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1

Zirconium isotope separation  

SciTech Connect

A method of separating zirconium isotopes by converting the zirconium to its iodide salt prior to separation by usual isotope methods is disclosed. After separation the desired isotopes are converted from the salt to the metal by the van Arkel-de Boer iodide process.

Siddall, M.B.

1984-12-11

2

Zirconium in sulfuric acid applications  

SciTech Connect

Zirconium is one of the few metals that resists attack by sulfuric acid at concentrations up to 75% and temperatures to boiling and above. This capability makes zirconium a good structural metal for use in 40 to 65% H/sub 2/SO/sub 4/ up to boiling temperatures and for weak acid concentrations at elevated temperatures. Zirconium's corrosion properties in sulfuric acid solutions are compared with nickel base alloys. Examples of applications and limitations in the use of zirconium are presented.

Webster, R.T.; Yau, T.L.

1986-02-01

3

Creep and creep fracture of zirconium and zirconium alloys  

NASA Astrophysics Data System (ADS)

The creep and creep failure mechanisms for zirconium and zirconium alloys have not been established, yet these properties are required to establish safe conditions for the interim dry storage of spent nuclear fuel. The purpose of this research, then, is to determine the relevant creep and creep fracture mechanisms controlling the deformation and failure of zirconium and zirconium alloys at elevated temperatures. Currently, the maximum allowable temperatures for the storage of spent nuclear fuel are defined by the Nuclear Regulatory Commission based on a limited set of experimental data. Recent changes in regulations will be evaluated and recommendations made regarding their applicability. Various studies in the past have reported that zirconium and zirconium alloys exhibit anomalous creep properties. A detailed analysis of the creep properties of zirconium and zirconium alloys is presented based on an extensive literature review. Next, developments in creep fracture phenomena in engineering materials over the past several decades will be discussed and related to the creep fracture of zirconium alloys. As will be discussed, the mechanism for plasticity can be intimately tied to the fracture mechanism. The results of uniaxial creep tests on zirconium at temperatures of 350--700°C and stresses of 8--70 MPa and uniaxial creep tests on Zircaloy-2 at temperatures of 300--600°C and stresses of 24--382 MPa and subsequent microstructural investigation using a scanning electron microscope will be discussed, particularly as relevant to the fracture mechanisms for this alloy.

Hayes, Troy Allyn

4

Electroless deposition process for zirconium and zirconium alloys  

DOEpatents

A method is disclosed for preventing stress corrosion cracking or metal embrittlement of a zirconium or zirconium alloy container that is to be coated on the inside surface with a layer of a metal such as copper, a copper alloy, nickel, or iron and used for holding nuclear fuel material as a nuclear fuel element. The zirconium material is etched in an etchant solution, desmutted mechanically or ultrasonically, oxidized to form an oxide coating on the zirconium, cleaned in an aqueous alkaline cleaning solution, activated for electroless deposition of a metal layer and contacted with an electroless metal plating solution. This method provides a boundary layer of zirconium oxide between the zirconium container and the metal layer.

Donaghy, Robert E. (Wilmington, NC); Sherman, Anna H. (Wilmington, NC)

1981-01-01

5

Electroless deposition process for zirconium and zirconium alloys  

DOEpatents

A method is disclosed for preventing stress corrosion cracking or metal embrittlement of a zirconium or zirconium alloy container that is to be coated on the inside surface with a layer of a metal such as copper, a copper alloy, nickel, or iron and used for holding nuclear fuel material as a nuclear fuel element. The zirconium material is etched in an etchant solution, desmutted mechanically or ultrasonically, oxidized to form an oxide coating on the zirconium, cleaned in an aqueous alkaline cleaning solution, activated for electroless deposition of a metal layer and contacted with an electroless metal plating solution. This method provides a boundary layer of zirconium oxide between the zirconium container and the metal layer. 1 fig.

Donaghy, R. E.; Sherman, A. H.

1981-08-18

6

ZIRCONIUM AND HAFNIUM--1999 86.1 ZIRCONIUM AND HAFNIUM  

E-print Network

cladding, chemical piping in corrosive environments, heat exchangers, and various specialty alloys.I. du Pont de Nemours and Co. (DuPont). DuPont produced zircon from its Highland and Maxville heavy, and Western Zirconium, a subsidiary of Westinghouse Electric Company, Ogden, UT. Primary zirconium chemicals

7

Process for purifying zirconium sponge  

SciTech Connect

This patent describes a Kroll reduction process wherein a zirconium sponge contaminated with unreacted magnesium and by-product magnesium chloride is produced as a regulus, a process for purifying the zirconium sponge. It comprises: distilling magnesium and magnesium chloride from: a regulus containing a zirconium sponge and magnesium and magnesium chloride at a temperature above about 800{degrees} C and at an absolute pressure less than about 10 mmHg in a distillation vessel to purify the zirconium sponge; condensing the magnesium and the magnesium chloride distilled from the zirconium sponge in a condenser; and then backfilling the vessel containing the zirconium sponge and the condenser containing the magnesium and the magnesium chloride with a gas; recirculating the gas between the vessel and the condenser to cool the zirconium sponge from above about 800{degrees} C to below about 300{degrees} C; and cooling the recirculating gas in the condenser containing the condensed magnesium and the condensed magnesium chloride as the gas cools the zirconium sponge to below about 300{degrees} C.

Abodishish, H.A.M.; Kimball, L.S.

1992-03-31

8

ZIRCONIUM AND HAFNIUM By Joseph Gambogi  

E-print Network

1 ZIRCONIUM AND HAFNIUM By Joseph Gambogi Zirconium and hafnium are relatively abundant of commercial significance. Zirconium and containing alloys. hafnium are both contained in zircon at a ratio for zirconium and hafnium materials are developed by hafnium and is used in the chemical process industries

9

Zirconium-containing coating composition  

SciTech Connect

This patent describes a binderless coating composition, free from alkaline and alkaline earth metallic oxides, hafnium, silica, and alumina, comprising substantially pure zirconium oxide suspended in an aqueous zirconyl nitrate and ammonium hydroxide gel.

Peterson, J.R.

1992-05-19

10

Organic derivatives of zirconium phosphate  

E-print Network

ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1980 Major Subject...: Chemistry ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Approved as to style and content by: Dr. A raham Clearfield (c irman) Dr. Kurt Irgolic (member) 4~~@4 Dr. Martha Scott (member) Dr. C. S. Giam (department head...

Fine, Steven Beryl

2012-06-07

11

Nanolithography on Zirconium Surfaces  

NASA Astrophysics Data System (ADS)

We report, for the first time, scanning probe nanolithography on single crystal zirconium (Zr) surfaces using an atomic force microscope (AFM) tip in air. Preliminary experiments indicate that the size of the nanostructures written on Zr is 50 - 100 nm with applied DC voltages of 1 - 25 V and exposure times in the range of 1 - 60 seconds. We study the dependence of the size of the nanostructures on the magnitude of the applied voltage and current through the Zr substrate. This allows us to compare the results of SPM lithography on Zr with those on Si. Apparently, the nature of the current in these two cases is different. The current during high voltage Si oxidation exhibits Ohmic behavior and can reach 300 microamps. We believe that this current is the result of electrical breakdown in the meniscus of water resulting in conductivity dominated by electron mobility. In the case of Zr, the magnitude of the DC current is very small (less than 1 microamp) and exhibits typical Faradic behavior related with the transport of hydroxyl ions from an AFM tip down to the Zr surface. Lithographic oxidation of Zr surfaces is a very promising step toward the development of a comprehensive description of the nanolithographic process and complements our efforts to prepare Zr surfaces with novel properties via hyperthermal chemical reaction pathways.

Farkas, Natalia; Lyuksyutov, Sergei F.; Ramsier, Rex D.

2002-04-01

12

Transformation superplasticity of zirconium  

NASA Astrophysics Data System (ADS)

A tensile strain of 270 pct was achieved for coarse-grained zirconium subjected to transformation superplasticity conditions, where strain increments are accumulated upon repeated thermal cycling around the allotropic transformation temperature under the biasing effect of a uniaxial tensile stress. The strain increment per cycle was found to consist of two equal contributions from transformations on heating and cooling and to increase linearly with the applied stress. The measured strain increments are in good quantitative agreement with predictions based on the average internal stress during the transformation, which was determined independently from experimental transformation times. As the cycling frequency is raised, the average strain rate increases (a maximum value of 1.3·10-4 s-1 was measured), but the strain increment per cycle decreases above a critical cycling frequency, for which the sample gage section undergoes only a partial phase transformation. The resulting reduction in internal mismatch and increase in internal stress are modeled using the experimental observation that ?-Zr deforms by a mixture of diffusional and dislocation creep in the stress range of interest.

Zwigl, Peter; Dunand, David C.

1998-10-01

13

Mesostructured zirconium oxide  

SciTech Connect

The supramolecular templating technique was used to synthesize both hexagonal (Hx-ZrO{sub 2}) and lamellar (L-ZrO{sub 2}) phases of zirconium oxide. Under the conditions used in this work, the use of long chain primary amines and quaternary ammonium surfactants resulted in the exclusive formation of lamellar and hexagonal phases, respectively. The use of long chain cetyldimethylamine afforded a mixture of a hexagonal and a lamellar phase. Effects of synthesis parameters such as the ZrO{sub 2}/surfactant ratio, ZrO{sub 2}/water ratio, the nature of surfactant, the crystallization temperature and time on the formation of mesostructured ZrO{sub 2} were also studied. Addition of 1,3,5-trimethylbenzene (TMB) as a swelling agent led, in the presence of cetyltrimethylammonium bromide, to the formation of a lamellar phase rather than to pore enlargement. These materials were characterized by XRD, FTIR, XPS and EDX techniques. Regardless of their structure, the as-synthesized materials collapsed upon calcination. Treatment with monobasic potassium phosphate followed by calcination at 350 C led to the formation of a stable porous Zr-P oxide with a surface area as high as 540 m{sup 2}/g.

Liu, P.; Reddy, J.S.; Adnot, A.; Sayari, A. [Univ. Laval, Ste-Foy, Quebec (Canada)

1996-12-31

14

Ablation Resistant Zirconium and Hafnium Ceramics  

NASA Technical Reports Server (NTRS)

High temperature ablation resistant ceramic composites have been made. These ceramics are composites of zirconium diboride and zirconium carbide with silicon carbide, hafnium diboride and hafnium carbide with silicon carbide and ceramic composites which contain mixed diborides and/or carbides of zirconium and hafnium. along with silicon carbide.

Bull, Jeffrey (Inventor); White, Michael J. (Inventor); Kaufman, Larry (Inventor)

1998-01-01

15

ZIRCONIUM AND HAFNIUM By Joseph M. Gambogi  

E-print Network

1 ZIRCONIUM AND HAFNIUM By Joseph M. Gambogi Zirconium and hafnium are relatively Australia and hafnium are both contained in 1995. zircon at a ratio of about 50 to 1. Zircon is a byproduct. Production Data for zirconium and hafnium materials are developed by the U.S. Bureau of Mines from one

16

Zirconium and hafnium in meteorites  

NASA Technical Reports Server (NTRS)

The abundances of zirconium and hafnium have been determined in nine stony meteorites by a new, precise neutron-activation technique. The Zr/Hf abundance ratios for the chondrites vary in a rather narrow range, consistent with previously published observations from our group. Replicate analyses of new, carefully selected clean interior samples of the Cl chondrite Orgueil yield mean zirconium and hafnium abundances of 5.2 and 0.10 ppm, respectively. These abundances are lower than we reported earlier for two Cl chondrite samples which we now suspect may have suffered contamination. The new Cl zirconium and hafnium abundances are in closer agreement with predictions based on theories of nucleosynthesis than the earlier data.

Ehmann, W. D.; Chyi, L. L.

1974-01-01

17

ZIRCONIUM AND HAFNIUM--2001 86.1 ZIRCONIUM AND HAFNIUM  

E-print Network

, Inc. (a subsidiary of the Australian company Iluka Resources Ltd.). DuPont produced zircon from its and Magnesium Elektron Inc., Flemington, NJ. Secondary zirconium chemicals were produced by about 10 companies in nuclear fuel cladding, chemical processing equipment (pipes, valves, pumps), heat exchangers

18

40 CFR 721.10602 - Lead niobium titanium zirconium oxide.  

...2014-07-01 false Lead niobium titanium zirconium oxide. 721.10602 Section...Substances § 721.10602 Lead niobium titanium zirconium oxide. (a) Chemical substance...chemical substance identified as lead niobium titanium zirconium oxide (PMN...

2014-07-01

19

40 CFR 721.10598 - Lead strontium titanium zirconium oxide.  

...2014-07-01 false Lead strontium titanium zirconium oxide. 721.10598 Section...Substances § 721.10598 Lead strontium titanium zirconium oxide. (a) Chemical substance...substance identified as lead strontium titanium zirconium oxide (PMN...

2014-07-01

20

40 CFR 721.10601 - Lanthanum lead titanium zirconium oxide.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Lanthanum lead titanium zirconium oxide. 721.10601 Section...Substances § 721.10601 Lanthanum lead titanium zirconium oxide. (a) Chemical substance...substance identified as lanthanum lead titanium zirconium oxide (PMN...

2013-07-01

21

40 CFR 721.10598 - Lead strontium titanium zirconium oxide.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Lead strontium titanium zirconium oxide. 721.10598 Section...Substances § 721.10598 Lead strontium titanium zirconium oxide. (a) Chemical substance...substance identified as lead strontium titanium zirconium oxide (PMN...

2013-07-01

22

40 CFR 721.10601 - Lanthanum lead titanium zirconium oxide.  

...2014-07-01 false Lanthanum lead titanium zirconium oxide. 721.10601 Section...Substances § 721.10601 Lanthanum lead titanium zirconium oxide. (a) Chemical substance...substance identified as lanthanum lead titanium zirconium oxide (PMN...

2014-07-01

23

40 CFR 721.10602 - Lead niobium titanium zirconium oxide.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Lead niobium titanium zirconium oxide. 721.10602 Section...Substances § 721.10602 Lead niobium titanium zirconium oxide. (a) Chemical substance...chemical substance identified as lead niobium titanium zirconium oxide (PMN...

2013-07-01

24

Applications for zirconium and columbium alloys  

SciTech Connect

Currently, zirconium and columbium are used in a wide range of applications, overlapping only in the field of corrosion control. As a construction material, zirconium is primarily used by the nuclear power industry. The use of zirconium in the chemical processing industry (CPI) is, however, increasing steadily. Columbian alloys are primarily applied as superconducting alloys for research particle accelerators and fusion generators as well as in magnetic resonance imaging for medical diagnosis.

Condliff, A.F.

1986-09-01

25

2006 Minerals Yearbook ZIRCONIUM AND HAFNIUM  

E-print Network

subsidiary of Australian company Iluka Resources Ltd.). DuPont produced zircon from its heavy- mineral sands from intermediate zirconium chemicals, were produced by about 10 companies. Zirconia was produced from withheld to avoid disclosing company proprietary data. Domestic production of milled zircon and zirconium

26

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use to begin operating in Georgia in 2004. Zirconium and hafnium metal were produced from zircon sand by two in a zirconium to hafnium ratio of about 50:1. Primary zirconium chemicals were produced by the Oregon metal

27

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use that will be trucked to a dry mill in Florida for separation. Zirconium and hafnium metals were produced from zircon are in the ore in a zirconium to hafnium ratio of about 50:1. Primary zirconium chemicals were produced

28

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

192 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida and at one mine in Virginia. Zirconium and hafnium metal. Typically, both metals are in the ore in a zirconium to hafnium ratio of about 50:1. Primary zirconium

29

Method of making crack-free zirconium hydride  

DOEpatents

Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

Sullivan, Richard W. (Denver, CO)

1980-01-01

30

Penta­zirconium copper tribismuth  

PubMed Central

Penta­zirconium copper tribismuth, Zr5CuBi3, crystallizes in the hexa­gonal Hf5CuSn3 structure type. The asymmetric unit contains two Zr sites (site symmetries 3.2 and m2m), one Cu site (site symmetry 3.m) and one Bi site (site symmetry m2m). The environment of the Bi atoms is a tetra­gonal anti­prism with one added atom and a coordination number (CN) of 9. The polyhedron around the Zr1 atom is a defective cubo­octa­hedron with CN = 11. The bicapped hexa­gonal anti­prism (CN = 14) is typical for Zr2 atoms. The Cu atom is enclosed in a eight-vertex polyhedron (octa­hedron with two centered faces). The metallic type of bonding was indicated by an analysis of the inter­atomic distances and electronic structure calculation data. PMID:24109256

Balinska, Agnieszka; Tarasiuk, Ivan; Pavlyuk, Volodymyr

2013-01-01

31

Penta-zirconium copper tribismuth.  

PubMed

Penta-zirconium copper tribismuth, Zr5CuBi3, crystallizes in the hexa-gonal Hf5CuSn3 structure type. The asymmetric unit contains two Zr sites (site symmetries 3.2 and m2m), one Cu site (site symmetry 3.m) and one Bi site (site symmetry m2m). The environment of the Bi atoms is a tetra-gonal anti-prism with one added atom and a coordination number (CN) of 9. The polyhedron around the Zr1 atom is a defective cubo-octa-hedron with CN = 11. The bicapped hexa-gonal anti-prism (CN = 14) is typical for Zr2 atoms. The Cu atom is enclosed in a eight-vertex polyhedron (octa-hedron with two centered faces). The metallic type of bonding was indicated by an analysis of the inter-atomic distances and electronic structure calculation data. PMID:24109256

Balinska, Agnieszka; Tarasiuk, Ivan; Pavlyuk, Volodymyr

2013-01-01

32

ZIRCONIUM OXIDE NANOSTRUCTURES PREPARED BY ANODIC OXIDATION  

SciTech Connect

Zirconium oxide is an advanced ceramic material highly useful for structural and electrical applications because of its high strength, fracture toughness, chemical and thermal stability, and biocompatibility. If highly-ordered porous zirconium oxide membranes can be successfully formed, this will expand its real-world applications, such as further enhancing solid-oxide fuel cell technology. Recent studies have achieved various morphologies of porous zirconium oxide via anodization, but they have yet to create a porous layer where nanoholes are formed in a highly ordered array. In this study, electrochemical methods were used for zirconium oxide synthesis due to its advantages over other coating techniques, and because the thickness and morphology of the ceramic fi lms can be easily tuned by the electrochemical parameters, such as electrolyte solutions and processing conditions, such as pH, voltage, and duration. The effects of additional steps such as pre-annealing and post-annealing were also examined. Results demonstrate the formation of anodic porous zirconium oxide with diverse morphologies, such as sponge-like layers, porous arrays with nanoholes ranging from 40 to 75 nm, and nanotube layers. X-ray powder diffraction analysis indicates a cubic crystallographic structure in the zirconium oxide. It was noted that increased voltage improved the ability of the membrane to stay adhered to the zirconium substrate, whereas lower voltages caused a propensity for the oxide fi lm to fl ake off. Further studies are needed to defi ne the parameters windows that create these morphologies and to investigate other important characteristics such as ionic conductivity.

Dang, Y. Y.; Bhuiyan, M.S.; Paranthaman, M. P.

2008-01-01

33

Microstructural evolution in zirconium based alloys  

NASA Astrophysics Data System (ADS)

Zirconium alloys which exhibit practically all possible solid state phase transformations offer some unique opportunities for studying the fundamental aspects of phase transformations. The crystallographic features associated with the phase changes are much simpler in zirconium based systems, making them more suitable for providing a basic understanding of the relevant phenomena. Some of the important issues related to phase transformations research are identified and the manner, in which studies in zirconium alloys have contributed to the understanding of these issues, is discussed in this paper. Both the types of displacive transformations - shear-dominated and shuffle dominated - are encountered in zirconium alloys. The crystallography and the mechanism of such transformations are discussed, giving special reference to the morphological and sub-structural changes in zirconium martensites and to the fine particle and plate-shaped morphologies of the ?-phase. Morphological and crystallographical features of displacive and diffusional transformations have been compared. Several examples of mixed mode transformations, viz., the formation of ?-hydride phase, the active eutectoid decomposition and the formation of ordered ?-phases are cited and their respective mechanisms described.

Tewari, R.; Srivastava, D.; Dey, G. K.; Chakravarty, J. K.; Banerjee, S.

2008-12-01

34

2005 Minerals Yearbook ZirconiuM and HafniuM  

E-print Network

nemours & co. (duPont)] and iluka resources, inc. (a subsidiary of australian company iluka resources Ltd zirconium chemicals, produced from intermediate zirconium chemicals, were produced by about 10 companies disclosing company proprietary data. domestic production of milled zircon was unchanged and of zirconium

35

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

188 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use minerals. Typically, zirconium and hafnium are contained in zircon at a ratio of about 50 to 1. Two firms produced zircon from surface-mining operations in Florida and Virginia. Zirconium metal and hafnium metal

36

Atomic Layer Deposition of Insulating Hafnium and Zirconium Nitrides  

E-print Network

Atomic Layer Deposition of Insulating Hafnium and Zirconium Nitrides Jill S. Becker, Esther Kim, and conformal coatings of higher nitrides of hafnium and zirconium were produced by atomic layer deposition from-colored, and highly conducting. I. Introduction The mononitrides of hafnium and zirconium of stoi- chiometry MN (M

37

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

192 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use. Zirconium and hafnium elements were produced from zircon by two domestic producers, one in Oregon and the other in Utah. Typically, both elements are in the ore in a zirconium to hafnium ratio of about 50

38

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

188 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use. Zirconium and hafnium metal were produced from zircon by two domestic producers, one in Oregon and the other in Utah. Typically, both elements occur in the ore in a zirconium-to-hafnium ratio of about 50:1. Primary

39

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

186 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use and hafnium metal were produced from zircon by two domestic producers, one in Oregon and the other in Utah. Typically, both elements are in the ore in a zirconium-to-hafnium ratio of about 50:1. Zirconium chemicals

40

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use minerals. Typically, zirconium and hafnium are contained in zircon at a ratio of about 50 to 1. Two firms produced zircon from surface-mining operations in Florida and Virginia. Zirconium metal and hafnium metal

41

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

192 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use and hafnium metal were produced from zircon by two domestic producers, one in Oregon and the other in Utah. Typically, both elements are in the ore in a zirconium-to-hafnium ratio of about 50:1. Zirconium chemicals

42

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

188 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use and hafnium metal were produced from zircon by two domestic producers, one in Oregon and the other in Utah. Typically, both elements are in the ore in a zirconium-to-hafnium ratio of about 50:1. Zirconium chemicals

43

ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted) Domestic Production and Use minerals. Typically, both elements are in the ore in a zirconium-to-hafnium ratio of about 50:1. Two firms produced zircon from surface-mining operations in Florida and Virginia. Zirconium metal and hafnium metal

44

The chemical vapor deposition of zirconium carbide onto ceramic substrates  

SciTech Connect

Zirconium carbide is an attractive ceramic material due to its unique properties such as high melting point, good thermal conductivity, and chemical resistance. The controlled preparation of zirconium carbide films of superstoichiometric, stoichiometric, and substoichiometric compositions has been achieved utilizing zirconium tetrachloride and methane precursor gases in an atmospheric pressure high temperature chemical vapor deposition system.

Glass, John A, Jr.; Palmisiano, Nick, Jr.; Welsh, R. Edward

1999-07-01

45

Processing fissile material mixtures containing zirconium and/or carbon  

DOEpatents

A method of processing spent TRIZO-coated nuclear fuel may include adding fluoride to complex zirconium present in a dissolved TRIZO-coated fuel. Complexing the zirconium with fluoride may reduce or eliminate the potential for zirconium to interfere with the extraction of uranium and/or transuranics from fission materials in the spent nuclear fuel.

Johnson, Michael Ernest; Maloney, Martin David

2013-07-02

46

ZIRCONIUM AND HAFNIUM (Data in metric tons of zirconium oxide (ZrO ) equivalent, unless otherwise noted)2  

E-print Network

194 ZIRCONIUM AND HAFNIUM (Data in metric tons of zirconium oxide (ZrO ) equivalent, unless in Virginia. Zirconium and hafnium metal were produced from zircon sand by two domestic producers, one each, and sandblasting. The largest market for hafnium metal is an addition in superalloys. Salient Statistics

47

The SHELX-97 Manual 1. General Introduction to SHELX-97  

E-print Network

The SHELX-97 Manual Contents 1. General Introduction to SHELX-97 2. SHELXL: Structure refinement 3 and Disorder 6. Refinement of Twinned Structures; Absolute Structure 7. SHELXL Instruction Summary 8 determinations. A commercial version including interactive reciprocal and real space graphics is available

Meagher, Mary

48

Electrochemical impedance spectroscopic study of passive zirconium  

NASA Astrophysics Data System (ADS)

Spent, unreproccessed nuclear fuel is generally contained within the operational fuel sheathing fabricated from a zirconium alloy (Zircaloy 2, Zircaloy 4, or Zirlo) and is then stored in a swimming pool and/or dry storage facilities until permanent disposal in a licensed repository. During this period, which begins with irradiation of the fuel in the reactor during operation, the fuel sheathing is exposed to various, aggressive environments. The objective of the present study was to characterize the nature of the passive film that forms on pure zirconium in contact with an aqueous phase [0.1 M B(OH) 3 + 0.001 M LiOH, pH 6.94] at elevated temperatures (in this case, 250 °C), prior to storage, using electrochemical impedance spectroscopy (EIS) with the data being interpreted in terms of the point defect model (PDM). The results show that the corrosion resistance of zirconium in high temperature, de-aerated aqueous solutions is dominated by the outer layer. The extracted model parameter values can be used in deterministic models for predicting the accumulation of general corrosion damage to zirconium under a wide range of conditions that might exist in some repositories.

Ai, Jiahe; Chen, Yingzi; Urquidi-Macdonald, Mirna; Macdonald, Digby D.

2008-09-01

49

Sodium Zirconium Cyclosilicate in Hyperkalemia.  

PubMed

Background Hyperkalemia (serum potassium level, >5.0 mmol per liter) is associated with increased mortality among patients with heart failure, chronic kidney disease, or diabetes. We investigated whether sodium zirconium cyclosilicate (ZS-9), a novel selective cation exchanger, could lower serum potassium levels in patients with hyperkalemia. Methods In this multicenter, two-stage, double-blind, phase 3 trial, we randomly assigned 753 patients with hyperkalemia to receive either ZS-9 (at a dose of 1.25 g, 2.5 g, 5 g, or 10 g) or placebo three times daily for 48 hours. Patients with normokalemia (serum potassium level, 3.5 to 4.9 mmol per liter) at 48 hours were randomly assigned to receive either ZS-9 or placebo once daily on days 3 to 14. The primary end point was the exponential rate of change in the mean serum potassium level at 48 hours. Results At 48 hours, the mean serum potassium level had decreased from 5.3 mmol per liter at baseline to 4.9 mmol per liter in the group of patients who received 2.5 g of ZS-9, 4.8 mmol per liter in the 5-g group, and 4.6 mmol per liter in the 10-g group, for mean reductions of 0.5, 0.5, and 0.7 mmol per liter, respectively (P<0.001 for all comparisons) and to 5.1 mmol per liter in the 1.25-g group and the placebo group (mean reduction, 0.3 mmol per liter). In patients who received 5 g of ZS-9 and those who received 10 g of ZS-9, serum potassium levels were maintained at 4.7 mmol per liter and 4.5 mmol per liter, respectively, during days 3 to 15, as compared with a level of more than 5.0 mmol per liter in the placebo group (P<0.01 for all comparisons). Rates of adverse events were similar in the ZS-9 group and the placebo group (12.9% and 10.8%, respectively, in the initial phase; 25.1% and 24.5%, respectively, in the maintenance phase). Diarrhea was the most common complication in the two study groups. Conclusions Patients with hyperkalemia who received ZS-9, as compared with those who received placebo, had a significant reduction in potassium levels at 48 hours, with normokalemia maintained during 12 days of maintenance therapy. (Funded by ZS Pharma; ClinicalTrials.gov number, NCT01737697 .). PMID:25415807

Packham, David K; Rasmussen, Henrik S; Lavin, Philip T; El-Shahawy, Mohamed A; Roger, Simon D; Block, Geoffrey; Qunibi, Wajeh; Pergola, Pablo; Singh, Bhupinder

2014-11-21

50

International strategic minerals inventory summary report; zirconium  

USGS Publications Warehouse

Zircon, a zirconium silicate, is currently the most important commercial zirconium-bearing mineral. Baddeleyite, a natural form of zirconia, is less important but has some specific end uses. Both zircon and baddeleyite occur in hard-rock and placer deposits, but at present all zircon production is from placer deposits. Most baddeleyite production is from hard-rock deposits, principally as a byproduct of copper and phosphate-rock mining. World zirconium resources in identified, economically exploitable deposits are about 46 times current production rates. Of these resources, some 71 percent are in South Africa, Australia, and the United States. The principal end uses of zirconium minerals are in ceramic applications and as refractories, abrasives, and mold linings in foundries. A minor amount, mainly of zircon, is used for the production of hafnium-free zirconium metal, which is used principally for sheathing fuel elements in nuclear reactors and in the chemical-processing industry, aerospace engineering, and electronics. Australia and South Africa are the largest zircon producers and account for more than 70 percent of world output; the United States and the Soviet Union account for another 20 percent. South Africa accounts for almost all the world's production of baddeleyite, which is about 2 percent of world production of contained zirconia. Australia and South Africa are the largest exporters of zircon. Unless major new deposits are developed in countries that have not traditionally produced zircon, the pattern of world production is unlikely to change by 2020. The proportions, however, of production that come from existing producing countries may change somewhat.

Towner, R.R.

1992-01-01

51

Zirconium oxidation on the atomic scale.  

PubMed

Zirconium alloys are used in the nuclear industry as fuel rod cladding. They are chosen for this role because of their good mechanical properties and low thermal neutron absorption. Oxidation of these alloys by coolant is one of the chief limiting factors of the fuel burn-up efficiency. The aim of the present study is to understand these oxidation mechanisms. As a first step, a fundamental study of the oxidation of commercially pure zirconium has been conducted using the 3D atom probe (3DAP). The current generation of 3DAPs allows both voltage and laser pulsing, providing data sets of many millions of ions. According to the literature the only stable oxide of zirconium is ZrO(2). However, the 3DAP shows that an initial layer a few nanometres thick forms with a composition of ZrO(1-)(x) when subjected to light oxidation. This result confirms and extends the work of Wadman et al. [Colloque de Physique 50 (1989) C8 303; Journal de Physique, 11 (1988) C6 49] and Wadman and Andrén [in: C.M. Euchen, A.M. Garde (Eds.), Zirconium in the Nuclear Industry: Ninth Symposium, ASTM STP 1132, ASTM, USA, 1991, p. 461], who used 1DAP techniques, obtaining reduced data sets. Segregation of hydrogen to the metal-oxide interface and a distinct ZrH phase were observed in this study. A novel kinetics study of the room temperature oxidation of zirconium showed the ZrO layer to be non-protective over the time period investigated (up to 1h). PMID:19101084

Hudson, Daniel; Cerezo, Alfred; Smith, George D W

2009-04-01

52

40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.  

Code of Federal Regulations, 2013 CFR

...Applicability; description of the zirconium-hafnium forming subcategory. 471.90 Section...POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory. This...

2013-07-01

53

40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.  

Code of Federal Regulations, 2012 CFR

...Applicability; description of the zirconium-hafnium forming subcategory. 471.90 Section...POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory. This...

2012-07-01

54

40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.  

...Applicability; description of the zirconium-hafnium forming subcategory. 471.90 Section...POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory. This...

2014-07-01

55

40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.  

Code of Federal Regulations, 2011 CFR

...Applicability; description of the zirconium-hafnium forming subcategory. 471.90 Section...POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory. This...

2011-07-01

56

The kinetics of solid nucleation in zirconium  

SciTech Connect

The framework of classical nucleation theory coupled with statistical analysis was used to evaluate nucleation data from zirconium undercooling experiments. Bulk samples of high purity zirconium were processed in a containerless, high vacuum environment using electrostatic levitation at Space Systems/Loral in order to obtain sets of nucleation temperature data. The relationships between undercooling and initial material purity have been investigated. The nucleation rate equation parameters, preexponential factor and work of cluster formation, were determined using a statistical analysis technique. The mean undercooling values ranged from 326 to 348 K for material purities between 99.8 and 99.995%, respectively. The range of values for the preexponential factors, 10{sup 32}--10{sup 43}, and the activation energies, 64--88kT, for the classical nucleation rate equation also scaled with the purity levels.

Morton, C.W. [Teledyne Advanced Materials, La Vergne, TN (United States)] [Teledyne Advanced Materials, La Vergne, TN (United States); Hofmeister, W.H.; Bayuzick, R.J. [Vanderbilt Univ., Nashville, TN (United States)] [Vanderbilt Univ., Nashville, TN (United States); Rulison, A.J.; Watkins, J.L. [Space Systems/Loral, Palo Alto, CA (United States)] [Space Systems/Loral, Palo Alto, CA (United States)

1998-11-02

57

Fatigue behavior of alpha-zirconium phosphate/epoxy nanocomposites.  

E-print Network

??Fatigue crack growth in ?-Zirconium phosphate/epoxy nanocomposites was investigated. A new fatigue testing technique was implemented for miniature samples. Two different methods ?strength of materials… (more)

Varadharajan, Balaji R.

2006-01-01

58

Procedures for heat treating fabricated equipment of zirconium alloys  

SciTech Connect

Zirconium is a common corrosion resistant material of construction used in a variety of chemical and industrial applications. In some applications, heat treatment is required or desirable after equipment fabrication to optimize the corrosion resistance and/or mechanical properties. Heat treatment can be performed using standard processes used for other materials but special attention should be given to zirconium`s properties when heat treatment is considered. This paper covers those conditions where heat treatment of zirconium equipment is utilized and describes the various heat treatment types and procedures.

Sutherlin, R.C. [Teledyne Wah Chang, Albany, OR (United States)

1995-10-01

59

Spectrum of Trebly Ionized Zirconium (Zr IV)  

Microsoft Academic Search

The zirconium spectrum is recorded on the 3 m normal incidence spectrograph of the Physics Department, Lund University; analysis of Zr IV is revised and extended. Identification of thirty-four 4p6 nd-4p5 4d2 (n = 4, 5, 6) transitions led to establish twelve 4p5 4d2 levels. Fifteen transitions are added to the analysis of the one-electron spectrum, establishing 7p levels and

K. Rahimullah; Zainul Abedeen Khan; M. S. Z. Chaghtai

1980-01-01

60

Spectrum of Trebly Ionized Zirconium (Zr IV)  

Microsoft Academic Search

The zirconium spectrum is recorded on the 3 m normal incidence spectrograph of the Physics Department, Lund University; analysis of Zr IV is revised and extended. Identification of thirty-four 4p6nd-4p5 4d2 (n = 4, 5, 6) transitions led to establish twelve 4p5 4d2 levels. Fifteen transitions are added to the analysis of the one-electron spectrum, establishing 7p levels and revising

K Rahimullah; Zainul Abedeen Khan; M S Z Chaghtai

1980-01-01

61

Autohydration of Nanosized Cubic Zirconium Tungstate  

PubMed Central

Nanoparticulate zirconium tungstate prepared through hydrothermal methods was found to autohydrate under ambient conditions. This results in positive thermal expansion, limiting its usefulness for controlled thermal expansion composites. TEM and BET studies provided strong evidence that the cause of autohydration is a result of structural defects present in the nanoparticles, while kinetics are governed by surface area, suggesting that processing methods can be used to minimize or overcome this problem. PMID:20521830

2010-01-01

62

Fluorometric determination of zirconium in minerals  

USGS Publications Warehouse

The increasing use of zirconium in alloys and in the ceramics industry has created renewed interest in methods for its determination. It is a common constituent of many minerals, but is usually present in very small amounts. Published methods tend to be tedious, time-consuming, and uncertain as to accuracy. A new fluorometric procedure, which overcomes these objections to a large extent, is based on the blue fluorescence given by zirconium and flavonol in sulfuric acid solution. Hafnium is the only element that interferes. The sample is fused with borax glass and sodium carbonate and extracted with water. The residue is dissolved in sulfuric acid, made alkaline with sodium hydroxide to separate aluminum, and filtered. The precipitate is dissolved in sulfuric acid and electrolysed in a Melaven cell to remove iron. Flavonol is then added and the fluorescence intensity is measured with a photo-fluorometer. Analysis of seven standard mineral samples shows excellent results. The method is especially useful for minerals containing less than 0.25% zirconium oxide.

Alford, W.C.; Shapiro, L.; White, C.E.

1951-01-01

63

Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 1  

E-print Network

Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 1 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 2 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 3 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 4 CTD096 #12;Hickey, TT136

Hickey, Barbara

64

Magnetic properties of nickel alloys with zirconium, niobium, and tungsten  

Microsoft Academic Search

The saturation magnetization and Curie point of nickel-- zirconium ; alloys were found to decrease with zirconium content. The saturation ; magnetization and Curie point are given by the formulas ( sigma \\/sub alloy\\/\\/ ; sigma \\/sub Ni\\/) = exp (-g\\/g\\/sub k\\/), and ) theta \\/sup alloy\\/\\/ theta \\/sup Ni\\/) = 1 ; - g( partial delta \\/ partial delta

A. D. Evdokimova; E. M. Sokolovskaya

1973-01-01

65

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

188 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida and at one mine in Virginia. Zirconium and hafnium metal, chemicals, metal alloys, welding rod coatings, and sandblasting. The largest market for hafnium metal

66

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

192 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida and one mine in Virginia. Zirconium and hafnium metal, chemicals, metal alloys, welding rod coatings, and sandblasting. The largest market for hafnium metal

67

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida and at one mine in Virginia. Zirconium and hafnium metal, metal alloys, welding rod coatings, and sandblasting. The largest market for hafnium metal

68

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless noted)  

E-print Network

190 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida. Zirconium and hafnium metal were produced from zircon sand, welding rod coatings, and sandblasting. The largest market for hafnium metal is as an addition

69

ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)  

E-print Network

192 ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted) Domestic Production and Use: Zircon sand was produced at two mines in Florida. Zirconium and hafnium metal were produced from zircon, chemicals, metal alloys, welding rod coatings, and sandblasting. The largest market for hafnium metal

70

Processes for producing improved wear resistant coatings on zirconium shapes  

SciTech Connect

This patent describes the process of producing a zirconium oxide water resistant coating on a zirconium alloy surface comprising treating the alloy in a molten salt bath heated to a temperature of between 550/sup 0/ and 800/sup 0/C containing small amounts of sodium carbonate.

Haygarth, J.C.

1987-06-09

71

Corrosion resistance of zirconium and zirconium-titanium alloy in hot nitric acid  

Microsoft Academic Search

Since zirconium (Zr) has superior corrosion resistance to concentrated nitric acid (HNO3) at elevated temperature, it has been successfully used as a material for chemical plants to produce HNO3 or spent nuclear fuel reprocessing plants. However, the occurrence of stress corrosion cracking (SCC) has recently been reported in hot nitric acid conditions. The necessary conditions for SCC in Zr, and

Hiroo Nagano; Haruhiko Kajimura; Kazuo Yamanaka

1995-01-01

72

Zirconium fluoride glass - Surface crystals formed by reaction with water  

NASA Technical Reports Server (NTRS)

The hydrated surfaces of a zirconium barium fluoride glass, which has potential for application in optical fibers and other optical elements, were observed by scanning electron microscopy. Crystalline zirconium fluoride was identified by analysis of X-ray diffraction patterns of the surface crystals and found to be the main constituent of the surface material. It was also found that hydrated zirconium fluorides form only in highly acidic fluoride solutions. It is possible that the zirconium fluoride crystals form directly on the glass surface as a result of its depletion of other ions. The solubility of zirconium fluoride is suggested to be probably much lower than that of barium fluoride (0.16 g/100 cu cm at 18 C). Dissolution was determined to be the predominant process in the initial stages of the reaction of the glass with water. Penetration of water into the glass has little effect.

Doremus, R. H.; Bansal, N. P.; Bradner, T.; Murphy, D.

1984-01-01

73

Irradiation growth in zirconium and its alloys  

NASA Astrophysics Data System (ADS)

The UKAEA Northern Research Laboratories (Risley) have recently completed an underlying research study on irradiation growth in zirconium and its alloys. During this study, irradiation growth measurements have been made on a range of well-characterized single-crystal and polycrystalline iodide zirconium, commercial alloys Zircaloy-2 and Zr-2.5 wt% Nb, and high-purity zirconium-tin alloys in different metallurgical conditions following irradiation in the DIDO reactor at AERE Harwell. Irradiations were performed in three rigs operating at irradiation temperatures between 353 and 673 K. An important feature of the experimental programme was the capability to perform repeat length measurements on individual growth specimens at intervals during their irradiation programme. This facility has allowed accurate monitoring of the growth phenomenon and changes in growth behaviour induced by the combined effects of irradiation temperature and accumulated fast neutron dose over large dose ranges. This paper reviews the main experimental results from this programme and discusses them in terms of current understanding of the growth process. Thus, it has been observed that, in annealed Zircaloy-2 at temperatures between 553 and 673 K, a transition from saturating growth to accelerating growth rates occurs with increasing dose. The dose above which this "growth breakaway" takes place is seen to be inversely dependent on irradiation temperature in mis temperature range. The well-documented difference in growth behaviour between annealed and cold-worked Zircaloy-2 observed at relatively low irradiation temperatures, in which cold-worked material grows at a high linear rate over large dose ranges, is not observed at 673 K. Comparison is made with reported results on similar material irradiated in other irradiation facilities. The growth data are interpreted in terms of recent theories regarding the development during fast neutron irradiation of a cold-worked microstructure consisting of < a>- and < c>-type dislocations. Irradiation growth behaviour of annealed polycrystalline iodide zirconium between 353 and 673 K contrasts strongly with that in annealed Zircaloy-2 with low irradiation growth rates being observed over a large dose and temperature range. The influence of key irradiation parameters on the growth process have been examined in a series of studies initiated as part of a collaborative programme with AECL Chalk River Nuclear Labs. Final results from the studies on annealed and deformed single-crystal zirconium are reported here. They show that growth saturates rapidly at low dose in annealed single-crystal material irradiated at 353 and 553 K but that a gradual increase in growth strain is observed on irradiation to high dose at 553 K. Single-crystal specimens heavily swaged prior to irradiation at 353 K and given different pre-irradiation heat-treatments exhibit high near-linear or accelerating growth rates. These growth data are interpreted in terms of the importance of grain boundaries and twin boundaries as sinks for point defects which allow point defect separation and hence growth to continue to high dose. Finally, the results of growth experiments performed on Zr-0.1% Sn and Zr-1.5% Sn alloys at 353 and 553 K are reviewed. These experiments confirm the important role played by alloying additions and impurities on the growth process in zirconium and Zircaloy-2.

Rogerson, A.

1988-10-01

74

The Chemistry of Aqueous Solutions of Zirconium Salts (does the Zirconyl Ion EXIST?)  

Microsoft Academic Search

CONTENTS I. Introduction 656 II. Historical review 656 III. Properties of aqueous solutions of zirconium salts 657 IV. Complex formation by zirconium in aqueous and acidic solutions of its salts 660 V. Preparative chemistry of zirconium compounds and its relation to the chemical state of zirconium in solutions 664 Bibtex entry for this abstract Preferred format for this abstract (see

A. S. Solovkin; Z. N. Tsvetkova

1962-01-01

75

THE CHEMISTRY OF AQUEOUS SOLUTIONS OF ZIRCONIUM SALTS (DOES THE ZIRCONYL ION EXIST?)  

Microsoft Academic Search

CONTENTS I. Introduction 656 II. Historical review 656 III. Properties of aqueous solutions of zirconium salts 657 IV. Complex formation by zirconium in aqueous and acidic solutions of its salts 660 V. Preparative chemistry of zirconium compounds and its relation to the chemical state of zirconium in solutions 664

A S Solovkin; Z N Tsvetkova

1962-01-01

76

Polymerization of propylene promoted by zirconium benzamidinates.  

PubMed

New bis(N,N-trimethylsilylarylamidinate) zirconium dichloride complexes with various carbon substituents were prepared, and their solid as well as solution state structures were studied. In the polymerization of propylene, after activation by MAO, these catalysts provided two fractions. Ether soluble polymers were obtained at a low activity as sticky polymers with lower molecular weights, except with the o-OMe substituted complex. The solid fractions were composed of a highly isotactic polymer and a moderately syndiotactic polymer. An interesting linear correlation was found between the rates of the 2,1 and 3,1 insertions for the ether soluble fractions. PMID:24077612

Aharonovich, Sinai; Kulkarni, Naveen V; Zhang, Jia-Sheng; Botoshansky, Mark; Kapon, Moshe; Eisen, Moris S

2013-12-28

77

Electron-momentum distribution in zirconium  

SciTech Connect

The electron-momentum distribution in hexagonal-close-packed zirconium has been studied for the first time with use of a Compton-scattering technique. Measurements have been made by scattering 59.54-keV ..gamma.. rays. Theoretical computations have been carried out with use of the renormalized-free-atom model for various 4d-5s configurations. Best agreement between theory and experiment is found if the electron configuration is chosen as 4d/sup 3/5s/sup 1/.

Sharma, B.K.; Ahuja, B.L.

1988-08-15

78

Laser Photodetachment Electron Spectroscopy of Zirconium Dimers  

NASA Astrophysics Data System (ADS)

The electron affinity of the zirconium dimer has been measured using laser photodetachment electron spectroscopy (LPES). A photon beam emitted from a 532.2 nm CW laser crossed a 10 KeV beam of Zr2^- ions at a 90^o collision angle. The kinetic energies of the photodetached electrons were measured with a 160^o spherical sector energy analyzer. The electron spectrometer was operated in the constant pass energy mode.Photoelectron spectra were used to determine the electron affinity of the Zr2. Moreover, studies of photoelectron angular distribution measurements were also performed. Analysis of the angular distribution data is in process, and preliminary results will be presented.

Duvvuri, Srividya

2005-03-01

79

Art History 97 Art History  

E-print Network

Art History 97 Art History The School of Humanities Degrees Offered: BA The Department of Art History offers a wide range of courses in European, American,Asian, and Middle Eastern/Islamic art history with additional strengths in architectural history and film and media studies.The major in art history is struc

Richards-Kortum, Rebecca

80

Factors to consider for using zirconium in sulfuric acid services  

SciTech Connect

Zirconium is a pivotal material often specified for process equipment that handles highly corrosive sulfuric acid solutions. Because of the complicated nature of sulfuric acid, several factors should be addressed to ensure the durability of zirconium equipment. These factors include acid concentration, temperature, pressure, impurity, stress, crevices, welding, and surfaces condition. Depending on the situation, certain potential hazards to zirconium equipment can be prevented by applying control measures such as heat treatment, proper design and operating, inhibitor, surface conditioning and/or shot peening.

Fitzgerald, B.J. [Exxon Chemical Co., Baytown, TX (United States); Webber, R.G. [Exxon Chemical Co., Baton Rouge, LA (United States); Frechem, B.S. [Rohm and Haas Co., Spring House, PA (United States); Briegel, K.F. [Rohm and Haas Texas Co., Deer Park, TX (United States); Yau, T.L. [Teledyne Wah Chang, Albany, OR (United States)

1995-10-01

81

Ballistic effectiveness of superdense solid composite propellants with zirconium or zirconium hydride  

NASA Astrophysics Data System (ADS)

The ballistic effectiveness of propellants depends not only on the value of specific impulse but also on many other performances, primarily on the density. Despite the density itself does not enter the expression of the rocket velocity (W = Isp ln(Mlaunch/Mfinish) where Mlaunch and Mfinish are the rocket launch mass and its mass after the propellant is burnt, respectively), it in§uences the value Mlaunch/Mfinish of the specific rocket. If one charges the construction of fixed volume with a more dense propellant, the ratio Mlaunch/Mfinish increases and, consequently, W increases as well. In this paper, the possibility of creating solid composite propellants (SCP) with zirconium (density 6.49 g/cm3) and zirconium hydride (density 5.61 g/cm3 ) as energetic compounds instead of aluminum is considered. It was found for what kinds of engines these propellants have to be more effective than propellants based on aluminum.

Lempert, D.; Manelis, G.; Nechiporenko, G.

2011-10-01

82

Fatigue behavior of alpha-zirconium phosphate/epoxy nanocomposites  

E-print Network

Fatigue crack growth in ±-Zirconium phosphate/epoxy nanocomposites was investigated. A new fatigue testing technique was implemented for miniature samples. Two different methods ?strength of materials and Rayleigh-Ritz - were used in determining...

Varadharajan, Balaji R.

2006-04-12

83

Investigation of Electrochemical Recovery of Zirconium from Spent Nuclear Fuels  

SciTech Connect

This project uses both modeling and experimental studies to design optimal electrochemical technology methods for recovery of zirconium from used nuclear fuel rods for more effective waste management. The objectives are to provide a means of efficiently separating zirconium into metallic high-level waste forms and to support development of a process for decontamination of zircaloy hulls to enable their disposal as low- and intermediate-level waste. Modeling work includes extension of a 3D model previously developed by Seoul National University for uranium electrorefining by adding the ability to predict zirconium behavior. Experimental validation activities include tests for recovery of zirconium from molten salt solutions and aqueous tests using surrogate materials. *This is a summary of the FY 2013 progress for I-NERI project # 2010-001-K provided to the I-NERI office.

Michael Simpson; II-Soon Hwang

2014-06-01

84

Electrical resistivity and thermal expansion of liquid titanium and zirconium  

SciTech Connect

The electrical resistivity and thermal expansion have been measured to twofold expanded states for titanium and to 60% expanded states for zirconium using the isobaric expansion apparatus. Results are consistent with the literature where there is overlap.

Gathers, G.R.

1983-01-01

85

Electrochemical study of corrosion phenomena in zirconium alloys  

E-print Network

Shadow corrosion of zirconium alloy fuel cladding in BWR environments, the phenomenon in which accelerated corrosion is experienced when the cladding surface is in close proximity to other metals, has become a potentially ...

Treeman, Nicole M

2005-01-01

86

Delayed hydride cracking of zirconium alloys  

SciTech Connect

High-strength zirconium alloys are susceptible to a mechanism for crack initiation and propagation termed delayed hydride cracking (DHC). In these alloys, it is possible to generate a large enough stress gradient so that hydrogen moves to the highly stressed areas. Therefore, hydrides precipitate and grow in these areas. When the tensile stress is sufficiently great, crack initiation starts at some of these hydrides. Crack propagation occurs by repeating the same process at the crack tip. Of concern for the chemical process industries is the DHC of Zr-2.5Nb welds. Results of long-term tests and case histories indicate that stress relieving is one of the major measures for preventing DHC, provided that ASME mechanical requirements are met.

Yau, T.L. [Teledyne Wah Chang, Albany, OR (United States); Webster, R.T. [Webster (R.T.), Scio, OR (United States)

1995-10-01

87

Zirconium Hydride Space Power Reactor design.  

NASA Technical Reports Server (NTRS)

The Zirconium Hydride Space Power Reactor being designed and fabricated at Atomics International is intended for a wide range of potential applications. Throughout the program a series of reactor designs have been evaluated to establish the unique requirements imposed by coupling with various power conversion systems and for specific applications. Current design and development emphasis is upon a 100 kilowatt thermal reactor for application in a 5 kwe thermoelectric space power generating system, which is scheduled to be fabricated and ground tested in the mid 70s. The reactor design considerations reviewed in this paper will be discussed in the context of this 100 kwt reactor and a 300 kwt reactor previously designed for larger power demand applications.

Asquith, J. G.; Mason, D. G.; Stamp, S.

1972-01-01

88

Zirconium deformation behavior: insights from EBSD measurements.  

SciTech Connect

The deformation of crystal-bar zirconium was investigated as a function of strain and strain rate through electron back-scattered diffraction (EBSD) characterization. The resultant data provided spatially resolved information on microstructure and texture evolution, individual twin system activity, and subsequent strain partitioning between twinned volume and parent grains. A range of deformation conditions was represented through quasi-static compression, 4-point beam bend tests at room and cryogenic temperature, and Taylor cylinder impact experiments. Effects from the interplay between slip and twinning deformation modes on anisotropic plasticity are considered in order to address the apparent trend toward isotropy at high rates. The role of various length scales on deformation behavior will be considered, along with the implications of these length scales on the assumptions typically invoked for plasticity modeling.

Bingert, J. F. (John F.); Mason, T. A. (Thomas A.); Kaschner, G. C. (George C.); Maudlin, P. J. (Paul J.); Gray, G. T. (George T.), III

2001-01-01

89

A Zirconium Cermet for Transuranic Isotope Storage and Burning  

SciTech Connect

Transuranic (TRU) isotopes comprise {approx} 1% of the spent nuclear fuel (SNF) inventory from commercial light water reactors and supply the majority of the late-term (>300 years) heat load produced by SNF. These isotopes also have significant potential fission energy content that could be recovered in a fast reactor or accelerator driven system. Estimates by Wigeland, et al. suggest that removal of 99.9% of TRU isotopes and 97% of cesium, strontium, and europium from SNF could increase the linear drift load (i.e. capacity) of the proposed geologic repository at Yucca Mountain, NV by an order of magnitude. In other words, the waste packing capacity in Yucca Mt. would be increased and the recovered TRU could be used in a fast reactor system for energy production. One of the goals of the Advanced Fuel Cycle Initiative (AFCI) of the U.S. Department of Energy is to develop advanced nuclear technologies to recycle spent nuclear fuel without separating pure plutonium. The UREX+ family of solvent extraction and ion exchange processes can be manipulated to isolate TRU isotopes from uranium and other short-lived isotopes while leaving the Pu intimately mixed with other minor actinides (this corresponds with the UREX+1a process). The product TRU nitrate solution can be converted into oxide microspheres via direct denitration or sol-gel processing, leaving the TRU product in a stable oxide form for further processing. In addition, nuclear-grade zirconium metal can be recovered by recycling Zircaloy from the spent fuel cladding after the fuel has been chopped and dissolved away. The Zircaloy cladding hulls may be processed via a hydride/de-hydride process to produce high purity zirconium powder.These powder products can be combined via powder metallurgy techniques to produce a stable, safe storage form for TRU waste with the possibility of converting a long term waste liability into an advanced energy resource. Previous work by McDeavitt et al. at Argonne National Laboratory analyzed the production of a (Th,U)O-2-Zr cermet fuel using a cold-drawing process. This was a multi-pass process wherein a series of reductions were performed on each individual rod with a high temperature anneal between successive reductions to relieve strain hardening. This process allowed excellent control over the finished product matrix density allowing the user to pre-select the desired density by manipulating the reduction scheme. The final cold-drawn cermet contained a large fraction of damaged oxide particles, though the cause of this damage was not investigated due to project time constraints. It is believed that the high stress profile developed during cold deformation was the primary cause of this damage. The Fuel Cycle and Materials Laboratory (FCML) at Texas A and M University is currently analyzing a hot extrusion process to fabricate the proposed cermet and provide comparison data with the previous work. Initial studies have been completed and a system redesign is near completion. This paper presents the initial findings of the initial work and describes the new system setup. (authors)

Totemeier, Aaron R.; McDeavitt, Sean M. [Fuel Cycle and Materials Laboratory, Texas A and M University, College Station, TX 77843 (United States)

2007-07-01

90

Critical role of nitrogen during high temperature scaling of zirconium  

NASA Technical Reports Server (NTRS)

The mechanisms of scale cracking, scale color changes, and scale growth, and their interrelations, were studied in zirconium specimens at elevated temperatures in air, oxygen and nitrogen. Nitrogen was found to be responsible for monoclinic-to-cubic ZrO2 conversion, for scale cracking and breakaway on zirconium nitride, and for the formation of ZrN on the metal interface underneath an outer oxide layer.

Evans, E. B.; Tsangarakis, N.; Probst, H. B.; Garibotti, N. J.

1973-01-01

91

Material property correlations for the niobium-1% zirconium alloy  

E-print Network

MATERIAL PROPERTY CORRELATIONS FOR THE NIOBIUM-1% ZIRCONIUM ALLOY A Thesis by DAVID JAMES SENOR Submitted to the Office of Graduate Studies of Texas A6&l University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1989 Major Subject: Nuclear Engineering MATERIAL PROPERTY CORRELATIONS FOR THE NIOBUIM-1% ZIRCONIUM ALLOY A Thesis by DAVID JAMES SENOR Approved as to style and content by; . L. Peddicord (Chair of Committee) Frederick R. Best...

Senor, David James

2012-06-07

92

40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...  

Code of Federal Regulations, 2011 CFR

...products with alkanol zirconium(4+) salt and silica, acetates (generic). 721...products with alkanol zirconium(4+) salt and silica, acetates (generic). ...products with alkanol zirconium(4+) salt and silica, acetates (PMN...

2011-07-01

93

40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...  

...products with alkanol zirconium(4+) salt and silica, acetates (generic). 721...products with alkanol zirconium(4+) salt and silica, acetates (generic). ...products with alkanol zirconium(4+) salt and silica, acetates (PMN...

2014-07-01

94

47 CFR 97.511 - Examinee conduct.  

Code of Federal Regulations, 2010 CFR

...Section 97.511 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.511 Examinee conduct. Each examinee must comply with the...

2010-10-01

95

47 CFR 97.511 - Examinee conduct.  

Code of Federal Regulations, 2011 CFR

...Section 97.511 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.511 Examinee conduct. Each examinee must comply with the...

2011-10-01

96

47 CFR 97.511 - Examinee conduct.  

Code of Federal Regulations, 2013 CFR

...Section 97.511 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.511 Examinee conduct. Each examinee must comply with the...

2013-10-01

97

47 CFR 97.511 - Examinee conduct.  

Code of Federal Regulations, 2012 CFR

...Section 97.511 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.511 Examinee conduct. Each examinee must comply with the...

2012-10-01

98

46 CFR 111.97-1 - Applicability.  

Code of Federal Regulations, 2011 CFR

...111.97-1 Section 111.97-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems §...

2011-10-01

99

27 CFR 71.97 - Powers.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Powers. 71.97 Section...TREASURY (CONTINUED) PROCEDURES AND PRACTICES ...Administrative Law Judges § 71.97 Powers. Administrative law judges shall have...the Administrative Procedure Act. [21...

2010-04-01

100

Quercetin as colorimetric reagent for determination of zirconium  

USGS Publications Warehouse

Methods described in the literature for the determination of zirconium are generally designed for relatively large amounts of this element. A good procedure using colorimetric reagent for the determination of trace amounts is desirable. Quercetin has been found to yield a sensitive color reaction with zirconium suitable for the determination of from 0.1 to 50?? of zirconium dioxide. The procedure developed involves the separation of zirconium from interfering elements by precipitation with p-dimethylaminoazophenylarsonic acid prior to its estimation with quercetin. The quercetin reaction is carried out in 0.5N hydrochloric acid solution. Under the operating conditions it is indicated that quercetin forms a 2 to 1 complex with zirconium; however, a 2 to 1 and a 1 to 1 complex can coexist under special conditions. Approximate values for the equilibrium constants of the complexes are K1 = 0.33 ?? 10-5 and K2 = 1.3 ?? 10-9. Seven Bureau of Standards samples of glass sands and refractories were analyzed with excellent results. The method described should find considerable application in the analysis of minerals and other materials for macro as well as micro amounts of zirconium.

Grimaldi, F.S.; White, C.E.

1953-01-01

101

47 CFR 97.503 - Element standards.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

2010-10-01

102

47 CFR 97.503 - Element standards.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

2011-10-01

103

47 CFR 97.505 - Element credit.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

2011-10-01

104

47 CFR 97.505 - Element credit.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

2010-10-01

105

7 CFR 97.14 - Joint applicants.  

Code of Federal Regulations, 2013 CFR

...Agriculture 3 2013-01-01 2013-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

2013-01-01

106

7 CFR 97.14 - Joint applicants.  

Code of Federal Regulations, 2012 CFR

...Agriculture 3 2012-01-01 2012-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

2012-01-01

107

7 CFR 97.14 - Joint applicants.  

Code of Federal Regulations, 2011 CFR

...Agriculture 3 2011-01-01 2011-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

2011-01-01

108

7 CFR 97.14 - Joint applicants.  

Code of Federal Regulations, 2010 CFR

...Agriculture 3 2010-01-01 2010-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

2010-01-01

109

7 CFR 97.14 - Joint applicants.  

...Agriculture 3 2014-01-01 2014-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

2014-01-01

110

40 CFR 97.155 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.155 Section 97.155 Protection of Environment...PROGRAMS CAIR NOX Allowance Tracking System § 97.155 Banking. (a) CAIR NOX allowances may be banked for...

2012-07-01

111

40 CFR 97.526 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.526 Section 97.526 Protection of Environment...PROGRAMS TR NOX Ozone Season Trading Program § 97.526 Banking. (a) A TR NOX Ozone Season allowance may be...

2012-07-01

112

40 CFR 97.55 - Banking.  

Code of Federal Regulations, 2011 CFR

...Environment 21 2011-07-01 2011-07-01 false Banking. 97.55 Section 97.55 Protection of Environment...TRADING PROGRAMS NOX Allowance Tracking System § 97.55 Banking. NOX allowances may be banked for future use or...

2011-07-01

113

40 CFR 97.155 - Banking.  

Code of Federal Regulations, 2010 CFR

...Environment 20 2010-07-01 2010-07-01 false Banking. 97.155 Section 97.155 Protection of Environment...PROGRAMS CAIR NOX Allowance Tracking System § 97.155 Banking. (a) CAIR NOX allowances may be banked for...

2010-07-01

114

40 CFR 97.355 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.355 Section 97.355 Protection of Environment...CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be...

2012-07-01

115

40 CFR 97.255 - Banking.  

Code of Federal Regulations, 2010 CFR

...Environment 20 2010-07-01 2010-07-01 false Banking. 97.255 Section 97.255 Protection of Environment...PROGRAMS CAIR SO2 Allowance Tracking System § 97.255 Banking. (a) CAIR SO2 allowances may be banked for...

2010-07-01

116

40 CFR 97.426 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.426 Section 97.426 Protection of Environment...TRADING PROGRAMS TR NOX Annual Trading Program § 97.426 Banking. (a) A TR NOX Annual allowance may be banked...

2012-07-01

117

40 CFR 97.155 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.155 Section 97.155 Protection of Environment...PROGRAMS CAIR NOX Allowance Tracking System § 97.155 Banking. (a) CAIR NOX allowances may be banked for...

2013-07-01

118

40 CFR 97.426 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.426 Section 97.426 Protection of Environment...TRADING PROGRAMS TR NOX Annual Trading Program § 97.426 Banking. (a) A TR NOX Annual allowance may be banked...

2013-07-01

119

40 CFR 97.726 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.726 Section 97.726 Protection of Environment...TRADING PROGRAMS TR SO2 Group 2 Trading Program § 97.726 Banking. (a) A TR SO2 Group 2 allowance may be banked...

2012-07-01

120

40 CFR 97.155 - Banking.  

Code of Federal Regulations, 2011 CFR

...Environment 21 2011-07-01 2011-07-01 false Banking. 97.155 Section 97.155 Protection of Environment...PROGRAMS CAIR NOX Allowance Tracking System § 97.155 Banking. (a) CAIR NOX allowances may be banked for...

2011-07-01

121

40 CFR 97.526 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.526 Section 97.526 Protection of Environment...PROGRAMS TR NOX Ozone Season Trading Program § 97.526 Banking. (a) A TR NOX Ozone Season allowance may be...

2013-07-01

122

40 CFR 97.355 - Banking.  

Code of Federal Regulations, 2010 CFR

...Environment 20 2010-07-01 2010-07-01 false Banking. 97.355 Section 97.355 Protection of Environment...CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be...

2010-07-01

123

40 CFR 97.726 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.726 Section 97.726 Protection of Environment...TRADING PROGRAMS TR SO2 Group 2 Trading Program § 97.726 Banking. (a) A TR SO2 Group 2 allowance may be banked...

2013-07-01

124

40 CFR 97.255 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.255 Section 97.255 Protection of Environment...PROGRAMS CAIR SO2 Allowance Tracking System § 97.255 Banking. (a) CAIR SO2 allowances may be banked for...

2012-07-01

125

40 CFR 97.626 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.626 Section 97.626 Protection of Environment...TRADING PROGRAMS TR SO2 Group 1 Trading Program § 97.626 Banking. (a) A TR SO2 Group 1 allowance may be banked...

2013-07-01

126

40 CFR 97.355 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.355 Section 97.355 Protection of Environment...CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be...

2013-07-01

127

40 CFR 97.55 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.55 Section 97.55 Protection of Environment...TRADING PROGRAMS NOX Allowance Tracking System § 97.55 Banking. NOX allowances may be banked for future use or...

2012-07-01

128

40 CFR 97.255 - Banking.  

Code of Federal Regulations, 2011 CFR

...Environment 21 2011-07-01 2011-07-01 false Banking. 97.255 Section 97.255 Protection of Environment...PROGRAMS CAIR SO2 Allowance Tracking System § 97.255 Banking. (a) CAIR SO2 allowances may be banked for...

2011-07-01

129

40 CFR 97.255 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.255 Section 97.255 Protection of Environment...PROGRAMS CAIR SO2 Allowance Tracking System § 97.255 Banking. (a) CAIR SO2 allowances may be banked for...

2013-07-01

130

40 CFR 97.626 - Banking.  

Code of Federal Regulations, 2012 CFR

...Environment 22 2012-07-01 2012-07-01 false Banking. 97.626 Section 97.626 Protection of Environment...TRADING PROGRAMS TR SO2 Group 1 Trading Program § 97.626 Banking. (a) A TR SO2 Group 1 allowance may be banked...

2012-07-01

131

40 CFR 97.55 - Banking.  

Code of Federal Regulations, 2013 CFR

...Environment 22 2013-07-01 2013-07-01 false Banking. 97.55 Section 97.55 Protection of Environment...TRADING PROGRAMS NOX Allowance Tracking System § 97.55 Banking. NOX allowances may be banked for future use or...

2013-07-01

132

40 CFR 97.355 - Banking.  

Code of Federal Regulations, 2011 CFR

...Environment 21 2011-07-01 2011-07-01 false Banking. 97.355 Section 97.355 Protection of Environment...CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be...

2011-07-01

133

40 CFR 97.55 - Banking.  

Code of Federal Regulations, 2010 CFR

...Environment 20 2010-07-01 2010-07-01 false Banking. 97.55 Section 97.55 Protection of Environment...TRADING PROGRAMS NOX Allowance Tracking System § 97.55 Banking. NOX allowances may be banked for future use or...

2010-07-01

134

47 CFR 97.505 - Element credit.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

2012-10-01

135

47 CFR 97.505 - Element credit.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

2013-10-01

136

47 CFR 97.503 - Element standards.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

2012-10-01

137

47 CFR 97.503 - Element standards.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

2013-10-01

138

46 CFR 97.15-10 - Sanitation.  

Code of Federal Regulations, 2011 CFR

... Shipping 4 2011-10-01 2011-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

2011-10-01

139

46 CFR 97.15-10 - Sanitation.  

Code of Federal Regulations, 2010 CFR

... Shipping 4 2010-10-01 2010-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

2010-10-01

140

46 CFR 97.15-10 - Sanitation.  

Code of Federal Regulations, 2013 CFR

... Shipping 4 2013-10-01 2013-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

2013-10-01

141

46 CFR 97.15-10 - Sanitation.  

Code of Federal Regulations, 2012 CFR

... Shipping 4 2012-10-01 2012-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

2012-10-01

142

46 CFR 97.15-10 - Sanitation.  

... Shipping 4 2014-10-01 2014-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

2014-10-01

143

40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...  

Code of Federal Regulations, 2012 CFR

...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...oxirane, substituted silylmethyl-, hydrolysis products with alkanol...

2012-07-01

144

40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...  

Code of Federal Regulations, 2013 CFR

...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...oxirane, substituted silylmethyl-, hydrolysis products with alkanol...

2013-07-01

145

40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...  

Code of Federal Regulations, 2010 CFR

...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4...oxirane, substituted silylmethyl-, hydrolysis products with alkanol...

2010-07-01

146

Preliminary investigation of zirconium boride ceramals for gas-turbine blade applications  

NASA Technical Reports Server (NTRS)

Zirconium boride ZrB2 ceramals were investigated for possible gas-turbine-blade application. Included in the study were thermal shock evaluations of disks, preliminary turbine-blade operation, and observations of oxidation resistance. Thermal shock disks of the following three compositions were studied: (a) 97.5 percent ZrB2 plus 2.5 percent B by weight; (b) 92.5 percent ZrB2 plus 7.5 percent B by weight; and (c) 100 percent ZrB2. Thermal shock disks were quenched from temperatures of 1800 degrees, 2000 degrees, 2200 degrees, and 2400 degrees F. The life of turbine blades containing 93 percent ZrB2 plus 7 percent B by weight was determined in gas-turbine tests. The blades were run at approximately 1600 degrees F and 15,000 to 26,000 rpm. The thermal shock resistance of the 97.5 percent ZrB2 plus 2.5 percent boron ceramals compares favorably with that of TiC plus Co and TiC plus Ni ceramals. Oxidation of the disks during the thermal shock evaluation was slight for the comparatively short time (8.3 hr) up through 2000 degrees F. Oxidation of a specimen was severe, however, after 100 hours at 2000 degrees F. The turbine blade performance evaluation of the 93 percent ZrB2 plus 7 percent B composition was preliminary in scope ; no conclusions can be drawn.

Hoffman, Charles A

1953-01-01

147

Understanding the Irradiation Behavior of Zirconium Carbide  

SciTech Connect

Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

2013-10-11

148

Elimination of phosphate and zirconium in the high-activity fraction resulting from TRUEX partitioning of ICPP zirconium calcines  

SciTech Connect

Laboratory testing was undertaken with the aim of developing a TRUEX flowsheet that would efficiently remove actinides from solutions of dissolved zirconium calcine and minimize the glass volume produced from the ensuing high-activity fraction. A TRUEX flowsheet is recommended for testing in the 2-cm centrifugal contactor pilot-plant based on the results from this testing. These laboratory tests show that zirconium recovery in the high activity fraction is minimized by scrubbing with an optimized NHF concentration of 0.2 M. This NH4F concentration in the scrub allowed the HEDPA strip concentration to be reduced from 0.04 M to 0.004 M because HEDPA is not consumed by zirconium. Complete TRU stripping was also achieved in these laboratory tests with 0.004 M HEDPA. Data from the small-scale laboratory batch contact tests were used in the Generic TRUEX Model (GTM) to evaluate the proposed flowsheet under counter-current conditions. GTM results indicate the raffinate will meet the Class A non-TRU limit of < 10 nCi/g in six extraction stages (O/A = 1), and quantitative actinide recovery will be achieved with the 0.004 M HEDPA in six strip stages (O/A = 1). Only 6.6 % of the initial zirconium concentration is anticipated to be recovered with the actinides, indicating the four scrub stages (O/A = 3) efficiently removes zirconium from the TRUEX solvent. In addition to recommending an improved TRUEX flowsheet for testing in the 2-cm centrifugal contactor pilot-plant, this work has shown that small reductions in zirconium extraction drastically improves flowsheet performance. These small changes in zirconium extraction can be accomplished by modifying the calcine dissolution parameters. Therefore, further calcine dissolution testing followed by TRUEX testing with the resulting feed solutions is also recommended.

Brewer, K.N.; Tillotson, R.D.; Tullock, P.A. [and others

1997-07-01

149

Cathodoluminescence imaging of oxidised zirconium alloys  

NASA Astrophysics Data System (ADS)

Cathodoluminescence (CL) imaging techniques have been applied to the characterisation of the zirconium oxide films formed from binary Zr alloy matrices using a homemade CL imaging system attached to an Hitachi S-570 scanning electron microscope (SEM). Evidence from the CL images shows the involvement of the individual Zircaloy alloying elements in the luminescence process. ?-annealed and slow-cooled samples which have strongly segregated alloying elements at their grain boundaries showed strong CL signals from these areas. Use of this heat treatment was necessary to compensate for the low resolution of the equipment. Strong CL signals were observed also from cracks in the oxides on some alloys and are believed to be caused by the redistribution of iron to the region adjacent to the crack, but below the original surface. Increasing redistribution of Fe with increasing oxidation temperature is seen in the CL images. The cyclic behaviour observed in the weight gain measurements is also observed in the CL intensity measurements. Experimental data from this investigation support the theory that this phenomenon is caused by the successive formation of cracks parallel and normal to the plane of the metal matrix.

Yueh, H. Ken; Cox, Brian

2004-01-01

150

Simulating porous oxide films on zirconium alloys  

NASA Astrophysics Data System (ADS)

This paper reports an attempt to simulate thick porous thermal oxide films on zirconium alloy specimens by successively applying layers of sol-gel zirconia to an initial thin oxide film. The intent was to aid in the interpretation of impedance spectra obtained from porous oxide films. To the extent that double-peaked Bode plots of phase angle, similar to those obtained from thermal oxides, were obtained in the impedance spectra the attempt was successful. However, the impedance spectra obtained on the simulated films were insensitive to the number of sol-gel layers. The film always appeared to be a double layer film, which was interpreted as the thermal oxide (produced during sintering the sol-gel oxide) under the sol-gel oxide. The impedance spectra were also insensitive to the nature of the porosity, which took the form of multiple high aspect ratio cracks in the simulated oxide films rather than the small pores observed in thermal oxide films. Accurate comparisons of oxide thicknesses by interferometry and impedance measurements with mercury contacts were rendered difficult by evidence for internal reflections (at the sol-gel/thermal oxide interface) in the former and incomplete contact problems in the latter.

Cox, B.; Wong, Y.-M.

1995-03-01

151

Author's personal copy A reactive force-field for Zirconium and Hafnium Di-Boride  

E-print Network

Author's personal copy A reactive force-field for Zirconium and Hafnium Di-Boride Afif Gouissem reactions High temperature materials a b s t r a c t Zirconium and Hafnium Di-Boride are the two major. Introduction The aim of this study is to develop transferable reactive force fields for Zirconium and Hafnium

Sharma, Pradeep

152

Atomic Layer Deposition of Hafnium and Zirconium Oxides Using Metal Amide Precursors  

E-print Network

Atomic Layer Deposition of Hafnium and Zirconium Oxides Using Metal Amide Precursors Dennis M (ALD) of smooth and highly conformal films of hafnium and zirconium oxides was studied using six metal alkylamide precursors for hafnium and zirconium. Water was used as an oxygen source during these experiments

153

J. Am. Chem. SOC.1991, 113, 3829-3837 3829 Zirconium and Hafnium Polyhydrides. Preparation and  

E-print Network

J. Am. Chem. SOC.1991, 113, 3829-3837 3829 Zirconium and Hafnium Polyhydrides. Preparation Abstract: Treatment of the zirconium and hafnium tetrahydroborate complexes M(BH4)4with trimethylphosphine-ligand distances in the zirconium complex are slightly longer than those in the hafnium complex, as expected from

Girolami, Gregory S.

154

Synthesis and characterization of a mesoporous hydrous zirconium oxide used for arsenic removal from drinking water  

SciTech Connect

Powder (20-50 {mu}m) mesoporous hydrous zirconium oxide was prepared from a zirconium salt granular precursor. The effect of some process parameters on product morphology, porous structure and adsorption performance has been studied. The use of hydrous zirconium oxide for selective arsenic removal from drinking water is discussed.

Bortun, Anatoly; Bortun, Mila; Pardini, James [MELChemicals Inc, 500 Barbertown Point Breeze Road, Flemington, NJ 08822 (United States)] [MELChemicals Inc, 500 Barbertown Point Breeze Road, Flemington, NJ 08822 (United States); Khainakov, Sergei A. [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, 33006 Oviedo (Spain)] [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, 33006 Oviedo (Spain); Garcia, Jose R., E-mail: jrgm@uniovi.es [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, 33006 Oviedo (Spain)

2010-02-15

155

U.S. GEOLOGICAL SURVEY--MINERALS INFORMATION 1 ZIRCONIUM AND HAFNIUM  

E-print Network

.S. production and of zircon, zirconium oxide, or other zirconium chemicals. The consumption of zircon. Milled zircon production was nearly hafnium and is used in the chemical process industries because. (DuPont). Both producers mined heavy-mineral sand deposits in Florida. U.S. producers of zirconium

156

Corrosion kinetics under high pressure of steam of pure zirconium and zirconium alloys followed by in situ thermogravimetry  

NASA Astrophysics Data System (ADS)

A new experimental thermogravimetric device has been installed to study in situ the corrosion behaviour of zirconium alloys under high pressure of steam. Corrosion tests up to 5 MPa of steam pressure have been performed on two materials, pure zirconium and Zircaloy-4 (Zy4), at around 415 °C. The rate-limiting step assumption was experimentally verified on Zy4. Unlike pure zirconium, its oxidation rate is not dependent on steam pressure. The experimental result obtained on this material is consistent with an oxygen vacancy diffusion rate-limiting step. For pure zirconium, the kinetic law is nearly linear during the corrosion process, which leads to propose an interface reaction rate-limiting step. Moreover, according to the isotope exchange experiments, the oxygen diffusion in the oxide formed on pure zirconium under high pressure of steam is very fast compared to that in the oxide of Zy4, which supports the thermogravimetric results. Finally, the impact of the SPPs on the corrosion resistance is briefly discussed in the last part of this paper from photoelectrochemical results.

Dali, Yacoub; Tupin, Marc; Bossis, Philippe; Pijolat, Michèle; Wouters, Yves; Jomard, François

2012-07-01

157

In-situ stabilization of radioactive zirconium swarf  

DOEpatents

The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes. 6 figs.

Hess, C.C.

1999-08-31

158

Producing carbon nanotube dispersions using polynuclear zirconium benzoate  

NASA Astrophysics Data System (ADS)

Aqueous dispersions of polynuclear zirconium benzoate with molar ratios of Zr: C6H5COO = 3-6, stable at pH 3.25-3.87 and having "solubilities" of up to 20 mg/mL by ZrO2, are prepared; in such dispersions, benzoate decomposes to ZrO2 at 500°C. Adding thin multiwalled carbon nanotubes to these dispersions makes it possible to isolate stable dispersions that contain both zirconium and nanotubes, mixtures suitable for producing composite coatings. It is shown that the concentration of nanotubes in mixtures with ZrO2 can vary within 1.7-50.6 wt %.

Van Nguyen, Huu; Luu, Son Tung; Rakov, E. G.

2013-02-01

159

Variant selection and transformation texture in zirconium alloy Excel  

NASA Astrophysics Data System (ADS)

The crystallographic texture and variant selection during phase transformations in zirconium alloy Excel (Zr-3.5% Sn-0.8% Mo-0.8% Nb) was investigated. It was shown that upon water-quenching from ?Zr + ?Zr or fully ?Zr regions, variant selection occurs during ?Zr ? ??Zr martensitic transformation. Also during air-cooling from the ?Zr + ?Zr region, only a partial memory effect and some transformation texture with variant selection was observed which is contrary to previous reports on zirconium alloys heat treated in the ?Zr + ?Zr region.

Sattari, M.; Holt, R. A.; Daymond, M. R.

2014-10-01

160

In-situ stabilization of radioactive zirconium swarf  

DOEpatents

The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes.

Hess, Clay C. (Idaho Falls, ID)

1999-01-01

161

Experiments on explosive interactions between zirconium-containing melt and water (ZREX).  

SciTech Connect

The results of two series of experiments on explosive interactions between zirconium-containing melt and water are described. The first series of experiments involved dropping 1-kg batches of zirconium-zirconium dioxide mixture melt into a column of water while the second series employed 1.2-kg batches of zirconium-stainless steel mixture melt. Explosions took place only in those tests which were externally triggered. While the extent of zirconium oxidation in the triggered experiments was quite large, the explosion energies estimated from the experimental measurements were found to be small compared to the combined thermal and chemical energy available.

Cho, D. H.

1998-04-10

162

Zirconium determination by cooling curve analysis during the pyroprocessing of used nuclear fuel  

NASA Astrophysics Data System (ADS)

An alternative method to sampling and chemical analyses has been developed to monitor the concentration of zirconium in real-time during the casting of uranium products from the pyroprocessing of used nuclear fuel. The method utilizes the solidification characteristics of the uranium products to determine zirconium levels based on standard cooling curve analyses and established binary phase diagram data. Numerous uranium products have been analyzed for their zirconium content and compared against measured zirconium data. From this data, the following equation was derived for the zirconium content of uranium products:

Westphal, B. R.; Price, J. C.; Bateman, K. J.; Marsden, K. C.

2015-02-01

163

Stainless steel-zirconium alloy waste forms  

SciTech Connect

An electrometallurgical treatment process has been developed by Argonne National Laboratory to convert various types of spent nuclear fuels into stable storage forms and waste forms for repository disposal. The first application of this process will be to treat spent fuel alloys from the Experimental Breeder Reactor-II. Three distinct product streams emanate from the electrorefining process: (1) refined uranium; (2) fission products and actinides extracted from the electrolyte salt that are processed into a mineral waste form; and (3) metallic wastes left behind at the completion of the electrorefining step. The third product stream (i.e., the metal waste stream) is the subject of this paper. The metal waste stream contains components of the chopped spent fuel that are unaffected by the electrorefining process because of their electrochemically ``noble`` nature; this includes the cladding hulls, noble metal fission products (NMFP), and, in specific cases, zirconium from metal fuel alloys. The selected method for the consolidation and stabilization of the metal waste stream is melting and casting into a uniform, corrosion-resistant alloy. The waste form casting process will be carried out in a controlled-atmosphere furnace at high temperatures with a molten salt flux. Spent fuels with both stainless steel and Zircaloy cladding are being evaluated for treatment; thus, stainless steel-rich and Zircaloy-rich waste forms are being developed. Although the primary disposition option for the actinides is the mineral waste form, the concept of incorporating the TRU-bearing product into the metal waste form has enough potential to warrant investigation.

McDeavitt, S.M.; Abraham, D.P.; Keiser, D.D. Jr.; Park, J.Y.

1996-07-01

164

Antimicrobial effects of silver zeolite, silver zirconium phosphate silicate and silver zirconium phosphate against oral microorganisms  

PubMed Central

Objective To evaluate the antimicrobial activities of silver inorganic materials, including silver zeolite (AgZ), silver zirconium phosphate silicate (AgZrPSi) and silver zirconium phosphate (AgZrP), against oral microorganisms. In line with this objective, the morphology and structure of each type of silver based powders were also investigated. Methods The antimicrobial activities of AgZ, AgZrPSi and AgZrP were tested against Streptococcus mutans, Lactobacillus casei, Candida albicans and Staphylococcus aureus using disk diffusion assay as a screening test. The minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the modified membrane method. Scanning electron microscope and X-ray diffraction were used to investigate the morphology and structure of these silver materials. Results All forms of silver inorganic materials could inhibit the growth of all test microorganisms. The MIC of AgZ, AgZrPSi and AgZrP was 10.0 g/L whereas MLC ranged between 10.0–60.0 g/L. In terms of morphology and structure, AgZrPSi and AgZrP had smaller sized particles (1.5–3.0 µm) and more uniformly shaped than AgZ. Conclusions Silver inorganic materials in the form of AgZ, AgZrPSi and AgZrP had antimicrobial effects against all test oral microorganisms and those activities may be influenced by the crystal structure of carriers. These results suggest that these silver materials may be useful metals applied to oral hygiene products to provide antimicrobial activity against oral infection. PMID:23570016

Saengmee-anupharb, Sirikamon; Srikhirin, Toemsak; Thaweboon, Boonyanit; Thaweboon, Sroisiri; Amornsakchai, Taweechai; Dechkunakorn, Surachai; Suddhasthira, Theeralaksna; Kamaguchi, Arihide

2013-01-01

165

Plasma sprayed and electrospark deposited zirconium metal diffusion barrier coatings  

Microsoft Academic Search

Zirconium metal coatings applied by plasma spraying and electrospark deposition (ESD) have been investigated for use as diffusion barrier coatings on low enrichment uranium fuel for research nuclear reactors. The coatings have been applied to both stainless steel as a surrogate and to simulated nuclear fuel uranium-molybdenum alloy substrates. Deposition parameter development accompanied by coating characterization has been performed. The

Kendall J Hollis; Maria I Pena

2010-01-01

166

Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics  

E-print Network

Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics Adrien Couet a to reduce hydrogen pickup during operation, and the associated cladding degradation. The present study focuses on precisely and accurately measuring hydrogen pickup fraction for a set of alloys to specifically

Motta, Arthur T.

167

Manufacturing process to reduce large grain growth in zirconium alloys  

DOEpatents

A method of treating cold-worked zirconium alloys to reduce large grain gth during thermal treatment at temperatures above the recrystallization temperature of the alloy comprising heating the cold-worked alloy between about 1300.degree.-1350.degree. F. for 1 to 3 hours prior to treatment above its recrystallization temperature.

Rosecrans, Peter M. (Niskayuna, NY)

1987-01-01

168

Mineral resource of the month: zirconium and hafnium  

USGS Publications Warehouse

Zirconium and hafnium are corrosion-resistant metals that are grouped in the same family as titanium on the periodic table. The two elements commonly occur in oxide and silicate minerals and have significant economic importance in everything from ink, ceramics and golf shoes to nuclear fuel rods.

Gambogi, Joseph

2007-01-01

169

Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes  

E-print Network

Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

Nystrom, A

2011-01-01

170

Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes  

E-print Network

Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

A. Nystrom; M. Thoennessen

2011-02-11

171

CRYSTAL STRUCTURES OF TITANIUM, ZIRCONIUM, AND HAFNIUM AT HIGH PRESSURES  

Microsoft Academic Search

At high pressures, as determined by x-ray analysis, titanium and ; zirconium metal have a distorted, bodycentered-cubic structure. This phase ; persists on pressure release. The normal hexagonal close-packed structures are ; recovered when the metals are heated. An electronic shift must occur in the ; transition. Hafnium metal showed no such transition. (auth);

J. C. Jamieson

1963-01-01

172

Nanophase Nickel-Zirconium Alloys for Fuel Cells  

NASA Technical Reports Server (NTRS)

Nanophase nickel-zirconium alloys have been investigated for use as electrically conductive coatings and catalyst supports in fuel cells. Heretofore, noble metals have been used because they resist corrosion in the harsh, acidic fuel cell interior environments. However, the high cost of noble metals has prompted a search for less-costly substitutes. Nickel-zirconium alloys belong to a class of base metal alloys formed from transition elements of widely different d-electron configurations. These alloys generally exhibit unique physical, chemical, and metallurgical properties that can include corrosion resistance. Inasmuch as corrosion is accelerated by free-energy differences between bulk material and grain boundaries, it was conjectured that amorphous (glassy) and nanophase forms of these alloys could offer the desired corrosion resistance. For experiments to test the conjecture, thin alloy films containing various proportions of nickel and zirconium were deposited by magnetron and radiofrequency co-sputtering of nickel and zirconium. The results of x-ray diffraction studies of the deposited films suggested that the films had a nanophase and nearly amorphous character.

Narayanan, Sekharipuram; Whitacre, jay; Valdez, Thomas

2008-01-01

173

The redistribution of impurities in zirconium at cyclic hydrogenation  

Microsoft Academic Search

The effect of dehydrogenation process temperature on the peculiarities of electronegative impurities redistribution in the volu me and on the surface of zirconium have been studied by kinetic method and Auger electron spectroscopy. The influence of hydrogenation and dehydrogenation processes on the density of electronic charge on 57Fe nucleus in Zr2Fe compound have been examined by method of nuclear ?-

D. V. Schur

174

Synthesis and Liquid Crystal Phase Transitions of Zirconium Phosphate Disks  

E-print Network

-shaped nanoparticles, and use it for the study of self-assembly and discotic liquid crystal phase transitions of discotic particles. The work was introduced by the control over the size and polydispersity of zirconium phosphate (ZrP) disks through synthesis...

Shuai, Min

2013-05-07

175

Mo-98(p,d)mo-97 Reaction and Core Coupling in Mo-97 and Nb-97  

E-print Network

REACTIONS, NUCLEAR STRUCTURE ' Mo(P, d), E=3S.6 Mev; measured o'(&), 97Mo levels; deduced l, S; calculated J, 7(', S, particle-core- coupling model, Q for 9 Mo (2+) and 9 Mo (g.s.), &{E2), &(M1) for 97Mo, ~Nb. I. INTRODUCTION Recently we have studied... of dissociation of phonons into particle-hole pairs will be incl.uded. ~ The level structure of 97Mo has been cal,culated by Vervier" and by Choudhury and Cl.emens, ' Vervier uses the effective mutual interaction of the nUcleon8 in the p(2Pg~g) w(lgegg) p(2...

Bindal, P. K.; Youngblood, David H.; Kozub, R. L.; Hoffmannpinther, P. H.

1975-01-01

176

The application and comparison of 97Zr and 92Sr in the absolute determination of the contribution of power density and cladding activation in a VVER-1000 Mock-Up on the LR-0 Research Reactor  

NASA Astrophysics Data System (ADS)

97Zr is a relatively high-yield fission product that can be used for zero reactor power determination. The technique is not widely used because in the case of reactors that use zirconium metal in the fuel cladding, it is not only a fission product but is also produced by activation. In an appropriately chosen time interval, results obtained using 97Zr can be compared to those of power determination performed using 92Sr. The knowledge of the ratio between fission-induced 97Zr and the portion of 97Zr activated in the cladding can be used not only for power-density determination but also as an important indication of fuel failures.

Koš?ál, Michal; Švadlenková, Marie; Mil?ák, Ján

2014-02-01

177

ISRP REPORT 97-2 15 August, 1997 1  

E-print Network

ISRP REPORT 97-2 15 August, 1997 1 Council document ISRP 97-2 Report of the Independent Scientific. Riddell Jack A. Stanford Susan S. Hanna ISRP Report 97- 2 15 August, 1997 #12;ISRP REPORT 97-2 15 August...........................................................................................................................................................10 #12;ISRP REPORT 97-2 15 August, 1997 3 EXECUTIVE SUMMARY The ISRP believes the proposed criteria

178

47 CFR 97.217 - Telemetry.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.217 Telemetry. Telemetry transmitted by an amateur station on or within 50 km of the...

2012-10-01

179

47 CFR 97.209 - Earth station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class...

2013-10-01

180

47 CFR 97.205 - Repeater station.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician,...

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47 CFR 97.217 - Telemetry.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.217 Telemetry. Telemetry transmitted by an amateur station on or within 50 km of the...

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47 CFR 97.205 - Repeater station.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician,...

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47 CFR 97.201 - Auxiliary station.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.201 Auxiliary station. (a) Any amateur station licensed to a holder of a Technician,...

2011-10-01

184

47 CFR 97.205 - Repeater station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician,...

2013-10-01

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47 CFR 97.209 - Earth station.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class...

2011-10-01

186

47 CFR 97.205 - Repeater station.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician,...

2011-10-01

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47 CFR 97.217 - Telemetry.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.217 Telemetry. Telemetry transmitted by an amateur station on or within 50 km of the...

2013-10-01

188

47 CFR 97.201 - Auxiliary station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.201 Auxiliary station. (a) Any amateur station licensed to a holder of a Technician,...

2013-10-01

189

47 CFR 97.201 - Auxiliary station.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.201 Auxiliary station. (a) Any amateur station licensed to a holder of a Technician,...

2010-10-01

190

47 CFR 97.209 - Earth station.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.209 Earth station. (a) Any amateur station may be an Earth station. A holder of any class...

2012-10-01

191

47 CFR 97.201 - Auxiliary station.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.201 Auxiliary station. (a) Any amateur station licensed to a holder of a Technician,...

2012-10-01

192

47 CFR 97.217 - Telemetry.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.217 Telemetry. Telemetry transmitted by an amateur station on or within 50 km of the...

2011-10-01

193

47 CFR 97.117 - International communications.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.117 ...be limited to communications incidental to the purposes of the amateur service and to remarks of a personal character. [71...

2012-10-01

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47 CFR 97.117 - International communications.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.117 ...be limited to communications incidental to the purposes of the amateur service and to remarks of a personal character. [71...

2010-10-01

195

47 CFR 97.25 - License term.  

Code of Federal Regulations, 2012 CFR

...FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.25 License term. An amateur service license is normally granted for a 10-year term. [63 FR 68979,...

2012-10-01

196

47 CFR 97.117 - International communications.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.117 ...be limited to communications incidental to the purposes of the amateur service and to remarks of a personal character. [71...

2011-10-01

197

47 CFR 97.109 - Station control.  

Code of Federal Regulations, 2013 CFR

...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.109 Station control. (a) Each amateur station must have at least one control point. (b) When a...

2013-10-01

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47 CFR 97.25 - License term.  

Code of Federal Regulations, 2013 CFR

...FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.25 License term. An amateur service license is normally granted for a 10-year term. [63 FR 68979,...

2013-10-01

199

47 CFR 97.109 - Station control.  

Code of Federal Regulations, 2011 CFR

...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.109 Station control. (a) Each amateur station must have at least one control point. (b) When a...

2011-10-01

200

47 CFR 97.117 - International communications.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.117 ...be limited to communications incidental to the purposes of the amateur service and to remarks of a personal character. [71...

2013-10-01

201

47 CFR 97.23 - Mailing address.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.23 Mailing address...mailing address. The mailing address must be in an area where the amateur service is regulated by the FCC and where the...

2012-10-01

202

47 CFR 97.25 - License term.  

Code of Federal Regulations, 2010 CFR

...FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.25 License term. An amateur service license is normally granted for a 10-year term. [63 FR 68979,...

2010-10-01

203

47 CFR 97.23 - Mailing address.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.23 Mailing address...mailing address. The mailing address must be in an area where the amateur service is regulated by the FCC and where the...

2010-10-01

204

47 CFR 97.23 - Mailing address.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.23 Mailing address...mailing address. The mailing address must be in an area where the amateur service is regulated by the FCC and where the...

2011-10-01

205

47 CFR 97.109 - Station control.  

Code of Federal Regulations, 2012 CFR

...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.109 Station control. (a) Each amateur station must have at least one control point. (b) When a...

2012-10-01

206

47 CFR 97.25 - License term.  

Code of Federal Regulations, 2011 CFR

...FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.25 License term. An amateur service license is normally granted for a 10-year term. [63 FR 68979,...

2011-10-01

207

47 CFR 97.23 - Mailing address.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.23 Mailing address...mailing address. The mailing address must be in an area where the amateur service is regulated by the FCC and where the...

2013-10-01

208

50 CFR 300.97 - Inseason orders.  

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2014-10-01

209

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2013 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2013-10-01

210

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2011 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2011-10-01

211

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2012 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2012-10-01

212

50 CFR 300.97 - Inseason orders.  

Code of Federal Regulations, 2010 CFR

...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

2010-10-01

213

34 CFR 97.114 - Cooperative research.  

Code of Federal Regulations, 2010 CFR

34 Education 1 2010-07-01...114 Section 97.114 Education Office of the Secretary, Department of Education PROTECTION OF HUMAN SUBJECTS Federal Policy...responsible for safeguarding the rights and welfare of...

2010-07-01

214

32 CFR 9.7 - Regulations.  

Code of Federal Regulations, 2010 CFR

...MILITARY COMMISSIONS PROCEDURES FOR TRIALS BY MILITARY COMMISSIONS OF CERTAIN NON-UNITED STATES CITIZENS IN THE WAR AGAINST TERRORISM § 9.7 Regulations. (a) Supplementary regulations and instructions. The Appointing Authority...

2010-07-01

215

29 CFR 97.31 - Real property.  

Code of Federal Regulations, 2012 CFR

29 Labor 1 2012-07-01...31 Section 97.31 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...purchase to the fair market value of the...

2012-07-01

216

29 CFR 97.33 - Supplies.  

29 Labor 1 2014-07-01...33 Section 97.33 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...total aggregate fair market value upon...

2014-07-01

217

29 CFR 97.32 - Equipment.  

Code of Federal Regulations, 2012 CFR

29 Labor 1 2012-07-01...32 Section 97.32 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...current per-unit fair market value of less...

2012-07-01

218

29 CFR 97.32 - Equipment.  

Code of Federal Regulations, 2011 CFR

29 Labor 1 2011-07-01...32 Section 97.32 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...current per-unit fair market value of less...

2011-07-01

219

29 CFR 97.33 - Supplies.  

Code of Federal Regulations, 2010 CFR

29 Labor 1 2010-07-01...33 Section 97.33 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...total aggregate fair market value upon...

2010-07-01

220

29 CFR 97.32 - Equipment.  

Code of Federal Regulations, 2010 CFR

29 Labor 1 2010-07-01...32 Section 97.32 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...current per-unit fair market value of less...

2010-07-01

221

29 CFR 97.32 - Equipment.  

Code of Federal Regulations, 2013 CFR

29 Labor 1 2013-07-01...32 Section 97.32 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...current per-unit fair market value of less...

2013-07-01

222

29 CFR 97.33 - Supplies.  

Code of Federal Regulations, 2013 CFR

29 Labor 1 2013-07-01...33 Section 97.33 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...total aggregate fair market value upon...

2013-07-01

223

29 CFR 97.31 - Real property.  

Code of Federal Regulations, 2011 CFR

29 Labor 1 2011-07-01...31 Section 97.31 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...purchase to the fair market value of the...

2011-07-01

224

29 CFR 97.31 - Real property.  

Code of Federal Regulations, 2010 CFR

29 Labor 1 2010-07-01...31 Section 97.31 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...purchase to the fair market value of the...

2010-07-01

225

29 CFR 97.33 - Supplies.  

Code of Federal Regulations, 2011 CFR

29 Labor 1 2011-07-01...33 Section 97.33 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...total aggregate fair market value upon...

2011-07-01

226

29 CFR 97.32 - Equipment.  

29 Labor 1 2014-07-01...32 Section 97.32 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...current per-unit fair market value of less...

2014-07-01

227

29 CFR 97.31 - Real property.  

29 Labor 1 2014-07-01...31 Section 97.31 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...purchase to the fair market value of the...

2014-07-01

228

29 CFR 97.31 - Real property.  

Code of Federal Regulations, 2013 CFR

29 Labor 1 2013-07-01...31 Section 97.31 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...purchase to the fair market value of the...

2013-07-01

229

29 CFR 97.33 - Supplies.  

Code of Federal Regulations, 2012 CFR

29 Labor 1 2012-07-01...33 Section 97.33 Labor Office of the Secretary of Labor UNIFORM ADMINISTRATIVE...Post-Award Requirements Changes, Property, and Subawards...total aggregate fair market value upon...

2012-07-01

230

The p97-FAF1 Protein Complex Reveals a Common Mode of p97 Adaptor Binding*  

PubMed Central

p97, also known as valosin-containing protein, is a versatile participant in the ubiquitin-proteasome system. p97 interacts with a large network of adaptor proteins to process ubiquitylated substrates in different cellular pathways, including endoplasmic reticulum-associated degradation and transcription factor activation. p97 and its adaptor Fas-associated factor-1 (FAF1) both have roles in the ubiquitin-proteasome system during NF-?B activation, although the mechanisms are unknown. FAF1 itself also has emerging roles in other cell-cycle pathways and displays altered expression levels in various cancer cell lines. We have performed a detailed study the p97-FAF1 interaction. We show that FAF1 binds p97 stably and in a stoichiometry of 3 to 6. Cryo-EM analysis of p97-FAF1 yielded a 17 ? reconstruction of the complex with FAF1 above the p97 ring. Characteristics of p97-FAF1 uncovered in this study reveal common features in the interactions of p97, providing mechanistic insight into how p97 mediates diverse functionalities. PMID:24619421

Ewens, Caroline A.; Panico, Silvia; Kloppsteck, Patrik; McKeown, Ciaran; Ebong, Ima-Obong; Robinson, Carol; Zhang, Xiaodong; Freemont, Paul S.

2014-01-01

231

The p97-FAF1 protein complex reveals a common mode of p97 adaptor binding.  

PubMed

p97, also known as valosin-containing protein, is a versatile participant in the ubiquitin-proteasome system. p97 interacts with a large network of adaptor proteins to process ubiquitylated substrates in different cellular pathways, including endoplasmic reticulum-associated degradation and transcription factor activation. p97 and its adaptor Fas-associated factor-1 (FAF1) both have roles in the ubiquitin-proteasome system during NF-?B activation, although the mechanisms are unknown. FAF1 itself also has emerging roles in other cell-cycle pathways and displays altered expression levels in various cancer cell lines. We have performed a detailed study the p97-FAF1 interaction. We show that FAF1 binds p97 stably and in a stoichiometry of 3 to 6. Cryo-EM analysis of p97-FAF1 yielded a 17 ? reconstruction of the complex with FAF1 above the p97 ring. Characteristics of p97-FAF1 uncovered in this study reveal common features in the interactions of p97, providing mechanistic insight into how p97 mediates diverse functionalities. PMID:24619421

Ewens, Caroline A; Panico, Silvia; Kloppsteck, Patrik; McKeown, Ciaran; Ebong, Ima-Obong; Robinson, Carol; Zhang, Xiaodong; Freemont, Paul S

2014-04-25

232

Nuclear-grade zirconium prepared by combining combustion synthesis with molten-salt electrorefining technique  

NASA Astrophysics Data System (ADS)

Zirconium has a low absorption cross-section for neutrons, which makes it an ideal material for use in nuclear reactor applications. However, hafnium typically contained in zirconium causes it to be far less useful for nuclear reactor materials because of its high neutron-absorbing properties. In the present study, a novel effective method has been developed for the production of hafnium-free zirconium. The process includes two main stages: magnesio-thermic reduction of ZrSiO 4 under a combustion mode, to produce zirconium silicide (ZrSi), and recovery of hafnium-free zirconium by molten-salt electrorefining. It was found that, depending on the electrorefining procedure, it is possible to produce zirconium powder with a low hafnium content: 70 ppm, determined by ICP-AES analysis.

Li, Hui; Nersisyan, Hayk H.; Park, Kyung-Tae; Park, Sung-Bin; Kim, Jeong-Guk; Lee, Jeong-Min; Lee, Jong-Hyeon

2011-06-01

233

7 CFR 97.104 - Application or certificate abandoned.  

Code of Federal Regulations, 2011 CFR

... false Application or certificate abandoned. 97.104 Section 97.104 Agriculture...97.104 Application or certificate abandoned. (a) Except as provided in paragraph...the application shall be considered abandoned. (b) Upon request by the...

2011-01-01

234

7 CFR 97.104 - Application or certificate abandoned.  

Code of Federal Regulations, 2013 CFR

... false Application or certificate abandoned. 97.104 Section 97.104 Agriculture...97.104 Application or certificate abandoned. (a) Except as provided in paragraph...the application shall be considered abandoned. (b) Upon request by the...

2013-01-01

235

7 CFR 97.104 - Application or certificate abandoned.  

Code of Federal Regulations, 2012 CFR

... false Application or certificate abandoned. 97.104 Section 97.104 Agriculture...97.104 Application or certificate abandoned. (a) Except as provided in paragraph...the application shall be considered abandoned. (b) Upon request by the...

2012-01-01

236

7 CFR 97.104 - Application or certificate abandoned.  

... false Application or certificate abandoned. 97.104 Section 97.104 Agriculture...97.104 Application or certificate abandoned. (a) Except as provided in paragraph...the application shall be considered abandoned. (b) Upon request by the...

2014-01-01

237

7 CFR 97.104 - Application or certificate abandoned.  

Code of Federal Regulations, 2010 CFR

... false Application or certificate abandoned. 97.104 Section 97.104 Agriculture...97.104 Application or certificate abandoned. (a) Except as provided in paragraph...the application shall be considered abandoned. (b) Upon request by the...

2010-01-01

238

47 CFR Appendix 2 to Part 97 - VEC Regions  

Code of Federal Regulations, 2010 CFR

...Appendix 2 to Part 97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Pt. 97, App. 2 Appendix 2 to Part 97—VEC Regions 1. Connecticut, Maine, Massachusetts, New...

2010-10-01

239

47 CFR Appendix 2 to Part 97 - VEC Regions  

Code of Federal Regulations, 2011 CFR

...Appendix 2 to Part 97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Pt. 97, App. 2 Appendix 2 to Part 97—VEC Regions 1. Connecticut, Maine, Massachusetts, New...

2011-10-01

240

47 CFR Appendix 2 to Part 97 - VEC Regions  

Code of Federal Regulations, 2013 CFR

...Appendix 2 to Part 97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Pt. 97, App. 2 Appendix 2 to Part 97—VEC Regions 1. Connecticut, Maine, Massachusetts, New...

2013-10-01

241

47 CFR Appendix 2 to Part 97 - VEC Regions  

Code of Federal Regulations, 2012 CFR

...Appendix 2 to Part 97 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Pt. 97, App. 2 Appendix 2 to Part 97—VEC Regions 1. Connecticut, Maine, Massachusetts, New...

2012-10-01

242

47 CFR 97.115 - Third party communications.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Third party communications. 97.115 Section 97.115 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...Standards § 97.115 Third party communications. (a) An amateur...

2010-10-01

243

27 CFR 24.97 - Use on premises.  

Code of Federal Regulations, 2010 CFR

27 Alcohol, Tobacco Products and Firearms 1...premises. 24.97 Section 24.97 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU...24.97 Use on premises. (a) Analysis or testing. The proprietor...

2010-04-01

244

27 CFR 24.97 - Use on premises.  

Code of Federal Regulations, 2011 CFR

27 Alcohol, Tobacco Products and Firearms 1...premises. 24.97 Section 24.97 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU...24.97 Use on premises. (a) Analysis or testing. The proprietor...

2011-04-01

245

27 CFR 24.97 - Use on premises.  

Code of Federal Regulations, 2012 CFR

27 Alcohol, Tobacco Products and Firearms 1...premises. 24.97 Section 24.97 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU...24.97 Use on premises. (a) Analysis or testing. The proprietor...

2012-04-01

246

40 CFR 97.13 - Account certificate of representation.  

Code of Federal Regulations, 2013 CFR

... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

2013-07-01

247

40 CFR 97.13 - Account certificate of representation.  

Code of Federal Regulations, 2012 CFR

... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

2012-07-01

248

40 CFR 97.13 - Account certificate of representation.  

Code of Federal Regulations, 2011 CFR

... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

2011-07-01

249

40 CFR 97.13 - Account certificate of representation.  

Code of Federal Regulations, 2010 CFR

... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

2010-07-01

250

40 CFR 97.13 - Account certificate of representation.  

... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

2014-07-01

251

34 CFR 97.117 - Documentation of informed consent.  

...2014-07-01 false Documentation of informed consent. 97.117 Section 97...97.117 Documentation of informed consent. (a) Except as provided...paragraph (c) of this section, informed consent shall be documented by the...

2014-07-01

252

34 CFR 97.117 - Documentation of informed consent.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Documentation of informed consent. 97.117 Section 97...97.117 Documentation of informed consent. (a) Except as provided...paragraph (c) of this section, informed consent shall be documented by the...

2011-07-01

253

34 CFR 97.117 - Documentation of informed consent.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Documentation of informed consent. 97.117 Section 97...97.117 Documentation of informed consent. (a) Except as provided...paragraph (c) of this section, informed consent shall be documented by the...

2012-07-01

254

34 CFR 97.117 - Documentation of informed consent.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Documentation of informed consent. 97.117 Section 97...97.117 Documentation of informed consent. (a) Except as provided...paragraph (c) of this section, informed consent shall be documented by the...

2010-07-01

255

34 CFR 97.117 - Documentation of informed consent.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Documentation of informed consent. 97.117 Section 97...97.117 Documentation of informed consent. (a) Except as provided...paragraph (c) of this section, informed consent shall be documented by the...

2013-07-01

256

34 CFR 97.109 - IRB review of research.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

2010-07-01

257

34 CFR 97.109 - IRB review of research.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

2011-07-01

258

Complexation Chemistry of Zirconium(IV), Uranium(VI), and Iron(III) with Acetohydroxamic Acid  

Microsoft Academic Search

The complexation of zirconium(IV), uranium(VI), and iron(III) with acetohydroxamic acid (AHA) has been analyzed spectrophotometrically in various ionic strengths at 25°C. Arsenazo III (AAIII) was used as an indicator for unbound zirconium. The SQUAD computational program was employed to evaluate the stability constants. Conditional stability constants of four zirconium complexes Zr(AAIII), , Zr(AHA), and were determined in 1 mol · L HClO4 as

Brent S. Matteson; Peter Tkac; Alena Paulenova

2010-01-01

259

Alternative Processing of High Temperature Hafnium and Zirconium Based Materials  

NASA Technical Reports Server (NTRS)

The behavior of refractory hafnium and zirconium based materials are being investigated at NASA Ames as part of ongoing research aimed at developing superior heat resistant materials for aerospace applications. Hafnium and zirconium diboride based materials have shown high temperature capabilities in simulated reentry environments indicating that these materials may successfully operate as reusable oxidation resistant components for leading edge applications. Due to the refractory nature of these materials, processing of fine-grained uniform microstructures poses a number of challenges. To better understand the process-property-microstructure relationship, processing of these materials has been carried out with conventional hot pressing in addition to the novel approach of Spark Plasma Sintering (SPS). The two processing methods are compared and contrasted in an evaluation of the sintering behavior of high temperature diboride based materials and preliminary physical and mechanical properties are presented.

Gasch, Matthew; Gusman, Michael; Ellerby, Don; Irby, Edward; Johnson, Sylvia M.

2003-01-01

260

Computer simulation of displacement cascades in {alpha}-zirconium  

SciTech Connect

The damage produced in {alpha}-zirconium at 100 K by displacement cascades with energy up to 20 keV has been investigated by MD simulations. In agreement with modelling of fcc and bcc metals, the defect production efficiency in zirconium is well below the NRT estimate. The number and size of clusters, both vacancy and interstitial, are increased by increasing PKA energy, and clusters containing up to 25 interstitials and 30 vacancies were formed by 20 keV cascades. Most interstitial clusters have dislocation character with perfect Burgers vectors of the form 1/3<11{bar 2}0>, but a few metastable clusters are formed and are persistent over the timescale of MD simulations. Collapse of the 30-vacancy cluster to a faulted loop on the prism plane was found to occur over a period of more than 100 ps.

Gao, F.; Wooding, S.J.; Bacon, D.J.; Calder, A.F. [Univ. of Liverpool (United Kingdom). Dept. of Materials Science and Engineering; Howe, L.M. [AECL Chalk River Labs., Ontario (Canada)

1997-11-01

261

Modelling zirconium hydrides using the special quasirandom structure approach.  

PubMed

The study of the structure and properties of zirconium hydrides is important for understanding the embrittlement of zirconium alloys used as cladding in light water nuclear reactors. Simulation of the defect processes is complicated due to the random distribution of the hydrogen atoms. We propose the use of the special quasirandom structure approach as a computationally efficient way to describe this random distribution. We have generated six special quasirandom structure cells based on face centered cubic and face centered tetragonal unit cells to describe ZrH(2-x) (x = 0.25-0.5). Using density functional theory calculations we investigate the mechanical properties, stability, and electronic structure of the alloys. PMID:23588997

Wang, H; Chroneos, A; Jiang, C; Schwingenschlögl, U

2013-05-28

262

Radioactivity in zirconium oxide powders used in industrial applications.  

PubMed

Recent work involving the decommissioning of a former ceramic manufacturing facility licensed by the Nuclear Regulatory Commission for activities involving depleted uranium oxide has uncovered the presence of unexpected high levels of natural radioactivity in non-licensed zirconium oxide powders also used in the same facility. A comparison between the levels of source material found in samples of this material and the current regulatory guidance for licensed activities and decommissioning has been conducted. It has been determined that the radioactivity in the zirconium oxide is of a high enough magnitude to raise health physics concerns in the areas of licensing and regulatory compliance, decontamination criteria, and worker health and safety. An examination of these areas has been conducted and the implications associated with our findings are presented. PMID:2032840

Lischinsky, J; Vigliani, M A; Allard, D J

1991-06-01

263

Effects of solutes on damage production and recovery in zirconium  

SciTech Connect

Dilute zirconium-based alloys and pure zirconium were irradiated at 10 K with spallation neutrons at IPNS. Four types of alloys - Zr-Ti, Zr-Sn, Zr-Dy and Zr-Au - each with three concentration levels, were used. Low-temperature resistivity damage rates are enhanced by the presence of any of the four solutes. The greatest enhancement was produced by Au while the least by Dy. Within each alloy group, damage production also increased but at a decreasing rate, with increasing concentration. Post-irradiation annealing experiments, up to 400 K, showed that all four solutes suppress recovery due to interstitial migration, indicative of interstitial trapping by the solutes. Vacancy recovery is also suppressed by the presence of Sn, Dy or Au. The effect of Ti is to shift this stage to lower temperature. No clear correlation between the results with solute size was detected.

Zee, R.H.; Birtcher, R.C.; MacEwen, S.R.; Abromeit, C.

1986-04-01

264

Corrosion behavior of stainless steel-zirconium alloy waste forms  

SciTech Connect

Stainless steel-zirconium (SS-Zr) alloys are being considered as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The baseline waste form for spent fuels from the EBR-11 reactor is a stainless steel-15 wt.% zirconium (SS-15Zr) alloy. This article briefly reviews the microstructure of various SS-Zr waste form alloys and presents results of immersion corrosion and electrochemical corrosion tests performed on these alloys. The electrochemical tests show that the corrosion behavior of SS-Zr alloys is comparable to those of other alloys being considered for the Yucca Mountain geologic repository. The immersion tests demonstrate that the SS-Zr alloys are resistant to selective leaching of fission product elements and, hence, suitable as candidates for high-level nuclear waste forms.

Abraham, D.P.; Simpson, L.J.; DeVries, M.J.; Callahan, D.E.

1999-07-01

265

Corrosion testing of stainless steel-zirconium metal waste forms  

SciTech Connect

Stainless steel-zirconium (SS-Zr) alloys have been developed as waste forms for the disposal of metallic waste generated during the electrometallurgical treatment of spent nuclear fuel. The waste forms incorporate irradiated cladding hulls, components of the alloy fuel, noble metal fission products, and actinide elements. The baseline waste form is a stainless steel-15 wt% zirconium (SS-15Zr) alloy. This article presents microstructures and some of the corrosion studies being conducted on the waste form alloys. Electrochemical corrosion, immersion corrosion, and vapor hydration tests have been performed on various alloy compositions to evaluate corrosion behavior and resistance to selective leaching of simulated fission products. The SS-Zr waste forms immobilize and retain fission products very effectively and show potential for acceptance as high-level nuclear waste forms.

Abraham, D.P.; Simpson, L.J.; Devries, M.J.; McDeavitt, S.M.

1999-07-01

266

40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.  

Code of Federal Regulations, 2010 CFR

...PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the...

2010-07-01

267

Synthesis and analytical application of tribromocarboxyarsenazo as a new chromogenic reagent for zirconium.  

PubMed

A new chromogenic reagent tribromocarboxyarsenazo has been synthesized and the chromogenic reaction of this reagent with zirconium studied. In the medium of 0.5 mol/1 HCl, a blue complex is formed by the reaction of zirconium with tribromocarboxyarsenazo. The maximum absorption of the complex is at 633 nm, and the apparent molar absorptivity is 4.8 x 10(4) 1/mol/cm. Beer's law is obeyed over the zirconium concentration range 0-18, mug/25 ml. The method has been applied to the determination of zirconium in aluminum, copper and magnesium alloys with satisfactory results. PMID:18965981

Yang, H Y; Zhang, H S; Wang, H

1994-05-01

268

Studies of microstructural imperfections of powdered Zirconium-based alloys  

SciTech Connect

Different model based approaches of X-ray diffraction line profile analysis have been applied on the heavily deformed zirconium-based alloys in the powdered form to characterize the microstructural parameters like domain size, microstrain and dislocation density. In characterizing the microstructure of the material, these methods are complimentary to each other. Though the parameters obtained by different techniques are differently defined and thus not necessarily comparable, the values of domain size and microstrain obtained from the different techniques show similar trends.

Chowdhury, P.S. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata-700 064 (India); Sarkar, A. [Mechanical Metallurgy Section, Bhabha Atomic Research Centre, Mumbai-400085 (India); Mukherjee, P., E-mail: paramita@vecc.gov.in [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata-700 064 (India); Gayathri, N.; Bhattacharya, M.; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata-700 064 (India)

2010-11-15

269

Influence of Temperature on the Dynamic Tensile Behavior of Zirconium  

NASA Astrophysics Data System (ADS)

The influence of temperature on the dynamic tensile behavior of Zr has been investigated. Bullet-shaped Zr samples with two different textures were dynamically extruded at room temperature and 523 K (250 °C). A higher ductility was measured for samples deformed at elevated temperature as compared to those extruded at room temperature. This difference in ductility is discussed in terms of zirconium's ability to accommodate plastic deformation via thermally enhanced slip activity, as evidenced by examination of the deformed microstructures.

Escobedo, Juan P.; Cerreta, Ellen K.; Martinez, Daniel T.; Trujillo, Carl P.; Lebensohn, Ricardo A.; Gray, George T.

2014-12-01

270

Sintering behavior in zirconium phosphate bonded silicon nitride porous ceramics  

Microsoft Academic Search

A new method for preparing high bending strength porous silicon nitride ceramics with controlled porosity has been developed by using a pressureless sintering technique with zirconium phosphate (ZrP2O7) as a binder phase. The sintering behavior in these porous ceramics is investigated in this study by using XRD, SEM, and HRTEM analysis. The results show that the sintering process can be

Fei Chen; Qiang Shen; Julie M. Schoenung; Lianmeng Zhang

2008-01-01

271

The abundances of zirconium and hafnium in the solar system  

Microsoft Academic Search

The concentrations of zirconium and hafnium have been determined in the Orgueil, Murchison, Allende, Bruderheim, and Alais meteorites by radiochemical neutron activation analysis. The mean Zr\\/Hf weight ratio in the first four of these meteorites is 31.3 (plus or minus 2.2), indicating no major fractionation of Zr from Hf. Alais contains anomalously high amounts of many refractory lithophile elements, including

R. Ganapathy; G. M. Papia; LAWRENCE GROSSMAN

1976-01-01

272

Spectrum of Five Times Ionized Zirconium (Zr VI)  

Microsoft Academic Search

We report 279 newly identified transitions of five times ionized zirconium atom (Zr VI) based on recordings made at the 3 m normal incidence spectrograph of Lund University. Thirty-three new energy levels have been established, comprising all the twenty-one levels of 5p configuration, all the nine of 4d that were not known so far, and three of 7s. Previously reported

Zainul Abedeen Khan; M. S. Z. Chaghtai; K. Rahimullah

1981-01-01

273

Trivalent zirconium and hafnium ions in yttrium oxide ceramics  

NASA Astrophysics Data System (ADS)

An analysis of the electron spin resonance (ESR) spectrum of transparent ceramics composed of yttrium oxide with zirconium and hafnium additives has revealed the presence of signals (with similar parameters) from Zr3+ and Hf3+ ions, which have a similar electron configurations of the ground states: [Kr]4 d 1 and [Xe]5 d 1, respectively. It is shown that the pulsed cathodoluminescence spectra of these ions consist of two bands peaking at ? ? 818 and 900 nm.

Solomonov, V. I.; Spirina, A. V.; Konev, S. F.; Cholakh, S. O.

2014-05-01

274

Properties of silicon — Manganese steel with vanadium and zirconium  

Microsoft Academic Search

1.Steel 36G2S with concentrations of carbon and manganese at the lower limit of the range specified does not satisfy the requi rements for the mechanical properties of steel of strength group K for casting pipe (GQST 632-64).2.The addition of small amounts of vanadium and zirconium to medium-carbon silicon-manganese steel increases the strength and ductile characteristics of the steel and ensures

V. N. Zikeev; B. P. Kolesnik; D. A. Litvinenko; V. T. Ababkov; L. I. Guzevataya

1969-01-01

275

Diffusion of Aluminum, Magnesium, Silicon and Zirconium in Nickel  

Microsoft Academic Search

The diffusion rates of aluminum, magnesium, silicon, and zirconium, alloyed as single additives in nickel, have been measured at temperatures between 800°C and 970°C. The method consisted of measuring the weight gain caused by surface oxidation of the additive in a wet hydrogen ambient. The surface oxides were identified by electron diffraction. Grain size was about 0.05 mm in Al&sngbnd;Ni,

Herbert W. Allison; Harold Samelson

1959-01-01

276

A strong ceramic based on aluminum oxide and zirconium dioxide  

Microsoft Academic Search

The theoretical premises and experimental results on fabrication of ceramics based on aluminum oxide with a regulatable structure\\u000a which ensures high strength properties and the possibility of wide use in different areas of technology were reported. The\\u000a effect of adding zirconium oxide to aluminum oxide on the structure and strength properties of the ceramics was demonstrated.\\u000a New ceramic materials having

E. S. Lukin; N. A. Popova; N. I. Zdvizhkova

1993-01-01

277

Polyimide nanocomposites based on cubic zirconium tungstate  

NASA Astrophysics Data System (ADS)

In this research, cubic zirconium tungstate (ZrW2O8) was used as a filler to reduce the CTE of polyimides (PI), and the effect of ZrW2O8 nanoparticles on the bulk polymer properties was studied. Polyimides are high performance polymers with exceptional thermal stability, and there is a need for PIs with low CTEs for high temperature applications. The nanofiller, cubic ZrW2O8, is well known for its isotropic negative thermal expansion (NTE) over a wide temperature range from -272.7 to 777°C. The preparation of nanocomposites involved the synthesis of ZrW 2O8 nanofiller, engineering the polymer-filler interface using linker groups and optimization of processing strategies to prepare free-standing PI nanocomposite films. A hydrothermal method was used to synthesize ZrW 2O8 nanoparticles. Polyimide-ZrW2O8 interface interaction was enhanced by covalently bonding linker moieties to the surface of ZrW2O8 nanoparticles. Specifically, ZrW 2O8 nanoparticles were functionalized with two different linker groups: (1) a short aliphatic silane, and (2) low molecular weight PI. The surface functionalization was confirmed using X-ray photoelectron spectroscopy and thermal gravimetric analysis (TGA). Reprecipitation blending was used to prepare the freestanding PI-ZrW2O8 nanocomposite films with up to 15 volume% filler loading. SEM images showed the improvements in polymer-filler wetting behavior achieved using interface engineering. SEM images indicated that there was better filler dispersion in the PI matrix using reprecipitation blending, compared to the filler dispersion achieved in the nanocomposites prepared using conventional blending technique. The structure-property relationships in PI-ZrW2O8 nanocomposites were investigated by studying the thermal degradation, glass transition, tensile and thermal expansion properties of the nanocomposites. The properties were studied as a function of filler loading and interface linker groups. Addition of ZrW2O8 nanoparticles did not alter the thermal degradation and glass transition temperatures of the base PI. The addition of ZrW2O8 nanoparticles increased the Young's modulus of the polymer, indicating the stiffening of polyimide matrix. The modulus showed a steady increase with increase in filler loading. The increase was higher for nanocomposites with engineered interface due to the efficient load transfer achieved through the presence of linker groups. The strain at yield and the tensile strength decreased with the addition of ZrW2O8. The experimental results for the moduli of nanocomposites were compared with moduli predicted using theoretical models. The results for the nanocomposites with unmodified ZrW2O8 followed Hashin-Shtrikman (H-S) lower bound, which showed the presence of mechanical interactions between the polymer and filler. The moduli for nanocomposites with engineered interface fell between the H-S bounds, demonstrating the stiffening of PI matrix through efficient load transfer. The addition of ZrW2O8 reduced the in-plane CTE of the base PI at all loadings. The CTE of the nanocomposites decreased steadily with an increase in the filler loading. With the addition of 15 volume% APT-ZrW 2O8, the CTE of the base PI reduced from 64.3 +/- 1.3 ppm/°C to 51.9 +/- 0.9 ppm/°C. In other words, the CTE of the base PI was reduced by around 22% with the addition of ZrW2O 8 at 15 volume% loading. The CTE values were comparable for all samples at similar loadings irrespective of the interface groups. The experimental results for the CTEs of nanocomposites were compared with CTEs predicted using theoretical models. The data followed the Schapery upper bound, which was consistent with the results observed for the moduli data. The effect of ZrW2O8 particle size on the bulk properties of the polyimide was also investigated. The CTE of composites with micron particles at 5 volume% was comparable to that obtained for nanocomposites at the same filler loading. But, there were significant differences in the mechanical strength of composites. PI composites with ZrW2O 8 micron particles were extre

Ramasubramanian Sharma, Gayathri

2009-12-01

278

NASA/CR-97-206268 ICASE Report No. 97-68  

E-print Network

NASA/CR-97-206268 ICASE Report No. 97-68 _th ,NNIVERSARY Essential Elements of Computational Algorithms for Aerodynamic Analysis and Design Antony Jameson December 1997 #12;The NASA STI Program Off'we... in Profile Since its founding, NASA has been dedicated to the advancement of aeronautics and space science

Jameson, Antony

279

40 CFR 97.211 - Alternate CAIR designated representative.  

Code of Federal Regulations, 2010 CFR

...212, 97.213, 97.215, 97.251 and 97.282, whenever the term “CAIR designated representative” is used in subparts AAA through III of this part, the term shall be construed to include the CAIR designated representative or any alternate CAIR...

2010-07-01

280

Materials Science and Engineering A334 (2002) 610 Simulation of g-hydride precipitation in bi-crystalline zirconium  

E-print Network

hot water environment. Zirconium will gradually pick up hydrogen from the hot water environment during June 2001 Abstract The morphology evolution of g-hydride precipitation and growth in a zirconium bi-crystal Elsevier Science B.V. All rights reserved. Keywords: Computer simulation; Zirconium hydride; Bi-crystal

Chen, Long-Qing

281

Lithium aluminate/zirconium material useful in the production of tritium  

DOEpatents

A composition is described useful in the production of tritium in a nuclear reactor. Lithium aluminate particles are dispersed in a matrix of zirconium. Tritium produced by the reactor of neutrons with the lithium are absorbed by the zirconium, thereby decreasing gas pressure within capsules carrying the material.

Cawley, W.E.; Trapp, T.J.

1984-10-09

282

Removal and recovery of zirconium from its aqueous solution by Candida tropicalis  

Microsoft Academic Search

Removal and recovery of zirconium from dilute aqueous solutions by Candida tropicalis used as biosorbent, was studied by performing biosorption–desorption tests. This biosorbent was selected after screening a range of microbial species. The process was found to be highly dependent on initial pH and concentration of metal solution. At optimized experimental parameters, the maximum zirconium biosorption capacity of C. tropicalis

Kalsoom Akhtar; M. Waheed Akhtar; Ahmad M. Khalid

2008-01-01

283

Formation of a zirconium-titanium based conversion layer on AA 6060 aluminium  

Microsoft Academic Search

Structure and chemistry of zirconium-titanium base conversion layers were characterised as a function of immersion time in the aqueous conversion bath to understand the mechanism of film formation. Characterisation was performed by glow discharge optical emission spectroscopy, scanning electron microscopy and transmission electron microscopy. Preferential nucleation of the zirconium-titanium oxide film and its growth occurred on and around intermetallic particles,

J. H Nordlien; J. C Walmsley; H Østerberg; K Nisancioglu

2002-01-01

284

Zirconium carbide as an electrocatalyst for the chromous-chromic redox couple  

NASA Technical Reports Server (NTRS)

Zirconium carbide is used as a catalyst in a REDOX cell for the oxidation of chromous ions to chromic ions and for the reduction of chromic ions to chromous ions. The zirconium carbide is coated on an inert electronically conductive electrode which is present in the anode fluid of the cell.

Gahn, R. F.; Reid, M. A.; Yang, C. Y. (inventors)

1981-01-01

285

Solid-State Coexistance of (Zr12) and (Zr6) Zirconium Oxocarboxylate Clusters  

SciTech Connect

Ligand metathesis, Co(II) coordination, and partial condensation reactions of an archetypal {Zr6} zirconium oxocarboxylate cluster result in the first example of the coexistence of the distinct zirconium oxide frameworks {Zr6O8} and {Zr12O22}. Even minor modifications to the reaction conditions push this apparent equilibrium towards the {Zr6O8}-based product.

Malaestean, Lurie [RWTH Aachen University; Alici, Meliha Kutluca [RWTH Aachen University; Besson, Claire [RWTH Aachen University; Ellern, Arkady [Ames Laboratory; Kogerler, Paul [RWTH Aachen University

2013-10-30

286

Solid-state coexistence of {Zr12} and {Zr6} zirconium oxocarboxylate clusters  

SciTech Connect

Ligand metathesis, Co(II) coordination, and partial condensation reactions of an archetypal {Zr6} zirconium oxocarboxylate cluster result in the first example of the coexistence of the distinct zirconium oxide frameworks {Zr6O8} and {Zr12O22}. Even minor modifications to the reaction conditions push this apparent equilibrium towards the {Zr6O8}-based product.

Malaestean, Iurie L. [RWTH Aachen University; Alici, Meliha Kutluca [RWTH Aachen University; Besson, Claire [RWTH Aachen University; Ellern, Arkady [Ames Laboratory; Kogerler, Paul [RWTH Aachen University

2013-10-30

287

Corrosion of Zirconium-based Fuel Cladding Alloys in Supercritical Water. Y.H. Jeong1  

E-print Network

Corrosion of Zirconium-based Fuel Cladding Alloys in Supercritical Water. Y.H. Jeong1 , J.Y. Park1, University Park, PA 16802, USA. Keywords: Zirconium alloys, corrosion, supercritical water Abstract Corrosion to evaluate the potential use of Zr alloy cladding in the supercritical water reactor (SCWR). Corrosion tests

Motta, Arthur T.

288

Inorganic ion-exchangers for the removal of zirconium, hafnium and niobium radioisotopes from aqueous solutions  

Microsoft Academic Search

Studies were made on the uptake of zirconium, hafnium and niobium isotopes onto zeolites and amorphous zirconium phosphate. Ion exchange capacities and distribution coefficients were determined and the influence of pH examined. Kinetic experiments were made to determine the rates of uptake of the radioisotopes on the exchangers and to measure the leaching of isotopes from preloaded exchangers by synthetic

A. Dyer; F. H. Kadhim

1989-01-01

289

Synthesis, Characterization, and Activation of Zirconium and Hafnium Dialkyl Complexes that Contain a  

E-print Network

Synthesis, Characterization, and Activation of Zirconium and Hafnium Dialkyl Complexes that Contain of zirconium and hafnium complexes, [MepyN]MX2 (M ) Zr, X ) NMe2, Cl, OSO2CF3, CH2CHMe2, CH2Ph; M ) Hf, X ) NMe

Müller, Peter

290

Process for separating ceramics of uranium and plutonium from zirconium by hydriding and mixtures thereof  

Microsoft Academic Search

A process is provided involving the use of hydrogen for the separation of uranium and plutonium and mixtures thereof, from composite substances and assemblies or mixtures containing metallic and ceramic components where the metallic component is zirconium or a zirconium alloy and the ceramic component contains uranium and\\/or plutonium.

B. Cech; E. Kaderabek; T. Hanslik

1977-01-01

291

RADIOACTIVE INDICATOR DETERMINATION OF ZIRCONIUM AND PLUTONIUM DOUBLE SULFATES IN SATURATED POTASSIUM SULFATE SOLUTIONS  

Microsoft Academic Search

Zirconium and plutonium double sulfates were prepared by mixing in ; saturated potassium sulfate solution. The data indicate the absence of plutonium ; salt hydrolysis. The compositions of the double sulfates of plutonium(IV) and ; zirconium with potassium bisulf ate prepared under identical conditions are \\/sub ; 3\\/nt, KâPu(SOâ)â and KâZr(SOâ) ). (R. V.J.);

Bobrova

1960-01-01

292

Andrew Benson honored on birthday ? 97.  

PubMed

We present a brief account of the 97th birthday celebration of Andrew A. Benson, a scientific legend who is known, among other contributions, for his pioneering work on the path of carbon in photosynthesis (the Calvin-Benson cycle). PMID:25373526

Buchanan, Bob B; Douce, Roland

2015-02-01

293

Herman Schmit October `97 Reconfigurable Computing  

E-print Network

October `97 Performance Algorithm FPGA system Comparison CPU Speedup DNA Matching SPLASH 2 SPARC 10 4300 75MHz 33.8 FIR filter 1 Xilinx FPGA DSP 50MHz 17.9 Hidden Markov Model 1 Xilinx FPGA SPARC 10 24(s) Reconfigurable Coprocessor(s) Data-flow dominatedControl-flow dominated Memory Superscalar w/ Reconfigurable

Budiu, Mihai

294

97 6 23 562 305 3500  

E-print Network

.39% #12;-20- #12;-21- 2 Foresight Taiwan: An Executive Summary 97.6.18 Commissioned by the National Science Council, Foresight Taiwan is a project being conducted at Academia Sinica of science and technology in the economic future of Taiwan. Few would question the role science

295

19 CFR 4.97 - Salvage vessels.  

Code of Federal Regulations, 2011 CFR

...97 Customs Duties U.S. CUSTOMS AND BORDER...of the Saint Lawrence River through which the...authorized use.” (46 U.S.C. 316(d)) ...of the Saint Mary's River and Canal: * * *.” (46 U.S.C. 725) The...

2011-04-01

296

19 CFR 4.97 - Salvage vessels.  

Code of Federal Regulations, 2012 CFR

...97 Customs Duties U.S. CUSTOMS AND BORDER...of the Saint Lawrence River through which the...authorized use.” (46 U.S.C. 316(d)) ...of the Saint Mary's River and Canal: * * *.” (46 U.S.C. 725) The...

2012-04-01

297

19 CFR 4.97 - Salvage vessels.  

Code of Federal Regulations, 2013 CFR

...97 Customs Duties U.S. CUSTOMS AND BORDER...of the Saint Lawrence River through which the...authorized use.” (46 U.S.C. 316(d)) ...of the Saint Mary's River and Canal: * * *.” (46 U.S.C. 725) The...

2013-04-01

298

19 CFR 4.97 - Salvage vessels.  

...97 Customs Duties U.S. CUSTOMS AND BORDER...of the Saint Lawrence River through which the...authorized use.” (46 U.S.C. 316(d)) ...of the Saint Mary's River and Canal: * * *.” (46 U.S.C. 725) The...

2014-04-01

299

19 CFR 4.97 - Salvage vessels.  

Code of Federal Regulations, 2010 CFR

...97 Customs Duties U.S. CUSTOMS AND BORDER...of the Saint Lawrence River through which the...authorized use.” (46 U.S.C. 316(d)) ...of the Saint Mary's River and Canal: * * *.” (46 U.S.C. 725) The...

2010-04-01

300

Predicting the equilibria of point defects in zirconium oxide : a route to understand the corrosion and hydrogen pickup of zirconium alloys  

E-print Network

The performance of zirconium alloys in nuclear reactors is compromised by corrosion and hydrogen pickup. The thermodynamics and kinetics of these two processes are governed by the behavior of point defects in the ZrO? layer ...

Youssef, Mostafa Youssef Mahmoud

2014-01-01

301

The synthesis and characterization of Zirconium p-Phenylbis(phosphonate) Phosphate and other Zirconium Arylbis(phosphonates) for the application of ion exchange  

E-print Network

. These materials showed promise for many uses, of greatest interest were of catalysis and ion exchange. Zirconium p-Phenylbis(phosphonate) Phosphate was synthesized by several routes to investigate the inherent structural characteristics as they applied...

Bellinghausen, Paul Christian

2012-06-07

302

Control and monitoring of the localized corrosion of zirconium in acidic chloride solutions  

SciTech Connect

Zirconium in acidic chloride solutions which are contaminated with ferric or cupric cations is prone to localized corrosion. This tendency can be reduced by ensuring that the zirconium surface is clean and smooth. In this paper, the effect of surface condition on the localized corrosion of zirconium in acidic chloride solutions is predicted with potentiodynamic scans. These predictions are confirmed by weight loss tests on various combinations of surface finish and acid concentrations. A real time indication of localized corrosion is seen by monitoring the electrochemical noise produced between two similar electrodes immersed in an acidic chloride solutions. Electrochemical noise monitoring correlates well with the predictions from potentiodynamic and weight loss experiments. The electrochemical noise results show that while an elevated (more anodic) potential caused by ferric ion contamination may be a necessary condition for localized corrosion, it is not a sufficient condition: A smooth, clean zirconium surface reduces the localized corrosion of zirconium.

Fahey, J.; Holmes, D.; Yau, T.L. [Teledyne Wah Chang, Albany, OR (United States)

1995-09-01

303

Fundamental studies into zirconium modified phosphonic acid based ionic membranes  

NASA Astrophysics Data System (ADS)

The demand for a sustainable energy economy requires the development of new solid stare electrochemical energy conversion devices. Ionic membranes are the bases for most of these devices. Solid super acids based on zirconium phosphonates show great promise for development into these membranes. Copolymers of vinyl phosphonic acid with zirconium vinyl phosphonate have been synthesized via UV free radical polymerization from immiscible mixtures into amorphous, transparent, water stable, flexible membranes. Ion exchange capacities range from 6 to 10 meq/g corresponding to equivalent weights well below 200 g/mol. A 20wt% loading of the VZP co-monomer is XRD amorphous. It is shown that 1.5 of the 2 protons in the beginning acidic groups are dissociated in the 20wt% VZP loaded ionomer allowing these materials to have high proton conductivities, up to and exceeding 0.1 S cm^-1 at 80°C and 80%RH. Water uptake measurementsshow very little swelling of the material below 70%RH and ca. 1 water per proton at low RH. Proton conductivity under dry conditions, roughly 0.05 S cm-1 with a lambda < 1, indicates that the material conducts protons under limiting hydration conditions and strongly implicates transport by a pure Grotthuss mechanism. Through this work, it has been demonstrated that zirconium vinyl phosphonate can, in fact, be dispersed and incorporated into a polymer to create new, hybrid organic-inorganic ionomers. High conductivities over 0.15 S/cm have been shown for multiple formulations of these ionomers, which is approaching conductivities that are comparable to liquid and molten phosphoric and phosphonic acids. Phosphonic acid functionalization yielded high proton conductivities, however the increased ionic character rendered the ionomer vulnerable to attack from water. Annealing provides a rise in conductivity at 150 degrees Celsius, but shows decreases after heating to 175 degrees Celsius, where the ionomer is obviously starting to degrade.

Schlichting, Gregory Joseph

304

The abundances of zirconium and hafnium in the solar system  

NASA Technical Reports Server (NTRS)

The concentrations of zirconium and hafnium have been determined in the Orgueil, Murchison, Allende, Bruderheim, and Alais meteorites by radiochemical neutron activation analysis. The mean Zr/Hf weight ratio in the first four of these meteorites is 31.3 (plus or minus 2.2), indicating no major fractionation of Zr from Hf. Alais contains anomalously high amounts of many refractory lithophile elements, including Zr and Hf. Orgueil contains 3.1 ppm Zr and 0.11 ppm Hf, corresponding to 9.0 and 0.16 atoms, respectively, relative to 1 million Si atoms.

Ganapathy, R.; Papia, G. M.; Grossman, L.

1976-01-01

305

Analysis of irradiation growth in zirconium-base alloy  

NASA Astrophysics Data System (ADS)

Irradiation induced growth phenomena in zirconium-base alloy have been investigated on the basis of the numerical results obtained by dynamical-method computer simulations. Point defect trapping by solute atoms causes transient growth strain which is recoverable during temperature cycling. The growth strain change of cold-worked Zircaloy-2 irradiated at 553 K can be explained by a dislocation climb and a net inflow of vacancies into grain boundaries. The effects of various parameters such as grain size are also discussed.

Fuse, Motomasa

1986-09-01

306

Structure and thermal stability of mesostructured zirconium oxophosphates  

Microsoft Academic Search

Highly ordered mesoporous zirconium oxophosphates (designated as ZOP) with hexagonal P63\\/mmc and cubic Fm3¯m symmetries were firstly prepared by using gemini cationic surfactants as templates. It has been found that the thermal stability was elevated with the structure curvature order: cubic Ia3¯d2D-hexagonalp6mmcubicFm3¯m, hexagonal P63\\/mmc and cubic Pm3¯n. The ZOP mesoporous materials with cubic Fm3¯m and hexagonal P63\\/mmc structures were stable

Yifeng Zhang; Yongsheng Li; Yasuhiro Sakamoto; Osamu Terasaki; Shunai Che

2007-01-01

307

Zirconium(IV) dilanthanum(III) penta­sulfide  

PubMed Central

Zirconium(IV) dilanthanum(III) penta­sulfide, ZrLa2S5, crystallizes with four formula units in the space group Pnma in the U3S5 structure type. The asymmetric unit comprises one Zr, one La and four S atoms. The Zr and three S atoms are situated on mirror planes. The structure consists of LaS8 face-sharing bicapped distorted trigonal prisms and ZrS7 edge-sharing monocapped octa­hedra. PMID:22199468

Raw, Adam D.; Ibers, James A.

2011-01-01

308

Asia-Pacific Economic Cooperation (APEC) 97  

NSDL National Science Digital Library

APEC 97 is the official site for the Asia-Pacific Economic Cooperation (APEC) Leaders and Ministers meeting held in Vancouver, Canada from November 21 to November 25, 1997. It provides a short history of APEC, short biographical notes on the leaders and ministers attending the meeting, in-depth information about the APEC economies, listings of venues and events, and a news section with up-to-date news of APEC 97. APEC is a grouping of 18 Asia-Pacific economies formed in 1989 to promote trade and cooperation in the region. Traditionally, the APEC meeting has focused on trade issues, but this year's focus was the economic crisis in Southeast Asia and South Korea.

309

Synthetic environment technologies in STOW 97  

NASA Astrophysics Data System (ADS)

The synthetic theater of war (STOW) is the major application of a Defense Advanced Research Projects Agency (DARPA) thrust in advanced distributed simulation (ADS). The STOW Program focuses on an advanced concept technology demonstration (ACTD) termed STOW 97 sponsored by DARPA with the United States Atlantic Command (USACOM). The successful implementation of STOW 97 technologies in November 1997 with the United Endeavor 98-1 exercise will mark the full operational capacity of the USACOM Joint Training, Analysis and Simulation Center. To support ADS applications up to the Joint Task Force level, STOW seeks to develop and demonstrate technologies enabling the integration of war-fighting through virtual and constructive simulations from geographically distributed locations in a common synthetic battlespace.

Turner, Jeffrey T.; Koklauner, Karl

1997-10-01

310

STS-97 ISS Science Payloads Briefing  

NASA Technical Reports Server (NTRS)

John Un, International Space Station (ISS) Lead Increment Scientist, gives an overview of the STS-97 Endeavour mission payload (PV Module P6) and Expedition 1 crew. He describes the research and experimentation to take place on the ISS in the following fields: (1) Life Sciences, (2) Microgravity Research, (3) Commercial, (4) Space Sciences, and (5) Earth Sciences. Observations of Earth include images of the Aral Sea in central Asia and fires in Mongolia. Mr. Un then answers questions from the press.

2000-01-01

311

Vancouver Sun APEC 97 news archive  

NSDL National Science Digital Library

The Vancouver Sun provides a comprehensive news archive of the issues and events at APEC 97, the APEC Leaders and Ministers meeting held in Vancouver, Canada from November 21 to November 25, 1997. APEC is a grouping of 18 Asia-Pacific economies formed in 1989 to promote trade and cooperation in the region. Traditionally, the APEC meeting has focused on trade issues, but this year's focus was the economic crisis in Southeast Asia and South Korea.

312

Nucleation and growth kinetics of zirconium-oxo-alkoxy nanoparticles.  

PubMed

Nucleation and growth of zirconium-oxo-alkoxy (ZOA) nanoparticles were studied in a sol-gel process in n-propanol solution at a hydrolysis ratio H between 1.0 and 2.7 and zirconium-n-propoxyde precursor concentrations between 0.10 and 0.15 mol l(-1). The chemical transformations were conducted in quasi-perfect micromixing conditions (Damköhler number Da ? 1) and the nanoparticle size evolution was monitored in situ with the light scattering method. The size of primary nanoparticles (nuclei) 2R0 = 3.6 nm was found to be almost independent of the preparation conditions. A remarkable similarity with the titanium-oxo-alkoxy (TOA) nanoparticles was observed. In particular, both systems show the induction stage of the sol-gel growth for a hydrolysis ratio H > 2.0 and stable oxometallate units for H? 2.0. However in contrast to TOA, no stable hierarchical ZOA units (clusters) with R0?R? 1.0 nm were observed, which makes this system less stable against aggregation, leading to polydispersed nanoparticles. PMID:25502510

Labidi, Sana; Jia, Zixian; Amar, Mounir Ben; Chhor, Khay; Kanaev, Andrei

2015-01-28

313

Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics  

NASA Astrophysics Data System (ADS)

The optimization of zirconium-based alloys used for nuclear fuel cladding aims to reduce hydrogen pickup during operation, and the associated cladding degradation. The present study focuses on precisely and accurately measuring hydrogen pickup fraction for a set of alloys to specifically investigate the effects of alloying elements, microstructure and corrosion kinetics on hydrogen uptake. To measure hydrogen concentrations in zirconium alloys two techniques have been used: a destructive technique, Vacuum Hot Extraction, and a non-destructive one, Cold Neutron Prompt Gamma Activation Analysis. The results of both techniques show that hydrogen pickup fraction varies significantly with exposure time and between alloys. A possible interpretation of the results is that hydrogen pickup results from the need to balance charge. That is, the pickup of hydrogen shows an inverse relationship to oxidation kinetics, indicating that, if transport of charged species is rate limiting, oxide transport properties such as oxide electronic conductivity play a key role in the hydrogen pickup mechanism. Alloying elements (either in solid solution or in precipitates) would therefore impact the hydrogen pickup fraction by affecting charge transport.

Couet, Adrien; Motta, Arthur T.; Comstock, Robert J.

2014-08-01

314

Zirconium speciation in lactate solutions and polyacrylate gels.  

PubMed

Controlling gelation kinetics is an important objective for several applications (ceramic and thin film syntheses, reduction in permeability of porous rock, etc). There is a growing interest in studying the gelation of polymers by zirconium, a crosslinker of lower toxicity than the chromium which is still commonly used. XAS at the Zr K-edge was performed at the European Synchrotron Radiation Facility (ESRF) on the BM32 beamline. The fluorescence detection was used to carry out successful in situ speciation at concentrations as low as 36 ppm. The Zr speciation was determined both in ZrLa (where La stands for lactate) aqueous solutions and in gels of a terpolymer of acrylamide having 2% of zirconium reactive acrylate side groups and 2% of sulfonate groups introduced to prevent syneresis. XANES results show that Zr is always in a dodecahedral geometry. In ZrLa solutions. EXAFS results indicate that Zr species grow from a dimer Zr2(La)6 to a tetramer (Zr4(La)x) and then to larger polymers resulting from tetramer associations, as the Zr concentration decreases from 51840 ppm to 36ppm. In polymer gels, Zr species appear to be dimers at pH 6 while tetramers are found when gelation occurred at pH 7. Calculations taking into account multiple scattering effects as well as dynamic molecular calculation confirmed conclusions derived from conventional EXAFS analysis. PMID:11512896

Rose, J; Chauveteau, G; Tabary, R; Renard, M; Omari, A; Toulhoat, H

2001-03-01

315

Layered zirconium phosphonate with inorganic-organic hybrid structure: Preparation and its assembly with DNA  

NASA Astrophysics Data System (ADS)

An aminoethoxy-functionalized zirconium phosphonate (Zr(O3POCH2CH2NH2)2·3H2O), abbreviated as ZrRP (R=OCH2CH2NH2), with layered structure has been synthesized. This layered compound possesses the characteristic of inorganic-organic hybrid, due to the covalently linked aminoethoxy in the host layer. The anion exchanged property of this zirconium phosphonate is suitable for the direct intercalation of negatively charged DNA, which is different from these reported zirconium phosphates or zirconium phosphonates. As a precursor, this prepared zirconium phosphonate was utilized to fabricate a novel DNA/ZrRP binary hybrid via a delamination-reassembly procedure. The release behavior of DNA from the DNA/ZrRP composite was investigated at different medium pH, because the combination between zirconium phosphonate sheets and DNA was pH-dependent sensitively. Moreover, the helical conformation of DNA was almost retained after the intercalation and release process. These properties of the DNA/ZrRP composite suggested the potential application of layered zirconium phosphonate as a non-viral vector in gene delivery.

Liu, Li-Min; Lu, Guo-Yuan; Jiang, Li-Ping; Zhu, Jun-Jie

2014-07-01

316

Direct observation of zirconium segregation to dislocations and grain boundaries in NiAl  

SciTech Connect

Segregation of zirconium to dislocations in microalloyed NiAl has been directly observed in the atom probe field ion microscopy (APFIM). Approximately two thirds of the <100> dislocations in the NiAl matrix exhibited zirconium segregation. Zirconium-rich regions with ribbon-like morphology were also detected in the NiAl matrix. It is suggested that these regions are associated with dislocations. These results support the suggestion that the substantial increase in ductile-to-brittle transition temperature (DBTT) of the zirconium-doped alloy is due to pinning of dislocations by zirconium. Since the mechanism underlying the DBTT in binary NiAl is not understood, it would be of interest to examine the possibility of a similar pinning of dislocations by trace interstitial and other impurities in the undoped alloy. Segregation of zirconium to grain boundaries has also been observed in the APFIM. This result indicates the possible strengthening of grain boundaries has also been observed in the APFIM. This result indicates the possible strengthening of grain boundaries due to zirconium segregation and is consistent with the change in the fracture mode from intergranular in the undoped NiAl to a mixture of intergranular and transgranular mode in zirconium-doped NiAl. The NiAl matrix was heavily depleted of both solutes molybdenum and zirconium. Small Mo-rich precipitates observed in the matrix and at grain boundaries and the ribbon-like Zr-rich regions are likely to contributed to the increase in yield stress through precipitation hardening.

Jayaram, R. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering] [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering; Miller, M.K. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Division] [Oak Ridge National Lab., TN (United States). Metals and Ceramics Division

1995-07-01

317

46 CFR 56.97-40 - Installation tests.  

Code of Federal Regulations, 2010 CFR

...AND APPURTENANCES Pressure Tests § 56.97-40 Installation tests. (a) The following piping systems shall be hydrostatically leak tested in the presence of a...the section on initial service leak test, § 56.97-38....

2010-10-01

318

47 CFR 97.513 - VE session manager requirements.  

Code of Federal Regulations, 2011 CFR

...Section 97.513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.513 VE session manager requirements. (a) A VE...

2011-10-01

319

47 CFR 97.401 - Operation during a disaster.  

Code of Federal Regulations, 2012 CFR

...Section 97.401 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.401 Operation during a disaster. A station in,...

2012-10-01

320

47 CFR 97.105 - Control operator duties.  

Code of Federal Regulations, 2013 CFR

...Section 97.105 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.105 Control operator duties. (a) The control operator must...

2013-10-01

321

47 CFR 97.401 - Operation during a disaster.  

Code of Federal Regulations, 2013 CFR

...Section 97.401 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.401 Operation during a disaster. A station in,...

2013-10-01

322

47 CFR 97.519 - Coordinating examination sessions.  

Code of Federal Regulations, 2010 CFR

...Section 97.519 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.519 Coordinating examination sessions. (a) A VEC must...

2010-10-01

323

47 CFR 97.407 - Radio amateur civil emergency service.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Radio amateur civil emergency service. 97.407...SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.407 Radio amateur civil emergency service....

2012-10-01

324

47 CFR 97.401 - Operation during a disaster.  

Code of Federal Regulations, 2011 CFR

...Section 97.401 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.401 Operation during a disaster. A station in,...

2011-10-01

325

47 CFR 97.519 - Coordinating examination sessions.  

Code of Federal Regulations, 2011 CFR

...Section 97.519 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.519 Coordinating examination sessions. (a) A VEC must...

2011-10-01

326

47 CFR 97.519 - Coordinating examination sessions.  

Code of Federal Regulations, 2013 CFR

...Section 97.519 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.519 Coordinating examination sessions. (a) A VEC must...

2013-10-01

327

47 CFR 97.407 - Radio amateur civil emergency service.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Radio amateur civil emergency service. 97.407...SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.407 Radio amateur civil emergency service....

2013-10-01

328

47 CFR 97.105 - Control operator duties.  

Code of Federal Regulations, 2010 CFR

...Section 97.105 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.105 Control operator duties. (a) The control operator must...

2010-10-01

329

47 CFR 97.513 - VE session manager requirements.  

Code of Federal Regulations, 2012 CFR

...Section 97.513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.513 VE session manager requirements. (a) A VE...

2012-10-01

330

47 CFR 97.513 - VE session manager requirements.  

Code of Federal Regulations, 2013 CFR

...Section 97.513 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.513 VE session manager requirements. (a) A VE...

2013-10-01

331

47 CFR 97.407 - Radio amateur civil emergency service.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Radio amateur civil emergency service. 97.407...SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97.407 Radio amateur civil emergency service....

2011-10-01

332

47 CFR 97.105 - Control operator duties.  

Code of Federal Regulations, 2011 CFR

...Section 97.105 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.105 Control operator duties. (a) The control operator must...

2011-10-01

333

47 CFR 97.105 - Control operator duties.  

Code of Federal Regulations, 2012 CFR

...Section 97.105 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.105 Control operator duties. (a) The control operator must...

2012-10-01

334

47 CFR 97.103 - Station licensee responsibilities.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Station licensee responsibilities. 97.103 Section...SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.103 Station licensee responsibilities. (a) The...

2010-10-01

335

46 CFR 97.01-2 - Incorporation by reference.  

Code of Federal Regulations, 2010 CFR

...12-616260-01 (1996)—97.36-1 International Maritime Organization (IMO) Publications Section, 4 Albert Embankment, London, SE1 7SR United Kingdom Resolution A.654(16), Graphical Symbols for Fire Control Plans—97.36-1...

2010-10-01

336

30 CFR 18.97 - Inspection of machines; minimum requirements.  

...2014-07-01 false Inspection of machines; minimum requirements. 18.97...Equipment § 18.97 Inspection of machines; minimum requirements. (a) Except as provided in § 18.95, all machines approved under the...

2014-07-01

337

30 CFR 18.97 - Inspection of machines; minimum requirements.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Inspection of machines; minimum requirements. 18.97...Equipment § 18.97 Inspection of machines; minimum requirements. (a) Except as provided in § 18.95, all machines approved under the...

2011-07-01

338

30 CFR 18.97 - Inspection of machines; minimum requirements.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Inspection of machines; minimum requirements. 18.97...Equipment § 18.97 Inspection of machines; minimum requirements. (a) Except as provided in § 18.95, all machines approved under the...

2010-07-01

339

30 CFR 18.97 - Inspection of machines; minimum requirements.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Inspection of machines; minimum requirements. 18.97...Equipment § 18.97 Inspection of machines; minimum requirements. (a) Except as provided in § 18.95, all machines approved under the...

2012-07-01

340

30 CFR 18.97 - Inspection of machines; minimum requirements.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Inspection of machines; minimum requirements. 18.97...Equipment § 18.97 Inspection of machines; minimum requirements. (a) Except as provided in § 18.95, all machines approved under the...

2013-07-01

341

24 CFR 200.97 - Adjustments resulting from cost certification.  

...2014-04-01 false Adjustments resulting from cost certification. 200.97 Section 200...Eligibility Requirements for Existing Projects Cost Certification § 200.97 Adjustments resulting from cost certification. (a) Fee simple...

2014-04-01

342

24 CFR 200.97 - Adjustments resulting from cost certification.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Adjustments resulting from cost certification. 200.97 Section 200...Eligibility Requirements for Existing Projects Cost Certification § 200.97 Adjustments resulting from cost certification. (a) Fee simple...

2013-04-01

343

24 CFR 200.97 - Adjustments resulting from cost certification.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Adjustments resulting from cost certification. 200.97 Section 200...Eligibility Requirements for Existing Projects Cost Certification § 200.97 Adjustments resulting from cost certification. (a) Fee simple...

2012-04-01

344

24 CFR 200.97 - Adjustments resulting from cost certification.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Adjustments resulting from cost certification. 200.97 Section 200...Eligibility Requirements for Existing Projects Cost Certification § 200.97 Adjustments resulting from cost certification. (a) Fee simple...

2011-04-01

345

24 CFR 200.97 - Adjustments resulting from cost certification.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Adjustments resulting from cost certification. 200.97 Section 200...Eligibility Requirements for Existing Projects Cost Certification § 200.97 Adjustments resulting from cost certification. (a) Fee simple...

2010-04-01

346

46 CFR 111.97-9 - Overcurrent protection.  

Code of Federal Regulations, 2013 CFR

...111.97-9 Section 111.97-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Electric Power-Operated Watertight Door Systems §...

2013-10-01

347

7 CFR 3201.97 - Sun care products.  

...2014-01-01 2014-01-01 false Sun care products. 3201.97 Section 3201...PROCUREMENT Designated Items § 3201.97 Sun care products. (a) Definition. Products including sunscreens, sun blocks, and suntan lotions that are...

2014-01-01

348

7 CFR 3201.97 - Sun care products.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Sun care products. 3201.97 Section 3201...PROCUREMENT Designated Items § 3201.97 Sun care products. (a) Definition. Products including sunscreens, sun blocks, and suntan lotions that are...

2013-01-01

349

46 CFR 97.37-23 - Hand portable fire extinguishers.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Hand portable fire extinguishers. 97.37-23...Emergency Equipment, Etc. § 97.37-23 Hand portable fire extinguishers. (a) Each hand portable fire extinguisher shall be...

2010-10-01

350

46 CFR 97.37-23 - Hand portable fire extinguishers.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Hand portable fire extinguishers. 97.37-23...Emergency Equipment, Etc. § 97.37-23 Hand portable fire extinguishers. (a) Each hand portable fire extinguisher shall be...

2011-10-01

351

46 CFR 97.37-23 - Hand portable fire extinguishers.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Hand portable fire extinguishers. 97.37-23...Emergency Equipment, Etc. § 97.37-23 Hand portable fire extinguishers. (a) Each hand portable fire extinguisher shall be...

2013-10-01

352

46 CFR 97.37-23 - Hand portable fire extinguishers.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Hand portable fire extinguishers. 97.37-23...Emergency Equipment, Etc. § 97.37-23 Hand portable fire extinguishers. (a) Each hand portable fire extinguisher shall be...

2012-10-01

353

46 CFR 97.37-23 - Hand portable fire extinguishers.  

... 2014-10-01 2014-10-01 false Hand portable fire extinguishers. 97.37-23...Emergency Equipment, Etc. § 97.37-23 Hand portable fire extinguishers. (a) Each hand portable fire extinguisher shall be...

2014-10-01

354

46 CFR 97.30-5 - Accidents to machinery.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Accidents to machinery. 97.30-5 Section...MISCELLANEOUS VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event...

2012-10-01

355

46 CFR 97.30-5 - Accidents to machinery.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Accidents to machinery. 97.30-5 Section...MISCELLANEOUS VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event...

2013-10-01

356

46 CFR 97.30-5 - Accidents to machinery.  

...2014-10-01 2014-10-01 false Accidents to machinery. 97.30-5 Section...MISCELLANEOUS VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event...

2014-10-01

357

46 CFR 97.30-5 - Accidents to machinery.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Accidents to machinery. 97.30-5 Section...MISCELLANEOUS VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event...

2010-10-01

358

46 CFR 97.30-5 - Accidents to machinery.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Accidents to machinery. 97.30-5 Section...MISCELLANEOUS VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-5 Accidents to machinery. (a) In the event...

2011-10-01

359

34 CFR 97.116 - General requirements for informed consent.  

Code of Federal Regulations, 2010 CFR

...false General requirements for informed consent. 97.116 Section 97...116 General requirements for informed consent. Except as provided...obtained the legally effective informed consent of the subject or the...

2010-07-01

360

34 CFR 97.116 - General requirements for informed consent.  

...false General requirements for informed consent. 97.116 Section 97...116 General requirements for informed consent. Except as provided...obtained the legally effective informed consent of the subject or the...

2014-07-01

361

34 CFR 97.116 - General requirements for informed consent.  

Code of Federal Regulations, 2013 CFR

...false General requirements for informed consent. 97.116 Section 97...116 General requirements for informed consent. Except as provided...obtained the legally effective informed consent of the subject or the...

2013-07-01

362

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...RULES IFR ALTITUDES Special Federal Aviation Regulation No. 97 Editorial...

2011-01-01

363

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...BOARD SUCH AIRCRAFT Special Federal Aviation Regulation No. 97 Editorial...

2010-01-01

364

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...SUPPLEMENTAL OPERATIONS Special Federal Aviation Regulation No. 97 Editorial...

2010-01-01

365

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...SUPPLEMENTAL OPERATIONS Special Federal Aviation Regulation No. 97 Editorial...

2011-01-01

366

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...BOARD SUCH AIRCRAFT Special Federal Aviation Regulation No. 97 Editorial...

2011-01-01

367

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...AND REPORTING POINTS Special Federal Aviation Regulation No. 97 Editorial...

2011-01-01

368

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...AND REPORTING POINTS Special Federal Aviation Regulation No. 97 Editorial...

2010-01-01

369

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...IN COMMON CARRIAGE Special Federal Aviation Regulation No. 97 Editorial...

2010-01-01

370

14 CFR Appendix - Special Federal Aviation Regulation No. 97  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special Federal Aviation Regulation No. 97 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...IN COMMON CARRIAGE Special Federal Aviation Regulation No. 97 Editorial...

2011-01-01

371

29 CFR 97.20 - Standards for financial management systems.  

...2013-07-01 true Standards for financial management systems. 97.20 Section...97.20 Standards for financial management systems. (a) A...applicable statutes. (b) The financial management systems of other...

2014-07-01

372

29 CFR 97.20 - Standards for financial management systems.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Standards for financial management systems. 97.20 Section...97.20 Standards for financial management systems. (a) A...applicable statutes. (b) The financial management systems of other...

2012-07-01

373

29 CFR 97.20 - Standards for financial management systems.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Standards for financial management systems. 97.20 Section...97.20 Standards for financial management systems. (a) A...applicable statutes. (b) The financial management systems of other...

2013-07-01

374

46 CFR 97.37-11 - Carbon dioxide warning signs.  

...2014-10-01 2014-10-01 false Carbon dioxide warning signs. 97.37-11...Emergency Equipment, Etc. § 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

2014-10-01

375

Histopathological and microanalytical study of zirconium dioxide and barium sulphate in bone cement.  

PubMed Central

AIMS: To report the appearances of zirconium dioxide and barium sulphate in interface membranes, synovium, and other tissues around joint prostheses. METHODS: Histological sections from 23 specimens were reviewed by light microscopy and polarisation. Scanning electron microscopy and x ray microanalysis were performed on routinely processed paraffin wax sections. RESULTS: Polyethylene, metals, and polymethylmethacrylate cement debris were easily recognisable. Almost all the cement remnants contained either zirconium dioxide or barium sulphate, confirmed by microanalysis. The contrast media had characteristic light microscopic appearances. Zirconium was identified in macrophages away from cement remnants. CONCLUSION: The presence of radiographic contrast media in tissues around prosthetic joints is common but not widely recognised. Images PMID:1452794

Keen, C. E.; Philip, G.; Brady, K.; Spencer, J. D.; Levison, D. A.

1992-01-01

376

A NOVEL LAYERED ZIRCONIUM PHOSPHATE Zr2O3(HPO4). SYNTHESIS AND CHARACTERIZATION OF PROPERTIES  

Microsoft Academic Search

Several novel crystalline layered zirconium phosphates with composition Zr2O3(HPO4)-nH2O (M=Na, K) were prepared by the partial hydrolytic decomposition of amorphous or crystalline a-zirconium phosphates in alkaline media under mild hydrothermal conditions. The corresponding Li-and Cs-forms of this phosphate were obtained by successive treatment of Na- or K-forms with LiOH or CsOH solutions. Two hydrogen forms of the novel zirconium phosphate

Anatoly I. Bortun; Lyudmila N. Bortun; Abraham Clearfield

1997-01-01

377

Physicomechanical properties of the surface of a zirconium alloy modified by a pulsed ion beam  

NASA Astrophysics Data System (ADS)

The physicomechanical properties of the surface of the Zr-1% Nb zirconium alloy modified by a pulsed carbon ion beam with a pulse duration of 80 ns, an energy of 200 keV, and a current density of 120 A/cm2 are studied at four regimes having different numbers of pulses. Irradiation by a carbon ion beam results in hardening of the surface layer to a depth of 2 ?m, grain refinement to 0.15-0.8 ?m, zirconium carbide formation, and a decrease in the hydrogen permeability of the zirconium alloy.

Chernov, I. P.; Berezneeva, E. V.; Beloglazova, P. A.; Ivanova, S. V.; Kireeva, I. V.; Lider, A. M.; Remnev, G. E.; Pushilina, N. S.; Cherdantsev, Yu. P.

2014-04-01

378

The effect of purity on high-temperature oxidation of zirconium  

SciTech Connect

The oxidation kinetics of zirconium of different purities were studied over the temperature range of 600-1300[degrees]C ([alpha]- and [beta]-phases). The structure of the oxidized specimens was examined. TGA, XRD, EPMA, SEM, metallographic analysis, and microhardness measurements were carried out. Impurity elements were found to increase the oxidation rate of technical zirconium. The mechanism of the effect of impurity elements on zirconium oxidation was shown to differ for the [alpha]- and [beta]-phases. Activation energies were calculated for the parabolic and linear stages of oxidation.

Voitovich, V.B.; Lavrenko, V.A.; Voitovich, R.F.; Golovko, E.I. (Institute for Problems of Material Science, Kiev (Ukraine))

1994-10-01

379

46 CFR 97.15-55 - Requirements for fuel oil.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Requirements for fuel oil. 97.15-55 Section 97.15-55... § 97.15-55 Requirements for fuel oil. (a) It shall be the duty of...the log to be made of each supply of fuel oil received on board, stating the...

2010-10-01

380

46 CFR 97.16-1 - Use of auto pilot.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Use of auto pilot. 97.16-1 Section 97.16-1 Shipping... CARGO AND MISCELLANEOUS VESSELS OPERATIONS Auto Pilot § 97.16-1 Use of auto pilot. Except as provided in 33 CFR...

2010-10-01

381

27 CFR 24.97 - Use on premises.  

Code of Federal Regulations, 2013 CFR

...premises. 24.97 Section 24.97 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Administrative and Miscellaneous...24.97 Use on premises. (a) Analysis or testing. The proprietor...

2013-04-01

382

27 CFR 24.97 - Use on premises.  

...premises. 24.97 Section 24.97 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL WINE Administrative and Miscellaneous...24.97 Use on premises. (a) Analysis or testing. The proprietor...

2014-04-01

383

46 CFR 97.16-1 - Use of auto pilot.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Use of auto pilot. 97.16-1 Section 97.16-1 Shipping... CARGO AND MISCELLANEOUS VESSELS OPERATIONS Auto Pilot § 97.16-1 Use of auto pilot. Except as provided in 33 CFR...

2011-10-01

384

Separation of Zirconium from Uranium in U-Zr Alloys Using a Chlorination Process  

E-print Network

The fundamental behavior underpinning a new processing concept was demonstrated which is capable of separating uranium from zirconium in U-Zr alloys through the formation and selective volatilization of their respective chlorides. Bench...

Parkison, Adam J

2013-06-04

385

JOURNAL OF MATERIALS SCIENCE 36 (2001) 77 86 Synthesis of yttria-doped strontium-zirconium  

E-print Network

JOURNAL OF MATERIALS SCIENCE 36 (2001) 77­ 86 Synthesis of yttria-doped strontium-zirconium oxide densification, than co-precipitated powders. C 2001 Kluwer Academic Publishers 1. Introduction Strontium

Iglesia, Enrique

386

Electrochemical formation of uranium-zirconium alloy in LiCl-KCl melts  

NASA Astrophysics Data System (ADS)

Since zirconium is considered an electrochemically active species under practical conditions of the electrorefining process, it is crucial to understand the electrochemical behavior of zirconium in LiCl-KCl melts containing actinide ions. In this study, the electrochemical codeposition of uranium and zirconium on a solid cathode was performed. It was found that the ?-(U, Zr) phase, which is the only intermediate phase of the uranium-zirconium binary alloy system, was deposited on a tantalum substrate by potentiostatic electrolysis at -1.60 V (vs. Ag +/Ag) in LiCl-KCl melts containing 0.13 in mol% UCl 3 and 0.23 in mol% ZrCl 4 at 773 K. To our knowledge, this is the first report on the electrochemical formation of the ?-(U, Zr) phase. The relative partial molar properties of uranium in the ?-(U, Zr) phase were evaluated by measuring the open-circuit-potentials of the electrochemically prepared ?-phase electrode.

Murakami, Tsuyoshi; Kato, Tetsuya; Kurata, Masaki; Yamana, Hajimu

2009-11-01

387

Development of a plasma coating system for induction melting zirconium in a graphite crucible  

SciTech Connect

A plasma coating system has been developed for induction melting zirconium at 1900 C using a graphite crucible. This laminated coating system consists of plasma spraying the following materials onto the graphite: (1) molybdenum or tungsten, (2) a 50% blend by weight of the metal powder and calcia-stabilized zirconium oxide, and (3) calcia-stabilized zirconia followed by painting a final coating of nonstabilized zirconia on top of the plasma-sprayed coating system. Zirconium was melted in argon using both laminating systems without any degradation of the graphite crucible and with only a minimal amount of carbon absorption. This novel approach that is being proposed as an alternative method of melting zirconium alloys offers substantial cost savings over the standard practice of electric arc melting using a consumable electrode.

Bird, E.L.; Holcombe, C.E. Jr.

1993-05-26

388

Structure of zirconium-rich alloys of the Zr-Ru system  

NASA Astrophysics Data System (ADS)

The equilibrium and metastable phases of zirconium-rich binary alloys of the Zr-Ru system are studied experimentally. Maximum solubility of ruthenium is found to equal 11 at.% in beta-zirconium at the eutectic temperature of 1250 C, and about 1 at.% in alpha-zirconium at 600 C. Ruthenium is shown to reduce the zirconium reversible alpha-beta transformation temperature. Eutectoid decomposition of beta-solid solution was not observed at temperatures up to 600 C. In alloys quenched from 1000 to 800 C, the omega-phase was found with the following lattice periods: a = 4.997, c = 3.134 A, and c/a = 0.627.

Eremenko, V. N.; Semenova, E. L.; Shtepa, T. D.

1980-04-01

389

21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

2010-04-01

390

21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.  

Code of Federal Regulations, 2011 CFR

... 2010-04-01 true Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

2011-04-01

391

Engineering analysis of low enriched uranium fuel using improved zirconium hydride cross sections  

E-print Network

. All of these simulations used improved zirconium hydride cross sections that were provided by Dr. Ayman Hawari at North Carolina State University. The neutronic and thermal analysis showed that the reactor will operate with approximately the same fuel...

Candalino, Robert Wilcox

2006-10-30

392

Methods for Investigating Gas Bubble Formation in Uranium-Zirconium Alloys  

E-print Network

Uranium-zirconium alloy nuclear fuels have many advantages as compared with ceramic fuels, especially for fast reactor systems. However, metallic fuels aren’t currently used in commercial power production due in part to issues with fuel swelling...

Mews, Kathryn Ann Wright

2013-05-06

393

Cation-exchange separation of hafnium and zirconium from accompanying ions.  

PubMed

Hafnium and zirconium are not retained on the strongly acidic cation-exchange resin Dowex 50 from a mixture consisting of methanol and 12M nitric acid (19:1) which is 0.1M in trioctylphosphine oxide. On the other hand most other elements investigated are strongly adsorbed on the resin from this medium so that they are readily separated from hafnium and zirconium. These elements include titanium, rare earths, alkali metals, alkaline earth metals, iron, cobalt, manganese and zinc. This separation technique has been found to be suitable for the separation of tracer and milligram amounts of hafnium and zirconium from accompanying metal ions. If in place of methanol other organic solvents such as acetone, tetrahydrofuran and methyl glycol are used the selectivity of the separation of zirconium and hafnium from the other elements is decreased. The same effect is observed when hydrochloric acid is used in the mixtures instead of nitric acid. PMID:18960465

Korkisch, J; Orlandini, K A

1969-01-01

394

Wear resistant zirconium base alloy article for water reactors  

SciTech Connect

In a water reactor operating environment, the combination having improved fretting wear resistance is described comprising: an elongated tubular water displacer rod; having a low neutron absorption cross section guide support plates distributed along the length of the water displacer rod; the water displacer rod intersecting the guide support plates through apertures in the guide support plates; the water displacer rod having a plurality of spaced apart annular electrospark deposited coatings, each coating facing the wall of a respective aperture, the electrospark deposited coatings comprising Cr/sub 2/C/sub 3/; wherein the water displacer rod has a tube wall composed of a zirconium base alloy; and wherein the guide support plates are composed of a stainless steel alloy.

Gillett, J.E.; Shockling, L.A.; Sherwood, D.G.

1988-03-01

395

Fabrication of NiO/zirconium oxide nanofibers by electrospinning.  

PubMed

The electrospinning technique has been used to fabricate 1D inorganic-organic composite nanofibers from solutions containing poly(vinyl alcohol) (PVA) and suitable aqueous precursors of nickel and zirconium ions. Upon calcination, nickel oxide/zirconia nanofibers retained the original morphological features of as-spun nanofibers. X-ray diffraction was used to identify the crystalline nature of the final product and analytical tools such as Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed to elucidate the pathway of ceramic phase formation and the systematic evolution of morphological features in the as-spun and calcined fibers. These fibers will find potential applications in biomedical field. PMID:25491841

Sundarrajan, Subramanian; Venkatesan, Arunachalam; Agarwal, Satya R; Shaik Anwar Ahamed, Nabeela Nasreen; Ramakrishna, Seeram

2014-12-01

396

Morphology of zirconia synthesized hydrothermally from zirconium oxychloride  

SciTech Connect

This paper reports that monoclinic zirconia has been synthesized hydrothermally from zirconium oxychloride in the range 20--100 MPa, 250--650[degrees]C, for run duration from 20 to 100 h and in the presence of NaOH, Na[sub 2]CO[sub 3], Na[sub 2]SO[sub 4], NH[sub 4]F, HNO[sub 3], and H[sub 2]SO[sub 4] additives. Isometric, platelike, and elongated crystal morphologies were obtained depending on the additive. Both spherulitic and isolated textures were encountered with H[sub 2]SO[sub 4]. Growth of isometric crystals follows a general dissolution--precipitation mechanism. For H[sub 2]SO[sub 4], two growth steps were identified: an early spherulitic step followed by an isolated crystals step resulting from Ostwald ripening of preexisting spherulites. The formation of spherulites is consistent with the specific properties of the sulfuric hydrothermal medium.

Mottet, B.; Pichavant, M.; Beny, J.M. (Centre de Recherche sur la Synthese et la Chimie des Mineraux, 45 071 Orleanss Cedex 02 (France)); Alaary, J.A. (Secteur Elaboration des Materiaux, Centre de Recherches de Voreppe, 38 340 Voreppe (France))

1992-09-01

397

Long-term leaching behaviour of glasses containing zirconium  

NASA Astrophysics Data System (ADS)

Five borosilicate glasses containing up to 20% zirconium oxide and 10% non-radioactive fission products or lanthanum oxide (which simulates the behaviour of the actinides) were leached in stagnant distilled water at 20 ° C for 2 years. The leaching rates of Na, La, Mn, Cs and Mo varied with time and the chemical composition of the glass from 0.7 to 12, 0.006 to 0.14, 0.8 to 1.2, 0.4 to 0.8 and 8 to 25 mg/m 2/d respectively. The glasses which showed the beast short-term resistance do not have the best long-term resistance.

St.-Pierre, Jean; Zikovsky, L.

1984-08-01

398

Titanium-Zirconium-Nickel Alloy Inside Marshall's Electrostatic Levitator (ESL)  

NASA Technical Reports Server (NTRS)

This is a close-up of a sample of titanium-zirconium-nickel alloy inside the Electrostatic Levitator (ESL) vacuum chamber at NASA's Marshall Space Flight Center (MSFC). The ESL uses static electricity to suspend an object (about 3-4 mm in diameter) inside a vacuum chamber allowing scientists to record a wide range of physical properties without the sample contracting the container or any instruments, conditions that would alter the readings. Once inside the chamber, a laser heats the sample until it melts. The laser is then turned off and the sample cools, changing from a liquid drop to a solid sphere. Since 1977, the ESL has been used at MSFC to study the characteristics of new metals, ceramics, and glass compounds. Materials created as a result of these tests include new optical materials, special metallic glasses, and spacecraft components.

2003-01-01

399

Titanium-Zirconium-Nickel Alloy Inside Marshall's Electrostatic Levitator (ESL)  

NASA Technical Reports Server (NTRS)

This Photo, which appeared on the July cover of `Physics Today', is of the Electrostatic Levitator (ESL) at NASA's Marshall Space Flight Center (MSFC). The ESL uses static electricity to suspend an object (about 3-4 mm in diameter) inside a vacuum chamber allowing scientists to record a wide range of physical properties without the sample contracting the container or any instruments, conditions that would alter the readings. Once inside the chamber, a laser heats the sample until it melts. The laser is then turned off and the sample cools, changing from a liquid drop to a solid sphere. In this particular shot, the ESL contains a solid metal sample of titanium-zirconium-nickel alloy. Since 1977, the ESL has been used at MSFC to study the characteristics of new metals, ceramics, and glass compounds. Materials created as a result of these tests include new optical materials, special metallic glasses, and spacecraft components.

2003-01-01

400

Hydrogen absorption by zirconium alloys at high temperatures  

NASA Astrophysics Data System (ADS)

At high temperatures, e.g. during a hypothetical severe accident, zirconium and its alloys are not stable to other materials and to oxidising atmospheres. Exothermic reactions with steam cause the production of hydrogen which will be released to the atmosphere and, thus, endanger the containment or may be absorbed by the remaining metal. The hydrogen solubility in Zircaloy-4 and Zr-1Nb was measured in the temperature range of 1230-1730 K and at hydrogen partial pressures between 10 and 100 kPa. The parameters of the Sieverts constant were determined. No significant differences between the two alloys were observed. The hydrogen solubility of oxygen containing Zircaloy-4 decreases with increasing oxygen content.

Steinbrück, Martin

2004-08-01

401

Effect of yttrium on nucleation and growth of zirconium hydrides  

NASA Astrophysics Data System (ADS)

Addition of yttrium in zirconium causes precipitates of yttrium, which form two types of particles and are oxidized upon heat treatment. One type of particles with sub-micrometer scale sizes has a low population, whereas the other with nano scale sizes has a high population and cluster distribution. Owing to strong affinity of yttrium to hydrogen, the nanoparticles, mostly within the grains of the Zr-Y alloy, attract nucleation of hydrides at the clusters of the nanoparticles and cause preferential distribution of intragranular hydrides. In comparison with that of Zr, additional nanoparticles in the Zr-Y alloy impede further growth of hydride precipitates during hydriding. It is deduced that the impediment of growing hydride precipitates by the nanoparticles is developed during an auto-catalytic nucleation process, which leads to formation of thin and intragranular hydrides, favorable to mitigation of hydride embrittlement.

Li, Changji; Xiong, Liangyin; Wu, Erdong; Liu, Shi

2015-02-01

402

Simple spectrophotometric method for determination of zirconium or hafnium in selected molybdenum-base alloys.  

PubMed

A simple analytical procedure is described for determining zirconium or hafnium in molybdenum-base alloys by formation of the Arsenazo III complex of zirconium or hafnium in 9 M hydrochloric acid medium. The absorbance is measured at 670 nm. Molybdenum (10 mg), titanium (1 mg), and rhenium (10 mg) have no adverse effect. No prior separation is needed. The relative standard deviation is 1.3-2.7%. PMID:18961121

Dupraw, W A

1972-06-01

403

Acid-base properties of sorbents based on modified zirconium(IV) phosphates  

SciTech Connect

Modifying and doping syntheses are widely used to improve the reproducibility of ion-exchange properties and to increase the capacity of inorganic ion exchangers. Numerous examples of doping zirconium phosphate ion exchangers with cationic or anionic additives are known. The aim of this work was to investigate the acid-base properties of zirconium phosphates modified with anionic additives (phthalate and sulfosalicylate ions) in comparison with unmodified samples.

Bekrenev, A.V. [Research Center of Environmental Safety, St. Petersburg (Russian Federation); Pyartman, A.K. [St. Petersburg Institute of Technology (Russian Federation)

1995-11-01

404

Efficient UV-Emitting X-Ray Phosphors: Potassium Hafnium-Zirconium Phosphates  

E-print Network

Efficient UV-Emitting X-Ray Phosphors: Potassium Hafnium-Zirconium Phosphates K2Hf1-xZrx(PO4 Abstract Potassium hafnium-zirconium phosphates, K2Hf1-xZrx(PO4)2 and KHf2(1-x)Zr2x(PO4)3 are broad-band UV.e., those with emission less than 400 nm). Attention was given to hafnium-oxide based phosphors because HfO2

Li, Jing

405

Atomic Diffusion in the Uranium-50wt% Zirconium Nuclear Fuel System  

E-print Network

ATOMIC DIFFUSION IN THE URANIUM-50WT% ZIRCONIUM NUCLEAR FUEL SYSTEM A Thesis by DANIEL R. EICHEL Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... design concept. Image courtesy Lightbridge Corporation. ............................................... 2 Figure 2: Phase diagram for the binary zirconium-uranium system, showing the existence of the ? phase below 600?C for alloy compositions...

Eichel, Daniel

2013-06-17

406

Status of highly loaded uranium-zirconium hydride Low Enriched Uranium (LEU) fuel programs  

Microsoft Academic Search

The LEU uranium-zirconium hydride fuel has successfully completed all essential development testing and is offered commercially in both the 20 weight percent and 45 weight percent uranium concentrations for existing TRIGA reactors and as a conversion fuel for plate-type reactors. Several reactor facilities have already begun conversion to LEU uranium-zirconium hydride fuel. Currently, U-ZrH LEU fuel is in use in

1984-01-01

407

Graded selective coatings based on zirconium and titanium oxynitride  

NASA Astrophysics Data System (ADS)

The aim of this study was the development and characterization of transition metal oxynitride multilayers for optical applications. The reactive RF magnetron sputtering technique in rotation mode was used for stacking of zirconium oxynitride (ZrNO) and titanium oxynitride (TiNO) nanolayers. The depositions were carried out in a reactive Ar+N2+O2 atmosphere by sputtering titanium and zirconium targets. By means of different substrate rotation speeds, the bilayer period has been changed in the range 11-20 nm. A multilayer deposition rate increasing with the bilayer period decreasing has been evaluated. Structural, compositional, mechanical and optical analyses have been performed. The x-ray diffraction spectra confirmed the formation of a multilayer structure with a nitride formation prevalence. Non-abrupt interfaces between the layers and non-uniform chemical composition (chemical intermixing) have been detected by transmission electron microscope (TEM) observations. The gradient interface structure turns out to be an advantage for the improvement of the mechanical properties. Higher hardness values were calculated by the Chicot-Lesage and Jonsson-Hogmark models for TiNO/ZrNO multilayer compared with monolayer TiNO and ZrNO coatings. Also SIMS analysis has confirmed a compositional interface grading but also an increase in oxygen content with decreasing substrate rotation speed or similarly with decreasing deposition rate. Moreover, a tuning of the optical properties, going from metallic behaviour to dielectric with the decrease in the substrate rotation speed has been gained. The variation of the deposition rate allows a sort of 'regulation' of the oxygen incorporation with a precise tailoring of the optical properties. This result can be employed with the aim of depositing graded composition multilayer systems with a precise control of their optical selective wavelength properties. The improvement in the mechanical performance in graded oxynitride multilayer coatings would also allow an increase in the optical device lifetime.

Rizzo, A.; Signore, M. A.; Tapfer, L.; Piscopiello, E.; Cappello, A.; Bemporad, E.; Sebastiani, M.

2009-06-01

408

Ion beam mixing of chromium or zirconium films with sapphire  

SciTech Connect

Ion beam mixing of thin metallic films deposited on sapphire substrates was studied for chromium or zirconium films deposited on single crystalline {alpha}-Al{sub 2}0{sub 3} substrates. Evidence for the influence of equilibrium thermodynamic factors was sought by comparing the effects of bombarding with oxygen ions (300 and 1073 K) with those of neon ions (300 K). Thermodynamic calculations indicate that mixing might occur for Zr/sapphire at 1073 K but not at 300 K. Chromium/sapphire should not be mixed at either temperature. The implantation energy placed the peak oxygen concentration at the metal/sapphire interface in an attempt to maintain an equilibrium ratio of cations/anions and promote a radiation-induced chemical reaction across the interface. Rutherford backscattering-ion channeling measurements indicated that the widths of ``mixed`` regions were consistent with those predicted from ballistic considerations. Other experiments employed a heavier ion (krypton) as the mixing ion (300 K) in order to increase the mixing efficiency. Rutherford backscattering-ion channeling and x-ray photoelectron spectroscopy were used to determine the extent and nature of any interface modification. XPS results indicated that only metallic chromium (Cr{sup 0}) was present near the interface before and after irradiation with Kr at 300 K. Zirconium exhibited only the metallic state (Zr{sup 0}) in the as-deposited film but was present as both Zr{sup 0} and Zr{sup 4{plus}} after irradiation. Some metallic aluminum (AI{sup O}) was detected near the Zr/sapphire interface, suggesting that a local chemical reaction between Zr and the sapphire occurred during bombardment. No long-range material transport was detected for any experimental condition examined; the width of the ``mixed` region in each case was consistent with that expected for ballistic effects.

McHargue, C.J. [Tennessee Univ., Knoxville, TN (United States); Joslin, D.L.; White, C.W. [Oak Ridge National Lab., TN (United States); daSilva, M.F.; Alves, E. [National Inst. for Industrial Technology and Engineering, Sacavem (Portugal); Soares, J.C. [Lisbon Univ. (Portugal)

1995-12-31

409

Mechanical resistance of zirconium implant abutments: A review of the literature  

PubMed Central

The increase of aesthetic demands, together with the successful outcome of current implants, has renewed interest in the search for new materials with enough mechanical properties and better aesthetic qualities than the materials customarily used in implanto-prosthetic rehabilitation. Among these materials, zirconium has been used in different types of implants, including prosthetic abutments. The aim of the present review is to analyse current scientific evidence supporting the use of this material for the above mentioned purposes. We carried out the review of the literature published in the last ten years (2000 through 2010) of in vitro trials of dynamic and static loading of zirconium abutments found in the databases of Medline and Cochrane using the key words zirconium abutment, fracture resistance, fracture strength, cyclic loading. Although we have found a wide variability of values among the different studies, abutments show favourable clinical behaviour for the rehabilitation of single implants in the anterior area. Such variability may be explained by the difficulty to simulate daily mastication under in vitro conditions. The clinical evidence, as found in our study, does not recommend the use of implanto-prosthetic zirconium abutments in the molar area. Key words: Zirconium abutment, zirconium implant abutment, zirconia abutment, fracture resistance, fracture strength, cyclic loading. PMID:22143702

Vaquero-Aguilar, Cristina; Torres-Lagares, Daniel; Jiménez-Melendo, Manuel; Gutiérrez-Pérez, José L.

2012-01-01

410

The Indigenous World, 1996-97 = El Mundo Indigena, 1996-97.  

ERIC Educational Resources Information Center

This annual publication (published separately in English and Spanish) examines political, legal, social, and educational issues concerning indigenous peoples around the world during 1996-97. Part I highlights news events and ongoing situations in specific countries. In North America, these include threats of proposed oil drilling on sacred sites…

Erni, Christian, Ed.

411

Actinide partitioning from actual ICPP dissolved zirconium calcine using the TRUEX solvent  

SciTech Connect

The TRansUranic EXtraction process (TRUEX), as developed by E.P. Horwitz and coworkers at Argonne National Laboratory (ANL), is being evaluated as a TRU extraction process for Idaho Chemical Processing Plant (ICPP) wastes. A criteria that must be met during this evaluation, is that the aqueous raffinate must be below the 10 nCi/g limit specified in 10 CFR 61.55. A test was performed where the TRUEX solvent (0.2 M octyl(phenyl)-N-N-diisobutyl-carbamoylmethyl-phosphine oxide (CMPO), and 1.4 M tributylphosphate (TBP) in an Isopar-L diluent) was contacted with actual ICPP dissolved zirconium calcine. Two experimental flowsheets were used to determine TRU decontamination factors, and TRU, Zr, Fe, Cr, and Tc extraction, scrub, and strip distribution coefficients. Results from these two flowsheets show that >99.99% of the TRU alpha activity was removed from the acidic feed after three contacts with the TRUEX solvent (fresh solvent being used for each contact). The resulting aqueous raffinate solution contained an approximate TRU alpha activity of 0.02 nCi/g, which is well below the non-TRU waste limit of 10 nCi/g specified in 10 CFR 61.55. Favorable scrub and strip distribution coefficients were also observed for Am-241, Pu-238, and Pu-239, indicating the feasibility of recovering these isotopes from the TRUTEX solvent. A solution of 0.04 M 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) in 0.04 M HNO{sub 3} was used to successfully strip the TRUs from the TRUEX solvent. The results of the test using actual ICPP dissolved zirconium calcine, and subsequent GTM evaluation, show the feasibility of removing TRUs from the dissolved zirconium calcine with the TRUEX solvent and the deleterious effects zirconium poses with the ICPP zirconium calcine waste. Test results using actual ICPP zirconium calcine reveal the necessity of preventing zirconium from following the TRUs.

Brewer, K.N.; Herbst, R.S.; Tranter, T.J. [and others

1995-05-01

412

Synthesis and liquid crystal phase transitions of zirconium phosphate disks  

NASA Astrophysics Data System (ADS)

Solvent-mediated self-assembly of nanoparticles is an effective and efficient way for the bottom-up organization of functional structures. The primary object of this work is to build up a model system for the study of suspensions of disk-shaped nanoparticles, and use it for the study of self-assembly and discotic liquid crystal phase transitions of discotic particles. The work was introduced by the control over the size and polydispersity of zirconium phosphate (ZrP) disks through synthesis. Systematic experiments revealed that regular-shaped alpha-zirconium phosphate crystalline disks with a size-to-thickness ratio from 1 to 50 and size polydispersity as low as 0.2 can be obtained through hydrothermal treatment in 3 M to 15 M phosphoric acid solutions. Transmission and scanning electron micrographs revealed that the growth of the disks is mediated by oriented attachment, which happened continuously throughout the hydrothermal treatment between various sized disks. Ostwald ripening is effective in improving the regularity of the shape of the disks, especially under prolonged hydrothermal treatment. Under the microwave assisted hydrothermal conditions, the rate of attachment on the flat surfaces of the disks is accelerated, which leads to the formation of the column-shaped crystals. With the ability to adjust the size, aspect ratio, and polydispersity of ZrP disks, the study on self-assembly behavior and the discotic liquid crystal phases was enabled. Firstly, liquid crystal phases of aqueous suspensions of ZrP disks were investigated. Iridescent smectic phase and the critical points of phase transitions were found. Moreover, monolayer ZrP nanosheets with extremely high aspect ratio, which were achieved by exfoliating the ZrP crystals, were also used in this study. The high aspect ratio of nanosheets produces a laminar phase at low nanosheet concentration. Chiral liquid crystal phases were demonstrated when increased the concentration of the nanosheets. The competition between the chirality and layering leads to twisted and layered structures. For the final part, solvent-mediated self-assembly of disks and nanosheets via undulation of liquid crystal phases showed an interesting approach for bottom-up design of functional nano-structures.

Shuai, Min

413

Highly enantioselective zirconium-catalyzed cyclization of aminoalkenes.  

PubMed

Aminoalkenes are catalytically cyclized in the presence of cyclopentadienylbis(oxazolinyl)borato group 4 complexes {PhB(C5H4)(Ox(R))2}M(NMe2)2 (M = Ti, Zr, Hf; Ox(R) = 4,4-dimethyl-2-oxazoline, 4S-isopropyl-5,5-dimethyl-2-oxazoline, 4S-tert-butyl-2-oxazoline) at room temperature and below, affording five-, six-, and seven-membered N-heterocyclic amines with enantiomeric excesses of >90% in many cases and up to 99%. Mechanistic investigations of this highly selective system employed synthetic tests, kinetics, and stereochemistry. Secondary aminopentene cyclizations require a primary amine (1-2 equiv vs catalyst). Aminoalkenes are unchanged in the presence of a zirconium monoamido complex {PhB(C5H4)(Ox(4S-iPr,Me2))2}Zr(NMe2)Cl or a cyclopentadienylmono(oxazolinyl)borato zirconium diamide {Ph2B(C5H4)(Ox(4S-iPr,Me2))}Zr(NMe2)2. Plots of initial rate versus [substrate] show a rate dependence that evolves from first-order at low concentration to zero-order at high concentration, and this is consistent with a reversible substrate-catalyst interaction preceding an irreversible step. Primary kinetic isotope effects from substrate conversion measurements (k'obs((H))/k'obs((D)) = 3.3 ± 0.3) and from initial rate analysis (k2((H))/k2((D)) = 2.3 ± 0.4) indicate that a N-H bond is broken in the turnover-limiting and irreversible step of the catalytic cycle. Asymmetric hydroamination/cyclization of N-deutero-aminoalkenes provides products with higher optical purities than obtained with N-proteo-aminoalkenes. Transition state theory, applied to the rate constant k2 that characterizes the irreversible step, provides activation parameters consistent with a highly organized transition state (?S(++) = -43(7) cal·mol(-1) K(-1)) and a remarkably low enthalpic barrier (?H(++) = 6.7(2) kcal·mol(-1)). A six-centered, concerted transition state for C-N and C-H bond formation and N-H bond cleavage involving two amidoalkene ligands is proposed as most consistent with the current data. PMID:23631736

Manna, Kuntal; Everett, William C; Schoendorff, George; Ellern, Arkady; Windus, Theresa L; Sadow, Aaron D

2013-05-15

414

Electrospun poly (vinyl alcohol)/ alpha-zirconium phosphate nanocomposite fibers  

NASA Astrophysics Data System (ADS)

Poly (vinyl alcohol) (PVA)/alpha-zirconium phosphate (ZrP) polymer nanocomposite (PNC) fibers were successfully prepared via the simple and low-cost electrospinning process. ZrP nanoparticles with two different dimensions, i.e., ZrP-500 with a lateral dimension of ca. 320 nm and an aspect ratio of ca. 500, and ZrP-1500 with a lateral dimension of ca. 950 nm and an aspect ratio of ca. 1500, were utilized to illustrate the size effect on the electrospun nanofibers. In order to obtain defect-free, uniform polymer nanocomposite fibers, a number of parameters including polymer concentration, feed rate, applied voltage and working distance between the needle tip and the fiber collecting substrate were investigated. Scanning electron microscopy (SEM) morphological analysis showed smooth and nonwoven electrospun nanofiber mat. Strong intermolecular interactions between the PVA matrix and the included ZrP nanofillers were revealed by the attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The incorporation of ZrP nanofillers drastically improved the thermal stability of the PNC fibers. TGA results demonstrated a clear thermal stability dependence on the aspect ratio of the crystalline ZrP nanofillers. The degradation temperature was increased by 90 °C for the ZrP-1500 and 60 °C for ZrP-500 when the loading level was increased from 1% to 5%. Furthermore, the viscoelastic properties of the PNC solutions were studied by rheometer.

Lizu, Monira

415

Synthesis and Characterization of Zirconium Tungstate Ultra-Thin Fibers  

SciTech Connect

This study reports an innovative method of electrospinning followed by pyrolysis to synthesize zirconium tungstate (ZrW2O8), a material with negative coefficient of thermal expansion (CTE), in ultra-thin fiber form. Morphologies and microstructures of the as-electrospun precursor fibers, the heat-treated intermediate fibers, and the final ZrW2O8 ultra-thin fibers were characterized by SEM, XRD, and TEM. The ZrW2O8 ultra-thin fibers had diameters in the sub-micrometer range with aspect ratios larger than 100; these fibers were polycrystalline, and consisted of single crystalline ZrW2O8 crystallites with sizes of 30-50 nm and surface roughness of several nanometers. The ZrW2O8 ultra-thin fibers are expected to outperform spherically, cylindrically, and/or irregularly shaped polycrystalline ZrW2O8 particles for the development of composites with precisely controlled CTEs. Additionally, this reported method could be utilized as a general approach to convert nano-scaled inorganic particles into fibers.

Zhang, Lifeng [South Dakota School of Mines and Technology; Howe, Jane Y [ORNL; Fong, Hao [South Dakota School of Mines and Technology; Zhang, Yan [Anhui Normal University, People's Republic of China

2009-01-01

416

Surface modification of Zircaloy-4 substrates with nickel zirconium intermetallics  

NASA Astrophysics Data System (ADS)

Surfaces of Zircaloy-4 (Zr-4) substrates were modified with nickel-zirconium (NiZr) intermetallics to tailor oxidation performance for specialized applications. Surface modification was achieved by electroplating Zr-4 substrates with nickel (Ni) and then performing thermal treatments to fully react the Ni plating with the substrates, which resulted in a coating of NiZr intermetallics on the substrate surfaces. Both plating thickness and thermal treatment were evaluated to determine the effects of these fabrication parameters on oxidation performance and to identify an optimal surface modification process. Isothermal oxidation tests were performed on surface-modified materials at 290°, 330°, and 370 °C under a constant partial pressure of oxidant (i.e., 1 kPa D2O in dry Ar at 101 kPa) for 64 days. Test results revealed an enhanced, transient oxidation rate that decreased asymptotically toward the rate of the Zr-4 substrate. Oxidation kinetics were analyzed from isothermal weight gain data, which were correlated with microstructure, hydrogen pickup, strength, and hardness.

Luscher, Walter G.; Gilbert, Edgar R.; Pitman, Stan G.; Love, Edward F.

2013-02-01

417

Zirconium and hafnium Salalen complexes in isospecific polymerisation of propylene.  

PubMed

The activity of dibenzylzirconium and dibenzylhafnium Salalen complexes in polymerisation of propylene with MAO as a cocatalyst is described. Three Salalen ligand precursors combining a bulky alkyl group (1-adamantyl) on the imine-side phenol and electron withdrawing halo groups of different sizes on the amine-side phenol were explored. All metal complexes were obtained as single diastereomers. An X-ray crystallographic structure of a hafnium complex of an additional ligand carrying the combination of tert-butyl and chloro substituted phenolates, 4-Hf, revealed a fac-mer wrapping of the Salalen ligand around the metal centre. All complexes led to active catalysts in propylene polymerisation and to isotactic polypropylene of high regioregularity. The zirconium complexes led to polypropylene having molecular weights of Mw = 132,000-200,000 and isotacticities of [mmmm] = 65.7-75.0%. The hafnium complexes led to polypropylene of higher molecular weights of Mw = 375,000-520,000 and higher stereoregularities of [mmmm] = 80.6-89.3%, the highest isotacticity obtained with 3-Hf. PMID:23471354

Press, Konstantin; Venditto, Vincenzo; Goldberg, Israel; Kol, Moshe

2013-07-01

418

Structural and electrical properties of zirconium doped yttrium oxide nanostructures  

NASA Astrophysics Data System (ADS)

A synthetic process for the formation of ZrxY1-xOy nanostructures is demonstrated by the reaction of yttrium nitrate hexahydrate with zirconium propoxide. The reactions are carried out at temperature 60°C and pressure 0.1 MPa. The energy dispersive X-ray (EDX) spectroscopy measurements confirm formation of ZrxY1-xOy nanostructures and the presence of carbonate and hydroxide species which are removed after high temperature anneals. It was found that the oxygen pressure during synthesis plays a determinant role on the structural properties of the nanostructure. This effect is further studied by atomic force microscopy (AFM) measurements and scanning electron microscope (SEM), which showed the formation of an isotopically organized structure. X-ray diffraction (XRD) measurement reveals that these changes in the nanostructural efficiency are associated with structural and compositional changes among the substrate. The dielectric constant as measured by the capacitance-voltage (C-V) technique is estimated to be around 39.05. C-V measurements taken at 1 MHz show the maximum capacitance for the Zr0.05Y0.95Oy film. The leakage current densities were below 10-5 A/cm2 for the Zr0.05Y0.95Oy film.

Bahari, Ali; Ebrahimzadeh, Masoud; Gholipur, Reza

2014-04-01

419

Fracture Resistance of a Zirconium Alloy with Reoriented Hydrides  

NASA Astrophysics Data System (ADS)

Zirconium alloy cladding materials typically contain circumferential hydrides that may be reoriented to align along the radial direction when the cladding tubes are heated above and then cooled below the solvus temperature. The objectives of this study were to investigate the critical stress levels required to cause hydride reorientation (HRT) and to characterize the fracture resistance of Zircaloy-2 after hydride reorientation. HRT heat-treatment was performed on hydrogen-charged Zircaloy-2 specimens at 593 K (320 °C) or 623 K (350 °C) for 1 to 2 hours, followed by cooling to 473 K (200 °C). Fracture testing was conducted on hydride-reoriented three-point bend specimens at 473 K (200 °C) using an in situ loading stage inside a scanning electron microscope. Direct observations indicated that the reoriented hydrides, which ranged from ?1 to 22 ?m in lengths, were more prone to fracture at larger sizes (>10 ?m) compared to smaller sizes (<0.5 ?m). The reoriented hydrides reduced fracture resistance through a void nucleation, growth, and coalescence process at the crack tip. The resulting crack-resistance curves for Zircaloy-2 with reoriented hydrides decrease from 38 to 21 MPa(m)1/2 with increasing hydrogen contents from 51 to 1265 wt ppm hydrogen.

Chan, Kwai S.; He, Xihua; Pan, Yi-Ming

2015-01-01

420

The effect of zirconium implantation on the structure of sapphire  

SciTech Connect

The effect of zirconium implantation on the structure of sapphire was investigated by 175 keV Zr implantation at room temperature to a fluence of 4 1016 ions/cm2 into sapphire single crystals. Samples were examined by several experimental techniques: Rutherford backscattering spectroscopy along a channeling direction (RBS-C), electron-energy loss spectroscopy (EELS), and Z-contrast images obtained in an aberration-corrected scanning transmission electron microscope. Range and deposited energy were simulated with SRIM-2008.04. The Z-contrast images from transmission electron microscope indicated: a near surface damaged layer ~30 nm thick, a subsurface region exhibiting "random" de-channeling ~52 nm thick, and a deeper damaged, crystalline zone ~64 nm thick. The RBS-C spectra confirmed the presence of these three regions. The two damaged regions contained high concentrations of as yet unresolved defect clusters. The intermediate region contained Zr-clusters embedded in an "amorphous" matrix that exhibited short-range order corresponding to -Al2O3, i.e., a defective spinel structure. The EELS measurements show that the amorphous region is deficient in oxygen.

Sina, Younes [University of Tennessee, Knoxville (UTK); McHargue, Carl J [University of Tennessee, Knoxville (UTK); Duscher, Gerd [University of Tennessee, Knoxville (UTK); Zhang, Yanwen [ORNL

2012-01-01

421

Characterization of precipitates in a niobium-zirconium-carbon alloy  

NASA Technical Reports Server (NTRS)

A niobium alloy with 1 percent zirconium and 0.063 percent carbon by weight was investigated in the as-rolled and annealed conditions, and after high-temperature (1350 and 1400 K) exposure with and without an applied stress. In the as-rolled and annealed conditions, large metastable carbides were observed in addition to a regular distribution of small particles. During the high-temperature exposure, the majority of the large carbides were dissolved and a more stable carbide phase formed. This finely dispersed phase had a composition determined to be approximately 70 percent ZrC and approximately 30 percent NbC and showed some evidence of an orientation relationship with the matrix. The precipitates appeared to coarsen slightly after approximately 5000 hr exposure in the presence of an applied stress resulted in a decrease in the size and in the interparticle spacing of the stable precipitates. However, the composition of the precipitate phase and its ability to pin dislocations were not affected by the temperature or stress conditions.

Grobstein, T. L.; Titran, R. H.

1986-01-01

422

Effects of Fast Neutron Irradiation on Zirconium Carbide  

SciTech Connect

High-purity zone refined zirconium carbide has been fast neutron irradiated in the dose and temperature range of 1-10 x 10{sup 25} N/m{sup 2} (E > 0.1 MeV) and 635-1480 C, respectively. Non-irradiated and as-irradiated properties were measured including the lattice parameter, hardness and elastic modulus as determined through nano-indentation, thermal conductivity, and indentation fracture toughness. The effects of neutron irradiation on the microstructure were also determined though using transmission electron microscopy. The general finding of this paper, limited to this particular zone refined ZrC of nominal C/Zr ratio of 0.93, is that this ceramic is quite stable under neutron irradiation in the temperature and dose range studied. Measurement of lattice parameter before and after irradiation indicated a lack of significant crystalline strain due to irradiation. Only modest changes were observed in the mechanical properties of hardness, elastic modulus, and indentation fracture toughness. The thermal conductivity underwent a slight reduction near 1000 C irradiation, though was essentially unchanged for 1300-1480 C irradiation. Transmission electron microscopy revealed black-spot-type defects (likely Frank or other small loops) for irradiation at 670 C, maturing to faulted Frank loops at 1280 C. As the irradiation temperature increased from 1280 C to the highest irradiation temperature, of 1496 C, a transition to prismatic loops occurs.

Snead, Lance Lewis [ORNL; Katoh, Yutai [ORNL; Kondo, Sosuke [ORNL

2010-01-01

423

Characterization of zirconium thin films deposited by pulsed laser deposition  

NASA Astrophysics Data System (ADS)

Zirconium (Zr) thin films deposited on Si (100) by pulsed laser deposition (PLD) at different pulse repetition rates are investigated. The deposited Zr films exhibit a polycrystalline structure, and the X-ray diffraction (XRD) patterns of the films show the ? Zr phase. Due to the morphology variation of the target and the laser—plasma interaction, the deposition rate significantly decreases from 0.0431 Å/pulse at 2 Hz to 0.0189 Å/pulse at 20 Hz. The presence of droplets on the surface of the deposited film, which is one of the main disadvantages of the PLD, is observed at various pulse repetition rates. Statistical results show that the dimension and the density of the droplets increase with an increasing pulse repetition rate. We find that the source of droplets is the liquid layer formed under the target surface. The dense nanoparticles covered on the film surface are observed through atomic force microscopy (AFM). The root mean square (RMS) roughness caused by valleys and islands on the film surface initially increases and then decreases with the increasing pulse repetition rate. The results of our investigation will be useful to optimize the synthesis conditions of the Zr films.

Liu, Wei; Wan, Jing-Ping; Cai, Wu-Peng; Liang, Jian-Hua; Zhou, Xiao-Song; Long, Xing-Gui

2014-09-01

424

SURFACE MODIFICATION OF ZIRCALOY-4 SUBSTRATES WITH NICKEL ZIRCONIUM INTERMETALLICS  

SciTech Connect

Surfaces of Zircaloy-4 (Zr-4) substrates were modified with nickel-zirconium (NiZr) intermetallics to tailor oxidation performance for specialized applications. Surface modification was achieved by electroplating Zr-4 substrates with nickel (Ni) and then performing thermal treatments to fully react the Ni plating with the substrates, which resulted in a coating of NiZr intermetallics on the substrate surfaces. Both plating thickness and thermal treatment were evaluated to determine the effects of these fabrication parameters on oxidation performance and to identify an optimal surface modification process. Isothermal oxidation tests were performed on surface-modified materials at 290°, 330°, and 370°C under a constant partial pressure of oxidant (i.e., 1 kPa D2O in dry Ar at 101 kPa) for 64 days. Test results revealed an enhanced, transient oxidation rate that decreased asymptotically toward the rate of the Zr-4 substrate. Oxidation kinetics were analyzed from isothermal weight gain data, which were correlated with microstructure, hydrogen pickup, strength, and hardness.

Luscher, Walter G.; Gilbert, Edgar R.; Pitman, Stan G.; Love, Edward F.

2013-02-01

425

Zirconium phosphate waste forms for low-temperature stabilization of cesium-137-containing waste streams  

SciTech Connect

Novel chemically bonded phosphate ceramics are being developed and fabricated for low-temperature stabilization and solidification of waste streams that are not amenable to conventional high-temperature stabilization processes because volatiles are present in the wastes. A composite of zirconium-magnesium phosphate has been developed and shown to stabilize ash waste contaminated with a radioactive surrogate of {sup 137}Cs. Excellent retainment of cesium in the phosphate matrix system was observed in Toxicity Characteristic Leaching Procedure tests. This was attributed to the capture of cesium in the layered zirconium phosphate structure by intercalation ion-exchange reaction. But because zirconium phosphate has low strength, a novel zirconium/magnesium phosphate composite waste form system was developed. The performance of these final waste forms, as indicated by compression strength and durability in aqueous environments, satisfy the regulatory criteria. Test results indicate that zirconium-magnesium-phosphate-based final waste forms present a viable technology for treatment and solidification of cesium-contaminated wastes.

Singh, D.; Wagh, A.S.; Tlustochowicz

1996-04-01

426

Zirconium-based alloys, nuclear fuel rods and nuclear reactors including such alloys, and related methods  

DOEpatents

Zirconium-based metal alloy compositions comprise zirconium, a first additive in which the permeability of hydrogen decreases with increasing temperatures at least over a temperature range extending from 350.degree. C. to 750.degree. C., and a second additive having a solubility in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. At least one of a solubility of the first additive in the second additive over the temperature range extending from 350.degree. C. to 750.degree. C. and a solubility of the second additive in the first additive over the temperature range extending from 350.degree. C. to 750.degree. C. is higher than the solubility of the second additive in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. Nuclear fuel rods include a cladding material comprising such metal alloy compositions, and nuclear reactors include such fuel rods. Methods are used to fabricate such zirconium-based metal alloy compositions.

Mariani, Robert Dominick

2014-09-09

427

Synthesis of zirconium tungstate-zirconia core-shell composite particles  

SciTech Connect

Highlights: {yields} ZrW{sub 2}O{sub 8}-ZrO{sub 2} core-shell particles to offer solutions for sintering problems. {yields} Core synthesis by a precursor based on tungstic acid and zirconium acetate. {yields} Shell phase by urea hydrolysis in the presence of zirconium ions. {yields} [Urea]/[ZrOCl{sub 2}] ratio controls the rate of shell precursor precipitation. -- Abstract: In this work, ZrW{sub 2}O{sub 8}-ZrO{sub 2} core-shell composite particles were synthesized. ZrW{sub 2}O{sub 8} that was used in the core is a material with negative coefficient of thermal expansion, and it was synthesized from a high-pH precursor based on use of tungstic acid and zirconium acetate. Shell layer was composed of ZrO{sub 2} nanocrystallites and precipitated from an aqueous solution by urea hydrolysis. While volume of the shell was effectively controlled by the initial zirconium ion concentration in the solutions, the rate of precipitation was a function of the ratio of initial concentrations of urea to zirconium ions. It is hypothesized that isolation of the ZrW{sub 2}O{sub 8} within a layer of ZrO{sub 2}, will be a key element in solving problems associated with reactivity of ZrW{sub 2}O{sub 8} towards other components in sintering of ceramic-ceramic composites with tuned or zero thermal expansion coefficient.

Khazeni, Nasser, E-mail: khazeni.n@gmail.com [Chemical Engineering Department, Middle East Technical University, Ankara 06531 (Turkey)] [Chemical Engineering Department, Middle East Technical University, Ankara 06531 (Turkey); Mavis, Bora, E-mail: bmavis@hacettepe.edu.tr [Mechanical Engineering Department, Hacettepe University, Beytepe Ankara 06800 (Turkey)] [Mechanical Engineering Department, Hacettepe University, Beytepe Ankara 06800 (Turkey); Guenduez, Guengoer, E-mail: ggunduz@metu.edu.tr [Chemical Engineering Department, Middle East Technical University, Ankara 06531 (Turkey)] [Chemical Engineering Department, Middle East Technical University, Ankara 06531 (Turkey); Colak, Uner, E-mail: ucolak@hacettepe.edu.tr [Nuclear Engineering Department, Hacettepe University, Beytepe Ankara 06800 (Turkey)] [Nuclear Engineering Department, Hacettepe University, Beytepe Ankara 06800 (Turkey)

2011-11-15

428

Pore-size tunable mesoporous zirconium organophosphonates with chiral L-proline for enzyme adsorption.  

PubMed

Mesoporous zirconium organophosphonates with a tunable mesopore (pore diameter: from 4.8 to 16.3 nm) were synthesized through co-condensation of ZrCl4 and 1-phosphomethylproline (H3PMP) with the aid of organic additives in the presence of an anionic surfactant (sodium dodecyl sulfate) under weak acidic conditions. The organic additives, tetrahydrofuran, can effectively strengthen the assembly of ZrCl4 and H3PMP around the surfactant micelles through decreasing the hydrolysis and condensation rate of ZrCl4. The results of the N2 sorption isotherm and SEM image show that zirconium phosphate with a bimodal structure is formed by calcination of mesoporous zirconium organophosphonate. Mesoporous zirconium organophosphonates can effectively adsorb lysozyme (Lz) and papain, and the adsorption equilibrium for Lz can be reached within 30 min. The adsorption capacity for Lz and papain can reach as high as 438 and 297 mg/g, respectively. Furthermore, Lz adsorbed on mesoporous zirconium organophosphonates can retain its structural conformation as in its free state, and no leaching of Lz from the solid was observed when shaking the Lz-loaded solid in a buffer solution. Also, the existence of L-proline in the mesopore could help the adsorption of papain at a pH value lower than the pI of papain. PMID:17696427

Shi, Xin; Liu, Jian; Li, Congming; Yang, Qihua

2007-09-17

429

Computational Design of Metal-Organic Frameworks Based on Stable Zirconium Building Units for Storage and Delivery of Methane  

E-print Network

between 65 and 5.8 bar is 167 cc(STP)/cc (0.215 g/g), the highest among zirconium-based MOFs. HighComputational Design of Metal-Organic Frameworks Based on Stable Zirconium Building Units-organic framework (MOF) with high volumetric deliverable capacity for methane was synthesized after being identified

430

Hartree-Fock-Bogoliubov calculations in coordinate space: Neutron-rich sulfur, zirconium, cerium, and samarium isotopes  

E-print Network

Hartree-Fock-Bogoliubov calculations in coordinate space: Neutron-rich sulfur, zirconium, cerium study the properties of neutron-rich zirconium 102,104 Zr , cerium 152 Ce , and samarium 158,160 Sm of nuclear iso- topes still to be explored with new radioactive ion beam facilities [1]. Another limit

Teran, Edgar

431

Role of p97/VCP (Cdc48) in genome stability.  

PubMed

Ubiquitin-dependent molecular chaperone p97, also known as valosin-containing protein (VCP) or Cdc48, is an AAA ATPase involved in protein turnover and degradation. p97 converts its own ATPase hydrolysis into remodeling activity on a myriad of ubiquitinated substrates from different cellular locations and pathways. In this way, p97 mediates extraction of targeted protein from cellular compartments or protein complexes. p97-dependent protein extraction from various cellular environments maintains cellular protein homeostasis. In recent years, p97-dependent protein extraction from chromatin has emerged as an essential evolutionarily conserved process for maintaining genome stability. Inactivation of p97 segregase activity leads to accumulation of ubiquitinated substrates on chromatin, consequently leading to protein-induced chromatin stress (PICHROS). PICHROS directly and negatively affects multiple DNA metabolic processes, including replication, damage responses, mitosis, and transcription, leading to genotoxic stress and genome instability. By summarizing and critically evaluating recent data on p97 function in various chromatin-associated protein degradation processes, we propose establishing p97 as a genome caretaker. PMID:23641252

Vaz, Bruno; Halder, Swagata; Ramadan, Kristijan

2013-01-01

432

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

2012-10-01

433

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

2010-10-01

434

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

2013-10-01

435

46 CFR 97.37-50 - Ventilation alarm failure.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

2011-10-01

436

40 CFR 97.387 - Change in regulatory status.  

Code of Federal Regulations, 2011 CFR

...CAIR NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change...status. (a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then...

2011-07-01

437

40 CFR 97.387 - Change in regulatory status.  

Code of Federal Regulations, 2010 CFR

...CAIR NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change...status. (a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then...

2010-07-01

438

29 CFR 97.51 - Later disallowances and adjustments.  

Code of Federal Regulations, 2010 CFR

29 ? Labor ? 1 ? 2010-07-01 ? 2010-07-01 ? true ? Later disallowances and adjustments. ? 97.51 ? Section 97.51 ? Labor ? Office of the Secretary of Labor ? UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS ? After-The-Grant Requirements ?...

2010-07-01

439

President's Address Geoscience for the Needs of Canadians 97  

E-print Network

President's Address Geoscience for the Needs of Canadians 97 L.H. Thorleifson Series Igneous Rock 31 NUMÃ?RO 3 GEOSCIENCE CANADA JOURNAL OF THE GEOLOGICAL ASSOCIATION OF CANADA JOURNAL DE L'ASSOCIATION GÃ?OLOGIQUE DU CANADA #12;GEOSCIENCE CANADA Volume 31 Number 3 September 2004 97 PRESIDENTIAL ADDRESS L. HL

440

McNU'97 Symposium on Mechanics of Composites  

E-print Network

. Experimental papers dealt with testing and modeling of high strain rate behavior, interlaminar fracturePreface McNU'97 Symposium on Mechanics of Composites This issue of the journal consists of a selected list of papers presented at the Symposium on Mechanics of Composites of the McNU'97 Joint ASME

Masud, Arif

441

7 CFR 29.97 - Who shall pass upon appeals.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Who shall pass upon appeals. 29.97 Section 29...Regulations Appeal § 29.97 Who shall pass upon appeals. Appeals shall be passed...two or more appeal inspectors may jointly pass upon an appeal. The Division may...

2010-01-01

442

Hypersensitivity pneumonitis and exposure to zirconium silicate in a young ceramic tile worker.  

PubMed

We describe a nonsmoking ceramic tile worker 25 yr of age who developed a worsening dry cough and dyspnea after 3.5 yr as a sorter and glazer of tiles. Open lung biopsy revealed an intense granulomatous interstitial pneumonia with mild fibrosis, compatible with hypersensitivity pneumonitis, and numerous very small birefringent crystals around the terminal airways and occasionally in granulomas. Pulmonary particle analysis revealed an inhaled dust burden nearly 100-fold the normal background level, mainly consisting of clay minerals and zirconium silicate. The patient had no history or clinical or laboratory findings suggesting any organic etiologic agent. A sarcoid granulomatosis type of chronic pulmonary hypersensitivity reaction is known after long-term exposure to zirconium, but this case demonstrates that zirconium can also cause an acute and fulminant allergic alveolitislike hypersensitivity reaction. PMID:8214930

Liippo, K K; Anttila, S L; Taikina-Aho, O; Ruokonen, E L; Toivonen, S T; Tuomi, T

1993-10-01

443

Hydrogen Embrittlement in Zirconium: a Quasi-Continuum Density Functional Theory Study  

NASA Astrophysics Data System (ADS)

The hydrogen embrittlement in Zirconium becomes a very important and emergent issue for academia, industry and policy makers as a result of the Japan nuclear accident. The hydride formation, diffusion and embrittlement in zircolay will impact dramatically on the development of advanced nuclear energy systems, the life time extension of the current nuclear fleet and dry storage of spent nuclear fuel. Quasi-Continuum Density Functional Theory (QCDFT) is a powerful concurrent multiscale method based entirely on density functional theory (DFT) and allows quantum simulations of materials properties of a large system with billions of atoms. Using QCDFT modeling, we found that the presents of hydrogen at the cracktip of zirconium, both on crack surface and in-bulk, will form zirconium hydrides and embrittle the system. The concentration of hydrogen and orientation of crack plays important roles in such embrittlement. The mechanism of hydrogen embrittlement under various loading conditions will be discussed.

Peng, Q.

2012-02-01

444

Theoretical study of the reaction between 2,2???,4???-trihydroxyazobenzene-5-sulfonic acid and zirconium  

USGS Publications Warehouse

Zirconium reacts with 2,2???,4???-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 m?? are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.

Fletcher, M.H.

1960-01-01

445

Simulating the corrosion of zirconium alloys in the water coolant of VVER reactors  

NASA Astrophysics Data System (ADS)

A model for predicting the corrosion of cladding zirconium alloys depending on their composition and operating conditions is proposed. Laws of thermodynamics and chemical kinetics of the reactions through which the multicomponent zirconium alloy is oxidized in the reactor coolant constitute the physicochemical heart of the model. The developed version of the model is verified against the results obtained from tests of fuel rod claddings made of commercial-grade and experimental zirconium alloys carried out by different researchers under autoclave and reactor conditions. It is shown that the proposed model adequately describes the corrosion of alloys in coolants used at nuclear power stations. It is determined that, owing to boiling of coolant and its acidification in a VVER-1200 reactor, Zr-1% Nb alloys with additions of iron and oxygen must be more resistant to corrosion than the commercial-grade alloy E110.

Kritskii, V. G.; Berezina, I. G.; Motkova, E. A.

2013-07-01

446

Ion processing of zirconium ceramics by high-power pulsed beams  

NASA Astrophysics Data System (ADS)

Modification of the structural phase state of the surface layer of zirconium ceramics irradiated by high-power pulsed beams of carbon ions at a pulse energy density of 3 J/cm2 is revealed using X-ray phase analysis and scanning electron microscopy. The analysis of roentgenograms indicates efficient formation of the high-temperature cubic modification of zirconium dioxide. The study of the depth distribution of oxygen ions using the secondary ion mass spectroscopy yields deficit of oxygen in the surface layer of the irradiated ceramics. A violation of the oxygen stoichiometry leads to a significant (by several orders of magnitude) increase in the conductivity of the samples under study. Mechanical characteristics (microhardness, nanohardness, and Young modulus) of the zirconium ceramics are determined after processing with high-power pulsed beams.

Ghyngazov, S. A.; Vasil'ev, I. P.; Surzhikov, A. P.; Frangulyan, T. S.; Chernyavskii, A. V.

2015-01-01

447

Review of Cernox™ (Zirconium Oxy-Nitride) Thin-Film Resistance Temperature Sensors  

NASA Astrophysics Data System (ADS)

Cernox™ resistance thermometers were commercially introduced in 1993. The Cernox™ temperature-sensing element is fabricated from zirconium reactively sputtered in a nitrogen-oxygen atmosphere. The resulting thin film is comprised of conducting zirconium nitride embedded within a zirconium oxide nonconducting matrix. This material has a negative temperature coefficient of resistance making it useful as a temperature sensor. The ratio of conducting to nonconducting material can be varied to tailor the sensor to a given temperature range. A single device can be fabricated for use from below 0.3 K to 420 K. Cernox™ temperature sensors possess many attributes desirable in a temperature sensor including high sensitivity, excellent short-term and long-term stability, small physical size, fast thermal response and small calibration shifts when exposed to magnetic fields or ionizing radiation. This paper presents a review of Cernox™ temperature sensors with regard to their physical, thermometric and operational properties and environmental effects.

Courts, S. Scott; Swinehart, Philip R.

2003-09-01

448

Determination of fluoride in water - A modified zirconium-alizarin method  

USGS Publications Warehouse

A convenient, rapid colorimetric procedure using the zirconium-alizarin indicator acidified with sulfuric acid for the determination of fluoride in water is described. Since this acid indicator is stable indefinitely, it is more useful than other zirconium-alizarin reagents previously reported. The use of sulfuric acid alone in acidifying the zirconium-alizarin reagent makes possible the maximum suppression of the interference of sulfate. Control of the pH of the samples eliminates errors due to the alkalinity of the samples. The fluoride content of waters containing less than 500 parts per million of sulfate and less than 1000 p.p.m. of chloride may be determined within a limit of 0.1 p.p.m. when a 100-ml. sample is used.

Lamar, W.L.

1945-01-01

449

Solid-phase zirconium and fluoride species in alkaline zircaloy cladding waste at Hanford.  

PubMed

The United States Department of Energy Hanford Site, near Richland, Washington, USA, processed plutonium between 1944 and 1987. Fifty-six million gallons of waste of various origins remain, including waste from removing zircaloy fuel cladding using the so-called Zirflex process. The speciation of zirconium and fluoride in this waste is important because of the corrosivity and reactivity of fluoride as well as the (potentially) high density of Zr-phases. This study evaluates the solid-phase speciation of zirconium and fluoride using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Two waste samples were analyzed: one waste sample that is relatively pure zirconium cladding waste from tank 241-AW-105 and another that is a blend of zirconium cladding wastes and other high-level wastes from tank 241-C-104. Villiaumite (NaF) was found to be the dominant fluoride species in the cladding waste and natrophosphate (Na7F[PO4]2 · 19H2O) was the dominant species in the blended waste. Most zirconium was present as a sub-micron amorphous Na-Zr-O phase in the cladding waste and a Na-Al-Zr-O phase in the blended waste. Some zirconium was present in both tanks as either rounded or elongated crystalline needles of Na-bearing ZrO2 that are up to 200 ?m in length. These results provide waste process planners the speciation data needed to develop disposal processes for this waste. PMID:24976128

Reynolds, Jacob G; Huber, Heinz J; Cooke, Gary A; Pestovich, John A

2014-08-15

450

Bayesian model selection validates a biokinetic model for zirconium processing in humans  

PubMed Central

Background In radiation protection, biokinetic models for zirconium processing are of crucial importance in dose estimation and further risk analysis for humans exposed to this radioactive substance. They provide limiting values of detrimental effects and build the basis for applications in internal dosimetry, the prediction for radioactive zirconium retention in various organs as well as retrospective dosimetry. Multi-compartmental models are the tool of choice for simulating the processing of zirconium. Although easily interpretable, determining the exact compartment structure and interaction mechanisms is generally daunting. In the context of observing the dynamics of multiple compartments, Bayesian methods provide efficient tools for model inference and selection. Results We are the first to apply a Markov chain Monte Carlo approach to compute Bayes factors for the evaluation of two competing models for zirconium processing in the human body after ingestion. Based on in vivo measurements of human plasma and urine levels we were able to show that a recently published model is superior to the standard model of the International Commission on Radiological Protection. The Bayes factors were estimated by means of the numerically stable thermodynamic integration in combination with a recently developed copula-based Metropolis-Hastings sampler. Conclusions In contrast to the standard model the novel model predicts lower accretion of zirconium in bones. This results in lower levels of noxious doses for exposed individuals. Moreover, the Bayesian approach allows for retrospective dose assessment, including credible intervals for the initially ingested zirconium, in a significantly more reliable fashion than previously possible. All methods presented here are readily applicable to many modeling tasks in systems biology. PMID:22863152

2012-01-01

451

Interaction of sorbed Ni(II) ions with amorphous zirconium hydrogen phosphate  

NASA Astrophysics Data System (ADS)

Samples of amorphous zirconium hydrogen phosphate with different zirconium and phosphorus concentrations in hydrogen and nickel-substituted forms are studied by means of electronic, 31P NMR, and impedance spectroscopy. It is shown that Ni(II) ? H+ ion exchange is accompanied by the hydrolysis of sorbed cations and the formation of complexes with the dihydro- and hydrophosphate groups of the inorganic ionite. It is found that the coordination environment of Ni(II) in the sorbent phase includes 2-4 fragments of phosphate groups, along with OH groups and water molecules.

Dzyazko, Yu. S.; Trachevskii, V. V.; Rozhdestvenskaya, L. M.; Vasilyuk, S. L.; Belyakov, V. N.

2013-05-01

452

Nuclear Magnetic Resonance Studies of Amorphous Nickel-Zirconium Hydrides.  

NASA Astrophysics Data System (ADS)

This research deals with one aspect of the scientific field of hydrogen in metals. The study of hydrogen in metals is technologically important for many reasons, among them is the use of hydrogen in metals to store energy. Hydrogen related energy technology is particularly attractive because hydrogen can be extracted from water, our most abundant resource, and can be used without any pollution. Metal hydrides may one day be widely used for automotive propulsion in cars, in batteries, and many other energy conversion devices. Amorphous NiZr is particularly interesting for hydrogen storage because high concentrations of hydrogen can be sorbed and desorbed repeatedly with only small deleterious effects to the metal. The motion of hydrogen and deuterium in amorphous nickel zirconium alloys (a-NiZr) has been studied and some properties of the local atomic structure in this amorphous metal have been deduced. This has been accomplished with nuclear magnetic resonance experiments measuring the spin lattice relaxation rate R_1 as a function of temperature and resonance frequency. Hydrogen can diffuse into and then through metals by hopping among interstitial positions. In a-NiZr the interstitial hydrogen positions are the centers of tetrahedra, with metal ions at the corners of the tetrahedra. Diffusive hydrogen motion occurs via classical over the barrier jumps, with a Gaussian distribution of activation energies for diffusion. The existence of a distribution of activation energies for diffusion is evidence supporting the densely packed random sphere model for the atomic structure of amorphous metals. The low temperature R_1 data is anomalous. Precipitation of Ni clusters out of the a-NiZr lattice may be occurring and causing unexpected spin lattice relaxation.

Hoke, Harris Clarence, Jr.

453

Ultrasonic texture characterization of aluminum, zirconium and titanium alloys  

SciTech Connect

This work attempts to show the feasibility of nondestructive characterization of non-ferrous alloys. Aluminum alloys have a small single crystal anisotropy which requires very precise ultrasonic velocity measurements for derivation of orientation distribution coefficients (ODCs); the precision in the ultrasonic velocity measurement required for aluminum alloys is much greater than is necessary for iron alloys or other alloys with a large single crystal anisotropy. To provide greater precision, some signal processing corrections need to be applied to account for the inherent, half-bandwidth offset in triggered pulses when using a zero-crossing technique for determining ultrasonic velocity. In addition, alloys with small single crystal anisotropy show a larger dependence on the single crystal elastic constants (SCECs) when predicting ODCs which require absolute velocity measurements. Attempts were made to independently determine these elastics constants in an effort to improve correlation between ultrasonically derived ODCs and diffraction derived ODCs. The greater precision required to accurately derive ODCs in aluminum alloys using ultrasonic nondestructive techniques is easily attainable. Ultrasonically derived ODCs show good correlation with derivations made by Bragg diffraction techniques, both neutron and X-ray. The best correlation was shown when relative velocity measurements could be used in the derivations of the ODCs. Calculation of ODCs in materials with hexagonal crystallites can also be done. Because of the crystallite symmetries, more information can be extracted using ultrasonic techniques, but at a cost of requiring more physical measurements. Some industries which use materials with hexagonal crystallites, e.g. zirconium alloys and titanium, have traditionally used texture parameters which provide some specialized measure of the texture. These texture parameters, called Kearns factors, can be directly related to ODCs.

Anderson, A.J.

1997-10-08

454

Thermal properties of zirconium diboride -- transition metal boride solid solutions  

NASA Astrophysics Data System (ADS)

This research focuses on the thermal properties of zirconium diboride (ZrB2) based ceramics. The overall goal was to improve the understanding of how different transition metal (TM) additives influence thermal transport in ZrB2. To achieve this, ZrB2 with 0.5 wt% carbon, and 3 mol% of individual transition metal borides, was densified by hot-press sintering. The transition metals that were investigated were: Y, Ti, Hf, V, Nb, Ta, Cr, Mo, W, and Re. The room temperature thermal diffusivities of the compositions ranged from 0.331 cm2/s for nominally pure ZrB2 to 0.105 cm2/s for (Zr,Cr)B2 and converged around 0.155cm2/s at higher temperatures for all compositions. Thermal conductivities were calculated from the diffusivities, using temperature-dependent values for density and heat capacity. The electron contribution to thermal conductivity was calculated from measured electrical resistivity according to the Wiedemann-Franz law. The phonon contribution to thermal conductivity was calculated by subtracting the electron contribution from the total thermal conductivity. Rietveld refinement of x-ray diffraction data was used to determine the lattice parameters of the compositions. The decrease in thermal conductivity for individual additives correlated directly to the metallic radius of the additive. Additional strain appeared to exist for additives when the stable TM boride for that metal had different crystal symmetries than ZrB2. This research provided insight into how additives and impurities affect thermal transport in ZrB2. The research potentially offers a basis for future modeling of thermal conductivity in ultra-high temperature ceramics based on the correlation between metallic radius and the decrease in thermal conductivity.

McClane, Devon Lee

455

Occurrence and stability of trivalent zirconium in orthophosphate single crystals  

SciTech Connect

EPR spectroscopy has been used in investigations of the unusual 3+ valence state of zirconium. The EPR spectrum of Zr/sup 3 +/, which was initially observed as a parasitic signal in Fe-doped single crystals of ScPO/sub 4/, was definitively identified by preparing single crystals of ScPO/sub 4/ doped with isotopically enriched (94.6%)/sup 91/Zr. Single crystals of LuPO/sub 4/ and YPO/sub 4/ doped with both naturally abundant and isotopically enriched Zr were also grown and investigated. The EPR spectrum of Zr/sup 3 +/ could be observed at room temperature in the ''as-grown'' single crystals of both ScPO/sub 4/ and LuPO/sub 4/; and, accordingly, the 3+ state is stable at room temperature in these hosts. The spectrum of Zr/sup 3 +/ in the YPO/sub 4/ host could only be observed following a ..gamma.. irradiation at 77 K, and this spectrum decayed rapidly with increasing temperature. Axial spin-Hamiltonian parameters were determined for Zr/sup 3 +/ in all three hosts at a sample temperature of 77 K and at room temperature for the ScPO/sub 4/ and LuPO/sub 4/ hosts. In the case of the latter two hosts, the spin-Hamiltonian parameters were found to exhibit a small temperature dependence. The observed g values were not accounted for by previously published second-order expressions indicating that additional coupling mechanisms are operative.

Abraham, M.M.; Boatner, L.A.; Ramey, J.O.; Rappaz, M.

1984-12-15

456

Full-mouth oral rehabilitation in a titanium allergy patient using zirconium oxide dental implants and zirconium oxide restorations. A case report from an ongoing clinical study.  

PubMed

This case report describes the full-mouth oral rehabilitation of a titanium allergic patient. The patient was a young female with amelogenesis imperfecta who had generalized massive tooth destruction. All teeth in the mouth were extracted and 15 CeraRoot acid-etched (ICE surface) implants were placed (seven implants in the maxilla and eight implants in the mandible). No immediate temporaries were placed. Temporaries were placed 3 months after surgery, and left in function for 2 months. The case was finally restored with zirconium oxide bridges and ceramic veneering (three bridges in the maxilla and another three in the mandible). The 3-year follow-up showed good stability of soft tissues and bone level. Zirconium oxide implants and restorations might be an alternative for the oral rehabilitation of titanium allergic patients. PMID:20589262

Oliva, Xavi; Oliva, Josep; Oliva, Josep D

2010-01-01

457

47 CFR 97.215 - Telecommand of model craft.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.215 Telecommand of model craft. An amateur station transmitting signals to control a model...

2010-10-01

458

47 CFR 97.221 - Automatically controlled digital station.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.221 Automatically controlled digital station. (a) This rule section does not apply to an...

2011-10-01

459

47 CFR 97.211 - Space telecommand station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.211 Space telecommand station. (a) Any amateur station designated by the licensee of a...

2013-10-01

460

47 CFR 97.211 - Space telecommand station.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.211 Space telecommand station. (a) Any amateur station designated by the licensee of a...

2011-10-01

461

47 CFR 97.221 - Automatically controlled digital station.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.221 Automatically controlled digital station. (a) This rule section does not apply to an...

2010-10-01

462

47 CFR 97.211 - Space telecommand station.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.211 Space telecommand station. (a) Any amateur station designated by the licensee of a...

2012-10-01

463

47 CFR 97.219 - Message forwarding system.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station may participate in a message...

2013-10-01

464

47 CFR 97.215 - Telecommand of model craft.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.215 Telecommand of model craft. An amateur station transmitting signals to control a model...

2011-10-01

465

47 CFR 97.215 - Telecommand of model craft.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.215 Telecommand of model craft. An amateur station transmitting signals to control a model...

2013-10-01

466

47 CFR 97.219 - Message forwarding system.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station may participate in a message...

2012-10-01

467

47 CFR 97.213 - Telecommand of an amateur station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.213 Telecommand of an amateur station. An amateur station on or within 50 km of the Earth's...

2013-10-01

468

47 CFR 97.219 - Message forwarding system.  

Code of Federal Regulations, 2010 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station may participate in a message...

2010-10-01

469

47 CFR 97.219 - Message forwarding system.  

Code of Federal Regulations, 2011 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.219 Message forwarding system. (a) Any amateur station may participate in a message...

2011-10-01

470

47 CFR 97.221 - Automatically controlled digital station.  

Code of Federal Regulations, 2013 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.221 Automatically controlled digital station. (a) This rule section does not apply to an...

2013-10-01

471

47 CFR 97.221 - Automatically controlled digital station.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.221 Automatically controlled digital station. (a) This rule section does not apply to an...

2012-10-01

472

47 CFR 97.215 - Telecommand of model craft.  

Code of Federal Regulations, 2012 CFR

... FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Special Operations § 97.215 Telecommand of model craft. An amateur station transmitting signals to control a model...

2012-10-01

473

19 CFR 12.97 - Importations contrary to law.  

Code of Federal Regulations, 2010 CFR

...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

2010-04-01

474

19 CFR 12.97 - Importations contrary to law.  

Code of Federal Regulations, 2012 CFR

...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

2012-04-01

475

19 CFR 12.97 - Importations contrary to law.  

...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

2014-04-01

476

19 CFR 12.97 - Importations contrary to law.  

Code of Federal Regulations, 2013 CFR

...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

2013-04-01

477

19 CFR 12.97 - Importations contrary to law.  

Code of Federal Regulations, 2011 CFR

...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

2011-04-01

478

14 CFR 151.97 - Maintenance and repair.  

Code of Federal Regulations, 2011 CFR

...FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRPORTS FEDERAL AID TO AIRPORTS Project Programming Standards § 151.97 Maintenance and repair. (a) Maintenance work is not airport development as...

2011-01-01

479

47 CFR 97.29 - Replacement license grant document.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.29 Replacement license grant document. Each grantee whose amateur station license grant document is lost, mutilated or...

2011-10-01

480

47 CFR 97.29 - Replacement license grant document.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.29 Replacement license grant document. Each grantee whose amateur station license grant document is lost, mutilated or...

2012-10-01

481

47 CFR 97.527 - Reimbursement for expenses.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.527...processing, administering, or coordinating an examination for an amateur operator license. [66 FR 20752, Apr. 25,...

2012-10-01

482

47 CFR 97.305 - Authorized emission types.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Technical Standards § 97.305 Authorized...types. (a) Except as specified elsewhere in this part, an amateur station may transmit a CW emission on any frequency...

2012-10-01

483

47 CFR 97.527 - Reimbursement for expenses.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.527...processing, administering, or coordinating an examination for an amateur operator license. [66 FR 20752, Apr. 25,...

2013-10-01

484

47 CFR 97.29 - Replacement license grant document.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.29 Replacement license grant document. Each grantee whose amateur station license grant document is lost, mutilated or...

2013-10-01

485

47 CFR 97.29 - Replacement license grant document.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE General Provisions § 97.29 Replacement license grant document. Each grantee whose amateur station license grant document is lost, mutilated or...

2010-10-01

486

47 CFR 97.405 - Station in distress.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97... (a) No provision of these rules prevents the use by an amateur station in distress of any means at its disposal to...

2012-10-01

487

47 CFR 97.103 - Station licensee responsibilities.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.103 ...with the FCC Rules. When the control operator is a different amateur operator than the station licensee, both persons are...

2011-10-01

488

47 CFR 97.103 - Station licensee responsibilities.  

Code of Federal Regulations, 2012 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.103 ...with the FCC Rules. When the control operator is a different amateur operator than the station licensee, both persons are...

2012-10-01

489

47 CFR 97.405 - Station in distress.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97... (a) No provision of these rules prevents the use by an amateur station in distress of any means at its disposal to...

2010-10-01

490

47 CFR 97.527 - Reimbursement for expenses.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.527...processing, administering, or coordinating an examination for an amateur operator license. [66 FR 20752, Apr. 25,...

2011-10-01

491

47 CFR 97.103 - Station licensee responsibilities.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.103 ...with the FCC Rules. When the control operator is a different amateur operator than the station licensee, both persons are...

2013-10-01

492

47 CFR 97.405 - Station in distress.  

Code of Federal Regulations, 2011 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97... (a) No provision of these rules prevents the use by an amateur station in distress of any means at its disposal to...

2011-10-01

493

47 CFR 97.405 - Station in distress.  

Code of Federal Regulations, 2013 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications § 97... (a) No provision of these rules prevents the use by an amateur station in distress of any means at its disposal to...

2013-10-01

494

47 CFR 97.305 - Authorized emission types.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Technical Standards § 97.305 Authorized...types. (a) Except as specified elsewhere in this part, an amateur station may transmit a CW emission on any frequency...

2010-10-01

495

47 CFR 97.527 - Reimbursement for expenses.  

Code of Federal Regulations, 2010 CFR

...COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Qualifying Examination Systems § 97.527...processing, administering, or coordinating an examination for an amateur operator license. [66 FR 20752, Apr. 25,...

2010-10-01

496

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2010-10-01

497

46 CFR 98.25-97 - Nondestructive testing.  

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2014-10-01

498

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2012 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2012-10-01

499

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2011 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2011-10-01

500

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2013 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2013-10-01