Science.gov

Sample records for 10-4 mol dm-3

  1. Effect of cationic molecules on the oxygen reduction reaction on fuel cell grade Pt/C (20 wt%) catalyst in potassium hydroxide (aq, 1 mol dm(-3)).

    PubMed

    Ong, Ai Lien; Inglis, Kenneth K; Whelligan, Daniel K; Murphy, Sam; Varcoe, John R

    2015-05-14

    This study investigates the effect of 1 mmol dm(-3) concentrations of a selection of small cationic molecules on the performance of a fuel cell grade oxygen reduction reaction (ORR) catalyst (Johnson Matthey HiSPEC 3000, 20 mass% Pt/C) in aqueous KOH (1 mol dm(-3)). The cationic molecules studied include quaternary ammonium (including those based on bicyclic systems) and imidazolium types as well as a phosphonium example: these serve as fully solubilised models for the commonly encountered head-groups in alkaline anion-exchange membranes (AAEM) and anion-exchange ionomers (AEI) that are being developed for application in alkaline polymer electrolyte fuel cells (APEFCs), batteries and electrolysers. Both cyclic and hydrodynamic linear sweep rotating disk electrode voltammetry techniques were used. The resulting voltammograms and subsequently derived data (e.g. apparent electrochemical active surface areas, Tafel plots, and number of [reduction] electrons transferred per O2) were compared. The results show that the imidazolium examples produced the highest level of interference towards the ORR on the Pt/C catalyst under the experimental conditions used.

  2. A Potentiometric, Spectrophotometric and Pitzer Ion-Interaction Study of Reaction Equilibria in the Aqueous H+-Al3+, H+-Oxalate and H+-Al3+-Oxalate Systems up to 5 mol*dm-3 NaCl

    SciTech Connect

    Boily, Jean F.; Qafoku, Odeta; Felmy, Andrew R.

    2007-12-01

    Aluminium-oxalate complexation was determined in acidic media of aqueous NaCl solutions ranging from 0.1-5.0 mol•dm-3. Complexation in the H+-Al3+ and H+-Oxalate systems was also studied to provide a set of internally consistent thermodynamic data. The ionic strength dependent formation constants describing the stabilities of the Al3+, AlOH2+, Al3(OH)45+, Al13O4(OH)247+, H2L, HL-, L2-, AlL+, AlL2- and AlL33- species (where L is the oxalate ion) was also described using a Pitzer ion interaction model. The derived parameters can be used to predict chemical speciation in the H+-Al3+-Oxalate system in the 0.1-5.0 mol•dm-3 NaCl range.

  3. 27 CFR 10.4 - Jurisdictional limits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Jurisdictional limits. 10.4 Section 10.4 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS COMMERCIAL BRIBERY Scope of Regulations § 10.4 Jurisdictional limits....

  4. MolView users guide

    SciTech Connect

    Walenz, B.P.

    1996-06-01

    A system for viewing molecular data in a CAVE virtual reality environment is presented. The system, called MolView, consists of a frontend driver program that prepares the data and a backend CAVE program that displays the data. Both are written so that modifications and extensions are relatively easy to accomplish.

  5. 24 CFR 10.4 - Rules docket.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Rules docket. 10.4 Section 10.4 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development... Housing and Urban Development, 451 7th Street, SW., Washington, DC 20410. All public rulemaking...

  6. 10 CFR 10.4 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Policy. 10.4 Section 10.4 Energy NUCLEAR REGULATORY COMMISSION CRITERIA AND PROCEDURES FOR DETERMINING ELIGIBILITY FOR ACCESS TO RESTRICTED DATA OR NATIONAL... Nuclear Regulatory Commission to carry out its responsibility for the security of the nuclear...

  7. 27 CFR 10.4 - Jurisdictional limits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Jurisdictional limits. 10.4 Section 10.4 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... direct effect of the inducement is to prevent, deter, hinder, or restrict other persons from selling...

  8. 10 CFR 10.4 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Policy. 10.4 Section 10.4 Energy NUCLEAR REGULATORY COMMISSION CRITERIA AND PROCEDURES FOR DETERMINING ELIGIBILITY FOR ACCESS TO RESTRICTED DATA OR NATIONAL... Nuclear Regulatory Commission to carry out its responsibility for the security of the nuclear...

  9. 10 CFR 10.4 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Policy. 10.4 Section 10.4 Energy NUCLEAR REGULATORY COMMISSION CRITERIA AND PROCEDURES FOR DETERMINING ELIGIBILITY FOR ACCESS TO RESTRICTED DATA OR NATIONAL... Nuclear Regulatory Commission to carry out its responsibility for the security of the nuclear...

  10. 10 CFR 10.4 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Policy. 10.4 Section 10.4 Energy NUCLEAR REGULATORY COMMISSION CRITERIA AND PROCEDURES FOR DETERMINING ELIGIBILITY FOR ACCESS TO RESTRICTED DATA OR NATIONAL... Nuclear Regulatory Commission to carry out its responsibility for the security of the nuclear...

  11. 10 CFR 10.4 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Policy. 10.4 Section 10.4 Energy NUCLEAR REGULATORY COMMISSION CRITERIA AND PROCEDURES FOR DETERMINING ELIGIBILITY FOR ACCESS TO RESTRICTED DATA OR NATIONAL... Nuclear Regulatory Commission to carry out its responsibility for the security of the nuclear...

  12. 43 CFR 10.4 - Inadvertent discoveries.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Inadvertent discoveries. 10.4 Section 10.4 Public Lands: Interior Office of the Secretary of the Interior NATIVE AMERICAN GRAVES PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony...

  13. 43 CFR 10.4 - Inadvertent discoveries.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Inadvertent discoveries. 10.4 Section 10.4 Public Lands: Interior Office of the Secretary of the Interior NATIVE AMERICAN GRAVES PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony...

  14. 43 CFR 10.4 - Inadvertent discoveries.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Inadvertent discoveries. 10.4 Section 10.4 Public Lands: Interior Office of the Secretary of the Interior NATIVE AMERICAN GRAVES PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony...

  15. 43 CFR 10.4 - Inadvertent discoveries.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Inadvertent discoveries. 10.4 Section 10.4 Public Lands: Interior Office of the Secretary of the Interior NATIVE AMERICAN GRAVES PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony...

  16. 43 CFR 10.4 - Inadvertent discoveries.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Inadvertent discoveries. 10.4 Section 10.4 Public Lands: Interior Office of the Secretary of the Interior NATIVE AMERICAN GRAVES PROTECTION AND REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony...

  17. 36 CFR 10.4 - Shipment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CERTAIN WILD ANIMALS § 10.4 Shipment. (a) Elk, buffaloes, and bears may be obtained at the Park and be removed by truck. Elk and buffaloes, when not transported by truck, must be crated individually for...

  18. 36 CFR 10.4 - Shipment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CERTAIN WILD ANIMALS § 10.4 Shipment. (a) Elk, buffaloes, and bears may be obtained at the Park and be removed by truck. Elk and buffaloes, when not transported by truck, must be crated individually for...

  19. 36 CFR 10.4 - Shipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CERTAIN WILD ANIMALS § 10.4 Shipment. (a) Elk, buffaloes, and bears may be obtained at the Park and be removed by truck. Elk and buffaloes, when not transported by truck, must be crated individually for...

  20. 36 CFR 10.4 - Shipment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CERTAIN WILD ANIMALS § 10.4 Shipment. (a) Elk, buffaloes, and bears may be obtained at the Park and be removed by truck. Elk and buffaloes, when not transported by truck, must be crated individually for...

  1. 36 CFR 10.4 - Shipment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CERTAIN WILD ANIMALS § 10.4 Shipment. (a) Elk, buffaloes, and bears may be obtained at the Park and be removed by truck. Elk and buffaloes, when not transported by truck, must be crated individually for...

  2. Flow injection spectrophotometric determination of sub-mg dm(-3) silver(I) in a strongly acidic solution containing concentrated copper(II) using a pyridylazo reagent.

    PubMed

    Fujimura, Kazuyoshi; Odake, Tamao; Takiguchi, Hiromi; Watanabe, Noriyuki; Sawada, Tsuguo

    2011-01-01

    A novel spectrophotometric flow injection method for determination of silver(I) in a strongly acidic solution containing concentrated copper(II) was developed using a coloring ligand, 4-(3,5-dibromo-2-pyridylazo)-N-ethyl-N-(3-sulfopropyl)aniline (3,5-diBr-PAESA). The method was first investigated by batch method. The interference from copper(II) chelate could be eliminated by the masking effect of EDTA. By utilizing the large formation constant (K = 12.3) of AgBr, one could determine silver(I) as a decrease of absorption by silver(I) chelate due to formation of AgBr by addition of KBr. Based on the results of batch experiments, two types of flow injection analysis (FIA) systems were constructed. Sub-mg dm(-3) determination of silver(I) was attained without interference from excess copper(II). The proposed method was successfully applied to determination of silver in a copper plating solution used in a plant to manufacture copper printed circuit boards, where the concentration of silver was critically important in the process control.

  3. 39 CFR 10.4 - Financial disclosure reports.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Financial disclosure reports. 10.4 Section 10.4... CONDUCT FOR POSTAL SERVICE GOVERNORS (ARTICLE X) § 10.4 Financial disclosure reports. (a) Requirement of submission of reports. At the time of their nomination, Governors complete a financial disclosure...

  4. 17 CFR 10.4 - Business address; hours.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Business address; hours. 10.4 Section 10.4 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION RULES OF PRACTICE General Provisions § 10.4 Business address; hours. The Office of Proceedings is located at Three...

  5. 17 CFR 10.4 - Business address; hours.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Business address; hours. 10.4 Section 10.4 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION RULES OF PRACTICE General Provisions § 10.4 Business address; hours. The Office of Proceedings is located at Three...

  6. 46 CFR 111.10-4 - Power requirements, generating sources.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Power requirements, generating sources. 111.10-4 Section 111.10-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING... services include cooking, heating, air conditioning (where installed), domestic refrigeration,...

  7. 46 CFR 111.10-4 - Power requirements, generating sources.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 111.10-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power requirements, generating sources. (a) The aggregate capacity of the electric ship's service generating sources required in § 111.10-3...

  8. 46 CFR 111.10-4 - Power requirements, generating sources.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 111.10-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power requirements, generating sources. (a) The aggregate capacity of the electric ship's service generating sources required in § 111.10-3...

  9. Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol

    NASA Astrophysics Data System (ADS)

    Konopelko, L. A.; Pankratov, V. V.; Pankov, A. A.; Ivahnenko, B. V.; Efremova, O. V.; Bakovec, N. V.; Mironchik, A. M.; Aleksandrov, V. V.

    2017-01-01

    This article presents the report on the COOMET supplementary comparison "Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol". Carbon monoxide (CO) is present in atmosphere due to different natural and anthropogenic sources. CO is a toxic gas and in concentrations higher than (3-5) μmol/mol it is hazardous to human health. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  10. International key comparison CCQM-K94: 10 μmol/mol dimethyl sulfide in nitrogen

    NASA Astrophysics Data System (ADS)

    Lee, S.; Heo, G. S.; Kim, Y.; Oh, S.; Han, Q.; Wu, H.; Konopelko, L. A.; Kustikov, Y. A.; Kolobova, A. V.; Efremova, O. V.; Pankratov, V. V.; Pavlov, M. V.; Culleton, L. P.; Brown, A. S.; Brookes, C.; Li, J.; Ziel, P. R.; van der Veen, A. M. H.

    2016-01-01

    Dimethyl sulfide (DMS) is an important compound in monitoring climate change and is monitored by the World Meteorological Organization Global Atmospheric Watch Volatile Organic Compounds (WMO-GAW VOC) program at several monitoring sites. It is essential that measurement results are accurate and consistent among the assigned values for primary gas mixtures to meet the WMO requirement. The purpose of this comparison is to compare the measurement capability of DMS at approximately 10 μ­mol/mol and expectation to contribute the establishment of traceability to single measurement scale for DMS between NMIs. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  11. Projecting a world of 10.4 billion.

    PubMed

    Yanagishita, M

    1988-01-01

    Summary data are presented from the World Bank's "World Population 1987-88: Short and Long-Term Estimates by Age and Sex with Related Demographic Statistics." The projections do not differ much from those in the World Bank's 1985 projection except for large upward revisions for South Asian and West Asian countries and especially large upward revisions for Kenya, Ethiopia, Burkina Faso, Nigeria, and Egypt. World population is expected to reach 10.4 billion in 2100 and to stabilize at 10 billion around year 2070. Intermediate figures are given for year 2000 (6.2 billion) and year 2050 (9.5 billion). The fifteen most populous countries in 2100 will be (in millions) China (1683), India (1678), Nigeria (529), Pakistan (395), USSR (385), Indonesia (363), Brazil (292), US (279), Ethiopia (204), Mexico (197), Iran (157), Philippines (137), Egypt (132), Japan (124), and Tanzania (123). The world's annual growth rate (currently 1.7%) will decrease to .9% in 2025 and .07% in 2100 due to decreasing birth rates, especially in Africa. Nevertheless, the population of Sub-Saharan Africa will be 5 times its present size. The slowest annual growth will be for Europe, North America, and China; and the highest for Sri Lanka, Pakistan, and Bangladesh.

  12. MolProbity for the masses—of data

    PubMed Central

    Chen, Vincent B.; Wedell, Jonathan R.; Wenger, R. Kent; Ulrich, Eldon L.

    2015-01-01

    MolProbity is a powerful software program for validating structures of proteins and nucleic acids. Although MolProbity includes scripts for batch analysis of structures, because these scripts analyze structures one at a time, they are not well suited for the validation of a large dataset of structures. We have created a version of MolProbity (MolProbity-HTC) that circumvents these limitations and takes advantage of a high-throughput computing cluster by using the HTCondor software. MolProbity-HTC enables the longitudinal analysis of large sets of structures, such as those deposited in the PDB or generated through theoretical computation—tasks that would have been extremely time-consuming using previous versions of MolProbity. We have used MolProbity-HTC to validate the entire PDB, and have developed a new visual chart for the BioMagResBank (BMRB) website that enables users to easily ascertain the quality of each model in an NMR ensemble and to compare the quality of those models to the rest of the PDB. PMID:26195077

  13. Optimized MOL-PCR for Characterization of Microbial Pathogens.

    PubMed

    Wuyts, Véronique; Roosens, Nancy H C; Bertrand, Sophie; Marchal, Kathleen; De Keersmaecker, Sigrid C J

    2016-01-06

    Characterization of microbial pathogens is necessary for surveillance, outbreak detection, and tracing of outbreak sources. This unit describes a multiplex oligonucleotide ligation-PCR (MOL-PCR) optimized for characterization of microbial pathogens. With MOL-PCR, different types of markers, like unique sequences, single-nucleotide polymorphisms (SNPs) and indels, can be simultaneously analyzed in one assay. This assay consists of a multiplex ligation for detection of the markers, a singleplex PCR for signal amplification, and hybridization to MagPlex-TAG beads for readout on a Luminex platform after fluorescent staining. The current protocol describes the MOL-PCR, as well as methods for DNA isolation, probe design, and data interpretation and it is based on an optimized MOL-PCR assay for subtyping of Salmonella Typhimurium.

  14. MOL1 is required for cambium homeostasis in Arabidopsis.

    PubMed

    Gursanscky, Nial Rau; Jouannet, Virginie; Grünwald, Karin; Sanchez, Pablo; Laaber-Schwarz, Martina; Greb, Thomas

    2016-05-01

    Plants maintain pools of pluripotent stem cells which allow them to constantly produce new tissues and organs. Stem cell homeostasis in shoot and root tips depends on negative regulation by ligand-receptor pairs of the CLE peptide and leucine-rich repeat receptor-like kinase (LRR-RLK) families. However, regulation of the cambium, the stem cell niche required for lateral growth of shoots and roots, is poorly characterized. Here we show that the LRR-RLK MOL1 is necessary for cambium homeostasis in Arabidopsis thaliana. By employing promoter reporter lines, we reveal that MOL1 is active in a domain that is distinct from the domain of the positively acting CLE41/PXY signaling module. In particular, we show that MOL1 acts in an opposing manner to the CLE41/PXY module and that changing the domain or level of MOL1 expression both result in disturbed cambium organization. Underlining discrete roles of MOL1 and PXY, both LRR-RLKs are not able to replace each other when their expression domains are interchanged. Furthermore, MOL1 but not PXY is able to rescue CLV1 deficiency in the shoot apical meristem. By identifying genes mis-expressed in mol1 mutants, we demonstrate that MOL1 represses genes associated with stress-related ethylene and jasmonic acid hormone signaling pathways which have known roles in coordinating lateral growth of the Arabidopsis stem. Our findings provide evidence that common regulatory mechanisms in different plant stem cell niches are adapted to specific niche anatomies and emphasize the importance of a complex spatial organization of intercellular signaling cascades for a strictly bidirectional tissue production.

  15. Comparison of primary standard gas mixtures: gravimetric production of carbon monoxide in nitrogen (3 μmol/mol)

    NASA Astrophysics Data System (ADS)

    Konopelko, L. A.; Kustikov, Y. A.; Kolobova, A. V.; Pankratov, V. V.; Pankov, A. A.; Efremova, O. V.; Augusto, Cristiane R.; Fioravante, Andreia L.; Ribeiro, Claudia C.; Teixeira, Denise C. G. S.; Elias, Elizandra C. S.; Oudwater, Rutger J.; Fagundes, Fátima A.; Silva, Marceli C.

    2016-01-01

    COOMET.QM-S3 is a supplementary comparison of primary standard gas mixtures—'Carbon monoxide in Nitrogen (3 μmol/mol)'. This is a bilateral comparison between VNIIM and INMETRO and it was conducted in 2013. Carbon monoxide is a toxic gas and in concentrations higher than 3-5 μmol/mol it is hazardous to human health. Therefore, it is important for NMIs to have the capability of an accurate carbon monoxide measurements. This comparison has shown that primary standard gas mixtures of carbon monoxide in nitrogen on the level of 3 μmol/mol, prepared in VNIIM and Inmetro, do not agree—the pair-wise degree of equivalence D (0.77%) is higher than the appropriate expanded uncertainty U(D) (0.29%). Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. eMOL Evaluating electron-water scattering data

    NASA Astrophysics Data System (ADS)

    Mason, Nigel

    2013-09-01

    The eMOL (electron molecule) project has been established to establish the process by which such data will be reviewed, validated and recommended data sets published. In particular eMOL seeks to suggest whether any particular data set be used as a primary or secondary source of data for the wider community. Primary would mean that is judged to the best representation of that particular interaction/cross section and therefore be used as a ``recommended'' value for users. The first target to be reviewed by eMOL was water with 8 members of the eMOL board meeting in Vienna in May 2013. The Board used the most recent review of electron-water scattering (Itikawa and Mason J. Phys. Chem. Ref. Data 34 1-22 (2005)) as its reference point. Over 80 papers (collected and disseminated by eMOL's bibliometrician Dr D Jaksch) that had been published subsequent to this review were reviewed and recommendations made as to whether such data should replace recommendations in the earlier review. The Meeting also identified areas (cross sections) for future research, data inconsistencies and reviewed the allocation of uncertainty estimates for complete datasets (assembled from a combination of both experimental and theoretical data). In this presentation I will therefore both present the findings of this review and discuss this study as an exemplar of the wider eMOL programme which will review some 15 electron-molecule datasets in 2013-15 including many of interest to the GEC (plasma) community.

  17. Results of postirradiation examination of the in-pile blockage experiments MOL-7C/4 and MOL-7C/5

    SciTech Connect

    Weimar, P.; Schleisiek, K. )

    1991-10-01

    The Mol-7C in-pile local blockage experiments are performed in the BR-2 reactor at Mol, Belgium as a joint project of Kernforchungszentrum Karlsruhe (KfK) and Studiecentrum voor Kernenergie/Centre d'Etude de l'Energie Nuclearire-Mol. The main objective is to investigate the consequences of local cooling disturbances in liquid-metal-cooled reactor (LMR) fuel subassemblies. In the tests Mol-7C/4 and MOL-7C/5, fuel pins from KNK II are used with a burnup of 5 and 1.7%, respectively. An active central porous blockage is used to simulate the cooling disturbance. During irradiation, the blockage causes significant local damage, including melting of cladding and fuel. Extensive postirradiation examinations (PIE) are performed to investigate the extent of damage. In this paper a description and interpretation of results of the destructive PIE performed at the Hot Cells Laboratory at KfK is given, along with some conclusions related to LMR safety.

  18. Influence of hydrofluoric acid on extraction of thorium using a commercially available extraction chromatographic resin.

    PubMed

    Shimada-Fujiwara, Asako; Hoshi, Akiko; Kameo, Yutaka; Nakashima, Mikio

    2009-05-01

    The dependence of Th recovery on hydrofluoric acid (HF) concentration in nitric acid (HNO(3)) solutions (1-5 mol/dm(3)) containing 1x10(-6) mol/dm(3) of Th and various concentrations of HF and the elution behavior were studied using a commercially available UTEVA (for uranium and tetravalent actinide) resin column. Thorium recovery decreased with an increase in HF concentration in the sample solutions. The concentration of HF at which Th recovery started to decrease was approximately 1x10(-4) mol/dm(3) in 1 mol/dm(3) HNO(3) solution, approximately 1x10(-3) mol/dm(3) in 3 mol/dm(3) HNO(3) solution, and approximately 1x10(-2) mol/dm(3) in 5 mol/dm(3) HNO(3) solution. When Al(NO(3))(3) (0.2 mol/dm(3)) or Fe(NO(3))(3) (0.6 mol/dm(3)) was added as a masking agent for F(-) to the Th solution containing 1x10(-1) mol/dm(3) HF and 1 mol/dm(3) HNO(3), Th recovery improved from 1.4+/-0.3% to 95+/-5% or 93+/-3%. Effective extraction of Th using UTEVA resin was achieved by selecting the concentration of HNO(3) and/or adding masking agents such as Al(NO(3))(3) according to the concentration of HF in the sample solution.

  19. 26 CFR 36.3121(l)(10)-4 - Payment of amounts equivalent to tax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 15 2013-04-01 2013-04-01 false Payment of amounts equivalent to tax. 36.3121(l)(10)-4 Section 36.3121(l)(10)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... SUBSIDIARIES § 36.3121(l)(10)-4 Payment of amounts equivalent to tax. A domestic corporation which has...

  20. 26 CFR 36.3121(l)(10)-4 - Payment of amounts equivalent to tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false Payment of amounts equivalent to tax. 36.3121(l)(10)-4 Section 36.3121(l)(10)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... SUBSIDIARIES § 36.3121(l)(10)-4 Payment of amounts equivalent to tax. A domestic corporation which has...

  1. 26 CFR 36.3121(l)(10)-4 - Payment of amounts equivalent to tax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 15 2012-04-01 2012-04-01 false Payment of amounts equivalent to tax. 36.3121(l)(10)-4 Section 36.3121(l)(10)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... SUBSIDIARIES § 36.3121(l)(10)-4 Payment of amounts equivalent to tax. A domestic corporation which has...

  2. 26 CFR 36.3121(l)(10)-4 - Payment of amounts equivalent to tax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 15 2011-04-01 2011-04-01 false Payment of amounts equivalent to tax. 36.3121(l)(10)-4 Section 36.3121(l)(10)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... SUBSIDIARIES § 36.3121(l)(10)-4 Payment of amounts equivalent to tax. A domestic corporation which has...

  3. 26 CFR 36.3121(l)(10)-4 - Payment of amounts equivalent to tax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 15 2014-04-01 2014-04-01 false Payment of amounts equivalent to tax. 36.3121(l)(10)-4 Section 36.3121(l)(10)-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... SUBSIDIARIES § 36.3121(l)(10)-4 Payment of amounts equivalent to tax. A domestic corporation which has...

  4. Crystal and mol-ecular structure of aflatrem.

    PubMed

    Lenta, Bruno N; Ngatchou, Jules; Kenfack, Patrice T; Neumann, Beate; Stammler, Hans-Georg; Sewald, Norbert

    2015-11-01

    The crystal structure of the title compound, C32H39NO4, confirms the absolute configuration of the seven chiral centres in the mol-ecule. The molecule has a 1,1-dimethylprop-2-enyl substituent on the indole nucleus and this nucleus shares one edge with the five-membered ring which is, in turn, connected to a sequence of three edge-shared fused rings. The skeleton is completed by the 7,7-trimethyl-6,8-dioxabi-cyclo-[3.2.1]oct-3-en-2-one group connected to the terminal cyclohexene ring. The two cyclohexane rings adopt chair and half-chair conformations, while in the dioxabi-cyclo-[3.2.1]oct-3-en-2-one unit, the six-membered ring has a half-chair conformation. The indole system of the mol-ecule exhibits a tilt of 2.02 (1)° between its two rings. In the crystal, O-H⋯O hydrogen bonds connect mol-ecules into chains along [010]. Weak N-H⋯π inter-actions connect these chains, forming sheets parallel to (10-1).

  5. Final report: international comparison APMP.QM-S7 methane in nitrogen at 2000 μmol/mol

    NASA Astrophysics Data System (ADS)

    Kim, Byungmoon; Bae, Hyounkil; Lee, Sangil; Oh, Sanghyub; Lin, Tsai-Yin; Huang, Chiug-Kun; Sinweeruthai, Ratirat; Rattanasombat, Soponrat; Laongsri, Bunthoon; Wongjuk, Arnuttachai; Li, Hou; Hui, Liu; Beng Keat, Teo; Mogale, David; Johri, Prabha; Tarhan, Tanil; Engin, Erinc

    2015-01-01

    Methane is one of the major greenhouse gases that affect climate change. To mitigate anthropogenic CH4 emissions effectively, it is necessary to measure and monitor CH4 emissions from fossil fuel combustion. Therefore, it is important for NMIs to have the capability of an accurate CH4 emissions measurement. The first key comparison on methane in nitrogen or air is the key comparison of CCQM-K82 (ambient level methane in air). As a supplementary comparison, the purpose of this comparison is to cover a concentration level that is not covered by previous key comparisons: this report describes the results of a supplementary comparison for methane in nitrogen at 2000 μmol/mol. Results from all participants, except two, agree well within their associated uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  6. [Use of mesquite cotyledon (Prosopis chilensis (Mol) Shuntz) in the manufacturing of cereal bars].

    PubMed

    Estévez, A M; Escobar, B; Ugarte, V

    2000-06-01

    Cereal bars with peanut and walnut has shown to be snack foods of good organoleptic characteristics and high caloric value, due to their content of protein, lipids and carbohydrates. Cotyledons of mezquite seeds have a high protein content which biological quality improves with thermal processing like toasting, microwave or moist heat under pressure. The purposes of this research were to study the use of mezquite cotyledon (Prosopis chilensis (Mol) Stuntz) in cereal bars with two different levels of peanut or walnut; and to determine the effect of two thermal treatment applied on the cotyledon upon the bar characteristics. Twelve different kind of bars were developed through the combination of two levels of peanut or walnut (15% and 18%); the use of mezquite cotyledon (0% and 6%); and the application of two thermal processing to the cotyledon (microwave and toasting). Cereal bars were analysed for chemical, physical and sensory characteristics: moisture, water activity, proximate chemical composition, sensory quality and acceptability. Moisture content of bars with peanut ranged between 10.4% and 10.9%; and for those with walnut, between 10.5% and 12.3%. Protein content was higher in the bars with mezquite cotiledon, being higher those with peanut. Thermal processing did not have any effect on the chemical composition. Bars with mezquite cotyledon treated by microwave showed a higher acceptability.

  7. Hypolipidemic and antihyperlipidemic effects of Lagenaria siceraria (Mol.) fruit extracts.

    PubMed

    Ghule, B V; Ghante, M H; Saoji, A N; Yeole, P G

    2006-11-01

    Bottle gourd [(Lagenaria siceraria (Mol.) Stand.] fruit is ascribed with many therapeutic effects. The present study was undertaken to explore the antihyperlipidemic effect of four different extracts viz. petroleum ether, chloroform, alcoholic and aqueous extracts from bottle gourd in Triton-induced hyperlipidemic rats and their hypolipidemic effects in normocholesteremic rats. The study is comprised preliminary phytochemical screening of the extracts. Oral administration of the extracts, at doses of 200 and 400 mg/kg body weight in rats, dose-dependently inhibited the total cholesterol, triglycerides, low-density lipoproteins level, and significantly increased the high density lipoproteins level. However, petroleum ether extract did not show the significant effects. Both the chloroform and alcoholic extract exhibited more significant effects in lowering total cholesterol, triglycerides and low density lipoproteins along with increase in HDL as compared to the others. Preliminary phytochemical screening revealed the presence of flavonoids, sterols, cucurbitacin saponins, polyphenolics, proteins, and carbohydrates. The results obtained suggest marked antihyperlipidemic and hypolipidemic activity of the extracts.

  8. Dynamique moléculaire et canaux ioniques

    NASA Astrophysics Data System (ADS)

    Crouzy, S.

    2005-11-01

    Diffusion de neutrons et Dynamique Moléculaire (DM) sont deux techniques intimement liées car elles portent sur les mêmes échelles de temps: la première apporte des informations structurales ou dynamiques sur le système physique ou biologique, la seconde permet de décoder ces informations à travers un modèle facilitant l'interprétation des résultats. Au delà de l'intérêt que la technique de DM peut avoir en relation directe avec les neutrons, il est intéressant de comprendre comment les modèles sont construits et comment les techniques de simulation peuvent aller beaucoup plus loin que de simples modélisations. Nous décrirons brièvement, dans la suite de cet exposé, la technique de DM et les méthodes plus sophistiquées de calculs d'énergie libre et de potentiels de force moyenne à partir des simulations de DM. Puis nous verrons avec deux exemples tirés de nos travaux théoriques sur les canaux ioniques comment ces calculs peuvent nous donner accès à des vitesses de réaction ou des constantes d'affinité ou de liaison. La première étude porte sur un analogue de la gramicidine A qui forme un canal conducteur d'ions interrompus par le basculement d'un cycle dioxolane [1]. La seconde concerne le canal potassique KcsA dont nous avons étudié le blocage du coté extracellulaire par l'ion Tetra Ethyl Ammonium [2].

  9. 15 CFR 10.4 - Establishment of the Standard Review Committee.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... THE DEVELOPMENT OF VOLUNTARY PRODUCT STANDARDS § 10.4 Establishment of the Standard Review Committee... other appropriate general interest groups such as State and Federal agencies. When requested by the... final development of the standard, or for 2 years, whichever is less. (c) The Department shall...

  10. Deep Sub-micro mol{\\cdot }mol^{-1} Water-Vapor Measurement by Dual-Ball SAW Sensors for Temperature Compensation

    NASA Astrophysics Data System (ADS)

    Takeda, N.; Oizumi, T.; Tsuji, T.; Akao, S.; Takayanagi, K.; Nakaso, N.; Yamanaka, K.

    2015-12-01

    A collimated surface acoustic wave (SAW) circles around the equator of a sphere hundreds of times. Because of the long distance travel of the collimated SAW, a small change in the SAW propagation caused by the environment of the sphere can be accumulated as a measurable range in amplitude and/or in delay time. So, a spherical SAW device enables highly sensitive water-vapor measurements. In this paper, deep sub \\upmu mol{\\cdot }mol^{-1} water-vapor detection by 1 mm diameter quartz crystal ball SAW sensors is described. To measure such a low water-vapor concentration in real time, it is necessary to compensate the temperature dependence of the ball SAW sensor, which is about 20 ppm{\\cdot }°C^{-1} in delay time change. A dual-frequency burst analog detector was developed for the temperature compensation in real time. By using a harmonic SAW sensor, which was excited by 80 MHz and 240 MHz at the same time, it was confirmed that the delay time drift for a temperature range of 21.0°C ± 1.0°C became less than 0.05 ppm in delay time change. By using dual-ball SAW sensors (which included a 150 MHz sensor with a water-vapor sensitive layer and a 240 MHz sensor as a reference), water-vapor concentrations from 0.1 \\upmu mol{\\cdot }mol^{-1} to 5 \\upmu mol{\\cdot }mol^{-1} were successfully measured. It appears that the delay time change is proportional to the square root of the water-vapor concentration. The detection limit determined by the electrical noise of the system was estimated at 0.01 \\upmu mol{\\cdot }mol^{-1}.

  11. 41 CFR 302-10.4 - Are there any geographic limitations for transportation of a mobile home?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... limitations for transportation of a mobile home? 302-10.4 Section 302-10.4 Public Contracts and Property...-ALLOWANCES FOR TRANSPORTATION OF MOBILE HOMES AND BOATS USED AS A PRIMARY RESIDENCE Eligibility and Limitations § 302-10.4 Are there any geographic limitations for transportation of a mobile home?...

  12. 41 CFR 302-10.4 - Are there any geographic limitations for transportation of a mobile home?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... limitations for transportation of a mobile home? 302-10.4 Section 302-10.4 Public Contracts and Property...-ALLOWANCES FOR TRANSPORTATION OF MOBILE HOMES AND BOATS USED AS A PRIMARY RESIDENCE Eligibility and Limitations § 302-10.4 Are there any geographic limitations for transportation of a mobile home?...

  13. 41 CFR 302-10.4 - Are there any geographic limitations for transportation of a mobile home?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... limitations for transportation of a mobile home? 302-10.4 Section 302-10.4 Public Contracts and Property...-ALLOWANCES FOR TRANSPORTATION OF MOBILE HOMES AND BOATS USED AS A PRIMARY RESIDENCE Eligibility and Limitations § 302-10.4 Are there any geographic limitations for transportation of a mobile home?...

  14. 41 CFR 302-10.4 - Are there any geographic limitations for transportation of a mobile home?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... limitations for transportation of a mobile home? 302-10.4 Section 302-10.4 Public Contracts and Property...-ALLOWANCES FOR TRANSPORTATION OF MOBILE HOMES AND BOATS USED AS A PRIMARY RESIDENCE Eligibility and Limitations § 302-10.4 Are there any geographic limitations for transportation of a mobile home?...

  15. 41 CFR 302-10.4 - Are there any geographic limitations for transportation of a mobile home?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... limitations for transportation of a mobile home? 302-10.4 Section 302-10.4 Public Contracts and Property...-ALLOWANCES FOR TRANSPORTATION OF MOBILE HOMES AND BOATS USED AS A PRIMARY RESIDENCE Eligibility and Limitations § 302-10.4 Are there any geographic limitations for transportation of a mobile home?...

  16. Optical properties of LiNbO3:Mg(5.21 mol %) and LiNbO3:Fe(0.009 mol %):Mg(5.04 mol %) crystals

    NASA Astrophysics Data System (ADS)

    Sidorov, N. V.; Palatnikov, M. N.; Kruk, A. A.; Yanichev, A. A.; Makarova, O. V.; Teplyakova, N. A.; Pikoul, O. Yu.

    2014-02-01

    Using methods of electronic spectroscopy, laser conoscopy, photoinduced (photoreactive) light scattering, and Raman light-scattering spectroscopy, we have studied the optical homogeneity, optical transmission, and photorefractive properties of single crystals LiNbO3:Mg(5.21 mol %) and LiNbO3:Fe(0.009 mol %):Mg(5.04 mol %) that were grown from congruent melts. We have ascertained that doping with "nonphotorefractive" Mg2+ cations causes suppression of the photorefractive effect in a lithium-niobate crystal. Upon double doping (Fe:Mg), if the concentration of Mg2+ cations exceeds the threshold concentration, the photorefractive effect is almost not observed and the presence of "photorefractive" Fe cations does not affect the photorefractive effect as strongly as in congruent crystals doped with Fe.

  17. 10. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO SOUTHWEST, ...

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

    10. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO SOUTHWEST, WITH AUTOMATIC CUTTER (LEFT), PRESS (CENTER), AND WRAPPER (RIGHT); LARGE CHUTE AT CENTER FROM 5TH FLOOR BINS TO 3RD FLOOR SOAP MILLS; OVERHEAD AND FLOOR (LOWER RIGHT) FINISHED GOODS CONVEYORS TO G BLOCK (HAER NO. NJ-71-NN) - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

  18. GridMol: a grid application for molecular modeling and visualization

    NASA Astrophysics Data System (ADS)

    Sun, Yanhua; Shen, Bin; Lu, Zhonghua; Jin, Zhong; Chi, Xuebin

    2008-02-01

    In this paper we present GridMol, an extensible tool for building a high performance computational chemistry platform in the grid environment. GridMol provides computational chemists one-stop service for molecular modeling, scientific computing and molecular information visualization. GridMol is not only a visualization and modeling tool but also simplifies control of remote Grid software that can access high performance computing resources. GridMol has been successfully integrated into China National Grid, the most powerful Chinese Grid Computing platform. In Section "Grid computing" of this paper, a computing example is given to show the availability and efficiency of GridMol. GridMol is coded using Java and Java3D for portability and cross-platform compatibility (Windows, Linux, MacOS X and UNIX). GridMol can run not only as a stand-alone application, but also as an applet through web browsers. In this paper, we will present the techniques for molecular visualization, molecular modeling and grid computing. GridMol is available free of charge under the GNU Public License (GPL) from our website: http://www.sccas.cn/ syh/GridMol/index.html.

  19. Financial services FY 1995 site support program plan WBS 6.10.4

    SciTech Connect

    Vodney, E.P.

    1994-09-01

    This is the signed Financial Service fiscal year 1995 Site Support Program Plan, Work Breakdown Structure 6.10.4, for the Hanford site. This plan is intended to enable the contractor to accomplish the following: ensure financial integrity in all Westinghouse Hanford Company (WHC) operation while supporting the programmatic activities of WHC, the US Department of Energy, Richland Operations Office, and other Hanford contractors; provide efficient and effective financial services, and value added audits and review that enable management to enhance future operational results.

  20. HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales

    DOE PAGES

    Riccardi, Demian M.; Parks, Jerry M.; Johs, Alexander; ...

    2015-03-20

    HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. We tested the core; it is well-documented and easy to install across computational platforms. Our goal for the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, anmore » abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.« less

  1. HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales

    SciTech Connect

    Riccardi, Demian M.; Parks, Jerry M.; Johs, Alexander; Smith, Jeremy C.

    2015-03-20

    HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. We tested the core; it is well-documented and easy to install across computational platforms. Our goal for the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, an abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.

  2. An Introduction to Using the Method of Levels (MOL) Therapy to Work with People Experiencing Psychosis.

    PubMed

    Tai, Sara J

    2016-01-01

    This paper provides a basic introduction to using method of levels (MOL) therapy with people experiencing psychosis. As MOL is a direct application of perceptual control theory (PCT), a brief overview of the three main theoretical principles of this theory--control, conflict, and reorganization will be outlined in relation to understanding psychosis. In particular, how these principles form the basis of problem conceptualisation and determine what an MOL therapist is required to do during therapy will be illustrated. A practical description of MOL will be given, using case examples and short excerpts of therapeutic interactions. Some direct contrasts will also be made with cognitive behaviour therapy for psychosis (CBTp) and psychodynamic approaches (PA) in order to help illustrate the theory and practice of MOL.

  3. HackaMol: An Object-Oriented Modern Perl Library for Molecular Hacking on Multiple Scales.

    PubMed

    Riccardi, Demian; Parks, Jerry M; Johs, Alexander; Smith, Jeremy C

    2015-04-27

    HackaMol is an open source, object-oriented toolkit written in Modern Perl that organizes atoms within molecules and provides chemically intuitive attributes and methods. The library consists of two components: HackaMol, the core that contains classes for storing and manipulating molecular information, and HackaMol::X, the extensions that use the core. The core is well-tested, well-documented, and easy to install across computational platforms. The goal of the extensions is to provide a more flexible space for researchers to develop and share new methods. In this application note, we provide a description of the core classes and two extensions: HackaMol::X::Calculator, an abstract calculator that uses code references to generalize interfaces with external programs, and HackaMol::X::Vina, a structured class that provides an interface with the AutoDock Vina docking program.

  4. MolAxis: Efficient and Accurate Identification of Channels in Macromolecules

    PubMed Central

    Yaffe, Eitan; Fishelovitch, Dan; Wolfson, Haim J.; Halperin, Dan; Nussinov, Ruth

    2009-01-01

    Channels and cavities play important roles in macromolecular functions, serving as access/exit routes for substrates/products, cofactor and drug binding, catalytic sites, and ligand/protein. In addition, channels formed by transmembrane proteins serve as transporters and ion channels. MolAxis is a new sensitive and fast tool for the identification and classification of channels and cavities of various sizes and shapes in macromolecules. MolAxis constructs corridors, which are pathways that represent probable routes taken by small molecules passing through channels. The outer medial axis of the molecule is the collection of points that have more than one closest atom. It is composed of two-dimensional surface patches and can be seen as a skeleton of the complement of the molecule. We have implemented in MolAxis a novel algorithm that uses state-of-the-art computational geometry techniques to approximate and scan a useful subset of the outer medial axis, thereby reducing the dimension of the problem and consequently rendering the algorithm extremely efficient. MolAxis is designed to identify channels that connect buried cavities to the outside of macromolecules and to identify transmembrane channels in proteins. We apply MolAxis to enzyme cavities and transmembrane proteins. We further utilize MolAxis to monitor channel dimensions along Molecular Dynamics trajectories of a human Cytochrome P450. MolAxis constructs high quality corridors for snapshots at picosecond time-scale intervals substantiating the gating mechanism in the 2e substrate access channel. We compare our results with previous tools in terms of accuracy, performance and underlying theoretical guarantees of finding the desired pathways. MolAxis is available on line as a web-server and as a standalone easy-to-use program (http://bioinfo3d.cs.tau.ac.il/MolAxis/). PMID:18393395

  5. Fotoexcitación de Moléculas Pequeñas

    NASA Astrophysics Data System (ADS)

    González Díaz, P. F.

    El modelo estocástico no puede justificar la excitación multi-fotónica de moléculas pequeñas o muy simétricas. Basándonos en un escenario de interacción radiación-molécula cooperativo para la absorción de N-1 fotones IR por un sistema de N niveles, se especula que un posible mecanismo para la excitación no estocástica de moléculas pudiera ser la generación de procesos caóticos intra-moleculares.

  6. Hydrocarbon gas standards at the pmol/mol level to support ambient atmospheric measurements.

    PubMed

    Rhoderick, George C; Duewer, David L; Ning, Li; DeSirant, Kathryn

    2010-02-01

    Studies of climate change increasingly recognize the diverse influences exerted by hydrocarbons in the atmosphere, including roles in particulates and ozone formation. Measurements of key non-methane hydrocarbons (NMHCs) suggest atmospheric concentrations ranging from low pmol/mol to nmol/mol, depending on location and compound. To accurately establish concentration trends and to relate measurement records from many laboratories and researchers, it is essential to have good calibration standards. Several of the world's National Metrology Institutes (NMIs) are developing primary and secondary reference gas standards at the nmol/mol level. While the U.S. NMI, the National Institute of Standards and Technology (NIST), has developed pmol/mol standards for halocarbons and some volatile organics, the feasibility of preparing well-characterized, stable standards for NMHCs at the pmol/mol level is not yet established. NIST recently developed a suite of primary standards by gravimetric dilution that contains 18 NMHCs covering the concentration range of 60 pmol/mol to 230 pmol/mol. Taking into account the small but chemically significant contribution of NMHCs in the high-purity diluent nitrogen used in their preparation, the relative concentrations and short-term stability (2 to 3 months) of these NMHCs in the primary standards have been confirmed by chromatographic analysis. The gravimetric values assigned from the methods used to prepare the materials and the analytical concentrations determined from chromatographic analysis generally agree to within +/-2 pmol/mol. However, anomalous results for several of the compounds reflect the difficulties inherent in avoiding contamination and making accurate measurements at these very low levels.

  7. Revision of the gas-phase acidity scale below 300 kcal mol(-1).

    PubMed

    Leito, Ivo; Raamat, Elin; Kütt, Agnes; Saame, Jaan; Kipper, Karin; Koppel, Ilmar A; Koppel, Ivar; Zhang, Min; Mishima, Masaaki; Yagupolskii, Lev M; Garlyauskayte, Romute Yu; Filatov, Andrey A

    2009-07-23

    The gas-phase acidity (GA) scale from (CF(3)CO)(2)NH to (C(2)F(5)SO(2))(2)NH--about a 24 kcal mol(-1) range of gas-phase acidities--was reexamined using the Fourier transform ion cyclotron resonance equilibrium measurement approach. Some additions and modifications to the standard methodology of GA measurements were introduced (estimation of partial pressures from mass spectra of the compounds, instead of the pressure gauge readings and use of long reaction times) to achieve higher reliability. Gas-phase acidities of 18 compounds were determined for the first time. The results reveal a contraction of the previously published values in this part of the scale. In particular, the GA values of (CF(3)SO(2))(2)NH and (C(2)F(5)SO(2))(2)NH (important components of lithium ion battery electrolytes and ionic liquids) were revised toward stronger acidities from 291.8 kcal mol(-1) to 286.5 kcal mol(-1) and from 289.4 kcal mol(-1) to 283.7 kcal mol(-1) (i.e., by 5.3 and 5.7 kcal mol(-1)), respectively. Experimental and computational evidence is presented in support of the current results.

  8. Adsorption and migration of single metal atoms on the calcite (10.4) surface.

    PubMed

    Pinto, H; Haapasilta, V; Lokhandwala, M; Öberg, S; Foster, Adam S

    2017-04-05

    Transition metal atoms are one of the key ingredients in the formation of functional 2D metal organic coordination networks. Additionally, the co-deposition of metal atoms can play an important role in anchoring the molecular structures to the surface at room temperature. To gain control of such processes requires the understanding of adsorption and diffusion properties of the different transition metals on the target surface. Here, we used density functional theory to investigate the adsorption of 3d (Ti, Cr, Fe, Ni, Cu), 4d (Zr, Nb, Mo, Pd, Ag) and 5d (Hf, W, Ir, Pt, Au) transition metal adatoms on the insulating calcite (10.4) surface. We identified the most stable adsorption sites and calculated binding energies and corresponding ground state structures. We find that the preferential adsorption sites are the Ca-Ca bridge sites. Apart from the Cr, Mo, Cu, Ag and Au all the studied metals bind strongly to the calcite surface. The calculated migration barriers for the representative Ag and Fe atoms indicates that the metal adatoms are mobile on the calcite surface at room temperature. Bader analysis suggests that there is no significant charge transfer between the metal adatoms and the calcite surface.

  9. Adsorption and migration of single metal atoms on the calcite (10.4) surface

    NASA Astrophysics Data System (ADS)

    Pinto, H.; Haapasilta, V.; Lokhandwala, M.; Öberg, S.; Foster, Adam S.

    2017-04-01

    Transition metal atoms are one of the key ingredients in the formation of functional 2D metal organic coordination networks. Additionally, the co-deposition of metal atoms can play an important role in anchoring the molecular structures to the surface at room temperature. To gain control of such processes requires the understanding of adsorption and diffusion properties of the different transition metals on the target surface. Here, we used density functional theory to investigate the adsorption of 3d (Ti, Cr, Fe, Ni, Cu), 4d (Zr, Nb, Mo, Pd, Ag) and 5d (Hf, W, Ir, Pt, Au) transition metal adatoms on the insulating calcite (10.4) surface. We identified the most stable adsorption sites and calculated binding energies and corresponding ground state structures. We find that the preferential adsorption sites are the Ca–Ca bridge sites. Apart from the Cr, Mo, Cu, Ag and Au all the studied metals bind strongly to the calcite surface. The calculated migration barriers for the representative Ag and Fe atoms indicates that the metal adatoms are mobile on the calcite surface at room temperature. Bader analysis suggests that there is no significant charge transfer between the metal adatoms and the calcite surface.

  10. International comparison of a hydrocarbon gas standard at the picomol per mol level.

    PubMed

    Rhoderick, George C; Duewer, David L; Apel, Eric; Baldan, Annarita; Hall, Bradley; Harling, Alice; Helmig, Detlev; Heo, Gwi Suk; Hueber, Jacques; Kim, Mi Eon; Kim, Yong Doo; Miller, Ben; Montzka, Steve; Riemer, Daniel

    2014-03-04

    Studies of climate change increasingly recognize the diverse influences of hydrocarbons in the atmosphere, including roles in particulates and ozone formation. Measurements of key nonmethane hydrocarbons (NMHCs) suggest atmospheric mole fractions ranging from low picomoles per mol (ppt) to nanomoles per mol (ppb), depending on location and compound. To accurately establish mole fraction trends and to relate measurement records from many laboratories and researchers, it is essential to have accurate, stable, calibration standards. In February of 2008, the National Institute of Standards and Technology (NIST) developed and reported on picomoles per mol standards containing 18 nonmethane hydrocarbon compounds covering the mole fraction range of 60 picomoles per mol to 230 picomoles per mol. The stability of these gas mixtures was only characterized over a short time period (2 to 3 months). NIST recently prepared a suite of primary standard gas mixtures by gravimetric dilution to ascertain the stability of the 2008 picomoles per mol NMHC standards suite. The data from this recent chromatographic intercomparison of the 2008 to the 2011 suites confirm a much longer stability of almost 5 years for 15 of the 18 hydrocarbons; the double-bonded alkenes of propene, isobutene, and 1-pentene showed instability, in line with previous publications. The agreement between the gravimetric values from preparation and the analytical mole fractions determined from regression illustrate the internal consistency of the suite within ±2 pmol/mol. However, results for several of the compounds reflect stability problems for the three double-bonded hydrocarbons. An international intercomparison on one of the 2008 standards has also been completed. Participants included National Metrology Institutes, United States government laboratories, and academic laboratories. In general, results for this intercomparison agree to within about ±5% with the gravimetric mole fractions of the hydrocarbons.

  11. Synthesis, Structure, and Characterization of Cu4S10(4-methylpyridine)4

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Richman, Robert M.; Duraj, Stan A.; Andras, Maria T.; Moore, Hall L.; Sabat, Michal; Eckles, William E.; Martuch, Robert A.

    1996-01-01

    The title compound, Cu4S10(4-methylpyridine)(sub 4) (dot) 4-methylpyridine was prepared by three different reactions: the oxidation of copper powder by sulfur and the reaction of copper (I) sulfide (or CuBr (dot) SMe2) with excess sulfur, both in the coordinating solvent, 4-methylpyridine. Red crystals of the compound obtained by layering with hexanes were subjected to single crystal X-ray diffraction. The structure was refined to R = 0.026 and R(sub w) = 0.036 in a space group P1bar (No. 2), with Z = 2, a = 13.983 (2) A, b = 15.384 (2) A, c = 9.660 (1) A, alpha = 93.87 (1)deg., beta = 93.38 (1)deg., gamma = 99.78 (1)deg., V = 2037.9 (9) A(exp 3). The compound has approximate S(sub 4) symmetry and consists of two pentasulfide chains linking four Cu(I) ions, each with a corrdinating 2-methylpyridine. The infrared spectrum was dominated by absorption due to coordinated 4-methylpyridine with several low-energy peaks attributable to S-S stretches, which were also observed by Raman spectroscopy. A featureless electronic absorption spectrum yielded a single peak in the near ultraviolet upon computer enhancement (lambda = 334 nm, epsilon = 10,000), most likely an intraligand transition. Cyclic voltammetry indicates that the polysulfide complex undergoes irrversible oxidation and reduction at +0.04 and -0.34 V vs. SCE, respectively, at 298 K in 4-methylpyridine when swept at 20 mV/sec. The electrochemical behavior was unvaried even at sweep rates as high as 100 V/sec.

  12. Experimental and theoretical study of anion-exchange preparative chromatography for neptunium: the first application to thorium(IV) and its equilibrium and kinetics.

    PubMed

    Yamamura, Tomoo; Miyakoshi, Takeshi; Shiokawa, Yoshinobu; Mitsugashira, Toshiaki

    2007-10-26

    In order to study equilibrium and kinetic parameters in anion-exchange chromatography for preparatory purpose, a quantitative model for nonlinear anion-exchange chromatography in porous media was constructed, by paying special attention to interstitial length along void structure (cm) distinguished from apparent length (cm*). Langmuir-type adsorption isotherm for thorium(IV), as a natural substitution for neptunium(IV), in 6 mol dm(-3) nitric acid to anion-exchanger MSA-1 (200-400 mesh) was investigated in batch-wise and chromatographic experiments. The equilibrium parameters determined by batch-wise experiments determined as k=2.4x10(2) mol(-1) dm3 s(-1) and s0=0.5 mol dm(-3) agrees very well with the values of k=222 mol(-1) dm3 s(-1) and s0=0.5 mol dm(-3) derived from fitting by the numerical calculation. Kinetic parameters of ks and D affect band profile similarly, thereby maximum value of each parameter was evaluated as ks=1.3 mol(-1) dm3 s(-1) and D=9x10(-4) cm2 s(-1) by the numerical calculations.

  13. Polygenic expression of teratozoospermia and normal fertility in B10.MOL-TEN1 mouse strain.

    PubMed

    Hirawatari, Keitaro; Hanzawa, Naoto; Kuwahara, Maki; Aoyama, Hiroaki; Miura, Ikuo; Wakana, Shigeharu; Gotoh, Hideo

    2015-05-01

    Subfertility and infertility are two major reproductive health problems in human and domestic animals. The contribution of the genotype to these conditions is poorly understood. To examine the genetic basis of male subfertility, we analyzed its relationship to sperm morphology in B10.MOL-TEN1 mice, which shows high-frequencies (about 50%) of morphologically abnormal sperm. Drastic histological changes were also found in the testis of the B10.MOL-TEN1. Segregation analysis showed that the abnormal sperm phenotype in B10.MOL-TEN1 was inherited and was predictably controlled by at least three loci. We also found that male fertility of this strain was normal. These findings indicate a complicated relationship between sperm morphology and male subfertility.

  14. Reevaluation of Neptunium-Nitric Acid Radiation Chemistry by Multiscale Modeling.

    PubMed

    Horne, G P; Grimes, T S; Mincher, B J; Mezyk, S P

    2016-12-15

    Multiscale modeling has been used to quantitatively reevaluate the radiation chemistry of neptunium in a range of aerated nitric acid solutions (0.1-6.0 mol dm(-3)). Exact calculation of initial radiolytic yields accounting for changes in radiation track chemistry was found to be crucial for reproducing experimental data. The γ irradiation induces changes in the Np(VI)/Np(V) oxidation-state distribution, predominantly driven by reactions involving HNO2, H2O2, NO2(•), and NO3(•) from the radiolysis of aqueous nitric acid. Oxidation of Np(V) by NO3(•) (k = 8.1 × 10(8) dm(3) mol(-1) s(-1)) provides the initial increase in Np(VI) concentration, while also delaying net reduction of Np(VI) by consuming HNO2. Reduction of Np(VI) is dominated by thermal reactions with HNO2 (k = 0.7-73 dm(3) mol(-1) s(-1)) and H2O2 (k = 1.9 dm(3) mol(-1) s(-1)). A steady state is eventually established once the concentration of Np(V) is sufficiently high to be oxidized by NO2(•) (k = 2.4 × 10(2)-3.1 × 10(4dm(3mol(-1) s(-1)). An additional thermal oxidation reaction between Np(V) and HNO3 (k = 2.0 × 10(3) dm(3) mol(-1) s(-1)) is required for nitric acid concentrations >4.0 mol dm(-3). For 0.1 mol dm(-3) HNO3, the rate of Np(VI) reduction is in excess of that which can be accounted for by radiolytic product mass balance, suggesting the existence of a catalytic-acid-dependent reduction process.

  15. CO/H2 Abundance Ratio ≈ 10-4 in a Protoplanetary Disk

    NASA Astrophysics Data System (ADS)

    France, Kevin; Herczeg, Gregory J.; McJunkin, Matthew; Penton, Steven V.

    2014-10-01

    The relative abundances of atomic and molecular species in planet-forming disks around young stars provide important constraints on photochemical disk models and provide a baseline for calculating disk masses from measurements of trace species. A knowledge of absolute abundances, those relative to molecular hydrogen (H2), are challenging because of the weak rovibrational transition ladder of H2 and the inability to spatially resolve different emission components within the circumstellar environment. To address both of these issues, we present new contemporaneous measurements of CO and H2 absorption through the "warm molecular layer" of the protoplanetary disk around the Classical T Tauri Star RW Aurigae A. We use a newly commissioned observing mode of the Hubble Space Telescope Cosmic Origins Spectrograph to detect warm H2 absorption in this region for the first time. An analysis of the emission and absorption spectrum of RW Aur shows components from the accretion region near the stellar photosphere, the molecular disk, and several outflow components. The warm H2 and CO absorption lines are consistent with a disk origin. We model the 1092-1117 Å spectrum of RW Aur to derive log10 N(H2) = 19.90+0.33-0.22 cm-2 at T rot(H2) = 440 ± 39 K. The CO A - X bands observed from 1410 to 1520 Å are best fit by log10 N(CO) = 16.1 +0.3-0.5 cm-2 at T rot(CO) = 200+650-125 K. Combining direct measurements of the H I, H2, and CO column densities, we find a molecular fraction in the warm disk surface of f H2 >= 0.47 and derive a molecular abundance ratio of CO/H2 = 1.6+4.7-1.3 × 10-4, both consistent with canonical interstellar dense cloud values. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555.

  16. COOMET.QM-K93 (COOMET 615/RU/13): key comparison in the field of measuring of the ethanol amount fraction in nitrogen (120 μmol/mol)

    NASA Astrophysics Data System (ADS)

    Konopelko, L. A.; Efremova, O. V.; Fatina, O. V.; Orshanskaia, A. A.; Rozhnov, M. S.; Melnyk, D. M.; Petryshyn, P. V.

    2016-01-01

    The relevance of the COOMET.QM-K93 comparison is founded on paying particular attention to reliability of measurements which are performed during the medical examination of drivers of vehicles in order to assess the degree of alcoholic intoxication. Standard gas mixtures of ethanol in nitrogen in cylinders under pressure play a key role in providing metrological assurance of breath-alcohol analyzers. Participating laboratories: VNIIM and Ukrmetrteststandart. This comparison was carried out in 2014-2015. This supplementary comparison supports CMC claims for: ethanol in the range 50-500 μmol/mol in a matrix of either nitrogen or synthetic air. Results: The results are consistent with the reference values. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  17. Mol-ecular and crystal structure of gossypol tetra-methyl ether with an unknown solvate.

    PubMed

    Honkeldieva, Muhabbat; Talipov, Samat; Mardanov, Rustam; Ibragimov, Bakhtiyar

    2015-02-01

    The title compound, C34H38O8 (systematic name: 5,5'-diisopropyl-2,2',3,3'-tetra-meth-oxy-7,7'-dimethyl-2H,2'H-8,8'-bi-[naphtho-[1,8-bc]furan]-4,4'-diol), has been obtained from a gossypol solution in a mixture of dimethyl sulfate and methanol. The mol-ecule is situated on a twofold rotation axis, so the asymmetric unit contains one half-mol-ecule. In the mol-ecule, the hy-droxy groups are involved in intra-molecular O-H⋯O hydrogen bonds, and the two naphthyl fragments are inclined each to other by 83.8 (1)°. In the crystal, weak C-H⋯O and C-H⋯π inter-actions consolidate the packing, which exhibits channels with an approximate diameter of 6 Å extending along the c-axis direction. These channels are filled with highly disordered solvent mol-ecules, so their estimated scattering contribution was subtracted from the observed diffraction data using the SQUEEZE option in PLATON [Spek, A. L. (2015). Acta Cryst. C71, 9-18].

  18. Élaboration de films de molécules organiques par ablation par laser UV

    NASA Astrophysics Data System (ADS)

    Hernandez-Perez, M. A.; Garapon, C.; Champeaux, C.; Coleman, A. W.

    2006-12-01

    Les potentialités des méthodes de dépôt par ablation laser (PLD) pour la préparation de films minces de matériaux organiques sont illustrées par un bref rappel bibliographique et par des résultats expérimentaux concernant des molécules d'intérêt biologique (acides aminés, calix-arènes, protéines). Les films sont préparés par PLD avec un laser KrF sans dégradation de la structure chimique des molécules dans une gamme de fluences de quelques dizaines à quelques centaines de mJ/cm2. Les propriétés structurales et optiques des films sont étudiées en fonction de la fluence du laser et mettent en évidence des arrangements moléculaires particuliers induits par cette méthode de dépôt. Le guidage optique a été obtenu pour des films de toutes ces molécules.

  19. Simplifying and enhancing the use of PyMOL with horizontal scripts.

    PubMed

    Mooers, Blaine H M

    2016-10-01

    Scripts are used in PyMOL to exert precise control over the appearance of the output and to ease remaking similar images at a later time. We developed horizontal scripts to ease script development. A horizontal script makes a complete scene in PyMOL like a traditional vertical script. The commands in a horizontal script are separated by semicolons. These scripts are edited interactively on the command line with no need for an external text editor. This simpler workflow accelerates script development. In using PyMOL, the illustration of a molecular scene requires an 18-element matrix of view port settings. The default format spans several lines and is laborious to manually reformat for one line. This default format prevents the fast assembly of horizontal scripts that can reproduce a molecular scene. We solved this problem by writing a function that displays the settings on one line in a compact format suitable for horizontal scripts. We also demonstrate the mapping of aliases to horizontal scripts. Many aliases can be defined in a single script file, which can be useful for applying costume molecular representations to any structure. We also redefined horizontal scripts as Python functions to enable the use of the help function to print documentation about an alias to the command history window. We discuss how these methods of using horizontal scripts both simplify and enhance the use of PyMOL in research and education.

  20. Final report on international comparison CCQM-K74: Nitrogen dioxide, 10 µmol/mol

    NASA Astrophysics Data System (ADS)

    Flores, Edgar; Idrees, Faraz; Moussay, Philippe; Viallon, Joële; Wielgosz, Robert; Fernández, Teresa; Ramírez, Sergio; Rojo, Andrés; Shinji, Uehara; Waldén, Jari; Sega, Michela; Sang-Hyub, Oh; Macé, Tatiana; Couret, Cedric; Qiao, Han; Smeulders, Damian; Guenther, Franklin R.; Thorn, William J., III; Tshilongo, James; Godwill Ntsasa, Napo; Štovcík, Viliam; Valková, Miroslava; Konopelko, Leonid; Gromova, Elena; Nieuwenkamp, Gerard; Wessel, Rob M.; Milton, Martin; Harling, Alice; Vargha, Gergely; Tuma, Dirk; Kohl, Anka; Schulz, Gert

    2012-01-01

    There is a high international priority attached to activities which reduce NOx in the atmosphere. The current level of permitted emissions is typically between 50 µmol/mol and 100 µmol/mol, but lower values are expected in the future. Currently, ambient air quality monitoring regulations also require the measurement of NOx mole fractions as low as 0.2 µmol/mol. The production of accurate standards at these levels of mole fractions requires either dilution of a stable higher concentration gas standard or production by a dynamic technique, for example one based on permeation tubes. The CCQM-K74 key comparison was designed to evaluate the level of comparability of National Metrology Institutes' measurement capabilities and standards for nitrogen dioxide (NO2) at a nominal mole fraction of 10 µmol/mol. The measurements of this key comparison took place from June 2009 to May 2010. Seventeen laboratories took part in this comparison coordinated by the BIPM and VSL. The key comparison reference value was based on BIPM measurement results, and the standard measurement uncertainty of the reference value was 0.042 µmol/mol. This key comparison demonstrated that the results of the majority of the participants agreed within limits of ±3% relative to the reference value. The results of only one laboratory lay significantly outside these limits. Likewise this comparison made clear that a full interpretation of the results of the comparison needed to take into account the presence of nitric acid (in the range 100 nmol/mol to 350 nmol/mol) in the cylinders circulated as part of the comparison, as well as the possible presence of nitric acid in the primary standards used by participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the

  1. The ExoMol database: Molecular line lists for exoplanet and other hot atmospheres

    NASA Astrophysics Data System (ADS)

    Tennyson, Jonathan; Yurchenko, Sergei N.; Al-Refaie, Ahmed F.; Barton, Emma J.; Chubb, Katy L.; Coles, Phillip A.; Diamantopoulou, S.; Gorman, Maire N.; Hill, Christian; Lam, Aden Z.; Lodi, Lorenzo; McKemmish, Laura K.; Na, Yueqi; Owens, Alec; Polyansky, Oleg L.; Rivlin, Tom; Sousa-Silva, Clara; Underwood, Daniel S.; Yachmenev, Andrey; Zak, Emil

    2016-09-01

    The ExoMol database (www.exomol.com) provides extensive line lists of molecular transitions which are valid over extended temperatures ranges. The status of the current release of the database is reviewed and a new data structure is specified. This structure augments the provision of energy levels (and hence transition frequencies) and Einstein $A$ coefficients with other key properties, including lifetimes of individual states, temperature-dependent cooling functions, Land\\'e $g$-factors, partition functions, cross sections, $k$-coefficients and transition dipoles with phase relations. Particular attention is paid to the treatment of pressure broadening parameters. The new data structure includes a definition file which provides the necessary information for utilities accessing ExoMol through its application programming interface (API). Prospects for the inclusion of new species into the database are discussed.

  2. Towards J/mol Accuracy for the Cohesive Energy of Solid Argon.

    PubMed

    Schwerdtfeger, Peter; Tonner, Ralf; Moyano, Gloria E; Pahl, Elke

    2016-09-26

    The cohesive energies of argon in its cubic and hexagonal closed packed structures are computed with an unprecedented accuracy of about 5 J mol(-1) (corresponding to 0.05 % of the total cohesive energy). The same relative accuracy with respect to experimental data is also found for the face-centered cubic lattice constant deviating by ca. 0.003 Å. This level of accuracy was enabled by using high-level theoretical, wave-function-based methods within a many-body decomposition of the interaction energy. Static contributions of two-, three-, and four-body fragments of the crystal are all individually converged to sub-J mol(-1) accuracy and complemented by harmonic and anharmonic vibrational corrections. Computational chemistry is thus achieving or even surpassing experimental accuracy for the solid-state rare gases.

  3. SigMol: repertoire of quorum sensing signaling molecules in prokaryotes.

    PubMed

    Rajput, Akanksha; Kaur, Karambir; Kumar, Manoj

    2016-01-04

    Quorum sensing is a widespread phenomenon in prokaryotes that helps them to communicate among themselves and with eukaryotes. It is driven through quorum sensing signaling molecules (QSSMs) in a density dependent manner that assists in numerous biological functions like biofilm formation, virulence factors secretion, swarming motility, bioluminescence, etc. Despite immense implications, dedicated resources of QSSMs are lacking. Therefore, we have developed SigMol (http://bioinfo.imtech.res.in/manojk/sigmol), a specialized repository of these molecules in prokaryotes. SigMol harbors information on QSSMs pertaining to different quorum sensing signaling systems namely acylated homoserine lactones (AHLs), diketopiperazines (DKPs), 4-hydroxy-2-alkylquinolines (HAQs), diffusible signal factors (DSFs), autoinducer-2 (AI-2) and others. Database contains 1382: entries of 182: unique signaling molecules from 215: organisms. It encompasses biological as well as chemical aspects of signaling molecules. Biological information includes genes, preliminary bioassays, identification assays and applications, while chemical detail comprises of IUPAC name, SMILES and structure. We have provided user-friendly browsing and searching facilities for easy data retrieval and comparison. We have gleaned information of diverse QSSMs reported in literature at a single platform 'SigMol'. This comprehensive resource will assist the scientific community in understanding intraspecies, interspecies or interkingdom networking and further help to unfold different facets of quorum sensing and related therapeutics.

  4. Azahar: a PyMOL plugin for construction, visualization and analysis of glycan molecules

    NASA Astrophysics Data System (ADS)

    Arroyuelo, Agustina; Vila, Jorge A.; Martin, Osvaldo A.

    2016-08-01

    Glycans are key molecules in many physiological and pathological processes. As with other molecules, like proteins, visualization of the 3D structures of glycans adds valuable information for understanding their biological function. Hence, here we introduce Azahar, a computing environment for the creation, visualization and analysis of glycan molecules. Azahar is implemented in Python and works as a plugin for the well known PyMOL package (Schrodinger in The PyMOL molecular graphics system, version 1.3r1, 2010). Besides the already available visualization and analysis options provided by PyMOL, Azahar includes 3 cartoon-like representations and tools for 3D structure caracterization such as a comformational search using a Monte Carlo with minimization routine and also tools to analyse single glycans or trajectories/ensembles including the calculation of radius of gyration, Ramachandran plots and hydrogen bonds. Azahar is freely available to download from http://www.pymolwiki.org/index.php/Azahar and the source code is available at https://github.com/agustinaarroyuelo/Azahar.

  5. Production of high concentration of L-lactic acid from cellobiose by thermophilic Bacillus coagulans WCP10-4.

    PubMed

    Ong, Shufen Angeline; Ng, Zhi Jian; Wu, Jin Chuan

    2016-07-01

    Thermophilic Bacillus coagulans WCP10-4 is found to be able to convert cellobiose to optically pure L-lactic acid. Its β-glucosidase activity is detected in whole cells (7.3 U/g dry cells) but not in culture medium, indicating the intracellular location of the enzyme. Its β-glucosidase activity is observed only when cultured using cellobiose as the sole carbon source, indicating that the expression of this enzyme is tightly regulated in cells. The enzyme is most active at 50 °C and pH 7.0. The supplement of external β-glucosidase during fermentation of cellobiose (106 g/l) by B. coagulans WCP10-4 increased the fermentation time from 21 to 23 h and decreased the lactic acid yield from 96.1 to 92.9 % compared to the control without β-glucosidase supplementation. B. coagulans WCP10-4 converted 200 g/l of cellobiose to 196.3 g/l of L-lactic acid at a yield of 97.8 % and a productivity of 7.01 g/l/h. This result shows that B. coagulans WCP10-4 is a highly efficient strain for converting cellobiose to L-lactic acid without the need of supplementing external β-glucosidases.

  6. ExoMol: Molecular Line List for Exoplanets and Other Atmospheres

    NASA Astrophysics Data System (ADS)

    Tennyson, Jonathan; Yurchenko, Sergei N.; Polyansky, Oleg

    2016-06-01

    The discovery of extrasolar planets is one of the major scientific advances of the last two decades. Thousands of planets have now been detected and astronomers are beginning to characterize their composition and physical characteristics. To do this requires a huge quantity of spectroscopic data most of which are not available from laboratory studies. The ExoMol project [1] is generating a comprehensive solution to this problem by providing spectroscopic data on all the molecular transitions of importance in the atmospheres of exoplanets. These data are widely applicable to other problems such studies on cool stars, brown dwarfs and circumstellar environments as well as industrial and technological problems on earth. ExoMol employs a mixture of first principles and empirically tuned quantum mechanical methods to compute comprehensive and very large rotation-vibration and rovibronic line lists. Results span a variety of closed (NaH, SiO, PN, NaCl, KCl, CS) and open (BeH, MgH, CaH, AlO, VO) shell diatomics to triatomics (HCN/HNC, SO_2, H_2S, H_3^+), tetratomics (H_2CO, PH_3, SO_3, H_2O_2), plus methane [2] and nitric acid [3]. This has led directly to the detection of new species in the atmospheres of exoplanets [4]. A new comprehensive data release has just been completed [5]. Progress on and future prospects of the project will be summarised. J. Tennyson, S. N. Yurchenko, Mon. Not. R. astr. Soc., 425, 21, 2012. S. N. Yurchenko, J. Tennyson, J. Bailey, M. D. J. Hollis, G Tinetti, Proc. Nat. Acad. Sci., 111, 9379, 2014. A. I. Pavlyuchko, S. N. Yurchenko, J. Tennyson, Mon. Not. R. astr. Soc., 452, 1702, 2015. A. Tsiaras et al, Astrophys. J., in press. J. Tennyson et al, J. Mol. Spectrosc., in press.

  7. MolProbity: all-atom structure validation for macromolecular crystallography.

    PubMed

    Chen, Vincent B; Arendall, W Bryan; Headd, Jeffrey J; Keedy, Daniel A; Immormino, Robert M; Kapral, Gary J; Murray, Laura W; Richardson, Jane S; Richardson, David C

    2010-01-01

    MolProbity is a structure-validation web service that provides broad-spectrum solidly based evaluation of model quality at both the global and local levels for both proteins and nucleic acids. It relies heavily on the power and sensitivity provided by optimized hydrogen placement and all-atom contact analysis, complemented by updated versions of covalent-geometry and torsion-angle criteria. Some of the local corrections can be performed automatically in MolProbity and all of the diagnostics are presented in chart and graphical forms that help guide manual rebuilding. X-ray crystallography provides a wealth of biologically important molecular data in the form of atomic three-dimensional structures of proteins, nucleic acids and increasingly large complexes in multiple forms and states. Advances in automation, in everything from crystallization to data collection to phasing to model building to refinement, have made solving a structure using crystallography easier than ever. However, despite these improvements, local errors that can affect biological interpretation are widespread at low resolution and even high-resolution structures nearly all contain at least a few local errors such as Ramachandran outliers, flipped branched protein side chains and incorrect sugar puckers. It is critical both for the crystallographer and for the end user that there are easy and reliable methods to diagnose and correct these sorts of errors in structures. MolProbity is the authors' contribution to helping solve this problem and this article reviews its general capabilities, reports on recent enhancements and usage, and presents evidence that the resulting improvements are now beneficially affecting the global database.

  8. Classification moléculaire du cancer du sein au Maroc

    PubMed Central

    Fouad, Abbass; Yousra, Akasbi; Kaoutar, Znati; Omar, El Mesbahi; Afaf, Amarti; Sanae, Bennis

    2012-01-01

    Introduction La classification moléculaire des cancers du sein basée sur l'expression génique puis sur le profil protéique a permis de distinguer cinq groupes moléculaires: luminal A, luminal B, Her2/neu, basal-like et non-classées. L'objectif de cette étude réalisée au CHU Hassan II de Fès est de classer 335 cancers du sein infiltrant en groupes moléculaires, puis de les corréler avec les caractéristiques clinicopathologiques. Méthodes Etude rétrospective étalée sur 45 mois, comportant 335 patientes colligées au CHU pour le diagnostic et le suivi. Les tumeurs sont analysées histologiquement et classées après une étude immunohistochimique en groupes: luminal A, luminal B, Her2+, basal-like et non-classées. Résultats 54.3% des tumeurs sont du groupe luminal A, 16% luminal B, 11.3% Her2+, 11.3% basal-like et 7% non-classées. Le groupe luminal A renferme le plus faible taux de grade III, d'emboles vasculaires ainsi que de métastases; alors que le groupe des non-classées et basal-like représentent un taux élevé de grade III, une faible proportion d'emboles vasculaires et d'envahissement ganglionnaire. Ces facteurs sont significativement élevés dans les groupes luminal B et Her2+ avec un taux de survie globale de 78% et 76% respectivement. Dans le groupe luminal A, la survie globale des patientes est élevée (87%) alors qu'elle n'est que de 49% dans le groupe des triples négatifs (basal-like et non-classés). Conclusion Le groupe luminal B est différent du luminal A et il est de pronostic péjoratif vis à vis du groupe Her2+. Les caractéristiques clinicopathologiques concordent avec le profil moléculaire donc devraient être pris en considération comme facteurs pronostiques. PMID:23396646

  9. Dick Mol. 'Sir Mammoth' leads charge to uncover Ice Age fossils.

    PubMed

    Stone, R

    2000-12-15

    Dick Mol may be an amateur, but he's had more success than most professionals in his chosen field of paleontology. As scientific coordinator of a major expedition that's gathering the remains of woolly mammoths and other Pleistocene fauna from Siberia's Taimyr Peninsula, this 45-year-old customs officer at Amsterdam airport has been featured in a documentary on the Discovery Channel and in a sequel to appear next March. The work has brought him international recognition for his studies on quaternary paleontology, the study of the Pleistocene and today's Holocene Epochs.

  10. Beneficial effects of Lagenaria siceraria (Mol.) Standley fruit epicarp in animal models.

    PubMed

    Deshpande, J R; Choudhari, A A; Mishra, M R; Meghre, V S; Wadodkar, S G; Dorle, A K

    2008-04-01

    Lagenaria siceraria (Mol.) Standley fruit (bottle gourd), a commonly used vegetable in India is described as cardiotonic and as a general tonic in Ayurveda. Keeping in view the presence of free radical scavenging activity in L. siceraria and involvement of free radicals in the development of various disorders, present studies were designed to evaluate the ethanolic extract of L. siceraria fruit against the disorders where free radicals play a major role in pathogenesis. The extract was found effective as hepatoprotective, antioxidant, antihyperglycemic, immunomodulatory, antihyperlipidemic and cardiotonic agent. The results showed that the radical scavenging capacity of L. siceraria fruit may be responsible for various biological activities studied.

  11. Moléculas orgánicas obtenidas en simulaciones experimentales del medio interestelar.

    NASA Astrophysics Data System (ADS)

    Muñoz-Caro, Guillermo Manuel

    Las nubes moleculares son regiones de formación de estrellas, con temperaturas cinéticas entre 10-50 K y densidades de 103-106 átomos cm-3. Su materia está formada por gas y polvo interestelar. Estas partículas de polvo están cubiertas por una fina capa de hielo, de unos 0.01 μm, que contiene H2O y a menudo CO, CO2, CH3OH y NH3. El hielo es presumiblemente irradiado por fotones ultravioleta y rayos cósmicos en las zonas poco profundas de las nubes moleculares y las regiones circunestelares. En un sistema de vacío, P ˜ 10-7 mbar, simulamos la deposición de hielo a partir de 10 K y la irradiación ultravioleta por medio de una lámpara de descarga de hidrógeno activada con microondas. La evolución del hielo se observa por medio de un espectrómetro infrarrojo. De este modo es posible determinar la composición del hielo observado en el medio interestelar y predecir la presencia de moléculas aún no detectadas en el espacio, que han sido producto del procesamiento del hielo en nuestros experimentos. También es posible calentar el sistema hasta temperatura ambiente para sublimar el hielo depositado. Cuando el hielo ha sido previamente irradiado, se observa un residuo compuesto por moléculas orgánicas complejas, algunas prebióticas, como varios ácidos carboxílicos, aminas, amidas, ésteres y en menor proporción moléculas heterocíclicas y aminoácidos. Algunas de estas moléculas podrían detectarse en estado gaseoso por medio de observaciones milimétricas y de radio. También podrían estar presentes en el polvo cometario, cuyo análisis químico está planeado por las misiones Stardust y Rosetta. Mientras tanto, nuestro grupo está llevando a cabo el análisis de partículas de polvo interplanetario (IDPs), algunas de las cuales pueden ser de origen cometario. Al igual que ocurre con los productos obtenidos por irradiación del hielo en nuestros experimentos, algunas IDPs son ricas en material orgánico que contiene oxígeno.

  12. Microbes at their best: first Mol Micro Meeting Würzburg.

    PubMed

    Böhm, Alex; Papenfort, Kai; Lopez, Daniel; Vogel, Jörg

    2011-11-01

    Founded on ground-breaking discoveries such as the operon model by Jacob and Monod more than 50 years ago, molecular microbiology is now one of the most vibrant disciplines of the life sciences. The first Mol Micro Meeting Würzburg ('M3W') hosted more than 160 scientists from 14 countries to exchange their latest ideas in this field of research. Divided into the four main sessions Gene Regulation, Pathogenesis, Microbial Cell Biology and Signalling, the conference provided insight into current advances and future goals and challenges.

  13. Swift J1822.3-1606: Optical spectroscopy of the counterpart candidates from the 10.4m GTC

    NASA Astrophysics Data System (ADS)

    de Ugarte Postigo, A.; Munoz-Darias, T.

    2011-07-01

    We have performed optical spectroscopy of the two objects (S1 and S2; ATEL #3496, #3502) present within the Swift/XRT error circle of the Soft Gamma-ray Repeater (SGR) candidate, Swift J1822.3-1606 (ATEL #3488, #3489, #3490, #3491, #3493, #3501, #3503). Observations were performed on July 20, 2011 using the OSIRIS spectrograph at the 10.4m Gran Telescopio de Canarias (GTC) telescope in La Palma, Spain.

  14. PyMOL mControl: Manipulating molecular visualization with mobile devices.

    PubMed

    Lam, Wendy W T; Siu, Shirley W I

    2017-01-02

    Viewing and manipulating three-dimensional (3D) structures in molecular graphics software are essential tasks for researchers and students to understand the functions of molecules. Currently, the way to manipulate a 3D molecular object is mainly based on mouse-and-keyboard control that is usually difficult and tedious to learn. While gesture-based and touch-based interactions are increasingly popular in interactive software systems, their suitability in handling molecular graphics has not yet been sufficiently explored. Here, we designed the gesture-based and touch-based interaction methods to manipulate virtual objects in PyMOL utilizing the motion and touch sensors in a mobile device. Three fundamental viewing controls-zooming, translation and rotation-and frequently used functions were implemented. Results from a pilot user study reveal that task performances on viewing controls using a mobile device are slightly reduced as compared to mouse-and-keyboard method. However, it is considered to be more suitable for oral presentations and equally suitable for education scenarios such as school classes. Overall, PyMOL mControl provides an alternative way to manipulate objects in molecular graphic software with new user experiences. The software is freely available at http://cbbio.cis.umac.mo/mcontrol.html. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(1):76-83, 2017.

  15. NEAR-INFRARED AND MILLIMETER-WAVELENGTH OBSERVATIONS OF Mol 160: A MASSIVE YOUNG PROTOSTELLAR CORE

    SciTech Connect

    Wolf-Chase, Grace; Smutko, Michael; Sherman, Reid; Harper, Doyal A.; Medford, Michael

    2012-02-01

    We have discovered two compact sources of shocked H{sub 2} 2.12 {mu}m emission coincident with Mol 160 (IRAS 23385+6053), a massive star-forming core thought to be a precursor to an ultracompact H II region. The 2.12 {mu}m sources lie within 2'' (0.05 pc) of a millimeter-wavelength continuum peak where the column density is {>=}10{sup 24} cm{sup -2}. We estimate that the ratio of molecular hydrogen luminosity to bolometric luminosity is >0.2%, indicating a high ratio of mechanical to radiant luminosity. CS J = 2{yields}1 and HCO{sup +} J = 1{yields}0 observations with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) indicate that the protostellar molecular core has a peculiar velocity of {approx}2 km s{sup -1} with respect to its parent molecular cloud. We also observed 95 GHz CH{sub 3}OH J = 8{yields}7 Class I maser emission from several locations within the core. Comparison with previous observations of 44 GHz CH{sub 3}OH maser emission shows that the maser sources have a high mean ratio of 95 GHz to 44 GHz intensity. Our observations strengthen the case that Mol 160 (IRAS 23385+6053) is a rapidly accreting massive protostellar system in a very early phase of its evolution.

  16. MolProbity: all-atom contacts and structure validation for proteins and nucleic acids

    PubMed Central

    Davis, Ian W.; Leaver-Fay, Andrew; Chen, Vincent B.; Block, Jeremy N.; Kapral, Gary J.; Wang, Xueyi; Murray, Laura W.; Arendall, W. Bryan; Snoeyink, Jack; Richardson, Jane S.; Richardson, David C.

    2007-01-01

    MolProbity is a general-purpose web server offering quality validation for 3D structures of proteins, nucleic acids and complexes. It provides detailed all-atom contact analysis of any steric problems within the molecules as well as updated dihedral-angle diagnostics, and it can calculate and display the H-bond and van der Waals contacts in the interfaces between components. An integral step in the process is the addition and full optimization of all hydrogen atoms, both polar and nonpolar. New analysis functions have been added for RNA, for interfaces, and for NMR ensembles. Additionally, both the web site and major component programs have been rewritten to improve speed, convenience, clarity and integration with other resources. MolProbity results are reported in multiple forms: as overall numeric scores, as lists or charts of local problems, as downloadable PDB and graphics files, and most notably as informative, manipulable 3D kinemage graphics shown online in the KiNG viewer. This service is available free to all users at http://molprobity.biochem.duke.edu. PMID:17452350

  17. MolProbity: all-atom contacts and structure validation for proteins and nucleic acids.

    PubMed

    Davis, Ian W; Leaver-Fay, Andrew; Chen, Vincent B; Block, Jeremy N; Kapral, Gary J; Wang, Xueyi; Murray, Laura W; Arendall, W Bryan; Snoeyink, Jack; Richardson, Jane S; Richardson, David C

    2007-07-01

    MolProbity is a general-purpose web server offering quality validation for 3D structures of proteins, nucleic acids and complexes. It provides detailed all-atom contact analysis of any steric problems within the molecules as well as updated dihedral-angle diagnostics, and it can calculate and display the H-bond and van der Waals contacts in the interfaces between components. An integral step in the process is the addition and full optimization of all hydrogen atoms, both polar and nonpolar. New analysis functions have been added for RNA, for interfaces, and for NMR ensembles. Additionally, both the web site and major component programs have been rewritten to improve speed, convenience, clarity and integration with other resources. MolProbity results are reported in multiple forms: as overall numeric scores, as lists or charts of local problems, as downloadable PDB and graphics files, and most notably as informative, manipulable 3D kinemage graphics shown online in the KiNG viewer. This service is available free to all users at http://molprobity.biochem.duke.edu.

  18. MolProbity’s Ultimate Rotamer-Library Distributions for Model Validation

    PubMed Central

    Hintze, Bradley J.; Lewis, Steven M.; Richardson, Jane S.; Richardson, David C.

    2016-01-01

    Here we describe the updated MolProbity rotamer-library distributions derived from an order-of-magnitude larger and more stringently quality-filtered dataset of about 8000 (vs. 500) protein chains, and we explain the resulting changes and improvements to model validation as seen by users. To include only sidechains with satisfactory justification for their given conformation, we added residue-specific filters for electron-density value and model-to-density fit. The combined new protocol retains a million residues of data, while cleaning up false-positive noise in the multi-χ datapoint distributions. It enables unambiguous characterization of conformational clusters nearly 1000-fold less frequent than the most common ones. We describe examples of local interactions that favor these rare conformations, including the role of authentic covalent bond-angle deviations in enabling presumably strained sidechain conformations. Further, along with favored and outlier, an allowed category (0.3% to 2.0% occurrence in reference data) has been added, analogous to Ramachandran validation categories. The new rotamer distributions are used for current rotamer validation in Mol-Probity and PHENIX, and for rotamer choice in PHENIX model-building and refinement. The multi-dimensional χ distributions and Top8000 reference dataset are freely available on GitHub. These rotamers are termed “ultimate” because data sampling and quality are now fully adequate for this task, and also because we believe the future of conformational validation should integrate sidechain with backbone criteria. PMID:27018641

  19. A novel protoapigenone analog RY10-4 induces breast cancer MCF-7 cell death through autophagy via the Akt/mTOR pathway

    SciTech Connect

    Zhang, Xuenong; Wei, Han; Liu, Ziwei; Yuan, Qianying; Wei, Anhua; Shi, Du; Yang, Xian; Ruan, Jinlan

    2013-07-15

    Protoapigenone is a unique flavonoid and enriched in many ferns, showing potent antitumor activity against a broad spectrum of human cancer cell lines. RY10-4, a modified version of protoapigenone, manifested better anti-proliferation activity in human breast cancer cell line MCF-7. The cytotoxicity of RY10-4 against MCF-7 cells is exhibited in both time- and concentration-dependent manners. Here we investigated a novel effect of RY10-4 mediated autophagy in autophagy defect MCF-7 cells. Employing immunofluorescence assay for microtubule-associated protein light-chain 3 (LC3), monodansylcadaverine staining, Western blotting analyses for LC3 and p62 as well as ultrastructural analysis by transmission electron microscopy, we showed that RY10-4 induced autophagy in MCF-7 cells but protoapigenone did not. Meanwhile, inhibition of autophagy by pharmacological and genetic approaches significantly increased the viability of RY10-4 treated cells, suggesting that the autophagy induced by RY10-4 played as a promotion mechanism for cell death. Further studies revealed that RY10-4 suppressed the activation of mTOR and p70S6K via the Akt/mTOR pathway. Our results provided new insights for the mechanism of RY10-4 induced cell death and the cause of RY10-4 showing better antitumor activity than protoapigenone, and supported further evidences for RY10-4 as a lead to design a promising antitumor agent. - Highlights: • We showed that RY10-4 induced autophagy in MCF-7 cells but protoapigenone did not. • Autophagy induced by RY10-4 played as a promotion mechanism for cell death. • RY10-4 induced autophagy in MCF-7 cell through the Akt/mTOR pathway. • We provided new insights for the mechanism of RY10-4 induced cell death.

  20. Molécule unique, nanotube de carbone et exaltation Raman

    NASA Astrophysics Data System (ADS)

    Débarre, A.; Jaffiol, R.; Julien, C.; Nutarelli, D.; Tchénio, P.

    2004-11-01

    La spectroscopie Raman fournit une analyse détaillée de la structure chimique d'un objet, à température ambiante. La section efficace de diffusion Raman d'un objet petit est souvent faible et son signal ne pourra être détecté sans utiliser un processus d'exaltation efficace de la diffusion. Cet article décrit quelques avancées dans le domaine de l'exaltation de surface de la diffusion Raman. Il est illustré par des résultats expérimentaux que nous avons obtenus sur des molécules uniques. Parfois, le signal de certains objets petits peut être détecté sans effet d'exaltation supplémentaire, comme le montre l'exemple de nanotubes remplis, dits peapods.

  1. W4 theory for computational thermochemistry : in pursuit of confident sub-kJ/mol predictions.

    SciTech Connect

    Karton, A.; Rabinovich, E.; Martin, J. M. L.; Ruscic, B.; Chemistry; Weizmann Institute of Science

    2006-01-01

    In an attempt to improve on our earlier W3 theory [A. D. Boese et al., J. Chem. Phys. 120, 4129 (2004)] we consider such refinements as more accurate estimates for the contribution of connected quadruple excitations ({cflx T}{sub 4}), inclusion of connected quintuple excitations ({cflx T}{sub 5}), diagonal Born-Oppenheimer corrections (DBOC), and improved basis set extrapolation procedures. Revised experimental data for validation purposes were obtained from the latest version of the Active Thermochemical Tables thermochemical network. The recent CCSDT(Q) method offers a cost-effective way of estimating {cflx T}{sub 4} but is insufficient by itself if the molecule exhibits some nondynamical correlation. The latter considerably slows down basis set convergence for {cflx T}{sub 4}, and anomalous basis set convergence in highly polar systems makes two-point extrapolation procedures unusable. However, we found that the CCSDTQ-CCSDT(Q) difference converges quite rapidly with the basis set, and that the formula 1.10[CCSDT(Q)/cc-pVTZ+CCSDTQ/cc-pVDZ-CCSDT(Q)/cc-pVDZ] offers a very reliable as well as fairly cost-effective estimate of the basis set limit {cflx T}{sub 4} contribution. The {cflx T}{sub 5} contribution converges very rapidly with the basis set, and even a simple double-zeta basis set appears to be adequate. The largest {cflx T}{sub 5} contribution found in the present work is on the order of 0.5 kcal/mol (for ozone). DBOCs are significant at the 0.1 kcal/mol level in hydride systems. Post-CCSD(T) contributions to the core-valence correlation energy are only significant at that level in systems with severe nondynamical correlation effects. Based on the accumulated experience, a new computational thermochemistry protocol for first- and second-row main-group systems, to be known as W4 theory, is proposed. Its computational cost is not insurmountably higher than that of the earlier W3 theory, while performance is markedly superior. Our W4 atomization energies for

  2. GTKDynamo: a PyMOL plug-in for QC/MM hybrid potential simulations

    PubMed Central

    Bachega, José Fernando R.; Timmers, Luís Fernando S.M.; Assirati, Lucas; Bachega, Leonardo R.; Field, Martin J.; Wymore, Troy

    2014-01-01

    Hybrid quantum chemical (QC)/molecular mechanical (MM) potentials are very powerful tools for molecular simulation. They are especially useful for studying processes in condensed phase systems, such as chemical reactions, that involve a relatively localized change in electronic structure and where the surrounding environment contributes to these changes but can be represented with more computationally efficient functional forms. Despite their utility, however, these potentials are not always straightforward to apply since the extent of significant electronic structure changes occurring in the condensed phase process may not be intuitively obvious. To facilitate their use we have developed an open-source graphical plug-in, GTKDynamo, that links the PyMOL visualization program and the pDynamo QC/MM simulation library. This article describes the implementation of GTKDynamo and its capabilities and illustrates its application to QC/MM simulations. PMID:24137667

  3. Automated Aufbau of antibody structures from given sequences using Macromoltek's SmrtMolAntibody.

    PubMed

    Berrondo, Monica; Kaufmann, Susana; Berrondo, Manuel

    2014-08-01

    This study was a part of the second antibody modeling assessment. The assessment is a blind study of the performance of multiple software programs used for antibody homology modeling. In the study, research groups were given sequences for 11 antibodies and asked to predict their corresponding structures. The results were measured using root-mean-square deviation (rmsd) between the submitted models and X-ray crystal structures. In 10 of 11 cases, the results using SmrtMolAntibody show good agreement between the submitted models and X-ray crystal structures. In the first stage, the average rmsd was 1.4 Å. Average rmsd values for the framework was 1.2 Å and for the H3 loop was 3.0 Å. In stage two, there was a slight improvement with an rmsd for the H3 loop of 2.9 Å.

  4. Moléculas orgánicas no-rígidas

    NASA Astrophysics Data System (ADS)

    Senent Díez, M. L.

    Se destaca la importancia del estudio espectroscópico ab initio de una serie de moléculas no-rígidas detectadas en el medio interestelar (acetona, dimetil-eter, etanol, metanol, metilamina, ldots), así como los últimos avances del desarrollo de la metodología para el tratamiento teórico de estas especies. Se describe, a modo de ejemplo, el análisis del espectro roto-torsional de la molécula de glicoaldehido que ha sido recientemente detectada en el centro Galáctico Sagitario B2 (N) [1]. Esta especie presenta dos movimientos de gran amplitud que interaccionan, descansan en el Infrarrojo Lejano y le confiere propiedades no-rígidas. La molécula puede existir en posiciones cis y trans y presenta cinco confórmeros estables, tres de simetría Cs (I, II y IV) y un doble mínimo trans de simetría C1 (III) . La conformación favorita, I, presenta simetría Cs y se estabiliza por la formación de un puente de hidrógeno entre los grupos OH y C=O. Los mínimos secundarios II, III, y IV se han determinado a 1278.2 cm-1 (trans, Cs), 1298.8 cm-1 (trans, C1) y 1865.2 cm-1 (cis, Cs) con cálculos MP4/cc-pVQZ que incluyen sustituciones triples. Para determinar que vibraciones interaccionan con las torsiones, se ha realizado un análisis armónico en los mínimos. Las frecuencias fundamentales armónicas correspondientes al mínimo I se han calculado en 213.4 cm-1 (torsión C-C) y 425.7 cm-1 (torsión OH). Es de esperar que tan sólo dos vibraciones, la flexión del grupo C-C-O y el aleteo del hidrógeno del grupo aldehídico puedan desplazar el espectro torsional de la molécula aislada. Para determinar el espectro torsional, se ha determinado la superficie de potencial en dos dimensiones mediante el cálculo ab initio de las geometrías y energías de 74 conformaciones seleccionadas. Estas últimas se han ajustado a un doble serie de Fourier. A partir de la PES y de los parámetros cinéticos del Hamiltoniano vibracional se han obtenido frecuencias e intensidades

  5. The atomistic structure of yttria stabilised zirconia at 6.7 mol%: an ab initio study.

    PubMed

    Parkes, Michael A; Tompsett, David A; d'Avezac, Mayeul; Offer, Gregory J; Brandon, Nigel P; Harrison, Nicholas M

    2016-11-16

    Yttria stabilized zirconia (YSZ) is an important oxide ion conductor used in solid oxide fuel cells, oxygen sensing devices, and for oxygen separation. Doping pure zirconia (ZrO2) with yttria (Y2O3) stabilizes the cubic structure against phonon induced distortions and this facilitates high oxide ion conductivity. The local atomic structure of the dopant is, however, not fully understood. X-ray and neutron diffraction experiments have established that, for dopant concentrations below 40 mol% Y2O3, no long range order is established. A variety of local structures have been suggested on the basis of theoretical and computational models of dopant energetics. These studies have been restricted by the difficulty of establishing force field models with predictive accuracy or exploring the large space of dopant configurations with first principles theory. In the current study a comprehensive search for all symmetry independent configurations (2857 candidates) is performed for 6.7 mol% YSZ modelled in a 2 × 2 × 2 periodic supercell using gradient corrected density functional theory. The lowest energy dopant structures are found to have oxygen vacancy pairs preferentially aligned along the 〈210〉 crystallographic direction in contrast to previous results which have suggested that orientation along the 〈111〉 orientation is favourable. Analysis of the defect structures suggests that the Y(3+)-Ovac interatomic separation is an important parameter for determining the relative configurational energies. Current force field models are found to be poor predictors of the lowest energy structures. It is suggested that the energies from a simple point charge model evaluated at unrelaxed geometries is actually a better descriptor of the energy ordering of dopant structures. Using these observations a pragmatic procedure for identifying low energy structures in more complicated material models is suggested. Calculation of the oxygen vacancy migration activation energies within

  6. Final report of key comparison APMP.QM-K53—comparison of gravimetric preparative capability with 100 μmol/mol of oxygen in nitrogen (bilateral comparison between NIM and KRISS)

    NASA Astrophysics Data System (ADS)

    Lee, Jeongsoon; Lee, JinBok; Moon, Dongmin; Han, Qiao; Zhou, Zeyi

    2015-01-01

    This bilateral comparison, which is traceable to CCQM-K53, was carried out to support NIM's capability for the preparation of stable gas species in nitrogen. The target amount of substance was 100 μmol/mol of oxygen in nitrogen, which was prepared gravimetrically by the participant. The comparison showed that the NIM and KRISS gravimetric values were consistent with each other to within the expanded uncertainty of 0.200 μmol/mol. Therefore the comparison is well linked to the CCQM-K53 and offers a gravimetric preparation capability of oxygen in nitrogen at a level of 100 μmol/mol to the participant. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. The large scale in-situ PRACLAY heater and seal tests in URL HADES, Mol, Belgium

    SciTech Connect

    Xiangling Li; Guangjing Chen; Verstricht, Jan; Van Marcke, Philippe; Troullinos, Ioannis

    2013-07-01

    In Belgium, the URL HADES was constructed in the Boom Clay formation at the Mol site to investigate the feasibility of geological disposal in a clay formation. Since 1995, the URL R and D programme has focused on large scale demonstration tests like the PRACLAY Heater and Seal tests. The main objective of the Heater Test is to demonstrate that the thermal load generated by the heat-emitting waste will not jeopardise the safety functions of the host rock. The primary objective of the Seal Test is to provide suitable hydraulic boundary conditions for the Heater Test. The Seal Test also provides an opportunity to investigate the in-situ behaviour of a bentonite-based EBS. The PRACLAY gallery was constructed in 2007 and the hydraulic seal was installed in 2010. The bentonite is hydrated both naturally and artificially. The swelling, total pressure and pore pressure of the bentonite are continuously measured and analysed by numerical simulations to get a better understanding of this hydration processes. The timing of switching on the heater depends on the progress of the bentonite hydration, as a sufficient seal swelling is needed to fulfill its role. A set of conditions to be met for the heater switch-on and its schedule will be given. (authors)

  8. Using the PyMOL application to reinforce visual understanding of protein structure.

    PubMed

    Rigsby, Rachel E; Parker, Alison B

    2016-09-10

    Visualization of chemical concepts can be challenging for many students. This is arguably a critical skill for beginning students of biochemistry to develop, since new information is often presented visually in the form of textbook figures. It is recommended that visual literacy be explicitly taught in the classroom rather than assuming that students will develop this skill on their own.  The activity described here is designed to assist students in their development of understanding of basic representations of protein three-dimensional structure as well as various types of ligands (small molecules, ions) through the use of the iPad application PyMOL.  It has been used as a laboratory exercise but can also be used in a typical 50-minute class period with a portion of the activity assigned as homework. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):433-437, 2016.

  9. molSimplify: A toolkit for automating discovery in inorganic chemistry.

    PubMed

    Ioannidis, Efthymios I; Gani, Terry Z H; Kulik, Heather J

    2016-08-15

    We present an automated, open source toolkit for the first-principles screening and discovery of new inorganic molecules and intermolecular complexes. Challenges remain in the automatic generation of candidate inorganic molecule structures due to the high variability in coordination and bonding, which we overcome through a divide-and-conquer tactic that flexibly combines force-field preoptimization of organic fragments with alignment to first-principles-trained metal-ligand distances. Exploration of chemical space is enabled through random generation of ligands and intermolecular complexes from large chemical databases. We validate the generated structures with the root mean squared (RMS) gradients evaluated from density functional theory (DFT), which are around 0.02 Ha/au across a large 150 molecule test set. Comparison of molSimplify results to full optimization with the universal force field reveals that RMS DFT gradients are improved by 40%. Seamless generation of input files, preparation and execution of electronic structure calculations, and post-processing for each generated structure aids interpretation of underlying chemical and energetic trends. © 2016 Wiley Periodicals, Inc.

  10. MIRADAS: The Multi-Object R=22K Near-IR Spectropolarimeter for the 10.4-meter GTC

    NASA Astrophysics Data System (ADS)

    Eikenberry, Stephen S.; MIRADAS Consortium

    2016-01-01

    The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS), a near-infrared multi-object echelle spectrograph operating at spectral resolution R=22,000 over the 1-2.5µm bandpass, is being developed by an international consosrtium for the 10.4-meter Gran Telescopio Canarias (GTC). The MIRADAS consortium includes the University of Florida, Universidad de Barcelona, Universidad Complutense de Madrid, Instituto de Astrofísica de Canarias, as well as industrial partners in the US and Europe. MIRADAS completed its Final Design Review in mid-2015, and is currently undergoing fabrication, with planned first light in 2018/2019. In this paper, we review the overall science drivers and system design for MIRADAS, including key technologies such as cryogenic robotic probe arms, macroslicer mini-IFUs, full Stokes polarimetry, and a highly flexible observing configuration.

  11. Optical observations of Swift J1822.3-1606 with the 10.4m Gran Telescopio Canarias

    NASA Astrophysics Data System (ADS)

    Rea, N.; Mignani, R. P.; Israel, G. L.; Esposi, P.

    2011-07-01

    We observed the field of the new Soft Gamma-ray Repeater (SGR), Swift J1822.3-1606 (Cummings et al., Atel #3488) with the 10.4m Gran Telescopio Canarias (GranTeCan). Images have been taken with the OSIRIS camera, a two-chip CCD with a nominal 7.8'x7.8' arcmin field of view and a pixel size of 0.125". Observations have been taken in the z-Sloan-band on 2011 July 21st (unfortunately in bright lunar time, with a large sky background and a seeing ranging from 1-2.5") with exposure times of 54-108s.

  12. Geophysical data from boreholes DM1, DM2, DM3, and DM3a, New Hydraulic Fracturing Facility, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    SciTech Connect

    Haase, C S

    1987-03-01

    A comprehensive suite of geophysical logs was obtained from four deep monitoring boreholes at the New Hydrofracture Facility. The logging was an attempt to obtain stratigraphic, structural, and hydrologic information on the subsurface environment surrounding the hydrofracture facility. Logs obtained include caliper, gamma, neutron, density, single-point resistance, long- and short-normal resistivity, spontaneous potential, temperature, acoustic velocity, variable density, and borehole televiewer. Analysis and interpretation of the geophysical logs allowed the stratigraphic section at the facility to be determined and, by comparison with calibrated geophysical logs from borehole ORNL-Joy No. 2, allowed detailed inferences to be drawn about rock types and properties at the hydrofracture facility. Porosity values measured from the logs for Conasauga Group strata, as well as permeability values inferred from the logs, are low. Several intervals of apparently greater permeability, associated primarily with limestone-rich portions of the Maryville Limestone and sandstone-rich portions of the Rome Formation, were noted. Numerous fractures were identified by using several logs in combination. No one geophysical log was reliable for fracture identification although the acoustic-televiewer log appeared to have the greatest success. In addition to their characterization of subsurface conditions in the vicinity of the hydrofracture facility, the geophysical logs provided data on the extent of hydraulic fractures. Anomalies on single-point resistance logs that corresponded to prominent fractures identified on televiewer logs indicate intervals affected by hydraulic fractures associated with waste injection at the New Hydrofracture Facility. 14 refs.

  13. ExoMol molecular line lists - XIII. The spectrum of CaO

    NASA Astrophysics Data System (ADS)

    Yurchenko, Sergei N.; Blissett, Audra; Asari, Usama; Vasilios, Marcus; Hill, Christian; Tennyson, Jonathan

    2016-03-01

    An accurate line list for calcium oxide is presented covering transitions between all bound ro-vibronic levels from the five lowest electronic states X 1Σ+, A' 1Π, A 1Σ+, a 3Π, and b 3Σ+. The ro-vibronic energies and corresponding wavefunctions were obtained by solving the fully coupled Schrödinger equation. Ab initio potential energy, spin-orbit, and electronic angular momentum curves were refined by fitting to the experimental frequencies and experimentally derived energies available in the literature. Using our refined model we could (1) reassign the vibronic states for a large portion of the experimentally derived energies (van Groenendael A., Tudorie M., Focsa C., Pinchemel B., Bernath P. F., 2005, J. Mol. Spectrosc., 234, 255), (2) extended this list of energies to J = 61-118 and (3) suggest a new description of the resonances from the A 1Σ+-X 1Σ+ system. We used high level ab initio electric dipole moments reported previously (Khalil H., Brites V., Le Quere F., Leonard C., 2011, Chem. Phys., 386, 50) to compute the Einstein A coefficients. Our work is the first fully coupled description of this system. Our line list is the most complete catalogue of spectroscopic transitions available for 40Ca16O and is applicable for temperatures up to at least 5000 K. CaO has yet to be observed astronomically but its transitions are characterized by being particularly strong which should facilitate its detection. The CaO line list is made available in an electronic form as supplementary data to this article and at www.exomol.com.

  14. Dietary fibre concentrate from Chilean algarrobo (Prosopis chilensis (Mol.) Stuntz) pods: purification and characterization.

    PubMed

    Estévez, Ana María; Figuerola, Fernando; Bernuy, Enrique; Sáenz, Carmen

    2014-12-01

    Prosopis species are generally fast-growing, drought-resistant, nitrogen-fixing trees or shrubs. Fruits of Prosopis spp are indehiscent pods, where pericarp is formed by the epicarp, light brown in colour, and fibrous nature; the mesocarp known as pulp, which is rich in sugars; and the endocarp. The aim of this work was to obtain a fibre concentrate from the pods of Prosopis chilensis Mol. (Stuntz) and to determine the chemical, physical, and technological properties of the pod flour (PF) and of a fibre concentrate or pod purified flour (PPF). Acetone, ethanol, and water at different conditions of time and temperature were used in the purification process. PF showed 53.7 g/100 g of total sugar content, 4.2 g/100 g of reducing sugar content, 41.8 g/100 g of total dietary fibre, 35.8 g/100 g of insoluble fibre, and 6.0 g/100 g of soluble fibre content. The PPF has a total sugar content of 3.8 g/100 g, reducing sugar content of 2.2 g/100 g, total dietary fibre content of 80.8 g/100 g, insoluble fibre content of 75.1 g/100 g, and soluble fibre content of 5.7 g/100 g. The scanning electron microscopy analysis showed the existence of voids in the structure of PPF flour, which reveals the efficiency of the purification process with a high decrease in the total sugar content.

  15. KVFinder: steered identification of protein cavities as a PyMOL plugin

    PubMed Central

    2014-01-01

    Background The characterization of protein binding sites is a major challenge in computational biology. Proteins interact with a wide variety of molecules and understanding of such complex interactions is essential to gain deeper knowledge of protein function. Shape complementarity is known to be important in determining protein-ligand interactions. Furthermore, these protein structural features have been shown to be useful in assisting medicinal chemists during lead discovery and optimization. Results We developed KVFinder, a highly versatile and easy-to-use tool for cavity prospection and spatial characterization. KVFinder is a geometry-based method that has an innovative customization of the search space. This feature provides the possibility of cavity segmentation, which alongside with the large set of customizable parameters, allows detailed cavity analyses. Although the main focus of KVFinder is the steered prospection of cavities, we tested it against a benchmark dataset of 198 known drug targets in order to validate our software and compare it with some of the largely accepted methods. Using the one click mode, we performed better than most of the other methods, staying behind only of hybrid prospection methods. When using just one of KVFinder’s customizable features, we were able to outperform all other compared methods. KVFinder is also user friendly, as it is available as a PyMOL plugin, or command-line version. Conclusion KVFinder presents novel usability features, granting full customizable and highly detailed cavity prospection on proteins, alongside with a friendly graphical interface. KVFinder is freely available on http://lnbio.cnpem.br/bioinformatics/main/software/. PMID:24938294

  16. Gene-trap mutagenesis using Mol/MSM-1 embryonic stem cells from MSM/Ms mice.

    PubMed

    Nakahara, Mai; Tateyama, Hiroki; Araki, Masatake; Nakagata, Naomi; Yamamura, Ken-ichi; Araki, Kimi

    2013-06-01

    The MSM/Ms strain is derived from the Japanese wild mouse Mus musculus molossinus and displays characteristics not observed in common laboratory strains. Functional genomic analyses using genetically engineered MSM/Ms mice will reveal novel phenotypes and gene functions/interactions. We previously reported the establishment of a germline-competent embryonic stem (ES) cell line, Mol/MSM-1, from the MSM/Ms strain. To analyze its usefulness for insertional mutagenesis, we performed gene-trapping using these cells. In the present study, we compared the gene-trap events between Mol/MSM-1 and a conventional ES cell line, KTPU8, derived from the F1 progeny of a C57BL/6 × CBA cross. We introduced a promoter-trap vector carrying the promoterless β-galactosidase/neomycin-resistance fusion gene into Mol/MSM-1 and KTPU8 cells, isolated clones, and identified the trapped genes by rapid amplification of cDNA 5'-ends (5'-RACE), inverse PCR, or plasmid rescue. Unexpectedly, the success rate of 5'-RACE in Mol/MSM trap clones was 47 %, lower than the 87 % observed in KTPU8 clones. Genomic analysis of the 5'-RACE-failed clones revealed that most had trapped ribosomal RNA gene regions. The percentage of ribosomal RNA region trap clones was 41 % in Mol/MSM-1 cells, but less than 10 % in KTPU8 cells. However, within the Mol/MSM-1 5'-RACE-successful clones, the trapping frequency of annotated genes, the chromosomal distribution of vector insertions, the frequency of integration into an intron around the start codon-containing exon, and the functional spectrum of trapped genes were comparable to those in KTPU8 cells. By selecting 5'-RACE-successful clones, it is possible to perform gene-trapping efficiently using Mol/MSM-1 ES cells and promoter-trap vectors.

  17. International comparison CCQM-K82: methane in air at ambient level (1800 to 2200) nmol/mol

    NASA Astrophysics Data System (ADS)

    Flores, Edgar; Viallon, Joële; Choteau, Tiphaine; Moussay, Philippe; Wielgosz, Robert I.; Kang, Namgoo; Kim, Byung Moon; Zalewska, Ewelina; H van der Veen, Adriaan (A. M.; Konopelko, Leonid; Wu, Hai; Han, Qiao; Rhoderick, George; Guenther, Franklin R.; Watanabe, Takuro; Shimosaka, Takuya; Kato, Kenji; Hall, Brad; Brewer, Paul

    2015-01-01

    The CCQM-K82 comparison was designed to evaluate the degrees of equivalence of NMI capabilities for methane in air primary reference mixtures in the range (1800 to 2200) nmol/mol. The balance gas for the standards was either scrubbed dry real air or synthetic air. CH4 in air standards have been produced by a number of laboratories for many years, with more recent developments focused on standards at atmospheric measurement concentrations and aimed at obtaining agreement between independently produced standards. A comparison of the differences in primary gas standards for methane in air was previously performed in 2003 (CCQM-P41 Greenhouse gases. 1 and 2) with a standard deviation of results around the reference value of 30 nmol/mol and 10 nmol/mol for a more limited set of standards. This can be contrasted with the level of agreement required from field laboratories routinely measuring atmospheric methane levels, set by Data Quality Objectives (DQO) established by the World Meteorological Organization (WMO) to reflect the scientifically desirable level of compatibility for CH4 measurements at the global scale, currently set at 2 nmol/mol (1 sigma). The measurements of this key comparison took place from May 2012 to June 2012. Eight laboratories took part in this comparison coordinated by the BIPM and NIST. Key comparison reference values were calculated based on Cavity Ring Down Spectroscopy Measurements performed at the BIPM, combined with participant's gravimetric values to identify a consistent set of standards. Regression analysis allowed predicted values for each standard to be calculated which acted as the KCRVs. In this comparison reported standard uncertainties by participants ranged from 0.50 nmol/mol to 2.4 nmol/mol and the uncertainties of individual KCRVs ranged from 0.68 nmol/mol to 0.71 nmol/mol. The standard deviation of the ensemble of standards about the KCRV value was 1.70 nmol/mol. This represents a greater than tenfold improvement in the level

  18. Analyse de la dynamique temporelle d'une molécule unique en matrice sol-gel

    NASA Astrophysics Data System (ADS)

    Débarre, A.; Tchénio, P.; Azoulay, J.; Jaf Iol, R.; Nutarelli, D.

    2002-06-01

    L'un des enjeux des études de molécules uniques est de développer des sondes très locales d'un environnement donné. De telles informations ne sont pas accessibles dans les expériences classiques où de nombreuses molécules sont détectées simultanément. Celles-ci ne permettent de déterminer que la valeur moyenne de la distribution d'un paramètre. Parmi les paramètres temporels, la durée de vie des états excités atteints par la molécule occupe une place particulière. Ce paramètre, qui est lié aux propriétés quantiques de la molécule peut varier considérablement si des transferts d'énergie s'établissent entre la molécule et son environnement immédiat. Un autre exemple est la mesure du nombre total de photons émis par la molécule avant qu'elle n'émette plus ( photoblanchiment ). L'arrêt définitif de l'émission est très directement lié aux interactions lumineuses ou collisionnelles que la molécule subit dans les états excités où elle est portée. Cet article décrit d'une part le dispositif expérimental qui a été développé pour déterminer plusieurs paramètres temporels sur la même molécule, et d'autre part les premiers résultats acquis dans des matériaux sol-gels dopés par des molécules dérivées du pérylène[1].

  19. Phase transformation and wear studies of plasma sprayed yttria stabilized zirconia coatings containing various mol% of yttria

    SciTech Connect

    Aruna, S.T. Balaji, N.; Rajam, K.S.

    2011-07-15

    Plasma sprayable grade zirconia powders doped with various mol% of yttria (0, 2, 3, 4, 6, 8 and 12 mol%) were synthesized by a chemical co-precipitation route. The coprecipitation conditions were adjusted such that the powders possessed good flowability in the as calcined condition and thus avoiding the agglomeration step like spray drying. Identical plasma spray parameters were used for plasma spraying all the powders on stainless steel plates. The powders and plasma sprayed coatings were characterized by X-ray diffractometry, Scanning Electron Microscopy and Raman spectroscopy. Zirconia powders are susceptible to phase transformations when subjected to very high temperatures during plasma spraying and XRD is insensitive to the presence of some non crystalline phases and hence Raman spectroscopy was used as an important tool. The microstructure of the plasma sprayed coatings showed a bimodal distribution containing fully melted and unmelted zones. The microhardness and wear resistance of the plasma sprayed coatings were determined. Among the plasma sprayed coatings, 3 mol% yttria stabilized zirconia coating containing pure tetragonal zirconia showed the highest wear resistance. - Research Highlights: {yields} Preparation plasma sprayable YSZ powders without any agglomeration process and plasma spraying {yields} Phase transformation studies of plasma sprayed YSZ coatings by XRD and Raman spectroscopy {yields} Microstructure of the plasma sprayed coatings exhibited bimodal distribution {yields} Plasma sprayed 3 mol% YSZ coating exhibited the highest wear resistance {yields} Higher wear resistance is due to the higher fracture toughness of tetragonal 3 mol% YSZ phase.

  20. Long-pulse operation of a 0.5 MW TE{sub 10.4} gyrotron at 140 GHz

    SciTech Connect

    Dammertz, G.; Iatrou, C.T.; Kuntze, M.; Moebius, A.; Piosczyk, B.; Braz, O.; Thumm, M. |

    1996-06-01

    Gyrotron oscillators have proven to be highly efficient sources of coherent mm-wave radiation. They have been used successfully for electron cyclotron resonance heating (ECRH) experiments and electron cyclotron diagnostics (ECD) of plasma fusion for some time. Due to the localized energy deposition, the temperature profile can be modified and the stability of the plasma can be improved. Here, the operation features of a TE{sub 10.4}-mode gyrotron oscillator with a quasi-optical mode converter and a single-stage depressed collector at 140 GHz with an output power of 500 kW in long pulses of 0.2 s are presented. Measurements on long-pulse operation of the tube are described in detail, and the significant differences between short- and long-pulse operation concerning efficiency and output power are pointed out. The variation of frequency during a pulse and an irreversible frequency shift during long-pulse operation were measured and are discussed with respect to gyrotron design.

  1. MEGARA: the future optical IFU and multi-object spectrograph for the 10.4m GTC telescope

    NASA Astrophysics Data System (ADS)

    Gil de Paz, A.; Carrasco, E.; Gallego, J.; Sánchez, F. M.; Vílchez Medina, J. M.; García-Vargas, M. L.; Arrillaga, X.; Carrera, M. A.; Castillo-Morales, A.; Castillo-Domínguez, E.; Cedazo, R.; Eliche-Moral, C.; Ferrusca, D.; González-Guardia, E.; Maldonado, M.; Marino, R. A.; Martínez-Delgado, I.; Morales Durán, I.; Mújica, E.; Pascual, S.; Pérez-Calpena, A.; Sánchez-Penim, A.; Sánchez-Blanco, E.; Serena, F.; Tulloch, S.; Villar, V.; Zamorano, J.; Barrado y Naváscues, D.; Bertone, E.; Cardiel, N.; Cava, A.; Cenarro, J.; Chávez, M.; García, M.; Guichard, J.; Gúzman, R.; Herrero, A.; Huélamo, N.; Hughes, D.; Iglesias, J.; Jiménez-Vicente, J.; Aguerri, A. L.; Mayya, D.; Méndez-Abreu, J. M.; Mollá, M.; Muñoz-Tuñón, C.; Peimbert, S.; Peimbert, M.; Pérez-González, P. G.; Pérez Montero, E.; Rodríguez, M.; Rodríguez-Espinosa, J. M.; Rodríguez-Merino, L.; Rosa, D.; Sánchez-Almeida, J.; Sánchez Contreras, C.; Sánchez-Blázquez, Patricia; Sánchez, S.; Sarajedini, A.; Silich, S.; Simón, S.; Tenorio-Tagle, G.; Terlevich, E.; Terlevich, R.; Trujillo, I.; Tsamis, Y.; Vega, O.

    2012-09-01

    In these proceedings we give a summary of the characteristics and current status of the MEGARA instrument, the future optical IFU and MOS for the 10.4-m Gran Telescopio Canarias (GTC). MEGARA is being built by a Consortium of public research institutions led by the Universidad Complutense de Madrid (UCM, Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain). The MEGARA IFU includes two different fiber bundles, one called LCB (Large Compact Bundle) with a field-of-view of 12.5×11.3 arcsec2 and a spaxel size of 0.62 arcsec yielding spectral resolutions between R=6,800-17,000 and another one called SCB (Small Compact Bundle) covering 8.5×6.7 arcsec2 with hexagonally-shaped and packed 0.42-arcsec spaxels and resolutions R=8,000-20,000. The MOS component allows observing up to 100 targets in 3.5×3.5 arcmin2. Both the IFU bundles and the set of 100 robotic positioners of the MOS will be placed at one of the GTC Folded-Cass foci while the spectrographs (one in the case of the MEGARA-Basic concept) will be placed at the Nasmyth platform. On March 2012 MEGARA passed the Preliminary Design Review and its first light is expected to take place at the end of 2015.

  2. Orientation photoinduite de nouvelles molécules pour l'optique non linéaire

    NASA Astrophysics Data System (ADS)

    Ngan, N. T. K.; Dumont, M.

    2002-06-01

    Dans les films de polymères utilisés pour les composants de télécommunication, l'orientation photoinduite de molécules de colorants permet de réaliser une biréfringence ou une non centrosymétrie (X^{(2)}). Le mécanisme d'orientation comporte un pompage optique sélectif (“hole buming angulaire”), suivi, soit d'une photodégradation, soit d'un retour à l'état initial, accompagné d'une rotation (“redistribution angulaire”). Seul ce second cas conduit à une orientation importante, par accumulation des molécules dans la direction la moins pompée. C'est le cas des molécules photoisomérisables de façon réversible, tels les azobenzènes. Nous présentons ici une nouvelle molécule azoïque octupolaire qui est un excellent candidat pour l'orientation tout-optique.

  3. Protective effect of Lagenaria siceraria (Mol) against membrane-bound enzyme alterations in isoproterenol-induced cardiac damage in rats.

    PubMed

    Vijayakumar, M; Selvi, V; Krishnakumari, S

    2012-01-01

    This study was aimed at evaluating the preventive role of the ethanolic extract of Lagenaria siceraria (Mol) fruit on membrane-bound enzymes, such as sodium potassium-dependent adenosine triphosphatase (Na(+)/K(+) ATPase), calcium-dependent adenosine triphosphatase (Ca(2+) ATPase) and magnesium-dependent adenosine triphosphatase (Mg(2+) ATPase) on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. Male albino Wistar rats were pretreated with the ethanolic extract of L. siceraria (Mol) fruit (125, 250 and 500 mg kg(-1) body weight) for a period of 30 days. After the treatment period, ISO (85mg kg(-1) body weight) was subcutaneously injected into rats at 24-h intervals for 2 days. ISO-induced rats showed a significant (p < 0.05) decrease in the activity of Na(+)/K(+) ATPase and an increase in the activities of Ca(2+) and Mg(2+) ATPases in the heart tissues. Pre-treatment with the ethanolic extract of L. siceraria (Mol) fruit for a period of 30 days exhibited a significant (p < 0.05) effect in ISO-induced rats. Thus, our study shows that the ethanolic extract of L. siceraria (Mol) fruit has membrane-stabilising role in ISO-induced MI in rats.

  4. [The nuclear matrix proteins (mol. mass 38 and 50 kDa) are transported by chromosomes in mitosis].

    PubMed

    Murasheva, M I; Chentsov, Iu S

    2010-01-01

    It was shown by immunofluorescence method that serum M68 and serum K43 from patients with autoimmune disease stain interphase nuclei and periphery of mitotic chromosomes of pig kidney cells. Western blotting reveals the polypeptide with mol. mass of 50 kDa in serum M68, and the polypeptide with mol. mass of 38 kDa in serum K43. In the nuclear protein matrix, the antibodies to protein with mol. mass of 38 kDa stained only nucleolar periphery, while the antibodies to the protein with mol. mass of 50 kDa stained both the nucleolar periphery and all the interphase nucleus. It shows that among all components of nuclear protein matrix (lamina, internuclear network, residual nucleoli) only nucleolar periphery contains the 38 kDa protein, while the 50 kDa protein is a part of residual nucleolar periphery and takes part in nuclear protein network formation. In the interphase cells, both proteins were in situ localized in the nuclei, but one of them with mol. mass of 50 kDa was in the form of small clearly outlined granules, while the other (38 kDa) was in the form of small bright granules against the background of diffusely stained nuclei. Both proteins were also revealed as continuous ring around nucleolar periphery. During all mitotic stages, the 50 kDa protein was seen on the chromosomal periphery as a cover, and the 38 kDa protein formed separate fragments and granules around them. After nuclear and chromosome decondensation induced by hypotonic treatment, both antibodies stain interphase nuclei in diffuse manner, but in mitotic cells they stained the surface of the swollen chromosomes. The polypeptide with mol. mass of 50 kDa maintained strong connection with chromosome periphery both in norm and under condition of decondensation induced by hypotonic treatment and at subsequent recondensation in isotonic medium. In contrast, the protein with mol. mass of 38 kDa partially lost the contact with a chromosome during recondensation appearing also in the form of granules in

  5. Compositional study of asteroids in the Erigone collisional family using visible spectroscopy at the 10.4m GTC

    NASA Astrophysics Data System (ADS)

    Morate, David; de León, Julia; De Prá, Mário; Licandro, Javier; Cabrera-Lavers, Antonio; Campins, Humberto; Pinilla-Alonso, Noemí; Alí-Lagoa, Víctor

    2015-11-01

    Asteroid families are formed by the fragments produced by the disruption of a common parent body (Bendjoya & Zappalà 2002). Primitive asteroids in the solar system are believed to have undergone less thermal processing than the S-complex asteroids. Thus, study of primitive asteroid families provides information about the solar system formation period. The Erigone collisional family, together with other three families (Polana, Clarissa and Sulamitis), are believed to be the origin of the two primitive Near-Earth asteroids that are the main targets of the NASA’s OSIRIS-REx ((101955) Bennu) and JAXA’s Hayabusa 2 ((162173) 1999 JU3) missions (Campins et al. 2010; Campins et al. 2013; Lauretta et al. 2010; Tsuda et al. 2013). These spacecrafts will visit the asteroids, and a sample of their surface material will be returned to Earth. Understanding of the families that are considered potential sources will enhance the scientific return of the missions. The main goal of the work presented here is to characterize the Erigone collisional family. Asteroid (163) Erigone has been classified as a primitive object (Bus 1999; Bus & Binzel 2002), and we expect the members of this family to be consistent with the spectral type of the parent body. We have obtained visible spectra (0.5-0.9 μm) for 101 members of the Erigone family, using the OSIRIS instrument at the 10.4m Gran Telescopio Canarias. We performed a taxonomical classification of these asteroids, finding that the number of primitive objects in our sample is in agreement with the hypothesis of a common parent body. In addition, we have found a significant fraction of asteroids in our sample that present evidences of aqueous alteration. Study of aqueous alterations is important, as it can give information on the heating processes of the early Solar System, and for the associated astrobiological implications (it has been suggested that the Earth’s present water supply was brought here by asteroids, instead of comets

  6. Stability assessment of gas mixtures containing terpenes at nominal 5 nmol/mol contained in treated aluminum gas cylinders.

    PubMed

    Rhoderick, George C

    2010-10-01

    Studies of climate change increasingly recognize the diverse influences exerted by terpenes in the atmosphere, including roles in particulates, ozone formation, and their oxidizing potential. Measurements of key terpenes suggest atmospheric concentrations ranging from low pmol/mol (parts per trillion) to nmol/mol (parts per billion), depending on location and compound. To accurately establish concentration trends, assess the role of terpenes in atmospheric chemistry, and relate measurement records from many laboratories and researchers, it is essential to have good calibration standards. The feasibility of preparing well-characterized, stable gas cylinder standards for terpenes at the nmol/mol level is not yet well established. Several of the world's National Metrology Institutes (NMIs) are researching the feasibility of developing primary and secondary reference gas standards at the nmol/mol level for terpenes. The US NMI, the National Institute of Standards and Technology, has prepared several nmol/mol mixtures, in treated aluminum gas cylinders, containing terpenes in dry nitrogen at nominal 5 nmol/mol for stability studies. Overall, 11 terpenes were studied for stability. An initial gas mixture containing nine terpenes, one oxygenate, and six aromatic compounds, including benzene as an internal standard, was prepared. Results for four of the nine terpenes in this initial mixture indicate stability in these treated aluminum gas cylinders for over 6 months and project long term (years) stability. Interesting results were seen for beta-pinene, which when using a linear equation rate decline predicts that it will reach a zero concentration level at day 416. At the same time, increases in alpha-pinene, D: -limonene (R-(+)-limonene), and p-cymene were observed, including camphene, a terpene not prepared in the gas mixture, indicating a chemical transformation of beta-pinene to these species. Additional mixtures containing combination of either alpha-pinene, camphor

  7. Inducible and constitutive expression of pMOL28-encoded nickel resistance in Alcaligenes eutrophus N9A.

    PubMed Central

    Siddiqui, R A; Schlegel, H G; Meyer, M

    1988-01-01

    The nickel and cobalt resistance plasmid pMOL28 was transferred by conjugation from its natural host Alcaligenes eutrophus CH34 to the susceptible A. eutrophus N9A. Strain N9A and its pMOL28-containing transconjugant M220 were studied in detail. At a concentration of 3.0 mM NiCl2, the wild-type N9A did not grow, while M220 started to grow at its maximum exponential growth rate after a lag of 12 to 24 h. When grown in the presence of subinhibitory concentrations (0.5 mM) of nickel salt, M220 grew actively at 3 mM NiCl2 without a lag, indicating that nickel resistance is an inducible property. Expression of nickel resistance required active growth in the presence of nickel salts at a concentration higher than 0.05 mM. Two mutants of M220 were isolated which expressed nickel resistance constitutively. When the plasmids, pMOL28.1 and pMOL28.2, carried by the mutants were transferred to strains H16 and CH34, the transconjugants expressed constitutive nickel resistance. This indicates that the mutation is plasmid located. Both mutants expressed constitutive resistance to nickel and cobalt. Physiological studies revealed the following differences between strain N9A and its pMOL28.1-harboring mutant derivatives. (i) The uptake of 63NiCl2 occurred more rapidly in the susceptible strain and reached a 30- to 60-fold-higher amount that in the pMOL28.1-harboring mutant; (ii) in intact cells of the susceptible strain N9A, the cytoplasmic hydrogenase was inhibited by 1 to 5 nM NiCl2, whereas 10 mM Ni2+ was needed to inhibit the hydrogenase of mutant cells; (iii) the minimal concentration of nickel chloride for the derepressed synthesis of cytoplasmic hydrogenase was lower in strain N9A (1 to 3 microM) than in the constitutive mutant (8 to 10 microM). PMID:3410828

  8. xPyder: a PyMOL plugin to analyze coupled residues and their networks in protein structures.

    PubMed

    Pasi, Marco; Tiberti, Matteo; Arrigoni, Alberto; Papaleo, Elena

    2012-07-23

    A versatile method to directly identify and analyze short- or long-range coupled or communicating residues in a protein conformational ensemble is of extreme relevance to achieve a complete understanding of protein dynamics and structural communication routes. Here, we present xPyder, an interface between one of the most employed molecular graphics systems, PyMOL, and the analysis of dynamical cross-correlation matrices (DCCM). The approach can also be extended, in principle, to matrices including other indexes of communication propensity or intensity between protein residues, as well as the persistence of intra- or intermolecular interactions, such as those underlying protein dynamics. The xPyder plugin for PyMOL 1.4 and 1.5 is offered as Open Source software via the GPL v2 license, and it can be found, along with the installation package, the user guide, and examples, at http://linux.btbs.unimib.it/xpyder/.

  9. Microstructure and mechanical properties of hot isostatically pressed zirconia (2 mol% yttria)-reinforced tungsten disilicide composites

    SciTech Connect

    Yamaguchi, Kotaro; Yoshinaka, Masaru; Hirota, Ken; Yamaguchi, Osamu

    1995-08-01

    Dense sintered composites of ZrO{sub 2} (2 mol% Y{sub 2}O{sub 3}) and WSi{sub 2} have been fabricated by hot isostatic pressing for 2 h at 1500 C under 196 MPa. They contain a small amount of W{sub 5}Si{sub 3}; during sintering, WSi{sub 2} decomposes into W{sub 5}Si{sub 3} and amorphous Si. The ZrO{sub 2} Particles in the composites consists of only t-ZrO{sub 2}. Microstructures and mechanical properties are examined, in connection with ZrO{sub 2} content. The fracture toughness and bending strength of the composite with 40 mol% ZrO{sub 2} addition are 7.1 MPa{center_dot}m{sup 1/2} and 1,011 MPa, respectively.

  10. PyMod: sequence similarity searches, multiple sequence-structure alignments, and homology modeling within PyMOL

    PubMed Central

    2012-01-01

    Background In recent years, an exponential growing number of tools for protein sequence analysis, editing and modeling tasks have been put at the disposal of the scientific community. Despite the vast majority of these tools have been released as open source software, their deep learning curves often discourages even the most experienced users. Results A simple and intuitive interface, PyMod, between the popular molecular graphics system PyMOL and several other tools (i.e., [PSI-]BLAST, ClustalW, MUSCLE, CEalign and MODELLER) has been developed, to show how the integration of the individual steps required for homology modeling and sequence/structure analysis within the PyMOL framework can hugely simplify these tasks. Sequence similarity searches, multiple sequence and structural alignments generation and editing, and even the possibility to merge sequence and structure alignments have been implemented in PyMod, with the aim of creating a simple, yet powerful tool for sequence and structure analysis and building of homology models. Conclusions PyMod represents a new tool for the analysis and the manipulation of protein sequences and structures. The ease of use, integration with many sequence retrieving and alignment tools and PyMOL, one of the most used molecular visualization system, are the key features of this tool. Source code, installation instructions, video tutorials and a user's guide are freely available at the URL http://schubert.bio.uniroma1.it/pymod/index.html PMID:22536966

  11. Preparation of TiO2 Nanocrystallite Powders Coated with 9 mol% ZnO for Cosmetic Applications in Sunscreens

    PubMed Central

    Ko, Horng-Huey; Chen, Hui-Ting; Yen, Feng-Ling; Lu, Wan-Chen; Kuo, Chih-Wei; Wang, Moo-Chin

    2012-01-01

    The preparation of TiO2 nanocrystallite powders coated with and without 9 mol% ZnO has been studied for cosmetic applications in sunscreens by a co-precipitation process using TiCl4 and Zn(NO3)2·6H2O as starting materials. XRD results show that the phases of anatase TiO2 and rutile TiO2 coexist for precursor powders without added ZnO (T-0Z) and calcined at 523 to 973 K for 2 h. When the T-0Z precursor powders are calcined at 1273 K for 2 h, only the rutile TiO2 appears. In addition, when the TiO2 precursor powders contain 9 mol% ZnO (T-9Z) are calcined at 873 to 973 K for 2 h, the crystallized samples are composed of the major phase of rutile TiO2 and the minor phases of anatase TiO2 and Zn2Ti3O8. The analyses of UV/VIS/NIR spectra reveal that the absorption of the T-9Z precursor powders after being calcined has a red-shift effect in the UV range with increasing calcination temperature. Therefore, the TiO2 nanocrystallite powders coated with 9 mol% ZnO can be used as the attenuate agent in the UV-A region for cosmetic applications in sunscreens. PMID:22408415

  12. Observational data and orbits of the asteroids discovered at the Molėtai Observatory in 2005-2007

    NASA Astrophysics Data System (ADS)

    Černis, K.; Wlodarczyk, I.; Zdanavičius, J.

    The paper presents statistics of the asteroids observed and discovered at the Molėtai Observatory, Lithuania, in 2005-2007 within the project for astrometric observations of the near-Earth objects (NEOs), the main belt asteroids and comets. CCD observations of asteroids were obtained with the 35/51 cm Maksutov-type meniscus telescope and the 1.65 m Ritchey-Chretien reflector. In the Minor Planet Circulars and the Minor Planet Electronic Circulars (2005-2007) we published 17 003 astrometric positions of 2980 asteroids. Among them 112 were new normal asteroids and one NEO (2006 SF77) discovered at Molėtai; a few NEOs were found by our team independently. For the asteroids discovered at Molėtai their precise orbits were calculated. Because of short observational arc, a few asteroids have low-precision orbits and some asteroids have been lost. For three of them with low-precision orbital elements (NEO 2006 SF77 and two Mars crossers - 2006 SN368 and 2007 VM315), we present their ephemerides for 2016-2018.

  13. Preparation of TiO₂ nanocrystallite powders coated with 9 mol% ZnO for cosmetic applications in sunscreens.

    PubMed

    Ko, Horng-Huey; Chen, Hui-Ting; Yen, Feng-Ling; Lu, Wan-Chen; Kuo, Chih-Wei; Wang, Moo-Chin

    2012-01-01

    The preparation of TiO(2) nanocrystallite powders coated with and without 9 mol% ZnO has been studied for cosmetic applications in sunscreens by a co-precipitation process using TiCl(4) and Zn(NO(3))(2)·6H(2)O as starting materials. XRD results show that the phases of anatase TiO(2) and rutile TiO(2) coexist for precursor powders without added ZnO (T-0Z) and calcined at 523 to 973 K for 2 h. When the T-0Z precursor powders are calcined at 1273 K for 2 h, only the rutile TiO(2) appears. In addition, when the TiO(2) precursor powders contain 9 mol% ZnO (T-9Z) are calcined at 873 to 973 K for 2 h, the crystallized samples are composed of the major phase of rutile TiO(2) and the minor phases of anatase TiO(2) and Zn(2)Ti(3)O(8). The analyses of UV/VIS/NIR spectra reveal that the absorption of the T-9Z precursor powders after being calcined has a red-shift effect in the UV range with increasing calcination temperature. Therefore, the TiO(2) nanocrystallite powders coated with 9 mol% ZnO can be used as the attenuate agent in the UV-A region for cosmetic applications in sunscreens.

  14. Efectos de la irradiación iónica en hielos de moléculas carbonadas

    NASA Astrophysics Data System (ADS)

    Satorre, M. A.

    En Astrofísica podemos encontrar numerosos contextos en los cuales se observan moléculas en estado sólido que, en condiciones estándar de presión y temperatura, se encontrarían como gases o líquidos. Dichas moléculas se denominan hielos y han sido observadas en nubes densas del medio interestelar, en envolturas circumestelares, en satélites del Sistema Solar, en cometas, etc. Los hielos pueden ser alterados en su composición química debido a diversos factores como por ejemplo variaciones de temperatura o aportes energéticos por parte de la irradiación, ya sea tanto de fotones ultravioleta como de iones. Dependiendo del escenario astrofísico que analicemos, unos factores cobran más importancia que otros. Los experimentos de laboratorio muestran el efecto que produce sobre la composición de los hielos la irradiación iónica, en particular sobre los que contenían alguna molécula con átomos de carbono. Dicha composición se analiza con espectroscopía IR en el rango de 2 a ˜ 25μ m. La aplicabilidad de los resultados de los experimentos es distinta dependiendo de la composición química inicial de los hielos, del tipo de ion utilizado y de la dosis total de irradiación. Existen efectos generales de la irradiación sobre la materia en los experimentos de relevancia astrofísica como son: - la formación de nuevas moléculas, que pueden incluir o no el ion incidente; - la progresiva pérdida de hidrógeno (carbonización) cuando irradiamos muestras que originalmente contienen una determinada relación carbono/hidrógeno; - la variación de la temperatura de sublimación que presentan algunos hielos. Esto puede suceder tanto en hielos que estaban presentes antes de la irradiación como en hielos formados por ésta. Se presentará el papel del ion en la formación de nuevas moléculas a partir de las que originalmente se encontraban en el hielo. Al penetrar en él, el ion provoca distintos procesos como rotura de enlaces y excitaciones electr

  15. WebMolCS: A Web-Based Interface for Visualizing Molecules in Three-Dimensional Chemical Spaces.

    PubMed

    Awale, Mahendra; Probst, Daniel; Reymond, Jean-Louis

    2017-03-30

    The concept of chemical space provides a convenient framework to analyze large collections of molecules by placing them in property spaces where distances represent similarities. Here we report webMolCS, a new type of web-based interface visualizing up to 5000 user-defined molecules in six different three-dimensional (3D) chemical spaces obtained by principal component analysis or similarity mapping of multidimensional property spaces describing composition (MQN: 42D molecular quantum numbers, SMIfp: 34D SMILES fingerprint), shapes and pharmacophores (APfp: 20D atom pair fingerprint, Xfp: 55D category extended atom pair fingerprint), and substructures (Sfp: 1024D binary substructure fingerprint, ECfp4:1024D extended connectivity fingerprint). Each molecule is shown as a sphere, and its structure appears on mouse over. The sphere is color-coded by similarity to the first compound in the list, by the list rank, or by a user-defined value, which reveals the relationship between any property encoded by these values and structural similarities. WebMolCS is freely available at www.gdb.unibe.ch .

  16. Observational data and orbits of the asteroids discovered at the Molėtai observatory in 2008-2009

    NASA Astrophysics Data System (ADS)

    Černis, K.; Wlodarczyk, I.; Zdanavičius, J.

    We present the statistics of the asteroids observed and discovered at the Molėtai Observatory, Lithuania, in 2008-2009 within the project for astrometric observations of the near-Earth objects (NEOs), the main belt asteroids and comets. CCD observations of the asteroids were obtained with the 35/51-cm Maksutov-type meniscus telescope. In the Minor Planet Circulars and the Minor Planet Electronic Circulars (2008-2009), 11 900 astrometric positions of 2522 asteroids were published. Among them 95 were new asteroids, including four belonging to the Trojan group: (352655) 2008QX28, 2008 SE8, (353194) 2009 SM100 and (264068) 2009 SQ148. For the asteroids discovered at Molėtai their precise orbits are calculated. Because of short observational arc, a few asteroids have low-precision orbits and some asteroids are considered lost. For the three Main Belt asteroids with low-precision orbital elements, 2008 QP32, 2008 SD8 and 2008 SG150, we present their ephemerides for 2017. They can be brighter than 20 mag.

  17. 3d-modelling workflows for trans-nationally shared geological models - first approaches from the project GeoMol

    NASA Astrophysics Data System (ADS)

    Rupf, Isabel

    2013-04-01

    To meet the EU's ambitious targets for carbon emission reduction, renewable energy production has to be strongly upgraded and made more efficient for grid energy storage. Alpine Foreland Basins feature a unique geological inventory which can contribute substantially to tackle these challenges. They offer a geothermal potential and storage capacity for compressed air, as well as space for underground storage of CO2. Exploiting these natural subsurface resources will strongly compete with existing oil and gas claims and groundwater issues. The project GeoMol will provide consistent 3-dimensional subsurface information about the Alpine Foreland Basins based on a holistic and transnational approach. Core of the project GeoMol is a geological framework model for the entire Northern Molasse Basin, complemented by five detailed models in pilot areas, also in the Po Basin, which are dedicated to specific questions of subsurface use. The models will consist of up to 13 litho-stratigraphic horizons ranging from the Cenozoic basin fill down to Mesozoic and late Paleozoic sedimentary rocks and the crystalline basement. More than 5000 wells and 28 000 km seismic lines serve as input data sets for the geological subsurface model. The data have multiple sources and various acquisition dates, and their interpretations have gone through several paradigm changes. Therefore, it is necessary to standardize the data with regards to technical parameters and content prior to further analysis (cf. Capar et al. 2013, EGU2013-5349). Each partner will build its own geological subsurface model with different software solutions for seismic interpretation and 3d-modelling. Therefore, 3d-modelling follows different software- and partner-specific workflows. One of the main challenges of the project is to ensure a seamlessly fitting framework model. It is necessary to define several milestones for cross border checks during the whole modelling process. Hence, the main input data set of the

  18. Purification of the 22000- and 20000-mol.wt. forms of human somatotropin and characterization of their binding to liver and mammary binding sites.

    PubMed Central

    Closset, J; Smal, J; Gomez, F; Hennen, G

    1983-01-01

    Quantitative data concerning the binding of 22000-mol.wt. human somatotropin and its 20000-mol.wt. variant are described using pregnant-rabbit liver and mammary-gland receptors. The purification and the complete chemical characterization of both human somatotropin and its 20000-mol.wt. variant is also presented. Contamination of the 20000-mol.wt.-variant preparation by 22000-mol.wt. hormone was found to be 0.5% by weight as measured in radioimmunoassay using monoclonal antibody. Labelling of human somatotropin and its 20000-mol.wt. variant using the Iodogen method is described as well as the characterization of the binding to pregnant-rabbit liver and mammary-gland receptor preparations. The maximum binding capacity of the 125I-labelled human somatotropin was between 50 and 60% to liver particulate receptor, whereas that of the 20000-mol.wt. variant was 30%. The specificity of binding of both forms to rabbit hepatic and mammary-gland receptor was found to be similar for both proteins in the same system. The affinity constants and capacity were respectively 0.7 X 10(10)M-1 and 815 fmol/mg of protein for human somatotropin and 0.6 X 10(10)M-1 and 1.250 fmol/mg of protein for the 20000-mol.wt. variant. These data suggest that both proteins behave as partial agonists to the receptors studied. PMID:6312965

  19. Determination of absorptivity and formation constant of a chalcone association complex.

    PubMed

    Blanco, S E; Ferretti, F H

    1998-04-01

    A UV spectrometric method was developed to determine the molar absorptivity (epsilon(C)) and formation constant (K(c)) of the association complex of unsubstituted chalcone in cyclohexane, in the concentration range from 4.00.10(-4) to 2.00.10(-2) mol dm(-3). The thermodynamic and spectroscopic magnitudes such as K(c) and epsilon(C) contribute to the understanding of the physicochemical behavior of several alpha,beta-unsaturated carbonylic compounds, of low solubility in water, as it is the case of numerous flavonoids of chemical and biological importance. The studied association complex, formed by two chalcone molecules, is characterized by the constants epsilon(C) (300.8 nm)=4.98.10(4) dm(3) mol(-1) cm(-1) and K(c)=5.58.10(3). The method proposed is convenient for the study of solute-solute molecular associations particularly those due to dipole-dipole interactions.

  20. Low temperature and magnetic field behaviour of the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy

    SciTech Connect

    Jacobs, B. S. Sheppard, C. J.; Prinsloo, A. R. E.; Lodya, L.

    2014-05-07

    Measurements of the temperature (T) dependence of the magnetic susceptibility (χ) and electrical resistance (R) on an antiferromagnetic (AFM) (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy are reported in order to probe the existence of quantum critical behaviour (QCB) utilizing static magnetic fields (H) as a tuning parameter. The results indicate that an increase in H suppresses T{sub N} in such a way that it varies exponentially with increasing H. R(T) measurements show evidence of possible superconducting (SC) behaviour below 1 K at H = 0 T. These results therefore indicate the coexistence of the AFM and SC phases in the (Cr{sub 84}Re{sub 16}){sub 89.6}V{sub 10.4} alloy.

  1. Excitação e fotoabsorção de moléculas interestelares no ultra violeta

    NASA Astrophysics Data System (ADS)

    Rodrigues, A. M. F.; Boechat-Roberty, H. M.; Souza, G. B.; Turci, C. C.

    2003-08-01

    O estudo dos processos de excitação, fotoabsorção e ionização molecular nas nuvens interestelar, permite a análise dos processos químicos, como a formação e destruição de moléculas, até mesmo daquelas que dão origem à vida. Acredita-se que as moléculas como CS2, NH3, CO2 e N2O estão presentes nas nuvens onde são formadas as estrelas e seus sistemas planetários. Estas moléculas são congeladas na superfície de objetos densos, como aqueles encontrados na Nuvem de Oort do nosso Sistema Solar. Quando esses objetos (cometas) desprendem-se dessa região, aproximam-se do Sol, sofrem a interação da radição Ultra Violeta (UV), passam à fase gasosa e são bombardeados por íons e elétrons presentes nos ventos solares. Obtivemos os espectros de fotoabsorção do CS2, NH3 e N2O na faixa do UV, convertendo espectros de Perda de Energia de Elétrons, medidos no menor ângulo de espalhamento e na energia de impacto de 1000 eV. Destes espectros determinamos os valores de força de oscilador (f) e de seção de choque absolutas na faixa de 500 a 2000 Å. Para tal, estudamos e comparamos dois diferentes métodos de conversão. Neste trabalho também geramos muitos dados moleculares como, valores absolutos de seção de choque elástica em função do ângulo de espalhamento e a distribuição de força do oscilador generalizada (df/dE) em função da energia de excitação para diversos ângulos de espalhamento. Comparando nossos espectros de fotoabsorção com o espectro da atmosfera de Júpiter, obtido pelo Telescópio Espacial Hubble, logo após o impacto do cometa Shoemaker-Levy 9, confirmamos a presença do CS2 e da amônia.

  2. Characterization of the inducible nickel and cobalt resistance determinant cnr from pMOL28 of Alcaligenes eutrophus CH34.

    PubMed Central

    Liesegang, H; Lemke, K; Siddiqui, R A; Schlegel, H G

    1993-01-01

    From pMOL28, one of the two heavy metal resistance plasmids of Alcaligenes eutrophus strain CH34, we cloned an EcoRI-PstI fragment into plasmid pVDZ'2. This hybrid plasmid conferred inducible nickel and cobalt resistance (cnr) in two distinct plasmid-free A. eutrophus hosts, strains AE104 and H16. Resistances were not expressed in Escherichia coli. The nucleotide sequence of the 8.5-kb EcoRI-PstI fragment (8,528 bp) revealed seven open reading frames; two of these, cnrB and cnrA, were assigned with respect to size and location to polypeptides expressed in E. coli under the control of the bacteriophage T7 promoter. The genes cnrC (44 kDa), cnrB (40 kDa), and cnrA (115.5 kDa) are probably structural genes; the gene loci cnrH (11.6 kDa), cnrR (tentatively assigned to open reading frame 1 [ORF]; 15.5 kDa), and cnrY (tentatively assigned to ORF0ab; ORF0a, 11.0 kDa; ORF0b, 10.3 kDa) are probably involved in the regulation of expression. ORF0ab and ORF1 exhibit a codon usage that is not typical for A. eutrophus. The 8.5-kb EcoRI-PstI fragment was mapped by Tn5 transposon insertion mutagenesis. Among 72 insertion mutants, the majority were nickel sensitive. The mutations located upstream of cnrC resulted in various phenotypic changes: (i) each mutation in one of the gene loci cnrYRH caused constitutivity, (ii) a mutation in cnrH resulted in different expression of cobalt and nickel resistance in the hosts H16 and AE104, and (iii) mutations in cnrY resulted in two- to fivefold-increased nickel resistance in both hosts. These genes are considered to be involved in the regulation of cnr. Comparison of cnr of pMOL28 with czc of pMOL30, the other large plasmid of CH34, revealed that the structural genes are arranged in the same order and determine proteins of similar molecular weights. The largest protein CnrA shares 46% amino acid similarity with CzcA (the largest protein of the czc operon). The other putative gene products, CnrB and CnrC, share 28 and 30% similarity

  3. Radio frequency interference survey over the 1.0-10.4 GHz frequency range at the Goldstone-Venus Development Station

    NASA Technical Reports Server (NTRS)

    Gulkis, S.; Olsen, E. T.; Klein, M. J.; Jackson, E. B.

    1989-01-01

    The results of a low sensitivity Radio Frequency Interference (RFI) survey carried out at the Venus Station of the Goldstone Communications Complex are reported. The data cover the spectral range from 1 GHz to 10.4 GHz with a 10-kHz instantaneous bandwidth. Frequency and power levels were observed using a sweep-frequency spectrum analyzer connected to a 1-m diameter antenna pointed at zenith. The survey was conducted from February 16, 1987 through February 24, 1987.

  4. Bilateral key comparison CCM.P-K3.1 for absolute pressure measurements from 3 × 10-6 Pa to 9 × 10-4 Pa

    NASA Astrophysics Data System (ADS)

    Fedchak, J. A.; Bock, Th; Jousten, K.

    2014-01-01

    This report describes the bilateral key comparison CCM.P-K3.1 between the National Institute of Standards and Technology (NIST) and Physikalisch-Technische Bundesanstalt (PTB) for absolute pressure in the range from 3 × 10-6 Pa to 9 × 10-4 Pa. This comparison was a follow-up to the comparison CCM.P-K3. Two ionization gauges and two spinning rotor gauges (SRGs) were used as the transfer standards for the comparison. The SRGs were used to compare the standards at a pressure of 9 × 10-4 Pa and to normalize the ionization gauge readings. The two ionization gauges were used to compare the standards in the pressure range of from 3 × 10-6 Pa to 3 × 10-4 Pa. Both laboratories used dynamic expansion chambers as standards in the comparison. The two labs showed excellent agreement with each other and with the CCM.P-K3 key comparison reference value (KCRV) over the entire range. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  5. Détection et exaltation de la luminescence de molécules biologiques individuelles en solution

    NASA Astrophysics Data System (ADS)

    Etienne, E.; Lenne, P. F.; Rigneault, H.

    2002-06-01

    La Spectroscopie de Corrélation de Fluorescence (FCS) est une technique d'analyse statistique des fluctuations de luminescence produites par des molécules fluorescentes diffusant librement dans un volume de collection de quelque μm^3. Une limitation fondamentale de la technique provient de l'ouverture numérique limitée des systèmes optiques conventionnels qui ne collectent qu'une faible partie des photons émis. Nous présentons des résultats relatifs à l'augmentation du nombre de photons collectés en utilisant le concept du contrôle de l'émission spontanée par des structures photoniques de type miroir diélectrique.

  6. Temperature-Dependent Sellmeier Equation for Refractive Index of 1.0 mol % Mg-Doped Stoichiometric Lithium Tantalate

    NASA Astrophysics Data System (ADS)

    Lim, Hwan Hong; Kurimura, Sunao; Katagai, Toshio; Shoji, Ichiro

    2013-03-01

    Mg-doped stoichiometric lithium tantalate (SLT) is a promising material in high power generation, due to its high thermal conductivity. The accuracy of the temperature-dependent Sellmeier equation for Mg-doped SLT is important for designing high-power-frequency converters. We propose a temperature-dependent Sellmeier equation for the extraordinary refractive index of 1.0 mol % Mg-doped SLT. The equation is fitted with measured data in the first-order quasi-phase-matched (QPM) second harmonic generation (SHG) and optical parametric oscillation (OPO) with the fundamental and pump wavelengths being both 1.064 µm and previously published data [Jpn. J. Appl. Phys. 41 (2002) 465] of SLT. The equation allows us to predict accurate QPM periods in the range of 0.5-4 µm wavelength and in temperature range of 30-170 °C.

  7. Adhesive evaluation of thin films of LARC-TPI and LARC-TPI with 5 mol % ODA

    NASA Technical Reports Server (NTRS)

    Progar, D. J.

    1986-01-01

    A commercially available LARC-TPI film and an experimentally prepared film of LARC-TPI with 5 mol % of 4,4'-oxydianiline (ODA), designated as LARC-TPI/ODA in the report, supplied by Mitsui Toatsu Chemicals, Incorporated (MTCI), Japan, were evaluated as thermoplastic adhesive films for bonding Ti-6Al-4V. The LARC-TPI/ODA had been shown by MTCI to possess more flow than thermoplastic LARC-TPI and was, therefore, evaluated and compared to the LARC-TPI. Lap shear strength was used to evaluate the materials as adhesives. They were characterized after fracture by determining the glass transition temperature, Tg. The mode of failure was also reported. Thermal exposure at 204C for 500 and 1000 hrs and a 72-hour water-boil were conducted on lap shear specimens prepared with the two adhesive films. Lap shear tests were conducted at RT, 177C, 204C, and 232C before and after exposures.

  8. Final report on international key comparison APMP.QM-K41: 10 µmol/mol hydrogen sulfide in nitrogen

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Doo; Heo, Gwi-Suk; Lee, Sangil; Han, Qiao; Wu, Hai; Konopelko, Leonid A.; Kustikov, Yury A.; Malginov, Andrey V.; Gromova, Elena V.; Pankratov, Vladimir V.; Pavlov, Mikhai V.; Botha, Angelique

    2014-01-01

    This report presents the results of APMP.QM-K41, a key comparison. This comparison is designed to test the capabilities of the NMIs to measure and certify hydrogen sulfide at a nominal amount fraction of 10 µmol/mol in nitrogen. This comparison provides an opportunity to the NMIs in APMP to submit supporting evidence for CMC at the same level as CCQM-K41. The results from this comparison are linked with CCQM-K41. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. Final report on international comparison APMP.QM-S4: Carbon dioxide in nitrogen at 2000 µmol/mol

    NASA Astrophysics Data System (ADS)

    Doo Kim, Yong; Kim, Kwang Seob; Lee, Sangil; Hyub Oh, Sang; Lin, Tsai-Yin; Cheng, Jui-Hsiang; Huang, Chiung-Kun

    2014-01-01

    This report presents the results of APMP.QM-S4, a supplementary comparison. This comparison is designed to test the capabilities of the NMIs to measure and certify carbon dioxide at a nominal amount fraction of 2000 µmol/mol in nitrogen. The previous key comparisons regarding carbon dioxide, CCQM-K1.b and CCQM-K52, had been done at a lower range than that in this comparison. This comparison gives an opportunity to the NMIs to submit supporting evidence for CMC at a higher range. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  10. MLP Tools: a PyMOL plugin for using the molecular lipophilicity potential in computer-aided drug design

    NASA Astrophysics Data System (ADS)

    Oberhauser, Nils; Nurisso, Alessandra; Carrupt, Pierre-Alain

    2014-05-01

    The molecular lipophilicity potential (MLP) is a well-established method to calculate and visualize lipophilicity on molecules. We are here introducing a new computational tool named MLP Tools, written in the programming language Python, and conceived as a free plugin for the popular open source molecular viewer PyMOL. The plugin is divided into several sub-programs which allow the visualization of the MLP on molecular surfaces, as well as in three-dimensional space in order to analyze lipophilic properties of binding pockets. The sub-program Log MLP also implements the virtual log P which allows the prediction of the octanol/water partition coefficients on multiple three-dimensional conformations of the same molecule. An implementation on the recently introduced MLP GOLD procedure, improving the GOLD docking performance in hydrophobic pockets, is also part of the plugin. In this article, all functions of the MLP Tools will be described through a few chosen examples.

  11. VizieR Online Data Catalog: ExoMol line lists for AlO (Patrascu+, 2015)

    NASA Astrophysics Data System (ADS)

    Patrascu, A. T.; Yurchenko, S. N.; Tennyson, J.

    2015-03-01

    The data for each isotopologue are in two parts. The first, .states contains a list of rovibronic states. Each state is labelled with the total angular momentum, state degeneracy, total parity, vibrational quantum number, projection of the electronic, spin and total angular momenta. Each state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. A sample programme to generate synthetic spectra from the ExoMol format line lists can be obtained at www.exomol.com. (8 data files).

  12. Development of a NIST standard reference material containing thirty volatile organic compounds at 5 nmol/mol in nitrogen.

    PubMed

    Rhoderick, George C; Yen, James H

    2006-05-01

    Primary gravimetric gas cylinder standards containing 30 volatile organic compounds (VOCs) in nitrogen were prepared using a procedure previously developed to prepare gas mixture cylinder standards of VOCs at the 5 nmol/mol level. This set of primary standards was intercompared to existing gas cylinder standards, containing as many as 19 of the 30 volatile organics present in these new primaries, using gas chromatography with a hydrogen flame ionization detector coupled with cryogenic preconcentration. The linear regression analysis showed excellent agreement among the standards for each compound. Similar mixtures containing many of these compounds in treated aluminum gas cylinders have been evaluated over time and have shown stability for as much as 10 years. The development of these 30-component primary standards led to the preparation and certification of a reissue of Standard Reference Material (SRM) 1804 at the nominal amount-of-substance fraction of 5 nmol/mol for each analyte. A lot of 20 cylinders containing the mixture was prepared at NIST following previously demonstrated protocols for preparation of the cylinders. Each cylinder was analyzed against one cylinder from the lot, designated as the "lot standard," for each of the 30 compounds. As a result of the uncertainty analysis, the data showed that rather than declaring the lot homogeneous with a much higher uncertainty, each cylinder could be individually certified. The expanded uncertainty limits ranged from 1.5 to 10% for 28 of the 30 analytes, with two of the analytes having uncertainties as high as 19% in those SRM cylinders certified. Due to stability issues and some high uncertainties for a few analytes in 2 of the samples, 18 of the 20 candidate SRM samples were certified. These volatile organic gas mixtures represent the most complex gas SRMs developed at NIST.

  13. Cristallisation, syncristallisation, et alliages moléculaires entre le lorazépam et l'oxazépam

    NASA Astrophysics Data System (ADS)

    Mascherpa-Corral, D.; Mascherpa, G.; Chauvet, A.

    1993-04-01

    Le polymorphisme et pseudopolymorphisme du lorazépam et oxazépam ont été étudiés par analyse thermique, calorimétrie différentielle à balayage et diffraction de rayons X. Deux formes polymorphes du lorazépam et plusieurs mono et hemisolvates ont été isolés à partir de recristallisation dans divers soivants. Aucun polymorphisme ni solvate n'a été mis en évidence avec l'oxazépam. Les paramètres cristallographiques des phases isolées ont été déterminées. A 160 et 203°C, le lorazépam et l'oxazépam perdent respectivement une molécule d'eau pour donner après réarrangement la quinazolinecarboxaldéhyde correspondante. La syncristallisation des deux benzodiazépines dans le benzène conduit à des alliages moléculaires à miscibilité totale à l'état solide dans tout le domaine de concentration entre l'exazépam el la forme α du lorazépam, elle n'est que partielle avec la forme β. Thermal analysis, differential scanning calorimetry, and X-ray diffraction were carried out to study the polymorphism and pseudopolymorphism of lorazepam and oxazepam. Two polymorphic forms of lorazepam and several mono- or hemisolvates were obtained after recrystallization from various solvents. No polymorphic form or solvate has been found for oxazepam. The crystallographic parameters of these new phases were determined. Lorazepam and oxazepam can lose a molecule of water at 160 and 203°C, respectively, and rearrange to quinazolinecarboxaldehyde. Mixed crystals of the two benzodiazepines, after recrystallization from benzene, lead to molecular alloys with complete solid solubility between oxazepam and the α-form of lorazepam over the whole range of composition but only to partial solubility with the β-form of lorazepam.

  14. Laboratory and Sky Testing Results for the TIS H4RG-10 4k x 4k, 10 micron Visible CMOS-Hybrid Detector

    DTIC Science & Technology

    2007-01-01

    Laboratory and Sky Testing Results for the TIS H4RG -10 4k x 4k, 10 micron visible CMOS-Hybrid Detector Bryan N. Dorland∗a, Gregory S...Drive, Suite 200, Greenbelt, MD 20770 ABSTRACT We present both laboratory and telescope testing results describing the performance of the H4RG -10 CMOS...Hybrid detector. The H4RG -10 is the largest visible hybrid array currently in existence and shows great potential for use in future space missions

  15. Interaction of the 70,000-mol-wt amino-terminal fragment of fibronectin with the matrix-assembly receptor of fibroblasts

    PubMed Central

    1985-01-01

    Plasma fibronectin binds saturably and reversibly to substrate-attached fibroblasts and is subsequently incorporated into the extracellular matrix (McKeown-Longo, P.J., and D. F. Mosher, 1983, J. Cell Biol., 97:466-472). We examined whether fragments of fibronectin are processed in a similar way. The amino-terminal 70,000-mol-wt catheptic D fragment of fibronectin bound reversibly to cell surfaces with the same affinity as intact fibronectin but did not become incorporated into extracellular matrix. The 70,000-mol-wt fragment blocked binding of intact fibronectin to cell surfaces and incorporation of intact fibronectin into extracellular matrix. Binding of the 70,000-mol-wt fragment to cells was partially abolished by cleavage into 27,000-mol- wt heparin-binding and 40,000-mol-wt gelatin-binding fragments and more completely abolished by reduction and alkylation of disulfide bonds. Binding of the 70,000-mol-wt fragment to cells was not blocked by gelatin or heparin. When coated onto plastic, the 70,000-mol-wt fragment did not mediate attachment and spreading of suspended fibroblasts. Conversely, fibronectin fragments that had attachment and spreading activity did not block binding of exogenous fibronectin to substrate-attached cells. These results indicate that there is a cell binding site in the 70,000-mol-wt fragment that is distinct from the previously described cell attachment site and is required for assembly of exogenous fibronectin into extracellular matrix. PMID:3155749

  16. Crystal and mol-ecular structure of meso-2,6-di-bromo-hepta-nedioic acid (meso-2,6-di-bromo-pimelic acid).

    PubMed

    Dirda, Nathaniel D A; Zavalij, Peter Y; Kao, Joseph P Y

    2016-03-01

    The mol-ecular structure of the title compound, C7H10Br2O4, confirms the meso (2R,6S) configuration. In the crystal, mol-ecules are linked by pairs of O-H⋯O=C hydrogen bonds between their terminal carboxyl groups in an R 2 (2)(8) motif, forming extended chains that propagate parallel to the c axis. Adjacent chains are linked by C=O⋯Br halogen bonds.

  17. Mutations in the human SC4MOL gene encoding a methyl sterol oxidase cause psoriasiform dermatitis, microcephaly, and developmental delay

    PubMed Central

    He, Miao; Kratz, Lisa E.; Michel, Joshua J.; Vallejo, Abbe N.; Ferris, Laura; Kelley, Richard I.; Hoover, Jacqueline J.; Jukic, Drazen; Gibson, K. Michael; Wolfe, Lynne A.; Ramachandran, Dhanya; Zwick, Michael E.; Vockley, Jerry

    2011-01-01

    Defects in cholesterol synthesis result in a wide variety of symptoms, from neonatal lethality to the relatively mild dysmorphic features and developmental delay found in individuals with Smith-Lemli-Opitz syndrome. We report here the identification of mutations in sterol-C4-methyl oxidase–like gene (SC4MOL) as the cause of an autosomal recessive syndrome in a human patient with psoriasiform dermatitis, arthralgias, congenital cataracts, microcephaly, and developmental delay. This gene encodes a sterol-C4-methyl oxidase (SMO), which catalyzes demethylation of C4-methylsterols in the cholesterol synthesis pathway. C4-Methylsterols are meiosis-activating sterols (MASs). They exist at high concentrations in the testis and ovary and play roles in meiosis activation. In this study, we found that an accumulation of MASs in the patient led to cell overproliferation in both skin and blood. SMO deficiency also substantially altered immunocyte phenotype and in vitro function. MASs serve as ligands for liver X receptors α and β (LXRα and LXRβ), which are important in regulating not only lipid transport in the epidermis, but also innate and adaptive immunity. Deficiency of SMO represents a biochemical defect in the cholesterol synthesis pathway, the clinical spectrum of which remains to be defined. PMID:21285510

  18. Catechin-based procyanidins from Peumus boldus Mol. aqueous extract inhibit Helicobacter pylori urease and adherence to adenocarcinoma gastric cells.

    PubMed

    Pastene, Edgar; Parada, Víctor; Avello, Marcia; Ruiz, Antonieta; García, Apolinaria

    2014-11-01

    In this work, the anti-Helicobacter pylori effect of an aqueous extract from dried leaves of Peumus boldus Mol. (Monimiaceae) was evaluated. This extract displayed high inhibitory activity against H. pylori urease. Therefore, in order to clarify the type of substances responsible for such effect, a bioassay-guided fractionation strategy was carried out. The active compounds in the fractions were characterized through different chromatographic methods (RP-HPLC; HILIC-HPLC). The fraction named F5 (mDP = 7.8) from aqueous extract was the most active against H. pylori urease with an IC50  = 15.9 µg gallic acid equivalents (GAE)/mL. HPLC analysis evidenced that F5 was composed mainly by catechin-derived proanthocyanidins (LC-MS and phloroglucinolysis). The anti-adherent effect of boldo was assessed by co-culture of H. pylori and AGS cells. Both the aqueous extract and F5 showed an anti-adherent effect in a concentration-dependent manner. An 89.3% of inhibition was reached at 2.0 mg GAE/mL of boldo extract. In conjunction, our results suggest that boldo extract has a potent anti-urease activity and anti-adherent effect against H. pylori, properties directly linked with the presence of catechin-derived proanthocyanidins.

  19. CisMols Analyzer: identification of compositionally similar cis-element clusters in ortholog conserved regions of coordinately expressed genes

    PubMed Central

    Jegga, Anil G.; Gupta, Ashima; Gowrisankar, Sivakumar; Deshmukh, Mrunal A.; Connolly, Steven; Finley, Kevin; Aronow, Bruce J.

    2005-01-01

    Combinatorial interactions of sequence-specific trans-acting factors with localized genomic cis-element clusters are the principal mechanism for regulating tissue-specific and developmental gene expression. With the emergence of expanding numbers of genome-wide expression analyses, the identification of the cis-elements responsible for specific patterns of transcriptional regulation represents a critical area of investigation. Computational methods for the identification of functional cis-regulatory modules are difficult to devise, principally because of the short length and degenerate nature of individual cis-element binding sites and the inherent complexity that is generated by combinatorial interactions within cis-clusters. Filtering candidate cis-element clusters based on phylogenetic conservation is helpful for an individual ortholog gene pair, but combining data from cis-conservation and coordinate expression across multiple genes is a more difficult problem. To approach this, we have extended an ortholog gene-pair database with additional analytical architecture to allow for the analysis and identification of maximal numbers of compositionally similar and phylogenetically conserved cis-regulatory element clusters from a list of user-selected genes. The system has been successfully tested with a series of functionally related and microarray profile-based co-expressed ortholog pairs of promoters and genes using known regulatory regions as training sets and co-expressed genes in the olfactory and immunohematologic systems as test sets. CisMols Analyzer is accessible via a Web interface at . PMID:15980500

  20. Computer experiments of aqueous solutions. V. Monte Carlo calculation on the hydrophobic interaction in 5 mol % methanol solution

    NASA Astrophysics Data System (ADS)

    Okazaki, Susumu; Touhara, Hidekazu; Nakanishi, Koichiro

    1984-07-01

    Monte Carlo calculation has been carried out for 5 mol % aqueous solution of methanol at 298.15 K and experimental density with the Metropolis scheme in NTV ensemble. The total number of molecules is 216, of which 11 are methanol. The three kinds of pair potential function used are all based on SCF MO calculations, namely, water-water interactions with MCY (Matsuoka-Clementi-Yoshimine) potential, water-methanol, and methanol-methanol interactions with those proposed by Okazaki et al. and Jorgensen. Totally 5 800 000 configurations have been generated and final 4 200 000 configurations have been used to the calculation of thermodynamic quantities and various distribution functions. It is found that the mixing is slightly exothermic which can be ascribed to the promotion of water structure around methanol rather than the formation of hydrogen bonding between water and methanol. Evidence is given for the existence of hydrophobic interaction effect and the self-association of methanol with or without one water layer in between.

  1. Mediterranean savanna of Acacia caven (Mol) is still a sink of CO2 in spite of severe hydrological drought conditions

    NASA Astrophysics Data System (ADS)

    Bravo-Martínez, F.; Meza, F. J.

    2012-12-01

    An eddy covariance tower was set up to monitor net ecosystem exchange (NEE) on a mediterranean shrubland of Acacia caven (Mol) in October 2010. This ecosystem (commonly referred as "espinal") is one of the most abundant land covers of Chile's central valley (2.000.000 ha). The last two years (2010-2011) were characterized by the occurrence of a severe drought (rainfall deficit 56%) and a small increase in temperature evaluated using a climatic change index (Peterson, 2005). We also detected a strong reduction in vegetation index during this period (evaluated using MODIS imagery). The historical analysis of the enhanced vegetation index (EVI) and leaf area index (LAI) showed that water status of the acacia savanna were at a minimum during this period (record of 14 years of data). The annual balance of NEE of 2011 was -54gC m-2 y-1, which means that the espinal is a sink of atmospheric CO2 notwithstanding the many stressors on photosynthesis. Monthly analysis of NEE shows the strong dependence of ecosystem fluxes on phenological state. Maximum rates of assimilation are a consequence of grassland activity, whereas secondary picks during the year (late spring and early autumn) are attributed to the semideciduos leaf of A. caven. Climatic conditions during the study season, confirm the tremendous plasticity of Acacia caven and its role as a colonizer of degraded sclerophyll forest because it adaptation to water and thermal stress.

  2. Détermination assistée par ordinateur de la structure des molécules organiques

    NASA Astrophysics Data System (ADS)

    Nuzillard, J.-M.

    1998-02-01

    Nuclear Magnetic Resonance spectroscopy offers the unique possibility of accessing proximity relationships between atoms by means of chemical shift correlation experiments. Structure determination of small molecules has become thus much simpler. Computer programs can use directly correlation information for structure analysis. The use and operation mechanism of such a program, LSD (Logic for Structure Determination) are presented. The example compound is gibberellic acid, a natural product. La spectroscopie de Résonance Magnétique Nucléaire offre un moyen unique de déterminer des relations de proximité entre atomes par le biais des expériences de corrélation. L'analyse structurale de petites molécules organiques s'en trouve extrêmement facilitée. Des programmes informatiques peuvent utiliser directement les informations de corrélation pour déduire des structures. Le fonctionnement et l'usage d'un tel programme, LSD (Logic for Structure Determination), sont détaillés sur un exemple, l'acide gibberellique.

  3. Transferability of cucumber microsatellite markers used for phylogenetic analysis and population structure study in bottle gourd (Lagenaria siceraria (Mol.) Standl.).

    PubMed

    Bhawna; Abdin, M Z; Arya, L; Verma, M

    2015-02-01

    Improved breeding for developing fruit quality in bottle gourd (Lagenaria siceraria (Mol.) Standl.) necessitates knowledge regarding its genetic diversity. To achieve this, a set of 108 locus-specific SSR markers has been developed in bottle gourd by cross-species transferability from 995 mapped Cucumis sativus SSR markers. During screening, 280 primer pairs amplified in the bottle gourd germplasm, which were further evaluated in a diverse set of 42 lines, resulting in 19 polymorphic, 89 monomorphic, 15 with multiple bands, and the rest 157 showed no or very non-specific amplification. The 19 polymorphic primer pairs produced a total of 54 alleles. Gene diversity, Shannon's information index, and Nei's coefficient of differentiation were calculated suggesting a moderate genetic variation at the species level. A model-based population structure analysis divided these germplasm into two subpopulations. This marker set will be applicable for evaluating the genetic structure for association mapping, DNA fingerprinting, and mounting linkage maps and will be a practical tool set for further genetics. This study provides one of the first quantitative views of population genetic variation in bottle gourd.

  4. MolShaCS: a free and open source tool for ligand similarity identification based on Gaussian descriptors.

    PubMed

    Vaz de Lima, Luis Antônio C; Nascimento, Alessandro S

    2013-01-01

    Molecular similarity evaluation is an important step in most drug development strategies, since molecular similarity is usually related to functional similarity. Here, we developed a method based on the Gaussian description of molecular shape and charge distribution for molecular similarity identification. The method was evaluated using the Directory of Useful Decoys (DUD) and a retrospective test. Enrichment factors computed for DUD targets showed that the proposed method performs very well in recognizing molecules with similar physicochemical properties and dissimilar topologies, reaching an average AUC of 0.63 and enrichment factor of 10 at 0.5% of decoys. A retrospective test also showed that nine mineralocorticoid ligands were ranked among the top ten molecules in a search of a database of approved drugs for molecules similar to aldosterone. Altogether, these data show that the Gaussian-based description of molecular shape and charge distribution implemented in the program MolShaCS is an efficient method for molecular similarity identification. The program is publicly available at the address http://www.ifsc.usp.br/biotechmol.

  5. NRGsuite: a PyMOL plugin to perform docking simulations in real time using FlexAID

    PubMed Central

    Gaudreault, Francis; Morency, Louis-Philippe; Najmanovich, Rafael J.

    2015-01-01

    Ligand protein docking simulations play a fundamental role in understanding molecular recognition. Herein we introduce the NRGsuite, a PyMOL plugin that permits the detection of surface cavities in proteins, their refinements, calculation of volume and use, individually or jointly, as target binding-sites for docking simulations with FlexAID. The NRGsuite offers the users control over a large number of important parameters in docking simulations including the assignment of flexible side-chains and definition of geometric constraints. Furthermore, the NRGsuite permits the visualization of the docking simulation in real time. The NRGsuite give access to powerful docking simulations that can be used in structure-guided drug design as well as an educational tool. The NRGsuite is implemented in Python and C/C++ with an easy to use package installer. The NRGsuite is available for Windows, Linux and MacOS. Availability and implementation: http://bcb.med.usherbrooke.ca/flexaid. Contact: rafael.najmanovich@usherbroke.ca Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26249810

  6. Structural and property changes in poly (vinylidene fluoride trifluoroethylene) 70/30 mol % copolymer induced by proton irradiation

    NASA Astrophysics Data System (ADS)

    Lau, S. T.; Chan, H. L. W.; Choy, C. L.

    2005-02-01

    Poly(vinylidene fluoride trifluoroethylene) 70/30 mol % copolymer has been irradiated with 3 MeV protons at doses ranging from 43 to 200 Mrad. The effects of irradiation on the polarization hysteresis, dielectric properties, lattice spacing, phase transition behavior and electric-field-induced strain have been studied. The irradiated copolymer exhibits the characteristic behavior of a relaxor ferroelectric, including frequency dispersion of the dielectric constant, which follows the Vogel Fulcher rule. These results indicate that the proton irradiation breaks up the coherent polarization domains in the copolymer into nano-sized regions, thereby converting the copolymer to a relaxor ferroelectric. X-ray diffraction measurements show that the nano-sized regions are in the non-polar phase. Since the lattice spacing of the non-polar phase is substantially different from that of the polar phase, the local phase transformation between these two phases induced by an external electric field gives rise to a large lattice strain and hence a giant electrostrictive response.

  7. MOL-D: A Collisional Database and Web Service within the Virtual Atomic and Molecular Data Center

    NASA Astrophysics Data System (ADS)

    Vujčič, V.; Jevremović, D.; Mihajlov, A. A.; Ignjatović, Lj. M.; Srećković, V. A.; Dimitrijević, M. S.; Malović, M.

    2015-12-01

    MOL-D database is a collection of cross-sections and rate coefficients for specific collisional processes and a web service within the Serbian Virtual Observatory (SerVO) and the Virtual Atomic and Molecular Data Center (VAMDC). This database contains photo-dissociation cross-sections for the individual ro-vibrational states of the diatomic molecular ions and rate coefficients for the atom-Rydberg atom chemi-ionization and inverse electron-ion-atom chemi-recombination processes. At the moment it contains data for photodissociation cross-sections of hydrogen H2+ and helium He2+ molecular ions and the corresponding averaged thermal photodissociation cross-sections. The ro-vibrational energy states and the corresponding dipole matrix elements are provided as well. Hydrogen and helium molecular ion data are important for calculation of solar and stellar atmosphere models and for radiative transport, as well as for kinetics of other astrophysical and laboratory plasma (i.e. early Universe).

  8. Prediction of HIV-1 protease inhibitor resistance by Molecular Modeling Protocols (MMPs) using GenMol software.

    PubMed

    Pèpe, G; Courcambeck, J; Perbost, R; Jouanna, P; Halfon, P

    2008-11-01

    This paper investigates the contribution of Molecular Modeling to (i) predict and (ii) understand more fundamentally HIV drug resistance. Based on a new automated GenMol module, these goals are approached by Molecular Modeling Protocols (MMPs), respectively, (i) the Molecular Modeling Phenotype Protocol (MMPP) and (ii) the Molecular Modeling Phenotype-Genotype Protocol (MMGPP). Section 2 recalls clinical practice with a reference case study and Section 3 presents atomistic simulation tools. Section 4 is the heart of the paper. In Section 4.1, MMPP drug resistance prediction is based on correlations between fold resistances versus binding energies on 2959 HIV-1 complexes with 6 protease inhibitors. Based on a drug sensitivity twofold criterion, modeling prediction is able to replace long and costly phenotype tests. In Section 4.2, MMGPP enlightens drug resistance by investigating steric and energetic residues/inhibitor interaction. Section 5 gives a synthesis on modeling contribution to drug resistance prediction. In conclusion, the most promising trend consists of MMP automats that are able to suggest a real time diagnosis taking into account the history of each patient, to enrich databases and to develop therapy strategy and new drugs.

  9. Y{sub 2}O{sub 3}:Eu{sup 3+} (5 mol%) with Ag nanoparticles prepared by citrate precursor

    SciTech Connect

    Ferrari, J.L.; Cebim, M.A.; Pires, A.M.; Couto dos Santos, M.A.

    2010-09-15

    Y{sub 2}O{sub 3}:Eu{sup 3+} (5 mol% Eu{sup 3+}) and Y{sub 2}O{sub 3}:Eu{sup 3+} (5 mol% Eu{sup 3+}) containing 1 mol% of Ag nanoparticles were prepared by heat treatment of a viscous resin obtained via citrate precursor. TEM and EDS analyses showed that Y{sub 2}O{sub 3}:Eu{sup 3+} (5 mol% Eu{sup 3+}) is formed by nanoparticles with an average size of 12 nm, which increases to 30 nm when Ag is present because the effect of metal induced crystallization occurs. Ag nanoparticles with a size of 9 nm dispersed in Y{sub 2}O{sub 3}:Eu{sup 3+} (5 mol% Eu{sup 3+}) were obtained and the surface plasmon effect on Ag nanoparticles was observed. The emission around 612 nm assigned to the Eu{sup 3+} ({sup 5}D{sub 0{yields}}{sup 7}F{sub 2}) transition enhanced when the Ag nanoparticles were present in the Y{sub 2}O{sub 3}:Eu{sup 3+} luminescent material. - Graphical abstract: The presence of Ag nanoparticles together Y{sub 2}O{sub 3}:Eu{sup 3+} 5 mol% phosphor showed to affect directly the optical and crystallinity of the material. Luminescence spectra show directly the effect observed.

  10. Buffer Standards for pH Measurement of N-(2-Hydroxyethyl)piperazine-N'-2-ethanesulfonic Acid (HEPES) for I = 0.16 mol.kg from 5 to 55 degrees C.

    PubMed

    Roy, Rabindra N; Roy, Lakshmi N; Ashkenazi, Shahaf; Wollen, Joshua T; Dunseth, Craig D; Fuge, Michael S; Durden, Jared L; Roy, Chandra N; Hughes, Hannah M; Morris, Brett T; Cline, Kevin L

    2009-04-01

    The values of the second dissociation constant, pK(2) of N-(2-hydroxyethyl) piperazine-N'-2-ethanesulfonic acid (HEPES) have been reported at 12 temperatures over the temperature range 5 to 55 degrees C, including 37 degrees C. This paper reports the results for the pa(H) of eight isotonic saline buffer solutions with an I = 0.16 mol*kg(-1) including compositions: (a) HEPES (0.01 mol*kg(-1)) + NaHEPES (0.01 mol*kg(-1)) + NaCl (0.15 mol*kg(-1)); (b) HEPES (0.02 mol*kg(-1)) + NaHEPES (0.02 mol*kg(-1)) + NaCl (0.14 mol*kg(-1)); (c) HEPES (0.03 mol*kg(-1)) + NaHEPES (0.03 mol*kg(-1)) + NaCl (0.13 mol*kg(-1)); (d) HEPES (0.04 mol*kg(-1)) + NaHEPES (0.04 mol*kg(-1)) + NaCl (0.12 mol*kg(-1)); (e) HEPES (0.05 mol*kg(-1)) + NaHEPES (0.05 mol*kg(-1)) + NaCl (0.11 mol*kg(-1)); (f) HEPES (0.06 mol*kg(-1)) + NaHEPES (0.06 mol*kg(-1)) + NaCl (0.10 mol*kg(-1)); (g) HEPES (0.07 mol*kg(-1)) + NaHEPES (0.07 mol*kg(-1)) + NaCl (0.09 mol*kg(-1)); and (h) HEPES (0.08 mol*kg(-1)) + NaHEPES (0.08 mol*kg(-1)) + NaCl (0.08 mol*kg(-1)). Conventional pa(H) values, for all eight buffer solutions from 5 to 55 degrees C have been calculated. The operational pH values with liquid junction corrections, at 25 and 37 degrees C have been determined based on the NBS/NIST standard between the physiological phosphate standard and four buffer solutions. These are recommended as pH standards for physiological fluids in the range of pH 7.3 to 7.5 at I = 0.16 mol*kg(-1).

  11. MASSIVE STAR FORMATION, OUTFLOWS, AND ANOMALOUS H{sub 2} EMISSION IN Mol 121 (IRAS 20188+3928)

    SciTech Connect

    Wolf-Chase, Grace; Arvidsson, Kim; Smutko, Michael; Sherman, Reid

    2013-01-10

    We have discovered 12 new molecular hydrogen emission-line objects (MHOs) in the vicinity of the candidate massive young stellar object Mol 121, in addition to five that were previously known. H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m flux ratios indicate another region dominated by fluorescence from a photodissociation region, and one region that displays an anomalously low H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m flux ratio (<1) and coincides with a previously reported deeply embedded source (DES). Continuum observations at 3 mm reveal five dense cores; the brightest core is coincident with the DES. The next brightest cores are both associated with centimeter continuum emission. One of these is coincident with the IRAS source; the other lies at the centroid of a compact outflow defined by bipolar MHOs. The brighter of these bipolar MHOs exhibits [Fe II] emission and both MHOs are associated with CH{sub 3}OH maser emission observed at 95 GHz and 44 GHz. Masses and column densities of all five cores are consistent with theoretical predictions for massive star formation. Although it is impossible to associate all MHOs with driving sources in this region, it is evident that there are several outflows along different position angles, and some unambiguous associations can be made. We discuss implications of observed H{sub 2} 2.12 {mu}m/H{sub 2} 2.25 {mu}m and [Fe II] 1.64 {mu}m/H{sub 2} 2.12 {mu}m flux ratios and compare the estimated total H{sub 2} luminosity with the bolometric luminosity of the region. We conclude that the outflows are driven by massive young stellar objects embedded in cores that are likely to be in different evolutionary stages.

  12. ExoMol: Large-scale production of line lists for molecules important for modelling of planetary atmospheres

    NASA Astrophysics Data System (ADS)

    Yurchenko, S.; Tennyson, J.

    2013-09-01

    The spectral characterization of astrophysical objects cool enough to form polyatomic molecules (the atmospheres of planets, brown dwarfs, planetary discs etc.) requires a huge amount of fundamental molecular data. With a few exceptions the existing molecular line lists are not sufficiently accurate and complete. The aim of ExoMol [1] is to generate comprehensive line lists for all molecules likely to be observable in exoplanet atmospheres in the foreseeable future (see www.exomol.com for more details). We identified the following 40 species that are important sources of opacity in (exo)planets and brown dwarfs and where there is currently a lack of fundamental data on wavelength and temperature-dependent absorption: • Diatomics: AlO, AlH, BeH, CaH, C2, CrH, FeH, HF, HCl, KCl, MgH, MgO, NaH, NaCl, NiH, O2,SiO, SiH, S2, SH, TiH, TiO, VO, YO • Triatomics: C3, H2S, SO2 • Tetratomics: H2CO, H2CS, HCCH, HOOH, PH3,SO3 • Pentatomics: CH4, HNO3 • Larger molecules: C2H4, C2H6, C3H8, P2H2, P2H4 The production of comprehensive and very large rotation-vibration and rotation-vibration-electronic line lists requires a mixture of first principles quantum mechanical methods and empirical tuning based on laboratory spectroscopic data and makes extensive use of state-of-the-art computing. These and other aspects of molecular line lists, their production and astrophysical applications will be discussed. The contribution will make specific reference to molecules for which line lists have recently been completed or are nearing completion: phosphine, hydrogen sulphide, hydrogen peroxide, methane, formaldehyde, nitric acid as well as to a number of diatomic molecules of astrophysical importance, see Fig. 1.

  13. Capteur de CO{2} à fibres optiques par absorption moléculaire à 4,3 μm

    NASA Astrophysics Data System (ADS)

    Bendamardji, S.; Alayli, Y.; Huard, S.

    1996-04-01

    This paper describes a remote optical fibre sensor for the carbon dioxide detection by molecular absorption in the near infrared (4.3 μm) corresponding to fundamental mode ν3. To overcome the problem of the strong attenuation signal of optical fibre in the near infrared, we have used the opto-suppling technique which changes the working wavelength from 4.3 μm to 860 nm and permits the use of standard optical fibre 50/125. The simulation of absorption has been obtained by original modelisation of the absorption spectrum and the establishment of the calibration curves takes to the sensor to detect a partial pressures greater than 100 μbar with a minimal error margin of 100 μbar, which is acceptable considering the future use of the device. The sensor has been designed to monitor the CO{2} rate in enriched greenhouses. Cet article décrit un capteur à fibres optiques de gaz carbonique par absorption moléculaire dans l'infrarouge moyen (4,3 μm) correspondant au mode fondamental ν3. La liaison entre le site de mesure et le site de contrôle est assurée par un fibre optique standard 50/125 après une transposition de longueur d'onde de 4,3 μm à 860 nm par opto-alimentation. La simulation de l'absorption a été obtenue par modélisation originale du spectre d'absorption et l'établissement des courbes d'étalonnage prévoit une marge d'erreur minimale de 100 μbar, ce qui est suffisant pour l'application du dispositif à la régulation de taux CO{2} dans les serres agricoles enrichies par de gaz.

  14. Poly (3-hydroxybutyrate-co-15 mol% 3hydroxyhexanoate)/ZnO nanocomposites by solvent casting method: a study of optical, surface, and thermal properties

    NASA Astrophysics Data System (ADS)

    Vishnu Chandar, J.; Shanmugan, S.; Mutharasu, D.; Azlan, A. A.

    2017-01-01

    Biopolymer nanocomposites are gaining interest due to their biodegradable and biocompatible nature, with exceptional properties which are superior to those of pure polymer and that can be used as a replacement for petroleum-based plastics. Pure poly (3-hydroxybutyrate-co-15 mol% 3hydroxyhexanoate) [P(3HB-co-15 mol% 3HHx)] and ZnO nanoparticles (NPs) reinforced P(3HB-co-15 mol% 3HHx) composite films were prepared and their morphological, optical, and thermal analyses were carried out to study the effect of ZnO NPs on P(3HB-co-15 mol% 3HHx) copolymer. From optical analysis, a strong absorbance peak at ˜358 nm with high intensity for 5%ZnO NPs reinforced P(3HB-co-15 mol% 3HHx) composite sample was observed. Nano-sized particles and their increased trend with increased ZnO NPs concentration were confirmed by UV-Vis spectral analysis. In addition to that, ZnO NPs reduced the reflectance behaviour of P(3HB-co-15 mol% 3HHx) copolymer in the UV region. Field emission scanning electron microscopy analysis evidenced that the pore numbers and their size in the composite matrix was decreased with increased ZnO NPs concentration. Improved thermal stability and melting temperature of the copolymer matrix was confirmed by thermogravimetric analysis and differential scanning calorimetry analysis, respectively. ZnO NPs acted as a retarding agent and showed a low degree of crystallinity (X c ) and enthalpy of melting (ΔH M ). From these observations, ZnO NPs reinforced P(3HB-co-15 mol% 3HHx) composites can be integrated with suitable resin and can be used as an LED encapsulant to block UV rays. They can also be used as a UV blocking coating material in the glass, plastic, and textile industries, for NIR shielding and food packaging applications.

  15. Efficient production of L-lactic acid by newly isolated thermophilic Bacillus coagulans WCP10-4 with high glucose tolerance.

    PubMed

    Zhou, Xingding; Ye, Lidan; Wu, Jin Chuan

    2013-05-01

    A thermophilic Bacillus coagulans WCP10-4 with tolerance to high concentration of glucose was isolated from soil and used to produce optically pure L-lactic acid from glucose and starch. In batch fermentation at pH 6.0, 240 g/L of glucose was completely consumed giving 210 g/L of L-lactic acid with a yield of 95 % and a productivity of 3.5 g/L/h. In simultaneous saccharification and fermentation at 50 °C without sterilizing the medium, 200 g/L of corn starch was completely consumed producing 202.0 g/L of L-lactic acid. To the best of our knowledge, this strain shows the highest osmotic tolerance to glucose among the strains ever reported for lactic acid production. This is the first report of simultaneous saccharification and fermentation of starch for lactic acid production under a non-sterilized condition.

  16. Relaxation magnétique nucléaire du carbone-13 et dynamique des molécules de chlorpromazine associées en solution aqueuse

    NASA Astrophysics Data System (ADS)

    Compère, S.; Thévand, A.

    1998-02-01

    13C relaxation times and heteronuclear NOE enhancements have been measured for chlorpromazine hydrochloride salt in chloroform and water. The dipolar contribution to 13C ^1H spin systems relaxation rates were extracted and allowed us to characterize the molecular reorientation in the two solvents. The correlation times are on either side of “T1 minimum". The values agree with the size of the molecule and show an association by stacking of 11 monomeric entities. Les temps de relaxation des 13C et les accroissements par effet Overhauser 1Hto13C ont été mesurés parallèlement sur la molécule de chlorhydrate de chlorpromazine non associée dans le chloroforme et auto-associée dans l'eau. L'extraction de la contribution dipolaire aux constantes de vitesse de relaxation des systèmes 13C 1H de la molécule a permis de caractériser la réorientation de la molécule dans les deux cas. Les temps de corrélation obtenus qui se situent de part et d'autre du “T1 minimum" sont en accord avec la taille de la molécule isolée et montrent que l'agrégat est formé par empilement de 11 molécules.

  17. BetaMol: A Molecular Modeling, Analysis and Visualization Software Based on the Beta-Complex and the Quasi-Triangulation

    NASA Astrophysics Data System (ADS)

    Cho, Youngsong; Kim, Jae-Kwan; Ryu, Joonghyun; Won, Chung-In; Kim, Chong-Min; Kim, Donguk; Kim, Deok-Soo

    Molecular shape is one of the most critical factors that determines molecular function. Therefore, it is frequently desirable to understand geometric characteristics of a molecule more precisely and efficiently. In this paper, we introduce the BetaMol, a molecular modeling, analysis, and visualization software based on the recent theory of the beta-complex and the quasi-triangulation that are derived from the Voronoi diagram of three-dimensional spherical atoms. The powerful features of the BetaMol are solely based on a unified, single framework of the mathematically rigorous and computationally efficient beta-complex theory. The BetaMol is implemented in the standard C++ language with OpenGL graphics library and freely available at Voronoi Diagram Research Center web site (http://voronoi.hanyang.ac.kr).

  18. Thermal conductivity of ZrO2-4mol%Y2O3 thin coatings by pulsed thermal imaging method

    SciTech Connect

    Jang, Byung-Koog; Sun, Jiangang; Kim, Seongwon; Oh, Yoon-Suk; Lee, Sung-Min; Kim, Hyung-Tae

    2015-12-01

    Thin ZrO2-4mol% Y2O3 coatings were deposited onto ZrO2 substrates by electron beam-physical vapor deposition. The coated samples revealed a feather-like columnar microstructure. The main phase of the ZrO2-4mol% Y2O3 coatings was the tetragonal phase. To evaluate the influence of the coating’s thickness on the thermal conductivity of thin ZrO2-4mol% Y2O3 coatings, the pulsed thermal imaging method was employed to obtain the thermal conductivity of the coating layer in the two-layer (coating and substrate) samples with thickness between 56 and 337 micrometers. The thermal conductivity of the coating layer was successfully evaluated and compared well with those obtained by the laser flash method for similar coatings. The thermal conductivity of coatings shows an increasing tendency with an increase in the coating’s thickness.

  19. EPR Spectroscopy of MolB2C2-A Reveals Mechanism of Transport for a Bacterial Type II Molybdate Importer*♦

    PubMed Central

    Rice, Austin J.; Alvarez, Frances J. D.; Schultz, Kathryn M.; Klug, Candice S.; Davidson, Amy L.; Pinkett, Heather W.

    2013-01-01

    In bacteria, ATP-binding cassette (ABC) transporters are vital for the uptake of nutrients and cofactors. Based on differences in structure and activity, ABC importers are divided into two types. Type I transporters have been well studied and employ a tightly regulated alternating access mechanism. Less is known about Type II importers, but much of what we do know has been observed in studies of the vitamin B12 importer BtuC2D2. MolB2C2 (formally known as HI1470/71) is also a Type II importer, but its substrate, molybdate, is ∼10-fold smaller than vitamin B12. To understand mechanistic differences among Type II importers, we focused our studies on MolBC, for which alternative conformations may be required to transport its relatively small substrate. To investigate the mechanism of MolBC, we employed disulfide cross-linking and EPR spectroscopy. From these studies, we found that nucleotide binding is coupled to a conformational shift at the periplasmic gate. Unlike the larger conformational changes in BtuCD-F, this shift in MolBC-A is akin to unlocking a swinging door: allowing just enough space for molybdate to slip into the cell. The lower cytoplasmic gate, identified in BtuCD-F as “gate I,” remains open throughout the MolBC-A mechanism, and cytoplasmic gate II closes in the presence of nucleotide. Combining our results, we propose a peristaltic mechanism for MolBC-A, which gives new insight in the transport of small substrates by a Type II importer. PMID:23709218

  20. Evaluation of MolYsis™ Complete5 DNA extraction method for detecting Staphylococcus aureus DNA from whole blood in a sepsis model using PCR/pyrosequencing.

    PubMed

    McCann, Chase D; Jordan, Jeanne A

    2014-04-01

    Bacterial bloodstream infections (BSI) and ensuing sepsis are important causes of morbidity and mortality. Early diagnosis and rapid treatment with appropriate antibiotics are vital for improving outcome. Nucleic acid amplification of bacteria directly from whole blood has the potential of providing a faster means of diagnosing BSI than automated blood culture. However, effective DNA extraction of commonly low levels of bacterial target from whole blood is critical for this approach to be successful. This study compared the Molzyme MolYsis™ Complete5 DNA extraction method to a previously described organic bead-based method for use with whole blood. A well-characterized Staphylococcus aureus-induced pneumonia model of sepsis in canines was used to provide clinically relevant whole blood samples. DNA extracts were assessed for purity and concentration and analyzed for bacterial rRNA gene targets using PCR and sequence-based identification. Both extraction methods yielded relatively pure DNA with median A260/280 absorbance ratios of 1.71 (MolYsis™) and 1.97 (bead-based). The organic bead-based extraction method yielded significantly higher average DNA concentrations (P<0.05) at each time point throughout the experiment, closely correlating with changes observed in white blood cell (WBC) concentrations during this same time period, while DNA concentrations of the MolYsis™ extracts closely mirrored quantitative blood culture results. Overall, S. aureus DNA was detected from whole blood samples in 70.7% (58/82) of MolYsis™ DNA extracts, and in 59.8% (49/82) of organic bead-based extracts, with peak detection rates seen at 48h for both MolYsis™ (87.0%) and organic bead-based (82.6%) methods. In summary, the MolYsis™ Complete5 DNA extraction kit proved to be the more effective method for isolating bacterial DNA directly from extracts made from whole blood.

  1. Evaluation of MolYsis™ Complete5 DNA Extraction Method for Detecting Staphylococcus aureus DNA from Whole Blood in a Sepsis Model Using PCR/Pyrosequencing

    PubMed Central

    McCann, Chase D.; Jordan, Jeanne A.

    2014-01-01

    Bacterial bloodstream infections (BSI) and ensuing sepsis are important causes of morbidity and mortality. Early diagnosis and rapid treatment with appropriate antibiotics are vital for improving outcome. Nucleic acid amplification of bacteria directly from whole blood has the potential of providing a faster means of diagnosing BSI than automated blood culture. However, effective DNA extraction of commonly low levels of bacterial target from whole blood is critical for this approach to be successful. This study compared the Molzyme MolYsis™ Complete5 DNA extraction method to a previously described organic bead-based method for use with whole blood. A well-characterized S. aureus-induced pneumonia model of sepsis in canines was used to provide clinically relevant whole blood samples. DNA extracts were assessed for purity and concentration and analyzed for bacterial rRNA gene targets using PCR and sequence-based identification. Both extraction methods yielded relatively pure DNA with median A260/280 absorbance ratios of 1.71 (MolYsis™) and 1.97 (bead-based). The organic bead-based extraction method yielded significantly higher average DNA concentrations (P <0.05) at each time point throughout the experiment, closely correlating with changes observed in white blood cell (WBC) concentrations during this same time period, while DNA concentrations of the MolYsis™ extracts closely mirrored quantitative blood culture results. Overall, S. aureus DNA was detected from whole blood samples in 70.7% (58/82) of MolYsis™ DNA extracts, and in 59.8% (49/82) of organic bead-based extracts, with peak detection rates seen at 48 h for both MolYsis™ (87.0%) and organic bead-based (82.6%) methods. In summary, the MolYsis™ Complete5 DNA extraction kit proved to be the more effective method for isolating bacterial DNA directly from extracts made from whole blood. PMID:24503182

  2. Influence of Fine Powder Feedstock (-10 + 2 μm) on the HVOF Spraying Characteristics, Coating Morphology, and Properties of WC-CoCr 86-10-4

    NASA Astrophysics Data System (ADS)

    Tillmann, W.; Nebel, J.; Piotrowski, W.

    2013-03-01

    The use of fine feedstock powder can extend the feasibility and scope of HVOF coatings to new fields of applications. Especially for the purpose of near-net-shape coatings, these powders facilitate homogeneous layer morphologies, and smooth coating surfaces. However, the small particle sizes also lead to several challenges. One major issue is the in-flight behavior which is distinctly affected by the low mass and relatively large specific surface of the particles. In this paper, the in-flight and coating characteristics of WC-CoCr 86-10-4 (-10 + 2 μm) were investigated. It was determined that the fine powder feedstock shows a high sensitivity to the gas flow, velocity, and temperature of the spray jet. Because of their low mass inertia, their velocity, for example, is actually influenced by local pressure nodes (shock diamonds) in the supersonic flow. Additionally, the relatively large specific surface of the particles promotes partial overheating and degradation. Nevertheless, the morphological and mechanical properties of the sprayed layer are hardly affected. In fact, the coatings feature a superior surface roughness, porosity, hardness, and wear resistance.

  3. Crystal structure of a 2:1 piroxicam–gentisic acid co-crystal featuring neutral and zwitterionic piroxicam mol­ecules

    PubMed Central

    Horstman, Elizabeth M.; Bertke, Jeffery A.; Woods, Toby J.; Kenis, Paul J. A.

    2016-01-01

    A new 2:1 co-crystal of piroxicam and gentisic acid [systematic name: 4-hy­droxy-1,1-dioxo-N-(pyridin-2-yl)-2H-1λ6,2-benzo­thia­zine-3-carboxamide–2-(4-oxido-1,1-dioxo-2H-1λ6,2-benzo­thia­zine-3-amido)­pyridin-1-ium–2,5-di­hydroxy­benzoic acid, 2C15H13N3O4S·C7H6O4] has been synthesized using a microfluidic platform and initially identified using Raman spectroscopy. In the co-crystal, one piroxicam mol­ecule is in its neutral form and an intra­molecular O—H⋯O hydrogen bond is observed. The other piroxicam mol­ecule is zwitterionic (proton transfer from the OH group to the pyridine N atom) and two intra­molecular N—H⋯O hydrogen bonds occur. The gentisic acid mol­ecule shows whole-mol­ecule disorder over two sets of sites in a 0.809 (2):0.191 (2) ratio. In the crystal, extensive hydrogen bonding between the components forms layers propagating in the ab plane. PMID:27980814

  4. Crystal structure of a 2:1 piroxicam-gentisic acid co-crystal featuring neutral and zwitterionic piroxicam mol-ecules.

    PubMed

    Horstman, Elizabeth M; Bertke, Jeffery A; Woods, Toby J; Kenis, Paul J A

    2016-12-01

    A new 2:1 co-crystal of piroxicam and gentisic acid [systematic name: 4-hy-droxy-1,1-dioxo-N-(pyridin-2-yl)-2H-1λ(6),2-benzo-thia-zine-3-carboxamide-2-(4-oxido-1,1-dioxo-2H-1λ(6),2-benzo-thia-zine-3-amido)-pyridin-1-ium-2,5-di-hydroxy-benzoic acid, 2C15H13N3O4S·C7H6O4] has been synthesized using a microfluidic platform and initially identified using Raman spectroscopy. In the co-crystal, one piroxicam mol-ecule is in its neutral form and an intra-molecular O-H⋯O hydrogen bond is observed. The other piroxicam mol-ecule is zwitterionic (proton transfer from the OH group to the pyridine N atom) and two intra-molecular N-H⋯O hydrogen bonds occur. The gentisic acid mol-ecule shows whole-mol-ecule disorder over two sets of sites in a 0.809 (2):0.191 (2) ratio. In the crystal, extensive hydrogen bonding between the components forms layers propagating in the ab plane.

  5. RD2-MolPack-Chim3, a Packaging Cell Line for Stable Production of Lentiviral Vectors for Anti-HIV Gene Therapy

    PubMed Central

    Stornaiuolo, Anna; Piovani, Bianca Maria; Bossi, Sergio; Zucchelli, Eleonora; Corna, Stefano; Salvatori, Francesca; Mavilio, Fulvio; Bordignon, Claudio; Rizzardi, Gian Paolo

    2013-01-01

    Abstract Over the last two decades, several attempts to generate packaging cells for lentiviral vectors (LV) have been made. Despite different technologies, no packaging clone is currently employed in clinical trials. We developed a new strategy for LV stable production based on the HEK-293T progenitor cells; the sequential insertion of the viral genes by integrating vectors; the constitutive expression of the viral components; and the RD114-TR envelope pseudotyping. We generated the intermediate clone PK-7 expressing constitutively gag/pol and rev genes and, by adding tat and rd114-tr genes, the stable packaging cell line RD2-MolPack, which can produce LV carrying any transfer vector (TV). Finally, we obtained the RD2-MolPack-Chim3 producer clone by transducing RD2-MolPack cells with the TV expressing the anti-HIV transgene Chim3. Remarkably, RD114-TR pseudovirions have much higher potency when produced by stable compared with transient technology. Most importantly, comparable transduction efficiency in hematopoietic stem cells (HSC) is obtained with 2-logs less physical particles respect to VSV-G pseudovirions produced by transient transfection. Altogether, RD2-MolPack technology should be considered a valid option for large-scale production of LV to be used in gene therapy protocols employing HSC, resulting in the possibility of downsizing the manufacturing scale by about 10-fold in respect to transient technology. PMID:23767932

  6. RD-MolPack technology for the constitutive production of self-inactivating lentiviral vectors pseudotyped with the nontoxic RD114-TR envelope

    PubMed Central

    Marin, Virna; Stornaiuolo, Anna; Piovan, Claudia; Corna, Stefano; Bossi, Sergio; Pema, Monika; Giuliani, Erica; Scavullo, Cinzia; Zucchelli, Eleonora; Bordignon, Claudio; Rizzardi, Gian Paolo; Bovolenta, Chiara

    2016-01-01

    To date, gene therapy with transiently derived lentivectors has been very successful to cure rare infant genetic diseases. However, transient manufacturing is unfeasible to treat adult malignancies because large vector lots are required. By contrast, stable manufacturing is the best option for high-incidence diseases since it reduces the production cost, which is the major current limitation to scale up the transient methods. We have previously developed the proprietary RD2-MolPack technology for the stable production of second-generation lentivectors, based on the RD114-TR envelope. Of note, opposite to vesicular stomatitis virus glycoprotein (VSV-G) envelope, RD114-TR does not need inducible expression thanks to lack of toxicity. Here, we present the construction of RD2- and RD3-MolPack cells for the production of self-inactivating lentivectors expressing green fluorescent protein (GFP) as a proof-of-concept of the feasibility and safety of this technology before its later therapeutic exploitation. We report that human T lymphocytes transduced with self-inactivating lentivectors derived from RD3-MolPack cells or with self-inactivating VSV-G pseudotyped lentivectors derived from transient transfection show identical T-cell memory differentiation phenotype and comparable transduction efficiency in all T-cell subsets. RD-MolPack technology represents, therefore, a straightforward tool to simplify and standardize lentivector manufacturing to engineer T-cells for frontline immunotherapy applications. PMID:27222840

  7. Electronic and vibrational properties of yttria-stabilised zirconia from first-principles for 10-40 mol% Y2O3

    NASA Astrophysics Data System (ADS)

    Cousland, G. P.; Cui, X. Y.; Ringer, S.; Smith, A. E.; Stampfl, A. P. J.; Stampfl, C. M.

    2014-11-01

    Density-functional theory calculations are performed to investigate the electronic and vibrational density-of-states (DOS) for a series of recently predicted stable and metastable structures of yttria-stabilised zirconia (YSZ) with yttria (Y2O3) concentrations of 14, 17 and 20 mol%. Analogous quantities are also studied for the so-called δ-phase, which forms for 40 mol% yttria, as well as for model structures with ≈10.3 mol% yttria. These calculated results, together with those for the cubic, tetragonal and monoclinic phases of ZrO2, afford a comparison of structural, electronic and vibrational properties as a function of yttria concentration. With increasing yttria content, the electronic DOS exhibit a decrease in the valence band-width (of about 2.0 eV relative to the cubic phase) and a corresponding increase of the band-gap of 0.73 eV (from cubic to 40 mol% yttria containing ZrO2). Regarding the vibrational DOS (vDOS), the addition of yttria causes the peaks in the vDOS of ZrO2 to become less distinct, reflecting the more dense occupation of states due to the larger number of atoms in each primitive cell, and to the lower symmetry. The vDOS of the various YSZ structures appear qualitatively similar with contributions from O atoms spanning the whole frequency range and cation related contributions present for frequencies < 40 - 45 meV. With increasing yttria content, more Zr atoms become seven-fold coordinated as in monoclinic ZrO2, concominantly the vDOS increasingly resembles that of m-ZrO2, but with notable contributions from Y atoms, which has a main peak at about 17 meV, similar to that of Zr atoms.

  8. W2X and W3X-L: Cost-Effective Approximations to W2 and W4 with kJ mol(-1) Accuracy.

    PubMed

    Chan, Bun; Radom, Leo

    2015-05-12

    We have formulated the W2X and W3X-L protocols as cost-effective alternatives to W2 and W3/W4, respectively, and to supplement our previously developed set of W1X and W3X procedures. The W2X procedure provides an accurate approximation to the all-electron scalar-relativistic CCSD(T)/CBS energy, with a mean absolute deviation (MAD) of 0.6 kJ mol(-1) from benchmark energies provided by the CCSD(T) component in the W4 protocol. Such a performance is comparable to that of W2w (0.5 kJ mol(-1)) but comes at a significantly lower cost. Comparison of computational requirements shows that W2X should be applicable to systems that can be treated by the W1w method. Thus, W2X provides an accurate means for the treatment of medium-sized systems such as naphthalene. For the calculation of post-CCSD(T) effects, we propose a slight modification to the method used in our previously devised W3X procedure. Our new W3-type protocol (W3X-L) combines this new post-CCSD(T) treatment with our new W2X procedure. It has an MAD from benchmark values of 0.8 kJ mol(-1) for the W4-11 set, which is comparable to that for the computationally more demanding W3.2 method (0.6 kJ mol(-1)). However, the use of the even relatively modest post-CCSD(T) calculations in W3X-L still represents a computational bottleneck, and this currently restricts its application to systems up to the size of benzene with our current computing resources.

  9. Complexation of mercury(II) with 1-Phenyl-2,3-dimethylpyrazoline-5-thione in 0.1 mol/L HNO3 at 273-338 K

    NASA Astrophysics Data System (ADS)

    Beknazarova, N. S.; Shoalifov, Dzh. O.; Amindzhanov, A. A.; Safarmamadov, S. M.

    2016-12-01

    The complexation of mercury(II) with 1-phenyl-2,3-dimethylpyrazoline-5-thione is studied by means of potentiometry in 0.1 mol/L HNO3 at 273-338 K. The composition of the complexes is determined and their stepwise stability constants are calculated. A pattern is found in altering the stepwise stability constants as the temperature and number of attached 1-phenyl-2,3-dimethylpyrazoline-5-thione molecules rise.

  10. Development of a 100 nmol mol(-1) propane-in-air SRM for automobile-exhaust testing for new low-emission requirements.

    PubMed

    Rhoderick, George C

    2007-04-01

    New US federal low-level automobile emission requirements, for example zero-level-emission vehicle (ZLEV), for hydrocarbons and other species, have resulted in the need by manufacturers for new certified reference materials. The new emission requirement for hydrocarbons requires the use, by automobile manufacturing testing facilities, of a 100 nmol mol(-1) propane in air gas standard. Emission-measurement instruments are required, by federal law, to be calibrated with National Institute of Standards and Technology (NIST) traceable reference materials. Because a NIST standard reference material (SRM) containing 100 nmol mol(-1) propane was not available, the US Environmental Protection Agency (EPA) and the Automobile Industry/Government Emissions Research Consortium (AIGER) requested that NIST develop such an SRM. A cylinder lot of 30 gas mixtures containing 100 nmol mol(-1) propane in air was prepared in 6-L aluminium gas cylinders by a specialty gas company and delivered to the Gas Metrology Group at NIST. Another mixture, contained in a 30-L aluminium cylinder and included in the lot, was used as a lot standard (LS). Using gas chromatography with flame-ionization detection all 30 samples were compared to the LS to obtain the average of six peak-area ratios to the LS for each sample with standard deviations of <0.31%. The average sample-to-LS ratio determinations resulted in a range of 0.9828 to 0.9888, a spread of 0.0060, which corresponds to a relative standard deviation of 0.15% of the average for all 30 samples. NIST developed its first set of five propane in air primary gravimetric standards covering a concentration range 91 to 103 nmol mol(-1) with relative uncertainties of 0.15%. This new suite of propane gravimetric standards was used to analyze and assign a concentration value to the SRM LS. On the basis of these data each SRM sample was individually certified, furnishing the desired relative expanded uncertainty of +/-0.5%. Because automobile companies

  11. Electrets used in measuring rocket exhaust effluents from the space shuttle's solid rocket booster during static test firing, DM-3

    NASA Technical Reports Server (NTRS)

    Susko, M.

    1979-01-01

    The purpose of this experimental research was to compare Marshall Space Flight Center's electrets with Thiokol's fixed flow air samplers during the Space Shuttle Solid Rocket Booster Demonstration Model-3 static test firing on October 19, 1978. The measurement of rocket exhaust effluents by Thiokol's samplers and MSFC's electrets indicated that the firing of the Solid Rocket Booster had no significant effect on the quality of the air sampled. The highest measurement by Thiokol's samplers was obtained at Plant 3 (site 11) approximately 8 km at a 113 degree heading from the static test stand. At sites 11, 12, and 5, Thiokol's fixed flow air samplers measured 0.0048, 0.00016, and 0.00012 mg/m3 of CI. Alongside the fixed flow measurements, the electret counts from X-ray spectroscopy were 685, 894, and 719 counts. After background corrections, the counts were 334, 543, and 368, or an average of 415 counts. An additional electred, E20, which was the only measurement device at a site approximately 20 km northeast from the test site where no power was available, obtained 901 counts. After background correction, the count was 550. Again this data indicate there was no measurement of significant rocket exhaust effluents at the test site.

  12. Managing and delivering of 3D geo data across institutions has a web based solution - intermediate results of the project GeoMol.

    NASA Astrophysics Data System (ADS)

    Gietzel, Jan; Schaeben, Helmut; Gabriel, Paul

    2014-05-01

    The increasing relevance of geological information for policy and economy at transnational level has recently been recognized by the European Commission, who has called for harmonized information related to reserves and resources in the EU Member States. GeoMol's transnational approach responds to that, providing consistent and seamless 3D geological information of the Alpine Foreland Basins based on harmonized data and agreed methodologies. However, until recently no adequate tool existed to ensure full interoperability among the involved GSOs and to distribute the multi-dimensional information of a transnational project facing diverse data policy, data base systems and software solutions. In recent years (open) standards describing 2D spatial data have been developed and implemented in different software systems including production environments for 2D spatial data (like regular 2D-GI-Systems). Easy yet secured access to the data is of upmost importance and thus priority for any spatial data infrastructure. To overcome limitations conditioned by highly sophisticated and platform dependent geo modeling software packages functionalities of a web portals can be utilized. Thus, combining a web portal with a "check-in-check-out" system allows distributed organized editing of data and models but requires standards for the exchange of 3D geological information to ensure interoperability. Another major concern is the management of large models and the ability of 3D tiling into spatially restricted models with refined resolution, especially when creating countrywide models . Using GST ("Geosciences in Space and Time") developed initially at TU Bergakademie Freiberg and continuously extended by the company GiGa infosystems, incorporating these key issues and based on an object-relational data model, it is possible to check out parts or whole models for edits and check in again after modification. GST is the core of GeoMol's web-based collaborative environment designed to

  13. Development of 11-Plex MOL-PCR Assay for the Rapid Screening of Samples for Shiga Toxin-Producing Escherichia coli

    PubMed Central

    Woods, Travis A.; Mendez, Heather M.; Ortega, Sandy; Shi, Xiaorong; Marx, David; Bai, Jianfa; Moxley, Rodney A.; Nagaraja, T. G.; Graves, Steven W.; Deshpande, Alina

    2016-01-01

    Strains of Shiga toxin-producing Escherichia coli (STEC) are a serious threat to the health, with approximately half of the STEC related food-borne illnesses attributable to contaminated beef. We developed an assay that was able to screen samples for several important STEC associated serogroups (O26, O45, O103, O104, O111, O121, O145, O157) and three major virulence factors (eae, stx1, stx2) in a rapid and multiplexed format using the Multiplex oligonucleotide ligation-PCR (MOL-PCR) assay chemistry. This assay detected unique STEC DNA signatures and is meant to be used on samples from various sources related to beef production, providing a multiplex and high-throughput complement to the multiplex PCR assays currently in use. Multiplex oligonucleotide ligation-PCR (MOL-PCR) is a nucleic acid-based assay chemistry that relies on flow cytometry/image cytometry and multiplex microsphere arrays for the detection of nucleic acid-based signatures present in target agents. The STEC MOL-PCR assay provided greater than 90% analytical specificity across all sequence markers designed when tested against panels of DNA samples that represent different STEC serogroups and toxin gene profiles. This paper describes the development of the 11-plex assay and the results of its validation. This highly multiplexed, but more importantly dynamic and adaptable screening assay allows inclusion of additional signatures as they are identified in relation to public health. As the impact of STEC associated illness on public health is explored additional information on classification will be needed on single samples; thus, this assay can serve as the backbone for a complex screening system. PMID:27630828

  14. Cloning of pMOL28-encoded nickel resistance genes and expression of the genes in Alcaligenes eutrophus and Pseudomonas spp.

    PubMed Central

    Siddiqui, R A; Benthin, K; Schlegel, H G

    1989-01-01

    The 163-kilobase-pair (kb) plasmid pMOL28, which determines inducible resistance to nickel, cobalt, chromate, and mercury salts in its native host Alcaligenes eutrophus CH34, was transferred to a derivative of A. eutrophus H16 and subjected to cloning procedures. After Tn5 transposon mutagenesis, restriction endonuclease analysis, and DNA-DNA hybridization, two DNA fragments, a 9.5-kb KpnI fragment and a 13.5-kb HindIII fragment (HKI), were isolated. HKI contained EK1, the KpnI fragment, as a subfragment flanked on both sides by short regions. Both fragments were ligated into the suicide vector pSUP202, the broad-host-range vector pVK101, and pUC19. Both fragments restored a nickel-sensitive Tn5 mutant to full nickel and cobalt resistance. The hybrid plasmid pVK101::HKI expressed full nickel resistance in all nickel-sensitive derivatives, either pMOL28-deficient or -defective, of the native host CH34. The hybrid plasmid pVK101::HKI also conferred nickel and cobalt resistance to A. eutrophus strains H16 and JMP222, Alcaligenes hydrogenophilus, Pseudomonas putida, and Pseudomonas oleovorans, but to a lower level of resistance. In all transconjugants the metal resistances coded by pVK101::HKI were expressed constitutively rather than inducibly. The hybrid plasmid metal resistance was not expressed in Escherichia coli. DNA sequences responsible for nickel resistance in newly isolated strains showed homology to the cloned pMOL28-encoded nickel and cobalt resistance determinant. Images PMID:2549012

  15. Development of 11-Plex MOL-PCR Assay for the Rapid Screening of Samples for Shiga Toxin-Producing Escherichia coli.

    PubMed

    Woods, Travis A; Mendez, Heather M; Ortega, Sandy; Shi, Xiaorong; Marx, David; Bai, Jianfa; Moxley, Rodney A; Nagaraja, T G; Graves, Steven W; Deshpande, Alina

    2016-01-01

    Strains of Shiga toxin-producing Escherichia coli (STEC) are a serious threat to the health, with approximately half of the STEC related food-borne illnesses attributable to contaminated beef. We developed an assay that was able to screen samples for several important STEC associated serogroups (O26, O45, O103, O104, O111, O121, O145, O157) and three major virulence factors (eae, stx 1 , stx 2) in a rapid and multiplexed format using the Multiplex oligonucleotide ligation-PCR (MOL-PCR) assay chemistry. This assay detected unique STEC DNA signatures and is meant to be used on samples from various sources related to beef production, providing a multiplex and high-throughput complement to the multiplex PCR assays currently in use. Multiplex oligonucleotide ligation-PCR (MOL-PCR) is a nucleic acid-based assay chemistry that relies on flow cytometry/image cytometry and multiplex microsphere arrays for the detection of nucleic acid-based signatures present in target agents. The STEC MOL-PCR assay provided greater than 90% analytical specificity across all sequence markers designed when tested against panels of DNA samples that represent different STEC serogroups and toxin gene profiles. This paper describes the development of the 11-plex assay and the results of its validation. This highly multiplexed, but more importantly dynamic and adaptable screening assay allows inclusion of additional signatures as they are identified in relation to public health. As the impact of STEC associated illness on public health is explored additional information on classification will be needed on single samples; thus, this assay can serve as the backbone for a complex screening system.

  16. Preparation of 15 mol% YO 1.5-doped ThO 2 disk electrolytes by a polymeric gel-combustion method

    NASA Astrophysics Data System (ADS)

    Arul Antony, S.; Nagaraja, K. S.; Sreedharan, O. M.

    2001-06-01

    A hybrid of polymeric gel and auto-combustion techniques was adapted for the synthesis and lower temperature sintering of 15 mol% YO 1.5-doped thoria (15 YDT) homogeneous solid solutions at 1350°C. The YDT discs so prepared were of density better than 99% theoretical and the cubic cell parameter was ao=558.15(±0.13) pm in close agreement with 557.8 pm recently reported as high quality data in JCPDS confirming the validity of the anion vacancy model for Th 0.85Y 0.15O 1.925.

  17. Chemico-biological interaction of Etravirine and its β-Cyclodextrin complex with macromolecular targets.

    PubMed

    Yousuf, Sameena; Natesan, Sudha; Enoch, Israel V M V

    2017-04-01

    The interaction of etravirine with β-cyclodextrin is analyzed by UV-visible absorption, infrared, fluorescence, nuclear magnetic resonance, two-dimensional rotational frame nuclear Overhauser effect spectroscopy, and molecular modeling studies. The 4-hydroxy-3, 5-dimethylbenzonitrile moiety is found to take part in the binding. The stoichiometry of the inclusion complex of ET with β-CD is 1:1 with the binding constant of 2.03 × 10(3) mol(-1) dm(3). The binding of ET with calf thymus DNA (ctDNA) and bovine serum albumin (BSA) protein is investigated in the presence and the absence of β-CD. Fluorescence enhancement is observed during the binding of ET with ctDNA in the absence of β-CD, whereas in the presence of β-CD, fluorescence quenching is observed. The binding constants of the binding of ET and ET-β-CD to ctDNA are 7.84 × 10(4) and 4.38 × 10(4mol(-1) dm(3), respectively. The binding constant of the binding of ET and ET-β-CD to BSA are 3.14 × 10(4) and 1.6396 × 10(4mol(-1) dm(3), respectively. The apparent binding constants between ET-β-CD complex and ctDNA or BSA protein decreases significantly. The numbers of binding sites of interaction of ET with BSA protein and the binding distance between BSA protein and ET the absence and the presence of β-CD differ. β-CD modulates the binding of ET with the macromolecular targets.

  18. VSDMIP 1.5: an automated structure- and ligand-based virtual screening platform with a PyMOL graphical user interface

    NASA Astrophysics Data System (ADS)

    Cabrera, Álvaro Cortés; Gil-Redondo, Rubén; Perona, Almudena; Gago, Federico; Morreale, Antonio

    2011-09-01

    A graphical user interface (GUI) for our previously published virtual screening (VS) and data management platform VSDMIP (Gil-Redondo et al. J Comput Aided Mol Design, 23:171-184, 2009) that has been developed as a plugin for the popular molecular visualization program PyMOL is presented. In addition, a ligand-based VS module (LBVS) has been implemented that complements the already existing structure-based VS (SBVS) module and can be used in those cases where the receptor's 3D structure is not known or for pre-filtering purposes. This updated version of VSDMIP is placed in the context of similar available software and its LBVS and SBVS capabilities are tested here on a reduced set of the Directory of Useful Decoys database. Comparison of results from both approaches confirms the trend found in previous studies that LBVS outperforms SBVS. We also show that by combining LBVS and SBVS, and using a cluster of 100 modern processors, it is possible to perform complete VS studies of several million molecules in less than a month. As the main processes in VSDMIP are 100% scalable, more powerful processors and larger clusters would notably decrease this time span. The plugin is distributed under an academic license upon request from the authors.

  19. Deformation of as-cast LiF-22 mol pct CaF2 hypereutectic salt between 500 and 1015 K

    NASA Technical Reports Server (NTRS)

    Raj, S. V.; Whittenberger, J. D.

    1990-01-01

    Results are presented on compression tests conducted on as-cast LiF-22 mol pct CaF2 hypereutectic specimens at nominal strain rates between 1.8 x 10 to the -6th/sec and 0.25/sec over the temperature range 500-1015 K. In all instances, the stress-strain curves showed broad maxima, with negative strain-hardening rates after the peak stress sigma(max). It was found that, at low temperatures and high stresses, the CaF2 lamellae are rigid while the LiF matrix exhibits extensive transgranular cavitation, while at high temperatures and low stresses the CaF2 lamellae break down and spheroidize while the LiF matrix does not cavitate. It was concluded that the mechanical properties of the as-cast hypereutectic LiF-22 mol pct CaF2 are governed by the rate of deformation of the CaF2 phase. It is suggested that, for thermal energy storage applications, a spheroidal microstructure is more desirable than a lamellar structure.

  20. Comparison of the bulk geochemical features and thermal reactivity of kerogens from Mol (Boom Clay), Bure (Callovo-Oxfordian argillite) and Tournemire (Toarcian shales) underground research laboratories.

    PubMed

    Deniau, I; Devol-Brown, I; Derenne, S; Behar, F; Largeau, C

    2008-01-25

    Deep argillaceous formations are potential repositories for the long-term disposal of nuclear waste because of their low permeability and high sorption capacity with respect to radioelements and heavy metals. Such sedimentary rocks contain organic matter, mostly macromolecular and insoluble (kerogen). Upon temperature elevation related to high-level long-lived radioactive waste disposal, the kerogen may release significant quantities of gaseous and liquid effluents, especially oxygen-containing ones, which may influence the ability of the clay to retain radionuclides. The aim of the present study is to assess the global geochemical features and the thermal reactivity of the kerogens isolated from samples collected in the Bure and Tournemire sites, France (Callovo-Oxfordian Clay and Toarcian Shales, respectively) and to draw comparisons with data previously obtained for the Mol site, Belgium (Boom Clay). The study is based on a combination of elemental, spectroscopic (FTIR, solid state (13)C NMR) and pyrolytic (Rock-Eval pyrolysis, Curie point pyrolysis-gas chromatography/mass spectrometry) analyses. Different levels of maturity and resulting differences in the relative abundance of oxygen-containing groups were thus observed for the three kerogens. This is linked with differences in their ability to generate CO(2) and various oxygen-containing, low molecular weight, water-soluble compounds under thermal stress, decreasing from Mol to Bure and to Tournemire.

  1. The adenovirus E3 10.4K and 14.5K proteins, which function to prevent cytolysis by tumor necrosis factor and to down-regulate the epidermal growth factor receptor, are localized in the plasma membrane.

    PubMed Central

    Stewart, A R; Tollefson, A E; Krajcsi, P; Yei, S P; Wold, W S

    1995-01-01

    The adenovirus type 2 and 5 E3 10,400- and 14,500-molecular-weight (10.4K and 14.5K) proteins are both required to protect some cell lines from lysis by tumor necrosis factor and to down-regulate the epidermal growth factor receptor. We have shown previously that both 10.4K and 14.5K are integral membrane proteins and that 14.5K is phosphorylated and O glycosylated. The 10.4K protein coimmunoprecipitates with 14.5K, indicating that the two proteins function as a complex. Here we show, using immunofluorescence and two different cell surface-labeling techniques, that both proteins are localized in the plasma membrane. In addition, we show that trafficking of each protein to the plasma membrane depends on concomitant expression of the other protein. Finally, neither protein could be immunoprecipitated from conditioned media, indicating that neither is secreted. Taken together, these results suggest that the plasma membrane is the site at which 10.4K and 14.5K function to inhibit cytolysis by tumor necrosis factor and to down-regulate the epidermal growth factor receptor. PMID:7983708

  2. XPS and ToF-SIMS analysis of natural rubies and sapphires heat-treated in a reducing (5 mol% H 2/Ar) atmosphere

    NASA Astrophysics Data System (ADS)

    Achiwawanich, S.; James, B. D.; Liesegang, J.

    2008-12-01

    Surface effects on Mong Hsu rubies and Kanchanaburi sapphires after heat treatment in a controlled reducing atmosphere (5 mol% H 2/Ar) have been investigated using advanced surface science techniques including X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Visual appearance of the gemstones is clearly affected by the heat treatment in a reducing atmosphere. Kanchanaburi sapphires, in particular, exhibit Fe-containing precipitates after the heat treatment which have not been observed in previous studies under an inert atmosphere. Significant correlation between changes in visual appearance of the gemstones and variations in surface concentration of trace elements, especially Ti and Fe are observed. The XPS and ToF-SIMS results suggest that; (1) a reducing atmosphere affects the oxidation state of Fe; (2) dissociation of Fe-Ti interaction may occur during heat treatment.

  3. Structure and optical homogeneity of LiNbO{sub 3}:Zn (0.03–4.5 mol.%) crystals

    SciTech Connect

    Sidorov, Nikolay E-mail: tepl-na@chemy.kolasc.net.ru E-mail: Jovial1985@yandex.ru Tepljakova, Natalja E-mail: tepl-na@chemy.kolasc.net.ru E-mail: Jovial1985@yandex.ru Gabain, Aleksei E-mail: tepl-na@chemy.kolasc.net.ru E-mail: Jovial1985@yandex.ru Yanichev, Aleksander E-mail: tepl-na@chemy.kolasc.net.ru E-mail: Jovial1985@yandex.ru Palatnikov, Mikhail E-mail: tepl-na@chemy.kolasc.net.ru E-mail: Jovial1985@yandex.ru

    2014-11-14

    Structure and optical homogeneity of LiNbO{sub 3}:Zn (0.03–4.5 mol.%) crystals were searched by photoinduced light scattering and by Raman spectroscopy. The photorefractive effect depends on Zn{sup 2+} concentration nonmonotonically. Decrease of photorefractive effect is explained by decrease of structure defects with localized electrons. The Zn{sup 2+} cations replace structure defects Nb{sub Li} and Li{sub Nb}, trapping levels appear near the bottom of the conduction band and photo electrons recombine with emission under laser radiation. By the Raman spectra the area of the high structure order is found. In this area the own alternation, the alternation of impurity cations and the vacancies along the polar axis is almost perfect.

  4. X-ray diffraction study of the t-to-m phase transformation in 12-mol%-ceria-doped zirconia at low temperatures

    SciTech Connect

    Zhu, H.Y. . Dept. of Materials Science and Engineering)

    1994-09-01

    The t-to-m phase transformation in a 12-mol%-ceria-doped zirconia to subzero temperatures was studied in situ by XRD with a cryogenic sample stage. It was found that the t-to-m transformation continuously proceeded to 30 vol% as the temperature decreased to 125 K, when a burstlike transformation suddenly occurred with a transformation to 75 vol%. A preferred orientation of the ([bar 1]11)[sub m] plane parallel to the surface during the preburst transformation and XRD line broadening of both m and t phases after the burst were observed. The preburst transformation, which has not been revealed by previous dilatometry studies, is explained as surface martensitic transformation. This surface transformation occurs at higher temperature than the burstlike transformation due to less matrix constraint and the higher probability of nucleation.

  5. Contrôle de l'orientation et de l'alignement moléculaire par un train d'impulsions soudaines

    NASA Astrophysics Data System (ADS)

    Sugny, D.

    2006-10-01

    Les récents progrès technologiques dans le domaine des Lasers permettent d'envisager le contrôle de nombreux processus quantiques jouant un rôle dans une variété de problèmes s'étendant de la réactivité chimique à l'information quantique. Dans ce contexte, nous nous sommes intéressés au contrôle de l'orientation ou de l'alignement moléculaire en utilisant un train d'impulsions soudaines. Nous avons défini des états cibles qui maximisent à la fois l'orientation ou l'alignement et sa durée dans le temps et montré comment atteindre ces états à l'aide de stratégie systématique ou optimisée

  6. Comment on Neiser et al. Assessment of Dextran Antigenicity of Intravenous Iron Preparations with Enzyme-Linked Immunosorbent Assay (ELISA). Int. J. Mol. Sci. 2016, 17, 1185.

    PubMed

    Strom, Claes C; Andreasen, Hans B

    2017-01-10

    All IV iron complexes carry a risk of potentially fatal allergic type hypersensitivity reactions. The mechanism(s) behind these reactions is unknown but the limited data available suggests that classic IgE mediated allergy is exceedingly rare, if ever occurring. Iron-carbohydrate molecules are complex nano-particles and trying to reduce the risk of serious hypersensitivity to antibody binding of an artificial antibody seems meaningless. A recently published analysis of safety data from randomized clinical trials confirms the method reported by Neiser to be useless to predict reaction risk. In conclusion, the study by Neiser et al. is biased, contains no new information, and has no clinical relevance. We are concerned that the association of the authors with a commercial entity has caused a conflict of interest that biases not only the results, but the entire experimental setup against competitors. (Comment on Neiser et al. Int. J. Mol. Sci. 2016, 17, 1185, doi:10.3390/ijms17071185).

  7. Permeation of mixtures of four phenols through a supported liquid membrane in NaCl 1.0 mol/dm{sup 3} medium

    SciTech Connect

    Arana, G.; Borge, G.; Etxebarria, N.; Fernandez, L.A.

    1999-02-01

    The permeation of four phenols (phenol, 2-chlorophenol, 2-nitrophenol, and 2,4-dichlorophenol) through a supported liquid membrane has been studied in NaCl 1.0 mol/dm{sup 3} medium. The flux of each phenol was determined by measuring in real time the change of their concentration in the strip phase by making use of a fiber optic spectrophotometer and a multivariate calibration. The model for the permeation of phenol alone was first developed by making permeation experiments of a phenol, and then permeation studies of the mixture were carried out and the model was extended to those phenols. It was found that the permeation of a phenol is interfered with by the presence of other phenols.

  8. Determination of μmol l-1 level of iron (III) in natural waters and total iron in drugs by flow injection spectrophotometry

    PubMed Central

    Sahasrabuddhey, B.; Mishra, S.; Jain, A.; Verma, K. K.

    1999-01-01

    The equilibrium problems, characterized by recurring end-points, involved in the reaction of iron (III) with iodide make the batch iodometric determination of iron (III) unsuitable. Since the flow injection determination does not require attainment of steady state either for mixing of reagents or for the chemical reaction, the iodometric determination has been accurately and precisely performed using this technique in the present work. This method does not require any special reagent, including chelating agents or those which are loxic, and has a limit of detection of 0.2 μmol l-1 (11 μg l-1) of iron (III). The interference of fluoride has been avoided by adding zirconyl nitrate to the test sample solution, and of copper (II) by complex formation with 2-mercaptobenzoxazole. The method has been applied to determine iron (III) in natural waters, and total iron in drugs. PMID:18924838

  9. VizieR Online Data Catalog: ExoMol line lists for NaH and NaD (Rivlin+, 2015)

    NASA Astrophysics Data System (ADS)

    Rivlin, T.; Lodi, L.; Yurchenko, S. N.; Tennyson, J.; Le, Roy R. J.

    2015-05-01

    The data for each isotopologue are in two parts. The first, .states contains a list of rovibronic states. Each state is labelled with the total angular momentum, state degeneracy, vibrational quantum number, and an electronic state label (A/X). Each state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. A sample programme to generate synthetic spectra from the ExoMol format line lists can be obtained at www.exomol.com. (4 data files).

  10. Grupos españoles de cálculos ab initio de moléculas de interés astrofísico

    NASA Astrophysics Data System (ADS)

    Yáñez, M.

    Pocos campos de la química están tan bien adaptados a la modelización por medio de los métodos teóricos de la Química Cuántica como la Astroquímica y la Química de la Atmósfera, donde las interacciones moleculares son, generalmente, lo suficientemente pequeñas para que el modelo de molécula aislada funcione muy bien. En España son varios los grupos teóricos que dedican su esfuerzo de investigación, o parte de él, al estudio de moléculas o procesos de interés en Astrofísica o en atmósferas planetarias. Presentaremos diferentes ejemplos paradigmáticos de esta actividad en la que se exploran desde aspectos estructurales, hasta aspectos espectroscópicos y dinámicos. Entre los últimos, cabe destacar estudios en los que se demuestra la importancia de procesos a dos estados, prohibidos por espín, en la formación astrofísica de diversos derivados de interés. En el tratamiento espectroscópico se han hecho esfuerzos interesantes, que han aunado teoría y experimento, en el estudio de sistemas relevantes desde el punto de vista atmosférico, como los hidratos de ácido nítrico, o el tratamiento espectroscópico de moléculas no rígidas. No menos interesantes son los estudios de fotoabsorción de radicales o de procesos multifotónicos. Son particularmente abundantes los estudios dedicados a la reactividad específica de sistemas de interés astrofísico o atmosférico, con el objetivo de esclarecer vías de formación de determinados compuestos o de proporcionar mecanismos que permitan identificar las etapas reactivas limitantes de reacciones de interés en esos medios y sobre los que no existía información previa. Así, por ejemplo, se han publicado interesantes estudios sobre la formación o propiedades de compuestos de fósforo, de silico o de azufre o sobre mecanismos de reacción en los que intervienen el ozono, el radical nitrato, el radical OH u otras especies. Finalmente, son también particularmente relevantes los estudios que varios

  11. Électropolymérisation de complexes d'inclusion : vers des fils électriques moléculaires encapsulés

    NASA Astrophysics Data System (ADS)

    Lagrost, C.; Lacroix, J. C.; Aeiyach, S.; Jouini, M.; Chane-Ching, K. I.; Lacaze, P. C.

    1998-06-01

    A new strategy which allows the electrosynthesis of polybithiophene (PBT) from aqueous medium is reported. It uses host/guest complexation, without any covalent bonds being formed prior to the electropolymerization step, hydroxypropyl-β-cyclodextrin (HPβCD) being the host, bithiophene being the guest. IRTF and XPS spectroscopies show i) that PBT/HPβCD films seem similar to that of PBT films achieved in organic media and ii) that cyclodextrins persist in the films despite extensive rinsing. MS- MALDI analyses show that HPβCD are not grafted on the polymer backbone. The abnormal solubility in DMF, DMSO, THF of PT films electrosynthetized in aqueous HPβCD solutions, associated with a high conjugation length (UV vis) and SEC or MS-MALDI analyses suggest that the polymer chains may be partially encapsulated by cyclodextrins. Une stratégie nouvelle utilisant la complexation sans formation de liaisons covalentes entre un monomère hydrophobe, le bithiophène (BT), et une molécule cage soluble dans l'eau, l'hydroxypropyl-β- cyclodextrine (HPβCD) conduit à l'électropolymérisation du polybithiophène (PBT) en milieu aqueux. On obtient des films homogènes, adhérents, d'épaisseur contrôlable et anormalement solubles dans le DMF, le DMSO et le THF. Les spectres IRTF, UV-vis et XPS sont similaires à ceux de polythiophènes synthétisés en milieu organique et indiquent la présence d'HPβCD au sein du film, malgré un rinçage intensif. Les analyses par SEC (Size Exclusion Chromatography) et MS-MALDI (Mass Spectrometry-Matrix Assisted Laser Desorption Ionization) semblent indiquer des masses moléculaires élevées et démontrent l'absence de greffage de HPβCD sur les chaînes polymères. L'ensemble de ces résultats montre une modification des interactions interchaînes et chaînes/solvant et suggère l'obtention de chaînes de PBT partiellement encapsulées.

  12. 44 CFR 10.4 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... development within the sustained carrying capacity of the ecosystem involved; and (4) Enhancing the quality of..., in carrying out its responsibilities, including disaster planning, response and recovery and hazard... means and measures are used to protect, restore, and enhance the quality of the environment, to avoid...

  13. 44 CFR 10.4 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... development within the sustained carrying capacity of the ecosystem involved; and (4) Enhancing the quality of..., in carrying out its responsibilities, including disaster planning, response and recovery and hazard... means and measures are used to protect, restore, and enhance the quality of the environment, to avoid...

  14. 44 CFR 10.4 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... development within the sustained carrying capacity of the ecosystem involved; and (4) Enhancing the quality of..., in carrying out its responsibilities, including disaster planning, response and recovery and hazard... means and measures are used to protect, restore, and enhance the quality of the environment, to avoid...

  15. 44 CFR 10.4 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... development within the sustained carrying capacity of the ecosystem involved; and (4) Enhancing the quality of..., in carrying out its responsibilities, including disaster planning, response and recovery and hazard... means and measures are used to protect, restore, and enhance the quality of the environment, to avoid...

  16. 27 CFR 10.4 - Jurisdictional limits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) General. The regulations in this part apply where: (1) The industry member induces a trade buyer to... representative of a trade buyer in any State and a brewer, importer, or wholesaler of malt beverages inside or... similar transactions between an employee, officer, or representative of a trade buyer in such State and...

  17. 44 CFR 10.4 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., in carrying out its responsibilities, including disaster planning, response and recovery and hazard... development within the sustained carrying capacity of the ecosystem involved; and (4) Enhancing the quality of... considerations, in planning and decisionmaking where there is a potential for significant environmental...

  18. The effect of high-energy radiation on aqueous solution of Acid Red 1 textile dye

    NASA Astrophysics Data System (ADS)

    Földváry, Cs. M.; Wojnárovits, L.

    2007-08-01

    The effect of high-energy radiation on Acid Red 1 (AR1) azo-dye solution was investigated by UV-Vis spectroscopy and chemical oxygen demand (COD) measurements. Doses in the order of 10 kGy cause complete decolouration of the 10 -3-10 -4 mol dm -3 solutions; however, for complete mineralization doses higher by 1-2 order of magnitude are needed. Hydrated electrons and H rad atom are more effective in fading reaction, while the rad OH radicals have higher efficiency in mineralization. The HO 2•/O 2•- radical-radical anion pair is rather inefficient in fading reaction.

  19. Comment on Neiser et al. Assessment of Dextran Antigenicity of Intravenous Iron Preparations with Enzyme-Linked Immunosorbent Assay (ELISA). Int. J. Mol. Sci. 2016, 17, 1185.

    PubMed Central

    Strom, Claes C.; Andreasen, Hans B.

    2017-01-01

    All IV iron complexes carry a risk of potentially fatal allergic type hypersensitivity reactions. The mechanism(s) behind these reactions is unknown but the limited data available suggests that classic IgE mediated allergy is exceedingly rare, if ever occurring. Iron–carbohydrate molecules are complex nano-particles and trying to reduce the risk of serious hypersensitivity to antibody binding of an artificial antibody seems meaningless. A recently published analysis of safety data from randomized clinical trials confirms the method reported by Neiser to be useless to predict reaction risk. In conclusion, the study by Neiser et al. is biased, contains no new information, and has no clinical relevance. We are concerned that the association of the authors with a commercial entity has caused a conflict of interest that biases not only the results, but the entire experimental setup against competitors. (Comment on Neiser et al. Int. J. Mol. Sci. 2016, 17, 1185, doi:10.3390/ijms17071185). PMID:28075402

  20. Crystal structure of an aryl cyclo­hexyl nona­noid, an anti­proliferative mol­ecule isolated from the spice Myristica malabarica

    PubMed Central

    Bauri, Ajoy Kumar; Foro, Sabine; Do, Nhu Quynh Nguyen

    2016-01-01

    The title compound, C21H26O5, an aryl cyclo­hexyl nona­noid {systematic name: 3,5-dihy­droxy-2-[9-(4-hy­droxy­phen­yl)nona­noyl]cyclo­hexa-2,4-dien-1-one}, extracted from the spice plant Myristica malabarica comprises two ring components, a 4-hy­droxy­phenyl moiety and a 3,5-di­hydroxy­cyclo­hexa-2,4-dienone moiety linked by a nona­noyl chain. The mol­ecule has an extended essentially planar conformation stabilized by an intra­molecular hy­droxy O—H⋯Ocarbon­yl hydrogen bond, giving a dihedral angle between the two ring systems of 6.37 (15)°. The C, O and H atoms associated with one of the hy­droxy groups of the cyclo­hexa­dienone component are disordered over two sets of sites with site occupancies of 0.6972 and 0.3028. In the crystal, hy­droxy O—H⋯O hydrogen bonds to carbonyl O-atom acceptors form large centrosymmetric R 2 2(36) cyclic dimers, which are further extended into supra­molecular one-dimensional ribbon structures along [1-11]. PMID:27746930

  1. The certification of a nominal 20 micromol/mol H2S/N2 standard reference material using two independent methods.

    PubMed

    Miller, Walter R; Guenther, Franklin R

    2007-04-01

    To support federal, state and local regulations on the amount of hydrogen sulfide (H(2)S) released into the atmosphere, the National Institute of Standards and Technology (NIST) has certified standard reference material (SRM) 2731 Hydrogen Sulfide in Nitrogen (nominal amount-of-substance fraction 20 micromol/mol H(2)S). Since it was first produced and certified in 1989, NIST has certified four separate lots of this SRM. In each case, the value assignment of the lot concentration was accomplished by comparison to a permeation tube-generated calibration curve. For the certification of the new lot, two independent methods were used to value-assign the concentration. In addition to the permeation tube method, a second method involving the dynamic dilution of a high-concentration gravimetrically prepared primary standard mixture containing H(2)S/N(2) was also used. Agreement between the two methods was 0.10% and the total uncertainty assigned to the lot concentration was 1.35% (relative).

  2. Direct identification of phenolic constituents in Boldo Folium (Peumus boldus Mol.) infusions by high-performance liquid chromatography with diode array detection and electrospray ionization tandem mass spectrometry.

    PubMed

    Simirgiotis, M J; Schmeda-Hirschmann, G

    2010-01-22

    A very simple and direct method was developed for the qualitative analysis of polyphenols in boldo (Peumus boldus Mol., Monimiaceae) leaves infusions by high-performance liquid chromatography with diode array detection (HPLC-DAD) and electrospray ionization tandem mass spectrometry (HPLC-MS(n)). The phenolic constituents identified in infusions of the crude drug Boldo Folium were mainly proanthocyanidins and flavonol glycosides. In the infusions, 41 compounds were detected in male and 43 compounds in female leaf samples, respectively. Nine quercetin glycosides, eight kaempferol derivatives, nine isorhamnetin glycosides, three phenolic acids, one caffeoylquinic acid glycoside and twenty one proanthocyanidins were identified by HPLC-DAD and ESI-MS for the first time in the crude drug. Isorhamnetin glucosyl-di-rhamnoside was the most abundant flavonol glycoside in the male boldo sample, whereas isorhamnetin di-glucosyl-di-rhamnoside was the main phenolic compound in female boldo leaves infusion. The results suggest that the medicinal properties reported for this popular infusion should be attributed not only to the presence of catechin and boldine but also to several phenolic compounds with known antioxidant activity. The HPLC fingerprint obtained can be useful in the authentication of the crude drug Boldo Folium as well as for qualitative analysis and differentiation of plant populations in the tree distribution range.

  3. Estudio teórico de moléculas de interés en Astrofísica: compuestos binarios policarbonados

    NASA Astrophysics Data System (ADS)

    Largo-Cabrerizo, A.

    Se han detectado en el espacio distintos compuestos binarios policarbonados (que se pueden formular como CnX), algunos de ellos con elementos de la primera fila del sistema periódico, pero también existen otros que contienen elementos de la segunda fila, como azufre o silicio. La información experimental sobre estos últimos compuestos es escasa, por lo que los estudios teóricos son especialmente valiosos en este campo. En esta comunicación presentaremos los avances mas recientes que sobre el tema ha realizado nuestro grupo. Incidiremos particularmente en dos aspectos. En primer lugar resumiremos los estudios en los que hemos intentado proporcionar información estructural sobre carburos metálicos formados por sodio, magnesio, aluminio o calcio, que pueda ser de ayuda a la hora de caracterizar estas moléculas en laboratorio como paso previo a su eventual detección en el espacio. Un aspecto importante dentro de este primer apartado es el análisis de las propiedades moleculares en función del tamaño del sistema (cuantificado en el numero de átomos de carbono) con el objeto de intentar sistematizar su estudio. En segundo lugar comentaremos brevemente algunos de los estudios realizados sobre posibles reacciones que pueden ser vías de síntesis de este tipo de compuestos en el medio interestelar.

  4. Certification of NIST standard reference material 2389a, amino acids in 0.1 mol/L HCl--quantification by ID LC-MS/MS.

    PubMed

    Lowenthal, Mark S; Yen, James; Bunk, David M; Phinney, Karen W

    2010-05-01

    An isotope-dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS) measurement procedure was developed to accurately quantify amino acid concentrations in National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 2389a-amino acids in 0.1 mol/L hydrochloric acid. Seventeen amino acids were quantified using selected reaction monitoring on a triple quadrupole mass spectrometer. LC-MS/MS results were compared to gravimetric measurements from the preparation of SRM 2389a-a reference material developed at NIST and intended for use in intra-laboratory calibrations and quality control. Quantitative mass spectrometry results and gravimetric values were statistically combined into NIST-certified mass fraction values with associated uncertainty estimates. Coefficients of variation (CV) for the repeatability of the LC-MS/MS measurements among amino acids ranged from 0.33% to 2.7% with an average CV of 1.2%. Average relative expanded uncertainty of the certified values including Types A and B uncertainties was 3.5%. Mean accuracy of the LC-MS/MS measurements with gravimetric preparation values agreed to within |1.1|% for all amino acids. NIST SRM 2389a will be available for characterization of routine methods for amino acid analysis and serves as a standard for higher-order measurement traceability. This is the first time an ID LC-MS/MS methodology has been applied for quantifying amino acids in a NIST SRM material.

  5. Application de la topologie moléculaire à la prédiction de la viscosité liquide des composés organiques

    NASA Astrophysics Data System (ADS)

    García-Domenech, R.; Villanueva, A.; Gálvez, J.; Gozalbes, R.

    1999-07-01

    Molecular Topology has been applied to search for a mathematical model able to predict liquid viscosity values for an extensive group of organic compounds with C, H, O, N, S and halogenous atoms. The topological descriptors we have used are the connectivity indices from Kier et Hall -up to fourth order-, and the electrotopological indices. Quality of regression equation finally selected has been evaluated by a crossvalidation study. Viscosity of all compounds excepted 1,1,2-trichlorotrifluoro etane is correctly predicted by the model proposed. Nous avons appliqué la topologie moléculaire à la recherche d'un modèle mathématique capable de prédire la viscosité liquide d'un large groupe de composés organiques contenant C, H, O, N, S et des halogènes. Les descripteurs topologiques utilisés pour cette étude des relations quantitatives structure-propiété, R.Q.S.P., sont les indices de connectivité de Kier et Hall -jusqu'à l'ordre quatre- ainsi que les indices atomiques électrotopologiques. La qualité de l'équation de régression multilinéaire obtenue (aussi dite “fonction de connectivité") a été évaluée par une étude de validation croisée. Tous les composés excepté le 1,1,2-trichlorotrifluoréthane s'ajustent au modèle proposé.

  6. Final report on key comparison CCQM-K73: Amount content of H+ in hydrochloric acid (0.1 mol kg-1)

    NASA Astrophysics Data System (ADS)

    Pratt, Kenneth W.; Ortiz-Aparicio, Jose Luis; Matehuala-Sanchez, Francisco Javier; Pawlina, Monika; Kozlowski, Wladyslaw; Borges, Paulo P.; da Silva Junior, Wiler B.; Borinsky, Mónica B.; Hernandez-Mabel Puelles, Ana; Hatamleh, Nadia; Acosta, Osvaldo; Nunes, João; Guiomar Lito, M. J.; Camões, M. Filomena; Filipe, Eduarda; Hwang, Euijin; Lim, Youngran; Bing, Wu; Qian, Wang; Chao, Wei; Hioki, Akiharu; Asakai, Toshiaki; Máriássy, Michal; Hanková, Zuzana; Nagibin, Sergey; Manska, Olexandra; Gavrilkin, Vladimir

    2013-01-01

    This key comparison (KC), CCQM-K73, was performed to demonstrate the capability of the participating National Metrology Institutes (NMIs) to measure the amount content of H+, νH+, in an HCl solution with a nominal νH+ of 0.1 mol kg-1. The comparison was a joint activity of the Electrochemical Working Group (EAWG) and Inorganic Analysis Working Group (IAWG) of the CCQM and was coordinated by NIST (USA) and CENAM (Mexico). The agreement of the results was not commensurate with the claimed uncertainties of the subset of participants that claimed small uncertainties for this determination. A workshop on technical issues relating to the CCQM-K73 measurements was conducted at the joint IAWG-EAWG meeting at the Bureau International des Poids et Mesures (BIPM), Paris (Sèvres) in April 2010. Several possible sources of bias were investigated, but none could explain the observed dispersion among the participants' results. In the absence of a specific cause for the dispersion, the IAWG and EAWG decided to assign a Key Comparison Reference Value, KCRV, and standard uncertainty of the KCRV, uKCRV, based on the DerSimonian-Laird statistical estimator. The uKCRV is dominated by the between-laboratory scatter of results in CCQM-K73. The uncertainty estimates from the participants with the lowest reported uncertainties remain unsupported by this KC. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. Planar CH3NH3PbBr3 hybrid solar cells with 10.4% power conversion efficiency, fabricated by controlled crystallization in the spin-coating process.

    PubMed

    Heo, Jin Hyuck; Song, Dae Ho; Im, Sang Hyuk

    2014-12-23

    A power conversion efficiency of 10.4% is demonstrated in planar CH3 NH3 PbBr3 hybrid solar cells without hysteresis of the J-V curve, by way of controlled crystallization in the spin-coating process. The high efficiency is attributed to the formation of a dense CH3 NH3 PbBr3 thin film by the introduction of HBr solution because the HBr increases the solubility of the CH3 NH3 PbBr3 and forms a thinner CH3 NH3 PbBr3 layer with full surface coverage.

  8. Interaction between magnons and impurity excitations in CoCO3+10-4 Mn2+ and CoF2+4×10-3 Mn2+

    NASA Astrophysics Data System (ADS)

    Naumenko, V. M.

    1981-01-01

    Interaction of host magnons with impurity magnetic excitations in antiferromagnetic crystals CoCO3 and CoF2 containing substitutional impurity amounting to 10-4 and (4±2)×10-3 (by weight) Mn2+ respectively, has been investigated in the wavelength range 0.35 0.8 mm in a magnetic field of up to 20 T. In the CoCO3+10-4 Mn2+ crystal the impurity line was observed to merge with the AFMR line, which is peculiar to incoherent spectrum rearrangement. In the CoF2+4×10-3 Mn2+ crystal the cross splitting of spectrum was revealed as the impurity lower lying Zeeman level approached the AFMR low frequency mode, peculiar to coherent spectrum rearrangement. In both cases the impurity line intensity increases very much as it approaches the spin-wave band of the crystal. The constant of resonance interaction of the impurity excitation with magnons is determined for CoF2+Mn2+ to be m=18 cm-1.

  9. A 45,000-mol-wt protein from unfertilized sea urchin eggs severs actin filaments in a calcium-dependent manner and increases the steady-state concentration of nonfilamentous actin

    PubMed Central

    1984-01-01

    A 45,000-mol-wt protein has been purified from unfertilized sea urchin (Strongylocentrotus purpuratus) eggs. The isolation scheme includes DEAE cellulose ion-exchange chromatography, gel filtration, and hydroxylapatite chromatography. The homogeneity of the isolated protein is greater than 90% by SDS PAGE. The 45,000-mol-wt protein reduces the viscosity of actin filaments in a Ca2+-dependent manner. The free calcium concentration required for the activity of this protein is in the micromolar range. Electron microscopic studies reveal that the formation of short filaments parallels the decrease in viscosity. Energy transfer and sedimentation experiments indicate a net disassembly of actin filaments and an increase in the steady-state nonfilamentous actin concentration in the presence of Ca2+ ions and the 45,000-mol-wt protein. The increase in the steady-state nonfilamentous actin concentration is proportional to the amount of 45,000-mol-wt protein added. The actin molecules disassembled by the addition of the 45,000-mol-wt protein are capable of polymerization. PMID:6540784

  10. Superconducting transition width (ΔT c) characteristics of 25 mol% Zr-added (Gd, Y)Ba2Cu3O7-δ superconductor tapes with high in-field critical current density at 30 K

    NASA Astrophysics Data System (ADS)

    Heydari Gharahcheshmeh, M.; Galstyan, E.; Xu, A.; Kukunuru, J.; Katta, R.; Zhang, Y.; Majkic, G.; Li, X.-F.; Selvamanickam, V.

    2017-01-01

    The superconducting transition width (∆T c) characteristics of REBa2Cu3O7-δ (REBCO and RE = Gd, Y) superconductor tapes with Zr content of 25 mol% with high lift factor (ratio of critical current density (J c) at 30 K, 3 T (B||c) to the J c at 77 K, 0 T) has been determined. In this work, heavily doped (Gd, Y)Ba2Cu3O7-δ superconductor tapes with 25 mol% Zr addition were fabricated by metal organic chemical vapor deposition using a reel-to reel process. The optimal chemical composition range of (Gd, Y)Ba2Cu3O7-δ superconductor tapes with Zr content of 25 mol% to achieve critical current densities above 3.5 MA cm-2 at 77 K in zero applied magnetic field has been determined. A superconducting transition width (∆T c) as narrow as 0.4 K and an onset critical transition temperature (T c-onset) as high as 92 K were obtained in the 25 mol% Zr-added (Gd, Y)BaCuO superconductor tapes. Based on the mapped compositional phase diagram of the ∆Tc and lift factor, ∆T c in the range of 0.7-0.9 K is observed in 25 mol% Zr-added (Gd, Y)BaCuO superconductor tapes with a high lift factor.

  11. Diagnostic moléculaire du complexe Mycobacterium tuberculosis résistant à l'isoniazide et à la rifampicine au Burkina Faso

    PubMed Central

    Désire, Ilboudo; Cyrille, Bisseye; Florencia, Djigma; Souba, Diande; Albert, Yonli; Valerie, Bazie Jean Telesphore; Rebecca, Compaore; Charlemagne, Gnoula; Tamboura, Djibril; Rémy, Moret; Virginio, Pietra; Simplice, Karou Damintoti; Martial, Ouedraogo; Jacques, Simpore

    2015-01-01

    Introduction Cette étude a eu pour objectifs de diagnostiquer la tuberculose pulmonaire par l'examen microscopique et par la PCR des crachats et de déterminer les bases moléculaires de la résistance à la rifampicine et à l'isoniazide. Méthodes Le diagnostic du Complexe Mycobacterium Tuberculosis (CMTB) a été effectué par microscopie après coloration au Ziehl Nielsen et par PCR en temps réel en utilisant le kit d'identification du complexe MTB (Sacace Biotechnologie, Italie). Les résistances à la Rifampicine et à l'Isoniazide ont été étudiées par la technique de la PCR en utilisant le kit MTB résistance 8 (Sacace, Biotechnologie). Résultats Sur les 59 patients diagnostiqués pour la tuberculose pulmonaire, 59,3% étaient positifs en microscopie optique et 44,1% étaient positifs par PCR en Temps réel. Les résistances à la rifampicine (rpoB) et à l'isoniazide (katG et inhA) ont été observées chez 9 patients. La résistance à la rifampicine était due aux mutations (Asp516Val, Ser531Trp, Leu533Pro) et celle à l'isoniazide par les substitutions Ser315Thr du gène katG et C209T du gène inhA. Les multi résistances à la rifampicine et à l'isoniazide ont été observées dans 55,5% des échantillons et concernaient les associations: ropBAsp513Val + inhAC209T et rpoBLeu533Pro + katGSer315Thr. Conclusion La PCR en temps réel qui permet l'identification des allèles mutants rpoB, katG et inhA de M. tuberculosis est un outil de diagnostic épidémiologique de grande importance car elle permet de déterminer le niveau de résistance à la rifampicine et à l'isoniazide. PMID:26491516

  12. Comment on "Synthesis, growth and characterization of a new metal-organic NLO material: Dibromo bis (L-proline) Cd(II)" [J. Mol. Struct. 1080 (2015) 37-43

    NASA Astrophysics Data System (ADS)

    Srinivasan, Bikshandarkoil R.; Naik, Madhavi Z.; Narvekar, Kedar U.

    2015-11-01

    The title paper by Boopathi and Ramasamy reports a study on the crystal growth and characterization of dibromobis(L-proline)cadmium(II) 1. Many points of criticism, concerning the crystal structure of 1 and the magnetic properties of 1, dibromobis(L-proline)zinc(II) 2 (J. Mol. Struc. 1033 (2013) 121-126) and diiodobis(2-aminopyridine)cadmium(II) 3 (J. Mol. Struc. 1042 (2013) 25-31) are described to show that compounds 1 to 3 are not soft magnets but instead diamagnetic solids.

  13. Measurement of the ϕη* distribution of muon pairs with masses between 30 and 500 GeV in 10.4 fb-1 of p p ¯ collisions

    NASA Astrophysics Data System (ADS)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Borysova, M.; Brandt, A.; Brandt, O.; Brock, R.; Bross, A.; Brown, D.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, V. N.; Fauré, A.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Gogota, O.; Golovanov, G.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jeong, M. S.; Jesik, R.; Jiang, P.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kajfasz, E.; Karmanov, D.; Katsanos, I.; Kaur, M.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Lammers, S.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Li, X.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nguyen, H. T.; Nunnemann, T.; Orduna, J.; Osman, N.; Osta, J.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M.-A.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Qin, Y.; Quadt, A.; Quinn, B.; Ratoff, P. N.; Razumov, I.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santos, A. S.; Savage, G.; Savitskyi, M.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Simak, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stoyanova, D. A.; Strauss, M.; Suter, L.; Svoisky, P.; Titov, M.; Tokmenin, V. V.; Tsai, Y.-T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verkheev, A. Y.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Williams, M. R. J.; Wilson, G. W.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yang, S.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yin, H.; Yip, K.; Youn, S. W.; Yu, J. M.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; D0 Collaboration

    2015-04-01

    We present a measurement of the distribution of the variable ϕη* for muon pairs with masses between 30 and 500 GeV, using the complete run II data set collected by the D0 detector at the Fermilab Tevatron proton-antiproton collider. This corresponds to an integrated luminosity of 10.4 fb-1 at √{s }=1.96 TeV . The data are corrected for detector effects and presented in bins of dimuon rapidity and mass. The variable ϕη* probes the same physical effects as the Z /γ* boson transverse momentum, but is less susceptible to the effects of experimental resolution and efficiency. These are the first measurements at any collider of the ϕη* distributions for dilepton masses away from the Z →ℓ+ℓ- boson mass peak. The data are compared to QCD predictions based on the resummation of multiple soft gluons.

  14. Building a conceptual framework for evaluating human-induced hydrological changes during the last millennium in the Mol-Dessel area (NE Belgium)

    NASA Astrophysics Data System (ADS)

    Beerten, Koen; Leterme, Bertrand; Jacques, Diederik

    2014-05-01

    pine plantations, would certainly have amplified the lowering of the groundwater table. In the course of the 20th century, the construction of sand pits and the development of new industries (build area) have probably compensated the gradual deforestation with respect to the local hydrology. The hydrological changes associated with the profound human-induced transformation of the landscape seem to have left traces in soil profiles. Clear discrepancies between the position of the present-day groundwater table and the position of palaeo-wetness indicators can be observed. References Beerten, K., Deforce, K., Mallants, D., 2012. Landscape evolution and changes in soil hydraulic properties at the decadal, centennial and millennial scale: A case study from the Campine area, northern Belgium. Catena, 95, 73-84. Vandersmissen, N., Beerten, K., Deforce, K., Vandenberghe, N., submitted. Late Quaternary (15 ka to present) development of a sandy landscape in the Mol area, Campine region, NE Belgium.

  15. Report of pilot study CCM.P-P1 for international comparison of absolute pressure measurements in gas from 3 × 10-9 Pa to 9 × 10-4 Pa

    NASA Astrophysics Data System (ADS)

    Yoshida, Hajime; Arai, Kenta; Komatsu, Eiichi; Fujii, Kenichi; Bock, Thomas; Jousten, Karl

    2015-01-01

    A bilateral comparison of absolute gas pressure measurements from 3 × 10-9 Pa to 9 × 10-4 Pa was performed between the National Metrology Institute of Japan (NMIJ) and Physikalisch-Technische Bundesanstalt (PTB). It is a pilot study CCM.P-P1 for the next international comparison in this pressure range to test the stability of ultrahigh vacuum gauges (UHV gauges) as transfer standards. Two spinning rotor gauges (SRGs), an axial-symmetric transmission gauge (ATG), and an extractor gauge (EXG) were used as transfer standards. The calibration ratio of one SRG was sufficiently stable, but the other was not. This result indicates that improvements in the transport mechanism for SRG are needed. The two ionization gauges ATG and EXG, on the other hand, were sufficiently stable. Provisional equivalence of the pressures realized by the primary standards at NMIJ and PTB was found. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by CCM-WGS.

  16. Measurement of the φ*η distribution of muon pairs with masses between 30 and 500 GeV in 10.4 fb-1 of pp¯ collisions

    SciTech Connect

    Abazov, Victor Mukhamedovich

    2015-04-06

    We present a measurement of the distribution of the variable φ*η for muon pairs with masses between 30 and 500 GeV, using the complete run II data set collected by the D0 detector at the Fermilab Tevatron proton-antiproton collider. This corresponds to an integrated luminosity of 10.4 fb–1 at √s = 1.96 TeV. The data are corrected for detector effects and presented in bins of dimuon rapidity and mass. The variable φ*η probes the same physical effects as the Z/γ* boson transverse momentum, but is less susceptible to the effects of experimental resolution and efficiency. These are the first measurements at any collider of the φ*η distributions for dilepton masses away from the Z → ℓ+ boson mass peak. As a result, the data are compared to QCD predictions based on the resummation of multiple soft gluons.

  17. Measurement of the φ*η distribution of muon pairs with masses between 30 and 500 GeV in 10.4 fb-1 of pp¯ collisions

    DOE PAGES

    Abazov, Victor Mukhamedovich

    2015-04-06

    We present a measurement of the distribution of the variable φ*η for muon pairs with masses between 30 and 500 GeV, using the complete run II data set collected by the D0 detector at the Fermilab Tevatron proton-antiproton collider. This corresponds to an integrated luminosity of 10.4 fb–1 at √s = 1.96 TeV. The data are corrected for detector effects and presented in bins of dimuon rapidity and mass. The variable φ*η probes the same physical effects as the Z/γ* boson transverse momentum, but is less susceptible to the effects of experimental resolution and efficiency. These are the first measurementsmore » at any collider of the φ*η distributions for dilepton masses away from the Z → ℓ+ℓ– boson mass peak. As a result, the data are compared to QCD predictions based on the resummation of multiple soft gluons.« less

  18. Crystal structure, IR spectroscopic and optical properties of the two (C11N4H10)4·H2O and (C11N4H10)2·H2O compounds

    NASA Astrophysics Data System (ADS)

    Derbel, Amira; Omri, Issam; Allouch, Fatma; Agrebi, Asma; Mhiri, Tahar; Graia, Mohsen

    2015-01-01

    The crystallization of (C11N4H10)2·H2O (I) and (C11N4H10)4·H2O (II) is made by slow evaporation from aqueous solutions. The structures of these compounds have been solved and refined by single-crystal X-ray diffraction data. The compound (I) is centrosymmetric (space group C2/c) with lattice parameters: a = 14.118 (2) Å, b = 7.399 (1) Å, c = 21.982 (3) Å and β = 107.80 (1)°. The compound (II) crystallizes in the same space group (C2/c) with lattice parameters: a = 28.976 (2) Å, b = 7.593 (2) Å, c = 21.724 (2) Å and β = 115.819 (2)°. The cohesion in both structures is provided by two types of bonds: hydrogen bonds Osbnd H⋯N and Nsbnd H⋯O involving water molecules and organic molecules, and Van der Waals bonds for the connection between the organic molecules. The IR spectra shows an enlargement of the band between 3300 and 2800 cm-1, due to the presence of water molecules and the overlap of vibration modes ν (Osbnd H) and ν (Csbnd H, Nsbnd H). The optical band gap is determined to be 4.07 eV by UV-Vis-T90+ absorption spectra, which revealed the nature of insulator.

  19. Effect of boron oxide addition on fibre drawing, mechanical properties and dissolution behaviour of phosphate-based glass fibres with fixed 40, 45 and 50 mol% P2O5

    PubMed Central

    Sharmin, Nusrat; Parsons, Andrew J; Rudd, Chris D

    2014-01-01

    Previous studies investigating manufacture of phosphate-based glass fibres from glasses fixed with P2O5 content less than 50 mol% showed that continuous manufacture without breakage was very difficult. In this study, nine phosphate-based glass formulations from the system P2O5-CaO-Na2O-MgO-B2O3 were prepared with P2O5 contents fixed at 40, 45 and 50 mol%, where Na2O was replaced by 5 and 10 mol% B2O3 and MgO and CaO were fixed to 24 and 16 mol%, respectively. The effect of B2O3 addition on the fibre drawing, fibre mechanical properties and dissolution behaviour was investigated. It was found that addition of 5 and 10 mol% B2O3 enabled successful drawing of continuous fibres from glasses with phosphate (P2O5) contents fixed at 40, 45 and 50 mol%. The mechanical properties of the fibres were found to significantly increase with increasing B2O3 content. The highest tensile strength (1200 ± 130 MPa) was recorded for 45P2O5-16CaO-5Na2O-24MgO-10B2O3 glass fibres. The fibres were annealed, and a comparison of the mechanical properties and mode of degradation of annealed and non-annealed fibres were investigated. A decrease in tensile strength and an increase in tensile modulus were observed for the annealed fibres. An assessment of the change in mechanical properties of both the annealed and non-annealed fibres was performed in phosphate-buffered saline (PBS) at 37℃ for 28 and 60 days, respectively. Initial loss of mechanical properties due to annealing was found to be recovered with degradation. The B2O3-containing glass fibres were found to degrade at a much slower rate as compared to the non-B2O3-containing fibres. Both annealed and non-annealed fibres exhibited a peeling effect of the fibre's outer layer during degradation. PMID:24939962

  20. Effect of boron oxide addition on fibre drawing, mechanical properties and dissolution behaviour of phosphate-based glass fibres with fixed 40, 45 and 50 mol% P2O5.

    PubMed

    Sharmin, Nusrat; Parsons, Andrew J; Rudd, Chris D; Ahmed, Ifty

    2014-11-01

    Previous studies investigating manufacture of phosphate-based glass fibres from glasses fixed with P2O5 content less than 50 mol% showed that continuous manufacture without breakage was very difficult. In this study, nine phosphate-based glass formulations from the system P2O5-CaO-Na2O-MgO-B2O3 were prepared with P2O5 contents fixed at 40, 45 and 50 mol%, where Na2O was replaced by 5 and 10 mol% B2O3 and MgO and CaO were fixed to 24 and 16 mol%, respectively. The effect of B2O3 addition on the fibre drawing, fibre mechanical properties and dissolution behaviour was investigated. It was found that addition of 5 and 10 mol% B2O3 enabled successful drawing of continuous fibres from glasses with phosphate (P2O5) contents fixed at 40, 45 and 50 mol%. The mechanical properties of the fibres were found to significantly increase with increasing B2O3 content. The highest tensile strength (1200 ± 130 MPa) was recorded for 45P2O5-16CaO-5Na2O-24MgO-10B2O3 glass fibres. The fibres were annealed, and a comparison of the mechanical properties and mode of degradation of annealed and non-annealed fibres were investigated. A decrease in tensile strength and an increase in tensile modulus were observed for the annealed fibres. An assessment of the change in mechanical properties of both the annealed and non-annealed fibres was performed in phosphate-buffered saline (PBS) at 37℃ for 28 and 60 days, respectively. Initial loss of mechanical properties due to annealing was found to be recovered with degradation. The B2O3-containing glass fibres were found to degrade at a much slower rate as compared to the non-B2O3-containing fibres. Both annealed and non-annealed fibres exhibited a peeling effect of the fibre's outer layer during degradation.

  1. New data on the presence of celestite into fossil bones from the uppermost Cretaceous Molí del Baró-1 site (Spain) and an alternative hypothesis on its origin

    NASA Astrophysics Data System (ADS)

    Piga, Giampaolo; Marmi, Josep; Galobart, Àngel; Brunetti, Antonio; Lasio, Barbara; Malfatti, Luca; Enzo, Stefano

    2016-05-01

    The Molí del Barò-1 site is located in south-central Pyrenees (Spain) and is dated to about 66.5 Ma (latest Cretaceous), just before the end Cretaceous mass extinction that wiped out most dinosaurs and many other groups of organisms. The site has yielded one of the richest fossil assemblages of the continental upper Maastrichtian from western Europe. A combined investigation by X-ray fluorescence (XRF), Fourier Transform Infrared spectroscopy attenuated total reflectance (FTIR-ATR) and powder X-ray diffraction (XRD), supplemented with the Rietveld analysis, was conducted on twenty-seven fossil bone samples from Molí del Baró-1 vertebrate-bearing fossil site to investigate taphonomy and diagenetic processes in terms of physico-chemical properties. The XRD analysis confirms the unusual presence of celestite and other rare sulphates in the bone structure. Previous explanations of the presence and sometimes abundance of celestite in the fossil bones from this site were based on the supposed total absence of marine water in the original depositionary environment. New geological information suggesting the possibility of marine influence allows formulating an alternative hypothesis focused on the peculiar environment of deposition of Molí del Baró-1 site.

  2. Crystal structure of 6,7-dimeth-oxy-1-(4-nitro-phen-yl)quinolin-4(1H)-one: a mol-ecular scaffold for potential tubulin polymerization inhibitors.

    PubMed

    Lien, Vegard Torp; Olberg, Dag Erlend; Klaveness, Jo; Görbitz, Carl Henrik

    2017-03-01

    The protein tubulin is central for maintaining normal cellular processes, and mol-ecules inter-fering with the tubulin dynamics have potential in the treatment of cancerous diseases. The title compound, C17H14N2O5, was prepared as a lead compound in a project dedicated to the development of therapeutic agents binding to the colchicine binding site on tubulin, thereby inter-fering with the cell division in cancer cells. It holds many of the main structural characteristics for colchicine binding and has the potential for further modification and functionalization. In the title mol-ecule, the benzene ring is inclined to the quinoline ring by 76.10 (8)°. In the crystal, mol-ecules are linked by two pairs of C-H⋯O hydrogen bonds, forming tubular-like arrangements, propagating along the direction of the diagonals of the ab plane, and enclosing R2(2)(26) and R2(2)(16) ring motifs.

  3. Crystal structure of 6,7-dimeth­oxy-1-(4-nitro­phen­yl)quinolin-4(1H)-one: a mol­ecular scaffold for potential tubulin polymerization inhibitors

    PubMed Central

    Lien, Vegard Torp; Olberg, Dag Erlend; Klaveness, Jo; Görbitz, Carl Henrik

    2017-01-01

    The protein tubulin is central for maintaining normal cellular processes, and mol­ecules inter­fering with the tubulin dynamics have potential in the treatment of cancerous diseases. The title compound, C17H14N2O5, was prepared as a lead compound in a project dedicated to the development of therapeutic agents binding to the colchicine binding site on tubulin, thereby inter­fering with the cell division in cancer cells. It holds many of the main structural characteristics for colchicine binding and has the potential for further modification and functionalization. In the title mol­ecule, the benzene ring is inclined to the quinoline ring by 76.10 (8)°. In the crystal, mol­ecules are linked by two pairs of C—H⋯O hydrogen bonds, forming tubular-like arrangements, propagating along the direction of the diagonals of the ab plane, and enclosing R 2 2(26) and R 2 2(16) ring motifs. PMID:28316827

  4. Dust formation and mass loss around intermediate-mass AGB stars with initial metallicity Zini ≤ 10-4 in the early Universe - I. Effect of surface opacity on stellar evolution and the dust-driven wind

    NASA Astrophysics Data System (ADS)

    Tashibu, Shohei; Yasuda, Yuki; Kozasa, Takashi

    2017-04-01

    Dust formation and the resulting mass loss around asymptotic giant branch (AGB) stars with initial metallicity in the range 0 ≤ Zini ≤ 10-4 and initial mass 2 ≤ Mini/M⊙ ≤ 5 are explored by hydrodynamical calculations of the dust-driven wind (DDW) along the AGB evolutionary tracks. We employ the MESA code to simulate the evolution of stars, assuming an empirical mass-loss rate in the post-main-sequence phase and considering three types of low-temperature opacity (scaled-solar, CO-enhanced and CNO-enhanced opacity) to elucidate the effect on stellar evolution and the DDW. We find that the treatment of low-temperature opacity strongly affects dust formation and the resulting DDW; in the carbon-rich AGB phase, the maximum dot{M} of Mini ≥ 3 M⊙ stars with the CO-enhanced opacity is at least one order of magnitude smaller than that with the CNO-enhanced opacity. A wide range of stellar parameters being covered, the necessary condition for driving efficient DDW with dot{M} ≥ 10^{-6} M⊙ yr-1 is expressed as effective temperature Teff ≲ 3850 K and log (δCL/κRM) ≳ 10.43log Teff - 32.33, with the carbon excess δC defined as εC - εO, the Rosseland mean opacity κR in units of cm2 g-1 in the surface layer and the stellar mass (luminosity) M(L) in solar units. The fitting formulae derived for gas and dust mass-loss rates in terms of input stellar parameters could be useful for investigating the dust yield from AGB stars in the early Universe being consistent with stellar evolution calculations.

  5. Estudio comparativo de las moléculas isovalentes de interés atmosférico CF3Cl y CF3Br y sus correspondientes halógenos aislados Cl y Br.

    NASA Astrophysics Data System (ADS)

    Mayor, E.; Velasco, A. M.; Martín, I.; Lavín, C.

    Los estados Rydberg moleculares han suscitado en los últimos años un creciente interés entre los espectroscopistas experimentales, motivado en parte por el desarrollo de nuevas técnicas espectroscópicas capaces de investigar estos estados altamente excitados electrónicamente. Los procesos de fotoabsorción que implican estados Rydberg en los derivados halogenados del metano son de gran importancia, debido a su abundancia en la atmósfera y a sus implicaciones medioambientales. Por ello, la obtención de datos relativos a sus fuerzas de oscilador es de gran interés. En este trabajo se aborda el estudio de dichas propiedades para las moléculas isovalentes CF3Cl y CF3Br. Ambas moléculas presentan idéntica estructura electrónica para el estado fundamental por lo que se espera que sus espectros Rydberg presenten grandes similitudes, en ausencia de perturbaciones. Por ello y dada la escasez de datos relativos a fuerzas de oscilador, hemos establecido la corrección de nuestros resultados en base a las analogías esperadas en las intensidades espectrales correspondientes a transiciones análogas. Por otro lado, Novak y col. [1] han encontrado experimentalmente un marcado carácter atómico en el espectro correspondiente a estas moléculas, siendo muy similar a los de los átomos de Cl y Br. Por ello en el presente trabajo, además de establecer la comparación entre ambas moléculas hemos buscado las similitudes con sus respectivos halógenos. Los cálculos relativos a las especies moleculares se han realizado utilizando la Metodología Molécular de Orbítales de Defecto Cuántico (MQDO) [2], mientras que para el estudio de los átomos de Cl y Br se empleó la versión relativista del método (RQDO) [3].

  6. Solubility enhancement of simvastatin by arginine: thermodynamics, solute-solvent interactions, and spectral analysis.

    PubMed

    Meor Mohd Affandi, M M R; Tripathy, Minaketan; Shah, Syed Adnan Ali; Majeed, A B A

    2016-01-01

    We examined the solubility of simvastatin in water in 0.01 mol·dm(-3), 0.02 mol·dm(-3), 0.04 mol·dm(-3), 0.09 mol·dm(-3), 0.18 mol·dm(-3), 0.36 mol·dm(-3), and 0.73 mol·dm(-3) arginine (ARG) solutions. The investigated drug is termed the solute, whereas ARG the cosolute. Phase solubility studies illustrated a higher extent of solubility enhancement for simvastatin. The aforementioned system was subjected to conductometric and volumetric measurements at temperatures (T) of 298.15 K, 303.15 K, 308.15 K, and 313.15 K to illustrate the thermodynamics involved and related solute-solvent interactions. The conductance values were used to evaluate the limiting molar conductance and association constants. Thermodynamic parameters (ΔG (0), ΔH (0), ΔS (0), and E s) for the association process of the solute in the aqueous solutions of ARG were calculated. Limiting partial molar volumes and expansibilities were evaluated from the density values. These values are discussed in terms of the solute-solvent and solute-cosolute interactions. Further, these systems were analyzed using ultraviolet-visible analysis, Fourier-transform infrared spectroscopy, and (13)C, (1)H, and two-dimensional nuclear overhauser effect spectroscopy nuclear magnetic resonance to complement thermophysical explanation.

  7. Demographical, Clinical, and Psychological Characteristics of Users and Nonusers of an Online Platform for T2DM Patients (e-VitaDM-3/ZODIAC-44)

    PubMed Central

    Roelofsen, Yvonne; van Vugt, Michael; Hendriks, Steven H.; van Hateren, Kornelis J. J.; Groenier, Klaas H.; Snoek, Frank J.; Kleefstra, Nanne; Huijsman, Robbert; Bilo, Henk J. G.

    2016-01-01

    Background. Online platforms offer opportunities for support in changing lifestyle and taking responsibility for one's health, but engaging patients with type 2 diabetes is challenging. Previous studies have shown that patients interested in platforms were more often male, younger, and higher educated. This study aims to investigate differences in clinical and psychological characteristics between users and nonusers of a newly developed platform. Methods. A prospective study started in the Drenthe region of Netherlands. Participants in the study concerning quality of care and quality of life were additionally invited to use the platform. Results. 633 patients were registered after they opted for platform use. Of these patients, 361 (57.0%) never logged on, 184 (29.1%) were labeled “curious” users, and 88 (13.9%) were identified as “active” users. Users had lower HbA1c levels and more often hypertension compared to nonusers, and reported higher quality of life, better well-being, lower diabetes-related distress, and better medication adherence. Discussion. Platform use was associated with more favorable clinical and psychological characteristics relative to nonuse. Those with greater severity of disease, lower mood, and progression of disease used the platform the least. Other approaches need to be developed to reach these patients. Furthermore, improving the platform could also help to reach them. This trial is registered with Clinicaltrials.gov NCT01570140. PMID:26682232

  8. Product rotational angular momentum polarization of H+FCl (v=0-5; j=0, 3, 6, 9) → HF+Cl and HCl+F at Erel=0.5-20 kcal mol(-1).

    PubMed

    Chao Wu, Victor Wei-Keh

    2015-12-01

    The rotational angular momentum polarizations of product molecules of the title reactions on the ground potential energy surface 1 (2)A' of DHTSN [Deskevic et al. J Chem Phys 2006, 124, 224303] have been studied using the quasi-classical trajectory method. Reaction dynamic results of the HF product channel comparing with another channel of HCl with 100,000 trajectories can be accurately resolved. We show the value of the polar p(ϑr) in the range of 0° ≤ ϑr ≤ 180(°), azimuthal p(φr) in the range of 0° ≤ φr ≤ 360(°), and dihedral p(ϑr, φr) in the ranges of 0(°) ≤ ϑr ≤ 180(°) and 0(°) ≤ φr ≤ 360(°); the angular distributions of the product molecules HF and HCl at relative Erel = 0.5, 1, 2, 5, 10, 15, and 20 kcal mol(-1); and four polarization-dependent differential cross sections (PDDCSs) of HF and HCl at Erel = 0.5, 1, 2, 5, 10, and 15 kcal mol(-1). p(φr) distributions at v = 0-5, and j = 0, 3, 6, 9 at every Erel are plotted cylindrically together. The stereo dynamic transformation reaction dependent upon the rovibrational states of the reactant molecule FCl and its relative translational energies around 0.5-5 kcal mol(-1) can be significantly differentiated. Translational and rovibrational enhancements of the title reactions on both early barrier potential energy surfaces have been shown in great detail and clarified. Reaction mechanisms of forward and backward scattering of the product molecules HF and HCl, respectively, have been obtained. Graphical Abstract H + FCl → either HF + Cl (left) or HCl + F (right) is moving along a trajectory on the respective PES.

  9. 1-[(Anthracen-9-yl)carbon-yl]-2,7-di-meth-oxy-naphthalene: a chain-like structure composed of face-to-face type dimeric mol-ecular aggregates.

    PubMed

    Siqingaowa; Tsumuki, Takehiro; Ogata, Kazuki; Yonezawa, Noriyuki; Okamoto, Akiko

    2016-12-01

    The asymmetric unit of the title compound, C27H20O3, contains two independent mol-ecules (A and B). The anthracene ring system is connected to the 2,7-di-meth-oxy-naphthalene core in a twisted manner, with dihedral angles of 86.38 (5) and 79.36 (8)°, respectively, for conformers A and B. In the crystal, face-to-face type dimeric mol-ecular aggregates of each conformer are observed. The dimer of conformer A is formed by two pairs of C-H⋯π inter-actions, and that of conformer B by a pair of (sp(2))C-H⋯O hydrogen bonds. The dimers of conformer A are linked to each other via a π-π stacking inter-action between the anthracene rings to form a chain along the b axis and the chains are aligned along the c axis, forming a sheet structure. The dimers of conformer B are connected to each other via a couple of C-H⋯π inter-actions to form a chain along the b axis. The chains are aligned along the c axis through (sp(2))C-H⋯O=C hydrogen bonds, forming a sheet parallel to the bc plane. The sheets of conformers A and B are alternately stacked along the a axis via two kinds of inter-molecular (sp(2))C-H⋯O=C hydrogen bonds.

  10. Structural analysis of xSrO-(50 - x)CaO-50P2O5 glasses with x=0, 5, or 10 mol% for potential use in a local delivery system for osteomyelitis treatment.

    PubMed

    Comeau, P A; Filiaggi, M J

    2016-01-01

    The introduction of ions into a local delivery matrix is one method of managing degradation and subsequent release of the incorporated therapeutic agents. Of interest in this study was whether we could modify the structural nature of calcium polyphosphate (CPP) glass and the subsequent therapeutic potential of this local delivery matrix with inclusion of strontium (Sr). We found that adding 10 mol% Sr significantly increased the density and chain length of the glass. There was no significant impact of Sr doping on the subsequent loading of vancomycin into the matrix, or the matrix porosity. The noted differences in structural stability, ion release, and vancomycin release between the un-doped CPP matrices and 10 mol% Sr-doped CPP matrices in vitro are likely a result of a decrease in glass disorder upon Sr addition to the glass and preferential retention of Sr over Ca during matrix degradation. This study has provided further evidence that Sr incorporation may serve to both manipulate antibiotic release from the amorphous CPP matrix and provide a potential source of therapeutic ions for enhanced bone regeneration.

  11. Final report on COOMET.QM-S1 (COOMET project no 483/RU/09): Supplementary comparison of primary standard gas mixtures: Nitrogen monoxide in nitrogen (50 µmol/mol)

    NASA Astrophysics Data System (ADS)

    Konopelko, L. A.; Kustikov, Y. A.; Kolobova, A. V.; Shor, N. B.; Efremova, O. V.; Rozhnov, M. S.; Melnyk, D. M.; Kozia, V. G.; Shpilnyi, S. A.; Petryshyn, P. V.; Iakubov, S. E.; Kluchits, A. S.; Ananyin, V. N.; Mironchik, A. M.; Mokhnach, M. V.; Valkova, M.; Stovcik, V.; Walden, J.; Augusto, C. R.; Fioravante, A. L.; Ribeiro, C. C.; Sobrinho, D. C. G.; Oudwater, R. J.; da Cunha, V. S.

    2014-01-01

    Nitrogen monoxide is one of the main contaminants present in the atmospheric air due to emissions of vehicles and power stations. Taking into account the positive experience of VNIIM in the pilot study CCQM-P73 (Nitrogen monoxide gas standards, 30 µmol/mol to 70 µmol/mol), a COOMET project (No 483/RU/09) on the subject was decided and registered in the KCDB as supplementary comparison COOMET.QM-S1. This involved six National Metrology Institutes, aiming to consolidate or support their Calibration and Measurement Capabilities in this field. It was found that most of the results were consistent with the reference (gravimetric) values, with observed differences not exceeding ±1.3% and not exceeding either the appropriate assigned expanded uncertainties. There was, however, one exception: the INMETRO difference from the reference value is slightly higher than the expended uncertainty. The mixtures prepared for this exercise were found to be stable during about one year within the uncertainty of the measurements. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by COOMET, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  12. Translational, vibrational, rotational enhancements and alignments of reactions H + ClF (v = 0-5, j = 0,3,6,9) → HCl + F and HF + Cl, at Erel = 0.5-20 kcal/mol

    NASA Astrophysics Data System (ADS)

    Victor Wei-Keh, Chao(Wu

    2013-10-01

    Quasi-classical trajectory calculations of the title reactions H + ClF (v = 0-5, j = 0,3,6,9) → HCl + F and H + ClF (v = 0-5, j = 0,3,6,9) → HF + Cl at Erel = 0.5 kcal/mol-20 kcal/mol on ground potential energy surface DHTSN of 1 2A' [M. P. Deskevich, M. Y. Hayes, K. Takahashi, R. T. Skodje and D. J. Nesbitt, J. Chem. Phys. 124, 224303 (2006)] are performed. Potential energy surfaces derived from DHTSN for the title reactions are obtained, and compared with that of DHTSN for the reaction F + HCl → HF + Cl. Both potential energy surfaces have an early barrier pattern. Integral cross sections and alignments of product molecules HCl and HF dependent on the internal energy states v and j of reactant molecule ClF are obtained and compared. Translational, vibrational, and rotational energy specific translational enhancements of the reactant molecule ClF of the title reactions are found. Reaction mechanisms of the title reactions according to the respective potential energy contours are further found and explained. Reasons of simultaneous translational and vibrational enhancements are clarified.

  13. Electrical and mechanical properties of ZrO{sub 2}(2 mol% Y{sub 2}O{sub 3})/WSi{sub 2} composites and their laminated materials

    SciTech Connect

    Muraoka, Yoshiyuki; Kawahara, Satoshi; Hirota, Ken; Yamaguchi, Osamu

    1996-04-01

    Well-densified composites with the compositions ZrO{sub 2}(2Y)/WSi{sub 2} = 60/40 and 80/20 mol% have been fabricated by hot isostatic pressing for 2 h at 1,500 C and 196 MPa. Electric resistivities ({rho}) of the two composites are very different; the former and latter composites correspond to metallic and insulating materials, respectively. The properties are strongly dependent on the textures. Laminated materials with the ZrO{sub 2}(2Y)/WSi{sub 2} = (60/40)/(80/20)/(60/40) mol% have been prepared by the same technique. Overall electric resistivities in directions perpendicular and parallel to the interfaces have been determined to be {rho}{sub {perpendicular}} {approx} 1 {times} 10{sup 11} {Omega} {center_dot} cm and {rho}{sub {parallel}} {approx} 1 {times} 10{sup {minus}4} {Omega} {center_dot} cm, respectively. Residual stress as much as {approx} 150 MPa is induced in the interfaces. The fracture toughness (K{sub Ic}) is greatly affected by the residual stress.

  14. An x-ray photoemission electron microscopy study of the formation of Ti-Al phases in 4 mol% TiCl3 catalyzed NaAlH4 during high energy ball milling

    NASA Astrophysics Data System (ADS)

    Dobbins, Tabbetha; Abrecht, Mike; Uprety, Youaraj; Moore, Kristan

    2009-05-01

    This study reports reaction pathways to form TiAlx metallic complexes during the high energy ball milling of 4 mol% TiCl3 with NaAlH4 powders determined using local structure analysis of Tix+ and Alx+ species. Using x-ray photoemission electron microscopy (XPEEM) and x-ray diffraction (XRD), the oxidation state of Alx+ and Tix+ and the crystalline compounds existing in equilibrium with NaAlH4 were tracked for samples milled for times of 0 (i.e. mixing), 5, and 25 min. XPEEM analysis of the Al K edge after 5 min of milling reveals that Al remains in the 3+ oxidation state (i.e. in NaAlH4) around Ti0-rich regions of the sample. After 25 min of high energy milling, Ti0 has reacted with Al3+ (in nearby NaAlH4) to form TiAlx complexes. This study reports the pathway for TiAlx complex formation during milling of 4 mol% TiCl3 catalyzed NaAlH4 to be as follows: (1) Ti3+ reduces to Ti0 (with Al3+ near Ti0 regions) and (2) Ti0 reacts with Al3+ in NaAlH4 to form TiAlx complexes.

  15. Interaction of copper(II) complex of compartmental Schiff base ligand N,N'-bis(3-hydroxysalicylidene)ethylenediamine with bovine serum albumin.

    PubMed

    Boghaei, Davar M; Farvid, Shokouh S; Gharagozlou, Mehrnaz

    2007-03-01

    Circular dichroism (CD) spectroscopy, cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the interaction between copper(II) complex of compartmental Schiff base ligand (L), N,N'-bis(3-hydroxysalicylidene)ethylenediamine, and bovine serum albumin (BSA) in 0.1 mol dm(-3) phosphate buffer solution adjusted to physiological pH 7.0 containing 20% (w/w) dimethylsulfoxide at room temperature. CD spectra show that the interaction of the copper(II) complex with BSA leads to changes in the alpha-helical content of BSA and therefore changes in secondary structure of the protein with the slight red shift (2 nm) in CD spectra. From the voltammetric data, i.e. changes in limiting current with addition of BSA, the binding constant (K) of the interaction of copper(II) complex with BSA was found to be 1.96 x 10(4)dm(3)mol(-1). From the shifts in potential with the addition of BSA, the equilibrium constant ratio (K(2)/K(1)) for the binding of the oxidized Cu(II)L (K(1)) and reduced Cu(I)L (K(2)) species to BSA was found to be 3.77, which shows that the reduced form Cu(I)L is bound more strongly to BSA than the oxidized form Cu(II)L.

  16. Hydrolysis of ionized deoxycholic acid in the aqueous phase and rate analysis for transfer of neutralized deoxycholic acid into the benzene phase across the benzene/water interface.

    PubMed

    Ohno, Ryo; Nakamura, Shohei; Moroi, Yoshikiyo; Isoda-Yamashita, Teruyo

    2008-11-13

    Sodium deoxycholate in water dissociates into sodium cation and deoxycholate anion in the aqueous phase, and then, the latter anions partially hydrolyze to form deionized deoxycholic acids. The acids move into the benzene phase, when liquid benzene is placed upon the aqueous phase, and finally the partition equilibrium is reached. The above processes were traced by pH change in the aqueous phase by a pH meter or the change in [OH-] with time, from which the rate for transfer of neutralized acid to the organic phase was analyzed. From the trace, the rate constants for hydrolysis of acid anion ( kf), neutralization of acid ( kb), transfer of neutralized acid from the aqueous phase to the organic phase ( kin*), and its back-transfer from the organic phase to the aqueous phase ( kut*) were evaluated; kf = 2.18 x 10 (-4) mol (-1) dm (3) min (-1), kb = 1.24 x 10 (5) mol (-1) dm (3) min (-1), kin* = 4.06 x 10 (-1) min (-1) cm (-2), and kout*) = 8.00 x 10 (-2) min (-1) cm (-2). The above values are supported by the partition constant of deoxycholic acid between the benzene phase and the aqueous phase.

  17. Development of a time-resolved attenuated total reflectance spectrometer in far-ultraviolet region

    NASA Astrophysics Data System (ADS)

    Morisawa, Yusuke; Higashi, Noboru; Takaba, Kyoko; Kariyama, Naomi; Goto, Takeyoshi; Ikehata, Akifumi; Ozaki, Yukihiro

    2012-07-01

    A far-ultraviolet transient absorption spectrometer based on time-resolved attenuated total reflectance (ATR) has been developed and tested for aqueous solutions of phenol and tryptophan in the region 170-185 nm. In this region, a stable tunable laser was not available, and therefore, white light from a laser-driven Xe lamp source was used. The time resolution, which was determined by the time response of a continuous light detector, was 40 ns. A new ATR cell where a sample liquid is exchanged continuously by a flow system was designed to reduce efficiently the stray light from the excitation light. We have tested the performance of the instrument by using aqueous solutions of phenol and tryptophan, whose photochemistry is already well known. Phenol and tryptophan have very strong absorptions due to a π-π* transition near 180 nm. Even for dilute solutions (10-3 mol dm-3), we could observe decreases in their concentrations due to photochemistry that occurred upon their irradiation with a fourth harmonic generation laser pulse produced by an Nd:YAG laser. The sensitivity of the spectrometer was about 10-4 abs, which corresponded to a concentration variation of 10-3 mol dm-3 for phenol and tryptophan.

  18. 5'-Guanosine monophosphate mediated biocompatible porous hydrogel of β-FeOOH-viscoelastic behavior, loading, and release capabilities of freeze-dried gel.

    PubMed

    Kumar, Anil; Gupta, Sudhir Kumar

    2014-09-04

    The present manuscript reports the characterization, optimization of rheological properties, and loading and release capabilities of 5'-GMP mediated β-FeOOH hydrogel. Circular dichroism (CD) analysis indicates it to contain mainly the left-handed helix similar to that of Z-DNA. The highest viscosity (>300 cP) corresponds to the sample containing 2.5 × 10(-3) mol dm(-3) of 5'-GMP (SP2H). Field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM) studies indicate the freeze-dried (FD) SP2H to be porous in nature, which is also supported by its high Brunauer-Emmett-Teller (BET) surface area of 226 m(2)/g as compared to that of SP3H (75 m(2)/g). Selected area electron diffraction (SAED) analysis and Raman spectroscopy show it to contain β-FeOOH phase. The FD SP2H exhibits the high swelling ratio (326%) and loading capacity for methylene blue (MB) dye. It displays a controlled and efficient release (>90%) for optimized [MB] (2.5 × 10(-4) mol dm(-3)) in 48 h. The low toxicity of as synthesized FD SP2H nanostructures against MDA-MB-231 (breast cancer cells) up to 100 μg/mL suggests its biocompatible nature. The high porosity, surface area, % swelling, and loading and release performance of the hydrogel indicate its potential for drug delivery and other biological applications.

  19. Single crystals of Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-35 mol% PbTiO from polycrystalline precursors

    SciTech Connect

    Li, T.; Scotch, A.M.; Chan, H.M.; Harmer, M.P.; Park, S.E.; Shrout, T.R.; Michael, J.R.

    1998-01-01

    A potentially more cost-efficient method of growing single-crystal relaxor-based ferroelectric materials has been investigated. Seed single crystals of Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3} (PMN)-35 mol% PbTiO{sub 3} (PT) were embedded within polycrystalline powders and annealed at temperatures from 900--1,200 C. The boundary of the single crystal migrated through the polycrystal matrix under the influence of grain boundary curvature; growth distances of several millimeters were observed, verifying the feasibility of the approach. The grown single crystals exhibited macroscopic cubic growth morphologies with (100) faces. Strain levels as high as 0.68% under an electric field of 30 kV/cm were observed in initial measurements.

  20. Thermo-optic dispersion formula for the ordinary wave in 5 mol% MgO doped LiNbO3 and its application to temperature insensitive second-harmonic generation

    NASA Astrophysics Data System (ADS)

    Umemura, Nobuhiro; Matsuda, Daisuke

    2016-05-01

    We report the high accuracy thermo-optic dispersion formula for the ordinary wave of 5 mol% MgO doped congruent LiNbO3 (MgO:LiNbO3), which reproduces well our experimental data for the temperature-dependent birefringent phase-matching (BPM) and quasi-phase-matching (QPM) conditions with the oo-e, oo-o, and oe-o interactions in the 0.41-3.7 μm range. In addition, we found the temperature insensitive quasi-phase-matched second-harmonic generation (QPM/SHG) points exist in periodically poled MgO:LiNbO3 (MgO:PPLN) with the oo-o and oe-o interactions for the first time.

  1. Study of the interactions of molten sodium nitrate-potassium nitrate 50 mol % mixture with water vapor and carbon dioxide in air. Final report, June 2, 1980-June 30, 1981

    SciTech Connect

    White, S.H.; Twardoch, U.M.

    1981-09-01

    The interactions of aerial components such as water, carbon dioxide, and oxygen with the binary 50 mol % mixture of sodium nitrate and potassium nitrate have been studied in the temperature range 300 to 600/sup 0/C using electrochemical methods. In addition, the behavior of nitrite ions in this melt was investigated electrochemically. By judicious choice of techniques, in situ electroanalysis was possible and the necessary relevant data to accomplish this is presented, as well as insight into the corresponding electrochemical mechanisms associated with the electroactive species. The influence of each atmospheric component was examined separately. At temperatures above 300/sup 0/C, nitrite ions are found to accumulate due to thermal decomposition of the nitrate. Water is highly soluble in the salt mixture, but no hydrolytic reactions were observed. Two methods of in situ analysis for water are described. Pure carbon dioxide is found to attack the melt at all temperatures above 250/sup 0/C producing carbonate. (LEW)

  2. 6-Isopropyl-3-phenyl-5-(p-tol­yloxy)-3H-1,2,3-triazolo[4,5-d]pyrimidin-7(6H)-one: whole-mol­ecule disorder

    PubMed Central

    Zeng, Xiao-Hua; Deng, Shou-Heng; Chen, Ping; Wang, Hong-Mei; Gao, Hai-Tao

    2009-01-01

    The title compound, C20H19N5O2, exhibits whole-mol­ecule disorder the refined ratios of the two components being 0.57 (2):0.43 (2). In the major component, the essentially planar [maximum deviation 0.033 (17) Å] fused pyrimidine and triazole ring system forms a dihedral angle of 10.5 (3)° with the phenyl ring, while in the minor component of disorder this angle is 27.5 (5)°. The crystal structure is stabilized by π–π stacking inter­actions between symmetry-related triazole and pyrimidine rings, with centroid–centroid distances of 3.594 (10) Å. PMID:21578267

  3. Different cation-protonation patterns in mol­ecular salts of unsymmetrical dimethyhydrazine: C2H9N2·Br and C2H9N2·H2PO3

    PubMed Central

    Katinaitė, Judita; Harrison, William T. A.

    2016-01-01

    We describe the syntheses and crystal structures of two mol­ecular salts containing the 1,1-di­methyl­hydrazinium cation, namely 1,1-di­methyl­hydrazin-1-ium bromide, C2H9N2 +·Br−, (I), and 2,2-di­methyl­hydrazin-1-ium di­hydrogen phosphite, C2H9N2 +·H2PO3 −, (II). In (I), the cation is protonated at the methyl­ated N atom and N—H⋯Br hydrogen bonds generate [010] chains in the crystal. In (II), the cation is protonated at the terminal N atom and cation-to-anion N—H⋯O and anion-to-anion O—H⋯O hydrogen bonds generate (001) sheets. PMID:27536415

  4. Oxygen isotope systematics in the aragonite-CO2-H2O-NaCl system up to 0.7 mol/kg ionic strength at 25 °C

    USGS Publications Warehouse

    Kim, Sang-Tae; Gebbinck, Christa Klein; Mucci, Alfonso; Coplen, Tyler B.

    2014-01-01

    To investigate the oxygen isotope systematics in the aragonite-CO2-H2O-NaCl system, witherite (BaCO3) was precipitated quasi-instantaneously and quantitatively from Na-Cl-Ba-CO2 solutions of seawater-like ionic strength (I = 0.7 mol/kg) at two pH values (~7.9 and ~10.6) at 25 °C. The oxygen isotope composition of the witherite and the dissolved inorganic carbon speciation in the starting solution were used to estimate the oxygen isotope fractionations between HCO3¯ and H2O as well as between CO3 2 and H2O. Given the analytical error on the oxygen isotope composition of the witherite and uncertainties of the parent solution pH and speciation, oxygen isotope fractionation between NaHCO3° and HCO3¯, as well as between NaCO3¯ and CO3 2, is negligible under the experimental conditions investigated. The influence of dissolved NaCl concentration on the oxygen isotope fractionation in the aragonite-CO2-H2O-NaCl system also was investigated at 25 °C. Aragonite was precipitated from Na-Cl-Ca-Mg-(B)-CO2 solutions of seawater-like ionic strength using passive CO2 degassing or constant addition methods. Based upon our new experimental observations and published experimental data from lower ionic strength solutions by Kim et al. (2007b), the equilibrium aragonite-water oxygen isotope fractionation factor is independent of the ionic strength of the parent solution up to 0.7 mol/kg. Hence, our study also suggests that the aragonite precipitation mechanism is not affected by the presence of sodium and chloride ions in the parent solution over the range of concentrations investigated.

  5. 1-[(Anthracen-9-yl)carbon­yl]-2,7-di­meth­oxy­naphthalene: a chain-like structure composed of face-to-face type dimeric mol­ecular aggregates

    PubMed Central

    Siqingaowa; Tsumuki, Takehiro; Ogata, Kazuki; Yonezawa, Noriyuki; Okamoto, Akiko

    2016-01-01

    The asymmetric unit of the title compound, C27H20O3, contains two independent mol­ecules (A and B). The anthracene ring system is connected to the 2,7-di­meth­oxy­naphthalene core in a twisted manner, with dihedral angles of 86.38 (5) and 79.36 (8)°, respectively, for conformers A and B. In the crystal, face-to-face type dimeric mol­ecular aggregates of each conformer are observed. The dimer of conformer A is formed by two pairs of C—H⋯π inter­actions, and that of conformer B by a pair of (sp 2)C—H⋯O hydrogen bonds. The dimers of conformer A are linked to each other via a π–π stacking inter­action between the anthracene rings to form a chain along the b axis and the chains are aligned along the c axis, forming a sheet structure. The dimers of conformer B are connected to each other via a couple of C—H⋯π inter­actions to form a chain along the b axis. The chains are aligned along the c axis through (sp 2)C—H⋯O=C hydrogen bonds, forming a sheet parallel to the bc plane. The sheets of conformers A and B are alternately stacked along the a axis via two kinds of inter­molecular (sp 2)C—H⋯O=C hydrogen bonds. PMID:27980839

  6. Contribution of seismic processing to put up the scaffolding for the 3-dimensional study of deep sedimentary basins: the fundaments of trans-national 3D modelling in the project GeoMol

    NASA Astrophysics Data System (ADS)

    Capar, Laure

    2013-04-01

    Within the framework of the transnational project GeoMol geophysical and geological information on the entire Molasse Basin and on the Po Basin are gathered to build consistent cross-border 3D geological models based on borehole evidence and seismic data. Benefiting from important progress in seismic processing, these new models will provide some answers to various questions regarding the usage of subsurface resources, as there are geothermal energy, CO2 and gas storage, oil and gas production, and support decisions-making to national and local administrations as well as to industries. More than 28 000 km of 2D seismic lines are compiled reprocessed and harmonized. This work faces various problems like the vertical drop of more than 700 meters between West and East of the Molasse Basin and to al lesser extent in the Po Plain, the heterogeneities of the substratum, the large disparities between the period and parameters of seismic acquisition, and depending of their availability, the use of two types of seismic data, raw and processed seismic data. The main challenge is to harmonize all lines at the same reference level, amplitude and step of signal processing from France to Austria, spanning more than 1000 km, to avoid misfits at crossing points between seismic lines and artifacts at the country borders, facilitating the interpretation of the various geological layers in the Molasse Basin and Po Basin. A generalized stratigraphic column for the two basins is set up, representing all geological layers relevant to subsurface usage. This stratigraphy constitutes the harmonized framework for seismic reprocessing. In general, processed seismic data is available on paper at stack stage and the mandatory information to take these seismic lines to the final stage of processing, the migration step, are datum plane and replacement velocity. However several datum planes and replacement velocities were used during previous processing projects. Our processing sequence is to

  7. Formation of studtite during the oxidative dissolution of UO2 by hydrogen peroxide: a SFM study.

    PubMed

    Clarens, F; de Pablo, J; Díez-Pérez, I; Casas, I; Giménez, J; Rovira, M

    2004-12-15

    Understanding the formation of alteration phases on the surface of spent nuclear fuel, such as those observed during leaching experiments, is necessary in order to predict the concentration of radionuclides in the near-field of a final repository. Hydrogen peroxide has been identified as one of the oxidants formed by the radiolysis of water in the presence of spent nuclear fuel; especially due to alpha activity. The presence of this species in solution can contribute to the formation of uranium peroxide secondary phases. In this work, we have studied the oxidative dissolution of synthetic UO2 disks in hydrogen peroxide solutions of two different concentrations (5 x 10(-4) and 5 x 10(-6) mol dm(-3)), both at pH 5.8 +/- 0.1. The solid surface evolution of the disks has been followed by means of ex-situ scanning force microscope (SFM) measurements, and uranium concentration in solution has been determined by inductively coupled plasma mass spectrometry. During the first stage of the experiment, SFM images indicate that only UO2 dissolution is occurring. After 142 h, a secondary phase is observed on the surface of the solid at 5 x 10(-4) mol dm(-3) hydrogen peroxide concentration. This secondary phase has been identified by X-ray diffraction as studtite (UO4 x 4H2O). From the analysis of SFM topographic profiles at different elapsed times, a precipitation rate for the studtite has been estimated to be in the range of (8-32) x 10(-10) mol m(-2) s(-1).

  8. Multi-approach mapping to help spatial planning and management of the kelp species L. digitata and L. hyperborea: Case study of the Molène Archipelago, Brittany

    NASA Astrophysics Data System (ADS)

    Bajjouk, Touria; Rochette, Sébastien; Laurans, Martial; Ehrhold, Axel; Hamdi, Anouar; Le Niliot, Philippe

    2015-06-01

    The Molène Archipelago in Brittany (France) hosts one of the largest kelp forests in Europe. Beyond their recognized ecological importance as an essential habitat and food for a variety of marine species, kelp also contributes towards regional economies by means of the alginate industry. Thousands of tons of kelp are collected each year for the needs of the chemical and food industries. Kelp harvesting in Brittany mainly concerns two species, Laminaria digitata (59,000 t) and Laminaria hyperborea (24,000 t), that, together, represent approximately 95% of the national landings. Estimating the available standing stock and its distribution is a clear need for providing appropriate and sustainable management measures. Prior to estimating the spatial distribution of biomasses, we produced a detailed seabed topography map with accurate hard substrate delineation thanks to surveys and appropriate processing of airborne optical and acoustic imaging. Habitat suitability models of presence-absence and biomass were then developed for each species by relating in situ observations from underwater video and sampling to the many biotic and abiotic factors that may govern kelp species distribution. Our statistical approach combining generalized additive models (GAM) in a delta approach also provided spatial uncertainty associated with each prediction to help management decisions. This study confirmed that the adopted strategy, based on an integrated approach, enhanced knowledge on kelp biomass distributions in the Molène Archipelago and provided a promising direct link between research and management. Indeed, the high resolution topography and hard substrate maps produced for the study greatly improved knowledge on the sea bottom of the area. This was also of major importance for an accurate mapping of kelp distribution. The quality of the habitat suitability models was verified with fishing effort data (RECOPESCA program) and confirmed by local managers and kelp harvesters

  9. Silicate speciation in H2O-Na2O-SiO2 fluids from 3 to 40 mol% SiO2, to 600 °C and 2 GPa

    NASA Astrophysics Data System (ADS)

    Steele-MacInnis, Matthew; Schmidt, Christian

    2014-07-01

    The silicate speciation in H2O-Na2O-SiO2 fluids was studied in situ up to 600 °C and 2.0 GPa using Raman spectroscopy and a Bassett-type hydrothermal diamond-anvil cell. Fluid compositions ranged from 3 to 40 mol% SiO2, with various Na/Si ratios. The main trends observed in Raman spectra of fluids with increasing SiO2 concentration include (1) decrease in the intensity of the ∼770 cm-1 band (monomer, Q0, symmetric stretch); (2) increase in the intensity of the ∼1050 cm-1 band (bridging oxygen Si-O-Si antisymmetric stretch) and the bands at ∼450-600 cm-1 (bridging oxygen Si-O-Si bending modes); and (3) increase in spectral contributions at ∼800-1000 cm-1 from stretching vibrations of Q1, Q2 and Q3 species. These trends are interpreted to represent decrease in the proportion of Q0 monomers, and increase in the proportions of Q1 and Q2 (±Q3) species, with increasing silicate concentration in the fluid up to 40 mol% SiO2. Raman spectra in the range of tetrahedral Si-O stretching vibrations (700-1200 cm-1) exhibit little discernable difference with changing Na/Si ratio, when compared at constant molar concentration of SiO2. Particularly at lower Na/Si ratio, increasing silicate concentration also results in increasing relative intensity of the Raman signal of O-H stretching vibrations at about 3300 cm-1, suggesting increased intermolecular hydrogen bonding between H2O molecules and/or oxygen atoms belonging to silicate species. These results suggest that silicate in hydrous fluids in the deep Earth remains occurs predominately as partly polymerized, Q1 and Q2 species up to high silicate concentrations, providing an opportune medium for mobilizing high field-strength and other elements in the lithosphere.

  10. Étude par détection de photons des processus électroniques au sein d'une jonction tunnel dans un milieu moléculaire

    NASA Astrophysics Data System (ADS)

    Perronet, K.

    2005-03-01

    Analysis of the luminescence induced by a STM (scanning tunneling microscope) permits to get insights into the electronic processes taking place in a single nanoscopic tunnel junction. We studied a Au(111)/Au junction under vacuum (UHV) and immersed in a molecular medium. The study under UHV reveals the influence of spatial variations of surface local density of states (LDOS) on the luminescence. The emission at the solid-liquid interface is characterized and the role played by the dielectric function is shown. Time correlations between the emitted single photons are then studied. Depending on the liquid immersing the junction, a photon bunching can occur. We link this bunching with structural changes of the junction induced by the presence of a diffusing molecule. If the HOMO LUMO gap of the molecule is small enough, resonant tunnelling paths exist and tunnelling-electron bunching occurs. Finally, the influence of a self-assembled monolayer on the substrate is investigated. Boundings between triphenylene derivatives and Au(111) are too weak, but with chemisorbed alcanethiols, molecular resolution is reached both on the STM image and on the photon map. We show that the contrast on photon map comes from the modulation of the LDOS spatial extension into the barrier due to the S Au bond. The elaboration of organic multilayers is considered as a route for observing the electroluminescence of a single molecule, isolated from the substrate by thiols and to study correlations of electronic origin. We have already optically characterised such a layer using C{60}. La luminescence induite par STM (microscopie à effet tunnel) est une source d'informations d'une grande richesse sur les processus électroniques au sein d'un objet nanoscopique individuel. Nous nous sommes intéressés à une jonction Au/Au(111) sous vide puis dans un milieu moléculaire. L'étude sous vide a permis de montrer l'influence des variations spatiales des densités d'états de la surface. L

  11. Application of extraction chromatography to the separation of thorium and uranium dissolved in a solution of high salt concentration.

    PubMed

    Fujiwara, Asako; Kameo, Yutaka; Hoshi, Akiko; Haraga, Tomoko; Nakashima, Mikio

    2007-01-26

    Extraction chromatography with commercially available UTEVA resin (for uranium and tetravalent actinide) was applied for the separation of Th and U from control solutions prepared from a multi-element control solution and from sample solutions of solidified simulated waste. Thorium and U in control solutions with 1-5mol/dm(3) HNO(3) were extracted with UTEVA resin and recovered with a solution containing 0.1mol/dm(3) HNO(3) and 0.05mol/dm(3) oxalic acid to be separated from the other metallic elements. Extraction behavior of U in the sample solutions was similar to that in the control solutions, but extraction of Th was dependent on the concentration of HNO(3). Thorium was extracted from 5mol/dm(3) HNO(3) sample solutions but not from 1mol/dm(3) HNO(3) sample solutions. We conjecture that thorium fluoride formation interferes with extraction of Th. Addition of Al(NO(3))(3) and Fe(NO(3))(3), which have higher stability constant with fluoride ion than Th, does improve extractability of Th from 1mol/dm(3) HNO(3) sample solution.

  12. Pulse radiolysis study of ion-species effects on the solvated electron in alkylammonium ionic liquids

    NASA Astrophysics Data System (ADS)

    Kondoh, Takafumi; Asano, Akira; Yang, Jinfeng; Norizawa, Kimihiro; Takahashi, Kenji; Taguchi, Mitsumasa; Nagaishi, Ryuji; Katoh, Ryuzi; Yoshida, Yoichi

    2009-12-01

    The spectra and kinetic behavior of solvated electrons (e sol-) in alkyl ammonium ionic liquids (ILs), i.e. N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide (DEMMA-TFSI), N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium tetrafluoroborate (DEMMA-BF 4), N,N,N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)imide (TMPA-TFSI), N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (PP13-TFSI), N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (P13-TFSI), and N-methyl-N-butylpyrrolidinium bis(trifluoromethanesulfonyl)imide (P14-TFSI) were investigated by the pulse radiolysis method. The e sol- in each of the ammonium ILs has an absorption peak at 1100 nm, with molar absorption coefficients of 1.5-2.3×10 4 dm 3 mol -1 cm -1. The e sol- decayed by first order with a rate constant of 1.4-6.4×10 6 s -1. The reaction rate constant of the solvated electron with pyrene (Py) was 1.5-3.5×10 8 dm 3 mol -1 s -1 in the various ILs. These values were about one order of magnitude higher than the diffusion-controlled limits calculated from measured viscosities. The radiolytic yields ( G-value) of the e sol- were 0.8-1.7×10 -7 mol J -1. The formation rate constant of e sol- in DEMMA-TFSI was 3.9×10 10 s -1. The dry electron (e dry-) in DEMMA-TFSI reacts with Py with a rate constant of 7.9×10 11 dm 3 mol -1 s -1, three orders of magnitude higher than that of the e sol- reactions. The G-value of the e sol- in the picosecond time region is 1.2×10 -7 mol J -1. The capture of e dry- by scavengers was found to be very fast in ILs.

  13. Phase relations in a barium-rich high-temperature region (25-45 mol% CuO, 900-1100 deg. C) of the BaO-CuO{sub x} system

    SciTech Connect

    Klinkova, L.A.; Nikolaichik, V.I.; Barkovskii, N.V.; Fedotov, V.K.

    2011-07-15

    The phase relations have been studied in the BaO-CuO{sub x} system in the range of 25.0-45.0 mol% CuO at 900-1100 deg. C at P(O{sub 2})=21 kPa (air) by visual polythermal analysis (VPA), powder X-ray diffraction (XRD), electron diffraction (ED) with simultaneous energy-dispersive X-ray (EDX) elemental analysis in a transmission electron microscope (TEM), and iodometric chemical analysis. The discrete deviations 2.02 (101:50), 2.04 (102:50), 2.10 (105:50) of Ba/Cu (Ba:Cu) composition from the stoichiometric ratio 2:1 have been found for the known Ba{sub 2}CuO{sub 3+{delta}} oxides in the subsolidus region 900-970 deg. C. Unit cell parameters of the 101:50 orthorhombic oxide, 102:50 tetragonal one, 105:50 orthorhombic one are, respectively, a=4.049, b=3.899, c=13.034 A; a=3.985, c=12.968 A; a=4.087, b=3.897 and c=12.950 A. ED patterns of the 101:50, 102:50, 105:50 oxides show characteristic supercell reflections with the respective vector 1/60[5 4 0], {approx}2/11<1 1 0> and 1/6[2 0 0]. Oxides of the 2:1, 7:4, 5:3 and 23:20 compositions have been found in the crystallization region 970-1050 deg. C. Unit cell parameters of the 2:1 orthorhombic oxide are a=4.095, b=3.795, c=13.165 A. Interplanar spacings and X-ray characteristic peak intensities of the 7:4, 5:3 and 23:20 oxides are given. Oxides 2:1 and 7:4 melt pseudocongruently at 1020 and 1005 deg. C, oxides 5:3 and 23:20 melt incongruently at 995 and 980 deg. C, respectively. A diagram of the phase relations in the studied region of the BaO-CuO{sub x} system has been constructed, whose structure is considered as the total projection of phase states of the system existing for different x. - Graphical Abstract: A diagram of phase relations in the BaO-CuO{sub x} system in the range of 30.0-45.0 mol% CuO at 900-1050 deg. C at P(O{sub 2})=21 kPa (air) constructed on the data obtained by visual polythermal analysis (the liquidus line), XRD and ED with elemental analysis. Highlights: > A combination of physical

  14. Strongly enhanced vortex pinning from 4 to 77 K in magnetic fields up to 31 T in 15 mol.% Zr-added (Gd, Y)-Ba-Cu-O superconducting tapes

    NASA Astrophysics Data System (ADS)

    Xu, A.; Delgado, L.; Khatri, N.; Liu, Y.; Selvamanickam, V.; Abraimov, D.; Jaroszynski, J.; Kametani, F.; Larbalestier, D. C.

    2014-04-01

    Applications of REBCO coated conductors are now being developed for a very wide range of temperatures and magnetic fields and it is not yet clear whether vortex pinning strategies aimed for high temperature, low field operation are equally valid at lower temperatures and higher fields. A detailed characterization of the superconducting properties of a 15 mol. % Zr-added REBCO thin film made by metal organic chemical vapor deposition, from 4.2 to 77 K under magnetic fields up to 31 T is presented in this article. Even at a such high level of Zr addition, Tc depression has been avoided (Tc = 91 K), while at the same time an exceptionally high irreversibility field Hirr ≈ 14.8 T at 77 K and a remarkably high vortex pinning force density Fp ≈ 1.7 TN/m3 at 4.2 K have been achieved. We ascribe the excellent pinning performance at high temperatures to the high density (equivalent vortex matching field ˜7 T) of self-assembled BZO nanorods, while the low temperature pinning force is enhanced by large additional pinning which we ascribe to strain-induced point defects induced in the REBCO matrix by the BZO nanorods. Our results suggest even more room for further performance enhancement of commercial REBCO coated conductors and point the way to REBCO coil applications at liquid nitrogen temperatures since the critical current density Jc(H//c) characteristic at 77 K are now almost identical to those of fully optimized Nb-Ti at 4 K.

  15. Strongly enhanced vortex pinning from 4 to 77 K in magnetic fields up to 31 T in 15 mol.% Zr-added (Gd, Y)-Ba-Cu-O superconducting tapes

    SciTech Connect

    Xu, A; Delgado, L; Khatri, N; Liu, Y; Selvamanickam, V; Abraimov, D; Jaroszynski, J; Kametani, F; Larbalestier, DC

    2014-04-01

    Applications of REBCO coated conductors are now being developed for a very wide range of temperatures and magnetic fields and it is not yet clear whether vortex pinning strategies aimed for high temperature, low field operation are equally valid at lower temperatures and higher fields. A detailed characterization of the superconducting properties of a 15 mol.% Zr-added REBCO thin film made by metal organic chemical vapor deposition, from 4.2 to 77 K under magnetic fields up to 31 T is presented in this article. Even at a such high level of Zr addition, T-c depression has been avoided (T-c = 91 K), while at the same time an exceptionally high irreversibility field H-irr approximate to 14.8 T at 77 K and a remarkably high vortex pinning force density F-p approximate to 1.7 TN/m(3) at 4.2 K have been achieved. We ascribe the excellent pinning performance at high temperatures to the high density (equivalent vortex matching field similar to 7 T) of self-assembled BZO nanorods, while the low temperature pinning force is enhanced by large additional pinning which we ascribe to strain-induced point defects induced in the REBCO matrix by the BZO nanorods. Our results suggest even more room for further performance enhancement of commercial REBCO coated conductors and point the way to REBCO coil applications at liquid nitrogen temperatures since the critical current density J(c)(H//c) characteristic at 77 K are now almost identical to those of fully optimized Nb-Ti at 4 K. (C) 2014 Author(s).

  16. Gd1.96-xYxEu0.04O3 (x = 0.0, 0.49, 0.98, 1.47, 1.96 mol%) nanophosphors: Propellant combustion synthesis, structural and luminescence studies

    NASA Astrophysics Data System (ADS)

    Shilpa, C. J.; Dhananjaya, N.; Nagabhushana, H.; Sharma, S. C.; Shivakumara, C.; Sudheerkumar, K. H.; Nagabhushana, B. M.; Chakradhar, R. P. S.

    2014-07-01

    Gd1.96-xYxEu0.04O3 (x = 0.0, 0.49, 0.98, 1.47, 1.96 mol%) nanophosphors were synthesized by propellant combustion method at low temperature (400 °C). The powder X-ray diffraction patterns of as formed Gd1.96Eu0.04O3 showed monoclinic phase, however with the addition of yttria it transforms from monoclinic to pure cubic phase. The porous nature increases with increase of yttria content. The particle size was estimated from Scherrer's and W-H plots which was found to be in the range 30-40 nm. These results were in well agreement with transmission electron microscopy studies. The optical band gap energies estimated were found to be in the range 5.32-5.49 eV. PL emission was recorded under 305 nm excitation show an intense emission peak at 611 nm along with other emission peaks at 582, 641 nm. These emission peaks were attributed to the transition of 5D0 → 7FJ (J = 0, 1, 2, 3) of Eu3+ ions. It was observed that PL intensity increases with increase of Y content up to x = 0.98 and thereafter intensity decreases. CIE color co-ordinates indicates that at x = 1.47 an intense red bright color can be achieved, which could find a promising application in flat panel displays. The cubic and monoclinic phases show different thermoluminescence glow peak values measured under identical conditions. The response of the cubic phase to the applied dose showed good linearity, negligible fading, and simple glow curve structure than monoclinic phase indicating that suitability of this phosphor in dosimetric applications.

  17. Retraction RETRACTION of "Association between polymorphisms in the XRCC1 gene and the risk of non-small cell lung cancer", by Han JC, Zhang YJ and Li XD - Genet. Mol. Res. 14 (4): 12888-12893 (2015).

    PubMed

    Han, J C; Zhang, Y J; Li, X D

    2016-10-07

    The retracted article is: Han JC, Zhang YJ and Li XD (2015). Association between polymorphisms in the XRCC1 gene and the risk of non-small cell lung cancer. Genet. Mol. Res. 14: 12888-12893. The GMR editorial staff was alerted about this article (received on May 3, 2015; accepted on August 18, 2015) published on October 21, 2015 (DOI: 10.4238/2015.October.21.9) that was found to be substantially similar to the publication of "Association of XRCC1 gene polymorphisms with risk of non-small cell lung cancer" (received on January 25, 2015; accepted on March 23, 2015; e-published on April 1, 2015) by Kang et al., published in the International Journal of Clinical Experimental Pathology 8 (4): 4171-4176. The authors were aware of the Kang et al.'s paper, since they cite it several times in the manuscript published in GMR. Some of the language is similar between the two manuscripts, but what is the most concerning is that several of the tables in the papers are nearly identical. Tables 2 and 3 are exactly identical between the two articles, suggesting that the publication in GMR was plagiarized from the publication in the International Journal of Clinical Experimental Pathology. The Publisher and Editor decided to retract these articles in accordance with the recommendations of the Committee on Publication Ethics (COPE). After a thorough investigation, we have strong reason to believe that the peer review process was failure and, after review and contacting the authors, the editors of Genetics and Molecular Research decided to retract the article. The authors and their institutions were advised of this serious breach of ethics.

  18. Final report of the pilot study CCQM-P110-B1: A comparison of nitrogen dioxide (NO2) in nitrogen standards at 10 µmol/mol by Fourier transform infrared spectroscopy (FT-IR)

    NASA Astrophysics Data System (ADS)

    Flores, Edgar; Idrees, Faraz; Moussay, Philippe; Viallon, Joële; Wielgosz, Robert; Fernández, Teresa; Aoki, Nobuyuki; Kato, Kenji; Jeongsoon, Lee; Moon, Dongmin; Kim, Jin-Seog; Harling, A.; Milton, M.; Smeulders, Damian; Guenther, Franklin R.; Gameson, Lyn; Botha, Angelique; Tshilongo, James; Godwill Ntsasa, Napo; Valková, Miroslava; Konopelko, Leonid A.; Kustikov, Yury A.; Ballandovich, Vladimir S.; Gromova, Elena V.; Tuma, Dirk; Kohl, Anka; Schulz, Gert

    2012-01-01

    This pilot study compares the performance of participants in analyzing gas mixtures of nitrogen dioxide in nitrogen by comparison with in-house gravimetric standards using Fourier transformed infrared spectroscopy (FT-IR). In this study the same gas mixtures were used as in the key comparison CCQM-K74, which was designed to evaluate the level of comparability of National Metrology Institutes' measurement capabilities for nitrogen dioxide (NO2) at a nominal mole fraction of 10 µmol/mol. In the comparison CCQM-K74 most of the participants used chemiluminescence, with a small number using UV absorption or FT-IR spectroscopy, and thus it is of interest to improve understanding of the comparative performance of these techniques because they do not exhibit any cross-sensitivity to nitric acid (HNO3), which was known to be present in the mixtures used for the comparison. The results of this pilot study indicate good consistency and a level of agreement similar to that reported in the comparison CCQM-K74, demonstrating that FT-IR can be operated as a comparison method when calibrated with appropriate gas standards and can achieve similar measurement uncertainties to chemiluminescence and UV absorption techniques. An additional pilot study, CCQM-P110-B2, was conducted on the same gas mixtures in parallel with this pilot study. The second study addressed FT-IR spectroscopy when used to measure the gas mixtures with respect to reference spectra. The results of this second study will be reported elsewhere. Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCQM-GAWG.

  19. 46 CFR 111.10-4 - Power requirements, generating sources.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... generators which supply both ship's service and propulsion power do not need additional ship's service generators provided that with any one propulsion/ship's service generator out of service the capacity of the...) The aggregate capacity of the electric ship's service generating sources required in § 111.10-3...

  20. 46 CFR 111.10-4 - Power requirements, generating sources.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... generators which supply both ship's service and propulsion power do not need additional ship's service generators provided that with any one propulsion/ship's service generator out of service the capacity of the...) The aggregate capacity of the electric ship's service generating sources required in § 111.10-3...

  1. 40 CFR 10.4 - Evidence to be submitted.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... such expenses. (7) If damages for pain and suffering prior to death are claimed, a physician's detailed statement specifying the injuries suffered, duration of pain and suffering, any drugs administered for pain... pain and suffering, the claimant may be required to submit the following evidence or information: (1)...

  2. 40 CFR 10.4 - Evidence to be submitted.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... such expenses. (7) If damages for pain and suffering prior to death are claimed, a physician's detailed statement specifying the injuries suffered, duration of pain and suffering, any drugs administered for pain... pain and suffering, the claimant may be required to submit the following evidence or information: (1)...

  3. 40 CFR 10.4 - Evidence to be submitted.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... such expenses. (7) If damages for pain and suffering prior to death are claimed, a physician's detailed statement specifying the injuries suffered, duration of pain and suffering, any drugs administered for pain... pain and suffering, the claimant may be required to submit the following evidence or information: (1)...

  4. 40 CFR 10.4 - Evidence to be submitted.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., nature and extent of treatment, any degree of temporary or permanent disability, the prognosis, period of.... (2) Itemized bills for medical, dental, hospital and related expenses incurred, or itemized receipts of payment for such expenses. (3) If the prognosis reveals the necessity for future treatment,...

  5. 40 CFR 10.4 - Evidence to be submitted.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., nature and extent of treatment, any degree of temporary or permanent disability, the prognosis, period of.... (2) Itemized bills for medical, dental, hospital and related expenses incurred, or itemized receipts of payment for such expenses. (3) If the prognosis reveals the necessity for future treatment,...

  6. 17 CFR 10.4 - Business address; hours.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Centre, 1155 21st Street NW., Washington, DC 20581. It is open each day, except Saturdays, Sundays and... time, whichever is currently in effect in Washington, DC. If Commission personnel are present in...

  7. 32 CFR 10.4 - Policies and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-Citizens in the War Against Terrorism,” punitive measures imposed under 10 U.S.C. 898, and any other lawful... of November 13, 2001, “Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism,” may be subject to appropriate action by the Appointing Authority, the General Counsel of...

  8. 32 CFR 10.4 - Policies and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-Citizens in the War Against Terrorism,” punitive measures imposed under 10 U.S.C. 898, and any other lawful... of November 13, 2001, “Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism,” may be subject to appropriate action by the Appointing Authority, the General Counsel of...

  9. 32 CFR 10.4 - Policies and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-Citizens in the War Against Terrorism,” punitive measures imposed under 10 U.S.C. 898, and any other lawful... of November 13, 2001, “Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism,” may be subject to appropriate action by the Appointing Authority, the General Counsel of...

  10. 32 CFR 10.4 - Policies and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-Citizens in the War Against Terrorism,” punitive measures imposed under 10 U.S.C. 898, and any other lawful... of November 13, 2001, “Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism,” may be subject to appropriate action by the Appointing Authority, the General Counsel of...

  11. 32 CFR 10.4 - Policies and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-Citizens in the War Against Terrorism,” punitive measures imposed under 10 U.S.C. 898, and any other lawful... of November 13, 2001, “Detention, Treatment, and Trial of Certain Non-Citizens in the War Against Terrorism,” may be subject to appropriate action by the Appointing Authority, the General Counsel of...

  12. 17 CFR 10.4 - Business address; hours.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... in other matters within the scope of this part. Legal holidays include New Year's Day, Washington's Birthday, Memorial Day, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving Day... Centre, 1155 21st Street NW., Washington, DC 20581. It is open each day, except Saturdays, Sundays...

  13. The radiolysis of iodine in aqueous solutions containing methane

    NASA Astrophysics Data System (ADS)

    Paquette, Jean; Ford, Beverly L.

    The γ-radiolysis of iodine, iodine, iodate and periodate solutions containing methane has been investigated. Iodoalkanes are produced in these solutions upon irradiation. In the case of unbuffered iodine, iodate and periodate solutions at an initial concentration of 1.0 × 10 -4 mol dm -3, nearly all of the initial iodine is transformed into iodoalkanes after the absorption of a 4 kGy radiation dose. The yield of iodoalkanes is lower for iodine solutions and for iodide solutions buffered at neutral pH. It is concluded that the main reactions leading to the formation of iodoalkanes are CH 3+I 2→CH 3I+I and CH 3+I→CH 3I. In the case of iodate and periodate, these reactions could be preceeded by reactions involving the methyl radical and oxyiodine species: CH 3+IO x→CH 2O+HIO x-1.

  14. Radiolysis of solutions containing organo-disulphides

    NASA Astrophysics Data System (ADS)

    Elliot, Allen John; Simsons, Anita Sandra; Sopchyshyn, Frederick Charles

    When oxidized dithiothreitol (DTT- ox), oxidized gluthathione (GSSG), or dithiodiproprionic acid is radiolysed in N 2O-saturated sodium formate solutions, a chain reduction of the disulphide to the corresponding thiol occurs. The chain propagating step is the abstraction of the hydrogen atom in the formate ion by the thiyl radical. For the dithiothreitol thiyl radical, the rate constant for the abstraction is ≥ 3.6 × 10 4 mol -1 dm 3 s -1. The more sterically hindered penicillamine disulphide does not undergo this chain reaction. While the (CH 3) 2ĊOH radical does not reduce DTT- ox, it reduces GSSG to glutathione. At pH 9, the acetone radical anion, (CH 3) 2ĊO -, reduces both DTT- ox and GSSG.

  15. The inhibition of calcium carbonate crystal growth by the cysteine-rich Mdm2 peptide.

    PubMed

    Dalas, E; Chalias, A; Gatos, D; Barlos, K

    2006-08-15

    The crystal growth of calcite, the most stable calcium carbonate polymorph, in the presence of the cysteine-rich Mdm2 peptide (containing 48 amino acids in the ring finger configuration), has been investigated by the constant composition technique. Crystallization took place exclusively on well-characterized calcite crystals in solutions supersaturated only with respect to this calcium carbonate salt. The kinetic results indicated a surface diffusion spiral growth mechanism. The presence of the Mdm2 peptide inhibited the crystal growth of calcite by 22-58% in the concentration range tested, through adsorption onto the active growth sites of the calcite crystal surface. The kinetic results favored a Langmuir-type adsorption model, and the value of the calculated affinity constant was k(aff)=147x10(4) dm(3)mol(-1), a(ads)=0.29.

  16. Crystal structure of 5-amino-5'-chloro-6-(4-chloro-benzo-yl)-8-nitro-2,3-di-hydro-1H-spiro-[imidazo[1,2-a]pyridine-7,3'-indolin]-2'-one including an unknown solvent mol-ecule.

    PubMed

    Nagalakshmi, R A; Suresh, J; Sivakumar, S; Kumar, R Ranjith; Lakshman, P L Nilantha

    2014-09-01

    The asymmetric unit of the title compound, C21H15Cl2N5O4, contains two independent mol-ecules (A and B) having similar conformations. The amine (NH2) group forms an intra-molecular hydrogen bond with the benzoyl group, giving an S(6) ring motif in both mol-ecules. The central six-membered rings adopt sofa conformations and the imidazole rings are planar (r.m.s deviations = 0.0150 and 0.0166 Å). The pyridine and imidazole rings are inclined to one another by 3.54 (1) and 3.03 (1)° in mol-ecules A and B, respectively. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains along the a axis which enclose R 2 (2)(16) ring motifs. The rings are linked by weak N-H⋯O and C-H⋯O hydrogen bonds and C-H⋯π inter-actions forming sheets lying parallel to (001). A region of disordered electron density, most probably disordered solvent mol-ecules, occupying voids of ca 753 Å(3) for an electron count of 260, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

  17. Spectrophotometric determination of lithium ion using a water-soluble octabromoporphyrin in aqueous solution.

    PubMed

    Tabata, M; Nishimoto, J; Kusano, T

    1998-08-01

    A water-soluble porphyrin, (2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin; H(2)obtpps(4-)) was synthesized and developed for the determination of lithium ion in aqueous solution. The octabromo groups lower the basicity of the porphyrin by their electron-withdrawing effect, and enable the porphyrin to react with the lithium ion in alkaline solution to form the lithium complex along with a shift of absorption maximum: lambda max/nm (logepsilon/mol(-1) dm(3) cm(-1)) of the lithium porphyrin are 490.5 nm (5.31) and 734 nm (4.36). Sodium and potassium ions did not react with the porphyrin. The equilibrium constant for the reaction Li(+)+Hobtpps(5-)right harpoon over left harpoon[Li(obtpps)](5-)+H(+) was found to be 10(-8.80) and the conditional formation constant of the [Li(obtpps)](5-) at pH 13 is 10(4.21). The above results were applied to the determination of lithium ion in aqueous solution. The interference from transition and heavy metal ions was masked by using N,N'-1,2-ethanediylbis[N(carboxylmethy)glycinato]magnesium(II) ([Mg(edta)](2-)) solution. Absorbance at 490 nm was measured against a blank solution. A calibration graph was linear over the range of 0.007-0.7 mug cm(-3) (1x10(-6)-1x10(-4) mol dm(-3)) of lithium(I) with a correlation factor of 0.967. Lithium ion less than ppm level was determined spectrophtometrically in aqueous solution. The proposed method was applied to the determination of lithium in human serum and sea water samples.

  18. Diagnostic moléculaire d'helicobacter pylori par PCR chez les patients en consultation gastroentérologique au Centre Médical Saint Camille de Ouagadougou

    PubMed Central

    Werme, Karidia; Bisseye, Cyrille; Ouedraogo, Issiaka; Yonli, Albert Théophane; Ouermi, Djénèba; Djigma, Florencia; Moret, Rémy; Gnoula, Charlemagne; Nikiema, Jean-Baptiste; Simpore, Jacques

    2015-01-01

    Introduction L'infection par Helicobacter pylori constitue un problème de santé publique notamment dans les pays en développement. Elle entraine une gastrite pouvant évoluer vers des formes sévères d'ulcération et de transformation maligne. La présenté étude avait pour objectif de diagnostiquer H. pylori par des techniques sérologique et moléculaire au Burkina Faso. Méthodes L’étude prospective a été conduite de mars à juin 2012 sur 70 patients venus en consultation dans le service de gastroentérologie au Centre Médical Saint Camille. Le diagnostic de H. pylori a été réalisé par le test ELISA Immunocomb (ORGENICS Ltd, Yavne, Israël) et la PCR sur des biopsies gastriques prélevées sur les patients. Résultats Les pathologies gastroduodénales étaient plus fréquentes chez les patients de plus de 45 ans. Les prévalences de H. pylori étaient respectivement de 88,57% et de 91,43% par sérologie Immunocomb et par PCR. La différence entre les deux techniques n’était pas significative (P = 0,573). La performance de la PCR a été comparée à celle de la technique Immunocomb. Les résultats montrent une sensibilité et une spécificité de 92,2% et 50,0% pour la technique Immunocomb. Conclusion Le diagnostic de H. pylori par PCR est plus spécifique que le test sérologique Immunocomb et devrait être introduit dans le diagnostic de routine de cette bactérie pathogène au Burkina Faso. PMID:26327960

  19. Channels with ordered water and bipyridine mol-ecules in the porous coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10N2H8·5H2O} n.

    PubMed

    Aubert, Emmanuel; Doudouh, Abdelatif; Peluso, Paola; Mamane, Victor

    2016-11-01

    The coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10H8N2·5H2O} n , systematic name: poly[[bis-(μ2-4,4'-bi-pyridine)(μ2-hexa-fluorido-silicato)copper(II)] 4,4'-bi-pyridine disolvate penta-hydrate], contains pores which are filled with water and 4,4'-bi-pyridine mol-ecules. As a result of the presence of these ordered species, the framework changes its symmetry from P4/mmm to P21/c. The 4,4'-bi-pyridine guest mol-ecules form chains inside the 6.5 × 6.9 Å pores parallel to [100] in which the mol-ecules inter-act through π-π stacking. Ordered water mol-ecules form infinite hydrogen-bonded chains inside a second pore system (1.6 × 5.3 Å free aperture) perpendicular to the 4,4'-bi-pyridine channels.

  20. Raman spectra of crystals LiNbO3:Zn(4.5), LiNbO3:Mg:Fe(5.01, 0.005), LiNbO3:Mg(5.1), and LiNbO3:Mg(5.3 mol %)

    NASA Astrophysics Data System (ADS)

    Sidorov, N. V.; Gabain, A. A.; Yanichev, A. A.; Efremov, I. N.; Biryukova, I. V.; Palatnikov, M. N.

    2015-02-01

    We have investigated the Raman spectra of strongly doped crystals that were grown from batches of different genesis. The LiNbO3:Mg(5.3 mol %) and LiNbO3:Mg:Fe(5.01, 0.005 mol %) crystals were obtained using methods of homogeneous doping and the LiNbO3:Mg(5.1 mol %) crystal was obtained using a solid-phase master addition alloy, while the LiNbO3:Zn(4.5 mol %) crystal was grown using direct doping. In the Y( ZZ){ie269-1} scattering geometry, we have revealed the occurrence of lines in the spectrum that correspond to fundamental vibrations of the A 2 symmetry species, which are forbidden by the selection rules for the {ie269-2} space group. The occurrence of lines in the spectrum that correspond to fundamental vibrations of the A 2 symmetry species has been explained by the existence of microstructures and clusters in strongly doped LiNbO3 crystals, which lead to significant local changes in the symmetry of the crystal.

  1. Channels with ordered water and bipyridine mol­ecules in the porous coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10N2H8·5H2O}n

    PubMed Central

    Aubert, Emmanuel; Doudouh, Abdelatif; Peluso, Paola; Mamane, Victor

    2016-01-01

    The coordination polymer {[Cu(SiF6)(C10H8N2)2]·2C10H8N2·5H2O}n, systematic name: poly[[bis­(μ2-4,4′-bi­pyridine)(μ2-hexa­fluorido­silicato)copper(II)] 4,4′-bi­pyridine disolvate penta­hydrate], contains pores which are filled with water and 4,4′-bi­pyridine mol­ecules. As a result of the presence of these ordered species, the framework changes its symmetry from P4/mmm to P21/c. The 4,4′-bi­pyridine guest mol­ecules form chains inside the 6.5 × 6.9 Å pores parallel to [100] in which the mol­ecules inter­act through π–π stacking. Ordered water mol­ecules form infinite hydrogen-bonded chains inside a second pore system (1.6 × 5.3 Å free aperture) perpendicular to the 4,4′-bi­pyridine channels. PMID:27840730

  2. Transients and cooperative action of β-carotene, vitamin E and C in biological systems in vitro under irradiation

    NASA Astrophysics Data System (ADS)

    Getoff, Nikola; Platzer, Isabel; Winkelbauer, Cornelia

    1999-08-01

    Using N •3 species as specific electron acceptor a defined ascorbate radical: AH •↔A •-+H + (λ max=360 nm, ɛ=3400 dm 3 mol -1 cm -1) is observed. The attack of DMSO •+ on vit.E results in a vit.E • radical ( k=1×10 9 dm 3 mol -1 s -1; λ max=425 nm, ɛ=2400 dm 3 mol -1 cm -1; 2 k=4.7×10 8 dm 3 mol -1 s -1). Vit.E-acetate leads to the formation of a radical cation (vit.E-ac •+). β-carotene reacts also with DMSO •+ forming a radical cation, β-car •+ ( k=1.75×10 8 dm 3 mol -1 s -1; λ max=942 nm, ɛ=14 600 dm 3 mol -1 cm -1), which probably leads to the formation of a dimer radical cation, (β-car) •+2 ( k=2.5×10 7 dm 3 mol -1 s -1). Using E.coli bacteria (AB1157) as a model system in vitro it was found that all three vitamins are rather efficient radiation protecting agents. They can also increase the activity of cytostatica, e.g., mitomycin C (MMC), by electron transfer process. The mixture of vit.E-ac and β-car acts contradictory, but adding vit.C to it a strong cooperative enhancement of the MMC activity is observed once again. A relationship between the pulse radiolysis and the radiation biological data is found and discussed. A possible explanation of the previously reported trials concerning the role of vit.E and β-car on the increased occurence of lung and other types of cancer in smokers and drinkers is presented.

  3. Effect of different experimental parameters on the potentiometric evaluation of blood electrolytes using K+ as a test cation.

    PubMed

    Oliveira, C M; Rebelo, M J; Camões, M F

    1996-12-01

    Potentiometric evaluation of ionic concentrations in physiological media has been reported to be significantly affected by the albumin containing matrix. Previous studies have attempted to clarify the origin of different patterns of variation of E versus albumin concentration at a constant 0.01 mol dm-3 KCl, depending on the experimental methodologies. This paper reports on measurements of K+ in albumin (BSA) containing KCl solutions, which have been pursued following different methodologies concerning the sequence of measurements, i.e., starting either from the most concentrated solution (100 g dm-3) (A) or from the most dilute solution (20 g dm-3) (B), and solution preparation, (a) dilution of an initial 100 g dm-3 albumin solution by successive addition of 0.01 mol dm-3 KCl, (b) concentration of an initial 20 g dm-3 albumin solution by addition of solid substance, (c) independent preparation of each albumin solution (20, 40, 60, 80 and 100 g dm-3) or (d) preparation of each albumin solution from direct dilution of a 100 g dm-3 stock solution with 0.01 mol dm-3 KCl. Convenient calculations were made and showed a significant contribution of albumin to the liquid-liquid junction potential. The variation of potential with albumin concentration is smaller for hypertonic than for isotonic bridge solutions, both for the dilution series (A,a and A,d) and for the concentration series (B,c and B,d). When the method for increasing the concentration is performed by addition of a solid substance to an initially diluted albumin (B,b), the slope of the E versus albumin concentration plot is larger for hypertonic than for isotonic reference electrolytes. This latter finding is in agreement with Payne's results when ultrafiltration was used to concentrate a protein solution. These observations are a clear indication that the method of preparation of concentrated protein solutions may significantly affect the results.

  4. Computational Study of (13)C NMR Chemical Shift Anisotropy Patterns in C20H10 and [C20H10](4-). Insights into Their Variation upon Planarization and Formation of Concentric Aromatic Species in the Smaller Isolated-Pentagon Structural Motif.

    PubMed

    Muñoz-Castro, Alvaro; Caimanque-Aguilar, Wilson; Morales-Verdejo, Cesar

    2017-04-06

    Corannulene, C20H10, exhibits a concave surface in the ground state that is able to experience a bowl-to-bowl inversion through a planar conformation. Such a structure is the smaller example resembling an isolated-pentagon motif, as a relevant fragment in fullerene chemistry. Here, we explored the differences between bowl and planar conformations involving both energetic and (13)C NMR properties, for the neutral and tetraanionic species by using density functional theory (DFT) methods. This allows us to understand the variation of the chemical environment at the carbon atoms upon planarization of this representive motif. Our results reveal that the variation of the chemical shift comes about from the variation of different main components of the shielding tensor, according to the relative position of the carbon atoms in the structure (i.e., rim, hub, and protonated), which is more relevant for both hub and protonated sites, in contrast to the rim carbon remaining almost unshifted. Interestingly, the planar transition state exhibits a more favorable bonding situation than the bowl-shaped conformation; however, the higher strain is enough to overcome this extra stabilization. Upon reduction to the tetraanionic counterpart (C20H10(4-)), a lesser strain in the planar conformation is observed, decreasing the inversion barrier. In addition, the formation of the concentric aromatic ring systems in C20H10(4-), results in a more axially symmetric chemical shift anisotropy (CSA) tensor for the hub carbons, accounting in a local manner, for the concentric aromatic behavior in such structure in contrast to the neutral parent. These observations can be useful to evaluate the aromatic behavior of teh isolated-pentagon rule (IPR) motif in fullerene cages.

  5. The effect of coadsorbent and solvent on the photovoltaic performance of 2,9,16,23-Tetrakis(7-coumarinoxy-4-methyl)-phthalocyaninatocopper-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Fei; Wang, Shi-Rong; Li, Xiang-Gao; Xiao, Yin; Guo, Jun-Jie

    2016-03-01

    The synthesis, characterization and thermal properties of CuPc-Cou were reported and the effects of chenodeoxycholic acid (CHENO) as a coadsorbent and the solvent on the solar cell's performance were investigated. The ground state absorbance of CuPc-Cou showed the molar extinction coefficients as high as 2.90 × 104 dm3 mol-1 cm-1 in DMF and 2.74 × 104 dm3 mol-1 cm-1 in CH2Cl2. The thermal stability studies indicated that CuPc-Cou was stable up to 370 °C. Furthermore, HOMO and LUMO energies made it clear that CuPc-Cou can be used as a sensitizer for DSSC. Adding CHENO onto TiO2 nanoparticles not only reduced the adsorption of phthalocyanine sensitizers but also prevented the aggregation behavior, leading to different photovoltaic performance. The open circuit voltage of the solar cells with CHENO coadsorbent increased due to the enhanced electron lifetime in TiO2 nanoparticles coupled with the band edge shift of TiO2 to negative potentials. The optimal dye adsorption condition of the TiO2 electrode was found to be 3 × 10-4 M CuPc-Cou solution containing 6.0 mM CHENO in dichloromethane, which could contribute to improve the PCE by 69% as compared to the solar cell fabricated with TiO2 electrode sensitized by the CuPc-Cou in absence of CHENO and the optimal condition in DMF. It indicated that CuPc-Cou in DMF was easy to aggregate than in CH2Cl2 for the solvent effect.

  6. Single and combined supplementation of glutamine and n-3 polyunsaturated fatty acids on host tolerance and tumour response to 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin (CPT-11)/5-fluorouracil chemotherapy in rats bearing Ward colon tumour.

    PubMed

    Xue, Hongyu; Le Roy, Séverine; Sawyer, Michael B; Field, Catherine J; Dieleman, Levinus A; Baracos, Vickie E

    2009-08-01

    Prior reports suggest that during irinotecan (7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxy-camptothecin; CPT-11) chemotherapy in laboratory rats, the anti-tumour efficacy and diarrhoea toxicity could be modulated by n-3 PUFA and glutamine, respectively. We further examined how these two dietary elements, when provided individually and in combination, would affect the efficacy of a cyclical regimen of CPT-11/5-fluorouracil (5-FU), an accepted combination regimen for colorectal cancer. Prior to initiating chemotherapy, diets enriched either with glutamine (2 %, w/w total diet) or n-3 PUFA (0.88 %, w/w total diet) alone, inhibited Ward colon tumour growth (P < 0.05). These diets also completely or partially normalized the changes in peripheral leucocyte counts associated with the tumour-bearing state (e.g. neutrophil proportion/concentration and lymphocyte proportion). During chemotherapy, either glutamine- or n-3 PUFA-enriched diet enhanced tumour chemo-sensitivity, and reduced body weight loss, anorexia and muscle wasting (v. animals fed control diet, P < 0.05). Surprisingly, providing both glutamine and n-3 PUFA together did not confer a greater benefit on tumour inhibition either in the presence or absence of chemotherapy; individual benefits associated with single treatments, particularly in respect to host nutritional status (i.e. body weight, food intake and muscle weight) and immune (peripheral leucocyte counts) features were instead partially or completely lost when these two nutrients were combined. These results draw into question the common assumption that there are additive or synergistic benefits of combinations of nutrients, which are beneficial on an individual basis, and suggest that co-supplementation with glutamine and n-3 PUFA is not indicated during chemotherapy with CPT-11 and 5-FU.

  7. Ionic molal conductivities, activity coefficients, and dissociation constants of HAsO42− and H2AsO4− from 5 to 90°C and ionic strengths from 0.001 up to 3 mol kg−1 and applications in natural systems

    USGS Publications Warehouse

    Zhu, Xiangyu; Nordstrom, D. Kirk; McCleskey, R. Blaine; Wang, Rucheng

    2016-01-01

    Arsenic is known to be one of the most toxic inorganic elements, causing worldwide environmental contamination. However, many fundamental properties related to aqueous arsenic species are not well known which will inhibit our ability to understand the geochemical behavior of arsenic (e.g. speciation, transport, and solubility). Here, the electrical conductivity of Na2HAsO4 solutions has been measured over the concentration range of 0.001–1 mol kg−1 and the temperature range of 5–90°C. Ionic strength and temperature-dependent equations were derived for the molal conductivity of HAsO42−and H2AsO4− aqueous ions. Combined with speciation calculations and the approach used by McCleskey et al. (2012b), these equations can be used to calculate the electrical conductivities of arsenic-rich waters having a large range of effective ionic strengths (0.001–3 mol kg−1) and temperatures (5–90°C). Individual ion activity coefficients for HAsO42− and H2AsO4− in the form of the Hückel equation were also derived using the mean salt method and the mean activity coefficients of K2HAsO4 (0.001–1 mol kg−1) and KH2AsO4 (0.001–1.3 mol kg−1). A check on these activity coefficients was made by calculating mean activity coefficients for Na2HAsO4 and NaH2AsO4 solutions and comparing them to measured values. At the same time Na-arsenate complexes were evaluated. The NaH2AsO40 ion pair is negligible in NaH2AsO4 solutions up to 1.3 mol kg−1. The NaHAsO4− ion pair is important in NaHAsO4 solutions >0.1 mol kg−1 and the formation constant of 100.69 was confirmed. The enthalpy, entropy, free energy and heat capacity for the second and third arsenic acid dissociation reactions were calculated from pH measurements. These properties have been incorporated into a widely used geochemical calculation code WATEQ4F and applied to natural arsenic waters. For arsenic spiked water samples from Yellowstone National Park, the mean difference between the

  8. Graft [partially carboxymethylated guar gum-g-poly N-(hydroxymethyl) acrylamide] copolymer: from synthesis to applications.

    PubMed

    Pandey, Vijay Shankar; Verma, Shiv Kumar; Behari, Kunj

    2014-09-22

    Graft copolymer of N-(hydroxymethyl) acrylamide with carboxymethylated guar gum was synthesized and the reaction conditions were optimized for better yield using potassium peroxymonosulfate and thiourea as a redox initiator. The optimum reaction conditions for grafting have also been determined by studying the effect of N-(hydroxymethyl) acrylamide, hydrogen ion, peroxymonosulphate, thiourea concentration and carboxymethylated guar gum along with time and temperature. Experimental results show that maximum grafting has been obtained at 1.4 g dm(-3) concentration of carboxymethylated guar gum and 16×10(-2) mol dm(-3) concentration of N-(hydroxymethyl) acrylamide. It has been observed that grafting ratio, add on, conversion, efficiency and rate of grafting increase up to 6.0×10(-3) mol dm(-3) of hydrogen ion, 2.4×10(-3) mol dm(-3) of thiourea, 14×10(-3) mol dm(-3) of peroxymonosulphate and 35°C of temperature. Grafted copolymer has been characterized by FTIR spectroscopy and thermogravimetric analysis. Water swelling, flocculating, and metal ion uptake properties of partially carboxymethylated guar gum-g-N-(hydroxymethyl) acrylamide have been determined.

  9. Synthesis, characterization and applications of graft copolymer (κ-carrageenan-g-vinylsulfonic acid).

    PubMed

    Yadav, Mithilesh; Sand, Arpit; Mishra, Madan Mohan; Tripathy, Jasaswini; Pandey, Vijay Shankar; Behari, Kunj

    2012-04-01

    The synthesis of graft copolymer (κ-carrageenan-g-vinylsulfonic acid) is carried out in nitrogen atmosphere using potassium peroxymonosulfate (PMS) and malonic acid (MA) as redox system. The effect of reaction variables including the concentration of vinylsulfonic acid 1.3×10(-2) to 6.7×10(-2) mol dm(-3), PMS 4×10(-3) to 20×10(-3) mol dm(-3), MA 1.6×10(-3) to 4.8×10(-3) mol dm(-3), sulfuric acid 1×10(-3) to 8×10(-3) mol dm(-3), κ-carrageenan 0.4-1.8 g dm(-3) as well as time duration 60-180 min and temperature 25-45 °C has been studied. The water swelling capacity of graft copolymer is investigated. Flocculation property for both coking and non-coking coals is studied for the treatment of coal mine waste water. The graft copolymer has been characterized by FTIR and thermogravimetric analysis.

  10. CO 2 and CO utilization: radiation-induced carboxylation of aqueous chloroacetic acid to malonic acid

    NASA Astrophysics Data System (ADS)

    Getoff, Nikola

    2003-07-01

    CO 2 and CO in addition to HCOOH/HCOO - can be used to produce the carboxylating radical rad COOH/ rad COO - under the influence of ionizing radiation. The carboxylation of ClCH 2COOH/ClCH 2COO - to malonic acid/malonate was studied at the pH range 2-7. A maximum yield G(malonic acid)=85 at pH=3 was observed by using 5×10 -2 mol dm -3 ClCH 2COOH, 1×10 -2 mol dm -3 HCOOH and 1×10 -3 mol dm -3 CO at a dose of 4.8 kGy. Oxalic and succinic acids were found as byproducts. The yield of the formed Cl - ions passes two maxima, at pH=3 ( G=7.5) and 7 ( G=15). Reaction mechanisms for the carboxylation process are presented.

  11. Crystal structure of cis-bis­{4-phenyl-1-[(3R)-1,7,7-tri­methyl-2-oxobi­cyclo­[2.2.1]heptan-3-ylidene]thio­semicarbazidato-κ3 O,N 1,S}cadmium(II) with an unknown solvent mol­ecule

    PubMed Central

    Nogueira, Vanessa Senna; Bresolin, Leandro; Näther, Christian; Jess, Inke; de Oliveira, Adriano Bof

    2015-01-01

    The reaction between the racemic mixture of the camphor-4-phenyl­thio­semicarbazone derivative and cadmium acetate dihydrate yielded the title compound, [Cd(C17H20N3OS)2]. The CdII ion is six-coordinated in a distorted octa­hedral environment by two deprotonated thio­semicarbazone ligands acting as an O,N,S-donor in a tridentate chelating mode, forming five-membered chelate rings. In the crystal, the mol­ecules are connected via pairs of N—H⋯S and C—H⋯S inter­actions, building centrosymmetric dimers. One of the ligands is disordered in the campher unit over two sets of sites with site-occupancy factors of 0.7 and 0.3. The structure contains additional solvent mol­ecules, which are disordered and for which no reasonable split model was found. Therefore, the data were corrected for disordered solvent using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9–18] in PLATON. Since the disordered solvents were removed by data processing, and the number of solvent entities was a suggestion only, they were not considered in the chemical formula and subsequent chemical or crystal information. PMID:26870441

  12. Crystal structure of cis-bis-{4-phenyl-1-[(3R)-1,7,7-tri-methyl-2-oxobi-cyclo-[2.2.1]heptan-3-ylidene]thio-semicarbazidato-κ(3) O,N (1),S}cadmium(II) with an unknown solvent mol-ecule.

    PubMed

    Nogueira, Vanessa Senna; Bresolin, Leandro; Näther, Christian; Jess, Inke; de Oliveira, Adriano Bof

    2015-12-01

    The reaction between the racemic mixture of the camphor-4-phenyl-thio-semicarbazone derivative and cadmium acetate dihydrate yielded the title compound, [Cd(C17H20N3OS)2]. The Cd(II) ion is six-coordinated in a distorted octa-hedral environment by two deprotonated thio-semicarbazone ligands acting as an O,N,S-donor in a tridentate chelating mode, forming five-membered chelate rings. In the crystal, the mol-ecules are connected via pairs of N-H⋯S and C-H⋯S inter-actions, building centrosymmetric dimers. One of the ligands is disordered in the campher unit over two sets of sites with site-occupancy factors of 0.7 and 0.3. The structure contains additional solvent mol-ecules, which are disordered and for which no reasonable split model was found. Therefore, the data were corrected for disordered solvent using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18] in PLATON. Since the disordered solvents were removed by data processing, and the number of solvent entities was a suggestion only, they were not considered in the chemical formula and subsequent chemical or crystal information.

  13. Primary photophysical properties of moxifloxacin--a fluoroquinolone antibiotic.

    PubMed

    Lorenzo, Fernando; Navaratnam, Suppiah; Edge, Ruth; Allen, Norman S

    2008-01-01

    The photophysical properties of the fluoroquinolone antibiotic moxifloxacin (MOX) were investigated in aqueous media. MOX in water, at pH 7.4, shows two intense absorption bands at 287 and 338 nm (epsilon = 44,000 and 17,000 dm(3) mol(-1) cm(-1), respectively). The absorption and emission properties of MOX are pH-dependent, pK(a) values for the protonation equilibria of both the ground (6.1 and 9.6) and excited singlet states (6.8 and 9.1) of MOX were determined spectroscopically. MOX fluoresces weakly, the quantum yield for fluorescence emission being maximum (0.07) at pH 8. Phosphorescence from the excited triplet state in frozen ethanol solution has a quantum yield of 0.046. Laser flash photolysis and pulse radiolysis studies have been carried out to characterize the transient species of MOX in aqueous solution. On laser excitation, MOX undergoes monophotonic photoionization with a quantum yield of 0.14. This leads to the formation of a long-lived cation radical whose absorption is maximum at 470 nm (epsilon(470) = 3400 dm(3) mol(-1) cm(-1)). The photoionization process releases hydrated electron which rapidly reacts (k = 2.8 x 10(10) dm(3) mol(-1) s(-1)) with ground state MOX, yielding a long-lived anion radical with maximum absorption at 390 nm (epsilon(390) = 2400 dm(3) mol(-1) cm(-1)). The cation radical of MOX is able to oxidize protein components tryptophan and tyrosine. The bimolecular rate constants for these reactions are 2.3 x 10(8) dm(3) mol(-1) s(-1) and 1.3 x 10(8) dm(3) mol(-1) s(-1), respectively. Singlet oxygen sensitized by the MOX triplet state was also detected only in oxygen-saturated D(2)O solutions, with a quantum yield of 0.075.

  14. Preparation and conductivity measurement of 7-8 mol % YSZ and 12 mol % CSZ for electrolyte SOFC

    NASA Astrophysics Data System (ADS)

    Budiana, B.; Fitriana, F.; Ayu, N.; Suasmoro, S.

    2016-08-01

    The study of 7YSZ (93% ZrO2-7%Y2O3), 8YSZ (92% ZrO2-8%Y2O3), and CSZ (88% ZrO2-12% CaO) as SOFC electrolytes have been carried out successfully. 7YSZ and 8YSZ powders were prepared by solid state reaction method of mixed Y2O3 and ZrO2 followed by calcination at 1350 °C for 1 hour, while CSZ was commercial products. Pellets of 7YSZ, 8YSZ, and CSZ were prepared by 1.2 gr, pressed at 40 MPa and sintered at 1550 °C for 4 hours. Rietveld refinement revealed that 7YSZ comprised 47.27% monoclinic, 52.65% cubic, and 0.008% Y2O3 cubic, while 8YSZ comprised 48.45% monoclinic, 49.32% cubic, 2.23% Y2O3 cubic and CSZ has 88% ZrO2 and 12% CaO. Ionic conductivity and activation energy were obtained from Cole- Cole Plot of impedance, the activation energy of 7YSZ=1.03eV, 8YSZ=0.96eV and CSZ=0.78eV.

  15. Effect of chromium salts on invertase immobilization onto carboxymethyl-cellulose-gelatine carrier system.

    PubMed

    Emregül, E; Sungur, S; Akbulut, U

    1996-07-01

    The carboxymethylcellulose-gelatine carrier system was investigated for invertase immobilization. Chromium (III) acetate, chromium (III) sulphate and potassium chromium (III) sulphate were used as cross-linking agents. Effect of carboxymethylcellulose-gelatine ratio and cross-linker concentration on immobilized enzyme activity were analysed. Reusability of immobilized enzyme was also investigated. Maximum immobilized enzyme activities were obtained with cross-linkers chromium (III) sulphate (0.004 mol dm-3) and potassium chromium (III) sulphate (0.001 mol dm-3) for a carrier composition of carboxymethylcellulose-gelatine ratio 0.111 (w/w) as 78%.

  16. A spectrophotometric study of the formation and deprotonation of thioarsenite species in aqueous solution at 22 °C

    NASA Astrophysics Data System (ADS)

    Zakaznova-Herzog, Valentina P.; Seward, Terry M.

    2012-04-01

    The ionization constants of thioarsenous acid have been determined at 22 °C by measuring the ultraviolet and visible spectra of thioarsenite species in dilute, aqueous sulfide solutions having S/As = 4.18, As = 1.1 × 10-4 mol/dm3 and pH ≈ 6-10.4. No oxidized species such as arsenate, thioarsenate or polysulfides were detected in the experimental solutions. The equilibrium constants for the thioarsenous acid ionization reactions were obtained from a principal component analysis treatment of the spectra and are as follows: H3AsS3=H+H2AsS3- for which pKa1=3.77 (±0.15) H2-AsS32-=H+H2AsS3- for which pKa2=6.53 (±0.08) HAsS32-=H+AsS33- for which pKa3=9.29 (±0.08) The pKa’s for the oxythioarsenous ionization reactions have also been estimated by analogy with those for the end member arsenous and thioarsenous acids. The data emphasize the important role of the simple arsenic(III) thioanions in defining the transport and redox chemistry of arsenic in sulfide-containing natural waters.

  17. A kinetic study of multiple H-attack on methylene blue in aqueous solution

    NASA Astrophysics Data System (ADS)

    Solar, S.; Getoff, N.; Solar, W.; Mark, F.

    The attack of H-atoms on several positions of the methylene blue molecule (5.10 -6-2.10 -5 mol dm -3 MB +) in acid aqueous solution (pH1) was investigated by pulse radiolysis. A least-squares fitting procedure was used for the determination of specific rate constants of these reactions as well as of ɛ-values of the resulting species. It was found that 88% of the H-atoms attacking MB +, with k = (1.2±0.1) × 10 10dm3mol-1s-1, lead to the formation of semiquinone (MBH 22+; SQ), which shows two absorption bands at 400 nm ( ɛ400 = 670 m2mol-1) and 880 nm ( ɛ880 = 1770 m2mol-1) and which decays by dismutation to MB + and leuco dye with 2 k = (2.0±0.3) × 10 9dm3mol-1s-1. 8% of the H-atoms attack the chromophore group with k = (1.1±0.2) × 10 9dm3mol-1s-1, leading to a species (R·) with ɛ400 = 5000 m2mol-1. This unspecified transient disappears probably by a pseudo-first order reaction, with k = (1.4±0.3) × 10 5s-1. The rest of the H-atoms (4%) form H-adducts on the aromatic rings with k(0.6±0.2) × 10 9dm 3mol -1s -1.

  18. Cytogenetic damage in shallot ( Allium cepa) root meristems induced by oil industry "high-density brines".

    PubMed

    Vidaković-Cifrek, Z; Pavlica, M; Regula, I; Papes, D

    2002-10-01

    Saturated water solutions of calcium chloride, calcium bromide (densities 1.30 kg x dm(-3) and 1.61 kg x dm(-3), respectively) and their 1:1 mixture have been commonly used as oil industry "high-density brines." In our experiment they were added to tap water in amounts appropriate to achieve concentrations of 0.025, 0.05, 0.075, and 0.1 mol x dm(-3) to study their cytotoxic effect on the root tip cells of shallot ( Allium cepa L. var. ascalonicum). All tested solutions in concentrations of 0.075 and 0.1 mol x dm(-3) caused significant inhibition of shallot root growth. CaBr (2) showed this effect in concentration 0.05 mol x dm(-3). The investigated solutions in all concentrations applied decreased mitotic activity in root tip cells. The most of mitotic abnormalities were the consequence of spindle failure and chromosome stickiness. Furthermore, the cell microtubules were investigated by indirect immunofluorescence to confirm that most abnormalities observed were the consequence of spindle failure. The present study, as well as previously done Lemna tests and Chlorella tests showed that investigated samples have certain effects on plants, so constant control of their presence in the environment is needed.

  19. One-electron oxidation of mitomycin C and its corresponding peroxyl radicals. A steady-state and pulse radiolysis study

    NASA Astrophysics Data System (ADS)

    Getoff, Nikola; Solar, Sonja; Quint, Ruth M.

    1997-12-01

    The one-electron oxidation of Mitomycin C (MMC) as well as the formation of the corresponding peroxyl radicals were investigated by both steady-state and pulse radiolysis. The steady-state MMC-radiolysis by OH-attack followed at both absorption bands showed different yields: at 218 nm G i (-MMC) = 3.0 and at 364 nm G i (-MMC) = 3.9, indicating the formation of various not yet identified products, among which ammonia was determined, G(NH 3) = 0.81. By means of pulse radiolysis it was established a total κ (OH + MMC) = (5.8 ± 0.2) × 10 9 dm 3 mol -1 s -1. The transient absorption spectrum from the one-electron oxidized MMC showed absorption maxima at 295 nm ( ɛ = 9950 dm 3 mol -1 cm t-1 ), 410 nm ( ɛ = 1450 dm 3 mol -1 cm -1) and 505 nm ( ɛ = 5420 dm 3 mol -1 cm -1). At 280-320 and 505 nm and above they exhibit in the first 150 μs a first order decay, κ1 = (0.85 ± 0.1) × 10 3 s -1, and followed upto ms time range, by a second order decay, 2 κ = (1.3 ± 0.3) × 10 8 dm 3 mol -1 s -1. Around 410 nm the kinetics are rather mixed and could not be resolved. The steady-state MMC-radiolysis in the presence of oxygen featured a proportionality towards the absorbed dose for both MMC-absorption bands, resulting in a G i (-MMC) = 1.5. Among several products ammonia-yield was determined G(NH 3) = 0.52. The formation of MMC-peroxyl radicals was studied by pulse radiolysis, likewise in neutral aqueous solution, but saturated with a gas mixture of 80% N 2O and 20% O 2. The maxima of the observed transient spectrum are slightly shifted compared to that of the one-electron oxidized MMC-species, namely: 290 nm ( ɛ = 10100 dm 3 mol -1 cm -1), 410 nm ( ɛ = 2900 dm 3 mol -1 cm -1) and 520 nm ( ɛ = 5500 dm 3 mol -1 cm -1). The O 2-addition to the MMC-one-electron oxidized transients was found to be at 290 to 410 nm gk(MMC·OH + O 2) = 5 × 10 7 dm 3 mol -1 s -1, around 480 nm κ = 1.6 × 10 8 dm 3 mol -1 s -1 and at 510 nm and above, κ = 3 × 10 8 dm 3 mol -1 s -1. The

  20. Retraction RETRACTION of "Methylation of the RASSFIA promoter in breast cancer" by Y. Ji, H.H. Jin, M.D. Wang, W.X. Cao, J.L. Bao - Genet. Mol. Res. 15 (2): gmr.15028261 (2016) - DOI: 10.4238/gmr.15028261.

    PubMed

    Ji, Y; Jin, H H; Wang, M D; Cao, W X; Bao, J L

    2016-10-07

    The retracted article is: Ji Y, Jin HH, Wang MD, Cao WX, et al. (2016). Methylation of the RASSFIA promoter in breast cancer. Genet. Mol. Res. 15: gmr.15028261. There are significant parts of this article (particularly, in the discussion section) that are copied from "Methylation of HIN-1, RASSF1A, RIL and CDH13 in breast cancer is associated with clinical characteristics, but only RASSF1A methylation is associated with outcome", by Jia Xu, Priya B Shetty, Weiwei Feng, Carol Chenault, Robert C Bast Jr, Jean-Pierre J Issa, Susan G Hilsenbeck and Yinhua Yu, published in BMC Cancer 2012; 12: 243. DOI: 10.1186/1471-2407-12-243. The first paragraphs of both discussions are identical. This is concerning. The abstract and introduction sections have much of their text plagiarized. Overall, there is high plagiarism detected. The GMR editorial staff was alerted and after a thorough investigation, we have strong reason to believe that the peer review process was failure and, after review and contacting the authors, the editors of Genetics and Molecular Research decided to retract the article in accordance with the recommendations of the Committee on Publication Ethics (COPE). The authors and their institutions were advised of this serious breach of ethics.

  1. Retraction RETRACTION of "Efficacy and safety of nucleoside analogues in preventing vertical transmission of the hepatitis B virus from father to infant", by L.-H. Cao, P.-L. Zhao, Z.-M. Liu, S.-C. Sun, D.-B. Xu, J.-D. Zhang and Z.-H. Shao - Genet. Mol. Res. 14 (4): 15539-15546 (2015).

    PubMed

    Cao, L-H; Zhao, P-L; Liu, Z-M; Sun, S-C; Xu, D-B; Zhang, J-D; Shao, Z-H

    2016-10-07

    The retracted article is: Cao L-H, Zhao P-L, Liu Z-M, Sun S-C, et al. (2015). Efficacy and safety of nucleoside analogues in preventing vertical transmission of the hepatitis B virus from father to infant. Genet. Mol. Res. 14: 15539-15546. The article published in Genetics and Molecular Research 14 (4): 15539-15546 (2015) is a very good paper, but it appears that the authors' group submitted this manuscript to multiple journals, which is ethical misconduct. This manuscript (similar language and identical data) was published in the Experimental and Therapeutic Medicine Journal prior to being submitted to GMR. There are parts copied from "Efficacy and safety of nucleoside analogs on blocking father-to-infant vertical transmission of hepatitis B virus", by Li-Hau Cao, Pei-Li Zhao, Zhi-Min Liu, Shao-Chun Sun, et al. Exp. Ther. Med. 9 (6): 2251-2256 (2015) - DOI: 10.3892/etm.2015.2379. The GMR editorial staff was alerted and after a thorough investigation, there is strong reason to believe that the peer review process was failure. Also, after review and contacting the authors, the editors of Genetics and Molecular Research decided to retract this article in accordance with the recommendations of the Committee on Publication Ethics (COPE). The authors and their institutions were advised of this serious breach of ethics.

  2. Retraction RETRACTION of "Tumor necrosis factor alpha gene -308G>A polymorphism association with the risk of esophageal cancer in a Han Chinese population" by H. Zhao, H.W. Zhang, T. Zhang and X.M. Gu - Genet. Mol. Res. 15 (2): gmr.15025866 DOI: http://dx.doi.org/10.4238/gmr.15025866.

    PubMed

    Zhao, H; Zhang, H W; Zhang, T; Gu, X M

    2016-10-07

    The retracted article is: Zhao H, Zhang HW, Zhang T and Gu XM (2016). Tumor necrosis factor alpha gene -308G>A polymorphism association with the risk of esophageal cancer in a Han Chinese population. Genet. Mol. Res. 15: gmr.15025866. Two major concerns were found in this article. Firstly, it was found to be substantially equal to the article "Tumor necrosis factor-alpha gene -308G > A polymorphism alters the risk of hepatocellular carcinoma in a Han Chinese population" published in the Diagnostic Pathology Diagnostic Pathology (2014) 9: 199, by Feng et al.; licensee BioMed Central. 2014 - DOI: 10.1186/s13000-014-0199-3. Secondly, the authors do not discuss limitations of their approaches in the discussion. The discussion is largely an elaboration of the literature in the introduction part. However, even in that context, the discussion does not appropriately review the literature and there are frequent references to conclusions that are not supported by the cited literature. The GMR editorial staff was alerted and after a thorough investigation, there is strong reason to believe that the peer review process was failure. Also, after review and contacting the authors, the editors of Genetics and Molecular Research decided to retract this article in accordance with the recommendations of the Committee on Publication Ethics (COPE). The authors and their institutions were advised of this serious breach of ethics.

  3. Rate coefficients of hydroxyl radical reactions with pesticide molecules and related compounds: A review

    NASA Astrophysics Data System (ADS)

    Wojnárovits, László; Takács, Erzsébet

    2014-03-01

    Rate coefficients published in the literature on hydroxyl radical reactions with pesticides and related compounds are discussed together with the experimental methods and the basic reaction mechanisms. Recommendations are made for the most probable values. Most of the molecules whose rate coefficients are discussed have aromatic ring: their rate coefficients are in the range of 2×109-1×1010 mol-1 dm3 s-1. The rate coefficients show some variation with the electron withdrawing-donating nature of the substituent on the ring. The rate coefficients for triazine pesticides (simazine, atrazine, prometon) are all around 2.5×109 mol-1 dm3 s-1. The values do not show variation with the substituent on the s-triazine ring. The rate coefficients for the non-aromatic molecules which have C=C double bonds or several C-H bonds may also be above 1×109 mol-1 dm3 s-1. However, the values for molecules without C=C double bonds or several C-H bonds are in the 1×107-1×109 mol-1 dm3 s-1 range.

  4. Alkali doped poly (2,5-benzimidazole) membrane for alkaline water electrolysis: Characterization and performance

    NASA Astrophysics Data System (ADS)

    Diaz, Liliana A.; Hnát, Jaromír; Heredia, Nayra; Bruno, Mariano M.; Viva, Federico A.; Paidar, Martin; Corti, Horacio R.; Bouzek, Karel; Abuin, Graciela C.

    2016-04-01

    The properties and performance of linear and cross-linked KOH doped ABPBI membranes as electrolyte/separator for zero gap alkaline water electrolysis cells are evaluated and compared with a commercial Zirfon® diaphragm. Stability in alkaline environment, swelling, thermal properties, water sorption, KOH uptake and conductivity of linear (L-ABPBI) and cross-linked (C-ABPBI) membranes doped with different concentrations of KOH are analyzed. Linear membranes show stability up to 3.0 mol·dm-3 KOH doping, while cross-linked membranes are stable up to 4.2 mol·dm-3 KOH doping. Both kinds of membranes exhibit good thermal stability and reasonable specific ionic conductivity at 22 °C in the range between 7 and 25 mS·cm-1, being slightly higher the conductivity of C-ABPBI membranes than that of L-ABPBI ones. In short-term electrolysis tests both L-ABPBI and C-ABPBI membranes show better performance than Zirfon diaphragm in the range from 50 to 70 °C. A current density of 335 mA·cm-2 at a cell voltage of 2.0 V is attained with C-ABPBI membranes doped in 3 mol·dm-3 KOH at 70 °C, a performance comparable with that of commercial units operating at temperatures ca. 80 °C and 30 wt% KOH (6.7 mol·dm-3) as electrolyte.

  5. The Influence of Diffusion Fluxes on the Detection Limit of the Jalpaite Copper Ion-Selective Electrode

    DTIC Science & Technology

    2001-10-02

    Jasinski Nernstian response down to 10-12 mol dm- 3 Pb for a et al. [14] along with Smith and Manahan [15] in the early galvanostatically controlled...Smith, S. E. Manahan , Anal. Chem. 1973, 45, 836. [26] R. De Marco, R. Eriksen. A. Zirino, Anal. Chern. 1998, 70, [16] T. Sokalski, A. Ceresa, T

  6. Poly-Alizarin red S/multiwalled carbon nanotube modified glassy carbon electrode for the boost up of electrocatalytic activity towards the investigation of dopamine and simultaneous resolution in the presence of 5-HT: A voltammetric study.

    PubMed

    Reddaiah, K; Madhusudana Reddy, T; Venkata Ramana, D K; Subba Rao, Y

    2016-05-01

    Poly-Alizarin red S/multiwalled carbon nanotube film on the surface of glassy carbon electrode (poly-AzrS/MWCNT/GCE) was synthesized by electrochemical process and was used for the sensitive and selective determination of dopamine (DA) by employing voltammetric techniques. The electrocatalytic response of the modified electrode was found to exhibit admirable activity. The simultaneous determination of dopamine in the presence of serotonin (5-HT) was found to exhibit very good response at poly-AzrS/MWCNTs/GCE. The effect of pH, scan rate, accumulation time and concentration of dopamine was studied at the developed poly-AzrS/MWCNTs/GCE. The poly-AzrS/MWCNTs/GCE exhibited an efficient electron mediating behavior together with well resolved peaks for dopamine, in 0.1 mol/dm(3) phosphate buffer (PBS) solution of pH 7.0. The limit of detection (LOD) and limit of quantification (LOQ) were found to be as 1.89 × 10(-7) mol/dm(3) and 6.312 × 10(-7) mol/dm(3) respectively with a dynamic range from 1 × 10(-6) to 1.8 × 10(-5) mol/dm(3). The interfacial electron transfer behavior of DA was studied by electrochemical impedance spectroscopy (EIS); the studies showed that the charge transfer rate was enhanced at poly-AzrS/MWCNTs/GCE when compared with bare GCE and poly-AzrS/GCE.

  7. Malonic acid concentration as a control parameter in the kinetic analysis of the Belousov-Zhabotinsky reaction under batch conditions.

    PubMed

    Blagojević, Slavica M; Anić, Slobodan R; Cupić, Zeljko D; Pejić, Natasa D; Kolar-Anić, Ljiljana Z

    2008-11-28

    The influence of the initial malonic acid concentration [MA]0 (8.00 x 10(-3) < or = [MA]0 < or = 4.30 x 10(-2) mol dm(-3)) in the presence of bromate (6.20 x 10(-2) mol dm(-3)), bromide (1.50 x 10(-5) mol dm(-3)), sulfuric acid (1.00 mol dm(-3)) and cerium sulfate (2.50 x 10(-3) mol dm(-3)) on the dynamics and the kinetics of the Belousov-Zhabotinsky (BZ) reactions was examined under batch conditions at 30.0 degrees C. The kinetics of the BZ reaction was analyzed by the earlier proposed method convenient for the examinations of the oscillatory reactions. In the defined region of parameters where oscillograms with only large-amplitude relaxation oscillations appeared, the pseudo-first order of the overall malonic acid decomposition with a corresponding rate constant of 2.14 x 10(-2) min(-1) was established. The numerical results on the dynamics and kinetics of the BZ reaction, carried out by the known skeleton model including the Br2O species, were in good agreement with the experimental ones. The already found saddle node infinite period (SNIPER) bifurcation point in transition from a stable quasi-steady state to periodic orbits and vice versa is confirmed by both experimental and numerical investigations of the system under consideration. Namely, the large-amplitude relaxation oscillations with increasing periods between oscillations in approaching the bifurcation points at the beginning and the end of the oscillatory domain, together with excitability of the stable quasi-steady states in their vicinity are obtained.

  8. 22 CFR 19.10-4 - Death or divorce of a spouse and remarriage after retirement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Death or divorce of a spouse and remarriage...-4 Death or divorce of a spouse and remarriage after retirement. (a) If the marriage of an annuitant... spouse is dissolved by divorce or by death of the spouse, the retiree's annuity shall be recomputed,...

  9. 22 CFR 19.10-4 - Death or divorce of a spouse and remarriage after retirement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Death or divorce of a spouse and remarriage...-4 Death or divorce of a spouse and remarriage after retirement. (a) If the marriage of an annuitant... spouse is dissolved by divorce or by death of the spouse, the retiree's annuity shall be recomputed,...

  10. 22 CFR 19.10-4 - Death or divorce of a spouse and remarriage after retirement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Death or divorce of a spouse and remarriage...-4 Death or divorce of a spouse and remarriage after retirement. (a) If the marriage of an annuitant... spouse is dissolved by divorce or by death of the spouse, the retiree's annuity shall be recomputed,...

  11. 22 CFR 19.10-4 - Death or divorce of a spouse and remarriage after retirement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Death or divorce of a spouse and remarriage...-4 Death or divorce of a spouse and remarriage after retirement. (a) If the marriage of an annuitant... spouse is dissolved by divorce or by death of the spouse, the retiree's annuity shall be recomputed,...

  12. 22 CFR 19.10-4 - Death or divorce of a spouse and remarriage after retirement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Death or divorce of a spouse and remarriage...-4 Death or divorce of a spouse and remarriage after retirement. (a) If the marriage of an annuitant... spouse is dissolved by divorce or by death of the spouse, the retiree's annuity shall be recomputed,...

  13. Financial services FY 1996 site support program plan, WBS 6.10.4. Revision 1

    SciTech Connect

    Schafer, D.D.

    1995-09-01

    This program plan outlines the financial services to be provided to the Hanford reservation by the Westinghouse Hanford Company. The topics of the plan include the Hanford strategic plan, program mission, program strategy, technical requirements baseline, schedule baseline, cost baseline, performance measures, technical objectives, program performance and program funding required.

  14. Detail design of a 10.4-m stretched-membrane dish. Phase 2, Final report

    SciTech Connect

    Not Available

    1994-01-01

    This report describes efforts conducted under Tasks 3 and 4 of the second phase of the project to develop a single-element stretched-membrane dish concept to reduce the cost of a high-performance concentrating solar collector. We completed the detailed design for such a collector suitable to drive a 25-kWe Stirling motor generator. The design includes the collectors, optical element, the drive, and support systems. The aperture of the optical element was sized to provide the required energy to the engine based on test data and analytical models of the concentrator receiver, and engine. The design of the optical element was improved based on experience gained from the design, fabrication, and testing of several prototypes.

  15. Interaction of cinnamic acid derivatives with serum albumins: A fluorescence spectroscopic study

    NASA Astrophysics Data System (ADS)

    Singh, T. Sanjoy; Mitra, Sivaprasad

    2011-03-01

    Cinnamic acid (CA) derivatives are known to possess broad therapeutic applications including anti-tumor activity. The present study was designed to determine the underlying mechanism and thermodynamic parameters for the binding of two CA based intramolecular charge transfer (ICT) fluorescent probes, namely, 4-(dimethylamino) cinnamic acid (DMACA) and trans-ethyl p-(dimethylamino) cinnamate (EDAC), with albumins by fluorescence spectroscopy. Stern-Volmer analysis of the tryptophan fluorescence quenching data in presence of the added ligand reveals fluorescence quenching constant ( κq), Stern-Volmer constant ( KSV) and also the ligand-protein association constant ( Ka). The thermodynamic parameters like enthalpy (Δ H) and entropy (Δ S) change corresponding to the ligand binding process were also estimated. The results show that the ligands bind into the sub-domain IIA of the proteins in 1:1 stoichiometry with an apparent binding constant value in the range of 10 4 dm 3 mol -1. In both the cases, the spontaneous ligand binding to the proteins occur through entropy driven mechanism, although the interaction of DMACA is relatively stronger in comparison with EDAC. The temperature dependence of the binding constant indicates the induced change in protein secondary structure.

  16. Adsorption mechanisms of RNA mononucleotides on silver nanoparticles.

    PubMed

    Miljanić, Snežana; Dijanošić, Adriana; Matić, Ivona

    2015-02-25

    Surface-enhanced Raman scattering (SERS) of four RNA mononucleotides (AMP, GMP, CMP and UMP) has been studied on the citrate-reduced silver colloid aggregated with sodium sulfate. Concentration dependent spectra in the range of 1×10(-7)-1×10(-4) mol dm(-3) were obtained, assigned and interpreted according to the surface selection rules. For purine mononucleotides, AMP and GMP, adsorption onto the silver nanoparticles through the six-membered ring of the nitrogenous base was suggested. Concentration dependent splitting of the ring breathing band in the spectra of AMP indicated coexistence of two species on the silver surface, which differed in contribution of the adenine N1 atom and the exocyclic NH2 group in binding. Unlike the AMP spectra, the spectra of GMP implied only one mode of adsorption of the molecules onto the silver nanoparticles, taking place through the guanine N1H and C=O group. Weak SERS spectra of pyrimidine mononucleotides, CMP and UMP, pointed to involvement of carbonyl oxygen in adsorption process, whereby the molecules adopted the position on the nanoparticles with ribose close to the metal surface. Intense bands in the low wavenumber region, associated with stretching of the formed Ag-N and/or Ag-O bonds, supported chemical binding of the RNA mononucleotides with the silver surface.

  17. Charging of silver bromide aqueous interface: evaluation of interfacial equilibrium constants from surface potential data.

    PubMed

    Preočanin, Tajana; Supljika, Filip; Kallay, Nikola

    2010-06-01

    A single crystal silver bromide electrode (SCr-AgBr) was used to measure the inner surface potential (Ψ(0)) at the silver bromide aqueous electrolyte interface as a function of the activities of Br(-) and Ag(+). Absolute values of the surface potential were calculated from electrode potentials of SCr-AgBr using the value of point of zero charge (pBr(pzc)=6.9 [H.A. Hoyen, R.M. Cole, J. Colloid Interface Sci. 41 (1972) 93.]) as the value of point of zero potential. Measurements were performed in potassium nitrate aqueous solutions. The Ψ(0)(pBr) function was linear and slightly dependent on the ionic strength. The reduction values of the slope with respect to the Nernst equation, expressed by the α coefficient, were 0.880,0.935, and 0.950 at ionic strengths of 10(-4), 10(-3), and 10(-2) mol dm(-3), respectively. The results were successfully interpreted by employing the surface complexation model, developed originally for metal oxides and adapted for silver halides. The thermodynamic ("intrinsic") equilibrium constants for binding of bromide (K(n)(∘)) and silver (K(p)(∘)) ions on the corresponding sites at the silver bromide surface were evaluated as lgK(n)(∘)=3.98; lgK(p)(∘)=2.48. Symmetrical counterion surface association was assumed and equilibrium constants were obtained as lgK(NO(3)(-))(∘)=lgK(K(+))(∘)=4.30.

  18. Exploring the biophysical aspects and binding mechanism of thionine with bovine hemoglobin by optical spectroscopic and molecular docking methods.

    PubMed

    Shanmugaraj, Krishnamoorthy; Anandakumar, Shanmugam; Ilanchelian, Malaichamy

    2014-02-05

    In the present investigation, we have elucidated the interaction between thionine (TH) and bovine hemoglobin (BHb) under physiological conditions by using absorption, emission, time resolved fluorescence, synchronous fluorescence, circular dichroism (CD) and three dimensional emission (3D) spectral studies. Molecular docking experiment was also carried out to establish the possible binding site of TH on BHb. The emission spectral studies revealed that, TH have the ability to bind with BHb and form a ground state complex via static quenching process. The calculated binding constant and the number of binding sites was found to be 3.65×10(4)dm(3)mol(-1) and 1.04, respectively. Förster Resonance Energy Transfer (FRET) theory was employed to calculate the distance (r) between donor (BHb) and acceptor (TH) as 3.64nm. Furthermore, the conformational changes of BHb induced by TH complexation showed some degree of structural unfolding. In addition, molecular docking study confirmed that the most probable binding site of TH was located within the active cavity constituted by α1 and α2 subunits of BHb.

  19. Growth of different morphologies (quantum dots to nanorod) of Ag-nanoparticles: role of cysteine concentrations.

    PubMed

    Khan, Zaheer; Talib, Abou

    2010-03-01

    This work describes an easy chemical method for the preparation of orange-red color silver sol by the cysteine reduction of silver (I) in the presence of cetyltrimethylammonium bromide (CTAB). The obtained sol was found to have very small particles in the order of quantum dots for the first time. Transmission electron microscope (TEM) images show that the silver sol consists of aggregated as well as cross-linking arrangement of spherical silver quantum dots (size in the range ca. or=20.0x10(-4)mol dm(-3)), white precipitate was formed instead of transparent silver sol. Cysteine acts as a reducing, cross-linking, stabilizing and buffering agent during the growth of different shape and size of silver nanoparticles.

  20. Cysteine as a green corrosion inhibitor for Cu37Zn brass in neutral and weakly alkaline sulphate solutions.

    PubMed

    Radovanović, Milan B; Petrović, Marija B; Simonović, Ana T; Milić, Snežana M; Antonijević, Milan M

    2013-07-01

    The aim of this study was to investigate electrochemical properties of brass in neutral and weakly alkaline solutions in the presence of cysteine as a nontoxic and ecological corrosion inhibitor. Potentiodynamic measurements, open circuit potential measurements, as well as chronoamperometric measurements were the methods used during investigation of the inhibitory effect of cysteine on the corrosion behaviour of brass. Potentiodynamic measurements showed that cysteine behaves as a mixed-type inhibitor in the investigated media. Based on polarization curves for brass in a weakly alkaline solution of sodium sulphate at varying cysteine concentrations, an interaction occurs between Cu(+) ions and the inhibitor, resulting in the formation of a protective complex on the electrode surface. The results of chronoamperometric measurements confirm the results obtained by potentiodynamic measurements. Optical microphotography of the brass surface also confirms the formation of a protective film in the presence of a 1 × 10(-4) mol/dm(3) cysteine. Adsorption of cysteine on the brass surface proceeds according to the Langmuir adsorption isotherm.

  1. A mixture of triethylphosphate and ethylene carbonate as a safe additive for ionic liquid-based electrolytes of lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Lalia, Boor Singh; Yoshimoto, Nobuko; Egashira, Minato; Morita, Masayuki

    A binary mixture of triethylphosphate (TEP) and ethylene carbonate (EC) has been examined as a new non-flammable additive for ionic liquid-based electrolytes for lithium-ion batteries. The optimized electrolyte composition consists of 0.6 mol dm -3 (=M) LiTFSI in PP13TFSI mixed with TEP and EC in volume ratio of 80:10:10, where TFSI and PP13 denote bis(trifluoromethanesulfonyl)imide and N-methyl- N-propylpiperidinium, respectively. The ionic conductivity of PP13TFSI dissolving 0.4 M LiTFSI was improved from 8.2 × 10 -4 S cm -1 to 3.5 × 10 -3 S cm -1 (at 20 °C) with the addition of TEP and EC. The electrochemical behavior of 0.4 M LiTFSI/PP13TFSI with and without TEP and EC was studied by cyclic voltammetry, which showed no deteriorating effect by the addition of TEP and EC on the electrochemical window of PP13TFSI. The flammability of the electrolyte was tested by a direct flame test. The proposed ionic liquid-based electrolyte revealed significant improvements in the electrochemical charge-discharge characteristics for both graphite negative and LiMn 2O 4 positive electrodes.

  2. Supramolecular effects and molecular discrimination by macrocyclic hosts embedded in synthetic bilayer membranes.

    PubMed Central

    Murakami, Y; Hayashida, O

    1993-01-01

    Hybrid assemblies were prepared in combinations of a synthetic lipid, involving an L-alanine residue interposed between an anionic head group and a hydrophobic double-chain segment, with cage-type cyclophanes having a three-dimensionally extended hydrophobic cavity. Incorporation behavior of the cage-type hosts into the multi- and single-walled vesicules was characterized by highly sensitive differential scanning calorimetry and dynamic light-scattering measurements as well as by gel-filtration chromatography and electronic absorption spectroscopy. Both hosts were found to be completely incorporated into a relatively polar domain close to the vesicular surface. Anionic guest molecules, such as naphthol yellow S, dimethylsulfonazo III, bromopyrogallol red, and orange G, were effectively incorporated into the hydrophobic cavities provided by the cage-type cyclophanes embedded in the single-walled bilayer membrane, as confirmed by circular dichroism spectroscopy; the formation constants for 1:1 host-guest complexes were in the order of 10(4)-10(5) mol.dm-3. This means that the binding affinities of the cage-type hosts are largely retained even when the hosts are incorporated into the vesicle. Moreover, the pyridinium moieties bound to the chiral L-valine residues in the bridging components of the hosts underwent conformational changes upon inclusion of the guest, as confirmed by circular dichroism spectroscopy and molecular mechanics and dynamics calculations. Images PMID:8433975

  3. Reduction of the copper ion to its metal and clusters in alcoholic media: A radiation chemical study

    NASA Astrophysics Data System (ADS)

    Dey, G. R.

    2005-10-01

    Reduction of Cu 2+ ions with and without I - as a ligand was studied in N 2-purged alcoholic solutions by pulse radiolysis. In the absence of iodide ion, the initial rate constant for e -sol reaction with Cu 2+ was determined following the decay of solvated electrons in different alcohols; kbimol values are in the range of 0.8-1.1×10 10 dm 3 mol -1 s -1. In the presence of 10 -3 mol dm -3 KI, the respective kbimol remained almost same. Generally, on reduction, Cu(II) ion changes to Cu(I) ion initially and later it produces metallic copper (Cu°), and the stability of these intermediates depends on the conditions of the matrix. In the presence of I -, Copper ions such as Cu(II) or Cu(I) ions get reduced to metallic copper (Cu°) having initial absorption around 740 and below 400 nm. Later, at 100 μs time after the electron pulse, it gets transformed into a nanoparticle with an absorption band at 580 nm. Such formation of copper nanoparticle was observed only in 2-propanolic medium in the presence of iodide ions. During γ-radiolysis of N 2-purged 1.5×10 -4 CuSO 4 solutions in 2-propanol, reddish pink colored copper nanoparticles were formed, which are quite similar to those reported earlier in aqueous solution. But, in the presence of I - (2-propanolic solutions), such phenomenon was not noticed on γ-radiolysis. Interestingly, the formation of copper nanoparticle was observed also in the reactions of copper (II) ions with alcohol radicals formed during γ-radiolysis in N 2O-purged system, where e -sol were scavenged by N 2O. The nanoparticles generated both in N 2 and N 2O-purged alcoholic systems, viz. methanol, ethanol and 2-propanol, were found to be oxygen sensitive. The contradictory results from pulse and γ-radiolysis studies in the presence and absence of iodide ions are explained to account for the nanoparticle generation.

  4. Equilibrium studies of copper ion adsorption onto palm kernel fibre.

    PubMed

    Ofomaja, Augustine E

    2010-07-01

    The equilibrium sorption of copper ions from aqueous solution using a new adsorbent, palm kernel fibre, has been studied. Palm kernel fibre is obtained in large amounts as a waste product of palm oil production. Batch equilibrium studies were carried out and system variables such as solution pH, sorbent dose, and sorption temperature were varied. The equilibrium sorption data was then analyzed using the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherms. The fit of these isotherm models to the equilibrium sorption data was determined, using the linear coefficient of determination, r(2), and the non-linear Chi-square, chi(2) error analysis. The results revealed that sorption was pH dependent and increased with increasing solution pH above the pH(PZC) of the palm kernel fibre with an optimum dose of 10g/dm(3). The equilibrium data were found to fit the Langmuir isotherm model best, with a monolayer capacity of 3.17 x 10(-4)mol/g at 339K. The sorption equilibrium constant, K(a), increased with increasing temperature, indicating that bond strength between sorbate and sorbent increased with temperature and sorption was endothermic. This was confirmed by the increase in the values of the Temkin isotherm constant, B(1), with increasing temperature. The Dubinin-Radushkevich (D-R) isotherm parameter, free energy, E, was in the range of 15.7-16.7kJ/mol suggesting that the sorption mechanism was ion exchange. Desorption studies showed that a high percentage of the copper was desorbed from the adsorbent using acid solutions (HCl, HNO(3) and CH(3)COOH) and the desorption percentage increased with acid concentration. The thermodynamics of the copper ions/palm kernel fibre system indicate that the process is spontaneous and endothermic.

  5. Removal of nickel(II) ions from aqueous solutions using the natural clinoptilolite and preparation of nano-NiO on the exhausted clinoptilolite

    NASA Astrophysics Data System (ADS)

    Rajic, Nevenka; Stojakovic, Djordje; Jovanovic, Mina; Logar, Natasa Zabukovec; Mazaj, Matjaz; Kaucic, Venceslav

    2010-12-01

    The natural zeolite tuff (clinoptilolite) from a Serbian deposit has been studied as adsorbent for Ni(II) ions from aqueous solutions. Its sorption capacity at 298 K varies from 1.9 mg Ni g -1 (for the initial solution concentration of 100 mg Ni dm -3) to 3.8 mg Ni g -1 (for C0 = 600 mg Ni dm -3) and it increases 3 times at 338 K. The sorption is best described by the Sips isotherm model. The sorption kinetics follows the pseudo-second-order model, the activation energies being 7.44, 5.86, 6.62 and 6.63 kJ mol -1 for C0 = 100, 200, 300 and 400 mg Ni dm -3, respectively. The sorption involves a film diffusion, an intra-particle diffusion, and a chemical cation-exchange between the Na + ions of clinoptilolite and the Ni 2+ ions. The sorption is endothermic (Δ H° being 37.9, 33.4, 30.0, 27.7 and 24.3 kJ mol -1 for C0 = 100, 200, 300, 400 and 600 mg Ni dm -3, respectively) and spontaneous in the 298-338 K temperature range. Thermal treatment of the Ni(II)-loaded clinoptilolite results in the formation of spherical nano-NiO particles of approx. 5 nm in diameter which are randomly dispersed in the clinoptilolite lattice.

  6. Synthesis, complexation and water exchange properties of Gd(III)-TTDA-mono and bis(amide) derivatives and their binding affinity to human serum albumin.

    PubMed

    Ou, Ming-Hung; Chen, Yi-Ming; Chang, Ya-Hui; Lu, Wen-Kuei; Liu, Gin-Chung; Wang, Yun-Ming

    2007-07-14

    With the objective of tuning the lipophilicity of ligands and maintaining the neutrality and stability of Gd(III) chelate, we designed and synthesized two bis(amide) derivatives of TTDA, TTDA-BMA and TTDA-BBA, and a mono(amide) derivative, TTDA-N-MOBA. The ligand protonation constants and complex stability constants for various metal ions were determined in this study. The identification of the microscopic sites of protonation of the amide ligand by 1H NMR titrations show that the first protonation site occurs on the central nitrogen atom. The values of the stability constant of TTDA-mono and bis(amide) complex are significantly lower than those of TTDA and DTPA, but the selectivity constants of these ligands for Gd(III) over Zn(II) and Cu(II) are slightly higher than those of TTDA and DTPA. On the basis of the water-exchange rate values available for [Gd(TTDA-BMA)(H2O)], [Gd(TTDA-BBA)(H2O)] and [Gd(TTDA-N-MOBA)(H2O)]-, we can state that, in general, the replacement of one carboxylate group by an amide group decreases the water-exchange rate of the gadolinium(III) complexes by a factor of about three to five. The decrease in the exchange rate is explained in terms of a decreased steric crowding and charge effect around the metal ion when carboxylates are replaced by an amide group. In addition, to support the HSA protein binding studies of lipophilic [Gd(TTDA-N-MOBA)(H2O)]- and [Gd(TTDA-BBA)(H2O)] complexes, further protein-complex binding was studied by ultrafiltration and relaxivity studies. The binding constants (KA) of [Gd(TTDA-N-MOBA)(H2O)]- and [Gd(TTDA-BBA)(H2O)] are 8.6 x 10(2) and 1.0 x 10(4) dm3 mol(-1), respectively. The bound relaxivities (r1(b)) are 51.8 and 52 dm3 mmol(-1) s(-1), respectively. The KA value of [Gd(TTDA-BBA)(H2O)] is similar to that of MS-325 and indicates a stronger interaction of [Gd(TTDA-BBA)(H2O)] with HSA.

  7. Thermodynamics for complex formation between palladium(ii) and oxalate.

    PubMed

    Pilný, Radomír; Lubal, Přemysl; Elding, Lars I

    2014-08-28

    Complex formation between [Pd(H2O)4](2+) and oxalate (ox = C2O4(2-)) has been studied spectrophoto-metrically in aqueous solution at variable temperature, ionic strength and pH. Thermodynamic parameters at 298.2 K and 1.00 mol dm(-3) HClO4 ionic medium for the complex formation [Pd(H2O)4](2+) + H2ox ⇄ [Pd(H2O)2(ox)] + 2H3O(+) with equilibrium constant K1,H (in mol dm(-3)) are log10K1,H = 3.38 ± 0.08, ΔH = -33 ± 3 kJ mol(-1), and ΔS = -48 ± 11 J K(-1) mol(-1), as determined from spectrophotometric equilibrium titrations at 15.0, 20.0, 25.0 and 31.0 °C. Thermodynamic overall stability constants β (in (mol dm(-3))(-n), n = 1,2) for [Pd(H2O)2(ox)] and [Pd(ox)2](2-) at zero ionic strength and 298.2 K, defined as the equilibrium constants for the reaction Pd(2+) + nox(2-) ⇄ [Pd(ox)n](2-2n) (water molecules omitted) are log10β = 9.04 ± 0.06 and log10β = 13.1 ± 0.3, respectively, calculated by use of Specific Ion Interaction Theory from spectrophotometric titrations with initial hydrogen ion concentrations of 1.00, 0.100 and 0.0100 mol dm(-3) and ionic strengths of 1.00, 2.00 or 3.00 mol dm(-3). The values derived together with literature data give estimated overall stability constants for Pd(ii) compounds such as [Pd(en)(ox)] and cis-[Pd(NH3)2Cl2], some of them analogs to Pt(ii) complexes used in cancer treatment. The palladium oxalato complexes are significantly more stable than palladium(ii) complexes with monodentate O-bonding ligands. A comparison between several different palladium complexes shows that different parameters contribute to the stability variations observed. These are discussed together with the so-called chelate effect.

  8. Cathodic adsorptive stripping voltammetric determination of uranium with potassium hydrogen phthalate.

    PubMed

    Farghaly, O A; Ghandour, M A

    1999-06-01

    The adsorption properties of dioxouranium (II)-Phathalate complexes onto hanging mercury drop electrode are exploited in developing a highly sensitive and selective stripping voltammetric procedure for the determination of uranium (VI). The reduction current of adsorbed complex ions of U(VI) was measured by both linear sweep (LSCSV) and differential pulse cathodic stripping voltammetry (DPCSV), preceded by a period of preconcentration onto the electrode surface. As low as 2x10(-9) mol dm(-3) (0.5 mug/l) and 2x10(-8) mol dm(-3) (4.8 mug/l) with accumulation time 240 and 120 s using DPCSV and LSCSV, respectively, have been determined successfully. The relative standard deviation of 2.2% at the 5 ppm level was obtained. The interferences of some metal ions and anions were studied. The application of this method was tested in the determination of uranium in superphosphate fertilizer.

  9. Decomposition of persistent pharmaceuticals in wastewater by ionizing radiation

    NASA Astrophysics Data System (ADS)

    Kimura, Atsushi; Osawa, Misako; Taguchi, Mitsumasa

    2012-09-01

    Pharmaceuticals in wastewater were treated by the combined method of activated sludge and ionizing radiation in laboratory scale. Oseltamivir, aspirin, and ibuprofen at 5 μmol dm-3 in wastewater were decomposed by the activated sludge at reaction time for 4 h. Carbamazepine, ketoprofen, mefenamic acid, clofibric acid, and diclofenac were not biodegraded completely, but were eliminated by γ-ray irradiation at 2 kGy. The rate constants of the reactions of these pharmaceuticals with hydroxyl radicals were estimated by the competition reaction method to be 4.0-10×109 mol-1 dm3 s-1. Decompositions of the pharmaceuticals in wastewater by ionizing radiation were simulated by use of the rate constants and the amount of total organic carbon as parameters. Simulation curves of concentrations of these pharmaceuticals as a function of dose described the experimental data, and the required dose for the elimination of them in wastewater by ionizing radiation can be estimated by this simulation.

  10. Oxidation of naringenin by gamma-radiation

    NASA Astrophysics Data System (ADS)

    Nagy, Tristan O.; Ledolter, Karin; Solar, Sonja

    2008-06-01

    The reaction of rad OH with naringenin (4',5,7-trihydroxyflavanone) in the presence of air induced the formation of the hydroxylation product eriodictyol (3',4',5,7-tetrahydroxyflavanone). Its yield was dependent on pH. The initial degradation yield of naringenin was Gi(-Nar)=(2.5±0.2)×10 -7 mol dm -3 J -1. For the reaction with rad OH, a rate constant k ( rad OH+naringenin)=(7.2±0.7)×10 9 M -1 s -1 was determined. In the presence of N 2O and NaN 3/N 2O, no eriodyctiol was formed. Apigenin (4',5,7-trihydroxyflavon) was detected as decay product of the naringenin phenoxyl radicals. In Ar-saturated solutions, naringenin exhibited a pronounced radiation resistance, G(-naringenin) ˜0.3×10 -7 mol dm -3 J -1.

  11. Direct rate constant measurement of radical disulphide anion formation for cysteine and cysteamine in aqueous solution

    NASA Astrophysics Data System (ADS)

    Mezyk, Stephen P.

    1995-03-01

    The techniques of pulse radiolysis, laser photolysis and absorption spectroscopy have been used to directly determine rate constants for radical disulphide anion formation for cysteine and cysteamine in aqueous solution. The measured values for cysteine, over the pH range 7-12, allowed calculation of individual rate constants for the constituent reactions RS . + RSH → RSSR -. + H + and RS . + RS - → RSSR -. as (3.39 ± 0.31) × 10 8 and (1.21 ± 0.04) × 10 9 dm 3 mol -1 s -1, respectively. Analogous values for cysteamine were also determined by this technique as (3.06 ± 0.16) × 10 8 and (3.65 ± 0.07) × 10 9 dm 3 mol -1 s -1.

  12. Structure and Dynamics of Solutions of Lithium Salts Relevant to Battery Construction.

    DTIC Science & Technology

    1988-01-01

    00_T Sc. ADDRESS (City, State, and ZIP Code) 10 . SOURCE OF FUNDING NUMBERS P. 0. Box 12211 PROGRAM 1 PROJECT TASK WORK UNIT Research Triangle Park, NC...electrolytes may be employed at low temperature either in stratospheric conditions (missiles) or subarctic conditions (GI’s in the field). 88 5 10 045 Page...concentration c< 10 mol/dm3 ). We then derived a theory of activity coefficients based on dipole-dipole potentials which reproduces satisfactorily the activity

  13. Environmental study of two significant solid samples: gravitation dust sediment and soil.

    PubMed

    Remeteiová, Dagmar; Rusnák, Radoslav; Kucanová, Eva; Fióová, Beáta; Ružičková, Silvia; Fekete, Ilona; Horváth, Márk; Dirner, Vojtech

    2012-01-01

    In this work are presented results of the complex study of two significant solid environmental samples: gravitation dust sediments (industrial pollutants, potential source of risk elements input to soils) and soils (component of the environment, potential source of risk elements input to food web). The first phase of this study was focused on the study of the significant chemical properties (phase composition, content of organic and inorganic carbon) of the dust and soil samples. In the second phase, the fractionation analysis was used on the evaluation of the mobility of chosen risk elements (Cu, Ni, Pb, Zn) in the studied samples. The single-step extractions were applied in the order of the isolation of the element forms (fractions), with different mobilities during defined ecological conditions by utilization of the following reagents: 1 mol dm(-3) NH(4)NO(3) for isolation of the "mobile" fraction, 0.05 mol dm(-3) ethylenediaminetetraacetic acid and 0.43 mol dm(-3) CH(3)COOH for isolation of the "mobilizable" fraction, and 2 mol dm(-3) HNO(3) for isolation of all releasable forms. On the basis of the results obtained in this study, it is possible to state that different origins and positions of solid environmental samples in the environment reflect in different chemical properties of their matrix. The different properties of the sample matrix result in different mobilities of risk elements in these kinds of samples. The fractionation analysis with single-step extraction for isolation element fractions is the method most suitable for easy checking of environmental pollution and for evaluation of risk elements cycle in the environment.

  14. OH-radical induced degradation of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 4-chloro-2-methylphenoxyacetic acid (MCPA): A pulse radiolysis and gamma-radiolysis study

    NASA Astrophysics Data System (ADS)

    Zona, Robert; Solar, Sonja; Sehested, Knud

    2012-02-01

    The reactions of rad OH, H rad and e aq- with 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 4-chloro-2-methylphenoxyacetic acid (MCPA) were studied by pulse radiolysis. The site of rad OH-radicals addition to the aromatic ring of 2,4,5-T was found to be—C1: ˜18%, C2/C4/C5: total ˜28% and C3/C6: total ˜41%. The overall rate constants with OH-radicals were k( rad OH+2,4,5-T)=6.4 (±0.5)×10 9 mol dm -3 s -1 and k( rad OH+MCPA)=8.5 (±0.8)×10 9 mol dm -3 s -1. The radiation induced decomposition of the pesticides, chloride- and product formation (phenolic compounds, aliphatic acids) was studied by gamma radiolysis as a function of dose. A mechanism for acetate formation is discussed. The presence of oxygen during irradiation affected the decomposition rate only indiscernibly, however, chloride elimination, ring fragmentation (formation of aliphatic acids), TOC- and toxicity reduction were strongly enhanced. For complete removal of 500 μmol dm -3 herbicides a dose of ˜4 kGy was required. Using air saturation during irradiation a reduction of 37-40% of the TOC was observable at 5 kGy, detoxification (luminescence inhibition <20%) was achieved with 10 kGy.

  15. Ionic association of hydroperoxide anion HO2- in the binding mean spherical approximation. Spectroscopic study of hydrogen peroxide in concentrated sodium hydroxide solutions.

    PubMed

    Chlistunoff, Jerzy; Simonin, Jean-Pierre

    2006-12-28

    The ultraviolet-visible (UV-vis) spectroscopy of hydrogen peroxide in concentrated sodium hydroxide solutions was studied. The peroxide band in the UV range shifts from approximately 214 nm to approximately 236 nm as the NaOH concentration increases from 0.338 mol dm-3 to 13.1 mol dm-3. The band originates from an intramolecular electronic transition of the hydroperoxide anion HO2-, as indicated by the negligible temperature effect on the band position and confirmed by ab initio quantum mechanical calculations. It is postulated that the bathochromic shift of the peroxide band that accompanies the increase in NaOH concentration originates from the formation of the ion pair (Na+HO2-). The equilibrium constant for the ion association reaction (0.048 mol-1 dm3) and the characteristics of the individual absorption bands of the hydroperoxide anion and its associate with Na+ were determined from the numerical modeling of the absorbance data, using the binding mean spherical approximation (BIMSA).

  16. Formation and reactivity of carboxyphenyl radicals in aqueous solution

    NASA Astrophysics Data System (ADS)

    Janković, Ivana A.; Josimović, Ljubica R.; Jovanović, Slobodan V.

    1998-03-01

    Carboxyphenyl radicals were generated in aqueous solutions by reacting the solvated electron with ortho-, meta- and para-chlorobenzoate. These radicals were found to add to chlorobenzoates and abstract hydrogen atoms from a H-atom donor. It was concluded that the rate constants for the addition of carboxyphenyl radicals to chlorobenzoate depend on steric hindrance, since ortho-carboxyphenyl radical adds to 2-chlorobenzoate [ kadd=(1.0±0.2)×10 6 dm 3 mol -1 s -1] an order of magnitude slower than para-carboxyphenyl radical to 4-chlorobenzoate [ kadd=(1.0±0.2)×10 7 dm 3 mol -1 s -1]. The products of these addition reactions were detected by GC-MS. All three carboxyphenyl radical isomers abstract a H-atom from 4-methoxybenzen thiol at the same rate [ kH-aps˜1×10 9 dm 3 mol -1 s -1], i.e. the position of the carboxylate group seems not to influence the rate of the H-abstraction reaction.

  17. VizieR Online Data Catalog: ExoMol. XVII: SO3 (Underwood+, 2016)

    NASA Astrophysics Data System (ADS)

    Underwood, D. S.; Yurchenko, S. N.; Tennyson, J.; Al-Refaie, A. F.; Clausen, S.; Fateev, A.

    2017-01-01

    Because of their size, the transitions are listed in 500 separate files, each containing all the transitions in a 10cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the highest frequency in the range; thus the a-4690.dat file contains all the transitions of SO3 in the frequency range 4680-4690cm-1 but not including 4680cm-1. The transition files a-xxxx.dat contain three columns: the reference number in the energy file of the upper state, that of the lower state and the Einstein A coefficient of the transition. The energy file and the transitions files are bzipped, and need to be extracted before use. We also provide the partition functions for each molecule in the range 0 to 1000K. (3 data files).

  18. VizieR Online Data Catalog: Properties of SCUBA cores in Perseus mol. cloud (Curtis+, 2010)

    NASA Astrophysics Data System (ADS)

    Curtis, E. I.; Richer, J. S.

    2013-05-01

    We extracted fully calibrated and reduced SCUBA 850um maps across the four regions in Perseus we observed with HARP from the data presented by Hatchell et al. (2005, Cat. J/A+A/440/151), where we refer the reader for details of the observations and processing. In short, the data were taken during 20 nights between 1999 and 2003. (2 data files).

  19. [Storage of cereal bars with mesquite cotyledon (Prosopis chilensis (Mol) Stuntz)].

    PubMed

    Escobar, B; Estévez, A M; Guiñez, M A

    2000-06-01

    The use of walnut or peanut in the elaboration of cereal bars represents a possible risk of undesirable changes during their storage due to their high content of unsaturated fatty acids in the oil; oxidizing of the fatty acids is one of the main causes of deterioration. Development of new snack products implies the use of packages that should protect the food against the damage caused by light and reduce the oxygen concentration of in their interior. The objective of this investigation was to evaluate the physical, chemical and sensory changes in the storage of cereal bars with peanut or walnut and mezquite cotyledon subjected to two thermal treatments, packed in cellophane or milky polypropilene. Four types of bars were elaborated with 6% of mezquite cotyledon, treated by microwaves or toasted, and with 18% of peanut or walnut. The bars were stored for 90 days at room temperature; and each 30 days it was measured moisture content, peroxides index, water activity, sensory quality and acceptability. The peroxides values (4.9-13.8 meq/kg of oil) indicates that the shelf life of the bars in all the studied treatments was 90 days. The packaging materials used allows to maintain in good conditions, for 3 months, the cereals bars of moisture (7.4-11.2%), water activity (0.50-0.65) and sensory acceptability.

  20. ExoMol molecular line lists - XIV. The rotation-vibration spectrum of hot SO2

    NASA Astrophysics Data System (ADS)

    Underwood, Daniel S.; Tennyson, Jonathan; Yurchenko, Sergei N.; Huang, Xinchuan; Schwenke, David W.; Lee, Timothy J.; Clausen, Sønnik; Fateev, Alexander

    2016-07-01

    Sulphur dioxide is well-known in the atmospheres of planets and satellites, where its presence is often associated with volcanism, and in circumstellar envelopes of young and evolved stars as well as the interstellar medium. This work presents a line list of 1.3 billion 32S16O2 vibration-rotation transitions computed using an empirically adjusted potential energy surface and an ab initio dipole moment surface. The list gives complete coverage up to 8000 cm-1 (wavelengths longer than 1.25 μm) for temperatures below 2000 K. Infrared absorption cross-sections are recorded at 300 and 500 C are used to validated the resulting ExoAmes line list. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.

  1. Plasma etch challenges with new EUV lithography material introduction for patterning for MOL and BEOL

    NASA Astrophysics Data System (ADS)

    Lee, Changwoo; Nagabhirava, Bhaskar; Goss, Michael; Wang, Peng; Friddle, Phil; Schmitz, Stafan; Wu, Jian; Yang, Richard; Mignot, Yann; Rassoul, Nouradine; Hamieh, Bassem; Beique, Genevieve; Labonte, Andre; Labelle, Catherine; Arnold, John; Mucci, John

    2015-03-01

    As feature critical dimension (CD) shrinks towards and beyond the 7nm node, patterning techniques for optical lithography with double and triple exposure will be replaced by EUV patterning. EUV enables process and overlay improvement, as well as a potential cost reduction due to fewer wafer passes and masks required for patterning. However, the EUV lithography technique introduces newer types of resists that are thinner and softer compared to conventional 193nm resists currently being used. The main challenge is to find the key etch process parameters to improve the EUV resist selectivity, reduce LER and LWR, minimize line end shrink, improve tip-to-tip degradation, and avoid line wiggling while still enabling previous schemes such as trench-first-metal-hard-mask (TFMHM), self-aligned via (SAV) and self-aligned contact (SAC). In this paper, we will discuss some of the approaches that we have investigated to define the best etch process adjustments to enable EUV patterning. RF pulsing is one of the key parameters utilized to overcome most of the previously described challenges, and has also been coupled with stack optimization. This study will focus on RF pulsing (high vs. low frequency results) and bias control (RF frequency dependence). In particular, pulsing effects on resist morphology, selectivity and profile management will be reported, as well as the role of aspect ratio and etch chemistry on organic mask wiggling and collapse. This work was performed by the Research Alliance Teams at various IBM Research and Development Facilities.

  2. Metastability of the martensitic transformation in a 12 mol% ceria-zirconia alloy; II, grinding studies

    SciTech Connect

    Swain, M.V.; Hannink, R.H.J. . Div. of Materials Science and Technology)

    1989-08-01

    Observations of the grinding-induced transformation in single-phase Ce-TZP materials, referred to in an earlier paper, are presented. Two techniques were used to grind the surface: by hand in a slurry of abrasive particles and with a high-speed diamond-impregnated wheel. Significant differences in X-ray diffraction profiles between the two grinding methods were observed. Limited monoclinic ZrO/sub 2/ was detected on the machine-ground surface, along with the reversal of the tetragonal ZrO/sub 2/ (200) peak intensities. On the hand-ground surface, considerable monoclinic phase was observed. Transmission electron microscope studies at various depths below the ground surface were undertaken to identify the differences between these surfaces and fractured surfaces. A simple explanation is proposed for the reversal of the tetragonal peak intensities.

  3. Batch and Continuous Ultrasound Assisted Extraction of Boldo Leaves (Peumus boldus Mol.).

    PubMed

    Petigny, Loïc; Périno-Issartier, Sandrine; Wajsman, Joël; Chemat, Farid

    2013-03-12

    Vegetal extracts are widely used as primary ingredients for various products from creams to perfumes in the pharmaceutical, nutraceutic and cosmetic industries. Having concentrated and active extract is essential, as the process must extract as much soluble material as possible in a minimum time, using the least possible volume of solvent. The boldo leaves extract is of great interest for the industry as it holds a great anti-oxidant activity due to high levels of flavonoids and alkaloids such as boldine. Ultrasound Assisted Extraction (UAE) has been used to improve the efficiency of the plant extraction, reducing extraction time, increasing the concentration of the extract with the same amount of solvent and plant material. After a preliminary study, a response surface method has been used to optimize the extraction of soluble material from the plant. The results provided by the statistical analysis revealed that the optimized conditions were: sonication power 23 W/cm2 for 40 min and a temperature of 36 °C. The optimized parameters of the UAE provide a better extraction compared to a conventional maceration in terms of process time (30 min instead of 120 min), higher yield, more energy saving, cleanliness, safety and product quality.

  4. Free-radical scavengers and antioxidants from Peumus boldus Mol. ("Boldo").

    PubMed

    Schmeda-Hirschmann, G; Rodriguez, J A; Theoduloz, C; Astudillo, S L; Feresin, G E; Tapia, A

    2003-04-01

    The dry leaves of Peumus boldus (Monimiaceae) are used in infusion or decoction as a digestive and to improve hepatic complains. Preliminary assays showed free-radical scavenging activity in hot water extracts of boldo leaves, measured by the decoloration of a methanolic solution of the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH). Assay-guided isolation led to the active compounds. Catechin proved to be the main free-radical scavenger of the extracts. Lipid peroxidation in erythrocytes was inhibited by boldo extracts and fractions at 500 microg/ml with higher effect for the ethyl acetate soluble and alkaloid fractions. The IC50 for catechin and boldine in the lipid peroxidation test were 75.6 and 12.5 microg/ml, respectively. On the basis of dry starting material the catechin content in the crude drug was 2.25% while the total alkaloid calculated as boldine was 0.06%. The activity of boldine was six times higher than catechin in the lipid peroxidation assay. However, the mean catechin:total alkaloid content ratio was 37:1. The relative concentration of alkaloids and phenolics in boldo leaves and their activity suggest that free-radical scavenging effect is mainly due to catechin and flavonoids and that antioxidant effect is mainly related with the catechin content The high catechin content of boldo leaves and its bioactivity suggest that quality control of Boldo folium has to combine the analysis of catechin as well as their characteristic aporphine alkaloids.

  5. ExoMol molecular line lists - XVII. The rotation-vibration spectrum of hot SO3

    NASA Astrophysics Data System (ADS)

    Underwood, Daniel S.; Yurchenko, Sergei N.; Tennyson, Jonathan; Al-Refaie, Ahmed F.; Clausen, Sønnik; Fateev, Alexander

    2016-11-01

    Sulphur trioxide (SO3) is a trace species in the atmospheres of the Earth and Venus, as well as being an industrial product and an environmental pollutant. A variational line list for 32S16O3, named UYT2, is presented containing 21 billion vibration-rotation transitions. UYT2 can be used to model infrared spectra of SO3 at wavelengths longwards of 2 μm (ν < 5000 cm-1) for temperatures up to 800 K. Infrared absorption cross-sections recorded at 300 and 500 C are used to validate the UYT2 line list. The intensities in UYT2 are scaled to match the measured cross-sections. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.

  6. Antioxidant Compound Extraction from Maqui (Aristotelia chilensis [Mol] Stuntz) Berries: Optimization by Response Surface Methodology

    PubMed Central

    Quispe-Fuentes, Issis; Vega-Gálvez, Antonio; Campos-Requena, Víctor H.

    2017-01-01

    The optimum conditions for the antioxidant extraction from maqui berry were determined using a response surface methodology. A three level D-optimal design was used to investigate the effects of three independent variables namely, solvent type (methanol, acetone and ethanol), solvent concentration and extraction time over total antioxidant capacity by using the oxygen radical absorbance capacity (ORAC) method. The D-optimal design considered 42 experiments including 10 central point replicates. A second-order polynomial model showed that more than 89% of the variation is explained with a satisfactory prediction (78%). ORAC values are higher when acetone was used as a solvent at lower concentrations, and the extraction time range studied showed no significant influence on ORAC values. The optimal conditions for antioxidant extraction obtained were 29% of acetone for 159 min under agitation. From the results obtained it can be concluded that the given predictive model describes an antioxidant extraction process from maqui berry.

  7. Batch and Continuous Ultrasound Assisted Extraction of Boldo Leaves (Peumus boldus Mol.)

    PubMed Central

    Petigny, Loïc; Périno-Issartier, Sandrine; Wajsman, Joël; Chemat, Farid

    2013-01-01

    Vegetal extracts are widely used as primary ingredients for various products from creams to perfumes in the pharmaceutical, nutraceutic and cosmetic industries. Having concentrated and active extract is essential, as the process must extract as much soluble material as possible in a minimum time, using the least possible volume of solvent. The boldo leaves extract is of great interest for the industry as it holds a great anti-oxidant activity due to high levels of flavonoids and alkaloids such as boldine. Ultrasound Assisted Extraction (UAE) has been used to improve the efficiency of the plant extraction, reducing extraction time, increasing the concentration of the extract with the same amount of solvent and plant material. After a preliminary study, a response surface method has been used to optimize the extraction of soluble material from the plant. The results provided by the statistical analysis revealed that the optimized conditions were: sonication power 23 W/cm2 for 40 min and a temperature of 36 °C. The optimized parameters of the UAE provide a better extraction compared to a conventional maceration in terms of process time (30 min instead of 120 min), higher yield, more energy saving, cleanliness, safety and product quality. PMID:23481637

  8. Mol-Gastronomie Von Schäumen und Träumen

    NASA Astrophysics Data System (ADS)

    Vilgis, Thomas A.

    2005-01-01

    Traumhafte Souffles, köstliches Schokoladenmus, süße Meringuen, lockere Biskuits, wem läuft bei diesen Kulinarien nicht das Wasser im Munde zusammen. In Abwandlung des Sprichworts erweisen sich solche Schäume tatsächlich als Träume, jedenfalls zu Tisch.

  9. ExoMol line lists - XVIII. The high-temperature spectrum of VO

    NASA Astrophysics Data System (ADS)

    McKemmish, Laura K.; Yurchenko, Sergei N.; Tennyson, Jonathan

    2016-11-01

    An accurate line list, VOMYT, of spectroscopic transitions is presented for hot VO. The 13 lowest electronic states are considered. Curves and couplings are based on initial ab initio electronic structure calculations and then tuned using available experimental data. Dipole moment curves, used to obtain transition intensities, are computed using high levels of theory (e.g. MRCI/aug-cc-pVQZ using state-specific or minimal-state complete active space for dipole moments). This line list contains over 277 million transitions between almost 640 000 energy levels. It covers the wavelengths longer than 0.29 μm and includes all transitions from energy levels within the lowest nine electronic states which have energies less than 20 000 cm-1 to upper states within the lowest 13 electronic states which have energies below 50 000 cm-1. The line lists give significantly increased absorption at infrared wavelengths compared to currently available VO line lists. The full line lists is made available in electronic form via the CDS database and at www.exomol.com.

  10. Seismic Monitoring at the Underground Nuclear Research Laboratory in Mol, Belgium - 12461

    SciTech Connect

    Areias, Lou

    2012-07-01

    Micro-seismic piezoelectric transmitters installed in the Boom Clay at HADES produce predominantly high frequency signals, above 5 kHz, which favour the generation of P waves. However, above 5 kHz shear (S) waves are not detected by the installation. Recent studies at HADES indicate that it is possible to detect S waves with the current setup when applying a low (5 kHz) cut-off filter. The results also show that S waves have frequencies mainly below 1 kHz, while P waves are detectable at all of the eight transmitted frequencies but show optimum resolution in the range of 7 to 23 kHz. Although the system offers great potential for monitoring the evolution of a geological disposal site, further improvements in signal generation and treatment are necessary. One of these includes the design and testing of a new S-wave source at HADES planned in the framework of the EC MoDeRn project (http://www.modern-fp7.eu/). The seismic installation at HADES continues to provide useful information on the changing properties of the Boom Clay in the near and far field around the PRACLAY gallery since its start of operation in 2006. In the future, the system will also monitor the PRACLAY heater experiment that will start in 2012 and go on for 10 years. So far, the results of long term seismic monitoring show that S waves contain frequencies mainly below 1 kHz. The P waves are detectable at all of the eight transmitted frequencies but show optimum resolution in the range of 7 to 23 kHz. To improve the signal-to-noise ratio and detection of S waves at HADES it is, therefore, necessary to apply a strong low-pass filter that matches the S-wave frequency content. Due to the different frequency ranges observed for the P and S waves, it is recommended to treat them separately. The evolution of both P and S wave velocities in the EDZ around the PRACLAY gallery show continued recovery since its construction in 2007. Modelling results of the variation in crack density obtained from the inversion of the modelled P-wave transmission velocities further confirm the recovery of the EDZ and the self-healing properties of the Boom Clay. (authors)

  11. VizieR Online Data Catalog: ExoMol line lists for SO2 (Underwood+, 2016)

    NASA Astrophysics Data System (ADS)

    Underwood, D. S.; Tennyson, J.; Yurchenko, S. N.; Huang, X.; Schwenke, D. W.; Lee, T. J.; Clausen, S.; Fateev, A.

    2016-03-01

    The data are in two parts. The first, 32S-16O2.states contains a list of rovibrational states. Each state is labelled with 3 vibrational (v1, v2, v3) and 3 rotational (J, Ka, Kc) quantum numbers and total parity. The total degeneracy is also given to facilitate the intensity calculations. Because of their size, the transitions are listed in 80 separate files, each containing all the transitions in a 100cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range and the upper frequency limit; thus the 32S-16O2ExoAmes00500-00600.trans file contains all the transitions in the frequency range 500-600cm-1 but not including 600cm-1. The transition files 32S-16O2ExoAmesxxxxx-yyyyy.trans contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. (2 data files).

  12. ExoMol line lists - XV. A new hot line list for hydrogen peroxide

    NASA Astrophysics Data System (ADS)

    Al-Refaie, Ahmed F.; Polyansky, Oleg L.; Ovsyannikov, Roman I.; Tennyson, Jonathan; Yurchenko, Sergei N.

    2016-09-01

    A computed line list for hydrogen peroxide, H216O2, applicable to temperatures up to T = 1250 K is presented. A semi-empirical high-accuracy potential energy surface is constructed and used with an ab initio dipole moment surface as input TROVE to compute 7.5 million rotational-vibrational states and around 20 billion transitions with associated Einstein-A coefficients for rotational excitations up to J = 85. The resulting APTY line list is complete for wavenumbers below 6000 cm-1 (λ < 1.67 μm) and temperatures up to 1250 K. Room-temperature spectra are compared with laboratory measurements and data currently available in the HITRAN data base and literature. Our rms with line positions from the literature is 0.152 cm-1 and our absolute intensities agree better than 10 per cent. The full line list is available from the CDS data base as well as at www.exomol.com.

  13. VizieR Online Data Catalog: ExoMol line lists for CH4 (Yurchenko+, 2014)

    NASA Astrophysics Data System (ADS)

    Yurchenko, S. N.; Tennyson, J.

    2014-02-01

    The data are in two parts. The first, ch4_0-39.dat contains a list of 7,819,352 rovibrational states. Each state is labelled with: nine normal mode vibrational quantum numbers and the vibrational symmety; three rotational quantum numbers including the total angular momentum J and rotational symmetry; the total symmetry quantum number Gamma and the running number in the same (J,Gamma,Polyad) combination, where Polyad is a polyad number (see paper). In addition there are nine local mode vibrational numbers and the largest coefficient used to assign the state in question. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The total degeneracy is also given to facilitate the intensity calculations. Because of their size, the transitions are listed in 120 separate files, each containing all the transitions in a 100cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-00500.dat file contains all the transitions in the frequency range 500-600cm-1. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, s_10to10.f90 which may be used to generate synthetic spectra (see s_10to10.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else cross-sections convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Sample input files s*.inp for use with s10to10.f90 are supplied. (9 data files).

  14. Using the PyMOL Application to Reinforce Visual Understanding of Protein Structure

    ERIC Educational Resources Information Center

    Rigsby, Rachel E.; Parker, Alison B.

    2016-01-01

    Visualization of chemical concepts can be challenging for many students. This is arguably a critical skill for beginning students of biochemistry to develop, since new information is often presented visually in the form of textbook figures. It is recommended that visual literacy be explicitly taught in the classroom rather than assuming that…

  15. PyMOL mControl: Manipulating Molecular Visualization with Mobile Devices

    ERIC Educational Resources Information Center

    Lam, Wendy W. T.; Siu, Shirley W. I.

    2017-01-01

    Viewing and manipulating three-dimensional (3D) structures in molecular graphics software are essential tasks for researchers and students to understand the functions of molecules. Currently, the way to manipulate a 3D molecular object is mainly based on mouse-and-keyboard control that is usually difficult and tedious to learn. While gesture-based…

  16. Crystalline Forms in a Copolymer of Vinylidene Fluoride and Trifluoroethylene (52/48 Mol %).

    DTIC Science & Technology

    1981-11-01

    ethylene, provided by Daikin Kogyo Co., Ltd, Japan. 23 They had been prepared by bulk polymerization at 221C using a peroxide initiator, and were in...transition region. ACKNOWLEDGEMENTS We would like to thank Drs. J. Sako of Daikin Kogyo Co., Ltd., and R. Ferren of Pennwalt Corp. for pro- vision of

  17. In situ chemical osmosis experiment in the Boom Clay at the Mol underground research laboratory

    NASA Astrophysics Data System (ADS)

    Garavito, A. M.; De Cannière, P.; Kooi, H.

    Studies on the compatibility of Boom Clay with large amounts of nitrate- bearing bituminized radioactive waste have recently raised a particular interest for osmosis-induced effects in this reference formation in Belgium. Indeed, water flow and solute transport may be associated with several types of driving forces, or gradients (chemical, electrical, thermal), in addition to the hydraulic forces, resulting in the so-called coupled flows. Fluid flow caused by driving forces different than hydraulic gradients is referred to as osmosis. Chemical osmosis, the water flow induced by a chemical gradient across a semi-permeable membrane, can generate pressure increase. The question thus arises if there is a risk to create high pore pressures that could damage the near-field of medium-level waste (MLW) galleries, if osmotically driven water flows towards the galleries are produced by the release of large amounts of NaNO 3 (750 t) in the formation. To what extent a low-permeability clay formation such as the Boom Clay acts as an osmotic membrane is thus a key issue to assess the relevance of osmosis phenomena for the disposal of medium-level waste. An in situ osmosis experiment has been conducted at the H ADES underground research laboratory to determine the osmotic efficiency of Boom Clay at the field scale. A recently developed chemical osmosis flow continuum model has been used to design the osmosis experiment, and to interpret the water pressure measurements. Experimental data could be reproduced quite accurately by the model, and the inferred parameter values are consistent with independent determinations for Boom Clay. A rapid water pressure increase (but limited to about a 2 m water column) was observed after 12 h in the filter containing the more saline water. Then, the osmotically induced water pressure slowly decays on several months. So, the experimental results obtained in situ confirm the occurrence of non-hydraulic flow phenomena (chemical osmosis) in a low-permeability plastic formation such as the Boom Clay. The osmotic efficiency of Boom Clay is high under undisturbed chemical conditions ( σ = 0.41 at 0.014 M NaHCO 3), but rapidly decreases when the dissolved salts concentration increases ( σ = 0.07 at 0.14 M NaHCO 3). A semi-permeable membrane behaviour of the Boom Clay (high efficiencies) may be expected for the disposal of nitrate-bearing radioactive waste. However, the presently observed osmotically induced pressure is too low to have a significant mechanical impact on the host rock. Finally, the short duration of the osmosis test performed suggests that the shut-in test method used is effective for osmosis testing.

  18. Zepto-molar electrochemical detection of Brucella genome based on gold nanoribbons covered by gold nanoblooms

    NASA Astrophysics Data System (ADS)

    Rahi, Amid; Sattarahmady, Naghmeh; Heli, Hossein

    2015-12-01

    Gold nanoribbons covered by gold nanoblooms were sonoelectrodeposited on a polycrystalline gold surface at -1800 mV (vs. AgCl) with the assistance of ultrasound and co-occurrence of the hydrogen evolution reaction. The nanostructure, as a transducer, was utilized to immobilize a Brucella-specific probe and fabrication of a genosensor, and the process of immobilization and hybridization was detected by electrochemical methods, using methylene blue as a redox marker. The proposed method for detection of the complementary sequence, sequences with base-mismatched (one-, two- and three-base mismatches), and the sequence of non-complementary sequence was assayed. The fabricated genosensor was evaluated for the assay of the bacteria in the cultured and human samples without polymerase chain reactions (PCR). The genosensor could detect the complementary sequence with a calibration sensitivity of 0.40 μA dm3 mol-1, a linear concentration range of 10 zmol dm-3 to 10 pmol dm-3, and a detection limit of 1.71 zmol dm-3.

  19. Nanostructured crystals of fluorite phases Sr{sub 1−x}R{sub x}F{sub 2+x} (R Are Rare Earth Elements) and their ordering: 10. Ordering under spontaneous crystallization and annealing of Sr{sub 1−x}R{sub x}F{sub 2+x} Alloys (R = Tb-Lu, Y) with 23.8–36.1 mol % RF{sub 3}

    SciTech Connect

    Sulyanova, E. A. Karimov, D. N.; Sulyanov, S. N.; Zhmurova, Z. I.; Golubev, A. M.; Sobolev, B. P.

    2015-01-15

    The products of spontaneous crystallization (at a cooling rate of ∼200 K/min) of Sr{sub 1−x}R{sub x}F{sub 2+x} melts in the homogeneity range of the fluorite phase have been investigated. Thirty-two irrational compositions with 23.8–36.1 mol % RF{sub 3} and eight rational Sr{sub 2}RF{sub 7} compositions are obtained. With respect to the RF{sub 3} content, these compositions form five groups: (1) Sr{sub 0.762}R{sub 0.238}F{sub 2.238} (23.8% RF{sub 3}), (2) Sr{sub 0.744}R{sub 0.256}F{sub 2.256} (25.6%), (3) Sr{sub 0.718}R{sub 0.282}F{sub 2.282} (28.2%), (4) Sr{sub 2}RF{sub 7} (33.3%), and (5) Sr{sub 0.639}R{sub 0.361}F{sub 2.361} (36.1%). R = Tb-Lu, Y for all groups. Quenching melts of group 5 with R = Tb, Dy, and Ho leads to the formation of ordered phases with the trigonal distortion of the rhβ-Na{sub 7}Zr{sub 6}F{sub 31} type, while for melts of group 5 with R = Lu, quenching yields a phase of the trigonal rhα′-Sr{sub 4}Lu{sub 3}F{sub 17} type. In group 5 with R = Y, Er, Tm, or Yb and in groups 1–4 with all REEs, fluorite phases are formed. Annealing at 900 ± 20°C for 96 h with subsequent cooling at a rate of ∼200 K/min expands the variety of ordered phases: a phase with a new r type of orthorhombic distortion is formed in group 1 with R = Lu, in group 2 with R = Tm or Lu, and in group 3 with R = Ho-Lu, Y; a t-Sr{sub 2}RF{sub 7} phase with tetragonal distortion is formed in group 4 with R = Tb-Er, Y; and a phase of trigonal rhα′ type is formed in group 5 with R = Y, Yb, or Lu. A fluorite phase arises in group 1 with R = Tb-Lu, Y as a result of quenching and annealing. The tendency to ordering becomes more pronounced with an increase in the RF{sub 3} content and REE atomic number. The annealing conditions do not provide equilibrium or the completely ordered state of all alloys.

  20. Medical Laboratory Technician--Hematology, Serology, Blood Banking & Immunohematology, 10-4. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This course, the third of three courses in the medical laboratory technician field adapted from military curriculum materials for use in vocational and technical education, was designed as a refresher course for student self-study and evaluation. It is suitable for use by advanced students or beginning students participating in a supervised…

  1. Low-temperature NMR characterization of reaction of sodium pyruvate with hydrogen peroxide.

    PubMed

    Asmus, Christopher; Mozziconacci, Olivier; Schöneich, Christian

    2015-02-12

    It was proposed that the reaction of sodium pyruvate and H2O2 generates the intermediate 2-hydroperoxy-2-hydroxypropanoate, which converts into acetate, CO2, and H2O ( Aleksankin et al. Kernenergie 1962 , 5 , 362 - 365 ). These conclusions were based on the products generated in (18)O-enriched water and H2O2 reacting with pyruvic acid at room temperature; however, the lifetime of 2-hydroperoxy-2-hydroxypropanoate at room temperature is too short for direct spectroscopic observation. Therefore, we applied the combination of low-temperature and (13)C NMR techniques to verify, for the first time, the formation of 2-deuteroperoxy-2-deuteroxypropanoate in mixtures of D2O and methanol-d4 and to monitor directly each species involved in the reaction between D2O2 and (13)C-enriched pyruvate. Our NMR results confirm the formation of 2-deuteroperoxy-2-deuteroxypropanoate, where the respective chemical shifts are supported by density functional theory (DFT) calculations. At near-neutral apparent pD (pD*) and -35 °C, the formation of 2-deuteroperoxy-2-deuteroxypropanoate occurred with k = 2.43 × 10(-3) dm(3mol(-1)·s(-1). The subsequent decomposition of 2-deuteroperoxy-2-deuteroxypropanoate into acetate, CO2, and D2O occurred with k = 2.58 × 10(-4) s(-1) at -35 °C. In order to provide a full kinetic analysis, we also monitored the equilibrium of pyruvate and methanol with the hemiacetal (2-deuteroxy-2-methoxypropanoate). The kinetics for the reaction of sodium pyruvate and D2O2 were fitted by taking into account all these equilibria and species.

  2. The effect of hydrogen peroxide on uranium oxide films on 316L stainless steel

    NASA Astrophysics Data System (ADS)

    Wilbraham, Richard J.; Boxall, Colin; Goddard, David T.; Taylor, Robin J.; Woodbury, Simon E.

    2015-09-01

    For the first time the effect of hydrogen peroxide on the dissolution of electrodeposited uranium oxide films on 316L stainless steel planchets (acting as simulant uranium-contaminated metal surfaces) has been studied. Analysis of the H2O2-mediated film dissolution processes via open circuit potentiometry, alpha counting and SEM/EDX imaging has shown that in near-neutral solutions of pH 6.1 and at [H2O2] ⩽ 100 μmol dm-3 the electrodeposited uranium oxide layer is freely dissolving, the associated rate of film dissolution being significantly increased over leaching of similar films in pH 6.1 peroxide-free water. At H2O2 concentrations between 1 mmol dm-3 and 0.1 mol dm-3, formation of an insoluble studtite product layer occurs at the surface of the uranium oxide film. In analogy to corrosion processes on common metal substrates such as steel, the studtite layer effectively passivates the underlying uranium oxide layer against subsequent dissolution. Finally, at [H2O2] > 0.1 mol dm-3 the uranium oxide film, again in analogy to common corrosion processes, behaves as if in a transpassive state and begins to dissolve. This transition from passive to transpassive behaviour in the effect of peroxide concentration on UO2 films has not hitherto been observed or explored, either in terms of corrosion processes or otherwise. Through consideration of thermodynamic solubility product and complex formation constant data, we attribute the transition to the formation of soluble uranyl-peroxide complexes under mildly alkaline, high [H2O2] conditions - a conclusion that has implications for the design of both acid minimal, metal ion oxidant-free decontamination strategies with low secondary waste arisings, and single step processes for spent nuclear fuel dissolution such as the Carbonate-based Oxidative Leaching (COL) process.

  3. Quantitative determination of betamethasone sodium phosphate and betamethasone dipropionate in human plasma by UPLC-MS/MS and a bioequivalence study.

    PubMed

    Chen, Man-Yun; Tang, Yong-Jun; Wang, Yi-Cheng; Wang, Chong-Zhi; Yuan, Chun-Su; Chen, Yao; Tan, Zhi-Rong; Huang, Wei-Hua; Zhou, Hong-Hao

    2016-05-07

    The compound medicine of betamethasone sodium phosphate (BSP) and betamethasone dipropionate (BDP) is widely used for diverse glucocorticoid-sensitive acute and chronic diseases such as asthma, rheumatoid arthritis and systemic lupus erythematosus. It will be useful and beneficial to validate sensitive method for the determination of BSP, BDP and their metabolites for their pharmacokinetic study. Hereby, an ultra-high pressure liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been validated for the determination of BSP, BDP and their metabolites betamethasone (BOH), betamethasone 17-monodipropionate (B17P) and betamethasone 21-monodipropionate (B21P) in human plasma. Liquid-liquid extraction with ether and n-hexane (v/v, 4:1) was used for sample preparation of BDP, BOH, B17P and B21P with beclomethasone dipropionate as internal standard (IS), while solid phase extraction was adopted for sample preparation of BSP using prednisolone as IS. The chromatographic separation was performed on a Hypurity C18 column (150 mm×2.1 mm, 5 μm) for BOH, BDP, B21P and B17P, and a Luna C18 (2) column (150 mm×2.0 mm, 5 μm) for BSP. Electrospray ionization interfaced with positive multiple reaction monitoring (MRM) scan mode was used for mass spectrometric detection. The standard calibration curves were linear within the range of 2.525 × 10(-9)-403.9 × 10(-9) mol·dm(-3) for BSP, 0.125 × 10(-9)-55.81 × 10(-9) mol·dm(-3) for BDP, 0.278 × 10(-9)-74.95 × 10(-9) mol·dm(-3) for BOH, 0.098 × 10(-9)-4.688 × 10(-9) mol·dm(-3) for B17P and 0.226 × 10(-9)-5.411 × 10(-9) mol·dm(-3) for B21P, respectively. The validated method was successfully applied to a bioequivalence study in 23 healthy subjects after they were injected with this compound medicine BSP and BDP.

  4. Equilibrium constant of the gamma-sultone and extraction constant of sodium and potassium ions from water into benzene in presence of 18-crown-6 and bromocresol green.

    PubMed

    Kolthoff, Izaak M; Chantooni, Miran K; Jyo, Akinori

    2002-07-03

    An extraction procedure for the spectrophotometric determination of sodium or potassium involving a 1:1:1 metal ion: crown ether: sulfonephthalein dye monoanion ion associate has been described in the literature. In a recent paper from this laboratory the total dye content of the organic phase resulting from partitioning bromocresol green (HBCG) alone between water and benzene was determined from back extraction into an aqueous phosphate buffer. In benzene, bromocresol green is present to a large extent as a colorless lactone form, or gamma-sultone. The sultone equilibrium constant, K(dist) (sultone)=[sultone](o)/[BCG(-)](w)gamma(BCG(-))(w)a(H(+)) was found to be 373+/-42 mol(-1) dm(3). In the present study, sodium was extracted from water into benzene with 18-crown-6 and BCG(-), yielding K(dist) (sultone)=232 mol(-1) dm(3) and the conventional extraction constant, K(ex), of (5.49+/-0.49)x10(3) mol(-2) dm(6). Corresponding values from potassium extraction data are 256 mol(-1) dm(3) and (4.80+/-0.51)x10(6) mol(-2) dm(6), respectively. In the absence of ethanol, the calibration plot of sodium closely followed Beer's law, but that of potassium curved downward, approaching linearity in 15% ethanol. High 18-crown-6, low bromocresol green concentrations are analytically favorable for the extraction of potassium from the 15% aqueous ethanol mixture. All plots from the back-extractions (a measure of the total dye content in the benzene phase) were linear. Ethanol markedly reduced the reagent blank, when C(MCl)=0, as a result of the sultone being partitioned less favorably into benzene.

  5. Amperometric catechol biosensor based on polyaniline-polyphenol oxidase.

    PubMed

    Tan, Yongyan; Guo, Xiaoxia; Zhang, Jinghui; Kan, Jinqing

    2010-03-15

    A novel catechol biosensor was described based on the immobilization of polyphenol oxidase (PPO) into polyaniline (PANI), which was easily constructed by direct electropolymerization of aniline in a solution containing ionic liquid, 1-ethyl-3-methylimidazolium ethyl sulfate (EMIES). The developed biosensor for the detection of catechol has a linear range of 1.25-150 micromol dm(-3). The maximum response current (I(max)) and the Michaelis-Menten constant (k'(m)) are 0.62 microA and 146 micromol dm(-3), respectively. The activation energy (E(a)) of the PPO catalytic reaction is 31.1 kJ mol(-1) in the B-R buffer. The biosensor shows good reproducibility (a relative standard deviation of 3.1% was obtained) and remarkable long-term stability (it retains 75% of the original activity after four months). The effects of potential and pH on the response current of the biosensor are also described.

  6. Non-enzymatic glucose biosensor based on hyperbranched pine-like gold nanostructure.

    PubMed

    Heli, H; Amirizadeh, O

    2016-06-01

    Hyperbranched pine-like gold nanostructure was electrodeposited on the polycrystalline gold surface at 0 mV (vs. AgCl) with the assistance of histidine as a soft template. The nanostructure was then applied as a highly sensitive nonenzymatic sensor for glucose. The catalytic activity and sensitivity of the gold nanostructure toward the electrooxidation of glucose was excellent without surface fouling and deterioration effects. The current related to the oxidation of glucose rapidly and linearly depended on its concentration with a sensitivity of 776.8 μA cm(-2)mmol(-1)dm(3), a detection limit of 3.39 μmol dm(-3) with a relative standard deviation of 2.32%.

  7. The study of secondary effects in vibrational and hydrogen bonding properties of 2- and 3-ethynylpyridine and ethynylbenzene by IR spectroscopy.

    PubMed

    Vojta, Danijela; Matanović, Ivana; Kovačević, Goran; Baranović, Goran

    2014-11-11

    Weak hydrogen bonds formed by 2- and 3-ethynylpyridine and ethynylbenzene with trimethylphosphate and phenol were characterized by IR spectroscopy and DFT calculations (B3LYP/6-311++G(d, p)). The structure and stability of ethynylpyridines and ethynylbenzene in the gas phase and in the complexes with trimethylphosphate and phenol are discussed in terms of geometry and electronic charge redistribution. Anharmonic effects are taken into account when calculating vibrational wavenumbers of these systems what lead to partial improvement of agreement with experiment. The changes in the electronic charge distribution are behind the frequency shifts of the CC stretching in opposite direction depending on the role the ethyne molecule has in a hydrogen bonded complex (Δν̃=+9 cm(-1) in trimethylphosphate complexes, Δν̃=-3 cm(-1) in phenol complexes). The association constants were determined by keeping the concentrations of proton donors approximately constant and low enough to avoid self-association and the proton acceptors were present in excess. The values obtained for the association constants and enthalpy changes in C2Cl4 (for trimethylphosphate complexes K≈0.5-1.0 mol(-1)dm(3) and -ΔrH≈6-8 kJ mol(-1), for phenol complexes K≈20-40 mol(-1) dm3-ΔrH≈17-22 kJ mol(-1)) are in good agreement with literature data.

  8. Sorption potential of rice husk for the removal of 2,4-dichlorophenol from aqueous solutions: kinetic and thermodynamic investigations.

    PubMed

    Akhtar, Mubeena; Bhanger, M I; Iqbal, Shahid; Hasany, S Moosa

    2006-01-16

    The sorption potential of chemically and thermally treated rice husk (RHT) for the removal of 2,4-dichlorophenol (DCP) from aqueous solutions has been investigated. Sorption of DCP by rice husk was observed over a wide pH range of 1-10. The effect of contact time between liquid and solid phases, sorbent dose, pH, concentration of sorbate and temperature on the sorption of DCP onto rice husk has been studied. The pore area and average pore diameter of RHT by BET method are calculated to be 17+/-0.6 m2g-1 and 51.3+/-1.5 nm, respectively. Maximum sorption (98+/-1.2%) was achieved for RHT from 6.1x10(-5) moldm(-3) of sorbate solution using 0.1g of rice husk for 10 min agitation time at pH 6 and 303K, which is comparable to activated carbon commercial (ACC) 96.6+/-1.2%, but significantly higher than chemically treated rice husk (RHCT) 65+/-1.6% and rice husk untreated (RHUT) 41+/-2.3%. The sorption data obtained at optimized conditions was subjected to Freundlich, Langmuir and Dubinin-Radushkevich (D-R) isotherms. Sorption intensity 1/n (0.31+/-0.01) and sorption capacity multilayer C(m) (12.0+/-1.6 mmolg(-1)) have been evaluated using Freundlich sorption isotherm, whereas the values of sorption capacity monolayer Q (0.96+/-0.03 mmolg(-1)) and binding energy, b, (4.5+/-1.0)x10(4)dm(3)mol(-1) have been estimated by Langmuir isotherm. The Langmuir constant, b, was also used to calculate the dimensionless factor, R(L), in the concentration range (0.6-6.1)x10(-4) moldm(-3), suggesting greater sorption at low concentration. D-R sorption isotherm was employed to calculate sorption capacity X(m) (2.5+/-0.07 mmolg(-1)) and sorption energy E (14.7+/-0.13 kJmol(-1)). Lagergren and Morris-Weber equations were employed to study kinetics of sorption process using 0.2g of RHT, 25 cm(3) of 0.61x10(-4)moldm(-3) sorbate concentration at pH 6, giving values of first-order rate constant, k, and rate constant of intraparticle transport, R(id), (0.48+/-0.04 min(-1) and 6.8+/-0.8 nmolg(-1

  9. Synthesis, DNA binding and complex formation reactions of 3-amino-5,6-dimethyl-1,2,4-triazine with Pd(II) and some selected biorelevant ligands

    NASA Astrophysics Data System (ADS)

    Shoukry, Azza A.; Alghanmi, Reem M.

    2015-03-01

    With the purpose of studying the binding behavior of Pd(II) complexes with DNA as the main biological target, and their ability to penetrate reasonably into tumour cells and destroy their replication ability, Pd(ADT)Cl2 complex was synthesized and characterized, where ADT is 3-amino-5,6-dimethyl-1,2,4-triazine. Stoichiometry and stability constants of the complexes formed between various biologically relevant ligands (amino acids, amides, DNA constituents, and dicarboxylic acids) and [Pd(ADT)(H2O)2]2+ were investigated at 25 °C and at constant 0.1 mol dm-3 ionic strength. The concentration distribution diagrams of the various species formed are evaluated. Further investigation of the binding properties of the diaqua complex [Pd(ADT)(H2O)2]2+ with calf thymus DNA (CT-DNA) was investigated by UV-vis spectroscopy. The intrinsic binding constants (Kb) calculated from UV-vis absorption studies was calculated to be 2.00 × 103 mol dm-3. The calculated (Kb) value was found to be of lower magnitude than that of the classical intercalator EB (Ethidium bromide) (Kb = 1.23(±0.07) × 105 mol dm-3) suggesting an electrostatic and/or groove binding mode for the interaction with CT-DNA. Thermal denaturation has been systematically studied by spectrophotometric method and the calculated ΔTm was nearly 5 °C, supporting the electrostatic and/or groove binding mode for the interaction between the complex and CT-DNA

  10. 226Ra bioavailability to plants at the Urgeiriça uranium mill tailings site.

    PubMed

    Madruga, M J; Brogueira, A; Alberto, G; Cardoso, F

    2001-01-01

    Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeiriça mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment, some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides these plants, some shrubs (Cytisus spp.) are growing in some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings by quantifying the total and available fraction of radium in the tailings and to estimate its transfer to plants growing on the tailing piles. Plant and tailing samples were randomly collected and the activity concentration of 226Ra in plants (aerial part and roots) and tailings was measured by gamma-spectrometry. The exchangeable fraction of radium in tailings was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH = 7) or 1 mol dm-3 calcium chloride solutions. The results obtained for 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentrations in the tailings and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0 +/- 8.3 and 12.9 +/- 8.9, for the fraction of radium extracted from the tailings, using 1 mol dm-3 ammonium acetate or calcium chloride solutions, respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, at a 95% confidence level, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams.

  11. Drivers of summer oxygen depletion in the central North Sea

    NASA Astrophysics Data System (ADS)

    Queste, B. Y.; Fernand, L.; Jickells, T. D.; Heywood, K. J.; Hind, A. J.

    2015-06-01

    In stratified shelf seas, oxygen depletion beneath the thermocline is a result of a greater rate of biological oxygen demand than the rate of supply of oxygenated water. Suitably equipped gliders are uniquely placed to observe both the supply through the thermocline and the consumption of oxygen in the bottom layers. A Seaglider was deployed in the shallow (≈ 100 m) stratified North Sea in a region of known low oxygen during August 2011 to investigate the processes regulating supply and consumption of dissolved oxygen below the pycnocline. The first deployment of such a device in this area, it provided extremely high resolution observations, 316 profiles (every 16 min, vertical resolution of 1 m) of CTD, dissolved oxygen concentrations, backscatter and fluorescence during a three day deployment. The high temporal resolution observations revealed occasional small scale events that supply oxygenated water into the bottom layer at a rate of 2±1 μmol dm-3 day-1. Benthic and pelagic oxygen sinks, quantified through glider observations and past studies, indicate more gradual background consumption rates of 2.5±1 μmol dm-3 day-1. This budget revealed that the balance of oxygen supply and demand is in agreement with previous studies of the North Sea. However, the glider data show a net oxygen consumption rate of 2.8±0.3 μmol dm-3 day-1 indicating a localised or short-lived increase in oxygen consumption rates. This high rate of oxygen consumption is indicative of an unidentified oxygen sink. We propose that this elevated oxygen consumption is linked to localised depocentres and rapid remineralisation of resuspensded organic matter. The glider proved to be an excellent tool for monitoring shelf sea processes despite challenges to glider flight posed by high tidal velocities, shallow bathymetry, and very strong density gradients. The direct observation of these processes allows more up to date rates to be used in the development of ecosystem models.

  12. Evaluation of interfacial equilibrium constants from surface potential data: silver chloride aqueous interface.

    PubMed

    Preocanin, Tajana; Supljika, Filip; Kallay, Nikola

    2009-09-15

    A single crystal silver chloride electrode (SCr-AgCl) was used to measure the inner surface potential (Psi(0)) at the silver chloride aqueous electrolyte interface as a function of activity of Cl(-) ions as determined by the Ag/AgCl electrode. Absolute values of the surface potential were calculated from electrode potentials of SCr-AgCl using the value of point of zero charge (pCl(pzc)=5.2) as the value of point of zero potential. Measurements were performed in potassium nitrate aqueous solutions, as well as in the presence of Li, Na, Cs, Mg, and La nitrates. The Psi(0) (pCl) function was found to be linear within the experimental error and practically the same for all the examined electrolytes and almost independent of ionic strength. The reduction of the slope with respect to the Nernst equation, expressed by the alpha coefficient, was (0.88+/-0.01) at I(c)=10(-1) mol dm(-3), (0.87+/-0.01) at I(c)=10(-2) mol dm(-3), and (0.84+/-0.01) at I(c)=10(-3) mol dm(-3). The results were successfully interpreted by employing the surface complexation model developed originally for metal oxides and adapted for silver chloride. The standard ("intrinsic") equilibrium constants for the binding of chloride (K(o)(n)) and silver ions (K(o)(p)) on the corresponding sites at the silver chloride surface were evaluated as lg K(o)(n)=2.67+/-0.05; lg K(o)(p)=2.07+/-0.05. Counterion surface association equilibrium constants were also obtained as lg K(o)(NO3(-))=lg K(o)(K+)=274+/-0.05.

  13. Reactivity of OH radicals with chlorobenzoic acids—A pulse radiolysis and steady-state radiolysis study

    NASA Astrophysics Data System (ADS)

    Zona, Robert; Solar, Sonja; Getoff, Nikola; Sehested, Knud; Holcman, Jerzy

    2010-05-01

    The reactions of OH radicals with 2-, 3-, 4-chlorobenzoic acids (ClBzA) and chlorobenzene (ClBz), k( rad OH+substrates)=(4.5-6.2)×10 9 dm 3 mol -1 s -1, have been studied by pulse radiolysis in N 2O saturated solutions. The absorption maxima of the OH-adducts were in the range of 320-340 nm. Their decay was according to a second-order reaction, 2 k=(1-9)×10 8 dm 3 mol -1 s -1. In the presence of N 2O/O 2 the formation of peroxyl radicals was detectable for 2-, 4-ClBzA and ClBz, k(OH-adduct+O 2)=(2-4)×10 7 dm 3 mol -1 s -1, while this reaction for 3-ClBzA was too slow to be registered. In the presence of N 2O the degradation rates induced by gamma radiation were very similar for all chlorobenzoic acids, yet the chloride formation was distinctly higher for 3-ClBzA. In the presence of oxygen the initial degradation of 2-and 4-ClBzA equaled the OH-radical concentration, whereas in case of 3-ClBzA only ˜60% of rad OH led to degradation. The order for the efficiency of dehalogenation was 4->2->3-ClBzA. Several primary radiolytic products could be detected by HPLC. To evaluate the toxicity of final products a bacterial bioluminescence test was carried out.

  14. Hodin J. 2000. Plasticity and constraints in development and evolution. J exp zool (Mol dev evol) 288:1-20

    PubMed

    Kourakis; Martindale

    2000-08-15

    The sentences on page 8, in paragraph 2 of column 2 reads: In the short-germ insects, typified by Drosophila melanogaster, all the segments are specified nearly simultaneously in a noncellular, syncitial environment (reviewed in Lawrence, '92). By contrast, in the long-germ insects, typified by the grasshopper Schistocerca, the segments are specified in a gradual anterior-to-posterior progression in a cellular environment (reviewed in Patel, '94; Tautz et al., '94). The sentences should read: In the long-germ insects, typified by Drosophila melanogaster, all the segments are specified nearly simultaneously in a noncellular, syncitial environment (reviewed in Lawrence, '92). By contrast, in the short-germ insects, typified by the grasshopper Schistocerca, the segments are specified in a gradual anterior-to-posterior progression in a cellular environment (reviewed in Patel, '94; Tautz et al., '94). The terms "long-germ" and "short-germ" were reversed. The germ-type classification is key to the point being made in this paragraph: namely, showing that a similar-looking segmental plan can be formed by two rather different ontogenetic routes. The author regrets the error.

  15. VizieR Online Data Catalog: ExoMol line list for H218O and H2

    NASA Astrophysics Data System (ADS)

    Polyansky, O. L.; Kyuberis, A. A.; Lodi, L.; Tennyson, J.; Yurchenko, S. N.; Ovsyannikov, R. I.; Zobov, N. F.

    2017-01-01

    Two line lists HotWat78 are reported, for H2O-17 and H2O-18. Each line list is in two parts, a states file and transition file. The first contains a list of rovibrational states. Each state is labelled with 3 vibrational (v1, v2, v3), 3 rotational (J, Ka, Kc) quantum numbers and a total symmetry. "-2" indicates that the quantum numbers are not available. The total degeneracy is given to facilitate the intensity calculations. Because of their size, the transitions are listed in 30 separate files (for each molecule), each containing all the transitions in a 1000cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the highest frequency in the range and the isotopic number of oxygen; thus the a-060-17.dat file contains all the transitions of H2O17 in the frequency range 5000-6000cm-1 but not including 5000cm-1. The transition files a-xxxxxx.dat contain three columns: the reference number in the energy file of the upper state, that of the lower state and the Einstein A coefficient of the transition. The energy file and the transitions files are bzipped, and need to be extracted before use. We also provide the partition functions for each molecule in the range 0 to 6000K. (5 data files).

  16. Long-time aging in 3 mol.% yttria-stabilized tetragonal zirconia polycrystals at human body temperature.

    PubMed

    Keuper, Melanie; Berthold, Christoph; Nickel, Klaus Georg

    2014-02-01

    We present new findings on the low-temperature degradation of yttria-stabilized zirconia at 37°C over several years and at high and low partial pressures of water. With the aid of focused ion beam cross-section confirmation studies we are able to show an extensive linear, continuous degradation without retardation, even at low temperatures and low water pressures. The characteristic layer growth and its inferred rate constant imply a lifetime of tens of years under simple tension and open the possibility of studying the longevity of these ceramics more rigorously. In addition, we show reproducibility complications of accelerated aging tests by the use of different autoclaves and possible implications for standardized procedures.

  17. Test and evaluation of the one-meter, fuel rod calorimeter at Mol, Belgium, 1-12 June 1981

    SciTech Connect

    Rodenburg, W.W.; Keddar, A.

    1982-10-29

    In order to test the performance of the l-m fuel rod calorimeter, measurements were made of fuel rods with three different plutonium isotopic compositions containing from 3.6 to 28.5 g of plutonium. Measurement times were nominally 2 h: 1 h for a fuel rod measurement and 1 h for a base-line measurement. From these measurements, the precision (1 S.D.) of the calorimeter power measurement is 1 mW over the range of 10 to 135 mW. For rods with powers greater than 50 mW, apparent biases of up to 3% were within measured and assumed experimental errors. It is not possible from these data to identify the source of biases of -5.8% and -7% found for two rods. A problem encountered with the electric rod calibration requires further study. 1 figure, 7 tables.

  18. Temperature-dependent Sellmeier equation at terahertz frequency range for 1 mol % MgO-doped stoichiometric lithium tantalate

    NASA Astrophysics Data System (ADS)

    Lee, Kyu-Sup; Ko, Do-Kyeong; Yu, Nan Ei

    2017-04-01

    We first examined a temperature-dependent Sellmeier equation for the extraordinary refractive index of MgO-doped stoichiometric LiTaO3 (MgO:SLT) crystal via frequency-tunable narrowband terahertz (THz) generation at 0.4–1.8 THz and at a low temperature range of 80–300 K. The mean deviation of Sellmeier equation fit was less than 0.3%, being equivalent with the predicted measurement uncertainty of 0.3%. The temperature effect (dn THz/dT) was 2.02 × 10‑3/K at 1 THz. Moreover, we showed the smaller birefringence for MgO:SLT than MgO-doped stoichiometric LiNbO3 at 300 K from THz time-domain spectroscopy. This study is crucial for material study itself and THz device engineering.

  19. VizieR Online Data Catalog: ExoMol line list for H2S AYT2 (Yurchenko+, 2016)

    NASA Astrophysics Data System (ADS)

    Azzam, A. A. A.; Tennyson, J.; Yurchenko, S. N.; Naumenlo, O. V.

    2016-05-01

    The data are in two parts. The first, H2S_AYT2.dat contains a list of rovibrational states. Each state is labelled with 3 vibrational (v1, v2, v3) and 3 rotational (J, Ka, Kc) quantum numbers and total symmetry. An additional column indicates the source of the quantum numbers, empirical (e) or calculated (c). "---" (NaN) indicates that the quantum numbers are not available. The total degeneracy is given to facilitate the intensity calculations and the lifetimes (s) are given in the column 5. Because of their size, the transitions are listed in 20 separate files, each containing all the transitions in a 1000cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a_05000.dat file contains all the transitions in the frequency range 5000-6000cm-1 but not including 6000cm-1. The transition files a_xxxxx.dat contain three columns: the reference number in the energy file of the upper state, that of the lower state and the Einstein A coefficient of the transition. The energy file and the transitions files are bzipped, and need to be extracted before use. (2 data files).

  20. Observation des cycles enzymatiques des ADN topoisomérases par micromanipulation de molécules individuelles

    NASA Astrophysics Data System (ADS)

    Strick, Terence R.; Charvin, Gilles; Dekker, Nynke H.; Allemand, Jean-François; Bensimon, David; Croquette, Vincent

    In this article, we describe single-molecule assays using magnetic traps and we applied these assays to topoisomerase enzymes which unwind and disentangle DNA molecules. First, the elasticity of single DNA molecule is characterized using the magnetic trap. We show that a twisting constraint may be easily applied and that its effect upon DNA may be measured accurately. Then we describe how the topoisomerase activity may be observed at the single-molecule level giving direct access to the important biological parameters of the enzyme such as velocity and processivity. Furthermore, individual cycles of unwinding can be observed in real time. This permits an accurate characterization of the enzyme's biochemical cycle. The data treatment required to identify and analyze individual topoisomerization cycles will be presented in detail. This analysis is applicable to a wide variety of molecular motors. To cite this article: T.R. Strick et al., C. R. Physique 3 (2002) 595-618.

  1. VizieR Online Data Catalog: ExoMol line lists for H216O2 (Al-Refaie+, 2016)

    NASA Astrophysics Data System (ADS)

    Al-Refaie, A. F.; Polyansky, O. L.; Tennyson, J.; Yurchenko, S. N.

    2016-06-01

    The data are in two parts. The first, h2o20-85.dat contains a list of 7,560,352 rovibrational states. Each state is labelled with: six normal mode vibrational quantum numbers the torsional symmetry number (tau) and the vibrational symmetry; three rotational quantum numbers including the total angular momentum J and rotational symmetry; the total symmetry quantum number Gamma and the running number in the same J,Gamma block. In addition there are six local mode vibrational numbers and the largest coefficient used to assign the state in question. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The total degeneracy is also given to facilitate the intensity calculations. Because of their size, the transitions are listed in 60 separate files, each containing all the transitions in a 100cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-0500.dat file contains all the transitions in the frequency range 500-600cm-1. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, s_APTY.f90 which may be used to generate synthetic spectra (see s_APTY.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else cross-sections convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Sample input files s*.inp for use with sAPTY.f90 are supplied. (10 data files).

  2. VizieR Online Data Catalog: ExoMol line lists for formaldehyde H2CO (Al-Refaie+,

    NASA Astrophysics Data System (ADS)

    Al-Refaie, A. F.; Yachmenev, A.; Tennyson, J.; Yurchenko, S. N.

    2015-01-01

    The data are in two parts. The first, h2co_0-70.dat contains a list of 10,296,998 rovibrational states. Each state is labelled with: 6 normal mode vibrational quantum numbers, and the vibrational symmetry; three rotational quantum numbers including the total angular momentum J, the projection of J in the z-axis K,rotational symmetry and the total symmetry quantum number Gamma In addition there are six local mode vibrational numbers and the largest coeffecient used to assign the state in question. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The total degeneracy is also given to facilitate the intensity calculations. Because of their size, the transitions are listed in 100 separate files, each containing all the transitions in a 100cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-00500.dat file contains all the transitions in the frequency range 500-600cm-1. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, s_AYTY.f90 which may be used to generate synthetic spectra (see s_AYTY.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else cross-sections convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Sample input files s*.inp for use with sSAlTY.f90 are supplied. (9 data files).

  3. VizieR Online Data Catalog: ExoMol line lists for phosphine (PH3) (Sousa-Silva+,

    NASA Astrophysics Data System (ADS)

    Sousa-Silva, C.; Al-Refaie, A. F.; Tennyson, J.; Yurchenko, S. N.

    2014-11-01

    The data are in two parts. The first, ph3_0-46.dat contains a list of 9,787,832 rovibrational states. Each state is labelled with: 6 normal mode vibrational quantum numbers, 1 multiplexed L quantum number and the vibrational symmetry; three rotational quantum numbers including the total angular momentum J, the projection of J in the z-axis K,rotational symmetry and the total symmetry quantum number Gamma In addition there are nine local mode vibrational numbers and the largest coefficient used to assign the state in question. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. The total degeneracy is also given to facilitate the intensity calculations. Because of their size, the transitions are listed in 100 separate files, each containing all the transitions in a 100cm-1 frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-00500.dat file contains all the transitions in the frequency range 500-600cm-1. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, s_SAlTY.f90 which may be used to generate synthetic spectra (see s_SAlTY.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else cross-sections convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Sample input files s*.inp for use with sSAlTY.f90 are supplied. (10 data files).

  4. ExoMol molecular line lists - XVI. The rotation-vibration spectrum of hot H2S

    NASA Astrophysics Data System (ADS)

    Azzam, Ala'a. A. A.; Tennyson, Jonathan; Yurchenko, Sergei N.; Naumenko, Olga V.

    2016-08-01

    This work presents the AYT2 line list: a comprehensive list of 115 million 1H232S vibration-rotation transitions computed using an empirically adjusted potential energy surface and an ab initio dipole moment surface. The line list gives complete coverage up to 11 000 cm-1 (wavelengths longer than 0.91 μm) for temperatures up to 2000 K. Room temperature spectra can be simulated up to 20 000 cm-1 (0.5 μm) but the predictions at visible wavelengths are less reliable. AYT2 is made available in electronic form as supplementary data to this paper at www.exomol.com.

  5. Broad Temperature Pinning Study of 15 mol.% Zr-Added (Gd, Y)-Ba-Cu-O MOCVD Coated Conductors

    SciTech Connect

    Xu, AX; Khatri, N; Liu, YH; Majkic, G; Galstyan, E; Selvamanickam, V; Chen, YM; Lei, CH; Abraimov, D; Hu, XB; Jaroszynski, J; Larbalestier, D

    2015-06-01

    BaZrO3 (BZO) nanocolumns have long been shown to be very effective for raising the pinning force F-p of REBa2Cu3Ox (REBCO, where RE = rare earth) films at high temperatures and recently at low temperatures too. We have successfully incorporated a high density of BZO nanorods into metal organic chemical vapor deposited (MOCVD) REBCO coated conductors via Zr addition. We found that, compared to the 7.5% Zr-added coated conductor, dense BZO nanorod arrays in the 15% Zr-added conductor are effective over the whole temperature range from 77 K down to 4.2 K. We attribute the substantially enhanced J(c) at 30 K to the weak uncorrelated pinning as well as the strong correlated pinning. Meanwhile, by tripling the REBCO layer thickness to similar to 2.8 mu m, the engineering critical current density J(e) at 30 K exceeds J(e) of optimized Nb-Ti wires at 4.2 K.

  6. Threshold Photoelectron Photoion Coincidence (TPEPICO) Studies. The Road to ± 0.1 kJ/mol Thermochemistry

    SciTech Connect

    Baer, Tomas

    2013-10-14

    The threshold photoelectron photoion coincidence (TPEPICO) technique is utilized to investigate the dissociation dynamics and thermochemistry of energy selected medium to large organic molecular ions. The reactions include parallel and consecutive steps that are modeled with the statistical theory in order to extract dissociation onsets for multiple dissociation paths. These studies are carried out with the aid of molecular orbital calculations of both ions and the transition states connecting the ion structure to their products. The results of these investigations yield accurate heats of formation of ions, free radicals, and stable molecules. In addition, they provide information about the potential energy surface that governs the dissociation process. Isomerization reactions prior to dissociation are readily inferred from the TPEPICO data.

  7. The Potential of Algarrobo ( Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions

    NASA Astrophysics Data System (ADS)

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75 % germination at 300 mM NaCl, followed by 50 % germination at 450 mM NaCl and 30 % germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97 % at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils.

  8. mtsslSuite: In silico spin labelling, trilateration and distance-constrained rigid body docking in PyMOL

    NASA Astrophysics Data System (ADS)

    Hagelueken, Gregor; Abdullin, Dinar; Ward, Richard; Schiemann, Olav

    2013-10-01

    Nanometer distance measurements based on electron paramagnetic resonance methods in combination with site-directed spin labelling are powerful tools for the structural analysis of macromolecules. The software package mtsslSuite provides scientists with a set of tools for the translation of experimental distance distributions into structural information. The package is based on the previously published mtsslWizard software for in silico spin labelling. The mtsslSuite includes a new version of MtsslWizard that has improved performance and now includes additional types of spin labels. Moreover, it contains applications for the trilateration of paramagnetic centres in biomolecules and for rigid-body docking of subdomains of macromolecular complexes. The mtsslSuite is tested on a number of challenging test cases and its strengths and weaknesses are evaluated.

  9. ReefMedMol: Mollusca from the infralittoral rocky shores - the biocoenosis of photophilic algae - in the Mediterranean Sea.

    PubMed Central

    Koutsoubas, Drosos; Arvanitidis, Christos; Chatzigeorgiou, Giorgos

    2016-01-01

    Abstract Background This paper describes two datasets on the molluscan fauna from the Mediterranean infralittoral reef ecosystem - the biocoenosis of photophilic algae. The first dataset is taken from the East Mediterranean node of the NAGISA project. The second one is a compilation based on the available published material in peer - reviewed journals as well as from the accessible grey literature. These datasets cover a time period of 43 years from 1969 to 2012 from several locations spanning the Mediterranean Sea. New information This dataset is the only one available from this important Mediterranean Habitat, coded as 1170 in the Habitats Directive (92/43/EEC) and can provide valuable information on the needs of ecosystems functions and services assessment, habitat and species conservation as well as marine spatial planning. PMID:27932901

  10. The Potential of Algarrobo (Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions.

    PubMed

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75% germination at 300 mM NaCl, followed by 50% germination at 450 mM NaCl and 30% germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97% at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils.

  11. [Use of algarrobo (Prosopis chilensis (Mol) Stuntz) flour as protein and dietary fiber source in cookies and fried chips manufacture].

    PubMed

    Escobar, Berta; Estévez, Ana María; Fuentes, Carolina; Venegas, Daniela

    2009-06-01

    Limiting amino acids of the protein from chilean "algarrobo" are isoleucine, theronine and methionine/cyteine. Cereals and legume blends allow to improve the amino acid balance, since legume have more lysine, and cereals are richer in sulphur amino acids. Due to the nutritional interest of "algarrobo" cotyledons, the use of "algarrobo cotyledon" flour (ACF) in sweet and salty snack manufacture was evaluated. Cookies and fried salty chips with 0%, 10% and 20% ACF were prepared. Flours were analyzed for color, particle size, moisture, proximate composition, available lysine, and soluble, insoluble and total dietary fiber. Cookies and chips were analyzed for the same characteristics (except for particle size); besides there were determined water activity, weight and size of the units, and also, the caloric value was computed. Sensory quality and acceptance of both products were evaluated. It is noticeable the high amount of protein, lipids, ash, crude fiber (63.6; 10.2; 4.3 and 4.2 g/100 g dmb, respectively), available lysine (62.4 mg/g protein) and total dietary fiber (24.2 g/100 g dmb) of ACF. Both, cookies and chips with ACF, showed a significant increase in the amount of protein, lipids, ash, crude fiber and, available lysine (from 15.5 to 19,3 and from 20.3 a 29.6 mg lisina/g protein, respectively), and total dietary fiber (from 1.39 to 2.80 and from 1.60 a 5.60 g/100 g dmb, respectively). All of the cookies trials were well accepted ("I like it very much"); chips with 10% of AFC showed the highest acceptance ("I like it"). It can be concluded that the use of ACF in cookies and chips manufacture increases the contribution of available lysine; their protein and dietary fiber content, improving the soluble/insoluble fiber ratio, without affect neither their physical nor their sensory acceptance.

  12. VizieR Online Data Catalog: ExoMol line list for phosphorus nitride (PN) (Yorke+, 2014)

    NASA Astrophysics Data System (ADS)

    Yorke, L.; Yurchenko, S. N.; Lodi, L.; Tennyson, J.

    2014-09-01

    The data are in two parts: .states contain lists of rovibrational states of PN. Each state is labelled with the total angular momentum J and the vibrational quantum number v and represented by a unique number, which is the number of the row in which it appears in the .states file. This number is the means by which the state is related to the second part of the data system, the transitions files. The total degeneracy is also given to facilitate the intensity calculations. The transition files .trans contain transitions given by three columns: the reference number in the energy file of the upper state for the isotopologue in question; that of the lower state; and the Einstein A coefficient of the transition. The transitions ordered by increasing frequency. There is a Fortran 90 programme, spectrum_exomol.f90 which may be used to generate synthetic spectra (see spectrum_exomol.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else cross-sections convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Sample input files with spectrum_exomol.f90 are supplied. (11 data files).

  13. Critical effect of cubic phase on aging in 3mol% yttria-stabilized zirconia ceramics for hip replacement prosthesis.

    PubMed

    Chevalier, Jérôme; Deville, Sylvain; Münch, Etienne; Jullian, Romain; Lair, Frédéric

    2004-11-01

    The isothermal tetragonal-to-monoclinic transformation of 3Y-TZP ceramics sintered at two different temperatures (1450 degrees C and 1550 degrees C) and duration (2 and 5h) is investigated at 134 degrees C in steam. Particular attention is paid to the presence of a cubic phase and its effect on isothermal aging. Sintering at 1550 degrees C can result in a significant amount of large cubic grains in the specimens, that have a detrimental impact on aging resistance, especially for the first stage of the aging process. Cubic grains appear to be enriched in yttrium, which in turn leads to a depletion of yttrium in the neighboring tetragonal grains. These grains will act as nucleation sites for tetragonal-to-monoclinic transformation. Even for specimens sintered at lower temperature, i.e. 1450 degrees C, the presence of a cubic phase is expected from the phase diagram, leading to a significant effect on aging sensitivity.

  14. [The determination of glucose, sucrose and fructose by the method of capillary electrophoresis].

    PubMed

    Yakuba, Yu F; Markovsky, M G

    2015-01-01

    The possibilities of different regimes of micellar capillary electrophoresis using negative polarity and alkaline electrolyte for determination of glucose, sucrose, fructose in extracts of vegetative organs of plants and products of fruits and grapes processing have been studied. A comparative evaluation of the limits of detection of glucose, sucrose, fructose for developed electrolytes have been performed, the advantages and disadvantages of techniques have been discussed. It is recommended to use an aqueous electrolyte containing 0.5% potassium sorbate, 0.62% cetyltrimethylammonium bromide, and 0.02% potassium hydroxide. The analyzed components were detected at 254 nm. The sample was dosed hydrodynamically (30 mbar, 5 sec). Negative voltage 16 kV is recommended, current--54 ± 4 µA, capillary thermostating at 24 °C is applied, the analysis time--15 min. The detection limits for fructose and glucose is 0.03 g/dm3 to 0.07 g of sucrose/dm3. Linearity is stored for each component to 5.0 g/dm 3 inclusive. Electrophoretic mobility of carbohydrates was (10(-4) sm2V(-1)sec(-1)): fructose--3.12, glucose--3.03, sucrose--2.74. Approximate time of release: glucose--13 min, sucrose--13.5 min, fructose--12.5 min. The developed options for mass concentration determining of mono- and disaccharides provide complete separation of the components. Anions, glycerol, ethylene glycol, propylene glycol and butylene isomers do not affect the analysis results.

  15. Fast repair of thymine-hydroxyl radical adduct by phenylpropanoid glycosides

    NASA Astrophysics Data System (ADS)

    Wenyan, Li; Zhihua, Zou; Rongliang, Zheng; Changzeng, Wang; Zhongjian, Jia; Side, Yao; Nianyun, Lin

    1997-04-01

    The repair effect on thymine-hydroxyl adduct by phenylpropanoid glycosides (PPG): verbascoside, and pedicularioside A, isolated from Pedicularis, were studied using pulse radiolysis technique. From the analysis of transient absorption spectra, the rapid electron transfer from PPG to T-OH - was observed. Phenoxyl radical of PPG were generated via one-electron-transfer reaction. This result showed that two PPG exhibited repair activities on oxidizing T-OH -. The reaction rate constants of electron transfer from PPGs were 1.27 × 10 9 and 1.29 × 10 9 dm 3·mol -1s -1 respectively.

  16. Effect of carboxymethyl cellulose and ionic strength on stability of mineral suspensions in potash ore flotation systems.

    PubMed

    Pawlik, M; Laskowski, J S; Ansari, A

    2003-04-15

    The adsorption of sodium carboxymethyl cellulose from aqueous solutions varying in ionic strength from that of distilled water to 50% NaCl/KCl brine (about 3.5 mol/dm(3)) onto illite and dolomite has been studied. The purpose of this work was to investigate the solvency effects in the phenomena underlying the potash flotation process that is carried out in saturated brine. Based on viscosity measurements, the adsorption results were analyzed in terms of a simple model of polymer macromolecules in solution. Suspension stability measurements carried out concomitantly with adsorption tests showed the ranges of carboxymethyl cellulose concentration over which the tested suspensions either were aggregated or were restabilized.

  17. A new potent inhibitor of horse liver alcohol dehydrogenase: p-methylbenzyl hydroperoxide.

    PubMed

    Skurský, L; Khan, A N; Saleem, M N; al-Tamer, Y Y

    1992-04-01

    A product of p-xylene auto-oxidation, p-methylbenzyl hydroperoxide, acts as a very strong reversible inhibitor of the ethanol dehydrogenating activity of horse liver alcohol dehydrogenase. Concentrations of hydroperoxide as low as that of the enzyme active site (about 10(-8) mol.dm-3) in the assay depresses the activity by 50%. Somewhat less potent is benzyl hydroperoxide (derived from toluene) while the (secondary) hydroperoxide derived from ethylbenzene and tert.butyl hydroperoxide and cumyl hydroperoxide do not inhibit HLAD appreciably.

  18. Oxidative study of gabapentin by alkaline hexacyanoferrate(III) in room temperature in presence of catalytic amount of Ru(III) a mechanistic approach

    NASA Astrophysics Data System (ADS)

    Jose, Timy P.; Angadi, Mahantesh A.; Salunke, Manjalee S.; Tuwar, Suresh M.

    2008-12-01

    The kinetics of oxidation of gabapentin by hexacyanoferrate(III) in aqueous alkaline medium at a constant ionic strength of 0.5 mol dm -3 was studied spectrophotometrically. The reaction is of first order in [HCF(III)] and of less than unit order in [alkali]. The reaction rate is independent upon [gabapentin]. Effects of added products, ionic strength and dielectric constant of the reaction medium have been investigated. Oxidative product of gabapentin was identified. A suitable mechanism has been proposed. The reaction constants involved in the different steps of mechanism are calculated. The activation parameters of the mechanism are computed and discussed .

  19. Hydroxyl radical induced oxidation of theophylline in water: a kinetic and mechanistic study.

    PubMed

    Sunil Paul, M M; Aravind, U K; Pramod, G; Saha, A; Aravindakumar, C T

    2014-08-14

    Oxidative destruction and mineralization of emerging organic pollutants by hydroxyl radicals (˙OH) is a well established area of research. The possibility of generating hazardous by-products in the case of ˙OH reaction demands extensive investigations on the degradation mechanism. A combination of pulse radiolysis and steady state photolysis (H2O2/UV photolysis) followed by high resolution mass spectrometric (HRMS) analysis have been employed to explicate the kinetic and mechanistic features of the destruction of theophylline, a model pharmaceutical compound and an identified pollutant, by ˙OH in the present study. The oxidative destruction of this molecule, for intermediate product studies, was initially achieved by H2O2/UV photolysis. The transient absorption spectrum corresponding to the reaction of ˙OH with theophylline at pH 6, primarily caused by the generation of (T8-OH)˙, was characterised by an absorption band at 330 nm (k2 = (8.22 ± 0.03) × 10(9) dm(3) mol(-1) s(-1)). A significantly different spectrum (λmax: 340 nm) was observed at highly alkaline pH (10.2) due to the deprotonation of this radical (pKa∼ 10.0). Specific one electron oxidants such as sulphate radical anions (SO4˙(-)) and azide radicals (N3˙) produce the deprotonated form (T(-H)˙) of the radical cation (T˙(+)) of theophylline (pKa 3.1) with k2 values of (7.51 ± 0.04) × 10(9) dm(3) mol(-1) s(-1) and (7.61 ± 0.02) × 10(9) dm(3) mol(-1) s(-1) respectively. Conversely, oxide radicals (O˙(-)) react with theophylline via a hydrogen abstraction protocol with a rather slow k2 value of (1.95 ± 0.02) × 10(9) dm(3) mol(-1) s(-1). The transient spectral studies were complemented by the end product profile acquired by HRMS analysis. Various transformation products of theophylline induced by ˙OH were identified by this technique which include derivatives of uric acids (i, iv & v) and xanthines (ii, iii & vi). Further breakdown of the early formed product due to ˙OH attack leads to

  20. Structural properties of aqueous metoprolol succinate solutions. Density, viscosity, and refractive index at 311 K

    NASA Astrophysics Data System (ADS)

    Deosarkar, S. D.; Kalyankar, T. M.

    2013-06-01

    Density, viscosity and refractive index of aqueous solutions of metoprolol succinate of different concentrations (0.005-0.05 mol dm-3) were measured at 38°C. Apparent molar volume of resultant solutions were calculated and fitted to the Masson's equation and apparent molar volume at infinite dilution was determined graphically. Viscosity data of solutions has been fitted to the Jone-Dole equation and viscosity A- and B-coefficients were determined graphically. Physicochemical data obtained were discussed in terms of molecular interactions.

  1. The effect of lead on the photoelectric reaction of Zea mays L. plants.

    PubMed

    Pazurkiewicz-Kocot, K; Pietruszka, M

    2000-09-01

    We investigate the correlation between the concentrations of lead (10(-6)-10(-2) mol dm(-3) PbCl2) in the external medium and photoelectric reaction of Zea mays L. plants. The experiments were carried out on 8-10-day-old maize plants (Zea mays L. var. K33 x F2) with the use of conventional electrophysiological technique. The results suggest that in plants treated with lead ions the photoelectric reaction is significantly reduced. The pH variation of the incubation medium including the green fragments of leaves showed that lead ions caused inhibition of light-induced external acidification.

  2. Ion-solvent and ion-ion interactions of NaCl aqueous and aqueous maltose solutions at 298-323 K on viscosity data

    NASA Astrophysics Data System (ADS)

    Masood, Summyia; Saeed, Rehana; Ashfaq, Maria; Irfan, Afshan

    2014-12-01

    Viscosities of sodium chloride in concentration range 1 × 10-2 to 9 × 10-2 ± 0.001 mol dm-3, have been determined in aqueous and aqueous maltose systems (1.0 to 9.0 wt %) at different temperatures (298 to 323 K). The viscosity data have been analyzed by using Jones-Dole equation and the derived parameters A and B coefficients were also calculated. The data obtained from viscometric studies has been used to investigate the ion-solvent interaction and ion-ion interaction. Thermal effects on the ionic interactions were also examined under the light of transition state theory.

  3. Chemical properties and toxicity of soils contaminated by mining activity.

    PubMed

    Agnieszka, Baran; Tomasz, Czech; Jerzy, Wieczorek

    2014-09-01

    This research is aimed at assessing the total content and soluble forms of metals (zinc, lead and cadmium) and toxicity of soils subjected to strong human pressure associated with mining of zinc and lead ores. The research area lay in the neighbourhood of the Bolesław Mine and Metallurgical Plant in Bukowno (Poland). The study obtained total cadmium concentration between 0.29 and 51.91 mg, zinc between 7.90 and 3,614 mg, and that of lead between 28.4 and 6844 mg kg(-1) of soil d.m. The solubility of the heavy metals in 1 mol dm(-3) NH4NO3 was 1-49% for zinc, 5-45% for cadmium, and <1-10% for lead. In 1 mol HCl dm(-3), the solubility of the studied metals was much higher and obtained values depending on the collection site, from 45 to 92% for zinc, from 74 to 99%, and from 79 to 99% for lead. The lower solubility of the heavy metals in 1 mol dm(-3) NH4NO3 than 1 mol HCl dm(-3) is connected with that, the ammonium nitrate has low extraction power, and it is used in determining the bioavailable (active) form of heavy metals. Toxicity assessment of the soil samples was performed using two tests, Phytotoxkit and Microtox(®). Germination index values were between 22 and 75% for Sinapis alba, between 28 and 100% for Lepidium sativum, and between 10 and 28% for Sorghum saccharatum. Depending on the studied soil sample, Vibrio fischeri luminescence inhibition was 20-96%. The sensitivity of the test organisms formed the following series: S. saccharatum > S. alba = V. fischeri > L. sativum. Significant positive correlations (p ≤ 0.05) of the total and soluble contents of the metals with luminescence inhibition in V. fischeri and root growth inhibition in S. saccharatum were found. The general trend observed was an increase in metal toxicity measured by the biotest with increasing available metal contents in soils. All the soil samples were classified into toxicity class III, which means that they are toxic and present severe danger. Biotest are a good complement to

  4. Spectrophotometric determination of copper(II) with o-bromophenylfluorone.

    PubMed

    Yamaguchi, Takako; Samma, Megumi; Kamino, Shinichiro; Matsushita, Momoka; Hashimoto, Tomoyuki; Fujita, Yoshikazu

    2009-12-01

    A simple, reliable and sensitive spectrophotometric method for the determination of copper(II) was established with o-bromophenylfluorone (OBPF), a novel chemical probe, in the presence of poly(N-vinylpyrrolidone). Beer's law was obeyed in the range of 8-160 ng ml(-1), with an apparent molar absorptivity at 570 nm, the relative standard deviation being 3.64 x 10(5) dm3 mol(-1) cm(-1) and 0.72% (n = 5). This method was applied to the recovery tests of copper(II) in human urine, bovine serum and tap water; the results were satisfactory.

  5. Pore size dependent behavior of hydrated Ag+ ions confined in mesoporous MCM-41 materials under synchrotron X-ray irradiation.

    PubMed

    Ito, Kanae; Yoshida, Koji; Kittaka, Shigeharu; Yamaguchi, Toshio

    2012-01-01

    The behavior of hydrated Ag+ ions in a 1.5 mol dm(-3) AgNO3 aqueous solution confined in mesoporous silica MCM-41 with different pore sizes was characterized by synchrotron X-ray absorption spectroscopy. The hydrated Ag+ ions are stabilized in 4-fold coordination down to 195 K in the pores (21 Å in diameter), whereas in the larger pores (28 Å) the hydrated Ag+ ions are reduced to Ag0 to form nano clusters with the Ag-Ag interactions of 2.80 Å.

  6. A search for temperature induced time-dependent structural transitions in 10mol%Sc2O3–1mol%CeO2–ZrO2 and 8mol%Y2O3–ZrO2 electrolyte ceramics

    DOE PAGES

    Chen, Yan; Orlovskaya, Nina; Payzant, E. Andrew; ...

    2014-11-08

    Both Sc2O3–CeO2-stabilized-ZrO2 (SCSZ) and Y2O3-stabilized-ZrO2 (YSZ) show similar Young's modulus damping at 175–400 °C and 200–400 °C, respectively, by impulse excitation acoustic technique. The phase transition in SCSZ is considered responsible for the damping; however for YSZ, such a phase transition has never been reported. To clarify the relation of damping and structural transition in these two materials, the time-dependent high temperature stabilities are studied by in situ X-ray diffraction, neutron diffraction and Raman scattering during long-term annealing of SCSZ at 350 °C and YSZ at 275 °C. The cubic-to-rhombohedral transition in SCSZ is detected. However, the existence of t'more » phase in YSZ raw powders is confirmed without significant changes of the cubic structure during isothermal annealing. It is concluded that the phase transition contributes to the Young's modulus damping in SCSZ, while the structural transition is excluded from the reason for damping in YSZ.« less

  7. A search for temperature induced time-dependent structural transitions in 10mol%Sc2O3–1mol%CeO2–ZrO2 and 8mol%Y2O3–ZrO2 electrolyte ceramics

    SciTech Connect

    Chen, Yan; Orlovskaya, Nina; Payzant, E. Andrew; Graule, Thomas; Kuebler, Jakob

    2014-11-08

    Both Sc2O3–CeO2-stabilized-ZrO2 (SCSZ) and Y2O3-stabilized-ZrO2 (YSZ) show similar Young's modulus damping at 175–400 °C and 200–400 °C, respectively, by impulse excitation acoustic technique. The phase transition in SCSZ is considered responsible for the damping; however for YSZ, such a phase transition has never been reported. To clarify the relation of damping and structural transition in these two materials, the time-dependent high temperature stabilities are studied by in situ X-ray diffraction, neutron diffraction and Raman scattering during long-term annealing of SCSZ at 350 °C and YSZ at 275 °C. The cubic-to-rhombohedral transition in SCSZ is detected. However, the existence of t' phase in YSZ raw powders is confirmed without significant changes of the cubic structure during isothermal annealing. It is concluded that the phase transition contributes to the Young's modulus damping in SCSZ, while the structural transition is excluded from the reason for damping in YSZ.

  8. Initial laboratory and sky testing results for the second generation H4RG-10 4k x 4k, 10 micron visible CMOS-Hybrid detector

    NASA Astrophysics Data System (ADS)

    Dorland, Bryan N.; Dudik, Rachel P.; Veillette, Dan; Swindle, Ryan; Waczynski, Augustyn; Kan, Emily

    2009-08-01

    We present the initial performance test results for the H4RG-10 (A2), the second generation of the H4RG-10 visible CMOS-Hybrid Sensor Chip Assembly (SCA). The first science grade H4RG-10 (A2), delivered in 2009, is an evolution of the first generation A1, first delivered and tested in 2007. The H4RG-10 is primarily intended for ground- and space-based astronomical applications. Our evaluation focused on the performance parameters as they are related to astrometric applications. We find that the A2 SCA shows high pixel interconnect (99.6%), and low read noise (10-15 e- RMS) when operated at high speeds, consistent with A1 results. Most importantly, the H4RG-10 (A2) shows a dramatic improvement in dark current vs. the A1, with a two order of magnitude reduction in mean dark level and significantly reduced hot pixel population below 200 K.

  9. Initial Laboratory and Sky Testing Results for the Second Generation H4RG-10 4k x 4k, 10 Micron Visible CMOS-Hybrid Detector

    DTIC Science & Technology

    2009-01-01

    Initial Laboratory and Sky Testing Results for tbe Second Generation H4RG -I0 4k x 4k, 10 micron visible CMOS-Hybrid Detector Bryan N. Dorland,a...results for the H4RG·IO (A2), the second generation orlhe H4RG -IO visible CMOS-Hybrid Sensor Chip Assembly (SeA). The lirst science grade H4RG - JO (A2...delivered in 2009, is an evolution of the first generation A I, fi rst delivered and tested in 2007. The H4RG - 10 is primarily intended for

  10. Laboratory and sky testing results for the TIS H4RG-10 4k × 4k 10-micron visible CMOS-hybrid detector

    NASA Astrophysics Data System (ADS)

    Dorland, Bryan N.; Hennessy, Gregory S.; Zacharias, Norbert; Monet, David G.; Harris, Hugh; Rollins, Chris; Shu, Peter; Miko, Laddawan; Mott, Brent; Waczynski, Augustyn; Kan, Emily; Delo, Gregory

    2007-09-01

    We present both laboratory and telescope testing results describing the performance of the H4RG-10 CMOS-Hybrid detector. The H4RG-10 is the largest visible hybrid array currently in existence and shows great potential for use in future space missions. We report read noise, dark current, pixel connectivity, persistence, and inter-pixel capacitance measurements for the temperature range 110-240 K. We report on quantitative astrometric and qualitative photometric performance of the instrument based on observations made at USNO's Flagstaff Station observatory and establish an upper limit to the astrometric performance of the detector. We discuss additional testing and future work associated with improving detector performance.

  11. Line intensities and temperature-dependent line broadening coefficients of Q-branch transitions in the v2 band of ammonia near 10.4 μm

    NASA Astrophysics Data System (ADS)

    Sur, Ritobrata; Spearrin, R. Mitchell; Peng, Wen Y.; Strand, Christopher L.; Jeffries, Jay B.; Enns, Gregory M.; Hanson, Ronald K.

    2016-05-01

    We report measured line intensities and temperature-dependent broadening coefficients of NH3 with Ar, N2, O2, CO2, H2O, and NH3 for nine sQ(J,K) transitions in the ν2 fundamental band in the frequency range 961.5-967.5 cm-1. This spectral region was chosen due to the strong NH3 absorption strength and lack of spectral interference from H2O and CO2 for laser-based sensing applications. Spectroscopic parameters were determined by multi-line fitting using Voigt lineshapes of absorption spectra measured with two quantum cascade lasers in thermodynamically-controlled optical cells. The temperature dependence of broadening was measured over a range of temperatures between 300 and 600 K. These measurements aid the development of mid-infrared NH3 sensors for a broad range of gas mixtures and at elevated temperatures.

  12. Effects of Ti(IV) substitution on protein adsorption behaviors of calcium hydroxyapatite particles.

    PubMed

    Kandori, Kazuhiko; Oketani, Makoto; Wakamura, Masato

    2013-01-01

    The fundamental experiments on the adsorption behaviors of proteins onto photocatalytic Ti(IV)-doped calcium hydroxyapatite (TiHap) particles with varied amounts of Ti(IV) ions doped (called as original particle) were examined comparing to those onto the calcium hydroxyapatite (CaHap) ones. The heat treated TiHaps and CaHap particles at 650°C for 1h were also examined (called as heat treated particle). The Ti/(Ca+Ti) atomic ratio (X(Ti)) of the TiHap particles was varied between 0 and 0.20. Since the surface acidity of the particles was increased by increase in X(Ti) value, the negative zeta potential (zp) of the particles was increased. All the adsorption isotherms of bovine serum albumin (BSA), myoglobin (MGB) and lysozyme (LSZ) from 1×10(-4)mol/dm(3) KCl solution were the pseudo-Langmuirian type. The saturated amounts of adsorbed LSZ (n(S)(LSZ)) values onto the original particles were increased with increase in the negative zp of the particles. However, the saturated amounts of adsorbed BSA (n(S)(BSA)) values were decreased by increase in the negative zp except at X(Ti)=0.05 where n(S)(BSA) value exhibited a maximum. In the case of MGB, the saturated amounts of adsorbed MGB (n(s)(MGB)) values were less dependent on the zp of the particles. These results were explained by changing the electrostatic forces between protein molecules and TiHap particles by doping Ti(IV) ions. On the other hand, n(S)(BSA), n(S)(LSZ) and n(s)(MGB) values onto the heat treated particles were larger than the original particles in each particle system, though no relationship to the X(Ti) value was recognized in each protein system. This result was interpreted to the formation of β-TCP crystal phase in both the CaHap and TiHap particles by the heat treatment. The Ca(2+) ions produced by dissolution from β-TCP phase may exert as binders between BSA and surfaces of the heat treated particles. The weak binder effects of Ca(2+) and PO(4)(3-) ions were observed for the adsorptions of LSZ

  13. Protein adsorption behaviors onto photocatalytic Ti(IV)-doped calcium hydroxyapatite particles.

    PubMed

    Kandori, Kazuhiko; Kuroda, Tomohiko; Wakamura, Masato

    2011-10-15

    The fundamental experiments on the adsorption behaviors of proteins onto photocatalytic Ti(4+)-doped calcium hydroxyapatite (TiHap) particles were examined comparing to those onto the calcium hydroxyapatite (CaHap) and commercially available typical titanium oxide (TiO(2)) photocatalyst (TKP-101). The heat treated TiHap and CaHap particles were also used after treated these particles at 650°C for 1h (abbreviated as TiHap650 and CaHap650, respectively). All the adsorption isotherms of bovine serum albumin (BSA), myoglobin (MGB) and lysozyme (LSZ) from 1×10(-4)mol/dm(3) KCl solution were the Langmuirian type. The saturated amounts of adsorbed BSA (n(s)(BSA)) for the CaHap650 particles was higher than that for CaHap. Similar results were observed for TiHap and TiHap650. The adsorption of LSZ exhibited the same result of BSA, while the saturated amounts of adsorbed LSZ (n(s)(LSZ)) value on the TiHap were much higher than CaHap. However, the saturated amounts of adsorbed MGB (n(s)(MGB)) are almost equal to those for the CaHap and TiHap nevertheless whether these particles were heat treated at 650°C or not. The TKP-101 exhibited extremely small adsorption capacity of all proteins due to its small particle size of ca. 4nm in diameter. The independence of the n(s)(MGB) value on the zeta potential (zp) of the particles was explained by the electrostatical neutrality of MGB molecules. On the other hand, the n(s)(LSZ) values were increased with increase in the negative zp of the particles. This fact was explained by increasing the electrostatic attractive forces between negatively charged particles and positively charged LSZ. However, the n(s)(BSA) values exhibit maxima for the heat treated TiHap650 and CaHap650 particles. This result was interpreted to the formation of β-TCP crystal phase by the heat treatment. The produced Ca(2+) ions by dissolution from β-TCP phase may exert as binders between BSA and surfaces of the heat treated particles.

  14. In vitro kinetic studies on the mechanism of oxygen-dependent cellular uptake of copper radiopharmaceuticals

    NASA Astrophysics Data System (ADS)

    Holland, Jason P.; Giansiracusa, Jeffrey H.; Bell, Stephen G.; Wong, Luet-Lok; Dilworth, Jonathan R.

    2009-04-01

    The development of hypoxia-selective radiopharmaceuticals for use as therapeutic and/or imaging agents is of vital importance for both early identification and treatment of cancer and in the design of new drugs. Radiotracers based on copper for use in positron emission tomography have received great attention due to the successful application of copper(II) bis(thiosemicarbazonato) complexes, such as [60/62/64Cu(II)ATSM] and [60/62/64Cu(II)PTSM], as markers for tumour hypoxia and blood perfusion, respectively. Recent work has led to the proposal of a revised mechanism of hypoxia-selective cellular uptake and retention of [Cu(II)ATSM]. The work presented here describes non-steady-state kinetic simulations in which the reported pO2-dependent in vitro cellular uptake and retention of [64Cu(II)ATSM] in EMT6 murine carcinoma cells has been modelled by using the revised mechanistic scheme. Non-steady-state (NSS) kinetic analysis reveals that the model is in very good agreement with the reported experimental data with a root-mean-squared error of less than 6% between the simulated and experimental cellular uptake profiles. Estimated rate constants are derived for the cellular uptake and washout (k1 = 9.8 ± 0.59 × 10-4 s-1 and k2 = 2.9 ± 0.17 × 10-3 s-1), intracellular reduction (k3 = 5.2 ± 0.31 × 10-2 s-1), reoxidation (k4 = 2.2 ± 0.13 mol-1 dm3 s-1) and proton-mediated ligand dissociation (k5 = 9.0 ± 0.54 × 10-5 s-1). Previous mechanisms focused on the reduction and reoxidation steps. However, the data suggest that the origins of hypoxia-selective retention may reside with the stability of the copper(I) anion with respect to protonation and ligand dissociation. In vitro kinetic studies using the nicotimamide adenine dinucleotide (NADH)-dependent ferredoxin reductase enzyme PuR isolated from the bacterium Rhodopseudomonas palustris have also been conducted. NADH turnover frequencies are found to be dependent on the structure of the ligand and the results confirm

  15. Synthesis and cytotoxicity of dinuclear complexes containing ruthenium(II) bipyridyl units linked by a bis(pyridylimine) ligand.

    PubMed

    McDonnell, Ursula; Kerchoffs, Jessica M C A; Castineiras, Rosa P M; Hicks, Matthew R; Hotze, Anna C G; Hannon, Michael J; Rodger, Alison

    2008-02-07

    Enantiopure dinuclear ruthenium polypyridyl complexes of the form [Ru(2)(LL)(4)L(1)](PF(6))(4) (LL = 2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen); L(1)= C(25)H(20)N(4) a bis(pyridylimine) ligand containing a diphenylmethane spacer) have been synthesized using the chiral building blocks cis-[Ru(bpy)(2)(py)(2)](2+) and cis-[Ru(phen)(2)(py)(2)](2+). These dinuclear ruthenium complexes have been characterised using NMR, mass spectrometry, UV-visible absorbance, circular dichroism and linear dichroism. The compounds exhibit good photo and thermal stability. The extinction coefficient for the bpy complex at 478 nm is epsilon(478) = 15,700 mol(-1) cm(-1) dm(3) and for the phen complex is epsilon(478) = 24,900 mol(-1) cm(-1) dm(3). Both complexes have their longest wavelength (metal to ligand charge transfer) transition predominantly x/y (short axis)-polarised while the transitions at shorter wavelength are a mixture of x/y and z-polarisations, similar to both the copper helicate and iron triple helicate studied previously. Cytotoxicity studies reveal that the compounds are dramatically less active against cancer cell lines than the recently reported supramolecular cylinders prepared from the same bis(pyridylimine) ligand.

  16. Preparation of intercalation compounds of carbon fibers through electrolysis using phosphoric acid electrolyte and their exfoliation

    NASA Astrophysics Data System (ADS)

    Toyoda, Masahiro; Yoshinaga, Aya; Amao, Yutaka; Takagi, Hideyuki; Soneda, Yasushi; Inagaki, Michio

    2006-05-01

    Preparation of intercalation compounds using H3PO4 electrolyte solution in mesophase-pitch-based carbon fibers successfully carried out by electrolysis in less than 10 mol/dm3 of its electrolyte solution. Structural changes with preparation of intercalation compounds of carbon fibers were confirmed by a peak appeared around 2θ=8° observed after electrolysis, which corresponds to an interlayer spacing of about 0.9 nm through XRD pattern (anticathode: Cu Kα). This new peak was reasonably supposed to be due to the intercalation into interspacing of carbon layers. Suitable synthesis condition of the intercalation compounds was determined to be the concentration of electrolyte of 5 mol/dm3 at the electrolysis. It was also confirmed by morphology changes through SEM, that is carbon fibers, which treated low electrolyte concentration synthesized the intercalation compounds easily, and then it revealed markedly morphology changes such as fibrils. It could become exfoliation as well as them treated by other acid treatment through rapid heat-treatment. The formation of graphite oxide was suggested when the kind of intercalate was analyzed with elementary and TPD analysis.

  17. In situ monitoring of pH titration by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Elbagerma, M. A.; Azimi, Gholamhassan; Edwards, H. G. M.; Alajtal, A. I.; Scowen, I. J.

    2010-05-01

    Molecular speciation of organic compounds in solution is essential for the understanding of ionic complexation. The Raman technique was chosen because it allows the identification of compounds in different states, and it can give information about the molecular geometry from the analysis of the vibrational spectra. The effect of pH on organic compounds can give information about the ionisation of molecule species. In this study the ionisation steps of salicylic acid and paracetamol have been studied by means of potentiometry coupled with Raman spectroscopy at 30.0 °C in a solution of ionic strength 0.96 mol dm -3 (KNO 3) and 0.04 mol dm -3 (HNO 3). The protonation and deprotonation behaviour of the molecules were studied in different pH regions. The abundance of the three different species in the Raman spectra of aqueous salicylic acid have been identified satisfactorily, characterised, and determined by numeric treatment of the data using a multiwavelength curve-fitting program and confirmed with the observed spectral information.

  18. Comparative assessment of the methods for exchangeable acidity measuring

    NASA Astrophysics Data System (ADS)

    Vanchikova, E. V.; Shamrikova, E. V.; Bespyatykh, N. V.; Zaboeva, G. A.; Bobrova, Yu. I.; Kyz"yurova, E. V.; Grishchenko, N. V.

    2016-05-01

    A comparative assessment of the results of measuring the exchangeable acidity and its components by different methods was performed for the main mineral genetic horizons of texturally-differentiated gleyed and nongleyed soddy-podzolic and gley-podzolic soils of the Komi Republic. It was shown that the contents of all the components of exchangeable soil acidity determined by the Russian method (with potassium chloride solution as extractant, c(KCl) = 1 mol/dm3) were significantly higher than those obtained by the international method (with barium chloride solution as extractant, c(BaCl2) = 0.1 mol/dm3). The error of the estimate of the concentration of H+ ions extracted with barium chloride solution equaled 100%, and this allowed only qualitative description of this component of the soil acidity. In the case of the extraction with potassium chloride, the error of measurements was 50%. It was also shown that the use of potentiometric titration suggested by the Russian method overestimates the results of soil acidity measurement caused by the exchangeable metal ions (Al(III), Fe(III), and Mn(II)) in comparison with the atomic emission method.

  19. Preparation of zwitterionic hybrid polymer and its application for the removal of heavy metal ions from water.

    PubMed

    Liu, Junsheng; Ma, Yue; Xu, Tongwen; Shao, Guoquan

    2010-06-15

    A series of zwitterionic hybrid polymers were prepared from the ring-opening polymerization of pyromellitic acid dianhydride (PMDA) and phenylaminomethyl trimethoxysilane (PAMTMS), and a subsequent sol-gel process. FTIR spectra confirmed the step products. TGA analysis showed that the thermal degradation temperature increased with an increase in PMDA content. As a typical example, sample B was used to separate Cu(2+) and Pb(2+) removal by adsorption. It was indicated that its adsorption for Cu(2+) and Pb(2+) followed Lagergren second-order kinetic model and Langmuir isotherm model, demonstrating that the adsorption process might be Langmuir monolayer adsorption. Meanwhile, it was found that the adsorption capacity of Pb(2+) on sample B is beyond 12 times higher than that of Cu(2+) in 0.1 mol dm(-3) aqueous solution, revealing that it has larger affinity for Pb(2+). The desorption efficiency of Cu(2+) and Pb(2+) in 1 mol dm(-3) HNO(3) solution reached up to 96 and 89%, respectively; indicating that they can be regenerated and recycled in industry. These findings suggest that they are promising adsorbents for the selective removal of Pb(2+) from Pb(2+)/Cu(2+) mixed aqueous solution, and can be applied to separate and recover the heavy metal ions from contaminated water and waste chemicals.

  20. Enhancement of oxidative electrocatalytic properties of platinum nanoparticles by supporting onto mixed WO3/ZrO2 matrix

    NASA Astrophysics Data System (ADS)

    Rutkowska, Iwona A.; Wadas, Anna; Kulesza, Pawel J.

    2016-12-01

    Nanostructured mixed metal (W, Zr) oxide matrices (in a form of layered intercalated films of WO3 and ZrO2) are considered here for supporting and activating catalytic platinum nanoparticles toward electrooxidation of ethanol. Remarkable increases of electrocatalytic (voltammetric, chronoamperometric) currents measured in 0.5 mol dm-3 H2SO4 (containing 0.5 mol dm-3 ethanol) have been observed. Comparison has been made to the behavior of methanol and acetaldehyde under analogous conditions. The enhancement effects are interpreted in terms of specific interactions between platinum nanoparticles and the metal oxide species, high acidity of the mixed oxide sites, as well as high population of surface hydroxyl groups and high mobility of protons existing in close vicinity of Pt catalytic sites. The metal oxide nanostructures are expected to interact competitively (via the surface hydroxyl groups) with adsorbates of the undesirable reaction intermediates, including CO, facilitating their desorption ("third body effect"), or even oxidative removal (e.g., of CO to CO2). The fact that the partially reduced tungsten oxide (HxWO3) component is characterized by fast electron transfers coupled to proton displacements tends to improve the overall charge propagation at the electrocatalytic interface.

  1. Solvent extraction of silver picrate by 3m-crown-m ethers (m = 5, 6) and its mono-benzo-derivative from water into benzene or chloroform: elucidation of an extraction equilibrium using component equilibrium constants.

    PubMed

    Kudo, Yoshihiro; Usami, Jun; Katsuta, Shoichi; Takeda, Yasuyuki

    2004-03-10

    Ion-pair formation constant (K(AgPic) in mol(-1)dm(3)) of silver picrate (AgPic), those (K(AgLPic)) of its ion-pair complexes (AgLPic) with crown ethers (L) and complex formation constants (K(AgL)) of Ag(+) with L (15-crown-5 ether (15C5) and benzo-15C5) in water (w) were determined potentiometrically at 25 degrees C. Compounds used as L were 18-crown-6 ether (18C6), its benzo-derivative (B18C6) and the two 15C5 derivatives. Extraction constants (K(ex) in mol(-1)dm(3)) of AgPic with L (15C5, 18C6, B18C6) from acidic w-phases into either C(6)H(6) or CHCl(3) were recalculated from K(AgPic), K(AgL), K(AgLPic) and data opened in previous papers. Thus obtained K(ex) was divided into five component equilibrium constants containing K(AgL) and K(AgLPic) anew. Then, contributions of the component constants, K(AgL), K(AgLPic) and distribution constants of AgLPic between the w- and C(6)H(6)-phases, to K(ex) were discussed and compared with corresponding extraction systems of NaPic and KPic with18C6.

  2. The study of hydrogen bonding and π⋯π interactions in phenol⋯ethynylbenzene complex by IR spectroscopy.

    PubMed

    Vojta, Danijela; Vazdar, Mario

    2014-11-11

    Weak hydrogen bonds between phenol and ethynylbenzene in tetrachloroethene were explored by using FTIR spectroscopy. Association constants (Kc) were determined by high dilution method at two temperatures, 20°C and 26°C, and they are, respectively, 0.54±0.09 mol(-1) dm3 and 0.36±0.08 mol(-1) dm3. The position of ethynylbenzene stretching band, when in hydrogen bonding complex with phenol (CC⋯), is proposed to be governed by the interplay of OH⋯π (CC moiety or phenyl ring of ethynylbenzene) and π⋯π (phenyl ring of phenol⋯CC moiety or phenyl ring of ethynylbenzene) interactions. This conclusion is supported by the findings on the complex between ethanol and ethynylbenzene; in the latter, CC⋯ stretching band is shifted to the higher wavenumbers, as expected when ethynylbenzene interacts with hydrogen bond donor. Geometries and energies of the presumed complexes, as well as their vibrational spectra, are predicted by using ab initio calculations. The spectroscopic and thermodynamic data obtained here offer the missing pieces in the present picture of migration of H-atom of phenol OH group between competing hydrogen bond accepting centers on ethynylbenzene.

  3. Partial molar volumes and viscous properties of glycine-aqueous urea solutions at 298.15 K

    NASA Astrophysics Data System (ADS)

    Deosarkar, S. D.; Ban, A. R.; Tawde, P. D.; Sawale, R. T.

    2015-07-01

    Density (ρ) and viscosity (η) of glycine ( c = 0.02-0.22 mol dm-3) in aqueous urea ( c = 0.5, 1.5, and 3.0 mol dm-3) solutions were measured at 298.15 K. Experimental density data has been used to calculate apparent molar volumes (φv) of glycine in aqueous and aqueous-urea solutions at 298.15 K. The dependence of apparent molar volumes on concentration of glycine was fitted to the Massons relation and apparent molar volume of glycine at infinite dilution (partial molar volume, φ{v/0}) was determined graphically. The partial molar volumes of transfer (Δtrφ{v/0}) of glycine at infinite dilution from pure water to aqueous-urea solutions at 298.15 K were calculated and interpreted in terms of various interactions and structural fittings in studied solutions. The relative viscosity data has been analyzed by Jones-Dole relation and viscosity B-coefficients were determined graphically. Viscosity B-coefficient of transfer (Δ B) was also calculated and compared with Δtrφ{v/0}.

  4. Pulse radiolytic study of the oxidation reactions of uric acid in presence of bovine serum albumin. Evidence of possible complex formation in the transient state

    NASA Astrophysics Data System (ADS)

    Adhikari, S.; Joshi, R.; Gopinathan, C.

    1997-01-01

    The pulse radiolytic and spectrophotometric study of uric acid in presence of bovine serum albumin (BSA) has been carried out. In the spectrophotometric study there is no evidence for ground state interaction between BSA and uric acid. The oxidation reactions of uric acid in presence and absence of BSA employing CCl 3OO and Br radicals have been carried out. In a composition of equal concentration of uric acid and BSA, the CCl 3OO and Br radicals produce a transient absorption spectrum which show two peaks at 330 and 360 nm. The peak at 360 nm is ascribed due to weak complex formation between semioxidised BSA and uric acid radicals. The rate constant of CCl 3OO . radical with uric acid increases with the increase in BSA concentration which is explained as protection of BSA by uric acid from radical attack. The Br radical attacks uric acid and BSA in a manner similar to CCl 3OO radical. The bimolecular rate constants for the reaction of Br radical with BSA and uric acid have been found as 2.9 × 10 10 dm 3 mol -1 s -1 and 6.33 × 10 9 dm 3 mol -1 s -, respectively.

  5. Black carbon in cloud-water and rain water during monsoon season at a high altitude station in India

    NASA Astrophysics Data System (ADS)

    Budhavant, K. B.; Rao, P. S. P.; Safai, P. D.; Leck, C.; Rodhe, H.

    2016-03-01

    We present results of measurements of black carbon (BC) from ground-based wet-only rainwater (RW) and cloud-water (CW) sampling at a mountain field station, Sinhagad, situated in south western India during the period from June 2008 to October 2010. The amount of BC in the sample was determined by photometry at a wavelength of 528 nm after a procedure including the filtration through a 0.4 μm polycarbonate membrane filter. Water soluble concentrations of major anions in RW and CW were also determined. The average concentration of BC in RW (16 μmol dm-3) is higher by at least a factor 2 than that found in similar studies reported from other parts of the world. On the other hand, the average concentration of BC in CW (47 μmol dm-3) is lower by about a factor of 2 than that found at other sites. The ratio between the average concentrations in CW and RW varies from 2 (K+) to 7 (SO42-). The ratio for BC was about 3. No significant difference was observed for pH. Analysis of air mass back trajectories and of correlations between the various components indicates that long range transport of pollutants and dust from East Africa and Southern part of the Arabian peninsula might contribute to the high concentrations of BC and some of the ionic constituents at Sinhagad during the monsoon season.

  6. Influence of hydrogel structure on the processes of water penetration and drug release from mixed hydroxypropylmethyl cellulose/thermally pregelatinized waxy maize starch hydrophilic matrices.

    PubMed

    Michailova, V; Titeva, S; Kotsilkova, R; Krusteva, E; Minkov, E

    2001-07-03

    The kinetics of water penetration and molsidomine release from both hydroxypropylmethyl cellulose (HPMC) and mixed HPMC/thermally pregelatinized waxy maize starch (SDWMT) hydrophilic matrices has been examined in 0.1 mol x dm(-3) HCl (pH 1.0) and 0.06 mol x dm(-3) Na3PO4/HCl buffer (pH 6.8). The rheological oscillatory test parameters of their gel layers obtained by swelling of the matrices in the two aqueous media have been observed. The kinetic swelling properties of mixed HPMC/SDWMT hydrogels (i.e. degree and velocity of both water penetration and swelling, transport mechanism which controls solvent sorption) directly influence the drug release behaviour and the structural features of the formed gel layer. Both diffusion processes are diffusion-controlled ones, their mechanisms being influenced insignificantly by the relaxation properties of the hydrated macromolecules. It has been established by means of comparative viscoelastic analysis, that mixed HPMC/SDWMT hydrogels demonstrate the typical behaviour of 'filled' composite systems having poor adhesion between the surface of the elastic SDWMT 'filler' and the continuous HPMC phase. Due to the inter-phase relations between the swollen starch granules and the linear cellulose derivative as well as to the specific structure of amylopectin molecule, the pregelatinized waxy maize starch shows a stronger influence on the velocities of both water penetration and drug release from mixed HPMC/SDWMT matrices.

  7. Chemical repair activity of free radical scavenger edaravone: reduction reactions with dGMP hydroxyl radical adducts and suppression of base lesions and AP sites on irradiated plasmid DNA.

    PubMed

    Hata, Kuniki; Urushibara, Ayumi; Yamashita, Shinichi; Lin, Mingzhang; Muroya, Yusa; Shikazono, Naoya; Yokoya, Akinari; Fu, Haiying; Katsumura, Yosuke

    2015-01-01

    Reactions of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) with deoxyguanosine monophosphate (dGMP) hydroxyl radical adducts were investigated by pulse radiolysis technique. Edaravone was found to reduce the dGMP hydroxyl radical adducts through electron transfer reactions. The rate constants of the reactions were greater than 4 × 10(8) dm(3) mol(-1) s(-1) and similar to those of the reactions of ascorbic acid, which is a representative antioxidant. Yields of single-strand breaks, base lesions, and abasic sites produced in pUC18 plasmid DNA by gamma ray irradiation in the presence of low concentrations (10-1000 μmol dm(-3)) of edaravone were also quantified, and the chemical repair activity of edaravone was estimated by a method recently developed by the authors. By comparing suppression efficiencies to the induction of each DNA lesion, it was found that base lesions and abasic sites were suppressed by the chemical repair activity of edaravone, although the suppression of single-strand breaks was not very effective. This phenomenon was attributed to the chemical repair activity of edaravone toward base lesions and abasic sites. However, the chemical repair activity of edaravone for base lesions was lower than that of ascorbic acid.

  8. Electrocatalytic oxidation of ethanol in acid medium: Enhancement of activity of vulcan-supported Platinum-based nanoparticles upon immobilization within nanostructured zirconia matrices

    NASA Astrophysics Data System (ADS)

    Rutkowska, Iwona A.; Kulesza, Pawel J.

    2014-09-01

    Composite electrocatalytic materials that utilize carbon (Vulcan) supported Pt or PtRu nanoparticles dispersed within thin films of zirconia (ZrO2) are considered here for oxidation of such a biofuel as ethanol in acid medium. The systems were characterized using electrochemical techniques as well as transmission electron microscopy. The enhancement of activity was clearly evident upon comparison of the respective voltammetric and chronoamperometric current densities recorded (at room temperature in 0.5 mol dm-3H2SO4 containing 0.5 mol dm-3 ethanol) using the Vulcan supported Pt and PtRu catalysts in the presence and absence of zirconia. In all cases, the noble metal loading was the same, 100 μg cm-2. Apparently, the existence of large population of hydroxyl groups (originating from zirconia) in the vicinity of Pt-based catalyst, in addition to possible specific interactions between zirconia and the ruthenium component of PtRu, facilitated the oxidative removal (from Pt) of the passivating (e.g., CO) reaction intermediates (adsorbates). By utilizing carbon supported, rather than bare or unsupported, Pt or PtRu nanoparticles (dispersed within the semiconducting zirconia), the overall charge distribution at the electrocatalytic interface was improved.

  9. General observation of lithium intercalation into graphite in ethylene-carbonate-free superconcentrated electrolytes.

    PubMed

    Yamada, Yuki; Usui, Kenji; Chiang, Ching Hua; Kikuchi, Keisuke; Furukawa, Keizo; Yamada, Atsuo

    2014-07-23

    Lithium-ion batteries have exclusively employed an ethylene carbonate (EC)-based electrolyte to ensure the reversibility of the graphite negative electrode reaction. Because of the limitation of electrolyte compositions, there has been no remarkable progress in commercial lithium-ion batteries despite active research on positive electrode materials. Herein, we present a salt-superconcentrating strategy as a simple and effective method of universalizing a graphite negative electrode reaction in various organic solvents. A dilute electrolyte (e.g., 1 mol dm(-3)) of sulfoxide, ether, and sulfone results in solvent cointercalation and/or severe electrolyte decomposition at a graphite electrode, whereas their superconcentrated electrolyte (e.g., >3 mol dm(-3)) allows for highly reversible lithium intercalation into graphite. We have found a unique coordination structure in the superconcentrated solution and an anion-based inorganic SEI film on the cycled graphite electrode, which would be the origin of the reversible graphite negative electrode reaction without EC. Our salt-superconcentrating strategy, expanding the graphite negative electrode reaction in various organic solvents other than EC, will contribute to the development of advanced lithium-ion batteries with high-voltage and fast-charging characters based on new EC-free functional electrolytes.

  10. Preparation of Mg-vermiculite nanoparticles using potassium persulfate treatment.

    PubMed

    Matĕjka, Vlastimil; Supová-Krístková, Monika; Kratosvá, Gabriela; Valásková, Marta

    2006-08-01

    Delamination/exfoliation process of the Mg-vermiculite (Letovice, Czech Republic), particles with size less than 5 microm, was studied after potassium persulfate treatment and compared with known method utilized hydrogen peroxide treatment. X-ray powder diffraction (XRPD) patterns showed that treatment of Mg-vermiculite with different molar concentration of potassium persulfate: c = 0.02, 0.04, and 0.08 mol x dm(-3) at the temperature 60 degrees C for 2 hr caused reduction of relative intensity (I(rel.)) of the basal 001 diffraction to the 15%, 9%, and 4%, respectively, compared to intensity of 001 diffraction of untreated Mg-vermiculite (I(rel.) = 100%). On the other hand I(rel.) of the 001 diffraction of Mg-vermiculite after treatment with 30% and 50% (c = 9.8 and 17.4 mol x dm(-3)) hydrogen peroxide at the 60 degrees C for 2 hr decreased only to I(rel.) = 36% and 32%, respectively. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) verified effect of potassium persulfate treatment on structure degradation which is connected with higher degree of delamination/exfoliation of the particles and their cracking into nano-sized particles.

  11. Viscometric Studies in Dilute Solution Mixtures of Chitosan and Microcrystalline Chitosan with Poly(vinyl alcohol).

    PubMed

    Lewandowska, Katarzyna

    2013-01-01

    The viscosity behavior of aqueous mixtures formed by a polyelectrolyte (A) and a neutral polymer (B), such as chitosan/poly(vinyl alcohol) (Ch/PVA) and microcrystalline chitosan/poly(vinyl alcohol) (MCCh/PVA), have been investigated at 25 °C. The intrinsic viscosity and the viscosity interaction parameter of each polymer in 0.1 mol·dm(-3) CH3COOH/0.2 mol·dm(-3) NaCl solution as well as the ternary systems (polymer A/polymer B/solvent) have been determined and have served for estimation of the miscibility of different polymer mixtures by means of the method of classical dilution. By comparing the experimental and ideal viscosity data it is clearly seen that the satisfaction of the miscibility criterion depends on the definition of the ideal parameter [Formula: see text]. If the [Formula: see text] parameter is defined according to the Krigbaum-Wall criterion and Garcia criterion, the investigated blends of Ch/PVA satisfy the miscibility criterion. In the case of MCCh/PVA blends, the polymeric components show poor miscibility. Additionally, the viscosity results show that the degree of miscibility depends on the molecular weight of chitosan and on the degree of PVA hydrolysis.

  12. Catalytic behavior of a palladium doped binder free paper based cobalt electrode in electroreduction of hydrogen peroxide

    NASA Astrophysics Data System (ADS)

    Zhang, Dongming; Ye, Ke; Cao, Dianxue; Yin, Jinling; Cheng, Kui; Wang, Bin; Xu, Yang; Wang, Guiling

    2015-01-01

    A piece of flexible and conductive A4 paper is prepared by coating a layer of graphite with a normal 8B pencil. Then, Co nano-plates and Pd are assembled by a simple electrodeposition and chemical-reduction methods on the surface of the electrified paper, respectively. The as-prepared paper substrate/graphite-Co film-Pd (PG-CoPd) electrode is characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer, transmission electron microscope and X-ray diffractometer. The catalytic activity of the PG-CoPd electrode for H2O2 electroreduction is investigated by means of cyclic voltammetry and chronoamperometry. The preparation process of the PG-CoPd electrode does not use any binder and it exhibits a three dimensional (3D) nano structure, high stability and good electric conductivity. The mass of the Pd in PG-CoPd is about 0.0535 mg cm-2 and the reduction current density reaches to -4.30 A cm-2 mg-1 in 1 mol dm-3 NaOH and 1.4 mol dm-3 H2O2 at -0.5 V, which is higher than our previous reports of Au/Pd modified Co electrode.

  13. Speciation and structure of tin(II) in hyper-alkaline aqueous solution.

    PubMed

    Bajnóczi, Eva G; Czeglédi, Eszter; Kuzmann, Ernő; Homonnay, Zoltán; Bálint, Szabolcs; Dombi, György; Forgo, Péter; Berkesi, Ottó; Pálinkó, István; Peintler, Gábor; Sipos, Pál; Persson, Ingmar

    2014-12-28

    The identity of the predominating tin(ii)-hydroxide complex formed in hyper-alkaline aqueous solutions (0.2 ≤CNaOH≤ 12 mol dm(-3)) is determined by potentiometric titrations, Raman, Mössbauer and XANES spectroscopy, supplemented by quantum chemical calculations. Thermodynamic studies using a H2/Pt electrode up to free hydroxide concentrations of 1 mol dm(-3) showed the presence of a single monomeric complex with a tin(II) : hydroxide ratio of 1 : 3. This observation together with Raman and Mössbauer spectroscopic measurements supplemented by quantum mechanical calculations proved that the predominating complex is [Sn(OH)3](-), and that the presence of the other possible complex, [SnO(OH)](-), could not be proven with either experiments or simulations. The structure of the trihydroxidostannate(II) complex, [Sn(OH)3](-), was determined by EXAFS and was found to be independent of the applied hydroxide and tin(II) concentrations. The mean Sn-O bond distance is short, 2.078 Å, and in very good agreement with the only structure reported in the solid state. It is also shown that at pH values above 13 the speciation of the predominant trihydroxidostannate(II) complex is not affected by the presence of high concentrations of chloride ions.

  14. The exploration of hydrogen bonding properties of 2,6- and 3,5-diethynylpyridine by IR spectroscopy

    NASA Astrophysics Data System (ADS)

    Vojta, Danijela; Kovačević, Goran; Vazdar, Mario

    2015-02-01

    Hydrogen bonding properties of 2,6- and 3,5-diethynylpyridine were analyzed by exploring of their interactions with trimethylphosphate, as hydrogen bond acceptor, or phenol, as hydrogen bond donor, in tetrachloroethene C2Cl4. The employment of IR spectroscopy enabled unravelling of their interaction pattern as well as the determination of their association constants (Kc) and standard reaction enthalpies (ΔrH⦵). The association of diethynylpyridines with trimethylphosphate in stoichiometry 1:1 is established through tbnd Csbnd H⋯O hydrogen bond, accompanied by the secondary interaction between Ctbnd C moiety and CH3 group of trimethylphosphate. In the complexes with phenol, along with the expected OH⋯N interaction, Ctbnd C⋯HO interaction is revealed. In contrast to 2,6-diethynylpyridine where the spatial arrangement of hydrogen bond accepting groups enables the simultaneous involvement of phenol OH group in both OH⋯N and OH⋯Ctbnd C hydrogen bond, in the complex between phenol and 3,5-diethynylpyridine this is not possible. It is postulated that cooperativity effects, arisen from the certain type of resonance-assisted hydrogen bonds, contribute the stability gain of the latter. Associations of diethynylpyridines with trimethylphosphate are characterized as weak (Kc ≈ 0.8-0.9 mol-1 dm3; -ΔrH⦵ ≈ 5-8 kJ mol-1), while their complexes with phenol as medium strong (Kc ≈ 5 mol-1 dm3; -ΔrH⦵ ≈ 15-35 kJ mol-1). Experimental findings on the studied complexes are supported with the calculations conducted at B3LYP/6-311++G(d,p) level of theory in the gas phase. Two conformers of diethynylpyridine⋯trimethylphosphate dimers are formed via tbnd Csbnd H⋯O interaction, whereas dimers between phenol and diethynylpyridines are established through OH⋯N interaction.

  15. Kinetics and thermodynamics of copper ions removal from wastewater by use of zeolite.

    PubMed

    Panayotova, M I

    2001-01-01

    Natural Bulgarian zeolite was tested for its ability to remove Cu2+ from model wastewater. Influence of process variables was investigated. It was found that the optimum wastewater to zeolite ratio is 100:1 and the optimum pH value of water to be treated is 5.5 to 7.5. Zeolite with finer particles shows a higher uptake capacity. The simultaneous presence of Ca2+ and Mg2+ in concentrations similar to their concentrations in Bulgarian natural water does not significantly influence the uptake of Cu2+. Zeolite modification by treating it with NaCl, CH3COONa and NaOH increases its uptake ability. Copper ions are strongly immobilized by modified zeolite and secondary pollution of water caused by its contact with preloaded zeolite is very low (1.5-2.5% of Cu2+ preliminary immobilized have been released back into acidified water). Contacting with 2 mol dm(-3) NaCl can easily regenerate loaded zeolite; best results were obtained for zeolite modified with NaCl. Requirements of Bulgarian standards for industrial wastewater can be met by a one-stage process for an initial Cu2+ concentration of 10 mg dm(-3), and by a two stage process for an initial Cu2+ concentration of 50 mg dm(-3). Uptake of Cu2+ by zeolite from neutral wastewater has proved to be as effective as Cu2+ removal by precipitation of copper hydroxide. The process of Cu2+ uptake by natural zeolite is best described by the kinetic equation for adsorption. This fact, together with the correlation found between the Cu2+ uptake and the amount of Na+, Ca2+ and K+ released into solution by zeolite shows that the ion exchange sorption plays the basic role in Cu2+ uptake by natural zeolite. The value obtained for the apparent activation energy (26.112 kJ mol(-1) implies that the process can be easily carried out with a satisfactory rate. The uptake equilibrium is best described by the Langmuir adsorption isotherm, with Langmuir constants KL= 6.4 x 10(-2) dm3 mg(-1) and M = 6.74 mg g(-1). The apparent equilibrium constant

  16. Kinetics of N-nitrosopiperazine formation from nitrite and piperazine in CO2 capture.

    PubMed

    Goldman, Mark J; Fine, Nathan A; Rochelle, Gary T

    2013-04-02

    Piperazine (PZ) is an efficient amine for carbon capture systems, but it can form N-nitrosopiperazine (MNPZ), a carcinogen, from nitrogen oxides (NO(x)) in flue gas from coal or natural gas combustion. The reaction of nitrite with PZ was studied in 0.1 to 5 mol/dm(3) PZ with 0.001 to 0.8 mol CO2/mol PZ at 50 to 135 °C. The reaction forming MNPZ is first order in nitrite, piperazine carbamate species, and hydronium ion. The activation energy is 84 ± 2 kJ/mol with a rate constant of 8.5 × 10(3) ± 1.4 × 10(3) dm(6) mol(-2) s(-1) at 100 °C. The proposed mechanism involves protonation of the carbamate species, nucleophilic attack of the carbamic acid, and formation of bicarbonate and MNPZ. These kinetics and mechanism will be useful in identifying inhibitors and other strategies to reduce nitrosamine accumulation in CO2 capture by scrubbing with PZ or other amines.

  17. Inhibition of MAO and COMT by hypericum extracts and hypericin.

    PubMed

    Thiede, H M; Walper, A

    1994-10-01

    The influence of hypericin, hypericum total extract, and hypericum fractions on the activity of MAO and COMT, prepared in vitro from pork liver, were investigated in several concentration steps. An inhibition of MAO could be shown in the following concentrations (extract correlated to a mean molecular value of 500): hypericin to 10(-3) mol/L, hypericum total extract to 10(-4) mol/L, one extract fraction up to 10(-5). A COMT inhibition could not be shown for hypericin, with hypericum extract to 10(-4) mol/L and with two extract fractions also up to 10(-4) mol/L. The MAO inhibiting fraction contained hypericins as well as flavonols, the COMT-inhibition fraction being mainly flavonols and xanthones. The concentrations of inhibition shown might not be sufficient to explain the clinically proven antidepressive effect of hypericum particularly with regard to the inhibition of MAO activity.

  18. Simultaneous square-wave voltammetric determination of aspartame and cyclamate using a boron-doped diamond electrode.

    PubMed

    Medeiros, Roberta Antigo; de Carvalho, Adriana Evaristo; Rocha-Filho, Romeu C; Fatibello-Filho, Orlando

    2008-07-30

    A simple and highly selective electrochemical method was developed for the simultaneous determination of aspartame and cyclamate in dietary products at a boron-doped diamond (BDD) electrode. In square-wave voltammetric (SWV) measurements, the BDD electrode was able to separate the oxidation peak potentials of aspartame and cyclamate present in binary mixtures by about 400 mV. The detection limit for aspartame in the presence of 3.0x10(-4) mol L(-1) cyclamate was 4.7x10(-7) mol L(-1), and the detection limit for cyclamate in the presence of 1.0x10(-4) mol L(-1) aspartame was 4.2x10(-6) mol L(-1). When simultaneously changing the concentration of both aspartame and cyclamate in a 0.5 mol L(-1) sulfuric acid solution, the corresponding detection limits were 3.5x10(-7) and 4.5x10(-6) mol L(-1), respectively. The relative standard deviation (R.S.D.) obtained was 1.3% for the 1.0x10(-4) mol L(-1) aspartame solution (n=5) and 1.1% for the 3.0x10(-3) mol L(-1) cyclamate solution. The proposed method was successfully applied in the determination of aspartame in several dietary products with results similar to those obtained using an HPLC method at 95% confidence level.

  19. Characterization of relaxant mechanism of H2 S in mouse corpus cavernosum.

    PubMed

    Aydinoglu, Fatma; Ogulener, Nuran

    2016-04-01

    The aim of this study was to investigate the mechanism of H2 S-induced relaxation in mouse corpus cavernosal tissue. l-cysteine (10(-6) × 10(-3) mol/L) and exogenous H2 S (NaHS; 10(-6) to 10(-3) mol/L) induced concentration-dependent relaxation. l-cysteine-induced relaxations was reduced by d,l-propargylglycine, a cystathionine gamma lyase (CSE) inhibitor but not influenced by aminooxyacetic acid, a cystathionine beta synthase (CBS) inhibitor. l-cysteine induced relaxations, but not of those of H2 S diminished in endothelium-denuded tissues. N(ω) -nitro-l-arginine (l-NA; 10(-4) mol/L), a nitric oxide synthase inhibitor, and ODQ (10(-4) mol/L), a guanylyl cyclase inhibitor, increased the H2 S-induced relaxation. Zaprinast (5 × 10(-6) mol/L) and sildenafil (10(-6) mol/L), phosphodiesterase inhibitors, inhibited H2 S-induced relaxation. Adenylyl cyclase inhibitors N-ethylmaleimide (2.5 × 10(-5) mol/L) and SQ22536 (10(-4) mol/L) reduced relaxation to H2 S. Also, H2 S-induced relaxation was reduced by KCl (50 mmol/L), 4-aminopyridine (10(-3) mol/L), a Kv inhibitor, glibenclamide (10(-5) mol/L), a KATP inhibitor or barium chloride (10(-5) mol/L), a KIR inhibitor. However, H2 S-induced relaxation was not influenced by apamin (10(-6) mol/L), a SKC a (2+) inhibitor, charybdotoxin (10(-7) mol/L), an IKC a (2+) and BKC a (2+) inhibitor or combination of apamin and charybdotoxin. Nifedipine (10(-6) mol/L), an L-type calcium channel blocker and atropine (10(-6) mol/L), a muscarinic receptor blocker, inhibited H2 S-induced relaxation. However, H2 S-induced relaxation was not influenced by ouabain (10(-4) mol/L), a Na(+) /K(+) -ATPase inhibitor. This study suggests that H2 S endogenously synthesizes from l-cysteine by CSE endothelium-dependent in mouse corpus cavernosum tissue, and exogenous H2 S may cause endothelium-independent relaxations via activation of K channels (KATP channel, KV channels, KIR channels), L-type voltage-gated Ca(2+) channels, adenylyl cyclase

  20. Computer modelling of the chemical speciation of caesium, uranium(VI) and neptunium(V) in human duodenal fluids under fasting conditions.

    PubMed

    Jones, Paul W; Taylor, David M; Webb, Louise M; Williams, David R

    2002-08-01

    A model simulating the human duodenal contents under physiologically realistic, fasting conditions was developed using the joint expert speciation system (JESS) computer program and database and used to investigate the chemical speciation of caesium, uranium(VI) and neptunium(V). Over the pH range 5.0-9.0, and the concentration range 5 x 10(-15) x 10(-5) mol dm(-3), caesium was predicted to occur predominantly as the absorbable free monovalent cation Cs+ (approximately 95%) with species such as CsHPO4- and CsCl representing the remainder. The presence or absence of sulphate at 2.1 x 10(-3) mol dm(-3) did not influence the predicted speciation. Uranium was predicted to be present entirely as a soluble, highly charged species, both in the absence and in the presence of sulphate. Between pH 5.0 and approximately 6.5 the UO2H2(PO4)2(2-) predominated, above this pH carbonate species, either UO2(CO3)4(6-) or, possibly, UO2(CO3)5(8-). At pH 8.0, and in the presence of sulphate, neptunium(V) was predicted to exist solely as the tetrasulphate species, whilst in the absence of sulphate, an array of negatively charged soluble carbonate species predominated. Studies over the pH range 5.0-9.0 predicted the formation of a spectrum of negatively charged carbonate and phosphate species, approximately 40% of the total neptunium was predicted to be present as the electrically net-neutral species NpO2HCO3 at pH6.0, approximately 20% at pH 7.0, approximately 10% at pH 7.5 and approximately 1% at pH 8.0. The observed speciation patterns of uranium and neptunium did not change over the concentration range 5 x 10(-15) - 5 x 10(-5) mol dm(-3) and no solid species were predicted to occur under the conditions simulated. Whether the predicted electrically net-neutral neptunium species or the uranium pentacarbonate species do actually occur under true physiological conditions remains to be established. The observed speciation patterns for caesium and uranium are consistent with the observed

  1. Specific chiral sensing of amino acids using induced circularly polarized luminescence of bis(diimine)dicarboxylic acid europium(III) complexes.

    PubMed

    Okutani, Kazuhiro; Nozaki, Koichi; Iwamura, Munetaka

    2014-06-02

    The circularly polarized luminescence (CPL) from [Eu(pda)2](-) (pda = 1,10-phenanthroline-2,9-dicarboxylic acid) and [Eu(bda)2](-) (bda = 2,2'-bipyridine-6,6'-dicarboxylic acid) in aqueous solutions containing various amino acids was investigated. The europium(III) complexes exhibited bright-red luminescence assignable to the f-f transition of the Eu(III) ion when irradiated with UV light. Although the luminescence was not circularly polarized in the solid state or in aqueous solutions, in accordance with the achiral crystal structure, the complexes exhibited detectable induced CPL (iCPL) in aqueous solutions containing chiral amino acids. In the presence of L-pyrrolidonecarboxylic acid, both [Eu(pda)2](-) and [Eu(bda)2](-) showed similar iCPL intensity (glum ∼ 0.03 for the (5)D0 → (7)F1 transition at 1 mol·dm(-3) of the amino acid). On the other hand, in the presence of L-histidine or L-arginine, [Eu(pda)2](-) exhibited intense CPL (glum ∼ 0.08 for the (5)D0 → (7)F1 transition at 0.10 mol·dm(-3) of the amino acid), whereas quite weak CPL was observed for [Eu(bda)2](-) under the same conditions (glum < 0.01). On the basis of analysis of the iCPL intensities in the presence of 12 amino acids, [Eu(pda)2](-) was found to be a good chiral CPL probe with high sensitivity (about 10(-2) mol·dm(-3)) and high selectivity for L-histidine at pH 3 and for L-arginine at pH 7. The mechanism of iCPL was evaluated by analysis of the fine structures in the luminescence spectra and the amino acid concentration dependence of glum. For the [Eu(pda)2](-)-histidine/arginine systems, the europium(III) complexes possess coordination structures similar to that in the crystal with slight distortion to form a chiral structure due to specific interaction with two zwitterionic amino acids. This mechanism was in stark contrast to that of the europium(III) complex-pyrrolidonecarboxylic acid system in which one amino acid coordinates to the Eu(III) ion to yield an achiral coordination

  2. Commentary on "The Evolutionary Origin of Female Orgasm" by M. Pavlicev and G. Wagner, 2016, J. Exp. Zool. (Mol. Dev. Evol.) 326(6):326-337.

    PubMed

    Komisaruk, Barry R

    2016-12-01

    Evidence is presented as an alternative to the authors' claims that in the course of evolution, a link between orgasm and ovulation has been lost in women, that evolutionary changes in clitoral anatomy underlie this loss, and that women's orgasm plays no significant role in reproduction.

  3. The production of W-0.35HfC (Mol %) wirebar by arc melting and high energy rate extrusion of small diameter ingots

    NASA Astrophysics Data System (ADS)

    Buckman, R. William; Begg, Lester L.

    1991-01-01

    Tungsten alloy fiber reinforced tungsten is a candidate emitter material for space nuclear thermionic multi-kilowatt power systems. Fuel swelling which results in emitter deformation has been a primary concern for being able to achieve long lived (7 years or greater) thermionic fuel elements (TFE) operating at temperatures at or above 1900 K. The tungsten alloy (W-0.35 mo/%HfC) has extremely attractive mechanical properties above 1900 K and is a candidate reinforcement of tungsten for emitters. Because of its high strength, processing of the W-035HfC alloy to small diameter (0.38mm) wire has been difficult and the yield of useable product has been low. The purpose of this work was to demonstrate that by vacuum arc melting 38mm diameter ingots and high energy rate extrusions, small diameter (18mm) rod could be produced which is more compatible with swaging equipment used in tungsten wire production. Six 38 mm diameter ingots of W-0.35 HfC were produced by consumable electrode vacuum arc melting. The ingots were clad in 46 mm diameter molybdenum heated to 2270K and successfully extruded through a zirconia coated die at a reduction ratio of 7:1. The microstructure of the as-extruded bars is highly worked and should be amenable to processing to small diameter wire.

  4. The production of W-0. 35HfC (Mol %) wirebar by arc melting and high energy rate extrusion of small diameter ingots

    SciTech Connect

    Buckman, R.W. Jr. ); Begg, L.L. )

    1991-01-01

    Tungsten alloy fiber reinforced tungsten is a candidate emitter material for space nuclear thermionic multi-kilowatt power systems. Fuel swelling which results in emitter deformation has been a primary concern for being able to achieve long lived (7 years or greater) thermionic fuel elements (TFE) operating at temperatures at or above 1900 K. The tungsten alloy (W-0.35 mo/%HfC) has extremely attractive mechanical properties above 1900 K and is a candidate reinforcement of tungsten for emitters. Because of its high strength, processing of the W-035HfC alloy to small diameter (0.38mm) wire has been difficult and the yield of useable product has been low. The purpose of this work was to demonstrate that by vacuum arc melting 38mm diameter ingots and high energy rate extrusions, small diameter (18mm) rod could be produced which is more compatible with swaging equipment used in tungsten wire production. Six 38 mm diameter ingots of W-0.35 HfC were produced by consumable electrode vacuum arc melting. The ingots were clad in 46 mm diameter molybdenum heated to 2270K and successfully extruded through a zirconia coated die at a reduction ratio of 7:1. The microstructure of the as-extruded bars is highly worked and should be amenable to processing to small diameter wire.

  5. Ouverture mécanique de la molécule d'ADN par micro-manipulation et mesure de force

    NASA Astrophysics Data System (ADS)

    Bockelmann, Ulrich; Essevaz-Roulet, B.; Thomen, Philippe; Heslot, François

    In this paper we summarize part of our work on the mechanical unzipping of DNA. We have prepared molecular constructions which allow us to attach the two complementary strands of one end of a single DNA molecule of the bacteriophage λ separately to a glass microscope slide and a microscopic bead. In a first series of experiments, a soft microneedle acting as a force sensor is attached to the bead and its deflection is measured with an optical microscope. In a second series, we use an optical trapping interferometer to capture the bead and to measure its displacement to nm resolution. The sample is slowly displaced with respect to the force measurement device, leading to a progressive opening of the double helix. The force measured during this mechanical opening shows a characteristic variation which is related to the base pair sequence of the DNA molecule. To cite this article: U. Bockelmann et al., C. R. Physique 3 (2002) 585-594.

  6. [Development of a cookie formulation for celiac people using defatted Chilean hazel nut (Gevuina avellana. Mol) flour and quinoa (Chenopodium quinoa Willd) flour].

    PubMed

    Villarroel, Mario; Huiriqueo, Carolina; Hazbun, Julia; Carrillo, Diego

    2009-06-01

    The present investigation deals with the optimization of a cookie formulation based on deffated chilean hazel nut flour (DCHF) and quinoa flour (QF) characterized for being gluten free resources, aimed to increment the nutritional options of the celiac population using Taguchi methodology. Four independent variables DCHF, QF, ammonium bicarbonated (AB) and baking time (BT) at three levels each one were considered in orden to evaluate their effects on the sensory quality (SQ) and signal to noise ratio (S/N) of the optimized product. To determine the optimun levels and relative magnitude of the effects of each parameter L9 3(4) orthogonal array with nine design points and two replications each totalizing eighteen experimental runs was used. Results were analyzed using differences between the average values of each factor according to the working level and also analysis of variance (ANOVA). The desired characteristics were the maxima SQ and S/R responses, so Taguchi "the larger the better" performance formula was used. Optimun conditions turn out to be DCHF 24.3%; QF 7.1%; AB 0.6%; BT 22 minutes. Among the chemical characteristics highlighted components such as protein (8.9%) and fiber (12.7%). Regarding the prolamine content of 1.5 ppm its result was under the limit considered for CODEX (20 ppm) classifying this product as gluten free. On the other hand, the shelf life study expressed as conjugated dienes (CD) was 3.6% after 45 days at 30 degrees C storage conditions proving this product is stable to rancidness. Hedonic test data shown 100% approval, splitted as follow 75% (like very much) and 25% (like). Finally 100% of celiac peoples inquired in this study were well disposed to buy this product.

  7. Étude de la transition entre le gaz atomique et le gaz moléculaire dans deux cirrus de la boucle céleste nord

    NASA Astrophysics Data System (ADS)

    Barriault, Léo

    2010-11-01

    The infrared (IR) cirrus clouds observed at high Galactic latitude are excellent candidates to study the transition between the atomic gas and the molecular gas. In this thesis, two potential sites of H2 formation have been discovered in the North Celestial Loop (l = 135°, b = 40°) through examining the far-IR-Hl ratio and looking for an excess over that expected from an atomic medium. I call these sites the Spider and Ursa Major fields. The comparison between the IR excess map and the 12CO (J - 1 - 0) data from the Five College Radio Astronomical Observatory (resolution = 45 arcsec) shows that the IR excess peaks do not coincide with the 12CO peaks. The absence of coincidence is explained by (i) a density too small to allow CO excitation, (ii) insufficient CO self-shielding or (iii) variations of the dust properties. The comparison between 12CO data and Hi data from the Dominion Radio Astrophysical Observatory (resolution = 1 arcmin) is in agreement with the models! that predict CO formation where large velocity shears and turbulence dissipation are observed. OH observations of 108 locations over the two diffuse clouds from the Green Bank Telescope (resolution = 7 arcmin) are analyzed. OH is a precursor molecule to CO and its formation requires H2. The coincidence between the OH emission peak and the IR excess peak indicates that OH could be a better tracer of H2 than CO in these low-density regions. 12CO (7 = 1-0) and 13CO (J = 1 -0) observations from the Institut de Radioastronomie Millimétrique and 12CO ( J = 2 - 1) observations from the James Clerk Maxwell Telescope (resolution = 20 arcsec) are analyzed on a small number of fields in both regions. Using a large velocity gradient model, we found smaller densities at the location of the IR excess peak while self-shielding should be efficient given the computed column densities.

  8. Structural and Dielectric Investigation on the Nature of the Transition in a Copolymer of Vinylidene Fluoride and Trifluoroethylene (52/48 Mol %).

    DTIC Science & Technology

    1981-11-01

    preceding study 8 , and had been kindly supplied by 9 Daikin Kogyo Co., Ltd., Japan ; an experimental sample of poly- 9 trifluoroethylene was kindly...gradual lattice changes to the final helical structure. ACKNOWLEDGEUMENTS Thanks are due to Drs. J. Sako of Daikin Kogyo Co., Ltd., and R. Ferren of

  9. The hydrolysis and precipitation of Pd(II) in 0.6 mol kg-1 NaCl: A potentiometric, spectrophotometric, and EXAFS study

    SciTech Connect

    Boily, Jean F.; Seward, Terry M.; Charnock, John M.

    2007-10-15

    The hydrolysis of palladium was investigated in 0.6 mol•kg-1 NaCl at 298.2 K. Potentiometric titrations of solutions at various total concentrations of palladium(II) revealed that dilute (millimolar) conditions can be used to monitor the proton release due to hydrolysis reactions up to 2 protons per palladium(II) as long as the equilibration time is kept small. Spectrophotometric titrations were used to corroborate the homogeneous changes in speciation for the PdCl3OH2- species and to extract its correlative molar absorption coefficients in the 210-320 nm range. The molar absorption coefficients are similar to those of PdCl42- but exhibit a broader distribution of excitation energies resulting from the blue shift of the dominant charge transfer bands due to the presence of OH-. The longer-term potentiometric titrations systematically yielded, on the other hand, precipitates which matured over a period of 6 weeks and resulted in a more extensive release of protons to the solution. Precipitation experiments at six different total palladium(II) concentrations in the 3-11 pH range showed the dominant precipitating phase as Pd(OH)1.72Cl0.28. The coordination environment of Pd in this solid was investigated by extended X-ray absorption fine structure spectroscopy (EXAFS) and yielded an average 1.75 O and 0.25 Cl per Pd atoms with a Pd-O distance of 2.0 Å and Pd-Cl of 2.1 Å. Finally, the precipitation experiments showed the final products to be of larger solubility than a literature Pd(OH)2 solubility study in which the KCl media induced a solid phase transformation to Pd(OH)1.72Cl0.28. Polynuclear complexes Pdq(OH)r2q-r with q=r=[3,9] explain the combined precipitation and hydrolysis data and may represent subsets of [Pd(OH)2]n and/or [Pd(OH)1.72Cl0.28]n chains coiled into nanometer-sized spheroids previously described in the literature.

  10. The Multiple Forms of α-Amylase Enzyme of the Araucaria Species of South America: A. araucana (Mol.) Koch and A. angustifolia (Bert.) O. Kutz 1

    PubMed Central

    Salas, Elizabeth; Cardemil, Liliana

    1986-01-01

    α-Amylase is one of the major enzymes present in the seeds of both Araucaria species of South America and it initiates starch hydrolysis during germination and early seedling growth. The pattern of the multiple forms of α-amylase of the two Araucaria species was investigated by electrophoresis and isoelectrofocusing of the native enzyme in polyacrylamide gels. The enzyme forms were compared in the embryo and megagametophyte of quiescent seeds and of seeds imbibed for 18, 48, and 90 hours. Specific α-amylase enzyme forms appear and disappear during these imbibition periods showing both similarities and differences between tissues and species. Before imbibition, there are five α-amylase forms identical in both tissues, but different between species. After 18 hours of imbibition, there are two enzyme forms in both tissues of Araucaria araucana seeds, only one form in the embryo of Araucaria angustifolia but two forms in the megagametophyte of this specie. After 48 hours of seed imbibition, most of the enzyme forms present in quiescent seeds reappear. At 90 hours of imbibition different enzyme forms are detected in the embryo with respect to the gametophyte. The changes in form patterns of α-amylase are discussed according to a possible regulation of gene expression by endogenous gibberellins. Images Fig. 1 Fig. 2 Fig. 3 PMID:16664944

  11. Corrigendum to "Electronic structure and photoelectron spectra of nickel (II) acetylacetonate and its thio- and amino-substituted analogues" [J. Mol. Struct. 1099 (2015) 579-587

    NASA Astrophysics Data System (ADS)

    Vovna, Vitaliy I.; Korochentsev, Vladimir V.; Komissarov, Alexander A.; L'vov, Igor B.; Myshakina, Nataliya S.

    2016-01-01

    The authors regret to inform that it was given erroneous spelling of Vitaliy I. Vovna author name in the published version of the article. It was written "Vitaliy V. Vovna" instead of "Vitaliy I. Vovna".

  12. Crystal and mol­ecular structures of two silver(I) amidinates, including an unexpected co-crystal with a lithium amidinate

    PubMed Central

    Wang, Sida; Harmgarth, Nicole; Liebing, Phil; Edelmann, Frank T.

    2016-01-01

    The silver(I) amidinates bis­[μ-N 1,N 2-bis­(propan-2-yl)benzamidinato-κ2 N 1:N 2]disilver(I), [Ag2(C13H19N2)2] or [Ag{PhC(NiPr)2}]2 (1), and bis­(μ-N 1,N 2-di­cyclohexyl-3-cyclo­propyl­propynamidinato-κ2 N 1:N 2)disilver(I), [Ag2(C18H27N2)2] or [Ag{cyclo-C3H5–C≡C–C(NCy)2}]2 (2a), exist as centrosymmetric dimers with a planar Ag2N4C2 ring and a common linear coordination of the metal atoms in the crystalline state. Moiety 2a forms a co-crystal with the related lithium amidinate, namely bis­(μ-N 1,N 2-di­cyclo­hexyl-3-cyclo­propyl­propynamidinato-κ2 N 1:N 2)disilver(I) bis­(μ-N 1,N 2-di­cyclo­hexyl-3-cyclo­propyl­propynamidinato-κ3 N 1,N 2:N 1)bis­(tetra­hydro­furan-κO)lithium(I) toluene monosolvate, [Ag2(C18H27N2)2][Li2(C18H27N2)2(C4H8O)2]·C7H8 or [Ag{cyclo-C3H5–C≡C–C(NCy)2}]2[Li{cyclo-C3H5–C≡C–C(NCy)2}(THF)]2·C7H8, composed as 2a × 2b × toluene. The lithium moiety 2b features a typical ladder-type dimeric structure with a distorted tetra­hedral coordination of the metal atoms. In the silver(I) derivatives 1 and 2a, the amidinate ligand adopts a μ-κN:κN′ coordination, while it is a μ-κN:κN:κN′-coordination in the case of lithium derivative 2b. PMID:27980831

  13. Corrigendum to "Synthesis, crystal structure and electrochemical and DNA binding studies of oxygen bridged-copper(II) carboxylate" [J. Mol. Struct. 1093 (2015) 135-143

    NASA Astrophysics Data System (ADS)

    Iqbal, Muhammad; Ali, Saqib; Tahir, Muhammad Nawaz; Muhammad, Niaz; Shah, Naseer Ali; Sohail, Manzar; Pandarinathan, Vedapriya

    2017-04-01

    The authors regret to inform that Scheme 1 in the article titled 'Synthesis, crystal structure and electrochemical and DNA binding studies of oxygen bridged-copper(II) carboxylate' in vol. 1093 of the Journal of Molecular Structure is incorrect. The corrected scheme is as shown in this correction. This is purely a copy error. The error does not affect the conclusion in paper. The authors would like to apologize for any inconvenience caused.

  14. H+ClCN→HCl+CN: Product excitations and reaction mechanism at Ec.m. ≂21.6 kcal mol-1

    NASA Astrophysics Data System (ADS)

    de Juan, J.; Callister, S.; Reisler, H.; Segal, G. A.; Wittig, C.

    1988-08-01

    Nascent CN(X 2Σ) rovibrational and kinetic energy distributions have been obtained for the title reaction using laser induced fluorescence, and regions of the HClCN potential energy surface appropriate to the observed HCl+CN channel, as well as the HCN+Cl and HNC+Cl channels, have been calculated ab initio at the MP4/3-21G* level. The CN spectator has low internal excitation; the average fractions of the available energy deposited in CN vibration and rotation are < fV(CN)> ˜0 and < fR(CN)> =0.06, respectively, with the rotational distribution corresponding to a temperature of ˜950 K. Sub-Doppler resolution spectroscopy on several CN B 2Σ←X 2Σ transitions provides an average value for the fraction of the available energy appearing as center-of-mass kinetic energy, < fT> =0.33, as well as approximate kinetic energy distributions for specific CN V,R levels. Since the kinetic energy distributions are for specific CN levels, the corresponding HCl internal energy distributions are obtained by energy conservation, and the experimental results indicate a vibrational population inversion in HCl. Product energy disposal is similar to that of many ``light+heavy-heavy'' systems which exhibit repulsive energy release and which prefer end-on rather than broadside entrance channels. The dominant reaction pathways are probably HCN+Cl and HNC+Cl, with HCl+CN being minor. Because of the competitiveness between the chemically distinct product channels, the entrance channel associated with the observed products is more stereospecifically constrained than for a similar reaction which has a single set of products. The ab initio calculations suggest that end-on encounters can be reactive, thus accounting for the observed channel. A local minimum exists for a three-center structure involving hydrogen, chlorine, and carbon, and the barrier from here to HCN+Cl is small. Broadside approaches give rise to HCN+Cl, and we therefore surmise that the observed products derive predominantly from encounters in which the H atom approaches the chlorine over a modest range of angles and impact parameters. Linear approaches at the nitrogen end of the molecule are unreactive at the energies of the present experiments. However, there is a cis transition state leading to HNC+Cl which is low enough to participate in the overall chemistry. Thus, the ab initio calculations are consistent with the experimental observations, and suggest that the title reaction is a minor channel, and that CN+HCl is produced by direct reaction via attack at the chlorine.

  15. ExoMol molecular line lists XIX: high-accuracy computed hot line lists for H218O and H217O

    NASA Astrophysics Data System (ADS)

    Polyansky, Oleg L.; Kyuberis, Aleksandra A.; Lodi, Lorenzo; Tennyson, Jonathan; Yurchenko, Sergei N.; Ovsyannikov, Roman I.; Zobov, Nikolai F.

    2017-04-01

    Hot line lists for two isotopologues of water, H218O and H217O, are presented. The calculations employ newly constructed potential energy surfaces (PES), which take advantage of a novel method for using the large set of experimental energy levels for H216O to give high-quality predictions for H218O and H217O. This procedure greatly extends the energy range for which a PES can be accurately determined, allowing an accurate prediction of higher lying energy levels than are currently known from direct laboratory measurements. This PES is combined with a high-accuracy, ab initio dipole moment surface of water in the computation of all energy levels, transition frequencies and associated Einstein A coefficients for states with rotational excitation up to J = 50 and energies up to 30 000 cm-1. The resulting HotWat78 line lists complement the well-used BT2 H216O line list. Full line lists are made available online as Supporting Information and at www.exomol.com.

  16. Three-dimensional representations of complex carbohydrates and polysaccharides--SweetUnityMol: a video game-based computer graphic software.

    PubMed

    Pérez, Serge; Tubiana, Thibault; Imberty, Anne; Baaden, Marc

    2015-05-01

    A molecular visualization program tailored to deal with the range of 3D structures of complex carbohydrates and polysaccharides, either alone or in their interactions with other biomacromolecules, has been developed using advanced technologies elaborated by the video games industry. All the specific structural features displayed by the simplest to the most complex carbohydrate molecules have been considered and can be depicted. This concerns the monosaccharide identification and classification, conformations, location in single or multiple branched chains, depiction of secondary structural elements and the essential constituting elements in very complex structures. Particular attention was given to cope with the accepted nomenclature and pictorial representation used in glycoscience. This achievement provides a continuum between the most popular ways to depict the primary structures of complex carbohydrates to visualizing their 3D structures while giving the users many options to select the most appropriate modes of representations including new features such as those provided by the use of textures to depict some molecular properties. These developments are incorporated in a stand-alone viewer capable of displaying molecular structures, biomacromolecule surfaces and complex interactions of biomacromolecules, with powerful, artistic and illustrative rendering methods. They result in an open source software compatible with multiple platforms, i.e., Windows, MacOS and Linux operating systems, web pages, and producing publication-quality figures. The algorithms and visualization enhancements are demonstrated using a variety of carbohydrate molecules, from glycan determinants to glycoproteins and complex protein-carbohydrate interactions, as well as very complex mega-oligosaccharides and bacterial polysaccharides and multi-stranded polysaccharide architectures.

  17. Crystal structure of zwitterionic 4-(ammonio­methyl)­benzoate: a simple mol­ecule giving rise to a complex supra­molecular structure

    PubMed Central

    Atria, Ana María; Garland, Maria Teresa; Baggio, Ricardo

    2014-01-01

    The asymmetric unit of the title compound, C8H9NO2·H2O consists of an isolated 4-(ammonio­meth­yl)benzoate zwitterion derived from 4-amino­methyl­benzoic acid through the migration of the acidic proton, together with a water molecule of crystallization that is disordered over three sites with occupancy ratios (0.50:0.35:0.15). In the crystal structure, N—H⋯O hydrogen bonds together with π–π stacking of the benzene rings [centroid–centroid distance = 3.8602 (18) Å] result in a strongly linked, compact three-dimensional structure. PMID:25484753

  18. Crystal and mol-ecular structures of two silver(I) amidinates, including an unexpected co-crystal with a lithium amidinate.

    PubMed

    Wang, Sida; Harmgarth, Nicole; Liebing, Phil; Edelmann, Frank T

    2016-12-01

    The silver(I) amidinates bis-[μ-N(1),N(2)-bis-(propan-2-yl)benzamidinato-κ(2)N(1):N(2)]disilver(I), [Ag2(C13H19N2)2] or [Ag{PhC(N (i) Pr)2}]2 (1), and bis-(μ-N(1),N(2)-di-cyclohexyl-3-cyclo-propyl-propynamidinato-κ(2)N(1):N(2))disilver(I), [Ag2(C18H27N2)2] or [Ag{cyclo-C3H5-C≡C-C(NCy)2}]2 (2a), exist as centrosymmetric dimers with a planar Ag2N4C2 ring and a common linear coordination of the metal atoms in the crystalline state. Moiety 2a forms a co-crystal with the related lithium amidinate, namely bis-(μ-N(1),N(2)-di-cyclo-hexyl-3-cyclo-propyl-propynamidinato-κ(2)N(1):N(2))disilver(I) bis-(μ-N(1),N(2)-di-cyclo-hexyl-3-cyclo-propyl-propynamidinato-κ(3)N(1),N(2):N(1))bis-(tetra-hydro-furan-κO)lithium(I) toluene monosolvate, [Ag2(C18H27N2)2][Li2(C18H27N2)2(C4H8O)2]·C7H8 or [Ag{cyclo-C3H5-C≡C-C(NCy)2}]2[Li{cyclo-C3H5-C≡C-C(NCy)2}(THF)]2·C7H8, composed as 2a × 2b × toluene. The lithium moiety 2b features a typical ladder-type dimeric structure with a distorted tetra-hedral coordination of the metal atoms. In the silver(I) derivatives 1 and 2a, the amidinate ligand adopts a μ-κN:κN' coordination, while it is a μ-κN:κN:κN'-coordination in the case of lithium derivative 2b.

  19. Kinetic study on dissolution of UO 2 powders in nitric acid

    NASA Astrophysics Data System (ADS)

    Ikeda, Y.; Yasuike, Y.; Nishimura, K.; Hasegawa, S.; Takashima, Y.

    1995-09-01

    UO 2 powders of 90-150, 300-355, and 850-1000 μm were dissolved in HNO 3 solutions stirred at 300 rpm. Concentrations of HNO 2 in dissolvent solutions were held constant by supplying NaNO 2 solutions of appropriate concentrations at 0.2 ml/min. The dissolution reactions were analyzed on the assumptions that the UO 2 powders are spherical particles and homogeneously dissolved from their external surface. Dissolution rate constants (φ) in mol cm -2 min -1 were measured at various concentrations of HNO 3 and HNO 2, and temperatures. Furthermore, the effect of UO 22+ and NO 3- ions on the dissolution rate was also examined. It was found that the dissolution rate of UO 2 powders is not accelerated by UO 22+ ions and expressed as φ = ( ka + kb[HNO 2])[NO 3-] T2.3([NO 3-] T = total nitrate concentration). Activation energies ( ΔE≠) for ka and kb were evaluated to be 79.5 ± 6.7 and 36.8 ± 2.9 kJ/mol, respectively. The φ value at 80°C, [HNO 3] = 8M, and [HNO 2] = 0.024M (M = mol/dm 3) is 8.5 × 10 -6 mol cm -2 min -1.

  20. Biogeochemical and microbiological characteristic of the pockmark sediments, the Gdansk Deep, The Baltic Sea

    NASA Astrophysics Data System (ADS)

    Pimenov, Nikolay; Kanapatskiy, Timur; Sivkov, Vadim; Toshchakov, Stepan; Korzhenkov, Aleksei; Ulyanova, Marina

    2016-04-01

    Comparison of the biogeochemical and microbial features was done for the gas-bearing and background sediments as well as near-bottom water of the Gdansk Deep, The Baltic Sea. Data were received in October, 2015 during 64th cruise of the R/V Akademik Mstislav Keldysh. Gas-bearing sediments were sampled within the known pockmark (Gas-Point, depth 94 m). Background sediments area (BG-Point, depth 86 m) was located several km off the pockmark area. The sulphate concentration in the pore water of the surface sediment layer (0-5 cm) of Gas-Point was 9,7 mmol/l, and sharply decreased with depth (did not exceed 1 mmol/l deeper than 50 cm). The sulphate concentration decrease at BG-Point also took place but was not so considerable. Sulphate concentration decrease is typical for the organic rich sediments of the high productive areas, both as for the methane seep areas. Fast sulphate depletion occurs due to active processes of its microbial reduction by consortium of the sulphate-reduction bacteria, which may use low-molecular organic compounds or hydrogen, formed at the different stages of the organic matter destruction; as well as within the process of the anaerobic methane oxidation by consortium of the methane-trophic archaea and sulphate-reduction bacteria. Together with sulphate concentration decrease the methane content increase, typical for the marine sediments, occurred. At the Gas-Point the methane concentration varied within 10 μmol/dm3 in the surface layer till its maximum at sediment horizon of 65 cm (5 mmol/dm3), and decreased to 1.5 mmol/dm3 at depth of 300 cm. The BG-Point maximum values were defined at sediment horizon 6 cm (2,6 μmol/dm3). Methane sulfate transition zone at the Gas-Point sediments was at 25-35 cm depth; whereas it was not defined at the BG-Point mud. High methane concentration in the gas-bearing sediments results in the formation of the methane seep from the sediments to the near-bottom water. So the Gas-Point near-bottom waters were

  1. Kinetics and mechanism of superoxide radical reactions with some biologically important compounds in aqueous solutions. Pulse radiolysis

    NASA Astrophysics Data System (ADS)

    Revina, A. A.; Amiragova, M. I.; Volod'ko, V. V.; Vannikov, A. V.

    Microsecond pulse radiolysis of oxygenated aqueous solutions containing 0.02 mol dm -3 sodium formate and 2 mmol dm -3 phosphate buffer at pH 7 was used to generate superoxide anion radicals. The influence of some biologically important compounds upon the rate of O ⨪2 decay was monitored spectrophotometrically in the range of 245-300 nm. Hematoporphyrin (HP), hemin C (HC), catalase (Cat), cobalt sulfophthalocyanine (CoTSPc) were studied. Among the investigated compounds only Cat was found to show a high catalytic efficiency towards the self-decay of O ⨪2. A red shift of O ⨪2 absorption band and slowing down of its decay were observed to take place by adding HP or CoTSPc to the solutions containing formate ions in excess. This effect is associated with the formation of a transient superoxo-complex. An appearance of an intermediate species with absorption maxima at 350 nm and half-life of about 2s was observed to accompany the superoxo-complex of CoTSPc decay. In the aerated solution of HP the intensity of absorbance at 260 nm was found to be independent of the presence of formate ions.

  2. 241Am migration in a sandy aquifer studied by long-term column experiments.

    PubMed

    Artinger, Robert; Schuessler, Wolfram; Scherbaum, Franz; Schild, Dieter; Kim, Jae-Il

    2002-11-15

    The migration behavior of 241Am(III) in a sandy aquifer was studied under near-natural conditions by long-term column experiments of more than 1 year duration. Columns with 50 cm length and 5 cm in diameter were packed with aeolian quartz sand and equilibrated with two different groundwaters having an original dissolved organic carbon concentration (DOC) of 1.1 and 7.2 mg x dm(-3), respectively,from the Gorleben site (Lower Saxony, Germany). In each experiment, 1 cm3 of Am-spiked groundwater ([Am] = 0.2 to 2 micromol x dm(-3)) was injected into the column. The flow rate of the groundwater was adjusted to 0.28 m x d(-1). A small colloid-borne Am fraction was found to elute together with tritiated water. After 414 and 559 days, respectively, the experiments were terminated. Whereas the nonsorbing tracer of tritiated water would have covered a distance of about 350 m in that time period, the maximum of the Am activity was detected between 32 and 40 mm column length. Applying selective dissolution analysis to the sand surface, Am was found to be preferentially bound to iron hydroxide/oxide sites. From this Am distribution, a retardation factor R of about 10(4) was determined and compared to static batch experiments. The Am breakthrough was calculated forthe conditions of the column experiment

  3. INTERACTION OF LASER RADIATION WITH MATTER: Influence of Ca and Pb impurities on the bulk optical strength of ultrapure NaCl and KCl crystals

    NASA Astrophysics Data System (ADS)

    Vinogradov, An V.; Voszka, R.; Kovalev, Valerii I.; Faĭzullov, F. S.; Janszky, J.

    1987-06-01

    A significant increase (by a factor of about 3) of the bulk damage threshold in the case of interaction of CO2 laser radiation pulses with ultrapure NaCl and KCl crystals grown in a reactive atmosphere was observed on introduction of divalent metal ions Ca and Pb in concentrations of 10-5-10-6 mol/mol. Impurities were introduced in concentrations of 10-8-10-3 and 2×10-7-10-4 mol/mol into the melts of KCl and NaCl, respectively. The concentration of other impurities (including OH) did not exceed ~10-6 mol/mol. A physical model was developed to account for the observed dependence on the basis of an analogy between a system of colloidal particles and F centers in a crystal and a liquid-vapor system.

  4. Ionizing radiation induced degradation of monuron in dilute aqueous solution

    NASA Astrophysics Data System (ADS)

    Kovács, Krisztina; He, Shijun; Míle, Viktória; Földes, Tamás; Pápai, Imre; Takács, Erzsébet; Wojnárovits, László

    2016-07-01

    The decomposition of monuron was investigated in dilute aqueous solutions using pulse radiolysis and γ-radiolysis in order to identify the intermediates and final products. The main reaction takes place between monuron and the hydroxyl radicals yielding hydroxycyclohexadienyl type radicals with a second order rate constant of (7.4±0.2)×109 mol-1 dm3 s-1. In •OH reactions, the aminyl and phenoxyl radicals may also form. Dechlorination was observed in both hydroxyl radical and hydrated electron reactions. The •OH induced dechlorination reactions are suggested to occur through OH substitution or phenoxyl radical formation. The rate of oxidation is very high in the presence of dissolved oxygen. Some of the results are also supported by quantum chemical calculations.

  5. Water and ions in clays: Unraveling the interlayer/micropore exchange using molecular dynamics

    NASA Astrophysics Data System (ADS)

    Rotenberg, Benjamin; Marry, Virginie; Vuilleumier, Rodolphe; Malikova, Natalie; Simon, Christian; Turq, Pierre

    2007-11-01

    We present the first microscopic description of the exchange of water and ions between clay interlayers and microporosity. A force field based on ab-initio calculations is developed and used in classical molecular dynamics simulations. The latter allow to compute the potential of mean force for the interlayer/micropore exchange for water, Na + and Cs + cations and Cl - anions. For the simulated water content (water bilayer, with interlayer spacing 15.4 Å) and salt concentration in the micropore (0.52 mol dm -3) the exchange is found to be almost not activated for water and cations, whereas the entrance of an anion into the interlayer is strongly unfavorable ( ΔF˜9kT). Calculations of the diffusion tensor in the interlayer and in the micropore complete the study of the exchange dynamics.

  6. Surface film formation on nickel electrodes in a propylene carbonate solution at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Mogi, Ryo; Inaba, Minoru; Iriyama, Yasutoshi; Abe, Takeshi; Ogumi, Zempachi

    The effect of temperature on surface film formation on nickel electrode was studied in 1 mol dm -3 bis(perfluoroethylsulfonyl)imide dissolved in propylene carbonate by atomic force microscopy (AFM) and ac impedance spectroscopy. Cyclic voltammetry measurements revealed that electrolyte decomposition reactions are accelerated at elevated temperatures, especially at 60 and 80 °C. In situ AFM measurements showed that the film formation is fast and the resulting surface film is thicker at 80 °C than at room temperature. Furthermore, it was confirmed by ac impedance measurements that the resistance of surface film was very low at elevated temperatures. These results were discussed in relation to superior cycling characteristics of lithium deposition and dissolution at the elevated temperatures.

  7. Perovskite-type oxides La 1- xSr xMnO 3 for cathode catalysts in direct ethylene glycol alkaline fuel cells

    NASA Astrophysics Data System (ADS)

    Miyazaki, Kohei; Sugimura, Naotsugu; Matsuoka, Koji; Iriyama, Yasutoshi; Abe, Takeshi; Matsuoka, Masao; Ogumi, Zempachi

    Carbon-supported La 1- xSr xMnO 3 (LSM/C) was prepared by reversible homogeneous precipitation method, and its catalytic activities for oxygen reduction under the existence of ethylene glycol (EG) were investigated by using rotating disk electrode. LSM/C exhibited the high activity for oxygen reduction irrespective with the presence of EG, indicating that EG is not oxidized by LSM/C at the cathode side in the present system. Consequently, LSM/C can serve as a cathode catalyst in alkaline direct alcohol fuel cells with no crossover problem. Performance test for fuel cells operation also supported these results and showed cathodic polarization curves were not affected by the concentration of EG supplied to anode even at 5 mol dm -3.

  8. Solute effects on the interaction between water and ethanol in aged whiskey.

    PubMed

    Nose, Akira; Hojo, Masashi; Suzuki, Mika; Ueda, Tadaharu

    2004-08-25

    The hydrogen-bonding structure of water-ethanol in whiskey was examined on the basis of (1)H NMR chemical shifts of the OH of water and ethanol. Phenolic acids and aldehydes (gallic, vanillic, and syringic acids; vanillin and syringaldehyde) exhibited their structure-making effects regardless of the presence or absence of 0.1 or 0.2 mol dm(-3) acetic acid. The OH-proton chemical shifts were measured for 32 malt whiskey samples of a distillery, aged for 0-23 years in five different types of casks. The OH-proton chemical shift values of the whiskies shifted toward the lower field in proportion to their contents of total phenols. It can be concluded that the strength of the hydrogen bonding in aged whiskies is directly predominated by acidic and phenolic components gained in oak wood casks and not dependent on just the aging time.

  9. Silver(I) complex formation with cysteine, penicillamine, and glutathione.

    PubMed

    Leung, Bonnie O; Jalilehvand, Farideh; Mah, Vicky; Parvez, Masood; Wu, Qiao

    2013-04-15

    The complex formation between silver(I) and cysteine (H2Cys), penicillamine (H2Pen), and glutathione (H3Glu) in alkaline aqueous solution was examined using extended X-ray absorption fine structure (EXAFS) and (109)Ag NMR spectroscopic techniques. The complexes formed in 0.1 mol dm(-3) Ag(I) solutions with cysteine and penicillamine were investigated for ligand/Ag(I) (L/Ag) mole ratios increasing from 2.0 to 10.0. For the series of cysteine solutions (pH 10-11) a mean Ag-S bond distance of 2.45 ± 0.02 Å consistently emerged, while for penicillamine (pH 9) the average Ag-S bond distance gradually increased from 2.40 to 2.44 ± 0.02 Å. EXAFS and (109)Ag NMR spectra of a concentrated Ag(I)-cysteine solution (C(Ag(I)) = 0.8 mol dm(-3), L/Ag = 2.2) showed a mean Ag-S bond distance of 2.47 ± 0.02 Å and δ((109)Ag) 1103 ppm, consistent with prevailing, partially oligomeric AgS3 coordinated species, while for penicillamine (C(Ag(I)) = 0.5 mol dm(-3), L/Ag = 2.0) the mean Ag-S bond distance of 2.40 ± 0.02 Å and δ((109)Ag) 922 ppm indicate that mononuclear AgS2 coordinated complexes dominate. For Ag(I)-glutathione solutions (C(Ag(I)) = 0.01 mol dm(-3), pH ∼11), mononuclear AgS2 coordinated species with a mean Ag-S bond distance of 2.36 ± 0.02 Å dominate for L/Ag mole ratios from 2.0 to 10.0. The crystal structure of the silver(I)-cysteine compound (NH4)Ag2(HCys)(Cys)·H2O (1) precipitating at pH ∼10 was solved and showed a layer structure with both AgS3 and AgS3N coordination to the cysteinate ligands. A redetermination of the crystal structure of Ag(HPen)·H2O (2) confirmed the proposed digonal AgS2 coordination environment to bridging thiolate sulfur atoms in polymeric intertwining chains forming a double helix. A survey of Ag-S bond distances for crystalline Ag(I) complexes with S-donor ligands in different AgS2, AgS2(O/N), and AgS3 coordination environments was used, together with a survey of (109)Ag NMR chemical shifts, to assist assignments of the Ag

  10. The γ-irradiation of aqueous acetic acid-clay suspensions

    NASA Astrophysics Data System (ADS)

    Negrón-Mendoza, Alicia; Navarro-González, Rafael

    1990-09-01

    γ-radiolysis of 0.8 mol dm-3 aqueous, oxygen-free acetic acid solutions was investigated in the presence or absence of Na-montmorillonite (1 3 g per 10 cm-3). The systems were irradiated at their natural pH (3.5), and 25 °C in a dose range from 0.01 to 500 kGy. H2, CH4, CO, CO2, and a variety of polycarboxylic acids were formed in all systems. The major features of the radiolysis in the presence of clays were: (1) More solute molecules were decomposed; (2) Carbon dioxide was produced in higher yield; (3) The yield of methane was unaffected; and (4) 44% less polycarboxylic acids were formed. Three possible mechanisms that could account for the observed changes are suggested. The results are important in understanding heterogeneous processes in radiation catalysis and might be significant to prebiotic chemistry.

  11. Muonium reactions with chloroacetic acid in water: Contrasts with H atoms and hydrated electrons

    NASA Astrophysics Data System (ADS)

    Stadlbauer, John M.; Venkateswaran, Krishnan; Walker, David C.

    1997-09-01

    Muonium atoms react with chloroacetic acid and chloroacetate ions in dilute aqueous solution with rate constants of 2.3 × 10 6 and 9.1 × 10 5 dm 3 mol -1 s -1 respectively. These are compared with the reactions of 1H atoms (and e aq-) and discussed in terms of a pair of competing kinetic isotope effects. Muonium reacts at least eight times faster than H overall, and probably 28 times faster in forming Cl -. It behaves as a nucleophile, thus resembling e aq- more than H, in reacting faster with the acid than the anion. Muonium's reactions must be governed to a considerable extent by quantum-mechanical effects arising from its very small mass.

  12. Indirect voltammetric detection of fluoride ions in toothpaste on a comb-shaped interdigitated microelectrode array.

    PubMed

    Cernanská, Monika; Tomcík, Peter; Jánosíková, Zuzana; Rievaj, Miroslav; Bustin, Dusan

    2011-02-15

    A novel technique based on dynamic electrochemistry for the detection of fluoride ions was developed. It is based on its strong complexation with ferric ion. Formed fluoroferric complex is cathodically inactive at the potential of the reduction of free ferric aquo ion. The voltammetric and amperometric response of platinum comb-shaped interdigitated microelectrode array is decreased after fluoride addition. This decrease serves for the quantification of fluoride ions added to the solution. The detection limit of 4.5×10(-5) mol dm(-3) was achieved when one of the segments of interdigitated microelectrode array (IDA) was used as an indicating electrode. The detection limit is about one order of magnitude lower than in the case of conventional platinum macroelectrode. In comparison with ISE electrodes this method is faster and also avoiding large error resulting from the antilogarithmization of ISE Nerstian response. The method was applied to the analysis of toothpaste.

  13. Flue gas treatment for SO2 removal with air-sparged hydrocyclone technology.

    PubMed

    Bokotko, Romuald P; Hupka, Jan; Miller, Jan D

    2005-02-15

    Laboratory results from an initial study on the removal of SO2 from gas mixtures are reported using air-sparged hydrocyclone (ASH) technology. Tap water and alkaline solutions were used for absorption, and the influence of gas flow rate, water flow rate, and length of the ASH unit were investigated. The research results indicate thatthe air-sparged hydrocyclone can be used as a highly efficient absorber for SO2 emissions. The ASH allows for 97% SO2 removal using water alone for sulfur dioxide content in the gas phase of 5 g/m3. All SO2 is removed in weakly alkaline solution (0.01 mol NaOH/dm3).

  14. Radiolysis of aqueous solutions of acetic acid in the presence of Na-montmorillonite

    NASA Technical Reports Server (NTRS)

    Navarro-Gonzalez, R.; Negron-Mendoza, A.; Ramos, S.; Ponnamperuma, C.

    1990-01-01

    The gamma-irradiation of 0.8 mol dm-3 aqueous, oxygen-free acetic acid solutions was investigated in the presence or absence of Na-montmorillonite. H2, CH4, CO, CO2, and several polycarboxylic acids were formed in all systems. The primary characteristics observed in the latter system were: (1) Higher yield of the decomposition of acetic acid; (2) Lower yield of the formation of polycarboxylic acids; (3) No effect on the formation of methane; (4) Higher yield of the formation of carbon dioxide; and (5) The reduction of Fe3+ in the octahedral sites of Na-montmorillonite. A possible reaction scheme was proposed to account for the observed changes. The results are important in understanding heterogeneous processes in radiation catalysis and might be significant to prebiotic chemistry.

  15. Electrochemical Behavior of Titanium(II) Ion in a Purified Calcium Chloride Melt

    NASA Astrophysics Data System (ADS)

    Kang, Min Ho; Song, Jianxun; Zhu, Hongmin; Jiao, Shuqiang

    2014-09-01

    Cyclic voltammetry, chronopotentiometry, and square wave voltammetry were used to investigate electrochemical behavior of Ti(II) ion in a purified CaCl2 melt at a temperature of 1173 K (900 °C). The result indicated that the cathodic reduction of Ti(II) ion in the melt was a one-step quasi-reversible process controlled by the diffusion. The diffusion coefficient was determined in a CaCl2-TiCl(0.5 mol/dm3) at 1173 K (900 °C). The work also demonstrated the feasibility of producing metallic titanium in the as-prepared CaCl2-TiCl2 melts through galvanostatic electrolysis.

  16. Electrochemical Behavior of Titanium(II) Ion in a Purified Calcium Chloride Melt

    NASA Astrophysics Data System (ADS)

    Kang, Min Ho; Song, Jianxun; Zhu, Hongmin; Jiao, Shuqiang

    2015-02-01

    Cyclic voltammetry, chronopotentiometry, and square wave voltammetry were used to investigate electrochemical behavior of Ti(II) ion in a purified CaCl2 melt at a temperature of 1173 K (900 °C). The result indicated that the cathodic reduction of Ti(II) ion in the melt was a one-step quasi-reversible process controlled by the diffusion. The diffusion coefficient was determined in a CaCl2-TiCl(0.5 mol/dm3) at 1173 K (900 °C). The work also demonstrated the feasibility of producing metallic titanium in the as-prepared CaCl2-TiCl2 melts through galvanostatic electrolysis.

  17. Properties of graphite-stainless steel composite in bipolar plates in simulated anode and cathode environments of PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Włodarczyk, Renata

    2014-09-01

    The use of a graphite-stainless steel composite as bipolar plates (BP) in polymer electrolyte membrane fuel cells (PEMFCs) has been evaluated. The study covers measurements of mechanical properties, microstructural examination, analysis of surface profile, wettability, porosity and corrosion resistance of the composite. The corrosion properties of the composite were examined in 0.1 mol·dm-3 H2SO4 + 2 ppm F- saturated with H2 or with O2 and in solutions with different pH: in Na2SO4+ 2 ppm F- (pH = 1.00, 3.00, 5.00) at 80 °C. The performed tests indicate that the graphite modified with stainless steel can be a good choice to be used as a bipolar plate in PEM fuel cells.

  18. Contribution to diagnostics/prognostics of tuberculosis in children. I. New methods of assaying zinc and simultaneously copper and zinc in diluted sera by flame atomic-absorption spectrometry.

    PubMed

    Luterotti, Svjetlana; Kordić, Tončica Vukman; Dodig, Slavica

    2015-09-01

    In an attempt to provide a reliable status of metal ions in children, new methods of analysis of children's sera are proposed. New flame atomic-absorption spectrometric (FAAS) methods are simple, cost- and time-effective and, above all, labor-, reagent- and sample-saving. Two methods were suggested: method A for simultaneous determination of Cu and Zn from 5-fold diluted sera, and method B, for assaying zinc alone in 10-fold diluted samples. Both methods are based on a single-step sample pretreatment (deproteinization with 3 mol dm-3 HCl). Method A uses a single-step calibration with a mixed standard. The main advantage of method B is an additional reduction in sample consumption. Both methods were fully validated against reference methods. Accuracy, sensitivity and precision have proven them to be comparable to the reference methods in terms of analytical performance, and applicable to analyses of children's sera.

  19. Kinetics and mechanism of oxidation of chondroitin-4-sulfate polysaccharide by chromic acid in aqueous perchlorate solutions.

    PubMed

    Hassan, Refat; Ibrahim, Samia; Dahy, Abdel Rahman; Zaafarany, Ishaq; Tirkistani, Fahd; Takagi, Hideo

    2013-02-15

    The kinetics of chromic acid oxidation of chondroitin-4-sulfate polysaccharide as sulfated carbohydrates at a constant ionic strength of 4.0 mol dm(-3) has been investigated, spectrophotometrically. The reaction kinetics showed a first-order dependence in chromic acid and fractional-first-order kinetics with respect to the chondroitin-4-sulfate concentration. The influence of [H(+)] on the reaction rates showed that the oxidation process is acid-catalyzed. Added Mn(2+) ions indicated the formation of Cr(IV) as intermediate species. A kinetic evidence for formation of 1:1 intermediate complex was revealed. The kinetic parameters have been evaluated and a tentative reaction mechanism in good consistent with the kinetic results obtained is discussed.

  20. Synthesis of novel amorphous calcium carbonate by sono atomization for reactive mixing.

    PubMed

    Kojima, Yoshiyuki; Kanai, Makoto; Nishimiya, Nobuyuki

    2012-03-01

    Droplets of several micrometers in size can be formed in aqueous solution by atomization under ultrasonic irradiation at 2 MHz. This phenomenon, known as atomization, is capable of forming fine droplets for use as a reaction field. This synthetic method is called SARM (sono atomization for reactive mixing). This paper reports on the synthesis of a novel amorphous calcium carbonate formed by SARM. The amorphous calcium carbonate, obtained at a solution concentration of 0.8 mol/dm(3), had a specific surface area of 65 m(2)/g and a composition of CaCO(3)•0.5H(2)O as determined using thermogravimetric/differential thermal analysis (TG-DTA). Because the ACC had a lower hydrate composition than conventional amorphous calcium carbonate (ACC), the ACC synthesized in this paper was very stable at room temperature.