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...

"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…

Early Warning: Brought to you by the DoD Chem-Bio Defense Program

Science.gov (United States)

Security Robots Lasers RSS Feed Early Warning: Brought to you by the DoD Chem-Bio Defense Program help warfighters prevent, protect against, respond to or recover from chem-bio threats and effects . Hassell said he and his team don't monitor the world for chem-bio threats, they develop the tools that

3D-e-Chem-VM: Structural Cheminformatics Research Infrastructure in a Freely Available Virtual Machine

NARCIS (Netherlands)

McGuire, R.; Verhoeven, S.; Vass, M.; Vriend, G.; Esch, I.J. de; Lusher, S.J.; Leurs, R.; Ridder, L.; Kooistra, A.J.; Ritschel, T.; Graaf, C. de

2017-01-01

3D-e-Chem-VM is an open source, freely available Virtual Machine ( http://3d-e-chem.github.io/3D-e-Chem-VM/ ) that integrates cheminformatics and bioinformatics tools for the analysis of protein-ligand interaction data. 3D-e-Chem-VM consists of software libraries, and database and workflow tools

3D-e-Chem-VM : Structural Cheminformatics Research Infrastructure in a Freely Available Virtual Machine

NARCIS (Netherlands)

McGuire, Ross; Verhoeven, Stefan; Vass, Márton; Vriend, Gerrit; De Esch, Iwan J P; Lusher, Scott J.; Leurs, Rob; Ridder, Lars; Kooistra, Albert J.; Ritschel, Tina; de Graaf, C.

2017-01-01

3D-e-Chem-VM is an open source, freely available Virtual Machine ( http://3d-e-chem.github.io/3D-e-Chem-VM/ ) that integrates cheminformatics and bioinformatics tools for the analysis of protein-ligand interaction data. 3D-e-Chem-VM consists of software libraries, and database and workflow tools

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)

ChemAND - a system health monitor for plant chemistry

International Nuclear Information System (INIS)

Turner, C.W.; Mitchell, G.R.; Tosello, G.; Balakrishnan, P.V.; McKay, G.; Thompson, M.; Dundar, Y.; Bergeron, M.; Laporte, R.

2001-01-01

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)

ChemAND - a system health monitor for plant chemistry

International Nuclear Information System (INIS)

Turner, C.W.; Mitchel, G.R.; Tosello, G.; Balakrishnan, P.V.; McKay, G.; Thompson, M.; Dundar, Y.; Bergeron, M.; Laporte, R.

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)

Chem/bio sensing with non-classical light and integrated photonics.

Science.gov (United States)

Haas, J; Schwartz, M; Rengstl, U; Jetter, M; Michler, P; Mizaikoff, B

2018-01-29

Modern quantum technology currently experiences extensive advances in applicability in communications, cryptography, computing, metrology and lithography. Harnessing this technology platform for chem/bio sensing scenarios is an appealing opportunity enabling ultra-sensitive detection schemes. This is further facilliated by the progress in fabrication, miniaturization and integration of visible and infrared quantum photonics. Especially, the combination of efficient single-photon sources together with waveguiding/sensing structures, serving as active optical transducer, as well as advanced detector materials is promising integrated quantum photonic chem/bio sensors. Besides the intrinsic molecular selectivity and non-destructive character of visible and infrared light based sensing schemes, chem/bio sensors taking advantage of non-classical light sources promise sensitivities beyond the standard quantum limit. In the present review, recent achievements towards on-chip chem/bio quantum photonic sensing platforms based on N00N states are discussed along with appropriate recognition chemistries, facilitating the detection of relevant (bio)analytes at ultra-trace concentration levels. After evaluating recent developments in this field, a perspective for a potentially promising sensor testbed is discussed for reaching integrated quantum sensing with two fiber-coupled GaAs chips together with semiconductor quantum dots serving as single-photon sources.

Distributed chemical computing using ChemStar: an open source java remote method invocation architecture applied to large scale molecular data from PubChem.

Science.gov (United States)

Karthikeyan, M; Krishnan, S; Pandey, Anil Kumar; Bender, Andreas; Tropsha, Alexander

2008-04-01

We present the application of a Java remote method invocation (RMI) based open source architecture to distributed chemical computing. This architecture was previously employed for distributed data harvesting of chemical information from the Internet via the Google application programming interface (API; ChemXtreme). Due to its open source character and its flexibility, the underlying server/client framework can be quickly adopted to virtually every computational task that can be parallelized. Here, we present the server/client communication framework as well as an application to distributed computing of chemical properties on a large scale (currently the size of PubChem; about 18 million compounds), using both the Marvin toolkit as well as the open source JOELib package. As an application, for this set of compounds, the agreement of log P and TPSA between the packages was compared. Outliers were found to be mostly non-druglike compounds and differences could usually be explained by differences in the underlying algorithms. ChemStar is the first open source distributed chemical computing environment built on Java RMI, which is also easily adaptable to user demands due to its "plug-in architecture". The complete source codes as well as calculated properties along with links to PubChem resources are available on the Internet via a graphical user interface at http://moltable.ncl.res.in/chemstar/.

Consequences of ChemR23 heteromerization with the chemokine receptors CXCR4 and CCR7.

Science.gov (United States)

de Poorter, Cédric; Baertsoen, Kevin; Lannoy, Vincent; Parmentier, Marc; Springael, Jean-Yves

2013-01-01

Recent studies have shown that heteromerization of the chemokine receptors CCR2, CCR5 and CXCR4 is associated to negative binding cooperativity. In the present study, we build on these previous results, and investigate the consequences of chemokine receptor heteromerization with ChemR23, the receptor of chemerin, a leukocyte chemoattractant protein structurally unrelated to chemokines. We show, using BRET and HTRF assays, that ChemR23 forms homomers, and provide data suggesting that ChemR23 also forms heteromers with the chemokine receptors CCR7 and CXCR4. As previously described for other chemokine receptor heteromers, negative binding cooperativity was detected between ChemR23 and chemokine receptors, i.e. the ligands of one receptor competed for the binding of a specific tracer of the other. We also showed, using mouse bone marrow-derived dendritic cells prepared from wild-type and ChemR23 knockout mice, that ChemR23-specific ligands cross-inhibited CXCL12 binding on CXCR4 in a ChemR23-dependent manner, supporting the relevance of the ChemR23/CXCR4 interaction in native leukocytes. Finally, and in contrast to the situation encountered for other previously characterized CXCR4 heteromers, we showed that the CXCR4-specific antagonist AMD3100 did not cross-inhibit chemerin binding in cells co-expressing ChemR23 and CXCR4, demonstrating that cross-regulation by AMD3100 depends on the nature of receptor partners with which CXCR4 is co-expressed.

First order mean field games - explicit solutions, perturbations and connection with classical mechanics

KAUST Repository

Gomes, Diogo A.

2016-01-06

We present recent developments in the theory of first-order mean-field games (MFGs). A standard assumption in MFGs is that the cost function of the agents is monotone in the density of the distribution. This assumption leads to a comprehensive existence theory and to the uniqueness of smooth solutions. Here, our goals are to understand the role of local monotonicity in the small perturbation regime and the properties of solutions for problems without monotonicity. Under a local monotonicity assumption, we show that small perturbations of MFGs have unique smooth solutions. In addition, we explore the connection between first-order MFGs and classical mechanics and KAM theory. Next, for non-monotone problems, we construct non-unique explicit solutions for a broad class of first-order mean-field games. We provide an alternative formulation of MFGs in terms of a new current variable. These examples illustrate two new phenomena: the non-uniqueness of solutions and the breakdown of regularity.

First order mean field games - explicit solutions, perturbations and connection with classical mechanics

KAUST Repository

Gomes, Diogo A.; Nurbekyan, Levon; Prazeres, Mariana

2016-01-01

We present recent developments in the theory of first-order mean-field games (MFGs). A standard assumption in MFGs is that the cost function of the agents is monotone in the density of the distribution. This assumption leads to a comprehensive existence theory and to the uniqueness of smooth solutions. Here, our goals are to understand the role of local monotonicity in the small perturbation regime and the properties of solutions for problems without monotonicity. Under a local monotonicity assumption, we show that small perturbations of MFGs have unique smooth solutions. In addition, we explore the connection between first-order MFGs and classical mechanics and KAM theory. Next, for non-monotone problems, we construct non-unique explicit solutions for a broad class of first-order mean-field games. We provide an alternative formulation of MFGs in terms of a new current variable. These examples illustrate two new phenomena: the non-uniqueness of solutions and the breakdown of regularity.

ChemTS: an efficient python library for de novo molecular generation

Science.gov (United States)

Yang, Xiufeng; Zhang, Jinzhe; Yoshizoe, Kazuki; Terayama, Kei; Tsuda, Koji

2017-12-01

Automatic design of organic materials requires black-box optimization in a vast chemical space. In conventional molecular design algorithms, a molecule is built as a combination of predetermined fragments. Recently, deep neural network models such as variational autoencoders and recurrent neural networks (RNNs) are shown to be effective in de novo design of molecules without any predetermined fragments. This paper presents a novel Python library ChemTS that explores the chemical space by combining Monte Carlo tree search and an RNN. In a benchmarking problem of optimizing the octanol-water partition coefficient and synthesizability, our algorithm showed superior efficiency in finding high-scoring molecules. ChemTS is available at https://github.com/tsudalab/ChemTS.

Consequences of ChemR23 heteromerization with the chemokine receptors CXCR4 and CCR7.

Directory of Open Access Journals (Sweden)

Cédric de Poorter

Full Text Available Recent studies have shown that heteromerization of the chemokine receptors CCR2, CCR5 and CXCR4 is associated to negative binding cooperativity. In the present study, we build on these previous results, and investigate the consequences of chemokine receptor heteromerization with ChemR23, the receptor of chemerin, a leukocyte chemoattractant protein structurally unrelated to chemokines. We show, using BRET and HTRF assays, that ChemR23 forms homomers, and provide data suggesting that ChemR23 also forms heteromers with the chemokine receptors CCR7 and CXCR4. As previously described for other chemokine receptor heteromers, negative binding cooperativity was detected between ChemR23 and chemokine receptors, i.e. the ligands of one receptor competed for the binding of a specific tracer of the other. We also showed, using mouse bone marrow-derived dendritic cells prepared from wild-type and ChemR23 knockout mice, that ChemR23-specific ligands cross-inhibited CXCL12 binding on CXCR4 in a ChemR23-dependent manner, supporting the relevance of the ChemR23/CXCR4 interaction in native leukocytes. Finally, and in contrast to the situation encountered for other previously characterized CXCR4 heteromers, we showed that the CXCR4-specific antagonist AMD3100 did not cross-inhibit chemerin binding in cells co-expressing ChemR23 and CXCR4, demonstrating that cross-regulation by AMD3100 depends on the nature of receptor partners with which CXCR4 is co-expressed.

76 FR 61330 - Endangered and Threatened Wildlife and Plants; Endangered Status and Designation of Critical...

Science.gov (United States)

2011-10-04

... legally precluded from relying on the incremental-effects approach. New Mexico Cattle Growers Ass'n v... above the baseline is permissible under the Act (Arizona Cattle Growers Ass'n v. Salazar, 606 F.3d 1160... further reaffirmed its conclusion in Home Builders Ass'n of Northern California v. U.S. Fish & Wildlife...

FastChem: An ultra-fast equilibrium chemistry

Science.gov (United States)

Kitzmann, Daniel; Stock, Joachim

2018-04-01

FastChem is an equilibrium chemistry code that calculates the chemical composition of the gas phase for given temperatures and pressures. Written in C++, it is based on a semi-analytic approach, and is optimized for extremely fast and accurate calculations.

The PubChem chemical structure sketcher

Directory of Open Access Journals (Sweden)

Ihlenfeldt Wolf D

2009-12-01

Full Text Available Abstract PubChem is an important public, Web-based information source for chemical and bioactivity information. In order to provide convenient structure search methods on compounds stored in this database, one mandatory component is a Web-based drawing tool for interactive sketching of chemical query structures. Web-enabled chemical structure sketchers are not new, being in existence for years; however, solutions available rely on complex technology like Java applets or platform-dependent plug-ins. Due to general policy and support incident rate considerations, Java-based or platform-specific sketchers cannot be deployed as a part of public NCBI Web services. Our solution: a chemical structure sketching tool based exclusively on CGI server processing, client-side JavaScript functions, and image sequence streaming. The PubChem structure editor does not require the presence of any specific runtime support libraries or browser configurations on the client. It is completely platform-independent and verified to work on all major Web browsers, including older ones without support for Web2.0 JavaScript objects.

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 measu...

77 FR 75543 - Representation Procedures and Rulemaking Authority

Science.gov (United States)

2012-12-21

... Ass'n v. Ruckelshaus, 486 F.2d 375, 394 (D.C. Cir. 1973) (``[C]omments must be significant enough to... from a merger involving a carrier or carriers covered by the RLA. Air Line Employees Ass'n, Int'l v... parties to the dispute must request the Board's services in resolving it. Railway Labor Executives' Ass'n...

Displacement Convexity for First-Order Mean-Field Games

KAUST Repository

Seneci, Tommaso

2018-05-01

In this thesis, we consider the planning problem for first-order mean-field games (MFG). These games degenerate into optimal transport when there is no coupling between players. Our aim is to extend the concept of displacement convexity from optimal transport to MFGs. This extension gives new estimates for solutions of MFGs. First, we introduce the Monge-Kantorovich problem and examine related results on rearrangement maps. Next, we present the concept of displacement convexity. Then, we derive first-order MFGs, which are given by a system of a Hamilton-Jacobi equation coupled with a transport equation. Finally, we identify a large class of functions, that depend on solutions of MFGs, which are convex in time. Among these, we find several norms. This convexity gives bounds for the density of solutions of the planning problem.

Explicit Solutions for One-Dimensional Mean-Field Games

KAUST Repository

Prazeres, Mariana

2017-04-05

In this thesis, we consider stationary one-dimensional mean-field games (MFGs) with or without congestion. Our aim is to understand the qualitative features of these games through the analysis of explicit solutions. We are particularly interested in MFGs with a nonmonotonic behavior, which corresponds to situations where agents tend to aggregate. First, we derive the MFG equations from control theory. Then, we compute explicit solutions using the current formulation and examine their behavior. Finally, we represent the solutions and analyze the results. This thesis main contributions are the following: First, we develop the current method to solve MFG explicitly. Second, we analyze in detail non-monotonic MFGs and discover new phenomena: non-uniqueness, discontinuous solutions, empty regions and unhappiness traps. Finally, we address several regularization procedures and examine the stability of MFGs.

78 FR 57604 - Endangered and Threatened Wildlife and Plants; Proposed Endangered Status for Gunnison Sage...

Science.gov (United States)

2013-09-19

... Ariz. Cattle Growers' Ass'n. v. Salazar, 606 F.3d 116, (9th Cir. 2010) cert. denied, 179 L. Ed. 2d 300, 2011 U.S. LEXIS 1362, 79 U.S.L.W. 3475 (2011); Home Builders Ass'n of N. Cal. v. United States Fish... incremental economic impacts imposed by designating critical habitat. (See New Mexico Cattle Growers Ass'n v...

76 FR 26609 - Revisions to the California State Implementation Plan, San Joaquin Valley Unified Air Pollution...

Science.gov (United States)

2011-05-09

... Shipping Ass'n v. Goldstene, 517 F.3d 1108 (9th Cir. 2008), by noting that the regulations in those cases..., EMA v. EPA and Pacific Merchant Shipping Ass'n v. Goldstene, 2009 U.S. Dist Lexis 55516, 70 ERC 1337.... Rd. & Transp. Builders Ass'n v. EPA, 588 F.3d 1109 (DC Cir. 2009), petition for cert. denied, No. 09...

78 FR 5745 - Nonsubstantive, Editorial or Conforming Amendments of the Commission's Rules

Science.gov (United States)

2013-01-28

... conform to judicial decision. See United States Telecom Ass'n v. FCC, 290 F.3d 415, 428-29 (2002...) (redesignated as Sec. 51.319(a)(1)(ii)), to conform to judicial decision. See United States Telecom Ass'n v. FCC... decision. See United States Telecom Ass'n v. FCC, 290 F.3d 415, 428-29 (2002). This Order amends Sec. 51...

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...... properties. In addition, the user has the possibility to search by compound, target, pathway, disease and clinical effect. Genetic variations associated to target proteins were integrated, making it possible to plan pharmacogenetic studies and to suggest human response variability to drug. Finally...

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.

I:\\AA-TYPESET\\CHEM\\2005\\Van Es.vp

African Journals Online (AJOL)

NJD

aDepartment of Biochemistry and Microbiology, Cook College, Rutgers The State University of New Jersey, 08903-0231, USA. .... 4 formation is expected to transfer to the more basic nitrogen of ...... Jouannetaud, French Patent (2000). Chem.

PubChem atom environments.

Science.gov (United States)

Hähnke, Volker D; Bolton, Evan E; Bryant, Stephen H

2015-01-01

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 Abstracts Service data system. More recently, advances in automated synthesis of chemicals allow millions of chemicals to be synthesized by a single organization. In addition, open chemical databases are readily available containing tens of millions of chemical structures from a multitude of data sources, including chemical vendors, patents, and the scientific literature, making it possible for scientists to readily access most known chemical structures. With this availability of information, one can now address interesting questions, such as: what chemical fragments are known today? How do these fragments compare to earlier studies? How unique are chemical fragments found in chemical structures? For our analysis, after hydrogen suppression, atoms were characterized by atomic number, formal charge, implicit hydrogen count, explicit degree (number of neighbors), valence (bond order sum), and aromaticity. Bonds were differentiated as single, double, triple or aromatic bonds. Atom environments were created in a circular manner focused on a central atom with radii from 0 (atom types) up to 3 (representative of ECFP_6 fragments). In total, combining atom types and atom environments that include up to three spheres of nearest neighbors, our investigation identified 28,462,319 unique fragments in the 46 million structures found in the PubChem Compound database as of January 2013. We could identify several factors inflating the number of environments involving transition metals, with many

Chem systems

International Nuclear Information System (INIS)

Anon.

1992-01-01

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%

75 FR 58293 - Promoting a Competitive Market for Capacity Reassignment

Science.gov (United States)

2010-09-24

...), order on reh'g, 119 FERC ] 61,062 (2007). \\30\\ See Interstate Nat'l Gas Ass'n of America v. FERC, 285 F... without requiring market power analyses from each reseller. \\41\\ Interstate Nat'l Gas Ass'n of American v. FERC, 285 F.3d at 33 (DC Cir. 2002). \\42\\ Interstate Nat'l Gas Ass'n of America v. FERC, 285 F.3d 18 at...

NutriChem 2.0: exploring the effect of plant-based foods on human health and drug efficacy

DEFF Research Database (Denmark)

Ni, Yueqiong; Jensen, Kasper; Kouskoumvekaki, Eirini

2017-01-01

NutriChem is a database generated by text mining of 21 million MEDLINE abstracts that links plant-based foods with their small molecule components and human health effect. In this new, second release of NutriChem (NutriChem 2.0) we have integrated information on overlapping protein targets between...

Tropospheric ozone using an emission tagging technique in the CAM-Chem and WRF-Chem models

Science.gov (United States)

Lupascu, A.; Coates, J.; Zhu, S.; Butler, T. M.

2017-12-01

Tropospheric ozone is a short-lived climate forcing pollutant. High concentration of ozone can affect human health (cardiorespiratory and increased mortality due to long-term exposure), and also it damages crops. Attributing ozone concentrations to the contributions from different sources would indicate the effects of locally emitted or transported precursors on ozone levels in specific regions. This information could be used as an important component of the design of emissions reduction strategies by indicating which emission sources could be targeted for effective reductions, thus reducing the burden of ozone pollution. Using a "tagging" approach within the CAM-Chem (global) and WRF-Chem (regional) models, we can quantify the contribution of individual emission of NOx and VOC precursors on air quality. Hence, when precursor emissions of NOx are tagged, we have seen that the largest contributors on ozone levels are the anthropogenic sources, while in the case of precursor emissions of VOCs, the biogenic sources and methane account for more than 50% of ozone levels. Further, we have extended the NOx tagging method in order to investigate continental source region contributions to concentrations of ozone over various receptor regions over the globe, with a zoom over Europe. In general, summertime maximum ozone in most receptor regions is largely attributable to local emissions of anthropogenic NOx and biogenic VOC. During the rest of the year, especially during springtime, ozone in most receptor regions shows stronger influences from anthropogenic emissions of NOx and VOC in remote source regions.

3D-e-Chem-VM: Structural Cheminformatics Research Infrastructure in a Freely Available Virtual Machine.

Science.gov (United States)

McGuire, Ross; Verhoeven, Stefan; Vass, Márton; Vriend, Gerrit; de Esch, Iwan J P; Lusher, Scott J; Leurs, Rob; Ridder, Lars; Kooistra, Albert J; Ritschel, Tina; de Graaf, Chris

2017-02-27

3D-e-Chem-VM is an open source, freely available Virtual Machine ( http://3d-e-chem.github.io/3D-e-Chem-VM/ ) that integrates cheminformatics and bioinformatics tools for the analysis of protein-ligand interaction data. 3D-e-Chem-VM consists of software libraries, and database and workflow tools that can analyze and combine small molecule and protein structural information in a graphical programming environment. New chemical and biological data analytics tools and workflows have been developed for the efficient exploitation of structural and pharmacological protein-ligand interaction data from proteomewide databases (e.g., ChEMBLdb and PDB), as well as customized information systems focused on, e.g., G protein-coupled receptors (GPCRdb) and protein kinases (KLIFS). The integrated structural cheminformatics research infrastructure compiled in the 3D-e-Chem-VM enables the design of new approaches in virtual ligand screening (Chemdb4VS), ligand-based metabolism prediction (SyGMa), and structure-based protein binding site comparison and bioisosteric replacement for ligand design (KRIPOdb).

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.;

76 FR 10500 - Nationally Recognized Testing Laboratories Fees

Science.gov (United States)

2011-02-25

....'' Nat'l Cable Television Ass'n v. U.S., 415 U.S. 336 (1974), quoting H.R. Rep. No. 82-384, at 2-3 (1951... Court decided the companion cases of Nat'l Cable Television Ass'n, 415 U.S. 336, and Fed. Power Comm'n v... companies. Fed. Power Comm'n, 415 U.S. at 349. In Nat'l Cable Television Ass'n, Inc. v. FCC, 554 F.2d 1094...

Improved Near Real Time WRF-Chem Volcanic Emission Prediction and Impacts of Ash Aerosol on Weather.

Science.gov (United States)

Stuefer, M.; Webley, P. W.; Hirtl, M.

2017-12-01

We use the numerical Weather Research Forecasting (WRF) model with online Chemistry (WRF-Chem) to investigate the regional effects of volcanic aerosol on weather. A lot of observational data have become available since the Icelandic eruption of Eyjafjallajökull in spring 2010. The observed plume characteristics and meteorological data have been exploited for volcanic WRF-Chem case studies. We concluded that the Eyjafjallajökull ash plume resulted in significant direct aerosol effects altering the state of the atmosphere over large parts of Europe. The WRF-Chem model runs show near surface temperature differences up to 3ºC, altered vertical stability, changed pressure- and wind fields within the atmosphere loaded with ash aerosol. The modeled results have been evaluated with lidar network data, and ground and balloon based observations all over Europe. Besides case studies, we use WRF-Chem to build an improved volcanic ash decision support system that NOAA can use within the Volcanic Ash Advisory Center (VAAC) system. Realistic eruption source parameter (ESP) estimates are a main challenge in predicting volcanic emission dispersion in near real time. We implemented historic ESP into the WRF-Chem preprocessing routine, which can be used as a first estimate to assess a volcanic plume once eruption activity is reported. In a second step, a range of varying plume heights has been associated with the different ash variables within WRF-Chem, resulting in an assembly of different plume scenarios within one WRF-Chem model run. Once there is plume information available from ground or satellite observations, the forecaster has the option to select the corresponding ash variable that best matches the observations. In addition we added an automatic domain generation tool to create near real time WRF-Chem model runs anywhere on the globe by reducing computing expenses at the same time.

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).

First-order, stationary mean-field games with congestion

KAUST Repository

Evangelista, David

2018-04-30

Mean-field games (MFGs) are models for large populations of competing rational agents that seek to optimize a suitable functional. In the case of congestion, this functional takes into account the difficulty of moving in high-density areas. Here, we study stationary MFGs with congestion with quadratic or power-like Hamiltonians. First, using explicit examples, we illustrate two main difficulties: the lack of classical solutions and the existence of areas with vanishing densities. Our main contribution is a new variational formulation for MFGs with congestion. With this formulation, we prove the existence and uniqueness of solutions. Finally, we consider applications to numerical methods.

First-order, stationary mean-field games with congestion

KAUST Repository

Evangelista, David; Ferreira, Rita; Gomes, Diogo A.; Nurbekyan, Levon; Voskanyan, Vardan K.

2018-01-01

Mean-field games (MFGs) are models for large populations of competing rational agents that seek to optimize a suitable functional. In the case of congestion, this functional takes into account the difficulty of moving in high-density areas. Here, we study stationary MFGs with congestion with quadratic or power-like Hamiltonians. First, using explicit examples, we illustrate two main difficulties: the lack of classical solutions and the existence of areas with vanishing densities. Our main contribution is a new variational formulation for MFGs with congestion. With this formulation, we prove the existence and uniqueness of solutions. Finally, we consider applications to numerical methods.

Solubilization methods and reference 2-DE map of cow milk fat globules.

Science.gov (United States)

Bianchi, Laura; Puglia, Michele; Landi, Claudia; Matteoni, Silvia; Perini, Daniele; Armini, Alessandro; Verani, Margherita; Trombetta, Claudia; Soldani, Patrizia; Roncada, Paola; Greppi, Gianfranco; Pallini, Vitaliano; Bini, Luca

2009-07-21

Milk fat globules (MFGs) are secretory vesicles assembled and secreted by mammary epithelial cells during lactation. They consist of fat globules surrounded by a lipid bilayer membrane which is derived from the apical membrane of the lactating cells. MFGs contain, besides lipids, proteins from the apical plasma membrane and from the cytoplasmatic material. Their peculiar vesicle nature makes them a suitable and easily available source of biological material in monitoring the physiopathological state of the mammary gland. Unfortunately, the conspicuous lipidic component of MFGs consistently limits protein extraction and purification for MFG proteomic investigations. This work deals with the development of a suitable procedure for protein extraction from the cow MFGs in order to qualitatively and quantitatively improve 2-D electropherograms of the MFG. MFGs were purified from raw milk by centrifugation and then delipidated/precipitated. The resulting protein pellets were solubilised using four different 2-D SDS PAGE compatible lysis buffers. Applied methodological procedures for protein extraction and evaluation of the resulting 2-D protein-pattern are presented and discussed. Using these procedures a reference 2-D map of cow milk fat globules is also reported. The majority of the obtained identifications was represented by proteins involved in lipid synthesis or in fat globule secretion.

ChemCam on MSL 2009: first laser induced breakdown spectrometer for space science

Energy Technology Data Exchange (ETDEWEB)

Wiens, Roger C [Los Alamos National Laboratory

2008-01-01

ChemCam is one of the 10 instrument suites on the Mars Science Laboratory, a martian rover being built by Jet Propulsion Laboratory, for the next NASA mission to Mars (MSL 2009). ChemCam is an instrument package consisting of two remote sensing instruments: a Laser-Induced Breakdown Spectrometer (LIBS) and a Remote Micro-Imager (RMI). LIBS provides elemental compositions of rocks and soils, while the RMI places the LIBS analyses in their geomorphologic context. Both instruments rely on an autofocus capability to precisely focus on the chosen target, located at distances from the rover comprised between 1 and 9 m for LIBS, and 2 m and infinity for RMI. ChemCam will help determine which samples, within the vicinity of the MSL rover, are of sufficient interest to use the contact and in-situ instruments for further characterization. It will provide valuable analyses of samples that are inaccessible to contact and in-situ instruments, and of a much larger number of samples than can be done with this kind of instrument. ChemCam also has a capability to provide passive spectroscopy data of rocks and soils on Mars. ChemCam hardware consists of a Mast Unit (MU), provided by France, and a Body Unit (BU) built and tested in the USA. The Flight Model of the MU is assembled, tested and now available in the USA, while the BU is currently being assembled and tested. Both will be connected by the end of year '08 for end-to-end functional and performance tests, before delivery to JPL and assembly on the MSL rover. Launch is scheduled for October 09. After describing the concept of ChemCam, this presentation focuses on its French part, Mast Unit. The results presented show that Mast Unit is able to generate a plasma and collect its light, over the full applicable ranges of distances and temperatures on Mars.

One-Dimensional Forward–Forward Mean-Field Games

Energy Technology Data Exchange (ETDEWEB)

Gomes, Diogo A., E-mail: diogo.gomes@kaust.edu.sa; Nurbekyan, Levon; Sedjro, Marc [King Abdullah University of Science and Technology (KAUST), CEMSE Division (Saudi Arabia)

2016-12-15

While the general theory for the terminal-initial value problem for mean-field games (MFGs) has achieved a substantial progress, the corresponding forward–forward problem is still poorly understood—even in the one-dimensional setting. Here, we consider one-dimensional forward–forward MFGs, study the existence of solutions and their long-time convergence. First, we discuss the relation between these models and systems of conservation laws. In particular, we identify new conserved quantities and study some qualitative properties of these systems. Next, we introduce a class of wave-like equations that are equivalent to forward–forward MFGs, and we derive a novel formulation as a system of conservation laws. For first-order logarithmic forward–forward MFG, we establish the existence of a global solution. Then, we consider a class of explicit solutions and show the existence of shocks. Finally, we examine parabolic forward–forward MFGs and establish the long-time convergence of the solutions.

One-Dimensional Forward–Forward Mean-Field Games

KAUST Repository

Gomes, Diogo A.; Nurbekyan, Levon; Sedjro, Marc

2016-01-01

While the general theory for the terminal-initial value problem for mean-field games (MFGs) has achieved a substantial progress, the corresponding forward–forward problem is still poorly understood—even in the one-dimensional setting. Here, we consider one-dimensional forward–forward MFGs, study the existence of solutions and their long-time convergence. First, we discuss the relation between these models and systems of conservation laws. In particular, we identify new conserved quantities and study some qualitative properties of these systems. Next, we introduce a class of wave-like equations that are equivalent to forward–forward MFGs, and we derive a novel formulation as a system of conservation laws. For first-order logarithmic forward–forward MFG, we establish the existence of a global solution. Then, we consider a class of explicit solutions and show the existence of shocks. Finally, we examine parabolic forward–forward MFGs and establish the long-time convergence of the solutions.

One-Dimensional Forward–Forward Mean-Field Games

KAUST Repository

Gomes, Diogo A.

2016-11-01

While the general theory for the terminal-initial value problem for mean-field games (MFGs) has achieved a substantial progress, the corresponding forward–forward problem is still poorly understood—even in the one-dimensional setting. Here, we consider one-dimensional forward–forward MFGs, study the existence of solutions and their long-time convergence. First, we discuss the relation between these models and systems of conservation laws. In particular, we identify new conserved quantities and study some qualitative properties of these systems. Next, we introduce a class of wave-like equations that are equivalent to forward–forward MFGs, and we derive a novel formulation as a system of conservation laws. For first-order logarithmic forward–forward MFG, we establish the existence of a global solution. Then, we consider a class of explicit solutions and show the existence of shocks. Finally, we examine parabolic forward–forward MFGs and establish the long-time convergence of the solutions.

Are multi family groups appropriate for patients with first episode psychosis?

DEFF Research Database (Denmark)

Rossberg, Jan Ivar; Johannessen, J O; Klungsoyr, O

2010-01-01

OBJECTIVE: To compare outcome over 5 years for patients who participated in multi family groups (MFGs) to those who refused or were not offered participation. METHOD: Of 301 first episode psychotic patients aged 15-65 years, 147 participated in MFGs. Outcome was measured by drop-out rates, positive...

Soil Diversity and Hydration as Observed by ChemCam at Gale Crater, Mars

Science.gov (United States)

Meslin, P.-Y.; Gasnault, O.; Forni, O.; Schröder, 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.; Mangold, N.; Ehlmann, B.; Lanza, N.; Harri, A.-M.; Anderson, R.; Rampe, E.; McConnochie, T. H.; Pinet, P.; Blaney, D.; Léveillé, R.; 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.; Gondet, B.; Grotzinger, J.; Herkenhoff, K.; Johnson, J.; Lacour, J.-L.; Langevin, Y.; Leshin, L.; Lewin, E.; Madsen, M. B.; Melikechi, N.; Mezzacappa, A.; Mischna, M. A.; Moores, J. E.; Newsom, H.; Ollila, A.; Perez, R.; Renno, N.; Sirven, J.-B.; Tokar, R.; de la Torre, M.; d'Uston, L.; Vaniman, D.; Yingst, A.; Kemppinen, Osku; Minitti, Michelle; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Weigle, Gerald; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Mauchien, Patrick; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Schieber, Juergen; Geffroy, Claude; Baratoux, David; Cros, Alain; Lee, Qiu-Mei; Pallier, Etienne; Parot, Yann; Toplis, Mike; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Robert, François; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Little, Cynthia; Nelson, Tony; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Fassett, Caleb; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Eigenbrode, Jennifer; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Posner, Arik; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Brinza, David; Calef, Fred; Christensen, Lance; Crisp, Joy A.; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Vasavada, Ashwin R.; Webster, Christopher R.; Yen, Albert; Cucinotta, Francis; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Nolan, Thomas; Radziemski, Leon; Berman, Daniel; Dobrea, Eldar Noe; Williams, Rebecca M. E.; Lewis, Kevin; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey

2013-09-01

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.

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.; ,; 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.; ,; 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.

Sulfur Geochemical Analysis and Interpretation with ChemCam on the Curiosity Rover

Science.gov (United States)

Clegg, S. M.; Anderson, R. B.; Frydenvang, J.; Forni, O.; Newsom, H. E.; Blaney, D. L.; Maurice, S.; Wiens, R. C.

2017-12-01

The Curiosity rover has encountered many forms of sulfur including calcium sulfate veins [1], hydrated Mg sulfates, and Fe sulfates along the traverse through Gale crater. A new SO3 calibration model for the remote Laser-Induced Breakdown Spectroscopy (LIBS) technique used by the ChemCam instrument enables improved quantitative analysis of SO3, which has not been previously reported by ChemCam on a routine or quantitative basis. In this paper, the details of this new LIBS calibration model will be described and applied to many disparate Mars targets. Among them, Mavor contains a calcium sulfate vein surrounded by bedrock. In contrast, Jake M. is a float rock, Wernecke is a bedrock, Cumberland and Windjana are drill targets. In 2015 the ChemCam instrument team completed a re-calibration of major elements based on a significantly expanded set of >500 geochemical standards using the ChemCam testbed at Los Alamos National Laboratory [2]. In addition to these standards, the SO3 compositional range was recently extended with a series of doped samples containing various mixtures of Ca- and Mg-sulfate with basalt BHVO2. Spectra from these standards were processed per [4]. Calibration and Mars spectra were converted to peak-area-summed LIBS spectra that enables the SO3 calibration. These peak-area spectra were used to generate three overlapping partial least squares (PLS1) calibration sub-models as described by Anderson et al. [3, 5]. ChemCam analysis of Mavor involved a 3x3 raster in which locations 5 and 6 primarily probed Ca-sulfate material. The new ChemCam SO3 compositions for Mavor 5 and Mavor 6 are 48.6±1.2 and 50.3±1.2 wt% SO3, respectively. The LIBS spectra also recorded the presence of other elements that are likely responsible for the departure from pure Ca-sulfate chemistry. On the low-abundance side, the remaining 7 Mavor locations, Jake M., Cumberland, Windjana, and Wernecke all contain much lower SO3, between 1.4±0.5 wt% and 2.3±0.3 wt% SO3. [1] Nachon et

ChemANDTM - a system health monitor for plant chemistry

International Nuclear Information System (INIS)

Turner, C.W.; Mitchel, G.R.; Balakrishnan, P.V.; Tosello, G.

1999-07-01

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 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

OrChem - An open source chemistry search engine for Oracle®

Science.gov (United States)

2009-01-01

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. PMID:20298521

OrChem - An open source chemistry search engine for Oracle(R).

Science.gov (United States)

Rijnbeek, Mark; Steinbeck, Christoph

2009-10-22

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. 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. 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.

On the Existence of Solutions for Stationary Mean-Field Games with Congestion

KAUST Repository

Evangelista, David; Gomes, Diogo A.

2017-01-01

Mean-field games (MFGs) are models of large populations of rational agents who seek to optimize an objective function that takes into account their location and the distribution of the remaining agents. Here, we consider stationary MFGs with congestion and prove the existence of stationary solutions. Because moving in congested areas is difficult, agents prefer to move in non-congested areas. As a consequence, the model becomes singular near the zero density. The existence of stationary solutions was previously obtained for MFGs with quadratic Hamiltonians thanks to a very particular identity. Here, we develop robust estimates that give the existence of a solution for general subquadratic Hamiltonians.

On the Existence of Solutions for Stationary Mean-Field Games with Congestion

KAUST Repository

Evangelista, David

2017-09-11

Mean-field games (MFGs) are models of large populations of rational agents who seek to optimize an objective function that takes into account their location and the distribution of the remaining agents. Here, we consider stationary MFGs with congestion and prove the existence of stationary solutions. Because moving in congested areas is difficult, agents prefer to move in non-congested areas. As a consequence, the model becomes singular near the zero density. The existence of stationary solutions was previously obtained for MFGs with quadratic Hamiltonians thanks to a very particular identity. Here, we develop robust estimates that give the existence of a solution for general subquadratic Hamiltonians.

CASSINI S MIMI CHEMS SENSOR CALIBRATED DATA V1.0

Data.gov (United States)

National Aeronautics and Space Administration — The Cassini Magnetospheric Imaging Instrument(MIMI) Charge Energy Mass Spectrometer (CHEMS) contains a deflection system and an overall field of view of 159 x 4 deg....

75 FR 65261 - Virginia Graeme Baker Pool and Spa Safety Act; Public Accommodation

Science.gov (United States)

2010-10-22

... Condominium Ass'n, 2005 U.S. Dist. LEXIS 41601 (November 22, 2005) (condominium buildings may be covered as... characteristics normally associated with a hotel, motel, or inn); Thompson v. Sand Cliffs Owners Ass'n, Inc., 1998...

Data mining a small molecule drug screening representative subset from NIH PubChem.

Science.gov (United States)

Xie, Xiang-Qun; Chen, Jian-Zhong

2008-03-01

PubChem is a scientific showcase of the NIH Roadmap Initiatives. It is a compound repository created to facilitate information exchange and data sharing among the NIH Roadmap-funded Molecular Library Screening Center Network (MLSCN) and the scientific community. However, PubChem has more than 10 million records of compound information. It will be challenging to conduct a drug screening of the whole database of millions of compounds. Thus, the purpose of the present study was to develop a data mining cheminformatics approach in order to construct a representative and structure-diverse sublibrary from the large PubChem database. In this study, a new chemical diverse representative subset, rePubChem, was selected by whole-molecule chemistry-space matrix calculation using the cell-based partition algorithm. The representative subset was generated and was then subjected to evaluations by compound property analyses based on 1D and 2D molecular descriptors. The new subset was also examined and assessed for self-similarity analysis based on 2D molecular fingerprints in comparing with the source compound library. The new subset has a much smaller library size (540K compounds) with minimum similarity and redundancy without loss of the structural diversity and basic molecular properties of its parent library (5.3 million compounds). The new representative subset library generated could be a valuable structure-diverse compound resource for in silico virtual screening and in vitro HTS drug screening. In addition, the established subset generation method of using the combined cell-based chemistry-space partition metrics with pairwised 2D fingerprint-based similarity search approaches will also be important to a broad scientific community interested in acquiring structurally diverse compounds for efficient drug screening, building representative virtual combinatorial chemistry libraries for syntheses, and data mining large compound databases like the PubChem library in general.

Development and Performance of the Modularized, High-performance Computing and Hybrid-architecture Capable GEOS-Chem Chemical Transport Model

Science.gov (United States)

Long, M. S.; Yantosca, R.; Nielsen, J.; Linford, J. C.; Keller, C. A.; Payer Sulprizio, M.; Jacob, D. J.

2014-12-01

The GEOS-Chem global chemical transport model (CTM), used by a large atmospheric chemistry research community, has been reengineered to serve as a platform for a range of computational atmospheric chemistry science foci and applications. Development included modularization for coupling to general circulation and Earth system models (ESMs) and the adoption of co-processor capable atmospheric chemistry solvers. This was done using an Earth System Modeling Framework (ESMF) interface that operates independently of GEOS-Chem scientific code to permit seamless transition from the GEOS-Chem stand-alone serial CTM to deployment as a coupled ESM module. In this manner, the continual stream of updates contributed by the CTM user community is automatically available for broader applications, which remain state-of-science and directly referenceable to the latest version of the standard GEOS-Chem CTM. These developments are now available as part of the standard version of the GEOS-Chem CTM. The system has been implemented as an atmospheric chemistry module within the NASA GEOS-5 ESM. The coupled GEOS-5/GEOS-Chem system was tested for weak and strong scalability and performance with a tropospheric oxidant-aerosol simulation. Results confirm that the GEOS-Chem chemical operator scales efficiently for any number of processes. Although inclusion of atmospheric chemistry in ESMs is computationally expensive, the excellent scalability of the chemical operator means that the relative cost goes down with increasing number of processes, making fine-scale resolution simulations possible.

77 FR 31486 - Virginia Regulatory Program

Science.gov (United States)

2012-05-29

... United States Court of Appeals for the District of Columbia Circuit in Nat'l Mining Ass'n v. Kempthorne... Federal VER regulations promulgated by OSM on December 17, 1999 (64 FR 70766-70838). Nat'l Mining Ass'n v...

NutriChem: a systems chemical biology resource to explore the medicinal value of plant-based foods

DEFF Research Database (Denmark)

Jensen, Kasper; Panagiotou, Gianni; Kouskoumvekaki, Irene

2015-01-01

million MEDLINE abstracts for information thatlinks plant-based foods with their small moleculecomponents and human disease phenotypes. Nu-triChem contains text-mined data for 18478 pairs of1772 plant-based foods and 7898 phytochemicals,and 6242 pairs of 1066 plant-based foods and 751diseases. In addition......,there is currently no exhaustive resource on thehealth benefits associated to specific dietary inter-ventions, or a resource covering the broad molecu-lar content of food. Here we present the first releaseof NutriChem, available athttp://cbs.dtu.dk/services/NutriChem-1.0, a database generated by text miningof 21...

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.

New developments on ChemCam laser transmitter and potential applications for other planetology programs

Science.gov (United States)

Faure, Benoît; Durand, Eric; Maurice, Sylvestre; Bruneau, Didier; Montmessin, Franck

2017-11-01

ChemCam is a LIBS Instrument mounted on the MSL 2011 NASA mission. The laser transmitter of this Instrument has been developed by the French society Thales Optronique (former Thales Laser) with a strong technical support from CNES. The paper will first rapidly present the performance of this laser and will then describe the postChemCam developments realized on and around this laser for new planetology programs.

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.

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.

ChemNet: A Transferable and Generalizable Deep Neural Network for Small-Molecule Property Prediction

Energy Technology Data Exchange (ETDEWEB)

Goh, Garrett B.; Siegel, Charles M.; Vishnu, Abhinav; Hodas, Nathan O.

2017-12-08

With access to large datasets, deep neural networks through representation learning have been able to identify patterns from raw data, achieving human-level accuracy in image and speech recognition tasks. However, in chemistry, availability of large standardized and labelled datasets is scarce, and with a multitude of chemical properties of interest, chemical data is inherently small and fragmented. In this work, we explore transfer learning techniques in conjunction with the existing Chemception CNN model, to create a transferable and generalizable deep neural network for small-molecule property prediction. Our latest model, ChemNet learns in a semi-supervised manner from inexpensive labels computed from the ChEMBL database. When fine-tuned to the Tox21, HIV and FreeSolv dataset, which are 3 separate chemical tasks that ChemNet was not originally trained on, we demonstrate that ChemNet exceeds the performance of existing Chemception models, contemporary MLP models that trains on molecular fingerprints, and it matches the performance of the ConvGraph algorithm, the current state-of-the-art. Furthermore, as ChemNet has been pre-trained on a large diverse chemical database, it can be used as a universal “plug-and-play” deep neural network, which accelerates the deployment of deep neural networks for the prediction of novel small-molecule chemical properties.

75 FR 80746 - Interpretation of Rest Requirements

Science.gov (United States)

2010-12-23

... Whitlow Letter in its interpretations of section 121.471(g). See Air Transport Ass'n of America, Inc. v. F... 121.471(g) and 135.263(d) is interpreted in two different ways. See Air Transport Ass'n, 291 F.3d at...

Automation and semantics: the CombeChem experience

OpenAIRE

Frey, Jeremy G.

2004-01-01

Some of the experiences of the CombeChem e-Science project in relation to both automation and the need for semantics in combining modern computer science techniques and chemistry are discussed. In particular the aspects of the smart laboratory, large scale data handling and the way this impacts on the necessary database technology are discussed. In addition some of the ways in which the grid can enable greater user interaction with services such as the National Crystallography Service and imp...

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.

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.

29 CFR 780.133 - Farmers' cooperative as a “farmer.”

Science.gov (United States)

2010-07-01

...(f) (Farmers Reservoir Co. v. McComb, 337 U.S. 755; Goldberg v. Crowley Ridge Ass'n., 295 F. 2d 7; McComb v. Puerto Rico Tobacco Marketing Co-op Ass'n., 80 F. Supp. 953, 181 F. 2d 697). The legislative...

78 FR 67928 - Land Acquisitions: Appeals of Land Acquisition Decisions

Science.gov (United States)

2013-11-13

... & Livestock Ass'n v. Anderson, 361 F.Supp.2d 1045, 1051-52 (D.N.D. 2005). When the AS-IA issues a decision to... relief under that section. See, e.g., Corning Savings & Loan Ass'n v. Federal Home Loan Bank Board, 562 F...

WRF-Chem Model Simulations of Arizona Dust Storms

Science.gov (United States)

Mohebbi, A.; Chang, H. I.; Hondula, D.

2017-12-01

The online Weather Research and Forecasting model with coupled chemistry module (WRF-Chem) is applied to simulate the transport, deposition and emission of the dust aerosols in an intense dust outbreak event that took place on July 5th, 2011 over Arizona. Goddard Chemistry Aerosol Radiation and Transport (GOCART), Air Force Weather Agency (AFWA), and University of Cologne (UoC) parameterization schemes for dust emission were evaluated. The model was found to simulate well the synoptic meteorological conditions also widely documented in previous studies. The chemistry module performance in reproducing the atmospheric desert dust load was evaluated using the horizontal field of the Aerosol Optical Depth (AOD) from Moderate Resolution Imaging Spectro (MODIS) radiometer Terra/Aqua and Aerosol Robotic Network (AERONET) satellites employing standard Dark Target (DT) and Deep Blue (DB) algorithms. To assess the temporal variability of the dust storm, Particulate Matter mass concentration data (PM10 and PM2.5) from Arizona Department of Environmental Quality (AZDEQ) ground-based air quality stations were used. The promising performance of WRF-Chem indicate that the model is capable of simulating the right timing and loading of a dust event in the planetary-boundary-layer (PBL) which can be used to forecast approaching severe dust events and to communicate an effective early warning.

Cleanup of metals and hydrocarbons contaminated soils using the ChemTech process

International Nuclear Information System (INIS)

Stephenson, R.; Yan, V.; Lim, S.

1997-01-01

The ChemTech soil treatment process, an on-site ex-situ system, comprised of a three-phase fluidized bed to scour, emulsify and chemically leach soil contaminants into a process water, was described. The cleaned soils are then removed from the process circuit by means of a hydrodynamic classifier. At this point they are suitable for return to the excavation site. The process was demonstrated on a pilot scale in January 1997 by Klohn-Crippen Consultants at a demonstration program of emerging and innovative technologies sponsored by the Bay Area Defence Conversion Action Team (BADCAT), to assist with the remediation of twelve closing military bases in the San Francisco area. The ChemTest demonstration involved the removal of copper, chromium, lead and zinc from the Hunter Point Naval Reserve, plus treatability tests on a number of other contaminated soil samples. The ChemTech process was selected by federal and state regulatory agencies from 21 proposed technologies on the basis of performance, effectiveness, low cost, and absence of secondary environmental impacts. This paper provides details of the demonstration program, addresses the applicability of the technology to other sites, and provides cost estimates of unit cleanup costs. 3 refs., 4 tabs., 4 figs

75 FR 24828 - Promoting a Competitive Market for Capacity Reassignments

Science.gov (United States)

2010-05-06

... part and remanded in part sub nom. Interstate Natural Gas Ass'n of America v. FERC, 285 F.3d 18, 350 U... ] 61,088 (2004), aff'd sub nom. American Gas Ass'n v. FERC, 428 F.3d 255, 368 U.S. App. DC 176 (DC Cir...

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

KAUST Repository

Ebner, David C.; Bagdanoff, Jeffrey T.; Ferreira, Eric M.; McFadden, Ryan; Caspi, Daniel D.; Trend, Raissa M.; Stoltz, Brian M.

2010-01-01

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.

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.

ChemSession'09 - 6. Warsaw Seminar of the PhD Students in Chemistry - Abstracts; ChemSession'09 - 6. Warszawskie Seminarium Doktorantow Chemikow - Streszczenia

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Book of Abstracts contains short descriptions of presentations 3 lectures and 105 posters presented during ChemSession'09 - 6{sup th} 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.

ChemSession'08 - 5. Warsaw Seminar of the PhD Students in Chemistry - Abstracts; ChemSession'08 - 5. Warszawskie Seminarium Doktorantow Chemikow - Streszczenia

Energy Technology Data Exchange (ETDEWEB)

Madura, I [ed.

2008-07-01

Book of Abstracts consists of short descriptions of presentations: 5 lectures and 127 posters presented during ChemSession'08 - 5{sup th} 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.

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.

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

Science.gov (United States)

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

2012-08-07

: 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.

Interactive Gaussian Graphical Models for Discovering Depth Trends in ChemCam Data

Science.gov (United States)

Oyen, D. A.; Komurlu, C.; Lanza, N. L.

2018-04-01

Interactive Gaussian graphical models discover surface compositional features on rocks in ChemCam targets. Our approach visualizes shot-to-shot relationships among LIBS observations, and identifies the wavelengths involved in the trend.

ChemAND{sup TM} - a system health monitor for plant chemistry

Energy Technology Data Exchange (ETDEWEB)

Turner, C.W.; Mitchel, G.R.; Balakrishnan, P.V.; Tosello, G

1999-07-01

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 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

ChemProt: A disease chemical biology database

DEFF Research Database (Denmark)

Taboureau, Olivier; Oprea, Tudor I.

2013-01-01

The integration of chemistry, biology, and informatics to study drug actions across multiple biological targets, pathways, and biological systems is an emerging paradigm in drug discovery. Rather than reducing a complex system to simplistic models, fields such as chemogenomics and translational...... informatics are seeking to build a holistic model for a better understanding of the drug pharmacology and clinical effects. Here we will present a webserver called ChemProt that can assist, in silico, the drug actions in the context of cellular and disease networks and contribute in the field of disease...... chemical biology, drug repurposing, and off-target effects prediction....

Quality of life, treatment adherence, and locus of control: multiple family groups for chronic medical illnesses.

Science.gov (United States)

López-Larrosa, Silvia

2013-12-01

The Multiple Family Groups (MFGs) approach for patients with a chronic medical illness and their families is a structured psychoeducational program that unfolds in six weekly 90-minute sessions. In the MFGs, patients and family members explore new ways to balance illness and nonillness priorities in family life (Steinglass, 1998; Steinglass, 2000 Cuadernos de Terapia Familiar, 44-45, 11; Steinglass, Ostroff, & Steinglass, 2011 Family Process, 50, 393). © FPI, Inc.

Incorporation of a Chemical Equilibrium Equation of State into LOCI-Chem

Science.gov (United States)

Cox, Carey F.

2005-01-01

Renewed interest in development of advanced high-speed transport, reentry vehicles and propulsion systems has led to a resurgence of research into high speed aerodynamics. As this flow regime is typically dominated by hot reacting gaseous flow, efficient models for the characteristic chemical activity are necessary for accurate and cost effective analysis and design of aerodynamic vehicles that transit this regime. The LOCI-Chem code recently developed by Ed Luke at Mississippi State University for NASA/MSFC and used by NASA/MSFC and SSC represents an important step in providing an accurate, efficient computational tool for the simulation of reacting flows through the use of finite-rate kinetics [3]. Finite rate chemistry however, requires the solution of an additional N-1 species mass conservation equations with source terms involving reaction kinetics that are not fully understood. In the equilibrium limit, where the reaction rates approach infinity, these equations become very stiff. Through the use of the assumption of local chemical equilibrium the set of governing equations is reduced back to the usual gas dynamic equations, and thus requires less computation, while still allowing for the inclusion of reacting flow phenomenology. The incorporation of a chemical equilibrium equation of state module into the LOCI-Chem code was the primary objective of the current research. The major goals of the project were: (1) the development of a chemical equilibrium composition solver, and (2) the incorporation of chemical equilibrium solver into LOCI-Chem. Due to time and resource constraints, code optimization was not considered unless it was important to the proper functioning of the code.

Regional modelling of polycyclic aromatic hydrocarbons: WRF-Chem-PAH model development and East Asia case studies

Science.gov (United States)

Mu, Qing; Lammel, Gerhard; Gencarelli, Christian N.; Hedgecock, Ian M.; Chen, Ying; Přibylová, Petra; Teich, Monique; Zhang, Yuxuan; Zheng, Guangjie; van Pinxteren, Dominik; Zhang, Qiang; Herrmann, Hartmut; Shiraiwa, Manabu; Spichtinger, Peter; Su, Hang; Pöschl, Ulrich; Cheng, Yafang

2017-10-01

Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants, with increasing emissions in pace with economic development in East Asia, but their distribution and fate in the atmosphere are not yet well understood. We extended the regional atmospheric chemistry model WRF-Chem (Weather Research Forecast model with Chemistry module) to comprehensively study the atmospheric distribution and the fate of low-concentration, slowly degrading semivolatile compounds. The WRF-Chem-PAH model reflects the state-of-the-art understanding of current PAHs studies with several new or updated features. It was applied for PAHs covering a wide range of volatility and hydrophobicity, i.e. phenanthrene, chrysene and benzo[a]pyrene, in East Asia. Temporally highly resolved PAH concentrations and particulate mass fractions were evaluated against observations. The WRF-Chem-PAH model is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions. Sensitivity study shows that the heterogeneous reaction with ozone and the homogeneous reaction with the nitrate radical significantly influence the fate and distributions of PAHs. The methods to implement new species and to correct the transport problems can be applied to other newly implemented species in WRF-Chem.

Diagenetic Features Analyzed by ChemCam/Curiosity at Pahrump Hills, Gale Crater, Mars

Science.gov (United States)

Nachon, M.; Mangold, N.; Cousin, A.; Forni, O.; Anderson, R. B.; Blank, J. G.; Calef, F.; Clegg, S.; Fabre, C.; Fisk, M.;

A New WRF-Chem Treatment for Studying Regional Scale Impacts of Cloud-Aerosol Interactions in Parameterized Cumuli

Energy Technology Data Exchange (ETDEWEB)

Berg, Larry K.; Shrivastava, ManishKumar B.; Easter, Richard C.; Fast, Jerome D.; Chapman, Elaine G.; Liu, Ying

2015-01-01

A new treatment of cloud-aerosol interactions within parameterized shallow and deep convection has been implemented in WRF-Chem that can be used to better understand the aerosol lifecycle over regional to synoptic scales. The modifications to the model to represent cloud-aerosol interactions include treatment of the cloud dropletnumber mixing ratio; key cloud microphysical and macrophysical parameters (including the updraft fractional area, updraft and downdraft mass fluxes, and entrainment) averaged over the population of shallow clouds, or a single deep convective cloud; and vertical transport, activation/resuspension, aqueous chemistry, and wet removal of aerosol and trace gases in warm clouds. Thesechanges have been implemented in both the WRF-Chem chemistry packages as well as the Kain-Fritsch cumulus parameterization that has been modified to better represent shallow convective clouds. Preliminary testing of the modified WRF-Chem has been completed using observations from the Cumulus Humilis Aerosol Processing Study (CHAPS) as well as a high-resolution simulation that does not include parameterized convection. The simulation results are used to investigate the impact of cloud-aerosol interactions on the regional scale transport of black carbon (BC), organic aerosol (OA), and sulfate aerosol. Based on the simulations presented here, changes in the column integrated BC can be as large as -50% when cloud-aerosol interactions are considered (due largely to wet removal), or as large as +35% for sulfate in non-precipitating conditions due to the sulfate production in the parameterized clouds. The modifications to WRF-Chem version 3.2.1 are found to account for changes in the cloud drop number concentration (CDNC) and changes in the chemical composition of cloud-drop residuals in a way that is consistent with observations collected during CHAPS. Efforts are currently underway to port the changes described here to WRF-Chem version 3.5, and it is anticipated that they

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

Science.gov (United States)

Sessions, W. R.; Fuelberg, H. E.; Kahn, R. A.; Winker, D. M.

2011-06-01

The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia. One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and local atmospheric stability. This paper describes a case study of a 10 day period during the Spring phase of ARCTAS. It compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3-5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA) and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE). Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors. When FLAMBE provides input to the 1-D plume rise model, the resulting injection heights exhibit the best agreement with satellite-observed injection heights. The FLAMBE-derived heights are more realistic than those utilizing prep_chem_sources. Conversely, when the planetary boundary layer or the 3-5 km a.g.l. layer were filled with emissions, the resulting injection heights exhibit less agreement with observed plume heights

The ChemChar process

International Nuclear Information System (INIS)

Manahan, S.E.; Kinner, L.L.; Larsen, D.W.

1992-01-01

This paper reports on reverse-burn gasification is a thermochemical process that offers a number of advantages over conventional incineration for the treatment of a variety of waste materials. Patented as the ChemChar Process, reverse-burn gasification can treat wastes in the forms of solids, liquids, sludges, and soils. Waste constituents are destroyed by conversion to a combustible gas and to a dry, inert, carbonaceous solid which is either non-hazardous or can be readily mixed with cement to prevent leaching of the radioactive, toxic, or heavy metal constituents that are retained in the char residue or ash. In this way, reverse-burn gasification can be a very effective method for treating organic waste sludges containing heavy metals and mixed wastes consisting of hazardous chemicals contaminated with radioactive substances. As with any gasification waste treatment process, reverse-burn gasification offers inherent advantages in the areas of destruction efficiency and emissions control. This is because, instead of an exhaust gas that must treated to control emissions, gasification produces a combustible gas that is burned. Trace levels of contaminants are destroyed in burning the gas, and a catalyst may be employed, if necessary

Development of a Grid-Independent Geos-Chem Chemical Transport Model (v9-02) as an Atmospheric Chemistry Module for Earth System Models

Science.gov (United States)

Long, M. S.; Yantosca, R.; Nielsen, J. E; Keller, C. A.; Da Silva, A.; Sulprizio, M. P.; Pawson, S.; Jacob, D. J.

2015-01-01

The GEOS-Chem global chemical transport model (CTM), used by a large atmospheric chemistry research community, has been re-engineered to also serve as an atmospheric chemistry module for Earth system models (ESMs). This was done using an Earth System Modeling Framework (ESMF) interface that operates independently of the GEOSChem scientific code, permitting the exact same GEOSChem code to be used as an ESM module or as a standalone CTM. In this manner, the continual stream of updates contributed by the CTM user community is automatically passed on to the ESM module, which remains state of science and referenced to the latest version of the standard GEOS-Chem CTM. A major step in this re-engineering was to make GEOS-Chem grid independent, i.e., capable of using any geophysical grid specified at run time. GEOS-Chem data sockets were also created for communication between modules and with external ESM code. The grid-independent, ESMF-compatible GEOS-Chem is now the standard version of the GEOS-Chem CTM. It has been implemented as an atmospheric chemistry module into the NASA GEOS- 5 ESM. The coupled GEOS-5-GEOS-Chem system was tested for scalability and performance with a tropospheric oxidant-aerosol simulation (120 coupled species, 66 transported tracers) using 48-240 cores and message-passing interface (MPI) distributed-memory parallelization. Numerical experiments demonstrate that the GEOS-Chem chemistry module scales efficiently for the number of cores tested, with no degradation as the number of cores increases. Although inclusion of atmospheric chemistry in ESMs is computationally expensive, the excellent scalability of the chemistry module means that the relative cost goes down with increasing number of cores in a massively parallel environment.

Alkali trace elements in Gale crater, Mars, with ChemCam: Calibration update and geological implications

Science.gov (United States)

Payré, V.; Fabre, C.; Cousin, A.; Sautter, V.; Wiens, R. C.; Forni, O.; Gasnault, O.; Mangold, N.; Meslin, P.-Y.; Lasue, J.; Ollila, A.; Rapin, W.; Maurice, S.; Nachon, M.; Le Deit, L.; Lanza, N.; Clegg, S.

2017-03-01

The Chemistry Camera (ChemCam) instrument onboard Curiosity can detect minor and trace elements such as lithium, strontium, rubidium, and barium. Their abundances can provide some insights about Mars' magmatic history and sedimentary processes. We focus on developing new quantitative models for these elements by using a new laboratory database (more than 400 samples) that displays diverse compositions that are more relevant for Gale crater than the previous ChemCam database. These models are based on univariate calibration curves. For each element, the best model is selected depending on the results obtained by using the ChemCam calibration targets onboard Curiosity. New quantifications of Li, Sr, Rb, and Ba in Gale samples have been obtained for the first 1000 Martian days. Comparing these data in alkaline and magnesian rocks with the felsic and mafic clasts from the Martian meteorite NWA7533—from approximately the same geologic period—we observe a similar behavior: Sr, Rb, and Ba are more concentrated in soluble- and incompatible-element-rich mineral phases (Si, Al, and alkali-rich). Correlations between these trace elements and potassium in materials analyzed by ChemCam reveal a strong affinity with K-bearing phases such as feldspars, K-phyllosilicates, and potentially micas in igneous and sedimentary rocks. However, lithium is found in comparable abundances in alkali-rich and magnesium-rich Gale rocks. This very soluble element can be associated with both alkali and Mg-Fe phases such as pyroxene and feldspar. These observations of Li, Sr, Rb, and Ba mineralogical associations highlight their substitution with potassium and their incompatibility in magmatic melts.

One-Dimensional Stationary Mean-Field Games with Local Coupling

KAUST Repository

Gomes, Diogo A.; Nurbekyan, Levon; Prazeres, Mariana

2017-01-01

A standard assumption in mean-field game (MFG) theory is that the coupling between the Hamilton–Jacobi equation and the transport equation is monotonically non-decreasing in the density of the population. In many cases, this assumption implies the existence and uniqueness of solutions. Here, we drop that assumption and construct explicit solutions for one-dimensional MFGs. These solutions exhibit phenomena not present in monotonically increasing MFGs: low-regularity, non-uniqueness, and the formation of regions with no agents.

One-Dimensional Stationary Mean-Field Games with Local Coupling

KAUST Repository

Gomes, Diogo A.

2017-05-25

A standard assumption in mean-field game (MFG) theory is that the coupling between the Hamilton–Jacobi equation and the transport equation is monotonically non-decreasing in the density of the population. In many cases, this assumption implies the existence and uniqueness of solutions. Here, we drop that assumption and construct explicit solutions for one-dimensional MFGs. These solutions exhibit phenomena not present in monotonically increasing MFGs: low-regularity, non-uniqueness, and the formation of regions with no agents.

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.

Milk Fat Globules Hamper Adhesion of Enterohemorrhagic Escherichia coli to Enterocytes: In Vitro and in Vivo Evidence

Directory of Open Access Journals (Sweden)

Thomas Douëllou

2018-05-01

Full Text Available Enterohemorrhagic Escherichia coli (EHEC; E. coli are food-borne agents associated with gastroenteritis, enterocolitis, bloody diarrhea and the hemolytic-uremic syndrome (HUS. Bovine milk glycans have been shown to contain oligosaccharides which are similar to host epithelial cell receptors and can therefore prevent bacterial adhesion. This study aimed to describe interactions between EHEC O157:H7 EDL933 and O26:H11 21765 and milk fat globules (MFGs in raw milk and raw milk cheese, and the impact of MFGs on EHEC strains adhesion to the intestinal tract in vitro and in vivo. Both EHEC serotypes clearly associated with native bovine MFGs and significantly limited their adhesion to a co-culture of intestinal cells. The presence of MFGs in raw milk cheese had two effects on the adhesion of both EHEC serotypes to the intestinal tracts of streptomycin-treated mice. First, it delayed and reduced EHEC excretion in mouse feces for both strains. Second, the prime implantation site for both EHEC strains was 6 cm more proximal in the intestinal tracts of mice fed with contaminated cheese containing less than 5% of fat than in those fed with contaminated cheese containing 40% of fat. Feeding mice with 40% fat cheese reduced the intestinal surface contaminated with EHEC and may therefore decrease severity of illness.

Retrieval of water vapor column abundance and aerosol properties from ChemCam passive sky spectroscopy

Science.gov (United States)

McConnochie, Timothy H.; Smith, Michael D.; Wolff, Michael J.; Bender, Steve; Lemmon, Mark; Wiens, Roger C.; Maurice, Sylvestre; Gasnault, Olivier; Lasue, Jeremie; Meslin, Pierre-Yves; Harri, Ari-Matti; Genzer, Maria; Kemppinen, Osku; Martínez, Germán M.; DeFlores, Lauren; Blaney, Diana; Johnson, Jeffrey R.; Bell, James F.

2018-06-01

We derive water vapor column abundances and aerosol properties from Mars Science Laboratory (MSL) ChemCam passive mode observations of scattered sky light. This paper covers the methodology and initial results for water vapor and also provides preliminary results for aerosols. The data set presented here includes the results of 113 observations spanning from Mars Year 31 Ls = 291° (March 30, 2013) to Mars Year 33 Ls= 127° (March 24, 2016). Each ChemCam passive sky observation acquires spectra at two different elevation angles. We fit these spectra with a discrete-ordinates multiple scattering radiative transfer model, using the correlated-k approximation for gas absorption bands. The retrieval proceeds by first fitting the continuum of the ratio of the two elevation angles to solve for aerosol properties, and then fitting the continuum-removed ratio to solve for gas abundances. The final step of the retrieval makes use of the observed CO2 absorptions and the known CO2 abundance to correct the retrieved water vapor abundance for the effects of the vertical distribution of scattering aerosols and to derive an aerosol scale height parameter. Our water vapor results give water vapor column abundance with a precision of ±0.6 precipitable microns and systematic errors no larger than ±0.3 precipitable microns, assuming uniform vertical mixing. The ChemCam-retrieved water abundances show, with only a few exceptions, the same seasonal behavior and the same timing of seasonal minima and maxima as the TES, CRISM, and REMS-H data sets that we compare them to. However ChemCam-retrieved water abundances are generally lower than zonal and regional scale from-orbit water vapor data, while at the same time being significantly larger than pre-dawn REMS-H abundances. Pending further analysis of REMS-H volume mixing ratio uncertainties, the differences between ChemCam and REMS-H pre-dawn mixing ratios appear to be much too large to be explained by large scale circulations and thus

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

Directory of Open Access Journals (Sweden)

W. R. Sessions

2011-06-01

Full Text Available The Weather Research and Forecasting Model (WRF is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia.

One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and local atmospheric stability. This paper describes a case study of a 10 day period during the Spring phase of ARCTAS. It compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3–5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE. Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors.

When FLAMBE provides input to the 1-D plume rise model, the resulting injection heights exhibit the best agreement with satellite-observed injection heights. The FLAMBE-derived heights are more realistic than those utilizing prep_chem_sources. Conversely, when the planetary boundary layer or the 3–5 km a.g.l. layer were filled with emissions, the resulting injection heights exhibit less

Alkali trace elements in Gale crater, Mars, with ChemCam: Calibration update and geological implications

International Nuclear Information System (INIS)

Payre, Valerie; Fabre, Cecile; Cousin, Agnes; Sautter, Violaine; Wiens, Roger Craig

2017-01-01

The Chemistry Camera (ChemCam) instrument onboard Curiosity can detect minor and trace elements such as lithium, strontium, rubidium, and barium. Their abundances can provide some insights about Mars' magmatic history and sedimentary processes. We focus on developing new quantitative models for these elements by using a new laboratory database (more than 400 samples) that displays diverse compositions that are more relevant for Gale crater than the previous ChemCam database. These models are based on univariate calibration curves. For each element, the best model is selected depending on the results obtained by using the ChemCam calibration targets onboard Curiosity. New quantifications of Li, Sr, Rb, and Ba in Gale samples have been obtained for the first 1000 Martian days. Comparing these data in alkaline and magnesian rocks with the felsic and mafic clasts from the Martian meteorite NWA7533—from approximately the same geologic period—we observe a similar behavior: Sr, Rb, and Ba are more concentrated in soluble- and incompatible-element-rich mineral phases (Si, Al, and alkali-rich). Correlations between these trace elements and potassium in materials analyzed by ChemCam reveal a strong affinity with K-bearing phases such as feldspars, K-phyllosilicates, and potentially micas in igneous and sedimentary rocks. However, lithium is found in comparable abundances in alkali-rich and magnesium-rich Gale rocks. This very soluble element can be associated with both alkali and Mg-Fe phases such as pyroxene and feldspar. Here, these observations of Li, Sr, Rb, and Ba mineralogical associations highlight their substitution with potassium and their incompatibility in magmatic melts.

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 chemical...

The performance of the 'CentrifiChem' parallel fast analyser using packaged reagents.

Science.gov (United States)

Henry, P; Saunders, R A

1975-05-01

The CentrifiChem system was used with packaged reagent kits for the following determinations: albumin, alanine and aspartate aminotransferases, creatinine, glucose, and alpha-hydroxybutyrate and lactate dehydrogenases. The linearity obtainable for each assay was investigated, and particular attention was paid to finding the most suitable instrument settings.

77 FR 51503 - Endangered and Threatened Wildlife and Plants; Revisions to the Regulations for Impact Analyses...

Science.gov (United States)

2012-08-24

... impacts pursuant to New Mexico Cattlegrowers Ass'n v. FWS, 248 F.3d 1277 (10th Cir. 2001). The genesis of... incremental analysis approach in 2001 no longer applies. Arizona Cattle Growers Ass'n v. Salazar, 606 F.3d.... Supp. 2d 73 (D.D.C. 2010); Fisher v. Salazar, 656 F. Supp. 2d 1357 (N.D. Fla. 2009); Home Builders Ass...

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

International Nuclear Information System (INIS)

Wiens, Roger C.; Barraclough, Bruce; Barkley, Walter C.; Bender, Steve; Bernardin, John; Bultman, Nathan; Clanton, Robert C.; Clegg, Samuel; Delapp, Dorothea; Dingler, Robert; Enemark, Don; Flores, Mike; Hale, Thomas; Lanza, Nina; Lasue, Jeremie; Latino, Joseph; Little, Cynthia; Morrison, Leland; Nelson, Tony; Romero, Frank; Salazar, Steven; Stiglich, Ralph; Storms, Steven; Trujillo, Tanner; Ulibarri, Mike; Vaniman, David; Whitaker, Robert; Witt, James; Maurice, Sylvestre; Bouye, Marc; Cousin, Agnes; Cros, Alain; D'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Kouach, Driss; Lasue, Jeremie; Pares, Laurent; Poitrasson, Franck; Striebig, Nicolas; Thocaven, Jean-Jacques; Saccoccio, Muriel; Perez, Rene; Bell, James F. III; Hays, Charles; Blaney, Diana; DeFlores, Lauren; Elliott, Tom; Kan, Ed; Limonadi, Daniel; Lindensmith, Chris; Miller, Ed; Reiter, Joseph W.; Roberts, Tom; Simmonds, John J.; Warner, Noah; Blank, Jennifer; Bridges, Nathan; Cais, Phillippe; Clark, Benton; Cremers, David; Dyar, M. Darby; Fabre, Cecile; Herkenhoff, Ken; Kirkland, Laurel; Landis, David; Langevin, Yves; Lanza, Nina; Newsom, Horton; Ollila, Ann; LaRocca, Frank; Ott, Melanie; Mangold, Nicolas; Manhes, Gerard; Mauchien, Patrick; Blank, Jennifer; McKay, Christopher; Mooney, Joe; Provost, Cheryl; Morris, Richard V.; Sautter, Violaine; Sautter, Violaine; Waterbury, Rob; Wong-Swanson, Belinda; Barraclough, Bruce; Bender, Steve; Vaniman, David

2012-01-01

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)

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.

Modelling the urban air quality in Hamburg with the new city-scale chemistry transport model CityChem

Science.gov (United States)

Karl, Matthias; Ramacher, Martin; Aulinger, Armin; Matthias, Volker; Quante, Markus

2017-04-01

Air quality modelling plays an important role by providing guidelines for efficient air pollution abatement measures. Currently, most urban dispersion models treat air pollutants as passive tracer substances or use highly simplified chemistry when simulating air pollutant concentrations on the city-scale. The newly developed urban chemistry-transport model CityChem has the capability of modelling the photochemical transformation of multiple pollutants along with atmospheric diffusion to produce pollutant concentration fields for the entire city on a horizontal resolution of 100 m or even finer and a vertical resolution of 24 layers up to 4000 m height. CityChem is based on the Eulerian urban dispersion model EPISODE of the Norwegian Institute for Air Research (NILU). CityChem treats the complex photochemistry in cities using detailed EMEP chemistry on an Eulerian 3-D grid, while using simple photo-stationary equilibrium on a much higher resolution grid (receptor grid), i.e. close to industrial point sources and traffic sources. The CityChem model takes into account that long-range transport contributes to urban pollutant concentrations. This is done by using 3-D boundary concentrations for the city domain derived from chemistry-transport simulations with the regional air quality model CMAQ. For the study of the air quality in Hamburg, CityChem was set-up with a main grid of 30×30 grid cells of 1×1 km2 each and a receptor grid of 300×300 grid cells of 100×100 m2. The CityChem model was driven with meteorological data generated by the prognostic meteorology component of the Australian chemistry-transport model TAPM. Bottom-up inventories of emissions from traffic, industry, households were based on data of the municipality of Hamburg. Shipping emissions for the port of Hamburg were taken from the Clean North Sea Shipping project. Episodes with elevated ozone (O3) were of specific interest for this study, as these are associated with exceedances of the World

Identifying Known Unknowns Using the USEPA CompTox Chemistry Dashboard AnalytBioanlytChem Data

Data.gov (United States)

U.S. Environmental Protection Agency — In this research, the performance of the Dashboard for identifying “known unknowns” was evaluated against that of the online ChemSpider database, one of the primary...

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 (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. Ongoing efforts to model and correct for this dust component should improve calibration of the relative reflectance

Monotone numerical methods for finite-state mean-field games

KAUST Repository

Gomes, Diogo A.; Saude, Joao

2017-01-01

Here, we develop numerical methods for finite-state mean-field games (MFGs) that satisfy a monotonicity condition. MFGs are determined by a system of differential equations with initial and terminal boundary conditions. These non-standard conditions are the main difficulty in the numerical approximation of solutions. Using the monotonicity condition, we build a flow that is a contraction and whose fixed points solve the MFG, both for stationary and time-dependent problems. We illustrate our methods in a MFG modeling the paradigm-shift problem.

Monotone numerical methods for finite-state mean-field games

KAUST Repository

Gomes, Diogo A.

2017-04-29

Here, we develop numerical methods for finite-state mean-field games (MFGs) that satisfy a monotonicity condition. MFGs are determined by a system of differential equations with initial and terminal boundary conditions. These non-standard conditions are the main difficulty in the numerical approximation of solutions. Using the monotonicity condition, we build a flow that is a contraction and whose fixed points solve the MFG, both for stationary and time-dependent problems. We illustrate our methods in a MFG modeling the paradigm-shift problem.

Aerosol comparisons between sunphotometry / sky radiometry and the GEOS-Chem model

Science.gov (United States)

Chaubey, J. P.; Hesaraki, S.; O'Neill, N. T.; Saha, A.; Martin, R.; Lesins, G. B.; Abboud, I.

2014-12-01

Comparisons of aerosol optical depth (AOD), spectral AOD parameters and microphysical parameters derived from AEROCAN / AERONET sunphotometer / sky radiometer data acquired over Canada were compared with GEOS-Chem (Geos5,v9-01-03) estimations. The Canadian sites were selected so as to encompass a representative variety of different aerosol types ranging from fine mode (submicron) pollution and smoke aerosols, coarse mode (supermicron) dust, fine and coarse mode marine aerosols, volcanic (fine mode) sulfates and volcanic (coarse mode) ash, etc). A particular focus was placed on comparisons at remote Canadian sites with a further focus on Arctic sites. The analysis included meteorological-scale event comparisons as well as seasonal and yearly comparisons on a climatological scale. The investigations were given a further aerosol type context by comparing optical retrievals of fine and coarse mode AOD with the AODs of the different aerosol types predicted by GEOS-Chem. The effects of temporal and spectral cloud screening of the sunphotometer data on the quality and robustness of these comparisons was the object of an important supporting investigation. The results of this study will be presented for a 3 year period from 2009 to 2011.

Soil diversity and hydration as observed by ChemCam at Gale Crater, Mars

NARCIS (Netherlands)

Meslin, P.-Y.; Gasnault, O.; Forni, O.; Schröder, 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.; Mangold, N.; Ehlmann, B.; Lanza, N.; Harri, A.-M.; Anderson, R.; Rampe, E.; McConnochie, T.H.; Pinet, P.; Blaney, D.; Léveillé, R.; 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.; Gondet, B.; Grotzinger, J.; Herkenhoff, K.; Johnson, J.; Lacour, J.-L.; Langevin, Y.; Leshin, L.; Lewin, E.; Madsen, M.B.; Melikechi, N.; Mezzacappa, A.; Mischna, M.A.; Moores, J.E.; Newsom, H.; Ollila, A.; Perez, R.; Renno, N.; Sirven, J.-B.; Tokar, R.; De La Torre, M.; D'Uston, L.; Vaniman, D.; Yingst, A.; MSL Science Team, the

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

Calibration of the MSL/ChemCam/LIBS Remote Sensing Composition Instrument

Science.gov (United States)

Wiens, R. C.; Maurice S.; Bender, S.; Barraclough, B. L.; Cousin, A.; Forni, O.; Ollila, A.; Newsom, H.; Vaniman, D.; Clegg, S.;

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...... evaluation of environmental chemicals, natural products and approved drugs, as well as the selection of new compounds based on their activity profile against most known biological targets, including those related to adverse drug events. Results from the disease chemical biology database associate citalopram...

Nanoplatforms for Detection, Remediation and Protection Against Chem-Bio Warfare

Science.gov (United States)

Denkbaş, E. B.; Bayram, C.; Kavaz, D.; Çirak, T.; Demirbilek, M.

Chemical and biological substances have been used as warfare agents by terrorists by varying degree of sophistication. It is critical that these agents be detected in real-time with high level of sensitively, specificity, and accuracy. Many different types of techniques and systems have been developed to detect these agents. But there are some limitations in these conventional techniques and systems. Limitations include the collection, handling and sampling procedures, detection limits, sample transfer, expensive equipment, personnel training, and detection materials. Due to the unique properties such as quantum effect, very high surface/volume ratio, enhanced surface reactivity, conductivity, electrical and magnetic properties of the nanomaterials offer great opportunity to develop very fast, sensitive, accurate and cost effective detection techniques and systems to detect chemical and biological (chem.-bio) warfare agents. Furthermore, surface modification of the materials is very easy and effective way to get functional or smart surfaces to be used as nano-biosensor platform. In that respect many different types of nanomaterials have been developed and used for the detection, remediation and protection, such as gold and silver nanoparticles, quantum dots, Nano chips and arrays, fluorescent polymeric and magnetic nanoparticles, fiber optic and cantilever based nanobiosensors, nanofibrillar nanostructures etc. This study summarizes preparation and characterization of nanotechnology based approaches for the detection of and remediation and protection against chem.-bio warfare agents.

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.

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)

SOUTHWELL, EDWIN T.; GARCIA, MARIE L.; MEYERS, CHARLES E.

2001-01-01

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

The simulator Neck-Mfgs and its training status

International Nuclear Information System (INIS)

Setnikar, T.; Pribozic, F.; Srebotnjak, E.; Gortnar, O.; Kovacic, J.; Stritar, A.

1998-01-01

This paper presents the status and training possibilities on Krsko NPP Multi-Functional Simulator (NEK-MFS). Since spring 1997 it serves as a training facility in Nuclear Training Center. During first year of operation the simulator NEK-MFS was found to be a very useful Krsko NPP specific tool which is capable to support both the initial operator training program and licensed operator retraining activities.(author)

PREDIKSI SEBARAN ASAP KEBAKARAN HUTAN/LAHAN MENGGUNAKAN WRF/CHEM (Studi Kasus: Tanggal 14 dan 20 Juni 2012, Pekanbaru-Riau

Directory of Open Access Journals (Sweden)

Eko Heriyanto

2015-01-01

Full Text Available Penelitian ini bertujuan mengembangkan prediksi sebaran asap kebakaran hutan/lahan di wilayah Indonesia. Simulasi prediksi sebaran  asap (hindcast menggunakan model Weather Research and Forecasting with CHEMistry (WRF/CHEM pada kasus kebakaran hutan/lahan tanggal 14 dan 20 Juni 2012 di wilayah Pekanbaru-Riau. Dalam penelitian ini digunakan data luaran WRF resolusi 25 km dan emisi global . Hasil simulasi  konsentrasi Carbon Monoxide (CO luaran WRF/CHEM menggambarkan pola yang identik dengan hasil luaran Monitoring Atmospheric Composition and Climate (MACC-Reanalysis 1.10. Dilakukan juga analisis kualitatif terhadap hasil simulasi kedua model dengan citra satelit Aqua-Terra MODIS, NOAA-18, dan total column CO Atmospheric Infrared Sounder (AIRS dari NASA. Korelasi simulasi kedua model menunjukkan nilai yang baik antara 0.55 – 0.83. Secara umum dapat disimpulkan bahwa WRF/CHEM mampu mensimulasikan sebaran asap kebakaran hutan/lahan secara akurat. Hasil penelitian ini bisa menjadi salah satu langkah awal dalam pengembangan sistem peringatan dini sebaran asap kebakaran hutan/lahan di wilayah Indonesia.   This study aims to develop a predictive distribution of forest fire smoke/land in the territory of Indonesia. The simulation of smoke spread prediction (hindcast is using the Weather Research and Forecasting Model with CHEMistry (WRF/CHEM in the case of forest fires/land dated June 14, 2012 in Pekanbaru-Riau region. This study uses the WRF data output resolution 25 km and global emissions. Carbon Monoxide concentration simulation results (CO which is the WRF/CHEM output describes patterns that are identical to the results of Monitoring Atmospheric Composition and Climate (MACC-Reanalysis 1.1250 outcomes. a qualitative analysis of the results of the both simulation models with satellite imagery MODIS Aqua-Terra,NOAA-18 and the Total column CO Atmospheric Infrared Sounder (Airs from NASA has  been conducted as well. Both simulation models show a

iNR-PhysChem: a sequence-based predictor for identifying nuclear receptors and their subfamilies via physical-chemical property matrix.

Directory of Open Access Journals (Sweden)

Xuan Xiao

Full Text Available Nuclear receptors (NRs form a family of ligand-activated transcription factors that regulate a wide variety of biological processes, such as homeostasis, reproduction, development, and metabolism. Human genome contains 48 genes encoding NRs. These receptors have become one of the most important targets for therapeutic drug development. According to their different action mechanisms or functions, NRs have been classified into seven subfamilies. With the avalanche of protein sequences generated in the postgenomic age, we are facing the following challenging problems. Given an uncharacterized protein sequence, how can we identify whether it is a nuclear receptor? If it is, what subfamily it belongs to? To address these problems, we developed a predictor called iNR-PhysChem in which the protein samples were expressed by a novel mode of pseudo amino acid composition (PseAAC whose components were derived from a physical-chemical matrix via a series of auto-covariance and cross-covariance transformations. It was observed that the overall success rate achieved by iNR-PhysChem was over 98% in identifying NRs or non-NRs, and over 92% in identifying NRs among the following seven subfamilies: NR1--thyroid hormone like, NR2--HNF4-like, NR3--estrogen like, NR4--nerve growth factor IB-like, NR5--fushi tarazu-F1 like, NR6--germ cell nuclear factor like, and NR0--knirps like. These rates were derived by the jackknife tests on a stringent benchmark dataset in which none of protein sequences included has ≥60% pairwise sequence identity to any other in a same subset. As a user-friendly web-server, iNR-PhysChem is freely accessible to the public at either http://www.jci-bioinfo.cn/iNR-PhysChem or http://icpr.jci.edu.cn/bioinfo/iNR-PhysChem. Also 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 involved in developing the predictor. It is anticipated that iNR-PhysChem may

Existence of weak solutions to first-order stationary mean-field games with Dirichlet conditions

KAUST Repository

Ferreira, Rita; Gomes, Diogo A.; Tada, Teruo

2018-01-01

In this paper, we study first-order stationary monotone mean-field games (MFGs) with Dirichlet boundary conditions. While for Hamilton--Jacobi equations Dirichlet conditions may not be satisfied, here, we establish the existence of solutions of MFGs that satisfy those conditions. To construct these solutions, we introduce a monotone regularized problem. Applying Schaefer's fixed-point theorem and using the monotonicity of the MFG, we verify that there exists a unique weak solution to the regularized problem. Finally, we take the limit of the solutions of the regularized problem and using Minty's method, we show the existence of weak solutions to the original MFG.

ConfChem Conference on Flipped Classroom: Using a Blog to Flip a Classroom

Science.gov (United States)

Haile, January D.

2015-01-01

This communication summarizes one of the invited papers to the Flipped Classroom ACS Division of Chemical Education Committee on Computers in Chemical Education online ConfChem held from May 18 to June 24, 2014. Just in Time Teaching is a technique in which students read the material before class and respond to a few questions. In a first-year…

E-chem page: A Support System for Remote Diagnosis of Water Quality in Boiling Water Reactors

International Nuclear Information System (INIS)

Naohiro Kusumi; Takayasu Kasahara; Kazuhiko Akamine; Kenji Tada; Naoshi Usui; Nobuyuki Oota

2002-01-01

It is important to control and maintain water quality for nuclear power plants. Chemical engineers sample and monitor reactor water from various subsystems and analyze the chemical quality as routine operations. With regard to controlling water quality, new technologies have been developed and introduced to improve the water quality from both operation and material viewpoints. To maintain the quality, it is important to support chemical engineers in evaluating the water quality and realizing effective retrieval of stored data and documents. We have developed a remote support system using the Internet to diagnose BWR water quality, which we call e-chem page. The e-chem page integrates distributed data and information in a Web server, and makes it easy to evaluate the data on BWR water chemistry. This system is composed of four functions: data transmission, water quality evaluation, inquiry and history retrieval system, and reference to documents on BWR water chemistry. The developed system is now being evaluated in trial operations by Hitachi, Ltd. and an electric power company. In addition diagnosis technology applying independent component analysis (ICA) is being developed to improve predictive capability of the system. This paper describes the structure and function of the e-chem page and presents results of obtained with the proposed system for the prediction of chemistry conditions in reactor water. (authors)

Air Quality Modeling for the Urban Jackson, Mississippi Region Using a High Resolution WRF/Chem Model

Directory of Open Access Journals (Sweden)

Shelton J. Swanier

2011-06-01

Full Text Available In this study, an attempt was made to simulate the air quality with reference to ozone over the Jackson (Mississippi region using an online WRF/Chem (Weather Research and Forecasting–Chemistry model. The WRF/Chem model has the advantages of the integration of the meteorological and chemistry modules with the same computational grid and same physical parameterizations and includes the feedback between the atmospheric chemistry and physical processes. The model was designed to have three nested domains with the inner-most domain covering the study region with a resolution of 1 km. The model was integrated for 48 hours continuously starting from 0000 UTC of 6 June 2006 and the evolution of surface ozone and other precursor pollutants were analyzed. The model simulated atmospheric flow fields and distributions of NO2 and O3 were evaluated for each of the three different time periods. The GIS based spatial distribution maps for ozone, its precursors NO, NO2, CO and HONO and the back trajectories indicate that all the mobile sources in Jackson, Ridgeland and Madison contributing significantly for their formation. The present study demonstrates the applicability of WRF/Chem model to generate quantitative information at high spatial and temporal resolution for the development of decision support systems for air quality regulatory agencies and health administrators.

PubChemQC Project: A Large-Scale First-Principles Electronic Structure Database for Data-Driven Chemistry.

Science.gov (United States)

Nakata, Maho; Shimazaki, Tomomi

2017-06-26

Large-scale molecular databases play an essential role in the investigation of various subjects such as the development of organic materials, in silico drug design, and data-driven studies with machine learning. We have developed a large-scale quantum chemistry database based on first-principles methods. Our database currently contains the ground-state electronic structures of 3 million molecules based on density functional theory (DFT) at the B3LYP/6-31G* level, and we successively calculated 10 low-lying excited states of over 2 million molecules via time-dependent DFT with the B3LYP functional and the 6-31+G* basis set. To select the molecules calculated in our project, we referred to the PubChem Project, which was used as the source of the molecular structures in short strings using the InChI and SMILES representations. Accordingly, we have named our quantum chemistry database project "PubChemQC" ( http://pubchemqc.riken.jp/ ) and placed it in the public domain. In this paper, we show the fundamental features of the PubChemQC database and discuss the techniques used to construct the data set for large-scale quantum chemistry calculations. We also present a machine learning approach to predict the electronic structure of molecules as an example to demonstrate the suitability of the large-scale quantum chemistry database.

ChemCam at Gale Crater: Highlights and Discoveries from Three Years of Chemical Measurements on Mars

Science.gov (United States)

Blaney, Diana L.; Wiens, Roger; Maurice, Sylvestre; Gasnault, Olivier; Anderson, Ryan; Bridges, John; Bridges, Nathan; Clegg, Samuel; Clark, Benton; Ehlmann, Bethany; Dyar, Melinda D.; Fisk, Martin; Francis, Raymond; Fabre, Cecile; Forni, Olivier; Frydenvang, Jens; Johnson, Jeffery; Lanza, Nina; Leveille, Richard; Lasue, Jeremie; Le Deit, Laetitia; Mangold, Nicholas; Melikechi, Noureddine; Nachon, Marion; Newsom, Horton; Payre, Valerie; Rapin, William; Sautter, Violane; Vaniman, David; Grotzinger, John; Vasavad, Ashwin; Crisp, Joy

2015-11-01

ChemCam has undertaken a detailed chemical investigation of the rocks and soils at Gale crater over the last three years with over six thousand separate geochemical measurements. Recent recalibration of the ChemCam data using a new library of >350 geochemical standards has enabled increased elemental accuracies over a wider compositional range. The increased accuracy combined with ChemCam’s small spot size allows for the chemistry of mineral end members including feldspars, high silica, oxide rich grains to be identified. ChemCam has observed both sedimentary and igneous compositions. Igneous compositions are generally present in conglomerates and in float rocks. Compositions show a wide range of igneous chemistry ranging from basaltic to feldspar rich assemblages.Sedimentary rocks have a wide range of compositions reflecting both differences in chemical source regions and in depositional and diagenetic histories. The “Sheepbed” mudstones cluster around Martian average crustal compositions. The “Kimberley” outcrop showed enhanced potassium reaching concentrations up to ~6 wt% K2O. More recent observations in the Murray Formation at the base of Mt. Sharp reveal mudstones that are lower in magnesium and higher in silica and aluminum than the more basaltic mudstones previously investigated. Extremely high silica (75-85 wt%) deposits have also been identified. The high silica observations were associated with increased TiO2, While the Murray mudstones are generally low in magnesium, local enhancements in magnesium have also been noted associated with resistant facies in the outcrop. Chemical trends also indicate that iron oxide phases may also be present as cements. Sandstone facies with a mafic composition are also present. Veins in the unit also show a wide range of compositions indicating fluid chemistries rich in calcium sulfate, fluorine, magnesium and iron were present. Vein chemistry could be the result of distinct fluids migrating through from a

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.;

The Chem-E-Car as a Vehicle for Service Learning through K-12 Outreach

Science.gov (United States)

Chirdon, William

2017-01-01

This article presents the results of combining the American Institute of Chemical Engineers' (AIChE) Chem-E-Car competition activities with engineering outreach to K-12 students in a service-learning course. Survey results are presented to show how the program develops technical skills as well as leadership, teamwork, and communication skills in…

Rozhovor s Jiřím Poláchem a Michaelou Záluskou z Knihovny ÚOCHB

Czech Academy of Sciences Publication Activity Database

Burešová, Iva

2-3 (2016) E-ISSN 1805-2800 Keywords : interview * Institute of Organic Chemistry and Biochemistry of the CAS * library tramformation * chemLib https://www.lib.cas.cz/casopis-informace/knihovna-uochb/

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)

Existence of weak solutions to first-order stationary mean-field games with Dirichlet conditions

KAUST Repository

Ferreira, Rita

2018-04-19

In this paper, we study first-order stationary monotone mean-field games (MFGs) with Dirichlet boundary conditions. While for Hamilton--Jacobi equations Dirichlet conditions may not be satisfied, here, we establish the existence of solutions of MFGs that satisfy those conditions. To construct these solutions, we introduce a monotone regularized problem. Applying Schaefer\\'s fixed-point theorem and using the monotonicity of the MFG, we verify that there exists a unique weak solution to the regularized problem. Finally, we take the limit of the solutions of the regularized problem and using Minty\\'s method, we show the existence of weak solutions to the original MFG.

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

International Nuclear Information System (INIS)

2009-01-01

Book of Abstracts contains short descriptions of presentations 3 lectures and 105 posters presented during ChemSession'09 - 6 th 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

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

Correcting for variable laser-target distances of laser-induced breakdown spectroscopy measurements with ChemCam using emission lines of Martian dust spectra

Energy Technology Data Exchange (ETDEWEB)

Melikechi, N.; Mezzacappa, A. [Optical Science Center for Applied Research, Delaware State University, Dover, DE (United States); Cousin, A.; Lanza, N.L. [Los Alamos National Laboratory, Los Alamos, NM (United States); Lasue, J. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Clegg, S.M. [Los Alamos National Laboratory, Los Alamos, NM (United States); Berger, G. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Wiens, R.C. [Los Alamos National Laboratory, Los Alamos, NM (United States); Maurice, S. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Tokar, R.L.; Bender, S. [Planetary Science Institute, Flagstaff, AZ (United States); Forni, O. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Breves, E.A.; Dyar, M.D. [Dept. of Astronomy, Mount Holyoke College, South Hadley, MA (United States); Frydenvang, J. [The Niels Bohr Institute, University of Copenhagen, Copenhagen (Denmark); Delapp, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Gasnault, O. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Newsom, H.; Ollila, A.M. [Earth and Planetary Sciences, University of New Mexico, Alburquerque, NM (United States); Lewin, E. [Institut des Sciences de la Terre, Universite Grenoble l-CNRS, Grenoble (France); and others

2014-06-01

As part of the Mars Science Laboratory, the ChemCam instrument acquires remote laser induced breakdown spectra at distances that vary between 1.56 m and 7 m. This variation in distance affects the intensities of the measured LIBS emission lines in non-trivial ways. To determine the behavior of a LIBS emission line with distance, it is necessary to separate the effects of many parameters such as laser energy, laser spot size, target homogeneity, and optical collection efficiency. These parameters may be controlled in a laboratory on Earth but for field applications or in space this is a challenge. In this paper, we show that carefully selected ChemCam LIBS emission lines acquired from the Martian dust can be used to build an internal proxy spectroscopic standard. This in turn, allows for a direct measurement of the effects of the distance of various LIBS emission lines and hence can be used to correct ChemCam LIBS spectra for distance variations. When tested on pre-launch LIBS calibration data acquired under Martian-like conditions and with controlled and well-calibrated targets, this approach yields much improved agreement between targets observed at various distances. This work lays the foundation for future implementation of automated routines to correct ChemCam spectra for differences caused by variable distance. - Highlights: • Selected Martian dust emission lines are used to correct for variable laser-target distances. • The correction model yields improved agreement between targets observed at various distances. • The impact of the model reduces the bias between predicted and actual compositions by as much as 70%. • When implemented, the model will yield spectral corrections for various ChemCam measurements. • This work is a foundation to perform novel stand-off LIBS measurements on Earth and other planets.

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

International Nuclear Information System (INIS)

Madura, I.

2008-01-01

Book of Abstracts consists of short descriptions of presentations: 5 lectures and 127 posters presented during ChemSession'08 - 5 th 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

Mixed Waste Treatment Using the ChemChar Thermolytic Detoxification Technique

International Nuclear Information System (INIS)

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

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.

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

International Nuclear Information System (INIS)

Madura, I.

2010-01-01

Book of Abstracts contains short descriptions of presentations 4 lectures and 151 posters presented during ChemSession'10 - 7 th 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.

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

Diversity of Rock Compositions at Gale Crater Observed by ChemCam and APXS on Curiosity, and Comparison to Meteorite and Orbital Observations

Science.gov (United States)

Wiens, R. C.; Maurice, S.; Grotzinger, J. P.; Gellert, R.; Mangold, N.; Sautter, V.; Ollila, A.; Dyar, M. D.; Le Mouelic, S.; Ehlmann, B. L.; Clegg, S. M.; Lanza, N.; Cousin, A.; Forni, O.; Gasnault, O.; Lasue, J.; Blaney, D. L.; Newsom, H. E.; Herkenhoff, K. E.; Anderson, R. B.; D'Uston, L.; Bridges, N. T.; Fabre, C.; Meslin, P.; Johnson, J.; Vaniman, D.; Bridges, J.; Dromart, G.; Schmidt, M. E.; Team, M.

2013-12-01

Gale crater was selected as the Curiosity landing site because of the apparent sedimentary spectral signatures seen from orbit. Sedimentary materials on Mars have to this point showed very little expression of major element mobility, so compositions of precursor igneous minerals play a strong role in the compositions of sediments. In addition, pebbles and float rocks on Bradbury Rise (sols 0-50, > 324) appear to be mostly igneous in origin, and are assumed to have been carried down from the crater rim. Overall in the first year on Mars ChemCam obtained >75,000 LIBS spectra on > 2,000 observation points, supported by > 1,000 RMI images, and APXS obtained a significant number of observations. These show surprisingly variable compositions. The mean ChemCam compositions for Bradbury Rise dust-free rocks and pebbles (62 locations) give SiO2 = 56%, FeOT = 16% and show high alkalis consistent with Jake Matijevic (sol ~47) APXS Na2O ~6.6 wt%. ChemCam observations on the conglomerate Link (sol 27) gave Rb > 150 ppm and Sr > 1500 ppm. These compositions imply the presence of abundant alkali feldspars in the material infilling the lower parts of Gale crater. They are generally consistent with the more feldspar-rich SNC meteorites but show a radical departure from larger scale orbital observations, e.g., GRS, raising the question of how widespread these compositions are outside of Gale crater. Sedimentary materials at Yellowknife Bay encompassing the Sheepbed (sols 125-300) and Shaler (sols 121, 311-324) units, potentially including Point Lake (sols 301-310) and Rocknest (sols 57-97), appear to have incorporated varying amounts of igneous source materials. Seven rocks investigated at Rocknest show significant additions of Fe, with mean FeOT = 25% (154 locations), suggesting that FeO was a cementing agent. ChemCam observations at Shaler show varying amounts of alkali feldspar (i.e., related to Bradbury Rise), Fe-rich material (Rocknest-like), and potassium-rich material

FastChem: A computer program for efficient complex chemical equilibrium calculations in the neutral/ionized gas phase with applications to stellar and planetary atmospheres

Science.gov (United States)

Stock, Joachim W.; Kitzmann, Daniel; Patzer, A. Beate C.; Sedlmayr, Erwin

2018-06-01

For the calculation of complex neutral/ionized gas phase chemical equilibria, we present a semi-analytical versatile and efficient computer program, called FastChem. The applied method is based on the solution of a system of coupled nonlinear (and linear) algebraic equations, namely the law of mass action and the element conservation equations including charge balance, in many variables. Specifically, the system of equations is decomposed into a set of coupled nonlinear equations in one variable each, which are solved analytically whenever feasible to reduce computation time. Notably, the electron density is determined by using the method of Nelder and Mead at low temperatures. The program is written in object-oriented C++ which makes it easy to couple the code with other programs, although a stand-alone version is provided. FastChem can be used in parallel or sequentially and is available under the GNU General Public License version 3 at https://github.com/exoclime/FastChem together with several sample applications. The code has been successfully validated against previous studies and its convergence behavior has been tested even for extreme physical parameter ranges down to 100 K and up to 1000 bar. FastChem converges stable and robust in even most demanding chemical situations, which posed sometimes extreme challenges for previous algorithms.

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

Directory of Open Access Journals (Sweden)

G. Grell

2011-06-01

Full Text Available 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 inclusion of the intense wildfires of the 2004 fire season in the model simulations, the interaction of the aerosols with the atmospheric radiation led to significant modifications of vertical profiles of temperature and moisture in cloud-free areas. On the other hand, when clouds were present, the high concentrations of fine aerosol (PM_2.5 and the resulting large numbers of Cloud Condensation Nuclei (CCN had a strong impact on clouds and cloud microphysics, with decreased precipitation coverage and precipitation amounts during the first 12 h of the integration. During the afternoon, storms were of convective nature and appeared significantly stronger, probably as a result of both the interaction of aerosols with radiation (through an increase in CAPE as well as the interaction with cloud microphysics.

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

International Nuclear Information System (INIS)

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

2014-01-01

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. - 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

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

International Nuclear Information System (INIS)

Madura, I.

2011-01-01

Book of Abstracts contains short descriptions of presentations: 4 lectures, 1 communication and 149 posters presented during ChemSession'11 - 8 th 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.

Operational forecast products and applications based on WRF/Chem

Science.gov (United States)

Hirtl, Marcus; Flandorfer, Claudia; Langer, Matthias; Mantovani, Simone; Olefs, Marc; Schellander-Gorgas, Theresa

2015-04-01

The responsibilities of the national weather service of Austria (ZAMG) include the support of the federal states and the public in questions connected to the protection of the environment in the frame of advisory and counseling services as well as expert opinions. The ZAMG conducts daily Air-Quality forecasts using the on-line coupled model WRF/Chem. The mother domain expands over Europe, North Africa and parts of Russia. The nested domain includes the alpine region and has a horizontal resolution of 4 km. Local emissions (Austria) are used in combination with European inventories (TNO and EMEP) for the simulations. The modeling system is presented and the results from the evaluation of the assimilation of pollutants using the 3D-VAR software GSI is shown. Currently observational data (PM10 and O3) from the Austrian Air-Quality network and from European stations (EEA) are assimilated into the model on an operational basis. In addition PM maps are produced using Aerosol Optical Thickness (AOT) observations from MODIS in combination with model data using machine learning techniques. The modeling system is operationally evaluated with different data sets. The emphasis of the application is on the forecast of pollutants which are compared to the hourly values (PM10, O3 and NO2) of the Austrian Air-Quality network. As the meteorological conditions are important for transport and chemical processes, some parameters like wind and precipitation are automatically evaluated (SAL diagrams, maps, …) with other models (e.g. ECMWF, AROME, …) and ground stations via web interface. The prediction of the AOT is also important for operators of solar power plants. In the past Numerical Weather Prediction (NWP) models were used to predict the AOT based on cloud forecasts at the ZAMG. These models do not consider the spatial and temporal variation of the aerosol distribution in the atmosphere with a consequent impact on the accuracy of forecasts especially during clear-sky days

WRF and WRF-Chem v3.5.1 simulations of meteorology and black carbon concentrations in the Kathmandu Valley

Directory of Open Access Journals (Sweden)

A. Mues

2018-06-01

Full Text Available An evaluation of the meteorology simulated using the Weather Research and Forecast (WRF model for the region of south Asia and Nepal with a focus on the Kathmandu Valley is presented. A particular focus of the model evaluation is placed on meteorological parameters that are highly relevant to air quality such as wind speed and direction, boundary layer height and precipitation. The same model setup is then used for simulations with WRF including chemistry and aerosols (WRF-Chem. A WRF-Chem simulation has been performed using the state-of-the-art emission database, EDGAR HTAP v2.2, which is the Emission Database for Global Atmospheric Research of the Joint Research Centre (JRC of the European Commission, in cooperation with the Task Force on Hemispheric Transport of Air Pollution (TF HTAP organized by the United Nations Economic Commission for Europe, along with a sensitivity simulation using observation-based black carbon emission fluxes for the Kathmandu Valley. The WRF-Chem simulations are analyzed in comparison to black carbon measurements in the valley and to each other.The evaluation of the WRF simulation with a horizontal resolution of 3×3 km2 shows that the model is often able to capture important meteorological parameters inside the Kathmandu Valley and the results for most meteorological parameters are well within the range of biases found in other WRF studies especially in mountain areas. But the evaluation results also clearly highlight the difficulties of capturing meteorological parameters in such complex terrain and reproducing subgrid-scale processes with a horizontal resolution of 3×3 km2. The measured black carbon concentrations are typically systematically and strongly underestimated by WRF-Chem. A sensitivity study with improved emissions in the Kathmandu Valley shows significantly reduced biases but also underlines several limitations of such corrections. Further improvements of the model and of the emission data are

The ChemChar process for hazardous-waste treatment

International Nuclear Information System (INIS)

McGowin, A.E.

1991-01-01

The ChemChar Reverse-Burn Gasification Process has been studied for application to the thermal destruction of radioactive waste organic ion exchange resins. The resulting char was mixed with cement to form a dry, leach-resistant final disposal product. Successful regeneration of spent granular activated carbons was achieved with reverse-burn gasification. Regeneration parameters such as moisture content and supplemental fuel addition were investigated. The performance of regenerated carbon was evaluated by batch equilibrium and breakthrough assay and was comparable to that of the original. Surface areas were determined by the BET method. The fate of mercury during reverse-burn gasification was investigated. TRB Char adsorbent was used to remove mercury vapor emission from the process. The use of petroleum coke as a substrate for gasification of wastes was studied. Petroleum coke was activated by reverse-burn gasification to produce a highly porous, low surface area solid. Destruction efficiency for hexachlorobenzene on activated coke was considerably lower than on coal char, however, the addition of iron appeared to catalyze hexachlorobenzene gasification

In situ detection of boron by ChemCam on Mars

Science.gov (United States)

Gasda, Patrick J.; Haldeman, Ethan B.; Wiens, Roger C.; Rapin, William; Bristow, Thomas F.; Bridges, John C.; Schwenzer, Susanne P.; Clark, Benton; Herkenhoff, Kenneth; Frydenvang, Jens; Lanza, Nina L.; Maurice, Sylvestre; Clegg, Samuel; Delapp, Dorothea M.; Sanford, Veronica L.; Bodine, Madeleine R.; McInroy, Rhonda

2017-09-01

We report the first in situ detection of boron on Mars. Boron has been detected in Gale crater at levels Curiosity rover ChemCam instrument in calcium-sulfate-filled fractures, which formed in a late-stage groundwater circulating mainly in phyllosilicate-rich bedrock interpreted as lacustrine in origin. We consider two main groundwater-driven hypotheses to explain the presence of boron in the veins: leaching of borates out of bedrock or the redistribution of borate by dissolution of borate-bearing evaporite deposits. Our results suggest that an evaporation mechanism is most likely, implying that Gale groundwaters were mildly alkaline. On Earth, boron may be a necessary component for the origin of life; on Mars, its presence suggests that subsurface groundwater conditions could have supported prebiotic chemical reactions if organics were also present and provides additional support for the past habitability of Gale crater.

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

Comment on ``On the Crooks fluctuation theorem and the Jarzynski equality'' [J. Chem. Phys. 129, 091101 (2008)

Science.gov (United States)

Adib, Artur B.

2009-06-01

It has recently been argued that a self-consistency condition involving the Jarzynski equality (JE) and the Crooks fluctuation theorem (CFT) is violated for a simple Brownian process [L. Y. Chen, J. Chem. Phys.129, 091101 (2008)]. This note adopts the definitions in the original formulation of the JE and CFT and demonstrates the contrary.

Exploring Natural Products from the Biodiversity of Pakistan for Computational Drug Discovery Studies: Collection, Optimization, Design and Development of A Chemical Database (ChemDP).

Science.gov (United States)

Mirza, Shaher Bano; Bokhari, Habib; Fatmi, Muhammad Qaiser

2015-01-01

Pakistan possesses a rich and vast source of natural products (NPs). Some of these secondary metabolites have been identified as potent therapeutic agents. However, the medicinal usage of most of these compounds has not yet been fully explored. The discoveries for new scaffolds of NPs as inhibitors of certain enzymes or receptors using advanced computational drug discovery approaches are also limited due to the unavailability of accurate 3D structures of NPs. An organized database incorporating all relevant information, therefore, can facilitate to explore the medicinal importance of the metabolites from Pakistani Biodiversity. The Chemical Database of Pakistan (ChemDP; release 01) is a fully-referenced, evolving, web-based, virtual database which has been designed and developed to introduce natural products (NPs) and their derivatives from the biodiversity of Pakistan to Global scientific communities. The prime aim is to provide quality structures of compounds with relevant information for computer-aided drug discovery studies. For this purpose, over 1000 NPs have been identified from more than 400 published articles, for which 2D and 3D molecular structures have been generated with a special focus on their stereochemistry, where applicable. The PM7 semiempirical quantum chemistry method has been used to energy optimize the 3D structure of NPs. The 2D and 3D structures can be downloaded as .sdf, .mol, .sybyl, .mol2, and .pdb files - readable formats by many chemoinformatics/bioinformatics software packages. Each entry in ChemDP contains over 100 data fields representing various molecular, biological, physico-chemical and pharmacological properties, which have been properly documented in the database for end users. These pieces of information have been either manually extracted from the literatures or computationally calculated using various computational tools. Cross referencing to a major data repository i.e. ChemSpider has been made available for overlapping

An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

OpenAIRE

W. R. Sessions; H. E. Fuelberg; R. A. Kahn; D. M. Winker

2010-01-01

The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia.

ChemEngine: harvesting 3D chemical structures of supplementary data from PDF files.

Science.gov (United States)

Karthikeyan, Muthukumarasamy; Vyas, Renu

2016-01-01

Digital access to chemical journals resulted in a vast array of molecular information that is now available in the supplementary material files in PDF format. However, extracting this molecular information, generally from a PDF document format is a daunting task. Here we present an approach to harvest 3D molecular data from the supporting information of scientific research articles that are normally available from publisher's resources. In order to demonstrate the feasibility of extracting truly computable molecules from PDF file formats in a fast and efficient manner, we have developed a Java based application, namely ChemEngine. This program recognizes textual patterns from the supplementary data and generates standard molecular structure data (bond matrix, atomic coordinates) that can be subjected to a multitude of computational processes automatically. The methodology has been demonstrated via several case studies on different formats of coordinates data stored in supplementary information files, wherein ChemEngine selectively harvested the atomic coordinates and interpreted them as molecules with high accuracy. The reusability of extracted molecular coordinate data was demonstrated by computing Single Point Energies that were in close agreement with the original computed data provided with the articles. It is envisaged that the methodology will enable large scale conversion of molecular information from supplementary files available in the PDF format into a collection of ready- to- compute molecular data to create an automated workflow for advanced computational processes. Software along with source codes and instructions available at https://sourceforge.net/projects/chemengine/files/?source=navbar.Graphical abstract.

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

Science.gov (United States)

Jourdain, L.; Kulawik, S. S.; Worden, H. M.; Pickering, K. E.; Worden, J.; Thompson, A. M.

2010-01-01

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.

Exploration of Mars with the ChemCam LIBS Instrument and the Curiosity Rover

Science.gov (United States)

Newsom, Horton E.

2016-01-01

The Mars Science Laboratory (MSL) Curiosity rover landed on Mars in August 2012, and has been exploring the planet ever since. Dr. Horton E. Newsom will discuss the MSL's design and main goal, which is to characterize past environments that may have been conducive to the evolution and sustainability of life. He will also discuss Curiosity's science payload, and remote sensing, analytical capabilities, and direct discoveries of the Chemistry & Camera (ChemCam) instrument, which is the first Laser Induced Breakdown Spectrometer (LIBS) to operate on another planetary surface and determine the chemistry of the rocks and soils.

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

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

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. 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.

Weakly coupled mean-field game systems

KAUST Repository

Gomes, Diogo A.; Patrizi, Stefania

2016-01-01

Here, we prove the existence of solutions to first-order mean-field games (MFGs) arising in optimal switching. First, we use the penalization method to construct approximate solutions. Then, we prove uniform estimates for the penalized problem

Explicit Solutions for One-Dimensional Mean-Field Games

KAUST Repository

Prazeres, Mariana

2017-01-01

In this thesis, we consider stationary one-dimensional mean-field games (MFGs) with or without congestion. Our aim is to understand the qualitative features of these games through the analysis of explicit solutions. We are particularly interested

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

Energy Technology Data Exchange (ETDEWEB)

Michalewicz, M.T. [CSIRO, Supercomputing Support Group, Carlton, VIC (Australia). Division of Information Technology; Winkler, D.A. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Clayton, VIC (Australia). Div. of Chemical Physics; Brunger, M.J.; McCarthy, L.E. [Flinders Univ. of South Australia, Bedford Park, SA (Australia). School of Physical Sciences; Von Niessen, W. [Flinders Univ. of South Australia, Bedford Park, SA (Australia). School of Physical Sciences

1996-09-01

The experimental (e,2e) coincidence spectroscopy, known as electron momentum spectroscopy (EMS) was applied to the trans 1,3 butadiene (C{sub 4}H{sub 6}) 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 C{sub 4}H{sub 6}. 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.

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

International Nuclear Information System (INIS)

Michalewicz, M.T.; Winkler, D.A.; Brunger, M.J.; McCarthy, L.E.; Von Niessen, W.

1996-09-01

The experimental (e,2e) coincidence spectroscopy, known as electron momentum spectroscopy (EMS) was applied to the trans 1,3 butadiene (C 4 H 6 ) 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 C 4 H 6 . 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

Structure organization and magnetic properties of microscale ferrogels: The effect of particle magnetic anisotropy

Science.gov (United States)

Ryzhkov, Aleksandr V.; Melenev, Petr V.; Balasoiu, Maria; Raikher, Yuriy L.

2016-08-01

The equilibrium structure and magnetic properties of a ferrogel object of small size (microferrogel(MFG)) are investigated by coarse-grained molecular dynamics. As a generic model of a microferrogel (MFG), a sample with a lattice-like mesh is taken. The solid phase of the MFG consists of magnetic (e.g., ferrite) nanoparticles which are mechanically linked to the mesh making some part of its nodes. Unlike previous models, the finite uniaxial magnetic anisotropy of the particles, as it is the case for real ferrogels, is taken into account. For comparison, two types of MFGs are considered: MFG-1, which dwells in virtually non-aggregated state independently of the presence of an external magnetic field, and MFG-2, which displays aggregation yet under zero field. The structure states of the samples are analyzed with the aid of angle-resolved radial distribution functions and cluster counts. The results reveal the crucial role of the matrix elasticity on the structure organization as well as on magnetization of both MFGs. The particle anisotropy, which plays insignificant role in MFG-1 (moderate interparticle magnetodipole interaction), becomes an important factor in MFG-2 (strong interaction). There, the restrictions imposed on the particle angular freedom by the elastic matrix result in notable diminution of the particle chain lengths as well as the magnetization of the sample. The approach proposed enables one to investigate a large variety of MFGs, including those of capsule type and to purposefully choose the combination of their magnetoelastic parameters.

Displacement Convexity for First-Order Mean-Field Games

KAUST Repository

Seneci, Tommaso

2018-01-01

Finally, we identify a large class of functions, that depend on solutions of MFGs, which are convex in time. Among these, we find several norms. This convexity gives bounds for the density of solutions of the planning problem.

pH and temperature dual-sensitive liposome gel based on novel cleavable mPEG-Hz-CHEMS polymeric vaginal delivery system

Science.gov (United States)

Chen, Daquan; Sun, Kaoxiang; Mu, Hongjie; Tang, Mingtan; Liang, Rongcai; Wang, Aiping; Zhou, Shasha; Sun, Haijun; Zhao, Feng; Yao, Jianwen; Liu, Wanhui

2012-01-01

Background 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. PMID:22679372

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).

ChemCam results from the Shaler outcrop in Gale crater, Mars

Science.gov (United States)

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

2015-01-01

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

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.

Chemistry of diagenetic features analyzed by ChemCam at Pahrump Hills, Gale crater, Mars

Science.gov (United States)

Nachon, Marion; Mangold, Nicolas; Forni, Olivier; Kah, Linda C.; Cousin, Agnes; Wiens, Roger C.; Anderson, Ryan; Blaney, Diana L.; Blank, Jen G.; Calef, Fred J.; Clegg, Samuel M.; Fabre, Cecile; Fisk, Martin R.; Gasnault, Olivier; Grotzinger, John P.; Kronyak, Rachel; Lanza, Nina L.; Lasue, Jeremie; Le Deit, Laetitia; Le Mouelic, Stephane; Maurice, Sylvestre; Meslin, Pierre-Yves; Oehler, D. Z.; Payre, Valerie; Rapin, William; Schroder, Susanne; Stack, Katherine M.; Sumner, Dawn

2017-01-01

The Curiosity rover's campaign at Pahrump Hills provides the first analyses of lower Mount Sharp strata. Here we report ChemCam elemental composition of a diverse assemblage of post-depositional features embedded in, or cross-cutting, the host rock. ChemCam results demonstrate their compositional diversity, especially compared to the surrounding host rock: (i) Dendritic aggregates and relief enhanced features, characterized by a magnesium enhancement and sulfur detection, and interpreted as Mg-sulfates; (ii) A localized observation that displays iron enrichment associated with sulfur, interpreted as Fe-sulfate; (iii) Dark raised ridges with varying Mg- and Ca-enriched compositions compared to host rock; (iv) Several dark-toned veins with calcium enhancement associated with fluorine detection, interpreted as fluorite veins. (v) Light-toned veins with enhanced calcium associated with sulfur detection, and interpreted as Ca-sulfates. The diversity of the Pahrump Hills diagenetic assemblage suggests a complex post-depositional history for fine-grained sediments for which the origin has been interpreted as fluvial and lacustrine. Assessment of the spatial and relative temporal distribution of these features shows that the Mg-sulfate features are predominant in the lower part of the section, suggesting local modification of the sediments by early diagenetic fluids. In contrast, light-toned Ca-sulfate veins occur in the whole section and cross-cut all other features. A relatively late stage shift in geochemical conditions could explain this observation. The Pahrump Hills diagenetic features have no equivalent compared to targets analyzed in other locations at Gale crater. Only the light-toned Ca-sulfate veins are present elsewhere, along Curiosity's path, suggesting they formed through a common late-stage process that occurred at over a broad area.

Feasibility of Integration of Selected Aspects of (CBA) Chemistry, (CHEMS) Chemistry and (PSSC) Physics into a Two Year Physical Science Sequence.

Science.gov (United States)

Fiasca, Michael Aldo

Compared, for selected outcomes, were integrated chemistry-physics courses with chemistry and physics courses taught separately. Three classes studying integrated Physical Science Study Committee (PSSC)-Chemical Bond Approach (CBA), and three classes studying integrated Physical Science Study Committee-Chemical Education Materials Study (CHEMS)…

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, Christophe; 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.

A statistical downscaling approach for roadside NO2 concentrations: Application to a WRF-Chem study for Berlin

Science.gov (United States)

Kuik, Friderike; Lauer, Axel; von Schneidemesser, Erika; Butler, Tim

2017-04-01

Many European cities continue to struggle with meeting the European air quality limits for NO2. In Berlin, Germany, most of the exceedances in NO2 recorded at monitoring sites near busy roads can be largely attributed to emissions from traffic. In order to assess the impact of changes in traffic emissions on air quality at policy relevant scales, we combine the regional atmosphere-chemistry transport model WRF-Chem at a resolution of 1kmx1km with a statistical downscaling approach. Here, we build on the recently published study evaluating the performance of a WRF-Chem setup in representing observed urban background NO2 concentrations from Kuik et al. (2016) and extend this setup by developing and testing an approach to statistically downscale simulated urban background NO2 concentrations to street level. The approach uses a multilinear regression model to relate roadside NO2 concentrations observed with the municipal monitoring network with observed NO2 concentrations at urban background sites and observed traffic counts. For this, the urban background NO2 concentrations are decomposed into a long term, a synoptic and a diurnal component using the Kolmogorov-Zurbenko filtering method. We estimate the coefficients of the regression model for five different roadside stations in Berlin representing different street types. In a next step we combine the coefficients with simulated urban background concentrations and observed traffic counts, in order to estimate roadside NO2 concentrations based on the results obtained with WRF-Chem at the five selected stations. In a third step, we extrapolate the NO2 concentrations to all major roads in Berlin. The latter is based on available data for Berlin of daily mean traffic counts, diurnal and weekly cycles of traffic as well as simulated urban background NO2 concentrations. We evaluate the NO2 concentrations estimated with this method at street level for Berlin with additional observational data from stationary measurements and

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

Energy Technology Data Exchange (ETDEWEB)

Croft, B. [Dalhousie Univ., Halifax (Canada). Dept. of Physics and Atmospheric Science; Pierce, J.R. [Dalhousie Univ., Halifax (Canada). Dept. of Physics and Atmospheric Science; Colorado State Univ., Fort Collins, CO (United States); Martin, R.V. [Dalhousie Univ., Halifax (Canada). Dept. of Physics and Atmospheric Science; Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)

2014-07-01

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 {sup 137}Cs 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 {sup 137}Cs and {sup 133}Xe 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 {sup 137}Cs global burden e-folding time is about 14 days. However, the simulated mean lifetime of aerosol-bound {sup 137}Cs 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 {sup 137}Cs 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 {sup 137}Cs injected at the Fukushima site (likely due to precipitation shortly after

Temperature-referenced high-sensitivity point-probe optical fiber chem-sensors based on cladding etched fiber Bragg gratings

OpenAIRE

Zhou, Kaiming; Chen, Xianfeng F.; Zhang, Lin; Bennion, Ian

2004-01-01

Point-probe optical fiber chem-sensors have been implemented using cladding etched fiber Bragg gratings. The sensors possess refractive index sensing capability that can be utilized to measure chemical concentrations. The Bragg wavelength shift reaches 8 nm when the index of surrounding medium changes from 1.33 to 1.44, giving maximum sensitivity more than 10 times higher than that of previously reported devices. More importantly, the dual-grating configuration of the point-probe sensors offe...

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

Tertiary-care facility's seniors association attracts its highest number of referrals through word-of-mouth. University Hospital, Denver, CO.

Science.gov (United States)

Lewicki, G

1999-01-01

University Hospital, Denver, has started its University Seniors Assn. to promote health and wellness to people 50 and older. Within four months the organization had 500 members. Now the association is 3,500 members strong.

Improvements to the WRF-Chem 3.5.1 model for quasi-hemispheric simulations of aerosols and ozone in the Arctic

Science.gov (United States)

Marelle, Louis; Raut, Jean-Christophe; Law, Kathy S.; Berg, Larry K.; Fast, Jerome D.; Easter, Richard C.; Shrivastava, Manish; Thomas, Jennie L.

2017-10-01

In this study, the WRF-Chem regional model is updated to improve simulated short-lived pollutants (e.g., aerosols, ozone) in the Arctic. Specifically, we include in WRF-Chem 3.5.1 (with SAPRC-99 gas-phase chemistry and MOSAIC aerosols) (1) a correction to the sedimentation of aerosols, (2) dimethyl sulfide (DMS) oceanic emissions and gas-phase chemistry, (3) an improved representation of the dry deposition of trace gases over seasonal snow, and (4) an UV-albedo dependence on snow and ice cover for photolysis calculations. We also (5) correct the representation of surface temperatures over melting ice in the Noah Land Surface Model and (6) couple and further test the recent KF-CuP (Kain-Fritsch + Cumulus Potential) cumulus parameterization that includes the effect of cumulus clouds on aerosols and trace gases. The updated model is used to perform quasi-hemispheric simulations of aerosols and ozone, which are evaluated against surface measurements of black carbon (BC), sulfate, and ozone as well as airborne measurements of BC in the Arctic. The updated model shows significant improvements in terms of seasonal aerosol cycles at the surface and root mean square errors (RMSEs) for surface ozone, aerosols, and BC aloft, compared to the base version of the model and to previous large-scale evaluations of WRF-Chem in the Arctic. These improvements are mostly due to the inclusion of cumulus effects on aerosols and trace gases in KF-CuP (improved RMSE for surface BC and BC profiles, surface sulfate, and surface ozone), the improved surface temperatures over sea ice (surface ozone, BC, and sulfate), and the updated trace gas deposition and UV albedo over snow and ice (improved RMSE and correlation for surface ozone). DMS emissions and chemistry improve surface sulfate at all Arctic sites except Zeppelin, and correcting aerosol sedimentation has little influence on aerosols except in the upper troposphere.

Multiple Family Groups for Child Behavior Difficulties: Retention Among Child Welfare-Involved Caregivers

Science.gov (United States)

Gopalan, Geetha; Fuss, Ashley; Wisdom, Jennifer P.

2015-01-01

Purpose: The Multiple Family Group (MFG) service delivery model to reduce childhood disruptive behavior disorders has shown promise in engaging child welfare-involved families. This qualitative study examines caregivers' perceptions of factors that influence retention in MFGs among child welfare-involved families. Methods: Twenty-five…

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.

The ChemScreen project to design a pragmatic alternative approach to predict reproductive toxicity of chemicals

DEFF Research Database (Denmark)

van der Burg, Bart; Wedebye, Eva Bay; Dietrich, Daniel R.

2015-01-01

to validate the test panel using mechanistic approaches. We are actively engaged in promoting regulatory acceptance of the tools developed as an essential step towards practical application, including case studies for read-across purposes. With this approach, a significant saving in animal use and associated......There is a great need for rapid testing strategies for reproductive toxicity testing, avoiding animal use. The EU Framework program 7 project ChemScreen aimed to fill this gap in a pragmatic manner preferably using validated existing tools and place them in an innovative alternative testing...

ChemCam Passive Sky Spectroscopy at Gale Crater, Mars: Interannual Variability in Dust Aerosol Particle Size, Missing Water Vapor, and the Molecular Oxygen Problem

Science.gov (United States)

McConnochie, T. H.; Smith, M. D.; Wolff, M. J.; Bender, S. C.; Lemmon, M. T.; Wiens, R. C.; Maurice, S.; Gasnault, O.; Lasue, J.; Meslin, P. Y.; Harri, A. M.; Genzer, M.; Kemppinen, O.; Martinez, G.; DeFlores, L. P.; Blaney, D. L.; Johnson, J. R.; Bell, J. F., III; Trainer, M. G.; Lefèvre, F.; Atreya, S. K.; Mahaffy, P. R.; Wong, M. H.; Franz, H. B.; Guzewich, S.; Villanueva, G. L.; Khayat, A. S.

2017-12-01

The Mars Science Laboratory's (MSL) ChemCam spectrometer measures atmospheric aerosol properties and gas abundances by operating in passive mode and observing scattered sky light at two different elevation angles. We have previously [e. g. 1, 2] presented the methodology and results of these ChemCam Passive Sky observations. Here we will focus on three of the more surprising results that we have obtained: (1) depletion of the column water vapor at Gale Crater relative to that of the surrounding region combined with a strong enhancement of the local column water vapor relative to pre-dawn in-situ measurements, (2) an interannual change in the effective particle size of dust aerosol during the aphelion season, and (3) apparent seasonal and interannual variability in molecular oxygen that differs significantly from the expected behavior of a non-condensable trace gas and differs significantly from global climate model expectations. The ChemCam passive sky water vapor measurements are quite robust but their interpretation depends on the details of measurements as well as on the types of water vapor vertical distributions that can be produced by climate models. We have a high degree of confidence in the dust particle size changes but since aerosol results in general are subject to a variety of potential systematic effects our particle size results would benefit from confirmation by other techniques [c.f. 3]. For the ChemCam passive sky molecular oxygen results we are still working to constrain the uncertainties well enough to confirm the observed surprising behavior, motivated by similarly surprising atmospheric molecular oxygen variability observed by MSL's Sample Analysis at Mars (SAM) instrument [4]. REFERENCES: [1] McConnochie, et al. (2017), Icarus (submitted). [2] McConnochie, et al. (2017), abstract # 3201, The 6th International Workshop on the Mars Atmosphere: Granada, Spain. [3] Vicente-Retortillo et al. (2017), GRL, 44. [4] Trainer et al. (2017), 2017 AGU Fall

77 FR 28447 - Electronic On-Board Recorders for Hours-of-Service Compliance; Removal of Final Rule Vacated by...

Science.gov (United States)

2012-05-14

... rule. Owner-Operator Indep. Drivers Ass'n v. Federal Motor Carrier Safety Admin., 656 F.3d 580 (7th Cir... determination is available for inspection or copying in the Regulations.gov Web site listed under ADDRESSES...

Regulation of gene expression in human mammary epithelium: effect of breast pumping

Science.gov (United States)

Little is known of the molecular regulation of human milk production because of limitations in obtaining mammary tissue from lactating women. Our objectives were to evaluate whether RNA isolated from breast milk fat globules (MFGs) could be an alternative to mammary biopsies and to determine whether...

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…

Dust modeling over East Asia during the summer of 2010 using the WRF-Chem model

Science.gov (United States)

Zhang, B.; Huang, J.; Chen, S.

2017-12-01

An intense summer dust storm over East Asia during June 24-27, 2010, was systematically analyzed using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) and a variety of in situ measurements and satellite retrievals. The results showed that the WRF-Chem model captured the spatial and temporal distributions of meteorological factors and dust aerosols over East Asia. This summer dust storm was initiated by the approach of a transverse trough in the northwestern Xinjiang. Because of the passage of the cutoff-low, a large amount of cold air was transported southward and further enhanced in the narrow valleys of the Altai and Tianshan Mountains, which resulted in higher wind speeds and huge dust emissions over the Taklimakan Desert (TD). Dust emission fluxes over the TD were as high as 54 μg m-2 s-1 on June 25th. The dust aerosols from the TD then swept across Inner Mongolia, Ningxia and Mongolia, and some were also transported eastward to Beijing, Tianjin, the Hebei region, and even South Korea and Japan. The simulations further showed that summer dust over East Asia exerts an important influence on the radiation budget in the Earth-atmosphere system. Dust heat the atmosphere at a maximum heating rate of 0.14 k day-1, effectively changing the vertical stability of the atmosphere and affecting climate change at regional and even global scales. The dust event-averaged direct radiative forcing induced by dust particles over the TD at all-sky was -6.0, -16.8 and 10.8 W m-2 at the top of the atmosphere, the surface, and in the atmosphere, respectively.

29 CFR 784.114 - Application of exemptions on a workweek basis.

Science.gov (United States)

2010-07-01

... Provisions Relating to Fishing and Aquatic Products Principles Applicable to the Two Exemptions § 784.114...; Puerto Rico Tobacco Marketing Co-op. Ass'n. v. McComb, 181 F. 2d 697). Thus, the workweek is the unit of...

DayCent-Chem Simulations of Ecological and Biogeochemical Processes of Eight Mountain Ecosystems in the United States

Science.gov (United States)

Hartman, Melannie D.; Baron, Jill S.; Clow, David W.; Creed, Irena F.; Driscoll, Charles T.; Ewing, Holly A.; Haines, Bruce D.; Knoepp, Jennifer; Lajtha, Kate; Ojima, Dennis S.; Parton, William J.; Renfro, Jim; Robinson, R. Bruce; Van Miegroet, Helga; Weathers, Kathleen C.; Williams, Mark W.

2009-01-01

Atmospheric deposition of nitrogen (N) and sulfur (S) cause complex responses in ecosystems, from fertilization to forest ecosystem decline, freshwater eutrophication to acidification, loss of soil base cations, and alterations of disturbance regimes. DayCent-Chem, an ecosystem simulation model that combines ecosystem nutrient cycling and plant dynamics with aqueous geochemical equilibrium calculations, was developed to address ecosystem responses to combined atmospheric N and S deposition. It is unique among geochemically-based models in its dynamic biological cycling of N and its daily timestep for investigating ecosystem and surface water chemical response to episodic events. The model was applied to eight mountainous watersheds in the United States. The sites represent a gradient of N deposition across locales, from relatively pristine to N-saturated, and a variety of ecosystem types and climates. Overall, the model performed best in predicting stream chemistry for snowmelt-dominated sites. It was more difficult to predict daily stream chemistry for watersheds with deep soils, high amounts of atmospheric deposition, and a large degree of spatial heterogeneity. DayCent-Chem did well in representing plant and soil carbon and nitrogen pools and fluxes. Modeled stream nitrate (NO3-) and ammonium (NH4+) concentrations compared well with measurements at all sites, with few exceptions. Simulated daily stream sulfate (SO42-) concentrations compared well to measured values for sites where SO42- deposition has been low and where SO42- adsorption/desorption reactions did not seem to be important. The concentrations of base cations and silica in streams are highly dependent on the geochemistry and weathering rates of minerals in each catchment, yet these were rarely, if ever, known. Thus, DayCent-Chem could not accurately predict weathering products for some catchments. Additionally, few data were available for exchangeable soil cations or the magnitude of base cation

Amiata donkeys: fat globule characteristics, milk gross composition and fatty acids

Directory of Open Access Journals (Sweden)

Mina Martini

2014-02-01

Full Text Available Amiata donkeys are a native breed reared in central Italy. Safeguarding native donkey breeds represents an opportunity for the development of marginal areas, especially given that donkey milk is now appearing on the market due to its potential benefits for human health. To date, only a few studies have focused on the characteristics of the milk fat globules (MFGs in the donkey species. The aim of this study was to assess the morphometric characteristics of the fat globules, gross composition and fatty acid classes in milk from Amiata donkeys reared according to the typical farming and feeding systems of the area of origin. Individual milk samples, collected from 28 Amiata donkeys between 90 and 150 days of lactation, showed the following average composition (g/100 mL: 9.47 dry matter, 1.63 protein, 0.78 casein, 0.53 fat, 7.12 lactose, and 0.36 ash. The unsaturated:saturated fatty acids ratio in milk was close to 1. The percentage of short chains was 12.29, and the percentage of long chain fatty acids was 47.64. The donkey MFGs showed an average diameter of 1.92 μm, and a number of 2.18*109/mL. Regarding MFG distribution, 70% of the globules donkey of milk are smaller than 2 μm. In conclusion, the gross composition and fatty acids of Amiata donkey milk showed similarities with milk from other Italian donkey breeds, with the exception of the monounsaturated fatty acid values which were slightly higher. Donkey MFGs had a smaller diameter and were fewer than in the ruminant species.

Improvements to the WRF-Chem 3.5.1 model for quasi-hemispheric simulations of aerosols and ozone in the Arctic

Directory of Open Access Journals (Sweden)

L. Marelle

2017-10-01

Full Text Available In this study, the WRF-Chem regional model is updated to improve simulated short-lived pollutants (e.g., aerosols, ozone in the Arctic. Specifically, we include in WRF-Chem 3.5.1 (with SAPRC-99 gas-phase chemistry and MOSAIC aerosols (1 a correction to the sedimentation of aerosols, (2 dimethyl sulfide (DMS oceanic emissions and gas-phase chemistry, (3 an improved representation of the dry deposition of trace gases over seasonal snow, and (4 an UV-albedo dependence on snow and ice cover for photolysis calculations. We also (5 correct the representation of surface temperatures over melting ice in the Noah Land Surface Model and (6 couple and further test the recent KF-CuP (Kain–Fritsch + Cumulus Potential cumulus parameterization that includes the effect of cumulus clouds on aerosols and trace gases. The updated model is used to perform quasi-hemispheric simulations of aerosols and ozone, which are evaluated against surface measurements of black carbon (BC, sulfate, and ozone as well as airborne measurements of BC in the Arctic. The updated model shows significant improvements in terms of seasonal aerosol cycles at the surface and root mean square errors (RMSEs for surface ozone, aerosols, and BC aloft, compared to the base version of the model and to previous large-scale evaluations of WRF-Chem in the Arctic. These improvements are mostly due to the inclusion of cumulus effects on aerosols and trace gases in KF-CuP (improved RMSE for surface BC and BC profiles, surface sulfate, and surface ozone, the improved surface temperatures over sea ice (surface ozone, BC, and sulfate, and the updated trace gas deposition and UV albedo over snow and ice (improved RMSE and correlation for surface ozone. DMS emissions and chemistry improve surface sulfate at all Arctic sites except Zeppelin, and correcting aerosol sedimentation has little influence on aerosols except in the upper troposphere.

Errors and improvements in the use of archived meteorological data for chemical transport modeling: an analysis using GEOS-Chem v11-01 driven by GEOS-5 meteorology

Directory of Open Access Journals (Sweden)

K. Yu

2018-01-01

Full Text Available Global simulations of atmospheric chemistry are commonly conducted with off-line chemical transport models (CTMs driven by archived meteorological data from general circulation models (GCMs. The off-line approach has the advantages of simplicity and expediency, but it incurs errors due to temporal averaging in the meteorological archive and the inability to reproduce the GCM transport algorithms exactly. The CTM simulation is also often conducted at coarser grid resolution than the parent GCM. Here we investigate this cascade of CTM errors by using 222Rn–210Pb–7Be chemical tracer simulations off-line in the GEOS-Chem CTM at rectilinear 0.25°  ×  0.3125° (≈ 25 km and 2°  ×  2.5° (≈ 200 km resolutions and online in the parent GEOS-5 GCM at cubed-sphere c360 (≈ 25 km and c48 (≈ 200 km horizontal resolutions. The c360 GEOS-5 GCM meteorological archive, updated every 3 h and remapped to 0.25°  ×  0.3125°, is the standard operational product generated by the NASA Global Modeling and Assimilation Office (GMAO and used as input by GEOS-Chem. We find that the GEOS-Chem 222Rn simulation at native 0.25°  ×  0.3125° resolution is affected by vertical transport errors of up to 20 % relative to the GEOS-5 c360 online simulation, in part due to loss of transient organized vertical motions in the GCM (resolved convection that are temporally averaged out in the 3 h meteorological archive. There is also significant error caused by operational remapping of the meteorological archive from a cubed-sphere to a rectilinear grid. Decreasing the GEOS-Chem resolution from 0.25°  ×  0.3125° to 2°  ×  2.5° induces further weakening of vertical transport as transient vertical motions are averaged out spatially and temporally. The resulting 222Rn concentrations simulated by the coarse-resolution GEOS-Chem are overestimated by up to 40 % in surface air relative to the

Air pollution modeling over very complex terrain: An evaluation of WRF-Chem over Switzerland for two 1-year periods

Science.gov (United States)

Ritter, Mathias; Müller, Mathias D.; Tsai, Ming-Yi; Parlow, Eberhard

2013-10-01

The fully coupled chemistry module (WRF-Chem) within the Weather Research and Forecasting (WRF) model has been implemented over a Swiss domain for the years 2002 and 1991. The very complex terrain requires a high horizontal resolution (2 × 2 km2), which is achieved by nesting the Swiss domain into a coarser European one. The temporal and spatial distribution of O3, NO2 and PM10 as well as temperature and solar radiation are evaluated against ground-based measurements. The model performs well for the meteorological parameters with Pearson correlation coefficients of 0.92 for temperature and 0.88-0.89 for solar radiation. Temperature has root mean square errors (RMSE) of 3.30 K and 3.51 K for 2002 and 1991 and solar radiation has RMSEs of 122.92 and 116.35 for 2002 and 1991, respectively. For the modeled air pollutants, a multi-linear regression post-processing was used to eliminate systematic bias. Seasonal variations of post-processed air pollutants are represented correctly. However, short-term peaks of several days are not captured by the model. Averaged daily maximum and daily values of O3 achieved Pearson correlation coefficients of 0.69-0.77 whereas averaged NO2 and PM10 had the highest correlations for yearly average values (0.68-0.78). The spatial distribution reveals the importance of PM10 advection from the Po valley to southern Switzerland (Ticino). The absolute errors are ranging from - 10 to 15 μg/m3 for ozone, - 9 to 3 μg/m3 for NO2 and - 4 to 3 μg/m3 for PM10. However, larger errors occur along heavily trafficked roads, in street canyons or on mountains. We also compare yearly modeled results against a dedicated Swiss dispersion model for NO2 and PM10. The dedicated dispersion model has a slightly better statistical performance, but WRF-Chem is capable of computing the temporal evolution of three-dimensional data for a variety of air pollutants and meteorological parameters. Overall, WRF-Chem with the application of post-processing algorithms can

The AtChem On-line model and Electronic Laboratory Notebook (ELN): A free community modelling tool with provenance capture

Science.gov (United States)

Young, J. C.; Boronska, K.; Martin, C. J.; Rickard, A. R.; Vázquez Moreno, M.; Pilling, M. J.; Haji, M. H.; Dew, P. M.; Lau, L. M.; Jimack, P. K.

2010-12-01

AtChem On-line1 is a simple to use zero-dimensional box modelling toolkit, developed for use by laboratory, field and chamber scientists. Any set of chemical reactions can be simulated, in particular the whole Master Chemical Mechanism (MCM2) or any subset of it. Parameters and initial data can be provided through a self-explanatory web form and the resulting model is compiled and run on a dedicated server. The core part of the toolkit, providing a robust solver for thousands of chemical reactions, is written in Fortran and uses SUNDIALS3 CVODE libraries. Chemical systems can be constrained at multiple, user-determined timescales; this enabled studies of radical chemistry at one minute timescales. AtChem On-line is free to use and requires no installation - a web browser, text editor and any compressing software is all the user needs. CPU and storage are provided by the server (input and output data are saved indefinitely). An off-line version is also being developed, which will provide batch processing, an advanced graphical user interface and post-processing tools, for example, Rate of Production Analysis (ROPA) and chainlength analysis. The source code is freely available for advanced users wishing to adapt and run the program locally. Data management, dissemination and archiving are essential in all areas of science. In order to do this in an efficient and transparent way, there is a critical need to capture high quality metadata/provenance for modelling activities. An Electronic Laboratory Notebook (ELN) has been developed in parallel with AtChem Online as part of the EC EUROCHAMP24 project. In order to use controlled chamber experiments to evaluate the MCM, we need to be able to archive, track and search information on all associated chamber model runs, so that they can be used in subsequent mechanism development. Therefore it would be extremely useful if experiment and model metadata/provenance could be easily and automatically stored electronically

Weakly coupled mean-field game systems

KAUST Repository

Gomes, Diogo A.

2016-07-14

Here, we prove the existence of solutions to first-order mean-field games (MFGs) arising in optimal switching. First, we use the penalization method to construct approximate solutions. Then, we prove uniform estimates for the penalized problem. Finally, by a limiting procedure, we obtain solutions to the MFG problem. © 2016 Elsevier Ltd

Conservation laws arising in the study of forward-forward Mean-Field Games

KAUST Repository

Gomes, Diogo A.; Nurbekyan, Levon; Sedjro, Marc

2017-01-01

We consider forward-forward Mean Field Game (MFG) models that arise in numerical approximations of stationary MFGs. First, we establish a link between these models and a class of hyperbolic conservation laws as well as certain nonlinear wave equations. Second, we investigate existence and long-time behavior of solutions for such models.

Conservation laws arising in the study of forward-forward Mean-Field Games

KAUST Repository

Gomes, Diogo A.

2017-04-24

We consider forward-forward Mean Field Game (MFG) models that arise in numerical approximations of stationary MFGs. First, we establish a link between these models and a class of hyperbolic conservation laws as well as certain nonlinear wave equations. Second, we investigate existence and long-time behavior of solutions for such models.

Image Quality in High-resolution and High-cadence Solar Imaging

Science.gov (United States)

Denker, C.; Dineva, E.; Balthasar, H.; Verma, M.; Kuckein, C.; Diercke, A.; González Manrique, S. J.

2018-03-01

Broad-band imaging and even imaging with a moderate bandpass (about 1 nm) provides a photon-rich environment, where frame selection (lucky imaging) becomes a helpful tool in image restoration, allowing us to perform a cost-benefit analysis on how to design observing sequences for imaging with high spatial resolution in combination with real-time correction provided by an adaptive optics (AO) system. This study presents high-cadence (160 Hz) G-band and blue continuum image sequences obtained with the High-resolution Fast Imager (HiFI) at the 1.5-meter GREGOR solar telescope, where the speckle-masking technique is used to restore images with nearly diffraction-limited resolution. The HiFI employs two synchronized large-format and high-cadence sCMOS detectors. The median filter gradient similarity (MFGS) image-quality metric is applied, among others, to AO-corrected image sequences of a pore and a small sunspot observed on 2017 June 4 and 5. A small region of interest, which was selected for fast-imaging performance, covered these contrast-rich features and their neighborhood, which were part of Active Region NOAA 12661. Modifications of the MFGS algorithm uncover the field- and structure-dependency of this image-quality metric. However, MFGS still remains a good choice for determining image quality without a priori knowledge, which is an important characteristic when classifying the huge number of high-resolution images contained in data archives. In addition, this investigation demonstrates that a fast cadence and millisecond exposure times are still insufficient to reach the coherence time of daytime seeing. Nonetheless, the analysis shows that data acquisition rates exceeding 50 Hz are required to capture a substantial fraction of the best seeing moments, significantly boosting the performance of post-facto image restoration.

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Multifocus microscopy with precise color multi-phase diffractive optics applied in functional neuronal imaging.

Science.gov (United States)

Abrahamsson, Sara; Ilic, Rob; Wisniewski, Jan; Mehl, Brian; Yu, Liya; Chen, Lei; Davanco, Marcelo; Oudjedi, Laura; Fiche, Jean-Bernard; Hajj, Bassam; Jin, Xin; Pulupa, Joan; Cho, Christine; Mir, Mustafa; El Beheiry, Mohamed; Darzacq, Xavier; Nollmann, Marcelo; Dahan, Maxime; Wu, Carl; Lionnet, Timothée; Liddle, J Alexander; Bargmann, Cornelia I

2016-03-01

Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cells nuclei to entire embryos. We here describe pattern designs and nanofabrication methods for diffractive optics that optimize the light-efficiency of the central optical component of MFM: the diffractive multifocus grating (MFG). We also implement a "precise color" MFM layout with MFGs tailored to individual fluorophores in separate optical arms. The reported advancements enable faster and brighter volumetric time-lapse imaging of biological samples. In live microscopy applications, photon budget is a critical parameter and light-efficiency must be optimized to obtain the fastest possible frame rate while minimizing photodamage. We provide comprehensive descriptions and code for designing diffractive optical devices, and a detailed methods description for nanofabrication of devices. Theoretical efficiencies of reported designs is ≈90% and we have obtained efficiencies of > 80% in MFGs of our own manufacture. We demonstrate the performance of a multi-phase MFG in 3D functional neuronal imaging in living C. elegans.

Towards a Comprehensive Dynamic-chemistry Assimilation for Eos-Chem: Plans and Status in NASA's Data Assimilation Office

Science.gov (United States)

Pawson, Steven; Lin, Shian-Jiann; Rood, Richard B.; Stajner, Ivanka; Nebuda, Sharon; Nielsen, J. Eric; Douglass, Anne R.

2000-01-01

In order to support the EOS-Chem project, a comprehensive assimilation package for the coupled chemical-dynamical system is being developed by the Data Assimilation Office at NASA GSFC. This involves development of a coupled chemistry/meteorology model and of data assimilation techniques for trace species and meteorology. The model is being developed using the flux-form semi-Lagrangian dynamical core of Lin and Rood, the physical parameterizations from the NCAR Community Climate Model, and atmospheric chemistry modules from the Atmospheric Chemistry and Dynamics branch at NASA GSFC. To date the following results have been obtained: (i) multi-annual simulations with the dynamics-radiation model show the credibility of the package for atmospheric simulations; (ii) initial simulations including a limited number of middle atmospheric trace gases reveal the realistic nature of transport mechanisms, although there is still a need for some improvements. Samples of these results will be shown. A meteorological assimilation system is currently being constructed using the model; this will form the basis for the proposed meteorological/chemical assimilation package. The latter part of the presentation will focus on areas targeted for development in the near and far terms, with the objective of Providing a comprehensive assimilation package for the EOS-Chem science experiment. The first stage will target ozone assimilation. The plans also encompass a reanalysis (ReSTS) for the 1991-1995 period, which includes the Mt. Pinatubo eruption and the time when a large number of UARS observations were available. One of the most challenging aspects of future developments will be to couple theoretical advances in tracer assimilation with the practical considerations of a real environment and eventually a near-real-time assimilation system.

Is ozone model bias driven by errors in cloud predictions? A quantitative assessment using satellite cloud retrievals in WRF-Chem

Science.gov (United States)

Ryu, Y. H.; Hodzic, A.; Barré, J.; Descombes, G.; Minnis, P.

2017-12-01

Clouds play a key role in radiation and hence O3 photochemistry by modulating photolysis rates and light-dependent emissions of biogenic volatile organic compounds (BVOCs). It is not well known, however, how much of the bias in O3 predictions is caused by inaccurate cloud predictions. This study quantifies the errors in surface O3 predictions associated with clouds in summertime over CONUS using the Weather Research and Forecasting with Chemistry (WRF-Chem) model. Cloud fields used for photochemistry are corrected based on satellite cloud retrievals in sensitivity simulations. It is found that the WRF-Chem model is able to detect about 60% of clouds in the right locations and generally underpredicts cloud optical depths. The errors in hourly O3 due to the errors in cloud predictions can be up to 60 ppb. On average in summertime over CONUS, the errors in 8-h average O3 of 1-6 ppb are found to be attributable to those in cloud predictions under cloudy sky conditions. The contribution of changes in photolysis rates due to clouds is found to be larger ( 80 % on average) than that of light-dependent BVOC emissions. The effects of cloud corrections on O­3 are about 2 times larger in VOC-limited than NOx-limited regimes, suggesting that the benefits of accurate cloud predictions would be greater in VOC-limited than NOx-limited regimes.

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

Constraints on Eurasian ship NOx emissions using OMI NO2 observations and GEOS-Chem

Science.gov (United States)

Vinken, Geert C. M.; Boersma, Folkert; van Donkelaar, Aaron; Zhang, Lin

2013-04-01

Ships emit large quantities of nitrogen oxides (NOx = NO + NO2), important precursors for ozone (O3) and particulate matter formation. Ships burn low-grade marine heavy fuel due to the limited regulations that exist for the maritime sector in international waters. Previous studies showed that global ship NOx emission inventories amount to 3.0-10.4 Tg N per year (15-30% of total NOx emissions), with most emissions close to land and affecting air quality in densely populated coastal regions. Bottom-up inventories depend on the extrapolation of a relatively small number of measurements that are often unable to capture annual emission changes and can suffer from large uncertainties. Satellites provide long-term, high-resolution retrievals that can be used to improve emission estimates. In this study we provide top-down constraints on ship NOx emissions in major European ship routes, using observed NO2 columns from the Ozone Monitoring Instrument (OMI) and NO2 columns simulated with the nested (0.5°×0.67°) version of the GEOS-Chem chemistry transport model. We use a plume-in-grid treatment of ship NOx emissions to account for in-plume chemistry in our model. We ensure consistency between the retrievals and model simulations by using the high-resolution GEOS-Chem NO2 profiles as a priori. We find evidence that ship emissions in the Mediterranean Sea are geographically misplaced by up to 150 km and biased high by a factor of 4 as compared to the most recent (EMEP) ship emission inventory. Better agreement is found over the shipping lane between Spain and the English Channel. We extend our approach and also provide constraints for major ship routes in the Red Sea and Indian Ocean. Using the full benefit of the long-term retrieval record of OMI, we present a new Eurasian ship emission inventory for the years 2005 to 2010, based on the EMEP and AMVER-ICOADS inventories, and top-down constraints from the satellite retrievals. Our work shows that satellite retrievals can

El Sensor Químico (ChemSensor) como herramienta complementaria en el análisis sensorial de vinos

OpenAIRE

Pérez Mateos, Miriam; Giménez Cobo, Lucia; Carrasco Manzano, Juan Atanasio

2012-01-01

El Sensor Químico (ChemSensor) o pseudo-nariz electrónica determina la agrupación de alimentos por similitudes y según la distancias entre grupos, a partir del análisis de espectrometría de masas de los compuestos volátiles y/o los ácidos grasos. Se trata de una herramienta excelente como complemento al análisis sensorial. Es muy útil en la clasificación y predicción de productos alimenticios según su origen, procesado y conservación; en la optimización de procesos y en aplicaciones de contro...

Geology of a Stable Intraplate Region: The Cape Verde/Canary Basin,

Science.gov (United States)

1982-03-01

other limited area. The National Geophysical and areas, sounding tracks are sufficiently Solar -Terrestrial Data Center (NGSDC) dense to permit...Scientists. New York. McGraw-Hill, 471 p. Ball. M.M. (1969). Discussion Diapers of Magdalena Delta. Bull. Am. Assn. Petrol. Burke, K. and J.T. Wilson (1972

A Quantitative Assessment of the Research Chefs Association Core Competencies for the Practicing Culinologist

Science.gov (United States)

Bissett, Rachel L.; Cheng, Michael S. H.; Brannan, Robert G.

2010-01-01

Professional organizations have linked core competency to professional success and competitive strategy. The Research Chefs Assn. (RCA) recently released 43 core competencies for practicing culinologists. Culinology[R] is a profession that links skills of culinary arts and food science and technology in the development of food products. An online…

77 FR 8449 - Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Nine Bexar...

Science.gov (United States)

2012-02-14

... Center for Biological Diversity, Citizens Alliance for Smart Expansion, and Aquifer Guardians in Urban... climate change, pollution, invasive species, and stochastic events. Our Response: While we agree that...'t of Interior, 344 F.Supp.2d 108, 124 (D.D.C. 2004) (``Cape Hatteras''); Home Builders Ass'n of...

Design and Development of ChemInfoCloud: An Integrated Cloud Enabled Platform for Virtual Screening.

Science.gov (United States)

Karthikeyan, Muthukumarasamy; Pandit, Deepak; Bhavasar, Arvind; Vyas, Renu

2015-01-01

The power of cloud computing and distributed computing has been harnessed to handle vast and heterogeneous data required to be processed in any virtual screening protocol. A cloud computing platorm ChemInfoCloud was built and integrated with several chemoinformatics and bioinformatics tools. The robust engine performs the core chemoinformatics tasks of lead generation, lead optimisation and property prediction in a fast and efficient manner. It has also been provided with some of the bioinformatics functionalities including sequence alignment, active site pose prediction and protein ligand docking. Text mining, NMR chemical shift (1H, 13C) prediction and reaction fingerprint generation modules for efficient lead discovery are also implemented in this platform. We have developed an integrated problem solving cloud environment for virtual screening studies that also provides workflow management, better usability and interaction with end users using container based virtualization, OpenVz.

78 FR 79729 - Integrated Mortgage Disclosures Under the Real Estate Settlement Procedures Act (Regulation X...

Science.gov (United States)

2013-12-31

... Statistics from 2003 through 2013). \\32\\ Press Release, Mortg. Bankers Ass'n, Short-term Delinquencies Fall to Pre-Recession Levels, Loans in Foreclosure Tie All-Time Record in Latest MBA National Delinquency.../GDPC1 . \\31\\ Bureau of Labor Statistics, U.S. Dep't of Labor, Labor Force Statistics from the Current...

Operational on-line coupled chemical weather forecasts for Europe with WRF/Chem

Science.gov (United States)

Hirtl, Marcus; Mantovani, Simone; Krüger, Bernd C.; Flandorfer, Claudia; Langer, Matthias

2014-05-01

Air quality is a key element for the well-being and quality of life of European citizens. Air pollution measurements and modeling tools are essential for the assessment of air quality according to EU legislation. The responsibilities of ZAMG as the national weather service of Austria include the support of the federal states and the public in questions connected to the protection of the environment in the frame of advisory and counseling services as well as expert opinions. ZAMG conducts daily Air-Quality forecasts using the on-line coupled model WRF/Chem. Meteorology is simulated simultaneously with the emissions, turbulent mixing, transport, transformation, and fate of trace gases and aerosols. The emphasis of the application is on predicting pollutants over Austria. Two domains are used for the simulations: the mother domain covers Europe with a resolution of 12 km, the inner domain includes the alpine region with a horizontal resolution of 4 km; 45 model levels are used in the vertical direction. The model runs 2 times per day for a period of 72 hours and is initialized with ECMWF forecasts. On-line coupled models allow considering two-way interactions between different atmospheric processes including chemistry (both gases and aerosols), clouds, radiation, boundary layer, emissions, meteorology and climate. In the operational set-up direct-, indirect and semi-direct effects between meteorology and air chemistry are enabled. The model is running on the HPCF (High Performance Computing Facility) of the ZAMG. In the current set-up 1248 CPUs are used. As the simulations need a big amount of computing resources, a method to safe I/O-time was implemented. Every MPI task writes all its output into the shared memory filesystem of the compute nodes. Once the WRF/Chem integration is finished, all split NetCDF-files are merged and saved on the global file system. The merge-routine is based on parallel-NetCDF. With this method the model runs about 30% faster on the SGI

Photochemical Pollution Modeling of Ozone at Metropolitan Area of Porto Alegre - RS/Brazil using WRF/Chem

Science.gov (United States)

Cuchiara, G. C.; Carvalho, J.

2013-05-01

One of the main problems related to air pollution in urban areas is caused by photochemical oxidants, particularly troposphere ozone (O3), which is considered a harmful substance. The O3 precursors (carbon monoxide CO, nitrogen oxides NOx and hydrocarbons HCs) are predominantly of anthropogenic origin in these areas, and vehicles are the main emission sources. Due to the increased urbanization and industrial development in recent decades, air pollutant emissions have increased likewise, mainly by mobile sources in the highly urbanized and developed areas, such as the Metropolitan Area of Porto Alegre-RS (MAPA). According to legal regulations implemented in Brazil in 2005, which aimed at increasing the fraction of biofuels in the national energy matrix, 2% biodiesel were supposed to be added to the fuel mixture within three years, and up to 5% after eight years of implementation of these regulations. Our work performs an analysis of surface concentrations for O3, NOx, CO, and HCs through numerical simulations with WRF/Chem (Weather Research and Forecasting model with Chemistry). The model is validated against observational data obtained from the local urban air quality network for the period from January 5 to 9, 2009 (96 hours). One part of the study focused on the comparison of simulated meteorological variables, to observational data from two stations in MAPA. The results showed that the model simulates well the diurnal evolution of pressure and temperature at the surface, but is much less accurate for wind speed. Another part included the evaluation of model results of WRF/Chem for O3 versus observed data at air quality stations Esteio and Porto Alegre. Comparisons between simulated and observed O3 revealed that the model simulates well the evolution of the observed values, but on many occasions the model did not reproduce well the maximum and minimum concentrations. Finally, a preliminary quantitative sensitivity study on the impact of biofuel on the

Potentially Inappropriate Medication Use Among Elderly Home Care Patients in Europe

Czech Academy of Sciences Publication Activity Database

Fialová, D.; Topinková, E.; Gambassi, G.; Finne-Soveri, H.; Jónsson, P.; Carpenter, I.; Schroll, M.; Onder, G.; Sorbye, L.W.; Wagner, C.; Reissigová, Jindra; Bernabei, R.

2005-01-01

Roč. 293, č. 11 (2005), s. 1348-1358 ISSN 0098-7484 Institutional research plan: CEZ:AV0Z10300504 Keywords : potentially inappropriate medication * prevalence * independent correlates Subject RIV: FQ - Public Health Care , Social Medicine Impact factor: 23.332, year: 2005 http://jama.ama-assn.org/cgi/content/abstract/293/11/1348

76 FR 14856 - Video Description: Implementation of the Twenty-First Century Communications and Video...

Science.gov (United States)

2011-03-18

... ECFS ( http://www.fcc.gov/cgb/ecfs/ ). Documents will be available electronically in ASCII, Word 97... afford better access to television programs for individuals who are blind or visually impaired, enabling...\\ Motion Picture Ass'n of America, Inc. v. Federal Communications Comm., 309 F.3d 796 (D.C. Cir. 2002). \\5...

Advances in molecular quantum chemistry contained in the Q-Chem 4 program package

Science.gov (United States)

Shao, Yihan; Gan, Zhengting; Epifanovsky, Evgeny; Gilbert, Andrew T. B.; Wormit, Michael; Kussmann, Joerg; Lange, Adrian W.; Behn, Andrew; Deng, Jia; Feng, Xintian; Ghosh, Debashree; Goldey, Matthew; Horn, Paul R.; Jacobson, Leif D.; Kaliman, Ilya; Khaliullin, Rustam Z.; Kuś, Tomasz; Landau, Arie; Liu, Jie; Proynov, Emil I.; Rhee, Young Min; Richard, Ryan M.; Rohrdanz, Mary A.; Steele, Ryan P.; Sundstrom, Eric J.; Woodcock, H. Lee, III; Zimmerman, Paul M.; Zuev, Dmitry; Albrecht, Ben; Alguire, Ethan; Austin, Brian; Beran, Gregory J. O.; Bernard, Yves A.; Berquist, Eric; Brandhorst, Kai; Bravaya, Ksenia B.; Brown, Shawn T.; Casanova, David; Chang, Chun-Min; Chen, Yunqing; Chien, Siu Hung; Closser, Kristina D.; Crittenden, Deborah L.; Diedenhofen, Michael; DiStasio, Robert A., Jr.; Do, Hainam; Dutoi, Anthony D.; Edgar, Richard G.; Fatehi, Shervin; Fusti-Molnar, Laszlo; Ghysels, An; Golubeva-Zadorozhnaya, Anna; Gomes, Joseph; Hanson-Heine, Magnus W. D.; Harbach, Philipp H. P.; Hauser, Andreas W.; Hohenstein, Edward G.; Holden, Zachary C.; Jagau, Thomas-C.; Ji, Hyunjun; Kaduk, Benjamin; Khistyaev, Kirill; Kim, Jaehoon; Kim, Jihan; King, Rollin A.; Klunzinger, Phil; Kosenkov, Dmytro; Kowalczyk, Tim; Krauter, Caroline M.; Lao, Ka Un; Laurent, Adèle D.; Lawler, Keith V.; Levchenko, Sergey V.; Lin, Ching Yeh; Liu, Fenglai; Livshits, Ester; Lochan, Rohini C.; Luenser, Arne; Manohar, Prashant; Manzer, Samuel F.; Mao, Shan-Ping; Mardirossian, Narbe; Marenich, Aleksandr V.; Maurer, Simon A.; Mayhall, Nicholas J.; Neuscamman, Eric; Oana, C. Melania; Olivares-Amaya, Roberto; O'Neill, Darragh P.; Parkhill, John A.; Perrine, Trilisa M.; Peverati, Roberto; Prociuk, Alexander; Rehn, Dirk R.; Rosta, Edina; Russ, Nicholas J.; Sharada, Shaama M.; Sharma, Sandeep; Small, David W.; Sodt, Alexander; Stein, Tamar; Stück, David; Su, Yu-Chuan; Thom, Alex J. W.; Tsuchimochi, Takashi; Vanovschi, Vitalii; Vogt, Leslie; Vydrov, Oleg; Wang, Tao; Watson, Mark A.; Wenzel, Jan; White, Alec; Williams, Christopher F.; Yang, Jun; Yeganeh, Sina; Yost, Shane R.; You, Zhi-Qiang; Zhang, Igor Ying; Zhang, Xing; Zhao, Yan; Brooks, Bernard R.; Chan, Garnet K. L.; Chipman, Daniel M.; Cramer, Christopher J.; Goddard, William A., III; Gordon, Mark S.; Hehre, Warren J.; Klamt, Andreas; Schaefer, Henry F., III; Schmidt, Michael W.; Sherrill, C. David; Truhlar, Donald G.; Warshel, Arieh; Xu, Xin; Aspuru-Guzik, Alán; Baer, Roi; Bell, Alexis T.; Besley, Nicholas A.; Chai, Jeng-Da; Dreuw, Andreas; Dunietz, Barry D.; Furlani, Thomas R.; Gwaltney, Steven R.; Hsu, Chao-Ping; Jung, Yousung; Kong, Jing; Lambrecht, Daniel S.; Liang, WanZhen; Ochsenfeld, Christian; Rassolov, Vitaly A.; Slipchenko, Lyudmila V.; Subotnik, Joseph E.; Van Voorhis, Troy; Herbert, John M.; Krylov, Anna I.; Gill, Peter M. W.; Head-Gordon, Martin

2015-01-01

A summary of the technical advances that are incorporated in the fourth major release of the Q-Chem quantum chemistry program is provided, covering approximately the last seven years. These include developments in density functional theory methods and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces. In addition, a selection of example case studies that illustrate these capabilities is given. These include extensive benchmarks of the comparative accuracy of modern density functionals for bonded and non-bonded interactions, tests of attenuated second order Møller-Plesset (MP2) methods for intermolecular interactions, a variety of parallel performance benchmarks, and tests of the accuracy of implicit solvation models. Some specific chemical examples include calculations on the strongly correlated Cr2 dimer, exploring zeolite-catalysed ethane dehydrogenation, energy decomposition analysis of a charged ter-molecular complex arising from glycerol photoionisation, and natural transition orbitals for a Frenkel exciton state in a nine-unit model of a self-assembling nanotube.

Modelling Poly-Aromatic Hydrocarbons "online" with the GEOS-Chem Europe and Asia regional models.

Science.gov (United States)

Ivatt, P.; Evans, M. J.

2017-12-01

Poly-Aromatic Hydrocarbons (PAHs) are carcinogens and so are restricted by international treaties. PAHs are mainly emitted into the atmosphere by domestic (heating and cooking), natural (forest fires burning), as well as some industrial processes (coke ovens). PAHs partition between the gas and particle phase (notably carbonaceous particles) based on their volatility. In recent years, interest has turned to the possible health effects of their oxidation products (both nitrogenated and oxygenated) as it has been suggested that these oxidation products may be even more carcinogenic than the parent PAHs. To increase our understanding of the processes controlling the regional concentrations of PAHs and their oxidation products an "online" PAH model has been developed within the GEOS-Chem framework. This provides for the representation of the coupled aerosol/gas phase chemistry of the parent PAH and its secondary oxidation products. Benzo[a]pyrene is used as an exemplar but the methodology is flexible and the approach can be used for any PAH species. Comparisons are made with observations and the sources of variability discussed.

Consumer Health

Science.gov (United States)

Bibel, Barbara

2010-01-01

This article presents an annotated bibliography of 19 titles that focus on cancer and health-care reform. These include: (1) Anderson, John W. "Stand by Her: A Breast Cancer Guide for Men." AMACOM: American Management Assn.; (2) Carstensen, Laura L. "A Long Bright Future: An Action Plan for a Lifetime of Happiness, Health, and Financial Security."…

Mixed waste treatment using the ChemChar thermolytic detoxification technique

Energy Technology Data Exchange (ETDEWEB)

Kuchynka, D.

1995-12-31

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.

Mixed waste treatment using the ChemChar thermolytic detoxification technique

International Nuclear Information System (INIS)

Kuchynka, D.

1995-01-01

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. 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

The EnVision++ system: a new immunohistochemical method for diagnostics and research. Critical comparison with the APAAP, ChemMate, CSA, LABC, and SABC techniques.

Science.gov (United States)

Sabattini, E; Bisgaard, K; Ascani, S; Poggi, S; Piccioli, M; Ceccarelli, C; Pieri, F; Fraternali-Orcioni, G; Pileri, S A

1998-07-01

To assess a newly developed immunohistochemical detection system, the EnVision++. A large series of differently processed normal and pathological samples and 53 relevant monoclonal antibodies were chosen. A chessboard titration assay was used to compare the results provided by the EnVision++ system with those of the APAAP, CSA, LSAB, SABC, and ChemMate methods, when applied either manually or in a TechMate 500 immunostainer. With the vast majority of the antibodies, EnVision++ allowed two- to fivefold higher dilutions than the APAAP, LSAB, SABC, and ChemMate techniques, the staining intensity and percentage of expected positive cells being the same. With some critical antibodies (such as the anti-CD5), it turned out to be superior in that it achieved consistently reproducible results with differently fixed or overfixed samples. Only the CSA method, which includes tyramide based enhancement, allowed the same dilutions as the EnVision++ system, and in one instance (with the anti-cyclin D1 antibody) represented the gold standard. The EnVision++ is an easy to use system, which avoids the possibility of disturbing endogenous biotin and lowers the cost per test by increasing the dilutions of the primary antibodies. Being a two step procedure, it reduces both the assay time and the workload.

77 FR 12231 - Electronic On-Board Recorders and Hours of Service Supporting Documents

Science.gov (United States)

2012-02-29

... information on how to participate via the Internet on the FMCSA web site at: http://www.fmcsa.dot.gov in... Indep. Drivers Ass'n et al. v. Fed. Motor Carrier Safety Admin., 656 F.3d. 580 (7th Cir. 2011). The... be on the FMCSA Web site at http://www.fmcsa.dot.gov . FMCSA will docket the transcripts of the...

Lathe creates hardwood flakes for manufacture of "super strong" flakeboard

Science.gov (United States)

P. Koch

1973-01-01

Most industry members got their first look at a prototype of the Koch lathe at this year's Southern Forest Products Assn. Machinery Exhibition held in Atlanta. With the residue from this machine, Dr. Peter Koch, project leader at the Southern Forest Experiment Station in Pineville, LA thinks it will be possible to create a flake that can be used for making a...

Modelling of Impulsional pH Variations Using ChemFET-Based Microdevices: Application to Hydrogen Peroxide Detection

Directory of Open Access Journals (Sweden)

Abdou Karim Diallo

2014-02-01

Full Text Available This work presents the modelling of impulsional pH variations in microvolume related to water-based electrolysis and hydrogen peroxide electrochemical oxidation using an Electrochemical Field Effect Transistor (ElecFET microdevice. This ElecFET device consists of a pH-Chemical FET (pH-ChemFET with an integrated microelectrode around the dielectric gate area in order to trigger electrochemical reactions. Combining oxidation/reduction reactions on the microelectrode, water self-ionization and diffusion properties of associated chemical species, the model shows that the sensor response depends on the main influential parameters such as: (i polarization parameters on the microelectrode, i.e., voltage (Vp and time (tp; (ii distance between the gate sensitive area and the microelectrode (d; and (iii hydrogen peroxide concentration ([H2O2]. The model developed can predict the ElecFET response behaviour and creates new opportunities for H2O2-based enzymatic detection of biomolecules.

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

Directory of Open Access Journals (Sweden)

T. Sherwen

2016-02-01

Full Text Available 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  <  p  <  900 hPa over the eastern Pacific. Iodine emissions (3.8 Tg yr−1 are overwhelmingly dominated by the inorganic ocean source, with 76 % of this emission from hypoiodous acid (HOI. HOI is also found to be the dominant iodine species in terms of global tropospheric IY burden (contributing up to 70 %. The iodine chemistry leads to a significant global tropospheric O3 burden decrease (9.0 % compared to standard GEOS-Chem (v9-2. The iodine-driven OX loss rate1 (748 Tg OX yr−1 is due to photolysis of HOI (78 %, photolysis of OIO (21 %, and reaction between IO and BrO (1 %. Increases in global mean OH concentrations (1.8 % by increased conversion of hydroperoxy radicals exceeds the decrease in OH primary production from the reduced O3 concentration. We perform sensitivity studies on a range of parameters and conclude that the simulation is sensitive to choices in parametrization of heterogeneous uptake, ocean surface iodide, and I2OX (X = 2, 3, 4 photolysis. The new iodine chemistry combines with previously implemented bromine chemistry to 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

Chemical effects in 11-year solar cycle simulations with the Freie Universität Berlin Climate Middle Atmosphere Model with online chemistry (FUB-CMAM-CHEM)

OpenAIRE

U. Langematz; J. Grenfell; K. Matthes; P. Mieth; M. Kunze; B. Steil; C. Brühl;  

2005-01-01

The impact of 11-year solar cycle variations on stratospheric ozone (O3) is studied with the Freie Universität Berlin Climate Middle Atmosphere Model with interactive chemistry (FUB-CMAM-CHEM). To consider the effect of variations in charged particle precipitation we included an idealized NO x source in the upper mesosphere representing relativistic electron precipitation (REP). Our results suggest that the NO x source by particles and its transport from the mesosphere to the stratosphe...

2009 Insensitive Munitions and Energetic Materials Technology Symposium

Science.gov (United States)

2009-05-14

Government Civilian (Non-DOD/MOD) u Trade/Professional Assn. u Educator /Academia u Professional Services u Non-Defense Business u Other...synthesis; Available starting materials; Not yet commercialised Initial selection refined to 5, subsequently 3 candidates: • Oxadiazole (CL-14); hexahydro...is an integral part of OSD’s Educational Outreach Program in providing an ongoing source of scientific and engineering talent for government R&D labs

Free-market approach to energy proposed in new study

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that a free-market approach to energy use, intensified R and D and an emphasis on conservation and clean fuels such as natural gas can result in significant reductions in emissions of greenhouse gases, without any major new federal policy initiatives, according to a new study, An Alternative Energy Future, sponsored by Alliance to Save Energy, AGA and Solar Energy Industries Assn

Compliance with Community Mitigation and Interventions in Pandemic Influenza: A Community Policing Strategy

Science.gov (United States)

2007-09-01

Monica Schoch-Spana of the Bloomberg School of Public Health at Johns Hopkins University, in an article for the journal Confronting Biological Weapons ...Joseph Barbera et al., “Large-Scale Quarantine Following Biological Terrorism in the United States,” JAMA 286 (2001), http://jama.ama-assn.org/cgi/reprint...divergent practices. Mark Rothstein and others, writing for the Institute of Bioethics at the University of

77 FR 58828 - Northern Indiana Public Service Company; Notice of Petition for Declaratory Order

Science.gov (United States)

2012-09-24

..., Section 219 of the Federal Power Act (FPA) \\1\\ and Order No. 679,\\2\\ filed a petition for declaratory... Pricing Reform, Order No. 679, FERC Stats. & Regs. 31,222 (Order No. 679), order on reh'g, Order No. 679-A... dismissed sub nom., Am. Pub. Power Ass'n. v. FERC, No. 07-1050, 2007 U.S.App. LEXIS 11908 (D.C. Cir. May 14...

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 information requirements. As no testing for reproductive effects should be performed in REACH on known genotoxic carcinogens or germ cell mutagens with appropriate risk management measures implemented, a QSAR pre-screen for 70,983 REACH substances was performed. Sixteen models and three decision algorithms...... 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...

Handheld highly selective plasmonic chem/biosensor using engineered binding proteins for extreme conformational changes

Science.gov (United States)

Kosciolek, Derek J.; Sonar, Ajay; Lepak, Lori A.; Schnatz, Peter; Bendoym, Igor; Brown, Mia C.; Koder, Ronald L.; Crouse, David T.

2017-08-01

In this project we develop a handheld, portable, highly selective and sensitive chem/biosensor that has potential applications in both airborne and water-based environmental sensing. The device relies on a plasmonic chip of subwavelength-scale periodic gold rods engineered to resonate in the near infrared. The chip is functionalized with a novel class of proteins that exhibit large conformational changes upon binding to a specific target analyte. The subsequent change in local refractive index near the surface of the gold is one to two orders of magnitude greater than current conventional methods, which produces a readily measurable 5 to 10 percent difference in light transmission. This allows us to forgo traditional, bulky tabletop setups in favor of a compact form factor. Using commercially available optics to construct a transmission-based optical train, measured changes in bulk refractive index are presented here. While synthesis of binding protein efforts are focused on heme as analyte for proof of concept validation, the functionalized protein can be engineered to pair with a wide variety of analytes with minimal alterations to the plasmonic chip or device design. Such flexibility allows for this device to potentially meet the needs of first responders and health care professionals in a multitude of scenarios.

Assessing the Impact of Oil and Natural Gas Activities on Regional Air Quality in the Colorado Northern Front Range using WRF-Chem

Science.gov (United States)

Abdioskouei, M.; Carmichael, G. R.

2017-12-01

Recent increases in the Natural Gas (NG) production through hydraulic fracturing have questioned the climate benefit of switching from coal-fired to natural gas-fired power plants. Higher than expected levels of methane, VOCs, and NOx have been observed in areas close to oil and NG (OnG) operation facilities. High uncertainty in the OnG emission inventories and methane budget challenge the assessment of OnG impact on air quality and climate and consequently development of effective mitigation policies and control regulations. In this work, we focus on reducing the uncertainties around the OnG emissions by using high resolution (4x4 km2) WRF-Chem simulations coupled with detailed observation from the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ 2014) field campaign. First, we identified the optimal WRF-Chem configurations in the NFR area. We compared the performance of local and non-local Planetary Boundary Layer (PBL) schemes in predicting the PBL height and vertical mixing in the domain. We evaluated the impact of different meteorological and chemical initial and boundary conditions on the model performance. Next, simulations based on optimal configurations were used to assess the performance of the emission inventory (NEI-2011v2). To evaluate the impact of OnG emission on regional air quality and performance of NEI-2011 we tested the sensitivity of the model to the OnG emission. Comparison between simulated values and ground-based and airborne measurements shows a low bias of OnG emission in NEI-2011. Finally, inverse modeling techniques based on emission sensitivity simulations are being used to optimal scaling the OnG emission from the NEI-2011.

Ultrafine particles from power plants: Evaluation of WRF-Chem simulations with airborne measurements

Science.gov (United States)

Forkel, Renate; Junkermann, Wolfgang

2017-04-01

Ultrafine particles (UFP, particles with a diameter risk to human health and have a potential effect on climate as their presence affects the number concentration of cloud condensation nuclei. Despite of the possibly hazardous effects no regulations exist for this size class of ambient air pollution particles. While ground based continuous measurements of UFP are performed in Germany at several sites (e.g. the German Ultrafine Aerosol Network GUAN, Birmili et al. 2016, doi:10.5194/essd-8-355-2016) information about the vertical distribution of UFP within the atmospheric boundary layer is only scarce. This gap has been closed during the last years by regional-scale airborne surveys for UFP concentrations and size distributions over Germany (Junkermann et al., 2016, doi: 10.3402/tellusb.v68.29250) and Australia (Junkermann and Hacker, 2015, doi: 10.3402/tellusb.v67.25308). Power stations and refineries have been identified as a major source of UFP in Germany with observed particle concentrations > 50000 particles cm-3 downwind of these elevated point sources. Nested WRF-Chem simulations with 2 km grid width for the innermost domain are performed with UFP emission source strengths derived from the measurements in order to study the advection and vertical exchange of UFP from power plants near the Czech and Polish border and their impact on planetary boundary layer particle patterns. The simulations are evaluated against the airborne observations and the downward mixing of the UFP from the elevated sources is studied.

Clinical Investigation Program Report, RCS MED-300 (R1).

Science.gov (United States)

1986-10-31

handpieces . Technical Approach: The study will be conducted in vitro using the palatal roots of human maxillary molar teeth which previously extracted due...109 1985 Histoplasmosis Seroconversion Study. (T) 110 1986 A Comparative Study of Fetal Movement Perceptions in the Third Trimester of Multiparous and...Hartwell G, Portell FR: Clinical management of middle mesial root canals in mandibular molars : Two case reports. Submitted to J Am Dent Assn. DeFiore

Catalog of Completed Studies, US Army Health Care Studies and Clinical Investigation Activity.

Science.gov (United States)

1984-12-10

Arch. Dermatol, 1980, 116:559-561. 16 Becker, L. E. Charles, C. R., Babcock, W. S., Electrol microscopic diagnosis of lymphogranuloma venereum , J. Assn...852. 3 Becker, L. E., Skipworth, G. B., Ginkgo-tree dermatitis, stomatitis, and proctitis. JAMA, 1975, 231:1162-1163. 4 Becker, L. E., Lymphogranuloma ... venereum . Intl. J. Dermatol, 1976, 15:26-33 5 Jessen, R. T., Straight, M., Becker, L. E., Lichen myxedematosus. Treatment with cyclophosphamide. Int

A Qualitative Study of Affordability: Virginia and San Antonio Class Programs

Science.gov (United States)

2014-06-01

that actual costs and operational tempos resemble original assumptions is the most uncertain aspect of sustainment costs. Operators must respond to a...SSN 774 through SSN 787; this represents 47% of the total inventory, a typical variation for ships from the acquisition standard of 10%. Even... Goldberg , M., … MacKinnon, M. (1994). The U.S. submarine production base (MR-456-OSD). Santa Monica, CA: RAND. Blickstein, I. United States. Department

Magnetoelectric Transverse Gradient Sensor with High Detection Sensitivity and Low Gradient Noise.

Science.gov (United States)

Zhang, Mingji; Or, Siu Wing

2017-10-25

We report, theoretically and experimentally, the realization of a high detection performance in a novel magnetoelectric (ME) transverse gradient sensor based on the large ME effect and the magnetic field gradient (MFG) technique in a pair of magnetically-biased, electrically-shielded, and mechanically-enclosed ME composites having a transverse orientation and an axial separation. The output voltage of the gradient sensor is directly obtained from the transverse MFG-induced difference in ME voltage between the two ME composites and is calibrated against transverse MFGs to give a high detection sensitivity of 0.4-30.6 V/(T/m), a strong common-mode magnetic field noise rejection rate of gradient noise of 0.16-620 nT/m/ Hz in a broad frequency range of 1 Hz-170 kHz under a small baseline of 35 mm. An analysis of experimental gradient noise spectra obtained in a magnetically-unshielded laboratory environment reveals the domination of the pink (1/ f ) noise, dielectric loss noise, and power-frequency noise below 3 kHz, in addition to the circuit noise above 3 kHz, in the gradient sensor. The high detection performance, together with the added merit of passive and direct ME conversion by the large ME effect in the ME composites, makes the gradient sensor suitable for the passive, direct, and broadband detection of transverse MFGs.

Part I: Reverse-docking studies of a squaramide-catalyzed conjugate addition of a diketone to a nitro-olefin Part II: The development of ChemSort: an education game for organic chemistry

Science.gov (United States)

Granger, Jenna Christine

Part 1: Reverse-docking studies of a squaramide-catalyzed conjugate addition of a diketone to a nitro-olefin. Asymmetric organocatalysis, the catalysis of asymmetric reactions by small organic molecules, is a rapidly growing field within organic synthesis. The ability to rationally design organocatalysts is therefore of increasing interest to organic chemists. Computational chemistry is quickly proving to be an extremely successful method for understanding and predicting the roles of organocatalysts, and therefore is certain to be of use in the rational design of such catalysts. A methodology for reverse-docking flexible organocatalysts to rigid transition state models of asymmetric reactions has been previously developed by the Deslongchamps group. The investigation of Rawal's squaramide-based organocatalyst for the addition of a diketone to a nitro-olefin is described, and the results of the reverse docking of Rawal's catalyst to the geometry optimized transition state models of the uncatalyzed reaction for both the R and S-product enantiomers are presented. The results of this study indicate a preference for binding of the organocatalyst to the R-enantiomer transition state model with a predicted enantiomeric excess of 99%, which is consistent with the experimental results. A plausible geometric model of the transition state for the catalyzed reaction is also presented. The success of this study demonstrates the credibility of using reverse docking methods for the rational design of asymmetric organocatalysts. Part 2: The development of ChemSort: an educational game for organic chemistry. With the advent of the millennial learner, we need to rethink traditional classroom approaches to science learning in terms of goals, approaches, and assessments. Digital simulations and games hold much promise in support of this educational shift. Although the idea of using games for education is not a new one, well-designed computer-based "serious games" are only beginning to

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

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.

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)

Fabre, C.; Cousin, A.; Wiens, R.C.; Ollila, A.; Gasnault, O.; Maurice, S.; Sautter, V.; Forni, O.; Lasue, J.; Tokar, R.; Vaniman, D.; Melikechi, N.

2014-01-01

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 2 estimates using univariate cannot be yet used. Na 2 O and K 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 2 O 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 rapid tool along the

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

Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database

Science.gov (United States)

Clegg, Samuel M.; Wiens, Roger C.; Anderson, Ryan; Forni, Olivier; Frydenvang, Jens; Lasue, Jeremie; Cousin, Agnes; Payre, Valerie; Boucher, Tommy; Dyar, M. Darby; McLennan, Scott M.; Morris, Richard V.; Graff, Trevor G.; Mertzman, Stanley A; Ehlmann, Bethany L.; Belgacem, Ines; Newsom, Horton E.; Clark, Ben C.; Melikechi, Noureddine; Mezzacappa, Alissa; McInroy, Rhonda E.; Martinez, Ronald; Gasda, Patrick J.; Gasnault, Olivier; Maurice, Sylvestre

2017-01-01

The ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) instrument onboard the Mars Science Laboratory (MSL) rover Curiosity has obtained > 300,000 spectra of rock and soil analysis targets since landing at Gale Crater in 2012, and the spectra represent perhaps the largest publicly-available LIBS datasets. The compositions of the major elements, reported as oxides (SiO2, TiO2, Al2O3, FeOT, MgO, CaO, Na2O, K2O), have been re-calibrated using a laboratory LIBS instrument, Mars-like atmospheric conditions, and a much larger set of standards (408) that span a wider compositional range than previously employed. The new calibration uses a combination of partial least squares (PLS1) and Independent Component Analysis (ICA) algorithms, together with a calibration transfer matrix to minimize differences between the conditions under which the standards were analyzed in the laboratory and the conditions on Mars. While the previous model provided good results in the compositional range near the average Mars surface composition, the new model fits the extreme compositions far better. Examples are given for plagioclase feldspars, where silicon was significantly over-estimated by the previous model, and for calcium-sulfate veins, where silicon compositions near zero were inaccurate. The uncertainties of major element abundances are described as a function of the abundances, and are overall significantly lower than the previous model, enabling important new geochemical interpretations of the data.

Chem-Prep PZT 95/5 for Neutron Generator Applications: Particle Size Distribution Comparison of Development and Production-Scale Powders

International Nuclear Information System (INIS)

SIPOLA, DIANA L.; VOIGT, JAMES A.; LOCKWOOD, STEVEN J.; RODMAN-GONZALES, EMILY D.

2002-01-01

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

Spatio-temporal variability of CO and O3 in Hyderabad (17°N, 78°E, central India, based on MOZAIC and TES observations and WRF-Chem and MOZART-4 models

Directory of Open Access Journals (Sweden)

Varun Sheel

2016-05-01

Full Text Available This article is based on the study of the seasonal and interannual variability of carbon monoxide (CO and ozone (O3 at different altitudes of the troposphere over Hyderabad, India, during 2006–2010 using Measurement of OZone and water vapour by Airbus In-Service Aircraft (MOZAIC and observation from Tropospheric Emission Spectrometer (TES aboard NASA's Aura satellite. The MOZAIC observations show maximum seasonal variability in both CO and O3 during winter and pre-monsoon season, with CO in the range (100–200±13 ppbv and O3 in the range (50–70±9 ppbv. The time-series of MOZAIC data shows a significant increase of 4.2±1.3 % in the surface CO and 6.7±1.3 % in the surface O3 during 2006–2010 in Hyderabad. From MOZAIC observations, we identify CO and O3 profiles that are anomalous with respect to the monthly mean and compare those with Weather Research Forecast model coupled with Chemistry (WRF-Chem and Model for OZone and Related Tracers, version 4 profiles for the same day. The anomalous profiles of WRF-Chem are simulated using three convection schemes. The goodness of comparison depends on the convection scheme and the altitude region of the troposphere.

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

Full Text Available Liquid-phase pKa values play a key role in food science. Chemical properties of molecules depend largely on whether they are ionized or not. Most organic molecules are capable of gaining and/or losing a proton in aqueous solutions. Proton transfer most. frequently occurs between water and any ionizable atom of the organic molecule. The molecule’s response to profanation or deprotonation depends significantly on the site that was disturbed by proton transfer. Partial charge distribution in the molecule also varies with protonation of the acidlbase active sites. Then it can he used to determine the pKa of a molecule. First, we use the COSMO-RS method, a combination of the quantum chemical dielectric continuum solvation model COSMO with a statistical thermodynamics treatment fin- more Realistic Solvation (RS simulations, for the direct prediction of pKa constants of about 50 molecules (amino-acids, dipeptides and tripeptides. Then, we compare our results with experimental data and the pKa values predicted using two other methods. We used respectively the ChemAxon method using a program based on the calculation of partial charge of atoms in the molecule and the ACD/Labs method that enables to calculate single pKa values. for all possible dissociation centers when the rest of the molecule is considered neutral, using an internal database containing chemical structures and their experimental pKa values. The averaged Root Mean Square Error (RMSE of the predicted pKa values for each method compared to experimental results were respectively 0.596 for COSMO-RS, 0.445 for ChemAxon and 0.490 for ACD/Labs. While ACDILabs and ChemAxon are parameterized using a large set ofexperimental data (including several of the studied molecules, the COSMO- RS method was used in a fully predictive way. Regarding these results, COSMO-RS appears as a promising method to predict the pKa values of molecules of interest in food science with scarce available pKa values such

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

Science.gov (United States)

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; Lasue, Jeremie; Anderson, Ryan; McLennan, Scott M.; Bridges, John; Vaniman, Dave; Lanza, Nina; Fabre, Cecile; Melikechi, Noureddine; Perett, Glynis M.; Campbell, John L.; King, Penelope L.; Barraclough, Bruce; Delapp, Dorothea; Johnstone, Stephen; Meslin, Pierre-Yves; Rosen-Gooding, Anya; Williams, Josh

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 directly on Mars, is generally low (100 ppm and >1000 ppm, respectively. These analysis locations tend to have high Si and alkali abundances, consistent with a feldspar composition. Together, these trace element observations provide possible evidence of magma differentiation and aqueous alteration.

Application of WRF/Chem over the Continental U.S. under the AQMEII Phase II: Part 2. Evaluation of 2010 Application and Responses of Air Quality and Meteorology-Chemistry Interactions to Changes in Emissions and Meteorology from 2006 to 2010

Science.gov (United States)

The Weather Research and Forecasting model with Chemistry (WRF/Chem) simulation with the 2005 Carbon Bond (CB05) gas-phase mechanism coupled to the Modal for Aerosol Dynamics for Europe (MADE) and the Volatility Basis Set (VBS) approach for secondary organic aerosol (SOA) (MADE/V...

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

Radiative effects of black carbon aerosols on Indian monsoon: a study using WRF-Chem model

Science.gov (United States)

Soni, Pramod; Tripathi, Sachchida Nand; Srivastava, Rajesh

2018-04-01

The Weather Research and Forecasting model with Chemistry (WRF-Chem) is utilized to examine the radiative effects of black carbon (BC) aerosols on the Indian monsoon, for the year 2010. Five ensemble simulations with different initial conditions (1st to 5th December, 2009) were performed and simulation results between 1st January, 2010 to 31st December, 2010 were used for analysis. Most of the BC which stays near the surface during the pre-monsoon season gets transported to higher altitudes with the northward migration of the Inter Tropical Convergence Zone (ITCZ) during the monsoon season. In both the seasons, strong negative SW anomalies are present at the surface along with positive anomalies in the atmosphere, which results in the surface cooling and lower tropospheric heating, respectively. During the pre-monsoon season, lower troposphere heating causes increased convection and enhanced meridional wind circulation, bringing moist air from Indian Ocean and Bay of Bengal to the North-East India, leading to increased rainfall there. However, during the monsoon season, along with cooling over the land regions, a warming over the Bay of Bengal is simulated. This differential heating results in an increased westerly moisture flux anomaly over central India, leading to increased rainfall over northern parts of India but decreased rainfall over southern parts. Decreased rainfall over southern India is also substantiated by the presence of increased evaporation over Bay of Bengal and decrease over land regions.

Medicare, physicians, and patients.

Science.gov (United States)

Hacker, Joseph F

2004-05-01

There are many other provisions to the MMA. It is important to remind our patients that these changes are voluntary. If patients are satisfied with their current Medicare benefits and plan, they need not change to these new plans. However, as physicians we should familiarize ourselves with these new Medicare options so as to better advise our patients. For more information, visit www.ama-assn.org. The Medical Society of Delaware will strive to keep you informed as these new changes are implemented.

A WRF-Chem model study of the impact of VOCs emission of a huge petro-chemical industrial zone on the summertime ozone in Beijing, China

Science.gov (United States)

Wei, Wei; Lv, Zhao Feng; Li, Yue; Wang, Li Tao; Cheng, Shuiyuan; Liu, Huan

2018-02-01

In China, petro-chemical manufacturing plants generally gather in the particular industrial zone defined as PIZ in some cities, and distinctly influence the air quality of these cities for their massive VOCs emissions. This study aims to quantify the local and regional impacts of PIZ VOCs emission and its relevant reduction policy on the surface ozone based on WRF-Chem model, through the case study of Beijing. Firstly, the model simulation under the actual precursors' emissions over Beijing region for July 2010 is conducted and evaluated, which meteorological and chemical predictions both within the thresholds for satisfactory model performance. Then, according to simulated H2O2/HNO3 ratio, the nature of photochemical ozone formation over Beijing is decided, the VOCs-sensitive regime over the urban areas, NOx-sensitive regime over the northern and western rural areas, and both VOCssbnd and NOx-mixed sensitive regime over the southern and eastern rural areas. Finally, a 30% VOCs reduction scenario (RS) and a 100% VOCs reduction scenario (ZS) for Beijing PIZ are additional simulated by WRF-Chem. The sensitivity simulations imply that the current 30% reduction policy would bring about an O3 increase in the southern and western areas (by +4.7 ppb at PIZ site and +2.1 ppb at LLH station), and an O3 decrease in the urban center (by -1.7 ppb at GY station and -2.5 ppb at DS station) and in the northern and eastern areas (by -1.2 ppb at MYX station), mainly through interfering with the circulation of atmospheric HOx radicals. While the contribution of the total VOCs emission of PIZ to ozone is greatly prominent in the PIZ and its surrounding areas along south-north direction (12.7% at PIZ site on average), but slight in the other areas of Beijing (<3% in other four stations on average).

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.

Quantifying sources of elemental carbon over the Guanzhong Basin of China: A consistent network of measurements and WRF-Chem modeling

International Nuclear Information System (INIS)

Li, Nan; He, Qingyang; Tie, Xuexi; Cao, Junji; Liu, Suixin; Wang, Qiyuan; Li, Guohui; Huang, Rujin; Zhang, Qiang

2016-01-01

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. - Highlights: • A yearlong WRF-Chem simulation is conducted to identify sources of the EC pollution. • A network of

Modeling regional air quality and climate: improving organic aerosol and aerosol activation processes in WRF/Chem version 3.7.1

Science.gov (United States)

Yahya, Khairunnisa; Glotfelty, Timothy; Wang, Kai; Zhang, Yang; Nenes, Athanasios

2017-06-01

Air quality and climate influence each other through the uncertain processes of aerosol formation and cloud droplet activation. In this study, both processes are improved in the Weather, Research and Forecasting model with Chemistry (WRF/Chem) version 3.7.1. The existing Volatility Basis Set (VBS) treatments for organic aerosol (OA) formation in WRF/Chem are improved by considering the following: the secondary OA (SOA) formation from semi-volatile primary organic aerosol (POA), a semi-empirical formulation for the enthalpy of vaporization of SOA, and functionalization and fragmentation reactions for multiple generations of products from the oxidation of VOCs. Over the continental US, 2-month-long simulations (May to June 2010) are conducted and results are evaluated against surface and aircraft observations during the Nexus of Air Quality and Climate Change (CalNex) campaign. Among all the configurations considered, the best performance is found for the simulation with the 2005 Carbon Bond mechanism (CB05) and the VBS SOA module with semivolatile POA treatment, 25 % fragmentation, and the emissions of semi-volatile and intermediate volatile organic compounds being 3 times the original POA emissions. Among the three gas-phase mechanisms (CB05, CB6, and SAPRC07) used, CB05 gives the best performance for surface ozone and PM2. 5 concentrations. Differences in SOA predictions are larger for the simulations with different VBS treatments (e.g., nonvolatile POA versus semivolatile POA) compared to the simulations with different gas-phase mechanisms. Compared to the simulation with CB05 and the default SOA module, the simulations with the VBS treatment improve cloud droplet number concentration (CDNC) predictions (normalized mean biases from -40.8 % to a range of -34.6 to -27.7 %), with large differences between CB05-CB6 and SAPRC07 due to large differences in their OH and HO2 predictions. An advanced aerosol activation parameterization based on the Fountoukis and Nenes

Evaluation of aerosol optical properties of GEOS-Chem over East Asia during the DRAGON-Asia 2012 campaign

Science.gov (United States)

Jo, D. S.; Park, R.; Kim, J.

2015-12-01

A nested version of 3-D chemical transport model (GEOS-Chem v9-01-02) is evaluated over East Asia during the Distributed Regional Aerosol Gridded Observation Networks (DRAGON)-Asia 2012 campaign period, focusing on fine-mode aerosol optical depth (fAOD) and single scattering albedo (SSA). Both are important to assess the effect of anthropogenic aerosols on climate. We compare the daily mean simulated optical properties of aerosols with the observations from DRAGON-Asia campaign for March-May, 2012 (provided in level 2.0: cloud screened and quality assured). We find that the model reproduces the observed daily variability of fAOD (R=0.67), but overestimates the magnitude by 30%, which is in general consistent with other global model comparisons from ACCMIP. However, a significant high bias in the model is found compared to the observed SSA at 440 nm, which is important for determining the sign of aerosol radiative forcing. In order to understand causes for this gap we conduct several sensitivity tests by changing source magnitudes and input parameters of aerosols, affecting the aerosol optical properties under various atmospheric conditions, which allows us to reduce the gap and to find the optimal values in the model.

Structural changes in microferrogels cross-linked by magnetically anisotropic particles

Energy Technology Data Exchange (ETDEWEB)

Ryzhkov, A.V., E-mail: ryzhkov.a@icmm.ru [Perm National Research Polytechnic University, Perm 614990 (Russian Federation); Institute of Continuous Media Mechanics, Russian Academy of Sciences, Ural Branch, Perm 614013 (Russian Federation); Raikher, Yu. L. [Institute of Continuous Media Mechanics, Russian Academy of Sciences, Ural Branch, Perm 614013 (Russian Federation)

2017-06-01

Chaining of magnetic nanoparticles in a microscopic ferrogel (MFG) due to interparticle interaction and external field is analyzed by the coarse-grained molecular dynamics. The embedded nanoparticles, unlike existing conventional models, are assumed to possess uniaxial magnetic anisotropy. By that, the consideration is brought closer to reality. Evolution of particle chains, both in length and straightness, is handled with the aid of “axial” radial distribution function that is sensitive to orientation of the aggregates. The effect of the particle magnetic anisotropy on the structural alterations as well as on volume changes of MFGs is demonstrated.

Accounting for model error in air quality forecasts: an application of 4DEnVar to the assimilation of atmospheric composition using QG-Chem 1.0

Directory of Open Access Journals (Sweden)

E. Emili

2016-11-01

Full Text Available Model errors play a significant role in air quality forecasts. Accounting for them in the data assimilation (DA procedures is decisive to obtain improved forecasts. We address this issue using a reduced-order coupled chemistry–meteorology model based on quasi-geostrophic dynamics and a detailed tropospheric chemistry mechanism, which we name QG-Chem. This model has been coupled to the software library for the data assimilation Object Oriented Prediction System (OOPS and used to assess the potential of the 4DEnVar algorithm for air quality analyses and forecasts. The assets of 4DEnVar include the possibility to deal with multivariate aspects of atmospheric chemistry and to account for model errors of a generic type. A simple diagnostic procedure for detecting model errors is proposed, based on the 4DEnVar analysis and one additional model forecast. A large number of idealized data assimilation experiments are shown for several chemical species of relevance for air quality forecasts (O3, NOx, CO and CO2 with very different atmospheric lifetimes and chemical couplings. Experiments are done both under a perfect model hypothesis and including model error through perturbation of surface chemical emissions. Some key elements of the 4DEnVar algorithm such as the ensemble size and localization are also discussed. A comparison with results of 3D-Var, widely used in operational centers, shows that, for some species, analysis and next-day forecast errors can be halved when model error is taken into account. This result was obtained using a small ensemble size, which remains affordable for most operational centers. We conclude that 4DEnVar has a promising potential for operational air quality models. We finally highlight areas that deserve further research for applying 4DEnVar to large-scale chemistry models, i.e., localization techniques, propagation of analysis covariance between DA cycles and treatment for chemical nonlinearities. QG-Chem can provide a

Using WRF-Chem to investigate the impact of night time nitrate radical chemistry and N2O5 heterogeneous chemistry on the chemical composition of the UK troposphere.

Science.gov (United States)

Archer-Nicholls, S.; Lowe, D.; Utembe, S.; McFiggans, G.

2012-04-01

It is believed that NO3 is the primary oxidant at night time, significantly impacting ozone formation, rain acidification and the formation and transformation of aerosols, particularly through the formation of the ammonium nitrate particulate (Allan et. al., 2000). However, many of the basic chemical processes controlling the formation and removal of NO3, in particular, the N2O5 heterogeneous reactions, are often not represented in models, although general parameterisations have been developed (c.f. Bertram & Thornton, 2009). The ROle of Night time chemistry in controlling the Oxidising Capacity of the atmOsphere (RONOCO) campaign is a project being funded by NERC and being carried out by a collaboration of UK Universities. It aims to better understand the role of the NO3 radical on the chemistry of the night time atmosphere, its oxidation capacity and thus its overall effects on the composition of the troposphere. The Weather Research and Forecasting model with Chemistry (WRF-Chem) is a state of the art regional climate model with fully coupled online air quality and meteorological components allowing for better resolution of aerosol and gas-phase chemistry (Grell et. al., 2005). It has been extended to include the Common Representative Intermediates scheme (CRIv2-R5) (Watson et. al., 2008), a reduced chemical scheme designed to simulate the atmospheric degradation of 220 species of hydrocarbons and VOCs. The MOSAIC aerosol scheme (Zaveri et. al., 2008), has been extended to include a reduced complexity condensed organic phase consisting of 13 semi-volatile and 2 involatile species (Topping et. al., 2012), as well as the N2O5 heterogeneous reaction scheme of Bertram & Thornton (2009). We aim to use WRF-Chem to compare the oxidation capacity of nighttime NO3 chemistry with that of daytime OH chemistry. The model was run using two nested grids: a 15km resolution domain over western Europe, containing a 5km resolution domain over the UK. The RONOCO campaign consisted

Impact of vehicular emissions on the formation of fine particles in the Sao Paulo Metropolitan Area: a numerical study with the WRF-Chem model

Directory of Open Access Journals (Sweden)

A. Vara-Vela

2016-01-01

Full Text Available 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

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

Simulation of West African air pollution during the DACCIWA experiment with the GEOS-Chem West African regional model.

Science.gov (United States)

Morris, Eleanor; Evans, Mathew

2017-04-01

Pollutant emissions from West African cities are forecast to increase rapidly in future years because of extensive economic and population growth, together with poorly regulated industrialisation and urbanisation. Observational constraints in this region are few, leading to poor understanding of present-day air pollution in this region. To increase our understanding of the processes controlling air pollutants over the region, airborne observations were made from three research aircraft based out of Lomé, Togo during the DACCIWA field campaign in June-July 2016. A new 0.25x0.3125 degree West Africa regional version of the GEOS-Chem offline chemical transport model has also been developed to explore the processes controlling pollutants over the region. We evaluate the model using the aircraft data and focus on primary (CO, SO2, NOx, VOCs) and secondary pollutants (O3, aerosol). We find significant differences between the model and the measurements for certain primary compounds which is indicative of significant uncertainties in the base (EDGAR) emissions. For CO (a general tracer of pollution) we evaluate the role of different emissions sources (transport, low temperature combustion, power generation) in determining its concentration in the region. We conclude that the leading cause of uncertainty in our simulation is associated with the emissions datasets and explore the impact of using differing datasets.

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.

Modeling regional air quality and climate: improving organic aerosol and aerosol activation processes in WRF/Chem version 3.7.1

Directory of Open Access Journals (Sweden)

K. Yahya

2017-06-01

Full Text Available Air quality and climate influence each other through the uncertain processes of aerosol formation and cloud droplet activation. In this study, both processes are improved in the Weather, Research and Forecasting model with Chemistry (WRF/Chem version 3.7.1. The existing Volatility Basis Set (VBS treatments for organic aerosol (OA formation in WRF/Chem are improved by considering the following: the secondary OA (SOA formation from semi-volatile primary organic aerosol (POA, a semi-empirical formulation for the enthalpy of vaporization of SOA, and functionalization and fragmentation reactions for multiple generations of products from the oxidation of VOCs. Over the continental US, 2-month-long simulations (May to June 2010 are conducted and results are evaluated against surface and aircraft observations during the Nexus of Air Quality and Climate Change (CalNex campaign. Among all the configurations considered, the best performance is found for the simulation with the 2005 Carbon Bond mechanism (CB05 and the VBS SOA module with semivolatile POA treatment, 25 % fragmentation, and the emissions of semi-volatile and intermediate volatile organic compounds being 3 times the original POA emissions. Among the three gas-phase mechanisms (CB05, CB6, and SAPRC07 used, CB05 gives the best performance for surface ozone and PM2. 5 concentrations. Differences in SOA predictions are larger for the simulations with different VBS treatments (e.g., nonvolatile POA versus semivolatile POA compared to the simulations with different gas-phase mechanisms. Compared to the simulation with CB05 and the default SOA module, the simulations with the VBS treatment improve cloud droplet number concentration (CDNC predictions (normalized mean biases from −40.8 % to a range of −34.6 to −27.7 %, with large differences between CB05–CB6 and SAPRC07 due to large differences in their OH and HO2 predictions. An advanced aerosol activation

Global impacts of tropospheric halogens (Cl, Br, I on oxidants and composition in GEOS-Chem

Directory of Open Access Journals (Sweden)

T. Sherwen

2016-09-01

Full Text Available We present a simulation of the global present-day composition of the troposphere which includes the chemistry of halogens (Cl, Br, I. Building on previous work within the GEOS-Chem model we include emissions of inorganic iodine from the oceans, anthropogenic and biogenic sources of halogenated gases, gas phase chemistry, and a parameterised approach to heterogeneous halogen chemistry. Consistent with Schmidt et al. (2016 we do not include sea-salt debromination. Observations of halogen radicals (BrO, IO are sparse but the model has some skill in reproducing these. Modelled IO shows both high and low biases when compared to different datasets, but BrO concentrations appear to be modelled low. Comparisons to the very sparse observations dataset of reactive Cl species suggest the model represents a lower limit of the impacts of these species, likely due to underestimates in emissions and therefore burdens. Inclusion of Cl, Br, and I results in a general improvement in simulation of ozone (O3 concentrations, except in polar regions where the model now underestimates O3 concentrations. Halogen chemistry reduces the global tropospheric O3 burden by 18.6 %, with the O3 lifetime reducing from 26 to 22 days. Global mean OH concentrations of 1.28  ×  106 molecules cm−3 are 8.2 % lower than in a simulation without halogens, leading to an increase in the CH4 lifetime (10.8 % due to OH oxidation from 7.47 to 8.28 years. Oxidation of CH4 by Cl is small (∼  2 % but Cl oxidation of other VOCs (ethane, acetone, and propane can be significant (∼  15–27 %. Oxidation of VOCs by Br is smaller, representing 3.9 % of the loss of acetaldehyde and 0.9 % of the loss of formaldehyde.

ODM2 (Observation Data Model): The EarthChem Use Case

Science.gov (United States)

Lehnert, Kerstin; Song, Lulin; Hsu, Leslie; Horsburgh, Jeffrey S.; Aufdenkampe, Anthony K.; Mayorga, Emilio; Tarboton, David; Zaslavsky, Ilya

2014-05-01

PetDB is an online data system that was created in the late 1990's to serve online a synthesis of published geochemical and petrological data of igneous and metamorphic rocks. PetDB has today reached a volume of 2.5 million analytical values for nearly 70,000 rock samples. PetDB's data model (Lehnert et al., G-Cubed 2000) was designed to store sample-based observational data generated by the analysis of rocks, together with a wide range of metadata documenting provenance of the samples, analytical procedures, data quality, and data source. Attempts to store additional types of geochemical data such as time-series data of seafloor hydrothermal springs and volcanic gases, depth-series data for marine sediments and soils, and mineral or mineral inclusion data revealed the limitations of the schema: the inability to properly record sample hierarchies (for example, a garnet that is included in a diamond that is included in a xenolith that is included in a kimberlite rock sample), inability to properly store time-series data, inability to accommodate classification schemes other than rock lithologies, deficiencies of identifying and documenting datasets that are not part of publications. In order to overcome these deficiencies, PetDB has been developing a new data schema using the ODM2 information model (ODM=Observation Data Model). The development of ODM2 is a collaborative project that leverages the experience of several existing information representations, including PetDB and EarthChem, and the CUAHSI HIS Observations Data Model (ODM), as well as the general specification for encoding observational data called Observations and Measurements (O&M) to develop a uniform information model that seamlessly manages spatially discrete, feature-based earth observations from environmental samples and sample fractions as well as in-situ sensors, and to test its initial implementation in a variety of user scenarios. The O&M model, adopted as an international standard by the Open

ChemView

Data.gov (United States)

U.S. Environmental Protection Agency — Search tool developed to provide stakeholders access to various TSCA chemicals, and health and safety information. The tool also provides EPA assessments and actions...

Radiative effects of light-absorbing particles deposited in snow over Himalayas using WRF-Chem simulations

Science.gov (United States)

Sarangi, C.; Qian, Y.; Painter, T. H.; Liu, Y.; Lin, G.; Wang, H.

2017-12-01

Radiative forcing induced by light-absorbing particles (LAP) deposited on snow is an important surface forcing. It has been debated that an aerosol-induced increase in atmospheric and surface warming over Tibetan Plateau (TP) prior to the South Asian summer monsoon can have a significant effect on the regional thermodynamics and South Asian monsoon circulation. However, knowledge about the radiative effects due to deposition of LAP in snow over TP is limited. In this study we have used a high-resolution WRF-Chem (coupled with online chemistry and snow-LAP-radiation model) simulations during 2013-2014 to estimate the spatio-temporal variation in LAP deposition on snow, specifically black carbon (BC) and dust particles, in Himalayas. Simulated distributions in meteorology, aerosol concentrations, snow albedo, snow grain size and snow depth are evaluated against satellite and in-situ measurements. The spatio-temporal change in snow albedo and snow grain size with variation in LAP deposition is investigated and the resulting shortwave LAP radiative forcing at surface is calculated. The LAP-radiative forcing due to aerosol deposition, both BC and dust, is higher in magnitude over Himalayan slopes (terrain height below 4 km) compared to that over TP (terrain height above 4 km). We found that the shortwave aerosol radiative forcing efficiency at surface due to increase in deposited mass of BC particles in snow layer ( 25 (W/m2)/ (mg/m2)) is manifold higher than the efficiency of dust particles ( 0.1 (W/m2)/ (mg/m2)) over TP. However, the radiative forcing of dust deposited in snow is similar in magnitude (maximum 20-30 W/m2) to that of BC deposited in snow over TP. This is mainly because the amount of dust deposited in snow over TP can be about 100 times greater than the amount of BC deposited in snow during polluted conditions. The impact of LAP on surface energy balance, snow melting and atmospheric thermodynamics is also examined.

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, Jill 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.

Brimstone chemistry under laser light assists mass spectrometric detection and imaging the distribution of arsenic in minerals.

Science.gov (United States)

Lal, Swapnil; Zheng, Zhaoyu; Pavlov, Julius; Attygalle, Athula B

2018-05-23

Singly charged As2n+1 ion clusters (n = 2-11) were generated from elemental arsenic by negative-ion laser-ablation mass spectrometry. The overall abundance of the gaseous As ions generated upon laser irradiation was enhanced nearly a hundred times when As-bearing samples were admixed with sulfur. However, sulfur does not act purely as an inert matrix: irradiating arsenic-sulfur mixtures revealed a novel pathway to generate and detect a series of [AsSn]- clusters (n = 2-6). Intriguingly, the spectra recorded from As2O3, NaAsO2, Na3AsO4, cacodylic acid and 3-amino-4-hydroxyphenylarsonic acid together with sulfur as the matrix were remarkably similar to that acquired from an elemental arsenic and sulfur mixture. This result indicated that arsenic sulfide cluster-ions are generated directly from arsenic compounds by a hitherto unknown pathway. The mechanism of elemental sulfur extracting chemically bound arsenic from compounds and forming [AsSn]- clusters is enigmatic; however, this discovery has a practical value as a general detection method for arsenic compounds. For example, the method was employed for the detection of As in its minerals, and for the imaging of arsenic distribution in minerals such as domeykite. LDI-MS data recorded from a latent image imprinted on a piece of paper from a flat mineral surface, and wetting the paper with a solution of sulfur, enabled the localization of arsenic in the mineral. The distribution of As was visualized as false-color images by extracting from acquired data the relative intensities of m/z 139 (AsS2-) and m/z 171 (AsS3-) ions.

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

International Nuclear Information System (INIS)

Pop, M.G.; Riddle, J.M.; Lamanna, L.S.; Gregorich, C.; Hoornik, A.

2015-01-01

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 NobleChem TM (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)

Contributions of mobile, stationary and biogenic sources to air pollution in the Amazon rainforest: a numerical study with the WRF-Chem model

Science.gov (United States)

Abou Rafee, Sameh A.; Martins, Leila D.; Kawashima, Ana B.; Almeida, Daniela S.; Morais, Marcos V. B.; Souza, Rita V. A.; Oliveira, Maria B. L.; Souza, Rodrigo A. F.; Medeiros, Adan S. S.; Urbina, Viviana; Freitas, Edmilson D.; Martin, Scot T.; Martins, Jorge A.

2017-06-01

This paper evaluates the contributions of the emissions from mobile, stationary and biogenic sources on air pollution in the Amazon rainforest by using the Weather Research and Forecasting with Chemistry (WRF-Chem) model. The analyzed air pollutants were CO, NOx, SO2, O3, PM2. 5, PM10 and volatile organic compounds (VOCs). Five scenarios were defined in order to evaluate the emissions by biogenic, mobile and stationary sources, as well as a future scenario to assess the potential air quality impact of doubled anthropogenic emissions. The stationary sources explain the highest concentrations for all air pollutants evaluated, except for CO, for which the mobile sources are predominant. The anthropogenic sources considered resulted an increasing in the spatial peak-temporal average concentrations of pollutants in 3 to 2780 times in relation to those with only biogenic sources. The future scenario showed an increase in the range of 3 to 62 % in average concentrations and 45 to 109 % in peak concentrations depending on the pollutant. In addition, the spatial distributions of the scenarios has shown that the air pollution plume from the city of Manaus is predominantly transported west and southwest, and it can reach hundreds of kilometers in length.

Contributions of mobile, stationary and biogenic sources to air pollution in the Amazon rainforest: a numerical study with the WRF-Chem model

Directory of Open Access Journals (Sweden)

S. A. Abou Rafee

2017-06-01

Full Text Available This paper evaluates the contributions of the emissions from mobile, stationary and biogenic sources on air pollution in the Amazon rainforest by using the Weather Research and Forecasting with Chemistry (WRF-Chem model. The analyzed air pollutants were CO, NOx, SO2, O3, PM2. 5, PM10 and volatile organic compounds (VOCs. Five scenarios were defined in order to evaluate the emissions by biogenic, mobile and stationary sources, as well as a future scenario to assess the potential air quality impact of doubled anthropogenic emissions. The stationary sources explain the highest concentrations for all air pollutants evaluated, except for CO, for which the mobile sources are predominant. The anthropogenic sources considered resulted an increasing in the spatial peak-temporal average concentrations of pollutants in 3 to 2780 times in relation to those with only biogenic sources. The future scenario showed an increase in the range of 3 to 62 % in average concentrations and 45 to 109 % in peak concentrations depending on the pollutant. In addition, the spatial distributions of the scenarios has shown that the air pollution plume from the city of Manaus is predominantly transported west and southwest, and it can reach hundreds of kilometers in length.

Sensitivity of simulated convection-driven stratosphere-troposphere exchange in WRF-Chem to the choice of physical and chemical parameterization

Science.gov (United States)

Phoenix, Daniel B.; Homeyer, Cameron R.; Barth, Mary C.

2017-08-01

Tropopause-penetrating convection is capable of rapidly transporting air from the lower troposphere to the upper troposphere and lower stratosphere (UTLS), where it can have important impacts on chemistry, the radiative budget, and climate. However, obtaining in situ measurements of convection and convective transport is difficult and such observations are historically rare. Modeling studies, on the other hand, offer the advantage of providing output related to the physical, dynamical, and chemical characteristics of storms and their environments at fine spatial and temporal scales. Since these characteristics of simulated convection depend on the chosen model design, we examine the sensitivity of simulated convective transport to the choice of physical (bulk microphysics or BMP and planetary boundary layer or PBL) and chemical parameterizations in the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). In particular, we simulate multiple cases where in situ observations are available from the recent (2012) Deep Convective Clouds and Chemistry (DC3) experiment. Model output is evaluated using ground-based radar observations of each storm and in situ trace gas observations from two aircraft operated during the DC3 experiment. Model results show measurable sensitivity of the physical characteristics of a storm and the transport of water vapor and additional trace gases into the UTLS to the choice of BMP. The physical characteristics of the storm and transport of insoluble trace gases are largely insensitive to the choice of PBL scheme and chemical mechanism, though several soluble trace gases (e.g., SO2, CH2O, and HNO3) exhibit some measurable sensitivity.

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)

Stan, C.

2009-01-01

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)

Sensitivity of CAM-Chem/DART MOPITT CO Assimilation Performance to the Choice of Ensemble System Configuration: A Case Study for Fires in the Amazon

Science.gov (United States)

Arellano, A. F., Jr.; Tang, W.

2017-12-01

Assimilating observational data of chemical constituents into a modeling system is a powerful approach in assessing changes in atmospheric composition and estimating associated emissions. However, the results of such chemical data assimilation (DA) experiments are largely subject to various key factors such as: a) a priori information, b) error specification and representation, and c) structural biases in the modeling system. Here we investigate the sensitivity of an ensemble-based data assimilation state and emission estimates to these key factors. We focus on investigating the assimilation performance of the Community Earth System Model (CESM)/CAM-Chem with the Data Assimilation Research Testbed (DART) in representing biomass burning plumes in the Amazonia during the 2008 fire season. We conduct the following ensemble DA MOPITT CO experiments: 1) use of monthly-average NCAR's FINN surface fire emissionss, 2) use of daily FINN surface fire emissions, 3) use of daily FINN emissions with climatological injection heights, and 4) use of perturbed FINN emission parameters to represent not only the uncertainties in combustion activity but also in combustion efficiency. We show key diagnostics of assimilation performance for these experiments and verify with available ground-based and aircraft-based measurements.

ChemSearch Journal

African Journals Online (AJOL)

Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. Journal Homepage Image. Chemsearch Journal is a peer – reviewed journal that publishes original research work, scientific papers and technical reports in all the field of Chemistry (pure science, agriculture, environmental science, ...

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.

Benchmarking of AREVA BWR FDIC-PEZOG model against first BFE3 cycle 15 application of On-Line NobleChem results

International Nuclear Information System (INIS)

Pop, M.G.; Lamanna, L.S.; Hoornik, A.; Storey, G.C.; Lemons, J.F.

2015-01-01

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 NobleChem TM 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)

Coupling spectral-bin cloud microphysics with the MOSAIC aerosol model in WRF-Chem: Methodology and results for marine stratocumulus clouds

Science.gov (United States)

Gao, Wenhua; Fan, Jiwen; Easter, R. C.; Yang, Qing; Zhao, Chun; Ghan, Steven J.

2016-09-01

Aerosol-cloud interaction processes can be represented more physically with bin cloud microphysics relative to bulk microphysical parameterizations. However, due to computational power limitations in the past, bin cloud microphysics was often run with very simple aerosol treatments. The purpose of this study is to represent better aerosol-cloud interaction processes in the Chemistry version of Weather Research and Forecast model (WRF-Chem) at convection-permitting scales by coupling spectral-bin cloud microphysics (SBM) with the MOSAIC sectional aerosol model. A flexible interface is built that exchanges cloud and aerosol information between them. The interface contains a new bin aerosol activation approach, which replaces the treatments in the original SBM. It also includes the modified aerosol resuspension and in-cloud wet removal processes with the droplet loss tendencies and precipitation fluxes from SBM. The newly coupled system is evaluated for two marine stratocumulus cases over the Southeast Pacific Ocean with either a simplified aerosol setup or full-chemistry. We compare the aerosol activation process in the newly coupled SBM-MOSAIC against the SBM simulation without chemistry using a simplified aerosol setup, and the results show consistent activation rates. A longer time simulation reinforces that aerosol resuspension through cloud drop evaporation plays an important role in replenishing aerosols and impacts cloud and precipitation in marine stratocumulus clouds. Evaluation of the coupled SBM-MOSAIC with full-chemistry using aircraft measurements suggests that the new model works realistically for the marine stratocumulus clouds, and improves the simulation of cloud microphysical properties compared to a simulation using MOSAIC coupled with the Morrison two-moment microphysics.

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, NO_x, and NO_y 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-NO_x, O₃-CO, and O₃-NO_z 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 NO_x 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

Contributions of foreign, domestic and natural emissions to US ozone estimated using the path-integral method in CAMx nested within GEOS-Chem

Directory of Open Access Journals (Sweden)

A. M. Dunker

2017-10-01

Full Text Available The Goddard Earth Observing System global chemical transport (GEOS-Chem model was used at 2°  ×  2.5° resolution to simulate ozone formation for a base case representing year 2010 and a natural background case without worldwide anthropogenic emissions. These simulations provided boundary concentrations for base and natural background simulations with the Comprehensive Air Quality Model with Extensions (CAMx on a North American domain (one-way nested at 12 km  ×  12 km resolution over March–September 2010. The predicted maximum daily average 8 h (MDA8 background ozone for the US is largest in the mountainous areas of Colorado, New Mexico, Arizona, and California. The background MDA8 ozone in some of these locations exceeds 60 ppb, when averaged over the 10 days with the largest base-case ozone (T10base average. The background ozone generally becomes both a larger fraction of the base-case ozone in the western US and a smaller fraction in the eastern US when proceeding from spring to summer to the T10base average. The ozone difference between the base and background cases represents the increment to ozone from all anthropogenic sources. The path-integral method was applied to allocate this anthropogenic ozone increment to US anthropogenic emissions, Canadian/Mexican anthropogenic emissions, and the anthropogenic components of the lateral and top boundary concentrations (BCs. Using the T10base average MDA8 ozone, the relative importance of the sources is generally US emissions  >  anthropogenic lateral BCs  >  Canadian/Mexican emissions  ≫  anthropogenic top BCs. Specifically, for 10 US urban areas, the source contributions were 12–53 ppb for US emissions, 3–9 ppb for lateral BCs, 0.2–3 ppb for Canadian/Mexican emissions, and  ≤  0.1 ppb for top BCs. The contributions of the lateral BCs are largest for the higher-elevation US sites in the Intermountain West and along the

Application of WRF/Chem-MADRID and WRF/Polyphemus in Europe - Part 1: Model description, evaluation of meteorological predictions, and aerosol-meteorology interactions

Science.gov (United States)

Zhang, Y.; Sartelet, K.; Wu, S.-Y.; Seigneur, C.

2013-07-01

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 terrain and

WRF-Chem simulated surface ozone over south Asia during the pre-monsoon: effects of emission inventories and chemical mechanisms

Directory of Open Access Journals (Sweden)

A. Sharma

2017-12-01

Full Text Available We evaluate numerical simulations of surface ozone mixing ratios over the south Asian region during the pre-monsoon season, employing three different emission inventories in the Weather Research and Forecasting model with Chemistry (WRF-Chem with the second-generation Regional Acid Deposition Model (RADM2 chemical mechanism: the Emissions Database for Global Atmospheric Research – Hemispheric Transport of Air Pollution (EDGAR-HTAP, the Intercontinental Chemical Transport Experiment phase B (INTEX-B and the Southeast Asia Composition, Cloud, Climate Coupling Regional Study (SEAC4RS. Evaluation of diurnal variability in modelled ozone compared to observational data from 15 monitoring stations across south Asia shows the model ability to reproduce the clean, rural and polluted urban conditions over this region. In contrast to the diurnal average, the modelled ozone mixing ratios during noontime, i.e. hours of intense photochemistry (11:30–16:30 IST – Indian Standard Time – UTC +5:30, are found to differ among the three inventories. This suggests that evaluations of the modelled ozone limited to 24 h average are insufficient to assess uncertainties associated with ozone buildup. HTAP generally shows 10–30 ppbv higher noontime ozone mixing ratios than SEAC4RS and INTEX-B, especially over the north-west Indo-Gangetic Plain (IGP, central India and southern India. The HTAP simulation repeated with the alternative Model for Ozone and Related Chemical Tracers (MOZART chemical mechanism showed even more strongly enhanced surface ozone mixing ratios due to vertical mixing of enhanced ozone that has been produced aloft. Our study indicates the need to also evaluate the O3 precursors across a network of stations and the development of high-resolution regional inventories for the anthropogenic emissions over south Asia accounting for year-to-year changes to further reduce uncertainties in modelled ozone over this region.

WRF-Chem simulated surface ozone over south Asia during the pre-monsoon: effects of emission inventories and chemical mechanisms

Science.gov (United States)

Sharma, Amit; Ojha, Narendra; Pozzer, Andrea; Mar, Kathleen A.; Beig, Gufran; Lelieveld, Jos; Gunthe, Sachin S.

2017-12-01

We evaluate numerical simulations of surface ozone mixing ratios over the south Asian region during the pre-monsoon season, employing three different emission inventories in the Weather Research and Forecasting model with Chemistry (WRF-Chem) with the second-generation Regional Acid Deposition Model (RADM2) chemical mechanism: the Emissions Database for Global Atmospheric Research - Hemispheric Transport of Air Pollution (EDGAR-HTAP), the Intercontinental Chemical Transport Experiment phase B (INTEX-B) and the Southeast Asia Composition, Cloud, Climate Coupling Regional Study (SEAC4RS). Evaluation of diurnal variability in modelled ozone compared to observational data from 15 monitoring stations across south Asia shows the model ability to reproduce the clean, rural and polluted urban conditions over this region. In contrast to the diurnal average, the modelled ozone mixing ratios during noontime, i.e. hours of intense photochemistry (11:30-16:30 IST - Indian Standard Time - UTC +5:30), are found to differ among the three inventories. This suggests that evaluations of the modelled ozone limited to 24 h average are insufficient to assess uncertainties associated with ozone buildup. HTAP generally shows 10-30 ppbv higher noontime ozone mixing ratios than SEAC4RS and INTEX-B, especially over the north-west Indo-Gangetic Plain (IGP), central India and southern India. The HTAP simulation repeated with the alternative Model for Ozone and Related Chemical Tracers (MOZART) chemical mechanism showed even more strongly enhanced surface ozone mixing ratios due to vertical mixing of enhanced ozone that has been produced aloft. Our study indicates the need to also evaluate the O3 precursors across a network of stations and the development of high-resolution regional inventories for the anthropogenic emissions over south Asia accounting for year-to-year changes to further reduce uncertainties in modelled ozone over this region.

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

A WRF/Chem sensitivity study using ensemble modelling for a high ozone episode in Slovenia and the Northern Adriatic area

Science.gov (United States)

Žabkar, Rahela; Koračin, Darko; Rakovec, Jože

2013-10-01

A high ozone (O3) concentrations episode during a heat wave event in the Northeastern Mediterranean was investigated using the WRF/Chem model. To understand the major model uncertainties and errors as well as the impacts of model inputs on the model accuracy, an ensemble modelling experiment was conducted. The 51-member ensemble was designed by varying model physics parameterization options (PBL schemes with different surface layer and land-surface modules, and radiation schemes); chemical initial and boundary conditions; anthropogenic and biogenic emission inputs; and model domain setup and resolution. The main impacts of the geographical and emission characteristics of three distinct regions (suburban Mediterranean, continental urban, and continental rural) on the model accuracy and O3 predictions were investigated. In spite of the large ensemble set size, the model generally failed to simulate the extremes; however, as expected from probabilistic forecasting the ensemble spread improved results with respect to extremes compared to the reference run. Noticeable model nighttime overestimations at the Mediterranean and some urban and rural sites can be explained by too strong simulated winds, which reduce the impact of dry deposition and O3 titration in the near surface layers during the nighttime. Another possible explanation could be inaccuracies in the chemical mechanisms, which are suggested also by model insensitivity to variations in the nitrogen oxides (NOx) and volatile organic compounds (VOC) emissions. Major impact factors for underestimations of the daytime O3 maxima at the Mediterranean and some rural sites include overestimation of the PBL depths, a lack of information on forest fires, too strong surface winds, and also possible inaccuracies in biogenic emissions. This numerical experiment with the ensemble runs also provided guidance on an optimum model setup and input data.

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

Science.gov (United States)

Wu, Longtao; Gu, Yu; Jiang, Jonathan H.; Su, Hui; Yu, Nanpeng; Zhao, Chun; Qian, Yun; Zhao, Bin; Liou, Kuo-Nan; Choi, Yong-Sang

2018-04-01

A version of the WRF-Chem model with fully coupled aerosol-meteorology-snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol-radiation interaction (ARI), aerosol-snow interaction (ASI), and aerosol-cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34-42° N, 117-124° W, not including ocean points) are reduced when aerosols are included, therefore reducing large biases in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about -0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about 7 % for precipitation

Ruthenium(II)-catalyzed synthesis of pyrrole- and indole-fused isocoumarins by C-H bond activation in DMF and water

Digital Repository Service at National Institute of Oceanography (India)

Singh, K.S.; Sawant, S.G.; Dixneuf, P.H.

stream_size 26907 stream_content_type text/plain stream_name ChemCatChem_8_1046a.pdf.txt stream_source_info ChemCatChem_8_1046a.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8 Author version...: ChemCatChem, vol.8(6); 2016; 1046-1050 Ruthenium(II) catalysed synthesis of pyrrole and indole fused isocoumarins via C-H bond activation in DMF and water† Keisham S. Singh*,a Sneha G. Sawanta, Pierre H. Dixneuf*,b Abstract: Pyrrole and indole...

Literacy at All Levels. Proceedings of the Annual Study Conference of the United Kingdom Reading Assn. (8th, Manchester, 1971).

Science.gov (United States)

Southgate, Vera, Ed.

Edited versions of selected major papers presented at the July 1971 study conference of the United Kingdom Reading Association, which had the theme "Literacy at All Levels," are included in this book. This group defines literacy as "the mastery of our native language in all its aspects, as a means of communication," and…

Mixed Solvent + Electrolyte

Indian Academy of Sciences (India)

Prof.Biswas

Bagchi B and Biswas R. 1999 Adv. Chem. Phys.109 207. 2. Kashyap H K and Biswas R. 2008 J. Phys. Chem. B112 12431. 3. Kashyap H K and Biswas R. 2010J. Phys. Chem. B114, 254. 4. Kashyap H K and Biswas R. 2010 J. Phys. Chem. B114, 16811. 5. Kashyap H K and Biswas R. 2010 Ind. J. Chem. 49A, 685. 6.

Retrievals of formaldehyde from ground-based FTIR and MAX-DOAS observations at the Jungfraujoch station and comparisons with GEOS-Chem and IMAGES model simulations

Directory of Open Access Journals (Sweden)

B. Franco

2015-04-01

Full Text Available 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.

Mitigating Satellite-Based Fire Sampling Limitations in Deriving Biomass Burning Emission Rates: Application to WRF-Chem Model Over the Northern sub-Saharan African Region

Science.gov (United States)

Wang, Jun; Yue, Yun; Wang, Yi; Ichoku, Charles; Ellison, Luke; Zeng, Jing

2018-01-01

Largely used in several independent estimates of fire emissions, fire products based on MODIS sensors aboard the Terra and Aqua polar-orbiting satellites have a number of inherent limitations, including (a) inability to detect fires below clouds, (b) significant decrease of detection sensitivity at the edge of scan where pixel sizes are much larger than at nadir, and (c) gaps between adjacent swaths in tropical regions. To remedy these limitations, an empirical method is developed here and applied to correct fire emission estimates based on MODIS pixel level fire radiative power measurements and emission coefficients from the Fire Energetics and Emissions Research (FEER) biomass burning emission inventory. The analysis was performed for January 2010 over the northern sub-Saharan African region. Simulations from WRF-Chem model using original and adjusted emissions are compared with the aerosol optical depth (AOD) products from MODIS and AERONET as well as aerosol vertical profile from CALIOP data. The comparison confirmed an 30-50% improvement in the model simulation performance (in terms of correlation, bias, and spatial pattern of AOD with respect to observations) by the adjusted emissions that not only increases the original emission amount by a factor of two but also results in the spatially continuous estimates of instantaneous fire emissions at daily time scales. Such improvement cannot be achieved by simply scaling the original emission across the study domain. Even with this improvement, a factor of two underestimations still exists in the modeled AOD, which is within the current global fire emissions uncertainty envelope.

Sources and characteristics of summertime organic aerosol in the Colorado Front Range: perspective from measurements and WRF-Chem modeling

Directory of Open Access Journals (Sweden)

R. Bahreini

2018-06-01

Full Text Available The evolution of organic aerosols (OAs and their precursors in the boundary layer (BL of the Colorado Front Range during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ, July–August 2014 was analyzed by in situ measurements and chemical transport modeling. Measurements indicated significant production of secondary OA (SOA, with enhancement ratio of OA with respect to carbon monoxide (CO reaching 0.085±0.003 µg m−3 ppbv−1. At background mixing ratios of CO, up to  ∼  1.8 µg m−3 background OA was observed, suggesting significant non-combustion contribution to OA in the Front Range. The mean concentration of OA in plumes with a high influence of oil and natural gas (O&G emissions was  ∼  40 % higher than in urban-influenced plumes. Positive matrix factorization (PMF confirmed a dominant contribution of secondary, oxygenated OA (OOA in the boundary layer instead of fresh, hydrocarbon-like OA (HOA. Combinations of primary OA (POA volatility assumptions, aging of semi-volatile species, and different emission estimates from the O&G sector were used in the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem simulation scenarios. The assumption of semi-volatile POA resulted in greater than a factor of 10 lower POA concentrations compared to PMF-resolved HOA. Including top-down modified O&G emissions resulted in substantially better agreements in modeled ethane, toluene, hydroxyl radical, and ozone compared to measurements in the high-O&G-influenced plumes. By including emissions from the O&G sector using the top-down approach, it was estimated that the O&G sector contributed to  <  5 % of total OA, but up to 38 % of anthropogenic SOA (aSOA in the region. The best agreement between the measured and simulated median OA was achieved by limiting the extent of biogenic hydrocarbon aging and consequently biogenic SOA (bSOA production. Despite a lower production of bSOA in

The Development of Micromachined Gyroscope Structure and Circuitry Technology

Directory of Open Access Journals (Sweden)

Dunzhu Xia

2014-01-01

Full Text Available This review surveys micromachined gyroscope structure and circuitry technology. The principle of micromachined gyroscopes is first introduced. Then, different kinds of MEMS gyroscope structures, materials and fabrication technologies are illustrated. Micromachined gyroscopes are mainly categorized into micromachined vibrating gyroscopes (MVGs, piezoelectric vibrating gyroscopes (PVGs, surface acoustic wave (SAW gyroscopes, bulk acoustic wave (BAW gyroscopes, micromachined electrostatically suspended gyroscopes (MESGs, magnetically suspended gyroscopes (MSGs, micro fiber optic gyroscopes (MFOGs, micro fluid gyroscopes (MFGs, micro atom gyroscopes (MAGs, and special micromachined gyroscopes. Next, the control electronics of micromachined gyroscopes are analyzed. The control circuits are categorized into typical circuitry and special circuitry technologies. The typical circuitry technologies include typical analog circuitry and digital circuitry, while the special circuitry consists of sigma delta, mode matching, temperature/quadrature compensation and novel special technologies. Finally, the characteristics of various typical gyroscopes and their development tendency are discussed and investigated in detail.

The effect of magnetic nanoparticle concentration on the structure organisation of a microferrogel

Science.gov (United States)

Ryzhkov, A. V.; Melenev, P. V.; Balasoiu, M.; Raikher, Yu L.

2018-03-01

Coarse-grained molecular dynamics simulation is applied to study the structural response of micro-sized magnetopolymer objects – microferrogels (MFG). The results for MFGs with different magnetic properties and concentrations of magnetic filler nanoparticles are analysed to detect the transition between non-aggregated configurations and the states with pronounced chains. The nanoparticles are assumed to be either magnetically isotropic or to possess infinite magnetic anisotropy. It is shown that, depending on the type of the particle anisotropy, an applied field in rather different ways affects the MFG structure and shape. Diagrams describing the degree of aggregation as a function of the parameter of the interparticle magnetodipolar interaction and concentration are presented. In particular, it is found that in the case of infinitely anisotropic nanoparticles the aggregation transitions undergoes via a non-trivial scenario. The effect of the structure transformations on the volume change of the MFG objects is studied as well.

Impacts of aerosols on seasonal precipitation and snowpack in California based on convection-permitting WRF-Chem simulations

Energy Technology Data Exchange (ETDEWEB)

Wu, Longtao; Gu, Yu; Jiang, Jonathan; Su, Hui; Yu, Nanpeng; Zhao, Chun; Qian, Yun; Zhao, Bin; Liou, K. N.; Choi, Yong-Sang

2018-04-23

A version of the WRF-Chem model with fully coupled aerosol–meteorology–snowpack is employed to investigate the impacts of various aerosol sources on precipitation and snowpack in California. In particular, the impacts of locally emitted anthropogenic and dust aerosols, and aerosols transported from outside California are studied. We differentiate three pathways of aerosol effects: aerosol–radiation interaction (ARI), aerosol–snow interaction (ASI), and aerosol–cloud interaction (ACI). The convection-permitting model simulations show that precipitation, snow water equivalent (SWE), and surface air temperature averaged over the whole domain (34–42° N, 117–124° W, not including ocean points) are reduced when aerosols are included, therefore reducing large biases in these variables due to the absence of aerosol effects in the model. Aerosols affect California water resources through the warming of mountaintops and the reduction of precipitation; however, different aerosol sources play different roles in changing surface temperature, precipitation, and snowpack in California by means of various weights of the three pathways. ARI by all aerosols mainly cools the surface, leading to slightly increased SWE over the mountains. Locally emitted dust aerosols warm the surface of mountaintops through ASI, in which the reduced snow albedo associated with dusty snow leads to more surface absorption of solar radiation and reduced SWE. Transported aerosols and local anthropogenic aerosols play a dominant role in increasing nonprecipitating clouds but reducing precipitation through ACI, leading to reduced SWE and runoff on the Sierra Nevada, as well as the warming of mountaintops associated with decreased SWE and hence lower surface albedo. The average changes in surface temperature from October 2012 to June 2013 are about −0.19 and 0.22 K for the whole domain and over mountaintops, respectively. Overall, the averaged reduction during October to June is about

Air quality modelling in the summer over the eastern Mediterranean using WRF-Chem: chemistry and aerosol mechanism intercomparison

Science.gov (United States)

Georgiou, George K.; Christoudias, Theodoros; Proestos, Yiannis; Kushta, Jonilda; Hadjinicolaou, Panos; Lelieveld, Jos

2018-02-01

We employ the WRF-Chem model to study summertime air pollution, the intense photochemical activity and their impact on air quality over the eastern Mediterranean. We utilize three nested domains with horizontal resolutions of 80, 16 and 4 km, with the finest grid focusing on the island of Cyprus, where the CYPHEX campaign took place in July 2014. Anthropogenic emissions are based on the EDGAR HTAP global emission inventory, while dust and biogenic emissions are calculated online. Three simulations utilizing the CBMZ-MOSAIC, MOZART-MOSAIC, and RADM2-MADE/SORGAM gas-phase and aerosol mechanisms are performed. The results are compared with measurements from a dense observational network of 14 ground stations in Cyprus. The model simulates T2 m, Psurf, and WD10 m accurately, with minor differences in WS10 m between model and observations at coastal and mountainous stations attributed to limitations in the representation of the complex topography in the model. It is shown that the south-eastern part of Cyprus is mostly affected by emissions from within the island, under the dominant (60 %) westerly flow during summertime. Clean maritime air from the Mediterranean can reduce concentrations of local air pollutants over the region during westerlies. Ozone concentrations are overestimated by all three mechanisms (9 % ≤ NMB ≤ 23 %) with the smaller mean bias (4.25 ppbV) obtained by the RADM2-MADE/SORGAM mechanism. Differences in ozone concentrations can be attributed to the VOC treatment by the three mechanisms. The diurnal variability of pollution and ozone precursors is not captured (hourly correlation coefficients for O3 ≤ 0.29). This might be attributed to the underestimation of NOx concentrations by local emissions by up to 50 %. For the fine particulate matter (PM2.5), the lowest mean bias (9 µg m-3) is obtained with the RADM2-MADE/SORGAM mechanism, with overestimates in sulfate and ammonium aerosols. Overestimation of sulfate aerosols by this mechanism may be

Antimicrobial activity and bioguided fractionation of Rumex tingitanus extracts for meat preservation.

Science.gov (United States)

Mhalla, Dhekra; Bouaziz, Amira; Ennouri, Karim; Chawech, Rachid; Smaoui, Slim; Jarraya, Raoudha; Tounsi, Slim; Trigui, Mohamed

2017-03-01

This study was undertaken to investigate the antibacterial and antifungal activities of Rumex tingitanus leaves extracts as well as the identification of bioactive components and their performance in meat preservation. Total phenolics and flavonoids showed the highest content of phenolics and flavonoids in the ethyl acetate fraction (Rt EtOAcF). For antimicrobial efficacy, leaves extract and derived fraction were tested for their capacity to inhibit bacterial and fungal proliferation in vitro and in vivo. The ethyl acetate fraction showed the most potent antibacterial and antifungal activities compared to the others extracts. Thus, the efficacy of this extract to inhibit the proliferation of Listeria monocytogenes in minced beef meat model was examined. This fraction eradicates the L. monocytogenes population in meat in a concentration- and time-dependent manner. A bio-guided purification of the Rt EtOAc fraction resulted in the isolation of the compound responsible for the observed antimicrobial activity. This compound was identified as luteolin by analysis of spectroscopic data. Luteolin (PubChem CID: 5280445); p-iodonitrotetrazolium chloride (PubChem CID: 64957); Amphotericin B (PubChem CID: 5280965); Gentamicin and (PubChem CID: 6419933); Hexane (PubChem CID: 8058); Methanol (PubChem CID: 887); Ethanol (PubChem CID: 702); Dimethylsulfoxide (PubChem CID: 679); Quercetin (PubChem CID: 5280343); Gallic acid (PubChem CID: 370). Copyright © 2016 Elsevier Ltd. All rights reserved.

Heats of Vaporization of Room Temperature Ionic Liquids by Tunable Vacuum Ultraviolet Photoionization

Science.gov (United States)

2009-12-07

18) Emel’yanenko, V. N.; Verevkin, S. P.; Heintz, A.; Corfield, J.-A.; deyko, A.; Lovelock , K. R. J.; Licence, P.; Jones, R. G. J. Phys. Chem. B 2008...112, 11734. (19) Armstrong, J. P.; Hurst, C.; Jones, R. G.; Licence, P.; Lovelock , K. R. J.; Satterly, C. J.; Villar-Garcia, I. J. Phys. Chem. Chem...Phys. 2007, 9, 982. (20) Lovelock , K. R. J.; Deyko, A.; Corfield, J.-A.; Gooden, P. N.; Licence, P.; Jones, R. G. ChemPhysChem 2009, 10, 337. (21

The effect of prefermentative addition of gallic acid and ellagic acid on the red wine color, copigmentation and phenolic profiles during wine aging.

Science.gov (United States)

Zhang, Xin-Ke; He, Fei; Zhang, Bo; Reeves, Malcolm J; Liu, Yue; Zhao, Xu; Duan, Chang-Qing

2018-04-01

Though non-anthocyanin phenolics normally do not have red color, they affect the red color expression in the copigmentation of red wines. In this study, the influence of prefermentative addition of 300mg/L gallic acid and ellagic acid, as cofactors, on aging dry red wines had been systematically evaluated at the industrial scales from the perspectives of color, phenolic profiles and copigmentation effects of anthocyanins. Red wines made with these two compounds exhibited better color properties than the control, having better CIELAB chromatic parameters. Additionally, significantly higher levels of detectable anthocyanins and copigmented anthocyanin ratio had been observed. Wines with ellagic acid showed better chromatic properties and phenolic profiles than wines with gallic acid, as shown in previous theoretical results. Anti-copigmentation phenomenon was noticed and elucidated. These practical results confirmed that ellagic acid was the better cofactor, and would give more additional guidance for the production of high quality wine. Malvidin-3-O-glucoside (PubChem CID: 443,652); Petunidin-3-O-glucoside (PubChem CID: 443,651); Delphinidin-3-O-glucoside (PubChem CID: 443,650); Peonidin-3-O-glucoside (PubChem CID: 443,654); Ellagic acid (PubChem CID: 5,281,855); Gallic acid (PubChem CID: 370); Quercetin (PubChem CID: 443,654); Caffeic acid (PubChem CID: 689,043); (+)-catechin (PubChem CID: 9064); Vanillic acid (PubChem CID: 8468). Copyright © 2017. Published by Elsevier Ltd.

Ozone data assimilation with GEOS-Chem: a comparison between 3-D-Var, 4-D-Var, and suboptimal Kalman filter approaches

Science.gov (United States)

Singh, K.; Sandu, A.; Bowman, K. W.; Parrington, M.; Jones, D. B. A.; Lee, M.

2011-08-01

Chemistry transport models determine the evolving chemical state of the atmosphere by solving the fundamental equations that govern physical and chemical transformations subject to initial conditions of the atmospheric state and surface boundary conditions, e.g., surface emissions. The development of data assimilation techniques synthesize model predictions with measurements in a rigorous mathematical framework that provides observational constraints on these conditions. Two families of data assimilation methods are currently widely used: variational and Kalman filter (KF). The variational approach is based on control theory and formulates data assimilation as a minimization problem of a cost functional that measures the model-observations mismatch. The Kalman filter approach is rooted in statistical estimation theory and provides the analysis covariance together with the best state estimate. Suboptimal Kalman filters employ different approximations of the covariances in order to make the computations feasible with large models. Each family of methods has both merits and drawbacks. This paper compares several data assimilation methods used for global chemical data assimilation. Specifically, we evaluate data assimilation approaches for improving estimates of the summertime global tropospheric ozone distribution in August 2006 based on ozone observations from the NASA Tropospheric Emission Spectrometer and the GEOS-Chem chemistry transport model. The resulting analyses are compared against independent ozonesonde measurements to assess the effectiveness of each assimilation method. All assimilation methods provide notable improvements over the free model simulations, which differ from the ozonesonde measurements by about 20 % (below 200 hPa). Four dimensional variational data assimilation with window lengths between five days and two weeks is the most accurate method, with mean differences between analysis profiles and ozonesonde measurements of 1-5 %. Two sequential

Application of WRF/Chem-MADRID and WRF/Polyphemus in Europe - Part 1: Model description and evaluation of meteorological predictions

Science.gov (United States)

Zhang, Y.; Sartelet, K.; Wu, S.-Y.; Seigneur, C.

2013-02-01

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, as well as 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°. Six simulated meteorological variables (i.e. 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. WRF demonstrates its capability in capturing diurnal/seasonal variations and spatial gradients of major meteorological variables. While the domainwide performance of T2, Q2, RH2, and WD10 at all three grid resolutions is satisfactory overall, large positive or negative biases occur in WS10 and Precip even at 0.025°. 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 terrain and subgrid-scale meteorological phenomena, due to inaccuracies in model initialization parameterization (e.g. lack of soil temperature and moisture nudging), limitations in the physical parameterizations of the planetary boundary layer (e.g. cloud microphysics, cumulus parameterizations, and ice nucleation treatments) as well as limitations in surface heat and moisture budget

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

2009-02-01

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 precipitation and 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 PM_2.5 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

Fluorine effect on pericyclic and pseudopericyclic processes ...

Indian Academy of Sciences (India)

Administrator

Glendening E D, Reed A E, Carpenter J E and Wein- hold F 1988 NBO 3.1 Program Manual. 39. Fukui K 1981 Acc. Chem. Res. 14 363. 40. Gonzalez C and Schlegel H B 1989 J. Chem. Phys. 90 2154. 41. Gonzalez C and Schlegel H B 1990 J. Phys. Chem. 94 5223. 42. Wolinski K, Hilton J F and Pulay P 1990 J. Am. Chem.

Palladium complexes of pyrrole-2-aldehyde thiosemicarbazone ...

Indian Academy of Sciences (India)

Chem. Rev. 253 1384; (j) Lobana T S, Sharma. R, Bawa G and Khanna S 2009 Coord. Chem. Rev. 253. 977; (k) Quiroga A G and Ranninger C N 2004 Coord. Chem. Rev. 248 119; (l) Dilworth J R, Arnold P, Morales. D, Wong Y L and Zheng Y 2002 Modern Coord. Chem. 217; (m) West D X, Liberta A E, Padhye S B, Chikate.

Chemical Reactions of Metal-Metal Bonded Compounds of the Transition Elements.

Science.gov (United States)

1981-05-18

F.A. Cotton, N.W. Extine and R.L. Kelly, J. Am. Chem. Soc., 100, 2256 (1978). 98 35. Idem, ibid, 101, 7645 (1979). 36. G.B. Ansell and L. Katz, Acta...Muetterties, J. Am. Chem. Soc., 100, 4107 (1978). 102. R.D. Adams , D.E. Collins and F.A. Cotton, J. Am. Chem. Soc., 96, 749 (1974). 103. D.G. DeWit, J.P... Adams , D.M. Collins and F.A. Cotton, Inorg. Chem., 13, 1086 (1974). 152. M.D. Curtis, K.R. Han and W.M. Butler, Inorg. Chem., 19, 2096 (1980). 153. W.I

ChemSearch Journal: Editorial Policies

African Journals Online (AJOL)

A. A. Audu (Analytical Chemistry) Department of Pure and Industrial Chemistry, Bayero University, P.M.B. 3011, Kano, Nigeria. Prof. S. M. Gumel (Colour & Polymer Chemistry) Department of Pure and Industrial Chemistry, Bayero University, P.M.B. 3011, Kano, Nigeria. Prof. S. Y. Mudi (Organic Chemistry) Department of ...

Inverse modeling and mapping US air quality influences of inorganic PM2.5 precursor emissions using the adjoint of GEOS-Chem

Science.gov (United States)

Henze, D. K.; Seinfeld, J. H.; Shindell, D. T.

2009-08-01

Influences of specific sources of inorganic PM2.5 on peak and ambient aerosol concentrations in the US are evaluated using a combination of inverse modeling and sensitivity analysis. First, sulfate and nitrate aerosol measurements from the IMPROVE network are assimilated using the four-dimensional variational (4D-Var) method into the GEOS-Chem chemical transport model in order to constrain emissions estimates in four separate month-long inversions (one per season). Of the precursor emissions, these observations primarily constrain ammonia (NH3). While the net result is a decrease in estimated US~NH3 emissions relative to the original inventory, there is considerable variability in adjustments made to NH3 emissions in different locations, seasons and source sectors, such as focused decreases in the midwest during July, broad decreases throughout the US~in January, increases in eastern coastal areas in April, and an effective redistribution of emissions from natural to anthropogenic sources. Implementing these constrained emissions, the adjoint model is applied to quantify the influences of emissions on representative PM2.5 air quality metrics within the US. The resulting sensitivity maps display a wide range of spatial, sectoral and seasonal variability in the susceptibility of the air quality metrics to absolute emissions changes and the effectiveness of incremental emissions controls of specific source sectors. NH3 emissions near sources of sulfur oxides (SOx) are estimated to most influence peak inorganic PM2.5 levels in the East; thus, the most effective controls of NH3 emissions are often disjoint from locations of peak NH3 emissions. Controls of emissions from industrial sectors of SOx and NOx are estimated to be more effective than surface emissions, and changes to NH3 emissions in regions dominated by natural sources are disproportionately more effective than regions dominated by anthropogenic sources. NOx controls are most effective in northern states in

SOFG: Standards requirements

International Nuclear Information System (INIS)

Gerganov, T.; Grigorov, S.; Kozhukharov, V.; Brashkova, N.

2005-01-01

It is well-known that Solid Oxide Fuel Cells will have industrial application in the nearest future. In this context, the problem of SOFC materials and SOFC systems standardization is of high level of priority. In the present study the attention is focused on the methods for physical and chemical characterization of the materials for SOFC components fabrication and about requirements on single SOFC cells tests. The status of the CEN, ISO, ASTM (ANSI, ASSN) and JIS class of standards has been verified. Standards regarding the test methods for physical-chemical characterization of vitreous materials (as sealing SOFC component), ceramic materials (as electrodes and electrolyte components, including alternative materials used) and metallic materials (interconnect components) are subject of overview. It is established that electrical, mechanical, surface and interfacial phenomena, chemical durability and thermal corrosion behaviour are the key areas for standardization of the materials for SOFC components

Crisis management: Planning for the inevitable

Directory of Open Access Journals (Sweden)

Niyaz Aboudzadeh

2014-06-01

Full Text Available The aim of this study is to identify important factors influencing organizational readiness to deal with the crisis in business organizations. The study designs a questionnaire in Likert scale and distributes it among some experts who work for Mapna company in Iran. The study uses the method developed by Mitroff (2005 [Mitroff, I. I. (2005. Why some companies emerge stronger and better from a crisis: 7 essential lessons for surviving disaster. AMACOM Div American Mgmt Assn.], which investigates the effects of four factors including job satisfaction, increase in income, cost reduction and change in strategies on crisis management. Using Pearson correlation ratio, the study has confirmed a positive and meaningful relationship between crisis management and three factors including increase in income, cost reduction and change in strategies. However, the study did not find any evidence to support the relationship between job satisfaction and crisis management.

WRF-Chem model simulations of a dust outbreak over the central Mediterranean and comparison with multi-sensor desert dust observations

Science.gov (United States)

Rizza, Umberto; Barnaba, Francesca; Marcello Miglietta, Mario; Mangia, Cristina; Di Liberto, Luca; Dionisi, Davide; Costabile, Francesca; Grasso, Fabio; Gobbi, Gian Paolo

2017-01-01

In this study, the Weather Research and Forecasting model with online coupled chemistry (WRF-Chem) is applied to simulate an intense Saharan dust outbreak event that took place over the Mediterranean in May 2014. Comparison of a simulation using a physics-based desert dust emission scheme with a numerical experiment using a simplified (minimal) emission scheme is included to highlight the advantages of the former. The model was found to reproduce well the synoptic meteorological conditions driving the dust outbreak: an omega-like pressure configuration associated with a cyclogenesis in the Atlantic coasts of Spain. The model performances in reproducing the atmospheric desert dust load were evaluated using a multi-platform observational dataset of aerosol and desert dust properties, including optical properties from satellite and ground-based sun photometers and lidars, plus in situ particulate matter mass concentration (PM) data. This comparison allowed us to investigate the model ability in reproducing both the horizontal and the vertical displacement of the dust plume, as well as its evolution in time. The comparison with satellite (MODIS-Terra) and sun photometers (AERONET) showed that the model is able to reproduce well the horizontal field of the aerosol optical depth (AOD) and its evolution in time (temporal correlation coefficient with AERONET of 0.85). On the vertical scale, the comparison with lidar data at a single site (Rome, Italy) confirms that the desert dust advection occurs in several, superimposed "pulses" as simulated by the model. Cross-analysis of the modeled AOD and desert dust emission fluxes further allowed for the source regions of the observed plumes to be inferred. The vertical displacement of the modeled dust plume was in rather good agreement with the lidar soundings, with correlation coefficients among aerosol extinction profiles up to 1 and mean discrepancy of about 50 %. The model-measurement comparison for PM10 and PM2.5 showed a

Molecular and functional roles of 6C CC chemokine 19 in defense system of striped murrel Channa striatus.

Science.gov (United States)

Arockiaraj, Jesu; Bhatt, Prasanth; Harikrishnan, Ramasamy; Arasu, Mariadhas Valan; Al-Dhabi, Naif Abdullah

2015-08-01

In this study, we have reported the molecular information of chemokine-19 (Chem19) from striped murrel Channa striatus (Cs). CsCC-Chem19 cDNA sequence was 555 base pair (bp) in length which is 68bp 5' untranslated region (UTR), 339bp translated region and 149bp 3' UTR. The translated region is encoded for a polypeptide of 112 amino acids. CsCC-Chem19 peptide contains a signal sequence between 1 and 26 and an interleukin (IL) 8 like domain between 24 and 89. The multiple sequence alignment showed a 'DCCL' motif, an indispensable motif present in all CC chemokines which was conserved throughout the evolution. Phylogenetic tree showed that CsCC-Chem19 formed a cluster with chemokine 19 from fishes. Secondary structure of CsCC-Chem19 revealed that the peptide contains maximum amount of coils (61.6%) compared to α-helices (25.9%%) and β-sheet (12.5%). Further, 3D analysis indicated that the cysteine residues at 33, 34, 59 and 75 making the disulfide bridges as 33 = 59 and 34 = 75. Significantly (P coding region of CsCC-Chem19, recombinant CsCC-Chem19 protein was produced. The recombinant CsCC-Chem19 protein induced the cellular proliferation and respiratory burst activity of C. striatus peripheral blood leukocytes (PBL) in a concentration dependent manner. Moreover, the chemotactic activity showed that the recombinant CsCC-Chem19 significantly (P < 0.05) enhanced the movement of PBL of C. striatus. Conclusively, CsCC-Chem19 is a 6C CC chemokine having an ability to perform both inflammatory and homeostatic functions. However, further research is necessary to understand the potential of 6C CC chemokine 19 of C. striatus, particularly their regulatory ability on different cellular components in the defense system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microwave irradiation - a closer look at heating efficiencies

NARCIS (Netherlands)

Hoogenboom, R.; Wilms, T.F.A.; Schubert, U.S.

2008-01-01

Microwave irradn. is rapidly evolving into a common heat source in different areas of chem. including medicinal and org. chem. as well as polymer chem. The major advantages of the use of microwave irradn. are the often obsd. faster and cleaner reactions and sometimes changes in selectivity. Although

Understanding the Relative Contributions of and Critical Enzymes for the Three Pathways for Intracrine Metabolism of Testicular Androgens in Advanced Prostate Cancer

Science.gov (United States)

2017-10-01

Peroxisomal Enzymes: Cytisine-linked Isoflavonoids as Inhibitors of Hydroxysteroid 17-beta-dehydrogenase-4 (HSD17B4) Journal: Org Biomol Chem Volume...J. Chem. 2010, 88, 1233–1239; c) R. A. Valiulin, T. M. Arisco, A. G. Kutateladze, J. Org . Chem. 2011, 76, 1319–1332; d) P. J. Cremins, S. T...Saengchantara, T. W. Wallace, Tetrahedron 1987, 43, 3075–3082; e) R. P. Hsung, J. Org . Chem. 1997, 62, 7904–7905. [11] a) M. Von Strandtmann, M. P. Cohen, J

Supersonic Jet Studies of Benzyl Alcohols: Minimum Energy Conformations and Torsional Motion

Science.gov (United States)

1990-05-13

New York: 1980. (46) Bernstein, E. R.; Law, K.; Schauer, M. J. Chem. Phys. 1984, 80, 207. (47) Hanzlik , R. P.; Schaefer , A. R.; Moon , J. B.; Judson , C...M. J. Am. Chem. Soc. 1987 , 109 , 4926 . -32- Table I. Conformations of substituted benzenes as established by laser jet spectroscopy. jY x 1 ortho T...Chem. Soc. 1987 , 109 , 3453. -29- (11) Breen, P. J.; Bernstein, E. R.; Seeman, J. I. J. Chem, Phys. 1987 , 87, 3269. (12) Breen, P. J.; Warren, J. A

Effects of biomass smoke from southern Africa on stratocumulus over southeastern Atlantic Ocean based on satellite observations and WRF-Chem model simulations

Science.gov (United States)

Lu, Z.; Liu, X.; Zhang, Z.; Zhao, C.; Meyer, K.; Rajapakshe, C.; Wu, C.; Yang, Z.; Penner, J.

2017-12-01

Each year, large amount of biomass burning (BB) aerosols are emitted over southern Africa, and transported by the predominant circulation to the southeastern Atlantic Ocean (SEA), where they overly and potentially interact with the semi-permanent stratocumulus deck in the marine boundary layer (MBL). Many previous studies suggested that the aerosol plumes are well separated from the MBL clouds, and only focused on the radiative effects of BB aerosols (direct + semi-direct radiative effects); however, as shown in several recent satellite observational studies, BB aerosols are able to be frequently entrained into the underlying clouds, function as cloud condensation nuclei (CCN), and potentially cause microphysical effects. Based on satellite observations from CATS, we found that the mixing frequencies between above-cloud aerosols and MBL clouds are very high ( 50%) over both coastal and remote regions, suggesting that BB aerosols may likely contact MBL cloud top and function as CCN quickly after they are transported over SEA. Despite the potential importance of the microphysical effect of BB aerosols over SEA, its magnitude is not fully assessed by modeling studies. In this study, we employ WRF-Chem model to study the impacts of BB aerosols on MBL stratocumulus clouds over SEA during the fire season of 2014. By designing three cases, we are able to quantitatively determine the relative importance of microphysical and radiative effects of BB aerosols. Our modeling results show that, by serving as CCN, BB aerosols are able to alter cloud properties of stratocumulus (e.g. higher cloud droplet number concentration [CDNC], higher cloud liquid water path [LWP], and larger cloud fraction [CF] before noon) and exert significant cooling effect at TOA (-8.05 Wm-2) over SEA. The cooling is primarily caused by higher CDNC (the Twomey effect), and secondarily by the changes in LWP and CF (the cloud lifetime effect). The semi-direct effect estimated in this study is smaller in

Chemical Technology Division progress report, October 1, 1989--June 30, 1991

Energy Technology Data Exchange (ETDEWEB)

1992-04-01

This progress report reviews the mission of the Chemical Technology Division (Chem Tech) and presents a summary of organizational structure, programmatic sponsors, and funding levels for the period October 1, 1988, through June 30, 1991. The report also summarizes the missions and activities of organizations within Chem Tech for the reporting period. Specific projects performed within Chem Tech`s energy research programs, waste and environmental programs, and radiochemical processing programs are highlighted. Other information regarding publications, patents, awards, and conferences organized by Chem Tech staff is also included.

Chemical Technology Division progress report, October 1, 1989--June 30, 1991

Energy Technology Data Exchange (ETDEWEB)

1992-04-01

This progress report reviews the mission of the Chemical Technology Division (Chem Tech) and presents a summary of organizational structure, programmatic sponsors, and funding levels for the period October 1, 1988, through June 30, 1991. The report also summarizes the missions and activities of organizations within Chem Tech for the reporting period. Specific projects performed within Chem Tech's energy research programs, waste and environmental programs, and radiochemical processing programs are highlighted. Other information regarding publications, patents, awards, and conferences organized by Chem Tech staff is also included.

On the equivalence of LIST and DIIS methods for convergence acceleration

Energy Technology Data Exchange (ETDEWEB)

Garza, Alejandro J. [Department of Chemistry, Rice University, Houston, Texas 77251-1892 (United States); Scuseria, Gustavo E. [Department of Chemistry and Department of Physics and Astronomy, Rice University, Houston, Texas 77251-1892, USA and Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

2015-04-28

Self-consistent field extrapolation methods play a pivotal role in quantum chemistry and electronic structure theory. We, here, demonstrate the mathematical equivalence between the recently proposed family of LIST methods [Wang et al., J. Chem. Phys. 134, 241103 (2011); Y. K. Chen and Y. A. Wang, J. Chem. Theory Comput. 7, 3045 (2011)] and the general form of Pulay’s DIIS [Chem. Phys. Lett. 73, 393 (1980); J. Comput. Chem. 3, 556 (1982)] with specific error vectors. Our results also explain the differences in performance among the various LIST methods.

Application of Weather Research and Forecasting Model with Chemistry (WRF/Chem) over northern China: Sensitivity study, comparative evaluation, and policy implications

Science.gov (United States)

Wang, Litao; Zhang, Yang; Wang, Kai; Zheng, Bo; Zhang, Qiang; Wei, Wei

2016-01-01

An extremely severe and persistent haze event occurred over the middle and eastern China in January 2013, with the record-breaking high concentrations of fine particulate matter (PM2.5). In this study, an online-coupled meteorology-air quality model, the Weather Research and Forecasting Model with Chemistry (WRF/Chem), is applied to simulate this pollution episode over East Asia and northern China at 36- and 12-km grid resolutions. A number of simulations are conducted to examine the sensitivities of the model predictions to various physical schemes. The results show that all simulations give similar predictions for temperature, wind speed, wind direction, and humidity, but large variations exist in the prediction for precipitation. The concentrations of PM2.5, particulate matter with aerodynamic diameter of 10 μm or less (PM10), sulfur dioxide (SO2), and nitrogen dioxide (NO2) are overpredicted partially due to the lack of wet scavenging by the chemistry-aerosol option with the 1999 version of the Statewide Air Pollution Research Center (SAPRC-99) mechanism with the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) and the Volatility Basis Set (VBS) for secondary organic aerosol formation. The optimal set of configurations with the best performance is the simulation with the Gorddard shortwave and RRTM longwave radiation schemes, the Purdue Lin microphysics scheme, the Kain-Fritsch cumulus scheme, and a nudging coefficient of 1 × 10-5 for water vapor mixing ratio. The emission sensitivity simulations show that the PM2.5 concentrations are most sensitive to nitrogen oxide (NOx) and SO2 emissions in northern China, but to NOx and ammonia (NH3) emissions in southern China. 30% NOx emission reductions may result in an increase in PM2.5 concentrations in northern China because of the NH3-rich and volatile organic compound (VOC) limited conditions over this area. VOC emission reductions will lead to a decrease in PM2.5 concentrations in eastern China

Origin of ultra-low thermal conductivity in complex chalcogenides ...

Indian Academy of Sciences (India)

Kanishka Biswas

Chem. A 2015, 3, 648. Banik et al. Chem. Mater., 2015, 27, 581. Guin et al. J. Mater. Chem. .... Thermal conductivity of SnTe. 13. 300 400 500 600 700. 0. 1. 2. 3. SnTe κ lat. (W. /mK). T (K) κ min .... (b) part-crystalline part-liquid state,. (c) rattling ...

Nitrous Acid as an Oxidant in Acidic Media

Science.gov (United States)

1979-09-25

current work is the account of Ogsts and Sawski3 who studied the oxidation of benzyl ethers at 90C in acidic, aqueous dioxane. They found an increase in...and G. Tobin, Chem. Com., 180 (1978); (b) J. Hoggett , R. Moodie, and K. Schofield, Chem. Comm., 605 (1969). 15. (a) B. Challis and A. Lawson. J. Chem

Untitled

African Journals Online (AJOL)

Ley, S.V.; Woodward, P.R. Tetrahedron Letters 1987, 28, 345. 9. Labelled reagents were bought from Aldrich Chemical Company. 10. Davidson, D.; Bernhard, S.A. J. Am. Chem. Soc. 1948, 70, 3426; Philhaja, K.; Sielo,. M. Acta Chem. Scand. 1968, 22, 3053. 11. Baig, M.V.A.; Owen, L.N. J. Chem. Soc. /C 1966, 540: Neises, ...

A triad of rhenium-mediated transformations

Indian Academy of Sciences (India)

Unknown

Gangopadhyay J, Sengupta S, Bhattacharyya S, Chakraborty I and Chakravorty A 2002 Inorg. Chem. 41 2616. 9. Geldard J F and Lions F 1965 J. Org. Chem. 30 318. 10. Kliegman J M and Barnes R K 1970 Tetrahedron 26 2555. 11. Bhattacharyya S, Chakraborty I, Dirghangi B K and Chakravorty A 2001 Inorg. Chem.40286.

Chemical Technology Division progress report, July 1, 1991--December 31, 1992

International Nuclear Information System (INIS)

Genung, R.K.; Hightower, J.R.; Bell, J.T.

1993-05-01

This progress report reviews the mission of the Chemical Technology Division (Chem Tech) and presents a summary of organizational structure, programmatic sponsors, and funding levels for the period July 1, 1991, through December 31, 1992. The report also summarizes the missions and activities of organizations within Chem Tech for the reporting period. Specific projects performed within Chem Tech's energy research programs, waste and environmental programs, and radiochemical processing programs are highlighted. Special programmatic activities conducted by the division are identified and described. Other information regarding publications, patents, awards, and conferences organized by Chem Tech staff is also included

Anthropogenic and volcanic emission impacts on SO2 dynamics and acid rain profiles. Numerical study using WRF-Chem in a high-resolution modeling

Science.gov (United States)

Vela, A. V.; González, C. M.; Ynoue, R.; Rojas, N. Y.; Aristizábal, B. H.; Wahl, M.

2017-12-01

Eulerian 3-D chemistry transport models (CTM) have been widely used for the study of air quality in urban environments, becoming an essential tool for studying the impacts and dynamics of gases and aerosols on air quality. However, their use in Colombia is scarce, especially in medium-sized cities, which are experimenting a fast urban growth, increasing the risk associated with possible air pollution episodes. In the densely populated medium-sized Andean city of Manizales, Colombia - a city located on the western slopes of the central range of the Andes (urban population 368000; 2150 m.a.s.l), there is an influence of the active Nevado del Ruiz volcano, located 28 km to the southwest. This natural source emits daily gas and particle fluxes, which could influence the atmospheric chemistry of the city and neighboring towns. Hence, the zone presents a unique combination of anthropogenic and volcanic sulfur gas emissions, which affects SO2 dynamics in the urban area, influencing also in the formation of acid rain phenomenon in the city. Therefore, studies analyzing the relative contribution of anthropogenic and volcanic emission could contribute with a deep understanding about causes and dynamics of both acid rain phenomenon and ambient SO2 levels in Manizales. This work aimed to analyze the influence of anthropogenic (on-road vehicular and industrial point-sources) and volcanic sulfur emissions in SO2 atmospheric chemistry dynamics, evaluating its possible effects on acid rain profiles. Ambient SO2 levels and day-night rain samples were measured and used to analyze results obtained from the application of the fully-coupled on-line WRF-Chem model. Two high-resolution simulations were performed during two dry and wet one-week periods in 2015. Analysis of SO2 dispersion patterns and comparison with SO2 observations in the urban area were performed for three different scenarios in which natural and anthropogenic emissions were simulated separately. Results suggest that

A theoretical study of porphyrin isomers and their core-modified ...

Indian Academy of Sciences (India)

Unknown

Harmjanz M, Gill H S and Scott M J 2000 J. Am. Chem. Soc. 122 10476; Anzenbacher P Jr, Jursikova. K and Sessler J L 2000 J. Am. Chem. Soc. 122 9350;. Gisselbrecht J P, Gross M, Vogel E and Sessler J L. 2000 Inorg. Chem. 39 2850; Anand V G, Pushpan S. K, Venkatraman S, Narayanan S J, Dey A,. Chandrashekar ...

Generation of nitryl chloride from chlorotrimethylsilane-acetyl nitrate ...

Indian Academy of Sciences (India)

Administrator

1 1113. 31. Mohammed A H A 2003 Ph D thesis, Bangalore Uni- versity. 32. (a) Kresze G, Mayer N M and Winkler J 1971 Liebigs. Ann. Chem. 747 172; (b) Bosch T, Kresze G and. Winkler J 1975 Liebigs Ann. Chem. 1009; (c). Tordeux M, Boumizane K and Wakselman C 1995. J. Fluorine Chem. 70 207; (d) Muller E, Fries D.

Ultraviolet Photoionization Efficiency of the Vaporized Ionic Liquid 1-Butyl-3-Methylimidazolium Tricyanomethanide: Direct Detection of the Intact Ion Pair (Post Print)

Science.gov (United States)

2012-09-21

Lovelock , K. R. J.; Satterly, C. J.; Villar-Garcia, I. J. Phys. Chem. Chem. Phys. 2007, 9, 982−990. (11) Strasser, D.; Goulay, F.; Kelkar, M. S.; Maginn, E...J.; Leone, S. R. J. Phys. Chem. A 2007, 111, 3191−3915. (12) Lovelock , K. R. J.; Deyko, A.; Corfield, J.-A.; Gooden, P. N.; Licence, P.; Jones, R. G

Bull.Chem.Soc.Ethiop.,4(1)

African Journals Online (AJOL)

axial coordination of halides stabilizes the copper(III) state of copper macrocyclic complexes. ... employed and tetraethylammonium perchlorate, or reagent grade acids were used as supporting electrolytes. RESULTS AND .... Summary of kinetic parameters for acid dependent Fe(phen)3+ oxidetions of b-diimine complexes.

ChemWaste appeals Hanford permit stance

International Nuclear Information System (INIS)

Anon.

1993-01-01

Chemical Waste Management, Inc. is appealing the Washington State Department of Ecology's decision to suspend its review of the company's proposal to build a hazardous waste incinerator and two mixed waste incinerators at the Hanford Nuclear Site near Richland, Washington. The company wants to build the incinerators on a 200 acre parcel in the DOE reservation that is leased to the State. The State contends the two mixed waste incinerators meet siting criteria, but the hazardous waste unit does not. A compromise may be reached between DOE and Washington state involving the transfer of title to the leased land from DOE to the State

Synthesis and characterization of Ruddlesden–Popper (RP) type ...

Indian Academy of Sciences (India)

Administrator

Bendersky L A, Greenblatt M and Chen R 2003. J. Solid State Chem. 174 418. 3. Zhang Z, Greenblatt M and Goodenough J B 1994. J. Solid State Chem. 108 402. 4. Sreedhar K, McElfresh M, Perry D, Kim D, Metcalf. P and Honig J M 1994 J. Solid State Chem. 110. 208. 5. Rao C N R, Ganguly P, Singh K K and Mohan Ram.

Zinc nanoparticles in solution by laser ablation technique

Indian Academy of Sciences (India)

TECS

Fujiwara H, Yanagida S and Kamat P V 1999 J. Phys. Chem. B103 2589. Geohegan D B, Puretzky A A, Duscher G and Pennycook S J. 1998 Appl. Phys. Lett. 72 2987. Henglein A, Gutierrez M, Janata E and Ershov B G 1992 J. Phys. Chem. 96 4598. Hodak J H, Henglein A, Giersig M and Hartland G V 2000 J. Phys. Chem.

Triethylammonium salt of dimethyl diphenyldithiophosphates: Single ...

Indian Academy of Sciences (India)

Moreno-Esparza R 2010 Struct. Chem. 21 191. 24. Bajia S C 2011 Synth. React. Inorg. Met.-Org. Nano. Met. Chem. 41 746. 25. Khajuria R, Kumar S, Kour G, Anthal S, Gupta V K,. Kant R and Pandey S K 2014 J. Coord. Chem. 67 2925. 26. Kumar S, Khajuria R, Gupta V K, Kant R and Pandey S. K 2014 Polyhedron 72 140.

A quantum - classical simulation of a multi-surface multi-mode ...

Indian Academy of Sciences (India)

Chem. Phys. 10 6388. [12] Sardar S, Paul A K, Sharma R and Adhikari S 2009 J. Chem. Phys. 130 144302. [13] Sardar S, Paul A K, and Adhikari S 2009 Mol. Phys. 23-24 2467. [14] Sardar S, Paul A K, Sharma R, Adhikari S, 2011 Int. J. Quant. Chem. 111 2741. [15] Dirac P A M, 1930 Proc. Cambridge Philos. Soc. 26 376. 5.

XRD and UV-Vis diffuse reflectance analysis of CeO2–ZrO2 solid ...

Indian Academy of Sciences (India)

Unknown

Bera P, Patil K C, Jayaram V, Subbanna G N and Hegde M S 2000 J. Catal. 196 293. 11. Busca G 1999 Phys. Chem. Chem. Phys. 1 723. 12. Sugunan S and Varghese B 1998 Indian J. Chem. A37 806. 13. Yamaguchi T 1994 Catal. Today 20 199. 14. Aramendia M A, Borau V, Jimenez C, Marinas J M, Porras A and Urbano ...

A new Cd(II)-containing ionic liquid: Synthesis, characterization and ...

Indian Academy of Sciences (India)

Administrator

Wormald P and Morris R E 2004 Nature 430 1012. 16. Seddon K R 1997 Chem. Technol. Biotechnol. 68 351. 17. Huddleston J G, Visser A E, Reichert W M, Willauer. H D, Broker G A and Rogers R D 2001 Green Chem. 3 156. 18. Reichert W M, Holbrey J D, Vigour K B, Morgan T. D, Broker G A and Rogers R D 2006 Chem.

Possible Outcomes of Coplanar High-eccentricity Migration: Hot Jupiters, Close-in Super-Earths, and Counter-orbiting Planets

Energy Technology Data Exchange (ETDEWEB)

Xue, Yuxin; Masuda, Kento; Suto, Yasushi, E-mail: yuxin@utap.phys.s.u-tokyo.ac.jp [Department of Physics, The University of Tokyo, Tokyo 113-0033 (Japan)

2017-02-01

We investigate the formation of close-in planets in near-coplanar eccentric hierarchical triple systems via the secular interaction between an inner planet and an outer perturber (Coplanar High-eccentricity Migration; CHEM). We generalize the previous work on the analytical condition for successful CHEM for point masses interacting only through gravity by taking into account the finite mass effect of the inner planet. We find that efficient CHEM requires that the systems should have m {sub 1}≪m {sub 0} and m {sub 1} ≪ m {sub 2}. In addition to the gravity for point masses, we examine the importance of the short-range forces, and provide an analytical estimate of the migration timescale. We perform a series of numerical simulations in CHEM for systems consisting of a Sun-like central star, giant gas inner planet, and planetary outer perturber, including the short-range forces and stellar and planetary dissipative tides. We find that most of such systems end up with a tidal disruption; a small fraction of the systems produce prograde hot Jupiters (HJs), but no retrograde HJ. In addition, we extend CHEM to super-Earth mass range, and show that the formation of close-in super-Earths in prograde orbits is also possible. Finally, we carry out CHEM simulation for the observed hierarchical triple and counter-orbiting HJ systems. We find that CHEM can explain a part of the former systems, but it is generally very difficult to reproduce counter-orbiting HJ systems.

Structure and intermolecular vibrations of 7-azaindole-water 2:1 ...

Indian Academy of Sciences (India)

Crespo-Hernández C E, Cohen B, Hare P M and Kohler. B 2004 Chem. Rev. 104 1977. 37. Löwdin P D 1966 Adv. Quant. Chem. 2 213. 38. Folmer D E, Poth L, Wisniewski E S and Castleman Jr. A W 1998 Chem. Phys. Lett. 287 1. 39. Folmer D E, Wisniewski E S, Hurley S M and Castleman. Jr A W 1999 Proc. Natl. Acad.

Fulltext PDF

Indian Academy of Sciences (India)

Joshi K C, Jain R and Garg S 1984 Pharmazie 40 21. 11. Joshi K C, Jain R and Sharma K 1990 Heterocycles. 31(3) 473. 12. Sharma K, Jain R and Joshi K C 1992 Indian J. Hetero- cycl. Chem. 1 189. 13. Lindwall H G and Maclennan J S 1932 J. Am. Chem. Soc. 54 4739. 14. Sharma V and Sharma K V 2009 E-J. Chem.

Model tool to describe chemical structures in XML format utilizing structural fragments and chemical ontology.

Science.gov (United States)

Sankar, Punnaivanam; Alain, Krief; Aghila, Gnanasekaran

2010-05-24

We have developed a model structure-editing tool, ChemEd, programmed in JAVA, which allows drawing chemical structures on a graphical user interface (GUI) by selecting appropriate structural fragments defined in a fragment library. The terms representing the structural fragments are organized in fragment ontology to provide a conceptual support. ChemEd describes the chemical structure in an XML document (ChemFul) with rich semantics explicitly encoding the details of the chemical bonding, the hybridization status, and the electron environment around each atom. The document can be further processed through suitable algorithms and with the support of external chemical ontologies to generate understandable reports about the functional groups present in the structure and their specific environment.

A Model for the Interfacial Kinetics of Phospholipase D Activity on Long-Chain Lipids

Science.gov (United States)

2013-07-01

7506–7513. 18. Zografi, G., R. Verger, and G. H. de Haas. 1971. Kinetic analysis of the hydrolysis of lecithin monolayers by phospholipase A. Chem...ChemBioChem. 9:2853–2859. 54. Albrecht, O., H. Gruler, and E. Sackmann. 1981. Pressure-composition phase diagrams of cholesterol/ lecithin , cholesterol...phosphatidic acid, and lecithin /phosphatidic acid fixed monolayers: a Langmuit film balance study. J. Colloid Interface Sci. 79:319–338. 55. Morris, A

Analysis of Cl…Cl and C–H…Cl intermolecular interactions ...

Indian Academy of Sciences (India)

Administrator

Rae A D and Desiraju G R 1993 J. Chem. Soc. Perkin. Trans. 2 2353. 7. Choudhury A R and Row T N G 2004 Cryst. Growth. Des. 4 47; Thalladi V R, Weiss H-C, Blдser D, Boese. R, Nangia A and Desiraju G R 1998 J. Am. Chem. Soc. 120 8702. 8. Chopra D, Cameron T S, Ferrara J D and Row T N G. 2006 J. Phys. Chem.

Green procedures for the chemoselective synthesis of acylals and ...

Indian Academy of Sciences (India)

Li C J and Chan T H 1999 Tetrahedron 55 11149. 5. Li C J 2005 Chem. Rev. 105 3095. 6. Greene T W and Wuts P G M 1999 In Protective Groups in Organic Synthesis 3rd ed. (New York: John Wiley and. Sons) p. 306. 7. Gregory M J 1970 J. Chem. Soc. B. 1201. 8. Jin T S, Sun G, Li Y W and Li T S 2002 Green Chem. 4. 255.

A new Mannich base and its transition metal (II) complexes ...

Indian Academy of Sciences (India)

Unknown

15. Ray R K and Kaufiman G B 1999 Inorg. Chim. Acta. 173 207. 16. Antosik S, Brown N M D, Mc Connelland A A and. Porte A L 1969 J. Chem. Soc. (A) 545. 17. Boas J F, Dunhil R H, Pilbrow J R, Srivastava R C and Smith T D 1969 J. Chem. Soc. (A) 94. 18. Hathaway B J and Tomlinson A A G 1970 Coord. Chem. Rev. 5 1.

Cyanide- and phenoxo-bridged heterobimetallic Fe(III)-Mn(III ...

Indian Academy of Sciences (India)

134 5083. 6. Jeon I R, Calancea S, Panja A, Piñero Cruz D M,. Koumousi E S, Dechambenoit P, Coulon C, Wattiaux A,. Rosa P, Mathonière C and Clérac R 2013 Chem. Sci. 4. 2463. 7. (a) Liu C M, Xiong R G, Zhang D Q and Zhu D B 2010J. Am. Chem. Soc. 132 4044; (b) Zhang Y Z and Sato O. 2010 Inorg. Chem. 49 1271.

Microenvironmental Regulation of Mammary Carcinogenesis

Science.gov (United States)

2009-06-01

F. et al., A selective activity-based probe for the papain family cysteine protease dipeptidyl peptidase I/cathepsin C. J Am Chem Soc 128 (17...based probe for the papain family cysteine protease dipeptidyl peptidase I/Cathepsin C. J Am Chem Society, 128: 5616- 5617. 39. Tan TT, Coussens LM...Bogyo, M. A selective activity-based probe for the papain family cysteine protease dipeptidyl peptidase I/cathepsin C. J Am Chem Soc 128, 5616-7

Artichoke (Cynara cardunculus L. var. scolymus) waste as a natural source of carbonyl trapping and antiglycative agents.

Science.gov (United States)

Maietta, Mariarosa; Colombo, Raffaella; Lavecchia, Roberto; Sorrenti, Milena; Zuorro, Antonio; Papetti, Adele

2017-10-01

The role of polyphenolic compounds extractable from artichoke solid wastes in the formation of advanced glycation end products (AGEs) was studied. Outer bracts and stems were extracted using different water-ethanol mixtures and HPLC-DAD analyses indicated aqueous and hydro-alcoholic 20:80 stem extracts as the richest in polyphenols. The samples were characterized in their phenolic composition (using mass spectrometry) and antioxidant capacity. Antiglycative capacity was evaluated by in vitro BSA-sugars (glucose, fructose, and ribose) and BSA-methylglyoxal (MGO) tests, formation of Amadori products assay, direct glyoxal (GO) and MGO trapping capacity. Results indicated both extracts as effective inhibitors of fructosamine formation and antiglycative agents. In particular, aqueous extract showed the best activity in the systems containing glucose and fructose, differently from ethanolic extract, that was demonstrated able to better inhibit AGEs formation when ribose or MGO act as precursors. Ethanolic extract was also shown to be able to trap MGO and GO, with efficiency increasing after 24hours of incubation time. These activities are partially correlated with the antioxidant effect of the extract, as demonstrated by the scavenger capacity against ABTS cation and DPPH stable radicals; this relationship is evident when the model system, containing protein incubated with ribose or MGO, is considered. The different activities of the tested extracts could probably be ascribed to the different composition in chlorogenic acids (CQAs), being aqueous extract richer in 1-CQA, 3-CQA, and 1,3-di-CQA, and ethanolic extract in 5-CQA, caffeic acid, 1,5-di-CQA. These findings support further investigations to study the stability of the different CQAs in simil-physiological conditions and the feasibility of artichoke waste as antiglycative agents in food or pharmacological preparations. 5-caffeoylquinic acid (PubChem CID 5280633); 3-caffeoylquinic acid (PubChem CID 1794427); 1

Studies in Aromatic and Amine Nitration.

Science.gov (United States)

1980-05-20

of Commerce, May 1978. 4. J. Hoggett , R. Moodie, F. Penton, and K. Schofield, Nitration and Aromatic Reactivity (Cambridge University Press, 1971). 5...Moodie, K. Schofield, and G. Tobin, J. Chem. Soc., Chem. Comm., 180 (1978); (b) J. Hoggett , R. Moodie, and K. Schofield, Chem. Comm. 605 (1969). 10. (a) S...Lawrence Livermore Laboratories (Received, 5th Februaty 1980; Com. 124.) 42 ’(a) J. Hoggett , R. B. Moodie, J. R. Penton, and K. Schofield, in ’Nitration

The Development and Study of Molecular Electronic Switches and their Field-Effect Transistor (FET) Device Properties

Science.gov (United States)

2015-02-27

Grand Rapids, MI) meetings and conferences. References 1. L.N Lucas, J.J.D. de Jong, J.H. van Esch, R.M. Kellogg , B.L. Berringa. Eur. J. Org...R.M. Kellogg , H.L. Feringa, H.L. Eur. J. Org. Chem., 2003, 155-166. 6. B. Qin, R. Yao, X. Zhao, H. Tian. Org. Biomol. Chem., 1, 2003, 2187-2191...7. L.N. Lucas, J.H. van Euch, R.M. Kellogg , B. Feringa. Chem. Comm., 1998, 2313-2314.

The dependence of lipid monolayer lipolysis on surface pressure.

OpenAIRE

Hall, D G

1992-01-01

Brönsted-Bjerrum theory [Brönsted (1922) Z. Phys. Chem. 102, 169-207; (1925) Z. Phys. Chem. 115, 337-364; Bjerrum (1924) Z. Phys. Chem. 108, 82-100] as applied to reactions at interfaces is used to interpret published data on the lipolysis of dinonanoyl phosphatidylcholine monolayers by pancreatic phospholipase A2. Reasonable quantitative agreement between theoretical and experimental results occurs when the reported effects of surface pressure on the amount of adsorbed enzyme are used togeth...

Retraction: Graphene-SnO2 nanocomposites decorated with quantum tunneling junctions: preparation strategies, microstructures and formation mechanism.

Science.gov (United States)

Simpson, Anna

2017-09-20

Retraction of 'Graphene-SnO 2 nanocomposites decorated with quantum tunneling junctions: preparation strategies, microstructures and formation mechanism' by Qingxiu Wang et al., Phys. Chem. Chem. Phys., 2014, 16, 19351-19357.

Combined impacts of nitrous acid and nitryl chloride on lower-tropospheric ozone: new module development in WRF-Chem and application to China

Science.gov (United States)

Zhang, Li; Li, Qinyi; Wang, Tao; Ahmadov, Ravan; Zhang, Qiang; Li, Meng; Lv, Mengyao

2017-08-01

Nitrous acid (HONO) and nitryl chloride (ClNO2) - through their photolysis - can have profound effects on the nitrogen cycle and oxidation capacity of the lower troposphere. Previous numerical studies have separately considered and investigated the sources/processes of these compounds and their roles in the fate of reactive nitrogen and the production of ozone (O3), but their combined impact on the chemistry of the lower part of the troposphere has not been addressed yet. In this study, we updated the WRF-Chem model with the currently known sources and chemistry of HONO and chlorine in a new chemical mechanism (CBMZ_ReNOM), and applied it to a study of the combined effects of HONO and ClNO2 on summertime O3 in the boundary layer over China. We simulated the spatial distributions of HONO, ClNO2, and related compounds at the surface and within the lower troposphere. The results showed that the modeled HONO levels reached up to 800-1800 ppt at the surface (0-30 m) over the North China Plain (NCP), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD) regions and that HONO was concentrated within a 0-200 m layer. In comparison, the simulated surface ClNO2 mixing ratio was around 800-1500 ppt over the NCP, YRD, and central China regions and was predominantly present in a 0-600 m layer. HONO enhanced daytime ROx (OH + HO2 + RO2) and O3 at the surface (0-30 m) by 2.8-4.6 ppt (28-37 %) and 2.9-6.2 ppb (6-13 %), respectively, over the three most developed regions, whereas ClNO2 increased surface O3 in the NCP and YRD regions by 2.4-3.3 ppb (or 5-6 %) and it also had a significant impact (3-6 %) on above-surface O3 within 200-500 m. The combined effects increased surface O3 by 11.5, 13.5, and 13.3 % in the NCP, YRD, and PRD regions, respectively. Over the boundary layer (0-1000 m), the HONO and ClNO2 enhanced O3 by up to 5.1 and 3.2 %, respectively, and their combined effect increased O3 by 7.1-8.9 % in the three regions. The new module noticeably improved O3

Simulating the meteorology and PM10 concentrations in Arizona dust storms using the Weather Research and Forecasting model with Chemistry (Wrf-Chem).

Science.gov (United States)

Hyde, Peter; Mahalov, Alex; Li, Jialun

2018-03-01

Nine dust storms in south-central Arizona were simulated with the Weather Research and Forecasting with Chemistry model (WRF-Chem) at 2 km resolution. The windblown dust emission algorithm was the Air Force Weather Agency model. In comparison with ground-based PM 10 observations, the model unevenly reproduces the dust-storm events. The model adequately estimates the location and timing of the events, but it is unable to precisely replicate the magnitude and timing of the elevated hourly concentrations of particles 10 µm and smaller ([PM 10 ]).Furthermore, the model underestimated [PM 10 ] in highly agricultural Pinal County because it underestimated surface wind speeds and because the model's erodible fractions of the land surface data were too coarse to effectively resolve the active and abandoned agricultural lands. In contrast, the model overestimated [PM 10 ] in western Arizona along the Colorado River because it generated daytime sea breezes (from the nearby Gulf of California) for which the surface-layer speeds were too strong. In Phoenix, AZ, the model's performance depended on the event, with both under- and overestimations partly due to incorrect representation of urban features. Sensitivity tests indicate that [PM 10 ] highly relies on meteorological forcing. Increasing the fraction of erodible surfaces in the Pinal County agricultural areas improved the simulation of [PM 10 ] in that region. Both 24-hr and 1-hr measured [PM 10 ] were, for the most part, and especially in Pinal County, extremely elevated, with the former exceeding the health standard by as much as 10-fold and the latter exceeding health-based guidelines by as much as 70-fold. Monsoonal thunderstorms not only produce elevated [PM 10 ], but also cause urban flash floods and disrupt water resource deliveries. Given the severity and frequency of these dust storms, and conceding that the modeling system applied in this work did not produce the desired agreement between simulations and

The ORNL Chemical Technology Division, 1950-1994

Energy Technology Data Exchange (ETDEWEB)

Jolley, R.L.; Genung, R.K.; McNeese, L.E.; Mrochek, J.E.

1994-10-01

This document attempts to reconstruct the role played by the Chemical Technology Division (Chem Tech) of the Oak Ridge National Laboratory (ORNL) in the atomic era since the 1940`s related to the development and production of nuclear weapons and power reactors. Chem Tech`s early contributions were landmark pioneering studies. Unknown and dimly perceived problems like chemical hazards, radioactivity, and criticality had to be dealt with. New chemical concepts and processes had to be developed to test the new theories being developed by physicists. New engineering concepts had to be developed and demonstrated in order to build facilities and equipment that had never before been attempted. Chem Tech`s role was chemical separations, especially uranium and plutonium, and nuclear fuel reprocessing. With diversification of national and ORNL missions, Chem Tech undertook R&D studies in many areas including biotechnology; clinical and environmental chemistry; nuclear reactors; safety regulations; effective and safe waste management and disposal; computer modeling and informational databases; isotope production; and environmental control. The changing mission of Chem Tech are encapsulated in the evolving activities.

Novel approach for optimization of fermentative condition for ...

African Journals Online (AJOL)

Jane

2011-07-20

Jul 20, 2011 ... School of Biochemical Engineering, Institute of Technology, Banaras Hindu University ... been applied for the optimization of a few biochemical ..... Methanol by Methylo bacterium Extorquens DSMZ. 1340. Iran J. Chem. Chem.

Rational design of protamine nanocapsules as antigen delivery carriers.

Science.gov (United States)

González-Aramundiz, José Vicente; Presas, Elena; Dalmau-Mena, Inmaculada; Martínez-Pulgarín, Susana; Alonso, Covadonga; Escribano, José M; Alonso, María J; Csaba, Noemi Stefánia

2017-01-10

Current challenges in global immunization indicate the demand for new delivery strategies, which could be applied to the development of new vaccines against emerging diseases, as well as to improve safety and efficacy of currently existing vaccine formulations. Here, we report a novel antigen nanocarrier consisting of an oily core and a protamine shell, further stabilized with pegylated surfactants. These nanocarriers, named protamine nanocapsules, were rationally designed to promote the intracellular delivery of antigens to immunocompetent cells and to trigger an efficient and long-lasting immune response. Protamine nanocapsules have nanometric size, positive zeta potential and high association capacity for H1N1 influenza hemagglutinin, a protein that was used here as a model antigen. The new formulation shows an attractive stability profile both, as an aqueous suspension or a freeze-dried powder formulation. In vitro studies showed that protamine nanocapsules were efficiently internalized by macrophages without eliciting significant toxicity. In vivo studies indicate that antigen-loaded nanocapsules trigger immune responses comparable to those achieved with alum, even when using significantly lower antigen doses, thus indicating their adjuvant properties. These promising in vivo data, alongside with their versatility for the loading of different antigens and oily immunomodulators and their excellent stability profile, make these nanocapsules a promising platform for the delivery of antigens. Protamine sulphate (PubChem SID: 7849283), Sodium Cholate (PubChem CID: 23668194), Miglyol (PubChem CID: 53471835), α tocopherol (PubChem CID: 14985), Tween® 20(PubChem CID: 443314), Tween® 80(PubChem CID: 5281955), TPGS (PubChem CID: 71406). Copyright © 2016 Elsevier B.V. All rights reserved.

Dynamics of Electronically Excited Species in Gaseous and Condensed Phase

Science.gov (United States)

1989-12-01

evaluate the Jacobian J v we make use of the numerical algorithm developed by Stodden and Micha 16, extending it to the equations of motion in...field of the average potential V(Q). The set of equations, Eq. (57), has been recently derived by Stodden and Micha 17 by evaluating directly the...Swaminathan, C. D. Stodden , and D. A. Micha, J. Chem. Phys 99 5501 (1989). 6 R. A. Marcus, Chem. Phys. Lett. 7, 525 (1970); J. Chem. Phys. 54, 3935 (1971); 56

Correction: The effect of recombination under short-circuit conditions on the determination of charge transport properties in nanostructured photoelectrodes.

Science.gov (United States)

Villanueva-Cab, J; Anta, J A; Oskam, G

2016-05-28

Correction for 'The effect of recombination under short-circuit conditions on the determination of charge transport properties in nanostructured photoelectrodes' by J. Villanueva-Cab et al., Phys. Chem. Chem. Phys., 2016, 18, 2303-2308.

Correction: Conceptual design of tetraazaporphyrin- and subtetraazaporphyrin-based functional nanocarbon materials: electronic structures, topologies, optical properties, and methane storage capacities.

Science.gov (United States)

Belosludov, Rodion V; Rhoda, Hannah M; Zhdanov, Ravil K; Belosludov, Vladimir R; Kawazoe, Yoshiyuki; Nemykin, Victor N

2017-08-02

Correction for 'Conceptual design of tetraazaporphyrin- and subtetraazaporphyrin-based functional nanocarbon materials: electronic structures, topologies, optical properties, and methane storage capacities' by Rodion V. Belosludov et al., Phys. Chem. Chem. Phys., 2016, 18, 13503-13518.

ARPA-NRL Laser Program - Semiannual Technical Report to Defense Advanced Research Projects Agency, 1 January 1974-30 June 1974

Science.gov (United States)

1975-04-01

Johnson and R.G, Fijw!’r, I. Chem. I’hys P. Millet , i. Salamero, n. Brunei, J. Goly, Ü. Bl.inc, and J, L. fuysslri...Chem Phys. 53, 1004 (1970). i «. wnem. ’Reference 4. ’P. Millet , Y. Salamero, H. Brunei, ,1. Galv. D. Blanc and J.L. reysster, J, Chem...1973) . 7. N. Djeu and R. Burnham, to be published. 8. P. Jean , M. Martin, J.P. Barrat, and J.L. Cojan, Compt. Rend. 264B, 609 (1967). 9. J.P

Monolithic Hierarchical Fractal Assemblies of Silica Nanoparticles Cross-Linked with Polynorbornene via ROMP: A Structure-Property Correlation from Molecular to Bulk through Nano

Science.gov (United States)

2012-08-23

285. (4) (a) Leventis, N.; Vassilaras, P.; Fabrizio, E. F.; Dass , A. J. Mater. Chem. 2007, 17, 1502−1508. (b) Leventis, N.; Sotiriou-Leventis, C.; Mulik...S.; Dass , A.; Schnobrich, J.; Hobbs, A.; Fabrizio, E. F.; Luo, H.; Churu, G.; Zhang, Y.; Lu, H. J. Mater. Chem. 2008, 18, 2475−2482. (c) Leventis, N...V.; Coder, D.; Loy, D. A. Chem. Mater. 2008, 20, 2845−2847. (12) Zhang, G.; Dass , A.; Rawashdeh, A-M. M.; Thomas, J.; Counsil, J. A.; Sotiriou

Substituent Effects and Bonding Characteristics in o- Benzoquinonediiminebis(bipyrdine) Ruthenium(II) Complexes

Science.gov (United States)

1992-10-23

C.; Dei, A.; Gatteschi , D.; Pardi, L Inorg. Chem. 1989, 2L 1476; (b) Benel, C.; Dei, A.; Gatteschi , D.; Ckdel, H. U.; Pardi, L Inorg. Ckem. 1989, 28...3091; (c) Benelli, C.; Dei, A.; Gatteschi , D.; Pardi, L Inorg.Chem. 1990,2& 3409. 16. Bruni, S.; Cariati, F.; Dei, A.; Gatteschi , D. Inog Cbim. Ata...1991, 186 157. 17. Dei, A.; Gatteschi , D.; Pardi, L; Barra, A. L; Brunel, L C. Chem, Py. Lett.. 1990, 175. 589; Dei, A.; Pardi, L Inorg, Chim.Acta

Calculation of Kinetic Data for Processes Leading to UV Signatures

Science.gov (United States)

1989-03-31

Jv we make use of the numerical algorithm developed by Stodden and Micha 17, extending it to the equations of motion in curvilinear coordinates. To be...in the field of the average potential V(Q). The set of equations (4.13’) have been recently derived by Stodden and Michat 5 in a more tedious.way by...B. Bloom, J. Chem. Phys. 83, 5703 (1985) 5 P. K. Swamninathan, C. D. Stodden , and D. A. Micha, J. Chem. Phys., in press (1989). 6 R. A. Marcus, Chem

Simulations of organic aerosol concentrations in Mexico City using the WRF-CHEM model during the MCMA-2006/MILAGRO campaign

Directory of Open Access Journals (Sweden)

G. Li

2011-04-01

Full Text Available Organic aerosol concentrations are simulated using the WRF-CHEM model in Mexico City during the period from 24 to 29 March in association with the MILAGRO-2006 campaign. Two approaches are employed to predict the variation and spatial distribution of the organic aerosol concentrations: (1 a traditional 2-product secondary organic aerosol (SOA model with non-volatile primary organic aerosols (POA; (2 a non-traditional SOA model including the volatility basis-set modeling method in which primary organic components are assumed to be semi-volatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. The MCMA (Mexico City Metropolitan Area 2006 official emission inventory is used in simulations and the POA emissions are modified and distributed by volatility based on dilution experiments for the non-traditional SOA model. The model results are compared to the Aerosol Mass Spectrometry (AMS observations analyzed using the Positive Matrix Factorization (PMF technique at an urban background site (T0 and a suburban background site (T1 in Mexico City. The traditional SOA model frequently underestimates the observed POA concentrations during rush hours and overestimates the observations in the rest of the time in the city. The model also substantially underestimates the observed SOA concentrations, particularly during daytime, and only produces 21% and 25% of the observed SOA mass in the suburban and urban area, respectively. The non-traditional SOA model performs well in simulating the POA variation, but still overestimates during daytime in the urban area. The SOA simulations are significantly improved in the non-traditional SOA model compared to the traditional SOA model and the SOA production is increased by more than 100% in the city. However, the underestimation during daytime is still salient in the urban area and the non-traditional model also fails to reproduce the high level of SOA concentrations in the

Singular mean-filed games

KAUST Repository

Cirant, Marco; Gomes, Diogo A.; Pimentel, Edgard A.; Sá nchez-Morgado, Hé ctor

2016-01-01

Here, we prove the existence of smooth solutions for mean-field games with a singular mean-field coupling; that is, a coupling in the Hamilton-Jacobi equation of the form $g(m)=-m^{-\\alpha}$. We consider stationary and time-dependent settings. The function $g$ is monotone, but it is not bounded from below. With the exception of the logarithmic coupling, this is the first time that MFGs whose coupling is not bounded from below is examined in the literature. This coupling arises in models where agents have a strong preference for low-density regions. Paradoxically, this causes the agents to spread and prevents the creation of solutions with a very-low density. To prove the existence of solutions, we consider an approximate problem for which the existence of smooth solutions is known. Then, we prove new a priori bounds for the solutions that show that $\\frac 1 m$ is bounded. Finally, using a limiting argument, we obtain the existence of solutions. The proof in the stationary case relies on a blow-up argument and in the time-dependent case on new bounds for $m^{-1}$.

Singular mean-filed games

KAUST Repository

Cirant, Marco

2016-11-22

Here, we prove the existence of smooth solutions for mean-field games with a singular mean-field coupling; that is, a coupling in the Hamilton-Jacobi equation of the form $g(m)=-m^{-\\\\alpha}$. We consider stationary and time-dependent settings. The function $g$ is monotone, but it is not bounded from below. With the exception of the logarithmic coupling, this is the first time that MFGs whose coupling is not bounded from below is examined in the literature. This coupling arises in models where agents have a strong preference for low-density regions. Paradoxically, this causes the agents to spread and prevents the creation of solutions with a very-low density. To prove the existence of solutions, we consider an approximate problem for which the existence of smooth solutions is known. Then, we prove new a priori bounds for the solutions that show that $\\\\frac 1 m$ is bounded. Finally, using a limiting argument, we obtain the existence of solutions. The proof in the stationary case relies on a blow-up argument and in the time-dependent case on new bounds for $m^{-1}$.

Watching Conformations of Biomolecules: a Microwave Spectroscopy Approach

Science.gov (United States)

Lopez, J. C.

2011-06-01

The combination of laser ablation with Fourier transform microwave spectroscopy in supersonic jets (LA-MB-FTMW) has made possible the gas-phase study of solid biomolecules with high melting points. In the experiment, solids are efficiently vaporized by a high-energy laser pulse, supersonically expanded into a evacuated Fabry-Perot cavity and characterised by their rotational spectra. Recent improvements such as the use of picosecond pulse lasers, new ablation nozzles and the extension of the range of the spectrometers to low frequecy have notably increased the sensitivity of our experimental setup. To date different α-, β- and γ-amino acids have been studied using this technique, making possible the characterization of their preferred conformations and gaining insight in the role of intramolecular interactions. Even in conformationally challenging systems the different rotamers of such biomolecules can be identified by rotational spectroscopy as can be illustrated by the assignment of six low-energy conformers in cysteine and aspartic acid, seven in serine and threonine,^a and nine in γ-amino butyric acid (GABA). In all cases the low-energy conformers have been conclusive identified from their experimental rotational and 14N quadrupole coupling constants. The spectra of neurotransmitters and of the nucleic acid bases uracil, thymine, cytosine and guanine have also been studied and their preferred conformers or tautomeric forms determined. The complexes between amino acids and nucleic acid bases with water have also been investigated to obtain information on the possible changes induced in the conformational or tautomeric preferences by the addition of solvent molecules. J. L. Alonso, C. Pérez, M. E. Sanz, J. C. López, S. Blanco, Phys. Chem. Chem. Phys. 11, 617-627 (2009) and references therein M. E. Sanz, J. C. López, J. L. Alonso, Phys. Chem. Chem. Phys., 12, 3573-3578 (2010) S. Blanco, J. C. López, S. Mata and J. L. Alonso, Angew. Chem. Int. Ed. 49, 9187

Hydrogen adsorption strength and sites in the metal organic framework MOF5: Comparing experiment and model calculations

Science.gov (United States)

Mulder, F. M.; Dingemans, T. J.; Schimmel, H. G.; Ramirez-Cuesta, A. J.; Kearley, G. J.

2008-07-01

Hydrogen adsorption in porous, high surface area, and stable metal organic frameworks (MOF's) appears a novel route towards hydrogen storage materials [N.L. Rosi, J. Eckert, M. Eddaoudi, D.T. Vodak, J. Kim, M. O'Keeffe, O.M. Yaghi, Science 300 (2003) 1127; J.L.C. Rowsell, A.R. Millward, K. Sung Park, O.M. Yaghi, J. Am. Chem. Soc. 126 (2004) 5666; G. Ferey, M. Latroche, C. Serre, F. Millange, T. Loiseau, A. Percheron-Guegan, Chem. Commun. (2003) 2976; T. Loiseau, C. Serre, C. Huguenard, G. Fink, F. Taulelle, M. Henry, T. Bataille, G. Férey, Chem. Eur. J. 10 (2004) 1373]. A prerequisite for such materials is sufficient adsorption interaction strength for hydrogen adsorbed on the adsorption sites of the material because this facilitates successful operation under moderate temperature and pressure conditions. Here we report detailed information on the geometry of the hydrogen adsorption sites, based on the analysis of inelastic neutron spectroscopy (INS). The adsorption energies for the metal organic framework MOF5 equal about 800 K for part of the different sites, which is significantly higher than for nanoporous carbon materials (˜550 K) [H.G. Schimmel, G.J. Kearley, M.G. Nijkamp, C.T. Visser, K.P. de Jong, F.M. Mulder, Chem. Eur. J. 9 (2003) 4764], and is in agreement with what is found in first principles calculations [T. Sagara, J. Klassen, E. Ganz, J. Chem. Phys. 121 (2004) 12543; F.M. Mulder, T.J. Dingemans, M. Wagemaker, G.J. Kearley, Chem. Phys. 317 (2005) 113]. Assignments of the INS spectra is realized using comparison with independently published model calculations [F.M. Mulder, T.J. Dingemans, M. Wagemaker, G.J. Kearley, Chem. Phys. 317 (2005) 113] and structural data [T. Yildirim, M.R. Hartman, Phys. Rev. Lett. 95 (2005) 215504].

Improving integrative searching of systems chemical biology data using semantic annotation.

Science.gov (United States)

Chen, Bin; Ding, Ying; Wild, David J

2012-03-08

Systems chemical biology and chemogenomics are considered critical, integrative disciplines in modern biomedical research, but require data mining of large, integrated, heterogeneous datasets from chemistry and biology. We previously developed an RDF-based resource called Chem2Bio2RDF that enabled querying of such data using the SPARQL query language. Whilst this work has proved useful in its own right as one of the first major resources in these disciplines, its utility could be greatly improved by the application of an ontology for annotation of the nodes and edges in the RDF graph, enabling a much richer range of semantic queries to be issued. We developed a generalized chemogenomics and systems chemical biology OWL ontology called Chem2Bio2OWL that describes the semantics of chemical compounds, drugs, protein targets, pathways, genes, diseases and side-effects, and the relationships between them. The ontology also includes data provenance. We used it to annotate our Chem2Bio2RDF dataset, making it a rich semantic resource. Through a series of scientific case studies we demonstrate how this (i) simplifies the process of building SPARQL queries, (ii) enables useful new kinds of queries on the data and (iii) makes possible intelligent reasoning and semantic graph mining in chemogenomics and systems chemical biology. Chem2Bio2OWL is available at http://chem2bio2rdf.org/owl. The document is available at http://chem2bio2owl.wikispaces.com.

Body composition of two human cadavers by neutron activation and chemical analysis

International Nuclear Information System (INIS)

Knight, G.S.; Beddoe, A.H.; Streat, S.J.; Hill, G.L.

1986-01-01

In vivo neutron activation analysis (NAA) is currently used to measure body composition in metabolic and nutritional studies in many clinical situations, but has not previously been validated by comparison with chemical analysis of human cadavers. Total body nitrogen (TBN) and chlorine (TBCl) were measured in two human cadavers by NAA before homogenization and chemical analysis (CHEM) after (cadaver 1: TBN, 1.47 NAA, 1.51 CHEM; TBCl, 0.144 NAA, 0.147 CHEM; cadaver 2: TBN, 0.576 NAA, 0.572 CHEM; TBCl, 0.0227 NAA, 0.0250 CHEM). The homogenates were also analyzed by NAA, and no significant differences were found, indicating that the effects of elemental inhomogeneity on the measurement of TBN and TBCl are insignificant. Total body water, fat, protein, minerals, and carbohydrates were measured chemically for each cadaver and compared with estimates for these compartments obtained from a body composition model, which when used in vivo involves NAA and tritium dilution. The agreement found justifies the use of the model for the measurement of changes in total body protein, water, and fat in sequential studies in groups of patients

Oxygen Evolution on Model Well-Characterised Mass-Selected Nanoparticles of RuOx

DEFF Research Database (Denmark)

Paoli, Elisa Antares; Masini, Federico; Frydendal, Rasmus

2014-01-01

. [6] M. Vukovic, J. Chem. Soc. Faraday Trans., vol. 86, no. 22, pp. 3743–3746, 1990. [7] R. Forgie, G. Bugosh, K. C. Neyerlin, Z. Liu, and P. Strasser, Electrochem. Solid-State Lett., vol. 13, no. 4, p. B36, 2010. [8] Y. Lee, J. Suntivich, K. J. May, E. E. Perry, and Y. Shao-horn, J. Phys. Chem C Lett......, and P. Strasser, ChemCatChem, vol. 2, no. 7, pp. 724–761, Jun. 2010. [2] A. Marshall, B. Børresen, G. Hagen, M. Tsypkin, and R. Tunold, Energy, vol. 32, no. 4, pp. 431–436, Apr. 2007. [3] P. C. K. Vesborg and T. F. Jaramillo, RSC Adv., vol. 2, no. 21, p. 7933, 2012. [4] F. J. Perez-Alonso, D. N. Mc......Carthy, A. Nierhoff, P. Hernandez-Fernandez, C. Strebel, I. E. L. Stephens, J. H. Nielsen, and I. Chorkendorff, Angew. Chem. Int. Ed. Engl., vol. 51, no. 19, pp. 4641–3, May 2012. [5] S. Murphy, R. M. Nielsen, C. Strebel, M. Johansson, and J. H. Nielsen, Carbon N. Y., vol. 49, no. 2, pp. 376–385, Feb. 2011...

Contribution of ship emissions to the concentration of PM2.5: A comprehensive study using AIS data and WRF/Chem model in Bohai Rim Region, China.

Science.gov (United States)

Chen, Dongsheng; Zhao, Na; Lang, Jianlei; Zhou, Ying; Wang, Xiaotong; Li, Yue; Zhao, Yuehua; Guo, Xiurui

2018-01-01

Compared with on-road vehicles, emission from ships is one of the least-regulated anthropogenic emission sources and non-negligible source of primary aerosols and gas-phase precursors of PM 2.5 . The Bohai Rim Region in China hosts dozens of large ports, two of which ranked among the top ten ports in the world. To determine the impact of ship emissions on the PM 2.5 concentrations over this region, two parts of works have been conducted in this study. First, a detailed ship emission inventory with high spatiotemporal resolution was developed based on Automatic Identification System (AIS) data. Then the WRF/Chem model was applied to modeling the impact of ship emissions by comparing two scenarios: with and without ship emissions. The results indicate that the total estimated ship emissions of SO 2 , NO X , PM 10 , PM 2.5 , CO, HC, and CO 2 from Bohai Rim Region in 2014 are 1.9×10 5 , 2.9×10 5 , 2.6×10 4 , 2.4×10 4 , 2.5×10 4 , 1.2×10 4 , and 1.3×10 7 tonnes, respectively. The modeling results indicate that the annual PM 2.5 concentrations increased by 5.9% on land areas of Bohai Rim Region (the continent within 115.2°E-124.3°E and 36.1°N-41.6°N) due to ship emissions. The contributions show distinctive seasonal variations of contributions, presenting highest in summer (12.5%) followed by spring (6.9%) and autumn (3.3%), and lowest in winter (0.9%). The contribution reaches up to 10.7% along the shoreline and down to 1.0% 200km inland. After examining the statistics of the modeling results during heavy and non-heavy haze days in July, it was found that 6 out of 9 cities around the Bohai Rim Region were observed with higher contributions from ship emissions during heavy haze days compared with non-heavy haze days. These results indicate that the impacts of ship emissions on the ambient PM 2.5 are non-negligible, especially for heavy haze days for most coastal cities in the Bohai Rim Region. Copyright © 2017 Elsevier B.V. All rights reserved.

Exploring the Structure of Nitrogen-Rich Ionic Liquids and Their Binding to the Surface of Oxide-Free Boron Nanoparticles

Science.gov (United States)

2013-01-29

results have to be interpreted with caution. Lovelock et al.61 have shown that clean surfaces can be obtained by sputtering for the [CnC1Im][Tf2N] IL...Licence, P. Langmuir 2006, 22, 9386−9392. (58) Hurisso, B. B.; Lovelock , K. R.; Licence, P. Phys. Chem. Chem. Phys. 2011, 13, 17737−48. (59) Zhang, H.; Cui...H. Langmuir 2009, 25, 2604−2612. (60) Zhang, Q.; Ma, X.; Liu, S.; Yang, B.; Lu, L.; He, Y.; Deng, Y. J. Mater. Chem. 2011, 21, 6864. (61) Lovelock , K

Biological and Catalytic Conversion of Sugars and Lignin Publications |

Science.gov (United States)

biorefinery lignins, ACS Sust. Chem. Eng. Lignin depolymerization with nitrate-intercalated hydrotalcite catalysts, ACS Catalysis Pyrolysis reaction networks for lignin model compounds: Unraveling thermal Free Energy, J. Amer. Chem. Soc. Process Design and Economics for the Conversion of Lignocellulosic

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

Shape tunable synthesis of Eu- and Sm-doped ZnO microstructures ...

Indian Academy of Sciences (India)

Shape tunable synthesis of Eu- and Sm-doped ZnO microstructures: a morphological ... different microstructures material at relatively low temper- ..... Chem. C 114. 2776. 5. Gao P X and Wang Z L 2003 J. Am. Chem. Soc. 125 11299. 6.

Identity of saropeptate, aurantiamide acetate and asperglaucide

Digital Repository Service at National Institute of Oceanography (India)

Wahidullah, S.; DeSouza, L.

stream_size 2 stream_content_type text/plain stream_name Orient_J_Chem_14_461.pdf.txt stream_source_info Orient_J_Chem_14_461.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Correction: General optimization procedure towards the design of a new family of minimal parameter spin-component-scaled double-hybrid density functional theory.

Science.gov (United States)

Roch, Loïc M; Baldridge, Kim K

2018-02-07

Correction for 'General optimization procedure towards the design of a new family of minimal parameter spin-component-scaled double-hybrid density functional theory' by Loïc M. Roch and Kim K. Baldridge, Phys. Chem. Chem. Phys., 2017, 19, 26191-26200.

Michelle L. Reed | NREL

Science.gov (United States)

troubleshooting High-throughput procedures In-house and external client training Method development High-pressure Pretreatment of Corn Stover Enables Facile Lignin Extraction," ACS Sustainable Chem. Eng. (2017) " ;Reductive Catalytic Fractionation of Corn Stover Lignin," ACS Sustainable Chem. Eng. (2016) "

Bull. Chem. Soc. Ethiop. 1996, 10(2)

African Journals Online (AJOL)

fingerprint indices are recommended. INTRODUCTION. The ever-increasing discharges .... The gas chromatographic profiles of all the samples are identical, so it may be assumed that these oils are from the same source materials, formed under different geological conditions. The isoprenoid and n-paraffinic composition of ...

Rad Chem data acquisition chassis users manual

International Nuclear Information System (INIS)

Jones, B.A.

1980-01-01

The Shiva Laser at LLL requires many forms of diagnostics to measure and analyze fusion experiments. This manual describes the operation of a Micro-Processor controlled data acquisition system designed at LLL to measure Neutron Activation during fusion experiments on the Shiva Laser

Wide Range Digitizer for Chem-Bio LIDAR

National Research Council Canada - National Science Library

Green, Norman; Moon, Raphael

2004-01-01

.... Typically, receiver amplifier gain is adjusted from time-to-time so that signal amplitude applied to the digitizer is not too large, resulting in a signal clipping, nor too small, resulting in poor digitizer resolution...

Boron-Dipyrromethene Dyes for Ion Recognition Studies

Indian Academy of Sciences (India)

pc

Singlet state energy levels of porphyrins with various cores λ abs ... Chem. Rev. 250, 468 (2006). M. Yedukondalu, M. Ravikanth, Coord. Chem. Rev. 255, 547 ..... 525 550 575 600 625 650 675 700 725 750. 0. 200. 400. 600. 800. 1000. 580.

Evaluation of the toxicity of organic matter in marine sediments

Digital Repository Service at National Institute of Oceanography (India)

Sarkar, A.

stream_size 3 stream_content_type text/plain stream_name 2_Int_Conf_Waste_Mgmt_Chem_Petrochem_Ind_Toxic_Mgmt_1991_258.pdf.txt stream_source_info 2_Int_Conf_Waste_Mgmt_Chem_Petrochem_Ind_Toxic_Mgmt_1991_258.pdf.txt Content...

NEW POLYTHIOPHENES WITH OLIGO(OXYETHYLENE) SIDE ...

African Journals Online (AJOL)

USER

The total molecular energies with. Bull. Chem. Soc. Ethiop. 2006, 20(1) .... With respect to Table 2 and 4 this matter is especially seen in ribose ring. Bull. Chem. Soc. Ethiop. 2006 ..... Mitsuya, H.; Broder, S. Nature (London) 1987, 325, 773. 2.

Bisoxazolinone from the mangrove Acanthus illicifolius

Digital Repository Service at National Institute of Oceanography (India)

De; Wahidullah, S.; Mishra, P.D

stream_size 3 stream_content_type text/plain stream_name Indian_J_Chem_B_36_1079.pdf.txt stream_source_info Indian_J_Chem_B_36_1079.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset=ISO-8859-1 ...

Exercises in Computational Chemistry

DEFF Research Database (Denmark)

Spanget-Larsen, Jens

2016-01-01

A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16).......A selection of HyperChem© PC-exercises in computational chemistry. Answers to most questions are appended (Roskilde University 2014-16)....

Chemical Technology Division Comprehensive Self-Assessment and Upgrade Program (CSAUP). Performance Objectives and Criteria

International Nuclear Information System (INIS)

1990-05-01

The U.S. Department of Energy (DOE) has placed strong emphasis on a new way of doing business patterned on the lessons learned in the nuclear power industry after the accident at Three Mile Island Unit 2. The new way relies on strict adherence to policies and procedures, a greatly expanded training program, and much more rigor and formality in operations. Another key element is more visible oversight by upper management and auditability by DOR Although the Chemical Technology Division (Chem Tech) has functioned in a safe manner since its beginning, the policies and methods of the past are no longer appropriate. Therefore, in accordance with these directives, Chem Tech is improving its operational performance by making a transition to greater formality in the observance of policies and procedures and a more deliberate consideration of the interrelationships between organizations at ORNL. This transition to formality is vitally important because both our staff and our facilities are changing with time. For example, some of the inventors and developers of the processes and facilities in use are now ''passing the torch'' to the next generation of Chem Tech staff. Our faculties have also served us well for many years, but the newest of these are now over 20 years old. All have increasing needs of refurbishment and repair, and some of the older ones need to be replaced. The Comprehensive Self-Assessment and Upgrade Program (CSAUP) has been patterned on a similar activity performed at the High Flux Isotope Reactor. Using the Draft DOE Performance Objectives and Criteria for Technical Safety Appraisals (May 1987) as a starting point, it was determined that 14 functional areas for evaluation listed in the report were suitable for Chem Tech use. An additional 5 functional areas were added for completeness since Chem Tech has a broader set of missions than a reactor facility. The Performance Objectives and Criteria (POC) for each functional area in the DOE report were

Analysis of CO in the tropical troposphere using Aura satellite data and the GEOS-Chem model: insights into transport characteristics of the GEOS meteorological products

Directory of Open Access Journals (Sweden)

Junhua Liu

2010-12-01

Full Text Available We use the GEOS-Chem chemistry-transport model (CTM to interpret the spatial and temporal variations of tropical tropospheric CO observed by the Microwave Limb Sounder (MLS and the Tropospheric Emission Spectrometer (TES. In so doing, we diagnose and evaluate transport in the GEOS-4 and GEOS-5 assimilated meteorological fields that drive the model, with a particular focus on vertical mixing at the end of the dry season when convection moves over the source regions. The results indicate that over South America, deep convection in both GEOS-4 and GEOS-5 decays at too low an altitude early in the wet season, and the source of CO from isoprene in the model (MEGAN v2.1 is too large, causing a lag in the model's seasonal maximum of CO compared to MLS CO in the upper troposphere (UT. TES and MLS data reveal problems with excessive transport of CO to the eastern equatorial Pacific and lofting in the ITCZ in August and September, particularly in GEOS-4. Over southern Africa, GEOS-4 and GEOS-5 simulations match the phase of the observed CO variation from the lower troposphere (LT to the UT fairly well, although the magnitude of the seasonal maximum is underestimated considerably due to low emissions in the model. A sensitivity run with increased emissions leads to improved agreement with observed CO in the LT and middle troposphere (MT, but the amplitude of the seasonal variation is too high in the UT in GEOS-4. Difficulty in matching CO in the LT and UT implies there may be overly vigorous vertical mixing in GEOS-4 early in the wet season. Both simulations and observations show a time lag between the peak in fire emissions (July and August and in CO (September and October. We argue that it is caused by the prevailing subsidence in the LT until convection moves south in September, as well as the low sensitivity of TES data in the LT over the African Plateau. The MLS data suggest that too much CO has been transported from fires in northern Africa to the UT

Improving integrative searching of systems chemical biology data using semantic annotation

Directory of Open Access Journals (Sweden)

Chen Bin

2012-03-01

Full Text Available Abstract Background Systems chemical biology and chemogenomics are considered critical, integrative disciplines in modern biomedical research, but require data mining of large, integrated, heterogeneous datasets from chemistry and biology. We previously developed an RDF-based resource called Chem2Bio2RDF that enabled querying of such data using the SPARQL query language. Whilst this work has proved useful in its own right as one of the first major resources in these disciplines, its utility could be greatly improved by the application of an ontology for annotation of the nodes and edges in the RDF graph, enabling a much richer range of semantic queries to be issued. Results We developed a generalized chemogenomics and systems chemical biology OWL ontology called Chem2Bio2OWL that describes the semantics of chemical compounds, drugs, protein targets, pathways, genes, diseases and side-effects, and the relationships between them. The ontology also includes data provenance. We used it to annotate our Chem2Bio2RDF dataset, making it a rich semantic resource. Through a series of scientific case studies we demonstrate how this (i simplifies the process of building SPARQL queries, (ii enables useful new kinds of queries on the data and (iii makes possible intelligent reasoning and semantic graph mining in chemogenomics and systems chemical biology. Availability Chem2Bio2OWL is available at http://chem2bio2rdf.org/owl. The document is available at http://chem2bio2owl.wikispaces.com.

Fiber optic field analytical instrumentation in place of quarterly compliance monitoring

International Nuclear Information System (INIS)

Henshaw, J.M.

1995-01-01

ChemSensor reg-sign is a new field analytical tool capable of in situ, real time measurements of organics in water. The purpose of this paper is to describe the application of this new instrument to the ongoing monitoring of petroleum contaminated ground water. The sensing element in ChemSensor incorporates a short optical fiber core with a hydrophobic/organophilic chemical coating. Light is launched into the fiber from a light emitting diode and detected at the opposite end by a photodiode. When the sensor is immersed in water containing organics, the organics partition into the organophilic coating and change the effective refractive index of he coating allowing light to escape. The resultant loss of light reaching the detector correlates to the concentration of organics present. It has been demonstrated through extensive field tests that response factors developed for ChemSensor allow it to be used as an accurate indication of BTEX contamination present. A large scale field test with an environmental consultant and a petroleum company was conducted to gain confidence in the correlation of ChemSensor to laboratory methods. As a result of this study, a case was made to the state regulators for substitution of a portion of the quarterly compliance monitoring with ChemSensor. This program has the potential to save the petroleum company thousands in laboratory analytical costs per year. This paper discusses the application of ChemSensor to sites contaminated by gasoline as well as the collection and interpretation of the data

Correction: Electronic structure of the boron fullerene B14 and its silicon derivatives B13Si+, B13Si- and B12Si2: a rationalization using a cylinder model.

Science.gov (United States)

Van Duong, Long; Nguyen, Minh Tho

2016-08-28

Correction for 'Electronic structure of the boron fullerene B 14 and its silicon derivatives B 13 Si + , B 13 Si - and B 12 Si 2 : a rationalization using a cylinder model' by Long Van Duong et al., Phys. Chem. Chem. Phys., 2016, 18, 17619-17626.

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.; Mann, K.; Roitman, J.N.; Yatskievych, G.;. Proksch, M.; Proksch, P. J. Plant. Physiol., 1987, 131, 37. Adityachaudhury, N.; Rose, P.C. Int. Symp. Chem. Nat. Prod., 1978, 2, 183,. Berdwaj, D.K.; Jain, R.K.: Munjal, A.; Prasher, M. Indian J. Chem., ...

Chiral and achiral helical coordination polymers of zinc and ...

Indian Academy of Sciences (India)

rality depends on formation of cis coordination geom- etry around the ..... lographic Data Centre via www.ccdc.cam.ac.uk/data_ .... 324; (b) Han L and Hong M 2005 Inorg. Chem. Com ... Kang Y, Chen S, Wang F, Zhang J and Bu X 2011 Chem.

Drug: D10144 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available HCl D10144.gif ... Other ... DG01718 ... Drugs for addictive disorder ... DG01716 ... Drugs for alcohol dependence Chem...ical group: DG01756 ... Treatment of alcohol dependence ... CAS: 1179819-25-0 PubChem: 135626862 ChEMBL: CHEMBL2105746 LigandBox: D10144 ...

Synthesis of substituted guanidines using Zn–Al hydrotalcite catalyst

Indian Academy of Sciences (India)

Zn–Al HT was prepared by co-precipitation method and charac- terized by ... tion of highly functionalized guanidines.4 Linton et al. explained a ..... Pi C, Zhu Z, Weng L, Chen Z and Zhou X 2007 Chem. Commun. ... J P 2000 J. Mater. Chem.

Chemical Technology Division: Progress report, January 1, 1987--June 30, 1988

Energy Technology Data Exchange (ETDEWEB)

1989-02-01

This progress report summarizes the research and development efforts conducted in the Chemical Technology Division (Chem Tech) during the period January 1, 1987, to June 30, 1988. The following major areas are covered: waste management and environmental programs, radiochemical and reactor engineering programs, basic science and technology, Nuclear Regulatory Commission programs, and administrative resources and facilities. The Administrative Summary, an appendix, presents a comprehensive listing of publications, oral presentations, awards and recognitions, and patents of Chem Tech staff members during this period. A staffing level and financial summary and lists of seminars and Chem Tech consultants for the period are also included.

Chemical Technology Division: Progress report, January 1, 1987--June 30, 1988

International Nuclear Information System (INIS)

1989-02-01

This progress report summarizes the research and development efforts conducted in the Chemical Technology Division (Chem Tech) during the period January 1, 1987, to June 30, 1988. The following major areas are covered: waste management and environmental programs, radiochemical and reactor engineering programs, basic science and technology, Nuclear Regulatory Commission programs, and administrative resources and facilities. The Administrative Summary, an appendix, presents a comprehensive listing of publications, oral presentations, awards and recognitions, and patents of Chem Tech staff members during this period. A staffing level and financial summary and lists of seminars and Chem Tech consultants for the period are also included

Characterization and H2-O2 reactivity of noble nano-metal tailored single wall nano-carbons

International Nuclear Information System (INIS)

K Kaneko; T Itoh; E Bekyarova; H Kanoh; S Utsumi; H Tanaka; M Yudasaka; S Iijima; S Iijima

2005-01-01

Full text of publication follows: Single wall carbon nano-tube (SWNT) and single wall carbon nano-horn (SWNH) have nano-spaces in their particles and the nano-spaces become open by oxidation. In particular, SWNH forms a unique colloidal structure which has micropores and meso-pores between the SWNH particles. Although non-treated SWNH colloids have quasi-one dimensional nano-pores [1], oxidized SWNH colloids have both of interstitial and internal nano-pores [2-5]. SWNH colloids show excellent supercritical methane storage ability [6], molecular sieving effect [7], and unique hydrogen adsorption characteristic [8]. Selective adsorptivity of SWNH colloids for H 2 and D 2 due to uncertainty principle of those molecules was shown [9-10]. As SWNH has no metallic impurities, we can study the effect of tailoring of metallic nano-particles on the surface activities of SWNH [11]. We tailored Pd or Pt nano-particles on SWNH and SWNH oxidized at 823 K (ox-SWNH) using poly[(2-oxo-pyrrolidine-1-yl)ethylene]. The oxidation of SWNH donates nano-scale windows to the single wall. The tailored metal amount was determined by TG analysis. TEM showed uniform dispersion of nano-metal particles of 2-3 nm in the diameter on SWNH. The nitrogen adsorption amount of SWNH oxidized decreases by tailoring, indicating that nano-particles are attached to the nano-scale windows. The electronic states of tailored metals were characterized by X-ray photoelectron spectroscopy. The surface activities of Pd tailored SWNH and ox-SWNH were examined for the reaction of hydrogen and oxygen near room temperature. The catalytic reactivities of Pd tailored SWNH and ox-SWNH were 4 times greater than that of Pd-dispersed activated carbon. The temperature dependence of the surface activity will be discussed with the relevance to the tube porosity. References [1] T. Ohba et al, J. Phys. Chem. In press. [2] S. Utsumi et al, J. Phys. Chem. In press. [3] C.- Min Yang, et al. Adv. Mater. In press. [4]C.M. Yang, J

Self-assembly of azobenzene based side-chain liquid crystalline ...

Indian Academy of Sciences (India)

. Grimsdale A C and Müllen K 2005 Angew. Chem. Int. Ed. 44 5592. 20. Serpe M J and Craig S L 2007 Langmuir 23 1626. 21. Delphia Shalini Rosalyn P, Senthil S, Kannan P, Vinitha. G and Ramalingam A 2007 J. Phys. Chem. Solids 68. 1812.

Structural, magnetic and magnetotransport properties of La0⋅7 ...

Indian Academy of Sciences (India)

Unknown

Carvajal 1993 Physica B192 55. 11. Randaelli P G, Marezio M, Hwang H Y and Cheong. S-W 1996 J. Solid State Chem. 122 444. 12. Barnabé A, Millange F, Maignan A, Hervieu M,. Raveau B, Van Tendeloo G and Laffez P 1998 Chem. Mater.

Crystal and Vibrational Structure of Energetic 3,5-dinitro 1,3,5-oxadiazinane (DOD) by Single Crystal X-ray Diffractometry and Raman Spectroscopy

Science.gov (United States)

2018-03-19

480. 8. Ishchenko MA, Nikolaev VD, Sokolov, AA. Cyclic nitraza ethers from 1,3-dinitro-1,3-diazapropane. Russ J Org Chem. 1996;32(3):460. 9...Ishchenko, MA, Nikolaev VD, Sokolov AA. Formaldehyde acetals and polyoxymethylene ethers derived from (hydroxymethyl)-N-nitroamines. Russ J Org Chem

Saturation Transfer Difference NMR as an Analytical Tool for Detection and Differentiation of Plastic Explosives on the Basis of Minor Plasticizer Composition

Science.gov (United States)

2015-05-01

Liquid Chromatography (HPLC) Method. Fresenius J. Anal. Chem. 1996, 356, 445–451. 5. Ivy, M.A.; Gallagher, L.T.; Ellington, A.D.; Anslyn, E.V...6. Wypych, G. Handbook of Plasticizers; ChemTec Publishing: Ontario, Canada, 2004. 7. Mayer, M.; Meyer, B . Characterization of Ligand Binding

Cage Compounds as Potential Energetic Oxidizers: A Theoretical Study of a Cage Isomer of N2O3

Science.gov (United States)

2014-07-01

Laboratory. References [1] P. W. M. Jacobs, H. M. Whitehead, Decomposition and Combustion of Ammonium Perchlorate, Chem. Rev., 1969, 69 551- 590 . [2...and Symmetric Dinitrogen Trioxide in Nitric-Oxide Matrices by Raman and Infrared- Spectroscopy, J. Phys. Chem. 1983, 87, 1113- 1120. [14] a) X. Wang

Engineering with macromolecules : from supramolecular chemistry to defined nanomaterials

NARCIS (Netherlands)

Lohmeijer, B.G.G.; Gohy, J.M.W.; Schubert, U.S.

2003-01-01

By uniting concepts from polymer chem. and supramol. chem. we present a new approach for the prepn. of functional nano-materials. Amphiphilic diblock and triblock copolymers were constructed in such a way that a bisterpyridine ruthenium complex acts as the linker between the two constituting blocks.

Combined impacts of nitrous acid and nitryl chloride on lower-tropospheric ozone: new module development in WRF-Chem and application to China

Directory of Open Access Journals (Sweden)

L. Zhang

2017-08-01

Full Text Available Nitrous acid (HONO and nitryl chloride (ClNO2 – through their photolysis – can have profound effects on the nitrogen cycle and oxidation capacity of the lower troposphere. Previous numerical studies have separately considered and investigated the sources/processes of these compounds and their roles in the fate of reactive nitrogen and the production of ozone (O3, but their combined impact on the chemistry of the lower part of the troposphere has not been addressed yet. In this study, we updated the WRF-Chem model with the currently known sources and chemistry of HONO and chlorine in a new chemical mechanism (CBMZ_ReNOM, and applied it to a study of the combined effects of HONO and ClNO2 on summertime O3 in the boundary layer over China. We simulated the spatial distributions of HONO, ClNO2, and related compounds at the surface and within the lower troposphere. The results showed that the modeled HONO levels reached up to 800–1800 ppt at the surface (0–30 m over the North China Plain (NCP, the Yangtze River Delta (YRD, and the Pearl River Delta (PRD regions and that HONO was concentrated within a 0–200 m layer. In comparison, the simulated surface ClNO2 mixing ratio was around 800–1500 ppt over the NCP, YRD, and central China regions and was predominantly present in a 0–600 m layer. HONO enhanced daytime ROx (OH + HO2 + RO2 and O3 at the surface (0–30 m by 2.8–4.6 ppt (28–37 % and 2.9–6.2 ppb (6–13 %, respectively, over the three most developed regions, whereas ClNO2 increased surface O3 in the NCP and YRD regions by 2.4–3.3 ppb (or 5–6 % and it also had a significant impact (3–6 % on above-surface O3 within 200–500 m. The combined effects increased surface O3 by 11.5, 13.5, and 13.3 % in the NCP, YRD, and PRD regions, respectively. Over the boundary layer (0–1000 m, the HONO and ClNO2 enhanced O3 by up to 5.1 and 3.2 %, respectively, and their combined effect increased O

Kanishka Biswas

Indian Academy of Sciences (India)

Kanishka Biswas

(Solid state inorganic chemistry). (Metal chalcogenide chemistry). Manoj K. Jana. Satya N. Guin. Ananya Banik. Subhajit. Roychowdhury. Manisha Samanta Ekashmi. Rathore. Sujoy Saha. Thermoelectrics. Guin et al. Energy Environ. Sci., 2013, 6, 2603. Guin et al. J. Mater. Chem. A 2014, 2, 4324. Guin, et al. J. Am. Chem.

Restricting rotation of triple bond through π-stacking interactions in ...

Indian Academy of Sciences (India)

SANKARARAMAN

For various X and Y activation barrier range from 42-79 kJ/mole. Vögtle, F., et.al., Angew. Chem. Int. Ed., 1979, 18, 159. Toyota, S., et.al., Bull. Chem. Soc. Jpn, 2000, 73, 205 and 2591. Toyota, S., et.al., Tetrahedron Lett., 2001, 57, 3521.

A CONVENIENT THREE-COMPONENT SYNTHESIS OF ...

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1College of Chemistry, Chemical Engineering and Food Safety, Bohai University, Jinzhou. 121013 ... Most reactions are performed within a short reaction time. ..... Shaterian, H.R.; Hosseinian, A.; Ghashang, M. Chin. J. Chem. 2009, 27, 821. 7. Heravi, M.M.; Tavakoli-Hoseini, N.; Bamoharram, F.F. Green Chem. Lett. Rev.

Improved covalent functionalization of multi-walled carbon ...

Indian Academy of Sciences (India)

Carbon nanotubes (CNTs) play a fundamental role in the rapidly developing .... using field emission scanning electron microscopy (FE-. SEM). The images ..... The limiting oxygen index (LOI) is the minimum concen- tration of oxygen that .... Chem. Lett. 22 185. [19] Mallakpour S and Zadehnazari A 2014 J. Solid State Chem.

State resolved rotational excitation cross-sections and rates in H2 + H2 collisions

International Nuclear Information System (INIS)

Sultanov, Renat A.; Guster, Dennis

2006-01-01

Rotational transitions in molecular hydrogen collisions are computed. The two most recently developed potential energy surfaces for the H 2 -H 2 system are used from the following works: [A.I. Boothroyd, P.G. Martin, W.J. Keogh, M.J. Peterson, J. Chem. Phys., 116 (2002) 666; P. Diep, J.K. Johnson, J. Chem. Phys., 113 (2000) 3480; P. Diep, J.K. Johnson, J. Chem. Phys., 112 (2000) 4465]. Cross-sections for rotational transitions 00 → 20, 22, 40, 42, 44 and corresponding rate coefficients are calculated using a quantum-mechanical approach. Results are compared for a wide range of kinetic temperatures 300 K ≤ T≤ 3000 K

Correction: Towards the rationalization of catalytic activity values by means of local hyper-softness on the catalytic site: a criticism about the use of net electric charges.

Science.gov (United States)

Martínez-Araya, Jorge Ignacio; Grand, André; Glossman-Mitnik, Daniel

2016-01-28

Correction for 'Towards the rationalization of catalytic activity values by means of local hyper-softness on the catalytic site: a criticism about the use of net electric charges' by Jorge Ignacio Martínez-Araya et al., Phys. Chem. Chem. Phys., 2015, DOI: 10.1039/c5cp03822g.

Developing Design Criteria and Scale Up Methods for Water-Stable Metal-Organic Frameworks for Adsorption Applications

Science.gov (United States)

2014-09-08

Berthelot mixing rules were applied to calculate intermolecular van der Waals interactions between water and framework atoms. All transition state...Rodrigues, A. E. J. Chem. Eng. Data 2004, 49 (4), 1095-1101. (7) Franchi , R. S.; Harlick, P. J. E.; Sayari, A. Ind. Eng. Chem. Res. 2005, 44 (21), 8007

Application of coalescence and breakup models in a discrete bubble model for bubble columns

NARCIS (Netherlands)

van den Hengel, E.I.V.; Deen, N.G.; Kuipers, J.A.M.

2005-01-01

In this work, a discrete bubble model (DBM) is used to investigate the hydrodynamics, coalescence, and breakup occurring in a bubble column. The DBM, originally developed by Delnoij et al. (Chem. Eng. Sci. 1997, 52, 1429-1458; Chem. Eng. Sci. 1999, 54, 2217-2226),1,2 was extended to incorporate

dichlorodiazene dioxides using levulinic acid under solvent-free

Indian Academy of Sciences (India)

Administrator

43 599; (b) Tchou- bar B and Sackur O ... Bremeyer N, Smith S C, Ley S V and Gaunt M J. 2004 Angew. ... Bellesia F, Ghelfi F, Pagnoni U M and Pinetti A 1990. J. Chem. Res. ... Kronenthal D, Huang M H and Nugent W A 2004 J. Org. Chem.

Rescue of Drosophila Melanogaster l(2)35Aa lethality is only mediated by polypeptide GalNAc-transferase pgant35A, but not by the evolutionary conserved human ortholog GalNAc-transferase-T11

DEFF Research Database (Denmark)

Bennett, Eric P; Chen, Ya-Wen; Schwientek, Tilo

2010-01-01

The Drosophila l(2)35Aa gene encodes a UDP-N-acetylgalactosamine: Polypeptide N-acetylgalactosaminyltransferase, essential for embryogenesis and development (J. Biol. Chem. 277, 22623-22638; J. Biol. Chem. 277, 22616-22). l(2)35Aa, also known as pgant35A, is a member of a large evolutionarily con...

SYNTHESIS AND IN VITRO ANTIMICROBIAL EVALUATION OF 5 ...

African Journals Online (AJOL)

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arabjc.2011.09.018. 25. Mansoor, S.S.; Aswin, K.; Logaiya, K.; Sudhan, S.P.N. J. Saudi Chem. Soc. 2012, DOI: http://dx.doi.org/10.1016/j.jscs.2012.04.008. 26. Mansoor, S.S.; Aswin, K.; Logaiya, K.; Sudhan, S.P.N. J. Saudi Chem. Soc. 2012, DOI:.

75 FR 51678 - Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Final Exclusion

Science.gov (United States)

2010-08-23

...: Environmental Protection Agency. ACTION: Final rule. SUMMARY: Environmental Protection Agency (EPA) is granting.... How much waste did OxyChem propose to delist? C. How did OxyChem sample and analyze the waste data in... proposed rule? V. Statutory and Executive Order Reviews I. Overview Information A. What action is EPA...

Studies on electron transfer reactions: Reduction of heteropoly 10 ...

Indian Academy of Sciences (India)

Administrator

, Amat E, Genestar C and Palou J 1987 J. Radioanalytical and Nuclear Chem. 116 459. 9. Martin J F and Spence J T 1970 J. Phys. Chem. 74. 3589. 10. Ayoko G A and Olatunji M A 1983 Polyhedron 2. 577. 11. Sun J and Stanbury D M 2002 J.

Fluorescence anisotropy of acridinedione dyes in glycerol: Prolate ...

Indian Academy of Sciences (India)

TECS

61 5083. 26. Srividya N, Ramamurthy P and Ramakrishnan V T. 1998 Spectrochim. Acta 54 245. 27. Venkatachalapathy B and Ramamurthy P 1999 Phys. Chem. Chem. Phys. 1 2223. 28. Indirapriyadharshini V K, Karunanithi P and Rama- murthy P 2001 Langmuir 17 4056. 29. Thiagarajan V, Selvaraju C, Padmamalar E J ...

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

International Nuclear Information System (INIS)

Michelini, M.D.C.; Russo, N.; Sicilia, E.

2007-01-01

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

Spec UV-Vis: An Ultraviolet-Visible Spectrophotometer Simulation

Science.gov (United States)

Papadopoulos, N.; Limniou, Maria; Koklamanis, Giannis; Tsarouxas, Apostolos; Roilidis, Mpampis; Bigger, Stephen W.

2001-11-01

The software and its accompanying manual can be used to illustrate the recording of an absorption spectrum and the Beer-Lambert law (5-7) as well as various aspects of acid-base indicators such as the spectrophotometric determination of pKa (8), the isosbestic point (6, 9), and distribution diagrams (10, 11). Literature Cited Shiowatana, J. J. Chem. Educ. 1997, 74, 730. Altemose, I. R. J. Chem. Educ. 1986, 63, A216, A262. Piepmeier, E. H. J. Chem. Educ. 1973, 50, 640. Lott, P. F. J. Chem. Educ. 1968, 45, A89, A169, A182, A273. Skoog, D. A.; West, D. M.; Holler, F. J. Fundamentals of Analytical Chemistry, 7th ed.; Saunders College Publishing: Fort Worth, TX, 1996, Chapters 22-24. Christian, G. D. Analytical Chemistry, 5th ed.; Wiley: New York, 1994; Chapter 14. Kennedy, J. H. Analytical Chemistry--Principles, 2nd ed.; Saunders College Publishing: New York, 1990; Chapters 11,12. Patterson, G. S. J. Chem. Educ. 1999, 76, 395. Harris, D. C. Quantitative Chemical Analysis, 5th ed.; Freeman: New York, 1997; Chapters 19, 20. Butler, J. N. Ionic Equilibrium--A Mathematical Approach; Addison-Wesley: Reading, MA, 1964; Chapter 5. Sawyer, C. A.; McCarty, P. L.; Parkin, G. F. Chemistry for Environmental Engineering, 4th ed.; McGraw-Hill: Singapore, 1994; Chapter 4.

Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Eggeman, Tim [ZeaChem Inc., Lakewood, CO (United States); O' Neill, Brian [ZeaChem Inc., Lakewood, CO (United States)

2016-08-17

ZeaChem Inc. and US DOE successfully demonstrated the ZeaChem process for producing sugars and ethanol from high-impact biomass feedstocks. The project was executed over a 5-year period under a $31.25 million cooperative agreement (80:20 Federal:ZeaChem cost share). The project was managed by dividing it into three budget periods. Activities during Budget Period 1 were limited to planning, permitting, and other pre-construction planning. Budget Period 2 activities included engineering, procurement, construction, commissioning, start-up and initial operations through the Independent Engineer Test Runs. The scope of construction was limited to the Chem Frac and Hydrogenolysis units, as the Core Facility was already in place. Construction was complete in December 2012, and the first cellulosic ethanol was produced in February 2013. Additional operational test runs were conducted during Budget Period 3 (completed June 2015) using hybrid poplar, corn stover, and wheat straw feedstocks, resulting in the production of cellulosic ethanol and various other biorefinery intermediates. The research adds to the understanding of the Chem Frac and Hydrogenolysis technologies in that the technical performance of each unit was measured, and the resulting data and operational experience can be used as the basis for engineering designs, thus mitigating risks for deployment in future commercial facilities. The Chem Frac unit was initially designed to be operated as two-stage dilute acid hydrolysis, with first stage conditions selected to remove the hemicellulose fraction of the feedstock, and the second stage conditions selected to remove the cellulose fraction. While the Chem Frac unit met or exceeded the design capacity of 10 ton(dry)/day, the technical effectiveness of the Chem Frac unit was below expectations in its initial two-stage dilute acid configuration. The sugars yields were low, the sugars were dilute, and the sugars had poor fermentability caused by excessive inhibitors

Mechanical Adaptivity as a Process: Implications to New Materials and Material System Design

Science.gov (United States)

2012-08-01

Mfg / Origami HT Thermal Shape Memory PhotoChem- Mechanical Autonomic Chemo-Mechanical Building Blocks Predictive Models...structure Farkas et al. Chaos 5 1995 Bishop et al. JACS, 2005 Controlling oscillations through medium selection and geometry Controlling...Additive Mfg / Origami HT Thermal Shape Memory PhotoChem- Mechanical Autonomic Chemo-Mechanical Building Blocks Predictive Models

How Much Weaker Are the Effects of Cations than Those of Anions?

DEFF Research Database (Denmark)

Morita, Takeshi; Westh, Peter; Nishikawa, Keilo

2014-01-01

We characterized the effects of K+ and Cs+ ions on the molecular organization of H2O by the 1-propanol probing methodology, previously developed by us (Phys. Chem. Chem. Phys. 2013, 15, 14548). The results indicated that both ions belong to the class of “hydration center”, which is hydrated by 4...

Influence of initial glycerol concentration upon bacterial cells ...

African Journals Online (AJOL)

user

Kinetics of winery wastewater from port wine production. Chem. Biochem. Eng. 25:493-499. Stemmet CP, Bartelds F, Van Der Schaaf J, Kuster BFM, Schouten JC. (2008). Influence of liquid viscosity and surface tension on the gas– liquid mass transfer coefficient for solid foam packings in co-current two-phase flow. Chem.

as a Novel Chiral Ligand for Catalysis of the Asymmetric Diels-Al

African Journals Online (AJOL)

NJD

2008-11-25

Nov 25, 2008 ... P.I. Arvidsson, T. Govender, H.G. Kruger, G.E.M. Maguire and T. Naicker,. 60 .... Ni(ClO4)2. 120. 60 ..... 4 G. Desimoni, G. Faita and K.A. Jorgensen, Chem. ... 27 D.A. Evans, S.J. Miller, T. Lectka and P. von Matt, J. Am. Chem.

SO2 Emissions and Lifetimes: Estimates from Inverse Modeling Using In Situ and Global, Space-Based (SCIAMACHY and OMI) Observations

Science.gov (United States)

Lee, Chulkyu; Martin Randall V.; vanDonkelaar, Aaron; Lee, Hanlim; Dickerson, RUssell R.; Hains, Jennifer C.; Krotkov, Nickolay; Richter, Andreas; Vinnikov, Konstantine; Schwab, James J.

2011-01-01

Top-down constraints on global sulfur dioxide (SO2) emissions are inferred through inverse modeling using SO2 column observations from two satellite instruments (SCIAMACHY and OMI). We first evaluated the S02 column observations with surface SO2 measurements by applying local scaling factors from a global chemical transport model (GEOS-Chem) to SO2 columns retrieved from the satellite instruments. The resulting annual mean surface SO2 mixing ratios for 2006 exhibit a significant spatial correlation (r=0.86, slope=0.91 for SCIAMACHY and r=0.80, slope = 0.79 for OMI) with coincident in situ measurements from monitoring networks throughout the United States and Canada. We evaluate the GEOS-Chem simulation of the SO2 lifetime with that inferred from in situ measurements to verity the applicability of GEOS-Chem for inversion of SO2 columns to emissions. The seasonal mean SO2 lifetime calculated with the GEOS-Chem model over the eastern United States is 13 h in summer and 48 h in winter, compared to lifetimes inferred from in situ measurements of 19 +/- 7 h in summer and 58 +/- 20 h in winter. We apply SO2 columns from SCIAMACHY and OMI to derive a top-down anthropogenic SO2 emission inventory over land by using the local GEOS-Chem relationship between SO2 columns and emissions. There is little seasonal variation in the top-down emissions (SO2 emissions (52.4 Tg S/yr from SCIAMACHY and 49.9 Tg S / yr from OMI) closely agrees with the bottom-up emissions (54.6 Tg S/yr) in the GEOS-Chem model and exhibits consistency in global distributions with the bottom-up emissions (r = 0.78 for SCIAMACHY, and r = 0.77 for OMI). However, there are significant regional differences.

Shape, size and temperature dependency of thermal expansion ...

Indian Academy of Sciences (India)

M GOYAL

2018-05-19

May 19, 2018 ... Oriental J. Chem.32(4), 2193 (2016), is extended in the present study using Qi and Wang model [Mater. Chem. Phys. ... Nanomaterials; shape factor; size effect; thermal expansion; equation of state. ... als are different from that of their bulk material. ..... and 1c along with the present calculated results. It is.

Upconversion studies in rare earth ions-doped lanthanide materials

Indian Academy of Sciences (India)

2014-02-08

Feb 8, 2014 ... studied samples in order to get the visible upconversion emission on 976 nm excitation. References. [1] F Azuel, Chem. Rev. 104, 139 (2004). [2] W M Yen, S Shionoya and H Yamamoto (eds), Practical applications of phosphors (CRC. Press, Taylor and Francis Group, 2006). [3] F Wang and X Liu, Chem.

One-pot synthesis of N-aryl 1,4-dihydropyridine derivatives and their ...

Indian Academy of Sciences (India)

12, December 2015, pp. 2201–2209. c Indian Academy of Sciences. ... e-mail: padimini_tamilenthi@yahoo.co.in. MS received 2 March 2015; revised 19 September 2015; accepted 20 September 2015. Abstract. ..... X, Schmidt J, Agrawal K C and Kishore V 1998 Bioorg. Med. Chem. 6 563. 4. Hantzsch A 1881 Chem. Ber.

76 FR 12619 - Airworthiness Directives; The Boeing Company 737-200, -200C, -300, -400, and -500 Series Airplanes

Science.gov (United States)

2011-03-08

..., Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone... paragraph. Note 1: For the purposes of this AD, a detailed inspection is defined as: ``An intensive visual... below the chem-milled step. If an external doubler covers the chem-milled step, but does not span it by...

191-IJBCS-Article-Dr A D V Ayansina

African Journals Online (AJOL)

RHUMSIKI

Effect of organic amendments on microbial biomass of a tropical soil treated with some ... A.D.V. AYANSINA and B.A. OSO / Int. J. Biol. Chem. Sci. 2(4): 417-424, 2008. 418 cultivation ... microorganisms and transformed to humic ... al., 1987). The application of organic manure (e.g. ..... J. Agric. Food Chem., 34: 746-749.

On the Need for Multiple Lists of Chemical Information

Directory of Open Access Journals (Sweden)

Jonathan Goodman

2000-01-01

Full Text Available Cambridge University Department of Chemistry has a list of University Chemistry Departments and Chemistry-related journals around the world: ChemSites (http://www.ch.cam.ac.uk/ChemSitesIndex.html. This article describes what makes it distinct from other lists, and justifies the existence of more than one such list.

Thermal Decomposition Mechanisms of Alkylimidazolium Ionic Liquids with CN-containing Anions

Science.gov (United States)

2014-11-01

S. P., Heintz, A., Corfield, J.-A., Deyko, A., Lovelock , K. R. J., Licence, P. and Jones, R. G. Journal of Physical Chemistry B, 2008, 112, 11734...Jones, R. G., Licence, P., Lovelock , K. R. J., Satterly, C. J. and Villar-Garcia, I. J. Phys. Chem. Chem. Phys., 2007, 9, 982-990. (45) Holloczki

Communication: The absolute shielding scales of oxygen and sulfur revisited

Energy Technology Data Exchange (ETDEWEB)

Komorovsky, Stanislav; Repisky, Michal; Malkin, Elena; Ruud, Kenneth, E-mail: kenneth.ruud@uit.no [Centre for Theoretical and Computational Chemistry, University of Tromsø — The Arctic University of Norway, N-9037 Tromsø (Norway); Gauss, Jürgen [Institut für Physikalische Chemie, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, D-55128 Mainz (Germany)

2015-03-07

We present an updated semi-experimental absolute shielding scale for the {sup 17}O and {sup 33}S nuclei. These new shielding scales are based on accurate rotational microwave data for the spin–rotation constants of H{sub 2}{sup 17}O [Puzzarini et al., J. Chem. Phys. 131, 234304 (2009)], C{sup 17}O [Cazzoli et al., Phys. Chem. Chem. Phys. 4, 3575 (2002)], and H{sub 2}{sup 33}S [Helgaker et al., J. Chem. Phys. 139, 244308 (2013)] corrected both for vibrational and temperature effects estimated at the CCSD(T) level of theory as well as for the relativistic corrections to the relation between the spin–rotation constant and the absolute shielding constant. Our best estimate for the oxygen shielding constants of H{sub 2}{sup 17}O is 328.4(3) ppm and for C{sup 17}O −59.05(59) ppm. The relativistic correction for the sulfur shielding of H{sub 2}{sup 33}S amounts to 3.3%, and the new sulfur shielding constant for this molecule is 742.9(4.6) ppm.

WRF-Chem model predictions of the regional impacts of N2O5 heterogeneous processes on night-time chemistry over north-western Europe

Directory of Open Access Journals (Sweden)

D. Lowe

2015-02-01

Full Text Available Chemical modelling studies have been conducted over north-western Europe in summer conditions, showing that night-time dinitrogen pentoxide (N2O5 heterogeneous reactive uptake is important regionally in modulating particulate nitrate and has a~modest influence on oxidative chemistry. Results from Weather Research and Forecasting model with Chemistry (WRF-Chem model simulations, run with a detailed volatile organic compound (VOC gas-phase chemistry scheme and the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC sectional aerosol scheme, were compared with a series of airborne gas and particulate measurements made over the UK in July 2010. Modelled mixing ratios of key gas-phase species were reasonably accurate (correlations with measurements of 0.7–0.9 for NO2 and O3. However modelled loadings of particulate species were less accurate (correlation with measurements for particulate sulfate and ammonium were between 0.0 and 0.6. Sulfate mass loadings were particularly low (modelled means of 0.5–0.7 μg kg−1air, compared with measurements of 1.0–1.5 μg kg−1air. Two flights from the campaign were used as test cases – one with low relative humidity (RH (60–70%, the other with high RH (80–90%. N2O5 heterogeneous chemistry was found to not be important in the low-RH test case; but in the high-RH test case it had a strong effect and significantly improved the agreement between modelled and measured NO3 and N2O5. When the model failed to capture atmospheric RH correctly, the modelled NO3 and N2O5 mixing ratios for these flights differed significantly from the measurements. This demonstrates that, for regional modelling which involves heterogeneous processes, it is essential to capture the ambient temperature and water vapour profiles. The night-time NO3 oxidation of VOCs across the whole region was found to be 100–300 times slower than the daytime OH oxidation of these compounds. The difference in contribution was less

Dioxobridged complexes of molybdenum (IV) and tungsten (IV) with ...

Indian Academy of Sciences (India)

Unknown

Acknowledgement. We thank Rhone Poulenc, Paris, France for supplying MPM and M/s Bayer A G,. Leverkusen, Germany for providing PCPD and TFPH as gift samples. References. 1. Hewitt E J 1959 Biol. Rev. 34 333. 2. Kay A and Mitchell P C H 1970 J. Chem. Soc. A 2421. 3. Russell Melby L 1969 Inorg. Chem. 8 1539.

Urea/thiourea derivatives and Zn(II)-DPA complex as receptors for ...

Indian Academy of Sciences (India)

of industries related to agricultural fertilizers, food additives and water. Along with these, recent emphasis on environmental concern — both industrially and ...... Tocci G M, Kruger P E and Pfeffer F M 2006 Coord. Chem. Rev. 250 3094; (p) Filby M H and Steed J W 2006. Coord. Chem. Rev. 250 3200; (q) O'Neil E J and ...

Rapid Synthesis of 2-Substituted-2,3-dihydro-4(1H)-quinazolinones ...

African Journals Online (AJOL)

NICO

dron Lett., 2003, 44, 6153. 26 C. Mukhopadhyay, A. Datta and R.J. Butcher, Tetrahedron Lett., 2009,. 50, 4246. 27 G. Harichandran, S.D. Amalraj and P. Shanmugam, J. Iran. Chem. Soc.,. 2011, 8, 298. 28 M. Wang, T.T. Zhang and Z.G. Song, Chin. Chem. Lett., 2011, 22, 427. RESEARCH ARTICLE. Z. Karimi-Jaberi and L.

Reply to the Comment by A. Wyttenbach and L. Tobler and correction for errata on 'Minor and trace element determination of food spices and pulses of different origins by NAA and PAA'

International Nuclear Information System (INIS)

Miyamoto, Y.; Kajikawa, A.; Zaidi, J.H.; Nakanishi, T.; Sakamoto, K.; Kanazawa Univ.

2001-01-01

Reply is given to the comment by A. Wyttenbach and L. Tobler in J. Radioanal. Nucl. Chem., 247 (2001) 457 on the article by Y. Miyamoto et. al. published in J. Radioanal. Nucl. Chem. 243 (2000) 747 on 'Minor and trace element determination of food spices and pulses of different origins by NAA and PAA'. (N.T.)

Untitled

Indian Academy of Sciences (India)

Pfeifer, V. F. Vognovich, C. ... “Vitamin Bls by fermentation with Streptomyces olivaceus,” and Heger, E. N. Ind. Eng. Chem., 1954, 46, 843; Rev. Chem, and Eng. News, 1949, 27, 2848. Rice, T. R. ... “Biotic influences effecting population growth of planktonic algae,” U.S. Wild Life Service Bull, 1954, 54 (87), 227–45. Saunders ...

Research and Teaching: Transforming Discussion in General Chemistry with Authentic Experiences for Engineering Students

Science.gov (United States)

Crippen, Kent J.; Boyer, Treavor H.; Korolev, Maria; de Torres, Trisha; Brucat, Phil J.; Wu, Chang-Yu

2016-01-01

Undergraduate engineering education in the United States is in need of reform that addresses the recruitment and retention of a diverse population of students. Change Chem is a curriculum reform model that has been created to address this issue for freshman students. This article reports on a mixed method efficacy study of Change Chem, which uses…

Self-assembly of a Co(II) dimer through H-bonding of water ...

Indian Academy of Sciences (India)

Unknown

more ligands are used, the design and choice of the components must fulfill criteria for spontaneously generating well-defined architectures. Much of the current effort ..... C S, Son S K, Lee Y S, Jun M J and Do Y 1999. Inorg. Chem. 38 5602. 16. Subramaniam S and Zaworotko M J 1995 Angew. Chem., Int. Ed. Engl. 34 2127.

Molecular Engineering of Liquid Crystalline Polymers

Science.gov (United States)

1992-03-27

Szasz , N. Sheppard and D. H. Rank, J. Chem. Phys., 1948, 16..704 119. P. B. Woller and E. W. Garbisch, Jr., J. Am. Chem. Soc., 1972, 94, 53 10 120. A. L...schematic representation of a sanidic (from Greek for boardlike) mesophase.202 Figure 15. a) Layer spacing d calculated according to Bragg’s law

antimycobacterial and cytotoxicity evaluation of the constituents of ...

African Journals Online (AJOL)

nb

AKT/mTOR pathway and S phase cell cycle arrest in HepG2 cells. Food. Chem. 138: 1034-1041. Chen T, He J, Zhang J, Li X, Zhang H, Hao. J, Li L 2012 The isolation and identification of two compounds with predominant radical scavenging activity in hempseed (seed of Cannabis sativa. L.). Food Chem. 134: 1030-1037.

Automatic vs. manual curation of a multi-source chemical dictionary: the impact on text mining

Science.gov (United States)

2010-01-01

Background Previously, we developed a combined dictionary dubbed Chemlist for the identification of small molecules and drugs in text based on a number of publicly available databases and tested it on an annotated corpus. To achieve an acceptable recall and precision we used a number of automatic and semi-automatic processing steps together with disambiguation rules. However, it remained to be investigated which impact an extensive manual curation of a multi-source chemical dictionary would have on chemical term identification in text. ChemSpider is a chemical database that has undergone extensive manual curation aimed at establishing valid chemical name-to-structure relationships. Results We acquired the component of ChemSpider containing only manually curated names and synonyms. Rule-based term filtering, semi-automatic manual curation, and disambiguation rules were applied. We tested the dictionary from ChemSpider on an annotated corpus and compared the results with those for the Chemlist dictionary. The ChemSpider dictionary of ca. 80 k names was only a 1/3 to a 1/4 the size of Chemlist at around 300 k. The ChemSpider dictionary had a precision of 0.43 and a recall of 0.19 before the application of filtering and disambiguation and a precision of 0.87 and a recall of 0.19 after filtering and disambiguation. The Chemlist dictionary had a precision of 0.20 and a recall of 0.47 before the application of filtering and disambiguation and a precision of 0.67 and a recall of 0.40 after filtering and disambiguation. Conclusions We conclude the following: (1) The ChemSpider dictionary achieved the best precision but the Chemlist dictionary had a higher recall and the best F-score; (2) Rule-based filtering and disambiguation is necessary to achieve a high precision for both the automatically generated and the manually curated dictionary. ChemSpider is available as a web service at http://www.chemspider.com/ and the Chemlist dictionary is freely available as an XML file in

Comparison of the applicability of commercial computer programs to study the thermodynamic stability of metal oxides

International Nuclear Information System (INIS)

Koukkari, P.; Olin, M.; Laitinen, T.; Sippola, H.

1999-04-01

The oxide films formed on primary circuit surfaces incorporate radioactive species from the coolant and influence different corrosion phenomena in nuclear power plants. One approach to improve the understanding on the formation and properties of these oxide films is to evaluate their thermodynamic stability. The aim of this work was to compare and demonstrate the applicability of different commercial thermodynamic computer programs to model the deposition of oxides containing iron, chromium and/or nickel in various nuclear power plant environments. The programs considered in this evaluation comprised the EQ3/6 program and a product group including such products as ChemSage, HSC (including SOLGASMIX and GIBBS), H+PLUS and ChemSheet. In the group the transfer of data between different products is relatively easy. The goal was to find out which programs can be applied to evaluate the stability of oxide films, but not to assess the absolute accuracy of the calculations. The evaluation was done by means of applying the programs to calculate the stability of pure and mixed oxides of iron, nickel and chromium on stainless steel both in WWER and BWR conditions at different temperatures and coolant compositions. The comparison showed that EQ3/6 is suitable for most thermodynamic calculations. EQ3/6 can be characterised as a professional tool, for which no commercial training is available. ChemSage is a versatile and reliable program, which can be well used together with HSC and H+PLUS. ChemSage is mainly a professional tool, while HSC is easier to operate by an occasional user. Commercial training and support is available for both ChemSage and HSC. ChemSheet has been designed to utilise the properties of ChemSage in a user-friendly spreadsheet environment. All the products tested calculate thermodynamic equilibrium. Thus they are suitable to characterise such conditions in which the formation of a certain phase is or becomes possible. On the other hand, the modelling of the

Comparison of the applicability of commercial computer programs to study the thermodynamic stability of metal oxides; Vertailu kaupallisten laskentaohjelmien soveltuvuudesta metallioksidien termodynaamiseen stabiilisuustarkasteluun

Energy Technology Data Exchange (ETDEWEB)

Koukkari, P.; Olin, M. [VTT Chemical Technology, Espoo (Finland); Laitinen, T. [VTT Manufacturing Technology, Espoo (Finland); Sippola, H. [GEM Systems Oy (Finland)

1999-04-01

The oxide films formed on primary circuit surfaces incorporate radioactive species from the coolant and influence different corrosion phenomena in nuclear power plants. One approach to improve the understanding on the formation and properties of these oxide films is to evaluate their thermodynamic stability. The aim of this work was to compare and demonstrate the applicability of different commercial thermodynamic computer programs to model the deposition of oxides containing iron, chromium and/or nickel in various nuclear power plant environments. The programs considered in this evaluation comprised the EQ3/6 program and a product group including such products as ChemSage, HSC (including SOLGASMIX and GIBBS), H+PLUS and ChemSheet. In the group the transfer of data between different products is relatively easy. The goal was to find out which programs can be applied to evaluate the stability of oxide films, but not to assess the absolute accuracy of the calculations. The evaluation was done by means of applying the programs to calculate the stability of pure and mixed oxides of iron, nickel and chromium on stainless steel both in WWER and BWR conditions at different temperatures and coolant compositions. The comparison showed that EQ3/6 is suitable for most thermodynamic calculations. EQ3/6 can be characterised as a professional tool, for which no commercial training is available. ChemSage is a versatile and reliable program, which can be well used together with HSC and H+PLUS. ChemSage is mainly a professional tool, while HSC is easier to operate by an occasional user. Commercial training and support is available for both ChemSage and HSC. ChemSheet has been designed to utilise the properties of ChemSage in a user-friendly spreadsheet environment. All the products tested calculate thermodynamic equilibrium. Thus they are suitable to characterise such conditions in which the formation of a certain phase is or becomes possible. On the other hand, the modelling of the

ChemSearch Journal - Vol 7, No 2 (2016)

African Journals Online (AJOL)

Quantitative analysis of caffeine in some selected brands of energy drinks available in Kano State Nigeria · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. M.I. Mohammed, J Abdulrauf, A.S. Bayero, 24-27 ...

Chem I Supplement: Liquid Crystals--The Chameleon Chemicals.

Science.gov (United States)

Brown, Glenn H.

1983-01-01

Presents information relevant to everyday life so as to stimulate student interest in the properties of the two basic types of liquid crystals: thermotropic and lyotropic. Describes the applications of liquid crystals to electronics, biomedicine, and polymer science and appraises the future of liquid crystal research. (JM)

Blending Chem-Bio Dispersion Forecasts and Sensor Data

Science.gov (United States)

2008-12-31

Kerrie Long. 5d. PROJECT NUMBER N/A 5e. TASK NUMBER N/A 5f. WORK UNIT NUMBER N/A 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) CUBRC ...Acknowlegments I gratefully acknowledge the efforts of the team of faculty, consultants and graduate students from CUBRC , the University at Buffalo, the...Moskal, CUBRC Alex James, CUBRC 3.5 Graduate Students Umamaheswara Reddy, Dept. Mechanical Engineering, University at Buffalo Gabriel Terejanu

ChemSearch Journal - Vol 5, No 2 (2014)

African Journals Online (AJOL)

Bipyridinium Tetrachloronickelate (II) and 4,4′-Bipyridine Dichloronickel (II) Complexes · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. MA Kurawa, SG Yammama, 59-65 ...

I:\\AA-TYPESET\\CHEM\\2006\\Van Es.vp

African Journals Online (AJOL)

NJD

aDepartment of Biochemistry and Microbiology, Cook College, Rutgers, The State University of New Jersey, 08903-0231, USA. bSchool of Chemistry, University of the Witwatersrand, Johannesburg, South Africa. cVisiting Associate, Department of Chemistry and Biomolecular Sciences, Macquarie University, NSW 2109, ...

A water soluble heteropolyoxotungstate as a selective, efficient and ...

Indian Academy of Sciences (India)

Administrator

In the catalytic system described here product isolation is easy, and the aqueous catalyst solution can be re-used several times with little loss in ... tle loss in the total amount of the heavy metal, which makes the overall process green ..... Chem. Res. 27 387. 12. Waters T, O'Hair R A J and Wedd A G 2003 J. Am. Chem. Soc.

The Use of Optical Electronegativities to Assign Electronic Spectra of Semiquinone Complexes

Science.gov (United States)

1990-08-03

Auburn, E.S. Dodsworth, M. Haga, W. Liu, M. Melnik and W.A. Nevin, J. Am. Chem. Soc. 110 (1988) 8076. 8. C. Benelli, A. Dei, D. Gatteschi and L. Pardi...Inorg. Chim. Acta 163 (1989) 99. 9. C. Benelli, A. Dei, D. Gatteschi and L. Pardi, Inorg. Chem. 28 (1989) 1476. 10. C. Benelli, A. Dei, D. Gatteschi , H.U

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African Journals Online (AJOL)

J.R. Hall, B.F. Wishaw and R.H. Stokes, J. Am. Chem. Soc., 75, 1556 (1963). M.F. Zaranyika, P. Moses and T. Mavunganidze, J. Polym. Science: Part. A: Polym. Chem., 28, 3565 (1990). 6. R.D. Kremer and D. Tabb, Intern. Lab. 19, 40 (1989). 7. S.N. Vinogradov and R.H. Linnell, "Hydrogen Bonding", Van Nostrand, N.Y.,.

trisubstituted imidazoles by using microwave irradiation under

Indian Academy of Sciences (India)

Administrator

Catal. A: Chem. 265 177. 45. Khosropour A R 2008 Ultrason. Sonochem. 15 659. 46. Sharma S D, Hazarika P and Konwar D 2008 Tetra- hedron Lett. 49 2216. 47. Heravi M M, Sadjadi S, Oskooie H A, Hekmatshoar. R and Bamoharram F F 2008 J. Chin. Chem. Soc. 55. 1199. 48. Sangshetti J N, Shinde D B, Kokare N D and.

Untitled

Indian Academy of Sciences (India)

Gouterman M. 1978 in The porphyrins (ed.) D Dolphin (New York: Academic Press) vol.3, pp. 157–231. Gouterman M, Schwarz F P, Smith PD and Dolphin D 1973 J. Chem. Phys. 59 676. Merkel P. P and Kearns D R 1972 J. Am. Chem. Soc. 94 7241. Norris Jr J R and Meiser D (eds) 1989 Photochemical emergy conversion ...

Synthesis, crystal structure, thermal analysis and dielectric ...

Indian Academy of Sciences (India)

[13] Perry C H and Lowdes R P 1969 J. Chem. Phys. 51 3648. [14] Sheldrick G M 1997 SHELXS9, Program for the Refinement of Crystal Structures (Germany: University of Gottingen). [15] Loukil M, Kabadou A, Salles Ph and Ben Salah A 2004 Chem. Phys. 300 247. [16] Rolies M M and De Ranter C J 1978 Acta Crystallogr.

Self-assembly of self-assembled molecular triangles

Indian Academy of Sciences (India)

SB/S1/IC-05/2014) for providing financial support to our research endeav- ours. We gratefully acknowledge the single crystal X- ray diffractometer facility funded by IIT Madras. References. 1. (a) Cook T R, Zheng Y-R and Stang P J 2013 Chem. Rev. 113 734; (b) Debata N B, Tripathy D and Chand. D K 2012 Coord. Chem.

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

OpenAIRE

Ibrić Svetlana; Đurić Zorica; Parojčić Jelena; Petrović Jelena

2011-01-01

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, someon...

On the use temperature parameterized rate coefficients in the estimation of non-equilibrium reaction rates

Science.gov (United States)

Shizgal, Bernie D.; Chikhaoui, Aziz

2006-06-01

The present paper considers a detailed analysis of the nonequilibrium effects for a model reactive system with the Chapman-Eskog (CE) solution of the Boltzmann equation as well as an explicit time dependent solution. The elastic cross sections employed are a hard sphere cross section and the Maxwell molecule cross section. Reactive cross sections which model reactions with and without activation energy are used. A detailed comparison is carried out with these solutions of the Boltzmann equation and the approximation introduced by Cukrowski and coworkers [J. Chem. Phys. 97 (1992) 9086; Chem. Phys. 89 (1992) 159; Physica A 188 (1992) 344; Chem. Phys. Lett. A 297 (1998) 402; Physica A 275 (2000) 134; Chem. Phys. Lett. 341 (2001) 585; Acta Phys. Polonica B 334 (2003) 3607.] based on the temperature of the reactive particles. We show that the Cukrowski approximation has limited applicability for the large class of reactive systems studied in this paper. The explicit time dependent solutions of the Boltzmann equation demonstrate that the CE approach is valid only for very slow reactions for which the corrections to the equilibrium rate coefficient are very small.

Untitled

Indian Academy of Sciences (India)

Frein, M. L., and Fisher, C. H. ... Ind. and Eng. Chen, 1948, 40, 534. 2. Kosolapoff, G. M. ... J. Amer. Chem. Soc., 1947, 69, 1651. 3. Fornet, R, ... Seifensieder-2tg., 1938, 65, 658 and 687. 4. Dusart, L, and Bardy, Ch. ... Compt, rend, 73, 1276. 5. Gal, H., and Etard, A. ... Ibid., 82, 457. 6. Demole, E. ... Deut. Chem. Ges, Ber, 1877 ...

Growth of CdS nanoparticles by chemical method and its ...

Indian Academy of Sciences (India)

carbon film supported on the copper grid and was kept for some time for drying. Transmission electron ... Wang et al obtained CdS nanoparticles having a band gap of. 2.79 eV [21]. .... [16] S Yu, Y Wu, J Yang, Z Han, Y Quan, X Liu and Y Xie, Chem. Matter 10 ... [22] U K Gautam, R Seshadri and C N R Rao, Chem. Phys. Lett.

Studies towards C-3 functionalization of β-lactams using substituted ...

Indian Academy of Sciences (India)

β-lactams using substituted allylsilanes. 1753. 2. Mascaretti O A, Boschetti C E, Danelon G O, Mata E G and Roveri O A 1995 Current Med. Chem. 1 441. 3. Hatanaka N, Abe R and Ojima I 1981 Chem. Lett. 10 1297. 4. O'Boyle N, Carr M, Greene L, Bergin O, Nathwani S,. McCabe T, Lloyd D, Zisterer D and Meegan M 2010.

Alloactinosynnema iranicum sp. nov., a rare actinomycete isolated from a hypersaline wetland, and emended description of the genus Alloactinosynnema.

Science.gov (United States)

Nikou, Mahdi Moshtaghi; Ramezani, Mohaddaseh; Amoozegar, Mohammad Ali; Fazeli, Seyed Abolhassan Shahzadeh; Schumann, Peter; Spröer, Cathrin; Sánchez-Porro, Cristina; Ventosa, Antonio

2014-04-01

A Gram-staining-positive actinobacterial strain, Chem10(T), was isolated from soil around Inche-Broun hypersaline wetland in the north of Iran. Strain Chem10(T) was strictly aerobic, and catalase- and oxidase-positive. The isolate grew with 0-3 % NaCl, at 20-40 °C and at pH 6.0-8.0. The optimum temperature and pH for growth were 30 °C and pH 7.0, respectively. The cell wall of strain Chem10(T) contained meso-diaminopimelic acid as diamino acid and galactose, ribose and arabinose as whole-cell sugars. The polar lipid pattern contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Strain Chem10(T) synthesized cellular fatty acids of the straight-chain saturated and mono-unsaturated, and iso- and anteiso-branched types C14 : 0, C16 : 0, iso-C16 : 1, anteiso-C17 : 0, iso-C16 : 0, iso-C14 : 0 and iso-C15 : 0, and the major respiratory quinone was MK-9(H4). The G+C content of the genomic DNA was 70.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Chem10(T) belonged to the family Pseudonocardiaceae and showed the closest phylogenetic similarity to Alloactinosynnema album KCTC 19294(T) (98.3 %) and Actinokineospora cibodasensis DSM 45658(T) (97.9 %). DNA-DNA relatedness values between the novel strain and strains Alloactinosynnema album KCTC 19294(T) and Actinokineospora cibodasensis DSM 45658(T) were only 52 % and 23 %, respectively. On the basis of phylogenetic analysis, phenotypic characteristics and DNA-DNA hybridization data, a novel species of the genus Alloactinosynnema is proposed, Alloactinosynnema iranicum sp. nov. The type strain is Chem10(T) ( = IBRC-M 10403(T) = CECT 8209(T)). In addition, an emended description of the genus Alloactinosynnema is proposed.

Chemical Technology Division progress report for the period April 1, 1985 to December 31, 1986

International Nuclear Information System (INIS)

1987-08-01

This progress report summarizes the research and development efforts conducted in the Chemical Technology Division (Chem Tech) during the period April 1, 1985, through December 31, 1986. The following major areas are covered in the discussion: nuclear and chemical waste management, environmental control technology, basic science and technology, biotechnology research, transuranium-element processing, Nuclear Regulatory Commission programs, radioactive materials production, computer/engineering applications, fission energy, environmental cleanup projects, and various other work activities. As an appendix, the Administrative Summary presents a comprehensive compilation of publications, oral presentations, awards and recognitions, and patents of Chem Tech staff members during this report period. An organization chart, a staffing level and financial summary, and lists of seminars and Chem Tech consultants for the period are also included to provide additional information. 78 figs., 40 tabs

Chemical Technology Division progress report for the period April 1, 1985 to December 31, 1986

Energy Technology Data Exchange (ETDEWEB)

1987-08-01

This progress report summarizes the research and development efforts conducted in the Chemical Technology Division (Chem Tech) during the period April 1, 1985, through December 31, 1986. The following major areas are covered in the discussion: nuclear and chemical waste management, environmental control technology, basic science and technology, biotechnology research, transuranium-element processing, Nuclear Regulatory Commission programs, radioactive materials production, computer/engineering applications, fission energy, environmental cleanup projects, and various other work activities. As an appendix, the Administrative Summary presents a comprehensive compilation of publications, oral presentations, awards and recognitions, and patents of Chem Tech staff members during this report period. An organization chart, a staffing level and financial summary, and lists of seminars and Chem Tech consultants for the period are also included to provide additional information. 78 figs., 40 tabs.

Effect of chemically and biologically synthesized Ag nanoparticles on the algae growth inhibition

Science.gov (United States)

Anna, Mražiková; Oksana, Velgosová; Jana, Kavuličová

2017-12-01

Over the past few years green methods for preparation of silver nanoparticles has become necessary due to its friendly influence on ecosystem. In the present work antimicrobial properties of biologically synthesized silver nanoparticles (Bio-AgNPs) using green algae extract and chemically synthesized silver nanoparticles (Chem-AgNPs) using sodium citrate against algae Parachlorella kessleri is investigated. Both used Bio-AgNPs and Chem-AgNPs exhibit long-term stability as demonstrated by UV-vis spectroscopy measurements. The results revealed stronger toxic effects of Bio-AgNPs on agar plates what was confirmed clear inhibition zone around wells impregnated with Bio-AgNPs. On the other hand Bio-AgNPs were confirmed to be less toxic in aquatic environments for the growths of green algae P. kessleri comparing to Chem-AgNPs.

Asymmetrically doped one-dimensional trans-polymers

International Nuclear Information System (INIS)

Caldas, Heron

2009-01-01

More than 30 years ago [H. Shirakawa, E.J. Louis, A.G. MacDiarmid, C.K. Chiang, A.J. Heeger, J. Chem. Soc. Chem. Comm. 578 (1977); S. Etemad, A.J. Heeger, Ann. Rev. Phys. Chem. 33 (1982) 443] it was discovered that doped trans-polyacetylene (CH) x , a one-dimensional (1D) conjugated polymer, exhibits electrical conductivity. In this work we show that an asymmetrically doped 1D trans-polymer has non-conventional properties, as compared to symmetrically doped systems. Depending on the level of asymmetry between the chemical potentials of the two involved fermionic species, the polymer can be in a partially or fully spin polarized state. Some possible experimental consequences of doped 1D trans-polymers used as 1D organic polarized conductors are discussed.

Fulltext PDF

Indian Academy of Sciences (India)

TECS

(a) Gearheart L A, Somoza M M, Rivers W E, Mur- phy C J, Coleman R S and Berg M A 2003 J. Am. Chem. Soc. 125 11812; (b) Brauns E B, Madaras M. L, Coleman R S and Berg M A 2002 Phys. Rev. Lett. 88 158101-1-4. 19. Frauchiger L, Shirota H, Uhrich K E and Castner E. W Jr 2002 J. Phys. Chem. B106 7463. 20.

Artificial Photosynthesis: Beyond Mimicking Nature

International Nuclear Information System (INIS)

Dau, Holger; Fujita, Etsuko; Sun, Licheng

2017-01-01

In this Editorial, Guest Editors Holger Dau, Etsuko Fujita, and Licheng Sun introduce the Special Issue of ChemSusChem on “Artificial Photosynthesis for Sustainable Fuels”. Here, they discuss the need for non-fossil based fuels, introduce both biological and artificial photosynthesis, and outline various important concepts in artificial photosynthesis, including molecular and solid-state catalysts for water oxidation and hydrogen evolution, catalytic CO 2 reduction, and photoelectrochemical systems.

Excess molar volumes and viscosities of binary mixtures of some ...

Indian Academy of Sciences (India)

Unknown

... H T S, Aralaguppi M I and. Hansen K C 1994 J. Chem. Eng. Data 39 251. 43. Pal A and Kumar H 2001 Fluid Phase Equilibria 181 17. 44. Reed T M III and Taylor T E 1959 J. Phys. Chem. 63 58. 45. Meyer R, Meyer J, Metzer J and Peneloux A 1971 J. Chim. Phys. 68 406. 46. Palepu R, Oliver J and Mackinnon B 1985 Can.

NSSEFF COMPUTATIONAL AND THEORETICAL DESIGN OF PHOTO AND MECHANORESPONSIVE MOLECULAR DEVICES

Science.gov (United States)

2016-11-10

piston ). Once we discovered reactions in this way, we realized that the reactions could then be studied with...Cluster Singles and Doubles via Tensor Hypercontraction: THC-CC2," J. Chem. Phys. 138, 124111 (2013). 26. E.G. Hohenstein, S.I.L. Kokkila, R.M...Singles and Doubles via Orbital-Weighted Least-Squares Tensor Hypercontraction," J. Chem. Phys. 140, 181102 (2014). 29. R.M. Parrish, E.G.

Exploring the High-Pressure Behavior of PETN: A Combined Quantum Mechanical and Experimental Study

Science.gov (United States)

2006-11-01

calculations to explore the hypothesized compression-induced polymorphic phase transition [Gruzdkov 2004]. The initial crystal in these Figure 4...Scuseria, G.E., and Chabalowski, C.F. 2004: An ab Initio Study of Solid Nitromethane, HMX , RDX , and CL20: Successes and Failures of DFT. J. Phys. Chem... RDX , HMX , HNIW, and PETN Crystals. J. Phys. Chem. B, 103, 6783. Trotter, J., 1963: Bond lengths and angles in Pentaerythritol Tetranitrate. Acta

Synthesis of cyano-bridged bimetallic complexes of η5 -indenyl ...

Indian Academy of Sciences (India)

Unknown

Gamasa P M, Gimino J, Bernado C G and Martin-Vaca B M 1996 Organometallics 15 302. 15. Oro L A, Ciriano M A and Campo M 1985 J. Organomet. Chem. 289 117. 16. Bennet M A, Huang T N, Matheson T W and Smith A K 1982 Inorg. Syn. 21 74. 17. Blackmore T, Bruce M I and Stone F G A 1971 J. Chem. Soc. A 2376.

Symposium on Molecular Spectroscopy (39th) Held in Columbus, Ohio on 11-15 Jun 84.

Science.gov (United States)

1984-06-15

02139; R. BACIS, and S. CHURASSY, Laboratoire de Spectrometrie lonique et Moleculaire, Universit Claude Bernard (Lvon 1), 69622 Villeurbanne, France. r...Spectrometrie * lonique et Moleculaire, Universite Claude Bernard -Lyon I, 69622 Villeurbanne, - France; C. LINTON, Department of Physics, University of New...National Bureau of Standards. 3. S. Muenter and W. Klemperer, J. Chem. Phys. 52, 6033 (1970). 20. K. Hindermann and C. D. Cornwell , J. Chem. Ph-ys. 48

Microstructure analysis of chemically synthesized wurtzite-type CdS ...

Indian Academy of Sciences (India)

37, 4682 (1998). [12] O Z Angel and R L Morales, Phys. Rev. B 62, 13064 (2000). [13] S Wei and S B Zhang, Phys. Rev. B 62, 6944 (2000). [14] G Lin, J Zheng and R Xu, J. Phy. Chem. C 112, 7363 (2008). [15] N Bao, L Shen, T Takata, K Domen, A Gupta, K Yanagisawa and C A Grimes, J. Phys. Chem. C 111, 17527 (2007).

(nitro substituted-phenyl)-hydrazonomethyl

Indian Academy of Sciences (India)

7.14 (d, 1H, ArH), δ 7.36 (m, 2H, ArH), δ 7.47–7.51 (m,. 2H, ArH), δ 7.77 ..... Phys. Chem. A 115 1985; (d) Kang Y, Gwon K, Shin J H, ... (a) Zhang J F, Lim C S, Bhuniya S, Cho B R and Kim. J S 2011 Org. ... Chem. Rev. 240 1; (c) Sessler J L and.

Corrigendum to "A novel downscaling technique for the linkage of global and regional air quality modeling" published in Atmos. Chem. Phys., 9, 9169–9185, 2009

Directory of Open Access Journals (Sweden)

Y. F. Lam

2010-04-01

Full Text Available Recently, downscaling global atmospheric model outputs (GCTM for the USEPA Community Multiscale Air Quality (CMAQ Initial (IC and Boundary Conditions (BC have become practical because of the rapid growth of computational technologies that allow global simulations to be completed within a reasonable time. The traditional method of generating IC/BC by profile data has lost its advocates due to the weakness of the limited horizontal and vertical variations found on the gridded boundary layers. Theoretically, high quality GCTM IC/BC should yield a better result in CMAQ. Unfortunately, several researchers have found that the outputs from GCTM IC/BC are not necessarily better than profile IC/BC due to the excessive transport of O₃ aloft in GCTM IC/BC. In this paper, we intend to investigate the effects of using profile IC/BC and global atmospheric model data. In addition, we are suggesting a novel approach to resolve the existing issue in downscaling.

In the study, we utilized the GEOS-Chem model outputs to generate time-varied and layer-varied IC/BC for year 2002 with the implementation of tropopause determining algorithm in the downscaling process (i.e., based on chemical (O₃ tropopause definition. The comparison between the implemented tropopause approach and the profile IC/BC approach is performed to demonstrate improvement of considering tropopause. It is observed that without using tropopause information in the downscaling process, unrealistic O₃ concentrations are created at the upper layers of IC/BC. This phenomenon has caused over-prediction of surface O₃ in CMAQ. In addition, the amount of over-prediction is greatly affected by temperature and latitudinal location of the study domain. With the implementation of the algorithm, we have successfully resolved the incompatibility issues in the vertical layer structure between global and regional chemistry models to yield better surface O₃