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Sample records for cerium 139

  1. Cerium Oxide and Cerium Compounds

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 08 / 002F www.epa.gov / iris TOXICOLOGICAL REVIEW OF Cerium Oxide and Cerium Compounds ( CAS No . 1306 - 38 - 3 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2009 U.S . Environmental Protection Agency Washington , DC ii DISCLAIMER Th

  2. PLUTONIUM-CERIUM ALLOY

    DOEpatents

    Coffinberry, A.S.

    1959-01-01

    An alloy is presented for use as a reactor fuel. The binary alloy consists essentially of from about 5 to 90 atomic per cent cerium and the balance being plutonium. A complete phase diagram for the cerium--plutonium system is given.

  3. Cerium compounds as scintillators

    SciTech Connect

    Wojtowicz, A.J.; Berman, E.; Koepke, C.; Lempicki, A.

    1991-01-01

    Stoichiometric Ce-materials with negligible Ce-Ce interactions should have superior scintillator properties. We present two materials: CeF{sub 3} and Ce{sub x}La{sub 1-x}P{sub 5}O{sub 14}. While cerium trifluoride is a known scintillator, pentaphosphate is of a limited usefulness, except as a remarkable model material. We show that quenching in fluoride is responsible for loss of 50% of the light output and is the cause of the, so-called, ultra fast component (2 ns). Light output of fluoride (about 50% of BGO) could be significantly improved. Deeper understanding of Ce-systems is needed to fully exploit their potentials. 10 figs., 6 refs.

  4. Cerium compounds as scintillators

    SciTech Connect

    Wojtowicz, A.J.; Berman, E.; Koepke, C.; Lempicki, A.

    1991-12-31

    Stoichiometric Ce-materials with negligible Ce-Ce interactions should have superior scintillator properties. We present two materials: CeF{sub 3} and Ce{sub x}La{sub 1-x}P{sub 5}O{sub 14}. While cerium trifluoride is a known scintillator, pentaphosphate is of a limited usefulness, except as a remarkable model material. We show that quenching in fluoride is responsible for loss of 50% of the light output and is the cause of the, so-called, ultra fast component (2 ns). Light output of fluoride (about 50% of BGO) could be significantly improved. Deeper understanding of Ce-systems is needed to fully exploit their potentials. 10 figs., 6 refs.

  5. Preparation of cerium halide solvate complexes

    DOEpatents

    Vasudevan, Kalyan V; Smith, Nickolaus A; Gordon, John C; McKigney, Edward A; Muenchaussen, Ross E

    2013-08-06

    Crystals of a solvated cerium(III) halide solvate complex resulted from a process of forming a paste of a cerium(III) halide in an ionic liquid, adding a solvent to the paste, removing any undissolved solid, and then cooling the liquid phase. Diffusing a solvent vapor into the liquid phase also resulted in crystals of a solvated cerium(III) halide complex.

  6. PLUTONIUM-CERIUM-COBALT AND PLUTONIUM-CERIUM-NICKEL ALLOYS

    DOEpatents

    Coffinberry, A.S.

    1959-08-25

    >New plutonium-base teroary alloys useful as liquid reactor fuels are described. The alloys consist of 10 to 20 atomic percent cobalt with the remainder plutonium and cerium in any desired proportion, with the plutonium not in excess of 88 atomic percent; or, of from 10 to 25 atomic percent nickel (or mixture of nickel and cobalt) with the remainder plutonium and cerium in any desired proportion, with the plutonium not in excess of 86 atomic percent. The stated advantages of these alloys over unalloyed plutonium for reactor fuel use are a lower melting point and a wide range of permissible plutonium dilution.

  7. Cerium ion conducting solid electrolyte

    NASA Astrophysics Data System (ADS)

    Hasegawa, Yasunori; Imanaka, Nobuhito; Adachi, Gin-ya

    2003-02-01

    A cerium ion conducting solid electrolyte, (Ce xZr 1- x) 4/4- xNb(PO 4) 3, was successfully realized with the NASICON-type structure which possesses a three-dimensional network, especially suitable for bulky ion migration. The cerium ion conductivity exceeds approximately one order of magnitude in comparison to that of the rare-earth ion conducting R2(WO 4) 3 and R1/3Zr 2(PO 4) 3 ( R=Sc, Y, Eu-Lu) series and the value is in the range between typical oxide anion conductors of yttria stabilized zirconia (YSZ) and calcia stabilized zirconia (CSZ). Since cerium ion has been demonstrated to be another migrating ion species in solid electrolyte field, a promising application for various functional materials is greatly expected.

  8. PLUTONIUM-CERIUM-COPPER ALLOYS

    DOEpatents

    Coffinberry, A.S.

    1959-05-12

    A low melting point plutonium alloy useful as fuel is a homogeneous liquid metal fueled nuclear reactor is described. Vessels of tungsten or tantalum are useful to contain the alloy which consists essentially of from 10 to 30 atomic per cent copper and the balance plutonium and cerium. with the plutontum not in excess of 50 atomic per cent.

  9. IRIS Toxicological Review of Cerium Oxide and Cerium Compounds (External Review Draft)

    EPA Science Inventory

    EPA conducted a peer review of the scientific basis supporting the human health hazard and dose-response assessment of cerium oxide and cerium compounds that will appear on the Integrated Risk Information System (IRIS) database.

  10. Nanoparticle cerium oxide and mixed cerium oxides for improved fuel cell lifetime

    NASA Astrophysics Data System (ADS)

    Stewart, Stephen Michael

    While there is a rich body of literature concerning of properties of bulk cerium oxide and cerium cations in solution, the discussion has been inappropriately applied to nanoscale cerium oxide resulting in many unexpected or unexplained results. In particular, there is very limited understanding about the properties of cerium oxide and its potential use as a radical scavenger, and how the catalytic properties of cerium oxide change as the particle size approaches the nanoscale. For example, the involvement of Ce+4 and Ce+3 cations in reactions such as hydrogen peroxide decomposition have been investigated for both cerium cations and bulk cerium oxide. However, while both are assumed to decompose hydrogen peroxide through the same mechanism, whereby Ce+4 is involved in peroxide decomposition while Ce +3 is involved in radical scavenging, there has been very little done to address how the selectivity and activity of these reactions are affected by changing the majority cation population, as cerium cations in solution are predominantly in the +3 oxidation state while cerium cations are predominantly in the +4 oxidation state in cerium oxide. This matter is further complicated in cerium oxide nanoparticles where the surface concentration of Ce +3 cations is increased due to particle curvature effects. Due to the potential of controlling the surface cerium oxidation state using particle size and using this control to change the catalytic properties, this project investigated the effect of particle size and composition and the activity and selectivity of cerium oxide nanoparticles, and has served to expand the understanding of the properties of pure and mixed nanoparticle cerium oxide. This work explains the metric developed for measuring the catalytic properties of pure and mixed cerium oxide nanoparticles, which is also good at predicting the immediate and long-term behavior of nanoparticles in hydrogen fuel cells. This work also directly demonstrates praseodymium

  11. Grain Growth in Cerium Metal

    NASA Astrophysics Data System (ADS)

    Cooley, Jason; Katz, Martha; Mielke, Charles; Montalvo, Joel

    We report on grain growth in forged and rolled cerium plate for temperatures from 350 to 700 degrees C and times from 30 to 120 minutes. The cerium was made by arc-melting into a 25 mm deep by 80 mm diameter copper mold. The resulting disk was forged at room temperature to a 25% reduction of thickness four times with a 350 degree C strain relief heat treatment for 60 minutes between forging steps. The resulting 8 mm thick plate was clock rolled at room temperature to a 25% reduction of thickness three times with a 350 C strain relief heat treatment between steps resulting in a plate approximately 3 mm thick. 5 x 10 mm coupons were cut from the plate for the grain growth study.

  12. ADSORPTION OF CERIUM VALUES FROM AQUEOUS SOLUTIONS

    DOEpatents

    Roberts, F.P.

    1963-08-13

    Cerium can be removed from aqueous nitric acid (2 to 13 M) solutions by passing the latter over a PbO/sub 2/-containing anion exchange resin. The cerium is taken up by the resin, while any lanthanides, yttrium, and strontium present remain in the solution. (AEC)

  13. Formulation and method for preparing gels comprising hydrous cerium oxide

    DOEpatents

    Collins, Jack L; Chi, Anthony

    2013-05-07

    Formulations useful for preparing hydrous cerium oxide gels contain a metal salt including cerium, an organic base, and a complexing agent. Methods for preparing gels containing hydrous cerium oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including cerium, an organic base, and a complexing agent.

  14. Writing 139: An Instructor's Manual.

    ERIC Educational Resources Information Center

    Zimmerman, Ray, Ed.; And Others

    This instructor's manual is designed to improve the instructional support program for Writing 139, an interdisciplinary advanced composition class at the University of California, Irvine taught primarily by graduate student teaching assistants. After a brief history and overview of the course, the manual presents sections that address the…

  15. Virus removal by biogenic cerium.

    PubMed

    De Gusseme, Bart; Du Laing, Gijs; Hennebel, Tom; Renard, Piet; Chidambaram, Dev; Fitts, Jeffrey P; Bruneel, Els; Van Driessche, Isabel; Verbeken, Kim; Boon, Nico; Verstraete, Willy

    2010-08-15

    The rare earth element cerium has been known to exert antifungal and antibacterial properties in the oxidation states +III and +IV. This study reports on an innovative strategy for virus removal in drinking water by the combination of Ce(III) on a bacterial carrier matrix. The biogenic cerium (bio-Ce) was produced by addition of aqueous Ce(III) to actively growing cultures of either freshwater manganese-oxidizing bacteria (MOB) Leptothrix discophora or Pseudomonas putida MnB29. X-ray absorption spectroscopy results indicated that Ce remained in its trivalent state on the bacterial surface. The spectra were consistent with Ce(III) ions associated with the phosphoryl groups of the bacterial cell wall. In disinfection assays using a bacteriophage as model, it was demonstrated that bio-Ce exhibited antiviral properties. A 4.4 log decrease of the phage was observed after 2 h of contact with 50 mg L(-1) bio-Ce. Given the fact that virus removal with 50 mg L(-1) Ce(III) as CeNO(3) was lower, the presence of the bacterial carrier matrix in bio-Ce significantly enhanced virus removal. PMID:20704235

  16. Virus Removal by Biogenic Cerium

    SciTech Connect

    De Gusseme, B.; Du Laing, G; Hennebel, T; Renard, P; Chidambaram, D; Fitts, J; Bruneel, E; Van Driessche, I; Verbeken, K; et. al.

    2010-01-01

    The rare earth element cerium has been known to exert antifungal and antibacterial properties in the oxidation states +III and +IV. This study reports on an innovative strategy for virus removal in drinking water by the combination of Ce(III) on a bacterial carrier matrix. The biogenic cerium (bio-Ce) was produced by addition of aqueous Ce(III) to actively growing cultures of either freshwater manganese-oxidizing bacteria (MOB) Leptothrix discophora or Pseudomonas putida MnB29. X-ray absorption spectroscopy results indicated that Ce remained in its trivalent state on the bacterial surface. The spectra were consistent with Ce(III) ions associated with the phosphoryl groups of the bacterial cell wall. In disinfection assays using a bacteriophage as model, it was demonstrated that bio-Ce exhibited antiviral properties. A 4.4 log decrease of the phage was observed after 2 h of contact with 50 mg L{sup -1} bio-Ce. Given the fact that virus removal with 50 mg L{sup -1} Ce(III) as CeNO{sub 3} was lower, the presence of the bacterial carrier matrix in bio-Ce significantly enhanced virus removal.

  17. 33 CFR 117.139 - White River.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St....

  18. 33 CFR 117.139 - White River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St....

  19. 33 CFR 117.139 - White River.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St....

  20. 33 CFR 117.139 - White River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St....

  1. 33 CFR 117.139 - White River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St....

  2. 14 CFR 139.309 - Safety areas.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Safety areas. 139.309 Section 139.309... Operations § 139.309 Safety areas. (a) In a manner authorized by the Administrator, each certificate holder must provide and maintain, for each runway and taxiway that is available for air carrier use, a...

  3. 14 CFR 139.309 - Safety areas.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Safety areas. 139.309 Section 139.309... Operations § 139.309 Safety areas. (a) In a manner authorized by the Administrator, each certificate holder must provide and maintain, for each runway and taxiway that is available for air carrier use, a...

  4. 14 CFR 139.309 - Safety areas.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Safety areas. 139.309 Section 139.309... Operations § 139.309 Safety areas. (a) In a manner authorized by the Administrator, each certificate holder must provide and maintain, for each runway and taxiway that is available for air carrier use, a...

  5. 14 CFR 139.309 - Safety areas.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Safety areas. 139.309 Section 139.309... Operations § 139.309 Safety areas. (a) In a manner authorized by the Administrator, each certificate holder must provide and maintain, for each runway and taxiway that is available for air carrier use, a...

  6. 14 CFR 139.335 - Public protection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Public protection. 139.335 Section 139.335 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... Operations § 139.335 Public protection. (a) In a manner authorized by the Administrator, each...

  7. 49 CFR 37.139 - Plan contents.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Administration joint planning regulation (49 CFR part 613 and 23 CFR part 450). In a service area which is... 49 Transportation 1 2012-10-01 2012-10-01 false Plan contents. 37.139 Section 37.139... DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.139 Plan contents. Each plan...

  8. 49 CFR 37.139 - Plan contents.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Administration joint planning regulation (49 CFR part 613 and 23 CFR part 450). In a service area which is... 49 Transportation 1 2013-10-01 2013-10-01 false Plan contents. 37.139 Section 37.139... DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.139 Plan contents. Each plan...

  9. 14 CFR 139.335 - Public protection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Public protection. 139.335 Section 139.335... Operations § 139.335 Public protection. (a) In a manner authorized by the Administrator, each certificate... persons or vehicles; and (2) Reasonable protection of persons and property from aircraft blast....

  10. 14 CFR 139.335 - Public protection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Public protection. 139.335 Section 139.335... Operations § 139.335 Public protection. (a) In a manner authorized by the Administrator, each certificate... persons or vehicles; and (2) Reasonable protection of persons and property from aircraft blast....

  11. 14 CFR 139.309 - Safety areas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Safety areas. 139.309 Section 139.309... Operations § 139.309 Safety areas. (a) In a manner authorized by the Administrator, each certificate holder... area of at least the dimensions that— (1) Existed on December 31, 1987, if the runway or taxiway had...

  12. 14 CFR 139.307 - Unpaved areas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Unpaved areas. 139.307 Section 139.307... Operations § 139.307 Unpaved areas. (a) In a manner authorized by the Administrator, each certificate holder..., or loading ramp and parking area on the airport that is available for air carrier use as follows:...

  13. 7 CFR 15.139 - Oral argument.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... oral argument on all parties and will set forth the order of presentation and the amount of time... 7 Agriculture 1 2010-01-01 2010-01-01 false Oral argument. 15.139 Section 15.139 Agriculture..., Decisions and Administrative Review Under the Civil Rights Act of 1964 Posthearing Procedures § 15.139...

  14. 10 CFR 13.9 - Answer.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Answer. 13.9 Section 13.9 Energy NUCLEAR REGULATORY COMMISSION PROGRAM FRAUD CIVIL REMEDIES § 13.9 Answer. (a) The defendant may request a hearing by filing an answer with the reviewing official within thirty (30) days of service of the complaint. Service of...

  15. 40 CFR 52.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 3 2012-07-01 2012-07-01 false 52.139 Section 52.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.139...

  16. 40 CFR 52.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false 52.139 Section 52.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.139...

  17. 40 CFR 52.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 3 2014-07-01 2014-07-01 false 52.139 Section 52.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.139...

  18. 40 CFR 52.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 3 2013-07-01 2013-07-01 false 52.139 Section 52.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.139...

  19. 40 CFR 52.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 3 2011-07-01 2011-07-01 false 52.139 Section 52.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.139...

  20. 14 CFR 21.139 - Quality control.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Quality control. 21.139 Section 21.139... PROCEDURES FOR PRODUCTS AND PARTS Production Certificates § 21.139 Quality control. The applicant must show that he has established and can maintain a quality control system for any product, for which...

  1. 14 CFR 21.139 - Quality control.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Quality control. 21.139 Section 21.139... PROCEDURES FOR PRODUCTS AND PARTS Production Certificates § 21.139 Quality control. The applicant must show that he has established and can maintain a quality control system for any product, for which...

  2. 49 CFR 37.139 - Plan contents.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Administration joint planning regulation (49 CFR part 613 and 23 CFR part 450). In a service area which is... 49 Transportation 1 2010-10-01 2010-10-01 false Plan contents. 37.139 Section 37.139... DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.139 Plan contents. Each plan...

  3. 29 CFR 780.139 - Pea vining.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Pea vining. 780.139 Section 780.139 Labor Regulations... âsuch Farming Operationâ-of the Farmer § 780.139 Pea vining. Vining employees of a pea vinery located on a farm, who vine only the peas grown on that particular farm, are engaged in agriculture. If...

  4. 29 CFR 780.139 - Pea vining.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Pea vining. 780.139 Section 780.139 Labor Regulations... âsuch Farming Operationâ-of the Farmer § 780.139 Pea vining. Vining employees of a pea vinery located on a farm, who vine only the peas grown on that particular farm, are engaged in agriculture. If...

  5. 29 CFR 780.139 - Pea vining.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Pea vining. 780.139 Section 780.139 Labor Regulations... âsuch Farming Operationâ-of the Farmer § 780.139 Pea vining. Vining employees of a pea vinery located on a farm, who vine only the peas grown on that particular farm, are engaged in agriculture. If...

  6. 29 CFR 780.139 - Pea vining.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Pea vining. 780.139 Section 780.139 Labor Regulations... âsuch Farming Operationâ-of the Farmer § 780.139 Pea vining. Vining employees of a pea vinery located on a farm, who vine only the peas grown on that particular farm, are engaged in agriculture. If...

  7. 6 CFR 13.9 - Answer.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 6 Domestic Security 1 2011-01-01 2011-01-01 false Answer. 13.9 Section 13.9 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY PROGRAM FRAUD CIVIL REMEDIES § 13.9 Answer. (a) The Defendant may request a hearing by serving an answer on the Reviewing Official within 30 days of service...

  8. 6 CFR 13.9 - Answer.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 6 Domestic Security 1 2012-01-01 2012-01-01 false Answer. 13.9 Section 13.9 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY PROGRAM FRAUD CIVIL REMEDIES § 13.9 Answer. (a) The Defendant may request a hearing by serving an answer on the Reviewing Official within 30 days of service...

  9. 49 CFR 37.139 - Plan contents.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Administration joint planning regulation (49 CFR part 613 and 23 CFR part 450). In a service area which is... 49 Transportation 1 2011-10-01 2011-10-01 false Plan contents. 37.139 Section 37.139... DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.139 Plan contents. Each plan...

  10. 25 CFR 139.3 - Payments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Payments. 139.3 Section 139.3 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES REIMBURSEMENT OF CONSTRUCTION COSTS, WAPATO-SATUS UNIT, WAPATO INDIAN IRRIGATION PROJECT, WASHINGTON § 139.3 Payments. Payments are due on December 31...

  11. 49 CFR 37.139 - Plan contents.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Administration joint planning regulation (49 CFR part 613 and 23 CFR part 450). In a service area which is... 49 Transportation 1 2014-10-01 2014-10-01 false Plan contents. 37.139 Section 37.139... DISABILITIES (ADA) Paratransit as a Complement to Fixed Route Service § 37.139 Plan contents. Each plan...

  12. 29 CFR 780.139 - Pea vining.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Pea vining. 780.139 Section 780.139 Labor Regulations... âsuch Farming Operationâ-of the Farmer § 780.139 Pea vining. Vining employees of a pea vinery located on a farm, who vine only the peas grown on that particular farm, are engaged in agriculture. If...

  13. Pharmacological potential of cerium oxidenanoparticles

    NASA Astrophysics Data System (ADS)

    Celardo, Ivana; Pedersen, Jens Z.; Traversa, Enrico; Ghibelli, Lina

    2011-04-01

    Nanotechnology promises a revolution in pharmacology to improve or create ex novo therapies. Cerium oxidenanoparticles (nanoceria), well-known as catalysts, possess an astonishing pharmacological potential due to their antioxidant properties, deriving from a fraction of Ce3+ ions present in CeO2. These defects, compensated by oxygen vacancies, are enriched at the surface and therefore in nanosized particles. Reactions involving redox cycles between the Ce3+ and Ce4+oxidation states allow nanoceria to react catalytically with superoxide and hydrogen peroxide, mimicking the behavior of two key antioxidant enzymes, superoxide dismutase and catalase, potentially abating all noxious intracellularreactive oxygen species (ROS) via a self-regenerating mechanism. Hence nanoceria, apparently well tolerated by the organism, might fight chronic inflammation and the pathologies associated with oxidative stress, which include cancer and neurodegeneration. Here we review the biological effects of nanoceria as they emerge from in vitro and in vivo studies, considering biocompatibility and the peculiar antioxidant mechanisms.

  14. Cerium anomaly at microscale in fossils.

    PubMed

    Gueriau, Pierre; Mocuta, Cristian; Bertrand, Loïc

    2015-09-01

    Patterns in rare earth element (REE) concentrations are essential instruments to assess geochemical processes in Earth and environmental sciences. Excursions in the "cerium anomaly" are widely used to inform on past redox conditions in sediments. This proxy resources to the specificity of cerium to adopt both the +III and +IV oxidation states, while most rare earths are purely trivalent and share very similar reactivity and transport properties. In practical terms, the level of cerium anomaly is established through elemental point quantification and profiling. All these models rely on a supposed homogeneity of the cerium oxidation state within the samples. However, this has never been demonstrated, whereas the cerium concentration can significantly vary within a sample, as shown for fossils, which would vastly complicate interpretation of REE patterns. Here, we report direct micrometric mapping of Ce speciation through synchrotron X-ray absorption spectroscopy and production of local rare earth patterns in paleontological fossil tissues through X-ray fluorescence mapping. The sensitivity of the approach is demonstrated on well-preserved fishes and crustaceans from the Late Cretaceous (ca. 95 million years (Myr) old). The presence of Ce under the +IV form within the fossil tissues is attributed to slightly oxidative local conditions of burial and agrees well with the limited negative cerium anomaly observed in REE patterns. The [Ce(IV)]/[Ce(tot)] ratio appears remarkably stable at the microscale within each fossil and is similar between fossils from the locality. Speciation maps were obtained from an original combination of synchrotron microbeam X-ray fluorescence, absorption spectroscopy, and diffraction, together with light and electron microscopy. This work also highlights the need for more systematic studies of cerium geochemistry at the microscale in paleontological contexts, in particular across fossil histologies.

  15. Cerium anomaly at microscale in fossils.

    PubMed

    Gueriau, Pierre; Mocuta, Cristian; Bertrand, Loïc

    2015-09-01

    Patterns in rare earth element (REE) concentrations are essential instruments to assess geochemical processes in Earth and environmental sciences. Excursions in the "cerium anomaly" are widely used to inform on past redox conditions in sediments. This proxy resources to the specificity of cerium to adopt both the +III and +IV oxidation states, while most rare earths are purely trivalent and share very similar reactivity and transport properties. In practical terms, the level of cerium anomaly is established through elemental point quantification and profiling. All these models rely on a supposed homogeneity of the cerium oxidation state within the samples. However, this has never been demonstrated, whereas the cerium concentration can significantly vary within a sample, as shown for fossils, which would vastly complicate interpretation of REE patterns. Here, we report direct micrometric mapping of Ce speciation through synchrotron X-ray absorption spectroscopy and production of local rare earth patterns in paleontological fossil tissues through X-ray fluorescence mapping. The sensitivity of the approach is demonstrated on well-preserved fishes and crustaceans from the Late Cretaceous (ca. 95 million years (Myr) old). The presence of Ce under the +IV form within the fossil tissues is attributed to slightly oxidative local conditions of burial and agrees well with the limited negative cerium anomaly observed in REE patterns. The [Ce(IV)]/[Ce(tot)] ratio appears remarkably stable at the microscale within each fossil and is similar between fossils from the locality. Speciation maps were obtained from an original combination of synchrotron microbeam X-ray fluorescence, absorption spectroscopy, and diffraction, together with light and electron microscopy. This work also highlights the need for more systematic studies of cerium geochemistry at the microscale in paleontological contexts, in particular across fossil histologies. PMID:26239283

  16. α-Radioactivity of cerium-142

    USGS Publications Warehouse

    Senftle, F.E.; Stern, T.W.; Alekna, V.P.

    1959-01-01

    JOHNSON AND NIER1 have measured the atomic masses of some of the rare-earth isotopes and have shown that the mass difference cerium-142—(barium-138 + helium-4) is equivalent to 1.68 ± 0.10 MeV. Similar results for the naturally occurring samarium and neodymium isotopes show that the α-active isotope of each element is the one having the largest possible decay energy. Rasmussen and others2 suggest that the two or three neutrons just beyond the closed shell of 82 neutrons have decreased binding energies and hence the α-energy has a maximum about 84 neutrons. Johnson and Nier suggest that the α-decay of cerium-142 may take place with enough energy to be experimentally observable. Porschen and Riezler3 examined a sample of un-enriched cerium ammonium citrate using nuclear track plates sensitive to α-particles. No α-activity was observed after a 30-day exposure of 1.2 mgm. of the cerium salt. In 1957 Riezler and Kauw4 reported an alpha activity for an enriched sample of cerium-142. From their results they calculated a half-life of 5.1 × 1015 years with an uncertainty factor of 2.

  17. Nanocrystalline cerium oxide materials for solid fuel cell systems

    SciTech Connect

    Brinkman, Kyle S

    2015-05-05

    Disclosed are solid fuel cells, including solid oxide fuel cells and PEM fuel cells that include nanocrystalline cerium oxide materials as a component of the fuel cells. A solid oxide fuel cell can include nanocrystalline cerium oxide as a cathode component and microcrystalline cerium oxide as an electrolyte component, which can prevent mechanical failure and interdiffusion common in other fuel cells. A solid oxide fuel cell can also include nanocrystalline cerium oxide in the anode. A PEM fuel cell can include cerium oxide as a catalyst support in the cathode and optionally also in the anode.

  18. Divalent fluoride doped cerium fluoride scintillator

    DOEpatents

    Anderson, David F.; Sparrow, Robert W.

    1991-01-01

    The use of divalent fluoride dopants in scintillator materials comprising cerium fluoride is disclosed. The preferred divalent fluoride dopants are calcium fluoride, strontium fluoride, and barium fluoride. The preferred amount of divalent fluoride dopant is less than about two percent by weight of the total scintillator. Cerium fluoride scintillator crystals grown with the addition of a divalent fluoride have exhibited better transmissions and higher light outputs than crystals grown without the addition of such dopants. These scintillators are useful in radiation detection and monitoring applications, and are particularly well suited for high-rate applications such as positron emission tomography (PET).

  19. 14 CFR 139.113 - Deviations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Deviations. 139.113 Section 139.113 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... life or property, the certificate holder may deviate from any requirement of subpart D of this part,...

  20. 14 CFR 139.201 - General requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... authorized by the Administrator; (3) Is in printed form and signed by the certificate holder acknowledging... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false General requirements. 139.201 Section 139... the Administrator; and (3) Furnish the applicable portions of the approved Airport...

  1. 22 CFR 139.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Definitions. 139.2 Section 139.2 Foreign... Definitions. The following definitions apply to this part: Accompanying family members means the spouse and... Department to carry out the Department's responsibilities for the day-to-day management of the...

  2. 14 CFR 139.5 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Definitions. 139.5 Section 139.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... that is conducted as a supplemental operation under 14 CFR part 121 or public charter operations...

  3. Cerium migration during PEM fuel cell accelerated stress testing

    SciTech Connect

    Baker, Andrew M.; Mukundan, Rangachary; Borup, Rodney L.; Spernjak, Dusan; Judge, Elizabeth J.; Advani, Suresh G.; Prasad, Ajay K.

    2016-01-01

    Cerium is a radical scavenger which improves polymer electrolyte membrane (PEM) fuel cell durability. During operation, however, cerium rapidly migrates in the PEM and into the catalyst layers (CLs). In this work, membrane electrode assemblies (MEAs) were subjected to accelerated stress tests (ASTs) under different humidity conditions. Cerium migration was characterized in the MEAs after ASTs using X-ray fluorescence. During fully humidified operation, water flux from cell inlet to outlet generated in-plane cerium gradients. Conversely, cerium profiles were flat during low humidity operation, where in-plane water flux was negligible, however, migration from the PEM into the CLs was enhanced. Humidity cycling resulted in both in-plane cerium gradients due to water flux during the hydration component of the cycle, and significant migration into the CLs. Fluoride and cerium emissions into effluent cell waters were measured during ASTs and correlated, which signifies that ionomer degradation products serve as possible counter-ions for cerium emissions. Fluoride emission rates were also correlated to final PEM cerium contents, which indicates that PEM degradation and cerium migration are coupled. Lastly, it is proposed that cerium migrates from the PEM due to humidification conditions and degradation, and is subsequently stabilized in the CLs by carbon catalyst supports.

  4. Cerium migration during PEM fuel cell accelerated stress testing

    DOE PAGES

    Baker, Andrew M.; Mukundan, Rangachary; Borup, Rodney L.; Spernjak, Dusan; Judge, Elizabeth J.; Advani, Suresh G.; Prasad, Ajay K.

    2016-01-01

    Cerium is a radical scavenger which improves polymer electrolyte membrane (PEM) fuel cell durability. During operation, however, cerium rapidly migrates in the PEM and into the catalyst layers (CLs). In this work, membrane electrode assemblies (MEAs) were subjected to accelerated stress tests (ASTs) under different humidity conditions. Cerium migration was characterized in the MEAs after ASTs using X-ray fluorescence. During fully humidified operation, water flux from cell inlet to outlet generated in-plane cerium gradients. Conversely, cerium profiles were flat during low humidity operation, where in-plane water flux was negligible, however, migration from the PEM into the CLs was enhanced. Humiditymore » cycling resulted in both in-plane cerium gradients due to water flux during the hydration component of the cycle, and significant migration into the CLs. Fluoride and cerium emissions into effluent cell waters were measured during ASTs and correlated, which signifies that ionomer degradation products serve as possible counter-ions for cerium emissions. Fluoride emission rates were also correlated to final PEM cerium contents, which indicates that PEM degradation and cerium migration are coupled. Lastly, it is proposed that cerium migrates from the PEM due to humidification conditions and degradation, and is subsequently stabilized in the CLs by carbon catalyst supports.« less

  5. An investigation of the continuum resonance effect in cerium and cerium oxide

    NASA Astrophysics Data System (ADS)

    Roberts, Mark W.

    1998-10-01

    Large x-ray emission resonances associated with the M shell in cerium and cerium oxide were investigated. The device used in this investigation consisted of an energy dispersive x-ray detector and a double-pass cylindrical mirror electron analyzer within an ultra-high vacuum system. Observations were made of the x-ray and electron emissions from samples bombarded by mono-energetic electrons from an electron gun. The x-ray and electron data were recorded with the system pressure in the low 10-9 torr range. X-ray data were obtained using incident electron energies from 865 eV to 925 eV; the binding energies of the cerium M5 and M4 subshells and the x-ray continuum resonances are contained within this energy range. The x- ray detector was set to count x-rays in a fixed energy window 120 eV wide, centered on 900 eV. Differentiated electron spectra from the samples were recorded using a lock-in amplifier. Vacuum evaporation and condensation were used to deposit cerium metal samples onto a wheel which was then rotated to position a given sample in front of the electron gun. Cerium oxide samples were obtained by exposing cerium metal deposits to room air at atmospheric pressure and then repumping the system. The x-ray yield spectra from the cerium and cerium oxide samples show large resonances for incident electron energies near the M5 and M4 level ionization energies. There are no features in the electron spectra which correspond to the large resonances observed in the x-ray yield spectra. These findings are in agreement with results previously obtained by Chamberlain et al. and by Mason. The maxima in the x-ray resonances for cerium oxide occur at slightly lower incident electron energy than those for cerium metal. There is also a large increase in the intensity of the x-ray continuum resonance yield in cerium oxide above that in the metal. Possible explanations for these observations are presented.

  6. Uptake and accumulation of bulk and nanosized cerium oxide particles and ionic cerium by radish (Raphanus sativus L.).

    PubMed

    Zhang, Weilan; Ebbs, Stephen D; Musante, Craig; White, Jason C; Gao, Cunmei; Ma, Xingmao

    2015-01-21

    The potential toxicity and accumulation of engineered nanomaterials (ENMs) in agricultural crops has become an area of great concern and intense investigation. Interestingly, although below-ground vegetables are most likely to accumulate the highest concentrations of ENMs, little work has been done investigating the potential uptake and accumulation of ENMs for this plant group. The overall objective of this study was to evaluate how different forms of cerium (bulk cerium oxide, cerium oxide nanoparticles, and the cerium ion) affected the growth of radish (Raphanus sativus L.) and accumulation of cerium in radish tissues. Ionic cerium (Ce(3+)) had a negative effect on radish growth at 10 mg CeCl3/L, whereas bulk cerium oxide (CeO2) enhanced plant biomass at the same concentration. Treatment with 10 mg/L cerium oxide nanoparticles (CeO2 NPs) had no significant effect on radish growth. Exposure to all forms of cerium resulted in the accumulation of this element in radish tissues, including the edible storage root. However, the accumulation patterns and their effect on plant growth and physiological processes varied with the characteristics of cerium. This study provides a critical frame of reference on the effects of CeO2 NPs versus their bulk and ionic counterparts on radish growth.

  7. Synthesis of Cerium-Doped Titania Nanoparticles and Nanotubes.

    PubMed

    Cao, Wei; Suzuki, Takuya; Elsayed-Ali, Hani E; Abdel-Fattah, Tarek M

    2015-03-01

    Cerium-doped titania nanoparticles and nanotubes were synthesized via hydrothermal processes. X-Ray Diffraction revealed that cerium-doped titania nanoparticles have an anatase crystal structure, while cerium-doped titania nanotubes have an H2Ti3O7-type structure. Scanning electron microscopy and high resolution transmission electron microscopy showed that both types of titania are well crystallized with relatively uniform size distribution. The photocatalytic degradation of methylthioninium chloride known as methylene blue dye was tested and both cerium-doped titania nanoparticles and nanotubes. The preliminary photocatalytic degradation of Methylene Blue data showed significantly improved visible light photocatalytic activities as compared to commercial titania powders.

  8. Antimony promoted bismuth cerium molybdate catalysts

    SciTech Connect

    Brazdil, J.F.; Glaeser, L.C.; Grasselli, R.K.

    1990-05-01

    This patent describes an improvement in antimony-promoted bismuth cerium molybdate whereby the tendency of the catalyst to lose efectiveness over time is significantly reduced. This patent describes new catalysts which are also useful in other oxidation-type reactions such as the oxidation of acrolein and methacrolein to produce the corresponding unsaturated aldehydes and acids and the oxydehydrogenation of various olefins such as isoamylenes to produce the corresponding diolefins such as isoprene.

  9. Atomic Transition Probabilities for Neutral Cerium

    NASA Astrophysics Data System (ADS)

    Lawler, J. E.; den Hartog, E. A.; Wood, M. P.; Nitz, D. E.; Chisholm, J.; Sobeck, J.

    2009-10-01

    The spectra of neutral cerium (Ce I) and singly ionized cerium (Ce II) are more complex than spectra of other rare earth species. The resulting high density of lines in the visible makes Ce ideal for use in metal halide (MH) High Intensity Discharge (HID) lamps. Inclusion of cerium-iodide in a lamp dose can improve both the Color Rendering Index and luminous efficacy of a MH-HID lamp. Basic spectroscopic data including absolute atomic transition probabilities for Ce I and Ce II are needed for diagnosing and modeling these MH-HID lamps. Recent work on Ce II [1] is now being augmented with similar work on Ce I. Radiative lifetimes from laser induced fluorescence measurements [2] on neutral Ce are being combined with emission branching fractions from spectra recorded using a Fourier transform spectrometer. A total of 14 high resolution spectra are being analyzed to determine branching fractions for 2000 to 3000 lines from 153 upper levels in neutral Ce. Representative data samples and progress to date will be presented. [4pt] [1] J. E. Lawler, C. Sneden, J. J. Cowan, I. I. Ivans, and E. A. Den Hartog, Astrophys. J. Suppl. Ser. 182, 51-79 (2009). [0pt] [2] E. A. Den Hartog, K. P. Buettner, and J. E. Lawler, J. Phys. B: Atomic, Molecular & Optical Physics 42, 085006 (7pp) (2009).

  10. Local Structure of Cerium in Aluminophosphate and Silicophosphate Glasses

    SciTech Connect

    Rygel, Jennifer L.; Chen, Yongsheng; Pantano, Carlo G.; Shibata, Tomohiro; Du, Jincheng; Kokou, Leopold; Woodman, Robert; Belcher, James

    2011-09-20

    The local structure of cerium in two systematic compositional series of glasses, nominally CeP{sub 3}O{sub 9}-AlP{sub 3}O{sub 9} and CeP{sub 3}O{sub 9}-SiP{sub 2}O{sub 7}, was interrogated using X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) spectroscopy. XPS revealed that, for glasses melted in air, {>=}95% of cerium ions are Ce{sup 3+}. This was independently confirmed using X-ray absorption near edge spectroscopy (XANES). Ce K-edge extended X-ray absorption fine structure (EXAFS) has been used to determine the local structure of Ce{sup 3+}. Near the metaphosphate composition, cerium was found to have an average cerium coordination number of {approx}7.0 and an average cerium-oxygen bond length of 2.41 {angstrom}. The average cerium coordination number and average cerium-oxygen bond distance were found to increase with decreasing cerium concentration in both compositional series. Rare-earth clustering is suggested based on numerical calculations for glasses containing {>=}14 and {>=}15 mol% Ce{sub 2}O{sub 3} for the aluminophosphate and silicophosphate series, respectively.

  11. Study of the cerium(IV)-picrate system in acetonitrile.

    PubMed

    Kratochvil, B; Tipler, M; McKay, B

    1966-07-01

    A potentiometric and spectrophotometric study has been made of the reaction between hexanitratocerate and picrate in dry acetonitrile. Several cerium(IV)-picrate complexes are formed; the formation constant for the first is estimated to be 4 from spectrophotometric measurements. The catalytic effect of picrate on hydroquinone oxidation by nitratocerate is postulated to be due to more rapid electron transfer by cerium picrate complexes.

  12. RECOVERY OF Pu FROM CERIUM TRIFLUORIDE BY FLUORINATION

    DOEpatents

    Brown, H.S.; Bohlmann, E.G.

    1959-02-10

    An improved process is prcsented for selectively recovering plutonium from a solution containing fission products comprising precipitating cerium trifluoride in the solution for effccting carrier precipitation of plutonium. The resulting carrier precipitate is dried and subjected to fluorination at about 600 C. The plutonium forms a volatile fiuoridc and is so separated from the nonvolatile cerium fluoride.

  13. Cerium migration during PEM fuel cell assembly and operation

    SciTech Connect

    Baker, Andrew M.; Torraco, Dennis; Judge, Elizabeth J.; Spernjak, Dusan; Mukundan, Rangachary; Borup, Rod L.; Advani, Suresh G.; Prasad, Ajay K.

    2015-10-02

    Cerium migration between PEM fuel cell components is influenced by potential-driven mobility, ionic diffusion, and gradients in water content. These factors were investigated in ex situ experiments and in operating fuel cells. Potential-induced migration was measured ex situ in hydrated window cells. Cerium-containing MEAs were also fabricated and tested under ASTs. MEA disassembly and subsequent XRF analysis were used to observe rapid cerium migration during cell assembly and operation. During MEA hot pressing, humidification, and low RH operation at OCV, ionic diffusion causes uniform migration from the membrane into the catalyst layers. During high RH operation at OCV, in-plane cerium gradients arise due to variations in water content. These gradients may diminish the scavenging efficacy of cerium by reducing its proximity to generated radicals.

  14. Cerium migration during PEM fuel cell assembly and operation

    SciTech Connect

    Baker, Andrew M.; Torraco, Dennis; Judge, Elizabeth J.; Spernjak, Dusan; Mukundan, Rangachary; Borup, Rod L.; Advani, Suresh G.; Prasad, Ajay K.

    2015-09-14

    Cerium migration between PEM fuel cell components is influenced by potential-driven mobility, ionic diffusion, and gradients in water content. These factors were investigated in ex situ experiments and in operating fuel cells. Potential-induced migration was measured ex situ in hydrated window cells. Cerium-containing MEAs were also fabricated and tested under ASTs. MEA disassembly and subsequent XRF analysis were used to observe rapid cerium migration during cell assembly and operation. During MEA hot pressing, humidification, and low RH operation at OCV, ionic diffusion causes uniform migration from the membrane into the catalyst layers. During high RH operation at OCV, in-plane cerium gradients arise due to variations in water content. These gradients may diminish the scavenging efficacy of cerium by reducing its proximity to generated radicals.

  15. Ultrathin, epitaxial cerium dioxide on silicon

    NASA Astrophysics Data System (ADS)

    Flege, Jan Ingo; Kaemena, Björn; Höcker, Jan; Bertram, Florian; Wollschläger, Joachim; Schmidt, Thomas; Falta, Jens

    2014-03-01

    It is shown that ultrathin, highly ordered, continuous films of cerium dioxide may be prepared on silicon following substrate prepassivation using an atomic layer of chlorine. The as-deposited, few-nanometer-thin Ce2O3 film may very effectively be converted at room temperature to almost fully oxidized CeO2 by simple exposure to air, as demonstrated by hard X-ray photoemission spectroscopy and X-ray diffraction. This post-oxidation process essentially results in a negligible loss in film crystallinity and interface abruptness.

  16. Ultrathin, epitaxial cerium dioxide on silicon

    SciTech Connect

    Flege, Jan Ingo Kaemena, Björn; Höcker, Jan; Schmidt, Thomas; Falta, Jens; Bertram, Florian; Wollschläger, Joachim

    2014-03-31

    It is shown that ultrathin, highly ordered, continuous films of cerium dioxide may be prepared on silicon following substrate prepassivation using an atomic layer of chlorine. The as-deposited, few-nanometer-thin Ce{sub 2}O{sub 3} film may very effectively be converted at room temperature to almost fully oxidized CeO{sub 2} by simple exposure to air, as demonstrated by hard X-ray photoemission spectroscopy and X-ray diffraction. This post-oxidation process essentially results in a negligible loss in film crystallinity and interface abruptness.

  17. Photodissociation of Cerium Oxide Nanocluster Cations.

    PubMed

    Akin, S T; Ard, S G; Dye, B E; Schaefer, H F; Duncan, M A

    2016-04-21

    Cerium oxide cluster cations, CexOy(+), are produced via laser vaporization in a pulsed nozzle source and detected with time-of-flight mass spectrometry. The mass spectrum displays a strongly preferred oxide stoichiometry for each cluster with a specific number of metal atoms x, with x ≤ y. Specifically, the most prominent clusters correspond to the formula CeO(CeO2)n(+). The cluster cations are mass selected and photodissociated with a Nd:YAG laser at either 532 or 355 nm. The prominent clusters dissociate to produce smaller species also having a similar CeO(CeO2)n(+) formula, always with apparent leaving groups of (CeO2). The production of CeO(CeO2)n(+) from the dissociation of many cluster sizes establishes the relative stability of these clusters. Furthermore, the consistent loss of neutral CeO2 shows that the smallest neutral clusters adopt the same oxidation state (IV) as the most common form of bulk cerium oxide. Clusters with higher oxygen content than the CeO(CeO2)n(+) masses are present with much lower abundance. These species dissociate by the loss of O2, leaving surviving clusters with the CeO(CeO2)n(+) formula. Density functional theory calculations on these clusters suggest structures composed of stable CeO(CeO2)n(+) cores with excess oxygen bound to the surface as a superoxide unit (O2(-)). PMID:27035210

  18. The surface chemistry of cerium oxide

    SciTech Connect

    Mullins, David R.

    2015-01-29

    Our review covers the structure of, and chemical reactions on, well-defined cerium oxide surfaces. Ceria, or mixed oxides containing ceria, are critical components in automotive three-way catalysts due to their well-known oxygen storage capacity. Ceria is also emerging as an important material in a number of other catalytic processes, particularly those involving organic oxygenates and the water–gas shift reaction. Ceria's acid–base properties, and thus its catalytic behavior, are closely related to its surface structure where different oxygen anion and cerium cation environments are present on the low-index structural faces. The actual structure of these various faces has been the focus of a number of theoretical and experimental investigations. Ceria is also easily reducible from CeO2 to CeO2-X. The presence of oxygen vacancies on the surface often dramatically alters the adsorption and subsequent reactions of various adsorbates, either on a clean surface or on metal particles supported on the surface. We conducted surface science studies on the surfaces of thin-films rather than on the surfaces of bulk single crystal oxides. The growth, characterization and properties of these thin-films are also examined.

  19. The surface chemistry of cerium oxide

    DOE PAGES

    Mullins, David R.

    2015-01-29

    Our review covers the structure of, and chemical reactions on, well-defined cerium oxide surfaces. Ceria, or mixed oxides containing ceria, are critical components in automotive three-way catalysts due to their well-known oxygen storage capacity. Ceria is also emerging as an important material in a number of other catalytic processes, particularly those involving organic oxygenates and the water–gas shift reaction. Ceria's acid–base properties, and thus its catalytic behavior, are closely related to its surface structure where different oxygen anion and cerium cation environments are present on the low-index structural faces. The actual structure of these various faces has been the focusmore » of a number of theoretical and experimental investigations. Ceria is also easily reducible from CeO2 to CeO2-X. The presence of oxygen vacancies on the surface often dramatically alters the adsorption and subsequent reactions of various adsorbates, either on a clean surface or on metal particles supported on the surface. We conducted surface science studies on the surfaces of thin-films rather than on the surfaces of bulk single crystal oxides. The growth, characterization and properties of these thin-films are also examined.« less

  20. The surface chemistry of cerium oxide

    NASA Astrophysics Data System (ADS)

    Mullins, David R.

    2015-03-01

    This review covers the structure of, and chemical reactions on, well-defined cerium oxide surfaces. Ceria, or mixed oxides containing ceria, are critical components in automotive three-way catalysts due to their well-known oxygen storage capacity. Ceria is also emerging as an important material in a number of other catalytic processes, particularly those involving organic oxygenates and the water-gas shift reaction. Ceria's acid-base properties, and thus its catalytic behavior, are closely related to its surface structure where different oxygen anion and cerium cation environments are present on the low-index structural faces. The actual structure of these various faces has been the focus of a number of theoretical and experimental investigations. Ceria is also easily reducible from CeO2 to CeO2-X. The presence of oxygen vacancies on the surface often dramatically alters the adsorption and subsequent reactions of various adsorbates, either on a clean surface or on metal particles supported on the surface. Most surface science studies have been conducted on the surfaces of thin-films rather than on the surfaces of bulk single crystal oxides. The growth, characterization and properties of these thin-films are also examined.

  1. Microstructure of surface cerium hydride growth sites

    SciTech Connect

    Brierley, Martin; Knowles, John; Montgomery, Neil; Preuss, Michael

    2014-05-15

    Samples of cerium were exposed to hydrogen under controlled conditions causing cerium hydride sites to nucleate and grow on the surface. The hydriding rate was measured in situ, and the hydrides were characterised using secondary ion mass spectrometry, scanning electron microscopy, and optical microscopy. The results show that the hydriding rate proceeded more quickly than earlier studies. Characterisation confirmed that the hydrogen is confined to the sites. The morphology of the hydrides was confirmed to be oblate, and stressed material was observed surrounding the hydride, in a number of cases lathlike features were observed surrounding the hydride sites laterally with cracking in the surface oxide above them. It is proposed that during growth the increased lattice parameter of the CeH{sub 2} induces a lateral compressive stress around the hydride, which relieves by the ca. 16% volume collapse of the γ-Ce to α-Ce pressure induced phase transition. Cracking of the surface oxide above the laths reduces the diffusion barrier to hydrogen reaching the metal/oxide interface surrounding the hydride site and contributes to the anisotropic growth of the hydrides.

  2. Optical properties of cerium-codoped high power laser fibers

    NASA Astrophysics Data System (ADS)

    Unger, S.; Schwuchow, A.; Jetschke, S.; Grimm, S.; Scheffel, A.; Kirchhof, J.

    2013-03-01

    The photodarkening resistivity of ytterbium doped alumosilicate fibers can be remarkably improved by cerium codoping. Here we report on systematical investigations of the influence of cerium on an optimized fiber design. Fibers with different ytterbium, aluminium and cerium contents have been prepared both under reducing and oxydizing conditions and characterized concerning refractive index, absorption and emission from UV to NIR. Typical spectral features in the UV and visible range have been analysed with respect to the ratio of Ce3+ / Ce4+. Photodarkening tests have been accomplished in order to correlate the power stability with the Ce content and valency state.

  3. Antibacterial activity of cerium colloids against opportunistic microorganisms in vitro.

    PubMed

    Babenko, L P; Zholobak, N M; Shcherbakov, A B; Voychuk, S I; Lazarenko, L M; Spivak, M Ya

    2012-01-01

    The CeO2 sol with the size of nanoparticles 2-4 nm has been synthesized. It has been determined that the synthesized nanocrystalline cerium has antibacterial activity in vitro against different groups of opportunistic microorganisms: clinical strains of Escherichia coli, Staphylococcus aureus and Candida albicans. The rate of viability depression of test-cultures depends on the concentration of cerium dioxide nanoparticles and time of incubation. It is shown that the sol interacts with the bacterial cell surface. It is suggested that the observed differences of antibacterial action of nanocrystalline cerium dioxide can be related to the structural characteristics of the cell surface.

  4. High spin states in {sup 139}Pm

    SciTech Connect

    Dhal, A.; Sinha, R. K.; Chaturvedi, L.; Agarwal, P.; Kumar, S.; Jain, A. K.; Kumar, R.; Govil, I. M.; Mukhopadhyay, S.; Chakraborty, A.; Krishichayan; Ray, S.; Ghugre, S. S.; Sinha, A. K.; Kumar, R.; Singh, R. P.; Muralithar, S.; Bhowmik, R. K.; Pancholi, S. C.; Gupta, J. B.

    2009-07-15

    The odd mass nucleus {sup 139}Pm has been studied to high spins through the {sup 116}Cd({sup 27}Al,4n){sup 139}Pm reaction at an incident beam energy of 120 MeV. The de-exciting {gamma}-rays were detected using an array of 12 Compton suppressed Ge detectors. A total of 46 new levels have been proposed in the present work as a result of the observation of 60 new {gamma}-rays. Four new bands including a {delta}J=1 sequence have been identified and all the earlier reported bands, other than the yrast band, have been extended to higher spins and excitation energy. The spin assignments for most of the newly reported levels have been made using the observed coincidence angular anisotropy. Tilted axis cranking calculations support the interpretation of two of the observed magnetic dipole sequences as examples of magnetic rotational bands.

  5. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Whole wheat macaroni products. 139.138 Section 139... and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the...)(3), and (g), except that: (1) Whole wheat flour or whole durum wheat flour or both are used as...

  6. 21 CFR 139.180 - Wheat and soy noodle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Wheat and soy noodle products. 139.180 Section 139... and Noodle Products § 139.180 Wheat and soy noodle products. (a) Wheat and soy noodle products are the... wheat and soy ingredients used (the soy flour used is made from heat-processed, dehulled soybeans,...

  7. 21 CFR 139.180 - Wheat and soy noodle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Wheat and soy noodle products. 139.180 Section 139... and Noodle Products § 139.180 Wheat and soy noodle products. (a) Wheat and soy noodle products are the... wheat and soy ingredients used (the soy flour used is made from heat-processed, dehulled soybeans,...

  8. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Whole wheat macaroni products. 139.138 Section 139... and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the...)(3), and (g), except that: (1) Whole wheat flour or whole durum wheat flour or both are used as...

  9. 21 CFR 139.180 - Wheat and soy noodle products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Wheat and soy noodle products. 139.180 Section 139... and Noodle Products § 139.180 Wheat and soy noodle products. (a) Wheat and soy noodle products are the... wheat and soy ingredients used (the soy flour used is made from heat-processed, dehulled soybeans,...

  10. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Whole wheat macaroni products. 139.138 Section 139... and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the...)(3), and (g), except that: (1) Whole wheat flour or whole durum wheat flour or both are used as...

  11. 21 CFR 139.180 - Wheat and soy noodle products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Wheat and soy noodle products. 139.180 Section 139... and Noodle Products § 139.180 Wheat and soy noodle products. (a) Wheat and soy noodle products are the... wheat and soy ingredients used (the soy flour used is made from heat-processed, dehulled soybeans,...

  12. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Whole wheat macaroni products. 139.138 Section 139... and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the...)(3), and (g), except that: (1) Whole wheat flour or whole durum wheat flour or both are used as...

  13. 21 CFR 139.138 - Whole wheat macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Whole wheat macaroni products. 139.138 Section 139... and Noodle Products § 139.138 Whole wheat macaroni products. (a) Whole wheat macaroni products are the...)(3), and (g), except that: (1) Whole wheat flour or whole durum wheat flour or both are used as...

  14. 21 CFR 139.180 - Wheat and soy noodle products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Wheat and soy noodle products. 139.180 Section 139... and Noodle Products § 139.180 Wheat and soy noodle products. (a) Wheat and soy noodle products are the... wheat and soy ingredients used (the soy flour used is made from heat-processed, dehulled soybeans,...

  15. 50 CFR 550.131-550.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 11 2013-10-01 2013-10-01 false 550.131-550.139 Section 550.131-550.139 Wildlife and Fisheries MARINE MAMMAL COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY MARINE MAMMAL COMMISSION §§ 550.131-550.139...

  16. 50 CFR 550.131-550.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 11 2014-10-01 2014-10-01 false 550.131-550.139 Section 550.131-550.139 Wildlife and Fisheries MARINE MAMMAL COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY MARINE MAMMAL COMMISSION §§ 550.131-550.139...

  17. 50 CFR 550.131-550.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 11 2012-10-01 2012-10-01 false 550.131-550.139 Section 550.131-550.139 Wildlife and Fisheries MARINE MAMMAL COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY MARINE MAMMAL COMMISSION §§ 550.131-550.139...

  18. 50 CFR 550.131-550.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false 550.131-550.139 Section 550.131-550.139 Wildlife and Fisheries MARINE MAMMAL COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY MARINE MAMMAL COMMISSION §§ 550.131-550.139...

  19. 50 CFR 550.131-550.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false 550.131-550.139 Section 550.131-550.139 Wildlife and Fisheries MARINE MAMMAL COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY MARINE MAMMAL COMMISSION §§ 550.131-550.139...

  20. 44 CFR 16.131-16.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false 16.131-16.139 Section 16.131-16.139 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... ACTIVITIES CONDUCTED BY THE FEDERAL EMERGENCY MANAGEMENT AGENCY §§ 16.131-16.139...

  1. 10 CFR 1.39 - Office of Human Resources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Office of Human Resources. 1.39 Section 1.39 Energy... § 1.39 Office of Human Resources. The Office of Human Resources— (a) Plans and implements NRC policies... agency's human resources; (b) Provides labor relations and personnel policy guidance and...

  2. 10 CFR 1.39 - Office of Human Resources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Office of Human Resources. 1.39 Section 1.39 Energy... § 1.39 Office of Human Resources. The Office of Human Resources— (a) Plans and implements NRC policies... agency's human resources; (b) Provides labor relations and personnel policy guidance and...

  3. 10 CFR 1.39 - Office of Human Resources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Office of Human Resources. 1.39 Section 1.39 Energy... § 1.39 Office of Human Resources. The Office of Human Resources— (a) Plans and implements NRC policies... agency's human resources; (b) Provides labor relations and personnel policy guidance and...

  4. 29 CFR 2205.131-2205.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 9 2011-07-01 2011-07-01 false 2205.131-2205.139 Section 2205.131-2205.139 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH REVIEW COMMISSION ENFORCEMENT OF... REVIEW COMMISSION §§ 2205.131-2205.139...

  5. 29 CFR 2205.131-2205.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false 2205.131-2205.139 Section 2205.131-2205.139 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH REVIEW COMMISSION ENFORCEMENT OF... REVIEW COMMISSION §§ 2205.131-2205.139...

  6. 41 CFR 51-10.131-51-10.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true 51-10.131-51-10.139 Section 51-10.131-51-10.139 Public Contracts and Property Management Other Provisions Relating to Public... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED §§ 51-10.131—51-10.139...

  7. 41 CFR 51-10.131-51-10.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 1 2014-07-01 2014-07-01 false 51-10.131-51-10.139 Section 51-10.131-51-10.139 Public Contracts and Property Management Other Provisions Relating to Public... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED §§ 51-10.131—51-10.139...

  8. 41 CFR 51-10.131-51-10.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 1 2013-07-01 2013-07-01 false 51-10.131-51-10.139 Section 51-10.131-51-10.139 Public Contracts and Property Management Other Provisions Relating to Public... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED §§ 51-10.131—51-10.139...

  9. 41 CFR 51-10.131-51-10.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 1 2012-07-01 2009-07-01 true 51-10.131-51-10.139 Section 51-10.131-51-10.139 Public Contracts and Property Management Other Provisions Relating to Public... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED §§ 51-10.131—51-10.139...

  10. 41 CFR 51-10.131-51-10.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 1 2011-07-01 2009-07-01 true 51-10.131-51-10.139 Section 51-10.131-51-10.139 Public Contracts and Property Management Other Provisions Relating to Public... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED §§ 51-10.131—51-10.139...

  11. 10 CFR 1.39 - Office of Human Resources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Office of Human Resources. 1.39 Section 1.39 Energy... § 1.39 Office of Human Resources. The Office of Human Resources— (a) Plans and implements NRC policies... agency's human resources; (b) Provides labor relations and personnel policy guidance and...

  12. 21 CFR 139.160 - Vegetable noodle products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Vegetable noodle products. 139.160 Section 139.160... Noodle Products § 139.160 Vegetable noodle products. (a) Vegetable noodle products are the class of food... quantity that the solids thereof are not less than 3 percent by weight of the finished vegetable...

  13. 21 CFR 139.135 - Enriched vegetable macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched vegetable macaroni products. 139.135... Macaroni and Noodle Products § 139.135 Enriched vegetable macaroni products. (a) Each of the macaroni... requirements prescribed for enriched macaroni products by § 139.115 and contains a vegetable ingredient...

  14. 21 CFR 139.135 - Enriched vegetable macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched vegetable macaroni products. 139.135... Macaroni and Noodle Products § 139.135 Enriched vegetable macaroni products. (a) Each of the macaroni... requirements prescribed for enriched macaroni products by § 139.115 and contains a vegetable ingredient...

  15. 21 CFR 139.160 - Vegetable noodle products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Vegetable noodle products. 139.160 Section 139.160... Noodle Products § 139.160 Vegetable noodle products. (a) Vegetable noodle products are the class of food... quantity that the solids thereof are not less than 3 percent by weight of the finished vegetable...

  16. 21 CFR 139.135 - Enriched vegetable macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Enriched vegetable macaroni products. 139.135... Macaroni and Noodle Products § 139.135 Enriched vegetable macaroni products. (a) Each of the macaroni... requirements prescribed for enriched macaroni products by § 139.115 and contains a vegetable ingredient...

  17. 21 CFR 139.160 - Vegetable noodle products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Vegetable noodle products. 139.160 Section 139.160... Noodle Products § 139.160 Vegetable noodle products. (a) Vegetable noodle products are the class of food... quantity that the solids thereof are not less than 3 percent by weight of the finished vegetable...

  18. 21 CFR 139.160 - Vegetable noodle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Vegetable noodle products. 139.160 Section 139.160... Noodle Products § 139.160 Vegetable noodle products. (a) Vegetable noodle products are the class of food... quantity that the solids thereof are not less than 3 percent by weight of the finished vegetable...

  19. 21 CFR 139.135 - Enriched vegetable macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Enriched vegetable macaroni products. 139.135... Macaroni and Noodle Products § 139.135 Enriched vegetable macaroni products. (a) Each of the macaroni... requirements prescribed for enriched macaroni products by § 139.115 and contains a vegetable ingredient...

  20. 21 CFR 139.160 - Vegetable noodle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Vegetable noodle products. 139.160 Section 139.160... Noodle Products § 139.160 Vegetable noodle products. (a) Vegetable noodle products are the class of food... quantity that the solids thereof are not less than 3 percent by weight of the finished vegetable...

  1. 21 CFR 139.135 - Enriched vegetable macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Enriched vegetable macaroni products. 139.135... Macaroni and Noodle Products § 139.135 Enriched vegetable macaroni products. (a) Each of the macaroni... requirements prescribed for enriched macaroni products by § 139.115 and contains a vegetable ingredient...

  2. 22 CFR 139.8 - Target economic sectors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Target economic sectors. 139.8 Section 139.8 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH PEACE PROCESS CULTURAL AND TRAINING PROGRAM § 139.8 Target economic sectors. Job/Training under the IPPCTP will be authorized for preferred...

  3. 22 CFR 139.8 - Target economic sectors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Target economic sectors. 139.8 Section 139.8 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH PEACE PROCESS CULTURAL AND TRAINING PROGRAM § 139.8 Target economic sectors. Job/Training under the IPPCTP will be authorized for preferred...

  4. 22 CFR 139.8 - Target economic sectors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Target economic sectors. 139.8 Section 139.8 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH PEACE PROCESS CULTURAL AND TRAINING PROGRAM § 139.8 Target economic sectors. Job/Training under the IPPCTP will be authorized for preferred...

  5. 22 CFR 139.8 - Target economic sectors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Target economic sectors. 139.8 Section 139.8 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH PEACE PROCESS CULTURAL AND TRAINING PROGRAM § 139.8 Target economic sectors. Job/Training under the IPPCTP will be authorized for preferred...

  6. 22 CFR 139.8 - Target economic sectors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Target economic sectors. 139.8 Section 139.8 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH PEACE PROCESS CULTURAL AND TRAINING PROGRAM § 139.8 Target economic sectors. Job/Training under the IPPCTP will be authorized for preferred...

  7. 40 CFR 65.121-65.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 16 2014-07-01 2014-07-01 false 65.121-65.139 Section 65.121-65.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks §§ 65.121-65.139...

  8. 40 CFR 65.121-65.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false 65.121-65.139 Section 65.121-65.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks §§ 65.121-65.139...

  9. 40 CFR 65.121-65.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 16 2012-07-01 2012-07-01 false 65.121-65.139 Section 65.121-65.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks §§ 65.121-65.139...

  10. 40 CFR 65.121-65.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 16 2013-07-01 2013-07-01 false 65.121-65.139 Section 65.121-65.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks §§ 65.121-65.139...

  11. 40 CFR 65.121-65.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false 65.121-65.139 Section 65.121-65.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks §§ 65.121-65.139...

  12. 21 CFR 139.121 - Nonfat milk macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Nonfat milk macaroni products. 139.121 Section 139... and Noodle Products § 139.121 Nonfat milk macaroni products. (a) Each of the macaroni products made with nonfat milk for which a definition and standard of identity is prescribed by this section...

  13. 21 CFR 139.121 - Nonfat milk macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Nonfat milk macaroni products. 139.121 Section 139... and Noodle Products § 139.121 Nonfat milk macaroni products. (a) Each of the macaroni products made with nonfat milk for which a definition and standard of identity is prescribed by this section...

  14. 21 CFR 139.120 - Milk macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Milk macaroni products. 139.120 Section 139.120... Noodle Products § 139.120 Milk macaroni products. (a) Milk macaroni products are the class of food, each...), except that: (1) Milk is used as the sole moistening ingredient in preparing the dough; or in lieu...

  15. 21 CFR 139.121 - Nonfat milk macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Nonfat milk macaroni products. 139.121 Section 139... and Noodle Products § 139.121 Nonfat milk macaroni products. (a) Each of the macaroni products made with nonfat milk for which a definition and standard of identity is prescribed by this section...

  16. 21 CFR 139.120 - Milk macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Milk macaroni products. 139.120 Section 139.120... Noodle Products § 139.120 Milk macaroni products. (a) Milk macaroni products are the class of food, each...), except that: (1) Milk is used as the sole moistening ingredient in preparing the dough; or in lieu...

  17. 21 CFR 139.121 - Nonfat milk macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Nonfat milk macaroni products. 139.121 Section 139... and Noodle Products § 139.121 Nonfat milk macaroni products. (a) Each of the macaroni products made with nonfat milk for which a definition and standard of identity is prescribed by this section...

  18. 21 CFR 139.120 - Milk macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Milk macaroni products. 139.120 Section 139.120... Noodle Products § 139.120 Milk macaroni products. (a) Milk macaroni products are the class of food, each...), except that: (1) Milk is used as the sole moistening ingredient in preparing the dough; or in lieu...

  19. 21 CFR 139.121 - Nonfat milk macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Nonfat milk macaroni products. 139.121 Section 139... and Noodle Products § 139.121 Nonfat milk macaroni products. (a) Each of the macaroni products made with nonfat milk for which a definition and standard of identity is prescribed by this section...

  20. 21 CFR 139.120 - Milk macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk macaroni products. 139.120 Section 139.120... Noodle Products § 139.120 Milk macaroni products. (a) Milk macaroni products are the class of food, each...), except that: (1) Milk is used as the sole moistening ingredient in preparing the dough; or in lieu...

  1. 21 CFR 139.120 - Milk macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Milk macaroni products. 139.120 Section 139.120... Noodle Products § 139.120 Milk macaroni products. (a) Milk macaroni products are the class of food, each...), except that: (1) Milk is used as the sole moistening ingredient in preparing the dough; or in lieu...

  2. 24 CFR 9.132-9.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false 9.132-9.139 Section 9.132-9.139 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT §§ 9.132-9.139...

  3. 24 CFR 9.132-9.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false 9.132-9.139 Section 9.132-9.139 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT §§ 9.132-9.139...

  4. 22 CFR 530.131-530.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true 530.131-530.139 Section 530.131-530.139 Foreign Relations BROADCASTING BOARD OF GOVERNORS ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE BROADCASTING BOARD OF GOVERNORS §§ 530.131-530.139...

  5. 22 CFR 530.131-530.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 2 2012-04-01 2009-04-01 true 530.131-530.139 Section 530.131-530.139 Foreign Relations BROADCASTING BOARD OF GOVERNORS ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE BROADCASTING BOARD OF GOVERNORS §§ 530.131-530.139...

  6. 22 CFR 530.131-530.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true 530.131-530.139 Section 530.131-530.139 Foreign Relations BROADCASTING BOARD OF GOVERNORS ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE BROADCASTING BOARD OF GOVERNORS §§ 530.131-530.139...

  7. 22 CFR 530.131-530.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true 530.131-530.139 Section 530.131-530.139 Foreign Relations BROADCASTING BOARD OF GOVERNORS ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE BROADCASTING BOARD OF GOVERNORS §§ 530.131-530.139...

  8. 22 CFR 530.131-530.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false 530.131-530.139 Section 530.131-530.139 Foreign Relations BROADCASTING BOARD OF GOVERNORS ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE BROADCASTING BOARD OF GOVERNORS §§ 530.131-530.139...

  9. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole...

  10. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole...

  11. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole...

  12. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole...

  13. 49 CFR 213.139 - Spring rail frogs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Spring rail frogs. 213.139 Section 213.139..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.139 Spring rail frogs. (a) The... wing rail shall be solidly tamped and fully and tightly bolted. (c) Each frog with a bolt hole...

  14. 14 CFR 139.203 - Contents of Airport Certification Manual.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... procedures for maintaining, the marking, signs, and lighting systems, as required under § 139.311 X X X X 15... maintaining, the traffic and wind direction indicators, as required under § 139.323 X X X X 20. An emergency..., marking, or lighting, as required under § 139.331 X X X X 24. Procedures for protection of NAVAIDS,...

  15. 14 CFR 139.203 - Contents of Airport Certification Manual.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... procedures for maintaining, the marking, signs, and lighting systems, as required under § 139.311 X X X X 15... maintaining, the traffic and wind direction indicators, as required under § 139.323 X X X X 20. An emergency..., marking, or lighting, as required under § 139.331 X X X X 24. Procedures for protection of NAVAIDS,...

  16. 5 CFR 1850.131-1850.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false 1850.131-1850.139 Section 1850.131-1850.139 Administrative Personnel OFFICE OF SPECIAL COUNSEL ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE OFFICE OF SPECIAL COUNSEL §§ 1850.131-1850.139...

  17. 11 CFR 6.131-6.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false 6.131-6.139 Section 6.131-6.139 Federal Elections FEDERAL ELECTION COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE FEDERAL ELECTION COMMISSION §§ 6.131-6.139...

  18. 25 CFR 700.139 - Referral for action.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 2 2011-04-01 2011-04-01 false Referral for action. 700.139 Section 700.139 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Relocation Requirements § 700.139 Referral for action. Upon the expiration of all notice periods and upon...

  19. 25 CFR 700.139 - Referral for action.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 2 2013-04-01 2013-04-01 false Referral for action. 700.139 Section 700.139 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Relocation Requirements § 700.139 Referral for action. Upon the expiration of all notice periods and upon...

  20. 25 CFR 700.139 - Referral for action.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 2 2012-04-01 2012-04-01 false Referral for action. 700.139 Section 700.139 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Relocation Requirements § 700.139 Referral for action. Upon the expiration of all notice periods and upon...

  1. 25 CFR 700.139 - Referral for action.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Referral for action. 700.139 Section 700.139 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Relocation Requirements § 700.139 Referral for action. Upon the expiration of all notice periods and upon...

  2. 32 CFR 719.139-719.141 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false 719.139-719.141 Section 719.139-719.141 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PERSONNEL REGULATIONS SUPPLEMENTING THE MANUAL FOR COURTS-MARTIAL Miscellaneous Matters §§ 719.139-719.141...

  3. 14 CFR 125.139 - Oil system drains.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Oil system drains. 125.139 Section 125.139....139 Oil system drains. Accessible drains incorporating either a manual or automatic means for positive locking in the closed position must be provided to allow safe drainage of the entire oil system....

  4. 40 CFR 12.131-12.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false 12.131-12.139 Section 12.131-12.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE ENVIRONMENTAL PROTECTION AGENCY §§ 12.131-12.139...

  5. 45 CFR 1706.131-1706.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false 1706.131-1706.139 Section 1706.131-1706.139 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND... CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE §§ 1706.131-1706.139...

  6. 7 CFR 762.131-762.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false 762.131-762.139 Section 762.131-762.139 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS GUARANTEED FARM LOANS §§ 762.131-762.139...

  7. 40 CFR 12.131-12.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false 12.131-12.139 Section 12.131-12.139 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE ENVIRONMENTAL PROTECTION AGENCY §§ 12.131-12.139...

  8. 36 CFR 1208.131-1208.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true 1208.131-1208.139 Section 1208.131-1208.139 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL... THE NATIONAL ARCHIVES AND RECORDS ADMINISTRATION §§ 1208.131-1208.139...

  9. 36 CFR 1208.131-1208.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false 1208.131-1208.139 Section 1208.131-1208.139 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION... CONDUCTED BY THE NATIONAL ARCHIVES AND RECORDS ADMINISTRATION §§ 1208.131-1208.139...

  10. 36 CFR 1208.131-1208.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false 1208.131-1208.139 Section 1208.131-1208.139 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION... CONDUCTED BY THE NATIONAL ARCHIVES AND RECORDS ADMINISTRATION §§ 1208.131-1208.139...

  11. 36 CFR 1154.131-1154.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false 1154.131-1154.139 Section 1154.131-1154.139 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION BARRIERS... CONDUCTED BY THE ARCHITECTURAL AND TRANSPORTATION BARRIERS COMPLIANCE BOARD §§ 1154.131-1154.139...

  12. 25 CFR 139.2 - Repayment of construction costs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Repayment of construction costs. 139.2 Section 139.2 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES REIMBURSEMENT OF CONSTRUCTION COSTS, WAPATO-SATUS UNIT, WAPATO INDIAN IRRIGATION PROJECT, WASHINGTON § 139.2 Repayment...

  13. 32 CFR 644.139 - Leases for civil works purposes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Leases for civil works purposes. 644.139 Section 644.139 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Acquisition Acquisition by Leasing § 644.139 Leases for civil works...

  14. 32 CFR 644.139 - Leases for civil works purposes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Leases for civil works purposes. 644.139 Section 644.139 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Acquisition Acquisition by Leasing § 644.139 Leases for civil works...

  15. 14 CFR 125.139 - Oil system drains.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Oil system drains. 125.139 Section 125.139....139 Oil system drains. Accessible drains incorporating either a manual or automatic means for positive locking in the closed position must be provided to allow safe drainage of the entire oil system....

  16. 14 CFR 125.139 - Oil system drains.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Oil system drains. 125.139 Section 125.139....139 Oil system drains. Accessible drains incorporating either a manual or automatic means for positive locking in the closed position must be provided to allow safe drainage of the entire oil system....

  17. 14 CFR 125.139 - Oil system drains.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Oil system drains. 125.139 Section 125.139....139 Oil system drains. Accessible drains incorporating either a manual or automatic means for positive locking in the closed position must be provided to allow safe drainage of the entire oil system....

  18. 14 CFR 125.139 - Oil system drains.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Oil system drains. 125.139 Section 125.139....139 Oil system drains. Accessible drains incorporating either a manual or automatic means for positive locking in the closed position must be provided to allow safe drainage of the entire oil system....

  19. Optical glass surfaces polishing by cerium oxide particles

    NASA Astrophysics Data System (ADS)

    Bouzid, D.; Belkhie, N.; Aliouane, T.

    2012-02-01

    The use of powders in metallic oxides as means of grinding and polishing of the optical glass components have seen recently a large application in optical industry. In fact, cerium oxide abrasive is more used in the optical glass polishing. It is used as grains abrasive in suspension or fixed abrasive (pellets); these pellets are manufactured from a mixture made of cerium oxide abrasive and a organic binder. The cerium oxide used in the experiments is made by (Logitech USA) of 99 % purity, the average grain size of the particle is 300 nm, the density being 6,74 g /cm3 and the specific surface is 3,3042 m2/g. In this study, we are interested in the surfaces quality of the optical glass borosilicate crown (BK7) polished by particles in cerium oxide bounded by epoxy. The surfaces of the optical glass treated are characterized by the roughness, the flatness by using the microscope Zygo and the SEM.

  20. Cerium migration during PEM fuel cell assembly and operation

    DOE PAGES

    Baker, Andrew M.; Torraco, Dennis; Judge, Elizabeth J.; Spernjak, Dusan; Mukundan, Rangachary; Borup, Rod L.; Advani, Suresh G.; Prasad, Ajay K.

    2015-09-14

    Cerium migration between PEM fuel cell components is influenced by potential-driven mobility, ionic diffusion, and gradients in water content. These factors were investigated in ex situ experiments and in operating fuel cells. Potential-induced migration was measured ex situ in hydrated window cells. Cerium-containing MEAs were also fabricated and tested under ASTs. MEA disassembly and subsequent XRF analysis were used to observe rapid cerium migration during cell assembly and operation. During MEA hot pressing, humidification, and low RH operation at OCV, ionic diffusion causes uniform migration from the membrane into the catalyst layers. During high RH operation at OCV, in-plane ceriummore » gradients arise due to variations in water content. These gradients may diminish the scavenging efficacy of cerium by reducing its proximity to generated radicals.« less

  1. Effects of the Rare Earth Cerium on Escherichia coli

    PubMed Central

    Sobek, Joseph M.; Talburt, Dwight E.

    1968-01-01

    The rare earth cerium was found to bind rapidly to Escherichia coli. Cerium inhibited oxygen uptake in the presence of glucose as well as the endogenous respiration of glucose-grown cells. For a cell concentration of 4 mg per ml, maximal inhibition was obtained at 120 μg per ml. Greater concentrations did not increase the inhibitory effect. Cerium inhibited 14CO2 evolution and 14C uptake from uniformly labeled glucose. Marked changes in the distribution of 14C incorporated into different chemical fractions of the cell were noted. The most striking changes occurred in the alcohol- and alcohol ether-soluble fractions, in which the 14C activity was increased 5- to 20-fold in the presence of cerium. PMID:4866102

  2. Heteroaggregation of cerium oxide nanoparticles and nanoparticles of pyrolyzed biomass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heteroaggregation with indigenous particles is an important process controlling the mobility of engineered nanomaterials in the environment. We studied heteroaggregation of cerium oxide nanoparticles (n-CeO2), which are widely used commercially, with nanoparticles of pyrogenic carbonaceous material ...

  3. Analysis of S.139, the Climate Stewardship Act of 2003

    EIA Publications

    2003-01-01

    On January 9, 2003, Senators John McCain and Joseph I. Lieberman introduced Senate Bill 139 (S.139), the Climate Stewardship Act of 2003, in the U.S. Senate. S.139 would require the Administrator of the U.S. Environmental Protection Agency (EPA) to promulgate regulations to limit greenhouse gas emissions. On January 28, 2003, Senator James M. Inhofe requested that the Energy Information Administration (EIA) perform a comprehensive analysis of S.139. On April 2, 2003, Senators McCain and Lieberman, cosponsors of S.139, made a further request for analyses of their bill. This Service Report responds to both requests.

  4. Method of applying a cerium diffusion coating to a metallic alloy

    DOEpatents

    Jablonski, Paul D.; Alman, David E.

    2009-06-30

    A method of applying a cerium diffusion coating to a preferred nickel base alloy substrate has been discovered. A cerium oxide paste containing a halide activator is applied to the polished substrate and then dried. The workpiece is heated in a non-oxidizing atmosphere to diffuse cerium into the substrate. After cooling, any remaining cerium oxide is removed. The resulting cerium diffusion coating on the nickel base substrate demonstrates improved resistance to oxidation. Cerium coated alloys are particularly useful as components in a solid oxide fuel cell (SOFC).

  5. Control of cerium oxidation state through metal complex secondary structures

    DOE PAGES

    Levin, Jessica R.; Dorfner, Walter L.; Carroll, Patrick J.; Schelter, Eric J.

    2015-08-11

    A series of alkali metal cerium diphenylhydrazido complexes, Mx(py)y[Ce(PhNNPh)4], M = Li, Na, and K, x = 4 (Li and Na) or 5 (K), and y = 4 (Li), 8 (Na), or 7 (K), were synthesized to probe how a secondary coordination sphere would modulate electronic structures at a cerium cation. The resulting electronic structures of the heterobimetallic cerium diphenylhydrazido complexes were found to be strongly dependent on the identity of the alkali metal cations. When M = Li+ or Na+, the cerium(III) starting material was oxidized with concomitant reduction of 1,2-diphenylhydrazine to aniline. Reduction of 1,2-diphenylhydrazine was not observedmore » when M = K+, and the complex remained in the cerium(III) oxidation state. Oxidation of the cerium(III) diphenylhydrazido complex to the Ce(IV) diphenylhydrazido one was achieved through a simple cation exchange reaction of the alkali metals. As a result, UV-Vis spectroscopy, FTIR spectroscopy, electrochemistry, magnetic susceptibility, and DFT studies were used to probe the oxidation state and the electronic changes that occurred at the metal centre.« less

  6. Control of cerium oxidation state through metal complex secondary structures

    SciTech Connect

    Levin, Jessica R.; Dorfner, Walter L.; Carroll, Patrick J.; Schelter, Eric J.

    2015-08-11

    A series of alkali metal cerium diphenylhydrazido complexes, Mx(py)y[Ce(PhNNPh)4], M = Li, Na, and K, x = 4 (Li and Na) or 5 (K), and y = 4 (Li), 8 (Na), or 7 (K), were synthesized to probe how a secondary coordination sphere would modulate electronic structures at a cerium cation. The resulting electronic structures of the heterobimetallic cerium diphenylhydrazido complexes were found to be strongly dependent on the identity of the alkali metal cations. When M = Li+ or Na+, the cerium(III) starting material was oxidized with concomitant reduction of 1,2-diphenylhydrazine to aniline. Reduction of 1,2-diphenylhydrazine was not observed when M = K+, and the complex remained in the cerium(III) oxidation state. Oxidation of the cerium(III) diphenylhydrazido complex to the Ce(IV) diphenylhydrazido one was achieved through a simple cation exchange reaction of the alkali metals. As a result, UV-Vis spectroscopy, FTIR spectroscopy, electrochemistry, magnetic susceptibility, and DFT studies were used to probe the oxidation state and the electronic changes that occurred at the metal centre.

  7. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR CERIUM OXIDE (STABLE) AND COMPOUNDS

    EPA Science Inventory

    Cerium is a member of the lanthanoid series of rare earth metals. It is also the most abundant and most reactive of the rare earth metals. Cerium oxidizes at room temperature and forms a variety of salt compounds including oxides, hydroxides, sulfates and chlorides. Cerium is ...

  8. Potential for recovery of cerium contained in automotive catalytic converters

    USGS Publications Warehouse

    Bleiwas, Donald I.

    2013-01-01

    Catalytic converters (CATCONs) are required by Federal law to be installed in nearly all gasoline- and diesel-fueled onroad vehicles used in the United States. About 85 percent of the light-duty vehicles and trucks manufactured worldwide are equipped with CATCONs. Portions of the CATCONs (called monoliths) are recycled for their platinum-group metal (PGM) content and for the value of the stainless steel they contain. The cerium contained in the monoliths, however, is disposed of along with the slag produced from the recycling process. Although there is some smelter capacity in the United States to treat the monoliths in order to recover the PGMs, a great percentage of monoliths is exported to Europe and South Africa for recycling, and a lesser amount is exported to Japan. There is presently no commercial-scale capacity in place domestically to recover cerium from the monoliths. Recycling of cerium or cerium compounds from the monoliths could help ensure against possible global supply shortages by increasing the amount that is available in the supply chain as well as the number and geographic distribution of the suppliers. It could also reduce the amount of material that goes into landfills. Also, the additional supply could lower the price of the commodity. This report analyzes how much cerium oxide is contained in CATCONs and how much could be recovered from used CATCONs.

  9. Mechanical and Thermophysical Properties of Cerium Monopnictides

    NASA Astrophysics Data System (ADS)

    Bhalla, Vyoma; Singh, Devraj; Jain, S. K.

    2016-03-01

    The ultrasonic attenuation due to phonon-phonon interaction, thermoelastic relaxation and dislocation damping mechanisms has been investigated in cerium monopnictides CeX (X: N, P, As, Sb and Bi) for longitudinal and shear waves along {< }100{rangle }, {< }110{rangle } and {< }111{rangle } directions. The second- and third-order elastic constants of CeX have also been computed in the temperature range 0 K to 500 K using Coulomb and Born-Mayer potential upto second nearest neighbours. The computed values of these elastic constants have been applied to find out Young's moduli, bulk moduli, Breazeale's non-linearity parameters, Zener anisotropy, ultrasonic velocity, ultrasonic Grüneisen parameter, thermal relaxation time, acoustic coupling constants and ultrasonic attenuation. The fracture/toughness ratio is less than 1.75, which shows that the chosen materials are brittle in nature as found for other monopnictides. The drag coefficient acting on the motion of screw and edge dislocations due to shear and compressional phonon viscosities of the lattice have also been evaluated for both the longitudinal and shear waves. The thermoelastic loss and dislocation damping loss are negligible in comparison to loss due to Akhieser damping (phonon-phonon interaction). The obtained results for CeX are in qualitative agreement with other semi-metallic monopnictides.

  10. Characterization of cerium fluoride nanocomposite scintillators

    SciTech Connect

    Stange, Sy; Esch, Ernst I; Brown, Leif O; Couture, Aaron J; Mckigney, Edward A; Muenchausen, Ross E; Del Sesto, Rico E; Gilbertson, Robert D; Mccleskey, T Mark; Reifarth, Rene

    2009-01-01

    Measurement of the neutron capture cross-sections of a number of short-lived isotopes would advance both pure and applied scientific research. These cross-sections are needed for calculation of criticality and waste production estimates for the Advanced Fuel Cycle Initiative, for analysis of data from nuclear weapons tests, and to improve understanding of nucleosynthesis. However, measurement of these cross-sections would require a detector with a faster signal decay time than those used in existing neutron capture experiments. Crystals of faster detector materials are not available in sufficient sizes and quantities to supply these large-scale experiments. Instead, we propose to use nanocomposite detectors, consisting of nanoscale particles of a scintillating material dispersed in a matrix material. We have successfully fabricated cerium fluoride (CeF{sub 3}) nanoparticles and dispersed them in a liquid matrix. We have characterized this scintillator and have measured its response to neutron capture. Results of the optical, structural, and radiation characterization will be presented.

  11. Environmental Geochemistry of Cerium: Applications and Toxicology of Cerium Oxide Nanoparticles

    PubMed Central

    Dahle, Jessica T.; Arai, Yuji

    2015-01-01

    Cerium is the most abundant of rare-earth metals found in the Earth’s crust. Several Ce-carbonate, -phosphate, -silicate, and -(hydr)oxide minerals have been historically mined and processed for pharmaceutical uses and industrial applications. Of all Ce minerals, cerium dioxide has received much attention in the global nanotechnology market due to their useful applications for catalysts, fuel cells, and fuel additives. A recent mass flow modeling study predicted that a major source of CeO2 nanoparticles from industrial processing plants (e.g., electronics and optics manufactures) is likely to reach the terrestrial environment such as landfills and soils. The environmental fate of CeO2 nanoparticles is highly dependent on its physcochemical properties in low temperature geochemical environment. Though there are needs in improving the analytical method in detecting/quantifying CeO2 nanoparticles in different environmental media, it is clear that aquatic and terrestrial organisms have been exposed to CeO2 NPs, potentially yielding in negative impact on human and ecosystem health. Interestingly, there has been contradicting reports about the toxicological effects of CeO2 nanoparticles, acting as either an antioxidant or reactive oxygen species production-inducing agent). This poses a challenge in future regulations for the CeO2 nanoparticle application and the risk assessment in the environment. PMID:25625406

  12. Thermodynamic Calculation among Cerium, Oxygen, and Sulfur in Liquid Iron

    PubMed Central

    Pan, Fei; Zhang, Jian; Chen, Hao-Long; Su, Yen-Hsun; Su, Yen-Hao; Hwang, Weng-Sing

    2016-01-01

    Thermodynamic calculation has been applied to predict the inclusion formation in molten SS400 steel. When the Cerium addition in liquid iron is 70 ppm and the initial Oxygen and Sulphur are both 110 ppm, the formation of oxides containing Cerium would experience the transformation from Ce2O3 to CeO2 and also the formation of sulfides containing Cerium would experience the transformation from CeS to Ce2S3 and then to Ce3S4. Below 2000 K the most thermodynamic stable matter is CeO2 and the less thermodynamic stable inclusion is CeS. Only when the amount of [O] is extremely low and the amount of [S] and [Ce] is relatively high, Ce2S3 has the possibility to form. PMID:27767092

  13. Dehydrogenation of isopropanol on a cerium-nickel catalyst

    NASA Astrophysics Data System (ADS)

    Platonov, E. A.; Naumkin, A. V.; Maslakov, K. I.; Yagodovskii, V. D.

    2012-12-01

    The effect of a cerium additive on the catalytic activity of a 2 wt % Ni/SiO2 catalyst is studied. It found that under both flow and static conditions the activity of (2 wt % Ni + 0.2 wt % Ce)/SiO2 catalyst is higher than that of the original sample; the increase in activity results from a sharp increase in the number of active sites. A change in the composition of the surface layer of the catalysts is analyzed by X-ray photoelectron spectroscopy. It was found that the fraction of nickel decreases and the fraction of carbon increases in cerium-containing catalyst. An explanation of the change in the elemental composition of the catalytic active sites of a nickel catalyst in the presence of cerium is proposed on the basis of XPS data and previous quantum chemical calculations.

  14. Synthesis and characterization of magnesium doped cerium oxide for the fuel cell application

    NASA Astrophysics Data System (ADS)

    Kumar, Amit; Kumari, Monika; Kumar, Mintu; Kumar, Sacheen; Kumar, Dinesh

    2016-05-01

    Cerium oxide has attained much attentions in global nanotechnology market due to valuable application for catalytic, fuel additive, and widely as electrolyte in solid oxide fuel cell. Doped cerium oxide has large oxygen vacancies that allow for greater reactivity and faster ion transport. These properties make cerium oxide suitable material for SOFCs application. Cerium oxide electrolyte requires lower operation temperature which shows improvement in processing and the fabrication technique. In our work, we synthesized magnesium doped cerium oxide by the co-precipitation method. With the magnesium doping catalytic reactivity of CeO2 was increased. Synthesized nanoparticle were characterized by the XRD and UV absorption techniques.

  15. In situ growth of epitaxial cerium tungstate (100) thin films.

    PubMed

    Skála, Tomáš; Tsud, Nataliya; Orti, Miguel Ángel Niño; Menteş, Tevfik Onur; Locatelli, Andrea; Prince, Kevin Charles; Matolín, Vladimír

    2011-04-21

    The deposition of ceria on a preoxidized W(110) crystal at 870 K has been studied in situ by photoelectron spectroscopy and low-energy electron diffraction. Formation of an epitaxial layer of crystalline cerium tungstate Ce(6)WO(12)(100), with the metals in the Ce(3+) and W(6+) chemical states, has been observed. The interface between the tungsten substrate and the tungstate film consists of WO suboxide. At thicknesses above 0.89 nm, cerium dioxide grows on the surface of Ce(6)WO(12), favoured by the limited diffusion of tungsten from the substrate. PMID:21399780

  16. Optical and electrical studies of cerium mixed oxides

    SciTech Connect

    Sherly, T. R.; Raveendran, R.

    2014-10-15

    The fast development in nanotechnology makes enthusiastic interest in developing nanomaterials having tailor made properties. Cerium mixed oxide materials have received great attention due to their UV absorption property, high reactivity, stability at high temperature, good electrical property etc and these materials find wide applications in solid oxide fuel cells, solar control films, cosmetics, display units, gas sensors etc. In this study cerium mixed oxide compounds were prepared by co-precipitation method. All the samples were doped with Zn (II) and Fe (II). Preliminary characterizations such as XRD, SEM / EDS, TEM were done. UV - Vis, Diffuse reflectance, PL, FT-IR, Raman and ac conductivity studies of the samples were performed.

  17. The effective thermal conductivity of an adsorbent - Praseodymium cerium oxide

    NASA Technical Reports Server (NTRS)

    Secary, J. J.; Tong, T. W.

    1992-01-01

    The results of an experimental study to determine the effective thermal conductivity of praseodymium cerium oxide are reported. Praseodymium cerium oxide is an adsorbent used in the development of adsorption compressors for spaceborne refrigeration systems. A guarded-hot-plate apparatus was built for this study. Measurements were carried out for mean temperatures ranging from 300 to 600 C under a vacuum of 10 exp -5 torr. For the temperature range studied, the effective thermal conductivity increased from 0.14 to 0.76 W/m per C with increasing temperature, while displaying a cubic temperature dependency.

  18. Cerium phosphate nanotubes: synthesis, characterization and biosensing

    NASA Astrophysics Data System (ADS)

    Meng, Ling; Yang, Lige; Zhou, Bo; Cai, Chenxin

    2009-01-01

    Cerium phosphate (CeP) nanotubes have been synthesized and confirmed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). The 1D nanomaterial has a monoclinic crystal structure with a mean width of 15-20 nm and a length up to several micrometers. The nanotubes have been employed as electrode substrates for immobilization and direct electrochemistry of heme proteins/enzymes with myoglobin (Mb) as a model. The electrochemical characteristics of the Mb-CeP/GC electrode were studied by voltammetry. After being immobilized on the nanotubes, Mb can keep its natural structure and undergo effective direct electron transfer reaction with a pair of well-defined redox peaks at -(367 ± 3) mV (pH 7.5). The apparent electron transfer rate constant is (9.1 ± 1.4) s-1. The electrode displays good features in the electrocatalytic reduction of H2O2, and thus can be used as a biosensor for detecting the substrate with a low detection limit (0.5 ± 0.05 µM), a wide linear range (0.01-2 mM), high sensitivity (14.4 ± 1.2 µA mM-1), as well as good stability and reproducibility. CeP nanotubes can become a simple and effective biosensing platform for the integration of heme proteins/enzymes and electrodes, which can provide analytical access to a large group of enzymes for a wide range of bioelectrochemical applications.

  19. 21 CFR 139.140 - Wheat and soy macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Wheat and soy macaroni products. 139.140 Section... Macaroni and Noodle Products § 139.140 Wheat and soy macaroni products. (a) Wheat and soy macaroni products... percent of the combined weight of the wheat and soy ingredients used (the soy flour used is made from...

  20. 21 CFR 139.140 - Wheat and soy macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Wheat and soy macaroni products. 139.140 Section... Macaroni and Noodle Products § 139.140 Wheat and soy macaroni products. (a) Wheat and soy macaroni products... percent of the combined weight of the wheat and soy ingredients used (the soy flour used is made from...

  1. 21 CFR 139.140 - Wheat and soy macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Wheat and soy macaroni products. 139.140 Section... Macaroni and Noodle Products § 139.140 Wheat and soy macaroni products. (a) Wheat and soy macaroni products... percent of the combined weight of the wheat and soy ingredients used (the soy flour used is made from...

  2. 21 CFR 139.140 - Wheat and soy macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Wheat and soy macaroni products. 139.140 Section... Macaroni and Noodle Products § 139.140 Wheat and soy macaroni products. (a) Wheat and soy macaroni products... percent of the combined weight of the wheat and soy ingredients used (the soy flour used is made from...

  3. 21 CFR 139.140 - Wheat and soy macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Wheat and soy macaroni products. 139.140 Section... Macaroni and Noodle Products § 139.140 Wheat and soy macaroni products. (a) Wheat and soy macaroni products... percent of the combined weight of the wheat and soy ingredients used (the soy flour used is made from...

  4. 36 CFR 223.139 - Period of debarment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Period of debarment. 223.139 Section 223.139 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST BOTANICAL...

  5. 32 CFR 1906.131-1906.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false 1906.131-1906.139 Section 1906.131-1906.139 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE CENTRAL INTELLIGENCE...

  6. 32 CFR 1906.131-1906.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false 1906.131-1906.139 Section 1906.131-1906.139 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE CENTRAL INTELLIGENCE...

  7. 32 CFR 1906.131-1906.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false 1906.131-1906.139 Section 1906.131-1906.139 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE CENTRAL INTELLIGENCE...

  8. 32 CFR 1906.131-1906.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false 1906.131-1906.139 Section 1906.131-1906.139 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE CENTRAL INTELLIGENCE...

  9. 14 CFR 139.311 - Marking, signs, and lighting.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Marking, signs, and lighting. 139.311... OF AIRPORTS Operations § 139.311 Marking, signs, and lighting. (a) Marking. Each certificate holder...) and (b)(1)(iii) of this section must be internally illuminated at each Class III airport. (c)...

  10. 14 CFR 139.311 - Marking, signs, and lighting.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Marking, signs, and lighting. 139.311... OF AIRPORTS Operations § 139.311 Marking, signs, and lighting. (a) Marking. Each certificate holder...) and (b)(1)(iii) of this section must be internally illuminated at each Class III airport. (c)...

  11. 14 CFR 139.311 - Marking, signs, and lighting.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Marking, signs, and lighting. 139.311... OF AIRPORTS Operations § 139.311 Marking, signs, and lighting. (a) Marking. Each certificate holder...) and (b)(1)(iii) of this section must be internally illuminated at each Class III airport. (c)...

  12. 14 CFR 139.323 - Traffic and wind direction indicators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Traffic and wind direction indicators. 139... CERTIFICATION OF AIRPORTS Operations § 139.323 Traffic and wind direction indicators. In a manner authorized by...) A wind cone that visually provides surface wind direction information to pilots. For each...

  13. 14 CFR 139.323 - Traffic and wind direction indicators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Traffic and wind direction indicators. 139... CERTIFICATION OF AIRPORTS Operations § 139.323 Traffic and wind direction indicators. In a manner authorized by...) A wind cone that visually provides surface wind direction information to pilots. For each...

  14. 14 CFR 139.323 - Traffic and wind direction indicators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Traffic and wind direction indicators. 139... CERTIFICATION OF AIRPORTS Operations § 139.323 Traffic and wind direction indicators. In a manner authorized by...) A wind cone that visually provides surface wind direction information to pilots. For each...

  15. 14 CFR 139.323 - Traffic and wind direction indicators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Traffic and wind direction indicators. 139... CERTIFICATION OF AIRPORTS Operations § 139.323 Traffic and wind direction indicators. In a manner authorized by...) A wind cone that visually provides surface wind direction information to pilots. For each...

  16. 14 CFR 139.323 - Traffic and wind direction indicators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Traffic and wind direction indicators. 139... CERTIFICATION OF AIRPORTS Operations § 139.323 Traffic and wind direction indicators. In a manner authorized by...) A wind cone that visually provides surface wind direction information to pilots. For each...

  17. 14 CFR 91.139 - Emergency air traffic rules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Emergency air traffic rules. 91.139 Section...) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Flight Rules General § 91.139 Emergency air traffic rules. (a) This section prescribes a process for utilizing Notices to...

  18. 7 CFR 1703.138-1703.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false 1703.138-1703.139 Section 1703.138-1703.139 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Combination Loan and Grant Program §§...

  19. 7 CFR 1703.138-1703.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 11 2013-01-01 2013-01-01 false 1703.138-1703.139 Section 1703.138-1703.139 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Combination Loan and Grant Program §§...

  20. 7 CFR 1703.138-1703.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 11 2014-01-01 2014-01-01 false 1703.138-1703.139 Section 1703.138-1703.139 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Combination Loan and Grant Program §§...

  1. 7 CFR 1703.138-1703.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 11 2012-01-01 2012-01-01 false 1703.138-1703.139 Section 1703.138-1703.139 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Combination Loan and Grant Program §§...

  2. 7 CFR 1703.138-1703.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 11 2011-01-01 2011-01-01 false 1703.138-1703.139 Section 1703.138-1703.139 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Combination Loan and Grant Program §§...

  3. 27 CFR 9.139 - Santa Lucia Highlands.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....139 Section 9.139 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... (photorevised 1984) (5) Soledad, Calif., 1955 (photorevised 1984) (6) Sycamore Flat, Calif., 1956 (photorevised... straight diagonal line to the northwest corner of section 24, T. 18S., R. 5E on the Sycamore...

  4. 32 CFR 935.139 - Motor vehicle operator qualifications.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Motor vehicle operator qualifications. 935.139... AND INSULAR REGULATIONS WAKE ISLAND CODE Motor Vehicle Code § 935.139 Motor vehicle operator qualifications. (a) No person may operate a privately owned motor vehicle on Wake Island unless he has an...

  5. 32 CFR 935.139 - Motor vehicle operator qualifications.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Motor vehicle operator qualifications. 935.139... AND INSULAR REGULATIONS WAKE ISLAND CODE Motor Vehicle Code § 935.139 Motor vehicle operator qualifications. (a) No person may operate a privately owned motor vehicle on Wake Island unless he has an...

  6. 32 CFR 935.139 - Motor vehicle operator qualifications.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Motor vehicle operator qualifications. 935.139... AND INSULAR REGULATIONS WAKE ISLAND CODE Motor Vehicle Code § 935.139 Motor vehicle operator qualifications. (a) No person may operate a privately owned motor vehicle on Wake Island unless he has an...

  7. 36 CFR 406.131-406.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false 406.131-406.139 Section 406.131-406.139 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY AMERICAN BATTLE...

  8. 36 CFR 406.131-406.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true 406.131-406.139 Section 406.131-406.139 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY AMERICAN BATTLE...

  9. 36 CFR 406.131-406.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false 406.131-406.139 Section 406.131-406.139 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY AMERICAN BATTLE...

  10. 36 CFR 406.131-406.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false 406.131-406.139 Section 406.131-406.139 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY AMERICAN BATTLE...

  11. 36 CFR 406.131-406.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false 406.131-406.139 Section 406.131-406.139 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY AMERICAN BATTLE...

  12. 21 CFR 139.165 - Enriched vegetable noodle products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Enriched vegetable noodle products. 139.165... Macaroni and Noodle Products § 139.165 Enriched vegetable noodle products. (a) Each of the noodle products... a vegetable ingredient in compliance with the requirements prescribed for vegetable noodle...

  13. 21 CFR 139.165 - Enriched vegetable noodle products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Enriched vegetable noodle products. 139.165... Macaroni and Noodle Products § 139.165 Enriched vegetable noodle products. (a) Each of the noodle products... a vegetable ingredient in compliance with the requirements prescribed for vegetable noodle...

  14. 21 CFR 139.165 - Enriched vegetable noodle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched vegetable noodle products. 139.165... Macaroni and Noodle Products § 139.165 Enriched vegetable noodle products. (a) Each of the noodle products... a vegetable ingredient in compliance with the requirements prescribed for vegetable noodle...

  15. 21 CFR 139.165 - Enriched vegetable noodle products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Enriched vegetable noodle products. 139.165... Macaroni and Noodle Products § 139.165 Enriched vegetable noodle products. (a) Each of the noodle products... a vegetable ingredient in compliance with the requirements prescribed for vegetable noodle...

  16. 21 CFR 139.165 - Enriched vegetable noodle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched vegetable noodle products. 139.165... Macaroni and Noodle Products § 139.165 Enriched vegetable noodle products. (a) Each of the noodle products... a vegetable ingredient in compliance with the requirements prescribed for vegetable noodle...

  17. 19 CFR 201.131-201.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 3 2011-04-01 2011-04-01 false 201.131-201.139 Section 201.131-201.139 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION GENERAL RULES OF GENERAL APPLICATION Enforcement of Nondiscrimination on the Basis of Handicap in Programs or Activities Conducted by the U.S. International...

  18. 19 CFR 201.131-201.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false 201.131-201.139 Section 201.131-201.139 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION GENERAL RULES OF GENERAL APPLICATION Enforcement of Nondiscrimination on the Basis of Handicap in Programs or Activities Conducted by the U.S. International...

  19. 14 CFR 139.203 - Contents of Airport Certification Manual.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Contents of Airport Certification Manual. 139.203 Section 139.203 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... succession of airport operational responsibility X X X X 2. Each current exemption issued to the airport...

  20. 14 CFR 139.203 - Contents of Airport Certification Manual.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Contents of Airport Certification Manual. 139.203 Section 139.203 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... succession of airport operational responsibility X X X X 2. Each current exemption issued to the airport...

  1. 14 CFR 139.203 - Contents of Airport Certification Manual.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Contents of Airport Certification Manual. 139.203 Section 139.203 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... succession of airport operational responsibility X X X X 2. Each current exemption issued to the airport...

  2. 36 CFR 223.139 - Period of debarment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Period of debarment. 223.139 Section 223.139 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST BOTANICAL...

  3. 36 CFR 223.139 - Period of debarment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Period of debarment. 223.139 Section 223.139 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST BOTANICAL...

  4. 36 CFR 223.139 - Period of debarment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Period of debarment. 223.139 Section 223.139 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER, SPECIAL FOREST PRODUCTS, AND FOREST BOTANICAL...

  5. 49 CFR 229.139 - Sanitation, servicing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Sanitation, servicing requirements. 229.139... Cab Equipment § 229.139 Sanitation, servicing requirements. (a) The sanitation compartment of each... present that prevents waste from evacuating the bowl. (c) The sanitation compartment of each...

  6. 49 CFR 229.139 - Sanitation, servicing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Sanitation, servicing requirements. 229.139... Cab Equipment § 229.139 Sanitation, servicing requirements. (a) The sanitation compartment of each... present that prevents waste from evacuating the bowl. (c) The sanitation compartment of each...

  7. 21 CFR 139.122 - Enriched nonfat milk macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched nonfat milk macaroni products. 139.122... Macaroni and Noodle Products § 139.122 Enriched nonfat milk macaroni products. (a) Each of the enriched macaroni products made with nonfat milk for which a definition and standard of identity is prescribed...

  8. 21 CFR 139.122 - Enriched nonfat milk macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Enriched nonfat milk macaroni products. 139.122... Macaroni and Noodle Products § 139.122 Enriched nonfat milk macaroni products. (a) Each of the enriched macaroni products made with nonfat milk for which a definition and standard of identity is prescribed...

  9. 22 CFR 1600.131-1600.139 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true 1600.131-1600.139 Section 1600.131-1600.139 Foreign Relations JAPAN-UNITED STATES FRIENDSHIP COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE JAPAN-UNITED STATES FRIENDSHIP...

  10. 14 CFR 91.139 - Emergency air traffic rules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Emergency air traffic rules. 91.139 Section...) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Flight Rules General § 91.139 Emergency air traffic rules. (a) This section prescribes a process for utilizing Notices to...

  11. 14 CFR 139.311 - Marking, signs, and lighting.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Marking, signs, and lighting. 139.311... OF AIRPORTS Operations § 139.311 Marking, signs, and lighting. (a) Marking. Each certificate holder...) and (b)(1)(iii) of this section must be internally illuminated at each Class III airport. (c)...

  12. 14 CFR 139.311 - Marking, signs, and lighting.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Marking, signs, and lighting. 139.311... OF AIRPORTS Operations § 139.311 Marking, signs, and lighting. (a) Marking. Each certificate holder...) and (b)(1)(iii) of this section must be internally illuminated at each Class III airport. (c)...

  13. 5 CFR 185.139 - Appeal to authority head.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Appeal to authority head. 185.139 Section... FRAUD CIVIL REMEDIES § 185.139 Appeal to authority head. (a) Any defendant who has filed a timely answer... such decision to the authority head by filing a notice of appeal with the authority head in...

  14. 5 CFR 185.139 - Appeal to authority head.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Appeal to authority head. 185.139 Section... FRAUD CIVIL REMEDIES § 185.139 Appeal to authority head. (a) Any defendant who has filed a timely answer... such decision to the authority head by filing a notice of appeal with the authority head in...

  15. 5 CFR 185.139 - Appeal to authority head.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Appeal to authority head. 185.139 Section... FRAUD CIVIL REMEDIES § 185.139 Appeal to authority head. (a) Any defendant who has filed a timely answer... such decision to the authority head by filing a notice of appeal with the authority head in...

  16. 5 CFR 185.139 - Appeal to authority head.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Appeal to authority head. 185.139 Section... FRAUD CIVIL REMEDIES § 185.139 Appeal to authority head. (a) Any defendant who has filed a timely answer... such decision to the authority head by filing a notice of appeal with the authority head in...

  17. 5 CFR 185.139 - Appeal to authority head.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Appeal to authority head. 185.139 Section... FRAUD CIVIL REMEDIES § 185.139 Appeal to authority head. (a) Any defendant who has filed a timely answer... such decision to the authority head by filing a notice of appeal with the authority head in...

  18. 22 CFR 1600.131-1600.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true 1600.131-1600.139 Section 1600.131-1600.139 Foreign Relations JAPAN-UNITED STATES FRIENDSHIP COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE JAPAN-UNITED STATES FRIENDSHIP...

  19. 14 CFR 139.205 - Amendment of Airport Certification Manual.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Amendment of Airport Certification Manual... CERTIFICATION OF AIRPORTS Airport Certification Manual § 139.205 Amendment of Airport Certification Manual. (a) Under § 139.3, the Regional Airports Division Manager may amend any Airport Certification...

  20. 14 CFR 91.139 - Emergency air traffic rules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Emergency air traffic rules. 91.139 Section...) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Flight Rules General § 91.139 Emergency air traffic rules. (a) This section prescribes a process for utilizing Notices to...

  1. 9 CFR 381.139 - Removal of official identifications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Removal of official identifications. 381.139 Section 381.139 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... removal of such articles from the containers. (b) No person shall alter, detach, deface, or destroy...

  2. 14 CFR 139.107 - Issuance of certificate.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Issuance of certificate. 139.107 Section 139.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... a safe airport operating environment in accordance with— (1) Any limitation that the...

  3. 21 CFR 139.155 - Enriched noodle products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... folic acid, and not less than 13 mg and not more than 16.5 mg of iron (Fe); (2) Each such food may also... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched noodle products. 139.155 Section 139.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  4. 21 CFR 139.155 - Enriched noodle products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... folic acid, and not less than 13 mg and not more than 16.5 mg of iron (Fe); (2) Each such food may also... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched noodle products. 139.155 Section 139.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  5. 32 CFR 935.139 - Motor vehicle operator qualifications.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Motor vehicle operator qualifications. 935.139... AND INSULAR REGULATIONS WAKE ISLAND CODE Motor Vehicle Code § 935.139 Motor vehicle operator qualifications. (a) No person may operate a privately owned motor vehicle on Wake Island unless he has an...

  6. 32 CFR 935.139 - Motor vehicle operator qualifications.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Motor vehicle operator qualifications. 935.139... AND INSULAR REGULATIONS WAKE ISLAND CODE Motor Vehicle Code § 935.139 Motor vehicle operator qualifications. (a) No person may operate a privately owned motor vehicle on Wake Island unless he has an...

  7. 14 CFR 139.337 - Wildlife hazard management.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Wildlife hazard management. 139.337 Section... AIRPORTS Operations § 139.337 Wildlife hazard management. (a) In accordance with its Airport Certification... alleviate wildlife hazards whenever they are detected. (b) In a manner authorized by the Administrator,...

  8. 14 CFR 139.337 - Wildlife hazard management.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Wildlife hazard management. 139.337 Section... AIRPORTS Operations § 139.337 Wildlife hazard management. (a) In accordance with its Airport Certification... alleviate wildlife hazards whenever they are detected. (b) In a manner authorized by the Administrator,...

  9. 14 CFR 139.337 - Wildlife hazard management.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Wildlife hazard management. 139.337 Section... AIRPORTS Operations § 139.337 Wildlife hazard management. (a) In accordance with its Airport Certification... alleviate wildlife hazards whenever they are detected. (b) In a manner authorized by the Administrator,...

  10. 14 CFR 139.337 - Wildlife hazard management.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Wildlife hazard management. 139.337 Section... AIRPORTS Operations § 139.337 Wildlife hazard management. (a) In accordance with its Airport Certification... alleviate wildlife hazards whenever they are detected. (b) In a manner authorized by the Administrator,...

  11. 14 CFR 139.337 - Wildlife hazard management.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Wildlife hazard management. 139.337 Section... AIRPORTS Operations § 139.337 Wildlife hazard management. (a) In accordance with its Airport Certification... alleviate wildlife hazards whenever they are detected. (b) In a manner authorized by the Administrator,...

  12. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  13. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  14. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Coverage for certain aliens. 435.139 Section 435... Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency medical condition, as defined in § 440.255(c) of this chapter, to those...

  15. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Coverage for certain aliens. 435.139 Section 435... ISLANDS, AND AMERICAN SAMOA Mandatory Coverage Mandatory Coverage of Certain Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency...

  16. 42 CFR 435.139 - Coverage for certain aliens.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Coverage for certain aliens. 435.139 Section 435... ISLANDS, AND AMERICAN SAMOA Mandatory Coverage Mandatory Coverage of Certain Aliens § 435.139 Coverage for certain aliens. The agency must provide services necessary for the treatment of an emergency...

  17. 22 CFR 1600.131-1600.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 2 2012-04-01 2009-04-01 true 1600.131-1600.139 Section 1600.131-1600.139 Foreign Relations JAPAN-UNITED STATES FRIENDSHIP COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE JAPAN-UNITED STATES FRIENDSHIP...

  18. 22 CFR 1600.131-1600.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false 1600.131-1600.139 Section 1600.131-1600.139 Foreign Relations JAPAN-UNITED STATES FRIENDSHIP COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE JAPAN-UNITED STATES FRIENDSHIP...

  19. 22 CFR 1600.131-1600.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true 1600.131-1600.139 Section 1600.131-1600.139 Foreign Relations JAPAN-UNITED STATES FRIENDSHIP COMMISSION ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE JAPAN-UNITED STATES FRIENDSHIP...

  20. 7 CFR 932.139 - Late payment and interest charges.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Late payment and interest charges. 932.139 Section 932.139 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE...

  1. 7 CFR 932.139 - Late payment and interest charges.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Late payment and interest charges. 932.139 Section 932.139 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE...

  2. 7 CFR 932.139 - Late payment and interest charges.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Late payment and interest charges. 932.139 Section 932.139 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  3. 7 CFR 932.139 - Late payment and interest charges.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Late payment and interest charges. 932.139 Section 932.139 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  4. 7 CFR 932.139 - Late payment and interest charges.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Late payment and interest charges. 932.139 Section 932.139 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE...

  5. 32 CFR 1906.131-1906.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false 1906.131-1906.139 Section 1906.131-1906.139 National Defense Other Regulations Relating to National Defense CENTRAL INTELLIGENCE AGENCY ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY THE CENTRAL INTELLIGENCE...

  6. Nanoparticulate cerium dioxide and cerium dioxide-titanium dioxide composite thin films on glass by aerosol assisted chemical vapour deposition

    NASA Astrophysics Data System (ADS)

    Qureshi, Uzma; Dunnill, Charles W.; Parkin, Ivan P.

    2009-11-01

    Two series of composite thin films were deposited on glass by aerosol assisted chemical vapour deposition (AACVD)—nanoparticulate cerium dioxide and nanoparticulate cerium dioxide embedded in a titanium dioxide matrix. The films were analysed by a range of techniques including UV-visible absorption spectroscopy, X-ray diffraction, scanning electron microscopy and energy dispersive analysis by X-rays. The AACVD prepared films showed the functional properties of photocatalysis and super-hydrophilicity. The CeO 2 nanoparticle thin films displaying photocatalysis and photo-induced hydrophilicity almost comparable to that of anatase titania.

  7. Hydrothermal preparation of fractal dendrites: Cerium carbonate hydroxide and cerium oxide

    SciTech Connect

    Wu Mingzai; Zhang Qihua; Liu Yanmei; Fang Qingqing; Liu Xiansong

    2009-06-03

    The surfactant-assisted hydrothermal route was used to prepare fractal dendrite cerium carbonate hydroxide (CeOHCO{sub 3}) microstructures. After annealing at 600 deg. C for 4 h, the products were transformed to CeO{sub 2}. The crystal structures of the two compounds were determined by X-ray diffraction (XRD). The morphologies and microstructures were characterized by field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). Room temperature photoluminescence (PL) showed that a strong ultraviolet emission at 336 nm was observed for CeOHCO{sub 3}, and that centered at 415 nm for CeO{sub 2} microstructures. Both of these emission peaks are different from those reported for CeOHCO{sub 3} and CeO{sub 2} with other shapes. In addition, the possible growth mechanism of dendrite CeOHCO{sub 3} microstructures and the role of surfactant polyvinyl pyrrolidone (PVP) were also investigated in this paper.

  8. Purification of cerium, neodymium and gadolinium for low background experiments

    NASA Astrophysics Data System (ADS)

    Boiko, R. S.; Barabash, A. S.; Belli, P.; Bernabei, R.; Cappella, F.; Cerulli, R.; Danevich, F. A.; Incicchitti, A.; Laubenstein, M.; Mokina, V. M.; Nisi, S.; Poda, D. V.; Polischuk, O. G.; Tretyak, V. I.

    2014-01-01

    Cerium, neodymium and gadolinium contain double beta active isotopes. The most interesting are 150Nd and 160Gd (promising for 0ν2β search), 136Ce (2β+ candidate with one of the highest Q2β). The main problem of compounds containing lanthanide elements is their high radioactive contamination by uranium, radium, actinium and thorium. The new generation 2β experiments require development of methods for a deep purification of lanthanides from the radioactive elements. A combination of physical and chemical methods was applied to purify cerium, neodymium and gadolinium. Liquid-liquid extraction technique was used to remove traces of Th and U from neodymium, gadolinium and for purification of cerium from Th, U, Ra and K. Co-precipitation and recrystallization methods were utilized for further reduction of the impurities. The radioactive contamination of the samples before and after the purification was tested by using ultra-low-background HPGe gamma spectrometry. As a result of the purification procedure the radioactive contamination of gadolinium oxide (a similar purification efficiency was reached also with cerium and neodymium oxides) was decreased from 0.12 Bq/kg to 0.007 Bq/kg in 228Th, from 0.04 Bq/kg to <0.006 Bq/kg in 226Ra, and from 0.9 Bq/kg to 0.04 Bq/kg in 40K. The purification methods are much less efficient for chemically very similar radioactive elements like actinium, lanthanum and lutetium.

  9. Cerium; crystal structure and position in the periodic table.

    PubMed

    Johansson, Börje; Luo, Wei; Li, Sa; Ahuja, Rajeev

    2014-09-17

    The properties of the cerium metal have intrigued physicists and chemists for many decades. In particular a lot of attention has been directed towards its high pressure behavior, where an isostructural volume collapse (γ phase → α phase) has been observed. Two main models of the electronic aspect of this transformation have been proposed; one where the 4f electron undergoes a change from being localized into an itinerant metallic state, and one where the focus is on the interaction between the 4f electron and the conduction electrons, often referred to as the Kondo volume collapse model. However, over the years it has been repeatedly questioned whether the cerium collapse really is isostructural. Most recently, detailed experiments have been able to remove this worrisome uncertainty. Therefore the isostructural aspect of the α-γ transition has now to be seriously addressed in the theoretical modeling, something which has been very much neglected. A study of this fundamental characteristic of the cerium volume collapse is made in present paper and we show that the localized [rlhar2 ] delocalized 4f electron picture provides an adequate description of this unique behavior. This agreement makes it possible to suggest that an appropriate crossroad position for cerium in The Periodic Table.

  10. Cerium; Crystal Structure and Position in The Periodic Table

    PubMed Central

    Johansson, Börje; Luo, Wei; Li, Sa; Ahuja, Rajeev

    2014-01-01

    The properties of the cerium metal have intrigued physicists and chemists for many decades. In particular a lot of attention has been directed towards its high pressure behavior, where an isostructural volume collapse (γ phase → α phase) has been observed. Two main models of the electronic aspect of this transformation have been proposed; one where the 4f electron undergoes a change from being localized into an itinerant metallic state, and one where the focus is on the interaction between the 4f electron and the conduction electrons, often referred to as the Kondo volume collapse model. However, over the years it has been repeatedly questioned whether the cerium collapse really is isostructural. Most recently, detailed experiments have been able to remove this worrisome uncertainty. Therefore the isostructural aspect of the α-γ transition has now to be seriously addressed in the theoretical modeling, something which has been very much neglected. A study of this fundamental characteristic of the cerium volume collapse is made in present paper and we show that the localized ⇌ delocalized 4f electron picture provides an adequate description of this unique behavior. This agreement makes it possible to suggest that an appropriate crossroad position for cerium in The Periodic Table. PMID:25227991

  11. 40 CFR 721.8657 - Cerium, hydroxy oleate propionate complexes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... complexes. 721.8657 Section 721.8657 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.8657 Cerium, hydroxy oleate propionate complexes. (a) Chemical substance..., hydroxy oleate propionate complexes (PMN P-99-0026) is subject to reporting under this section for...

  12. Electrode electrolyte interlayers containing cerium oxide for electrochemical fuel cells

    DOEpatents

    Borglum, Brian P.; Bessette, Norman F.

    2000-01-01

    An electrochemical cell is made having a porous fuel electrode (16) and a porous air electrode (13), with solid oxide electrolyte (15) therebetween, where the air electrode surface opposing the electrolyte has a separate, attached, dense, continuous layer (14) of a material containing cerium oxide, and where electrolyte (16) contacts the continuous oxide layer (14), without contacting the air electrode (13).

  13. Cerium as a surrogate in the plutonium immobilization waste form

    NASA Astrophysics Data System (ADS)

    Marra, James Christopher

    In the aftermath of the Cold War, approximately 50 tonnes (MT) of weapons useable plutonium (Pu) has been identified as excess. The U.S. Department of Energy (DOE) has decided that at least a portion of this material will be immobilized in a titanate-based ceramic for final disposal in a geologic repository. The baseline formulation was designed to produce a ceramic consisting primarily of a highly substituted pyrochlore with minor amounts of brannerite and hafnia-substituted rutile. Since development studies with actual actinide materials is difficult, surrogates have been used to facilitate testing. Cerium has routinely been used as an actinide surrogate in actinide chemistry and processing studies. Although cerium appeared as an adequate physical surrogate for powder handling and general processing studies, cerium was found to act significantly different from a chemical perspective in the Pu ceramic form. The reduction of cerium at elevated temperatures caused different reaction paths toward densification of the respective forms resulting in different phase assemblages and microstructural features. Single-phase fabrication studies and cerium oxidation state analyses were performed to further quantify these behavioral differences. These studies indicated that the major phases in the final phase assemblages contained point defects likely leading to their stability. Additionally, thermochemical arguments predicted that the predominant pyrochlore phase in the ceramic was metastable. The apparent metastabilty associated with primary phase in the Pu ceramic form indicated that additional studies must be performed to evaluate the thermodynamic properties of these compounds. Moreover, the metastability of this predominant phase must be considered in assessment of long-term behavior (e.g. radiation stability) of this ceramic.

  14. [Determination of silver and cerium in the liver and the kidney from a severely burned infant treated with silver sulfadiazine and cerium nitrate].

    PubMed

    Hirakawa, K

    1983-02-01

    Silver and cerium in the liver and the kidney from severely burned infant were analyzed by neutron activation method. The patient was treated topically with cerium nitrate/silver sulfadiazine cream and cerium nitrate solution for 3 months. Then, the treatment with these drugs was stopped because of abdominal distention. The patient died 1 month after the cessation of the treatment with these drugs. The tissue specimens, blank liver sample and reference standards were irradiated with TRIGA MARK II Reactor of Rikkyo University. About 1 month after the irradiation, the activities were measured with a Ge(Li) detector coupled to a 4096 channel pulse height analyzer. A large amount of silver was detected both in the liver and in the kidney and a trace of cerium only in the liver. A considerable amount of silver was detected in the liver and its quantity was about 1600 times more than that of normal livers reported by Hamilton, Minski and Cleary (1972-73). Neither silver nor cerium were detected in the blank liver. These results suggest that prolonged topical chemotherapy of cerium nitrate/silver sulfadiazine cream and cerium nitrate solution for the extensive burn injuries causes considerable absorption of silver and cerium into the liver and the kidney. PMID:6867381

  15. Fundamental aspects of regenerative cerium oxide nanoparticles and their applications in nanobiotechnology

    NASA Astrophysics Data System (ADS)

    Patil, Swanand D.

    Cerium oxide has been used extensively for various applications over the past two decades. The use of cerium oxide nanoparticles is beneficial in present applications and can open avenues for future applications. The present study utilizes the microemulsion technique to synthesize uniformly distributed cerium oxide nanoparticles. The same technique was also used to synthesize cerium oxide nanoparticles doped with trivalent elements (La and Nd). The fundamental study of cerium oxide nanoparticles identified variations in properties as a function of particle size and also due to doping with trivalent elements (La and Nd). It was found that the lattice parameter of cerium oxide nanoparticles increases with decrease in particle size. Also Raman allowed mode shift to lower energies and the peak at 464 cm-1 becomes broader and asymmetric. The size dependent changes in cerium oxide were correlated to increase in oxygen vacancy concentration in the cerium oxide lattice. The doping of cerium oxide nanoparticles with trivalent elements introduces more oxygen vacancies and expands the cerium oxide lattice further (in addition to the lattice expansion due to the size effect). The lattice expansion is greater for La-doped cerium oxide nanoparticles compared to Nd-doping due to the larger ionic radius of La compared to Nd, the lattice expansion is directly proportional to the dopant concentration. The synthesized cerium oxide nanoparticles were used to develop an electrochemical biosensor of hydrogen peroxide (H2O2). The sensor was useful to detect H2O2 concentrations as low as 1muM in water. Also the preliminary testing of the sensor on tomato stem and leaf extracts indicated that the sensor can be used in practical applications such as plant physiological studies etc. The nanomolar concentrations of cerium oxide nanoparticles were also found to be useful in decreasing ROS (reactive oxygen species) mediated cellular damages in various in vitro cell cultures. Cerium oxide

  16. 45 CFR 1706.131-1706.139 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE §§ 1706.131-1706.139...

  17. 8. VIEW SOUTHWEST, INTERIOR VIEW, WIND TUNNEL 139 Naval ...

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

    8. VIEW SOUTHWEST, INTERIOR VIEW, WIND TUNNEL 139 - Naval Surface Warfare Center, Subsonic Wind Tunnel Building, Bounded by Clara Barton Parkway & McArthur Boulevard, Silver Spring, Montgomery County, MD

  18. 21 CFR 139.125 - Vegetable macaroni products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... optional ingredient gum gluten (§ 139.110(a)(5)) is added, the quantity is such that the protein derived therefrom, together with the protein derived from the semolina, durum flour, farina, flour or...

  19. 21 CFR 139.125 - Vegetable macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... optional ingredient gum gluten (§ 139.110(a)(5)) is added, the quantity is such that the protein derived therefrom, together with the protein derived from the semolina, durum flour, farina, flour or...

  20. 21 CFR 139.125 - Vegetable macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... optional ingredient gum gluten (§ 139.110(a)(5)) is added, the quantity is such that the protein derived therefrom, together with the protein derived from the semolina, durum flour, farina, flour or...

  1. 21 CFR 139.125 - Vegetable macaroni products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... optional ingredient gum gluten (§ 139.110(a)(5)) is added, the quantity is such that the protein derived therefrom, together with the protein derived from the semolina, durum flour, farina, flour or...

  2. 21 CFR 139.125 - Vegetable macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... optional ingredient gum gluten (§ 139.110(a)(5)) is added, the quantity is such that the protein derived therefrom, together with the protein derived from the semolina, durum flour, farina, flour or...

  3. 21 CFR 139.115 - Enriched macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... not more than 1.2 mg of folic acid, and not less than 13 mg and not more than 16.5 mg of iron (Fe); (2... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched macaroni products. 139.115 Section 139.115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  4. 21 CFR 139.122 - Enriched nonfat milk macaroni products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... than 0.9 mg and not more than 1.2 mg of folic acid, and not less than 13 mg and not more than 16.5 mg... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Enriched nonfat milk macaroni products. 139.122 Section 139.122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  5. 21 CFR 139.122 - Enriched nonfat milk macaroni products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... than 0.9 mg and not more than 1.2 mg of folic acid, and not less than 13 mg and not more than 16.5 mg... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Enriched nonfat milk macaroni products. 139.122 Section 139.122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  6. 21 CFR 139.115 - Enriched macaroni products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... not more than 1.2 mg of folic acid, and not less than 13 mg and not more than 16.5 mg of iron (Fe); (2... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched macaroni products. 139.115 Section 139.115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  7. Study of cerium diffusion in undoped lithium-6 enriched glass with Rutherford backscattering spectrometry

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaodong; Moore, Michael E.; Lee, Kyung-Min; Lukosi, Eric D.; Hayward, Jason P.

    2016-07-01

    Undoped lithium-6 enriched glasses coated with pure cerium (99.9%) with a gold protection layer on top were heated at three different temperatures (500, 550, and 600 °C) for varied durations (1, 2, and 4 h). Diffusion profiles of cerium in such glasses were obtained with the conventional Rutherford backscattering technique. Through fitting the diffusion profiles with the thin-film solution of Fick's second law, diffusion coefficients of cerium with different annealing temperatures and durations were solved. Then, the activation energy of cerium for the diffusion process in the studied glasses was found to be 114 kJ/mol with the Arrhenius equation.

  8. Isomorphic phase transformation in shocked cerium using molecular dynamics

    SciTech Connect

    Dupont, Virginie; Germann, Timothy C; Chen, Shao - Ping

    2010-08-12

    Cerium (Ce) undergoes a significant ({approx}16%) volume collapse associated with an isomorphic fcc-fcc phase transformation when subject to compressive loading. We present here a new Embedded Atom Method (EAM) potential for Cerium that models two minima for the two fcc phases. We show results from its use in Molecular Dynamics (MD) simulations of Ce samples subjected to shocks with pressures ranging from 0.5 to 25 GPa. A split wave structure is observed, with an elastic precursor followed by a plastic wave. The plastic wave causes the expected fcc-fcc phase transformation. Comparisons to experiments and MD simulations on Cesium (Cs) indicate that three waves could be observed. The construction of the EAM potential may be the source of the difference.

  9. Liquid-phase oxidation of cyclohexanone over cerium oxide catalyst

    SciTech Connect

    Shen, H.C. ); Weng, H.S. )

    1990-05-01

    Catalytic oxidation of cyclohexanone in the liquid phase with glacial acetic acid as the solvent over cerium oxide was studied between 5 and 15 atm and 98 and 118 {degrees} C in a batch reactor. The products were adipic acid, glutaric acid, succinic acid, caprolactone, carbon oxides, etc. The reaction undergoes a short induction period prior to a rapid reaction regime. In both regimes, the reaction is independent of oxygen pressure when the system pressure is above 10 atm. The induction period is inversely proportional to both of the catalyst weight and cyclohexanone concentration.During the rapid reaction regime, the reaction rate was found to be proportional to the 0.5 power of the catalyst weight and to the 1.5 power of the cyclohexanone concentration. Reaction mechanisms and rate expressions are proposed. The carbon oxides produced in this study were much lower than those previously reported. The cerium oxide catalyst is stable during the reaction.

  10. Transmembrane protein 139 (TMEM139) interacts with human kidney isoform of anion exchanger 1 (kAE1).

    PubMed

    Nuiplot, Nalin-On; Junking, Mutita; Duangtum, Natapol; Khunchai, Sasiprapa; Sawasdee, Nunghathai; Yenchitsomanus, Pa-Thai; Akkarapatumwong, Varaporn

    2015-08-01

    Human kidney anion exchanger 1 (kAE1) mediates Cl(-)/HCO3(-) exchanges at the basolateral membrane of the acid-secreting α-intercalated cells. Mutations in SLC4A1 gene encoding kAE1 are associated with distal renal tubular acidosis (dRTA). Several studies have shown that impaired trafficking of the mutant kAE1 is an important molecular mechanism underlying the pathogenesis of dRTA. Proteins involved in kAE1 trafficking were identified but the mechanism resulting in dRTA remained unclear. Thus, this study attempted to search for additional proteins interacting with C-terminal of kAE1 (Ct-kAE1) and involved in kAE1 trafficking to cell membrane. Transmembrane protein 139 (TMEM139) was identified as a protein interacting with Ct-kAE1 by yeast two-hybrid screening. The interaction between kAE1 and TMEM139 was confirmed by affinity co-purification, co-immunoprecipitation (co-IP) and yellow fluorescent protein (YFP)-based protein fragment complementation assay (PCA). In addition, flow cytometry results showed that suppression of endogenous TMEM139 by small interfering RNA (siRNA) and over-expression of TMEM139 in HEK293T cells could reduce and increase membrane localization of kAE1, respectively. The presented data demonstrate that TMEM139 interacts with kAE1 and promotes its intracellular trafficking. PMID:26049106

  11. Engineered cerium oxide nanoparticles: Effects on bacterial growth and viability

    SciTech Connect

    Pelletier, Dale A; Suresh, Anil K; Holton, Gregory A; McKeown, Catherine K; Wang, Wei; Gu, Baohua; Mortensen, Ninell P; Allison, David P; Joy, David Charles; Allison, Martin R; Brown, Steven D; Phelps, Tommy Joe; Doktycz, Mitchel John

    2010-01-01

    Interest in engineered nanostructures has risen in recent years due to their use in energy conservation strategies and biomedicine. To ensure prudent development and use of nanomaterials, the fate and effects of such engineered structures on the environment should be understood. Interactions of nanomaterials with environmental microorganisms are inevitable, but the general consequences of such interactions remain unclear. Further, standardized methods for assessing such interactions are lacking. Therefore, we have initiated a multianalytical approach to understand the interactions of synthesized nanoparticles with bacterial systems. These efforts are focused initially on cerium oxide nanoparticles and model bacteria in order to evaluate characterization procedures and the possible fate of such materials in the environment. In this study the effects of cerium oxide nanoparticles on the growth and viability of Gram-negative Escherichia coli and Shewanella oneidensis, a metal-reducing bacteria, and Gram-positive Bacillus subtilis were examined relative to particle size, growth media, pH, and dosage. A hydrothermal based synthesis procedure was used to prepare cerium oxide nanoparticles of defined sizes in order to eliminate complications originating from the use of organic solvents and surfactants. Bactericidal effects were determined by minimum inhibitory concentration, colony forming units, disc diffusion tests and Live/Dead assays. In growth inhibition experiments involving E. coli and B. subtilis, a clear strain and size-dependent inhibition was observed. S. oneidensis appeared to be unaffected by the cerium oxide nanoparticles. Transmission electron microscopy along with microarray-based transcriptional profiling have been used to understand the response mechanism of the bacteria. The use of multiple analytical approaches adds confidence to toxicity assessments while the use of different bacterial systems highlights the potential wide-ranging effects of

  12. Monomers, Dimers, and Helices: Complexities of Cerium and Plutonium Phenanthrolinecarboxylates.

    PubMed

    Cary, Samantha K; Ferrier, Maryline G; Baumbach, Ryan E; Silver, Mark A; Lezama Pacheco, Juan; Kozimor, Stosh A; La Pierre, Henry S; Stein, Benjamin W; Arico, Alexandra A; Gray, Danielle L; Albrecht-Schmitt, Thomas E

    2016-05-01

    The reaction of Ce(III) or Pu(III) with 1,10-phenanthroline-2,9-dicarboxylic acid (PDAH2) results in the formation of new f-element coordination complexes. In the case of cerium, Ce(PDA)(H2O)2Cl·H2O (1) or [Ce(PDAH)(PDA)]2[Ce(PDAH)(PDA)] (2) was isolated depending on the Ce/ligand ratio in the reaction. The structure of 2 is composed of two distinct substructures that are constructed from the same monomer. This monomer is composed of a Ce(III) cation bound by one PDA(2-) dianionic ligand and one PDAH(-) monoanionic ligand, both of which are tetradentate. Bridging by the carboxylate moieties leads to either [Ce(PDAH)(PDA)]2 dimers or [Ce(PDAH)(PDA)]1∞ helical chains. For plutonium, Pu(PDA)2 (3) was the only product isolated regardless of the Pu/ligand ratio employed in the reaction. During the reaction of plutonium with PDAH2, Pu(III) is oxidized to Pu(IV), generating 3. This assignment is consistent with structural metrics and the optical absorption spectrum. Ambiguity in the assignment of the oxidation state of cerium in 1 and 2 from UV-vis-near-IR spectra invoked the use of Ce L3,2-edge X-ray absorption near-edge spectroscopy, magnetic susceptibility, and heat capacity measurements. These experiments support the assignment of Ce(III) in both compounds. The bond distances and coordination numbers are also consistent with these assignments. 3 contains 8-coordinate Pu(IV), whereas the cerium centers in 1 and 2 are 9- and/or 10-coordinate, which correlates with the increased size of Ce(III) versus Pu(IV). Taken together, these data provide an example of a system where the differences in the redox behavior between these f elements creates more complex chemistry with cerium than with plutonium. PMID:27070401

  13. Fungus mediated synthesis of biomedically important cerium oxide nanoparticles

    SciTech Connect

    Khan, Shadab Ali; Ahmad, Absar

    2013-10-15

    Graphical abstract: - Highlights: • First time biological synthesis of cerium oxide oxide nanoparticles using fungus Humicola sp. • Complete characterization of cerium oxide nanoparticles. • Biosynthesis of naturally protein capped, luminescent and water dispersible CeO{sub 2} nanoparticles. • Biosynthesized CeO{sub 2} nanoparticles can be used for many biomedical applications. - Abstract: Nanomaterials can be synthesized by chemical, physical and the more recently discovered biological routes. The biological routes are advantageous over the chemical and physical ones as unlike these, the biological synthesis protocols occur at ambient conditions, are cheap, non-toxic and eco-friendly. Although purely biological and bioinspired methods for the synthesis of nanomaterials are environmentally benign and energy conserving processes, their true potential has not been explored yet and attempts are being made to extend the formation of technologically important nanoparticles using microorganisms like fungi. Though there have been reports on the biosynthesis of oxide nanoparticles by our group in the past, no attempts have been made to employ fungi for the synthesis of nanoparticles of rare earth metals or lanthanides. Here we report for the first time, the bio-inspired synthesis of biomedically important cerium oxide (CeO{sub 2}) nanoparticles using the thermophilic fungus Humicola sp. The fungus Humicola sp. when exposed to aqueous solutions of oxide precursor cerium (III) nitrate hexahydrate (CeN{sub 3}O{sub 9}·6H{sub 2}O) results in the extracellular formation of CeO{sub 2} nanoparticles containing Ce (III) and Ce (IV) mixed oxidation states, confirmed by X-ray Photoemission Spectroscopy (XPS). The formed nanoparticles are naturally capped by proteins secreted by the fungus and thus do not agglomerate, are highly stable, water dispersible and are highly fluorescent as well. The biosynthesized nanoparticles were characterized by UV–vis spectroscopy

  14. Optical Response of Shocked Cerium-Doped Lutetium Oxyorthosilicate

    SciTech Connect

    G. D. Stevens

    2003-03-01

    Shock experiments were performed in order to characterize the triboluminescent signature of cerium-doped lutetium oxyorthosilicate (LSO:Ce). This material shows prompt, nano-second timescale light emission when driven by explosive detonation. When properly applied to a surface, it may be used as a shock arrival sensor, and also for imaging the propagation of a shock front. Triboluminescent rise times, spectral content, and spatial resolution measurements are presented.

  15. Antibacterial Activity of Polymer Coated Cerium Oxide Nanoparticles

    PubMed Central

    Shah, Vishal; Shah, Shreya; Shah, Hirsh; Rispoli, Fred J.; McDonnell, Kevin T.; Workeneh, Selam; Karakoti, Ajay; Kumar, Amit; Seal, Sudipta

    2012-01-01

    Cerium oxide nanoparticles have found numerous applications in the biomedical industry due to their strong antioxidant properties. In the current study, we report the influence of nine different physical and chemical parameters: pH, aeration and, concentrations of MgSO4, CaCl2, KCl, natural organic matter, fructose, nanoparticles and Escherichia coli, on the antibacterial activity of dextran coated cerium oxide nanoparticles. A least-squares quadratic regression model was developed to understand the collective influence of the tested parameters on the anti-bacterial activity and subsequently a computer-based, interactive visualization tool was developed. The visualization allows us to elucidate the effect of each of the parameters in combination with other parameters, on the antibacterial activity of nanoparticles. The results indicate that the toxicity of CeO2 NPs depend on the physical and chemical environment; and in a majority of the possible combinations of the nine parameters, non-lethal to the bacteria. In fact, the cerium oxide nanoparticles can decrease the anti-bacterial activity exerted by magnesium and potassium salts. PMID:23110109

  16. Synthesis and characterization of polyvinylpyrrolidone coated cerium oxide nanoparticles.

    PubMed

    Merrifield, Ruth C; Wang, Zhi Wei; Palmer, Richard E; Lead, Jamie R

    2013-01-01

    There is a pressing need for the development of standard and reference nanomaterials for environmental nanoscience and nanotoxicology. To that aim, suspensions of polyvinylpyrrolidone (PVP)-coated ceria nanoparticles (NPs) were produced. Four differently sized monodispersed samples were produced by using different PVP chain lengths. The chemical and physical properties of these NPs were characterized as prepared and in different ecotoxicology exposure media. Dynamic light scattering analysis showed that the samples were monodispersed, with an unchanged size when suspended in the different media over a 72 h period. Electron microscopy confirmed this and revealed that the larger (ca. 20 nm) particles were aggregates composed of the smaller individual particles (4-5 nm). Electron energy loss spectroscopy (EELS) showed that the smallest and largest samples were composed almost entirely of cerium(III) oxide, with only small amounts of cerium(IV) present in the largest sample. Dissolved cerium concentrations in media were low and constant, showing that the NPs did not dissolve over time. The simple synthesis of the these NPs and their physical and chemical stability in different environmental conditions make them potentially suitable for use as reference materials for (eco)toxicology and surface water environmental studies.

  17. Jet formation in cerium metal to examine material strength

    SciTech Connect

    Jensen, B. J. Cherne, F. J.; Prime, M. B.; Yeager, J. D.; Ramos, K. J.; Hooks, D. E.; Cooley, J. C.; Dimonte, G.; Fezzaa, K.; Iverson, A. J.; Carlson, C. A.

    2015-11-21

    Examining the evolution of material properties at extreme conditions advances our understanding of numerous high-pressure phenomena from natural events like meteorite impacts to general solid mechanics and fluid flow behavior. Recent advances in synchrotron diagnostics coupled with dynamic compression platforms have introduced new possibilities for examining in-situ, spatially resolved material response with nanosecond time resolution. In this work, we examined jet formation from a Richtmyer-Meshkov instability in cerium initially shocked into a transient, high-pressure phase, and then released to a low-pressure, higher-temperature state. Cerium's rich phase diagram allows us to study the yield stress following a shock induced solid-solid phase transition. X-ray imaging was used to obtain images of jet formation and evolution with 2–3 μm spatial resolution. From these images, an analytic method was used to estimate the post-shock yield stress, and these results were compared to continuum calculations that incorporated an experimentally validated equation-of-state (EOS) for cerium coupled with a deviatoric strength model. Reasonable agreement was observed between the calculations and the data illustrating the sensitivity of jet formation on the yield stress values. The data and analysis shown here provide insight into material strength during dynamic loading which is expected to aid in the development of strength aware multi-phase EOS required to predict the response of matter at extreme conditions.

  18. Induction of pulmonary fibrosis by cerium oxide nanoparticles

    SciTech Connect

    Ma, Jane Y.; Mercer, Robert R.; Barger, Mark; Schwegler-Berry, Diane; Scabilloni, James; Ma, Joseph K.; Castranova, Vincent

    2012-08-01

    Cerium compounds have been used as a diesel engine catalyst to lower the mass of diesel exhaust particles, but are emitted as cerium oxide (CeO{sub 2}) nanoparticles in the diesel exhaust. In a previous study, we have demonstrated a wide range of CeO{sub 2}-induced lung responses including sustained pulmonary inflammation and cellular signaling that could lead to pulmonary fibrosis. In this study, we investigated the fibrogenic responses induced by CeO{sub 2} in a rat model at various time points up to 84 days post-exposure. Male Sprague Dawley rats were exposed to CeO{sub 2} by a single intratracheal instillation. Alveolar macrophages (AM) were isolated by bronchial alveolar lavage (BAL). AM-mediated cellular responses, osteopontin (OPN) and transform growth factor (TGF)-β1 in the fibrotic process were investigated. The results showed that CeO{sub 2} exposure significantly increased fibrotic cytokine TGF-β1 and OPN production by AM above controls. The collagen degradation enzymes, matrix metalloproteinase (MMP)-2 and -9 and the tissue inhibitor of MMP were markedly increased in the BAL fluid at 1 day- and subsequently declined at 28 days after exposure, but remained much higher than the controls. CeO{sub 2} induced elevated phospholipids in BAL fluid and increased hydroxyproline content in lung tissue in a dose- and time-dependent manner. Immunohistochemical analysis showed MMP-2, MMP-9 and MMP-10 expressions in fibrotic regions. Morphological analysis noted increased collagen fibers in the lungs exposed to a single dose of 3.5 mg/kg CeO{sub 2} and euthanized at 28 days post-exposure. Collectively, our studies show that CeO{sub 2} induced fibrotic lung injury in rats, suggesting it may cause potential health effects. -- Highlights: ► Cerium oxide exposure significantly affected the following parameters in the lung. ► Induced fibrotic cytokine OPN and TGF-β1 production and phospholipidosis. ► Caused imbalance of the MMP-9/ TIMP-1 ratio that favors fibrosis

  19. Equation of state of quartz glass and cerium in their abnormal compressibility range

    NASA Astrophysics Data System (ADS)

    Molodets, A. M.

    2016-09-01

    In this work, the semiempirical equation of state of quartz glass and polycrystalline γ-cerium are plotted and verified at the compressive pressures to 3 GPa. The proposed equations are shown to uniformly describe the thermophysical and physicomechanical properties of quartz glass and polycrystalline γ-cerium at their abnormal compressibility in compression. The room isotherms of these materials are discussed, as well.

  20. Cerium doped red mud catalytic ozonation for bezafibrate degradation in wastewater: Efficiency, intermediates, and toxicity.

    PubMed

    Xu, Bingbing; Qi, Fei; Sun, Dezhi; Chen, Zhonglin; Robert, Didier

    2016-03-01

    In this study, the performance of bezafibrate (BZF) degradation and detoxification in the aqueous phase using cerium-modified red mud (RM) catalysts prepared using different cerium sources and synthesis methods were evaluated. Experimental results showed that the surface cerium modification was responsible for the development of the catalytic activity of RM and this was influenced by the cerium source and the synthesis method. Catalyst prepared from cerium (IV) by precipitation was found to show the best catalytic activity in BZF degradation and detoxification. Reactive oxygen species including peroxides, hydroxyl radicals, and super oxide ions were identified in all reactions and we proposed the corresponding catalytic reaction mechanism for each catalyst that prepared from different cerium source and method. This was supported by the intermediates profiles that were generated upon BZF degradation. The surface and the structural properties of cerium-modified RM were characterized in detail by several analytical methods. Two interesting findings were made: (1) the surface texture (specific surface area and mesoporous volume) influenced the catalytic reaction pathway; and (2) Ce(III) species and oxygen vacancies were generated on the surface of the catalyst after cerium modification. This plays an important role in the development of the catalytic activity. PMID:26706928

  1. Reactions of carbonyl compounds with Grignard reagents in the presence of cerium chloride

    SciTech Connect

    Imamoto, Tsuneo; Takiyama, Nobuyuki; Nakamura, Kimikazu; Hatajima, Toshihiko; Kamiya, Yasuo )

    1989-06-07

    The addition of Grignard reagents to ketones is significantly enhanced by cerium chloride with remarkable suppression of side reactions, particularly enolization. Some esters, which are prone to side reactions, also react readily with Grignard reagents in the presence of cerium chloride to give normal reaction products in reasonable to high yields.

  2. Hydrocarbon-based polymer electrolyte cerium composite membranes for improved proton exchange membrane fuel cell durability

    NASA Astrophysics Data System (ADS)

    Lee, Hyejin; Han, Myungseong; Choi, Young-Woo; Bae, Byungchan

    2015-11-01

    Hydrocarbon-based cerium composite membranes were prepared for proton exchange membrane fuel cell applications to increase oxidative stability. Different amounts of cerium ions were impregnated in sulfonated poly(arylene ether sulfone) (SPES) membranes and their physicochemical properties were investigated according to the cerium content. Field-emission scanning electron microscopy and inductively coupled plasma analyses confirmed the presence of cerium ions in the composite membranes and 1H NMR indicated the successful coordination of sulfonic acid groups with the metal ions. Increasing amounts of cerium ions resulted in decreases in the proton conductivity and water uptake, but enhanced oxidative stability. The oxidative stability of the composite membranes was proven via a hydrogen peroxide exposure experiment which mimicked fuel cell operating conditions. In addition, more than 2200 h was achieved with the composite membrane under in situ accelerated open circuit voltage (OCV) durability testing (DOE protocol), whereas the corresponding pristine SPES membrane attained only 670 h.

  3. Tuning Reactivity and Electronic Properties through Ligand Reorganization within a Cerium Heterobimetallic Framework

    SciTech Connect

    Robinson, Jerome R.; Gordon, Zachary; Booth, Corwin H.; Carroll, Patrick J.; Walsh, Patrick J.; Schelter, Eric J.

    2014-06-24

    Cerium compounds have played vital roles in organic, inorganic, and materials chemistry due to their reversible redox chemistry between trivalent and tetravalent oxidation states. However, attempts to rationally access molecular cerium complexes in both oxidation states have been frustrated by unpredictable reactivity in cerium(III) oxidation chemistry. Such oxidation reactions are limited by steric saturation at the metal ion, which can result in high energy activation barriers for electron transfer. An alternative approach has been realized using a rare earth/alkali metal/1,1'-BINOLate (REMB) heterobimetallic framework, which uses redox-inactive metals within the secondary coordination sphere to control ligand reorganization. The rational syntheses of functionalized cerium(IV) products and a mechanistic examination of the role of ligand reorganization in cerium(III) oxidation are presented.

  4. Effects of uncoated and citric acid coated cerium oxide nanoparticles, bulk cerium oxide, cerium acetate, and citric acid on tomato plants.

    PubMed

    Barrios, Ana Cecilia; Rico, Cyren M; Trujillo-Reyes, Jesica; Medina-Velo, Illya A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2016-09-01

    Little is known about the physiological and biochemical responses of plants exposed to surface modified nanomaterials. In this study, tomato (Solanum lycopersicum L.) plants were cultivated for 210days in potting soil amended with uncoated and citric acid coated cerium oxide nanoparticles (nCeO2, CA+nCeO2) bulk cerium oxide (bCeO2), and cerium acetate (CeAc). Millipore water (MPW), and citric acid (CA) were used as controls. Physiological and biochemical parameters were measured. At 500mg/kg, both the uncoated and CA+nCeO2 increased shoot length by ~9 and ~13%, respectively, while bCeO2 and CeAc decreased shoot length by ~48 and ~26%, respectively, compared with MPW (p≤0.05). Total chlorophyll, chlo-a, and chlo-b were significantly increased by CA+nCeO2 at 250mg/kg, but reduced by bCeO2 at 62.5mg/kg, compared with MPW. At 250 and 500mg/kg, nCeO2 increased Ce in roots by 10 and 7 times, compared to CA+nCeO2, but none of the treatments affected the Ce concentration in above ground tissues. Neither nCeO2 nor CA+nCeO2 affected the homeostasis of nutrient elements in roots, stems, and leaves or catalase and ascorbate peroxidase in leaves. CeAc at 62.5 and 125mg/kg increased B (81%) and Fe (174%) in roots, while at 250 and 500mg/kg, increased Ca in stems (84% and 86%, respectively). On the other hand, bCeO2 at 62.5 increased Zn (152%) but reduced P (80%) in stems. Only nCeO2 at 62.5mg/kg produced higher total number of tomatoes, compared with control and the rest of the treatments. The surface coating reduced Ce uptake by roots but did not affect its translocation to the aboveground organs. In addition, there was no clear effect of surface coating on fruit production. To our knowledge, this is the first study comparing the effects of coated and uncoated nCeO2 on tomato plants.

  5. Effects of uncoated and citric acid coated cerium oxide nanoparticles, bulk cerium oxide, cerium acetate, and citric acid on tomato plants.

    PubMed

    Barrios, Ana Cecilia; Rico, Cyren M; Trujillo-Reyes, Jesica; Medina-Velo, Illya A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2016-09-01

    Little is known about the physiological and biochemical responses of plants exposed to surface modified nanomaterials. In this study, tomato (Solanum lycopersicum L.) plants were cultivated for 210days in potting soil amended with uncoated and citric acid coated cerium oxide nanoparticles (nCeO2, CA+nCeO2) bulk cerium oxide (bCeO2), and cerium acetate (CeAc). Millipore water (MPW), and citric acid (CA) were used as controls. Physiological and biochemical parameters were measured. At 500mg/kg, both the uncoated and CA+nCeO2 increased shoot length by ~9 and ~13%, respectively, while bCeO2 and CeAc decreased shoot length by ~48 and ~26%, respectively, compared with MPW (p≤0.05). Total chlorophyll, chlo-a, and chlo-b were significantly increased by CA+nCeO2 at 250mg/kg, but reduced by bCeO2 at 62.5mg/kg, compared with MPW. At 250 and 500mg/kg, nCeO2 increased Ce in roots by 10 and 7 times, compared to CA+nCeO2, but none of the treatments affected the Ce concentration in above ground tissues. Neither nCeO2 nor CA+nCeO2 affected the homeostasis of nutrient elements in roots, stems, and leaves or catalase and ascorbate peroxidase in leaves. CeAc at 62.5 and 125mg/kg increased B (81%) and Fe (174%) in roots, while at 250 and 500mg/kg, increased Ca in stems (84% and 86%, respectively). On the other hand, bCeO2 at 62.5 increased Zn (152%) but reduced P (80%) in stems. Only nCeO2 at 62.5mg/kg produced higher total number of tomatoes, compared with control and the rest of the treatments. The surface coating reduced Ce uptake by roots but did not affect its translocation to the aboveground organs. In addition, there was no clear effect of surface coating on fruit production. To our knowledge, this is the first study comparing the effects of coated and uncoated nCeO2 on tomato plants. PMID:26672385

  6. 7 CFR 1150.139 - Powers of the Board.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.139 Powers of the Board. The Board shall have... plans or projects to promote the use of fluid milk and dairy products as well as projects for...

  7. 7 CFR 1150.139 - Powers of the Board.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.139 Powers of the Board. The Board shall have... plans or projects to promote the use of fluid milk and dairy products as well as projects for...

  8. 7 CFR 1150.139 - Powers of the Board.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.139 Powers of the Board. The Board shall have... plans or projects to promote the use of fluid milk and dairy products as well as projects for...

  9. 7 CFR 1150.139 - Powers of the Board.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.139 Powers of the Board. The Board shall have... plans or projects to promote the use of fluid milk and dairy products as well as projects for...

  10. 7 CFR 1150.139 - Powers of the Board.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order National Dairy Promotion and Research Board § 1150.139 Powers of the Board. The Board shall have... plans or projects to promote the use of fluid milk and dairy products as well as projects for...

  11. 7 CFR 58.139 - Record of tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.139 Record of tests. Accurate records listing the results of quality and drug residue tests... and drug residue test records (§ 58.148(a), (e) and (g)) for any producer transferring milk...

  12. 7 CFR 58.139 - Record of tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.139 Record of tests. Accurate records listing the results of quality and drug residue tests... and drug residue test records (§ 58.148(a), (e) and (g)) for any producer transferring milk...

  13. 7 CFR 58.139 - Record of tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.139 Record of tests. Accurate records listing the results of quality and drug residue tests... and drug residue test records (§ 58.148(a), (e) and (g)) for any producer transferring milk...

  14. 7 CFR 58.139 - Record of tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.139 Record of tests. Accurate records listing the results of quality and drug residue tests... and drug residue test records (§ 58.148(a), (e) and (g)) for any producer transferring milk...

  15. 7 CFR 58.139 - Record of tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Milk § 58.139 Record of tests. Accurate records listing the results of quality and drug residue tests... and drug residue test records (§ 58.148(a), (e) and (g)) for any producer transferring milk...

  16. 14 CFR 139.205 - Amendment of Airport Certification Manual.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... TRANSPORTATION (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS...) Under § 139.3, the Regional Airports Division Manager may amend any Airport Certification Manual... Airports Division Manager's own initiative, if the Regional Airports Division Manager determines...

  17. 139. ARAIII Index of drwaings of gascooled reactor experiment buildings. ...

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

    139. ARA-III Index of drwaings of gas-cooled reactor experiment buildings. Aerojet-general 880-area/GCRE-100. Date: February 1958. Ineel index code no. 063-9999-80-013-102505. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  18. 45 CFR 1706.131-1706.139 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE §§ 1706.131-1706.139...

  19. 45 CFR 1706.131-1706.139 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE §§ 1706.131-1706.139...

  20. 45 CFR 1706.131-1706.139 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE ENFORCEMENT OF NONDISCRIMINATION ON THE BASIS OF HANDICAP IN PROGRAMS OR ACTIVITIES CONDUCTED BY NATIONAL COMMISSION ON LIBRARIES AND INFORMATION SCIENCE §§ 1706.131-1706.139...

  1. Thermal Signatures of The Kondo Volume Collapse in Cerium

    SciTech Connect

    Lipp, M; Jackson, D; Cynn, H; Aracne, C; Evans, W; McMahan, A

    2008-05-23

    X-ray diffraction measurements of cerium in the vicinity of the isostructural {gamma}-{alpha} transition have been performed with high precision and accuracy from room temperature to almost 800 K. The disputed location of the critical point has been found to occur at 1.5 {+-} 0.1 GPa and 480 {+-} 10 K. The data is well fit by the Kondo volume collapse model plus a quasiharmonic representation of the phonons. The resultant free energy is validated against data for the thermodynamic Grueneisen parameter, and beyond the dominant spin fluctuation contribution, indicates a dramatic change in the lattice Grueneisen parameter across the transition.

  2. Identification of the Charge Carriers in Cerium Phosphate Ceramics

    SciTech Connect

    Ray, Hannah L.; Jonghe, Lutgard C. De

    2010-06-02

    The total conductivity of Sr-doped cerium orthophosphate changes by nearly two orders of magnitude depending on the oxygen and hydrogen content of the atmosphere. The defect model for the system suggests that this is because the identity of the dominant charge carrier can change from electron holes to protons when the sample is in equilibrium with air vs. humidified hydrogen. In this work are presented some preliminary measurements that can help to clarify this exchange between carriers. The conduction behavior of a 2percent Sr-doped CePO4 sample under symmetric atmospheric conditions is investigated using several techniques, including AC impedance, H/D isotope effects, and chronoamperometry.

  3. Properties of hot liquid cerium by LDA + U molecular dynamics.

    PubMed

    Siberchicot, Bruno; Clérouin, Jean

    2012-11-14

    We present ab initio simulations of liquid cerium in the framework of the LDA + U formulation. The liquid density has been determined self-consistently by searching for the zero pressure equilibrium state at 1320 K with the same set of parameters (U and J) and occupation matrices as those optimized for the γ phase. We have computed static and transport properties. The liquid produced by the simulations appears more structured than the available measurements. This raises questions regarding the ability of the theory to describe such a complex liquid. Conductivity calculations and temperature dependences are nevertheless in reasonable agreement with data.

  4. Soil organic matter influences cerium translocation and physiological processes in kidney bean plants exposed to cerium oxide nanoparticles.

    PubMed

    Majumdar, Sanghamitra; Peralta-Videa, Jose R; Trujillo-Reyes, Jesica; Sun, Youping; Barrios, Ana C; Niu, Genhua; Margez, Juan P Flores-; Gardea-Torresdey, Jorge L

    2016-11-01

    Soil organic matter plays a major role in determining the fate of the engineered nanomaterials (ENMs) in the soil matrix and effects on the residing plants. In this study, kidney bean plants were grown in soils varying in organic matter content and amended with 0-500mg/kg cerium oxide nanoparticles (nano-CeO2) under greenhouse condition. After 52days of exposure, cerium accumulation in tissues, plant growth and physiological parameters including photosynthetic pigments (chlorophylls and carotenoids), net photosynthesis rate, transpiration rate, and stomatal conductance were recorded. Additionally, catalase and ascorbate peroxidase activities were measured to evaluate oxidative stress in the tissues. The translocation factor of cerium in the nano-CeO2 exposed plants grown in organic matter enriched soil (OMES) was twice as the plants grown in low organic matter soil (LOMS). Although the leaf cover area increased by 65-111% with increasing nano-CeO2 concentration in LOMS, the effect on the physiological processes were inconsequential. In OMES leaves, exposure to 62.5-250mg/kg nano-CeO2 led to an enhancement in the transpiration rate and stomatal conductance, but to a simultaneous decrease in carotenoid contents by 25-28%. Chlorophyll a in the OMES leaves also decreased by 27 and 18% on exposure to 125 and 250mg/kg nano-CeO2. In addition, catalase activity increased in LOMS stems, and ascorbate peroxidase increased in OMES leaves of nano-CeO2 exposed plants, with respect to control. Thus, this study provides clear evidence that the properties of the complex soil matrix play decisive roles in determining the fate, bioavailability, and biological transport of ENMs in the environment.

  5. Soil organic matter influences cerium translocation and physiological processes in kidney bean plants exposed to cerium oxide nanoparticles.

    PubMed

    Majumdar, Sanghamitra; Peralta-Videa, Jose R; Trujillo-Reyes, Jesica; Sun, Youping; Barrios, Ana C; Niu, Genhua; Margez, Juan P Flores-; Gardea-Torresdey, Jorge L

    2016-11-01

    Soil organic matter plays a major role in determining the fate of the engineered nanomaterials (ENMs) in the soil matrix and effects on the residing plants. In this study, kidney bean plants were grown in soils varying in organic matter content and amended with 0-500mg/kg cerium oxide nanoparticles (nano-CeO2) under greenhouse condition. After 52days of exposure, cerium accumulation in tissues, plant growth and physiological parameters including photosynthetic pigments (chlorophylls and carotenoids), net photosynthesis rate, transpiration rate, and stomatal conductance were recorded. Additionally, catalase and ascorbate peroxidase activities were measured to evaluate oxidative stress in the tissues. The translocation factor of cerium in the nano-CeO2 exposed plants grown in organic matter enriched soil (OMES) was twice as the plants grown in low organic matter soil (LOMS). Although the leaf cover area increased by 65-111% with increasing nano-CeO2 concentration in LOMS, the effect on the physiological processes were inconsequential. In OMES leaves, exposure to 62.5-250mg/kg nano-CeO2 led to an enhancement in the transpiration rate and stomatal conductance, but to a simultaneous decrease in carotenoid contents by 25-28%. Chlorophyll a in the OMES leaves also decreased by 27 and 18% on exposure to 125 and 250mg/kg nano-CeO2. In addition, catalase activity increased in LOMS stems, and ascorbate peroxidase increased in OMES leaves of nano-CeO2 exposed plants, with respect to control. Thus, this study provides clear evidence that the properties of the complex soil matrix play decisive roles in determining the fate, bioavailability, and biological transport of ENMs in the environment. PMID:27343939

  6. Hydrothermal synthesis of cerium titanate nanorods and its application in visible light photocatalysis

    SciTech Connect

    Pei, L.Z. Liu, H.D.; Lin, N.; Yu, H.Y.

    2015-01-15

    Highlights: • Cerium titanate nanorods have been synthesized by a simple hydrothermal process. • The size of the cerium titanate nanorods can be controlled by growth conditions. • Cerium titanate nanorods exhibit good photocatalytic activities for methyl blue. - Abstract: Cerium titanate nanorods have been prepared via a hydrothermal process using sodium dodecyl sulfate (SDS) as the surfactant. The cerium titanate nanorods have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and ultraviolet–visible (UV–vis) diffuse reflectance spectrum. XRD shows that the nanorods are composed of CeTi{sub 21}O{sub 38} phase. Electron microscopy observations indicate that the nanorods have good single crystalline nature. The diameter and length of the nanorods are about 50–200 nm and 1–2 μm, respectively. Cerium titanate nanorods have a band gap of 2.65 eV. The photocatalytic activities of the nanorods have been investigated by degrading methylene blue (MB) under visible light irradiation. MB solution with the concentration of 10 mg L{sup −1} can be degraded totally with the irradiation time increasing to 240 min. Cerium titanate nanorods exhibit great potential in photocatalytic degradation of MB under visible light irradiation.

  7. Altering properties of cerium oxide thin films by Rh doping

    SciTech Connect

    Ševčíková, Klára; Nehasil, Václav; Vorokhta, Mykhailo; Haviar, Stanislav; Matolín, Vladimír; and others

    2015-07-15

    Highlights: • Thin films of ceria doped by rhodium deposited by RF magnetron sputtering. • Concentration of rhodium has great impact on properties of Rh–CeO{sub x} thin films. • Intensive oxygen migration in films with low concentration of rhodium. • Oxygen migration suppressed in films with high amount of Rh dopants. - Abstract: Ceria containing highly dispersed ions of rhodium is a promising material for catalytic applications. The Rh–CeO{sub x} thin films with different concentrations of rhodium were deposited by RF magnetron sputtering and were studied by soft and hard X-ray photoelectron spectroscopies, Temperature programmed reaction and X-ray powder diffraction techniques. The sputtered films consist of rhodium–cerium mixed oxide where cerium exhibits a mixed valency of Ce{sup 4+} and Ce{sup 3+} and rhodium occurs in two oxidation states, Rh{sup 3+} and Rh{sup n+}. We show that the concentration of rhodium has a great influence on the chemical composition, structure and reducibility of the Rh–CeO{sub x} thin films. The films with low concentrations of rhodium are polycrystalline, while the films with higher amount of Rh dopants are amorphous. The morphology of the films strongly influences the mobility of oxygen in the material. Therefore, varying the concentration of rhodium in Rh–CeO{sub x} thin films leads to preparing materials with different properties.

  8. Pulmonary toxicity in mice following exposure to cerium chloride.

    PubMed

    Hong, Jie; Yu, Xiaohong; Pan, Xiaoyu; Zhao, Xiaoyang; Sheng, Lei; Sang, Xuezi; Lin, Anan; Zhang, Chi; Zhao, Yue; Gui, Suxin; Sun, Qingqing; Wang, Ling; Hong, Fashui

    2014-06-01

    The widespread application of lanthanoids (Lns) in manufacturing industries has raised occupational and environmental health concerns about the possible increased health risks to humans exposed to Lns in their working and living environments. Numerous studies have shown that exposures to Ln cause pulmonary injury in animals, but very little is known about the molecular mechanisms of the pulmonary inflammation caused by cerium chloride (CeCl3) exposure. In this study, we evaluated the oxidative stress and molecular mechanism underlying with the pulmonary inflammation associated with chronic lung toxicity in mice treated with nasally instilled CeCl3 for 90 consecutive days. Our findings suggest that significant cerium accumulated in the lung, leading the obvious increase of the lung indices, significant increases in inflammatory cells and levels of lactate dehydrogenase, alkaline phosphate, and total protein, overproduction of reactive oxygen species and peroxidation of lipids, reduced antioxidant capacity, and pulmonary inflammation. CeCl3 exposure also activated nuclear factor κB, increased the expression of tumor necrosis factor α, cyclooxygenase-2, heme oxygenase 1, interleukin 2, interleukin 4, interleukin 6, interleukin 8, interleukin 10, interleukin 18, interleukin 1β, and CYP1A1. However, CeCl3 reduced the expression of nuclear factor κB (NF-κB)-inhibiting factor and heat shock protein 70. These findings suggest that the pulmonary inflammation caused by CeCl3 in mice is closely associated with oxidative stress and inflammatory cytokine expression. PMID:24736977

  9. Serum ornithine carbamoyltransferase (OCT) in rats poisoned with lanthanum, cerium and praseodymium.

    PubMed

    Marciniak, M; Bałtrukiewicz, Z

    1977-01-01

    Serum ornithine carbamoyltransferase (OCT) in rats poisoned with lanthanum, cerium and praseodymium. Acta Physiol. Pol., 1977, 28 (6): 589-594. The serum ornithine carbamoyltransferase in relation to doses of lanthanum, cerium and praseodymium, administered intravenously as chlorides, was investigated. A directly proportional relationship was found between the doses of these compounds and the serum enzyme level in rats. The lowest doses at which a rise in the serum OCT level occured were determined. They were: lanthanum - 0.75 mg/kg of body weight, cerium - 1.5 mg/kg, and praseodymium - 3 mh/kg. A decreasing toxicity of these elements with increasing value of atomic number was observed.

  10. Cerium-Based Magnets: Novel High Energy Permanent Magnet Without Critical Elements

    SciTech Connect

    2012-01-01

    REACT Project: Ames Laboratory will develop a new class of permanent magnets based on the more commonly available element cerium for use in both EVs and renewable power generators. Cerium is 4 times more abundant and significantly less expensive than the rare earth element neodymium, which is frequently used in today’s most powerful magnets. Ames Laboratory will combine other metal elements with cerium to create a new magnet that can remain stable at the high temperatures typically found in electric motors. This new magnetic material will ultimately be demonstrated in a prototype electric motor, representing a cost-effective and efficient alternative to neodymium-based motors.

  11. Studies of Solution Deposited Cerium Oxide Thin Films on Textured Ni-Alloy Substractes for YBCO Superconductor

    SciTech Connect

    Stewart, Erin L; Bhuiyan, Md S; Sathyamurthy, Srivatsan; Paranthaman, Mariappan Parans

    2006-01-01

    Cerium oxide (CeO2) buffer layers play an important role for the development of YBa2Cu3O7-x (YBCO) based superconducting tapes using the rolling assisted biaxially textured substrates (RABiTS) approach. The chemical solution deposition (CSD) approach has been used to grow epitaxial CeO2 films on textured Ni-3 a 4% W alloy substrates with various starting precursors of ceria. Precursors such as cerium acetate, cerium acetylacetonate, cerium 2-ethylhexanoate, cerium nitrate, and cerium trifluoroacetate were prepared in suitable solvents. The optimum growth conditions for these cerium precursors were Ar-4% H2 gas processing atmosphere, solution concentration levels of 0.2-0.5 M, a dwell time of 15 min, and a process temperature range of 1050-1150 degrees C. X-ray diffraction, AFM, SEM, and optical microscopy were used to characterize the CeO2 films. Highly textured CeO2 layers were obtained on Ni-W substrates with both cerium acetate and cerium acetylacetonate as starting precursors. YBCO films with a Jc of 1.5 MA/cm2 were obtained on cerium acetylacetonate-based CeO2 films with sputtered YSZ and CeO2 cap layers.

  12. 14 CFR 139.341 - Identifying, marking, and lighting construction and other unserviceable areas.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Identifying, marking, and lighting construction and other unserviceable areas. 139.341 Section 139.341 Aeronautics and Space FEDERAL AVIATION...: CERTIFICATION AND OPERATIONS CERTIFICATION OF AIRPORTS Operations § 139.341 Identifying, marking, and...

  13. 14 CFR 139.341 - Identifying, marking, and lighting construction and other unserviceable areas.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Identifying, marking, and lighting construction and other unserviceable areas. 139.341 Section 139.341 Aeronautics and Space FEDERAL AVIATION...: CERTIFICATION AND OPERATIONS CERTIFICATION OF AIRPORTS Operations § 139.341 Identifying, marking, and...

  14. 14 CFR 139.341 - Identifying, marking, and lighting construction and other unserviceable areas.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Identifying, marking, and lighting construction and other unserviceable areas. 139.341 Section 139.341 Aeronautics and Space FEDERAL AVIATION...: CERTIFICATION AND OPERATIONS CERTIFICATION OF AIRPORTS Operations § 139.341 Identifying, marking, and...

  15. 14 CFR 139.341 - Identifying, marking, and lighting construction and other unserviceable areas.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Identifying, marking, and lighting construction and other unserviceable areas. 139.341 Section 139.341 Aeronautics and Space FEDERAL AVIATION...: CERTIFICATION AND OPERATIONS CERTIFICATION OF AIRPORTS Operations § 139.341 Identifying, marking, and...

  16. 14 CFR 139.341 - Identifying, marking, and lighting construction and other unserviceable areas.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Identifying, marking, and lighting construction and other unserviceable areas. 139.341 Section 139.341 Aeronautics and Space FEDERAL AVIATION...: CERTIFICATION AND OPERATIONS CERTIFICATION OF AIRPORTS Operations § 139.341 Identifying, marking, and...

  17. 47 CFR 13.9 - Eligibility and application for new license or endorsement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Eligibility and application for new license or endorsement. 13.9 Section 13.9 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL RADIO OPERATORS General § 13.9 Eligibility and application for new license or endorsement. (a) If found...

  18. 15 CFR 13.9 - Receipt of and response to comments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Receipt of and response to comments. 13.9 Section 13.9 Commerce and Foreign Trade Office of the Secretary of Commerce INTERGOVERNMENTAL REVIEW OF DEPARTMENT OF COMMERCE PROGRAMS AND ACTIVITIES § 13.9 Receipt of and response to comments....

  19. 10 CFR 26.139 - Reporting initial validity and drug test results.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility...

  20. 10 CFR 26.139 - Reporting initial validity and drug test results.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility...

  1. Correction: Single-molecule magnet behaviour in polynuclear assembly of trivalent cerium ions with polyoxomolybdates.

    PubMed

    Khélifa, A Ben; Belkhiria, M Salah; Huang, G; Freslon, S; Guillou, O; Bernot, K

    2016-06-01

    Correction for 'Single-molecule magnet behaviour in polynuclear assembly of trivalent cerium ions with polyoxomolybdates' by A. Ben Khélifa, et al., Dalton Trans., 2015, 44, 16458-16464. PMID:27161299

  2. Calculation of a volume effect accompanying an electronic topological transition in pure cerium

    NASA Astrophysics Data System (ADS)

    Ponomaryova, S. O.; Koval', Yu. M.; Ponomaryov, O. P.

    2012-10-01

    An analytic expression for estimating the volume effect accompanying an electronic topological transition (ETT) in pure cerium is derived on the basis of the microscopic Falikov-Ramirez-Kimball model.

  3. Recent advances (2010-2015) in studies of cerium oxide nanoparticles' health effects.

    PubMed

    Li, Yan; Li, Peng; Yu, Hua; Bian, Ying

    2016-06-01

    Cerium oxide nanoparticles, widespread applied in our life, have attracted much concern for their human health effects. However, most of the works addressing cerium oxide nanoparticles toxicity have only used in vitro models or in vivo intratracheal instillation methods. The toxicity studies have varied results and not all are conclusive. The information about risk assessments derived from epidemiology studies is severely lacking. The knowledge of occupational safety and health (OSH) for exposed workers is very little. Thus this review focuses on recent advances in studies of toxicokinetics, antioxidant activity and toxicity. Additionally, aim to extend previous health effects assessments of cerium oxide nanoparticles, we summarize the epidemiology studies of engineered cerium oxide nanoparticles used as automotive diesel fuel additive, aerosol particulate matter in air pollution, other industrial ultrafine and nanoparticles (e.g., fumes particles generated in welding and flame cutting processes). PMID:27088851

  4. Direct growth of cerium oxide nanorods on diverse substrates for superhydrophobicity and corrosion resistance

    NASA Astrophysics Data System (ADS)

    Cho, Young Jun; Jang, Hanmin; Lee, Kwan-Soo; Kim, Dong Rip

    2015-06-01

    Superhydrophobic surfaces with anti-corrosion properties have attracted great interest in many industrial fields, particularly to enhance the thermal performance of offshore applications such as heat exchangers, pipelines, power plants, and platform structures. Nanostructures with hydrophobic materials have been widely utilized to realize superhydrophobicity of surfaces, and cerium oxide has been highlighted due to its good corrosion resistive and intrinsically hydrophobic properties. However, few studies of direct growth of cerium oxide nanostructures on diverse substrates have been reported. Herein we report a facile hydrothermal method to directly grow cerium oxide nanorods on diverse substrates, such as aluminum alloy, stainless steel, titanium, and silicon. Diverse substrates with cerium oxide nanorods exhibited superhydrophobicity with no hydrophobic modifiers on their surfaces, and showed good corrosion resistive properties in corrosive medium. We believe our method could pave the way for realization of scalable and sustainable corrosion resistive superhydrophobic surfaces in many industrial fields.

  5. Inhaled Diesel Emissions Generated with Cerium Oxide Nanoparticle Fuel Additive Induce Adverse Pulmonary and Systemic Effects

    EPA Science Inventory

    Diesel exhaust (DE) exposure induces adverse cardiopulmonary effects. Cerium oxide nanoparticles added to diesel fuel (DECe) increases fuel burning efficiency but leads to altered emission characteristics and potentially altered health effects. Here, we evaluated whether DECe res...

  6. Antioxidant properties of cerium oxide nanocrystals as a function of nanocrystal diameter and surface coating.

    PubMed

    Lee, Seung Soo; Song, Wensi; Cho, Minjung; Puppala, Hema L; Nguyen, Phuc; Zhu, Huiguang; Segatori, Laura; Colvin, Vicki L

    2013-11-26

    This work examines the effect of nanocrystal diameter and surface coating on the reactivity of cerium oxide nanocrystals with H2O2 both in chemical solutions and in cells. Monodisperse nanocrystals were formed in organic solvents from the decomposition of cerium precursors, and subsequently phase transferred into water using amphiphiles as nanoparticle coatings. Quantitative analysis of the antioxidant capacity of CeO2-x using gas chromatography and a luminol test revealed that 2 mol of H2O2 reacted with every mole of cerium(III), suggesting that the reaction proceeds via a Fenton-type mechanism. Smaller diameter nanocrystals containing more cerium(III) were found to be more reactive toward H2O2. Additionally, the presence of a surface coating did not preclude the reaction between the nanocrystal surface cerium(III) and hydrogen peroxide. Taken together, the most reactive nanoparticles were the smallest (e.g., 3.8 nm diameter) with the thinnest surface coating (e.g., oleic acid). Moreover, a benchmark test of their antioxidant capacity revealed these materials were 9 times more reactive than commercial antioxidants such as Trolox. A unique feature of these antioxidant nanocrystals is that they can be applied multiple times: over weeks, cerium(IV) rich particles slowly return to their starting cerium(III) content. In nearly all cases, the particles remain colloidally stable (e.g., nonaggregated) and could be applied multiple times as antioxidants. These chemical properties were also observed in cell culture, where the materials were able to reduce oxidative stress in human dermal fibroblasts exposed to H2O2 with efficiency comparable to their solution phase reactivity. These data suggest that organic coatings on cerium oxide nanocrystals do not limit the antioxidant behavior of the nanocrystals, and that their redox cycling behavior can be preserved even when stabilized. PMID:24079896

  7. Static and dynamic high pressure experiments on cerium

    SciTech Connect

    Jensen, Brian J; Velisavljevic, Nenad; Cherne, Frank J; Stevens, Gerald; Tschauner, Oliver

    2011-01-25

    There is a scientific need to obtain dynamic data to develop and validate multi phase equation-of-state (EOS) models for metals. Experiments are needed to examine the relevant pure phases, to locate phase boundaries and the associated transition kinetics, and other material properties such as strength. Cerium is an ideal material for such work because it exhibits a complex multiphase diagram at relatively moderate pressures readily accessible using standard shock wave methods. In the current work, shock wave (dynamic) and diamond anvil cell (static) experiments were performed to examine the high pressure, low temperature region of the phase diagram to obtain EOS data and to search for the {alpha}-{var_epsilon} boundary. Past work examining the shock-melt transition and the low-pressure {gamma}-{alpha} transition will be presented in brief followed by details of recent results obtained from DAC and double-shock experiments.

  8. The Spin Glass-Kondo Competition in Disordered Cerium Systems

    NASA Astrophysics Data System (ADS)

    Magalhaes, S. G.; Zimmer, F.; Coqblin, B.

    2013-10-01

    We discuss the competition between the Kondo effect, the spin glass state and a magnetic order observed in disordered Cerium systems. We present firstly the experimental situation of disordered alloys such as CeNi1 - xCux and then the different theoretical approaches based on the Kondo lattice model, with different descriptions of the intersite exchange interaction for the spin glass. After the gaussian approach of the Sherrington-Kirkpatrick model, we discuss the Mattis and the van Hemmen models. Then, we present simple cluster calculations in order to describe the percolative evolution of the clusters from the cluster spin glass to the inhomogeneous ferromagnetic order recently observed in CeNi1 - xCux disordered alloys and finally we discuss the effect of random and transverse magnetic field.

  9. Growth of transition metals on cerium tungstate model catalyst layers

    NASA Astrophysics Data System (ADS)

    Skála, T.; Tsud, N.; Stetsovych, V.; Mysliveček, J.; Matolín, V.

    2016-10-01

    Two model catalytic metal/oxide systems were investigated by photoelectron spectroscopy and scanning tunneling microscopy. The mixed-oxide support was a cerium tungstate epitaxial thin layer grown in situ on the W(1 1 0) single crystal. Active particles consisted of palladium and platinum 3D islands deposited on the tungstate surface at 300 K. Both metals were found to interact weakly with the oxide support and the original chemical state of both support and metals was mostly preserved. Electronic and morphological changes are discussed during the metal growth and after post-annealing at temperatures up to 700 K. Partial transition-metal coalescence and self-cleaning from the CO and carbon impurities were observed.

  10. Characterization of a zinc-cerium flow battery

    NASA Astrophysics Data System (ADS)

    Leung, P. K.; Ponce-de-León, C.; Low, C. T. J.; Shah, A. A.; Walsh, F. C.

    The performance of a divided, parallel-plate zinc-cerium redox flow battery using methanesulfonic acid electrolytes was studied. Eight two and three-dimensional electrodes were tested under both constant current density and constant cell voltage discharge. Carbon felt and the three-dimensional platinised titanium mesh electrodes exhibited superior performance over the 2-dimensional electrodes. The charge and discharge characteristics of the redox flow battery were studied under different operating conditions and Zn/Ce reactant, as well as methansulfonic acid concentration. The cell performance improved at higher operating temperatures and faster electrolyte flow velocities. The number of possible cycles increased at reduced states of charge. During 15 min charge/discharge per cycle experiment, 57 cycles were obtained and the zinc reaction was found to be the limiting process during long term operation.

  11. Redox reactivity of cerium oxide nanoparticles against dopamine.

    PubMed

    Hayat, Akhtar; Andreescu, Daniel; Bulbul, Gonca; Andreescu, Silvana

    2014-03-15

    The interaction between dopamine and the redox active cerium oxide nanoparticles, or nanoceria was studied using a suite of spectroscopic and surface characterization methods. Changes in the chemical reactivity and concentration of dopamine upon exposure to nanoceria was assessed in aqueous solutions and a human physiological fluid--human serum. The results indicate strong attachment of dopamine to the nanoparticle surface through oxidation followed by chemisorption of the oxidative product with formation of a charge transfer complex. Such oxidation/surface adsorption processes between nanoceria and dopamine lead to a reduction of the concentration of free dopamine in aqueous environments. These findings suggest that the redox reactivity of nanoceria may alter dopamine levels in biological systems exposed to these particles and indicate the need for a comprehensive assessment of the potential neurological consequences that might result from intended or unintended exposure to these particles. PMID:24461841

  12. Growth of transition metals on cerium tungstate model catalyst layers.

    PubMed

    Skála, T; Tsud, N; Stetsovych, V; Mysliveček, J; Matolín, V

    2016-10-01

    Two model catalytic metal/oxide systems were investigated by photoelectron spectroscopy and scanning tunneling microscopy. The mixed-oxide support was a cerium tungstate epitaxial thin layer grown in situ on the W(1 1 0) single crystal. Active particles consisted of palladium and platinum 3D islands deposited on the tungstate surface at 300 K. Both metals were found to interact weakly with the oxide support and the original chemical state of both support and metals was mostly preserved. Electronic and morphological changes are discussed during the metal growth and after post-annealing at temperatures up to 700 K. Partial transition-metal coalescence and self-cleaning from the CO and carbon impurities were observed. PMID:27494195

  13. An Alkali Metal-Capped Cerium(IV) Imido Complex.

    PubMed

    Solola, Lukman A; Zabula, Alexander V; Dorfner, Walter L; Manor, Brian C; Carroll, Patrick J; Schelter, Eric J

    2016-06-01

    Structurally authenticated, terminal lanthanide-ligand multiple bonds are rare and expected to be highly reactive. Even capped with an alkali metal cation, poor orbital energy matching and overlap of metal and ligand valence orbitals should result in strong charge polarization within such bonds. We expand on a new strategy for isolating terminal lanthanide-ligand multiple bonds using cerium(IV) complexes. In the current case, our tailored tris(hydroxylaminato) ligand framework, TriNOx(3-), provides steric protection against ligand scrambling and metal complex oligomerization and electronic protection against reduction. This strategy culminates in isolation of the first formal Ce═N bonded moiety in the complex [K(DME)2][Ce═N(3,5-(CF3)2C6H3)(TriNOx)], whose Ce═N bond is the shortest known at 2.119(3) Å. PMID:27163651

  14. Role of nanocrystalline cerium oxide coatings on austenitic stainless steels

    NASA Astrophysics Data System (ADS)

    Zhang, Haiying

    Protective nanocrystalline cerium oxide coating has been applied to ASTM grade 304L and 304 austenitic stainless steels to improve its oxidation resistance at elevated temperatures. Experimentally, the selected alloy was exposed to 800°C/1000°C under dry air conditions. Weight changes (DeltaW/A) were monitored as a function of time and the results were compared with uncoated alloys tested under similar conditions. It was found that the oxidation resistances of 304L and 304 stainless steels were significantly improved. A comparison of the oxidation rates indicated that the nanocrystalline cerium oxide coating reduced the rate of oxidation by more than two orders of magnitude. Nevertheless, a comprehensive understanding of the mechanisms responsible for the reduction in the oxidation rate is not clear. Consequently, this work is aimed at investigating the mechanisms involved during scale growth in the presence or absence of nanocrystalline coatings. For this purpose, density functional theory was carried out in order to predict oxygen and iron diffusion microscopic activation energies and reveal the intrinsic characteristics of nanocrystalline coatings. A numerical simulation of corrosion process has also been conducted to predict the corrosion rates of alloys with and without coatings. Hence, the results from simulations are compared with the experimental outcome, and possible explanations are given to account for the reduction in the exhibited oxidation rates. The simulation results will provide a highly valuable tool for the realization of functional nanostructures and architectures "by design", particularly in the development of novel coatings, and a new approach of life assessment.

  15. Induction of pulmonary fibrosis by cerium oxide nanoparticles

    PubMed Central

    Ma, Jane Y.; Mercer, Robert R.; Barger, Mark; Schwegler-Berry, Diane; Scabilloni, James; Ma, Joseph K.; Castranova, Vincent

    2015-01-01

    Cerium compounds have been used as a diesel engine catalyst to lower the mass of diesel exhaust particles, but are emitted as cerium oxide (CeO2) nanoparticles in the diesel exhaust. In a previous study, we have demonstrated a wide range of CeO2-induced lung responses including sustained pulmonary inflammation and cellular signaling that could lead to pulmonary fibrosis. In this study, we investigated the fibrogenic responses induced by CeO2 in a rat model at various time points up to 84 days post-exposure. Male Sprague Dawley rats were exposed to CeO2 by a single intratracheal instillation. Alveolar macrophages (AM) were isolated by bronchial alveolar lavage (BAL). AM-mediated cellular responses, osteopontin (OPN) and transform growth factor (TGF)-β1 in the fibrotic process were investigated. The results showed that CeO2 exposure significantly increased fibrotic cytokine TGF-β1 and OPN production by AM above controls. The collagen degradation enzymes, matrix metalloproteinase (MMP)-2 and -9 and the tissue inhibitor of MMP were markedly increased in the BAL fluid at 1 day- and subsequently declined at 28 days after exposure, but remained much higher than the controls. CeO2 induced elevated phospholipids in BAL fluid and increased hydroxyproline content in lung tissue in a dose- and time-dependent manner. Immunohistochemical analysis showed MMP-2, MMP-9 and MMP-10 expressions in fibrotic regions. Morphological analysis noted increased collagen fibers in the lungs exposed to a single dose of 3.5 mg/kg CeO2 and euthanized at 28 days post-exposure. Collectively, our studies show that CeO2 induced fibrotic lung injury in rats, suggesting it may cause potential health effects. PMID:22613087

  16. Synthesis and catalytic properties of microemulsion-derived cerium oxide nanoparticles

    SciTech Connect

    Kockrick, Emanuel; Schrage, Christian; Grigas, Anett; Geiger, Dorin; Kaskel, Stefan

    2008-07-15

    The synthesis of cerium dioxide nanoparticles using an inverse microemulsion technique and precipitation method was investigated. Cerium hydroxide nanoparticles were synthesized by adding diluted ammonia to n-heptane-surfactant-cerium nitrate system. The micelle and particle size in the range of 5-12 nm were controlled by varying the molar water to surfactant ratio and analyzed by dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and high-resolution transmission electron microscopy (HRTEM). Cerium hydroxide nanoparticles were isolated and subsequently treated at 100-600 deg. C to obtain nanoscale ceria. Crystallite sizes of cerium dioxide in the range of 6-16 nm were estimated by Scherrer analysis by X-ray diffraction (XRD) and HRTEM. The catalytic activity of particles annealed at 400 and 600 deg. C in soot combustion reactions was characterized by temperature-programmed oxidation (TPO) indicating a size-dependant activity. Crystallite sizes and catalytic stability of elevated ceria systems were tested in second combustion cycles. - Graphical abstract: The synthesis of cerium dioxide nanoparticles using an inverse microemulsion technique and precipitation method was investigated using small angle X-ray scattering, dynamic light scattering and high-resolution transmission electron microscopy. Catalytic activity of ceria nanoparticles was tested in soot combustion reaction indicating size-dependent reactivity.

  17. The results of radiosurgical management of 139 single cerebral metastases.

    PubMed

    Valentino, V

    1995-01-01

    Between March 1984 and June 1993, linac radiosurgery was performed in 139 patients for single brain metastases, using the non-invasive (Greitz-Bergström) head fixation system. This atraumatic system was utilized for subsequent stereotactic CT/NMR staging to obtain strictly comparable neuro-imaging. Thus, tumour response was evaluated precisely and radiosurgery repeated (straight after the diagnostic sitting), as needed. No hospitalization or anaesthesia was necessary. The 25 mm target was the maximum size to avoid the risk of radiation induced reactions. In metastases exceeding this limit single doses were directed at more than one target at the same session. Focusing upon single or multiple targets was facilitated by 3-D stereotactic NMR. The results after one single sitting were compared with those obtained after staged sittings in the same patients. Radiosurgery achieved disappearance or shrinkage of the metastasis with resolution of the oedema and mid-line shift in 86% of the 139 patients treated. In 47% of them, however, the success was the result of repeat radiosurgery and staged sittings. The non-invasive procedure is the keystone to optimize the radiosurgical results.

  18. Sirius Rising 139 AD: Hadrian, Tivoli, and the Tazza Farnese

    NASA Astrophysics Data System (ADS)

    Aakhus, P. L.

    2011-06-01

    The heliacal rising of Sirius in 139 AD, intersecting with the beginning of the Egyptian year after an interval of 1461 years, signaled abundant fertility derived from the flooding of the Nile and the resurrection of Osiris. Hadrian's preparation for this event, which he did not live to see, at his villa in Tivoli was concurrent with the establishment of the cult of Antinoos assimilated to Osiris, Hermes and Master of the Hounds, following his drowning in the Nile. The site of the obelisk marking Antinoos' tomb and describing his resurrection has recently been discovered near the so-called "Canopus" at Tivoli , where the prominent placement of Demeter/Isis/Sothis and Antinoos/Osiris suggests the rising of Sirius on 20 July 139 AD and flooding of the Nile. Furthermore, this astronomical-cultural event shown on coins and gems of the period, may also be represented in the much debated iconography of the Tazza Farnese, a carved Hellenistic sardonyx libation bowl owned by a prince of Samarkand, Lorenzo de' Medici, and Frederick II, and said to have been found in Hadrian's tomb.

  19. Measurement of 139La(n,γ) Cross Section

    NASA Astrophysics Data System (ADS)

    Terlizzi, R.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fujii, K.; Furman, W.; Gallino, R.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karamanis, D.; Karadimos, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Mastinu, P.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2006-03-01

    We measured the neutron capture cross section of 139La relative to 197Au in the energy range of 0.6 eV to 9 keV at n_TOF, the neutron time-of-flight facility at CERN. After a description of the experimental apparatus, we discuss data analysis procedures. The data were fitted using R-matrix formalism to extract resonance parameters which, in turn, were used to calculate average level spacings D0 = 268 ± 22 eV and D1 < 250 eV, and neutron strength functions S0 = (0.79 ± 0.03)×10-4 and S1 = (0.73 ± 0.05)×10-4 for s- and p-wave resonances. The data also were used to determine Maxwellian-averaged neutron capture cross sections which, in turn, were used to calculate the 139La abundance synthesized in a stellar model of the main component of the s process.

  20. Copper, Boron, and Cerium Additions in Type 347 Austenitic Steel to Improve Creep Rupture Strength

    NASA Astrophysics Data System (ADS)

    Laha, Kinkar; Kyono, J.; Shinya, Norio

    2012-04-01

    Type 347 austenitic stainless steel (18Cr-12Ni-Nb) was alloyed with copper (3 wt pct), boron (0.01 to 0.06 wt pct), and cerium (0.01 wt pct) with an aim to increase the creep rupture strength of the steel through the improved deformation and cavitation resistance. Short-term creep rupture strength was found to increase with the addition of copper in the 347 steel, but the long-term strength was inferior. Extensive creep cavitation deprived the steel of the beneficial effect of creep deformation resistance induced by nano-size copper particles. Boron and cerium additions in the copper-containing steel increased its creep rupture strength and ductility, which were more for higher boron content. Creep deformation, grain boundary sliding, and creep cavity nucleation and growth in the steel were found to be suppressed by microalloying the copper-containing steel with boron and cerium, and the suppression was more for higher boron content. An auger electron spectroscopic study revealed the segregation of boron instead of sulfur on the cavity surface of the boron- and cerium-microalloyed steel. Cerium acted as a scavenger for soluble sulfur in the steels through the precipitation of cerium sulfide (CeS). This inhibited the segregation of sulfur and facilitated the segregation of boron on cavity surface. Boron segregation on the nucleated cavity surface reduced its growth rate. Microalloying the copper-containing 347 steel with boron and cerium thus enabled to use the full extent of creep deformation resistance rendered by copper nano-size particle by increase in creep rupture strength and ductility.

  1. Exposure and Health Effects Review of Engineered Nanoscale Cerium and Cerium Dioxide Associated with its Use as a Fuel Additive - NOW IN PRINT IN THE JOURNAL

    EPA Science Inventory

    Advances of nanoscale science have produced nanomaterials with unique physical and chemical properties at commercial levels that are now incorporated into over 1000 products. Nanoscale cerium (di) oxide (Ce02) has recently gained a wide range of applications which includes coatin...

  2. Exposure, Health and Ecological Effects Review of Engineered Nanoscale Cerium and Cerium Oxide Associated with its Use as a Fuel Additive

    EPA Science Inventory

    Advances of nanoscale science have produced nanomaterials with unique physical and chemical properties at commercial levels which are now incorporated into over 1000 products. Nanoscale cerium (di) oxide (CeO(2)) has recently gained a wide range of applications which includes coa...

  3. Thermochemical Modeling of the Uranium-Cerium-Oxygen System

    SciTech Connect

    Voit, Stewart L; Besmann, Theodore M

    2010-10-01

    with actinide materials, fundamental studies with uranium are performed using surrogate materials as stand-ins for transuranic elements. In most cases, cerium can be used as a suitable substitute for plutonium when performing O:M and sintering kinetics studies because of identical valence states. Differences exist between the magnitude of reported thermodynamic data of (U,Pu)O{sub x} and (U,Ce)O{sub x}, however the change in oxygen potential versus O:M follows the same trend for both systems. Cerium is also a major fission product element, and thus understanding its behavior in fuel is an important issue as well.

  4. Coupled redox transformations of catechol and cerium at the surface of a cerium(III) phosphate mineral

    NASA Astrophysics Data System (ADS)

    Cervini-Silva, Javiera; Gilbert, Benjamin; Fakra, Sirine; Friedlich, Stephan; Banfield, Jillian

    2008-05-01

    Highly insoluble Ce-bearing phosphate minerals form by weathering of apatite [Ca5(PO4)3.(OH,F,Cl)], and are important phosphorous repositories in soils. Although these phases can be dissolved via biologically-mediated pathways, the dissolution mechanisms are poorly understood. In this paper we report spectroscopic evidence to support coupling of redox transformations of organic carbon and cerium during the reaction of rhabdophane (CePO4·H2O) and catechol, a ubiquitous biogenic compound, at pH 5. Results show that the oxic-anoxic conditions influence the mineral dissolution behavior. Under anoxic conditions, the release of P and Ce occurs stoichiometrically. In contrast, under oxic conditions, the mineral dissolution behavior is incongruent, with dissolving Ce3+ ions oxidizing to CeO2. Reaction product analysis shows the formation of CO2, polymeric C, and oxalate and malate. The presence of more complex forms of organic carbon was also confirmed. Near edge X-ray absorption fine structure spectroscopy measurements at Ce-M4,5 and C-K absorption edges on reacted CePO4·H2O samples in the absence or presence of catechol and dissolved oxygen confirm that (1) the mineral surface converts to the oxide during this reaction, while full oxidation is limited to the near-surface region only; (2) the Ce valence remains unchanged when the reaction between CePO4·H2O and O2 but in the absence of catechol. Carbon K-edge spectra acquired from rhabdophane reacted with catechol under oxic conditions show spectral features before and after reaction that are considerably different from catechol, indicating the formation of more complex organic molecules. Decreases in intensity of characteristic catechol peaks are accompanied by the appearance of new π∗ resonances due to carbon in carboxyl (ca. 288.5 eV) and carbonyl (ca. 289.3 eV) groups, and the development of broad structure in the σ∗ region characteristic of aliphatic carbon. Evolution of the C K-edge spectra is consistent

  5. The nephronophthisis-related gene ift-139 is required for ciliogenesis in Caenorhabditis elegans

    PubMed Central

    Niwa, Shinsuke

    2016-01-01

    Defects in cilia cause a spectrum of diseases known as ciliopathies. Nephronophthisis, a ciliopathy, is the most common genetic cause of renal disease. Here, I cloned and analysed a nephronophthisis-related gene ift-139 in Caenorhabditis elegans. ift-139 was exclusively expressed in ciliated neurons in C. elegans. Genetic and cellular analyses suggest that ift-139 plays a role in retrograde intraflagellar transport and is required for cilia formation. A homologous point mutation that causes ciliopathy disrupted the function of ift-139 in C. elegans. ift-139 is an orthologue of human TTC21B, mutations in which are known to cause nephronophthisis 12 and short-rib thoracic dysplasia 4. These results suggest that ift-139 is evolutionarily conserved and fundamental to the formation of cilia. PMID:27515926

  6. A new class of homogeneous visible-light photocatalysts: molecular cerium vanadium oxide clusters.

    PubMed

    Seliverstov, Andrey; Streb, Carsten

    2014-07-28

    The first systematic access to molecular cerium vanadium oxides is presented. A family of structurally related, di-cerium-functionalized vanadium oxide clusters and their use as visible-light-driven photooxidation catalysts is reported. Comparative analyses show that photocatalytic activity is controlled by the cluster architecture. Increased photoreactivity of the cerium vanadium oxides in the visible range compared with nonfunctionalized vanadates is observed. Based on the recent discovery of the first molecular cerium vanadate cluster, (nBu4 N)2 [(Ce(dmso)3 )2 V12 O33 Cl]⋅2 DMSO (1), two new di-cerium-containing vanadium oxide clusters [(Ce(dmso)4 )2 V11 O30 Cl]⋅DMSO (2) and [(Ce(nmp)4 )2 V12 O32 Cl]⋅NMP⋅Me2 CO (3; NMP=N-methyl-2-pyrrolidone) were obtained by using a novel fragmentation and reassembly route. Pentagonal building units {(V)M5 } (M=V, Ce) reminiscent of "Müller-type" pentagons are observed in 2 and 3. Compounds 1-3 feature high visible-light photooxidative activity, and quantum efficiencies >10 % for indigo photooxidation are observed. Photocatalytic performance increases in the order 1<3<2. Mechanistic studies show that the irradiation wavelength and the presence of oxygen strongly affect photoreactivity. Initial findings suggest that the photooxidation mechanism proceeds by intermediate formation of hydroxyl radicals. The findings open new avenues for the bottom-up design of sunlight-driven photocatalysts.

  7. Exposure of cerium oxide nanoparticles to kidney bean shows disturbance in the plant defense mechanisms.

    PubMed

    Majumdar, Sanghamitra; Peralta-Videa, Jose R; Bandyopadhyay, Susmita; Castillo-Michel, Hiram; Hernandez-Viezcas, Jose-Angel; Sahi, Shivendra; Gardea-Torresdey, Jorge L

    2014-08-15

    Overwhelming use of engineered nanoparticles demands rapid assessment of their environmental impacts. The transport of cerium oxide nanoparticles (nCeO2) in plants and their impact on cellular homeostasis as a function of exposure duration is not well understood. In this study, kidney bean plants were exposed to suspensions of ∼ 8 ± 1 nm nCeO2 (62.5 to 500 mg/L) for 15 days in hydroponic conditions. Plant parts were analyzed for cerium accumulation after one, seven, and 15 days of nCeO2 exposure. The primary indicators of stress like lipid peroxidation, antioxidant enzyme activities, total soluble protein and chlorophyll contents were studied. Cerium in tissues was localized using scanning electron microscopy and synchrotron μ-XRF mapping, and the chemical forms were identified using μ-XANES. In the root epidermis, cerium was primarily shown to exist as nCeO2, although a small fraction (12%) was biotransformed to Ce(III) compound. Cerium was found to reach the root vascular tissues and translocate to aerial parts with time. Upon prolonged exposure to 500 mg nCeO2/L, the root antioxidant enzyme activities were significantly reduced, simultaneously increasing the root soluble protein by 204%. In addition, leaf's guaiacol peroxidase activity was enhanced with nCeO2 exposure in order to maintain cellular homeostasis. PMID:24981679

  8. Catalysts with Cerium in a Membrane Reactor for the Removal of Formaldehyde Pollutant from Water Effluents.

    PubMed

    Gutiérrez-Arzaluz, Mirella; Noreña-Franco, Luis; Ángel-Cuevas, Saúl; Mugica-Álvarez, Violeta; Torres-Rodríguez, Miguel

    2016-01-01

    We report the synthesis of cerium oxide, cobalt oxide, mixed cerium, and cobalt oxides and a Ce-Co/Al₂O₃ membrane, which are employed as catalysts for the catalytic wet oxidation (CWO) reaction process and the removal of formaldehyde from industrial effluents. Formaldehyde is present in numerous waste streams from the chemical industry in a concentration low enough to make its recovery not economically justified but high enough to create an environmental hazard. Common biological degradation methods do not work for formaldehyde, a highly toxic but refractory, low biodegradability substance. The CWO reaction is a recent, promising alternative that also permits much lower temperature and pressure conditions than other oxidation processes, resulting in economic benefits. The CWO reaction employing Ce- and Co-containing catalysts was carried out inside a slurry batch reactor and a membrane reactor. Experimental results are reported. Next, a mixed Ce-Co oxide film was supported on an γ-alumina membrane used in a catalytic membrane reactor to compare formaldehyde removal between both types of systems. Catalytic materials with cerium and with a relatively large amount of cerium favored the transformation of formaldehyde. Cerium was present as cerianite in the catalytic materials, as indicated by X-ray diffraction patterns. PMID:27231888

  9. Precipitation-Redispersion of Cerium Oxide Nanoparticles with Poly(acrylic acid): Toward Stable Dispersions

    SciTech Connect

    Sehgal,A.; Lalatonne, Y.; Berret, J.; Morvan, M.

    2005-01-01

    We exploit a precipitation-redispersion mechanism for complexation of short chain polyelectrolytes with cerium oxide nanoparticles to extend their stability ranges. As synthesized, cerium oxide sols at pH 1.4 consist of monodisperse cationic nanocrystalline particles having a hydrodynamic diameter of 10 nm and a molecular weight of 400 000 g mol{sup -1}. We show that short chain uncharged poly(acrylic acid) at low pH when added to a cerium oxide sols leads to macroscopic precipitation. As the pH is increased, the solution spontaneously redisperses into a clear solution of single particles with an anionic poly(acrylic acid) corona. The structure and dynamics of cerium oxide nanosols and their hybrid polymer-inorganic complexes in solution are investigated by static and dynamic light scattering, X-ray scattering, and chemical analysis. Quantitative analysis of the redispersed sol gives rise to an estimate of 40-50 polymer chains per particle for stable suspension. This amount represents 20% of the mass of the polymer-nanoparticle complexes. This complexation adds utility to the otherwise unstable cerium oxide dispersions by extending the range of stability of the sols in terms of pH, ionic strength, and concentration.

  10. Antioxidant Cerium Oxide Nanoparticles in Biology and Medicine

    PubMed Central

    Nelson, Bryant C.; Johnson, Monique E.; Walker, Marlon L.; Riley, Kathryn R.; Sims, Christopher M.

    2016-01-01

    Previously, catalytic cerium oxide nanoparticles (CNPs, nanoceria, CeO2-x NPs) have been widely utilized for chemical mechanical planarization in the semiconductor industry and for reducing harmful emissions and improving fuel combustion efficiency in the automobile industry. Researchers are now harnessing the catalytic repertoire of CNPs to develop potential new treatment modalities for both oxidative- and nitrosative-stress induced disorders and diseases. In order to reach the point where our experimental understanding of the antioxidant activity of CNPs can be translated into useful therapeutics in the clinic, it is necessary to evaluate the most current evidence that supports CNP antioxidant activity in biological systems. Accordingly, the aims of this review are three-fold: (1) To describe the putative reaction mechanisms and physicochemical surface properties that enable CNPs to both scavenge reactive oxygen species (ROS) and to act as antioxidant enzyme-like mimetics in solution; (2) To provide an overview, with commentary, regarding the most robust design and synthesis pathways for preparing CNPs with catalytic antioxidant activity; (3) To provide the reader with the most up-to-date in vitro and in vivo experimental evidence supporting the ROS-scavenging potential of CNPs in biology and medicine. PMID:27196936

  11. Deposition and investigation of lanthanum-cerium hexaboride thin films

    SciTech Connect

    Kuzanyan, A.S. . E-mail: akuzan@ipr.sci.am; Harutyunyan, S.R.; Vardanyan, V.O.; Badalyan, G.R.; Petrosyan, V.A.; Kuzanyan, V.S.; Petrosyan, S.I.; Karapetyan, V.E.; Wood, K.S.; Wu, H.-D.

    2006-09-15

    Thin films of lanthanum-cerium hexaboride, the promising thermoelectric material for low-temperature applications, are deposited on various substrates by the electron-beam evaporation, pulsed laser deposition and magnetron sputtering. The influence of the deposition conditions on the films X-ray characteristics, composition, microstructure and physical properties, such as the resistivity and Seebeck coefficient, is studied. The preferred (100) orientation of all films is obtained from XRD traces. In the range of 780-800 deg. C deposition temperature the highest intensity of diffractions peaks and the highest degree of the preferred orientation are observed. The temperature dependence of the resistivity and the Seebeck coefficient of films are investigated in the temperature range of 4-300 K. The features appropriate to Kondo effect in the dependences {rho}(T) and S(T) are detected at temperatures below 20 K. Interplay between the value of the Seebeck coefficient, metallic parameters and Kondo scattering of investigated films is discussed. - Graphical abstract: Kondo scattering in (La,Ce)B{sub 6} films: temperature dependence of the resistivity of (La,Ce)B{sub 6} films on various substrates and the ceramics La{sub 0.99}Ce{sub 0.01}B{sub 6}.

  12. Toxicity of Cerium Oxide Nanoparticles in Human Lung Cancer Cells

    SciTech Connect

    Weisheng, Lin; Huang, Yue-wern; Zhou, Xiao Dong; Ma, Yinfa

    2006-12-31

    With the fast development of nanotechnology, the nanomaterials start to cause people's attention for potential toxic effect. In this paper, the cytotoxicity and oxidative stress caused by 20-nm cerium oxide (CeO2) nanoparticles in cultured human lung cancer cells was investigated. The sulforhodamine B method was employed to assess cell viability after exposure to 3.5, 10.5, and 23.3 μg/ml of CeO2 nanoparticles for 24, 48, and 72 h. Cell viability decreased significantly as a function of nanoparticle dose and exposure time. Indicators of oxidative stress and cytotoxicity, including total reactive oxygen species, glutathione, malondialdehyde, α-tocopherol, and lactate dehydrogenase, were quantitatively assessed. It is concluded from the results that free radicals generated by exposure to 3.5 to 23.3 μg/ml CeO2 nanoparticles produce significant oxidative stress in the cells, as reflected by reduced glutathione and α-tocopherol levels; the toxic effects of CeO2 nanoparticles are dose dependent and time dependent; elevated oxidative stress increases the production of malondialdehyde and lactate dehydrogenase, which are indicators of lipid peroxidation and cell membrane damage, respectively.

  13. Antioxidant Cerium Oxide Nanoparticles in Biology and Medicine.

    PubMed

    Nelson, Bryant C; Johnson, Monique E; Walker, Marlon L; Riley, Kathryn R; Sims, Christopher M

    2016-05-17

    Previously, catalytic cerium oxide nanoparticles (CNPs, nanoceria, CeO2-x NPs) have been widely utilized for chemical mechanical planarization in the semiconductor industry and for reducing harmful emissions and improving fuel combustion efficiency in the automobile industry. Researchers are now harnessing the catalytic repertoire of CNPs to develop potential new treatment modalities for both oxidative- and nitrosative-stress induced disorders and diseases. In order to reach the point where our experimental understanding of the antioxidant activity of CNPs can be translated into useful therapeutics in the clinic, it is necessary to evaluate the most current evidence that supports CNP antioxidant activity in biological systems. Accordingly, the aims of this review are three-fold: (1) To describe the putative reaction mechanisms and physicochemical surface properties that enable CNPs to both scavenge reactive oxygen species (ROS) and to act as antioxidant enzyme-like mimetics in solution; (2) To provide an overview, with commentary, regarding the most robust design and synthesis pathways for preparing CNPs with catalytic antioxidant activity; (3) To provide the reader with the most up-to-date in vitro and in vivo experimental evidence supporting the ROS-scavenging potential of CNPs in biology and medicine.

  14. Antioxidant cerium oxide nanoparticle hydrogels for cellular encapsulation.

    PubMed

    Weaver, Jessica D; Stabler, Cherie L

    2015-04-01

    Oxidative stress and the resulting radical by-products cause significant toxicity and graft loss in cellular transplantation. Here, the engineering of an auto-catalytic, antioxidant, self-renewing cerium oxide nanoparticle (CONP)-composite hydrogel is reported. This enzyme-mimetic material ubiquitously scavenges ambient free radicals, with the potential to provide indefinite antioxidant protection. The potential of this system to enhance the protection of encapsulated beta cells was evaluated. Co-incubation of CONPs free in solution with beta cells demonstrated potent cytoprotection from superoxide exposure; however, phagocytosis of the CONPs by the beta cells resulted in cytotoxicity at concentrations as low as 1mM. When CONPs were embedded within alginate hydrogels, the composite hydrogel provided cytoprotection to encapsulated beta cells from free radical attack without cytotoxicity, even up to 10mM. This nanocomposite hydrogel has wide applicability in cellular transplantation, with the unique advantage of localization of these potent antioxidant CONPs and their capacity for sustained, long-term scavenging. PMID:25620795

  15. Catalytic Properties and Biomedical Applications of Cerium Oxide Nanoparticles

    PubMed Central

    Walkey, Carl; Das, Soumen; Seal, Sudipta; Erlichman, Joseph; Heckman, Karin; Ghibelli, Lina; Traversa, Enrico; McGinnis, James F.; Self, William T.

    2014-01-01

    Cerium oxide nanoparticles (Nanoceria) have shown promise as catalytic antioxidants in the test tube, cell culture models and animal models of disease. However given the reactivity that is well established at the surface of these nanoparticles, the biological utilization of Nanoceria as a therapeutic still poses many challenges. Moreover the form that these particles take in a biological environment, such as the changes that can occur due to a protein corona, are not well established. This review aims to summarize the existing literature on biological use of Nanoceria, and to raise questions about what further study is needed to apply this interesting catalytic material to biomedical applications. These questions include: 1) How does preparation, exposure dose, route and experimental model influence the reported effects of Nanoceria in animal studies? 2) What are the considerations to develop Nanoceria as a therapeutic agent in regards to these parameters? 3) What biological targets of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are relevant to this targeting, and how do these properties also influence the safety of these nanomaterials? PMID:26207185

  16. Antioxidant Cerium Oxide Nanoparticle Hydrogels for Cellular Encapsulation

    PubMed Central

    Weaver, Jessica D; Stabler, Cherie L

    2015-01-01

    Oxidative stress and the resulting radical by-products cause significant toxicity and graft loss in cellular transplantation. Here, the engineering of an auto-catalytic, antioxidant, self-renewing cerium oxide nanoparticle (CONP)-composite hydrogel is reported. This enzyme-mimetic material ubiquitously scavenges ambient free radicals, with the potential to provide indefinite antioxidant protection. Here, we evaluated the potential of this system to enhance the protection of encapsulated beta cells. Co-incubation of CONPs, free in solution with beta cells, demonstrated potent cytoprotection from superoxide exposure; however, phagocytosis of the CONPs by the beta cells resulted in cytotoxicity at concentrations as low as 1 mM. When CONPs were embedded within alginate hydrogels, the composite hydrogel provided cytoprotection to encapsulated beta cells from free radical attack without cytotoxicity, even up to 10 mM concentrations. This nanocomposite hydrogel has wide applicability in cellular transplantation, with the unique advantage of localization of these potent antioxidant CONPs and their capacity for sustained, long-term scavenging. PMID:25620795

  17. Langley 8-Ft. HTT Test 139 Gas Analyses

    NASA Technical Reports Server (NTRS)

    Sprinkle, Danny R.; Davis, Patricia P.

    1999-01-01

    This report presents results of gas analyses of Mach 7 Tunnel Calibration Test 139 conducted in the Langley 8-Ft. HTT from May through June of 1998. These tests in support of hypersonic airbreathing propulsion provided a current calibration at the primary test condition for the National Aero-Space Plane Concept Demonstration Engine and a new calibration for the two test conditions that will be used for engine testing in support of the Hyper-X program. Samples taken from three probes on the Flow Survey Apparatus were analyzed using mass spectrometers. Although this wind tunnel doesn't produce a true simulation of flight conditions, test results show that a uniform oxygen concentration of 21 percent was achieved.

  18. Vibrio cholerae O139 in Calcutta, 1992-1998: incidence, antibiograms, and genotypes.

    PubMed Central

    Basu, A.; Garg, P.; Datta, S.; Chakraborty, S.; Bhattacharya, T.; Khan, A.; Ramamurthy, S.; Bhattacharya, S. K.; Yamasaki, S.; Takeda, Y.; Nair, G. B.

    2000-01-01

    We report results of surveillance for cholera caused by Vibrio cholerae O139 from September 1992, when it was first identified, to December 1998. V. cholerae O139 dominated as the causative agent of cholera in Calcutta during 1992-93 and 1996- 97, while the O1 strains dominated during the rest of the period. Dramatic shifts in patterns of resistance to cotrimoxazole, neomycin, and streptomycin were observed. Molecular epidemiologic studies showed clonal diversity among the O139 strains and continuous emergence of new epidemic clones, reflected by changes in the structure, organization, and location of the CTX prophages in the V. cholerae O139 PMID:10756147

  19. THERMAL EFFECTS ON MASS AND SPATIAL RESOLUTION DURING LASER PULSE ATOM PROBE TOMOGRAPHY OF CERIUM OXIDE

    SciTech Connect

    Rita Kirchhofer; Melissa C. Teague; Brian P. Gorman

    2013-05-01

    Cerium oxide (CeO2) is an ideal surrogate material for trans-uranic elements and fission products found in nuclear fuels due to similarities in their thermal properties; therefore, cerium oxide was used to determine the best run condition for atom probe tomography (APT). Laser pulse APT is a technique that allows for spatial resolution in the nm scale and isotopic/elemental chemical identification. A systematic study of the impact of laser pulse energy and specimen base temperature on the mass resolution, measurement of stoichiometry, multiples, and evaporation mechanisms are reported in this paper. It was demonstrated that using laser pulse APT stoichiometric field evaporation of cerium oxide was achieved at 1 pJ laser pulse energy and 20 K specimen base temperature.

  20. Synthesis and characterization of cerium and yttrium alkoxide complexes supported by ferrocene-based chelating ligands.

    PubMed

    Broderick, Erin M; Thuy-Boun, Peter S; Guo, Neng; Vogel, Carola S; Sutter, Jörg; Miller, Jeffrey T; Meyer, Karsten; Diaconescu, Paula L

    2011-04-01

    Two series of Schiff base metal complexes were investigated, where each series was supported by an ancillary ligand incorporating a ferrocene backbone and different N=X functionalities. One ligand is based on an imine, while the other is based on an iminophosphorane group. Cerium(IV), cerium(III), and yttrium(III) alkoxide complexes supported by the two ligands were synthesized. All metal complexes were characterized by cyclic voltammetry. Additionally, NMR, Mössbauer, X-ray absorption near-edge structure (XANES), and absorption spectroscopies were used. The experimental data indicate that iron remains in the +2 oxidation state and that cerium(IV) does not engage in a redox behavior with the ancillary ligand.

  1. Photoemission of the Oxidation of Cerium Overlayers on GaSb(110) Surface

    NASA Astrophysics Data System (ADS)

    Liang, Qi; Wu, Jian-xin; Ji, Ming-rong; Ma, Mao-sheng; Liu, Xian-ming; Zhang, Yu-heng

    1997-10-01

    We have used x-ray photoelectron spectroscopy to study the oxidation of cerium overlayers on a semiconductor GaSb(110) surface. A GaSb(110) sample covered with 10 monolayers Ce was used to adsorb oxygen. When the exposure of O2 was up to 50 L, the oxide of cerium, Ce2O3, began to change into unstable CeO2. The dissociation of CeO2 resulted in strong oxidation of the substrate. The main products are Ga2O3, Sb2O3, and then Sb2O5. After annealing, a part of the oxygen atoms transferred from cerium dioxide toward Ga and Sb.

  2. Excitation induced spectroscopic study and quenching effect in cerium samarium codoped lithium aluminoborate glasses

    NASA Astrophysics Data System (ADS)

    Kaur, Parvinder; Kaur, Simranpreet; Singh, Gurinder Pal; Arora, Deepawali; Kumar, Sunil; Singh, D. P.

    2016-08-01

    Lithium aluminium borate host has been codoped with cerium and samarium to prepare glass by conventional melt quench technique. Their structural and spectroscopic investigation has been carried out using XRD, FTIR and density measurements. The UV-Vis absorption spectra and fluorescence spectra (λexc.=380 nm and 400 nm) have been studied for spectroscopic analysis. The amorphous nature of the prepared samples is shown by XRD. The density is increasing with addition of cerium at the expense of aluminium, keeping other components constant. FTIR study also shows the presence of compact and stable tetrahedral BO4 units thus supporting the density results. The UV- Vis absorption spectra show a shift of optical absorption edge towards longer wavelength along with an increase in intensity of peaks with rising samarium concentration. The fluorescence spectra show a blue shift and subsequent suppression of cerium peaks with addition of samarium.

  3. Development of graphene-nanometre-sized cerium oxide-incorporated aluminium and its electrochemical evaluation

    NASA Astrophysics Data System (ADS)

    Ashraf, P. Muhamed; Thomas, Saly N.; Edwin, Leela

    2016-02-01

    Graphene-nanometre-sized cerium oxide-incorporated aluminium was prepared and its electrochemical and surface morphological characteristics were studied. The atomic force micrographs and scanning electron micrographs evaluation highlighted that the graphene and nanometre-sized cerium oxide in aluminium had decreased the surface roughness and improved the surface morphological characteristics. The graphene: nanometre-sized cerium oxide (ratios 1:2 or 2:1) with lesser amounts of particle in the matrix showed excellent corrosion resistance in the marine environment as evidenced by linear polarization, electrochemical impedance and weight loss studies. Introduction of graphene in the aluminium matrix showed a barrier separation between the outermost layer and inner layer, increased roughness and increased corrosion. The material is found to be a potential candidate for use in marine environment.

  4. Fabrication of Cerium Oxide and Uranium Oxide Microspheres for Space Nuclear Power Applications

    SciTech Connect

    Jeffrey A. Katalenich; Michael R. Hartman; Robert C. O'Brien

    2013-02-01

    Cerium oxide and uranium oxide microspheres are being produced via an internal gelation sol-gel method to investigate alternative fabrication routes for space nuclear fuels. Depleted uranium and non-radioactive cerium are being utilized as surrogates for plutonium-238 (Pu-238) used in radioisotope thermoelectric generators and for enriched uranium required by nuclear thermal rockets. While current methods used to produce Pu-238 fuels at Los Alamos National Laboratory (LANL) involve the generation of fine powders that pose a respiratory hazard and have a propensity to contaminate glove boxes, the sol-gel route allows for the generation of oxide microsphere fuels through an aqueous route. The sol-gel method does not generate fine powders and may require fewer processing steps than the LANL method with less operator handling. High-quality cerium dioxide microspheres have been fabricated in the desired size range and equipment is being prepared to establish a uranium dioxide microsphere production capability.

  5. Green synthesized cerium oxide nanoparticle: A prospective drug against oxidative harm.

    PubMed

    Dutta, Debanjan; Mukherjee, Riya; Patra, Mousumi; Banik, Milon; Dasgupta, Rakhi; Mukherjee, Manabendra; Basu, Tarakdas

    2016-11-01

    Cerium oxide nanoparticle (CeONP) of size 2-3nm was synthesized by a new, simple and green method at ambient temperature, using cerium nitrate as prime precursor and Aloe vera leaf extract as stabilizing agent. Of the two oxidation states (+3) and (+4) of cerium, it was dominantly present in (+3) state in CeONP and cyclic conversion of Ce(III)O→Ce(IV)O→Ce(III)O by reaction with H2O2 implied uninterrupted antioxidant property of CeONP. Moreover, the higher oxygen defect in the crystal lattice produced particles with higher antioxidant activity. CeONP was found to neutralize the deleterious effects of H2O2 viz., cell death, generation of intracellular reactive oxygen species and loss of connectivity in mouse neural cells. Therefore, CeONP might have potential use in future as an anti-oxidant drug.

  6. Eucalyptus tolerance mechanisms to lanthanum and cerium: subcellular distribution, antioxidant system and thiol pools.

    PubMed

    Shen, Yichang; Zhang, Shirong; Li, Sen; Xu, Xiaoxun; Jia, Yongxia; Gong, Guoshu

    2014-12-01

    Guanglin 9 (Eucalyptus grandis × Eucalyptus urophlla) and Eucalyptus grandis 5 are two eucalyptus species which have been found to grow normally in soils contaminated with lanthanum and cerium, but the tolerance mechanisms are not clear yet. In this study, a pot experiment was conducted to investigate the tolerance mechanisms of the eucalyptus to lanthanum and cerium. Cell walls stored 45.40-63.44% of the metals under lanthanum or cerium stress. Peroxidase and catalase activities enhanced with increasing soil La or Ce concentrations up to 200 mg kg(-1), while there were no obvious changes in glutathione and ascorbate concentrations. Non-protein thiols concentrations increased with increasing treatment levels up to 200 mg kg(-1), and then decreased. Phytochelatins concentrations continued to increase under La or Ce stress. Therefore, the two eucalyptus species are La and Ce tolerant plants, and the tolerance mechanisms include cell wall deposition, antioxidant system response, and thiol compound synthesis. PMID:25303462

  7. Green synthesized cerium oxide nanoparticle: A prospective drug against oxidative harm.

    PubMed

    Dutta, Debanjan; Mukherjee, Riya; Patra, Mousumi; Banik, Milon; Dasgupta, Rakhi; Mukherjee, Manabendra; Basu, Tarakdas

    2016-11-01

    Cerium oxide nanoparticle (CeONP) of size 2-3nm was synthesized by a new, simple and green method at ambient temperature, using cerium nitrate as prime precursor and Aloe vera leaf extract as stabilizing agent. Of the two oxidation states (+3) and (+4) of cerium, it was dominantly present in (+3) state in CeONP and cyclic conversion of Ce(III)O→Ce(IV)O→Ce(III)O by reaction with H2O2 implied uninterrupted antioxidant property of CeONP. Moreover, the higher oxygen defect in the crystal lattice produced particles with higher antioxidant activity. CeONP was found to neutralize the deleterious effects of H2O2 viz., cell death, generation of intracellular reactive oxygen species and loss of connectivity in mouse neural cells. Therefore, CeONP might have potential use in future as an anti-oxidant drug. PMID:27478962

  8. Synthesis and photocatalytic activity of mesoporous cerium doped TiO{sub 2} as visible light sensitive photocatalyst

    SciTech Connect

    Aman, Noor; Satapathy, P.K.; Mishra, T.; Mahato, M.; Das, N.N.

    2012-02-15

    Graphical abstract: Cerium doped titania having optimum 5 wt% of cerium can decompose methylene blue and reduce selenium (IV) efficiently under visible light. Highlights: Black-Right-Pointing-Pointer Effect of cerium doping on the surface properties and visible light mediated photocatalytic reaction is studied. Black-Right-Pointing-Pointer Cerium doping increases the anatase phase stability, surface area (up to 137 m{sup 2}/g) and visible light absorption. Black-Right-Pointing-Pointer Importance of Ce{sup 3+}/Ce{sup 4+}, oxygen vacancy, surface area and crystallinity is correlated with improved catalytic activity. Black-Right-Pointing-Pointer Material with 5 wt% Ce is found to be most active photocatalyst for methylene blue decomposition and Se (IV) reduction. -- Abstract: Cerium doped titania materials were synthesized varying the cerium concentration from 0 to 10 wt%. Materials are characterised by XRD, TEM, XPS and N{sub 2} adsorption desorption method. Surface area and visible light absorption substantially increases and crystallite size decreases with the increasing cerium content. Cerium doping stabilizes the anatase phase and surface area even at 600 Degree-Sign C calcination. Photocatalytic activity towards methylene blue decomposition and selenium (IV) reduction is found to increase with the cerium content up to 5 wt% and then decreases. Materials calcined at 600 Degree-Sign C shows better activity than that calcined at 400 Degree-Sign C, even though surface area decreases. Anatase crystallinity mostly decides the photocatalytic activity rather than only surface area. It can be concluded that the optimum visible light absorption and oxygen vacancy with 5% cerium doping enhances the photocatalytic activity. In addition photocatalytic performance is found to depend on the presence of Ce{sup 4+}/Ce{sup 3+} rather than only visible light absorption.

  9. Ab initio studies of anisotropic magnetism in uranium and cerium monopnictides and monochalcogenides

    NASA Astrophysics Data System (ADS)

    Collins, Eric Mason

    We have applied two ab initio based methods to investigate the origin in the electronic structure of the unusual magnetic behavior of the cerium and uranium monopnictides and monochalcogenides. First, we have carried out spin-polarized electronic structure calculations, based on the full potential linear muffin tin (FPLMTO) method, with spin polarization (orbital polarization only via spin-orbit coupling) and also with orbital polarization correction. Second, we have carried out ab initio based calculations synthesizing (1) a phenomenological theory of orbitally driven magnetism based on the Anderson and Kondo, lattice model which incorporates explicitly the hybridization induced and the Coulomb exchange interactions on an equal footing, and (2) FPLMTO electronic structure calculations allowing a first principles evaluation of all the parameters entering the model Hamiltonian. For the cerium compounds, we also include the crystal field interactions on an equal footing with the hybridization and Coulomb exchange interactions with a scaling determined by experiment. The results for the uranium compound calculations show that both methods are limited to the extremes to which they are best suited. The pure band structure calculations provide the best agreement for the lighter uranium compounds, while the model hamiltonian approach provides better agreement for the heavier uranium compounds. In the case of the cerium compounds, while the pure FPLMTO calculations yield values for the magnetic moment in agreement with experiment for the lighter cerium chalcogenides, they fail to give, even qualitatively, the magnetic properties for all other systems. On the other hand, the ab initio based model Hamiltonian calculations reveal for the first time the interplay of hybridization, Coulomb exchange, and crystal field interactions across the cerium series, and give results for the low-temperature moment and ordering temperature in excellent agreement with experiment, for the

  10. The investigation of cerium as a cathodic inhibitor for aluminum-copper alloys

    SciTech Connect

    Aldykewicz, A.J. Jr.; Isaacs, H.S.; Davenport, A.J.

    1995-10-01

    In situ current density mapping, scanning electron microscopy , and energy dispersive spectroscopy were used to study the effects of cerium as a corrosion inhibitor for an aluminum copper alloy (Al 2024-T4) in chloride containing solutions. It was found that cerium inhibits corrosion of this alloy by reducing the rate of the cathodic reaction. This was due to the carried out on an aluminum/copper galvanic couple, which was used to simulate the electrochemical behavior of the copper containing intermetallics, showed that corrosion inhibition was associated with the formation of a Ce-rich film over the copper in agreement with that observed for the alloy.

  11. Synthesis and characterization of two dimensional metal organic framework of cerium with tetraaza macrocyclic

    SciTech Connect

    Bt Safiin, Nurul Atikah; Yarmo, Ambar; Yamin, Bohari M.

    2013-11-27

    A two dimensional metal organic framework containing cerium sufate layers and ethylenediaminium between layers was obtained by refluxing the mixture of cerium sulphate and 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-7, 14-diene bromide. The complex was characterized by infrared spectroscopy and microelemental analysis. X-ray study showed that the complex adopts eleven coordination environments about the central atom. Thermogravimetric study showed the removal of water molecules at about 70°C followed by a gradual mass loss until the whole structure collapsed at about 400°C.

  12. METHOD OF SEPARATING TETRAVALENT PLUTONIUM VALUES FROM CERIUM SUB-GROUP RARE EARTH VALUES

    DOEpatents

    Duffield, R.B.; Stoughton, R.W.

    1959-02-01

    A method is presented for separating plutonium from the cerium sub-group of rare earths when both are present in an aqueous solution. The method consists in adding an excess of alkali metal carbonate to the solution, which causes the formation of a soluble plutonium carbonate precipitate and at the same time forms an insoluble cerium-group rare earth carbonate. The pH value must be adjusted to bctween 5.5 and 7.5, and prior to the precipitation step the plutonium must be reduced to the tetravalent state since only tetravalent plutonium will form the soluble carbonate complex.

  13. Systematic variation of rare-earth elements in cerium-earth minerals

    USGS Publications Warehouse

    Murata, K.J.; Rose, H.J.; Carron, M.K.; Glass, J.J.

    1957-01-01

    In a continuation of a study reported previously, rare-earth elements and thorium have been determined in monazite, allanite, cerite, bastnaesite, and a number of miscellaneous cerium-earth minerals. A quantity called sigma (???), which is the sum of the atomic percentages of La, Ce, and Pr, is proposed as an index of composition of all cerium-earth minerals with respect to the rare-earth elements. The value of ??? for all of the minerals analysed falls between 58 and 92 atomic per cent. Monazites, allanites, and cerites cover the entire observed range, whereas bastnaesites are sharply restricted to the range between 80 and 92 atomic per cent. The minimum value of ??? for a cerium-earth mineral corresponds to the smallest possible unit-cell size of the mineral. In monazite, this structurally controlled minimum value of ??? is estimated to be around 30 atomic per cent. Neodymium, because of its abundance, and yttrium, because of its small size, have dominant roles in contraction of the structure. In the other direction, the limit of variation in composition will be reached when lanthanum becomes the sole rare-earth element in a cerium-earth mineral. Cerium-earth minerals from alkalic rocks are all characterized by values of ??? greater than 80 atomic per cent, indicating that the processes that formed these rocks were unusually efficient in fractionating the rare-earth elements-efficient in the sense that a highly selected assemblage is produced without eliminating the bulk of these elements. Analyses of inner and outer parts of two large crystals of monazite from different deposits show no difference in ??? in one crystal and a slightly smaller value of ??? in the outer part of the other crystal compared to the inner part. The ??? of monazites from pegmatites that intrude genetically related granitic rocks in North Carolina is found to be either higher or lower than the ??? of monazites in the intruded host rock. These results indicate that the fractionation of the

  14. Variations in Reactivity on Different Crystallographic Orientations of Cerium Oxide

    SciTech Connect

    Mullins, David R; Albrecht, Peter M; Calaza, Florencia C

    2013-01-01

    Cerium oxide is a principal component in many heterogeneous catalytic processes. One of its key characteristics is the ability to provide or remove oxygen in chemical reactions. The different crystallographic faces of ceria present significantly different surface structures and compositions that may alter the catalytic reactivity. The structure and composition determine the number of coordination vacancies surrounding surface atoms, the availability of adsorption sites, the spacing between adsorption sites and the ability to remove O from the surface. To investigate the role of surface orientation on reactivity, CeO2 films were grown with two different orientations. CeO2(100) films were grown ex situ by pulsed laser deposition on Nb-doped SrTiO3(100). CeO2(111) films were grown in situ by thermal deposition of Ce metal onto Ru(0001) in an oxygen atmosphere. The chemical reactivity was characterized by the adsorption and decomposition of various molecules such as alcohols, aldehydes and organic acids. In general the CeO2(100) surface was found to be more active, i.e. molecules adsorbed more readily and reacted to form new products, especially on a fully oxidized substrate. However the CeO2(100) surface was less selective with a greater propensity to produce CO, CO2 and water as products. The differences in chemical reactivity are discussed in light of possible structural terminations of the two surfaces. Recently nanocubes and nano-octahedra have been synthesized that display CeO2(100) and CeO2(111) faces, respectively. These nanoparticles enable us to correlate reactions on high surface area model catalysts at atmospheric pressure with model single crystal films in a UHV environment.

  15. Effect of cerium oxide nanoparticles on intestinal serotonin in zebrafish

    PubMed Central

    Özel, Rıfat Emrah; Hayat, Akhtar; Wallace, Kenneth N.; Andreescu, Silvana

    2013-01-01

    Cerium oxide nanoparticles or nanoceria are emerging as a new and promising class of nanoparticle technology for biomedical applications. The safe implementation of these particles in clinical applications requires evaluation of their redox properties and reactivity that might cause neurotoxic effects by interacting with redox components of the physiological environment. We report in vitro and in vivo studies to evaluate the impact of nanoceria exposure on serotonin (5-HT), an important neurotransmitter that plays a critical role in various physiological processes including motility and secretion in the digestive system. In vitro studies of 5-HT in the presence of nanoceria using spectroscopic, electrochemical and surface characterization methods demonstrate that nanoceria interacts with 5-HT and forms a surface adsorbed 5-HT-nanoceria complex. Further in vivo studies in live zebrafish embryos indicate depletion of the 5-HT level in the intestine for exposure periods longer than three days. Intestinal 5-HT was assessed quantitatively in live embryos using implantable carbon fiber microelectrodes and the results were compared to immunohistochemistry of the dissected intestine. 20 and 50 ppm nanoparticle exposure decreased the 5-HT level to 20.5 (±1.3) and 5.3 (±1.5) nM respectively as compared to 30.8 (±3.4) nM for unexposed control embryos. The results suggest that internalized nanoceria particles can concentrate 5-HT at the nanoparticle accumulation site depleting it from the surrounding tissue. This finding might have long term implications in the neurophysiology and functional development of organisms exposed to these particles through intended or unintended exposure. PMID:24015353

  16. Cerium oxide nanoparticle treatment ameliorates peritonitis-induced diaphragm dysfunction

    PubMed Central

    Asano, Shinichi; Arvapalli, Ravikumar; Manne, Nandini DPK; Maheshwari, Mani; Ma, Bing; Rice, Kevin M; Selvaraj, Vellaisamy; Blough, Eric R

    2015-01-01

    The severe inflammation observed during sepsis is thought to cause diaphragm dysfunction, which is associated with poor patient prognosis. Cerium oxide (CeO2) nanoparticles have been posited to exhibit anti-inflammatory and antioxidative activities suggesting that these particles may be of potential use for the treatment of inflammatory disorders. To investigate this possibility, Sprague Dawley rats were randomly assigned to the following groups: sham control, CeO2 nanoparticle treatment only (0.5 mg/kg iv), sepsis, and sepsis+CeO2 nanoparticles. Sepsis was induced by the introduction of cecal material (600 mg/kg) directly into the peritoneal cavity. Nanoparticle treatment decreased sepsis-associated impairments in diaphragmatic contractile (Po) function (sham: 25.6±1.6 N/cm2 vs CeO2: 23.4±0.8 N/cm2 vs Sep: 15.9±1.0 N/cm2 vs Sep+CeO2: 20.0±1.0 N/cm2, P<0.05). These improvements in diaphragm contractile function were accompanied by a normalization of protein translation signaling (Akt, FOXO-1, and 4EBP1), diminished proteolysis (caspase 8 and ubiquitin levels), and decreased inflammatory signaling (Stat3 and iNOS). Histological analysis suggested that nanoparticle treatment was associated with diminished sarcolemma damage and diminished inflammatory cell infiltration. These data indicate CeO2 nanoparticles may improve diaphragmatic function in the septic laboratory rat. PMID:26491293

  17. Effect of cerium oxide nanoparticles on intestinal serotonin in zebrafish.

    PubMed

    Ozel, Rıfat Emrah; Hayat, Akhtar; Wallace, Kenneth N; Andreescu, Silvana

    2013-09-21

    Cerium oxide nanoparticles or nanoceria are emerging as a new and promising class of nanoparticle technology for biomedical applications. The safe implementation of these particles in clinical applications requires evaluation of their redox properties and reactivity that might cause neurotoxic effects by interacting with redox components of the physiological environment. We report in vitro and in vivo studies to evaluate the impact of nanoceria exposure on serotonin (5-HT), an important neurotransmitter that plays a critical role in various physiological processes including motility and secretion in the digestive system. In vitro studies of 5-HT in the presence of nanoceria using spectroscopic, electrochemical and surface characterization methods demonstrate that nanoceria interacts with 5-HT and forms a surface adsorbed 5-HT-nanoceria complex. Further in vivo studies in live zebrafish embryos indicate depletion of the 5-HT level in the intestine for exposure periods longer than three days. Intestinal 5-HT was assessed quantitatively in live embryos using implantable carbon fiber microelectrodes and the results were compared to immunohistochemistry of the dissected intestine. 20 and 50 ppm nanoparticle exposure decreased the 5-HT level to 20.5 (±1.3) and 5.3 (±1.5) nM respectively as compared to 30.8 (±3.4) nM for unexposed control embryos. The results suggest that internalized nanoceria particles can concentrate 5-HT at the nanoparticle accumulation site depleting it from the surrounding tissue. This finding might have long term implications in the neurophysiology and functional development of organisms exposed to these particles through intended or unintended exposure. PMID:24015353

  18. Effects of Cerium Oxide Nanoparticles on Sorghum Plant Traits

    NASA Astrophysics Data System (ADS)

    Mu, L.; Chen, Y.; Darnault, C. J. G.; Rauh, B.; Kresovich, S.; Korte, C.

    2015-12-01

    Nanotechnology and nanomaterials are considered as the development of the modern science. However, besides with that wide application, nanoparticles arouse to the side effects on the environment and human health. As the catalyst of ceramics and fuel industry, Cerium (IV) oxide nanoparticles (CeO2 NPs) can be found in the environment following their use and life-cycle. Therefore, it is critical to assess the potential effects that CeO2 NPs found in soils may have on plants. In this study, CeO2 NPs were analyzed for the potential influence on the sorghum [Sorghum bicolor (L.) Moench] (Reg. no. 126) (PI 154844) growth and traits. The objectives of this research were to determine whether CeO2 NPs impact the sorghum germination and growth characteristics. The sorghum was grown in the greenhouse located at Biosystems Research Complex, Clemson University under different CeO2 NPs treatments (0mg; 100mg; 500mg; 1000mg CeO2 NPs/Kg soil) and harvested around each month. At the end of the each growing period, above ground vegetative tissue was air-dried, ground to 2mm particle size and compositional traits estimated using near-infrared spectroscopy. Also, the NPK value of the sorghum tissue was tested by Clemson Agriculture Center. After the first harvest, the result showed that the height of above ground biomass under the nanoparticles stress was higher than that of control group. This difference between the control and the nanoparticles treatments was significant (F>F0.05; LSD). Our results also indicated that some of the compositional traits were impacted by the different treatments, including the presence and/or concentrations of the nanoparticles.

  19. 46 CFR 108.139 - Boundary bulkheads and decks of a space containing emergency power.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... bulkhead and deck of a space containing an emergency electric power source or components of an emergency electric power source must be an A class bulkhead and A class deck respectively. When separate but... emergency power. 108.139 Section 108.139 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)...

  20. 34 CFR 668.139 - Recovery of payments and loan disbursements to ineligible students.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ineligible students. 668.139 Section 668.139 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION STUDENT ASSISTANCE GENERAL... Federal Perkins loan fund or Federal Pell Grant, ACG, National SMART Grant, TEACH Grant, FSEOG, or...

  1. 34 CFR 668.139 - Recovery of payments and loan disbursements to ineligible students.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ineligible students. 668.139 Section 668.139 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION STUDENT ASSISTANCE GENERAL... Federal Perkins loan fund or Federal Pell Grant, ACG, National SMART Grant, TEACH Grant, FSEOG, or...

  2. 10 CFR 1.39 - Office of the Chief Human Capital Officer.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Office of the Chief Human Capital Officer. 1.39 Section 1... Headquarters Staff Offices § 1.39 Office of the Chief Human Capital Officer. The Office of the Chief Human... effective organization, utilization, and development of the agency's human resources; (b) Provides...

  3. 10 CFR 26.139 - Reporting initial validity and drug test results.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Reporting initial validity and drug test results. 26.139... § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall... permitted under § 26.75(h), positive test results from initial drug tests at the licensee testing...

  4. 22 CFR 139.7 - Qualifications for participation as an employer in the United States.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... in the United States. 139.7 Section 139.7 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH... the United States. To participate in the Irish Peace Process Cultural and Training Program, U.S... followed. (f) Notify the Program Administrator in the event of the termination of a participant...

  5. 22 CFR 139.7 - Qualifications for participation as an employer in the United States.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... in the United States. 139.7 Section 139.7 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH... the United States. To participate in the Irish Peace Process Cultural and Training Program, U.S... followed. (f) Notify the Program Administrator in the event of the termination of a participant...

  6. 22 CFR 139.7 - Qualifications for participation as an employer in the United States.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... in the United States. 139.7 Section 139.7 Foreign Relations DEPARTMENT OF STATE MISCELLANEOUS IRISH... the United States. To participate in the Irish Peace Process Cultural and Training Program, U.S... followed. (f) Notify the Program Administrator in the event of the termination of a participant...

  7. 14 CFR 1264.139 - Stays ordered by the Department of Justice.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Stays ordered by the Department of Justice. 1264.139 Section 1264.139 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Justice. If at any time the Attorney General or an Assistant Attorney General designated by the...

  8. 14 CFR 1264.139 - Stays ordered by the Department of Justice.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Stays ordered by the Department of Justice. 1264.139 Section 1264.139 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Justice. If at any time the Attorney General or an Assistant Attorney General designated by the...

  9. 14 CFR 1264.139 - Stays ordered by the Department of Justice.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Stays ordered by the Department of Justice. 1264.139 Section 1264.139 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Justice. If at any time the Attorney General or an Assistant Attorney General designated by the...

  10. 14 CFR 1264.139 - Stays ordered by the Department of Justice.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Stays ordered by the Department of Justice. 1264.139 Section 1264.139 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Justice. If at any time the Attorney General or an Assistant Attorney General designated by the...

  11. 14 CFR § 1264.139 - Stays ordered by the Department of Justice.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Stays ordered by the Department of Justice. § 1264.139 Section § 1264.139 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... Justice. If at any time the Attorney General or an Assistant Attorney General designated by the...

  12. 25 CFR 139.4 - Deferment of assessments on lands remaining in Indian ownership.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Deferment of assessments on lands remaining in Indian ownership. 139.4 Section 139.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES REIMBURSEMENT OF CONSTRUCTION COSTS, WAPATO-SATUS UNIT, WAPATO INDIAN IRRIGATION...

  13. 25 CFR 139.5 - Assessments after the Indian title has been extinguished.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Assessments after the Indian title has been extinguished. 139.5 Section 139.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES REIMBURSEMENT OF CONSTRUCTION COSTS, WAPATO-SATUS UNIT, WAPATO INDIAN IRRIGATION PROJECT, WASHINGTON §...

  14. 25 CFR 1000.139 - Will the established indirect cost rates always apply to new AFAs?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 2 2014-04-01 2014-04-01 false Will the established indirect cost rates always apply to new AFAs? 1000.139 Section 1000.139 Indians OFFICE OF THE ASSISTANT SECRETARY, INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ANNUAL FUNDING AGREEMENTS UNDER THE TRIBAL SELF-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT...

  15. 25 CFR 1000.139 - Will the established indirect cost rates always apply to new AFAs?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 2 2013-04-01 2013-04-01 false Will the established indirect cost rates always apply to new AFAs? 1000.139 Section 1000.139 Indians OFFICE OF THE ASSISTANT SECRETARY, INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ANNUAL FUNDING AGREEMENTS UNDER THE TRIBAL SELF-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF-DETERMINATION AND EDUCATION ACT...

  16. Lanthanum-139 nuclear magnetic resonance studies of polyaminocarboxylate-lanthanum complexes in aqueous solution

    NASA Astrophysics Data System (ADS)

    Geraldes, Carlos F. G. C.; Dean Sherry, A.

    Several complexes of La(III) with aminocarboxylate and polyaminocarboxylate ligands in aqueous solution have been studied using 139La chemical-shift and linewidth measurements. The ligand-induced shifts of the 139La NMR resonance were found to depend, at least to first order, on additive substituent contributions, and were empirically related to the number and type of coordinated oxygen and nitrogen atoms. A previously proposed relationship between the number of coordinated carboxylate oxygen atoms and observed 139La shifts does not seem to hold for the polyaminocarboxylate complexes and we propose a new empirical relationship which allows an accurate prediction of the number and types of ligand donors in these systems. The 139La linewidths also provide qualitative information about the symmetry of each La 3+ chelate. The results show that 139La NMR can be a powerful technique for elucidating the structure and dynamics of lanthanide complexes in solution.

  17. Cerium Oxide Nanoparticles and Bulk Cerium Oxide Leading to Different Physiological and Biochemical Responses in Brassica rapa.

    PubMed

    Ma, Xingmao; Wang, Qiang; Rossi, Lorenzo; Zhang, Weilan

    2016-07-01

    Cerium oxide nanoparticles (CeO2NPs) have been incorporated into many commercial products, and their potential release into the environment through the use and disposal of these products has caused serious concerns. Despite the previous efforts and rapid progress on elucidating the environmental impact of CeO2NPs, the long-term impact of CeO2NPs to plants, a key component of the ecosystem, is still not well understood. The potentially different impact of CeO2NPs and their bulk counterparts to plants is also unclear. The main objectives of this study were (1) to investigate whether continued irrigation with solutions containing different concentrations of CeO2NPs (0, 10, and 100 mg/L) would induce physiological and biochemical adjustments in Brassica rapa in soil growing conditions and (2) to determine whether CeO2NPs and bulk CeO2 particles exert different impacts on plants. The results indicated that bulk CeO2 at 10 and 100 mg/L enhanced plant biomass by 28% and 35%, respectively, while CeO2NPs at equivalent concentrations did not. While the bulk CeO2 treatment resulted in significantly higher concentrations of hydrogen peroxide (H2O2) in plant tissues at the vegetative stage, CeO2NPs led to significantly higher H2O2 levels in plant tissues at the floral stage. The activity of superoxide dismutase (SOD) in Brassica rapa also displayed a growth-stage dependent response to different sizes of CeO2 while catalase (CAT) activity was not affected by either size of CeO2 throughout the life cycle of Brassica rapa. Altogether, the results demonstrated that plant responses to CeO2 exposure varied with the particle sizes and the growth stages of plants.

  18. Cerium Oxide Nanoparticles and Bulk Cerium Oxide Leading to Different Physiological and Biochemical Responses in Brassica rapa.

    PubMed

    Ma, Xingmao; Wang, Qiang; Rossi, Lorenzo; Zhang, Weilan

    2016-07-01

    Cerium oxide nanoparticles (CeO2NPs) have been incorporated into many commercial products, and their potential release into the environment through the use and disposal of these products has caused serious concerns. Despite the previous efforts and rapid progress on elucidating the environmental impact of CeO2NPs, the long-term impact of CeO2NPs to plants, a key component of the ecosystem, is still not well understood. The potentially different impact of CeO2NPs and their bulk counterparts to plants is also unclear. The main objectives of this study were (1) to investigate whether continued irrigation with solutions containing different concentrations of CeO2NPs (0, 10, and 100 mg/L) would induce physiological and biochemical adjustments in Brassica rapa in soil growing conditions and (2) to determine whether CeO2NPs and bulk CeO2 particles exert different impacts on plants. The results indicated that bulk CeO2 at 10 and 100 mg/L enhanced plant biomass by 28% and 35%, respectively, while CeO2NPs at equivalent concentrations did not. While the bulk CeO2 treatment resulted in significantly higher concentrations of hydrogen peroxide (H2O2) in plant tissues at the vegetative stage, CeO2NPs led to significantly higher H2O2 levels in plant tissues at the floral stage. The activity of superoxide dismutase (SOD) in Brassica rapa also displayed a growth-stage dependent response to different sizes of CeO2 while catalase (CAT) activity was not affected by either size of CeO2 throughout the life cycle of Brassica rapa. Altogether, the results demonstrated that plant responses to CeO2 exposure varied with the particle sizes and the growth stages of plants. PMID:26691446

  19. The effects of cerium doping on the size, morphology, and optical properties of α-hematite nanoparticles for ultraviolet filtration

    SciTech Connect

    Cardillo, Dean; Konstantinov, Konstantin; Devers, Thierry

    2013-11-15

    Highlights: • Possible application of cerium-doped α-hematite as ultraviolet filter. • Nanoparticles obtained through co-precipitation technique using various cerium doping levels followed by annealing. • Comprehensive materials characterisation utilizing XRD, DSC/TGA, STEM, UV–vis spectroscopy. • Increasing cerium content reduces particle sizing and alters morphology. • Solubility of cerium in hematite seen between 5 and 10% doping, 10% cerium doping greatly enhances attenuation in ultraviolet region and increases optical bandgap. - Abstract: Metal oxide nanoparticles have potential use in energy storage, electrode materials, as catalysts and in the emerging field of nanomedicine. Being able to accurately tailor the desirable properties of these nanoceramic materials, such as particle size, morphology and optical bandgap (E{sub g}) is integral in the feasibility of their use. In this study we investigate the altering of both the structure and physical properties through the doping of hematite (α-Fe{sub 2}O{sub 3}) nanocrystals with cerium at a range of concentrations, synthesised using a one-pot co-precipitation method. This extremely simple synthesis followed by thermal treatment results in stable Fe{sub 2−x}Ce{sub x}O{sub y} nanoceramics resulting from the burning of any unreacted precursors and transformation of goethite-cerium doped nanoparticle intermediate. The inclusion of Ce into the crystal lattice of these α-Fe{sub 2}O{sub 3} nanoparticles causes a significantly large reduction in mean crystalline size and alteration in particle morphology with increasing cerium content. Finally we report an increase optical semiconductor bandgap, along with a substantial increase in the ultraviolet attenuation found for a 10% Ce-doping concentration which shows the potential application of cerium-doped hematite nanocrystals to be used as a pigmented ultraviolet filter for cosmetic products.

  20. Synthesis and characterization of linear cerium(IV) Schiff-base coordination polymers

    SciTech Connect

    Chen, H.; Cronin, J.A.; Archer, R.D. . Dept. of Chemistry)

    1994-04-11

    The first soluble linear Schiff-base rare earth coordination polymer, catena-poly[cerium-(4)-[mu]-N,N[prime],N[double prime],N[prime][double prime]-tetrasalicylidene (3,3[prime]-diaminobenzidinato)-O,N,N[prime],O[prime],O[double prime],N[double prime],N[prime][double prime],O[prime][double prime

  1. Cerium (IV) oxide nanotubes prepared by low temperature deposition at normal pressure.

    PubMed

    Boehme, M; Fu, G; Ionescu, E; Ensinger, W

    2011-02-11

    This paper reports the synthesis of cerium dioxide nanotubes (CeNTs) by electroless deposition using ion-track-etched polycarbonate templates. To achieve nanotubes with thin walls and small surface roughness the tubes were generated by a several-step-containing procedure under aqueous conditions. The approach reported below will process open end nanotubes with well-defined outer diameter and wall thickness.

  2. Pits confined in ultrathin cerium(IV) oxide for studying catalytic centers in carbon monoxide oxidation

    NASA Astrophysics Data System (ADS)

    Sun, Yongfu; Liu, Qinghua; Gao, Shan; Cheng, Hao; Lei, Fengcai; Sun, Zhihu; Jiang, Yong; Su, Haibin; Wei, Shiqiang; Xie, Yi

    2013-11-01

    Finding ideal material models for studying the role of catalytic active sites remains a great challenge. Here we propose pits confined in an atomically thin sheet as a platform to evaluate carbon monoxide catalytic oxidation at various sites. The artificial three-atomic-layer thin cerium(IV) oxide sheet with approximately 20% pits occupancy possesses abundant pit-surrounding cerium sites having average coordination numbers of 4.6 as revealed by X-ray absorption spectroscopy. Density-functional calculations disclose that the four- and five-fold coordinated pit-surrounding cerium sites assume their respective role in carbon monoxide adsorption and oxygen activation, which lowers the activation barrier and avoids catalytic poisoning. Moreover, the presence of coordination-unsaturated cerium sites increases the carrier density and facilitates carbon monoxide diffusion along the two-dimensional conducting channels of surface pits. The atomically thin sheet with surface-confined pits exhibits lower apparent activation energy than the bulk material (61.7 versus 122.9 kJ mol-1), leading to reduced conversion temperature and enhanced carbon monoxide catalytic ability.

  3. Fabrication and characterization of cerium-doped barium titanate inverse opal by sol-gel method

    SciTech Connect

    Jin Yi; Zhu Yihua Yang Xiaoling; Li Chunzhong; Zhou Jinghong

    2007-01-15

    Cerium-doped barium titanate inverted opal was synthesized from barium acetate contained cerous acetate and tetrabutyl titanate in the interstitial spaces of a polystyrene (PS) opal. This procedure involves infiltration of precursors into the interstices of the PS opal template followed by hydrolytic polycondensation of the precursors to amorphous barium titanate and removal of the PS opal by calcination. The morphologies of opal and inverse opal were characterized by scanning electron microscope (SEM). The pores were characterized by mercury intrusion porosimetry (MIP). X-ray photoelectron spectroscopy (XPS) investigation showed the doping structure of cerium, barium and titanium. And powder X-ray diffraction allows one to observe the influence of doping degree on the grain size. The lattice parameters, crystal size and lattice strain were calculated by the Rietveld refinement method. The synthesis of cerium-doped barium titanate inverted opals provides an opportunity to electrically and optically engineer the photonic band structure and the possibility of developing tunable three-dimensional photonic crystal devices. - Graphical abstract: Cerium-doped barium titanate inverted opal was synthesized from barium acetate acid contained cerous acetate and tetrabutyl titanate in the interstitial spaces of a PS opal, which involves infiltration of precursors into the interstices of the PS opal template and removal of the PS opal by calcination.

  4. Calculation of the volume effect at an electron phase transition in pure cerium and praseodymium

    NASA Astrophysics Data System (ADS)

    Ponomareva, S. A.; Koval', Yu. N.; Ponomarev, A. P.

    2014-03-01

    The experimental values of the volume effect at an electronic phase transition in several rare-earth metals are discussed. Specifically, volume changes at phase transitions in cerium and praseodymium are calculated using a semiphenomenological relationship derived in terms of the Falikov-Ramirez-Kimball model. A number of factors influencing the amount of the volume effect at electronic phase transitions are analyzed.

  5. Synthesis, electrical and dielectric characterization of cerium doped nano copper ferrites

    SciTech Connect

    Malana, Muhammad Aslam Qureshi, Raheela Beenish; Ashiq, Muhammad Naeem; Zafar, Zafar Iqbal

    2013-11-15

    Graphical abstract: Lattice constant (a) and activation energy (Ea) as a function of Ce (cerium) content. - Highlights: • The simple and economic method has been adopted for the synthesis of nanoferrites. • The electrical resistivity increases with cerium concentration. • DC electrical resistivity of these materials favours their use in microwave devices. • Dielectric measurements show semiconductor nature of the synthesized ferrites. - Abstract: The nanosized CuFe{sub 2−x}Ce{sub x}O{sub 4} (x = 0.0, 0.2, 0.4, 0.6, 0.8) ferrites doped with cerium are synthesized by chemical co-precipitation method. The synthesized materials are characterized by XRD, FTIR, TGA and SEM. XRD analysis of cerium substituted copper ferrites confirms the cubic spinel structure. The average crystallite size calculated by using Scherrer's formula ranges from 37 to 53 nm. The values of cell constant and cell volume vary with the dopant concentration. These variations can be explained in terms of their ionic radii. The DC electrical resistivity, measured by two point probe method, increases with increase in dopant concentration while it decreases with rise in temperature exhibiting semiconductor behaviour. Energy of activation of these ferrites is calculated by using Arrhenius type resistivity plots. Dielectric measurements of the synthesized compounds show exponential decrease in dielectric constant and dielectric loss factor with increase in frequency. This indicates the normal dielectric behaviour of ferrites.

  6. Phenotypic and genomic responses to titanium dioxide and cerium oxide nanoparticles in Arabidopsis germinants

    EPA Science Inventory

    The effects of exposure to two nanoparticles (NPs) -titanium dioxide (nano-titania) and cerium oxide (nano-ceria) at 500 mg NPs L-1 on gene expression and growth in Arabidopsis thaliana germinants were studied using microarrays and phenotype studies. After 12 days post treatment,...

  7. Cyclic thermochemical process for producing hydrogen using cerium-titanium compounds

    DOEpatents

    Bamberger, Carlos E.

    1980-01-01

    A thermochemical cyclic process for producing hydrogen employs the reaction between ceric oxide and titanium dioxide to form cerium titanate and oxygen. The titanate is treated with an alkali metal hydroxide to give hydrogen, ceric oxide, an alkali metal titanate and water. Alkali metal titanate and water are boiled to give titanium dioxide which, along with ceric oxide, is recycled.

  8. Cyclic thermochemical process for producing hydrogen using cerium-titanium compounds

    DOEpatents

    Bamberger, C.E.

    A thermochemical cyclic process for producing hydrogen employs the reaction between ceric oxide and titanium dioxide to form cerium titanate and oxygen. The titanate is treated with an alkali metal hydroxide to give hydrogen, ceric oxide, an alkali metal titanate and water. Alkali metal titanate and water are boiled to give titanium dioxide which, along with ceric oxide, is recycled.

  9. Pits confined in ultrathin cerium(IV) oxide for studying catalytic centers in carbon monoxide oxidation.

    PubMed

    Sun, Yongfu; Liu, Qinghua; Gao, Shan; Cheng, Hao; Lei, Fengcai; Sun, Zhihu; Jiang, Yong; Su, Haibin; Wei, Shiqiang; Xie, Yi

    2013-01-01

    Finding ideal material models for studying the role of catalytic active sites remains a great challenge. Here we propose pits confined in an atomically thin sheet as a platform to evaluate carbon monoxide catalytic oxidation at various sites. The artificial three-atomic-layer thin cerium(IV) oxide sheet with approximately 20% pits occupancy possesses abundant pit-surrounding cerium sites having average coordination numbers of 4.6 as revealed by X-ray absorption spectroscopy. Density-functional calculations disclose that the four- and five-fold coordinated pit-surrounding cerium sites assume their respective role in carbon monoxide adsorption and oxygen activation, which lowers the activation barrier and avoids catalytic poisoning. Moreover, the presence of coordination-unsaturated cerium sites increases the carrier density and facilitates carbon monoxide diffusion along the two-dimensional conducting channels of surface pits. The atomically thin sheet with surface-confined pits exhibits lower apparent activation energy than the bulk material (61.7 versus 122.9 kJ mol(-1)), leading to reduced conversion temperature and enhanced carbon monoxide catalytic ability.

  10. Cerium oxide coated anodes for aluminum electrowinning: Topical report, October 1, 1986-June 30, 1987

    SciTech Connect

    Walker, J. K.

    1987-12-01

    Because of the cost of building and maintaining a carbon anode plant and the energy penalties associated with the use of carbon anodes in the production of aluminum, the use of inert anodes has long been proposed. Various cermet anodes have been investigated. In this paper, tests on a material, cerium oxyfluoride (CEROX), deposited in situ as an anode, are reported. (JDH)

  11. Demonstration of enhanced K-edge angiography using a cerium target x-ray generator

    SciTech Connect

    Sato, Eiichi; Tanaka, Etsuro; Mori, Hidezo; Kawai, Toshiaki; Ichimaru, Toshio; Sato, Shigehiro; Takayama, Kazuyoshi; Ido, Hideaki

    2004-11-01

    The cerium target x-ray generator is useful in order to perform enhanced K-edge angiography using a cone beam because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast mediums. The x-ray generator consists of a main controller, a unit with a Cockcroft-Walton circuit and a fixed anode x-ray tube, and a personal computer. The tube is a glass-enclosed diode with a cerium target and a 0.5-mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.0x1.3 mm. Cerium K{alpha} lines were left using a barium sulfate filter, and the x-ray intensity was 0.48 {mu}C/kg at 1.0 m from the source with a tube voltage of 60 kV, a current of 0.40 mA, and an exposure time of 1.0 s. Angiography was performed with a computed radiography system using iodine-based microspheres. In coronary angiography of nonliving animals, we observed fine blood vessels of approximately 100 {mu}m with high contrasts.

  12. Phosphate ester hydrolysis of biologically relevant molecules by cerium oxide nanoparticles.

    PubMed

    Kuchma, Melissa Hirsch; Komanski, Christopher B; Colon, Jimmie; Teblum, Andrew; Masunov, Artëm E; Alvarado, Beatrice; Babu, Suresh; Seal, Sudipta; Summy, Justin; Baker, Cheryl H

    2010-12-01

    In an effort to characterize the interaction of cerium oxide nanoparticles (CNPs) in biological systems, we explored the reactivity of CNPs with the phosphate ester bonds of p-nitrophenylphosphate (pNPP), ATP, o-phospho-l-tyrosine, and DNA. The activity of the bond cleavage for pNPP at pH 7 is calculated to be 0.860 ± 0.010 nmol p-nitrophenol/min/μg CNPs. Interestingly, when CNPs bind to plasmid DNA, no cleavage products are detected. While cerium(IV) complexes generally exhibit the ability to break phosphorus-oxygen bonds, the reactions we report appear to be dependent on the availability of cerium(III) sites, not cerium(IV) sites. We investigated the dephosphorylation mechanism from the first principles and find the reaction proceeds through inversion of the phosphate group similar to an S(N)2 mechanism. The ability of CNPs to interact with phosphate ester bonds of biologically relevant molecules has important implications for their use as potential therapeutics.

  13. Long range ordered alloys modified by addition of niobium and cerium

    DOEpatents

    Liu, C.T.

    1984-08-22

    Long range ordered alloys are described having the nominal composition (Fe,Ni,Co)/sub 3/ (V,M) where M is a ductility enhancing metal selected from the group Ti, Zr, Hf with additions of small amounts of cerium and niobium to dramatically enhance the creep properties of the resulting alloys.

  14. Long range ordered alloys modified by addition of niobium and cerium

    DOEpatents

    Liu, Chain T.

    1987-01-01

    Long range ordered alloys are described having the nominal composition (Fe,Ni,Co).sub.3 (V,M) where M is a ductility enhancing metal selected from the group Ti, Zr, Hf with additions of small amounts of cerium and niobium to drammatically enhance the creep properties of the resulting alloys.

  15. Resonant photoemission study of the 4f spectral function of cerium in Ce/Fe(100) interfaces

    SciTech Connect

    Witkowski, N.; Bertran, F.; Gourieux, T.; Kierren, B.; Malterre, D.; Panaccione, G. |

    1997-11-01

    In this paper, we present a resonant photoemission study of the cerium 4f spectral function in Ce/Fe(100) interfaces. By covering cerium ultrathin films with lanthanum, we completely suppress the surface contribution of the spectra. Then we show that the cerium atoms at the interface are in an intermediate valent state, whereas the f{sup 1} configuration is stabilized in the top layer. This method allows us to obtain the genuine 4f spectral function of the interface, and could be extended to a study of Ce-based compounds. {copyright} {ital 1997} {ital The American Physical Society}

  16. 4d → 4f resonance in photoabsorption of cerium ion Ce3+ and endohedral cerium in fullerene complex {\\rm{Ce}}@{{{\\rm{C}}}_{82}}^{+}

    NASA Astrophysics Data System (ADS)

    Schrange-Kashenock, G.

    2016-09-01

    The theoretical investigation of the single-photoionization spectra in the 4d-resonance region (120-150 eV) for the ionic cerium Ce3+ and cerium in the endohedral complex {{Ce}}@{{{{C}}}82}+ (in practice, {{{Ce}}}3+@{{{{C}}}82}2-) is presented. The fullerene cage is modeled by ab initio spherical jellium shell with an accurate account for the real distribution of carbon electron density. The oscillator strengths are calculated within the multiconfiguration Dirac-Fock (MCDF) approach for phototransitions from the outermost shells of the ion Ce3+ with and without the influence of the potential generated by a fullerene cage. It is shown that the integrated oscillator strengths have the main contribution from the Ce3+ 4d → 4f (ten possible from the phototransitions {}2F{7/2,5/2}\\to {}2D{3/2,5/2},{}2F{5/2,7/2},{}2G{5/2,7/2}) resonance photoexcitations. The corresponding precise MCDF values for the oscillator strengths and the transition energies are presented for the first time. It is demonstrated that the resonance {f}4d\\to 4f oscillator strengths are slightly affected by the presence of the cage potential, despite the fact that the spectral levels structure is changed when the effect of this potential is included. The Auger 4d -1 decay from the cerium free ion Ce3+ and the encapsulated endohedral ion Ce3+@ are considered within the two-step model and the corresponding Lorentzian profiles are presented. This model clearly reveals the correspondence of the complex resonance profile in the Ce3+ photoabsorption to the fine structure of ion energy levels. The smoothing of the resonance profile in the photoabsorption of the endohedral system {{Ce}}@{{{{C}}}82}+ compared with the free ion Ce3+ is attributed to increasing the linewidths of the Auger transitions. This increase is estimated from the relevant experiment (Müller et al 2008 Phys. Rev. Lett. 101 133001) to be strong; as at least three times the value for an isolated ion. The presence of the confining fullerene

  17. 4d → 4f resonance in photoabsorption of cerium ion Ce3+ and endohedral cerium in fullerene complex {\\rm{Ce}}@{{{\\rm{C}}}_{82}}^{+}

    NASA Astrophysics Data System (ADS)

    Schrange-Kashenock, G.

    2016-09-01

    The theoretical investigation of the single-photoionization spectra in the 4d-resonance region (120–150 eV) for the ionic cerium Ce3+ and cerium in the endohedral complex {{Ce}}@{{{{C}}}82}+ (in practice, {{{Ce}}}3+@{{{{C}}}82}2-) is presented. The fullerene cage is modeled by ab initio spherical jellium shell with an accurate account for the real distribution of carbon electron density. The oscillator strengths are calculated within the multiconfiguration Dirac–Fock (MCDF) approach for phototransitions from the outermost shells of the ion Ce3+ with and without the influence of the potential generated by a fullerene cage. It is shown that the integrated oscillator strengths have the main contribution from the Ce3+ 4d → 4f (ten possible from the phototransitions {}2F{7/2,5/2}\\to {}2D{3/2,5/2},{}2F{5/2,7/2},{}2G{5/2,7/2}) resonance photoexcitations. The corresponding precise MCDF values for the oscillator strengths and the transition energies are presented for the first time. It is demonstrated that the resonance {f}4d\\to 4f oscillator strengths are slightly affected by the presence of the cage potential, despite the fact that the spectral levels structure is changed when the effect of this potential is included. The Auger 4d ‑1 decay from the cerium free ion Ce3+ and the encapsulated endohedral ion Ce3+@ are considered within the two-step model and the corresponding Lorentzian profiles are presented. This model clearly reveals the correspondence of the complex resonance profile in the Ce3+ photoabsorption to the fine structure of ion energy levels. The smoothing of the resonance profile in the photoabsorption of the endohedral system {{Ce}}@{{{{C}}}82}+ compared with the free ion Ce3+ is attributed to increasing the linewidths of the Auger transitions. This increase is estimated from the relevant experiment (Müller et al 2008 Phys. Rev. Lett. 101 133001) to be strong; as at least three times the value for an isolated ion. The presence of the confining

  18. Cerium, uranium, and plutonium behavior in glass-bonded sodalite, a ceramic nuclear waste form.

    SciTech Connect

    Lewis, M. A.; Lexa, D.; Morss, L. R.; Richmann, M. K.

    1999-09-03

    Glass-bonded sodalite is being developed as a ceramic waste form (CWF) to immobilize radioactive fission products, actinides, and salt residues from electrometallurgical treatment of spent nuclear reactor fuel. The CWF consists of about 75 mass % sodalite, 25 mass % glass, and small amounts of other phases. This paper presents some results and interpretation of physical measurements to characterize the CWF structure, and dissolution tests to measure the release of matrix components and radionuclides from the waste form. Tests have been carried out with specimens of the CWF that contain rare earths at concentrations similar to those expected in the waste form. Parallel tests have been carried out on specimens that have uranium or plutonium as well as the rare earths at concentrations similar to those expected in the waste forms; in these specimens UCl{sub 3} forms UO{sub 2} and PuCl{sub 3} forms PuO{sub 2}. The normalized releases of rare earths in dissolution tests were found to be much lower than those of matrix elements (B, Si, Al, Na). When there is no uranium in the CWF, the release of cerium is two to ten times lower than the release of the other rare earths. The low release of cerium may be due to its tetravalent state in uranium-free CWF. However, when there is uranium in the CWF, the release of cerium is similar to that of the other rare earths. This trivalent behavior of cerium is attributed to charge transfer or covalent interactions among cerium, uranium, and oxygen in (U,Ce)O{sub 2}.

  19. Assessment of Contaminated Brine Fate and Transport in MB139 at WIPP

    SciTech Connect

    Kuhlman, Kristopher L.; Malama, Bwalya

    2014-07-01

    Following the radionuclide release event of February 14, 2014 at the Waste Isolation Pilot Plant (WIPP), actinide contamination has been found on the walls and floor in Panel 7 as a result of a release in Room 7 of Panel 7. It has been proposed to decontaminate Panel 7 at the WIPP by washing contaminated surfaces in the underground with fresh water. A cost-effective cleanup of this contamination would allow for a timely return to waste disposal operations at WIPP. It is expected that the fresh water used to decontaminate Panel 7 will flow as contaminated brine down into the porosity of the materials under the floor – the run-of-mine (ROM) salt above Marker Bed 139 (MB139) and MB139 itself – where its fate will be controlled by the hydraulic and transport properties of MB139. Due to the structural dip of MB139, it is unlikely that this brine would migrate northward towards the Waste-Handling Shaft sump. A few strategically placed shallow small-diameter observation boreholes straddling MB139 would allow for monitoring the flow and fate of this brine after decontamination. Additionally, given that flow through the compacted ROM salt floor and in MB139 would occur under unsaturated (or two-phase) conditions, there is a need to measure the unsaturated flow properties of crushed WIPP salt and salt from the disturbed rock zone (DRZ).

  20. Determination of K-capture Probability in the Decay of {sup 139}Ce

    SciTech Connect

    Ganbaatar, N.; Ichinkhorloo, D.; Tserenchimeg, E.

    2009-03-31

    We have been studying the KX and gamma rays spectra in the electron capture decay of {sup 139}Ce{yields}{sup 139}La, which were measured by Ge-spectrometer. The absolute intensity of KX and the 165.8 keV gamma rays has been determined and the known conversion coefficients of the 165.8 keV gamma transition of {sup 139}La were used. The probability P{sub K} was determined as 0.755{+-}0.054. Our results have good agreement with the results of other works.

  1. 17 CFR 1.39 - Simultaneous buying and selling orders of different principals; execution of, for and between...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... selling orders of different principals; execution of, for and between principals. 1.39 Section 1.39... COMMODITY EXCHANGE ACT Recordkeeping § 1.39 Simultaneous buying and selling orders of different principals... shall have in hand at the same time both buying and selling orders of different principals for the...

  2. 40 CFR 61.139 - Provisions for alternative means for process vessels, storage tanks, and tar-intercepting sumps.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... adsorber outlet vent reaches the maximum concentration point, as determined in § 61.139(h). (4) For each... defined in § 61.139(h)(5). (ii) For each non-regenerative carbon adsorber, an exceedance of the maximum... determined in § 61.139(h). (c) Compliance with the provisions of this section shall be determined as...

  3. 40 CFR 61.139 - Provisions for alternative means for process vessels, storage tanks, and tar-intercepting sumps.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... adsorber outlet vent reaches the maximum concentration point, as determined in § 61.139(h). (4) For each... defined in § 61.139(h)(5). (ii) For each non-regenerative carbon adsorber, an exceedance of the maximum... determined in § 61.139(h). (c) Compliance with the provisions of this section shall be determined as...

  4. Vibrio cholerae O139 conjugate vaccines: synthesis and immunogenicity of V. cholerae O139 capsular polysaccharide conjugates with recombinant diphtheria toxin mutant in mice.

    PubMed

    Kossaczka, Z; Shiloach, J; Johnson, V; Taylor, D N; Finkelstein, R A; Robbins, J B; Szu, S C

    2000-09-01

    Epidemiologic and experimental data provide evidence that a critical level of serum immunoglobulin G (IgG) antibodies to the surface polysaccharide of Vibrio cholerae O1 (lipopolysaccharide) and of Vibrio cholerae O139 (capsular polysaccharide [CPS]) is associated with immunity to the homologous pathogen. The immunogenicity of polysaccharides, especially in infants, may be enhanced by their covalent attachment to proteins (conjugates). Two synthetic schemes, involving 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 1-cyano-4-dimethylaminopyridinium tetrafluoroborate (CDAP) as activating agents, were adapted to prepare four conjugates of V. cholerae O139 CPS with the recombinant diphtheria toxin mutant, CRMH21G. Adipic acid dihydrazide was used as a linker. When injected subcutaneously into young outbred mice by a clinically relevant dose and schedule, these conjugates elicited serum CPS antibodies of the IgG and IgM classes with vibriocidal activity to strains of capsulated V. cholerae O139. Treatment of these sera with 2-mercaptoethanol (2-ME) reduced, but did not eliminate, their vibriocidal activity. These results indicate that the conjugates elicited IgG with vibriocidal activity. Conjugates also elicited high levels of serum diphtheria toxin IgG. Convalescent sera from 20 cholera patients infected with V. cholerae O139 had vibriocidal titers ranging from 100 to 3,200: absorption with the CPS reduced the vibriocidal titer of all sera to < or =50. Treatment with 2-ME reduced the titers of 17 of 20 patients to < or =50. These data show that, like infection with V. cholerae O1, infection with V. cholerae O139 induces vibriocidal antibodies specific to the surface polysaccharide of this bacterium (CPS) that are mostly of IgM class. Based on these data, clinical trials with the V. cholerae O139 CPS conjugates with recombinant diphtheria toxin are planned. PMID:10948122

  5. Radioactive waste forms stabilized by ChemChar gasification: characterization and leaching behavior of cerium, thorium, protactinium, uranium, and neptunium.

    PubMed

    Marrero, T W; Morris, J S; Manahan, S E

    2004-02-01

    The uses of a thermally reductive gasification process in conjunction with vitrification and cementation for the long-term disposal of low level radioactive materials have been investigated. gamma-ray spectroscopy was used for analysis of carrier-free protactinium-233 and neptunium-239 and a stoichiometric amount of cerium (observed cerium-141) subsequent to gasification and leaching, up to 48 days. High resolution ICP-MS was used to analyze the cerium, thorium, and uranium from 46 to 438 days of leaching. Leaching procedures followed the guidance of ASTM Procedure C 1220-92, Standard Test Method for Static Leaching of Monolithic Waste Forms for Disposal of Radioactive Waste. The combination of the thermally reductive pretreatment, vitrification and cementation produced a highly non-leachable form suitable for long-term disposal of cerium, thorium, protactinium, uranium, and neptunium.

  6. Radioactive waste forms stabilized by ChemChar gasification: characterization and leaching behavior of cerium, thorium, protactinium, uranium, and neptunium.

    PubMed

    Marrero, T W; Morris, J S; Manahan, S E

    2004-02-01

    The uses of a thermally reductive gasification process in conjunction with vitrification and cementation for the long-term disposal of low level radioactive materials have been investigated. gamma-ray spectroscopy was used for analysis of carrier-free protactinium-233 and neptunium-239 and a stoichiometric amount of cerium (observed cerium-141) subsequent to gasification and leaching, up to 48 days. High resolution ICP-MS was used to analyze the cerium, thorium, and uranium from 46 to 438 days of leaching. Leaching procedures followed the guidance of ASTM Procedure C 1220-92, Standard Test Method for Static Leaching of Monolithic Waste Forms for Disposal of Radioactive Waste. The combination of the thermally reductive pretreatment, vitrification and cementation produced a highly non-leachable form suitable for long-term disposal of cerium, thorium, protactinium, uranium, and neptunium. PMID:14637345

  7. A chemical-spectrochemical method for the determination of rare earth elements and thorium in cerium minerals

    USGS Publications Warehouse

    Rose, H.J.; Murata, K.J.; Carron, M.K.

    1954-01-01

    In a combined chemical-spectrochemical procedure for quantitatively determining rare earth elements in cerium minerals, cerium is determined volumetrically, a total rare earths plus thoria precipitate is separated chemically, the ceria content of the precipitate is raised to 80??0 percent by adding pure ceria, and the resulting mixture is analyzed for lanthanum, praseodymium, neodymium, samarium, gadolinium, yttrium, and thorium spectrochemically by means of the d.c. carbon arc. Spectral lines of singly ionized cerium are used as internal standard lines in the spectrochemical determination which is patterned after Fassel's procedure [1]. Results of testing the method with synthetic mixtures of rare earths and with samples of chemically analyzed cerium minerals show that the coefficient of variation for a quadruplicate determination of any element does not exceed 5??0 (excepting yttrium at concentrations less than 1 percent) and that the method is free of serious systematic error. ?? 1954.

  8. Vibrio cholerae phage K139: complete genome sequence and comparative genomics of related phages.

    PubMed

    Kapfhammer, Dagmar; Blass, Julia; Evers, Stefan; Reidl, Joachim

    2002-12-01

    In this report, we characterize the complete genome sequence of the temperate phage K139, which morphologically belongs to the Myoviridae phage family (P2 and 186). The prophage genome consists of 33,106 bp, and the overall GC content is 48.9%. Forty-four open reading frames were identified. Homology analysis and motif search were used to assign possible functions for the genes, revealing a close relationship to P2-like phages. By Southern blot screening of a Vibrio cholerae strain collection, two highly K139-related phage sequences were detected in non-O1, non-O139 strains. Combinatorial PCR analysis revealed almost identical genome organizations. One region of variable gene content was identified and sequenced. Additionally, the tail fiber genes were analyzed, leading to the identification of putative host-specific sequence variations. Furthermore, a K139-encoded Dam methyltransferase was characterized.

  9. Effects of ZNF139 on gastric cancer cells and mice with gastric tumors

    PubMed Central

    Nie, Hong-Feng; Li, Yong; Li, Zhen-Xing; Mu, Ji-Xing; Wang, Jin-Sheng

    2016-01-01

    Gastric cancer (GC) is the fourth most common type of cancer, worldwide. The major molecular factors associated with the pathogenesis of GC remain unclear. Previous studies found that zinc finger proteins are highly abundant in human eukaryotes and tissues, and play an important role in maintaining normal cellular functions and have an association with tumor initiation. In the current study, interference technology was used to silence the ZNF139 protein, a zinc finger protein that was previously found to be closely associated with GC. The results showed that cell viability and proliferation were inhibited in the Znf139-knockdown of GC cells. Additional study found that the expression levels of B cell lymphoma-2 (Bcl-2) and survivin messenger RNAs and proteins were downregulated in Znf139-silenced cells, indicating that cells expression Znf139 are able to induce the growth of tumor cells by mediating the apoptosis pathway. Further in vivo experiments showed that Znf139 knockdown downregulated the expression levels of Bcl-2 and survivin in mice. Overall, the in vitro and in vivo findings of the present study indicate that ZNF139 may be actively involved in the progression of GC.

  10. Protection of Primary Dopaminergic Midbrain Neurons by GPR139 Agonists Supports Different Mechanisms of MPP(+) and Rotenone Toxicity.

    PubMed

    Bayer Andersen, Kirsten; Leander Johansen, Jens; Hentzer, Morten; Smith, Garrick Paul; Dietz, Gunnar P H

    2016-01-01

    The G-protein coupled receptor 139 (GPR139) is expressed specifically in the brain in areas of relevance for motor control. GPR139 function and signal transduction pathways are elusive, and results in the literature are even contradictory. Here, we examined the potential neuroprotective effect of GPR139 agonism in primary culture models of dopaminergic (DA) neuronal degeneration. We find that in vitro GPR139 agonists protected primary mesencephalic DA neurons against 1-methyl-4-phenylpyridinium (MPP(+))-mediated degeneration. Protection was concentration-dependent and could be blocked by a GPR139 antagonist. However, the protection of DA neurons was not found against rotenone or 6-hydroxydopamine (6-OHDA) mediated degeneration. Our results support differential mechanisms of toxicity for those substances commonly used in Parkinson's disease (PD) models and potential for GPR139 agonists in neuroprotection. PMID:27445691

  11. Protection of Primary Dopaminergic Midbrain Neurons by GPR139 Agonists Supports Different Mechanisms of MPP+ and Rotenone Toxicity

    PubMed Central

    Bayer Andersen, Kirsten; Leander Johansen, Jens; Hentzer, Morten; Smith, Garrick Paul; Dietz, Gunnar P. H.

    2016-01-01

    The G-protein coupled receptor 139 (GPR139) is expressed specifically in the brain in areas of relevance for motor control. GPR139 function and signal transduction pathways are elusive, and results in the literature are even contradictory. Here, we examined the potential neuroprotective effect of GPR139 agonism in primary culture models of dopaminergic (DA) neuronal degeneration. We find that in vitro GPR139 agonists protected primary mesencephalic DA neurons against 1-methyl-4-phenylpyridinium (MPP+)-mediated degeneration. Protection was concentration-dependent and could be blocked by a GPR139 antagonist. However, the protection of DA neurons was not found against rotenone or 6-hydroxydopamine (6-OHDA) mediated degeneration. Our results support differential mechanisms of toxicity for those substances commonly used in Parkinson’s disease (PD) models and potential for GPR139 agonists in neuroprotection. PMID:27445691

  12. Long-term testing of in-situ cerium oxide coated anodes for aluminum electrowinning

    SciTech Connect

    King, H.L.

    1989-10-01

    The ELTECH Anode Phase 2 Project (Contract Number AC07-86ID12655), as supported by the Department of Energy (DOE) from December 1988 through April 1989, focused on long-term testing of in-situ anodically deposited cerium oxide (CEROX) coatings on nickel ferrite/Cu cermets. The specific objective of this research was to determine the effectiveness of the CEROX coating in reducing the transfer of cermet components to the produced aluminum. A dosing regimen was first established for the minimum addition of cerium to the cell necessary to produce targeted CEROX coatings on the cermet anode and the periodic additions necessary to maintain coating thicknesses. The effects of the addition of CeF{sub 3} on CEROX coating formation was evaluated for targeted coating thicknesses at three different current densities. Analytical procedures were identified for determining alumina concentrations and the cryolite bath ratio for quasi-commercial baths.

  13. A DFT + U study of cerium solubility in La₂Zr₂O₇

    SciTech Connect

    Wang, X. J.; Xiao, Haiyan Y.; Zu, Xiaotao; Weber, William J.

    2012-02-17

    Density functional theory plus Hubbard U correction is employed to study the solubility of cerium in La₂Zr₂O₇. The results show that La₂Zr₂O₇ and Ce₂Zr₂O₇ form a solid solution over the whole range of cerium content. The solubility of Ce in La₂Zr₂O₇ can be partially attributed to the similar ionic radii of La³+ and Ce³+. Electronic structures of the La₂₋yCeyZr₂O₇ solid solution have been analyzed. The Ce 4ƒ states are found to be partially occupied, and Ce in the La₂₋yCeyZr₂O₇ solid solution exhibits a reduced charge state.

  14. Cerium Binding Activity of Pectins Isolated from the Seagrasses Zostera marina and Phyllospadix iwatensis

    PubMed Central

    Khotimchenko, Yuri; Khozhaenko, Elena; Kovalev, Valeri; Khotimchenko, Maxim

    2012-01-01

    Cerium binding activity of three different water soluble pectin compounds of different origin was studied in a batch sorption system. The Langmuir, Freundlich and BET sorption models were adopted to describe the binding reactions between metal ions and pectin molecules. The Langmuir model provided the best fit. Within the pH range from 4.0 to 6.0, the largest amount of the cerium ions was bound by pectin isolated from the seagrass Phylospadix iwatensis in comparison to pectin extracted from the seagrass Zostera marina and pectin obtained from citrus peel (commercial grade). The Langmuir constants were also highest for the pectin samples isolated from the seagrass P. iwatensis. The results obtained from this study suggest that pectin is a prospective source for the development of radioisotope-removing pharmaceuticals. PMID:22690146

  15. Measurement of the magnetic behaviour of 147Eu and 149Eu in cerium and platinum

    NASA Astrophysics Data System (ADS)

    Dietrich, M.; Zeitz, W.-D.; Weber, A.; Potzger, K.; Unterricker, S.; Schneider, F.; Samokhvalov, V.; Isolde Collaboration

    2005-07-01

    The local magnetism at europium in platinum and in cerium was studied using perturbed angular correlation (PAC) spectroscopy. In platinum, europium shows the electronic properties of the trivalent status, which has a non-magnetic ground state ( J=0). As a consequence, the Van Vleck contributions from the complete multiplet-level system predominantly determine the magnetic behaviour. In cerium, the measured data are close to the predictions for divalent europium. Here, only the electronic ground state, the pure spin state ( J=5/2), has to be taken into account. The measurements were done utilising the isomeric 11/2 - nuclear levels in 147Eu and 149Eu at 625 and 496 keV, respectively, after the precursors had been produced at the ion beam laboratory ISL Berlin or the on-line mass separator ISOLDE in Geneva.

  16. Luminescent Properties of Cerium Doped Potassium Iodide Single Crystals in Response to γ-irradiation.

    PubMed

    Bangaru, S; Saradha, K; Muralidharan, G

    2015-05-01

    Potassium iodide doped with cerium ions were prepared by Bridgemann Stockbarger technique and investigated by optical absorption, Photoluminescence(PL), Thermoluminescence(TL), Photostimulated Luminescence(PSL) and TL emission. The optical absorption measurement indicates that F and V centers are formed in the crystals during the γ-ray irradiation process. Optical absorption and Photoluminescence studies confirm the presence of cerium ions in the trivalent state. Spectral distribution under the Thermoluminescence Emission(TLE) and Optically Stimulated Luminescence(OSL) support the idea that the defect annihilation process to be due to thermal release of F-electron in KI:Ce(3+) crystals. Both Ce(3+) and Ce(2+) emissions were observed in the Thermoluminescence emission of the crystals. Thermoluminescence(TL) has been identified to be due to thermal release of electron produced during colouration process. PMID:25744528

  17. Variation of electronic transitions and reduction potentials of cerium(IV) complexes.

    PubMed

    Williams, Ursula J; Schneider, David; Dorfner, Walter L; Maichle-Mössmer, Cäcilia; Carroll, Patrick J; Anwander, Reiner; Schelter, Eric J

    2014-11-21

    The trivalent compound K[Ce[N(SiHMe2)2]4] was synthesized and oxidized, providing a convenient route to the reported cerium(IV) compound Ce[N(SiHMe2)2]4. Protonolysis reactions of Ce[N(SiHMe2)2]4 with tert-butanol, substituted benzyl alcohols, and 2,6-diphenylphenol yielded the neutral tetravalent compounds Ce(O(t)Bu)4(py)2, Ce2(OCH2C6R5)8(thf)2 (R = Me, F), and Ce(Odpp)4 (dpp = 2,6-(C6H5)2-C6H3). Spectroscopic and electrochemical characterization of the monometallic cerium(IV) silylamide, alkoxide, and aryloxide compounds revealed variable ligand-to-metal charge transfer transitions and metal-based reduction potentials. Computational bonding analyses were performed to complement the physical characterization of the complexes.

  18. Thermodynamics of the α -γ transition in cerium studied by an LDA + Gutzwiller method

    NASA Astrophysics Data System (ADS)

    Tian, Ming-Feng; Song, Hai-Feng; Liu, Hai-Feng; Wang, Cong; Fang, Zhong; Dai, Xi

    2015-03-01

    Utilizing the local-density approximation (LDA) + Gutzwiller method, we have studied the α -γ transition in cerium. Our results indicate that the volume collapse transition between α and γ phases is present at zero temperature with negative pressure. By further providing a newly finite temperature generalization of the LDA + Gutzwiller method (using the mean-field potential approach), the entropy contributed by both electronic quasiparticles and lattice vibration included, we obtain the Gibbs free energy at a given volume and temperature, from which we get the α -γ transition at finite temperature and pressure. Our results indicate that the electronic entropy and lattice vibrational entropy both play important roles in the α -γ transition. We also calculated the equation of state and phase diagram of cerium, finding good agreement with the experiments.

  19. A cerium-lead redox flow battery system employing supporting electrolyte of methanesulfonic acid

    NASA Astrophysics Data System (ADS)

    Na, Zhaolin; Xu, Shengnan; Yin, Dongming; Wang, Limin

    2015-11-01

    A novel cerium-lead redox flow battery (RFB) employing Ce(IV)/Ce(III) and Pb(II)/Pb redox couples in the supporting electrolyte of methanesulfonic acid (MSA) is developed and preliminarily investigated. The RFB requires no additional catalyst and uses kinetically favorable reactions between low-cost reactants, and provides a desirable discharge voltage of approximately 1.7 V, with high average coulombic efficiency (CE) of 92% and energy efficiency (EE) of 86% over 800 cycles at 298 K. Stable cycling with an acceptable performance is achieved for a board operating temperature range of 253 K-313 K. The excellent performance obtained from the preliminary study suggests that the cerium-lead RFB promises to be applicable to large-scale energy storage for electricity grids.

  20. Improvement and analysis of the hydrogen-cerium redox flow cell

    NASA Astrophysics Data System (ADS)

    Tucker, Michael C.; Weiss, Alexandra; Weber, Adam Z.

    2016-09-01

    The H2-Ce redox flow cell is optimized using commercially-available cell materials. Cell performance is found to be sensitive to the upper charge cutoff voltage, membrane boiling pretreatment, methanesulfonic-acid concentration, (+) electrode surface area and flow pattern, and operating temperature. Performance is relatively insensitive to membrane thickness, Cerium concentration, and all features of the (-) electrode including hydrogen flow. Cell performance appears to be limited by mass transport and kinetics in the cerium (+) electrode. Maximum discharge power of 895 mW cm-2 was observed at 60 °C; an energy efficiency of 90% was achieved at 50 °C. The H2-Ce cell is promising for energy storage assuming one can optimize Ce reaction kinetics and electrolyte.

  1. Cerium Regulates Expression of Alternative Methanol Dehydrogenases in Methylosinus trichosporium OB3b

    PubMed Central

    Farhan Ul Haque, Muhammad; Kalidass, Bhagyalakshmi; Bandow, Nathan; Turpin, Erick A.; DiSpirito, Alan A.

    2015-01-01

    Methanotrophs have multiple methane monooxygenases that are well known to be regulated by copper, i.e., a “copper switch.” At low copper/biomass ratios the soluble methane monooxygenase (sMMO) is expressed while expression and activity of the particulate methane monooxygenase (pMMO) increases with increasing availability of copper. In many methanotrophs there are also multiple methanol dehydrogenases (MeDHs), one based on Mxa and another based on Xox. Mxa-MeDH is known to have calcium in its active site, while Xox-MeDHs have been shown to have rare earth elements in their active site. We show here that the expression levels of Mxa-MeDH and Xox-MeDH in Methylosinus trichosporium OB3b significantly decreased and increased, respectively, when grown in the presence of cerium but the absence of copper compared to the absence of both metals. Expression of sMMO and pMMO was not affected. In the presence of copper, the effect of cerium on gene expression was less significant, i.e., expression of Mxa-MeDH in the presence of copper and cerium was slightly lower than in the presence of copper alone, but Xox-MeDH was again found to increase significantly. As expected, the addition of copper caused sMMO and pMMO expression levels to significantly decrease and increase, respectively, but the simultaneous addition of cerium had no discernible effect on MMO expression. As a result, it appears Mxa-MeDH can be uncoupled from methane oxidation by sMMO in M. trichosporium OB3b but not from pMMO. PMID:26296730

  2. PURIFICATION OF PLUTONIUM USING A CERIUM PRECIPITATE AS A CARRIER FOR FISSION PRODUCTS

    DOEpatents

    Faris, B.F.; Olson, C.M.

    1961-07-01

    Bismuth phosphate carrier precipitation processes are described for the separation of plutonium from fission products wherein in at least one step bismuth phosphate is precipitated in the presence of hexavalent plutonium thereby carrying a portion of the fission products from soluble plu tonium values. In this step, a cerium phosphate precipitate is formed in conjunction with the bismuth phosphate precipitate, thereby increasing the amount of fission products removed from solution.

  3. Cerium regulates expression of alternative methanol dehydrogenases in Methylosinus trichosporium OB3b.

    PubMed

    Farhan Ul Haque, Muhammad; Kalidass, Bhagyalakshmi; Bandow, Nathan; Turpin, Erick A; DiSpirito, Alan A; Semrau, Jeremy D

    2015-11-01

    Methanotrophs have multiple methane monooxygenases that are well known to be regulated by copper, i.e., a "copper switch." At low copper/biomass ratios the soluble methane monooxygenase (sMMO) is expressed while expression and activity of the particulate methane monooxygenase (pMMO) increases with increasing availability of copper. In many methanotrophs there are also multiple methanol dehydrogenases (MeDHs), one based on Mxa and another based on Xox. Mxa-MeDH is known to have calcium in its active site, while Xox-MeDHs have been shown to have rare earth elements in their active site. We show here that the expression levels of Mxa-MeDH and Xox-MeDH in Methylosinus trichosporium OB3b significantly decreased and increased, respectively, when grown in the presence of cerium but the absence of copper compared to the absence of both metals. Expression of sMMO and pMMO was not affected. In the presence of copper, the effect of cerium on gene expression was less significant, i.e., expression of Mxa-MeDH in the presence of copper and cerium was slightly lower than in the presence of copper alone, but Xox-MeDH was again found to increase significantly. As expected, the addition of copper caused sMMO and pMMO expression levels to significantly decrease and increase, respectively, but the simultaneous addition of cerium had no discernible effect on MMO expression. As a result, it appears Mxa-MeDH can be uncoupled from methane oxidation by sMMO in M. trichosporium OB3b but not from pMMO. PMID:26296730

  4. Cerium Oxide Nanoparticles Reduce Microglial Activation and Neurodegenerative Events in Light Damaged Retina

    PubMed Central

    Fiorani, Lavinia; Passacantando, Maurizio; Santucci, Sandro; Di Marco, Stefano; Bisti, Silvia; Maccarone, Rita

    2015-01-01

    The first target of any therapy for retinal neurodegeneration is to slow down the progression of the disease and to maintain visual function. Cerium oxide or ceria nanoparticles reduce oxidative stress, which is known to play a pivotal role in neurodegeneration. Our aim was to investigate whether cerium oxide nanoparticles were able to mitigate neurodegeneration including microglial activation and related inflammatory processes induced by exposure to high intensity light. Cerium oxide nanoparticles were injected intravitreally or intraveinously in albino Sprague-Dawley rats three weeks before exposing them to light damage of 1000 lux for 24 h. Electroretinographic recordings were performed a week after light damage. The progression of retinal degeneration was evaluated by measuring outer nuclear layer thickness and TUNEL staining to quantify photoreceptors death. Immunohistochemical analysis was used to evaluate retinal stress, neuroinflammatory cytokines and microglial activation. Only intravitreally injected ceria nanoparticles were detected at the level of photoreceptor outer segments 3 weeks after the light damage and electoretinographic recordings showed that ceria nanoparticles maintained visual response. Moreover, this treatment reduced neuronal death and “hot spot” extension preserving the outer nuclear layer morphology. It is noteworthy that in this work we demonstrated, for the first time, the ability of ceria nanoparticles to reduce microglial activation and their migration toward outer nuclear layer. All these evidences support ceria nanoparticles as a powerful therapeutic agent in retinal neurodegenerative processes. PMID:26469804

  5. Application of cerium nitrate-silver sulphadiazine allows for postponement of excision and grafting.

    PubMed

    Vehmeyer-Heeman, M; Tondu, T; Van den Kerckhove, E; Boeckx, W

    2006-02-01

    Early excision and grafting cannot always be performed due to patient's medical status, and the lack of adequate donor sites. The use of cerium nitrate-silver sulphadiazine cream, which causes the formation of a leather-like eschar with excellent resistance to infection, is an alternative method. In order to postpone operations by using cerium nitrate-silver sulphadiazine, we compared the differences in contamination of the grafted areas between early and delayed excision. Eighteen patients underwent excision and grafting within 5 days post burn and nineteen patients were surgically treated after 5 days. Twelve months later the grafted areas were evaluated. Contamination of the grafted area occurred in 17 patients. No differences in contamination occurred between the early and delayed excision group, 8 versus 9. Also no differences in type of organism cultured and follow-up results were found between the early and delayed excision group. Cerium nitrate-silver sulphadiazine allows surgical treatment to be delayed without an increase of contamination of the grafted area and does not adversely affect the long-term outcome.

  6. Cerium Biomagnification in a Terrestrial Food Chain: Influence of Particle Size and Growth Stage.

    PubMed

    Majumdar, Sanghamitra; Trujillo-Reyes, Jesica; Hernandez-Viezcas, Jose A; White, Jason C; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2016-07-01

    Mass-flow modeling of engineered nanomaterials (ENMs) indicates that a major fraction of released particles partition into soils and sediments. This has aggravated the risk of contaminating agricultural fields, potentially threatening associated food webs. To assess possible ENM trophic transfer, cerium accumulation from cerium oxide nanoparticles (nano-CeO2) and their bulk equivalent (bulk-CeO2) was investigated in producers and consumers from a terrestrial food chain. Kidney bean plants (Phaseolus vulgaris var. red hawk) grown in soil contaminated with 1000-2000 mg/kg nano-CeO2 or 1000 mg/kg bulk-CeO2 were presented to Mexican bean beetles (Epilachna varivestis), which were then consumed by spined soldier bugs (Podisus maculiventris). Cerium accumulation in plant and insects was independent of particle size. After 36 days of exposure to 1000 mg/kg nano- and bulk-CeO2, roots accumulated 26 and 19 μg/g Ce, respectively, and translocated 1.02 and 1.3 μg/g Ce, respectively, to shoots. The beetle larvae feeding on nano-CeO2 exposed leaves accumulated low levels of Ce since ∼98% of Ce was excreted in contrast to bulk-CeO2. However, in nano-CeO2 exposed adults, Ce in tissues was higher than Ce excreted. Additionally, Ce content in tissues was biomagnified by a factor of 5.3 from the plants to adult beetles and further to bugs.

  7. Application of Cerium (IV) as an Oxidimetric Agent for the Determination of Ethionamide in Pharmaceutical Formulations

    PubMed Central

    2016-01-01

    Two simple methods are described for the determination of ethionamide (ETM) in bulk drug and tablets using cerium (IV) sulphate as the oxidimetric agent. In both methods, the sample solution is treated with a measured excess of cerium (IV) solution in H2SO4 medium, and after a fixed standing time, the residual oxidant is determined either by back titration with standard iron (II) solution to a ferroin end point in titrimetry or by reacting with o-dianisidine followed by measurement of the absorbance of the orange-red coloured product at 470 nm in spectrophotometry. In titrimetry, the reaction proceeded with a stoichiometry of 1 : 2 (ETM : Ce (IV)) and the amount of cerium (IV) consumed by ETM was related to the latter's amount, and the method was applicable over 1.0–8.0 mg of drug. In spectrophotometry, Beer's law was obeyed over the concentration range of 0.5–5.0 μg/mL ETM with a molar absorptivity value of 2.66 × 104 L/(mol·cm). The limits of detection (LOD) and quantification (LOQ) calculated according to ICH guidelines were 0.013 and 0.043 μg/mL, respectively. The proposed titrimetric and spectrophotometric methods were found to yield reliable results when applied to bulk drug and tablets analysis, and hence they can be applied in quality control laboratories.

  8. Unveiling the mechanism of uptake and sub-cellular distribution of cerium oxide nanoparticles†

    PubMed Central

    Singh, Sanjay; Kumar, Amit; Karakoti, Ajay; Seal, Sudipta; Self, William T.

    2011-01-01

    Cerium oxide nanoparticles (CNPs) have been recently studied for their potent superoxide scavenging properties in both cell and animal model systems. Data from these model systems have shown that exposure of cells to CNPs results in the protection against reactive oxygen species (ROS). Despite these exciting findings, very little is known regarding the uptake or subcellular distribution of these nanomaterials inside cells. In this study we utilized fluorophore (carboxyfluorescein) conjugated cerium oxide NPs (CCNPs) to study the mechanism of uptake and to elucidate the subcellular localization of CNPs using a keratinocyte model system. We observed rapid uptake (within 3 h) of CCNPs that was governed by energy-dependent, clathrin-mediated and caveolae-mediated endocytic pathways. We found CCNPs co-localized with mitochondria, lysosomes and endoplasmic reticulum as well as being abundant in the cytoplasm and the nucleus. Given the radical scavenging properties of cerium oxide and the widespread cellular disposition we observed, CNPs likely act as cellular antioxidants in multiple compartments of the cell imparting protection against a variety of oxidant injuries. PMID:20697616

  9. The role of hydrogen peroxide in the deposition of cerium-based conversion coatings

    NASA Astrophysics Data System (ADS)

    Scholes, F. H.; Soste, C.; Hughes, A. E.; Hardin, S. G.; Curtis, P. R.

    2006-12-01

    Cerium-based conversion coatings are progressing as an effective alternative to hazardous chromate-based systems used in the treatment of metal surfaces. However, there is still considerable debate over the mechanism by which these coatings are formed. Here, titrations of cerium-based conversion coating solutions were carried out in order to model the reactions that occur at the metal-solution interface during coating, with a particular emphasis on investigating the role of hydrogen peroxide (H 2O 2). The titration curves obtained support the proposed formation of Ce(III) peroxo complexes such as Ce(H 2O 2) 3+ as an initial step, followed by deprotonation, oxidation and precipitation to form peroxo-containing Ce(IV) species such as Ce (IV)(O 2)(OH) 2. The precipitates resulting from titrations were characterised by Raman spectroscopy, X-ray diffraction and thermogravimetric analysis, confirming the presence of peroxo bonds, and nano-sized CeO 2 crystallites that decreased in size with increasing H 2O 2 concentration. Characterisation of cerium conversion coatings on aluminium alloy surfaces confirmed the presence of peroxo species in the coatings, thereby supporting the titration model.

  10. Aqueous Co-precipitation of Pd-doped Cerium Oxide Nanoparticles: Chemistry Structure and Particle Growth

    SciTech Connect

    Liang H.; Zhang L.; Raitano J.M.; He G.; Akey A.J.; Herman I.P.; Chan S.-W.

    2012-01-01

    Nanoparticles of palladium-doped cerium oxide (Pd-CeO{sub 2}) have been prepared by aqueous co-precipitation resulting in a single phase cubic structure after calcination according to X-ray diffraction (XRD). Inhomogeneous strain, calculated using the Williamson-Hall method, was found to increase with palladium content, and the lattice contracts slightly, relative to nano-cerium oxide, as palladium content is increased. Moreover, high resolution transmission electron microscopy reveals some instances of defective microstructure. These factors combined imply that palladium is in solid solution with CeO{sub 2} in these nanoparticles, but palladium (II) oxide (PdO) peaks in the Raman spectra indicate that solid solution formation is partial and that highly dispersed PdO is present as well as the solid solution. Nevertheless, the addition of palladium to the CeO{sub 2} lattice inhibits the growth of the 6% Pd-CeO{sub 2} particles compared to pure CeO{sub 2} between 600 and 850 C. Activation energies for grain growth of 54 {+-} 7 and 79 {+-} 8 kJ/mol were determined for 6% Pd-CeO{sub 2} and pure CeO{sub 2}, respectively, along with pre-exponential Arrhenius factors of 10 for the doped sample and 600 for pure cerium oxide.

  11. Cerium, gallium and zinc containing mesoporous bioactive glass coating deposited on titanium alloy

    NASA Astrophysics Data System (ADS)

    Shruti, S.; Andreatta, F.; Furlani, E.; Marin, E.; Maschio, S.; Fedrizzi, L.

    2016-08-01

    Surface modification is one of the methods for improving the performance of medical implants in biological environment. In this study, cerium, gallium and zinc substituted 80%SiO2-15%CaO-5%P2O5 mesoporous bioactive glass (MBG) in combination with polycaprolactone (PCL) were coated over Ti6Al4 V substrates by dip-coating method in order to obtain an inorganic-organic hybrid coating (MBG-PCL). Structural characterization was performed using XRD, nitrogen adsorption, SEM-EDXS, FTIR. The MBG-PCL coating uniformly covered the substrate with the thickness found to be more than 1 μm. Glass and polymer phases were detected in the coating along with the presence of biologically potent elements cerium, gallium and zinc. In addition, in vitro bioactivity was investigated by soaking the coated samples in simulated body fluid (SBF) for up to 30 days at 37 °C. The apatite-like layer was monitored by FTIR, SEM-EDXS and ICP measurements and it formed in all the samples within 15 days except zinc samples. In this way, an attempt was made to develop a new biomaterial with improved in vitro bioactive response due to bioactive glass coating and good mechanical strength of Ti6Al4 V alloy along with inherent biological properties of cerium, gallium and zinc.

  12. Controlled Redox Chemistry at Cerium within a Tripodal Nitroxide Ligand Framework.

    PubMed

    Bogart, Justin A; Lippincott, Connor A; Carroll, Patrick J; Booth, Corwin H; Schelter, Eric J

    2015-12-01

    Ligand reorganization has been shown to have a profound effect on the outcome of cerium redox chemistry. Through the use of a tethered, tripodal, trianionic nitroxide ligand, [((2-tBuNOH)C6 H4 CH2 )3 N](3-) (TriNOx (3-) ), controlled redox chemistry at cerium was accomplished, and typically reactive complexes of tetravalent cerium were isolated. These included rare cationic complexes [Ce(TriNOx )thf][BAr(F) 4 ], in which Ar(F) =3,5-(CF3 )2 -C6 H3 , and [Ce(TriNOx )py][OTf]. A rare complete Ce-halide series, Ce(TriNOx )X, in which X=F(-) , Cl(-) , Br(-) , I(-) , was also synthesized. The solution chemistry of these complexes was explored through detailed solution-phase electrochemistry and (1) H NMR experiments and showed a unique shift in the ratio of species with inner- and outer-sphere anions with size of the anionic X(-) group. DFT calculations on the series of calculations corroborated the experimental findings.

  13. Microstructure and electrochemical behavior of cerium conversion coating modified with silane agent on magnesium substrates

    NASA Astrophysics Data System (ADS)

    Lei, Li; Shi, Jing; Wang, Xin; Liu, Dan; Xu, Haigang

    2016-07-01

    The cerium conversion coating with and without different concentrations of silane agent bis-(γ-triethoxysilylpropyl)-tetrasulfide (BTESPT) modification is obtained on magnesium alloys. Detailed properties of the coatings and the role of BTESPT as an additive are studied and followed with careful discussion. The coating morphology, wettability, chemical composition and corrosion resistance are characterized by scanning electronic microscope (SEM), water contact-angle, X-ray photoelectron spectroscopy (XPS), potentiodynamic measurements and electrochemical impedance spectroscopy (EIS). The electrochemical behavior of the coatings is investigated using EIS. The results indicate that the coating morphology and composition can be controlled by changing silane concentration. The combination of cerium ions and silane molecules could promote the formation of more homogenous and higher hydrophobic coating. The coating turns to be more compact and the adhesive strength between the coating and the magnesium substrate are strongly improved with the formation of Sisbnd Osbnd Si and Sisbnd Osbnd M chemical bonds. The optimum corrosion resistance of the coating in the corrosive media is obtained by 25 ml L-1 BTESPT modification. This whole study implies that the cerium conversion coating modified with certain silane agent deserves cautiousness before its application for corrosion resistance.

  14. Preclinical development of AMG 139, a human antibody specifically targeting IL-23

    PubMed Central

    Köck, K; Pan, W J; Gow, J M; Horner, M J; Gibbs, J P; Colbert, A; Goletz, T J; Newhall, K J; Rees, W A; Sun, Y; Zhang, Y; O'Neill, J C; Umble-Romero, A N; Prokop, S P; Krill, C D; Som, L; Buntich, S A; Trimble, M W; Tsuji, W H; Towne, J E

    2015-01-01

    BACKGROUND AND PURPOSE AMG 139 is a human anti-IL-23 antibody currently in a phase II trial for treating Crohn's disease. To support its clinical development in humans, in vitro assays and in vivo studies were conducted in cynomolgus monkeys to determine the pharmacology, preclinical characteristics and safety of this monoclonal antibody. EXPERIMENTAL APPROACH The in vitro pharmacology, pharmacokinetics (PK), pharmacodynamics and toxicology of AMG 139, after single or weekly i.v. or s.c. administration for up to 26 weeks, were evaluated in cynomolgus monkeys. KEY RESULTS AMG 139 bound with high affinity to both human and cynomolgus monkey IL-23 and specifically neutralized the biological activity of IL-23 without binding or blocking IL-12. After a single dose, linear PK with s.c. bioavailability of 81% and mean half-life of 8.4–13 days were observed. After weekly s.c. dosing for 3 or 6 months, AMG 139 exposure increased approximately dose-proportionally from 30 to 300 mg·kg−1 and mean accumulation between the first and last dose ranged from 2- to 3.5-fold. Peripheral blood immunophenotyping, T-cell-dependent antigen responses and bone formation markers were not different between AMG 139 and vehicle treatment. No adverse clinical signs, effects on body weight, vital signs, ophthalmic parameters, clinical pathology, ECG, organ weights or histopathology were observed in the monkeys with the highest dose of AMG 139 tested (300 mg·kg−1 s.c. or i.v.). CONCLUSIONS AND IMPLICATIONS The in vitro pharmacology, PK, immunogenicity and safety characteristics of AMG 139 in cynomolgus monkeys support its continued clinical development for the treatment of various inflammatory diseases. PMID:25205227

  15. miR-139 modulates MCPIP1/IL-6 expression and induces apoptosis in human OA chondrocytes

    PubMed Central

    Makki, Mohammad Shahidul; Haqqi, Tariq M

    2015-01-01

    IL-6 is an inflammatory cytokine and its overexpression plays an important role in osteoarthritis (OA) pathogenesis. Expression of IL-6 is regulated post-transcriptionally by MCPIP1. The 3′ untranslated region (UTR) of MCPIP1 mRNA harbors a miR-139 ‘seed sequence', therefore we examined the post-transcriptional regulation of MCPIP1 by miR-139 and its impact on IL-6 expression in OA chondrocytes. Expression of miR-139 was found to be high in the damaged portion of the OA cartilage compared with unaffected cartilage from the same patient and was also induced by IL-1β in OA chondrocytes. Inhibition of miR-139 decreased the expression of IL-6 mRNA by 38% and of secreted IL-6 protein by 40%. However, overexpression of miR-139 increased the expression of IL-6 mRNA by 36% and of secreted IL-6 protein by 56%. These data correlated with altered expression profile of MCPIP1 in transfected chondrocytes. Studies with a luciferase reporter construct confirmed the interactions of miR-139 with the ‘seed sequence' located in the 3′ UTR of MCPIP mRNA. Furthermore, miR-139 overexpression increased the catabolic gene expression but expression of anabolic markers remained unchanged. Overexpression of miR-139 also induced apoptosis in OA chondrocytes. Importantly, we also discovered that IL-6 is a potent inducer of miR-139 expression in OA chondrocytes. These findings indicate that miR-139 functions as a post-transcriptional regulator of MCPIP1 expression and enhances IL-6 expression, which further upregulates miR-139 expression in OA chondrocytes. These results support our hypothesis that miR-139-mediated downregulation of MCPIP1 promotes IL-6 expression in OA. Therefore, targeting miR-139 could be therapeutically beneficial in the management of OA. PMID:26450708

  16. Grain Growth Behavior, Tensile Impact Ductility, and Weldability of Cerium-Doped Iridium Alloys

    SciTech Connect

    McKamey, C.G.

    2002-05-28

    An iridium alloy doped with small amounts of cerium and thorium is being developed as a potential replacement for the iridium-based DOP-26 alloy (doped with thorium only) that is currently used by the National Aeronautics and Space Administration (NASA) for cladding and post-impact containment of the radioactive fuel in radioisotope thermoelectric generator (RTG) heat sources which provide electric power for interplanetary spacecraft. This report summarizes results of studies conducted to date under the Iridium Alloy Characterization and Development subtask of the Radioisotope Power System Materials Production and Technology Program to characterize the properties of the iridium-based alloy (designated as DOP-40) containing both cerium and thorium. Included within this report are data on grain growth of sheet material in vacuum and low-pressure oxygen environments, grain growth in vacuum of the clad vent set cup material, weldability, and the effect of grain size and test temperature on tensile properties. Where applicable, data for the DOP-26 alloy are included for comparison. Both grain size and grain-boundary cohesion affect the ductility of iridium alloys. In this study it was found that cerium and thorium, when added together, refine grain size more effectively than when thorium is added by itself (especially at high temperatures). In addition, the effect of cerium additions on grain-boundary cohesion is similar to that of thorium. Mechanical testing at both low ({approx} 10{sup -3}s{sup -1}) and high ({approx} 10{sup -3}s{sup -1}) strain rates showed that the Ce/Th-doped alloys have tensile ductilities that are as good or better than the DOP-26 alloy. The general conclusion from these studies is that cerium can be used to replace some of the radioactive thorium currently used in DOP-26 while maintaining or improving its metallurgical properties. The current DOP-26 alloy meets all requirements for cladding the radioactive fuel in the RTG heat source, but the

  17. Using cerium anomaly as an indicator of redox reactions in constructed wetland

    NASA Astrophysics Data System (ADS)

    Liang, R.

    2013-12-01

    dissolved oxygen (5 ppm) but the NH4 content is still high, which indicates a non-equilibrium condition. In this study, the cerium anomaly is alternatively utilized to evaluate the water redox state. The results demonstrate that the input water has the negative cerium anomaly of -0.16. Along the flow path, the cerium negative anomaly does not change in the first two cells and dramatically becomes -0.23 in cell 3. The trend of cerium anomaly is more close to the removal efficiency of NH4 rather than dissolve oxygen. Accordingly, cerium anomaly could become a better indicator of removal efficiency of constructed wetland.

  18. Self-poled transparent and flexible UV light-emitting cerium complex-PVDF composite: a high-performance nanogenerator.

    PubMed

    Garain, Samiran; Sinha, Tridib Kumar; Adhikary, Prakriti; Henkel, Karsten; Sen, Shrabanee; Ram, Shanker; Sinha, Chittaranjan; Schmeißer, Dieter; Mandal, Dipankar

    2015-01-21

    Cerium(III)-N,N-dimethylformamide-bisulfate [Ce(DMF)(HSO4)3] complex is doped into poly(vinylidene fluoride) (PVDF) to induce a higher yield (99%) of the electroactive phases (β- and γ-phases) of PVDF. A remarkable enhancement of the output voltage (∼32 V) of a nanogenerator (NG) based on a nonelectrically poled cerium(III) complex containing PVDF composite film is achieved by simple repeated human finger imparting, whereas neat PVDF does not show this kind of behavior. This high electrical output resembles the generation of self-poled electroactive β-phase in PVDF due to the electrostatic interactions between the fluoride of PVDF and the surface-active positive charge cloud of the cerium complex via H-bonding and/or bipolar interaction among the opposite poles of cerium complex and PVDF, respectively. The capacitor charging capability of the flexible NG promises its applicability as piezoelectric-based energy harvester. The cerium(III) complex doped PVDF composite film exhibit an intense photoluminescence in the UV region, which might be due to a participation of electron cloud from negative pole of bipolarized PVDF. This fact may open a new area for prospective development of high-performance energy-saving flexible solid-state UV light emitters. PMID:25523039

  19. Cyanex 923 as the extractant in a rare earth element impurity analysis of high-purity cerium oxide.

    PubMed

    Duan, Taicheng; Li, Hongfei; Kang, JianZhen; Chen, Hangting

    2004-06-01

    In this work, the feasibility of employing Cyanex 923 as an extractant into the non-cerium REE (rare earth elements) impurity analysis of high-purity cerium oxide was investigated. Through investigations on the choice of the extraction medium, the optimium extraction acidity, matrix Ce4+ effect on the non-cerium REE ion extraction, the optimium extractant concentration and suitable extracting time, and oscillation strengh, it was found that when the phase ratio was at 1:1 and the acicidity was about 2% H2SO4, by gently shaking by hand for about 2 min, 10 mL of 30% Cyanex 923 could not extract even for a 20 ng amount of non-cerium REE3+ ions. However, the extraction efficiency for Ce4+ of 100 mg total amount under the same conditions was about 96%, indicating that a 25-fold preconcentration factor could be achieved. Thus, it was concluded that Cyanex 923 could be used in a REE impurity analysis of 99.9999% or so pure cerium oxide for primary sepapation to elimilate matrix-induced interferences encountered in an ICP-MS (inductively coupled plasma mass spectroscopy) determination.

  20. Molecular epidemiology of O139 Vibrio cholerae: mutation, lateral gene transfer, and founder flush.

    PubMed

    Garg, Pallavi; Aydanian, Antonia; Smith, David; J Glenn, Morris; Nair, G Balakrish; Stine, O Colin

    2003-07-01

    Vibrio cholerae in O-group 139 was first isolated in 1992 and by 1993 had been found throughout the Indian subcontinent. This epidemic expansion probably resulted from a single source after a lateral gene transfer (LGT) event that changed the serotype of an epidemic V. cholerae O1 El Tor strain to O139. However, some studies found substantial genetic diversity, perhaps caused by multiple origins. To further explore the relatedness of O139 strains, we analyzed nine sequenced loci from 96 isolates from patients at the Infectious Diseases Hospital, Calcutta, from 1992 to 2000. We found 64 novel alleles distributed among 51 sequence types. LGT events produced three times the number of nucleotide changes compared to mutation. In contrast to the traditional concept of epidemic spread of a homogeneous clone, the establishment of variant alleles generated by LGT during the rapid expansion of a clonal bacterial population may be a paradigm in infections and epidemics. PMID:12890320