in presence of subcooled surfaces is one of the most common occurring phenomena in nature. The mode of phase change which follows such a transformation is dependent upon surface properties like as of contact angle and thermodynamic conditions of the system. In present studies, an experimental approach is used to study the physics behind droplet growth on a partially wetting surface. Superheated vapor at low pressures of 4–5 torr was condensed on subcooled silicon surface with static contact angle as of 60° in absence of non-condensable gases, and the condensation process monitored using Environmental Scanning Electron Microscope (ESEM) with submicroscopic spatial resolution. The condensation process was analyzed in the form of size growth of isolated droplets for before a coalescence event ended the regime of single droplet growth. Droplet growth obtained as a function of time reveals that the rate of growth decreases as the droplet increases in size. This behavior is indicative of an overall droplet growth law existing over larger time scales of which the current observations in their brief time intervals could be fitted in. A theoretical model based on kinetic theory further support the experimental observations indicating a mechanism where growth occurs by interfacial mass transport directly on condensing droplet surface. Evidence was also found which establishes the presence of submicroscopic droplets nucleating and growing in between microscopic droplets for partially wetting case. PMID:20942412

Posttest REALP4 analysis of LOFT experiment L1-3A

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, J.R.; Holmstrom, H.L.O.

This report presents selected results of posttest RELAP4 modeling of LOFT loss-of-coolant experiment L1-3A, a double-ended isothermal cold leg break with lower plenum emergency core coolant injection. Comparisons are presented between the pretest prediction, the posttest analysis, and the experimental data. It is concluded that pressurizer modeling is important for accurately predicting system behavior during the initial portion of saturated blowdown. Using measured initial conditions rather than nominal specified initial conditions did not influence the system model results significantly. Using finer nodalization in the reactor vessel improved the prediction of the system pressure history by minimizing steam condensation effects. Unequalmore » steam condensation between the downcomer and core volumes appear to cause the manometer oscillations observed in both the pretest and posttest RELAP4 analysis.« less

Analysis and Modeling of a Two-Phase Jet Pump of a Flow Boiling Test Facility for Aerospace Applications

NASA Technical Reports Server (NTRS)

Sherif, S. A.; Steadham, Justin M.

1996-01-01

Jet pumps are devices capable of pumping fluids to a higher pressure employing a nozzle/diffuser/mixing chamber combination. A primary fluid is usually allowed to pass through a converging-diverging nozzle where it can accelerate to supersonic speeds at the nozzle exit. The relatively high kinetic energy that the primary fluid possesses at the nozzle exit is accompanied by a low pressure region in order to satisfy Bernoulli's equation. The low pressure region downstream of the nozzle exit permits a secondary fluid to be entrained into and mixed with the primary fluid in a mixing chamber located downstream of the nozzle. Several combinations may exist in terms of the nature of the primary and secondary fluids in so far as whether they are single or two-phase fluids. Depending on this, the jet pump may be classified as gas/gas, gas/liquid, liquid/liquid, two-phase/liquid, or similar combinations. The mixing chamber serves to create a homogeneous single-phase or two-phase mixture which enters a diffuser where the high kinetic energy of the fluid is converted into pressure energy. If the fluid mixture entering the diffuser is in the supersonic flow regime, a normal shock wave usually develops inside the diffuser. If the fluid mixture is one that can easily change phase, a condensation shock would normally develop. Because of the overall rise in pressure in the diffuser as well as the additional rise in pressure across the shock layer, condensation becomes more likely. Associated with the pressure rise across the shock is a velocity reduction from the supersonic to the subsonic range. If the two-phase flow entering the diffuser is predominantly gaseous with liquid droplets suspended in it, it will transform into a predominantly liquid flow containing gaseous bubbles (bubbly flow) somewhere in the diffuser. While past researchers have been able to model the two-phase flow jet pump using the one-dimensional assumption with no shock waves and no phase change, there is no research known to the authors apart from that of Anand (1992) which accounted for condensation shocks. One of the objectives of this research effort is to develop a comprehensive model in which the effects of phase slip and inter-phase heat transfer as well as the wall friction and shock waves are accounted for. While this modeling effort is predominantly analytical in nature and is primarily intended to provide a parametric understanding of the jet pump performance under different operating scenarios, another parallel effort employing a commercial CFD code is also implemented. The latter effort is primarily intended to model an axisymmetric counterpart of the problem in question. The viability of using the CFD code to model a two-phase flow jet pump will be assessed by attempting to recreate some of the existing performance data of similar jet pumps. The code will eventually be used to generate the jet pump performance characteristics of several scenarios involving jet pump geometries as well as flow regimes in order to be able to determine an optimum design which would be suitable for a two-phase flow boiling test facility at NASA-Marshall. Because of the extensive nature of the analytical model developed, the following section will only provide very brief highlights of it, while leaving the details to a more complete report submitted to the NASA colleague. This report will also contain some of the simulation results obtained using the CFD code.

Directed reflectivity, long life AMTEC condenser (DRC). Final report of Phase II SBIR program[Alkali Metal ThermoElectric Converter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunt, Thomas K.

The Alkali Metal Thermal to Electric Converter (AMTEC) is a static energy conversion device that operates at high thermal to electric conversion efficiencies that are essentially independent of size, have reached 19% and are expected to reach 25% to 30% in 1997. AMTEC systems have been chosen by NASA and DOE for spacecraft applications and have considerable promise for a wide variety of terrestrial applications. Reduction of parasitic heat losses in AMTEC systems related to radiative heat transfer from the hot side to the condenser can make a substantial contribution to system efficiency. Through design, analysis and the fabrication andmore » testing of cells and systems, the proposed program to develop a Directed Reflectivity Condenser (DRC) has investigated the feasibility of an improved AMTEC condenser component. Phase 1 work showed the potential for adding from 4% to 7% to overall system efficiency for identical operating conditions using the concept. A detailed thermal analysis of several DRC capped cell designs was carried out and some of the conditions under which a DRC, used as the condenser at an end cap of a cylindrical converter, can reduce thermal radiation related losses were determined. A model experimental converter was built and tested to compare DRC and planar condenser surfaces. The results of both analysis and experiment indicate that for moderate aspect ratios of a cylindrical, end condensed converter, the DRC can reduce overall thermal losses by up to 4%. The initial effort in Phase 2 extended the analysis to a novel 150 watt radial AMTEC cell design. This analysis indicated that for the effective aspect ratio of this new converter design, the system performance at the 100+ watt level was not significantly improved by use of a DRC type condenser surface. Further analyses however showed that for cylindrical, end-condensed converters, optimized for use with internal radiation shields, the use of DRC surfaces on the side walls of the converter could be more effective than on the condenser end surface itself. The experimental work in Phase 2 was intended to incorporate a DRC into this cell design and use its measured performance to refine the state-of-the-art AMTEC analytical models. Because the analysis had indicated that the new radial converter design, which may be useful for systems at the {approx} 100 watt level was not much assisted by the DRC properties, this program was redirected toward the simpler cylindrical converter design with the corner cube surfaces on the side walls. The Phase II program was proposed and planned with a funding level substantially below the maximum potentially available for Phase II programs at that time. At the time, there were two other funded government sponsored programs at AMPS for which positive results of the analyses described in this report were expected to lead to incorporation of the DRC concept into converters scheduled to be built for these programs. The programs of interest were the Air Force program titled ''Radiation Tolerant, Eclipse Compatible, Solar AMTEC System'' (F29601-99-C-0132) and the DOE/NASA Advanced Radioisotope Power System (ARPS) program. Shortly after its start, the Air Force program was canceled due to elimination of AF SBIR funds at AFRL and the ARPS program was reduced to a level that could not support introduction of novel concept testing. As a result of these two circumstances, the direct testing of the DRC concept in a full up converter was not completed in the Phase II period.« less

Quantum gas-liquid condensation in an attractive Bose gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Shun-ichiro

Gas-liquid condensation (GLC) in an attractive Bose gas is studied on the basis of statistical mechanics. Using some results in combinatorial mathematics, the following are derived. (1) With decreasing temperature, the Bose-statistical coherence grows in the many-body wave function, which gives rise to the divergence of the grand partition function prior to Bose-Einstein condensation. It is a quantum-mechanical analogue to the GLC in a classical gas (quantum GLC). (2) This GLC is triggered by the bosons with zero momentum. Compared with the classical GLC, an incomparably weaker attractive force creates it. For the system showing the quantum GLC, we discussmore » a cold helium 4 gas at sufficiently low pressure.« less

Using Intel Xeon Phi to accelerate the WRF TEMF planetary boundary layer scheme

NASA Astrophysics Data System (ADS)

Mielikainen, Jarno; Huang, Bormin; Huang, Allen

2014-05-01

The Weather Research and Forecasting (WRF) model is designed for numerical weather prediction and atmospheric research. The WRF software infrastructure consists of several components such as dynamic solvers and physics schemes. Numerical models are used to resolve the large-scale flow. However, subgrid-scale parameterizations are for an estimation of small-scale properties (e.g., boundary layer turbulence and convection, clouds, radiation). Those have a significant influence on the resolved scale due to the complex nonlinear nature of the atmosphere. For the cloudy planetary boundary layer (PBL), it is fundamental to parameterize vertical turbulent fluxes and subgrid-scale condensation in a realistic manner. A parameterization based on the Total Energy - Mass Flux (TEMF) that unifies turbulence and moist convection components produces a better result that the other PBL schemes. For that reason, the TEMF scheme is chosen as the PBL scheme we optimized for Intel Many Integrated Core (MIC), which ushers in a new era of supercomputing speed, performance, and compatibility. It allows the developers to run code at trillions of calculations per second using the familiar programming model. In this paper, we present our optimization results for TEMF planetary boundary layer scheme. The optimizations that were performed were quite generic in nature. Those optimizations included vectorization of the code to utilize vector units inside each CPU. Furthermore, memory access was improved by scalarizing some of the intermediate arrays. The results show that the optimization improved MIC performance by 14.8x. Furthermore, the optimizations increased CPU performance by 2.6x compared to the original multi-threaded code on quad core Intel Xeon E5-2603 running at 1.8 GHz. Compared to the optimized code running on a single CPU socket the optimized MIC code is 6.2x faster.

RELAP5-3D Developmental Assessment: Comparison of Versions 4.3.4i and 4.2.1i

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayless, Paul David

2015-10-01

Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code using versions 4.3.4i and 4.2.1i. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions changed between these two code versions and can be used to identify cases in which the assessment judgment may need to be changed in Volume III of the code manual. Changes to the assessment judgments made after reviewing allmore » of the assessment cases are also provided.« less

The design and development of a vapor compression refrigerator/freezer for spacelab

NASA Technical Reports Server (NTRS)

Hye, A.

1983-01-01

A computer simulation was performed to determine the design criteria for a spacelab refrigerator/freezer using the test results of a vapor compression refrigerator/freezer which flew on STS-4 without problem. It has been established to have a vapor Reynolds number over 3000 at a vapor quality of 0.2 to maintain annular boiling in the evaporator and for the condenser to have a vapor Reynolds number over 15000 at its inlet to maintain annular condensation. These two constraints will virtually eliminate the effect of gravity on the performance of the refrigerator/freezer. These results are being used to build a refrigerator/freezer which will fly in Spacelab-4 scheduled for launch in December 1985.

Substituted polyacetylene separation membrane

DOEpatents

Pinnau, Ingo; Morisato, Atsushi

1998-01-13

A separation membrane useful for gas separation, particularly separation of C.sub.2+ hydrocarbons from natural gas. The invention encompasses the membrane itself, methods of making it and processes for using it. The membrane comprises a polymer having repeating units of a hydrocarbon-based, disubstituted polyacetylene, having the general formula: ##STR1## wherein R.sub.1 is chosen from the group consisting of C.sub.1 -C.sub.4 alkyl and phenyl, and wherein R.sub.2 is chosen from the group consisting of hydrogen and phenyl. In the most preferred embodiment, the membrane comprises poly(4-methyl-2-pentyne) ›PMP!. The membrane exhibits good chemical resistance and has super-glassy properties with regard to separating certain large, condensable permeant species from smaller, less-condensable permeant species. The membranes may also be useful in other fluid separations.

Lattice stability and thermal properties of Fe2VAl and Fe2TiSn Heusler compounds

NASA Astrophysics Data System (ADS)

Shastri, Shivprasad S.; Pandey, Sudhir K.

2018-04-01

Fe2VAl and Fe2TiSn are two full-Heusler compounds with non-magnetic ground states. They have application as potential thermoelectric materials. Along with first-principles electronic structure calculations, phonon calculation is one of the important tools in condensed matter physics and material science. Phonon calculations are important in understanding mechanical properties, thermal properties and phase transitions of periodic solids. A combination of electronic structure code and phonon calculation code - phonopy is employed in this work. The vibrational spectra, phonon DOS and thermal properties are studied for these two Heusler compounds. Two compounds are found to be dynamically stable with absence of negative frequencies (energy) in the phonon band structure.

Highly efficient and recyclable basic mesoporous zeolite catalyzed condensation, hydroxylation, and cycloaddition reactions.

PubMed

Sarmah, Bhaskar; Satpati, Biswarup; Srivastava, Rajendra

2017-05-01

Crystalline mesoporous ZSM-5 zeolite was prepared in the presence of 1,4-diazabicyclo[2.2.2]octane derived multi-cationic structure directing agent. The calcined form of the mesoprous zeolite was treated with NH 4 OH to obtain basic mesoporous ZSM-5. Catalyst was characterized by the complementary combination of X-ray diffraction, N 2 -adsorption, electron microscopes, and temperature programme desorption techniques. Catalytic activity of the basic mesoporous ZSM-5 was systematically assessed using Knoevenagel condensation reaction for the synthesis a wide range of substituted styrene. Applications of the catalyst were investigated in the benzamide hydroxylation for the synthesis of carbinolamides and one-pot, multi-component condensation reaction for the synthesis of naphthopyrans. Finally, the catalyst was evaluated in the cycloaddition of CO 2 to epoxide for the synthesis of cyclic carbonates. Recycling study shows that no significant decrease in the catalytic activity was observed after five recycles. Copyright © 2017. Published by Elsevier Inc.

PEG and mPEG-anthracene induce DNA condensation and particle formation.

PubMed

Froehlich, E; Mandeville, J S; Arnold, D; Kreplak, L; Tajmir-Riahi, H A

2011-08-18

In this study, we investigated the binding of DNA with poly(ethylene glycol) (PEG) of different sizes and compositions such as PEG 3350, PEG 6000, and mPEG-anthracene in aqueous solution at physiological conditions. The effects of size and composition on DNA aggregation and condensation as well as conformation were determined using Fourier transform infrared (FTIR), UV-visible, CD, fluorescence spectroscopic methods and atomic force microscopy (AFM). Structural analysis showed moderate complex formation for PEG 3350 and PEG 6000 and weaker interaction for mPE-anthracene-DNA adducts with both hydrophilic and hydrophobic contacts. The order of ± stability of the complexes formed is K(PEG 6000) = 1.5 (±0.4) × 10(4) M(-1) > K(PEG 3350) = 7.9 (±1) × 10(3) M(-1) > K(m(PEG-anthracene))= 3.6 (±0.8) × 10(3) M(-1) with nearly 1 bound PEG molecule per DNA. No B-DNA conformational changes were observed, while DNA condensation and particle formation occurred at high PEG concentration.

Effect of Fodder Tree Species with Condensed Tannin Contents on In vitro Methane Production

PubMed Central

Vázquez, Ernestina Gutiérrez; Medina, Leonardo Hernández; Benavides, Liliana Márquez; Caratachea, Aureliano Juárez; Razo, Guillermo Salas; Burgos, Armin Javier Ayala; Rodríguez, Ruy Ortiz

2016-01-01

The objective was to evaluate the effect of fodder tree species (FTS) with condensed tannin contents: Cordia elaeagnoides, Platymiscium lasiocarpum, Vitex mollis, and Haematoxylon brasiletto, on in vitro methane (CH4) production at 24 h post incubation. The analysis was performed using the in vitro gas production technique, with three levels of inclusion/species: 600, 800, and 1,000 mg and with 4 replicates/species/level of inclusion. The substrate was incubated at 39°C, and the gas and CH4 production were recorded at 4, 8, 12, and 24 h post incubation. The data collected was analyzed through Pearson correlation, polinomial regression and fixed effects models. There were negative correlations between FTS-total gas volume (r = −0.40; p<0.001); FTS-volume of CH4 produced (r = −0.40; p<0.001) and between the inclusion level-volume of CH4 produced (r = −0.20; p<0.001). As well as a positive correlation between hours post incubation-total gas volume (r = 0.42; p<0.001) and between hours post incubation-volume of CH4 produced (r = 0.48; p<0.001). The FTS: C. elaeagnoides, V. mollis, and H. brasiletto have potential, in the three inclusion levels analyzed, to reduce CH4 emission on in vitro trials (>32.7%), taking into account the total CH4 production at 24 h of the forage used as reference (Avena sativa). It’s suggested that C. elaeagnoides-according to its crude protein, neutral detergent fiber, and condensed tannins content- is the best alternative within the FTS analyzed, for feeding ruminants and for the control of CH4 emissions during the dry season. PMID:26732330

Condensed tannins: Base-catalysed reactions of polymeric procyanidins with toluene-α-thiol, liability of the interflavanoid bond and pyran ring

Treesearch

Peter E. Laks; Richard W. Hemingway

1987-01-01

Reaction of polymeric procyanidins (condensed tannins) with toluene-α-thiol at pH 12.0 and 23°C gave predominantly one stereoisomer of 1.3-bisbenzylthio-1-(3,4-dihydroxyphenyl)-3-(2,4,6-trihydroxyphenyl) propan-2-ol (10) by stereoselective reaction at C-4 and C-2 of the Quinone methide derived from the upper 2,3-cis procyanidin units....

Spectroscopic and biological activities studies of bivalent transition metal complexes of Schiff bases derived from condensation of 1,4-phenylenediamine and benzopyrone derivatives.

PubMed

Sherif, Omaima E; Abdel-Kader, Nora S

2014-01-03

Many tools of analysis such as elemental analyses, infrared, ultraviolet-visible, electron spin resonance (ESR) and thermal analysis, as well as conductivity and magnetic susceptibility measurements were used to elucidate the structures of the newly prepared Co(II), Ni(II) and Cu(II) complexes with Schiff bases derived from the condensation of 1,4-phenylenediamine with 6-formyl-7-hydroxy-5-methoxy-2-methylbenzo-pyran-4-one (H2L) or 5,7-dihydroxy-6-formyl-2-methylbenzopyran-4-one (H4L). The data showed that all formed complexes are 1:1 or 2:2 (M:L) and non-electrolyte chelates. The Co(II) and Cu(II) complexes of the two Schiff bases were screened for antibacterial activities by the disk diffusion method. The antibacterial activity was screened using Escherichia coli and Staphylococcus capitis but the antifungal activity was examined by using Aspergillus flavus and Candida albicans. The Results showed that the tested complexes have antibacterial, except CuH4L, but not antifungal activities. Copyright © 2013 Elsevier B.V. All rights reserved.

Analytical solutions for coagulation and condensation kinetics of composite particles

NASA Astrophysics Data System (ADS)

Piskunov, Vladimir N.

2013-04-01

The processes of composite particles formation consisting of a mixture of different materials are essential for many practical problems: for analysis of the consequences of accidental releases in atmosphere; for simulation of precipitation formation in clouds; for description of multi-phase processes in chemical reactors and industrial facilities. Computer codes developed for numerical simulation of these processes require optimization of computational methods and verification of numerical programs. Kinetic equations of composite particle formation are given in this work in a concise form (impurity integrated). Coagulation, condensation and external sources associated with nucleation are taken into account. Analytical solutions were obtained in a number of model cases. The general laws for fraction redistribution of impurities were defined. The results can be applied to develop numerical algorithms considerably reducing the simulation effort, as well as to verify the numerical programs for calculation of the formation kinetics of composite particles in the problems of practical importance.

Thermodynamic and economic analysis of heat pumps for energy recovery in industrial processes

NASA Astrophysics Data System (ADS)

Urdaneta-B, A. H.; Schmidt, P. S.

1980-09-01

A computer code has been developed for analyzing the thermodynamic performance, cost and economic return for heat pump applications in industrial heat recovery. Starting with basic defining characteristics of the waste heat stream and the desired heat sink, the algorithm first evaluates the potential for conventional heat recovery with heat exchangers, and if applicable, sizes the exchanger. A heat pump system is then designed to process the residual heating and cooling requirements of the streams. In configuring the heat pump, the program searches a number of parameters, including condenser temperature, evaporator temperature, and condenser and evaporator approaches. All system components are sized for each set of parameters, and economic return is estimated and compared with system economics for conventional processing of the heated and cooled streams (i.e., with process heaters and coolers). Two case studies are evaluated, one in a food processing application and the other in an oil refinery unit.

Performance Analysis of Hybrid ARQ Protocols in a Slotted Code Division Multiple-Access Network

DTIC Science & Technology

1989-08-01

Convolutional Codes . in Proc Int. Conf. Commun., 21.4.1-21.4.5, 1987. [27] J. Hagenauer. Rate Compatible Punctured Convolutional Codes . in Proc Int. Conf...achieved by using a low rate (r = 0.5), high constraint length (e.g., 32) punctured convolutional code . Code puncturing provides for a variable rate code ...investigated the use of convolutional codes in Type II Hybrid ARQ protocols. The error

Formation of H2-He substellar bodies in cold conditions. Gravitational stability of binary mixtures in a phase transition

NASA Astrophysics Data System (ADS)

Füglistaler, A.; Pfenniger, D.

2016-06-01

Context. Molecular clouds typically consist of 3/4 H2, 1/4 He and traces of heavier elements. In an earlier work we showed that at very low temperatures and high densities, H2 can be in a phase transition leading to the formation of ice clumps as large as comets or even planets. However, He has very different chemical properties and no phase transition is expected before H2 in dense interstellar medium conditions. The gravitational stability of fluid mixtures has been studied before, but these studies did not include a phase transition. Aims: We study the gravitational stability of binary fluid mixtures with special emphasis on when one component is in a phase transition. The numerical results are aimed at applications in molecular cloud conditions, but the theoretical results are more general. Methods: First, we study the gravitational stability of van der Waals fluid mixtures using linearized analysis and examine virial equilibrium conditions using the Lennard-Jones intermolecular potential. Then, combining the Lennard-Jones and gravitational potentials, the non-linear dynamics of fluid mixtures are studied via computer simulations using the molecular dynamics code LAMMPS. Results: Along with the classical, ideal-gas Jeans instability criterion, a fluid mixture is always gravitationally unstable if it is in a phase transition because compression does not increase pressure. However, the condensed phase fraction increases. In unstable situations the species can separate: in some conditions He precipitates faster than H2, while in other conditions the converse occurs. Also, for an initial gas phase collapse the geometry is essential. Contrary to spherical or filamentary collapses, sheet-like collapses starting below 15 K easily reach H2 condensation conditions because then they are fastest and both the increase of heating and opacity are limited. Conclusions: Depending on density, temperature and mass, either rocky H2 planetoids, or gaseous He planetoids form. H2 planetoids are favoured by high density, low temperature and low mass, while He planetoids need more mass and can form at temperature well above the critical value.

Effect of condensed tannins on forage nutritive value and greenhouse gas output of an orchardgrass diet

USDA-ARS?s Scientific Manuscript database

Greenhouse gas (GHG) emissions from livestock account for 43%, 29%, and 27% of CH4, N2O and CO2, respectively, of global GHG emissions from livestock. Legumes containing condensed tannins (CT) have been shown to decrease enteric CH4 in ruminants; however, research is lacking on how increased CT leve...

A beam condenser for infrared spectrophotometers.

PubMed

Brandt, R C

1969-02-01

The design and performance of a beam condenser for ir spectrophotometers such as the Beckman model IR-11 is described. The instrument has an image size of 4 mm x 8 mm and permits the use of samples mounted in the tail of a cryostat whose outside dimension is as large as 7 cm square. Applications to negative light flux spectroscopy are described, in particular, the direct measurement of the longitudinal optical frequency of lattice vibration for AgBr and AgCl.

Total synthesis of 4-acetyl-1,3-dihydroimidazo[4,5-c]pyridin-2-one, a new microbial metabolite from a Streptomyces species.

PubMed

Bender, Tobias; von Zezschwitz, Paultheo

2009-07-01

The structure of a new secondary metabolite from Streptomyces sp. was determined as 4-acetyl-1,3-dihydroimidazo[4,5-c]pyridin-2-one by synthesis of the natural product itself and of the regioisomeric 7-acetylimidazo[4,5-b]pyridine derivative. The former compound was prepared, in 28% overall yield, in a sequence of nitration, reduction, condensation, and Stille reaction of 4-aminopyridine, while the regioisomer was obtained in 5% overall yield by amination, nitration, reduction, condensation, and oxidation of 4-ethylpyridine.

Impurity-induced divertor plasma oscillations

DOE PAGES

Smirnov, R. D.; Kukushkin, A. S.; Krasheninnikov, S. I.; ...

2016-01-07

Two different oscillatory plasma regimes induced by seeding the plasma with high- and low-Z impurities are found for ITER-like divertor plasmas, using computer modeling with the DUSTT/UEDGE and SOLPS4.3 plasma-impurity transport codes. The oscillations are characterized by significant variations of the impurity-radiated power and of the peak heat load on the divertor targets. Qualitative analysis of the divertor plasma oscillations reveals different mechanisms driving the oscillations in the cases of high- and low-Z impurity seeding. The oscillations caused by the high-Z impurities are excited near the X-point by an impurity-related instability of the radiation-condensation type, accompanied by parallel impurity ionmore » transport affected by the thermal and plasma friction forces. The driving mechanism of the oscillations induced by the low-Z impurities is related to the cross-field transport of the impurity atoms, causing alteration between the high and low plasma temperature regimes in the plasma recycling region near the divertor targets. As a result, the implications of the impurity-induced plasma oscillations for divertor operation in the next generation tokamaks are also discussed.« less

Galaxies and gas in a cold dark matter universe

NASA Technical Reports Server (NTRS)

Katz, Neal; Hernquist, Lars; Weinberg, David H.

1992-01-01

We use a combined gravity/hydrodynamics code to simulate the formation of structure in a random 22 Mpc cube of a cold dark matter universe. Adiabatic compression and shocks heat much of the gas to temperatures of 10 exp 6 - 10 exp 7 K, but a fraction of the gas cools radiatively to about 10 exp 4 K and condenses into discrete, highly overdense lumps. We identify these lumps with galaxies. The high-mass end of their baryonic mass function fits the form of the observed galaxy luminosity function. They retain independent identities after their dark halos merge, so gravitational clustering produces groups of galaxies embedded in relatively smooth envelopes of hot gas and dark matter. The galaxy correlation function is approximately an r exp -2.1 power law from separations of 35 kpc to 7 Mpc. Galaxy fluctuations are biased relative to dark matter fluctuations by a factor b about 1.5. We find no significant 'velocity bias' between galaxies and dark matter particles. However, virial analysis of the simulation's richest group leads to an estimated Omega of about 0.3, even though the simulation adopts Omega = 1.

Applications of Derandomization Theory in Coding

NASA Astrophysics Data System (ADS)

Cheraghchi, Mahdi

2011-07-01

Randomized techniques play a fundamental role in theoretical computer science and discrete mathematics, in particular for the design of efficient algorithms and construction of combinatorial objects. The basic goal in derandomization theory is to eliminate or reduce the need for randomness in such randomized constructions. In this thesis, we explore some applications of the fundamental notions in derandomization theory to problems outside the core of theoretical computer science, and in particular, certain problems related to coding theory. First, we consider the wiretap channel problem which involves a communication system in which an intruder can eavesdrop a limited portion of the transmissions, and construct efficient and information-theoretically optimal communication protocols for this model. Then we consider the combinatorial group testing problem. In this classical problem, one aims to determine a set of defective items within a large population by asking a number of queries, where each query reveals whether a defective item is present within a specified group of items. We use randomness condensers to explicitly construct optimal, or nearly optimal, group testing schemes for a setting where the query outcomes can be highly unreliable, as well as the threshold model where a query returns positive if the number of defectives pass a certain threshold. Finally, we design ensembles of error-correcting codes that achieve the information-theoretic capacity of a large class of communication channels, and then use the obtained ensembles for construction of explicit capacity achieving codes. [This is a shortened version of the actual abstract in the thesis.

Oligodeoxynucleotide nanostructure formation in the presence of polypropyleneimine dendrimers and their uptake in breast cancer cells

NASA Astrophysics Data System (ADS)

Chen, Alex M.; Santhakumaran, Latha M.; Nair, Sandhya K.; Amenta, Peter S.; Thomas, Thresia; He, Huixin; Thomas, T. J.

2006-11-01

We studied the efficacy of five generations of polypropyleneimine (PPI) dendrimer to provoke nanostructure formation from a 21-nucleotide antisense oligodeoxynucleotide (ODN). Nanostructure formation was observed with all generations of dendrimer by light scattering and microscopic techniques. The efficacy of the dendrimers increased with generation number. Atomic force microscopy (AFM) was used to study the morphology of the structures at different condensation stages. Based on the observed nanostructures, we propose a zipping condensation mechanism, which is very different from the condensation pathways of high molecular weight DNA polymers. Electron microscopy showed the presence of toroidal nanoparticles. Confocal microscopic analysis showed that the nanostructures formed with G-4 and G-5 dendrimers could undergo facile cellular uptake in a breast cancer cell line, MDA-MB-231, whereas nanostructures formed with G-1 to G-3 dendrimers lacked this ability. Nanoparticles formed with G-1 to G-3 dendrimers showed significantly lower zeta potential (5.2-6.5 mV) than those (12-18 mV) of particles formed with G-4 and G-5 dendrimers. These results show that the structure and charge density of the dendrimers are important in ODN nanoparticle formation and cellular transport and that G-4 and G-5 dendrimers are useful in cellular delivery of antisense ODN.

An evaluation of .06 tapered gutta-percha cones for filling of .06 taper prepared curved root canals.

PubMed

Gordon, M P J; Love, R M; Chandler, N P

2005-02-01

To compare the area occupied by gutta-percha, sealer, or void in standardized .06 tapered prepared simulated curved canals and in mesio-buccal canals of extracted maxillary first molars filled with a single .06 gutta-percha point and sealer or lateral condensation of multiple .02 gutta-percha points and sealer. Simulated canals in resin blocks with either a 30 degrees curve and radius of 10.5 mm (n = 20) or a 58 degrees curve and 4.7 mm radius (n = 20) and curved mesio-buccal canals of extracted maxillary first molars (n = 20) were prepared using .06 ProFiles in a variable tip crown-down sequence to an apical size 35 at 0.5 mm from the canal terminus or apical foramen. Ten 30 degrees and 58 degrees curved resin canals and 10 canals in the extracted teeth group were obturated with .02 taper gutta-percha cones and AH 26 sealer using lateral condensation. The time required to obturate was recorded. The remaining canals were obturated with a single .06 taper gutta-percha cone and AH 26 sealer. Excess gutta-percha was removed from the specimens using heat and the warm mass vertically condensed. Horizontal sections were cut at 0.5, 1.5, 2.5, 4.5, 7.5 and 11.5 mm from the canal terminus or apical foramen. Colour photographs were taken using an Olympus 35 mm camera attached to a stereomicroscope set at x40 magnification, and then digitized using a flatbed scanner. The cross-sectional area of the canal contents was analysed using Adobe PhotoShop. The percentage of gutta-percha, sealer or voids to the total root canal area were derived and data analysed using unpaired Student's t-test and the Mann-Whitney U-test. In the 30 degrees curved canals the levels had between 94 and 100% of the area filled with gutta-percha with no significant difference (P > 0.05) between the lateral condensation and single cone techniques. In the 58 degrees curved canals the levels had 92-99% of the area filled with gutta-percha, with the single cone technique having significantly (P < 0.05) more gutta-percha fill at the 2.5 mm level only. In the mesio-buccal canals of the teeth the levels had between 72 and 96% of the area filled with gutta-percha with no significant difference (P > 0.05) between the lateral condensation and single cone technique. The time for obturation was significantly (P < 0.05) greater for lateral condensation compared with the single cone technique in all groups. The .06 taper single cone technique was comparable with lateral condensation in the amount of gutta-percha occupying a prepared .06 tapered canal. The .06 single cone technique was faster than lateral condensation.

Cloud Atlas: Rotational Modulations in the L/T Transition Brown Dwarf Companion HN Peg B

NASA Astrophysics Data System (ADS)

Zhou, Yifan; Apai, Dániel; Metchev, Stanimir; Lew, Ben W. P.; Schneider, Glenn; Marley, Mark S.; Karalidi, Theodora; Manjavacas, Elena; Bedin, Luigi R.; Cowan, Nicolas B.; Miles-Páez, Paulo A.; Lowrance, Patrick J.; Radigan, Jacqueline; Burgasser, Adam J.

2018-03-01

Time-resolved observations of brown dwarfs’ rotational modulations provide powerful insights into the properties of condensate clouds in ultra-cool atmospheres. Multi-wavelength light curves reveal cloud vertical structures, condensate particle sizes, and cloud morphology, which directly constrain condensate cloud and atmospheric circulation models. We report results from Hubble Space Telescope/Wide Field Camera 3 near-infrared G141 taken in six consecutive orbits observations of HN Peg B, an L/T transition brown dwarf companion to a G0V type star. The best-fit sine wave to the 1.1–1.7 μm broadband light curve has an amplitude of 1.206% ± 0.025% and period of 15.4 ± 0.5 hr. The modulation amplitude has no detectable wavelength dependence except in the 1.4 μm water absorption band, indicating that the characteristic condensate particle sizes are large (>1 μm). We detect significantly (4.4σ) lower modulation amplitude in the 1.4 μm water absorption band and find that HN Peg B’s spectral modulation resembles those of early T type brown dwarfs. We also describe a new empirical interpolation method to remove spectral contamination from the bright host star. This method may be applied in other high-contrast time-resolved observations with WFC3.

Evidence for a pore-filling mechanism in the adsorption of aromatic hydrocarbons to a natural wood char.

PubMed

Nguyen, Thanh H; Cho, Hyun-Hee; Poster, Dianne L; Ball, William P

2007-02-15

Sorption isotherms for five aromatic hydrocarbons were obtained with a natural wood char (NC1) and its residue after solvent extraction (ENC1). Substantial isotherm nonlinearity was observed in all cases. ENC1 showed higher BET surface area, higher nitrogen-accessible micropore volume, and lower mass of extractable organic chemicals, including quantifiable polycyclic aromatic hydrocarbons (PAHs),while the two chars showed identical surface oxygen/ carbon (O/C) ratio. For two chlorinated benzenes that normally condense as liquids at the temperatures used, sorption isotherms with NC1 and ENC1 were found to be statistically identical. For the solid-phase compounds (1,4-dichlorobenzene (1,4-DCB) and two PAHs), sorption was statistically higher with ENC1, thus demonstrating sorption effects due to both (1) authigenic organic content in the sorbentand (2)the sorbate's condensed state. Polanyi-based isotherm modeling, pore size measurements, and comparisons with activated carbon showthe relative importance of adsorptive pore filling and help explain results. With both chars, maximum sorption increased in the order of decreasing molecular diameter: phenanthrene < naphthalene < 1,2-dichlorobenzene/1,2,4-trichlorobenzene < 1,4-DCB. Comparison of 1,4- and 1,2-DCB shows that the critical molecular diameter was apparently more important than the condensed state, suggesting that 1,4-DCB sorbed in the liquid state for ENC1.

Influence of organic films on the evaporation and condensation of water in aerosol

PubMed Central

Davies, James F.; Miles, Rachael E. H.; Haddrell, Allen E.; Reid, Jonathan P.

2013-01-01

Uncertainties in quantifying the kinetics of evaporation and condensation of water from atmospheric aerosol are a significant contributor to the uncertainty in predicting cloud droplet number and the indirect effect of aerosols on climate. The influence of aerosol particle surface composition, particularly the impact of surface active organic films, on the condensation and evaporation coefficients remains ambiguous. Here, we report measurements of the influence of organic films on the evaporation and condensation of water from aerosol particles. Significant reductions in the evaporation coefficient are shown to result when condensed films are formed by monolayers of long-chain alcohols [CnH(2n+1)OH], with the value decreasing from 2.4 × 10−3 to 1.7 × 10−5 as n increases from 12 to 17. Temperature-dependent measurements confirm that a condensed film of long-range order must be formed to suppress the evaporation coefficient below 0.05. The condensation of water on a droplet coated in a condensed film is shown to be fast, with strong coherence of the long-chain alcohol molecules leading to islanding as the water droplet grows, opening up broad areas of uncoated surface on which water can condense rapidly. We conclude that multicomponent composition of organic films on the surface of atmospheric aerosol particles is likely to preclude the formation of condensed films and that the kinetics of water condensation during the activation of aerosol to form cloud droplets is likely to remain rapid. PMID:23674675

Influence of organic films on the evaporation and condensation of water in aerosol.

PubMed

Davies, James F; Miles, Rachael E H; Haddrell, Allen E; Reid, Jonathan P

2013-05-28

Uncertainties in quantifying the kinetics of evaporation and condensation of water from atmospheric aerosol are a significant contributor to the uncertainty in predicting cloud droplet number and the indirect effect of aerosols on climate. The influence of aerosol particle surface composition, particularly the impact of surface active organic films, on the condensation and evaporation coefficients remains ambiguous. Here, we report measurements of the influence of organic films on the evaporation and condensation of water from aerosol particles. Significant reductions in the evaporation coefficient are shown to result when condensed films are formed by monolayers of long-chain alcohols [C(n)H(2n+1)OH], with the value decreasing from 2.4 × 10(-3) to 1.7 × 10(-5) as n increases from 12 to 17. Temperature-dependent measurements confirm that a condensed film of long-range order must be formed to suppress the evaporation coefficient below 0.05. The condensation of water on a droplet coated in a condensed film is shown to be fast, with strong coherence of the long-chain alcohol molecules leading to islanding as the water droplet grows, opening up broad areas of uncoated surface on which water can condense rapidly. We conclude that multicomponent composition of organic films on the surface of atmospheric aerosol particles is likely to preclude the formation of condensed films and that the kinetics of water condensation during the activation of aerosol to form cloud droplets is likely to remain rapid.

3D MHD Modeling of Prominence Formation by Plasma Evaporation and Condensation

NASA Astrophysics Data System (ADS)

Torok, T.; Lionello, R.; Mikic, Z.; Downs, C.; Titov, V. S.

2017-12-01

The formation of prominence material in the solar corona still belongs to the open questions of solar physics. There exists a consensus that prominence plasma has to be of chromospheric origin, but the mechanisms by which it accumulates in the corona are still not well understood. The presently most accepted scenario invokes the evaporation of chromospheric plasma via foot point heating and its subsequent condensation in the corona via thermal instabilities. This scenario has been successfully modeled in 1D hydrodynamic simulations along single field lines of a static magnetic field, but a more appropriate, fully 3D treatment of the thermodynamics in time-dependent magnetic fields was started just very recently by Xia et al. Our group at PSI has recently begun to engage in this challenging task as well, using our time-dependent, fully 3D thermodynamic MHD code MAS. For our investigation we consider two different coronal flux-rope configurations, using the analytical model by Titov and Démoulin and a model in which an elongated flux rope is constructed by photospheric flows. We investigate the plasma behavior for both configurations, using heating models of different complexity, and accompany our analysis by 1D loop simulations performed along selected field lines. In this presentation, we outline our modeling approach and discuss the results obtained so far.

Code manual for CONTAIN 2.0: A computer code for nuclear reactor containment analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murata, K.K.; Williams, D.C.; Griffith, R.O.

1997-12-01

The CONTAIN 2.0 computer code is an integrated analysis tool used for predicting the physical conditions, chemical compositions, and distributions of radiological materials inside a containment building following the release of material from the primary system in a light-water reactor accident. It can also predict the source term to the environment. CONTAIN 2.0 is intended to replace the earlier CONTAIN 1.12, which was released in 1991. The purpose of this Code Manual is to provide full documentation of the features and models in CONTAIN 2.0. Besides complete descriptions of the models, this Code Manual provides a complete description of themore » input and output from the code. CONTAIN 2.0 is a highly flexible and modular code that can run problems that are either quite simple or highly complex. An important aspect of CONTAIN is that the interactions among thermal-hydraulic phenomena, aerosol behavior, and fission product behavior are taken into account. The code includes atmospheric models for steam/air thermodynamics, intercell flows, condensation/evaporation on structures and aerosols, aerosol behavior, and gas combustion. It also includes models for reactor cavity phenomena such as core-concrete interactions and coolant pool boiling. Heat conduction in structures, fission product decay and transport, radioactive decay heating, and the thermal-hydraulic and fission product decontamination effects of engineered safety features are also modeled. To the extent possible, the best available models for severe accident phenomena have been incorporated into CONTAIN, but it is intrinsic to the nature of accident analysis that significant uncertainty exists regarding numerous phenomena. In those cases, sensitivity studies can be performed with CONTAIN by means of user-specified input parameters. Thus, the code can be viewed as a tool designed to assist the knowledge reactor safety analyst in evaluating the consequences of specific modeling assumptions.« less

Hydrodynamic modeling of petroleum reservoirs using simulator MUFITS

NASA Astrophysics Data System (ADS)

Afanasyev, Andrey

2015-04-01

MUFITS is new noncommercial software for numerical modeling of subsurface processes in various applications (www.mufits.imec.msu.ru). To this point, the simulator was used for modeling nonisothermal flows in geothermal reservoirs and for modeling underground carbon dioxide storage. In this work, we present recent extension of the code to petroleum reservoirs. The simulator can be applied in conventional black oil modeling, but it also utilizes a more complicated models for volatile oil and gas condensate reservoirs as well as for oil rim fields. We give a brief overview of the code by providing the description of internal representation of reservoir models, which are constructed of grid blocks, interfaces, stock tanks as well as of pipe segments and pipe junctions for modeling wells and surface networks. For conventional black oil approach, we present the simulation results for SPE comparative tests. We propose an accelerated compositional modeling method for sub- and supercritical flows subjected to various phase equilibria, particularly to three-phase equilibria of vapour-liquid-liquid type. The method is based on the calculation of the thermodynamic potential of reservoir fluid as a function of pressure, total enthalpy and total composition and storing its values as a spline table, which is used in hydrodynamic simulation for accelerated PVT properties prediction. We provide the description of both the spline calculation procedure and the flashing algorithm. We evaluate the thermodynamic potential for a mixture of two pseudo-components modeling the heavy and light hydrocarbon fractions. We develop a technique for converting black oil PVT tables to the potential, which can be used for in-situ hydrocarbons multiphase equilibria prediction under sub- and supercritical conditions, particularly, in gas condensate and volatile oil reservoirs. We simulate recovery from a reservoir subject to near-critical initial conditions for hydrocarbon mixture. We acknowledge financial support by a Grant from the president of the Russian Federation (SP-2222.2012.5) and by Russian foundation for basic research (RFBR 15-31-20585).

SU-E-T-212: Comparison of TG-43 Dosimetric Parameters of Low and High Energy Brachytherapy Sources Obtained by MCNP Code Versions of 4C, X and 5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zehtabian, M; Zaker, N; Sina, S

2015-06-15

Purpose: Different versions of MCNP code are widely used for dosimetry purposes. The purpose of this study is to compare different versions of the MCNP codes in dosimetric evaluation of different brachytherapy sources. Methods: The TG-43 parameters such as dose rate constant, radial dose function, and anisotropy function of different brachytherapy sources, i.e. Pd-103, I-125, Ir-192, and Cs-137 were calculated in water phantom. The results obtained by three versions of Monte Carlo codes (MCNP4C, MCNPX, MCNP5) were compared for low and high energy brachytherapy sources. Then the cross section library of MCNP4C code was changed to ENDF/B-VI release 8 whichmore » is used in MCNP5 and MCNPX codes. Finally, the TG-43 parameters obtained using the MCNP4C-revised code, were compared with other codes. Results: The results of these investigations indicate that for high energy sources, the differences in TG-43 parameters between the codes are less than 1% for Ir-192 and less than 0.5% for Cs-137. However for low energy sources like I-125 and Pd-103, large discrepancies are observed in the g(r) values obtained by MCNP4C and the two other codes. The differences between g(r) values calculated using MCNP4C and MCNP5 at the distance of 6cm were found to be about 17% and 28% for I-125 and Pd-103 respectively. The results obtained with MCNP4C-revised and MCNPX were similar. However, the maximum difference between the results obtained with the MCNP5 and MCNP4C-revised codes was 2% at 6cm. Conclusion: The results indicate that using MCNP4C code for dosimetry of low energy brachytherapy sources can cause large errors in the results. Therefore it is recommended not to use this code for low energy sources, unless its cross section library is changed. Since the results obtained with MCNP4C-revised and MCNPX were similar, it is concluded that the difference between MCNP4C and MCNPX is their cross section libraries.« less

Molten salt corrosion of SiC and Si3N4

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.; Smialek, James L.; Fox, Dennis S.

1988-01-01

Industrial systems such as heat engines and heat exchangers involve harsh environments. The structural materials are subjected to high temperatures as well as corrosive gases and condensed phases. Past experience with metal alloys has shown that these condensed phases can be particularly corrosive and are often the limiting factor in the operation of these systems. In a heat engine the most common condensed corrodent is Na2SO4 whereas in a heat exchanger an oxide slag may be present. The primary emphasis is on Na2SO4 induced corrosion, however, similarities and differences to oxide slag are also discussed. The extensive research on corrosion of metal alloys has led to understanding and controlling corrosion for these materials. Currently silicon based ceramics are prime candidates for the applications discussed. Therefore it is important to understand the effects of condensed phase deposits on this emerging class of high temperature materials. Both the thermodynamic and strength of the ceramic is also examined. Finally some control strategies for corrosion of silicon based ceramics are explored.

Hyperbolic and semi-hyperbolic surface codes for quantum storage

NASA Astrophysics Data System (ADS)

Breuckmann, Nikolas P.; Vuillot, Christophe; Campbell, Earl; Krishna, Anirudh; Terhal, Barbara M.

2017-09-01

We show how a hyperbolic surface code could be used for overhead-efficient quantum storage. We give numerical evidence for a noise threshold of 1.3 % for the \\{4,5\\}-hyperbolic surface code in a phenomenological noise model (as compared with 2.9 % for the toric code). In this code family, parity checks are of weight 4 and 5, while each qubit participates in four different parity checks. We introduce a family of semi-hyperbolic codes that interpolate between the toric code and the \\{4,5\\}-hyperbolic surface code in terms of encoding rate and threshold. We show how these hyperbolic codes outperform the toric code in terms of qubit overhead for a target logical error probability. We show how Dehn twists and lattice code surgery can be used to read and write individual qubits to this quantum storage medium.

Theory of supercompression of vapor bubbles and nanoscale thermonuclear fusion

NASA Astrophysics Data System (ADS)

Nigmatulin, Robert I.; Akhatov, Iskander Sh.; Topolnikov, Andrey S.; Bolotnova, Raisa Kh.; Vakhitova, Nailya K.; Lahey, Richard T.; Taleyarkhan, Rusi P.

2005-10-01

This paper provides the theoretical basis for energetic vapor bubble implosions induced by a standing acoustic wave. Its primary goal is to describe, explain, and demonstrate the plausibility of the experimental observations by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] of thermonuclear fusion for imploding cavitation bubbles in chilled deuterated acetone. A detailed description and analysis of these data, including a resolution of the criticisms that have been raised, together with some preliminary HYDRO code simulations, has been given by Nigmatulin et al. [Vestnik ANRB (Ufa, Russia) 4, 3 (2002); J. Power Energy 218-A, 345 (2004)] and Lahey et al. [Adv. Heat Transfer (to be published)]. In this paper a hydrodynamic shock (i.e., HYDRO) code model of the spherically symmetric motion for a vapor bubble in an acoustically forced liquid is presented. This model describes cavitation bubble cluster growth during the expansion period, followed by a violent implosion during the compression period of the acoustic cycle. There are two stages of the bubble dynamics process. The first, low Mach number stage, comprises almost all the time of the acoustic cycle. During this stage, the radial velocities are much less than the sound speeds in the vapor and liquid, the vapor pressure is very close to uniform, and the liquid is practically incompressible. This process is characterized by the inertia of the liquid, heat conduction, and the evaporation or condensation of the vapor. The second, very short, high Mach number stage is when the radial velocities are the same order, or higher, than the sound speeds in the vapor and liquid. In this stage high temperatures, pressures, and densities of the vapor and liquid take place. The model presented herein has realistic equations of state for the compressible liquid and vapor phases, and accounts for nonequilibrium evaporation/condensation kinetics at the liquid/vapor interface. There are interacting shock waves in both phases, which converge toward and reflect from the center of the bubble, causing dissociation, ionization, and other related plasma physics phenomena during the final stage of bubble collapse. For a vapor bubble in a deuterated organic liquid (e.g., acetone), during the final stage of collapse there is a nanoscale region (diameter ˜100nm) near the center of the bubble in which, for a fraction of a picosecond, the temperatures and densities are extremely high (˜108K and ˜10g/cm3, respectively) such that thermonuclear fusion may take place. To quantify this, the kinetics of the local deuterium/deuterium (D/D) nuclear fusion reactions was used in the HYDRO code to determine the intensity of the fusion reactions. Numerical HYDRO code simulations of the bubble implosion process have been carried out for the experimental conditions used by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] at Oak Ridge National Laboratory. The results show good agreement with the experimental data on bubble fusion that was measured in chilled deuterated acetone.

Contamination Effects on EUV Optics

NASA Technical Reports Server (NTRS)

Tveekrem, J.

1999-01-01

During ground-based assembly and upon exposure to the space environment, optical surfaces accumulate both particles and molecular condensibles, inevitably resulting in degradation of optical instrument performance. Currently, this performance degradation (and the resulting end-of-life instrument performance) cannot be predicted with sufficient accuracy using existing software tools. Optical design codes exist to calculate instrument performance, but these codes generally assume uncontaminated optical surfaces. Contamination models exist which predict approximate end-of-life contamination levels, but the optical effects of these contamination levels can not be quantified without detailed information about the optical constants and scattering properties of the contaminant. The problem is particularly pronounced in the extreme ultraviolet (EUV, 300-1,200 A) and far (FUV, 1,200-2,000 A) regimes due to a lack of data and a lack of knowledge of the detailed physical and chemical processes involved. Yet it is in precisely these wavelength regimes that accurate predictions are most important, because EUV/FUV instruments are extremely sensitive to contamination.

Ignition and combustion characteristics of metallized propellants, phase 2

NASA Technical Reports Server (NTRS)

Mueller, D. C.; Turns, S. R.

1994-01-01

Experimental and analytical investigations focusing on aluminum/hydrocarbon gel droplet secondary atomization and its effects on gel-fueled rocket engine performance are being conducted. A single laser sheet sizing/velocimetry diagnostic technique, which should eliminate sizing bias in the data collection process, has been designed and constructed to overcome limitations of the two-color forward-scatter technique used in previous work. Calibration of this system is in progress and the data acquisition/validation code is being written. Narrow-band measurements of radiant emission, discussed in previous reports, will be used to determine if aluminum ignition has occurred in a gel droplet. A one-dimensional model of a gel-fueled rocket combustion chamber, described in earlier reports, has been exercised in conjunction with a two-dimensional, two-phase nozzle code to predict the performance of an aluminum/hydrocarbon fueled engine. Estimated secondary atomization effects on propellant burnout distance, condensed particle radiation losses to the chamber walls, and nozzle two phase flow losses are also investigated. Calculations indicate that only modest secondary atomization is required to significantly reduce propellant burnout distances, aluminum oxide residual size, and radiation heat losses. Radiation losses equal to approximately 2-13 percent of the energy released during combustion were estimated, depending on secondary atomization intensity. A two-dimensional, two-phase nozzle code was employed to estimate radiation and nozzle two phase flow effects on overall engine performance. Radiation losses yielded a one percent decrease in engine Isp. Results also indicate that secondary atomization may have less effect on two-phase losses than it does on propellant burnout distance and no effect if oxide particle coagulation and shear induced droplet breakup govern oxide particle size. Engine Isp was found to decrease from 337.4 to 293.7 seconds as gel aluminum mass loading was varied from 0-70 wt percent. Engine Isp efficiencies, accounting for radiation and two phase flow effects, on the order of 0.946 were calculated for a 60 wt percent gel, assuming a fragmentation ratio of five.

38 CFR 4.27 - Use of diagnostic code numbers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Use of diagnostic code... FOR RATING DISABILITIES General Policy in Rating § 4.27 Use of diagnostic code numbers. The diagnostic... residual condition is encountered, requiring rating by analogy, the diagnostic code number will be “built...

38 CFR 4.27 - Use of diagnostic code numbers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Use of diagnostic code... FOR RATING DISABILITIES General Policy in Rating § 4.27 Use of diagnostic code numbers. The diagnostic... residual condition is encountered, requiring rating by analogy, the diagnostic code number will be “built...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbasifar, Reza; Griffiths, Mansel W.; Sabour, Parviz M.

Cronobacter sakazakii is a Gram-negative pathogen found in milk-based formulae that causes infant meningitis. Bacteriophages have been proposed to control bacterial pathogens; however, comprehensive knowledge about a phage is required to ensure its safety before clinical application. We have characterized C. sakazakii phage vB{sub C}saM{sub G}AP32 (GAP32), which possesses the second largest sequenced phage genome (358,663 bp). A total of 571 genes including 545 protein coding sequences and 26 tRNAs were identified, thus more genes than in the smallest bacterium, Mycoplasma genitalium G37. BLASTP and HHpred searches, together with proteomic analyses reveal that only 23.9% of the putative proteins havemore » defined functions. Some of the unique features of this phage include: a chromosome condensation protein, two copies of the large subunit terminase, a predicted signal-arrest-release lysin; and an RpoD-like protein, which is possibly involved in the switch from immediate early to delayed early transcription. Its closest relatives are all extremely large myoviruses, namely coliphage PBECO4 and Klebsiella phage vB{sub K}leM-RaK2, with whom it shares approximately 44% homologous proteins. Since the homologs are not evenly distributed, we propose that these three phages belong to a new subfamily. - Highlights: • Cronobacter sakazakii phage vB{sub C}saM{sub G}AP32 has a genome of 358,663 bp. • It encodes 545 proteins which is more than Mycoplasma genitalium G37. • It is a member of the Myoviridae. • It is peripherally related to coliphage PBECO4 and Klebsiella phage vB{sub K}leM-RaK2. • GAP32 encodes a chromosome condensation protein.« less

Four year-olds use norm-based coding for face identity.

PubMed

Jeffery, Linda; Read, Ainsley; Rhodes, Gillian

2013-05-01

Norm-based coding, in which faces are coded as deviations from an average face, is an efficient way of coding visual patterns that share a common structure and must be distinguished by subtle variations that define individuals. Adults and school-aged children use norm-based coding for face identity but it is not yet known if pre-school aged children also use norm-based coding. We reasoned that the transition to school could be critical in developing a norm-based system because school places new demands on children's face identification skills and substantially increases experience with faces. Consistent with this view, face identification performance improves steeply between ages 4 and 7. We used face identity aftereffects to test whether norm-based coding emerges between these ages. We found that 4 year-old children, like adults, showed larger face identity aftereffects for adaptors far from the average than for adaptors closer to the average, consistent with use of norm-based coding. We conclude that experience prior to age 4 is sufficient to develop a norm-based face-space and that failure to use norm-based coding cannot explain 4 year-old children's poor face identification skills. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis and antiinflammatory activity of some 2-arylamino-2-thiazoline-4-ones.

PubMed

Lesyk, Roman; Zimenkovsky, Boris; Subtelna, Ivanna; Nektegayev, Igor; Kazmirchuk, Gennadij

2003-01-01

A mild and efficent method of synthesis of 2-arylamino-2-thiazoline-4-ones was established using 2-carboethoxymethylthio-2-thiazolin-4-one (II) as a key intermediate. Reaction of 2-carboethoxymethylthio-2-thiazolin-4-one with m- or p-aminophenole afforded 2-(3-or4-oxyphenylamino)-2-thiazoline-4-ones (V, XV). Condensation of V, XV with aromatic aldehydes, according to the Knoevenagel, gives respective 5-arylidene derivatives V-XIII, XVI-XXIX, which were obtained alternatively using m- or p-oxyarylthioureas. 5-Carboxymethylderivatives XIV, XXX were synthesized by condensation of arylthioureas and maleic anhydride in acetic acid. Quantum-chemical calculations were made to confirm the possibility of dynamic amino-imino tautomerism of synthesized compounds. Structure and tautomerism of the obtained substances were confirmed by UV, IR, MS and NMR spectra. Biological activity prediction using the computer program PASS C&T has been made. According to these prediction results, some compounds were tested in vivio for their antiinflammatory activity. 5-[2-Chloro-3-(4-nitrophenyl)-2-propenilidene]-2-(3-hydroxyanilino-2-thiazoline-4-one (XII) possess significant antiinflammatory effect in comparison with diclofenac sodium, aspirin, acetaminofen and phenylbutazone.

Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

NASA Astrophysics Data System (ADS)

Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

2018-06-01

Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

NASA Astrophysics Data System (ADS)

Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

2017-12-01

Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

Theoretical investigation of excitonic magnetism in LaSrCoO4

NASA Astrophysics Data System (ADS)

Fernández Afonso, J.; Sotnikov, A.; Kuneš, J.

2018-04-01

We use the LDA+U approach to search for possible ordered ground states of LaSrCoO4. We find a staggered arrangement of magnetic multipoles to be stable over a broad range of Co 3d interaction parameters. This ordered state can be described as a spin-density-wave-type condensate of dxy \\otimes dx^2-y^2 excitons carrying spin S  =  1. Further, we construct an effective strong-coupling model, calculate the exciton dispersion and investigate closing of the exciton gap, which marks the exciton condensation instability. Comparing the layered LaSrCoO4 with its pseudo cubic analog LaCoO3, we find that for the same interaction parameters the excitonic gap is smaller (possibly vanishing) in the layered cobaltite.

Nucleation time of nanoscale water bridges.

PubMed

Szoszkiewicz, Robert; Riedo, Elisa

2005-09-23

Water capillaries bind together grains of sand. They also can bind an atomic force microscope tip to a substrate. The kinetics of capillary condensation at the nanoscale is studied here using friction force microscopy. At 40% relative humidity we find that the meniscus nucleation times increase from 0.7 to 4.2 ms when the temperature decreases from 332 to 299 K. The nucleation times grow exponentially with the inverse temperature 1/T obeying an Arrhenius law. We obtain a nucleation energy barrier of 7.8 x 10(-20) J and an attempt frequency ranging between 4 and 250 GHz, in excellent agreement with theoretical predictions. These results provide direct experimental evidence that capillary condensation is a thermally activated phenomenon.

CFD Analysis of Evaporation-Condensation Phenomenon In an Evaporation Chamber of Natural Vacuum Solar Desalination

NASA Astrophysics Data System (ADS)

Ambarita, H.; Ronowikarto, A. D.; Siregar, R. E. T.; Setyawan, E. Y.

2018-01-01

Desalination technologies is one of solutions for water scarcity. With using renewable energy, like solar energy, wind energy, and geothermal energy, expected will reduce the energy demand. This required study on the modeling and transport parameters determination of natural vacuum solar desalination by using computational fluid dynamics (CFD) method to simulate the model. A three-dimensional case, two-phase model was developed for evaporation-condensation phenomenon in natural vacuum solar desalination. The CFD simulation results were compared with the avalaible experimental data. The simulation results shows inthat there is a phenomenon of evaporation-condensation in an evaporation chamber. From the simulation, the fresh water productivity is 2.21 litre, and from the experimental is 2.1 litre. This study shows there’s an error of magnitude 0.4%. The CFD results also show that, vacuum pressure will degrade the saturation temperature of sea water.

The time dependent growth of H2O-H2SO4 aerosols by heteromolecular condensation

NASA Technical Reports Server (NTRS)

Hamill, P.

1975-01-01

A theory for the time-dependent growth of solution droplets by heteromolecular condensation is presented. The theory is applied to the growth of H2O-H2SO4 aerosols for relative humidities less than 100 per cent. Growth curves (droplet radius as a function of time) for different values of relative humidity are evaluated.

Adsorption and condensation of amino acids and nucleotides with soluble mineral salts

NASA Technical Reports Server (NTRS)

Orenberg, J.; Lahav, N.

1986-01-01

The directed synthesis of biopolymers in an abiotic environment is presumably a cyclic sequence of steps which may be realized in a fluctuating environment such as a prebiotic pond undergoing wetting-drying cycles. Soluble mineral salts have been proposed as an essential component of this fluctuating environment. The following sequence may be considered as a most primitive mechanism of information transfer in a fluctuating environment: (1) adsorption of a biomolecule onto a soluable mineral salt surface to act as an adsorbed template; (2) specific adsorption of biomonomers onto the adsorbed template; (3) condensation of the adsorbed biomonomers; and (4) desorption of the elongated oligomer. In this investigation, the salts selected for study were CaSO4.2H2O(gypsum), SrSO4, and several other metal sulfates and chlorides. Adsorption of the monomeric species, gly, 5'AMP 5'GMP, and 5'CMP was investigated. The adsorbed template biopolymers used were Poly-A, Poly-G, Poly-C, and Poly-U. The results of studies involving these experimental participants, the first two steps of the proposed primitive information transfer mechanism, and condensation of amino acids to form oligomers in a fluctuating environment are to be reported.

On the design of turbo codes

NASA Technical Reports Server (NTRS)

Divsalar, D.; Pollara, F.

1995-01-01

In this article, we design new turbo codes that can achieve near-Shannon-limit performance. The design criterion for random interleavers is based on maximizing the effective free distance of the turbo code, i.e., the minimum output weight of codewords due to weight-2 input sequences. An upper bound on the effective free distance of a turbo code is derived. This upper bound can be achieved if the feedback connection of convolutional codes uses primitive polynomials. We review multiple turbo codes (parallel concatenation of q convolutional codes), which increase the so-called 'interleaving gain' as q and the interleaver size increase, and a suitable decoder structure derived from an approximation to the maximum a posteriori probability decision rule. We develop new rate 1/3, 2/3, 3/4, and 4/5 constituent codes to be used in the turbo encoder structure. These codes, for from 2 to 32 states, are designed by using primitive polynomials. The resulting turbo codes have rates b/n (b = 1, 2, 3, 4 and n = 2, 3, 4, 5, 6), and include random interleavers for better asymptotic performance. These codes are suitable for deep-space communications with low throughput and for near-Earth communications where high throughput is desirable. The performance of these codes is within 1 dB of the Shannon limit at a bit-error rate of 10(exp -6) for throughputs from 1/15 up to 4 bits/s/Hz.

Physical model of a fumarolic system inferred from a high-resolution 3-D Resistivity image of Solfatara volcano

NASA Astrophysics Data System (ADS)

Gresse, Marceau; Vandemeulebrouck, Jean; Byrdina, Svetlana; Chiodini, Giovanni; Rinaldi, Antonio Pio; Johnson, Timothy C.; Ricci, Tullio; Petrillo, Zaccaria; Vilardo, Giuseppe; Lebourg, Thomas; Mangiacapra, Annarita

2017-04-01

Solfatara crater, located inside the Phlegrean Fields caldera, is showing a significant unrest activity since 10 years with a increase of ground deformation, degassing and heating. Electrical Resistivity Imaging was performed between 2012 and 2016 with the purpose of improving our knowledge of the shallow hydrothermal system. The complete dataset includes 43,432 D-C measurements inverted using the E4D code. This 3-D inversion was compared with the mappings of surface temperature, diffuse soil CO2 flux and self-potential in order to better constrain the interpretation of the observed resistivity structure in terms of lithological contrasts and hydrothermal signatures. For the first time, we highlighted in 3-D the main geological units: Monte Olibano lava dome and Solfatara crypto-dome appear as two relatively resistive bodies (50-100 Ω.m). Furthermore, the resistivity model clearly revealed the contrasting geometry of the hydrothermal circulation in the Solfatara crater. A channel-like conductive structure (7 Ω.m) represents the condensate that flows from the main fumarolic area down to the liquid-dominated Fangaia mud pool. This interpretation is consistent with the negative Self-Potential anomaly and with the surface observations. We imaged at a metric-resolution the two main fumaroles, Bocca Grande and Bocca Nuova, that have the following geochemical characteristics. Bocca Grande vent: 162°C, ˜150 t of CO2 released per day with a mass ratio CO2/H20 = 0.4 and Bocca Nuova vent: 148°C, ˜50 t of CO2 released per day with a mass ratio CO2/H20 = 0.45. The differences between these geochemical characteristics could lead one to believe that they are fed by two distinct sources at depth. On the contrary, our resistivity model shows that the two fumarolic vents are directly connected to a common resistive body (30-50 Ω.m) at a depth of 50 meters. This structure likely represents a single gas reservoir feeding the two fumaroles. Its depth corresponds indeed to a steam source at a pressure of 6 bar and at a temperature of least 165 °C. The geophysical images combined with the geochemical data allowed us to build up a multiphase fluid flow model of the Bocca Grande and and Bocca Nuova fumaroles using the TOUGH 2 code. Our results show that the distinct resistivity structure, temperature, and water content of the both fumaroles are due to the particular geometry of the condensate flow that intersects and contaminates the Bocca Nuova but not the Bocca Grande fumarole. These results indicate the necessity to combine geophysical and geochemical approaches in order to better apprehend the structure complexity and the dynamics of fumaroles and hydrothermal systems.

Dynamics of Electronically Excited Species in Gaseous and Condensed Phase

DTIC Science & Technology

1989-12-01

heatbath models of condensed phase helium, (3) development of models of condensed phase hydrogen and (4) development of simulation procedures for solution... Modelling and Computer Experiments 93 Introduction 93 Monte Carlo Simulations of Helium Bubble States 94 Heatbath Models f6r Helium Bubble States 114...ILLUSTRATIONS 1 He-He* potential energy curves and couplings for two-state model . 40 2 Cross section for He(1P) quenching to He( 3S) 42 3 Opacity

Results for the DWPF Slurry Mix Evaporator Condensate Tank, Off Gas Condensate Tank, And Recycle Collection Tank Samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

TERRI, FELLINGER

2004-12-21

The Defense Waste Processing Facility, DWPF, currently generates approximately 1.4 million gallons of recycle water per year during Sludge-Only operations. DWPF has minimized condensate generation to 1.4 million gallons by not operating the Steam Atomized Scrubbers, SASs, for the melter off gas system. By not operating the SASs, DWPF has reduced the total volume by approximately 800,000 gallons of condensate per year. Currently, the recycle stream is sent to back to the Tank Farm and processed through the 2H Evaporator system. To alleviate the load on the 2H Evaporator system, an acid evaporator design is being considered as an alternatemore » processing and/or concentration method for the DWPF recycle stream. In order to support this alternate processing option, the DWPF has requested that the chemical and radionuclide compositions of the Off Gas Condensate Tank, OGCT, Slurry Mix Evaporator Condensate Tank, SMECT, Recycle Collection Tank, RCT, and the Decontamination Waste Treatment Tank, DWTT, be determined as a part of the process development work for the acid evaporator design. Samples have been retrieved from the OGCT, RCT, and SMECT and have been sent to the Savannah River National Laboratory, SRNL for this characterization. The DWTT samples have been recently shipped to SRNL. The results for the DWTT samples will be issued at later date.« less

Using National Drug Codes and drug knowledge bases to organize prescription records from multiple sources.

PubMed

Simonaitis, Linas; McDonald, Clement J

2009-10-01

The utility of National Drug Codes (NDCs) and drug knowledge bases (DKBs) in the organization of prescription records from multiple sources was studied. The master files of most pharmacy systems include NDCs and local codes to identify the products they dispense. We obtained a large sample of prescription records from seven different sources. These records carried a national product code or a local code that could be translated into a national product code via their formulary master. We obtained mapping tables from five DKBs. We measured the degree to which the DKB mapping tables covered the national product codes carried in or associated with the sample of prescription records. Considering the total prescription volume, DKBs covered 93.0-99.8% of the product codes from three outpatient sources and 77.4-97.0% of the product codes from four inpatient sources. Among the in-patient sources, invented codes explained 36-94% of the noncoverage. Outpatient pharmacy sources rarely invented codes, which comprised only 0.11-0.21% of their total prescription volume, compared with inpatient pharmacy sources for which invented codes comprised 1.7-7.4% of their prescription volume. The distribution of prescribed products was highly skewed, with 1.4-4.4% of codes accounting for 50% of the message volume and 10.7-34.5% accounting for 90% of the message volume. DKBs cover the product codes used by outpatient sources sufficiently well to permit automatic mapping. Changes in policies and standards could increase coverage of product codes used by inpatient sources.

Synthesis of New Thiazolyl Coupled Pyrazoles Bearing 2,4-Thiazolidinedionyl Pharmacophore and Their Anti-Inflammatory and Antibacterial Evaluation.

PubMed

Khillare, Lalit; Bhosle, Manisha; Bhalerao, Mahendra; Kharat, Kiran; Mane, Ramrao

2017-01-01

2, 4-Thiazolidinedione (TZD), pyrazole and thiazole heterocyclic rings exhibit a wide range of pharmacological activities. Medicinal chemists use these heterocyclic moieties as scaffolds in drug designing and discovery. The existing medicaments, celecoxib and meloxicam, used for treating inflammation and pain are having, pyrazole and thiazole, respectively as key scaffolds. Pyrazoles coupled with 2, 4-thiazolidinediones may display enhanced anti-inflammatory activity. With this hope the bench work was carried out. Heterocyclic aldehydes, 3-(4-methyl-2-substituted thiazol-5-yl)-1-phenyl-1Hpyrazole- 4- carbaldehydes (4a-b) have been allowed to undergo Knoevenagel condensation with N-substituted 2,4-thiazolidinediones (5a-e) in PEG-400 in the presence of L-proline at 110°C and obtained the condensed products (6a-j). COX-2 evaluation of the titled product has been carried out using in vitro COX-2 ELISA Kit. Antibacterial activity of these compounds (6a-j) has also been determined. On the basis of 1H NMR, 13C NMR and Mass spectral data of the condensed products the structures have been assigned to (Z)-5-((3-(4-methyl-2-substituted thiazol-5-yl)-1- phenyl-1H-pyrazol-4-yl)methylene) 3-substituted thiazolidine-2,4-diones (6a-j). Among the evaluated compounds (6a-j), 6f, 6g, 6h, 6i and 6j have shown notable COX-2 inhibitory activity. Compounds, 6a, 6b, 6c, 6d, 6e and 6f have inhibited the growth of the Bacillus cereus NCIM 2106, Bacillus subtilis NCIM 2063, Pseudomonas aeruginosa NCIM 2074, Salmonella typhimurium NCIM 2501 and Staphylococcus aureus NCIM 2079. However, compound 6f has emerged as a suitable candidate with dual properties i.e. COX-2 inhibitory and antibacterial in the present study. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Effect of inhaled corticosteroid treatment on exhaled breath condensate leukotriene E(4) in children with mild asthma.

PubMed

Steiss, Jens-Oliver; Rudloff, Silvia; Landmann, Eva; Rückes-Nilges, Claudia; Zimmer, Klaus-Peter; Lindemann, Herrmann

2008-01-01

Chronic airway inflammation in children with asthma might be present even in the absence of pathological lung function tests and is known to increase the risk of permanent pulmonary damage. Thus, we aimed at investigating to what extent inflammatory markers such as leukotrienes (LTs) in exhaled breath condensate (EBC) or fractional exhaled nitric oxide (FE(NO)) reflect therapeutic effects in these patients. Fifty steroid-naive patients (aged 8.8 +/- 2.7 years) were included in the study. EBC was collected before and 6 months after therapy with inhaled corticosteroids. LTs were determined by using commercially available ELISA. In addition, FE(NO) was measured by means of a chemiluminescence analyzer. Conventional lung function testing was performed revealing vital capacity, forced expiratory volume, maximum expiratory flow, and specific resistance. In EBC, LTE(4) but not LTB(4) levels significantly decreased after steroid therapy from 45.3 +/- 36.0 pg/mL to 17.2 +/- 11.4 pg/mL (p < 0.0001) concomitant with a slight, but significant improvement of lung function parameters. Mean FE(NO) also indicated therapeutic success; however, in 20 of 50 patients, exhaled NO concentrations were higher after therapy. These findings suggest that LTE(4) in breath condensate may be helpful in latent inflammatory activity in the bronchial mucosa in children with asthma.

Microwave discharge electrodeless lamps (MDEL). Part IV. Novel self-ignition system incorporating metallic microwave condensing cones to activate MDELs in photochemical reactions.

PubMed

Horikoshi, Satoshi; Tsuchida, Akihiro; Sakai, Hideki; Abe, Masahiko; Sato, Susumu; Serpone, Nick

2009-11-01

A metallic condensing cone that concentrates microwave radiation (equivalent to an optical lens) has been developed and used as part of a system to activate a microwave discharge electrodeless lamp (MDEL) in the oxidative treatment of wastewaters by aiding the novel self-ignition of the lamp on irradiation at low microwave power levels. This approach to self-ignition can potentially lead to considerable energy savings in such treatments. System performance was examined for the ignition power of microwaves of such MDEL devices in water, whose usefulness was assessed by investigating the photolytic transformation of aqueous solutions of representatives of three classes of contaminants: chlorinated phenols, herbicides and endocrine disruptors, specifically 4-chlorophenol (4-CP), 2,4-dichlorophenoxyacetic acid (2,4-D) and 4,4'-isopropylidenediphenol (bisphenol-A; BPA), respectively, taken as model wastewaters in air-equilibrated, in oxygen-saturated and in TiO2-containing aqueous media. The results are discussed in terms of the dynamics of the photo-induced degradation processes.

7 CFR 1767.27 - Operation and maintenance expenses.

Code of Federal Regulations, 2012 CFR

2012-01-01

... turbines, engines, generators, and exciters. 3. Operating condensers, circulating water systems, and other... prime mover. 3. Hotwell pump outlet on condensate lines. 4. Inlet flange of all turbine-room auxiliaries... in operating turbogenerators, steam turbines and their auxiliary apparatus, switch gear, and other...

7 CFR 1767.27 - Operation and maintenance expenses.

Code of Federal Regulations, 2011 CFR

2011-01-01

... turbines, engines, generators, and exciters. 3. Operating condensers, circulating water systems, and other... prime mover. 3. Hotwell pump outlet on condensate lines. 4. Inlet flange of all turbine-room auxiliaries... in operating turbogenerators, steam turbines and their auxiliary apparatus, switch gear, and other...

7 CFR 1767.27 - Operation and maintenance expenses.

Code of Federal Regulations, 2010 CFR

2010-01-01

... turbines, engines, generators, and exciters. 3. Operating condensers, circulating water systems, and other... prime mover. 3. Hotwell pump outlet on condensate lines. 4. Inlet flange of all turbine-room auxiliaries... in operating turbogenerators, steam turbines and their auxiliary apparatus, switch gear, and other...

7 CFR 1767.27 - Operation and maintenance expenses.

Code of Federal Regulations, 2013 CFR

2013-01-01

... turbines, engines, generators, and exciters. 3. Operating condensers, circulating water systems, and other... prime mover. 3. Hotwell pump outlet on condensate lines. 4. Inlet flange of all turbine-room auxiliaries... in operating turbogenerators, steam turbines and their auxiliary apparatus, switch gear, and other...

7 CFR 1767.27 - Operation and maintenance expenses.

Code of Federal Regulations, 2014 CFR

2014-01-01

... turbines, engines, generators, and exciters. 3. Operating condensers, circulating water systems, and other... prime mover. 3. Hotwell pump outlet on condensate lines. 4. Inlet flange of all turbine-room auxiliaries... in operating turbogenerators, steam turbines and their auxiliary apparatus, switch gear, and other...

Dust around the Cool Component of D-Type Symbiotic Binaries

NASA Astrophysics Data System (ADS)

Jurkic, Tomislav; Kotnik-Karuza, Dubravka

2018-04-01

D type symbiotic binaries are an excellent astrophysical laboratory for investigation of the dust properties and dust formation under the influence of theMira stellar wind and nova activity and of the mass loss and mass transfer between components in such a widely separated system. We present a study of the properties of circumstellar dust in symbiotic Miras by use of long-term near-IR photometry and colour indices. The published JHKL magnitudes of o Ceti, RX Pup, KM Vel, V366 Car, V835 Cen, RR Tel, HM Sge and R Aqr have been collected, analyzed and corrected for short-term variations caused by Mira pulsations. Assuming spherical temperature distribution of the dust in the close neighbourhood of the Mira, the DUSTY code was used to solve the radiative transfer in order to determine the dust temperature and its properties in each particular case. Common dust properties of the symbiotic Miras have been found, suggesting similar conditions in the condensation region of the studied symbiotic Miras. Silicate dust with the inner dust shell radius determined by the dust condensation and with the dust temperature of 900-1200 K can fully explain the observed colour indices. R Aqr is an exception and showed lower dust temperature of 650 K. Obscuration events visible in light curves can be explained by variable dust optical depth with minimal variations of other dust properties. More active symbioticMiras that underwent recent nova outbursts showed higher dust optical depths and larger maximum grain sizes of the order of μm, which means that the post-nova activity could stimulate the dust formation and the grain growth. Optically thicker dust shells and higher dust condensation temperatures have been found in symbiotic Miras compared to their single counterparts, suggesting different conditions for dust production.

Qualitative content analysis in nursing research: concepts, procedures and measures to achieve trustworthiness.

PubMed

Graneheim, U H; Lundman, B

2004-02-01

Qualitative content analysis as described in published literature shows conflicting opinions and unsolved issues regarding meaning and use of concepts, procedures and interpretation. This paper provides an overview of important concepts (manifest and latent content, unit of analysis, meaning unit, condensation, abstraction, content area, code, category and theme) related to qualitative content analysis; illustrates the use of concepts related to the research procedure; and proposes measures to achieve trustworthiness (credibility, dependability and transferability) throughout the steps of the research procedure. Interpretation in qualitative content analysis is discussed in light of Watzlawick et al.'s [Pragmatics of Human Communication. A Study of Interactional Patterns, Pathologies and Paradoxes. W.W. Norton & Company, New York, London] theory of communication.

Micro-CT evaluation of the effectiveness of the combined use of rotary and hand instrumentation in removal of Resilon.

PubMed

Asheibi, Fatma; Qualtrough, Alison J E; Mellor, Anthony; Withers, Philip J; Lowe, Tristan

2014-01-01

This study compares the effectiveness of ProTaper rotary files with ProTaper retreatment and K-files in the removal of Resilon or gutta percha (GP) from canals filled either by cold lateral condensation or thermal obturation using micro-CT. Ninety-six teeth were prepared using ProTaper files and allocated into four groups (n=24): Group-1 was filled with GP/AH-Plus and Group-2 with Resilon/RealSeal using cold lateral condensation. Group-3 was filled with GP/AH-Plus and Group-4 with Resilon/RealSeal using System B and Obtura II. The roots were scanned by micro-CT. Each group was divided into two subgroups (n=12): A, retreated using ProTaper files and B, using ProTaper retreatment and K-files. The roots were scanned to calculate the volume of the remaining material. With thermal obturation, roots filled with Resilon had significantly more remaining material than GP. Obturation using thermal technique resulted in significantly less remaining material than cold condensation except Resilon retreated using ProTaper retreatment and K-files.

Stochastic hyperfine interactions modeling library

NASA Astrophysics Data System (ADS)

Zacate, Matthew O.; Evenson, William E.

2011-04-01

The stochastic hyperfine interactions modeling library (SHIML) provides a set of routines to assist in the development and application of stochastic models of hyperfine interactions. The library provides routines written in the C programming language that (1) read a text description of a model for fluctuating hyperfine fields, (2) set up the Blume matrix, upon which the evolution operator of the system depends, and (3) find the eigenvalues and eigenvectors of the Blume matrix so that theoretical spectra of experimental techniques that measure hyperfine interactions can be calculated. The optimized vector and matrix operations of the BLAS and LAPACK libraries are utilized; however, there was a need to develop supplementary code to find an orthonormal set of (left and right) eigenvectors of complex, non-Hermitian matrices. In addition, example code is provided to illustrate the use of SHIML to generate perturbed angular correlation spectra for the special case of polycrystalline samples when anisotropy terms of higher order than A can be neglected. Program summaryProgram title: SHIML Catalogue identifier: AEIF_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIF_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU GPL 3 No. of lines in distributed program, including test data, etc.: 8224 No. of bytes in distributed program, including test data, etc.: 312 348 Distribution format: tar.gz Programming language: C Computer: Any Operating system: LINUX, OS X RAM: Varies Classification: 7.4 External routines: TAPP [1], BLAS [2], a C-interface to BLAS [3], and LAPACK [4] Nature of problem: In condensed matter systems, hyperfine methods such as nuclear magnetic resonance (NMR), Mössbauer effect (ME), muon spin rotation (μSR), and perturbed angular correlation spectroscopy (PAC) measure electronic and magnetic structure within Angstroms of nuclear probes through the hyperfine interaction. When interactions fluctuate at rates comparable to the time scale of a hyperfine method, there is a loss in signal coherence, and spectra are damped. The degree of damping can be used to determine fluctuation rates, provided that theoretical expressions for spectra can be derived for relevant physical models of the fluctuations. SHIML provides routines to help researchers quickly develop code to incorporate stochastic models of fluctuating hyperfine interactions in calculations of hyperfine spectra. Solution method: Calculations are based on the method for modeling stochastic hyperfine interactions for PAC by Winkler and Gerdau [5]. The method is extended to include other hyperfine methods following the work of Dattagupta [6]. The code provides routines for reading model information from text files, allowing researchers to develop new models quickly without the need to modify computer code for each new model to be considered. Restrictions: In the present version of the code, only methods that measure the hyperfine interaction on one probe spin state, such as PAC, μSR, and NMR, are supported. Running time: Varies

Calibration of the pressure sensitivity of microphones by a free-field method at frequencies up to 80 khz.

PubMed

Zuckerwar, Allan J; Herring, G C; Elbing, Brian R

2006-01-01

A free-field (FF) substitution method for calibrating the pressure sensitivity of microphones at frequencies up to 80 kHz is demonstrated with both grazing and normal-incidence geometries. The substitution-based method, as opposed to a simultaneous method, avoids problems associated with the nonuniformity of the sound field and, as applied here, uses a 1/4-in. air-condenser pressure microphone as a known reference. Best results were obtained with a centrifugal fan, which is used as a random, broadband sound source. A broadband source minimizes reflection-related interferences that can plague FF measurements. Calibrations were performed on 1/4-in. FF air-condenser, electret, and microelectromechanical systems (MEMS) microphones in an anechoic chamber. The uncertainty of this FF method is estimated by comparing the pressure sensitivity of an air-condenser FF microphone, as derived from the FF measurement, with that of an electrostatic actuator calibration. The root-mean-square difference is found to be +/- 0.3 dB over the range 1-80 kHz, and the combined standard uncertainty of the FF method, including other significant contributions, is +/- 0.41 dB.

Full Configuration Interaction Quantum Monte Carlo and Diffusion Monte Carlo: A Comparative Study of the 3D Homogeneous Electron Gas

NASA Astrophysics Data System (ADS)

Shepherd, James J.; López Ríos, Pablo; Needs, Richard J.; Drummond, Neil D.; Mohr, Jennifer A.-F.; Booth, George H.; Grüneis, Andreas; Kresse, Georg; Alavi, Ali

2013-03-01

Full configuration interaction quantum Monte Carlo1 (FCIQMC) and its initiator adaptation2 allow for exact solutions to the Schrödinger equation to be obtained within a finite-basis wavefunction ansatz. In this talk, we explore an application of FCIQMC to the homogeneous electron gas (HEG). In particular we use these exact finite-basis energies to compare with approximate quantum chemical calculations from the VASP code3. After removing the basis set incompleteness error by extrapolation4,5, we compare our energies with state-of-the-art diffusion Monte Carlo calculations from the CASINO package6. Using a combined approach of the two quantum Monte Carlo methods, we present the highest-accuracy thermodynamic (infinite-particle) limit energies for the HEG achieved to date. 1 G. H. Booth, A. Thom, and A. Alavi, J. Chem. Phys. 131, 054106 (2009). 2 D. Cleland, G. H. Booth, and A. Alavi, J. Chem. Phys. 132, 041103 (2010). 3 www.vasp.at (2012). 4 J. J. Shepherd, A. Grüneis, G. H. Booth, G. Kresse, and A. Alavi, Phys. Rev. B. 86, 035111 (2012). 5 J. J. Shepherd, G. H. Booth, and A. Alavi, J. Chem. Phys. 136, 244101 (2012). 6 R. Needs, M. Towler, N. Drummond, and P. L. Ríos, J. Phys.: Condensed Matter 22, 023201 (2010).

Wave fluctuations in the system with some Yang-Mills condensates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prokhorov, G., E-mail: zhoraprox@yandex.ru; Pasechnik, R., E-mail: Roman.Pasechnik@thep.lu.se; Vereshkov, G., E-mail: gveresh@gmail.com

2016-12-15

Self-consistent dynamics of non-homogeneous fluctuations and homogeneous and isotropic condensate of Yang–Mills fields was investigated in zero, linear and quasilinear approximations over the wave modes in the framework of N = 4 supersymmetric model in Hamilton gauge in quasiclassical theory. The models with SU(2), SU(3) and SU(4) gauge groups were considered. Particle production effect and effect of generation of longitudinal oscillations were obtained.

Cloud Atlas: Rotational Modulations in the L/T Transition Brown Dwarf Companion HN Peg B

NASA Technical Reports Server (NTRS)

Zhou, Yifan; Apai, Daniel; Metchev, Stanimir; Lew, Ben W. P.; Schneider, Glenn; Marley, Mark S.; Karalidi, Theodora; Manjavacas, Elena; Bedin, Luigi R.; Cowan, Nicolas B.;

Performance of MIMO-OFDM using convolution codes with QAM modulation

NASA Astrophysics Data System (ADS)

Astawa, I. Gede Puja; Moegiharto, Yoedy; Zainudin, Ahmad; Salim, Imam Dui Agus; Anggraeni, Nur Annisa

2014-04-01

Performance of Orthogonal Frequency Division Multiplexing (OFDM) system can be improved by adding channel coding (error correction code) to detect and correct errors that occur during data transmission. One can use the convolution code. This paper present performance of OFDM using Space Time Block Codes (STBC) diversity technique use QAM modulation with code rate ½. The evaluation is done by analyzing the value of Bit Error Rate (BER) vs Energy per Bit to Noise Power Spectral Density Ratio (Eb/No). This scheme is conducted 256 subcarrier which transmits Rayleigh multipath fading channel in OFDM system. To achieve a BER of 10-3 is required 10dB SNR in SISO-OFDM scheme. For 2×2 MIMO-OFDM scheme requires 10 dB to achieve a BER of 10-3. For 4×4 MIMO-OFDM scheme requires 5 dB while adding convolution in a 4x4 MIMO-OFDM can improve performance up to 0 dB to achieve the same BER. This proves the existence of saving power by 3 dB of 4×4 MIMO-OFDM system without coding, power saving 7 dB of 2×2 MIMO-OFDM and significant power savings from SISO-OFDM system.

RELAP5-3D Developmental Assessment: Comparison of Versions 4.2.1i and 4.1.3i

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayless, Paul D.

2014-06-01

Figures have been generated comparing the parameters used in the developmental assessment of the RELAP5-3D code using versions 4.2.1i and 4.1.3i. The figures, which are the same as those used in Volume III of the RELAP5-3D code manual, compare calculations using the semi-implicit solution scheme with available experiment data. These figures provide a quick, visual indication of how the code predictions changed between these two code versions and can be used to identify cases in which the assessment judgment may need to be changed in Volume III of the code manual. Changes to the assessment judgments made after reviewing allmore » of the assessment cases are also provided.« less

Gravitationally Driven Wicking for Enhanced Condensation Heat Transfer.

PubMed

Preston, Daniel J; Wilke, Kyle L; Lu, Zhengmao; Cruz, Samuel S; Zhao, Yajing; Becerra, Laura L; Wang, Evelyn N

2018-04-17

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Filmwise condensation is prevalent in typical industrial-scale systems, where the condensed fluid forms a thin liquid film due to the high surface energy associated with many industrial materials. Conversely, dropwise condensation, where the condensate forms discrete liquid droplets which grow, coalesce, and shed, results in an improvement in heat transfer performance of an order of magnitude compared to filmwise condensation. However, current state-of-the-art dropwise technology relies on functional hydrophobic coatings, for example, long chain fatty acids or polymers, which are often not robust and therefore undesirable in industrial conditions. In addition, low surface tension fluid condensates, such as hydrocarbons, pose a unique challenge because common hydrophobic condenser coatings used to shed water (with a surface tension of 73 mN/m) often do not repel fluids with lower surface tensions (<25 mN/m). We demonstrate a method to enhance condensation heat transfer using gravitationally driven flow through a porous metal wick, which takes advantage of the condensate's affinity to wet the surface and also eliminates the need for condensate-phobic coatings. The condensate-filled wick has a lower thermal resistance than the fluid film observed during filmwise condensation, resulting in an improved heat transfer coefficient of up to an order of magnitude and comparable to that observed during dropwise condensation. The improved heat transfer realized by this design presents the opportunity for significant energy savings in natural gas processing, thermal management, heating and cooling, and power generation.

Recent Advances in Modeling Hugoniots with Cheetah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glaesemann, K R; Fried, L E

2005-07-26

We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.

Recent Advances in Modeling Hugoniots with Cheetah

NASA Astrophysics Data System (ADS)

Glaesemann, K. R.; Fried, L. E.

2006-07-01

We describe improvements to the Cheetah thermochemical-kinetics code's equilibrium solver to enable it to find a wider range of thermodynamic states. Cheetah supports a wide range of elements, condensed detonation products, and gas phase reactions. Therefore, Cheetah can be applied to a wide range of shock problems involving both energetic and non-energetic materials. An improve equation of state is also introduced. New experimental validations of Cheetah's equation of state methodology have been performed, including both reacted and unreacted Hugoniots.

Mixing, Combustion, and Other Interface Dominated Flows; Paragraphs 3.2.1 A, B, C and 3.2.2 A

DTIC Science & Technology

2014-04-09

Condensed Matter Physics , (12 2010): 43401. doi: H. Lim, Y. Yu, J. Glimm, X. L. Li, D.H. Sharp. Subgrid Models for Mass and Thermal Diffusion in...zone and a series of radial cracks in solid plates hit by high velocity projectiles). • Only 2D dimensional models • Serial codes for running on single ...exter- nal parallel packages TAO and Global Arrays, developed within DOE high performance computing initiatives. A Schwartz-type overlapping domain

Criterions for condensation-free flow in supersonic tunnels

NASA Technical Reports Server (NTRS)

Burgess, Warren C; Seashore, Ferris L

1949-01-01

The results of an investigation of water-vapor condensation shocks in the air passing through supersonic tunnels are presented. Criterions for condensation-free flow are established by correlating experimental observations with the Volmer theory of nuclei formation. Experimental observations were made at Mach numbers up to 2.01. The criterions are presented in a form independent of tunnel-inlet stagnation pressure and are extended theoretically to a Mach number of 4.00. Preliminary evidence of the effect of tunnel size on the criterion is presented.

One-pot aldol condensation and hydrodeoxygenation of biomass-derived carbonyl compounds for biodiesel synthesis.

PubMed

Faba, Laura; Díaz, Eva; Ordóñez, Salvador

2014-10-01

Integrating reaction steps is of key interest in the development of processes for transforming lignocellulosic materials into drop-in fuels. We propose a procedure for performing the aldol condensation (reaction between furfural and acetone is taken as model reaction) and the total hydrodeoxygenation of the resulting condensation adducts in one step, yielding n-alkanes. Different combinations of catalysts (bifunctional catalysts or mechanical mixtures), reaction conditions, and solvents (aqueous and organic) have been tested for performing these reactions in an isothermal batch reactor. The results suggest that the use of bifunctional catalysts and aqueous phase lead to an effective integration of both reactions. Therefore, selectivities to n-alkanes higher than 50% were obtained using this catalyst at typical hydrogenation conditions (T=493 K, P=4.5 MPa, 24 h reaction time). The use of organic solvent, carbonaceous supports, or mechanical mixtures of monofunctional catalysts leads to poorer results owing to side effects; mainly, hydrogenation of reactants and adsorption processes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CoFlame: A refined and validated numerical algorithm for modeling sooting laminar coflow diffusion flames

NASA Astrophysics Data System (ADS)

Eaves, Nick A.; Zhang, Qingan; Liu, Fengshan; Guo, Hongsheng; Dworkin, Seth B.; Thomson, Murray J.

2016-10-01

Mitigation of soot emissions from combustion devices is a global concern. For example, recent EURO 6 regulations for vehicles have placed stringent limits on soot emissions. In order to allow design engineers to achieve the goal of reduced soot emissions, they must have the tools to so. Due to the complex nature of soot formation, which includes growth and oxidation, detailed numerical models are required to gain fundamental insights into the mechanisms of soot formation. A detailed description of the CoFlame FORTRAN code which models sooting laminar coflow diffusion flames is given. The code solves axial and radial velocity, temperature, species conservation, and soot aggregate and primary particle number density equations. The sectional particle dynamics model includes nucleation, PAH condensation and HACA surface growth, surface oxidation, coagulation, fragmentation, particle diffusion, and thermophoresis. The code utilizes a distributed memory parallelization scheme with strip-domain decomposition. The public release of the CoFlame code, which has been refined in terms of coding structure, to the research community accompanies this paper. CoFlame is validated against experimental data for reattachment length in an axi-symmetric pipe with a sudden expansion, and ethylene-air and methane-air diffusion flames for multiple soot morphological parameters and gas-phase species. Finally, the parallel performance and computational costs of the code is investigated.

Studies on the self-catalyzed Knoevenagel condensation, characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques

NASA Astrophysics Data System (ADS)

Suresh Kumar, G. S.; Antony Muthu Prabhu, A.; Bhuvanesh, N.

2014-10-01

We have studied the self-catalyzed Knoevenagel condensation, spectral characterization, DPPH radical scavenging activity, cytotoxicity, and molecular properties of 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones using single crystal XRD and DFT techniques. In the absence of any catalyst, a series of novel 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones were synthesized using Meldrum’s acid and formylphenoxyaliphatic acid(s) in water. These molecules are arranged in the dimer form through intermolecular H-bonding in the single crystal XRD structure. Compounds have better DPPH radical scavenging activity and cytotoxicity against A431 cancer cell line. The optimized molecular structure, natural bond orbital analysis, electrostatic potential map, HOMO-LUMO energies, molecular properties, and atomic charges of these molecules have been studied by performing DFT/B3LYP/3-21G(*) level of theory in gas phase.

Evaluation of four-dimensional nonbinary LDPC-coded modulation for next-generation long-haul optical transport networks.

PubMed

Zhang, Yequn; Arabaci, Murat; Djordjevic, Ivan B

2012-04-09

Leveraging the advanced coherent optical communication technologies, this paper explores the feasibility of using four-dimensional (4D) nonbinary LDPC-coded modulation (4D-NB-LDPC-CM) schemes for long-haul transmission in future optical transport networks. In contrast to our previous works on 4D-NB-LDPC-CM which considered amplified spontaneous emission (ASE) noise as the dominant impairment, this paper undertakes transmission in a more realistic optical fiber transmission environment, taking into account impairments due to dispersion effects, nonlinear phase noise, Kerr nonlinearities, and stimulated Raman scattering in addition to ASE noise. We first reveal the advantages of using 4D modulation formats in LDPC-coded modulation instead of conventional two-dimensional (2D) modulation formats used with polarization-division multiplexing (PDM). Then we demonstrate that 4D LDPC-coded modulation schemes with nonbinary LDPC component codes significantly outperform not only their conventional PDM-2D counterparts but also the corresponding 4D bit-interleaved LDPC-coded modulation (4D-BI-LDPC-CM) schemes, which employ binary LDPC codes as component codes. We also show that the transmission reach improvement offered by the 4D-NB-LDPC-CM over 4D-BI-LDPC-CM increases as the underlying constellation size and hence the spectral efficiency of transmission increases. Our results suggest that 4D-NB-LDPC-CM can be an excellent candidate for long-haul transmission in next-generation optical networks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mauro, R.; Leach, S.

This paper summarizes current and planned activities in the areas of hydrogen production and use, near-term venture opportunities, and codes and standards. The rationale for these efforts is to assess industry interest and engage in activities that move hydrogen technologies down the path to commercialization. Some of the work presented in this document is a condensed, preliminary version of reports being prepared under the DOE/NREL contract. In addition, the NHA work funded by Westinghouse Savannah River Corporation (WSRC) to explore the opportunities and industry interest in a Hydrogen Research Center is briefly described. Finally, the planned support of and industrymore » input to the Hydrogen Technical Advisory Panel (HTAP) on hydrogen demonstration projects is discussed.« less

The role of beta-ketoacyl-acyl carrier protein synthase III in the condensation steps of fatty acid biosynthesis in sunflower.

PubMed

González-Mellado, Damián; von Wettstein-Knowles, Penny; Garcés, Rafael; Martínez-Force, Enrique

2010-05-01

The beta-ketoacyl-acyl carrier protein synthase III (KAS III; EC 2.3.1.180) is a condensing enzyme catalyzing the initial step of fatty acid biosynthesis using acetyl-CoA as primer. To determine the mechanisms involved in the biosynthesis of fatty acids in sunflower (Helianthus annuus L.) developing seeds, a cDNA coding for HaKAS III (EF514400) was isolated, cloned and sequenced. Its protein sequence is as much as 72% identical to other KAS III-like ones such as those from Perilla frutescens, Jatropha curcas, Ricinus communis or Cuphea hookeriana. Phylogenetic study of the HaKAS III homologous proteins infers its origin from cyanobacterial ancestors. A genomic DNA gel blot analysis revealed that HaKAS III is a single copy gene. Expression levels of this gene, examined by Q-PCR, revealed higher levels in developing seeds storing oil than in leaves, stems, roots or seedling cotyledons. Heterologous expression of HaKAS III in Escherichia coli altered their fatty acid content and composition implying an interaction of HaKAS III with the bacterial FAS complex. Testing purified HaKAS III recombinant protein by adding to a reconstituted E. coli FAS system lacking condensation activity revealed a novel substrate specificity. In contrast to all hitherto characterized plant KAS IIIs, the activities of which are limited to the first cycles of intraplastidial fatty acid biosynthesis yielding C6 chains, HaKAS III participates in at least four cycles resulting in C10 chains.

Impacts of New Particle Formation on Midwestern Climate and Air Quality as Determined by the NPF-explicit WRF-Chem

NASA Astrophysics Data System (ADS)

Dong, C.; Stanier, C. O.; Bullard, R.; Singh, A.

2016-12-01

A one month simulation has been performed using the New particle formation (NPF)-explicit WRF-Chem (Matsui et al, Journal of Geophysical Research, 116(D19208), 2011). The simulation was run for a domain of the continental United States, with analysis focused on the Midwestern and eastern portions of the U.S. Analysis focused on quantification and explanation of planetary boundary layer (PBL) NPF in the model on variables beyond condensation nuclei (CN), cloud condensation nuclei (CCN), and cloud droplet size distributions. The model was evaluated against meteorology, chemical species and aerosol physical property observations. Comparison shows the model performance was comparable to that of other studies. Nucleation enhanced the concentration of condensation nuclei (CN). Cloud condensation nuclei (CCN) concentrations were enhanced and suppressed at high and low supersaturations, respectively. For air pollutants, the most pronounced influence of PBL nucleation was PM2.5 reduction, which was mainly caused by SO4 decreases (62.7%). For shortwave radiation, changes due to indirect effects of NPF were larger than direct effects. Shortwave radiation and cloud droplet concentration typically changed in the same way. Similar change patterns were found for T2 and PBL height. PBL nucleation led to a net increase of precipitation during the simulation period. Sensitivity tests showed that the combination of PBL NPF together with aqueous chemistry was the predominant cause of SO4 reduction.

Presence of tannins in sorghum grains is conditioned by different natural alleles of Tannin1

PubMed Central

Wu, Yuye; Li, Xianran; Xiang, Wenwen; Zhu, Chengsong; Lin, Zhongwei; Wu, Yun; Li, Jiarui; Pandravada, Satchidanand; Ridder, Dustan D.; Bai, Guihua; Wang, Ming L.; Trick, Harold N.; Bean, Scott R.; Tuinstra, Mitchell R.; Tesso, Tesfaye T.; Yu, Jianming

2012-01-01

Sorghum, an ancient old-world cereal grass, is the dietary staple of over 500 million people in more than 30 countries in the tropics and semitropics. Its C4 photosynthesis, drought resistance, wide adaptation, and high nutritional value hold the promise to alleviate hunger in Africa. Not present in other major cereals, such as rice, wheat, and maize, condensed tannins (proanthocyanidins) in the pigmented testa of some sorghum cultivars have been implicated in reducing protein digestibility but recently have been shown to promote human health because of their high antioxidant capacity and ability to fight obesity through reduced digestion. Combining quantitative trait locus mapping, meta-quantitative trait locus fine-mapping, and association mapping, we showed that the nucleotide polymorphisms in the Tan1 gene, coding a WD40 protein, control the tannin biosynthesis in sorghum. A 1-bp G deletion in the coding region, causing a frame shift and a premature stop codon, led to a nonfunctional allele, tan1-a. Likewise, a different 10-bp insertion resulted in a second nonfunctional allele, tan1-b. Transforming the sorghum Tan1 ORF into a nontannin Arabidopsis mutant restored the tannin phenotype. In addition, reduction in nucleotide diversity from wild sorghum accessions to landraces and cultivars was found at the region that codes the highly conserved WD40 repeat domains and the C-terminal region of the protein. Genetic research in crops, coupled with nutritional and medical research, could open the possibility of producing different levels and combinations of phenolic compounds to promote human health. PMID:22699509

Numerical Issues Associated with Compensating and Competing Processes in Climate Models: an Example from ECHAM-HAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, Hui; Rasch, Philip J.; Zhang, Kai

2013-06-26

The purpose of this paper is to draw attention to the need for appropriate numerical techniques to represent process interactions in climate models. In two versions of the ECHAM-HAM model, different time integration methods are used to solve the sulfuric acid (H2SO4) gas evolution equation, which lead to substantially different results in the H2SO4 gas concentration and the aerosol nucleation rate. Using convergence tests and sensitivity simulations performed with various time stepping schemes, it is confirmed that numerical errors in the second model version are significantly smaller than those in version one. The use of sequential operator splitting in combinationmore » with long time step is identified as the main reason for the large systematic biases in the old model. The remaining errors in version two in the nucleation rate, related to the competition between condensation and nucleation, have a clear impact on the simulated concentration of cloud condensation nuclei in the lower troposphere. These errors can be significantly reduced by employing an implicit solver that handles production, condensation and nucleation at the same time. Lessons learned in this work underline the need for more caution when treating multi-time-scale problems involving compensating and competing processes, a common occurrence in current climate models.« less

Simulation of homogeneous condensation of small polyatomic systems in high pressure supersonic nozzle flows using Bhatnagar-Gross-Krook model

NASA Astrophysics Data System (ADS)

Kumar, Rakesh; Levin, Deborah A.

2011-03-01

In the present work, we have simulated the homogeneous condensation of carbon dioxide and ethanol using the Bhatnagar-Gross-Krook based approach. In an earlier work of Gallagher-Rogers et al. [J. Thermophys. Heat Transfer 22, 695 (2008)], it was found that it was not possible to simulate condensation experiments of Wegener et al. [Phys. Fluids 15, 1869 (1972)] using the direct simulation Monte Carlo method. Therefore, in this work, we have used the statistical Bhatnagar-Gross-Krook approach, which was found to be numerically more efficient than direct simulation Monte Carlo method in our previous studies [Kumar et al., AIAA J. 48, 1531 (2010)], to model homogeneous condensation of two small polyatomic systems, carbon dioxide and ethanol. A new weighting scheme is developed in the Bhatnagar-Gross-Krook framework to reduce the computational load associated with the study of homogeneous condensation flows. The solutions obtained by the use of the new scheme are compared with those obtained by the baseline Bhatnagar-Gross-Krook condensation model (without the species weighting scheme) for the condensing flow of carbon dioxide in the stagnation pressure range of 1-5 bars. Use of the new weighting scheme in the present work makes the simulation of homogeneous condensation of ethanol possible. We obtain good agreement between our simulated predictions for homogeneous condensation of ethanol and experiments in terms of the point of condensation onset and the distribution of mass fraction of ethanol condensed along the nozzle centerline.

Stormwater chemical contamination caused by cured-in-place pipe (CIPP) infrastructure rehabilitation activities.

PubMed

Tabor, Matthew L; Newman, Derrick; Whelton, Andrew J

2014-09-16

Cured-in-place pipe (CIPP) is becoming a popular U.S. stormwater culvert rehabilitation method. Several State transportation agencies have reported that CIPP activities can release styrene into stormwater, but no other contaminants have been monitored. CIPP's stormwater contamination potential and that of its condensate waste was characterized. Condensate completely dissolved Daphnia magna within 24 h. Condensate pH was 6.2 and its chemical oxygen demand (COD) level was 36,000 ppm. D. magna mortality (100%) occurred in 48 h, even when condensate was diluted by a factor of 10,000 and styrene was present at a magnitude less than its LC50. Condensate and stormwater contained numerous carcinogenic solvents used in resin synthesis, endocrine disrupting contaminants such as plasticizers, and initiator degradation products. For 35 days, COD levels at the culvert outlets and downstream ranged from 100 to 375 ppm and styrene was 0.01 to 7.4 ppm. Although contaminant levels generally reduced with time, styrene levels were greatest 50 ft downstream, not at the culvert outlet. Cured CIPP extraction tests confirmed that numerous contaminants other than styrene were released into the environment and their persistence and toxicity should be investigated. More effective contaminant containment and cleaner installation processes must be developed to protect the environment.

Rumex acetosa Y chromosomes: constitutive or facultative heterochromatin?

PubMed

Mosiołek, Magdalena; Pasierbek, Paweł; Malarz, Janusz; Moś, Maria; Joachimiak, Andrzej J

2005-01-01

Condensed Y chromosomes in Rumex acetosa L. root-tip nuclei were studied using 5-azaC treatment and immunohistochemical detection of methylated histones. Although Y chromosomes were decondensed within root meristem in vivo, they became condensed and heteropycnotic in roots cultured in vitro. 5-azacytidine (5-azaC) treatment of cultured roots caused transitional dispersion of their Y chromosome bodies, but 7 days after removal of the drug from the culture medium, Y heterochromatin recondensed and again became visible. The response of Rumex sex chromatin to 5-azaC was compared with that of condensed segments of pericentromeric heterochromatin in Rhoeo spathacea (Sw.) Steam roots. It was shown that Rhoeo chromocentres, composed of AT-rich constitutive heterochromatin, did not undergo decondensation after 5-azaC treatment. The Y-bodies observed within male nuclei of R. acetosa were globally enriched with H3 histone, demethylated at lysine 4 and methylated at lysine 9. This is the first report of histone tail-modification in condensed sex chromatin in plants. Our results suggest that the interphase condensation of Y chromosomes in Rumex is facultative rather than constitutive. Furthermore, the observed response of Y-bodies to 5-azaC may result indirectly from demethylation and the subsequent altered expression of unknown genes controlling tissue-specific Y-inactivation as opposed to the global demethylation of Y-chromosome DNA.

Raman Scattering from Higgs Mode Oscillations in the Two-Dimensional Antiferromagnet Ca_{2}RuO_{4}.

PubMed

Souliou, Sofia-Michaela; Chaloupka, Jiří; Khaliullin, Giniyat; Ryu, Gihun; Jain, Anil; Kim, B J; Le Tacon, Matthieu; Keimer, Bernhard

2017-08-11

We present and analyze Raman spectra of the Mott insulator Ca_{2}RuO_{4}, whose quasi-two-dimensional antiferromagnetic order has been described as a condensate of low-lying spin-orbit excitons with angular momentum J_{eff}=1. In the A_{g} polarization geometry, the amplitude (Higgs) mode of the spin-orbit condensate is directly probed in the scalar channel, thus avoiding infrared-singular magnon contributions. In the B_{1g} geometry, we observe a single-magnon peak as well as two-magnon and two-Higgs excitations. Model calculations using exact diagonalization quantitatively agree with the observations. Together with recent neutron scattering data, our study provides strong evidence for excitonic magnetism in Ca_{2}RuO_{4} and points out new perspectives for research on the Higgs mode in two dimensions.

Raman Scattering from Higgs Mode Oscillations in the Two-Dimensional Antiferromagnet Ca2RuO4

NASA Astrophysics Data System (ADS)

Souliou, Sofia-Michaela; Chaloupka, Jiří; Khaliullin, Giniyat; Ryu, Gihun; Jain, Anil; Kim, B. J.; Le Tacon, Matthieu; Keimer, Bernhard

2017-08-01

We present and analyze Raman spectra of the Mott insulator Ca2RuO4 , whose quasi-two-dimensional antiferromagnetic order has been described as a condensate of low-lying spin-orbit excitons with angular momentum Jeff=1 . In the Ag polarization geometry, the amplitude (Higgs) mode of the spin-orbit condensate is directly probed in the scalar channel, thus avoiding infrared-singular magnon contributions. In the B1 g geometry, we observe a single-magnon peak as well as two-magnon and two-Higgs excitations. Model calculations using exact diagonalization quantitatively agree with the observations. Together with recent neutron scattering data, our study provides strong evidence for excitonic magnetism in Ca2 RuO4 and points out new perspectives for research on the Higgs mode in two dimensions.

Oxidative condensation reactions of (diethylenetriamine)cobalt(III) complexes with substituted bis(pyridin-2-yl)methane ligands

NASA Astrophysics Data System (ADS)

Zhou, Xiangting; Hockless, David C. R.; Willis, Anthony C.; Jackson, W. Gregory

2005-04-01

The synthesis and characterisation of Co(III) complexes derived from a condensation reaction with a central or terminal nitrogen of a dien ligand and the α-carbon of a range of substituted bis(pyridin-2-yl)methane ligands are described. Aerial oxidation of bpm {bis(pyridin-2-yl)methane with Co(II)/dien or direct reaction with Co(dien)Cl 3 provided in low yield a single C-N condensation product 1 (at the primary terminal NH 2) after the pyridyl -CH 2- is formally oxidised to -CH +-. The methyl substituted ligand bpe {1,1-bis(pyridin-2-yl)ethane} behaves likewise, except both terminal (prim) and central (sec) amines condense to yield isomeric products 2 and 3. Two of these three materials have been characterised by single crystal X-ray crystallography. The corresponding reactions for the bis(pyridyl) ligand bpk {bis(pyridin-2-yl)ketone} provided C-N condensation products without the requirement for oxidation at the α-C center; two carbinolamine complexes in different geometrical configurations resulted, mer-anti-[Co(dienbpc)Cl]ZnCl 4, 5, and unsym- fac-[Co(dienbpc)Cl]ZnCl 4, 6, {dienbpc=[2-(2-aminoethylamino)-ethylamino]-di-pyridin-2-yl-methanol}. In addition, a novel complex, [Co(bpk)(bpd-OH)Cl]ZnCl 4, 4, in which one bidentate N, N-bonded bpk ligand and one tridentate N, O, N-bonded bpd (the diol from bpk+OH -) were coordinated, was obtained via the Co(II)/O 2 synthetic route. When the bpc ligand (bpc=bis(pyridin-2-yl)methanol) was employed directly as a reagent along with dien, no condensation reactions were observed, but rather a single isomeric complex [Co(dien)(bpc)]Cl.ZnCl 4, 7, in which the ligand bpc acted as a N,N,O-bonded tridentate ligand rather than as a N,N-bidentate ligand was isolated. 13C, 1D and 2D 1H NMR studies are reported for all the complexes; they establish the structures unambiguously.

High Temperature Alkali Corrosion of Dense SN4 Coated with CMZP and Mg-Doped A21TiO5 in Coal Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. J. Brown; Nguyen Thierry

1997-10-01

Si3N4 heat exchangers used in industrial systems are usually operating in harsh environments. Not only is this structural material experiencing high temperatures, but it is also subjected to corrosive gases and condensed phases. Past studies have demonstrated that condensed phases severely attack Si3N4 and as a consequence, dramatically reduce its lifetime in industrial operating systems.1,2 Previous research conducted at Virginia Tech on low thermal expansion coefficient oxide ceramics,3,4,5 (Ca1-X,MgX)Zr4(PO4)6 (CMZP), and Mg-doped Al2TiO5, for structural application have shown that these two materials exhibited better resistance to alkaline corrosion than Si3N4. Thus, they were envisioned as good candidates for a protectivemore » coating on Si3N4 heat exchangers. As a result, the goal of the present work is to develop CMZP and Mg-doped Al2TiO5 protective thin films using the sol-gel process and the dip coating technique and to test their effectiveness in an alkali-containing atmosphere.« less

Conceptual Design of a Condensing Heat Exchanger for Space Systems Using Porous Media

NASA Technical Reports Server (NTRS)

Hasan, Mohammad M.; Khan, Lutful I.; Nayagam, Vedha; Balasubramaniam, Ramaswamy

2006-01-01

Condensing heat exchangers are used in many space applications in the thermal and humidity control systems. In the International Space Station (ISS), humidity control is achieved by using a water cooled fin surface over which the moist air condenses, followed by "slurper bars" that take in both the condensate and air into a rotary separator and separates the water from air. The use of a cooled porous substrate as the condensing surface provides and attractive alternative that combines both heat removal as well as liquid/gas separation into a single unit. By selecting the pore sizes of the porous substrate a gravity independent operation may also be possible with this concept. Condensation of vapor into and on the porous surface from the flowing air and the removal of condensate from the porous substrate are the critical processes involved in the proposed concept. This paper describes some preliminary results of the proposed condensate withdrawal process and discusses the on-going design and development work of a porous media based condensing heat exchanger at the NASA Glenn Research Center in collaboration with NASA Johnson Space Center.

27 CFR 4.21 - The standards of identity.

Code of Federal Regulations, 2010 CFR

2010-04-01

... alcoholic fermentation of the juice of sound, ripe grapes (including restored or unrestored pure condensed grape must), with or without the addition, after fermentation, of pure condensed grape must, and with or... cellar treatment: Provided, That the product may be ameliorated before, during or after fermentation by...

Validation of the WIMSD4M cross-section generation code with benchmark results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leal, L.C.; Deen, J.R.; Woodruff, W.L.

1995-02-01

The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment for Research and Test (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code, WIMSD4M, very attractive, not only for the RERTR program, but also for the reactor physics community. The intent of the present paper is to validate the procedure to generatemore » cross-section libraries for reactor analyses and calculations utilizing the WIMSD4M code. To do so, the results of calculations performed with group cross-section data generated with the WIMSD4M code will be compared against experimental results. These results correspond to calculations carried out with thermal reactor benchmarks of the Oak Ridge National Laboratory(ORNL) unreflected critical spheres, the TRX critical experiments, and calculations of a modified Los Alamos highly-enriched heavy-water moderated benchmark critical system. The benchmark calculations were performed with the discrete-ordinates transport code, TWODANT, using WIMSD4M cross-section data. Transport calculations using the XSDRNPM module of the SCALE code system are also included. In addition to transport calculations, diffusion calculations with the DIF3D code were also carried out, since the DIF3D code is used in the RERTR program for reactor analysis and design. For completeness, Monte Carlo results of calculations performed with the VIM and MCNP codes are also presented.« less

Theoretical study on bubble formation and flow condensation in downflow channel with horizontal gas injection

NASA Astrophysics Data System (ADS)

Zhu, Kang; Li, Yanzhong; Wang, Jiaojiao; Ma, Yuan; Wang, Lei; Xie, Fushou

2018-05-01

Bubble formation and condensation in liquid pipes occur widely in industrial systems such as cryogenic propellant feeding system. In this paper, an integrated theoretical model is established to give a comprehensive description of the bubble formation, motion and condensation process. The model is validated by numerical simulations and bubble condensation experiments from references, and good agreements are achieved. The bubble departure diameter at the orifice and the flow condensation length in the liquid channel are predicted by the model, and effects of various influencing parameters on bubble behaviors are analyzed. Prediction results indicate that the orifice diameter, the gas feeding rate, and the liquid velocity are the primary influence factors on the bubble departure diameter. The interfacial heat transfer as well as the bubble departure diameter has a direct impact on the bubble flow condensation length, which increases by 2.5 times over a system pressure range of 0.1 0.4 MPa, and decreases by 85% over a liquid subcooling range of 5 30 K. This work could be beneficial to the prediction of bubble formation and flow condensation processes and the design of cryogenic transfer pipes.

GASFLOW: A Computational Fluid Dynamics Code for Gases, Aerosols, and Combustion, Volume 3: Assessment Manual

DOE Office of Scientific and Technical Information (OSTI.GOV)

Müller, C.; Hughes, E. D.; Niederauer, G. F.

1998-10-01

Los Alamos National Laboratory (LANL) and Forschungszentrum Karlsruhe (FzK) are developing GASFLOW, a three-dimensional (3D) fluid dynamics field code as a best- estimate tool to characterize local phenomena within a flow field. Examples of 3D phenomena include circulation patterns; flow stratification; hydrogen distribution mixing and stratification; combustion and flame propagation; effects of noncondensable gas distribution on local condensation and evaporation; and aerosol entrainment, transport, and deposition. An analysis with GASFLOW will result in a prediction of the gas composition and discrete particle distribution in space and time throughout the facility and the resulting pressure and temperature loadings on the wallsmore » and internal structures with or without combustion. A major application of GASFLOW is for predicting the transport, mixing, and combustion of hydrogen and other gases in nuclear reactor containment and other facilities. It has been applied to situations involving transporting and distributing combustible gas mixtures. It has been used to study gas dynamic behavior in low-speed, buoyancy-driven flows, as well as sonic flows or diffusion dominated flows; and during chemically reacting flows, including deflagrations. The effects of controlling such mixtures by safety systems can be analyzed. The code version described in this manual is designated GASFLOW 2.1, which combines previous versions of the United States Nuclear Regulatory Commission code HMS (for Hydrogen Mixing Studies) and the Department of Energy and FzK versions of GASFLOW. The code was written in standard Fortran 90. This manual comprises three volumes. Volume I describes the governing physical equations and computational model. Volume II describes how to use the code to set up a model geometry, specify gas species and material properties, define initial and boundary conditions, and specify different outputs, especially graphical displays. Sample problems are included. Volume III contains some of the assessments performed by LANL and FzK« less

121. FRONT ELEVATION OF TELLURIDE IRON WORKS 2.5 BY 4FOOT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

121. FRONT ELEVATION OF TELLURIDE IRON WORKS 2.5 BY 4-FOOT RETORT, USED TO FLASH MERCURY FROM GOLD. MERCURY VAPOR THEN CONDENSED ON INSIDE OF HOOD AND WAS COLLECTED FOR REUSE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

Kinetics on cocondensation of phenol and urea

Treesearch

Bunichiro Tomita; Yasunori Yoshida; Chung-Yun. Hse

1993-01-01

The chemical kinetics on cocondensation between methylolphenols and urea under acidic condition were investigated using 2- and 4-hydroxybenzyl alcohols as well as 2,4,6-trimethylolphenol as model compounds. The reactivity of the cocondensation were compared between o- and p-methylol groups. Moreover, the kinetics on self-condensations of monomethylolphenols and...

Molecular dynamics simulation of Bu4N+ in dimethylformamide: Solvation-induced volume changes

NASA Astrophysics Data System (ADS)

Kiselev, M. G.; Safonova, L. P.

2011-06-01

The structure of the Bu4N+-dimethylformamide system in the condensed and gas phases was studied by molecular dynamics simulation and quantum-chemical calculations. The calculation results were used to reveal the role played by steric effects in the volumetric characteristics of ion solvation.

EFFECT OF PH ON THE REACTION OF 2,4-DINITROPHENYLHYDRAZINE WITH FORMALDEHYDE AND ACETALDEHYDE

EPA Science Inventory

The acid-catalyzed condensation reaction of a molecule of 2,4-dinitrophenyl-hydrazine (DNPH) with a carbonyl compound is a well known reaction for characterizing aldehydes and ketones. The DNPH derivatives are used to identify qualitatively the parent carbonyl compound by melting...

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy

PubMed Central

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B.; Parodi, Katia; Jia, Xun

2017-01-01

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV/u. Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e., carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case 3 × 107 carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10%) isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the beam energy and voxel size, the computation time to simulate 107 carbons was 9.9–125 sec, 2.5–50 sec and 60–612 sec on an AMD Radeon GPU card, an NVidia GeForce GTX 1080 GPU card and an Intel Xeon E5-2640 CPU, respectively. The combined accuracy, efficiency and portability make goCMC attractive for research and clinical applications in carbon ion therapy. PMID:28140352

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy

NASA Astrophysics Data System (ADS)

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B.; Parodi, Katia; Jia, Xun

2017-05-01

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV u-1. Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e. carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case 3× {{10}7} carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10% isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the beam energy and voxel size, the computation time to simulate {{10}7} carbons was 9.9-125 s, 2.5-50 s and 60-612 s on an AMD Radeon GPU card, an NVidia GeForce GTX 1080 GPU card and an Intel Xeon E5-2640 CPU, respectively. The combined accuracy, efficiency and portability make goCMC attractive for research and clinical applications in carbon ion therapy.

Initial development of goCMC: a GPU-oriented fast cross-platform Monte Carlo engine for carbon ion therapy.

PubMed

Qin, Nan; Pinto, Marco; Tian, Zhen; Dedes, Georgios; Pompos, Arnold; Jiang, Steve B; Parodi, Katia; Jia, Xun

2017-05-07

Monte Carlo (MC) simulation is considered as the most accurate method for calculation of absorbed dose and fundamental physics quantities related to biological effects in carbon ion therapy. To improve its computational efficiency, we have developed a GPU-oriented fast MC package named goCMC, for carbon therapy. goCMC simulates particle transport in voxelized geometry with kinetic energy up to 450 MeV u -1 . Class II condensed history simulation scheme with a continuous slowing down approximation was employed. Energy straggling and multiple scattering were modeled. δ-electrons were terminated with their energy locally deposited. Four types of nuclear interactions were implemented in goCMC, i.e. carbon-hydrogen, carbon-carbon, carbon-oxygen and carbon-calcium inelastic collisions. Total cross section data from Geant4 were used. Secondary particles produced in these interactions were sampled according to particle yield with energy and directional distribution data derived from Geant4 simulation results. Secondary charged particles were transported following the condensed history scheme, whereas secondary neutral particles were ignored. goCMC was developed under OpenCL framework and is executable on different platforms, e.g. GPU and multi-core CPU. We have validated goCMC with Geant4 in cases with different beam energy and phantoms including four homogeneous phantoms, one heterogeneous half-slab phantom, and one patient case. For each case [Formula: see text] carbon ions were simulated, such that in the region with dose greater than 10% of maximum dose, the mean relative statistical uncertainty was less than 1%. Good agreements for dose distributions and range estimations between goCMC and Geant4 were observed. 3D gamma passing rates with 1%/1 mm criterion were over 90% within 10% isodose line except in two extreme cases, and those with 2%/1 mm criterion were all over 96%. Efficiency and code portability were tested with different GPUs and CPUs. Depending on the beam energy and voxel size, the computation time to simulate [Formula: see text] carbons was 9.9-125 s, 2.5-50 s and 60-612 s on an AMD Radeon GPU card, an NVidia GeForce GTX 1080 GPU card and an Intel Xeon E5-2640 CPU, respectively. The combined accuracy, efficiency and portability make goCMC attractive for research and clinical applications in carbon ion therapy.

Effect of magnetic field inhomogeneity on ion cyclotron motion coherence at high magnetic field.

PubMed

Vladimirov, Gleb; Kostyukevich, Yury; Hendrickson, Christopher L; Blakney, Greg T; Nikolaev, Eugene

2015-01-01

A three-dimensional code based on the particle-in-cell algorithm modified to account for the inhomogeneity of the magnetic field was applied to determine the effect of Z(1), Z(2), Z(3), Z(4), X, Y, ZX, ZY, XZ(2) YZ(2), XY and X(2)-Y(2) components of an orthogonal magnetic field expansion on ion motion during detection in an FT-ICR cell. Simulations were performed for magnetic field strengths of 4.7, 7, 14.5 and 21 Tesla, including experimentally determined magnetic field spatial distributions for existing 4.7 T and 14.5 T magnets. The effect of magnetic field inhomogeneity on ion cloud stabilization ("ion condensation") at high numbers of ions was investigated by direct simulations of individual ion trajectories. Z(1), Z(2), Z(3) and Z(4) components have the largest effect (especially Z(1)) on ion cloud stability. Higher magnetic field strength and lower m/z demand higher relative magnetic field homogeneity to maintain cloud coherence for a fixed time period. The dependence of mass resolving power upper limit on Z(1) inhomogeneity is evaluated for different magnetic fields and m/z. The results serve to set the homogeneity requirements for various orthogonal magnetic field components (shims) for future FT-ICR magnet design.

NASA Tech Briefs, January 2004

NASA Technical Reports Server (NTRS)

2004-01-01

Topics covered include: Multisensor Instrument for Real-Time Biological Monitoring; Sensor for Monitoring Nanodevice-Fabrication Plasmas; Backed Bending Actuator; Compact Optoelectronic Compass; Micro Sun Sensor for Spacecraft; Passive IFF: Autonomous Nonintrusive Rapid Identification of Friendly Assets; Finned-Ladder Slow-Wave Circuit for a TWT; Directional Radio-Frequency Identification Tag Reader; Integrated Solar-Energy-Harvesting and -Storage Device; Event-Driven Random-Access-Windowing CCD Imaging System; Stroboscope Controller for Imaging Helicopter Rotors; Software for Checking State-charts; Program Predicts Broadband Noise from a Turbofan Engine; Protocol for a Delay-Tolerant Data-Communication Network; Software Implements a Space-Mission File-Transfer Protocol; Making Carbon-Nanotube Arrays Using Block Copolymers: Part 2; Modular Rake of Pitot Probes; Preloading To Accelerate Slow-Crack-Growth Testing; Miniature Blimps for Surveillance and Collection of Samples; Hybrid Automotive Engine Using Ethanol-Burning Miller Cycle; Fabricating Blazed Diffraction Gratings by X-Ray Lithography; Freeze-Tolerant Condensers; The StarLight Space Interferometer; Champagne Heat Pump; Controllable Sonar Lenses and Prisms Based on ERFs; Measuring Gravitation Using Polarization Spectroscopy; Serial-Turbo-Trellis-Coded Modulation with Rate-1 Inner Code; Enhanced Software for Scheduling Space-Shuttle Processing; Bayesian-Augmented Identification of Stars in a Narrow View; Spacecraft Orbits for Earth/Mars-Lander Radio Relay; and Self-Inflatable/Self-Rigidizable Reflectarray Antenna.

Influence of iron and copper oxides on polychlorinated diphenyl ether formation in heterogeneous reactions.

PubMed

Liu, Wenxia; Shen, Lianfeng; Zhang, Fawen; Liu, Wenbin; Zheng, Minghui; Yang, Xitian

2013-08-01

Polychlorinated diphenyl ether (PCDE) has attracted great attention recently as an important type of environmental pollutant. The influence of iron and copper oxides on formation of PCDEs was investigated using laboratory-scale flow reactors under air and under nitrogen at 350 °C, a temperature corresponding to the post-combustion zone of a municipal solid waste incinerator. The results show that the 2,2',3,4,4',5,5',6-otachlorodiphenyl ether (OCDE) formed from the condensation of pentachlorophenol (PCP) and 1,2,4,5-tetrachlorobenzene (Cl4Bz) is the predominant congener formed on the SiO2/Fe2O3 surface with and without oxygen. This indicated that HCl elimination between PCP and 1,2,4,5-Cl4Bz molecules formed 2,2',3,4,4',5,5',6-OCDE in the presence of Fe2O3. On the other hand, decachlorodiphenyl ether, nonachlorodiphenyl ether, and OCDE were the dominant products on the SiO2/CuO surface without oxygen, although the 2,2',3,4,4',5,5',6-OCDE was the dominant product on the SiO2/CuO surface with oxygen. Therefore, the presence of Fe2O3 and CuO influences the formation and homologue distribution of PCDEs, which shifted towards the lower chlorinated species. Fe2O3 can promote both the condensation and dechlorination reaction without oxygen. On the contrary, with oxygen, Fe2O3 suppresses the condensation of chlorobenzene and chlorophenol to form PCDEs and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs). CuO can increase the formation of lower chlorinated PCDEs and PCDDs without oxygen. In conclusion, the different fly ash components have a major influence on PCDE emissions.

Stimulated Desorption from Icy Aerosol Particles: A Possible Relevance To Titan's Ionospheric Conditions

NASA Astrophysics Data System (ADS)

Bordalo, Vinicius; Mejia, Christian; da Silveira, Enio F.; Seperuelo Duarte, Eduardo; Pilling, Sergio

Saturn's largest moon, Titan, has a dense atmosphere primarily composed of molecular nitro-gen (N2 , 96%) and methane (CH4 , 4%). Its atmospheric structure has been intensively studied recently due to the large amount of data obtained in situ by the Huygens probe during its de-cent to the surface on 14 January 2005. The probe could diagnose the composition of the haze particles made up organic chains containing H, C and N. Hydrocarbons and nitriles produced by photolysis of CH4 at high altitudes (˜ 2,000 km) act as embryos of aerosols of Titan as they fall to the surface. It is expected that CH4 condenses on these particles forming a layer of ice by adsorption or nucleation. Due to the high abundance of these aerosols throughout the atmo-sphere of Titan, their presence are relevant for the ionic balance of the atmosphere, especially the lower ionosphere promoted mainly by the flux of galactic cosmic rays (GCR). We have investigated the production of ions by electronic sputtering process due to the bombardment of the surfaces of aerosols by heavy ions. Time-of-flight (TOF) technique was used to obtain ion sputtering yields. An ice layer of CH4 was grown by condensation over a pre-condensed N2 ice in high vacuum chamber (1 × 10-7 mbar) at cryogenic temperature (10 K). Relative sputtering yields due to fast projectiles (252 Cf fission fragment ˜ 65 MeV) on the ice surfaces were measured. The bombardment was continued during the successive growth of both con-densed layers; the negative and positive sputtered ions were identified by TOF. Hybrid species including NH+ (17 u), HCN+ (27 u) and CN- (26 u) were formed, as well as the acetonitrile 3 ion (CH3 CN+ , 41 u). We argue that a similar process of continued ion replenishment into the gas phase by sputtering in aerosols ubiquitous in the lower ionosphere of Titan may occur and should be further investigated.

Silurian shale origin for light oil, condensate, and gas in Algeria and the Middle East

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zumberge, J.E.; Macko, S.

1996-01-01

Two of the largest gas fields in the world, Hasi R'Mel, Algeria and North Dome, Qatar, also contain substantial condensate and light oil reserves. Gas to source rock geochemical correlation is difficult due to the paucity of molecular parameters in the former although stable isotope composition is invaluable. However, by correlating source rocks with light oils and condensates associated with gas production using traditional geochemical parameters such as biomarkers and isotopes, a better understanding of the origin of the gas is achieved. Much of the crude oil in the Ghadames/Illizi Basins of Algeria has long been thought to have beenmore » generated from Silurian shales. New light oil discoveries in Saudi Arabia have also been shown to originate in basal euxinic Silurian shales. Key sterane and terpane biomarkers as well as the stable carbon isotopic compositions of the C15+ saturate and aromatic hydrocarbon fractions allow for the typing of Silurian-sourced, thermally mature light oils in Algeria and the Middle East. Even though biomarkers are often absent due to advanced thermal maturity, condensates can be correlated to the light oils using (1) carbon isotopes of the residual heavy hydrocarbon fractions, (2) light hydrocarbon distributions (e.g., C7 composition), and (3) compound specific carbon isotopic composition of the light hydrocarbons. The carbon isotopes of the C2-C4 gas components ran then be compared to the associated condensate and light oil isotopic composition.« less

Silurian shale origin for light oil, condensate, and gas in Algeria and the Middle East

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zumberge, J.E.; Macko, S.

Two of the largest gas fields in the world, Hasi R`Mel, Algeria and North Dome, Qatar, also contain substantial condensate and light oil reserves. Gas to source rock geochemical correlation is difficult due to the paucity of molecular parameters in the former although stable isotope composition is invaluable. However, by correlating source rocks with light oils and condensates associated with gas production using traditional geochemical parameters such as biomarkers and isotopes, a better understanding of the origin of the gas is achieved. Much of the crude oil in the Ghadames/Illizi Basins of Algeria has long been thought to have beenmore » generated from Silurian shales. New light oil discoveries in Saudi Arabia have also been shown to originate in basal euxinic Silurian shales. Key sterane and terpane biomarkers as well as the stable carbon isotopic compositions of the C15+ saturate and aromatic hydrocarbon fractions allow for the typing of Silurian-sourced, thermally mature light oils in Algeria and the Middle East. Even though biomarkers are often absent due to advanced thermal maturity, condensates can be correlated to the light oils using (1) carbon isotopes of the residual heavy hydrocarbon fractions, (2) light hydrocarbon distributions (e.g., C7 composition), and (3) compound specific carbon isotopic composition of the light hydrocarbons. The carbon isotopes of the C2-C4 gas components ran then be compared to the associated condensate and light oil isotopic composition.« less

Waterless Condensers for the Teaching Laboratory: An Adaptation of Traditional Glassware

ERIC Educational Resources Information Center

Baum, Erich W.; Esteb, John J.; Wilson, Anne M.

2014-01-01

A simple adaptation of traditional "chemistry kit" condensers for the organic chemistry teaching laboratory is described. These waterless condensers have been employed safely with most solvents. They can be easily fabricated, stored, and used in the same manner as water-cooled condensers. These condensers were utilized in several…

A very large dew and rain ridge collector in the Kutch area (Gujarat, India)

NASA Astrophysics Data System (ADS)

Sharan, G.; Clus, O.; Singh, S.; Muselli, M.; Beysens, D.

2011-07-01

SummaryThe world's largest dew and rain collecting system, comprised of ridge-and-trough modules, was constructed in March 2006 at Panandhro in the semi-arid area of Kutch (NW India). The main goals were (i) to collect dew on a scale that could be beneficial to the local population (ii) to determine the efficiency of this new module shape, (iii) to determine whether results obtained from small measurement condensers can be projected to large condensers, (iv) to apply a computational fluid dynamic simulation to improve the condenser set-up. Preliminary studies performed with four standard plane condensers of 1 m 2 surface area, inclined 30° from horizontal, identified Panandhro as a promising site. The cumulated dew water during 192 days was 12.6 mm with a maximum of 0.556 mm/night. A large dew condenser (850 m 2 net total surface) was designed with 10 ridge-and-trough modules. The ridges are trapezoidal, 33 m long, 0.5 m wide at the top, 2.2 m wide at the base and sloping 30° from horizontal. The depth of the troughs between the ridges is 0.5 m. A 2.5 cm thick polystyrene foam rests on the surface as insulation with a radiative foil on top (similar to that developed by OPUR, see www.opur.fr). Numerical simulations using the computational fluid dynamic software PHOENICS were performed. The most profitable orientation was with the condenser oriented back to the wind direction, a configuration that lowers the wind velocity near the foil due to the combination of free convection and wind recirculation flows. A comparison of water yields over one year of measurements between four 1 m 2 plane condensers and a 850 m 2 ridge condenser showed a 42% lower yield on the large condenser. The difference is attributed mainly to folds in the plastic foil allowing water to fill the central ridge, thus decreasing radiative cooling. The output for 2007 was 6545 L, corresponding to 7.7 mm/day on average. The largest event was 251.4 L/night (0.3 mm). Such a condenser can also collect rain (and, to a lesser extent, fog). Chemical and biological analyses showed that dew water, once filtered and bottled, could be used for drinking after a light treatment to increase the pH. The price of this water could be lowered to reach 30% (dew only) or even 3% (dew plus rain) of the market prize.

Chromosome aberrations in the blood lymphocytes of astronauts after space flight

NASA Technical Reports Server (NTRS)

George, K.; Durante, M.; Wu, H.; Willingham, V.; Badhwar, G.; Cucinotta, F. A.

2001-01-01

Cytogenetic analysis of the lymphocytes of astronauts provides a direct measurement of space radiation damage in vivo, which takes into account individual radiosensitivity and considers the influence of microgravity and other stress conditions. Chromosome exchanges were measured in the blood lymphocytes of eight crew members after their respective space missions, using fluorescence in situ hybridization (FISH) with chromosome painting probes. Significant increases in aberrations were observed after the long-duration missions. The in vivo dose was derived from the frequencies of translocations and total exchanges using calibration curves determined before flight, and the RBE was estimated by comparison with individually measured physical absorbed doses. The values for average RBE were compared to the average quality factor (Q) from direct measurements of the lineal energy spectra using a tissue-equivalent proportional counter (TEPC) and radiation transport codes. The ratio of aberrations identified as complex was slightly higher after flight, which is thought to be an indication of exposure to high-LET radiation. To determine whether the frequency of complex aberrations measured in metaphase spreads after exposure to high-LET radiation was influenced by a cell cycle delay, chromosome damage was analyzed in prematurely condensed chromosome samples collected from two crew members before and after a short-duration mission. The frequency of complex exchanges after flight was higher in prematurely condensed chromosomes than in metaphase cells for one crew member.

Chromosome aberrations in the blood lymphocytes of astronauts after space flight.

PubMed

George, K; Durante, M; Wu, H; Willingham, V; Badhwar, G; Cucinotta, F A

2001-12-01

Cytogenetic analysis of the lymphocytes of astronauts provides a direct measurement of space radiation damage in vivo, which takes into account individual radiosensitivity and considers the influence of microgravity and other stress conditions. Chromosome exchanges were measured in the blood lymphocytes of eight crew members after their respective space missions, using fluorescence in situ hybridization (FISH) with chromosome painting probes. Significant increases in aberrations were observed after the long-duration missions. The in vivo dose was derived from the frequencies of translocations and total exchanges using calibration curves determined before flight, and the RBE was estimated by comparison with individually measured physical absorbed doses. The values for average RBE were compared to the average quality factor (Q) from direct measurements of the lineal energy spectra using a tissue-equivalent proportional counter (TEPC) and radiation transport codes. The ratio of aberrations identified as complex was slightly higher after flight, which is thought to be an indication of exposure to high-LET radiation. To determine whether the frequency of complex aberrations measured in metaphase spreads after exposure to high-LET radiation was influenced by a cell cycle delay, chromosome damage was analyzed in prematurely condensed chromosome samples collected from two crew members before and after a short-duration mission. The frequency of complex exchanges after flight was higher in prematurely condensed chromosomes than in metaphase cells for one crew member.

Shock tubes and waves; Proceedings of the Sixteenth International Symposium, Rheinisch-Westfaelische Technische Hochschule, Aachen, Federal Republic of Germany, July 26-31, 1987

NASA Astrophysics Data System (ADS)

Groenig, Hans

Topics discussed in this volume include shock wave structure, propagation, and interaction; shocks in condensed matter, dusty gases, and multiphase media; chemical processes and related combustion and detonation phenomena; shock wave reflection, diffraction, and focusing; computational fluid dynamic code development and shock wave application; blast and detonation waves; advanced shock tube technology and measuring technique; and shock wave applications. Papers are presented on dust explosions, the dynamics of shock waves in certain dense gases, studies of condensation kinetics behind incident shock waves, the autoignition mechanism of n-butane behind a reflected shock wave, and a numerical simulation of the focusing process of reflected shock waves. Attention is also given to the equilibrium shock tube flow of real gases, blast waves generated by planar detonations, modern diagnostic methods for high-speed flows, and interaction between induced waves and electric discharge in a very high repetition rate excimer laser.

Synthesis and Characterization of 1,4-Dihydro-3,1-Benzoxazines and 1,2,3,4-Tetrahydroquinazolines: An Unknown Structure Determination Experiment

ERIC Educational Resources Information Center

Bendorf, Holly D.; Vebrosky, Emily N.; Eck, Brian J.

2016-01-01

In this experiment for an upper-division course in organic structure determination, each student prepares an unknown compound and characterizes the product using multiple spectroscopic techniques. The unknowns, 2-aryl-substituted 1,4-dihydro-3,1-benzoxazines and 1,2,3,4-tetrahydroquinazolines, are prepared in a single step by the condensation of…

Validation of the WIMSD4M cross-section generation code with benchmark results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deen, J.R.; Woodruff, W.L.; Leal, L.E.

1995-01-01

The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment Research and Test Reactor (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code, WIMSD4M, very attractive, not only for the RERTR program, but also for the reactor physics community. The intent of the present paper is to validate the WIMSD4M cross-section librariesmore » for reactor modeling of fresh water moderated cores. The results of calculations performed with multigroup cross-section data generated with the WIMSD4M code will be compared against experimental results. These results correspond to calculations carried out with thermal reactor benchmarks of the Oak Ridge National Laboratory (ORNL) unreflected HEU critical spheres, the TRX LEU critical experiments, and calculations of a modified Los Alamos HEU D{sub 2}O moderated benchmark critical system. The benchmark calculations were performed with the discrete-ordinates transport code, TWODANT, using WIMSD4M cross-section data. Transport calculations using the XSDRNPM module of the SCALE code system are also included. In addition to transport calculations, diffusion calculations with the DIF3D code were also carried out, since the DIF3D code is used in the RERTR program for reactor analysis and design. For completeness, Monte Carlo results of calculations performed with the VIM and MCNP codes are also presented.« less

Retinoic acid influences anteroposterior positioning of epidermal sensory neurons and their gene expression in a developing chordate (amphioxus)

PubMed Central

Schubert, Michael; Holland, Nicholas D.; Escriva, Hector; Holland, Linda Z.; Laudet, Vincent

2004-01-01

In developing chordates, retinoic acid (RA) signaling patterns the rostrocaudal body axis globally and affects gene expression locally in some differentiating cell populations. Here we focus on development of epidermal sensory neurons in an invertebrate chordate (amphioxus) to determine how RA signaling influences their rostrocaudal distribution and gene expression (for AmphiCoe, a neural precursor gene; for amphioxus islet and AmphiERR, two neural differentiation genes; and for AmphiHox1, -3, -4, and -6). Treatments with RA or an RA antagonist (BMS009) shift the distribution of developing epidermal neurons anteriorly or posteriorly, respectively. These treatments also affect gene expression patterns in the epidermal neurons, suggesting that RA levels may influence specification of neuronal subtypes. Although colinear expression of Hox genes is well known for the amphioxus central nervous system, we find an unexpected comparable colinearity for AmphiHox1, -3, -4, and -6 in the developing epidermis; moreover, RA levels affect the anteroposterior extent of these Hox expression domains, suggesting that RA signaling controls a colinear Hox code for anteroposterior patterning of the amphioxus epidermis. Thus, in amphioxus, the developing peripheral nervous system appears to be structured by mechanisms parallel to those that structure the central nervous system. One can speculate that, during evolution, an ancestral deuterostome that structured its panepidermal nervous system with an RA-influenced Hox code gave rise to chordates in which this patterning mechanism persisted within the epidermal elements of the peripheral nervous system and was transferred to the neuroectoderm as the central nervous system condensed dorsally. PMID:15226493

Free-field Calibration of the Pressure Sensitivity of Microphones at Frequencies up to 80 kHz

NASA Technical Reports Server (NTRS)

Herring, G. C.; Zuckerwar, Allan J.; Elbing, Brian R.

2006-01-01

A free-field (FF) substitution method for calibrating the pressure sensitivity of microphones at frequencies up to 80 kHz is demonstrated with both grazing and normal incidence geometries. The substitution-based method, as opposed to a simultaneous method, avoids problems associated with the non-uniformity of the sound field and, as applied here, uses a 1/2 -inch air-condenser pressure microphone as a known reference. Best results were obtained with a centrifugal fan, which is used as a random, broadband sound source. A broadband source minimizes reflection-related interferences that often plague FF measurements. Calibrations were performed on 1/4-inch FF air-condenser, electret, and micro-electromechanical systems (MEMS) microphones in an anechoic chamber. The accuracy of this FF method is estimated by comparing the pressure sensitivity of an air-condenser microphone, as derived from the FF measurement, with that of an electrostatic actuator calibration and is typically 0.3 dB (95% confidence), over the range 2-80 kHz.

Measuring Humidity in the Charters of Freedom Encasements Using a Moisture Condensation Method

NASA Technical Reports Server (NTRS)

Burkett, Cecil G.; West, James W.; Levine, Joel S.

2004-01-01

The relative humidity of the atmosphere in the encasements containing the U.S. Constitution Pages 1 and 4, the Declaration of Independence, and the Bill of Rights was measured to be in the range of 55% to 61%. This value is significantly higher than the presumed relative humidity between 25 to 35 %, but is consistent with the measured samples extracted from Pages 2 and 3 of the U.S. Constitution. The cooling/condensation measurement technique used at NARA on July 23, 2001, and described in this paper to measure the water vapor content of the atmosphere in the hermetically sealed encasements containing the U. S. Constitution, the Declaration of Independence, and the Bill of Rights, proved to be a powerful new measurement technique. The cooling/condensation technique developed at NASA LaRC and utilized at NARA has important applications in the non-invasive measurement of relative humidity in the atmospheres of sealed encasements and could become a standard measurement technique in this type of analysis.

Thermogravimetric and kinetic study of Pinyon pine in the various gases.

PubMed

Kim, Seung-Soo; Shenoy, Alok; Agblevor, Foster A

2014-03-01

As a renewable resource, Pinyon pine can be converted into bio-oil, gas, and char through pyrolysis. It is known that recycling of the non-condensable gases, which are produced by fast pyrolysis, can increase liquid yield and decrease char yield. In this study, pyrolysis characteristics and kinetics of Pinyon pine were investigated in TGA using simulated non-condensable gases (N2, H2/N2, H2/CO2, and He/CO/H2). The apparent activation energy of Pinyon pine increased from 43.9 to 160.3kJ mol(-1) with increasing pyrolysis conversion from 5% to 95% in pure nitrogen, and reaction order was 1.35. When hydrogen (H2) and carbon monoxide (CO) mixtures were used as simulated gases, the maximum degradation temperature and activation energy decreased by 4-11°C and 6.1-10.2kJ/mol, respectively. The results show that recycling of non-condensable gases could positively influence the fast pyrolysis of biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

Continuous condensation in nanogrooves

NASA Astrophysics Data System (ADS)

Malijevský, Alexandr

2018-05-01

We consider condensation in a capillary groove of width L and depth D , formed by walls that are completely wet (contact angle θ =0 ), which is in a contact with a gas reservoir of the chemical potential μ . On a mesoscopic level, the condensation process can be described in terms of the midpoint height ℓ of a meniscus formed at the liquid-gas interface. For macroscopically deep grooves (D →∞ ), and in the presence of long-range (dispersion) forces, the condensation corresponds to a second-order phase transition, such that ℓ ˜(μcc-μ ) -1 /4 as μ →μcc - where μc c is the chemical potential pertinent to capillary condensation in a slit pore of width L . For finite values of D , the transition becomes rounded and the groove becomes filled with liquid at a chemical potential higher than μc c with a difference of the order of D-3. For sufficiently deep grooves, the meniscus growth initially follows the power law ℓ ˜(μcc-μ ) -1 /4 , but this behavior eventually crosses over to ℓ ˜D -(μ-μc c) -1 /3 above μc c, with a gap between the two regimes shown to be δ ¯μ ˜D-3 . Right at μ =μc c , when the groove is only partially filled with liquid, the height of the meniscus scales as ℓ*˜(D3L) 1 /4 . Moreover, the chemical potential (or pressure) at which the groove is half-filled with liquid exhibits a nonmonotonic dependence on D with a maximum at D ≈3 L /2 and coincides with μc c when L ≈D . Finally, we show that condensation in finite grooves can be mapped on the condensation in capillary slits formed by two asymmetric (competing) walls a distance D apart with potential strengths depending on L . All these predictions, based on mesoscopic arguments, are confirmed by fully microscopic Rosenfeld's density functional theory with a reasonable agreement down to surprisingly small values of both L and D .

Heat Transfer Enhancement During Water and Hydrocarbon Condensation on Lubricant Infused Surfaces.

PubMed

Preston, Daniel J; Lu, Zhengmao; Song, Youngsup; Zhao, Yajing; Wilke, Kyle L; Antao, Dion S; Louis, Marcel; Wang, Evelyn N

2018-01-11

Vapor condensation is routinely used as an effective means of transferring heat or separating fluids. Dropwise condensation, where discrete droplets form on the condenser surface, offers a potential improvement in heat transfer of up to an order of magnitude compared to filmwise condensation, where a liquid film covers the surface. Low surface tension fluid condensates such as hydrocarbons pose a unique challenge since typical hydrophobic condenser coatings used to promote dropwise condensation of water often do not repel fluids with lower surface tensions. Recent work has shown that lubricant infused surfaces (LIS) can promote droplet formation of hydrocarbons. In this work, we confirm the effectiveness of LIS in promoting dropwise condensation by providing experimental measurements of heat transfer performance during hydrocarbon condensation on a LIS, which enhances heat transfer by ≈450% compared to an uncoated surface. We also explored improvement through removal of noncondensable gases and highlighted a failure mechanism whereby shedding droplets depleted the lubricant over time. Enhanced condensation heat transfer for low surface tension fluids on LIS presents the opportunity for significant energy savings in natural gas processing as well as improvements in thermal management, heating and cooling, and power generation.

Circumstellar dust in symbiotic novae

NASA Astrophysics Data System (ADS)

Jurkic, Tomislav; Kotnik-Karuza, Dubravka

2015-08-01

Physical properties of the circumstellar dust and associated physical mechanisms play an important role in understanding evolution of symbiotic binaries. We present a model of inner dust regions around the cool Mira component of the two symbiotic novae, RR Tel and HM Sge, based on the long-term near-IR photometry, infrared ISO spectra and mid-IR interferometry. Pulsation properties and long-term variabilities were found from the near-IR light curves. The dust properties were determined using the DUSTY code which solves the radiative transfer. No changes in pulsational parameters were found, but a long-term variations with periods of 20-25 years have been detected which cannot be attributed to orbital motion.Circumstellar silicate dust shell with inner dust shell temperatures between 900 K and 1300 K and of moderate optical depth can explain all the observations. RR Tel showed the presence of an optically thin CS dust envelope and an optically thick dust region outside the line of sight, which was further supported by the detailed modelling using the 2D LELUYA code. Obscuration events in RR Tel were explained by an increase in optical depth caused by the newly condensed dust leading to the formation of a compact dust shell. HM Sge showed permanent obscuration and a presence of a compact dust shell with a variable optical depth. Scattering of the near-IR colours can be understood by a change in sublimation temperature caused by the Mira variability. Presence of large dust grains (up to 4 µm) suggests an increased grain growth in conditions of increased mass loss. The mass loss rates of up to 17·10-6 MSun/yr were significantly higher than in intermediate-period single Miras and in agreement with longer-period O-rich AGB stars.Despite the nova outburst, HM Sge remained enshrouded in dust with no significant dust destruction. The existence of unperturbed dust shell suggests a small influence of the hot component and strong dust shielding from the UV flux. By the use of the CLOUDY code, we have showed that a high-density gas region can effectively stop most of the UV flux from the white dwarf and provide the observed dust shielding.

Enhanced condensation heat transfer with wettability patterning

NASA Astrophysics Data System (ADS)

Sinha Mahapatra, Pallab; Ghosh, Aritra; Ganguly, Ranjan; Megaridis, Constantine

2015-11-01

Condensation of water vapor on metal surfaces is useful for many engineering applications. A facile and scalable method is proposed for removing condensate from a vertical plate during dropwise condensation (DWC) in the presence of non-condensable gases (NCG). We use wettability-patterned superhydrophilic tracks (filmwise condensing domains) on a mirror-finish (hydrophilic) aluminum surface that promotes DWC. Tapered, horizontal ``collection'' tracks are laid to create a Laplace pressure driven flow, which collects condensate from the mirror-finish domains and sends it to vertical ``drainage tracks'' for gravity-induced shedding. An optimal design is achieved by changing the fractional area of superhydrophilic tracks with respect to the overall plate surface, and augmenting capillary-driven condensate-drainage by adjusting the track spatial layout. The design facilitates pump-less condensate drainage and enhances DWC heat transfer on the mirror-finish regions. The study highlights the relative influences of the promoting and retarding effects of dropwise and filmwise condensation zones on the overall heat transfer improvement on the substrate. The study demonstrated ~ 34% heat transfer improvement on Aluminum surface for the optimized design.

Turbo Trellis Coded Modulation With Iterative Decoding for Mobile Satellite Communications

NASA Technical Reports Server (NTRS)

Divsalar, D.; Pollara, F.

1997-01-01

In this paper, analytical bounds on the performance of parallel concatenation of two codes, known as turbo codes, and serial concatenation of two codes over fading channels are obtained. Based on this analysis, design criteria for the selection of component trellis codes for MPSK modulation, and a suitable bit-by-bit iterative decoding structure are proposed. Examples are given for throughput of 2 bits/sec/Hz with 8PSK modulation. The parallel concatenation example uses two rate 4/5 8-state convolutional codes with two interleavers. The convolutional codes' outputs are then mapped to two 8PSK modulations. The serial concatenated code example uses an 8-state outer code with rate 4/5 and a 4-state inner trellis code with 5 inputs and 2 x 8PSK outputs per trellis branch. Based on the above mentioned design criteria for fading channels, a method to obtain he structure of the trellis code with maximum diversity is proposed. Simulation results are given for AWGN and an independent Rayleigh fading channel with perfect Channel State Information (CSI).

SYNTHESIS AND BIOLOGICAL EVALUATION OF N-(SUBSTITUTED PHENYL)-2-(5H-[1,2,4]TRIAZINO[5,6-b]INDOL-3-YLSULFANYL)ACETAMIDES AS ANTIMICROBIAL, ANTIDEPRESSANT AND ANTICONVULSANT AGENTS.

PubMed

Shruthi, N; Poojary, Boja; Kumar, Vasantha; Prathibha, A; Hussain, Mumtaz Mohammed; Revanasiddappa, B C; Joshi, Himanshu

2015-01-01

A new series of N-Aryl-2-(5H-[1,2,4]triazino[5,6-b]indol-3-ylsulfanyl)acetamides were synthesized by condensation of tricyclic compound 2,5-dihydro-3H-[1,2,4]triazino[5,6-b]indole-3-thione with chloro N-phenylacetamides. The tricyclic compound was obtained by condensation of Isatin with thiosemicarbazide. Chloro N-phenylacetamides were obtained from different substituted anilines. Their structures were characterized by IR, 1H NMR, LC-MS and elemental analyses. Newly synthesized compounds were screened for antimicrobial, antidepressant and anticonvulsant activities. Preliminary results indicated that most of the compounds showed lesser MIC value than the standard drug used when tested for antimicrobial activity. Some of the compounds were endowed with very good antidepressant and anticonvulsant activity.

Quantum error correcting codes and 4-dimensional arithmetic hyperbolic manifolds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guth, Larry, E-mail: lguth@math.mit.edu; Lubotzky, Alexander, E-mail: alex.lubotzky@mail.huji.ac.il

2014-08-15

Using 4-dimensional arithmetic hyperbolic manifolds, we construct some new homological quantum error correcting codes. They are low density parity check codes with linear rate and distance n{sup ε}. Their rate is evaluated via Euler characteristic arguments and their distance using Z{sub 2}-systolic geometry. This construction answers a question of Zémor [“On Cayley graphs, surface codes, and the limits of homological coding for quantum error correction,” in Proceedings of Second International Workshop on Coding and Cryptology (IWCC), Lecture Notes in Computer Science Vol. 5557 (2009), pp. 259–273], who asked whether homological codes with such parameters could exist at all.

Mathematical model of compact type evaporator

NASA Astrophysics Data System (ADS)

Borovička, Martin; Hyhlík, Tomáš

2018-06-01

In this paper, development of the mathematical model for evaporator used in heat pump circuits is covered, with focus on air dehumidification application. Main target of this ad-hoc numerical model is to simulate heat and mass transfer in evaporator for prescribed inlet conditions and different geometrical parameters. Simplified 2D mathematical model is developed in MATLAB SW. Solvers for multiple heat and mass transfer problems - plate surface temperature, condensate film temperature, local heat and mass transfer coefficients, refrigerant temperature distribution, humid air enthalpy change are included as subprocedures of this model. An automatic procedure of data transfer is developed in order to use results of MATLAB model in more complex simulation within commercial CFD code. In the end, Proper Orthogonal Decomposition (POD) method is introduced and implemented into MATLAB model.

Liquid phase evaporation on the normal shock wave in moist air transonic flows in nozzles

NASA Astrophysics Data System (ADS)

Dykas, Sławomir; Szymański, Artur; Majkut, Mirosław

2017-06-01

This paper presents a numerical analysis of the atmospheric air transonic flow through de Laval nozzles. By nature, atmospheric air always contains a certain amount of water vapor. The calculations were made using a Laval nozzle with a high expansion rate and a convergent-divergent (CD) "half-nozzle", referred to as a transonic diffuser, with a much slower expansion rate. The calculations were performed using an in-house CFD code. The computational model made it possible to simulate the formation of the liquid phase due to spontaneous condensation of water vapor contained in moist air. The transonic flow calculations also take account of the presence of a normal shock wave in the nozzle supersonic part to analyze the effect of the liquid phase evaporation.

Icephobicity and the effect of water condensation on the superhydrophobic low-density polyethylene surface

NASA Astrophysics Data System (ADS)

Yuan, Zhiqing; Wang, Menglei; Huang, Juan; Wang, Xian; Bin, Jiping; Peng, Chaoyi; Xing, Suli; Xiao, Jiayu; Zeng, Jingcheng; Xiao, Ximei; Fu, Xin; Gong, Huifang; Zhao, Dejian; Chen, Hong

2015-06-01

A superhydrophobic surface was obtained on a low-density polyethylene (LDPE) substrate using a facile method. The water contact angle and the sliding angle of the superhydrophobic LDPE surface were 155 ± 2° and 4°, respectively. The ice shear stress of the superhydrophobic LDPE surface was 2.08 times smaller than that of the flat LDPE surface. The superhydrophobic surface still showed excellent icephobicity and superhydrophobicity after undergoing a circulatory icing/deicing procedure five times. In addition, water condensation and its effect on the icephobicity of the as-prepared superhydrophobic surface were also studied.

A Simple Organic Microscale Experiment Illustrating the Equilibrium Aspect of the Aldol Condensation

NASA Astrophysics Data System (ADS)

Harrison, Ernest A., Jr.

1998-05-01

A simple microscale experiment has been developed that illustrates the equilibrium aspect of the aldol condensation by using two versions of the standard preparation of tetraphenylcyclopentadienone (5) from benzil (1) and 1,3-diphenyl-2-propanone (2). In version (high base concentration) a mixture of 5 and the diastereomeric 4-hydroxy-2,3,4,5-tetraphenyl-2-cyclopenten-1-ones 3 and 4 are produced, while in the other (low base concentration) a mixture of 1, 2, 3, and 4 results. The experiment is typically carried out in conjunction with the previously reported preparation/dehydration of 3, thus the students provide themselves with authentic samples of 3 and 5. Using these, plus authentic samples of 1 and 2 which are made available, students are able to identify all of the components in the equilibrium mixtures, except 4, by TLC analysis. In the case of 4, students are expected to propose a reasonable structure for this compound based on the observed chemistry and the spectroscopic evidence which is provided (i.e., NMR, IR and mass spectra). The experiment lends itself nicely to either the traditional or problem-solving approach, and it also opens up opportunities for collaborative learning.

Turboexpanders aid condensate recovery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Houghton, J.; McLay, J.D.

1973-03-05

Turboexpander plants built by Fluor are operating in 18 locations throughout the world, with the first one having been built in 1963. These plants, plus those under construction, account for a combined gas capacity or more than 4,000 MMscfd. In both gas-processing and cryogenic operations, the turboexpander is gaining wide acceptance in such areas as North and South America, the Middle East, and N. Africa. In a typical plant, feed gas is first dehydrated before being chilled by heat exchange with the gas product from the turboexpander. Condensate liquids are separated from the gas stream which is then expanded. Furthermore » condensed liquids resulting from the expansion-cooling effect are separated for fractionation. The degree of expansion can be varied to recover up to 60 to 90% of the ethane contained in the feed gas. The most efficient use of turboexpander refrigeration is dependent upon the product required.« less

Condensed bridgehead nitrogen heterocyclic system: synthesis and pharmacological activities of 1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazole derivatives of ibuprofen and biphenyl-4-yloxy acetic acid.

PubMed

Amir, Mohd; Kumar, Harish; Javed, S A

2008-10-01

Several 3,6-disubstituted-1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles were prepared by condensation of 4-amino-5-substituted-3-mercapto-(4H)-1,2,4-triazoles (3a,b) with various substituted aromatic acids and aryl/alkyl isothiocyanates through a one-pot reaction. These compounds were investigated for their anti-inflammatory, analgesic, ulcerogenic, lipid peroxidation, antibacterial and antifungal activities. Some of the synthesized compounds showed potent anti-inflammatory activity along with minimal ulcerogenic effect and lipid peroxidation, compared to those of ibuprofen and flurbiprofen. Some of the tested compounds also showed moderate antimicrobial activity against tested bacterial and fungal strains.

MELCOR/CONTAIN LMR Implementation Report. FY14 Progress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humphries, Larry L; Louie, David L.Y.

2014-10-01

This report describes the preliminary implementation of the sodium thermophysical properties and the design documentation for the sodium models of CONTAIN-LMR to be implemented into MELCOR 2.1. In the past year, the implementation included two separate sodium properties from two different sources. The first source is based on the previous work done by Idaho National Laboratory by modifying MELCOR to include liquid lithium equation of state as a working fluid to model the nuclear fusion safety research. To minimize the impact to MELCOR, the implementation of the fusion safety database (FSD) was done by utilizing the detection of the datamore » input file as a way to invoking the FSD. The FSD methodology has been adapted currently for this work, but it may subject modification as the project continues. The second source uses properties generated for the SIMMER code. Preliminary testing and results from this implementation of sodium properties are given. In this year, the design document for the CONTAIN-LMR sodium models, such as the two condensable option, sodium spray fire, and sodium pool fire is being developed. This design document is intended to serve as a guide for the MELCOR implementation. In addition, CONTAIN-LMR code used was based on the earlier version of CONTAIN code. Many physical models that were developed since this early version of CONTAIN may not be captured by the code. Although CONTAIN 2, which represents the latest development of CONTAIN, contains some sodium specific models, which are not complete, the utilizing CONTAIN 2 with all sodium models implemented from CONTAIN-LMR as a comparison code for MELCOR should be done. This implementation should be completed in early next year, while sodium models from CONTAIN-LMR are being integrated into MELCOR. For testing, CONTAIN decks have been developed for verification and validation use.« less

Isolation of friedelin from black condensate of cork.

PubMed

Pires, Ricardo A; Aroso, Ivo; Silva, Susana P; Mano, João F; Reis, Rui L

2011-11-01

Black condensates (BC) are wastes of the insulation corkboard industry that contain several valuable chemicals, including friedelin, a terpene exhibiting biological activity. Herein, we report a straightforward procedure to extract friedelin from BC. Using this procedure, we were able to extract friedelin with yields between 0.4% and 2.9% and to further purify it obtaining purities from 77.0% to 99.3% (HPLC). The initial BC (2 batches), extracted raw product and purified friedelin were analyzed using FTIR. The extraction yields and purities were found to be directly related to the intensity of the carbonyl vibration at 1713 cm(-1) in the FTIR spectrum of the used BC batch. Therefore, these spectra can be used to screen and select BC batches suitable for friedelin extraction.

Spread Spectrum Visual Sensor Network Resource Management Using an End-to-End Cross-Layer Design

DTIC Science & Technology

2011-02-01

Coding In this work, we use rate compatible punctured convolutional (RCPC) codes for channel coding [11]. Using RCPC codes al- lows us to utilize Viterbi’s...11] J. Hagenauer, “ Rate - compatible punctured convolutional codes (RCPC codes ) and their applications,” IEEE Trans. Commun., vol. 36, no. 4, pp. 389...source coding rate , a channel coding rate , and a power level to all nodes in the

GlC analysis of temperature effects on furfural production during pyrolysis of black cherry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnes D.P.; Blankenhorn, P.R.; Murphey, W.K.

1979-10-01

Thermal degradation of black cherry (Prunus serotina Ehrh.) was conducted in an inert atmosphere at temperatures ranging from 250 degrees to l000 degrees Celcius. The volatiles produced during carbonization were condensed in a liquid nitrogen trap and separated by steam distillation after which they were extracted with ether. This fraction was analyzed by gas-liquid chromatography (GLC) using a 4 mm (inside diameter) by 1.83 m long glass column packed with l0 percent methyl silicone fluid. The (GLC) column temperature was programed from 40 degrees to 240 degrees at a rate of l2.5 degrees Celcius per minute. Using this GLC temperaturemore » program, three chromatograms from each carbonization temperature were obtained and the furfural peak was identified and quantitatively analyzed. As carbonization temperature increased from 250 degrees at 500 degrees Celcius, the amount of furfural in the condensate also increased. The condensate chromatograms show that considerably more compounds are formed at temperatures above 320 degrees Celcius. The chromatograms from the temperature range of 500 degrees to l000 degrees showed little change in the number of compounds detected. Regression analysis revealed relationships between carbonization temperature, mass of the condensate, and mass furfural per original mass of wood.« less

A (72, 36; 15) box code

NASA Technical Reports Server (NTRS)

Solomon, G.

1993-01-01

A (72,36;15) box code is constructed as a 9 x 8 matrix whose columns add to form an extended BCH-Hamming (8,4;4) code and whose rows sum to odd or even parity. The newly constructed code, due to its matrix form, is easily decodable for all seven-error and many eight-error patterns. The code comes from a slight modification in the parity (eighth) dimension of the Reed-Solomon (8,4;5) code over GF(512). Error correction uses the row sum parity information to detect errors, which then become erasures in a Reed-Solomon correction algorithm.

AGOR 28

DTIC Science & Technology

2016-04-08

the JW pump on #4 twice due to small oil seal leaks on the pump shaft . Will continue to monitor. • Condensate Drains – Condensate from SCU’s, Fan...report to us. In addition, AF will be applied to the tail shafts as requested. The yard will then do a full coat of AF on the hull, including any

Modification of ruminal fermentation and methane production by adding legumes containing condensed tannins to an orchardgrass diet in continuous culture systems

USDA-ARS?s Scientific Manuscript database

Condensed tannins (CT) can alter ruminal fermentation and enteric methane (CH4) production in ruminants; however, research is lacking on how increased CT levels affect nutrient digestibility, volatile fatty acid (VFA) production, bacterial protein synthesis, fatty acid (FA) profiles, protozoal popul...

Effect of condensed tannin extract supplementation of performance, nitrogen, balance, gas emissions, and energetic losses of beef steers

USDA-ARS?s Scientific Manuscript database

Nitrogen emissions from concentrated animal feeding operations are of increasing concern to regulatory agencies and consumers. We evaluated the effect of top-dressing a finishing diet (14.4% crude protein) for beef steers with a commercially-available condensed tannin extract (CT) at three levels (0...

17 CFR 210.9-06 - Condensed financial information of registrant.

Code of Federal Regulations, 2010 CFR

2010-04-01

... EXCHANGE COMMISSION FORM AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF 1933... be presented in a note to the financial statements when the restricted net assets (§ 210.4-08(e)(3... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Condensed financial...

Condensed tannins: A proposed route to 2R,3R-(2,3-cis)-proanthocyanidins

Treesearch

Richard W. Hemingway; Peter E. Laks

1985-01-01

Roux,1 Haslam,2-4 and Stafford5-8 have proposed differing biogenetic schemes for the formation of proanthocyanidins (condensed tannins) in plants. All three schemes suffer from difficulties in explaining the formation of the 2R,3R-(2,3-cis)-proanthocyanidins that predominate in...

Accelerated cure of phenol-formaldehyde resins : studies with model compounds

Treesearch

Anthony H. Conner; Linda F. Lorenz; Kolby C. Hirth

2002-01-01

2-Hydroxymethylphenol (2-HMP) and 4-hydroxymethylphenol (4-HMP) were used as model compounds to study the reactions that occur during cure of phenol-formaldehyde (PF) resin to which cure accelerators (ethyl formate, propylene carbonate, g-butyrolactone, and triacetin) have been added. The addition of cure accelerators significantly increased the rate of condensation...

Cytogenetic toxicity effects of inorganic nickel and organic Ni(II) complexes on Brassica oleracea L. root meristem.

PubMed

Molas, J

2001-01-01

Experiments were carried out on the effect of nickel as an inorganic compound (NiSO4.7H2O) and organic Ni(II) complexes (i.e. Ni(II)-Glu and Ni(II)-EDTA) in concentrations of 20, 40 and 85 ?M dm-3 on meristematic cells of root tips of Brassica oleracea L. cv. Sława from Enkhouizen. All three tested chemical forms of nickel had a mitodepressive effect and inhibited root elongation. With respect to the degree of root elongation inhibition and mitodepressive effect, the tested forms of nickel can be put in the following order: Ni(II)-Glu NiSO4.7H2O Ni(II)-EDTA. In all three tested forms, nickel caused disturbances in mitotic divisions, resulting in anaphase bridges and binuclear cells, whose nuclei were joined by a bridge of condensed chromatin or separated. Inorganic nickel and Ni(II)-Glu in higher concentrations damaged nuclei (the amount of condensed chromatin increased), nucleoli (their structure became more condensed and vacuolisation was observed), endoplasmic reticulum (fragmentation, swelling of cisternae) and mitochondria (structure condensation).

Controllable synthesis of iron oxide nanoparticles in porous NaCl matrix

NASA Astrophysics Data System (ADS)

Kurapov, Yury A.; E Litvin, Stanislav; Romanenko, Sergey M.; Didikin, Gennadii G.; Oranskaya, Elena I.

2017-03-01

The paper gives the results of studying the structure of porous condensates of Fe + NaCl composition, chemical and phase compositions and dimensions of nanoparticles produced from the vapor phase by EB-PVD. Iron nanoparticles at fast removal from the vacuum oxidize in air and possess significant sorption capacity relative to oxygen and moisture. At heating in air, reduction of porous condensate weight occurs right to the temperature of 650 °C, primarily, due to desorption of physically sorbed moisture. Final oxidation of Fe3O4 to Fe2O3 proceeds in the range of 380 °C-650 °C, due to the remaining fraction of physically adsorbed oxygen. At iron concentrations of up to 10-15 at%, condensate sorption capacity is markedly increased with increase of iron concentration, i.e. of the quantity of fine particles. Increase of condensation temperature is accompanied by increase of nanoparticle size, resulting in a considerable reduction of the total area of nanoparticle surface, and, hence of their sorption capacity. In addition to condensation temperature, the size and phase composition of nanoparticles can also be controlled by heat treatment of initial condensate, produced at low condensation temperatures. Magnetite nanoparticles can be transferred into stable colloid systems.

Water vapour condensation in a partly closed structure. Comparison between results obtained with an inside wet or dry bottom wall

NASA Astrophysics Data System (ADS)

Batina, Jean; Peyrous, René

2018-04-01

We are interested in the determination of the more significant parameters acting on the water vapour condensation in a partly closed structure, submitted to external constraints (temperature and humidity), in view to recover the generated droplets as an additional source of potable water. External temperature variations, by inducing temperature differences between outside and inside of the structure, lead to convective movements and thermal variations inside this structure. Through an orifice, these movements permit a renewing of the humid inner air and can lead to the condensation of the water vapour initially contained in the inner air volume and/or on the walls. With the above hypotheses, and by using a numerical simulation [1] based on the ambient air characteristics and a finite volumes method, it appears that condensed water quantities are mainly depending on the boundary conditions imposed. These conditions are: 1) dimensions of the structure; 2) external temperature and relative hygrometry; 3) the phase φ (T/RH) linking thermal and hydrometric conditions; 4) the air renewing and its hygrometry for each phase; and 5) for each case, the fact that the inside bottom wall can be wet or dry. The resulting condensed water vapour quantities obtained, for the width section, point out clearly that they are very depending on this phase φ (T/RH) which appears as the more significant parameter and can be modified by the presence or not of a thin layer of water vapour on the inside bottom wall. Condensation phenomenon could be increased if φ could be optimized.

The Effect of Circumferential Tube Wall Heat Conduction upon Laminar Filmwise Condensation on the Outside of Condenser Tubes.

DTIC Science & Technology

1980-12-01

amount of tube surface area. Complications arise from these tubes, however, not the least being a sharp increase in the pumping power required to...V F. COMPARISON WITH PREVIOUS SOLUTIONS The aforementioned paper of Nicol, et al., [18] provided fertile ground for comparison, but only if the...000)-zz-jx’ - " C 4= LIUCW U )Lu L.U.QL&u.WWUI’ 40UJ. 0 C I (n .. Jte I- (�AJ~ ~ . LI. L I p~~~~~~~~~. 4. J.4.6~ i.~~ iui * ~ "W U~ - u . &LL.~ 4A

Electric field enhanced dropwise condensation on hydrophobic surfaces

NASA Astrophysics Data System (ADS)

Baratian, Davood; Hoek, Harmen; van den Ende, Dirk; Mugele, Frieder; Physics of Complex Fluids Team

2016-11-01

Dropwise condensation occurs when vapor condenses on a low surface energy surface, and the substrate is just partially wetted by the condensate. Dropwise condensation has attracted significant attention due to its reported superior heat transfer performance compared to filmwise condensation. Extensive research efforts are focused on how to promote, and enhance dropwise condensation by considering both physical and chemical factors. We have studied electrowetting-actuated condensation on hydrophobic surfaces, aiming for enhancement of heat transfer in dropwise condensation. The idea is to use suitably structured patterns of micro-electrodes that generate a heterogeneous electric field at the interface and thereby promote both the condensation itself and the shedding of condensed drops. Comforting the shedding of droplets on electrowetting-functionalized surfaces allows more condensing surface area for re-nucleation of small droplets, leading to higher condensation rates. Possible applications of this innovative concept include heat pipes for (micro) coolers in electronics as well as in more efficient heat exchangers. We acknowledge financial support by the Dutch Technology Foundation STW, which is part of the Netherlands Organization for Scientific Research (NWO), within the VICI program.

Investigation of concrete containing condensed silica fume.

DOT National Transportation Integrated Search

1986-01-01

The properties of hydraulic cement concretes containing silica fume were investigated to assess their suitability for use in overlays with s minimum thickness of 1 1/4 in. The properties studied were compressive and flexural strengths, bond strength,...

Quantification of chromatin condensation level by image processing.

PubMed

Irianto, Jerome; Lee, David A; Knight, Martin M

2014-03-01

The level of chromatin condensation is related to the silencing/activation of chromosomal territories and therefore impacts on gene expression. Chromatin condensation changes during cell cycle, progression and differentiation, and is influenced by various physicochemical and epigenetic factors. This study describes a validated experimental technique to quantify chromatin condensation. A novel image processing procedure is developed using Sobel edge detection to quantify the level of chromatin condensation from nuclei images taken by confocal microscopy. The algorithm was developed in MATLAB and used to quantify different levels of chromatin condensation in chondrocyte nuclei achieved through alteration in osmotic pressure. The resulting chromatin condensation parameter (CCP) is in good agreement with independent multi-observer qualitative visual assessment. This image processing technique thereby provides a validated unbiased parameter for rapid and highly reproducible quantification of the level of chromatin condensation. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Expectations for Particulate Contamination Relevant to in Situ Atmospheric Sampling for Compositional Analysis at Uranus

NASA Astrophysics Data System (ADS)

Wong, M. H.

2017-12-01

NASA and ESA are considering options for in situ science with atmospheric entry probes to the ice giants Uranus and Neptune. Nominal probe entry mass is in the 300-kg range, although a miniaturized secondary probe option is being studied in the 30-kg range. In all cases, compositional sampling would commence near the 100-mbar level at Uranus, after ejection of the heat shield and deployment of the descent parachute. In this presentation, I review existing literature on the composition, mass loading, and vertical distribution of condensed material that the probe may encounter. Sample inlets for measurement of the gas composition should be heated to avoid potential buildup of condensate, which would block the flow of atmospheric gas into composition sensors. Heating rate and temperature values -- sufficient to keep sample inlets clean under various assumptions -- will be presented. Three main types of condensed material will be considered: Stratospheric hydrocarbon ices: Solar UV photolyzes CH4, leading to the production of volatile hydrocarbons with higher C/H ratios. These species diffuse from their production regions into colder levels where the ices of C2H2, C2H6, and C4H2 condense. Some studies have also considered condensation of C3H8, C4H10, C6H6, and C6H2. Gunk: The hydrocarbon ices are thought to become polymerized due to irradiation from solar UV. The exact composition of the resulting gunk is not known. Solid-state photochemical processing may produce the traces of reddish (blue-absorbing) haze material, present in the troposphere at temperatures warm enough to sublimate the simple hydrocarbon ices. Tropospheric ices: In the region accessible to probes under study (P < 10 bar), much thicker condensation clouds may form from volatile gases CH4, NH3, and H2S. If large amounts of NH3 are sequestered in the deeper H2O liquid cloud, then the S/N ratio could exceed 1 in the probe-accessible region of the atmosphere, leading to NH4SH and H2S ices below the CH4-ice cloud deck. Otherwise, NH4SH and NH3 ices would be found. This work is supported by a grant from the NASA Planetary Science Deep Space Small Satellite Program to the Small Next-generation Atmospheric Probe (SNAP) mission concept study (PI: Kunio Sayanagi).

Trichocyanines: a Red-Hair-Inspired Modular Platform for Dye-Based One-Time-Pad Molecular Cryptography.

PubMed

Leone, Loredana; Pezzella, Alessandro; Crescenzi, Orlando; Napolitano, Alessandra; Barone, Vincenzo; d'Ischia, Marco

2015-06-01

Current molecular cryptography (MoCryp) systems are almost exclusively based on DNA chemistry and reports of cryptography technologies based on other less complex chemical systems are lacking. We describe herein, as proof of concept, the prototype of the first asymmetric MoCryp system, based on an 8-compound set of a novel bioinspired class of cyanine-type dyes called trichocyanines. These novel acidichromic cyanine-type dyes inspired by red hair pigments were synthesized and characterized with the aid of density functional theory (DFT) calculations. Trichocyanines consist of a modular scaffold easily accessible via an expedient condensation of 3-phenyl- or 3-methyl-2H-1,4-benzothiazines with N-dimethyl- or o-methoxyhydroxy-substituted benzaldehyde or cinnamaldehyde derivatives. The eight representative members synthesized herein can be classified as belonging to two three-state systems tunable through four different control points. This versatile dye platform can generate an expandable palette of colors and appears to be specifically suited to implement an unprecedented single-use asymmetric molecular cryptography system. With this system, we intend to pioneer the translation of digital public-key cryptography into a chemical-coding one-time-pad-like system.

Trichocyanines: a Red-Hair-Inspired Modular Platform for Dye-Based One-Time-Pad Molecular Cryptography

PubMed Central

Leone, Loredana; Pezzella, Alessandro; Crescenzi, Orlando; Napolitano, Alessandra; Barone, Vincenzo; d’Ischia, Marco

2015-01-01

Current molecular cryptography (MoCryp) systems are almost exclusively based on DNA chemistry and reports of cryptography technologies based on other less complex chemical systems are lacking. We describe herein, as proof of concept, the prototype of the first asymmetric MoCryp system, based on an 8-compound set of a novel bioinspired class of cyanine-type dyes called trichocyanines. These novel acidichromic cyanine-type dyes inspired by red hair pigments were synthesized and characterized with the aid of density functional theory (DFT) calculations. Trichocyanines consist of a modular scaffold easily accessible via an expedient condensation of 3-phenyl- or 3-methyl-2H-1,4-benzothiazines with N-dimethyl- or o-methoxyhydroxy-substituted benzaldehyde or cinnamaldehyde derivatives. The eight representative members synthesized herein can be classified as belonging to two three-state systems tunable through four different control points. This versatile dye platform can generate an expandable palette of colors and appears to be specifically suited to implement an unprecedented single-use asymmetric molecular cryptography system. With this system, we intend to pioneer the translation of digital public-key cryptography into a chemical-coding one-time-pad-like system. PMID:26246999

Verification testing of the compression performance of the HEVC screen content coding extensions

NASA Astrophysics Data System (ADS)

Sullivan, Gary J.; Baroncini, Vittorio A.; Yu, Haoping; Joshi, Rajan L.; Liu, Shan; Xiu, Xiaoyu; Xu, Jizheng

2017-09-01

This paper reports on verification testing of the coding performance of the screen content coding (SCC) extensions of the High Efficiency Video Coding (HEVC) standard (Rec. ITU-T H.265 | ISO/IEC 23008-2 MPEG-H Part 2). The coding performance of HEVC screen content model (SCM) reference software is compared with that of the HEVC test model (HM) without the SCC extensions, as well as with the Advanced Video Coding (AVC) joint model (JM) reference software, for both lossy and mathematically lossless compression using All-Intra (AI), Random Access (RA), and Lowdelay B (LB) encoding structures and using similar encoding techniques. Video test sequences in 1920×1080 RGB 4:4:4, YCbCr 4:4:4, and YCbCr 4:2:0 colour sampling formats with 8 bits per sample are tested in two categories: "text and graphics with motion" (TGM) and "mixed" content. For lossless coding, the encodings are evaluated in terms of relative bit-rate savings. For lossy compression, subjective testing was conducted at 4 quality levels for each coding case, and the test results are presented through mean opinion score (MOS) curves. The relative coding performance is also evaluated in terms of Bjøntegaard-delta (BD) bit-rate savings for equal PSNR quality. The perceptual tests and objective metric measurements show a very substantial benefit in coding efficiency for the SCC extensions, and provided consistent results with a high degree of confidence. For TGM video, the estimated bit-rate savings ranged from 60-90% relative to the JM and 40-80% relative to the HM, depending on the AI/RA/LB configuration category and colour sampling format.

Sensitive Spectrophotometric Method for Quantitation of Guaifenesin and Dropropizine in Their Dosage Forms

PubMed Central

Abdallah, Ola M.

2010-01-01

Guaifenesin and dropropizine were analyzed through oxidation with periodic acid to give formaldehyde which was allowed to condense with 4-Amino-5-hydrazino-4H [1,2,4]-triazole-3-thiol (AHTT). The condensation product was further oxidized to yield a purple colored compound with maximum absorption at 550 nm. Beer's law was obeyed in the range of 5–45 μg mL−1 for guaifenesin and 10–80 μg mL−1 for dropropizine. Both drugs were also successfully determined in their dosage forms. PMID:20671996

Film condensation in a horizontal rectangular duct

NASA Technical Reports Server (NTRS)

Lu, Qing; Suryanarayana, N. V.

1993-01-01

Condensation heat transfer in a horizontal rectangular duct was experimentally and analytically investigated. To prevent the dripping of condensate on the film, the experiment was conducted inside a horizontal rectangular duct with vapor condensing only on the bottom cooled plate of the duct. R-113 and FC-72 (Fluorinert Electronic Fluid developed by the 3M Company) were used as the condensing fluids. The experimental program included measurements of film thickness, local and average heat transfer coefficients, wave length, wave speed, and a study of wave initiation. The measured film thickness was used to obtain the local heat transfer coefficient. The wave initiation was studied both with condensation and with an adiabatic air-liquid flow. The test sections used in both experiments were identical.

A Deterministic Computational Procedure for Space Environment Electron Transport

NASA Technical Reports Server (NTRS)

Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamcyk, Anne M.

2010-01-01

A deterministic computational procedure for describing the transport of electrons in condensed media is formulated to simulate the effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The primary purpose for developing the procedure is to provide a means of rapidly performing numerous repetitive transport calculations essential for electron radiation exposure assessments for complex space structures. The present code utilizes well-established theoretical representations to describe the relevant interactions and transport processes. A combined mean free path and average trajectory approach is used in the transport formalism. For typical space environment spectra, several favorable comparisons with Monte Carlo calculations are made which have indicated that accuracy is not compromised at the expense of the computational speed.

Circumstellar Dust in Symbiotic Novae

NASA Astrophysics Data System (ADS)

Jurkic, T.; Kotnik-Karuza, D.

2015-12-01

We present a model of inner dust regions around the cool Mira component of the two symbiotic novae, RR Tel and HM Sge, based on the near-IR photometry, ISO spectra and mid-IR interferometry. The dust properties were determined using the DUSTY code. A compact circumstellar silicate dust shell with inner dust shell temperatures between 900 K and 1300 K and of moderate optical depth can explain all the observations. RR Tel shows the presence of an equatorially enhanced dust density during minimum obscuration. Obscuration events are explained by an increase in optical depth caused by the newly condensed dust. The mass loss rates are significantly higher than in intermediate-period single Miras but in agreement with longer-period O-rich AGB stars.

The NCS code of practice for the quality assurance and control for volumetric modulated arc therapy

NASA Astrophysics Data System (ADS)

Mans, Anton; Schuring, Danny; Arends, Mark P.; Vugts, Cornelia A. J. M.; Wolthaus, Jochem W. H.; Lotz, Heidi T.; Admiraal, Marjan; Louwe, Rob J. W.; Öllers, Michel C.; van de Kamer, Jeroen B.

2016-10-01

In 2010, the NCS (Netherlands Commission on Radiation Dosimetry) installed a subcommittee to develop guidelines for quality assurance and control for volumetric modulated arc therapy (VMAT) treatments. The report (published in 2015) has been written by Dutch medical physicists and has therefore, inevitably, a Dutch focus. This paper is a condensed version of these guidelines, the full report in English is freely available from the NCS website www.radiationdosimetry.org. After describing the transition from IMRT to VMAT, the paper addresses machine quality assurance (QA) and treatment planning system (TPS) commissioning for VMAT. The final section discusses patient specific QA issues such as the use of class solutions, measurement devices and dose evaluation methods.

Molecular detection of Staphylococcus aureus resistant to temperature in milk and its products

NASA Astrophysics Data System (ADS)

Sutejo, Stephani Valentina Harda; Amarantini, Charis; Budiarso, Tri Yahya

2017-11-01

Contamination of Staphylococcus aureus on milk can cause intoxication and infection by Staphylococcal enterotoxin. It has nuc gene, coding thermonuclease enzyme (TNase) that is responsible for nature of resistance in the heating process. This study was conducted to identify nuc gene of as S. aureus isolated from milk and its products like ultra-high temperature, sterile milk, sweetened condensed milk, formula milk, café/milk street traders and fresh milk. Biochemical identification was conducted by using carbohydrate fermentation tests and confirmed by API Staph. Molecular confirmation by amplification of nuc gene using PCR. Based on the results of confirmation using API Staph, all isolates were confirmed as S. aureus with index determinant percentage of 97%. An amplicon product of 270 bp was gained in all isolates. It is concluded that isolate of S. aureus has nuc gene.

High Stability Performance of Quinary Indium Gallium Zinc Aluminum Oxide Films and Thin-Film Transistors Deposited Using Vapor Cooling Condensation Method

NASA Astrophysics Data System (ADS)

Lin, Yung-Hao; Lee, Ching-Ting

2017-08-01

High-quality indium gallium zinc aluminum oxide (IGZAO) thin films with various Al contents have been deposited using the vapor cooling condensation method. The electron mobility of the IGZAO films was improved by 89.4% on adding Al cation to IGZO film. The change in the electron concentration and mobility of the IGZAO films was 7.3% and 7.0%, respectively, when the temperature was changed from 300 K to 225 K. These experimental results confirm the high performance and stability of the IGZAO films. The performance stability mechanisms of IGZAO thin-film transistors (TFTs) were investigated in comparison with IGZO TFTs.

Ultrahigh Molecular Weight Aromatic Siloxane Polymers

NASA Technical Reports Server (NTRS)

Ludwick, L. M.

1983-01-01

Silphenylene-siloxane polymers can be prepared by a condensation reaction of a diol 1,4-bis(hydroxydimethylsilyl)benzene and a silane bis(dimethylamino)dimethylsilane. Using a stepwise condensation technique, a polymer (R=CH3) with a molecular weight in excess of 1.0 x 1 million has been produced. The polymer exhibits increased thermal stability, compared to a methyl siloxane polymer without the aromatic phenyl ring in the backbone. The use of bis(dimethylamino)methylvinylsilane should allow for ready crosslinking at the vinyl sites (R=-CH=CH2) introduced into the backbone. However, under the conditions of the reaction system a high molecular weight polymer was not obtained or the polymer underwent a crosslinking process during the synthesis.

Dimethylsulfide/cloud condensation nuclei/climate system - Relevant size-resolved measurements of the chemical and physical properties of atmospheric aerosol particles

NASA Technical Reports Server (NTRS)

Quinn, P. K.; Covert, D. S.; Bates, T. S.; Kapustin, V. N.; Ramsey-Bell, D. C.; Mcinnes, L. M.

1993-01-01

The mass and number relationships occurring within the atmospheric dimethylsulfide/cloud condensation nuclei (CCN)/climate system, using simultaneous measurements of particulate phase mass size distributions of nss SO4(2-), methanesulfonic acid (MSA), and NH4(+); number size distributions of particles having diameters between 0.02 and 9.6 microns; CCN concentrations at a supersaturation of 0.3 percent; relative humidity; and temperature, obtained for the northeastern Pacific Ocean in April and May 1991. Based on these measurements, particulate nss SO4(2-), MSA, and NH4(+) mass appeared to be correlated with both particle effective surface area and number in the accumulation mode size range (0.16 to 0.5 micron). No correlations were found in the size range below 0.16 micron. A correlation was also found between nss SO4(2-) mass and the CCN number concentration, such that a doubling of the SO4(2-) mass corresponded to a 40 percent increase in the CCN number concentration. However, no correlation was found between MSA mass and CCN concentration.

Mesoscopic modelling and simulation of soft matter.

PubMed

Schiller, Ulf D; Krüger, Timm; Henrich, Oliver

2017-12-20

The deformability of soft condensed matter often requires modelling of hydrodynamical aspects to gain quantitative understanding. This, however, requires specialised methods that can resolve the multiscale nature of soft matter systems. We review a number of the most popular simulation methods that have emerged, such as Langevin dynamics, dissipative particle dynamics, multi-particle collision dynamics, sometimes also referred to as stochastic rotation dynamics, and the lattice-Boltzmann method. We conclude this review with a short glance at current compute architectures for high-performance computing and community codes for soft matter simulation.

Thermodynamic Model of Afterburning in Explosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhl, A L; Howard, M; Fried, L

2003-04-23

Thermodynamic states encountered during afterburning of explosion products gases in air were analyzed with the Cheetah code. Results are displayed in the form of Le Chatelier diagrams: the locus of states of specific internal energy versus temperature, for six different condensed explosives charges. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f ( T ) suitable for specifying the thermodynamic properties required for gas-dynamic models of afterburning in explosions.

16 CFR 305.4 - Prohibited acts.

Code of Federal Regulations, 2014 CFR

2014-01-01

... advertisement, with respect to the energy use or efficiency or, in the case of showerheads, faucets, water... showerheads, faucets, water closets and urinals, water use of such product, or cost of energy consumed by such... conditioners, pulse combustion and condensing furnaces, fluorescent lamp ballasts, showerheads, faucets, water...

On the Monte Carlo simulation of electron transport in the sub-1 keV energy range.

PubMed

Thomson, Rowan M; Kawrakow, Iwan

2011-08-01

The validity of "classic" Monte Carlo (MC) simulations of electron and positron transport at sub-1 keV energies is investigated in the context of quantum theory. Quantum theory dictates that uncertainties on the position and energy-momentum four-vectors of radiation quanta obey Heisenberg's uncertainty relation; however, these uncertainties are neglected in "classical" MC simulations of radiation transport in which position and momentum are known precisely. Using the quantum uncertainty relation and electron mean free path, the magnitudes of uncertainties on electron position and momentum are calculated for different kinetic energies; a validity bound on the classical simulation of electron transport is derived. In order to satisfy the Heisenberg uncertainty principle, uncertainties of 5% must be assigned to position and momentum for 1 keV electrons in water; at 100 eV, these uncertainties are 17 to 20% and are even larger at lower energies. In gaseous media such as air, these uncertainties are much smaller (less than 1% for electrons with energy 20 eV or greater). The classical Monte Carlo transport treatment is questionable for sub-1 keV electrons in condensed water as uncertainties on position and momentum must be large (relative to electron momentum and mean free path) to satisfy the quantum uncertainty principle. Simulations which do not account for these uncertainties are not faithful representations of the physical processes, calling into question the results of MC track structure codes simulating sub-1 keV electron transport. Further, the large difference in the scale at which quantum effects are important in gaseous and condensed media suggests that track structure measurements in gases are not necessarily representative of track structure in condensed materials on a micrometer or a nanometer scale.

Preliminary Image Map of the 2007 Witch Fire Perimeter, Ramona Quadrangle, San Diego County, California

USGS Publications Warehouse

Clark, Perry S.; Scratch, Wendy S.; Bias, Gaylord W.; Stander, Gregory B.; Sexton, Jenne L.; Krawczak, Bridgette J.

2008-01-01

In the fall of 2007, wildfires burned out of control in southern California. The extent of these fires encompassed large geographic areas that included a variety of landscapes from urban to wilderness. The U.S. Geological Survey National Geospatial Technical Operations Center (NGTOC) is currently (2008) developing a quadrangle-based 1:24,000-scale image map product. One of the concepts behind the image map product is to provide an updated map in electronic format to assist with emergency response. This image map is one of 55 preliminary image map quadrangles covering the areas burned by the southern California wildfires. Each map is a layered, geo-registered Portable Document Format (.pdf) file. For more information about the layered geo-registered .pdf, see the readme file (http://pubs.usgs.gov/of/2008/1029/downloads/CA_Agua_Dulce_of2008-1029_README.txt). To view the areas affected and the quadrangles mapped in this preliminary project, see the map index (http://pubs.usgs.gov/of/2008/1029/downloads/CA_of2008_1029-1083_index.pdf) provided with this report.

Binding mechanism investigations guiding the synthesis of novel condensed 1,4-dihydropyridine derivatives with L-/T-type calcium channel blocking activity.

PubMed

Schaller, David; Gündüz, Miyase Gözde; Zhang, Fang Xiong; Zamponi, Gerald W; Wolber, Gerhard

2018-05-23

Nifedipine and isradipine are prominent examples of calcium channel blockers with a 1,4-dihydropyridine (DHP) scaffold. Although successfully used in clinics since decades for the treatment of hypertension, the binding mechanism to their target, the L-type voltage-gated calcium channel Cav1.2, is still incompletely understood. Recently, novel DHP derivatives with a condensed ring system have been discovered that show distinct selectivity profiles to different calcium channel subtypes. This property renders this DHP class as a promising tool to achieve selectivity towards distinct calcium channel subtypes. In this study, we identified a common binding mode for prominent DHPs nifedipine and isradipine using docking and pharmacophore analysis that is also able to explain the structure-activity relationship of a small subseries of DHP derivatives with a condensed ring system. These findings were used to guide the synthesis of twenty-two novel DHPs. An extensive characterization using 1 H NMR, 13 C NMR, mass spectra and elemental analysis was followed by whole cell patch clamp assays for analyzing activity at Cav1.2 and Cav3.2. Two compounds were identified with significant activity against Cav1.2. Additionally, we identified four compounds active against Cav3.2 of which three were selective over Cav1.2. Novel binding modes were analyzed using docking and pharmacophore analysis as well as molecular dynamics simulations. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Formation of CO2, H2 and condensed carbon from siderite dissolution in the 200-300 °C range and at 50 MPa

NASA Astrophysics Data System (ADS)

Milesi, Vincent; Guyot, François; Brunet, Fabrice; Richard, Laurent; Recham, Nadir; Benedetti, Marc; Dairou, Julien; Prinzhofer, Alain

2015-04-01

Laboratory experiments were conducted to investigate the chemical processes governing the carbon speciation associated to hydrothermal decomposition of siderite. Experiments were carried out in sealed gold capsules using synthetic siderite and deionised water. The samples were reacted at 200 and 300 °C, under a pressure of 50 MPa. Siderite dissolved to reach the 3FeCO3 + H2O = Fe3O4 + 3CO2 + H2 equilibrium and magnetite, Fe3O4, was produced accordingly. The gas phase was dominated by CO2, H2 and CH4, the latter being in strong thermodynamic disequilibrium with CO2. Contrary to the other gas products, H2 concentration was found to decrease with run duration. TEM observations showed the occurrence of condensed carbon phases at the surfaces of magnetite and residual siderite grains. Thermodynamic calculations predict the formation of condensed carbon in the experiments according to the reaction: CO2 + 2H2 ⇒ C + 2H2O, which accounted for the observed H2 concentration decrease up to the point where H2 and CO2 activities were buffered by the graphite-siderite-magnetite assemblage. The well-organized structure of the carbon coating around magnetite emphasizes the high catalytic potential of magnetite surface for carbon reduction and polymerization. The formation of such C-rich phases may represent a potential source of CH4 by hydrogenation. On the other hand, the catalysis of Fischer-Tropsch type reactions may be poisoned by the presence of carbon coating on mineral surfaces. In any case, this study also demonstrates that abiotic H2 generation by water reduction, widely studied in recent years in ultrabasic contexts, can also occur in sedimentary contexts where siderite is present. We show that, in the latter case, natural H2 concentration will be buffered by a condensed carbon phase associated with magnetite.