Sample records for f-element metallocene dichlorides

  1. Theoretical and experimental prediction of the redox potentials of metallocene compounds

    NASA Astrophysics Data System (ADS)

    Li, Ya-Ping; Liu, Hai-Bo; Liu, Tao; Yu, Zhang-Yu

    2017-11-01

    The standard redox electrode potential ( E°) values of metallocene compounds are obtained theoretically with density functional theory (DFT) method at B3LYP/6-311++G( d, p) level and experimentally with cyclic voltammetry (CV). The theoretical E° values of metallocene compounds are in good agreement with experimental ones. We investigate the substituent effects on the redox properties of metallocene compounds. Among the four metallocene compounds, the E° values is largest for titanocene dichloride and smallest for ferrocene.

  2. Coordination Chemistry of Disilylated Germylenes with Group 4 Metallocenes

    PubMed Central

    2013-01-01

    Reaction of the PEt3 adduct of a disilylated five-membered cyclic germylene with group 4 metallocene dichlorides in the presence of magnesium led to the formation of the respective germylene metallocene phosphine complexes of titanium, zirconium, and hafnium. Attempts to react the related NHC adduct of a disilylated four-membered cyclic germylene under the same conditions with Cp2TiCl2 did not give the expected germylene NHC titanocene complex. This complex was, however, obtained in the reaction of Cp2Ti(btmsa) with the NHC germylene adduct. A computational analysis of the structure of the group 4 metallocene germylene complexes revealed the multiple-bond character of the M–Ge(II) linkage, which can be rationalized with the classical σ-donor/π-acceptor interaction. The strength of the M–Ge(II) bond increases descending group 4. PMID:23874053

  3. Radium-223 dichloride bone-targeted alpha particle therapy for hormone-refractory breast cancer metastatic to bone

    PubMed Central

    2014-01-01

    Background Hormone-refractory breast cancer metastatic to bone is a clinically challenging disease associated with high morbidity, poor prognosis, and impaired quality of life owing to pain and skeletal-related events. In a preclinical study using a mouse model of breast cancer and bone metastases, Ra-223 dichloride was incorporated into bone matrix and inhibited proliferation of breast cancer cells and differentiation of osteoblasts and osteoclasts (all P values < .001) in vitro. Ra-223 dichloride also induced double-strand DNA breaks in cancer cells in vivo. Methods The US Food and Drug Administration recently approved radium-223 (Ra-223) dichloride (Ra-223; Xofigo injection) alpha-particle therapy for the treatment of symptomatic bone metastases in patients with castration-resistant prostate cancer. On the basis of a strong preclinical rationale, we used Ra-223 dichloride to treat bone metastases in a patient with breast cancer. Results A 44-year-old white woman with metastatic breast cancer who was estrogen receptor–positive, BRCA1-negative, BRCA2-negative, PIK3CA mutation (p.His1047Arg) positive presented with diffuse bony metastases and bone pain. She had hormone refractory and chemotherapy refractory breast cancer. After Ra-223 therapy initiation her bone pain improved, with corresponding decrease in tumor markers and mixed response in 18F-FDG PET/CT and 18F-NaF bone PET/CT. The patient derived clinical benefit from therapy. Conclusion We have shown that Ra-223 dichloride can be safely administered in a patient with hormone-refractory bone metastasis from breast cancer at the US FDA–approved dose for prostate cancer. Furthermore, because the treatment did not cause any drop in hematologic parameters, it has the potential to be combined with other radiosensitizing therapies, which may include chemotherapy or targeted therapies. Given that Ra-223 dichloride is already commercially available, this case report may help future patients and provide a rationale for initiating clinical research in the use of Ra-223 dichloride to treat bone metastasis from breast cancer. A randomized clinical trial is needed to provide evidence of efficacy, safety, and good outcomes. PMID:25243101

  4. Metal atom dynamics in superbulky metallocenes: a comparison of (Cp(BIG))2Sn and (Cp(BIG))2Eu.

    PubMed

    Harder, Sjoerd; Naglav, Dominik; Schwerdtfeger, Peter; Nowik, Israel; Herber, Rolfe H

    2014-02-17

    Cp(BIG)2Sn (Cp(BIG) = (4-n-Bu-C6H4)5cyclopentadienyl), prepared by reaction of 2 equiv of Cp(BIG)Na with SnCl2, crystallized isomorphous to other known metallocenes with this ligand (Ca, Sr, Ba, Sm, Eu, Yb). Similarly, it shows perfect linearity, C-H···C(π) bonding between the Cp(BIG) rings and out-of-plane bending of the aryl substituents toward the metal. Whereas all other Cp(BIG)2M complexes show large disorder in the metal position, the Sn atom in Cp(BIG)2Sn is perfectly ordered. In contrast, (119)Sn and (151)Eu Mößbauer investigations on the corresponding Cp(BIG)2M metallocenes show that Sn(II) is more dynamic and loosely bound than Eu(II). The large displacement factors in the group 2 and especially in the lanthanide(II) metallocenes Cp(BIG)2M can be explained by static metal disorder in a plane parallel to the Cp(BIG) rings. Despite parallel Cp(BIG) rings, these metallocenes have a nonlinear Cpcenter-M-Cpcenter geometry. This is explained by an ionic model in which metal atoms are polarized by the negatively charged Cp rings. The extent of nonlinearity is in line with trends found in M(2+) ion polarizabilities. The range of known calculated dipole polarizabilities at the Douglas-Kroll CCSD(T) level was extended with values (atomic units) for Sn(2+) 15.35, Sm(2+)(4f(6) (7)F) 9.82, Eu(2+)(4f(7) (8)S) 8.99, and Yb(2+)(4f(14) (1)S) 6.55. This polarizability model cannot be applied to predominantly covalently bound Cp(BIG)2Sn, which shows a perfectly ordered structure. The bent geometry of Cp*2Sn should therefore not be explained by metal polarizability but is due to van der Waals Cp*···Cp* attraction and (to some extent) to a small p-character component in the Sn lone pair.

  5. Metallocene Antimalarials: The Continuing Quest

    PubMed Central

    Blackie, Margaret A. L.; Chibale, Kelly

    2008-01-01

    Over the last decade, a significant body of research has been developed around the inclusion of a metallocene moiety into known antimalarial compounds. Ferroquine is the most successful of these compounds. Herein, we describe our contribution to metallocene antimalarials. Our approach has sought to introduce diversity sites in the side chain of ferroquine in order to develop a series of ferroquine derivatives. The replacement of the ferrocenyl moiety with ruthenocene has given rise to ruthenoquine and a modest series of analogues. The reaction of ferroquine and selected analogues with Au(PPh3)NO3, Au(C6F5)(tht), and [Rh(COD)Cl2] has resulted in a series of heterobimetallic derivatives. In all cases, compounds have been evaluated for in vitro antiplasmodial activity in both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum. Preliminary structure-activity relationships have been delineated. PMID:18274662

  6. C6, C7, and C8 perfluoroalkyl-substituted phosphinic acids.

    PubMed

    Singh, R P; Shreeve, J M

    2000-04-17

    Reaction of red phosphorus with RfI in a 1:2 molar ratio at 230 degrees C led to the formation of a mixture of (Rf)2PI and (Rf)PI2 (Rf = C6F13, C7F15, C8F17) in about a 70:30 ratio, respectively. These mixtures were separated by vacuum distillation. (Rf)2PI (Rf = C6F13, C7F15) are yellow liquids whereas (C8F17)2PI is a yellow solid. Oxidation of (Rf)2PI with excess NO2 led to (Rf)2P(O)OH (Rf = C6F13, C7F15, C8F17) in > 90% isolated yields after aqueous hydrolysis of the anhydride intermediates. These highly fluorinated phosphinic acids are white solids with sharp melting points and are highly soluble in methyl sulfoxide (DMSO) and 1,1,2-trichlorotrifluoroethane. However, solubility in chloroform and methylene dichloride is low. These perfluoroalkylphosphinic acids were characterized by IR, NMR (1H, 19F, and 31P), and mass spectra and elemental analysis.

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

    Rotman, D.

    Exxon chemical says it has made linear low-density polyethylene (LLDPE) using metallocene catalysts at its world-scale gas-phase plant in Mont Belvieu, TX. Exxon also says it has received a broad US patent that covers the use of metallocenes in gas-phase reactors that use condensing mode technology and that it plans to license the know-how. The moves, say industry experts, greatly strengthen Exxon`s position in metallocenes, particularly in pushing metallocene-based PE into commodity markets. The use of gas-phase technology {open_quotes}had to happen{close_quotes} to allow metallocene polymers to compete as commodities, says David Highfield, v.p. at Catalyst Consultants (Spring House, PA). {open_quotes}It`smore » very important and very significant in widening the scope of [metallocene] technology.{close_quotes}« less

  8. Method of preparing metallocene compounds

    DOEpatents

    Rosenblum, Myron; Matchett, Stephen A.

    1992-01-01

    This invention describes a novel method of preparing metallocene compounds. The invention is based on synthesis of novel bis cyclopentadienides that, under appropriate conditions, will either encapsulate a transition metal to produce a metallocene such as ferrocene, or ferrocene derivative, or will yield a polymeric metallocene. Compounds produced by this process are useful as catalysts in propulsion systems, or as anti-knock compounds in gasolines.

  9. Recent Advances of Metallocenes for Medicinal Chemistry.

    PubMed

    Santos, Miguel M; Bastos, Pedro; Catela, Isabelle; Zalewska, Karolina; Branco, Luis C

    2017-01-01

    The recent advances for the synthesis and application of different metallocenes for Medicinal Chemistry is reviewed. This manuscript presents the different metallocene scaffolds, with special emphasis on ferrocene derivatives, and their potential pharmaceutical application. Over the last years, the synthesis of new metallocene compounds and their biological and medicinal effects against some types of diseases (e.g. anti-tumoral, antibiotics, anti-viral) have been reported. From the medicinal point of view, the attractive properties of metallocene derivatives, such as their high stability, low toxicity and appealing redox behaviors are particularly relevant. This area has attracted many researchers as well as the pharmaceutical industry due to the promising results of some metallocenes, in particular ferrocene compounds, in breast cancer and malaria. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Non-metallocene organometallic complexes and related methods and systems

    DOEpatents

    Agapie, Theodor; Golisz, Suzanne Rose; Tofan, Daniel; Bercaw, John E.

    2010-12-07

    A non-metallocene organometallic complex comprising a tridentate ligand and a metal bonded to a tridentate ligand, wherein two substituted aryl groups in the tridentate ligand are connected to a cyclic group at the ortho position via semi-rigid ring-ring linkages, and selected so to provide the resulting non-metallocene organometallic complex with a C.sub.S geometry, a C.sub.1 geometry, a C.sub.2 geometry or a C.sub.2v geometry. Method for performing olefin polymerization with a non-metallocene organometallic complex as a catalyst, related catalytic systems, tridentate ligand and method for providing a non-metallocene organometallic complex.

  11. An Organolanthanide Building Block Approach to Single-Molecule Magnets.

    PubMed

    Harriman, Katie L M; Murugesu, Muralee

    2016-06-21

    Single-molecule magnets (SMMs) are highly sought after for their potential application in high-density information storage, spintronics, and quantum computing. SMMs exhibit slow relaxation of the magnetization of purely molecular origin, thus making them excellent candidates towards the aforementioned applications. In recent years, significant focus has been placed on the rare earth elements due to their large intrinsic magnetic anisotropy arising from the near degeneracy of the 4f orbitals. Traditionally, coordination chemistry has been utilized to fabricate lanthanide-based SMMs; however, heteroatomic donor atoms such as oxygen and nitrogen have limited orbital overlap with the shielded 4f orbitals. Thus, control over the anisotropic axis and induction of f-f interactions are limited, meaning that the performance of these systems can only extend so far. To this end, we have placed considerable attention on the development of novel SMMs whose donor atoms are conjugated hydrocarbons, thereby allowing us to perturb the crystal field of lanthanide ions through the use of an electronic π-cloud. This approach allows for fine tuning of the anisotropic axis of the molecule, allowing this method the potential to elicit SMMs capable of reaching much larger values for the two vital performance measurements of an SMM, the energy barrier to spin reversal (Ueff), and the blocking temperature of the magnetization (TB). In this Account, we describe our efforts to exploit the inherent anisotropy of the late 4f elements; namely, Dy(III) and Er(III), through the use of cyclooctatetraenyl (COT) metallocenes. With respect to the Er(III) derivatives, we have seen record breaking success, reaching blocking temperatures as high as 14 K with frozen solution magnetometry. These results represent the first example of such a high TB being observed for a system with only a single spin center, formally known as a single-ion magnet (SIM). Our continued interrelationship between theoretical and experimental chemistry allows us to shed light on the mechanisms and electronic properties that govern the slow relaxation dynamics inherent to this unique set of SMMs, thus providing insight into the role by which both symmetry and crystal field effects contribute to the magnetic properties. As we look to the future success of such materials in practical devices, we must gain an understanding of how the 4f elements communicate magnetically, a subject upon which there is still limited knowledge. As such, we have described our work on coupling mononuclear metallocenes to generate new dinuclear SMMs. Through a building block approach, we have been able to gain access to new double,- triple- and quadruple-decker complexes that possess remarkable properties; exhibiting TB of 12 K and Ueff above 300 K. Our goal is to develop a fundamental platform from which to study 4f coupling, while maintaining and enhancing the strict axiality of the anisotropy of the 4f ions. This Account will present a successful strategy employed in the production of novel and high-performing SMMs, as well as a clear overview of the lessons learned throughout.

  12. Organo-Lewis acid as cocatalyst for cationic homogenous metallocene Ziegler-Natta olefin polymerizations

    DOEpatents

    Marks, Tobin J.; Chen, You-Xian

    2000-01-01

    The synthesis of the organo-Lewis acid perfluorobiphenylborane (PBB) and the activation of metallocenes for the formation of a variety of highly active homogeneous Ziegler-Natta metallocene olefin polymerization, copolymerization and ring-opening polymerization catalysts is described.

  13. Sterically shielded diboron-containing metallocene olefin polymerization catalysts

    DOEpatents

    Marks, Tobin J.; Ja, Li; Yang, Xinmin

    1995-09-05

    A non-coordinating anion, preferably containing a sterically shielded diboron hydride, if combined with a cyclopenta-dienyl-substituted metallocene cation component, such as a zirconocene metallocene, is a useful olefin polymerization catalyst component. The anion preferably has the formula ##STR1## where R is branched lower alkyl, such as t-butyl.

  14. Preparation, characterization, and activity of α-Ti(HPO4)2 supported metallocene catalysts

    NASA Astrophysics Data System (ADS)

    Shi, Yasai; Yuan, Yuan; Xu, Qinghong; Yi, Jianjun

    2016-10-01

    A series of heterogeneous catalysts by loading metallocenes on surface of α-Ti(HPO4)2, a kind of solid acid, has been synthesized. Polymerization of alkenes, including ethylene and propylene, based on participation of the heterogeneous catalysts were studied and the results were compared to metallocenes supported on silica gel, α-Zr(HPO4)2 and clay. Higher catalytic activity, larger polymer molecular weight and narrow distribution of polymer molecular weight were obtained. Acidic strength of the support and its influence to metallocenes were studied to discover intrinsic factors in the polymerizations.

  15. Encapsulant Material For Solar Cell Module And Laminated Glass Applications

    DOEpatents

    Hanoka, Jack I.

    2000-09-05

    An encapsulant material includes a layer of metallocene polyethylene disposed between two layers of ionomer. More specifically, the layer of metallocene polyethylene is disposed adjacent a rear surface of the first ionomer layer, and a second layer of ionomer is disposed adjacent a rear surface of the layer of metallocene polyethylene. The encapsulant material can be used in solar cell module and laminated glass applications.

  16. A Heterobimetallic Complex With an Unsupported Uranium(III)-Aluminum(I) Bond: (CpSiMe3)3U-AlCp* (Cp* = C5Me5)

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

    Minasian, Stefan; Krinsky Ph.D., Jamin; Williams, Valerie

    2008-07-23

    The discovery of molecular metal-metal bonds has been of fundamental importance to the understanding of chemical bonding. For the actinides, examples of unsupported metal-metal bonds are relatively uncommon, consisting of Cp{sub 3}U-SnPh{sub 3}, and several actinide-transition metal complexes. Traditionally, bonding in the f-elements has been described as electrostatic; however, elucidating the degree of covalency is a subject of recent research. In carbon monoxide complexes of the trivalent uranium metallocenes, decreased {nu}{sub CO} values relative to free CO suggest that the U(III) atom acts as a {pi}-donor. Ephritikhine and coworkers have demonstrated that {pi}-accepting ligands can differentiate trivalent lanthanide and actinidemore » ions, an effect that renders this chemistry of interest in the context of nuclear waste separation technology.« less

  17. Alkaline earth metallocenes coordinated with ester pendants: synthesis, structural characterization, and application in metathesis reactions.

    PubMed

    Li, Heng; Zhang, Wen-Xiong; Xi, Zhenfeng

    2013-09-16

    A variety of ester-substituted cyclopentadiene derivatives have been synthesized by one-pot reactions of 1,4-dilithio-1,3-butadienes, CO, and acid chlorides. Direct deprotonation of the ester-substituted cyclopentadienes with Ae[N(SiMe3 )2 ]2 (Ae=Ca, Sr, Ba) efficiently generated members of a new class of heavier alkaline earth (Ca, Sr, Ba) metallocenes in good to excellent yields. Single-crystal X-ray structural analysis demonstrated that these heavier alkaline earth metallocenes incorporated two intramolecularly coordinated ester pendants and multiply-substituted cyclopentadienyl ligands. The corresponding transition metal metallocenes, such as ferrocene derivatives and half-sandwich cyclopentadienyl tricarbonylrhenium complexes, could be generated highly efficiently by metathesis reactions. The multiply-substituted cyclopentadiene ligands bearing an ester pendant, and the corresponding heavier alkaline earth and transition-metal metallocenes, may have further applications in coordination chemistry, organometallic chemistry, and organic synthesis. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Human tumour xenografts in nude mice: chemotherapy trials with titanocene dichloride in different dosages.

    PubMed

    Villena-Heinsen, C; Friedrich, M; Ertan, A K; Schmidt, W

    1998-01-01

    In this study new cytostatic therapies with titanocene dichloride in different dosages for the treatment of ovarian cancer are analyzed on human tumour xenografts in nude mice. The aim was to compare the effects of different dosages of titanocene dichloride on the growth of human tumour xenografts and nude mice body weight. Biopsy material from one human ovarian carcinoma was expanded and transplanted into 52 nude mice. The treatment protocol included one experiment that consisted of the following six treatment groups: titanocene dichloride 3 x 10 mg/kg, titanocene dichloride 3 x 20 mg/kg, titanocene dichloride 3 x 30 mg/kg, titanocene dichloride 1 x 30 mg/kg, titanocene dichloride 1 x 40 mg/kg and a control group treated with 0.9% saline. Treatment groups were evaluated in terms of average daily increase in tumour volume and average daily body weight increase on nude mice. The slope factors alpha and beta of the body weight and tumour volume changes were calculated. Titanocene dichloride in the dosage of 3 x 30 mg/kg and 3 x 20 mg/kg brought about a significant reduction in tumour volume (p < 0.05) compared to the control group and to the treatment group under medication with titanocene dichloride 1 x 30 mg/kg. There were no significant changes in the body weight of nude mice. We found titanocene dichloride to be effective in the reduction of tumour volume increase in nude mice. Titanocene dichloride could be an active chemotherapeutic drug in women with ovarian carcinoma not responding to standard therapies.

  19. 40 CFR 721.9973 - Zirconium dichlorides (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Zirconium dichlorides (generic). 721... Substances § 721.9973 Zirconium dichlorides (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as zirconium dichlorides (PMNs P...

  20. 21 CFR 573.440 - Ethylene dichloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethylene dichloride. 573.440 Section 573.440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additive Listing § 573.440 Ethylene dichloride. The food additive ethylene dichloride may be safely used in...

  1. 21 CFR 173.230 - Ethylene dichloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene dichloride. 173.230 Section 173.230 Food... Solvents, Lubricants, Release Agents and Related Substances § 173.230 Ethylene dichloride. A tolerance of 30 parts per million is established for ethylene dichloride in spice oleoresins when present therein...

  2. 21 CFR 573.440 - Ethylene dichloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.440 Ethylene dichloride. The food additive ethylene dichloride may be safely used in... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ethylene dichloride. 573.440 Section 573.440 Food...

  3. 21 CFR 573.440 - Ethylene dichloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.440 Ethylene dichloride. The food additive ethylene dichloride may be safely used in... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ethylene dichloride. 573.440 Section 573.440 Food...

  4. 21 CFR 573.440 - Ethylene dichloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.440 Ethylene dichloride. The food additive ethylene dichloride may be safely used in... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ethylene dichloride. 573.440 Section 573.440 Food...

  5. 21 CFR 573.440 - Ethylene dichloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.440 Ethylene dichloride. The food additive ethylene dichloride may be safely used in... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ethylene dichloride. 573.440 Section 573.440 Food...

  6. Encapsulant Material For Solar Cell Module And Laminated Glass Applications

    DOEpatents

    Hanoka, Jack I.; Klemchuk, Peter P.

    2001-02-13

    An encapsulant material includes a layer of metallocene polyethylene disposed between two layers of an acid copolymer of polyethylene. More specifically, the layer of metallocene polyethylene is disposed adjacent a rear surface of the first layer of the acid copolymer of polyethylene, and a second layer of the acid copolymer of polyethlene is disposed adjacent a rear surface of the layer of metallocene polyethylene. The encapsulant material can be used in solar cell module and laminated glass applications.

  7. 40 CFR Table 4 to Subpart F of... - Organic Hazardous Air Pollutants Subject to Cooling Tower Monitoring Requirements in § 63.104

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Dichlorobenzidine (3,3″-) 91941 Dichloroethane (1,2-) (Ethylene dichloride) (EDC) 107062 Dichloroethyl ether (Bis(2... Ethyl acrylate 140885 Ethylbenzene 100414 Ethyl chloride (Chloroethane) 75003 Ethylene dibromide (Dibromoethane) 106934 Ethylene glycol dimethyl ether 110714 Ethylene glycol monobutyl ether 111762 Ethylene...

  8. Carbon K-edge X-ray absorption spectroscopy and time-dependent density functional theory examination of metal-carbon bonding in metallocene dichlorides.

    PubMed

    Minasian, Stefan G; Keith, Jason M; Batista, Enrique R; Boland, Kevin S; Kozimor, Stosh A; Martin, Richard L; Shuh, David K; Tyliszczak, Tolek; Vernon, Louis J

    2013-10-02

    Metal-carbon covalence in (C5H5)2MCl2 (M = Ti, Zr, Hf) has been evaluated using carbon K-edge X-ray absorption spectroscopy (XAS) as well as ground-state and time-dependent hybrid density functional theory (DFT and TDDFT). Differences in orbital mixing were determined experimentally using transmission XAS of thin crystalline material with a scanning transmission X-ray microscope (STXM). Moving down the periodic table (Ti to Hf) has a marked effect on the experimental transition intensities associated with the low-lying antibonding 1a1* and 1b2* orbitals. The peak intensities, which are directly related to the M-(C5H5) orbital mixing coefficients, increase from 0.08(1) and 0.26(3) for (C5H5)2TiCl2 to 0.31(3) and 0.75(8) for (C5H5)2ZrCl2, and finally to 0.54(5) and 0.83(8) for (C5H5)2HfCl2. The experimental trend toward increased peak intensity for transitions associated with 1a1* and 1b2* orbitals agrees with the calculated TDDFT oscillator strengths [0.10 and 0.21, (C5H5)2TiCl2; 0.21 and 0.73, (C5H5)2ZrCl2; 0.35 and 0.69, (C5H5)2HfCl2] and with the amount of C 2p character obtained from the Mulliken populations for the antibonding 1a1* and 1b2* orbitals [8.2 and 23.4%, (C5H5)2TiCl2; 15.3 and 39.7%, (C5H5)2ZrCl2; 20.1 and 50.9%, (C5H5)2HfCl2]. The excellent agreement between experiment, theory, and recent Cl K-edge XAS and DFT measurements shows that C 2p orbital mixing is enhanced for the diffuse Hf (5d) and Zr (4d) atomic orbitals in relation to the more localized Ti (3d) orbitals. These results provide insight into how changes in M-Cl orbital mixing within the metallocene wedge are correlated with periodic trends in covalent bonding between the metal and the cyclopentadienide ancillary ligands.

  9. Highly tunable porous organic polymer (POP) supports for metallocene-based ethylene polymerization

    NASA Astrophysics Data System (ADS)

    Wang, Xiong; Li, Zhenyou; Han, Xiaoyu; Han, Zhengang; Bai, Yongxiao

    2017-10-01

    Porous organic Polymers (POPs) can not only exhibit high specific surface area and pore volume, but also tunable pore size distribution. Herein, copolymers of 2-hydroxyethylmethylacrylate (HEMA) and divinylbenzene (DVB) with specific pore structure were synthesized via a dispersion polymerization strategy, and then immobilized metallocene catalysts with well-defined pore structure were obtained on the produced POP supports. The nitrogen sorption and Gel permeation chromatography (GPC) results demonstrate that the pore structure of the immobilized metallocene catalyst is highly dependent on the pore structure of the POPs, and the pore structure of metallocene catalysts or the POPs has a significant influence on the molecular chain growth of the produced polyethylene. By tuning the distribution of the active species scattered in the micro- and the narrow meso-pore range (roughly ≤4 nm), the chain growth of the polyolefin can be tailored effectively during the polymerization process, although differential scanning calorimetry (DSC) and temperature rising elution fractionation (TREF) results show that the chemical composition distributions (CCDs) of produced PE from the POPs-supported metallocene catalysts are not determined by polymerization activity or molecule chain length, but mainly by the active site species scattered in the supported catalysts. Scanning electron micrograph (SEM) shows that the produced polyethylene has highly porous fabric which consists of nanofiber and spherical beads of micron dimension.

  10. Metallocenes--The First 25 Years

    ERIC Educational Resources Information Center

    Hunt, C. B.

    1977-01-01

    This article reviews the discovery of the first of the metallocenes and some of the developments which have taken place in the 25 years following. Applications to topics such as the solution of the polyphenylchromium problem and Alkene polymerisation, are discussed. Ferrocene is studied in detail. (MA)

  11. Metallocene Catalytic Insertion Polymerization of 1-Silene to Polycarbosilanes

    NASA Astrophysics Data System (ADS)

    Tian, Yuelong; Ge, Min; Zhang, Weigang; Lv, Xiaoxu; Yu, Shouquan

    2015-11-01

    Metallocene of zirconium were used as a catalyst for an insertion polymerization of 1-methylsilene directly into pre-ceramic precursor polyzirconocenecarbosilane (PZCS) during dechlorination of dichlorodimethylesilane by sodium, which exhibits high catalytic effectiveness with the maximum conversion ratio of polycarbosilane up to 91%. The average molecular weights of polymers synthesized are less than 1400, all with very narrow polymolecularities. The mechanism of catalytic polymerization was assumed to be similar to a coordination insertion polymerization of 1-olefins by metallocenes. The obtained PZCS show high ceramic yields with formation of composite ceramics of ZrC-SiC, which are novel polymeric precursors of ultra-high temperature ceramic (UHTC) fiber and composite.

  12. Metallocene Catalytic Insertion Polymerization of 1-Silene to Polycarbosilanes.

    PubMed

    Tian, Yuelong; Ge, Min; Zhang, Weigang; Lv, Xiaoxu; Yu, Shouquan

    2015-11-06

    Metallocene of zirconium were used as a catalyst for an insertion polymerization of 1-methylsilene directly into pre-ceramic precursor polyzirconocenecarbosilane (PZCS) during dechlorination of dichlorodimethylesilane by sodium, which exhibits high catalytic effectiveness with the maximum conversion ratio of polycarbosilane up to 91%. The average molecular weights of polymers synthesized are less than 1400, all with very narrow polymolecularities. The mechanism of catalytic polymerization was assumed to be similar to a coordination insertion polymerization of 1-olefins by metallocenes. The obtained PZCS show high ceramic yields with formation of composite ceramics of ZrC-SiC, which are novel polymeric precursors of ultra-high temperature ceramic (UHTC) fiber and composite.

  13. On the Discovery, Biological Effects, and Use of Cisplatin and Metallocenes in Anticancer Chemotherapy

    PubMed Central

    Gómez-Ruiz, Santiago; Maksimović-Ivanić, Danijela; Mijatović, Sanja; Kaluđerović, Goran N.

    2012-01-01

    The purpose of this paper is to summarize mode of action of cisplatin on the tumor cells, a brief outlook on the metallocene compounds as antitumor drugs as well as the future tendencies for the use of the latter in anticancer chemotherapy. Molecular mechanisms of cisplatin interaction with DNA, DNA repair mechanisms, and cellular proteins are discussed. Molecular background of the sensitivity and resistance to cisplatin, as well as its influence on the efficacy of the antitumor immune response was evaluated. Furthermore, herein are summarized some metallocenes (titanocene, vanadocene, molybdocene, ferrocene, and zirconocene) with high antitumor activity. PMID:22844263

  14. Preparation, characterization, and catalytic activity of zirconocene bridged on surface of silica gel

    NASA Astrophysics Data System (ADS)

    El Majdoub, Lotfia; Shi, Yasai; Yuan, Yuan; Zhou, Annan; Abutartour, Abubaker; Xu, Qinghong

    2015-10-01

    Zirconocene catalyst supported on silica gel was prepared for olefin polymerization by surface modification of calcined silica with SiCl4, and the reaction between the modified silica and cyclopentadienyl sodium and ZrCl4. The catalyst was characterized by using Fourier-transform infrared (FT-IR) spectrometer, thermogravimetric (TG), and differential scanning calorimetric (DSC) analytic spectrometer. It was found that the metallocene structure could be formed and connected on silica surface by chemical bond. Initial catalytic tests showed that the supported metallocene was catalytically active (methylaluminoxane as a cocatalyst), producing polymer with higher molecular weight than the metallocene just immobilized on the surface of silica gel.

  15. Rhodium-catalyzed enantioselective intramolecular C-H silylation for the syntheses of planar-chiral metallocene siloles.

    PubMed

    Zhang, Qing-Wei; An, Kun; Liu, Li-Chuan; Yue, Yuan; He, Wei

    2015-06-01

    Reported herein is the rhodium-catalyzed enantioselective C-H bond silylation of the cyclopentadiene rings in Fe and Ru metallocenes. Thus, in the presence of (S)-TMS-Segphos, the reactions took place under very mild conditions to afford metallocene-fused siloles in good to excellent yields and with ee values of up to 97%. During this study it was observed that the steric hindrance of chiral ligands had a profound influence on the reactivity and enantioselectivity of the reaction, and might hold the key to accomplishing conventionally challenging asymmetric C-H silylations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. 40 CFR 61.62 - Emission standard for ethylene dichloride plants.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission... dichloride purification. The concentration of vinyl chloride in each exhaust gas stream from any equipment used in ethylene dichloride purification is not to exceed 10 ppm (average for 3-hour period), except as...

  17. 40 CFR 61.62 - Emission standard for ethylene dichloride plants.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission... dichloride purification. The concentration of vinyl chloride in each exhaust gas stream from any equipment used in ethylene dichloride purification is not to exceed 10 ppm (average for 3-hour period), except as...

  18. 40 CFR 61.62 - Emission standard for ethylene dichloride plants.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission... dichloride purification. The concentration of vinyl chloride in each exhaust gas stream from any equipment used in ethylene dichloride purification is not to exceed 10 ppm (average for 3-hour period), except as...

  19. 40 CFR 61.62 - Emission standard for ethylene dichloride plants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission... dichloride purification. The concentration of vinyl chloride in each exhaust gas stream from any equipment used in ethylene dichloride purification is not to exceed 10 ppm (average for 3-hour period), except as...

  20. 40 CFR 61.62 - Emission standard for ethylene dichloride plants.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard for ethylene... Standard for Vinyl Chloride § 61.62 Emission standard for ethylene dichloride plants. (a) Ethylene... used in ethylene dichloride purification is not to exceed 10 ppm (average for 3-hour period), except as...

  1. Human ovarian cancer xenografts in nude mice: chemotherapy trials with paclitaxel, cisplatin, vinorelbine and titanocene dichloride.

    PubMed

    Villena-Heinsen, C; Friedrich, M; Ertan, A K; Farnhammer, C; Schmidt, W

    1998-07-01

    The new cytostatics titanocene dichloride and vinorelbine were compared to cisplatin and paclitaxel using a human ovarian cancer xenografts model. Biopsy material from a native human ovarian carcinoma was expanded and transplanted into 96 nude mice. The animals were divided into six treatment groups: cisplatin 3 x 4 mg/kg, paclitaxel 5 x 26 mg/kg, vinorelbine 1 x 20 mg/kg, titanocene dichloride 3 x 30 mg/kg, titanocene dichloride 3 x 40 mg/kg and a control group treated with 0.9% saline. Each experiment was repeated with eight mice in each treatment group. Treatment groups were evaluated in terms of average daily increase in tumor volume and average daily body weight increase of nude mice based on slopes of least-square regressions performed on individual animals. The slope factors alpha and beta of the body weight (alpha) and tumor volume changes (beta) within each group during the course of an experiment were calculated. Both a statistically significant decrease (p<0.05) in the body weight of the experimental animals (cisplatin: alpha = -0.5163, vinorelbine: alpha = -0.6598, paclitaxel: alpha = -0.6746, titanocene dichloride 3 x 30 mg/kg: alpha = -0.6259, titanocene dichloride 3 x 40 mg/kg: alpha = -0.7758) and a significant reduction (p<0.05) of the increase in tumor volume (cisplatin: beta = 12.049, vinorelbine: beta = 0.504, paclitaxel: beta = -1.636, titanocene dichloride 3 x 30 mg/kg: beta = 6.212, titanocene dichloride 3 x 40 mg/kg: beta= -0.685) was shown in all treated groups compared to the control group (alpha = -0.1398; beta = 23.056). No significant weight changes were observed between the individually treated groups. A statistically significant reduction of the tumor growth occured under paclitaxel (beta = -1.636), vinorelbine (beta = 0.504) and titanocene dichloride medication 3 x 40 mg/kg (beta = -0.685), as compared to the group treated with cisplatin (beta = 12.049). We found titanocene dichloride to be as effective as paclitaxel and more effective than cisplatin. Vinorelbine seems to be a very effective antineoplastic agent exhibiting a significant higher cytostatic effect than cisplatin. Both titanocene dichloride and vinorelbine provide new therapeutic options in women with ovarian carcinoma not responding to standard chemotherapy.

  2. Effects of vinorelbine and titanocene dichloride on human tumour xenografts in nude mice.

    PubMed

    Friedrich, M; Villena-Heinsen, C; Farnhammer, C; Schmidt, W

    1998-01-01

    In this study, the new antineoplastic agents titanocene dichloride and vinorelbine are compared to cisplatin and paclitaxel using a human ovarian cancer xenograft model. Biopsy material from one native human ovarian carcinoma was expanded and transplanted into 48 nude mice. The animals were divided into six treatment groups: cisplatin 3x4 mg/kg, paclitaxel 5x26 mg/kg, vinorelbine 1x20 mg/kg, titanocene dichloride 3x30 mg/kg, titanocene dichloride 3x40 mg/kg and a control group treated with 0.9% saline. Treatment groups were evaluated in terms of average daily increase in tumour volume and average daily body weight increase of the nude mice based on slopes of least square regressions performed on individual animals. The slope factors alpha and beta of the body weight (alpha) and tumour volume changes (beta) within each group were calculated. A statistically significant decrease (p<0.05) in body weight of the experimental animals was shown in groups treated with paclitaxel (alpha = -0.6878) and titanocene dichloride 3x40 mg/kg (alpha = -0.7194) compared to the control group which was treated with 0.9% saline (alpha = -0.2643). Significant body weight changes were not observed in the comparison of the remaining treated groups (cisplatin: alpha = -0.4552, vinorelbine: alpha = -0.5606, titanocene dichloride 3x30 mg/kg: alpha = -0.6173 to the control group. A significant reduction (p<0.05) of the increase tumour volume (vinorelbine: beta = 5.260, paclitaxel: beta = 0.478, titanocene dichloride 3x30 mg/kg: beta = 10.283, titanocene dichloride 3x40 mg/kg: beta = 5.768) was shown in treated groups except for cisplatin (beta = 18.722) compared to the tumour bearing control group (beta = 30.136). A statistically significant reduction of the increase in tumour volume occurred under paclitaxel medication compared to the group treated with cisplatin. We found titanocene dichloride to be effective as vinorelbine and more effective than cisplatin. Vinorelbine seems to be a very effective antineoplastic agent with a significantly higher cytostatic effect than cisplatin. Both titanocene dichloride and vinorelbine provide new therapeutic options in women with ovarian carcinoma not responding to standard chemotherapies.

  3. Metallocene catalyst containing bulky organic group

    DOEpatents

    Marks, T.J.; Ja, L.; Yang, X.

    1996-03-26

    An ionic metallocene catalyst for olefin polymerization which comprises: (1) a cyclopentadienyl-type ligand, a Group IVB transition metal, and alkyl, aryl, or hydride substituents, as a cation, and (2) a weakly coordinating anion comprising boron substituted with halogenated, such as tetrafluoro-aryl substituents preferably containing silylalkyl substitution, such as para-silyl t-butyldimethyl.

  4. Synthesis and Characterization of Cerium(IV) Metallocenes

    DOE PAGES

    Sutton, Andrew; Clark, David Lewis; Scott, Brian Lindley; ...

    2015-12-11

    In this study, by applying a salt metathesis approach between Ce(OtBu 3) 2(NO 3) 2(THF) 2 and the potassium salts of mono- and ditrimethylsilyl substituted cyclopentadienes, we were able to isolate two new Ce(IV) metallocenes, including to the best of our knowledge, the first structurally characterized bis-cyclopentadiene Ce(IV) compound.

  5. Metallocene catalyst containing bulky organic group

    DOEpatents

    Marks, Tobin J.; Ja, Li; Yang, Xinmin

    1996-03-26

    An ionic metallocene catalyst for olefin polymerization which comprises: (1) a cyclopentadienyl-type ligand, a Group IVB transition metal, and alkyl, aryl, or hydride substituents, as a cation, and (2) a weakly coordinating anion comprising boron substituted with halogenated, such as tetra fluoro, aryl substituents preferably containing silylalkyl substitution, such as para-silyl t-butyldimethyl.

  6. 40 CFR 61.65 - Emission standard for ethylene dichloride, vinyl chloride and polyvinyl chloride plants.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission standard for ethylene... AIR POLLUTANTS National Emission Standard for Vinyl Chloride § 61.65 Emission standard for ethylene dichloride, vinyl chloride and polyvinyl chloride plants. An owner or operator of an ethylene dichloride...

  7. Specific Interactions of Antitumor Metallocenes with Deoxydinucleoside Monophosphates

    NASA Astrophysics Data System (ADS)

    Eberle, Rahel P.; Hari, Yvonne; Schürch, Stefan

    2017-09-01

    Bent metallocenes Cp2MCl2 (M = Ti, V, Nb, Mo) are known to exhibit cytotoxic activity against a variety of cancer types. Though the mechanism of action is not fully understood yet, the accumulation of the metal ions in the nucleus points towards DNA as one of the primary targets. A set of eight deoxydinucleoside monophosphates was used to study the adduct yields with metallocenes and cisplatin. The binding affinities are reflected by the relative intensities of the adducts and were found to follow the order of Pt > V > Ti > Mo (no adducts were detected with Nb). High-resolution tandem mass spectrometry was applied to locate the binding patterns in the deoxydinucleoside monophosphates. Whereas cisplatin binds to the soft nitrogen atoms in the purine nucleobases, the metallocenes additionally interact with the hard phosphate oxygen, which is in good agreement with the hard and soft (Lewis) acids and bases (HSAB) concept. However, the binding specificities were found to be unique for each metallocene. The hard Lewis acids titanium and vanadium predominantly bind to the deprotonated phosphate oxygen, whereas molybdenum, an intermediate Lewis acid, preferentially interacts with the nucleobases. Nucleobases comprise alternative binding sites for titanium and vanadium, presumably oxygen atoms for the first and nitrogen atoms for the latter. In summary, the intrinsic binding behavior of the different metallodrugs is reflected by the gas-phase dissociation of the adducts. Consequently, MS/MS can provide insights into therapeutically relevant interactions between metallodrugs and their cellular targets. [Figure not available: see fulltext.

  8. Genetic toxicology assessment of HI-6 dichloride

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

    Putman, D.; San, R.H.; Bigger, C.A.

    1996-08-01

    The oxime HI-6 dichloride (1-(2 hydroxyiminomethyl- 1-pyridino)-3- (4-carbamoyl-1- pyridino)-2-oxapropane dichloride monohydrate) has shown to be a potent reactivator of cholinesterase activity and may have efficacy for the treatment of organo-phosphate intoxication (SIPRI, 1976; Schenk et al.; Arch Toxicol 36:71-81, 1976). As part of a pre-clinical safety assessment program, the genetic toxicology of HI-6 dichloride was evaluated in a series of assays designed to measure induction of gene mutations and chromosomal aberrations. HI-6 dichloride gave negative responses in the Salmonella mutagenicity assay and in the CHO/HGPRT gene mutation assay. Dose-dependent increases in the frequency of chromosomal aberrations when HI-6 dichloride wasmore » tested in cultured CHO cells and in cultured human peripheral blood lymphocytes. The mouse lymphoma gene mutation assay, reputed to measure both gene mutations and chromosomal deletions, was negative in the absence of metabolic activation. Depending on the criteria employed, a negative or equivocal response was seen in the presence of rat liver-derived S-9 mix. An in vivo rat bone marrow metaphase assay performed to further investigate the in vitro clastogenic responses was negative. The results from these studies indicate that HI-6 dichloride does not induce gene mutations in vitro; however, it is clastogenic in vitro but does not appear to be clastogenic in vivo.« less

  9. Quantum transport of the single metallocene molecule

    NASA Astrophysics Data System (ADS)

    Yu, Jing-Xin; Chang, Jing; Wei, Rong-Kai; Liu, Xiu-Ying; Li, Xiao-Dong

    2016-10-01

    The Quantum transport of three single metallocene molecule is investigated by performing theoretical calculations using the non-equilibrium Green's function method combined with density functional theory. We find that the three metallocen molecules structure become stretched along the transport direction, the distance between two Cp rings longer than the other theory and experiment results. The lager conductance is found in nickelocene molecule, the main transmission channel is the electron coupling between molecule and the electrodes is through the Ni dxz and dyz orbitals and the s, dxz, dyz of gold. This is also confirmed by the highest occupied molecular orbital resonance at Fermi level. In addition, negative differential resistance effect is found in the ferrocene, cobaltocene molecules, this is also closely related with the evolution of the transmission spectrum under applied bias.

  10. Activation of C-H bonds by rare-earth metallocene-butyl complexes.

    PubMed

    Grindell, Richard; Day, Benjamin M; Guo, Fu-Sheng; Pugh, Thomas; Layfield, Richard A

    2017-09-05

    The stable metallocene-butyl complexes [(Cp Me ) 2 M( n Bu)] 2 (M = Y, Dy) were synthesized and their reactivity towards to ferrocene and bulky N-heterocyclic carbenes investigated. Selective mono-deprotonation of ferrocene and a benzylic methyl group of IMes were observed, whereas a control reaction of (Cp Me ) 3 M with IMes resulted in a normal-to-abnormal NHC rearrangement.

  11. Efficient palladium-catalyzed asymmetric allylic alkylation of ketones and aldehydes.

    PubMed

    Zhao, Xiaohu; Liu, Delong; Xie, Fang; Liu, Yangang; Zhang, Wanbin

    2011-03-21

    Palladium-catalyzed asymmetric allylic alkylation of ketones, via enamines generated in situ as nucleophiles, were carried out smoothly with chiral metallocene-based P,N-ligands. Under the same conditions, however, reactions of aldehydes could hardly be observed. Subsequently, this obstacle was resolved by using chiral metallocene-based P,P-ligands. Both ketones and aldehydes afforded excellent enantioselectivities with up to 98% ee and 94% ee, respectively.

  12. Paraquat Dichloride

    EPA Pesticide Factsheets

    Paraquat dichloride, commonly referred to as “paraquat,” is one of the most widely used herbicides registered in the United States. Paraquat is also often referred to as Gramoxone (a popular end-use product).

  13. 21 CFR 173.230 - Ethylene dichloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 30 parts per million is established for ethylene dichloride in spice oleoresins when present therein as a residue from the extraction of spice; Provided, however, That if residues of other chlorinated...

  14. 40 CFR 98.240 - Definition of the source category.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... acrylonitrile, carbon black, ethylene, ethylene dichloride, ethylene oxide, or methanol, except as specified in... independently of an oxychlorination process to produce ethylene dichloride is not part of the petrochemical...

  15. EPR study of free radical in gamma-irradiated bis(cyclopentadienyl)zirconium dichloride single crystal

    NASA Astrophysics Data System (ADS)

    Caliskan, Betul; Caliskan, Ali Cengiz

    2017-06-01

    Bis(cyclopentadienyl)zirconium dichloride (BCZD; zirconocene dichloride) single crystals were exposed to 60Co-γ irradiation at room temperature. The irradiated single crystals were investigated between 125 and 470 K by electron paramagnetic resonance spectroscopy. The spectra of the crystals were found to be temperature independent. The paramagnetic center was attributed to the cyclopentadienyl radical. The g values of the radiation damage center observed in BCZD single crystal and the hyperfine structure constants of the free electron with nearby protons were obtained.

  16. 78 FR 8513 - Product Cancellation Order for Certain Pesticide Registrations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ...) Granular Concentrate. ethylene(dimethylimino)ethylene dichloride). 004787-00036 Glyfos Au Herbicide...-dimethyl, chloride. 045309-00010 Aqua Clear Algae Preventative.... Poly(oxyethylene(dimethylimino) ethylene(dimethylimino)ethylene dichloride). 045309-00011 Spa Clear Non-Foaming Algaecide.. Poly(oxyethylene...

  17. 40 CFR 61.61 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polymerization process which initiates from free radical catalyst sites and is sold undried. (i) Bulk resin means... as follows: (a) Ethylene dichloride plant includes any plant which produces ethylene dichloride by reaction of oxygen and hydrogen chloride with ethylene. (b) Vinyl chloride plant includes any plant which...

  18. 40 CFR 61.61 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polymerization process which initiates from free radical catalyst sites and is sold undried. (i) Bulk resin means... as follows: (a) Ethylene dichloride plant includes any plant which produces ethylene dichloride by reaction of oxygen and hydrogen chloride with ethylene. (b) Vinyl chloride plant includes any plant which...

  19. Synthesis, characterization and photophysical properties of ferrocenyl and mixed sandwich cobaltocenyl ester linked meso-triaryl corrole dyads

    NASA Astrophysics Data System (ADS)

    Achary, B. Shivaprasad; Ramya, A. R.; Trivedi, Rajiv; Bangal, P. R.; Giribabu, L.

    We report here the design and synthesis of corrole-metallocene dyads consisting of a metallocene (either ferrocene (Dyad 1) or mixed sandwich η5-[C5H4(COOH)]Co(η4-C4Ph4) (Dyad 2)) connected via an ester linkage at meso phenyl position. Both the dyads were characterized by 1H NMR, MALDI-TOF, UV-visible, fluorescence spectroscopies (steady-state, picosecond time-resolved), femtosecond transient absorption spectroscopy (fs-TA) and electrochemical methods. The absorption spectra of these dyads showed slight broadening and splitting of the Soret band that indicates a weak ground state interaction between the corrole macrocycle and metallocene part of the present donor-acceptor (D-A) system. However, in both the dyad systems, fluorescence emission of the corrole was quenched in polar solvents as compared to its parent compound 10-(4-hydroxyphenyl)-5,15-bis-(pentafluorophenyl ) corrole (Ph-Corr). The quenching was more pronounced in ferrocene derivatives than in cobaltocenyl derivatives. Transient absorption studies confirm the absence of photoinduced electron transfer from metallocene to correl for these dyad systems and the quenching of singlet state of corrole is found to enhance intersystem crossing due to heavy atom effect. Corrole-ferrocene and corrole-mixed sandwich η5-[C5H4(COOH)]Co(η4-C4Ph4) dyads have been designed, synthesized and characterized by various spectroscopic techniques. Emission intensitiy of both dyads were quenched in polar solvents whereas transient absorption studies indicates that the quenching coule be due to the heavy atom effect.

  20. Biological Interaction of Molybdenocene Dichloride with Bovine Serum Albumin Using Fluorescence Spectroscopy

    ERIC Educational Resources Information Center

    Domínguez, Moralba; Cortes-Figueroa, Jose´ E.; Meléndez, Enrique

    2018-01-01

    Bioinorganic topics are ubiquitous in the inorganic chemistry curriculum; however, experiments to enhance understanding of related topics are scarce. In this proposed laboratory, upper undergraduate students assess the biological interaction of molybdenocene dichloride (Cp2MoCl2) with bovine serum albumin (BSA) by fluorescence spectroscopy.…

  1. The Influence of Ziegler-Natta and Metallocene Catalysts on Polyolefin Structure, Properties, and Processing Ability

    PubMed Central

    Shamiri, Ahmad; Chakrabarti, Mohammed H.; Jahan, Shah; Hussain, Mohd Azlan; Kaminsky, Walter; Aravind, Purushothaman V.; Yehye, Wageeh A.

    2014-01-01

    50 years ago, Karl Ziegler and Giulio Natta were awarded the Nobel Prize for their discovery of the catalytic polymerization of ethylene and propylene using titanium compounds and aluminum-alkyls as co-catalysts. Polyolefins have grown to become one of the biggest of all produced polymers. New metallocene/methylaluminoxane (MAO) catalysts open the possibility to synthesize polymers with highly defined microstructure, tacticity, and steroregularity, as well as long-chain branched, or blocky copolymers with excellent properties. This improvement in polymerization is possible due to the single active sites available on the metallocene catalysts in contrast to their traditional counterparts. Moreover, these catalysts, half titanocenes/MAO, zirconocenes, and other single site catalysts can control various important parameters, such as co-monomer distribution, molecular weight, molecular weight distribution, molecular architecture, stereo-specificity, degree of linearity, and branching of the polymer. However, in most cases research in this area has reduced academia as olefin polymerization has seen significant advancements in the industries. Therefore, this paper aims to further motivate interest in polyolefin research in academia by highlighting promising and open areas for the future. PMID:28788120

  2. Advanced rechargeable sodium batteries with novel cathodes

    NASA Technical Reports Server (NTRS)

    Distefano, S.; Ratnakumar, B. V.; Bankston, C. P.

    1989-01-01

    Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium-sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 Wh/kg theoretical). Energy densities in excess of 180 Wh/kg were realized in practical batteries. Other technological advantages include its chemical simplicity, absence of self-discharge, and long cycle life possibility. More recently, other high temperature sodium batteries have come into the spotlight. These systems can be described as follow: Na/Beta Double Prime-Al2O3/NaAlCl4/Metal Dichloride Sodium/metal dichloride systems are colloquially known as the zebra system and are currently being developed for traction and load leveling applications. The sodium-metal dichloride systems appear to offer many of the same advantages of the Na/S system, especially in terms of energy density and chemical simplicity. The metal dichloride systems offer increased safety and good resistance to overcharge and operate over a wide range of temperatures from 150 to 400 C with less corrosion problems.

  3. The use of functionalized zirconocenes as precursors to silica-supported zirconocene olefin polymerization catalysts

    NASA Astrophysics Data System (ADS)

    Cheng, Xu

    2001-07-01

    Me3Si substituents adjacent to Cp2MCl2 (M = Ti, Zr, Hf) are converted to BrMe2Si groups using BBr 3. The high reactivity of the Si-Br bonds toward nucleophiles such as water suggested that these substituents could react with hydroxylated silica surfaces, immobilizing the metallocenes. This dissertation concerns the syntheses of electrophile-functionalized zirconocene dihalide complexes and their use as precursors to silica-supported metallocene olefin polymerization catalysts. First we extended the metallocene "functionalization" chemistry to obtain substituents bearing more than one electrophilic bond. (Me3Sn) 2C5H4 combined with CpZrCl3 in toluene to afford (eta5-Me3Sn-C5H4)CpZrCl 2 (A). Reactions of A with electrophiles (E-X = Cl2B-Cl, I-Cl, and I-I) afforded (eta5-XMe 2Sn-C5H4)CpZrCl2 (and E-Me) cleanly. The reaction of A with BBr3 afforded either (eta5-BrMe2Sn-C5H4)CpZrBr2 (25 °C, 10 min) or (eta5-Br2MeSn-C5H 4)CpZrBr2 (25 °C, 15 h). Ph2MeSi-C5H 4Li combined with ZrCl4•2THF to afford (eta 5-Ph2MeSi-C5H4)2ZrCl 2 (B). The reaction of B with BCl3 led to incomplete cleavage of the Ph-Si bonds, however treatment of B with BBr3 afforded (eta5-Br2MeSi-C 5H4)2ZrBr2 (C) efficiently. X-ray crystal structures of (eta5-ClMe2Sn-C 5H4)CpZrCl2•1/2toluene, (eta 5-Br2MeSn-C5H4)CpZrBr2•THF, B, and C were obtained. Metallocene C reacts with water to afford an oligosiloxane-supported zirconocene dibromide. Spectroscopic characterization suggested a stereoregular structure in which the metallocene units have meso symmetry. The oligomeric substance showed high activity for homogeneous ethylene polymerization. Supported metallocene olefin polymerization catalysts were prepared by combining a functionalized metallocene precursor (Cp2ZrBr 2 bearing either BrMe2Si or Br2MeSi groups) and partially dehydroxylated silica. The activities of the immobilized zirconocene catalysts decreased and the stabilities increased with increasing number of tethers. The immobilized catalyst prepared from (eta5-Br 2MeSi-C5H4)2ZrBr2, which is assumed to form two "double-tethers" to silica, was significantly more active than the catalyst prepared from [eta5-1,3-(BrMe 2Si)2C5H3]2ZrBr2, which is assumed to form four "single-tethers" to silica. Catalyst leaching was observed in all the immobilized zirconocene catalysts. Finally we report model studies on the stability of the Si-O-Si bonds toward methylaluminoxane (MAO). The reaction of (eta5-BrMe 2Si-C5H4)CpZrBr2 with tBuMe 2SiOH results in the formation of Si-O-Si bonds; addition of NEt 3 results in further reaction to afford Si-O-Zr bonds. The reaction of Me3Si-O-SiMe3 with MAO showed that Si-O-Si bonds can be cleaved under the conditions of our polymerization reactions.

  4. Assessment of the Mutagenic Potential of Carbon Disulfide, Carbon Tetrachloride, Dichloromethane, Ethylene Dichloride, and Methyl Bromide: A Comparative Analysis in Relation to Ethylene Dibromide

    EPA Science Inventory

    The document provides an evaluation of the mutagenic potential of five alternative fumigants to ethylene dibromide(EDB). These include carbon disulfide(CS2), carbon tetrachloride(CCl4), dichloromethane(DCM), ethylene dichloride(EDC), and methyl bromide (MB). Of the five proposed ...

  5. Correction: Reactions of metallodrugs with proteins: selective binding of phosphane-based platinum(ii) dichlorides to horse heart cytochrome c probed by ESI MS coupled to enzymatic cleavage.

    PubMed

    Mügge, Carolin; Michelucci, Elena; Boscaro, Francesca; Gabbiani, Chiara; Messori, Luigi; Weigand, Wolfgang

    2018-05-23

    Correction for 'Reactions of metallodrugs with proteins: selective binding of phosphane-based platinum(ii) dichlorides to horse heart cytochrome c probed by ESI MS coupled to enzymatic cleavage' by Carolin Mügge et al., Metallomics, 2011, 3, 987-990.

  6. Vibrational overtone spectra of metallocenes: effect of the coordinating metal on the CH bond lengths

    NASA Astrophysics Data System (ADS)

    Billinghurst, Brant E.; Gough, Kathleen M.

    2003-03-01

    The first through third overtone spectra of ferrocene, ruthenocene, nickelocene, cobaltocene, dicyclopentadienyl magnesium and sodium cyclopentadienyl are examined with particular attention to the CH stretching of the cyclopentadienyl. Using semi-empirical correlations between CH bond length and CH stretching frequencies in each overtone region, we have determined that the type of metal atom within a metallocene complex has little effect on the CH bond length in the cyclopentadienyl. The only exception is cobaltocene where there is evidence that the Jahn-Teller effect results in several different CH bond lengths. Evidence that bis(cyclopentadienyl) magnesium is not ionic has been observed.

  7. Hyaluronidase: its effects on HI-6 dichloride and dimethanesulphonate pharmacokinetic profile in pigs.

    PubMed

    Karasova, Jana Zdarova; Pavlik, Michal; Chladek, Jaroslav; Jun, Daniel; Kuca, Kamil

    2013-07-04

    Pigs were administered intramuscularly molar equivalents of HI-6 salts (HI-6 dichloride 10.71 mg/kg and HI-6 DMS 13.59 mg/kg) either with or without hyaluronidase (60 U/kg). Hyaluronidase is supposed to increase tissue permeability and diminishes discomfort caused by the intramuscular injection. Doses of HI-6 salts corresponded with standard HI-6 dichloride dose in one autoinjector (500 mg) and were recalculated for 1 kg of body weight. According to the results, both HI-6 salts applied in combination with hyaluronidase had increased tissue absorption and improved pharmacokinetic profile. The Cmax was significantly higher in case of HI-6 DMS plus hyaluronidase (29.6 ± 2.98 μg/ml) administration increase compared to HI-6 DMS (23.8 ± 3.04 μg/ml) and HI-6 dichloride (19.0 ± 0.93 μg/ml); both without hyaluronidase. Bioavailability calculated as AUCtotal (HI-6 DMS with hyaluronidase, 4,119 ± 647 min μg/ml) was also significantly higher compared to HI-6 DMS (2,259 ± 329 min μg/ml) and HI-6 dichloride (1,969 ± 254 min μg/ml); both without hyaluronidase. The results suggest that administration of HI-6 salt with higher solubility is the first step in the improvement of application strategy, but use some substances with spreading effect (hyaluronidase) may also leads to better absorption and better bioavailability. Improved bioavailability could to go hand in hand with increased effectiveness of therapy without the need of multiple autoinjector applications. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Development of the 2007 Chemical Decontaminant Source Document

    DTIC Science & Technology

    2009-03-01

    Chemical Agent Simulant Specific DEM diethyl malonate MeS methyl salicylate PEG200 Polyethylene glycol 200 TEP triethyl phosphate Group 6...simulants • H-agent simulants o Methyl salicylate (MeS) o Chloroethyl phenyl sulfide (CEPS) o Chloroethyl ethyl sulfide (CEES) • VX simulants... Methyl bromide Ethyl phosphonothioic dichloride Sulfur dioxide Methyl chloroformate Ethyl phosphonic dichloride Sulfuric acid Methyl chlorosilane

  9. Catalytic activity during copolymerization of ethylene and 1-hexene via mixed TiO2/SiO2-supported MAO with rac-Et[Ind]2ZrCl2 metallocene catalyst.

    PubMed

    Jongsomjit, Bunjerd; Ngamposri, Sutti; Praserthdam, Piyasan

    2005-07-14

    Activities during ethylene/1-hexene copolymerization were found to increase using the mixed titania/silica-supported MAO with rac-Et[Ind]2ZrCl2 metallocene catalyst. Energy Dispersive X-ray spectorcopy (EDX) indicated that the titania was apparently located on the outer surface of silica and acted as a spacer to anchor MAO to the silica surface. IR spectra revealed the Si-O-Ti stretching at 980 cm(-1) with low content of titania. The presence of anchored titania resulted in less steric hindrance and less interaction due to supporting effect.

  10. Novel Potent Metallocenes against Liver Stage Malaria

    PubMed Central

    Matos, Joana; da Cruz, Filipa P.; Cabrita, Élia; Gut, Jiri; Nogueira, Fátima; do Rosário, Virgílio E.; Moreira, Rui; Rosenthal, Philip J.; Prudêncio, Miguel

    2012-01-01

    Novel conjugates of the antimalarial drug primaquine (compound 1) with ferrocene, named primacenes, have been synthesized and screened for their activities against blood stage and liver stage malaria in vitro and host-vector transmission in vivo. Both transmission-blocking and blood-schizontocidal activities of the parent drug were conserved only in primacenes bearing a basic aliphatic amine group. Liver stage activity did not require this structural feature, and all metallocenes tested were comparable to or better than primaquine in this regard. Remarkably, the replacement of primaquine's aliphatic chain by hexylferrocene, as in compound 7, led to a ∼45-fold-higher level activity against liver stage parasitemia than that of primaquine. PMID:22155838

  11. Synthesis and characterization of bis-thiourea having amino acid derivatives

    NASA Astrophysics Data System (ADS)

    Fakhar, Imran; Yamin, Bohari M.; Hasbullah, Siti Aishah

    2016-11-01

    In this article four new symmetric bis-thiourea derivatives having amino acid linkers were reported with good yield. Isophthaloyl dichloride was used as spacer and L-alanine, L-aspartic acid, L-phenylalanine and L-glutamic acid were used as linkers. Bis-thiourea derivatives were prepared from relatively stable isophthaloyl isothiocyanate intermediate. Newly synthesized bis-thiourea derivatives were characterized by FTIR, H-NMR, 13C-NMR and CHNS-O elemental analysis techniques. Characterization data was in good agreement with the expected derivatives, hence confirmed the synthesis of four new derivatives of bis-thiourea having amino acids.

  12. Morphological, rheological and mechanical characterization of polypropylene nanocomposite blends.

    PubMed

    Rosales, C; Contreras, V; Matos, M; Perera, R; Villarreal, N; García-López, D; Pastor, J M

    2008-04-01

    In the present work, the effectiveness of styrene/ethylene-butylene/styrene rubbers grafted with maleic anhydride (MA) and a metallocene polyethylene (mPE) as toughening materials in binary and ternary blends with polypropylene and its nanocomposite as continuous phases was evaluated in terms of transmission electron microscopy (TEM), scanning electron microscopy (SEM), oscillatory shear flow and dynamic mechanical thermal analysis (DMA). The flexural modulus and heat distortion temperature values were determined as well. A metallocene polyethylene and a polyamide-6 were used as dispersed phases in these binary and ternary blends produced via melt blending in a corotating twin-screw extruder. Results showed that the compatibilized blends prepared without clay are tougher than those prepared with the nanocomposite of PP as the matrix phase and no significant changes in shear viscosity, melt elasticity, flexural or storage moduli and heat distortion temperature values were observed between them. However, the binary blend with a nanocomposite of PP as matrix and metallocene polyethylene phase exhibited better toughness, lower shear viscosity, flexural modulus, and heat distortion temperature values than that prepared with polyamide-6 as dispersed phase. These results are related to the degree of clay dispersion in the PP and to the type of morphology developed in the different blends.

  13. Molecular geometry of vanadium dichloride and vanadium trichloride: a gas-phase electron diffraction and computational study.

    PubMed

    Varga, Zoltán; Vest, Brian; Schwerdtfeger, Peter; Hargittai, Magdolna

    2010-03-15

    The molecular geometries of VCl2 and VCl3 have been determined by computations and gas-phase electron diffraction (ED). The ED study is a reinvestigation of the previously published analysis for VCl2. The structure of the vanadium dichloride dimer has also been calculated. According to our joint ED and computational study, the evaporation of a solid sample of VCl2 resulted in about 66% vanadium trichloride and 34% vanadium dichloride in the vapor. Vanadium dichloride is unambiguously linear in its 4Sigma(g)+ ground electronic state. For VCl3, all computations yielded a Jahn-Teller-distorted ground-state structure of C(2v) symmetry. However, it lies merely less than 3 kJ/mol lower than the 3E'' state (D(3h) symmetry). Due to the dynamic nature of the Jahn-Teller effect in this case, rigorous distinction cannot be made between the planar models of either D(3h) symmetry or C(2v) symmetry for the equilibrium structure of VCl3. Furthermore, the presence of several low-lying excited electronic states of VCl3 is expected in the high-temperature vapor. To our knowledge, this is the first experimental and computational study of the VCl3 molecule.

  14. Characterization of B-H agostic compounds involved in the dehydrogenation of amine-boranes by group 4 metallocenes.

    PubMed

    Zhu, Jingwen; Zins, Emilie-Laure; Alikhani, Mohammad Esmaïl

    2016-12-01

    For over a decade, amine-borane has been considered as a potential chemical hydrogen vector in the context of a search for cleaner energy sources. When catalyzed by organometallic complexes, the reaction mechanisms currently considered involve the formation of β-BH agostic intermediates. A thorough understanding of these intermediates may constitute a crucial step toward the identification of ideal catalysts. Topological approaches such as QTAIM and ELF revealed to be particularly suitable for the description of β-agostic interactions. When studying model catalysts, accurate theoretical calculations may be carried out. However, for a comparison with experimental data, calculations should also be carried out on large organo-metallic species, often including transition metals belonging to the second or the third row. In such a case, DFT methods are particularly attractive. Unfortunately, triple-ζ all electrons basis sets are not easily available for heavy transition metal elements. Thus, a subtle balance should be reached between the affordable level of calculations and the required accuracy of the electronic description of the systems. Herein we propose the use of B3LYP functional in combination with the LanL2DZ pseudopotential for the metal atom and 6-311++G(2d,2p) basis set for the other atoms, followed by a single point using the DKH2 relativistic Hamiltonian in combination with the B3LYP/DZP-DKH level, as a "minimum level of theory" leading to a consistent topological description of the interaction within the ELF and QTAIM framework, in the context of isolated (gas-phase) group 4 metallocene catalysts.

  15. Toxic Hazards Research Unit

    NASA Technical Reports Server (NTRS)

    Macewen, J. D.; Vernot, E. H.

    1971-01-01

    The activities of the Toxic Hazards Research Unit (THRU) for the period of June 1970 through May 1971 reviewed. Modification of the animal exposure facilities primarily for improved human safety but also for experimental integrity and continuity are discussed. Acute toxicity experiments were conducted on hydrogen fluoride (HF), hydrogen chloride (HCl), nitrogen dioxide (NO2), and hydrogen cyanide (HCN) both singly and in combination with carbon dioxide (CO). Additional acute toxicity experiments were conducted on oxygen difluoride (OF2) and chlorine pentafluoride (ClF5). Subacute toxicity studies were conducted on methylisobutylketone and dichloromethane (methylene dichloride). The interim results of further chronic toxicity experiments on monomethylhydrazine (MMH) are also described.

  16. Synthetic, Spectroscopic and Biocidal Aspects of Heterobimetallic Complexes Comprising Platinum(II) and a Group Four or Fourteen Element

    PubMed Central

    Sharma, Kripa

    2000-01-01

    Heterobimetallic complexes with varying amines have been synthesized by the reaction of [Pt(C2H8N2)2]Cl2 with group four or fourteen organometallic dichlorides, viz., R2MCl2 and Cp2M'Cl2 in a 1:2 molar ratio in MeOH (where M=Si or Sn, M'= Ti or Zr and R=Ph or Me). These complexes have been characterized by elemental analysis, molecular weight determinations, magnetic measurements, conductance, IR, 1H NMR and electronic spectra. The spectral data suggest a square planar geometry for all the complexes. Conductivity data suggest that they behave as electrolytes. These monometallic precursors along with their complexes have been screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential. PMID:18475917

  17. Oligomerization of 2-chloroallyl alcohol by 2-pyridinecarboxylate complex of chromium(III) - new highly active and selective catalyst.

    PubMed

    Drzeżdżon, Joanna; Sikorski, Artur; Chmurzyński, Lech; Jacewicz, Dagmara

    2018-06-05

    The new 2-pyridinecarboxylate (2-pic) complex of chromium(III) has been designed and synthesized as a new highly active and selective oligomerization catalyst. The crystal structure of the new compound has been determined by X-ray diffraction. The composition and purity of [Cr(2-pic) 2 (OH 2 ) 2 ]NO 3 have been confirmed by several spectroscopic methods and the elemental analysis. Furthermore, the new complex has been investigated towards its catalytic activity for the oligomerization of 2-chloro-2-propen-1-ol under the atmospheric pressure and at room temperature. It has turned out that the novel catalyst exhibits a very high catalytic activity. Consequently, [Cr(2-pic) 2 (OH 2 ) 2 ]NO 3 belongs to a new generation of non-metallocene catalysts.

  18. Competitive adsorption between benzene and ethylene dichloride on activated carbon: The importance of concentration

    NASA Astrophysics Data System (ADS)

    Miao, T.; Tang, H. M.; Cheng, Z. X.

    2018-03-01

    In this work we studied breakthroughs of binary mixtures of benzene and ethylene dichloride on fixed activated carbons bed. The results show a series of assault concentrations on activated carbon bed influences the nature of the adsorption competition mechanism. Assault concentration were used to determine how competition of compound distribution. The results are discussed in terms of competing energetic and the underlying molecular mechanisms. The ratio of assault concentrations is main reason for determining selectivity.

  19. Monochloro non-bridged half-metallocene-type zirconium complexes containing phosphine oxide-(thio)phenolate chelating ligands as efficient ethylene polymerization catalysts.

    PubMed

    Tang, Xiao-Yan; Wang, Yong-Xia; Liu, San-Rong; Liu, Jing-Yu; Li, Yue-Sheng

    2013-01-14

    A series of novel monochloro half-zirconocene complexes containing phosphine oxide-(thio)phenolate chelating ligands of the type, ClCp'Zr[X-2-R(1)-4-R(2)-6-(Ph(2)P=O)C(6)H(2)](2) (Cp' = C(5)H(5), 2a: X = O, R(1) = Ph, R(2) = H; 2b: X = O, R(1) = F, R(2) = H; 2c: X = O, R(1) = (t)Bu, R(2) = H; 2d: X = O, R(1) = R(2) = (t)Bu; 2e: X = O, R(1) = SiMe(3), R(2) = H; 2f: X = S, R(1) = SiMe(3), R(2) = H; Cp' = C(5)Me(5), 2g: X = O, R(1) = SiMe(3), R(2) = H), have been synthesized in high yields. These complexes were identified by (1)H {(13)C} NMR and elemental analyses. Structures for 2b, 2c and 2f were further confirmed by X-ray crystallography. Structural characterization of these complexes reveals crowded environments around the zirconium. Complexes 2b and 2c adopt six-coordinate, distorted octahedral geometry around the zirconium center, in which the equatorial positions are occupied by three oxygen atoms of two chelating phosphine oxide-bridged phenolate ligands and a chlorine atom. The cyclopentadienyl ring and one oxygen atom of the ligand are coordinated on the axial position. Complex 2f also folds a six-coordinate, distorted octahedral geometry around the Zr center, consisting of a Cp-Zr-O (in P=O) axis [177.16°] and a distorted plane of two sulfur atoms and one oxygen atom of two chelating phosphine oxide-bridged thiophenolate ligands as well as a chlorine atom. When activated by modified methylaluminoxane (MMAO), all the complexes exhibited high activities towards ethylene polymerization at high temperature (75 °C), giving high molecular weight polymers with unimodal molecular weight distribution. The formation of 14-electron, cationic metal alkyl species might come from the Zr-O (in phenol ring) bond cleavage based on the DFT calculations study.

  20. Synthesis and use of (perfluoroaryl) fluoro-aluminate anion

    DOEpatents

    Marks, T.J.; Chen, Y.X.

    1998-12-29

    A trityl perfluorophenyl alumninate such as tris(2,2{prime},2{double_prime}nonafluorobiphenyl) fluoroaluminate (PBA{sup {minus}}) and its role as a cocatalyst in metallocene-mediated olefin polymerization is disclosed. 4 figs.

  1. A one-pot synthesis of bis(phenylimino)thiazolidines from ketene N,S-acetals and [Formula: see text],[Formula: see text]-diphenyloxalimidoyl dichloride.

    PubMed

    Yavari, Issa; Zahedi, Nooshin; Baoosi, Leila; Skoulika, Stavroula

    2018-02-01

    A synthesis of functionalized 4,5-bis(phenylimino)-1,3-thiazolidine-2-ylidenes via a simple reaction between ketene [Formula: see text]-acetals (derived from isothiocyanates and acetonitrile derivatives) with N,[Formula: see text]-diphenyloxalimidoyl dichloride in the presence of KOH in DMF is described. When CS[Formula: see text] was used as the heterocumulene component, the reaction led to the formation of 4,5-bis(phenylimino)-1,3-dithiolan-2-ylidene derivatives, in moderate to good yields.

  2. Conversion of aryl iodides into aryliodine(III) dichlorides by an oxidative halogenation strategy using 30% aqueous hydrogen peroxide in fluorinated alcohol.

    PubMed

    Podgorsek, Ajda; Iskra, Jernej

    2010-04-20

    Oxidative chlorination with HCl/H2O2 in 1,1,1-trifluoroethanol was used to transform aryl iodides into aryliodine(III) dihalides. In this instance 1,1,1-trifluoroethanol is not only the reaction medium, but is also an activator of hydrogen peroxide for the oxidation of hydrochloric acid to molecular chlorine. Aryliodine(III) dichlorides were formed in 72-91% isolated yields in the reaction of aryl iodides with 30% aqueous hydrogen peroxide and hydrochloric acid at ambient temperature. A study of the effect that substituents on the aromatic ring have on the formation and stability of aryliodine(III) dichlorides shows that the transformation is easier to achieve in the presence of the electron-donating groups (i.e. methoxy), but in this case the products rapidly decompose under the reported reaction conditions to form chlorinated arenes. The results suggest that oxidation of hydrogen chloride with hydrogen peroxide is the initial reaction step, while direct oxidation of aryl iodide with hydrogen peroxide is less likely to occur.

  3. A homologous series of regioselectively tetradeprotonated group 8 metallocenes: new inverse crown ring compounds synthesized via a mixed sodium-magnesium tris(diisopropylamide) synergic base.

    PubMed

    Andrikopoulos, Prokopis C; Armstrong, David R; Clegg, William; Gilfillan, Carly J; Hevia, Eva; Kennedy, Alan R; Mulvey, Robert E; O'Hara, Charles T; Parkinson, John A; Tooke, Duncan M

    2004-09-22

    Subjecting ferrocene, ruthenocene, or osmocene to the synergic amide base sodium-magnesium tris(diisopropylamido) affords a unique homologous series of metallocene derivatives of general formula [(M(C(5)H(3))(2))Na(4)Mg(4)(i-Pr(2)N)(8)] (where M = Fe (1), Ru (2), or Os (3)). X-ray crystallographic studies of 1-3 reveal a common molecular "inverse crown" structure comprising a 16-membered [(NaNMgN)(4)](4+) "host" ring and a metallocenetetraide [M(C(5)H(3))(2)](4-) "guest" core, the cleaved protons of which are lost selectively from the 1, 1', 3, and 3'-positions. Variable-temperature NMR spectroscopic studies indicate that 1, 2, and 3 each exist as two distinct interconverting conformers in arene solution, the rates of exchange of which have been calculated using coalescence and EXSY NMR measurements.

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

    Kuzmin, Stanislav L.; Wesolowski, Michal J.; Duley, Walter W.

    A new type of metal-organic composition consisting of clusters of nanoparticles has been synthesised by laser irradiation of metallocene/benzene solutions. The metallocene molecules in this reaction become the source of the metal. Exposure to high-energy femtosecond laser pulses dehydrogenate benzene molecules and initiate the high-temperature high-pressure conditions that results in the synthesis of new materials. Irradiation experiments have been carried out on ferrocene/benzene and on other solutions. With ferrocene the synthesis of a new compound has been confirmed by X-ray powder diffraction as the peaks detected do not correspond to any known substance in the Crystallography Open Database. Theoretical simulationmore » of the periodic structure of this new carbide predicts that it has hexagonal symmetry and a unit cell with a = 3.2A and c =2.8A. The exact structure is still uncertain but may be determined from scanning tunneling microscope (STM) studies.« less

  5. Synthesis, characterization, and reactivity of the first uranium metallocene 1,2 bis(diphenylphosphino)acetylene complexes.

    DOE PAGES

    Pagano, Justin Kane; Scott, Brian Lindley; Kiplinger, Jaqueline Loetsch

    2018-06-09

    Two new uranium metallacyclopropenes, (C 5Me 4R) 2U(η 2-Ph 2PC=CPPh 2) (R = Me, Et) were prepared by reducing the corresponding (C 5Me 4R) 2UCl 2 complexes with KC 8 in the presence of 1,2-bis(diphenylphosphino)acetylene (Ph 2P–C≡C–PPh 2). Both compounds were fully characterized by a combination of elemental analysis and multinuclear NMR, UV–visible–NIR, and IR spectroscopies. Differences in the electronic spectra of these novel compounds and the known (C 5Me 5) 2U(η 2-Me 3SiC=CSiMe 3) are discussed. Finally, also presented is the solid-state structure of (C 5Me 4Et) 2U(η 2-Ph 2PC=CPPh 2), which reveals significant distortions of the coordinated 1,2-bis(diphenylphosphino)acetylenemore » (Ph 2P–C≡C–PPh 2) ligand.« less

  6. Synthesis, characterization, and reactivity of the first uranium metallocene 1,2 bis(diphenylphosphino)acetylene complexes.

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

    Pagano, Justin Kane; Scott, Brian Lindley; Kiplinger, Jaqueline Loetsch

    Two new uranium metallacyclopropenes, (C 5Me 4R) 2U(η 2-Ph 2PC=CPPh 2) (R = Me, Et) were prepared by reducing the corresponding (C 5Me 4R) 2UCl 2 complexes with KC 8 in the presence of 1,2-bis(diphenylphosphino)acetylene (Ph 2P–C≡C–PPh 2). Both compounds were fully characterized by a combination of elemental analysis and multinuclear NMR, UV–visible–NIR, and IR spectroscopies. Differences in the electronic spectra of these novel compounds and the known (C 5Me 5) 2U(η 2-Me 3SiC=CSiMe 3) are discussed. Finally, also presented is the solid-state structure of (C 5Me 4Et) 2U(η 2-Ph 2PC=CPPh 2), which reveals significant distortions of the coordinated 1,2-bis(diphenylphosphino)acetylenemore » (Ph 2P–C≡C–PPh 2) ligand.« less

  7. Bis(1,3-di-tert-butylimidazolin-2-iminato) titanium complexes as effective catalysts for the monodisperse polymerization of propylene.

    PubMed

    Sharma, Manab; Yameen, Haneen Simaan; Tumanskii, Boris; Filimon, Sabina-Alexandra; Tamm, Matthias; Eisen, Moris S

    2012-10-17

    The use of bis(1,3-di-tert-butylimidazolin-2-iminato) titanium dichloride (1) and dimethyl (2) complexes in the polymerization of propylene is presented. The complexes were activated using different amounts of methylalumoxane (MAO), giving in each case a very active catalytic mixture and producing polymers with a narrow molecular weight distribution (polydispersity = 1.10). The use of the cocatalyst triphenylcarbenium (trityl) tetra(pentafluorophenyl)borate totally inhibits the reaction, producing the corresponding bis(1,3-di-tert-butylimidazolin-2-iminato) titanium(III) methyl complex, the trityl radical ((•)CPh(3)), the anionic MeB(C(6)F(5))(4)(-), B(C(6)F(5))(3), and the bis(1,3-di-tert-butylimidazolin-2-iminato) titanium(IV) dimethyl·B(C(6)F(5))(3) complex. The use of a combination of physical methods such as NMR, ESR-C(60), and MALDI-TOF analyses enabled us to propose a plausible mechanism for the polymerization of propylene, presenting that the polymerization is mainly carried out in a living fashion. In addition, we present a slow equilibrium toward a small amount of a dormant species responsible for 2,1-misinsertions and chain transfer processes.

  8. Kinetics of initiation, propagation, and termination for the [rac-(C(2)H(4)(1-indenyl)(2))ZrMe][MeB(C(6)F(5))(3)]-catalyzed polymerization of 1-hexene.

    PubMed

    Liu, Z; Somsook, E; White, C B; Rosaaen, K A; Landis, C R

    2001-11-14

    Metallocene-catalyzed polymerization of 1-alkenes offers fine control of critical polymer attributes such as molecular weight, polydispersity, tacticity, and comonomer incorporation. Enormous effort has been expended on the synthesis and discovery of new catalysts and activators, but elementary aspects of the catalytic processes remain unclear. For example, it is unclear how the catalyst is distributed among active and dormant sites and how this distribution influences the order in monomer for the propagation rates, for which widely varying values are reported. Similarly, although empirical relationships between average molecular weights and monomer have been established for many systems, the underlying mechanisms of chain termination are unclear. Another area of intense interest concerns the role of ion-pairing in controlling the activity and termination mechanisms of metallocene-catalyzed polymerizations. Herein we report the application of quenched-flow kinetics, active site counting, polymer microstructure analysis, and molecular weight distribution analysis to the determination of fundamental rate laws for initiation, propagation, and termination for the polymerization of 1-hexene in toluene solution as catalyzed by the contact ion-pair, [rac-(C(2)H(4)(1-indenyl)(2))ZrMe][MeB(C(6)F(5))(3)] (1) over the temperature range of -10 to 50 degrees C. Highly isotactic (>99% mmmm) poly-1-hexene is produced with no apparent enchained regioerrors. Initiation and propagation processes are first order in the concentrations of 1-hexene and 1 but independent of excess borane or the addition of the contact ion-pair [PhNMe(3)][MeB(C(6)F(5))(3)]. Active site counting and the reaction kinetics provide no evidence of catalyst accumulation in dormant or inactive sites. Initiation is slower than propagation by a factor of 70. The principal termination process is the formation of unsaturates of two types: vinylidene end groups that arise from termination after a 1,2 insertion and vinylene end groups that follow 2,1 insertions. The rate law for the former termination process is independent of the 1-hexene concentration, whereas the latter is first order. Analysis of (13)C-labeled polymer provides support for a mechanism of vinylene end group formation that is not chain transfer to monomer. Deterministic modeling of the molecular weight distributions using the fundamental rate laws and kinetic constants demonstrates the robustness of the kinetic analysis. Comparisons of insertion frequencies with estimated limits on the rates of ion-pair symmetrization obtained by NMR suggest that ion-pair separation prior to insertion is not required, but the analysis requires assumptions that cannot be validated.

  9. The Lewis superacid Al[N(C6F5)2]3 and its higher homolog Ga[N(C6F5)2]3 – structural features, theoretical investigation and reactions of a metal amide with higher fluoride ion affinity than SbF5† †Electronic supplementary information (ESI) available. CCDC 1557072–1557076. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc03988c

    PubMed Central

    Kögel, J. F.; Sorokin, D. A.; Khvorost, A.; Scott, M.; Harms, K.; Himmel, D.; Krossing, I.

    2017-01-01

    Herein we present the synthesis of the two Lewis acids Al[N(C6F5)2]3 (ALTA) and Ga[N(C6F5)2]3 (GATA) via salt elimination reactions. The metal complexes were characterized by NMR-spectroscopic methods and X-ray diffraction analysis revealing the stabilization of the highly Lewis acidic metal centers by secondary metal–fluorine contacts. The Lewis acidic properties of Al[N(C6F5)2]3 and Ga[N(C6F5)2]3 are demonstrated by reactions with Lewis bases resulting in the formation of metallates accompanied by crucial structural changes. The two metallates [Cs(Tol)3]+[FAl(N(C6F5)2)3]– and [AsPh4]+[ClGa(N(C6F5)2)3]– contain interesting weakly coordinating anions. The reaction of Al[N(C6F5)2]3 with trityl fluoride yielded [CPh3]+[FAl(N(C6F5)2)3]– which could find application in the activation of metallocene polymerization catalysts. The qualitative Lewis acidity of Al[N(C6F5)2]3 and Ga[N(C6F5)2]3 was investigated by means of competition experiments for chloride ions in solution. DFT calculations yielded fluoride ion affinities in the gas phase (FIA) of 555 kJ mol–1 for Al[N(C6F5)2]3 and 472 kJ mol–1 for Ga[N(C6F5)2]3. Thus, Al[N(C6F5)2]3 can be considered a Lewis superacid with a fluoride affinity higher than SbF5 (493 kJ mol–1) whereas the FIA of the corresponding gallium complex is slightly below the threshold to Lewis superacidity. PMID:29629094

  10. Lifetime attributable risk as an alternative to effective dose to describe the risk of cancer for patients in diagnostic and therapeutic nuclear medicine.

    PubMed

    Andersson, Martin; Eckerman, Keith; Mattsson, Sören

    2017-11-21

    The aim of this study is to implement lifetime attributable risk (LAR) predictions of cancer for patients of various age and gender, undergoing diagnostic investigations or treatments in nuclear medicine and to compare the outcome with a population risk estimate using effective dose and the International Commission on Radiological Protection risk coefficients. The radiation induced risk of cancer occurrence (incidence) or death from four nuclear medicine procedures are estimated for both male and female between 0 and 120 years. Estimations of cancer risk are performed using recommended administered activities for two diagnostic ( 18 F-FDG and 99m Tc-phosphonate complex) and two therapeutic ( 131 I-iodide and 223 Ra-dichloride) radiopharmaceuticals to illustrate the use of cancer risk estimations in nuclear medicine. For 18 F-FDG, the cancer incidence for a male of 5, 25, 50 and 75 years at exposure is 0.0021, 0.0010, 0.0008 and 0.0003, respectively. For 99m Tc phosphonates complex the corresponding values are 0.000 59, 0.000 34, 0.000 27 and 0.000 13, respectively. For an 131 I-iodide treatment with 3.7 GBq and 1% uptake 24 h after administration, the cancer incidence for a male of 25, 50 and 75 years at exposure is 0.041, 0.029 and 0.012, respectively. For 223 Ra-dichloride with an administration of 21.9 MBq the cancer incidence for a male of 25, 50 and 75 years is 0.31, 0.21 and 0.09, respectively. The LAR estimations are more suitable in health care situations involving individual patients or specific groups of patients than the health detriment based on effective dose, which represents a population average. The detriment consideration in effective dose adjusts the cancer incidence for suffering of non-lethal cancers while LAR predicts morbidity (incidence) or mortality (cancer). The advantages of these LARs are that they are gender and age specific, allowing risk estimations for specific patients or subgroups thus better representing individuals in health care than effective dose.

  11. Lifetime attributable risk as an alternative to effective dose to describe the risk of cancer for patients in diagnostic and therapeutic nuclear medicine

    NASA Astrophysics Data System (ADS)

    Andersson, Martin; Eckerman, Keith; Mattsson, Sören

    2017-12-01

    The aim of this study is to implement lifetime attributable risk (LAR) predictions of cancer for patients of various age and gender, undergoing diagnostic investigations or treatments in nuclear medicine and to compare the outcome with a population risk estimate using effective dose and the International Commission on Radiological Protection risk coefficients. The radiation induced risk of cancer occurrence (incidence) or death from four nuclear medicine procedures are estimated for both male and female between 0 and 120 years. Estimations of cancer risk are performed using recommended administered activities for two diagnostic (18F-FDG and 99mTc-phosphonate complex) and two therapeutic (131I-iodide and 223Ra-dichloride) radiopharmaceuticals to illustrate the use of cancer risk estimations in nuclear medicine. For 18F-FDG, the cancer incidence for a male of 5, 25, 50 and 75 years at exposure is 0.0021, 0.0010, 0.0008 and 0.0003, respectively. For 99mTc phosphonates complex the corresponding values are 0.000 59, 0.000 34, 0.000 27 and 0.000 13, respectively. For an 131I-iodide treatment with 3.7 GBq and 1% uptake 24 h after administration, the cancer incidence for a male of 25, 50 and 75 years at exposure is 0.041, 0.029 and 0.012, respectively. For 223Ra-dichloride with an administration of 21.9 MBq the cancer incidence for a male of 25, 50 and 75 years is 0.31, 0.21 and 0.09, respectively. The LAR estimations are more suitable in health care situations involving individual patients or specific groups of patients than the health detriment based on effective dose, which represents a population average. The detriment consideration in effective dose adjusts the cancer incidence for suffering of non-lethal cancers while LAR predicts morbidity (incidence) or mortality (cancer). The advantages of these LARs are that they are gender and age specific, allowing risk estimations for specific patients or subgroups thus better representing individuals in health care than effective dose.

  12. Synthesis and use of (perfluoroaryl) fluoro-aluminate anion

    DOEpatents

    Marks, Tobin J.; Chen, You-Xian

    2001-01-01

    A trityl perfluorophenyl alumninate such as tris(2,2',2"-nonafluorobiphenyl)-fluoroaluminate (PBA.sup..crclbar.) and its role as a cocatalyst in metallocene-mediated olefin polymerization is disclosed. Gallium and indium analogs are also disclosed, as are analogs with different anyl groups or different numbers of flourine atoms thereon.

  13. Organo-Lewis acid as cocatalyst for cationic homogeneous Ziegler-Natta olefin polymerizations

    DOEpatents

    Marks, Tobin J.; Chen, You-Xian

    2001-01-01

    Organo-Lewis acids of the formula BR'R".sub.2 wherein B is boron, R' is fluorinated biphenyl, and R" is a fluorinated phenyl, fluorinated biphenyl, or fluorinated polycyclic fused ring group, and cationic metallocene complexes formed therewith. Such complexes are useful as polymerization catalysts.

  14. Organo-Lewis acid as cocatalyst for cationic homogeneous Ziegler-Natta olefin polymerizations

    DOEpatents

    Marks, Tobin J.; Chen, You-Xian

    2002-01-01

    Organo-Lewis acids of the formula BR'R".sub.2 wherein B is boron, R' is fluorinated biphenyl, and R" is a fluorinated phenyl, fluorinated biphenyl, or fluorinated polycyclic fused ring group, and cationic metallocene complexes formed therewith. Such complexes are useful as polymerization catalysts.

  15. Manual Solid-Phase Peptide Synthesis of Metallocene-Peptide Bioconjugates

    ERIC Educational Resources Information Center

    Kirin, Srecko I.; Noor, Fozia; Metzler-Nolte, Nils; Mier, Walter

    2007-01-01

    A simple and relatively inexpensive procedure for preparing a biologically active peptide using solid phase peptide synthesis (SPPS) is described. Fourth-year undergraduate students have gained firsthand experience from the solid-phase synthesis techniques and they have become familiar with modern analytical techniques based on the particular…

  16. A to Z List of Cancer Drugs

    MedlinePlus

    ... T) Purinethol (Mercaptopurine) Purixan (Mercaptopurine) Q [No Entries] R Radium 223 Dichloride Raloxifene Hydrochloride Ramucirumab Rasburicase R-CHOP R-CVP Recombinant Human Papillomavirus (HPV) Bivalent ...

  17. Activation of SO2 with [(η(5) -C5 Me5 )2 Ln(THF)2 ] (Ln=Eu, Yb) leading to dithionite and sulfinate complexes.

    PubMed

    Klementyeva, Svetlana V; Gamer, Michael T; Schmidt, Anna-Corina; Meyer, Karsten; Konchenko, Sergey N; Roesky, Peter W

    2014-10-13

    The reaction of decamethylytterbocene [(η(5) -C5 Me5 )2 Yb(THF)2 ] with SO2 at low temperature gave two new compounds, namely, the Yb(III) dithionite/sulfinate complex [{(η(5) -C5 Me5 )2 Yb(μ3 ,1κ(2) O(1,3) ,2κ(3) O(2,2',4) -S2 O4 )}2 {(η(5) -C5 Me5 )Yb(μ,1κO,2κO'-C5 Me5 SO2 )}2 ] (1) and the Yb(III) dithionite complex [{(η(5) -C5 Me5 )2 Yb}2 (μ,1κ(2) O(1,3) ,2κ(2) O(2,4) -S2 O4 )] (2). After extraction of 1, the mixture was heated to give the dinuclear tetrasulfinate complex [{(η(5) -C5 Me5 )Yb}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 a). In contrast, from the reaction of [(η(5) -C5 Me5 )2 Eu(THF)2 ] with SO2 only the tetrasulfinate complex [{(η(5) -C5 Me5 )Eu}2 (μ,κO,κO'-C5 Me5 SO2 )4 ] (3 b) was isolated. Two major reaction pathways were observed: 1) reductive coupling of two SO2 molecules to form the dithionite anion S2 O4 (2-) ; and 2) nucleophilic attack of one metallocene C5 Me5 ligand on the sulfur atom of SO2 . The compounds presented are the first dithionite and sulfinate complexes of the f-elements. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Thiopyridazine-Based Palladium and Platinum Boratrane Complexes.

    PubMed

    Holler, Stefan; Tüchler, Michael; Steller, Beate G; Belaj, Ferdinand; Veiros, Luis F; Kirchner, Karl; Mösch-Zanetti, Nadia C

    2018-06-07

    Palladium and platinum boratrane complexes of the type [M{B(Pn Me, tBu ) 3 }(PPh 3 )] (M = Pd 1, Pt 2b) have been prepared via the reaction of the soft scorpionate ligand potassium tris(4-methyl-6- tert-butyl-3-thiopyridazinyl)borate KTn Me, tBu with bis(triphenylphosphine)metal(II) dichloride. While reaction with the Pd precursor allowed direct isolation of a symmetric boratrane complex, the Pt analogue led to the hydrido compound [Pt{B(Pn Me, tBu ) 3 }(PPh 3 )H]Cl (2a), which after reaction with a base gave 2b. Subsequent oxidation with Br 2 and I 2 , respectively, led to the dihalide compounds of the molecular formula [M{B(Pn Me, tBu ) 3 }X 2 ] (3a,b-4a,b). Halide abstraction with Ag(SbF 6 ) further gave interesting cationic compounds of either dimeric [Pd{B(Pn Me, tBu ) 3 }X] 2 (SbF 6 ) 2 (5a,b) or monomeric [Pd{B(Pn Me, tBu ) 3 }(NCMe) 2 ](SbF 6 ) (6) nature. All compounds were spectroscopically and X-ray crystallographically characterized revealing strong metal to boron interactions. DFT calculations of 1, 2a, and 2b confirm the strong M-B interaction and a high positive charge on the metal centers.

  19. De novo design of chiral organotin cancer drug candidates: validation of enantiopreferential binding to molecular target DNA and 5'-GMP by UV-visible, fluorescence, (1)H and (31)P NMR.

    PubMed

    Arjmand, Farukh; Sharma, Girish Chandra; Sayeed, Fatima; Muddassir, Mohd; Tabassum, Sartaj

    2011-12-02

    N,N-bis[(R-/S-)-1-benzyl-2-ethoxyethane] tin (IV) complexes were synthesized by applying de novo design strategy by the condensation reaction of (R-/S-)2-amino-2-phenylethanol and dibromoethane in presence of dimethyltin dichloride and thoroughly characterized by elemental analysis, conductivity measurements, IR, ESI-MS, (1)H, (13)C and (119)Sn, multinuclear NMR spectroscopy and XRD study. Enantioselective and specific binding profile of R-enantiomer 1 in comparison to S-enantiomer 2 with ultimate molecular target CT-DNA was validated by UV-visible, fluorescence, circular dichroism, (1)H and (31)P NMR techniques. This was further corroborated well by interaction of 1 and 2 with 5'-GMP. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Urine Preservative

    NASA Technical Reports Server (NTRS)

    Smith, Scott M. (Inventor); Nillen, Jeannie (Inventor)

    2001-01-01

    Disclosed is CPG, a combination of a chlorhexidine salt (such as chlorhexidine digluconate, chlorhexidine diacetate, or chlorhexidine dichloride) and n-propyl gallate that can be used at ambient temperatures as a urine preservative.

  1. Understanding the molecular behavior of organotin compounds to design their effective use as agrochemicals: exploration via quantum chemistry and experiments.

    PubMed

    Ramalho, Teodorico C; Rocha, Marcus V J; da Cunha, Elaine F F; Oliveira, Luiz C A; Carvalho, Kele T C

    2010-10-01

    The high frequency of contamination by herbicides suggests the need for more active and selective agrochemicals. Organotin compounds are the active component of some herbicides, such as Du-Ter and Brestan, which is also a potent inhibitor of the F1Fo ATP Synthase. That is a key enzyme, because the ATP production is one of the major chemical reactions in living organisms. Thus ATP Synthase is regarded as a prime target for organotin compounds. In this line, molecular modeling studies and DFT calculations were performed in order to understand the molecular behavior of those compounds in solution. In addition, we investigated the reaction mechanism by ESI-MS analyses of the diphenyltin dichloride. Our findings indicate that an unstable key-intermediate generated in situ might take place in the reaction with ATP Synthase.

  2. Development of the titanium–TADDOLate-catalyzed asymmetric fluorination of β-ketoesters

    PubMed Central

    Hintermann, Lukas; Perseghini, Mauro

    2011-01-01

    Summary Titanium-based Lewis acids catalyze the α-fluorination of β-ketoesters by electrophilic N–F-fluorinating reagents. Asymmetric catalysis with TADDOLato–titanium(IV) dichloride (TADDOL = α,α,α',α'-tetraaryl-(1,3-dioxolane-4,5-diyl)-dimethanol) Lewis acids produces enantiomerically enriched α-fluorinated β-ketoesters in up to 91% enantiomeric excess, with either F–TEDA (1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)) in acetonitrile solution or NFSI (N-fluorobenzenesulfonimide) in dichloromethane solution as fluorinating reagents. The effects of various reaction parameters and of the TADDOL ligand structure on the catalytic activity and enantioselectivity were investigated. The absolute configuration of several fluorination products was assigned through correlation. Evidence for ionization of the catalyst complex by chloride dissociation, followed by generation of titanium β-ketoenolates as key reaction intermediates, was obtained. Based on the experimental findings, a general mechanistic sketch and a steric model of induction are proposed. PMID:22043253

  3. Pentadienyl chemistry of the heavy alkaline-earth metals revisited.

    PubMed

    Reiners, Matthias; Fecker, Ann Christin; Freytag, Matthias; Jones, Peter G; Walter, Marc D

    2014-05-14

    Open-metallocenes of the heavy alkaline-earth metals [(η(5)-Pdl')2M(thf)n] (M = Ca (1), Sr (2), n = 1; M = Ba (3), n = 2; Pdl' = 2,4-tBu2C5H5) are readily prepared by salt-metathesis between MI2 and KPdl' and characterized by NMR spectroscopy and X-ray diffraction studies.

  4. Synthesis, crystal structure and biological activity of the Schiff base organotin(IV) complexes based on salicylaldehyde-o-aminophenol

    NASA Astrophysics Data System (ADS)

    Tan, Yu-Xing; Zhang, Zhi-Jian; Liu, Yang; Yu, Jiang-Xi; Zhu, Xiao-Ming; Kuang, Dai-Zhi; Jiang, Wu-Jiu

    2017-12-01

    Schiff base organotin(IV) complexes C1 ∼ C5b have been synthesized via the reaction of the substituted salicylaldehyde-o-aminophenol Schiff base ligands (L1 ∼ L3) with the dibenzyltin dichloride, n-butyltin trichloride or dibutyltin oxide, respectively. The complexes have been characterized by IR, UV-Vis, 1H NMR, 13C NMR spectra, elemental analysis and the crystal structures have been determined by X-ray diffraction. The anticancer activity of the Schiff base ligand and complexes C1 ∼ C5b against five species of cancer cell which are Hela, MCF7, HepG2, Colo205, NCIsbnd H460 were tested respectively, the tests showed that C1 ∼ C5b exhibited significant anticancer activity for the cancer cells in comparison with the ligand, and the activity was greater than carboplatin.

  5. Chemistry of 1,1,2,2,9,9,10,10-octafluoro-[2,2]-paracyclophane: Its synthesis and reactions

    NASA Astrophysics Data System (ADS)

    Duan, Jian-Xin

    This dissertation describes the first example of the synthesis of 1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane (AF4) under non-high-dilution conditions. Under very mild reaction conditions, bis-p-(chlorodifluoromethyl)benzene (TFPX dichloride) and its derivatives reacted with Zn dust in N,N-dimethyl acetamide (DMA) (Zinc method) affording the corresponding AF4 and its derivatives in moderate to good yields. Purification of products was also studied and an efficient purification process was developed. A new and very cheap method for preparation of TFPX dichloride is also disclosed. Using the very cheap fluorinating reagent, anhydrous hydrogen fluoride (AHF), 1,4-bis(trichloromethyl)benezene or its derivatives were converted to TFPX and its derivatives in high yields (F/Cl exchange reaction). With the success of the Zinc method and F/Cl exchange reaction, highly pure AF4 thus can be provided to the semiconductor industry and academy research scientists in large quantity and at a very low price. Starting from AF4, numerous AF4 derivatives were synthesized using convenient reaction conditions. Reaction of AF4 with fuming nitric acid at room temperature gave mono-nitroAF4 in almost quantitative yield. Reduction of the mono-nitroAF4 with iron powder in the presence of HCl in alcoholic solvent gave the aminoAF4 in 90% yield. Via the diazonium salt intermediate, iodoAF4 was also obtained in good yield. Under similar reaction conditions, disubstituted AF4 derivatives were also prepared in good yields. Heating a mixture of AF4, trifluoroacetyl peroxide and dichloromethane gave the trifluoromethylated dimeric AF4 as a mixture of diastereomers. When these products were heated to 170--180°C in the presence of I 2, 4-trifluoromethyl-AF4 was obtained in almost 87% yield. X-ray structural analysis showed that the C-C bond connecting the two cyclophane moieties to be longer than the normal C-C bond. Kinetic studies, conducted in the presence of excess amount of hydrogen donor, showed this bond to be quite weak. Oxidation of AF4 with HIO3 in the presence of catalytic amount of H2SO4 in trifluoroacetic acid gave AF4 quinone in one step. AF4 quinone can be easily reduced to the hydroquinone by Na 2S2O4 aqueous solution.

  6. Illustrating Catalysis with Interlocking Building Blocks: Correlation between Structure of a Metallocene Catalyst and the Stereoregularity of Polypropylene

    ERIC Educational Resources Information Center

    Horikoshi, Ryo; Kobayashi, Yoji; Kageyama, Hiroshi

    2013-01-01

    Catalysis with transition-metal complexes is a part of the inorganic chemistry curriculum and a challenging topic for upper-level undergraduate and graduate students. A hands-on teaching aid has been developed for use during conventional lectures to help students understand these catalytic reactions. A unique method of illustrating the…

  7. Polyorganometallosiloxane-2- or -4-pyridine coatings

    DOEpatents

    Sugama, Toshifumi

    1997-01-01

    A new family of polyorganometallosiloxane-2- or -4-pyridine compounds are provided for corrosion resistant coatings on light metals such as aluminum, magnesium, zinc, steel and their allows. The novel compounds contain backbones modified by metal alkoxides, metallocenes and metallophthalocyanates where the metal is Zr, Ti, Mo, V, Hf, Nb, Si, B and combinations thereof. Methods of making the new compounds are also provided.

  8. Radium-223 for Advanced Prostate Cancer

    Cancer.gov

    A summary of results from a phase III trial that compared radium-223 dichloride plus the best standard of care versus a placebo plus the best standard of care in men with metastatic, castration-resistant prostate cancer.

  9. Preparation of titanium diboride powder

    DOEpatents

    Brynestad, Jorulf; Bamberger, Carlos E.

    1985-01-01

    Finely-divided titanium diboride or zirconium diboride powders are formed by reacting gaseous boron trichloride with a material selected from the group consisting of titanium powder, zirconium powder, titanium dichloride powder, titanium trichloride powder, and gaseous titanium trichloride.

  10. 1. BUILDING 411A. VIEW TO NORTHEAST. Rocky Mountain Arsenal, ...

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

    1. BUILDING 411A. VIEW TO NORTHEAST. - Rocky Mountain Arsenal, Sulfur Monochloride & Dichloride Manufacturing, 1003 feet South of December Seventh Avenue; 412 feet East of D Street, Commerce City, Adams County, CO

  11. Preparation of metal diboride powders

    DOEpatents

    Brynestad, J.; Bamberger, C.E.

    Finely-divided titanium diboride or zirconium diboride powders are formed by reacting gaseous boron trichloride with a material selected from the group of consisting of titanium powder, zirconium powder, titanium dichloride powder, titanium trichloride powder, and gaseous titanium trichloride.

  12. AUTOMOTIVE EMISSIONS OF ETHYLENE DIBROMIDE

    EPA Science Inventory

    Ethylene dibromide, a suspected carcinogen, and ethylene dichloride are commonly used in leaded gasoline as scavengers. Ethylene dibromide emission rates were determined from seven automobiles which had a wide range of control devices, ranging from totally uncontrolled to evapora...

  13. 40 CFR Table 8 to Subpart Ffff of... - Partially Soluble Hazardous Air Pollutants

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... acrylate 140885 34. Ethylbenzene 100414 35. Ethylene oxide 75218 36. Ethylidene dichloride 75343 37.... Methyl-t-butyl ether 1634044 42. Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline...

  14. 40 CFR Table 5 to Subpart U of... - Known Organic HAP Emitted From the Production of Elastomer Products

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) ✔ Epichlorohydrin (106898) ✔ Ethylbenzene (100414) ✔ ✔ Ethylene Dichloride (107062) ✔ Ethylene Oxide (75218... Rubber. EPI = Epichlorohydrin Rubber. EPR = Ethylene Propylene Rubber. HBR = Halobutyl Rubber. HYP...

  15. Polyorganometallosiloxane-2- or -4-pyridine coatings

    DOEpatents

    Sugama, T.

    1997-12-30

    A new family of polyorganometallosiloxane-2- or -4-pyridine compounds are provided for corrosion resistant coatings on light metals such as aluminum, magnesium, zinc, steel and their alloys. The novel compounds contain backbones modified by metal alkoxides, metallocenes and metallophthalocyanates where the metal is Zr, Ti, Mo, V, Hf, Nb, Si, B and combinations thereof. Methods of making the new compounds are also provided. 13 figs.

  16. IMMUNOTOXICITY OF INDIVIDUAL ORGANOTIN COMPOUNDS IN SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    Organotins, used as stabilizers for polyvinyl chloride pipe, leach into drinking water from supply pipes and may cause multisystem toxicity, including immunotoxicity. We assessed immune function in Sprague-Dawley rats exposed to dibutyltin dichloride (DBTC) or dimethyltin dichlor...

  17. 77 FR 26751 - Integrated Risk Information System (IRIS); Announcement of 2012 Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ...-41-4. ethylene oxide (cancer) 75-21-8. formaldehyde \\1\\ 50-00-0. hexabromocyclododecane (mixed 3194...\\. octamethylcyclotetrasiloxane 556-67-2 FY13. (D4) \\2\\. 1,2-dichloroethane (ethylene 107-06-2 FY14. dichloride) \\1,3...

  18. Synthesis, characterization, and reactivity of pentamethylcyclopentadienyl complexes of divalent cobalt and nickel

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

    Smith, Michael Edward

    1993-10-01

    The thesis is divided into the following 4 chapters: synthesis, characterization, and reactivity of trinuclear pentamethylcyclopentadienyl cobalt and nickel clusters with triply-bridging methylidyne groups; chemical and physical properties of pentamethylcyclopentadienyl acetylacetonate complexes of Co(II) and Ni(II); synthesis, characterization, and reactivity of pentamethylcyclopentadienyl halide complexes of Co and Ni; and crystallographic studies of distortions in metallocenes with C 5-symmetrical cyclopentadienyl rings.

  19. The preparation of nanosized polyethylene particles via novel heterogeneous non-metallocene catalyst (m-CH3PhO)TiCl3/CNTs/AlEt3

    NASA Astrophysics Data System (ADS)

    Wang, J.; Guo, J. P.; Yi, J. J.; Huang, Q. G.; Li, H. M.; Li, Y. F.; Gao, K. J.; Yang, W. T.

    2014-08-01

    This paper reports the preparation of coral-shaped topological morphology nascent polyethylene (PE) particles promoted by the novel heterogeneous non-metallocene catalyst (m-CH3PhO)TiCl3/carbon nanotubes (CNTs), with AlEt3 used as a cocatalyst. Scanning electron microscope (SEM), high resolution transmission electron microscope (HR-TEM) and inductively coupled plasma (ICP) emission spectroscopy were used to determine the morphology of the catalyst particles and the content of (m-CH3PhO)TiCl3. The carbon nanotube surface was treated with Grignard Reagent prior to reacting with (m-CH3PhO)TiCl3. The catalyst system could effectively catalyze ethylene polymerization and ethylene with 1- hexene copolymerization, the catalytic activity could reach up to 5.8 kg/((gTi)h). Morphology of the obtained polymer particles by SEM and HR-TEM technique revealed that the nascent polyethylene particles looked like coral shape in micro-size. The multiwalled carbon nanotubes (MWCNTs) supported catalysts polymerized ethylene to form polymer nanocomposite in situ. The microscopic examination of this nanocomposite revealed that carbon nanoparticles in PE matrix had a good distribution and the cryogenically fractured surface was ductile-like when polymerization time was 2 min.

  20. News from Online: Industrial Chemicals and Polymers

    NASA Astrophysics Data System (ADS)

    Sweeney Judd, Carolyn

    1999-02-01

    Paper or plastic? I am asked this question every time I go grocery shopping. Asked another way, the question is, "Which polymer do you want?" To learn about polymers, go shopping at a great site from the University of Southern Mississippi, The Macrogalleria, a cyberwonderland of polymer fun at http://www.psrc.usm.edu/macrog/index.html . Plan to spend some time here. Bring along Chime and Shockwave plug-ins or download them from The Macrogalleria. The Macrogalleria shopping mall is divided into five levels. On the first level, Polymers are Everywhere at http:/ /www.psrc.usm.edu/macrog/floor1.html, you can visit stores selling sporting goods, food, and clothing. Learn about natural polymers in shoes and in French fries at http://www.psrc.usm.edu/macrog/natupoly.html . Find out about nylon in toothbrushes at http://www.psrc.usm.edu/macrog/nylon.html and about carbon fibers in tennis racquets at http://www.psrc.usm.edu/macrog /carfib.html-great graphics and even better chemistry. Skip up to level three for How They Work at http:/ /www.psrc.usm.edu/macrog/floor3.html. Take a look at the history of rubber on The Cross-linking Page at http:/ /www.psrc.usm.edu/macrog/xlink.html. Move on to level four for Makin' Polymers at http://www.psrc.usm.edu/macrog /floor4.html. Let's go right to the Ziegler-Natta Vinyl Polymerization at http://www.psrc.usm.edu/macrog/ziegler.html . Don't miss the humor in the initial explanation of the process. This page is excellent-with graphics, reactions, and a movie of a polymerization ( http://www.psrc.usm.edu/macrog/movies/zns.html ). This movie is worth seeing several times. Next take a look at another catalyst metallocene at http:/ /www.psrc.usm.edu/macrog/mcene.html. Explanations, graphics, and mechanisms help make this site worth visiting and great for teaching. Several people contributed to The Macrogalleria, with major contributions from Mark Michalovic of the University of Southern Mississippi. Grants were from POLYED, a joint committee of the American Chemical Society Divisions of Polymer Chemistry and Polymeric Materials: Science and Engineering and General Electric Corporation. The POLYED site, http:/ /chemdept.uwsp.edu/polyed/index.htm, is hosted by the University of Wisconsin at Stevens Point. This National Center for Polymer Education is another good place to go for information. More education is available at the Ziegler Research Group Home Page at http://www.chem.ucalgary.ca/groups/ziegler/index.html . Go to Metallocene as Olefin Polymerization Catalysis: An Introduction ( http://www.chem.ucalgary.ca/groups/ziegler/met_intro.html ) for historical accounts of metallocene and Ziegler-Natta catalysts. Movies are available here too. This Canadian site is well-documented and educational. Back at the University of Wisconsin-Madison, The Why Files site at http://whyfiles.news.wisc.edu helps bring important chemical and technology news to the public. Go to the archived files of October 1997 ( http://whyfiles.news.wisc.edu/shorties/catalyst.html ) to find information about the importance of low-temperature metallocene catalysts. The Why Files received funding from the National Science Foundation. Go here for science information in an easy-to-read format. One of the driving forces toward better catalysis is the attempt to reach 100% product, combining efficiency with lowered pollution. Companies can look to the Environmental Protection Agency for information: Environsense at http://es.epa.gov/ is pledged to offer "Common Sense Solutions to Environmental Problems". So where can we get these polymers? The American Chemical Society can help. Go to Chemcylopedia at http://pubs.acs.org/chemcy99/ for great information. Both purchasers and users of chemicals can benefit from this site. Searches can be made on the chemical or on the supplier. Information provided includes CAS Registry Numbers and special shipping requirements as well as potential applications. Do you remember that we started with paper? Let's end with information about making paper. Go to http://www.sci.fi /~saarives/pulpmfl.htm for Ahlstrom Machinery's Typical Offerings for Chemical Pulp Mills. Now this is a chemically rich plant that is worth the trip. Carolyn Sweeney Judd teaches at Houston Community College System, 1300 Holman, Houston, TX 77004; phone: 713/718-6315; email: cjudd@tenet.edu. World Wide Web Addresses The Macrogalleria http://www.psrc.usm.edu/macrog/index.html Polymers Are Everywhere http://www.psrc.usm.edu/macrog/floor1.html Natural Polymers http://www.psrc.usm.edu/macrog/natupoly.html Nylon http://www.psrc.usm.edu/macrog/nylon.html Carbon Fibers http://www.psrc.usm.edu/macrog/carfib.html How They Work http://www.psrc.usm.edu/macrog/floor3.html The Cross-linking Page http://www.psrc.usm.edu/macrog/xlink.html Makin' Polymers http://www.psrc.usm.edu/macrog/floor4.html Ziegler-Natta Vinyl Polymerization http://www.psrc.usm.edu/macrog/ziegler.html Syndiotactic Ziegler-Natta Polymerization (movie, Shockwave plug-in required for viewing) at http://www.psrc.usm.edu/macrog/movies/zns.html Metallocene Catalysis Polymerization http://www.psrc.usm.edu/macrog/mcene.html POLYED Welcome Page http://chemdept.uwsp.edu/polyed/index.htm Ziegler Research Group Home Page http://www.chem.ucalgary.ca/groups/ziegler/index.html Metallocene as Olefin Polymerization Catalysis: An Introduction at http://www.chem.ucalgary.ca/groups/ziegler/met_intro.html The Why Files http://whyfiles.news.wisc.edu Low-Temperature Metallocene Catalysts http://whyfiles.news.wisc.edu/shorties/catalyst.html Environsense http://es.epa.gov/ Chemcylopedia 99 http://pubs.acs.org/chemcy99/ Ahlstrom Machinery's Typical Offerings for Chemical Pulp Mills at http://www.sci.fi/~saarives/pulpmfl.htm access date for all sites: December 1998

  1. IRIS Toxicological Review and Summary Documents for Carbon Tetrachloride (Peer Review Plan)

    EPA Science Inventory

    Carbon tetrachloride is a volatile haloalkane with a wide range of industrial and chemical applications. It is produced commercially from chlorination of a variety of low molecular weight hydrocarbons such as carbon disulfide, methanol, methane, propane, and ethylene dichloride....

  2. 1,2-Ethylene Dichloride; Final Enforceable Consent Agreement and Testing Consent Order

    EPA Pesticide Factsheets

    This document announces that EPA has signed an enforceable testing Consent Order with the Dow Chemical Co, Vulcan Materials Co, Occidental Chemical Corp, Oxy Vinyls, LP, Georgia Gulf Corp, Westlake Chemical Corp, PPG Industries, Inc., and Formosa Plastics.

  3. Intravenous application of HI-6 salts (dichloride and dimethansulphonate) in pigs: comparison with pharmacokinetics profile after intramuscular administration.

    PubMed

    Zdarova Karasova, Jana; Zemek, Filip; Kunes, Martin; Kvetina, Jaroslav; Chladek, Jaroslav; Jun, Daniel; Bures, Jan; Tachecí, Ilja; Kuca, Kamil

    2013-01-01

    Oxime HI-6 is an acetylcholinesterase reactivator therapeutically efficient against nerve agents. Because of their physico-chemical properties, oximes are typically applied intramuscularly (i.m.). This route of administration has also some disadvantages, and alternative strategies ought to be examined. We evaluated the pharmacokinetic profiles of two HI-6 salts after their intravenous (i.v.) administration, and compare the results with the known pharmacokinetics after i.m. administration. Pigs were administered with HI-6 salts (i.v), either HI-6 dichloride (10.71 mg/kg) or molar equivalent HI-6 dimethansulphonate (13.59 mg/kg). Doses of the HI-6 salts corresponded with a standard HI-6 dichloride dose in one autoinjector (500 mg) and were recalculated for one kilogram of body weight. The main pharmacokinetic parameters are comparable after i.v. and i.m. HI-6 administration. The compared pharmacokinetic parameters were half-life, terminal rate constant, mean residence time of the molecule in the body, clearance, and the apparent volume in the terminal phase. The bioavailability after i.m. administration was comparable with that of i.v.; these results suggest that the oxime is well released from the muscle depot. Significant differences were found in parameters Cmax and Tmax which are important in cases of emergency when rapidity and bioavailability are paramount for the success of treatment. I.v. administration should solve the problem of rapid clearance. Infusion or bolus administration may be considered as a logical subsequent step in oxime treatment strategy. The main advantage is in maintenance of an effective therapeutic plasma concentration, a more easily achievable effective therapeutic concentration, and fewer local adverse reactions.

  4. IMMUNE FUNCTION IN RATS DEVELOPMENTALLY EXPOSED TO DIBUTYLTIN DICHLORIDE

    EPA Science Inventory

    Organotins are used commercially as pesticides, antifouling agents and stabilizers for polyvinyl chloride (PVC) pipe. Mono- and di-substituted methyl and butyltins, used in PVC pipe production, are of concern to the USEPA as they leach from supply pipes into drinking water and ha...

  5. THE DEVELOPMENTAL IMMUNOTOXICITY OF DIBUTYLTIN DICHLORIDE IN SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    Methyl- and butyltin compounds used as stabilizers in polyvinyl chloride (PVC) pipe production are of concern as they leach from supply pipes into drinking water and have been associated with multisystem toxicity. This study assessed immune function in Sprague-Dawley (CD) rats d...

  6. 77 FR 47539 - Paraquat Dichloride; Pesticide Tolerances

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-09

    ...). Food manufacturing (NAICS code 311). Pesticide manufacturing (NAICS code 32532). This listing is not... Federal Food, Drug, and Cosmetic Act (FFDCA). DATES: This regulation is effective August 9, 2012...? You may be potentially affected by this action if you are an agricultural producer, food manufacturer...

  7. Vibrationally high-resolved electronic spectra of MCl2 (M=C, Si, Ge, Sn, Pb) and photoelectron spectra of MCl2(.).

    PubMed

    Ran, Yibin; Pang, Min; Shen, Wei; Li, Ming; He, Rongxing

    2016-10-05

    We systematically studied the vibrational-resolved electronic spectra of group IV dichlorides using the Franck-Condon approximation combined with the Duschinsky and Herzberg-Teller effects in harmonic and anharmonic frameworks (only the simulation of absorption spectra includes the anharmonicity). Calculated results showed that the band shapes of simulated spectra are in accordance with those of the corresponding experimental or theoretical ones. We found that the symmetric bend mode in progression of absorption is the most active one, whereas the main contributor in photoelectron spectra is the symmetric stretching mode. Moreover, the Duschinsky and anharmonic effects exert weak influence on the absorption spectra, except for PbCl2 molecule. The theoretical insights presented in this work are significant in understanding the photophysical properties of MCl2 (M=C, Si, Ge, Sn, Pb) and studying the Herzberg-Teller and the anharmonic effects on the absorption spectra of new dichlorides of this main group. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Surface modification of calcium fluoro and hydroxyapatite by 1-octylphosphonic dichloride

    NASA Astrophysics Data System (ADS)

    Aissa, Abdallah; Agougui, Hassen; Debbabi, Mongi

    2011-08-01

    The reactivity of the surface of calcium hydroxyapatite (CaHAp) and fluorapatite (CaFAp) was tested and compared by grafting the 1-octylphosphonic dichloride (C 8H 17OPCl 2) using a molar ratio x = 2 or 4, x = n(organic)/ n(apatite). Successful synthesis was confirmed by different characterisation techniques such as X-ray powder diffraction patterns, IR spectroscopy, MAS-NMR ( 1H and 31P) and chemical analysis. The difference between their specific surface area (SSA: 57.46 for HAp and 12.09 m 2/g for FAp), the percentage of carbon measured after treatment with (C 8H 17OPCl 2) and the intensities of IR bands attributed to the grafted moiety suggests that the surface of hydroxyapatite is more reactive than that of fluorapatite. The 31P CP-MAS-NMR spectra of treated fluorapatite show a significant change in isotropic signal due to the protonation and deprotonation of superficial phosphate group. This can be explained by the difference in the nature of inorganic material.

  9. Spectral and thermal studies with anti-fungal aspects of some organotin(IV) complexes with nitrogen and sulphur donor ligands derived from 2-phenylethylamine

    NASA Astrophysics Data System (ADS)

    Singh, Rajeev; Kaushik, N. K.

    2008-11-01

    Some complexes of 2-phenylethyl dithiocarbamate, thiohydrazides and thiodiamines with dibenzyltin(IV) chloride, tribenzyltin(IV) chloride and di( para-chlorobenzyl)tin(IV) dichloride have been synthesized and investigated in 1:2 and 1:1 molar ratio. The dithiocarbamate ligand act as monoanionic bidentate and thiohydrazide, thiodiamines act as neutral bidentate ligand. The synthesized complexes have been characterized by elemental analysis and molecular weight determination studies and their bonding pattern suggested on the basis of electronic, infrared, 1H and 13C NMR spectroscopy. Using thermogravimetric (TG) and differential thermal analysis (DTA) various thermodynamic and kinetic parameters viz. reaction order ( n), apparent activation energy ( Ea), apparent activation entropy ( S#) and heat of reaction (Δ H) have been calculated and correlated with the structural aspects for solid-state decomposition of complexes. The ligands and their tin complexes have also been screened for their fungitoxicity activity against Rhizoctonia solanii and Sclerotium rolfsii and their ED 50 values calculated.

  10. Synthesis and characterization of 8-hydroxyquinoline complexes of tin(IV) and their application in organic light emitting diode.

    PubMed

    Fazaeli, Yousef; Amini, Mostafa M; Najafi, Ezzatollah; Mohajerani, Ezeddin; Janghouri, Mohammad; Jalilian, Amirreza; Ng, Seik Weng

    2012-09-01

    A series of 8-hydroxyquinoline complexes of tin, Q(2)SnCl(2) (Q = 2-methyl-8-hydroxyquinoline, 8-hydroxyquinoline, 5,7-dibromo-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5,7-dichloro-8-hydroxyquinoline and 5-nitro-8-hydroxyquinoline) were prepared by reacting stannous dichloride with 8-hydroxyquinoline and its derivatives. All complexes were characterized by elemental analysis, mass spectrometry and infrared, UV-vis and (1)H NMR spectroscopes. Furthermore, the molecular structure of a representative complex, dichlorido-bis(5-nitro-quinolin-8-olato-2N,O)tin(IV), was determined by single-crystal X-ray diffraction. The photoluminescence (PL) properties of all prepared compounds and electroluminescence (EL) property of a selected complex (Q = 5-chloro-8-hydroxyquinoline) were investigated. The results showed that the emission wavelength can be tuned by electron donating or withdrawing group substituent on 8-hydroxyquinoline. Application of prepared complexes in fabrication of an OLED has been demonstrated.

  11. Spectral and thermal studies with anti-fungal aspects of some organotin(IV) complexes with nitrogen and sulphur donor ligands derived from 2-phenylethylamine.

    PubMed

    Singh, Rajeev; Kaushik, N K

    2008-11-15

    Some complexes of 2-phenylethyl dithiocarbamate, thiohydrazides and thiodiamines with dibenzyltin(IV) chloride, tribenzyltin(IV) chloride and di(para-chlorobenzyl)tin(IV) dichloride have been synthesized and investigated in 1:2 and 1:1 molar ratio. The dithiocarbamate ligand act as monoanionic bidentate and thiohydrazide, thiodiamines act as neutral bidentate ligand. The synthesized complexes have been characterized by elemental analysis and molecular weight determination studies and their bonding pattern suggested on the basis of electronic, infrared, 1H and 13C NMR spectroscopy. Using thermogravimetric (TG) and differential thermal analysis (DTA) various thermodynamic and kinetic parameters viz. reaction order (n), apparent activation energy (Ea), apparent activation entropy (S#) and heat of reaction (DeltaH) have been calculated and correlated with the structural aspects for solid-state decomposition of complexes. The ligands and their tin complexes have also been screened for their fungitoxicity activity against Rhizoctonia solanii and Sclerotium rolfsii and their ED50 values calculated.

  12. Selective Extraction and Recovery of Nd and Dy from Nd-Fe-B Magnet Scrap by Utilizing Molten MgCl2

    NASA Astrophysics Data System (ADS)

    Shirayama, Sakae; Okabe, Toru H.

    2018-06-01

    Fundamental experiments are conducted with the aim of developing an efficient recycling process for rare earth elements (REEs) from neodymium-iron-boron (Nd-Fe-B) permanent magnet scrap. Molten magnesium dichloride (MgCl2) was chosen as an extraction medium, which can selectively chlorinate and extract REEs in magnet alloys. Dysprosium-containing Nd-Fe-B magnet alloy was immersed in molten MgCl2 at 1273 K (1000 °C) for 3 to 12 hours. The results of the experiments clearly show that the REEs in the magnetic alloy were successfully extracted into the molten salt, while the Fe-B alloy remained in a solid form. The extraction ratios of Nd and Dy were at most 87 and 78 mass pct, respectively. After the extraction experiment, excess MgCl2 and Mg were removed by vacuum distillation and the rare earth chlorides were recovered. Thus, the feasibility of this method for efficient recovery of rare earths using molten MgCl2 is demonstrated.

  13. Selective Extraction and Recovery of Nd and Dy from Nd-Fe-B Magnet Scrap by Utilizing Molten MgCl2

    NASA Astrophysics Data System (ADS)

    Shirayama, Sakae; Okabe, Toru H.

    2018-02-01

    Fundamental experiments are conducted with the aim of developing an efficient recycling process for rare earth elements (REEs) from neodymium-iron-boron (Nd-Fe-B) permanent magnet scrap. Molten magnesium dichloride (MgCl2) was chosen as an extraction medium, which can selectively chlorinate and extract REEs in magnet alloys. Dysprosium-containing Nd-Fe-B magnet alloy was immersed in molten MgCl2 at 1273 K (1000 °C) for 3 to 12 hours. The results of the experiments clearly show that the REEs in the magnetic alloy were successfully extracted into the molten salt, while the Fe-B alloy remained in a solid form. The extraction ratios of Nd and Dy were at most 87 and 78 mass pct, respectively. After the extraction experiment, excess MgCl2 and Mg were removed by vacuum distillation and the rare earth chlorides were recovered. Thus, the feasibility of this method for efficient recovery of rare earths using molten MgCl2 is demonstrated.

  14. Microorganisms and methods for degrading plant cell walls and complex hydrocarbons

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

    Polne-Fuller, M.

    1991-09-24

    This patent describes a biologically pure multinucleated marine amoeba having the identifying characteristics of ATCC 40319. The amoeba being capable of digesting algal cell walls and having the further capacity to degrade paraffin, wax, polyethylene, polypropylene, polyvinyl chloride polyvinylidene di-chloride and mixtures thereof.

  15. ACCUMULATION OF DIBUTYLTIN IN HUMAN NATURAL KILLER CELLS

    EPA Science Inventory

    NK cells are a subset of lymphocytes capable of killing tumor cells, virally infected cells and antibody coated cells. Dibutyltin dichloride (DBT) is a butyltin that has been used as a stabilizer in polyvinyl chloride (PVC) plastics and also as a deworming product in poultry. DBT...

  16. A Comparison of Ionic and Covalent Iodine Dihalides: An Integrated Experiment.

    ERIC Educational Resources Information Center

    Woolf, Alfred A.

    1978-01-01

    Compares the preparation and decomposition of potassium dibromoiodate and of phenyl iodine dichloride in a flexible experiment which accustoms the student to handle halogens, to test for halogens in mixtures, and to appreciate the difference between thermodynamic and kinetic control of reactions. (Author/MA)

  17. [CNN]-pincer nickel(II) complexes of N-heterocyclic carbene (NHC): synthesis and catalysis of the Kumada reaction of unactivated C-Cl bonds.

    PubMed

    Sun, Yunqiang; Li, Xiaoyan; Sun, Hongjian

    2014-07-07

    Three novel [CNN]-pincer nickel(ii) complexes with NHC-amine arms were synthesized in three steps. Complex was proven to be an efficient catalyst for the Kumada coupling of aryl chlorides or aryl dichlorides under mild conditions.

  18. 40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

  19. 40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

  20. 40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

  1. Extension of Branches for Orthogonally Fused Molecular Switches

    DTIC Science & Technology

    1991-05-16

    converted to its Grignard reagent . Treatment of the Grignard reagent of 7 with the bromide 6 and (diphenylphosphino)- propanenickel(II) dichloride catalysis...6 afforded the dimer which was deprotonation with LDA and quenched with iodine to give the dimer iodide 8. Treatment of the Grignard reagent of 7 with

  2. IMMUNE RESPONSES IN SPRAGUE-DAWLEY RATS EXPOSED TO DIBUTYLTIN DICHLORIDE IN DRINKING WATER AS ADULTS

    EPA Science Inventory

    Organotins are used commercially as agricultural pesticides, antifouling agents and stabilizers for

    polyvinyl chloride (PVC) pipe. Mono- and di-substituted methyl and butyltins, used in PVC

    pipe production, are of concern as they leach from supply pipes into drinkin...

  3. DEVELOPMENTAL EXPOSURE TO DI-N-BUTYLTIN DICHLORIDE (DBTC): IMMUNOTOXIC AND NEUROTOXIC EVALUATION

    EPA Science Inventory

    Organotins are incorporated as stabilizers in PVC water supply pipe. Particularly when new, mono- and di-substituted methyl- and butyltins leach from the pipe and are thus of regulatory concern to EPA. These contaminants have adverse effects on both the immune and nervous systems...

  4. Serum supplementation modulates the effects of dibutyltin on human natural killer cell function

    EPA Science Inventory

    NK cells are a subset of lymphocytes capable of killing tumor cells, virally infected cells and antibody coated cells. Dibutyltin dichloride (DBT) is an organotin used as a stabilizer in polyvinyl chloride (PVC) plastics and as a deworming product in poultry. DBT may leach from P...

  5. Bonding and Mobility of Alkali Metals in Helicenes.

    PubMed

    Barroso, Jorge; Murillo, Fernando; Martínez-Guajardo, Gerardo; Ortíz-Chi, Filiberto; Pan, Sudip; Fernández-Herrera, María A; Merino, Gabriel

    2018-06-04

    In this work, we analyze the interaction of alkali metal cations with [6]- and [14]helicene and the cation mobility of therein. We found that the distortion of the carbon skeleton is the cause that some of the structures that are local minima for the smallest cations are not energetically stable for K+, Rb+, and Cs+. Also, the most favorable complexes are those where the cation is interacting with two rings forming a metallocene-like structure, except for the largest cation Cs+, where the distortion provoked by the size of the cation desestabilizes the complex. As far as mobility is concerned, the smallest cations, particularly Na+, are the ones that can move most efficiently. In [6]helicene, the mobility is limited by the capture of the cation forming the metallocene-like structure. In larger helicenes, the energy barriers for the cation to move are similar both inside and outside the helix. However, complexes with the cation between two layers are more energetically favored so that the movement will be preferred in that region. The bonding analysis reveals that interactions with no less than 50% of orbitalic contribution are taking place for the series of E+-[6]helicene. Particularly, the complexes of Li+ stand out showing a remarkably orbitalic character bonding (72.5 - 81.6%). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Constrained Geometry Organotitanium Catalysts Supported on Nanosized Silica for Ethylene (co)Polymerization.

    PubMed

    Li, Kuo-Tseng; Wu, Ling-Huey

    2017-05-05

    Supported olefin polymerization catalysts can prevent reactor-fouling problems and produce uniform polymer particles. Constrained geometry complexes (CGCs) have less sterically hindered active sites than bis-cyclopentadienyl metallocene catalysts. In the literature, micrometer-sized silica particles were used for supporting CGC catalysts, which might have strong mass transfer limitations. This study aims to improve the activity of supported CGC catalysts by using nanometer-sized silica. Ti[(C₅Me₄)SiMe₂(N t Bu)]Cl₂, a "constrained-geometry" titanium catalyst, was supported on MAO-treated silicas (nano-sized and micro-sized) by an impregnation method. Ethylene homo-polymerization and co-polymerization with 1-octene were carried out in a temperature range of 80-120 °C using toluene as the solvent. Catalysts prepared and polymers produced were characterized. For both catalysts and for both reactions, the maximum activities occurred at 100 °C, which is significantly higher than that (60 °C) reported before for supported bis-cyclopentadienyl metallocene catalysts containing zirconium, and is lower than that (≥140 °C) used for unsupported Ti[(C₅Me₄)SiMe₂(N t Bu)]Me₂ catalyst. Activities of nano-sized catalyst were 2.6 and 1.6 times those of micro-sized catalyst for homopolymerization and copolymerization, respectively. The former produced polymers with higher crystallinity and melting point than the latter. In addition, copolymer produced with nanosized catalyst contained more 1-octene than that produced with microsized catalyst.

  7. Drosophila muller f elements maintain a distinct set of genomic properties over 40 million years of evolution.

    PubMed

    Leung, Wilson; Shaffer, Christopher D; Reed, Laura K; Smith, Sheryl T; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E J; Machone, Joshua F; Patterson, Seantay D; Price, Amber L; Turner, Bryce A; Robic, Srebrenka; Luippold, Erin K; McCartha, Shannon R; Walji, Tezin A; Walker, Chelsea A; Saville, Kenneth; Abrams, Marita K; Armstrong, Andrew R; Armstrong, William; Bailey, Robert J; Barberi, Chelsea R; Beck, Lauren R; Blaker, Amanda L; Blunden, Christopher E; Brand, Jordan P; Brock, Ethan J; Brooks, Dana W; Brown, Marie; Butzler, Sarah C; Clark, Eric M; Clark, Nicole B; Collins, Ashley A; Cotteleer, Rebecca J; Cullimore, Peterson R; Dawson, Seth G; Docking, Carter T; Dorsett, Sasha L; Dougherty, Grace A; Downey, Kaitlyn A; Drake, Andrew P; Earl, Erica K; Floyd, Trevor G; Forsyth, Joshua D; Foust, Jonathan D; Franchi, Spencer L; Geary, James F; Hanson, Cynthia K; Harding, Taylor S; Harris, Cameron B; Heckman, Jonathan M; Holderness, Heather L; Howey, Nicole A; Jacobs, Dontae A; Jewell, Elizabeth S; Kaisler, Maria; Karaska, Elizabeth A; Kehoe, James L; Koaches, Hannah C; Koehler, Jessica; Koenig, Dana; Kujawski, Alexander J; Kus, Jordan E; Lammers, Jennifer A; Leads, Rachel R; Leatherman, Emily C; Lippert, Rachel N; Messenger, Gregory S; Morrow, Adam T; Newcomb, Victoria; Plasman, Haley J; Potocny, Stephanie J; Powers, Michelle K; Reem, Rachel M; Rennhack, Jonathan P; Reynolds, Katherine R; Reynolds, Lyndsey A; Rhee, Dong K; Rivard, Allyson B; Ronk, Adam J; Rooney, Meghan B; Rubin, Lainey S; Salbert, Luke R; Saluja, Rasleen K; Schauder, Taylor; Schneiter, Allison R; Schulz, Robert W; Smith, Karl E; Spencer, Sarah; Swanson, Bryant R; Tache, Melissa A; Tewilliager, Ashley A; Tilot, Amanda K; VanEck, Eve; Villerot, Matthew M; Vylonis, Megan B; Watson, David T; Wurzler, Juliana A; Wysocki, Lauren M; Yalamanchili, Monica; Zaborowicz, Matthew A; Emerson, Julia A; Ortiz, Carlos; Deuschle, Frederic J; DiLorenzo, Lauren A; Goeller, Katie L; Macchi, Christopher R; Muller, Sarah E; Pasierb, Brittany D; Sable, Joseph E; Tucci, Jessica M; Tynon, Marykathryn; Dunbar, David A; Beken, Levent H; Conturso, Alaina C; Danner, Benjamin L; DeMichele, Gabriella A; Gonzales, Justin A; Hammond, Maureen S; Kelley, Colleen V; Kelly, Elisabeth A; Kulich, Danielle; Mageeney, Catherine M; McCabe, Nikie L; Newman, Alyssa M; Spaeder, Lindsay A; Tumminello, Richard A; Revie, Dennis; Benson, Jonathon M; Cristostomo, Michael C; DaSilva, Paolo A; Harker, Katherine S; Jarrell, Jenifer N; Jimenez, Luis A; Katz, Brandon M; Kennedy, William R; Kolibas, Kimberly S; LeBlanc, Mark T; Nguyen, Trung T; Nicolas, Daniel S; Patao, Melissa D; Patao, Shane M; Rupley, Bryan J; Sessions, Bridget J; Weaver, Jennifer A; Goodman, Anya L; Alvendia, Erica L; Baldassari, Shana M; Brown, Ashley S; Chase, Ian O; Chen, Maida; Chiang, Scott; Cromwell, Avery B; Custer, Ashley F; DiTommaso, Tia M; El-Adaimi, Jad; Goscinski, Nora C; Grove, Ryan A; Gutierrez, Nestor; Harnoto, Raechel S; Hedeen, Heather; Hong, Emily L; Hopkins, Barbara L; Huerta, Vilma F; Khoshabian, Colin; LaForge, Kristin M; Lee, Cassidy T; Lewis, Benjamin M; Lydon, Anniken M; Maniaci, Brian J; Mitchell, Ryan D; Morlock, Elaine V; Morris, William M; Naik, Priyanka; Olson, Nicole C; Osterloh, Jeannette M; Perez, Marcos A; Presley, Jonathan D; Randazzo, Matt J; Regan, Melanie K; Rossi, Franca G; Smith, Melanie A; Soliterman, Eugenia A; Sparks, Ciani J; Tran, Danny L; Wan, Tiffany; Welker, Anne A; Wong, Jeremy N; Sreenivasan, Aparna; Youngblom, Jim; Adams, Andrew; Alldredge, Justin; Bryant, Ashley; Carranza, David; Cifelli, Alyssa; Coulson, Kevin; Debow, Calise; Delacruz, Noelle; Emerson, Charlene; Farrar, Cassandra; Foret, Don; Garibay, Edgar; Gooch, John; Heslop, Michelle; Kaur, Sukhjit; Khan, Ambreen; Kim, Van; Lamb, Travis; Lindbeck, Peter; Lucas, Gabi; Macias, Elizabeth; Martiniuc, Daniela; Mayorga, Lissett; Medina, Joseph; Membreno, Nelson; Messiah, Shady; Neufeld, Lacey; Nguyen, San Francisco; Nichols, Zachary; Odisho, George; Peterson, Daymon; Rodela, Laura; Rodriguez, Priscilla; Rodriguez, Vanessa; Ruiz, Jorge; Sherrill, Will; Silva, Valeria; Sparks, Jeri; Statton, Geeta; Townsend, Ashley; Valdez, Isabel; Waters, Mary; Westphal, Kyle; Winkler, Stacey; Zumkehr, Joannee; DeJong, Randall J; Hoogewerf, Arlene J; Ackerman, Cheri M; Armistead, Isaac O; Baatenburg, Lara; Borr, Matthew J; Brouwer, Lindsay K; Burkhart, Brandon J; Bushhouse, Kelsey T; Cesko, Lejla; Choi, Tiffany Y Y; Cohen, Heather; Damsteegt, Amanda M; Darusz, Jess M; Dauphin, Cory M; Davis, Yelena P; Diekema, Emily J; Drewry, Melissa; Eisen, Michelle E M; Faber, Hayley M; Faber, Katherine J; Feenstra, Elizabeth; Felzer-Kim, Isabella T; Hammond, Brandy L; Hendriksma, Jesse; Herrold, Milton R; Hilbrands, Julia A; Howell, Emily J; Jelgerhuis, Sarah A; Jelsema, Timothy R; Johnson, Benjamin K; Jones, Kelly K; Kim, Anna; Kooienga, Ross D; Menyes, Erika E; Nollet, Eric A; Plescher, Brittany E; Rios, Lindsay; Rose, Jenny L; Schepers, Allison J; Scott, Geoff; Smith, Joshua R; Sterling, Allison M; Tenney, Jenna C; Uitvlugt, Chris; VanDyken, Rachel E; VanderVennen, Marielle; Vue, Samantha; Kokan, Nighat P; Agbley, Kwabea; Boham, Sampson K; Broomfield, Daniel; Chapman, Kayla; Dobbe, Ali; Dobbe, Ian; Harrington, William; Ibrahem, Marwan; Kennedy, Andre; Koplinsky, Chad A; Kubricky, Cassandra; Ladzekpo, Danielle; Pattison, Claire; Ramirez, Roman E; Wande, Lucia; Woehlke, Sarah; Wawersik, Matthew; Kiernan, Elizabeth; Thompson, Jeffrey S; Banker, Roxanne; Bartling, Justina R; Bhatiya, Chinmoy I; Boudoures, Anna L; Christiansen, Lena; Fosselman, Daniel S; French, Kristin M; Gill, Ishwar S; Havill, Jessen T; Johnson, Jaelyn L; Keny, Lauren J; Kerber, John M; Klett, Bethany M; Kufel, Christina N; May, Francis J; Mecoli, Jonathan P; Merry, Callie R; Meyer, Lauren R; Miller, Emily G; Mullen, Gregory J; Palozola, Katherine C; Pfeil, Jacob J; Thomas, Jessica G; Verbofsky, Evan M; Spana, Eric P; Agarwalla, Anant; Chapman, Julia; Chlebina, Ben; Chong, Insun; Falk, I N; Fitzgibbons, John D; Friedman, Harrison; Ighile, Osagie; Kim, Andrew J; Knouse, Kristin A; Kung, Faith; Mammo, Danny; Ng, Chun Leung; Nikam, Vinayak S; Norton, Diana; Pham, Philip; Polk, Jessica W; Prasad, Shreya; Rankin, Helen; Ratliff, Camille D; Scala, Victoria; Schwartz, Nicholas U; Shuen, Jessica A; Xu, Amy; Xu, Thomas Q; Zhang, Yi; Rosenwald, Anne G; Burg, Martin G; Adams, Stephanie J; Baker, Morgan; Botsford, Bobbi; Brinkley, Briana; Brown, Carter; Emiah, Shadie; Enoch, Erica; Gier, Chad; Greenwell, Alyson; Hoogenboom, Lindsay; Matthews, Jordan E; McDonald, Mitchell; Mercer, Amanda; Monsma, Nicholaus; Ostby, Kristine; Ramic, Alen; Shallman, Devon; Simon, Matthew; Spencer, Eric; Tomkins, Trisha; Wendland, Pete; Wylie, Anna; Wolyniak, Michael J; Robertson, Gregory M; Smith, Samuel I; DiAngelo, Justin R; Sassu, Eric D; Bhalla, Satish C; Sharif, Karim A; Choeying, Tenzin; Macias, Jason S; Sanusi, Fareed; Torchon, Karvyn; Bednarski, April E; Alvarez, Consuelo J; Davis, Kristen C; Dunham, Carrie A; Grantham, Alaina J; Hare, Amber N; Schottler, Jennifer; Scott, Zackary W; Kuleck, Gary A; Yu, Nicole S; Kaehler, Marian M; Jipp, Jacob; Overvoorde, Paul J; Shoop, Elizabeth; Cyrankowski, Olivia; Hoover, Betsy; Kusner, Matt; Lin, Devry; Martinov, Tijana; Misch, Jonathan; Salzman, Garrett; Schiedermayer, Holly; Snavely, Michael; Zarrasola, Stephanie; Parrish, Susan; Baker, Atlee; Beckett, Alissa; Belella, Carissa; Bryant, Julie; Conrad, Turner; Fearnow, Adam; Gomez, Carolina; Herbstsomer, Robert A; Hirsch, Sarah; Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques Dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T; Poet, Jeffrey L; Allen, Alica B; Anderson, John E; Barnett, Jason M; Baumgardner, Jordan S; Brown, Adam D; Carney, Jordan E; Chavez, Ramiro A; Christgen, Shelbi L; Christie, Jordan S; Clary, Andrea N; Conn, Michel A; Cooper, Kristen M; Crowley, Matt J; Crowley, Samuel T; Doty, Jennifer S; Dow, Brian A; Edwards, Curtis R; Elder, Darcie D; Fanning, John P; Janssen, Bridget M; Lambright, Anthony K; Lane, Curtiss E; Limle, Austin B; Mazur, Tammy; McCracken, Marly R; McDonough, Alexa M; Melton, Amy D; Minnick, Phillip J; Musick, Adam E; Newhart, William H; Noynaert, Joseph W; Ogden, Bradley J; Sandusky, Michael W; Schmuecker, Samantha M; Shipman, Anna L; Smith, Anna L; Thomsen, Kristen M; Unzicker, Matthew R; Vernon, William B; Winn, Wesley W; Woyski, Dustin S; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J; Aronhalt, Todd; Bellush, James M; Burke, Christa; DeFazio, Steve; Does, Benjamin R; Johnson, Todd D; Keysock, Nicholas; Knudsen, Nelson H; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S; Stagaard, Erica; Starcher, Justin R; Waggoner, Andrew W; Yemelyanova, Anastasia K; Hark, Amy T; Bertolet, Anne; Kuschner, Cyrus E; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E; Smith, Mary A; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S Catherine Silver; Henry, Tyneshia C P; Johnson, Ashlee G; White, Jackie X; Haberman, Adam; Asinof, Sam; Drumm, Kelly; Freeburg, Trip; Safa, Nadia; Schultz, Darrin; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Wellinghoff, Jules; Hoopes, Laura L M; Chau, Kim M; Ward, Alyssa; Regisford, E Gloria C; Augustine, LaJerald; Davis-Reyes, Brionna; Echendu, Vivienne; Hales, Jasmine; Ibarra, Sharon; Johnson, Lauriaun; Ovu, Steven; Braverman, John M; Bahr, Thomas J; Caesar, Nicole M; Campana, Christopher; Cassidy, Daniel W; Cognetti, Peter A; English, Johnathan D; Fadus, Matthew C; Fick, Cameron N; Freda, Philip J; Hennessy, Bryan M; Hockenberger, Kelsey; Jones, Jennifer K; King, Jessica E; Knob, Christopher R; Kraftmann, Karen J; Li, Linghui; Lupey, Lena N; Minniti, Carl J; Minton, Thomas F; Moran, Joseph V; Mudumbi, Krishna; Nordman, Elizabeth C; Puetz, William J; Robinson, Lauren M; Rose, Thomas J; Sweeney, Edward P; Timko, Ashley S; Paetkau, Don W; Eisler, Heather L; Aldrup, Megan E; Bodenberg, Jessica M; Cole, Mara G; Deranek, Kelly M; DeShetler, Megan; Dowd, Rose M; Eckardt, Alexandra K; Ehret, Sharon C; Fese, Jessica; Garrett, Amanda D; Kammrath, Anna; Kappes, Michelle L; Light, Morgan R; Meier, Anne C; O'Rouke, Allison; Perella, Mallory; Ramsey, Kimberley; Ramthun, Jennifer R; Reilly, Mary T; Robinett, Deirdre; Rossi, Nadine L; Schueler, Mary Grace; Shoemaker, Emma; Starkey, Kristin M; Vetor, Ashley; Vrable, Abby; Chandrasekaran, Vidya; Beck, Christopher; Hatfield, Kristen R; Herrick, Douglas A; Khoury, Christopher B; Lea, Charlotte; Louie, Christopher A; Lowell, Shannon M; Reynolds, Thomas J; Schibler, Jeanine; Scoma, Alexandra H; Smith-Gee, Maxwell T; Tuberty, Sarah; Smith, Christopher D; Lopilato, Jane E; Hauke, Jeanette; Roecklein-Canfield, Jennifer A; Corrielus, Maureen; Gilman, Hannah; Intriago, Stephanie; Maffa, Amanda; Rauf, Sabya A; Thistle, Katrina; Trieu, Melissa; Winters, Jenifer; Yang, Bib; Hauser, Charles R; Abusheikh, Tariq; Ashrawi, Yara; Benitez, Pedro; Boudreaux, Lauren R; Bourland, Megan; Chavez, Miranda; Cruz, Samantha; Elliott, GiNell; Farek, Jesse R; Flohr, Sarah; Flores, Amanda H; Friedrichs, Chelsey; Fusco, Zach; Goodwin, Zane; Helmreich, Eric; Kiley, John; Knepper, John Mark; Langner, Christine; Martinez, Megan; Mendoza, Carlos; Naik, Monal; Ochoa, Andrea; Ragland, Nicolas; Raimey, England; Rathore, Sunil; Reza, Evangelina; Sadovsky, Griffin; Seydoux, Marie-Isabelle B; Smith, Jonathan E; Unruh, Anna K; Velasquez, Vicente; Wolski, Matthew W; Gosser, Yuying; Govind, Shubha; Clarke-Medley, Nicole; Guadron, Leslie; Lau, Dawn; Lu, Alvin; Mazzeo, Cheryl; Meghdari, Mariam; Ng, Simon; Pamnani, Brad; Plante, Olivia; Shum, Yuki Kwan Wa; Song, Roy; Johnson, Diana E; Abdelnabi, Mai; Archambault, Alexi; Chamma, Norma; Gaur, Shailly; Hammett, Deborah; Kandahari, Adrese; Khayrullina, Guzal; Kumar, Sonali; Lawrence, Samantha; Madden, Nigel; Mandelbaum, Max; Milnthorp, Heather; Mohini, Shiv; Patel, Roshni; Peacock, Sarah J; Perling, Emily; Quintana, Amber; Rahimi, Michael; Ramirez, Kristen; Singhal, Rishi; Weeks, Corinne; Wong, Tiffany; Gillis, Aubree T; Moore, Zachary D; Savell, Christopher D; Watson, Reece; Mel, Stephanie F; Anilkumar, Arjun A; Bilinski, Paul; Castillo, Rostislav; Closser, Michael; Cruz, Nathalia M; Dai, Tiffany; Garbagnati, Giancarlo F; Horton, Lanor S; Kim, Dongyeon; Lau, Joyce H; Liu, James Z; Mach, Sandy D; Phan, Thu A; Ren, Yi; Stapleton, Kenneth E; Strelitz, Jean M; Sunjed, Ray; Stamm, Joyce; Anderson, Morgan C; Bonifield, Bethany Grace; Coomes, Daniel; Dillman, Adam; Durchholz, Elaine J; Fafara-Thompson, Antoinette E; Gross, Meleah J; Gygi, Amber M; Jackson, Lesley E; Johnson, Amy; Kocsisova, Zuzana; Manghelli, Joshua L; McNeil, Kylie; Murillo, Michael; Naylor, Kierstin L; Neely, Jessica; Ogawa, Emmy E; Rich, Ashley; Rogers, Anna; Spencer, J Devin; Stemler, Kristina M; Throm, Allison A; Van Camp, Matt; Weihbrecht, Katie; Wiles, T Aaron; Williams, Mallory A; Williams, Matthew; Zoll, Kyle; Bailey, Cheryl; Zhou, Leming; Balthaser, Darla M; Bashiri, Azita; Bower, Mindy E; Florian, Kayla A; Ghavam, Nazanin; Greiner-Sosanko, Elizabeth S; Karim, Helmet; Mullen, Victor W; Pelchen, Carly E; Yenerall, Paul M; Zhang, Jiayu; Rubin, Michael R; Arias-Mejias, Suzette M; Bermudez-Capo, Armando G; Bernal-Vega, Gabriela V; Colon-Vazquez, Mariela; Flores-Vazquez, Arelys; Gines-Rosario, Mariela; Llavona-Cartagena, Ivan G; Martinez-Rodriguez, Javier O; Ortiz-Fuentes, Lionel; Perez-Colomba, Eliezer O; Perez-Otero, Joseph; Rivera, Elisandra; Rodriguez-Giron, Luke J; Santiago-Sanabria, Arnaldo J; Senquiz-Gonzalez, Andrea M; delValle, Frank R Soto; Vargas-Franco, Dorianmarie; Velázquez-Soto, Karla I; Zambrana-Burgos, Joan D; Martinez-Cruzado, Juan Carlos; Asencio-Zayas, Lillyann; Babilonia-Figueroa, Kevin; Beauchamp-Pérez, Francis D; Belén-Rodríguez, Juliana; Bracero-Quiñones, Luciann; Burgos-Bula, Andrea P; Collado-Méndez, Xavier A; Colón-Cruz, Luis R; Correa-Muller, Ana I; Crooke-Rosado, Jonathan L; Cruz-García, José M; Defendini-Ávila, Marianna; Delgado-Peraza, Francheska M; Feliciano-Cancela, Alex J; Gónzalez-Pérez, Valerie M; Guiblet, Wilfried; Heredia-Negrón, Aldo; Hernández-Muñiz, Jennifer; Irizarry-González, Lourdes N; Laboy-Corales, Ángel L; Llaurador-Caraballo, Gabriela A; Marín-Maldonado, Frances; Marrero-Llerena, Ulises; Martell-Martínez, Héctor A; Martínez-Traverso, Idaliz M; Medina-Ortega, Kiara N; Méndez-Castellanos, Sonya G; Menéndez-Serrano, Krizia C; Morales-Caraballo, Carol I; Ortiz-DeChoudens, Saryleine; Ortiz-Ortiz, Patricia; Pagán-Torres, Hendrick; Pérez-Afanador, Diana; Quintana-Torres, Enid M; Ramírez-Aponte, Edwin G; Riascos-Cuero, Carolina; Rivera-Llovet, Michelle S; Rivera-Pagán, Ingrid T; Rivera-Vicéns, Ramón E; Robles-Juarbe, Fabiola; Rodríguez-Bonilla, Lorraine; Rodríguez-Echevarría, Brian O; Rodríguez-García, Priscila M; Rodríguez-Laboy, Abneris E; Rodríguez-Santiago, Susana; Rojas-Vargas, Michael L; Rubio-Marrero, Eva N; Santiago-Colón, Albeliz; Santiago-Ortiz, Jorge L; Santos-Ramos, Carlos E; Serrano-González, Joseline; Tamayo-Figueroa, Alina M; Tascón-Peñaranda, Edna P; Torres-Castillo, José L; Valentín-Feliciano, Nelson A; Valentín-Feliciano, Yashira M; Vargas-Barreto, Nadyan M; Vélez-Vázquez, Miguel; Vilanova-Vélez, Luis R; Zambrana-Echevarría, Cristina; MacKinnon, Christy; Chung, Hui-Min; Kay, Chris; Pinto, Anthony; Kopp, Olga R; Burkhardt, Joshua; Harward, Chris; Allen, Robert; Bhat, Pavan; Chang, Jimmy Hsiang-Chun; Chen, York; Chesley, Christopher; Cohn, Dara; DuPuis, David; Fasano, Michael; Fazzio, Nicholas; Gavinski, Katherine; Gebreyesus, Heran; Giarla, Thomas; Gostelow, Marcus; Greenstein, Rachel; Gunasinghe, Hashini; Hanson, Casey; Hay, Amanda; He, Tao Jian; Homa, Katie; Howe, Ruth; Howenstein, Jeff; Huang, Henry; Khatri, Aaditya; Kim, Young Lu; Knowles, Olivia; Kong, Sarah; Krock, Rebecca; Kroll, Matt; Kuhn, Julia; Kwong, Matthew; Lee, Brandon; Lee, Ryan; Levine, Kevin; Li, Yedda; Liu, Bo; Liu, Lucy; Liu, Max; Lousararian, Adam; Ma, Jimmy; Mallya, Allyson; Manchee, Charlie; Marcus, Joseph; McDaniel, Stephen; Miller, Michelle L; Molleston, Jerome M; Diez, Cristina Montero; Ng, Patrick; Ngai, Natalie; Nguyen, Hien; Nylander, Andrew; Pollack, Jason; Rastogi, Suchita; Reddy, Himabindu; Regenold, Nathaniel; Sarezky, Jon; Schultz, Michael; Shim, Jien; Skorupa, Tara; Smith, Kenneth; Spencer, Sarah J; Srikanth, Priya; Stancu, Gabriel; Stein, Andrew P; Strother, Marshall; Sudmeier, Lisa; Sun, Mengyang; Sundaram, Varun; Tazudeen, Noor; Tseng, Alan; Tzeng, Albert; Venkat, Rohit; Venkataram, Sandeep; Waldman, Leah; Wang, Tracy; Yang, Hao; Yu, Jack Y; Zheng, Yin; Preuss, Mary L; Garcia, Angelica; Juergens, Matt; Morris, Robert W; Nagengast, Alexis A; Azarewicz, Julie; Carr, Thomas J; Chichearo, Nicole; Colgan, Mike; Donegan, Megan; Gardner, Bob; Kolba, Nik; Krumm, Janice L; Lytle, Stacey; MacMillian, Laurell; Miller, Mary; Montgomery, Andrew; Moretti, Alysha; Offenbacker, Brittney; Polen, Mike; Toth, John; Woytanowski, John; Kadlec, Lisa; Crawford, Justin; Spratt, Mary L; Adams, Ashley L; Barnard, Brianna K; Cheramie, Martin N; Eime, Anne M; Golden, Kathryn L; Hawkins, Allyson P; Hill, Jessica E; Kampmeier, Jessica A; Kern, Cody D; Magnuson, Emily E; Miller, Ashley R; Morrow, Cody M; Peairs, Julia C; Pickett, Gentry L; Popelka, Sarah A; Scott, Alexis J; Teepe, Emily J; TerMeer, Katie A; Watchinski, Carmen A; Watson, Lucas A; Weber, Rachel E; Woodard, Kate A; Barnard, Daron C; Appiah, Isaac; Giddens, Michelle M; McNeil, Gerard P; Adebayo, Adeola; Bagaeva, Kate; Chinwong, Justina; Dol, Chrystel; George, Eunice; Haltaufderhyde, Kirk; Haye, Joanna; Kaur, Manpreet; Semon, Max; Serjanov, Dmitri; Toorie, Anika; Wilson, Christopher; Riddle, Nicole C; Buhler, Jeremy; Mardis, Elaine R; Elgin, Sarah C R

    2015-03-04

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25-50%) than euchromatic reference regions (3-11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11-27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4-3.6 vs. 8.4-8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu. Copyright © 2015 Leung et al.

  8. Environmental Compliance Assessment and Management Program (ECAMP), South Carolina Supplement

    DTIC Science & Technology

    1994-04-01

    Carbaryl 63252 25.00 Carbon Disulfide 75150 150.00 Carbon Tetrachloride 56235 150.00. Carbonyl Sulfide 463581 12250.00 Catechol 120809 297.00...7.50 Propoxur H4261 2.50 Propylene Dichloride 78875 1750.00 1.2 Propylene Oxide 75569 250.00 Propylenimine (1.2-) 75558 23.35 Pyrethrin 1 121211 25(X

  9. Environmental Compliance Assessment System (ECAS). South Carolina Supplement. U.S. Army

    DTIC Science & Technology

    1994-04-01

    Cyanamide. 156627 2.50 Captan 133062 25.00 Carbaryl 63252 25.00 Carbon Disulfide 75150 150.00 Carbon Tetrachloride 56235 150.00. Carbonyl Sulfide...1120714 + b-Propiolactone 57578 7.50 Propoxur 114261 2.50 Propylene Dichloride 78875 1750.00 1,2 Propylene Oxide 75569 250.00 Propylenimine (1,2

  10. Niosh analytical methods for Set G

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

    Not Available

    1976-12-01

    Industrial Hygiene sampling and analytical monitoring methods validated under the joint NIOSH/OSHA Standards Completion Program for Set G are contained herein. Monitoring methods for the following compounds are included: butadiene, heptane, ketene, methyl cyclohexane, octachloronaphthalene, pentachloronaphthalene, petroleum distillates, propylene dichloride, turpentine, dioxane, hexane, LPG, naphtha(coal tar), octane, pentane, propane, and stoddard solvent.

  11. IMMUNE FUNCTION IS NOT IMPAIRED IN SPRAGUE-DAWLEY RATS EXPOSED TO DIMETHYLTIN DICHLORIDE (DMTC) DURING DEVELOPMENT OR ADULTHOOD

    EPA Science Inventory

    Abstract

    Organotins are used commercially as pesticides, antifouling agents and stabilizers for polyvinyl chloride (PVC) pipe. Mono- and di-substituted butyltins, used in PVC pipe production, are of concern to the U.S. EPA because they leach from supply pipes into drinkin...

  12. Sequestering ability of butylated hydroxytoluene, propyl gallate, resveratrol, and vitamins C and E against ABTS, DPPH, and hydroxyl free radicals in chemical and biological systems.

    PubMed

    Soares, Daniele G; Andreazza, Ana C; Salvador, Mirian

    2003-02-12

    The antioxidant capacity of butylated hydroxytoluene (BHT; 2,6-di-tert-butyl-p-cresol), propyl gallate (3,4,5-trihydroxybenzoic acid n-propyl ester), resveratrol (trans-3,4',5-trihydroxystilbene), and vitamins C (l-ascorbic acid) and E [(+)-alpha-tocopherol] was studied in chemical and biological systems. The chemical assays evaluated the capacity of these antioxidants to sequester 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.) and 1,1 diphenyl-2-picrylhydrazyl (DPPH.). A new colorimetric method to determine hydroxyl radical scavenging is also described. The biological tests use the eucaryotic cells of Saccharomyces cerevisiae treated with the antioxidants in the presence of the stressing agents apomorphine, hydrogen peroxide, and paraquat dichloride (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). The results in chemical systems showed that all of the antioxidants were able to significantly inhibit the oxidation of beta-carotene by hydroxyl free radicals. The assays in yeast showed that the antioxidant activity of the tested compounds depended on the stressing agent used and the mechanism of action of the antioxidant.

  13. Analysis of ToxCast data for food-relevant compounds by ...

    EPA Pesticide Factsheets

    The ToxCast program has generated a wealth of in vitro high throughput screening data, and best approaches for the interpretation and use of these data remain undetermined. We present case studies comparing the ToxCast and in vivo toxicity data for two food contact substances using the RISK21 approach. Available exposure data, toxicity data, and model predictions were analyzed for sodium pyrithione and dibutyltin dichloride. In-vitro to in-vivo extrapolation (IVIVE) was performed to determine oral equivalent doses (OEDs) for the ToxCast data bioactivity. For sodium pyrithione, calculated OEDs corresponded to doses that demonstrated toxicity in animal studies. For dibutyltin dichloride, calculated OEDs were below the doses that demonstrated toxicity in animals, but this was confounded by the conservative estimates used in the IVIVE calculations. These studies highlight the potential of the ToxCast approach while also indicating areas where additional data or predictive tools are needed. We present case studies comparing the ToxCast and in vivo toxicity data for two food contact substances using the RISK21 approach.

  14. Targeted α-Particle Therapy of Bone Metastases in Prostate Cancer

    PubMed Central

    Jadvar, Hossein; Quinn, David I.

    2013-01-01

    Medical oncology is moving toward personalized and precision treatments. This evolution is spearheaded by ongoing discoveries on the fundamental machinery that controls tumor and hosts microenvironment biological behavior. α-Particles with their high energy and short range had long been recognized as potentially useful in the treatment of cancer. More than a century after the discovery of radium by the Curies, 223Ra dichloride is now available in the expanding armamentarium of therapies for metastatic castration-resistant prostate cancer. This advance occurs in the context of several other novel therapeutics in advanced prostate cancer that include more effective androgen receptor pathway inhibition, better chemotherapy, and immunotherapy. We present a concise review on the therapeutic use of 223Ra dichloride in this clinically important setting including excerpts on the radium history, physical properties, the alpharadin in symptomatic prostate cancer clinical trial, and practical information on its use in the clinic. It is anticipated that, with the current emergence of 223Ra as a viable form of therapy, interest in and use of α-particle therapy in the management of cancer will grow. PMID:24212441

  15. Metallocene-Containing Homopolymers and Heterobimetallic Block Copolymers via Photoinduced RAFT Polymerization

    PubMed Central

    Yang, Peng; Pageni, Parasmani; Kabir, Mohammad Pabel; Zhu, Tianyu; Tang, Chuanbing

    2017-01-01

    We report the synthesis of cationic cobaltocenium and neutral ferrocene containing homopolymers mediated by photoinduced reversible addition-fragmentation chain transfer (RAFT) polymerization with a photocatalyst fac-[Ir(ppy)3]. The homopolymers were further used as macromolecular chain transfer agents to synthesize diblock copolymers via chain extension. Controlled/“living” feature of photoinduced RAFT polymerization was confirmed by kinetic studies even without prior deoxygenation. A light switch between ON and OFF provided a spatiotemporal control of polymerization. PMID:29276651

  16. The Role of Solvent Reorganization Dynamics in Electron-Transfer Processes. Theory-Experiment Comparisons for Electrochemical and Homogeneous Electron Exchange Involving Metallocene Redox Couples

    DTIC Science & Technology

    1985-08-01

    Kodak) by crystallization from acetone; it was recrystallized twice from ethanol and dried in a vacuum oven. Tetraethylamonium perchlorate (TEAP) (G...the electrooxidation of in(Cp’) 2 , which yielded significantly smaller reverse (cathodic) currents in the most strongly coordinating solvents (DMX...DM50) at slower scan rates (< 0.5 V sec-1). Nevertheless, satisfactory a.c. polarograms were obtained for each of these system=. 5 4 Temperature

  17. Ansa-Complexes of [Mn(η(5) -C5 H5 )(η(6) -C6 H6 )]: Preparation, Characterization, and Reactivity of [n]Manganoarenophanes (n=1, 2, 3).

    PubMed

    Braunschweig, Holger; Damme, Alexander; Dück, Klaus; Fuß, Marco; Hörl, Christian; Kramer, Thomas; Krummenacher, Ivo; Kupfer, Thomas; Paprocki, Valerie; Schneider, Christoph

    2015-10-12

    We report the synthesis of [n]manganoarenophanes (n=1, 2) featuring boron, silicon, germanium, and tin as ansa-bridging elements. Their preparation was achieved by salt-elimination reactions of the dilithiated precursor [Mn(η(5) -C5 H4 Li)(η(6) -C6 H5 Li)]⋅pmdta (pmdta=N,N,N',N',N''-pentamethyldiethylenetriamine) with corresponding element dichlorides. Besides characterization by multinuclear NMR spectroscopy and elemental analysis, the identity of two single-atom-bridged derivatives, [Mn(η(5) -C5 H4 )(η(6) -C6 H5 )SntBu2 ] and [Mn(η(5) -C5 H4 )(η(6) -C6 H5 )SiPh2 ], could also be determined by X-ray structural analysis. We investigated for the first time the reactivity of these ansa-cyclopentadienyl-benzene manganese compounds. The reaction of the distannyl-bridged complex [Mn(η(5) -C5 H4 )(η(6) -C6 H5 )Sn2 tBu4 ] with elemental sulfur was shown to proceed through the expected oxidative addition of the Sn-Sn bond to give a triatomic ansa-bridge. The investigation of the ring-opening polymerization (ROP) capability of [Mn(η(5) -C5 H4 )(η(6) -C6 H5 )SntBu2 ] with [Pt(PEt3 )3 ] showed that an unexpected, unselective insertion into the Cipso -Sn bonds of [Mn(η(5) -C5 H4 )(η(6) -C6 H5 )SntBu2 ] had occurred. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Drosophila Muller F Elements Maintain a Distinct Set of Genomic Properties Over 40 Million Years of Evolution

    PubMed Central

    Leung, Wilson; Shaffer, Christopher D.; Reed, Laura K.; Smith, Sheryl T.; Barshop, William; Dirkes, William; Dothager, Matthew; Lee, Paul; Wong, Jeannette; Xiong, David; Yuan, Han; Bedard, James E. 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Johnson, Christen; Jones, Melissa; Kabaso, Rita; Lemmon, Eric; Vieira, Carolina Marques dos Santos; McFarland, Darryl; McLaughlin, Christopher; Morgan, Abbie; Musokotwane, Sepo; Neutzling, William; Nietmann, Jana; Paluskievicz, Christina; Penn, Jessica; Peoples, Emily; Pozmanter, Caitlin; Reed, Emily; Rigby, Nichole; Schmidt, Lasse; Shelton, Micah; Shuford, Rebecca; Tirasawasdichai, Tiara; Undem, Blair; Urick, Damian; Vondy, Kayla; Yarrington, Bryan; Eckdahl, Todd T.; Poet, Jeffrey L.; Allen, Alica B.; Anderson, John E.; Barnett, Jason M.; Baumgardner, Jordan S.; Brown, Adam D.; Carney, Jordan E.; Chavez, Ramiro A.; Christgen, Shelbi L.; Christie, Jordan S.; Clary, Andrea N.; Conn, Michel A.; Cooper, Kristen M.; Crowley, Matt J.; Crowley, Samuel T.; Doty, Jennifer S.; Dow, Brian A.; Edwards, Curtis R.; Elder, Darcie D.; Fanning, John P.; Janssen, Bridget M.; Lambright, Anthony K.; Lane, Curtiss E.; Limle, Austin B.; Mazur, Tammy; McCracken, Marly R.; McDonough, Alexa M.; Melton, Amy D.; Minnick, Phillip J.; Musick, Adam E.; Newhart, William H.; Noynaert, Joseph W.; Ogden, Bradley J.; Sandusky, Michael W.; Schmuecker, Samantha M.; Shipman, Anna L.; Smith, Anna L.; Thomsen, Kristen M.; Unzicker, Matthew R.; Vernon, William B.; Winn, Wesley W.; Woyski, Dustin S.; Zhu, Xiao; Du, Chunguang; Ament, Caitlin; Aso, Soham; Bisogno, Laura Simone; Caronna, Jason; Fefelova, Nadezhda; Lopez, Lenin; Malkowitz, Lorraine; Marra, Jonathan; Menillo, Daniella; Obiorah, Ifeanyi; Onsarigo, Eric Nyabeta; Primus, Shekerah; Soos, Mahdi; Tare, Archana; Zidan, Ameer; Jones, Christopher J.; Aronhalt, Todd; Bellush, James M.; Burke, Christa; DeFazio, Steve; Does, Benjamin R.; Johnson, Todd D.; Keysock, Nicholas; Knudsen, Nelson H.; Messler, James; Myirski, Kevin; Rekai, Jade Lea; Rempe, Ryan Michael; Salgado, Michael S.; Stagaard, Erica; Starcher, Justin R.; Waggoner, Andrew W.; Yemelyanova, Anastasia K.; Hark, Amy T.; Bertolet, Anne; Kuschner, Cyrus E.; Parry, Kesley; Quach, Michael; Shantzer, Lindsey; Shaw, Mary E.; Smith, Mary A.; Glenn, Omolara; Mason, Portia; Williams, Charlotte; Key, S. 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    2015-01-01

    The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu. PMID:25740935

  19. A two-generation inhalation reproductive toxicity study upon the exposure to manganese chloride.

    PubMed

    McGough, Doreen; Jardine, Lynne

    2017-01-01

    A number of published studies have suggested that high levels of exposure to manganese, especially those found in occupational settings, can adversely affect the reproductive system. The objective of this study was therefore to investigate if these findings can be replicated using the Sprague Dawley rat and, if so, to identify those parts of the reproductive system are more susceptible. Male and female rats were exposed to manganese dichloride (MnCl 2 ) via inhalation at concentrations of 0 (air-control); 5, 10 and 20μg/L air over 10 weeks (F0) and over 11 weeks (F1) prior to mating, and then throughout mating, gestation and lactation until termination after the F1 and F2 generation had reached Day 21 of lactation respectively. Animals were monitored for clinical signs of toxicity and for effects on body weight, food consumption, effects on the entire reproductive system including maternal care. The offspring were monitored for survival and growth up to weaning. Blood samples were taken from all adult animals for bioanalytical of manganese analysis prior to dosing, prior to mating and prior to weaning/necropsy. There were no deaths related to treatment, though respiratory tract effects were observed in F0 animals in the mid and high dose animals. Body weight and food consumption were affected at high dose in both generation. There were no treatment-related effects on the oestrous cycles, mating performance, sexual maturity, fertility or duration of gestation or litter size, the sperm motility, count of morphology (sperm) or the ovary follicle scoring in either generation. The No Observed Effect Level (NOEL) for reproductive performance was considered to be the target dose level of 20μg/L. Based on these findings, manganese chloride could not be considered a reprotoxicant under these conditions of exposure. Therefore, soluble and insoluble forms of inorganic manganese compounds by extrapolation cannot be considered as reprotoxicants. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. The National Shipbuilding Research Program. Historical Overview of Efforts to Reduce VOC Emissions Through Coating Reformulations and Analysis of VOC vs HAP Content in Marine Coatings

    DTIC Science & Technology

    1995-05-01

    79118 532274 108907 510156 67663 107302 126998 1319773 95287 108394 106445 1,3-Butadiene Calcium Cyanamide Caprolactam Captan Carbaryl Carbon disulfide...96093 1746016 79345 127184 7550450 108883 95807 584849 95534 8001352 120821 79005 79016 Propionaldehyde Propoxur (Baygon) Propylene dichloride (1,2

  1. DEVELOPMENTAL EXPOSURE TO 1.0 OR 2.5 MG/KG DIBUTYLTIN DICHLORIDE DOES NOT IMPAIR IMMUNE FUNCTION IN SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    Organotins are used commercially as pesticides, antifouling agents and stabilizers for polyvinyl chloride (PVC) pipe. Mono- and di-substituted methyl and butyltins, used in PVC pipe production, are of concern to the U.S. EPA as they leach from supply pipes into drinking water an...

  2. Unit-dose assay of tropine alkaloids and their synthetic analogs.

    PubMed

    Gomaa, C; Taha, A

    1975-08-01

    A charge-transfer spectrophotometric method was developed for unit-dose assay of the tropine alkaloids and some of their synthetic analogs. The high molar absorptivities of the charge-transfer bands of the alkaloids with iodine in ethylene dichloride resulted in improved recoveries and good precision, particularly at the low dose levels of pediatric and hypodermic tablets.

  3. 2. Photocopy of photograph, U.S. Army, ca. 1943 (original print ...

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

    2. Photocopy of photograph, U.S. Army, ca. 1943 (original print located at Rocky Mountain Arsenal, Commerce City, Colorado). R.M.A. - 411-412 - S.M. MFG. & STG. - Rocky Mountain Arsenal, Sulfur Monochloride & Dichloride Manufacturing, 1003 feet South of December Seventh Avenue; 412 feet East of D Street, Commerce City, Adams County, CO

  4. 40 CFR Table 6 to Subpart Jj of... - VHAP of Potential Concern

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Formaldehyde 0.2 101144 4,4′-Methylene bis(2-chloroaniline) 0.02 107131 Acrylonitrile 0.03 106934 Ethylene... Chlorobenzilate 0.04 62737 Dichlorvos 0.02 75014 Vinyl chloride 0.02 75218 Ethylene oxide 0.09 96457 Ethylene... 51796 Ethyl carbamate (Urethane) 0.08 107062 Ethylene dichloride (1,2-Dichloroethane) 0.08 78875...

  5. Coordination Polymers Containing 1,3-Phenylenebis-((1H-1,2,4-triazol-1-yl)methanone) Ligand: Synthesis and ε-Caprolactone Polymerization Behavior.

    PubMed

    Bello-Vieda, Nestor J; Murcia, Ricardo A; Muñoz-Castro, Alvaro; Macías, Mario A; Hurtado, John J

    2017-11-10

    The reaction of isophthaloyl dichloride with 1 H -1,2,4-triazole afforded the new ligand 1,3-phenylenebis(1,2,4-triazole-1-yl)methanone ( 1 ). A series of Co(II), Cu(II), Zn(II) and Ni(II) complexes were synthesized using 1 and then characterized by melting point analysis, elemental analysis, theoretical calculations, thermogravimetric analysis, X-ray powder diffraction, nuclear magnetic resonance, infrared and Raman spectroscopy. Experimental and computational studies predict the formation of coordination polymers (CPs). The cobalt and copper CPs and zinc(II) complex were found to be good initiators for the ring-opening polymerization of ε-caprolactone (CL) under solvent-free conditions. ¹H-NMR analysis showed that the obtained polymers of CL were mainly linear and had terminal hydroxymethylene groups. Differential scanning calorimetry showed that the obtained polycaprolactones had high crystallinity, and TGA showed that they had decomposition temperatures above 400 °C. These results provide insight and guidance for the design of metal complexes with potential applications in the polymerization of CL.

  6. Fertility Inhibitor Heterobimetallic Complexes of Platinum(II) and Palladium(II): Synthetic, Spectroscopic and Antimicrobial Aspects

    PubMed Central

    Sharma, Kripa; Joshi, S. C.

    2000-01-01

    Synthetic, spectroscopic and antimicrobial aspects of some fertility inhibitor heterobimetallic complexes have been carried out. These heterobimetallic chelates [M(C5H5N3)2M2'(R)4]Cl2 (M = Pd or Pt and M' = Si, Sn, Ti and Zr) have been successfully synthesinzed via the reaction of M(C5H7N3)2Cl2 with group four or fourteen dichlorides in 1:2 stoichiometric proportions. The products were characterized by elemental analyses, molecular weight determinations, magnetic susceptibility measurements, conductance, and IR multinuclear NMR and electronic spectral studies. A square planar geometry has been suggested for all the complexes with the help of spectral data. Conductivity data strongly suggest that chlorine atoms are ionic in nature due to which complexes behave as electrolytes. All the complexes have been evaluated for their antmicrobial effects on different species of pathogenic fungi and bacteria. The testicular sperm density, testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemical parameters of reproductive organs have been examined and discussed. PMID:18475932

  7. Homogeneous catalysts for stereoregular olefin polymerization

    DOEpatents

    Marks, T.J.; Eisen, M.S.; Giardello, M.A.

    1995-10-03

    The synthesis, and use as precatalysts of chiral organozirconium complexes for olefin polymerization are disclosed, having the structure (C{sub 5}R{prime}{sub 4{minus}x}R*{sub x})A(C{sub 5}R{double_prime}{sub 4{minus}y}R{double_prime}{prime}{sub y})MQ{sub p}, where x and y represent the number of unsubstituted locations on the cyclopentadienyl ring; R{prime}, R{double_prime}, R{double_prime}{prime}, and R* represent substituted and unsubstituted alkyl groups having 1--30 carbon atoms and R* is a chiral ligand; A is a fragment containing a Group 13, 14, 15, or 16 element of the Periodic Table; M is a Group 3, 4, or 5 metal of the Periodic Table; and Q is a hydrocarbyl radical, or halogen radical, with 3{>=}p{>=}0. Related complexes may be prepared by alkylation of the corresponding dichlorides. In the presence of methylalumoxane or triarylborane cocatalysts, these complexes form ``cation-like`` species which are highly active for olefin polymerization. In combination with a Lewis acid cocatalyst, propylene or other {alpha}-olefin polymerization can be effected with very high efficiency and isospecificity. 1 fig.

  8. Homogeneous catalysts for stereoregular olefin polymerization

    DOEpatents

    Marks, T.J.; Eisen, M.S.; Giardello, M.A.

    1994-07-19

    The synthesis, and use as precatalysts of chiral organozirconium complexes for olefin polymerization are disclosed, having the structure (C[sub 5]R[prime][sub 4[minus]x]R*[sub x])-A-(C[sub 5]R[double prime][sub 4[minus]y]R[prime][double prime][sub y])-M-Q[sub p], where x and y represent the number of unsubstituted locations on the cyclopentadienyl ring; R[prime], R[double prime], R[prime][double prime], and R* represent substituted and unsubstituted alkyl groups having 1--30 carbon atoms and R* is a chiral ligand; A is a fragment containing a Group 13, 14, 15, or 16 element of the Periodic Table; M is a Group 3, 4, or 5 metal of the Periodic Table; and Q is a hydrocarbyl radical, or halogen radical, with 3 [<=] p [<=] 0. Related complexes may be prepared by alkylation of the corresponding dichlorides. In the presence of methylalumoxane or triarylborane cocatalysts, these complexes form cation-like'' species which are highly active for olefin polymerization. In combination with a Lewis acid cocatalyst, propylene or other [alpha]-olefin polymerization can be effected with very high efficiency and isospecificity. 1 fig.

  9. Synthesis and antimicrobial activity of 1-benzhydryl-sulfonyl-4-(3-(piperidin-4-yl) propyl)piperidine derivatives against pathogens of Lycopersicon esculentum: a structure-activity evaluation study.

    PubMed

    Vinaya, K; Kavitha, R; Ananda Kumar, C S; Benaka Prasad, S B; Chandrappa, S; Deepak, S A; Nanjunda Swamy, S; Umesha, S; Rangappa, K S

    2009-01-01

    Several 1-benzhydryl-sulfonyl-4-(3-(piperidin-4-yl)propyl)piperidine derivatives 8(a-j) were prepared by the treatment of substituted benzhydryl chlorides with 4-(3-(piperidin-4-yl)propyl)piperidine followed by N-sulfonation with sulfonyl chlorides in the presence of dry methylene dichloride and triethyl amine. The synthesized compounds were characterized by (1)H-NMR, IR, and elemental analysis. All the synthesized compounds were evaluated in vitro for their efficacy as antimicrobial agents by artificial inoculation technique against standard strains of two important bacterial viz., Xanthomonas axonopodis pv. vesicatoria and Ralstonia solanacearum as well as and two fungal pathogens namely Alternaria solani and Fusarium solani of tomato plants. We have briefly investigated the structure-activity relation studies and reveal that the nature of substitutions on benzhydryl ring and sulfonamide ring influences the antibacterial activity. Among the synthesized new compounds 8b, 8d, 8g, 8h, 8i, and 8j were showed significant potent antimicrobial activities compared to the standard drugs chloramphenicol, mancozeb.

  10. Physical properties of superbulky lanthanide metallocenes: synthesis and extraordinary luminescence of [Eu(II)(Cp(BIG))2] (Cp(BIG) = (4-nBu-C6H4)5-cyclopentadienyl).

    PubMed

    Harder, Sjoerd; Naglav, Dominik; Ruspic, Christian; Wickleder, Claudia; Adlung, Matthias; Hermes, Wilfried; Eul, Matthias; Pöttgen, Rainer; Rego, Daniel B; Poineau, Frederic; Czerwinski, Kenneth R; Herber, Rolfe H; Nowik, Israel

    2013-09-09

    The superbulky deca-aryleuropocene [Eu(Cp(BIG))2], Cp(BIG) = (4-nBu-C6H4)5-cyclopentadienyl, was prepared by reaction of [Eu(dmat)2(thf)2], DMAT = 2-Me2N-α-Me3Si-benzyl, with two equivalents of Cp(BIG)H. Recrystallizyation from cold hexane gave the product with a surprisingly bright and efficient orange emission (45% quantum yield). The crystal structure is isomorphic to those of [M(Cp(BIG))2] (M = Sm, Yb, Ca, Ba) and shows the typical distortions that arise from Cp(BIG)⋅⋅⋅Cp(BIG) attraction as well as excessively large displacement parameter for the heavy Eu atom (U(eq) = 0.075). In order to gain information on the true oxidation state of the central metal in superbulky metallocenes [M(Cp(BIG))2] (M = Sm, Eu, Yb), several physical analyses have been applied. Temperature-dependent magnetic susceptibility data of [Yb(Cp(BIG))2] show diamagnetism, indicating stable divalent ytterbium. Temperature-dependent (151)Eu Mössbauer effect spectroscopic examination of [Eu(Cp(BIG))2] was examined over the temperature range 93-215 K and the hyperfine and dynamical properties of the Eu(II) species are discussed in detail. The mean square amplitude of vibration of the Eu atom as a function of temperature was determined and compared to the value extracted from the single-crystal X-ray data at 203 K. The large difference in these two values was ascribed to the presence of static disorder and/or the presence of low-frequency torsional and librational modes in [Eu(Cp(BIG))2]. X-ray absorbance near edge spectroscopy (XANES) showed that all three [Ln(Cp(BIG))2] (Ln = Sm, Eu, Yb) compounds are divalent. The XANES white-line spectra are at 8.3, 7.3, and 7.8 eV, for Sm, Eu, and Yb, respectively, lower than the Ln2O3 standards. No XANES temperature dependence was found from room temperature to 100 K. XANES also showed that the [Ln(Cp(BIG))2] complexes had less trivalent impurity than a [EuI2(thf)x] standard. The complex [Eu(Cp(BIG))2] shows already at room temperature strong orange photoluminescence (quantum yield: 45 %): excitation at 412 nm (24,270 cm(-1)) gives a symmetrical single band in the emission spectrum at 606 nm (νmax =16495 cm(-1), FWHM: 2090 cm(-1), Stokes-shift: 2140 cm(-1)), which is assigned to a 4f(6)5d(1) → 4f(7) transition of Eu(II). These remarkable values compare well to those for Eu(II)-doped ionic host lattices and are likely caused by the rigidity of the [Eu(Cp(BIG))2] complex. Sharp emission signals, typical for Eu(III), are not visible. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Electrochemistry in supercritical fluids

    PubMed Central

    Branch, Jack A.; Bartlett, Philip N.

    2015-01-01

    A wide range of supercritical fluids (SCFs) have been studied as solvents for electrochemistry with carbon dioxide and hydrofluorocarbons (HFCs) being the most extensively studied. Recent advances have shown that it is possible to get well-resolved voltammetry in SCFs by suitable choice of the conditions and the electrolyte. In this review, we discuss the voltammetry obtained in these systems, studies of the double-layer capacitance, work on the electrodeposition of metals into high aspect ratio nanopores and the use of metallocenes as redox probes and standards in both supercritical carbon dioxide–acetonitrile and supercritical HFCs. PMID:26574527

  12. Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

    PubMed Central

    Heimgartner, Heinz

    2017-01-01

    The scope of applications of dialkyl dicyanofumarates and maleates as highly functionalized electron-deficient dipolarophiles, dienophiles and Michael acceptors is summarized. The importance for the studies on reaction mechanisms of cycloadditions is demonstrated. Multistep reactions with 1,2-diamines and β-aminoalcohols leading to diverse five- and six-membered heterocycles are discussed. Applications of dialkyl dicyanofumarates as oxidizing agents in the syntheses of disulfides and diselenides are described. The reactions with metallocenes leading to charge-transfer complexes with magnetic properties are also presented. PMID:29114328

  13. Redox polymer electrodes for advanced batteries

    DOEpatents

    Gregg, Brian A.; Taylor, A. Michael

    1998-01-01

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene.

  14. Redox polymer electrodes for advanced batteries

    DOEpatents

    Gregg, B.A.; Taylor, A.M.

    1998-11-24

    Advanced batteries having a long cycle lifetime are provided. More specifically, the present invention relates to electrodes made from redox polymer films and batteries in which either the positive electrode, the negative electrode, or both, comprise redox polymers. Suitable redox polymers for this purpose include pyridyl or polypyridyl complexes of transition metals like iron, ruthenium, osmium, chromium, tungsten and nickel; porphyrins (either free base or metallo derivatives); phthalocyanines (either free base or metallo derivatives); metal complexes of cyclams, such as tetraazacyclotetradecane; metal complexes of crown ethers and metallocenes such as ferrocene, cobaltocene and ruthenocene. 2 figs.

  15. Reaction kinetics and product distributions in photoelectrochemical cells

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

    Koval, C.A.

    1992-01-01

    Hot electron reaction studies at p-InP/CH[sub 3]CN interface revealed essential/desirable features for redox systems used to investigate hot carriers in photoelectrocehmical cells. Reduction of dibromoethylbenzene (DBEB) in presence of metallocene couples is being studied using rotating rink disk electrodes of n-and p-InP disks and Pt rings. At highly doped p-InP electrodes, reduction of DBEB can be very efficient (>30%). A minielectrochemical cell was used to investigate electron transfer at nonilluminated n-WSe[sub 2]/dimethylferrocene[sup +/0] interfaces.

  16. 40 CFR 61.65 - Emission standard for ethylene dichloride, vinyl chloride and polyvinyl chloride plants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... basis and analyzes the samples with gas chromatography or, if the owner or operator assumes that all... concentration of vinyl chloride in the exhaust gases does not exceed 10 ppm (average for 3-hour period), or... chloride in the exhaust gases does not exceed 10 ppm (average for 3-hour period), or equivalent as provided...

  17. 21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-octyl)tin S,S′-bis(isooctylmercaptoacetate) is an octyltin chemical having 15.1 to 16.4 percent by weight of tin (Sn) and having 8.1 to 8.9 percent by weight of mercapto sulfur. It is made from di(n-octyl)tin dichloride or di(n-octyl)tin oxide. The isooctyl radical in the mercaptoacetate is derived from...

  18. HIGH TEMPERATURE POLAMINE RESINS.

    DTIC Science & Technology

    A literature search was conducted to investigate work done with aromatic amine-organic chloride reactions and organo- sodium amide preparations from...synthesized by the diamine/dichloride route. Extensive investigations of polyamine synthesis from sodium salts of amides and amines, and chlorides were...conducted. Apparently successful methods were found for preparing sodium derivatives of amides and amines from both solid sodium amide and sodium /ammonia

  19. 75 FR 63827 - Integrated Risk Information System (IRIS); Request for Chemical Substance Nominations for 2011...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-18

    ........... 156-60-5 1,4-dioxane (oral) 123-91-1 ethylene glycol monobutyl ether 111-76-2 (EGBE...-dichlorobenzene 106-46-7 1,2-dichloroethane (ethylene 107-06-2 dichloride). dichloromethane (methylene 75-09-2... 131-18-0 ethanol 64-17-5 ethyl tertiary butyl ether (ETBE). 637-92-3 ethylbenzene 100-41-4 ethylene...

  20. 40 CFR 60.707 - Chemicals affected by subpart RRR.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 123-42-2 1,4-Dichlorobutene 110-57-6 3,4-Dichloro-1-butene 64037-54-3 Dichlorodifluoromethane 75-71-8... Ethyl chloride 75-00-3 Ethylene 74-85-1 Ethylene dibromide 106-93-4 Ethylene dichloride 107-06-2...-7 (2-Ethylhexyl) amine 104-75-6 6-Ethyl-1,2,3,4-tetrahydro 9,10-anthracenedione 15547-17-8...

  1. Ac conductivity and dielectric properties of bulk tin phthalocyanine dichloride (SnPcCl 2)

    NASA Astrophysics Data System (ADS)

    El-Nahass, M. M.; Farid, A. M.; Abd El-Rahman, K. F.; Ali, H. A. M.

    2008-07-01

    The ac conductivity, σac( ω), has been measured for bulk tin phthalocyanine dichloride (SnPcCl 2) in the form of compressed pellet with evaporated ohmic Au electrodes in a temperature range 303-403 K. Ac conductivity, σac( ω), is found to vary as ωs in the frequency range 42 Hz-5×10 6 Hz. At low range of frequency, s<1 and it decreases with the increase in temperature indicating a dominant hopping process. At high range of frequency, s is found to be equal to ≈1.09 and is temperature independent. The dielectric constant, ε1, and dialectic loss, ε2, have been determined for bulk SnPcCl 2. Both ε1 and ε2 decrease with the increase in frequency and increase with the increase in temperature. The Cole-Cole types have been used to determine some parameters such as; the macroscopic relaxation time ( τo), the molecular relaxation time ( τ), the activation energy for relaxation ( Eo) and the distribution parameter ( α). The temperature dependence of τ is expressed by a thermally activated process with the activation energy of 0.299 eV.

  2. Stochastic simulation of radium-223 dichloride therapy at the sub-cellular level

    NASA Astrophysics Data System (ADS)

    Gholami, Y.; Zhu, X.; Fulton, R.; Meikle, S.; El-Fakhri, G.; Kuncic, Z.

    2015-08-01

    Radium-223 dichloride (223Ra) is an alpha particle emitter and a natural bone-seeking radionuclide that is currently used for treating osteoblastic bone metastases associated with prostate cancer. The stochastic nature of alpha emission, hits and energy deposition poses some challenges for estimating radiation damage. In this paper we investigate the distribution of hits to cells by multiple alpha particles corresponding to a typical clinically delivered dose using a Monte Carlo model to simulate the stochastic effects. The number of hits and dose deposition were recorded in the cytoplasm and nucleus of each cell. Alpha particle tracks were also visualized. We found that the stochastic variation in dose deposited in cell nuclei (≃ 40%) can be attributed in part to the variation in LET with pathlength. We also found that ≃ 18% of cell nuclei receive less than one sigma below the average dose per cell (≃ 15.4 Gy). One possible implication of this is that the efficacy of cell kill in alpha particle therapy need not rely solely on ionization clustering on DNA but possibly also on indirect DNA damage through the production of free radicals and ensuing intracellular signaling.

  3. Effect of substrates on the molecular orientation of silicon phthalocyanine dichloride thin films

    NASA Astrophysics Data System (ADS)

    Deng, Juzhi; Baba, Yuji; Sekiguchi, Tetsuhiro; Hirao, Norie; Honda, Mitsunori

    2007-05-01

    Molecular orientations of silicon phthalocyanine dichloride (SiPcCl2) thin films deposited on three different substrates have been measured by near-edge x-ray absorption fine structure (NEXAFS) spectroscopy using linearly polarized synchrotron radiation. The substrates investigated were highly oriented pyrolitic graphite (HOPG), polycrystalline gold and indium tin oxide (ITO). For thin films of about five monolayers, the polarization dependences of the Si K-edge NEXAFS spectra showed that the molecular planes of SiPcCl2 on three substrates were nearly parallel to the surface. Quantitative analyses of the polarization dependences revealed that the tilted angle on HOPG was only 2°, which is interpreted by the perfect flatness of the HOPG surface. On the other hand, the tilted angle on ITO was 26°. Atomic force microscopy (AFM) observation of the ITO surface showed that the periodicity of the horizontal roughness is of the order of a few nanometres, which is larger than the molecular size of SiPcCl2. It is concluded that the morphology of the top surface layer of the substrate affects the molecular orientation of SiPcCl2 molecules not only for mono-layered adsorbates but also for multi-layered thin films.

  4. A systematic computational study of electronic effects on hydrogen sensitivity of olefin polymerization catalysts (abstract only).

    PubMed

    Coussens, Betty B; Budzelaar, Peter H M; Friederichs, Nic

    2008-02-13

    One of the important product parameters of polyolefins is their molecular weight (distribution). A common way to control this parameter is to add molecular hydrogen during the polymerization, which then acts as a chain transfer agent. The factors governing the hydrogen sensitivity of olefin polymerization catalysts are poorly understood and have attracted little attention from computational chemists. To explore the electronic factors determining hydrogen sensitivity we performed density functional calculations on a wide range of simple model systems including some metallocenes and a few basic models of heterogeneous catalysts. As a quantitative measure for hydrogen sensitivity we used the ratio of (i) the rate constant for chain transfer to hydrogen to (ii) the rate constant for ethene insertion, k(h)/k(p) (see the scheme below), and as a measure of electrophilicity we used the energy of complexation to the probe molecule ammonia. [Formula: see text] For isolated species in the gas phase, complexation energies appear to dominate the chemistry. Ethene complexes more strongly than hydrogen and with increasing electrophilicity of the metal centre this difference grows; the hydrogen sensitivity decreases accordingly. Although many factors (like catalyst dormancy and deactivation issues) complicate the comparison with experiment, this result seems to agree both in broad terms with the experimental lower hydrogen sensitivity of heterogeneous catalysts, and more specifically with the increased hydrogen sensitivity of highly alkylated or fused metallocenes. The opposite conclusion reached by Blom (see Blom et al 2002 Macromol. Chem. Phys. 203 381-7) is due to the use of a very different measure of electrophilicity, rather than to different experimental data.

  5. 21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) (1), (2), (3), (4), (5), (6), and (7) of this section. (1) Di(n-octyl)tin S,S′-bis(isooctylmercaptoacetate) is an octyltin chemical having 15.1 to 16.4 percent by weight of tin (Sn) and having 8.1 to 8.9 percent by weight of mercapto sulfur. It is made from di(n-octyl)tin dichloride or di(n-octyl)tin oxide...

  6. 21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) (1), (2), (3), (4), (5), (6), and (7) of this section. (1) Di(n-octyl)tin S,S′-bis(isooctylmercaptoacetate) is an octyltin chemical having 15.1 to 16.4 percent by weight of tin (Sn) and having 8.1 to 8.9 percent by weight of mercapto sulfur. It is made from di(n-octyl)tin dichloride or di(n-octyl)tin oxide...

  7. 21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) (1), (2), (3), (4), (5), (6), and (7) of this section. (1) Di(n-octyl)tin S,S′-bis(isooctylmercaptoacetate) is an octyltin chemical having 15.1 to 16.4 percent by weight of tin (Sn) and having 8.1 to 8.9 percent by weight of mercapto sulfur. It is made from di(n-octyl)tin dichloride or di(n-octyl)tin oxide...

  8. 21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) (1), (2), (3), (4), (5), (6), and (7) of this section. (1) Di(n-octyl)tin S,S′-bis(isooctylmercaptoacetate) is an octyltin chemical having 15.1 to 16.4 percent by weight of tin (Sn) and having 8.1 to 8.9 percent by weight of mercapto sulfur. It is made from di(n-octyl)tin dichloride or di(n-octyl)tin oxide...

  9. Vibrational dynamics (IR, Raman, NRVS) and DFT study of new antitumor tetranuclearstannoxanecluster, Sn(IV)$-$oxo$-$${di$$-$o$-$vanillin} dimethyl dichloride

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

    Arjmand, F.; Sharma, S.; Usman, M.

    2016-06-21

    The vibrational dynamics of a newly synthesized tetrastannoxane was characterized with a combination of experimental (Raman, IR and tin-based nuclear resonance vibrational spectroscopy) and computational (DFT/B3LYP) methods, with an emphasis on the vibrations of the tin sites. The cytotoxic activity revealed a significant regression selectively against the human pancreatic cell lines.

  10. Pathophysiology of chronic pancreatitis induced by dibutyltin dichloride joint ethanol in mice

    PubMed Central

    Zhang, Hong; Liu, Bin; Xu, Xiao-Fan; Jiang, Ting-Ting; Zhang, Xiao-Qin; Shi, Ying-Li; Chen, Yu; Liu, Fang; Gu, Jie; Zhu, Lin-Jia; Wu, Nan

    2016-01-01

    AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis. METHODS: The mice were randomly divided into 2 groups (n = 50), control group and model group. The mice in model group were given ethanol (10%) in drinking water after injection of dibutyltin dichloride (DBTC) (8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein (60% ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin (FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen type I (COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) mRNA in the pancreas was assessed by real time PCR. RESULTS: DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group (P < 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 mRNA in pancreas decreased, but TIMP-1 mRNA increased at model group. CONCLUSION: DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis. PMID:26973392

  11. Pathophysiology of chronic pancreatitis induced by dibutyltin dichloride joint ethanol in mice.

    PubMed

    Zhang, Hong; Liu, Bin; Xu, Xiao-Fan; Jiang, Ting-Ting; Zhang, Xiao-Qin; Shi, Ying-Li; Chen, Yu; Liu, Fang; Gu, Jie; Zhu, Lin-Jia; Wu, Nan

    2016-03-14

    To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis. The mice were randomly divided into 2 groups (n = 50), control group and model group. The mice in model group were given ethanol (10%) in drinking water after injection of dibutyltin dichloride (DBTC) (8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein (60% ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin (FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen type I (COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) mRNA in the pancreas was assessed by real time PCR. DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group (P < 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 mRNA in pancreas decreased, but TIMP-1 mRNA increased at model group. DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis.

  12. SU-F-T-57: Delivered Activity Accuracy of Radium 223 Dichloride Injections, When Being Administrated for Castration Resistant Prostate Cancer, Symptomatic Bone Metastases. The Impact of Residual Activity in the Spent Syringe and Dispensing Accuracy of Ra 223

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

    Jennings, G

    Purpose: To quantify the delivered activity accuracy of Radium 223 dichloride injections, when being administrated for castration – resistant prostate cancer, symptomatic bone metastases. The impact of residual activity in the spent syringe and dispensing accuracy of Ra 223. Methods: The administration is by slow intravenous injection over 1 minute followed by double flushing of the 10 mL syringe and IV with saline. Eighty (80) procedures was used to investigate variations in the activity from the amount prescribed (µCi) = 1.35 × Patient weight Kg. The Activity dispensed into a 10mL syringe using a NIST traceable Capintec CRC-25R Chamber andmore » a cross calibrated capintec CRC-15R to measure activity in the syringe immediately before and after administration Results: The patients weight range from 121Ib to 235lb and doses ranging 74.25 µCi to 144.2 µCi. The deviation of dispensed dose vs Prescribed dose average +2.1% with a range of −1.1% to +5.7%. The Dose measured before administration ranges 79.3 µCi to 154.9 µCi. Deviation from the dispensed dose was show to average +2.9% with a range of −0.8% to +7.3%. The average residual dose post injection was 2.5 µCi or 2.2% of the pre injection activity. Ranging from 0.9 µCi to 6.2 µCi, 0.7% to 5.4% respectively. Subtracting the residual activity from that measured activity before injection and comparing it to prescription dose was shown to have an average variation of +2.7% with a range of −0.8% to 7.4%. Conclusion: The case resulted in the 6.2 µCi maximum residual dose had two syringes. A small, 82.8 µCi activity, case resulted in the 7.4% maximum variation in measures less residual verses prescription dose. The average +2.1 % dispenses activity of Ra 223 over the prescription dosage was seen to counteract the average 2.2% residual dosage found to remain in the syringe.« less

  13. Multiple cis-regulatory elements are involved in the complex regulation of the sieve element-specific MtSEO-F1 promoter from Medicago truncatula.

    PubMed

    Bucsenez, M; Rüping, B; Behrens, S; Twyman, R M; Noll, G A; Prüfer, D

    2012-09-01

    The sieve element occlusion (SEO) gene family includes several members that are expressed specifically in immature sieve elements (SEs) in the developing phloem of dicotyledonous plants. To determine how this restricted expression profile is achieved, we analysed the SE-specific Medicago truncatula SEO-F1 promoter (PMtSEO-F1) by constructing deletion, substitution and hybrid constructs and testing them in transgenic tobacco plants using green fluorescent protein as a reporter. This revealed four promoter regions, each containing cis-regulatory elements that activate transcription in SEs. One of these segments also contained sufficient information to suppress PMtSEO-F1 transcription in the phloem companion cells (CCs). Subsequent in silico analysis revealed several candidate cis-regulatory elements that PMtSEO-F1 shares with other SEO promoters. These putative sieve element boxes (PSE boxes) are promising candidates for cis-regulatory elements controlling the SE-specific expression of PMtSEO-F1. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  14. Reaction kinetics and product distributions in photoelectrochemical cells. Technical progress report, March 15, 1992--March 14, 1993

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

    Koval, C.A.

    1992-12-01

    Hot electron reaction studies at p-InP/CH{sub 3}CN interface revealed essential/desirable features for redox systems used to investigate hot carriers in photoelectrocehmical cells. Reduction of dibromoethylbenzene (DBEB) in presence of metallocene couples is being studied using rotating rink disk electrodes of n-and p-InP disks and Pt rings. At highly doped p-InP electrodes, reduction of DBEB can be very efficient (>30%). A minielectrochemical cell was used to investigate electron transfer at nonilluminated n-WSe{sub 2}/dimethylferrocene{sup +/0} interfaces.

  15. Exploring the Reduction of Fuel Consumption for Ship-to-Shore Connectors of the Marine Expeditionary Brigade

    DTIC Science & Technology

    2013-12-01

    include the Command Element (CE), the Aviation Combat Element (ACE), the Ground Combat Element ( GCE ), and the Combat Service Support Element (CSSE) (from...35 Figure 9. The upper level functional architecture for EW12 shows the three primary functions of F1-Assemble the Seabase, F2...Function F2-Perform Assault is decomposed to obtain the lower level specific functions. From this decomposition, the sub-function of F2.2- Gain Entry

  16. Efficient Quenching of Oligomeric Fluorophores on a DNA Backbone

    PubMed Central

    Wilson, James N.; Teo, Yin Nah; Kool, Eric T.

    2008-01-01

    The quenching properties of a series of oligodeoxyribosides bearing fluorophore ‘bases’ is described. Sequences of adjacent, π-stacked pyrenes exhibit stronger electronic interactions visible in both absorbance and emission spectra than pyrenes that are insulated by intervening adenines. Quenching by N, N′-dimethyl-4,4′-bipyridinium dichloride is efficient for excimer-and exciplex-forming oligomers, with Stern-Volmer constants comparable to conjugated polymer “superquenching” schemes. PMID:18027944

  17. Thermophysical Properties of Matter - The TPRC Data Series. Volume 6. Specific Heat - Nonmetallic Liquids and Gases

    DTIC Science & Technology

    1970-01-01

    dlcarbide (Cr5C2) Heptachromium tricarbide (CrTCj) Chromium chlorides: CrCl2 CrClj Chromium dichloride (CrC^) Chromium trichloride (CrC...methane (see Propane) Dysprosia (see Dysprosium oxide) Dysprosium Dysprosium trichloride hexahydrate (DyClj-6HjO) Dysprosium oxide (DyjOj...Dysprosium sesquioxide (see Dysprosium oxide) Didysprosium trioxide (see Dysprosium oxide) Erbia (see Erbium oxide) Erbium Erbium trichloride

  18. Synthesis of Improved Polyester Resins.

    DTIC Science & Technology

    1979-07-05

    p-phenylene bis(magnesium bromide) dispersed in 70 ml of hexane was added over a period of one hour. Residual Grignard reagent was washed from the...was prepared from p-phenylenedi(phenylphosphonyl chloride) (PPPC). The PPPC monomer was made from the p-phenylene bis(magnesium bromide) Grignard ...phenylphosphonyl dichloride removal. On cooling, the product was a viscous glassy liquid. It weighed 12.5 grams (113 percent based on 8g of Grignard

  19. Organotin-Induced Hemolysis, Shape Transformation and Intramembranous Aggregates in Human Erythrocytes

    DTIC Science & Technology

    1987-01-01

    tributyltin , triethyltin, tripropyltin. 3. Abbreviations: DBT, dibutylin dichloride; MBT, butyltinchloride dihydroxide; SnCl2, stannous chloride; TBT , tri...compounds induce membrane lysis at low concentrations (Byington et al., 1974). Tri-n-butvltin ( TBT ) is a very effective hemolytic agent, causing membrane...based on numbers of butyl chains or numbers of carbon atoms in alkyl chains. TBT has been shown to produce 60-70 nm diameter, tin-containing

  20. The allylation reactions of aromatic aldehydes and ketones with tin dichloride in water.

    PubMed

    Bian, Yan-Jiang; Xue, Wei-Li; Yu, Xu-Guang

    2010-01-01

    The allylation reactions of aromatic aldehydes and ketones were carried out in 31-86% yield using SnCl(2)-H(2)O system under ultrasound irradiation at r.t. for 5h. The reactions in the same system gave homoallyl alcohols in 21-84% yield with stirring at r.t. for 24h. Compared with traditional stirring methods, ultrasonic irradiation is more convenient and efficient.

  1. A feasibility study for high-temperature titanium reduction from TiCl4 using a magnesiothermic process

    NASA Astrophysics Data System (ADS)

    Ivanov, S. L.; Zablotsky, D.

    2018-05-01

    The current industrial practice for titanium extraction is a complex procedure, which produces a porous reaction mass of sintered titanium particulates fused to a steel retort wall with magnesium and MgCl2 trapped in the interstices. The reactor temperature is limited to approx. 900 °C due to the formation of fusible TiFe eutectic, which corrodes the retort and degrades the quality of titanium sponge. Here we examine the theoretical foundations and technological possibilities to design a shielded retort of niobium-zirconium alloy NbZr(1%), which is resistant to corrosion by titanium at high temperature. We consider the reactor at a temperature of approx. 1150 °C. Supplying stoichiometric quantities of reagents enables the reaction in the gas phase, whereas the exothermic process sustains the combustion of the reaction zone. When the pathway to the condenser is open, vacuum separation and evacuation of vaporized magnesium dichloride and excess magnesium into the water-cooled condenser take place. As both the reaction and the evacuation occur within seconds, the yield of the extraction is improved. We anticipate new possibilities for designing a device combining the retort function to conduct the reduction in the gas phase with fast vacuum separation of the reaction products and distillation of magnesium dichloride.

  2. An aqueous all-organic redox-flow battery employing a (2,2,6,6-tetramethylpiperidin-1-yl)oxyl-containing polymer as catholyte and dimethyl viologen dichloride as anolyte

    NASA Astrophysics Data System (ADS)

    Hagemann, Tino; Winsberg, Jan; Grube, Mandy; Nischang, Ivo; Janoschka, Tobias; Martin, Norbert; Hager, Martin D.; Schubert, Ulrich S.

    2018-02-01

    Herein we present a new redox-flow battery (RFB) that employs a (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) containing copolymer (P1) as catholyte and the viologen derivative N,N‧-dimethyl-4,4‧-bipyridinium dichloride (MV) as anolyte in an aqueous sodium chloride solution. This is the first time that a combination of an organic polymer and a low-molar-mass organic redox-active material is presented. The electrochemical behavior of the utilized charge-storage materials were investigated by cyclic voltammetry (CV) and feature reversible redox-reactions at E½ = 0.7 V (TEMPO/TEMPO+) and E½ = -0.6 V vs. AgCl/Ag (MV++/MV+•), which lead to a promising cell voltage of 1.3 V in the subsequent battery application. Studies were performed to determine the most suitable anion-exchange membrane (AEM), the ideal conducting salt concentration and the optimal flow rate. The resulting battery reveals a stable charge/discharge performance over 100 consecutive cycles with coulombic efficiencies of up to 95%, a high energy efficiency of 85% and an overall energy density of the electrolyte system of 3.8 W h L-1.

  3. Dissociative adsorption of CCl 4 on the Fe 3O 4(1 1 1)-(2×2) selvedge of α-Fe 2O 3(0 0 0 1)

    NASA Astrophysics Data System (ADS)

    Adib, K.; Mullins, D. R.; Totir, G.; Camillone, N.; Fitts, J. P.; Rim, K. T.; Flynn, G. W.; Osgood, R. M.

    2003-02-01

    The surface reactions of CCl 4 with the Fe 3O 4(1 1 1)-(2×2) selvedge of naturally occurring α-Fe 2O 3(0 0 0 1) single-crystals have been investigated using synchrotron X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD). CCl 4 was found to dissociate on the Fe 3O 4 surface at 100 K producing chemisorbed Cl and adsorbed CCl 2. TPD shows that the large majority of the dissociatively adsorbed CCl 2 fragments extract lattice oxygen and desorb as phosgene at >275 K. However, the XPS spectra show no evidence for the formation of surface-bound phosgene, at 100 K, indicating that its formation involves two steps. The first step, dissociation, is spontaneous at 100 K, whereas the second, oxygen atom abstraction to form phosgene, requires thermal excitation. Cl chemisorption yielded two separate species, the mono- and dichloride terminations of surface iron sites. The identification of these two surface terminations is based on the coverage dependence and the surface temperature history of their Cl 2p 3/2 peak intensity. For example, heating to >450 K allows the monochloride to transform into iron dichloride, indicating Cl adatom mobility at these temperatures.

  4. Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element

    PubMed Central

    Shaffer, Christopher D.; Chen, Elizabeth J.; Quisenberry, Thomas J.; Ko, Kevin; Braverman, John M.; Giarla, Thomas C.; Mortimer, Nathan T.; Reed, Laura K.; Smith, Sheryl T.; Robic, Srebrenka; McCartha, Shannon R.; Perry, Danielle R.; Prescod, Lindsay M.; Sheppard, Zenyth A.; Saville, Ken J.; McClish, Allison; Morlock, Emily A.; Sochor, Victoria R.; Stanton, Brittney; Veysey-White, Isaac C.; Revie, Dennis; Jimenez, Luis A.; Palomino, Jennifer J.; Patao, Melissa D.; Patao, Shane M.; Himelblau, Edward T.; Campbell, Jaclyn D.; Hertz, Alexandra L.; McEvilly, Maddison F.; Wagner, Allison R.; Youngblom, James; Bedi, Baljit; Bettincourt, Jeffery; Duso, Erin; Her, Maiye; Hilton, William; House, Samantha; Karimi, Masud; Kumimoto, Kevin; Lee, Rebekah; Lopez, Darryl; Odisho, George; Prasad, Ricky; Robbins, Holly Lyn; Sandhu, Tanveer; Selfridge, Tracy; Tsukashima, Kara; Yosif, Hani; Kokan, Nighat P.; Britt, Latia; Zoellner, Alycia; Spana, Eric P.; Chlebina, Ben T.; Chong, Insun; Friedman, Harrison; Mammo, Danny A.; Ng, Chun L.; Nikam, Vinayak S.; Schwartz, Nicholas U.; Xu, Thomas Q.; Burg, Martin G.; Batten, Spencer M.; Corbeill, Lindsay M.; Enoch, Erica; Ensign, Jesse J.; Franks, Mary E.; Haiker, Breanna; Ingles, Judith A.; Kirkland, Lyndsay D.; Lorenz-Guertin, Joshua M.; Matthews, Jordan; Mittig, Cody M.; Monsma, Nicholaus; Olson, Katherine J.; Perez-Aragon, Guillermo; Ramic, Alen; Ramirez, Jordan R.; Scheiber, Christopher; Schneider, Patrick A.; Schultz, Devon E.; Simon, Matthew; Spencer, Eric; Wernette, Adam C.; Wykle, Maxine E.; Zavala-Arellano, Elizabeth; McDonald, Mitchell J.; Ostby, Kristine; Wendland, Peter; DiAngelo, Justin R.; Ceasrine, Alexis M.; Cox, Amanda H.; Docherty, James E.B.; Gingras, Robert M.; Grieb, Stephanie M.; Pavia, Michael J.; Personius, Casey L.; Polak, Grzegorz L.; Beach, Dale L.; Cerritos, Heaven L.; Horansky, Edward A.; Sharif, Karim A.; Moran, Ryan; Parrish, Susan; Bickford, Kirsten; Bland, Jennifer; Broussard, Juliana; Campbell, Kerry; Deibel, Katelynn E.; Forka, Richard; Lemke, Monika C.; Nelson, Marlee B.; O'Keeffe, Catherine; Ramey, S. Mariel; Schmidt, Luke; Villegas, Paola; Jones, Christopher J.; Christ, Stephanie L.; Mamari, Sami; Rinaldi, Adam S.; Stity, Ghazal; Hark, Amy T.; Scheuerman, Mark; Silver Key, S. Catherine; McRae, Briana D.; Haberman, Adam S.; Asinof, Sam; Carrington, Harriette; Drumm, Kelly; Embry, Terrance; McGuire, Richard; Miller-Foreman, Drew; Rosen, Stella; Safa, Nadia; Schultz, Darrin; Segal, Matt; Shevin, Yakov; Svoronos, Petros; Vuong, Tam; Skuse, Gary; Paetkau, Don W.; Bridgman, Rachael K.; Brown, Charlotte M.; Carroll, Alicia R.; Gifford, Francesca M.; Gillespie, Julie Beth; Herman, Susan E.; Holtcamp, Krystal L.; Host, Misha A.; Hussey, Gabrielle; Kramer, Danielle M.; Lawrence, Joan Q.; Martin, Madeline M.; Niemiec, Ellen N.; O'Reilly, Ashleigh P.; Pahl, Olivia A.; Quintana, Guadalupe; Rettie, Elizabeth A.S.; Richardson, Torie L.; Rodriguez, Arianne E.; Rodriguez, Mona O.; Schiraldi, Laura; Smith, Joanna J.; Sugrue, Kelsey F.; Suriano, Lindsey J.; Takach, Kaitlyn E.; Vasquez, Arielle M.; Velez, Ximena; Villafuerte, Elizabeth J.; Vives, Laura T.; Zellmer, Victoria R.; Hauke, Jeanette; Hauser, Charles R.; Barker, Karolyn; Cannon, Laurie; Parsamian, Perouza; Parsons, Samantha; Wichman, Zachariah; Bazinet, Christopher W.; Johnson, Diana E.; Bangura, Abubakarr; Black, Jordan A.; Chevee, Victoria; Einsteen, Sarah A.; Hilton, Sarah K.; Kollmer, Max; Nadendla, Rahul; Stamm, Joyce; Fafara-Thompson, Antoinette E.; Gygi, Amber M.; Ogawa, Emmy E.; Van Camp, Matt; Kocsisova, Zuzana; Leatherman, Judith L.; Modahl, Cassie M.; Rubin, Michael R.; Apiz-Saab, Susana S.; Arias-Mejias, Suzette M.; Carrion-Ortiz, Carlos F.; Claudio-Vazquez, Patricia N.; Espada-Green, Debbie M.; Feliciano-Camacho, Marium; Gonzalez-Bonilla, Karina M.; Taboas-Arroyo, Mariela; Vargas-Franco, Dorianmarie; Montañez-Gonzalez, Raquel; Perez-Otero, Joseph; Rivera-Burgos, Myrielis; Rivera-Rosario, Francisco J.; Eisler, Heather L.; Alexander, Jackie; Begley, Samatha K.; Gabbard, Deana; Allen, Robert J.; Aung, Wint Yan; Barshop, William D.; Boozalis, Amanda; Chu, Vanessa P.; Davis, Jeremy S.; Duggal, Ryan N.; Franklin, Robert; Gavinski, Katherine; Gebreyesus, Heran; Gong, Henry Z.; Greenstein, Rachel A.; Guo, Averill D.; Hanson, Casey; Homa, Kaitlin E.; Hsu, Simon C.; Huang, Yi; Huo, Lucy; Jacobs, Sarah; Jia, Sasha; Jung, Kyle L.; Wai-Chee Kong, Sarah; Kroll, Matthew R.; Lee, Brandon M.; Lee, Paul F.; Levine, Kevin M.; Li, Amy S.; Liu, Chengyu; Liu, Max Mian; Lousararian, Adam P.; Lowery, Peter B.; Mallya, Allyson P.; Marcus, Joseph E.; Ng, Patrick C.; Nguyen, Hien P.; Patel, Ruchik; Precht, Hashini; Rastogi, Suchita; Sarezky, Jonathan M.; Schefkind, Adam; Schultz, Michael B.; Shen, Delia; Skorupa, Tara; Spies, Nicholas C.; Stancu, Gabriel; Vivian Tsang, Hiu Man; Turski, Alice L.; Venkat, Rohit; Waldman, Leah E.; Wang, Kaidi; Wang, Tracy; Wei, Jeffrey W.; Wu, Dennis Y.; Xiong, David D.; Yu, Jack; Zhou, Karen; McNeil, Gerard P.; Fernandez, Robert W.; Menzies, Patrick Gomez; Gu, Tingting; Buhler, Jeremy; Mardis, Elaine R.; Elgin, Sarah C.R.

    2017-01-01

    The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains. PMID:28667019

  5. Immobilization of mesoporous silica particles on stainless steel plates

    NASA Astrophysics Data System (ADS)

    Pasqua, Luigi; Morra, Marco

    2017-03-01

    A preliminary study aimed to the nano-engineering of stainless steel surface is presented. Aminopropyl-functionalized mesoporous silica is covalently and electrostatically anchored on the surface of stainless steel plates. The anchoring is carried out through the use of a nanometric spacer, and two different spacers are proposed (both below 2 nm in size). The first sample is obtained by anchoring to the stainless steel amino functionalized, a glutaryl dichloride spacer. This specie forms an amide linkage with the amino group while the unreacted acyl groups undergo hydrolysis giving a free carboxylic group. The so-obtained functionalized stainless steel plate is used as substrate for anchoring derivatized mesoporous silica particles. The second sample is prepared using 2-bromo-methyl propionic acid as spacer (BMPA). Successively, the carboxylic group of propionic acid is condensed to the aminopropyl derivatization on the external surface of the mesoporous silica particle through covalent bond. In both cases, a continuous deposition (coating thickness is around 10 μm) is obtained, in fact, XPS data do not reveal the metal elements constituting the plate. The nano-engineering of metal surfaces can represent an intriguing opportunity for producing long-term drug release or biomimetic surface.

  6. UV induced surface modification on improving the cytocompatibility of metallocene polyethylene.

    PubMed

    Jaganathan, Saravana K; Prasath, Mani M

    2018-01-01

    Demand for medical implants is rising day by day as the world becomes the place for more diseased and older people. Accordingly, in this research, metallocene polyethylene (mPE), a commonly used polymer was treated with UV rays for improving its biocompatibility. Scanning electron microscopy (SEM) images confirmed the formation of crests and troughs, which depicts the improvement of surface roughness of mPE substrates caused by UV etching. Accordingly, the contact angle measurements revealed that the wettability of mPE-2.5 J/cm2 (68.09º) and mPE-5 J/cm2 (57.93º) samples were found to be increased compared to untreated mPE (86.84º) indicating better hydrophilicity. Further, the UV treated surface exhibited enhanced blood compatibility as determined in APTT (untreated mPE- 55.3 ± 2.5 s, mPE-2.5 J/cm2 - 76.7 ± 4.1 s and mPE-5 J/cm2 - 112.3 ± 2 s) and PT (untreated mPE - 24.7 ± 1.5 s, mPE- 2.5 J/cm2 - 34.3 ± 1.1 s and mPE-5 J/cm2 - 43 ± 2 s) assay. Moreover, the treated mPE-2.5 J/cm2 (4.88%) and mPE-5 J/cm2 (1.79%) showed decreased hemolytic percentage compared to untreated mPE (15.40%) indicating better safety to red blood cells. Interestingly, the changes in physicochemical properties of mPE are directly proportional to the dosage of the UV rays. UV modified mPE surfaces were found to be more compatible as identified through MTT assay, photomicrograph and SEM images of the seeded 3T3 cell population. Hence UV-modified surface of mPE may be successfully exploited for medical implants.

  7. Pou1f1, the key transcription factor related to somatic growth in tilapia (Orechromis niloticus), is regulated by two independent post-transcriptional regulation mechanisms.

    PubMed

    Wang, Dongfang; Qin, Jingkai; Jia, Jirong; Yan, Peipei; Li, Wensheng

    2017-01-29

    This study aims to determine the post-transcriptional regulation mechanism of the transcription factor pou1f1 (pou class 1 homeobox 1), which is the key gene for pituitary development, somatic growth in vertebrates, and transcription of several hormone genes in teleost fish. MicroRNA miR-223-3p was identified as a bona fide target of pou1f; overexpression of miR-223-3p in primary pituitary cells led to the down-regulation of pou1f1 and downstream genes, and inhibition of miR-223-3p led to the up-regulation of pou1f1 in Nile tilapia dispersed primary pituitary cells. An adenylate-uridylate-rich element (AU-Rich element) was found in the 3'UTR of pou1f1 mRNA, and deletion of the AU-Rich element led to slower mRNA decay and therefore more protein output. A potential mutual relationship between miR-223-3p and the AU-rich element was also investigated, and the results demonstrated that with or without the AU-Rich element, miR-223-3p induced the up-regulation of a reporter system under serum starvation conditions, indicating that miR-223-3p and the AU-Rich element function independent of each other. This study is the first to investigate the post-transcriptional mechanism of pou1f1, which revealed that miR-223-3p down-regulated pou1f1 and downstream gene expressions, and the AU-Rich element led to rapid decay of pou1f1 mRNA. MicroRNA miR-223-3p and the AU-Rich element co-regulated the post-transcriptional expression of pou1f1 independently in Nile tilapia, demonstrating that pou1f1 is under the control of a dual post-transcription regulation mechanism. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Representation of the Coulomb Matrix Elements by Means of Appell Hypergeometric Function F 2

    NASA Astrophysics Data System (ADS)

    Bentalha, Zine el abidine

    2018-06-01

    Exact analytical representation for the Coulomb matrix elements by means of Appell's double series F 2 is derived. The finite sum obtained for the Appell function F 2 allows us to evaluate explicitly the matrix elements of the two-body Coulomb interaction in the lowest Landau level. An application requiring the matrix elements of Coulomb potential in quantum Hall effect regime is presented.

  9. [Analysis and Evaluation of Inorganic Elements in Euryale Semen from Different Habitats by Microwave Digestion-ICP-OES].

    PubMed

    Wang, Hong; Wu, Qi-nan; Wu, Cheng-ying; Fan, Xiu-he; Jiang, Zheng; Gu, Wei; Yue, Wei

    2015-01-01

    To establish a simple, rapid and efficient method for determination of different inorganic elements in Euryale Semen from different habitats. Inductively coupled plasma-optical emission spectrometry(ICP-OES) was applied to determine inorganic elements in Euryale Semen, and the results were analyzed by principal component analysis. Euryale Semen from different habitats contained the kind of inorganic elements ranging from 22 to 26, including micronutrient elements like Iron, Zinc, Selenium, Copper, Molybdenum, Chrome and Cobalt, as well as macronutrient elements such as Potassium, Calcium, Sodium, Magnesium and Phosphorus. Five factors were extracted and used to comprehensively evaluate Euryale Semen from 20 different habitats covered almost China. The comprehensive function was F = 0. 38828F1 + 0. 25603F2 + 0. 07617F3 + 0. 06860F4 + 0. 04868F5, which resulted in the top three samples coming from Jiangsu Gaoyou, Hunan Xiangxi and Jiangsu Suzhou respectively. The study indicates that ICP-OES is a quick, accurate and sensitive method to determine the contents of inorganic elements in Euryale Semen,which provides scientific and reliable reference for its quality control and safety assessment.

  10. Method for scavenging mercury

    DOEpatents

    Chang, Shih-ger [El Cerrito, CA; Liu, Shou-heng [Kaohsiung, TW; Liu, Zhao-rong [Beijing, CN; Yan, Naiqiang [Berkeley, CA

    2009-01-20

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  11. Method for scavenging mercury

    DOEpatents

    Chang, Shih-Ger [El Cerrito, CA; Liu, Shou-Heng [Kaohsiung, TW; Liu, Zhao-Rong [Beijing, CN; Yan, Naiqiang [Berkeley, CA

    2011-08-30

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  12. Method for scavenging mercury

    DOEpatents

    Chang, Shih-ger; Liu, Shou-heng; Liu, Zhao-rong; Yan, Naiqiang

    2010-07-13

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  13. Prostate Cancer and Pesticide Exposure in Diverse Populations in California’s Central Valley

    DTIC Science & Technology

    2008-12-01

    2.38 23.21 153 Control 15 years prior to DX 0.62 1.58 10.78 143 Benzimidazole Benomyl DX Year 0.28 1.57 15.82 163 1974 - 1999 0.60 1.77...prostate cancer with exposure to Benzimidazole Benomyl in California’s Central Valley 2005 - 2006 Benzimidazole Benomyl Frequency...associated with exposure to methyl bromide, captan, simazine, organochlorine group, paraquat dichloride and benzimidazole benomyl, after adjusting for

  14. Cubic phase stabilization in nanoparticles of hafnia-zirconia oxides: Particle-size and annealing environment effects

    NASA Astrophysics Data System (ADS)

    Lu, Chih-Hsin; Raitano, Joan M.; Khalid, Syed; Zhang, Lihua; Chan, Siu-Wai

    2008-06-01

    Amorphous hafnia (HfO2-y), zirconia (ZrO2-y), and hafnia-zirconia (xHfO2-y-(1-x)(ZrO2-y)) nanoparticles were prepared by combining aqueous solutions of hexamethylenetetramine (HMT) with hafnium dichloride oxide (HfOCl2ṡ8H2O), zirconium dichloride oxide (ZrOCl2ṡ8H2O), or a mixture of these two salts at room temperature. For pure hafnia, transmission electron microscopy showed that the lower cation concentration (0.01M) resulted in the precipitation of smaller amorphous nanoparticles relative to higher concentrations (0.015M-0.04M). Consequently, the lower concentration preparation route coupled with a reducing environment (H2:N2=9:91) during annealing at temperatures between 650 and 850°C allowed for nanoparticles with a cubic structure to be prepared as determined by x-ray diffraction. The structurally cubic hafnia nanoparticles were 6nm or less in diameter and equiaxed. Using the same method (0.01M total metal cation concentration and reducing environment during annealing), nanoparticles of cubic structure were prepared across the entire hafnia-zirconia compositional spectrum, with a critical particle size for the cubic structure of about 6nm. Nanoparticles of tetragonal and monoclinic structure were prepared by increasing the annealing temperature and/or using a less reducing environment. The unique role of HMT in sample preparation is discussed as well.

  15. Toxicity of paraquat in nestling birds: effects on plasma and tissue biochemistry in American kestrels

    USGS Publications Warehouse

    Hoffman, Daivd J.; Franson, J. Christian; Pattee, Oliver H.; Bunck, Christine M.; Murray, Helen C.

    1987-01-01

    Beginning the day after hatching, American kestrel (Falco sparverius) nestlings were orally dosed daily for 10 days with 5 μL/g of distilled water (controls), 10 mg/kg, 25 mg/kg, or 60 mg/kg of paraquat dichloride (1,1′-dimethyl-4,4′-bipyridinium dichloride) in distilled water. Forty-four percent of the nestlings receiving 60 mg/kg died after 4 days. Plasma LDH activity and total protein concentration were elevated, and plasma alkaline phosphatase activity was lower in survivors of the 60 mg/kg group at 10 days. Lung total sulfhydryl (TSH) and protein-bound sulfhydryl (PBSH) concentrations were significantly higher in the 10 mg/kg, 25 mg/kg, or 60 mg/kg groups. Lung DNA, RNA, protein, and hydroxyproline (collagen) concentrations were not significantly affected by treatment. Liver NPSH was lower in the 60 mg/kg group while liver glycogen concentration was not affected by treatment. Kidney DNA, RNA, and RNA to protein concentration ratio were higher in the 25 mg/kg or 60 mg/kg groups. These findings in combination with recently reported effects on growth and histopathology suggest that altricial nestling kestrels are more sensitive to paraquat exposure than young or adult birds of precocial species. From a comparative viewpoint, lungs of nestling kestrels are less sensitive to paraquat than mammalian lungs.

  16. Organotin Exposure and Vertebrate Reproduction: A Review

    PubMed Central

    de Araújo, Julia Fernandez Puñal; Podratz, Priscila Lang; Merlo, Eduardo; Sarmento, Isabela Valim; da Costa, Charles Santos; Niño, Oscar Mauricio Santamaria; Faria, Rodrigo Alves; Freitas Lima, Leandro Ceotto; Graceli, Jones Bernardes

    2018-01-01

    Organotin (OTs) compounds are organometallic compounds that are widely used in industry, such as in the manufacture of plastics, pesticides, paints, and others. OTs are released into the environment by anthropogenic actions, leading to contact with aquatic and terrestrial organisms that occur in animal feeding. Although OTs are degraded environmentally, reports have shown the effects of this contamination over the years because it can affect organisms of different trophic levels. OTs act as endocrine-disrupting chemicals (EDCs), which can lead to several abnormalities in organisms. In male animals, OTs decrease the weights of the testis and epididymis and reduce the spermatid count, among other dysfunctions. In female animals, OTs alter the weights of the ovaries and uteri and induce damage to the ovaries. In addition, OTs prevent fetal implantation and reduce mammalian pregnancy rates. OTs cross the placental barrier and accumulate in the placental and fetal tissues. Exposure to OTs in utero leads to the accumulation of lipid droplets in the Sertoli cells and gonocytes of male offspring in addition to inducing early puberty in females. In both genders, this damage is associated with the imbalance of sex hormones and the modulation of the hypothalamic–pituitary–gonadal axis. Here, we report that OTs act as reproductive disruptors in vertebrate studies; among the compounds are tetrabutyltin, tributyltin chloride, tributyltin acetate, triphenyltin chloride, triphenyltin hydroxide, dibutyltin chloride, dibutyltin dichloride, diphenyltin dichloride, monobutyltin, and azocyclotin. PMID:29545775

  17. Logic elements for reactor period meter

    DOEpatents

    McDowell, William P.; Bobis, James P.

    1976-01-01

    Logic elements are provided for a reactor period meter trip circuit. For one element, first and second inputs are applied to first and second chopper comparators, respectively. The output of each comparator is O if the input applied to it is greater than or equal to a trip level associated with each input and each output is a square wave of frequency f if the input applied to it is less than the associated trip level. The outputs of the comparators are algebraically summed and applied to a bandpass filter tuned to f. For another element, the output of each comparator is applied to a bandpass filter which is tuned to f to give a sine wave of frequency f. The outputs of the filters are multiplied by an analog multiplier whose output is 0 if either input is 0 and a sine wave of frequency 2f if both inputs are a frequency f.

  18. I. Direct observation of zirconocene-catalyzed alkene polymerization via NMR and the role of an aluminum alkyl during polymerization. II. Design and evaluation of an online nanoscience course for teachers

    NASA Astrophysics Data System (ADS)

    Tomasik, Janice Hall

    The plastics industry has been revolutionalized by development of group 4 metallocene polymerization catalysts. These catalysts have higher activities and stereoselectivities than traditional heterogeneous Ziegler-Natta polymerization catalysts, and produce polymers with narrower molecular weight distributions and with better control of the polymer stereochemistry. The reaction kinetics of catalytic alkene polymerizations are complicated and difficult to resolve macroscopically. To overcome these difficulties, research has used NMR spectroscopy to directly observe catalytic reaction intermediates; many advances in our understanding of the complex mechanisms behind these polymerization reactions have resulted. In this work, the direct observation of alkene insertion into zirconocene-polymeryls via NMR spectroscopy is presented. Alkenes studied are 3-methylpentene, styrene, and 1,4-pentadiene. Kinetic measurements are reported for the polymerization of 3-methylpentene by rac-(EBI)Zr(Me)(MeB(C6F 5)3) (EBI = C2H4(1-indenyl)2) and rac-(EBI)Zr(polyhexenyl)(MeB(C6F5) 3). Also presented are NMR spectroscopic characterizations of rac-(EBI)Zr(styrenyl)(MeB(C6F5)3) and rac-(EBI)Zr(1,4-pentadienyl)(MeB(C6F 5)3). In addition, NMR spectroscopy is used to directly monitor the behavior of an aluminum alkyl during the polymerization of 1-hexene by rac -(EBI)2Zr(Me)(MeB(C6F5)3). The rates of polymerization are not inhibited by Al(iBu) 2(BHT), Al(Me)(BHT)2, or Al(iBu)3 (BHT = 2,6-di- tert-butyl-4-methylphenyl). Detailed measurement of polymerization rate and catalyst speciation demonstrate that BHT modified aluminum alkyls protect active sites from decomposition in the presence of protic impurities such as methanol. Also presented in this work is the design and evaluation of an online course for teachers about nanoscience. Nanotechnology is an important emerging field that is estimated to need about 2 million workers worldwide by 2015. Therefore the educational system is being encouraged to incorporate major nanoscience concepts into curricula. In order to facilitate the integration of nanoscience, an online professional development course for teachers has been developed and offered at the University of Wisconsin-Madison. Evaluation results from the first three versions of the course indicate the online learning environment was very close to ideal. Comparisons of pre-instruction to post-instruction quiz responses indicate significant learning gains by participants. Importantly, survey results show the online course helped teachers to successfully incorporate nanoscience into their curricula.

  19. The chemistry of the superheavy elements. II. The stability of high oxidation states in group 11 elements: Relativistic coupled cluster calculations for the di-, tetra- and hexafluoro metallates of Cu, Ag, Au, and element 111

    NASA Astrophysics Data System (ADS)

    Seth, Michael; Cooke, Fiona; Schwerdtfeger, Peter; Heully, Jean-Louis; Pelissier, Michel

    1998-09-01

    The stability of the high oxidation states +3 and +5 in Group 11 fluorides is studied by relativistic Møller-Plesset (MP) and coupled cluster methods. Higher metal oxidation states are stabilized by relativistic effects. As a result, the hexafluoro complex of the Group 11 element with nuclear charge 111 and oxidation state +5 is the most stable compared to the other congeners. The results also suggest that AgF6- is thermodynamically stable and, therefore, it might be feasable to synthesize this compound. For the copper fluorides we observe very large oscillations in the Møller-Plesset series up to the fourth order. Nonrelativistic calculations lead to the expected trend in the metal-fluorine bond distances for the MF2- compounds, CuF2-

  20. Evolutionary Significance of Wolbachia-to-Animal Horizontal Gene Transfer: Female Sex Determination and the f Element in the Isopod Armadillidium vulgare.

    PubMed

    Cordaux, Richard; Gilbert, Clément

    2017-07-21

    An increasing number of horizontal gene transfer (HGT) events from bacteria to animals have been reported in the past years, many of which involve Wolbachia bacterial endosymbionts and their invertebrate hosts. Most transferred Wolbachia genes are neutrally-evolving fossils embedded in host genomes. A remarkable case of Wolbachia HGT for which a clear evolutionary significance has been demonstrated is the " f element", a nuclear Wolbachia insert involved in female sex determination in the terrestrial isopod Armadillidium vulgare . The f element represents an instance of bacteria-to-animal HGT that has occurred so recently that it was possible to infer the donor (feminizing Wolbachia closely related to the w VulC Wolbachia strain of A. vulgare ) and the mechanism of integration (a nearly complete genome inserted by micro-homology-mediated recombination). In this review, we summarize our current knowledge of the f element and discuss arising perspectives regarding female sex determination, unstable inheritance, population dynamics and the molecular evolution of the f element. Overall, the f element unifies three major areas in evolutionary biology: symbiosis, HGT and sex determination. Its characterization highlights the tremendous impact sex ratio distorters can have on the evolution of sex determination mechanisms and sex chromosomes in animals and plants.

  1. Sequential extraction of chromium, molybdenum, and vanadium in basic oxygen furnace slags.

    PubMed

    Spanka, Marina; Mansfeldt, Tim; Bialucha, Ruth

    2018-06-02

    Basic oxygen furnace slags (BOS) are by-products of basic oxygen steel production. Whereas the solubility of some elements from these slags has been well investigated, information about the mineralogy and related leaching, i.e., availability of the environmentally relevant elements chromium (Cr), molybdenum (Mo), and vanadium (V), is still lacking. The aim of this study was to investigate these issues with a modified, four-fraction-based, sequential extraction procedure (F1-F4), combined with X-ray diffraction, of two BOS. Extractants with increasing strength were used (F1 demineralized water, F2 CH 3 COOH + HCl, F3 Na 2 EDTA + NH 2 OH·HCl, and F4 HF + HNO 3 + H 2 O 2 ), and after each fraction, X-ray diffraction was performed. The recovery of Cr was moderate (66.5%) for one BOS, but significantly better (100.2%) for the other one. High recoveries were achieved for the other elements (Mo, 100.8-107.9% and V, 112.6-87.0%), indicating that the sequential extraction procedure was reliable when adapted to BOS. The results showed that Cr and Mo primarily occurred in F4, representing rather immobile elements under natural conditions, which were strongly bound into/onto Fe minerals (srebrodolskite, magnetite, hematite, or wustite). In contrast, V was more mobile with proportional higher findings in F2 and F3, and the X-ray diffraction results reveal that V was not solely bound into Ca minerals (larnite, hatrurite, kirschsteinite, and calcite), but also bound to Fe minerals. The results indicated that the total amount of recovery was a poor indicator of the availability of elements and did not correspond to the leaching of elements from BOS.

  2. Characterization of Hadamard vector classes in terms of least deviations of their elements from vectors of finite degree

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

    Radzievski, G V

    2001-12-31

    Let A be a linear operator with domain D(A) in a complex Banach space X. An element g element of D{sub {infinity}}(A):=intersection{sub j=1}{sup {infinity}}D(A{sup j}) is called a vector of degree at most {xi} (>0) relative to A if ||A{sup j}g||{<=}c(g){xi}{sup j}, j=0,1,.... The set of vectors of degree at most {xi} is denoted by G{sub {xi}}(A) and the least deviation of an element f of X from the set G{sub {xi}}(A) is denoted by E{sub {xi}}(f,A). For a fixed sequence of positive numbers ({psi}{sub j}){sub j=1}{sup {infinity}} consider a function {gamma}({xi}):=min{sub j=1,2,...}({xi}{psi}{sub j}){sup 1/j}. Conditions for the sequence ({psi}{submore » j}){sub j=1}{sup {infinity}} and the operator A are found that ensure the equality lim sup{sub j{yields}}{sub {infinity}}((||A{sup j}f||)/({psi}{sub j})){sup 1/j} = lim sup{sub {xi}}{sub {yields}}{sub {infinity}}{xi}/({gamma}(E{sub {xi}}(f,A){sup -1})) for f element of D{sub {infinity}}(A). If the quantity on the left-hand side of this formula is finite, then f belongs to the Hadamard class determined by the operator A and the sequence {l_brace}{psi}{sub j}{r_brace}{sub j=1}{sup {infinity}}. One consequence of the above formula is an expression in terms of E{sub {xi}}(f,A) for the radius of holomorphy of the vector-valued function F(zA)f, where f element of D{sub {infinity}}(A), and F(z):={sigma}{sub j=1}{sup {infinity}}z{sup j}/{psi}{sub j} is an entire function.« less

  3. Cytogenetic mapping of the Muller F element genes in Drosophila willistoni group.

    PubMed

    Pita, Sebastián; Panzera, Yanina; Lúcia da Silva Valente, Vera; de Melo, Zilpa das Graças Silva; Garcia, Carolina; Garcia, Ana Cristina Lauer; Montes, Martín Alejandro; Rohde, Claudia

    2014-10-01

    Comparative genomics in Drosophila began in 1940, when Muller stated that the ancestral haploid karyotype of this genus is constituted by five acrocentric chromosomes and one dot chromosome, named A to F elements. In some species of the willistoni group such as Drosophila willistoni and D. insularis, the F element, instead of a dot chromosome, has been incorporated into the E element, forming chromosome III (E + F fusion). The aim of this study was to investigate the scope of the E + F fusion in the willistoni group, evaluating six other species. Fluorescent in situ hybridization was used to locate two genes of the F element previously studied-cubitus interruptus (ci) and eyeless (ey)-in species of the willistoni and bocainensis subgroups. Moreover, polytene chromosome photomaps corresponding to the F element (basal portion of chromosome III) were constructed for each species studied. In D. willistoni, D. paulistorum and D. equinoxialis, the ci gene was located in subSectction 78B and the ey gene in 78C. In D. tropicalis, ci was located in subSection 76B and ey in 76C. In species of the bocainensis subgroup, ci and ey were localized, respectively, at subsections 76B and 76C in D. nebulosa and D. capricorni, and 76A and 76C in D. fumipennis. Despite the differences in the subsection numbers, all species showed the same position for ci and ey. The results confirm the synteny of E + F fusion in willistoni and bocainensis subgroups, and allow estimating the occurrence of this event at 15 Mya, at least.

  4. Scattering Matrix for Typical Urban Anthropogenic Origin Cement Dust and Discrimination of Representative Atmospheric Particulates

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Zhang, Yongming; Zhang, Qixing; Wang, Jinjun

    2018-03-01

    The complete scattering matrix for cement dust was measured as a function of scattering angle from 5° to 160° at a wavelength of 532 nm, as a representative of mineral dust of anthropogenic origin in urban areas. Other related characteristics of cement dust, such as particle size distribution, chemical composition, refractive index, and micromorphology, were also analyzed. For this objective, a newly improved apparatus was built and calibrated using water droplets. Measurements of water droplets were in good agreement with Lorenz-Mie calculations. To facilitate the direct applicability of measurements for cement dust in radiative transfer calculation, the synthetic scattering matrix was computed and defined over the full scattering angle range from 0° to 180°. The scattering matrices for cement dust and typical natural mineral dusts were found to be similar in trends and angular behaviors. Angular distributions of all matrix elements were confined to rather limited domains. To promote the application of light-scattering matrix in atmospheric observation and remote sensing, discrimination methods for various atmospheric particulates (cement dust, soot, smolder smoke, and water droplets) based on the angular distributions of their scattering matrix elements are discussed. The ratio -F12/F11 proved to be the most effective discrimination method when a single matrix element is employed; aerosol identification can be achieved based on -F12/F11 values at 90° and 160°. Meanwhile, the combinations of -F12/F11 with F22/F11 (or (F11 - F22)/(F11 + F22)) or -F12/F11 with F44/F11 at 160° can be used when multiple matrix elements at the same scattering angle are selected.

  5. A series of energetic metal pentazolate hydrates.

    PubMed

    Xu, Yuangang; Wang, Qian; Shen, Cheng; Lin, Qiuhan; Wang, Pengcheng; Lu, Ming

    2017-09-07

    Singly or doubly bonded polynitrogen compounds can decompose to dinitrogen (N 2 ) with an extremely large energy release. This makes them attractive as potential explosives or propellants, but also challenging to produce in a stable form. Polynitrogen materials containing nitrogen as the only element exist in the form of high-pressure polymeric phases, but under ambient conditions even metastability is realized only in the presence of other elements that provide stabilization. An early example is the molecule phenylpentazole, with a five-membered all-nitrogen ring, which was first reported in the 1900s and characterized in the 1950s. Salts containing the azide anion (N 3 - ) or pentazenium cation (N 5 + ) are also known, with compounds containing the pentazole anion, cyclo-N 5 - , a more recent addition. Very recently, a bulk material containing this species was reported and then used to prepare the first example of a solid-state metal-N 5 complex. Here we report the synthesis and characterization of five metal pentazolate hydrate complexes [Na(H 2 O)(N 5 )]·2H 2 O, [M(H 2 O) 4 (N 5 ) 2 ]·4H 2 O (M = Mn, Fe and Co) and [Mg(H 2 O) 6 (N 5 ) 2 ]·4H 2 O that, with the exception of the Co complex, exhibit good thermal stability with onset decomposition temperatures greater than 100 °C. For this series we find that the N 5 - ion can coordinate to the metal cation through either ionic or covalent interactions, and is stabilized through hydrogen-bonding interactions with water. Given their energetic properties and stability, pentazole-metal complexes might potentially serve as a new class of high-energy density materials or enable the development of such materials containing only nitrogen. We also anticipate that the adaptability of the N 5 - ion in terms of its bonding interactions will enable the exploration of inorganic nitrogen analogues of metallocenes and other unusual polynitrogen complexes.

  6. A series of energetic metal pentazolate hydrates

    NASA Astrophysics Data System (ADS)

    Xu, Yuangang; Wang, Qian; Shen, Cheng; Lin, Qiuhan; Wang, Pengcheng; Lu, Ming

    2017-09-01

    Singly or doubly bonded polynitrogen compounds can decompose to dinitrogen (N2) with an extremely large energy release. This makes them attractive as potential explosives or propellants, but also challenging to produce in a stable form. Polynitrogen materials containing nitrogen as the only element exist in the form of high-pressure polymeric phases, but under ambient conditions even metastability is realized only in the presence of other elements that provide stabilization. An early example is the molecule phenylpentazole, with a five-membered all-nitrogen ring, which was first reported in the 1900s and characterized in the 1950s. Salts containing the azide anion (N3-) or pentazenium cation (N5+) are also known, with compounds containing the pentazole anion, cyclo-N5-, a more recent addition. Very recently, a bulk material containing this species was reported and then used to prepare the first example of a solid-state metal-N5 complex. Here we report the synthesis and characterization of five metal pentazolate hydrate complexes [Na(H2O)(N5)]·2H2O, [M(H2O)4(N5)2]·4H2O (M = Mn, Fe and Co) and [Mg(H2O)6(N5)2]·4H2O that, with the exception of the Co complex, exhibit good thermal stability with onset decomposition temperatures greater than 100 °C. For this series we find that the N5- ion can coordinate to the metal cation through either ionic or covalent interactions, and is stabilized through hydrogen-bonding interactions with water. Given their energetic properties and stability, pentazole-metal complexes might potentially serve as a new class of high-energy density materials or enable the development of such materials containing only nitrogen. We also anticipate that the adaptability of the N5- ion in terms of its bonding interactions will enable the exploration of inorganic nitrogen analogues of metallocenes and other unusual polynitrogen complexes.

  7. Fast and effective low-temperature freezing extraction technique to determine organotin compounds in edible vegetable oil.

    PubMed

    Liu, Yingxia; Ma, Yaqian; Wan, Yiqun; Guo, Lan; Wan, Xiaofen

    2016-06-01

    Most organotin compounds that have been widely used in food packaging materials and production process show serious toxicity effects to human health. In this study, a simple and low-cost method based on high-performance liquid chromatography with inductively coupled plasma mass spectrometry for the simultaneous determination of four organotins in edible vegetable oil samples was developed. Four organotins including dibutyltin dichloride, tributyltin chloride, diphenyltin dichloride, and triphenyltin chloride were simultaneously extracted with methanol using the low-temperature precipitation process. After being concentrated, the extracts were purified by matrix solid-phase dispersion using graphitized carbon black. The experimental parameters such as extraction solvent and clean-up material were optimized. To evaluate the accuracy of the new method, the recoveries were investigated. In addition, a liquid chromatography with tandem mass spectrometry method was also proposed for comparison. The procedures of extracting and purifying samples for the analysis were simple and easy to perform batch operations, also showed good efficiency with lower relative standard deviation. The limits of detection of the four organotins were 0.28-0.59 μg/L, and the limits of quantification of the four organotins were 0.93-1.8 μg/L, respectively. The proposed method was successfully applied to the simultaneous analysis of the four organotins in edible vegetable oil. Some analytes were detected at the level of 2.5-28.8 μg/kg. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The use of halloysite functionalized with isothiouronium salts as an organic/inorganic hybrid adsorbent for uranium(VI) ions removal.

    PubMed

    Gładysz-Płaska, A; Majdan, M; Tarasiuk, B; Sternik, D; Grabias, E

    2018-07-15

    Elimination of U(VI) from nuclear wastes and from the underground water near the uranium mines is the serious problem. Therefore search for new sorbents for U(VI) is still a big challenge for the scientists. This paper investigates of U(VI) ions sorption on halloysite modified with the isothiouronium salts: S-dodecaneisothiouronium bromide (ligand 1), S,S'-dodecane-1,12-diylbis(isothiouronium bromide) (ligand 2), S-hexadecaneisothiouronium chloride (ligand 3), S,S'-naphthalene-1,4-diylbis(methylisothiouronium) dichloride (ligand 4), and S,S'-2,5-dimethylbenzene-1,4-diylbis(methylisothiouronium) dichloride (ligand 5). It was established that halloysite modified by the ligands with four nitrogen atoms in their structure (ligand-5, 2 and 4) was characterized by higher sorption capacity compared with that modified by the ligands with two donor nitrogens (ligand-1 and 3). The maximum sorption capacity of halloysite-5 toward U(VI) was 157 mg U/g and this places the modified mineral among the most effective sorbents for U(VI) removal from wastes. As follows from ATR, XPS and thermal degradation spectra of the sorption products [R-S-C(NH)(NH 2 )] n = 1-2 (UO 2 2+ ) complexes are formed on the external surface of the halloysite whereas oligomeric hydroxy complexes (UO 2 ) 3 (OH) 5 + and (UO 2 ) 4 (OH) 7 + are present in the interior of halloysite structure and interact predominantly with aluminols. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Diversity of P-element piRNA production among M' and Q strains and its association with P-M hybrid dysgenesis in Drosophila melanogaster.

    PubMed

    Wakisaka, Keiko Tsuji; Ichiyanagi, Kenji; Ohno, Seiko; Itoh, Masanobu

    2017-01-01

    Transposition of P elements in the genome causes P-M hybrid dysgenesis in Drosophila melanogaster . For the P strain, the P-M phenotypes are associated with the ability to express a class of small RNAs, called piwi-interacting small RNAs (piRNAs), that suppress the P elements in female gonads. However, little is known about the extent to which piRNAs are involved in the P-M hybrid dysgenesis in M' and Q strains, which show different abilities to regulate the P elements from P strains. To elucidate the molecular basis of the suppression of paternally inherited P elements, we analyzed the mRNA and piRNA levels of P elements in the F1 progeny between males of a P strain and nine-line females of M' or Q strains (M' or Q progenies). M' progenies showed the hybrid dysgenesis phenotype, while Q progenies did not. Consistently, the levels of P -element mRNA in both the ovaries and F1 embryos were higher in M' progenies than in Q progenies, indicating that the M' progenies have a weaker ability to suppress P -element expression. The level of P -element mRNA was inversely correlated to the level of piRNAs in F1 embryos. Importantly, the M' progenies were characterized by a lower abundance of P -element piRNAs in both young ovaries and F1 embryonic bodies. The Q progenies showed various levels of piRNAs in both young ovaries and F1 embryonic bodies despite all of the Q progenies suppressing P -element transposition in their gonad. Our results are consistent with an idea that the level of P -element piRNAs is a determinant for dividing strain types between M' and Q and that the suppression mechanisms of transposable elements, including piRNAs, are varied between natural populations.

  10. Electronic Structure of Actinides under Pressure

    NASA Astrophysics Data System (ADS)

    Johansson, Borje

    2006-03-01

    The series of heavy radioactive elements known as the actinides all have similar elemental properties. However, when the volume per atom in the condensed phase is illustrated as a function of atomic number, perhaps the most dramatic anomaly in the periodic table becomes apparent. The atomic volume of americium is almost 50% larger than it is for the preceding element plutonium. For the element after americium, curium, the atomic volume is very close to that of americium. The same holds also for the next elements berkelium and californium. Accordingly from americium and onwards the actinides behave very similar to the corresponding rare-earth elements - a second lanthanide series of metallic elements can be identified. This view is strongly supported by the fact that all these elements adopt the dhcp structure, a structure typical for the lanthanides. The reason for this behavior is found in the behavior of the 5f electrons. For the earlier actinides, up to and including plutonium, the 5f electrons form metallic states and contribute most significantly to the bonding. In Np and Pu they even dominate the bonding, while all of a sudden they become localized in Am, very much like the 4f electrons in the lanthanide series, and contribute no longer to the cohesion. This withdrawal of 5f bonding gives rise to the large volume expansion between plutonium and americium. This difference between the light and heavy actinide suggests that it would be most worthwhile to strongly compress the transplutonium elements, thereby forcing the individual 5f electron wave functions into strong contact with each other (overlap). Recently high pressure experiments have been performed for americium and curium and dramatic crystal structure changes have been observed. These results and other high pressure data will be discussed in relation to the basic electronic structure of these elements.

  11. Development and blood compatibility assessment of electrospun polyvinyl alcohol blended with metallocene polyethylene and plectranthus amboinicus (PVA/mPE/PA) for bone tissue engineering.

    PubMed

    Qi, Jie; Zhang, Huang; Wang, Yingzhou; Mani, Mohan Prasath; Jaganathan, Saravana Kumar

    2018-01-01

    Currently, the design of extracellular matrix (ECM) with nanoscale properties in bone tissue engineering is challenging. For bone tissue engineering, the ECM must have certain properties such as being nontoxic, highly porous, and should not cause foreign body reactions. In this study, the hybrid scaffold based on polyvinyl alcohol (PVA) blended with metallocene polyethylene (mPE) and plectranthus amboinicus (PA) was fabricated for bone tissue engineering via electrospinning. The fabricated hybrid nanocomposites were characterized by scanning electron microscopy (SEM), Fourier transform and infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), contact angle measurement, and atomic force microscopy (AFM). Furthermore, activated partial thromboplastin time (APTT), prothrombin time (PT), and hemolytic assays were used to investigate the blood compatibility of the prepared hybrid nanocomposites. The prepared hybrid nanocomposites showed reduced fiber diameter (238±45 nm) and also increased porosity (87%) with decreased pore diameter (340±86 nm) compared with pure PVA. The interactions between PVA, mPE, and PA were identified by the formation of the additional peaks as revealed in FTIR. Furthermore, the prepared hybrid nanocomposites showed a decreased contact angle of 51°±1.32° indicating a hydrophilic nature and exhibited lower thermal stability compared to pristine PVA. Moreover, the mechanical results revealed that the electrospun scaffold showed an improved tensile strength of 3.55±0.29 MPa compared with the pristine PVA (1.8±0.52 MPa). The prepared hybrid nanocomposites showed delayed blood clotting as noted in APTT and PT assays indicating better blood compatibility. Moreover, the hemolysis assay revealed that the hybrid nanocomposites exhibited a low hemolytic index of 0.6% compared with pure PVA, which was 1.6% suggesting the safety of the developed nanocomposite to red blood cells (RBCs). The prepared nanocomposites exhibited better physico-chemical properties, sufficient porosity, mechanical strength, and blood compatibility, which favors it as a valuable candidate in bone tissue engineering for repairing the bone defects.

  12. Diffusion of Redox-Sensitive Elements in Basalt at Different Oxygen Fugacities

    NASA Technical Reports Server (NTRS)

    Szumila, I.; Trail, D.; Danielson, L. R.

    2017-01-01

    The terrestrial planets and moons of our solar system have differentiated over a range of oxygen fugacity conditions. Basalts formed from magmas on the Earth cover a range of more oxidized states (from approximately IW (iron wustite) plus 2 to approximately FMQ (fayalite-magnetite-quartz) plus 3) than crustal rocks from Mars (IW to approximately IW plus 3), and basalts from the Moon are more reduced than both, ranging from IW to IW minus 2. The small body Vesta differentiated around IW minus 4. Characterization of redox sensitive elements' diffusivities will offer insight into behavior of these elements as a function of f (fugacity of) O2 for these planetary bodies. Here, we report a systematic study of the diffusion of redox-sensitive elements in basaltic melts with varying oxygen fugacities (fO2) for trace elements, V, Nb, W, Mo, La, Ce, Pr, Sm, Eu, Gd, Ta, and W. Since fO2 is an intensive variable that is different for the reservoirs of various planets and moons in our solar system, it is important to characterize how changes in redox states will affect diffusion. We conducted experiments in a piston cylinder device at 1300 degrees Centigrade and 1 gigapascal, at the University of Rochester and NASA Johnson Space Center. We buffered some experiments at Ru-RuO2 (FMQ plus 6.00), and conducted other experiments within either a graphite or Mo capsule, which corresponds to fO2s of either FMQ minus1.2, or FMQ minus 3.00, respectively. Characterizing the diffusivities of redox sensitive elements at different fO2s is important because some elements, like Eu, have varying valence states, such as Eu (sup 2 plus) and Eu (sup 3 plus). Differences in charge and ion radii may lead to differences in diffusivities within silicate melts. This could, lead to formation of a Eu anomaly by diffusion, the magnitude of which may be controlled by the fO2. Characterization of trace element diffusion is also important in understanding trace element fractionation. We found, during the course of our investigation, that not only did the diffusivities of the redox sensitive elements change with fO2, but that the diffusivities of all other analyzed elements also changed. This indicates that not only do changes in valence influence trace elements diffusivities but that the structure of melt may have changed with varying oxygen fugacity, probably due to changes in the speciation of the major element Fe.

  13. Energy gap formation mechanism through the interference phenomena of electrons in face-centered cubic elements and compounds with the emphasis on half-Heusler and Heusler compounds

    NASA Astrophysics Data System (ADS)

    Mizutani, U.; Sato, H.

    2018-05-01

    Many face-centred cubic elements and compounds with the number of atoms per unit cell N equal to 8, 12 and 16 are known to be stabilised by forming either a band gap or a pseudogap at the Fermi level. They are conveniently expressed as cF8, cF12 and cF16, respectively, in the Pearson symbol. From the cF8 family, we worked on three tetravalent elements C (diamond), Si and Ge, SZn-type AsGa compound and NaCl-type compounds like BiLu, AsSc, etc. From the cF12 family, more than 80 compounds were selected, with a particular emphasis on ABC- and half-Heusler-type ternary equiatomic compounds. Among cF16 compounds, both the Heusler compounds ABC2 and Zintl compounds were studied. We revealed that, regardless of whether or not the transition metal (TM) and/or rare-earth (RE) elements are involved as constituent elements, the energy gap formation mechanism for cF8, cF12 and cF16 compounds can be universally discussed in terms of interference phenomenon of itinerant electrons with set of reciprocal lattice planes with ? = 8, 11 and 12, where ? refers to square of the critical reciprocal of lattice vector of an fcc lattice. The number of itinerant electrons per unit cell, e/uc, for all these band gap/pseudogap-bearing compounds is found to fall on a universal line called "3/2-power law" when plotted against ? on a logarithmic scale. This proves the validity of the fulfilment of the interference condition ? in conformity with other pseudogap compounds with different crystal symmetries and different sizes of the unit cell reported in literature.

  14. Air Emissions Inventory Guidance Document for Mobile Sources at Air Force Installations

    DTIC Science & Technology

    2002-01-01

    Compounds 156-62-7 Calcium cyanamide 133-06-2 Captan 63-25-2 Carbaryl 75-15-0 Carbon disulfide 56-23-5 Carbon tetrachloride 463-58-1 Carbonyl sulfide...1120-71-4 1,3-Propane sultone 57-57-8 beta-Propiolactone, 123-38-6 Propionaldehyde 114-26-1 Propoxur (Baygon) 78-87-5 Propylene dichloride, (1 ,2...Dichlorvos 62-75-9 N-Nitrosodimethylamine 63-25-2 Carbaryl 64-67-5 Diethyl sulfate 67-56-1 Methanol 67-66-3 Chloroform 67-72-1 Hexachloroethane 68-12-2

  15. One-Pot Conversion of Epoxidized Soybean Oil (ESO) into Soy-Based Polyurethanes by MoCl₂O₂ Catalysis.

    PubMed

    Pantone, Vincenzo; Annese, Cosimo; Fusco, Caterina; Fini, Paola; Nacci, Angelo; Russo, Antonella; D'Accolti, Lucia

    2017-02-21

    An innovative and eco-friendly one-pot synthesis of bio-based polyurethanes is proposed via the epoxy-ring opening of epoxidized soybean oil (ESO) with methanol, followed by the reaction of methoxy bio-polyols intermediates with 2,6-tolyl-diisocyanate (TDI). Both synthetic steps, methanolysis and polyurethane linkage formation, are promoted by a unique catalyst, molybdenum(VI) dichloride dioxide (MoCl₂O₂), which makes this procedure an efficient, cost-effective, and environmentally safer method amenable to industrial scale-up.

  16. Crosslinking of aromatic polyamides via pendant propargyl groups

    NASA Technical Reports Server (NTRS)

    St.clair, A. K.; St.clair, T. L.; Barrick, J. D.; Campbell, F. J.

    1980-01-01

    Methods for crosslinking N-methyl substituted aromatic polyamides were investigated in an effort to improve the applicability of these polymers as matrix resins for Kavlar trademark fiber composites. High molecular weight polymers were prepared from isophthaloyl dichloride and 4,4'- bis(methylamino)diphenylmethane with varying proportions of the N,N'bispropargyl diamine incorporated as a crosslinking agent. The propargylcontaining diamines were crosslinked thermally and characterized by infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Attempts were also made to crosslink polyamide films by exposure to ultraviolet light, electron beam, and gamma radiation.

  17. Removal of ash, sulfur, and trace elements of environmental concern from eight selected Illinois coals

    USGS Publications Warehouse

    Demir, I.

    1998-01-01

    Release analysis (RA) and float-sink (F-S) data were generated to assess the beneficiation potential of washed coals from selected Illinois coal preparation plants through the use of advanced physical cleaning at -60 mesh size. Generally, the F-S process removed greater amounts of ash, sulfur, and trace elements of environmental concern from the coals than the RA process, indicating that the cleanability of Illinois coals by advanced methods can be estimated best by F-S testing. At an 80%-combustibles recovery, the ash yield in the clean F-S products decreased by 47-75%, relative to the parent coals. Average decreases for the elements As(67%), Cd(78%), Hg(73%), Mn(71%), and P(66%) exceeded the average decrease for ash yield (55%). Average decreases for other elements were: Co(31%), Cr(27%), F(39%), Ni(25%), Pb(50%), S(28%), Sb(20%), Se(39), Th(32%), and U(8%). Only Be was enriched (up to 120%) in the clean products relative to the parent coals. These results suggested that the concentration of elements with relatively high atmospheric mobilities (As, Cd, F, Hg, Pb, and Se) during coal combustion can be reduced substantially in Illinois coals through the use of advanced physical cleaning. Advanced physical cleaning can be effective also for the removal of inorganic S. Environmental risks from the emission of other elements with enrichment or relatively low cleanabilities could be small because these elements generally have very low concentrations in Illinois coals or are largely retained in solid residues during coal combustion. ?? 1998 OPA (Overseas Publishers Association) N.V. Published by license under the Gordon and Breach Science Publishers imprint.

  18. Metallocene-based antimalarials: an exploration into the influence of the ferrocenyl moiety on in vitro antimalarial activity in chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum.

    PubMed

    Blackie, Margaret A L; Beagley, Paul; Croft, Simon L; Kendrick, Howard; Moss, John R; Chibale, Kelly

    2007-10-15

    To establish the role of the ferrocenyl moiety in the antiplasmodial activity of ferroquine, compounds in which this moiety is replaced by the corresponding ruthenium-based moieties were synthesized and evaluated. In both the sensitive (D10) and resistant (K1) strains of Plasmodium falciparum, ruthenoquine analogues showed comparable potency to ferroquine. This suggests that a probable role of the ferrocenyl fragment is to serve simply as a hydrophobic spacer group. In addition, ferroquine analogues with different aromatic substituents were synthesized and evaluated. Unexpectedly high activity for quinoline compounds lacking the 7-chloro substituent suggests the ferrocenyl moiety may have an additive and/or synergistic effect.

  19. Photoproduction of Hydrogen by Decamethylruthenocene Combined with Electrochemical Recycling.

    PubMed

    Rivier, Lucie; Peljo, Pekka; Vannay, Laurent A C; Gschwend, Grégoire C; Méndez, Manuel A; Corminboeuf, Clémence; Scanlon, Micheál D; Girault, Hubert H

    2017-02-20

    The photoinduced hydrogen evolution reaction (HER) by decamethylruthenocene, Cp 2 *Ru II (Cp*=C 5 Me 5 ), is reported. The use of a metallocene to photoproduce hydrogen is presented as an alternative strategy to reduce protons without involving an additional photosensitizer. The mechanism was investigated by (spectro)electrochemical and spectroscopic (UV/Vis and 1 H NMR) measurements. The photoactivated hydride involved was characterized spectroscopically and the resulting [Cp 2 *Ru III ] + species was electrochemically regenerated in situ on a fluorinated tin oxide electrode surface. A promising internal quantum yield of 25 % was obtained. Optimal experimental conditions- especially the use of weakly coordinating solvent and counterions-are discussed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Catalyst system for the polymerization of alkenes to polyolefins

    DOEpatents

    Miller, Stephen A.; Bercaw, John E.

    2002-01-01

    The invention provides metallocene catalyst systems for the controlled polymerization of alkenes to a wide variety of polyolefins and olefin coplymers. Catalyst systems are provided that specifically produce isotactic, syndiotactic and steroblock polyolefins. The type of polymer produced can be controlled by varying the catalyst system, specifically by varying the ligand substituents. Such catalyst systems are particularly useful for the polymerization of polypropylene to give elastomeric polypropylenes. The invention also provides novel elastomeric polypropylene polymers characterized by dyad (m) tacticities of about 55% to about 65%, pentad (mmmm) tacticities of about 25% to about 35%, molecular weights (M.sub.w)in the range of about 50,000 to about 2,000,000, and have mmrm+rrmr peak is less than about 5%.

  1. Catalyst system for the polymerization of alkenes to polyolefins

    DOEpatents

    Miller, Stephen A.; Bercaw, John E.

    2004-02-17

    The invention provides metallocene catalyst systems for the controlled polymerization of alkenes to a wide variety of polyolefins and olefin coplymers. Catalyst systems are provided that specifically produce isotactic, syndiotactic and steroblock polyolefins. The type of polymer produced can be controlled by varying the catalyst system, specifically by varying the ligand substituents. Such catalyst systems are particularly useful for the polymerization of polypropylene to give elastomeric polypropylenes. The invention also provides novel elastomeric polypropylene polymers characterized by dyad (m) tacticities of about 55% to about 65%, pentad (mmmm) tacticities of about 25% to about 35%, molecular weights (M.sub.W) in the range of about 50,000 to about 2,000,000, and have mmrm+rrmr peak is less than about 5%.

  2. Trace element emissions from spontaneous combustion of gob piles in coal mines, Shanxi, China

    USGS Publications Warehouse

    Zhao, Y.; Zhang, Jiahua; Chou, C.-L.; Li, Y.; Wang, Z.; Ge, Y.; Zheng, C.

    2008-01-01

    The emissions of potentially hazardous trace elements from spontaneous combustion of gob piles from coal mining in Shanxi Province, China, have been studied. More than ninety samples of solid waste from gob piles in Shanxi were collected and the contents of twenty potentially hazardous trace elements (Be, F, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sn, Sb, Hg, Tl, Pb, Th, and U) in these samples were determined. Trace element contents in solid waste samples showed wide ranges. As compared with the upper continental crust, the solid waste samples are significantly enriched in Se (20x) and Tl (12x) and are moderately enriched in F, As, Mo, Sn, Sb, Hg, Th, and U (2-5x). The solid waste samples are depleted in V, Cr, Mn, Co, Ni, Cu, and Zn. The solid waste samples are enriched in F, V, Mn, Cr, Co, Ni, Cu, Zn, Sb, Th, and U as compared with the Shanxi coals. Most trace elements are higher in the clinker than in the unburnt solid waste except F, Sn, and Hg. Trace element abundances are related to the ash content and composition of the samples. The content of F is negatively correlated with the ash content, while Pb is positively correlated with the ash. The concentrations of As, Mn, Zn, and Cd are highly positively correlated with Fe2O3 in the solid waste. The As content increases with increasing sulfur content in the solid waste. The trace element emissions are calculated for mass balance. The emission factors of trace elements during the spontaneous combustion of the gobs are determined and the trace element concentrations in the flue gas from the spontaneous combustion of solid waste are calculated. More than a half of F, Se, Hg and Pb are released to the atmosphere during spontaneous combustion. Some trace element concentrations in flue gas are higher than the national emission standards. Thus, gob piles from coal mining pose a serious environmental problem. ?? 2007 Elsevier B.V. All rights reserved.

  3. Stable-carbon isotope ratios for sourcing the nerve-agent precursor methylphosphonic dichloride and its products

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

    Moran, James J.; Fraga, Carlos G.; Nims, Megan K.

    The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. It is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ13C analysis to be used as a fingerprinting toolmore » in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. We demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a measureable isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool.« less

  4. Stable-Carbon Isotope Ratios for Sourcing the Nerve-Agent Precursor Methylphosphonic Dichloride and Its Products

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

    Moran, James J.; Fraga, Carlos G.; Nims, Megan K.

    The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. DC is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ 13C analysis to be used as a fingerprintingmore » tool in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. Here, we demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a significant isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool.« less

  5. Stable-Carbon Isotope Ratios for Sourcing the Nerve-Agent Precursor Methylphosphonic Dichloride and Its Products

    DOE PAGES

    Moran, James J.; Fraga, Carlos G.; Nims, Megan K.

    2018-04-01

    The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. DC is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ 13C analysis to be used as a fingerprintingmore » tool in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. Here, we demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a significant isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool.« less

  6. Stable-carbon isotope ratios for sourcing the nerve-agent precursor methylphosphonic dichloride and its products.

    PubMed

    Moran, James J; Fraga, Carlos G; Nims, Megan K

    2018-08-15

    The ability to connect a chemical threat agent to a specific batch of a synthetic precursor can provide a fingerprint to contribute to effective forensic investigations. Stable isotope analysis can leverage intrinsic, natural isotopic variability within the molecules of a threat agent to unlock embedded chemical fingerprints in the material. Methylphosphonic dichloride (DC) is a chemical precursor to the nerve agent sarin. DC is converted to methylphosphonic difluoride (DF) as part of the sarin synthesis process. We used a suite of commercially available DC stocks to both evaluate the potential for δ 13 C analysis to be used as a fingerprinting tool in sarin-related investigations and to develop sample preparation techniques (using chemical hydrolysis) that can simplify isotopic analysis of DC and its synthetic products. We demonstrate that natural isotopic variability in DC results in at least three distinct, isotope-resolved clusters within the thirteen stocks we analyzed. Isotopic variability in the carbon feedstock (i.e., methanol) used for DC synthesis is likely inherited by the DC samples we measured. We demonstrate that the hydrolysis of DC and DF to methylphosphonic acid (MPA) can be used as a preparative step for isotopic analysis because the reaction does not impart a significant isotopic fractionation. MPA is more chemically stable, less toxic, and easier to handle than DC or DF. Further, the hydrolysis method we demonstrated can be applied to a suite of other precursors or to sarin itself, thereby providing a potentially valuable forensic tool. Copyright © 2018. Published by Elsevier B.V.

  7. Zircon/fluid trace element partition coefficients measured by recrystallization of Mud Tank zircon at 1.5 GPa and 800-1000 °C

    NASA Astrophysics Data System (ADS)

    Ayers, John C.; Peters, Timothy J.

    2018-02-01

    Hydrothermal zircon grains have trace element characteristics such as low Th/U, high U, and high rare earth element (REE) concentrations that distinguish them from magmatic, metamorphic, and altered zircon grains, but it is unclear whether these characteristics result from distinctive fluid compositions or zircon/fluid fractionation effects. New experiments aimed at measuring zircon/fluid trace element partition coefficients Dz/f involved recrystallizing natural Mud Tank zircon with low trace element concentrations in the presence of H2O, 1 m NaOH, or 1 m HCl doped with ∼1000 ppm of rare earth elements (REE), Y, U and Th and ∼500 ppm of Li, B, P, Nb, Ba, Hf, and Ta. Experiments were run for 168 h at 1.5 GPa, 800-1000 °C, and fO2 = NNO in a piston cylinder apparatus using the double capsule method. LA-ICP-MS analysis shows that run product zircon crystals have much higher trace element concentrations than in Mud Tank zircon starting material. Dz/f values were estimated from run product zircon analyses and bulk composition using mass balance. Most elements behave incompatibly, with median Dz/f being highest for Hf = 8 and lowest for B = 0.02. Addition of NaOH or HCl had little influence on Dz/f values. Dz/f for LREE are anomalously high, likely due to contamination of run product zircon with quenched solutes enriched in incompatible elements, so DLREE were estimated using lattice strain theory. Brice curves for +3 ions yield zircon/fluid DLu/DLa of ∼800-5000. A Brice curve fit to +4 ions yielded DCe4+ values. Estimated concentrations of Ce3+ and Ce4+ show that the average Ce4+/Ce3+ in zircon of 27 is much higher than in fluid of 0.02. Th and U show little fractionation, with median DTh/DU = 0.7, indicating that the low Th/U in natural hydrothermal zircon is inherited from the fluid. Natural fluid compositions estimated from measured Dz/f and published compositions of hydrothermal zircon grains from aplite and eclogite reflect the mineralogy of the host rock, e.g., fluid in equilibrium with eclogite garnet is depleted in heavy REE relative to middle REE, and has low Th/U.

  8. Lunar mining of oxygen using fluorine

    NASA Technical Reports Server (NTRS)

    Burt, Donald M.; Tyburczy, James A.; Roberts, Jeffery J.; Balasubramanian, Rajan

    1992-01-01

    Experiments during the first year of the project were directed towards generating elemental fluorine via the electrolysis of anhydrous molten fluorides. Na2SiF6 was dissolved in either molten NaBF4 or a eutectic (minimum-melting) mixture of KF-LiF-NaF and electrolyzed between 450 and 600 C to Si metal at the cathode and F2 gas at the anode. Ar gas was continuously passed through the system and F2 was trapped in a KBr furnace. Various anode and cathode materials were investigated. Despite many experimental difficulties, the capability of the process to produce elemental fluorine was demonstrated.

  9. Sensitivity Analysis for Multidisciplinary Systems (SAMS)

    DTIC Science & Technology

    2016-12-01

    support both mode-based structural representations and time-dependent, nonlinear finite element structural dynamics. This interim report describes...Adaptation, & Sensitivity Toolkit • Elasticity, heat transfer, & compressible flow • Adjoint solver for sensitivity analysis • High-order finite elements ...PROGRAM ELEMENT NUMBER 62201F 6. AUTHOR(S) Richard D. Snyder 5d. PROJECT NUMBER 2401 5e. TASK NUMBER N/A 5f. WORK UNIT NUMBER Q1FS 7

  10. [Analysis of stress in periodontal ligament of the maxillary first molar on distal movement by nonlinear finite element method].

    PubMed

    Dong, Jing; Zhang, Zhe-chen; Zhou, Guo-liang

    2015-06-01

    To analyze the stress distribution in periodontal ligament of maxillary first molar during distal movement with nonlinear finite element analysis, and to compare it with the result of linear finite element analysis, consequently to provide biomechanical evidence for clinical application. The 3-D finite element model including a maxillary first molar, periodontal ligament, alveolar bone, cancellous bone, cortical bone and a buccal tube was built up by using Mimics, Geomagic, ProE and Ansys Workbench. The material of periodontal ligament was set as nonlinear material and linear elastic material, respectively. Loads of different combinations were applied to simulate the clinical situation of distalizing the maxillary first molar. There were channels of low stress in peak distribution of Von Mises equivalent stress and compressive stress of periodontal ligament in nonlinear finite element model. The peak of Von Mises equivalent stress was lower when it was satisfied that Mt/F minus Mr/F approximately equals 2. The peak of compressive stress was lower when it was satisfied that Mt/F was approximately equal to Mr/F. The relative stress of periodontal ligament was higher and violent in linear finite element model and there were no channels of low stress in peak distribution. There are channels in which stress of periodontal ligament is lower. The condition of low stress should be satisfied by applied M/F during the course of distalizing the maxillary first molar.

  11. Fractionation of trace elements and human health risk of submicron particulate matter (PM1) collected in the surroundings of coking plants.

    PubMed

    Zajusz-Zubek, Elwira; Radko, Tomasz; Mainka, Anna

    2017-08-01

    Samples of PM1 were collected in the surroundings of coking plants located in southern Poland. Chemical fractionation provided information on the contents of trace elements As, Cd, Co, Cr, Hg, Mn, Ni, Pb, Sb and Se in all mobile (F1-F3) and not mobile (F4) fractions of PM1 in the vicinity of large sources of emissions related to energochemical processing of coal during the summer. The determined enrichment factors indicate the influence of anthropogenic sources on the concentration of the examined elements contained in PM1 in the areas subjected to investigation. The analysis of health risk for the assumed scenario of inhabitant exposure to the toxic effect of elements, based on the values of the hazard index, revealed that the absorption of the examined elements contained in the most mobile fractions of particulate matter via inhalation by children and adults can be considered potentially harmless to the health of people inhabiting the surroundings of coking plants during the summer (HI < 1). It has been estimated that due to the inhalation exposure to carcinogenic elements, i.e., As, Cd, Co, Cr, Ni and Pb, contained in the most mobile fractions (F1 + F2) of PM1, approximately four adults and one child out of one million people living in the vicinity of the coking plants may develop cancer.

  12. Confinement in F4 Exceptional Gauge Group Using Domain Structures

    NASA Astrophysics Data System (ADS)

    Rafibakhsh, Shahnoosh; Shahlaei, Amir

    2017-03-01

    We calculate the potential between static quarks in the fundamental representation of the F4 exceptional gauge group using domain structures of the thick center vortex model. As non-trivial center elements are absent, the asymptotic string tension is lost while an intermediate linear potential is observed. SU(2) is a subgroup of F4. Investigating the decomposition of the 26 dimensional representation of F4 to the SU(2) representations, might explain what accounts for the intermediate linear potential, in the exceptional groups with no center element.

  13. A Radium-223 Microgenerator from Cyclotron-Produced Trace Actinium-227

    PubMed Central

    Abou, Diane S.; Pickett, Juile; Mattson, John E.; Thorek, Daniel L. J.

    2016-01-01

    The alpha particle emitter Radium-223 dichloride (223RaCl2) has recently been approved for treatment of late-stage bone metastatic prostate cancer. There is considerable interest in studying this new agent outside of the clinical setting, however the supply of 223Ra is limited and expensive. We have engineered a 223Ra microgenerator using traces of 227Ac previously generated from cyclotron-produced 225Ac. Radiochemically pure 223RaCl2 was made, characterized, evaluated in vivo, and the source was recovered in high yield for regeneration of the microgenerator. PMID:27835737

  14. Experimental elaboration and analysis of dye-sensitized TiO2 solar cells (DSSC) dyed by natural dyes and conductive polymers

    NASA Astrophysics Data System (ADS)

    KałuŻyński, P.; Maciak, E.; Herzog, T.; Wójcik, M.

    2016-09-01

    In this paper we propose low cost and easy in development fully working dye-sensitized solar cell module made with use of a different sensitizing dyes (various anthocyanins and P3HT) for increasing the absorption spectrum, transparent conducting substrates (vaccum spattered chromium and gold), nanometer sized TiO2 film, iodide and methyl viologen dichloride based electrolyte, and a counter electrode (vaccum spattered platinum or carbon). Moreover, some of the different technologies and optimization manufacturing processes were elaborated for energy efficiency increase and were presented in this paper.

  15. Reducing the duality gap in partially convex programming

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

    Correa, R.

    1994-12-31

    We consider the non-linear minimization program {alpha} = min{sub z{element_of}D, x{element_of}C}{l_brace}f{sub 0}(z, x) : f{sub i}(z, x) {<=} 0, i {element_of} {l_brace}1, ..., m{r_brace}{r_brace} where f{sub i}(z, {center_dot}) are convex functions, C is convex and D is compact. Following Ben-Tal, Eiger and Gershowitz we prove the existence of a partial dual program whose optimum is arbitrarily close to {alpha}. The idea, corresponds to the branching principle in Branch and Bound methods. We describe such a kind of algorithm for obtaining the desired partial dual.

  16. Ca(BH 4) 2 as a simple tool for the preparation of thorium and uranium metallocene borohydride complexes: First synthesis and crystal structure of (C 5Me 5) 2Th(η 3-H 3BH) 2

    DOE PAGES

    Erickson, Karla A.; Scott, Brian Lindley; Kiplinger, Jaqueline Loetsch

    2017-01-18

    Here, calcium borohydride allows for the high-yielding synthesis of (C 5Me 5)2An(η 3-H 3BH) 2 (An = Th, U) by reaction with (C 5Me 5) 2AnCl 2 (An = Th, U). While a preparative synthesis of (C 5Me 5) 2U(η 3-H 3BH) 2 has been previously reported in the literature using K(C 5Me 5) and U(BH 4) 4, the use of Ca(BH 4) 2 is higher yielding and mild. Full characterization of the novel compound (C 5Me 5) 2Th(η 3-H 3BH) 2 is presented.

  17. Ca(BH 4) 2 as a simple tool for the preparation of thorium and uranium metallocene borohydride complexes: First synthesis and crystal structure of (C 5Me 5) 2Th(η 3-H 3BH) 2

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

    Erickson, Karla A.; Scott, Brian Lindley; Kiplinger, Jaqueline Loetsch

    Here, calcium borohydride allows for the high-yielding synthesis of (C 5Me 5)2An(η 3-H 3BH) 2 (An = Th, U) by reaction with (C 5Me 5) 2AnCl 2 (An = Th, U). While a preparative synthesis of (C 5Me 5) 2U(η 3-H 3BH) 2 has been previously reported in the literature using K(C 5Me 5) and U(BH 4) 4, the use of Ca(BH 4) 2 is higher yielding and mild. Full characterization of the novel compound (C 5Me 5) 2Th(η 3-H 3BH) 2 is presented.

  18. Influence of an iron-rich amendment on chemical lability and plant (Raphanus sativus L.) availability of two metallic elements (As and Pb) on mine-impacted agricultural soils.

    PubMed

    Kim, Juhee; Kim, Yong-Seong; Hyun, Seunghun; Moon, Deok Hyun; Chang, Jun Young

    2016-10-01

    Variation of the chemical extractability and phytoavailability of two metallic elements (e.g., As and Pb) on amendment-treated soils was investigated. Four mine-impacted agricultural soils contaminated with both As (174-491 mg kg -1 ) and Pb (116-357 mg kg -1 ) were amended with an iron-rich sludge at the rate of 5 % (w/w). After a 4-, 8-, and 16-week incubation, the extractability of metallic elements was assessed by sequential extraction procedure (SEP; F1-F5). The control without amendment was also run. In amended soils, the labile element mass (i.e., F1 + F2) promptly decreased (15-48 % of As and 5-10 % of Pb) in 4 weeks, but the decrement was continued over 16 weeks up to 70 and 28 % for As and Pb, respectively. The labile mass decrement was quantitatively corresponded with the increment of F3 (bound to amorphous metal oxides). In plant test assessed by radish (Raphanus sativus) grown on the 16-week soils, up to 57 % of As and 28 % of Pb accumulation was suppressed and 10-43 % of growth (i.e., shoot/root elongation and fresh weight) was improved. For both the control and amended soils, element uptake by plant was well correlated with their labile soil concentrations (r 2  = 0.799 and 0.499 for As and Pb, respectively). The results confirmed that the iron-rich material can effectively suppress element uptake during R. sativus seedling growth, most likely due to the chemical stabilization of metallic elements in growth medium.

  19. Multiconfigurational nature of 5f orbitals in uranium and plutonium intermetallics

    PubMed Central

    Booth, C.H.; Jiang, Yu; Wang, D.L.; Mitchell, J.N.; Tobash, P.H.; Bauer, E.D.; Wall, M.A.; Allen, P.G.; Sokaras, D.; Nordlund, D.; Weng, T.-C.; Torrez, M.A.; Sarrao, J.L.

    2012-01-01

    Uranium and plutonium’s 5f electrons are tenuously poised between strongly bonding with ligand spd-states and residing close to the nucleus. The unusual properties of these elements and their compounds (e.g., the six different allotropes of elemental plutonium) are widely believed to depend on the related attributes of f-orbital occupancy and delocalization for which a quantitative measure is lacking. By employing resonant X-ray emission spectroscopy (RXES) and X-ray absorption near-edge structure (XANES) spectroscopy and making comparisons to specific heat measurements, we demonstrate the presence of multiconfigurational f-orbital states in the actinide elements U and Pu and in a wide range of uranium and plutonium intermetallic compounds. These results provide a robust experimental basis for a new framework toward understanding the strongly-correlated behavior of actinide materials. PMID:22706643

  20. A fluorescence-based bioassay for aquatic macrophytes and its suitability for effect analysis of non-photosystem II inhibitors.

    PubMed

    Küster, Anette; Pohl, Korinna; Altenburger, Rolf

    2007-09-01

    BACKGROUND, GOALS AND SCOPE: During the last years the miniaturization of toxicity test systems for rapid and parallel measurements of large quantities of samples has often been discussed. For unicellular algae as well as for aquatic macrophytes, fluorescence-based miniaturized test systems have been introduced to analyze photosystem II (PSII) inhibitors. Nevertheless, high-throughput screening should also guarantee the effect detection of a broad range of toxicants in order to ensure routinely applicable, high-throughput measuring device experiments which can cover a broad range of toxicants and modes of action others than PSII inhibition. Thus, the aim of this study was to establish a fast and reproducible measuring system for non-PSII inhibitors for aquatic macrophyte species to overcome major limitations for use. A newly developed imaging pulse-amplitude-modulated chlorophyll fluorometer (I-PAM) was applied as an effect detector in short-term bioassays with the aquatic macrophyte species Lemna minor. This multiwell-plate based measuring device enabled the incubation and measurement of up to 24 samples in parallel. The chemicals paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII herbicides, polycyclic aromatic hydrocarbons (PAHs) and pharmaceuticals and personal care products (PPCPs), which are often detected in the aquatic environment. The I-PAM was used (i) to establish and validate the sensitivity of the test system to the three non-PSII inhibitors, (ii) to compare the test systems with standardized and established biotests for aquatic macrophytes, and (iii) to define necessary time scales in aquatic macrophyte testing. For validation of the fluorescence-based assay, the standard growth test with L. minor (ISO/DIS 20079) was performed in parallel for each chemical. The results revealed that fluorescence-based measurements with the I-PAM allow rapid and parallel analysis of large amounts of aquatic macrophyte samples. The I-PAM enabled the recording of concentration-effect-curves with L. minor samples on a 24-well plate with single measurements. Fluorescence-based concentration-effect-curves could be detected for all three chemicals after only 1 h of incubation. After 4-5 h incubation time, the maximum inhibition of fluorescence showed an 80-100% effect for the chemicals tested. The EC50 after 24 h incubation were estimated to be 0.06 mg/L, 0.84 mg/L and 1.69 mg/L for paraquat-dichloride, alizarine and triclosan, respectively. The results obtained with the I-PAM after 24 h for the herbicide paraquat-dichloride and the polycyclic aromatic hydrocarbon alizarine were in good accordance with median effective concentrations (EC50s) obtained by the standardized growth test for L. minor after 7 d incubation (0.09 mg/L and 0.79 mg/L for paraquat-dichloride and alizarine, respectively). Those results were in accordance with literature findings for the two chemicals. In contrast, fluorescence-based EC50 of the antimicrobial agent triclosan proved to be two orders of magnitude greater when compared to the standard growth test with 7 d incubation time (0.026 mg/L) as well as with literature findings. Typically, aquatic macrophyte testing is very time consuming and relies on laborious experimental set-ups. The I-PAM measuring device enabled fast effect screening for the three chemicals tested. While established test systems for aquatic macrophytes need incubation times of > or = 7 d, the I-PAM can detect inhibitory effects much earlier (24 h), even if inhibition of chemicals is not specifically associated with PSII. Thus, the fluorescence-based bioassay with the I-PAM offers a promising approach for the miniaturization and high-throughput testing of chemicals with aquatic macrophytes. For the chemical triclosan, however, the short-term effect prediction with the I-PAM has been shown to be less sensitive than with long-term bioassays, which might be due to physicochemical substance properties such as lipophilicity. The results of this study show that the I-PAM represents a promising tool for decreasing the incubation times of aquatic macrophyte toxicity testing to about 24 h as a supplement to existing test batteries. The applicability of this I-PAM bioassay on emergent and submerged aquatic macrophyte species should be investigated in further studies. Regarding considerations that physicochemical properties of the tested substances might play an important role in microplate bioassays, the I-PAM bioassay should either be accompanied by evaluating physicochemical properties modeled from structural information prior to an experimental investigation, or by intensified chemical analyses to identify and determine nominal concentrations of the toxicants tested. The chemicals paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII herbicides, PAHs and PPCPs which are often detected in the aquatic environment. Nevertheless, in order to ensure a routinely applicable measuring device, experiments with a broader range of toxicants and samples of surface and/or waste waters are necessary.

  1. In Situ Multilength-Scale Tracking of Dimensional and Viscoelastic Changes in Composite Battery Electrodes.

    PubMed

    Dargel, Vadim; Jäckel, Nicolas; Shpigel, Netanel; Sigalov, Sergey; Levi, Mikhael D; Daikhin, Leonid; Presser, Volker; Aurbach, Doron

    2017-08-23

    Intercalation-induced dimensional changes in a composite battery electrode (comprising a polymeric binder) are one of the major factors limiting electrode cycling performance. Since electrode performance is expressed by the quantities averaged over its entire surface area (e.g., capacity retention, Faradaic efficiency, rate capability), significant efforts have been made to develop a methodology allowing its facile mechanical diagnostics at the same areal scale. Herein we introduce such a generic methodology for a highly sensitive in situ monitoring of intrinsic mechanical properties of composite battery electrodes. The gravimetric, dimensional, viscoelastic, and adhesive changes in the composite electrodes caused by Li-ions intercalation are assessed noninvasively and in real time by electrochemical quartz-crystal microbalance with dissipation monitoring (EQCM-D). Multiharmonic acoustic waves generated by EQCM-D penetrate into thin porous electrodes comprising either rigid or a soft binder resulting in frequency and dissipation changes quantified by analytical acoustic load impedance models. As a first demonstration, we used a composite LiFePO 4 (LFP) electrode containing either polyvinylidene dichloride (PVdF) or Na carboximethyl cellulose (NaCMC) as rigid and viscoelastic binders, respectively, in aqueous electrolytes. The intercalation-induced volume changes of LFP electrode were evaluated from a hydrodynamic correction to the mass effect of the intercalated ions for PVdF, and both components of the effective complex shear modulus (i.e., storage and loss moduli) in case of NaCMC binder have been extracted. The sliding friction coefficients for large particles bound at their bottom to the quartz crystal surface (a measure of the adhesion strength of binders) has also been evaluated. Tracking the mechanical properties of the composite electrodes in different environments and charging/cycling conditions in a self-consistent manner provides all necessary conditions for an optimal selection of the polymeric binders resistant to intercalation-induced volume changes of intercalation particles.

  2. Scintillator materials containing lanthanum fluorides

    DOEpatents

    Moses, William W.

    1991-01-01

    An improved radiation detector containing a crystalline mixture of LaF.sub.3 and CeF.sub.3 as the scintillator element is disclosed. Scintillators made with from 25% to 99.5% LaF.sub.3 and the remainder CeF.sub.3 have been found to provide a balance of good stopping power, high light yield and short decay constant that is equal to or superior to other known scintillator materials, and which may be processed from natural starting materials containing both rare earth elements. The radiation detectors disclosed are favorably suited for use in general purpose detection and in positron emission tomography.

  3. Scintillator materials containing lanthanum fluorides

    DOEpatents

    Moses, W.W.

    1991-05-14

    An improved radiation detector containing a crystalline mixture of LaF[sub 3] and CeF[sub 3] as the scintillator element is disclosed. Scintillators made with from 25% to 99.5% LaF[sub 3] and the remainder CeF[sub 3] have been found to provide a balance of good stopping power, high light yield and short decay constant that is equal to or superior to other known scintillator materials, and which may be processed from natural starting materials containing both rare earth elements. The radiation detectors disclosed are favorably suited for use in general purpose detection and in positron emission tomography. 2 figures.

  4. Structure of the Newcastle disease virus F protein in the post-fusion conformation

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

    Swanson, Kurt; Wen, Xiaolin; Leser, George P.

    2010-11-17

    The paramyxovirus F protein is a class I viral membrane fusion protein which undergoes a significant refolding transition during virus entry. Previous studies of the Newcastle disease virus, human parainfluenza virus 3 and parainfluenza virus 5 F proteins revealed differences in the pre- and post-fusion structures. The NDV Queensland (Q) F structure lacked structural elements observed in the other two structures, which are key to the refolding and fusogenic activity of F. Here we present the NDV Australia-Victoria (AV) F protein post-fusion structure and provide EM evidence for its folding to a pre-fusion form. The NDV AV F structure containsmore » heptad repeat elements missing in the previous NDV Q F structure, forming a post-fusion six-helix bundle (6HB) similar to the post-fusion hPIV3 F structure. Electrostatic and temperature factor analysis of the F structures points to regions of these proteins that may be functionally important in their membrane fusion activity.« less

  5. Semiconductor CdF2:Ga and CdF2:In Crystals as Media for Real-Time Holography

    PubMed Central

    Ryskin, Alexander I.; Shcheulin, Alexander S.; Angervaks, Alexander E.

    2012-01-01

    Monocrystalline cadmium fluoride is a dielectric solid that can be converted into a semiconductor by doping with donor impurities and subsequent heating in the reduction atmosphere. For two donor elements, Ga and In, the donor (“shallow”) state is a metastable one separated from the ground (“deep”) state by a barrier. Photoinduced deep-to-shallow state transition underlies the photochromism of CdF2:Ga and CdF2:In. Real-time phase holograms are recorded in these crystals capable of following up optical processes in a wide frequency range. The features of photochromic transformations in CdF2:Ga and CdF2:In crystals as well as holographic characteristics of these media are discussed. Exemplary applications of CdF2-based holographic elements are given. PMID:28817009

  6. Facile solvothermal synthesis of cube-like Ag@AgCl: a highly efficient visible light photocatalyst

    NASA Astrophysics Data System (ADS)

    Han, Lei; Wang, Ping; Zhu, Chengzhou; Zhai, Yueming; Dong, Shaojun

    2011-07-01

    In this paper, a stable and highly efficient plasmonic photocatalyst, Ag@AgCl, with cube-like morphology, has been successfully prepared via a simple hydrothermal method. Using methylene dichloride as chlorine source in the synthesis can efficiently control the morphology of Ag@AgCl, due to the low release rate of chloride ions. Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectra were used to characterize the obtained product. The photocatalytic activity of the obtained product was evaluated by the photodegradation of methyl orange (MO) under visible light irradiation, and it was found, interestingly, that Ag@AgCl exhibits high visible light photocatalytic activity and good stability.In this paper, a stable and highly efficient plasmonic photocatalyst, Ag@AgCl, with cube-like morphology, has been successfully prepared via a simple hydrothermal method. Using methylene dichloride as chlorine source in the synthesis can efficiently control the morphology of Ag@AgCl, due to the low release rate of chloride ions. Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectra were used to characterize the obtained product. The photocatalytic activity of the obtained product was evaluated by the photodegradation of methyl orange (MO) under visible light irradiation, and it was found, interestingly, that Ag@AgCl exhibits high visible light photocatalytic activity and good stability. Electronic supplementary information (ESI) available: SEM images of the AgCl samples synthesized by changing the addition amount of PVP and AgNO3. See DOI: 10.1039/c1nr10247h

  7. 223Ra-dichloride spectrometric characterization: Searching for the presence of long-lived isotopes with radiological protection implications.

    PubMed

    Sánchez-Jiménez, J; López-Montes, A; Núñez-Martínez, L; Villa-Abaunza, A; Fraile, L M; Sánchez-Tembleque, V; Udías, J M

    2017-03-01

    223 Ra-dichloride was approved with the commercial name of Xofigo in 2014 for treatment of metastatic castration-resistant prostate cancer. 223 Ra is obtained by neutron irradiation of 226 Ra yielding 227 Ac, which decays to 227 Th and 223 Fr, both decaying to 223 Ra. Since 223 Ra is predominantly (95.3%) an alpha emitter with a 11.42days long half-life, the radiopharmaceutical, its remnants, the patient, and waste material can be managed and disposed with low radiation protection requirements. 227 Ac is a long-lived (T 1/2 =21.77years) beta emitter that demands strong radiation protection measures. In particular waste disposal has to follow the International Atomic Energy Agency (IAEA) and European Commission (EC) regulations. Since 227 Ac is involved in the production of 223 Ra, an impurity analysis of each batch is required after production. Due to time restrictions, the manufacturer's detection limit (<0.001%) exceeds the one required to assure that 227 Ac concentrations are below direct disposal levels. To improve the detection limit, long-term accurate spectroscopy is required. Alpha and gamma spectroscopy measurements were carried out at the Complutense University Nuclear Physics Laboratory. After twelve months follow up of a sample, 227 Ac concentration was found to be smaller than 10 -9 . This allows for direct waste disposal and no additional radiation protection restrictions than those required for 223 Ra. The presence of contamination by other radioisotopes was also ruled out by this experiment. Specifically 226 Ra, involved in 223 Ra production as the original parent and with a very long-lived (T 1/2 =1577years) alpha emitter, was also below the experimental detection limit. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  8. Modeling focusing characteristics of low Fnumber diffractive optical elements with continuous relief fabricated by laser direct writing.

    PubMed

    Shan, Mingguang; Tan, Jiubin

    2007-12-10

    A theoretical model is established using Rayleigh-Sommerfeld diffraction theory to describe the diffraction focusing characteristics of low F-number diffractive optical elements with continuous relief fabricated by laser direct writing, and continuous-relief diffractive optical elements with a design wavelength of 441.6nm and a F-number of F/4 are fabricated and measured to verify the validity of the diffraction focusing model. The measurements made indicate that the spot size is 1.75mum and the diffraction efficiency is 70.7% at the design wavelength, which coincide well with the theoretical results: a spot size of 1.66mum and a diffraction efficiency of 71.2%.

  9. Supported metallocene catalysts by surface organometallic chemistry. Synthesis, characterization, and reactivity in ethylene polymerization of oxide-supported mono- and biscyclopentadienyl zirconium alkyl complexes: establishment of structure/reactivity relationships.

    PubMed

    Jezequel, M; Dufaud, V; Ruiz-Garcia, M J; Carrillo-Hermosilla, F; Neugebauer, U; Niccolai, G P; Lefebvre, F; Bayard, F; Corker, J; Fiddy, S; Evans, J; Broyer, J P; Malinge, J; Basset, J M

    2001-04-18

    The reactions of CpZr(CH(3))(3), 1, and Cp(2)Zr(CH(3))(2), 2, with partially dehydroxylated silica, silica-alumina, and alumina surfaces have been carried out with careful identification of the resulting surface organometallic complexes in order to probe the relationship between catalyst structure and polymerization activity. The characterization of the supported complexes has been achieved in most cases by in situ infrared spectroscopy, surface microanalysis, qualitative and quantitative analysis of evolved gases during surface reactions with labeled surface, solid state (1)H and (13)C NMR using (13)C-enriched compounds, and EXAFS. 1 and 2 react with silica(500) and silica-alumina(500) by simple protonolysis of one Zr-Me bond by surface silanols with formation of a single well-defined neutral compound. In the case of silica-alumina, a fraction of the supported complexes exhibits some interactions with electronically unsaturated surface aluminum sites. 1 and 2 also react with the hydroxyl groups of gamma-alumina(500), leading to several surface structures. Correlation between EXAFS and (13)C NMR data suggests, in short, two main surface structures having different environments for the methyl group: [Al](3)-OZrCp(CH(3))(2) and [Al](2)-OZrCp(CH(3))(mu-CH(3))-[Al] for the monoCp series and [Al](2)-OZrCp(2)(CH(3)) and [Al]-OZrCp(2)(mu-CH(3))-[Al] for the bisCp series. Ethylene polymerization has been carried out with all the supported complexes under various reaction conditions. Silica-supported catalysts in the absence of any cocatalyst exhibited no activity whatsoever for ethylene polymerization. When the oxide contained Lewis acidic sites, the resulting surface species were active. The activity, although improved by the presence of additional cocatalysts, remained very low by comparison with that of the homogeneous metallocene systems. This trend has been interpreted on the basis of various possible parameters, including the (p-pi)-(d-pi) back-donation of surface oxygen atoms to the zirconium center.

  10. Polymer Dehalogenation-Enabled Fast Fabrication of N,S-Codoped Carbon Materials for Superior Supercapacitor and Deionization Applications.

    PubMed

    Chang, Yingna; Zhang, Guoxin; Han, Biao; Li, Haoyuan; Hu, Cejun; Pang, Yingchun; Chang, Zheng; Sun, Xiaoming

    2017-09-06

    Doped carbon materials (DCM) with multiple heteroatoms hold broad interest in electrochemical catalysis and energy storage but require several steps to fabricate, which greatly hinder their practical applications. In this study, a facile strategy is developed to enable the fast fabrication of multiply doped carbon materials via room-temperature dehalogenation of polyvinyl dichloride (PVDC) promoted by KOH with the presence of different organic dopants. A N,S-codoped carbon material (NS-DCM) is demonstratively synthesized using two dopants (dimethylformamide for N doping and dimethyl sulfoxide for S doping). Afterward, the precursive room-temperature NS-DCM with intentionally overdosed KOH is submitted to inert annealing to obtain large specific surface area and high conductivity. Remarkably, NS-DCM annealed at 600 °C (named as 600-NS-DCM), with 3.0 atom % N and 2.4 atom % S, exhibits a very high specific capacitance of 427 F g -1 at 1.0 A g -1 in acidic electrolyte and also keeps ∼60% of capacitance at ultrahigh current density of 100.0 A g -1 . Furthermore, capacitive deionization (CDI) measurements reveal that 600-NS-DCM possesses a large desalination capacity of 32.3 mg g -1 (40.0 mg L -1 NaCl) and very good cycling stability. Our strategy of fabricating multiply doped carbon materials can be potentially extended to the synthesis of carbon materials with various combinations of heteroatom doping for broad electrochemical applications.

  11. Direct and converse theorems in problems of approximation by vectors of finite degree

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

    Radzievski, G V

    1998-04-30

    Let A be a linear operator in a complex Banach space X with domain D(A) and a non-empty resolvent set. An element g element of D{sub {infinity}}(A):= intersection{sub j=0,1,...}D(A{sup j}) is called a vector of degree at most {zeta}(>0) with respect to A if ||A{sup j}g||{sub X}{<=}c(g){zeta}{sup j}, j=0,1,.... The set of vectors of degree at most {zeta} is denoted by G{sub {zeta}}(A). The quantity E{sub {zeta}}(f,A){sub X}=inf{sub gelement} {sub of{sub G}{sub {zeta}}}{sub (A)}||f-g||{sub X} is introduced and estimated in terms of the K-functional K({zeta}{sup -r},f;X,D(A{sup r}))=inf{sub gelementof} {sub D(A{sup r})}(||f-g||{sub X}+{zeta}{sup -r}||A{sup r}f||{sub X}) (the direct theorem). An estimatemore » of this K-functional in terms of E{sub {zeta}}(f,A){sub X} and ||f||{sub x} is established (the converse theorem). Using the estimates obtained, necessary and sufficient conditions for the following properties are found in terms of E{sub {zeta}}(f,A){sub X}: 1) f element of D{sub {infinity}}(A); 2) the series e{sup zA}f:={sigma}{sub r=0}{sup {infinity}}(z{sup r}A{sup r}f)/(r{exclamation_point}) converges in some disc; 3) the series e{sup zA}f converges in the entire complex plane. The growth order and the type of the entire function e{sup zA}f are calculated in terms of E{sub {zeta}}(f,A){sub X}.« less

  12. Metal-metal bonds in f-element chemistry.

    PubMed

    Liddle, Stephen T; Mills, David P

    2009-08-07

    The molecular chemistry of the f-elements is traditionally dominated by the use of carbon-, nitrogen-, oxygen-, or halide-ligands. However, the use of metal-based fragments as ligands is underdeveloped, which contrasts to the fields of d- and p-block metal-metal complexes that have developed extensively over the last fifty years. This perspective outlines the development of compounds, which possess polarised covalent or donor-acceptor f-element-metal bonds. For this review, the f-element is defined as (i) a group 3 or lanthanide metal: scandium, yttrium, lanthanum to lutetium, or (ii) an actinide metal: thorium, or uranium, and the metal is defined as a d-block transition metal, or a group 13 (aluminium or gallium), a group 14 (silicon, germanium, or tin), or a group 15 (antimony, or bismuth) metal. Silicon, germanium, and antimony are traditionally classified as metalloids but they are included for completeness. This review focuses mainly on complexes that have been structurally authenticated by single-crystal X-ray diffraction studies and we highlight novel aspects of their syntheses, properties, and reactivities.

  13. Research of Ionospheric Scintillation in Asia (RISA)

    DTIC Science & Technology

    2014-03-01

    5a. CONTRACT NUMBER FA2386-11-1-4087 5b. GRANT NUMBER Grant AOARD-114087 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Dr Nitin...11-1-4087 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Nitin Kumar Tripathi 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK...anomaly, as these locations experience the strongest global levels of scintillation (Groves et al., 1997). As a result, large quantities of data sets

  14. Creation of half-metallic f -orbital Dirac fermion with superlight elements in orbital-designed molecular lattice

    NASA Astrophysics Data System (ADS)

    Cui, Bin; Huang, Bing; Li, Chong; Zhang, Xiaoming; Jin, Kyung-Hwan; Zhang, Lizhi; Jiang, Wei; Liu, Desheng; Liu, Feng

    2017-08-01

    Magnetism in solids generally originates from the localized d or f orbitals that are hosted by heavy transition-metal elements. Here, we demonstrate a mechanism for designing a half-metallic f -orbital Dirac fermion from superlight s p elements. Combining first-principles and model calculations, we show that bare and flat-band-sandwiched (FBS) Dirac bands can be created when C20 molecules are deposited into a two-dimensional hexagonal lattice, which are composed of f -molecular orbitals (MOs) derived from s p -atomic orbitals (AOs). Furthermore, charge doping of the FBS Dirac bands induces spontaneous spin polarization, converting the system into a half-metallic Dirac state. Based on this discovery, a model of a spin field effect transistor is proposed to generate and transport 100% spin-polarized carriers. Our finding illustrates a concept to realize exotic quantum states by manipulating MOs, instead of AOs, in orbital-designed molecular crystal lattices.

  15. The ability of the Coincidence Doppler Broadening Spectroscopy to characterize polymers containing different chemical elements

    NASA Astrophysics Data System (ADS)

    Yang, J.; Zhang, T.; Han, L. A.; Cao, X. Z.; Yu, R. S.; Wang, B. Y.

    2017-04-01

    Hydrocarbon polymers, O-containing, F-containing and Cl-containing polymers are comprehensively studied by Coincidence Doppler Broadening Spectroscopy (CDBS). It is shown that for polymers with different chemical structure, CDBS results can effectively distinguish polar groups C dbnd O, Csbnd Cl, and Csbnd F. For polymers with similar chemical structure, the intensity of the element-specific peak in the CDBS ratio curve is dependent not only on the fraction of free positrons, but also on the content of characteristic atom in polymer repeated unit, and the polarity of the polymer molecule. For polymers containing several different polar groups, such as PCTFE (Csbnd F & Csbnd Cl) and PFA (Csbnd F & C dbnd O), whether the element-specific peak appears or not depends on the amount of the polar groups and its positron capture ability. This work may provide insights into potential applications of CDBS for studying complex polymer systems.

  16. Manual for automatic generation of finite element models of spiral bevel gears in mesh

    NASA Technical Reports Server (NTRS)

    Bibel, G. D.; Reddy, S.; Kumar, A.

    1994-01-01

    The goal of this research is to develop computer programs that generate finite element models suitable for doing 3D contact analysis of faced milled spiral bevel gears in mesh. A pinion tooth and a gear tooth are created and put in mesh. There are two programs: Points.f and Pat.f to perform the analysis. Points.f is based on the equation of meshing for spiral bevel gears. It uses machine tool settings to solve for an N x M mesh of points on the four surfaces, pinion concave and convex, and gear concave and convex. Points.f creates the file POINTS.OUT, an ASCI file containing N x M points for each surface. (N is the number of node points along the length of the tooth, and M is nodes along the height.) Pat.f reads POINTS.OUT and creates the file tl.out. Tl.out is a series of PATRAN input commands. In addition to the mesh density on the tooth face, additional user specified variables are the number of finite elements through the thickness, and the number of finite elements along the tooth full fillet. A full fillet is assumed to exist for both the pinion and gear.

  17. Testing and evaluation of Vespel up to 450 deg F when used in nuts and bolts as a self-locking element

    NASA Technical Reports Server (NTRS)

    Wood, C. M.

    1984-01-01

    The object of this investigation was to evaluate Vespel for potential application on the Solid Rocket Booster to replace all-metal deformed self-locking nuts and anchor nuts and be used as self-locking elements for bolts and screws. The Vespel self-locking elements were tested for prevailing torque retention at room temperature, after heating to 450 F and exposure for 3 hr, breakaway torque at 450 F and for vibration at a level consistent with the maximum expected on the SRB at lift-off and reentry. The investigation revealed Vespel has properties that can provide a self-locking capability for threaded fasteners up to 450 F and it can be used in nuts and anchor nuts for installation on the SRB. Vespel elements in bolts did not meet all our SRB requirements for reuse, however, we have defined a design for Vespel elements in nuts/anchor nuts that fully meets all requirements. It is recommended that No. 1, 1/4 in. and 5/16 in. nuts/anchor nuts be procured for use on the SRB. This system will eliminate the galling problems now encountered and achieve a much higher reuse life than the present deformed nut design.

  18. Quantitative assessment of metal elements using moss species as biomonitors in downwind area of lead-zinc mine.

    PubMed

    Balabanova, Biljana; Stafilov, Trajče; Šajn, Robert; Andonovska, Katerina Bačeva

    2017-02-23

    Distributions of a total of 21 elements were monitored in significantly lead-zinc polluted area using moss species (Hypnum cupressiforme and Camptothecium lutescens) used interchangeably, covering a denser sampling network. Interspecies comparison was conducted using Box-Cox transformed values, due to their skewed distribution. The median concentrations of trace elements in the both mosses examined decreased in the following order: Fe>Mn>Zn>Pb>Cu>Ni∼Cr∼As>Co>Cd>Hg. For almost all analyzed elements, H. cupressiforme revealed higher bio-accumulative abilities. For arsenic contents was obtained ER-value in favor of C. lutescens. The ER for the element contents according to the distance from the pollution source in selected areas was significantly enriched for the anthropogenic introduced elements As, Cd, Cu, Pb and Zn. After Box-Cox transformation of the content values, T B was significantly different for As (4.82), Cd (3.84), Cu (2.95), Pb (4.38), and Zn (4.23). Multivariate factor analysis singled out four elemental associations: F1 (Al-Co-Cr-Fe-Li-Ni-V), F2 (Cd-Pb-Zn), F3 (Ca-Mg-Na-P) and F4 (Cu) with a total variance of 89%. Spatial distribution visualized the hazardously higher contents of "hot spots" of Cd > 1.30 mg/kg, Cu > 22 mg/kg, Pb > 130 mg/kg and Zn > 160 mg/kg. Therefore, main approach in moss biomonitoring should be based on data management of the element distribution by reducing the effect of extreme values (considering Box-Cox data transformation); the interspecies variation in sampling media does not deviate in relation to H. cupressiforme vs. C. lutescens.

  19. Energy Transfer between Post-Transition Elements & Rare Earths in Oxide & Chalcogenide Glasses.

    DTIC Science & Technology

    1979-08-27

    Caird [13]. A calculation of reduced matrix elements of Pr3 in 20 Na O • 80 TeO2 glass [14] showed that they differ slightly from data of ref. [121... glasses Transition (lass 35 ZnO 65 TeO2 20 Na2 O 80 TeO 2 fX 106 fX 106 l.,eas 3a, a) Ia’l. faI f.me.s f al f+ I fal 3 H4 - 3 H6 1.56 1.65 1.12...Rare-Earth Doped Glasses 20. jIST HAEV CCnFn~m ,i cn,on ra e sideit If c."*Ar’ -- ~ 14-r by t?-h.c .: r Intensity parameters, radiative transition

  20. Production test IP-376-D, Supplement B Irradiation of MGCR-HDR-3 Test Element

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

    Baars, R.E.

    The objective of this supplement to PT-IP-376-D, Irradiation of MGCR-HDR-3 Test Element is to authorize 1000 hours of operation at a maximum test specimen surface temperature of 1700 F. The original production test authorized a test duration of four months at a maximum specimen surface temperature of 1500 F; supplement A authorized extension of the test duration to ten months. The desired increase in surface temperature is requested to demonstrate the general feasibility of operation of the fuel element at 1700 F, and to obtain specific information on the performance of Hastelloy-X cladding and fuel bodies. The increased temperature hasmore » been approved by the Atomic Energy Commission.« less

  1. Binding of group 15 and group 16 oxides by a concave host containing an isophthalamide unit.

    PubMed

    Eckelmann, Jens; Saggiomo, Vittorio; Fischmann, Svenja; Lüning, Ulrich

    2012-01-01

    A bi-macrocycle with an incorporated isophthalamide substructure was synthesized by double amide formation between an isophthaloyl dichloride and two equivalents of a bis(alkenyloxy)aniline, followed by ring-closing metathesis and hydrogenation. In contrast to many related isophthalamides, the concave host exhibits a better binding for oxides, such as DMSO or pyridine-N-oxide, than for halide anions. A general method for a quick estimation of the strength of binding derived from only a few data points is presented and gives an estimated K(ass) of pyridine-N-oxide of ca. 40 M(-1), NMR titration confirms 25 M(-1).

  2. Study of efficacy of reactivator HI 6 in reactivation of immobilized acetylcholinesterase, inhibited by organophosphorus chemical warfare agents of the "G" series.

    PubMed

    Hoskovcová, Monika; Halámek, Emil; Kobliha, Zbynĕk

    2009-01-01

    Reactivation with bis quaternary aldoxime HI-6, chemical formula 1-(2-hydroxyamino-methylpyridinium)-3-(4-carbamoylpyridinium)-2-oxapropane dichloride of immobilized enzyme acetylcholinesterase inhibited by nerve agent type "G" was studied. This aldoxime is effective in reactivation of sarin-inhibited acetylcholinesterase. Substantially lower reactivation potency was observed with cyclosarin-inhibited enzyme and almost no effect was found for that acetylcholinesterase is the enzyme complex. HI 6 is completely ineffective towards the soman-inhibited enzyme: After a 2-minute inhibition of the enzyme with soman no ability to define reactivator the inhibited enzymes and complexes.

  3. Polyamide microcapsules containing jojoba oil prepared by inter-facial polymerization.

    PubMed

    Persico, P; Carfagna, C; Danicher, L; Frere, Y

    2005-08-01

    Jojoba oil containing polyamide microcapsules having diameter of approximately 5 microm were prepared by inter-facial polycondensation by direct method (oil-in-water). Qualitative effects of both the formulation and the process parameters on microcapsules characteristics were investigated by SEM observations. Morphological analysis showed the dependence of the external membrane compactness on the chemical nature of the water-soluble polyamine and the oil-soluble acid polychloride: 1,6-hexamethylenediamine (HMDA) and terephthaloyl dichloride (TDC) were found to favour the production of smooth and dense surfaces. The use of ultrasonic irradiations during the dispersion step to get a further reduction of microcapsules size was also evaluated.

  4. Sodium-metal chloride batteries

    NASA Technical Reports Server (NTRS)

    Ratnakumar, B. V.; Attia, A. I.; Halpert, G.

    1992-01-01

    It was concluded that rapid development in the technology of sodium metal chloride batteries has been achieved in the last decade mainly due to the: expertise available with sodium sulfur system; safety; and flexibility in design and fabrication. Long cycle lives of over 1000 and high energy densities of approx. 100 Wh/kg have been demonstrated in both Na/FeCl2 and Na/NiCl2 cells. Optimization of porous cathode and solid electrolyte geometries are essential for further enhancing the battery performance. Fundamental studies confirm the capabilities of these systems. Nickel dichloride emerges as the candidate cathode material for high power density applications such as electric vehicle and space.

  5. The Effect of Risk Factors on the Levels of Chemical Elements in the Tibial Plateau of Patients with Osteoarthritis following Knee Surgery.

    PubMed

    Lanocha-Arendarczyk, Natalia; Kosik-Bogacka, Danuta Izabela; Prokopowicz, Adam; Kalisinska, Elzbieta; Sokolowski, Sebastian; Karaczun, Maciej; Zietek, Pawel; Podlasińska, Joanna; Pilarczyk, Bogumila; Tomza-Marciniak, Agnieszka; Baranowska-Bosiacka, Irena; Gutowska, Izabela; Safranow, Krzysztof; Chlubek, Dariusz

    2015-01-01

    The aim of this study was to evaluate the aforementioned chemical elements in tibial plateau samples obtained during knee arthroplasty. The gender-specific analysis of chemical element levels in the bone samples revealed that there were statistically significant differences in the concentration of Pb and Se/Pb ratio. The contents of elements in the tibial plateau in the patients with osteoarthritis (OA) can be arranged in the following descending order: F(-) > K > Zn > Fe > Sr > Pb > Mn > Se > Cd > THg. We observed statistical significant effects of environmental factors including smoking, seafood diet, and geographical distribution on the levels of the elements in tibial bone. Significant positive correlation coefficients were found for the relationships K-Cd, Zn-Sr, Zn-F(-), THg-Pb, Pb-Cd, Se-Se/Pb, Se-Se/Cd, Se/Pb-Se/Cd, Pb-Cd/Ca, Cd-Cd/Ca, and F(-)-F(-)/Ca·1000. Significant negative correlations were found for the relationships THg-Se/Pb, Pb-Se/Pb, Cd-Se/Pb, K-Se/Cd, Pb-Se/Cd, Cd-Se/Cd, THg-Se/THg, Pb-Se/THg, Se-Pb/Cd, Zn-Cd/Ca, and Se/Cd-Cd/Ca. The results reported here may provide a basis for establishing reference values for the tibial plateau in patients with OA who had undergone knee replacement surgery. The concentrations of elements in the bone with OA were determined by age, presence of implants, smoking, fish and seafood diet, and sport activity.

  6. The first row anomaly and recoupled pair bonding in the halides of the late p-block elements.

    PubMed

    Dunning, Thom H; Woon, David E; Leiding, Jeff; Chen, Lina

    2013-02-19

    The dramatic differences between the properties of molecules formed from the late p-block elements of the first row of the periodic table (N-F) and those of the corresponding elements in subsequent rows is well recognized as the first row anomaly. Certain properties of the atoms, such as the relative energies and spatial extents of the ns and np orbitals, can explain some of these differences, but not others. In this Account, we summarize the results of our recent computational studies of the halides of the late p-block elements. Our studies point to a single underlying cause for many of these differences: the ability of the late p-block elements in the second and subsequent rows of the periodic table to form recoupled pair bonds and recoupled pair bond dyads with very electronegative ligands. Recoupled pair bonds form when an electron in a singly occupied ligand orbital recouples the pair of electrons in a doubly occupied lone pair orbital on the central atom, leading to a central atom-ligand bond. Recoupled pair bond dyads occur when a second ligand forms a bond with the orbital left over from the initial recoupled pair bond. Recoupled pair bonds and recoupled pair bond dyads enable the late p-block elements to form remarkably stable hypervalent compounds such as PF(5) and SF(6) and lead to unexpected excited states in smaller halides of the late p-block elements such as SF and SF(2). Recoupled pair bonding also causes the F(n-1)X-F bond energies to oscillate dramatically once the normal valences of the central atoms have been satisfied. In addition, recoupled pair bonding provides a lower-energy pathway for inversion in heavily fluorinated compounds (PF(3) and PF(2)H, but not PH(2)F and PH(3)) and leads to unusual intermediates and products in reactions involving halogens and late p-block element compounds, such as (CH(3))(2)S + F(2). Although this Account focuses on the halides of the second row, late p-block elements, recoupled pair bonds and recoupled pair bond dyads are important in the chemistry of p-block elements beyond the second row (As, Se, and Br) and for compounds of these elements with other very electronegative ligands, such as OH and O. Knowledge of recoupled pair bonding is thus critical to understanding the properties and reactivity of molecules containing the late p-block elements beyond the first row.

  7. Optimal least-squares finite element method for elliptic problems

    NASA Technical Reports Server (NTRS)

    Jiang, Bo-Nan; Povinelli, Louis A.

    1991-01-01

    An optimal least squares finite element method is proposed for two dimensional and three dimensional elliptic problems and its advantages are discussed over the mixed Galerkin method and the usual least squares finite element method. In the usual least squares finite element method, the second order equation (-Delta x (Delta u) + u = f) is recast as a first order system (-Delta x p + u = f, Delta u - p = 0). The error analysis and numerical experiment show that, in this usual least squares finite element method, the rate of convergence for flux p is one order lower than optimal. In order to get an optimal least squares method, the irrotationality Delta x p = 0 should be included in the first order system.

  8. Atmospheric emissions of F, As, Se, Hg, and Sb from coal-fired power and heat generation in China.

    PubMed

    Chen, Jian; Liu, Guijian; Kang, Yu; Wu, Bin; Sun, Ruoyu; Zhou, Chuncai; Wu, Dun

    2013-02-01

    Coal is one of the major energy resources in China, with nearly half of produced Chinese coal used for power and heat generation. The large use of coal for power and heat generation in China may result in significant atmospheric emissions of toxic volatile trace elements (i.e. F, As, Se, Hg, and Sb). For the purpose of estimating the atmospheric emissions from coal-fired power and heat generation in China, a simple method based on coal consumption, concentration and emission factor of trace element was adopted to calculate the gaseous emissions of elements F, As, Se, Hg, and Sb. Results indicate that about 162161, 236, 637, 172, and 33 t F, As, Se, Hg, and Sb, respectively, were introduced into atmosphere from coal combustion by power and heat generation in China in 2009. The atmospheric emissions of F, As, Se, Hg, and Sb by power and heat generation increased from 2005 to 2009 with increasing coal consumptions. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  9. EBP1 is a novel E2F target gene regulated by transforming growth factor-β.

    PubMed

    Judah, David; Chang, Wing Y; Dagnino, Lina

    2010-11-10

    Regulation of gene expression requires transcription factor binding to specific DNA elements, and a large body of work has focused on the identification of such sequences. However, it is becoming increasingly clear that eukaryotic transcription factors can exhibit widespread, nonfunctional binding to genomic DNA sites. Conversely, some of these proteins, such as E2F, can also modulate gene expression by binding to non-consensus elements. E2F comprises a family of transcription factors that play key roles in a wide variety of cellular functions, including survival, differentiation, activation during tissue regeneration, metabolism, and proliferation. E2F factors bind to the Erb3-binding protein 1 (EBP1) promoter in live cells. We now show that E2F binding to the EBP1 promoter occurs through two tandem DNA elements that do not conform to typical consensus E2F motifs. Exogenously expressed E2F1 activates EBP1 reporters lacking one, but not both sites, suggesting a degree of redundancy under certain conditions. E2F1 increases the levels of endogenous EBP1 mRNA in breast carcinoma and other transformed cell lines. In contrast, in non-transformed primary epidermal keratinocytes, E2F, together with the retinoblastoma family of proteins, appears to be involved in decreasing EBP1 mRNA abundance in response to growth inhibition by transforming growth factor-β1. Thus, E2F is likely a central coordinator of multiple responses that culminate in regulation of EBP1 gene expression, and which may vary depending on cell type and context.

  10. Thyroid functions and trace elements in pediatric patients with exogenous obesity.

    PubMed

    Cayir, Atilla; Doneray, Hakan; Kurt, Nezahat; Orbak, Zerrin; Kaya, Avni; Turan, Mehmet Ibrahim; Yildirim, Abdulkadir

    2014-02-01

    Obesity is a multifactorial disease developing following impairment of the energy balance. The endocrine system is known to be affected by the condition. Serum thyroid hormones and trace element levels have been shown to be affected in obese children. Changes in serum thyroid hormones may result from alterations occurring in serum trace element levels. The aim of this study was to evaluate whether or not changes in serum thyroid hormone levels in children with exogenous obesity are associated with changes in trace element levels. Eighty-five children diagnosed with exogenous obesity constituted the study group, and 24 age- and sex-matched healthy children made up the control group. Serum thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), thyroglobulin (TG), selenium (Se), zinc (Zn), copper (Cu), and manganese (Mn) levels in the study group were measured before and at the third and sixth months of treatment, and once only in the control group. Pretreatment fT4 levels in the study group rose significantly by the sixth month (p = 0.006). Zn levels in the patient group were significantly low compared to the control group (p = 0.009). Mn and Se levels in the obese children before and at the third and sixth months of treatment were significantly higher than those of the control group (p = 0.001, p = 0.001). In conclusion, fT4, Zn, Cu, Mn, and Se levels are significantly affected in children diagnosed with exogenous obesity. The change in serum fT4 levels is not associated with changes in trace element concentrations.

  11. 40 CFR 61.123 - Emission testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Elemental Phosphorus Plants § 61.123 Emission testing. (a) Each owner or operator of an elemental phosphorus... conducted within 45 days under these conditions. (f) Each owner or operator of an elemental phosphorus plant...

  12. 40 CFR 61.123 - Emission testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Elemental Phosphorus Plants § 61.123 Emission testing. (a) Each owner or operator of an elemental phosphorus... conducted within 45 days under these conditions. (f) Each owner or operator of an elemental phosphorus plant...

  13. Taking Proof based Verified Computation a Few Steps Closer to Practicality (extended version)

    DTIC Science & Technology

    2012-06-27

    general s2 + s, in general V’s per-instance CPU costs Issue commit queries (e + 2c) · n/β (e + 2c) · n/β Process commit responses d d Issue PCP...size (# of instances) (§2.3) e: cost of encrypting an element in F d : cost of decrypting an encrypted element f : cost of multiplying in F h: cost of...domain D (such as the integers, Z, or the rationals, Q) to equivalent constraints over a finite field, the programmer or compiler performs 3We suspect

  14. Geometrically Nonlinear Analysis of Shell Structures Using Flat DKT Shell Elements.

    DTIC Science & Technology

    1985-11-22

    In general 1r is a curved surface and the exact expressions of f1 e I are not simpler than f e 1. In fact they are theorically identical when the...1982. [23] Zienkiewicz, 0. C., The Finite Element Method (3rd Edition), McGraw-Hill, 1977. [24] Bergan, P. G., Holand , I., Soreide, T. H., "Use of

  15. Trace Elements Speciation of Submicron Particulate Matter (PM1) Collected in the Surroundings of Power Plants.

    PubMed

    Zajusz-Zubek, Elwira; Kaczmarek, Konrad; Mainka, Anna

    2015-10-16

    This study reports the concentrations of PM1 trace elements (As, Cd, Co, Cr, Hg, Mn, Ni, Pb, Sb and Se) content in highly mobile (F1), mobile (F2), less mobile (F3) and not mobile (F4) fractions in samples that were collected in the surroundings of power plants in southern Poland. It also reports source identification by enrichment factors (EF) and a principal component analysis (PCA). There is limited availability of scientific data concerning the chemical composition of dust, including fractionation analyses of trace elements, in the surroundings of power plants. The present study offers important results in order to fill this data gap. The data collected in this study can be utilized to validate air quality models in this rapidly developing area. They are also crucial for comparisons with datasets from similar areas all over the world. Moreover, the identification of the bioavailability of selected carcinogenic and toxic elements in the future might be used as output data for potential biological and population research on risk assessment. This is important in the context of air pollution being hazardous to human health.

  16. ERalpha and AP-1 interact in vivo with a specific sequence of the F promoter of the human ERalpha gene in osteoblasts.

    PubMed

    Lambertini, Elisabetta; Tavanti, Elisa; Torreggiani, Elena; Penolazzi, Letizia; Gambari, Roberto; Piva, Roberta

    2008-07-01

    Estrogen-responsive genes often have an estrogen response element (ERE) positioned next to activator protein-1 (AP-1) binding sites. Considering that the interaction between ERE and AP-1 elements has been described for the modulation of bone-specific genes, we investigated the 17-beta-estradiol responsiveness and the role of these cis-elements present in the F promoter of the human estrogen receptor alpha (ERalpha) gene. The F promoter, containing the sequence analyzed here, is one of the multiple promoters of the human ERalpha gene and is the only active promoter in bone tissue. Through electrophoretic mobility shift (EMSA), chromatin immunoprecipitation (ChIP), and re-ChIP assays, we investigated the binding of ERalpha and four members of the AP-1 family (c-Jun, c-fos, Fra-2, and ATF2) to a region located approximately 800 bp upstream of the transcriptional start site of exon F of the human ERalpha gene in SaOS-2 osteoblast-like cells. Reporter gene assay experiments in combination with DNA binding assays demonstrated that F promoter activity is under the control of upstream cis-acting elements which are recognized by specific combinations of ERalpha, c-Jun, c-fos, and ATF2 homo- and heterodimers. Moreover, ChIP and re-ChIP experiments showed that these nuclear factors bind the F promoter in vivo with a simultaneous occupancy stimulated by 17-beta-estradiol. Taken together, our findings support a model in which ERalpha/AP-1 complexes modulate F promoter activity under conditions of 17-beta-estradiol stimulation. (c) 2008 Wiley-Liss, Inc.

  17. Regulation of ecmF gene expression and genetic hierarchy among STATa, CudA, and MybC on several prestalk A-specific gene expressions in Dictyostelium.

    PubMed

    Saga, Yukika; Inamura, Tomoka; Shimada, Nao; Kawata, Takefumi

    2016-05-01

    STATa, a Dictyostelium homologue of metazoan signal transducer and activator of transcription, is important for the organizer function in the tip region of the migrating Dictyostelium slug. We previously showed that ecmF gene expression depends on STATa in prestalk A (pstA) cells, where STATa is activated. Deletion and site-directed mutagenesis analysis of the ecmF/lacZ fusion gene in wild-type and STATa null strains identified an imperfect inverted repeat sequence, ACAAATANTATTTGT, as a STATa-responsive element. An upstream sequence element was required for efficient expression in the rear region of pstA zone; an element downstream of the inverted repeat was necessary for sufficient prestalk expression during culmination. Band shift analyses using purified STATa protein detected no sequence-specific binding to those ecmF elements. The only verified upregulated target gene of STATa is cudA gene; CudA directly activates expL7 gene expression in prestalk cells. However, ecmF gene expression was almost unaffected in a cudA null mutant. Several previously reported putative STATa target genes were also expressed in cudA null mutant but were downregulated in STATa null mutant. Moreover, mybC, which encodes another transcription factor, belonged to this category, and ecmF expression was downregulated in a mybC null mutant. These findings demonstrate the existence of a genetic hierarchy for pstA-specific genes, which can be classified into two distinct STATa downstream pathways, CudA dependent and independent. The ecmF expression is indirectly upregulated by STATa in a CudA-independent activation manner but dependent on MybC, whose expression is positively regulated by STATa. © 2016 Japanese Society of Developmental Biologists.

  18. Calculation of Collisional Cross Sections for the 2P3/2 - 2P1/2 Transition in Alkali-Noble Gas Systems

    DTIC Science & Technology

    2010-03-01

    matrix elements. From scattering matrix elements for several different effective potential values and using the Method of Partial Waves[7], the...scattering matrix elements. Through the Method of Par- tial Waves[7], the procedure was repeated for several different effective potentials. The...section calculations. It is important to note that lmax may differ for σel and σi→f . This method may only be used if both σi→f and σel have

  19. Statistical Inference on Optimal Points to Evaluate Multi-State Classification Systems

    DTIC Science & Technology

    2014-09-18

    vs2+ ( dbcm3 ˆ 2 ) *vm3+( dbcs3 ˆ 2 ) * vs3 80 VETA <−VBCA+VBC EETA<−EBCA−EBC 82 W<− (EETA−TV) / s q r t ( VETA ) # T e s t p−v a l u e − t o compare t o a...event set, E = (ε1, ε2, ..., εk) to k distinct elements of a label set, L = (l1, l2, ..., lk) . These partitions may be referred to as classes. For...set of features, F = ( f1, f2, ..., fm) . These features are then used to assign the different elements from E to the respective labels, L , (A : E → F

  20. Microbial synthesis of Flower-shaped gold nanoparticles.

    PubMed

    Singh, Priyanka; Kim, Yeon Ju; Wang, Chao; Mathiyalagan, Ramya; Yang, Deok Chun

    2016-09-01

    The shape of nanoparticles has been recognized as an important attribute that determines their applicability in various fields. The flower shape (F-shape) has been considered and is being focused on, because of its enhanced properties when compared to the properties of the spherical shape. The present study proposed the microbial synthesis of F-shaped gold nanoparticles within 48 h using the Bhargavaea indica DC1 strain. The F-shaped gold nanoparticles were synthesized extracellularly by the reduction of auric acid in the culture supernatant of B. indica DC1. The shape, size, purity, and crystalline nature of F-shaped gold nanoparticles were revealed by various instrumental techniques including UV-Vis, FE-TEM, EDX, elemental mapping, XRD, and DLS. The UV-Vis absorbance showed a maximum peak at 536 nm. FE-TEM revealed the F-shaped structure of nanoparticles. The EDX peak obtained at 2.3 keV indicated the purity. The peaks obtained on XRD analysis corresponded to the crystalline nature of the gold nanoparticles. In addition, the results of elemental mapping indicated the maximum distribution of gold elements in the nanoproduct obtained. Particle size analysis revealed that the average diameter of the F-shaped gold nanoparticles was 106 nm, with a polydispersity index (PDI) of 0.178. Thus, the methodology developed for the synthesis of F-shaped gold nanoparticles is completely green and economical.

  1. Excimer laser beam delivery systems for medical applications

    NASA Astrophysics Data System (ADS)

    Kubo, Uichi; Hashishin, Yuichi; Okada, Kazuyuki; Tanaka, Hiroyuki

    1993-05-01

    We have been doing the basic experiments of UV laser beams and biotissue interaction with both KrF and XeCl lasers. However, the conventional optical fiber can not be available for power UV beams. So we have been investigating about UV power beam delivery systems. These experiments carry on with the same elements doped quartz fibers and the hollow tube. The doped elements are OH ion, chlorine and fluorine. In our latest work, we have tried ArF excimer laser and biotissue interactions, and the beam delivery experiments. From our experimental results, we found that the ArF laser beam has high incision ability for hard biotissue. For example, in the case of the cow's bone incision, the incision depth by ArF laser was ca.15 times of KrF laser. Therefore, ArF laser would be expected to harden biotissue therapy as non-thermal method. However, its beam delivery is difficult to work in this time. We will develop ArF laser beam delivery systems.

  2. Synthesis of (±)-amathaspiramide F and discovery of an unusual stereocontrolling element for the [2,3]-Stevens rearrangement.

    PubMed

    Soheili, Arash; Tambar, Uttam K

    2013-10-04

    A formal total synthesis of (±)-amathaspiramide F through a tandem palladium-catalyzed allylic amination/[2,3]-Stevens rearrangement is reported. The unexpected diastereoselectivity of the [2,3]-Stevens rearrangement was controlled by the substitution patterns of an aromatic ring. This discovery represents a new stereocontrolling element for [2,3]-sigmatropic rearrangements in complex molecular settings.

  3. Microarray and comparative genomics-based identification of genes and gene regulatory regions of the mouse immune system

    PubMed Central

    Hutton, John J; Jegga, Anil G; Kong, Sue; Gupta, Ashima; Ebert, Catherine; Williams, Sarah; Katz, Jonathan D; Aronow, Bruce J

    2004-01-01

    Background In this study we have built and mined a gene expression database composed of 65 diverse mouse tissues for genes preferentially expressed in immune tissues and cell types. Using expression pattern criteria, we identified 360 genes with preferential expression in thymus, spleen, peripheral blood mononuclear cells, lymph nodes (unstimulated or stimulated), or in vitro activated T-cells. Results Gene clusters, formed based on similarity of expression-pattern across either all tissues or the immune tissues only, had highly significant associations both with immunological processes such as chemokine-mediated response, antigen processing, receptor-related signal transduction, and transcriptional regulation, and also with more general processes such as replication and cell cycle control. Within-cluster gene correlations implicated known associations of known genes, as well as immune process-related roles for poorly described genes. To characterize regulatory mechanisms and cis-elements of genes with similar patterns of expression, we used a new version of a comparative genomics-based cis-element analysis tool to identify clusters of cis-elements with compositional similarity among multiple genes. Several clusters contained genes that shared 5–6 cis-elements that included ETS and zinc-finger binding sites. cis-Elements AP2 EGRF ETSF MAZF SP1F ZF5F and AREB ETSF MZF1 PAX5 STAT were shared in a thymus-expressed set; AP4R E2FF EBOX ETSF MAZF SP1F ZF5F and CREB E2FF MAZF PCAT SP1F STAT cis-clusters occurred in activated T-cells; CEBP CREB NFKB SORY and GATA NKXH OCT1 RBIT occurred in stimulated lymph nodes. Conclusion This study demonstrates a series of analytic approaches that have allowed the implication of genes and regulatory elements that participate in the differentiation, maintenance, and function of the immune system. Polymorphism or mutation of these could adversely impact immune system functions. PMID:15504237

  4. Multivariate analyses of Erzgebirge granite and rhyolite composition: Implications for classification of granites and their genetic relations

    USGS Publications Warehouse

    Forster, H.-J.; Davis, J.C.; Tischendorf, G.; Seltmann, R.

    1999-01-01

    High-precision major, minor and trace element analyses for 44 elements have been made of 329 Late Variscan granitic and rhyolitic rocks from the Erzgebirge metallogenic province of Germany. The intrusive histories of some of these granites are not completely understood and exposures of rock are not adequate to resolve relationships between what apparently are different plutons. Therefore, it is necessary to turn to chemical analyses to decipher the evolution of the plutons and their relationships. A new classification of Erzgebirge plutons into five major groups of granites, based on petrologic interpretations of geochemical and mineralogical relationships (low-F biotite granites; low-F two-mica granites; high-F, high-P2O5 Li-mica granites; high-F, low-P2O5 Li-mica granites; high-F, low-P2O5 biotite granites) was tested by multivariate techniques. Canonical analyses of major elements, minor elements, trace elements and ratio variables all distinguish the groups with differing amounts of success. Univariate ANOVA's, in combination with forward-stepwise and backward-elimination canonical analyses, were used to select ten variables which were most effective in distinguishing groups. In a biplot, groups form distinct clusters roughly arranged along a quadratic path. Within groups, individual plutons tend to be arranged in patterns possibly reflecting granitic evolution. Canonical functions were used to classify samples of rhyolites of unknown association into the five groups. Another canonical analysis was based on ten elements traditionally used in petrology and which were important in the new classification of granites. Their biplot pattern is similar to that from statistically chosen variables but less effective at distinguishing the five groups of granites. This study shows that multivariate statistical techniques can provide significant insight into problems of granitic petrogenesis and may be superior to conventional procedures for petrological interpretation.

  5. Synthesis and characterization of a new and electronically unusual uranium metallacyclocumulene, (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph)

    DOE PAGES

    Pagano, Justin K.; Erickson, Karla A.; Scott, Brian L.; ...

    2016-10-22

    A new uranium metallacyclocumulene, (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph), was synthesized by both reaction of (C 5Me 5) 2UCl 2 with 1,4-diphenylbutadiyne in the presence of KC 8 and by ligand exchange between (C 5Me 5) 2U(η 2-Me 3SiC 2SiMe 3) and 1,4-diphenylbutadiyne. Lastly, full characterization of (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph) is reported, including the solid-state structure. (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph) displays an unusually detailed UV–visible spectrum, which is rare for uranium(IV) metallocene complexes.

  6. Synthesis and characterization of a new and electronically unusual uranium metallacyclocumulene, (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph)

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

    Pagano, Justin K.; Erickson, Karla A.; Scott, Brian L.

    A new uranium metallacyclocumulene, (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph), was synthesized by both reaction of (C 5Me 5) 2UCl 2 with 1,4-diphenylbutadiyne in the presence of KC 8 and by ligand exchange between (C 5Me 5) 2U(η 2-Me 3SiC 2SiMe 3) and 1,4-diphenylbutadiyne. Lastly, full characterization of (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph) is reported, including the solid-state structure. (C 5Me 5) 2U(η 4-1,2,3,4-PhC 4Ph) displays an unusually detailed UV–visible spectrum, which is rare for uranium(IV) metallocene complexes.

  7. Are Some Elements More Equal than Others?

    ERIC Educational Resources Information Center

    Rich, Ronald L.

    2005-01-01

    Squeezing of elements 57-71 and 89-103 into one box each something like footnotes is done. A periodic chart is needed that does not treat the f elements as mere footnotes, partly because some like Uranium are quite important.

  8. Fatigue Characterization of Alloy 10: a 1300F Disk Alloy for Small Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    Gayda, John

    2000-01-01

    A detailed fatigue characterization of Alloy 10, a high strength nickel-based disk alloy, was conducted on test coupons machined from a 'pancake' forging. Smooth bar, strain controlled fatigue testing at various R-ratios was run at representative bore, 750 F, and rim, 1300 F, temperatures. This was followed by notch fatigue testing (Kt=2) run under load control. Analysis of the fatigue data using a Smith-Watson-Topper approach and finite element analysis of the notch root was employed to understand material behavior in these tests. Smooth bar fatigue data showed a significant R-ratio dependence at either test temperature which could be accounted for using a Smith-Watson-Topper parameter (SWT). In general, fatigue life was longer at 750 F than 1300 F for a given SWT. For notch fatigue tests, life was longer at 750 F than 1300 F but only at higher stresses. This was attributed to differences in alloy strength. At lower stresses, finite element analysis suggested that convergence of fatigue life at both temperatures resulted from relaxation of stresses at the notch root in the 1300 F tests.

  9. Contact-independent electrical conductance measurement

    DOEpatents

    Mentzel, Tamar S.; MacLean, Kenneth; Kastner, Marc A.; Ray, Nirat

    2017-01-24

    Electrical conductance measurement system including a one-dimensional semiconducting channel, with electrical conductance sensitive to electrostatic fluctuations, in a circuit for measuring channel electrical current. An electrically-conductive element is disposed at a location at which the element is capacitively coupled to the channel; a midpoint of the element aligned with about a midpoint of the channel, and connected to first and second electrically-conductive contact pads that are together in a circuit connected to apply a changing voltage across the element. The electrically-conductive contact pads are laterally spaced from the midpoint of the element by a distance of at least about three times a screening length of the element, given in SI units as (K.di-elect cons..sub.0/e.sup.2D(E.sub.F)).sup.1/2, where K is the static dielectric constant, .di-elect cons..sub.0 is the permittivity of free space, e is electron charge, and D(E.sub.F) is the density of states at the Fermi energy for the element.

  10. Statistical Methods in Physical Oceanography: Proceedings of ’Aha Huliko’a Hawaiian Winter Workshop Held in Manoa, Hawaii on January 12-15, 1993

    DTIC Science & Technology

    1993-11-01

    field X(t) at time 1. Ti. is the set of all times when both pi and pi have been observed and ni. is the number of elements in T Definition Eq. (22) is...termed contour analysis, for melding of oceanic data and for space-time interpolation of gappy frontal data sets . The key elements of contour analysis...plane and let fl(1) be the set of all straight lines intersecting F. Directly measuring the number of intersections between a random element W E 11(F) and

  11. Effect of additives on the volatility of elements in a DC arc during the atomic emission analysis of nickel(II) oxide

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

    Zolotareva, N.I.; Kuzyakov, Yu.Ya.; Khlystova, A.D.

    1986-10-20

    The authors have studied the effect of traditional halogenating additives, AgCl, CdF/sub 2/, PTFE and that of an effective additive they have selected, ZnF/sub 2/, on the volatility of impurity elements, viz. tungsten, molybdenum, titanium, and zirconium from nickel (II) oxide, and determined the constants for the average relative volatility of the elements by the method of Kantor and Pungor. The results have been used to lower the limits of detection of the impurities cited in nickel(II) oxide.

  12. Binding of group 15 and group 16 oxides by a concave host containing an isophthalamide unit

    PubMed Central

    Eckelmann, Jens; Saggiomo, Vittorio; Fischmann, Svenja

    2012-01-01

    Summary A bi-macrocycle with an incorporated isophthalamide substructure was synthesized by double amide formation between an isophthaloyl dichloride and two equivalents of a bis(alkenyloxy)aniline, followed by ring-closing metathesis and hydrogenation. In contrast to many related isophthalamides, the concave host exhibits a better binding for oxides, such as DMSO or pyridine-N-oxide, than for halide anions. A general method for a quick estimation of the strength of binding derived from only a few data points is presented and gives an estimated K ass of pyridine-N-oxide of ca. 40 M−1, NMR titration confirms 25 M−1. PMID:22423268

  13. Transformation of regioregular organotitanium polymers into group 16 heterole-containing π-conjugated materials.

    PubMed

    Nishiyama, Hiroki; Kino, Tomoko; Tomita, Ikuyoshi

    2012-04-13

    Regioregular organometallic polymers with titanacyclopentadiene units, obtained from terminal diynes and a low-valent titanium complex, were subjected to reactions with disulfur dichloride and selenium (I) chloride to give π-conjugated polymers with thiophene and selenophene units in the main chain in 63% and 86% yields. Their number-average molecular weights were estimated as 4300 and 5700, respectively. Both polymers were found to be fully π-conjugated and their HOMO energy levels were remarkably high (-5.3 eV and -5.0 eV for thiophene- and selenophene-containing polymers, respectively) as supported by their UV-vis absorption spectra and CV analyses. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Rapid thin-layer chromatographic photodensitometric method for the determination of metoclopramide and clebopride in the presence of some of their metabolic products.

    PubMed

    Huizing, G; Beckett, A H; Segura, J

    1979-04-21

    Metoclopramide and its newly developed analogue clebopride, together with some of their metabolic products are quantitated, following extraction from biological tissues and fluids, and subsequent separation on silica gel thin-layer chromatographic plates. Diazotisation, followed by coupling with N-(1-naphthyl)ethylenediammonium dichloride, carried out on the thin-layer plate, is utilised for visualisation. The intensity of the spots is measured by photodensitometric analysis. The effect of variation of various experimental conditions is studied. The method has proven to be satisfactory for the measurement of 20 ng/ml of these compounds in biological material; the results are well within the accepted limits of deviation.

  15. Photographic combustion characterization of LOX/Hydrocarbon type propellants

    NASA Technical Reports Server (NTRS)

    Judd, D. C.

    1980-01-01

    One hundred twenty-seven tests were conducted over a chamber pressure range of 125-1500 psia, a fuel temperature range of -245 F to 158 F, and a fuel velocity range of 48-707 ft/sec to demonstrate the advantages and limitations of using high speed photography to identify potential combustion anomalies such as pops, fuel freezing, reactive stream separation and carbon formations. Combustion evaluation criteria were developed to guide selection of the fuels, injector elements, and operating conditions for testing. Separate criteria were developed for fuel and injector element selection and evaluation. The photographic test results indicated conclusively that injector element type and design directly influence carbon formation. Unlike spray fan, impingement elements reduce carbon formation because they induce a relatively rapid near zone fuel vaporization rate. Coherent jet impingement elements, on the other hand, exhibit increased carbon formation.

  16. Apatite/Melt Partitioning Experiments Reveal Redox Sensitivity to Cr, V, Mn, Ni, Eu, W, Th, and U

    NASA Technical Reports Server (NTRS)

    Righter, K.; Yang, S.; Humayun, M.

    2016-01-01

    Apatite is a common mineral in terrestrial, planetary, and asteroidal materials. It is commonly used for geochronology (U-Pb), sensing volatiles (H, F, Cl, S), and can concentrate rare earth elements (REE) during magmatic fractionation and in general. Some recent studies have shown that some kinds of phosphate may fractionate Hf and W and that Mn may be redox sensitive. Experimental studies have focused on REE and other lithophile elements and at simplified or not specified oxygen fugacities. There is a dearth of partitioning data for chalcophile, siderophile and other elements between apatite and melt. Here we carry out several experiments at variable fO2 to study the partitioning of a broad range of trace elements. We compare to existing data and then focus on several elements that exhibit redox dependent partitioning behavior.

  17. Solid Lubricated Rolling Element Bearings

    DTIC Science & Technology

    1979-02-15

    lubricant into uneven patches of varnish . This varnish , along with the file-like action of the exposed ball carbides on the relatively softer races, can...its structure. Fluorine , one of the most reactive elements, reacts with graphite without combustion from about 790’F to 1022°F, forming a grey-colored...to allow for molding and machining after molding. 0 Method 2 (Hughes) Impregnating these dense weaves with a Thermid 600 polyimide varnish

  18. Evaluation of dietary exposure to minerals, trace elements and heavy metals from the muscle tissue of the lionfish Pterois volitans (Linnaeus 1758).

    PubMed

    Hoo Fung, Leslie A; Antoine, Johann M R; Grant, Charles N; Buddo, Dayne St A

    2013-10-01

    Twenty-five samples of Pterois volitans caught in Jamaican waters were analyzed for 25 essential, non-essential and toxic elements using Graphite Furnace Atomic Absorption Spectrophotometry (GF-AAS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Instrumental Neutron Activation Analysis (INAA). The mean values for calcium (355 mg/kg), copper (107 μg/kg), iron (0.81 mg/kg), potassium (3481 mg/kg), magnesium (322 mg/kg), manganese (0.04 mg/kg), selenium (0.47 mg/kg), sodium (700 mg/kg) and zinc (4.46 mg/kg) were used to estimate dietary intake. The percentage contribution to provisional tolerable weekly intake for a 70 kg male and a 65 kg female were also estimated for the toxic elements arsenic (1.28% M, 1.38% F), cadmium (0.26% M. 0.28% F), mercury (3.85% M, 4.15% F) and lead (0.17% M, 0.18% F). To further assess the risk of mercury toxicity and the role of mitigation provided by selenium, selenium-mercury molar ratios were calculated for all samples. All samples were shown to have a molar excess of selenium. In addition the suggested selenium health benefit value was calculated, and was positive for all samples. It was concluded that P. volitans appears to contribute modestly to mineral and trace element nutrition, while not being a significant contributor to dietary exposure of toxic elements. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Elemental abundance analyses with DAO spectrograms: XXXII. HR 6455 (A3 III), δ Aqr (A3 V), η Lep (F2 V), and 1 Boo (A1 V)

    NASA Astrophysics Data System (ADS)

    Yüce, K.; Adelman, S. J.; Gulliver, A. F.; Hill, G.

    2011-08-01

    We examine the sharp-lined stars HR 6455 (A3 III, v sin i = 8.7 km s-1) and η Lep (F2 V, v sin i = 13.5 km s-1) as well as δ Aqr (A3 V, v sin i = 81 km s-1) and 1 Boo (A1 V, v sin i = 59 km s-1) to increase the number consistently analyzed A and F stars using high dispersion and high S/N (≥200) spectrograms obtained with CCD detectors at the long Coudé camera of the 1.22-m telescope of the Dominion Astrophysical Observatory. Such studies contribute to understanding systematic abundance differences between normal and non-magnetic main-sequence band chemically peculiar A and early F stars. LTE fine analyses of HR 6455, δ Aqr, and 1 Boo using Kurucz's ATLAS suite programs show the same general elemental abundance trends with differences in the metal richness. Light and iron-peak element abundances are generally solar or overabundant while heavy element and rare earth element abundances are overabundant. HR 6455 is an evolved Am star while δ Aqr and 1 Boo show the phenomenon to different extents. Most derived abundances of η Lep are solar. Table 3 is available at the CDS via http://cdsarc.u-strasbg.fr/cgi-bin/qcat?J/AN/332/681

  20. [Molecular-genetic analysis of wheat (T. aestivum L.) genome with introgression of Ae. cylindrica Host genetic elements].

    PubMed

    Galaev, A V; Sivolap, Iu M

    2005-01-01

    Wheat-aegilops hybrid plants Triticum aestivum L. (2n = 42) x Aegilops cylindrica Host (2n = 28) were investigated with using microsatellite markers. In two BC1F9 lines some genome modifications connected with losing DNA fragments of initial variety or appearing of Aegilops genome elements were detected. In some investigated hybrids new amplicons lacking in parental plants were found. Substitution of wheat chromosomes for aegilops chromosomes was not revealed. Analysis of microsatellite loci in BC2F5 plants showed stable introgression of aegilops genetic elements into wheat; elimination of some transferred aegilops DNA fragments in the course of backcrossing; decreasing size of introgressive elements after backcrossing. Introgressive lines were classified according to genome changes.

  1. 43 CFR 4.1307 - Elements; burdens of proof.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Elements; burdens of proof. 4.1307 Section... Review of Proposed Individual Civil Penalty Assessments Under Section 518(f) of the Act § 4.1307 Elements... individual shall have the ultimate burden of persuasion by a preponderance of the evidence as to the elements...

  2. 43 CFR 4.1307 - Elements; burdens of proof.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Elements; burdens of proof. 4.1307 Section... Review of Proposed Individual Civil Penalty Assessments Under Section 518(f) of the Act § 4.1307 Elements... individual shall have the ultimate burden of persuasion by a preponderance of the evidence as to the elements...

  3. 43 CFR 4.1307 - Elements; burdens of proof.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Elements; burdens of proof. 4.1307 Section... Review of Proposed Individual Civil Penalty Assessments Under Section 518(f) of the Act § 4.1307 Elements... individual shall have the ultimate burden of persuasion by a preponderance of the evidence as to the elements...

  4. 43 CFR 4.1307 - Elements; burdens of proof.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Elements; burdens of proof. 4.1307 Section... Review of Proposed Individual Civil Penalty Assessments Under Section 518(f) of the Act § 4.1307 Elements... individual shall have the ultimate burden of persuasion by a preponderance of the evidence as to the elements...

  5. 43 CFR 4.1307 - Elements; burdens of proof.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Elements; burdens of proof. 4.1307 Section... Review of Proposed Individual Civil Penalty Assessments Under Section 518(f) of the Act § 4.1307 Elements... individual shall have the ultimate burden of persuasion by a preponderance of the evidence as to the elements...

  6. Research on the relationship between the elements and pharmacological activities in velvet antler using factor analysis and cluster analysis

    NASA Astrophysics Data System (ADS)

    Zhou, Libing

    2017-04-01

    Velvet antler has certain effect on improving the body's immune cells and the regulation of immune system function, nervous system, anti-stress, anti-aging and osteoporosis. It has medicinal applications to treat a wide range of diseases such as tissue wound healing, anti-tumor, cardiovascular disease, et al. Therefore, the research on the relationship between pharmacological activities and elements in velvet antler is of great significance. The objective of this study was to comprehensively evaluate 15 kinds of elements in different varieties of velvet antlers and study on the relationship between the elements and traditional Chinese medicine efficacy for the human. The factor analysis and the factor cluster analysis methods were used to analyze the data of elements in the sika velvet antler, cervus elaphus linnaeus, flower horse hybrid velvet antler, apiti (elk) velvet antler, male reindeer velvet antler and find out the relationship between 15 kinds of elements including Ca, P, Mg, Na, K, Fe, Cu, Mn, Al, Ba, Co, Sr, Cr, Zn and Ni. Combining with MATLAB2010 and SPSS software, the chemometrics methods were made on the relationship between the elements in velvet antler and the pharmacological activities. The first commonality factor F1 had greater load on the indexes of Ca, P, Mg, Co, Sr and Ni, and the second commonality factor F2 had greater load on the indexes of K, Mn, Zn and Cr, and the third commonality factor F3 had greater load on the indexes of Na, Cu and Ba, and the fourth commonality factor F4 had greater load on the indexes of Fe and Al. 15 kinds of elements in velvet antler in the order were elk velvet antler>flower horse hybrid velvet antler>cervus elaphus linnaeus>sika velvet antler>male reindeer velvet antler. Based on the factor analysis and the factor cluster analysis, a model for evaluating traditional Chinese medicine quality was constructed. These studies provide the scientific base and theoretical foundation for the future large-scale rational relation development of velvet antler resources as well as the relationship between the elements and traditional Chinese medicine efficacy for the human.

  7. Synthesis and reactivity of bis(tetramethylcyclopentadienyl) yttrium metallocenes including the reduction of Me(3)SiN(3) to [(Me(3)Si)(2)N](-) with [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)).

    PubMed

    Lorenz, Sara E; Schmiege, Benjamin M; Lee, David S; Ziller, Joseph W; Evans, William J

    2010-07-19

    The metallocene precursors needed to provide the tetramethylcyclopentadienyl yttrium complexes (C(5)Me(4)H)(3)Y, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)), and [(C(5)Me(4)H)(2)Y(mu-H)](2) for reactivity studies have been synthesized and fully characterized, and their reaction chemistry has led to an unexpected conversion of an azide to an amide. (C(5)Me(4)H)(2)Y(mu-Cl)(2)K(THF)(x), 1, synthesized from YCl(3) and KC(5)Me(4)H reacts with allylmagnesium chloride to make (C(5)Me(4)H)(2)Y(eta(3)-C(3)H(5)), 2, which is converted to [(C(5)Me(4)H)(2)Y][(mu-Ph)(2)BPh(2)], 3, with [Et(3)NH][BPh(4)]. Complex 3 reacts with KC(5)Me(4)H to form (C(5)Me(4)H)(3)Y, 4. The reduced dinitrogen complex, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-N(2)), 5, can be synthesized from either [(C(5)Me(4)H)(2)Y](2)[(mu-Ph)(2)BPh(2)], 3, or (C(5)Me(4)H)(3)Y, 4, with potassium graphite under a dinitrogen atmosphere. The (15)N labeled analogue, [(C(5)Me(4)H)(2)Y(THF)](2)(mu-eta(2):eta(2)-(15)N(2)), 5-(15)N, has also been prepared, and the (15)N NMR data have been compared to previously characterized reduced dinitrogen complexes. Complex 2 reacts with H(2) to form the corresponding hydride, [(C(5)Me(4)H)(2)Y(mu-H)](2), 6. Complex 5 displays similar reactivity to that of the analogous [(C(5)Me(4)H)(2)Ln(THF)](2)(mu-eta(2):eta(2)-N(2)) complexes (Ln = La, Lu), with substrates such as phenazine, anthracene, and CO(2). In addition, 5 reduces Me(3)SiN(3) to form (C(5)Me(4)H)(2)Y[N(SiMe(3))(2)], 7.

  8. Oil-in-oil emulsions: a unique tool for the formation of polymer nanoparticles.

    PubMed

    Klapper, Markus; Nenov, Svetlin; Haschick, Robert; Müller, Kevin; Müllen, Klaus

    2008-09-01

    Polymer latex particles are nanofunctional materials with widespread applications including electronics, pharmaceuticals, photonics, cosmetics, and coatings. These materials are typically prepared using waterborne heterogeneous systems such as emulsion, miniemulsion, and suspension polymerization. However, all of these processes are limited to water-stable catalysts and monomers mainly polymerizable via radical polymerization. In this Account, we describe a method to overcome this limitation: nonaqueous emulsions can serve as a versatile tool for the synthesis of new types of polymer nanoparticles. To form these emulsions, we first needed to find two nonmiscible nonpolar/polar aprotic organic solvents. We used solvent mixtures of either DMF or acetonitrile in alkanes and carefully designed amphiphilic block and statistical copolymers, such as polyisoprene- b-poly(methyl methacrylate) (PI- b-PMMA), as additives to stabilize these emulsions. Unlike aqueous emulsions, these new emulsion systems allowed the use of water-sensitive monomers and catalysts. Although polyaddition and polycondensation reactions usually lead to a large number of side products and only to oligomers in the aqueous phase, these new conditions resulted in high-molecular-weight, defect-free polymers. Furthermore, conducting nanoparticles were produced by the iron(III)-induced synthesis of poly(ethylenedioxythiophene) (PEDOT) in an emulsion of acetonitrile in cyclohexane. Because metallocenes are sensitive to nitrile and carbonyl groups, the acetonitrile and DMF emulsions were not suitable for carrying out metallocene-catalyzed olefin polymerization. Instead, we developed a second system, which consists of alkanes dispersed in perfluoroalkanes. In this case, we designed a new amphipolar polymeric emulsifier with fluorous and aliphatic side chains to stabilize the emulsions. Such heterogeneous mixtures facilitated the catalytic polymerization of ethylene or propylene to give spherical nanoparticles of high molecular weight polyolefins. These nonaqueous systems also allow for the combination of different polymerization techniques to obtain complex architectures such as core-shell structures. Previously, such structures primarily used vinylic monomers, which greatly limited the number of polymer combinations. We have demonstrated how nonaqueous emulsions allow the use of a broad variety of hydrolyzable monomers and sensitive catalysts to yield polyester, polyurethane, polyamide, conducting polymers, and polyolefin latex particles in one step under ambient reaction conditions. This nonpolar emulsion strategy dramatically increases the chemical palette of polymers that can form nanoparticles via emulsion polymerization.

  9. Elastic Behavior of a Rubber Layer Bonded between Two Rigid Spheres.

    DTIC Science & Technology

    1988-05-01

    Cracking, Composites, Compressibility, Def ormition, Dilatancy, Elasticity, Elastomers , Failure, Fracture, Particle ’,-1tr1f6rcement, Rubber, Stress...Analysis. 2.AITRACT (Ca~mmi ON VOW...lds It 񔨾Y MtE fIdnt & bp04 bo ambwe - Finite element methods ( FEM ) have been employed to calculate the stresses...deformations set up by compression or extension of the layer, using finite element methods ( FEM ) and not invoking the condition of incompressibility

  10. Transition metals in superheat melts

    NASA Technical Reports Server (NTRS)

    Jakes, Petr; Wolfbauer, Michael-Patrick

    1993-01-01

    A series of experiments with silicate melts doped with transition element oxides was carried out at atmospheric pressures of inert gas at temperatures exceeding liquidus. As predicted from the shape of fO2 buffer curves in T-fO2 diagrams the reducing conditions for a particular oxide-metal pair can be achieved through the T increase if the released oxygen is continuously removed. Experimental studies suggest that transition metals such as Cr or V behave as siderophile elements at temperatures exceeding liquidus temperatures if the system is not buffered by the presence of other oxide of more siderophile element. For example the presence of FeO prevents the reduction of Cr2O3. The sequence of decreasing siderophility of transition elements at superheat conditions (Mo, Ni, Fe, Cr) matches the decreasing degree of depletion of siderophile elements in mantle rocks as compared to chondrites.

  11. Asteroid orbital inversion using uniform phase-space sampling

    NASA Astrophysics Data System (ADS)

    Muinonen, K.; Pentikäinen, H.; Granvik, M.; Oszkiewicz, D.; Virtanen, J.

    2014-07-01

    We review statistical inverse methods for asteroid orbit computation from a small number of astrometric observations and short time intervals of observations. With the help of Markov-chain Monte Carlo methods (MCMC), we present a novel inverse method that utilizes uniform sampling of the phase space for the orbital elements. The statistical orbital ranging method (Virtanen et al. 2001, Muinonen et al. 2001) was set out to resolve the long-lasting challenges in the initial computation of orbits for asteroids. The ranging method starts from the selection of a pair of astrometric observations. Thereafter, the topocentric ranges and angular deviations in R.A. and Decl. are randomly sampled. The two Cartesian positions allow for the computation of orbital elements and, subsequently, the computation of ephemerides for the observation dates. Candidate orbital elements are included in the sample of accepted elements if the χ^2-value between the observed and computed observations is within a pre-defined threshold. The sample orbital elements obtain weights based on a certain debiasing procedure. When the weights are available, the full sample of orbital elements allows the probabilistic assessments for, e.g., object classification and ephemeris computation as well as the computation of collision probabilities. The MCMC ranging method (Oszkiewicz et al. 2009; see also Granvik et al. 2009) replaces the original sampling algorithm described above with a proposal probability density function (p.d.f.), and a chain of sample orbital elements results in the phase space. MCMC ranging is based on a bivariate Gaussian p.d.f. for the topocentric ranges, and allows for the sampling to focus on the phase-space domain with most of the probability mass. In the virtual-observation MCMC method (Muinonen et al. 2012), the proposal p.d.f. for the orbital elements is chosen to mimic the a posteriori p.d.f. for the elements: first, random errors are simulated for each observation, resulting in a set of virtual observations; second, corresponding virtual least-squares orbital elements are derived using the Nelder-Mead downhill simplex method; third, repeating the procedure two times allows for a computation of a difference for two sets of virtual orbital elements; and, fourth, this orbital-element difference constitutes a symmetric proposal in a random-walk Metropolis-Hastings algorithm, avoiding the explicit computation of the proposal p.d.f. In a discrete approximation, the allowed proposals coincide with the differences that are based on a large number of pre-computed sets of virtual least-squares orbital elements. The virtual-observation MCMC method is thus based on the characterization of the relevant volume in the orbital-element phase space. Here we utilize MCMC to map the phase-space domain of acceptable solutions. We can make use of the proposal p.d.f.s from the MCMC ranging and virtual-observation methods. The present phase-space mapping produces, upon convergence, a uniform sampling of the solution space within a pre-defined χ^2-value. The weights of the sampled orbital elements are then computed on the basis of the corresponding χ^2-values. The present method resembles the original ranging method. On one hand, MCMC mapping is insensitive to local extrema in the phase space and efficiently maps the solution space. This is somewhat contrary to the MCMC methods described above. On the other hand, MCMC mapping can suffer from producing a small number of sample elements with small χ^2-values, in resemblance to the original ranging method. We apply the methods to example near-Earth, main-belt, and transneptunian objects, and highlight the utilization of the methods in the data processing and analysis pipeline of the ESA Gaia space mission.

  12. Molecular beam epitaxy growth of SmFeAs(O,F) films with Tc = 55 K using the new fluorine source FeF3

    NASA Astrophysics Data System (ADS)

    Sakoda, Masahito; Ishii, Akihiro; Takinaka, Kenji; Naito, Michio

    2017-07-01

    REFeAs(O,F) (RE: rare-earth element) has the highest-Tc (˜58 K) among the iron-based superconductors, but a thin-film growth of REFeAs(O,F) is difficult. This is because it is not only a complex compound consisting of five elements but also requires doping of highly reactive fluorine to achieve superconductivity. We have reported in our previous article that fluorine can be supplied to a film by subliming solid-state fluorides such as FeF2 or SmF3. In this article, we report on the growth of SmFeAs(O,F) using FeF3 as an alternative fluorine source. FeF3 is solid at ambient temperatures and decomposes at temperatures as low as 100-200 °C, and releases fluorine-containing gas during the thermal decomposition. With this alternative fluorine source, we have grown SmFeAs(O,F) films with Tc as high as 55 K. This achievement demonstrates that FeF3 has potential as a fluorine source that can be employed ubiquitously for a thin-film growth of any fluorine containing compounds. One problem specific to FeF3 is that the compound is highly hydroscopic and contains a substantial amount of water even in its anhydrous form. In this article, we describe how to overcome this specific problem.

  13. Reaction of tin(iv) phthalocyanine dichloride with decamethylmetallocenes (M = CrII and CoII). Strong magnetic coupling of spins in (Cp*2Co+){SnIVCl2(Pc˙3-)}˙-·2C6H4Cl2.

    PubMed

    Konarev, Dmitri V; Troyanov, Sergey I; Shestakov, Alexander F; Yudanova, Evgeniya I; Otsuka, Akihiro; Yamochi, Hideki; Kitagawa, Hiroshi; Lyubovskaya, Rimma N

    2018-01-23

    The reaction of tin(iv) phthalocyanine dichloride {Sn IV Cl 2 (Pc 2- )} with decamethylmetallocenes (Cp* 2 M, M = Co, Cr) has been studied. Decamethylcobaltocene reduces Sn IV Cl 2 (Pc 2- ) to form the (Cp* 2 Co + ){Sn IV Cl 2 (Pc˙ 3- )}˙ - ·2C 6 H 4 Cl 2 (1) complex. The negative charge of {Sn IV Cl 2 (Pc˙ 3- )}˙ - is delocalized over the Pc macrocycle providing the alternation of the C-N(imine) bonds, the appearance of new bands in the NIR range and a strong blue shift of both the Soret and Q-bands in the spectrum of 1. The magnetic moment of 1 is equal to 1.68μ B at 300 K, indicating the contribution of one S = 1/2 spin of the Pc˙ 3- macrocycles. These macrocycles form closely packed double stacks in 1 with effective π-π interactions providing strong antiferromagnetic coupling of spins at a Weiss temperature of -80 K. Decamethylchromocene initially also reduces Sn IV Cl 2 (Pc 2- ) to form the [(Cp* 2 Cr + ){Sn VI Cl 2 (Pc˙ 3- )}˙ - complex but further reaction between the ions is observed. This reaction is accompanied by the substitution of one Cp* ligand of Cp* 2 Cr by chloride anions originating from {Sn IV Cl 2 (Pc˙ 3- )}˙ - to form the complex {(Cp*CrCl 2 )(Sn IV (μ-Cl)(Pc 2- ))}·C 6 H 4 Cl 2 (2) in which the (Cp*CrCl 2 ) and {Sn IV (Pc 2- )} species are bonded through the μ-bridged Cl - anion. According to the DFT calculations, this reaction proceeds via an intermediate [(Cp* 2 CrCl)(SnClPc)] complex.

  14. Partitioning of Moderately Siderophile Elements Among Olivine, Silicate Melt, and Sulfide Melt: Constraints on Core Formation in the Earth and Mars

    NASA Technical Reports Server (NTRS)

    Gaetani, Glenn A.; Grove, Timothy L.

    1997-01-01

    This study investigates the effects of Variations in the fugacities of oxygen and sulfur on the partitioning of first series transition metals (V, Cr, Mn, Fe, Co, Ni. and Cu) and W among coexisting sulfide melt, silicate melt, and olivine. Experiments were performed at 1 atm pressure, 1350 C, with the fugacities of oxygen and sulfur controlled by mixing CO2, CO, and SO2 gases. Starting compositions consisted of a CaO-MgO-Al2O3-SiO2-FeO-Na2O analog for a barred olivine chondrule from an ordinary chondrite and a synthetic komatiite. The f(sub O2)/f(sub S2), conditions ranged from log of f(sub O2) = -7.9 to - 10.6, with log of f(sub S2) values ranging from - 1.0 to -2.5. Our experimental results demonstrate that the f(sub O2)/f(sub S2) dependencies of sulfide melt/silicate melt partition coefficients for the first series transition metals arc proportional to their valence states. The f(sub O2)/f(sub S2) dependencies for the partitioning of Fe, Co, Ni, and Cu are weaker than predicted on the basis of their valence states. Variations in conditions have no significant effect on olivine/melt partitioning other than those resulting from f(sub O2)-induced changes in the valence state of a given element. The strong f(sub O2)/f(sub S2) dependence for the olivine/silicate melt partitioning of V is attributable to a change of valence state, from 4+ to 3+, with decreasing f(sub O2). Our experimentally determined partition coefficients are used to develop models for the segregation of sulfide and metal from the silicate portion of the early Earth and the Shergottite parent body (Mars). We find that the influence of S is not sufficient to explain the overabundance of siderophile and chalcophile elements that remained in the mantle of the Earth following core formation. Important constraints on core formation in Mars are provided by our experimental determination of the partitioning of Cu between silicate and sulfide melts. When combined with existing estimates for siderophile element abundances in the Martian mantle and a mass balance constraint from Fe, the experiments allow a determination of the mass of the Martian core (approx. 17 to 22 wt% of the planet) and its S content (approx.0.4 wt%). These modeling results indicate that Mars is depleted in S, and that its core is solid.

  15. A suggested periodic table up to Z≤ 172, based on Dirac-Fock calculations on atoms and ions.

    PubMed

    Pyykkö, Pekka

    2011-01-07

    Extended Average Level (EAL) Dirac-Fock calculations on atoms and ions agree with earlier work in that a rough shell-filling order for the elements 119-172 is 8s < 5g≤ 8p(1/2) < 6f < 7d < 9s < 9p(1/2) < 8p(3/2). The present Periodic Table develops further that of Fricke, Greiner and Waber [Theor. Chim. Acta 1971, 21, 235] by formally assigning the elements 121-164 to (nlj) slots on the basis of the electron configurations of their ions. Simple estimates are made for likely maximum oxidation states, i, of these elements M in their MX(i) compounds, such as i = 6 for UF(6). Particularly high i are predicted for the 6f elements.

  16. Supporting Data for Fiscal Year 1994. Budget Estimate Submission

    DTIC Science & Technology

    1993-04-01

    0603401F 405 36 Space Systems Environmental Interactions Technology 0603410F 416 38 Conventional Weapons Technology 0603601F 423 39 Advanced Radiation...Transfer Pilot Program (SBIR/STTR) 0603302F Space and Missile Rocket Propulsion 31 392 060341OF Space Systems Environmental Interactions Technology 36...Deliver Interactive Decode (Rapid Message Processing) capability in Communications Element. - (U) Conduct maintainability demonstration. - (U) Begin Initial

  17. The discovery of plutonium reorganized the periodic table and aided the discovery of new elements

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

    Clark, David L

    2009-01-01

    The modern Periodic Table derives principally from the work of the great Russian scientist Dimitri Mendeleev, who in 1869 enunciated a 'periodic law' that the properties of the elements are a periodic function of their atomic weights, and arranged the 65 known elements in a 'periodic table'. Fundamentally, every column in the main body of the Periodic Table is a grouping of elements that display similar chemical and physical behavior. Similar properties are therefore exhibited by elements with widely different mass. Chemical periodicity is central to the study of chemistry, and no other generalization comes close to its ability tomore » systematize and rationalize known chemical facts. With the development of atomic theory, and an understanding of the electronic structure of atoms, chemical periodicity and the periodic table now find their natural explanation in the electronic structure of atoms. Moving from left to right along any row, the elements are arranged sequentially according to nuclear charge (the atomic number). Electrons counter balance that nuclear charge, hence each successive element has one more electron in its configuration. The electron configuration, or distribution of electrons among atomic orbitals, may be determined by application of the Pauli principle (paired spin in the same orbital) and the aufbau principle (which outlines the order of filling of electrons into shells of orbitals - s, p, d, f, etc.) such that in a given atom, no two electrons may have all four quantum numbers identical. In 1939, only three elements were known to be heavier than actinium: thorium, protactinium, and uranium. All three exhibited variable oxidation states and a complex chemistry. Thorium, protactinium and uranium were assumed to be d-transition metals and were placed in the Periodic Table under hafnium, tantalum, and tungsten, respectively. By 1940, McMillan and Abelson bombarded uranium atoms with slow neutrons and successfully identified atoms of element 93, which they named neptunium after the planet Neptune. This rapidly set the stage for the discovery of the next succeeding element, plutonium (Seaborg, McMillan, Kennedy, and Wahl, 1940), named after the next planet away from the Sun, Pluto. The newly discovered elements were presumed to fit comfortably in the Periodic Table under rhenium and osmium, respectively. However, subsequent tracer chemical experiments showed that neptunium and plutonium were closer in their chemical properties to uranium than their presumed homologues, rhenium and osmium. Spectroscopic evidence also indicated that the new elements were not typical transition elements, but had f-electrons in their valence shell. Thus, several researchers, including McMillan and Wahl, and Zachariasen at Los Alamos, suggested that these elements might be part of a second inner-transition series in which the 5f-electron subshell was being filled. It was not clear, however, where the new series would begin. McMillian had proposed a 'uraninide series' that started with neptunium, but attempts to isolate elements with atomic numbers 95 and 96 based on assumed similarities to uranium were unsuccessful. Both Wahl and Zacharias en had proposed a thoride series that started with protactinium. In 1944, Seaborg proposed that the series started with thorium, and that all of the elements heavier than actinium constituted an 'actinide' series similar to the lanthanides. Because the 5f-shell began filling in the same relative position as the 4f-shell, the electronic configuration of elements in the two series would be similar. Guided by the hypothesis that elements 95 and 96 were homologues of europium and gadolinium, new experiments were designed and the elements were uniquely synthesized and separated from all others. The new elements were subsequently named americium and curium. Seaborg's 'Actinide Concept' thus played a major role in the discovery of the transplutonium elements. It provided the framework that supported synthesis, isolation, and identification of the succeeding actinide elements berkelium through lawrencium and beyond to the element with Atomic Number 118. But as research has progressed in the study of the actinide elements, it has become clear that the 5f series has a unique chemistry that is distinct from the lanthanides. One of the focal points of study in actinide research has been to better define the scope and limitations of the actinide concept. Seaborg's actinide concept of heavy element electronic structure, prediction that the actinides form a transition series analogous to the rare earth series of lanthanide elements, is now well accepted in the scientific community and included in all standard configurations of the Periodic Table.« less

  18. Improving the quantity, quality and transparency of data used to derive radionuclide transfer parameters for animal products. 2. Cow milk.

    PubMed

    Howard, B J; Wells, C; Barnett, C L; Howard, D C

    2017-02-01

    Under the International Atomic Energy Agency (IAEA) MODARIA (Modelling and Data for Radiological Impact Assessments) Programme, there has been an initiative to improve the derivation, provenance and transparency of transfer parameter values for radionuclides from feed to animal products that are for human consumption. A description of the revised MODARIA 2016 cow milk dataset is described in this paper. As previously reported for the MODARIA goat milk dataset, quality control has led to the discounting of some references used in IAEA's Technical Report Series (TRS) report 472 (IAEA, 2010). The number of Concentration Ratio (CR) values has been considerably increased by (i) the inclusion of more literature from agricultural studies which particularly enhanced the stable isotope data of both CR and F m and (ii) by estimating dry matter intake from assumed liveweight. In TRS 472, the data for cow milk were 714 transfer coefficient (F m ) values and 254 CR values describing 31 elements and 26 elements respectively. In the MODARIA 2016 cow milk dataset, F m and CR values are now reported for 43 elements based upon 825 data values for F m and 824 for CR. The MODARIA 2016 cow milk dataset F m values are within an order of magnitude of those reported in TRS 472. Slightly bigger changes are seen in the CR values, but the increase in size of the dataset creates greater confidence in them. Data gaps that still remain are identified for elements with isotopes relevant to radiation protection. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Interleukin-1 homologues IL-1F7b and IL-18 contain functional mRNA instability elements within the coding region responsive to lipopolysaccharide

    PubMed Central

    2004-01-01

    IL-1F7b, a novel homologue of the IL-1 (interleukin 1) family, was discovered by computational cloning. We demonstrated that IL-1F7b shares critical amino acid residues with IL-18 and binds to the IL-18-binding protein enhancing its ability to inhibit IL-18-induced interferon-γ. We also showed that low levels of IL-1F7b are constitutively present intracellularly in human blood monocytes. In this study, we demonstrate that similar to IL-18, both mRNA and intracellular protein expression of IL-1F7b are up-regulated by LPS (lipopolysaccharide) in human monocytes. In stable transfectants of murine RAW264.7 macrophage cells, there was no IL-1F7b protein expression despite a highly active CMV promoter. We found that IL-1F7b-specific mRNA was rapidly degraded in transfected cells, via a 3′-UTR (untranslated region)-independent control of IL-1F7b transcript stability. After LPS stimulation, there was a rapid transient increase in IL-1F7b-specific mRNA and concomitant protein levels. Using sequence alignment, we found a conserved ten-nucleotide homology box within the open reading frame of IL-F7b, which is flanking the coding region instability elements of some selective genes. In-frame deletion of downstream exon 5 from the full-length IL-1F7b cDNA markedly increased the levels of IL-1F7b mRNA. A similar coding region element is located in IL-18. When transfected into RAW264.7 macrophages, IL-18 mRNA was also unstable unless treated with LPS. These results indicate that both IL-1F7b and IL-18 mRNA contain functional instability determinants within their coding region, which influence mRNA decay as a novel mechanism to regulate the expression of IL-1 family members. PMID:15046617

  20. Speciation of the trivalent f-elements Eu(III) and Cm(III) in digestive media.

    PubMed

    Wilke, Claudia; Barkleit, Astrid; Stumpf, Thorsten; Ikeda-Ohno, Atsushi

    2017-10-01

    In case radioactive materials are released into the environment, their incorporation into our digestive system would be a significant concern. Trivalent f-elements, i.e., trivalent actinides and lanthanides, could potentially represent a serious health risk due to their chemo- and radiotoxicity, nevertheless the biochemical behavior of these elements are mostly unknown even to date. This study, therefore, focuses on the chemical speciation of trivalent f-elements in the human gastrointestinal tract. To simulate the digestive system artificial digestive juices (saliva, gastric juice, pancreatic juice and bile fluid) were prepared. The chemical speciation of lanthanides (as Eu(III)) and actinides (as Cm(III)) was determined experimentally by time-resolved laser-induced fluorescence spectroscopy (TRLFS) and the results were compared with thermodynamic modeling. The results indicate a dominant inorganic species with phosphate/carbonate in the mouth, while the aquo ion is predominantly formed with a minor contribution of the enzyme pepsin in the stomach. In the intestinal tract the most significant species are with the protein mucin. We demonstrated the first experimental results on the chemical speciation of trivalent f-elements in the digestive media by TRLFS. The results highlight a significant gap in chemical speciation between experiments and thermodynamic modeling due to the limited availability of thermodynamic stability constants particularly for organic species. Chemical speciation strongly influences the in vivo behavior of metal ions. Therefore, the results of this speciation study will help to enhance the assessment of health risks and to improve decorporation strategies after ingestion of these (radio-)toxic heavy metal ions. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Database Design for Structural Analysis and Design Optimization.

    DTIC Science & Technology

    1984-10-01

    2) . Element number of nodes IELT NPAR(2) " Stress printing flag IPST NPAR(2) Element material angle BETA NPAR(2) Element thickness THICK NPAR(2...number LM 3*NPAR(17)*NPAR(2) Element nodal coordinates XYZ 3*NPAR(17)*NPAR(2) Element number of nodes IELT NPAR(2) Element geometry number of nodes IELTX...D.O.F. number LM 6*NPAR(7)*NPAR(2) Element number of nodes IELT NPAR(2) Material property set number MATP NPAR(2) Material constants PROP NPAR(17

  2. Physics-based Stabilization of Spectral Elements for the 3D Euler Equations of Moist Atmospheric Convection

    DTIC Science & Technology

    2014-06-01

    6000 s. 7 Table 1: Case 3. Comparative results of front location at 900s. LES (SEM), VMS (FE), WRF -ARW V2.2 (FD), f-wave (FV), filtered Spectral Elements...NO 14629 VMS [15] (75 m) NO 14487 VMS [15] (100 m) NO 14355 WRF -ARW 50 m YES 14470 SE [6] 50m YES 14767 DG [6] 50m YES 14767 f-wave (FV) [1] 50 m YES

  3. Fire and the Related Effects of Nuclear Explosions. 1982 Asilomar Conference,

    DTIC Science & Technology

    1982-11-01

    SRT International 333 Ravenswood Ave. Menlo Park, CA 94025 F2A Work Unit 2563F II. CONTROLLING OFFICE NAME AND AOoReSS US. REPORT OATS Federal...and Scope: 1. Define the events and modules to be used in the Urban Fire Demonstration Model along with appropriate data elements, control and data...1) a specific control structure to sequence and organize the various computational V- 9 elements of an interactive simulation, and (2) emphasis

  4. The First Row Anomaly and Recoupled Pair Bonding in the Halides of the Late p-Block Elements

    PubMed Central

    2012-01-01

    The dramatic differences between the properties of molecules formed from the late p-block elements of the first row of the periodic table (N–F) and those of the corresponding elements in subsequent rows is well recognized as the first row anomaly. Certain properties of the atoms, such as the relative energies and spatial extents of the ns and np orbitals, can explain some of these differences, but not others. In this Account, we summarize the results of our recent computational studies of the halides of the late p-block elements. Our studies point to a single underlying cause for many of these differences: the ability of the late p-block elements in the second and subsequent rows of the periodic table to form recoupled pair bonds and recoupled pair bond dyads with very electronegative ligands. Recoupled pair bonds form when an electron in a singly occupied ligand orbital recouples the pair of electrons in a doubly occupied lone pair orbital on the central atom, leading to a central atom-ligand bond. Recoupled pair bond dyads occur when a second ligand forms a bond with the orbital left over from the initial recoupled pair bond. Recoupled pair bonds and recoupled pair bond dyads enable the late p-block elements to form remarkably stable hypervalent compounds such as PF5 and SF6 and lead to unexpected excited states in smaller halides of the late p-block elements such as SF and SF2. Recoupled pair bonding also causes the Fn–1X–F bond energies to oscillate dramatically once the normal valences of the central atoms have been satisfied. In addition, recoupled pair bonding provides a lower-energy pathway for inversion in heavily fluorinated compounds (PF3 and PF2H, but not PH2F and PH3) and leads to unusual intermediates and products in reactions involving halogens and late p-block element compounds, such as (CH3)2S + F2. Although this Account focuses on the halides of the second row, late p-block elements, recoupled pair bonds and recoupled pair bond dyads are important in the chemistry of p-block elements beyond the second row (As, Se, and Br) and for compounds of these elements with other very electronegative ligands, such as OH and O. Knowledge of recoupled pair bonding is thus critical to understanding the properties and reactivity of molecules containing the late p-block elements beyond the first row. PMID:23151313

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

    Plint, Trevor; Lessard, Benoît H.; Bender, Timothy P.

    In this study, we have assessed the potential application of group 13 and 14 metal and metalloid phthalocyanines ((X){sub n}-MPcs) and their axially substituted derivatives as hole-transporting layers in organic light emitting diodes (OLEDs). OLEDs studied herein have the generic structure of glass/ITO/(N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) or (X){sub n}-MPc)(50 nm)/Alq{sub 3} (60 nm)/LiF (1 nm)/Al (80 nm), where X is an axial substituent group. OLEDs using chloro aluminum phthalocyanine (Cl-AlPc) showed good peak luminance values of 2620 ± 113 cd/m{sup 2} at 11 V. To our knowledge, Cl-AlPc has not previously been shown to work as a hole transport material (HTL) in OLEDs. Conversely, the di-chlorides of silicon, germanium, andmore » tin phthalocyanine (Cl{sub 2}-SiPc, Cl{sub 2}-GePc, and Cl{sub 2}-SnPc, respectively) showed poor performance compared to Cl-AlPc, having peak luminances of only 38 ± 4 cd/m{sup 2} (12 V), 23 ± 1 cd/m{sup 2} (8.5 V), and 59 ± 5 cd/m{sup 2} (13.5 V), respectively. However, by performing a simple axial substitution of the chloride groups of Cl{sub 2}-SiPc with pentafluorophenoxy groups, the resulting bis(pentafluorophenoxy) silicon phthalocyanine (F{sub 10}-SiPc) containing OLED had a peak luminance of 5141 ± 941 cd/m{sup 2} (10 V), a two order of magnitude increase over its chlorinated precursor. This material showed OLED characteristics approaching those of a baseline OLED based on the well-studied triarylamine NPB. Attempts to attach the pentafluorophenoxy axial group to both SnPc and GePc were hindered by synthetic difficulties and low thermal stability, respectively. In light of the performance improvements observed by simple axial substitution of SiPc in OLEDs, the use of axially substituted MPcs in organic electronic devices remains of continuing interest to us and potentially the field in general.« less

  6. Assessing the potential of group 13 and 14 metal/metalloid phthalocyanines as hole transport layers in organic light emitting diodes

    NASA Astrophysics Data System (ADS)

    Plint, Trevor; Lessard, Benoît H.; Bender, Timothy P.

    2016-04-01

    In this study, we have assessed the potential application of group 13 and 14 metal and metalloid phthalocyanines ((X)n-MPcs) and their axially substituted derivatives as hole-transporting layers in organic light emitting diodes (OLEDs). OLEDs studied herein have the generic structure of glass/ITO/(N,N'-di(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPB) or (X)n-MPc)(50 nm)/Alq3 (60 nm)/LiF (1 nm)/Al (80 nm), where X is an axial substituent group. OLEDs using chloro aluminum phthalocyanine (Cl-AlPc) showed good peak luminance values of 2620 ± 113 cd/m2 at 11 V. To our knowledge, Cl-AlPc has not previously been shown to work as a hole transport material (HTL) in OLEDs. Conversely, the di-chlorides of silicon, germanium, and tin phthalocyanine (Cl2-SiPc, Cl2-GePc, and Cl2-SnPc, respectively) showed poor performance compared to Cl-AlPc, having peak luminances of only 38 ± 4 cd/m2 (12 V), 23 ± 1 cd/m2 (8.5 V), and 59 ± 5 cd/m2 (13.5 V), respectively. However, by performing a simple axial substitution of the chloride groups of Cl2-SiPc with pentafluorophenoxy groups, the resulting bis(pentafluorophenoxy) silicon phthalocyanine (F10-SiPc) containing OLED had a peak luminance of 5141 ± 941 cd/m2 (10 V), a two order of magnitude increase over its chlorinated precursor. This material showed OLED characteristics approaching those of a baseline OLED based on the well-studied triarylamine NPB. Attempts to attach the pentafluorophenoxy axial group to both SnPc and GePc were hindered by synthetic difficulties and low thermal stability, respectively. In light of the performance improvements observed by simple axial substitution of SiPc in OLEDs, the use of axially substituted MPcs in organic electronic devices remains of continuing interest to us and potentially the field in general.

  7. Quantifying Trust, Distrust, and Suspicion in Human-System Interactions

    DTIC Science & Technology

    2015-10-26

    devices which require subjects to lie in restricted positions ( fMRI ), or to drink hazardous materials (PET), EEG and fNIRS can non-invasively measure... fMRI . Since fNIRS and fMRI both measure elements of the Blood Oxygen Level Dependent (BOLD) signal. Researchers have recently explored the...response inhibition load, verbal working memory load, and spatial working memory load [1, 7]. We have also successfully localized brain regions such as

  8. The F-box family genes as key elements in response to salt, heavy mental, and drought stresses in Medicago truncatula.

    PubMed

    Song, Jian Bo; Wang, Yan Xiang; Li, Hai Bo; Li, Bo Wen; Zhou, Zhao Sheng; Gao, Shuai; Yang, Zhi Min

    2015-07-01

    F-box protein is a subunit of Skp1-Rbx1-Cul1-F-box protein (SCF) complex with typically conserved F-box motifs of approximately 40 amino acids and is one of the largest protein families in eukaryotes. F-box proteins play critical roles in selective and specific protein degradation through the 26S proteasome. In this study, we bioinformatically identified 972 putative F-box proteins from Medicago truncatula genome. Our analysis showed that in addition to the conserved motif, the F-box proteins have several other functional domains in their C-terminal regions (e.g., LRRs, Kelch, FBA, and PP2), some of which were found to be M. truncatula species-specific. By phylogenetic analysis of the F-box motifs, these proteins can be classified into three major families, and each family can be further grouped into more subgroups. Analysis of the genomic distribution of F-box genes on M. truncatula chromosomes revealed that the evolutional expansion of F-box genes in M. truncatula was probably due to localized gene duplications. To investigate the possible response of the F-box genes to abiotic stresses, both publicly available and customer-prepared microarrays were analyzed. Most of the F-box protein genes can be responding to salt and heavy metal stresses. Real-time PCR analysis confirmed that some of the F-box protein genes containing heat, drought, salicylic acid, and abscisic acid responsive cis-elements were able to respond to the abiotic stresses.

  9. Useful ion yields for Cameca IMS 3f and 6f SIMS: Limits on quantitative analysis

    USGS Publications Warehouse

    Hervig, R.L.; Mazdab, F.K.; Williams, Pat; Guan, Y.; Huss, G.R.; Leshin, L.A.

    2006-01-01

    The useful yields (ions detected/atom sputtered) of major and trace elements in NIST 610 glass were measured by secondary ion mass spectrometry (SIMS) using Cameca IMS 3f and 6f instruments. Useful yields of positive ions at maximum transmission range from 10-4 to 0.2 and are negatively correlated with ionization potential. We quantified the decrease in useful yields when applying energy filtering or high mass resolution techniques to remove molecular interferences. The useful yields of selected negative ions (O, S, Au) in magnetite and pyrite were also determined. These data allow the analyst to determine if a particular analysis (trace element contents or isotopic ratio) can be achieved, given the amount of sample available and the conditions of the analysis. ?? 2005 Elsevier B.V. All rights reserved.

  10. Polyadenylation proteins CstF-64 and τCstF-64 exhibit differential binding affinities for RNA polymers

    PubMed Central

    Monarez, Roberto R.; Macdonald, Clinton C.; Dass, Brinda

    2006-01-01

    CstF-64 (cleavage stimulation factor-64), a major regulatory protein of polyadenylation, is absent during male meiosis. Therefore a paralogous variant, τCstF-64 is expressed in male germ cells to maintain normal spermatogenesis. Based on sequence differences between τCstF-64 and CstF-64, and on the high incidence of alternative polyadenylation in testes, we hypothesized that the RBDs (RNA-binding domains) of τCstF-64 and CstF-64 have different affinities for RNA elements. We quantified Kd values of CstF-64 and τCstF-64 RBDs for various ribopolymers using an RNA cross-linking assay. The two RBDs had similar affinities for poly(G)18, poly(A)18 or poly(C)18, with affinity for poly(C)18 being the lowest. However, CstF-64 had a higher affinity for poly(U)18 than τCstF-64, whereas it had a lower affinity for poly(GU)9. Changing Pro-41 to a serine residue in the CstF-64 RBD did not affect its affinity for poly(U)18, but changes in amino acids downstream of the C-terminal α-helical region decreased affinity towards poly(U)18. Thus we show that the two CstF-64 paralogues differ in their affinities for specific RNA sequences, and that the region C-terminal to the RBD is important in RNA sequence recognition. This supports the hypothesis that τCstF-64 promotes germ-cell-specific patterns of polyadenylation by binding to different downstream sequence elements. PMID:17029590

  11. Di­aqua­bis­[2-(2-hy­droxy­eth­yl)pyridine-κ2 N,O]cobalt(II) dichloride

    PubMed Central

    Zeghouan, Ouahida; Guenifa, Fatiha; Hadjadj, Nasreddine; Bendjeddou, Lamia; Merazig, Hocine

    2013-01-01

    In the title salt, [Co(C7H9NO)2(H2O)2]Cl2, the CoII cation, located on an inversion center, is N,O-chelated by two hy­droxy­ethyl­pyridine ligands and coordinated by two water mol­ecules in a distorted O4N2 octa­hedral geometry. In the crystal, the Cl− anions link with the complex cations via O—H⋯Cl hydrogen bonds, forming a three-dimensional supra­molecular architecture. π–π stacking is observed between the pyridine rings of adjacent mol­ecules [centroid–centroid distance = 3.5810 (11) Å]. PMID:24109269

  12. New water-soluble metal working fluids additives from phosphonic acid derivatives for aluminum alloy materials.

    PubMed

    Kohara, Ichitaro; Tomoda, Hideyuki; Watanabe, Shoji

    2007-01-01

    Water-soluble metal working fluids are used for processing of aluminum alloy materials. This short paper describes properties of new additives for water-soluble cutting fluids for aluminum alloy materials. Some alkyldiphosphonic acids were prepared with known method. Amine salts of these phosphonic acids showed anti-corrosion property for aluminum alloy materials. However, they have no hard water tolerance. Monoesters of octylphosphonic acid were prepared by the reaction of octylphosphonic acid dichloride with various alcohols in the presence of triethylamine. Amine salts of monoester of octylphosphonic acid with diethyleneglycol monomethyl ether, ethyleneglycol monomethyl ether and triethyleneglycol monomethyl ether showed both of a good anti-corrosion property for aluminum alloy materials and hard water tolerance.

  13. Chloridobis(ethyl­enediamine-κ2 N,N′)(n-pentyl­amine-κN)cobalt(III) dichloride monhydrate

    PubMed Central

    Anbalagan, K.; Tamilselvan, M.; Nirmala, S.; Sudha, L.

    2009-01-01

    The title complex, [CoCl(C5H13N)(C2H8N2)2]Cl2·H2O, comprises one chloridobis(ethyl­enediamine)(n-pentyl­amine)cobalt(III) cation, two chloride counter-anions and a water mol­ecule. The CoIII atom of the complex is hexa­coordinated by five N and one Cl atoms. The five N atoms are from two chelating ethyl­enediamine and one n-pentyl­amine ligands. Neighbouring cations and anions are connected by N—H⋯Cl and N—H⋯O hydrogen bonds to each other and also to the water mol­ecule. PMID:21582753

  14. Nano-Zirconium Tungstate Reinforced Liquid Crystalline Thermosetting Composites with Near Zero Thermal Expansion

    DTIC Science & Technology

    2015-06-25

    5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Washington State University, Pullman...1234. 5c. PROGRAM ELEMENT NUMBER. Enter all program element numbers as they appear in the report, e.g. 61101A. 5d. PROJECT NUMBER. Enter all... project numbers as they appear in the report, e.g. 1F665702D1257; ILIR. 5e. TASK NUMBER. Enter all task numbers as they appear in the report

  15. Pacific Ocean buoy temperature date

    EPA Pesticide Factsheets

    Pacific Ocean buoy temperature dataThis dataset is associated with the following publication:Carbone, F., M. Landis, C.N. Gencarelli, A. Naccarato, F. Sprovieri, F. De Simone, I.M. Hedgecock, and N. Pirrone. Sea surface temperature variation linked to elemental mercury concentrations measured on Mauna Loa. GEOPHYSICAL RESEARCH LETTERS. American Geophysical Union, Washington, DC, USA, online, (2016).

  16. Oxygen Fugacity at High Pressure: Equations of State of Metal-Oxide Pairs

    NASA Technical Reports Server (NTRS)

    Campbell A. J.; Danielson, L.; Righter, K.; Wang, Y.; Davidson, G.; Wang, Y.

    2006-01-01

    Oxygen fugacity (fO2) varies by orders of magnitude in nature, and can induce profound changes in the chemical state of a substance, and also in the chemical equilibrium of multicomponent systems. One prominent area in high pressure geochemistry, in which fO2 is widely recognized as a principal controlling factor, is that of metal-silicate partitioning of siderophile trace elements (e.g., [1]). Numerous experiments have shown that high pressures and temperatures can significantly affect metal/silicate partitioning of siderophile and moderately siderophile elements. Parameterization of these experimental results over P, T, X, and fO2 can allow the observed siderophile element composition of the mantle to be associated with particular thermodynamic conditions [2]. However, this is best done only if quantitative control exists over each thermodynamic variable relevant to the experiments. The fO2 values for many of these partitioning experiments were determined relative to a particular metal-oxide buffer (e.g., Fe-FeO (IW), Ni-NiO (NNO), Co-CoO, Re-ReO2 (RRO)), but the parameterization of all experimental results is weakened by the fact that the pressure-induced relative changes between these buffer systems are imprecisely known.

  17. Fluorine-ion conductivity of different technological forms of solid electrolytes R{sub 1–y}M{sub y}F{sub 3–y} (LaF{sub 3} Type ) (M = Ca, Sr, Ba; R Are Rare Earth Elements)

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

    Sorokin, N. I., E-mail: nsorokin1@yandex.ru; Sobolev, B. P.

    We have investigated the conductivity of some representatives of different technological forms of fluoride-conducting solid electrolytes R{sub 1–y}M{sub y}F{sub 3–y} (M = Ca, Sr, Ba; R are rare earth elements) with an LaF{sub 3} structure: single crystals, cold- and hot-pressing ceramics based on a charge prepared in different ways (mechanochemical synthesis, solid-phase synthesis, and fragmentation of single crystals), polycrystalline alloys, etc. It is shown (by impedance spectroscopy), that different technological forms of identical chemical composition (R, M, y) exhibit different electrical characteristics. The maximum conductivity is observed for the single-crystal form of R{sub 1–y}M{sub y}F{sub 3–y} tysonite phases, which providesmore » (in contrast to other technological forms) the formation of true volume ion-conducting characteristics.« less

  18. Final Technical Report

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

    Dr. Asok K. Ray

    2012-05-22

    During the past decades, considerable theoretical efforts have been devoted to studying the electronic and geometric structures and related properties of surfaces. Such efforts are particularly important for systems like the actinides for which experimental work is relatively difficult to perform due to material problems and toxicity. The actinides are characterized by a gradual filling of the 5f-electron shell with the degree of localization increasing with the atomic number Z along the last series of the periodic table. The open shell of the 5f electrons determines the atomic, molecular, and solid state properties of the actinide elements and their compoundsmore » and understanding the quantum mechanics of the 5f electrons is the defining issue in the chemistry and physics of actinide elements. These elements are also characterized by the increasing prominence of relativistic effects and their studies can, in fact, help us understand the role of relativity throughout the periodic table. However, the electronic and geometric structures of the actinides, specifically the trans-uranium actinides and the roles of the 5f electrons in chemical bonding are still not well understood. This is crucial not only for our understanding of the actinides but also for the fact that the actinides constitute 'the missing link' between the d transition elements and the lanthanides. The 5f orbitals have properties intermediate between those of localized 4f and delocalized 3d orbitals. Thus, a proper understanding of the actinides will help us understand the behavior of the lanthanides and transition metals as well. In fact, there is an urgent need for continued extensive and detailed theoretical research in this area to provide significant and deep understandings of the electronic and geometric structures of the actinides. In this work, we have performed electronic structure studies for plutonium (Pu), americium (Am), and curium (Cm) surfaces, and molecular adsorptions on Pu and Am surfaces. In particular, the region at the boundary of Pu and Am, is widely believed to be the crossover region between d-like itinerant and f-like localized behavior The eventual goal is a complete understanding of the surface chemistry and physics processes of all actinide surfaces, defining the chemistry and physics of such heavy elements. Among the actinides, plutonium, with five 5f electrons in the solid state, is arguably the most complex, fascinating, and enigmatic element known to mankind and has attracted extraordinary scientific and technological interests because of its unique properties, generating a significant body of research in diverse areas, including superconductivity. Pu has, at least, six stable allotropes between room temperature and melting at atmospheric pressure, indicating that the valence electrons can hybridize into a number of complex bonding arrangements. Central and critical questions relate to the electronic structure, localization of the 5f electrons and the magnetism of Pu. For the light-actinides, from Th to Pu, the 5f electrons are believed to be delocalized, hybridizing with the 6d and 7s electrons. For the heavier actinides, Am and beyond, the 5f electrons are localized with the 5f orbitals progressively lower in energy relative to the 6d configuration. Hence, Pu is in a position where the 5f electronic behavior changes from itinerant to localized. As far as magnetism is concerned, a majority of the theoretical calculations continues to claim the existence of magnetism while almost all the experimental results do not find any support for such claims. The second element of interest to us, namely americium, occupies a central position in the actinide series with respect to the involvement of 5f electrons in metallic bonding. It is widely believed that the 5f electrons in Am are localized and that Am undergoes a series of crystallographic phase changes with pressure. Fully-relativistic all electron surface studies of the different phases of Am, initially for the dhcp and the fcc surfaces, can and have provided us with valuable information about chemical bonding in Am and the transitions from f-electron delocalization to f-electron localization in trans-uranium compounds. In particular, a comparative study of the electronic structures of the Pu and Am surfaces using the techniques of all-electron modern density functional theory and beyond can provide significant information about the role of 5f electrons in bond formation as also the localization of the 5f electrons, matters of considerable controversies. The change from metallic 5f bonding into local-moment nonbonding configurations that takes place between Pu and Am is rather unique in the periodic table and is at the very heart of our understanding of electronic structure. We believe that, considering the narrow bandwidth of surface states, any transition from itinerant to localized behavior first takes place at the actinide surfaces with possible reconstructions.« less

  19. Profiling of new psychoactive substances (NPS) by using stable isotope ratio mass spectrometry (IRMS): study on the synthetic cannabinoid 5F-PB-22.

    PubMed

    Münster-Müller, S; Scheid, N; Holdermann, T; Schneiders, S; Pütz, M

    2018-05-21

    In this paper results of a pilot study on the profiling of the synthetic cannabinoid receptor agonist 5F-PB-22 (5F-QUPIC, pentylfluoro-1H-indole-3-carboxylic acid-8-quinolinyl ester) via isotope ratio mass spectrometry are presented. It is focused on δ 13 C, δ 15 N and δ 2 H isotope ratios, which are determined using elemental analyser (EA) and high temperature elemental analyser (TC/EA) coupled to an isotope ratio mass spectrometer (IRMS). By means of a sample of pure material of 5F-PB-22 it is shown that the extraction of 5F-PB-22 from herbal material, a rapid clean-up procedure, or preparative column chromatography had no influences on the isotope ratios. Furthermore, 5F-PB-22 was extracted from fourteen different herbal blend samples ("Spice products" from police seizures) and analysed via IRMS, yielding three clusters containing seven, five and two samples, distinguishable through their isotopic composition, respectively. It is assumed that herbal blends in each cluster have been manufactured from individual batches of 5F-PB-22. This article is protected by copyright. All rights reserved.

  20. Lifetime of a Chemically Bound Helium Compound

    NASA Technical Reports Server (NTRS)

    Chaban, Galina M.; Lundell, Jan; Gerber, R. Benny; Kwak, Dochan (Technical Monitor)

    2001-01-01

    The rare-gas atoms are chemically inert, to an extent unique among all elements. This is due to the stable electronic structure of the atoms. Stable molecules with chemically bound rare-gas atoms are, however, known. A first such compound, XePtF6, W2S prepared in 1962 and since then a range of molecules containing radon, xenon and krypton have been obtained. Most recently, a first stable chemically bound compound of argon was prepared, leaving neon and helium as the only elements for which stable chemically bound molecules are not yet known. Electronic structure calculations predict that a metastable species HHeF exists, but significance of the result depends on the unknown lifetime. Here we report quantum dynamics calculations of the lifetime of HHeF, using accurate interactions computed from electronic structure theory. HHeF is shown to disintegrate by tunneling through energy barriers into He + HF and H + He + F the first channel greatly dominating. The lifetime of HHeF is more than 120 picoseconds, that of DHeF is 14 nanoseconds. The relatively long lifetimes are encouraging for the preparation prospects of this first chemically bound helium compound.

  1. Population Control of Self-Replicating Systems: Option C

    NASA Technical Reports Server (NTRS)

    Mccord, R. L.

    1983-01-01

    From the conception and development of the theory of self-replicating automata by John von Neumann, others have expanded on his theories. In 1980, Georg von Tiesenhausen and Wesley A. Darbro developed a report which is a "first' in presenting the theories in a conceptualized engineering setting. In that report several options involving self-replicating systems are presented. One of the options allows each primary to generate n replicas, one in each sequential time frame after its own generation. Each replica is limited to a maximum of m ancestors. This study involves determining the state vector of the replicas in an efficient manner. The problem is cast in matrix notation, where F = fij is a non-diagonalizable matrix. Any element fij represents the number of elements of type j = (c,d) in time frame k+1 generated from type i = (a,b) in time frame k. It is then shown that the state vector is: bar F(k)=bar F (non-zero) X F sub K = bar F (non-zero) xmx J sub kx m sub-1 where J is a matrix in Jordan form having the same eigenvalues as F. M is a matrix composed of the eigenvectors and the generalized eigenvectors of F.

  2. Ginsenoside F2 reduces hair loss by controlling apoptosis through the sterol regulatory element-binding protein cleavage activating protein and transforming growth factor-β pathways in a dihydrotestosterone-induced mouse model.

    PubMed

    Shin, Heon-Sub; Park, Sang-Yong; Hwang, Eun-Son; Lee, Don-Gil; Mavlonov, Gafurjon Turdalievich; Yi, Tae-Hoo

    2014-01-01

    This study was conducted to test whether ginsenoside F2 can reduce hair loss by influencing sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP) and the transforming growth factor beta (TGF-β) pathway of apoptosis in dihydrotestosterone (DHT)-treated hair cells and in a DHT-induced hair loss model in mice. Results for ginsenoside F2 were compared with finasteride. DHT inhibits proliferation of hair cells and induces androgenetic alopecia and was shown to activate an apoptosis signal pathway both in vitro and in vivo. The cell-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the proliferation rates of DHT-treated human hair dermal papilla cells (HHDPCs) and HaCaTs increased by 48% in the ginsenoside F2-treated group and by 12% in the finasteride-treated group. Western blot analysis showed that ginsenoside F2 decreased expression of TGF-β2 related factors involved in hair loss. The present study suggested a hair loss related pathway by changing SCAP related apoptosis pathway, which has been known to control cholesterol metabolism. SCAP, sterol regulatory element-binding protein (SREBP) and caspase-12 expression in the ginsenoside F2-treated group were decreased compared to the DHT and finasteride-treated group. C57BL/6 mice were also prepared by injection with DHT and then treated with ginsenoside F2 or finasteride. Hair growth rate, density, thickness measurements and tissue histotological analysis in these groups suggested that ginsenoside F2 suppressed hair cell apoptosis and premature entry to catagen more effectively than finasteride. Our results indicated that ginsenoside F2 decreased the expression of TGF-β2 and SCAP proteins, which have been suggested to be involved in apoptosis and entry into catagen. This study provides evidence those factors in the SCAP pathway could be targets for hair loss prevention drugs.

  3. Detection of tetQ and ermF antibiotic resistance genes in Prevotella and Porphyromonas isolates from clinical specimens and resident microbiota of humans.

    PubMed

    Arzese, A R; Tomasetig, L; Botta, G A

    2000-05-01

    Gram-negative anaerobes belonging to the genera Fusobacterium, Prevotella and Porphyromonas were investigated for the presence of tetQ and ermF, which have been shown to be spread by conjugal elements. One hundred isolates from either sites of infection or various body sites in healthy subjects were studied. PCR was used to detect tetQ, and DNA-DNA hybridization studies on EcoRI chromosomal digests were undertaken to detect the presence of tetQ and ermF. Antibiotic sensitivity assays were performed on selected isolates to detect tetracycline, erythromycin and penicillin resistance. Twenty Fusobacterium isolates lacked tetQ, and were tetracycline sensitive. Twenty per cent of Prevotella spp. isolates both from clinical specimens and from healthy subjects were found to possess tetQ. Of 20 Porphyromonas isolates tested, one (Porphyromonas levii) from a case of bacterial vaginosis was shown to possess tetQ in the chromosome. The presence of tetQ was always associated with tetracycline resistance. Four isolates of Prevotella melaninogenica and one isolate of Prevotella were ermF-positive, although expression of erythromycin resistance was not consistently associated with detection of this gene. Antibiotic resistance phenotypes of Prevotella isolates were shown to be related to specific chromosomal restriction patterns by hybridization studies: tetracycline resistance and tetracycline/erythromycin resistance are conferred by Bacteroides tetracycline-resistant ERL elements, whereas the tetracycline/penicillin resistance phenotype could be due to spread of elements identified in Prevotella only. Tetracycline/erythromycin-resistant and tetracycline/erythromycin/penicillin-resistant P. melaninogenica isolates were found in this study. It appeared that the presence of tetQ and ermF in Bacteroides and Prevotella contributed to the persistence of antibiotic resistance isolates within the host and to potential spread to other organisms through conjugal elements.

  4. Direct trans-activation of the human cyclin D2 gene by the oncogene product Tax of human T-cell leukemia virus type I.

    PubMed

    Huang, Y; Ohtani, K; Iwanaga, R; Matsumura, Y; Nakamura, M

    2001-03-01

    Cyclins are one of the pivotal determinants regulating cell cycle progression. We previously reported that the trans-activator Tax of human T-cell leukemia virus type I (HTLV-I) induces endogenous cyclin D2 expression along with cell cycle progression in a resting human T-cell line, Kit 225, suggesting a role of cyclin D2 in Tax-mediated cell cycle progression. The cyclin D2 gene has a typical E2F binding element, raising the possibility that induction of cyclin D2 expression is a consequence of cell cycle progression. In this study, we examined the role and molecular mechanism of induction of the endogenous human cyclin D2 gene by Tax. Introduction of p19(INK4d), a cyclin dependent kinase (CDK) inhibitor of the INK4 family specific for D-type CDK, inhibited Tax-mediated activation of E2F, indicating requirement of D-type CDK in Tax-mediated activation of E2F. Previously indicated E2F binding element and two NF-kappaB-like binding elements in the 1.6 kbp cyclin D2 promoter fragment had little, if any, effect on responsiveness to Tax. We found that trans-activation of the cyclin D2 promoter by Tax was mainly mediated by a newly identified NF-kappaB-like element with auxiliary contribution of a CRE-like element residing in sequences downstream of -444 which were by themselves sufficient for trans-activation by Tax. These results indicate that Tax directly trans-activates the cyclin D2 gene, resulting in growth promotion and perhaps leukemogenesis through activation of D-type CDK.

  5. Unrelated sequences at the 5' end of mouse LINE-1 repeated elements define two distinct subfamilies.

    PubMed Central

    Wincker, P; Jubier-Maurin, V; Roizès, G

    1987-01-01

    Some full length members of the mouse long interspersed repeated DNA family L1Md have been shown to be associated at their 5' end with a variable number of tandem repetitions, the A repeats, that have been suggested to be transcription controlling elements. We report that the other type of repeat, named F, found at the 5' end of a few L1 elements is also an integral part of full length L1 copies. Sequencing shows that the F repeats are GC rich, and organized in tandem. The L1 copies associated with either A or F repeats can be correlated with two different subsets of L1 sequences distinguished by a series of variant nucleotides specific to each and by unassociated but frequent restriction sites. These findings suggest that sequence replacement has occurred at least once in 5' of L1Md, and is related to the generation of specific subfamilies. Images PMID:3684566

  6. Aerosol Direct Fluorination. Syntheses of the Perfluoroalkyl Orthocarbonates, F-Tetramethyl and F-Ethylene Orthocarbonates.

    DTIC Science & Technology

    1984-03-30

    ff AD-AFRU9 98? AEROSOL DIRECT FLUORINATION SYNTHESES OF THE / 1 PERFLUOROALKYL ORTHOCRBONAT.-(U) TENNESSEE UNIY KNOXVILLE DEPT OF CHEMISTRY J L...SYNTHESES OF THE PERFLUOROALKYL ORTHOCARBONATES, F-TETRAMETHYL AND F-ETHYLENE ORTHOCARBONATES by James L. Adcock* and Mark L. Robin Department of...number) Aerosol, Direct Fluorination, Elemental Fluorine, Perfluoroalkyl % orthocarbonates 211,A’!S RACY (Contiue en reverse aide it neessary and

  7. Method of orbit sums in the theory of modular vector invariants

    NASA Astrophysics Data System (ADS)

    Stepanov, S. A.

    2006-12-01

    Let F be a field, V a finite-dimensional F-vector space, G\\leqslant \\operatorname{GL}_F(V) a finite group, and V^m=V\\oplus\\dots\\oplus V the m-fold direct sum with the diagonal action of G. The group G acts naturally on the symmetric graded algebra A_m=F \\lbrack V^m \\rbrack as a group of non-degenerate linear transformations of the variables. Let A_m^G be the subalgebra of invariants of the polynomial algebra A_m with respect to G. A classical result of Noether [1] says that if \\operatorname{char}F=0, then A_m^G is generated as an F-algebra by homogeneous polynomials of degree at most \\vert G\\vert, no matter how large m can be. On the other hand, it was proved by Richman [2], [3] that this result does not hold when the characteristic of F is positive and divides the order \\vert G\\vert of G. Let p, p>2, be a prime number, F=F_p a finite field of p elements, V a linear F_p-vector space of dimension n, and H\\leqslant \\operatorname{GL}_{F_p}(V) a cyclic group of order p generated by a matrix \\gamma of a certain special form. In this paper we describe explicitly (Theorem 1) one complete set of generators of A_m^H. After that, for an arbitrary complete set of generators of this algebra we find a lower bound for the highest degree of the generating elements of this algebra. This is a significant extension of the corresponding result of Campbell and Hughes [4] for the particular case of n=2. As a consequence we show (Theorem 3) that if m>n and G\\ge H is an arbitrary finite group, then each complete set of generators of A_m^G contains an element of degree at least 2(m-n+2r)(p-1)/r, where r=r(H) is a positive integer dependent on the structure of the generating matrix \\gamma of the group H. This result refines considerably the earlier lower bound obtained by Richman [3].

  8. 35. DETAILS AND SECTIONS OF FUEL ELEMENT SUPPORT PLATFORM, FUEL ...

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

    35. DETAILS AND SECTIONS OF FUEL ELEMENT SUPPORT PLATFORM, FUEL ELEMENT HOLDER, TRIP MECHANISM COVER, AND OTHER DETAILS. F.C. TORKELSON DRAWING NUMBER 842-ARVFS-701-S-3. INEL INDEX CODE NUMBER: 075 0701 60 851 151977. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  9. Ultrasound transducer positioning aid for fetal heart rate monitoring.

    PubMed

    Hamelmann, Paul; Kolen, Alex; Schmitt, Lars; Vullings, Rik; van Assen, Hans; Mischi, Massimo; Demi, Libertario; van Laar, Judith; Bergmans, Jan

    2016-08-01

    Fetal heart rate (fHR) monitoring is usually performed by Doppler ultrasound (US) techniques. For reliable fHR measurements it is required that the fetal heart is located within the US beam. In clinical practice, clinicians palpate the maternal abdomen to identify the fetal presentation and then the US transducer is fixated on the maternal abdomen where the best fHR signal can be obtained. Finding the optimal transducer position is done by listening to the strength of the Doppler audio output and relying on a signal quality indicator of the cardiotocographic (CTG) measurement system. Due to displacement of the US transducer or displacement of the fetal heart out of the US beam, the fHR signal may be lost. Therefore, it is often necessary that the obstetrician repeats the tedious procedure of US transducer positioning to avoid long periods of fHR signal loss. An intuitive US transducer positioning aid would be highly desirable to increase the work flow for the clinical staff. In this paper, the possibility to determine the fetal heart location with respect to the transducer by exploiting the received signal power in the transducer elements is shown. A commercially available US transducer used for fHR monitoring is connected to an US open platform, which allows individual driving of the elements and raw US data acquisition. Based on the power of the received Doppler signals in the transducer elements, the fetal heart location can be estimated. A beating fetal heart setup was designed and realized for validation. The experimental results show the feasibility of estimating the fetal heart location with the proposed method. This can be used to support clinicians in finding the optimal transducer position for fHR monitoring more easily.

  10. Stereochemical analysis of the functional significance of the conserved inverted CCAAT and TATA elements in the rat bone sialoprotein gene promoter.

    PubMed

    Su, Ming; Lee, Daniel; Ganss, Bernhard; Sodek, Jaro

    2006-04-14

    Basal transcription of the bone sialoprotein gene is mediated by highly conserved inverted CCAAT (ICE; ATTGG) and TATA elements (TTTATA) separated by precisely 21 nucleotides. Here we studied the importance of the relative position and orientation of the CCAAT and TATA elements in the proximal promoter by measuring the transcriptional activity of a series of mutated reporter constructs in transient transfection assays. Whereas inverting the TTTATA (wild type) to a TATAAA (consensus TATA) sequence increased transcription slightly, transcription was reduced when the flanking dinucleotides were also inverted. In contrast, reversing the ATTGG (wild type; ICE) to a CCAAT (RICE) sequence caused a marked reduction in transcription, whereas both transcription and NF-Y binding were progressively increased with the simultaneous inversion of flanking nucleotides (f-RICE-f). Reducing the distance between the ICE and TATA elements produced cyclical changes in transcriptional activity that correlated with progressive alterations in the relative positions of the CCAAT and TATA elements on the face of the DNA helix. Minimal transcription was observed after 5 nucleotides were deleted (equivalent to approximately one half turn of the helix), whereas transcription was fully restored after deleting 10 nucleotides (approximately one full turn of the DNA helix), transcriptional activity being progressively lost with deletions beyond 10 nucleotides. In comparison, when deletions were made with the ICE in the reversed (f-RICE-f) orientation transcriptional activity was progressively lost with no recovery. These results show that, although transcription can still occur when the CCAAT box is reversed and/or displaced relative to the TATA box, the activity is dependent upon the flexibility of the intervening DNA helix needed to align the NF-Y complex on the CCAAT box with preinitiation complex proteins that bind to the TATA box. Thus, the precise location and orientation of the CCAAT element is necessary for optimizing basal transcription of the bone sialoprotein gene.

  11. HD 54272, a classical λ Bootis star and γ Doradus pulsator

    NASA Astrophysics Data System (ADS)

    Paunzen, E.; Skarka, M.; Holdsworth, D. L.; Smalley, B.; West, R. G.

    2014-05-01

    We detect the second known λ Bootis star (HD 54272) which exhibits γ Doradus-type pulsations. The star was formerly misidentified as a RR Lyrae variable. The λ Bootis stars are a small group (only 2 per cent) of late B to early F-type, Population I stars which show moderate to extreme (up to a factor 100) surface underabundances of most Fe-peak elements and solar abundances of lighter elements (C, N, O, and S). The photometric data from the Wide Angle Search for Planets (WASP) and All Sky Automated Survey (ASAS) projects were analysed. They have an overlapping time base of 1566 d and 2545 d, respectively. Six statistically significant peaks were identified (f1 = 1.410 116 d-1, f2 = 1.283 986 d-1, f3 = 1.293 210 d-1, f4 = 1.536 662 d-1, f5 = 1.157 22 d-1 and f6 = 0.226 57 d-1). The spacing between f1 and f2, f1 and f4, f5 and f2 is almost identical. Since the daily aliasing is very strong, the interpretation of frequency spectra is somewhat ambiguous. From spectroscopic data, we deduce a high rotational velocity (250 ± 25 km s-1) and a metal deficiency of about -0.8 to -1.1 dex compared to the Sun. A comparison with the similar star, HR 8799, results in analogous pulsational characteristics but widely different astrophysical parameters. Since both are λ Bootis-type stars, the main mechanism of this phenomenon, selective accretion, may severely influence γ Doradus-type pulsations.

  12. Association of zygotic piRNAs derived from paternal P elements with hybrid dysgenesis in Drosophila melanogaster.

    PubMed

    Wakisaka, Keiko Tsuji; Ichiyanagi, Kenji; Ohno, Seiko; Itoh, Masanobu

    2018-01-01

    P -element transposition in the genome causes P-M hybrid dysgenesis in Drosophila melanogaster . Maternally deposited piRNAs suppress P -element transposition in the progeny, linking them to P-M phenotypes; however, the role of zygotic piRNAs derived from paternal P elements is poorly understood. To elucidate the molecular basis of P -element suppression by zygotic factors, we investigated the genomic constitution and P -element piRNA production derived from fathers. As a result, we characterized males of naturally derived Q, M' and P strains, which show different capacities for the P -element mobilizations introduced after hybridizations with M-strain females. The amounts of piRNAs produced in ovaries of F1 hybrids varied among the strains and were influenced by the characteristics of the piRNA clusters that harbored the P elements. Importantly, while both the Q- and M'-strain fathers restrict the P -element mobilization in ovaries of their daughters, the Q-strain fathers supported the production of the highest piRNA expression in the ovaries of their daughters, and the M' strain carries KP elements in transcriptionally active regions directing the highest expression of KP elements in their daughters. Interestingly, the zygotic P -element piRNAs, but not the KP element mRNA, contributed to the variations in P transposition immunity in the granddaughters. The piRNA-cluster-embedded P elements and the transcriptionally active KP elements from the paternal genome are both important suppressors of P element activities that are co-inherited by the progeny. Expression levels of the P -element piRNA and KP -element mRNA vary among F1 progeny due to the constitution of the paternal genome, and are involved in phenotypic variation in the subsequent generation.

  13. Functional cooperativity between two TPA responsive elements in undifferentiated F9 embryonic stem cells.

    PubMed Central

    Okuda, A; Imagawa, M; Sakai, M; Muramatsu, M

    1990-01-01

    We have recently identified an enhancer, termed GPEI, in the 5'-flanking region of the rat glutathione transferase P gene, that is composed of two imperfect TPA (phorbol 12-O-tetradecanoate 13-acetate) responsive elements (TREs). Unlike other TRE-containing enhancers, GPEI exhibits a strong transcriptional enhancing activity in F9 embryonic stem cells. Mutational analyses have revealed that the high activity of GPEI is mediated by two imperfect TREs. Each TRE-like sequence has no activity by itself but acts synergistically to form a strong enhancer which is active even in the very low level of AP-1 activity in F9 cells. Furthermore, we show that synthetic DNAs containing two perfect TREs in certain arrangements have strong transcriptional enhancing activities in F9 cells and the activity is greatly influenced by the relative orientation and the distance of two TREs. Images Fig. 1. Fig. 2. Fig. 3. PMID:2323334

  14. Direct and inverse theorems on approximation by root functions of a regular boundary-value problem

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

    Radzievskii, G V

    2006-08-31

    One considers the spectral problem x{sup (n)}+ Fx={lambda}x with boundary conditions U{sub j}(x)=0, j=1,...,n, for functions x on [0,1]. It is assumed that F is a linear bounded operator from the Hoelder space C{sup {gamma}}, {gamma} element of [0,n-1), into L{sub 1} and the U{sub j} are bounded linear functionals on C{sup k{sub j}} with k{sub j} element of {l_brace}0,...,n- 1{r_brace}. Let P{sub {zeta}} be the linear span of the root functions of the problem x{sup (n)}+ Fx={lambda}x, U{sub j}(x)=0, j=1,...,n, corresponding to the eigenvalues {lambda}{sub k} with |{lambda}{sub k}|<{zeta}{sup n}, and let E{sub {zeta}}(f){sub W{sub p}{sup l}}:=inf{l_brace}||f-g||{sub W{sub p}{supmore » l}}:g element of P{sub {zeta}}{r_brace}. An estimate of E{sub {zeta}}(f){sub W{sub p}{sup l}} is obtained in terms of the K-functional K({zeta}{sup -m},f;W{sub p}{sup l},W{sub p,U}{sup l+m}):= inf{l_brace}||f-x||{sub W{sub p}{sup l}}+{zeta}{sup -m}||x||{sub W{sub p}{sup l}{sup +}{sup m}}:x element of W{sub p}{sup l+m}, U{sub j}(x)=0 for k{sub j}

  15. Performance of Harshaw TLD-100H two-element Dosemeter.

    PubMed

    Luo, L Z; Rotunda, J E

    2006-01-01

    One of the advantages of LiF based thermoluminescent (TL) materials is its tissue-equivalent property. The Harshaw TLD-100H (LiF:Mg,Cu,P) material has demonstrated that it has a near-flat photon energy response and high sensitivity. With the optimized dosemeter filters built into the holder, the Harshaw TLD-100H two-element dosemeter can be used as a whole body personnel dosemeter for gamma, X ray and beta monitoring without the use of an algorithm or correction factor. This paper presents the dose performance of the Harshaw TLD-100H two-element dosemeter against the ANSI N13.11-2001 standard and the results of tests that are required in IEC 1066 International Standard.

  16. Labile rhizosphere soil solution fraction for prediction of bioavailability of heavy metals and rare earth elements to plants.

    PubMed

    Shan, Xiao-Quan; Wang, Zhongwen; Wang, Weisheng; Zhang, Shuzhen; Wen, Bei

    2003-02-01

    A labile rhizosphere soil solution fraction has been recommended to predict the bioavailability of heavy metals and rare earth elements to plants. This method used moist rhizosphere soil in combination with a mixture of 0.01 mol L(-1) of low-molecular-weight organic acids (LMWOAs) as extractant. The extracted soil solutions were fractionated into two colloidal fractions of <0.45 microm (F(3)) and <0.2 microm (F(2)), and one truly dissolved fraction including free metal ions and inorganic and organic complexes (fractionr(0.2 microm, LMWOAs) approximately r(0.45 microm, LMWOAs). In the case of rare earth elements the good correlation was obtained for both the wheat roots and shoots. Generally, the correlation coefficients obtained by LMWAOs were better than that obtained by the first step of BCR method. Therefore, LMWAOs and F(lrss) were strongly recommended to predict the bioavailability of metals in soil pools to plants.

  17. Catalytic Dehydrogenation of Dimethylamine Borane by Highly Active Thorium and Uranium Metallocene Complexes

    DOE PAGES

    Erickson, Karla A.; Kiplinger, Jaqueline L.

    2017-05-19

    In the thorium and uranium complexes (C 5Me 5) 2AnMe 2, [(C 5Me 5) 2An(H)(μ-H)] 2 (An = Th, U) and [(C 5Me 5) 2U(H)] 2 dehydrogenate dimethylamine borane (Me2NH·BH3) at room temperature. Upon mild heating at 45 °C, turnover frequencies (TOFs) of 400 h –1 are obtained, which is comparable to some of the fastest Me 2NH·BH 3 dehydrogenation catalysts known in the literature. We propose a β-hydride elimination mechanism for dehydrogenation because of the observation of Me 2N=BH 2, Me 2N=BMe 2, and Me 2N=BHMe in the 11B NMR spectra of catalytic and stoichiometric reactions. The similar catalyticmore » metrics between the actinide dimethyl and hydride complexes with Me 2NH·BH 3 indicate that the actinide hydride complexes are the active catalysts in this chemistry.« less

  18. Catalytic Dehydrogenation of Dimethylamine Borane by Highly Active Thorium and Uranium Metallocene Complexes

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

    Erickson, Karla A.; Kiplinger, Jaqueline L.

    In the thorium and uranium complexes (C 5Me 5) 2AnMe 2, [(C 5Me 5) 2An(H)(μ-H)] 2 (An = Th, U) and [(C 5Me 5) 2U(H)] 2 dehydrogenate dimethylamine borane (Me2NH·BH3) at room temperature. Upon mild heating at 45 °C, turnover frequencies (TOFs) of 400 h –1 are obtained, which is comparable to some of the fastest Me 2NH·BH 3 dehydrogenation catalysts known in the literature. We propose a β-hydride elimination mechanism for dehydrogenation because of the observation of Me 2N=BH 2, Me 2N=BMe 2, and Me 2N=BHMe in the 11B NMR spectra of catalytic and stoichiometric reactions. The similar catalyticmore » metrics between the actinide dimethyl and hydride complexes with Me 2NH·BH 3 indicate that the actinide hydride complexes are the active catalysts in this chemistry.« less

  19. Plasticized chitosan/polyolefin films produced by extrusion.

    PubMed

    Matet, Marie; Heuzey, Marie-Claude; Ajji, Abdellah; Sarazin, Pierre

    2015-03-06

    Plasticized chitosan and polyethylene blends were produced through a single-pass extrusion process. Using a twin-screw extruder, chitosan plasticization was achieved in the presence of an acetic acid solution and glycerol, and directly mixed with metallocene polyethylene, mPE, to produce a masterbatch. Different dilutions of the masterbatch (2, 5 and 10 wt% of plasticized chitosan), in the presence of ethylene vinyl acetate, EVA, were subsequently achieved in single screw film extrusion. Very small plasticized chitosan domains (number average diameter <5 μm) were visible in the polymeric matrix. The resulting films presented a brown color and increasing haze with chitosan plasticized content. Mechanical properties of the mPE films were affected by the presence of plasticized chitosan, but improvement was observed as a result of some compatibility between mPE and chitosan in the presence of EVA. Finally the incorporation of plasticized chitosan affected mPE water vapor permeability while oxygen permeability remained constant. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C 5Me 4R) 2UBr 2, (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br), and [K(THF)][(C 5Me 4R) 2UBr 2] (R = Me, Et)

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

    Lichtscheidl, Alejandro Gaston; Pagano, Justin K.; Scott, Brian Lindley

    The organometallic uranium species (C 5Me 4R) 2UBr 2 (R = Me, Et) were obtained by treating their chloride analogues (C 5Me 4R) 2UCl 2 (R = Me, Et) with Me 3SiBr. Treatment of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with K(O-2,6- iPr 2C 6H 3) afforded the halide aryloxide mixed-ligand complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(X) (R = Me, Et; X = Cl, Br). Complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br) (R = Me, Et) can also be synthesized by treating (C 5Me 4R) 2U(O-2,6-more » iPr 2C 6H 3)(Cl) (R = Me, Et) with Me 3SiBr, respectively. Reduction of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with KC 8 led to isolation of uranium(III) “ate” species [K(THF)][(C 5Me 5) 2UX 2] (X = Cl, Br) and [K(THF) 0.5][(C 5Me 4Et) 2UX 2] (X = Cl, Br), which can be converted to the neutral complexes (C 5Me 4R) 2U[N(SiMe 3) 2] (R = Me, Et). Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.« less

  1. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C 5Me 4R) 2UBr 2, (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br), and [K(THF)][(C 5Me 4R) 2UBr 2] (R = Me, Et)

    DOE PAGES

    Lichtscheidl, Alejandro Gaston; Pagano, Justin K.; Scott, Brian Lindley; ...

    2016-01-06

    The organometallic uranium species (C 5Me 4R) 2UBr 2 (R = Me, Et) were obtained by treating their chloride analogues (C 5Me 4R) 2UCl 2 (R = Me, Et) with Me 3SiBr. Treatment of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with K(O-2,6- iPr 2C 6H 3) afforded the halide aryloxide mixed-ligand complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(X) (R = Me, Et; X = Cl, Br). Complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br) (R = Me, Et) can also be synthesized by treating (C 5Me 4R) 2U(O-2,6-more » iPr 2C 6H 3)(Cl) (R = Me, Et) with Me 3SiBr, respectively. Reduction of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with KC 8 led to isolation of uranium(III) “ate” species [K(THF)][(C 5Me 5) 2UX 2] (X = Cl, Br) and [K(THF) 0.5][(C 5Me 4Et) 2UX 2] (X = Cl, Br), which can be converted to the neutral complexes (C 5Me 4R) 2U[N(SiMe 3) 2] (R = Me, Et). Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.« less

  2. 10 CFR 217.32 - Elements of a rated order.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Elements of a rated order. 217.32 Section 217.32 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Placement of Rated Orders § 217.32 Elements of a rated order. Each rated order must include: (a) The appropriate priority rating (e.g. DO-F1 or...

  3. 10 CFR 217.32 - Elements of a rated order.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Elements of a rated order. 217.32 Section 217.32 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Placement of Rated Orders § 217.32 Elements of a rated order. Each rated order must include: (a) The appropriate priority rating (e.g. DO-F1 or...

  4. 10 CFR 217.32 - Elements of a rated order.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Elements of a rated order. 217.32 Section 217.32 Energy DEPARTMENT OF ENERGY OIL ENERGY PRIORITIES AND ALLOCATIONS SYSTEM Placement of Rated Orders § 217.32 Elements of a rated order. Each rated order must include: (a) The appropriate priority rating (e.g. DO-F1 or...

  5. Wave Scattering in Heterogeneous Media using the Finite Element Method

    DTIC Science & Technology

    2016-10-21

    AFRL-AFOSR-JP-TR-2016-0086 Wave Scattering in Heterogeneous Media using the Finite Element Method Chiruvai Vendhan INDIAN INSTITUTE OF TECHNOLOGY...Scattering in Heterogeneous Media using the Finite Element Method 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA2386-12-1-4026 5c.  PROGRAM ELEMENT NUMBER 61102F 6...14.  ABSTRACT The primary aim of this study is to develop a finite element model for elastic scattering by axisymmetric bodies submerged in a

  6. Transgenerational effects of adolescent nicotine exposure in rats: Evidence for cognitive deficits in adult female offspring.

    PubMed

    Renaud, Samantha M; Fountain, Stephen B

    2016-01-01

    This study investigated whether adolescent nicotine exposure in one generation of rats would impair the cognitive capacity of a subsequent generation. Male and female rats in the parental F0 generation were given twice-daily i.p. injections of either 1.0mg/kg nicotine or an equivalent volume of saline for 35days during adolescence on postnatal days 25-59 (P25-59). After reaching adulthood, male and female nicotine-exposed rats were paired for breeding as were male and female saline control rats. Only female offspring were used in this experiment. Half of the offspring of F0 nicotine-exposed breeders and half of the offspring of F0 saline control rats received twice-daily i.p. injections of 1.0mg/kg nicotine during adolescence on P25-59. The remainder of the rats received twice-daily saline injections for the same period. To evaluate transgenerational effects of nicotine exposure on complex cognitive learning abilities, F1 generation rats were trained to perform a highly structured serial pattern in a serial multiple choice (SMC) task. Beginning on P95, rats in the F1 generation were given either 4days of massed training (20patterns/day) followed by spaced training (10 patterns/day) or only spaced training. Transgenerational effects of adolescent nicotine exposure were observed as greater difficulty in learning a "violation element" of the pattern, which indicated that rats were impaired in the ability to encode and remember multiple sequential elements as compound or configural cues. The results indicated that for rats that received massed training, F1 generation rats with adolescent nicotine exposure whose F0 generation parents also experienced adolescent nicotine exposure showed poorer learning of the violation element than rats that experienced adolescent nicotine exposure only in the F1 generation. Thus, adolescent nicotine exposure in one generation of rats produced a cognitive impairment in the next generation. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Computer Resources Handbook for Flight Critical Systems.

    DTIC Science & Technology

    1985-01-01

    8183 UNCLASSIFIED F /G 1 /3 NLllEEEEEEEEEEEE Illll lflflflflfl Illlfll..lflll EIEEIhEEIIIIII llElfllfllflfllfll .flflflflflflflflflflflll llEEEEEEllEII...Requiring Simulation .... ............. ... 114 6-4 Typical Transition Elements of Care III. ...... ............ 116 D- 1 F -16 Digital Flight Control...following forms: 1 . By reference to MIL- F -9490(for flight control systems); 2. By reference, with tailoring if required, to a Federal Aviation Regulation

  8. 75 FR 81349 - Change to the Reporting Date for Certain Data Elements Required Under the Mandatory Reporting of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... steel mills, steel companies, sinter plants, blast furnaces, basic oxygen process furnace shops. Lead... data or data that are less expensive to collect such as process data or material consumption data. For...)(1) Only annual anode consumption (No CEMS). F 98.66(f)(1) Only annual paste consumption (No CEMS). F...

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

    Hill, J. Grant, E-mail: grant.hill@sheffield.ac.uk, E-mail: kipeters@wsu.edu; Peterson, Kirk A., E-mail: grant.hill@sheffield.ac.uk, E-mail: kipeters@wsu.edu

    New correlation consistent basis sets, cc-pVnZ-PP-F12 (n = D, T, Q), for all the post-d main group elements Ga–Rn have been optimized for use in explicitly correlated F12 calculations. The new sets, which include not only orbital basis sets but also the matching auxiliary sets required for density fitting both conventional and F12 integrals, are designed for correlation of valence sp, as well as the outer-core d electrons. The basis sets are constructed for use with the previously published small-core relativistic pseudopotentials of the Stuttgart-Cologne variety. Benchmark explicitly correlated coupled-cluster singles and doubles with perturbative triples [CCSD(T)-F12b] calculations of themore » spectroscopic properties of numerous diatomic molecules involving 4p, 5p, and 6p elements have been carried out and compared to the analogous conventional CCSD(T) results. In general the F12 results obtained with a n-zeta F12 basis set were comparable to conventional aug-cc-pVxZ-PP or aug-cc-pwCVxZ-PP basis set calculations obtained with x = n + 1 or even x = n + 2. The new sets used in CCSD(T)-F12b calculations are particularly efficient at accurately recovering the large correlation effects of the outer-core d electrons.« less

  10. Radium-223 in the treatment of osteoblastic metastases: a critical clinical review.

    PubMed

    Humm, John L; Sartor, Oliver; Parker, Chris; Bruland, Oyvind S; Macklis, Roger

    2015-04-01

    The element radium (Ra) was discovered by the Curies in 1898 and within a decade was in broad scientific testing for the management of several forms of cancer. The compound was known to give rise to a series of both high-energy particulate and penetrating γ-emissions. The latter found an important role in early 20th century brachytherapy applications, but the short-range α-particles seemed much less useful. Although highly cytotoxic when released within a few cell diameters of critical cell nuclei, the dense double-strand break damage was poorly repaired, and concerns regarding treatment-related toxicities and secondary malignancies halted clinical development. Moreover, the most common isotope of Ra has an exceptionally long half-life (>1600 years for (226)Ra) that proved daunting when aiming for a systemic cancer therapy. Fortunately, other radium isotopes have more convenient half-lives while still producing cytotoxic α particles. Radium-223 dichloride has a half-life of 11.4 days, and this isotope was identified as an excellent candidate for radionuclide therapy of cancers metastatic to bone. The calcium-mimetic chemical properties of the radium allowed intravenous infusion with rapid uptake to sites of new bone formation. The highly efficient bone localization suggested a potential therapeutic role for osteoblastic bone metastases, and a series of phase 1, 2, and 3 clinical trials was undertaken to explore this possibility. This series of clinical explorations culminated in the ALSYMPCA trial, an international, placebo-controlled, phase 3 study that accrued 921 symptomatic men with bone-metastatic, castrate-resistant prostate cancer. Results of this trial demonstrated a prolongation of overall survival, and regulatory agencies around the world have now approved this product as a treatment for advanced prostate cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. The preparation, characterisation and in vitro cytotoxicity of potentially chemotherapeutic heterobimetallic complexes containing early and late transition metals.

    PubMed

    Wedgwood, Janet L; Kresinski, Roman A; Merry, Stephen; Platt, Andrew W G

    2003-06-01

    The reactions of phosphine Ph(2)P(CH(2))(2)SO(3)Na with Cp(2)M'Cl(2) (M'=Ti, Zr) in aqueous solution give the metallophosphines, Cp(2)Ti(OSO(2)(CH(2))(2)PPh(2))(2) (Cp=cyclopentadienyl) and CpZr(OH)(OSO(2)(CH(2))(2)PPh(2))(2). These react with CODM"Cl(2) (M"=Pd, Pt) (COD=1,5-cyclooctadiene) in dichloromethane to give heterobimetallic complexes Cp(2)Ti(OSO(2)(CH(2))(2)PPh(2))(2)M"Cl(2) and CpZr(OH)(OSO(2)(CH(2))(2) PPh(2))(2)M"Cl(2) respectively. The compounds are characterised by infrared and NMR spectroscopies and elemental analysis. Electrospray mass spectra of the complexes are reported and compared to those of Cp(2)M'Cl(2) in water and dimethylsulfoxide (DMSO). For zirconocene dichloride and its product heterobimetallic complexes, the addition of ethylenediamine tetraacetic acid disodium salt (Na(2)H(2)EDTA) was found to be an effective ionisation enhancement agent for the electrospray mass spectral studies. Cytotoxicity studies for the previously reported Cl(2)Pt(PPh(2)(CH(2))(2)SO(3)H)(2).3.5H(2)O (Wedgwood et al., Inorg. Chim. Acta 290 (1999) 189), and the compounds Cp(2)Ti(OSO(2)(CH(2))(2) PPh(2))(2).1.5H(2)O and Cp(2)Ti(OSO(2)(CH(2))(2)PPh(2))(2)PtCl(2).4H(2)O reported here, have been evaluated by colony formation assay against cisplatin-sensitive and -resistant cell lines L929 and L929/R to highlight potential chemotherapeutic activity. The compound Cl(2)Pt(PPh(2)(CH(2))(2)SO(3)H)(2).3.5H(2)O overcomes cisplatin resistance.

  12. Axially substituted silicon(IV) phthalocyanine and its quaternized derivative as photosensitizers towards tumor cells and bacterial pathogens.

    PubMed

    Ömeroğlu, İpek; Kaya, Esra Nur; Göksel, Meltem; Kussovski, Vesselin; Mantareva, Vanya; Durmuş, Mahmut

    2017-10-15

    Axially di-(alpha,alpha-diphenyl-4-pyridylmethoxy) silicon(IV) phthalocyanine (3) and its quaternized derivative (3Q) were synthesized and tested as photosensitizers against tumor and bacterial cells. These new phthalocyanines were characterized by elemental analysis, and different spectroscopic methods such as FT-IR, UV-Vis, MALDI-TOF and 1 H NMR. The photophysical properties such as absorption and fluorescence, and the photochemical properties such as singlet oxygen generation of both phthalocyanines were investigated in solutions. The obtained values were compared to the values obtained with unsubstituted silicon(IV) phthalocyanine dichloride (SiPcCl 2 ). The addition of two di-(alpha,alpha-diphenyl-4-pyridylmethanol) groups as axial ligands showed an improvement of the photophysical and photochemical properties and an increasement of the singlet oxygen quantum yield (Φ Δ ) from 0.15 to 0.33 was determined. The photodynamic efficacy of synthesized photosensitizers (3 and 3Q) were evaluated with promising photocytotoxicity (17% cell survival for 3 and 28% for 3Q) against the cervical cancer cell line (HeLa). The photodynamic inactivation of pathogenic bacterial strains Streptococcus mutans, Staphylococcus aureus, and Pseudomonas aeruginosa suggested a high susceptibility with quaternized derivative (3Q). The both Gram-positive bacterial strains were fully photoinactivated with 11μM 3Q and mild light dose 50J.cm -2 . In case of P. aeruginosa the effect was negligible for concentrations up to 22μM 3Q and light dose 100J.cm -2 . The results suggested that the novel axially substituted silicon(IV) phthalocyanines have promising characteristic as photosensitizer towards tumor cells. The quaternized derivative 3Q has high potential for photoinactivation of pathogenic bacterial species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Enhanced elemental mercury removal from coal-fired flue gas by sulfur-chlorine compounds.

    PubMed

    Yan, Nai-Qiang; Qu, Zan; Chi, Yao; Qiao, Shao-Hua; Dod, Ray L; Chang, Shih-Ger; Miller, Charles

    2009-07-15

    Oxidation of Hg(0) with any oxidant or converting itto a particle-bound form can facilitate its removal. Two sulfur-chlorine compounds, sulfur dichloride (SCl2) and sulfur monochloride (S2Cl2), were investigated as oxidants for Hg(0) by gas-phase reaction and by surface-involved reactions in the presence of flyash or activated carbon. The gas-phase reaction between Hg(0) and SCl2 is shown to be more rapid than the gas-phase reaction with chlorine, and the second order rate constant was 9.1 (+/- 0.5) x 10(-18) mL-molecules(-1) x s(-1) at 373 K. The presence of flyash or powdered activated carbon in flue gas can substantially accelerate the reaction. The predicted Hg(0) removal is about 90% with 5 ppm SCl2 or S2Cl2 and 40 g/m3 of flyash in flue gas. The combination of activated carbon and sulfur-chlorine compounds is an effective alternative. We estimate that coinjection of 3-5 ppm of SCl2 (or S2Cl2) with 2-3 Lb/MMacf of untreated Darco-KB is comparable in efficiency to the injection of 2-3 Lb/MMacf Darco-Hg-LH. Extrapolation of kinetic results also indicates that 90% of Hg(0) can be removed if 3 Lb/MMacf of Darco-KB pretreated with 3% of SCl2 or S2Cl2 is used. Mercuric sulfide was identified as one of the principal products of the Hg(0)/SCl2 or Hg(0)/S2Cl2 reactions. Additionally, about 8% of SCl2 or S2Cl2 in aqueous solutions is converted to sulfide ions, which would precipitate mercuric ion from FGD solution.

  14. Radium-223 in the Treatment of Osteoblastic Metastases: A Critical Clinical Review

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

    Humm, John L.; Sartor, Oliver; Parker, Chris

    2015-04-01

    The element radium (Ra) was discovered by the Curies in 1898 and within a decade was in broad scientific testing for the management of several forms of cancer. The compound was known to give rise to a series of both high-energy particulate and penetrating γ-emissions. The latter found an important role in early 20th century brachytherapy applications, but the short-range α-particles seemed much less useful. Although highly cytotoxic when released within a few cell diameters of critical cell nuclei, the dense double-strand break damage was poorly repaired, and concerns regarding treatment-related toxicities and secondary malignancies halted clinical development. Moreover, themore » most common isotope of Ra has an exceptionally long half-life (>1600 years for {sup 226}Ra) that proved daunting when aiming for a systemic cancer therapy. Fortunately, other radium isotopes have more convenient half-lives while still producing cytotoxic α particles. Radium-223 dichloride has a half-life of 11.4 days, and this isotope was identified as an excellent candidate for radionuclide therapy of cancers metastatic to bone. The calcium-mimetic chemical properties of the radium allowed intravenous infusion with rapid uptake to sites of new bone formation. The highly efficient bone localization suggested a potential therapeutic role for osteoblastic bone metastases, and a series of phase 1, 2, and 3 clinical trials was undertaken to explore this possibility. This series of clinical explorations culminated in the ALSYMPCA trial, an international, placebo-controlled, phase 3 study that accrued 921 symptomatic men with bone-metastatic, castrate-resistant prostate cancer. Results of this trial demonstrated a prolongation of overall survival, and regulatory agencies around the world have now approved this product as a treatment for advanced prostate cancer.« less

  15. A Candidate Trans-acting Modulator of Fetal Hemoglobin Gene Expression in the Arab-Indian Haplotype of Sickle Cell Anemia

    PubMed Central

    Vathipadiekal, Vinod; Farrell, John J.; Wang, Shuai; Edward, Heather L.; Shappell, Heather; Al-Rubaish, A.M.; Al-Muhanna, Fahad; Naserullah, Z.; Alsuliman, A.; Qutub, Hatem Othman; Simkin, Irene; Farrer, Lindsay A.; Jiang, Zhihua; Luo, Hong-Yuan; Huang, Shengwen; Mostoslavsky, Gustavo; Murphy, George J.; Patra, Pradeep.K.; Chui, David H.K.; Alsultan, Abdulrahman; Al-Ali, Amein K.; Sebastiani, Paola.; Steinberg, Martin. H.

    2016-01-01

    Fetal hemoglobin (HbF) levels are higher in the Arab-Indian (AI) β-globin gene haplotype of sickle cell anemia compared with African-origin haplotypes. To study genetic elements that effect HbF expression in the AI haplotype we completed whole genome sequencing in 14 Saudi AI haplotype sickle hemoglobin homozygotes—seven selected for low HbF (8.2±1.3%) and seven selected for high HbF (23.5±.2.6%). An intronic single nucleotide polymorphism (SNP) in ANTXR1, an anthrax toxin receptor (chromosome 2p13), was associated with HbF. These results were replicated in two independent Saudi AI haplotype cohorts of 120 and 139 patients, but not in 76 Saudi Benin haplotype, 894 African origin haplotype and 44 Arab Indian haplotype patients of Indian descent, suggesting that this association is effective only in the Saudi AI haplotype background. ANTXR1 variants explained 10% of the HbF variability compared with 8% for BCL11A. These two genes had independent, additive effects on HbF and together explained about 15% of HbF variability in Saudi AI sickle cell anemia patients. ANTXR1 was expressed at mRNA and protein levels in erythroid progenitors derived from induced pluripotent stem cells (iPSCs) and CD34+ cells. As CD34+ cells matured and their HbF decreased ANTXR1 expression increased; as iPSCs differentiated and their HbF increased, ANTXR1 expression decreased. Along with elements in cis to the HbF genes, ANTXR1 contributes to the variation in HbF in Saudi AI haplotype sickle cell anemia and is the first gene in trans to HBB that is associated with HbF only in carriers of the Saudi AI haplotype. PMID:27501013

  16. Novel axially carborane-cage substituted silicon phthalocyanine photosensitizer; synthesis, characterization and photophysicochemical properties

    NASA Astrophysics Data System (ADS)

    Atmaca, Göknur Yaşa; Dizman, Cemil; Eren, Tarık; Erdoğmuş, Ali

    2015-02-01

    The novel axially dicarborane substituted silicon (IV) (SiPc-DC) phthalocyanine was synthesized by treating silicon phthalocyanine dichloride SiPc(Cl)2 (SiPc) with o-Carborane monool. The compound was characterized by mass spectrometry, UV-Vis, FT-IR, 1H and 11B Nuclear Magnetic Resonance Spectroscopy (NMR). Spectral, photophysical (fluorescence quantum yield) and photochemical (singlet oxygen (ΦΔ) and photodegradation quantum yield (Φd)) properties of the complex were reported in different solutions (Dimethyl sulfoxide (DMSO), Dimethylformamide (DMF) and Toluene). The results of spectral measurements showed that both SiPc and carborane cage can have potential to be used as sensitizers in photodynamic therapy (PDT) and boron neutron capture therapy (BNCT) by their singlet oxygen efficiencies (ΦΔ = 0.41, 0.39).

  17. Synthesis of novel E-2-chlorovinyltellurium compounds based on the stereospecific anti-addition of tellurium tetrachloride to acetylene.

    PubMed

    Musalova, Maria V; Potapov, Vladimir A; Amosova, Svetlana V

    2012-05-15

    The reaction of tellurium tetrachloride with acetylene proceeds in a stereospecific anti-addition manner to afford the novel products E-2-chlorovinyltellurium trichloride and E,E-bis(2-chlorovinyl)tellurium dichloride. Reaction conditions for the selective preparation of each of these products were found. The latter was obtained in 90% yield in CHCl(3) under a pressure of acetylene of 10-15 atm, whereas the former product was formed in up to 72% yield in CCl(4) under a pressure of acetylene of 1-3 atm. Synthesis of the previously unknown E,E-bis(2-chlorovinyl) telluride, E,E-bis(2-chlorovinyl) ditelluride, E-2-chlorovinyl 1,2,2-trichloroethyl telluride and E,E-bis(2-chlorovinyl)-tellurium dibromide is described.

  18. Gas chromatographic determination of fumigant residues in stored grains, using isooctane partitioning and dual column packings.

    PubMed

    Daft, J L

    1983-03-01

    A gas chromatographic (GC) procedure for determining fumigants in grains was developed. Fumigants were leached from grain samples with the official AOAC method using acetone-water (5 + 1). They were then partitioned from the leachate with isooctane, yielding a dry, stable extract that was analyzed by GC. Fortified sample recoveries ranged from 90 to 100%. Two GC columns were used, 20% OV-101 and 20% OV-225/20% OV-17 (2 + 1). These columns gave dissimilar retention profiles and baseline resolution for the 7 fumigants investigated: chloroform, ethylene dichloride, carbon tetrachloride, trichloroethylene, chloropicrin, ethylene dibromide, and tetrachloroethylene. Further tests showed that grain samples could be screened for fumigant residues by direct injection of the acetone-water leachates obtained using the AOAC method.

  19. Trace elements in native and transplanted Fontinalis antipyretica and Platyhypnidium riparioides from rivers polluted by uranium mining.

    PubMed

    Kosior, Grzegorz; Steinnes, Eiliv; Samecka-Cymerman, Aleksandra; Lierhagen, Syverin; Kolon, Krzysztof; Dołhańczuk-Śródka, Agnieszka; Ziembik, Zbigniew

    2017-03-01

    The past uranium/polymetallic mining activities in the Sudety (SW Poland) left abandoned mines, pits, and dumps of waste rocks with trace elements and radionuclides which may erode or leach out and create a potential risk for the aquatic ecosystem, among others. In the present work four rivers affected by effluents from such mines were selected to evaluate the application of aquatic mosses for the bioindication of 56 elements. Naturally growing F. antipyretica and P. riparioides were compared with transplanted samples of the same species. The results demonstrate serious pollution of the examined rivers, especially with As, Ba, Fe, Mn, Pb, Ti, U and Zn, reaching extremely high concentrations in native moss samples. In the most polluted rivers native F. antipyretica and P. riparioides samples showed significantly higher concentrations of As, Ba, Cu, Fe, La, Nd, Ni, Pb, U and Zn than corresponding transplanted samples, whereas at less polluted sites a reverse situation was sometimes observed. Transplanted moss moved from clean to extremely polluted rivers probably protects itself against the accumulation of toxic elements by reducing their uptake. Selection of native or transplanted F. antipyretica and P. riparioides depended on the pollution load. Copyright © 2016. Published by Elsevier Ltd.

  20. Orbifold E-functions of dual invertible polynomials

    NASA Astrophysics Data System (ADS)

    Ebeling, Wolfgang; Gusein-Zade, Sabir M.; Takahashi, Atsushi

    2016-08-01

    An invertible polynomial is a weighted homogeneous polynomial with the number of monomials coinciding with the number of variables and such that the weights of the variables and the quasi-degree are well defined. In the framework of the search for mirror symmetric orbifold Landau-Ginzburg models, P. Berglund and M. Henningson considered a pair (f , G) consisting of an invertible polynomial f and an abelian group G of its symmetries together with a dual pair (f ˜ , G ˜) . We consider the so-called orbifold E-function of such a pair (f , G) which is a generating function for the exponents of the monodromy action on an orbifold version of the mixed Hodge structure on the Milnor fibre of f. We prove that the orbifold E-functions of Berglund-Henningson dual pairs coincide up to a sign depending on the number of variables and a simple change of variables. The proof is based on a relation between monomials (say, elements of a monomial basis of the Milnor algebra of an invertible polynomial) and elements of the whole symmetry group of the dual polynomial.

  1. P-Element Insertion Alleles of Essential Genes on the Third Chromosome of Drosophila Melanogaster: Correlation of Physical and Cytogenetic Maps in Chromosomal Region 86e-87f

    PubMed Central

    Deak, P.; Omar, M. M.; Saunders, RDC.; Pal, M.; Komonyi, O.; Szidonya, J.; Maroy, P.; Zhang, Y.; Ashburner, M.; Benos, P.; Savakis, C.; Siden-Kiamos, I.; Louis, C.; Bolshakov, V. N.; Kafatos, F. C.; Madueno, E.; Modolell, J.; Glover, D. M.

    1997-01-01

    We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover ~25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven ``supercontigs'' that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the αγ element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms. PMID:9409831

  2. Statistical Properties of Photospheric Magnetic Elements Observed by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory

    NASA Astrophysics Data System (ADS)

    Javaherian, M.; Safari, H.; Dadashi, N.; Aschwanden, M. J.

    2017-11-01

    Magnetic elements of the solar surface are studied (using the 6173 Å Fe i line) in magnetograms recorded with the high-resolution Solar Dynamics Observatory (SDO)/ Helioseismic and Magnetic Imager (HMI). To extract some statistical and physical properties of these elements ( e.g. filling factors, magnetic flux, size, and lifetimes), we employed the region-based method called Yet Another Feature Tracking Algorithm ( YAFTA). An area of 400^''×400^'' was selected to investigate the magnetic characteristics in 2011. The correlation coefficient between filling factors of negative and positive polarities is 0.51. A broken power-law fit was applied to the frequency distribution of size and flux. Exponents of the power-law distributions for sizes smaller and greater than 16 arcsec2 were found to be -2.24 and -4.04, respectively. The exponents of power-law distributions for fluxes lower and greater than 2.63× 10^{19} Mx were found to be -2.11 and -2.51, respectively. The relationship between the size [S] and flux [F] of elements can be expressed by a power-law behavior of the form of S∝ F^{0.69}. The lifetime and its relationship with the flux and size of quiet-Sun (QS) elements during three days were studied. The code detected patches with lifetimes of about 15 hours, which we call long-duration events. We found that more than 95% of the magnetic elements have lifetimes shorter than 100 minutes. About 0.05% of the elements had lifetimes of more than six hours. The relationships between size [S], lifetime [T], and flux [F] for patches in the QS yield power-law relationships S∝ T^{0.25} and F∝ T^{0.38}, respectively. Executing a detrended-fluctuation analysis of the time series of new emerged magnetic elements, we found a Hurst exponent of 0.82, which implies a long-range temporal correlation in the system.

  3. FLUORIDE VOLATILITY PROCESS FOR THE RECOVERY OF URANIUM

    DOEpatents

    Katz, J.J.; Hyman, H.H.; Sheft, I.

    1958-04-15

    The separation and recovery of uraniunn from contaminants introduced by neutron irradiation by a halogenation and volatilization method are described. The irradiated uranium is dissolved in bromine trifluoride in the liquid phase. The uranium is converted to the BrF/sub 3/ soluble urmium hexafluoride compound whereas the fluorides of certain contaminating elements are insoluble in liquid BrF/sub 3/, and the reaction rate of the BrF/sub 3/ with certain other solid uranium contamirnnts is sufficiently slower than the reaction rate with uranium that substantial portions of these contaminating elements will remain as solids. These solids are then separated from the solution by a distillation, filtration, or centrifugation step. The uranium hexafluoride is then separated from the balance of the impurities and solvent by one or more distillations.

  4. Molecular analysis of two genes between let-653 and let-56 in the unc-22(IV) region of Caenorhabditis elegans.

    PubMed

    Marra, M A; Prasad, S S; Baillie, D L

    1993-01-01

    A previous study of genomic organization described the identification of nine potential coding regions in 150 kb of genomic DNA from the unc-22(IV) region of Caenorhabditis elegans. In this study, we focus on the genomic organization of a small interval of 0.1 map unit bordered on the right by unc-22 and on the left by the left-hand breakpoints of the deficiencies sDf9, sDf19 and sDf65. This small interval at present contains a single mutagenically defined locus, the essential gene let-56. The cosmid C11F2 has previously been used to rescue let-56. Therefore, at least some of C11F2 must reside in the interval. In this paper, we report the characterization of two coding elements that reside on C11F2. Analysis of nucleotide sequence data obtained from cDNAs and cosmid subclones revealed that one of the coding elements closely resembles aromatic amino acid decarboxylases from several species. The other of these coding elements was found to closely resemble a human growth factor activatable Na+/H+ antiporter. Paris of oligonucleotide primers, predicted from both coding elements, have been used in PCR experiments to position these coding elements between the left breakpoint of sDf19 and the left breakpoint of sDf65, between the essential genes let-653 and let-56.

  5. Autokinase activity of alpha-crystallin inhibits its specific interaction with the DOTIS element in the murine gamma D/E/F-crystallin promoter in vitro.

    PubMed

    Pietrowski, D; Graw, J

    1997-10-01

    In a previous report we demonstrated the in vitro interaction of alpha-crystallin with an element downstream of the transcriptional initiation site (DOTIS) of the murine gamma E-crystallin promoter (Pietrowski et al., 1994, Gene 144, 171-178). The aim of the present study was to investigate the influence of phosphorylation on this particular interaction. We could demonstrate that the autophosphorylation of alpha-crystallin leads to a complete loss of interaction with the DOTIS element, however, PKA-dependent phosphorylation of alpha-crystallin is without effect on the interaction. It is hypothesized that the autophosphorylation of alpha-crystallin might be involved in regulatory mechanisms of the murine gamma D/E/F-crystallin gene expression.

  6. Valence State Partitioning of Cr and V Between Olivine-Melt and Pyroxene-Melt in Experimental Basalts of a Eucritic Composition

    NASA Technical Reports Server (NTRS)

    Karner, J. M.; Jones, J. H.; Le, L.

    2017-01-01

    The partitioning of multivalent elements in basaltic systems can elucidate the oxygen fugacity (fO2) conditions under which basalts formed on planetary bodies (Earth, Moon, Mars, asteroids). Chromium and V are minor and trace elements in basaltic melts, partition into several minerals that crystallize from basaltic melts, exist in multiple valence states at differing fO2 conditions, and can therefore be used as oxybarometers for basaltic melts. Chromium is mostly 3+ in terrestrial basaltic melts at relatively high fO2 values (= IW+3.5), and mostly 2+ in melts at low fO2 values (= IW-1), such as those on the Moon and some asteroids. At intermediate fO2s, (i.e., IW-1 to IW+3.5), basaltic melts contain both Cr3+ and Cr2+. Vanadium in basaltic melts is mostly 4+ at high fO2, mostly 3+ at low fO2, and a mix of V3+ and V4+ at intermediate fO2 con-ditions. Understanding the partitioning of Cr and V into silicate phases with changing fO2 is therefore critical to the employment of Cr and V oxybarometers. In this abstract we examine the equilibrium partitioning of Cr and V between olivine/melt and pyroxene/melt in experimental charges of a eucritic composition produced at differing fO2 conditions. This study will add to the experimental data on DCr and DV (i.e., olivine/melt, pyroxene/melt) at differing fO2, and in turn these D values will be used to assess the fO2 of eucrite basalts and perhaps other compositionally similar planetary basalts.

  7. 77 FR 29904 - Approval and Promulgation of Implementation Plans; Oregon: Infrastructure Requirements for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ...: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M). DATES: This action is effective... elements for the 1997 8-hour ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), and (M... 1997 ozone NAAQS: (A), (B), (C), (D)(ii), (E), (F), (G), (H), (J), (K), (L), (M). EPA is taking no...

  8. Appendix F : finite element analysis of end region.

    DOT National Transportation Integrated Search

    2013-03-01

    FE (finite element) modeling was conducted to 1) provide a better understanding of the : elastic behavior of the end region prior to cracking and 2) to evaluate the effects of bearing pad : stiffness and width on end region elastic stresses. The FEA ...

  9. The Effects of Using Solar Radiation Pressure to Alleviate Fuel Requirements for Orbit Changing and Maintenance of the DSCS II F-13 Satellite

    DTIC Science & Technology

    2006-03-01

    Owens J. “A Set of Modified Equinoctial Orbit Elements ,” Celestial Mechanics, 36 :409–419 (1985). 35. Wie B. Space Vehicle Dynamics and Control...14 MEE modified equinoctial elements . . . . . . . . . . . . . . . . . . . . . . . 14 TLE two-line element set ...satellite [32]. Vallado’s model will be incorporated into this thesis. 2.3.3 Modified Equinoctial Orbital Elements . For most astrodynamics problems, one of

  10. Spatial-Gain Improvement Resulting from Left/Right Discriminating Elements of an Underwater Towed Array

    DTIC Science & Technology

    1981-09-15

    DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY rsil RONALD A. WAGSTAFF and PIETRO MANASCA D TIC": L• ’" .... 4"•’.,, 15 SEPTEMBER 1981...IMPROVEMENT RESULTING FROM LEFT/RIGHT DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY by Ronald A. Wagstaff and Pietro Zanasca 15 September 1981 F...RESULTING FROM LEFT/RIGHT DISCRIMINATING ELEMENTS OF AN UNDERWATER TOWED ARRAY by Ronald A. Wagstaff and Pietro Zanasca ABSTRACT The improvement in

  11. Test and Evaluation of the Navy Technical Information Presentation System (NTIPS) F-14A Field Test Results

    DTIC Science & Technology

    1988-09-01

    Test and Evaluation Report Test and Evaluation of the Navy Technical Information Presentation System (NTIPS) F-14A Field Test Results by .0 Joseph J...PROGRAM PROJECT TASK WORK UNIT Washington, D.C. 20361 ELEMENT NO. NO. NO. ACCESSION NO. OMN 1820 11. TITLE (Include Security Classification) TEST AND...EVALUATION OF THE NAVY TECHNICAL INFORMATION PRESENTATION SYSTEM (NTIPS) F-14A FIELD TEST RESULTS 12. PERSONAL AUTHOR(S) Fuller, Joseph F. (DTRC) Post

  12. Erosion of fluorinated diamond-like carbon films by exposure to soft X-rays

    NASA Astrophysics Data System (ADS)

    Kanda, Kazuhiro; Takamatsu, Hiroki; Miura-Fujiwara, Eri; Akasaka, Hiroki; Saiga, Akihiro; Tamada, Koji

    2018-04-01

    The effects of soft X-ray irradiation on fluorinated diamond-like carbon (F-DLC) films were investigated using synchrotron radiation (SR). The Vickers hardness of the F-DLC films substantially increased from an initial value of about 290 to about 800 HV at a dose of 50 mA·h and the remained constant at about 1100 HV at doses of more than 300 mA·h. This dose dependence was consistent with those of the film thickness and elemental composition. The depth profile of the elemental composition inside each F-DLC film obtained by the measurement of the X-ray photoelectron spectrum (XPS) during sputtering showed that the composition ratio of fluorine was approximately constant from the surface to the neighborhood of the substrate. Namely, fluorine atoms were desorbed by SR irradiation from not only the surface but also the substrate neighborhood. Modification by SR irradiation was found to occur in the entire F-DLC film of about 200 nm thickness.

  13. Uranium mineralization in fluorine-enriched volcanic rocks

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

    Burt, D.M.; Sheridan, M.F.; Bikun, J.

    1980-09-01

    Several uranium and other lithophile element deposits are located within or adjacent to small middle to late Cenozoic, fluorine-rich rhyolitic dome complexes. Examples studied include Spor Mountain, Utah (Be-U-F), the Honeycomb Hills, Utah (Be-U), the Wah Wah Mountains, Utah (U-F), and the Black Range-Sierra Cuchillo, New Mexico (Sn-Be-W-F). The formation of these and similar deposits begins with the emplacement of a rhyolitic magma, enriched in lithophile metals and complexing fluorine, that rises to a shallow crustal level, where its roof zone may become further enriched in volatiles and the ore elements. During initial explosive volcanic activity, aprons of lithicrich tuffsmore » are erupted around the vents. These early pyroclastic deposits commonly host the mineralization, due to their initial enrichment in the lithophile elements, their permeability, and the reactivity of their foreign lithic inclusions (particularly carbonate rocks). The pyroclastics are capped and preserved by thick topaz rhyolite domes and flows that can serve as a source of heat and of additional quantities of ore elements. Devitrification, vapor-phase crystallization, or fumarolic alteration may free the ore elements from the glassy matrix and place them in a form readily leached by percolating meteoric waters. Heat from the rhyolitic sheets drives such waters through the system, generally into and up the vents and out through the early tuffs. Secondary alteration zones (K-feldspar, sericite, silica, clays, fluorite, carbonate, and zeolites) and economic mineral concentrations may form in response to this low temperature (less than 200 C) circulation. After cooling, meteoric water continues to migrate through the system, modifying the distribution and concentration of the ore elements (especially uranium).« less

  14. Mineral Systems, Their Types, and Distribution in Nature: 2. Products of Contemporary Fumarole Activity at Tolbachik Volcano (Russia) and Vulcano (Italy)

    NASA Astrophysics Data System (ADS)

    Krivovichev, V. G.; Charykova, M. V.

    2017-12-01

    The number of mineral species in which a certain chemical element is species-defining (according to statistical data up to 2015) has been specified. Seventy chemical elements are species-defining for 5044 minerals. The following chemical elements lead in the composition of minerals (number of mineral species in parentheses): oxygen (4115), hydrogen (2800), silicon (1471), calcium (1167), sulfur (1056), aluminium (985), sodium (949), iron (945), copper (636), phosphorus (597), arsenic (594), and magnesium (571). The distribution of mineral species by various systems in the products of contemporary fumarole activity at two volcanoes, Tolbachik in Kamchatka, Russia, and Vulcano in Sicily, Italy, has been compared. These locations were also compared for the distribution of species-defining elements. Thus, it has been determined that in fumaroles of both volcanoes, Tl, S, Cl, F and Na are "excessive," present in minerals in elevated amounts, whereas H, Ca, Fe, and Mn are "deficient." The abundance of Cu, Se, V, Mg, Zn, As, and F in minerals at Tolbachik is higher than the global mean values of these elements in the Earth's crust, whereas the abundance is significantly lower at Vulcano. Sn, I, Br, K, Pb, Al, Fe, and Bi demonstrate the opposite behavior. Comparison of the Yadovitaya and Arsenatnaya fumaroles at the Tolbachik volcano showed that the products of the former are richer in H, Cl, Cu, S, K, O, Al, Fe, and Pb, and poorer in As, Ca, Mg, and Na as species-defining elements. In addition, V-and Mo-bearing minerals are found only at Yadovitaya, whereas minerals containing F, Ti, B, Te, and Zn are known only at Arsenatnaya.

  15. Analysis of traditional Tibetan pills

    NASA Astrophysics Data System (ADS)

    Cesnek, Martin; Štefánik, Milan; Miglierini, Marcel; Kmječ, Tomáš; Sklenka, L'ubomír

    2017-11-01

    Traditional Tibetan medicine starts to be a very popular complementary medicine in USA and Europe. These pills contain many elements essential for the human body. However, they might also contain heavy metals such as mercury, iron, arsenic, etc. This paper focuses on elemental composition of two Tibetan pills and investigation of forms of iron in them. X-ray fluorescence spectroscopy and neutron activation analysis identified the presence of several heavy metals such as mercury, iron and copper. Mőssbauer spectroscopy revealed the possible presence of α - F e 2 O 3(hematite) and α - F e O O H(goethite) in both of the investigated samples.

  16. Method for Derivatization and Detection of Chemical Weapons Convention Related Sulfur Chlorides via Electrophilic Addition with 3-Hexyne.

    PubMed

    Goud, D Raghavender; Pardasani, Deepak; Purohit, Ajay Kumar; Tak, Vijay; Dubey, Devendra Kumar

    2015-07-07

    Sulfur monochloride (S2Cl2) and sulfur dichloride (SCl2) are important precursors of the extremely toxic chemical warfare agent sulfur mustard and classified, respectively, into schedule 3.B.12 and 3.B.13 of the Chemical Weapons Convention (CWC). Hence, their detection and identification is of vital importance for verification of CWC. These chemicals are difficult to detect directly using chromatographic techniques as they decompose and do not elute. Until now, the use of gas chromatographic approaches to follow the derivatized sulfur chlorides is not reported in the literature. The electrophilic addition reaction of sulfur monochloride and sulfur dichloride toward 3-hexyne was explored for the development of a novel derivatization protocol, and the products were subjected to gas chromatography-mass spectrometric (GC-MS) analysis. Among various unsaturated reagents like alkenes and alkynes, symmetrical alkyne 3-hexyne was optimized to be the suitable derivatizing agent for these analytes. Acetonitrile was found to be the suitable solvent for the derivatization reaction. The sample preparation protocol for the identification of these analytes from hexane spiked with petrol matrix was also optimized. Liquid-liquid extraction followed by derivatization was employed for the identification of these analytes from petrol matrix. Under the established conditions, the detection and quantification limits are 2.6 μg/mL, 8.6 μg/mL for S2Cl2 and 2.3 μg/mL, 7.7 μg/mL for SCl2, respectively, in selected ion monitoring (SIM) mode. The calibration curve had a linear relationship with y = 0.022x - 0.331 and r(2) = 0.992 for the working range of 10 to 500 μg/mL for S2Cl2 and y = 0.007x - 0.064 and r(2) = 0.991 for the working range of 10 to 100 μg/mL for SCl2, respectively. The intraday RSDs were between 4.80 to 6.41%, 2.73 to 6.44% and interday RSDs were between 2.20 to 7.25% and 2.34 to 5.95% for S2Cl2 and SCl2, respectively.

  17. A Biodistribution and Toxicity Study of Cobalt Dichloride-N-Acetyl Cysteine in an Implantable MRI Marker for Prostate Cancer Treatment

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

    Frank, Steven J., E-mail: sjfrank@mdanderson.org; Johansen, Mary J.; Martirosyan, Karen S.

    2013-03-15

    Purpose: C4, a cobalt dichloride-N-acetyl cysteine complex, is being developed as a positive-signal magnetic resonance imaging (MRI) marker to localize implanted radioactive seeds in prostate brachytherapy. We evaluated the toxicity and biodistribution of C4 in rats with the goal of simulating the systemic effects of potential leakage from C4 MRI markers within the prostate. Methods and Materials: 9-μL doses (equivalent to leakage from 120 markers in a human) of control solution (0.9% sodium chloride), 1% (proposed for clinical use), and 10% C4 solution were injected into the prostates of male Sprague-Dawley rats via laparotomy. Organ toxicity and cobalt disposition inmore » plasma, tissues, feces, and urine were evaluated. Results: No C4-related morbidity or mortality was observed in the biodistribution arm (60 rats). Biodistribution was measurable after 10% C4 injection: cobalt was cleared rapidly from periprostatic tissue; mean concentrations in prostate were 163 μg/g and 268 μg/g at 5 and 30 minutes but were undetectable by 60 minutes. Expected dual renal-hepatic elimination was observed, with percentages of injected dose recovered in tissues of 39.0 ± 5.6% (liver), >11.8 ± 6.5% (prostate), and >5.3 ± 0.9% (kidney), with low plasma concentrations detected up to 1 hour (1.40 μg/mL at 5-60 minutes). Excretion in urine was 13.1 ± 4.6%, with 3.1 ± 0.54% recovered in feces by 24 hours. In the toxicity arm, 3 animals died in the control group and 1 each in the 1% and 10% groups from surgical or anesthesia-related complications; all others survived to scheduled termination at 14 days. No C4-related adverse clinical signs or organ toxicity were observed. Conclusion: C4-related toxicity was not observed at exposures at least 10-fold the exposure proposed for use in humans. These data demonstrating lack of systemic toxicity with dual routes of elimination in the event of in situ rupture suggest that C4 warrants further investigation as an MRI marker for prostate brachytherapy.« less

  18. Role of the Diphosphine Chelate in Emissive, Charge-Neutral Iridium(III) Complexes.

    PubMed

    Liao, Jia-Ling; Devereux, Leon R; Fox, Mark A; Yang, Chun-Chieh; Chiang, Yu-Cheng; Chang, Chih-Hao; Lee, Gene-Hsiang; Chi, Yun

    2018-01-12

    A class of neutral tris-bidentate Ir III metal complexes incorporating a diphosphine as a chelate is prepared and characterized here for the first time. Treatment of [Ir(dppBz)(tht)Cl 3 ] (1, dppBz=1,2-bis(diphenylphosphino)benzene, tht=tetrahydrothiophene) with fppzH (3-trifluoromethyl-5-(2'-pyridyl)-1H-pyrazole) afforded the dichloride complexes, trans-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (2) and cis-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (3). The reaction of 3 with the dianionic chelate precursor, 5,5'-di(trifluoromethyl)-3,3'-bipyrazole (bipzH 2 ) or 5,5'-(1-methylethylidene)-bis(3-trifluoromethyl-1H-pyrazole) (mepzH 2 ), in DMF gave the tris-bidentate complex [Ir(dppBz)(fppz)(bipz)] (4) or [Ir(dppBz)(fppz)(mepz)] (5), respectively. In contrast, a hydride complex [Ir(dppBz)(fppz)(bipzH)H] (6) was isolated instead of 4 in protic solvent, namely: diethylene glycol monomethyl ether (DGME). All complexes 2-6 are luminescent in powder form and thin films where the dichlorides (2, 3) emit with maxima at 590-627 nm (orange) and quantum yields (QYs) up to 90 % whereas the tris-bidentate (4, 5) and hydride (6) complexes emit at 455-458 nm (blue) with QYs up to 70 %. Hybrid (time-dependent) DFT calculations showed considerable metal-to-ligand charge transfer contribution to the orange-emitting 2 and 3 but substantial ligand-centered 3 π-π* transition character in the blue-emitting 4-6. The dppBz does not participate in the radiative transitions in 4-6, but it provides the rigidity and steric bulk needed to promote the luminescence by suppressing the self-quenching in the solid state. Fabrication of an organic light-emitting diode (OLED) with dopant 5 gave a deep-blue CIE chromaticity of (0.16, 0.15). Superior blue emitters, which are vital in OLED applications, may be found in other neutral Ir III complexes containing phosphine chelates. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Speciation of the Potential Antitumor Agent Vanadocene Dichloride in the Blood Plasma and Model Systems.

    PubMed

    Sanna, Daniele; Ugone, Valeria; Micera, Giovanni; Pivetta, Tiziana; Valletta, Elisa; Garribba, Eugenio

    2015-09-08

    The speciation of the potential antitumor agent vanadocene dichloride ([Cp2VCl2], abbreviated with VDC) in the blood plasma was studied by instrumental (EPR, ESI-MS, MS-MS, and electronic absorption spectroscopy) and computational (DFT) methods. The behavior of VDC at pH 7.4 in aqueous solution, the interaction with the most important bioligands of the plasma (oxalate, carbonate, phosphate, lactate, citrate, histidine, and glycine among those with low molecular mass and transferrin and albumin between the proteins) was evaluated. The results suggest that [Cp2VCl2] transforms at physiological pH to [Cp2V(OH)2] and that only oxalate, carbonate, phosphate, and lactate are able to displace the two OH(-) ions to yield [Cp2V(ox)], [Cp2V(CO3)], [Cp2V(lactH(-1))], and [Cp2V(HPO4)]. The formation of the adducts with oxalate, carbonate, lactate, and hydrogen phosphate was confirmed also by ESI-MS and MS-MS spectra. The stability order is [Cp2V(ox)] ≫ [Cp2V(CO3)] > [Cp2V(lactH(-1))] > [Cp2V(HPO4)]. No interaction between VDC and plasma proteins was detected under our experimental conditions. Several model systems containing the bioligands (bL) in the same relative ratio as in the blood samples were also examined. Finally, the speciation of VDC in the plasma was studied. The results obtained show that the model systems behave as the blood plasma and indicate that when V concentration is low (10 μM) VDC is transported in the bloodstream as [Cp2V(ox)]; when V concentration is high (100 μM) oxalate binds only 9.2 μM of [Cp2V](2+), whereas the remaining part distributes between [Cp2V(CO3)] (main species) and [Cp2V(lactH(-1))] (minor species); and when V concentration is in the range 10-100 μM [Cp2V](2+) distributes between [Cp2V(ox)] and [Cp2V(CO3)].

  20. Low fat-containing elemental formula is effective for postoperative recovery and potentially useful for preventing chyle leak during postoperative early enteral nutrition after esophagectomy.

    PubMed

    Moro, Kazuki; Koyama, Yu; Kosugi, Shin-Ichi; Ishikawa, Takashi; Ichikawa, Hiroshi; Hanyu, Takaaki; Miura, Kohei; Nagahashi, Masayuki; Nakajima, Masato; Tatsuda, Kumiko; Tsuchida, Junko; Toshikawa, Chie; Ikarashi, Mayuko; Shimada, Yoshifumi; Sakata, Jun; Kobayashi, Takashi; Kameyama, Hitoshi; Wakai, Toshifumi

    2016-12-01

    Transthoracic esophagectomy using 3-field lymphadenectomy (TTE-3FL) for esophageal cancer is one of the most aggressive gastrointestinal surgeries. Early enteral nutrition (EN) for TTE-3FL patients is useful and valid for early recovery; however, EN using a fat-containing formula risks inducing chyle leak. In the present study, we retrospectively examined esophageal cancer patients treated byTTE-3FL and administered postoperative EN to elucidate the validity of lowering the fat levels in elemental formulas to prevent postoperative chyle leak and improve postoperative recovery. A total of 74 patients who received TTE-3FL for esophageal cancer were retrospectively examined. Patients were classified into two groups according to the type of postoperative EN: Group LF patients received a low-fat elemental formula, and Group F patients received a standard fat-containing polymeric formula. The following clinical factors were compared between the groups: EN start day, maximum EN calories administered, duration of respirator use, length of ICU stay, incidence of postoperative infectious complications, use of parenteral nutrition (PN), and incidence of postoperative chyle leak. Patients in Group LF were started on EN significantly earlier after surgery and they consumed significantly higher maximum EN calories compared to Group F patients (P < 0.01). Duration of respirator use and length of ICU stay were also significantly shorter, and TPN was used significantly less in Group LF compared to Group F (P < 0.05). Postoperative chyle leak was observed in six patients in total (8.1%); five patients in Group F and one patient in Group LF, although there was no significant difference in frequency of chyle leak per patient between Group LF and Group F. Early EN using low-fat elemental formula after esophagectomy with three-field lymphadenectomy was safe and valid for postoperative recovery and potentially useful in preventing chyle leak. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Pumped lithium loop test to evaluate advanced refractory metal alloys and simulated nuclear fuel elements

    NASA Technical Reports Server (NTRS)

    Brandenburf, G. P.; Hoffman, E. E.; Smith, J. P.

    1974-01-01

    The performance was determined of refractory metal alloys and uranium nitride fuel element specimens in flowing 1900F (1083C) lithium. The results demonstrate the suitability of the selected materials to perform satisfactorily from a chemical compatibility standpoint.

  2. 34. DETAILS AND SECTIONS OF SHIELDING TANK FUEL ELEMENT SUPPORT ...

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

    34. DETAILS AND SECTIONS OF SHIELDING TANK FUEL ELEMENT SUPPORT FRAME. F.C. TORKELSON DRAWING NUMBER 842-ARVFS-701-S-4. INEL INDEX CODE NUMBER: 075 0701 60 851 151978. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  3. High temperature ceramic composition for hydrogen retention

    DOEpatents

    Webb, R.W.

    1974-01-01

    A ceramic coating for H retention in fuel elements is described. The coating has relatively low thermal neutron cross section, is not readily reduced by H at 1500 deg F, is adherent to the fuel element base metal, and is stable at reactor operating temperatures. (JRD)

  4. Differential recruitment of the sensorimotor putamen and frontoparietal cortex during motor chunking in humans

    PubMed Central

    Wymbs, Nicholas F.; Bassett, Danielle S.; Mucha, Peter J.; Porter, Mason A.; Grafton, Scott T.

    2012-01-01

    Motor chunking facilitates movement production by combining motor elements into integrated units of behavior. Previous research suggests that chunking involves two processes: concatenation, aimed at the formation of motor-motor associations between elements or sets of elements; and segmentation, aimed at the parsing of multiple contiguous elements into shorter action sets. We used fMRI to measure the trial-wise recruitment of brain regions associated with these chunking processes as healthy subjects performed a cued sequence production task. A novel dynamic network analysis identified chunking structure for a set of motor sequences acquired during fMRI and collected on three days of training. Activity in the bilateral sensorimotor putamen positively correlated with chunk concatenation, whereas a left hemisphere frontoparietal network was correlated with chunk segmentation. Across subjects, there was an aggregate increase in chunk strength (concatenation) with training, suggesting that subcortical circuits play a direct role in the creation of fluid transitions across chunks. PMID:22681696

  5. Differential recruitment of the sensorimotor putamen and frontoparietal cortex during motor chunking in humans.

    PubMed

    Wymbs, Nicholas F; Bassett, Danielle S; Mucha, Peter J; Porter, Mason A; Grafton, Scott T

    2012-06-07

    Motor chunking facilitates movement production by combining motor elements into integrated units of behavior. Previous research suggests that chunking involves two processes: concatenation, aimed at the formation of motor-motor associations between elements or sets of elements, and segmentation, aimed at the parsing of multiple contiguous elements into shorter action sets. We used fMRI to measure the trial-wise recruitment of brain regions associated with these chunking processes as healthy subjects performed a cued-sequence production task. A dynamic network analysis identified chunking structure for a set of motor sequences acquired during fMRI and collected over 3 days of training. Activity in the bilateral sensorimotor putamen positively correlated with chunk concatenation, whereas a left-hemisphere frontoparietal network was correlated with chunk segmentation. Across subjects, there was an aggregate increase in chunk strength (concatenation) with training, suggesting that subcortical circuits play a direct role in the creation of fluid transitions across chunks. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. ToF-SIMS measurements with topographic information in combined images.

    PubMed

    Koch, Sabrina; Ziegler, Georg; Hutter, Herbert

    2013-09-01

    In 2D and 3D time-of-flight secondary ion mass spectrometric (ToF-SIMS) analysis, accentuated structures on the sample surface induce distorted element distributions in the measurement. The origin of this effect is the 45° incidence angle of the analysis beam, recording planar images with distortion of the sample surface. For the generation of correct element distributions, these artifacts associated with the sample surface need to be eliminated by measuring the sample surface topography and applying suitable algorithms. For this purpose, the next generation of ToF-SIMS instruments will feature a scanning probe microscope directly implemented in the sample chamber which allows the performance of topography measurements in situ. This work presents the combination of 2D and 3D ToF-SIMS analysis with topographic measurements by ex situ techniques such as atomic force microscopy (AFM), confocal microscopy (CM), and digital holographic microscopy (DHM). The concept of the combination of topographic and ToF-SIMS measurements in a single representation was applied to organic and inorganic samples featuring surface structures in the nanometer and micrometer ranges. The correct representation of planar and distorted ToF-SIMS images was achieved by the combination of topographic data with images of 2D as well as 3D ToF-SIMS measurements, using either AFM, CM, or DHM for the recording of topographic data.

  7. Effect of high-energy electron irradiation in an electron microscope column on fluorides of alkaline earth elements (CaF2, SrF2, and BaF2)

    NASA Astrophysics Data System (ADS)

    Nikolaichik, V. I.; Sobolev, B. P.; Zaporozhets, M. A.; Avilov, A. S.

    2012-03-01

    The effect of high-energy (150 eV) electron irradiation in an electron microscope column on crystals of fluorides of alkaline earth elements CaF2, SrF2, and BaF2 is studied. During structural investigations by electron diffraction and electron microscopy, the electron irradiation causes chemical changes in MF2 crystals such as the desorption of fluorine and the accumulation of oxygen in the irradiated area with the formation of oxide MO. The fluorine desorption rate increases significantly when the electron-beam density exceeds the threshold value of ˜2 × 103 pA/cm2). In BaF2 samples, the transformation of BaO into Ba(OH)2 was observed when irradiation stopped. The renewal of irradiation is accompanied by the inverse transformation of Ba(OH)2 into BaO. In the initial stage of irradiation of all MF2 compounds, the oxide phase is in the single-crystal state with a lattice highly matched with the MF2 matrix. When the irradiation dose is increased, the oxide phase passes to the polycrystalline phase. Gaseous products of MF2 destruction (in the form of bubbles several nanometers in diameter) form a rectangular array with a period of ˜20 nm in the sample.

  8. User Instructions for the EPIC-3 Code.

    DTIC Science & Technology

    1987-05-01

    MATERIAL CARDS FOR SOLIDS FROM LIBRARY (4M5 2F5,0) IMATLI 0 10AM IFAIL PFRAC[ EFAIL 5 MATERIAL CARDS FOR SOLUDS INPUT DATA: (415, 5X. F5.0. A4...21S, 15X, F5.0) LMAIL. 0 EFAIL 4 MATERIAL CARDS FOR CRUSHABLE SOLUDS INPUT DATA 1215.1l5Y, F5.0, A48/310.0W2(8F10.o)j MATL. 3 T EFAIL MATERIAL...elements must be achieved by the eroding interface algorithm, it is important that EFAIL (a material property) be much greater than ERODE. Master Definition

  9. Low Temperature Fluorination of Aerosol and Condensed Phase Sol Suspensions of Hydrocarbons Utilizing Elemental Fluorine.

    DTIC Science & Technology

    1980-04-01

    subambient temperature capability of our design . The aerosol fluorination system designed to produce a controlled , con- tinuous stream of aerosol...F3 H8 , 117 (68.9) C6F2H7 CN: D I Mixture CO: D I’’ Difluorocyclohexane Isomer (two nonequivalent CFR groups ) 1 H NMR no integration given 1 9F NMR: d...two nonequivalent CFH groups ) 1H NMR no integration given 19F NMR d? at 193.5 ppm (J = 106.8 Rz ?) 32 TABLE 7 (CONTINUED) MS: CI: 119 (1.4) C6F2

  10. Frequency tuning characteristics of a Q-switched Co:MgF2 laser

    NASA Technical Reports Server (NTRS)

    Lovold, S.; Moulton, P. F.; Killinger, D. K.; Menyuk, N.

    1985-01-01

    A tunable Q-switched Co:MgF2 laser has been developed for atmospheric remote sensing applications. Frequency tuning is provided by a quartz etalon and a specially designed three-element birefringent filter covering the whole gain bandwidth of the Co:MgF2 laser. The laser has good temporal and spectral characteristics, with an emission linewidth of approximately 3 GHz (0.1 per cm).

  11. Toward New Magnesium Alloy Design - Theoretical and Experimental Studies of the Influence of Alloying Elements on Deformation Twinning

    DTIC Science & Technology

    2013-03-27

    Research Office (W911NF-12-1-0023). Ab initio calculations have been performed to study the effects of solute atoms on the c/a ratio of magnesium alloys ... effects of alloying elements on the c/a ratio of magnesium were performed. The most commonly and extensively used alloying elements such as Al, Mn, and... Magnesium Alloy Design - Theoretical and Experimental Studies of the Influence of Alloying Elements on Deformation Twinning M.F. Horstemeyer

  12. Jam Resistant Communications Systems Techniques

    DTIC Science & Technology

    1982-12-01

    ina rayo iteeet -- :."-,(constraint elements plus two resolution elements). •j, r,2 -- ’:." ~d c =0 .4 3 ),, dr l :3 .2X , dr 2 4 5 X @d -900 , s :33...E.K. Walton (Section VIII), and Dr. I.J. Gupta (Sections IX and X ). Mr. R.C. Taylor and R.W. Evans made significant contributions to all experimental...IN THE SAME CUT 190 E. CONCLUSIONS 200 F. REFERENCES 00 SECTION X ELEMENT PLACEMENT FOR ADAPTIVE ANTENNA ARRAYS 201 A. INTRODUCTION 201 B. THE ELEMENT

  13. Characterizing Response to Elemental Unit of Acoustic Imaging Noise: An fMRI Study

    PubMed Central

    Luh, Wen-Ming; Talavage, Thomas M.

    2010-01-01

    Acoustic imaging noise produced during functional magnetic resonance imaging (fMRI) studies can hinder auditory fMRI research analysis by altering the properties of the acquired time-series data. Acoustic imaging noise can be especially confounding when estimating the time course of the hemodynamic response (HDR) in auditory event-related fMRI (fMRI) experiments. This study is motivated by the desire to establish a baseline function that can serve not only as a comparison to other quantities of acoustic imaging noise for determining how detrimental is one's experimental noise, but also as a foundation for a model that compensates for the response to acoustic imaging noise. Therefore, the amplitude and spatial extent of the HDR to the elemental unit of acoustic imaging noise (i.e., a single ping) associated with echoplanar acquisition were characterized and modeled. Results from this fMRI study at 1.5 T indicate that the group-averaged HDR in left and right auditory cortex to acoustic imaging noise (duration of 46 ms) has an estimated peak magnitude of 0.29% (right) to 0.48% (left) signal change from baseline, peaks between 3 and 5 s after stimulus presentation, and returns to baseline and remains within the noise range approximately 8 s after stimulus presentation. PMID:19304477

  14. Fluoride Alters Serum Elemental (Calcium, Magnesium, Copper, and Zinc) Homeostasis Along with Erythrocyte Carbonic Anhydrase Activity in Fluorosis Endemic Villages and Restores on Supply of Safe Drinking Water in School-Going Children of Nalgonda District, India.

    PubMed

    Khandare, Arjun L; Validandi, Vakdevi; Boiroju, Naveen

    2018-02-17

    The present study aimed to determine the serum trace elements (copper (Cu), zinc (Zn), calcium (Ca), magnesium (Mg)) along with erythrocyte carbonic anhydrase (CA) activity and effect of intervention with safe drinking water for 5 years in the school children of fluorosis endemic area. For this purpose, three categories of villages were selected based on drinking water fluoride (F): Category I (control, F = 1.68 mg/L), category II (affected F = 3.77 mg/L), and category III (intervention village) where initial drinking water F was 4.51 mg/L, and since the last 5 years, they were drinking water containing < 1.0 mg/L F. The results revealed that urinary F was significantly (P < 0.05) higher in category II compared to categories I and III. A significant (P < 0.05) increase in serum Cu and Mg was observed in category II compared to category I. Serum Zn and Ca was significantly (P < 0.05) decreased in categories II and III compared to category I. The erythrocyte CA activity was decreased in the category II compared to category I. However, in the category III, erythrocyte CA activity was comparable to the control group. In conclusion, F exposure altered elemental homeostasis which has restored to some extent on intervention by safe drinking water for 5 years in school-going children.

  15. Genetic and molecular studies of a composite chromosomal element (Tn3705) containing a Tn916-modified structure (Tn3704) in Streptococcus anginosus F22.

    PubMed

    Clermont, D; Horaud, T

    1994-01-01

    The plasmid-free Streptococcus anginosus F22 contained a conjugative element, Tn3705, encoding resistance to erythromycin (Emr) and tetracycline-minocycline (Tcr-Mnr). We mapped a chromosomal region (> 52 kb) of F22, corresponding to the internal part of Tn3705. Molecular analysis of Tn3705 revealed it to be a composite structure: it included in its central part a transposon designated Tn3704 (20.3 kb +/- 0.5 kb), which had a modified structure in comparison with that of Tn916 and on which the Emr Tcr-Mn4 markers were localized. Tn3705 inserted from F22 into the chromosome of various streptococcal transconjugants as well as that of Enterococcus faecalis transconjugants without changing its structure. In contrast, from the chromosome of an E. faecalis::Tn3705 transconjugant only Tn3704 inserted, at various sites, into another E. faecalis chromosome. Sugar fermentations occurred after the insertion of Tn3704 into the chromosome of an asaccharolytic E. faecalis strain. Transposition of only Tn3704 from the chromosome of E. faecalis::Tn3705 onto pIP964, an E. faecalis hemolysin plasmid, yielded two different pIP964 derivatives. The size of the entire element Tn3705 was estimated to be about 70.0 kb by pulsed-field electrophoresis.

  16. An Embedded 4-Channel Receive-Only RF Coil Array for fMRI Experiments of the Somatosensory Pathway in Conscious Awake Marmosets at 7T

    PubMed Central

    Papoti, Daniel; Yen, Cecil Chern-Chyi; Mackel, Julie B.; Merkle, Hellmut; Silva, Afonso C.

    2014-01-01

    Functional Magnetic Resonance Imaging (fMRI) has established itself as the main research tool in neuroscience and brain cognitive research. The common marmoset (Callithrix jacchus) is a non-human primate model of increasing interest in biomedical research. However, commercial MRI coils for marmosets are not generally available. The present work describes the design and construction of a 4-channel receive-only surface RF coil array with excellent signal-to-noise ratio (SNR) specifically optimized for fMRI experiments in awake marmosets in response to somatosensory stimulation. The array was designed as part of a helmet-based head restraint system used to prevent motion during the scans. High SNR was obtained by building the coil array using a thin and flexible substrate glued to the inner surface of the restraint helmet, so as to minimize the distance between the array elements and the somatosensory cortex. Decoupling between coil elements was achieved by partial geometrical overlapping and by connecting them to home-built low input impedance preamplifiers. In vivo images show excellent coverage of the brain cortical surface with high sensitivity near the somatosensory cortex. Embedding the coil elements within the restraint helmet allowed fMRI data in response to somatosensory stimulation to be collected with high sensitivity and reproducibility in conscious, awake marmosets. PMID:23696219

  17. E2F mediates induction of the Sp1-controlled promoter of the human DNA polymerase ɛ B-subunit gene POLE2

    PubMed Central

    Huang, Deqi; Jokela, Maarit; Tuusa, Jussi; Skog, Sven; Poikonen, Kari; Syväoja, Juhani E.

    2001-01-01

    The B-subunits of replicative DNA polymerases from Archaea to humans belong to the same protein family, suggesting that they share a common fundamental function. We report here the gene structure for the B-subunit of human DNA polymerase ɛ (POLE2), whose expression and transcriptional regulation is typical for replication proteins with some unique features. The 75 bp core promoter region, located within exon 1, contains an Sp1 element that is a critical determinant of promoter activity as shown by the luciferase reporter, electrophoretic mobility shift and DNase I footprinting assays. Two overlapping E2F elements adjacent to the Sp1 element are essential for full promoter activity and serum response. Binding sites for E2F1 and NF-1 reside immediately downstream from the core promoter region. Our results suggest that human POLE2 is regulated by two E2F–pocket protein complexes, one associated with Sp1 and the other with NF-1. So far, only one replicative DNA polymerase B-subunit gene promoter, POLA2 encoding the B-subunit of DNA polymerase α, has been characterized. Mitogenic activation of the POLE2 promoter by an E2F-mediated mechanism resembles that of POLA2, but the regulation of basal promoter activity is different between these two genes. PMID:11433027

  18. Determining the Oxygen Fugacity of Lunar Pyroclastic Glasses Using Vanadium Valence - An Update

    NASA Technical Reports Server (NTRS)

    Karner, J. M.; Sutton, S. R.; Papike, J. J.; Shearer, C. K.; Jones, J. H.; Newville, M.

    2004-01-01

    We have been developing an oxygen barometer based on the valence state of V (V(2+), V(3+), V(4+), and V(5+)) in solar system basaltic glasses. The V valence is determined by synchrotron micro x-ray absorption near edge structure (XANES), which uses x-ray absorption associated with core-electronic transitions (absorption edges) to reveal a pre-edge peak whose intensity is directly proportional to the valence state of an element. XANES has advantages over other techniques that determine elemental valence because measurements can be made non-destructively in air and in situ on conventional thin sections at a micrometer spatial resolution with elemental sensitivities of approx. 100 ppm. Recent results show that fO2 values derived from the V valence technique are consistent with fO2 estimates determined by other techniques for materials that crystallized above the IW buffer. The fO2's determined by V valence (IW-3.8 to IW-2) for the lunar pyroclastic glasses, however, are on the order of 1 to 2.8 log units below previous estimates. Furthermore, the calculated fO2's decrease with increasing TiO2 contents from the A17 VLT to the A17 Orange glasses. In order to investigate these results further, we have synthesized lunar green and orange glasses and examined them by XANES.

  19. Redox state of recycled crustal lithologies in the convective upper mantle constrained using oceanic basalt CO2-trace element systematics

    NASA Astrophysics Data System (ADS)

    Eguchi, J.; Dasgupta, R.

    2017-12-01

    Investigating the redox state of the convective upper mantle remains challenging as there is no way of retrieving samples from this part of the planet. Current views of mantle redox are based on Fe3+/∑Fe of minerals in mantle xenoliths and thermodynamic calculations of fO2 [1]. However, deep xenoliths are only recoverable from continental lithospheric mantle, which may have different fO2s than the convective oceanic upper mantle [1]. To gain insight on the fO2 of the deep parts of the oceanic upper mantle, we probe CO2-trace element systematics of basalts that have been argued to receive contributions from subducted crustal lithologies that typically melt deeper than peridotite. Because CO2 contents of silicate melts at graphite saturation vary with fO2 [2], we suggest CO2-trace element systematics of oceanic basalts which sample deep heterogeneities may provide clues about the fO2 of the convecting mantle containing embedded heterogeneities. We developed a new model to predict CO2 contents in nominally anhydrous silicate melts from graphite- to fluid-saturation over a range of P (0.05- 5 GPa), T (950-1600 °C), and composition (foidite-rhyolite). We use the model to calculate CO2 content as a function of fO2 for partial melts of lithologies that vary in composition from rhyolitic sediment melt to silica-poor basaltic melt of pyroxenites. We then use modeled CO2 contents in mixing calculations with partial melts of depleted mantle to constrain the fO2 required for partial melts of heterogeneities to deliver sufficient CO2 to explain CO2-trace element systematics of natural basalts. As an example, Pitcairn basalts, which show evidence of a subducted crustal component [3] require mixing of 40% of partial melts of a garnet pyroxenite at ΔFMQ -1.75 at 3 GPa. Mixing with a more silicic composition such as partial melts of a MORB-eclogite cannot deliver enough CO2 at graphite saturation, so in this scenario fO2 must be above the EMOG/D buffer at 4 GPa. Results suggest convecting upper mantle may be more oxidized than continental lithospheric mantle, and fO2 profiles of continental lithospheric mantle may not be applicable to convective upper mantle.[1] Frost, D, McCammon, C. 2008. An Rev E & P Sci. (36) p.389-420; [2] Holloway, J, et al. 1992. Eu J. Min. (4) p. 105-114; [3] Woodhead, J, Devey C. 1993. EPSL. (116) p. 81-99.

  20. Metastable Se6 as a ligand for Ag+: from isolated molecular to polymeric 1D and 2D structures.

    PubMed

    Aris, Damian; Beck, Johannes; Decken, Andreas; Dionne, Isabelle; Schmedt auf der Günne, Jörn; Hoffbauer, Wilfried; Köchner, Tobias; Krossing, Ingo; Passmore, Jack; Rivard, Eric; Steden, Folker; Wang, Xinping

    2011-06-14

    Attempts to prepare the hitherto unknown Se(6)(2+) cation by the reaction of elemental selenium and Ag[A] ([A](-) = [Sb(OTeF(5))(6)](-), [Al(OC(CF(3))(3))(4)](-)) in SO(2) led to the formation of [(OSO)Ag(Se(6))Ag(OSO)][Sb(OTeF(5))(6)](2)1 and [(OSO)(2)Ag(Se(6))Ag(OSO)(2)][Al(OC(CF(3))(3))(4)](2)2a. 1 could only be prepared by using bromine as co-oxidant, however, bulk 2b (2a with loss of SO(2)) was accessible from Ag[Al(OC(CF(3))(3))(4)] and grey Se in SO(2) (chem. analysis). The reactions of Ag[MF(6)] (M = As, Sb) and elemental selenium led to crystals of 1/∞{[Ag(Se(6))](∞)[Ag(2)(SbF(6))(3)](∞)} 3 and {1/∞[Ag(Se(6))Ag](∞)}[AsF(6)](2)4. Pure bulk 4 was best prepared by the reaction of Se(4)[AsF(6)](2), silver metal and elemental selenium. Attempts to prepare bulk 1 and 3 were unsuccessful. 1-4 were characterized by single-crystal X-ray structure determinations, 2b and 4 additionally by chemical analysis and 4 also by X-ray powder diffraction, FT-Raman and FT-IR spectroscopy. Application of the PRESTO III sequence allowed for the first time (109)Ag MAS NMR investigations of 4 as well as AgF, AgF(2), AgMF(6) and {1/∞[Ag(I(2))](∞)}[MF(6)] (M = As, Sb). Compounds 1 and 2a/b, with the very large counter ions, contain isolated [Ag(Se(6))Ag](2+) heterocubane units consisting of a Se(6) molecule bicapped by two silver cations (local D(3d) sym). 3 and 4, with the smaller anions, contain close packed stacked arrays of Se(6) rings with Ag(+) residing in octahedral holes. Each Ag(+) ion coordinates to three selenium atoms of each adjacent Se(6) ring. 4 contains [Ag(Se(6))(+)](∞) stacks additionally linked by Ag(2)(+) into a two dimensional network. 3 features a remarkable 3-dimensional [Ag(2)(SbF(6))(3)](-) anion held together by strong Sb-FAg contacts between the component Ag(+) and [SbF(6)](-) ions. The hexagonal channels formed by the [Ag(2)(SbF(6))(3)](-) anions are filled by stacks of [Ag(Se(6))(+)](∞) cations. Overall 1-4 are new members of the rare class of metal complexes of neutral main group elemental clusters, in which the main group element is positively polarized due to coordination to a metal ion. Notably, 1 to 4 include the commonly metastable Se(6) molecule as a ligand. The structure, bonding and thermodynamics of 1 to 4 were investigated with the help of quantum chemical calculations (PBE0/TZVPP and (RI-)MP2/TZVPP, in part including COSMO solvation) and Born-Fajans-Haber-cycle calculations. From an analysis of all the available data it appears that the formation of the usually metastable Se(6) molecule from grey selenium is thermodynamically driven by the coordination to the Ag(+) ions.

  1. A saxitoxin-binding aptamer with higher affinity and inhibitory activity optimized by rational site-directed mutagenesis and truncation.

    PubMed

    Zheng, X; Hu, B; Gao, S X; Liu, D J; Sun, M J; Jiao, B H; Wang, L H

    2015-07-01

    Saxitoxin (STX), a member of the family of paralytic shellfish poisoning toxins, poses toxicological and ecotoxicological risks. To develop an analytical recognition element for STX, a DNA aptamer (APT(STX1)) was previously discovered via an iterative process known as Systematic Evolution of Ligands by Exponential Enrichment (SELEX) by Handy et al. Our study focused on generating an improved aptamer based on APT(STX1) through rational site-directed mutation and truncation. In this study, we generated the aptamer, M-30f, with a 30-fold higher affinity for STX compared with APT(STX1). The Kd value for M-30f was 133 nM, which was calculated by Bio-Layer Interferometry. After optimization, we detected and compared the interaction of STX with aptamers (APT(STX1) or M-30f) through several techniques (ELISA, cell bioassay, and mouse bioassay). Both aptamers' STX-binding ability was demonstrated in all three methods. Moreover, M-30f performs better than its parent sequence with higher suppressive activity against STX. As a molecular recognition element, M-30f has good prospects for practical application. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Role of relativity in high-pressure phase transitions of thallium.

    PubMed

    Kotmool, Komsilp; Chakraborty, Sudip; Bovornratanaraks, Thiti; Ahuja, Rajeev

    2017-02-20

    We demonstrate the relativistic effects in high-pressure phase transitions of heavy element thallium. The known first phase transition from h.c.p. to f.c.c. is initially investigated by various relativistic levels and exchange-correlation functionals as implemented in FPLO method, as well as scalar relativistic scheme within PAW formalism. The electronic structure calculations are interpreted from the perspective of energetic stability and electronic density of states. The full relativistic scheme (FR) within L(S)DA performs to be the scheme that resembles mostly with experimental results with a transition pressure of 3 GPa. The s-p hybridization and the valence-core overlapping of 6s and 5d states are the primary reasons behind the f.c.c. phase occurrence. A recent proposed phase, i.e., a body-centered tetragonal (b.c.t.) phase, is confirmed with a small distortion from the f.c.c. phase. We have also predicted a reversible b.c.t. → f.c.c. phase transition at 800 GPa. This finding has been suggested that almost all the III-A elements (Ga, In and Tl) exhibit the b.c.t. → f.c.c. phase transition at extremely high pressure.

  3. Synthesis and characterization of Heck-cross coupling 4-(4-nitrostyryl) aniline as potential precursor in Schiff-base synthesis

    NASA Astrophysics Data System (ADS)

    Hassan, Norhafiefa; Izwani, Fatin; Yusoff, H. M.

    2017-09-01

    This is a preliminary study of alkoxy substituted Heck-schiff base compound as recognition layer in electrochemical DNA sensor for liver cancer. 4-(4-nitrostyryl)aniline was synthesized by bis (triphenylphosphine) palladium (II) dichloride as catalyst and has been characterized by using Fourier transform-infrared spectrometer (FTIR), UV-Vis spectrophotometer and Nuclear Magnetic Resonance (NMR) spectra. The result obtained from FTIR show that there are formation of N=O (NO2) asymmetric stretching vibrations 1340 cm-1. In UV-vis, absorbance of NO2 can be observed at peak 410 nm. While in the 1H NMR and 13C NMR the peak of C-C coupling was found in the range of δH 6.84-7.09 ppm and δC 125.23 ppm.

  4. Using titanium complexes to defeat cancer: the view from the shoulders of titans.

    PubMed

    Cini, Melchior; Bradshaw, Tracey D; Woodward, Simon

    2017-02-20

    When the first titanium complex with anticancer activity was identified in the 1970s, it was attractive, based on the presence of the dichloride unit in TiCl 2 Cp 2 (Cp = η-C 5 H 5 ) 2 , to assume its mode of biological action was closely aligned with cisplatin [cis-PtCl 2 (NH 3 ) 2 ]. Over the intervening 40 years however a far more complicated picture has arisen indicating multiple cellular mechanisms of cellular action can be triggered by titanium anti-cancer agents. This tutorial review aims to unpick the historical data and provide new researchers, without an explicit cancer biology background, a contemporary interpretation of both older and newer literature and to review the best techniques for attaining the identities of the biologically active titanium species and how these interact with the cancer cellular machinery.

  5. A simple high performance liquid chromatography method for analyzing paraquat in soil solution samples.

    PubMed

    Ouyang, Ying; Mansell, Robert S; Nkedi-Kizza, Peter

    2004-01-01

    A high performance liquid chromatography (HPLC) method with UV detection was developed to analyze paraquat (1,1'-dimethyl-4,4'-dipyridinium dichloride) herbicide content in soil solution samples. The analytical method was compared with the liquid scintillation counting (LSC) method using 14C-paraquat. Agreement obtained between the two methods was reasonable. However, the detection limit for paraquat analysis was 0.5 mg L(-1) by the HPLC method and 0.05 mg L(-1) by the LSC method. The LSC method was, therefore, 10 times more precise than the HPLC method for solution concentrations less than 1 mg L(-1). In spite of the high detection limit, the UC (nonradioactive) HPLC method provides an inexpensive and environmentally safe means for determining paraquat concentration in soil solution compared with the 14C-LSC method.

  6. FUEL ELEMENTS FOR THERMAL-FISSION NUCLEAR REACTORS

    DOEpatents

    Flint, O.

    1961-01-10

    Fuel elements for thermal-fission nuclear reactors are described. The fuel element is comprised of a core of alumina, a film of a metal of the class consisting of copper, silver, and nickel on the outer face of the core, and a coating of an oxide of a metal isotope of the class consisting of Un/sup 235/, U/ sup 233/, and Pu/sup 239/ on the metal f ilm.

  7. Sulfurospirillum arcachonense sp. nov., a new microaerophilic sulfur-reducing bacterium.

    PubMed

    Finster, K; Liesack, W; Tindall, B J

    1997-10-01

    The isolation of a new motile, gram-negative, heterotrophic, sulfur-reducing, microaerophilic, vibrioid bacterium, strain F1F6, from oxidized marine surface sediment (Arcachon Bay, French Atlantic coast) is described. Hydrogen (with acetate as the carbon source), formate (with acetate as the carbon source), pyruvate, lactate, alpha-ketoglutarate, glutarate, glutamate, and yeast extract supported growth with elemental sulfur under anaerobic conditions. Apart from H2 and formate, the oxidation of the substrates was incomplete. Microaerophilic growth was supported with hydrogen (acetate as the carbon source), formate (acetate as the carbon source), acetate, propionate, pyruvate, lactate, alpha-ketoglutarate, glutamate, yeast extract, fumarate, succinate, malate, citrate, and alanine. The isolate grew fermentatively with fumarate, succinate being the only organic product. Elemental sulfur and oxygen were the only electron acceptors used. Vitamins or amino acids were not required. The isolate was oxidase, catalase, and urease positive. Comparative 16S rDNA sequence analysis revealed a tight cluster consisting of the validly described species Sulfurospirillum deleyianum and the strains SES-3 and CCUG 13942 as the closest relatives of strain F1F6 (level of sequence similarity, 91.7 to 92.4%). Together with strain F1F6, these organisms form a novel lineage within the epsilon subclass of proteobacteria clearly separated from the described species of the genera Arcobacter, Campylobacter, Wolinella, and Helicobacter. Due to the phenotypic characteristics shared by strain F1F6 and S. deleyianum and considering their phylogenetic relationship, we propose the inclusion of strain F1F6 in the genus Sulfurospirillum, namely, as S. arcachonense sp. nov. Based on the results of this study, an emended description of the genus Sulfurospirillum is given.

  8. Emotion Regulation Training for Treating Warfighters with Combat-Related PTSD Using Real-Time fMRI and EEG-Assisted Neurofeedback

    DTIC Science & Technology

    2015-10-01

    AWARD NUMBER: W81XWH-12-1-0607 TITLE: "Emotion Regulation Training for Treating Warfighters with Combat-Related PTSD Using Real-Time fMRI and...Related PTSD Using Real-Time fMRI and EEG-Assisted Neurofeedback" 5a. CONTRACT NUMBER W81XWH-12-1-0607 5b. GRANT NUMBER PT110256 5c. PROGRAM ELEMENT...neurofeedback training protocol to evaluate FEA EEG-nf training feasibility in combat-related PTSD. 15. SUBJECT TERMS PTSD; amygdala; fMRI ; EEG

  9. The Effects of the Uncertainty of Thermodynamic and Kinetic Properties on Nucleation and Evolution Kinetics of Cr-Rich Phase in Fe-Cr Alloys

    DTIC Science & Technology

    2012-12-01

    M. A.; Horstemeyer, M. F.; Gao, F.; Sun, X.: Khaleel, M. Scripta Materialia. 2011, 64, 908. 80. Plimpton , S . Journal of Computational Physics...99 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) Mark Tschopp,* Fei Gao,** and Xin Sun** 5d. PROJECT NUMBER 5e. TASK NUMBER...5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) U.S. Army Research Laboratory ATTN: RDRL-WMM-F Aberdeen Proving Ground

  10. (Compactified) black branes in four dimensional f(R)-gravity

    NASA Astrophysics Data System (ADS)

    Dimakis, N.; Giacomini, Alex; Paliathanasis, Andronikos

    2018-02-01

    A new family of analytical solutions in a four dimensional static spacetime is presented for f (R) -gravity. In contrast to General Relativity, we find that a non trivial black brane/string solution is supported in vacuum power law f (R) -gravity for appropriate values of the parameters characterizing the model and when axisymmetry is introduced in the line element. For the aforementioned solution, we perform a brief investigation over its basic thermodynamic quantities.

  11. RAF and Intelligence Warfighting Function

    DTIC Science & Technology

    2015-02-01

    Warfighting Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT...meet the CCDR’s need to leverage the entire Intelligence Enterprise. Balancing IWfF RAF “solutions against an ever reducing budget will require...right balance is important. Using DOTMLPF as a framework can assist in seeing how the IWfF can support RAF implementation. Furthermore, identifying gaps

  12. Oxidation characteristics of MgF2 in air at high temperature

    NASA Astrophysics Data System (ADS)

    Chen, H. K.; Jie, Y. Y.; Chang, L.

    2017-02-01

    High temperature oxidation properties of MgF2 in air were studied. The changes of phase composition, macro surface morphology, weight and elemental composition of MgF2 samples with temperature were investigated by using XRD, EDS and gravimetric analyses. The results show that the oxidation reaction of MgF2 converted to MgO occurred at high temperature, and the reaction was accelerated by the increase of temperature and the presence of impurities. This result clarifies the understanding of the high temperature oxidation behavior of MgF2 in air, and provides a theoretical basis for the reasonable application of MgF2 in optical coating materials, electronic ceramic materials and magnesium melt protection.

  13. Design and properties of silicon charged-particle detectors developed at the Institute of Electron Technology (ITE)

    NASA Astrophysics Data System (ADS)

    Wegrzecki, Maciej; Bar, Jan; Budzyński, Tadeusz; CieŻ, Michal; Grabiec, Piotr; Kozłowski, Roman; Kulawik, Jan; Panas, Andrzej; Sarnecki, Jerzy; Słysz, Wojciech; Szmigiel, Dariusz; Wegrzecka, Iwona; Wielunski, Marek; Witek, Krzysztof; Yakushev, Alexander; Zaborowski, Michał

    2013-07-01

    The paper discusses the design of charged-particle detectors commissioned and developed at the Institute of Electron Technology (ITE) in collaboration with foreign partners, used in international research on transactinide elements and to build personal radiation protection devices in Germany. Properties of these detectors and the results obtained using the devices are also presented. The design of the following epiplanar detector structures is discussed: ♢ 64-element chromatographic arrays for the COMPACT (Cryo On-line Multidetector for Physics And Chemistry of Transactinides) detection system used at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt (GSI) for research on Hassium, Copernicium and Flerovium, as well as elements 119 and 120, ♢ 2-element flow detectors for the COLD (Cryo On-Line Detector) system used for research on Copernicium and Flerovium at the Joint Institute for Nuclear Research, Dubna, ♢ detectors for a radon exposimeter and sensors for a neutron dosimeter developed at the Institut für Strahlenschutz, Helmholtz Zentrum München. The design of planar detectors - single-sided and double-sided strip detectors for the Focal Plane Detector Box used at GSI for research on Flerovium and elements 119 and 120 is also discussed.

  14. On spectral synthesis on element-wise compact Abelian groups

    NASA Astrophysics Data System (ADS)

    Platonov, S. S.

    2015-08-01

    Let G be an arbitrary locally compact Abelian group and let C(G) be the space of all continuous complex-valued functions on G. A closed linear subspace \\mathscr H\\subseteq C(G) is referred to as an invariant subspace if it is invariant with respect to the shifts τ_y\\colon f(x)\\mapsto f(xy), y\\in G. By definition, an invariant subspace \\mathscr H\\subseteq C(G) admits strict spectral synthesis if \\mathscr H coincides with the closure in C(G) of the linear span of all characters of G belonging to \\mathscr H. We say that strict spectral synthesis holds in the space C(G) on G if every invariant subspace \\mathscr H\\subseteq C(G) admits strict spectral synthesis. An element x of a topological group G is said to be compact if x is contained in some compact subgroup of G. A group G is said to be element-wise compact if all elements of G are compact. The main result of the paper is the proof of the fact that strict spectral synthesis holds in C(G) for a locally compact Abelian group G if and only if G is element-wise compact. Bibliography: 14 titles.

  15. Volatile element chemistry in the solar nebula - Na, K, F, Cl, Br, and P

    NASA Technical Reports Server (NTRS)

    Fegley, B., Jr.; Lewis, J. S.

    1980-01-01

    The results of the most extensive set to date of thermodynamic calculations on the equilibrium chemistry of several hundred compounds of the elements Na, K, F, Cl, Br, and P in a solar composition system are reported. Two extreme models of accretion are investigated. In one extreme complete chemical equilibrium between condensates and gases is maintained because the time scale for accretion is long compared to the time scale for cooling or dissipation of the nebula. Condensates formed in this homogeneous accretion model include several phases such as whitlockite, alkali feldspars, and apatite minerals which are found in chondrites. In the other extreme complete isolation of newly formed condensates from prior condensates and gases occurs due to a time scale for accretion that is short relative to the time required for nebular cooling or dissipation. The condensates produced in this heterogeneous accretion model include alkali sulfides, ammonium halides, and ammonium phosphates. None of these phases are found in chondrites. Available observations of the Na, K, F, Cl, Br, and P elemental abundances in the terrestrial planets are found to be compatible with the predictions of the homogeneous accretion model.

  16. Ultrasoft pseudopotentials and Hubbard U values for rare-earth elements (Re=La-Lu) guided by HSE06 calculations

    NASA Astrophysics Data System (ADS)

    Topsakal, Mehmet; Umemoto, Koichiro; Wentzcovitch, Renata

    2014-03-01

    The lanthanide series of the periodic table comprises fifteen members ranging from La to Lu - the rare-earth (Re) elements. They exhibit unique (and mostly unexplored) chemical properties depending on the fillings of 4f-orbitals. Due to strong electronic correlation, 4f valence electrons are incorrectly described by standard DFT functionals. In order to cope with these inefficiencies, the DFT+U method is often employed where Hubbard-type U is introduced into the standard DFT. Another approach is to use hybrid functionals. Both improve the treatment of strongly correlated electrons. However, DFT+U suffers from ambiguity of U while hybrid functionals suffer from extremely demanding computational costs. Here we provide Vanderbilt type ultrasoft pseudopotentials for Re elements with suggested U values allowing efficient plane-wave calculations. Hubbard U values are determined according to HSE06 calculations on Re-nitrides (ReN). Generated pseudopotentials were further tested on some Re-cobaltite (Re-CoO3) perovskites. Alternative pseudopotentials with f-electrons kept frozen in the core of pseudopotential are also provided and possible outcomes are addressed. We believe that these new pseudopotentials with suggested U values will allow further studies on rare-earth materials.

  17. Chemical bonds and vibrational properties of ordered (U, Np, Pu) mixed oxides

    NASA Astrophysics Data System (ADS)

    Yang, Yu; Zhang, Ping

    2013-01-01

    We use density functional theory +U to investigate the chemical bonding characters and vibrational properties of the ordered (U, Np, Pu) mixed oxides (MOXs), UNpO4,NpPuO4, and UPuO4. It is found that the 5f electronic states of different actinide elements keep their localized characters in all three MOXs. The occupied 5f electronic states of different actinide elements do not overlap with each other and tend to distribute over the energy band gap of the other actinide element's 5f states. As a result, the three ordered MOXs all show smaller band gaps than those of the component dioxides, with values of 0.91, 1.47, and 0.19 eV for UNpO4,NpPuO4, and UPuO4, respectively. Through careful charge density analysis, we further show that the U-O and Pu-O bonds in MOXs show more ionic character than in UO2 and PuO2, while the Np-O bonds show more covalent character than in NpO2. The change in covalencies in the chemical bonds leads to vibrational frequencies of oxygen atoms that are different in MOXs.

  18. The role of hydrothermal processes in concentrating high-field strength elements in the Strange Lake peralkaline complex, northeastern Canada

    NASA Astrophysics Data System (ADS)

    Salvi, Stefano; Williams-Jones, Anthony E.

    1996-06-01

    The middle-Proterozoic peralkaline pluton at Strange Lake, Quebec/Labrador, comprises hypersolvus to subsolvus phases which are unusually enriched in Zr, Y, REEs, Nb, Be, and F, as exotic alkali and alkaline-earth silicate minerals. The highest concentrations of these elements are in subsolvus granite, which underwent intense low temperature (≤200°C) hydrothermal alteration involving hematization and the replacement of alkali high-field strength element (HFSE) minerals by calcic equivalents. This alteration is interpreted to have been caused by meteoric or formational waters. High temperature (≥ 350°C) alteration, attributed to orthomagmatic fluids, is evident in other parts of the subsolvus granite by the replacement of arfvedsonite by aegirine. Comparisons of the chemical compositions of fresh and altered rocks indicate that rocks subjected to high temperature alteration were chemically unaffected, except for depletion in Zr, Y, and HREEs. These elements were appreciably enriched in rocks that underwent low temperature alteration. Other elements affected by low temperature alteration include Ca and Mg, which were added and Na, which was removed. Available data on HFSE speciation in aqueous fluids and the chemistry of the pluton, suggest that the HFSEs were transported as fluoride complexes. If this was the case, the low temperature fluid could not have been responsible for HFSE transport, because the high concentration of Ca and low solubility of fluorite would have buffered F - activity to levels too low to permit significant complexation. We propose that HFSE mineralization and accompanying alteration were the result of mixing, in the apical parts of the pluton, of a F-rich, essentially Ca-free orthomagmatic fluid containing significant concentrations of HFSEs, with an externally derived meteoric-dominated fluid, enriched in Ca as a result of interaction with calc-silicate gneisses and gabbros. According to this interpretation, the latter fluid was responsible for the exchange of Ca for alkalis, mainly Na, in HFSE-rich minerals and, by sharply reducing F - activity in the mixed fluid through fluorite precipitation and/or increasing pH, destabilised the HFSE-fluoride complexes, causing deposition of HFSE-bearing minerals. An important implication of this study is that major HFSE enrichment may be restricted to those rare cases where F-rich, Ca-free, metal leaching environments and Ca-rich depositional environments are juxtaposed.

  19. Bivariate- distribution for transition matrix elements in Breit-Wigner to Gaussian domains of interacting particle systems.

    PubMed

    Kota, V K B; Chavda, N D; Sahu, R

    2006-04-01

    Interacting many-particle systems with a mean-field one-body part plus a chaos generating random two-body interaction having strength lambda exhibit Poisson to Gaussian orthogonal ensemble and Breit-Wigner (BW) to Gaussian transitions in level fluctuations and strength functions with transition points marked by lambda = lambda c and lambda = lambda F, respectively; lambda F > lambda c. For these systems a theory for the matrix elements of one-body transition operators is available, as valid in the Gaussian domain, with lambda > lambda F, in terms of orbital occupation numbers, level densities, and an integral involving a bivariate Gaussian in the initial and final energies. Here we show that, using a bivariate-t distribution, the theory extends below from the Gaussian regime to the BW regime up to lambda = lambda c. This is well tested in numerical calculations for 6 spinless fermions in 12 single-particle states.

  20. EVA space suit Evaporative Cooling/Heating Glove System (ECHGS)

    NASA Technical Reports Server (NTRS)

    Coss, F. A.

    1976-01-01

    A new astronaut glove, the Evaporative Cooling/Heating Glove System (ECHGS), was designed and developed to allow the handling of objects between -200 F and +200 F. Active heating elements, positioned at each finger pad, provide additional heat to the finger pads from the rest of the finger. A water evaporative cooling system provides cooling by the injection of water to the finger areas and the subsequent direct evaporation to space. Thin, flexible insulation has been developed for the finger areas to limit thermal conductivity. Component and full glove tests have shown that the glove meets and exceeds the requirements to hold a 11/2 inch diameter bar at + or - 200 F for three minutes within comfort limits. The ECHGS is flexible, lightweight and comfortable. Tactility is reasonable and small objects can be identified especially by the fingertips beyond the one half width active elements.

  1. Influence of Young's moduli in 3D fluid-structure coupled models of the human cochlea

    NASA Astrophysics Data System (ADS)

    Böhnke, Frank; Semmelbauer, Sebastian; Marquardt, Torsten

    2015-12-01

    The acoustic wave propagation in the human cochlea was studied using a tapered box-model with linear assumptions respective to all mechanical parameters. The discretisation and evaluation is conducted by a commercial finite element package (ANSYS). The main difference to former models of the cochlea was the representation of the basilar membrane by a 3D elastic solid. The Young's moduli of this solid were modified to study their influence on the travelling wave. The lymph in the scala vestibuli and scala tympani was represented by a viscous and nearly incompressible fluid finite element approach. Our results show the maximum displacement for f = 2kHz at half of the length of the cochlea in accordance with former experiments. For low frequencies f <200 Hz nearly zero phase shifts were found, whereas for f =1 kHz it reaches values up to -12 cycles depending on the degree of orthotropy.

  2. Photoacoustic Imaging of Epilepsy

    DTIC Science & Technology

    2012-04-01

    fBg ; ð4Þ where the elements of matrix ½K , ½C, and ½M are Kij ¼ Z S ∇ψ i ·∇ψ jdSþ 1 2r I l ψ iψ jdl; Cij ¼ 1 v0 I l ψ iψ jdl; Mij ¼ 1 v20 Z S ψ iψ...jdS; and the column vectors fpg, f _pg, f€pg, and fBg are Bi ¼ β Cp Z S ψ i X k ψkΦk dS · ∂J ∂t fpg ¼ fp1; p2; pNgT ; f _pg ¼ f _p1; _p2

  3. Calibration of 3D ALE finite element model from experiments on friction stir welding of lap joints

    NASA Astrophysics Data System (ADS)

    Fourment, Lionel; Gastebois, Sabrina; Dubourg, Laurent

    2016-10-01

    In order to support the design of such a complex process like Friction Stir Welding (FSW) for the aeronautic industry, numerical simulation software requires (1) developing an efficient and accurate Finite Element (F.E.) formulation that allows predicting welding defects, (2) properly modeling the thermo-mechanical complexity of the FSW process and (3) calibrating the F.E. model from accurate measurements from FSW experiments. This work uses a parallel ALE formulation developed in the Forge® F.E. code to model the different possible defects (flashes and worm holes), while pin and shoulder threads are modeled by a new friction law at the tool / material interface. FSW experiments require using a complex tool with scroll on shoulder, which is instrumented for providing sensitive thermal data close to the joint. Calibration of unknown material thermal coefficients, constitutive equations parameters and friction model from measured forces, torques and temperatures is carried out using two F.E. models, Eulerian and ALE, to reach a satisfactory agreement assessed by the proper sensitivity of the simulation to process parameters.

  4. HBS1L-MYB intergenic variants modulate fetal hemoglobin via long-range MYB enhancers

    PubMed Central

    Stadhouders, Ralph; Aktuna, Suleyman; Thongjuea, Supat; Aghajanirefah, Ali; Pourfarzad, Farzin; van IJcken, Wilfred; Lenhard, Boris; Rooks, Helen; Best, Steve; Menzel, Stephan; Grosveld, Frank; Thein, Swee Lay; Soler, Eric

    2014-01-01

    Genetic studies have identified common variants within the intergenic region (HBS1L-MYB) between GTP-binding elongation factor HBS1L and myeloblastosis oncogene MYB on chromosome 6q that are associated with elevated fetal hemoglobin (HbF) levels and alterations of other clinically important human erythroid traits. It is unclear how these noncoding sequence variants affect multiple erythrocyte characteristics. Here, we determined that several HBS1L-MYB intergenic variants affect regulatory elements that are occupied by key erythroid transcription factors within this region. These elements interact with MYB, a critical regulator of erythroid development and HbF levels. We found that several HBS1L-MYB intergenic variants reduce transcription factor binding, affecting long-range interactions with MYB and MYB expression levels. These data provide a functional explanation for the genetic association of HBS1L-MYB intergenic polymorphisms with human erythroid traits and HbF levels. Our results further designate MYB as a target for therapeutic induction of HbF to ameliorate sickle cell and β-thalassemia disease severity. PMID:24614105

  5. Mechanical Pre-Stressing a Transducer through a Negative DC Biasing Field

    DTIC Science & Technology

    2017-04-21

    13  ii LIST OF ABBREVIATIONS AND ACRONYMS AC Alternating Current DC Direct Currant FEA Finite Element Analysis NUWC Naval...at resonance into tension is shown in figure 3; it was estimated from finite element analysis (FEA) that the tensional stresses exceeded 2000 psi...PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Stephen C. Butler 5.d PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION

  6. Recent Progress in the p and h-p Version of the Finite Element Method.

    DTIC Science & Technology

    1987-07-01

    code PROBE which was developed recently by NOETIC Technologies, St. Louis £54]. PROBE solves two dimensional problems of linear elasticity, stationary...of the finite element method was studied in detail from various point of view. We will mention here some essential illustrative results. In one...28) Bathe, K. J., Brezzi, F., Studies of finite element procedures - the INF-SUP condition, equivalent forms and applications in Reliability of

  7. Compositionally Controlled Volatile Content of Nominally Volatile-Free Minerals in the Continental Upper Mantle of Southern Gondwana (Patagonia & W. Antarctica)

    NASA Astrophysics Data System (ADS)

    Rooks, E. E.; Gibson, S. A.; Leat, P. T.; Petrone, C. M.

    2015-12-01

    H2O and F contents affect many physical and chemical properties of the upper mantle, including melting temperature and viscosity. These elements are hosted by hydrous and F-rich phases, and by modally abundant, nominally-anhydrous/halogen-free mantle minerals, which can potentially accommodate the entire volatile budget of the upper mantle. We present high-precision SIMS analyses of H2O, and F in mantle xenoliths hosted by recently-erupted (5-10 Ka) alkali basalts from south Patagonia (Pali Aike) and older (c. 25 Ma) alkali basalts from localities along the Antarctic Peninsula. Samples are well characterised peridotites and pyroxenites, from a range of depths in the off-craton lithospheric mantle. Minerals are relatively dry: H2O contents of olivine span 0-49 ppm, orthopyroxene 150-235 ppm and clinopyroxene 100-395 ppm, with highest concentrations found in spinel-garnet lherzolites from Pali Aike. These H2O concentrations fall within the global measured range for off-craton mantle minerals. H2O and F are correlated, and the relative compatibility of F in mantle phases is clinopyroxene>orthopyroxene>olivine. However, elevated F concentrations of 100-210 ppm are found in pyroxenites from two Antarctic localities. This elevated F content is not correlated with high H2O, suggesting that these rocks interacted with a F-rich melt. In clinopyroxenes, F concentration is correlated with Ti, and the ratio of M1Ti to M1Al + M1Cr, suggesting a charge balanced substitution. Consistency between samples (excepting high-F pyroxenites) suggests a constant F-budget, and that concentrations in clinopyroxenes are controlled by mineral chemistry. In orthopyroxene, F correlates with CaO, but no other major or minor elements. Large variability of H2O concentrations within samples is attributed to diffusive loss during ascent. Cl is negligible in all samples, indicating little or no influence of slab fluids from this long-lived subduction zone.

  8. A volatile topic: Parsing out the details of Earth's formation through experimental metal-silicate partitioning of volatile and moderately volatile elements

    NASA Astrophysics Data System (ADS)

    Mahan, B. M.; Siebert, J.; Blanchard, I.; Badro, J.; Sossi, P.; Moynier, F.

    2017-12-01

    Volatile and moderately volatile elements display different volatilities and siderophilities, as well as varying sensitivity to thermodynamic controls (X, P, T, fO2) during metal-silicate differentiation. The experimental determination of the metal-silicate partitioning of these elements permits us to evaluate processes controlling the distribution of these elements in Earth. In this work, we have combined metal-silicate partitioning data and results for S, Sn, Zn and Cu, and input these characterizations into Earth formation models. Model parameters such as source material, timing of volatile delivery, fO2 path, and degree of impactor equilibration were varied to encompass an array of possible formation scenarios. These models were then assessed to discern plausible sets of conditions that can produce current observed element-to-element ratios (e.g. S/Zn) in the Earth's present-day mantle, while also satisfying current estimates on the S content of the core, at no more than 2 wt%. The results of our models indicate two modes of accretion that can maintain chondritic element-to-element ratios for the bulk Earth and can arrive at present-day mantle abundances of these elements. The first mode requires the late addition of Earth's entire inventory of these elements (assuming a CI-chondritic composition) and late-stage accretion that is marked by partial equilibration of large impactors. The second, possibly more intuitive mode, requires that Earth accreted - at least initially - from volatile poor material preferentially depleted in S relative to Sn, Zn, and Cu. From a chemical standpoint, this source material is most similar to type I chondrule rich (and S poor) materials (Hewins and Herzberg, 1996; Mahan et al., 2017; Amsellem et al., 2017), such as the metal-bearing carbonaceous chondrites.

  9. Traditional Versus Online Biology Courses: Connecting Course Design and Student Learning in an Online Setting

    PubMed Central

    Biel, Rachel; Brame, Cynthia J.

    2016-01-01

    Online courses are a large and growing part of the undergraduate education landscape, but many biology instructors are skeptical about the effectiveness of online instruction. We reviewed studies comparing the effectiveness of online and face-to-face (F2F) undergraduate biology courses. Five studies compared student performance in multiple course sections at community colleges, while eight were smaller scale and compared student performance in particular biology courses at a variety of types of institutions. Of the larger-scale studies, two found that students in F2F sections outperformed students in online sections, and three found no significant difference; it should be noted, however, that these studies reported little information about course design. Of the eight smaller scale studies, six found no significant difference in student performance between the F2F and online sections, while two found that the online sections outperformed the F2F sections. In alignment with general findings about online teaching and learning, these results suggest that well-designed online biology courses can be effective at promoting student learning. Three recommendations for effective online instruction in biology are given: the inclusion of an online orientation to acclimate students to the online classroom; student-instructor and student-student interactions facilitated through synchronous and asynchronous communication; and elements that prompt student reflection and self-assessment. We conclude that well-designed online biology courses can be as effective as their traditional counterparts, but that more research is needed to elucidate specific course elements and structures that can maximize online students’ learning of key biology skills and concepts. PMID:28101268

  10. Traditional Versus Online Biology Courses: Connecting Course Design and Student Learning in an Online Setting.

    PubMed

    Biel, Rachel; Brame, Cynthia J

    2016-12-01

    Online courses are a large and growing part of the undergraduate education landscape, but many biology instructors are skeptical about the effectiveness of online instruction. We reviewed studies comparing the effectiveness of online and face-to-face (F2F) undergraduate biology courses. Five studies compared student performance in multiple course sections at community colleges, while eight were smaller scale and compared student performance in particular biology courses at a variety of types of institutions. Of the larger-scale studies, two found that students in F2F sections outperformed students in online sections, and three found no significant difference; it should be noted, however, that these studies reported little information about course design. Of the eight smaller scale studies, six found no significant difference in student performance between the F2F and online sections, while two found that the online sections outperformed the F2F sections. In alignment with general findings about online teaching and learning, these results suggest that well-designed online biology courses can be effective at promoting student learning. Three recommendations for effective online instruction in biology are given: the inclusion of an online orientation to acclimate students to the online classroom; student-instructor and student-student interactions facilitated through synchronous and asynchronous communication; and elements that prompt student reflection and self-assessment. We conclude that well-designed online biology courses can be as effective as their traditional counterparts, but that more research is needed to elucidate specific course elements and structures that can maximize online students' learning of key biology skills and concepts.

  11. The effects of orientation and attention during surround suppression of small image features: A 7 Tesla fMRI study.

    PubMed

    Schallmo, Michael-Paul; Grant, Andrea N; Burton, Philip C; Olman, Cheryl A

    2016-08-01

    Although V1 responses are driven primarily by elements within a neuron's receptive field, which subtends about 1° visual angle in parafoveal regions, previous work has shown that localized fMRI responses to visual elements reflect not only local feature encoding but also long-range pattern attributes. However, separating the response to an image feature from the response to the surrounding stimulus and studying the interactions between these two responses demands both spatial precision and signal independence, which may be challenging to attain with fMRI. The present study used 7 Tesla fMRI with 1.2-mm resolution to measure the interactions between small sinusoidal grating patches (targets) at 3° eccentricity and surrounds of various sizes and orientations to test the conditions under which localized, context-dependent fMRI responses could be predicted from either psychophysical or electrophysiological data. Targets were presented at 8%, 16%, and 32% contrast while manipulating (a) spatial extent of parallel (strongly suppressive) or orthogonal (weakly suppressive) surrounds, (b) locus of attention, (c) stimulus onset asynchrony between target and surround, and (d) blocked versus event-related design. In all experiments, the V1 fMRI signal was lower when target stimuli were flanked by parallel versus orthogonal context. Attention amplified fMRI responses to all stimuli but did not show a selective effect on central target responses or a measurable effect on orientation-dependent surround suppression. Suppression of the V1 fMRI response by parallel surrounds was stronger than predicted from psychophysics but showed a better match to previous electrophysiological reports.

  12. A Version of the Graphics-Oriented Interactive Finite Element Time-Sharing System (GIFTS) for an IBM with CP/CMS.

    DTIC Science & Technology

    1982-03-01

    POSTGRADUATE SCHOOL fMonterey, California THESIS A VERSION OF THE GRAPHICS-ORIENTED INTERACTIVE FINITE ELEMENT TIME-SHARING SYSTEM ( GIFTS ) FOR AN IBM...Master’s & Engineer’s active Finite Element Time-sharing System Thesis - March 1982 ( GIFTS ) for an IBM with CP/CMS 6. penromm.oOn. REPoRT MUlmiR 1. AUTHOIee...ss0in D dinuf 5W M memisi) ’A version of the Graphics-oriented, Interactive, Finite element, Time-sharing System ( GIFTS ) has been developed for, and

  13. An Error Analysis for the Finite Element Method Applied to Convection Diffusion Problems.

    DTIC Science & Technology

    1981-03-01

    D TFhG-]NOLOGY k 4b 00 \\" ) ’b Technical Note BN-962 AN ERROR ANALYSIS FOR THE FINITE ELEMENT METHOD APPLIED TO CONVECTION DIFFUSION PROBLEM by I...Babu~ka and W. G. Szym’czak March 1981 V.. UNVI I Of- ’i -S AN ERROR ANALYSIS FOR THE FINITE ELEMENT METHOD P. - 0 w APPLIED TO CONVECTION DIFFUSION ...AOAO98 895 MARYLAND UNIVYCOLLEGE PARK INST FOR PHYSICAL SCIENCE--ETC F/G 12/I AN ERROR ANALYIS FOR THE FINITE ELEMENT METHOD APPLIED TO CONV..ETC (U

  14. Synthesis of Ti Oxides at Reducing Conditions: Implications for Beamline Standards and Cosmochemistry

    NASA Technical Reports Server (NTRS)

    Righter, K.; Pando, K. A.; Butterworth, A. L.; Gainsforth, Z.; Jilly-Rehak, C. E.; Westphal, A. J.

    2017-01-01

    These initial experiments demonstrate the great potential for synthesizing customized compounds for use as standards, or in buffering experiments at reducing conditions. We are also investigating Cr and V oxides, as well as compounds containing these elements such as FeV2O4 and FeCr2O4. Oxygen fugacity exerts a major control on mineral major element chemistry and elemental valence of minerals in any plane-tary compositional system [1]. For Earth, Fe is multivalent ranging from nearly Fe0 at low fO2 in the deep mantle to Fe2+ to Fe3+ at high low fO2. For solar nebular and meteoritic materials fO2 ranges from near IW to 10 log fO2 units below the IW buffer [1]. Phases in CAIs, for example, contain no Fe2+, but may contain Ti4+, Ti3+, or Ti2+, and Cr3+ or Cr2+, and V3+ or V2+ [1,2,3]. De-tailed study of inclusions may reveal important differences in fO2 thus reflecting different environments in the solar nebula [4]. XANES, FEG-SEM, and TEM can reveal such variations in micro and nano samples such as Stardust and cosmic dust particles [5], but successful application to reduced conditions depends upon the availability of well characterized standards. Acquiring appropriate standards for reduced phases that contain Ti3+ or Ti2+, Cr3+ or Cr2+, and V3+ or V2+ can be a challenge. Here we report our preliminary results at synthesizing reduced Ti bearing standards, and focus on the preliminary characterization.

  15. Alternation frequency thresholds for stereopsis as a technique for exploring stereoscopic difficulties

    PubMed Central

    Rychkova, Svetlana; Ninio, Jacques

    2011-01-01

    When stereoscopic images are presented alternately to the two eyes, stereopsis occurs at F ≥ 1 Hz full-cycle frequencies for very simple stimuli, and F ≥ 3 Hz full-cycle frequencies for random-dot stereograms (eg Ludwig I, Pieper W, Lachnit H, 2007 “Temporal integration of monocular images separated in time: stereopsis, stereoacuity, and binocular luster” Perception & Psychophysics 69 92–102). Using twenty different stereograms presented through liquid crystal shutters, we studied the transition to stereopsis with fifteen subjects. The onset of stereopsis was observed during a stepwise increase of the alternation frequency, and its disappearance was observed during a stepwise decrease in frequency. The lowest F values (around 2.5 Hz) were observed with stimuli involving two to four simple disjoint elements (circles, arcs, rectangles). Higher F values were needed for stimuli containing slanted elements or curved surfaces (about 1 Hz increment), overlapping elements at two different depths (about 2.5 Hz increment), or camouflaged overlapping surfaces (> 7 Hz increment). A textured cylindrical surface with a horizontal axis appeared easier to interpret (5.7 Hz) than a pair of slanted segments separated in depth but forming a cross in projection (8 Hz). Training effects were minimal, and F usually increased as disparities were reduced. The hierarchy of difficulties revealed in the study may shed light on various problems that the brain needs to solve during stereoscopic interpretation. During the construction of the three-dimensional percept, the loss of information due to natural decay of the stimuli traces must be compensated by refreshes of visual input. In the discussion an attempt is made to link our results with recent advances in the comprehension of visual scene memory. PMID:23145225

  16. Recruitment of CRISPR-Cas systems by Tn7-like transposons.

    PubMed

    Peters, Joseph E; Makarova, Kira S; Shmakov, Sergey; Koonin, Eugene V

    2017-08-29

    A survey of bacterial and archaeal genomes shows that many Tn7-like transposons contain minimal type I-F CRISPR-Cas systems that consist of fused cas8f and cas5f , cas7f , and cas6f genes and a short CRISPR array. Several small groups of Tn7-like transposons encompass similarly truncated type I-B CRISPR-Cas. This minimal gene complement of the transposon-associated CRISPR-Cas systems implies that they are competent for pre-CRISPR RNA (precrRNA) processing yielding mature crRNAs and target binding but not target cleavage that is required for interference. Phylogenetic analysis demonstrates that evolution of the CRISPR-Cas-containing transposons included a single, ancestral capture of a type I-F locus and two independent instances of type I-B loci capture. We show that the transposon-associated CRISPR arrays contain spacers homologous to plasmid and temperate phage sequences and, in some cases, chromosomal sequences adjacent to the transposon. We hypothesize that the transposon-encoded CRISPR-Cas systems generate displacement (R-loops) in the cognate DNA sites, targeting the transposon to these sites and thus facilitating their spread via plasmids and phages. These findings suggest the existence of RNA-guided transposition and fit the guns-for-hire concept whereby mobile genetic elements capture host defense systems and repurpose them for different stages in the life cycle of the element.

  17. Theory-based and evidence-based design of audit and feedback programmes: examples from two clinical intervention studies.

    PubMed

    Hysong, Sylvia J; Kell, Harrison J; Petersen, Laura A; Campbell, Bryan A; Trautner, Barbara W

    2017-04-01

    Audit and feedback (A&F) is a common intervention used to change healthcare provider behaviour and, thus, improve healthcare quality. Although A&F can be effective its effectiveness varies, often due to the details of how A&F interventions are implemented. Some have suggested that a suitable conceptual framework is needed to organise the elements of A&F and also explain any observed differences in effectiveness. Through two examples from applied research studies, this article demonstrates how a suitable explanatory theory (in this case Kluger & DeNisi's Feedback Intervention Theory (FIT)) can be systematically applied to design better feedback interventions in healthcare settings. Case 1: this study's objective was to reduce inappropriate diagnosis of catheter-associated urinary tract infections (CAUTI) in inpatient wards. Learning to identify the correct clinical course of action from the case details was central to this study; consequently, the feedback intervention featured feedback elements that FIT predicts would best activate learning processes (framing feedback in terms of group performance and providing of correct solution information). We designed a highly personalised, interactive, one-on-one intervention with healthcare providers to improve their capacity to distinguish between CAUTI and asymptomatic bacteruria (ASB) and treat ASB appropriately. Case 2: Simplicity and scalability drove this study's intervention design, employing elements that FIT predicted positively impacted effectiveness yet still facilitated deployment and scalability (eg, delivered via computer, delivered in writing). We designed a web-based, report-style feedback intervention to help primary care physicians improve their care of patients with hypertension. Both studies exhibited significant improvements in their desired outcome and in both cases interventions were received positively by feedback recipients. A&F has been a popular, yet inconsistently implemented and variably effective tool for changing healthcare provider behaviour and, improving healthcare quality. Through the systematic use of theory such as FIT, robust feedback interventions can be designed that yield greater effectiveness. Future work should look to comparative effectiveness of specific design elements and contextual factors that identify A&F as the optimal intervention to effectuate healthcare provider behaviour change. NCT01052545, NCT00302718; post-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  18. The influence of fluorine on phase relations and REE enrichment in alkaline magmas

    NASA Astrophysics Data System (ADS)

    Beard, C. D.; van Hinsberg, V.; Stix, J.; Wilke, M.

    2017-12-01

    Fluorine is a minor element in most magmas, but higher concentrations to wt% levels have been reported in alkaline systems, including those which host economic deposits of REE + HFSE1. Despite low abundance in most natural melts, fluorine has received great attention from the experimental community because it has a strong influence on melt structure, lowering melting points and drastically reducing viscosity. The effect of fluorine on element speciation has important implications for phase relations and the partitioning of trace elements between minerals and melts, thus metal enrichment processes in alkaline magmas. We have experimentally investigated the impact of fluorine on phase relations and partitioning of rare metals, the REE in particular, in evolved alkaline melts. Synthetic glasses of tephriphonolite to phonolite composition were doped with a wide range of elements at trace levels, and fluorine contents were varied from fluorine-free to 2.5 wt%. Experiments were performed water-saturated in an internally heated pressure vessel at 200 MPa with log fO2 at ca. QFM+1, which represents the intrinsic redox conditions of the setup. Charges were heated to super-liquidus conditions for 16 hours, cooled slowly (1˚C/min) to run temperature and subsequently equilibrated for at least 40 hours. Run products were analysed by EPMA and LA-ICP-MS. The experiments produce an equilibrium assemblage of sodic pyroxene, biotite, Fe-oxide, melt, fluid, ±K-feldspar, ±titanite, ±fluorite. Addition of fluorine markedly increases the mode of biotite, which initially buffers melt F content at low levels (< 0.2 wt%). Only in experiments with more than 0.6 wt% F do we observe a significant increase in the melt F-content. Here, fluorine decreases pyroxene/melt partitioning coefficients equally for all REE where pyroxene composition and P-T conditions are equivalent (ca. 1/2 with 0.6% F). We suggest that the formation of REE-F complexes in the melt2 lowers the availability of metals for incorporation into solid phases. An increasing fluorine content of the melt will thus make the REE progressively more incompatible and available for residual enrichment. 1. Vasyukova, O. & Williams-Jones, A. E. Geochim. Cosmochim. Acta 139, 110-130 (2014). 2. Ponader, C. W. & Brown Jr., G. E. Geochim. Cosmochim. Acta 53, 2905-2914 (1989).

  19. Characterization of New Otic Enhancers of the Pou3f4 Gene Reveal Distinct Signaling Pathway Regulation and Spatio-Temporal Patterns

    PubMed Central

    Robert-Moreno, Àlex; Naranjo, Silvia; de la Calle-Mustienes, Elisa; Gómez-Skarmeta, José Luis; Alsina, Berta

    2010-01-01

    POU3F4 is a member of the POU-homedomain transcription factor family with a prominent role in inner ear development. Mutations in the human POU3F4 coding unit leads to X-linked deafness type 3 (DFN3), characterized by conductive hearing loss and progressive sensorineural deafness. Microdeletions found 1 Mb 5′ upstream of the coding region also displayed the same phenotype, suggesting that cis-regulatory elements might be present in that region. Indeed, we and others have recently identified several enhancers at the 1 Mb 5′ upstream interval of the pou3f4 locus. Here we characterize the spatio-temporal patterns of these regulatory elements in zebrafish transgenic lines. We show that the most distal enhancer (HCNR 81675) is activated earlier and drives GFP reporter expression initially to a broad ear domain to progressively restrict to the sensory patches. The proximal enhancer (HCNR 82478) is switched later during development and promotes expression, among in other tissues, in sensory patches from its onset. The third enhancer (HCNR 81728) is also active at later stages in the otic mesenchyme and in the otic epithelium. We also characterize the signaling pathways regulating these enhancers. While HCNR 81675 is regulated by very early signals of retinoic acid, HCNR 82478 is regulated by Fgf activity at a later stage and the HCNR 81728 enhancer is under the control of Hh signaling. Finally, we show that Sox2 and Pax2 transcription factors are bound to HCNR 81675 genomic region during otic development and specific mutations to these transcription factor binding sites abrogates HCNR 81675 enhancer activity. Altogether, our results suggest that pou3f4 expression in inner ear might be under the control of distinct regulatory elements that fine-tune the spatio-temporal activity of this gene and provides novel data on the signaling mechanisms controlling pou3f4 function. PMID:21209840

  20. F3D Image Processing and Analysis for Many - and Multi-core Platforms

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

    F3D is written in OpenCL, so it achieve[sic] platform-portable parallelism on modern mutli-core CPUs and many-core GPUs. The interface and mechanims to access F3D core are written in Java as a plugin for Fiji/ImageJ to deliver several key image-processing algorithms necessary to remove artifacts from micro-tomography data. The algorithms consist of data parallel aware filters that can efficiently utilizes[sic] resources and can work on out of core datasets and scale efficiently across multiple accelerators. Optimizing for data parallel filters, streaming out of core datasets, and efficient resource and memory and data managements over complex execution sequence of filters greatly expeditesmore » any scientific workflow with image processing requirements. F3D performs several different types of 3D image processing operations, such as non-linear filtering using bilateral filtering and/or median filtering and/or morphological operators (MM). F3D gray-level MM operators are one-pass constant time methods that can perform morphological transformations with a line-structuring element oriented in discrete directions. Additionally, MM operators can be applied to gray-scale images, and consist of two parts: (a) a reference shape or structuring element, which is translated over the image, and (b) a mechanism, or operation, that defines the comparisons to be performed between the image and the structuring element. This tool provides a critical component within many complex pipelines such as those for performing automated segmentation of image stacks. F3D is also called a "descendent" of Quant-CT, another software we developed in the past. These two modules are to be integrated in a next version. Further details were reported in: D.M. Ushizima, T. Perciano, H. Krishnan, B. Loring, H. Bale, D. Parkinson, and J. Sethian. Structure recognition from high-resolution images of ceramic composites. IEEE International Conference on Big Data, October 2014.« less

  1. The Effect of Temperature on Kinetics and Diffusion Coefficients of Metallocene Derivatives in Polyol-Based Deep Eutectic Solvents

    PubMed Central

    Bahadori, Laleh; Chakrabarti, Mohammed Harun; Manan, Ninie Suhana Abdul; Hashim, Mohd Ali; Mjalli, Farouq Sabri; AlNashef, Inas Muen; Brandon, Nigel

    2015-01-01

    The temperature dependence of the density, dynamic viscosity and ionic conductivity of several deep eutectic solvents (DESs) containing ammonium-based salts and hydrogen bond donvnors (polyol type) are investigated. The temperature-dependent electrolyte viscosity as a function of molar conductivity is correlated by means of Walden’s rule. The oxidation of ferrocene (Fc/Fc+) and reduction of cobaltocenium (Cc+/Cc) at different temperatures are studied by cyclic voltammetry and potential-step chronoamperometry in DESs. For most DESs, chronoamperometric transients are demonstrated to fit an Arrhenius-type relation to give activation energies for the diffusion of redox couples at different temperatures. The temperature dependence of the measured conductivities of DES1 and DES2 are better correlated with the Vogel-Tamman-Fulcher equation. The kinetics of the Fc/Fc+ and Cc+/Cc electrochemical systems have been investigated over a temperature range from 298 to 338 K. The heterogeneous electron transfer rate constant is then calculated at different temperatures by means of a logarithmic analysis. The glycerol-based DES (DES5) appears suitable for further testing in electrochemical energy storage devices. PMID:26642045

  2. Elemental Representations of Stimuli in Associative Learning

    ERIC Educational Resources Information Center

    Harris, Justin A.

    2006-01-01

    This article reviews evidence and theories concerning the nature of stimulus representations in Pavlovian conditioning. It focuses on the elemental approach developed in stimulus sampling theory (R. C. Atkinson & W. K. Estes, 1963; R. R. Bush & F. Mosteller, 1951b) and extended by I. P. L. McLaren and N. J. Mackintosh (2000, 2002) and contrasts…

  3. 76 FR 6496 - Special Flight Rules Area in the Vicinity of Grand Canyon National Park, Draft Environmental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-04

    ... being considered include: Alternative A Current Condition: Key elements are corridors open year round, annual allocation cap of 93,971, and no quiet technology incentive. Current tours for helicopters and... to quiet technology aircraft. Alternative F Modified Current Condition: Key elements are similar to...

  4. 36. DETAILS AND SECTIONS OF SHIELDING TANK, FUEL ELEMENT SUPPORT ...

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

    36. DETAILS AND SECTIONS OF SHIELDING TANK, FUEL ELEMENT SUPPORT FRAME AND SUPPORT PLATFORM, AND SAFETY MECHANISM ASSEMBLY (SPRING-LOADED HINGE). F.C. TORKELSON DRAWING NUMBER 842-ARVFS-701-S-1. INEL INDEX CODE NUMBER: 075 0701 60 851 151975. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

  5. 1300930

    NASA Image and Video Library

    2013-08-15

    DR. BINAYAK PANDA LOADS A SAMPLE IN THE IMS-6F SECONDARY ION MASS SPECTROSCOPE’S ULTRA HIGH VACUUM CHAMBER. IT IS CAPABLE OF ANALYZING VERY LIGHT ELEMENTS SUCH AS HYDROGEN AND LITHIUM IN ALLOYS. IT CAN ALSO ANALYZE VERY SMALL QUANTITIES OF IMPURITIES IN MATERIALS AT PARTS PER MILLION LEVELS, AND DETERMINE ISOTOPE RATIOS OF ELEMENTS, ALL IN SOLID SAMPLES.

  6. 50 CFR 36.41 - Permits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... Consideration of the last element will include, but is not limited to: (A) The relationship of the real property... alternative sentencing that indicates the penalty is of equal severity to the foregoing elements; or (F) Any... procedure on rights-of-way. (2) Prior to making any adverse decision or order on any permit or an...

  7. Siderophile Element Partitioning between Sulfide- and Silicate melts.

    NASA Astrophysics Data System (ADS)

    Hackler, S.; Rohrbach, A.; Loroch, D. C.; Klemme, S.; Berndt, J.

    2017-12-01

    Different theories concerning the formation of the Earth are debated. Either Earth accreted mostly `dry' or volatile elements were delivered late after core formation was largely inactive [1, 2], or volatile rich material was accreted during the main stages of accretion and core formation [3, 4, 5]. The partitioning behavior of siderophile volatile elements (SVE; S, Se, Te, Tl, Ag, Au, Cd, Bi, Pb, Sn, Cu, Ge, and In) may provide first order constraints whether these element concentrations in Earth's mantle were established before or after core-mantle differentiation or perhaps during both periods by multi stage core formation [6]. A special interest is laid into chalcophile element behavior with respective to the possible formation and segregation of a hadean matte [7]. To examine the influence of sulfur on SVE partitioning between metal-silicate melts, we performed experiments simulating a magma ocean stage evolving from sulfur poor- (low fO2) to more oxidizing sulfur rich- (Fe, Ni)-S melts ( 20 wt% S) towards the end of accretion. We carried out partitioning experiments under various P-T-fO2 conditions with a Bristol type end loaded piston cylinder apparatus (<3 GPa) and a 1000 t walker-type multi-anvil press (3-20 GPa). Our results will be presented at the meeting. References: [1] Albarède F. (2009) Nature, 461, 1227-1233. [2] Ballhaus C. et al. (2013) EPSL, 362, 237-245. [3] Fischer-Gödde M. and Kleine T. (2017) Nature, 541, 525 527. [4] Wade J. and Wood B. J. (2005) EPSL, 236, 78-95. [5] Rubie D. et al. (2016) Science, 253, 1141-1144. [6] Rubie D. et al. (2011) EPSL, 301, 31-42. [7] O'Neill H. St. C. (1991) GCA, 55, 1159-1172.

  8. Geochemical properties of topsoil around the coal mine and thermoelectric power plant.

    PubMed

    Stafilov, Trajče; Šajn, Robert; Arapčeska, Mila; Kungulovski, Ivan; Alijagić, Jasminka

    2018-03-19

    The results of the systematic study of the spatial distribution of trace metals in surface soil over the Bitola region, Republic of Macedonia, known for its coal mine and thermo-electrical power plant activities are reported. The investigated region (3200 km 2 ) is covered by a sparse sampling grid of 5 × 5 km, but in the urban zone and around the thermoelectric power plant the sampling grid is denser (1 × 1 km). In total, 229 soil samples from 149 locations were collected including top-soil (0-5 cm) and bottom-soil samples (20-30 cm and 0-30 cm). Inductively coupled plasma - atomic emission spectrometry (ICP-AES) was applied for the determinations of 21 elements (Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, Sr, V and Zn). Based on the results of factor analyses, three geogenic associations of elements have been defined: F1 (Fe, Ni, V, Co, Cr, Mn and Li), F2 (Zn, B, Cu, Cd, Na and K) and F3 (Ca, Sr, Mg, Ba and Al). Even typical trace metals such as As, Cd, Cu, Ni, P, Pb and Zn are not isolated into anthropogenic geochemical associations by multivariate statistical methods still show some trends of local anthropogenic enrichment. The distribution maps for each analyzed element is showing the higher content of these elements in soil samples collected around the thermoelectric power plants than their average content for the soil samples collected from the whole Bitola Region. It was found that this enrichment is a result of the pollution by fly ash from coal burning which deposited near the plant having a high content of these elements.

  9. Ultrasonic Evaluation of the Pull-Off Adhesion between Added Repair Layer and a Concrete Substrate

    NASA Astrophysics Data System (ADS)

    Czarnecki, Slawomir

    2017-10-01

    This paper concerns the evaluation of the pull-off adhesion between a concrete added repair layer with variable thickness and a concrete substrate, based on parameters assessed using ultrasonic pulse velocity (UPV) method. In construction practice, the experimental determination of pull-off adhesion f b, between added repair layer and a concrete substrate is necessary to assess the quality of repair. This is usually carried out with the use of pull-off method which results in local damage of the added concrete layer in all the testing areas. Bearing this in mind, it is important to describe the method without these disadvantages. The prediction of the pull-off adhesion of the two-layer concrete elements with variable thickness of each layer might be provided by means of UPV method with two-sided access to the investigated element. For this purpose, two-layered cylindrical specimens were obtained by drilling the borehole from a large size specially prepared concrete element. Those two-layer elements were made out of concrete substrate layer and Polymer Cement Concrete (PCC) mortar as an added repair layer. The values of pull-off adhesion f b of the elements were determined before obtaining the samples by using the semi-destructive pull-off method. The ultrasonic wave velocity was determined in samples with variable thickness of each layer and was then compared to theoretical ultrasonic wave velocity predicted for those specimens. The regression curve for the dependence of velocity and pull-off adhesion, determined by the pulloff method, was made. It has been proved that together with an increase of ratio of investigated ultrasonic wave velocity divided by theoretical ultrasonic wave velocity, the pull-off adhesion value f b between added repair layer with variable thickness and a substrate layer also increases.

  10. Trace element geochemistry of volcanic gases and particles from 1983-1984 eruptive episodes of Kilauea Volcano

    NASA Astrophysics Data System (ADS)

    Crowe, Bruce M.; Finnegan, David L.; Zoller, William H.; Boynton, William V.

    1987-12-01

    Compositional data have been obtained for volcanic gases and particles collected from fume emitted at the Pu'u O'o vent on the east rift zone of Kilauea volcano. The samples were collected by pumping fume through a filter pack system consisting of a front stage particulate filter followed by four base-treated filters (7LiOH). Particles and condensed phases are trapped on the particulate filter, and acidic gases are collected on the treated filters. The filters are analyzed for 30 elements by instrumental neutron activation analysis. Fume samples were collected from the Pu'u O'o vent for two eruptive episodes: (1) 7 days after episode 11 (cooling vent samples) and (2) the waning stage of episode 13 (active vent samples). Additional samples were collected by aircraft from the gas plume released during the lava fountaining phase of episode 17 (aircraft samples). Element concentrations in the vent gases were > 104 μg m-3 for S, Cl, and F. Enrichment factors (EFs) for the volcanic fume versus the source magma were calculated using the volatile element Br as the reference element for normalization and the U.S. Geological Survey standard BHVO-1 as the magma standard. This removes the ash dilution effect obtained by using an ash constituent (Al, Sc, or Mg) as the reference element. Bromine-normalized EFs (× 105) range from 101 to 102 for Na, K, and Cu; 102 to 105 for Zn, W, Sb, In, Ir, Ag, F, and As; and > 105 for Au, Cd, Re, Cl, Se, and S. The highest enrichment factors are for aircraft samples collected during the most gas-rich phase of an eruption cycle. Metal and volatile-element data form two groups: (1) elements showing little or no variation in abundance ratios with sample type (group 1: Cl, Br, and Re) and (2) elements that show significant variation in abundance ratios by sample type (group 2: Zn, W, Sb, In, Ir, Au, and Cd). Bivariate plots of elements of the first group versus elements of the second group separate by sample type. The separation corresponds to samples collected during eruptive activity versus samples collected during repose periods. Monitoring trace metal ratios in volcanic fume could provide an additional tool for predicting volcanic eruptions. The F/Cl ratio of cooling vent samples is higher than those of active vent or aircraft samples, and the ratio is inversely correlated with EFs for most volatile metals.

  11. Connectivity of glass structure. Oxygen number

    NASA Astrophysics Data System (ADS)

    Medvedev, E. F.; Min'ko, N. I.

    2018-03-01

    With reference to mathematics, crystal chemistry and chemical technology of synthesis of glass structures in the solution (sol-gel technology), the paper is devoted to the study of the degree of connectivity of a silicon-oxygen backbone (fSi) and the oxygen number (R) [1]. It reveals logical contradictions and uncertainty of mathematical expressions of parameters, since fSi is not similar to the oxygen number. The connectivity of any structure is a result of various types of bonds: ion-covalent, donor-acceptor, hydrogen bonds, etc. Besides, alongside with SiO2, many glass compositions contain other glass-forming elements due to tetrahedral sites thus formed. The connectivity function of a glassy network with any set of glass-forming elements is roughly ensured by connectivity factor Y [2], which has monovalent elements loosening a glassy network. The paper considers the existence of various structural motives in hydrogen-impermeable glasses containing B2O3, Al2O3, PbO, Na2O, K2O and rare-earth elements. Hence, it also describes gradual nucleation, change of crystal forms, and structure consolidation in the process of substance intake from a matrix solution according to sol-gel technology. The crystal form varied from two-dimensional plates to three-dimensional and dendritical ones [3]. Alternative parameters, such as the oxygen number (O) and the structure connectivity factor (Y), were suggested. Functional dependence of Y=f(O) to forecast the generated structures was obtained for two- and multicomponent glass compositions.

  12. Nonstoichiometry in inorganic fluorides: I. Nonstoichiometry in MF m - RF n ( m < n ≤ 4) systems

    NASA Astrophysics Data System (ADS)

    Sobolev, B. P.

    2012-05-01

    The manifestation of gross nonstoichiometry in MF m - RF n systems ( m < n ≤ 4) has been studied. Fluorides of 34 elements, in the systems of which phases of practical interest are formed, are chosen. To search for new phases of complex composition, a program for studying the phase diagrams of the condensed state (˜200 systems) has been carried out at the Institute of Crystallography, Russian Academy of Sciences. The main products of high-temperature interactions of the fluorides of elements with different valences ( m ≠ n) are grossly nonstoichiometric phases of two structural types: fluorite (CaF2) and tysonite (LaF3). Systems of fluorides of 27 elements ( M 1+ = Na, K; M 2+ = Ca, Sr, Ba, Cd, Pb; R 3+ = Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; R 4+ = Zr, Hf, Th, U) are selected; nonstoichiometric M 1 - x R x F m(1 - x) + nx phases, which are of greatest practical interest, are formed in these systems. The gross nonstoichiometry in inorganic fluorides is most pronounced in 80 MF2 - RF3 systems ( M = Ca, Sr, Ba, Cd, Pb; R are rare earth elements). The problems related to the growth of single crystals of nonstoichiometric phases and basic fields of their application as new fluoride multicomponent materials, the properties of which are controlled by the defect structure, are considered.

  13. Calculation of Scattering Amplitude Without Partial Analysis. II; Inclusion of Exchange

    NASA Technical Reports Server (NTRS)

    Temkin, Aaron; Shertzer, J.; Fisher, Richard R. (Technical Monitor)

    2002-01-01

    There was a method for calculating the whole scattering amplitude, f(Omega(sub k)), directly. The idea was to calculate the complete wave function Psi numerically, and use it in an integral expression for f, which can be reduced to a 2 dimensional quadrature. The original application was for e-H scattering without exchange. There the Schrodinger reduces a 2-d partial differential equation (pde), which was solved using the finite element method (FEM). Here we extend the method to the exchange approximation. The S.E. can be reduced to a pair of coupled pde's, which are again solved by the FEM. The formal expression for f(Omega(sub k)) consists two integrals, f+/- = f(sub d) +/- f(sub e); f(sub d) is formally the same integral as the no-exchange f. We have also succeeded in reducing f(sub e) to a 2-d integral. Results will be presented at the meeting.

  14. Experimental and natural partitioning behaviour of trace-elements between hydrous evolved melts, amphibole, plagioclase, and clinopyroxene at shallow crustal conditions

    NASA Astrophysics Data System (ADS)

    Iveson, A. A.; Webster, J. D.; Rowe, M. C.; Neill, O. K.

    2016-12-01

    New experimental data for crystal-melt partitioning behaviour of a suite of trace-elements are presented. Hydrous rhyo-dacitic starting glasses from Mt. Usu, Japan, were doped with Li, Sc, Cr, Mn, Ni, Cu, Zn, Ga, Rb, Sr, Y, Nb, Mo, Ba, W, and Pb. Aqueous solutions were added such that the volatile phase(s) coexisting with amphibole, plagioclase, and clinopyroxene at run conditions buffered the S, F, and Cl contents of the melts. Internally-heated pressure vessel experiments were conducted at 750-850 °C, 1.0-4.0 Kbar, and ƒO2 ≈ NNO-NNO+2 log units. Major- and minor-element concentrations in the phenocrysts and glasses were analysed by EPMA, and trace-element contents by SIMS and/or LA-ICP-MS. The long run durations, homogeneous glasses, and minimal compositional zonation of crystals suggest that near-equilibrium conditions were achieved. Results of multiple phenocryst and glass analyses show that Nernst-type crystal-melt partition coefficients for these elements range from strongly incompatible e.g. Dmineral/melt ≈ 0 for Nb into plagioclase, to moderately incompatible e.g. Dmineral/melt ≈ 0.75 for Ga into amphibole, to strongly compatible e.g. Dmineral/melt > 50 for Ni into amphibole and clinopyroxene. Furthermore, unlike other elements investigated, partitioning of Li between phenocrysts and melt is similar for all three phases, with average DLicpx/melt ≈ 0.26 > DLiplag/melt ≈ 0.24 > DLiamph/melt ≈ 0.19. Relative to major-element composition of crystalline phases, the temperature, pressure, and ƒO2 conditions do not appear to strongly affect this behaviour. The incorporation of F and Cl into amphiboles is also consistent with the Fe-F and Mg-Cl crystallographic avoidance principles. Importantly, across two orders of magnitude in concentration, partitioning behaviours of all analysed trace-elements appear to obey Henry's Law. The experimental data are integrated with new amphibole, plagioclase, and pyroxene analyses from eruptive products of Augustine and Mt. St. Helens volcanoes. The results are applicable to understanding processes governing melt evolution during shallow magma storage and formation of economic metal deposits, where the crystallisation of porphyry-type magmas leads to fluid exsolution, and enrichment and transport of such trace- and ore-elements.

  15. Coulomb matrix elements in multi-orbital Hubbard models.

    PubMed

    Bünemann, Jörg; Gebhard, Florian

    2017-04-26

    Coulomb matrix elements are needed in all studies in solid-state theory that are based on Hubbard-type multi-orbital models. Due to symmetries, the matrix elements are not independent. We determine a set of independent Coulomb parameters for a d-shell and an f-shell and all point groups with up to 16 elements (O h , O, T d , T h , D 6h , and D 4h ). Furthermore, we express all other matrix elements as a function of the independent Coulomb parameters. Apart from the solution of the general point-group problem we investigate in detail the spherical approximation and first-order corrections to the spherical approximation.

  16. Investigations on the direct introduction of cigarette smoke for trace elements analysis by inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Chang, Michael J.; Naworal, John D.; Walker, Kathleen; Connell, Chris T.

    2003-11-01

    Direct introduction of mainstream cigarette smoke into an inductively coupled plasma mass spectrometry (ICP-MS) has been investigated with respect to its feasibility for on-line analysis of trace elements. An automated apparatus was designed and built interfacing a smoking machine with an ICP-MS for smoke generation, collection, injection and analysis. Major and minor elements present in the particulate phase and the gas phase of mainstream cigarette smoke of 2R4F reference cigarettes have been qualitatively identified by examination of their full mass spectra. This method provides a rapid-screening analysis of the transfer of trace elements into mainstream smoke during cigarette combustion. A full suite of elements present in the whole cigarette smoke has been identified, including As, B, Ba, Br, Cd, Cl, Cs, Cu, Hg, I, K, Li, Mn, Na, Pb, Rb, Sb, Sn, Tl and Zn. Of these elements, the major portions of B, Ba, Cs, Cu, K, Li, Mn, Na, Pb, Rb, Sn, Tl and Zn are present in the particulate phase, whereas the major portion of Hg is present in the gas phase. As, Br, Cd, Cl, I and Sb exist in a distribution between the gas phase and the particulate phase. Depending on the element, the precision of measurement ranges from 5 to 25% in terms of relative standard deviation of peak height and peak area, based on the fourth puff of 2R4F mainstream cigarette smoke analyzed in five smoking replicates.

  17. Structural and electronic parameters of ferroelectric KWOF

    NASA Astrophysics Data System (ADS)

    Atuchin, V. V.; Gavrilova, T. A.; Kesler, V. G.; Molokeev, M. S.; Aleksandrov, K. S.

    2010-11-01

    The low-temperature ferroelectric G2 polymorph of K 3WO 3F 3 oxyfluoride is formed by chemical synthesis. The electronic parameters of G2-K 3WO 3F 3 have been measured by X-ray photoelectron spectroscopy under excitation with Al Kα radiation (1486.6 eV). Detailed spectra have been recorded for all element core levels and Auger lines. The chemical bonding effects in the WO 3F 3 and WO 6 octahedrons are considered by using the binding energy difference ΔBE(O-W)=BE(O 1s)-BE(W 4f).

  18. Environmental hazards of fluoride in volcanic ash: a case study from Ruapehu volcano, New Zealand

    NASA Astrophysics Data System (ADS)

    Cronin, Shane J.; Neall, V. E.; Lecointre, J. A.; Hedley, M. J.; Loganathan, P.

    2003-03-01

    The vent-hosted hydrothermal system of Ruapehu volcano is normally covered by a c. 10 million m 3 acidic crater lake where volcanic gases accumulate. Through analysis of eruption observations, granulometry, mineralogy and chemistry of volcanic ash from the 1995-1996 Ruapehu eruptions we report on the varying influences on environmental hazards associated with the deposits. All measured parameters are more dependent on the eruptive style than on distance from the vent. Early phreatic and phreatomagmatic eruption phases from crater lakes similar to that on Ruapehu are likely to contain the greatest concentrations of environmentally significant elements, especially sulphur and fluoride. These elements are contained within altered xenolithic material extracted from the hydrothermal system by steam explosions, as well as in residue hydrothermal fluids adsorbed on to particle surfaces. In particular, total F in the ash may be enriched by a factor of 6 relative to original magmatic contents, although immediately soluble F does not show such dramatic increases. Highly soluble NaF and CaSiF 6 phases, demonstrated to be the carriers of 'available' F in purely magmatic eruptive systems, are probably not dominant in the products of phreatomagmatic eruptions through hydrothermal systems. Instead, slowly soluble compounds such as CaF 2, AlF 3 and Ca 5(PO 4) 3F dominate. Fluoride in these phases is released over longer periods, where only one third is leached in a single 24-h water extraction. This implies that estimation of soluble F in such ashes based on a single leach leads to underestimation of the F impact, especially of a potential longer-term environmental hazard. In addition, a large proportion of the total F in the ash is apparently soluble in the digestive system of grazing animals. In the Ruapehu case this led to several thousand sheep deaths from fluorosis.

  19. The Redox Dynamics of Iron in a Seasonally Waterlogged Forest Soil (Chaux Forest, Eastern France) Traced with Rare Earth Element Distribution Patterns

    NASA Astrophysics Data System (ADS)

    Steinmann, M.; Floch, A. L.; Lucot, E.; Badot, P. M.

    2014-12-01

    The oxyhydroxides of iron are common soil minerals and known to control the availability of various major and trace elements essential for biogeochemical processes. We present a study from acidic natural forest soils, where reducing redox conditions due to seasonal waterlogging lead to the dissolution of Fe-oxyhydroxides, and to the release of Fe to soil water. In order to study in detail the mechanism of redox cycling of Fe, we used Rare Earth Element (REE) distribution patterns, because an earlier study has shown that they are a suitable tool to identify trace metal sources during soil reduction in wetland soils (Davranche et al., 2011). The REE patterns of soil leachates obtained with the modified 3-step BCR extraction scheme of Rauret et al., (1999) were compared with those of natural soil water. The adsorbed fractions (F1 leach), the reducible fraction of the deepest soil horizon H4 (F2 leach, 50-120 cm), and the oxidizable fractions of horizons H2 to H4 (F3 leachs, 24-120 cm) yielded REE patterns almost identical to soil water (see figure), showing that the REE and trace metal content of soil water was mainly derived from the F1 pool, and from the F2 and F3 pools of the clay mineral-rich deep soil horizons. In contrast, the F2 leach mobilized mainly Fe-oxyhydroxides associated with organic matter of the surface soil and yielded REE patterns significantly different from those of soil water. These results suggest that the trace metal content of soil water in hydromorphic soils is primarily controlled by the clay fraction of the deeper soil horizons and not by organic matter and related Fe-oxyhydroxides of the surface soil. Additional analyses are in progress in order to verify whether the REE and trace metals of the deeper soil horizons were directly derived from clay minerals or from associated Fe-oxyhydroxide coatings. Refs cited: Davranche et al. (2011), Chem. Geol. 284; Rauret et al. (1999), J. Environ. Monit. 1.

  20. CERAMIC FUEL ELEMENT MATERIAL FOR A NEUTRONIC REACTOR AND METHOD OF FABRICATING SAME

    DOEpatents

    Duckworth, W.H.

    1957-12-01

    This patent relates to ceramic composition, and to neutronic reactor fuel elements formed therefrom. These ceramic elements have high density and excellent strength characteristics and are formed by conventional ceramic casting and sintering at a temperature of about 2700 deg F in a nitrogen atmosphere. The composition consists of silicon carbide, silicon, uranium oxide and a very small percentage of molybdenum. Compositions containing molybdenum are markedly stronger than those lacking this ingredient.

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