WorldWideScience

Sample records for angew chem int

  1. Chem systems

    International Nuclear Information System (INIS)

    This paper reports that world styrene demand, paced by a near doubling of combined requirements in East Asia and Oceania, could reach 19.3 million metric tons by 2000, an average growth rate of 3.7%/year. So concludes Chem Systems Inc., Tarrytown, N.Y., in a study of world styrene markets through the end of the century. Pacific Rim styrene production and consumption throughout the 1990s are predicted to make up increasingly larger shares of world markets, while demand and production lag in the U.S. and western Europe. Demand and capacity in other parts of the world will grow in real terms, increasing combined market shares only slightly. Most of the increase will be driven by demand in East Asia and Oceania, where consumption by century's end is expected to increase 4.48 million metric tons from 2.25 million tons in 1991. Meantime, Japan's styrene demand in 2000 is projected at 2.64 million tons, a 500,000 ton increase from 1991 demand but a net market loss of 1.9%

  2. PubChem

    Data.gov (United States)

    U.S. Department of Health & Human Services — PubChem contains the chemical structures of small organic molecules and information on their biological activities. PubChem includes substance information, compound...

  3. Some comments on the paper: Controllability of fractional neutral stochastic functional differential systems, Z. Angew. Math. Phys. 65 (2014), no. 5, 941-959

    Science.gov (United States)

    Pierri, Michelle; O'Regan, Donal

    2016-04-01

    The abstract results and applications presented in "Controllability of fractional neutral stochastic functional differential systems, Z. Angew. Math. Phys. 65 (2014), no. 5, 941-959, are not correct. Moreover, the class of differential control problems studied in [1] is not H-controllable.

  4. ChemIDplus

    Data.gov (United States)

    U.S. Department of Health & Human Services — Chemical database is a dictionary of over 400,000 chemicals (names, synonyms, and structures). ChemIDplus includes links to NLM and other databases and resources,...

  5. Int

    OpenAIRE

    Abdullah Özkaya; Ihsan Yilmaz; Zeynep Alkin; Yalcin Karakucuk; Ahmet Taylan Yazici

    2016-01-01

    Congenital optic nerve abnormalities may rarely cause choroidal neovascularization (CNV). This case report summarizes the clinical and therapeutic outcomes of a 7-year-old boy with unilateral CNV secondary to morning glory syndrome associated with acute visual acuity loss. The patient was successfully treated with a single intravitreal ranibizumab injection. One month after the injection the visual acuity increased and optic coherence tomography (OCT) showed a decrease in the intraretinal flu...

  6. ChemSpell Web Service API

    Data.gov (United States)

    U.S. Department of Health & Human Services — The ChemSpell Web Service API provides chemical name spell checking and chemical name synonym look-up. ChemSpell contains more than 1.3 million chemical names...

  7. Introductory statistics with intRo

    OpenAIRE

    Hare, Eric; Kaplan, Andee

    2016-01-01

    intRo is a web-based application for performing basic data analysis and statistical routines. Leveraging the power of R and Shiny, intRo implements common statistical functions in an extensible modular structure, while including a point-and-click interface for the novice statistician. This simplicity lends itself to a natural presentation in an introductory statistics course as a substitute for other commonly used statistical software packages. intRo is currently deployed at the URL http://ww...

  8. PubChem Substance and Compound databases.

    Science.gov (United States)

    Kim, Sunghwan; Thiessen, Paul A; Bolton, Evan E; Chen, Jie; Fu, Gang; Gindulyte, Asta; Han, Lianyi; He, Jane; He, Siqian; Shoemaker, Benjamin A; Wang, Jiyao; Yu, Bo; Zhang, Jian; Bryant, Stephen H

    2016-01-01

    PubChem (https://pubchem.ncbi.nlm.nih.gov) is a public repository for information on chemical substances and their biological activities, launched in 2004 as a component of the Molecular Libraries Roadmap Initiatives of the US National Institutes of Health (NIH). For the past 11 years, PubChem has grown to a sizable system, serving as a chemical information resource for the scientific research community. PubChem consists of three inter-linked databases, Substance, Compound and BioAssay. The Substance database contains chemical information deposited by individual data contributors to PubChem, and the Compound database stores unique chemical structures extracted from the Substance database. Biological activity data of chemical substances tested in assay experiments are contained in the BioAssay database. This paper provides an overview of the PubChem Substance and Compound databases, including data sources and contents, data organization, data submission using PubChem Upload, chemical structure standardization, web-based interfaces for textual and non-textual searches, and programmatic access. It also gives a brief description of PubChem3D, a resource derived from theoretical three-dimensional structures of compounds in PubChem, as well as PubChemRDF, Resource Description Framework (RDF)-formatted PubChem data for data sharing, analysis and integration with information contained in other databases. PMID:26400175

  9. Comment on: "Fundamental flows with nonlinear slip conditions: exact solutions", by R. Ellahi, T. Hayat, F. M. Mahomed and A. Zeeshan, Z. Angew. Math. Phys. 61 (2010) 877-888

    Science.gov (United States)

    El-Mistikawy, Tarek M. A.

    2011-12-01

    In their article (Fundamental flows with nonlinear slip conditions: exact solutions, R. Ellahi, T. Hayat, F. M. Mahomed and A. Zeeshan, Z. Angew. Math. Phys. 61 (2010) 877-888.), the authors considered three simple cases of the steady flow of a third grade fluid between parallel plates with slip conditions; namely, Couette flow, Poiseuille flow, and generalized Couette flow. They obtained exact solutions, which were utilized in a way that did not lead to useful results. Their conclusion that the Couette flow cannot be obtained from the generalized Couette flow, by dropping the pressure gradient, is incorrect. Meaningful results based on their solution are herein presented.

  10. PubChem Power User Gateway (PUG)

    Data.gov (United States)

    U.S. Department of Health & Human Services — PUG provides access to PubChem services via a programmatic interface. Users may download data, initiate chemical structure searches, standardize chemical structures...

  11. A History of ChemMatters Magazine

    Science.gov (United States)

    Tinnesand, Michael J.

    2007-01-01

    ChemMatters, the chemistry magazine published since 1983, has always provided interesting topics for chemistry students. The American Chemical Society publishes the magazine and many well-known authors like Isaac Asimov, Glen Seaborg and Derek Davenport have contributed to the magazine and the magazine has succeeded in its goal of demystifying…

  12. The Best of Chem 13 News

    Science.gov (United States)

    Thorsen, Kathy

    1999-07-01

    This column is designed to give JCE readers a few highlights from Chem 13 News, a monthly publication for chemistry educators from the University of Waterloo in Ontario, Canada, and provides annotations describing a particular activity or a variety of sources from which new and creative ideas can be extracted.

  13. "CHEM"opera for Chemistry Education

    Science.gov (United States)

    Chung, Yong Hee

    2013-01-01

    "CHEM"opera is an opera blended with demonstrations of chemical reactions. It has been produced and performed twice by chemistry undergraduate students at Hallym University in South Korea. It aims to demonstrate interesting chemical reactions to chemistry students, children and the public and to facilitate their understanding of the role…

  14. ChemNetzBib – Medien digital

    OpenAIRE

    Kropf, Katrin

    2010-01-01

    Wer träumt nicht davon, bequem von zu Hause aus Medien aus der Bibliothek auszuleihen. Ohne nerviges Anstellen in die Schlange an der Ausleihtheke oder sich an die Öffnungszeiten der Bibliothek zu halten. Diesen Dienst bietet die Stadtbibliothek Chemnitz mit ihrem ChemNetzBib an, der sogenannten „Onleihe“. Ein paar Klicks und schon ist das digitale Medium auf dem PC des Users.

  15. Analysis list: INTS3 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available INTS3 Uterus + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/INTS3.1....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/INTS3.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/INTS...3.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/INTS3.Uterus.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Uterus.gml ...

  16. The IntSat method for integer linear programming

    OpenAIRE

    Nieuwenhuis, Robert Lukas Mario

    2014-01-01

    Conflict-Driven Clause-Learning (CDCL) SAT solvers can automatically solve very large real-world problems. To go beyond, and in particular in order to solve and optimize problems involving linear arithmetic constraints, here we introduce IntSat, a generalization of CDCL to Integer Linear Programming (ILP). Our simple 1400-line C++ prototype IntSat implementation already shows some competitiveness with commercial solvers such as CPLEX or Gurobi. Here we describe this new IntSat ILP solving met...

  17. ConfChem Conference on Flipped Classroom: Spring 2014 ConfChem Virtual Poster Session

    Science.gov (United States)

    Belford, Robert E.; Stoltzfus, Matthew; Houseknecht, Justin B.

    2015-01-01

    This communication describes the virtual poster session of the Flipped Classroom online ConfChem conference that was hosted by the ACS CHED Committee on Computers in Chemical Education (CCCE) from May 9 to June 12, 2014. During the conference's online discussions, it became evident that multiple participants who were not presenting papers had been…

  18. Using ChemBank to probe chemical biology.

    Science.gov (United States)

    Petri Seiler, Kathleen; Kuehn, Heidi; Pat Happ, Mary; Decaprio, Dave; Clemons, Paul A

    2008-06-01

    ChemBank (http://chembank.broad.harvard.edu/) is a public, Web-based informatics environment. ChemBank stores and makes freely available data derived from small molecules and small-molecule screens and has resources for relating and studying these data. Currently, ChemBank stores information on hundreds of thousands of small molecules and hundreds of biomedically relevant assays performed at the Broad Institute screening center. Web-based analysis tools are available within ChemBank to study the relationships between small molecules, cell measurements, and cell states. This unit demonstrates the use of ChemBank data to ask and answer questions relating to chemical biology and screening experiments contained within ChemBank. PMID:18551413

  19. Another new plan for EniChem

    International Nuclear Information System (INIS)

    ENI (Milan), Italy's state-owned petrochemicals conglomerate, is preparing a new business plan for EniChem in light of the continuing economic crisis, according to Franc Bernabe, managing director of ENI. The aim is a complete overhaul of its interests in the industry and the elimination of loss-making sectors. The group intends to remain in the chemical industry. We consider the sector one of our fundamental commitments, Bernabe says. However, the chemicals sector must be restructured. It cannot be left to lose money and it cannot rely on welfare. While ENI sets about another restructuring of its chemicals interests, the Italian government has published its policy paper on privatization, containing its vision of the ENI group's future. It calls for the company to accelerate its refocusing around its core businesses and to speed up sales of noncore companies that need to be returned to profitability

  20. PubChem3D: Conformer generation

    Directory of Open Access Journals (Sweden)

    Bolton Evan E

    2011-01-01

    Full Text Available Abstract Background PubChem, an open archive for the biological activities of small molecules, provides search and analysis tools to assist users in locating desired information. Many of these tools focus on the notion of chemical structure similarity at some level. PubChem3D enables similarity of chemical structure 3-D conformers to augment the existing similarity of 2-D chemical structure graphs. It is also desirable to relate theoretical 3-D descriptions of chemical structures to experimental biological activity. As such, it is important to be assured that the theoretical conformer models can reproduce experimentally determined bioactive conformations. In the present study, we investigate the effects of three primary conformer generation parameters (the fragment sampling rate, the energy window size, and force field variant upon the accuracy of theoretical conformer models, and determined optimal settings for PubChem3D conformer model generation and conformer sampling. Results Using the software package OMEGA from OpenEye Scientific Software, Inc., theoretical 3-D conformer models were generated for 25,972 small-molecule ligands, whose 3-D structures were experimentally determined. Different values for primary conformer generation parameters were systematically tested to find optimal settings. Employing a greater fragment sampling rate than the default did not improve the accuracy of the theoretical conformer model ensembles. An ever increasing energy window did increase the overall average accuracy, with rapid convergence observed at 10 kcal/mol and 15 kcal/mol for model building and torsion search, respectively; however, subsequent study showed that an energy threshold of 25 kcal/mol for torsion search resulted in slightly improved results for larger and more flexible structures. Exclusion of coulomb terms from the 94s variant of the Merck molecular force field (MMFF94s in the torsion search stage gave more accurate conformer models at

  1. IntEnz, the integrated relational enzyme database.

    Science.gov (United States)

    Fleischmann, Astrid; Darsow, Michael; Degtyarenko, Kirill; Fleischmann, Wolfgang; Boyce, Sinéad; Axelsen, Kristian B; Bairoch, Amos; Schomburg, Dietmar; Tipton, Keith F; Apweiler, Rolf

    2004-01-01

    IntEnz is the name for the Integrated relational Enzyme database and is the official version of the Enzyme Nomenclature. The Enzyme Nomenclature comprises recommendations of the Nomenclature Committee of the International Union of Bio chemistry and Molecular Biology (NC-IUBMB) on the nomenclature and classification of enzyme-catalysed reactions. IntEnz is supported by NC-IUBMB and contains enzyme data curated and approved by this committee. The database IntEnz is available at http://www.ebi.ac.uk/intenz. PMID:14681451

  2. PubChem3D: a new resource for scientists

    Directory of Open Access Journals (Sweden)

    Bolton Evan E

    2011-09-01

    Full Text Available Abstract Background PubChem is an open repository for small molecules and their experimental biological activity. PubChem integrates and provides search, retrieval, visualization, analysis, and programmatic access tools in an effort to maximize the utility of contributed information. There are many diverse chemical structures with similar biological efficacies against targets available in PubChem that are difficult to interrelate using traditional 2-D similarity methods. A new layer called PubChem3D is added to PubChem to assist in this analysis. Description PubChem generates a 3-D conformer model description for 92.3% of all records in the PubChem Compound database (when considering the parent compound of salts. Each of these conformer models is sampled to remove redundancy, guaranteeing a minimum (non-hydrogen atom pair-wise RMSD between conformers. A diverse conformer ordering gives a maximal description of the conformational diversity of a molecule when only a subset of available conformers is used. A pre-computed search per compound record gives immediate access to a set of 3-D similar compounds (called "Similar Conformers" in PubChem and their respective superpositions. Systematic augmentation of PubChem resources to include a 3-D layer provides users with new capabilities to search, subset, visualize, analyze, and download data. A series of retrospective studies help to demonstrate important connections between chemical structures and their biological function that are not obvious using 2-D similarity but are readily apparent by 3-D similarity. Conclusions The addition of PubChem3D to the existing contents of PubChem is a considerable achievement, given the scope, scale, and the fact that the resource is publicly accessible and free. With the ability to uncover latent structure-activity relationships of chemical structures, while complementing 2-D similarity analysis approaches, PubChem3D represents a new resource for scientists to

  3. IntAct: an open source molecular interaction database

    OpenAIRE

    Hermjakob, Henning; Montecchi-Palazzi, Luisa; Lewington, Chris; Mudali, Sugath; Kerrien, Samuel; Orchard, Sandra; Vingron, Martin; Roechert, Bernd; Roepstorff, Peter; Valencia, Alfonso; Margalit, Hanah; Armstrong, John; Bairoch, Amos Marc; Cesareni, Gianni; Sherman, David

    2004-01-01

    IntAct provides an open source database and toolkit for the storage, presentation and analysis of protein interactions. The web interface provides both textual and graphical representations of protein interactions, and allows exploring interaction networks in the context of the GO annotations of the interacting proteins. A web service allows direct computational access to retrieve interaction networks in XML format. IntAct currently contains approximately 2200 binary and complex interactions ...

  4. ChemSensor: Response to gasoline and diesel contaminated groundwater

    International Nuclear Information System (INIS)

    ChemSensor is a field portable device that uses fiber optic technology to measure levels of organic contamination in water. The device relies on partitioning of organic species into an organophyllic coating on an optical fiber to change the light transmitting properties of the fiber. The response is non-selective and dependent upon the aqueous solubility of the contaminant(s). The response of ChemSensor to water samples contaminated with gasoline or diesel fuel is discussed. Correlation of the response to the BTEX and TPH concentrations is shown. A discussion of the temporal response of ChemSensor is also provided

  5. Syns man inte, finns man inte? : GANT Swedens hantering av image och relationer via Instagram och Pinterest

    OpenAIRE

    Wängborg, Linda

    2014-01-01

    Sammanfattning Titel: Syns man inte, finns man inte? GANT Swedens hantering av image och relationer via Instagram och Pinterest. Examinationsdatum: 2014-01-07 Kurs: Examensarbete inom Medie- och kommunikationsvetenskap, Public relations och information, 15 högskolepoäng (15 ECTS). HT2013, Kandidatkurs: Medie- och kommunikationsvetenskap, 30 högskolepoäng (30 ECTS). Författare: Linda Wängborg Handledare: Jonas Jonsson Examinator: Christian Christensen Nyckelord: sociala medier, public relation...

  6. Soft Approximations and uni-int Decision Making

    CERN Document Server

    Kharal, Athar

    2010-01-01

    Notions of core, support and inversion of a soft set have been de ned and studied. Soft approximations are soft sets developed through core and support, and are used for granulating the soft space. Membership structure of a soft set has been probed in and many interesting properties presented. The mathematical apparatus developed so far in this paper yields a detailed analysis of two works viz. [N. Cagman, S. Enginoglu, Soft set theory and uni-int decision making, European Jr. of Operational Research (article in press, available online 12 May 2010)] and [N. Cagman, S. Enginoglu, Soft matrix theory and its decision making, Computers and Mathematics with Applications 59 (2010) 3308 - 3314.]. We prove (Theorem 8.1) that uni-int method of Cagman is equivalent to a core-support expression which is computationally far less expansive than uni-int. This also highlights some shortcomings in Cagman's uni-int method and thus motivates us to improve the method. We rst suggest an improvement in uni-int method and then pre...

  7. Process modeling for the Integrated Nonthermal Treatment System (INTS) study

    Energy Technology Data Exchange (ETDEWEB)

    Brown, B.W.

    1997-04-01

    This report describes the process modeling done in support of the Integrated Nonthermal Treatment System (INTS) study. This study was performed to supplement the Integrated Thermal Treatment System (ITTS) study and comprises five conceptual treatment systems that treat DOE contract-handled mixed low-level wastes (MLLW) at temperatures of less than 350{degrees}F. ASPEN PLUS, a chemical process simulator, was used to model the systems. Nonthermal treatment systems were developed as part of the INTS study and include sufficient processing steps to treat the entire inventory of MLLW. The final result of the modeling is a process flowsheet with a detailed mass and energy balance. In contrast to the ITTS study, which modeled only the main treatment system, the INTS study modeled each of the various processing steps with ASPEN PLUS, release 9.1-1. Trace constituents, such as radionuclides and minor pollutant species, were not included in the calculations.

  8. IntAct: an open source molecular interaction database.

    Science.gov (United States)

    Hermjakob, Henning; Montecchi-Palazzi, Luisa; Lewington, Chris; Mudali, Sugath; Kerrien, Samuel; Orchard, Sandra; Vingron, Martin; Roechert, Bernd; Roepstorff, Peter; Valencia, Alfonso; Margalit, Hanah; Armstrong, John; Bairoch, Amos; Cesareni, Gianni; Sherman, David; Apweiler, Rolf

    2004-01-01

    IntAct provides an open source database and toolkit for the storage, presentation and analysis of protein interactions. The web interface provides both textual and graphical representations of protein interactions, and allows exploring interaction networks in the context of the GO annotations of the interacting proteins. A web service allows direct computational access to retrieve interaction networks in XML format. IntAct currently contains approximately 2200 binary and complex interactions imported from the literature and curated in collaboration with the Swiss-Prot team, making intensive use of controlled vocabularies to ensure data consistency. All IntAct software, data and controlled vocabularies are available at http://www.ebi.ac.uk/intact. PMID:14681455

  9. Applying RESRAD-CHEM for chemical risk assessment

    International Nuclear Information System (INIS)

    RESRAD-CHEM is a multiple pathway analysis computer code to evaluate chemically contaminated sites; it was developed at Argonne National Laboratory for the US Department of Energy. The code is designed to predict human health risks from exposure to hazardous chemicals and to derive cleanup criteria for chemically contaminated soils. It consists of environmental fate and transport models and is capable of predicting chemical concentrations over time in different environmental media. The methodology used in RESRAD-CHEM for exposure assessment and risk characterization follows the US Environmental Protection Agency's guidance on Human Health Evaluation for Superfund. A user-friendly interface is incorporated for entering data, operating the code, and displaying results. RESRAD-CHEM is easy to use and is a powerful tool to assess chemical risk from environmental exposure

  10. EarthChem: Next Developments to Meet New Demands (Invited)

    Science.gov (United States)

    Lehnert, K. A.; Walker, D.; Block, K. A.; Ash, J. M.; Chan, C.

    2009-12-01

    EarthChem is a community-driven effort to facilitate the discovery, access, and preservation of geochemical data to support research and enable new and better science. After its first 4 years of development, EarthChem has established itself as a leading community resource that offers to its users a range of data services comprising: the EarthChem Portal as a central access point to geochemical data in federated databases with tools for data discovery, data access, and data analysis; the Geochemical Resource Library that serves as a repository for user-submitted data and features an online submission tool and a searchable metadata catalog; topical data collections such as the Deep Lithosphere Dataset that are developed and maintained by EarthChem; and GEOCHRON, a system for easy population and access of geochronology and thermochronology data. Growing demands for user-based data contributions, long-term data archiving, interoperability, and expanded data coverage will be addressed in EarthChem’s next development phase, during which EarthChem will enhance its information technology infrastructure, create new digital content, expand partnerships, and continue to promote the implementation of more open and standardized data reporting in geochemistry. Large emphasis will be placed on the development of services that help investigators to organize and manage their data in a way that submission of the data and metadata to EarthChem becomes effortless, seamless, and comprehensive, and that also facilitates the publication of data. The new EarthChem Repository will provide data storage and stewardship for the widest range of geochemical data sets and data collections, with tools for data submission and a data publication service that will allow users to obtain Digital Object Identifier for Scientific Primary Data (STD-DOI) to make their submitted data citable as publications. These applications are expected to ensure more efficient and timely growth of the data

  11. Construire l'ennemi intérieur

    OpenAIRE

    Ceyhan, Ayse; Jobard, Fabien; Lew, Roland; Périès, Gabriel; Roudot, Dominique; Viltard, Yves

    2003-01-01

    Le révolutionnaire, l’hérétique, me converti, le terroriste, le communiste, le Juif, l’immigré, le franc-maçon, l’espion, la cinquième colonne…, les figures de l’ennemi intérieur sont multiples. Qu'est-ce que l'ennemi intérieur sinon une construction, produit de contextes historiques, socio-politiques et géographiques différents et dont l'image constitue un puissant outil d'occultation et de légitimation des pratiques politiques pour temps de crise. Derrière ces procédés de désignation et de ...

  12. ChemAND - a system health monitor for plant chemistry

    International Nuclear Information System (INIS)

    Effective management of plant systems throughout their lifetime requires much more than data acquisition and display - it requires that the plant's system health be continually monitored and managed. AECL has developed a System Health Monitor called ChemAND for CANDU plant chemistry. ChemAND, a Chemistry ANalysis and Diagnostic system, monitors key chemistry parameters in the heat transport system, moderator-cover gas, annulus gas, and the steam cycle during full-power operation. These parameters can be used as inputs to models that calculate the effect of current plant operating conditions on the present and future health of the system. Chemistry data from each of the systems are extracted on a regular basis from the plant's Historical Data Server and are sorted according to function, e.g., indicators for condenser in-leakage, air in-leakage, heavy water leakage into the annulus gas, fuel failure, etc. Each parameter is conveniently displayed and is trended along with its alarm limits. ChemAND currently includes two analytical models developed for the balance-of-plant. The first model, ChemSolv, calculates crevice chemistry conditions in the steam generator (SG) from either the SG blowdown chemistry conditions or from a simulated condenser leak. This information can be used by plant staff to evaluate the susceptibility of the SG tubes to crevice corrosion. ChemSolv also calculates chemistry conditions throughout the steam-cycle system as determined by the transport of volatile species such as ammonia, hydrazine, morpholine, and oxygen. The second model, SLUDGE, calculates the deposit loading and distribution in the SG as a function of time, based on concentrations of corrosion product in the final feedwater for both normal and start-up conditions. Operations personnel can use this information to predict where to inspect and when to clean. (author)

  13. ChemAND - a system health monitor for plant chemistry

    International Nuclear Information System (INIS)

    Effective management of plant systems throughout their lifetime requires much more than data acquisition and display-it requires that the plant's system health be continually monitored and managed. AECL has developed a System Health Monitor called ChemAND for CANDU plant chemistry. ChemAND, a Chemistry ANalysis and Diagnostic system, monitors key chemistry parameters in the heat transport system, moderator-cover gas, annulus gas, and the steam cycle during full-power operation. These parameters can be used as inputs to models that calculate the effect of current plant operating conditions on the present and future health of the system. Chemistry data from each of the systems are extracted on a regular basis from the plant's Historical Data Server and are sorted according to function, e.g., indicators for condenser in-leakage, air in-leakage, heavy water leakage into the annulus gas, fuel failure, etc. Each parameter is conveniently displayed and is trended along with its alarm limits. ChemAND currently includes two analytical models developed for the balance-of-plant. The first model, ChemSolv, calculates crevice chemistry conditions in the steam generator (SG) from either the SG blowdown chemistry conditions or from a simulated condenser leak. This information can be used by plant staff to evaluate the susceptibility of the SG tubes to crevice corrosion. ChemSolv also calculates chemistry conditions throughout the steam cycle system, as determined by the transport of volatile species such as ammonia, hydrazine, morpholine, and oxygen. The second model, SLUDGE, calculates the deposit loading and distribution in the SG as a function of time, based on concentrations of corrosion product in the final feedwater for both normal and start-up conditions. Operations personnel can use this information to predict where to inspect and when to clean. (author)

  14. ChemAND - a system health monitor for plant chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Turner, C.W.; Mitchel, G.R.; Tosello, G.; Balakrishnan, P.V.; McKay, G.; Thompson, M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Dundar, Y.; Bergeron, M.; Laporte, R. [Hydro-Quebec, Groupe Chimie, Centrale Nucleaire Gentilly-2, Gentilly, Quebec (Canada)

    2001-03-01

    Effective management of plant systems throughout their lifetime requires much more than data acquisition and display - it requires that the plant's system health be continually monitored and managed. AECL has developed a System Health Monitor called ChemAND for CANDU plant chemistry. ChemAND, a Chemistry ANalysis and Diagnostic system, monitors key chemistry parameters in the heat transport system, moderator-cover gas, annulus gas, and the steam cycle during full-power operation. These parameters can be used as inputs to models that calculate the effect of current plant operating conditions on the present and future health of the system. Chemistry data from each of the systems are extracted on a regular basis from the plant's Historical Data Server and are sorted according to function, e.g., indicators for condenser in-leakage, air in-leakage, heavy water leakage into the annulus gas, fuel failure, etc. Each parameter is conveniently displayed and is trended along with its alarm limits. ChemAND currently includes two analytical models developed for the balance-of-plant. The first model, ChemSolv, calculates crevice chemistry conditions in the steam generator (SG) from either the SG blowdown chemistry conditions or from a simulated condenser leak. This information can be used by plant staff to evaluate the susceptibility of the SG tubes to crevice corrosion. ChemSolv also calculates chemistry conditions throughout the steam-cycle system as determined by the transport of volatile species such as ammonia, hydrazine, morpholine, and oxygen. The second model, SLUDGE, calculates the deposit loading and distribution in the SG as a function of time, based on concentrations of corrosion product in the final feedwater for both normal and start-up conditions. Operations personnel can use this information to predict where to inspect and when to clean. (author)

  15. Response to the Comment on Paper 'Water vapor Enhancement of Rates of Peroxy Radical Reactions', Int. J. Chem. Kinetics, 47, 395, 2015

    Energy Technology Data Exchange (ETDEWEB)

    Kumbhani, Sambhav R.; Cline, Taylor S.; Killian, Marie C.; Clark, Jared M.; Keeton, William J.; Hansen, Lee D.; Shirts, Randall B.; Robichaud, David J.; Hansen, Jaron C.

    2016-07-01

    Comments provided here aid in understanding the effect of water vapor on the rate of the self-reaction of HOCH2CH2O2 recently reported by Kumbhani et al. [1] Kumbhani et al. asserts that water vapor increases the rate of the HOCH2CH2O2 self-reaction by formation of an HOCH2CH2O2-H2O complex.

  16. ChemCalc: a building block for tomorrow's chemical infrastructure.

    Science.gov (United States)

    Patiny, Luc; Borel, Alain

    2013-05-24

    Web services, as an aspect of cloud computing, are becoming an important part of the general IT infrastructure, and scientific computing is no exception to this trend. We propose a simple approach to develop chemical Web services, through which servers could expose the essential data manipulation functionality that students and researchers need for chemical calculations. These services return their results as JSON (JavaScript Object Notation) objects, which facilitates their use for Web applications. The ChemCalc project http://www.chemcalc.org demonstrates this approach: we present three Web services related with mass spectrometry, namely isotopic distribution simulation, peptide fragmentation simulation, and molecular formula determination. We also developed a complete Web application based on these three Web services, taking advantage of modern HTML5 and JavaScript libraries (ChemDoodle and jQuery). PMID:23480664

  17. ChemProt: a disease chemical biology database

    DEFF Research Database (Denmark)

    Taboureau, Olivier; Nielsen, Sonny Kim; Audouze, Karine Marie Laure;

    2011-01-01

    Systems pharmacology is an emergent area that studies drug action across multiple scales of complexity, from molecular and cellular to tissue and organism levels. There is a critical need to develop network-based approaches to integrate the growing body of chemical biology knowledge with network...... biology. Here, we report ChemProt, a disease chemical biology database, which is based on a compilation of multiple chemical-protein annotation resources, as well as disease-associated protein-protein interactions (PPIs). We assembled more than 700 000 unique chemicals with biological annotation for 30...... 578 proteins. We gathered over 2-million chemical-protein interactions, which were integrated in a quality scored human PPI network of 428 429 interactions. The PPI network layer allows for studying disease and tissue specificity through each protein complex. ChemProt can assist in the in silico...

  18. Comb-e-Chem: an e-science research project

    OpenAIRE

    Frey, Jeremy G.

    2003-01-01

    The background to the Comb-e-Chem e-Science pilot project funded under the UK -Science Programme is presented and the areas being addresses within chemistry and more specifically combinatorial chemistry are disucssed. The ways in which the ideas underlying the application of computer technology can improve the production, analysis and dissemination of chemical information and knowledge in a collaborative environment are discussed.

  19. Engaging Organic Chemistry Students Using ChemDraw for iPad

    Science.gov (United States)

    Morsch, Layne A.; Lewis, Michael

    2015-01-01

    Drawing structures, mechanisms, and syntheses is a vital part of success in organic chemistry courses. ChemDraw for iPad has been used to increase classroom experiences in the preparation of high quality chemical drawings. The embedded Flick-to-Share allows for simple, real-time exchange of ChemDraw documents. ChemDraw for iPad also allows…

  20. ChemCam Passive Reflectance Spectroscopy at Gale Crater, Mars

    Science.gov (United States)

    Johnson, J. R.; Bell, J. F.; Cloutis, E.; Bender, S.; Blaney, D. L.; Ehlmann, B. L.; Gasnault, O.; Kinch, K. M.; Le Mouelic, S.; Rice, M. S.; Wiens, R. C.; DeFlores, L.; Team, M.

    2013-12-01

    The Laser-Induced Breakdown Spectrometer (LIBS) portion of the ChemCam instrument on the Mars Science Laboratory Curiosity rover uses 3 dispersive spectrometers to cover the ultraviolet (240-342 nm), visible (382-469 nm) and visible/near-infrared (474-906 nm) spectral regions at high spectral (spectra (acquired with the LIBS laser off) used to remove the background signal from the LIBS measurement. Similar 'passive' observations of the ChemCam calibration target holder can be made at similar times of day and at identical exposure times (to minimize variations from dark current). Because this target exhibits ~95% flat reflectance in the ~400-900 nm region, radiance spectra ratios (surface/calibration target) can be normalized to known calibration target lab spectra to produce relative reflectance spectra (400-900 nm) with an estimated accuracy of 10-20%. Initial results replicated the known spectral shape and overall reflectance values of the ChemCam calibration targets and green color chip on the Mastcam calibration target. Dust contamination was evident, although dust on the ChemCam calibration targets is minimized by their tilted placement on the rover deck. All ChemCam targets that were sunlit during LIBS acquisition (~80% of all measurements) provide 'dark' spectra for which relative reflectance spectra can be obtained. Owing to the dusty nature of the Gale landing sites, passive spectra observed to date exhibit spectral shapes indicative of ferric phases, similar to spectra of palagonitic soils. Most spectra are bracketed in reflectance by typical 'bright' and 'dark' spectra from the OMEGA and CRISM orbital spectrometers. Preliminary Mastcam reflectance spectra are similar, providing additional confidence regarding the first-order calibration of the ChemCam spectra. The spectral similarity to palagonitic soils is consistent with the results from the CheMin instrument for Rocknest sands. Changes in the 535 nm band depth are likely indicative of differences in

  1. ChemCam Passive Spectroscopy of the Martian Atmosphere

    Science.gov (United States)

    McConnochie, T. H.; Smith, M. D.; Wolff, M. J.; Bender, S. C.; Johnson, J. R.; Wiens, R. C.; Maurice, S.; Gasnault, O.; Barraclough, B. L.; Blaney, D. L.; DeFlores, L.; Team, M.

    2013-12-01

    The design priority of the Laser-Induced Breakdown Spectrometer (LIBS) portion of the ChemCam instrument (Wiens et al. 2012, Space Sci, Rev. 170) on the Mars Science Laboratory (MSL) Curiosity rover is its active mode, which acquires spectra of a laser induced plasma using three spectrometers. However these same spectrometers have excellent sensitivity to ambient light and so are also used independent of the laser in 'passive' mode to acquire spectra of the Martian surface (Johnson et al., 2013, LPSC #1372) and, as we will describe here, the Martian sky. Using ChemCam passive sky observations, we have successfully measured the column abundance of water vapor, molecular oxygen, and carbon dioxide gas, and with further analysis will likely be able to constrain the column abundance of ozone as well as aerosol and cloud particle properties. Although data analysis is ongoing, we currently estimate a 2 sigma precision of oxygen, and < +/- 4 % for carbon dioxide. The three ChemCam spectrometers span 240-342 nm, 382-469 nm, and 474-906 nm, respectively, with a resolution of 0.6 nm FWHM or better. Passive sky observations were obtained on sols 131, 230, and then at regular ~7 sol intervals starting on sol 278. The observation consists of acquiring spectra of light scattered by the atmosphere at two elevation angles so that the ratio of the two resulting radiance spectra yields (after removing the continuum) an extremely precise absorption spectrum with both the solar spectrum and instrument response uncertainties removed. To yield column abundances, the spectra are modeled with a discrete ordinates multiple scattering radiative transfer code that incorporates gas absorption via the correlated-k method.

  2. ChemANDTM - a system health monitor for plant chemistry

    International Nuclear Information System (INIS)

    Effective management of plant systems throughout their lifetime requires much more than data acquisition and display - it requires that the plant's system health be continually monitored and managed. AECL has developed a System Health Monitor called ChemAND for CANDU plant chemistry. ChemAND, a Chemistry ANalysis and Diagnostic system, monitors key chemistry parameters in the heat transport system, moderator-cover gas, annulus gas, and the steam cycle during full-power operation and feeds these parameters to models that calculate the effect of current plant operating conditions on the present and future health of the system. Chemistry data from each of the systems are extracted on a regular basis from the plant's Historical Data Server and are sorted according to function, e.g., indicators for condenser in-leakage, air in-leakage, heavy water leakage into the annulus gas, fuel failure, etc. Each parameter is conveniently displayed and is trended along with its alarm limits. ChemAND currently has two analytical models developed for the balance-of-plant. CHEMSOLV calculates crevice chemistry conditions in the steam generator (SG) from either the SG blowdown chemistry conditions or from a simulated condenser leak. This information will be used by operations personnel to evaluate the potential for SG tube corrosion in the crevice region. CHEMSOLV also calculates chemistry conditions throughout the steam-cycle system, as determined by the transport of volatile species such as ammonia, hydrazine, morpholine, and oxygen. A second model, SLUDGE, calculates the deposit loading in the SG as a function of time, based on concentrations of corrosion product in the final feedwater and plant operating conditions. Operations personnel can use this information to predict where to inspect and when to clean. In a future development, SLUDGE will track deposit loading arising from start-up crud bursts and will be used in conjunction with the thermohydraulics code, THIRST, to predict

  3. ChemCloud: Chemical e-Science Information Cloud

    OpenAIRE

    Todor, Alexandru; Paschke, Adrian; Heineke, Stephan

    2010-01-01

    Our Chemical e-Science Information Cloud (ChemCloud) - a Semantic Web based eScience infrastructure - integrates and automates a multitude of databases, tools and services in the domain of chemistry, pharmacy and bio-chemistry available at the Fachinformationszentrum Chemie (FIZ Chemie), at the Freie Universitaet Berlin (FUB), and on the public Web. Based on the approach of the W3C Linked Open Data initiative and the W3C Semantic Web technologies for ontologies and rules it semantically links...

  4. Molecular recognition of chem/biowarfare agents using micromechanical sensors

    Science.gov (United States)

    Ji, H.-F.; Yan, X.; Lu, Y.; Du, H.; Thundat, T.

    2006-05-01

    Recent terrorists events have shown that an urgent and widespread need exists for development of novel sensors for chemical and biowarfare agents. The advent of inexpensive, mass-produced microcantilever sensors, promises to bring about a revolution in detection of terrorists threats. Extremely sensitive chem/biosensors can be developed using microcantilever platform. Both frequency and bending of microcantilevers can be used to detect the chemical and biological species in air or solution. The specificity is achieved by immobilizing chemically-specific receptors the cantilever. This short report will give an overview of chemical/biological warfare agents sensor recently developed based on microcantilevers.

  5. Le concept d’éducation intégrale

    OpenAIRE

    Abega, Séverin Cécile; Langere-Menye, Gisèle

    2013-01-01

    EVA, Éducation à la Vie et à l’Amour, est un programme d’éducation intégrale de l’homme introduit dans les cycles primaire et secondaire de l’enseignement technique et de l’enseignement général au Cameroun. Mis en place depuis 1986, il mobilise les jeunes à partir de l’éducation sexuelle et de la prévention des MST/sida dans le but de faire changer leur comportement en conformité avec les grands axes de l’action mondiale et régionale, tout en tenant compte du contexte psychoaffectif, social, ...

  6. Jeunes du Mékong et intégration

    CERN Multimedia

    Jeunes du Mékong et intégration

    2010-01-01

    Marché d’artisanat du Vietnam de l’Association Jeunes du Mékong et Intégration. Le mardi 4 mai, nous serons dans le hall devant la cafeteria. Ce sera avec grand plaisir que nous vous proposerons nos différents produits du Vietnam en faveur des enfants défavorisés du Vietnam. Profitez de cette occasion pour faire vos petits, ou plus grands cadeaux pour la Fête des mères ! Nous vous présenterons les différents nouveaux projets soutenus par l’association dans des dossiers illustrés et vous aurez l’occasion de rencontrer notre chef de projet pour en discuter.  

  7. ChemCloud: Chemical e-Science Information Cloud

    CERN Document Server

    Todor, Alexandru; Heineke, Stephan

    2010-01-01

    Our Chemical e-Science Information Cloud (ChemCloud) - a Semantic Web based eScience infrastructure - integrates and automates a multitude of databases, tools and services in the domain of chemistry, pharmacy and bio-chemistry available at the Fachinformationszentrum Chemie (FIZ Chemie), at the Freie Universitaet Berlin (FUB), and on the public Web. Based on the approach of the W3C Linked Open Data initiative and the W3C Semantic Web technologies for ontologies and rules it semantically links and integrates knowledge from our W3C HCLS knowledge base hosted at the FUB, our multi-domain knowledge base DBpedia (Deutschland) implemented at FUB, which is extracted from Wikipedia (De) providing a public semantic resource for chemistry, and our well-established databases at FIZ Chemie such as ChemInform for organic reaction data, InfoTherm the leading source for thermophysical data, Chemisches Zentralblatt, the complete chemistry knowledge from 1830 to 1969, and ChemgaPedia the largest and most frequented e-Learning...

  8. ChemTok: A New Rule Based Tokenizer for Chemical Named Entity Recognition.

    Science.gov (United States)

    Akkasi, Abbas; Varoğlu, Ekrem; Dimililer, Nazife

    2016-01-01

    Named Entity Recognition (NER) from text constitutes the first step in many text mining applications. The most important preliminary step for NER systems using machine learning approaches is tokenization where raw text is segmented into tokens. This study proposes an enhanced rule based tokenizer, ChemTok, which utilizes rules extracted mainly from the train data set. The main novelty of ChemTok is the use of the extracted rules in order to merge the tokens split in the previous steps, thus producing longer and more discriminative tokens. ChemTok is compared to the tokenization methods utilized by ChemSpot and tmChem. Support Vector Machines and Conditional Random Fields are employed as the learning algorithms. The experimental results show that the classifiers trained on the output of ChemTok outperforms all classifiers trained on the output of the other two tokenizers in terms of classification performance, and the number of incorrectly segmented entities. PMID:26942193

  9. Hydrogen isotope MicroChemLab FY15.

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, David [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Luo, Weifang [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Stewart, Kenneth D. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)

    2015-09-01

    We have developed a new method to measure the composition of gaseous mixtures of any two hydrogen isotopes, as well as an inert gas component. When tritium is one of those hydrogen isotopes, there is usually some helium present, because the tritium decays to form helium at a rate of about 1% every 2 months. The usual way of measuring composition of these mixtures involves mass spectrometry, which involves bulky, energy-intensive, expensive instruments, including vacuum pumps that can quite undesirably disperse tritium. Our approach uses calorimetry of a small quantity of hydrogen-absorbing material to determine gas composition without consuming or dispersing the analytes. Our work was a proof of principle using a rather large and slow benchtop calorimeter. Incorporation of microfabricated calorimeters, such as those that have been developed in Sandia’s MicroChemLab program or that are now commercially available, would allow for faster measurements and a smaller instrument footprint.

  10. Second data release of the Kepler-INT Survey

    CERN Document Server

    Greiss, S; Gänsicke, B T; Martín, E L; Groot, P J; Irwin, M J; González-Solares, E; Greimel, R; Fusillo, N P Gentile; Still, M

    2012-01-01

    This short document reports on the second data release of the Kepler-INT Survey (KIS, Greiss et al. 2012). The Kepler field, a 116 sq.deg region of the Cygnus and Lyra constellations, is the target of the most intensive search for transiting planets to date. The Kepler mission provides superior time series photometry, with an enormous impact on all areas of stellar variability. The initial release catalogue (Greiss et al. 2012) concerned data taken between May and August 2011, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, H-alpha, reaching down to a limit of ~20th mag in the Vega system. Observations covering ~50 sq.deg passed our quality control thresholds and constituted the first data release. Here we report on the second data release, covering an additional ~63 sq.deg of the Kepler field. We apply the exact same quality control criteria and photometric calibration as in the initial release catalogue (see Greiss et a...

  11. Initial data release of the Kepler-INT Survey

    CERN Document Server

    Greiss, S; Steeghs, D T H; Martin, E L; Groot, P J; Irwin, M J; Gonzalez-Solares, E; Greimel, R; Knigge, C; Ostensen, R H; Verbeek, K; Drew, J E; Drake, J; Jonker, P G; Ripepi, V; Scaringi, S; Southworth, J; Still, M; Wright, N J

    2012-01-01

    This paper describes the first data release of the Kepler-INT Survey (KIS), that covers a 116 deg2 region of the Cygnus and Lyra constellations. The Kepler field is the target of the most intensive search for transiting planets to date. Despite the fact that the Kepler mission provides superior time series photometry, with an enormous impact on all areas of stellar variability, its field lacks optical photometry complete to the confusion limit of the Kepler instrument necessary for selecting various classes of targets. For this reason, we follow the observing strategy and data reduction method used in the IPHAS and UVEX galactic plane surveys in order to produce a deep optical survey of the Kepler field. This initial release concerns data taken between May and August 2011, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, H-alpha, reaching down to a limit of around 20th mag in the Vega system. Observations covering around 5...

  12. INITIAL DATA RELEASE OF THE KEPLER-INT SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Greiss, S.; Steeghs, D.; Gaensicke, B. T. [Department of Physics, Astronomy and Astrophysics group, University of Warwick, CV4 7AL Coventry (United Kingdom); Martin, E. L. [INTA-CSIC Centro de Astrobiologia, Carretera de Ajalvir km 4, 28550 Torrejon de Ardoz (Spain); Groot, P. J.; Verbeek, K.; Jonker, P. G.; Scaringi, S. [Department of Astrophysics/IMAPP, Radboud University Nijmegen, P.O. Box 9010, 6500 GL Nijmegen (Netherlands); Irwin, M. J.; Gonzalez-Solares, E. [Cambridge Astronomy Survey Unit, Institute of Astronomy, University of Cambridge, Madingley Road, CB3 0HA Cambridge (United Kingdom); Greimel, R. [Institut fuer Physik, Karl-Franzen Universitaet Graz, Universitaetsplatz 5, 8010 Graz (Austria); Knigge, C. [School of Physics and Astronomy, University of Southampton, Southampton, Hampshire SO17 1BJ (United Kingdom); Ostensen, R. H. [Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven (Belgium); Drew, J. E.; Farnhill, H. [Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom); Drake, J.; Wright, N. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Ripepi, V. [INAF-Osservatorio Astronomico di Capodimonte, via Moiariello 16, Naples I-80131 (Italy); Southworth, J. [Astrophysics Group, Keele University, Newcastle-under-Lyme ST5 5BG (United Kingdom); Still, M., E-mail: s.greiss@warwick.ac.uk [NASA Ames Research Center, M/S 244-40, Moffett Field, CA 94035 (United States); and others

    2012-07-15

    This paper describes the first data release of the Kepler-INT Survey (KIS) that covers a 116 deg{sup 2} region of the Cygnus and Lyra constellations. The Kepler field is the target of the most intensive search for transiting planets to date. Despite the fact that the Kepler mission provides superior time-series photometry, with an enormous impact on all areas of stellar variability, its field lacks optical photometry complete to the confusion limit of the Kepler instrument necessary for selecting various classes of targets. For this reason, we follow the observing strategy and data reduction method used in the IPHAS and UVEX galactic plane surveys in order to produce a deep optical survey of the Kepler field. This initial release concerns data taken between 2011 May and August, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, H{alpha}, reaching down to a 10{sigma} limit of {approx}20th mag in the Vega system. Observations covering {approx}50 deg{sup 2}, thus about half of the field, passed our quality control thresholds and constitute this first data release. We derive a global photometric calibration by placing the KIS magnitudes as close as possible to the Kepler Input Catalog (KIC) photometry. The initial data release catalog containing around 6 million sources from all the good photometric fields is available for download from the KIS Web site (www.astro.warwick.ac.uk/research/kis/) as well as via MAST (KIS magnitudes can be retrieved using the MAST enhanced target search page http://archive.stsci.edu/kepler/kepler{sub f}ov/search.php and also via Casjobs at MAST Web site http://mastweb.stsci.edu/kplrcasjobs/).

  13. INITIAL DATA RELEASE OF THE KEPLER-INT SURVEY

    International Nuclear Information System (INIS)

    This paper describes the first data release of the Kepler-INT Survey (KIS) that covers a 116 deg2 region of the Cygnus and Lyra constellations. The Kepler field is the target of the most intensive search for transiting planets to date. Despite the fact that the Kepler mission provides superior time-series photometry, with an enormous impact on all areas of stellar variability, its field lacks optical photometry complete to the confusion limit of the Kepler instrument necessary for selecting various classes of targets. For this reason, we follow the observing strategy and data reduction method used in the IPHAS and UVEX galactic plane surveys in order to produce a deep optical survey of the Kepler field. This initial release concerns data taken between 2011 May and August, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, Hα, reaching down to a 10σ limit of ∼20th mag in the Vega system. Observations covering ∼50 deg2, thus about half of the field, passed our quality control thresholds and constitute this first data release. We derive a global photometric calibration by placing the KIS magnitudes as close as possible to the Kepler Input Catalog (KIC) photometry. The initial data release catalog containing around 6 million sources from all the good photometric fields is available for download from the KIS Web site (www.astro.warwick.ac.uk/research/kis/) as well as via MAST (KIS magnitudes can be retrieved using the MAST enhanced target search page http://archive.stsci.edu/kepler/kepler_fov/search.php and also via Casjobs at MAST Web site http://mastweb.stsci.edu/kplrcasjobs/).

  14. Initial Data Release of the Kepler-INT Survey

    Science.gov (United States)

    Greiss, S.; Steeghs, D.; Gänsicke, B. T.; Martín, E. L.; Groot, P. J.; Irwin, M. J.; González-Solares, E.; Greimel, R.; Knigge, C.; Østensen, R. H.; Verbeek, K.; Drew, J. E.; Drake, J.; Jonker, P. G.; Ripepi, V.; Scaringi, S.; Southworth, J.; Still, M.; Wright, N. J.; Farnhill, H.; van Haaften, L. M.; Shah, S.

    2012-07-01

    This paper describes the first data release of the Kepler-INT Survey (KIS) that covers a 116 deg2 region of the Cygnus and Lyra constellations. The Kepler field is the target of the most intensive search for transiting planets to date. Despite the fact that the Kepler mission provides superior time-series photometry, with an enormous impact on all areas of stellar variability, its field lacks optical photometry complete to the confusion limit of the Kepler instrument necessary for selecting various classes of targets. For this reason, we follow the observing strategy and data reduction method used in the IPHAS and UVEX galactic plane surveys in order to produce a deep optical survey of the Kepler field. This initial release concerns data taken between 2011 May and August, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, Hα, reaching down to a 10σ limit of ~20th mag in the Vega system. Observations covering ~50 deg2, thus about half of the field, passed our quality control thresholds and constitute this first data release. We derive a global photometric calibration by placing the KIS magnitudes as close as possible to the Kepler Input Catalog (KIC) photometry. The initial data release catalog containing around 6 million sources from all the good photometric fields is available for download from the KIS Web site (www.astro.warwick.ac.uk/research/kis/) as well as via MAST (KIS magnitudes can be retrieved using the MAST enhanced target search page http://archive.stsci.edu/kepler/kepler_fov/search.php and also via Casjobs at MAST Web site http://mastweb.stsci.edu/kplrcasjobs/).

  15. ChemProt-3.0: a global chemical biology diseases mapping

    DEFF Research Database (Denmark)

    Kringelum, Jens Vindahl; Kjærulff, Sonny Kim; Brunak, Søren;

    2016-01-01

    ChemProt is a publicly available compilation of chemical-protein-disease annotation resources that enables the study of systems pharmacology for a small molecule across multiple layers of complexity from molecular to clinical levels. In this third version, ChemProt has been updated to more than 1...

  16. L'intégration de l'informatique à l'enseignement

    OpenAIRE

    Gomel, Janine

    1992-01-01

    Actuellement, dans le domaine de l'enseignement et de l'utilisation de l'informatique, nous parlons beaucoup d'intégration. De l'intégration des savoirs, de celle des disciplines et de celle de l'ordinateur à l'enseignement.Le Programme d'intégration de la micro-informatique à l'enseignement (PIME), programme d'enrichissement que le Ministère offre aux enseignants et aux conseillers pédagogiques, ainsi que « Le village Prologue », une expérience dans une école qui se vit et se multiplie au se...

  17. Rbpj conditional knockout reveals distinct functions of Notch4/Int3 in mammary gland development and tumorigenesis

    OpenAIRE

    Raafat, A.; Lawson, S; Bargo, S; Klauzinska, M; Strizzi, L; Goldhar, AS; Buono, K; Salomon, D.; Vonderhaar, BK; Callahan, R

    2008-01-01

    Transgenic mice expressing the Notch 4 intracellular domain (ICD) (Int3) in the mammary gland have two phenotypes: arrest of mammary alveolar/lobular development and mammary tumorigenesis. Notch4 signaling is mediated primarily through the interaction of Int3 with the transcription repressor/activator Rbpj. We have conditionally ablated the Rbpj gene in the mammary glands of mice expressing whey acidic protein (Wap)-Int3. Interestingly, Rbpj knockout mice (Wap-Cre+/Rbpj−/−/ Wap-Int3) have nor...

  18. NobleChemTM for commercial power plant application

    International Nuclear Information System (INIS)

    NoblechemTM is a GE patented technology that has been applied in 26 operating BWRs worldwide for potential IGSCC mitigation of reactor internal components, when used along with low levels of hydrogen in the feedwater. The technology demonstrates a method of utilizing hydrogen water chemistry (HWC) more effectively by using the extraordinary catalytic activity of noble metals to react hydrogen and oxygen. The addition of hydrogen gas to the feedwater of a BWR, was developed in the 1980's to mitigate the stress corrosion cracking propensity of BWR structural materials. The specification for HWC recommends establishing an electrochemical corrosion potential (ECP) of -230 mV(SHE) or less on the component of interest. Unfortunately, meeting this specification in BWR reactor internal components results in a significant increase in the radiation levels in the main steam. The accompanying operating dose rate is unacceptable for many utilities and thus moderate HWC (1 to 1.6 ppm hydrogen in the feedwater) has not been widely adapted. Unlike BWR structural materials, which only reach the ECP specification of -230 mV(SHE) at low bulk concentrations of reactor water oxidants (oxygen and hydrogen peroxide), noble metal treated surfaces respond to the molar ratio of hydrogen to total oxidants which is attained at very low hydrogen levels, with little or no long-term increase in main steam radiation levels. NoblechemTM takes advantage of this catalytic property by incorporating a thin deposit of platinum and rhodium on structural surfaces. This paper briefly describes the process of NobleChemTM application and the knowledge gained from the extensive experience from 26 BWRs over the past 5 years. (authors)

  19. La problématique des intérêts familiaux en droit public

    OpenAIRE

    Millard, Eric

    1996-01-01

    La notion d'intérêts familiaux n'est pas familière au juriste. En droit civil, on envisagera plus volontiers la question de l'intérêt de la famille, principalement pour déterminer sa compatibilité avec celui de l'enfant ; mais ces intérêts ne recouvrent en rien le sens que peuvent donner aux intérêts familiaux les acteurs des politiques familiales et plus généralement les historiens ou les sociologues qui les étudient. En droit public, la notion est négligée car elle n'est pas de l'actualité...

  20. ChemDoodle Web Components: HTML5 toolkit for chemical graphics, interfaces, and informatics

    OpenAIRE

    Burger, Melanie C

    2015-01-01

    ChemDoodle Web Components (abbreviated CWC, iChemLabs, LLC) is a light-weight (~340 KB) JavaScript/HTML5 toolkit for chemical graphics, structure editing, interfaces, and informatics based on the proprietary ChemDoodle desktop software. The library uses and WebGL technologies and other HTML5 features to provide solutions for creating chemistry-related applications for the web on desktop and mobile platforms. CWC can serve a broad range of scientific disciplines including crystallography, mat...

  1. ChemDoodle Web Components: HTML5 toolkit for chemical graphics, interfaces, and informatics.

    Science.gov (United States)

    Burger, Melanie C

    2015-01-01

    ChemDoodle Web Components (abbreviated CWC, iChemLabs, LLC) is a light-weight (~340 KB) JavaScript/HTML5 toolkit for chemical graphics, structure editing, interfaces, and informatics based on the proprietary ChemDoodle desktop software. The library uses and WebGL technologies and other HTML5 features to provide solutions for creating chemistry-related applications for the web on desktop and mobile platforms. CWC can serve a broad range of scientific disciplines including crystallography, materials science, organic and inorganic chemistry, biochemistry and chemical biology. CWC is freely available for in-house use and is open source (GPL v3) for all other uses.Graphical abstractAdd interactive 2D and 3D chemical sketchers, graphics, and spectra to websites and apps with ChemDoodle Web Components. PMID:26185528

  2. Photoinduced Electron Transfer in the Strong Coupling Regime: Waveguide-Plasmon Polaritons.

    Science.gov (United States)

    Zeng, Peng; Cadusch, Jasper; Chakraborty, Debadi; Smith, Trevor A; Roberts, Ann; Sader, John E; Davis, Timothy J; Gómez, Daniel E

    2016-04-13

    Reversible exchange of photons between a material and an optical cavity can lead to the formation of hybrid light-matter states where material properties such as the work function [ Hutchison et al. Adv. Mater. 2013 , 25 , 2481 - 2485 ], chemical reactivity [ Hutchison et al. Angew. Chem., Int. Ed. 2012 , 51 , 1592 - 1596 ], ultrafast energy relaxation [ Salomon et al. Angew. Chem., Int. Ed. 2009 , 48 , 8748 - 8751 ; Gomez et al. J. Phys. Chem. B 2013 , 117 , 4340 - 4346 ], and electrical conductivity [ Orgiu et al. Nat. Mater. 2015 , 14 , 1123 - 1129 ] of matter differ significantly to those of the same material in the absence of strong interactions with the electromagnetic fields. Here we show that strong light-matter coupling between confined photons on a semiconductor waveguide and localized plasmon resonances on metal nanowires modifies the efficiency of the photoinduced charge-transfer rate of plasmonic derived (hot) electrons into accepting states in the semiconductor material. Ultrafast spectroscopy measurements reveal a strong correlation between the amplitude of the transient signals, attributed to electrons residing in the semiconductor and the hybridization of waveguide and plasmon excitations. PMID:26963038

  3. AerChemMIP: Quantifying the effects of chemistry and aerosols in CMIP6

    OpenAIRE

    Collins, William J; Lamarque, Jean-François; Schulz, Michael; Boucher, Olivier; Eyring, Veronika; Hegglin, Michaela I.; Maycock, Amanda; Myhre, Gunnar; Prather, Michael; Shindell, Drew; Smith, Steven J.

    2016-01-01

    The Aerosol Chemistry Model Intercomparison Project (AerChemMIP) is endorsed by the Coupled-Model Intercomparison Project 6 (CMIP6) and is designed to quantify the climate and air quality impacts of aerosols and chemically-reactive gases. These are specifically near-term climate forcers (NTCFs: tropospheric ozone and aerosols, and their precursors), methane, nitrous oxide and ozone-depleting halocarbons. The aim of AerChemMIP is to answer four scientific questions: 1. How have anthropogeni...

  4. Biomimetic microfluidics – the key to revolutionising autonomous chem/bio-sensing platforms

    OpenAIRE

    Diamond, Dermot; Florea, Larisa; Dunne, Aishling; Tudor, Alexandru; Ben Azouz, Aymen; Coleman, Simon

    2015-01-01

    Imagine a world in which issues related to long-term (months to years) reliability of chem/bio-sensing platforms have been solved, and devices capable of carrying out complex chem/bio-functions in an autonomous manner are ubiquitously available. The potential impact of these technologies socially and economically is enormous, and the demand will be universal, driven by an infinite range of applications. Devices will perform complex analytical measurements while located in remote and environm...

  5. radEq Add-On Module for CFD Solver Loci-CHEM

    Science.gov (United States)

    McCloud, Peter

    2013-01-01

    Loci-CHEM to be applied to flow velocities where surface radiation due to heating from compression and friction becomes significant. The module adds a radiation equilibrium boundary condition to the computational fluid dynamics (CFD) code to produce accurate results. The module expanded the upper limit for accurate CFD solutions of Loci-CHEM from Mach 4 to Mach 10 based on Space Shuttle Orbiter Re-Entry trajectories. Loci-CHEM already has a very promising architecture and performance, but absence of radiation equilibrium boundary condition limited the application of Loci-CHEM to below Mach 4. The immediate advantage of the add-on module is that it allows Loci-CHEM to work with supersonic flows up to Mach 10. This transformed Loci-CHEM from a rocket engine- heritage CFD code with general subsonic and low-supersonic applications, to an aeroheating code with hypersonic applications. The follow-on advantage of the module is that it is a building block for additional add-on modules that will solve for the heating generated at Mach numbers higher than 10.

  6. Initial characterization of the Pf-Int recombinase from the malaria parasite Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Mehdi Ghorbal

    Full Text Available BACKGROUND: Genetic variation is an essential means of evolution and adaptation in many organisms in response to environmental change. Certain DNA alterations can be carried out by site-specific recombinases (SSRs that fall into two families: the serine and the tyrosine recombinases. SSRs are seldom found in eukaryotes. A gene homologous to a tyrosine site-specific recombinase has been identified in the genome of Plasmodium falciparum. The sequence is highly conserved among five other members of Plasmodia. METHODOLOGY/PRINCIPAL FINDINGS: The predicted open reading frame encodes for a ∼57 kDa protein containing a C-terminal domain including the putative tyrosine recombinase conserved active site residues R-H-R-(H/W-Y. The N-terminus has the typical alpha-helical bundle and potentially a mixed alpha-beta domain resembling that of λ-Int. Pf-Int mRNA is expressed differentially during the P. falciparum erythrocytic life stages, peaking in the schizont stage. Recombinant Pf-Int and affinity chromatography of DNA from genomic or synthetic origin were used to identify potential DNA targets after sequencing or micro-array hybridization. Interestingly, the sequences captured also included highly variable subtelomeric genes such as var, rif, and stevor sequences. Electrophoretic mobility shift assays with DNA were carried out to verify Pf-Int/DNA binding. Finally, Pf-Int knock-out parasites were created in order to investigate the biological role of Pf-Int. CONCLUSIONS/SIGNIFICANCE: Our data identify for the first time a malaria parasite gene with structural and functional features of recombinases. Pf-Int may bind to and alter DNA, either in a sequence specific or in a non-specific fashion, and may contribute to programmed or random DNA rearrangements. Pf-Int is the first molecular player identified with a potential role in genome plasticity in this pathogen. Finally, Pf-Int knock-out parasite is viable showing no detectable impact on blood stage

  7. Tight regulation of the intS gene of the KplE1 prophage: a new paradigm for integrase gene regulation.

    Directory of Open Access Journals (Sweden)

    Gaël Panis

    2010-10-01

    Full Text Available Temperate phages have the ability to maintain their genome in their host, a process called lysogeny. For most, passive replication of the phage genome relies on integration into the host's chromosome and becoming a prophage. Prophages remain silent in the absence of stress and replicate passively within their host genome. However, when stressful conditions occur, a prophage excises itself and resumes the viral cycle. Integration and excision of phage genomes are mediated by regulated site-specific recombination catalyzed by tyrosine and serine recombinases. In the KplE1 prophage, site-specific recombination is mediated by the IntS integrase and the TorI recombination directionality factor (RDF. We previously described a sub-family of temperate phages that is characterized by an unusual organization of the recombination module. Consequently, the attL recombination region overlaps with the integrase promoter, and the integrase and RDF genes do not share a common activated promoter upon lytic induction as in the lambda prophage. In this study, we show that the intS gene is tightly regulated by its own product as well as by the TorI RDF protein. In silico analysis revealed that overlap of the attL region with the integrase promoter is widely encountered in prophages present in prokaryotic genomes, suggesting a general occurrence of negatively autoregulated integrase genes. The prediction that these integrase genes are negatively autoregulated was biologically assessed by studying the regulation of several integrase genes from two different Escherichia coli strains. Our results suggest that the majority of tRNA-associated integrase genes in prokaryotic genomes could be autoregulated and that this might be correlated with the recombination efficiency as in KplE1. The consequences of this unprecedented regulation for excessive recombination are discussed.

  8. Apuntes sobre la fisionomía profesional de intérpretes

    OpenAIRE

    Klotchkov, Claudio

    2000-01-01

    Se cree, y con toda razón, que la competencia interpretativa abarca determinados conocimientos y determinadas habilidades individuales de la personalidad del intérprete. La interpretación no vale para cualquiera sino para personas con elevadas vocación y plasticidad comunicativas, lindantes con la dinámica del arte escénico. ¿Cuáles son las supuestas condiciones que un intérprete debe reunir? ¿Qué estrategias y tácticas del perfeccionamiento conductual ha de desplegar para estar a la altura d...

  9. L'intégration du cloud computing au sein d'une PME genevoise

    OpenAIRE

    Nkidiaka, Ndongala Brady; Leclere, Olivier

    2014-01-01

    Ce travail de Bachelor a pour but de servir de support aux PME genevoises qui veulent étudier la possibilité d’intégrer le Cloud Computing au sein de leurs locaux. Il est donc question des grandes problématiques liées à l’introduction du Cloud Computing en entreprise. Mon travail contient sept chapitres. Nous commencerons par les définitions du Cloud Computing et des PME. Puis nous nous intéresserons à l’organisation du Cloud Computing au sein de l’entreprise. Il s’agira, ici, de s’assurer de...

  10. Building the EarthChem System for Advanced Data Management in Igneous Geochemistry

    Science.gov (United States)

    Lehnert, K.; Walker, J. D.; Carlson, R. W.; Hofmann, A. W.; Sarbas, B.

    2004-12-01

    Several mature databases of geochemical analyses for igneous rocks are now available over the Internet. The existence of these databases has revolutionized access to data for researchers and students allowing them to extract data sets customized to their specific problem from global data compilations with their desktop computer within a few minutes. Three of the database efforts - PetDB, GEOROC, and NAVDAT - have initiated a collaborative effort called EarthChem to create better and more advanced and integrated data management for igneous geochemistry. The EarthChem web site (http://www.earthchem.org/) serves as a portal to the three databases and information related to EarthChem activities. EarthChem participants agreed to establish a dialog to minimize duplication of effort and share useful tools and approaches. To initiate this dialog, a workshop was run by EarthChem in October, 2003 to discuss cyberinfrastructure needs in igneous geochemistry (workshop report available at the EarthChem site). EarthChem ran an information booth with database and visualization demonstrations at the Fall 2003 AGU meeting (and will have one in 2004) and participated in the May 2003 GERM meeting in Lyon, France where we provided the newly established Publishers' Round Table a list of minimum standards of data reporting to ease the assimilation of data into the databases. Aspects of these suggestions already have been incorporated into new data policies at Geochimica et Cosmochimica Acta and Chemical Geology (Goldstein et al. 2004), and are under study by the Geological Society of America. EarthChem presented its objectives and activities to the Solid Earth Sciences community at the Annual GSA Meeting 2003 (Lehnert et al, 2003). Future plans for EarthChem include expanding the types and amounts of data available from a single portal, giving researchers, faculty, students, and the general public the ability to search, visualize, and download geochemical and geochronological data for a

  11. The Int-2/Fgf-3 oncogene product is secreted and associates with extracellular matrix: implications for cell transformation.

    OpenAIRE

    Kiefer, P; Peters, G.; Dickson, C

    1991-01-01

    NIH3T3 cells transformed by mouse Int-2/Fgf-3 cDNA express a series of Int-2-related products representing discrete stages of processing and glycosylation. We confirm that in at least two highly transformed clonal lines, Int-2 products acquire further modifications and are efficiently secreted into the culture medium. Secreted proteins become associated with the cell surface and extracellular matrix and can be displaced by addition of soluble glycosaminoglycans, specifically heparin, heparan ...

  12. New inorganic nanotube polymer nanocomposites: Improved thermal, mechanical and tribological properties in isotactic polypropylene incorporating INT-MoS2.

    OpenAIRE

    Naffakh Cherradi Hadi, Mohammed; Díez-Pascual, Ana M.; Remskar, Maja; Marco, Carlos

    2012-01-01

    Environmentally friendly molybdenum disulfide (INT-MoS2) inorganic nanotubes were introduced into an isotactic polypropylene (iPP) polymer matrix to generate novel nanocomposite materials through an advantageous melt-processing route. The effects of INT-MoS2 content on the thermal, mechanical and tribological properties were investigated. The incorporation of INT-MoS2 generates notable performance enhancements through reinforcement effects, highly efficient nucleation activity and excellent l...

  13. Inteligentný integrovaný železničný systém InteGrail

    OpenAIRE

    Bednárová, Miroslava

    2013-01-01

    The aim of this thesis is to introduce the intelligent integrated railway system InteGrail. The thesis is divided into three logical parts, of which the first deals with history and development of European railways in the chosen countries. The second part describes development of specific intelligent railway systems, from their beginnings to the last predecessor of InteGrail. The last part is focused on the system InteGrail, its contents, goals and outputs. In the conclusion the thesis assess...

  14. The MIntAct project—IntAct as a common curation platform for 11 molecular interaction databases

    OpenAIRE

    Orchard, Sandra; Ammari, Mais; Aranda, Bruno; Breuza, Lionel; Briganti, Leonardo; Broackes-Carter, Fiona; Campbell, Nancy H.; Chavali, Gayatri; Chen, Carol; del-Toro, Noemi; Duesbury, Margaret; Dumousseau, Marine; Galeota, Eugenia; Hinz, Ursula; Iannuccelli, Marta

    2013-01-01

    IntAct (freely available at http://www.ebi.ac.uk/intact) is an open-source, open data molecular interaction database populated by data either curated from the literature or from direct data depositions. IntAct has developed a sophisticated web-based curation tool, capable of supporting both IMEx- and MIMIx-level curation. This tool is now utilized by multiple additional curation teams, all of whom annotate data directly into the IntAct database. Members of the IntAct team supply appropriate l...

  15. Soil diversity and hydration as observed by ChemCam at Gale crater, Mars

    Science.gov (United States)

    Meslin, P.-Y.; Gasnault, O.; Forni, O.; Schroder, S.; Cousin, A.; Berger, G.; Clegg, S.M.; Lasue, J.; Maurice, S.; Sautter, V.; Le Mouélic, S.; Wiens, R.C.; Fabre, C.; Goetz, W.; Bish, D.L.; Mangold, N.; Ehlmann, B.; Lanza, N.; Harri, A.-M.; Anderson, Ryan Bradley; Rampe, E.; McConnochie, T.H.; Pinet, P.; Blaney, D.; Leveille; Archer, D.; Barraclough, B.; Bender, S.; Blake, D.; Blank, J.G.; Bridges, N.; Clark, B. C.; DeFlores, L.; Delapp, D.; Dromart, G.; Dyar, M.D.; Fisk, M. R.; Gondet, B.; Grotzinger, J.; Herkenhoff, K.; Johnson, J.; Lacour, J.-L.; Langevin, Y.; Leshin, L.; Lewin, E.; Madsen, M.B.; Melikechi, N.; Mezzacappa, Alissa; Mischna, M.A.; Moores, J.E.; Newsom, H.; Ollila, A.; Perez; Renno, N.; Sirven, J.B.; Tokar, R.; de la Torre, M.; d'Uston, L.; Vaniman, D.; Yingst, A.

    2013-01-01

    The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of widespread martian soils and is similar in composition to the martian dust. It possesses a ubiquitous hydrogen signature in ChemCam spectra, corresponding to the hydration of the amorphous phases found in the soil by the CheMin instrument. This hydration likely accounts for an important fraction of the global hydration of the surface seen by previous orbital measurements. ChemCam analyses did not reveal any significant exchange of water vapor between the regolith and the atmosphere. These observations provide constraints on the nature of the amorphous phases and their hydration.

  16. Air pollution forecasting by coupled atmosphere-fire model WRF and SFIRE with WRF-Chem

    CERN Document Server

    Kochanski, Adam K; Mandel, Jan; Clements, Craig B

    2013-01-01

    Atmospheric pollution regulations have emerged as a dominant obstacle to prescribed burns. Thus, forecasting the pollution caused by wildland fires has acquired high importance. WRF and SFIRE model wildland fire spread in a two-way interaction with the atmosphere. The surface heat flux from the fire causes strong updrafts, which in turn change the winds and affect the fire spread. Fire emissions, estimated from the burning organic matter, are inserted in every time step into WRF-Chem tracers at the lowest atmospheric layer. The buoyancy caused by the fire then naturally simulates plume dynamics, and the chemical transport in WRF-Chem provides a forecast of the pollution spread. We discuss the choice of wood burning models and compatible chemical transport models in WRF-Chem, and demonstrate the results on case studies.

  17. Les poules Sussex ont un intérêt pour l’agriculture biologique

    OpenAIRE

    Maurer, Veronika; Clerc, Maurice

    2010-01-01

    La Poule Sussex est avant tout intéressante pour les élevages avec vente directe. La recherche agronomique continue! Objectif = trouver des poules adaptées à une alimentation bio et autant que possible locale; engraisser les poussins mâles.

  18. On-line chemistry monitoring and diagnostics using SMART ChemWorks

    International Nuclear Information System (INIS)

    In 1999 EPRI began using its SMART ChemWorks system for real-time monitoring and diagnostics in nuclear power plants. To date there are about 100 plant years of experience with this system. The SMART ChemWorks system includes an integrated plant chemistry simulator and the output from this simulation is used in several interesting applications. The system automatically monitors and evaluates plant chemistry data in real time all the time. Users are notified of excursions, sensor problems and chemistry changes via email, pagers and web page alerts. This paper will discuss the implementation of this system, integration with chemistry and other plant monitors and how the use of this intelligent system is helping nuclear plants in the United States leverage the greatest amount of information about the condition of the plant from the minimum number of installed monitors. This system integrates ChemWorks, EPRI's successful family of chemistry codes with a plant's chemistry data management system (CDMS) and a real-time intelligence engine. SMART ChemWorks performs virtual sensing, identifies normal and upset conditions, and evaluates the consistency of on-line monitor and grab sample readings. The system also performs diagnostics to identify the cause of chemistry upsets using a virtual fingerprintingtechnique. SMART ChemWorks uses a patented technology that employs plant-specific data, analytical and artificial intelligence models to determine the chemical state of the steam cycle. The objective of SMART ChemWorks is to monitor chemistry 7 days per week/24 hours per day with minimal utility resources

  19. Calibrating the ChemCam LIBS for Carbonate Minerals on Mars

    Science.gov (United States)

    Wiens, Roger C.; Clegg, Samuel M.; Ollila, Ann M.; Barefield, James E.; Lanza, Nina; Newsom, Horton E.

    2009-01-01

    The ChemCam instrument suite on board the NASA Mars Science Laboratory (MSL) rover includes the first LIBS instrument for extraterrestrial applications. Here we examine carbonate minerals in a simulated martian environment using the LIDS technique in order to better understand the in situ signature of these materials on Mars. Both chemical composition and rock type are determined using multivariate analysis (MVA) techniques. Composition is confirmed using scanning electron microscopy (SEM) techniques. Our initial results suggest that ChemCam can recognize and differentiate between carbonate materials on Mars.

  20. Inclusion of biomass burning in WRF-Chem: impact of wildfires on weather forecasts

    OpenAIRE

    G. Grell; S. R. Freitas; M. Stuefer; Fast, J.

    2010-01-01

    A plume rise algorithm for wildfires was included in WRF-Chem, and applied to look at the impact of intense wildfires during the 2004 Alaska wildfire season on weather simulations using model resolutions of 10 km and 2 km. Biomass burning emissions were estimated using a biomass burning emissions model. In addition a 1-D time dependent cloud model was used online in WRF-Chem to estimate injection heights as well as the final emission rates. It was shown that with the inclusion of the i...

  1. Inclusion of biomass burning in WRF-Chem: impact of wildfires on weather forecasts

    OpenAIRE

    G. Grell; S. R. Freitas; M. Stuefer; Fast, J.

    2011-01-01

    A plume rise algorithm for wildfires was included in WRF-Chem, and applied to look at the impact of intense wildfires during the 2004 Alaska wildfire season on weather simulations using model resolutions of 10 km and 2 km. Biomass burning emissions were estimated using a biomass burning emissions model. In addition, a 1-D, time-dependent cloud model was used online in WRF-Chem to estimate injection heights as well as the vertical distribution of the emission rates. It was shown that with the ...

  2. ChemProt-2.0: visual navigation in a disease chemical biology database

    DEFF Research Database (Denmark)

    Kjærulff, Sonny Kim; Wich, Louis; Kringelum, Jens Vindahl;

    2013-01-01

    ChemProt-2.0 (http://www.cbs.dtu.dk/services/ChemProt-2.0) is a public available compilation of multiple chemical-protein annotation resources integrated with diseases and clinical outcomes information. The database has been updated to > 1.15 million compounds with 5.32 millions bioactivity...... proteins, which can help in the prediction of off-target effects. Finally, the database was integrated into a visual interface that enables navigation of the pharmacological space for small molecules. Filtering options were included in order to facilitate and to guide dynamic search of specific queries....

  3. Calcium Sulfate Characterized by ChemCam/Curiosity at Gale Crater, Mars

    Science.gov (United States)

    Nachon, M.; Clegg, S. N.; Mangold, N.; Schroeder, S.; Kah, L. C.; Dromart, G.; Ollila, A.; Johnson, J. R.; Oehler, D. Z.; Bridges, J. C.; LeMouelic, S.; Forni, O.; Wiens, R. C.; Rapin, W.; Anderson, R. B.; Blaney, D. L.; Bell, J. F. , III; Clark, B.; Cousin, A.; Dyar, M. D.; Ehlmann, B.; Fabre, C.; Gasnault, O.; Grotzinger, J.; Lasue, J.; Lewin, E.; Leveille, R.; McLennan, S.; Maurice, S.; Meslin, P.-Y.; Rice, M.; Squyres, S. W.; Stack, K.; Sumner, D. Y.; Vaniman, D.; Wellington, D.

    2014-01-01

    Onboard the Mars Science Laboratory (MSL) Curiosity rover, the ChemCam instrument consists of :(1) a Laser-Induced Breakdown Spectrometer (LIBS) for elemental analysis of the targets [1;2] and (2) a Remote Micro Imager (RMI), for the imaging context of laser analysis [3]. Within the Gale crater, Curiosity traveled from Bradbury Landing through the Rocknest region and into Yellowknife Bay (YB). In the latter, abundant light-toned fracture-fill material were seen [4;5]. ChemCam analysis demonstrate that those fracture fills consist of calcium sulfates [6].

  4. The MIntAct project--IntAct as a common curation platform for 11 molecular interaction databases.

    Science.gov (United States)

    Orchard, Sandra; Ammari, Mais; Aranda, Bruno; Breuza, Lionel; Briganti, Leonardo; Broackes-Carter, Fiona; Campbell, Nancy H; Chavali, Gayatri; Chen, Carol; del-Toro, Noemi; Duesbury, Margaret; Dumousseau, Marine; Galeota, Eugenia; Hinz, Ursula; Iannuccelli, Marta; Jagannathan, Sruthi; Jimenez, Rafael; Khadake, Jyoti; Lagreid, Astrid; Licata, Luana; Lovering, Ruth C; Meldal, Birgit; Melidoni, Anna N; Milagros, Mila; Peluso, Daniele; Perfetto, Livia; Porras, Pablo; Raghunath, Arathi; Ricard-Blum, Sylvie; Roechert, Bernd; Stutz, Andre; Tognolli, Michael; van Roey, Kim; Cesareni, Gianni; Hermjakob, Henning

    2014-01-01

    IntAct (freely available at http://www.ebi.ac.uk/intact) is an open-source, open data molecular interaction database populated by data either curated from the literature or from direct data depositions. IntAct has developed a sophisticated web-based curation tool, capable of supporting both IMEx- and MIMIx-level curation. This tool is now utilized by multiple additional curation teams, all of whom annotate data directly into the IntAct database. Members of the IntAct team supply appropriate levels of training, perform quality control on entries and take responsibility for long-term data maintenance. Recently, the MINT and IntAct databases decided to merge their separate efforts to make optimal use of limited developer resources and maximize the curation output. All data manually curated by the MINT curators have been moved into the IntAct database at EMBL-EBI and are merged with the existing IntAct dataset. Both IntAct and MINT are active contributors to the IMEx consortium (http://www.imexconsortium.org). PMID:24234451

  5. Introduction to the Spring 2014 ConfChem on the Flipped Classroom

    Science.gov (United States)

    Luker, Chris; Muzyka, Jennifer; Belford, Robert

    2015-01-01

    Students' active engagement is one of the most critical challenges to any successful learning environment. The blending of active engagement along with rich, meaningful content is necessary for chemical educators to re-examine the purpose of the chemistry classroom. The Spring 2014 ConfChem conference, Flipped Classroom, was held from May 9 to…

  6. ChemSession'09 - 6. Warsaw Seminar of the PhD Students in Chemistry - Abstracts

    International Nuclear Information System (INIS)

    Book of Abstracts contains short descriptions of presentations 3 lectures and 105 posters presented during ChemSession'09 - 6th Warsaw Seminar of the PhD Students in Chemistry. Several posters were devoted to the radiochemistry, radiochemical analysis, radiation chemistry and radiobiology. Some posters on the material science dealing with materials important to nuclear sciences can be also found

  7. The Virtual ChemLab Project: A Realistic and Sophisticated Simulation of Inorganic Qualitative Analysis

    Science.gov (United States)

    Woodfield, Brian F.; Catlin, Heidi R.; Waddoups, Gregory L.; Moore, Melissa S.; Swan, Richard; Bodily, Greg; Allen, Rob

    2004-01-01

    Virtual ChemLab project is an instructional laboratory involved in providing a practical experience by connecting the theory and laboratory practicals, teaching laboratory techniques and teaching the cognitive processes. This lab provides the students with the freedom to explore, repeat the procedures again, focuses on the underlying principles of…

  8. ChemSession'08 - 5. Warsaw Seminar of the PhD Students in Chemistry - Abstracts

    International Nuclear Information System (INIS)

    Book of Abstracts consists of short descriptions of presentations: 5 lectures and 127 posters presented during ChemSession'08 - 5th Warsaw Seminar of the PhD Students in Chemistry. Several posters were devoted to the radiochemistry, radiochemical analysis, radiation chemistry and radiobiology. Some posters on the material science dealing with materials important to nuclear sciences can be also found

  9. Industrial capability to chem-mill aluminum alloy 2219 in T-37 and T-87

    Science.gov (United States)

    Milewski, C., Jr.; Chen, K. C. S.

    1979-01-01

    Procedures and chemical baths were developed for chem-milling aluminum alloy 2219. Using a series of sample etchings, it was found that good etching results could be obtained by using 'white plastic for porcelain repair (toluol, xylol, and petroleum distillates)' on top of cellosolve acetate as resist coatings and ferric chloride as on etchant.

  10. The Text-mining based PubChem Bioassay neighboring analysis

    Directory of Open Access Journals (Sweden)

    Wang Yanli

    2010-11-01

    Full Text Available Abstract Background In recent years, the number of High Throughput Screening (HTS assays deposited in PubChem has grown quickly. As a result, the volume of both the structured information (i.e. molecular structure, bioactivities and the unstructured information (such as descriptions of bioassay experiments, has been increasing exponentially. As a result, it has become even more demanding and challenging to efficiently assemble the bioactivity data by mining the huge amount of information to identify and interpret the relationships among the diversified bioassay experiments. In this work, we propose a text-mining based approach for bioassay neighboring analysis from the unstructured text descriptions contained in the PubChem BioAssay database. Results The neighboring analysis is achieved by evaluating the cosine scores of each bioassay pair and fraction of overlaps among the human-curated neighbors. Our results from the cosine score distribution analysis and assay neighbor clustering analysis on all PubChem bioassays suggest that strong correlations among the bioassays can be identified from their conceptual relevance. A comparison with other existing assay neighboring methods suggests that the text-mining based bioassay neighboring approach provides meaningful linkages among the PubChem bioassays, and complements the existing methods by identifying additional relationships among the bioassay entries. Conclusions The text-mining based bioassay neighboring analysis is efficient for correlating bioassays and studying different aspects of a biological process, which are otherwise difficult to achieve by existing neighboring procedures due to the lack of specific annotations and structured information. It is suggested that the text-mining based bioassay neighboring analysis can be used as a standalone or as a complementary tool for the PubChem bioassay neighboring process to enable efficient integration of assay results and generate hypotheses for

  11. iNuc-PhysChem: a sequence-based predictor for identifying nucleosomes via physicochemical properties.

    Directory of Open Access Journals (Sweden)

    Wei Chen

    Full Text Available Nucleosome positioning has important roles in key cellular processes. Although intensive efforts have been made in this area, the rules defining nucleosome positioning is still elusive and debated. In this study, we carried out a systematic comparison among the profiles of twelve DNA physicochemical features between the nucleosomal and linker sequences in the Saccharomyces cerevisiae genome. We found that nucleosomal sequences have some position-specific physicochemical features, which can be used for in-depth studying nucleosomes. Meanwhile, a new predictor, called iNuc-PhysChem, was developed for identification of nucleosomal sequences by incorporating these physicochemical properties into a 1788-D (dimensional feature vector, which was further reduced to a 884-D vector via the IFS (incremental feature selection procedure to optimize the feature set. It was observed by a cross-validation test on a benchmark dataset that the overall success rate achieved by iNuc-PhysChem was over 96% in identifying nucleosomal or linker sequences. As a web-server, iNuc-PhysChem is freely accessible to the public at http://lin.uestc.edu.cn/server/iNuc-PhysChem. For the convenience of the vast majority of experimental scientists, a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated mathematics that were presented just for the integrity in developing the predictor. Meanwhile, for those who prefer to run predictions in their own computers, the predictor's code can be easily downloaded from the web-server. It is anticipated that iNuc-PhysChem may become a useful high throughput tool for both basic research and drug design.

  12. ChemInform Abstract: The Palladium-Catalyzed Aerobic Kinetic Resolution of Secondary Alcohols: Reaction Development, Scope, and Applications.

    KAUST Repository

    Ebner, David C.

    2010-03-30

    ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

  13. La victoire posthume du Haut Conseil à l’intégration

    OpenAIRE

    Kirszbaum, Thomas

    2015-01-01

    Tout en occultant les références à l’intégration, la réponse gouvernementale aux « événements de janvier » dessine une politique des valeurs conforme à la doctrine du Haut Conseil à l'intégration récemment disparu. En cherchant à renforcer le sentiment d’appartenance nationale et à restaurer une mixité urbaine censée favoriser l’assimilation des « valeurs de la République », cette politique cible tacitement de jeunes français descendants d’immigrés et résidant dans les quartiers populaires....

  14. Recent developments of InteCAST software and its applications on special castings

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    with the development of computer technology, foundry CAE technology has made rapid progress. Commercial software packages of casting process simulation, therefore, have become more and more practical. This paper introduces both the recent developments and some applications of InteCAST software, a commercial numerical simulation software package for foundry industry, with more than 120 customers all over the world. The function modules of InteCAST8.0 and some new techniques, such as uneven mesh technology for mold filling simulation and numerical mouse technology for data visualization, were introduced. Several applications on special castings such as investment casting, low pressure die casting, and high pressure die casting, were given. These applications showed that the software can help engineers to optimize casting process by forecasting casting defect.

  15. BioInt: an integrative biological object-oriented application framework and interpreter.

    Science.gov (United States)

    Desai, Sanket; Burra, Prasad

    2015-01-01

    BioInt, a biological programming application framework and interpreter, is an attempt to equip the researchers with seamless integration, efficient extraction and effortless analysis of the data from various biological databases and algorithms. Based on the type of biological data, algorithms and related functionalities, a biology-specific framework was developed which has nine modules. The modules are a compilation of numerous reusable BioADTs. This software ecosystem containing more than 450 biological objects underneath the interpreter makes it flexible, integrative and comprehensive. Similar to Python, BioInt eliminates the compilation and linking steps cutting the time significantly. The researcher can write the scripts using available BioADTs (following C++ syntax) and execute them interactively or use as a command line application. It has features that enable automation, extension of the framework with new/external BioADTs/libraries and deployment of complex work flows. PMID:26561020

  16. Mieux comprendre la notion d’intégration entre apprentissage et jeu

    OpenAIRE

    Szilas, Nicolas; Sutter Widmer, Denise Josiane

    2009-01-01

    Concrétiser le potentiel des jeux vidéos pour l'apprentissage, c'est peut-être avant tout répondre à des questions à la fois fondamentales et pratiques : comment intégrer le contenu d'apprentissage dans un jeu ? Comment, dans un jeu pédagogique, ne sacrifier ni le gameplay, ni la qualité pédagogique, ni les deux ? Pour cela, après une rapide analyse de deux jeux pédagogiques de qualité, nous proposons une analyse systémique/sémiotique des jeux pour disséquer le concept d'intégration jeu – app...

  17. IntDb: A comprehensive database for classified introns of saccharomyces & human

    OpenAIRE

    Mohanty, Subhalaxmi; Nizam, Amouda; Biswal, Monalisha

    2012-01-01

    Introns (intra-genic) are non-coding regions of several eukaryotic genes. However, their role in regulation of transcription, embryonic development, stimulate gene (HEG) is apparent in recent years. Thus current research focuses on mutation in introns and their influence in causing various diseases. Though many available intron databases like YIDB, IDB, ExInt, GISSD, FUGOID, etc. discusses on various aspects of introns but none of them have classified the introns where identification of start...

  18. Catalogue des ravageurs d'intérêt agricole de Nouvelle-Calédonie

    OpenAIRE

    Brun, Luc-Olivier; Chazeau, Jean

    1986-01-01

    Ce document à double entrée, zoologique et botanique, recense tous les ravageurs d'intérêt agricole (acariens, insectes, mollusques, vertébrés) signalés en Nouvelle-Calédonie (435 espèces), avec leurs plantes-hôtes, la source de l'information, et une documentation photographique importante. (Résumé d'auteur)

  19. Retraction notice to: Artificial intelligence in pharmaceutical product formulation: Neural computing [Chem. Ind. Chem. Eng. Q. 15(4 (2009 227-236

    Directory of Open Access Journals (Sweden)

    Ibrić Svetlana

    2011-01-01

    Full Text Available This article has been retracted at the request of the authors. The retraction has been made because the authors admitted that they took the text and rawings from the review article written by R. Rowe and E. Colbourn, Future Medicinal Chemistry 1(4 (2009 713-726, without their permission and even did not include this article in the list of references. One of the conditions of submission of a paper for publication are that authors confirm that their work is entirely originally written, someone else’s data and/or text are appropriately cited or quoted and permission has been obtained for use of copyrighted material from other sources. Therefore, the retracted article represents a severe improperly usage of the scientific publishing system. Apologies are offered to readers of the Chem. Ind. Chem. Eng. Q. that this abuse was not detected during the submission process.

    Link to the retracted article 10.2298/CICEQ0904227I

  20. Mw Spectroscopy Coupled with Ultrafast UV Laser Vaporization: {RIBOSE} Found in the Gas Phase

    Science.gov (United States)

    Cocinero, Emilio J.; Ecija, Patricia; Basterretxea, Francisco J.; Fernandez, Jose A.; Castano, Fernando; Lesarri, Alberto; Grabow, Jens-Uwe

    2012-06-01

    Sugars are aldoses or ketoses with multiple hydroxy groups which have been elusive to spectroscopic studies. Here we report a rotational study of the aldopentose ribose. According to any standard textbook aldopentoses can exhibit either linear forms, cyclic five-membered (furanose) structures or six-membered (pyranose) rings, occurring either as α- or β- anomers depending on the orientation of the hydroxy group at C-1 (anomeric carbon). β-Furanose is predominant in ribonucleosides, RNA, ATP and other biochemically relevant derivatives, but is β-furanose the native form also of free ribose? Recent condensed-phase X-ray and older NMR studies delivered conflicting results. In order to solve this question we conducted a microwave study on D-ribose that, owing to ultrafast UV laser vaporization, has become the first C-5 sugar observed with rotational resolution. The spectrum revealed six conformations of free ribose, preferentially adopting β-pyranose chairs as well as higher-energy α-pyranose forms. The method also allowed for unambiguous distinction between different orientations of the hydroxy groups, which stabilize the structures by cooperative hydrogen-bond networks. No evidence was observed of the α-/β-furanoses or linear forms found in the biochemical derivatives. i) D. Šišak, L. B. McCusker, G. Zandomeneghi, B. H. Meier, D. Bläser, R. Boese, W. B. Schweizer, R. Gylmour and J. D. Dunitz Angew. Chem. Int. Ed. 49, 4503, 2010. ii) W. Saenger Angew. Chem. Int. Ed. 49, 6487, 2010. i) M. Rudrum, and D. F. Shaw, J. Chem. Soc. 52, 1965. ii) R. U. Lemieux and J. D. Stevens Can. J. Chem. 44, 249, 1966. iii) E. Breitmaier and U. Hollstein Org. Magn. Reson. 8, 573, 1976. E. J. Cocinero, A. Lesarri, P. Écija, F. J. Basterretxea, J. U. Grabow, J. A. Fernández and F. Castaño Angew. Chem. Int. Ed. in press: DOI: 10.1002/anie.201107973, 2012.

  1. The semantics of Chemical Markup Language (CML for computational chemistry : CompChem

    Directory of Open Access Journals (Sweden)

    Phadungsukanan Weerapong

    2012-08-01

    Full Text Available Abstract This paper introduces a subdomain chemistry format for storing computational chemistry data called CompChem. It has been developed based on the design, concepts and methodologies of Chemical Markup Language (CML by adding computational chemistry semantics on top of the CML Schema. The format allows a wide range of ab initio quantum chemistry calculations of individual molecules to be stored. These calculations include, for example, single point energy calculation, molecular geometry optimization, and vibrational frequency analysis. The paper also describes the supporting infrastructure, such as processing software, dictionaries, validation tools and database repositories. In addition, some of the challenges and difficulties in developing common computational chemistry dictionaries are discussed. The uses of CompChem are illustrated by two practical applications.

  2. Modelling of uranyl nitrate and nitric acid extraction in diluted TBP using Chem-Unifac

    International Nuclear Information System (INIS)

    Chem-UNIFAC model is applied to TBP/dodecane/water/UO2(NO3)2 and TBP/dodecane/water/HNO3 systems, following our previous studies on TBP/diluent (alkane, HCCl3, CCl4) and TBP/diluent/water/salting out agent (same diluents) systems. New Chem-UNIFAC parameters for TBP/water pair are calculated and an unique set of parameters is proposed to describe the TBP/dodecane/water/UO2(NO3)2 system, for a wide range of TBP/diluent volume proportions (10%, 30%, 50%, 100%) and a wide range of uranyl nitrate aqueous concentration. Nitric acid and water extraction in TBP/dodecane/water/HNO3 is also calculated and an improvement is found in the description of the corresponding isotherms. (authors)

  3. Characterising Brazilian biomass burning emissions using WRF-Chem with MOSAIC sectional aerosol

    Directory of Open Access Journals (Sweden)

    S. Archer-Nicholls

    2015-03-01

    Full Text Available The South American Biomass Burning Analysis (SAMBBA field campaign took detailed in situ flight measurements of aerosol during the 2012 dry season to characterise biomass burning aerosol and improve understanding of its impacts on weather and climate. Developments have been made to the Weather Research and Forecast model with chemistry (WRF-Chem model to improve the representation of biomass burning aerosol in the region, by coupling a sectional aerosol scheme to the plume-rise parameterisation. Brazilian Biomass Burning Emissions Model (3BEM fire emissions are used, prepared using PREP-CHEM-SRC, and mapped to CBM-Z and MOSAIC species. Model results have been evaluated against remote sensing products, AERONET sites, and four case studies of flight measurements from the SAMBBA campaign. WRF-Chem predicted layers of elevated aerosol loadings (5–20 μg sm−3 of particulate organic matter at high altitude (6–8 km over tropical forest regions, while flight measurements showed a sharp decrease above 2–4 km altitude. This difference was attributed to the plume-rise parameterisation overestimating injection height. The 3BEM emissions product was modified using estimates of active fire size and burned area for the 2012 fire season, which reduced the fire size. The enhancement factor for fire emissions was increased from 1.3 to 5 to retain reasonable aerosol optical depths (AODs. The smaller fire size lowered the injection height of the emissions, but WRF-Chem still showed elevated aerosol loadings between 4–5 km altitude. Over eastern cerrado (savannah-like regions, both modelled and measured aerosol loadings decreased above approximately 4 km altitude. Compared with MODIS satellite data and AERONET sites, WRF-Chem represented AOD magnitude well (between 0.3–1.5 over western tropical forest fire regions in the first half of the campaign, but tended to over-predict them in the second half, when precipitation was more significant. Over eastern

  4. Managing the computational chemistry big data problem: the ioChem-BD platform.

    Science.gov (United States)

    Álvarez-Moreno, M; de Graaf, C; López, N; Maseras, F; Poblet, J M; Bo, C

    2015-01-26

    We present the ioChem-BD platform ( www.iochem-bd.org ) as a multiheaded tool aimed to manage large volumes of quantum chemistry results from a diverse group of already common simulation packages. The platform has an extensible structure. The key modules managing the main tasks are to (i) upload of output files from common computational chemistry packages, (ii) extract meaningful data from the results, and (iii) generate output summaries in user-friendly formats. A heavy use of the Chemical Mark-up Language (CML) is made in the intermediate files used by ioChem-BD. From them and using XSL techniques, we manipulate and transform such chemical data sets to fulfill researchers' needs in the form of HTML5 reports, supporting information, and other research media. PMID:25469626

  5. The Semantics of Chemical Markup Language (CML) for Computational Chemistry : CompChem

    OpenAIRE

    Phadungsukanan Weerapong; Kraft Markus; Townsend Joe A; Murray-Rust Peter

    2012-01-01

    Abstract This paper introduces a subdomain chemistry format for storing computational chemistry data called CompChem. It has been developed based on the design, concepts and methodologies of Chemical Markup Language (CML) by adding computational chemistry semantics on top of the CML Schema. The format allows a wide range of ab initio quantum chemistry calculations of individual molecules to be stored. These calculations include, for example, single point energy calculation, molecular geometr...

  6. ChemSession'11 - 8. Warsaw Seminar of the PhD Students in Chemistry - Abstracts

    International Nuclear Information System (INIS)

    Book of Abstracts contains short descriptions of presentations: 4 lectures, 1 communication and 149 posters presented during ChemSession'11 - 8th Warsaw Seminar of the PhD Students in Chemistry (Warsaw, 13.05.2011). Several posters were devoted to the radiochemistry, radiochemical analysis, radiation chemistry, application of the radionuclides and radiobiology. Some posters on the material science dealing with materials important to nuclear sciences can be also mentioned.

  7. ChemT, a software for building template-based 3D chemical libraries.

    OpenAIRE

    Abreu, Rui M. V.; Froufe, Hugo J. C.; Daniel, Pedro O.M.; Queiroz, Maria João R. P.; Ferreira, Isabel C. F. R.

    2010-01-01

    ln the modem drug discovery process vast quantities of compounds are generated and there is a need for bioinformatic tools to efficiently create, manage and examine huge chemical compound libraries. Severa! software tools for drawing and generating chemical compounds structures are available, but they usually lack options for automatic generation of custom-made focused chemicallibraries. We have implemented ChemT (Chemical Templates), a free software too! that automates the pro...

  8. Mixed waste treatment using the ChemChar thermolytic detoxification technique

    Energy Technology Data Exchange (ETDEWEB)

    Kuchynka, D. [Mirage Systems, Sunnyvale, CA (United States)

    1995-10-01

    The diversity of mixed waste matrices contained at Department of Energy sites that require treatment preclude a single, universal treatment technology capable of handling sludges, solids, heterogeneous debris, aqueous and organic liquids and soils. This report describes the ChemChar thermolytic detoxification process. The process is a thermal, chemically reductive technology that converts the organic portion of mixed wastes to a synthesis gas, while simultaneously absorbing volatile inorganics on a carbon-based char.

  9. ChemSession'10: 7. Warsaw Seminar of the PhD Students in Chemistry. Abstracts

    International Nuclear Information System (INIS)

    Book of Abstracts contains short descriptions of presentations 4 lectures and 151 posters presented during ChemSession'10 - 7th Warsaw Seminar of the PhD Students in Chemistry (Warsaw, 14.05.2010). Several posters were devoted to the radiochemistry, radiochemical analysis, radiation chemistry, application of the radionuclides and radiobiology. Some posters on the material science dealing with materials important to nuclear sciences can be also mentioned.

  10. Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx

    OpenAIRE

    Saide, P.E.; S. N. Spak; Carmichael, G R; M. A. Mena-Carrasco; Howell, S.; D. C. Leon; J. R. Snider; A. R. Bandy; J. L. Collett; Benedict, K. B.; Szoeke, S. P.; L. N. Hawkins; Allen, G.; Crawford, I; J. Crosier

    2011-01-01

    We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign-averaged longitud...

  11. Chemerin/ChemR23 signaling axis is involved in the endothelial protection by EATP channel opener iptakalim

    Institute of Scientific and Technical Information of China (English)

    Rui-jun ZHAO; Hai WANG

    2011-01-01

    Aim: To elucidate the modulation of the chemerin/ChemR23 axis by iptakalim-inducecl opening of K channels and to determine the role of the chemerin/ChemR23 axis in the iptakalim-mediated endothelial protection.Methods: Cultured rat aortic endothelial cells (RAECs) were used. Chemerin secretion and ChemR23 protein expression were investi- gated using Western blot analysis. The gene expression level of ChemR23 was examined with RT-PCR. In addition, the release of nitric oxide (NO) was measured with a nitric oxide assay.Results: Homocysteine, uric acid, high glucose, or oxidized low-density lipoprotein (ox-LDL) down-regulated the chemerin secretion and ChemR23 gene/protein expression in RAECs as a function of concentration and time, which was reversed by pretreatment with iptaka- lim (1-10 μmol/L). Moreover, these effects of iptakalim were abolished in the presence of the K channel antagonist glibenclamide (1 μmol/L). Both iptakalim and recombinant chemerin restored the impaired NO production in RAECs induced by uric acid, and the effects were abolished by anti-ChemR23 antibodies.Conclusion: Iptakalim via opening K channels enhanced the endothelial chemerin/ChemR23 axis and NO production, thus improving endothelial function.

  12. Effective fragment potential method in Q-CHEM: a guide for users and developers.

    Science.gov (United States)

    Ghosh, Debashree; Kosenkov, Dmytro; Vanovschi, Vitalii; Flick, Joanna; Kaliman, Ilya; Shao, Yihan; Gilbert, Andrew T B; Krylov, Anna I; Slipchenko, Lyudmila V

    2013-05-01

    A detailed description of the implementation of the effective fragment potential (EFP) method in the Q-CHEM electronic structure package is presented. The Q-CHEM implementation interfaces EFP with standard quantum mechanical (QM) methods such as Hartree-Fock, density functional theory, perturbation theory, and coupled-cluster methods, as well as with methods for electronically excited and open-shell species, for example, configuration interaction, time-dependent density functional theory, and equation-of-motion coupled-cluster models. In addition to the QM/EFP functionality, a "fragment-only" feature is also available (when the system is described by effective fragments only). To aid further developments of the EFP methodology, a detailed description of the C++ classes and EFP module's workflow is presented. The EFP input structure and EFP job options are described. To assist setting up and performing EFP calculations, a collection of Perl service scripts is provided. The precomputed EFP parameters for standard fragments such as common solvents are stored in Q-CHEM's auxiliary library; they can be easily invoked, similar to specifying standard basis sets. The instructions for generating user-defined EFP parameters are given. Fragments positions can be specified by their center of mass coordinates and Euler angles. The interface with the IQMOL and WEBMO software is also described. PMID:23319180

  13. Optimizing global CO concentrations and emissions based on DART/CAM-CHEM

    Science.gov (United States)

    Gaubert, B.; Arellano, A. F.; Barre, J.; Worden, H. M.; Emmons, L. K.; Wiedinmyer, C.; Anderson, J. L.; Deeter, M. N.; Mizzi, A. P.; Edwards, D. P.

    2014-12-01

    Atmospheric Carbon Monoxide (CO) is an important trace gas in tropospheric chemistry through its impact on the oxidizing capacity of the troposphere, as precursor of ozone, and as a good tracer of combustion from both anthropogenic sources and wildfires. We will investigate the potential of the assimilation of TERRA/MOPITT observations to constrain the regional to global CO budget using DART (Data assimilation Research Testbed) together with the global Community Atmospheric Model (CAM-Chem). DART/CAM-Chem is based on an ensemble adjustment Kalman filter (EAKF) framework which facilitates statistical estimation of error correlations between chemical states (CO and related species) and parameters (including sources) in the model using the ensemble statistics derived from dynamical and chemical perturbations in the model. Here, we estimate CO emissions within DART/CAM-Chem using a state augmentation approach where CO emissions are added to the CO state vector being analyzed. We compare these optimized emissions to estimates derived from a traditional Bayesian synthesis inversion using the CO analyses (assimilated CO states) as observational constraints. The spatio-temporal distribution of CO and other chemical species will be compared to profile measurements from aircraft and other satellite instruments (e.g., INTEX-B, ARCTAS).

  14. OrChem - An open source chemistry search engine for Oracle®

    Directory of Open Access Journals (Sweden)

    Rijnbeek Mark

    2009-10-01

    Full Text Available Abstract Background Registration, indexing and searching of chemical structures in relational databases is one of the core areas of cheminformatics. However, little detail has been published on the inner workings of search engines and their development has been mostly closed-source. We decided to develop an open source chemistry extension for Oracle, the de facto database platform in the commercial world. Results Here we present OrChem, an extension for the Oracle 11G database that adds registration and indexing of chemical structures to support fast substructure and similarity searching. The cheminformatics functionality is provided by the Chemistry Development Kit. OrChem provides similarity searching with response times in the order of seconds for databases with millions of compounds, depending on a given similarity cut-off. For substructure searching, it can make use of multiple processor cores on today's powerful database servers to provide fast response times in equally large data sets. Availability OrChem is free software and can be redistributed and/or modified under the terms of the GNU Lesser General Public License as published by the Free Software Foundation. All software is available via http://orchem.sourceforge.net.

  15. A CNES remote operations center for the MSL ChemCam instrument

    Energy Technology Data Exchange (ETDEWEB)

    Wiens, Roger C [Los Alamos National Laboratory; Lafaille, Vivian [CNES; Lorgny, Eric [CNES; Baroukh, Julien [CNES; Gaboriaud, Alain [CNES; Saccoccio, Muriel [CNES; Perez, Rene [CNES; Gasnault, Olivier [CNRS/CESR; Maurice, Sylvestre [CNRS/CESR; Blaney, Diana [JPL

    2010-01-01

    For the first time, a CNES remote operations center in Toulouse will be involved in the tactical operations of a Martian rover in order to operate the ChemCam science instrument in the framework of the NASA MSL (Mars Science Laboratory) mission in 2012. CNES/CESR and LANL have developed and delivered to JPL the ChemCam (Chemistry Camera) instrument located on the top of mast and in the body of the rover. This instrument incorporates a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI) for determining elemental compositions of rock targets or soil samples at remote distances from the rover (2-7 m). An agreement has been achieved for operating ChemCam, alternatively, from Toulouse (FR) and Los Alamos (NM, USA), through the JPL ground data system in Pasadena (CA, USA) for a complete Martian year (2 years on Earth). After a brief overview of the MSL mission, this paper presents the instrument, the mission operational system and JPL organization requirements for the scientific investigators (PI and Co-Is). This paper emphasizes innovations applied on the ground segment components and on the operational approach to satisfy the requirements and constraints due to these shared and distributed operations over the world.

  16. Investigation of variation of precipitation by the cloud seeding using WRF-CHEM model

    Science.gov (United States)

    Chae, S.; Lee, K.; Lee, C.; Ahn, K.; Choi, Y.

    2012-12-01

    Resent observational and numerical studies demonstrate a significant effect of aerosols on the amount of precipitation and its spatial distribution. Airborne cloud seeding experiments using the AgI particles have been carried out in Korea. The Weather Research Forecast model coupled with chemistry mechanism and aerosol modules (WRF-CHEM) is used to investigate the effects of the airborne cloud seeding on precipitation. The sensitivity tests (EXP 1, 2, and 3) of the WRF-CHEM were performed on the airborne cloud seeding experiments. EXP 1 is a control run from the original WRF model which has no aerosol effect. EXP 2 and EXP 3 are the WRF-CHEM simulations coupled with RADM2/MADE-SORGAM modules and CBMZ/MOSAIC modules, respectively. The AgI seeding was considered as an emission of primary PM2.5 in the simulations. The unspeciated primary PM2.5 are of 10000 μg/(m2s) at 0.5 km about the ground level to simulate the cloud seeding in both cases. The results of sensitivity experiments with the chemistry mechanism and aerosol schemes showed that for the six hours after the seeding, the accumulated amounts of precipitation increased about 14% for EXP 2 and 45% for EXP3, compared to EXP 1. Also, the simulations showed that the seeding brought initial precipitation time forward aerosol by 10 minutes.

  17. CHEM-PATH-TRACKER: An automated tool to analyze chemical motifs in molecular structures.

    Science.gov (United States)

    Ribeiro, João V; Cerqueira, N M F S A; Fernandes, Pedro A; Ramos, Maria J

    2014-07-01

    In this article, we propose a method for locating functionally relevant chemical motifs in protein structures. The chemical motifs can be a small group of residues or structure protein fragments with highly conserved properties that have important biological functions. However, the detection of chemical motifs is rather difficult because they often consist of a set of amino acid residues separated by long, variable regions, and they only come together to form a functional group when the protein is folded into its three-dimensional structure. Furthermore, the assemblage of these residues is often dependent on non-covalent interactions among the constituent amino acids that are difficult to detect or visualize. To simplify the analysis of these chemical motifs and give access to a generalized use for all users, we developed chem-path-tracker. This software is a VMD plug-in that allows the user to highlight and reveal potential chemical motifs requiring only a few selections. The analysis is based on atoms/residues pair distances applying a modified version of Dijkstra's algorithm, and it makes possible to monitor the distances of a large pathway, even during a molecular dynamics simulation. This tool turned out to be very useful, fast, and user-friendly in the performed tests. The chem-path-tracker package is distributed as an independent platform and can be found at http://www.fc.up.pt/PortoBioComp/database/doku.php?id=chem-path-tracker. PMID:24775806

  18. Benchmarking Ligand-Based Virtual High-Throughput Screening with the PubChem Database

    Directory of Open Access Journals (Sweden)

    Mariusz Butkiewicz

    2013-01-01

    Full Text Available With the rapidly increasing availability of High-Throughput Screening (HTS data in the public domain, such as the PubChem database, methods for ligand-based computer-aided drug discovery (LB-CADD have the potential to accelerate and reduce the cost of probe development and drug discovery efforts in academia. We assemble nine data sets from realistic HTS campaigns representing major families of drug target proteins for benchmarking LB-CADD methods. Each data set is public domain through PubChem and carefully collated through confirmation screens validating active compounds. These data sets provide the foundation for benchmarking a new cheminformatics framework BCL::ChemInfo, which is freely available for non-commercial use. Quantitative structure activity relationship (QSAR models are built using Artificial Neural Networks (ANNs, Support Vector Machines (SVMs, Decision Trees (DTs, and Kohonen networks (KNs. Problem-specific descriptor optimization protocols are assessed including Sequential Feature Forward Selection (SFFS and various information content measures. Measures of predictive power and confidence are evaluated through cross-validation, and a consensus prediction scheme is tested that combines orthogonal machine learning algorithms into a single predictor. Enrichments ranging from 15 to 101 for a TPR cutoff of 25% are observed.

  19. Theoretical description of circular dichroism in photoelectron angular distributions of randomly oriented chiral molecules after multi-photon photoionization

    CERN Document Server

    Goetz, R E; Nikoobakht, B; Berger, R; Koch, C P

    2016-01-01

    Photoelectron circular dichroism refers to the forward/backward asymmetry in the photoelectron angular distribution with respect to the propagation axis of circularly polarized light. It has recently been demonstrated in femtosecond multi-photon photoionization experiments with randomly oriented camphor and fenchone molecules [C. Lux et al., Angew. Chem. Int. Ed. 51, 5001 (2012);C. S. Lehmann et al., J. Chem. Phys. 139, 234307 (2013)]. A theoretical framework describing this process as (2+1) resonantly enhanced multi-photon ionization is constructed, which consists of two-photon photoselection from randomly oriented molecules and successive one-photon ionisation of the photoselected molecules. It combines perturbation theory for the light-matter interaction with ab initio calculations for the two-photon absorption and a single-center expansion of the photoelectron wavefunction in terms of hydrogenic continuum functions. It is verified that the model correctly reproduces the basic symmetry behavior expected un...

  20. IntCal13 and Marine13 Radiocarbon Age Calibration Curves 0–50,000 Years cal BP

    OpenAIRE

    Bard, Edouard; Bayliss, Alex; Beck, J. Warren; Blackwell, Paul G.; Bronk Ramsey, Christopher; Caitlin E. Buck; Cheng, Hai; Edwards, R. Lawrence; Friedrich, Michael; Grootes, Pieter M; Guilderson, Thomas P; Haflidason, Haflidi; Hajdas, Irka; Hatté, Christine; Heaton, Timothy J.

    2013-01-01

    The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from C-14 measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived from the data using the random walk model (RWM) used to generate IntCal09 and Marine09, which has been revised to account for additional uncertainties and error structures. The new curves were ratified at the 21st International Radiocarbon c...

  1. 支持向量机算法和软件ChemSVM介绍%Introduction to the algorithm of support vector machine and the software ChemSVM

    Institute of Scientific and Technical Information of China (English)

    陆文聪; 陈念贻; 叶晨洲; 李国正

    2002-01-01

    Vladimir N.Vapnik等提出的统计学习理论(statistical learning theory,简称SLT)和支持向量机(support vector machine,简称SVM)算法已取得令人鼓舞的研究成果.本文旨在对这一新理论和新算法的原理作一介绍,并展望这一计算机学界的新成果在化学化工领域的应用前景."ChemSVM"软件提供了通用的支持向量机算法,并将其与数据库、知识库、原子参数及其他数据挖掘方法有机地集成起来.

  2. Comment on: ``The hindered rotor density-of-states interpolation function'' [J. Chem. Phys. 106, 6675 (1997)] and ``The hindered rotor density- of-states'' [J. Chem. Phys. 108, 2314 (1998)

    Science.gov (United States)

    McClurg, Richard B.

    1999-10-01

    There has been some confusion regarding the various approximations for the hindered rotor partition function and its associated thermodynamic functions and density of states. This comment seeks to clarify the situation by comparing and contrasting the various functions, particularly with regard to the consistent use of reference energies. Only the tabular data of Pitzer and Gwinn [J. Chem. Phys. 10, 428 (1942)] and our analytic function [J. Chem. Phys. 106, 6675 (1997)] have consistent reference energies. The main contribution of our publication is the set of simple, asymptotically correct expressions for the thermodynamic functions. There are similar, but different approximations to the density of states given by Knyazev and co-workers [J. Phys. Chem. A 102, 3916 (1998)] and by me [J. Chem. Phys. 108, 1748 (1998)].

  3. L'intérêt économique des plantations agroforestières

    OpenAIRE

    Terreaux, J.P.; Chavet, M.

    2005-01-01

    / L'agroforesterie est un terme très général qui englobe entre autres toutes les pratiques culturales qui associent d'une part des arbres ou arbustes, et d'autre part des cultures annuelles. Cette pratique permet une meilleure valorisation de certaines ressources, partagées entre les deux cultures, comme l'eau ou la lumière. Mais un second intérêt de l'agroforesterie provient de l'interconnection entre les bénéfices à court terme procurés par les cultures annuelles et les profits à long terme...

  4. Pétrole russe et investisseurs étrangers : des intérêts convergents

    OpenAIRE

    Locatelli, Catherine

    2004-01-01

    La croissance de la production pétrolière russe depuis 2000 a renforcé l'intérêt des compagnies pétrolières internationales pour ce pays. Toutefois, les investissements internationaux dans ce secteur demeurent limités en raison de fortes contraintes institutionnelles, économiques et politiques. Trois facteurs sont plus précisément susceptibles d'expliquer cet état de fait. En premier lieu, les décisions d'investissements résultent de rapports de forces et de négociations complexes entre des a...

  5. Art et violence de masse. Dialogue avec Juan-Manuel Echavarria (version intégrale)

    OpenAIRE

    Nanteuil, Matthieu de

    2011-01-01

    Entretien avec Juan-Manuel Echavarria, photographe et artiste colombien, à propos du rapport entre son oeuvre et la violence qui déchire la Colombie depuis des décennies. "Ce qui m’intéresse, aujourd’hui, à travers ma photographie, c’est de sortir de cette enceinte de quatre murs que forme mon studio de Bogotá pour me rendre dans la campagne colombienne, cette campagne frappée par une violence inimaginable et depuis si longtemps. Il n’y a sans doute pas d’autres façons de connaître notre réal...

  6. Campylobacter jejuni induces diverse kinetics and profiles of cytokine genes in INT-407 cells

    International Nuclear Information System (INIS)

    Objective was to examine the kinetic ability of embryonic human epithelial INT-407 cells to express messenger ribonucleic acid (mRNA) for various cytokines and chemokines in response to Campylobacter jejuni (C. jejuni) stimulation. In an experimental single-blind study, cultured embryonic human epithelial INT-407 cells were treated with different concentrations of viable C. jejuni, its sonicated and filtered supernatant. A modified non-radioactive in situ hybridization using probe cocktails was used to measure mRNA levels for the pro-inflammatory cytokines interleukin (IL)-1beta, IL-6, interferon-gamma, tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta1 and IL-8 and the anti-inflammatory cytokines, IL-4 and IL-10. The study was carried out from September 2005 to March 2007 at the Department of Microbiology, Immunology and Infectious Diseases, College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain. Viable C. jejuni sonicated bacteria and filtered supernatant induced high mRNA expression for the pro-inflammatory cytokines IL-1 beta, IL-6, IFN-gama, TNF-alpha, TGF-beta and IL-8 which peaked at the 12 hours post stimulation. Anti-inflammatory cytokine IL-4 and IL-10 mNRA expression were induced maximally at 3 hours post stimulation mainly by sonicated bacteria and filtrated supernatant, however, not with living bacteria and filtrated supernatant, however, not with living bacteria. Untreated embryonic human epithelial INT-407 cells expressed low amount of mNRA for the various cytokines and chemokines at all time points. For each cytokine, 4 samples were used per time hour. This study demonstrated that embryonic human epithelial INT-407 cells in response to viable C. jejuni or its cytotxins can alter cytokine and chemokine mNRA expression patterns and kinetics suggesting a potential role for these mediators in the immunopathogenesis of the infection caused by this pathogen, which might be relevant for future immunotherapeutic

  7. Réflexions sur l'intégration des TICS en EPS

    OpenAIRE

    Morieux, Marc; Thivent, Bernard; Denis, Gil

    2000-01-01

    Si l'intégration des Technologies de l'Information et de la Communication (TIC) en EPS (éducation physique et sportive) participe d'un mouvement général de l'ensemble des disciplines d'enseignement, ce mouvement nous semble présenter dans notre discipline des spécificités que nous souhaitons expliquer dans ce document. Les enseignants d'EPS utilisent parfois, pour les enseignements qu'ils dispensent, des outils (camescope, cardiofréquencemètre 1, micro-ordinateur...) que la technologie met à ...

  8. MOŽNOST IZGRADNJE MALE VETRNE ELEKTRARNE NA ŽITNEM SILOSU INTES

    OpenAIRE

    Knuplež, Matjaž

    2012-01-01

    Diplomsko delo obravnava možnost izgradnje male vetrne elektrarne na žitnem silosu Intes v Mariboru. V začetnih poglavjih diplomskega dela so predstavljeni zgodovina vetrnih elektrarn, meteorološki pogoji in energija vetra. Prikazani sta prirast hitrosti vetra z višino in hrapavost okolice za predvideno lokacijo. Predstavljene so razmere in stanje na področju obnovljivih virov v Sloveniji. Obravnavane so tudi različne vrste in izvedbe vetrnih turbin. Podane so karakteristike izbrane vetr...

  9. Intégration des moyens de paiement non bancaires sur Internet

    OpenAIRE

    Abdellaoui, Refka

    2012-01-01

    Le commerce électronique actuel en Europe est essentiellement bancaire et s’articule autour des moyens de paiement traditionnels : carte bancaire, chèque, virement, etc. Cependant, avec l’apparition de nouvelles technologies et l’évolution des règlementations, on a vu émerger progressivement de nouveaux moyens de paiement ainsi que le développement de plusieurs canaux de paiement sur Internet. Au cours de cette thèse, nous nous sommes intéressés donc aux nouveaux moyens de paiement et à leur ...

  10. A practical view of SMART ChemWorks, an online diagnostic monitoring system, after 150 plant years of experience

    International Nuclear Information System (INIS)

    The foundation of SMART ChemWorks is based on EPRI's ChemWorks family of codes, specifically on MULTEQ and the Plant Chemistry Simulators. SMART ChemWorks integrates a plant's chemistry data management system (CDMS) and a realtime intelligence engine to perform virtual sensing, identify normal and upset conditions, and evaluate the consistency of on-line monitor and grab sample readings. The system also performs diagnostics to identify the cause of chemistry upsets using a virtual fingerprintingtechnique. SMART ChemWorks uses a patented technology that employs plant-specific data, analytical and artificial intelligence models to determine the chemical state of the steam cycle. The objective of SMART ChemWorks is to monitor chemistry 7 days per week/24 hours per day with minimal utility resources. After 150 plant years of experience in using SMART ChemWorks, the system has proven to be a reliable method of identifying the early signs of abnormal chemistry conditions. As we move into the future, online monitoring diagnostic systems will continue to improve the safe and smooth operation of nuclear power plants. In addition, plant personnel are also finding SMART ChemWorks to be a useful means to achieve work destruction, allowing them to eliminate tasks from personal workloads. Not only can SMART ChemWorks create more free time in the day for plant personnel to focus attention on more essential tasks, but it can also reduce expenses. Through the optimization of sampling and calibration of instruments, plants will be able to reduce costs for related materials

  11. The integrator complex subunit 6 (Ints6 confines the dorsal organizer in vertebrate embryogenesis.

    Directory of Open Access Journals (Sweden)

    Lee D Kapp

    2013-10-01

    Full Text Available Dorsoventral patterning of the embryonic axis relies upon the mutual antagonism of competing signaling pathways to establish a balance between ventralizing BMP signaling and dorsal cell fate specification mediated by the organizer. In zebrafish, the initial embryo-wide domain of BMP signaling is refined into a morphogenetic gradient following activation dorsally of a maternal Wnt pathway. The accumulation of β-catenin in nuclei on the dorsal side of the embryo then leads to repression of BMP signaling dorsally and the induction of dorsal cell fates mediated by Nodal and FGF signaling. A separate Wnt pathway operates zygotically via Wnt8a to limit dorsal cell fate specification and maintain the expression of ventralizing genes in ventrolateral domains. We have isolated a recessive dorsalizing maternal-effect mutation disrupting the gene encoding Integrator Complex Subunit 6 (Ints6. Due to widespread de-repression of dorsal organizer genes, embryos from mutant mothers fail to maintain expression of BMP ligands, fail to fully express vox and ved, two mediators of Wnt8a, display delayed cell movements during gastrulation, and severe dorsalization. Consistent with radial dorsalization, affected embryos display multiple independent axial domains along with ectopic dorsal forerunner cells. Limiting Nodal signaling or restoring BMP signaling restores wild-type patterning to affected embryos. Our results are consistent with a novel role for Ints6 in restricting the vertebrate organizer to a dorsal domain in embryonic patterning.

  12. Entre a pedagogia legisladora e as pedagogias intérpretes

    Directory of Open Access Journals (Sweden)

    VIVIANE CASTRO CAMOZZATO

    2015-01-01

    Full Text Available Con base en las metáforas del legislador (asociado a la modernidad e intérprete (asociado a la posmodernidad discutidas por Zygmunt Bauman, este artículo problematiza algunos de los embates en torno a los significados de la pedagogía, intentando mostrar las inversiones para legislar a partir de ella y, también, la operación de interpretar con las pedagogías. El lema central se encuentra en el hecho de que las formas de demarcar, definir, cercar el concepto de pedagogía, se relaciona con una voluntad que es la de legislar sobre la sociedad y sus individuos. Con las fecundas transformaciones que han reconfigurado la sociedad y el estado de la cultura, se argumenta que ha habido una necesidad de que la pedagogía se adecuara a estas reconfiguraciones, actuando como intérprete de la cultura –lo que proporcionó, por su vez, la pluralidad del concepto de pedagogía y de las intenciones que la cruzan.

  13. Science-Technology-Society (STS) and ChemCom Courses Versus College Chemistry Courses: Is There a Mismatch?

    Science.gov (United States)

    Sanger, Michael J.; Greenbowe, Thomas J.

    1996-06-01

    This opinion paper poses questions for the chemical education community to consider about the nature of college chemistry courses and the expected student prerequisites. It also explores the basis for a potential mismatch that may exist for students enrolled in a traditional college chemistry course who have had Science-Technology-Society (STS) or ChemCom courses as their only prior high school chemistry courses. Even though ChemCom and STS courses are not designed to prepare students for traditional college chemistry courses for science and engineering majors, there has been an increase in the number of ChemCom and STS students enrolling in these courses. As background, the general teaching approach of ChemCom and STS courses is discussed in terms of the behaviorist, cognitive, and constructivist learning theories. This article addresses the advantages and disadvantages of high school chemistry courses based on ChemCom and reviews the chemical education research comparing the effectiveness of ChemCom courses to traditional high school chemistry courses. The authors concluded that more research comparing the effect of these instructional methods on both traditional and alternative assessments is warranted.

  14. Public Domain HTS Fingerprints: Design and Evaluation of Compound Bioactivity Profiles from PubChem's Bioassay Repository.

    Science.gov (United States)

    Helal, Kazi Yasin; Maciejewski, Mateusz; Gregori-Puigjané, Elisabet; Glick, Meir; Wassermann, Anne Mai

    2016-02-22

    Molecular profiling efforts aim at characterizing the biological actions of small molecules by screening them in hundreds of different biochemical and/or cell-based assays. Together, these assays yield a rich data landscape of target-based and phenotypic effects of the tested compounds. However, submitting an entire compound library to a molecular profiling panel can easily become cost-prohibitive. Here, we make use of historical screening assays to create comprehensive bioactivity profiles for more than 300 000 small molecules. These bioactivity profiles, termed PubChem high-throughput screening fingerprints (PubChem HTSFPs), report small molecule activities in 243 different PubChem bioassays. Although the assays originate from originally independently pursued drug or probe discovery projects, we demonstrate their value as molecular signatures when used in combination. We use these PubChem HTSFPs as molecular descriptors in hit expansion experiments for 33 different targets and phenotypes, showing that, on average, they lead to 27 times as many hits in a set of 1000 chosen molecules as a random screening subset of the same size (average ROC score: 0.82). Moreover, we demonstrate that PubChem HTSFPs retrieve hits that are structurally diverse and distinct from active compounds retrieved by chemical similarity-based hit expansion methods. PubChem HTSFPs are made freely available for the chemical biology research community. PMID:26898267

  15. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

  16. Chemical Response of CESM/CAM-Chem to MOPITT CO Ensemble-based Chemical Data Assimilation

    Science.gov (United States)

    Gaubert, B.; Arellano, A. F.; Barré, J.; Worden, H. M.; Emmons, L. K.; Tilmes, S.; Buchholz, R. R.; Wiedinmyer, C.; Vitt, F.; Anderson, J. L.; Deeter, M. N.; Edwards, D. P.

    2015-12-01

    Carbon Monoxide is a key component in tropospheric chemistry. It plays an important role by affecting the oxidative capacity through its reaction with OH and being a precursor of tropospheric ozone. One year of multispectral retrievals of CO partial columns obtained from the MOPITT instrument have been assimilated into the Community Atmosphere Model with Chemistry (CAM-Chem). The assimilation is carried out using an Ensemble Adjustment Kalman Filter algorithm within the Data Assimilation Research Testbed (DART) package. Two assimilation experiments have been performed: 1) assimilation of meteorological observations and 2) joint assimilation of meteorological observations and MOPITT CO. We first evaluate the assimilation performance by investigating skill scores and other statistics for the two experiments, and comparing to independent CO datasets such as surface (WDCGG), aircraft (MOZAIC-IAGOS), and FTS (NDACC). Our results clearly demonstrate an overall improvement for spatio-temporal magnitude and variability in representing CO abundance in CAM-Chem. We then investigate the response of CAM-Chem to changes in CO fields (via CO assimilation) focusing mainly on the oxidative capacity (i.e., OH distribution, methane lifetime) and CO chemical production and loss (i.e., regional to global budget). This is carried out by analyzing the mean 6-hourly forecast adjustments as reflected between the two experiments. We show that changes in CO directly impact OH abundance, with subsequent non-linear responses in CO chemical production (CO from methane and VOCs) and CO loss. This is clearly evident in NOx-limited regions (e.g., Southern Hemisphere, remote sites). Such analysis has direct implications on the consistencies in inverse modeling estimates of CO sources through improved representation of chemical response (including full chemistry) in atmospheric chemistry models and through multi-species constraints.

  17. Application of distance correction to ChemCam laser-induced breakdown spectroscopy measurements

    Science.gov (United States)

    Mezzacappa, A.; Melikechi, N.; Cousin, A.; Wiens, R. C.; Lasue, J.; Clegg, S. M.; Tokar, R.; Bender, S.; Lanza, N. L.; Maurice, S.; Berger, G.; Forni, O.; Gasnault, O.; Dyar, M. D.; Boucher, T.; Lewin, E.; Fabre, C.

    2016-06-01

    Laser-induced breakdown spectroscopy (LIBS) provides chemical information from atomic, ionic, and molecular emissions from which geochemical composition can be deciphered. Analysis of LIBS spectra in cases where targets are observed at different distances, as is the case for the ChemCam instrument on the Mars rover Curiosity, which performs analyses at distances between 2 and 7.4 m is not a simple task. In our previous work we showed that spectral distance correction based on a proxy spectroscopic standard created from first-shot dust observations on Mars targets ameliorates the distance bias in multivariate-based elemental-composition predictions of laboratory data. In this work, we correct an expanded set of neutral and ionic spectral emissions for distance bias in the ChemCam data set. By using and testing different selection criteria to generate multiple proxy standards, we find a correction that minimizes the difference in spectral intensity measured at two different distances and increases spectral reproducibility. When the quantitative performance of distance correction is assessed, there is improvement for SiO2, Al2O3, CaO, FeOT, Na2O, K2O, that is, for most of the major rock forming elements, and for the total major-element weight percent predicted. However, for MgO the method does not provide improvements while for TiO2, it yields inconsistent results. In addition, we have observed that many emission lines do not behave consistently with distance, evidenced from laboratory analogue measurements and ChemCam data. This limits the effectiveness of the method.

  18. Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx

    Science.gov (United States)

    Saide, P. E.; Spak, S. N.; Carmichael, G. R.; Mena-Carrasco, M. A.; Howell, S.; Leon, D. C.; Snider, J. R.; Bandy, A. R.; Collett, J. L.; Benedict, K. B.; de Szoeke, S. P.; Hawkins, L. N.; Allen, G.; Crawford, I.; Crosier, J.; Springston, S. R.

    2011-11-01

    We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign-averaged longitudinal gradients, and highlight differences in model simulations with (W) and without wet (NW) deposition processes. The higher aerosol loadings in the NW case produce considerable changes in MBL dynamics and cloud microphysics, in accordance with the established conceptual model of aerosol indirect effects. These include increase in cloud albedo, increase in MBL and cloud heights, drizzle suppression, increase in liquid water content, and increase in cloud lifetime. Moreover, better statistical representation of aerosol mass and number concentration improves model fidelity in reproducing observed spatial and temporal variability in cloud properties, including top and base height, droplet concentration, water content, rain rate, optical depth (COD) and liquid water path (LWP). Together, these help to quantify confidence in WRF-Chem's modeled aerosol-cloud interactions, while identifying structural and parametric uncertainties including: irreversibility in rain wet removal; overestimation of marine DMS and sea salt emissions and accelerated aqueous sulfate conversion. Our findings suggest that WRF-Chem simulates marine cloud-aerosol interactions at a level sufficient for applications in forecasting weather and air quality and studying aerosol climate forcing, including the reliability required for policy analysis and geo-engineering applications.

  19. Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx

    Energy Technology Data Exchange (ETDEWEB)

    Saide, Pablo; Spak, S. N.; Carmichael, Gregory; Mena-Carrasco, M. A.; Yang, Qing; Howell, S. G.; Leon, Dolislager; Snider, Jefferson R.; Bandy, Alan R.; Collett, Jeffrey L.; Benedict, K. B.; de Szoeke, S.; Hawkins, Lisa; Allen, Grant; Crawford, I.; Crosier, J.; Springston, S. R.

    2012-03-30

    We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign averaged longitudinal gradients, and highlight differences in model simulations with (W) and without wet (NW) deposition processes. The higher aerosol loadings in the NW case produce considerable changes in MBL dynamics and cloud microphysics, in accordance with the established conceptual model of aerosol indirect effects. These include increase in cloud albedo, increase in MBL and cloud heights, drizzle suppression, increase in liquid water content, and increase in cloud lifetime. Moreover, better statistical representation of aerosol mass and number concentration improves model fidelity in reproducing observed spatial and temporal variability in cloud properties, including top and base height, droplet concentration, water content, rain rate, optical depth (COD) and liquid water path (LWP). Together, these help to quantify confidence in WRF-Chem's modeled aerosol-cloud interactions, while identifying structural and parametric uncertainties including: irreversibility in rain wet removal; overestimation of marine DMS and sea salt emissions and accelerated aqueous sulfate conversion. Our findings suggest that WRF-Chem simulates marine cloud-aerosol interactions at a level sufficient for applications in forecasting weather and air quality and studying aerosol climate forcing, including the reliability required for policy analysis and geo-engineering applications.

  20. Effects on Student Achievement in General Chemistry Following Participation in an Online Preparatory Course. ChemPrep, a Voluntary, Self-Paced, Online Introduction to Chemistry

    Science.gov (United States)

    Botch, Beatrice; Day, Roberta; Vining, William; Stewart, Barbara; Rath, Kenneth; Peterfreund, Alan; Hart, David

    2007-03-01

    ChemPrep was developed to be a stand-alone preparatory short-course to help students succeed in general chemistry. It is Web-based and delivered using the OWL system. Students reported that the ChemPrep materials (short information pages, parameterized questions with detailed feedback, tutorials, and answers to questions through the OWL message system) permitted them to work independently without the need for textbook or lecture. On average, students who completed ChemPrep had higher grades in the subsequent GenChem, Nursing, and Honors chemistry courses, with a greater percentage achieving a grade of C- or higher. Participation in ChemPrep was voluntary, and more women than men responded. Students in the Honors course enrolled in ChemPrep in higher percentages than students in GenChem and Nursing. SAT and departmental math placement exam scores were used as proxy measures of prior achievement and ability. Based on these, Honors chemistry ChemPrep users were on par with their peers but performed better in the course than non-users. In GenChem and Nursing chemistry courses, ChemPrep helped students of high prior achievement and ability perform better than their achievement scores would predict. Weaker or less motivated students did not respond to the voluntary offerings of ChemPrep in the same numbers as stronger or more motivated students, and we are seeking alternate ways to reach this population.

  1. ChemCam passive reflectance spectroscopy of surface materials at the Curiosity landing site, Mars

    Science.gov (United States)

    Johnson, Jeffrey R.; Bell, J. F.; Bender, S.; Blaney, D.; Cloutis, E.; DeFlores, L.; Ehlmann, B.; Gasnault, O.; Gondet, B.; Kinch, K.; Lemmon, M.; Le Mouélic, S.; Maurice, S.; Rice, M.; Wiens, R. C.

    2015-03-01

    The spectrometers on the Mars Science Laboratory (MSL) ChemCam instrument were used in passive mode to record visible/near-infrared (400-840 nm) radiance from the martian surface. Using the onboard ChemCam calibration targets' housing as a reflectance standard, we developed methods to collect, calibrate, and reduce radiance observations to relative reflectance. Such measurements accurately reproduce the known reflectance spectra of other calibration targets on the rover, and represent the highest spatial resolution (0.65 mrad) and spectral sampling (visible/near-infrared reflectance spectra from a landed platform on Mars. Relative reflectance spectra of surface rocks and soils match those from orbital observations and multispectral data from the MSL Mastcam camera. Preliminary analyses of the band depths, spectral slopes, and reflectance ratios of the more than 2000 spectra taken during the first year of MSL operations demonstrate at least six spectral classes of materials distinguished by variations in ferrous and ferric components. Initial comparisons of ChemCam spectra to laboratory spectra of minerals and Mars analog materials demonstrate similarities with palagonitic soils and indications of orthopyroxene in some dark rocks. Magnesium-rich "raised ridges" tend to exhibit distinct near-infrared slopes. The ferric absorption downturn typically found for martian materials at rocks and drill tailings, consistent with their more ferrous nature. Calcium-sulfate veins exhibit the highest relative reflectances observed, but are still relatively red owing to the effects of residual dust. Such dust is overall less prominent on rocks sampled within the "blast zone" immediately surrounding the landing site. These samples were likely affected by the landing thrusters, which partially removed the ubiquitous dust coatings. Increased dust coatings on the calibration targets during the first year of the mission were documented by the ChemCam passive measurements as well

  2. A highly sensitive, integrable, multimode, interferometric, evanescent-wave chem/bio sensor

    Science.gov (United States)

    Lillie, Jeffrey J.

    A fully integrated optical chem/bio sensor complete with integrated source, chemically sensitive waveguide, detector arrays, and associated signal processing electronics on a Si-CMOS chip is a challenging, but highly desirable goal. An evanescent-wave multimode interferometric sensing element is a sensitive method for sensing, which is easily integrated on Si-CMOS. This work is concerned with the design, analysis, and demonstration of a planar multimode interferometric chem/bio sensor that is compatible with the fabrication constraints of Si-CMOS. A 4000-micron-long interferometric that can be adapted for different agents by a particular sensing layer has been fabricated on silicon using silicon dioxide and silicon oxynitride. Hexaflouro-isopropanol substituted polynorbornene is the sensing layer. This sensor has also been fabricated on a Si-CMOS circuit with embedded photodetectors. A sensor on silicon was demonstrated with a minimum detectable index change of 2.0x10 -6 using an accurate gas delivery system and a custom hermetic waveguide test chamber. A modal pattern analysis strategy has also been developed to extract the optimal SNR from the measured modal patterns. An understanding of the noise processes and spatial bandwidth effects has enabled an experimentally-based prediction of the index sensitivity of a fully integrated multimode chem/bio sensor on Si-CMOS at 9.2x10-7. Theoretically, the sensitivity enhancement of high over low index sensing layers and transverse-magnetic over transverse electric modes is described. Also, the sensitivity enhancement of higher-order-transverse modes has been quantified. The wide-angle beam propagation method has been used to simulate the sensor. This simulation showed the relation between the modal pattern repetition period and sensor sensitivity. Further, the modal coupling properties of the multimode y-junction have been described. A second multimode y-junction has been designed to change the modal excitation under the

  3. Chem2Bio2RDF: A Linked Open Data Portal for Chemical Biology

    CERN Document Server

    Chen, Bin; Zhu, Qian; Ding, Ying; Dong, Xiao; Sankaranarayanan, Madhuvanthi; Wang, Huijun; Sun, Yuyin

    2010-01-01

    The Chem2Bio2RDF portal is a Linked Open Data (LOD) portal for systems chemical biology aiming for facilitating drug discovery. It converts around 25 different datasets on genes, compounds, drugs, pathways, side effects, diseases, and MEDLINE/PubMed documents into RDF triples and links them to other LOD bubbles, such as Bio2RDF, LODD and DBPedia. The portal is based on D2R server and provides a SPARQL endpoint, but adds on few unique features like RDF faceted browser, user-friendly SPARQL query generator, MEDLINE/PubMed cross validation service, and Cytoscape visualization plugin. Three use cases demonstrate the functionality and usability of this portal.

  4. Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model

    International Nuclear Information System (INIS)

    China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35–50% of THg concentration and 50–70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. - Highlights: • China's anthropogenic mercury emission was 643.1 t in 2007. • GEOS-Chem model well reproduces the background Hg concentrations. • Anthropogenic emissions contribute 35–50% of Hg concentrations in polluted regions. • The priorities for mercury control in polluted regions are identified. - Anthropogenic Hg emissions are updated and their impacts on atmospheric mercury concentrations and depositions are quantified for China

  5. The Potassic Sedimentary Rocks in Gale Crater, Mars, as Seen by ChemCam Onboard Curiosity.

    Science.gov (United States)

    Le Deit, Laetitia; Mangold, Nicolas; Forni, Olivier; Cousin, Agnes; Lasue, Jeremie; Schröder, Susanne; Wiens, Roger C.; Sumner, Dawn Y.; Fabre, Cecile; Stack, Katherine M.; Anderson, Ryan; Blaney, Diana L.; Clegg, Samuel M.; Dromart, Gilles; Fisk, Martin; Gasnault, Olivier; Grotzinger, John P.; Gupta, Sanjeev; Lanza, Nina; Le Mouélic, Stephane; Maurice, Sylvestre; McLennan, Scott M.; Meslin, Pierre-Yves; Nachon, Marion; Newsom, Horton E.; Payre, Valerie; Rapin, William; Rice, Melissa; Sautter, Violaine; Treiman, Alan H.

    2016-01-01

    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters-thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system (Grotzinger et al., 2015). From ChemCam LIBS chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than five times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e. mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  6. Simulation of Extractive Distillation for Recycling Tetrahydrofuran from Pharmaceutical Wastewater with Chem CAD Software

    Directory of Open Access Journals (Sweden)

    Xiaoguang Wang

    2013-05-01

    Full Text Available The functions and application of ChemCAD simulation software was introduced. Mathematical model of extraction distillation process was established. The extractive distillation process for preparation of tetrahydrofuran (THF was simulated by SCDS rectification model in ChemCAD software, methanol-THF-solution and ethanedol-lithium chloride solution as extractant. Influence of extraction agent on vapor-liquid equilibrium curve of methanol-THF system and effects of theoretical plate number, feed and extractant input positions, extraction agent ratio (m(chlorinated lithium: v(ethanediol, extractant ratio (m (extractant: m(feed and reflux ratio on tower top mass fraction of THF were investigated. The results of simulation were compared with experimental data. Under optimum extraction distillation conditions: theoretical plate 30, extractant plate 6, feed plate 18, extraction agent ratio 0.24g/mL, extractant ratio 2.7 and reflux ratio 5.0, mass fraction of THF on tower top can reach 97.2%. The distribution characteristic parameters of the column were simulated. The results of simulation and experimental data agree satisfactorily.

  7. L’animal cobaye : un corps sans intériorité ?

    OpenAIRE

    Rémy, Catherine

    2010-01-01

    L’article soumet l’idée d’une représentation occidentale « naturaliste » des animaux – à savoir des corps sans intériorité – à l’épreuve du déroulement d’une activité concrète, l’expérimentation animale. Cette dernière est apparue au XIXe siècle et s’est construite sur l’idée d’une dichotomie corps/esprit renvoyant les animaux à une pure corporéité. À partir d’une enquête de terrain dans un laboratoire de physiologie animale appliquée à l’homme, il s’agit de suivre le traitement concret du co...

  8. Current status of the ParInt package for parallel multivariate integration

    International Nuclear Information System (INIS)

    The ParInt project focuses on the development of parallel algorithms and software for the computation of multi-variate integrals. We will give an overview of the contents and capabilities of the package. Our objective has been to provide the end-user with state of the art problem solving power. This has required work in a number of areas, including the fundamental numerical techniques, strategies for parallelization, user interfaces for general use and specific applications, and visualization of computations to analyze the mutual influences of problem characteristics and algorithm behavior. Furthermore, the integration of all the above into a versatile set of tools is aimed toward an efficient use of the available parallel or distributed computer resources. (author)

  9. Conception d'Antenne Spirale intégrée sur SOI à 60 GHz

    OpenAIRE

    Barakat, Moussa; Delaveaud, Christophe; Dussopt, Laurent; Ndagijimana, Fabien

    2009-01-01

    La conception d'une antenne spirale intégrée sur SOI est décrite. L'impact de la structure d'alimentation de l'antenne spirale à double brin sur le coefficient de réflexion et le rapport axial est analysé. Un bon coefficient de réflexion avec une bande passante de 35 GHz à -10 dB et une bonne polarisation circulaire couvrant une intervalle d'angle élévation de 120° indépendamment de l'angle d'azimut sont obtenus. L'efficacité de rayonnement simulée est de 80 % avec un gain simulé de 4.3 dBi....

  10. Green Key Miljömärkning - Verkliga inbesparingar eller inte

    OpenAIRE

    Spennert, Tom

    2015-01-01

    Syftet med examensarbetet är att undersöka om logianläggningar (hotell) i Finland och Sverige som låtit sig miljömärkas med Green Key miljömärkningen gjort verkliga inbesparingar eller inte. Avsikten är även ta reda på om dessa logianläggningar har fått andra fördelar genom miljömärkningen. Delsyftet med arbetet är att redogöra för kriterierna gällande Gren Key miljömärkningen för logianläggningar (hotell) på Åland 2015. I studien redogörs också kort för några andra miljömärkningar som...

  11. Mongolie intérieure. Désertification, migration et transformation des modes de vie

    OpenAIRE

    Zhang, Qian

    2013-01-01

    En Mongolie intérieure, le gouvernement chinois a engagé la lutte contre la désertification des steppes et la dégradation des terres. Depuis une dizaine d’années, il encourage la migration et la sédentarisation des éleveurs nomades en milieu urbain. Sur le terrain, si les subventions de l’État poussent certains à partir en laissant derrière eux leurs terres, d’autres restent profondément attachés à leur mode de vie. Mais les méthodes traditionnelles de gestion de l’espace, comme la transhuman...

  12. Bloddonation : Icke bloddonatorers skäl till att inte donera blod

    OpenAIRE

    Jansson, Anna; Ungermann, Ines

    2013-01-01

    Inledning: Sjukvården är beroende av frivilliga bloddonatorer. Det behövs alltid fler bloddonatorer då vi med dagens sjukvård kan utföra alltmer avancerad kirurgi samt rädda och hjälpa allt fler sjuka samt skadade, med hjälp av blod från frivilliga donatorer. Syfte: Syftet var att undersöka vilka skäl som anges till att inte donera blod, samt undersöka om viljan att ge blod skiljer sig beroende på kön, ålder och om man har yrkes- eller studieanknytning till sjukvård. Syftet var också att unde...

  13. Intégration et collaboration dans l'entreprise en réseau

    OpenAIRE

    Neubert, Gilles

    2009-01-01

    La façon d'organiser le travail, d'une part au sein des entreprises, et d'autre part entre les différentes entreprises, est un enjeu central dans la recherche de l'efficacité et de la performance. Dans les années 90 l'arrivée des progiciels de gestion intégrés a favorisé l'émergence d'une rationalité globale de l'entreprise, mais leur valeur ajoutée s'appuie en grande partie sur un alignement organisationnel de l'entreprise. Cette transformation s'est accompagnée d'un mouvement de spécialisat...

  14. Intérêt de la PCR dans le diagnostic de la trypanosomiase humaine africaine

    OpenAIRE

    Simo, G.; Grébaut, Pascal; Herder, Stéphane; Nkinin, S.W.; Penchenier, Laurent

    1999-01-01

    Dans le but de montrer l'intérêt de la PCR ("Polymerase Chain Reaction") sur sang dans le diagnostic de la Trypanosomiase Humaine Africaine (T.H.A.), du sang a été collecté dans des tubes EDTA ("Ethylène Diamine Tétra Acétate) chez 1.663 personnes dont 1.614 provenant de 3 foyers actifs de la T.H.A. (Bipindi, Campo et Fontem) au Cameroun et 49 chez des individus (Européens) non exposés à la maladie du sommeil. Les examens parasitologiques et la culture in vitro ont revélé 62 trypanosomés. La ...

  15. Actionneur linéaire intégré pour application domotique

    OpenAIRE

    Ben Ahmed, Hamid; Multon, Bernard; Prevond, Laurent; Lucidarme, Jean

    2000-01-01

    National audience D'une manière générale, les entraînements électriques pour la domotique requièrent une grande discrétion aussi bien sonore que visuelle (et donc une forte intégration dans leur environnement), un faible coût et enfin une fiabilité élevée tant au niveau du fonctionnement que de celui de la sécurité des personnes (normes d'isolation électrique). D'autre part, Ces entraînements ne sont appelés à fonctionner que quelques minutes par jour. De ce fait, le rendement énergétique ...

  16. L’Islamisme marocain : entre révolution et intégration

    OpenAIRE

    Dialmy, Abdessamad

    2009-01-01

    Défini comme un déviationnisme par le pouvoir politique en raison de son opposition de nature religieuse, l’islamisme marocain est-il condamné à rester toujours l’Autre, cette inquiétante étrangeté ? Son éclatement entre radicalisme révolutionnaire et institutionnalisation réformiste n’est-il pas la prémisse de son intégration partielle au jeu politique ? L’accès au statut de parti lui étant interdit, le passage du statut de mouvement islamiste violent à celui d’association culturelle légalis...

  17. SI-COTS : Aide à l'intégration de COTS Products

    OpenAIRE

    Roose, Philippe

    2009-01-01

    Workshop MADSI (Méthodes avancées de développement des systèmes d'information) - 25ème congrès INFORSID Ca papier présente un système d'information permettant d'aider la sélection de COTS Product. Nous présentons une définition de ce qu'est un COTS Product, le système d'information avec les exigences requises pour une intégration efficace et enfin un outil permettant aux développeurs de vérifier la sélection et de réaliser les prototypes nécessaires.

  18. La ansiedad escénica en intérpretes musicales chilenos

    Directory of Open Access Journals (Sweden)

    Mimí Marinovic

    2006-06-01

    Full Text Available La ansiedad escénica (AE es uno de los mayores problemas del ejercicio profesional de los intérpretes musicales. Encuestas realizadas en países desarrollados revelan cifras de prevalencia entre 24% -70% y citan casos severos, causantes del abandono de la carrera. Objetivos: detectar la prevalencia de la AE en músicos chilenos que desempeñan su profesión en los principales conjuntos de música de concierto y determinar algunos de los factores que, a su juicio, influyen en su aparición. Método: 249 intérpretes (122 instrumentistas, 26 directores y 101 cantantes respondieron un cuestionario autoaplicado, incluido en una investigación más amplia sobre los intérpretes de arte. Este instrumento fue complementado con 36 entrevistas abiertas (13 instrumentistas, 6 directores y 11 cantantes. Resultados: el 78% de los músicos estudiados admitió haber sufrido AE, más mujeres que varones. El 64% consideró que ella se relaciona principalmente con la tarea a ejecutar (preparación insuficiente, dificultad de la obra, mientras que el 32% lo atribuyó a factores personales (ser nervioso, temor al fracaso y sólo el 4% a factores situacionales. Hubo diferencias significativas por género, especialidad y edad. Las entrevistas permitieron profundizar acerca del alcance de estos resultados. Conclusiones: se constató una alta prevalencia de AE, la cual debiera ser abordada interdisciplinariamente por especialistas de la salud mental y la música en beneficio de la educación general, la formación especializada y el desarrollo profesional de los intérpretes musicalesPerformance anxiety (PA is one of the major problems that musicians face in their careers. Surveys carried out in developed countries show prevalence figures ranging 24% -70% and quote severe cases leading to abandonment of the profession. Objectives: detect the prevalence of PA in Chilean musicians working in the main groups of concert music and determine some of the factors that

  19. Den som inte finns : Att vara kille med ätstörningsberoende

    OpenAIRE

    Svensson, Linda; Friman, Amelie

    2016-01-01

    Ätstörningar är en sjukdom som drabbar både tjejer och killar. Det framkommer i artiklarna att det finns en felaktig bild av att killar inte drabbas av psykiska sjukdomar såsom ätstörningar. Då ätstörningar hos killar är ett dolt problem fokuserar detta arbete på att beskriva hur det är att vara kille med ätstörningsberoende. Metoden är en systematisk litteraturöversikt där tolv vetenskapliga artiklar inom området ”killar med ätstörningsberoende” kvalitetsgranskades och analyserades. Utifrån...

  20. PubChem3D: Shape compatibility filtering using molecular shape quadrupoles

    Directory of Open Access Journals (Sweden)

    Kim Sunghwan

    2011-07-01

    Full Text Available Abstract Background PubChem provides a 3-D neighboring relationship, which involves finding the maximal shape overlap between two static compound 3-D conformations, a computationally intensive step. It is highly desirable to avoid this overlap computation, especially if it can be determined with certainty that a conformer pair cannot meet the criteria to be a 3-D neighbor. As such, PubChem employs a series of pre-filters, based on the concept of volume, to remove approximately 65% of all conformer neighbor pairs prior to shape overlap optimization. Given that molecular volume, a somewhat vague concept, is rather effective, it leads one to wonder: can the existing PubChem 3-D neighboring relationship, which consists of billions of shape similar conformer pairs from tens of millions of unique small molecules, be used to identify additional shape descriptor relationships? Or, put more specifically, can one place an upper bound on shape similarity using other "fuzzy" shape-like concepts like length, width, and height? Results Using a basis set of 4.18 billion 3-D neighbor pairs identified from single conformer per compound neighboring of 17.1 million molecules, shape descriptors were computed for all conformers. These steric shape descriptors included several forms of molecular volume and shape quadrupoles, which essentially embody the length, width, and height of a conformer. For a given 3-D neighbor conformer pair, the volume and each quadrupole component (Qx, Qy, and Qz were binned and their frequency of occurrence was examined. Per molecular volume type, this effectively produced three different maps, one per quadrupole component (Qx, Qy, and Qz, of allowed values for the similarity metric, shape Tanimoto (ST ≥ 0.8. The efficiency of these relationships (in terms of true positive, true negative, false positive and false negative as a function of ST threshold was determined in a test run of 13.2 billion conformer pairs not previously considered

  1. IntApop: a web service for predicting apoptotic protein interactions in humans.

    Science.gov (United States)

    Zhou, Nan; Zhang, Jinchun; Feng, Ling; Lu, Bangmin; Wang, Zijie; Sun, Rong; Wu, Chuanfang; Bao, Jinku

    2013-12-01

    Apoptosis, a type of cell death, is necessary for maintaining tissue homeostasis and removing malignant cells. Interrupted apoptosis process contributes to carcinogenesis, developmental defects, autoimmune diseases and neurological disorders. Due to the complexity of the process, the molecular dynamics and relative interactions of individual proteins responsible for the activation or inhibition of apoptosis should be researched systematically. In this study, we integrate known protein interactions from databases DIP, IntAct, MINT, HPRD and BioGRID by Naïve Bayes classifier. The receiver operation characteristic (ROC) curve with the area under the ROC curve (AUC) of 0.797 indicates it has a good performance in prediction. Then, we predict the global human apoptotic protein interactions network. Within it, we not only identify the already known interactions of caspases (caspase-8/-10, caspase-9, caspase-3/-6/-7) and Bcl-2 family, but also reveal that Bid can interact with casein kinases (CSK21/22/2B, KC1A, KC1E); both of B2LA1 and B2CL2 can interact with Bid, Bax and Bak; caspase-8 interacts with autophagic proteins (MLP3B, MLP3A and LRRk2). Consequently, we make an initial step to develop the web service IntApop that provides an appropriate platform for apoptosis researchers, systems biologists and translational clinician scientists to predict apoptotic protein interactions in human. In addition, the interaction network can be visualized online, making it a widely applicable systems biology tool for apoptosis and cancer researchers. PMID:24120734

  2. L'intégration des accélérateurs du CERN

    CERN Document Server

    Chemli, S; CERN. Geneva. TS Department

    2008-01-01

    L?intégration du LHC a ouvert des perspectives pour une gestion plus complète des accélérateurs du CERN. La base de données LAYOUT a permis d'assurer la continuité des phases de définition optique du projet, d'intégration 3D et de contrôles de conformité des installations. Les scans et modélisations 3D en couches des installations réalisées constituent un outil déterminant pour la préparation des interventions dans le cadre des procédures de sécurité ALARA. Il est proposé de reproduire cette méthodologie pour les nouveaux projets comme pour les accélérateurs existants. La mise à jour de l'anneau SPS dans LAYOUT semble être la priorité. La base de données SURVEY contient déjà une vue d'ensemble des accélérateurs, chaque composant étant référencé dans le Système de Coordonnées du CERN, selon les définitions théoriques "sources" au 1/100 mm. Base pour l'alignement, elle stocke également les positions réelles des machines. Elle complète ainsi l'information linéaire de LAY...

  3. Conception d'antennes miniatures intégrées pour solutions RF SiP

    OpenAIRE

    Jeangeorges, Mickaël

    2010-01-01

    Ce mémoire présente la conception et l'optimisation d'antennes miniatures intégrées en modules de type System in Package. L'objectif est de répondre à un besoin croissant en modules intégrés complets, comprenant tous les composants nécessaires pour apporter des fonctionnalités sans-fil aux objets communicants. Afin de remplir cet objectif, les antennes doivent satisfaire de nombreux critères, autant au niveau des performances (adaptation, bande passante, efficacité, diagramme de rayonnement) ...

  4. Electronic structure of InTe, SnAs and PbSb: Valence-skip compound or not?

    Science.gov (United States)

    Hase, Izumi; Yasutomi, Kouki; Yanagisawa, Takashi; Odagiri, Kousuke; Nishio, Taichiro

    2016-08-01

    InTe, SnAs and PbSb formally have unusual valence states, In2+, Sn3+ and Pb3+. All of them have B1 crystal structure at some pressure range. They are candidates of the valence-skip compound, which may have negative effective Coulomb interaction Ueff electronic structures by ab-initio calculations, and calculated the number of s-electrons at the cation site. We found that InTe is favorable to emerge valence skip, while PbSb is not favorable for valence skip. SnAs is between these two. These findings well agree with the experimental results.

  5. Modélisation de la dynamique de l'intégration contextuelle du mouvement chez le primate

    OpenAIRE

    Tlapale, Émilien

    2011-01-01

    Dans cette thèse, nous étudions l'intégration du mouvement chez le primate. En se basant sur les connaissances actuelles concernant l'anatomie et les fonctions de deux aires corticales impliquées dans le mouvement, v1 et mt, nous expliquons un certain nombre de réponses perceptuelles et oculo-motrices rapportées dans la littérature. Tout d'abord, nous construisons un modèle récurrent d'intégration du mouvement se basant sur un nombre minimal d'hypothèses concernant les inter- actions cortical...

  6. 化学品数据信息搜索引擎ChemDB Portal%ChemDB Portal,A Search Engine for Chemicals

    Institute of Scientific and Technical Information of China (English)

    李晓霞; 袁小龙; 夏诏杰; 聂峰光; 陶晓芳; 唐武成; 郭力

    2011-01-01

    化学品的性质、用途、安全使用等相关的知识是专业人员、特别是工业界的从业人员最大程度地降低健康和环境风险,合理地合成新化学品以及利用已有化学品的基础,也是公众消除对化学的误解、客观认识化学品在日常生活中功用和使用限度的前提。利用网络化、可公开访问的化学数据库资源获取化学品数据信息日益成为首选的途径,但目前对这些数据库的检索仍然是分散的单库检索,利用通用的文本搜索引擎如Google、百度还不能对这些库进行统一、有效的检索。最近几年来为解决网络化学数据库的统一检索问题出现了两种策略,一种基于information repository,另一种基于化学深层网的数据提取。本文简要介绍基于化学深层网的数据提取实现网络上多来源化学数据库统一检索的方法以及在此基础上建立的化学品数据信息搜索引擎ChemDB Portal(http://www.chemdb-portal.cn)。%The properties,uses and safety knowledge on chemicals are essential for professional healthy and environmental risk assessment when academic and industrial professional synthesize new chemicals and make proper use of existing chemicals,which is also a necessity for public to avoid misunderstanding of chemistry and chemicals in daily life.Internet is becoming the first choice for professional and public to find data on chemicals from web based chemical databases.However,there is still no single entry to access the data in distributed chemical databases on Internet,even with the general text search engine like Google and Baidu.There are two approaches to create search engine specific for chemicals in the past 5 to 6 years,one is based on information repository and another is based on the data extraction for Chemistry Deep Web.This paper briefly introduces the data extraction approach and presents ChemDB Portal(http://www.chemdb-portal.cn),a search engine prototype for

  7. WRF fire simulation coupled with a fuel moisture model and smoke transport by WRF-Chem

    CERN Document Server

    Kochanski, Adam K; Mandel, Jan; Kim, Minjeong

    2012-01-01

    We describe two recent additions to WRF coupled with a fire spread model. Fire propagation is strongly dependent on fuel moisture, which in turn depends on the history of the atmosphere. We have implemented a equilibrium time-lag model of fuel moisture driven by WRF variables. The code allows the user to specify fuel parameters, with the defaults calibrated to the Canadian fire danger rating system for 10-hour fuel. The moisture model can run coupled with the atmosphere-fire model, or offline from WRF output to equilibrate the moisture over a period of time and to provide initial moisture conditions for a coupled atmosphere-fire-moisture simulation. The fire model also inserts smoke tracers into WRF-Chem to model the transport of fire emissions. The coupled model is available from OpenWFM.org. An earlier version of the fire model coupled with atmosphere is a part of WRF release.

  8. Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model.

    Science.gov (United States)

    Wang, Long; Wang, Shuxiao; Zhang, Lei; Wang, Yuxuan; Zhang, Yanxu; Nielsen, Chris; McElroy, Michael B; Hao, Jiming

    2014-07-01

    China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35-50% of THg concentration and 50-70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. PMID:24768744

  9. Design and Analysis of a Preconcentrator for the ChemLab

    Energy Technology Data Exchange (ETDEWEB)

    WONG,CHUNGNIN C.; FLEMMING,JEB H.; MANGINELL,RONALD P.; KOTTENSTETTE,RICHARD; FRYE-MASON,GREGORY CHARLES

    2000-07-17

    Preconcentration is a critical analytical procedure when designing a microsystem for trace chemical detection, because it can purify a sample mixture and boost the small analyte concentration to a much higher level allowing a better analysis. This paper describes the development of a micro-fabricated planar preconcentrator for the {mu}ChemLab{trademark} at Sandia. To guide the design, an analytical model to predict the analyte transport, adsorption and resorption process in the preconcentrator has been developed. Experiments have also been conducted to analyze the adsorption and resorption process and to validate the model. This combined effort of modeling, simulation, and testing has led us to build a reliable, efficient preconcentrator with good performance.

  10. The PubChemQC Project: a large chemical database from the first principle calculations

    CERN Document Server

    Nakata, Maho

    2015-01-01

    In this research, we have been constructing a large database of molecules by {\\it ab initio} calculations. Currently, we have over 1.53 million entries of 6-31G* B3LYP optimized geometries and ten excited states by 6-31+G* TDDFT calculations. To calculate molecules, we only refer the InChI (International Chemical Identifier) representation of chemical formula by the International Union of Pure and Applied Chemistry (IUPAC), thus, no reference to experimental data. These results are open to public at http://pubchemqc.riken.jp/. The molecular data have been taken from the PubChem Project (http://pubchem.ncbi.nlm.nih.gov/) which is one of the largest in the world (approximately 63 million molecules are listed) and free (public domain) database. Our final goal is, using these data, to develop a molecular search engine or molecular expert system to find molecules which have desired properties.

  11. HExpoChem: a systems biology resource to explore human exposure to chemicals

    DEFF Research Database (Denmark)

    Taboureau, Olivier; Jacobsen, Ulrik Plesner; Kalhauge, Christian Gram;

    2013-01-01

    of computational biology approaches are needed to assess the health risks of chemical exposure. Here we present HExpoChem, a tool based on environmental chemicals and their bioactivities on human proteins with the objective of aiding the qualitative exploration of human exposure to chemicals. The......Summary: Humans are exposed to diverse hazardous chemicals daily. Although an exposure to these chemicals is suspected to have adverse effects on human health, mechanistic insights into how they interact with the human body are still limited. Therefore, acquisition of curated data and development...... chemical–protein interactions have been enriched with a quality-scored human protein–protein interaction network, a protein–protein association network and a chemical–chemical interaction network, thus allowing the study of environmental chemicals through formation of protein complexes and phenotypic...

  12. The PubChemQC project: A large chemical database from the first principle calculations

    Science.gov (United States)

    Maho, Nakata

    2015-12-01

    In this research, we have been constructing a large database of molecules by ab initio calculations. Currently, we have over 1.53 million entries of 6-31G* B3LYP optimized geometries and ten excited states by 6-31+G* TDDFT calculations. To calculate molecules, we only refer the InChI (International Chemical Identifier) representation of chemical formula by the International Union of Pure and Applied Chemistry (IUPAC), thus, no reference to experimental data. These results are open to public at http://pubchemqc.riken.jp/. The molecular data have been taken from the PubChem Project (http://pubchem.ncbi.nlm.nih.gov/) which is one of the largest in the world (approximately 63 million molecules are listed) and free (public domain) database. Our final goal is, using these data, to develop a molecular search engine or molecular expert system to find molecules which have desired properties.

  13. A fast stratospheric chemistry solver: the E4CHEM submodel for the atmospheric chemistry global circulation model EMAC

    Directory of Open Access Journals (Sweden)

    A. J. G. Baumgaertner

    2010-02-01

    Full Text Available The atmospheric chemistry general circulation model ECHAM5/MESSy (EMAC and the atmospheric chemistry box model CAABA are extended by a computationally very efficient submodel for atmospheric chemistry, E4CHEM. It focuses on stratospheric chemistry but also includes background tropospheric chemistry. It is based on the chemistry of MAECHAM4-CHEM and is intended to serve as a simple and fast alternative to the flexible but also computationally more demanding submodel MECCA. In a model setup with E4CHEM, EMAC is now also suitable for simulations of longer time scales. The reaction mechanism contains basic O3, CH4, CO, HOx, NOx and ClOx gas phase chemistry. In addition, E4CHEM includes optional fast routines for heterogeneous reactions on sulphate aerosols and polar stratospheric clouds (substituting the existing submodels PSC and HETCHEM, and scavenging (substituting the existing submodel SCAV. We describe the implementation of E4CHEM into the MESSy structure of CAABA and EMAC. For some species the steady state in the box model differs by up to 100% when compared to results from CAABA/MECCA due to different reaction rates. After an update of the reaction rates in E4CHEM the mixing ratios in both boxmodel and 3-D model simulations are in satisfactory agreement with the results from a simulation where MECCA with a similar chemistry scheme was employed. Finally, a comparison against a simulation with a more complex and already evaluated chemical mechanism is presented in order to discuss shortcomings associated with the simplification of the chemical mechanism.

  14. Mixed Waste Treatment Using the ChemChar Thermolytic Detoxification Technique

    International Nuclear Information System (INIS)

    This R and D program addresses the treatment of mixed waste employing the ChemChar Thermolytic Detoxification process. Surrogate mixed waste streams will be treated in a four inch diameter, continuous feed, adiabatic reactor with the goal of meeting all regulatory treatment levels for the contaminants in the surrogates with the concomitant production of contaminant free by-products. Successful completion of this program will show that organic contaminants in mixed waste surrogates will be converted to a clean, energy rich synthesis gas capable of being used, without further processing, for power or heat generation. The inorganic components in the surrogates will be found to be adsorbed on a macroporous coal char activated carbon substrate which is mixed with the waste prior to treatment. These contaminants include radioactive metal surrogate species, RCRA hazardous metals and any acid gases formed during the treatment process. The program has three main tasks that will be performed to meet the above objectives. The first task is the design and construction of the four inch reactor at Mirage Systems in Sunnyvale, CA. The second task is production and procurement of the activated carbon char employed in the ChemChartest runs and identification of two surrogate mixed wastes. The last task is testing and operation of the reactor on char/surrogate waste mixtures to be performed at the University of Missouri. The deliverables for the project are a Design Review Report, Operational Test Plan, Topical Report and Final Report. This report contains only the results of the design and construction carbon production-surrogate waste identification tasks.Treatment of the surrogate mixed wastes has just begun and will not be reported in this version of the Final Report. The latter will be reported in the final version of the Final Report

  15. Mixed Waste Treatment Using the ChemChar Thermolytic Detoxification Technique

    Energy Technology Data Exchange (ETDEWEB)

    Kuchynka, D.J.

    1997-01-01

    This R and D program addresses the treatment of mixed waste employing the ChemChar Thermolytic Detoxification process. Surrogate mixed waste streams will be treated in a four inch diameter, continuous feed, adiabatic reactor with the goal of meeting all regulatory treatment levels for the contaminants in the surrogates with the concomitant production of contaminant free by-products. Successful completion of this program will show that organic contaminants in mixed waste surrogates will be converted to a clean, energy rich synthesis gas capable of being used, without further processing, for power or heat generation. The inorganic components in the surrogates will be found to be adsorbed on a macroporous coal char activated carbon substrate which is mixed with the waste prior to treatment. These contaminants include radioactive metal surrogate species, RCRA hazardous metals and any acid gases formed during the treatment process. The program has three main tasks that will be performed to meet the above objectives. The first task is the design and construction of the four inch reactor at Mirage Systems in Sunnyvale, CA. The second task is production and procurement of the activated carbon char employed in the ChemChartest runs and identification of two surrogate mixed wastes. The last task is testing and operation of the reactor on char/surrogate waste mixtures to be performed at the University of Missouri. The deliverables for the project are a Design Review Report, Operational Test Plan, Topical Report and Final Report. This report contains only the results of the design and construction carbon production-surrogate waste identification tasks.Treatment of the surrogate mixed wastes has just begun and will not be reported in this version of the Final Report. The latter will be reported in the final version of the Final Report.

  16. Viral vectors for gene modification of plants as chem/bio sensors.

    Energy Technology Data Exchange (ETDEWEB)

    Manginell, Monica; Harper, Jason C.; Arango, Dulce C.; Brozik, Susan Marie; Dolan, Patricia L.

    2006-11-01

    Chemical or biological sensors that are specific, sensitive, and robust allowing intelligence gathering for verification of nuclear non-proliferation treaty compliance and detouring production of weapons of mass destruction are sorely needed. Although much progress has been made in the area of biosensors, improvements in sensor lifetime, robustness, and device packaging are required before these devices become widely used. Current chemical and biological detection and identification techniques require less-than-covert sample collection followed by transport to a laboratory for analysis. In addition to being expensive and time consuming, results can often be inconclusive due to compromised sample integrity during collection and transport. We report here a demonstration of a plant based sensor technology which utilizes mature and seedling plants as chemical sensors. One can envision genetically modifying native plants at a site of interest that can report the presence of specific toxins or chemicals. In this one year project we used a developed inducible expression system to show the feasibility of plant sensors. The vector was designed as a safe, non-infectious vector which could be used to invade, replicate, and introduce foreign genes into mature host plants that then allow the plant to sense chem/bio agents. The genes introduced through the vector included a reporter gene that encodes for green fluorescent protein (GFP) and a gene that encodes for a mammalian receptor that recognizes a chemical agent. Specifically, GFP was induced by the presence of 17-{beta}-Estradiol (estrogen). Detection of fluorescence indicated the presence of the target chemical agent. Since the sensor is a plant, costly device packaging development or manufacturing of the sensor were not required. Additionally, the biological recognition and reporting elements are maintained in a living, natural environment and therefore do not suffer from lifetime disadvantages typical of most biosensing

  17. Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans.

    Science.gov (United States)

    Shahin-Jafari, Ariyo; Bayat, Mansour; Shahhosseiny, Mohammad Hassan; Tajik, Parviz; Roudbar-Mohammadi, Shahla

    2016-05-01

    Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were exposed at 4 °C to a fixed magnitude of radiation with different time periods of 10, 70, 210, 350 and 490 h. The other 5 tubes were kept far enough from radiation. The samples underwent genomic DNA extraction. PCR amplification of alpha-Int1 gene sequence was done using one set of primers. PCR products were resolved using agarose gel electrophoresis and the nucleotide sequences were determined. All samples showed a clear electrophoretic band around 441 bp and further sequencing revealed the amplified DNA segments are related to alpha-Int1 gene of the yeast. No mutations in the gene were seen in radiation exposed samples. Long-term exposure of the yeast to mobile phone radiation under the above mentioned conditions had no mutagenic effect on alpha-Int1 gene sequence. PMID:27081370

  18. Los intérpretes generales de Yucatán: hombres entre dos mundos

    Directory of Open Access Journals (Sweden)

    Mark Lentz

    2009-01-01

    Full Text Available Este artículo se centra en un tipo importante de intermediarios en el Yucatán colonial, los intérpretes generales del Juzgado Privado de Indios de Yucatán. Desde la época de Gaspar Antonio Chi en 1580 hasta la desaparición de esta corte en la década de 1820, estos hombres mediaron directamente en disputas de propiedades, quejas contra las autoridades, y tradujeron decretos inicialmente publicados en español para la mayoría maya hablante de la provincia. Sus actividades demuestran que Yucatán poseyó un alto número de individuos que dominaron tanto el maya como el español hasta finales del periodo colonial. Además, la cantidad de individuos calificados sirviendo extra oficial mente como intérpretes durante finales del siglo dieciocho, y el sorprendente número de no-mayas que necesitaron sus servicios, muestran también que el periodo colonial fue una época en la que el maya se extendió como lenguaje predominante en Yucatán, en lugar de una época de declive para ese idioma.This paper focuses one type of important intermediaries of colonial Yucatan, the general interpreters of Yucatan's Juzgado Privado de Indios. From the time of Gaspar Antonio Chi in 1580 until the demise of this court in the 1820s, these men mediated directly in land disputes, complaints against priests and other officials, and translated decrees initially published in Spanish for the province's Maya-speaking majority. The activities of the interpreters demonstrate that Yucatan had a high number of individuals literate and fluent in both Maya and Spanish until the close of the colonial period. Furthermore, the quantity of qualified individuals serving unofficially as interpreters during the late eighteenth century and the surprising number of non-Mayas in need of their services also shows that the colonial period was a time in which Maya spread as the predominant language of Yucatan rather than a time of decline for the region's native language.

  19. Intérprete, tu serás Interpreter, you will be

    Directory of Open Access Journals (Sweden)

    Márcia Atálla Pietroluongo

    2011-12-01

    Full Text Available País bilíngue, fundamental no campo dos Estudos da Tradução por suas pesquisas em Terminologia e em Tradução jurídica, o Canadá promoveu e promove inúmeras iniciativas públicas, através de seu Bureau de Traduction, dentre outros organismos, para responder às diversas necessidades nacionais internas. O presente trabalho apresentará um acórdão da Corte Suprema da Nova-Escócia, província do Canadá, conhecido na jurisprudência canadense como o Acórdão Tran (1994, importante documento que estabeleceu pela primeira vez critérios para a fundamentação da "boa interpretação" no meio judicial. Tal decisão da Corte canadense foi incorporada ao Guia para Intérpretes Judiciários, do Ministério da Justiça do Quebec - Direção Geral dos Serviços de Justiça e dos Registros (janeiro de 2001, com edição revista em 2008, traduzido e adaptado por Pierrette Richard, Intérprete Judiciária no Palácio de Justiça de Montreal, do Freelance Court Interpreter's (1995, produzido pelo Serviço de Interpretação Judiciária do Ministério do Procurador Geral de Ontario.A bilingual country, essential in the Translation Studies field for its research on Terminology and Legal Translation, Canada has promoted in the past, and still does, multiple public initiatives, through its Bureau de Traduction, among other bodies, in order to respond to its various national internal needs. This work will present an appellate decision to the Supreme Court of Nova Scotia, a Canadian province, referred in case law as the Tran Decision (1994, an important document which for the first time has set forth the criteria for the grounds of "good interpretation" in the judicial milieu. Such decision from the Canada Court was included in the Guide for Court Interpreters, issued by the Quebec Ministry of Justice - General Direction of Justice and Registration Services (January 2001, revised in 2008, translated and adapted by Pierrette Richard, Court Interpreter in

  20. Comment on ``The application of the thermodynamic perturbation theory to study the hydrophobic hydration'' [J. Chem. Phys. 139, 024101 (2013)

    Science.gov (United States)

    Graziano, Giuseppe

    2013-09-01

    It is shown that the behaviour of the hydration thermodynamic functions obtained in the 3D Mercedes-Benz model of water by Mohoric et al. [J. Chem. Phys. 139, 024101 (2013)] is not qualitatively correct with respect to experimental data for a solute whose diameter is 1.5-fold larger than that of a water molecule. It is also pointed out that the failure is due to the fact that the used 3D Mercedes-Benz model of water [A. Bizjak, T. Urbic, V. Vlachy, and K. A. Dill, J. Chem. Phys. 131, 194504 (2009)] does not reproduce in a quantitatively correct manner the peculiar temperature dependence of water density.

  1. Photoelectron Spectroscopy Study of [Ta2B6]-: a Hexagonal Bipyramdial Cluster

    Science.gov (United States)

    Jian, Tian; Li, Weili; Romanescu, Constantin; Wang, Lai-Sheng

    2014-06-01

    It has been a long-sought goal in cluster science to discover stable atomic clusters as building blocks for cluster-assembled nanomaterials, as exemplified by the fullerenes and their subsequent bulk syntheses.[1,2] Clusters have also been considered as models to understand bulk properties, providing a bridge between molecular and solid-state chemistry.[3] Herein we report a joint photoelectron spectroscopy and theoretical study on the [Ta2B6]- and [Ta2B6] clusters.[4] The photoelectron spectrum of [Ta2B6]- displays a simple spectral pattern and a large HOMO-LUMO gap, suggesting its high symmetry. Theoretical calculations show that both the neutral and anion are D6h pyramidal. The chemical bonding analyses for [Ta2B6] revealed the nature of the B6 and Ta interactions and uncovered strong covalent bonding between B6 and Ta. The D6h-[TaB6Ta] gaseous cluster is reminiscent of the structural pattern in the ReB6X6Re core in the [(Cp*Re)2B6H4Cl2] and the TiB6Ti motif in the newly synthesized Ti7Rh4Ir2B8 solid-state compound.[5,6] The current work provides an intrinsic link between a gaseous cluster and motifs for solid materials. Continued investigations of the transition-metal boron clusters may lead to the discovery of new structural motifs involving pure boron clusters for the design of novel boride materials. Reference [1] H.W. Kroto, J. R. Heath, S. C. OBrien, R. F. Curl, R. E. Smalley, Nature 1985, 318, 162 - 163. [2] W. Krtschmer, L. D. Lamb, K. Fostiropoulos, D. R. Huffman, Nature 1990, 347, 354 - 358. [3] T. P. Fehlner, J.-F. Halet, J.-Y. Saillard, Molecular Clusters: A Bridge to Solid-State Chemitry, Cambridge University Press, UK, 2007. [4] W. L. Li, L. Xie, T. Jian, C. Romanescu, X. Huang, L.-S. Wang, Angew. Chem. Int. Ed. 2014, 126, 1312 - 1316. [5] B. Le Guennic, H. Jiao, S. Kahlal, J.-Y. Saillard, J.-F. Halet, S. Ghosh, M. Shang, A. M. Beatty, A. L. Rheingold, T. P. Fehlner, J. Am. Chem. Soc. 2004, 126, 3203 - 3217. [6] B. P. T. Fokwa, M. Hermus, Angew

  2. Upgrading from the Dicon Wiring Management system to IntEC at the Gentilly 2 station

    International Nuclear Information System (INIS)

    The General Electric DICON Wiring Management system supplied to HQ during the construction of G2 is currently being replaced by the stand-alone version of the IntEC software developed by AECL. The reasons for replacing DICON and choosing lntEC are discussed. The different aspects of the two year DICON data conversion project are presented with the problems encountered and the means that were taken to resolve the problems. lntEC has shown our DICON data to be considerably more deficient than we had thought. This has increased the cost and the duration of the conversion process. However, correcting the errors during the conversion process provides us with much more accurate data. This should be viewed as an investment in configuration management. Many potential causes of future errors and potentially critical path delays have been removed. We have chosen to document the detailed procedures for the use of lntEC in our plant using a Windows Help File compiler. This also has been found to be extremely useful as a training tool as well as providing on-line help. The DICON data conversion into lntEC will not be completed until 1996. lntEC is not perfect. However, from what we have up to now, we are satisfied with the conviviality and efficiency of lntEC and with AECL's diligence in constantly aspiring in making it a better product. (author)

  3. Sujet de droit et sujet d’intérêt : Montesquieu lu par Foucault

    Directory of Open Access Journals (Sweden)

    Céline Spector

    2007-04-01

    Full Text Available Dans les cours au Collège de France réunis dans Naissance de la biopolitique, Foucault soutient qu’une science économico-juridique est rigoureusement impossible. Or cette thèse radicale mérite discussion, à partir d’un auteur trop souvent ignoré des historiens de la genèse de l’économie politique. Montesquieu, à sa façon, contribue à la constitution de ce savoir économico-juridique, susceptible de penser ensemble sujet d’intérêt et sujet de droit. L’esprit de cette étude ne sera pas de critiquer Foucault en montrant que Montesquieu ne « rentre » pas dans l’opposition de ses paradigmes, mais plutôt de tenter de mesurer l’originalité d’une pensée qui conçoit des échanges entre propriété et liberté qui ont pour effet d’unifier rationalité économique et rationalité juridique.

  4. Gas-phase chemistry of actinides ions: new insights into the reaction of UO+ and UO+2 with H2O

    International Nuclear Information System (INIS)

    Complete text of publication follows: Reaction pathways for the interaction of uranium monoxide cations with water were studied by using different approaches of Density Functional Theory. Firstly, relativistic small-core pseudopotentials were used together with B3LYP hybrid functional. In addition, frozen-core PW91-PW91 calculations were performed within the ZORA approximation. A close description of the reaction mechanisms leading to different dissociation channels is presented, including all the involved minima and transition states [1]. Different possible spin states were considered as well as the effect of spin-orbit interactions (SO-ZORA) on the transition state barrier heights. The obtained results are compared with recent experimental data [2] as well as with previous theoretical studies of the reaction of bare uranium cations with water [3], in order to analyse the influence of the oxo-ligand in reactivity. References: [1] Michelini, M.C.; Russo, N.; Sicilia, E.J. Am. Chem. Soc., to be published; [2] (a) Jackson, G. P.; King, F. L.; Goeringer, D. E.; Duckworth, D. C. J. Phys. Chem. A 2002, 106, 7788; (b) Cornehl, H.H.; Wesendrup, R.; Diefenbach, M.; Schwarz, H. Chem. Eur. J. 1997, 3, 1083; (c) Gibson, J. K.; Haire, R. G.; Santos, M.; Marcalo, J.; Pires de Matos, A. J. Phys. Chem. A 2005, 109, 2768; [3] Michelini, M.C.; Russo, N.; Sicilia, E. Angew. Chem. Int. Ed., 2006, 45, 1095

  5. Gas-phase chemistry of actinides ions: new insights into the reaction of UO{sup +} and UO{sup +2} with H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Michelini, M.D.C.; Russo, N.; Sicilia, E. [Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d Eccellenza MURST, Universita della Calabria, I-87030 Arcavacata di Rende, (Italy)

    2007-07-01

    Complete text of publication follows: Reaction pathways for the interaction of uranium monoxide cations with water were studied by using different approaches of Density Functional Theory. Firstly, relativistic small-core pseudopotentials were used together with B3LYP hybrid functional. In addition, frozen-core PW91-PW91 calculations were performed within the ZORA approximation. A close description of the reaction mechanisms leading to different dissociation channels is presented, including all the involved minima and transition states [1]. Different possible spin states were considered as well as the effect of spin-orbit interactions (SO-ZORA) on the transition state barrier heights. The obtained results are compared with recent experimental data [2] as well as with previous theoretical studies of the reaction of bare uranium cations with water [3], in order to analyse the influence of the oxo-ligand in reactivity. References: [1] Michelini, M.C.; Russo, N.; Sicilia, E.J. Am. Chem. Soc., to be published; [2] (a) Jackson, G. P.; King, F. L.; Goeringer, D. E.; Duckworth, D. C. J. Phys. Chem. A 2002, 106, 7788; (b) Cornehl, H.H.; Wesendrup, R.; Diefenbach, M.; Schwarz, H. Chem. Eur. J. 1997, 3, 1083; (c) Gibson, J. K.; Haire, R. G.; Santos, M.; Marcalo, J.; Pires de Matos, A. J. Phys. Chem. A 2005, 109, 2768; [3] Michelini, M.C.; Russo, N.; Sicilia, E. Angew. Chem. Int. Ed., 2006, 45, 1095.

  6. Rotational Analysis of FTIR Spectra from Cigarette Smoke: An Application of Chem Spec II Software in the Undergraduate Laboratory

    Science.gov (United States)

    Ford, Alan R.; Burns, William A.; Reeve, Scott W.

    2004-01-01

    A version of the classic gas phase infrared experiment was developed for students at Arkansas State University based on the shortcomings of the rotationally resolved infrared experiment. Chem Spec II is a noncommercial Windows-based software package developed to aid in the potentially complicated problem of assigning quantum numbers to observed…

  7. Chemistry Outreach Project to High Schools Using a Mobile Chemistry Laboratory, ChemKits, and Teacher Workshops

    Science.gov (United States)

    Long, Gary L.; Bailey, Carol A.; Bunn, Barbara B.; Slebodnick, Carla; Johnson, Michael R.; Derozier, Shad

    2012-01-01

    The Chemistry Outreach Program (ChOP) of Virginia Tech was a university-based outreach program that addressed the needs of high school chemistry classes in underfunded rural and inner-city school districts. The primary features of ChOP were a mobile chemistry laboratory (MCL), a shipping-based outreach program (ChemKits), and teacher workshops.…

  8. Evaluating the Effectiveness of the Open-Access ChemWiki Resource as a Replacement for Traditional General Chemistry Textbooks

    Science.gov (United States)

    Allen, Gregory; Guzman-Alvarez, Alberto; Smith, Amy; Gamage, Alan; Molinaro, Marco; Larsen, Delmar S.

    2015-01-01

    Open educational resources (OERs) provide a potential alternative to costly textbooks and can allow content to be edited and adapted to a variety of classroom environments. At the University of California, Davis, the OER "ChemWiki" project, as part of the greater STEMWiki Hyperlibrary, was developed to supplant traditional post-secondary…

  9. The "Virtual ChemLab" Project: A Realistic and Sophisticated Simulation of Organic Synthesis and Organic Qualitative Analysis

    Science.gov (United States)

    Woodfield, Brian F.; Andrus, Merritt B.; Waddoups, Gregory L.; Moore, Melissa S.; Swan, Richard; Allen, Rob; Bodily, Greg; Andersen, Tricia; Miller, Jordan; Simmons, Bryon; Stanger, Richard

    2005-01-01

    A set of sophisticated and realistic laboratory simulations is created for use in freshman- and sophomore-level chemistry classes and laboratories called 'Virtual ChemLab'. A detailed assessment of student responses is provided and the simulation's pedagogical utility is described using the organic simulation.

  10. ChemVoyage: A Web-Based, Simulated Learning Environment with Scaffolding and Linking Visualization to Conceptualization

    Science.gov (United States)

    McRae, Christopher; Karuso, Peter; Liu, Fei

    2012-01-01

    The Web is now a standard tool for information access and dissemination in higher education. The prospect of Web-based, simulated learning platforms and technologies, however, remains underexplored. We have developed a Web-based tutorial program (ChemVoyage) for a third-year organic chemistry class on the topic of pericyclic reactions to…

  11. Interpreting aerosol lifetimes using the GEOS-Chem model and constraints from radionuclide measurements

    Science.gov (United States)

    Croft, B.; Pierce, J. R.; Martin, R. V.

    2014-04-01

    Aerosol removal processes control global aerosol abundance, but the rate of that removal remains uncertain. A recent study of aerosol-bound radionuclide measurements after the Fukushima Daiichi nuclear power plant accident documents 137Cs removal (e-folding) times of 10.0-13.9 days, suggesting that mean aerosol lifetimes in the range of 3-7 days in global models might be too short by a factor of two. In this study, we attribute this discrepancy to differences between the e-folding and mean aerosol lifetimes. We implement a simulation of 137Cs and 133Xe into the GEOS-Chem chemical transport model and examine the removal rates for the Fukushima case. We find a general consistency between modelled and measured e-folding times. The simulated 137Cs global burden e-folding time is about 14 days. However, the simulated mean lifetime of aerosol-bound 137Cs over a 6-month post-accident period is only 1.8 days. We find that the mean lifetime depends strongly on the removal rates in the first few days after emissions, before the aerosols leave the boundary layer and are transported to altitudes and latitudes where lifetimes with respect to wet removal are longer by a few orders of magnitude. We present sensitivity simulations that demonstrate the influence of differences in altitude and location of the radionuclides on the mean lifetime. Global mean lifetimes are shown to strongly depend on the altitude of injection. The global mean 137Cs lifetime is more than one order of magnitude greater for the injection at 7 km than into the boundary layer above the Fukushima site. Instantaneous removal rates are slower during the first few days after the emissions for a free tropospheric versus boundary layer injection and this strongly controls the mean lifetimes. Global mean aerosol lifetimes for the GEOS-Chem model are 3-6 days, which is longer than that for the 137Cs injected at the Fukushima site (likely due to precipitation shortly after Fukushima emissions), but similar to the

  12. ChemCam results from the Shaler outcrop in Gale crater, Mars

    Science.gov (United States)

    Anderson, Ryan; Bridges, J. C.; Williams, A.; Edgar, L.; Ollila, A.; Williams, J.; Nachon, M.; Mangold, N.; Fisk, M.; Schieber, J.; Gupta, S.; Dromart, G.; Wiens, R.; Le Mouélic, S.; Forni, O.; Lanza, N.; Mezzacappa, A.; Sautter, V.; Blaney, D.; Clark, B.; Clegg, S.; Gasnault, O.; Lasue, J.; Léveillé, R.; Lewin, E.; Lewis, K. W.; Maurice, S.; Newsom, H.; Schwenzer, S. P.; Vaniman, D.

    2015-03-01

    The ChemCam campaign at the fluvial sedimentary outcrop "Shaler" resulted in observations of 28 non-soil targets, 26 of which included active laser induced breakdown spectroscopy (LIBS), and all of which included Remote Micro-Imager (RMI) images. The Shaler outcrop can be divided into seven facies based on grain size, texture, color, resistance to erosion, and sedimentary structures. The ChemCam observations cover Facies 3 through 7. For all targets, the majority of the grains were below the limit of the RMI resolution, but many targets had a portion of resolvable grains coarser than ∼0.5 mm. The Shaler facies show significant scatter in LIBS spectra and compositions from point to point, but several key compositional trends are apparent, most notably in the average K2O content of the observed facies. Facies 3 is lower in K2O than the other facies and is similar in composition to the "snake," a clastic dike that occurs lower in the Yellowknife Bay stratigraphic section. Facies 7 is enriched in K2O relative to the other facies and shows some compositional and textural similarities to float rocks near Yellowknife Bay. The remaining facies (4, 5, and 6) are similar in composition to the Sheepbed and Gillespie Lake members, although the Shaler facies have slightly elevated K2O and FeOT. Several analysis points within Shaler suggest the presence of feldspars, though these points have excess FeOT which suggests the presence of Fe oxide cement or inclusions. The majority of LIBS analyses have compositions which indicate that they are mixtures of pyroxene and feldspar. The Shaler feldspathic compositions are more alkaline than typical feldspars from shergottites, suggesting an alkaline basaltic source region, particularly for the K2O-enriched Facies 7. Apart from possible iron-oxide cement, there is little evidence for chemical alteration at Shaler, although calcium-sulfate veins comparable to those observed lower in the stratigraphic section are present. The differing

  13. Numerical simulation for regional ozone concentrations: A case study by weather research and forecasting/chemistry (WRF/Chem) model

    Energy Technology Data Exchange (ETDEWEB)

    Habib Al Razi, Khandakar Md; Hiroshi, Moritomi [Environmental and Renewable Energy System, Graduate School of Engineering, Gifu University, 1-1 Yanagido, Gifu City, 501-1193 (Japan)

    2013-07-01

    The objective of this research is to better understand and predict the atmospheric concentration distribution of ozone and its precursor (in particular, within the Planetary Boundary Layer (Within 110 km to 12 km) over Kasaki City and the Greater Tokyo Area using fully coupled online WRF/Chem (Weather Research and Forecasting/Chemistry) model. In this research, a serious and continuous high ozone episode in the Greater Tokyo Area (GTA) during the summer of 14–18 August 2010 was investigated using the observation data. We analyzed the ozone and other trace gas concentrations, as well as the corresponding weather conditions in this high ozone episode by WRF/Chem model. The simulation results revealed that the analyzed episode was mainly caused by the impact of accumulation of pollution rich in ozone over the Greater Tokyo Area. WRF/Chem has shown relatively good performance in modeling of this continuous high ozone episode, the simulated and the observed concentrations of ozone, NOx and NO2 are basically in agreement at Kawasaki City, with best correlation coefficients of 0.87, 0.70 and 0.72 respectively. Moreover, the simulations of WRF/Chem with WRF preprocessing software (WPS) show a better agreement with meteorological observations such as surface winds and temperature profiles in the ground level of this area. As a result the surface ozone simulation performances have been enhanced in terms of the peak ozone and spatial patterns, whereas WRF/Chem has been succeeded to generate meteorological fields as well as ozone, NOx, NO2 and NO.

  14. Development by Genetic Immunization of Monovalent Antibodies (Nanobodies) Behaving as Antagonists of the Human ChemR23 Receptor.

    Science.gov (United States)

    Peyrassol, Xavier; Laeremans, Toon; Gouwy, Mieke; Lahura, Vannessa; Debulpaep, Maja; Van Damme, Jo; Steyaert, Jan; Parmentier, Marc; Langer, Ingrid

    2016-03-15

    The generation of Abs that recognize the native conformation of G protein-coupled receptors can be a challenging task because, like most multimembrane-spanning proteins, they are extremely difficult to purify as native protein. By combining genetic immunization, phage display, and biopanning, we identified two functional monovalent Abs (nanobodies) targeting ChemR23. The two nanobodies (CA4910 and CA5183) were highly specific for the human receptor and bind ChemR23 with moderate affinity. Binding studies also showed that they share a common binding site that overlaps with that of chemerin, the natural ligand of ChemR23. Consistent with these results, we found that the nanobodies were able to antagonize chemerin-induced intracellular calcium increase. The inhibition was partial when chemerin was used as agonist and complete when the chemerin(149-157) nonapeptide was used as agonist. Engineering of a bivalent CA4910 nanobody resulted in a relatively modest increase in affinity but a marked enhancement of efficacy as an antagonist of chemerin induced intracellular calcium mobilization and a much higher potency against the chemerin(149-157) nonapeptide-induced response. We also demonstrated that the fluorescently labeled nanobodies detect ChemR23 on the surface of human primary cell populations as efficiently as a reference mouse mAb and that the bivalent CA4910 nanobody behaves as an efficient antagonist of chemerin-induced chemotaxis of human primary cells. Thus, these nanobodies constitute new tools to study the role of the chemerin/ChemR23 system in physiological and pathological conditions. PMID:26864035

  15. The ChemCam Instrument Suite on the Mars Science Laboratory (MSL) Rover: Body Unit and Combined System Tests

    International Nuclear Information System (INIS)

    The ChemCam instrument suite on the Mars Science Laboratory (MSL) rover Curiosity provides remote compositional information using the first laser-induced breakdown spectrometer (LIBS) on a planetary mission, and provides sample texture and morphology data using a remote micro-imager (RMI). Overall, ChemCam supports MSL with five capabilities: remote classification of rock and soil characteristics; quantitative elemental compositions including light elements like hydrogen and some elements to which LIBS is uniquely sensitive (e.g., Li, Be, Rb, Sr, Ba); remote removal of surface dust and depth profiling through surface coatings; context imaging; and passive spectroscopy over the 240-905 nm range. ChemCam is built in two sections: The mast unit, consisting of a laser, telescope, RMI, and associated electronics, resides on the rover's mast, and is described in a companion paper. ChemCam's body unit, which is mounted in the body of the rover, comprises an optical de-multiplexer, three spectrometers, detectors, their coolers, and associated electronics and data handling logic. Additional instrument components include a 6 m optical fiber which transfers the LIBS light from the telescope to the body unit, and a set of onboard calibration targets. ChemCam was integrated and tested at Los Alamos National Laboratory where it also underwent LIBS calibration with 69 geological standards prior to integration with the rover. Post-integration testing used coordinated mast and instrument commands, including LIBS line scans on rock targets during system-level thermal-vacuum tests. In this paper we describe the body unit, optical fiber, and calibration targets, and the assembly, testing, and verification of the instrument prior to launch. (authors)

  16. Preliminary performance assessment of biotoxin detection for UWS applications using a MicroChemLab device.

    Energy Technology Data Exchange (ETDEWEB)

    VanderNoot, Victoria A.; Haroldsen, Brent L.; Renzi, Ronald F.; Shokair, Isaac R.

    2010-03-01

    In a multiyear research agreement with Tenix Investments Pty. Ltd., Sandia has been developing field deployable technologies for detection of biotoxins in water supply systems. The unattended water sensor or UWS employs microfluidic chip based gel electrophoresis for monitoring biological analytes in a small integrated sensor platform. This instrument collects, prepares, and analyzes water samples in an automated manner. Sample analysis is done using the {mu}ChemLab{trademark} analysis module. This report uses analysis results of two datasets collected using the UWS to estimate performance of the device. The first dataset is made up of samples containing ricin at varying concentrations and is used for assessing instrument response and detection probability. The second dataset is comprised of analyses of water samples collected at a water utility which are used to assess the false positive probability. The analyses of the two sets are used to estimate the Receiver Operating Characteristic or ROC curves for the device at one set of operational and detection algorithm parameters. For these parameters and based on a statistical estimate, the ricin probability of detection is about 0.9 at a concentration of 5 nM for a false positive probability of 1 x 10{sup -6}.

  17. Plant Chemistry Response to On-Line NobleChemTM

    International Nuclear Information System (INIS)

    Noble metal chemical addition is widely and successfully used in boiling water reactors (BWRs) as a mitigation method for intergranular stress corrosion cracking (IGSCC). This technology is used to reduce the electrochemical corrosion potential (ECP) of reactor internals and associated piping while maintaining low hydrogen injection rates. Over the past six years, BWRs have started to transition away from applying noble metals during refueling outages to the application of noble metals while the reactor is operating at full power using the On-Line NobleChemTM (OLNC) process. The ability to apply noble metals on-line allows for greater reapplication flexibility and eliminates the impact of an application on the duration of refueling outages. As more plants have begun to perform OLNC applications, the industry has started to accumulate a significant amount of reactor water chemistry and operating experience for periods both during and after injections. The intent of this paper is to summarize changes in chemistry parameters typically observed during and after an OLNC application, such as increases in reactor water conductivity and activated corrosion by product levels. These parameters can therefore be used during an OLNC injection as secondary indicators of application progress. This paper will also discuss methods of monitor an application, including direct ECP measurements and the use of secondary indicators. (authors)

  18. AMPTE/CCE CHEM observations of the energetic ion population at geosynchronous altitudes

    Science.gov (United States)

    Daglis, Ioannis A.; Sarris, Emmanuel T.; Wilken, Berend

    1993-01-01

    The paper presents results of a statistical study of average characteristics of the energetic ion population at geosynchronous altitudes, using energetic-ion (1-300 keV/e) measurements from the CHEM spectrometer aboard the AMPTE Charge Composition Explorer between January 1985 and June 1987. Data were sorted into four MLT groups and two extreme geomagnetic activity levels ('very quiet' for AE less than 30 nT and 'very active' for AE greater than 700 nT). A clear quiet-time dayside feature found in the measurements was a dip in H(+) and He(2+) spectra, at 6.6 keV/e in the prenoon sector and at 3.5 keV/e in the postnoon sector. During active times, the ion fluxes increased (except for He(+)), and the O(+) contribution to the total energy density increased dramatically. The pitch angle distributions were normal during quiet times and isotropic or field-aligned during active times.

  19. An influence of polyHEMA gate layer on properties of ChemFETs

    Directory of Open Access Journals (Sweden)

    Wladyslaw Torbicz

    2003-06-01

    Full Text Available A complex deposition procedure of the hydrogel layer of modified poly(2-hydroxyethyl methacrylate (polyHEMA covalently linked to the silicon nitride surface and covering only the gate area of the ISFET, was optimized for photolithographic technology, using standard silicon wafers of 3” diameter. The influence of hydrogel composition and layer thickness on the sensors’ parameters was investigated. It was shown, that ISFETs covered with more than 100 μm thick polyHEMA layers in restricted pH-range could be practically insensitive to pH. Regarding mechanical stability of ion-selective sensors, a polyHEMA layer of ca. 20 μm thickness was found to be the best suitable for further manufacturing of durable ion selective sensors (Chemically modified Field-Effect Transistors – ChemFETs. The weak buffering properties of the thin polyHEMA layers had no disadvantageous influence on the sensors’ function.

  20. The Virtual ChemLab Project: A Realistic and Sophisticated Simulation of Inorganic Qualitative Analysis

    Science.gov (United States)

    Woodfield, Brian F.; Catlin, Heidi R.; Waddoups, Gregory L.; Moore, Melissa S.; Swan, Richard; Allen, Rob; Bodily, Greg

    2004-11-01

    We have created a set of sophisticated and realistic laboratory simulations for use in freshman- and sophomore-level chemistry classes and laboratories called Virtual ChemLab. We have completed simulations for Inorganic Qualitative Analysis, Organic Synthesis and Organic Qualitative Analysis, Experiments in Quantum Chemistry, Gas Properties, Titration Experiments, and Calorimetric and Thermochemical Experiments. The purpose of our simulations is to reinforce concepts taught in the classroom, provide an environment for creative learning, and emphasize the thinking behind instructional laboratory experiments. We have used the inorganic simulation extensively with thousands of students in our department at Brigham Young University. We have learned from our evaluation that: (i) students enjoy using these simulations and find them to be an asset in learning effective problem-solving strategies, (ii) students like the fact that they can both reproduce experimental procedures and explore various topics in ways they choose, and (iii) students naturally divide themselves into two groups: creative learners, who excel in an open-ended environment of virtual laboratories, and structured learners, who struggle in this same environment. In this article, we describe the Inorganic Qualitative Analysis simulation; we also share specific evaluation findings from using the inorganic simulation in classroom and laboratory settings.

  1. Modeling Transport in Gas Chromatography Columns for the Micro-ChemLab

    International Nuclear Information System (INIS)

    The gas chromatography (GC) column is a critical component in the microsystem for chemical detection ((mu)ChemLab(trademark)) being developed at Sandia. The goal is to etch a meter-long GC column onto a 1-cm(sup 2) silicon chip while maintaining good chromatographic performance. Our design strategy is to use a modeling and simulation approach. We have developed an analytical tool that models the transport and surface interaction process to achieve an optimized design of the GC column. This analytical tool has a flow module and a separation module. The flow module considers both the compressibility and slip flow effects that may significantly influence the gas transport in a long and narrow column. The separation module models analyte transport and physico-chemical interaction with the coated surface in the GC column. It predicts the column efficiency and performance. Results of our analysis will be presented in this paper. In addition to the analytical tool, we have also developed a time-dependent adsorption/desorption model and incorporated this model into a computational fluid dynamics (CFD) code to simulate analyte transport and separation process in GC columns. CFD simulations can capture the complex three-dimensional flow and transport dynamics, whereas the analytical tool cannot. Different column geometries have been studied, and results will be presented in this paper. Overall we have demonstrated that the modeling and simulation approach can guide the design of the GC column and will reduce the number of iterations in the device development

  2. Iodine's impact on tropospheric oxidants: a global model study in GEOS-Chem

    Science.gov (United States)

    Sherwen, T.; Evans, M. J.; Carpenter, L. J.; Andrews, S. J.; Lidster, R. T.; Dix, B.; Koenig, T. K.; Sinreich, R.; Ortega, I.; Volkamer, R.; Saiz-Lopez, A.; Prados-Roman, C.; Mahajan, A. S.; Ordóñez, C.

    2016-02-01

    We present a global simulation of tropospheric iodine chemistry within the GEOS-Chem chemical transport model. This includes organic and inorganic iodine sources, standard gas-phase iodine chemistry, and simplified higher iodine oxide (I2OX, X = 2, 3, 4) chemistry, photolysis, deposition, and parametrized heterogeneous reactions. In comparisons with recent iodine oxide (IO) observations, the simulation shows an average bias of ˜ +90 % with available surface observations in the marine boundary layer (outside of polar regions), and of ˜ +73 % within the free troposphere (350 hPa yield a total bromine- and iodine-driven tropospheric O3 burden decrease of 14.4 % compared to a simulation without iodine and bromine chemistry in the model, and a small increase in OH (1.8 %). This is a significant impact and so halogen chemistry needs to be considered in both climate and air quality models. 1 Here OX is defined as O3 + NO2 + 2NO3 + PAN + PMN+PPN + HNO4 + 3N2O5 + HNO3 + BrO + HOBr + BrNO2+2BrNO3 + MPN + IO + HOI + INO2 + 2INO3 + 2OIO+2I2O2 + 3I2O3 + 4I2O4, where PAN = peroxyacetyl nitrate, PPN = peroxypropionyl nitrate, MPN = methyl peroxy nitrate, and MPN = peroxymethacryloyl nitrate.

  3. Att vara eller att inte vara med i en idrottsföreing : - Faktorer som påverkar beslutet

    OpenAIRE

    Clausson, Amalia; Jansson, Patrik

    2012-01-01

    Syftet med denna studie var att ta reda på om ungdomar som valt ett liv inom föreningsidrotten på grund av inre eller yttre motivation och faktorer. Finns det skillnader mellan könen?   Vi kom fram till att det väldigt ofta var den inre motivationen som låg bakom påbörjandet eller upprätthållandet av medlemskapet i en idrottsförening. Av de personer som svarat att de valt att inte vara aktiva utövare i en idrottsförening visar det sig att drygt hälften inte är det på grund av yttre faktorer o...

  4. Environnements logiciels pour une intégration quotidienne de l'EAO dans l'enseignement

    OpenAIRE

    Guéraud, Viviane; Peyrin, Jean-Pierre; David, Jean-Pierre; Pernin, Jean-Philippe

    1993-01-01

    Dans un premier temps, nous présentons le laboratoire Arcade, comme un exemple de produit hypermédia pour l'enseignement de l'algorithmique. Ce faisant, nous défendons un certain style d'EAO, offrant des ressources complémentaires intégrées dans les pratiques pédagogiques quotidiennes des enseignants. Pour permettre une telle intégration, il paraît nécessaire de donner aux enseignants les moyens d'adapter ces ressources à leurs cours, de les enrichir, et même d'en créer de nouvelles. Dans cet...

  5. Mise au point de la protection intégrée du colza : exemple du phoma (Leptosphaeria maculans

    Directory of Open Access Journals (Sweden)

    Aubertot Jean-Noël

    2003-05-01

    Full Text Available En France, le phoma est considéré comme la maladie la plus préoccupante du colza. Il n’existe aucune méthode de lutte à la fois efficace, rentable et respectueuse de l’environnement. Il apparaît donc nécessaire de développer la lutte intégrée de la culture contre cette maladie. Cette communication présente les résultats d’un programme de recherche visant à analyser et à modéliser les effets des systèmes de culture sur le développement de la maladie. Des pistes concrètes pour la mise en oeuvre de la lutte intégrée contre le phoma sont proposées.

  6. Effect of long-term exposure to mobile phone radiation on alpha-Int1 gene sequence of Candida albicans

    OpenAIRE

    Shahin-jafari, Ariyo; Bayat, Mansour; Shahhosseiny, Mohammad Hassan; Tajik, Parviz; Roudbar-mohammadi, Shahla

    2015-01-01

    Over the last decade, communication industries have witnessed a tremendous expansion, while, the biological effects of electromagnetic waves have not been fully elucidated. Current study aimed at evaluating the mutagenic effect of long-term exposure to 900-MHz radiation on alpha-Int1 gene sequences of Candida albicans. A standard 900 MHz radiation generator was used for radiation. 10 ml volumes from a stock suspension of C. albicans were transferred into 10 polystyrene tubes. Five tubes were ...

  7. La perception du migrant et de l’intégration dans l’opinion française

    OpenAIRE

    Brouard, Sylvain; Tiberj, Vincent

    2006-01-01

    Que ce soit autour de l’islamophobie et de son éventuelle montée dans l’opinion, de la nature même de la République française et de son projet ou de l’association entre immigration et délinquance, notre modèle d’intégration pose question. Analyse à partir de deux enquêtes simultanées.

  8. Intimidation homophobe, stratégies d’adaptation et intégration de l’orientation sexuelle

    Directory of Open Access Journals (Sweden)

    Marie-France Goyer

    2015-12-01

    Full Text Available Résumé Cette étude examine l’impact de l’intimidation homophobe et des stratégies d’adaptation sur 6 dimensions de l’intégration de l’orientation sexuelle (OS à partir d’un échantillon de 262 jeunes LGBT. Un modèle de régression linéaire a été réalisé pour chaque dimension, avec la victimisation homophobe et les stratégies d’adaptation comme principales variables indépendantes d’intérêt. La victimisation homophobe était associée à une plus faible affirmation de l’OS et à davantage d’homophobie/biphobie intériorisée, de préoccupations relatives au jugement d’autrui, de confusion identitaire, de dissimulation et de difficultés d’acceptation de l’OS. Les stratégies d’adaptation centrées sur la résolution de problèmes étaient associées à davantage de préoccupations relatives au jugement d’autrui alors que celles centrées sur l’évitement étaient associées à davantage de préoccupations relatives au jugement d’autrui et de difficulté d’acceptation de l’OS. Les résultats appuient l’importance de poursuivre la lutte à l’homophobie/biphobie et de mieux outiller les jeunes pour soutenir l’intégration positive de leur OS.

  9. FXR agonist INT-747 upregulates DDAH expression and enhances insulin sensitivity in high-salt fed Dahl rats.

    Directory of Open Access Journals (Sweden)

    Yohannes T Ghebremariam

    Full Text Available AIMS: Genetic and pharmacological studies have shown that impairment of the nitric oxide (NO synthase (NOS pathway is associated with hypertension and insulin-resistance (IR. In addition, inhibition of NOS by the endogenous inhibitor, asymmetric dimethylarginine (ADMA, may also result in hypertension and IR. On the other hand, overexpression of dimethylarginine dimethylaminohydrolase (DDAH, an enzyme that metabolizes ADMA, in mice is associated with lower ADMA, increased NO and enhanced insulin sensitivity. Since DDAH carries a farnesoid X receptor (FXR-responsive element, we aimed to upregulate its expression by an FXR-agonist, INT-747, and evaluate its effect on blood pressure and insulin sensitivity. METHODS AND RESULTS: In this study, we evaluated the in vivo effect of INT-747 on tissue DDAH expression and insulin sensitivity in the Dahl rat model of salt-sensitive hypertension and IR (Dahl-SS. Our data indicates that high salt (HS diet significantly increased systemic blood pressure. In addition, HS diet downregulated tissue DDAH expression while INT-747 protected the loss in DDAH expression and enhanced insulin sensitivity compared to vehicle controls. CONCLUSION: Our study may provide the basis for a new therapeutic approach for IR by modulating DDAH expression and/or activity using small molecules.

  10. Effects of adding different surfactants on antibiotic resistance genes and intI1 during chicken manure composting.

    Science.gov (United States)

    Zhang, Yajun; Li, Haichao; Gu, Jie; Qian, Xun; Yin, Yanan; Li, Yang; Zhang, Ranran; Wang, Xiaojuan

    2016-11-01

    Aerobic composting is usually employed to treat livestock manure. In this study, a bio-surfactant (rhamnolipid, RL) and chemical surfactant (Tween 80, Tw) were added to chicken manure during composting and their effects were determined on the variations in ARGs and intI1. After composting, the reductions in the RAs of ARGs and intI1 with the addition of Tw (1-4.7logs) were generally greater than that with the addition of RL (0.8-3.7logs) and the control (CK) (0.3-2.6logs), and the enrichment of ARGs was higher with CK (0.9-1.8logs). The ARG profiles were affected significantly by temperature and the water-soluble carbon contents. RL and Tw effectively reduced the concentrations of bio-available Cu and Zn, thereby hindering the co-selection of ARGs by heavy metals. The effects of RL and Tw on ARGs and intI1 indicate that the addition of Tw was slightly more effective than RL after composting. PMID:27526207

  11. Evolution of pentacene films on Ag(1 1 1): Growth beyond the first monolayer

    Science.gov (United States)

    Käfer, Daniel; Witte, Gregor

    2007-07-01

    The formation and structure of pentacene films upon molecular beam deposition at room temperature onto a Ag(1 1 1) surface have been studied by means of SEM, XRD, TDS and NEXAFS. It is shown that multilayer films actually consist of separate crystalline islands revealing a bulk structure reported before by Siegrist et al. [T. Siegrist, C. Kloc, J.H. Schon, B. Batlogg, R.C. Haddon, S. Berg, G.A. Thomas, Angew. Chem. Int. Ed. 40 (2001) 1732]. Distinctly different π ∗-resonances were observed in the C1s NEXAFS spectra of pentacene for the first monolayer and the crystalline films reflecting differences in the electronic coupling and the molecular orientation. Moreover, such characteristic π ∗-signatures were used to monitor in situ the film evolution upon deposition indicating an immediate formation of crystalline islands on top of a chemisorbed wetting layer.

  12. t2 g-orbital model on a honeycomb lattice: Application to the antiferromagnet SrRu 2O 6

    Science.gov (United States)

    Wang, Da; Wang, Wan-Sheng; Wang, Qiang-Hua

    2015-08-01

    Motivated by the recent discovery of high-temperature antiferromagnet SrRu2O6 [Hiley et al., Angew. Chem. Int. Ed. 53, 4423 (2014);, 10.1002/anie.201310110 Tian et al., arXiv:1504.03642] and its potential to be the parent of a new superconductor upon doping, we construct a minimal t2 g-orbital model on a honeycomb lattice to simulate its low-energy band structure. Local Coulomb interaction is taken into account through both random phase approximation and mean-field theory. Experimentally observed antiferromagnetic order is obtained in both approximations. In addition, our theory predicts that the magnetic moments on three t2 g-orbitals are noncollinear as a result of the strong spin-orbit coupling of Ru atoms.

  13. Synchrotron Based Structural Investigations of Mass-Selected PtxGd Nanoparticles and a Gd/Pt(111) Single Crystal for Electrochemical Oxygen Reduction

    DEFF Research Database (Denmark)

    Pedersen, Anders Filsøe; Velazquez-Palenzuela, Amado Andres; Masini, Federico;

    2015-01-01

    polycrystalline Pt5Gd2. In this work, we present the experimental results of mass-selected PtxGd nanoparticles synthesized by gas aggregation after sputtering of an alloy target in an ultrahigh vacuum (UHV)3. PtxGd nanoparticles with nominal sizes of 3, 5, 7, and 9 nm were selected using time-of-flight mass...... filtering and deposited on glassy carbon (GC) disk electrodes. Rotating ring disk electrode (RRDE) measurements in 0.1 M HClO4 were used to measure the activity in comparison to pure Pt 4. The ORR specific activity increases with the nanoparticle size; a maximum mass activity is achieved with the 7 nm...... the Oxygen Electroreduction Activity of Mass-Selected Platinum Nanoparticles. Angew. Chem. Int. Ed. 51, 4641–4643 (2012)....

  14. Computational Exploration of Rh(III)/Rh(V) and Rh(III)/Rh(I) Catalysis in Rhodium(III)-Catalyzed C-H Activation Reactions of N-Phenoxyacetamides with Alkynes.

    Science.gov (United States)

    Yang, Yun-Fang; Houk, K N; Wu, Yun-Dong

    2016-06-01

    The selective rhodium-catalyzed functionalization of arenes is greatly facilitated by oxidizing directing groups that act both as directing groups and internal oxidants. We report density functional theory (B3LYP and M06) investigations on the mechanism of rhodium(III)-catalyzed redox coupling reaction of N-phenoxyacetamides with alkynes. The results elucidated the role of the internal oxidizing directing group, and the role of Rh(III)/Rh(I) and Rh(III)/Rh(V) catalysis of C-H functionalizations. A novel Rh(III)-Rh(V)-Rh(III) cycle successfully rationalizes recent experimental observations by Liu and Lu et al. ( Liu , G. Angew. Chem. Int. Ed. 2013 , 52 , 6033 ) on the reactions of N-phenoxyacetamides with alkynes in different solvents. Natural Bond Orbital (NBO) analysis confirms the identity of Rh(V) intermediate in the catalytic cycle. PMID:27177448

  15. Proton-stabilized three-dimensional anionic framework in H[Zn6O2(BO3)3].

    Science.gov (United States)

    Massa, Werner; Yakubovich, Olga V; Dimitrova, Olga V

    2006-12-01

    A three-dimensional anionic framework built up from [ZnO4] tetrahedra and planar [BO3] groups, stabilized by H atoms, has been found for hydrogen zinc oxide borate, H[Zn6O2(BO3)3]. Boron and one of the borate O atoms are on 18e (2) positions. Triple units of [ZnO4] tetrahedra sharing a common oxygen vertex on a 12c (3) site and strong asymmetrical linear hydrogen bonds with the H atom [on a 12c (3) position] disordered over a twofold axis are specific structural features of this zincoborate. There is evidence that the reported Zn4O(BO3)2 [Harrison, Gier & Stuky (1993). Angew. Chem. Int. Ed. Engl. 32, 724-726] corresponds to this structure. PMID:17148884

  16. Evaluation of Meso-NH and WRF/CHEM simulated gas and aerosol chemistry over Europe based on hourly observations

    Science.gov (United States)

    Berger, A.; Barbet, C.; Leriche, M.; Deguillaume, L.; Mari, C.; Chaumerliac, N.; Bègue, N.; Tulet, P.; Gazen, D.; Escobar, J.

    2016-07-01

    Gas chemistry and aerosol chemistry of 10 km-resolution mesoscale models Meso-NH and WRF/CHEM were evaluated on three cases over Europe. These one-day duration cases were selected from Freney et al. (2011) and occurred on contrasted meteorological conditions and at different seasons: a cyclonic circulation with a well-marked frontal zone on winter, an anti-cyclonic situation with local storm precipitations on summer and a cold front in the northwest of Europe associated to a convergence of air masses over eastern Europe and conflicting air masses over Spain and France on autumn. To assess the performance of the two models, surface hourly databases from observation stations over Europe were used, together with airborne measurements. For both models, the meteorological fields were in good agreement with the measurements for the three days. Winds presented the largest normalised mean bias integrated over all European stations for both models. Daily gas chemistry was reproduced with normalised mean biases between - 14 and 11%, a level of accuracy that is acceptable for policy support. The two models' performances were degraded during night-time quite likely due to the constant primary species emissions. The PM2.5 bulk mass concentration was overestimated by Meso-NH over Europe and slightly underestimated by WRF/CHEM. The absence of wet deposition in the models partly explains the local discrepancies with the observations. More locally, the systematic low mixing ratio of volatile organic compounds in the gas phase simulated by WRF/CHEM at three stations was correlated with the underestimation of OM (organic matter) mass in the aerosol phase. Moreover, this mass of OM was mainly composed of anthropogenic POAs (primary organic aerosols) in WRF/CHEM, suggesting a missing source for SOAs (secondary organic aerosols) mass in WRF/CHEM aerosol parameterisation. The contribution of OM was well simulated by Meso-NH, with a higher contribution for the summer case. For Meso

  17. Improving the security of electricity supply - report by a rapporteur ad int

    International Nuclear Information System (INIS)

    The storms 'Pyry' and 'Janika', which swept over Finland in October-November 2001, caused serious damages to the operability of electric systems and led to long-term and extensive interruptions in electricity supply especially in Pirkanmaa, Central Home, Poijat-Hame and in the Uusimaa region. Although the security of electricity supply in Finland has in general been on a high level, the needs of customers concerning the quality of electrical power are constantly growing, and the operational reliability of the distribution networks will thereby have to be developed. The Rapporteur ad int. appointed by the Ministry of Trade and Industry on 21 November 2001 considers that such a scheme complementing the price reduction under the Electricity Market Act should be set up that would require a fixed compensation from the distribution network operators in the case of non deliverance of electricity. The fixed compensation should be paid automatically for e.g. interruptions lasting over 12 hours. The sum would depend on the length of the interruption and on the customer's annual rate of the network service fee. The Rapporteur also gives a number of other recommendations for improving the situation. Each distribution network operator is to choose the means of improvement on a technical-economical basis. The required level in the design, construction, operation and maintenance of an electrical network should guarantee that the interruptions in electricity supply would not exceed six hours even in exceptional circumstances. Ensuring electrical safety is of prime importance in disturbance situations. Shortening the interruption times and improving the quality of electricity call for sustained investment planning and activities. The distribution network operators should draw up a ten-year action plan. including measures aiming to reduce interruptions and the related timetables. To be able to keep the interruption times short in extensive cases of disturbance, the distribution

  18. Fluor Chem Q凝胶成像分析系统在科研实验及教学中的应用%Application of FluorChem Q gels image acquisition and analysis system in scientific research and teaching

    Institute of Scientific and Technical Information of China (English)

    潘洪超; 唐丹阳

    2012-01-01

    凝胶成像分析在生物及医药研究中已成为越来越重要的研究手段,对先进的Fluor Chem Q凝胶成像分析系统应用进行了初步阐述,该仪器运用到教学实践当中,使科研工作者对凝胶成像仪有进一步的了解,同时使得学生初步了解该仪器,提高学生的实践运用能力,达到理论与实践相结合的目的。%Gel imaging analysis system in biological and medical research has become more and more important. This paper primarily elaborated the application of the advanced FluorChem Q gel imaging systems, which had been applied to practice in teaching. This inlroduction made scientific research workers further understanding thr FluorChem Q gel imaging systems, and made students preliminarily understand it's application. The students' practice skills were improved, and also achieve theory combined with practice in teaching.

  19. Performance of WRF-Chem over Indian region: Comparison with measurements

    Indian Academy of Sciences (India)

    Gaurav Govardhan; Ravi S Nanjundiah; S K Satheesh; K Krishnamoorthy; V R Kotamarthi

    2015-06-01

    The aerosol mass concentrations over several Indian regions have been simulated using the online chemistry transport model, WRF-Chem, for two distinct seasons of 2011, representing the pre-monsoon (May) and post-monsoon (October) periods during the Indo–US joint experiment ‘Ganges Valley Aerosol Experiment (GVAX)’. The simulated values were compared with concurrent measurements. It is found that the model systematically underestimates near-surface BC mass concentrations as well as columnar Aerosol Optical Depths (AODs) from the measurements. Examining this in the light of the model-simulated meteorological parameters, we notice the model overestimates both planetary boundary layer height (PBLH) and surface wind speeds, leading to deeper mixing and dispersion and hence lower surface concentrations of aerosols. Shortcoming in simulating rainfall pattern also has an impact through the scavenging effect. It also appears that the columnar AODs are influenced by the unrealistic emission scenarios in the model. Comparison with vertical profiles of BC obtained from aircraft-based measurements also shows a systematic underestimation by the model at all levels. It is seen that concentration of other aerosols, viz., dust and sea-salt are closely linked with meteorological conditions prevailing over the region. Dust is higher during pre-monsoon periods due to the prevalence of north-westerly winds that advect dust from deserts of west Asia into the Indo-Gangetic plain. Winds and rainfall influence sea-salt concentrations. Thus, the unrealistic simulation of wind and rainfall leads to model simulated dust and sea-salt also to deviate from the real values; which together with BC also causes underperformance of the model with regard to columnar AOD. It appears that for better simulations of aerosols over Indian region, the model needs an improvement in the simulation of the meteorology.

  20. Mixed waste treatment using the ChemChar thermolytic detoxification technique

    International Nuclear Information System (INIS)

    The diversity of mixed waste matrices contained at Department of Energy sites that require treatment preclude a single, universal treatment technology capable of handling sludges, solids, heterogeneous debris, aqueous and organic liquids and soils. Versatility of the treatment technology, volume reduction and containment of the radioactive component of the mixed waste streams are three criteria to be considered when evaluating potential treatment technologies. The ChemChar thermolytic detoxification process being developed under this R and D contract is a thermal, chemically reductive technology that converts the organic portion of a mixed waste stream to an energy-rich synthesis gas while simultaneously absorbing volatile inorganic species (metals and acid gases) on a macroporous, carbon-based char. The latter is mixed with the waste stream prior to entering the reactor. Substoichiometric amounts of oxidant are fed into the top portion of the cylindrical reactor generating a thin, radial thermochemical reaction zone. This zone generates all the necessary heat to promote the highly endothermic reduction of the organic components in the waste in the lower portion of the reactor, producing, principally, hydrogen and carbon monoxide. The solid by-product is a regenerated carbon char that, depending on the inorganic loading, is capable for reuse. The in situ scrubbing of contaminants by the char within the reactor coupled with a char filter for final polishing produce an exceptionally clean synthesis gas effluent suitable for on-site generation of heat, steam or electricity. Despite the elevated temperatures in the thermochemical reaction zone, the reductive nature of the process precludes formation of nitrogen oxides and halogenated organic compound by-products

  1. How wild is your model fire? Constraining WRF-Chem wildfire smoke simulations with satellite observations

    Science.gov (United States)

    Fischer, E. V.; Ford, B.; Lassman, W.; Pierce, J. R.; Pfister, G.; Volckens, J.; Magzamen, S.; Gan, R.

    2015-12-01

    Exposure to high concentrations of particulate matter (PM) present during acute pollution events is associated with adverse health effects. While many anthropogenic pollution sources are regulated in the United States, emissions from wildfires are difficult to characterize and control. With wildfire frequency and intensity in the western U.S. projected to increase, it is important to more precisely determine the effect that wildfire emissions have on human health, and whether improved forecasts of these air pollution events can mitigate the health risks associated with wildfires. One of the challenges associated with determining health risks associated with wildfire emissions is that the low spatial resolution of surface monitors means that surface measurements may not be representative of a population's exposure, due to steep concentration gradients. To obtain better estimates of ambient exposure levels for health studies, a chemical transport model (CTM) can be used to simulate the evolution of a wildfire plume as it travels over populated regions downwind. Improving the performance of a CTM would allow the development of a new forecasting framework that could better help decision makers estimate and potentially mitigate future health impacts. We use the Weather Research and Forecasting model with online chemistry (WRF-Chem) to simulate wildfire plume evolution. By varying the model resolution, meteorology reanalysis initial conditions, and biomass burning inventories, we are able to explore the sensitivity of model simulations to these various parameters. Satellite observations are used first to evaluate model skill, and then to constrain the model results. These data are then used to estimate population-level exposure, with the aim of better characterizing the effects that wildfire emissions have on human health.

  2. Evolution et perspectives de la demande intérieure de corps gras en Afrique subsaharienne

    Directory of Open Access Journals (Sweden)

    Hirsch Robert

    2000-03-01

    Full Text Available Si les corps gras peuvent constituer l’une des clés de voûte de l’agriculture de certains pays émergents (Malaisie, Brésil, ils ne font l’objet, en Afrique, que de très peu d’intérêt. Rarement cités parmi les produits de première nécessité, éclatés entre différentes filières (palme, coton, arachide, les corps gras ne se situent au cœur des préoccupations des décideurs qu’en période de crise tandis que, de leur côté, les bailleurs de fonds ne leur portent qu’une attention modérée, le plus souvent ponctuelle et sans vision stratégique. Dans les années 60, c’est-à-dire à l’époque des indépendances, le continent africain disposait pourtant de sérieux atouts, puisqu’il dominait largement le marché mondial des produits du palmier (huile et palmistes et était encore bien placé sur celui des produits de l’arachide (huile et tourteaux. Des pays comme le Nigeria ou l’ex-Zaïre disposaient d’un potentiel alors jugé prometteur, apte à conforter leurs positions commerciales. Mais le pétrole pour le premier et les crises politiques à répétition pour le second ont assez rapidement réduit à néant les espoirs que l’on pouvait légitimement placer dans l’agriculture de ces pays. Si, à partir des années 70, le soja, en Amérique latine, et l’huile de palme, en Asie du Sud-est, ont réussi à s’imposer sur un marché mondial en pleine expansion, l’Afrique, qui n’était dépourvue ni de terres, ni de main-d’œuvre, ni des acquis d’une recherche globalement performante, s’est repliée sur elle-même. Les investissements non négligeables, réalisés dans un premier temps en Côte d’Ivoire, au Cameroun et dans quelques autres pays, étaient financés par les États eux-mêmes à travers des sociétés publiques sous-capitalisées et rarement gérées dans une perspective de maîtrise des coûts, à qui était assigné un objectif prioritaire de satisfaction des besoins int

  3. Closure on the single scattering albedo in the WRF-Chem framework using data from the MILAGRO campaign

    OpenAIRE

    J. C. Barnard; J. D. Fast; G. Paredes-Miranda; Arnott, W.P.

    2009-01-01

    Data from the MILAGRO field campaign, which took place in the Mexico City Metropolitan Area (MCMA) during March 2006, is used to perform a closure experiment between aerosol chemical properties and aerosol optical properties. Measured aerosol chemical properties, obtained from the MILAGRO T1 site, are fed to two different "chemical to optical properties" modules. One module uses a sectional approach and is identical to that used in the WRF-Chem model, while the other is based on a m...

  4. Quantifying the sub-grid variability of trace gases and aerosols based on WRF-Chem simulations

    OpenAIRE

    Y. Qian; W. I. Gustafson Jr.; J. D. Fast

    2010-01-01

    One fundamental property and limitation of grid based models is their inability to identify spatial details smaller than the grid cell size. While decades of work have gone into developing sub-grid treatments for clouds and land surface processes in climate models, the quantitative understanding of sub-grid processes and variability for aerosols and their precursors is much poorer. In this study, WRF-Chem is used to simulate the trace gases and aerosols over central Mexico during the 2006 MIL...

  5. Changes of the Chemistry Teacher Candidates’ Attitudes towards and Views about Information and Communication Technologies: ChemBioDraw Application

    OpenAIRE

    Paşa, Salih; BOLAT, Yusuf İslam; KARATAŞ, Faik Özgür

    2016-01-01

    The aim of this study is to determine technology attitudes of chemistry teacher candidates by using ChemBioDraw software as computer assisted teaching material in Organic Structural Analysis class for planned four weeks. Furthermore, it was also intended students thoughts about using technology and visualization software in education. This study was carried out as applicable for the mixed method approach. In this regard, a pre- and post-test single group experimental design was administrated ...

  6. A global comparison of GEOS-Chem predicted and remotely-sensed mineral dust aerosol optical depth

    OpenAIRE

    Johnson, Matthew S.; Nicholas Meskhidze; Kiliyanpilakkil V Praju

    2012-01-01

    Dust aerosol optical depth (AOD) and vertical distribution of aerosol extinction predicted by a global chemical transport model (GEOS-Chem) are compared to space-borne data from the Moderate-resolution Imaging Spectroradiometer (MODIS), Multi-Angle Imaging SpectroRadiometer (MISR), and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) for March 2009 to February 2010. Model-predicted and remotely-sensed AOD/aerosol extinction profiles are compared over six regions whe...

  7. CHEM2D-OPP: A new linearized gas-phase ozone photochemistry parameterization for high-altitude NWP and climate models

    Directory of Open Access Journals (Sweden)

    J. P. McCormack

    2006-01-01

    Full Text Available The new CHEM2D-Ozone Photochemistry Parameterization (CHEM2D-OPP for high-altitude numerical weather prediction (NWP systems and climate models specifies the net ozone photochemical tendency and its sensitivity to changes in ozone mixing ratio, temperature and overhead ozone column based on calculations from the CHEM2D interactive middle atmospheric photochemical transport model. We evaluate CHEM2D-OPP performance using both short-term (6-day and long-term (1-year stratospheric ozone simulations with the prototype high-altitude NOGAPS-ALPHA forecast model. An inter-comparison of NOGAPS-ALPHA 6-day ozone hindcasts for 7 February 2005 with ozone photochemistry parameterizations currently used in operational NWP systems shows that CHEM2D-OPP yields the best overall agreement with both individual Aura Microwave Limb Sounder ozone profile measurements and independent hemispheric (10°–90° N ozone analysis fields. A 1-year free-running NOGAPS-ALPHA simulation using CHEM2D-OPP produces a realistic seasonal cycle in zonal mean ozone throughout the stratosphere. We find that the combination of a model cold temperature bias at high latitudes in winter and a warm bias in the CHEM2D-OPP temperature climatology can degrade the performance of the linearized ozone photochemistry parameterization over seasonal time scales despite the fact that the parameterized temperature dependence is weak in these regions.

  8. Inclusion of ash and SO2 emissions from volcanic eruptions in WRF-Chem: development and some applications

    Directory of Open Access Journals (Sweden)

    M. Stuefer

    2013-04-01

    Full Text Available We describe a new functionality within the Weather Research and Forecasting (WRF model with coupled Chemistry (WRF-Chem that allows simulating emission, transport, dispersion, transformation and sedimentation of pollutants released during volcanic activities. Emissions from both an explosive eruption case and a relatively calm degassing situation are considered using the most recent volcanic emission databases. A preprocessor tool provides emission fields and additional information needed to establish the initial three-dimensional cloud umbrella/vertical distribution within the transport model grid, as well as the timing and duration of an eruption. From this source condition, the transport, dispersion and sedimentation of the ash cloud can be realistically simulated by WRF-Chem using its own dynamics and physical parameterization as well as data assimilation. Examples of model applications include a comparison of tephra fall deposits from the 1989 eruption of Mount Redoubt (Alaska and the dispersion of ash from the 2010 Eyjafjallajökull eruption in Iceland. Both model applications show good coincidence between WRF-Chem and observations.

  9. Inclusion of Ash and SO2 emissions from volcanic eruptions in WRF-CHEM: development and some applications

    Directory of Open Access Journals (Sweden)

    S. Peckham

    2012-09-01

    Full Text Available We describe a new functionality within the Weather Research and Forecasting model with coupled Chemistry (WRF-Chem that allows simulating emission, transport, dispersion, transformation and sedimentation of pollutants released during volcanic activities. Emissions from both an explosive eruption case and relatively calm degassing situation are considered using the most recent volcanic emission databases. A preprocessor tool provides emission fields and additional information needed to establish the initial three-dimensional cloud umbrella/vertical distribution within the transport model grid, as well as the timing and duration of an eruption. From this source condition, the transport, dispersion and sedimentation of the ash-cloud can be realistically simulated by WRF-Chem using its own dynamics, physical parameterization as well as data assimilation. Examples of model validation include a comparison of tephra fall deposits from the 1989 eruption of Mount Redoubt (Alaska, and the dispersion of ash from the 2010 Eyjafjallajökull eruption in Iceland. Both model applications show good coincidence between WRF-Chem and observations.

  10. Impacto psicológico. El estrés : causas, consecuencias y soluciones : intérprete de conferencias frente a intérprete en los servicios públicos

    OpenAIRE

    Márquez Olalla, Juan Francisco

    2016-01-01

    En pleno desarrollo del siglo XXI, el estrés laboral supone uno de las mayores preocupaciones para la sociedad. En la interpretación sucede lo mismo. Los intérpretes se ven afectados durante su labor de intercambio lingüístico debido a estresores que les llevan a ejercer bajo presión. Ello les lleva a buscar soluciones para que el resultado final de su trabajo sea óptimo y no les cause un desgaste en la salud. El objetivo principal de este proyecto de investigación es estudiar y analizar ...

  11. Bases del diseño curricular para la formación de traductores e intérpretes en Turquía

    OpenAIRE

    Aka, Özlem

    2015-01-01

    La presente tesis doctoral presenta algunas bases para el diseño curricular para la formación de traductores e intérpretes en Turquía. Consta de tres partes. La primera parte se trata de la formación de traductores e intérpretes en Europa y el proceso de implantación del EEES. En la segunda parte, se presentan bases pedagógicas para la formación de traductores e intérpretes y se expone una propuesta del diseño curricular de grado para la formación de traductores e intérpretes en Turqu...

  12. Modeling of the chemical composition of fine particulate matter: Development and performance assessment of EASYWRF-Chem

    Science.gov (United States)

    Mendez, M.; Lebègue, P.; Visez, N.; Fèvre-Nollet, V.; Crenn, V.; Riffault, V.; Petitprez, D.

    2016-03-01

    The European emission Adaptation SYstem for the WRF-Chem model (EASYWRF-Chem) has been developed to generate chemical information supporting the WRF-Chem requirements from any emission inventory based on the CORINAIR methodology. Using RADM2 and RACM2 mechanisms, "emission species" are converted into "model species" thanks to the SAPRC methodology for gas phase pollutant and the PM10 and PM2.5 fractions. Furthermore, by adapting US EPA PM2.5 profiles, the processing of aerosol chemical speciation profiles separates the unspeciated PM2.5 emission into five chemical families: sulfates, nitrates, elemental carbon, organic aerosol and unspeciated aerosol. The evaluation of the model has been performed by separately comparing model outcomes with (i) meteorological measurements; (ii) NO2, O3, PM10 and PM2.5 mass concentrations from the regional air quality monitoring network; (iii) hourly-resolved data from four field campaign measurements, in winter and in summer, on two sites in the French northern region. In the latter, a High Resolution - Time of Flight - Aerosol Mass Spectrometer (HR-ToF-AMS) provided non-refractory PM1 concentrations of sulfate, nitrate and ammonium ions as well as organic matter (OM), while an aethalometer provided black carbon (BC) concentrations in the PM2.5 fraction. Meteorological data (temperature, wind, relative humidity) are well simulated for all the time series data except for specific events as wind direction changes or rainfall. For particulate matter, results are presented by considering firstly the total mass concentration of PM2.5 and PM10. EASYWRF-Chem simulations overestimated the PM10 mass concentrations by + 22% and + 4% for summer and winter periods respectively, whereas for the finer PM2.5 fraction, mass concentrations were overestimated by + 20% in summer and underestimated by - 13% in winter. Simulated sulfate concentrations were underestimated and nitrate concentrations were overestimated but hourly variations were well

  13. Calibration of the Fluorine, Chlorine and Hydrogen Content of Apatites With the ChemCam LIBS Instrument

    Science.gov (United States)

    Meslin, P.-Y.; Cicutto, L.; Forni, O.; Drouet, C.; Rapin, W.; Nachon, M.; Cousin, A.; Blank, J. G.; McCubbin, F. M.; Gasnault, O.; Newsom, H.; Mangold, N.; Schroeder, S.; Sautter, V.; Maurice, S.; Wiens, R. C.

    2016-01-01

    Determining the composition of apatites is important to understand the behavior of volatiles during planetary differentiation. Apatite is an ubiquitous magmatic mineral in the SNC meteorites. It is a significant reservoir of halogens in these meteorites and has been used to estimate the halogen budget of Mars. Apatites have been identified in sandstones and pebbles at Gale crater by ChemCam, a Laser-Induced Breakdown Spectroscometer (LIBS) instrument onboard the Curiosity rover. Their presence was inferred from correlations between calcium, fluorine (using the CaF molecular band centered near 603 nm, whose detection limit is much lower that atomic or ionic lines and, in some cases, phosphorus (whose detection limit is much larger). An initial quantification of fluorine, based on fluorite (CaF2)/basalt mixtures and obtained at the LANL laboratory, indicated that the excess of F/Ca (compared to the stoichiometry of pure fluorapatites) found on Mars in some cases could be explained by the presence of fluorite. Chlorine was not detected in these targets, at least above a detection limit of 0.6 wt% estimated from. Fluorapatite was later also detected by X-ray diffraction (with CheMin) at a level of approx.1wt% in the Windjana drill sample (Kimberley area), and several points analyzed by ChemCam in this area also revealed a correlation between Ca and F. The in situ detection of F-rich, Cl-poor apatites contrasts with the Cl-rich, F-poor compositions of apatites found in basaltic shergottites and in gabbroic clasts from the martian meteorite NWA 7034, which were also found to be more Cl-rich than apatites from basalts on Earth, the Moon, or Vesta. The in situ observations could call into question one of the few possible explanations brought forward to explain the SNC results, namely that Mars may be highly depleted in fluorine. The purpose of the present study is to refine the calibration of the F, Cl, OH and P signals measured by the ChemCam LIBS instrument, initiated

  14. Chemo-stratigraphy in the Murray Formation Using ChemCam

    Science.gov (United States)

    Blaney, D. L.; Anderson, R. B.; Bridges, N.; Bridges, J.; Calef, F. J., III; Clegg, S. M.; Le Deit, L.; Fisk, M. R.; Forni, O.; Gasnault, O.; Kah, L. C.; Kronyak, R. E.; Lanza, N.; Lasue, J.; Mangold, N.; Maurice, S.; Milliken, R.; Ming, D. W.; Nachon, M.; Newsom, H. E.; Rapin, W.; Stack, K.; Sumner, D. Y.; Wiens, R. C.

    2015-12-01

    Curiosity has completed a detailed chemo-stratigraphy analysis at the Pahrump exposure of the Murray formation. In total >570 chemical measurements and supporting remote micro images to classify texturally were collected. Chemical trends with both stratigraphic position and with texture were evaluated. From these data emerges a complex aqueous history where sediments have interacted with fluids with variable chemistry in distinct episodes. The ChemCam data collected at the nearby "Garden City" (GC) vein complex provides constraints on the chemical evolution of the Pahrump. GC is thought be stratigraphically above the Pahrump outcrop. Fluids producing the veins likely also migrated through the Pahrump sediments. Multiple episodes of fluids are evident at GC, forming distinct Ca sulfate, F-rich, enhanced MgO, and FeO-rich veins. These different fluid chemistries could be the result of distinct fluids migrating through the section from a distance with a pre-established chemical signature, fluids locally evolved from water rock interactions, or both. Texturally rocks have been classified into two distinct categories: fine grained or as cross-bedded sandstones. The sandstones have significantly lower SiO2, Al2O3, and K2O and higher FeO, and CaO. Fine grained rocks have further been sub-classified as resistant and recessive with other textural features such as laminations and pits noted.The strongest chemical trend in the fine-grained sandstones shows enhancements in MgO and FeO in erosion-resistant materials compared to fine grained recessive units, suggesting that increased abundance of Mg- and/or iron-rich cements may provide additional strength. The MgO and FeO variations with texture are independent of stratigraphic locations (e.g resistant material at both the bottom and top of the outcrop both are enhanced in MgO and FeO). The presence of the GC MgO and FeO rich veins provides additional evidence for fluids rich in these elements were present in the outcrop. Other

  15. Pour une intégration du genre par les sciences de l’information et de la communication

    OpenAIRE

    Julliard, Virginie

    2012-01-01

    Il s’agira ici de montrer combien l’intégration du genre en sciences de l’information et de la communication est productive. Le genre est usuellement compris comme la construction socio-historique de la différence des sexes. Les études l’utilisent au moins de deux manières : d’abord comme système normatif sur lequel il est nécessaire de produire des connaissances, ensuite comme outil conceptuel permettant de questionner d’autres objets sur la manière dont est conçue la différence sexuelle. Ai...

  16. L'intégration du hors-travail dans la gestion des ressources humaines : entre paternalisme et empowerment

    OpenAIRE

    De Bry, Françoise; Ollier-Malaterre, Ariane

    2006-01-01

    Les pratiques de ressources humaines dites de Work-Life (c'est-à-dire qui visent à l'harmonisation travail-hors-travail), développées principalement dans les entreprises anglo-saxonnes, intègrent la vie hors-travail des salariés. Sur le plan théorique, ces pratiques se lisent comme une réponse organisationnelle au hors-travail, pouvant relever de deux modèles de management bien distincts : le paternalisme et l'empowerment (capacitation). Sur la base d'une mise en perspective historique de ces...

  17. Intégration de la Ventilation Naturelle en Façade de Bâtiment

    OpenAIRE

    Migneron, Jean-Philippe

    2010-01-01

    Les nouvelles tendances dans le monde de la construction se tournent vers le bâtiment écoénergétique. En Amérique du Nord, les nouvelles normes en matière de développement durable deviennent choses communes. Parmi les multiples possibilités d'augmentation de l'efficacité des édifices, il est maintenant reconnu que l'utilisation de la ventilation naturelle permet de diminuer la consommation et d'accroître la satisfaction des occupants. L'intégration de la fenestration et des ouvertures d'aérat...

  18. Intèrpret d'experiències interactives basades en geo-localització per a sistemes Android

    OpenAIRE

    Pérez Sandonís, Jordi

    2015-01-01

    Aquest treball presenta l'intèrpret d'experiències interactives basades en geolocalització "Gien" pel sistema operatiu mòbil Android. "Gien" pretén interpretar i interactuar amb aquestes experiències de diferents caires i donar solució al problema dels desenvolupadors d'experiències que han de programar una aplicació diferent per a cadascuna d'elles. "Gien" és similar a un navegador web amb la diferència que aquesta aplicació no interpreta documents web sinó un altre tipus de fitxer que repre...

  19. Un modèle de programmation intégrant classes, événements et aspects

    OpenAIRE

    Núñez, Angel

    2011-01-01

    Le paradigme de la programmation par objets (PPO) est devenu le paradigme de programmation le plus utilisé. La programmation événementielle (PE) et la programmation par aspects (PPA) complètent la PPO en comblant certaines de ses lacunes lors de la construction de logiciels complexes. Les applications actuelles combinent ainsi les trois paradigmes. Toutefois, la POO, la PE et la POA ne sont pas encore bien intégrées. Leurs concepts sous-jacents sont en général fournis sous la forme de constru...

  20. A Case Study in Competitive Technical and Market Intelligence Support and Lessons Learned for the uChemLab LDRD Grand Challenge Project; TOPICAL

    International Nuclear Information System (INIS)

    The(mu)ChemLab(trademark) Laboratory Directed Research and Development (LDRD) Grand Challenge project began in October 1996 and ended in September 2000. The technical managers of the(mu)ChemLab(trademark) project and the LDRD office, with the support of a consultant, conducted a competitive technical and market demand intelligence analysis of the(mu)ChemLab(trademark). The managers used this knowledge to make project decisions and course adjustments. CTI/MDI positively impacted the project's technology development, uncovered potential technology partnerships, and supported eventual industry partner contacts. CTI/MDI analysis is now seen as due diligence and the(mu)ChemLab(trademark) project is now the model for other Sandia LDRD Grand Challenge undertakings. This document describes the CTI/MDI analysis and captures the more important ''lessons learned'' of this Grand Challenge project, as reported by the project's management team

  1. The Second Data Release of the INT Photometric H\\alpha\\ Survey of the Northern Galactic Plane (IPHAS DR2)

    CERN Document Server

    Barentsen, Geert; Drew, J E; González-Solares, E A; Greimel, R; Irwin, M J; Miszalski, B; Ruhland, C; Groot, P; Mampaso, A; Sale, S E; Henden, A A; Aungwerojwit, A; Barlow, M J; Carter, P J; Corradi, R L M; Drake, J J; Eislöffel, J; Fabregat, J; Gänsicke, B T; Fusillo, N P Gentile; Greiss, S; Hales, A S; Hodgkin, S; Huckvale, L; Irwin, J; King, R; Knigge, C; Kupfer, T; Lagadec, E; Lennon, D J; Lewis, J R; Mohr-Smith, M; Morris, R A H; Naylor, T; Parker, Q A; Phillipps, S; Pyrzas, S; Raddi, R; Roelofs, G H A; Rodríguez-Gil, P; Sabin, L; Scaringi, S; Steeghs, D; Suso, J; Tata, R; Unruh, Y C; van Roestel, J; Viironen, K; Vink, J S; Walton, N A; Wright, N J; Zijlstra, A A

    2014-01-01

    The INT/WFC Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS) is a 1800 square degrees imaging survey covering Galactic latitudes |b| < 5 deg and longitudes l = 30 to 215 deg in the r, i and H\\alpha\\ filters using the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) in La Palma. We present the first quality-controlled and globally-calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92% of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec/pixel) and to a mean 5\\sigma-depth of 21.2 (r), 20.0 (i) and 20.3 (H\\alpha) in the Vega magnitude system. We explain the data reduction and quality control procedures, describe and test the global re-calibration, and detail the construction of the new catalogue. We show that the new calibration is accurate to 0.03 mag (rms) and recommend a series of quality criteria to select the most rel...

  2. Application of WRF/Chem over East Asia: Part I. Model evaluation and intercomparison with MM5/CMAQ

    Science.gov (United States)

    Zhang, Yang; Zhang, Xin; Wang, Litao; Zhang, Qiang; Duan, Fengkui; He, Kebin

    2016-01-01

    In this work, the application of the online-coupled Weather Research and Forecasting model with chemistry (WRF/Chem) version 3.3.1 is evaluated over East Asia for January, April, July, and October 2005 and compared with results from a previous application of an offline model system, i.e., the Mesoscale Model and Community Multiple Air Quality modeling system (MM5/CMAQ). The evaluation of WRF/Chem is performed using multiple observational datasets from satellites and surface networks in mainland China, Hong Kong, Taiwan, and Japan. WRF/Chem simulates well specific humidity (Q2) and downward longwave and shortwave radiation (GLW and GSW) with normalized mean biases (NMBs) within 24%, but shows moderate to large biases for temperature at 2-m (T2) (NMBs of -9.8% to 75.6%) and precipitation (NMBs of 11.4-92.7%) for some months, and wind speed at 10-m (WS10) (NMBs of 66.5-101%), for all months, indicating some limitations in the YSU planetary boundary layer scheme, the Purdue Lin cloud microphysics, and the Grell-Devenyi ensemble scheme. WRF/Chem can simulate the column abundances of gases reasonably well with NMBs within 30% for most months but moderately to significantly underpredicts the surface concentrations of major species at all sites in nearly all months with NMBs of -72% to -53.8% for CO, -99.4% to -61.7% for NOx, -84.2% to -44.5% for SO2, -63.9% to -25.2% for PM2.5, and -68.9% to 33.3% for PM10, and aerosol optical depth in all months except for October with NMBs of -38.7% to -16.2%. The model significantly overpredicts surface concentrations of O3 at most sites in nearly all months with NMBs of up to 160.3% and NO3- at the Tsinghua site in all months. Possible reasons for large underpredictions include underestimations in the anthropogenic emissions of CO, SO2, and primary aerosol, inappropriate vertical distributions of emissions of SO2 and NO2, uncertainties in upper boundary conditions (e.g., for O3 and CO), missing or inaccurate model representations (e

  3. Comparison of Predicted pKa Values for Some Amino-Acids, Dipeptides and Tripeptides, Using COSMO-RS, ChemAxon and ACD/Labs Methods Comparaison des valeurs de pKa de quelques acides aminés, dipeptides et tripeptides, prédites en utilisant les méthodes COSMO-RS, ChemAxon et ACD/Labs

    Directory of Open Access Journals (Sweden)

    Toure O.

    2013-05-01

    données internes contenant des structures chimiques ainsi que leurs valeurs expérimentales de pKa. L’écart-type moyen des valeurs prédites vaut respectivement 0,596 pour la méthode COSMO-RS, 0,445 pour la méthode ChemAxon et 0,490 pour la méthode ACD/Labs. Au vu de ces résultats, la méthode COSMO-RS apparaît comme une méthode prometteuse pour prédire les valeurs de pKa de molécules d’intérêt dans l’industrie alimentaire pour lesquelles peu de données de pKa sont disponibles comme les peptides, d’autant plus que les méthodes ACD/Labs et ChemAxon ont été paramétrées en utilisant un grand nombre de données expérimentales (incluant certaines des molécules étudiées dans cet article alors que la méthode COSMO-RS a été utilisée d’un point de vue purement prédictif. L’objectif final de cette étude est d’utiliser ces valeurs de pKa dans un modèle thermodynamique prédictif pour des produits d’intérêt dans l’industrie alimentaire. Pour ce faire, les effets de certains facteurs (comme le traitement des conformations dans les calculs COSMO-RS,l’infuence de la force ionique pouvant influencer la comparaison entre les données expérimentales et les données prédites, seront discutés.

  4. Twelve-month, 12 km resolution North American WRF-Chem v3.4 air quality simulation: performance evaluation

    Directory of Open Access Journals (Sweden)

    C. W. Tessum

    2015-04-01

    Full Text Available We present results from and evaluate the performance of a 12-month, 12 km horizontal resolution year 2005 air pollution simulation for the contiguous United States using the WRF-Chem (Weather Research and Forecasting with Chemistry meteorology and chemical transport model (CTM. We employ the 2005 US National Emissions Inventory, the Regional Atmospheric Chemistry Mechanism (RACM, and the Modal Aerosol Dynamics Model for Europe (MADE with a volatility basis set (VBS secondary aerosol module. Overall, model performance is comparable to contemporary modeling efforts used for regulatory and health-effects analysis, with an annual average daytime ozone (O3 mean fractional bias (MFB of 12% and an annual average fine particulate matter (PM2.5 MFB of −1%. WRF-Chem, as configured here, tends to overpredict total PM2.5 at some high concentration locations and generally overpredicts average 24 h O3 concentrations. Performance is better at predicting daytime-average and daily peak O3 concentrations, which are more relevant for regulatory and health effects analyses relative to annual average values. Predictive performance for PM2.5 subspecies is mixed: the model overpredicts particulate sulfate (MFB = 36%, underpredicts particulate nitrate (MFB = −110% and organic carbon (MFB = −29%, and relatively accurately predicts particulate ammonium (MFB = 3% and elemental carbon (MFB = 3%, so that the accuracy in total PM2.5 predictions is to some extent a function of offsetting over- and underpredictions of PM2.5 subspecies. Model predictive performance for PM2.5 and its subspecies is in general worse in winter and in the western US than in other seasons and regions, suggesting spatial and temporal opportunities for future WRF-Chem model development and evaluation.

  5. Lightning NOx emissions over the USA constrained by TES ozone observations and the GEOS-Chem model

    Directory of Open Access Journals (Sweden)

    K. E. Pickering

    2010-01-01

    Full Text Available Improved estimates of NOx from lightning sources are required to understand tropospheric NOx and ozone distributions, the oxidising capacity of the troposphere and corresponding feedbacks between chemistry and climate change. In this paper, we report new satellite ozone observations from the Tropospheric Emission Spectrometer (TES instrument that can be used to test and constrain the parameterization of the lightning source of NOx in global models. Using the National Lightning Detection (NLDN and the Long Range Lightning Detection Network (LRLDN data as well as the HYPSLIT transport and dispersion model, we show that TES provides direct observations of ozone enhanced layers downwind of convective events over the USA in July 2006. We find that the GEOS-Chem global chemistry-transport model with a parameterization based on cloud top height, scaled regionally and monthly to OTD/LIS (Optical Transient Detector/Lightning Imaging Sensor climatology, captures the ozone enhancements seen by TES. We show that the model's ability to reproduce the location of the enhancements is due to the fact that this model reproduces the pattern of the convective events occurrence on a daily basis during the summer of 2006 over the USA, even though it does not well represent the relative distribution of lightning intensities. However, this model with a value of 6 Tg N/yr for the lightning source (i.e.: with a mean production of 260 moles NO/Flash over the USA in summer underestimates the intensities of the ozone enhancements seen by TES. By imposing a production of 520 moles NO/Flash for lightning occurring in midlatitudes, which better agrees with the values proposed by the most recent studies, we decrease the bias between TES and GEOS-Chem ozone over the USA in July 2006 by 40%. However, our conclusion on the strength of the lightning source of NOx is limited by the fact that the contribution from the stratosphere is underestimated in the GEOS-Chem simulations.

  6. Validation of WRF/Chem model and sensitivity of chemical mechanisms to ozone simulation over megacity Delhi

    Science.gov (United States)

    Gupta, Medhavi; Mohan, Manju

    2015-12-01

    Regional Chemical transport models (CTM) are used extensively for modeling of Ozone concentration. WRF/Chem is one such CTM that includes various chemical mechanisms and is used for simulation of Ozone and other pollutant concentration at desired time step. This study focuses on the robustness of WRF/Chem simulated Ozone concentrations over a sub tropical urban airshed of megacity Delhi. Detailed analysis has been presented for the veracity of two different chemical mechanisms namely; Carbon Bond Mechanism (CBMZ) and Regional Atmospheric Chemical Model (RACM). It was observed that simulated Ozone concentrations are better predicted with CBMZ mechanism and is highly sensitive to the rate constants. The Ozone concentrations are analyzed for precursors such as Oxides of Nitrogen (NOx) and Carbon-monoxide (CO) as well as temperature considering their strong dependence on Ozone formation. A consistent positive correlation between Ozone concentration and temperature is noted whereas; NOx and CO show inverse relationship with Ozone. Further, Ozone concentration range vis-à-vis model performance is scrutinized. A poor model for low Ozone concentration levels is observed and a highly satisfactory for moderate Ozone concentration levels while satisfactory for higher Ozone levels. Despite of the limitations observed during model evaluation of Ozone predictions for low Ozone levels, it is concluded that WRF/Chem could effectively be applied for understanding its trends, tropospheric chemistry and air quality assessment for regulatory purposes at moderate Ozone concentration levels. Further, it is recommended that model implementation shall be made for policy decisions cautiously with due consideration to the magnitudes of Ozone levels present in the study domain and the performance measures in the specific concentration range.

  7. Simulation of the Dust Aerosol and its Climatic Effect over East Asia using WRF-Chem model

    Science.gov (United States)

    Chen, S.; Huang, J.; Zhao, C.; Qian, Y.; Ruby, L.

    2015-12-01

    WRF-Chem model is used to investigate the seasonal and inter-annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and its direct radiative forcing and climatic impact. A variety of in-situ measurements and satellite observations have been used to evaluate the simulation results. Generally, WRF-Chem reasonably reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions. In addition, the dust lifecycle and processes that control the seasonal and spatial variations of dust mass balance are investigated in seven sub-regions. Dust direct radiative forcing in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 9 and 2 W m-2, and TOA cooling of -5 and -8 W m-2, respectively. The ability of WRF-Chem to capture the measured features of dust optical and radiative properties and dust mass balance over East Asian provides confidence for future investigation of East Asia dust impact on regional or global climate. Over the Tibetan Plateau, dust modifies the atmospheric heating profiles and cloud properties, leading to a decrease of snowfall and hence snow coverage on the ground. These results are from a reduction of surface albedo and increased surface temperature, further accelerating snowmelt. This impact is smallest in summer, when the snow coverage is relative low. Over the East China-Korea-Japan regions, dust modifies the atmospheric heating profiles and cloud properties. Dust induces significant changes in the magnitudes and diurnal variations of surface temperature. Cloud liquid water content is also significantly impacted, as reflected in changes of cloud forcing at the top of the atmosphere (TOA) with a maximum in summer. The dust impacts on spatial distribution of precipitation and wind circulation are also investigated, showing distinct seasonality of dust impact on the regional climate over East Asia.

  8. Simulations of the Holuhraun eruption 2014 with WRF-Chem and evaluation with satellite and ground based SO2 measurements

    Science.gov (United States)

    Hirtl, Marcus; Arnold-Arias, Delia; Flandorfer, Claudia; Maurer, Christian; Mantovani, Simone; Natali, Stefano

    2016-04-01

    Volcanic eruptions, with gas or/and particle emissions, directly influence our environment, with special significance when they either occur near inhabited regions or are transported towards them. In addition to the well-known affectation of air traffic, with large economic impacts, the ground touching plumes can lead directly to an influence of soil, water and even to a decrease of air quality. The eruption of Holuhraun in August 2014 in central Iceland is the country's largest lava and gas eruption since the Lakagígar eruption in 1783. Nevertheless, very little volcanic ash was produced. The main atmospheric threat from this event was the SO2 pollution that frequently violated the Icelandic National Air Quality Standards in many population centers. However, the SO2 affectation was not limited to Iceland but extended to mainland Europe. The on-line coupled model WRF-Chem is used to simulate the dispersion of SO2 for this event that affected the central European regions. The volcanic emissions are considered in addition to the anthropogenic and biogenic ground sources at European scale. A modified version of WRF-Chem version 4.1 is used in order to use time depending injection heights and mass fluxes which were obtained from in situ observations. WRF-Chem uses complex gas- (RADM2) and aerosol- (MADE-SORGAM) chemistry and is operated on a European domain (12 km resolution), and a nested grid covering the Alpine region (4 km resolution). The study is showing the evaluation of the model simulations with satellite and ground based measurement data of SO2. The analysis is conducted on a data management platform, which is currently developed in the frame of the ESA-funded project TAMP "Technology and Atmospheric Mission Platform": it provides comprehensive functionalities to visualize and numerically compare data from different sources (model, satellite and ground-measurements).

  9. Comment on “On the quantum theory of molecules” [J. Chem. Phys. 137, 22A544 (2012)

    Energy Technology Data Exchange (ETDEWEB)

    Sutcliffe, Brian T., E-mail: bsutclif@ulb.ac.be [Service de Chimie quantique et Photophysique, Université Libre de Bruxelles, B-1050 Bruxelles (Belgium); Woolley, R. Guy [School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS (United Kingdom)

    2014-01-21

    In our previous paper [B. T. Sutcliffe and R. G. Woolley, J. Chem. Phys. 137, 22A544 (2012)] we argued that the Born-Oppenheimer approximation could not be based on an exact transformation of the molecular Schrödinger equation. In this Comment we suggest that the fundamental reason for the approximate nature of the Born-Oppenheimer model is the lack of a complete set of functions for the electronic space, and the need to describe the continuous spectrum using spectral projection.

  10. Evaluation of Meso-NH and WRF/CHEM simulated gas and aerosol chemistry over Europe based on hourly observations

    OpenAIRE

    Berger, A; Barbet, C.; M. Leriche; L. Deguillaume; Mari, C; N. Chaumerliac; Bègue, N; P. Tulet; Gazen, D.; Escobar, J

    2016-01-01

    Gas and aerosol chemistry of 10 km -resolution mesoscale models Meso-NH and WRF/CHEM were evaluated on three cases over Europe. These one-day duration cases were selected from Freney et al. (2011) and occurred on contrasted meteorological conditions and at different seasons: a cyclonic circulation with a well-marked frontal zone on winter, an anti-cyclonic situation with local storm precipitations on summer and a cold front in the northwest of Europe associated to a convergence of air masses ...

  11. Chem-Prep PZT 95/5 for neutron generator applications : development of laboratory-scale powder processing operations.

    Energy Technology Data Exchange (ETDEWEB)

    Montoya, Ted V.; Moore, Roger Howard; Spindle, Thomas Lewis Jr.

    2003-12-01

    Chemical synthesis methods are being developed as a future source of PZT 95/5 powder for neutron generator voltage bar applications. Laboratory-scale powder processes were established to produce PZT billets from these powders. The interactions between calcining temperature, sintering temperature, and pore former content were studied to identify the conditions necessary to produce PZT billets of the desired density and grain size. Several binder systems and pressing aids were evaluated for producing uniform sintered billets with low open porosity. The development of these processes supported the powder synthesis efforts and enabled comparisons between different chem-prep routes.

  12. Simulation of atmospheric N[subscript 2]O with GEOS-Chem and its adjoint: evaluation of observational constraints

    OpenAIRE

    K. C. Wells; Millet, D. B.; Bousserez, N.; D. K. Henze; Chaliyakunnel, S.; T. J. Griffis; Luan, Y.; Dlugokencky, E. J.; O'Doherty, S.; R. F. Weiss; G. S. Dutton; Elkins, J. W.; Krummel, P. B.; R. L. Langenfelds; Steele, L.P.

    2015-01-01

    We describe a new 4D-Var inversion framework for nitrous oxide (N[subscript 2]O) based on the GEOS-Chem chemical transport model and its adjoint, and apply it in a series of observing system simulation experiments to assess how well N[subscript 2]O sources and sinks can be constrained by the current global observing network. The employed measurement ensemble includes approximately weekly and quasi-continuous N[subscript 2]O measurements (hourly averages used) from several long-term monitoring...

  13. Comment on ``Free energy simulations of single and double ion occupancy in gramicidin A'' [J. Chem. Phys. 126, 105103 (2007)

    Science.gov (United States)

    Roux, Benoît; Andersen, Olaf S.; Allen, Toby W.

    2008-06-01

    In a recent article published by Bastug and Kuyucak [J. Chem. Phys.126, 105103 (2007)] investigated the microscopic factors affecting double ion occupancy in the gramicidin channel. The analysis relied largely on the one-dimensional potential of mean force of ions along the axis of the channel (the so-called free energy profile of the ion along the channel axis), as well as on the calculation of the equilibrium association constant of the ions in the channel binding sites. It is the purpose of this communication to clarify this issue.

  14. ChemCam activities and discoveries during the nominal mission of the Mars Science Laboratory in Gale crater, Mars

    Science.gov (United States)

    Maurice, Sylvestre; Clegg, Samuel M.; Wiens, Roger C.; Gasnault, O.; Rapin, W.; Forni, O.; Cousin, Agnes; Sautter, V.; Mangold, Nicolas; Le Deit, L.; Nachon, Marion; Anderson, Ryan; Lanza, Nina; Fabre, Cecile; Payre, Valerie; Lasue, Jeremie; Meslin, Pierre-Yves; LeVeille, Richard A.; Barraclough, Bruce; Beck, Pierre; Bender, Steven C.; Berger, Gilles; Bridges, John C.; Bridges, Nathan; Dromert, Gilles; Dyar, M. Darby; Francis, Raymond; Frydenvang, Jens; Gondet, B.; Ehlmann, Bethany L.; Herkenhoff, Kenneth E.; Johnson, Jeffrey R.; Langevin, Yves; Madsen Morten B.; Melikechi, N.; Lacour, J.-L.; Le Mouelic, Stephane; Lewin, Eric; Newsom, Horton E.; Ollila, Ann M.; Pinet, Patrick; Schroder, S.; Sirven, Jean-Baptiste; Tokar, Robert L.; Toplis, M.J.; d'Uston, Claude; Vaniman, David; Vasavada, Ashwin R.

    2016-01-01

    At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day). Up to Sol 800, more than 188000 LIBS spectra were acquired on more than 5800 points distributed over about 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during that period, together with a focus on the lessons learned from the first use of LIBS in space. For data processing, we describe new tools that had to be developed to account for the uniqueness of Mars data. With regard to chemistry, we present a summary of the composition range measured on Mars for major-element oxides (SiO2, TiO2, Al2O3, FeOT, MgO, CaO, Na2O, K2O) based on various multivariate models, with associated precisions. ChemCam also observed H, and the non-metallic elements C, O, P, and S, which are usually difficult to quantify with LIBS. F and Cl are observed through their molecular lines. We discuss the most relevant LIBS lines for detection of minor and trace elements (Li, Rb, Sr, Ba, Cr, Mn, Ni, and Zn). These results were obtained thanks to comprehensive ground reference datasets, which are set to mimic the expected mineralogy and chemistry on Mars. With regard to the first use of LIBS in space, we analyze and quantify, often for the first time, each of the advantages of using stand-off LIBS in space: no sample preparation, analysis within its petrological context, dust removal, sub-millimeter scale investigation, multi-point analysis, the ability to carry out statistical surveys and whole-rock analyses, and rapid data acquisition. We conclude with a discussion of ChemCam performance to survey the geochemistry of Mars, and its valuable support of decisions about selecting where and whether to make observations with more time and resource-intensive tools in the rover's instrument suite. In the end, we present a bird's-eye view of the many scientific results: discovery of felsic

  15. Response to 'Comment on 'Excitations in photoactive molecules from quantum Monte Carlo'' [J. Chem. Phys. 122, 087101 (2005)

    International Nuclear Information System (INIS)

    We find that regions of the excited state potential energy surface of formaldimine, which are accessible from the Franck-Condon configuration, are incorrectly described by the restricted open-shell Kohn-Sham (ROKS) approach. In these regions, the deviations of the ROKS energies from the time-dependent density functional theory results are not a simple shift. Contrary to what is argued in the Comment by Doltsinis and Fink [J. Chem. Phys.122, 087101 (2005)], these differences can play a role in the excited state molecular dynamics of formaldimine at finite temperature

  16. Anthropogenic contribution to cloud condensation nuclei and the first aerosol indirect climate effect modelled by GEOS-Chem/APM

    Science.gov (United States)

    Yu, F.

    2013-05-01

    Atmospheric particles influence climate indirectly by acting as cloud condensation nuclei (CCN) that affect cloud properties (albedo, lifetime, etc.) and precipitation. The first aerosol indirect radiative forcing (FAIRF) (i.e., cloud albedo effect) constitutes the largest uncertainty among the various radiative forcings quantified by the latest IPCC assessment report (IPCC2007). In order to confidently interpret climate change over the past century and project future change, it is essential to reduce the FAIRF uncertainty. One of the large sources of the uncertainty is the poor knowledge of the number concentrations and spatial distributions of pre-industrial and present-day aerosols. All previous and recent FAIRF studies are based on global models with simplified chemistry and aerosol microphysics, which may lead to large uncertainties in predicted aerosol properties and FAIRF values. Here, we investigate the anthropogenic contribution to CCN and associated FAIRF using a state-of-the-art global chemical transport and aerosol model (GEOS-Chem/APM) that contains a number of advanced features (including size-resolved sectional particle microphysics, online comprehensive SOx-NOx-Ox-VOCs chemistry, consideration of nitrate and secondary organic aerosols, online aerosol-cloud-radiation calculation, usage of more accurate assimilated meteorology, etc.). As far as we know, this is the first time that a global model with full chemistry and size-resolved (sectional) particle microphysics is employed to study FAIRF. Key aerosol properties predicted by GEOS-Chem/APM for the present-day case have been evaluated against a large set of land-, ship-, aircraft-, and satellite- based aerosol measurements including total particle number concentrations, CCN concentrations, AODs, and vertical profiles of extinction coefficients. The GEOS-Chem/APM model, with its advanced features and ability to reproduce observed aerosol properties (including CCN) around the globe, is expected to

  17. WRF-Chem Simulations of Lightning-NOx Production and Transport in Oklahoma and Colorado Thunderstorms Observed During DC3

    Science.gov (United States)

    Cummings, Kristin A.; Pickering, Kenneth E.; Barth, M.; Bela, M.; Li, Y.; Allen, D.; Bruning, E.; MacGorman, D.; Rutledge, S.; Basarab, B.; Fuchs, B.; Pollack, I.; Ryerson, T.; Carey, L.; Flocke, F.; Campos, T.; Weinheimer, A.; Diskin, G.

    2016-01-01

    The focus of this analysis is on lightning-generated nitrogen oxides (LNOx) and their distribution for two thunderstorms observed during the Deep Convective Clouds and Chemistry (DC3) field campaign in May-June 2012. The Weather Research and Forecasting Chemistry (WRF-Chem) model is used to perform cloud-resolved simulations for the May 29-30 Oklahoma severe convection, which contained one supercell, and the June 6-7 Colorado squall line. Aircraft and ground-based observations (e.g., trace gases, lightning and radar) collected during DC3 are used in comparisons against the model-simulated lightning flashes generated by the flash rate parameterization schemes (FRPSs) incorporated into the model, as well as the model-simulated LNOx predicted in the anvil outflow. Newly generated FRPSs based on DC3 radar observations and Lightning Mapping Array data are implemented in the model, along with previously developed schemes from the literature. The results of these analyses will also be compared between storms to investigate which FRPSs were most appropriate for the two types of convection and to examine the variation in the LNOx production. The simulated LNOx results from WRF-Chem will also be compared against other previously studied mid-latitude thunderstorms.

  18. Reduction and scientific analysis of data from the charge-energy-mass (CHEM) spectrometer on the AMPTE/CCE spacecraft

    Science.gov (United States)

    Gloeckler, G.; Hamilton, D. C.; Ipavich, F. M.

    1987-01-01

    The Charge-Energy-Mass (CHEM) spectrometer instrument on the AMPTE/Charge Composition Explorer (CCE) spacecraft is designed to measure the mass and charge-state abundance of magnetospheric and magnetosheath ions between 0.3 and 315 keV/e, an energy range that includes the bulk of the ring current and the dynamically important portion of the plasma sheet population. Continuing research is being conducted using the AMPTE mission data set, and in particular, that of the CHEM spectrometer which has operated flawlessly since launch and still provides excellent quality data. The requirted routine data processing and reduction, and software develpment continues to be performed. Scientific analysis of composition data in a number of magnetospheric regions including the ring current region, near-earth plasma sheet and subsolar magnetosheath continues to be undertaken. Correlative studies using data from the sister instrument SULEICA, which determines the mass and charge states of ions in the energy range of approximately 10 to 250 keV/e on the IRM, as well as other data from the CCE and IRM spacecraft, particularly in the upstream region and plasma sheet have also been undertaken.

  19. A UniChem and electron momentum spectroscopy investigations into the valence electronic structure of trans 1,3 butadiene

    International Nuclear Information System (INIS)

    The experimental (e,2e) coincidence spectroscopy, known as electron momentum spectroscopy (EMS) was applied to the trans 1,3 butadiene (C4H6) molecule with detailed binding energy spectra and orbital momentum distributions (MDs) being measured. A small selection of this data is presented. The usage of UniChem computational chemistry codes for the Flinders-developed AMOLD program allows to calculate theoretical MDs for each orbital, to help elucidate the valence electronic structure of butadiene. The results of the many-body Green's function calculation is also presented, to the ADC(3) level, for the binding energies and spectroscopic factors of the respective orbitals of C4H6. A critical comparison between the experimental and theoretical MDs allows to determine the optimum wavefunction from the basis sets studied. The determination of the wavefunction then allows to make further use of the UniChem package to derive butadiene's chemically interesting molecular properties. A summary of these results and comparison of them with the previous results of other workers is presented. 23 refs., 2 tabs., 2 figs

  20. Theoretical modeling and analysis of the emission spectra of a ChemCam standard: Basalt BIR-1A

    International Nuclear Information System (INIS)

    We report on efforts to perform theoretical modeling of the emission spectrum measured from a basalt sample. We compare our calculations with measurements that were made to provide standards for the ChemCam instrument on the Mars Science Laboratory. We find that to obtain good agreement between modeling and the measurement, it is necessary to determine atomic and ionic level populations via a multi-element approach in which the free electron density that is created influences all the species within the plasma. Calculations that consider each element separately are found to be in poorer agreement with the measured spectrum, indicating that the ‘matrix effect’ term often used to describe the influence of other species on the emission spectrum from a given element is due to the influence of the global electron density of the plasma. We explore the emission features in both the visible and near-infrared wavelength ranges, and also examine radiation transport effects for some of the most intense features found in the basalt spectrum. Finally, we also provide comparisons of the ChemCam measurement with new high-resolution spectral measurements. - Highlights: • LIBS basalt spectrum • Ab-initio theoretical modeling • Discussion of matrix effects • Discussion of radiation transport effects • High-resolution measurements of Basalt

  1. Investigating marine stratocumulus with a fully coupled cloud-aerosol scheme in a WRF/Chem Large Eddy Simulation

    Science.gov (United States)

    Kazil, J.; Wang, H.; Feingold, G.

    2009-12-01

    Drizzle in stratocumulus clouds is triggered by low concentrations of cloud condensation nuclei (CCN), and concurrently acts as a sink of CCN. The progression of this cloud-aerosol feedback may result in a transition in marine boundary layer dynamics and cloud structure; Closed cell circulation, characterized by a solid stratocumulus layer, may transition into an open cellular mode featuring low cloud fraction. Aerosol sources may balance the loss of CCN from drizzle, and delay or prevent the emergence of open cell circulation. Such sources include particle emissions from the sea surface, entrainment of aerosol from the free troposphere into the cloud deck, advection from land sources, and aerosol nucleation. In order to investigate the role of aerosol sources and processes in the transition between these two states, we have coupled in detail aerosol processes, cloud microphysics, and gas and aqueous chemistry in the WRF/Chem model. We operate WRF/Chem in Large Eddy Simulation mode. Aerosol nucleation is described with a sulfuric acid/water scheme based on laboratory measurements of the nucleation process. Here we present first results on the role of aerosol nucleation for cloud properties and drizzle formation in pristine conditions of the South-East Pacific region, and in polluted conditions.

  2. The potassic sedimentary rocks in Gale Crater, Mars, as seen by ChemCam on board Curiosity

    Science.gov (United States)

    Le Deit, L.; Mangold, N.; Forni, O.; Cousin, A.; Lasue, J.; Schröder, S.; Wiens, R. C.; Sumner, D.; Fabre, C.; Stack, K. M.; Anderson, R. B.; Blaney, D.; Clegg, S.; Dromart, G.; Fisk, M.; Gasnault, O.; Grotzinger, J. P.; Gupta, S.; Lanza, N.; Le Mouélic, S.; Maurice, S.; McLennan, S. M.; Meslin, P.-Y.; Nachon, M.; Newsom, H.; Payré, V.; Rapin, W.; Rice, M.; Sautter, V.; Treiman, A. H.

    2016-05-01

    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system. From ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than 5 times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e., mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater, are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  3. Theoretical modeling and analysis of the emission spectra of a ChemCam standard: Basalt BIR-1A

    Energy Technology Data Exchange (ETDEWEB)

    Colgan, J. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Judge, E.J. [Chemical Diagnostics and Engineering, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Johns, H.M.; Kilcrease, D.P. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Barefield, J.E. [Chemical Diagnostics and Engineering, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); McInroy, R. [Physical Chemistry and Applied Spectroscopy, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hakel, P. [Computational Physics Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Wiens, R.C. [Space and Remote Sensing Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Clegg, S.M. [Physical Chemistry and Applied Spectroscopy, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2015-08-01

    We report on efforts to perform theoretical modeling of the emission spectrum measured from a basalt sample. We compare our calculations with measurements that were made to provide standards for the ChemCam instrument on the Mars Science Laboratory. We find that to obtain good agreement between modeling and the measurement, it is necessary to determine atomic and ionic level populations via a multi-element approach in which the free electron density that is created influences all the species within the plasma. Calculations that consider each element separately are found to be in poorer agreement with the measured spectrum, indicating that the ‘matrix effect’ term often used to describe the influence of other species on the emission spectrum from a given element is due to the influence of the global electron density of the plasma. We explore the emission features in both the visible and near-infrared wavelength ranges, and also examine radiation transport effects for some of the most intense features found in the basalt spectrum. Finally, we also provide comparisons of the ChemCam measurement with new high-resolution spectral measurements. - Highlights: • LIBS basalt spectrum • Ab-initio theoretical modeling • Discussion of matrix effects • Discussion of radiation transport effects • High-resolution measurements of Basalt.

  4. Interaction of host-guest complexes of cucurbit[n]urils with double probe guests

    Institute of Scientific and Technical Information of China (English)

    MA; Peihua; DONG; Jun; XIANG; Shuangchun; XUE; Saifeng; ZH

    2004-01-01

    [1]Freeman, W. A., Mock, W. L., Shih, N. Y., Cucurbituril, J. Am.Chem. Soc., 1981, 103: 7367-7368.[2]Day, A. I., Arnold, A. P., Method for synthesis cucurbiturils, WO 0068232, 2000, 8.[3]Kim, J., Jung, I. S., Kim, S. Y. et al., New cucurbituril homologues: syntheses, isolation, characterization, and X-ray crystal structures of cucurbit[n]uril (n = 5, 7 and 8), J. Am. Chem. Soc.,2000, 122(3): 540-541.[4]Day, A. I., Blanck, R. J, Amold, A. P., A cucurbituril-based gyroscane: a new supramolecular form, Angew. Chem. Int. Ed., 2002,41(2): 275-277.[5]Blanck, R. J., Sleeman, A. J. White, T. J. et al., Cucurbit[7]uril and o-carborane self-assemble to form a molecular ball bearing,Nano. Lett., 2002, 2(2), 147-149.[6]Liu, J. X., Tao, Z., Xue, S. F. et al., Investigation of host-guest compounds of cucurbit[n = 5-8]uril with some piperazine derivatives, Chin. J. Inorg. Chem., 2004, 20(2): 139-147[7]Zhou, Y. L., Liu, Y., Inclusion complex of β-cyclodextrin and α-aminopyridine and its assembling behavior, Science in China,Ser. B, 2004, 34(1): 68-74.[8]Ong, W., Kaifer, A. E., Molecular encapsulation by cucurbit[7]uril of the apical 4,4'-bipyridinium residuein newkome-type dendrime,Angew. Chem. Inter. Ed., 2003, 42: 2164-2167.[9]Samsonenko, D. G., Gerasko, O. A., Mitkina, T. V. et al., Synthesis and crystal structure of supramolecular adducts of macrocyclic cavitand cucurbituril with chromium (Ⅲ) and nickel (Ⅱ) aqua complexes, Russian J. Coord. Chem. (Translation of Koordinatsionnaya Khimiya), 2003, 29(3): 166-174.[10]He, X. Y., Li, G., Chen, H. L., A new cucurbituril-based metallo-rotaxane, Inorg. Chem. Commun., 2002, (5): 633-641.[11]Fedin, V. P., Sokolov, M. N., Dybtsev, D. N. et al., Supramolecular assemblies of [Mo3Se4Clx(H2O)9-x](4-x)+ with cucurbituril;complementarity control through the variation of x, Inorg. Chim.Acta., 2002, 331(1): 31-38.[12]Lorenzo, S., Day, A., Craig, D. et al., The first endoannular metal halide

  5. Overview of 3 years of ChemCam' chemical compositions along the Curiosity's traverse at Gale Crater.

    Science.gov (United States)

    Cousin, Agnès; Wiens, Roger; Maurice, Sylvestre; Gasnault, Olivier

    2016-04-01

    Curiosity rover has been in Gale crater for more than3 years now. It drove ~12 km from its landing point up to the Bagnold Dunes. The ChemCam instrument is widely used to assess the chemistry of rocks and soils at the submillimeter scale. As of sol 1200, ChemCam sampled >1000 targets, corresponding to >300000 laser shots, >6000 images, and many passive spectra. The Bradbury landing site, a plain located at a distal portion of the alluvial fan from Peace Vallis, exposed several float rocks presenting igneous compositions ranging from mafic up to a trachytic end-member. These observations provided an important clue concerning the diversity of early Mars magmatism that was not previously recognized. More igneous float rocks have been observed all along the traverse, being more felsic closer to the landing site, and more mafic near the cratered unit, after the Kimberley formation. The Sheepbed area is essentially composed of mudstones that show a very homogeneous composition, close to the average Martian crust, providing evidence of aqueous episodes with little alteration in this area. ChemCam showed that the bedrock host experienced other diagenetic events with Mg- and Fe-rich clays in erosion-resistant raised ridges on one hand, and calcium sulfate veins on the other hand. The nearby Shaler fluvial sandstone outcrop, the first outcrop of potential deltaic foreset beds, shows K enrichment. This enrichment is also observed at the Kimberley formation (another drill site flanked by foreset beds), located 7 km SW of Shaler, with up to 5.3 wt % at the Mount Remarkable member. Conglomerates have been analyzed in detail all along the traverse as they represent a link between the source rocks and the finer-grained sediments such as the sandstones and mudstones. They have shown an average composition that is enriched in alkalis, Al, and Si compared to the average Martian crust, with a clear enrichment in K2O in the vicinity of the Kimberley formation. Enrichment in K2O at

  6. Investigación sobre la adaptación de robots para funciones de intérprete

    OpenAIRE

    Suárez Martínez, Daniel

    2015-01-01

    Este proyecto consiste en la investigación y estudio del estado del arte de la robótica así como el diseño y desarrollo de diferentes aplicaciones que dotan a un robot de funciones que le permiten ejercer de intérprete de distintas maneras, además de que estas funciones puedan tener efecto de forma remota, lo cual aborda la utilización de ingeniería web en este proyecto. En el presente documento se explica en qué es, en qué consiste y cómo se utiliza el Robot Operating System (ROS), qué re...

  7. Intérêt du dosage de la procalcitonine chez le sujet âgé

    OpenAIRE

    Stucker, Fabien; Hermann, François; Krause, Karl-Heinz

    2007-01-01

    La procalcitonine a été étudiée à de nombreuses reprises chez l'adulte jeune présentant des infections bactérienne comme marqueur spécifique et précoce de l'inflammation, ainsi que comme prédicteur de la sévérité de l'atteinte. L'intérêt de son dosage chez la personne âgée n'a jamais été démontré. Une étude observationnelle a donc été conduite chez 218 patients âgés, non sélectionnés, admis en secteur hospitalier et les sensibilités (24%) et spécificité (94%) de la procalcitonine comme prédic...

  8. Intérêt du dosage de la procalcitonine chez le sujet âgé

    OpenAIRE

    Stucker, Fabien

    2006-01-01

    La procalcitonine a été étudiée à de nombreuses reprises chez l'adulte jeune présentant des infections bactérienne comme marqueur spécifique et précoce de l'inflammation, ainsi que comme prédicteur de la sévérité de l'atteinte. L'intérêt de son dosage chez la personne âgée n'a jamais été démontré. Une étude observationnelle a donc été conduite chez 218 patients âgés, non sélectionnés, admis en secteur hospitalier et les sensibilités (24%) et spécificité (94%) de la procalcitonine comme prédic...

  9. ISIDORE, de l'interconnexion de données à l'intégration de services

    OpenAIRE

    Maignien, Yannick

    2011-01-01

    L'inauguration officielle par le CNRS de la plateforme SHS ISIDORE, déjà en ligne en version beta depuis décembre 2010, est l'occasion de rappeler quelques caractéristiques de cette réalisation, en matière de méthodologie de projet, mais surtout de souligner l'ambition de cette infrastructure en matière de connexion de données exprimées en RDF et les perspectives de développement en matière d'intégration de services que l'on peut attendre du Web de données pour les sciences.

  10. Modélisation Intégrée du Changement Climatique - Contribution de l'optimisation par Oracle

    OpenAIRE

    Drouet, Laurent

    2006-01-01

    La modélisation intégrée du changement climatique a été introduite il y a une vingtaine d’années pour faire le lien entre les sciences humaines, les sciences de la vie et celles du climat afin de répondre aux questions des décideurs sur le problème du changement climatique. Cette thèse présente la méthode de couplage des dynamiques du climat et de l’économie et reformule de cette façon les problèmes d’optimisation de politiques climatiques. À partir de la méthode d’optimisation par oracle et l...

  11. Bien commun, conflits d’intérêts et délibération éthique

    OpenAIRE

    Müller, Denis

    2016-01-01

    Si la notion de bien commun paraît de prime abord trop ambitieuse, trompeuse en ses promesses excessives et inaccessibles, elle est néanmoins nécessaire au débat éthique dans l’espace public contemporain. Cette contribution veut montrer comment une compréhension critique de la notion controversée de bien commun peut s’avérer compatible avec une prise en compte réaliste et responsable des conflits d’intérêts et de la délibération éthique. L’exemple du débat français sur la laïcité permet à cet...

  12. L’obligation d’accommodement : un outil juridique et une mesure d’intégration

    OpenAIRE

    Jézéquel, Myriam

    2015-01-01

    Dans sa lutte contre les discriminations, le Canada s’est doté de mécanismes juridiques pour prévenir ou résoudre les conflits entre normes religieuses et normes civiles. L’obligation d’accommodement raisonnable est l’un de ces mécanismes qui visent à prendre des mesures raisonnables pour respecter les besoins spécifiques qui différencient certaines personnes de la majorité, et ce, afin de protéger leur droit à l’égalité. Il répond donc à un objectif d’intégration des minorités. Toutefois, ac...

  13. Le meilleur intérêt de l’enfant dont la garde est contestée : enjeux, contexte et pratiques

    OpenAIRE

    Godbout, Élisabeth; Parent, Claudine; Saint-Jacques, Marie-Christine

    2016-01-01

    Cette recension des écrits théoriques, scientifiques et professionnels s’intéresse à trois questions en lien avec la détermination du meilleur intérêt de l’enfant dont la garde est contestée à la suite d’une séparation : 1) Quels sont les enjeux entourant le principe de meilleur intérêt de l’enfant ? 2) Quelles sont les caractéristiques des situations qui se retrouvent à être expertisées ou débattues en cour ? 3) Comment ce principe est-il évalué concrètement ; quel poids est accordé à différ...

  14. Interações entre o aluno com surdez, o professor e o intérprete em aulas de física: uma perspectiva Vygotskiana

    Directory of Open Access Journals (Sweden)

    Jaqueline Santos Vargas

    2014-09-01

    Full Text Available O estudo apresenta uma análise das interações entre o aluno com surdez, o professor e o intérprete em sala de aula, além do papel desses sujeitos no processo de inclusão do aluno surdo. Trata-se de uma pesquisa qualitativa realizada em 10 escolas públicas de Ensino Médio de Campo Grande-MS que receberam 24 alunos com surdez. Nessa análise utilizamos a abordagem histórico cultural de Vygotsky. Os resultados evidenciaram que apenas o intérprete interage efetivamente com esses alunos e pouco colabora para que eles interajam com pessoas que não dominam a Língua Brasileira de Sinais. Em sala de aula, o professor transfere ao intérprete a responsabilidade pelo ensino e a aprendizagem desses alunos.

  15. Vibrational evidence for chiral recognition phenomena in vacuo

    Science.gov (United States)

    Suhm, Martin A.

    2007-06-01

    'eh'eret, F. Lahmani, A. Zehnacker, Chem. Phys. Lett. 1995, 237, 480 [2] J.P.I. Hearn, R.V. Cobley, B.J. Howard, J. Chem. Phys., 2005, 123, 134324; Z. Su, N. Borho, Y. Xu, J. Am. Chem. Soc. 2006, 128, 17126 [3] K. Le Barbu, F. Lahmani, A. Zehnacker, J. Phys. Chem. A, 2002, 106, 6271 [4] N. Borho and M. A. Suhm, Phys. Chem. Chem. Phys., 2002, 4, 2721 [5] N. Borho and M. A. Suhm, Org. Biomol. Chem., 2003, 1, 4351 [6] T. Scharge, T. H"aber, M. A. Suhm, Phys. Chem. Chem. Phys., 2006, 8, 4664 [7] N. Borho, M. A. Suhm, K. Le Barbu-Debus, A. Zehnacker, Phys. Chem. Chem. Phys., 2006, 8, 4449 [8] T. B. Adler, N. Borho, M. Reiher, M. A. Suhm, Angew. Chem. Int. Ed., 2006, 45, 3440

  16. Evaluation of the high resolution WRF-Chem (v3.4.1) air quality forecast and its comparison with statistical ozone predictions

    Science.gov (United States)

    Žabkar, R.; Honzak, L.; Skok, G.; Forkel, R.; Rakovec, J.; Ceglar, A.; Žagar, N.

    2015-07-01

    An integrated modelling system based on the regional online coupled meteorology-atmospheric chemistry WRF-Chem model configured with two nested domains with horizontal resolutions of 11.1 and 3.7 km has been applied for numerical weather prediction and for air quality forecasts in Slovenia. In the study, an evaluation of the air quality forecasting system has been performed for summer 2013. In the case of ozone (O3) daily maxima, the first- and second-day model predictions have been also compared to the operational statistical O3 forecast and to the persistence. Results of discrete and categorical evaluations show that the WRF-Chem-based forecasting system is able to produce reliable forecasts which, depending on monitoring site and the evaluation measure applied, can outperform the statistical model. For example, the correlation coefficient shows the highest skill for WRF-Chem model O3 predictions, confirming the significance of the non-linear processes taken into account in an online coupled Eulerian model. For some stations and areas biases were relatively high due to highly complex terrain and unresolved local meteorological and emission dynamics, which contributed to somewhat lower WRF-Chem skill obtained in categorical model evaluations. Applying a bias correction could further improve WRF-Chem model forecasting skill in these cases.

  17. Vård som inte kan anstå : Tolkning i relation till den etiska plattformen och nationella modellen för öppna prioriteringar

    OpenAIRE

    Sandman, Lars; Broqvist, Mari; Gustavsson, Erik; Arvidsson, Eva; Ekerstad, Niklas; Carlsson, Per

    2014-01-01

    Metod Uppdraget från Socialstyrelsen består av tre sammanhängande delar. I den första delen presenteras olika tolkningar av begreppet vård som inte kan anstå utifrån en analys av hur begreppet används i den aktuella propositionen och lagtexten. Dessa tolkningar specificeras i ett antal kriterier. I den andra delen analyseras dessa tolkningar utifrån den etiska plattformen. Den tredje delen syftar till att analysera hur begreppet vård som inte kan anstå förhåller sig till den nationella modell...

  18. ChemSkill Builder 2000, Version 6.1 [CD-ROM] (by James D. Spain and Harold J. Peters)

    Science.gov (United States)

    Keeney-Kennicutt, Reviewed By Wendy L.

    2000-07-01

    One of the major challenges for faculty teaching general chemistry is how to encourage students to practice solving problems. We know that for students to develop chemical intuition and problem-solving skills, they must "get their hands dirty" as they decipher and unravel problems inherent to our discipline. One tool that I've used since its release in 1996 is the ChemSkill Builder, an electronic homework package. The latest version, ChemSkill Builder (CSB) 2000, version 6.1, is an excellent, effective integration of teaching and testing most quantitative and conceptual learning objectives in an interactive way. It is inexpensive and easy to use for both students and faculty. The CSB 2000 package of personalized problem sets, specifically designed to complement most general chemistry courses, is a program on CD-ROM for PC Windows users (3.1, 95, or 98), with more than 1500 questions and a 3 1/2-in. record-management disk. There is a separate grade-management disk for the instructor. It has 24 gradable chapters, each with 5 or 6 sections, plus two new chapters that are not graded: Polymer Chemistry and an Appendix of Chemical Skills. Each section begins with a short review of the topic and many have interactive explanations. If students miss an answer, they are given a second chance for 70% credit. If they still miss, the worked-out solution is presented in detail. Students can work each section as many times as they wish to improve their scores. Periodically, the students download their data directly into a PC set up by the instructor. The data can be easily converted into an ASCII file and merged with a spreadsheet. The use of CD-ROM solves the sporadic problems associated with previous versions on 3 1/2-in. disks: software glitches, failed disks, and system incompatibilities. The quality and number of graphics and interactive exercises are much improved in this latest version. I particularly enjoyed the interactive explanations of significant figures and

  19. Multiconfigurational quantum chemistry for actinide containing systems: from isolated molecules to condensed phase

    International Nuclear Information System (INIS)

    Complete text of publication follows: Ab initio quantum chemistry is a mature science that allows the study of molecular species containing any of the atoms in the periodic system. In this lecture I will describe our latest achievements in the prediction of novel chemical bonds and chemical species, including the multiple bond in the early-di-actinide series [1] and some novel inorganic compounds containing the di-uranium moiety [2]. In nature most of actinide chemistry occurs in solution. We try to combine ab initio quantum chemistry with classical molecular dynamics simulations in order to understand the behavior of highly charged ions in solution. Our recent studies of uranyl [3] and Cm(III) [4] in water will be presented. References: [1] B. O. Roos, P.-A. Malmqvist and L. Gagliardi, Exploring the actinide-actinide bond: Theoretical studies of the chemical bond in Ac2, Th2, Pa2, and U2 J. Am. Chem. Soc. 128, 17000-17006 (2006) [2] G. La Macchia, M. Brynda, and L. Gagliardi, Quantum chemical calculations predict the diphenyl di-uranium compound, PhUUPh, to have a stable 1Ag ground state Angew. Chem. Int. Ed. 45, 6210-6213 (2006); [3] D. Hagberg, G. Karlstrom, B .O. Roos and L. Gagliardi, The coordination of uranyl in water: a combined quantum chemical and molecular simulation study J. Am. Chem. Soc. 127, 14250-14256 (2005); [4] E. Bednarz, D. Hagberg, L. Gagliardi in preparation

  20. Interactions between volatile organic compounds and reactive halogen in the tropical marine atmosphere using WRF-Chem

    Science.gov (United States)

    Badia, Alba; Reeves, Claire E.; Baker, Alex; Volkamer, Rainer; von Glasow, Roland

    2016-04-01

    Halogen species (chlorine, bromine and iodine) are known to play an important role in the chemistry and oxidizing capacity of the troposphere, particularly in the marine boundary layer (MBL). Reactive halogens cause ozone (O3) destruction, change the HOx and NOX partitioning, affect the oxidation of volatile organic compounds (VOCs) and mercury, reduce the lifetime of methane, and take part in new particle formation. Numerical models predicted that reactive halogen compounds account for 30% of O3 destruction in the MBL and 5-20% globally. There are indications that the chemistry of reactive halogens and oxygenated VOCs (OVOCs) in the tropics are inter-related. Moreover, the presence of aldehydes, such as glyoxal (CHOCHO), has a potential impact on radical cycling and secondary organic aerosol (SOA) formation in the MBL and free troposphere (FT). Model calculations suggest aldehydes to be an important sink for bromine atoms and hence competition for their reaction with O3 forming BrO and so illustrating a link between the cycles of halogens and OVOCs in the marine atmosphere. The main objective of this contribution is to investigate the atmospheric chemistry in the tropical East Pacific with a focus on reactive halogens and OVOCs and their links using the latest version of the Weather Research and Forecasting (WRF) model coupled with Chemistry (WRF-Chem) and field data from the TORERO campaign. WRF-Chem is a highly flexible community model for atmospheric research where aerosol-radiation-cloud feedback processes are taken into account. Our current reaction mechanism in WRF-Chem is based on the MOZART mechanism and has been extended to include bromine, chlorine and iodine chemistry. The MOZART mechanism includes detailed gas-phase chemistry of CHOCHO formation as well as state-of-the-science pathways to form SOA. Oceanic emissions of aldehydes, including CHOCHO, and of organic halogens based on measurements from the TORERO campaign have been added into the model. Sea

  1. Top-Down Inversion of Aerosol Emissions through Adjoint Integration of Satellite Radiance and GEOS-Chem Chemical Transport Model

    Science.gov (United States)

    Xu, X.; Wang, J.; Henze, D. K.; Qu, W.; Kopacz, M.

    2012-12-01

    The knowledge of aerosol emissions from both natural and anthropogenic sources are needed to study the impacts of tropospheric aerosol on atmospheric composition, climate, and human health, but large uncertainties persist in quantifying the aerosol sources with the current bottom-up methods. This study presents a new top-down approach that spatially constrains the amount of aerosol emissions from satellite (MODIS) observed reflectance with the adjoint of a chemistry transport model (GEOS-Chem). We apply this technique with a one-month case study (April 2008) over the East Asia. The bottom-up estimated sulfate-nitrate-ammonium precursors, such as sulfur dioxide (SO2), ammonia (NH3), and nitrogen oxides (NOx), all from INTEX-B 2006 inventory, emissions of black carbon (BC), organic carbon (OC) from Bond-2007 inventory, and mineral dust simulated from DEAD dust mobilization scheme, are spatially optimized from the GEOS-Chem model and its adjoint constrained by the aerosol optical depth (AOD) that are derived from MODIS reflectance with the GEOS-Chem aerosol single scattering properties. The adjoint inverse modeling for the study period yields notable decreases in anthropogenic aerosol emissions over China: 436 Gg (33.5%) for SO2, 378 Gg (34.5%) for NH3, 319 (18.8%) for NOx, 10 Gg (9.1%) for BC, and 30 Gg (15.0%) for OC. The total amount of the mineral dust emission is reduced by 56.4% from the DEAD mobilization module which simulates dust production of 19020 Gg. Sub-regional adjustments are significant and directions of changes are spatially different. The model simulation with optimized aerosol emissions shows much better agreement with independent observations from sun-spectrophotometer observed AOD from AERONET, MISR (Multi-angle Imaging SpectroRadiometer) AOD, OMI (Ozone Monitoring Instrument) NO2 and SO2 columns, and surface aerosol concentrations measured over both anthropogenic pollution and dust source regions. Assuming the used bottom-up anthropogenic

  2. The ChemCam instrument suite on the Mars science laboratory (MSL) rover: Science objectives and mast unit description

    International Nuclear Information System (INIS)

    ChemCam is a remote sensing instrument suite on board the 'Curiosity' rover (NASA) that uses Laser-Induced Breakdown Spectroscopy (LIBS) to provide the elemental composition of soils and rocks at the surface of Mars from a distance of 1.3 to 7 m, and a telescopic imager to return high resolution context and micro-images at distances greater than 1.16 m. We describe five analytical capabilities: rock classification, quantitative composition, depth profiling, context imaging, and passive spectroscopy. They serve as a toolbox to address most of the science questions at Gale crater. ChemCam consists of a Mast-Unit (laser, telescope, camera, and electronics) and a Body-Unit (spectrometers, digital processing unit, and optical de-multiplexer), which are connected by an optical fiber and an electrical interface. We then report on the development, integration, and testing of the Mast-Unit, and summarize some key characteristics of ChemCam. This confirmed that nominal or better than nominal performances were achieved for critical parameters, in particular power density (≥ 1 GW/cm2). The analysis spot diameter varies from 350 μm at 2 m to 550 μm at 7 m distance. For remote imaging, the camera field of view is 20 mrad for 1024*1024 pixels. Field tests demonstrated that the resolution (∼ 90 μrad) made it possible to identify laser shots on a wide variety of images. This is sufficient for visualizing laser shot pits and textures of rocks and soils. An auto-exposure capability optimizes the dynamical range of the images. Dedicated hardware and software focus the telescope, with precision that is appropriate for the LIBS and imaging depths-of-field. The light emitted by the plasma is collected and sent to the Body-Unit via a 6 m optical fiber. The companion to this paper (Wiens et al. this issue) reports on the development of the Body-Unit, on the analysis of the emitted light, and on the good match between instrument performance and science specifications. (authors)

  3. The ChemCam Instrument Suite on the Mars Science Laboratory (MSL) Rover: Science Objectives and Mast Unit Description

    Science.gov (United States)

    Maurice, S.; Wiens, R.C.; Saccoccio, M.; Barraclough, B.; Gasnault, O.; Forni, O.; Mangold, N.; Baratoux, D.; Bender, S.; Berger, G.; Bernardin, J.; Berthé, M.; Bridges, N.; Blaney, D.; Bouyé, M.; Caïs, P.; Clark, B.; Clegg, S.; Cousin, A.; Cremers, D.; Cros, A.; DeFlores, L.; Derycke, C.; Dingler, B.; Dromart, G.; Dubois, B.; Dupieux, M.; Durand, E.; d'Uston, L.; Fabre, C.; Faure, B.; Gaboriaud, A.; Gharsa, T.; Herkenhoff, K.; Kan, E.; Kirkland, L.; Kouach, D.; Lacour, J.-L.; Langevin, Y.; Lasue, J.; Le Mouélic, S.; Lescure, M.; Lewin, E.; Limonadi, D.; Manhès, G.; Mauchien, P.; McKay, C.; Meslin, P.-Y.; Michel, Y.; Miller, E.; Newsom, Horton E.; Orttner, G.; Paillet, A.; Parès, L.; Parot, Y.; Pérez, R.; Pinet, P.; Poitrasson, F.; Quertier, B.; Sallé, B.; Sotin, C.; Sautter, V.; Séran, H.; Simmonds, J.J.; Sirven, J.-B.; Stiglich, R.; Striebig, N.; Thocaven, J.-J.; Toplis, M.J.; Vaniman, D.

    2012-01-01

    ChemCam is a remote sensing instrument suite on board the "Curiosity" rover (NASA) that uses Laser-Induced Breakdown Spectroscopy (LIBS) to provide the elemental composition of soils and rocks at the surface of Mars from a distance of 1.3 to 7 m, and a telescopic imager to return high resolution context and micro-images at distances greater than 1.16 m. We describe five analytical capabilities: rock classification, quantitative composition, depth profiling, context imaging, and passive spectroscopy. They serve as a toolbox to address most of the science questions at Gale crater. ChemCam consists of a Mast-Unit (laser, telescope, camera, and electronics) and a Body-Unit (spectrometers, digital processing unit, and optical demultiplexer), which are connected by an optical fiber and an electrical interface. We then report on the development, integration, and testing of the Mast-Unit, and summarize some key characteristics of ChemCam. This confirmed that nominal or better than nominal performances were achieved for critical parameters, in particular power density (>1 GW/cm2). The analysis spot diameter varies from 350 μm at 2 m to 550 μm at 7 m distance. For remote imaging, the camera field of view is 20 mrad for 1024×1024 pixels. Field tests demonstrated that the resolution (˜90 μrad) made it possible to identify laser shots on a wide variety of images. This is sufficient for visualizing laser shot pits and textures of rocks and soils. An auto-exposure capability optimizes the dynamical range of the images. Dedicated hardware and software focus the telescope, with precision that is appropriate for the LIBS and imaging depths-of-field. The light emitted by the plasma is collected and sent to the Body-Unit via a 6 m optical fiber. The companion to this paper (Wiens et al. this issue) reports on the development of the Body-Unit, on the analysis of the emitted light, and on the good match between instrument performance and science specifications.

  4. Comment on ''Mean force potential for the calcium--chloride ion pair in water'' [J. Chem. Phys. 99, 4229 (1993)

    International Nuclear Information System (INIS)

    The interionic potential of mean force (pmf) for the Ca++--Cl- ion pair in water is computed using the molecular dynamics computer simulation technique. The calculated pmf indicates a stable contact pair (CIP) and a solvent-separated pair (SSIP) centered at 2.9 and 5.0 A with a 2.8 kcal/mol barrier to dissociation. The SSIP well is about 2.0 kcal/mol deeper than the CIP suggesting that water molecules in the first hydration shell are strongly coordinated to the Ca++ ion. Our results do not agree with the pmf reported recently by Guardia, Robinson, Padro [J. Chem. Phys. 99, 4229 (1993)]. Possible reasons for the discrepancy are discussed

  5. Closure on the single scattering albedo in the WRF-Chem framework using data from the MILAGRO campaign

    Directory of Open Access Journals (Sweden)

    J. C. Barnard

    2009-02-01

    Full Text Available Data from the MILAGRO field campaign, which took place in the Mexico City Metropolitan Area (MCMA during March 2006, is used to perform a closure experiment between aerosol chemical properties and aerosol optical properties. Measured aerosol chemical properties, obtained from the MILAGRO T1 site, are fed to two different "chemical to optical properties" modules. One module uses a sectional approach and is identical to that used in the WRF-Chem model, while the other is based on a modal approach. This modal code is employed as an independent check on the WRF-Chem module. Both modules compute aerosol optical properties and, in particular, the single-scattering albedo, ϖ0, as a function of time. The single-scattering albedos are compared to independent measurements obtained from a photoacoustic spectrometer (PAS. Because chemical measurements of the aerosol coarse mode were not available, and the inlet of the PAS could not ingest aerosols larger than about 2 to 3 μm, we focus here on the fine-mode ϖ0. At 870 nm, the wavelength of the PAS measurements, the agreement between the computed (modal and WRF-Chem and observed fine-mode ϖ0, averaged over the course of the campaign, is reasonably good. The observed ϖ0 value is 0.77, while for both modules, the calculated value was 0.75 resulting in a difference of 0.02 between observations and both computational approaches. This difference is less than the uncertainty of the observed ϖ0 values (6%, or 0.05, and therefore "closure" is achieved, at least for mean values. After adjusting some properties of black carbon absorption and mass concentration within plausible uncertainty limits, the two modules simulate well the diurnal variation of ϖ0, and the absorption coefficient, Babs, but are less successful in calculating the variation of the scattering coefficient, Bscat. This difficulty is probably

  6. Evaluation of UTLS carbon monoxide simulations in GMI and GEOS-Chem chemical transport models using Aura MLS observations

    Science.gov (United States)

    Huang, Lei; Jiang, Jonathan H.; Murray, Lee T.; Damon, Megan R.; Su, Hui; Livesey, Nathaniel J.

    2016-05-01

    This study evaluates the distribution and variation of carbon monoxide (CO) in the upper troposphere and lower stratosphere (UTLS) during 2004-2012 as simulated by two chemical transport models, using the latest version of Aura Microwave Limb Sounder (MLS) observations. The simulated spatial distributions, temporal variations and vertical transport of CO in the UTLS region are compared with those observed by MLS. We also investigate the impact of surface emissions and deep convection on CO concentrations in the UTLS over different regions, using both model simulations and MLS observations. Global Modeling Initiative (GMI) and GEOS-Chem simulations of UTLS CO both show similar spatial distributions to observations. The global mean CO values simulated by both models agree with MLS observations at 215 and 147 hPa, but are significantly underestimated by more than 40 % at 100 hPa. In addition, the models underestimate the peak CO values by up to 70 % at 100 hPa, 60 % at 147 hPa and 40 % at 215 hPa, with GEOS-Chem generally simulating more CO at 100 hPa and less CO at 215 hPa than GMI. The seasonal distributions of CO simulated by both models are in better agreement with MLS in the Southern Hemisphere (SH) than in the Northern Hemisphere (NH), with disagreements between model and observations over enhanced CO regions such as southern Africa. The simulated vertical transport of CO shows better agreement with MLS in the tropics and the SH subtropics than the NH subtropics. We also examine regional variations in the relationships among surface CO emission, convection and UTLS CO concentrations. The two models exhibit emission-convection-CO relationships similar to those observed by MLS over the tropics and some regions with enhanced UTLS CO.

  7. Evaluation of UTLS Carbon Monoxide Simulations in GMI and GEOS-Chem Chemical Transport Models using Aura MLS Observations

    Science.gov (United States)

    Huang, Lei; Jiang, Jonathan H.; Murray, Lee T.; Damon, Megan R.; Su, Hui; Livesey, Nathaniel J.

    2016-01-01

    This study evaluates the distribution and variation of carbon monoxide (CO) in the upper troposphere and lower stratosphere (UTLS) during 2004-2012 as simulated by two chemical transport models, using the latest version of Aura Microwave Limb Sounder (MLS) observations. The simulated spatial distributions, temporal variations and vertical transport of CO in the UTLS region are compared with those observed by MLS. We also investigate the impact of surface emissions and deep convection on CO concentrations in the UTLS over different regions, using both model simulations and MLS observations. Global Modeling Initiative (GMI) and GEOS-Chem simulations of UTLS CO both show similar spatial distributions to observations. The global mean CO values simulated by both models agree with MLS observations at 215 and 147 hPa, but are significantly underestimated by more than 40% at 100 hPa. In addition, the models underestimate the peak CO values by up to 70% at 100 hPa, 60% at 147 hPa and 40% at 215 hPa, with GEOS-Chem generally simulating more CO at 100 hPa and less CO at 215 hPa than GMI. The seasonal distributions of CO simulated by both models are in better agreement with MLS in the Southern Hemisphere (SH) than in the Northern Hemisphere (NH), with disagreements between model and observations over enhanced CO regions such as southern Africa. The simulated vertical transport of CO shows better agreement with MLS in the tropics and the SH subtropics than the NH subtropics. We also examine regional variations in the relationships among surface CO emission, convection and UTLS CO concentrations. The two models exhibit emission-convection- CO relationships similar to those observed by MLS over the tropics and some regions with enhanced UTLS CO.

  8. Spatio-temporal variability of aerosols over East China inferred by merged visibility-GEOS-Chem aerosol optical depth

    Science.gov (United States)

    Lin, Jintai; Li, Jing

    2016-05-01

    Long-term visibility measurements offer useful information for aerosol and climate change studies. Recently, a new technique to converting visibility measurements to aerosol optical depth (AOD) has been developed on a station-to-station basis (Lin et al., 2014). However, factors such as human observation differences and local meteorological conditions often impair the spatial consistency of the visibility converted AOD dataset. Here we further adopt AOD spatial information from a chemical transport model GEOS-Chem, and merge visibility inferred and modeled early-afternoon AOD over East China on a 0.667° long. × 0.5° lat. grid for 2005-2012. Comparisons with MODIS/Aqua retrieved AOD and subsequent spectral decomposition analyses show that the merged dataset successfully corrects the low bias in the model while preserving its spatial pattern, resulting in very good agreement with MODIS in both magnitude and spatio-temporal variability. The low bias is reduced from 0.10 in GEOS-Chem AOD to 0.04 in the merged data averaged over East China, and the correlation in the seasonal and interannual variability between MODIS and merged AOD is well above 0.75 for most regions. Comparisons between the merged and AERONET data also show an overall small bias and high correlation. The merged dataset reveals four major pollution hot spots in China, including the North China Plain, the Yangtze River Delta, the Pearl River Delta and the Sichuan Basin, consistent with previous works. AOD peaks in spring-summer over the North China Plain and Yangtze River Delta and in spring over the Pearl River Delta, with no distinct seasonal cycle over the Sichuan Basin. The merged AOD has the largest difference from MODIS over the Sichuan Basin. We also discuss possible benefits of visibility based AOD data that correct the sampling bias in MODIS retrievals related to cloud-free sampling and misclassified heavy haze conditions.

  9. Lightning NOx emissions over the USA investigated using TES, NLDN, LRLDN, IONS data and the GEOS-Chem model

    Directory of Open Access Journals (Sweden)

    K. E. Pickering

    2009-01-01

    Full Text Available Knowledge of the lightning source of NOx is required to better understand NOx and ozone distributions and changes in the troposphere, the oxidising capacity of the troposphere as well as some of the feedbacks between chemistry and climate change. In this paper, we use the National Lightning Detection (NLDN and the Long Range Lightning Detection Network (LRLDN data as well as the HYPSLIT transport and dispersion model to show the presence of ozone enhanced layers downwind of convective events in the ozone vertical profiles from the Tropospheric Emission Spectrometer (TES instrument over the USA in July 2006. We use the TES dataset in conjunction with ozonesonde measurements from the Intercontinental Chemical Transport Experiment (INTEX Ozonesonde Network Study (IONS 2006 to test the parameterization of the lightning source of NOx in a global chemistry transport model. We find that the global 3-D chemistry transport model GEOS-Chem with a lightning activity calculated with a parameterization based on cloud top height, scaled regionally and monthly to OTD/LIS (Optical Transient Detector/Lightning Imaging Sensor climatology, and with a production of 260 mol NO/Flash captures the ozone enhancements seen by TES, but underestimates their intensities. We show that the model's ability to reproduce the location of the enhancements is due to the fact that this model reproduces the pattern of the convective events occurrence on a daily basis during the summer of 2006, even though it does not well represent the relative distribution of lightning intensities. By imposing an updated lightning NO production value of 520 mol NO/Flash, we decrease the bias between TES and GEOS-Chem over the US in July 2006 by 40%.

  10. Spatio-temporal variability of aerosols over East China inferred by merged visibility-GEOS-Chem aerosol optical depth

    Science.gov (United States)

    Lin, Jintai; Li, Jing

    2016-05-01

    Long-term visibility measurements offer useful information for aerosol and climate change studies. Recently, a new technique to converting visibility measurements to aerosol optical depth (AOD) has been developed on a station-to-station basis (Lin et al., 2014). However, factors such as human observation differences and local meteorological conditions often impair the spatial consistency of the visibility converted AOD dataset. Here we further adopt AOD spatial information from a chemical transport model GEOS-Chem, and merge visibility inferred and modeled early-afternoon AOD over East China on a 0.667° long. × 0.5° lat. grid for 2005-2012. Comparisons with MODIS/Aqua retrieved AOD and subsequent spectral decomposition analyses show that the merged dataset successfully corrects the low bias in the model while preserving its spatial pattern, resulting in very good agreement with MODIS in both magnitude and spatio-temporal variability. The low bias is reduced from 0.10 in GEOS-Chem AOD to 0.04 in the merged data averaged over East China, and the correlation in the seasonal and interannual variability between MODIS and merged AOD is well above 0.75 for most regions. Comparisons between the merged and AERONET data also show an overall small bias and high correlation. The merged dataset reveals four major pollution hot spots in China, including the North China Plain, the Yangtze River Delta, the Pearl River Delta and the Sichuan Basin, consistent with previous works. AOD peaks in spring-summer over the North China Plain and Yangtze River Delta and in spring over the Pearl River Delta, with no distinct seasonal cycle over the Sichuan Basin. The merged AOD has the largest difference from MODIS over the Sichuan Basin. We also discuss possible benefits of visibility based AOD data that correct the sampling bias in MODIS retrievals related to cloud-free sampling and misclassified heavy haze conditions.

  11. Modeling Gas-phase Glyoxal and Associated Secondary Organic Aerosol Formation in a Megacity using WRF/Chem

    Science.gov (United States)

    Wang, K.; Hodzic, A.; Barth, M. C.; Jimenez, J. L.; Volkamer, R.; Ervens, B.; Zhang, Y.

    2011-12-01

    Organic aerosol (OA) as one of a major fine particulate matter in the atmosphere plays an important role in air pollution, human health, and climate forcing. OA is composed of directly emitted primary organic aerosol and chemically produced secondary organic aerosols (SOA). Despite much recent progress in understanding SOA formation, current air quality models cannot explain the magnitude and growth of atmospheric SOA, due to high uncertainties in sources, properties, and chemical reactions of precursors and formation pathways of SOA. Recent laboratory and modeling studies showed that glyoxal may serve as an important SOA precursor in the condensed solution of inorganic or organic aerosol particles (e.g., ammonium sulfate, fulvic acid, and amino acids). In this study, the Weather Research and Forecasting model with chemistry (WRF/Chem) is modified to account for the latest observed gas-phase yields of glyoxal from various volatile organic compounds (VOCs) and the associated SOA formation in the aqueous aerosol phase. The SOA formation in the aqueous aerosol phase is implemented using two approaches. In the first approach, two simplified parameterizations are used to represent the lumped particle-phase chemical processes under dark conditions and photochemical surface uptake. In the second approach, more detailed kinetic glyoxal reactions such as reversible glyoxal uptake, dimer formation of glyoxal, and oligomerization are treated and resolved explicitly. The updated WRF/Chem is assessed over the Mexico City and the surrounding region during March 2006 using the MILAGRO campaign data. Various observations such as organic matter from Aerodyne Aerosol Mass Spectrometer and VOCs from Proton-transfer Ion Trap Mass Spectrometry were compared. The preliminary results showed that the addition of the SOA formation from glyoxal in aqueous particles brings SOA predictions into a better agreement with field observations, in particular in presence of high relative humidity

  12. La discrimination : une frontière par rapport à l’intégration

    Directory of Open Access Journals (Sweden)

    Rosita Fibbi

    2010-12-01

    Full Text Available La Suisse s’est dotée d’une politique officielle d’intégration qui s’adresse prioritairement aux nouveaux immigrants. Toutefois les difficultés d’intégration concernent également la jeunesse d’origine immigrée qui réside dans le pays depuis des années. Deux études menées au Forum suisse pour l’étude des migrations et de la population montrent que ces jeunes sont confrontés à la discrimination à l’entrée sur le marché du travail, même lorsqu’ils disposent de qualifications identiques à celles de leurs congénères.Discrimination: a boundary to integrationSwitzerland has developed an official policy of integration with a priority accorded to new immigrants. However, integration difficulties concern also young people of immigrant origins who have lived in the country for a long time. Two studies carried out by the Swiss Forum for the Study of Migrations and the Population show that these young individuals are confronted with discrimination when they seek to enter the work force, even when they dispose of identical qualifications to those of their generation.La discriminación como barrera fronteriza contra la immigraciónSuiza se ha dotado de una política oficial dirigida prioritariamente a los imigrantes recientes. Sin embargo las dificultades de la integración atañen tambien a los jovenes de origen extranjero que residen en el pais desde hace años. Dos estudios realizados por el Foro suizo para el estudio de las migraciones y de la población ponen en evidencia que esos jovenes estan confrontados a la discriminación cuando llegan a la edad de trabajar aunque posean el mismo nivel de cualificación que los autoctonos.

  13. Structural and functional analysis of the symmetrical Type I restriction endonuclease R.EcoR124I(NT.

    Directory of Open Access Journals (Sweden)

    James E Taylor

    Full Text Available Type I restriction-modification (RM systems are comprised of two multi-subunit enzymes, the methyltransferase (∼160 kDa, responsible for methylation of DNA, and the restriction endonuclease (∼400 kDa, responsible for DNA cleavage. Both enzymes share a number of subunits. An engineered RM system, EcoR124I(NT, based on the N-terminal domain of the specificity subunit of EcoR124I was constructed that recognises the symmetrical sequence GAAN(7TTC and is active as a methyltransferase. Here, we investigate the restriction endonuclease activity of R. EcoR124I(NTin vitro and the subunit assembly of the multi-subunit enzyme. Finally, using small-angle neutron scattering and selective deuteration, we present a low-resolution structural model of the endonuclease and locate the motor subunits within the multi-subunit enzyme. We show that the covalent linkage between the two target recognition domains of the specificity subunit is not required for subunit assembly or enzyme activity, and discuss the implications for the evolution of Type I enzymes.

  14. The Retrovirus pol Gene Encodes a Product Required for DNA Integration: Identification of a Retrovirus int Locus

    Science.gov (United States)

    Panganiban, Antonito T.; Temin, Howard M.

    1984-12-01

    We mutagenized cloned spleen necrosis virus DNA to identify a region of the retrovirus genome encoding a polypeptide required for integration of viral DNA. Five plasmids bearing different lesions in the 3' end of the pol gene were examined for the ability to integrate or replicate following transfection of chicken embryo fibroblasts. Transfection with one of these DNAs resulted in the generation of mutant virus incapable of integrating but able to replicate at low levels; this phenotype is identical to that of mutants bearing alterations in the cis-acting region, att. To determine whether the 3' end of the pol gene encodes a protein that interacts with att, we did a complementation experiment. Cells were first infected with an att- virus and then superinfected with the integration-deficient virus containing a lesion in the pol gene and a wild-type att site. The results showed that the att- virus provided a trans-acting function allowing integration of viral DNA derived from the mutant bearing a wild-type att site. Thus, the 3' end of the pol gene serves as an ``int'' locus and encodes a protein mediating integration of retrovirus DNA through interaction with att.

  15. ConfChem Conference on Flipped Classroom: Reclaiming Face Time--How an Organic Chemistry Flipped Classroom Provided Access to Increased Guided Engagement

    Science.gov (United States)

    Trogden, Bridget G.

    2015-01-01

    Students' active engagement is one of the most critical challenges to any successful learning environment. The blending of active engagement along with rich, meaningful content is necessary for chemical educators to re-examine the purpose of the chemistry classroom. The Spring 2014 ConfChem conference, Flipped Classroom, was held from May 9 to…

  16. Note: Derivation of two-photon circular dichroism—Addendum to “Two-photon circular dichroism” [J. Chem. Phys. 62, 1006 (1975)

    Energy Technology Data Exchange (ETDEWEB)

    Friese, Daniel H., E-mail: daniel.h.friese@uit.no [Department of Chemistry, Centre for Theoretical and Computational Chemistry CTCC, University of Tromsø, N-9037 Tromsø (Norway)

    2015-09-07

    This addendum shows the detailed derivation of the fundamental equations for two-photon circular dichroism which are given in a very condensed form in the original publication [I. Tinoco, J. Chem. Phys. 62, 1006 (1975)]. In addition, some minor errors are corrected and some of the derivations in the original publication are commented.

  17. University-School Partnerships: On the Impact on Students of Summer Schools (for School Students Aged 17-18) Run by Bristol ChemLabs

    Science.gov (United States)

    Shaw, A. J.; Harrison, T. G.; Croker, S. J.; Medley, M.; Sellou, L.; Shallcross, K. L.; Williams, S, J.; Grayson, D. J.; Shallcross, D. E.

    2010-01-01

    Chemistry summer schools for 17-18 year old school students in the UK were run by Bristol ChemLabS, a Centre for Excellence in Teaching and Learning in Chemistry at the University of Bristol. Students attending were all studying Chemistry at post-16 level (A level in the UK) and experienced not only new practical techniques but also lectures on…

  18. QSAR pre-screen of 70,983 substances for genotoxic carcinogenicity, mutagenicity and developmental toxicity in the EU FP7 project ChemScreen

    DEFF Research Database (Denmark)

    Wedebye, Eva Bay; Dybdahl, Marianne; Nikolov, Nikolai Georgiev;

    2014-01-01

    The focus of the EU FP7 project ChemScreen, which was completed by the end of 2013, was to generate alternative testing methods for reproductive toxicity under REACH. If found adequate, QSARs can be applied in REACH as a replacement for animal tests. As no testing for reproductive effects should be...

  19. E4CHEM. A simulation program for the fate of chemicals in the environment. Handbook. User`s guide and description. Version 3.6. December 1995

    Energy Technology Data Exchange (ETDEWEB)

    Brueggemann, R. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Projektgruppe Umweltgefaehrdungspotentiale von Chemikalien; Drescher-Kaden, U. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Projektgruppe Umweltgefaehrdungspotentiale von Chemikalien; Muenzer, B. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Projektgruppe Umweltgefaehrdungspotentiale von Chemikalien

    1996-02-01

    The predominant aims of E4CHEM are: Deterministic description of the chemical`s behavior in the environment with varying ecoparameters including the special aspects; Behavior of the same chemical in different compartments; Behavior of different chemicals in the same compartment with the same ecoparameters; Tracing back of chemicals detected in the environment to the possible source by means of check procedures like in EXWAT, one of the E4CHEM models; Discharge of the user from extensive calculation operations; Interpretation of experimental results. In combination with statistics and algebraic tools (lattice theory) but not included in E4CHEM yet: Selection of descriptors as tool for priority setting; Identification and ranking of chemicals according to their risk to the environment by comparing descriptors within descriptor matrices about the behavior of chemicals deived from the different models. Furthermore: Identification of chemical applicable as reference substances with respect to environmental behavior. The program E4CHEM is described in this manual. (orig./SR)

  20. ChemEd X Data: Exposing Students to Open Scientific Data for Higher-Order Thinking and Self-Regulated Learning

    Science.gov (United States)

    Eklund, Brandon; Prat-Resina, Xavier

    2014-01-01

    ChemEd X Data is an open web tool that collects and curates physical and chemical data of hundreds of substances. This tool allows students to navigate, select, and graphically represent data such as boiling and melting points, enthalpies of combustion, and heat capacities for hundreds of molecules. By doing so, students can independently identify…

  1. Comment on "Rethinking first-principles electron transport theories with projection operators: The problems caused by partitioning the basis set" [J. Chem. Phys. 139, 114104 (2013)

    DEFF Research Database (Denmark)

    Brandbyge, Mads

    2014-01-01

    In a recent paper Reuter and Harrison [J. Chem. Phys.139, 114104 (2013)] question the widely used mean-field electron transport theories, which employ nonorthogonal localized basis sets. They claim these can violate an “implicit decoupling assumption,” leading to wrong results for the current...

  2. Multiyear applications of WRF/Chem over continental U.S.: Model evaluation, variation trend, and impacts of boundary conditions

    Science.gov (United States)

    Yahya, Khairunnisa; He, Jian; Zhang, Yang

    2015-12-01

    Multiyear applications of an online-coupled meteorology-chemistry model allow an assessment of the variation trends in simulated meteorology, air quality, and their interactions to changes in emissions and meteorology, as well as the impacts of initial and boundary conditions (ICONs/BCONs) on simulated aerosol-cloud-radiation interactions over a period of time. In this work, the Weather Research and Forecasting model with Chemistry version 3.4.1 (WRF/Chem v. 3.4.1) with the 2005 Carbon Bond mechanism coupled with the Volatility Basis Set module for secondary organic aerosol formation (WRF/Chem-CB05-VBS) is applied for multiple years (2001, 2006, and 2010) over continental U.S. This work also examines the changes in simulated air quality and meteorology due to changes in emissions and meteorology and the model's capability in reproducing the observed variation trends in species concentrations from 2001 to 2010. In addition, the impacts of the chemical ICONs/BCONs on model predictions are analyzed. ICONs/BCONs are downscaled from two global models, the modified Community Earth System Model/Community Atmosphere model version 5.1 (CESM/CAM v5.1) and the Monitoring Atmospheric Composition and Climate model (MACC). The evaluation of WRF/Chem-CB05-VBS simulations with the CESM ICONs/BCONs for 2001, 2006, and 2010 shows that temperature at 2 m (T2) is underpredicted for all three years likely due to inaccuracies in soil moisture and soil temperature, resulting in biases in surface relative humidity, wind speed, and precipitation. With the exception of cloud fraction, other aerosol-cloud variables including aerosol optical depth, cloud droplet number concentration, and cloud optical thickness are underpredicted for all three years, resulting in overpredictions of radiation variables. The model performs well for O3 and particulate matter with diameter less than or equal to 2.5 (PM2.5) for all three years comparable to other studies from literature. The model is able to

  3. Application of online-coupled WRF/Chem-MADRID in East Asia: Model evaluation and climatic effects of anthropogenic aerosols

    Science.gov (United States)

    Liu, Xu-Yan; Zhang, Yang; Zhang, Qiang; He, Ke-Bin

    2016-01-01

    The online-coupled Weather Research and Forecasting model with Chemistry with the Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution (referred to as WRF/Chem-MADRID) is applied to simulate meteorological fields, air quality, and the direct and indirect effects of anthropogenic aerosols over East Asia in four months (January, April, July, and October) in 2008. Model evaluation against available surface and satellite measurements shows that despite some model biases, WRF/Chem-MADRID is able to reproduce reasonably well the spatial and seasonal variations of most meteorological fields and chemical concentrations. Large model biases for chemical concentrations are attributed to uncertainties in emissions and their spatial and vertical allocations, simulated meteorological fields, imperfectness of model representations of aerosol formation processes, uncertainties in the observations based on air pollution index, and the use of a coarse grid resolution. The results show that anthropogenic aerosols can reduce net shortwave flux at the surface by up to 40.5-57.2 W m-2, Temperature at 2-m by up to 0.5-0.8 °C, NO2 photolytic rates by up to 0.06-0.1 min-1 and the planetary boundary layer height by up to 83.6-130.4 m. Anthropogenic aerosols contribute to the number concentrations of aerosols by up to 6.2-8.6 × 104 cm-3 and the surface cloud concentration nuclei at a supersaturation of 0.5% by up to 1.0-1.6 × 104 cm-3. They increase the column cloud droplet number concentrations by up to 3.6-11.7 × 108 cm-2 and cloud optical thickness by up to 19.8-33.2. However, anthropogenic aerosols decrease daily precipitation in most areas by up to 3.9-18.6 mm during the 4 months. These results indicate the importance of anthropogenic aerosols in modulating regional climate changes in East Asia through aerosol direct and indirect effects, as well as the need to further improve the performance of online-coupled models.

  4. Trans-Pacific transport and evolution of aerosols: evaluation of quasi-global WRF-Chem simulation with multiple observations

    Science.gov (United States)

    Hu, Zhiyuan; Zhao, Chun; Huang, Jianping; Leung, L. Ruby; Qian, Yun; Yu, Hongbin; Huang, Lei; Kalashnikova, Olga V.

    2016-05-01

    A fully coupled meteorology-chemistry model (WRF-Chem, the Weather Research and Forecasting model coupled with chemistry) has been configured to conduct quasi-global simulation for 5 years (2010-2014) and evaluated with multiple observation data sets for the first time. The evaluation focuses on the simulation over the trans-Pacific transport region using various reanalysis and observational data sets for meteorological fields and aerosol properties. The simulation generally captures the overall spatial and seasonal variability of satellite retrieved aerosol optical depth (AOD) and absorbing AOD (AAOD) over the Pacific that is determined by the outflow of pollutants and dust and the emissions of marine aerosols. The assessment of simulated extinction Ångström exponent (EAE) indicates that the model generally reproduces the variability of aerosol size distributions as seen by satellites. In addition, the vertical profile of aerosol extinction and its seasonality over the Pacific are also well simulated. The difference between the simulation and satellite retrievals can be mainly attributed to model biases in estimating marine aerosol emissions as well as the satellite sampling and retrieval uncertainties. Compared with the surface measurements over the western USA, the model reasonably simulates the observed magnitude and seasonality of dust, sulfate, and nitrate surface concentrations, but significantly underestimates the peak surface concentrations of carbonaceous aerosol likely due to model biases in the spatial and temporal variability of biomass burning emissions and secondary organic aerosol (SOA) production. A sensitivity simulation shows that the trans-Pacific transported dust, sulfate, and nitrate can make significant contribution to surface concentrations over the rural areas of the western USA, while the peaks of carbonaceous aerosol surface concentrations are dominated by the North American emissions. Both the retrievals and simulation show small

  5. Trans-Pacific transport and evolution of aerosols: evaluation of quasi-global WRF-Chem simulation with multiple observations

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Zhiyuan; Zhao, Chun; Huang, Jianping; Leung, Lai-Yung R.; Qian, Yun; Yu, Hongbin; Huang , Lei; Kalashnikova, O.

    2016-05-10

    A fully coupled meteorology-chemistry model (WRF-Chem) has been configured to conduct quasi-global simulation for the 5 years of 2010-2014 and evaluated with multiple observation datasets for first time. The simulation over the transpacific transport region is evaluated using various reanalysis and observational datasets for meteorological fields and aerosol properties. In general, precipitation and winds are well simulated by the model. The simulation captures the overall spatial and seasonal variability of satellite retrieved aerosol optical depth (AOD) and absorbing AOD (AAOD) over the Pacific that is determined by the outflows of pollutants and dust and the emissions of marine aerosols. The assessment of simulated extinction Angstrom exponent (EAE) indicates that the model generally reproduces the variability of aerosol size distributions. In addition, the vertical profile of aerosol extinction and its seasonality over the Pacific that are dominated by marine aerosols near the surface and the outflow of pollutants and dust above 4 km are also well simulated. The difference between the simulation and satellite retrievals can be mainly attributed to model biases in estimating marine aerosol emissions as well as the satellite sampling and retrieval uncertainties. Compared with the surface measurements over the western U.S., the model reproduces the observed magnitude and seasonality of dust, sulfate, and nitrate surface concentrations, but significantly underestimates the peak surface concentrations of carbonaceous aerosol likely due to model biases in the spatial and temporal variability of biomass burning emissions and secondary organic aerosol (SOA) production. A sensitivity simulation shows that the transpacific transported dust, sulfate, and nitrate can make significant contribution to surface concentrations over the rural areas of the western U.S., while the peaks of carbonaceous aerosol surface concentrations are dominated by the North American emissions

  6. Four Dimensional (4-D BioChemInfoPhysics Models of Cardiac Cellular and Sub-Cellular Vibrations (Oscillations

    Directory of Open Access Journals (Sweden)

    Chang-Hua Zou

    2009-01-01

    Full Text Available Problem statement: Cardiovascular Diseases (CVD continued to be the leading cause of death. Failure or abnormal cardiac cellular or sub-cellular vibrations (oscillations could lead failure or abnormal heart beats that could cause CVD. Understanding the mechanisms of the vibrations (oscillations could help to prevent or to treat the diseases. Scientists have studied the mechanisms for more than 100 years. To our knowledge, the mechanisms are still unclear today. In this investigation, based on published data or results, conservation laws of the momentum as well as the energy, in views of biology, biochemistry, informatics and physics (BioChemInfoPhysics, we proposed our models of cardiac cellular and sub-cellular vibrations (oscillations of biological components, such as free ions in Biological Fluids (BF, Biological Membranes (BM, Ca++H+ (Ca++ and Na+K+ ATPases, Na+Ca++ exchangers (NCX, Ca++ carriers and myosin heads. Approach: Our models were described with 4-D (x, y, z, t or r, ?, z, t momentum transfer equations in mathematical physics. Results: The momentum transfer equations were solved with free and forced, damped, un-damped and over-damped, vibrations (oscillations. The biological components could be modeled as resonators or vibrators (oscillators, such as liquid plasmas, membranes, active springs, passive springs and active swings. Conclusion: We systematically provided new insights of automation (ignition and maintain, transportation, propagation and orientation of the cardiac cellular and sub-cellular vibrations (oscillations and resonances, with our BioChemInfoPhysics models of 4-D momentum transfer equations. Our modeling results implied: Auto-rhythmic cells (Sinoatrial Node Cells (SANC, Atrioventricular Node Cells (AVNC, Purkinje fibers, non-Auto-rhythmic ventricular myocytes and their Sarcoplasmic Reticulums (SR work as Biological Liquid Plasma Resonators (BLPR. The resonators were

  7. Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

    Directory of Open Access Journals (Sweden)

    Q. Yang

    2011-12-01

    Full Text Available This study assesses the ability of the recent chemistry version (v3.3 of the Weather Research and Forecasting (WRF-Chem model to simulate boundary layer structure, aerosols, stratocumulus clouds, and energy fluxes over the Southeast Pacific Ocean. Measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx and satellite retrievals (i.e., products from the MODerate resolution Imaging Spectroradiometer (MODIS, Clouds and Earth's Radiant Energy System (CERES, and GOES-10 are used for this assessment. The Morrison double-moment microphysics scheme is newly coupled with interactive aerosols in the model. The 31-day (15 October–16 November 2008 WRF-Chem simulation with aerosol-cloud interactions (AERO hereafter is also compared to a simulation (MET hereafter with fixed cloud droplet number concentrations in the microphysics scheme and simplified cloud and aerosol treatments in the radiation scheme. The well-simulated aerosol quantities (aerosol number, mass composition and optical properties, and the inclusion of full aerosol-cloud couplings lead to significant improvements in many features of the simulated stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness. In addition to accounting for the aerosol direct and semi-direct effects, these improvements feed back to the simulation of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengthens the temperature and humidity gradients within the capping inversion layer and lowers the marine boundary layer (MBL depth by 130 m from that of the MET simulation. These differences are associated with weaker entrainment and stronger mean subsidence at the top of the MBL in AERO. Mean top-of-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with

  8. Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

    Energy Technology Data Exchange (ETDEWEB)

    Yang Q.; Lee Y.; Gustafson Jr., W. I.; Fast, J. D.; Wang, H.; Easter, R. C.; Morrison, H.; Chapman, E. G.; Spak, S. N.; Mena-Carrasco, M. A.

    2011-12-02

    This study assesses the ability of the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model to simulate boundary layer structure, aerosols, stratocumulus clouds, and energy fluxes over the Southeast Pacific Ocean. Measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals (i.e., products from the MODerate resolution Imaging Spectroradiometer (MODIS), Clouds and Earth's Radiant Energy System (CERES), and GOES-10) are used for this assessment. The Morrison double-moment microphysics scheme is newly coupled with interactive aerosols in the model. The 31-day (15 October-16 November 2008) WRF-Chem simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations in the microphysics scheme and simplified cloud and aerosol treatments in the radiation scheme. The well-simulated aerosol quantities (aerosol number, mass composition and optical properties), and the inclusion of full aerosol-cloud couplings lead to significant improvements in many features of the simulated stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness. In addition to accounting for the aerosol direct and semi-direct effects, these improvements feed back to the simulation of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengthens the temperature and humidity gradients within the capping inversion layer and lowers the marine boundary layer (MBL) depth by 130 m from that of the MET simulation. These differences are associated with weaker entrainment and stronger mean subsidence at the top of the MBL in AERO. Mean top-of-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with

  9. Testosterone and farnesoid X receptor agonist INT-747 counteract high fat diet-induced bladder alterations in a rabbit model of metabolic syndrome.

    Science.gov (United States)

    Morelli, Annamaria; Comeglio, Paolo; Filippi, Sandra; Sarchielli, Erica; Cellai, Ilaria; Vignozzi, Linda; Yehiely-Cohen, Ravit; Maneschi, Elena; Gacci, Mauro; Carini, Marco; Adorini, Luciano; Vannelli, Gabriella B; Maggi, Mario

    2012-10-01

    In the male, metabolic syndrome (MetS) is associated to an increased risk of benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS). A recently established rabbit model of high fat diet (HFD)-induced MetS showed hypogonadism and the presence of prostate gland alterations, including inflammation, hypoxia and fibrosis. The present study investigated whether HFD-induced MetS might also alter bladder structure and function. Testosterone and the farnesoid X receptor (FXR) agonist INT-747, were evaluated for possible effects on HFD bladder. MetS rabbits develop bladder alterations, including fibrosis (reduced muscle/fiber ratio), hypoxia [2-fold increase as compared to regular diet (RD) group], low-grade inflammation (increased leukocyte infiltration and inflammatory markers) and RhoA/ROCK hyperactivity. Bladder strips from HFD rabbits, pre-contracted with carbachol, showed an overactive response to the selective ROCK inhibitor Y-27632. All these HFD-induced bladder alterations were partially blunted by testosterone and almost completely reverted by INT-747. Both treatments prevented some MetS features (glucose intolerance and visceral fat increase), thus suggesting that their effects on bladder could be ascribed to an improvement of the metabolic and/or hypogonadal state. However, a pathogenetic role for hypogonadism has been ruled out as GnRH analog-induced hypogonadal rabbits, fed a regular diet, did not show any detectable bladder alterations. In addition, INT-747 did not revert the MetS-induced hypogonadal state. FXR mRNA was highly expressed in rabbit bladder and positively associated with visceral fat increase. A direct effect of INT-747 on bladder smooth muscle was further suggested by inhibition of RhoA/ROCK-mediated activity by in vitro experiments on isolated cells. In conclusion, HFD-related MetS features are associated to bladder derangements, which are ameliorated by testosterone or INT-747 administration. INT-747 showed the most marked

  10. IntNetDB v1.0: an integrated protein-protein interaction network database generated by a probabilistic model

    Directory of Open Access Journals (Sweden)

    Han Jing-Dong J

    2006-11-01

    Full Text Available Abstract Background Although protein-protein interaction (PPI networks have been explored by various experimental methods, the maps so built are still limited in coverage and accuracy. To further expand the PPI network and to extract more accurate information from existing maps, studies have been carried out to integrate various types of functional relationship data. A frequently updated database of computationally analyzed potential PPIs to provide biological researchers with rapid and easy access to analyze original data as a biological network is still lacking. Results By applying a probabilistic model, we integrated 27 heterogeneous genomic, proteomic and functional annotation datasets to predict PPI networks in human. In addition to previously studied data types, we show that phenotypic distances and genetic interactions can also be integrated to predict PPIs. We further built an easy-to-use, updatable integrated PPI database, the Integrated Network Database (IntNetDB online, to provide automatic prediction and visualization of PPI network among genes of interest. The networks can be visualized in SVG (Scalable Vector Graphics format for zooming in or out. IntNetDB also provides a tool to extract topologically highly connected network neighborhoods from a specific network for further exploration and research. Using the MCODE (Molecular Complex Detections algorithm, 190 such neighborhoods were detected among all the predicted interactions. The predicted PPIs can also be mapped to worm, fly and mouse interologs. Conclusion IntNetDB includes 180,010 predicted protein-protein interactions among 9,901 human proteins and represents a useful resource for the research community. Our study has increased prediction coverage by five-fold. IntNetDB also provides easy-to-use network visualization and analysis tools that allow biological researchers unfamiliar with computational biology to access and analyze data over the internet. The web interface of

  11. Periodicity and map for discovery of new ionic liquids

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Suojiang

    2006-01-01

    [1]Trohalaki,S.,Pachter,R.,Drake,G.W.,Hawkins,T.,Quantitative structure-property relationships for melting points and densities of ionic liquids,Energy & Fuels,2005,19:279-284.[2]Holbery,J.D.,Seddon,K.R.,The phase behavior of 1-alkyl-3-methylimidazolium tetrafluoroborates,ionic liquids and ionic liquid crystals,J.Chem.Soc.Dalton Trans.,1999,13:2133-2139.[3]Katritzky,A.R.,Lomaka,A.,Petrukhin,R.et al.,QSPR correlation of the melting point for pyridinium bromides,potential ionic liquids,J.Chem.Inf.Comput.Sci.,2002,42:71-74.[4]Katritzky,A.R.,Jain,R.,Lomaka,A.et al.,Correlation of the melting points of potential ionic liquids (imidazolium bromides and benzimidazolium bromides) using the CODESSA program,J.Chem.Inf.Comput.Sci.,2002,42:225-231.[5]Eike,D.M.,Brennecke,J.F.,Maginn,E.J.,Predicting melting points of quaternary ammonium ionic liquids,Green Chemistry,2003,5:323-328.[6]Dupont,J.,Souza,R.F.,Suarez,A.Z.,Ionic liquid (molten salt) phase organometallic catalysis,J.Chem.Rev.,2002,102:3667-3692.[7]Turner,E.A.,Pye,C.C.,Singer,R.D.,Use of ab initio calculations toward the rational design of room temperature ionic liquids,J.Phys.Chem.A,2003,107(13):2277-2288.[8]Morrow,T.I.,Maginn,E.J.,Molecular dynamics study of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate,J.Phys.Chem.B,2002,106:12807-12813.[9]Cadena,C.,Antony,J.L.,Shah,J.K.et al.,Why is CO2 so soluble in imidazolium-based ionic liquids? J.Am.Chem.Soc.,2004,126(16):5300-5308.[10]Liu,Z.,Huang,S.,Wang,W.,A refined force field for molecular simulation of imidazolium-based ionic liquids,J.Phys.Chem.B,2004,108(34):12978-12989.[11]Earle,M.J,Seddon,K.R.,Ionic liquids,green solvents for the future,Pure Appl.Chem.,2000,72(7):1391-1398.[12]Mendeleev on periodicity:I and II,http://www.rod.beavon.clara.net/periodic1.htm[13]Hoffmann,R.,Building bridges between inorganic and organic chemistry,Angew.Chem.Int.Ed.Engl.,1982,21(10):711-800.

  12. Comment on ``Unified explanation of the anomalous dynamic properties of highly asymmetric polymer blends'' [J. Chem. Phys. 138, 054903 (2013)

    Science.gov (United States)

    Colmenero, J.

    2013-05-01

    In a recent paper by Ngai and Capaccioli ["Unified explanation of the anomalous dynamic properties of highly asymmetric polymer blends," J. Chem. Phys. 138, 054903 (2013), 10.1063/1.4789585] the authors claimed that the so-called coupling model (CM) provides a unified explanation of all dynamical anomalies that have been reported for dynamically asymmetric blends over last ten years. Approximately half of the paper is devoted to chain-dynamic properties involving un-entangled polymers. According to the authors, the application of the CM to these results is based on the existence of a crossover at a time tc ≈ 1-2 ns of the magnitudes describing chain-dynamics. Ngai and Capaccioli claimed that the existence of such a crossover is supported by the neutron scattering and MD-simulation results, corresponding to the blend poly(methyl methacrylate)/poly(ethylene oxide), by Niedzwiedz et al. [Phys. Rev. Lett. 98, 168301 (2007), 10.1103/PhysRevLett.98.168301] and Brodeck et al. [Macromolecules 43, 3036 (2010), 10.1021/ma902820a], respectively. Being one of the authors of these two papers, I will demonstrate here that there is no evidence supporting such a crossover in the data reported in these papers.

  13. Phase transformation of poled "chem-prep" PZT 95/5-2Nb ceramic under quasi-static loading conditions.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Moo Yul; Montgomery, Stephen Tedford; Hofer, John H.

    2004-10-01

    Specimens of poled 'chem-prep' PNZT ceramic from batch HF803 were tested under hydrostatic, uniaxial, and constant stress difference loading conditions at three temperatures of -55, 25, and 75 C and pressures up to 500 MPa. The objective of this experimental study was to obtain the electro-mechanical properties of the ceramic and the criteria of FE (Ferroelectric) to AFE (Antiferroelectric) phase transformations so that grain-scale modeling efforts can develop and test models and codes using realistic parameters. The poled ceramic undergoes anisotropic deformation during the transition from a FE to an AFE structure. The lateral strain measured parallel to the poling direction was typically 35 % greater than the strain measured perpendicular to the poling direction. The rates of increase in the phase transformation pressures per temperature changes were practically identical for both unpoled and poled PNZT HF803 specimens. We observed that the retarding effect of temperature on the kinetics of phase transformation appears to be analogous to the effect of shear stress. We also observed that the FE-to-AFE phase transformation occurs in poled ceramic when the normal compressive stress, acting perpendicular to a crystallographic plane about the polar axis, equals the hydrostatic pressure at which the transformation otherwise takes place.

  14. Evaluating Observational Constraints on N2O Emissions via Information Content Analysis Using GEOS-Chem and its Adjoint

    Science.gov (United States)

    Wells, K. C.; Millet, D. B.; Bousserez, N.; Henze, D. K.; Chaliyakunnel, S.; Griffis, T. J.; Dlugokencky, E. J.; Prinn, R. G.; O'Doherty, S.; Weiss, R. F.; Dutton, G. S.; Elkins, J. W.; Krummel, P. B.; Langenfelds, R. L.; Steele, P.

    2015-12-01

    Nitrous oxide (N2O) is a long-lived greenhouse gas with a global warming potential approximately 300 times that of CO2, and plays a key role in stratospheric ozone depletion. Human perturbation of the nitrogen cycle has led to a rise in atmospheric N2O, but large uncertainties exist in the spatial and temporal distribution of its emissions. Here we employ a 4D-Var inversion framework for N2O based on the GEOS-Chem chemical transport model and its adjoint to derive new constraints on the space-time distribution of global land and ocean N2O fluxes. Based on an ensemble of global surface measurements, we find that emissions are overestimated over Northern Hemisphere land areas and underestimated in the Southern Hemisphere. Assigning these biases to particular land or ocean regions is more difficult given the long lifetime of N2O. To quantitatively evaluate where the current N2O observing network provides local and regional emission constraints, we apply a new, efficient information content analysis technique involving radial basis functions. The technique yields optimal state vector dimensions for N2O source inversions, with model grid cells grouped in space and time according to the resolution that can actually be provided by the network of global observations. We then use these optimal state vectors in an analytical inversion to refine current top-down emission estimates.

  15. Determination of thin noble metal layers using laser ablation ICP-MS: An analytical tool for NobleChem technology

    International Nuclear Information System (INIS)

    Intergranular stress corrosion cracking (SCC) of reactor internals and recirculation piping is a matter of concern in boiling water reactors (BWR). SCC is basically an anodic dissolution of the metal grain boundaries if these are susceptible either because of the failure to stress relieve welds in un-stabilized steel where the grain boundaries become depleted in chromium, or under irradiation where migration of chromium and other impurities away from or to the grain boundaries renders them sensitive to dissolution. To mitigate SCC, the electrochemical corrosion potential (ECP) of the structural materials in the BWR environment needs to be lowered 2 and H2O2 by the injection of a sufficiently large amount of H2 to the feedwater. This technique can be very effective, but it has the undesirable side effect of increasing the radiation level in the main steam by a factor of 4 to 5. NobleChem has been developed and patented by General Electric Company and is a more effective method of achieving a low ECP value at lower hydrogen injection rates without negative side effects of HWC. In this process noble metals (Pt, Rh) are injected into the feedwater (typically during the reactor shut-down), which then deposit on the structural component surfaces and on fuel. Noble metals are electrocatalysts that efficiently recombine O2 and H2O2 with H2 on the metal surface. With NobleChem/Low HWC, the component surface oxidant concentration becomes zero as soon as the bulk reactor water reaches a stoichiometric excess hydrogen condition. The SCC mitigation effectiveness of NobleChem is crucially dependent on achieving a sufficiently high noble metal concentration of ca. 0.1 μg/cm2 on the critical component and crack flank surfaces. In order to study and understand the transport, (re-)distribution and deposition behaviour of the noble metals in the reactor coolant circuit and to control the SCC mitigation effectiveness of NobleChem, analytical methods determining the local Pt and Rh

  16. Chem-Prep PZT 95/5 for Neutron Generator Applications: Powder Fractionation Study of Production-Scale Powders

    International Nuclear Information System (INIS)

    The Materials Chemistry Department 1846 has developed a lab-scale chem-prep process for the synthesis of PNZT 95/5, referred to as the ''SP'' process (Sandia Process). This process (TSP) has been successfully transferred to and scaled-up by Department 14192 (Ceramics and Glass Department), producing the larger quantities of PZT powder required to meet the future supply needs of Sandia for neutron generator production. The particle size distributions of TSP powders routinely have been found to contain a large particle size fraction that was absent in development (SP) powders. This SAND report documents experimental studies focused on characterizing these particles and assessing their potential impact on material performance. To characterize these larger particles, fractionation of several TSP powders was performed. The ''large particle size fractions'' obtained were characterized by particle size analysis, SEM, and ICP analysis and incorporated into compacts and sintered. Large particles were found to be very similar in structure and composition as the bulk of the powder. Studies showed that the large-size fractions of the powders behave similarly to the non-fractionated powder with respect to the types of microstructural features once sintered. Powders were also compared that were prepared using different post-synthesis processing (i.e. differences in precipitate drying). Results showed that these powders contained different amounts and sizes of porous inclusions when sintered. How this affects the functional performance of the PZT 95/5 material is the subject of future investigations

  17. Module photovoltaïque et ombrages : étude et intégration d'une structure d'équilibrage

    OpenAIRE

    Vighetti, Stéphane; Lembeye, Yves; Ferrieux, Jean-Paul; Barbaroux, Jean

    2010-01-01

    National audience Les systèmes photovoltaïques (PV) actuels nécessitent la mise en série d'un grand nombre de cellules PV pour atteindre la tension nécessaire au convertisseur. Cette mise en série peut, en cas d'ombrage, même faible, impacter tous les modules et causer une perte notable de puissance. De plus, le développement du PV intégré au bâti en zone urbaine met en exergue ces problèmes d'ombrages. Cet article propose d'intégrer une topologie d'électronique de puissance au sein même d...

  18. Serge Paugam (dir.), L’intégration inégale. Force, fragilité et rupture des liens sociaux

    OpenAIRE

    Delmas, Corinne

    2014-01-01

    L’intégration n'est plus assurée, de plus en plus de Français éprouvant le sentiment d’une fragilisation des liens sociaux voire, pour certains, l’expérience d’une rupture partielle ou totale de ces liens. C’est ce que montre cet ouvrage collectif sous la direction de Serge Paugam, qui révèle aussi à quel point les niveaux et les modes d’intégration sont inégalement distribués au sein de la société contemporaine. Il rappelle ainsi le caractère souvent cumulatif des inégalités et la nécessité ...

  19. Intégration fonctionnelle autour des composants quatre quadrants
    Avec l'application à la conversion AC/AC

    OpenAIRE

    Nguyen, Dac-Binh

    2008-01-01

    La thèse porte sur l'intégration fonctionnelle autour des composants commandables bidirectionnels en courant et en tension, avec pour application, la conversion AC-AC à prélèvement sinusoïdal (PFC). La première partie du document de thèse présente la mise en oeuvre d'un gradateur AC-AC à l'aide de dispositifs intégrables. Certains bénéfices sont clairement mis en évidence à travers une analyse fonctionnelle et une validation expérimentale complètes. La seconde partie du mémoire porte sur l'in...

  20. Application d'un SIG à la révision du parcellaire dans le cadre d'aménagements forestiers intégrés

    OpenAIRE

    Bousson, Emmanuelle; Lejeune, Philippe; Rondeux, Jacques

    1998-01-01

    En sylviculture intensive, la mise en oeuvre d’aménagements s’appuie classiquement sur un découpage de la forêt en parcelles, unités de base de la gestion permettant, par une description adéquate, de fournir l’image de l’état actuel de la forêt sur les plans écologique, biologique et sylvicole. Dans le cadre d’une gestion “intégrée” ou “pluri-fonctionnelle” intégrant d’autres paramètres que la seule production ligneuse, il s’avère souvent indispensable de procéder à une révision du parcellair...

  1. Contribution à la conception de circuits intégrés analogiques en technologie CMOS basse tension pour application aux instruments d'observation de la Terre

    OpenAIRE

    Standarovski, Denis

    2005-01-01

    Le présent mémoire de thèse s'inscrit dans la problématique d'intégration de chaînes pour traitement du signal vidéo issu d'un capteur CCD dédiées aux instruments d'observation de la Terre. La solution présentée à travers cette étude consiste à concevoir des circuits intégrés spécifiques (ASIC) analogiques avec des technologies CMOS sub-microniques basse-tension, principalement développées pour les circuits numériques complexes. Dans une première partie, nous présentons le contexte de l'étude...

  2. Jardin interdit au cœur de l’Éden. Conflits d’intérêts dans le Parc National du Manu (Pérou)

    OpenAIRE

    Puygrenier Vargas, Fany

    2014-01-01

    Conçues selon les seuls critères occidentaux pour préserver des écosystèmes mis en péril par la surexploitation des ressources, les aires naturelles protégées sont le théâtre d’enjeux idéologiques, politiques, économiques et sociaux. Instaurées sur des terres habitées, elles sont sources de conflits entre les autorités chargées d’en assurer l’intégrité et des populations locales ayant des pratiques et intérêts propres, divergents de ceux des conservationnistes. C’est par exemple le cas du par...

  3. Comment on "A study of phantom scalar field cosmology using Lie and Noether symmetries" [Int. J. Mod. Phys. D 25 (2016) 1650051

    CERN Document Server

    Paliathanasis, Andronikos; Tsamparlis, Michael

    2016-01-01

    We show that the recent results of \\ [Int. J. Mod. Phys. D 25 (2016) 1650051] on the application of Lie/Noether symmetries in scalar field cosmology are well-known in the literature while the problem could have been solved easily under a coordinate transformation. That follows from the property, that the admitted group of invariant transformations of dynamical system is independent on the coordinate system.

  4. La veille stratégique intégrée: Connaissances, mimétisme, niveau d’aspiration

    OpenAIRE

    Luc Chaput

    2006-01-01

    Le présent article présente un modèle intégré de veille stratégique, méthodologie de base en gestion de projet. Les étapes importantes sont : étalonnage, gestion des connaissances, isomorphisme, aspiration. Le modèle permet de mieux identifier les risques lors des innovations menant à l’application technologique.

  5. Functional Characterization of the Semisynthetic Bile Acid Derivative INT-767, a Dual Farnesoid X Receptor and TGR5 AgonistS⃞

    OpenAIRE

    Rizzo, Giovanni; Passeri, Daniela; Franco, Francesca; Ciaccioli, Gianmario; Donadio, Loredana; Rizzo, Giorgia; Orlandi, Stefano; Sadeghpour, Bahman; Wang, Xiaoxin X.; Jiang, Tao; Levi, Moshe; Pruzanski, Mark; Adorini, Luciano

    2010-01-01

    Two dedicated receptors for bile acids (BAs) have been identified, the nuclear hormone receptor farnesoid X receptor (FXR) and the G protein-coupled receptor TGR5, which represent attractive targets for the treatment of metabolic and chronic liver diseases. Previous work characterized 6α-ethyl-3α,7α-dihydroxy-5β-cholan-24-oic acid (INT-747), a potent and selective FXR agonist, as well as ...

  6. Utilisation des représentations spatiales en Gestion Intégrée des Zones Côtières

    OpenAIRE

    Ritschard, Lucille; Gourmelon, Françoise; Chlous, Frédérique

    2015-01-01

    International audience This article aims to study how mapping contributes to organize and implement Integrated Coastal Zone Management projects. In order to observe the use of spatial representations and better understand the stakeholder's mapping practices a qualitative methodology is used. The results show that mapping was mostly used to structure and stabilize the actor's network. . Cet article vise à interroger les usages des représentations spatiales dans les projets de Gestion Int...

  7. De l’intérêt de la « micro-politique ». Pour en finir avec la sempiternelle coupure pouvoir/société

    OpenAIRE

    Rocca, Jean-Louis

    2010-01-01

    La localisation et la dimension du politique sont des grandes énigmes chinoises. Pour la plupart des observateurs, l'affaire est entendue. Aujourd'hui, il existe une opposition radicale entre pouvoir et la société, l'un essayant d'empêcher l'autre d'imposer et de défendre ses intérêts (...).

  8. (Dés)intégration des modèles existants dans l'enseignement de la littérature à des apprenants de L2 ?

    OpenAIRE

    Marcant, Marie-Dominique

    2013-01-01

    Pour citer cet article : Marcant, Marie-Dominique. 2014. (Dés)intégration des modèles existants dans l'enseignement de la littérature à des apprenants de L2 ?. Actes des 16èmes Rencontres Jeunes Chercheurs en Sciences du Langage : Modèles et modélisation dans les sciences du langage (RJC 2013), 66-79. http://hal.archives-ouvertes.fr/hal-00964884

  9. Comparison of Laser Induced Breakdown Spectroscopy (LIBS) on Martian Meteorite NWA 7034 to ChemCam Observations at Gale Crater, Mars

    Science.gov (United States)

    Gordon, S.; Newsom, H. E.; Agee, C. B.; Santos, A. R.; Clegg, S. M.; Wiens, R. C.; Lasue, J.; Sautter, V.

    2014-12-01

    The ChemCam instrument on board the Mars Science Laboratory (MSL) Curiosity rover uses laser-induced breakdown spectroscopy (LIBS) to analyze rock and soil targets on Mars from up to 7 m away. The Nd:KGW laser can shoot up to 1000 shots at one location and profile up to 1 mm depth into a rock. Identical LIBS instrumentation is located at Los Alamos National Laboratory and was used to analyze martian meteorite NWA 7034, a non-SNC basaltic breccia whose bulk composition matches the martian surface. Initial LIBS analysis of NWA 7034 included observations on two basaltic clasts in the meteorite. Electron microprobe analysis (EPMA) was performed on the two clasts for comparison with elemental compositions measured using LIBS. The two instruments give similar compositions of major oxides within the error of both techniques. EPMA analysis was also completed on three light-toned clasts and a dark-toned clast in the meteorite. The light-toned clasts have Al/Si vs. (Fe+Mg)/Si compositions ranging from felsic to mafic, and the dark-toned clast shows a mafic composition. A Sammon's map was created to compare LIBS data for NWA 7034 and ChemCam targets Stark, Crestaurum, Link, Portage, Jake_M, Mara, Thor_Lake, Coronation, Pearson, and Prebble. This nonlinear statistical mapping technique is used for clustering assessment of LIBS data in two dimensions. The map shows NWA 7034 clustering in its own location, and the closest similar ChemCam rock targets are La_Reine and Ashuamipi, which are both coarse grained targets that have a mafic component consistent with augite. The most similar ChemCam soil targets are the Crestaurum and Portage. Creation of maps with a greater number of targets will show more of the similarities between NWA 7034 and ChemCam target rocks and soils. Further analysis will compare NWA 7034 LIBS data, data from the paired meteorite NWA 7533, and a variety of ChemCam targets that are similar in morphology and texture.

  10. 人类趋化因子受体1(CMKLR1/hChemR23)转基因小鼠对实验性腹膜炎和牙周炎的炎症抑制效应%Attenuation of experimental peritonitis and periodontitis in human chemokine-like receptor 1 ( CMKLR1 or hChemR23 ) transgenic mice

    Institute of Scientific and Technical Information of China (English)

    高丽; Robert Gyurko; Thomas VanDyke

    2012-01-01

    Objective: To prepare a transgenic mouse model with myeloid-selective expression of human chemokine-like receptor 1 (CMKLRl or hChemR23 ) and investigate the in vivo inflammatory response of the particular transgenic mice in induced-peritonitis and perindontitis. Methods; The full-length hChemR23 cDNA and hCD11b promoters were cloned into pcDNA3 plasmid. Purified transgene (2. 9 kb) was used to make transgenic mice at Boston University Transgenic/Knock out Mouse Core Facility. Copy numbers and mRNA level of hChemR23 transgene in the founders were verified by Custom TaqMan Gene Expression Real-time PCR assay. Hemizygous colonies were amplified by out-breeding hChemR23 transgenic males with wide-type FVB females. Transgenic mice were injected intraperitoneally with 1 mL of zymosan A solution ( 1 g/L in PBS). Peritoneal lavage cells slained with PE-conjugated anti-mouse F4/80 and FITC-conjugated anti-mouse Ly6G were analyzed by FACSort. Then 9-0 silk ligature was tied around the first molar to induce a periotontitis mouse model. The distance of eementoenamel junction to the alveolar bone crest ( CEJ-ABC) was calculated to evaluate the alveolar bone loss. Data were analyzed with student' s t-test and variance analysis. Results: One out of the four Fl founders carried the hChemR23 transgene. hChemR23 transgenic mice had reduced 56% fewer positive labeled polymorpho-nuclear neutrophil (PMNs) in peritonitis abdominal lavage fluid as compared with wide-type littermates. In a ligature-induced peirodontitis mouse model, hChemR23 transgenic mice showed decreased alveolar bone loss as compared with WT littermates ( P < 0. 05 ). Conclusion: The hChemR23 transgenic mice over-expressed the hChemR23 at mRNA level and had reduced inflammation in the acute peritonitis and ligature-induced periodontitis model.%目的:构建髓细胞选择性表达人类趋化因子受体1(chemokine receptor-like 1,CMKLR1或human chemerin receptor 23,hChemR23)的转基因小鼠,检测其在小鼠腹

  11. Chem Ed Compacts

    Science.gov (United States)

    Wolf, Walter A., Ed.

    1977-01-01

    Presents a convenient notation for powers of ten and logarithms, a demonstration of the nonstoichiometry of nickel oxide, a simplification for obtaining Russell-Saunders term symbols, and a scheme for biochemistry laboratory experiments. (SL)

  12. Chem Gems & Joules

    Science.gov (United States)

    Mason, Diana S.

    2002-09-01

    Learn about the chemistry (and some physics) of optical discs such as CDs, CD-ROMs, and DVDs from David Birkett (p 1081). Beginning on p 1088, Johnson and Yalkowsky present some neat models (commercial or build-yourself) that assemble of their own accord into appropriate structures for liquid and solid water. Do you need a low-cost, small-scale heating device? How about adapting a soldering iron as described on p 1109? If you are interested in cooperative learning, the comparison with lecturing that begins on p 1131 will provide useful information. The latest in our series commemorating the centenary of the Nobel Prizes begins on p 1055. The many interconnections among the research of prizewinners described in this series provides interesting tidbits to humanize chemical kinetics. Do you have hydrogen peroxide, sulfur, or potassium chromate in your lab or chemical storage area? Learn about hazards of these substances from the letter to the editor on p 1070 and the CLIPs on p 1063, p 1064, and p 1065. Finally, keep up with chemical education news at the ACS and the NSF by reading the statements of candidates for the ACS presidency (p 1036 and p 1037) and the commentary by Ellis on p 1034.

  13. Chem Ed Compacts

    Science.gov (United States)

    Wolf, Walter A., Ed.

    1977-01-01

    Presents classroom and laboratory teaching and demonstration ideas, including a demonstration of optical rotation, automatic potentiometric titration, preparation of radioactive lead, and an organic lab practical in library resources. (SL)

  14. Chem Ed Compacts

    Science.gov (United States)

    Wolf, Walter A., Ed.

    1978-01-01

    Presents teaching notes on the topics of powers of ten notations, physical chemistry projects involving natural products, calorimetry, and solar energy, and learning organic chemistry by playing cards. (SL)

  15. Reduced numbers of mucosal DR(int) macrophages and increased numbers of CD103(+) dendritic cells during anti-TNF-α treatment in patients with Crohn's disease.

    Science.gov (United States)

    Dige, Anders; Magnusson, Maria K; Öhman, Lena; Hvas, Christian Lodberg; Kelsen, Jens; Wick, Mary Jo; Agnholt, Jørgen

    2016-06-01

    Objective Anti-TNF-α treatment constitutes a mainstay in the treatment of Crohn's disease (CD), but its mechanisms of action are not fully understood. We aimed to investigate the effects of adalimumab, a human monoclonal TNF-α antibody, on macrophage (MQ) and dendritic cell (DC) subsets in mucosal biopsies and peripheral blood. Material and methods Intestinal biopsies and blood samples were obtained from 12 different CD patients both before and 4 weeks after the initiation of the induction of adalimumab treatment. Endoscopic disease activity was estimated by the Simple Endoscopic Score for Crohn's Disease. Biopsies were obtained from inflamed and non-inflamed areas. The numbers of lamina propria CD14 (+) DR(int) and CD14 (+) DR(hi) MQs, CD141(+), CD141(-) and CD103(+ )DCs subsets, and circulating monocytes and DCs were analyzed using flow cytometry. Results At baseline, we observed higher numbers of DR(int) MQs and lower numbers of CD103(+ )DCs in inflamed versus non-inflamed mucosa [843 vs. 391/10(5) lamina propria mononuclear cells (LPMCs) (p < 0.05) and 9 vs. 19 × 10(5) LPMCs (p = 0.01), respectively]. After four weeks of adalimumab treatment, the numbers of DR(int) MQs decreased [843 to 379/10(5) LPMCs (p = 0.03)], whereas the numbers of CD103(+ )DCs increased [9-20 × 10(5) LPMCs (p = 0.003)] compared with baseline. In peripheral blood, no alterations were observed in monocyte or DC numbers between baseline and week 4. Conclusions In CD, mucosal inflammation is associated with high numbers of DR(int) MQs and low numbers of CD103(+ )DCs. This composition of intestinal myeloid subsets is reversed by anti-TNF-α treatment. These results suggest that DR(int) MQs play a pivotal role in CD inflammation. PMID:26784676

  16. Virage à gauche et intégration régionale en Amérique latine Shifts to the left and regional integration in Latin America

    Directory of Open Access Journals (Sweden)

    Olivier Dabène

    2011-04-01

    Full Text Available Le virage à gauche de l’Amérique latine ne s’est pas traduit par des avancées significatives de l’intégration régionale. L’option du libre-échange adoptée par les forces politiques centristes qui sont à l’origine de l’intégration a ensuite fortement contraint les choix des candidats à la relance du processus. Les réformes engagées par le Mercosur depuis 2002 mettent en évidence la difficulté qu’ont des présidents de gauche à approfondir l’intégration. Cet article présente les limites du projet de Parlement et du Fonds de convergence, et analyse l’échec du Secrétariat d’assistance technique. Il évoque aussi la concurrence qu’exercent les projets concurrents des Accords de libre-échange avec les États-Unis et l’Alternative bolivarienne pour les Amériques (ALBA de Chávez. La gauche est frileuse concernant la dimension supranationale de l’intégration, mais elle bute aussi sur l’inertie du processus d’intégration.Latin America’s move to the left has not triggered any significant progress in regional integration. Strong historical evidence shows that ECLAC’s regional integration policy, instigated in 1948 and based on industrial complementarity, has not been implemented. Instead, the centrist political parties that supported regional integration have favoured free trade. This particular path severely constrained subsequent candidates from reactivating integration. The reforms undertaken by Mercosur from 2002 onwards demonstrate the difficulties faced by left-wing presidents in their attempts to consolidate integration. This paper discusses the limits of the Parliament and Convergence Fund projects and examines the failure of the Technical Assistance Secretariat. It also refers to the competition between the Free Trade Agreements with the United States and President Chávez’ Bolivarian Alternative for the Americas (ALBA. The left is lukewarm towards the supranational aspect of integration

  17. Modelling atmospheric oxidation of 2-aminoethanol (MEA) emitted from post-combustion capture using WRF-Chem.

    Science.gov (United States)

    Karl, M; Svendby, T; Walker, S-E; Velken, A S; Castell, N; Solberg, S

    2015-09-15

    Carbon capture and storage (CCS) is a technological solution that can reduce the amount of carbon dioxide (CO2) emissions from the use of fossil fuel in power plants and other industries. A leading method today is amine based post-combustion capture, in which 2-aminoethanol (MEA) is one of the most studied absorption solvents. In this process, amines are released to the atmosphere through evaporation and entrainment from the CO2 absorber column. Modelling is a key instrument for simulating the atmospheric dispersion and chemical transformation of MEA, and for projections of ground-level air concentrations and deposition rates. In this study, the Weather Research and Forecasting model inline coupled with chemistry, WRF-Chem, was applied to quantify the impact of using a comprehensive MEA photo-oxidation sequence compared to using a simplified MEA scheme. Main discrepancies were found for iminoethanol (roughly doubled in the detailed scheme) and 2-nitro aminoethanol, short MEA-nitramine (reduced by factor of two in the detailed scheme). The study indicates that MEA emissions from a full-scale capture plant can modify regional background levels of isocyanic acid. Predicted atmospheric concentrations of isocyanic acid were however below the limit value of 1 ppbv for ambient exposure. The dependence of the formation of hazardous compounds in the OH-initiated oxidation of MEA on ambient level of nitrogen oxides (NOx) was studied in a scenario without NOx emissions from a refinery area in the vicinity of the capture plant. Hourly MEA-nitramine peak concentrations higher than 40 pg m(-3) did only occur when NOx mixing ratios were above 2 ppbv. Therefore, the spatial variability and temporal variability of levels of OH and NOx need to be taken into account in the health risk assessment. The health risk due to direct emissions of nitrosamines and nitramines from full-scale CO2 capture should be investigated in future studies. PMID:25958366

  18. Simulated effect of timing and Pt quantity injected on On-line NobleChem application on total fuel liftoff

    International Nuclear Information System (INIS)

    Total liftoff is a measure of fuel performance and a risk indicator for fuel reliability. Fuel operability and license limits are directly related to the expected total lifetime liftoff. AREVA's continued commitment to zero fuel failure is expressed, among other efforts, in the continued development and improvement of its fuel cladding corrosion and crud risk assessment tools. The AREVA models used to assess and predict crud deposition on BWR cores over their lifespan have been refined by the development and incorporation of the PEZOG tool in response to the move in the industry to the On-Line NobleChemTM (OLNC) technology. PEZOG models the platinum-enhanced zirconium oxide growth of fuel cladding when exposed to platinum during operation. Depending on the local chemistry and radiation condition, noble metals act as catalysts for many reactions, including but not limited to hydrogen oxidation and oxygen reduction. OLNC's intention is to catalyze the hydrogen and oxygen recombination reaction for core internals protection. However, research has indicated that noble metals catalyze the oxygen reduction under the chemistry and radiation conditions as experienced in the pores of crud deposits, and hence, can increase the corrosion rate of zirconium alloy cladding. The developed PEZOG module calculates the oxide thickness as a function of platinum injection strategy. The stratified nature of oxide and crud layers formed on fuel cladding surfaces is reflected in the calculations as are the different platinum interaction in each of the layers. This paper presents examples of the evaluation of various aspects of the platinum injection strategies and their influence on the oxide growth enhancement as applied to conditions of a U.S. plant. (authors)

  19. Wet scavenging of soluble gases in DC3 deep convective storms using WRF-Chem simulations and aircraft observations

    Science.gov (United States)

    Bela, Megan M.; Barth, Mary C.; Toon, Owen B.; Fried, Alan; Homeyer, Cameron R.; Morrison, Hugh; Cummings, Kristin A.; Li, Yunyao; Pickering, Kenneth E.; Allen, Dale J.; Yang, Qing; Wennberg, Paul O.; Crounse, John D.; St. Clair, Jason M.; Teng, Alex P.; O'Sullivan, Daniel; Huey, L. Gregory; Chen, Dexian; Liu, Xiaoxi; Blake, Donald R.; Blake, Nicola J.; Apel, Eric C.; Hornbrook, Rebecca S.; Flocke, Frank; Campos, Teresa; Diskin, Glenn

    2016-04-01

    We examine wet scavenging of soluble trace gases in storms observed during the Deep Convective Clouds and Chemistry (DC3) field campaign. We conduct high-resolution simulations with the Weather Research and Forecasting model with Chemistry (WRF-Chem) of a severe storm in Oklahoma. The model represents well the storm location, size, and structure as compared with Next Generation Weather Radar reflectivity, and simulated CO transport is consistent with aircraft observations. Scavenging efficiencies (SEs) between inflow and outflow of soluble species are calculated from aircraft measurements and model simulations. Using a simple wet scavenging scheme, we simulate the SE of each soluble species within the error bars of the observations. The simulated SEs of all species except nitric acid (HNO3) are highly sensitive to the values specified for the fractions retained in ice when cloud water freezes. To reproduce the observations, we must assume zero ice retention for formaldehyde (CH2O) and hydrogen peroxide (H2O2) and complete retention for methyl hydrogen peroxide (CH3OOH) and sulfur dioxide (SO2), likely to compensate for the lack of aqueous chemistry in the model. We then compare scavenging efficiencies among storms that formed in Alabama and northeast Colorado and the Oklahoma storm. Significant differences in SEs are seen among storms and species. More scavenging of HNO3 and less removal of CH3OOH are seen in storms with higher maximum flash rates, an indication of more graupel mass. Graupel is associated with mixed-phase scavenging and lightning production of nitrogen oxides (NOx), processes that may explain the observed differences in HNO3 and CH3OOH scavenging.

  20. Upper troposphere and stratosphere distribution of hydrocarbon species in ACE-FTS measurements and GEOS-Chem simulations

    Science.gov (United States)

    Koo, Ja-Ho; Walker, Kaley A.; Jones, Dylan B. A.; Jones, Ashley; Sheese, Patrick E.; Boone, Chris D.; Bernath, Peter F.; Manney, Gloria L.

    2016-04-01

    Measurements of carbon-containing species, referred to herein as "hydrocarbons", are important components needed for describing and understanding the influence of natural and anthropogenic emissions on atmospheric chemistry. Analysis of the global pattern of hydrocarbons contributes to our understanding of the influence of regional and seasonal variation in air pollution and natural fire events. The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) has monitored trace gases in the upper troposphere and stratosphere based on solar occultation measurements for more than ten years. In this study, we investigate the global pattern of seven "hydrocarbon" species (CO, C2H6, C2H2, HCN, H2CO, CH3OH, and HCOOH) and OCS using the ACE-FTS version 3.5 dataset from 2004 to 2013. All hydrocarbons show strong seasonal variation and regional differences, but the detailed pattern differs according to the speciation of the hydrocarbons. For example, in the Northern Hemisphere, CO, C2H6, and C2H2 show the highest mixing ratios in winter, but high CH3OH and HCOOH appear in summer. In the Southern hemisphere, H2CO, HCN, and HCOOH show high mixing ratios in springtime. These patterns indicate the impact of different emission sources including fuel combustion, wildfire emission, and chemical production. By calculating correlations with CO, these results can provide useful information to characterize each hydrocarbon emission. The ACE-FTS measurements have also been compared with GEOS-Chem output to examine the model performance and spatiotemporal patterns in the simulations.

  1. Impact of various emission control schemes on air quality using WRF-Chem during APEC China 2014

    Science.gov (United States)

    Guo, Jianping; He, Jing; Liu, Hongli; Miao, Yucong; Liu, Huan; Zhai, Panmao

    2016-09-01

    Emission control measures have been implemented to make air quality good enough for Asia-Pacific Economic Cooperation (APEC) China 2014, which provides us with an ideal test-bed to determine how these measures affect air quality in Beijing and surrounding areas. Based on hourly observations at eight monitoring sites of Beijing, the concentrations of other primary atmospheric pollutants during APEC were found to have significantly lower magnitudes than those before APEC, with the exception of a higher O3 concentration. Overall, WRF/Chem reproduced the observed time series of PM2.5, PM10, NO2, CO, and O3 notably well. To investigate the impact of emission control measures on air quality on both local and regional scales, four emission control schemes were developed according to the locations where emission reduction had taken place; the corresponding simulations were subsequently run separately. Scheme S2 (emission control implemented in Beijing) resulted in reductions of 22%, 24%, 10% and 22% for the concentrations of PM2.5, PM10, NO2 and CO, respectively, compared with 14%, 14%, 8%, and 13% for scheme S3 (emission controls implemented from outside of Beijing). This finding indicates that the local emission reduction in Beijing contributes more to the improved air quality in Beijing during APEC China 2014 than does the emission reduction from outside of Beijing. In terms of the impact on the regional scale, the real emission control scheme led to significant reduction of PM2.5 throughout the whole domain. Although the regional impact cannot be completely ignored, both emission reduction measures implemented in Beijing and those implemented outside of Beijing favor greater reduction in PM2.5 in the domains where measurements are presumably taken, as compared with other domains. Therefore, to improve the air quality in Beijing, more coordinated efforts should be made, particularly in the aspect of more stringent reduction and control strategies on pollutant emission

  2. Aerosol-cloud associations over Gangetic Basin during a typical monsoon depression event using WRF-Chem simulation

    Science.gov (United States)

    Sarangi, Chandan; Tripathi, S. N.; Tripathi, Shivam; Barth, Mary C.

    2015-10-01

    To study aerosol-cloud interactions over the Gangetic Basin of India, the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) has been applied to a typical monsoon depression event prevalent between the 23 and 29 August 2009. This event was sampled during the Cloud Aerosol Interaction and Precipitation Enhancement EXperiment (CAIPEEX) aircraft campaign, providing measurements of aerosol and cloud microphysical properties from two sorties. Comparison of the simulated meteorological, thermodynamical, and aerosol fields against satellite and in situ aircraft measurements illustrated that the westward propagation of the monsoon depression and the cloud, aerosol, and rainfall spatial distribution was simulated reasonably well using anthropogenic emission rates from Monitoring Atmospheric Composition and Climate project along with cityZEN projects (MACCity)+Intercontinental Chemical Transport Experiment Phase B anthropogenic emission rates. However,the magnitude of aerosol optical depth was underestimated by up to 50%. A simulation with aerosol emissions increased by a factor of 6 over the CAIPEEX campaign domain increased the simulated aerosol concentrations to values close to the observations, mainly within boundary layer. Comparison of the low-aerosol simulation and high-aerosol simulation for the two sorties illustrated that more anthropogenic aerosols increased the cloud condensing nuclei (CCN) and cloud droplet mass concentrations. The number of simulated cloud droplets increased while the cloud droplet effective radii decreased, highlighting the importance of CCN-cloud feedbacks over this region. The increase in simulated anthropogenic aerosols (including absorbing aerosols) also increased the temperature of air parcels below clouds and thus the convective available potential energy (CAPE). The increase in CAPE intensified the updraft and invigorated the cloud, inducing formation of deeper clouds with more ice-phase hydrometeors for both cases

  3. Regional CO pollution in China simulated by the high-resolution nested-grid GEOS-Chem model

    Directory of Open Access Journals (Sweden)

    D. Chen

    2009-03-01

    Full Text Available An updated version of the nested-grid GEOS-Chem model is developed allowing for higher horizontal (0.5°×0.667° and vertical resolution as compared to global models. CO transport over a heavily polluted region, the Beijing-Tianjin-Hebei (BTH city cluster in China, and the pattern of outflow from East China in summertime are investigated. Comparison of the nested-grid with global models indicates that the fine-resolution nested-grid model is capable of resolving individual cities with high associated emission intensities. The nested-grid model indicates the presence of a high CO column density over the Sichuan Basin in summer, attributable to the low-level stationary vortex associated with the Basin's topographical features. The nested-grid model provides good agreement also with measurements from a suburban monitoring site in Beijing during summer 2005. Tagged CO simulation results suggest that regional emissions make significant contributions to elevated CO levels over Beijing on polluted days and that the southeastward moving cyclones bringing northwest winds to Beijing are the key meteorological mechanisms responsible for dispersion of pollution over Beijing in summer. Overall CO fluxes to the NW Pacific from Asia are found to decrease by a factor of 3–4 from spring to summer. Much of the seasonal change is driven by decreasing fluxes from India and Southeast Asia in summer, while fluxes from East China are only 30% lower in summer than in spring. Compared to spring, summertime outflow from Chinese source regions is strongest at higher latitudes (north of 35° N. The deeper convection in summer transporting CO to higher altitudes where export is more efficient is largely responsible for enhanced export in summer.

  4. Dust-induced radiative feedbacks in north China: A dust storm episode modeling study using WRF-Chem

    Science.gov (United States)

    Liu, Lixia; Huang, Xin; Ding, Aijun; Fu, Congbin

    2016-03-01

    Radiative forcing of dust aerosol and the radiative feedbacks on the planetary boundary layer (PBL) in North China during a typical Asian dust storm in the early April of 2011 was investigated by an online coupled meteorology-chemistry-aerosol model WRF-Chem. Dust-induced daily mean radiative forcing (RF) at the ground surface and in the atmosphere were estimated to be -21.1 W m-2 and 12.7 W m-2, respectively, over Gobi desert, and -13.1 W m-2 and 4.8 W m-2, respectively, in downwind region over the North China Plain (NCP). Comparatively, radiative perturbation on short-wave radiation was approximately twice that on long-wave radiation in magnitude. In the daytime, when solar radiation dominated, the surface cooling and atmospheric heating due to dust increased PBL stability, leading to reductions of PBL height (PBLH) about 90 m and decreases in wind speed up to 0.4 m s-1. On the contrary, the radiative forcing in terrestrial radiation caused an opposite response at night, especially in the downwind region. Although dust emission was repressed by weakened wind speed during daytime, the elevated PBLH along with larger deflation at night lifted more dust particles to higher altitude (by up to 75 m in average), which prolonged dust residence time in the atmosphere and further intensified dust loading in downwind areas. Taking dust radiative feedbacks into consideration notably narrowed gaps between model-predicted air temperature vertical profiles with corresponding observations, suggesting a significant importance of dust-radiation interaction in PBL meteorology during dust storms.

  5. Analyzing the Effects of Dust on Atmospheric Composition over Northwestern China in Spring 2008 Using WRF-Chem

    Science.gov (United States)

    Wang, J.; Allen, D. J.; Pickering, K. E.; Li, Z.

    2014-12-01

    Adjacent to the Taklimakan and Gobi deserts, northwestern China experiences dust storms frequently during the spring season. With the population and industry in northwestern China growing rapidly, anthropogenic pollution also impacts the aerosol composition and therefore optical properties and radiative effects. For instance, NOx emissions from Gansu province increased from ~195 Gg/yr in 2000 to ~323 Gg/yr in 2006 due to the fast growth of transportation vehicles, while SO2 emissions dropped from ~439 Gg/yr to ~338 Gg/yr because flue-gas desulfurization (FGD) devices are widely used in coal-fired powerplants. The WRF-Chem model with CBMZ chemistry mechanism, MOSAIC 8-bins aerosol module and GOCART dust emission algorithm, is applied to simulate the processes responsible for temporal changes in the aerosol distribution, aerosol optical properties and size distribution in Northwestern China due to the impact of dust and anthropogenic emissions during spring 2008, a time period during which an intensive field campaign was conducted at the Zhangye National Climate Observatory (39.082°N, 100.276°E, 1460 m above sea level) of the China Meteorological Administration. This field campaign provided observations of meteorological fields, radiative fluxes, trace gases concentrations, aerosol optical properties, and aerosol size distributions to evaluate the model simulation. The observational data showed a pronounced diurnal variation of trace gases and aerosols: low in the afternoon and high in the morning. Elevated pollutant levels were observed in several dust storms during this campaign. We will investigate the atmospheric processes that are responsible for the atmospheric composition, and assess the relative impact of dust and anthropogenic emissions on local air quality.

  6. La place du groupe de pairs dans l’intégration des nouvelles aides-soignantes dans les EHPAD

    Directory of Open Access Journals (Sweden)

    François Aubry

    2010-12-01

    Full Text Available Cet article propose une problématisation de l’intégration des aides-soignantes dans les organisations gériatriques de type EHPAD, en France, à partir du postulat théorique de l’habilitation, défini par Marcelle Stroobants. Devenir aide-soignante n’est pas uniquement le prolongement continu d’une formation, de l’acquisition d’un diplôme et de l’obtention d’un emploi. Le processus d’intégration des nouvelles aides-soignantes dans l’organisation est une étape informelle fondamentale au fait d’entrer dans le métier. À travers l’analyse de vingt-quatre entretiens biographiques, nous avons pu relever la contradiction entre les propos des acteurs, proposant une vision naturalisée du choix professionnel, et le récit de leur parcours professionnel. Ce décalage met en avant l’importance du processus de construction identitaire par le groupe de pairs. Les différentes approches sociologiques de la compétence ne proposent pas une vision aussi globale que celle de l’habilitation, qui permet un renversement de la perspective individualiste de formation. Dans le prolongement de cette théorie, nous insisterons ainsi sur le rôle central du jugement des pairs, attributif de compétence, pour ce métier fortement dominé socialement.The role of peer group in integration of new nursing’s aides in geriatric nursing homesThis paper proposes a problematization of the integration of nursing’s aides in organizations like geriatric nursing homes in France, from the theoretical premise of “habilitation”, defined by Marcelle Stroobants. Becoming a nursing’s aides not only the continuous extension of training, acquisition of a diploma and getting a job.The process of integrating new nursing’s aides in the organization is a fundamental informal stage in the fact of entering the profession.Through analysis of twenty-four biographical interviews, we could note the contradiction between what actors speech, offering a

  7. Trace element geochemistry (Li, Ba, Sr, and Rb) using Curiosity's ChemCam: Early results for Gale crater from Bradbury Landing Site to Rocknest

    OpenAIRE

    Ollila, Ann M.; Newsom, Horton E.; CLARK , Benton; Wiens, Roger C.; Cousin, Agnes; Blank, Jen G.; Mangold, Nicolas; Sautter, Violaine; Maurice, Sylvestre; Clegg, Samuel M.; Gasnault, Olivier; Forni, Olivier; TOKAR, Robert; Lewin, Eric; Dyar, M. Darby

    2014-01-01

    The ChemCam instrument package on the Mars rover, Curiosity, provides new capabilities to probe the abundances of certain trace elements in the rocks and soils on Mars using the laser-induced breakdown spectroscopy technique. We focus on detecting and quantifying Li, Ba, Rb, and Sr in targets analyzed during the first 100 sols, from Bradbury Landing Site to Rocknest. Univariate peak area models and multivariate partial least squares models are presented. Li, detected for the first time direct...

  8. Simulation of atmospheric N2O with GEOS-Chem and its adjoint: evaluation of observational constraints

    OpenAIRE

    K. C. Wells; Millet, D. B.; Bousserez, N.; D. K. Henze; Chaliyakunnel, S.; T. J. Griffis; Luan, Y.; Dlugokencky, E. J.; R. G. Prinn; S. O'Doherty; R. F. Weiss; G. S. Dutton; Elkins, J. W.; Krummel, P. B.; Langenfelds, R.

    2015-01-01

    We describe a new 4D-Var inversion framework for N2O based on the GEOS-Chem chemical transport model and its adjoint, and apply this framework in a series of observing system simulation experiments to assess how well N2O sources and sinks can be constrained by the current global observing network. The employed measurement ensemble includes approximately weekly and quasi-continuous N2O measurements (hourly averages used) from several long-term monitoring netw...

  9. Assimilating compact phase space retrievals of atmospheric composition with WRF-Chem/DART: a regional chemical transport/ensemble Kalman filter data assimilation system

    Science.gov (United States)

    Mizzi, Arthur P.; Arellano, Avelino F., Jr.; Edwards, David P.; Anderson, Jeffrey L.; Pfister, Gabriele G.

    2016-03-01

    This paper introduces the Weather Research and Forecasting Model with chemistry/Data Assimilation Research Testbed (WRF-Chem/DART) chemical transport forecasting/data assimilation system together with the assimilation of compact phase space retrievals of satellite-derived atmospheric composition products. WRF-Chem is a state-of-the-art chemical transport model. DART is a flexible software environment for researching ensemble data assimilation with different assimilation and forecast model options. DART's primary assimilation tool is the ensemble adjustment Kalman filter. WRF-Chem/DART is applied to the assimilation of Terra/Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO) trace gas retrieval profiles. Those CO observations are first assimilated as quasi-optimal retrievals (QORs). Our results show that assimilation of the CO retrievals (i) reduced WRF-Chem's CO bias in retrieval and state space, and (ii) improved the CO forecast skill by reducing the Root Mean Square Error (RMSE) and increasing the Coefficient of Determination (R2). Those CO forecast improvements were significant at the 95 % level. Trace gas retrieval data sets contain (i) large amounts of data with limited information content per observation, (ii) error covariance cross-correlations, and (iii) contributions from the retrieval prior profile that should be removed before assimilation. Those characteristics present challenges to the assimilation of retrievals. This paper addresses those challenges by introducing the assimilation of compact phase space retrievals (CPSRs). CPSRs are obtained by preprocessing retrieval data sets with an algorithm that (i) compresses the retrieval data, (ii) diagonalizes the error covariance, and (iii) removes the retrieval prior profile contribution. Most modern ensemble assimilation algorithms can efficiently assimilate CPSRs. Our results show that assimilation of MOPITT CO CPSRs reduced the number of observations (and assimilation computation

  10. PREP-CHEM-SRC – 1.0: a preprocessor of trace gas and aerosol emission fields for regional and global atmospheric chemistry models

    OpenAIRE

    Freitas, S. R.; Longo, K. M.; Alonso, M. F.; M. Pirre; Marecal, V.; Grell, G; R. Stockler; R. F. Mello; Sánchez Gácita, M.

    2011-01-01

    The preprocessor PREP-CHEM-SRC presented in the paper is a comprehensive tool aiming at preparing emission fields of trace gases and aerosols for use in atmospheric-chemistry transport models. The considered emissions are from the most recent databases of urban/industrial, biogenic, biomass burning, volcanic, biofuel use and burning from agricultural waste sources. For biomass burning, emissions can be also estimated directly from satellite fire detections using a fire emission model included...

  11. Elucidating the Structure of Sugars: MW Spectroscopy Combined with Ultrafast UV Laser Vaporization

    Science.gov (United States)

    Cocinero, Emilio J.; Ecija, Patricia; Basterretxea, Francisco J.; Fernandez, Jose A.; Castano, Fernando; Lesarri, Alberto; Grabow, Jens-Uwe; Cimas, Alvaro

    2013-06-01

    Carbohydrates are one of the most versatile biochemicalbuilding blocks, widely acting in energetic, structural or recognition processes. Even the small monosaccharides display unique structural and conformational freedom and may coexist in many open-chain or cyclic forms. We recently initiated the investigation of a series of monosaccharides using a combination of ultrafast laser vaporization and microwave spectroscopy in supersonic jet expansions. We present several structural studies on carbohydrates of aldoses and ketoses of five and six carbon sugars vaporized by UV ultrafast laser vaporization and stabilized in a jet expansion. The experimental evidence confirms that sugars exhibits a α-/β-pyranose conformation (6-membered ring), sharply contrasting with the furanose form (5-membered ring) found in the nature (as component of RNA, sucrose). In addition, thanks to the use of enriched samples, we have experimentally determined the substitution and effective structures. Finally, the structure of several monosaccharides was compared and common structural patterns of their conformational landscape will be showed. E. J. Cocinero, A. Lesarri, P. écija, F. J. Basterretxea, J. U. Grabow, J. A. Fernández and F. Castaño Angew. Chem. Int. Ed. 51, 3119-3124, 2012. E. J. Cocinero, A. Lesarri, P. écija, Á. Cimas, B. G. Davis, F. J. Basterretxea, J. A. Fernández and F. Castaño J. Am. Chem. Soc. 135, 2845-2852, 2013.

  12. Structure determination of ultra dense magnesium borohydride: A first-principles study

    Science.gov (United States)

    Fan, Jing; Duan, Defang; Jin, Xilian; Bao, Kuo; Liu, Bingbing; Cui, Tian

    2013-06-01

    Magnesium borohydride (Mg(BH4)2) is one of the potential hydrogen storage materials. Recently, two experiments [Y. Filinchuk, B. Richter, T. R. Jensen, V. Dmitriev, D. Chernyshov, and H. Hagemann, Angew. Chem., Int. Ed. 50, 11162 (2011);, 10.1002/anie.201100675 L. George, V. Drozd, and S. K. Saxena, J. Phys. Chem. C 113, 486 (2009), 10.1021/jp807842t] found that α-Mg(BH4)2 can irreversibly be transformed to an ultra dense δ-Mg(BH4)2 under high pressure. Its volumetric hydrogen content at ambient pressure (147 g/cm3) exceeds twice of DOE's (U.S. Department of Energy) target (70 g/cm3) and that of α-Mg(BH4)2 (117 g/cm3) by 20%. In this study, the experimentally proposed P42nm structure of δ-phase has been found to be dynamically unstable. A new Fddd structure has been reported as a good candidate of δ-phase instead. Its enthalpy from 0 to 12 GPa is much lower than P42nm structure and the simulated X-ray diffraction spectrum is in satisfied agreement with previous experiments. In addition, the previously proposed P-3m1 structure, which is denser than Fddd, is found to be a candidate of ɛ-phase due to the agreement of Raman shifts.

  13. Determination of structure and phase transition of nanophase NH3BH3 embedded in MCM-41 mesoporous silica

    Science.gov (United States)

    Kim, Hyunjeong; Karkamkar, Abhi; Autrey, Thomas; Chupas, Peter; Proffen, Thomas

    2010-03-01

    Nanocomposition of ammonia borane (AB), NH3BH3, by loading AB in a mesoporous silica has shown great improvement in the hydrogen storage properties [1]; faster hydrogen desorption was observed at reduced temperature and the formation of borazine, by-products that affects hydrogen purity, was significantly suppressed. Even though an improvement was striking, its lack of long-range structural order and relatively light composed elements hinder conventional structural analyses. We have employed the atomic pair distribution function (PDF) analysis to investigate the nanophase AB residing in mesoporous channels of MCM-41 [2]. Temperature dependent x-ray PDF study shows that the AB confined in pores does not undergo the orthorhombic to tetragonal phase transition at 225 K that was observed in the bulk molecular crystal. Instead, it stays in the high temperature tetragonal phase over a temperature range of 110-240 K and becomes amorphous above 240 K. [1] A. Gutowska et al., Angew. Chem. Int. Ed., 44, 3578-3582 (2005). [2] H. J. Kim et al., J. Am. Chem. Soc., 131, 13749-13755 (2009).

  14. Microwave Three-Wave Mixing Experiments for Chirality Determination: Current Status

    Science.gov (United States)

    Perez, Cristobal; Shubert, V. Alvin; Schmitz, David; Medcraft, Chris; Krin, Anna; Schnell, Melanie

    2015-06-01

    Microwave three-wave mixing experiments have been shown to provide a novel and sensitive way to generate and measure enantiomer-specific molecular signatures. The handedness of the sample can be obtained from the phase of the molecular free induction decay whereas the enantiomeric excess can be determined by the amplitude of the chiral signal. After the introduction of this technique by Patterson et al. remarkable improvements have been realized and experimental strategies for both absolute phase determination and enantiomeric excess have been presented. This technique has been also successfully implemented at higher microwave frequencies. Here we present the current status of this technique as well future directions and perspectives. This will be illustrated through our systematic study of chiral terpenes as well as preliminary results in molecular clusters. Patterson, D.; Schnell, M.; Doyle, J. M. Enantiomer-Specific Detection of Chiral Molecules via Microwave Spectroscopy. Nature 2013, 497, 475-477. Patterson, D.; Doyle, J. M. Sensitive Chiral Analysis via Microwave Three-Wave Mixing. Phys. Rev. Lett. 2013, 111, 023008. Shubert, V. A.; Schmitz, D.; Patterson, D.; Doyle, J. M.; Schnell, M. Identifying Enantiomers in Mixtures of Chiral Molecules with Broadband Microwave Spectroscopy. Angew. Chem. Int. Ed. 2014, 53, 1152-1155. Lobsiger, S.; Perez, C.; Evangelisti, L.; Lehmann, K. K.; Pate, B. H. Molecular Structure and Chirality Detection by Fourier Transform Microwave Spectroscopy. J. Phys. Chem. Lett. 2014, 6, 196-200.

  15. Comparison of Mixed Layer Heights from Airborne High Spectral Resolution Lidar, Ground-based Measurements, and the WRP-Chem Model during CalNex and CARES

    Energy Technology Data Exchange (ETDEWEB)

    Scarino, Amy Jo; Obland, Michael; Fast, Jerome D.; Burton, S. P.; Ferrare, R. A.; Hostetler, Chris A.; Berg, Larry K.; Lefer, Barry; Haman, C.; Hair, John; Rogers, Ray; Butler, Carolyn; Cook, A. L.; Harper, David

    2014-06-05

    The California Research at the Nexus of Air Quality and Climate Change (CalNex) and Carbonaceous Aerosol and Radiative Effects Study (CARES) field campaigns during May and June 2010 provided a data set appropriate for studying characteristics of the planetary boundary layer (PBL). The NASA Langley Research Center (LaRC) airborne High Spectral Resolution Lidar (HSRL) was deployed to California onboard the NASA LaRC B-200 aircraft to aid incharacterizing aerosol properties during these two field campaigns. Measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm) profiles during 31 flights, many in coordination with other research aircraft and ground sites, constitute a diverse data set for use in characterizing the spatial and temporal distribution of aerosols, as well as the depth and variability of the daytime mixed layer (ML), which is a subset within the PBL. This work illustrates the temporal and spatial variability of the ML in the vicinity of Los Angeles and Sacramento, CA. ML heights derived from HSRL measurements are compared to PBL heights derived from radiosonde profiles, ML heights measured from ceilometers, and simulated PBL heights from the Weather Research and Forecasting Chemistry (WRF-Chem) community model. Comparisons between the HSRL ML heights and the radiosonde profiles in Sacramento result in a correlation coefficient value (R) of 0.93 (root7 mean-square (RMS) difference of 157 m and bias difference (HSRL radiosonde) of 5 m). HSRL ML heights compare well with those from the ceilometer in the LA Basin with an R of 0.89 (RMS difference of 108 m and bias difference (HSRL Ceilometer) of -9.7 m) for distances of up to 30 km between the B-200 flight track and the ceilometer site. Simulated PBL heights from WRF-Chem were compared with those obtained from all flights for each campaign, producing an R of 0.58 (RMS difference of 604 m and a bias difference (WRF-Chem HSRL) of -157 m) for CalNex and 0

  16. Simulation of Mexico City plumes during the MIRAGE-Mex field campaign using the WRF-Chem model

    Directory of Open Access Journals (Sweden)

    X. Tie

    2009-07-01

    Full Text Available The quantification of tropospheric O3 production in the downwind of the Mexico City plume is a major objective of the MIRAGE-Mex field campaign. We used a regional chemistry-transport model (WRF-Chem to predict the distribution of O3 and its precursors in Mexico City and the surrounding region during March 2006, and compared the model with in-situ aircraft measurements of O3, CO, VOCs, NOx, and NOy concentrations. The comparison shows that the model is capable of capturing the timing and location of the measured city plumes, and the calculated variability along the flights is generally consistent with the measured results, showing a rapid increase in O3 and its precursors when city plumes are detected. However, there are some notable differences between the calculated and measured values, suggesting that, during transport from the surface of the city to the outflow plume, ozone mixing ratios are underestimated by about 0–25% during different flights. The calculated O3-NOx, O3-CO, and O3-NOz correlations generally agree with the measured values, and the analyses of these correlations suggest that photochemical O3 production continues in the plume downwind of the city (aged plume, adding to the O3 already produced in the city and exported with the plume. The model is also used to quantify the contributions to OH reactivity from various compounds in the aged plume. This analysis suggests that oxygenated organics (OVOCs have the highest OH reactivity and play important roles for the O3 production in the aging plume. Furthermore, O3 production per NOx molecule consumed (O3 production efficiency is more efficient in the aged plume than in the young plume near the city. The major contributor to the high O3 production efficiency in the aged plume is the

  17. Simulation of Mexico City plumes during the MIRAGE-Mex field campaign using the WRF-Chem model

    Directory of Open Access Journals (Sweden)

    X. Tie

    2009-04-01

    Full Text Available The quantification of tropospheric O3 production in the Mexico City outflow is a major objective of the MIRAGE-Mex field campaign. We used a regional chemistry-transport model (WRF-Chem to predict the distribution of O3 and its precursors in Mexico City and the surrounding region during March 2006, and compared with in-situ aircraft measurement of O3, CO, VOCs, NOx, and NOy concentrations. The comparison shows that the model is capable of capturing the timing/location of the measured city plumes, and the calculated variability along the flights is generally consistent with the measured results, showing a rapid enhancement of O3 and its precursors when city plumes are detected. However, there are some notable differences between the calculated and measured values, suggesting that, during transport from the surface of the city to the outflow plume, pollution levels are underestimated by about 0–25% during different flights. The calculated O3-NOx, O3-CO, and O3-NOz correlations generally agree with the measured values, and the analysis of these correlations suggest that photochemical O3 production continues in the plume downwind of the city (aged plume, adding to the O3 already produced in the city and exported with the plume. The model is also used to quantify the contributions to OH reactivity from various compounds in the aged plume. This analysis suggests that oxygenated organics (OVOCs have the highest OH reactivity and play important roles for the O3 production in the aging plume. Furthermore, O3 production per NOx molecule consumed (O3 production efficiency is more efficient in the aged plume than in the young plume near the city. The major contributor to the high O3 production efficiency in the aged plume is the reaction RO2+NO. By

  18. Simulation of atmospheric N2O with GEOS-Chem and its adjoint: evaluation of observational constraints

    Directory of Open Access Journals (Sweden)

    K. C. Wells

    2015-07-01

    Full Text Available We describe a new 4D-Var inversion framework for N2O based on the GEOS-Chem chemical transport model and its adjoint, and apply this framework in a series of observing system simulation experiments to assess how well N2O sources and sinks can be constrained by the current global observing network. The employed measurement ensemble includes approximately weekly and quasi-continuous N2O measurements (hourly averages used from several long-term monitoring networks, N2O measurements collected from discrete air samples aboard a commercial aircraft (CARIBIC, and quasi-continuous measurements from an airborne pole-to-pole sampling campaign (HIPPO. For a two-year inversion, we find that the surface and HIPPO observations can accurately resolve a uniform bias in emissions during the first year; CARIBIC data provide a somewhat weaker constraint. Variable emission errors are much more difficult to resolve given the long lifetime of N2O, and major parts of the world lack significant constraints on the seasonal cycle of fluxes. Current observations can largely correct a global bias in the stratospheric sink of N2O if emissions are known, but do not provide information on the temporal and spatial distribution of the sink. However, for the more realistic scenario where source and sink are both uncertain, we find that simultaneously optimizing both would require unrealistically small errors in model transport. Regardless, a bias in the magnitude of the N2O sink would not affect the a posteriori N2O emissions for the two-year timescale used here, given realistic initial conditions, due to the timescale required for stratosphere–troposphere exchange (STE. The same does not apply to model errors in the rate of STE itself, which we show exerts a larger influence on the tropospheric burden of N2O than does the chemical loss rate over short (2O emissions. There, averaging kernels are highly smeared spatially and extend even to the midlatitudes, so that tropical

  19. Atmospheric composition in the Eastern Mediterranean: Influence of biomass burning during summertime using the WRF-Chem model

    Science.gov (United States)

    Bossioli, E.; Tombrou, M.; Kalogiros, J.; Allan, J.; Bacak, A.; Bezantakos, S.; Biskos, G.; Coe, H.; Jones, B. T.; Kouvarakis, G.; Mihalopoulos, N.; Percival, C. J.

    2016-05-01

    The composition of the atmosphere over the Aegean Sea (AS) during an 'Etesian' outbreak under the influence of biomass burning (BB) activity is investigated. Simulations with the fully coupled WRF-Chem model during the Aegean-GAME campaign (29/8-9/9/2011) are used to examine the BB effect over the region. Two distinct Etesian flow patterns characterized by different transport conditions are analysed. The influence of the off-line calculated BB emissions on the atmospheric chemical composition over the AS under these conditions is estimated. In addition, sensitivity runs are used to examine the influence of the biogenic emissions calculated on-line and the realistic representation of the stratosphere-troposphere exchange processes are investigated through the time-varying chemical boundary conditions from the MOZART global chemical transport model. The horizontal and vertical distributions of gaseous and aerosol species are simulated under long-range transport conditions and interpreted in relation to the evolution of the Planetary Boundary Layer (PBL). In the case of a weaker synoptic system (medium-range transport conditions), even a small variability of meteorological parameters in limited areas become critical for the spatial distribution of gases and aerosols. The BB activity increases O3, PM2.5 and organic matter concentrations up to 5.5 ppb, 5.8 μg m-3 and 3.3 μg m-3, respectively. The spatial extent of the simulated BB plumes is further examined by comparison with airborne measurements of hydrogen cyanide (HCN). The estimated effect of biogenic emissions on O3 and PM2.5 concentrations is either positive or negative (±6 ppb for O3 and up to ± 1 μg m-3 for PM2.5) depending on the emission algorithm employed. The realistic representation of the chemical boundary conditions reproduces an observed layer rich in O3 above 4 km, but also increases O3 concentrations inside the PBL by up to 40%.

  20. DECADE Web Portal: Integrating MaGa, EarthChem and GVP Will Further Our Knowledge on Earth Degassing

    Science.gov (United States)

    Cardellini, C.; Frigeri, A.; Lehnert, K. A.; Ash, J.; McCormick, B.; Chiodini, G.; Fischer, T. P.; Cottrell, E.

    2014-12-01

    The release of gases from the Earth's interior to the exosphere takes place in both volcanic and non-volcanic areas of the planet. Fully understanding this complex process requires the integration of geochemical, petrological and volcanological data. At present, major online data repositories relevant to studies of degassing are not linked and interoperable. We are developing interoperability between three of those, which will support more powerful synoptic studies of degassing. The three data systems that will make their data accessible via the DECADE portal are: (1) the Smithsonian Institution's Global Volcanism Program database (GVP) of volcanic activity data, (2) EarthChem databases for geochemical and geochronological data of rocks and melt inclusions, and (3) the MaGa database (Mapping Gas emissions) which contains compositional and flux data of gases released at volcanic and non-volcanic degassing sites. These databases are developed and maintained by institutions or groups of experts in a specific field, and data are archived in formats specific to these databases. In the framework of the Deep Earth Carbon Degassing (DECADE) initiative of the Deep Carbon Observatory (DCO), we are developing a web portal that will create a powerful search engine of these databases from a single entry point. The portal will return comprehensive multi-component datasets, based on the search criteria selected by the user. For example, a single geographic or temporal search will return data relating to compositions of emitted gases and erupted products, the age of the erupted products, and coincident activity at the volcano. The development of this level of capability for the DECADE Portal requires complete synergy between these databases, including availability of standard-based web services (WMS, WFS) at all data systems. Data and metadata can thus be extracted from each system without interfering with each database's local schema or being replicated to achieve integration at

  1. The effect of SRTM and Corine Land Cover data on calculated gas and PM10 concentrations in WRF-Chem

    Science.gov (United States)

    De Meij, A.; Bossioli, E.; Penard, C.; Vinuesa, J. F.; Price, I.

    2015-01-01

    The goal of this study is to investigate the impact of the high resolution Shuttle Radar Topography Mission (SRTM) 90 m × 90 m topography data, together with the 100 m × 100 m resolution Corine Land Cover 2006 on the simulated gas and particulate matter (PM10) concentrations by WRF-Chem. We focused our analysis on the well-known highly urbanized region of the Po Valley. Large differences are found in the geographical distribution of the land cover classes between Corine Land Cover and 30 arc seconds USGS. The simulation with the SRTM and Corine Land Cover increases modelled temperature at 2 m and reduces wind speeds due to more friction at the surface induced by the Corine Land Cover. Latent and sensible heat fluxes show large differences between the two simulations and the related boundary layer development and depth. The simulation with the SRTM and Corine Land Cover favours the precipitation amount over a large of part the Alps and follows the pattern of the difference in topography between the two topography data sets. In term of air quality indicators, impacts are also large and geographical dependent. Monthly average of CO, NO and SO2 concentrations over a large part of the Po Valley are higher when using Corine Land Cover, up to ∼20, ∼50 and ∼55%, respectively. With respect to PM10, the impacts are also geographical dependent. Over the Po valley area, calculated PM10 concentrations are in general higher using Corine Land Cover (up to 6.7 ug/m3 [∼26%] westerly of Milan) while differences are smaller over the Alps (∼0.25ug/m3 [∼20%]). Although the scope of this work is not to evaluate the model performance in calculated meteorological parameters and gas and PM10 concentrations, calculated values by the simulation with SRTM and Corine Land Cover show a better agreement with the observations than the simulation with the USGS topography and land cover data sets. A quantitative comparison between modelled and observed monthly average PM10

  2. Coupling aerosol-cloud-radiative processes in the WRF-Chem model: investigating the radiative impact of elevated point sources

    Directory of Open Access Journals (Sweden)

    E. G. Chapman

    2008-08-01

    Full Text Available The local and regional influence of elevated point sources on summertime aerosol forcing and cloud-aerosol interactions in northeastern North America was investigated using the WRF-Chem community model. The direct effects of aerosols on incoming solar radiation were simulated using existing modules to relate aerosol sizes and chemical composition to aerosol optical properties. Indirect effects were simulated by adding a prognostic treatment of cloud droplet number and adding modules that activate aerosol particles to form cloud droplets, simulate aqueous-phase chemistry, and tie a two-moment treatment of cloud water (cloud water mass and cloud droplet number to an existing radiation scheme. Fully interactive feedbacks thus were created within the modified model, with aerosols affecting cloud droplet number and cloud radiative properties, and clouds altering aerosol size and composition via aqueous processes, wet scavenging, and gas-phase-related photolytic processes. Comparisons of a baseline simulation with observations show that the model captured the general temporal cycle of aerosol optical depths (AODs and produced clouds of comparable thickness to observations at approximately the proper times and places. The model overpredicted SO2 mixing ratios and PM2.5 mass, but reproduced the range of observed SO2 to sulfate aerosol ratios, suggesting that atmospheric oxidation processes leading to aerosol sulfate formation are captured in the model. The baseline simulation was compared to a sensitivity simulation in which all emissions at model levels above the surface layer were set to zero, thus removing stack emissions. Instantaneous, site-specific differences for aerosol and cloud related properties between the two simulations could be quite large, as removing above-surface emission sources influenced when and where clouds formed within the modeling domain. When summed spatially over the finest resolution model

  3. Constraints on ship NOx emissions in Europe using GEOS-Chem and OMI satellite NO2 observations

    Directory of Open Access Journals (Sweden)

    G. C. M. Vinken

    2013-07-01

    Full Text Available We present a top-down ship NOx emission inventory for the Baltic Sea, North Sea, Bay of Biscay and Mediterranean Sea, based on satellite observed tropospheric NO2 columns of the Ozone Monitoring Instrument (OMI for 2005–2006. We improved the representation of ship emissions in the GEOS-Chem chemistry transport model, and compared simulated NO2 columns to consistent satellite observations. Relative differences between simulated and observed NO2 columns have been used to constrain ship emissions in four European seas (Baltic Sea, North Sea, Bay of Biscay and Mediterranean Sea. The constrained ship tracks account for 39% of total top-down European ship NOx emissions, which amounts to 0.96 Tg N for 2005, and 1.0 Tg N for 2006 (11–15% lower than the bottom-up EMEP ship emission inventory. Our results indicate that EMEP emissions in the Mediterranean Sea are too high (by 60% and misplaced by up to 150 km, which can have important consequences for local air quality simulations. In the North Sea, our top-down emissions amount to 0.05 Tg N for 2005 (35% lower than EMEP. Increased top-down emissions were found for the Baltic Sea and Bay of Biscay, with emission totals of 0.05 Tg N (131% higher than EMEP and 0.08 Tg N for 2005 (128% higher than EMEP, respectively. Our study explicitly accounts for the (non-linear sensitivity of satellite retrievals to changes in the a priori NO2 profiles. Although the effect of this sensitivity might be minor for small emission increments, our findings stress the need for consistent information in satellite retrieval and model, as satellite observations are never fully independent of model information (i.e. assumptions on vertical NO2 profiles. Our study provides for the first time a space-based top-down ship NOx emission inventory, and can serve as a framework for future studies to constrain ship emissions using satellite NO2 observations in other seas.

  4. The Int7G24A variant of transforming growth factor-beta receptor type I is a risk factor for colorectal cancer in the male Spanish population: a case-control study

    International Nuclear Information System (INIS)

    The Int7G24A variant of transforming growth factor-beta receptor type I (TGFBR1) has been shown to increase the risk for kidney, ovarian, bladder, lung and breast cancers. Its role in colorectal cancer (CRC) has not been established. The aims of this study were to assess the association of TGFBR1*Int7G24A variant with CRC occurrence, patient age, gender, tumour location and stage. We performed a case-control study with 504 cases of sporadic CRC; and 504 non-cancerous age, gender and ethnically matched controls. Genotyping analysis was performed using allelic discrimination assay by real time PCR. The Int7G24A variant was associated with increased CRC incidence in an additive model of inheritance (P for trend = 0.005). No significant differences were found between Int7G24A genotypes and tumour location or stage. Interestingly, the association of the Int7G24A variant with CRC risk was significant in men (odds ratio 4.10 with 95% confidence intervals 1.41-11.85 for homozygous individuals; P for trend = 0.00023), but not in women. We also observed an increase in susceptibility to CRC for individuals aged less than 70 years. Our data suggest that the Int7G24A variant represents a risk factor for CRC in the male Spanish population

  5. Comments on: "Starting solutions for some unsteady unidirectional flows of a second grade fluid," [Int. J. Eng. Sci. 43 (2005) 781

    CERN Document Server

    Christov, Ivan C

    2011-01-01

    A significant mathematical error is identified and corrected in a recent highly-cited paper on oscillatory flows of second-grade fluids [Fetecau & Fetecau (2005). Int. J. Eng. Sci., 43, 781--789]. The corrected solutions are shown to agree identically with numerical ones generated by a finite-difference scheme, while the original ones of Fetecau & Fetecau do not. A list of other recent papers in the literature that commit the error corrected in this Comment is compiled. Finally, a summary of related erroneous papers in this journal is presented as an Appendix.

  6. LabVIEW intègre et accélère les processus de développement en physique expérimentale

    OpenAIRE

    Zimmermann, O.; P. Stassi

    2003-01-01

    La physique expérimentale a massivement recours à la programmation d'instruments. Nous présentons deux réalisations LabVIEW du LPSC, pour les expériences GRAAL et PLANCK. En nous appuyant sur ces exemples nous dégagerons certaines qualités qui permetent à LabVIEW d'intégrer l'environnement et les méthodes de la recherche. Enfin nous examinerons des points de concordance profonds entre la technologie LabVIEW et les contraintes techniques de la programmation des expériences.

  7. MIAE : collection de référence dédiée aux microorganismes d’intérêt agro-environnemental

    OpenAIRE

    Héraud, Cécile; Steinberg, Christian; Corberand, Thérèse; Gautheron, Nadine; Revellin, Cécile; Edel-Hermann, Veronique; Lemanceau, Philippe

    2010-01-01

    La collection de Microorganismes d’Intérêt Agro-Environnemental (MIAE), centre INRA de Dijon, possède actuellement 15 000 souches d'origine tellurique microbiennes qu'il est indispensable de préserver et de gérer au mieux. Ce sont : - des bactéries impliquées dans i) la nutrition azotée des plantes (parmi lesquelles 4 500 Rhizobium, ii) la croissance et la santé des plantes (dont 3 000 Pseudomonas ), iii) la dépollution de l'environnement sol, eau, ou atmosphère, et des bactéries apparten...

  8. Instituições e cooperação social em Douglass North e nos intérpretes weberianos do atraso brasileiro

    Directory of Open Access Journals (Sweden)

    Hélio Afonso de Aguilar Filho

    2011-09-01

    Full Text Available O artigo tem por objetivo resgatar a aproximação teórica entre o arcabouço institucionalista de Douglass North e os argumentos utilizados por intérpretes do Brasil de reconhecida orientação weberiana, como Sérgio Buarque de Holanda, Vianna Moog e Raymundo Faoro. Para tanto, privilegia o entendimento da relação entre instituições e cooperação social presentes na obra desses autores como variável relevante para explicar o desempenho de longo prazo da economia brasileira, bem como de seu relativo atraso.

  9. The Odda System: Integration of Conventional Programming and Artificial Intelligence Le système ODDA : intégration de programmation classique et d'intelligence artificielle

    Directory of Open Access Journals (Sweden)

    Cayeux E.

    2006-11-01

    Full Text Available The ODDA system (Offshore Directional Drilling Advisor is an example of how numerical packages, a relational database, graphical interfaces and knowledge bases can be integrated into an industrial application. Le système ODDA (Offshore Directional Drilling Advisor est un exemple illustrant la façon dont des progiciels numériques, une base de données relationnelle, des interfaces graphiques et des bases de connaissances peuvent être intégrés dans une application industrielle.

  10. Etude et mise au point de composants magnétiques multicouches pour intégration en électronique de puissance

    OpenAIRE

    Brun, Edouard,

    2014-01-01

    Ces dernières années, les besoins en électronique de puissance s’orientent vers la miniaturisation globale des cartes électroniques, parallèlement à une augmentation des puissances de travail. C’est dans ce contexte que s’inscrivent les travaux de cette thèse, principalement axée sur l’élaboration, l’amélioration des performances et l’intégration de composants passifs (inductances, transformateurs…) en électronique de puissance.Les matériaux choisis pour remplir les fonctions magnétiques de c...

  11. Vers des centrales inertielles compactes basées sur des nanojauges piezorésistives : problématique de co-intégration

    OpenAIRE

    Deimerly, Yannick

    2013-01-01

    This thesis was carried out in an industrial context of strong competition in connection with miniature silicon sensors for the huge so-called “consumer” market, where the “Smartphone” is the killer application; its increasing functionality creates a need for the so-called ‘10-axis' inertial multi-sensors (3-axis accelerometer, 3-axis magnetometer, 3-axis gyro sensor and pressure). Similarly to integrated circuits, cost constraints on such sensors translate into a requirement in terms of inte...

  12. Comparaison de populations de carpe commune (Cyprinus carpio à taille commerciale : intérêt d'une approche globale

    Directory of Open Access Journals (Sweden)

    PEREIRA V.

    1999-07-01

    Une discrimination géographique des populations est possible mais elle repose sur une approche globale intégrant l'ensemble des paramètres. Les différences semblent essentiellement liées aux conditions environnementales et permettent de distinguer les lots issus des régions où l'élevage est plus intensif et traditionnellement centré sur la carpe (Dombes, Forez, Lorraine et les lots correspondant à un élevage plus extensif et davantage orienté vers le marché du repeuplement (Allier, Brenne, Poitou-Charentes.

  13. Intégration des TIC par les enseignants : premiers résultats d’une enquête suisse

    Directory of Open Access Journals (Sweden)

    Abdeljalil Akkari

    2006-01-01

    Full Text Available [Français] Cet article propose tout d’abord un état de la littérature scientifique dans les domaines de l’intégration et de la formation aux TIC dans la pratique enseignante. Dans une deuxième partie sont présentés les premiers résultats d’une enquête menée sur l’intégration des TIC dans le système scolaire du canton du Jura en Suisse. L’article se termine par la présentation des premières conclusions de cette recherche et une discussion sur les opportunités pédagogiques qu’ouvrent les TIC pour les enseignants débutants. [English] In the first part, this paper summarizes the existing scientific literature on the use of information and communication technologies (ICT by teachers. In the second part, results of data analysis from a regional survey of the Swiss educational ICT infrastructure and its use in schools are presented. In the third part, we discuss the opportunity for beginning teachers to transform their pedagogical practices with the increasing availability of ICT in school.

  14. Validating the WRF-Chem model for wind energy applications using High Resolution Doppler Lidar data from a Utah 2012 field campaign

    Science.gov (United States)

    Mitchell, M. J.; Pichugina, Y. L.; Banta, R. M.

    2015-12-01

    Models are important tools for assessing potential of wind energy sites, but the accuracy of these projections has not been properly validated. In this study, High Resolution Doppler Lidar (HRDL) data obtained with high temporal and spatial resolution at heights of modern turbine rotors were compared to output from the WRF-chem model in order to help improve the performance of the model in producing accurate wind forecasts for the industry. HRDL data were collected from January 23-March 1, 2012 during the Uintah Basin Winter Ozone Study (UBWOS) field campaign. A model validation method was based on the qualitative comparison of the wind field images, time-series analysis and statistical analysis of the observed and modeled wind speed and direction, both for case studies and for the whole experiment. To compare the WRF-chem model output to the HRDL observations, the model heights and forecast times were interpolated to match the observed times and heights. Then, time-height cross-sections of the HRDL and WRF-Chem wind speed and directions were plotted to select case studies. Cross-sections of the differences between the observed and forecasted wind speed and directions were also plotted to visually analyze the model performance in different wind flow conditions. A statistical analysis includes the calculation of vertical profiles and time series of bias, correlation coefficient, root mean squared error, and coefficient of determination between two datasets. The results from this analysis reveals where and when the model typically struggles in forecasting winds at heights of modern turbine rotors so that in the future the model can be improved for the industry.

  15. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    Science.gov (United States)

    Wiens, R. C.; Maurice, S.; Lasue, J.; Forni, O.; Anderson, R. B.; Clegg, S.; Bender, S.; Blaney, D.; Barraclough, B. L.; Cousin, A.; Deflores, L.; Delapp, D.; Dyar, M. D.; Fabre, C.; Gasnault, O.; Lanza, N.; Mazoyer, J.; Melikechi, N.; Meslin, P.-Y.; Newsom, H.; Ollila, A.; Perez, R.; Tokar, R. L.; Vaniman, D.

    2013-04-01

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350-550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  16. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    Science.gov (United States)

    Wiens, R.C.; Maurice, S.; Lasue, J.; Forni, O.; Anderson, R.B.; Clegg, S.; Bender, S.; Blaney, D.; Barraclough, B.L.; Cousin, A.; DeFlores, L.; Delapp, D.; Dyar, M.D.; Fabre, C.; Gasnault, O.; Lanza, N.; Mazoyer, J.; Melikechi, N.; Meslin, P.-Y.; Newsom, H.; Ollila, A.; Perez, R.; Tokar, R.; Vaniman, D.

    2013-01-01

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350–550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  17. WRF-Chem simulations of a typical pre-monsoon dust storm in northern India: influences on aerosol optical properties and radiation budget

    Directory of Open Access Journals (Sweden)

    R. Kumar

    2013-08-01

    Full Text Available The impact of a typical pre-monsoon season (April–June dust storm event on the regional aerosol optical properties and radiation budget in northern India is analyzed. The dust storm event lasted from 17 to 22 April 2010 and the WRF-Chem model estimated total dust emissions of 7.5 Tg over the model domain. Both in situ (AERONET and satellite observations show significant increase (>50% in local to regional scale aerosol optical depth (AOD and decrease (>70% in the Angström exponent (α during this period. Amongst the AERONET sites in this region, Kanpur was influenced the most where the AOD reached up to 2.1 and the α decreased to −0.09 during the dust storm period. The WRF-Chem model reproduced the spatial and temporal distributions of dust plumes and aerosol optical properties but generally underestimated the AOD. The average MODIS and WRF-Chem AOD (550 nm values in high dust laden region are estimated as 0.80 ± 0.30 and 0.68 ± 0.28, respectively. Model results show that dust particles cool the surface and the top of the atmosphere, and warm the atmosphere. The regionally averaged radiative perturbation due to dust aerosols is estimated as −2.0 ± 3.0 W m−2 at the top of the atmosphere, 2.3 ± 1.8 W m−2 in the atmosphere and −4.4 ± 3.1 W m−2 at the surface. The impact of these radiative perturbations on the surface energy budget is estimated to be small on a regional scale but significant locally.

  18. Evaluating the skill of high-resolution WRF-Chem simulations in describing drivers of aerosol direct climate forcing on the regional scale

    Science.gov (United States)

    Crippa, P.; Sullivan, R. C.; Thota, A.; Pryor, S. C.

    2016-01-01

    Assessing the ability of global and regional models to describe aerosol optical properties is essential to reducing uncertainty in aerosol direct radiative forcing in the contemporary climate and to improving confidence in future projections. Here we evaluate the performance of high-resolution simulations conducted using the Weather Research and Forecasting model with coupled with Chemistry (WRF-Chem) in capturing spatiotemporal variability of aerosol optical depth (AOD) and the Ångström exponent (AE) by comparison with ground- and space-based remotely sensed observations. WRF-Chem is run over eastern North America at a resolution of 12 km for a representative year (2008). A systematic positive bias in simulated AOD relative to observations is found (annual mean fractional bias (MFB) is 0.15 and 0.50 relative to MODIS (MODerate resolution Imaging Spectroradiometer) and AERONET, respectively), whereas the spatial variability is well captured during most months. The spatial correlation of observed and simulated AOD shows a clear seasonal cycle with highest correlation during summer months (r = 0.5-0.7) when the aerosol loading is large and more observations are available. The model is biased towards the simulation of coarse-mode aerosols (annual MFB for AE = -0.10 relative to MODIS and -0.59 for AERONET), but the spatial correlation for AE with observations is 0.3-0.5 during most months, despite the fact that AE is retrieved with higher uncertainty from the remote-sensing observations. WRF-Chem also exhibits high skill in identifying areas of extreme and non-extreme aerosol loading, and its ability to correctly simulate the location and relative intensity of extreme aerosol events (i.e., AOD > 75th percentile) varies between 30 and 70 % during winter and summer months, respectively.

  19. Comment on “Frequency-domain stimulated and spontaneous light emission signals at molecular junctions” [J. Chem. Phys. 141, 074107 (2014)

    International Nuclear Information System (INIS)

    We discuss the derivation of the optical response in molecular junctions presented by U. Harbola et al. [J. Chem. Phys. 141, 074107 (2014)], which questions some terms in the theory of Raman scattering in molecular junctions developed in our earlier publications. We show that the terms considered in our theory represent the correct contribution to calculated Raman scattering and are in fact identical to those considered by Harbola et al. We also indicate drawbacks of the presented approach in treating the quantum transport part of the problem

  20. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    International Nuclear Information System (INIS)

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350–550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  1. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    Energy Technology Data Exchange (ETDEWEB)

    Wiens, R.C., E-mail: rwiens@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Maurice, S.; Lasue, J.; Forni, O. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Anderson, R.B. [United States Geological Survey, Flagstaff, AZ (United States); Clegg, S. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Bender, S. [Planetary Science Institute, Tucson, AZ (United States); Blaney, D. [Jet Propulsion Laboratory, Pasadena, CA (United States); Barraclough, B.L. [Planetary Science Institute, Tucson, AZ (United States); Cousin, A. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Deflores, L. [Jet Propulsion Laboratory, Pasadena, CA (United States); Delapp, D. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Dyar, M.D. [Mount Holyoke College, South Hadley, MA (United States); Fabre, C. [Georessources, Nancy (France); Gasnault, O. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Lanza, N. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Mazoyer, J. [LESIA, Observatoire de Paris, Meudon (France); Melikechi, N. [Delaware State University, Dover, DE (United States); Meslin, P.-Y. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Newsom, H. [University of New Mexico, Albuquerque, NM (United States); and others

    2013-04-01

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350–550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  2. Simulation of atmospheric N2O with GEOS-Chem and its adjoint: evaluation of observational constraints

    OpenAIRE

    K. C. Wells; Millet, D. B.; Bousserez, N.; D. K. Henze; Chaliyakunnel, S.; T. J. Griffis; Luan, Y.; Dlugokencky, E. J.; R. G. Prinn; S. O'Doherty; R. F. Weiss; G. S. Dutton; Elkins, J. W.; Krummel, P. B.; Langenfelds, R.

    2015-01-01

    We describe a new 4D-Var inversion framework for nitrous oxide (N2O) based on the GEOS-Chem chemical transport model and its adjoint, and apply it in a series of observing system simulation experiments to assess how well N2O sources and sinks can be constrained by the current global observing network. The employed measurement ensemble includes approximately weekly and quasi-continuous N2O measurements (hourly averages used) from several long-term monitoring networks, N2O mea...

  3. University-School Partnerships: on the impact on students of Summer Schools (for school students aged 17-18) run by Bristol ChemLabS

    OpenAIRE

    Grayson, David

    2010-01-01

    PUBLISHED Chemistry summer schools for 17-18 year old school students in the UK were run by Bristol ChemLabS, a Centre for Excellence in Teaching and Learning in Chemistry at the University of Bristol. Students attending were all studying Chemistry at post-16 level (A level in the UK) and experienced not only new practical techniques but also lectures on cutting-edge science as well as interacting with postgraduate role models. The students completed pre and post summer scho...

  4. Sources, seasonality, and trends of Southeast US aerosol: an integrated analysis of surface, aircraft, and satellite observations with the GEOS-Chem chemical transport model

    Directory of Open Access Journals (Sweden)

    P. S. Kim

    2015-07-01

    Full Text Available We use an ensemble of surface (EPA CSN, IMPROVE, SEARCH, AERONET, aircraft (SEAC4RS, and satellite (MODIS, MISR observations over the Southeast US during the summer-fall of 2013 to better understand aerosol sources in the region and the relationship between surface particulate matter (PM and aerosol optical depth (AOD. The GEOS-Chem global chemical transport model (CTM with 25 km × 25 km resolution over North America is used as a common platform to interpret measurements of different aerosol variables made at different times and locations. Sulfate and organic aerosol (OA are the main contributors to surface PM2.5 (mass concentration of PM finer than 2.5 μm aerodynamic diameter and AOD over the Southeast US. GEOS-Chem simulation of sulfate requires a missing oxidant, taken here to be stabilized Criegee intermediates, but which could alternatively reflect an unaccounted for heterogeneous process. Biogenic isoprene and monoterpenes account for 60 % of OA, anthropogenic sources for 30 %, and open fires for 10 %. 60 % of total aerosol mass is in the mixed layer below 1.5 km, 20 % in the cloud convective layer at 1.5–3 km, and 20 % in the free troposphere above 3 km. This vertical profile is well captured by GEOS-Chem, arguing against a high-altitude source of OA. The extent of sulfate neutralization (f = [NH4+]/(2[SO42−] + [NO3−] is only 0.5–0.7 mol mol−1 in the observations, despite an excess of ammonia present, which could reflect suppression of ammonia uptake by organic aerosol. This would explain the long-term decline of ammonium aerosol in the Southeast US, paralleling that of sulfate. The vertical profile of aerosol extinction over the Southeast US follows closely that of aerosol mass. GEOS-Chem reproduces observed total column aerosol mass over the Southeast US within 6 %, column aerosol extinction within 16 %, and space-based AOD within 21 %. The large AOD decline observed from summer to winter is driven by sharp declines in both

  5. pH and temperature dual-sensitive liposome gel based on novel cleavable mPEG-Hz-CHEMS polymeric vaginal delivery system

    Directory of Open Access Journals (Sweden)

    Chen D

    2012-05-01

    Full Text Available Daquan Chen,1,2 Kaoxiang Sun,1,2 Hongjie Mu,1 Mingtan Tang,3 Rongcai Liang,1,2 Aiping Wang,1,2 Shasha Zhou,1 Haijun Sun,1 Feng Zhao,1 Jianwen Yao,1 Wanhui Liu1,21School of Pharmacy, Yantai University, 2State Key Laboratory of Longacting and Targeting Drug Delivery Systems, Yantai, 3School of Pharmaceutical Sciences, Shandong University, Jinan, People's Republic of ChinaBackground: In this study, a pH and temperature dual-sensitive liposome gel based on a novel cleavable hydrazone-based pH-sensitive methoxy polyethylene glycol 2000-hydrazone-cholesteryl hemisuccinate (mPEG-Hz-CHEMS polymer was used for vaginal administration.Methods: The pH-sensitive, cleavable mPEG-Hz-CHEMS was designed as a modified pH-sensitive liposome that would selectively degrade under locally acidic vaginal conditions. The novel pH-sensitive liposome was engineered to form a thermogel at body temperature and to degrade in an acidic environment.Results: A dual-sensitive liposome gel with a high encapsulation efficiency of arctigenin was formed and improved the solubility of arctigenin characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry. The dual-sensitive liposome gel with a sol-gel transition at body temperature was degraded in a pH-dependent manner, and was stable for a long period of time at neutral and basic pH, but cleavable under acidic conditions (pH 5.0. Arctigenin encapsulated in a dual-sensitive liposome gel was more stable and less toxic than arctigenin loaded into pH-sensitive liposomes. In vitro drug release results indicated that dual-sensitive liposome gels showed constant release of arctigenin over 3 days, but showed sustained release of arctigenin in buffers at pH 7.4 and pH 9.0.Conclusion: This research has shed some light on a pH and temperature dual-sensitive liposome gel using a cleavable mPEG-Hz-CHEMS polymer for vaginal delivery.Keywords: mPEG-Hz-CHEMS polymer, pH-sensitive liposomes, thermosensitive

  6. Impacts of air-sea interactions on regional air quality predictions using WRF/Chem v3.6.1 coupled with ROMS v3.7: southeastern US example

    Science.gov (United States)

    He, J.; He, R.; Zhang, Y.

    2015-11-01

    Air-sea interactions have significant impacts on coastal convection and surface fluxes exchange, which are important for the spatial and vertical distributions of air pollutants that affect public health, particularly in densely populated coastal areas. To understand the impacts of air-sea interactions on coastal air quality predictions, sensitivity simulations with different cumulus parameterization schemes and atmosphere-ocean coupling are conducted in this work over southeastern US in July 2010 using the Weather Research and Forecasting Model with Chemistry (WRF/Chem). The results show that different cumulus parameterization schemes can result in an 85 m difference in the domain averaged planetary boundary layer height (PBLH), and 4.8 mm difference in the domain averaged daily precipitation. Comparing to WRF/Chem without air-sea interactions, WRF/Chem with a 1-D ocean mixed layer model (WRF/Chem-OML) and WRF/Chem coupled with a 3-D Regional Ocean Modeling System (WRF/Chem-ROMS) predict the domain averaged changes in the sea surface temperature of 0.1 and 1.0 °C, respectively. The simulated differences in the surface concentrations of ozone (O3) and PM2.5 between WRF/Chem-ROMS and WRF/Chem can be as large as 17.3 ppb and 7.9 μg m-3, respectively. The largest changes simulated from WRF/Chem-ROMS in surface concentrations of O3 and particulate matter with diameter less than and equal to 2.5 μm (PM2.5) occur not only along coast and remote ocean, but also over some inland areas. Extensive validations against observations, show that WRF/Chem-ROMS improves the predictions of most cloud and radiative variables, and surface concentrations of some chemical species such as sulfur dioxide, nitric acid, maximum 1 h and 8 h O3, sulfate, ammonium, nitrate, and particulate matter with diameter less than and equal to 10 μm (PM10). This illustrates the benefits and needs of using coupled atmospheric-ocean model with advanced model representations of air-sea interactions for

  7. Reduction and scientific analysis of data from the charge-energy-mass (CHEM) spectrometer on the AMPTE/CCE spacecraft. Cumulative Semiannual progress report, August 1984-August 1987

    International Nuclear Information System (INIS)

    The Charge-Energy-Mass (CHEM) spectrometer instrument on the AMPTE/Charge Composition Explorer (CCE) spacecraft is designed to measure the mass and charge-state abundance of magnetospheric and magnetosheath ions between 0.3 and 315 keV/e, an energy range that includes the bulk of the ring current and the dynamically important portion of the plasma sheet population. Continuing research is being conducted using the AMPTE mission data set, and in particular, that of the CHEM spectrometer which has operated flawlessly since launch and still provides excellent quality data. The requirted routine data processing and reduction, and software develpment continues to be performed. Scientific analysis of composition data in a number of magnetospheric regions including the ring current region, near-earth plasma sheet and subsolar magnetosheath continues to be undertaken. Correlative studies using data from the sister instrument SULEICA, which determines the mass and charge states of ions in the energy range of approximately 10 to 250 keV/e on the IRM, as well as other data from the CCE and IRM spacecraft, particularly in the upstream region and plasma sheet have also been undertaken

  8. Application of WRF/Chem-MADRID and WRF/Polyphemus in Europe – Part 2: Evaluation of chemical concentrations, sensitivity simulations, and aerosol-meteorology interactions

    Directory of Open Access Journals (Sweden)

    C. Seigneur

    2013-02-01

    Full Text Available An offline-coupled model (WRF/Polyphemus and an online-coupled model (WRF/Chem-MADRID are applied to simulate air quality in July 2001 at horizontal grid resolutions of 0.5° and 0.125° over western Europe. The model performance is evaluated against available surface and satellite observations. The two models simulate different concentrations in terms of domainwide performance statistics, spatial distribution, temporal variations, and column abundance. WRF/Chem-MADRID at 0.5° gives higher values than WRF/Polyphemus for the domainwide mean and over polluted regions in central and southern Europe for all surface concentrations and column variables except for TOR. Compared with observations, WRF/Polyphemus gives better statistical performance for daily HNO3, SO2, and NO2 at the EMEP sites, max 1-h O3 at the AirBase sites, PM2.5 at the AirBase sites, max 8-h O3 and PM10 composition at all sites, column abundance of CO, NO2, TOR, and AOD, whereas WRF/Chem-MADRID gives better statistical performance for NH3, hourly SO2, NO2, and O3 at the AirBase and BDQA sites, max 1-h O3 at the BDQA and EMEP sites, and PM10 at all sites. WRF/Chem-MADRID generally reproduces well the observed high hourly concentrations of SO2 and NO2 at most sites except for extremely high episodes at a few sites, and WRF/Polyphemus performs well for hourly SO2 concentrations at most rural or background sites where pollutant levels are relatively low, but it underpredicts the observed hourly NO2 concentrations at most sites. Both models generally capture well the daytime max 8-h O3 concentrations and diurnal variations of O3 with more accurate peak daytime and minimal nighttime values by WRF/Chem-MADRID, but neither models reproduce extremely low nighttime O3 concentrations at several urban and suburban sites due to underpredictions of NOx and thus insufficient titration of O3 at night. WRF/Polyphemus gives more accurate concentrations of PM2.5, and WRF/Chem-MADRID reproduces

  9. Impact of chemical and meteorological boundary and initial conditions on air quality modeling: WRF-Chem sensitivity evaluation for a European domain

    Science.gov (United States)

    Ritter, Mathias; Müller, Mathias D.; Jorba, Oriol; Parlow, Eberhard; Liu, L.-J. Sally

    2013-01-01

    This study evaluates the impact of different chemical and meteorological boundary and initial conditions on the state-of-the-art Weather Research and Forecasting (WRF) model with its chemistry extension (WRF-Chem). The evaluation is done for July 2005 with 50 km horizontal resolution. The effect of monthly mean chemical boundary conditions derived from the chemical transport model LMDZ-INCA on WRF-Chem is evaluated against the effect of the preset idealized profiles. Likewise, the impact of different meteorological initial and boundary conditions (GFS and Reanalysis II) on the model is evaluated. Pearson correlation coefficient between these different runs range from 0.96 to 1.00. Exceptions exists for chemical boundary conditions on ozone and for meteorological boundary conditions on PM10, where coefficients of 0.90 were obtained. Best results were achieved with boundary and initial conditions from LMDZ-INCA and GFS. Overall, the European simulations show encouraging results for observed air pollutant, with ozone being the most and PM10 being the least satisfying.

  10. Chem TV: Choices I, v. 1.5.1 (by B. A. Luceigh, P. Ngo, and J. Chen)

    Science.gov (United States)

    Kraig Steffen, L.

    1999-08-01

    CHEM TV: Sunland, CA, 1998. 24.95, students; 59.95, faculty. This CD-ROM presents a series of interactive overviews and drills for students of organic chemistry. The material covered is generally taught in the first semester. This suite is much more than a simple presentation of material and, for students sufficiently motivated to take the time and work with the problems, will provide valuable review. Five interactive spaces are provided: concentration drills that emphasize recall of related structures/names, reagents/reactions, and stereochemistry; a structural review based on epinephrine; interactive synthesis projects; arcade game reagent review; and a set of timed self-tests. The CD-ROM installed and ran without problem on a Power PC Mac and on a Pentium running Windows 95. The program did fail to run when a student reviewing it switched to a very new version of Windows Quick Time. Most of the drills ran without a problem, although at times it was unclear how to respond to queries. I turned off the music, which would be much less annoying if the loops were simply longer. Publishers are flooding the market with add-on computer-based materials for the various levels of chemistry. Many constitute little more than a stack of overheads. This is one that may be of sufficient value to warrant the extra cost. A large number of examples are provided for many of the areas covered. Most of the graphical interfaces are clear and easy to manipulate, with the exception of a couple of mechanistic screens that had hard-to-figure-out arrows. Two sections, or modules, are of special note. The first of these is the synthesis challenges, where students must choose reactants, reagents, and reaction conditions for a particular reaction. These synthesis problems are well thought out and can be challenging. It is unfortunate that there are only five of them. The Self-Tests module is also of great practical value, forcing students to work through a variety of topics (200 problems) with

  11. Development of a source oriented version of the WRF/Chem model and its application to the California Regional PM10/PM2.5 Air Quality Study

    Directory of Open Access Journals (Sweden)

    H. Zhang

    2013-06-01

    Full Text Available A source-oriented representation of airborne particulate matter was added to the Weather Research & Forecasting (WRF model with chemistry (WRF/Chem. The source-oriented aerosol separately tracks primary particles with different hygroscopic properties rather than instantaneously combining them into an internal mixture. The source-oriented approach avoids artificially mixing light absorbing black + brown carbon particles with materials such as sulfate that would encourage the formation of additional coatings. Source-oriented particles undergo coagulation and gas-particle conversion, but these processes are considered in a dynamic framework that realistically "ages" primary particles over hours and days in the atmosphere. The source-oriented WRF/Chem model more accurately predicts radiative feedbacks from anthropogenic aerosols compared to models that make internal mixing or other artificial mixing assumptions. A three-week stagnation episode (15 December 2000 to 6 January 2001 during the California Regional PM10/PM2.5 Air Quality Study (CRPAQS was chosen for the initial application of the new modeling system. Emissions were obtained from the California Air Resources Board. Gas-phase reactions were modeled with the SAPRC90 photochemical mechanism. Gas-particle conversion was modeled as a dynamic process with semi-volatile vapor pressures at the particle surface calculated using ISORROPIA. Source oriented calculations were performed for 8 particle size fractions ranging from 0.01–10 μm particle diameters with a spatial resolution of 4 km and hourly time resolution. Primary particles emitted from diesel engines, wood smoke, high sulfur fuel combustion, food cooking, and other anthropogenic sources were tracked separately throughout the simulation as they aged in the atmosphere. Results show that the source-oriented representation of particles with meteorological feedbacks in WRF/Chem changes the aerosol extinction coefficients, downward shortwave

  12. L'énergie: facteur d'intégration en Amérique du sud ? (Axe IX, Symposium 37)

    OpenAIRE

    Schausteck Le Prioux, Bruna

    2010-01-01

    L'énergie est une question stratégique pour toutes les nations et est la clé pour le développement économique et social. La question énergétique a été cruciale pour l'interdépendance et la coopération en Amérique du sud, donnant lieu à plusieurs interconnexions électriques depuis les années 1970 et gazières depuis les années 1990. Cependant, depuis quelques années, l'énergie ne semble plus accomplir son rôle intégrateur dans le sous-continent. Les épisodes de la non-exportation de gaz argenti...

  13. Chapitre 5. Le commerce au défi de l’inégale intégration du territoire rasūlide

    OpenAIRE

    Vallet, Éric

    2015-01-01

    Le Yémen intérieur est sans aucun doute le grand oublié de l’histoire du commerce transmaritime de l’océan Indien et de la mer Rouge, trop souvent perçu comme un simple commerce de transit à l’époque médiévale. L’étude des saisons du port d’Aden nous l’a pourtant amplement montré : deux produits venus des montagnes et des plaines de l’Arabie du Sud, la garance et les chevaux, jouaient un rôle déterminant dans le cycle des échanges adénis, notamment avec l’Inde. Les deux tarifs douaniers du Nū...

  14. Intégration à TRNSYS du noyau de CODYRUN, code de simulation thermo-aéraulique de bâtiments : le Type 59

    OpenAIRE

    Bastide, Alain; Boyer, Harry; Lauret, Philippe; Lucas, Franck; Garde, Francois; Garde, François

    2001-01-01

    National audience Ce papier traite de l'intégration à l'environnement TRNSYS du noyau de calcul d'un modèle développé depuis une dizaine d'années à l'Université de la Réunion, développement entrepris initialement en partenariat avec le CETHIL de l'INSA de Lyon. Il part du constat d'une segmentation des utilisateurs-développeurs en thermique des bâtiments, partagés entre un groupe sous environnement TRNSYS (type19 et 56 principalement) et l'autre mettant en œuvre des codes spécifiques (ESP,...

  15. Un modèle intégré de la demande totale d'énergie. Application à la province de Québec

    OpenAIRE

    Bernard, Jean-Thomas

    2001-01-01

    À cause du cadre réglementaire et des politiques gouvernementales qui s'appliquent à la demande d'énergie, celle-ci a reçu beaucoup d'attention de la part des développeurs de modèles. Dans cet article, je présente un modèle intégré de la demande totale d'énergie. Les principaux déterminants sont les prix relatifs des sources d'énergie (charbon, électricité, gaz naturel et pétrole), le niveau d'activité économique, la formation des ménages et la température. Des effets dynamiques permettent à ...

  16. Chimie intégrative pour la conception de matériaux poreux fonctionnels avancés et applications

    OpenAIRE

    Brun, Nicolas

    2010-01-01

    Une organisation contrôlée de la porosité offre l'opportunité de combiner les avantages structuraux des macropores (diamètres supérieures à 50 nm), assurant l'intégrité et l'interconnectivité de l'ossature du matériau, avec ceux des pores plus étroits (méso- et micropores), déployant des surfaces spécifiques réactives importantes. L'élaboration de telles architectures, dites " hiérarchisées ", à l'échelle du laboratoire représente un véritable défi physico-chimique. Dans ce contexte, ce trava...

  17. Professionnalisation et développement professionnel des enseignants dans un contexte d’intégration des TICE : le cas du Québec

    OpenAIRE

    Karsenti, Thierry; Grégoire, Pascal

    2015-01-01

    Contexte La question de la professionnalisation et du développement professionnel des formateurs universitaires du Québec dans un contexte d’intégration des TICE revêt plusieurs défis. En effet, même si les formateurs universitaires forment des enseignants du primaire et du secondaire aux TICE, de même qu’aux usages pédagogiques des TICE auprès des élèves, ils ne sont, eux, pas tenus d’être formés dans ce domaine. Autrement dit, dans les neuf universités du Québec qui forment de futurs maître...

  18. COST-STIC Cartes Orientées Services Transactionnels et Systèmes Transactionnels Intégrant des Cartes

    OpenAIRE

    Lecomte, Sylvain

    1998-01-01

    Le domaine d'application des cartes à microprocesseur est de plus en plus vaste (le secteur monétaire, la téléphonie, la santé). Dorénavant, la carte s'intègre dans des systèmes distribués (paiement sur Internet, téléphonie mobile). Ainsi, malgré l'apparition de nouvelles cartes utilisant des langages de programmation répandus (comme Java pour la JavaCard), le développement des applications carte, dans un milieu distribué et très sujet aux pannes, se révèle de plus en plus complexe. Le modèle...

  19. Modélisation intégrée et pérennisation des connaissances dans une approche PLM

    OpenAIRE

    Pernelle, Philippe; Lefebvre, Arnaud

    2006-01-01

    De nombreuses entreprises industrielles s'intéressent depuis déjà quelques années aux systèmes d'information capables de prendre en charge la totalité du processus de développement du produit. Ces systèmes, généralement regroupés sous le terme de PLM (Product Lifecycle Management) ou SIP (Système d'Information Produit), étendent le champ d'application initial des Systèmes de Gestion de Données Technique (ou PDM). Les évolutions technologiques et méthodologiques rendent plus attractif le choix...

  20. Introduction des progiciels intégrés dans les PME : évaluer les risques et compétences associés au projet

    OpenAIRE

    2009-01-01

    La communication présente les résultats, non définitifs, du projet PROJSI, financé par M@rsouin, sur l’année 2008. Les ERP (Entreprise Resource Planning) sont des progiciels d’intégration des différentes fonctions de l’organisation. Le choix d’adoption d’un ERP relève de la décision stratégique et sa mise en œuvre constitue un projet technique et organisationnel complexe. Au fil des ans, des méthodologies de gestion de projet ont été mises en place, sur la base des expériences d’implantation ...

  1. L'évolution de la théorie des contrats incomplets face à la dé-intégration verticale

    OpenAIRE

    Olivier Sautel

    2007-01-01

    L’objet de cet article consiste à éclairer les renouvellements de la théorie des Contrats Incomplets (TCI) initiée par Hart et Moore (1990) face au mouvement de dé-intégration verticale qui marque les structures industrielles. En effet, il s’opère une redéfinition progressive du rôle de la propriété des actifs au sein de cette théorie de la firme. La propriété des actifs n’est plus considérée comme l’instrument nécessaire et suffisant de la gestion des incitations. Au-delà de la possession ju...

  2. Procédé intégré de traitement du gaz naturel Integrated Process for Natural Gas Treatment

    OpenAIRE

    Larue J.; Lebas E.

    2006-01-01

    L'Institut français du pétrole a développé une nouvelle technique de traitement du gaz naturel, le procédé intégré IFPEXOL, basé sur une nouvelle mise en oeuvre de méthanol à basse température, qui incorpore dans un procédé unique les trois fonctions de déshydratation, extraction des liquides de gaz naturel (LGN) et désacidification. Le procédé IFPEXOL se compose de deux sections successives : une première section IFPEX-1 de déshydratation et d'extraction des LGN, une deuxième section IFPEX-2...

  3. Photonique intégrée nonlinéaire sur plate-formes CMOS compatibles pour applications du proche au moyen infrarouge

    OpenAIRE

    Carletti, Luca

    2015-01-01

    La photonique intégrée offre la possibilité d’exploiter un vaste bouquet de phénomènes optique nonlinéaires pour la génération et le traitement de signaux optiques sur des puces très compactes et à des débits potentiels extrêmement rapides. De nouvelles solutions et technologies de composants pourraient être ainsi réalisées, avec un impact considérable pour les applications télécom et datacom. L’utilisation de phénomènes optiques nonlinéaires (e.g. effet Kerr optique, effet Raman) permet même...

  4. Le règlement intérieur : un garde-fou nécessaire ? Le cas d'une entreprise sociale pour l'habitat

    OpenAIRE

    Emilie Maillart

    2011-01-01

    L'aspect juridique est omniprésent dans la gestion des ressources humaines d'une entreprise. Il faut quotidiennement composer avec les obligations légales qui incombent aux entreprises de droits privées. Ce mémoire a pour but de présenter le règlement intérieur, non pas comme un outil juridique, mais comme un outil de gestion des ressources humaines à la disposition de l'employeur. Il s'agit de mettre en évidence le fait que l'évolution de la réglementation du travail en France a favorisé la ...

  5. Agrégation de critères interactifs au moyen de l'intégrale de Choquet discrète

    OpenAIRE

    Marichal, Jean-Luc

    1999-01-01

    L'opérateur le plus souvent utilisé pour agréger des critères dans les problèmes d'aide multicritère à la décision est la moyenne arithmétique pondérée. Cependant, dans de nombreux problèmes pratiques, les critères interagissent, ce qui nécessite l'emploi d'un agrégateur plus général. Nous montrons que, sous des hypothèses assez naturelles, l'intégrale de Choquet discrète est un opérateur d'agrégation approprié qui généralise la moyenne arithmétique pondérée par la prise en compte de l'intera...

  6. Technologies informatiques à l'école primaire. De la modernité réformatrice à l'intégration pédagogique innovante.

    OpenAIRE

    Béziat, Jacques

    2003-01-01

    Après avoir posé le cadre lié à l'intégration des TIC à l'école, cette thèse fait une analyse des discours des enseignants d'école primaire qui se servent des TIC dans leur classe. Cette analyse porte sur des articles dans la presse professionnelle, des sites web scolaires et un travail d'enquête. Cette analyse est faite sur une période allant de 1970 à 2002, période d'émergence des TIC à l'école. Entre autre, il en ressort que, même si les enseignants ont souvent une pratique innovante audac...

  7. Conception et intégration d’un micro-initiateur sécurisé à base de micro-interrupteurs pyrotechniques sur silicium

    OpenAIRE

    Pennarun, Pierre

    2006-01-01

    Les travaux de thèse, ont porté sur la conception et la réalisation d’un micro-initiateur sécurisé sur silicium. Le système intègre outre la fonction initiation, plusieurs fonctions sécuritaires répondant aux besoins militaires : armement, désarmement et stérilisation. Le système est initialement sécurisé par la mise en cours circuit des deux contacts de l’initiateur. L’initiateur consiste en un élément chauffant sur membrane diélectrique permettant d’initier des charges pyrotechniques ave...

  8. Les pollutions dans l'air intérieur des bâtiments - Diagnostic - Incidences sur la santé.

    OpenAIRE

    Kuske, Martyna; Nicolas, Jacques

    2000-01-01

    Ce n’est qu’au cours des années 70 que certains problèmes de santé ont pu être directement associés à l’environnement intérieur des maisons. Les crises pétrolières ont stimulé une réduction de la consommation d’énergie, entraînant le renforcement de l'isolation thermique des maisons et une réduction de leur ventilation. Si l'objectif énergétique est atteint, il faut constater à présent que la plupart de ces actions ont provoqué l'augmentation des concentrations de certains polluants à...

  9. Varför, varför inte? : En studie om två skolors syn på läs- och skrivprogrammet Reading Recovery

    OpenAIRE

    Mellberg, Maria

    2010-01-01

    Syftet med studien är att undersöka, beskriva och problematisera Reading Recovery samt att ta reda på varför två nyzeeländska skolor har valt att behålla respektive sluta med programmet. Undersökningen baseras på fyra kvalitativa intervjuer samt en kvalitativ observation, vilka skedde på två skolor där den ena slutade med Reading Recovery för några år sedan och där den andra skolan fortfarande använder programmet. Undersökningen syftar inte till att jämföra de båda skolornas språkundervisning...

  10. L’utilisation de l’hydrolyse enzymatique pour la production de nanocellulose dans une stratégie de bioraffinage forestier intégré

    OpenAIRE

    Bombeck, Pierre-Louis; Hebert, Jacques; Richel, Aurore

    2016-01-01

    Introduction. Dans un monde qui cherche à se défaire de sa dépendance à la pétrochimie, le concept de bioraffinage de la biomasse forestière est de plus en plus étudié. Dans une recherche de valorisation maximale des composants de cette biomasse, la transformation de fibres de cellulose en nanocellulose séduit de plus en plus l’industrie papetière par sa haute valeur ajoutée. Littérature. Le concept de bioraffinage forestier intégré vise l’adaptation des usines de pâte à papier en bioraffi...

  11. La modélisation de l’immunité des circuits intégrés au-delà de 1 GHz

    OpenAIRE

    Op 'T Land, Sjoerd

    2014-01-01

    La compatibilité électromagnétique (CEM) est l'aptitude des produits électroniques à coexister au niveau électromagnétique. Dans la pratique, c'est une tâche très complexe que de concevoir des produits compatibles. L'arme permettant de concevoir des produits bon-du-premier-coup est la modélisation. Cette thèse étudie l'utilité et la faisabilité de la modélisation de l'immunité des circuits intégrés (CI) au-delà de 1 GHz. Si les pistes des circuits imprimés déterminent l'immunité rayonnée de c...

  12. Pourquoi une revue scientifique internationale portant sur l’intégration des TIC en pédagogie universitaire ?

    OpenAIRE

    Thierry Karsenti

    2004-01-01

    Quelques années après avoir réalisé un film destiné à l’éducation en 1911, Thomas Edison a dit : « Les livres seront incessamment désuets. Les étudiants apprendront bientôt à travers leurs yeux. Il est possible d’enseigner toutes les facettes du savoir humain par le film. Notre système d’éducation sera complètement transformé d’ici dix ans ». Depuis la promesse d’Edison de révolutionner l’enseignement par le film, les expériences d’intégration des technologies en pédagogie universitaire ont c...

  13. Transport aérien et intégration territoriale : l’exemple des Antilles françaises

    Directory of Open Access Journals (Sweden)

    2010-11-01

    Full Text Available IntroductionLe transport aérien, par sa rapidité, est un vecteur privilégié d’intégration spatiale. Dans le cas des îles de la Guadeloupe et de la Martinique, Départements Français d’Amérique situés à 7 000 km de leur métropole, l’activité aérienne est dominée par les liaisons transatlantiques qui sont les véritables supports de la continuité territoriale et qui doivent répondre à une mobilité de plus en plus forte des populations antillaises installées à leurs deux extrémités, ainsi qu’aux e...

  14. Stephen Kalberg, Les valeurs, les idées et les intérêts. Introduction à la sociologie de Max Weber

    OpenAIRE

    Belghanem, Ali

    2012-01-01

    Mal lue, mal traduite, souvent située par rapport à des dichotomies qu’elle a largement contribué à dépasser, l’œuvre de Max Weber connaît un regain d’intérêt. Après La sociologie historique et comparée de Max Weber (Paris, Éd. La Découverte, 2002), on peut désormais lire en français le deuxième livre que Stephen Kalberg, spécialiste internationalement reconnu de Max Weber, consacre à la revisite de l’œuvre de ce dernier. La préface du livre, signée par Alain Caillé et Philippe Chanial, assig...

  15. Résistance-Fer, du « réseau » à l’association : une dynamique corporative intéressée ?

    OpenAIRE

    Ribeill, Georges

    2011-01-01

    L’historien qui s’intéresse à Résistance-Fer a la chance de pouvoir bénéficier du riche fonds d’archives de cette association. Faute de bonnes volontés pour en perpétuer le fonctionnement, après un demi-siècle d’existence, la dissolution de cette association fut décidée lors son assemblée générale tenue à Cahors les 28 et 29 mai 1997 : il fut alors convenu que les archives seraient versées aux Archives nationales, et rendues entièrement libres d’accès. Auparavant, l’association avait publié t...

  16. Intéractions et autres processus physico-chimiques entre le chlore et les matrices cimentaires : rapport de recherche post-doctoral

    OpenAIRE

    BARBERON, Fabien; LABORATOIRE CENTRAL DES PONTS ET CHAUSSEES - LCPC

    2004-01-01

    La durabilité des ouvrages a toujours été un souci majeur du génie civil. En particulier, les ouvrages situés dans des zones climatiques agressives (côtes maritimes, montage etc.) subissent des agressions permanentes ou périodiques. Parmi les différents types d'agressions, la dégradation par le chlore, qui nous intéresse ici, suit un autre processus particulier. L'ion chlorure, présent naturellement dans l'eau ou les sols, pénètre dans le matériau par l'intermédiaire des pores. Au court du te...

  17. Effet de la visibilité du handicap et de l’expérience d’intégration sur la représentation sociale du handicap chez de jeunes collégiens

    OpenAIRE

    Kahina, Harma; Anne, Gombert; J-Yves, Roussey; ARCISZEWSKI, Thomas

    2012-01-01

    Cette recherche a pour objectif de repérer l’impact de l’intégration en milieu scolaire ordinaire de collégiens en situation de handicap sur la représentation sociale du handicap des autres élèves de la classe. L’effet de l’expérience d’intégration (le fait d’appartenir à une classe qui intègre ou non un élève handicapé) ainsi que celui de la visibilité du handicap (handicap visible comme l’Infirmité Motrice Cérébrale versus non visible, comme les Troubles Sévères des Apprentissages) ont été ...

  18. La collaboration entre les enseignants, les parents et les spécialistes portant sur des élèves ayant des besoins particuliers dans un contexte d'intégration scolaire

    OpenAIRE

    Razzano, Gelsomina; Ramel, Serge

    2012-01-01

    Intégration scolaire et collaboration sont les thèmes principaux de cette étude. Ces deux notions sont réunies afin de définir quelle peut être l’influence de la collaboration dans un contexte donné, celui de l’intégration. Pour l’intégration, on peut dire qu’avoir dans sa classe un élève différent peut être riche de sens. Aussi bien pour l’élève en question (qui peut ainsi vivre sa vie comme les autres) que pour le reste de la classe. L’école est un lieu où l’on apprend à se connaître,...

  19. Variabilité chimique et intérêt économique des huiles essentielles de deux menthes sauvages : Mentha pulegium (Fliou) et Mentha rotundifolia (Domrane) de l’ouest algérien.

    OpenAIRE

    TAALBI, Amina

    2016-01-01

    Notre travail s’est basé principalement sur une étude de la variabilité chimique et l’intérêt économique des huiles essentielles de deux menthes sauvages de l’ouest algérien: Mentha pulegium et Mentha rotundifolia. Ces deux menthes, largement répandue en Algérie, de la famille des Lamiaceae sont connus dans le monde pour leurs propriétés thérapeutiques (antiseptique, antinévralgique, analgésique…) et l’intérêt économique de leurs huiles essentielles....

  20. Enjeux des abonnements électroniques pour les centres de documentation d'aujourd'hui. Etude de cas : Intérêt des abonnements électroniques pour le CNDR SP

    OpenAIRE

    Colin, Marie

    2013-01-01

    Le CNDR SP est un centre de ressources spécialisées dans les soins palliatifs, le deuil, la fin de vie... Le service information-documentation du centre s'interroge sur l'intérêt des abonnements électroniques aux revues pour le Centre. Pour identifier s'il y a un intérêt, nous allons analyser en premier lieu l'existant, ensuite nous analyserons les besoins, et enfin, nous analyserons les offres tarifaires des différents acteurs. Ainsi, nous verrons que le mode d'abonnement qui convient le mie...

  1. Technical Note: Evaluation of the WRF-Chem "aerosol chemical to aerosol optical properties" module using data from the MILAGRO campaign

    Directory of Open Access Journals (Sweden)

    J. C. Barnard

    2010-04-01

    Full Text Available A comparison between observed aerosol optical properties from the MILAGRO field campaign, which took place in the Mexico City Metropolitan Area (MCMA during March 2006, and values simulated by the Weather Research and Forecasting (WRF-Chem model, reveals large differences. To help identify the source of the discrepancies, data from the MILAGRO campaign are used to evaluate the "aerosol chemical to aerosol optical properties" module implemented in the full chemistry version of the WRF-Chem model. The evaluation uses measurements of aerosol size distributions and chemical properties obtained at the MILAGRO T1 site. These observations are fed to the module, which makes predictions of various aerosol optical properties, including the scattering coefficient, Bscat; the absorption coefficient, Babs; and the single-scattering albedo, ϖ0; all as a function of time. Values simulated by the module are compared with independent measurements obtained from a photoacoustic spectrometer (PAS at a wavelength of 870 nm. Because of line losses and other factors, only "fine mode" aerosols with aerodynamic diameters less than 2.5 μm are considered here. Over a 10-day period, the simulations of hour-by-hour variations of Bscat are not satisfactory, but simulations of Babs and ϖ0 are considerably better. When averaged over the 10-day period, the computed and observed optical properties agree within the uncertainty limits of the measurements and simulations. Specifically, the observed and calculated values are, respectively: (1 Bscat, 34.1±5.1 Mm−1 versus 30.4±3.4 Mm−1; (2 Babs, 9.7±1.0 Mm−1 versus 11.7±1.2 Mm−1; and (3 ϖ0, 0.78±0.05 and 0.74±0.03. The discrepancies in values of ϖ0 simulated by the full WRF-Chem model thus cannot be attributed to the

  2. Sources, seasonality, and trends of southeast US aerosol: an integrated analysis of surface, aircraft, and satellite observations with the GEOS-Chem chemical transport model

    Science.gov (United States)

    Kim, P. S.; Jacob, D. J.; Fisher, J. A.; Travis, K.; Yu, K.; Zhu, L.; Yantosca, R. M.; Sulprizio, M. P.; Jimenez, J. L.; Campuzano-Jost, P.; Froyd, K. D.; Liao, J.; Hair, J. W.; Fenn, M. A.; Butler, C. F.; Wagner, N. L.; Gordon, T. D.; Welti, A.; Wennberg, P. O.; Crounse, J. D.; St. Clair, J. M.; Teng, A. P.; Millet, D. B.; Schwarz, J. P.; Markovic, M. Z.; Perring, A. E.

    2015-09-01

    We use an ensemble of surface (EPA CSN, IMPROVE, SEARCH, AERONET), aircraft (SEAC4RS), and satellite (MODIS, MISR) observations over the southeast US during the summer-fall of 2013 to better understand aerosol sources in the region and the relationship between surface particulate matter (PM) and aerosol optical depth (AOD). The GEOS-Chem global chemical transport model (CTM) with 25 × 25 km2 resolution over North America is used as a common platform to interpret measurements of different aerosol variables made at different times and locations. Sulfate and organic aerosol (OA) are the main contributors to surface PM2.5 (mass concentration of PM finer than 2.5 μm aerodynamic diameter) and AOD over the southeast US. OA is simulated successfully with a simple parameterization, assuming irreversible uptake of low-volatility products of hydrocarbon oxidation. Biogenic isoprene and monoterpenes account for 60 % of OA, anthropogenic sources for 30 %, and open fires for 10 %. 60 % of total aerosol mass is in the mixed layer below 1.5 km, 25 % in the cloud convective layer at 1.5-3 km, and 15 % in the free troposphere above 3 km. This vertical profile is well captured by GEOS-Chem, arguing against a high-altitude source of OA. The extent of sulfate neutralization (f = [NH4+]/(2[SO42-] + [NO3-]) is only 0.5-0.7 mol mol-1 in the observations, despite an excess of ammonia present, which could reflect suppression of ammonia uptake by OA. This would explain the long-term decline of ammonium aerosol in the southeast US, paralleling that of sulfate. The vertical profile of aerosol extinction over the southeast US follows closely that of aerosol mass. GEOS-Chem reproduces observed total column aerosol mass over the southeast US within 6 %, column aerosol extinction within 16 %, and space-based AOD within 8-28 % (consistently biased low). The large AOD decline observed from summer to winter is driven by sharp declines in both sulfate and OA from August to October. These declines

  3. The role of horizontal model resolution in assessing the transport of CO in a middle latitude cyclone using WRF-Chem

    Directory of Open Access Journals (Sweden)

    C. A. Klich

    2013-06-01

    Full Text Available We use the Weather Research and Forecasting with Chemistry (WRF-Chem online chemical transport model to simulate a middle latitude cyclone in East Asia at three different horizontal resolutions (45, 15, and 5 km grid spacing. The cyclone contains a typical warm conveyor belt (WCB with an embedded squall line that passes through an area having large surface concentrations (>400 ppbv of carbon monoxide (CO. Model output from WRF-Chem is used to compare differences between the large-scale CO vertical transport by the WCB (the 45 km simulation with the smaller-scale transport due to its convection (the 5 km simulation. Forward trajectories are calculated from WRF-Chem output using HYSPLIT. At 45 km grid spacing, the WCB exhibits gradual ascent, lofting surface CO to 6–7 km. Upon reaching the warm front, the WCB and associated CO ascend more rapidly and later turn eastward over the Pacific Ocean. Convective transport at 5 km resolution with explicitly resolved convection occurs much more rapidly, with surface CO lofted to altitudes greater than 10 km in 1 h or less. We also compute CO vertical mass fluxes to compare differences in transport due to the different grid spacings. Upward CO flux exceeds 110 000 t h−1 in the domain with explicit convection when the squall line is at peak intensity, while fluxes from the two coarser resolutions are an order of magnitude smaller. Specific areas of interest within the 5 km domain are defined to compare the magnitude of convective transport to that within the entire 5 km region. Although convection encompasses only a small portion of the 5 km domain, it is responsible for ~40% of the upward CO transport. We also examine the vertical transport due to a short wave trough and its associated area of convection, not related to the cyclone, that lofts CO to the upper troposphere. Results indicate that fine-scale resolution with explicitly resolved convection is important when assessing the vertical transport of

  4. Small-Angle X-Ray Scattering on the ChemMatCARS Beamline at the Advanced Photon Source: A Study of Shear-Induced Crystallisation in Polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, D.; Hanley, T.; Knott, R.; Cookson, D. (CRC); (ANSTO)

    2008-09-08

    The first ever time-resolved small-angle X-ray scattering (SAXS) data from the undulator 15-ID-D beamline (ChemMatCARS) are presented. A 1.3 {angstrom} (9.54 keV) X-ray beam was selected to study the structure development in a polypropylene sample during shear-induced crystallization. A Linkam CSS450 shear cell provided the temperature and shear control. The polypropylene was first melted and then quenched to the crystallization temperature, where a step shear was applied. The SAXS data were collected using a Bruker 6000 CCD detector, which provided images of excellent resolution. The SAXS images (with 180{sup o} rotational symmetry) indicated that the polypropylene crystallizes with a high degree of anisotropy, and the lamellae are oriented perpendicular to the flow direction.

  5. Comment on 'The diatomic dication CuZn{sup 2+} in the gas phase' [J. Chem. Phys. 135, 034306 (2011)

    Energy Technology Data Exchange (ETDEWEB)

    Fiser, Jiri [Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 40 Prague 2 (Czech Republic); Diez, Reinaldo Pis [Departamento de Quimica, CEQUINOR, Centro de Quimica Inorganica (CONICET, UNLP), Facultad de Ciencias Exactas, UNLP, CC 962, 1900 La Plata (Argentina); Franzreb, Klaus [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287 (United States); Alonso, Julio A. [Departamento de Fisica Teorica, Universidad de Valladolid, E-47011 Valladolid (Spain)

    2013-02-21

    In this Comment, the density functional theory (DFT) calculations carried out by Diez et al. [J. Chem. Phys. 135, 034306 (2011)] are revised within the framework of the coupled-cluster single double triple method. These more sophisticated calculations allow us to show that the {sup 2}{Sigma}{sup +} electronic ground state of CuZn{sup 2+}, characterized as the metastable ground state by DFT calculations, is a repulsive state instead. The {sup 2}{Delta} and {sup 2}{Pi} metastable states of CuZn{sup 2+}, on the other hand, should be responsible for the formation mechanism of the dication through the near-resonant electron transfer CuZn{sup +}+ Ar{sup +}{yields} CuZn{sup 2+}+ Ar reaction.

  6. PREP-CHEM-SRC – 1.0: a preprocessor of trace gas and aerosol emission fields for regional and global atmospheric chemistry models

    Directory of Open Access Journals (Sweden)

    S. R. Freitas

    2011-05-01

    Full Text Available The preprocessor PREP-CHEM-SRC presented in the paper is a comprehensive tool aiming at preparing emission fields of trace gases and aerosols for use in atmospheric-chemistry transport models. The considered emissions are from the most recent databases of urban/industrial, biogenic, biomass burning, volcanic, biofuel use and burning from agricultural waste sources. For biomass burning, emissions can be also estimated directly from satellite fire detections using a fire emission model included in the tool. The preprocessor provides emission fields interpolated onto the transport model grid. Several map projections can be chosen. The inclusion of these emissions in transport models is also presented. The preprocessor is coded using Fortran90 and C and is driven by a namelist allowing the user to choose the type of emissions and the databases.

  7. PREP-CHEM-SRC - 1.0: a preprocessor of trace gas and aerosol emission fields for regional and global atmospheric chemistry models

    Science.gov (United States)

    Freitas, S. R.; Longo, K. M.; Alonso, M. F.; Pirre, M.; Marecal, V.; Grell, G.; Stockler, R.; Mello, R. F.; Sánchez Gácita, M.

    2011-05-01

    The preprocessor PREP-CHEM-SRC presented in the paper is a comprehensive tool aiming at preparing emission fields of trace gases and aerosols for use in atmospheric-chemistry transport models. The considered emissions are from the most recent databases of urban/industrial, biogenic, biomass burning, volcanic, biofuel use and burning from agricultural waste sources. For biomass burning, emissions can be also estimated directly from satellite fire detections using a fire emission model included in the tool. The preprocessor provides emission fields interpolated onto the transport model grid. Several map projections can be chosen. The inclusion of these emissions in transport models is also presented. The preprocessor is coded using Fortran90 and C and is driven by a namelist allowing the user to choose the type of emissions and the databases.

  8. QSAR screening of 70,983 REACH substances for genotoxic carcinogenicity, mutagenicity and developmental toxicity in the ChemScreen project

    DEFF Research Database (Denmark)

    Wedebye, Eva Bay; Dybdahl, Marianne; Nikolov, Nikolai Georgiev;

    2015-01-01

    The ChemScreen project aimed to develop a screening system for reproductive toxicity based on alternative methods. QSARs can, if adequate, contribute to the evaluation of chemical substances under REACH and may in some cases be applied instead of experimental testing to fill data gaps for...... were used to reach overall predictions of substances with potential effects with the following result: 6.5% genotoxic carcinogens, 16.3% mutagens, 11.5% developmental toxicants. These results are similar to findings in earlier QSAR and experimental studies of chemical inventories, and illustrate how...... QSAR predictions may be used to identify potential genotoxic carcinogens, mutagens and developmental toxicants by high-throughput virtual screening....

  9. Hydrostatic, uniaxial, and triaxial compression tests on unpoled "Chem-prep" PZT 95/5-2Nb ceramic within temperature range of -55 to 75 degrees C.

    Energy Technology Data Exchange (ETDEWEB)

    Zeuch, David Henry; Montgomery, Stephen Tedford; Lee, Moo Yul; Hofer, John H.

    2003-10-01

    Sandia is currently developing a lead-zirconate-titanate ceramic 95/5-2Nb (or PNZT) from chemically prepared ('chem-prep') precursor powders. Previous PNZT ceramic was fabricated from the powders prepared using a 'mixed-oxide' process. The specimens of unpoled PNZT ceramic from batch HF803 were tested under hydrostatic, uniaxial, and constant stress difference loading conditions within the temperature range of -55 to 75 C and pressures to 500 MPa. The objective of this experimental study was to obtain mechanical properties and phase relationships so that the grain-scale modeling effort can develop and test its models and codes using realistic parameters. The stress-strain behavior of 'chem-prep' PNZT under different loading paths was found to be similar to that of 'mixed-oxide' PNZT. The phase transformation from ferroelectric to antiferroelectric occurs in unpoled ceramic with abrupt increase in volumetric strain of about 0.7 % when the maximum compressive stress, regardless of loading paths, equals the hydrostatic pressure at which the transformation otherwise takes place. The stress-volumetric strain relationship of the ceramic undergoing a phase transformation was analyzed quantitatively using a linear regression analysis. The pressure (P{sub T1}{sup H}) required for the onset of phase transformation with respect to temperature is represented by the best-fit line, P{sub T1}{sup H} (MPa) = 227 + 0.76 T (C). We also confirmed that increasing shear stress lowers the mean stress and the volumetric strain required to trigger phase transformation. At the lower bound (-55 C) of the tested temperature range, the phase transformation is permanent and irreversible. However, at the upper bound (75 C), the phase transformation is completely reversible as the stress causing phase transformation is removed.

  10. Using WRF/Chem, in-situ observations, and CALIPSO data to simulate smoke plume signatures on high-latitude pixels

    Science.gov (United States)

    Madden, James Michael

    The transport of wildfire aerosols provides concerns to people at or near downwind propagation. Concerns include the health effects of inhalation by inhabitants of surrounding communities and fire crews, the environmental effects of the wet and dry deposition of acids and particles, and the effects on the atmosphere through the scattering and absorption of solar radiation. Therefore, as the population density increases in Arctic and sub-Arctic areas, improving wildfire detection increasingly becomes necessary. Efforts to improve wildfire detection and forecasting would be helped if additional focus was directed toward the distortion of pixel geometry that occurs near the boundaries of a geostationary satellite's field of view. At higher latitudes, resolution becomes coarse due to the curvature of the Earth, and pixels toward the boundaries of the field of view become difficult to analyze. To assess whether it is possible to detect smoke plumes in pixels at the edge of a geostationary satellite's field of view, several analyses were performed. First, a realistic, four-dimensional dataset was created from Weather Research and Forecasting model coupled with Chemistry (WRF/Chem) output. WRF/Chem output was statistically compared to ground observations through the use of skill scores. Output was also qualitatively compared to vertical backscatter and depolarization products from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite. After the quantitative and qualitative examinations deemed the model output to be realistic, synthetic pixels were constructed, appropriately sized, and used with the realistic dataset to examine the characteristic signatures of a wildfire plume. After establishing a threshold value, the synthetic pixels could distinguish between clean and smoke-polluted areas. Thus, specialized retrieval algorithms could be developed for smoke detection in strongly distorted pixels at the edge of a geostationary satellite

  11. Modeling of low-temperature plasmas generated using laser-induced breakdown spectroscopy: the ChemCam diagnostic tool on the Mars Science Laboratory Rover

    Science.gov (United States)

    Colgan, James

    2016-05-01

    We report on efforts to model the low-temperature plasmas generated using laser-induced breakdown spectroscopy (LIBS). LIBS is a minimally invasive technique that can quickly and efficiently determine the elemental composition of a target and is employed in an extremely wide range of applications due to its ease of use and fast turnaround. In particular, LIBS is the diagnostic tool used by the ChemCam instrument on the Mars Science Laboratory rover Curiosity. In this talk, we report on the use of the Los Alamos plasma modeling code ATOMIC to simulate LIBS plasmas, which are typically at temperatures of order 1 eV and electron densities of order 10 16 - 17 cm-3. At such conditions, these plasmas are usually in local-thermodynamic equilibrium (LTE) and normally contain neutral and singly ionized species only, which then requires that modeling must use accurate atomic structure data for the element under investigation. Since LIBS devices are often employed in a very wide range of applications, it is therefore desirable to have accurate data for most of the elements in the periodic table, ideally including actinides. Here, we discuss some recent applications of our modeling using ATOMIC that have explored the plasma physics aspects of LIBS generated plasmas, and in particular discuss the modeling of a plasma formed from a basalt sample used as a ChemCam standard1. We also highlight some of the more general atomic physics challenges that are encountered when attempting to model low-temperature plasmas. The Los Alamos National Laboratory is operated by Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under Contract No. DE-AC5206NA25396. Work performed in conjunction with D. P. Kilcrease, H. M. Johns, E. J. Judge, J. E. Barefield, R. C. Wiens, S. M. Clegg.

  12. Sensitivities of WRF-Chem to dust emission schemes and land surface properties in simulating dust cycles during springtime over East Asia

    Science.gov (United States)

    Su, Lin; Fung, Jimmy C. H.

    2015-11-01

    The sensitivities of Weather Research and Forecasting model coupled with chemistry (WRF-Chem) to the Air Force Weather Agency (AFWA) and Shao2011 (S11) dust emission schemes, and to various land surface properties generated from United States Geological Survey (USGS) and Beijing Normal University (BNU) soil data over East Asia for spring 2012, are examined in this study. The results show that the dust emissions generated with the S11 scheme are 2-5 times that generated with the AFWA emission scheme, with emissions ranging from 0.2-1 Tg/d over East Asia in the relevant period. The AFWA emission scheme omits almost the entire Gobi desert and produces low dust emissions, whereas large amounts of dust emission in this region are produced with the S11 emission scheme, regardless of whether USGS or BNU soil data are used. The surface particulate matter 10 (PM10) concentrations are reasonably well reproduced by the model with different configurations. However, the S11 emission scheme has better performance in simulating the surface PM10 concentrations than the AFWA scheme, especially near the Gobi desert. Comparisons with satellite-based observations suggest that WRF-Chem gives better performance with S11 emission scheme in reproducing the horizontal and vertical distribution of aerosol optical properties. The discrepancy between the performances of the AFWA and S11 emission schemes is mainly due to the underestimation of the dust emission over the Gobi desert by the AFWA scheme, which scales the dust emission directly based on the erodibility factor, indicating that the erodibility factor over the Gobi desert is highly underestimated and highlighting an urgent need to improve the erodibility data set.

  13. S’exercer à l’empathie : une expérience pédagogique en design d’intérieur

    Directory of Open Access Journals (Sweden)

    Rabah Bousbaci

    2010-11-01

    Full Text Available All professions have obligations to the public they serve, i.e.: the patient for physicians, psychoa- nalysts, or nurses; the client for lawyers; the consumer for managers; etc. The user or occupant of the built environment is the intended public of interior design services. How do interior design students learn to imagine the occupants of the built environments they design? The concept of empathy, commonly defined as the capacity of identification with and understanding of another’s situation, feelings, and motives, is particularly suitable to explore this attitude. This paper has two parts. The first one presents an interior design academic exercise where students learn to imagine the occupants of their design project by using a methodological tool called an “ethical compass”. The compass is composed of three poles, which remind the three fundamental rela- tions in the human condition as they were considered in the Stoic tradition: man’s relation to oneself, to others, and to nature. In the second part, the paper outlines several theoretical elements, which help to understand, to strengthen, and eventually to make progress about some of the conceptual bases that underline this approach. Mainly, it outlines important ethical theories and specific approaches to the concept of empathy.RÉSUMÉLes professionnels ont par définition un public bénéficiaire de leurs services : le patient pour le médecin, le psychologue ou l’infirmière ; le client pour l’avocat ; le consommateur pour le ges- tionnaire d’une entreprise commerciale ; etc. L’usager ou l’habitant du cadre bâti constitue un des destinataires des services professionnels du designer d’intérieur. De quelle manière peut-on apprendre aux étudiants/futurs professionnels du design d’intérieur à se mettre à la place de l’usager/habitant des espaces qu’ils conçoivent ? Le concept de l’empathie, communément décrit comme la capacité de se mettre à la place

  14. Revenir sur ses pas. Le pèlerinage à Chalma (Mexique et l’intégration d’un ethnologue « porteur »

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Rodríguez Lizana

    2009-03-01

    Full Text Available Revenir sur ses pas. Le pèlerinage à Chalma (Mexique et l’intégration d’un ethnologue « porteur ». La plupart des études ethnologiques du pèlerinage se focalisent sur le point de vue des dévots qui font le parcours pour aller à la rencontre d’un saint, d’un dieu, etc. Or, à Milpa Alta, c’est la Vierge sous la forme d’une statue qui est supposée faire le pèlerinage en allant à la rencontre du Seigneur de Chalma. Pour essayer de saisir la logique des comportements dans l’espace et dans le social, j’ai participé à trois reprises au pèlerinage et j’ai réalisé un film. Ces moments précis de l’enquête ont contribué à définir mon expérience ethnographique et notamment mon intégration dans le village. En effet, lors des entretiens, mes interlocuteurs parlaient du pèlerinage comme d’une activité qui n’est pas transmissible par la description verbalisée mais uniquement par la réalisation concrète du parcours pèlerin. Autrement dit, pour comprendre certaines séquences rituelles du pèlerinage, il fallait y participer personnellement. Je reviens ici sur les étapes de mon intégration qui ont permis que j’accède au déploiement de la hiérarchie sociale, au rapport entre les vivants et les morts, au mouvement structurel qui anime le village de Milpa Alta vers l’extérieur.Retracing one’s steps. The pilgrimage to Chalma (Mexico and the integration of a “bearer” ethnologist. Most ethnological studies of pilgrimage focus on the point of view of the pilgrims who make the journey to visit a saint, a god, etc. But in Milpa Alta, it is the Virgin in the form of a statue who is supposed to do the pilgrimage by going to meet the Lord of Chalma. I took part in the pilgrimage three times and made a film, in an attempt to understand the logic of behaviours on both the spatial and social levels. These precise moments of the survey played a part in defining my ethnographic experience and, in particular

  15. Intégrer les Tice à une approche cognitive de la grammaire du discours How to integrate ICT into a cognitive approach of a discourse grammar?

    Directory of Open Access Journals (Sweden)

    Muriel Barbazan

    2011-09-01

    Full Text Available Si l'on a pour objectif de favoriser un apprentissage de la grammaire évaluable à l'aune des performances communicatives réelles des apprenants, il est utile d'identifier préalablement un cadre de travail qui respecte les processus cognitifs de production et de compréhension. Dans ce cadre, cet article envisage la question de la reformulation des contenus grammaticaux pour cibler l'apprentissage guidé de la langue telle qu'elle est mise en œuvre dans le "discours". Pour ce faire, on illustrera l'intérêt d'une démarche descriptive associant les deux pistes suivantes : a intégrer à la description grammaticale des prototypes de situations d'interactions verbales en relation avec les significations données aux outils grammaticaux. Parallèlement, b mettre en relation les fonctions des outils grammaticaux avec des types de plans textuels tout en insistant sur leur rôle de marqueurs de la macrostructure (repérage des unités textuelles. L'objet de cet article sera ensuite d'explorer les possibilités qu'offrent les Tice pour un apprentissage guidé ciblant l'acquisition de routines grammaticales adaptées à la production / réception du discours en situation. L'accent sera mis sur les activités de compréhension et de réorganisation unifiée des connaissances et savoir-faire grammaticaux, tout en soulignant l'intérêt des Tice pour favoriser en FLE la mise en œuvre effective et interactive de la L2. À partir d'exemples d'activités ou de possibilités d'exploitation de divers outils, cette seconde partie servira ainsi d'illustration aux axes descriptifs et aux orientations didactiques préalablement définis.In the light of results from psycholinguistics and cognitive psychology concerning learning models and verbal production processes, this article follows up two objectives. Before exploring the potential development of grammatical activities in a digital learning environment, the first part will explore how we can conceive

  16. Intégration du système de mesure de foudre au Säntis avec un capteur de champ électrique installé par la HES-SO Valais

    OpenAIRE

    Lovey, Jérôme; Pavanello, Davide

    2012-01-01

    Ce projet a pour but d’intégrer un capteur de champ électrostatique à l’installation de mesure de signaux de foudre en opération au Mont Säntis. Cette installation, conçue à des fins de recherche, pourra aussi servir d’outil d’alerte pour orage imminent.

  17. Le nouveau Xinjiang : intégration et recompositions territoriales d’une périphérie chinoise

    Directory of Open Access Journals (Sweden)

    Alain Cariou

    2009-06-01

    Full Text Available Le Xinjiang est généralement présenté comme l’archétype de la périphérie chinoise en raison de son enclavement, de son retard de développement et de son peuplement constitué de minorités nationales. Pourtant, depuis peu, cette périphérie présente le paradoxe d’un développement accéléré qui la singularise des autres provinces intérieures de la Chine par son premier rand pour son IDH et son PIB. Cette évolution s’explique par son rôle géostratégique dû à sa richesse en ressources naturelles et à sa position frontalière ce qui lui confère la fonction de « tête de pont » commerciale de la Chine en Asie centrale. L’achèvement du réseau routier et ferroviaire transcontinental porteur de migrations Han participe de la politique nationale de sécurisation et d’intégration économique et culturelle du Xinjiang ce que traduit le rapide déclin des minorités nationales.This paper analyses recent geographic change in the Xinjiang Uygur Autonomous Region. Xinjiang plays a geostratégic role in China due to abundance of natural resources such as oil, gas an coal but also for its particular geographic location in the heartland of Central Asia. The area gives to China an high potentiel for trade with the newly independent Central Asian republics and Eurasia. That’s the reason why central government take active measures for an acceleration of the economic development in the region with the aim of promoting regional security, cultural and économic integration. Nowadays, an unprecedent change taken place in Xinjiang with the improvements in transportation infrastructure. The expansion of the transcontinantal railway and highways between Est China to Central Asia has created a fast growing economies and the increase of Han migration. The rapide decline of the proportion of ethnic minority nationality is the result of a political strategy of Chinese national expansion and territorial intergation in order to control

  18. Modeling of Soil Erosion by IntErO model: The Case Study of the Novsicki Potok Watershed, of the Prokletije high mountains of Montenegro

    Science.gov (United States)

    Spalevic, Velibor; Al-Turki, Ali M.; Barovic, Goran; Leandro Naves Silva, Marx; Djurovic, Nevenka; Soares Souza, Walisson; Veloso Gomes Batista, Pedro; Curovic, Milic

    2016-04-01

    The application of soil conservation programs to combat erosion and sedimentation are significantly contributing to the protection of the natural resources. Watershed management practices include the assessment of Physical-Geographical, Climate, Geological, Pedological characteristics, including the analysis of Land Use of the regions concerned. The policy makers are increasingly looking for the different land uses and climatic scenarios that can be used for valuable projections for watershed management. To increase knowledge about those processes, use of hydrological and soil erosion models is needed and that is allowing quantification of soil redistribution and sediment productions. We focused on soil erosion processes in one of Northern Montenegrin mountain watersheds, the Novsicki Potok Watershed of the Polimlje River Basin, using modeling techniques: the IntErO model for calculation of runoff and soil loss. The model outcomes were validated through measurements of lake sediment deposition at the Potpec hydropower plant dam. Our findings indicate a medium potential of soil erosion risk. With 464 m³ yr‑1 of annual sediment yield, corresponding to an area-specific sediment yield of 270 m³km-2 yr‑1, the Novsicki Potok drainage basin belongs to the Montenegrin basins with the medium sediment discharge; according to the erosion type, it is surface erosion. The value of the Z coefficient was calculated on 0.403, what indicates that the river basin belongs to 3rd destruction category (of five). Our results suggest that the calculated peak discharge from the river basin was 82 m3s-1 for the incidence of 100 years. According to our analysis there is a possibility for large flood waves to appear in the studied river basin. With this research we, to some extent, improved the knowledge on the status of sediment yield and runoff of the river basins of Montenegro, where the map of Soil erosion is still not prepared. The IntErO model we used in this study is relatively

  19. Métarecherche sur les effets de l’intégration des TIC en pédagogie collégiale

    Directory of Open Access Journals (Sweden)

    Christian Barrette

    2009-01-01

    Full Text Available [Français] L’Association pour la recherche au collégial soutient depuis 2003 une métarecherche sur les meilleures pratiques en matière d’intégration pédagogique des TIC. Dans une première phase, une méta-analyse et une métasynthèse de recherches empiriques réalisées dans les collèges et les cégeps ont fait émerger un modèle heuristique des déterminants d’une intégration pédagogique réussie des TIC. Lors d’une deuxième phase, des entrevues de personnes expertes ont permis d’expliciter leurs représentations puis de les confronter au modèle initial. Il en résulte que les personnes expertes confirment les résultats de la recherche empirique et ajoutent de nouvelles dimensions au modèle. La troisième phase de la métarecherche, actuellement en cours, vise le transfert des résultats auprès de conseillères et de conseillers technopédagogiques. Réalisées dans une approche de théorisation ancrée, les activités menées conjointement avec ces professionnels continuent d’approfondir et d’élargir les dimensions prises en compte par le modèle de l’ARC. [English] Since 2003, the Association pour la recherche au collégial supports a metaresearch on the best practices in the field of IT pedagogical integration. During its first stage, both a meta-analysis and a metasynthesis of empirical data drawn from experiments conducted in various colleges have brought to light a heuristic model of the determinants of a successful pedagogical integration of IT. During a second stage, interviews with experts have allowed to elicit their representations and confront them with the initial model. The conclusions are that the experts both confirm the primary results coming from empirical researches and add new dimensions to be considered. The third stage of the metaresearch, still active, transfers the results toward a community of technopedagogical advisors. Following a grounded theory approach, activities conducted with

  20. Traitement automatisé de la néologie : pourquoi et comment intégrer l'analyse thématique ?

    Directory of Open Access Journals (Sweden)

    Gérard Christophe

    2014-07-01

    L’originalité du Logoscope le distingue des outils similaires existants : contrairement ces derniers, l’acquisition semi-automatisée des néologismes intègre d’emblée les conditions textuelles et discursives de l’innovation lexicale. Cette direction de recherche est en effet essentielle : dans le domaine de la néologie, tout ce que nous savons déjà de la morphologie d’une langue et des types de formation des mots devrait être complété par une description des conditions de production et de réception des néologismes, étant donné qu’aucune création lexicale ne se produit jamais en dehors d’un texte particulier et d’une situation de communication définie. Pratiquement, nous proposons donc un outil d’acquisition et une ressource néologique qui documente non seulement les néologismes au moyen des variables traditionnelles (morphologie, formation du mot, parties du discours, etc., mais aussi au moyen de variables chargées de décrire dans quel contexte communicationnel précis ils apparaissent.

  1. Modélisation de l'intégration de ressources TAL pour l'apprentissage des langues : la plateforme MIRTO

    Directory of Open Access Journals (Sweden)

    Claude Ponton

    2005-11-01

    Full Text Available Le présent article se focalise sur le développement d'outils de traitement automatique des langues (TAL pour l'apprentissage des langues assisté par ordinateur (ALAO. Après avoir identifié les limitations inhérentes aux outils d'ALAO dépourvus de composantes TAL, nous décrivons le cadre général du projet MIRTO, une plateforme de création d'activités pédagogiques fondé sur des outils TAL en développement au sein de notre laboratoire. Cette plateforme est organisée en quatre couches distinctes et successives : fonctions, scripts, activités et scénarios. À travers plusieurs exemples, nous expliquons en quoi l'architecture de MIRTO permet l'implantation de fonctions TAL classiques au sein de scripts, lesquels facilitent la conception, sans compétence informatique préalable, d'activités didactiques, elles-mêmes éventuellement intégrées au sein de séquences plus complexes, ou scénarios.

  2. Secondary structure of synthetic oligopeptides

    CERN Document Server

    Martinez-Insua, M

    2000-01-01

    The secondary structure of three hydrophobic peptides P2, PRMo and P4 was studied by a combination of Circular Dichroism (CD), Fourier Transform InfraRed (FTIR) and Photoinduced Electron Transfer (PET). These peptides were fluorescence labelled in the central part of the backbone and contained two modified glutamic acid residues (relative positions i, i+4): one conjugated with the fluorescence methoxynapththalene electron donor (DON) and the other with the piperidone electron acceptor (ACC). The three peptides were synthesised to study the length dependence of the switch between alpha-helix and the 3 sub 1 sub 0 -helix conformations, previously observed for peptide PRM1 (Hungerford et al., Angew. Chem., Int. Ed. Engl., 1996, 35, 326-329). The CD and FTIR data indicated that peptides P2, PRMo and P4 adopt alpha-helical conformation in organic media in the temperature range studied and no conformational switch was detected. Furthermore, a mathematical correlation was observed in the PET data, questioning the ag...

  3. High-performance piezoelectric nanogenerators for self-powered nanosystems: quantitative standards and figures of merit

    Science.gov (United States)

    Wu, Wenzhuo

    2016-03-01

    Harvesting energies from the atmosphere cost-effectively is critical for both addressing worldwide long-term energy needs at the macro-scale, and achieving the sustainable maintenance-free operation of nanodevices at the micro-scale (Wang and Wu 2012 Angew. Chem. Int. Ed. 51 11700-21). Piezoelectric nanogenerator (NG) technology has demonstrated its great application potential in harvesting the ubiquitous and abundant mechanical energy. Despite of the progress made in this rapidly-advancing field, a fundamental understanding and common standard for consistently quantifying and evaluating the performance of the various types of piezoelectric NGs is still lacking. In their recent study Crossley and Kar-Narayan (2015 Nanotechnology 26 344001), systematically investigated dynamical properties of piezoelectric NGs by taking into account the effect of driving mechanism and load frequency on NG performance. They further defined the NGs’ figures of merit as energy harvested normalized by applied strain or stress for NGs under strain-driven or stress-driven conditions, which are commonly seen in the vibrational energy harvesting. This work provides new insight and a feasible approach for consistently evaluating piezoelectric nanomaterials and NG devices, which is important for designing and optimizing nanoscale piezoelectric energy harvesters, as well as promoting their applications in emerging areas e.g. the internet of things, wearable devices, and self-powered nanosystems.

  4. HOCCO versus OCCO: Comparative spectroscopy of the radical and diradical reactive intermediates

    Science.gov (United States)

    Dixon, Andrew R.; Xue, Tian; Sanov, Andrei

    2016-06-01

    We present a photoelectron imaging study of three glyoxal derivatives: the ethylenedione anion (OCCO-), ethynediolide (HOCCO-), and glyoxalide (OHCCO-). These anions provide access to the corresponding neutral reactive intermediates: the OCCO diradical and the HOCCO and OHCCO radicals. Contrasting the straightforward deprotonation pathway in the reaction of O- with glyoxal (OHCCHO), which is expected to yield glyoxalide (OHCCO-), OHCCO- is shown to be a minor product, with HOCCO- being the dominant observed isomer of the m/z = 57 anion. In the HOCCO/OHCCO anion photoelectron spectrum, we identify several electronic states of this radical system and determine the adiabatic electron affinity of HOCCO as 1.763(6) eV. This result is compared to the corresponding 1.936(8) eV value for ethylenedione (OCCO), reported in our recent study of this transient diradical [A. R. Dixon, T. Xue, and A. Sanov, Angew. Chem., Int. Ed. 54, 8764-8767 (2015)]. Based on the comparison of the HOCCO-/OHCCO- and OCCO- photoelectron spectra, we discuss the contrasting effects of the hydrogen connected to the carbon framework or the terminal oxygen in OCCO.

  5. Supramolecular polymer transformation: a kinetic study.

    Science.gov (United States)

    Baram, Jonathan; Weissman, Haim; Rybtchinski, Boris

    2014-10-16

    Investigation of supramolecular kinetics is essential for elucidating self-assembly mechanisms. Recently, we reported on a noncovalent system involving a bolaamphiphilic perylene diimide dimer that is kinetically trapped in water but can rearrange into a different, more ordered assembly in water/THF mixtures ( Angew. Chem. Int. Ed. 2014 , 53 , 4123 ). Here we present a kinetic mechanistic study of this process by employing UV-vis spectroscopy. The transformation exhibits a rapid decrease in the red-shifted absorption band, which is monitored in order to track the kinetics at different temperatures (15-50 °C) and concentrations. Fitting the data with the 1D KJMA (Kolmogorov-Johnson-Mehl-Avrami) model affords the activation parameters. The latter as well as seeding experiments indicates that the transformation occurs without the detachment of covalent units, and that hydration dynamics plays a significant role in nucleation, with entropic factors being dominant. Switching off the transformation, and the formation of off-pathway intermediates were observed upon heating to temperatures above 55 °C. These insights into kinetically controlled supramolecular polymer transformations provide mechanistic information that is needed for a fundamental understanding of noncovalent processes, and the rational design of noncovalent materials. PMID:25238603

  6. The role of ions in the self-healing behavior of soft particle suspensions

    Science.gov (United States)

    Scotti, Andrea; Gasser, Urs; Herman, Emily S.; Pelaez-Fernandez, Miguel; Han, Jun; Menzel, Andreas; Lyon, L. Andrew; Fernández-Nieves, Alberto

    2016-05-01

    Impurities in crystals generally cause point defects and can even suppress crystallization. This general rule, however, does not apply to colloidal crystals formed by soft microgel particles [Iyer ASJ, Lyon LA (2009) Angew Chem Int Ed 48:4562–4566], as, in this case, the larger particles are able to shrink and join the crystal formed by a majority of smaller particles. Using small-angle X-ray scattering, we find the limit in large-particle concentration for this spontaneous deswelling to persist. We rationalize our data in the context of those counterions that are bound to the microgel particles as a result of the electrostatic attraction exerted by the fixed charges residing on the particle periphery. These bound counterions do not contribute to the suspension osmotic pressure in dilute conditions, as they can be seen as internal degrees of freedom associated with each microgel particle. In contrast, at sufficiently high particle concentrations, the counterion cloud of each particle overlaps with that of its neighbors, allowing these ions to freely explore the space outside the particles. We confirm this scenario by directly measuring the osmotic pressure of the suspension. Because these counterions are then no longer bound, they create an osmotic pressure difference between the inside and outside of the microgels, which, if larger than the microgel bulk modulus, can cause deswelling, explaining why large, soft microgel particles feel the squeeze when suspended with a majority of smaller particles. We perform small-angle neutron scattering measurements to further confirm this remarkable behavior.

  7. Microsparks Generated by Charged Particles in Dielectric Liquids

    Science.gov (United States)

    Geiger, Robert

    2012-10-01

    The electrodynamics of charged particles in dielectric liquids have been described by several authors [1,2]. As a charged particle approaches an electrode of opposite charge the local electric field eventually exceeds the dielectric strength of the liquid and a microspark is generated. These plasmas can be very small, about type of discharge can provide a simple means of generating non-thermal plasmas in dielectric liquids, such as oils or other hydrocarbons, which can be used to chemically process the liquids. Such a technology may lead to a highly efficient method of heavy oil upgrading which can be easily scaled. In order to understand the plasma properties optical emission spectroscopy is carried out for various hydrocarbons and voltage-current characteristics are used to determine the energy cost for this process. [4pt] [1] Melcher, James R. Continuum Electromechanics. Cambridge, MA: MIT Press, 1981.[0pt] [2] Jones, Thomas B. Electromechanics of Particles. Cambridge University Press 1995.[0pt] [3] Staack, D., Fridman, A., Gutsol, A., Gogotsi, Y. and Friedman, G. 2008, Angew. Chem., Int. Ed. 47, 8020.

  8. Visible and Near-Infrared (VNIR) Spectroscopy of Altered Basalts with Application to the ChemCam Library for Mars Science Laboratory

    Science.gov (United States)

    Hadnott, B.; Ehlmann, B. L.

    2012-12-01

    The discovery of Fe, Mg, and Al clays on Mars using VNIR spectroscopy from orbit indicates past low temperature/pressure hydrothermal and weathering environments. Laboratory analysis of Mars-analog rocks from these settings on Earth was used to build the ChemCam sample library for Mars Science Laboratory, permitting for more accurate compositional analysis of Martian samples, improved linkages between VNIR's mineralogic and ChemCam's elemental data, and improved recognition of different environmental settings for aqueous alteration. VNIR spectroscopy was used to analyze 4 suites of altered basaltic rocks—one from San Carlos, AZ and three from various locations in Iceland. Continuum shape and absorption features were found to vary, depending on the environment and extent of alteration. Relatively unaltered rocks had electronic absorptions related to ferrous iron. The strength of the 1.9- μm (μm = microns) H2O absorption correlated with the degree of aqueous alteration. Samples with strong 1.9- μm absorptions often exhibited absorption bands at 1.4, 2.2, and 2.3 μm indicating the presence of clay minerals and/or features at 0.5-0.8 μm indicative of ferric iron oxides. Diagnostic absorption features and continuum slopes have been used to identify a representative subset of rocks from each suite for further analysis for the ChemCam library. Noteworthy spectral features for all suites included variation of absorption bands from 2.0-2.5 μm. Most samples contained an absorption band near 2.21 μm, indicating the presence of Si-OH or Al-OH; a 2.3 μm band is also present in some samples, indicating the presence of Mg-OH and Fe-OH, with subtle shifts between 2.29 and 2.35 μm indicating the major cation and constituent phase (e.g. amorphous phase, smectite or chlorite). Overall continuum slope correlated with the degree of alteration. Flat slopes contained weak 1.9 μm bands (little alteration) and sometimes ferrous iron absorptions of primary minerals. Negative

  9. In situ calibration using univariate analyses based on the onboard ChemCam targets: first prediction of Martian rock and soil compositions

    International Nuclear Information System (INIS)

    Curiosity rover landed on August 6th, 2012 in Gale Crater, Mars and it possesses unique analytical capabilities to investigate the chemistry and mineralogy of the Martian soil. In particular, the LIBS technique is being used for the first time on another planet with the ChemCam instrument, and more than 75,000 spectra have been returned in the first year on Mars. Curiosity carries body-mounted calibration targets specially designed for the ChemCam instrument, some of which are homgeneous glasses and others that are fine-grained glass-ceramics. We present direct calibrations, using these onboard standards to infer elements and element ratios by ratioing relative peak areas. As the laser spot size is around 300 μm, the LIBS technique provides measurements of the silicate glass compositions representing homogeneous material and measurements of the ceramic targets that are comparable to fine-grained rock or soil. The laser energy and the auto-focus are controlled for all sequences used for calibration. The univariate calibration curves present relatively to very good correlation coefficients with low RSDs for major and ratio calibrations. Trace element calibration curves (Li, Sr, and Mn), down to several ppm, can be used as a rapid tool to draw attention to remarkable rocks and soils along the traverse. First comparisons to alpha-particle X-ray spectroscopy (APXS) data, on selected targets, show good agreement for most elements and for Mg# and Al/Si estimates. SiO2 estimates using univariate cannot be yet used. Na2O and K2O estimates are relevant for high alkali contents, but probably under estimated due to the CCCT initial compositions. Very good results for CaO and Al2O3 estimates and satisfactory results for FeO are obtained. - Highlights: • In situ LIBS univariate calibrations are done using the Curiosity onboard standards. • Major and minor element contents can be rapidly obtained. • Trace element contents can be used as a rapid tool along the Martian

  10. Air quality modeling with WRF-Chem v3.5 in East Asia: sensitivity to emissions and evaluation of simulated air quality

    Science.gov (United States)

    Zhong, Min; Saikawa, Eri; Liu, Yang; Naik, Vaishali; Horowitz, Larry W.; Takigawa, Masayuki; Zhao, Yu; Lin, Neng-Huei; Stone, Elizabeth A.

    2016-04-01

    We conducted simulations using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) version 3.5 to study air quality in East Asia at a spatial resolution of 20 km × 20 km. We find large discrepancies between two existing emissions inventories: the Regional Emission Inventory in ASia version 2 (REAS) and the Emissions Database for Global Atmospheric Research version 4.2 (EDGAR) at the provincial level in China, with maximum differences of up to 500 % for CO emissions, 190 % for NO, and 160 % for primary PM10. Such discrepancies in the magnitude and the spatial distribution of emissions for various species lead to a 40-70 % difference in surface PM10 concentrations, 16-20 % in surface O3 mixing ratios, and over 100 % in SO2 and NO2 mixing ratios in the polluted areas of China. WRF-Chem is sensitive to emissions, with the REAS-based simulation reproducing observed concentrations and mixing ratios better than the EDGAR-based simulation for July 2007. We conduct additional model simulations using REAS emissions for January, April, July, and October of 2007 and evaluate simulations with available ground-level observations. The model results illustrate clear regional variations in the seasonal cycle of surface PM10 and O3 over East Asia. The model meets the air quality model performance criteria for both PM10 (mean fractional bias, MFB ⩽ ±60 %) and O3 (MFB ⩽ ±15 %) at most of the observation sites, although the model underestimates PM10 over northeastern China in January. The model predicts the observed SO2 well at sites in Japan, while it tends to overestimate SO2 in China in July and October. The model underestimates observed NO2 in all 4 months. Our study highlights the importance of constraining emissions at the provincial level for regional air quality modeling over East Asia. Our results suggest that future work should focus on the improvement of provincial-level emissions especially estimating primary PM, SO2, and NOx.

  11. Potential sources of nitrous acid (HONO) and their impacts on ozone: A WRF-Chem study in a polluted subtropical region

    Science.gov (United States)

    Zhang, Li; Wang, Tao; Zhang, Qiang; Zheng, Junyu; Xu, Zheng; Lv, Mengyao

    2016-04-01

    Current chemical transport models commonly undersimulate the atmospheric concentration of nitrous acid (HONO), which plays an important role in atmospheric chemistry, due to the lack or inappropriate representations of some sources in the models. In the present study, we parameterized up-to-date HONO sources into a state-of-the-art three-dimensional chemical transport model (Weather Research and Forecasting model coupled with Chemistry: WRF-Chem). These sources included (1) heterogeneous reactions on ground surfaces with the photoenhanced effect on HONO production, (2) photoenhanced reactions on aerosol surfaces, (3) direct vehicle and vessel emissions, (4) potential conversion of NO2 at the ocean surface, and (5) emissions from soil bacteria. The revised WRF-Chem was applied to explore the sources of the high HONO concentrations (0.45-2.71 ppb) observed at a suburban site located within complex land types (with artificial land covers, ocean, and forests) in Hong Kong. With the addition of these sources, the revised model substantially reproduced the observed HONO levels. The heterogeneous conversions of NO2 on ground surfaces dominated HONO sources contributing about 42% to the observed HONO mixing ratios, with emissions from soil bacterial contributing around 29%, followed by the oceanic source (~9%), photochemical formation via NO and OH (~6%), conversion on aerosol surfaces (~3%), and traffic emissions (~2%). The results suggest that HONO sources in suburban areas could be more complex and diverse than those in urban or rural areas and that the bacterial and/or ocean processes need to be considered in HONO production in forested and/or coastal areas. Sensitivity tests showed that the simulated HONO was sensitive to the uptake coefficient of NO2 on the surfaces. Incorporation of the aforementioned HONO sources significantly improved the simulations of ozone, resulting in increases of ground-level ozone concentrations by 6-12% over urban areas in Hong Kong and

  12. Impact of vehicular emissions on the formation of fine particles in the Sao Paulo Metropolitan Area: a numerical study with the WRF-Chem model

    Science.gov (United States)

    Vara-Vela, A.; Andrade, M. F.; Kumar, P.; Ynoue, R. Y.; Muñoz, A. G.

    2016-01-01

    The objective of this work is to evaluate the impact of vehicular emissions on the formation of fine particles (PM2.5; ≤ 2.5 µm in diameter) in the Sao Paulo Metropolitan Area (SPMA) in Brazil, where ethanol is used intensively as a fuel in road vehicles. The Weather Research and Forecasting with Chemistry (WRF-Chem) model, which simulates feedbacks between meteorological variables and chemical species, is used as a photochemical modelling tool to describe the physico-chemical processes leading to the evolution of number and mass size distribution of particles through gas-to-particle conversion. A vehicular emission model based on statistical information of vehicular activity is applied to simulate vehicular emissions over the studied area. The simulation has been performed for a 1-month period (7 August-6 September 2012) to cover the availability of experimental data from the NUANCE-SPS (Narrowing the Uncertainties on Aerosol and Climate Changes in Sao Paulo State) project that aims to characterize emissions of atmospheric aerosols in the SPMA. The availability of experimental measurements of atmospheric aerosols and the application of the WRF-Chem model made it possible to represent some of the most important properties of fine particles in the SPMA such as the mass size distribution and chemical composition, besides allowing us to evaluate its formation potential through the gas-to-particle conversion processes. Results show that the emission of primary gases, mostly from vehicles, led to a production of secondary particles between 20 and 30 % in relation to the total mass concentration of PM2.5 in the downtown SPMA. Each of PM2.5 and primary natural aerosol (dust and sea salt) contributed with 40-50 % of the total PM10 (i.e. those ≤ 10 µm in diameter) concentration. Over 40 % of the formation of fine particles, by mass, was due to the emission of hydrocarbons, mainly aromatics. Furthermore, an increase in the number of small particles impaired the

  13. Inclusion of polar sea-ice emissions and sea-salt aerosol recycling of bromine into the global CAM-Chem chemistry-climate model

    Science.gov (United States)

    Fernandez, Rafael Pedro; Ordoñez, Carlos; Kinnison, Douglas; Lamarque, Jean-Francois; Saiz-Lopez, Alfonso

    2013-04-01

    The global CAM-Chem chemistry climate model has been updated by including a coupled polar module with a full halogen chemistry mechanism and time-varying organic and inorganic halogen emissions into the polar marine boundary layer. The baseline halogen CAM-Chem setup has already been validated for the tropics and mid-latitudes and includes natural sources of very short-lived (VSL) halocarbons from the oceans; reactive chlorine, bromine and iodine species; related photochemical, gas-phase and heterogeneous reactions, as well as wet and dry deposition for relevant species. The coupled polar module considers i) time-dependent sea-ice emissions of Br2 and BrCl as result of recycling over the deposited snow over sea-ice, ii) sea-salt aerosol recycling of BrONO2, BrNO2 and HOBr in the polar boundary layer and iii) improved sea-salt recycling efficiency over fresh sea-ice regions representing the contributions from blowing snow. The external brominated sources posses a 2-fold dependence on both solar zenith angle and local sea-ice cover. The time/sea-ice dependent local Br2 flux was scaled to reproduce observations of reactive bromine species over coastal Antarctica. This results in an Antarctic mean sea-ice flux of ~200 Gg Br yr-1 with maximum emissions in late spring, as a compromise between sea-ice coverage and intensity of radiation. Recycling of bromine over sea-salt aerosol is the dominant factor controlling the tropospheric vertical column density (VCD) of BrO and other inorganic bromine species. A monthly-dependent depletion factor is introduced to account for the net fraction of Br in sea-salt that is released to the atmosphere. Model results have been validated locally against measurements of BrO performed at several Antarctic stations, showing a good agreement both in the boundary layer concentrations for the entire year and the springtime maximum BrO observed in October. The seasonality and intensity of the BrO total and tropospheric columns are also in

  14. In situ calibration using univariate analyses based on the onboard ChemCam targets: first prediction of Martian rock and soil compositions

    Energy Technology Data Exchange (ETDEWEB)

    Fabre, C. [GeoRessources lab, Université de Lorraine, Nancy (France); Cousin, A.; Wiens, R.C. [Los Alamos National Laboratory, Los Alamos, NM (United States); Ollila, A. [University of NM, Albuquerque (United States); Gasnault, O.; Maurice, S. [IRAP, Toulouse (France); Sautter, V. [Museum National d' Histoire Naturelle, Paris (France); Forni, O.; Lasue, J. [IRAP, Toulouse (France); Tokar, R.; Vaniman, D. [Planetary Science Institute, Tucson, AZ (United States); Melikechi, N. [Delaware State University (United States)

    2014-09-01

    Curiosity rover landed on August 6th, 2012 in Gale Crater, Mars and it possesses unique analytical capabilities to investigate the chemistry and mineralogy of the Martian soil. In particular, the LIBS technique is being used for the first time on another planet with the ChemCam instrument, and more than 75,000 spectra have been returned in the first year on Mars. Curiosity carries body-mounted calibration targets specially designed for the ChemCam instrument, some of which are homgeneous glasses and others that are fine-grained glass-ceramics. We present direct calibrations, using these onboard standards to infer elements and element ratios by ratioing relative peak areas. As the laser spot size is around 300 μm, the LIBS technique provides measurements of the silicate glass compositions representing homogeneous material and measurements of the ceramic targets that are comparable to fine-grained rock or soil. The laser energy and the auto-focus are controlled for all sequences used for calibration. The univariate calibration curves present relatively to very good correlation coefficients with low RSDs for major and ratio calibrations. Trace element calibration curves (Li, Sr, and Mn), down to several ppm, can be used as a rapid tool to draw attention to remarkable rocks and soils along the traverse. First comparisons to alpha-particle X-ray spectroscopy (APXS) data, on selected targets, show good agreement for most elements and for Mg# and Al/Si estimates. SiO{sub 2} estimates using univariate cannot be yet used. Na{sub 2}O and K{sub 2}O estimates are relevant for high alkali contents, but probably under estimated due to the CCCT initial compositions. Very good results for CaO and Al{sub 2}O{sub 3} estimates and satisfactory results for FeO are obtained. - Highlights: • In situ LIBS univariate calibrations are done using the Curiosity onboard standards. • Major and minor element contents can be rapidly obtained. • Trace element contents can be used as a

  15. Politiques de non-intégration dans les monarchies du Golfe Non-integration policies in the Gulf monarchies. The reasons behind their longevity

    Directory of Open Access Journals (Sweden)

    Claire Beaugrand

    2010-12-01

    Full Text Available Si la majeure partie des études migratoires sont concentrées sur les migrations dites « Nord-Sud », celles-ci ne constituent pourtant, d’après Peter Sutherland, représentant spécial des Nations Unies pour les migrations, qu’environ la moitié des flux migratoires mondiaux. Malgré les recherches poursuivies par les Ifre, qui notent que « certains pays d’émigration se sont transformés en terre d’immigration », ces migrations « Sud-Sud » restent moins documentées. Un « Sud » est assez particulier, à savoir les pays du Conseil de coopération du Golfe (Ccg, qui, s’ils ne sont ni industrialisés ni ne se qualifient comme appartenant à une région avancée ou développée, comptent parmi les pays les plus riches du monde en termes de PIB per capita. Ce dernier indicateur met au jour deux éléments socio-économiques fondamentaux de la région : d’abord la grande richesse tirée des ressources en hydrocarbures, mais surtout, la population nationale de ces pays, peu nombreuse quand ils ont commencé leur envol économique, est restée proportionnellement faible, malgré les forts besoins en main d’œuvre engendrés par leur développement vertigineux et de leur forte natalité. Aujourd’hui, il ne fait mystère pour personne que dans certains pays du Ccg qui, depuis leur création, sont tous des importateurs nets de main d’œuvre, la présence étrangère l’emporte en nombre sur la population nationale. Cette situation est le résultat de politiques délibérées visant à la non-intégration des populations immigrées. Cette logique de non-intégration défie beaucoup de propositions quasi-axiomatiques des études migratoires, dont le fer de lance a été la sociologie américaine préoccupée par les notions d’assimilation, de diversité ou multiculturalisme découlant d’une immigration considérée comme durable. Même lorsque le centre d’intér��t des études migratoires a été déplacé de

  16. Surface Pressure Dependencies in the Geos-Chem-Adjoint System and the Impact of the GEOS-5 Surface Pressure on CO2 Model Forecast

    Science.gov (United States)

    Lee, Meemong; Weidner, Richard

    2016-01-01

    In the GEOS-Chem Adjoint (GCA) system, the total (wet) surface pressure of the GEOS meteorology is employed as dry surface pressure, ignoring the presence of water vapor. The Jet Propulsion Laboratory (JPL) Carbon Monitoring System (CMS) research team has been evaluating the impact of the above discrepancy on the CO2 model forecast and the CO2 flux inversion. The JPL CMS research utilizes a multi-mission assimilation framework developed by the Multi-Mission Observation Operator (M2O2) research team at JPL extending the GCA system. The GCA-M2O2 framework facilitates mission-generic 3D and 4D-variational assimilations streamlining the interfaces to the satellite data products and prior emission inventories. The GCA-M2O2 framework currently integrates the GCA system version 35h and provides a dry surface pressure setup to allow the CO2 model forecast to be performed with the GEOS-5 surface pressure directly or after converting it to dry surface pressure.

  17. Using cloud resolving WRF-Chem simulations to explore the aerosol impact on numerical weather prediction and evaluate the aerosol aware Grell-Freitas convective parameterization

    Science.gov (United States)

    Grell, Georg; Marrapu, Pallavi; Freitas, Saulo R.; Psckham, Steven E.

    2015-04-01

    A convective parameterization is applied and evaluated that may be used in high resolution non-hydrostatic mesoscale models for weather and air quality prediction, as well as in modeling system with unstructured varying grid resolutions and for convection aware simulations. This scheme is based on a stochastic approach originally implemented by Grell and Devenyi (2002) and described in more detail in Grell and Freitas (2014, ACP). Interactions with aerosols have been implemented through a CCN dependent autoconversion of cloud water to rain as well as an aerosol dependent evaporation of cloud drops. Initial tests with this newly implemented aerosol approach showed plausible results with a decrease in predicted precipitation in some areas, caused by the changed autoconversion mechanism. Here we compare and evaluate performance over a 10-day period using the SAMBBA test case of the Working Group for Numerical Experimentation (WGNE) on aerosol impacts on numerical weather prediction. A shorter period is also compared to fully cloud-resolving simulations using WRF-Chem.

  18. Summertime tropospheric ozone assessment over the Mediterranean region using the thermal infrared IASI/MetOp sounder and the WRF-Chem model

    Directory of Open Access Journals (Sweden)

    S. Safieddine

    2014-05-01

    Full Text Available Over the Mediterranean region, elevated tropospheric ozone (O3 values are recorded, especially in summer. We use the Infrared Atmospheric Sounding Interferometer (IASI and the Weather Research and Forecasting Model with Chemistry (WRF-Chem to understand and interpret the factors and emission sources responsible for the high O3 concentrations observed in the Mediterranean troposphere. Six years of IASI data have been analyzed and show consistent maxima during summer, with an increase of up to 22% in the [0–8] km O3 column in the eastern part of the basin compared to the middle of the basin. We analyze 2010 as an example year to investigate the processes that contribute to these summer maxima. Using two modeled O3 tracers (inflow to the model domain and local anthropogenic emissions, we show that between the surface and 2 km, O3 is mostly formed from anthropogenic emissions and above 4 km, is mostly transported from outside the domain. Evidence of stratosphere to troposphere exchanges (STE in the eastern part of the basin is shown, and corresponds with low relative humidity and high potential vorticity.

  19. Simulation of Surface Ozone Pollution in the Central Gulf Coast Region Using WRF/Chem Model: Sensitivity to PBL and Land Surface Physics

    Directory of Open Access Journals (Sweden)

    Anjaneyulu Yerramilli

    2010-01-01

    Full Text Available The fully coupled WRF/Chem (Weather Research and Forecasting/Chemistry model is used to simulate air quality in the Mississippi Gulf coastal region at a high resolution (4 km for a moderately severe summer ozone episode between 18 CST 7 and 18 CST 10 June 2006. The model sensitivity is studied for meteorological and gaseous criteria pollutants (O3, NO2 using three Planetary Boundary Layer (PBL and four land surface model (LSM schemes and comparison of model results with monitoring station observations. Results indicated that a few combinations of PBL and LSMs could reasonably produce realistic meteorological fields and that the combination of Yonsei University (YSU PBL and NOAH LSM provides best predictions for winds, temperature, humidity and mixed layer depth in the study region for the period of study. The diurnal range in ozone concentration is better estimated by the YSU PBL in association with either 5-layer or NOAH land surface model. The model seems to underestimate the ozone concentrations in the study domain because of underestimation of temperatures and overestimation of winds. The underestimation of NO2 by model suggests the necessity of examining the emission data in respect of its accurate representation at model resolution. Quantitative analysis for most monitoring stations indicates that the combination of YSU PBL with NOAH LSM provides the best results for various chemical species with minimum BIAS, RMSE, and high correlation values.

  20. Comment on “A model for phosphate glass topology considering the modifying ion sub-network” [J. Chem. Phys. 140, 154501 (2014)

    Energy Technology Data Exchange (ETDEWEB)

    Sidebottom, David L., E-mail: sidebottom@creighton.edu [Physics Department, Creighton University, 2500 California Plaza, Omaha, Nebraska 68178 (United States)

    2015-03-14

    In a recent paper, Hermansen, Mauro, and Yue [J. Chem. Phys. 140, 154501 (2014)] applied the temperature-dependent constraint theory to model both the glass transition temperature, T{sub g}, and fragility, m, of a series of binary alkali phosphate glasses of the form (R{sub 2}O){sub x}(P{sub 2}O{sub 5}){sub 1−x}, where R represents an alkali species. Key to their success seems to be the retention of linear constraints between the alkali ion (R{sup +}) and the non-bridging oxygens near T{sub g}, which allows the model to mimic a supposed minimum for both T{sub g}(x) and m(x) located near x = 0.2. However, the authors have overlooked several recent studies that clearly show there is no minimum in m(x). We argue that the retention of the alkali ion constraints at these temperatures is unjustified and question whether the model calculations can be revised to meet the actual experimental data. We also discuss alternative interpretations for the fragility based on two-state thermodynamics that can accurately account for its compositional dependence.

  1. Impact of anthropogenic aerosols on summer precipitation in the Beijing-Tianjin-Hebei urban agglomeration in China: Regional climate modeling using WRF-Chem

    Science.gov (United States)

    Wang, Jun; Feng, Jinming; Wu, Qizhong; Yan, Zhongwei

    2016-06-01

    The WRF model with chemistry (WRF-Chem) was employed to simulate the impacts of anthropogenic aerosols on summer precipitation over the Beijing-Tianjin-Hebei urban agglomeration in China. With the aid of a high-resolution gridded inventory of anthropogenic emissions of trace gases and aerosols, we conducted relatively long-term regional simulations, considering direct, semi-direct and indirect effects of the aerosols. Comparing the results of sensitivity experiments with and without emissions, it was found that anthropogenic aerosols tended to enhance summer precipitation over the metropolitan areas. Domain-averaged rainfall was increased throughout the day, except for the time around noon. Aerosols shifted the precipitation probability distribution from light or moderate to extreme rain. Further analysis showed that the anthropogenic aerosol radiative forcing had a cooling effect at the land surface, but a warming effect in the atmosphere. However, enhanced convective strength and updrafts accompanied by water vapor increases and cyclone-like wind shear anomalies were found in the urban areas. These responses may originate from cloud microphysical effects of aerosols on convection, which were identified as the primary cause for the summer rainfall enhancement.

  2. Chem-Prep PZT 95/5 for Neutron Generator Applications: Particle Size Distribution Comparison of Development and Production-Scale Powders

    International Nuclear Information System (INIS)

    The Materials Chemistry Department 1846 has developed a lab-scale chem-prep process for the synthesis of PNZT 95/5, a ferroelectric material that is used in neutron generator power supplies. This process (Sandia Process, or SP) has been successfully transferred to and scaled by Department 14192 (Ceramics and Glass Department), (Transferred Sandia Process, or TSP), to meet the future supply needs of Sandia for its neutron generator production responsibilities. In going from the development-size SP batch (1.6 kg/batch) to the production-scale TSP powder batch size (10 kg/batch), it was important that it be determined if the scaling process caused any ''performance-critical'' changes in the PNZT 95/5 being produced. One area where a difference was found was in the particle size distributions of the calcined PNZT powders. Documented in this SAND report are the results of an experimental study to determine the origin of the differences in the particle size distribution of the SP and TSP powders

  3. Application of a coupled ecosystem-chemical equilibrium model, DayCent-Chem, to stream and soil chemistry in a Rocky Mountain watershed

    Science.gov (United States)

    Hartman, M.D.; Baron, J.S.; Ojima, D.S.

    2007-01-01

    Atmospheric deposition of sulfur and nitrogen species have the potential to acidify terrestrial and aquatic ecosystems, but nitrate and ammonium are also critical nutrients for plant and microbial productivity. Both the ecological response and the hydrochemical response to atmospheric deposition are of interest to regulatory and land management agencies. We developed a non-spatial biogeochemical model to simulate soil and surface water chemistry by linking the daily version of the CENTURY ecosystem model (DayCent) with a low temperature aqueous geochemical model, PHREEQC. The coupled model, DayCent-Chem, simulates the daily dynamics of plant production, soil organic matter, cation exchange, mineral weathering, elution, stream discharge, and solute concentrations in soil water and stream flow. By aerially weighting the contributions of separate bedrock/talus and tundra simulations, the model was able to replicate the measured seasonal and annual stream chemistry for most solutes for Andrews Creek in Loch Vale watershed, Rocky Mountain National Park. Simulated soil chemistry, net primary production, live biomass, and soil organic matter for forest and tundra matched well with measurements. This model is appropriate for accurately describing ecosystem and surface water chemical response to atmospheric deposition and climate change. ?? 2006 Elsevier B.V. All rights reserved.

  4. In vivo identical reversibility of rad-bio-chem lesions in blood, bone marrow, liver, endocrine system and on the whole body

    International Nuclear Information System (INIS)

    The fundamental scientific researches of a new patented pharmaceutical product STANOSIMAGNE, was initiated, directed and developed since 1995, as interdisciplinary challenge for in vivo decorporation on natural way of radio-toxic uranium (235U) and radionuclides, and the treatment of lesions induced by radiation injury, or heavy metals. The synergic effect - decorporation and reversibility - for in vivo identical reversibility of rad-bio-chem lesions in blood, bone marrow, liver, endocrine system, derma and vital organs verifies and sustains the scientific discovery. The safety and efficiency of clinical administration of the medicine STANOSIMAGNE capsules and ointment is based on the non-clinic (pre-clinic) practical pharmacological research on 635 standard laboratory animals regarding the absence of any kind of toxicity. The pharmacology researches have been carried out, along with medical, pharmaceutical and biochemical didactic specialists, coming from the Laboratories Departments of Pharmacology, Phytochemistry, Biochemistry, Chemistry and Pharmaceutical Technique of the University of Medicine and Pharmacy 'Carol Davila', Bucharest. The treatment of the persons exposed to irradiation or heavy metals contamination, in risk areas, and the continuation of the pilot clinical studies on several cases, that could not be solved by regular medical methods and treatments, are in accordance with the Directive 2001/20/CE, of the Parliament of the European Union, which implement the norms of good practice, in clinical studies.(author)

  5. Assessing the Impact of Climate Change on Land-Water-Ecosystem Quality in Polar and Mountainous Regions: A New Interregional Project (INT5153)

    International Nuclear Information System (INIS)

    The INT5153 project aims to improve the understanding of the impact of climate change on fragile polar and mountainous ecosystems on both a local and global scale for their better management and conservation. Seven core and five related benchmark sites have been selected from different global regions for specific assessments of the impact of climate change with the following expected outcomes and outputs: Outcomes: • Improved understanding of the impact of climate change on the cryosphere in polar and mountainous ecosystems and its effects on landwater- ecosystem quality at both local and global scales. • Recommendations for improvement of regional policies for soil and agricultural water management, conservation, and environmental protection in polar and mountainous regions. Outputs: • Specific strategies to minimize the adverse effects of, and adapt to, reduced seasonal snow and glacier covered areas on land-water-ecosystem quality in polar and mountain regions across the world. • Enhanced interregional network of laboratories and institutions competent in the assessment of climate change impacts on the cryosphere and land-water-ecosystem quality, using isotopic and nuclear techniques. • Increased number of young scientists trained in the use of isotope and nuclear techniques to assess the impact of climate change on the cryosphere and land-water-ecosystem quality in polar and mountainous ecosystems. • Platform/database with global access for continuing work and monitoring of impact of climate change on fragile polar and mountainous ecosystems at local and global scales, as well as for communicating findings to policy makers and communities. • Improved understanding of the effects of climate change disseminated through appropriate publications, policy briefs, and through a dedicated internet platform. • Methodologies and protocols for investigations in specific ecosystems and conservation/adaptation measures for agriculture areas

  6. Construire ses cartes : le développement d’outils statistiques interactifs intégrés à un SIG

    Directory of Open Access Journals (Sweden)

    Benoît Ogier

    1999-06-01

    Full Text Available Les systèmes d’exploitation des micro-ordinateurs proposent aujourd’hui des interfaces conviviales. En outre, certains micro-SIG offrent des possibilités intéressantes de développement par l’intermédiaire de " plug ins ", dans les langages de programmation les plus courants (Pascal, C, Delphi.... C’est sur ces bases que nous avons pu compléter les fonctionnalités d’un micro-SIG (requêtes spatiales, calcul d’itinéraire, gestion de données, cartographie..., par une série de modules statistiques et graphiques.Ces outils mettent à la disposition de l’utilisateur, toutes les informations statistiques et représentations, nécessaires à une analyse complète des données. En effet, les modules sont liés entre eux, ce qui permet d’aborder une étude sous plusieurs angles simultanément, et de comparer les résultats de différentes méthodes. De plus, une mise a jour automatique de la carte s’effectue dès que l’on procède à une mise en classe à l’aide d’un des modules. On est donc en présence d’une complète interactivité SIG-Cartes-Statistiques.Mais on peut aller plus loin et envisager l’expérimentation d’autres outils graphiques, notamment pour l’exploitation des résultats d’analyses factorielles.

  7. Le développement des compétences informationnelles et son intégration disciplinaire dans un programme EPEP à l’heure des TIC

    Directory of Open Access Journals (Sweden)

    Sylvie Viola

    2007-01-01

    Full Text Available [Français] L’article suivant vise à faire partager l’expérience qui a été menée auprès des étudiants de premier cycle universitaire relativement à l’élaboration et à la mise en place d’un programme de formation sur les compétences informationnelles. Aussi, dans un premier temps, nous présenterons les résultats obtenus par des étudiants-maîtres à un sondage sur les compétences informationnelles. Dans un deuxième temps, nous décrirons le programme de formation des compétences informationnelles, ses différentes étapes de développement ainsi que les principales activités de formation qui ont été intégrées au sein du programme de baccalauréat en éducation préscolaire et en enseignement primaire. Finalement, nous en analyserons brièvement les principales retombées pédagogiques ainsi que les limites et les avantages. [English] This article concerns the development and implementation of a competency-based program aimed at developing data processing skills within a preservice elementary teacher education program. We will first present the results of the survey conducted with elementary student teachers concerning their computer skills. Following this will be a description of the program designed to develop these skills. We will then present the different stages of the program-building process, the main curriculum activities incorporated into the program, and the implementation activities within the elementary education curriculum. Lastly, we will briefly discuss the advantages and limitations of the implemented program, giving priority to its implication for the preservice elementary teacher curriculum.

  8. Fracture numérique, fracture sociale : aux frontières de l'intégration et de l'exclusion

    Directory of Open Access Journals (Sweden)

    Luc Vodoz

    2010-12-01

    Full Text Available La fracture numérique est une ligne de rupture symbolique, le tracé d'un clivage entre d'une part les individus ou groupes sociaux qui sont – ou se sentent – bien intégrés à la « société de l'information », d'autre part ceux qui sont – ou se sentent – exclus de cette société. Comme bien d'autres frontières, cette ligne est difficilement visible voire totalement imperceptible dans le terrain. Ce texte relate un cheminement sur la frontière, sur les logiques prévalant à l'articulation entre deux espaces, entre deux réalités comme entre deux points de vue. Il s’efforce de comprendre ce que vivent celles et ceux qui se situent sur la limite, qui tentent de la franchir ou au contraire d'éviter leur expulsion. L’investigation s’est déroulée dans les milieux de la formation professionnelle et continue en matière de TIC. Plus largement, il s'agissait d'examiner les éventuelles correspondances entre intégration à (ou exclusion de la « société de l'information » d'une part, et d'autre part l'intégration (ou l'exclusion sociale plus générale des personnes considérées.Digital gap, social gap: sitting on the boundaries of integration and exclusionThe digital gap is a symbolic demarcation of rupture, a line that traces the separation between individuals or social groups who are – or feel they are –integrated into the “information society”, and those who are – or feel – excluded from this society. As with many other boundaries, this particular line is difficult to perceive or even is totally imperceptible in the field. Analysing a journey on the boundary itself, this text concentrates on the logics emerging from the connection between the two spaces, two realities, two points of view. It attempts to understand what those who find themselves on this limit actually live, as do also those who attempt de jump the gap or on the contrary try to avoid their expulsion. The enquiry took place in a

  9. Modélisation des paramètres d’une batterie Plomb-Acide, et son intégration dans un système photovoltaïque autonome

    OpenAIRE

    BENCHERIF, MOHAMMED

    2015-01-01

    La modélisation des mécanismes physico-chimique se déroulant à l’intérieur d’une batterie sont d’une complexité telle que plusieurs approches s’affrontent pour minimiser cette complexité et prédire le plus fidèlement l’état de charge au temps t dans les conditions d’utilisation de la batterie et en prenant en compte leur effets de vieillissement. Dans cette étude, nous limiterons notre modélisation à une batterie plomb-acide intégré à un système photovoltaïque autonome. La conn...

  10. Quelle est l'évolution des meilleures pratiques et le développement des instruments de couverture du risque de taux d'intérêts à court-terme ?

    OpenAIRE

    Kurti, Astrit; Sahut, Jean-Michel

    2014-01-01

    Ce travail a pour but d’étudier le risque de taux d’intérêt et la gestion de celui-ci au sein d’une banque de premier ordre. Avec la collaboration de divers employés d’une grande banque suisse, ce travail ressortira les pratiques courantes et leurs évolutions concernant les instruments de couverture du risque de taux d’intérêt à court terme. D’une part, il y aura la gestion de ce risque vis-à-vis de la banque elle-même et, d’autre part, les solutions offertes aux clients, « grandes entreprise...

  11. Aire Marine Protégée, intérêt général environnemental et territoire, un rendez-vous manqué ? Le cas de Mayotte

    OpenAIRE

    Cadoret, Anne; Beuret, Jean-Eudes

    2016-01-01

    Le Parc Naturel Marin de Mayotte a été créé en janvier 2010 à l’issue d’un processus rapide. Répondant à un intérêt général environnemental, comment cette initiative nationale s’est-elle ancrée dans le territoire, autour de la construction d’un projet de développement durable territorial et de la territorialisation de l’intérêt général moteur du projet ? Qu'est-ce qui fonde l’acceptabilité sociale du projet ? L’analyse du processus de construction du projet, puis des controverses mises en ava...

  12. Les modèles de chaînes logistiques intégrant le Coût de la qualité et les outils d'optimisation:Revue de littérature

    OpenAIRE

    douiri, lamiae; Jabri, A.; EL BARKANY, Abdellah

    2015-01-01

    Dans cet article, nous envisageons de faire une revue de littérature sur les modèles modernes intégrant le coût de la qualité (CoQ) distingués en quatre catégories, à savoir les modèles PAF ou modèles de Crosby, les modèles basés sur les coûts d'opportunité, les modèles basés sur les coûts de process et l'approche ABC. Dans une seconde partie, nous présenterons un comparatif des modèles de conception des chaînes logistiques (SCND )intégrant le CoQ en fonction de la catégorie du modèle, object...

  13. Développement d’un modèle pour la détermination du champ magnétique impulsionnel induit à l’intérieur d’un bâtiment foudroyé.

    OpenAIRE

    Miry, C.; Amador, E.; Duquerroy, P.; Bachelier, E.; Prost, D.; Issac, F.; Grange, F.; Journet, S.

    2014-01-01

    L'objectif de cette étude est de déterminer un modèle équivalent permettant de reproduire correctement le comportement d'un bâtiment en béton armé lorsque celui-ci est frappé par la foudre. Nous nous intéressons à l'évaluation du champ magnétique à l'intérieur du bâtiment. Des mesures sont présentées et utilisées afin de comparer les modèles numériques proposés. Différentes méthodes de calcul sont confrontées.

  14. Aide à la décision pour l'intégration de la sécurité au plus tôt en phase de conception : approche innovante de reconception de machines agricoles

    OpenAIRE

    Sadeghi, Leyla

    2014-01-01

    Les travaux de recherche exposés dans ce mémoire se positionnent dans le domaine de la conception sécuritaire. Cette thèse s’intéresse plus particulièrement à rendre opérationnelle la méthode IRAD (Innovative Risk Assessment Design), qui intègre la sécurité de manière systématique tout au long du processus de conception. Dans cet objectif, nous proposons dans un premier temps de formaliser un type de retour d’expérience (les rapports d’accident) qui détaille les faits liés aux éléments d’une ...

  15. InteMech机构分析与仿真系统总体开发技术%Design Technology in the Development of the Software of Analysis and Simulation for Mechanism

    Institute of Scientific and Technical Information of China (English)

    宗志坚; 高群; 陈立平; 陈新度

    2004-01-01

    选择具有自主版权的几何建模平台INTESOLID开发了机构分析与仿真系统.从系统的需求分析、总体设计以及应用流程设计等方面做了全面阐述.最终实现了完全自主版权的CAD与机构分析集成系统.%A series of development has been introduced in the article, including function design, logic model design, object system design as well as class design. A general software named InteMech has been developed based on the work and geometric platform so-called InteCAD. In this way, by integrating the geometric model, topologic model and calculation model together, the software can be used for calculation of kinemics and kinostatics as well as animation and interference test.

  16. Tourisme et intégration euro-méditerranéenne : quel rôle pour les firmes touristiques dans l'évolution du tourisme au Maghreb ?

    OpenAIRE

    Weigert, Maxime

    2013-01-01

    Ce travail doctoral, mené dans le cadre d'une recherche-action pour l'Institut de prospective économique du monde méditerranéen, s'inscrit dans les études sur la régionalisation euro-méditerranéenne. L'une des caractéristiques de l'intégration des régions Nord-Sud est le rôle central que les firmes multinationales, en tant qu'entités spatiales, tiennent dans le processus. Les travaux sur l'intégration nord-américaine (Alena) et asiatique (zone Asean + 3) révèlent que l'intensification des éch...

  17. Méthodologie d'analyse en vue de l'amélioration des interférences électromagnétiques dans les systèmes intégrés RF

    OpenAIRE

    DUPOUX, Céline

    2011-01-01

    Les travaux présentés dans ce mémoire proposent une méthodologie d'étude des interférences électromagnétiques dans les systèmes intégrés RF. Cette thèse se focalise sur les problèmes de couplage rayonné en champ proche entre différentes parties d'une puce électronique ou entre circuits intégrés d'une carte. Ensuite cette méthodologie est appliquée sur deux cas d'études à différentes échelles, dans le premier cas l'étude du couplage entre un amplificateur de puissance 3G et un transceiver e...

  18. Les contradictions de la gestion intégrée des déchets urbains : l'incinération entre valorisation énergétique et refus social

    OpenAIRE

    Rocher, Laurence

    2008-01-01

    L'article vise, à partir de l'exemple de l'incinération, à mettre en évidence les logiques de convergence et de divergence entre différentes composantes d'une gestion intégrée des déchets. Les dimensions technique et territoriale de l'intégration sont abordées à travers les notions de valorisation (récupération des matières et de l'énergie) et de proximité (traitement des résidus au plus près de leur production), qui structurent la politique française de gestion des déchets, tout en répondant...

  19. Orientations stratégiques pour la GIZC (Gestion intégrée des zones côtières) en baie de Seine : Catalogage des données et organisation de l'information

    OpenAIRE

    Bourcier, Alban; Deprez, Samuel

    2007-01-01

    Sont présentés ici les principaux résultats d'une étude exploratoire menée en collaboration avec la Ville du Havre et l'Agence d'urbanisme de la région havraise dans le cadre d'un appel à projet de la DIACT ayant trait à la Gestion intégrée des zones côtières (GIZC). L'objectif de cette étude était de démontrer l'intérêt de la géomatique (traitement informatique des données géographiques) comme support de management territorial par la mise en place opérationnelle d'un outil de catalogage des ...

  20. Les conditions d'efficacité et d'inefficacité de l'intégration d'élèves en situation de handicap, à l'école primaire: point de vue d'enseignants

    OpenAIRE

    Michaud, Nadia; Doudin, Pierre-André

    2015-01-01

    L'intégration scolaire est un sujet très sensible auprès des enseignants. En effet, les réticences pour accueillir un élève en situation de handicap dans les classes peuvent être nombreuses. D’un point de vue légal, l’Accord Intercantonal sur la collaboration dans le domaine de la pédagogie spécialisée a vu le jour en janvier 2011. Il incite les cantons à préférer les solutions intégratives aux solutions séparatives. On tend ainsi de plus en plus vers le concept de « l’école pour tous ». La p...

  1. Aurélie Choné, Rudolf Steiner, Carl Gustav Jung, Hermann Hesse, passeurs entre Orient et Occident. Intégration et transformation des savoirs sur l’Orient dans l’espace germanophone (1890-1940)

    OpenAIRE

    Michon, Bruno

    2012-01-01

    La publication de la thèse d’Aurélie Choné intéressera à la fois le germaniste, l’historien des idées et le sociologue des religions. L’auteur, germaniste de formation, propose un voyage dans l’Allemagne du début du xxe siècle, à la rencontre de trois auteurs, Rudolf Steiner, Carl Gustav Jung et Hermann Hesse. Elle s’interroge sur l’intégration et la transformation des savoirs sur l’Orient dans chacune de leurs œuvres. La comparaison entre leurs trois domaines de prédilection, respectivement ...

  2. Etude experimentale et théorique des intéractions non-covalentes en chimie organométallique : le concept d'hémichélation

    OpenAIRE

    Werlé, Christophe

    2014-01-01

    The present manuscript will present a rational method of synthesis, characterization, determination of the electronic structure and dynamic behaviour of solution-persistent, and formally unsaturated binuclear Cr(0)-M complexes (with M= Pd(II), Pt(II) or Rh(I)). This new class of complexes constitutes rare examples of persistent coordinatively unsaturated 14-electrons complexes, whose cohesion stems essentially from a compensation of insufficient donor/acceptor Cr-M bonding by non-covalent int...

  3. Átmenet a mezőgazdaságban - agrárgazdaságtan átmenetben. MTA Közgazdaságtudományi Intézet, Budapest, 2004. november 7-8.

    OpenAIRE

    B., B.; F., Sz.

    2005-01-01

    Az MTA Közgazdaságtudományi Intézet alapításának 50. évfordulójához kapcsolódó konferenciasorozat egyik rendezvénye az Átmenet a mezőgazdaságban - agrárgazdaságtan átmenetben (Transition in Agriculture - Agricultural Economics in Transition) című nemzetközi konferencia volt.

  4. PubChem atom environments

    OpenAIRE

    Hähnke, Volker D; Bolton, Evan E.; Bryant, Stephen H.

    2015-01-01

    Background Atom environments and fragments find wide-spread use in chemical information and cheminformatics. They are the basis of prediction models, an integral part in similarity searching, and employed in structure search techniques. Most of these methods were developed and evaluated on the relatively small sets of chemical structures available at the time. An analysis of fragment distributions representative of most known chemical structures was published in the 1970s using the Chemical A...

  5. WRF/Chem study of dry and wet deposition of trifluoroacetic acid produced from the atmospheric degradation of a few short-lived HFCs

    Science.gov (United States)

    Kazil, J.; McKeen, S. A.; Kim, S.; Ahmadov, R.; Grell, G. A.; Talukdar, R. K.; Ravishankara, A. R.

    2011-12-01

    HFC-134a (1,1,1,2-tetrafluoroethane) is the prevalent (used in >80% passenger cars and commercial vehicles worldwide) refrigerant in automobile air conditioning units (MACs). With an atmospheric lifetime of ~14 years and a global warming potential (GWP) of 1430 on a 100-year time horizon, HFC-134a does not meet current and expected requirements for MAC refrigerants in many parts of the world. Therefore, substitutes with lower GWP are being sought. One of the simplest way to achieve lower GWP is to use chemicals with shorter atmospheric lifetimes. In this work, we investigate the dry and wet deposition and the rainwater concentration of trifluoroacetic acid (TFA) produced by the atmospheric oxidation of 2,3,3,3-tetrafluoropropene (TFP) and 1,2,3,3,3-pentafluoropropene (PFP). The WRF/Chem model was used to calculate dry and wet TFA deposition over the contiguous USA during the May-September 2006 period that would result from replacing HFC-134a in MACs with a 1:1 molar ratio mixture of 2,3,3,3-tetrafluoropropene (TFP) and 1,2,3,3,3-pentafluoropropene (PFP). The simulation is evaluated by comparing observations of precipitation and sulfate wet deposition at stations of the National Atmospheric Deposition Program (NADP). Simulated precipitation and sulfate wet deposition correlate well with the observations, but exhibit a positive bias for precipitation and a negative bias for sulfate wet deposition. Atmospheric lifetimes of TFP and PFP against oxidation by the hydroxyl radical OH, a prognostic species in WRF/Chem, are ~5 and ~4 days in the simulation, respectively. The model setup allows the attribution of dry and wet TFA deposition to individual source regions (California, Houston, Chicago, and the remaining contiguous USA in this work). TFA deposition is highest in the eastern USA because of numerous large sources and high precipitation in the region. West of the Continental Divide, TFA deposition is significantly lower, and its origin is dominated by emissions from

  6. Application of WRF/Chem-MADRID and WRF/Polyphemus in Europe – Part 1: Model description, evaluation of meteorological predictions, and aerosol–meteorology interactions

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2013-07-01

    Full Text Available Comprehensive model evaluation and comparison of two 3-D air quality modeling systems (i.e., the Weather Research and Forecast model (WRF/Polyphemus and WRF with chemistry and the Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution (MADRID (WRF/Chem-MADRID are conducted over Western Europe. Part 1 describes the background information for the model comparison and simulation design, the application of WRF for January and July 2001 over triple-nested domains in Western Europe at three horizontal grid resolutions: 0.5°, 0.125°, and 0.025°, and the effect of aerosol/meteorology interactions on meteorological predictions. Nine simulated meteorological variables (i.e., downward shortwave and longwave radiation fluxes (SWDOWN and LWDOWN, outgoing longwave radiation flux (OLR, temperature at 2 m (T2, specific humidity at 2 m (Q2, relative humidity at 2 m (RH2, wind speed at 10 m (WS10, wind direction at 10 m (WD10, and precipitation (Precip are evaluated using available observations in terms of spatial distribution, domainwide daily and site-specific hourly variations, and domainwide performance statistics. The vertical profiles of temperature, dew points, and wind speed/direction are also evaluated using sounding data. WRF demonstrates its capability in capturing diurnal/seasonal variations and spatial gradients and vertical profiles of major meteorological variables. While the domainwide performance of LWDOWN, OLR, T2, Q2, and RH2 at all three grid resolutions is satisfactory overall, large positive or negative biases occur in SWDOWN, WS10, and Precip even at 0.125° or 0.025° in both months and in WD10 in January. In addition, discrepancies between simulations and observations exist in T2, Q2, WS10, and Precip at mountain/high altitude sites and large urban center sites in both months, in particular, during snow events or thunderstorms. These results indicate the model's difficulty in capturing meteorological variables in complex

  7. Quantifying sources of elemental carbon over the Guanzhong Basin of China: A consistent network of measurements and WRF-Chem modeling.

    Science.gov (United States)

    Li, Nan; He, Qingyang; Tie, Xuexi; Cao, Junji; Liu, Suixin; Wang, Qiyuan; Li, Guohui; Huang, Rujin; Zhang, Qiang

    2016-07-01

    We conducted a year-long WRF-Chem (Weather Research and Forecasting Chemical) model simulation of elemental carbon (EC) aerosol and compared the modeling results to the surface EC measurements in the Guanzhong (GZ) Basin of China. The main goals of this study were to quantify the individual contributions of different EC sources to EC pollution, and to find the major cause of the EC pollution in this region. The EC measurements were simultaneously conducted at 10 urban, rural, and background sites over the GZ Basin from May 2013 to April 2014, and provided a good base against which to evaluate model simulation. The model evaluation showed that the calculated annual mean EC concentration was 5.1 μgC m(-3), which was consistent with the observed value of 5.3 μgC m(-3). Moreover, the model result also reproduced the magnitude of measured EC in all seasons (regression slope = 0.98-1.03), as well as the spatial and temporal variations (r = 0.55-0.78). We conducted several sensitivity studies to quantify the individual contributions of EC sources to EC pollution. The sensitivity simulations showed that the local and outside sources contributed about 60% and 40% to the annual mean EC concentration, respectively, implying that local sources were the major EC pollution contributors in the GZ Basin. Among the local sources, residential sources contributed the most, followed by industry and transportation sources. A further analysis suggested that a 50% reduction of industry or transportation emissions only caused a 6% decrease in the annual mean EC concentration, while a 50% reduction of residential emissions reduced the winter surface EC concentration by up to 25%. In respect to the serious air pollution problems (including EC pollution) in the GZ Basin, our findings can provide an insightful view on local air pollution control strategies. PMID:27064614

  8. Benchmarking of AREVA BWR FDIC-PEZOG model against first BFE3 cycle 15 application of On-Line NobleChem results

    International Nuclear Information System (INIS)

    The combination of AREVA's BWR FDIC-PEZOG tools allows the calculation of the total liftoff as a measure of fuel performance and a risk indicator for fuel reliability. The AREVA BWR FDIC tool is a crud modeling tool. The PEZOG tool models the platinum-enhanced zirconium oxide growth of fuel cladding when exposed to platinum during operation. Continuous effort to improve these tools used for the total liftoff calculations is illustrated by the benchmarking of the tools after the application of On-Line NobleChemTM at TVA Browns Ferry Unit 3 during Cycle 15. A set of runs using the modified FDIC-PEZOG model and actual plant water chemistry for Cycle 15 and partial data for Cycle 16 were performed. The updated results' deposit thickness and deposit composition predictions for EOC15 were compared to the measured data from EOC15 and are presented in this paper. The updated predicted deposit thickness matched the actual, measured value exactly. Predicted deposit composition near the fuel rod boundary, nearer to the bulk reactor water, and as an averaged deposit, as presented in the paper, compared extremely well with the measured data at EOC15. The updated AREVA methodology resulted in lower fuel oxide thickness predictions over the life of the fuel as compared to the initial evaluations for BFE3 by incorporating more recent experimental data on the thermal conductivity of zirconia; unnecessary conservatism in the prediction of the fuel oxide thickness over the life of the fuel was removed in the improved model. (authors)

  9. Retrievals of formaldehyde from ground-based FTIR and MAX-DOAS observations at the Jungfraujoch station and comparisons with GEOS-Chem and IMAGES model simulations

    Science.gov (United States)

    Franco, B.; Hendrick, F.; Van Roozendael, M.; Müller, J.-F.; Stavrakou, T.; Marais, E. A.; Bovy, B.; Bader, W.; Fayt, C.; Hermans, C.; Lejeune, B.; Pinardi, G.; Servais, C.; Mahieu, E.

    2015-04-01

    As an ubiquitous product of the oxidation of many volatile organic compounds (VOCs), formaldehyde (HCHO) plays a key role as a short-lived and reactive intermediate in the atmospheric photo-oxidation pathways leading to the formation of tropospheric ozone and secondary organic aerosols. In this study, HCHO profiles have been successfully retrieved from ground-based Fourier transform infrared (FTIR) solar spectra and UV-visible Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) scans recorded during the July 2010-December 2012 time period at the Jungfraujoch station (Swiss Alps, 46.5° N, 8.0° E, 3580 m a.s.l.). Analysis of the retrieved products has revealed different vertical sensitivity between both remote sensing techniques. Furthermore, HCHO amounts simulated by two state-of-the-art chemical transport models (CTMs), GEOS-Chem and IMAGES v2, have been compared to FTIR total columns and MAX-DOAS 3.6-8 km partial columns, accounting for the respective vertical resolution of each ground-based instrument. Using the CTM outputs as the intermediate, FTIR and MAX-DOAS retrievals have shown consistent seasonal modulations of HCHO throughout the investigated period, characterized by summertime maximum and wintertime minimum. Such comparisons have also highlighted that FTIR and MAX-DOAS provide complementary products for the HCHO retrieval above the Jungfraujoch station. Finally, tests have revealed that the updated IR parameters from the HITRAN 2012 database have a cumulative effect and significantly decrease the retrieved HCHO columns with respect to the use of the HITRAN 2008 compilation.

  10. Simulating Dry Deposition Fluxes of PM10 and Particulate Inorganic Nitrogen over the Eastern China Seas During a Severe Asian Dust Event Using WRF-Chem Model

    Institute of Scientific and Technical Information of China (English)

    YAN Han; GAO Huiwang; YAO Xiaohong; WANG Zifa

    2012-01-01

    A WRF-Chem model including a comprehensive gas-phase nitrogen chemistry module was used to simulate a severe dust event appearing in the eastern China on 19-25 March,2002.The modeling result well reproduced PM10 concentrations in various distances from the dust sources and the transport pathway of the dust strom.The results showed that both the concentrations and the dry deposition fluxes of PM10 increased over the China seas during the dust event following the passage of a cold front system.The maximum fluxes of PM10 in the Yellow Sea and the East China Sea during the dust event were 5.5 and 8.4 times of those before the event,respectively.However,the temporal variations of the dry deposition fluxes of particulate inorganic nitrogen differed over the Yellow Sea from those over the East China Sea.Nitrate and ammonium in the whole northern China rapidly decreased because of the intrusion of dust-loaded air on 19 March.The dust plume arrived in the Yellow Sea on 20 March,decreasing the particulate inorganic nitrogen in mass concentration accordingly.The minimum dry deposition fluxes of nitrate and ammonium in the Yellow Sea were about 3/5 and 1/6 of those before the dust arrival,respectively.In contrast,when the dust plume crossed over the Yangtze Delta area,it became abundant in nitrate and ammonium and increased the concentrations and dry deposition fluxes of particulate inorganic nitrogen over the East China Sea,where the maximum dry deposition fluxes of nitrate and ammonium increased approximately by 4.1 and 2.6 times of those prior to the dust arrival.

  11. A WRF-Chem Flash Rate Parameterization Scheme and LNOx Analysis of the 29-30 May 2012 Convective Event in Oklahoma During DC3

    Science.gov (United States)

    Cummings, Kristin A.; Pickering, Kenneth E.; Barth, M.; Weinheimer, A.; Bela, M.; Li, Y.; Allen, D.; Bruning, E.; MacGorman, D.; Rutledge, S.; Fuchs, B.; Pollack, I.; Ryerson, T.; Huntrieser, H.

    2014-01-01

    The Deep Convective Clouds and Chemistry (DC3) field campaign in 2012 provided a plethora of aircraft and ground-based observations (e.g., trace gases, lightning and radar) to study deep convective storms, their convective transport of trace gases, and associated lightning occurrence and production of nitrogen oxides (NOx). Based on the measurements taken of the 29-30 May 2012 Oklahoma thunderstorm, an analysis against a Weather Research and Forecasting Chemistry (WRF-Chem) model simulation of the same event at 3-km horizontal resolution was performed. One of the main objectives was to include various flash rate parameterization schemes (FRPSs) in the model and identify which scheme(s) best captured the flash rates observed by the National Lightning Detection Network (NLDN) and Oklahoma Lightning Mapping Array (LMA). The comparison indicates how well the schemes predicted the timing, location, and number of lightning flashes. The FRPSs implemented in the model were based on the simulated thunderstorms physical features, such as maximum vertical velocity, cloud top height, and updraft volume. Adjustment factors were applied to each FRPS to best capture the observed flash trend and a sensitivity study was performed to compare the range in model-simulated lightning-generated nitrogen oxides (LNOx) generated by each FRPS over the storms lifetime. Based on the best FRPS, model-simulated LNOx was compared against aircraft measured NOx. The trace gas analysis, along with the increased detail in the model specification of the vertical distribution of lightning flashes as suggested by the LMA data, provide guidance in determining the scenario of NO production per intracloud and cloud-to-ground flash that best matches the NOx mixing ratios observed by the aircraft.

  12. A Wrf-Chem Flash Rate Parameterization Scheme and LNO(x) Analysis of the 29-30 May 2012 Convective Event in Oklahoma During DC3

    Science.gov (United States)

    Cummings, Kristin A.; Pickering, Kenneth E.; Barth, M.; Weinheimer, A.; Bela, M.; Li, Y.; Allen, D.; Bruning, E.; MacGorman, D.; Rutledge, S.; Fuchs, B.; Pollack, I.; Ryerson, T.; Huntrieser, H.

    2014-01-01

    The Deep Convective Clouds and Chemistry (DC3) field campaign in 2012 provided a plethora of aircraft and ground-based observations (e.g., trace gases, lightning and radar) to study deep convective storms, their convective transport of trace gases, and associated lightning occurrence and production of nitrogen oxides (NOx). Based on the measurements taken of the 29-30 May 2012 Oklahoma thunderstorm, an analysis against a Weather Research and Forecasting Chemistry (WRF-Chem) model simulation of the same event at 3-km horizontal resolution was performed. One of the main objectives was to include various flash rate parameterization schemes (FRPSs) in the model and identify which scheme(s) best captured the flash rates observed by the National Lightning Detection Network (NLDN) and Oklahoma Lightning Mapping Array (LMA). The comparison indicates how well the schemes predicted the timing, location, and number of lightning flashes. The FRPSs implemented in the model were based on the simulated thunderstorms physical features, such as maximum vertical velocity, cloud top height, and updraft volume. Adjustment factors were added to each FRPS to best capture the observed flash trend and a sensitivity study was performed to compare the range in model-simulated lightning-generated nitrogen oxides (LNOx) generated by each FRPS over the storms lifetime. Based on the best FRPS, model-simulated LNOx was compared against aircraft measured NOx. The trace gas analysis, along with the increased detail in the model specification of the vertical distribution of lightning flashes as suggested by the LMA data, provide guidance in determining the scenario of NO production per intracloud and cloud-to-ground flash that best matches the NOx mixing ratios observed by the aircraft.

  13. The response of the equatorial tropospheric ozone to the Madden–Julian Oscillation in TES satellite observations and CAM-chem model simulation

    Directory of Open Access Journals (Sweden)

    W. Sun

    2014-06-01

    Full Text Available The Madden–Julian Oscillation (MJO is the dominant form of the atmospheric intra-seasonal oscillation, manifested by slow eastward movement (about 5 m s−1 of tropical deep convection. This study investigates the MJO's impact on equatorial tropospheric ozone (10° N–10° S in satellite observations and chemical transport model (CTM simulations. For the satellite observations, we analyze the Tropospheric Emission Spectrometer (TES level-2 ozone profile data for the period of January 2004 to June 2009. For the CTM simulations, we run the Community Atmosphere Model with chemistry (CAM-chem driven by the GOES-5 analyzed meteorological fields for the same data period as the TES measurements. Our analysis indicates that the behavior of the Total Tropospheric Column (TTC ozone at the intraseasonal time scale is different from that of the total column ozone, with the signal in the equatorial region comparable with that in the subtropics. The model simulated and satellite measured ozone anomalies agree in their general pattern and amplitude when examined in the vertical cross section (the average spatial correlation coefficient among the 8 phases is 0.63, with an eastward propagation signature at a similar phase speed as the convective anomalies (5 m s−1. The ozone anomalies on the intraseasonal time scale are about five times larger when lightning emissions of NOx are included in the simulation than when they are not. Nevertheless, large-scale advection is the primary driving force for the ozone anomalies associated with the MJO. The variability related to the MJO for ozone reaches up to 47% of the total variability (ranging from daily to interannual, indicating the MJO should be accounted for in simulating ozone perturbations in the tropics.

  14. What is driving changes in long-range transport of dust from Africa to the Americas? A 30 year synthesis of the GEOS-Chem model and observations

    Science.gov (United States)

    Ridley, D. A.; Heald, C. L.

    2012-12-01

    The Sahara and Sahelian regions produce approximately half of the world's dust emissions, resulting in significant radiative effects, air quality issues and mineral deposition, not only in Africa, but across the Atlantic and in the Americas. Determining how these impacts may change in the future requires a thorough understanding of the processes controlling emission, transport and deposition of dust. Long-term records of dust concentration measured in the Caribbean have, until the nineties, correlated with Sahelian precipitation and climatic indicators, potentially providing ways to predict changes in dust. However, this relationship is no longer clear and there are significant changes in the seasonality of dust transported to the Americas currently with no obvious explanation. We use the GEOS-Chem global chemical transport model with NASA GMAO meteorological re-analyses (MERRA) to simulate the 30 year period 1979 - 2008. A synthesis of observations from multiple satellite and surface-based platforms is used to evaluate the model, primarily in terms of its ability to simulate the long-range transport of mineral dust from Africa. We then investigate what drives the changes in long-range transport of African dust to the Americas over diurnal to decadal timescales. This enables understanding of the relative importance of the individual processes controlling these changes, and the sensitivity of air quality and dust deposition downwind. This work aims to determine 1) how sensitive air quality and dust deposition in the Americas is to changes in African dust emissions, 2) the role of meteorological variables affecting the inter-annual variability of dust emission and deposition, and 3) the impact that land use changes and desertification in the Sahel may have in terms of the influence on dust transported to the Americas.

  15. DECADE web portal: toward the integration of MaGa, EarthChem and VOTW data systems to further the knowledge on Earth degassing

    Science.gov (United States)

    Cardellini, Carlo; Frigeri, Alessandro; Lehnert, Kerstin; Ash, Jason; McCormick, Brendan; Chiodini, Giovanni; Fischer, Tobias; Cottrell, Elizabeth

    2015-04-01

    The release of volatiles from the Earth's interior takes place in both volcanic and non-volcanic areas of the planet. The comprehension of such complex process and the improvement of the current estimates of global carbon emissions, will greatly benefit from the integration of geochemical, petrological and volcanological data. At present, major online data repositories relevant to studies of degassing are not linked and interoperable. In the framework of the Deep Earth Carbon Degassing (DECADE) initiative of the Deep Carbon Observatory (DCO), we are developing interoperability between three data systems that will make their data accessible via the DECADE portal: (1) the Smithsonian Institutionian's Global Volcanism Program database (VOTW) of volcanic activity data, (2) EarthChem databases for geochemical and geochronological data of rocks and melt inclusions, and (3) the MaGa database (Mapping Gas emissions) which contains compositional and flux data of gases released at volcanic and non-volcanic degassing sites. The DECADE web portal will create a powerful search engine of these databases from a single entry point and will return comprehensive multi-component datasets. A user will be able, for example, to obtain data relating to compositions of emitted gases, compositions and age of the erupted products and coincident activity, of a specific volcano. This level of capability requires a complete synergy between the databases, including availability of standard-based web services (WMS, WFS) at all data systems. Data and metadata can thus be extracted from each system without interfering with each database's local schema or being replicated to achieve integration at the DECADE web portal. The DECADE portal will enable new synoptic perspectives on the Earth degassing process allowing to explore Earth degassing related datasets over previously unexplored spatial or temporal ranges.

  16. Procédé intégré de traitement du gaz naturel Integrated Process for Natural Gas Treatment

    Directory of Open Access Journals (Sweden)

    Larue J.

    2006-11-01

    Full Text Available L'Institut français du pétrole a développé une nouvelle technique de traitement du gaz naturel, le procédé intégré IFPEXOL, basé sur une nouvelle mise en oeuvre de méthanol à basse température, qui incorpore dans un procédé unique les trois fonctions de déshydratation, extraction des liquides de gaz naturel (LGN et désacidification. Le procédé IFPEXOL se compose de deux sections successives : une première section IFPEX-1 de déshydratation et d'extraction des LGN, une deuxième section IFPEX-2 de désacidification si nécessaire. Pour chaque section, l'influence des paramètres principaux sur les performances du procédé est examinée. Après un programme de recherche et développement au laboratoire et sur une unité pilote, le procédé IFPEXOL a été industrialisé. La première unité IFPEX-1 a démarré en juin 1992 au Canada sur le champ d'East Gilby en association avec Petro-Canada; par la suite, 11 autres unités IFPEX-1, dont 7 sont en opération, ont été vendues. La section IFPEX-2 est en cours de commercialisation. The Institut français du pétrole has developed a new natural gas treatment technique, the integrated IFPEXOL process, based on the use of methanol at low temperature, and which includes 3 functions in only one step : dehydration, NGL recovery and acid gases removal. The IFPEXOL process is split into two successive sections : IFPEX-1 removes NGL and water, IFPEX-2 removes the acid gases when necessary. For each section, the influence of the main parameters on the process performances is examined. After a research and development program at laboratory scale and on a pilot plant, the IFPEXOL process has reached the industrial step. The first IFPEX-1 unit has started up in June 1992 in Canada at Petro-Canada's East Gilby field. Subsequently, 11 other units, of which 7 are running, have been licenced. The results obtained from the industrial plants confirm the simulation models. The IFPEX-2 section is in

  17. Fundamental and Applied Bioorganometallic Chemistry of Technetium and Rhenium

    International Nuclear Information System (INIS)

    Site directed accumulation is the base for therapy and imaging with inorganic medicinal compounds. To match selectively the structural properties of receptors, the topology of targeting complexes must be flexible and easily adaptable. For in vivo application, kinetic stability is desirable and in an advanced design, the complex itself can become part of the structure to be recognized by the receptor (3D structural space occupation concept).1 To match these requirements, we introduced the fac-{99mTcI(CO)3}+ building block many years ago. Many different complexes with this core were subjected to targeting studies and the organometallic chemistry of Tc developed rapidly beyond designs for molecular imaging. Some prominent examples will give insight into their structures and activities for molecular imaging. For complementing the fac-{99mTcI(CO)3}+ tag, we switched from low- to high-valent complexes. The isolobal fac-{99mTcVII(O)3}+ building block was introduced.2 Preparation of TcVII complexes is an example about how research is translated to routinely applicable conditions. For proceeding towards theranostics, homologous complexes with Re for therapy and with 99mTc complexes for imaging are mandatory. A new synthetic approach enabled the preparation of cyclopentadienyl complexes of both elements and based on pharmaceutically active lead structures.3 Newly introduced bis-arene complexes scopes at using these structures in analogy to ferrocene.4 The presentation exemplifies how questions from, ultimately practical, application lead to basic developments. Unexpected results in turn influence the discovery of new imaging and therapeutic agents.5 (1) Meggers, E. Curr. Opin. Chem. Biol. 2007, 11, 287. (2) Braband, H.; Tooyama, Y.; Fox, T.; Alberto, R. Chem. Eur. J. 2009, 15, 633. (3) Can, D.; Spingler, B.; Schmutz, P.; Mendes, F.; Raposinho, P.; Fernandes, C.; Carta, F.; Innocenti, A.; Santos, I.; Supuran, C. T.; Alberto, R. Angew. Chem. Int. Edit. 2012, 51, 3354. (4) Benz

  18. Proton Donor/acceptor Propensities of Ammonia: Rotational Studies of its Molecular Complexes with Organic Molecules

    Science.gov (United States)

    Giuliano, Barbara M.; Maris, Assimo; Melandri, Sonia; Favero, Laura B.; Evangelisti, Luca; Caminati, Walther

    2009-06-01

    We studied the rotational spectra of the adducts of ammonia with several organic molecules, namely tert-butanol, glycidol, ethyl alcohol, anisol and 1,4-difluorobenzene. The adducts with glycidol and ethanol have been observed for both conformers of the substrate molecule. Based on the rotational and ^{14}N quadrupole coupling constants of the various complexes, we found a considerably different behaviour of ammonia, with respect to water, in its proton donor/acceptor double role. In the interaction with the three alcohol molecules, NH_{3} acts as a proton acceptor and the OH groups as a proton donor. However, in the case of glycidol-NH_{3}, a secundary N-H\\cdotsO interaction occurrs between ammonia and the ether oxygen. This interaction generates a sizable V_{3} barrier to the internal rotation of the NH_{3} moiety, while NH_{3} undergoes a free rotation in tert-butanol-NH_{3} and in ethanol-NH_{3}. As to the anisole-NH_{3} and 1,4-difluorobenzene-NH_{3} complexes, the NH_{3} group explicits its double proton donor/acceptor role, although through two weak (C_{Me}-H\\cdotsN and N-H\\cdotsπ) H-bonds. There is, however, an important difference between the two complexes, because in the first one NH_{3} lies out of the aromatic plane, while in the second one it is in the plane of the aromatic ring. B. M. Giuliano, M. C. Castrovilli, A. Maris, S. Melandri, W. Caminati and E. A. Cohen, Chem.Phys.Lett., 2008, 463, 330 B. M. Giuliano, S. Melandri, A. Maris, L. B. Favero and W. Caminati, Angew.Chem.Int.Ed., 2009, 48, 1102

  19. An Unusual Co(I)-H Interaction: Structural and Mechanistic Ramifications for Methyltransferases

    Science.gov (United States)

    Kumar, Manoj

    2014-03-01

    The cob(II)alamin cob(I)alamin (Co2+/Co1+) reduction is a common chemical event in a broad family of cytoplasmic methyltransferases and ATP:corrinoid adenosyltransferases, respectively. Despite its broad and general chemical appeal, the Co2+/Co1+ reduction continues to remain one of the least understood aspects of corrinoid chemistry. This is due in part to the inaccessible redox chemistry of Co2+/Co1+ couple under cellular conditions i.e., the reduction potential of cob(II)alamin (-500 mV vs SHE) is more negative than that of the common physiological reductants (-280 mV to -440 mV vs SHE) present in the cellular environments. To gain better understanding about the Co2+/Co1+ reduction, we have utilized the density functional theory and quantum mechanics/molecular mechanics (QM/MM) computational methods. The calculations indicate that cob(I)alamin, a ubiquitous B12 intermediate, is not square planar as has been commonly accepted, but a square pyramidal species due to the unusual hydrogen bonding interaction between the Co1+ ion and its axial ligands (Angew. Chem. Int. Ed. 2011, 50, 8702-8705; Inorg. Chem.2012, 51, 5533-5538). The Co1+-H interaction exerts an anodic shift of 100 mV vs SHE upon the reduction potential of the Co2+/Co1+ couple, which explains why this redox process is observed inside transferases. Building upon these new insights, an alternate mechanism for the enzyme-bound Co2+/Co1+ redox process is suggested that is mediated by the square pyramidal cob(I)alamin rather than its commonly accepted square planar analogue.

  20. Analysis of the Eyjafjallajökull Eruption using the WRF-Chem Model compared to Satellite-Based Ash Retrieval Algorithms

    Science.gov (United States)

    Steensen, T. S.; Stuefer, M.; Webley, P.; Grell, G. A.; de Freitas, S. R.

    2010-12-01

    On April 14th, 2010, the long-dormant ice-capped volcano Eyjafjallajökull in southern Iceland exhibited a black ash-rich plume that quickly developed into an upper-tropospheric ash-cloud covering large parts of Europe grounding the majority of European air traffic for days. The emission of the ash-cloud continued for three days before the eruption turned more magmatic on April 18th. Due to a strong jet stream the plume initially drifted towards the United Kingdom and Norway with ash-fall occurring in many cities in both countries. Over the course of a week, most countries in Europe were affected by the dispersing cloud resulting in numbers of closed airports never seen before, grounded planes and confused passengers. This eruption, although small on the international scale, drew volcanic hazards into the public eye and called for better understanding of evolving volcanic plumes and their ash content. The Weather Research and Forecast model (WRF) coupled with Chemistry (Chem) has been utilized to use wind fields and chemical compositions to forecast the drift and chemical alteration of dispersed substances such as forest fires and volcanic ash and, in this study, was used to simulate the developing plume in time, based on physical input parameters of the initial plume as well as the wind patterns over Europe during April 2010. The results of this model have been compared to satellite-based ash retrieval algorithms like the Reverse Absorption Method and the Principal Component Analysis using Advanced Very High Resolution Radiometer (AVHRR) the Moderate-Resolution Imaging Spectroradiometer (MODIS) data. This comparison allows both, the ratification of the model as a forecasting tool and of the satellites as an in-situ measurement. Both parts are essential components to be able to predict and analyze airborne volcanic ash and to constantly improve the hazard assessment of ash cloud forecasting to minimize the burden on the aviation community while maximizing the