Sample records for black powder substitutes

  1. The analysis of black powder substitutes containing ascorbic acid by ion chromatography/mass spectrometry.

    PubMed

    Lang, Gui-hua Lisa; Boyle, Katherine M

    2009-11-01

    Black powder substitutes containing ascorbic acid are a group of low explosives that utilize ascorbic acid as the fuel. The analysis of these powders is complicated by the degradation of ascorbic acid which occurs rapidly in solution and may also occur as the powder ages. Aqueous extracts of both intact powders and postblast residues were analyzed by an existing ion chromatography/mass spectrometry (IC/MS) method used at the Bureau of Alcohol, Tobacco, Firearms and Explosives. Results have shown that while ascorbic acid itself is not detected in this method, its diagnostic degradation products (threonic acid, monohydrated diketogulonic acid, and oxalic acid) can be identified. In addition, anions from the inorganic oxidizers (perchlorate and nitrate) and combustion products such as chloride, chlorate, and nitrite, can be identified within the same experiment. While this IC/MS method shows promise, future modifications are necessary because of limitations in identifying threonate in postblast residues, as well as coeluting compounds observed in postblast residues. PMID:19732276

  2. Coal as a Substitute for Carbon Black

    NASA Technical Reports Server (NTRS)

    Kushida, R. O.

    1982-01-01

    New proposal shows sprayed coal powder formed by extrusion of coal heated to plastic state may be inexpensive substitute for carbon black. Carbon black is used extensively in rubber industry as reinforcing agent in such articles as tires and hoses. It is made from natural gas and petroleum, both of which are in short supply.

  3. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  4. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  5. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  6. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  7. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  8. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  9. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  10. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  11. 30 CFR 57.6901 - Black powder.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  12. 30 CFR 56.6901 - Black powder.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...6901 Black powder. (a) Black powder shall be used for...stone. (b) Containers of black powder shall be (1) Nonsparking...of this section. (c) Black powder shall be transferred...damaged explosives. (f) Holes shall not be reloaded for...

  13. Substitution of Micron by Nanometer Scale Powders in Magnetorheological Fluids

    NASA Astrophysics Data System (ADS)

    Chaudhuri, A.; Wang, G.; Wereley, N. M.; Tasovksi, Vasil; Radhakrishnan, R.

    The effects of substitution of micron size powder by nanometer size powder in magnetorheological (MR) fluids are investigated in this study. Three MR fluid samples containing iron powder with 45% weight fraction in a carrier fluid were made by Materials Modification Inc. The difference among these three fluids is size of the magnetic particles. The first MR fluid sample contained only micron size iron powder with 10?m particle size. In the second sample, 5% micron iron was substituted with nano powders having 30~40nm mean diameter, while the third sample had 37.5% micron powder and 7.5% nano powder. Rheological tests were conducted on the three samples using a parallel disk rheometer. Highest yield stress was observed in the second MR fluid sample containing 40% micron and 5% nano iron powder. By replacing only 5% micron iron powder with nanoparticles, we achieved substantial increment in yield stress. However, when nano powder content is increased to 7.5%, the yield stress decreases and is lower than that in the all micron MR fluid. Thus, by doping a reasonable percent of nano iron powder in the MR fluid, a substantial change in the rheological characteristics is obtainable. Further investigations of effects of nano iron powder in MR fluids for higher weight fraction MR fluids will be carried out in future.

  14. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  15. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  16. 49 CFR 173.170 - Black powder for small arms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Black powder for small arms. 173.170 Section 173.170 Transportation...and Class 7 173.170 Black powder for small arms. Black powder for small arms that has been classed in Division 1.1 may...

  17. Here are procedures for handling persistent black-powder contamination

    Microsoft Academic Search

    1998-01-01

    Recent research into black powder problems experienced by natural-gas transmission pipelines indicates steps that can be taken to control the material in gas pipelines, gathering systems, and storage facilities. Black powder (the common term for various forms of iron sulfide mixed with contaminants) is the least understood but most prominent contaminant in natural-gas pipelines and compression equipment in pipeline, refinery,

  18. 2. LOOKING SOUTH TOWARD BUILDING NO. 602, BLACK POWDER BLENDER. ...

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

    2. LOOKING SOUTH TOWARD BUILDING NO. 602, BLACK POWDER BLENDER. ALL LIGHTING IS ON EXTERIOR OF BUILDING TO MINIMIZE EXPLOSION HAZARD. ALL METAL CONDUIT AND PIPING IS GROUNDED. - Picatinny Arsenal, 600 Area, Test Areas District, State Route 15 near I-80, Dover, Morris County, NJ

  19. NdCo substituted strontium hexaferrite powders with enhanced coercivity

    SciTech Connect

    Herme, C.A. [Facultad de Ingeniera, Universidad de Buenos Aires, LAFMACEL-INTECIN, Paseo Coln 850, 1063 Buenos Aires (Argentina)] [Facultad de Ingeniera, Universidad de Buenos Aires, LAFMACEL-INTECIN, Paseo Coln 850, 1063 Buenos Aires (Argentina); Bercoff, P.G., E-mail: bercoff@famaf.unc.edu.ar [Facultad de Matemtica, Astronoma y Fsica, Universidad Nacional de Crdoba, IFEG, CONICET, Ciudad Universitaria, 5000 Crdoba (Argentina); Jacobo, S.E. [Facultad de Ingeniera, Universidad de Buenos Aires, LAFMACEL-INTECIN, Paseo Coln 850, 1063 Buenos Aires (Argentina)] [Facultad de Ingeniera, Universidad de Buenos Aires, LAFMACEL-INTECIN, Paseo Coln 850, 1063 Buenos Aires (Argentina)

    2012-11-15

    Graphical abstract: Display Omitted Highlights: ? Sr{sub 1?x}Nd{sub x}Fe{sub 11?x}Co{sub x}O{sub 19} was prepared by solgel auto-combustion method with 0 ? x ? 0.4. ? Coercivity increases 11% with 0.2 NdCo substitution, reaching a value of 68.9 A/m. ? The appearance of two magnetic orderings is noticed in susceptibility measurements. ? This is supported by Curie temperature and susceptibility data. -- Abstract: In this work we report the synthesis of NdCo substituted strontium hexaferrites of composition Sr{sub 1?x}Nd{sub x}Fe{sub 11?x}Co{sub x}O{sub 19} by the solgel auto-combustion method with further heat treatment. The analysis of the X-ray diffraction spectra shows the M-type hexagonal structure in samples treated at 1100 C for 2 h. Coercivity increases 11% with 0.2 NdCo substitution, reaching a value of 68.9 A/m (5480 Oe) while saturation magnetization is reduced 6% to 91 A m{sup 2}/kg (91 emu/g). The behavior of magnetic susceptibility with an applied field shows two different maxima which are assigned to different magnetic orderings. This assumption is supported by the appearance of two experimental values of Curie temperatures (T{sub C}) for all the prepared samples. Magnetic susceptibility ? and T{sub C} measurements suggest an uneven distribution of the iron vacancies.

  20. Spherical Granule Production from Micronized Saltwort (Salicornia herbacea) Powder as Salt Substitute

    PubMed Central

    Shin, Myung-Gon; Lee, Gyu-Hee

    2013-01-01

    The whole saltwort plant (Salicornia herbacea) was micronized to develop the table salt substitute. The micronized powder was mixed with distilled water and made into a spherical granule by using the fluid-bed coater (SGMPDW). The SGMPDW had superior flowability to powder; however, it had low dispersibility. To increase the dispersibility of SGMPDW, the micronized powder was mixed with the solution, which contained various soluble solid contents of saltwort aqueous extract (SAE), and made into a spherical granule (SGMPSAE). The SGMPSAE prepared with the higher percentages of solid content of SAE showed improved dispersibility in water and an increase in salty taste. The SGMPSAE prepared with 10% SAE was shown to possess the best physicochemical properties and its relative saltiness compared to NaCl (0.39). In conclusion, SGMPSAEs can be used as a table salt substitute and a functional food material with enhanced absorptivity and convenience. PMID:24471111

  1. Spherical Granule Production from Micronized Saltwort (Salicornia herbacea) Powder as Salt Substitute.

    PubMed

    Shin, Myung-Gon; Lee, Gyu-Hee

    2013-03-01

    The whole saltwort plant (Salicornia herbacea) was micronized to develop the table salt substitute. The micronized powder was mixed with distilled water and made into a spherical granule by using the fluid-bed coater (SGMPDW). The SGMPDW had superior flowability to powder; however, it had low dispersibility. To increase the dispersibility of SGMPDW, the micronized powder was mixed with the solution, which contained various soluble solid contents of saltwort aqueous extract (SAE), and made into a spherical granule (SGMPSAE). The SGMPSAE prepared with the higher percentages of solid content of SAE showed improved dispersibility in water and an increase in salty taste. The SGMPSAE prepared with 10% SAE was shown to possess the best physicochemical properties and its relative saltiness compared to NaCl (0.39). In conclusion, SGMPSAEs can be used as a table salt substitute and a functional food material with enhanced absorptivity and convenience. PMID:24471111

  2. Polyolefin backbone substitution in binders for low temperature powder injection moulding feedstocks.

    PubMed

    Hausnerova, Berenika; Kuritka, Ivo; Bleyan, Davit

    2014-01-01

    This paper reports the substitution of polyolefin backbone binder components with low melting temperature carnauba wax for powder injection moulding applications. The effect of various binder compositions of Al?O? feedstock on thermal degradation parameters is investigated by thermogravimetric analysis. Within the experimental framework 29 original feedstock compositions were prepared and the superiority of carnauba wax over the polyethylene binder backbone was demonstrated in compositions containing polyethylene glycol as the initial opening agent and governing the proper mechanism of the degradation process. Moreover, the replacement of synthetic polymer by the natural wax contributes to an increase of environmental sustainability of modern industrial technologies. PMID:24583880

  3. Sensitive detection of black powder by stand-alone ion mobility spectrometer with chlorinated hydrocarbon modifiers in drift gas.

    PubMed

    Liang, Xixi; Wang, Xin; Wang, Weiguo; Zhou, Qinghua; Chen, Chuang; Peng, Liying; Wen, Meng; Qu, Tuanshuai; Wang, Zhenxin; Zhao, Kun; Li, Jinghua; Li, Haiyang

    2014-04-01

    This paper introduces a simple method for selective and sensitive detection of black powder by adding chlorinated hydrocarbons in the drift gas instead of changing the structure of conventional ion mobility spectrometer (IMS). The function of chloride modifiers was to substitute Cl(-)(H?O)n for [O?? (H?O)(n)] in the drift region so as to avoid the overlap between O?? (H?O)(n) and sulfur ion peaks. Among CH?Cl?, CHCl? and CCl?, CCl? was chosen as the modifier due to the best peak-to-peak resolution and stability towards the fluctuation of modifier concentration. With 1.4 ppm CCl? as the modifier, the minimum detectable quantity of 0.1 ng for sulfur was achieved. Moreover, this method showed the ability for detection of common explosives at sub-nanogram level, such as black powder (BP), ammonium nitrate fuel oil (ANFO), 2,4,6-trinitrotoluene (TNT), and pentaerythritol tetranitrate (PETN). In summary, this method requiring no configuration modification has high sensitivity and selectivity, and consumes trace amount of modifier. And these characteristics make it easy to be adopted in current deployed IMS to detect black powder explosives. PMID:24607130

  4. Influence of Mg-substitution on the physicochemical properties of calcium phosphate powders

    SciTech Connect

    Marchi, J. [University of Erlangen-Nuernberg, Department of Materials Science-Biomaterials, Henkestr. 91, D-91052 Erlangen (Germany); Institute of Energetic and Nuclear Research (IPEN), Centre of Science and Materials Technology, Department of Ceramics, Av. Prof. Lineu Prestes, 2242, 05508-000 Sao Paulo, SP (Brazil); Dantas, A.C.S. [University of Erlangen-Nuernberg, Department of Materials Science-Biomaterials, Henkestr. 91, D-91052 Erlangen (Germany); Greil, P. [University of Erlangen-Nuernberg, Department of Materials Science-Biomaterials, Henkestr. 91, D-91052 Erlangen (Germany); Bressiani, J.C. [Institute of Energetic and Nuclear Research (IPEN), Centre of Science and Materials Technology, Department of Ceramics, Av. Prof. Lineu Prestes, 2242, 05508-000 Sao Paulo, SP (Brazil); Bressiani, A.H.A. [Institute of Energetic and Nuclear Research (IPEN), Centre of Science and Materials Technology, Department of Ceramics, Av. Prof. Lineu Prestes, 2242, 05508-000 Sao Paulo, SP (Brazil); Mueller, F.A. [University of Erlangen-Nuernberg, Department of Materials Science-Biomaterials, Henkestr. 91, D-91052 Erlangen (Germany)]. E-mail: Frank.Mueller@ww.uni-erlangen.de

    2007-06-05

    Tricalcium phosphate based ceramics (TCP) are bioresorbable and thereby considered to be promising bone replacement materials. The differences in crystal structure between {alpha} and {beta}-TCP phases gives rise for different dissolution rates in vitro and in vivo, which may alter the bioresorbable behavior of TCP ceramics. It is suggested that the addition of magnesium ions, which are also present in biological tissues, stabilizes {beta}-phase to higher temperatures and thus enables the sintering of {beta}-TCP at elevated temperatures compared to Mg free TCP. In this paper, Mg-substituted TCP, with the general formula (Ca{sub 1-x}Mg {sub x}){sub 3}(PO{sub 4}){sub 2} and 0.01 {<=} x {<=} 0.045, were produced by wet chemical synthesis from Ca(OH){sub 2}, H{sub 3}PO{sub 4} and MgO, after calcinations at three different temperatures between 750 and 1050 deg. C. The influence of different amounts of Mg substitution on the physical properties, microstructure, and sintering behavior of calcium phosphate powders was evaluated. Thermal analytical techniques, together with X-ray diffraction analysis, were successfully combined in order to characterize the occurring phase transformations during annealing of the powders. The results show that the addition of small amounts of Mg (up to 1.5 mol%) are adequate to postpone the {beta}-{alpha} TCP phase transformation to 1330 deg. C and to accelerate the densification process during sintering of {beta}-TCP ceramics.

  5. Influence of the partial substitution of skim milk powder for soy extract on ice cream structure and quality

    Microsoft Academic Search

    Gustavo das Graas Pereira; Jaime Vilela de Resende; Luiz Ronaldo de Abreu; Tales Mrcio de Oliveira Giarola; Italo Tuler Perrone

    2011-01-01

    In the present work, we aimed to study the influence of the partial substitution of skim milk powder for soy extract (SE)\\u000a on the quality characteristics of ice cream. Physical and chemical composition, rheologic behavior, overrun value, hardness,\\u000a melting characteristics, and sensory properties were evaluated at levels of 0, 10, 20, and 30% substitution. The size and\\u000a distribution of the

  6. Solid state NMR study of dietary fiber powders from aronia, bilberry, black currant and apple

    Microsoft Academic Search

    I. Wawer; M. Wolniak; K. Paradowska

    2006-01-01

    13C CPMAS NMR spectra of dietary fiber powders from aronia (chokeberry), bilberry, black currant and apple were recorded. The spectra are complex owing to superposition of resonances from different polysaccharides and polyphenolic compounds. Standard, dipolar dephased and the T1?H partially relaxed spectra enabled the identification of several constituents: microcrystalline cellulose, pectins, lignins, cutin-like polymers and condensed tannins. The fiber powders

  7. The substitution of nickel for cobalt in hot isostatically pressed powder metallurgy UDIMET 700 alloys

    NASA Technical Reports Server (NTRS)

    Harf, F. H.

    1985-01-01

    Nickel was substituted in various proportions for cobalt in a series of five hot-isostatically-pressed powder metallurgy alloys based on the UDIMET 700 composition. These alloys were given 5-step heat treatments appropriate for use in turbine engine disks. The resultant microstructures displayed three distinct sizes of gamma-prime particles in a gamma matrix. The higher cobalt-content alloys contained larger amounts of the finest gamma-prime particles, and had the lowest gamma-gamma-prime lattice mismatch. While all alloys had approximately the same tensile properties at 25 and 650 gamma C, the rupture lives at 650 and 760 C peaked in the alloys with cobalt contents between 12.7 and 4.3 pct. Minimum creep rates increased as cobalt contents were lowered, suggesting their correlation with the gamma-prime particle size distribution and the gamma-gamma-prime mismatch. It was also found that, on overaging at temperatures higher than suitable for turbine disk use, the high cobalt-content alloys were prone to sigma phase formation.

  8. Lifting techniques for finger marks on human skin previous enhancement by Swedish Black powder A preliminary study

    Microsoft Academic Search

    Matej Trapecar

    2009-01-01

    An examination was done to investigate whether certain lifting techniques can lift recovered latent fingerprints on human skin surfaces of living subjects. For recovery Swedish Soot powder mixture (Swedish Black) was used.Donors intentionally placed fingerprints on the skin surface of living subjects. Finger marks were then in all cases recovered with Swedish Black powder. The procedure was repeated after 1h

  9. Structural and optical absorption studies of barium substituted strontium ferrite powder

    NASA Astrophysics Data System (ADS)

    Jaiswal, Shivendra Kumar; Kumar, Jitendra

    2012-08-01

    Attempt has been made to synthesize BaxSr1-xFeO3-? (x = 0-1.0) ferrite powder by decomposition of sol-gel derived oxalate at 800-1000 C for 5-10 h to study the effect of barium insertion with regard to phase(s), stability, optical behavior, oxidation states of iron, and oxygen deficiency. It is shown that these ferrites possess a perovskite-type cubic phase (a = 3.877-4.020, Z = 1, space group Pm3m) for 0.1 ? x ? 0.94, a mixture of 82% rhombohedral (aR = 5.666 and ?R = 59.761, Z = 2, space group R3c) and 18% hexagonal phases for x = 0.96 and a pure hexagonal (a = 5.689, c = 13.944, Z = 6, space group P63/mmc) phase for x = 1. Barium substitution in SrFeO3-? system leads to lattice expansion, weakening of the metal-oxygen bond, reduction of tetravalent iron ions (as evident from Mossbauer analysis), and decrease of oxygen content. The optical absorption peaks observed in the range 3.17-4.11 eV are attributed to charge transfer transitions from O2- (2p) to Fe (3d) band. The values of optical energy band gap of BaxSr1-xFeO3-? are found to be 5.48 and 4.04 for x = 0.1 and 1.0, respectively. A stable perovskite-type cubic phase in BaxSr1-xFeO3-? system with significant anion deficiency (? = 0.26-0.32) may possibly act as an oxygen permeable membrane.

  10. Evaluating Renewable Cornstarch/biochar Fillers as Potential Substitutes for Carbon Black in SBR Composites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The continually growing demand for fossil fuels coupled with the potential risk of relying on foreign sources for these fuels strengthens the need to find renewable substitutes for petroleum products. Carbon black is a petroleum product that dominates the rubber composite filler market. Agricultur...

  11. Magnetic exchange interactions of rare-earth-substituted DyCrO3 bulk powders

    NASA Astrophysics Data System (ADS)

    McDannald, A.; Kuna, L.; Seehra, M. S.; Jain, M.

    2015-06-01

    Effects of the substitution of rare-earths R =Y , Er, and Ho on the magnetic properties of Dy0.7R0.3CrO3 are reported here in order to probe the nature of magnetism and related exchange interactions in these materials. By fitting the temperature dependence of the magnetic susceptibility to a modified Curie-Weiss law, which includes a correction for the Dzyaloshinskii-Moriya (DM) interaction, the strengths of the symmetric and antisymmetric Cr3 +-Cr3 + exchange interactions were determined. It was found that the rare-earth substitutions had a slight effect on the strength of the symmetric Cr3 +-Cr3 + interaction (reflected in the slight changes in the Nel temperatures), while the antisymmetric Cr3 +-Cr3 + interaction remained unchanged. Isothermal magnetic measurements of the samples at successive temperatures revealed a plateau in the temperature dependent magnetic coercivity data, which was explained by the magnetic properties of the substituted ions. It was found that the Y substitution led to the reduction of the strength of the magnetization and a larger peak value of magnetic coercivity as compared to that in pure DyCrO3. The observed increase in magnetic coercivity with Er and Ho substitution can be attributed to an increased R3 +-Cr3 + interaction strength dominated by the DM mechanism.

  12. Sol-Gel Preparation and Properties of Fluoride-Substituted Hydroxyapatite Powders

    Microsoft Academic Search

    Hae-Won Kim; Long-Hao Li; Young-Hag Koh; Jonathan C. Knowles; Hyoun-Ee Kim

    2004-01-01

    Hydroxyapatite (HA) and fluor-hydroxyapatite (FHA) pow- ders were synthesized by a sol-gel method for usage as bone filler and drug carrier. Calcium nitrate and triethyl phosphite were used as precursors under an ethanol-water-based solu- tion. Different amounts of ammonium fluoride (NH4F) were incorporated for the preparation of FHA powders. With heat treatment above 400C, a characteristic apatite phase was observed

  13. Production of strontium-substituted lanthanum manganite perovskite powder by the amorphous citrate process

    Microsoft Academic Search

    M. S. G. Baythoun; F. R. Sale

    1982-01-01

    The amorphous citrate process has been used to produce Mn2O3, Mn3O4, LaMnO3, SrMnO3 and strontium-substituted LaMnO3. The citrate-nitrate gels were dehydrated at 70 C to yield solid precursor materials. The decomposition\\/oxidation of the precursors have been studied using thermogravimetry and evolved gas analysis. The products of decomposition have been characterized by X-ray diffraction analysis, scanning electron microscopy and, in the

  14. Lifting techniques for finger marks on human skin previous enhancement by Swedish Black powder--a preliminary study.

    PubMed

    Trapecar, Matej

    2009-12-01

    An examination was done to investigate whether certain lifting techniques can lift recovered latent fingerprints on human skin surfaces of living subjects. For recovery Swedish Soot powder mixture (Swedish Black) was used. Donors intentionally placed fingerprints on the skin surface of living subjects. Finger marks were then in all cases recovered with Swedish Black powder. The procedure was repeated after 1 h and 4 h. Treated finger marks were secured and preserved as latent fingerprint evidence by different lifting processes. Having examined skin surfaces and finger marks we observed that the lifters such as white instant lifter, white fingerprint gelatin, black fingerprint gelatin, silicone, transparent adhesive tape, are suitable. Moreover, white fingerprint gelatin and white instant lifter proved to be very good at lifting treated finger marks. Black fingerprint gelatin was very good also, but finger marks were examined by slant light. PMID:20120609

  15. Effect of Nd substitution on structure and magnetic properties of Nd x Dy 3? x Fe 5 O 12 garnet powders

    Microsoft Academic Search

    Liming Yu; Jiujing Wang; Shixun Cao; Shujuan Yuan; Jincang Zhang

    2007-01-01

    The properties of light rare earth Nd substitution for heavy rare earth Dy in Dy3Fe5O12 (DyIG) garnet ferrite have been studied. The Nd\\u000a x\\u000a Dy3x\\u000a Fe5O12 (x=0, 0.25, 0.5, 0.75 and 1) (Nd:DyIG) garnet powders were prepared by solgel autocombustion followed by heat treatment.\\u000a The structure and the magnetic properties of the annealed powders were measured with X-ray diffraction (XRD),

  16. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (PMN...

  17. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (PMN...

  18. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (PMN...

  19. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (PMN...

  20. 40 CFR 721.10080 - Carbon black, 4-[(17-substituted-3,6,9,12,15-pentaazaheptadec-1-yl) substituted] phenyl-modified...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (generic...15-pentaazaheptadec-1-yl) substituted] phenyl-modified, hydrochlorides (PMN...

  1. Synthesis of Al4SiC4 powders from kaolin grog, aluminum and carbon black by carbothermal reaction

    NASA Astrophysics Data System (ADS)

    Yuan, Wenjie; Yu, Chao; Deng, Chengji; Zhu, Hongxi

    2013-12-01

    In this paper, the synthesis of Al4SiC4 used as natural oxide materials by carbothermal reduction was investigated in order to explore the synthesis route with low costs. The samples were calcined by using kaolin grog, aluminum and carbon black as raw materials with the selected proportion at the temperature from 1500 to 1800 C for 2 hours under flow argon atmosphere. The phase composition of reaction products were determined by X-ray diffraction. The microstructure and elemental composition of different phases were observed and identified by scanning electron microscopy and energy dispersive spectroscopy. The mechanism of reaction processing was discussed. The results show that Al4SiC4 powders composed of hexagonal plate-like particulates with various sizes and the thickness of less than 20 ?m are obtained when the temperature reaches 1800 C.

  2. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...substituted] phenyl- modified, sodium salts (generic). 721.10075 Section 721...substituted] phenyl- modified, sodium salts (generic). (a) Chemical substance...substituted] phenyl-modified, sodium salts (PMN P-05-722) is subject to...

  3. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...substituted] phenyl- modified, sodium salts (generic). 721.10075 Section 721...substituted] phenyl- modified, sodium salts (generic). (a) Chemical substance...substituted] phenyl-modified, sodium salts (PMN P-05-722) is subject to...

  4. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic...2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic...2-(Sulfooxy) ethyl]substituted] phenyl-modified, sodium salts (PMN...

  5. 40 CFR 721.10075 - Carbon black, 4-[[2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic...2-(Sulfooxy) ethyl]substituted] phenyl- modified, sodium salts (generic...2-(Sulfooxy) ethyl]substituted] phenyl-modified, sodium salts (PMN...

  6. Urinary excretion of phenolic acids in rats fed cranberry, blueberry, or black raspberry powder.

    PubMed

    Khanal, Ramesh; Howard, Luke R; Prior, Ronald L

    2014-05-01

    Dietary polyphenolics can be converted into smaller phenolic acids (PA) by microorganisms in the colon and may contribute to health benefits associated with the parent polyphenolics. Urinary excretion of 18 PA and their conjugates was studied, using HPLC-MS/MS, in rats fed AIN93G-based diets containing 5% (dry weight basis) of either cranberry (CB), blueberry (BB), or black raspberry (BRB). Hippuric, 4-hydroxyphenylacetic, 3-methoxy-4-hydroxyphenylacetic, and 4-hydroxybenzoic acids were excreted in greatest quantity in the urine over a 24 h period in all diets. Primary PA excreted in the berry diets were 4-hydroxycinnamic acid for CB; chlorogenic, ferulic, and 3,4-dihydroxycinnamic acids for BB; and 3-hydroxyphenylpropionic, 3-hydroxybenzoic, and 3-hydroxycinnamic acids for BRB. PA were present in conjugated form with cinnamic acid derivatives being 50-70% and phenylacetic acid derivatives conjugated <10%. Conjugated, and not just the free, PA are significant contributors to total urinary excretion. PMID:24180593

  7. Anti-inflammatory effects of freeze-dried black raspberry powder in ulcerative colitis.

    PubMed

    Montrose, David C; Horelik, Nicole A; Madigan, James P; Stoner, Gary D; Wang, Li-Shu; Bruno, Richard S; Park, Hea Jin; Giardina, Charles; Rosenberg, Daniel W

    2011-03-01

    Ulcerative colitis (UC) is a chronic inflammatory disease of the colonic mucosa that can dramatically increase the risk of colon cancers. In the present study, we evaluated the effects of a dietary intervention of freeze-dried black raspberries (BRB), a natural food product with antioxidant and anti-inflammatory bioactivities, on disease severity in an experimental mouse model of UC using 3% dextran sodium sulfate (DSS). C57BL/6J mice were fed either a control diet or a diet containing BRB (5 or 10%) for 7-14 days and then the extent of colonic injury was assessed. Dietary BRB markedly reduced DSS-induced acute injury to the colonic epithelium. This protection included better maintenance of body mass and reductions in colonic shortening and ulceration. BRB treatment, however, did not affect the levels of either plasma nitric oxide or colon malondialdehyde, biomarkers of oxidative stress that are otherwise increased by DSS-induced colonic injury. BRB treatment for up to 7 days suppressed tissue levels of several key pro-inflammatory cytokines, including tumor necrosis factor ? and interleukin 1?. Further examination of the inflammatory response by western blot analysis revealed that 7 day BRB treatment reduced the levels of phospho-I?B? within the colonic tissue. Colonic cyclooxygenase 2 levels were also dramatically suppressed by BRB treatment, with a concomitant decrease in the plasma prostaglandin E? (276 versus 34 ng/ml). These findings demonstrate a potent anti-inflammatory effect of BRB during DSS-induced colonic injury, supporting its possible therapeutic or preventive role in the pathogenesis of UC and related neoplastic events. PMID:21098643

  8. Effects of pyriproxyfen spray, powder, and oral bait treatments on the relative abundance of fleas (Siphonaptera: Ceratophyllidae) in black-tailed prairie dog (Rodentia: Sciuridae) towns.

    PubMed

    Karhu, R; Anderson, S

    2000-11-01

    Separate black-tailed prairie dog, Cynomys ludovicianus (Ord), towns on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were treated with technical pyriproxyfen (Nylar) using spray, powder, and oral bait carriers. Direct combing methods (1997 and 1998) and burrow flagging (1998) were used to estimate relative abundance of the plague vector Oropsylla hirsuta (Baker). Pyriproxyfen spray (0.05%) and powder (0.05%) did not significantly reduce (P > 0.05) O. hirsuta abundance. Pyriproxyfen bait, when applied every 4 wk at a concentration of 286 mg/50 g bait, significantly reduced (P < or = 0.05) O. hirsuta infesting prairie dogs, 4 mo after initial treatment. However, flea populations had recovered to pretreatment levels by the following summer (July 1999). PMID:11126542

  9. Effect of Cu{sup 2+} and Ni{sup 2+} substitution at the Mn site in (La{sub 0.63}Ca{sub 0.37})MnO{sub 3}: A neutron powder diffraction investigation

    SciTech Connect

    Martinelli, A., E-mail: alberto.martinelli@spin.cnr.it [CNR-SPIN, C.so Perrone 24, 16152 Genova (Italy); Ferretti, M. [CNR-SPIN, C.so Perrone 24, 16152 Genova (Italy); Dipartimento di Chimica e Chimica Industriale, Universit di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Castellano, C. [Universit degli Studi di Milano, Dipartimento di Chimica Strutturale e Stereochimica Inorganica, Via G. Venezian 21, 20133 Milano (Italy); Cimberle, M.R. [IMEM-CNR, Via Dodecaneso 33, 16146 Genova (Italy); Ritter, C. [Institute LaueLangevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9 (France)

    2013-04-15

    The crystal and magnetic structures of the (La{sub 0.63}Ca{sub 0.37})(Mn{sub 1?x}TM{sub x})O{sub 3} compounds (x=0.00, 0.03, 0.08; TM=Cu{sup 2+}, Ni{sup 2+}) were investigated between 5 K and 300 K by means of dc magnetic measurements and neutron powder diffraction analysis followed by Rietveld refinement. Both substituting cations lead to a reduction of the long range ferromagnetic ordering temperature; ferromagnetism is strongly suppressed in the 8% Cu-substituted sample, where long- and short-range FM magnetic orders coexist together with short-range A-type AFM order. This particular feature can be related to the JahnTeller character of Cu{sup 2+}, absent in Ni{sup 2+}, and suggests the occurrence of a quantum critical point in the (La{sub 0.63}Ca{sub 0.37})(Mn{sub 1?x}Cu{sub x})O{sub 3} system. - Graphical abstract: Rietveld refinement plot of (La{sub 0.63}Ca{sub 0.37})(Mn{sub 0.92}Cu{sub 0.08})O{sub 3} showing in the inset the coexistence of broad A-type AFM peaks with FM ones. Highlights: ? (La{sub 0.63}Ca{sub 0.37})MnO{sub 3} was substituted with Ni and Cu. ? Neutron powder diffraction and Rietveld refinement were carried out. ? A quantum critical point possibly occurs in the (La{sub 0.63}Ca{sub 0.37})(Mn{sub 1?x}Cu{sub x})O{sub 3} system.

  10. Effects of pyriproxyfen spray, powder, and oral bait treatments on the relative abundance of nontarget arthropods of black-tailed prairie dog (Rodentia: Sciuridae) towns.

    PubMed

    Karhu, R R; Anderson, S H

    2000-07-01

    Separate black-tailed prairie dog, Cynomys ludovicianus (Ord), towns on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were treated with technical pyriproxyfen (Nylar) spray, powder, and oral bait. The treatments were applied to reduce relative abundance of the plague vector Oropsylla hirsuta (Baker). Because pyriproxyfen is a juvenile hormone analog, we were also concerned with the effects of the treatments on nontarget arthropods, which is the focus of this study. Pitfall traps and sweep net sampling were used to measure relative abundance of arthropod populations pre- and posttreatment. Nontarget arthropod sampling produced a large number of statistical comparisons that indicated significant declines (P < 0.05) in relative arthropod abundance. Many of the significant declines were probably because of natural fluctuations in arthropod populations rather than treatment effects. Because arthropod populations appeared to fluctuate randomly, we only made inferences about highly significant (P < 0.001) declines. In doing so, we hoped to abate some of the confusion created by the natural fluctuation in arthropod abundance and increase our chance of correctly attributing a population reduction to a treatment effect. Only Homoptera at the pyriproxyfen powder site exhibited highly significant reductions that appeared to be attributed to the treatments. Pyriproxyfen spray treatments did not significantly reduce relative arthropod abundance. PMID:10916304

  11. Fatal contact shot to the chest caused by the gas jet from a muzzle-loading pistol discharging only black powder and no bullet: case study and experimental simulation of the wounding effect.

    PubMed

    Groe Perdekamp, Markus; Glardon, Matthieu; Kneubuehl, Beat P; Bielefeld, Lena; Nadjem, Hadi; Pollak, Stefan; Pircher, Rebecca

    2015-01-01

    In modern medico-legal literature, only a small number of publications deal with fatal injuries from black powder guns. Most of them focus on the morphological features such as intense soot soiling, blast tattooing and burn effects in close-range shots or describe the wound ballistics of spherical lead bullets. Another kind of "unusual" and potentially lethal weapons are handguns destined for firing only blank cartridges such as starter and alarm pistols. The dangerousness of these guns is restricted to very close and contact range shots and results from the gas jet produced by the deflagration of the propellant. The present paper reports on a suicide committed with a muzzle-loading percussion pistol cal. 45. An unusually large stellate entrance wound was located in the precordial region, accompanied by an imprint mark from the ramrod and a faint greenish discoloration (apparently due to the formation of sulfhemoglobin). Autopsy revealed an oversized powder cavity, multiple fractures of the anterior thoracic wall as well as ruptures of the heart, the aorta, the left hepatic lobe and the diaphragm. In total, the zone of mechanical destruction had a diameter of approx. 15 cm. As there was no exit wound and no bullet lodged in the body, the injury was caused exclusively by the inrushing combustion gases of the propellant (black powder) comparable with the gas jet of a blank cartridge gun. In contact shots to ballistic gelatine using the suicide's pistol loaded with black powder but no projectile, the formation of a nearly spherical cavity could be demonstrated by means of a high-speed camera. The extent of the temporary cavity after firing with 5 g of black powder roughly corresponded to the zone of destruction found in the suicide's body. PMID:25119685

  12. Cheap, Gram-Scale Fabrication of BN Nanosheets via Substitution Reaction of Graphite Powders and Their Use for Mechanical Reinforcement of Polymers

    PubMed Central

    Liu, Fei; Mo, Xiaoshu; Gan, Haibo; Guo, Tongyi; Wang, Xuebin; Chen, Bin; Chen, Jun; Deng, Shaozhi; Xu, Ningsheng; Sekiguchi, Takashi; Golberg, Dmitri; Bando, Yoshio

    2014-01-01

    As one of the most important two-dimensional (2D) materials, BN nanosheets attracted intensive interest in the past decade. Although there are many methods suitable for the preparation of BN sheets, finding a cheap and nontoxic way for their mass and high-quality production is still a challenge. Here we provide a highly effective and cheap way to synthesize gram-scale-level well-structured BN nanosheets from many common graphite products as source materials. Single-crystalline multi-layered BN sheets have a mean lateral size of several hundred nanometers and a thickness ranging from 5?nm to 40?nm. Cathodoluminescence (CL) analysis shows that the structures exhibit a near band-edge emission and a broad emission band from 300?nm to 500?nm. Utilization of nanosheets for the reinforcement of polymers revealed that the Young's modulus of BN/PMMA composite had increased to 1.56?GPa when the BN's fraction was only 2 wt.%, thus demonstrating a 20% gain compared to a blank PMMA film. It suggests that the BN nanosheet is an ideal mechanical reinforcing material for polymers. In addition, this easy and nontoxic substitution method may provide a universal route towards high yields of other 2D materials. PMID:24572725

  13. Cation substitution in synthetic meridianiite (MgSO411H2O) I: X-ray powder diffraction analysis of quenched polycrystalline aggregates

    NASA Astrophysics Data System (ADS)

    Fortes, A. Dominic; Browning, Frank; Wood, Ian G.

    2012-05-01

    Meridianiite, MgSO411H2O, is the most highly hydrated phase in the binary MgSO4-H2O system. Lower hydrates in the MgSO4-H2O system have end-member analogues containing alternative divalent metal cations (Ni2+, Zn2+, Mn2+, Cu2+, Fe2+, and Co2+) and exhibit extensive solid solution with MgSO4 and with one another, but no other undecahydrate is known. We have prepared aqueous MgSO4 solutions doped with these other cations in proportions up to and including the pure end-members. These liquids have been solidified into fine-grained polycrystalline blocks of metal sulfate hydrate + ice by rapid quenching in liquid nitrogen. The solid products have been characterised by X-ray powder diffraction, and the onset of partial melting has been quantified using a thermal probe. We have established that of the seven end-member metal sulfates studied, only MgSO4 forms an undecahydrate; ZnSO4 forms an orthorhombic heptahydrate (synthetic goslarite), MnSO4, FeSO4, and CoSO4 form monoclinic heptahydrates (syn. mallardite, melanterite, bieberite, respectively), and CuSO4 crystallises as the well-known triclinic pentahydrate (syn. chalcanthite). NiSO4 forms a new hydrate which has been indexed with a triclinic unit cell of dimensions a = 6.1275(1) , b = 6.8628(1) , c = 12.6318(2) , ? = 92.904(2), ? = 97.678(2), and ? = 96.618(2). The unit-cell volume of this crystal, V = 521.74(1) 3, is consistent with it being an octahydrate, NiSO48H2O. Further analysis of doped specimens has shown that synthetic meridianiite is able to accommodate significant quantities of foreign cations in its structure; of the order 50 mol. % Co2+ or Mn2+, 20-30 mol. % Ni2+ or Zn2+, but less than 10 mol. % of Cu2+ or Fe2+. In three of the systems we examined, an `intermediate' phase occurred that differed in hydration state both from the Mg-bearing meridianiite end-member and the pure dopant end-member hydrate. In the case of CuSO4, we observed a melanterite-structured heptahydrate at Cu/(Cu + Mg) = 0.5, which we identify as synthetic alpersite [(Mg0.5Cu0.5)SO47H2O)]. In the NiSO4- and ZnSO4-doped systems we characterised an entirely new hydrate which could also be identified to a lesser degree in the CuSO4- and the FeSO4-doped systems. The Ni-doped substance has been indexed with a monoclinic unit-cell of dimensions a = 6.7488(2) , b = 11.9613(4) , c = 14.6321(5) , and ? = 95.047(3), systematic absences being indicative of space-group P21/ c with Z = 4. The unit-cell volume, V = 1,176.59(5) 3, is consistent with it being an enneahydrate [i.e. (Mg0.5Ni0.5)SO49H2O)]. Similarly, the new Zn-bearing enneahydrate has refined unit cell dimensions of a = 6.7555(3) , b = 11.9834(5) , c = 14.6666(8) , ? = 95.020(4), V = 1,182.77(7) 3, and the new Fe-bearing enneahydrate has refined unit cell dimensions of a = 6.7726(3) , b = 12.0077(3) , c = 14.6920(5) , ? = 95.037(3), and V = 1,190.20(6) 3. The observation that synthetic meridianiite can form in the presence of, and accommodate significant quantities of other ions increases the likelihood that this mineral will occur naturally on Marsand elsewhere in the outer solar systemin metalliferous brines.

  14. Magnetic properties of substituted barium ferrite powders

    SciTech Connect

    Gruskova, A. [Slovak Univ. of Technology, Bratislava (Slovakia). Dept. of Electrotechnology] [Slovak Univ. of Technology, Bratislava (Slovakia). Dept. of Electrotechnology

    1994-03-01

    Hexagonal barium ferrites were prepared using the citrate method. Cobalt and titanium were added in the amounts x from 0.2 to 1.1 ion/f.u. related to the formula BaCo{sub x}Ti{sub x}Fe{sub 12{minus}2x}O{sub 19}. The heat treatment has been applied in three steps of 550 C/5 hrs, 850 C/2 hrs and 1,100 C/2 hrs. The following magnetic properties have been achieved: H{sub c} {approximately} 80 kA/m, J{sub s} {approximately} 120 {times} 10{sup {minus}6} Tkg{sup {minus}1} m{sup 3}, and J{sub r} {approximately} 60 {times} 10{sup {minus}6} Tkg{sup {minus}1} m{sup 3} in the composition for which x is equal to 0.5 ion/f.u. The magnetic parameters have been measured by the vibration magnetometer.

  15. Mystery Powders

    NSDL National Science Digital Library

    American Chemical Society

    2000-01-01

    In this activity on page 2 of the PDF, learners conduct chemical tests on certain powders used in cooking. After completing the tests, learners try to figure out the identity of a mystery powder. Learners record their observations on a chart. Note: you will need an adult helper for this activity.

  16. Revealing the powdering methods of black makeup in Ancient Egypt by fitting microstructure based Fourier coefficients to the whole x-ray diffraction profiles of galena

    Microsoft Academic Search

    T. Ungr; P. Martinetto; G. Ribrik; E. Dooryhe; Ph. Walter; M. Anne

    2002-01-01

    Galena (PbS) is a major ingredient in ancient Egyptian eye makeup. The microstructure of PbS in Egyptian cosmetic powders is used as a fingerprint and is matched with the microstructures produced artificially in geological galena minerals. The microstructure of PbS is determined by x-ray diffraction peak profile analysis in terms of dislocation density, crystallite size, and size distribution. High-resolution powder

  17. Skin Substitutes

    PubMed Central

    Howe, Nicole; Cohen, George

    2014-01-01

    In a relatively short timespan, a wealth of new skin substitutes made of synthetic and biologically derived materials have arisen for the purpose of wound healing of various etiologies. This review article focuses on providing an overview of skin substitutes including their indications, contraindications, benefits, and limitations. The result of this overview was an appreciation of the vast array of options available for clinicians, many of which did not exist a short time ago. Yet, despite the rapid expansion this field has undergone, no ideal skin substitute is currently available. More research in the field of skin substitutes and wound healing is required not only for the development of new products made of increasingly complex biomolecular material, but also to compare the existing skin substitutes. PMID:25371771

  18. Solvent substitution

    SciTech Connect

    Not Available

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

  19. X-ray powder diffraction, vibration and thermal studies of [A{sub 0.92}(NH{sub 4}){sub 0.08}]{sub 2}TeCl{sub 4}Br{sub 2} with A = Cs, Rb: Influence of mixed cationic and anionic substitutions

    SciTech Connect

    Aribia, W. Ben; Abdelmouleh, M. [Laboratoire des Sciences des Materiaux et de l'environnement, Universite de Sfax, Faculte des Sciences de Sfax, 3018 (Tunisia)] [Laboratoire des Sciences des Materiaux et de l'environnement, Universite de Sfax, Faculte des Sciences de Sfax, 3018 (Tunisia); Kabadou, A., E-mail: kabadouahlem@yahoo.fr [Laboratoire des Sciences des Materiaux et de l'environnement, Universite de Sfax, Faculte des Sciences de Sfax, 3018 (Tunisia); Van Der Lee, A. [Institut Europeen des Membranes (UMR 5635), Universite de Montpellier II, cc 047, Place E. Montpellier (France)] [Institut Europeen des Membranes (UMR 5635), Universite de Montpellier II, cc 047, Place E. Montpellier (France)

    2012-05-15

    Graphical abstract: The structures of [A{sub 0.92}(NH{sub 4}){sub 0.08}]{sub 2}TeCl{sub 4}Br{sub 2} with A = Cs, Rb belong to the tetragonal {beta}-K{sub 2}SnCl{sub 6} structure type. Highlights: Black-Right-Pointing-Pointer The two new compound crystallises in P4/mnc tetragonal space group. Black-Right-Pointing-Pointer The structure is considered as isolated octahedred TeCl{sub 4}Br{sup 2-}. Black-Right-Pointing-Pointer The octahedra connected by ionic and hydrogen bonding through the Cs/Rb or N atoms. Black-Right-Pointing-Pointer A DTA/TGA experiment reveals one endothermic peak at 780 K for these compounds. Black-Right-Pointing-Pointer One endothermic peak is detected at around 213 K by DSC experiment. -- Abstract: The crystal structures of [A{sub 0.92}(NH{sub 4}){sub 0.08}]{sub 2}TeCl{sub 4}Br{sub 2} with A = Cs, Rb have been determined using X-ray powder diffraction techniques. The two compounds crystallize in the tetragonal space group P4/mnc, with the unit cell parameters: a = 7.452(1) Angstrom-Sign , c = 10.544(3) Angstrom-Sign , Z = 2 and a = 7.315(2) Angstrom-Sign , c = 10.354(4) Angstrom-Sign , Z = 2 in the presence of Cs and Rb, respectively. These two compounds have an antifluorite-type arrangement of NH{sub 4}{sup +}/Rb{sup +}/Cs{sup +} and octahedral TeCl{sub 4}Br{sub 2}{sup 2-} anions. The stability of these structure is by ionic and hydrogen bonding contacts: A Midline-Horizontal-Ellipsis Cl, A Midline-Horizontal-Ellipsis Br and N-H Midline-Horizontal-Ellipsis Cl, N-H Midline-Horizontal-Ellipsis Br. The different vibrational modes of these powders were analysed by FTIR and Raman spectroscopic studies. A DTA/TGA experiment reveals one endothermic peak at 780 K implicating the decomposition of the sample. At low temperature, one endothermic peak in thermal behavior is detected at around 213 K by DSC experiment. This transition was confirmed by dielectric measurements.

  20. A study of a tissue equivalent gelatine based tissue substitute

    SciTech Connect

    Spence, J.L.

    1992-11-01

    A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to a liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it`s usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.

  1. A study of a tissue equivalent gelatine based tissue substitute

    SciTech Connect

    Spence, J.L.

    1992-11-01

    A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to a liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it's usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.

  2. The role of substitutional boron in carbon oxidation: Inhibitor and catalyst!

    SciTech Connect

    Radovic, L.R.; Karra, M.; Thrower, P.A. [Penn State Univ., University Park, PA (United States)

    1996-10-01

    Boron is considered to be one of the very few promising candidates for chemical protection of carbon/carbon composite materials against oxidation. The conventional wisdom is that boron inhibits carbon oxidation. Its inhibiting effect can be manifested in three different ways: (1) Substitutional boron enhances the graphitization of carbon. (2) As the surface carbon atoms are consumed, substitutional boron forms an oxide surface film, which acts as an O{sub 2} diffusion harrier and an active site blocker. (3) Substitutional boron redistributes the {pi} electrons in the basal plane (graphene layer), lowers the Fermi level of carbon, and hence presumably inhibits the desorption of CO and CO{sub 2}. This last mode of inhibition is of great fundamental interest; it had not been verified in the past. Upon closer examination of some early studies, its closer scrutiny is wan-anted. We provide such a scrutiny in the present communication. Three widely differing carbon materials were used: a heat-treated ({open_quote}graphitized{close_quote}) carbon black (Graphon), Saran char and a glassy carbon. Boron was introduced substitutionally into the quasi-graphitic lattice by heating these carbons, physically mixed with boron powder. Isothermal carbon oxidation experiments were performed. In selected cases, the reactive surface area of the carbons was determined.

  3. Powder treatment process

    DOEpatents

    Weyand, J.D.

    1988-02-09

    Disclosed are: (1) a process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder. 2 figs.

  4. Powder treatment process

    DOEpatents

    Weyand, John D. (Greensburg, PA)

    1988-01-01

    (1) A process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder.

  5. Borate substituted ettringites

    SciTech Connect

    Csetenyi, L.J.; Glasser, F.P. [Univ. of Aberdeen, Old Aberdeen, Scotland (United Kingdom)

    1993-12-31

    The setting of cement is adversely affected by soluble borates. To reduce interference, the extent to which borate can be insolubilized has been investigated. One specific mechanism of insolubilization is by inclusion into ettringite. Ettringite, Ca{sub 6}Al{sub 2}(SO{sub 4}){sub 3}(OH){sub 12}{center_dot}26H{sub 2}O, is a normal and stable constituent of Portland cement. It has an open but non-zeolitic framework. Borate can substitute partially or fully for sulfate. Formation conditions, solubility and stability of borate ettringites, Ca{sub 6}Al{sub 2}(BO{sub 4}){sub 2-4}(OH,O){sub 12}{center_dot}26H{sub 2}O, are characterized using XRD, IR, DTA, and SEM. The potential durability of borate ettringites in a repository environment have been assessed by exposing it to Na-sulfate and Na-carbonate attack at different concentrations. Ion exchange occurs; back substitution of borate by sulfate is incomplete; high carbonate concentrations can, however, decompose borate ettringite. On heat treatment up to 85{degrees}C the crystalline morphology and the OH arrangement of the structure are altered, but the X-ray powder pattern, and hence its structural framework are largely unaffected. It is concluded that ettringite has potential to reduce the solubility of borate.

  6. Lynching and the Death Penalty in Kentucky, 18661934: Substitution or Supplement?

    Microsoft Academic Search

    Thomas J. Keil; Gennaro F. Vito

    2009-01-01

    Using multivariate techniques, this article reanalyzes data from the Espy file to test a hypothesis by historian George Wright. In Racial Violence in Kentucky, Wright concludes that legal executions became a functional substitute for Black lynchings in Kentucky. Wright assumes that executions formed a legal substitute for lynchings of Blacks. For this reason, Black lynchings declined dramatically during the 1920s

  7. Location and oxidation state of iron in Fe-substituted CuInS{sub 2} chalcopyrites

    SciTech Connect

    Burnett, Johanna D. [Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282 (United States); Xu Tianhong; Sorescu, Monica [Department of Physics, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282 (United States); Strohmeier, Brian R. [RJ Lee Group, Inc., 350 Hochberg Rd., Monroeville, PA 15146 (United States); Thermo Fisher Scientific, 5225 Verona Road, Madison, WI 53711 (United States); Sturgeon, Jacqueline [RJ Lee Group, Inc., 350 Hochberg Rd., Monroeville, PA 15146 (United States); Gourdon, Olivier [Chemical and Engineering Materials Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Baroudi, Kristen; Yao Jinlei [Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282 (United States); Aitken, Jennifer A., E-mail: aitkenj@duq.edu [Department of Chemistry and Biochemistry, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282 (United States)

    2013-01-15

    CuIn{sub 1-x}Fe{sub x}S{sub 2}(x=0-0.30) was synthesized via high-temperature, solid-state synthesis. Phase-pure materials were found in samples where x=0-0.15, after which a secondary phase became apparent. The materials were characterized with the use of X-ray powder diffraction (XRPD), and Reitveld refinement revealed a linear decrease in unit cell volume as the amount of iron substitution increases in accordance with Vegard's Law. Inductively coupled plasma (ICP) confirms that the actual stoichiometry is close to the nominal composition of the materials. The temperature for both the chalcopyrite-to-sphalerite and the sphalerite-to-wurtzite phase transitions decreases with increasing iron substitution for indium. These findings suggest that the Fe is being randomly incorporated into the crystal structure of the CuInS{sub 2}. X-ray photoelectron spectroscopy (XPS) measurements were used to determine the oxidation state of the ions (Cu{sup 1+}, In{sup 3+,} and S{sup 2-}), and Fe{sup 57} Moessbauer spectroscopy verified that the iron is in the 3{sup +} oxidation state. Band gaps of the solid solution were estimated to be in the range of 0.70-0.85 eV. Rietveld refinement of neutron diffraction data indicates that the iron is occupying the In site within the chalcopyrite structure. - Graphical abstract: CuIn{sub 1-x}Fe{sub x}S{sub 2} samples were prepared by solid-state synthesis. X-ray photoelectron spectroscopy and Moessbauer spectroscopy indicate Cu{sup +}, In{sup 3+}, Fe{sup 3+} and S{sup 2-} in the samples. Rietveld refinement of neutron powder diffraction data shows Fe{sup 3+} residing on the indium site. The band gaps of the iron-containing samples decrease to {approx}0.7 eV. Highlights: Black-Right-Pointing-Pointer X-ray photoelectron spectroscopy confirms the presence of Cu{sup +}, In{sup 3+} and S{sup 2-}. Black-Right-Pointing-Pointer Moessbauer spectroscopy indicates the presence of Fe{sup 3+}. Black-Right-Pointing-Pointer Rietveld refinement of neutron powder diffraction data shows iron on the indium site. Black-Right-Pointing-Pointer The band gap decreases to {approx}0.7 eV with only 5% iron substitution. Black-Right-Pointing-Pointer Additional characterization is reported.

  8. Characterization of Fine Powders

    NASA Astrophysics Data System (ADS)

    Krantz, Matthew; Zhang, Hui; Zhu, Jesse

    Fine powders are used in many applications and across many industries such as powdered paints and pigments, ceramics, petrochemicals, plastics, pharmaceuticals, and bulk and fine chemicals, to name a few. In addition, fine powders must often be handled as a waste by-product, such as ash generated in combustion and gasification processes. In order to correctly design a process and process equipment for application and handling of powders, especially fine powders, it is essential to understand how the powder would behave. Many characterization techniques are available for determining the flow properties of powders; however, care must be taken in selecting the most appropriate technique(s).

  9. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Substituted pyridine azo substituted phenyl. 721.8780 Section 721.8780 ...Substituted pyridine azo substituted phenyl. (a) Chemical substance and significant...as substituted pyridine azo substituted phenyl (PMNs P-96-767 and...

  10. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Substituted pyridine azo substituted phenyl. 721.8780 Section 721.8780 ...Substituted pyridine azo substituted phenyl. (a) Chemical substance and significant...as substituted pyridine azo substituted phenyl (PMNs P-96-767 and...

  11. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Substituted pyridine azo substituted phenyl. 721.8780 Section 721.8780 ...Substituted pyridine azo substituted phenyl. (a) Chemical substance and significant...as substituted pyridine azo substituted phenyl (PMNs P-96-767 and...

  12. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Substituted pyridine azo substituted phenyl. 721.8780 Section 721.8780 ...Substituted pyridine azo substituted phenyl. (a) Chemical substance and significant...as substituted pyridine azo substituted phenyl (PMNs P-96-767 and...

  13. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Substituted pyridine azo substituted phenyl. 721.8780 Section 721.8780 ...Substituted pyridine azo substituted phenyl. (a) Chemical substance and significant...as substituted pyridine azo substituted phenyl (PMNs P-96-767 and...

  14. Precision powder feeder

    DOEpatents

    Schlienger, M. Eric (Albuquerque, NM); Schmale, David T. (Albuquerque, NM); Oliver, Michael S. (Sandia Park, NM)

    2001-07-10

    A new class of precision powder feeders is disclosed. These feeders provide a precision flow of a wide range of powdered materials, while remaining robust against jamming or damage. These feeders can be precisely controlled by feedback mechanisms.

  15. 40 CFR Appendix S to Subpart G of... - Substitutes Listed in the September 19, 2012 Final Rule, Effective December 18, 2012.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Use Conditions End-Use Substitute Decision Conditions Further information Total Flooding Powdered Aerosol F (KSA) as a substitute for Halon 1301 Acceptable subject to use conditions For use only in normally unoccupied...

  16. 40 CFR Appendix S to Subpart G of... - Substitutes Listed in the September 19, 2012 Final Rule, Effective December 18, 2012.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Use Conditions End-Use Substitute Decision Conditions Further information Total Flooding Powdered Aerosol F (KSA) as a substitute for Halon 1301 Acceptable subject to use conditions For use only in normally unoccupied...

  17. Aluminum powder metallurgy processing

    SciTech Connect

    Flumerfelt, J.F.

    1999-02-12

    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

  18. Natural Stone Waste Powders Applied to SCC Mix Design

    Microsoft Academic Search

    M. Hunger; H. J. H. Brouwers

    2008-01-01

    In order to comply with current trends concerning sustainability, saving of primary materials and energy\\u000asavings, this paper addresses Eco-concrete. The major focus thereby is on the increased efficiency of cement\\u000ause. Applying a new mix design method for concrete, cement contents can be decreased and partially be substituted\\u000aby other fine powders, preferentially by waste powders which have no

  19. Electrical Properties of Nb-, Ga-, and Y-Substituted Nanocrystalline Anatase TiO2 Prepared by Hydrothermal Synthesis

    E-print Network

    Poeppelmeier, Kenneth R.

    103 S/cm in heat-treated powders (520C, 1 h). In contrast, substitution with Ga3+ and Y3+ had University, Evanston, IL 60208 Nanocrystalline anatase titanium dioxide powders were pro- duced+ with the intention of creating acceptor or donor states, respectively. The electrical conductivity of each powder

  20. Structural and magnetic characterisation of CoSb{sub 2}O{sub 4}, and the substitution of Pb{sup 2+} for Sb{sup 3+}

    SciTech Connect

    Laune, Benjamin P. de [School of Chemistry, University of Birmingham, Birmingham B15 2TT (United Kingdom); Greaves, Colin, E-mail: c.greaves@bham.ac.uk [School of Chemistry, University of Birmingham, Birmingham B15 2TT (United Kingdom)

    2012-03-15

    The nuclear and magnetic structures of the synthetic schafarzikite related material CoSb{sub 2}O{sub 4} have been determined from neutron powder diffraction data. The compound is tetragonal (P4{sub 2}/mbc) with refined lattice constants at 300 K of, a=8.49340(9) A, c=5.92387(8) A. The magnetic ordering is shown to be consistent with a C mode with moments aligned along [0 0 1]. Magnetic susceptibility measurements indicate a canted antiferromagnetic ground state, for which the ferromagnetic component shows unusually high coercivity. The thermal stability of CoSb{sub 2}O{sub 4} in air is reported. The substitution of Pb{sup 2+} for Sb{sup 3+} has been investigated and found to cause oxidation of both Co{sup 2+} to Co{sup 3+} and Sb{sup 3+} to Sb{sup 5+}. - Graphical Abstract: Structural changes on substitution of Pb{sup 2+} ions for Sb{sup 3+} ions in CoSb{sub 2}O{sub 4}. Highlights: Black-Right-Pointing-Pointer The structural details of CoSb{sub 2}O{sub 4} are reported for the first time. Black-Right-Pointing-Pointer The magnetic structure of CoSb{sub 2}O{sub 4} are reported for the first time. Black-Right-Pointing-Pointer The ordered magnetic structure has a canted antiferromagnetic arrangement. Black-Right-Pointing-Pointer The ferromagnetic component of the ordered arrangement has high coercivity. Black-Right-Pointing-Pointer Pb{sup 2+} can substitute for Sb{sup 3+} and oxidation of both Co{sup 2+} and Sb{sup 3+} occurs.

  1. Multiple feed powder splitter

    DOEpatents

    Lewis, Gary K. (Los Alamos, NM); Less, Richard M. (Los Alamos, NM)

    2002-01-01

    A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

  2. Which Powder is It?

    NSDL National Science Digital Library

    Sciencenter

    2014-08-27

    In this chemistry challenge, learners identify an unknown white powder by comparing it with common household powders. Learners first explore what happens when baking soda, baking powder, and washing soda are mixed with water, vinegar, and PHTH (the indicator phenolphthalein mixed with alcohol and water). Learners then work to identify the unknown based on how it reacts with the known solutions. This is a simplified form of "qualitative analysis," which was historically an important approach chemists used for identifying unknown samples.

  3. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-05

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of ternary mixtures consisting of: Ni powder, Cu powder, and Al powder, Ni powder, Cr powder, and Al powder; Ni powder, W powder and Al powder; Ni powder, V powder, and Al powder; Ni powder, Mo powder, and Al powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  4. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...benzenesulfonamide alkylphenyl substituted phenyl substituted carbonyl- (PMN...

  5. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...benzenesulfonamide alkylphenyl substituted phenyl substituted carbonyl- (PMN...

  6. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...benzenesulfonamide alkylphenyl substituted phenyl substituted carbonyl- (PMN...

  7. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...benzenesulfonamide alkylphenyl substituted phenyl substituted carbonyl- (PMN...

  8. 40 CFR 721.1620 - Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...Benzenesulfonamide, alkylphenyl substituted phenyl substituted carbonyl- (generic...benzenesulfonamide alkylphenyl substituted phenyl substituted carbonyl- (PMN...

  9. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

  10. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

  11. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

  12. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic...alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

  13. Implantable bone substitute materials.

    PubMed

    Hanft, J R; Sprinkle, R W; Surprenant, M S; Werd, M B

    1995-07-01

    This article focuses on materials used as bone substitutes. The materials may be used as substitutes for autografts or, in some cases, along with autografts. Each material has unique properties that may be beneficial for specific applications. Some future developments in bone substitute materials are also discussed. PMID:7553534

  14. Morphology and composition of Ni-Co electrodeposited powders

    SciTech Connect

    Maksimovic, V.M., E-mail: vesnam@vinca.rs [Institute of Nuclear Sciences, 'Vinca', University of Belgrade, 11001 Belgrade, P. O. Box 522 (Serbia); Lacnjevac, U.C. [Institute for Multidisciplinary research, University of Belgrade, P.O. Box 33, 11030 Belgrade (Serbia); Stoiljkovic, M.M. [Institute of Nuclear Sciences, 'Vinca', University of Belgrade, 11001 Belgrade, P. O. Box 522 (Serbia); Pavlovic, M.G. [Institute of Electrochemistry, ICTM, University of Belgrade, 11000 Belgrade, Njegoseva 12 (Serbia); Jovic, V.D. [Institute for Multidisciplinary research, University of Belgrade, P.O. Box 33, 11030 Belgrade (Serbia)

    2011-12-15

    The morphology, phase and chemical composition of Ni-Co alloy powders electrodeposited from an ammonium sulfate-boric acid containing electrolyte with different ratio of Ni/Co ions were investigated. The ratios of Ni/Co ions were 1/1, 1/2 and 1/3. The morphology, chemical composition and phase composition of the electrodeposited alloy powders were investigated using AES, SEM, EDS and XRD analysis. Composition of the electrolyte, i.e. the ratio of Ni/Co concentrations was found to influence both, the alloy phase composition and the morphology of Ni-Co alloy powders. At the highest ratio of Ni/Co = 1/1 concentrations typical 2D fern-like dendritic particles were obtained. With a decrease of Ni/Co ions ratio among 2D fern-like dendrites, 3D dendrites and different agglomerates were obtained. X-ray diffraction studies showed that the alloy powders mainly consisted of the face-centered cubic {alpha}-nickel phase and hexagonal close-packed {epsilon}-cobalt phase and minor proportions of face-centered cubic {alpha}-cobalt phase. The occurrence of the latter phase was observed only in the alloy powder with the higher cobalt concentration in electrolyte. The electrodeposition of Ni-Co powders occurred in an anomalous manner. - Highlights: Black-Right-Pointing-Pointer Ni-Co alloys powders were successfully electrodeposited. Black-Right-Pointing-Pointer Composition of the electrolyte (Ni/Co ions ratio) was found to influence on morphology of powders. Black-Right-Pointing-Pointer The electrodeposition of Ni-Co powders occurred in an anomalous manner.

  15. Single crystalline and rare earth substituted La{sub 2}RuO{sub 5} investigated by x-ray diffraction and EXAFS spectroscopy

    SciTech Connect

    Riegg, S., E-mail: stefan.riegg@physik.uni-augsburg.de [Experimental Physics V, Center for Electronic Correlations and Magnetism, University of Augsburg, D - 86135 Augsburg (Germany); Reller, A. [Resource Strategy, University of Augsburg, D - 86135 Augsburg (Germany); Ebbinghaus, S.G. [Solid State Chemistry, Martin-Luther University Halle-Wittenberg, D - 06099 Halle (Germany)

    2012-04-15

    Single crystals of La{sub 2}RuO{sub 5} were obtained from a BaCl{sub 2} flux. The structure was determined by single crystal x-ray diffraction and compared to earlier x-ray and neutron powder diffraction results. The local structures of Ru and La/Ln in pure La{sub 2}RuO{sub 5} and the rare earth substituted La{sub 2-x}Ln{sub x}RuO{sub 5} (Ln=Pr, Nd, Sm, Gd, Dy) polycrystalline samples were determined from the extended x-ray absorption fine structures (EXAFS) of the K- and L{sub III}-edges of Ru, La, and Ln, respectively. A four shell model was developed to reduce the number of refinable parameters in the fit of the EXAFS spectra. The distribution of the Ln-ions in the layered crystal structure was determined by a comparison of the coordination spheres obtained from the Ln-edges with the unsubstituted La{sub 2}RuO{sub 5}. Interatomic distances were compared to the values obtained from the single crystal diffraction and were found to agree very well. - Graphical abstract: The crystal structure of La{sub 2-x}Ln{sub x}RuO{sub 5} (Ln=Pr, Nd, Sm, Gd, Dy) is shown viewed along the c-axis. The alternating stacking of LaRuO{sub 4} and LnO layers leads to the formation of zig-zag layers of corner sharing RuO{sub 6} octahedra. The La sites in the LaRuO{sub 4} layers are represented by light blue spheres, while the La/Ln sites in the LnO layers are colored dark blue. EXAFS investigations reveal a cationic ordering with roughly 65% of the substituting Ln ions occupying the LnO layers. Highlights: Black-Right-Pointing-Pointer Structure determination of La{sub 2}RuO{sub 5} by single crystal x-ray diffraction. Black-Right-Pointing-Pointer Ru-K EXAFS investigations of La{sub 2-x}Ln{sub x}RuO{sub 5} powder samples. Black-Right-Pointing-Pointer EXAFS of La and Ln in La{sub 2-x}Ln{sub x}RuO{sub 5} powder samples using K- and L{sub III}-absorption edges. Black-Right-Pointing-Pointer Good agreement of EXAFS results and crystal structure data despite low symmetry space group. Black-Right-Pointing-Pointer Observed partial cationic ordering of the inserted Ln on the two La sites.

  16. Sintering titanium powders

    SciTech Connect

    Gerdemann, Stephen J.; Alman, David E.

    2005-09-01

    Recently, there has been renewed interest in low-cost titanium. Near-net-shape powder metallurgy offers the potential of manufacturing titanium articles without costly and difficult forming and machining operations; hence, processing methods such as conventional press-and-sinter, powder forging and powder injection molding are of interest. The sintering behavior of a variety of commercial and experimental titanium powders was studied. Commercial powders were acquired that were produced different routes: (i) sponge fines from the primary titanium processing; (ii) via the hydride-dehydride process; and (iii) gas atomization. The influence of vacuum sintering time (0.5 to 32 hrs) and temperature (1200, 1275 or 1350C) on the microstructure (porosity present) of cold pressed powders was studied. The results are discussed in terms of the difference in powder characteristics, with the aim of identify the characteristics required for full density via press-and-sinter processing. Near-net-shape tensile bars were consolidated via cold pressed and sintered. After sintering, a sub-set of the tensile bars was hot-isostatic pressed (HIPed). The microstructure and properties of the bars were compared in the sintered and HIPed conditions.

  17. Compaction of Titanium Powders

    SciTech Connect

    Stephen J. Gerdemann; Paul D. Jablonski

    2010-11-01

    Accurate modeling of powder densification has been an area of active research for more than 60 years. The earliest efforts were focused on linearization of the data because computers were not readily available to assist with curve-fitting methods. In this work, eight different titanium powders (three different sizes of sponge fines <150 ?m, <75 ?m, and < 45 ?m; two different sizes of a hydride-dehydride [HDH] <75 ?m and < 45 ?m; an atomized powder; a commercially pure [CP] Ti powder from International Titanium Powder [ITP]; and a Ti 6 4 alloy powder) were cold pressed in a single-acting die instrumented to collect stress and deformation data during compaction. From these data, the density of each compact was calculated and then plotted as a function of pressure. The results show that densification of all the powders, regardless of particle size, shape, or chemistry, can be modeled accurately as the sum of an initial density plus the sum of a rearrangement term and a work-hardening term. These last two terms are found to be a function of applied pressure and take the form of an exponential rise.

  18. Compaction of Titanium Powders

    SciTech Connect

    Gerdemann, Stephen,J; Jablonski, Paul, J

    2011-05-01

    Accurate modeling of powder densification has been an area of active research for more than 60 years. The earliest efforts were focused on linearization of the data because computers were not readily available to assist with curve-fitting methods. In this work, eight different titanium powders (three different sizes of sponge fines<150 {micro}m,<75 {micro}m, and<45 {micro}m; two different sizes of a hydride-dehydride [HDH]<75 {micro}m and<45 {micro}m; an atomized powder; a commercially pure [CP] Ti powder from International Titanium Powder [ITP]; and a Ti 6 4 alloy powder) were cold pressed in a single-acting die instrumented to collect stress and deformation data during compaction. From these data, the density of each compact was calculated and then plotted as a function of pressure. The results show that densification of all the powders, regardless of particle size, shape, or chemistry, can be modeled accurately as the sum of an initial density plus the sum of a rearrangement term and a work-hardening term. These last two terms are found to be a function of applied pressure and take the form of an exponential rise.

  19. Stable powders made from photosensitive polycrystalline complexes of heterocyclic monomers and their polymers

    NASA Technical Reports Server (NTRS)

    Hodko, Dalibor (Inventor); Murphy, Oliver J. (Inventor); Hitchens, G. Duncan (Inventor)

    1999-01-01

    The present invention relates to a low electronic conductivity polymer composition having well dispersed metal granules, a stable powder made from photosensitive polycrystalline complexes of pyrrole, or its substituted derivatives and silver cations for making the polymer composition, and methods of forming the stable powder and polymer composition, respectively. A polycrystalline complex of silver and a monomer, such as pyrrole, its substituted derivatives or combinations thereof, is precipitated in the form of a stable photosensitive powder upon addition of the monomer to a solvent solution, such as toluene containing an electron acceptor. The photosensitive powder can be stored in the dark until needed. The powder may be dissolved in a solvent, cast onto a substrate and photopolymerized.

  20. Mystery Powder Investigation

    NSDL National Science Digital Library

    Rachel HallettNjuguna

    2012-07-27

    Students will use their skills as scientists to identify a mystery white powder. This lesson is a hands-on, engaging way to build students' understanding of physical and chemical properties of several common compounds.

  1. Talcum Powder and Cancer

    MedlinePLUS

    ... and risk of endometrial cancer in postmenopausal women. Cancer Causes Control . 2012;23:1673?1680. Gertig DM, Hunter ... Use of talcum powder and endometrial cancer risk. Cancer Causes Control . 2012;2:513?519. Rosenblatt KA, Weiss ...

  2. Gelcasting superalloy powders

    SciTech Connect

    Janney, M.A.

    1995-12-31

    Gelcasting is a process for forming inorganic powders into complex shapes. It was originally developed for ceramic powders. A slurry of powder and a monomer solution is poured in to mold and polymerized in-situ to form gelled parts. Typically, only 2-4 wt % Polymer is used. The process has both aqueous and nonaqueous versions. Gelcasting is a generic process and has been used to produce ceramic parts from over a dozen different ceramic compositions ranging from alumina-based refractories to high-performance silicon nitride. Recently, gelcasting has been applied to forming superalloy powders into complex shapes. This application has posed several challenges not previously encountered in ceramics. In particular, problems were caused by the larger particle size and the higher density of the particles. Additional problems were encountered with binder removal. How these problems were overcome will be described.

  3. POWDER COAT APPLICATIONS

    EPA Science Inventory

    The report discusses an investigation of critical factors that affect the use of powder coatings on the environment, cost, quality, and production. The investigation involved a small business representative working with the National Defense Center for Environmental Excellence (ND...

  4. Hepagene (PowderJect).

    PubMed

    Jones, Taff

    2002-07-01

    Celltech Group (formerly Medeva) developed Hepagene, a recombinant polyvalent vaccine with potential activity against hepatitis B virus infections [353474]. In September 2000, PowderJect acquired the product as part of its acquisition of Celltech's vaccine manufacturing business [381557]. In July 2001, PowderJect reported that evaluation was nearing completion. At this time, the company expected to launch the vaccine in the coming months [443490]. Hepagene is a polyvalent vaccine with S, pre-S1 and pre-S2 hepatitis B epitopes forming the basis of its antigenicity. Additionally, these surface markers have been glycosylated in order to resemble the live virus more closely [254780]. By June 2000, Celltech and PowderJect were evaluating Hepagene, utilizing PowderJect's needle-less injection technology [379536]. In December 1999, Lehman Brothers predicted that the product had a 50% chance of reaching the treatment (rather than prevention) market, with potential peak sales of US $600 million [352078]. PMID:12186276

  5. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-19

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  6. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-08-26

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  7. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-01-25

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  8. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goval, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-06-07

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  9. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2004-09-28

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  10. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2005-05-10

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  11. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-07-29

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  12. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2004-09-14

    A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  13. Synthesis of high surface area ZnO powder by continuous precipitation

    SciTech Connect

    Boz, Ismail, E-mail: ismailb@istanbul.edu.tr [Istanbul University, Faculty of Engineering, Department of Chemical Engineering, Avcilar, Istanbul 34320 (Turkey)] [Istanbul University, Faculty of Engineering, Department of Chemical Engineering, Avcilar, Istanbul 34320 (Turkey); Kaluza, Stefan [Laboratory of Industrial Chemistry, Ruhr-University Bochum, Universitaetsstr. 150, Bochum 44780 (Germany)] [Laboratory of Industrial Chemistry, Ruhr-University Bochum, Universitaetsstr. 150, Bochum 44780 (Germany); Boroglu, Mehtap Safak [Istanbul University, Faculty of Engineering, Department of Chemical Engineering, Avcilar, Istanbul 34320 (Turkey)] [Istanbul University, Faculty of Engineering, Department of Chemical Engineering, Avcilar, Istanbul 34320 (Turkey); Muhler, Martin [Laboratory of Industrial Chemistry, Ruhr-University Bochum, Universitaetsstr. 150, Bochum 44780 (Germany)] [Laboratory of Industrial Chemistry, Ruhr-University Bochum, Universitaetsstr. 150, Bochum 44780 (Germany)

    2012-05-15

    Graphical abstract: High surface area ZnO powders are synthesized by a low temperature continuous precipitation under ultrasonication. Urea is used as precipitating agent so that no contamination of ZnO powder emanating from precipitating agent, such as, alkalis, is observed. pH and type of precursor greatly affects the surface area and other properties. In this manuscript, we report a very simple and effective continuous precipitation to synthesize high surface area ZnO powder. Highlights: Black-Right-Pointing-Pointer The synthesis of high surface area ZnO powder was achieved at 90 Degree-Sign C in a continuous precipitation unit. Black-Right-Pointing-Pointer Continuous precipitation unit was ultrasonicated to improve final product homogeneity. Black-Right-Pointing-Pointer Precipitation intermediate, hydrozincite, was led to high surface area ZnO powder. Black-Right-Pointing-Pointer The synthesized ZnO nanoparticles had a rather uniform mesoporous structure. -- Abstract: Synthesis of high surface area ZnO powder was achieved by continuous precipitation using zinc ions and urea at low temperature of 90 Degree-Sign C. The powder precipitated resulted in high-purity single-phase ZnO powder when calcined at 280 Degree-Sign C for 3 h in air. The solution pH and the precipitation duration strongly affected the surface area of the calcined ZnO powder. Detailed structural characterizations demonstrated that the synthesized ZnO powder were single crystalline with wurtzite hexagonal phase. The powdered samples precipitated by homogeneous precipitation crystallized directly to hydrozincite without any intermediate phase formation. The phase structures, morphologies and properties of the final ZnO powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering particle size analysis (DLS), and nitrogen physisorption in order to determine the specific surface area (BET) and the pore size distribution (BJH).

  14. Partial substitution of Mo{sup 6+} by S{sup 6+} in the fast oxide ion conductor La{sub 2}Mo{sub 2}O{sub 9}: Synthesis, structure and sulfur depletion

    SciTech Connect

    Mhadhbi, Noureddine [LUNAM Universite, Universite du Maine, CNRS UMR 6283, Institut des Molecules et des Materiaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Corbel, Gwenaeel, E-mail: gwenael.corbel@univ-lemans.fr [LUNAM Universite, Universite du Maine, CNRS UMR 6283, Institut des Molecules et des Materiaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France); Lacorre, Philippe; Bulou, Alain [LUNAM Universite, Universite du Maine, CNRS UMR 6283, Institut des Molecules et des Materiaux du Mans, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9 (France)

    2012-06-15

    Powder-solid state reaction route using La{sub 2}(SO{sub 4}){sub 3} as sulfur source was used to prepare compositions of the solid solution La{sub 2}Mo{sub 2-y}S{sub y}O{sub 9}. Single phases were only obtained in the substitution range extending up to y=0.8 (40 mol% S) at the annealing temperature of 850 Degree-Sign C with regard to the limit of stability of the lanthanum sulphate reactant. Within the synthesis conditions, a stabilization of the high temperature {beta}-form is observed from and above y=0.1 (5 mol% S). Temperature-controlled X-ray diffraction and thermogravimetric analyses have shown that La{sub 2}Mo{sub 2-y}S{sub y}O{sub 9} raw powders undergo thermal decompositions in two steps. Heating above 900 Degree-Sign C, a sulfur depletion to the benefit of molybdenum in La{sub 2}Mo{sub 2-y}S{sub y}O{sub 9} raw powders leads to the formation of La{sub 2}SO{sub 6}. At higher temperature, the exsolved La{sub 2}SO{sub 6} phase then decomposes into La{sub 2}O{sub 3}, which in turn reacts with the sulfur-depleted La{sub 2}Mo{sub 2}O{sub 9} phase to form La{sub 2}MoO{sub 6}. The present study also reveals that depending on the substitution rate y, the sulfur depletion can be induced by ball-milling of raw powders. Along the La{sub 2}Mo{sub 2-y}S{sub y}O{sub 9} series, the isovalent substitution of molybdenum by sulfur tends to restrict in magnitude, or even to suppress above 400 Degree-Sign C, the distortive thermal expansion of the cubic {beta}-type structure, thus strongly decreasing the conductance at high temperature. - Graphical abstract: La{sub 2}O{sub 3}-MoO{sub 3}-'SO{sub 3}' ternary phase diagram showing the exsolution path at low temperature (white arrows) and the total decomposition path at high temperature (black arrows) of {beta}-La{sub 2}Mo{sub 2-y}S{sub y}O{sub 9} raw powders. Highlights: Black-Right-Pointing-Pointer Isovalent substitution of molybdenum by sulfur in La{sub 2}Mo{sub 2}O{sub 9} up to 40 mol%. Black-Right-Pointing-Pointer Stabilization of the {beta}-form for a sulfur content greater than or equal to 5 mol%. Black-Right-Pointing-Pointer Decomposition by sulfur exsolution induced by thermal treatment or ball-milling. Black-Right-Pointing-Pointer Reduction or even cancellation of the distortive thermal expansion above 400 Degree-Sign C. Black-Right-Pointing-Pointer Decrease of conductance at high T involved by the low thermal expansion above 400 Degree-Sign C.

  15. Fabricating solid carbon porous electrodes from powders

    DOEpatents

    Kaschmitter, J.L.; Tran, T.D.; Feikert, J.H.; Mayer, S.T.

    1997-06-10

    Fabrication is described for conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive deionization, and waste treatment. Electrodes fabricated from low surface area (<50 m{sup 2}/gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon composites with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to high surface area carbons, fuel cell electrodes can be produced. 1 fig.

  16. No Substitute for Quality.

    ERIC Educational Resources Information Center

    Russo, Alexander

    2001-01-01

    School leaders are trying pay incentives, consortia, and temp firms to assuage their need for qualified substitute teachers. Five coping strategies include making the job more attractive, increasing the candidate pool, hiring some permanent subs, using automated calling systems, and examining systemic issues. Substitutes are unionizing in some

  17. Iowa Powder Atomization Technologies

    SciTech Connect

    None

    2012-01-01

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  18. Powder towpreg process development

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.; Marchello, Joseph M.

    1991-01-01

    The process for dry powder impregnation of carbon fiber tows being developed at LaRC overcomes many of the difficulties associated with melt, solution, and slurry prepregging. In the process, fluidized powder is deposited on spread tow bundles and fused to the fibers by radiant heating. Impregnated tows have been produced for preform, weaving, and composite materials applications. Design and operating data correlations were developed for scale up of the process to commercial operation. Bench scale single tow experiments at tow speeds up to 50 cm/sec have demonstrated that the process can be controlled to produce weavable towpreg. Samples were woven and molded into preform material of good quality.

  19. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721...naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance...naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is...

  20. Powder Cores s Molypermalloy

    E-print Network

    Software q Current Transformer Design Software q Inductor Design Software q Mag Amp Design Software POWDER.mag-inc.com PRODUCT LITERATURE AND DESIGN SOFTWARE CD CONTAINS q All Product Literature q Common Mode FIlter Design the Proper Core for Saturating Transformers q TWC-S3 Inverter Transformer Core Design and Material Selection

  1. Demystifying Mystery Powders.

    ERIC Educational Resources Information Center

    Kotar, Michael

    1989-01-01

    Describes science activities which use simple chemical tests to distinguish between materials and to determine some of their properties. Explains the water, iodine, heat, acid, baking soda, acid/base indicator, glucose, and sugar tests. Includes activities to enhance chemical testing and a list of suggested powders for use. (RT)

  2. Specific surface area and chemical reactivity of quartz powders during mechanical processing

    SciTech Connect

    Meloni, Paola [Dipartimento di Ingegneria Chimica e Materiali, Universita degli Studi di Cagliari, piazza d'Armi, I-09123 Cagliari (Italy) [Dipartimento di Ingegneria Chimica e Materiali, Universita degli Studi di Cagliari, piazza d'Armi, I-09123 Cagliari (Italy); Laboratorio per lo studio dei Materiali 'Colle di Bonaria', Universita degli Studi di Cagliari, via Ravenna, I-09100 Cagliari (Italy); Carcangiu, Gianfranco [Laboratorio per lo studio dei Materiali 'Colle di Bonaria', Universita degli Studi di Cagliari, via Ravenna, I-09100 Cagliari (Italy) [Laboratorio per lo studio dei Materiali 'Colle di Bonaria', Universita degli Studi di Cagliari, via Ravenna, I-09100 Cagliari (Italy); Istituto di Geologia Ambientale e Geoingegneria (IGAG), CNR, piazza d'Armi, I-09123 Cagliari (Italy); Delogu, Francesco, E-mail: delogu@dicm.unica.it [Dipartimento di Ingegneria Chimica e Materiali, Universita degli Studi di Cagliari, piazza d'Armi, I-09123 Cagliari (Italy)] [Dipartimento di Ingegneria Chimica e Materiali, Universita degli Studi di Cagliari, piazza d'Armi, I-09123 Cagliari (Italy)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Quartz powders were submitted to mechanical processing. Black-Right-Pointing-Pointer The specific surface area and the chemical reactivity increased. Black-Right-Pointing-Pointer A model was developed to describe the observed processes. Black-Right-Pointing-Pointer The amount of powder processed at impact was estimated. Black-Right-Pointing-Pointer The surface density of reactive centers was also estimated by using a test reaction. -- Abstract: The present work focuses on the specific surface area increase, and on the related chemical reactivity enhancement of quartz powders submitted to mechanical processing. The mechanical treatment was carried out in a suitably developed ball mill allowing the control of the frequency and energy of the impacts between ball and reactor. The specific surface area was directly measured by nitrogen physisorption, whereas electron microscopy was used to determine the size distribution of powder particles. Based on the experimental results, a simplified mathematical model was developed to describe the process of specific surface area increase on a phenomenological basis. The model permits to gain valuable information on the amount of powder processed in individual impacts. The density of reactive centers at the surface of powder particles was also estimated by using the neutralization of a free radical as a test reaction. It is shown that the surface density of reactive centers increases with the energy of collisions.

  3. In situ synthesis of magnesium-substituted biphasic calcium phosphate and in vitro biodegradation

    SciTech Connect

    Kim, Tae-Wan; Lee, Hyeong-Shin; Kim, Dong-Hyun; Jin, Hyeong-Ho [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)] [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Hwang, Kyu-Hong [School of Nano and Advanced Materials, Gyeongsang National University, Jinju, Kyungnam 660-701 (Korea, Republic of)] [School of Nano and Advanced Materials, Gyeongsang National University, Jinju, Kyungnam 660-701 (Korea, Republic of); Lee, Jong Kook [Department of Advanced Materials Engineering, Chosun University, Gwangju 501-759 (Korea, Republic of)] [Department of Advanced Materials Engineering, Chosun University, Gwangju 501-759 (Korea, Republic of); Park, Hong-Chae [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)] [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Yoon, Seog-Young, E-mail: syy3@pusan.ac.kr [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)] [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2012-09-15

    Highlights: ? MgBCP were successfully prepared through in situ aqueous co-precipitation method. ? The amount of ?-TCP phase was changed with the magnesium substitution level. ? The substitution of magnesium led to a decrease in the unit cell volume. ? MgBCP could be able to develop a new apatite phase on the surface faster than BCP. -- Abstract: In situ preparation of magnesium (Mg) substituted biphasic calcium phosphate (BCP) of hydroxyapatite (HAp)/?-tricalcium phosphate (?-TCP) were carried out through aqueous co-precipitation method. The concentrations of added magnesium were varied with the calcium in order to obtain constant (Ca + Mg)/P ratios of 1.602. X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) spectroscopy were used to characterize the structure of synthesized magnesium substituted BCP powders. The results have shown that substitution of magnesium in the calcium deficient apatites revealed the formation of biphasic mixtures of different HAp/?-TCP ratios after heating at 1000 C. The ratios of the formation of phase mixtures were dependent on the content of magnesium. After immersing in Hanks balanced salt solution (HBSS) for 1 week, 1 wt% magnesium substituted BCP powders were degraded and precipitation started to be formed with small granules consisting of number of flake-like crystal onto the surface of synthesized powders. On the other hand, in the case of pure BCP powders, the formation of new precipitates was detected after immersion in HBSS for 2 weeks. On the basis of these results, magnesium substituted BCP could be able to develop a new apatite phase on the surface in contact with physiological fluids faster than BCP does. In addition, the retention time to produce the new apatite phase in implantation operation for the BCP powder could be controlled by the amount of magnesium substitution.

  4. The effects of nucleotide substitution on amino acid substitution

    SciTech Connect

    Tumanyan, V.G.; Yakovleva, S.V.; Krovatsky, Yu.V.; Esipova, N.G. [Russian Academy of Sciences, Moscow (Russian Federation). Engelhardt Inst. of Molecular Biology

    1993-12-31

    The aim of the work consists of modeling Dayhoff matrix from the experimentally estimated matrix of nucleotide substitutions. The close resemblance observed between the Dayhoff matrix and the modeling matrix suggests that frequencies of transitions and transversions in genome determine the frequencies of amino acids substitutions. The substitutions apparently are not a consequence of selection of interchangeable amino acids substitutions.

  5. Powder characteristics and coating conditions of fresh and reused polyester resins for electrostatic powder coating: powder recycling and loss prevention

    Microsoft Academic Search

    A. W. Lothongkum; R. Nonthapone; K. Seangkiatiyuth; W. Tanthapanichkoon

    2007-01-01

    Powder characteristics and coating conditions are significant factors in electrostatic powder coating. In this work, powder characteristics of the reused polyester resin or recycled powder particles in terms of shape, size, particle size distribution, moisture content, density, flowability, fluidity and chargeability were compared with those of fresh resin or as-received powder to consider powder recycling. The coating conditions for a

  6. Processing polymeric powders

    NASA Technical Reports Server (NTRS)

    Throne, James L.

    1989-01-01

    The concept of uniformly and continuously depositing and sinter-fusing nominal 0.1 to 40 microns dimensioned electrostatically charged polymer powder particles onto essentially uniformly spread 5 to 20 micron grounded continuous fiber tow to produce a respoolable thermoplastic composite two-preg was formulated at NASA Langley. The process was reduced to practice under a NASA grant at the University of Akron this spring. The production of tow-preg is called phase 1. The production of ultrafine polymer powders from 5 to 10 percent (wt) polymer solids in solvent is considered. This is phase 0 and is discussed. The production of unitape from multi tow-pregs was also considered. This is phase 2 and is also discussed. And another approach to phase 1, also proposed last summer, was scoped. This is phase 1A and is also discussed.

  7. Magnetic and Magnetoelastic Properties of Chromium Substituted Cobalt Ferrite

    Microsoft Academic Search

    C. Lo; P. Matlage; Y. Melikhov; J. Snyder; S. Song; D. Jiles

    2006-01-01

    In the present study, A series of polycrystalline chromium-substituted cobalt ferrite samples with compositions of CoCrxFe2-xO4 were prepared by standard powder ceramic techniques. The microstructure and final composition of the samples were characterized using a scanning electron microscope with energy-dispersive X-ray spectroscopy (EDX). The crystal structure of the samples was determined by X-ray diffractometry to be cubic spinel. Curie temperature,

  8. Magnetic properties of aerosol synthesized Co-substituted spinel ferrites

    Microsoft Academic Search

    W. A. Kaczmarek; A. Calka; B. W. Ninham

    1993-01-01

    An aerosol technique and pyrolysis of a mixture of cobalt-nickel-zinc-magnesium and iron nitrates with a fixed stoichiometric composition are used to prepare submicron spherical particles of Co substituted ferrite powders with a spinel-type structure. The magnetic properties are studied using vibrating sample magnetometry (VSM) and ferrimagnetic resonance (FMR). Important parameters such as saturation magnetization, FMR linewidth, and spectroscopic splitting factor

  9. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false Substituted phenyl azo substituted sulfocarbopolycle, sodium...Substances 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium...identified generically as a substituted phenyl azo substituted...

  10. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 false Substituted phenyl azo substituted sulfocarbopolycle, sodium...Substances 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium...identified generically as a substituted phenyl azo substituted...

  11. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false Substituted phenyl azo substituted benzenediazonium salt...Substances 721.1555 Substituted phenyl azo substituted benzenediazonium salt...identified generically as a substituted phenyl azo substituted benzenediazonium...

  12. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false Substituted phenyl azo substituted sulfocarbopolycle, sodium...Substances 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium...identified generically as a substituted phenyl azo substituted...

  13. 40 CFR 721.2122 - Substituted phenyl azo substituted sulfo carbopolycycle.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Substituted phenyl azo substituted sulfo carbopolycycle...Substances 721.2122 Substituted phenyl azo substituted sulfo carbopolycycle...identified generically as a substituted phenyl azo substituted sulfo...

  14. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2012-07-01 false Substituted phenyl azo substituted benzenediazonium salt...Substances 721.1555 Substituted phenyl azo substituted benzenediazonium salt...identified generically as a substituted phenyl azo substituted benzenediazonium...

  15. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false Substituted phenyl azo substituted sulfocarbopolycle, sodium...Substances 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium...identified generically as a substituted phenyl azo substituted...

  16. Fluidised powder as a new target technology

    E-print Network

    McDonald, Kirk

    : scope for a rig #12;Powder jet test plant layout Compressed air supplyVacuum/air powder #12;Powder jet/w solid to air ratio is not good enough!) How does a dense, dense powder jet behave like? Preliminary tests at Gericke ltd #12;AIR/PRESSURE IN POWDER IN JET GENERATION AIR EXTRACTION POWDER OUT DENSE

  17. Hydrothermal synthesis and low temperature conduction properties of substituted ceria ceramics

    Microsoft Academic Search

    Kimihiro Yamashita; K. V. Ramanujachary; Martha Greenblatt

    1995-01-01

    Rare earth or alkaline earth oxide-substituted ceria (CeO2) powders were successfully prepared via hydrothermal synthetic route. Using these powders after freeze-drying, highly dense ceramics of Ce1?xMxO2 with M = Ca2+, Sr2+, Sm3+, Gd3+ and Y3+ and x = 0.2 were prepared by sintering at much lower temperatures than 1700 C, common for CeO2 preparation by conventional ceramic techniques. For example,

  18. Infrared studies of apatites. I. Vibrational assignments for calcium, strontium, and barium hydroxyapatities utilizing isotopic substitution

    Microsoft Academic Search

    B. O. Fowler

    1974-01-01

    The infrared spectra of powdered calcium hydroxyapatite isotopically ; substituted with D, ¹⁸O, ⁴⁴Ca, and ⁴⁸Ca and infrared spectra of ; powdered strontium and barium hydroxyapatites and their deuterated analogs are ; reported at 48 and - 185 deg in the 4000-200cm-¹ region. Band ; assignments, based on isotopic frequency shifts, band intensity, band temperature ; dependency, and comparisons between

  19. Chemical reactions of metal powders with organic and inorganic liquids during ball milling

    NASA Technical Reports Server (NTRS)

    Arias, A.

    1975-01-01

    Chromium and/or nickel powders were milled in metal chlorides and in organic liquids representative of various functional groups. The powders always reacted with the liquid and became contaminated with elements from them. The milled powders had specific surface areas ranging from 0.14 to 37 sq m/g, and the total contamination with elements from the milling liquid ranged from 0.01 to 56 weight percent. Compounds resulting from substitution, addition, or elimination reactions formed in or from the milling liquid.

  20. Effect of the carbon addition to filling powder ball-milled with oils on the critical current density in ex situ processed MgB2 tapes

    Microsoft Academic Search

    H Fujii; K Ozawa; H Kitaguchi

    2012-01-01

    We have studied the effect of planetary ball-milling of filling powder with mineral and silicon oils on the carbon substitution in MgB2 and the critical current density (Jc) of Fe-sheathed MgB2 tapes fabricated through an ex situ process in a powder-in-tube (PIT) technique. The mineral oil is much more effective for the carbon substitution and hence the Jc enhancement of

  1. Sintering of powder mixtures and the growth of ferrous powder metallurgy

    Microsoft Academic Search

    K. S Narasimhan

    2001-01-01

    Advances in the understanding of sintering of powder mixtures contributed significantly to the growth of ferrous powder metallurgy industry. Solid-state sintering and liquid-phase activated sintering play an important role in the sintering of powder mixtures. In this paper, sintering of iron powder with graphite; iron powder with copper and graphite; iron powder with nickel and graphite; iron powder with phosphorus;

  2. Currency Substitution in Russia

    Microsoft Academic Search

    Fridman Alla; Verbetsky Aleksey

    2001-01-01

    Due to high inflation and the lack of financial instruments, the Russian economy is currently highly dollarized. The share of dollars in the total amount of cash circulating in the Russian economy constitutes about 80%. What is the degree of this currency substitution phenomenon? What are the implications of dollarization for the possibility of inflationary financing of the budget deficit

  3. The Age of Substitutability

    ERIC Educational Resources Information Center

    Goeller, H. E.; Weinberg, Alvin M.

    1976-01-01

    Dwindling mineral resources might cause a shift from nonrenewable resources to renewable resources and inexhaustible elements such as iron and aluminum. Alternative energy sources such as breeder, fusion, solar, and geothermal power must be developed for production and recycling of materials. Substitution and, hence, living standards ultimately

  4. Effects of Zr substitution for rare earth on the thermal stability of melt-spun (Nd0.75Pr0.25)12.5-xZrxFe82B5.5 (x=0-3) powder and magnets

    Microsoft Academic Search

    Z. Chen; B. R. Smith; B. M. Ma

    2002-01-01

    Summary form only given. Early studies have shown that Zr goes into the 2:14:1 structure and replaces the rare earth atoms, and leads to an increase in the anisotropy field in R2Fe14B (R=Ce, Nd, Pr, Gd and Dy). This raises an interesting question: can Zr substitution improve the performance of R2Fe14B type magnets and reduce the raw material cost? Thus,

  5. Comminution of stainless steel powders

    Microsoft Academic Search

    B. A. Borok; R. P. Schchegoleva; L. S. Golubeva; F. S. Sariadi; E. M. Rabinovich

    1974-01-01

    1.Atmospheric milling in barrel type mixers at a powder-to-ball weight ratio of 1::2 is an effective means of comminuting stainless steel powders produced by the coreduction process. In the work described, milling for 27 h was found to increase the amount of the -0.063-mm fraction from ~15 to ~75% for a Kh18N15 steel powder and from ~24.6 to ~70%for a

  6. Design of Tools for Stamping in Reactive Powder Concrete for Thin Sheets

    Microsoft Academic Search

    Ahmed Tafraoui; Soltane Lebaili

    2006-01-01

    We proposed to produce tools for stamping out of reactive powder concrete which substitutes the resin concrete tools covered with a resin with cast (freezing-coat) for the prototype parts (< 100 parts), in order to decrease the deadlines, to simplify the manufacturing process and to reduce the costs in the automobile body. A bench of abrasive wear was developed to

  7. Skin substitutes: An Indian perspective

    PubMed Central

    Singh, A. K.; Shenoy, Y. R.

    2012-01-01

    There have been numerous alternatives developed to replace skin. These can either be permanent substitutes or temporary substitutes, which need to be replaced later by autologous grafts. These have been tried in recent times as an attempt to reduce the need or in the case of permanent substitutes ,altogether replace autologous skin grafts. However till date no ideal skin substitute has been developed. Various factors have to be considered while choosing one of these substitutes. In a developing country like India awareness and availability of these skin substitutes is not adequate considering the volume of cases that require this modality of treatment. Also there are skin substitutes developed in our country that need to be highlighted. This article is an attempt to review the vast array of skin substitutes that have been developed and consider their utility and feasibility for developing countries. PMID:23162239

  8. The Substitution of a Super Black Fixed Micro-Object for an Optical Microcavity in a Delayed Choice Experiment to Send Information Immediately Between 2 Paired Particles: Simplifying the Experiment

    NASA Astrophysics Data System (ADS)

    Snyder, Douglas

    2015-04-01

    An experiment has been described that relies on a delayed choice for an idler photon that immediately affects the signal photon with which it is at least initially entangled and for which the idler photon provides which-way information. The delayed choice concerns whether to maintain or eliminate the entanglement before any measurements are made. In one option of the delayed choice, the entanglement can be eliminated because the relevant state of the idler photon related to its entanglement is eliminated when the idler photon enters an optical microcavity filled with photons with the same mode as the incoming idler photon. The microcavity is located at the crossroads of two possible idler photon paths. The relevant state of the idler photon characterizes the particular path taken by the photon and this information is eliminated when the particle enters the cavity. Over a number of runs with this choice, the distribution of the paired signal photons shows interference. If the entanglement is maintained, the distribution of the paired signal photons shows which-way information. This experiment can be simplified by using a super black material (e.g., Vantablack) affixed to a fixed micro-object located at the crossroads of the two possible idler photon paths instead of the optical microcavity. The photon would be absorbed by the material and there would be no way to detect from which direction it came. Objects such as fixed mirrors in a Mach Zehnder interferometer do not provide ww information. The super black fixed micro-object should not either.

  9. Exfoliation and thermal transformations of Nb-substituted layered titanates

    SciTech Connect

    Song Haiyan; Sjastad, Anja O.; Fjellvag, Helmer; Okamoto, Hiroshi [Department of Chemistry and Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo (Norway); Vistad, Ornulv B.; Arstad, Bjornar [SINTEF Materials and Chemistry, P.O. Box 124, Blindern, N-0314 Oslo (Norway); Norby, Poul, E-mail: pnor@risoe.dtu.dk [Department of Chemistry and Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo (Norway); Materials Research Division, Riso National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, DK-4000 Roskilde (Denmark)

    2011-12-15

    Single-layer Nb-substituted titanate nanosheets of ca. 1 nm thickness were obtained by exfoliating tetrabutylammonium (TBA)-intercalated Nb-substituted titanates in water. AFM images and turbidity measurements reveal that the exfoliated nanosheets crack and corrugate when sonicated. Upon heating, the thermal transformation into anatase and further to rutile is retarded. This suppression of the phase transition upon higher valent substitution may promote technological applications of anatase thin films, hereunder development of films with TCO properties. Depending on the oxygen partial pressure during the transformation, the Nb-substitution into TiO{sub 2} provokes different defect situations and also electronic properties. At reducing conditions, Nb is incorporated as Nb{sup V} and an equivalent amount of Ti{sup IV} is transformed to Ti{sup III} as evidenced by XPS. Magnetic susceptibility data show accordingly paramagnetic behavior. For samples heated in air Ti{sup IV} and Nb{sup V} cations prevail, the latter is compensated by cation vacancies. {sup 93}Nb MAS NMR data prove that Nb is finely dispersed into the transformed (Ti,Nb)O{sub 2} oxide matrices without sign of Nb{sub 2}O{sub 5} (nano)precipitates. The Nb-O-Ti bonds and defects at cation sites are considered key factors for increasing the transformation temperatures for conversion of the nanosheets to anatase and finally into rutile. It is further tempting to link the delay in crystallization to morphology limitations originating from the nanosheets. The present work shows that layered Nb-titanates are appropriate precursors for formation of highly oriented Nb-substituted anatase thin films via delamination, reconstruction and subsequent heat treatment. - Graphical abstract: Layered Nb-titanates are appropriate precursors for formation of highly oriented Nb-substituted anatase thin films via delamination, reconstruction and subsequent heat treatment. Highlights: Black-Right-Pointing-Pointer Single layer Nb-substituted nanosheets were obtained by exfoliation of layered titanates. Black-Right-Pointing-Pointer Nb(V) successfully introduced into anatase and rutile solid solutions. Black-Right-Pointing-Pointer Anatase obtained from reconstructed nanosheets exhibit enhanced thermal stability. Black-Right-Pointing-Pointer Oxygen partial pressure influences the valence of Nb in heat-treated samples. Black-Right-Pointing-Pointer Deposition of oriented thin Ti(Nb)O{sub 2} layers by spray coating was demonstrated.

  10. Synthesis of beta silicon carbide powders using carbon coated fumed silica

    Microsoft Academic Search

    Rasit Koc; Sai V. Cattamanchi

    1998-01-01

    The synthesis of beta silicon carbide (-SiC) powders by carbothermic reduction of carbon coated silica and silica mixed with carbon black was investigated. The production of -SiC powders by using carbon coated silica consists of two steps. The first step is to prepare the carbon coated silica precursor by coating fumed silica particles with carbon by pyrolytic cracking of a

  11. Nanoliposomal Dry Powder Formulations

    PubMed Central

    Patel, Gaurang; Chougule, Mahavir; Singh, Mandip; Misra, Ambikanandan

    2013-01-01

    Liposomal dry powder formulations (DPFs) have proven their superiority over conventional DPFs due to favorably improved pharmacokinetics and pharmacodynamics of entrapped drugs, and thus, reduced local and systemic toxicities. Nanoliposomal DPFs (NLDPFs) provide stable, high aerosolization efficiency to deep lung, prolonged drug release, slow systemic dilution, and avoid macrophage uptake of encapsulated drug by carrier-based delivery of nano-range liposomes. This chapter describes methods of preparation of nanoliposomes (NLs) and NLDPFs, using various techniques, and their characterization with respect to size distribution, flow behavior, in vitro drug release profile, lung deposition, cellular uptake and cytotoxicity, and in vivo pharmacokinetics and pharmacodynamics. Some examples have been detailed for better understanding of the methods of preparation and evaluation of NLDPFs by investigators. PMID:19903555

  12. Melamine milk powder and infant formula sold in East Africa.

    PubMed

    Schoder, Dagmar

    2010-09-01

    This is the first study proving the existence of melamine in milk powder and infant formula exported to the African market. A total of 49 milk powder batches were collected in Dar-es-Salaam (Tanzania, East Africa), the center of international trade in East Africa, which serves as a commercial bottleneck and shipment hub for sub-Saharan, Central, and East Africa. Two categories of samples were collected between October and December 2008, immediately after the melamine contamination of Chinese products became public: (i) market brands of all international companies supplying the East African market and (ii) illegally sold products from informal channels. Melamine concentration was determined with the AgraQuant Melamine Sensitive Assay. Despite the national import prohibition of Chinese milk products and unlabeled milk powder in Tanzania, 11% (22 of 200) of inspected microretailers sold milk powder on the local black market. Manufacturers could be identified for only 55% (27) of the 49 investigated batches. Six percent (3 of 49) of all samples and 11% (3 of 27) of all international brand name products tested revealed melamine concentrations up to 5.5 mg/kg of milk powder. This amount represents about twice the tolerable daily intake as suggested by the U.S Food and Drug Administration. Based on our study, we can assume that the number of affected children in Africa is substantial. PMID:20828481

  13. Mound powder loader, Mod 1

    SciTech Connect

    Gress, A.V. Jr.

    1985-08-21

    At the investigation of Sandia Albuquerque, a semiautomatic powder loader was designed and fabricated for pyrotechnics devices. The basic functions of the system were to load a precise, measured amount of powder into a charge holder and to compact the mixture to a specified density. This report documents the history, rationale, design, and performance of the Mod 1 loader.

  14. Black Saturn

    E-print Network

    Henriette Elvang; Pau Figueras

    2007-04-03

    Using the inverse scattering method we construct an exact stationary asymptotically flat 4+1-dimensional vacuum solution describing Black Saturn: a spherical black hole surrounded by a black ring. Angular momentum keeps the configuration in equilibrium. Black saturn reveals a number of interesting gravitational phenomena: (1) The balanced solution exhibits 2-fold continuous non-uniqueness for fixed mass and angular momentum; (2) Remarkably, the 4+1d Schwarzschild black hole is not unique, since the black ring and black hole of black saturn can counter-rotate to give zero total angular momentum at infinity, while maintaining balance; (3) The system cleanly demonstrates rotational frame-dragging when a black hole with vanishing Komar angular momentum is rotating as the black ring drags the surrounding spacetime. Possible generalizations include multiple rings of saturn as well as doubly spinning black saturn configurations.

  15. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  16. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  17. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  18. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  19. 21 CFR 73.2647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Copper powder. 73.2647 Section 73...CERTIFICATION Cosmetics 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity...

  20. Synthesis of boron nitride powders

    NASA Astrophysics Data System (ADS)

    Dreissig, Dirk Horst

    2002-09-01

    In the materials science community there is much interest in the development of new, efficient approaches for preparing ceramic powders having properties or performance characteristics not found with powders produced by traditional metallurgical synthesis methods. In this regard, aerosol-based syntheses are finding general acceptance for the preparation of non-metal and metal oxide powders. In contrast, much less effort has been given to aerosol-type syntheses for non-oxide powders despite potentially useful benefits. This dissertation describes the application of two chemical systems in aerosol assisted vapor phase synthesis (AAVS) for the preparation of spherical morphology boron oxynitride, BNxOy, powders that are subsequently converted to spherical morphology boron nitride in a second nitridation step. Chapter 1 describes the AAVS synthesis of BNxOy powders using a reaction of an aqueous boric acid containing aerosol with ammonia at 1000C. The effect of reactor tube material, total gas flow rate, ammonia concentration, boric acid concentration, and urea addition to the boric acid aerosol on the percent oxygen composition is described. The resulting BNxOy powders contain significant amounts of oxygen that require replacement in a second stage nitridation reaction at elevated temperature under ammonia. The influences of the reaction temperature profile, crucible geometry and transformation additive on final oxygen composition and powder crystallinity are described. Chapter 2 outlines the formation of BNxOy powders from an AAVS reaction between the boron precursor (MeO)3B and ammonia. The formation of the powders is studied as a function of total gas flow rate and ammonia concentration. In all cases the resulting powders contain lower levels of oxygen compared to powders produced from aqueous boric acid aerosols. The conversion of the BNxOy powders in the second stage nitridation reaction with ammonia is examined as a function of crucible geometry, temperature profile and ammonia flow rate. In support of this process, the molecular reaction between (MeO)3B and NH3 was reexamined. The adduct, (MeO)3BNH3, was isolated and its molecular structure determined by single crystal X-ray diffraction techniques. The results of these studies provide guidance for more detailed studies that should result in industrial scale synthesis of spherical morphology BN which currently is not formed by standard metallurgical syntheses. This new material has potential applications in several areas including the formation of BN loaded organic polymer composites.

  1. Synthesis, structure, thermal stability, mechanical and antibacterial behaviour of lanthanum (La?) substitutions in ?-tricalciumphosphate.

    PubMed

    Meenambal, Rugmani; Singh, Ram Kishore; Nandha Kumar, P; Kannan, S

    2014-10-01

    Five different concentrations of lanthanum (La(3+)) substituted ?-tricalcium phosphate [?-TCP, ?-Ca3(PO4)2] were formed through aqueous precipitation technique and the results were compared with stoichiometric ?-TCP. All the La(3+) substituted ?-TCP powders were characterized using XRD, FT-IR, XRF, Raman spectroscopy and Rietveld refinement of the XRD data. The results from the investigation confirmed the presence of La(3+) in rhombohedral ?-TCP structure. The substitution of higher sized of La(3+) led to the considerable enhancement in lattice parameters of ?-TCP crystal structure and La(3+) was found to have occupied the eight fold coordinated Ca (3) site of ?-TCP structure. La(3+) occupancy at the Ca (3) site resulted in the significant distortions of the associated PO4 tetrahedra, which were supported by the Raman and FT-IR spectroscopic techniques. La(3+) presence in the crystal lattice of ?-TCP also led to the delay in allotropic phase transformation of ?-TCP to ?-TCP till 1300C, thus signifying the good thermal stability of La(3+) substituted ?-TCP powders. The antibacterial efficiency of La(3+) substituted ?-TCP powders was confirmed from the in vitro tests done on microbes such as Staphylococcus aureus and Escheria coli. Further, the presence of La(3+) in the crystal lattice of ?-TCP did not affect the hardness and Young's modulus values of ?-TCP. PMID:25175254

  2. New Bismuth-Substituted Hydroxyapatite Nanoparticles for Bone Tissue Engineering

    NASA Astrophysics Data System (ADS)

    Ciobanu, Gabriela; Bargan, Ana Maria; Luca, Constantin

    2015-06-01

    New bismuth-substituted hydroxyapatite [Ca10-x Bi x (PO4)6(OH)2 where x = 0-2.5] nanoparticles were synthesized by the co-precipitation method from aqueous solutions. The structural properties of the samples were analyzed by scanning electron microscopy coupled with x-ray analysis, x-ray powder diffraction, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller surface area analysis. The results confirm that bismuth ions have been incorporated into the hydroxyapatite lattice. The prepared nanocrystalline powders consisted of hydroxyapatite as single phase with hexagonal structure, crystal sizes smaller than 60 nm and (Bi + Ca)/P atomic ratio of around 1.67. The hydroxyapatite samples doped with Bi have mesoporous textures with pores size of around 2 nm and specific surface area in the range of 12-25 m2/g. The Bi-substituted hydroxyapatite powders are more effective against Gram-negative Escherichia coli bacteria than Gram-positive Staphylococcus aureus bacteria.

  3. Silica powders for powder evacuated thermal insulating panel and method

    DOEpatents

    Harris, M.T.; Basaran, O.A.; Kollie, T.G.; Weaver, F.J.

    1996-01-02

    A powder evacuated thermal insulating panel using generally spherical and porous silica particles of a median size less than about 100 nanometers in diameter, a pour packing density of about 0.4 to 0.6 g/cm{sup 3} and an external surface area in the range of about 90 to 600 m{sup 2}/g is described. The silica powders are prepared by reacting a tetraalkyl silicate with ammonia and water in an alcohol solvent, distilling the solution after the reaction to remove the ammonia and recover the alcohol. The resulting aqueous slurry was dried, ball-milled, and dried again to provide the silica particles with defined internal and external porosity. The nanometer size and the large external surface area of the silica particles along with the internal and external porosity of the silica particles provide powder evacuated thermal insulating panels with significantly higher R-values than obtainable using previously known silica powders. 2 figs.

  4. Method for molding ceramic powders

    DOEpatents

    Janney, M.A.

    1990-01-16

    A method for molding ceramic powders comprises forming a slurry mixture including ceramic powder, a dispersant for the metal-containing powder, and a monomer solution. The monomer solution includes at least one multifunctional monomer, a free-radical initiator, and an organic solvent. The slurry mixture is transferred to a mold, and the mold containing the slurry mixture is heated to polymerize and crosslink the monomer and form a firm polymer-solvent gel matrix. The solid product may be removed from the mold and heated to first remove the solvent and subsequently remove the polymer, where after the product may be sintered.

  5. Polyimides comprising substituted benzidines

    NASA Technical Reports Server (NTRS)

    Harris, Frank W. (Inventor)

    1991-01-01

    A new class of polyimides and copolyimides made from substituted benzidines and aromatic dianhydrides and other aromatic diamines. The polyimides obtained with said diamines are distinguished by excellent thermal, excellent solubility, excellent electrical properties such as very low dielectric constants, excellent clarity and mechanical properties making the polyimides ideally suited as coating materials for microelectronic apparatii, as membranes for selective molecular or gas separation, as fibers in molecular composites, as high tensile strength, high compression strength fibers, as film castable coatings, or as fabric components.

  6. Black Holes

    NASA Astrophysics Data System (ADS)

    Livio, Mario; Koekemoer, Anton M.

    2011-02-01

    Participants; Preface Mario Livio and Anton Koekemoer; 1. Black holes, entropy, and information G. T. Horowitz; 2. Gravitational waves from black-hole mergers J. G. Baker, W. D. Boggs, J. M. Centrella, B. J. Kelley, S. T. McWilliams and J. R. van Meter; 3. Out-of-this-world physics: black holes at future colliders G. Landsberg; 4. Black holes in globular clusters S. L. W. McMillan; 5. Evolution of massive black holes M. Volonteri; 6. Supermassive black holes in deep multiwavelength surveys C. M. Urry and E. Treister; 7. Black-hole masses from reverberation mapping B. M. Peterson and M. C. Bentz; 8. Black-hole masses from gas dynamics F. D. Macchetto; 9. Evolution of supermassive black holes A. Mller and G. Hasinger; 10. Black-hole masses of distant quasars M. Vestergaard; 11. The accretion history of supermassive black holes K. Brand and the NDWFS Botes Survey Teams; 12. Strong field gravity and spin of black holes from broad iron lines A. C. Fabian; 13. Birth of massive black-hole binaries M. Colpi, M. Dotti, L. Mayer and S. Kazantzidis; 14. Dynamics around supermassive black holes A. Gualandris and D. Merritt; 15. Black-hole formation and growth: simulations in general relativity S. L. Shapiro; 16. Estimating the spins of stellar-mass black holes J. E. McClintock, R. Narayan and R. Shafee; 17. Stellar relaxation processes near the Galactic massive black hole T. Alexander; 18. Tidal disruptions of stars by supermassive black holes S. Gezari; 19. Where to look for radiatively inefficient accretion flows in low-luminosity AGN M. Chiaberge; 20. Making black holes visible: accretion, radiation, and jets J. H. Krolik.

  7. Ceramic powder for sintering materials

    NASA Technical Reports Server (NTRS)

    Akiya, H.; Saito, A.

    1984-01-01

    Surface activity of ceramic powders such as MgO and Al2O3, for use in sintering with sp. emphasis on their particle size, shape, particle size distribution, packing, and coexisting additives and impurities are reviewed.

  8. Luminescence of powdered uranium glasses

    NASA Technical Reports Server (NTRS)

    Eubanks, A. G.; Mcgarrity, J. M.; Silverman, J.

    1974-01-01

    Measurement of cathodoluminescence and photoluminescence efficiencies in powdered borosilicate glasses having different particle size and different uranium content. Excitation with 100 to 350 keV electrons and with 253.7 nm light was found to produce identical absolute radiant exitance spectra in powdered samples. The most efficient glass was one containing 29.4 wt% B2O3, 58.8 wt% SiO2, 9.8 wt% Na2O and 2.0 wt% UO2.

  9. Powder collection apparatus/method

    DOEpatents

    Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA); Moore, Jeffery A. (Ames, IA)

    1994-01-11

    Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally equal to the angle of the housing interior wall measured from the same horizontal plane so as to direct the gas stream into the expansion chamber generally tangent to the housing interior wall to establish a downward swirling gas stream flow in the expansion chamber. A powder collection container is communicated to the outlet of the expansion chamber to collect the powder for further processing.

  10. Powder collection apparatus/method

    DOEpatents

    Anderson, I.E.; Terpstra, R.L.; Moore, J.A.

    1994-01-11

    Device for separating and collecting ultrafine atomized powder from the gas stream of a gas atomizing apparatus comprises a housing having an interior wall oriented at an angle relative to horizontal so as to form a downwardly converging, conical expansion chamber, an inlet conduit communicated to the expansion chamber proximate an upper region thereof for receiving the gas stream, and an outlet proximate a lower region of the expansion chamber. The inlet conduit is oriented at a compound inclined angle (with respect to horizontal) selected to promote separation and collection of powder from the gas stream in the expansion chamber. The compound angle comprises a first entrance angle that is greater than the angle of repose of the powder on the housing interior wall such that any powder accumulation in the inlet conduit tends to flow down the wall toward the outlet. The second angle is selected generally equal to the angle of the housing interior wall measured from the same horizontal plane so as to direct the gas stream into the expansion chamber generally tangent to the housing interior wall to establish a downward swirling gas stream flow in the expansion chamber. A powder collection container is communicated to the outlet of the expansion chamber to collect the powder for further processing. 4 figures.

  11. Rapid hydrothermal flow synthesis and characterisation of carbonate- and silicate-substituted calcium phosphates

    PubMed Central

    Knowles, Jonathan C; Rehman, Ihtesham; Darr, Jawwad A

    2013-01-01

    A range of crystalline and nano-sized carbonate- and silicate-substituted hydroxyapatite has been successfully produced by using continuous hydrothermal flow synthesis technology. Ion-substituted calcium phosphates are better candidates for bone replacement applications (due to improved bioactivity) as compared to phase-pure hydroxyapatite. Urea was used as a carbonate source for synthesising phase pure carbonated hydroxyapatite (CO3-HA) with ?5?wt% substituted carbonate content (sample 7.5CO3-HA) and it was found that a further increase in urea concentration in solution resulted in biphasic mixtures of carbonate-substituted hydroxyapatite and calcium carbonate. Transmission electron microscopy images revealed that the particle size of hydroxyapatite decreased with increasing urea concentration. Energy-dispersive X-ray spectroscopy result revealed a calcium deficient apatite with Ca:P molar ratio of 1.45 (0.04) in sample 7.5CO3-HA. For silicate-substituted hydroxyapatite (SiO4-HA) silicon acetate was used as a silicate ion source. It was observed that a substitution threshold of ?1.1?wt% exists for synthesis of SiO4-HA in the continuous hydrothermal flow synthesis system, which could be due to the decreasing yields with progressive increase in silicon acetate concentration. All the as-precipitated powders (without any additional heat treatments) were analysed using techniques including Transmission electron microscopy, X-ray powder diffraction, Differential scanning calorimetry, Thermogravimetric analysis, Raman spectroscopy and Fourier transform infrared spectroscopy. PMID:22983020

  12. Preparation and characterization of cobalt-substituted anthrax lethal factor

    SciTech Connect

    Saebel, Crystal E.; Carbone, Ryan; Dabous, John R.; Lo, Suet Y. [Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Rd., Sudbury, Ontario, Canada P3E 2C6 (Canada)] [Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Rd., Sudbury, Ontario, Canada P3E 2C6 (Canada); Siemann, Stefan, E-mail: ssiemann@laurentian.ca [Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Rd., Sudbury, Ontario, Canada P3E 2C6 (Canada)] [Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Rd., Sudbury, Ontario, Canada P3E 2C6 (Canada)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Cobalt-substituted anthrax lethal factor (CoLF) is highly active. Black-Right-Pointing-Pointer CoLF can be prepared by bio-assimilation and direct exchange. Black-Right-Pointing-Pointer Lethal factor binds cobalt tightly. Black-Right-Pointing-Pointer The electronic spectrum of CoLF reveals penta-coordination. Black-Right-Pointing-Pointer Interaction of CoLF with thioglycolic acid follows a 2-step mechanism. -- Abstract: Anthrax lethal factor (LF) is a zinc-dependent endopeptidase involved in the cleavage of mitogen-activated protein kinase kinases near their N-termini. The current report concerns the preparation of cobalt-substituted LF (CoLF) and its characterization by electronic spectroscopy. Two strategies to produce CoLF were explored, including (i) a bio-assimilation approach involving the cultivation of LF-expressing Bacillus megaterium cells in the presence of CoCl{sub 2}, and (ii) direct exchange by treatment of zinc-LF with CoCl{sub 2}. Independent of the method employed, the protein was found to contain one Co{sup 2+} per LF molecule, and was shown to be twice as active as its native zinc counterpart. The electronic spectrum of CoLF suggests the Co{sup 2+} ion to be five-coordinate, an observation similar to that reported for other Co{sup 2+}-substituted gluzincins, but distinct from that documented for the crystal structure of native LF. Furthermore, spectroscopic studies following the exposure of CoLF to thioglycolic acid (TGA) revealed a sequential mechanism of metal removal from LF, which likely involves the formation of an enzyme: Co{sup 2+}:TGA ternary complex prior to demetallation of the active site. CoLF reported herein constitutes the first spectroscopic probe of LF's active site, which may be utilized in future studies to gain further insight into the enzyme's mechanism and inhibitor interactions.

  13. Ceramic oxide powders and the formation thereof

    DOEpatents

    Katz, J.L.; Chenghung Hung.

    1993-12-07

    Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions. 14 figures.

  14. Ceramic oxide powders and the formation thereof

    DOEpatents

    Katz, Joseph L. (Baltimore, MD); Hung, Cheng-Hung (Baltimore, MD)

    1993-01-01

    Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions.

  15. Trifluoromethyl-substituted tetrathiafulvalenes

    PubMed Central

    Jeannin, Olivier; Barrire, Frdric

    2015-01-01

    Summary A series of tetrathiafulvalenes functionalized with one or two trifluoromethyl electron-withdrawing groups (EWG) is obtained by phosphite coupling involving CF3-substituted 1,3-dithiole-2-one derivatives. The relative effects of the EWG such as CF3, CO2Me and CN on the TTF core were investigated from a combination of structural, electrochemical, spectrochemical and theoretical investigations. Electrochemical data confirm the good correlations between the first oxidation potential of the TTF derivatives and the ?meta Hammet parameter, thus in the order CO2Me < CF3 < CN, indicating that, in any case, the mesomeric effect of the substituents is limited. Besides, crystal structure determinations show that the deformation of the unsymmetrically substituted dithiole rings, when bearing one, or two different EWG, and attributed to the mesomeric effect of ester or nitrile groups, is not notably modified or counter-balanced by the introduction of a neighboring trifluoromethyl group. DFT calculations confirm these observations and also show that the low energy HOMOLUMO absorption band found in nitrile or ester-substituted TTFs is not found in TTF-CF3, where, as in TTF itself, the low energy absorption band is essentially attributable to a HOMO?LUMO + 1 transition. Despite relatively high oxidation potentials, these donor molecules with CF3 EWG can be involved in charge transfer complexes or cation radical salts, as reported here for the CF3-subsituted EDT-TTF donor molecule. A neutral charge transfer complex with TCNQ, (EDT-TTF-CF3)2(TCNQ) was isolated and characterized through alternated stacks of EDT-TTF-CF3 dimers and TCNQ in the solid state. A radical cation salt of EDT-TTF-CF3 is also obtained upon electrocrystallisation in the presence of the FeCl4 ? anion. In this salt, formulated as (EDT-TTF-CF3)(FeCl4), the (EDT-TTF-CF3)+ radical cations are associated two-by-two into centrosymmetric dyads with a strong pairing of the radical species in a singlet state. PMID:26124867

  16. Synthesis of indium tin oxide (ITO) and fluorine-doped tin oxide (FTO) nano-powder by solgel combustion hybrid method

    Microsoft Academic Search

    Chi-Hwan Han; Sang-Do Han; Jihye Gwak; S. P. Khatkar

    2007-01-01

    ITO and FTO nano-powders were synthesized employing a new route solgel combustion hybrid method using acetylene black as a fuel. The dried gels exhibited an auto-catalytic combustion behavior. ITO and FTO nano-powders with narrow size distribution were obtained at 750C. Crystal structures were examined by powder X-ray diffraction (XRD) and particle morphology as well as crystal size was investigated by

  17. Mssbauer studies for LaCo substituted strontium ferrite

    Microsoft Academic Search

    Dong Hyeok Choi; Sang Won Lee; In-Bo Shim; Chul Sung Kim

    2006-01-01

    LaCo substituted Sr ferrite (LaCo)xSr1?xFe12?xO19 (x=0.00.4) powders synthesized by solgel process were investigated for their magnetic properties. The crystalline structures were characterized by X-ray diffractometer (XRD), and magnetic properties were measured by vibrating sample magnetometer (VSM) and Mssbauer spectrometer. The crystalline structure of (LaCo)xSr1?xFe12?xO19 (x=0.00.4) was single M-type hexagonal phase. Magnetization under an applied maximum field of 15kOe was measured

  18. Substitution Delone Sets

    E-print Network

    Jeffrey C. Lagarias; Yang Wang

    2002-08-31

    This paper addresses the problem of describing aperiodic discrete structures that have a self-similar or self-affine structure. Substitution Delone set families are families of Delone sets (X_1, ..., X_n) in R^d that satisfy an inflation functional equation under the action of an expanding integer matrix in R^d. This paper studies such functional equation in which each X_i is a discrete multiset (a set whose elements are counted with a finite multiplicity). It gives necessary conditions on the coefficients of the functional equation for discrete solutions to exist. It treats the case where the equation has Delone set solutions. Finally, it gives a large set of examples showing limits to the results obtained.

  19. Black Art.

    ERIC Educational Resources Information Center

    Baraka, Amiri

    1987-01-01

    Discusses black art as not only an expression of black life but as revolutionary art. It must be collective, functional, and committing. It must also be anti-racist, anti-capitalist, and anti-imperialist. (LHW)

  20. Black Cohosh

    MedlinePLUS

    ... review of the black cohosh case reports of hepatotoxicity. Menopause . 2008;15(4 Pt 1):628638. ... links Related Topics Black Cohosh Products and Liver Toxicity: Update (Health Canada) Find Active Medical Research Studies ...

  1. The dynamics of technological substitutions

    Microsoft Academic Search

    Brice Dattee; David FitzPatrick; Henry Birdseye Weil

    Technological substitution is the process by which disruptive technologies replace the dominant ones in an industry. The formu lation of classical models of diffusion and substitution impose simplification co nstraints to reach analytical solvability. We use the system dynamics methodology to build upon existing models by integrating dynamic aspects derived from a broad th eoretical framework and to explore the

  2. The Elementary Substitute Teacher Questionnaire.

    ERIC Educational Resources Information Center

    Mastrian, Lou; And Others

    The purpose of this paper is to present a 50-item instrument (Appendix B) designed to assess needs for elementary school substitutes. Its use may provide valuable information for inservice training of substitute teachers, the often neglected cadre of professional educators. A priori and a posteriori validation procedures are described. A factor

  3. MICROWAVE PHOTOCHEMISTRY OF SUBSTITUTED PHENOLS

    E-print Network

    Cirkva, Vladimir

    MICROWAVE PHOTOCHEMISTRY OF SUBSTITUTED PHENOLS V. Crkva, J. Kurfrstov, M. Hjek Institute application for organic photochemistry has been shown only recently [5-11]. We disclosed the studies of microwave photochemistry of substituted phenols in an original photoche- mical reactor consisting of EDL

  4. In situ studies of zeolite syntheses using powder diffraction methods: Crystallization of ``instant zeolite A`` powder and CoAPO-5

    SciTech Connect

    Norby, P. [Odense Univ. (Denmark). Dept. of Chemistry; Christensen, A.N. [Aarhus Univ. (Denmark). Dept. of Chemistry; Hanson, J.C. [Brookhaven National Lab., Upton, NY (United States)

    1994-02-01

    A series of hydrothermal zeolite synthesis were performed on a powder diffractometer using synchrotron radiation and a position sensitive detector. Direct observation of the induction period (nucleation stage), crystallization and transformation of zeolite 4A (Na-LTA) was possible due to the intense X-ray beam which allows fast data collection. High pressure experiments were performed, allowing observation of hydrothermal synthesis of a cobalt substituted AlPO{sub 4}-zeolite, CoAPO-5, up to 165{degrees}C. The temperature dependence of crystallization rates of CoAPO-5 was studied. This is to our knowledge the first time resolved powder diffraction studies of zeolite syntheses using angle dispersive synchrotron powder diffraction.

  5. Talking Black.

    ERIC Educational Resources Information Center

    Abrahams, Roger D.

    This book contains essays which focus on the systems of communication that operate within and between various social segments of Afro-American communities in the United States. The essays are presented under the following headings: (1) "Getting Into It: Black Talk, Black Life and the Academic," (2) "'Talking My Talk': Black Talk Varieties and

  6. Black Appalachians.

    ERIC Educational Resources Information Center

    Waage, Fred, Ed.; Cabbell, Ed, Ed.

    1986-01-01

    This issue of "Now and Then" focuses on black Appalachians, their culture, and their history. It contains local histories, articles, and poems and short stories by Appalachian blacks. Articles include: "A Mountain Artist's Landscape," a profile of artist Rita Bradley by Pat Arnow; "A Part and Apart," a profile of black historian Ed Cabbell by Pat

  7. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Substituted phenyl azo substituted phenyl esters (generic name). 721.3063 Section...Chemical Substances 721.3063 Substituted phenyl azo substituted phenyl esters (generic...

  8. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Substituted phenyl azo substituted phenyl esters (generic name). 721.3063 Section...Chemical Substances 721.3063 Substituted phenyl azo substituted phenyl esters (generic...

  9. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Substituted phenyl azo substituted phenyl esters (generic name). 721.3063 Section...Chemical Substances 721.3063 Substituted phenyl azo substituted phenyl esters (generic...

  10. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Substituted phenyl azo substituted phenyl esters (generic name). 721.3063 Section...Chemical Substances 721.3063 Substituted phenyl azo substituted phenyl esters (generic...

  11. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Substituted phenyl azo substituted phenyl esters (generic name). 721.3063 Section...Chemical Substances 721.3063 Substituted phenyl azo substituted phenyl esters (generic...

  12. Synthesis and spectral characterization of silver/magnesium co-substituted hydroxyapatite for biomedical applications

    NASA Astrophysics Data System (ADS)

    Gopi, D.; Shinyjoy, E.; Kavitha, L.

    2014-06-01

    The present work is aimed at the synthesis of antibacterial and bioactive silver/magnesium co-substituted hydroxyapatite (Ag/Mg-HAP) powders. For this purpose, firstly, different concentrations (0.5, 1.5, 2.5 wt.%) of silver substituted HAP (Ag-HAP) powders were prepared by ultrasonic irradiation technique and were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). Secondly, magnesium (Mg) is co-substituted as secondary material into Ag-HAP to offset the potential cytotoxicity of Ag, as higher concentration of Ag is toxic. The antibacterial activity of as-synthesized powders was evaluated by Escherichia coli (E. coli) and was found to be effectively high against bacterial colonization. Also, the in vitro cell-material interaction is evaluated with human osteosarcoma MG63 (HOS MG63) cells for cell proliferation. The results showed the evidence of cytotoxic effects of the higher concentration of Ag-HAP characterized by poor cellular viability whereas, Ag/Mg-HAP showed better cell viability indicating that co-substitution of Mg in Ag-HAP effectively offset the negative effects of Ag and improve performance compared with pure HAP. Thus, the as synthesized Ag/Mg-HAP will serve as a better candidate for biomedical applications with good antibacterial property and bone bonding ability.

  13. Synthesis and spectral characterization of silver/magnesium co-substituted hydroxyapatite for biomedical applications.

    PubMed

    Gopi, D; Shinyjoy, E; Kavitha, L

    2014-06-01

    The present work is aimed at the synthesis of antibacterial and bioactive silver/magnesium co-substituted hydroxyapatite (Ag/Mg-HAP) powders. For this purpose, firstly, different concentrations (0.5, 1.5, 2.5wt.%) of silver substituted HAP (Ag-HAP) powders were prepared by ultrasonic irradiation technique and were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). Secondly, magnesium (Mg) is co-substituted as secondary material into Ag-HAP to offset the potential cytotoxicity of Ag, as higher concentration of Ag is toxic. The antibacterial activity of as-synthesized powders was evaluated by Escherichia coli (E. coli) and was found to be effectively high against bacterial colonization. Also, the in vitro cell-material interaction is evaluated with human osteosarcoma MG63 (HOS MG63) cells for cell proliferation. The results showed the evidence of cytotoxic effects of the higher concentration of Ag-HAP characterized by poor cellular viability whereas, Ag/Mg-HAP showed better cell viability indicating that co-substitution of Mg in Ag-HAP effectively offset the negative effects of Ag and improve performance compared with pure HAP. Thus, the as synthesized Ag/Mg-HAP will serve as a better candidate for biomedical applications with good antibacterial property and bone bonding ability. PMID:24632237

  14. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name...substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name...substituted naphthyl)azo (substituted phenyl) azo, sodium salt (PMN...

  15. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name...substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name...substituted naphthyl)azo (substituted phenyl) azo, sodium salt (PMN...

  16. Thermal evolution behavior of carbides and {gamma} Prime precipitates in FGH96 superalloy powder

    SciTech Connect

    Zhang Lin, E-mail: zhanglincsu@163.com [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); Liu Hengsan, E-mail: lhsj63@sohu.com [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); He Xinbo, E-mail: xb_he@163.com [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); Rafi-ud-din, E-mail: rafiuddi@gmail.com [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); Qu Xuanhui, E-mail: quxh@ustb.edu.cn [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); Qin Mingli, E-mail: mlqin75@hotmail.com [State Key Laboratory for Advanced Metals and Materials, Beijing Key Laboratory for Powder Metallurgy and Particulate Materials, University of Science and Technology Beijing, Beijing, 100083 (China); Li Zhou, E-mail: zhouli621@126.com [National Key Lab of High Temperature Structural Materials, Beijing Institute of Aeronautical Materials, Beijing, 100095 (China); Zhang Guoqing, E-mail: g.zhang@126.com [National Key Lab of High Temperature Structural Materials, Beijing Institute of Aeronautical Materials, Beijing, 100095 (China)

    2012-05-15

    The characteristics of rapidly solidified FGH96 superalloy powder and the thermal evolution behavior of carbides and {gamma} Prime precipitates within powder particles were investigated. It was observed that the reduction of powder size and the increase of cooling rate had transformed the solidification morphologies of atomized powder from dendrite in major to cellular structure. The secondary dendritic spacing was measured to be 1.02-2.55 {mu}m and the corresponding cooling rates were estimated to be in the range of 1.4 Multiplication-Sign 10{sup 4}-4.7 Multiplication-Sign 10{sup 5} K{center_dot}s{sup -1}. An increase in the annealing temperature had rendered the phase transformation of carbides evolving from non-equilibrium MC Prime carbides to intermediate transition stage of M{sub 23}C{sub 6} carbides, and finally to thermodynamically stable MC carbides. The superfine {gamma} Prime precipitates were formed at the dendritic boundaries of rapidly solidified superalloy powder. The coalescence, growth, and homogenization of {gamma}' precipitates occurred with increasing annealing temperature. With decreasing cooling rate from 650 Degree-Sign C{center_dot}K{sup -1} to 5 Degree-Sign C{center_dot}K{sup -1}, the morphological development of {gamma} Prime precipitates had been shown to proceed from spheroidal to cuboidal and finally to solid state dendrites. Meanwhile, a shift had been observed from dendritic morphology to recrystallized structure between 900 Degree-Sign C and 1050 Degree-Sign C. Moreover, accelerated evolution of carbides and {gamma}' precipitates had been facilitated by the formation of new grain boundaries which provide fast diffusion path for atomic elements. - Highlights: Black-Right-Pointing-Pointer Microstructural characteristic of FGH96 superalloy powder was investigated. Black-Right-Pointing-Pointer The relation between microstructure, particle size, and cooling rate was studied. Black-Right-Pointing-Pointer Thermal evolution behavior of {gamma} Prime and carbides in loose FGH96 powder was studied.

  17. Black powder drugs: an innovative response to drug control policy

    Microsoft Academic Search

    Christopher P. Krebs; Michael T. Costelloe; David Jenks

    2000-01-01

    As the intensity of the War on Drugs escalates, the social control of drug interdiction crosses international borders and employs more technologically advanced detection and apprehension tactics. In response to this intensification, drug traders develop advanced counter-surveillance strategies that diminish their chances of being detected and apprehended. This results in an interesting relationship between those who choose to indulge in

  18. How Do Substitute Teachers Substitute? An Empirical Study of Substitute-Teacher Labor Supply

    ERIC Educational Resources Information Center

    Gershenson, Seth

    2012-01-01

    This paper examines the daily labor supply of a potentially important, but often overlooked, source of instruction in U.S. public schools: substitute teachers. I estimate a sequential binary-choice model of substitute teachers' job-offer acceptance decisions using data on job offers made by a randomized automated calling system. Importantly, this

  19. 40 CFR 721.323 - Substituted acrylamide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Substituted acrylamide. 721.323 Section 721.323 ...Substances 721.323 Substituted acrylamide. (a) Chemical substance and significant...generically identified as substituted acrylamide (PMN P-90-1687) is subject...

  20. 40 CFR 721.323 - Substituted acrylamide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Substituted acrylamide. 721.323 Section 721.323 ...Substances 721.323 Substituted acrylamide. (a) Chemical substance and significant...generically identified as substituted acrylamide (PMN P-90-1687) is subject...

  1. 40 CFR 721.323 - Substituted acrylamide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Substituted acrylamide. 721.323 Section 721.323 ...Substances 721.323 Substituted acrylamide. (a) Chemical substance and significant...generically identified as substituted acrylamide (PMN P-90-1687) is subject...

  2. Storage study and quality evaluation of coconut protein powder.

    PubMed

    Naik, Aduja; Prakash, Maya; R, Ravi; Raghavarao, Ksms

    2013-11-01

    Coconut skim milk and insoluble protein are 2 major byproducts in the production of virgin coconut oil. Coconut skim milk was homogenized along with insoluble protein and spray dried to obtain a value-added product, namely, coconut protein powder (CPP). This study deals with the storage study of CPP under different conditions (refrigerated [control], ambient and accelerated). CPP samples were withdrawn periodically at designated intervals of 15 d for accelerated and control, and 30 d for ambient condition. CPP stored at different conditions exhibited marginal moisture uptake (by 0.74 % w/w for control, 0.76 % w/w for ambient, and 1.26 % w/w for accelerated condition) and as a result, had very little effect on the functional properties of the powder. Withdrawn CPP was tested for sensory quality aspects and subjected to instrumental analysis as well. Withdrawn CPP was incorporated as a milk substitute in dessert (Kheer). Quantitative descriptive analysis of the powder and product (Kheer) showed no significant difference in attributes of CPP during the storage period of 2 mo. Electronic nose analysis revealed that CPP samples were not much different with respect to aroma pattern matching, respectively. PMID:24245897

  3. Effectiveness of topical chlorhexidine powder as an alternative to hexachlorophane for the control of Staphylococcus aureus in neonates.

    PubMed

    Wilcox, M H; Hall, J; Gill, A B; Fawley, W N; Parnell, P; Verity, P

    2004-02-01

    We routinely phage-type Staphylococcus aureus isolates from high-risk inpatients each week. This surveillance approach previously identified a five-year outbreak of a methicillin-susceptible S. aureus strain (MSSA, PT 53,85), which affected 202 babies on a regional neonatal unit. We previously reported this outbreak and the multiple staged infection control measures that were required to end it. These included strict emphasis on hand hygiene, environmental and staff surveillance sampling, application of topical triclosan solution and hexachlorophane powder, aseptic handling of a skin protectant material, and use of topical mupirocin for staff nasal carriers of the endemic MSSA strain and for babies colonized or infected with S. aureus. In summer 2000 topical hexachlorophane powder became unavailable and we therefore substituted topical 1% chlorhexidine powder as part of routine umbilical decontamination. We have continued prospective S. aureus surveillance for the past five years to monitor the effect of this practice change. We observed a continued decline in the numbers of monthly MSSA isolates from neonatal unit babies. Since the substitution of chlorhexidine for hexachlorophane, the median monthly number of MRSA isolates has been 0.5 (range 0-4). Only sporadic S. aureus PT 53,85 isolates were recovered. Control of S. aureus in our regional neonatal unit, in particular an endemic MSSA strain, was maintained when topical umbilical hexachlorophane powder was substituted with 1% chlorhexidine powder. PMID:15019229

  4. Sorghum Bran, Chestnut Wood Powder, and Chardonnay Grape Seed Flour Addition Effect on Lipid Oxidation and Color in Ground Beef Patties

    E-print Network

    Roybal, Tabitha Lynn

    2012-02-14

    ., Spooner, WI), 0.1% and 0.25% chestnut wood powder (CN, Castanea sative mill, approximately 74-78% hydrolysable tannins, Chemtan? Chestnut Powder KPN, Chemtan Co., Exeter, NH), and 0.25% and 0.5% of each of the following sorghum bran varieties: black... seed (CG, Botanic Oil Innovations Inc., Spooner, WI), 0.1% chestnut (CN, Castanea sative mill, approximately 74-78% hydrolysable tannins, Chemtan? Chestnut Powder KPN, Chemtan Co., Exeter, NH), and 0.5% black sorghum bran with tannins (BTS). Patties...

  5. Thermal properties of carbon black aqueous nanofluids for solar absorption

    PubMed Central

    2011-01-01

    In this article, carbon black nanofluids were prepared by dispersing the pretreated carbon black powder into distilled water. The size and morphology of the nanoparticles were explored. The photothermal properties, optical properties, rheological behaviors, and thermal conductivities of the nanofluids were also investigated. The results showed that the nanofluids of high-volume fraction had better photothermal properties. Both carbon black powder and nanofluids had good absorption in the whole wavelength ranging from 200 to 2,500 nm. The nanofluids exhibited a shear thinning behavior. The shear viscosity increased with the increasing volume fraction and decreased with the increasing temperature at the same shear rate. The thermal conductivity of carbon black nanofluids increased with the increase of volume fraction and temperature. Carbon black nanofluids had good absorption ability of solar energy and can effectively enhance the solar absorption efficiency. PMID:21767359

  6. Vitreous substitutes: challenges and directions

    PubMed Central

    Gao, Qian-Ying; Fu, Yue; Hui, Yan-Nian

    2015-01-01

    The natural vitreous body has a fine structure and complex functions. The imitation of the natural vitreous body by vitreous substitutes is a challenging work for both researchers and ophthalmologists. Gases, silicone oil, heavy silicone oil and hydrogels, particularly the former two vitreous substitutes are clinically widely used with certain complications. Those, however, are not real artificial vitreous due to lack of structure and function like the natural vitreous body. This article reviews the situations, challenges, and future directions in the development of vitreous substitutes, particularly the experimental and clinical use of a new artificial foldable capsular vitreous body. PMID:26085987

  7. Washing powders and the environment: has TAED any influence on the complexing behaviour of phosphonic acids?

    Microsoft Academic Search

    Vronique Deluchat; Stella Lacour; Bernard Serpaud; Jean-Claude Bollinger

    2002-01-01

    Complexation properties of two phosphonic acids: nitrilotris (methylenephosphonic acid) and 1-hydroxyethane-1,1?-diphosphonic acid, with Cu(II) and Ca(II) have been previously determined by pH and ionic selective electrode titrations. These phosphonic acids are commonly added to washing powders as polyphosphate substitutes and are here studied in the presence of another detergent compound: tetraacetylethylenediamine (TAED), a bleaching activator. Product concentrations were chosen in

  8. DESIGNING ENVIRONMENTALLY BENIGN SOLVENT SUBSTITUTES

    EPA Science Inventory

    Since the signing of 1987 Montreal Protocol, reducing and eliminating the use of harmful solvents has become an internationally imminent environmental protection mission. Solvent substitution is an effective way to achieve this goal. The Program for Assisting the Replacement of...

  9. Polymer quenched prealloyed metal powder

    DOEpatents

    Hajaligol, Mohammad R. (Midlothian, VA); Fleischhauer, Grier (Midlothian, VA); German, Randall M. (State College, PA)

    2001-01-01

    A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3 % Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

  10. Calcium carbonate powder containing gentamicin for mixing with bone grafts.

    PubMed

    Coraa-Huber, Dbora; Hausdorfer, Johann; Fille, Manfred; Nogler, Michael; Khn, Klaus-Dieter

    2014-08-01

    Bone grafts are used for reconstructing bone defects caused by implant-associated complications, trauma, and tumors. Surgery with bone allografts is complex and time consuming; therefore, it is prone to a higher infection rate (2.0%-2.5%). In the case of site infection, systemically administered antibiotics cannot reach the infected bone graft. This study evaluated the use of resorbable bone graft substitute powder (HERAFILL; Heraeus Medical GmbH, Wehrheim, Germany) as a bone void-filling material as well as an antibiotic carrier for mixing with bone grafts. The antibiotic activity of the bone chips mixed with HERAFILL powder was measured by drug release tests and bacterial susceptibility with Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. HERAFILL powder was added to the bone chips (bone chips/HERAFILL; w/w = 1:1), mixed with a spatula, and vortexed for 1 minute. Gentamicin base release was evaluated in phosphate-buffered saline for up to 7 days using B subtilis bioassay. Antimicrobial efficacy was tested with S aureus and S epidermidis. The average amount of gentamicin base released from bone chips mixed with HERAFILL at 0 to 12 hours was 99.66 mg/mL. On day 7, the gentamicin base released 0.42 mg/mL. The elution released from bone chips mixed with HERAFILL promoted the formation of a zone of inhibition on S epidermidis and S aureus plates. This study confirmed the capacity of bone grafts to act as antibiotic carriers once mixed with HERAFILL powder. Bone chips mixed with HERAFILL showed efficacy against S aureus and S epidermidis. PMID:25102500

  11. Enhancement of aged and denatured fingerprints using the cyanoacrylate fuming technique following dusting with amino acid-containing powders.

    PubMed

    Nixon, Carly; Almond, Matthew J; Baum, John V; Bond, John W

    2013-03-01

    We have carried out experiments to investigate the aging of latent fingerprints deposited on black PVC over a period of 4-15 weeks. A thumbprint was used in each case and before deposition of the print the donor rubbed their thumb around their nose to add sebaceous deposits. We have studied the effect of heat, light, and moisture and we find that moisture is the most significant factor in the degradation of the latent print. We have attempted to enhance these latent prints by dusting with valine powder or powders composed of valine mixed with gold or red fluorescent commercial fingerprint powders. To make a direct comparison between "treated" and "untreated" prints, the prints were cut in half with one-half being "treated" and one-half not. Our studies show the best results being obtained when powders of valine and red fluorescent powders are applied prior to cyanoacrylate fuming. PMID:23316682

  12. Mechanochemical synthesis of ultrafine Ti(C,N)Al 2O 3 composite powders and phase transformation

    Microsoft Academic Search

    D. P. Xiang; Y. Liu; M. J. Tu; Y. Y. Li; S. Xia; B. Q. Chen

    2009-01-01

    Titanium carbonitridealumina (Ti(C,N)Al2O3) composite powders with ultrafine-sized particles below 0.5?m were successfully synthesized by mechanochemical method. That is to say, mixed powders of anatase\\/aluminum\\/carbon black were mechanically milled for 40h under N2\\/Ar atmosphere and were subsequently vacuum heat treated for 1h at 8001100C. From X-ray diffraction (XRD) and thermogravimetrydifferential scanning calorimetry (TGADSC) results of milled powders, Ti(C,N)Al2O3 phases were formed

  13. Intradermal needle-free powdered drug injection

    E-print Network

    Liu, John (John Hsiao-Yung)

    2012-01-01

    This thesis presents a new method for needle-free powdered drug injection. The design, construction, and testing of a bench-top helium-powered device capable of delivering powder to controllable depths within the dermis ...

  14. Review: aqueous tape casting of ceramic powders

    Microsoft Academic Search

    D. Hotza; P. Greil

    1995-01-01

    Slurry formulations and processing parameters of the water-based tape casting of ceramic powders are reviewed. Additives include binders, like cellulose ethers, vinyl or acrylic-type polymers; plasticizers, like glycols; and dispersants, like ammonium salts of poly(acrylic acids). Mostly alumina powders have been employed. Hydrophobing of ceramic powders permits the aqueous processing even of water-reactive powders, like aluminium nitride. Non-toxicity and non-inflammability

  15. Homogeneous precipitation of nickel hydroxide powders

    NASA Astrophysics Data System (ADS)

    Mavis, Bora

    Structure of nickel precipitate from decomposition of urea was found to be alpha-Ni(OH)2. FTIR analysis revealed the intercalation of cyanate (OCN), which is an intermediate product of urea decomposition. This observation implied that the assumption of single step decomposition of urea to carbon dioxide and ammonia was over simplified. Role of critical experimental parameters like initial pH and metal ion concentration on the powder characteristics was carried out. Numerical solutions to reaction pathways predicted significant accumulation of the intermediate cyanate in the time-temperature range investigated. Numerical simulations included the effects of hydrolysis products of Ni2+ and Ni-amine, Ni-cyanate, and Ni-carbonate complexes. Chemical analysis of the precipitate showed a decrease in nitrogen content with increasing reaction times. This was consistent with the predicted decrease in concentration of Ni-cyanate complexes with time. Layer double hydroxides (LDHs) are intercalation compounds represented by the formula [M2+1-xM3+ x(OH)2]x+[An-x/n ]x-mH2O. alpha-Ni(OH) 2 and Ni-Al layer double hydroxides precipitated by urea were investigated with FTIR and XPS. The role of cyanate in nucleation and growth of precipitates is demonstrated. In the early stages, cyanate ion is found mainly to be grafted into alpha-Ni(OH)2 via nitrogen, whereas later in the growth stages, it is bonded through oxygen. In LDHs cyanate remains N-bonded. Precipitation with substituted ureas, revealed the link between spectral features and structures observed in XRD patterns. With slower decomposition rates and low levels of supersaturation an extensively hydrated structure was observed. From the two phases of Ni(OH)2, alpha-phase, with its larger interlayer spacing, offers enhanced electrochemical properties but it transforms into thermodynamically stable beta-phase. Stabilizing effects of Ni2+ substitution with Co2+ and Al3+ was investigated. A number of three-component LDHs (TCLDHs) with Ni2+1-(x+y) /Co2+x and Al3+y (x and y were varied between 0.00 and, 0.25) were produced by urea precipitation. From the compositions studied, the ones containing [Al3+] o ? 0.015 M resulted with the LDH structure and proved to be stable in the electrolyte for prolonged times. Chronopotentiometry results indicated that TC-LDHs could deliver capacities up to about 30% higher than the beta-phase.

  16. Human periodontal ligament cell viability in milk and milk substitutes.

    PubMed

    Pearson, Robert M; Liewehr, Frederick R; West, Leslie A; Patton, William R; McPherson, James C; Runner, Royce R

    2003-03-01

    The purpose of this study was to determine the efficacy of several milk substitutes compared to whole milk in maintaining the viability of human periodontal ligament (PDL) cells on avulsed teeth. PDL cells were obtained from freshly extracted, healthy third molars and cultured in Eagle's minimal essential media (EMEM). The cells were plated onto 24-well culture plates and allowed to attach for 24 h. EMEM was replaced with refrigerated whole milk (positive control), reconstituted powdered milk, evaporated milk, or one of two baby formulas (Similac or Enfamil). Tap water served as the negative control. Tissue culture plates were incubated with the experimental media at 37 degrees C for 1, 2, 4, or 8 h. Cell viability was determined by a cell proliferation assay (CellTiter 96 AQ Assay), with absorbance read at 450 nM. A two-way ANOVA (p < 0.001) indicated that at 1 h there was no difference in the effect on PDL cell viability between any of the materials and whole milk. At 2 h, Enfamil and Similac performed significantly better than whole milk, whereas evaporated milk performed worse. At 4 h, Enfamil performed better than whole milk, whereas all other milk substitutes performed worse. At 8 h, all substitutes performed worse than whole milk. These results suggest that Enfamil, which is supplied in powder form that does not require special storage and has a shelf life of 18 months, is a more effective storage medium for avulsed teeth than pasteurized milk for at least 4 h. PMID:12669877

  17. 21 CFR 524.1005 - Furazolidone powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Furazolidone powder. 524.1005 Section 524... 524.1005 Furazolidone powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  18. Agglomeration of Food Powder and Applications

    Microsoft Academic Search

    K. Dhanalakshmi; S. Ghosal; S. Bhattacharya

    2011-01-01

    Agglomeration has many applications in food processing and major applications include easy flow table salt, dispersible milk powder and soup mix, instant chocolate mix, beverage powder, compacted cubes for nutritional-intervention program, health bars using expanded\\/puffed cereals, etc. The main purpose of agglomeration is to improve certain physical properties of food powders such as bulk density, flowability, dispersability, and stability. Agglomerated

  19. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  20. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  1. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  2. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  3. 21 CFR 73.1647 - Copper powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Copper powder. 73.1647 Section 73.1647...FROM CERTIFICATION Drugs 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing...

  4. Effect of Powder Polydispersity on Aerosol Generation

    Microsoft Academic Search

    Nora Y. K. Chew; Hak-Kim Chan

    Purpose. We investigated the effect of primary powder polydispersity on the generation of pharmaceutical powder aerosols, using mannitol and bovine serum albu- min (BSA) as the model compounds. Methods. Primary powders with different polydispersity but comparable physical and mass median aerodynamic diameter (MMAD) were obtained from spray drying. The polydispersity, i.e. the width of the particle size distribution, of the

  5. Partitioning the Variation in Mammalian Substitution Rates

    Microsoft Academic Search

    Nick G. C. Smith; Adam Eyre-Walker

    2003-01-01

    We have used analysis of variance to partition the variation in synonymous and amino acid substitution rates between three effects (gene, lineage, and a gene-by-lineage interaction) in mammalian nuclear and mitochondrial genes. We find that gene effects are stronger for amino acid substitution rates than for synonymous substitution rates and that lineage effects are stronger for synonymous substitution rates than

  6. Are black holes totally black?

    E-print Network

    A. A. Grib; Yu. V. Pavlov

    2014-10-21

    Geodesic completeness needs existence near the horizon of the black hole of "white hole" geodesics coming from the region inside of the horizon. Here we give the classification of all such geodesics with the energies $E/m \\le 1$ for the Schwarzschild and Kerr's black hole. The collisions of particles moving along the "white hole" geodesics with those moving along "black hole" geodesics are considered. Formulas for the increase of the energy of collision in the centre of mass frame are obtained and the possibility of observation of high energy particles arriving from the black hole to the Earth is discussed.

  7. Black Cohosh

    MedlinePLUS

    ... PubMed abstract ] Gruenwald J: Standardized black cohosh (Cimicifuga) extract clinical monograph. Quarterly Review of Natural Medicine Summer: 117-125, 1998. Whiting PW, Clouston A, Kerlin P: Black cohosh and other herbal remedies associated with acute hepatitis. Medical Journal of ...

  8. MESOSCALE SIMULATIONS OF POWDER COMPACTION

    SciTech Connect

    Lomov, Ilya; Fujino, Don; Antoun, Tarabay; Liu, Benjamin [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore CA 94551 (United States)

    2009-12-28

    Mesoscale 3D simulations of shock compaction of metal and ceramic powders have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating a well-characterized shock compaction experiment of a porous ductile metal. Simulation results using the Steinberg material model and handbook values for solid 2024 aluminum showed good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not as well studied as metals, so a simple material model for solid ceramic (tungsten carbide) has been calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powders have been performed and showed good agreement with experimental data. The numerical shock wave profile has same character and thickness as that measured experimentally using VISAR. The numerical results show reshock states above the single-shock Hugoniot line as observed in experiments. We found that for good quantitative agreement with experiments 3D simulations are essential.

  9. Particle adhesion in powder coating

    SciTech Connect

    Mazumder, M.K.; Wankum, D.L.; Knutson, M.; Williams, S. [Univ. of Arkansas, Little Rock, AR (United States); Banerjee, S. [Univ. of Georgia, Athens, GA (United States)

    1996-12-31

    Electrostatic powder coating is a widely used industrial painting process. It has three major advantages: (1) it provides high quality durable finish, (2) the process is environmentally friendly and does not require the use of organic solvents, and (3) it is economically competitive. The adhesion of electrostatically deposited polymer paint particles on the grounded conducting substrate depends upon many parameters: (a) particle size and shape distributions, (b) electrostatic charge distributions, (c) electrical resistivity, (d) dielectric strength of the particles, (e) thickness of the powder film, (f) presence and severity of the back corona, and (g) the conductivity and surface properties of the substrate. The authors present a model on the forces of deposition and adhesion of corona charged particles on conducting substrates.

  10. The Black Family and Black Community Development

    Microsoft Academic Search

    Robert C. Johnson

    1981-01-01

    Black family life is discussed in the context of Black community development. The author contends that mutual, interactive actions by Black families and Black community institutions could benefit both. The familial functions of socialization (including racial conscious ness) and economic functioning are reviewed, and the ways that Black families can assist in the development of the Black community through efficient

  11. Analysis of powder diffraction data

    Microsoft Academic Search

    M. J. Cooper

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H.M. Rietveld, Acta. Cryst. 2, 151-152 (1967): J. Appl. Cryst. 2, 65-71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C.P. Clarke and J.S. Rollett, Acta. Cryst.

  12. Anti-Corrosive Powder Particles

    NASA Technical Reports Server (NTRS)

    Parker, Donald; MacDowell, Louis, III

    2005-01-01

    The National Aeronautics and Space Administration (NASA) seeks partners for a new approach in protecting embedded steel surfaces from corrosion. Corrosion of reinforced steel in concrete structures is a significant problem for NASA structures at Kennedy Space Center (KSC) because of the close proximity of the structures to salt spray from the nearby Atlantic Ocean. In an effort to minimize the damage to such structures, coatings were developed that could be applied as liquids to the external surfaces of a substrate in which the metal structures were embedded. The Metallic Pigment Powder Particle technology was developed by NASA at KSC. This technology combines the metallic materials into a uniform particle. The resultant powder can be sprayed simultaneously with a liquid binder onto the surface of concrete structures with a uniform distribution of the metallic pigment for optimum cathodic protection of the underlying steel in the concrete. Metallic Pigment Powder Particle technology improves upon the performance of an earlier NASA technology Liquid Galvanic Coating (U.S. Patent No. 6,627,065).

  13. The iron powder test for naphthenic acid corrosion studies

    SciTech Connect

    Hau, J.L.; Yepez, O.; Specht, M.I.; Lorenzo, R. [PDVSA-Intevep, Caracas (Venezuela)

    1999-11-01

    In the course of an ongoing investigation into the phenomenon of naphthenic acid corrosion, a new test method has evolved and is currently being further developed to substitute the total acid number (TAN or neutralization number) as an indicator for naphthenic acid corrosion potential. It can also be used to complement conventional autoclave corrosion tests in high temperature environments, which are based on weight loss of steel coupons. In this new method an oil sample reacts with pure iron powder within an autoclave heated to the testing temperature. The result is based on the amount of dissolved iron found in the oil sample. The oil sample can dissolve an amount of iron for a given time at a given temperature, depending on the naphthenic acid corrosion, since these acids react with iron to produce oil soluble iron naphthenates. This paper describes the method, compares it with conventional crude corrosiveness testing, and proposes it as a new way of measuring naphthenic acid corrosion potential.

  14. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...phenyl azo substituted benzenediazonium salt. 721.1555 Section 721.1555 ...phenyl azo substituted benzenediazonium salt. (a) Chemical substance and significant...phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject to...

  15. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...phenyl azo substituted benzenediazonium salt. 721.1555 Section 721.1555 ...phenyl azo substituted benzenediazonium salt. (a) Chemical substance and significant...phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject to...

  16. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...phenyl azo substituted benzenediazonium salt. 721.1555 Section 721.1555 ...phenyl azo substituted benzenediazonium salt. (a) Chemical substance and significant...phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject to...

  17. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...azo substituted sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 ...azo substituted sulfocarbopolycle, sodium salt. (a) Chemical substance and significant...azo substituted sulfocarbopolycle, sodium salt (PMN P-96-1263) is subject to...

  18. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Copper complex of (substituted sulfonaphthyl...Specific Chemical Substances 721.2577 Copper complex of (substituted sulfonaphthyl...chemical substances identified generically as copper complex of (substituted...

  19. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Copper complex of (substituted sulfonaphthyl...Specific Chemical Substances 721.2577 Copper complex of (substituted sulfonaphthyl...chemical substances identified generically as copper complex of (substituted...

  20. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...phenyl azo substituted benzenesulfonic acid copper compound (generic). 721.10126...phenyl azo substituted benzenesulfonic acid copper compound (generic). (a) Chemical...phenyl azo substituted benzenesulfonic acid copper compound (PMN P-06-689) is...

  1. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...phenyl azo substituted benzenesulfonic acid copper compound (generic). 721.10126...phenyl azo substituted benzenesulfonic acid copper compound (generic). (a) Chemical...phenyl azo substituted benzenesulfonic acid copper compound (PMN P-06-689) is...

  2. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Copper complex of (substituted sulfonaphthyl...Specific Chemical Substances 721.2577 Copper complex of (substituted sulfonaphthyl...chemical substances identified generically as copper complex of (substituted...

  3. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Copper complex of (substituted sulfonaphthyl...Specific Chemical Substances 721.2577 Copper complex of (substituted sulfonaphthyl...chemical substances identified generically as copper complex of (substituted...

  4. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...phenyl azo substituted benzenesulfonic acid copper compound (generic). 721.10126...phenyl azo substituted benzenesulfonic acid copper compound (generic). (a) Chemical...phenyl azo substituted benzenesulfonic acid copper compound (PMN P-06-689) is...

  5. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Copper complex of (substituted sulfonaphthyl...Specific Chemical Substances 721.2577 Copper complex of (substituted sulfonaphthyl...chemical substances identified generically as copper complex of (substituted...

  6. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). 721.5340 Section...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). (a) Chemical...benzothiazole-azo-substituted benzoquinoline nickel complex (PMN P-99-897) is...

  7. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). 721.5340 Section...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). (a) Chemical...benzothiazole-azo-substituted benzoquinoline nickel complex (PMN P-99-897) is...

  8. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). 721.5340 Section...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). (a) Chemical...benzothiazole-azo-substituted benzoquinoline nickel complex (PMN P-99-897) is...

  9. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). 721.5340 Section...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). (a) Chemical...benzothiazole-azo-substituted benzoquinoline nickel complex (PMN P-99-897) is...

  10. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). 721.5340 Section...benzothiazole-azo-substituted benzoquinoline nickel complex (generic). (a) Chemical...benzothiazole-azo-substituted benzoquinoline nickel complex (PMN P-99-897) is...

  11. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...phenyl azo substituted benzenesulfonic acid copper compound (generic). 721.10126...triazine amino substituted benezenesulfonic acid reaction product with...

  12. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...phenyl azo substituted benzenesulfonic acid copper compound (generic). 721.10126...triazine amino substituted benezenesulfonic acid reaction product with...

  13. Substituted decision making: elder guardianship.

    PubMed

    Leatherman, Martha E; Goethe, Katherine E

    2009-11-01

    The goal of this column is to help experienced clinicians navigate the judicial system when they are confronted with requests for capacity evaluations that involve guardianship (conservatorship). The interface between the growing elderly medical population and increasing requests for substituted decision making is becoming more complex. This column will help practicing psychiatrists understand the medical, legal, and societal factors involved in adult guardianship. Such understanding is necessary in order to effectively perform guardianship evaluations and adequately inform courts, patients, and families about the psychiatric diagnoses central to substituted decision making. PMID:19934723

  14. Novel Approaches to Improve the Intrinsic Microbiological Safety of Powdered Infant Milk Formula

    PubMed Central

    Kent, Robert M.; Fitzgerald, Gerald F.; Hill, Colin; Stanton, Catherine; Ross, R. Paul

    2015-01-01

    Human milk is recognised as the best form of nutrition for infants. However; in instances where breast-feeding is not possible, unsuitable or inadequate, infant milk formulae are used as breast milk substitutes. These formulae are designed to provide infants with optimum nutrition for normal growth and development and are available in either powdered or liquid forms. Powdered infant formula is widely used for convenience and economic reasons. However; current manufacturing processes are not capable of producing a sterile powdered infant formula. Due to their immature immune systems and permeable gastro-intestinal tracts, infants can be more susceptible to infection via foodborne pathogenic bacteria than other age-groups. Consumption of powdered infant formula contaminated by pathogenic microbes can be a cause of serious illness. In this review paper, we discuss the current manufacturing practices present in the infant formula industry, the pathogens of greatest concern, Cronobacter and Salmonella and methods of improving the intrinsic safety of powdered infant formula via the addition of antimicrobials such as: bioactive peptides; organic acids; probiotics and prebiotics. PMID:25685987

  15. Skin Substitutes and Wound Healing

    Microsoft Academic Search

    F. A. Auger; D. Lacroix; L. Germain

    2009-01-01

    Medical science has vastly improved on the means and methods available for the treatment of wounds in the clinic. The production and use of various types of skin substitutes has led to dramatic improvements in the odds of survival for severely burned patients, but they have also shown promise for many other applications, including cases involving chronic wounds that are

  16. C?H Bond Activation by Pd-substituted CeO[subscript 2]: Substituted Ions versus Reduced Species

    SciTech Connect

    Misch, Lauren M.; Kurzman, Joshua A.; Derk, Alan R.; Kim, Young-Il; Seshadri, Ram; Metiu, Horia; McFarland, Eric W.; Stucky, Galen D. (Yeungnam); (UCSB)

    2012-02-07

    Substituted metal oxides containing ionic species have been attracting a great deal of attention because of their potential ability to reduce the usage of precious metals in heterogeneous catalysts. We investigate Pd-substituted CeO{sub 2} for C-H bond activation reactions including the partial oxidation and dry reforming of CH{sub 4}. This catalyst has been previously studied for CO oxidation, NO{sub x} reduction, and the water-gas shift reaction. Pd-substituted CeO{sub 2}, Ce{sub 1-x}Pd{sub x}O{sub 2-{delta}}, was prepared as a powder with high surface area and a hollow sphere morphology using ultrasonic spray pyrolysis. The catalysts were extensively characterized using synchrotron X-ray diffraction and other techniques, confirming phase pure samples up to 10 mol % Pd substitution. Ce{sub 0.95}Pd{sub 0.05}O{sub 2-{delta}} was found to be active for partial oxidation of CH{sub 4} around 500 C and higher. Our studies, including postcatalytic synchrotron diffraction, suggest that the single-phase Ce{sub 1-x}Pd{sub x}O{sub 2-{delta}} material is not the active species and that catalysis occurs instead over the reduced two-phase Pd{sup 0}/CeO{sub 2}. This observation has been further confirmed by verifying the activity of the reduced Pd{sup 0}/CeO{sub 2} catalysts for ethylene hydrogenation, a reaction that is known to require Pd{sup 0}.

  17. Improved critical current density in ex situ processed carbon-substituted MgB2 tapes by Mg addition

    NASA Astrophysics Data System (ADS)

    Fujii, H.; Ozawa, K.; Kitaguchi, H.

    2012-06-01

    We have studied the effect of planetary ball-milling of filling powder with mineral oil on the carbon substitution and the critical current density (Jc) of Fe-sheathed MgB2 tapes fabricated through an ex situ process in a powder-in-tube (PIT) technique. Although tapes using powder with oil treatment show weak coupling, the Jc properties of those tapes are enhanced due to carbon substitution for boron. The ball-milling treatment with the oil on the filling powder with Mg addition further enhances the Jc property of tapes. The Jc values of the tapes reach about 9 kA cm-2 at 4.2 K and 10 T. The ball-milling produces a fresh clean surface by the grinding of large grains with a damaged surface and promotes a carbon substitution reaction. Mg addition compensates for the deviation in composition which occurs in the reaction. Some of the boron which is released from MgB2 at the reaction can act as an obstacle to the supercurrent path. The additional Mg consumes the boron at the formation of MgB2 and improves the grain coupling.

  18. Process for the synthesis of iron powder

    DOEpatents

    Welbon, W.W.

    1983-11-08

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder. 2 figs.

  19. Process for the synthesis of iron powder

    DOEpatents

    Not Available

    1982-03-06

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

  20. Powder handling for automated fuel processing

    SciTech Connect

    Frederickson, J.R.; Eschenbaum, R.C.; Goldmann, L.H.

    1989-04-09

    Installation of the Secure Automated Fabrication (SAF) line has been completed. It is located in the Fuel Cycle Plant (FCP) at the Department of Energy's (DOE) Hanford site near Richland, Washington. The SAF line was designed to fabricate advanced reactor fuel pellets and assemble fuel pins by automated, remote operation. This paper describes powder handling equipment and techniques utilized for automated powder processing and powder conditioning systems in this line. 9 figs.

  1. The Crisis in Black and Black.

    ERIC Educational Resources Information Center

    Hutchinson, Earl Ofari

    These essays explore why the historic conflict between blacks and whites in the United States has become a crisis that divides many African Americans. The changing racial dynamic is not marked by conflicts. between the black middle class and the poor, black men and women, the black intellectual elite and rappers, black politicians and the urban

  2. 40 CFR 721.1925 - Substituted carboheterocyclic butane tetracarboxylate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... false Substituted carboheterocyclic butane tetracarboxylate (generic). 721...1925 Substituted carboheterocyclic butane tetracarboxylate (generic). (a...generically as substituted carboheterocyclic butane tetracarboxylate (PMNs...

  3. 40 CFR 721.1925 - Substituted carboheterocyclic butane tetracarboxylate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Substituted carboheterocyclic butane tetracarboxylate (generic). 721...1925 Substituted carboheterocyclic butane tetracarboxylate (generic). (a...generically as substituted carboheterocyclic butane tetracarboxylate (PMNs...

  4. 40 CFR 721.1925 - Substituted carboheterocyclic butane tetracarboxylate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... false Substituted carboheterocyclic butane tetracarboxylate (generic). 721...1925 Substituted carboheterocyclic butane tetracarboxylate (generic). (a...generically as substituted carboheterocyclic butane tetracarboxylate (PMNs...

  5. Low cost photovoltaic modules based on dye sensitized nanocrystalline titanium dioxide and carbon powder

    Microsoft Academic Search

    Andreas Kay; Michael Grtzel

    1996-01-01

    A new type of photovoltaic module based on monolithically series connected dye sensitized photoelectrochemical cells is described. Each solar cell element consists of three porous layers on a transparent conducting substrate, namely a photoelectrode of dye sensitized nanocrystalline TiO2 (anatase), a spacer of electrically insulating, light reflecting particles of TiO2 (rutile), and a counterelectrode of graphite powder and carbon black.

  6. Thixoforming of Stellite Powder Compacts

    NASA Astrophysics Data System (ADS)

    Hogg, S. C.; Atkinson, H. V.; Kapranos, P.

    2007-04-01

    Thixoforming involves processing metallic alloys in the semi-solid state. The process requires the microstructure to be spheroidal when part-solid and part-liquid i.e. to consist of solid spheroids surrounded by liquid. The aim of this work was to investigate whether powder compacts can be used as feedstock for thixoforming and whether the consolidating pressure in the thixoformer can be used to remove porosity from the compact. The powder compacts were made from stellite 6 and stellite 21 alloys, cobalt-based alloys widely used for e.g. manufacturing prostheses. Isothermal heat treatments of small samples in the consolidated state showed the optimum thixoforming temperature to be in the range 1340C-1350C for both materials. The alloys were thixoformed into graphite dies and flowed easily to fill the die. Porosity in the thixoformed components was lower than in the starting material. Hardness values at various positions along the radius of the thixoformed demonstrator component were above the specification for both alloys.

  7. Synthesis of mullite powders by acrylamide polymerization.

    SciTech Connect

    Sin, A.; Picciolo, J. J.; Lee, R. H.; Gutierrez-Mora, F.; Goretta, K. C.; Energy Technology; INPG-CNRS

    2001-09-01

    Mullite (3Al{sub 2}O{sub 3} {center_dot} 2SiO{sub 2}) ceramics and composites are widely used. Synthesis of mullite powders, especially those that can be readily sintered, remains a focus of much current research. In support of recent efforts to fabricate mullite fibrous monoliths and to use superplastic flow to join ceramics, we have looked to synthesize reactive mullite powders. Recent advances in application of acrylamide polymers to ceramic synthesis offer promise of obtaining large quantities of high-quality powder at relatively low cost. We report here on synthesis from acrylamide monomers of mullite powders of two interesting particle sizes.

  8. Dendritic microstructure in argon atomized superalloy powders

    NASA Technical Reports Server (NTRS)

    Tewari, S. N.; Kumar, Mahundra

    1986-01-01

    The dendritic microstructure of atomized nickel base superalloy powders (Ni-20 pct Cr, NIMONIC-80A, ASTROALOY, and ZHS6-K) was studied. Prealloyed vacuum induction melted ingots were argon-atomized, the powders were cooled to room temperature, and various powder-size fractions were examined by optical metallography. Linear correlations were obtained for the powder size dependence of the secondary dendrite arm spacing, following the expected d-alpha (R) to the m power dependence on the particle size for all four superalloy compositions. However, the Ni-20 pct Cr alloy, which had much coarser arm spacing as compared to the other three alloys, had a much larger value of m.

  9. Coupled substitutions in the tourmaline group

    Microsoft Academic Search

    Franklin F. Foit; Philip E. Rosenberg

    1977-01-01

    Statistical analysis of 136 natural tourmaline compositions from the literature reveals the presence and extent of coupled substitutions involving several cations and structural sites. In schorls and dravites these are a dehydroxylation type substitution (1) (OH)-+R2+ = R3++O2- and an alkali-defect type substitution (2) R++R2+ = R3++?, Al3+ being the predominant R3+ action. Substitution (1) which represents solid solution towards

  10. Evaluation of suitable porosity for sintered porous {beta}-tricalcium phosphate as a bone substitute

    SciTech Connect

    Park, Jin-Hong; Bae, Ji-Yong [School of Mechanical Systems Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757 (Korea, Republic of)] [School of Mechanical Systems Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757 (Korea, Republic of); Shim, Jaebum [INJECTA Inc., 1511 Gwanyang-dong, Dongan-gu, Anyang-si, 431-809 (Korea, Republic of)] [INJECTA Inc., 1511 Gwanyang-dong, Dongan-gu, Anyang-si, 431-809 (Korea, Republic of); Jeon, Insu, E-mail: i_jeon@chonnam.ac.kr [School of Mechanical Systems Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757 (Korea, Republic of)] [School of Mechanical Systems Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757 (Korea, Republic of)

    2012-09-15

    Structural and mechanical characterization is performed for sintered porous beta tricalcium phosphate ({beta}-TCP) to determine the appropriate porosity for use as a bone substitute. Four different types of porous {beta}-TCP specimen with different porosities are fabricated through a sintering process. For structural characterization, scanning electron microscopy and a Microfocus X-ray computed tomography system are used to investigate the pore openings on the specimen's surface, pore size, pore distribution, and pore interconnections. Compression tests of the specimens are performed, and mechanical properties such as the elastic modulus and compressive strength are obtained. Also, the geometric shape and volume of the {beta}-TCP around the contact region of two pores, which need to be initially resolved after implantation in order to increase the size of the pore openings, are evaluated through simple calculations. The results show that porous {beta}-TCP with 42.1% porosity may be a suitable bone substitute candidate in terms of sustaining external loads, and inducing and cultivating bone cells. - Highlights: Black-Right-Pointing-Pointer Structural and mechanical characterization was performed for sintered porous {beta}-TCP specimens. Black-Right-Pointing-Pointer For structural characterization, SEM and Microfocus X-ray CT system were used. Black-Right-Pointing-Pointer For mechanical characterization, compression tests were performed. Black-Right-Pointing-Pointer Porous {beta}-TCP with 42.1% porosity may be a suitable bone substitute.

  11. Synthesis of La{sup 3+} doped nanocrystalline ceria powder by urea-formaldehyde gel combustion route

    SciTech Connect

    Biswas, M. [Central Glass and Ceramic Research Institute, Kolkata 700 032 (India)] [Central Glass and Ceramic Research Institute, Kolkata 700 032 (India); Bandyopadhyay, S., E-mail: sbando@cgcri.res.in [Central Glass and Ceramic Research Institute, Kolkata 700 032 (India)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Nano LC synthesized by gel combustion, using urea-formaldehyde fuel for first time. Black-Right-Pointing-Pointer Largely single crystals were produced in average range of 20-30 nm. Black-Right-Pointing-Pointer La{sup 3+} doping increases cell dimension linearly. Black-Right-Pointing-Pointer La{sup 3+} doping introduces ionic point defects but does not change electronic band gap. Black-Right-Pointing-Pointer Presence of Ce{sup 3+} indicates that this synthesis route produces reactive powders. -- Abstract: Nanocrystalline ceria powders doped with various concentrations of lanthanum oxide have been prepared following gel combustion route using for the first time urea-formaldehyde as fuel. The synthesized products were characterized by XRD, FESEM, TEM, PL and UV-vis spectroscopy. Peak positions of XRD were refined and the lattice parameters were obtained by applying Cohen's method. Unit cell parameter increases with concentration of La{sup 3+} ion and the variation is consistently linear. XRD calculations showed the dependence of crystallite size on dopant concentrations at lower level. TEM observation revealed unagglomerated particles to be single crystals in the average range of 20-30 nm. Band gap of the La{sup 3+} doped ceria materials does not change with doping. Spectroscopic experiments proved the existence of Ce{sup 3+} in the formed powder.

  12. Establishing a Child Care Substitute Caregiver System.

    ERIC Educational Resources Information Center

    Love, Lynne

    Substitute caregivers are needed by day care centers in every state. Indeed, some areas are experiencing severe shortages of applicants for child care positions and short-term substitute work. This article describes problems encountered in current substitute caregiver systems and suggests ways of dealing with such problems. Specifically discussed

  13. Efficient Cryptanalysis of Homophonic Substitution Amrapali Dhavare

    E-print Network

    Stamp, Mark

    technique to the "Zodiac 340" cipher, which is an unsolved message created by the infamous Zodiac killer. Keywords: homophonic substitution cipher, simple substitution cipher, hill climb, heuristic search, Zodiac. Our motivation for considering homophonic substitution ciphers is the unsolved "Zodiac 340," which

  14. Ethynyl and substituted ethynyl-terminated polysulfones

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M. (inventor)

    1984-01-01

    Ethynyl and substituted ethynyl-terminated polysulfones and a process for preparing the same are disclosed. These polysulfones are thermally cured to induce cross-linking and chain extension, producing a polymer system with improved solvent resistance and use temperature. Also disclosed are substituted 4-ethynylbenzoyl chlorides as precursors to the substituted ethynyl-terminated polysulfones and a process for preparing the same.

  15. Drying of sweet whey using drum dryer technique and utilization of the produced powder in French-type bread and butter cookies.

    PubMed

    Mustafa, L; Alsaed, A K; Al-Domi, H

    2014-06-01

    The objective of this study was to dry sweet liquid whey using drum dryer and to utilize the whey powder in French-type bread and cookies as a sugar substitute. The sweet whey powder was characterized chemically for ash, moisture, water activity, protein, salt, acidity and lactose contents. Optimization parameters including drying temperature, drum speed and starch addition for whey drying by drum dryer were tested to produce the best powder characteristics. The optimum temperature was 140C at a drum speed of 20 rpm with a corn starch level of 2% (weight per weight). Sweet whey powder produced was used as a sugar replacer in French-type bread and butter cookies at substitution levels of 25, 50 and 75% of total sugars. The developed products were analyzed chemically and sensorially. The two developed products were relatively high in protein, ash, lactose and salts compared to the control samples. Regarding the sensory evaluation, the results showed that the sugar substitution of 25 and 50% in bread and cookies were significantly (p<0.05) better than the control. It can be concluded that sweet whey powder can significantly improve the quality of the studied bakery items. PMID:26035954

  16. Black Literature vs. Black Studies: Three Lynchings

    ERIC Educational Resources Information Center

    Williams, Melvin G.

    1977-01-01

    Considers three works by black authors, all dealing with lynchings, that may be used in a black literature course to introduce students to the esthetic dimension of black literature, as well as to its cultural and racial significance. (GW)

  17. The Effect of Powder Recycling in Direct Metal Laser Deposition on Powder and Manufactured Part Characteristics

    Microsoft Academic Search

    P. A. Carroll; A. J. Pinkerton; J. Allen; W Syed; H Sezer; P. Brown; G. Ng; L. Li

    A potential way of improving the material efficiency and cost effectiveness of the Direct Metal Laser Deposition (DMLD) process is to take powder that is not utilised in each deposition attempt and re-use it in subsequent attempts (powder recycling). Currently, this is not widely implemented for fear of a detrimental effect on part quality. This study examines how powder recycling,

  18. Field studies on sugar substitutes.

    PubMed

    Scheinin, A

    1985-09-01

    Four field studies assessing the caries preventive value of partial substitution of sucrose by xylitol or a mixture of xylitol and sorbitol were recently conducted. The trials (in Thailand, Hungary and two in French Polynesia) had certain common features, i.e. protocols approved by the WHO; low intake of polyol(s); non-randomized young study populations, differing baseline caries prevalences between groups; and planned duration of 32-36 months. Analysis of the findings was facilitated through the use of rates to measure caries increments expressed as DMF teeth and surface counts in relation to the numbers of teeth at risk. Irrespective of baseline differences, all studies revealed, in comparison to known methods, that partial substitution of sucrose was associated with a preventive effect. PMID:3902660

  19. The preparation and properties of glass powder reinforced epoxy resin

    Microsoft Academic Search

    Haifeng Wang; Wenjue Han; Haibing Tian; Yimin Wang

    2005-01-01

    A sealing composites were prepared by mixing superfine glass powder and epoxy resin. The effect of active agent (stearate) on glass powder size and size distribution and the effect of surface treatment of the glass powder on the microstructure and the mechanical properties of glass powder\\/epoxy composites were investigated. Glass powder size was measured using a laser particle size analyzer.

  20. Currency Substitution and Financial Innovation

    Microsoft Academic Search

    Pablo E Guidotti

    1993-01-01

    This paper explores the domestic effects as well as the international transmission of financial innovation. The analysis is carried out in a cash-in-advance model with two currencies and tw o goods in which income velocity is variable because of inventory-type considerations in the determination of the demand for money. The discussion emphasizes the role of currency substitution, which occur s

  1. Resonant photodissociation in substituted benzenes

    NASA Astrophysics Data System (ADS)

    Scarborough, Tim; McAcy, Collin; Foote, David; Uiterwaal, Cornelis

    2011-05-01

    Cyclic aromatic molecules are abundant in organic chemistry, with a wide variety of applications, including pharmacology, pollution studies and genetic research. Among the simplest of these molecules is benzene (C6H6) , with many relevant molecules being benzene-like with a single atomic substitution. In such a substitution, the substituent determines a characteristic perturbation of the electronic structure of the molecule. We discuss the substitution of halogens into the ring (C6H5X), and its effects on the dynamics of ionization and dissociation of the molecule without the focal volume effect. In particular, using 800-nm, 50-fs laser pulses, we present results in the dissociation of fluorobenzene, chlorobenzene, bromobenzene and iodobenzene into the phenyl ring (C6H5) and the atomic halogen, and the subsequent ionization of these fragments. The impact of the ``heavy atom effect'' on a 1 (? , ?*) -->3 (n , ?*) singlet-triplet intersystem crossing will be emphasized. Currently under investigation is whether such a dissociation can be treated as an effective source of the neutral substituent. This material is based upon work supported by the National Science Foundation under Grant No. PHY-0355235.

  2. Black Smokers

    NSDL National Science Digital Library

    Svitil, Kathy A.

    This brief web article features black smokers and discusses the history of their discovery, the geologic processes creating black smokers, and the various life forms inhabiting this extreme environment. As part of the PBS "Savage Earth" series, the site contains animations of basic geologic processes, QuickTime videos and additional web articles discussing the ring of fire, the Kola well in Russia, the internal structure of the Earth, earthquakes, volcanoes, and tsunamis. This website also provides a link to the PBS home, where other PBS online programs can be found. The QuickTime program is required to view the videos and can be downloaded free of charge on site.

  3. Slip casting and nitridation of silicon powder

    NASA Technical Reports Server (NTRS)

    Seiko, Y.

    1985-01-01

    Powdered Silicon was slip-cast with a CaSO4 x 0.5H2O mold and nitrided in a N atm. containing 0 or 5 vol. % H at 1000 to 1420 deg. To remove the castings, the modeling faces were coated successively with an aq. salt soap and powdered cellulose containing Na alginate, and thus prevented the sticking problem.

  4. In-line powder coating of pultrusions

    SciTech Connect

    Spoo, K. [Owens-Corning, Granville, OH (United States); Smith, G. [Owens-Corning, Hazleton, PA (United States)

    1996-11-01

    This paper discusses the pros and cons of an in-line powder coating process that applies an acrylic modified polyurethane powder to pultruded window lineals. The system applies the finish to the pultruded part downstream from the pultrusion die. Capital costs, direct costs, and mechanics of the process are discussed.

  5. Electrical Resistivity of Metal Powder Aggregates

    Microsoft Academic Search

    J. M. Montes; F. G. Cuevas; J. Cintas

    2007-01-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles, has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system to an equivalent

  6. Numerical Simulation of Aerated Powder Consolidation1

    E-print Network

    will slowly escape by diffusing through the material. The corresponding uneven gas pressure distribution properties. Over time the excess air diffuses through the powder and eventually escapes through the top systems for the vertical conical bunker. The height of the column of powder of time is denoted

  7. Process for the synthesis of iron powder

    Microsoft Academic Search

    Welbon

    1983-01-01

    A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide

  8. Autoclave heat treatment for prealloyed powder products

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Ashbrook, R. L.

    1973-01-01

    Technique could be applied directly to loose powders as part of hot pressing process of forming them to any required shapes. This would eliminate initial extrusion step commonly applied to prealloyed powders, substantially reduce cost of forming operation, and result in optimum properties.

  9. Modeling of microwave heating of metallic powders

    Microsoft Academic Search

    V. D. Buchelnikov; D. V. Louzguine-Luzgin; A. P. Anzulevich; I. V. Bychkov; N. Yoshikawa; M. Sato; A. Inoue

    2008-01-01

    As it is known from the experiment that bulk metallic samples reflect microwaves while powdered samples can absorb such a radiation and be heated efficiently. In the present paper we investigate theoretically the mechanisms of penetration of a layer of metallic powder by microwave radiation and microwave heating of such a system.

  10. Microwave heating of conductive powder materials

    Microsoft Academic Search

    K. I. Rybakov; V. E. Semenov; S. V. Egorov; A. G. Eremeev; I. V. Plotnikov; Yu. V. Bykov

    2006-01-01

    In recent years, a considerable interest has been drawn to microwave heating of powder metals and other electrically conductive materials. In this paper a consistent formulation describing the absorption of microwaves in electrically conductive materials under different microwave heating conditions is developed. A special case when conductive powder particles are surrounded by insulating oxide layers is investigated in detail using

  11. Thermal plasma chemical synthesis of powders

    SciTech Connect

    Vogt, G.J.; Newkirk, L.R.

    1985-01-01

    Thermal plasma processing has been increasingly used to synthesize submicron powders of high-purity ceramics and metals. The high temperatures generated with the plasma provide a vapor phase reaction zone for elements with high boiling points and refractory materials. An overview is presented on the general plasma technology used in synthesis and on the properties of plasma powders.

  12. Modeling nonelectrostatic and electrostatic powder coating

    Microsoft Academic Search

    Shantanu Yousuf; Sheryl A. Barringer

    2007-01-01

    The effect of particle size, density, charge and air velocity on transfer efficiency, evenness and separation of mixtures during powder coating was investigated using modeling and experimentation. Electrostatic and nonelectrostatic coating was tested using 28, 234 and 342?m NaCl and 195?m starch powders. Transfer efficiency increased as particle size, density or charge increased or as air velocity decreased. Evenness increased

  13. Physical and dielectric properties of pharmaceutical powders

    Microsoft Academic Search

    C. M McLoughlin; W. A. M McMinn; T. R. A Magee

    2003-01-01

    The limited availability of published physical and dielectric property data for pharmaceutical powders hinders the design of processing systems, particularly dryers. In this study, the physical properties (solubility and boiling point) and dielectric properties, in terms of temperature rise, dielectric constant, and dielectric loss factor, of selected pharmaceutical powders were measured. The pharmaceutical actives, paracetamol and aspirin, and selected common

  14. Powder Metallurgy Composite Materials Strengthened with Fibers

    Microsoft Academic Search

    Suren G. Agbalyan

    2001-01-01

    The extrusion dynamics of high-strength powder metallurgy composite materials was studied. The extrusion parameters for porous compacts of copper fibers and Cu ? Mo composites were optimized. It was shown that orientation of fibers is possible only when they are sufficiently widely dispersed in the powder matrix and also when the fiber length is much greater than its diameter l

  15. Insolubility of milk powder products A minireview

    E-print Network

    Boyer, Edmond

    of milk, at the beginning of the evaporation process, the whey proteins change their conformationReview Insolubility of milk powder products A minireview Alan J. BALDWIN* Fonterra Research Abstract In this paper, the formation of insolubility in milk powder is described, and the factors

  16. Wet powder seal for gas containment

    DOEpatents

    Stang, Louis G. (Sayville, NY)

    1982-01-01

    A gas seal is formed by a compact layer of an insoluble powder and liquid filling the fine interstices of that layer. The smaller the particle size of the selected powder, such as sand or talc, the finer will be the interstices or capillary spaces in the layer and the greater will be the resulting sealing capacity, i.e., the gas pressure differential which the wet powder layer can withstand. Such wet powder seal is useful in constructing underground gas reservoirs or storage cavities for nuclear wastes as well as stopping leaks in gas mains buried under ground or situated under water. The sealing capacity of the wet powder seal can be augmented by the hydrostatic head of a liquid body established over the seal.

  17. Nanostructured GGG powders via gel combustion

    NASA Astrophysics Data System (ADS)

    Li, Xianxue; Hu, Zhang-Gui; Li, Jiangtao

    2007-03-01

    Polycrystalline nano-sized gadolinium gallium garnet (Gd3Ga5O12, GGG) powders were synthesized via a gel combustion method from a mixed solution of Ga(NO3)3, Gd(NO3)3 and citric acid. The evolution of phase composition and micro-structure of the powders were characterized by X-ray powder diffraction, thermogravimetry/differential thermal analysis and scanning electron microscopy. Well-crystallized, single phase GGG nano-sized powders could be obtained at the calcining temperature as low as 750 C for 2 h. No any intermediate phases formed during the calcining process. The resulting powders were well dispersed and had a relatively narrow size distribution with an average particle size of approximately 30-50 nm.

  18. Dense silica coatings on ceramic powder particles

    SciTech Connect

    Opitz, J.F.A.; Mayr, W. [Philips GmbH Forschungslaboratorien, Aachen (Germany)

    1995-09-01

    Dense silica coatings on the surface of inorganic powders particles are prepared by the hydrolysis of tetraethoxysilane (TEOS) in alcoholic suspensions. In a first reaction step, the TEOS is pre-hydrolysed in acidic solution and afterwards, a suspension of powder particles in this reaction solution is treated with ammonia which results in a dense silica coating of typically 10 - 100 nm thickness. Different luminescent powders which are used in the manufacture of cathode-ray tubes or fluorescent lamps have been coated by this procedure. The silica coating forms a transparent layer and the suspension properties of the coated powders are determined by the silica layer. The silica coating also protects sulfidic luminescent powders from being attacked by oxidizing agents like dichromate ions which are used in the suspension formulations for TV tube fabrication.

  19. Black Sheep

    Microsoft Academic Search

    Charles Darwin

    1880-01-01

    THE following extract of a letter from Mr. Sanderson of Chislehurst, who permits me to publish it, seems worth placing on record. It relates to the former frequent appearance of spotted or black sheep in the Australian flocks, as long as animals thus coloured were of use to man, although they were never, as far as Mr. Sanderson knows, separately

  20. Black English.

    ERIC Educational Resources Information Center

    Bailey, Charles-James N.

    This paper, presented as part of a military lecture series given by the Division of Continuing Education and Community Service Speakers' Bureau of the University of Hawaii to military personnel at Schofield Barracks and Fort Shafter, investigates the origins and present status of Black English. A discussion of early studies in the Gullah dialect

  1. Black Money

    Microsoft Academic Search

    2012-01-01

    The objective of this paper is to place in the public domain various facets and dimensions of black money and its complex relationship with the policy and administrative regime in the country. The paper also presents the framework, policy options, and strategies that the Government of India has been pursuing to tackle this issue, especially recent initiatives and developments. The

  2. Black Flies

    NSDL National Science Digital Library

    0000-00-00

    Information about the common annoyance pest the Black Fly. The flies life cycle and control strategy are covered. While the information is specific to Los Angeles California, the same strategies are effective elsewhere. Personal protection information is also offered and is universally effective.

  3. Protein Inhalation Powders: Spray Drying vs Spray Freeze Drying

    Microsoft Academic Search

    Yuh-Fun Maa; Phuong-Anh Nguyen; Theresa Sweeney; Steven J. Shire; Chung C. Hsu

    1999-01-01

    Purpose. To develop a new technique, spray freeze drying, for preparing protein aerosol powders. Also, to compare the spray freeze-dried powders with spray-dried powders in terms of physical properties and aerosol performance.

  4. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  5. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  6. 21 CFR 524.1005 - Furazolidone aerosol powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...false Furazolidone aerosol powder. 524.1005 Section 524...1005 Furazolidone aerosol powder. (a) Specifications...affected area and apply only enough powder to impart a light yellow color...lacerations, and following firing (heat or electrocautery)....

  7. 30 CFR 75.1101-18 - Dry powder requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Resources 1 2010-07-01 2010-07-01 false Dry powder requirements. 75.1101-18 Section...COAL MINES Fire Protection 75.1101-18 Dry powder requirements. Each dry powder chemical system shall contain the...

  8. 30 CFR 75.1101-18 - Dry powder requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Resources 1 2011-07-01 2011-07-01 false Dry powder requirements. 75.1101-18 Section...COAL MINES Fire Protection 75.1101-18 Dry powder requirements. Each dry powder chemical system shall contain the...

  9. Washing powders and the environment: has TAED any influence on the complexing behaviour of phosphonic acids?

    PubMed

    Deluchat, Vronique; Lacour, Stella; Serpaud, Bernard; Bollinger, Jean-Claude

    2002-10-01

    Complexation properties of two phosphonic acids: nitrilotris (methylenephosphonic acid) and 1-hydroxyethane-1,1'-diphosphonic acid, with Cu(II) and Ca(II) have been previously determined by pH and ionic selective electrode titrations. These phosphonic acids are commonly added to washing powders as polyphosphate substitutes and are here studied in the presence of another detergent compound: tetraacetylethylenediamine (TAED), a bleaching activator. Product concentrations were chosen in order to correspond to component concentration ratios encountered in washing powders. Potentiometric titrations were carried out to determine the possible TAED interferences; they indicate that TAED and its by-products have no action on phosphonic acid complexing behaviour. Under our experimental conditions, the action of TAED was modelled with acetic acid and ethylenediamine, the final by-products of TAED hydrolysis. If we take into account both phosphonic and acetic acids, speciation diagrams corresponding to representative fresh water systems showed that the acetic acid does not influence cation speciation. PMID:12420935

  10. Synthesis and characterization of magnesium substituted biphasic mixtures of controlled hydroxyapatite/{beta}-tricalcium phosphate ratios

    SciTech Connect

    Kannan, S. [Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, 3810-193 Aveiro (Portugal); Lemos, I.A.F. [Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, 3810-193 Aveiro (Portugal); Rocha, J.H.G. [Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, 3810-193 Aveiro (Portugal); Ferreira, J.M.F. [Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, 3810-193 Aveiro (Portugal)]. E-mail: jmf@cv.ua.pt

    2005-10-15

    The present paper investigates the preparation of magnesium (Mg) substituted biphasic mixtures of different hydroxyapatite (HAP)/{beta}-tricalcium phosphate ({beta}-TCP) ratios through aqueous precipitation method. The concentrations of added magnesium (Mg) were varied with the calcium in order to obtain constant (Ca+Mg)/P ratios of 1.67 ranging from 1.62+0.05, 1.58+0.09 and 1.54+0.13, respectively. The as prepared powders were calcined at different temperatures to study the phase behaviour and thermal stability. The powders were characterized by the following analytical techniques: TG-DTA, X-ray diffraction and FT-IR. The results have shown that substitution of Mg in the calcium-deficient apatites resulted in the formation of biphasic mixtures of different HAP/{beta}-TCP ratios after heating above 700 deg. C. The ratios of the formation of phase mixtures were dependent on the calcium deficiency in the apatites with the higher deficiency having the strongest impact on the increased formation of {beta}-TCP and the substituted Mg was found to stabilize the {beta}-TCP phase. - Graphical abstract: Role of Mg in the behaviour of calcium-deficient apatites during calcination to form biphasic mixtures.

  11. Effect of aluminum substitution on structural and electromagnetic properties of nanocrystalline MgCuMn ferrites

    NASA Astrophysics Data System (ADS)

    Ramesh, T.; Kumar, S. Senthil; Shinde, R. S.; Murthy, S. R.

    2015-06-01

    The effect of substitution of nonmagnetic Al3+ ions on the structural and electromagnetic properties were studied in nanocrystalline ferrite series of Mg0.8Cu0.2AlxFe1.95-xMn0.05O4 where x varies 0-0.4 in steps of 0.1. This series was synthesized by using microwave hydrothermal method. The nanocrystalline ferrite phase was observed at temperature 150C/40 min. Synthesized powders were characterized using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The synthesized powders were densified using microwave sintering method at 950C/40 min. The sintered samples were characterized using XRD. Surface morphology was observed by using field effective scanning electron microscopy (FESEM). The electrical and magnetic properties were measured at room temperature. These results led us to interfere that the values of d.c resistivity increases and dielectric constant, initial permeability, saturation magnetization and Curie temperature were observed to be decreased with the substitution of Al3+ ions with those of Fe3+. The low dielectric and magnetic losses and low magnetization exhibited by aluminum substituted MgCuMn ferrites makes them find applications in microwave devices.

  12. Powder neutron diffraction of Nd 3Co 13-xNi xB 2 compounds

    NASA Astrophysics Data System (ADS)

    Plugaru, N.; Rubn, J.; Bartolom, J.; Campo, J.; Cuello, G. J.; Tovar, M.; Prokhnenko, O.

    2007-09-01

    We report results of a powder neutron diffraction study on the crystal structure and local magnetic moments in Nd 3Co 13-xNi xB 2 compounds with Nd 3Ni 13B 2-type structure. The largest 3d magnetic moment resides at the 4 h sites. Nd magnetic moment is reduced with respect to the free ion value. Preferential Ni substitution for Co is also found at the 4h site. The refined magnetization direction is consistent with the T- x phase diagram derived from magnetization data.

  13. Deagglomeration of dry powder pharmaceutical aerosols.

    PubMed

    Voss, Austin; Finlay, Warren H

    2002-11-01

    The effect of turbulence and mechanical impaction on dry powder aerosol deaggregation was tested using a novel powder deagglomeration rig, with fine particle fraction (FPF(ED<5.6 microm)), defined here as particles sized smaller than 5.6 microm, measured using an Anderson inertial impactor. Powder from GlaxoSmithKline Ventodisks was deaggregated either using turbulence generated with a ring of impinging jets, or by impacting the powder on bars of a wire mesh. This deaggregation was compared with deaggregation achieved with the GlaxoSmithKline Diskhaler. The turbulence levels in the test rig and at the exit of the Diskhaler were quantified using laser Doppler velocimetry (LDV). In addition, the Ventodisk powder's auto-adhesion properties were altered by introducing the powder into a high humidity environment (25 degrees C and 25% R.H.) and then deagglomerated by both the rig (using turbulence as the primary deagglomeration mechanism) and the Diskhaler. Fine particle fractions were found to increase from 13 to 24% as the level of turbulence in the rig was increased. However, fine particle fractions found with the Diskhaler were 35%. Turbulence levels found in the rig at the highest jet flow rate were significantly higher than that at the outlet of the Diskhaler, leading to the conclusion that turbulence is not the only method of deaggregation in this inhaler. The humidified powders were significantly more difficult to deaggregate, giving a FPF(ED<5.6 microm) of 9% when using the rig and 15% when using the Diskhaler. Fine particle fractions produced when deagglomerating the powder with the wire meshes were similar to those produced without a mesh, showing that mechanical impaction had little effect. The results underline the utility of having a rig that can explore the ability of a powder to deagglomerate with controlled variations in the deaggregation forces. PMID:12429458

  14. X-ray data for the substitutional solid solution of the binary system ammonium dihydrogen phosphate with boric acid

    Microsoft Academic Search

    M. L. N. Madhu Mohan; C. Haranadh

    1994-01-01

    X-ray powder diffraction data for the binary system ammonium dihydrogen phosphate with boric acid is studied and it is inferred\\u000a that the binary belongs to tetragonal system and forms a substitutional solid phase. On the basis of the space group the binary\\u000a is predicted to exhibit electrooptic property along with piezoelectric and electrostriction properties. It is proposed that\\u000a the phosphorus

  15. Effect of La 3+ substitution on the structural, electrical and electrochemical properties of strontium ferrite by citrate combustion method

    Microsoft Academic Search

    C. O. Augustin; R. Kalai Selvan; R. Nagaraj; L. John Berchmans

    2005-01-01

    The La3+ substituted nanocrystalline strontium ferrite has been prepared by citrate combustion method using metal nitrate salts as cation precursors and citric acid as a fuel. The structural characteristics of the compounds have been evaluated using XRD and FTIR. The existence of the single-phase perovskite structure with nanocrystalline size has been confirmed from the X-ray powder diffraction patterns. The stretching

  16. Shock compression response of nanoiron powder compact

    NASA Astrophysics Data System (ADS)

    Dai, Chengda; Eakins, Daniel; Thadhani, Naresh; Liu, J. Ping

    2007-02-01

    The shock compression response of nano-Fe powder (25nm) pressed to 35% theoretical maximum density was determined based on shock stress and wave velocity measurements using piezoelectric stress gauges. The obtained data show a discontinuity in shock wave velocity plotted against particle velocity and an inflexion in specific volume from compression to expansion with increasing shock stress. It is found that the Hugoniot of 25nm Fe powder cannot be fully described using analytical models that are otherwise capable of predicting the Hugoniot of micron-sized powder or highly porous materials.

  17. Electrical Resistivity of Metal Powder Aggregates

    NASA Astrophysics Data System (ADS)

    Montes, J. M.; Cuevas, F. G.; Cintas, J.

    2007-12-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles, has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system to an equivalent system consisting of deforming spheres in a simple cubic packing, which is much easier to examine. The proposed equation was experimentally verified from measurements of the electrical resistivity for aluminum, bronze, iron, and nickel powders under pressure. The consistency between theoretical predictions and experimental results was reasonably good in all cases.

  18. Microwave heating of conductive powder materials

    NASA Astrophysics Data System (ADS)

    Rybakov, K. I.; Semenov, V. E.; Egorov, S. V.; Eremeev, A. G.; Plotnikov, I. V.; Bykov, Yu. V.

    2006-01-01

    In recent years, a considerable interest has been drawn to microwave heating of powder metals and other electrically conductive materials. In this paper a consistent formulation describing the absorption of microwaves in electrically conductive materials under different microwave heating conditions is developed. A special case when conductive powder particles are surrounded by insulating oxide layers is investigated in detail using the effective-medium approximation. The conditions giving rise to skin effect governed, volumetric, and localized microwave heating are analyzed. Experimental observations of different microwave heating regimes in silicon, iron, and copper powder compacts are in general agreement with the theoretical model.

  19. Pulmonary drug delivery by powder aerosols.

    PubMed

    Yang, Michael Yifei; Chan, John Gar Yan; Chan, Hak-Kim

    2014-11-10

    The efficacy of pharmaceutical aerosols relates to its deposition in the clinically relevant regions of the lungs, which can be assessed by in vivo lung deposition studies. Dry powder formulations are popular as devices are portable and aerosolisation does not require a propellant. Over the years, key advancements in dry powder formulation, device design and our understanding on the mechanics of inhaled pharmaceutical aerosol have opened up new opportunities in treatment of diseases through pulmonary drug delivery. This review covers these advancements and future directions for inhaled dry powder aerosols. PMID:24818765

  20. Analysis of powder diffraction data

    SciTech Connect

    Cooper, M.J.

    1982-01-01

    A comparison has been carried out between the results of analyses of several sets of neutron powder diffraction data using three different methods: the Rietveld method (H.M. Rietveld, Acta. Cryst. 2, 151-152 (1967): J. Appl. Cryst. 2, 65-71 (1969), a modification of the Rietveld method to include off-diagonal terms in the weight matrix (C.P. Clarke and J.S. Rollett, Acta. Cryst. In the press) and the SCRAP method, which involves the estimation of observed Bragg intensities (M.J. Cooper, K.D. Rouse and M. Sakata, Z. Krist. In the press). Two simulations have also been carried out to demonstrate the way in which the results can differ in more extreme cases. This study has confirmed that the values of the estimated standard deviations given by the Rietveld method are not reliable and that, of the methods considered, only the SCRAP method will in general give reliable values for the estimated standard deviations of the structural parameters.

  1. Continuous production of titanium powder

    SciTech Connect

    Gerdemann, Stephen J.; Oden, Laurence L.; White, Jack C.

    1997-01-01

    Although incremental improvements have been made to the Kroll process since its inception in 1948, the process in use today remains essentially the same batch process developed by Dr. Kroll and perfected by the U.S. Bureau of Mines. In this process, titanium tetrachloride (TiCl4) is reduced by magnesium to produce titanium metal. There are two major limitations to the Kroll process: (1) it is a batch process; and (2) the reduction of TiCl4 proceeds so rapidly that the sponge formed is an interlocking dendritic mass with inclusions of magnesium, magnesium salts and titanium subchloride that must undergo several purification steps before the metal is suitable for use. The Albany Research Center (ARC), formerly the U.S. Bureau of Mines, has investigated a new, continuous titanium metal production process in which a titanium powder is produced in a bath of molten salt. In this process, the rate of the reduction reaction was slowed and controlled by diluting the reactants with molten chloride salts. The diluted reactant streams were combined in a continuous stirred tank reactor, operated much like a crystallizer. New titanium metal forms on the already present small Ti particles. When the Ti particles become too large to remain suspended in solution, they fall to the bottom of the reactor and are removed. Initial experiments show promise but problems remain in obtaining the required purity and uniform particle size.

  2. Development of latent fingerprints on a nonporous surface, using standard brushing method for powders: second collaborative study.

    PubMed

    Connor, C M

    1975-01-01

    Twelve latent fingerprint examiners participated in a collaborative study of a modification of the official first action powder brushing method for the development of latent fingerprints. Latent images were placed on glass slides by the examiners, using male and femal subjects. The standard brushing method, using black, copper, and gray powders provided by the Associate Referee, was used to develop the fingerprints at various times up to 120 hr after the images were placed on the slides. Conclusive results were obtained: 139 of the 160 images (86.9%) were considered suitable for identification purposes. The method has been adopted as official final action. PMID:1141147

  3. Laminated composite of magnetic alloy powder and ceramic powder and process for making same

    DOEpatents

    Moorhead, Arthur J. (Knoxville, TN); Kim, Hyoun-Ee (Seoul, KR)

    1999-01-01

    A laminated composite structure of alternating metal powder layers, and layers formed of an inorganic bonding media powder, and a method for manufacturing same are discosed. The method includes the steps of assembling in a cavity alternating layers of a metal powder and an inorganic bonding media of a ceramic, glass, and glass-ceramic. Heat, with or without pressure, is applied to the alternating layers until the particles of the metal powder are sintered together and bonded into the laminated composite structure by the layers of sintered inorganic bonding media to form a strong composite structure. The method finds particular application in the manufacture of high performance magnets wherein the metal powder is a magnetic alloy powder.

  4. Smoking Cessation among Blacks.

    ERIC Educational Resources Information Center

    Stotts, R. Craig; And Others

    1991-01-01

    Lung cancer is a serious health problem among blacks, with a mortality rate of 119 per 100,000 black males, compared to 81 per 100,000 for white males. Smoking cessation efforts are most successful when tailored to the black community, using black community networks and broadcast media for black audiences. (SLD)

  5. Black Women and Feminism

    Microsoft Academic Search

    Clyde Wilcox

    1990-01-01

    Little research to date has examined the attitudes of black women toward feminism, primarily because few national surveys contain sufficient numbers of black women to take meaningful generalizations. Using data from a national survey of blacks in 1980, this study explores the levels and determinants of feminism among black women. The results show strong support for feminism among black women,

  6. Effects of milk powders in milk chocolate.

    PubMed

    Liang, B; Hartel, R W

    2004-01-01

    The physical characteristics of milk powders used in chocolate can have significant impact on the processing conditions needed to make that chocolate and the physical and organoleptic properties of the finished product. Four milk powders with different particle characteristics (size, shape, density) and "free" milk fat levels (easily extracted with organic solvent) were evaluated for their effect on the processing conditions and characteristics of chocolates in which they were used. Many aspects of chocolate manufacture and storage (tempering conditions, melt rheology, hardness, bloom stability) were dependent on the level of free milk fat in the milk powder. However, particle characteristics of the milk powder also influenced the physical and sensory properties of the final products. PMID:14765806

  7. Screening and classification of ceramic powders

    NASA Technical Reports Server (NTRS)

    Miwa, S.

    1983-01-01

    A summary is given of the classification technology of ceramic powders. Advantages and disadvantages of the wet and dry screening and classification methods are discussed. Improvements of wind force screening devices are described.

  8. Magnesium Powder Metallurgy: Process and Materials Opportunities

    NASA Astrophysics Data System (ADS)

    Bettles, Colleen J.

    2008-06-01

    The major efforts in magnesium alloy development for automotive applications have concentrated on creep resistant alloys produced by permanent mould and high-pressure die casting routes. While large components, such as crankcases, will never be produced by powder metallurgy, there are smaller components in and around the powertrain which could be fabricated from powder precursors. This article will explore the potential of some of the more recent powder compaction developments, and discuss the alloy development strategies that emerge for magnesium-based components as a consequence of these process developments. In particular, the viability of direct powder extrusion of semi-finished product, using conventional extrusion or equal channel angular processing, combined with T6 heat treatments, will be considered.

  9. Advances in beryllium powder consolidation simulation

    SciTech Connect

    Reardon, B.J.

    1998-12-01

    A fuzzy logic based multiobjective genetic algorithm (GA) is introduced and the algorithm is used to optimize micromechanical densification modeling parameters for warm isopressed beryllium powder, HIPed copper powder and CIPed/sintered and HIPed tantalum powder. In addition to optimizing the main model parameters using the experimental data points as objective functions, the GA provides a quantitative measure of the sensitivity of the model to each parameter, estimates the mean particle size of the powder, and determines the smoothing factors for the transition between stage 1 and stage 2 densification. While the GA does not provide a sensitivity analysis in the strictest sense, and is highly stochastic in nature, this method is reliable and reproducible in optimizing parameters given any size data set and determining the impact on the model of slight variations in each parameter.

  10. Synthesis of La-Co Substituted M-type Calcium Hexaferrite by Polymerizable Complex Method

    NASA Astrophysics Data System (ADS)

    Kikuchi, T.; Nakamura, T.; Yamasaki, T.; Nakanishi, M.; Fujii, T.; Takada, J.; Ikeda, Y.

    2011-10-01

    Synthesis of La-Co substituted M-type Calcium hexaferrite was studied. Samples were prepared by polymerizable complex method. High purity reagent of strontium carbonate, iron (III) nitrate ennnahydrate, cobalt (II) nitrate hexahydrate and lanthanum oxide were used as starting materials. Prepared aqueous solution was heated for dehydration and gelling. Thermal pyrolysis was carried out by heating the gel. The obtained precursor powders were ground with an alumina mortar and compacted by uniaxial pressing into disk specimens and then heated at temperature range between 1173 K and 1573 K in air. Phase identification and determination of lattice parameters were carried out by powder X-ray diffraction (XRD). Scanning Electron Microscope (SEM) was utilized to investigate the microstructure of the polycrystalline ferrites. Magnetic properties were discussed by magnetization measurements by measuring of M-H curve with vibrating sample magnetometer (VSM). Single-phase of M-type hexaferrite was obtained at lower temperature relative to by conventional synthesis.

  11. The basics of powder lubrication in high-temperature powder-lubricated dampers

    Microsoft Academic Search

    H. Heshmat; J. F. Walton

    1993-01-01

    The objective of this investigation is to develop a novel powder-lubricated rotor bearing system damper concept for use in high-temperature, high-speed rotating machinery such as advanced aircraft gas turbine engines. The approach discussed herein consists of replacing a conventional oil lubrication or frictional damper system with a powder lubrication system that uses the process particulates or externally fed powder lubricant.

  12. [Use of powder metallurgy for development of implants of Co-Cr-Mo alloy powder].

    PubMed

    Dabrowski, J R

    2001-04-01

    This paper discusses the application of powder metallurgy for the development of porous implantation materials. Powders obtained from Co-Cr-Mo alloy with different carbon content by water spraying and grinding, have been investigated. Cold pressing and rotary re-pressing methods were used for compressing the powder. It was found that the sintered materials obtained from water spraying have the most advantageous properties. PMID:11388037

  13. Research of minimum ignition energy for nano Titanium powder and nano Iron powder

    Microsoft Academic Search

    Hong-Chun Wu; Ri-Cheng Chang; Hsiao-Chi Hsiao

    2009-01-01

    Most manufacturing units that process nanoparticles face a threat from fires and explosions. This study examines Ti powders with diameters of 3?m, 8?m, 20?m, 45?m, 35nm, 75nm, and 100nm, and Fe powders with diameters of 150?m, 15nm, 35nm, and 65nm. The goal of our study was to measure the minimum ignition energy (MIE) for each of the above mentioned powders

  14. Fine PMN powders prepared from nitrate solutions

    Microsoft Academic Search

    Y. Yoshikawa

    1994-01-01

    A partial coprecipitation method was developed in order to synthesize lead magnesium niobate Pb(Mg1\\/3Nb(2\\/3))O3 (PMN) powders from nitrate solutions. To obtain a niobium precursor compatible with the chemical routes, peroxo-niobium complex solutions were prepared by dissolving hydrated niobia precipitates in a dilute nitric acid solution with hydrogen peroxide. Fine PMN powders were prepared from these nitrate solutions by two-stage hydrolysis.

  15. Relative flow rates of explosive powders

    SciTech Connect

    Willson, V.P.

    1988-05-31

    A study was performed to determine the relative flow rates of various explosive powders and evaluate their adaptability for use in automated dispensing systems. Results showed that PBX 9407, LX-15, RX-26-BH, and HNAB are potential candidates for use in these systems. It was also shown that powders with graphite and stearate additives generated the least amount of static and were the easiest to handle.

  16. Microemulsion Synthesis of Nanoparticle PZT Powder

    Microsoft Academic Search

    M. Amiriyan; Z. A. Nemati; M. S. Rahmanifar; S. Ramesh; S. Meenaloshini; R. Tolouei

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325

  17. Synthesis and processing of monosized oxide powders

    DOEpatents

    Barringer, E.A.; Fegley, M.B. Jr.; Bowen, H.K.

    1985-09-24

    Uniform-size, high-purity, spherical oxide powders are formed by hydrolysis of alkoxide precursors in dilute alcoholic solutions. Under controlled conditions (concentrations of 0.03 to 0.2 M alkoxide and 0.2 to 1.5 M water, for example) oxide particles on the order of about 0.05 to 0.7 microns can be produced. Methods of doping such powders and forming sinterable compacts are also disclosed. 6 figs.

  18. Synthesis and processing of monosized oxide powders

    DOEpatents

    Barringer, Eric A. (Waltham, MA); Fegley, Jr., M. Bruce (Waban, MA); Bowen, H. Kent (Belmont, MA)

    1985-01-01

    Uniform-size, high-purity, spherical oxide powders are formed by hydrolysis of alkoxide precursors in dilute alcoholic solutions. Under controlled conditions (concentrations of 0.03 to 0.2 M alkoxide and 0.2 to 1.5 M water, for example) oxide particles on the order of about 0.05 to 0.7 micron can be produced. Methods of doping such powders and forming sinterable compacts are also disclosed.

  19. Electrical Resistivity of Metal Powder Aggregates

    Microsoft Academic Search

    J. M. Montes; F. G. Cuevas; J. Cintas

    2007-01-01

    An equation for calculating the electrical resistivity of a compressed powder mass, consisting of oxide-coated metal particles,\\u000a has been derived. In addition to the intrinsic interest of the problem, the proposed equation is useful for describing the\\u000a very early stages of electrical sintering processes. The problem is approached in a new way, relating the actual powder system\\u000a to an equivalent

  20. Adjustable Powder Injector For Vacuum Plasma Sprayer

    NASA Technical Reports Server (NTRS)

    Burns, D. H.; Woodford, W. H.; Mckechnie, T. N.; Mcferrin, D. C.; Davis, W. M.; Beason, G. P., Jr.

    1993-01-01

    Attachment for plasma spray gun provides four degrees of freedom for adjustment of position and orientation at which powder injected externally into plasma flame. Manipulator provides for adjustment of pitch angle of injection tube: set to inject powder at any angle ranging from perpendicular to parallel to cylindrical axis. Scribed lines on extension bar and manipulator indicate pitch angle of extension tube. Collar changed to adapt injector to different gun.

  1. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1994-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used

  2. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1994-01-01

    A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be

  3. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1992-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can

  4. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1993-01-01

    Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can

  5. Dry powder mixes comprising phase change materials

    Microsoft Academic Search

    Salyer; Ival O

    1995-01-01

    A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be

  6. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit (Knoxville, TN); Williams, Robert K. (Knoxville, TN)

    2001-01-01

    A biaxially textured alloy article comprises Ni powder and at least one powder selected from the group consisting of Cr, W, V, Mo, Cu, Al, Ce, YSZ, Y, Rare Earths, (RE), MgO, CeO.sub.2, and Y.sub.2 O.sub.3 ; compacted and heat treated, then rapidly recrystallized to produce a biaxial texture on the article. In some embodiments the alloy article further comprises electromagnetic or electro-optical devices and possesses superconducting properties.

  7. Microemulsion Synthesis of Nanoparticle PZT Powder

    NASA Astrophysics Data System (ADS)

    Amiriyan, M.; Nemati, Z. A.; Rahmanifar, M. S.; Ramesh, S.; Meenaloshini, S.; Tolouei, R.

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325 M Zr4+, and 0.3 M Ti4+, representing a Pb2+: Zr4+: Ti4+ molar ratio of 1:0.52:0.48. The ratio of these cations has been adjusted using Inductively Coupled Plasma (ICP) technique. After coprecipitation of metallic hydroxides by adding ammonia solution in microemulsion system, the PZT precursor was obtained. PZT powders have been prepared upon calcination of precursor at 800 C. Prepared powders was characterised using techniques such as X-ray diffraction, differential thermal analysis, and scanning electron microscopy. The characteristics of microemulsion processed powder is discussed, with emphasis on the presence of nano scaled PZT powder with a composition near to morphotropic phase boundary (MPB) without formation of any intermediate phases.

  8. Ti Multicomponent Alloy Bulks by Powder Metallurgy

    NASA Astrophysics Data System (ADS)

    Zhang, Kuibao; Wen, Guanjun; Dai, Hongchuan; Teng, Yuancheng; Li, Yuxiang

    2014-10-01

    In this study, CrCuFeMnMo0.5Ti multicomponent alloy bulks were prepared by powder metallurgy of mechanical alloying and sintering. A simple body-centered cubic (bcc) solid solution was prepared after 40 h ball milling of the raw CrCuFeMnMo0.5Ti metallic powder. Particles of the alloyed powder are in microsized structures, which are actually a soft agglomeration of lamellar grains with thicknesses less than 1 ?m. Meanwhile, the lamellar granules are consisted of nanosized grains under rigid cold welding. The 80-h ball-milled powder was consolidated by cold pressing and subsequent sintering at 800C. The observed main phase in the consolidated sample after milling for 80 h is still a bcc solid solution. The solidified sample of 80-h ball-milled powder exhibits a Vickers hardness of 468 HV, which is much higher than 171 HV of the counterpart prepared from the raw metallic powder.

  9. Cation distribution by Rietveld, spectral and magnetic studies of chromium-substituted nickel ferrites

    NASA Astrophysics Data System (ADS)

    Patange, S. M.; Shirsath, Sagar E.; Toksha, B. G.; Jadhav, S. S.; Shukla, S. J.; Jadhav, K. M.

    2009-05-01

    Ultrafine crystals of chromium-substituted nickel ferrite were prepared by wet chemical co-precipitation method using sulphates of respective metal ions. Formation of these materials has been confirmed by X-ray powder diffraction method. The fine crystal nature of these materials is evidenced from scanning electron microscope (SEM). Cation distribution has been investigated using X-ray diffraction technique. Cation distribution indicates that chromium occupy octahedral site for all the values of composition x. The saturation magnetization and magneton number both are decreasing with increase of chromium concentration x. The decrease in saturation magnetization and magneton number is attributed to the substitution of the Cr3+ ions. Curie temperature ( T C ) from susceptibility plot is found to decrease with Cr concentration x. Curie temperature of all the compositions are also obtained theoretically and it agrees with observed Curie temperature.

  10. Synthesis, characterization and nonlinear optical properties of symmetrically substituted dibenzylideneacetone derivatives

    NASA Astrophysics Data System (ADS)

    Sunil Kumar Reddy, N.; Badam, Rajashekar; Sattibabu, Romala; Molli, Muralikrishna; Sai Muthukumar, V.; Siva Sankara Sai, S.; Rao, G. Nageswara

    2014-11-01

    We report here the nonlinear optical (NLO) properties of eight bis-chalcones of D-?-A-?-D type. These dibenzylideneacetone (DBA) derivatives are synthesized by Claisen-Schmidt reaction. The compounds are characterized by UV-vis, FTIR, 1H NMR, 13C NMR, mass spectroscopy and powder XRD. By substituting different groups (electron withdrawing and electron donating) at 'para' and 'meta' positions of the aromatic ring, we observed an enhancement in second harmonic generation with substitution at 'para' position. These compounds have also showed higher two-photon absorption compared to other chalcones reported in literature. These compounds, exhibiting both second and third order NLO effects, are plausible candidate materials in photonic devices.

  11. Aluminium substitution in iron(IIIII)-layered double hydroxides: Formation and cationic order

    Microsoft Academic Search

    Christian Ruby; Mustapha Abdelmoula; Rabha Aissa; Ghouti Medjahdi; Michela Brunelli; Michel Franois

    2008-01-01

    The formation and the modifications of the structural properties of an aluminium-substituted iron(IIIII)-layered double hydroxide (LDH) of formula Fe4IIFe(2-6y)IIIAl6yIII (OH)12 SO4, 8H2O are followed by pH titration curves, Mssbauer spectroscopy and high-resolution X-ray powder diffraction using synchrotron radiation. Rietveld refinements allow to build a structural model for hydroxysulphate green rust, GR(SO42?), i.e. y=0, in which a bilayer of sulphate anions

  12. Study on the Properties of Fe-substituted NdMn2O5

    NASA Astrophysics Data System (ADS)

    Saravana Kumar, K.; Venkateswaran, C.

    2015-02-01

    The oxide, NdFeMnO5, has been synthesized using a two-step synthesis process. First the precursor oxides are high-energy ball milled and the as-milled powders are then sintered to obtain the NdFeMnO5 phase. X-ray diffraction confirms phase formation and the calculated pattern is obtained by the substitution of Mn3+ sites by Fe3+ sites. Agglomeration of small sized grains is observed from the scanning electron microscopy images. Room temperature magnetization measurement shows a paramagnetic behaviour. A ferrimagnetic ordering is observed to be established below ~110 K from the thermo-magnetization measurements.

  13. Characteristics of vanadium-substituted mesoporous silica with wormhole framework structure: effects of vanadium content

    Microsoft Academic Search

    Wei-Jye Wang; Hsin-Yu Lin; Yu-Wen Chen

    2007-01-01

    Vanadium-substituted wormhole framework structure (V-WMS) mesoporous silicas (V-WMS) with various Si\\/V ratios in the range\\u000a of 15 and 200 were prepared at ambient temperature by neutral surfactant templating pathway. The materials were synthesized\\u000a by using dodecylamine as a template and tetraethylorthosilicate as a silicon source. They were characterized by energy dispersive\\u000a X-ray spectroscopy (EDS), powder X-ray diffraction (XRD), N2 adsorptiondesorption,

  14. Preparation and performance of hydroxypropyl methylcellulose esters of substituted succinates for in vitro supersaturation of a crystalline hydrophobic drug.

    PubMed

    Yin, Ligeng; Hillmyer, Marc A

    2014-01-01

    We prepared hydroxypropyl methylcellulose (HPMC) esters of substituted succinates and examined their performance for improving the aqueous solubility of crystalline hydrophobic drugs in spray-dried dispersions (SDDs). From one HPMC, we synthesized five HPMC esters using various monosubstituted succinic anhydrides. These HPMC esters along with a commercial HPMC acetate succinate (HPMCAS) were spray-dried from solutions with phenytoin. The SDDs with different matrices at 10 wt % loading had very similar bulk properties with a minimal amount of detectable crystalline phenytoin as revealed by scanning electron microscopy (SEM), powder X-ray diffraction (powder XRD), and differential scanning calorimetry (DSC). In solution, while the SDD with HPMCAS was very effective at achieving high levels of phenytoin supersaturation initially, it was not competent at maintaining such supersaturation due to the rapid crystallization of the dissolved phenytoin. Alternatively, SDDs with several synthesized HPMC esters of substituted succinates not only achieved rather high initial supersaturation but also maintained high concentrations for extended time (i.e., 1.5 h and longer). Such maintenance was largely ascribed to the inhibition of phenytoin nucleation. Structure-property relationships were established, and the most successful systems contained a high degree of substitution and a combination of a thioether with neighboring weak electron-withdrawing groups in the substituted succinic anhydrides. The effective maintenance of supersaturated solutions was only found in SDDs with rather low drug loadings, which indicates the significance of sufficiently high concentrations of polymer additives in the dissolution media. PMID:24320108

  15. The application of PLC in electrostatic powder sprayer

    Microsoft Academic Search

    Caiqiao Wei; Tianyan Ma; Deping Zhang

    2011-01-01

    In order to prevent the glass from scratching and mildewing in storage and transportation, the anti-mildew powder should be added between the glass. For the demand of the powder spraying , the electrostatic powder sprayer control system based on PLC was developed. Spraying constant powder for the middle -part glass of variable thickness realized by controlling two frequency converters respectively.

  16. Dispersion of alkoxide-hydrolysed zirconia powders in aqueous suspensions

    Microsoft Academic Search

    Kwang-Lung Lin; Huey-Chang Wang

    1989-01-01

    It is always desirable to control the agglomeration of ceramic powders in ceramic processing, as this strongly affects the sintering behaviour [1, 2] of the powders. A recent wet chemical process deserves attention because of the possibility of achieving ultrafine, high-purity monodispersed ceramic powders [3, 4] and the possibility of the powders obtained to yield ultrastructure [5]. During wet chemical

  17. Modelling Dry Powder Inhaler Operation with the Discrete Element

    E-print Network

    Frey, Pascal

    Modelling Dry Powder Inhaler Operation with the Discrete Element Method Robert James Tuley Powder Inhaler Operation with the Discrete Element Method Robert James Tuley Abstract Dry powder inhalers is known about their internal operation: the process of fluidising a powder dose into an inhalation airflow

  18. Lining of light metals with hard powders using shot peening

    Microsoft Academic Search

    Yasunori Harada; Ken-ichiro Mori; Seijiro Maki

    2002-01-01

    A lining of light metals with hard powders using shot peening was carried out. The hard powders are bonded to the surface of the workpieces due to the collision with many shots. To fix the hard powders on the surface of the workpiece, the powder is placed on the uneven surface, and the surface is covered with a pure aluminium

  19. January 2013 BEE CULTURE 23 Revisiting Powdered Sugar For

    E-print Network

    Delaplane, Keith S.

    January 2013 BEE CULTURE 23 Revisiting Powdered Sugar For Varroa Control On Honey Bees (Apis dust bees with powder sugar as a means of removing mites. Dusting with powder sugar was also gaining conducted a study which examined the efficacy of powder sugar and found it did not help in controlling

  20. Electromagnetic properties of samarium-substituted NiCuZn ferrite prepared by auto-combustion method

    NASA Astrophysics Data System (ADS)

    Roy, P. K.; Bera, J.

    2009-02-01

    Ni 0.25Cu 0.2Zn 0.55Sm xFe 2-xO 4 ferrite with x=0.00, 0.025, 0.05 and 0.075 compositions were synthesized through the nitrate-citrate auto-combustion method. These powders were calcined, compacted and sintered at 900 C for 4 h. Effect of Sm substitution on phase composition, microstructure and relative density were studied. Permeability, magnetic loss and AC resistivity were measured in the frequency range of 1 kHz-10 MHz. Permeability and AC resistivity were found to increase and loss decreased with Sm substitution up to x=0.05. Saturation magnetization also increased up to that substitution limit. Observed variations in electromagnetic properties have been explained.

  1. Evaluation of antioxidant, rheological, physical and sensorial properties of wheat flour dough and cake containing turmeric powder.

    PubMed

    Park, S H; Lim, H S; Hwang, S Y

    2012-10-01

    The effects of addition of turmeric powder (0%, 2%, 4%, 6% and 8%) were examined in order to obtain an antioxidant-enriched cake with good physico-chemical and sensorial properties. The rheological properties of doughs were evaluated using dynamic rheological measurements. Physical properties, curcumin content, radical scavenging activity (RSA-DPPH assay) and sensory analysis (hedonic test) of the supplemented cake were determined. Addition of turmeric powder up to 8% caused significant changes on dough characteristics and on cake rheological properties. The highest curcumin (203?mg/kg) and RSA-DPPH activity (45%) were achieved in the cake having the highest percentage of turmeric powder (8%); however, this sample showed the worst results regarding the rheological properties. Moreover, by sensory evaluation this cake sample was not acceptable. A 6% substitution of wheat flour with turmeric powder showed acceptable sensory scores which were comparable to those of 0-4% turmeric cakes. This indicated that up to 6% level of turmeric powder might be included in cake formulation. PMID:23144239

  2. X-ray and Raman spectroscopic studies on Ru substituted LiMn2O4

    NASA Astrophysics Data System (ADS)

    Kalavathi, S.; Kalaivani, D.; Ravindran, T. R.; Sahu, P. Ch.

    2015-06-01

    Phase pure Ru substituted LiMn2O4 charge frustrated spinel compounds have been synthesized. Ru substitution for Mn is possible only up to 7.5%. Powder diffraction measurements confirm sustenance of charge frustrated cubic phase with space group Fd3m upon substitution of Ru for Mn. An increase in lattice parameter has been observed indicating replacement of Mn as Ru3+ or Ru4+ rather than Ru5+. Raman spectroscopic measurements show that the crystal structure is robust against an increase of laser power and the observed bands show an expected red shift. In the case of Ru substituted LiMn2O4, the A1g symmetric stretching mode, the F(1)2g and the F(2)2g symmetric bending modes identified with the Mn-O octahedra show a red shift up to Ru 0.075 and at higher Ru concentrations, revert back to the frequency corresponding to the pristine LiMn2O4.

  3. Synthesis and Characterization of La and Nb substituted Bi4Ti3O12 ferroelectric ceramics

    NASA Astrophysics Data System (ADS)

    Roy, M.; Bala, Indu; Barbar, S. K.; Jangid, S.; Dave, P.

    2011-12-01

    Polycrystalline ceramic samples of Bi3.5La0.5Ti3-yNbyO12 (y = 0.02, 0.04, 0.06 & 0.1) have been synthesized by standard solid state reaction method. The effect of lanthanum substitution on Bi-site and Nb substitution on Ti-site on the structural and electrical properties of Bi4Ti3O12 powders was investigated by X-ray diffraction, dc conductivity and dielectric measurements. A better agreement between the observed and calculated X-ray diffraction pattern was obtained by performing the Rietveld refinement with a structural model using the non centrosymmetric space group Fmmm. The substitution of Nb for Ti ions modified the dielectric properties leading to more resistive ceramic compounds. The activation energies of all the compounds were calculated by measuring its dc electrical conductivities. The temperature dependent dielectric behavior of all the compounds have also been studied and the results are discussed in detail. The substitution of La and Nb on the Bi and Ti site decreased the Tc and improved the ferroelectric and dielectric behaviour.

  4. The osteogenic response of mesenchymal stromal cells to strontium-substituted bioactive glasses.

    PubMed

    Santocildes-Romero, Martin E; Crawford, Aileen; Hatton, Paul V; Goodchild, Rebecca L; Reaney, Ian M; Miller, Cheryl A

    2015-05-01

    Bioactive glasses are known to stimulate bone healing, and the incorporation of strontium has the potential to increase their potency. In this study, calcium oxide in the 45S5 bioactive glass composition was partially (50%, Sr50) or fully (100%, Sr100) substituted with strontium oxide on a molar basis. The effects of the substitution on bioactive glass properties were studied, including density, solubility, and in vitro cytotoxicity. Stimulation of osteogenic differentiation was investigated using mesenchymal stromal cells obtained from rat bone marrow. Strontium substitution resulted in altered physical properties including increased solubility. Statistically significant reductions in cell viability were observed with the addition of bioactive glass powders to culture medium. Specifically, addition of???13.3?mg/ml of 45S5 bioactive glass or Sr50, or???6.7?mg/ml of Sr100, resulted in significant inhibition. Real-time PCR analyses detected the upregulation of genes associated with osteoblastic differentiation in the presence of all bioactive glass compositions. Some genes, including Alpl and Bglap, were further stimulated in the presence of Sr50 and Sr100. It was concluded that strontium-substituted bioactive glasses promoted osteogenesis in a differentiating bone cell culture model and, therefore, have considerable potential for use as improved bioactive glasses for bone tissue regeneration. PMID:25757935

  5. Black Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Black Sea in eastern Russia is experiencing an ongoing phytoplankton bloom. This image, the most recent in a series that began in early may, shows the waters to be even more colorful than before. part of the increased brightness may be due to the presence of sun glint , especially in the center of the sea. However, more organisms appear to be present as well, their photosynthetic pigments reflecting different wavelengths of light.This Moderate Resolution Imaging Spectroradiometer (MODIS) image was captured on June 15, 2002.

  6. Black Smokers

    NSDL National Science Digital Library

    This webpage contains a brief introduction to the discovery of hydrothermal systems and black smokers. Within the webpage are links to information on gigantic tube worms, polychaete worms, oceans, and extreme environments. This site also provides a list of hydrothermal systems, relevant links to organizations, laboratories and observatories, WebQuests, and other websites with further information on hydrothermal systems. As part of the Environmental Literacy Council site, this webpage also contains links to other resources with environmental content, including air climate, land, water, ecosystems, energy, food, and environment and society.

  7. SIMILARITY NETWORK FOR SEMANTIC WEB SERVICES SUBSTITUTION

    E-print Network

    Paris-Sud XI, Universit de

    SIMILARITY NETWORK FOR SEMANTIC WEB SERVICES SUBSTITUTION Chantal Cherifi LE2I Laboratory, Burgundy is performed on a benchmark of semantically annotated Web services. Results show that this approach allows a more detailed analysis of substitutable Web services. Keywords - Semantic Web services, Functional

  8. A virtual substitution of Brouwer choice sequence

    E-print Network

    Klaus Lange

    2009-08-24

    Step by step a substitution of the well known Brouwer choice sequence will be constructed. It begins with an establishing of quasi alternating prime number series followed by a construction of a virtual sequence in sense of the virtual set definition. The last step gives reasons for why this virtual sequence substitutes the choice sequence created by L. E. J. Brouwer.

  9. Substitute Teachers: Making Lost Days Count

    ERIC Educational Resources Information Center

    True, Charlene; Butler, Kyle; Sefton, Rachel

    2011-01-01

    As K-12 teachers and administrators grow increasingly concerned with issues of accountability, research-based methods, and intervention strategies, little discussion exists on the impact of substitute teachers in the classroom. In the rush to analyze test scores, are the days covered by substitute teachers even considered? Though districts are

  10. PALINDROME COMPLEXITY BOUNDS FOR PRIMITIVE SUBSTITUTION SEQUENCES

    E-print Network

    PALINDROME COMPLEXITY BOUNDS FOR PRIMITIVE SUBSTITUTION SEQUENCES DAVID DAMANIK 1;2 AND DOUGLAS on the frequencies of palindromes in such words. As an application of these bounds, we prove that the strongly palindromic sequences in a primitive substitution dynamical sys­ tem form a set of measure zero. 1

  11. Palindrome complexity bounds for primitive substitution sequences

    Microsoft Academic Search

    David Damanik; Douglas Zare

    2000-01-01

    . We consider one-sided infinite words generated via iteration byprimitive substitutions on finite alphabets and provide bounds on the palindromecomplexity function as well as uniform bounds on the frequencies ofpalindromes in such words. As an application of these bounds, we prove thatthe strongly palindromic sequences in a primitive substitution dynamical systemform a set of measure zero.1. IntroductionIn this paper we

  12. Slip casting nano-particle powders for making transparent ceramics

    DOEpatents

    Kuntz, Joshua D. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Landingham, Richard Lee (Livermore, CA); Hollingsworth, Joel P. (Oakland, CA)

    2011-04-12

    A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

  13. [Prophylaxis of dental caries using sugar substitutes].

    PubMed

    Eberle, G

    1984-12-01

    Among the three measures, which are capable of producing a preventive effect against caries only when applied combined, i.e. adequate fluoride supply, proper mouth hygiene and healthy nutrition, the latter is dealt with in greater detail. The use of sugar substitutes is discussed under the aspects of caries prevention, substitute composition and production technology as well as from a medical point of view. Among the presently available sugar substitutes with nutritive value are mentioned Xylite, Lycasine, Mannite, Sorbite, Palatinite, the non-calorific substitutes such as the natural Aspartame as well as the synthetic sweetening agents Saccharine and Cyclamate. The possibilities and limitations of using these sugar substitutes in the prevention of caries in adults and children are presented. PMID:6532015

  14. Why Black-on-Black Homicide?

    ERIC Educational Resources Information Center

    Jeff, Morris F. X., Jr.

    1981-01-01

    The causes of homicides committed against Blacks by Blacks are examined. Major preventive measures are said to be equal opportunity, better jobs, reduction of racial discrimination, elimination of organized crime, removal of drugs from community, and better schools. (JCD)

  15. Microbiological aspects of some caloric sugar substitutes.

    PubMed

    Birkhed, D; Kalfas, S; Svenster, G; Edwardsson, S

    1985-03-01

    Several caloric sugar substitutes are available today, e.g. maltitol, Lycasin, sorbitol, xylitol, palatinit, sorbose, coupling sugar, palatinose, fructose and invert sugar. When evaluating the cariogenicity of these sugar substitutes from a bacteriological point of view, different analytical procedures should be considered. In vitro studies on the capacity of pure oral bacterial strains and dental plaque material to decompose the substitute to acid. Studies on the catabolism of the substitute. Possible adaptation of the oral microflora to metabolize the substitute in vivo as well as in vitro. Studies on any inhibitory effect of the substitute on the microbial activities in dental plaque and on the oral microflora. The capacity of oral bacteria, e.g. Streptococcus mutans, to induce caries in animal experiments should also be considered. Results from such microbiological studies make it possible to classify the caloric sugar substitutes into different groups. The first, most suitable, group seems to consist of xylitol and sorbose. These substitutes are fermented by few oral bacteria and no negative adaptation of the oral flora has been observed. A reducing effect upon dental plaque formation and on acid production from glucose has been reported. A second group consists of maltitol, palatinite, palatinose, sorbitol and Lycasin. These substitutes are fermented by certain groups of organisms within the oral genera Actinomyces, Lactobacillus and Streptococcus. Adaptation of oral bacteria to palatinose and to sorbitol, resulting in a more pronounced acid production, has been observed. No inhibitory effects have been reported. The results from experimental studies suggest that these sugar substitutes have no or little cariogenic action in rodents inoculated with S. mutans.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3858233

  16. Slip Casting of ?-Sialon/AlN/BN Powder Carbothermally Prepared by Boron-rich Slag-based Mixture

    NASA Astrophysics Data System (ADS)

    Jun-bin, Wu; Xiang-xin, Xue; Tao, Jiang; Qing, Zhang

    2011-10-01

    With boron-rich slag, silica fume, bauxite chalmette and carbon black as starting materials, ?-Sialon/AlN/BN powder was prepared by carbothermal reduction-nitridation. The powder was attrition milled to submicron size and suspended in water. The effects of yttrium oxide as a sintering aid, pH, and addition of deflocculant on the suspensions were study. Optimum slip casting properties, i.e. lowest viscosity values, the highest absolute zeta potential values, the smallest floc size and sediment volume were found at pH 10 for the powder. The suspensions were used to slip cast discs which were sintered in a nitrogen atmosphere at 1700C for 2h. The strength was about 230MPa, the toughness 3.6 MPam1/2 and the hardness about 13.8GPa.

  17. Reduction and carburization in iron powder production at the brovary powder metallurgy factory

    Microsoft Academic Search

    A. F. Zhornyak; Yu. I. Timchenko; I. M. Fedorenko

    1968-01-01

    1.Study of the reduction and carburization kinetics in iron powder furnaces exposed and led to the removal of several shortcomings in these units.2.A method has been developed for reducing the charge in porous drip pans made from rolled powders. Trials using this method showed that the porous drip pans improve heat transfer and gas permeability of the charge and so

  18. Magnetic behavior of nanocrystalline powders of Co-doped ZnO diluted magnetic semiconductors synthesized by polymerizable precursor method

    NASA Astrophysics Data System (ADS)

    Maensiri, Santi; Sreesongmuang, Jakkapon; Thomas, Chunpen; Klinkaewnarong, Jutharatana

    2006-06-01

    This paper reports the first synthesis of nanocrystalline powders of Co-doped ZnO (i.e. Zn 0.9Co 0.1O) diluted magnetic semiconductor by a polymerizable precursor method using nitrate salts of Zn and Co and a mixed solution of citric acid and ethylene glycol as a chelating agent and reaction medium, respectively. The polymeric precursors were characterized by TG-DTA to determine the thermal decomposition and crystallization temperature which was found to be at 723 K. The precursors were calcined at different temperatures of 773, 873, 973, and 1073 K for 1 h to obtain nanocrystalline powders. The morphology and crystalline size of the calcined particles were evaluated by SEM, TEM and Scherrer's equation. The average particle sizes calcined at 773, 873, 973, and 1073 K for 1 h were, respectively, 20, 60, 80, 150 nm, obtained from TEM. The XRD and Fourier transmission infrared (FT-IR) results indicated that the synthesized Zn 0.9Co 0.1O powders have the pure wurtzite structure without any significant change in the structure affected by Co substitution. Optical absorption measurements showed absorption bands indicating the presence of Co 2+ in substitution of Zn 2+. Room temperature magnetization results revealed a ferromagnetic behavior for the Zn 0.9Co 0.1O powders. Although the specific magnetization seemed to change with the particle size but there was no clear dependency since the largest magnetization was observed in the powders calcined at 873 K (60 nm). Instead, the specific magnetization appeared to show a trend of dependency on the lattice constant c of the wurtzite unit cell.

  19. Polymer powders for selective laser sintering (SLS)

    NASA Astrophysics Data System (ADS)

    Schmid, Manfred; Amado, Antonio; Wegener, Konrad

    2015-05-01

    Selective Laser Sintering (SLS) is close to be accepted as a production technique (Additive Manufacturing). However, one problem limiting employment of SLS for additive manufacturing in a wide-ranging industrial scope is the narrow variety of applicable polymers. The commonly applied SLS powder to date is polyamide 12 (PA 12). PA 12 or ccompounds of PA 12 (dry blends) are approximately 90 % of complete industrial consumption. The remaining small quantity is distributed on polyamide 11 (PA11) and some other `exotic' polymers (TPU, PEBA, P(E)EK). Industry is awaiting commodity polymers like polypropylene (PP) or polyethylene (PE) crucial to open new market segments. But several approaches launching those polymers failed. But what are the reasons for the difficulties in developing new SLS powders? The contribution is to answer this and highlights the combination of intrinsic and extrinsic polymer properties necessary to generate a polymer powder promising for SLS application. Particle shape, powder distribution, thermal, rheological and optical requirements must be considered and only a particularly controlled property combination leads to successful SLS implementation. Thermal behavior, particle shape and -distribution is discussed in detail, although the other properties can't be disregarded for providing new commercially successful SLS powder finally.

  20. Drop penetration into porous powder beds.

    PubMed

    Hapgood, Karen P; Litster, James D; Biggs, Simon R; Howes, Tony

    2002-09-15

    The kinetics of drop penetration were studied by filming single drops of several different fluids (water, PEG200, PEG600, and HPC solutions) as they penetrated into loosely packed beds of glass ballotini, lactose, zinc oxide, and titanium dioxide powders. Measured times ranged from 0.45 to 126 s and depended on the powder particle size, viscosity, surface tensions, and contact angle. The experimental drop penetration times were compared to existing theoretical predictions by M. Denesuk et al. (J. Colloid Interface Sci.158, 114, 1993) and S. Middleman ("Modeling Axisymmetric Flows: Dynamics of Films, Jets, and Drops," Academic Press, San Diego, 1995) but did not agree. Loosely packed powder beds tend to have a heterogeneous bed structure containing large macrovoids which do not participate in liquid flow but are included implicitly in the existing approach to estimating powder pore size. A new two-phase model was proposed where the total volume of the macrovoids was assumed to be the difference between the bed porosity and the tap porosity. A new parameter, the effective porosity epsilon(eff), was defined as the tap porosity multiplied by the fraction of pores that terminate at a macrovoid and are effectively blocked pores. The improved drop penetration model was much more successful at estimating the drop penetration time on all powders and the predicted times were generally within an order of magnitude of the experimental results. PMID:16290866

  1. 40 CFR 721.3565 - Ethylenediamine, substituted, sodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Ethylenediamine, substituted, sodium salt. 721.3565 Section 721.3565 ...Ethylenediamine, substituted, sodium salt. (a) Chemical substance and significant...as ethylenediamine, substituted, sodium salt (PMN P-97-328) is subject to...

  2. 40 CFR 721.8900 - Substituted halogenated pyridinol, alkali salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Substituted halogenated pyridinol, alkali salt. 721.8900 Section 721.8900 ...Substituted halogenated pyridinol, alkali salt. (a) Chemical substances and significant...substituted halogenated pyridinols, alkali salts (PMNs P-88-1271 and...

  3. 40 CFR 721.5278 - Substituted naphthalenesulfonic acid, alkali salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Substituted naphthalenesulfonic acid, alkali salt. 721.5278 Section 721.5278 ...Substituted naphthalenesulfonic acid, alkali salt. (a) Chemical substance and significant...substituted naphthalenesulfonic acid, alkali salt (PMN P-95-85) is subject to...

  4. 40 CFR 721.5278 - Substituted naphthalenesulfonic acid, alkali salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Substituted naphthalenesulfonic acid, alkali salt. 721.5278 Section 721.5278 ...Substituted naphthalenesulfonic acid, alkali salt. (a) Chemical substance and significant...substituted naphthalenesulfonic acid, alkali salt (PMN P-95-85) is subject to...

  5. 40 CFR 721.8900 - Substituted halogenated pyridinol, alkali salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Substituted halogenated pyridinol, alkali salt. 721.8900 Section 721.8900 ...Substituted halogenated pyridinol, alkali salt. (a) Chemical substances and significant...substituted halogenated pyridinols, alkali salts (PMNs P-88-1271 and...

  6. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... false Haloalkyl substituted cyclic ethers. 721.3440 Section 721.3440 ...3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant...substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  7. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... false Haloalkyl substituted cyclic ethers. 721.3440 Section 721.3440 ...3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant...substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  8. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Haloalkyl substituted cyclic ethers. 721.3440 Section 721.3440 ...3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant...substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  9. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... false Haloalkyl substituted cyclic ethers. 721.3440 Section 721.3440 ...3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant...substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  10. 40 CFR 721.10708 - Zirconium substituted heteropolycyclic (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Zirconium substituted heteropolycyclic (generic...Chemical Substances 721.10708 Zirconium substituted heteropolycyclic (generic...chemical substance identified generically as zirconium substituted heteropolycyclic...

  11. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Amine substituted metal salts. 721.640...Specific Chemical Substances 721.640 Amine substituted metal salts. (a) Chemical...chemical substances identified generically as amine substituted metal salts (PMNs...

  12. 40 CFR 721.3764 - Fluorene substituted aromatic amine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... false Fluorene substituted aromatic amine. 721.3764 Section 721.3764 ...3764 Fluorene substituted aromatic amine. (a) Chemical substance and significant...generically as a fluorene substituted aromatic amine (PMN P-91-43) is subject to...

  13. 40 CFR 721.10254 - Substituted acrylamide (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Substituted acrylamide (generic). 721.10254 Section...Substances 721.10254 Substituted acrylamide (generic). (a) Chemical substance...identified generically as substituted acrylamide (PMN P-09-390) is subject...

  14. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Acrylamide-substituted epoxy. 721.320 ...Chemical Substances 721.320 Acrylamide-substituted epoxy. (a) Chemical...chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  15. 40 CFR 721.10254 - Substituted acrylamide (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Substituted acrylamide (generic). 721.10254 Section...Substances 721.10254 Substituted acrylamide (generic). (a) Chemical substance...identified generically as substituted acrylamide (PMN P-09-390) is subject...

  16. 40 CFR 721.10254 - Substituted acrylamide (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Substituted acrylamide (generic). 721.10254 Section...Substances 721.10254 Substituted acrylamide (generic). (a) Chemical substance...identified generically as substituted acrylamide (PMN P-09-390) is subject...

  17. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Acrylamide-substituted epoxy. 721.320 ...Chemical Substances 721.320 Acrylamide-substituted epoxy. (a) Chemical...chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  18. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Acrylamide-substituted epoxy. 721.320 ...Chemical Substances 721.320 Acrylamide-substituted epoxy. (a) Chemical...chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  19. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Acrylamide-substituted epoxy. 721.320 ...Chemical Substances 721.320 Acrylamide-substituted epoxy. (a) Chemical...chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  20. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Acrylamide-substituted epoxy. 721.320 ...Chemical Substances 721.320 Acrylamide-substituted epoxy. (a) Chemical...chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  1. When You're Absent: Preparing for the Substitute.

    ERIC Educational Resources Information Center

    Fox, Brian A.

    1988-01-01

    Suggests ways classroom teachers can prepare for absences and help make substitute teaching productive. Recommends forming a list of preferred substitutes at the beginning of the school year; clarifying with students expected behavior; and preparing a permanent substitute packet. (LS)

  2. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... false Haloalkyl substituted cyclic ethers. 721.3440 Section 721.3440 ...3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant...substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  3. Substituted androstanes as aromatase inhibitors

    NASA Astrophysics Data System (ADS)

    Levina, Inna S.

    1998-11-01

    The synthesis and structure-activity relationships of inhibitors of steroid aromatase which catalyses the last stage of a multistep biotransformation of cholesterol into estrogens, viz., aromatisation of C19-steroids into C18-phenolic steroids, are discussed. Compounds of the androstane series which are structurally related to the natural substrate, viz., androst-4-ene-3,17-dione, are the subjects of consideration. The review encompasses problems of synthesis of various substituted androstanes and their aromatase-inhibiting activities and structural requirements for selective specific aromatase inhibitors based on in vitro and in vivo structure-activity studies of compounds synthesised, their biological properties and the results of clinical trials. Special attention is paid to practical applications of aromatase inhibitors in the treatment of hormone-dependent mammary and ovarian tumours as well as benign prostatic tumours. In writing this report, the author has used all the information currently available in the chemical, biochemical, endocrinological and medicinal literature as well as in patents. The bibliography includes 173 references.

  4. A hydroxycarbonate route to superconductor precursor powders

    SciTech Connect

    Voigt, J.A.; Bunker, B.C.; Doughty, D.H.; Lamppa, D.L.; Kimball, K.M.

    1987-01-01

    A precipitation process is described for the preparation of powders that can be thermally decomposed to form high critical temperature superconductors such as YBa/sub 2/Cu/sub 3/O/sub 7/. In the process, a cationic solution (a concentrated chloride or nitrate solution) is instantaneously mixed with an anionic solution (a mixture of tetramethylammonium hydroxide and carbonate) to produce a metal-hydroxycarbonate precipitate having the metal stoichiometry of the desired superconducting oxide. The calcining and sintering of the precipitates is critical in controlling the structural integrity and morphology of the superconducting cermaics made from the chem-prep powders, as well as controlling superconducting properties. Under appropriate conditions, high density (>95%) materials that exhibit good superconducting characteristics can be prepared with the chem-prep powders. 6 refs., 3 figs.

  5. Dry powder coating of pharmaceuticals: a review.

    PubMed

    Sauer, Dorothea; Cerea, Matteo; DiNunzio, James; McGinity, James

    2013-12-01

    Over the last half century, film coating technology has evolved significantly in terms of compositions and manufacturing processes, allowing for greater functionality, flexibility and efficiency. Driven by a combination of cost considerations and functionality, a range of dry powder coating technologies have been developed in both academic and industrial settings. These technologies can be generally classified into three major types based on the layer formation process: liquid assisted, thermal adhesion and electrostatic. In addition to specific manufacturing processes that must be implemented to achieve the desired product attributes, many of these techniques also require the use of novel excipients and specific formulations to provide acceptable manufacturability. This review summarizes the current dry powder coating technologies and highlights their industrial applicability with publicly disclosed case studies. Commentary on the future directions of dry powder coating is also provided. PMID:23428881

  6. Nitridation of chromium powder in ammonia atmosphere

    NASA Astrophysics Data System (ADS)

    Li, Ling; Zhen, Qiang; Li, Rong

    2015-03-01

    CrN powder was synthesized by nitriding Cr metal in ammonia gas flow, and its chemical reaction mechanism and nitridation process were studied. Through thermodynamic calculations, the Cr-N-O predominance diagrams were constructed for different temperatures. Chromium nitride formed at 7002-1200C under relatively higher nitrogen and lower oxygen partial pressures. Phases in the products were then investigated using X-ray diffraction (XRD), and the Cr2N content varied with reaction temperature and holding time. The results indicate that the Cr metal powder nitridation process can be explained by a diffusion model. Further, Cr2N formed as an intermediate product because of an incomplete reaction, which was observed by high-resolution transmission electron microscopy (HRTEM). After nitriding at 1000C for 20 h, CrN powder with an average grain size of 63 nm was obtained, and the obtained sample was analyzed by using a scanning electron microscope (SEM).

  7. Biaxially textured articles formed by powder metallurgy

    DOEpatents

    Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

    2003-10-21

    A strengthened, biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed, compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: Ni, Ag, Ag--Cu, Ag--Pd, Ni--Cu, Ni--V, Ni--Mo, Ni--Al, Ni--Cr--Al, Ni--W--Al, Ni--V--Al, Ni--Mo--Al, Ni--Cu--Al; and at least one fine metal oxide powder; the article having a grain size which is fine and homogeneous; and having a dominant cube oriented {100}<100> orientation texture; and further having a Curie temperature less than that of pure Ni.

  8. [Dry powder inhalers in cystic fibrosis].

    PubMed

    Steinkamp, G

    2014-06-01

    Inhaled medications play an important role in the daily treatment of patients with cystic fibrosis (CF). The classic route of administration was nebulisation via jet nebulisers. Respiratory delivery of fluid particles should loosen the viscid respiratory secretions, making airway clearance via cough or physiotherapy more efficient. Until recently, only jet nebulisers allowed to administer high doses of aerosolised antipseudomonal antibiotics. Powder inhalers for the treatment of cystic fibrosis have recently been made available. The newly developed powders and inhalers differ considerably from conventional dry powder inhalers used for the treatment of chronic obstructive airway disease. The present article will review two inhaled antibiotics, i.?e. tobramycin and colistin, and the hyperosmotic agent mannitol, which increases the hydration of the airways. Topics are particle engineering, efficacy and tolerability results from clinical trials, as well as functional and practical aspects related to these new drugs. PMID:24664997

  9. Black Box

    NSDL National Science Digital Library

    In this activity students observe what happens when various amounts of water are poured into a black box and propose models to explain their observations. When water is poured into the funnel, students observe that sometimes water emerges through the outlet tube and sometimes it does not. Also, the amount of water that does emerge is not constant. Students share their initial ideas with others and offer criticism to peers. They prepare and present a poster of their final, revised models. The activity involves data collection, pattern recognition, and model building. Supplemental student activities, such as a pattern recognition activity and a model reading, are used to provide explicit instruction about individual components of model building and assessment. The site includes links to instructional notes, student activities, assessment, and student work examples.

  10. Occurrence and Characterization of Cronobacter spp. in Dehydrated Rice Powder from Chinese Supermarket.

    PubMed

    Huang, Yan; Pang, Yiheng; Wang, Hong; Tang, Zhengzhu; Zhou, Yan; Zhang, Weiyu; Li, Xiugui; Tan, Dongmei; Li, Jian; Lin, Ying; Liu, Xiaoling; Huang, Weiyi; Shi, Yunliang

    2015-01-01

    Cronobacter spp. are emerging food-borne pathogens and have been identified as causative agents of meningitis and necrotizing enterocolitis in infants. Dehydrated rice is popular with a wide range of people and it is frequently used as a substitute for infant milk powder to baby older than four months. The occurrence of Cronobacter spp. was investigated in 1,012 samples of dehydrated rice powder collected from 14 manufacturers in China during 2010 to 2012. The isolates were identified using fusA allele sequencing and subtyped using pulsed-field gel electrophoresis. Seventy-six samples (7.5%) contained Cronobacter spp. The prevalence among manufacturers ranged from 0-28.8%. The 76 isolates included 4 species [Cronobacter sakazakii (52 isolates) Cronobacter malonaticus (14 isolates), Cronobacter dublinensis (7 isolates), and Cronobacter muytjensii (3 isolates)]. Twenty-three unique fusA alleles and sixty-six PFGE-patterns were detected. All isolated strains were observed to be sensitive or to show intermediate susceptibility to eight tested antimicrobial agents. The study revealed serious contamination of dehydrated rice powder by Cronobacter spp., with prevalence varying among manufacturers in China. Identified Cronobacter species, fusA alleles, and subtypes were diverse. PMID:26132635

  11. Occurrence and Characterization of Cronobacter spp. in Dehydrated Rice Powder from Chinese Supermarket

    PubMed Central

    Huang, Yan; Pang, Yiheng; Wang, Hong; Tang, Zhengzhu; Zhou, Yan; Zhang, Weiyu; Li, Xiugui; Tan, Dongmei; Li, Jian; Lin, Ying; Liu, Xiaoling; Huang, Weiyi; Shi, Yunliang

    2015-01-01

    Cronobacter spp. are emerging food-borne pathogens and have been identified as causative agents of meningitis and necrotizing enterocolitis in infants. Dehydrated rice is popular with a wide range of people and it is frequently used as a substitute for infant milk powder to baby older than four months. The occurrence of Cronobacter spp. was investigated in 1,012 samples of dehydrated rice powder collected from 14 manufacturers in China during 2010 to 2012. The isolates were identified using fusA allele sequencing and subtyped using pulsed-field gel electrophoresis. Seventy-six samples (7.5%) contained Cronobacter spp. The prevalence among manufacturers ranged from 0-28.8%. The 76 isolates included 4 species [Cronobacter sakazakii (52 isolates) Cronobacter malonaticus (14 isolates), Cronobacter dublinensis (7 isolates), and Cronobacter muytjensii (3 isolates)]. Twenty-three unique fusA alleles and sixty-six PFGE-patterns were detected. All isolated strains were observed to be sensitive or to show intermediate susceptibility to eight tested antimicrobial agents. The study revealed serious contamination of dehydrated rice powder by Cronobacter spp., with prevalence varying among manufacturers in China. Identified Cronobacter species, fusA alleles, and subtypes were diverse. PMID:26132635

  12. Atomization methods for forming magnet powders

    DOEpatents

    Sellers, Charles H. (Idaho Falls, ID); Branagan, Daniel J. (Idaho Falls, ID); Hyde, Timothy A. (Idaho Falls, ID)

    2000-01-01

    The invention encompasses methods of utilizing atomization, methods for forming magnet powders, methods for forming magnets, and methods for forming bonded magnets. The invention further encompasses methods for simulating atomization conditions. In one aspect, the invention includes an atomization method for forming a magnet powder comprising: a) forming a melt comprising R.sub.2.1 Q.sub.13.9 B.sub.1, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; b) atomizing the melt to form generally spherical alloy powder granules having an internal structure comprising at least one of a substantially amorphous phase or a substantially nanocrystalline phase; and c) heat treating the alloy powder to increase an energy product of the alloy powder; after the heat treatment, the alloy powder comprising an energy product of at least 10 MGOe. In another aspect, the invention includes a magnet comprising R, Q, B, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; the magnet comprising an internal structure comprising R.sub.2.1 Q.sub.13.9 B.sub.1.

  13. Graduating Black Males

    ERIC Educational Resources Information Center

    Bell, Edward Earl

    2010-01-01

    Background: The graduation numbers for Black males are dismal, chilling, and undeniably pathetic. The nation graduates only 47% of Black males who enter the 9th grade. The infusion of federal dollars and philanthropic support will not stop the trajectory of Black males who drop out of school. Black males face an upheaval educational battle;

  14. Black-hole thermodynamics

    Microsoft Academic Search

    J. D. Bekenstein

    1980-01-01

    The thermodynamics of black holes are discussed, considering its implications for the interconnection of gravitation, thermodynamics and quantum theory. The question of the function to be identified with the entropy of a black hole is examined in light of the principle that black holes have no hair and the irreversibility of black hole processes, and a generalized second law of

  15. 40 CFR 721.267 - N-[2-[(substituted dinitrophenyl)azo]diallylamino-4- substituted phenyl] acetamide (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...azo]diallylamino-4- substituted phenyl] acetamide (generic name). 721...azo]diallylamino-4- substituted phenyl] acetamide (generic name). (a...azo]diallylamino-4-substituted phenyl] acetamide (PMN P-95-513)...

  16. 40 CFR 721.267 - N-[2-[(substituted dinitrophenyl)azo]diallylamino-4- substituted phenyl] acetamide (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...azo]diallylamino-4- substituted phenyl] acetamide (generic name). 721...azo]diallylamino-4- substituted phenyl] acetamide (generic name). (a...azo]diallylamino-4-substituted phenyl] acetamide (PMN P-95-513)...

  17. 40 CFR 721.267 - N-[2-[(substituted dinitrophenyl)azo]diallylamino-4- substituted phenyl] acetamide (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...azo]diallylamino-4- substituted phenyl] acetamide (generic name). 721...azo]diallylamino-4- substituted phenyl] acetamide (generic name). (a...azo]diallylamino-4-substituted phenyl] acetamide (PMN P-95-513)...

  18. 40 CFR 721.267 - N-[2-[(substituted dinitrophenyl)azo]diallylamino-4- substituted phenyl] acetamide (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...azo]diallylamino-4- substituted phenyl] acetamide (generic name). 721...azo]diallylamino-4- substituted phenyl] acetamide (generic name). (a...azo]diallylamino-4-substituted phenyl] acetamide (PMN P-95-513)...

  19. 40 CFR 721.267 - N-[2-[(substituted dinitrophenyl)azo]diallylamino-4- substituted phenyl] acetamide (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...azo]diallylamino-4- substituted phenyl] acetamide (generic name). 721...azo]diallylamino-4- substituted phenyl] acetamide (generic name). (a...azo]diallylamino-4-substituted phenyl] acetamide (PMN P-95-513)...

  20. Calcium phosphate cement - gelatin powder composite testing in canine models: Clinical implications for treatment of bone defects.

    PubMed

    Yomoda, Mitsuhiro; Sobajima, Satoshi; Kasuya, Akihiro; Neo, Masashi

    2015-05-01

    Previous studies have reported the excellent biocompatibility of calcium phosphate cement. However, calcium phosphate cement needs further improvement in order for it to promote bone replacement and eventual bone substitution, as it exhibits slow biodegradability and thus remains in the body over an extended period of time. In this study, we mixed calcium phosphate cement with gelatin powder in order to create a composite containing macropores with interconnectivity, and we then implanted it into canine femurs from the diaphysis to the distal metaphysis. Eight dogs were divided into the sham group, the control (C0) group with 100 wt% calcium phosphate cement, the C10 group with 90 wt% calcium phosphate cement and 10 wt% gelatin powder, and the C15 group with 85 wt% calcium phosphate cement and 15 wt% gelatin powder. Bone replaceability in C10 and C15 at 3 and 6 months was evaluated by radiography, micro-CT, histomorphometry, and mineral apposition rate. New bone formation was seen in C10 and C15 although that was not seen in C0 at six months. The mineral apposition rate was significantly higher in C15 than in C10 in both the diaphysis and metaphysis, and the composite was found to have excellent biodegradability and bone replaceability in canine subjects. As the composite is easily and rapidly prepared, it is likely to become a new bone substitute for use in clinical settings. PMID:25550332

  1. Synthesis of ultrafine powders by microwave heating

    DOEpatents

    Meek, T.T.; Sheinberg, H.; Blake, R.D.

    1987-04-24

    A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has dissolved. The resulting material is an ultrafine powder. This method can be used to make Al/sub 2/O/sub 3/, NiO /plus/ Al/sub 2/O/sub 3/ and NiO as well as a number of other materials including GaBa/sub 2/Cu/sub 3/O/sub x/. 1 tab.

  2. Removing Undesired Fine Powder From Silicon Reactor

    NASA Technical Reports Server (NTRS)

    Flagella, Robert N.

    1992-01-01

    Fluidized-bed reactor produces highly pure polycrystalline silicon particles with diameters approximately greater than 400 micrometers. Operates by pyrolysis of silane in reaction zone, which is bed of silicon seed particles fluidized by flow of silane and carrier gas. Above reaction zone, gas mixture flows rapidly enough to entrain silicon powders, but not larger seed and product particles. Entrained particles swept out of reactor. Applicable to other processes such as production of fine metal and ceramic powders where control of sizes of product needed.

  3. Alternative carriers in dry powder inhaler formulations.

    PubMed

    Rahimpour, Yahya; Kouhsoltani, Maryam; Hamishehkar, Hamed

    2014-05-01

    The aerosolization efficiency of a powder is highly dependent on carrier characteristics, such as particle size distribution, shape and surface properties. The main objective in the inhalation field is to achieve a high and reproducible pulmonary deposition. This can be provided by successful carrier selection and careful process optimization for carrier modification. Lactose is the most common and frequently used carrier in dry powder inhaler (DPI) formulations. But lactose shows some limitations in formulation with certain drugs and peptides that prohibit its usage as a carrier in DPI formulations. Here, we criticality review the most important alternative carriers to lactose with merits, demerits and applications in DPI formulations. PMID:24269834

  4. Thermal Oxidation of Aluminum Nitride Powder

    SciTech Connect

    Gu, Zheng; Edgar, James H.; Wang, Chong M.; Coffey, Dorothy

    2006-07-31

    The kinetics of the thermal oxidation of AlN powder in flowing oxygen over temperatures from 800 to 1150 C and the morphology and crystallinity of the resultant oxide were determined. The oxidation of two types of AlN powder was investigated and compared. Complex difference in the oxidation behavior was observed, probably due to their different morphology, particle size, particle size distribution, and residual impurities. Amorphous alumina formed at relatively low oxidation temperatures (800-1000 C), with a linear oxidation rate governed by interfacial reaction. Crystalline alumina formed at higher temperatures (>1000 C), and the oxidation rate was parabolic which suggested an oxidant diffusion controlled process.

  5. Random Laser Action in Semiconductor Powder

    NASA Astrophysics Data System (ADS)

    Cao, H.; Zhao, Y. G.; Ho, S. T.; Seelig, E. W.; Wang, Q. H.; Chang, R. P. H.

    1999-03-01

    We report the first observation of random laser action with coherent feedback in semiconductor powder. Since the scattering mean free path is less than the emission wavelength, recurrent light scattering arises and provides coherent feedback for lasing. Discrete lasing modes have been observed above the threshold. The dependence of the lasing threshold intensity on the excitation volume agrees with the random laser theory. Laser emission from the powder could be observed in all directions. This observation also provides direct evidence for the existence of recurrent scattering of light.

  6. Combustion characteristics of the heat pellet prepared from the Fe powders obtained by spray pyrolysis

    Microsoft Academic Search

    J. H. Kim; H. Y. Koo; S. K. Hong; J. M. Han; H. C. Jang; Y. N. Ko; Y. J. Hong; Y. C. Kang; S. H. Kang; S. B. Cho

    Fe powders for thermal batteries were prepared by reduction of iron oxide powders obtained by spray pyrolysis. The iron oxide powders prepared by spray pyrolysis had fine size, spherical shape and high surface area. The morphologies of the Fe powders were affected by the preparation temperatures of the iron oxide powders. The Fe powders obtained from the iron oxide powders

  7. Magnetic Properties of Amorphous Fe-Si-B Powder Cores Mixed with Pure Iron Powder

    NASA Astrophysics Data System (ADS)

    Kim, Hyeon-Jun; Nam, Seul Ki; Kim, Kyu-Sung; Yoon, Sung Chun; Sohn, Keun-Yong; Kim, Mi-Rae; Sul Song, Yong; Park, Won-Wook

    2012-10-01

    Amorphous Fe-Si-B alloy was prepared by melt-spinning, and then the ribbons were pulverized and ball-milled to make the amorphous powder of 25 m in size. Subsequently those were mixed with pure iron powders with an average particle size of 3 m, and 1.5 wt % water glass diluted by distilled water at the ratio of 1:2. The powder mixtures were cold compacted at 650 MPa in toroid die, and heat treated at 430-440 C under a nitrogen atmosphere for 1 h and 30 min, respectively. The soft magnetic properties of powder core were investigated using a B-H analyzer and a flux meter at the frequency range of 100 kHz. The microstructure was observed using scanning electron microscope (SEM), and the density of the core was measured using the principle of Archimedes. Based on the experimental results, the amorphous powder mixed with pure iron powder showed the improved powder compactability, which resulted in the increased permeability and the reduced core loss.

  8. Effect of iron substitution on the structural, electric, and magnetic properties in R-type PbFeV{sub 6-x}O, a frustrated system

    Microsoft Academic Search

    O. Mentre; A. C. Dhaussy; F. Abraham; H. Steinfink

    1997-01-01

    Single-phase material of the solid solution PbFeV{sub 6-x}O was prepared by solid-state reaction over the range 1 x 1.75. Powder preparations of PbVO, however, were always accompanied by a small amount of impurity. The noncentrosymmetric space group P6mc of PbVO, which has an R-block structure, remains unchanged with iron substitution. The crystal structure, remains unchanged with iron substitution.

  9. Enzymatic hydrolysis of low substituted carboxymethyl cellulose

    E-print Network

    Chanona Dominquez, Guadalupe

    1984-01-01

    ENZYMATIC HYDROLYSIS OF LOW SUBSTITUTED CARBOXYMETHYL CELLULOSE A Thesis by GUADALUPE CHANONA DOMINGUEZ Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1984 Major Subject: Agricultural Engineering ENZYMATIC HYDROLYSIS OF LOW SUBSTITUTED CARBOXYMETHYL CELLULOSE A Thesis by GUADALUPE CHANONA DOMINGUEZ Approved as to style and content by: Cady R. Engler airman) Ed. J. Soltes (Member...

  10. Nutrient-substituted hydroxyapatites: synthesis and characterization

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.

    1999-01-01

    Incorporation of Mg, S, and plant-essential micronutrients into the structure of synthetic hydroxyapatite (HA) may be advantageous for closed-loop systems, such as will be required on Lunar and Martian outposts, because these apatites can be used as slow-release fertilizers. Our objective was to synthesize HA with Ca, P, Mg, S, Fe, Cu, Mn, Zn, Mo, B, and Cl incorporated into the structure, i.e., nutrient-substituted apatites. Hydroxyapatite, carbonate hydroxyapatite (CHA), nutrient-substituted hydroxyapatite (NHA), and nutrient-substituted carbonate hydroxyapatite (NCHA) were synthesized by precipitating from solution. Chemical and mineralogical analysis of precipitated samples indicated a considerable fraction of the added cations were incorporated into HA, without mineral impurities. Particle size of the HA was in the 1 to 40 nm range, and decreased with increased substitution of nutrient elements. The particle shape of HA was elongated in the c-direction in unsubstituted HA and NHA but more spherical in CHA and NCHA. The substitution of cations and anions in the HA structure was confirmed by the decrease of the d[002] spacing of HA with substitution of ions with an ionic radius less than that of Ca or P. The DTPA-extractable Cu ranged from 8 to 8429 mg kg-1, Zn ranged from 57 to 1279 mg kg-1, Fe from 211 to 2573 mg kg-1, and Mn from 190 to 1719 mg kg-1, depending on the substitution level of each element in HA. Nutrient-substituted HA has the potential to be used as a slow-release fertilizer to supply micronutrients, S, and Mg in addition to Ca and P.

  11. An exergetic analysis of R22 substitution

    Microsoft Academic Search

    C Aprea; A Greco

    2002-01-01

    This paper deals with the substitution of R22 in an experimental vapour compression plant with the most widely used drop-in substitute, i.e. the zeotropic mixture R407C. A comparative exergetic analysis, carried on with experimental tests, has been presented. The experimental tests are performed in a vapour compression plant working with water and air as secondary fluids in the condenser and

  12. Improved Small-Particle Powders for Plasma Spraying

    NASA Technical Reports Server (NTRS)

    Nguyen, QuynhGiao, N.; Miller, Robert A.; Leissler, George W.

    2005-01-01

    Improved small-particle powders and powder-processing conditions have been developed for use in plasma spray deposition of thermal-barrier and environmental barrier coatings. Heretofore, plasma-sprayed coatings have typically ranged in thickness from 125 to 1,800 micrometers. As explained below, the improved powders make it possible to ensure complete coverage of substrates at unprecedently small thicknesses of the order of 25 micrometers. Plasma spraying involves feeding a powder into a hot, high-velocity plasma jet. The individual powder particles melt in the plasma jet as they are propelled towards a substrate, upon which they splat to build up a coating. In some cases, multiple coating layers are required. The size range of the powder particles necessarily dictates the minimum thickness of a coating layer needed to obtain uniform or complete coverage. Heretofore, powder particle sizes have typically ranged from 40 to 70 micrometers; as a result, the minimum thickness of a coating layer for complete coverage has been about 75 micrometers. In some applications, thinner coatings or thinner coating layers are desirable. In principle, one can reduce the minimum complete-coverage thickness of a layer by using smaller powder particles. However, until now, when powder particle sizes have been reduced, the powders have exhibited a tendency to cake, clogging powder feeder mechanisms and feed lines. Hence, the main problem is one of synthesizing smaller-particle powders having desirable flow properties. The problem is solved by use of a process that begins with a spray-drying subprocess to produce spherical powder particles having diameters of less than 30 micrometers. (Spherical-particle powders have the best flow properties.) The powder is then passed several times through a commercial sifter with a mesh to separate particles having diameters less than 15 micrometers. The resulting fine, flowable powder is passed through a commercial fluidized bed powder feeder into a plasma spray jet.

  13. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet

    NASA Technical Reports Server (NTRS)

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.

    1993-01-01

    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  14. Powder-Metallurgy Process And Product

    NASA Technical Reports Server (NTRS)

    Paris, Henry G.

    1988-01-01

    Rapid-solidification processing yields alloys with improved properties. Study undertaken to extend favorable property combinations of I/M 2XXX alloys through recently developed technique of rapid-solidification processing using powder metallurgy(P/M). Rapid-solidification processing involves impingement of molten metal stream onto rapidly-spinning chill block or through gas medium using gas atomization technique.

  15. Balanced mechanical resonator for powder handling device

    NASA Technical Reports Server (NTRS)

    Sarrazin, Philippe C. (Inventor); Brunner, Will M. (Inventor)

    2012-01-01

    A system incorporating a balanced mechanical resonator and a method for vibration of a sample composed of granular material to generate motion of a powder sample inside the sample holder for obtaining improved analysis statistics, without imparting vibration to the sample holder support.

  16. Sol-Gel Synthesis Of Aluminoborosilicate Powders

    NASA Technical Reports Server (NTRS)

    Bull, Jeffrey; Leiser, Daniel; Selvaduray, Guna

    1992-01-01

    Application of sol-gel process to synthesis of aluminoborosilicate powders shows potential for control of microstructures of materials. Development of materials having enhanced processing characteristics prove advantageous in extending high-temperature endurance of fibrous refractory composite insulation made from ceramic fibers.

  17. Numerical Simulation of Aerated Powder Consolidation 1

    E-print Network

    will slowly escape by diffusing through the material. The corresponding uneven gas pressure distribution properties. Over time the excess air diffuses through the powder and eventually escapes through the top) d d p 2 FIG. 1. Geometry and coordinate systems for the vertical conical bunker. The height

  18. High-Performance Polyimide Powder Coatings

    NASA Technical Reports Server (NTRS)

    Leahy, Jonathan J.

    2014-01-01

    Researchers at NASA's Kennedy Space Center have developed advanced powder coatings for longer-lasting, improved corrosion control. The results of preliminary tests of the coatings and their resistance to salt spray corrosion are very encouraging, and commercial partners are sought for further development.

  19. Magnetic properties of dispersed magnetite powders

    Microsoft Academic Search

    L. G. Parry

    1965-01-01

    Measurements have been made of coercive force, susceptibility, isothermal remanence, thermoremanence and thermal and alternating field demagnetization of annealed magnetite powders in nine size ranges from 15 ? to 120 ?. The samples were dispersed in plaster to occupy a few per cent by volume of the specimens and thus to simulate the magnetic properties of rocks. The results are

  20. MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON

    EPA Science Inventory

    The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...

  1. Plated Metal Powders for Electrode Pastes

    NASA Technical Reports Server (NTRS)

    Bickler, D. B.

    1984-01-01

    Metal grains to be sintered precoated with frit metal. Coated metal powders used to make ink-like electrode pastes for printing and sintering electrode-fabrication process. Grains of base metal coated with lowmelting-point--, lead or tin-- by electroless deposition.

  2. Strengthening of face packing surfaces with powders

    Microsoft Academic Search

    N. N. Dorozhkin; V. N. Gimelfarb; L. P. Kashitsyn

    1983-01-01

    The Institute of Problems of Reliability and Life of Machines of the Academy of Sciences of the Belorussian SSR has developed a process of induction coalescing under the action of an activating pressure at the sintering temperature of powder under conditions of accelerated heating and realization of the so-called effect of limited space. Proposed is a method for strengthening the

  3. Screening mail for powders using terahertz technology

    NASA Astrophysics Data System (ADS)

    Kemp, Mike

    2011-11-01

    Following the 2001 Anthrax letter attacks in the USA, there has been a continuing interest in techniques that can detect or identify so-called 'white powder' concealed in envelopes. Electromagnetic waves (wavelengths 100-500 ?m) in the terahertz frequency range penetrate paper and have short enough wavelengths to provide good resolution images; some materials also have spectroscopic signatures in the terahertz region. We report on an experimental study into the use of terahertz imaging and spectroscopy for mail screening. Spectroscopic signatures of target powders were measured and, using a specially designed test rig, a number of imaging methods based on reflection, transmission and scattering were investigated. It was found that, contrary to some previous reports, bacterial spores do not appear to have any strong spectroscopic signatures which would enable them to be identified. Imaging techniques based on reflection imaging and scattering are ineffective in this application, due to the similarities in optical properties between powders of interest and paper. However, transmission imaging using time-of-flight of terahertz pulses was found to be a very simple and sensitive method of detecting small quantities (25 mg) of powder, even in quite thick envelopes. An initial feasibility study indicates that this method could be used as the basis of a practical mail screening system.

  4. Macromolecular powder diffraction : structure solution via molecular.

    SciTech Connect

    Doebbler, J.; Von Dreele, R.; X-Ray Science Division

    2009-01-01

    Macromolecular powder diffraction is a burgeoning technique for protein structure solution - ideally suited for cases where no suitable single crystals are available. Over the past seven years, pioneering work by Von Dreele et al. [1,2] and Margiolaki et al. [3,4] has demonstrated the viability of this approach for several protein structures. Among these initial powder studies, molecular replacement solutions of insulin and turkey lysozyme into alternate space groups were accomplished. Pressing the technique further, Margiolaki et al. [5] executed the first molecular replacement of an unknown protein structure: the SH3 domain of ponsin, using data from a multianalyzer diffractometer. To demonstrate that cross-species molecular replacement using image plate data is also possible, we present the solution of hen egg white lysozyme using the 60% identical human lysozyme (PDB code: 1LZ1) as the search model. Due to the high incidence of overlaps in powder patterns, especially in more complex structures, we have used extracted intensities from five data sets taken at different salt concentrations in a multi-pattern Pawley refinement. The use of image plates severely increases the overlap problem due to lower detector resolution, but radiation damage effects are minimized with shorter exposure times and the fact that the entire pattern is obtained in a single exposure. This image plate solution establishes the robustness of powder molecular replacement resulting from different data collection techniques.

  5. Thin transparent films formed from powdered glass

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Glass film less than five mils thick is formed from powdered glass dispersed in an organic liquid, deposited on a substrate, and fused into place. The thin films can be cut and shaped for contact lenses, optical filters and insulating layers.

  6. Electrohydraulic-impulse pressing of refractory powders

    Microsoft Academic Search

    K. N. Bogoyavlenskii; P. A. Kuznetsov; K. K. Mertens; V. V. Podgornyi; L. V. Kravets; V. M. Yam

    1982-01-01

    Conclusions It was experimentally established that it is possible to use electrohydraulic-impulse pressing to improve the basic physical properties of articles prepared from low-plasticity refractory powders. The advantages of making articles by combined pressing, including static pressing in a rigid mold and final electrohydraulic-impulse pressing were demonstrated.

  7. Cold spray deposition of thermoplastic powder

    Microsoft Academic Search

    Y. Xu; I. M. Hutchings

    2006-01-01

    The cold spray deposition of polyolefin powder has been investigated, at substantially lower velocities (up to ?135m s?1) than those used in the cold gas dynamic spray (CGDS) process for metals. The particles were accelerated at room temperature in air through a cylindrical nozzle, and were deposited on to polyethylene and aluminium substrates. Fully-dense deposits were formed at temperatures substantially

  8. Problems of powder flow in tabletting processes

    Microsoft Academic Search

    J. A. Hersey

    1965-01-01

    Summary The flow of non-compacted granules in the tablet machine hopper is discussed with relevance to the unit dose of drug, which is required to be dispensed. The various factors used to describe powder flow such as angle of repose, interparticulate cohesion and friction, flow through apertures, bulk density and die fillability are considered. The effects of humidity and of

  9. Magnetic properties and microstructure of mechanically milled Sm2(Co,M)17-based powders with M=Zr, Hf, Nb, V, Ti, Cr, Cu and Fe

    NASA Astrophysics Data System (ADS)

    Chen, Zhongmin; Meng-Burany, X.; Okumura, Hideyuki; Hadjipanayis, G. C.

    2000-04-01

    The structure, microstructure, and magnetic properties of nanostructured Sm2Co17-based powders synthesized by mechanically milling and subsequent annealing have been systematically studied. It has been found that a nanoscale 2:17 phase with an average grain size of about 30 nm is developed within the powders, which have an average particle size of about 5 ?m. Optimum magnetic properties of Ms=110.5 emu/g, Mr=66.2 emu/g, Mr/Ms=0.60, Hc=9.6 kOe, and (BH)m=10.8 MGOe have been obtained in stoichiometric Sm2Co17 powders milled for 6 h and annealed at 800 C for 30 min. The observed magnetic hardening is believed to arise from the high anisotropy of the Sm2Co17 phase and its nanoscale grain size. A small amount of Zr substitution for Co significantly increases the coercivity by increasing the anisotropy field of the Sm2Co17 phase. Cu substitution in Zr-contained samples further increases the coercivity by introducing a nanoscale 1:5 phase which forms a uniform mixture with the 2:17 nanograins. The highest coercivity of 20.6 kOe has been obtained in the Sm12(Co0.92Cu0.06Zr0.02)88 powders. Fe substitution enters the Co lattice sites of the 2:17 structure, leading to an increase of the magnetization but a decrease of the coercivity. An optimum maximum energy product of 14.0 MGOe is obtained in the Sm12(Co0.7Fe0.3)88 powders.

  10. Surface dose measurement using TLD powder extrapolation

    SciTech Connect

    Rapley, P. [Regional Cancer Care, Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario (Canada)]. E-mail: rapleyp@tbh.net

    2006-10-01

    Surface/near-surface dose measurements in therapeutic x-ray beams are important in determining the dose to the dermal and epidermal skin layers during radiation treatment. Accurate determination of the surface dose is a difficult but important task for proper treatment of patients. A new method of measuring surface dose in phantom through extrapolation of readings from various thicknesses of thermoluminescent dosimeter (TLD) powder has been developed and investigated. A device was designed, built, and tested that provides TLD powder thickness variation to a minimum thickness of 0.125 mm. Variations of the technique have been evaluated to optimize precision with consideration of procedural ease. Results of this study indicate that dose measurements (relative to D{sub max}) in regions of steep dose gradient in the beam axis direction are possible with a precision (2 standard deviations [SDs]) as good as {+-} 1.2% using the technique. The dosimeter was developed and evaluated using variation to the experimental method. A clinically practical procedure was determined, resulting in measured surface dose of 20.4 {+-} 2% of the D{sub max} dose for a 10 x 10 cm{sup 2}, 80-cm source-to-surface distance (SSD), Theratron 780 Cobalt-60 ({sup 60}C) beam. Results obtained with TLD powder extrapolation compare favorably to other methods presented in the literature. The TLD powder extrapolation tool has been used clinically at the Northwestern Ontario Regional Cancer Centre (NWORCC) to measure surface dose effects under a number of conditions. Results from these measurements are reported. The method appears to be a simple and economical tool for surface dose measurement, particularly for facilities with TLD powder measurement capabilities.

  11. Metal Powder ProcessingMetal Powder Processing ME 4210: Manufacturing Processes and Engineering

    E-print Network

    Colton, Jonathan S.

    shields Valve inserts, bushings, gears Electrical/electronic Heat treating Joining Lubrication Ag, Au, Mo is called greenp p g compact. (b) Typical tool and die set for compacting a spur gear. Source: Metal Powder

  12. Brane world black rings

    NASA Astrophysics Data System (ADS)

    Sahay, Anurag; Sengupta, Gautam

    2007-06-01

    Five dimensional neutral rotating black rings are described from a Randall-Sundrum brane world perspective in the bulk black string framework. To this end we consider a rotating black string extension of a five dimensional black ring into the bulk of a six dimensional Randall-Sundrum brane world with a single four brane. The bulk solution intercepts the four brane in a five dimensional black ring with the usual curvature singularity on the brane. The bulk geodesics restricted to the plane of rotation of the black ring are constructed and their projections on the four brane match with the usual black ring geodesics restricted to the same plane. The asymptotic nature of the bulk geodesics are elucidated with reference to a bulk singularity at the AdS horizon. We further discuss the description of a brane world black ring as a limit of a boosted bulk black 2 brane with periodic identification.

  13. Quantum Black Holes. Black Hole Temperature without a Black Hole

    E-print Network

    Victor Berezin

    2008-12-24

    The model is constructed, some features of which comes from quantum thin dust shells and is, in fact, an extension of the "no hair" property of classical black hole on a quantum level. It appears that the proposed classical analog of quantum black hole is heated, the temperature being exactly the Hawking's temperature.

  14. The Black Black Woman and the Black Middle Class.

    ERIC Educational Resources Information Center

    Jeffers, Trellie

    1981-01-01

    Reprint of a 1973 article that describes the discrimination that particularly dark-skinned Black women suffer, especially at the hands of a color-conscious Black middle class. Calls for dark women to look to the African appearance and working-class roots as sources of pride and strength. (GC)

  15. Consolidation of aluminum 6061 powder by equal channel angular extrusion

    E-print Network

    Pearson, John Montgomery

    1997-01-01

    Equal channel angular extrusion is a promising approach to obtaining full density in powder metallurgy applications. This method can impose large effective deformations through uniform shear strain. Aluminum alloy 6061 powder is used as a test...

  16. Rheological and Thermal Debinding Behaviors in Titanium Powder Injection Molding

    NASA Astrophysics Data System (ADS)

    Park, Seong-Jin; Wu, Yunxin; Heaney, Donald F.; Zou, Xin; Gai, Guosheng; German, Randall M.

    2009-01-01

    Powder injection molding (PIM) is suitable for the fabrication of complex shape titanium and its alloys and has a great potential in many applications. This article deals with the injection molding of hydride-dehydride (HDH) titanium powder, spheroidized HDH titanium powder, and gas-atomized (GA) titanium powder. Rheological and thermal debinding behaviors are compared between feedstocks made from the three powders. Torque and capillary rheometers are used to investigate rheological behavior as it relates to the power-law model of viscosity and moldability index. Thermogravimetric analysis (TGA) was employed to analyze debinding behavior given a master decomposition curve consisting of two sigmoids. Spheroidized HDH Ti powder behaves in a manner similar to GA Ti powder. The analysis of the results in this study indicates the possibility of using a combination of HDH and GA titanium powders for PIM.

  17. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  18. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  19. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  20. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  1. 21 CFR 520.2613 - Trimethoprim and sulfadiazine powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Trimethoprim and sulfadiazine powder. 520.2613 Section 520...DRUGS 520.2613 Trimethoprim and sulfadiazine powder. (a) Specifications...of trimethoprim and 333 milligrams of sulfadiazine. (b) Sponsor. See No....

  2. In vitro bioactivity of a biocomposite fabricated from HA and Ti powders by powder metallurgy method

    Microsoft Academic Search

    C. Q. Ning; Y. Zhou

    2002-01-01

    Traditionally, hydroxyapatite was used as a coating material on titanium substrate by various techniques. In the present work, a biocomposite was successfully fabricated from hydroxyapatite and titanium powders by powder metallurgy method. Bioactivity of the composite in a simulated body fluid (SBF) was investigated. Main crystal phases of the as-fabricated composite are found to be Ti2O, CaTiO3, CaO, ?-Ti and

  3. Study on the structural and electromagnetic properties of Tm-substituted Mg-Mn ferrites by a solution combustion method

    NASA Astrophysics Data System (ADS)

    Lwin, Nilar; Othman, Radzali; Sreekantan, Srimala; Ahmad Fauzi, M. N.

    2015-07-01

    The effect of thulium ion substitution for iron on the structural and electromagnetic properties of Mg-Mn ferrites is reported. The Mg0.9Mn0.1TmxFe1.8-xO4 ferrite compositions with x=0.0, 0.025, 0.05, and 0.075 were synthesized by a nitrate-citrate solution combustion method. Tm substitution had taken place and this was found to produce a secondary phase TmFeO3. The crystallite size of the powder calcined at 500 C was in the range of 9-13 nm. Subsequently, the calcined ferrite powders were compacted and sintered at 1250 C. It was found that the physical and magnetic properties had changed with Tm contents. Bulk density was found to decrease from 4.26 to 3.82 g/cm3 with increasing Tm contents. It was also found that the saturation magnetization (Ms=38.41-23.62 emu/g) had decreased with an increase of Tm. In this study, the highest resistivity (39.84106 ? cm) was observed for Mg0.9Mn0.1Fe1.725Tm0.075O4. The correlation between structural and electromagnetic properties of the Tm-substituted samples is interpreted based on phase composition as well as microstructure.

  4. Kinetics of bacterial death by heated dolomite powder slurry

    Microsoft Academic Search

    Jun Sawai; Kyoko Himizu; Osamu Yamamoto

    2005-01-01

    The kinetics of the bactericidal action of dolomite powders heated at 6001000C against Escherichia coli and Staphylococcus aureus were investigated. Dolomite powder heated to at least 700C exhibited bactericidal action, and the process of bacterial death in the heated dolomite powder slurries followed first-order reaction kinetics. The value of the death rate constant (k) increased with dolomite powder concentration, and

  5. High temperature shock consolidation of hard ceramic powders

    NASA Astrophysics Data System (ADS)

    Hokamoto, K.; Tanaka, S.; Fujita, M.; Itoh, S.; Meyers, M. A.; Chen, H.-C.

    1997-02-01

    High-temperature shoch consolidation of hard ceramic powders was used as a means to improve bonding between powders and to decrease the number of cracks generated in the consolidated sample. A converging underwater shock-wave assembly was used for the compaction, and TiB 2, c-BN and their mixed powders were consolidated at various conditions up to 850C. The positive effects by heating the powders were confirmed by the experiments conducted.

  6. Aero-sol-gel Reactor for Nano-powder Synthesis

    Microsoft Academic Search

    G. Beaucage; J. Hyeon-Lee; D. J. Kohls; S. E. Pratsinis

    1999-01-01

    This paper discusses a new approach to the synthesis of nano-structured oxides where sol-gel reactions are carried out in aerosol droplets. This aero-sol-gel (ASG) reactor allows for manipulation of the structure, chemical composition and surface area of silica powders through variation of process parameters. ASG powders differ in nanostructure from other continuous process powders such as pyrolytic and solution-route powders.

  7. Calculation of laser absorption by metal powders in additive manufacturing.

    PubMed

    Boley, C D; Khairallah, S A; Rubenchik, A M

    2015-03-20

    We have calculated the absorption of laser light by a powder of metal spheres, typical of the powder employed in laser powder-bed fusion additive manufacturing. Using ray-trace simulations, we show that the absorption is significantly larger than its value for normal incidence on a flat surface, due to multiple scattering. We investigate the dependence of absorption on powder content (material, size distribution, and geometry) and on beam size. PMID:25968537

  8. Study on starch- graft-acrylamide\\/mineral powder superabsorbent composite

    Microsoft Academic Search

    Jihuai Wu; Yueling Wei; Jianming Lin; Songbai Lin

    2003-01-01

    A novel starch-graft-acrylamide\\/mineral powder superabsorbent composite with water absorbency about 4000 times is synthesized by graft-copolymerization reaction among acrylamide, potato starch and mineral ultrafinepowder, followed by hydrolysis with sodium hydroxide. It is found that the composite doped with kaolinite powder possess higher water absorbency than those doped with bentonite or sercite powder, since the kaolinite powder can moderately disperse in

  9. Sintering characteristics of highly active UO2 powder

    SciTech Connect

    Saiki, Wataru; Onoue, Takeshi; Hasegawa, Shinichi [Mitsubishi Metal Company, Ibaraki (Japan)] [and others

    1995-12-31

    A highly active UO{sub 2} powder of 5 to 15m{sup 2}/g specific surface area can be obtained by a conversion process we have developed. This powder can be sintered to high density at a lower temperature than conventional powder; thus, the sintering temperature can be lowered in the manufacturing plant. In this study, sintering characteristics of the active powder, such as correlation of density with temperature, grain growth with sintering time, etc., have been evaluated.

  10. Study of Velocity and Materials on Tribocharging of Polymer Powders for Powder Coating Applications

    NASA Technical Reports Server (NTRS)

    Biris, Alex S.; Trigwell, Steve; Sims, Robert A.; Mazumder, Malay K.

    2005-01-01

    Electrostatic powder deposition is widely used in a plethora of industrial-applications ranging from the pharmaceutical and food.industries, to farm equipment and automotive applications. The disadvantages of this technique are possible back corona (pin-like formations) onset and the Faraday penetration limitation (when the powder does not penetrate in some recessed areas). A possible solution to overcome these problems is to use tribochargers to electrostatically charge the powder. Tribocharging, or contact charging while two materials are in contact, is related to the work function difference between the contacting materials and generates bipolarly charged particles. The generation of an ion-free powder cloud by tribocharging with high bipolar charge and an overall charge density of almost zero, provides a better coverage of the recessed areas. In this study, acrylic and epoxy powders were fluidized and charged by passing through stainless steel, copper, aluminum, and polycarbonate static mixers, respectively. The particle velocity was varied to determine its effect on the net charge-to-mass ratio (QIM) acquired by the powders. In general, the Q/M increases rapidly when the velocity was increased from 1.5 to 2.5 m/s, remaining almost constant for higher velocities. Charge separation experiments showed bipolar charging for all chargers.

  11. Stabilizing formulations for inhalable powders of live-attenuated measles virus vaccine.

    PubMed

    Burger, Jessica L; Cape, Stephen P; Braun, Chad S; McAdams, David H; Best, Jessica A; Bhagwat, Pradnya; Pathak, Pankaj; Rebits, Lia G; Sievers, Robert E

    2008-03-01

    Carbon dioxide Assisted Nebulization with a Bubble Dryer((R)) (CAN-BD) processing allows particles to be made in the 3-5 mum size range, which is desirable for lung delivery, without destroying biological activity. In response to the Grand Challenge in Global Health Initiative #3, we have been developing an inhalable needle-free live-attenuated measles virus vaccine for use in developing countries. Measles was chosen because it is the number one vaccine preventable killer of children worldwide. Powders were processed by CAN-BD, where a solution containing excipients and live-attenuated measles virus in water was mixed intimately with supercritical or near superctitical carbon dioxide to form an emulsion. The emulsion was expanded to atmospheric pressure through a flow restrictor. The resulting plume was dried by heated nitrogen and the powders collected on a filter at the bottom of the drying chamber. Powders were analyzed using varying techniques including X-ray diffraction, scanning electron microscopy, Andersen cascade impaction, differential scanning calorimetery, Karl Fischer titration, and viral plaque assay. CAN-BD has been used to produce powders of live-attenuated measles virus vaccine with characteristics desirable for lung delivery. The powders retain viral activity through forming and drying the microparticles by CAN-BD, and have passed the WHO stability test for 1 week at 37 degrees C. The powders have an amorphous character and a glass transition temperature of around 60 degrees C. Lyophilization, the present standard commercial method of processing measles vaccine makes solids with a water content of less than 1%. By substituting myo-inositol for sorbitol and using the CAN-BD drying technique the water content can be lowered to 0.5%. The most successful formulations to date have been based conceptually on the current lyophilized formulation, but with modifications to the type and amounts of sugar. Of current interest are formulations containing myo-inositol, as they retain high viral activity and have low initial water content. PMID:18518829

  12. High-purity, fine-particle boron nitride powder synthesis at -75 to 750C. Report of investigations/1986

    SciTech Connect

    Kalyoncu, R.S.

    1986-01-01

    Nonoxide ceramics with improved high-temperature properties could substitute for high-temperature alloys and reduce the Nation's dependence on imports of Cr, Co, Ni, and Mn. To meet the objective, the Bureau of Mines conducted research to synthesize ultrafine reactive boron nitride (BN) powders. BN powders were prepared at temperatures ranging from -75 degrees to 750 degrees C. Low-temperature reactions (-75 to 200/sup 0/C) between boron halides and N compounds led to formation of elemento-organic compounds that were thermally decomposed to ultrafine (approximately 100- to 150-A particle size) reactive BN powders. BN powders were also prepared through the reaction of a low-melting inorganic B compound (boric acid, borax) with an organic N compound (carbimide and thiocarbimide) in N/sub 2/ and/or ammonia (NH/sub 3/) atmospheres at temperatures between 500 and 750/sup 0/C. The report is based upon work done under an agreement between the University of Alabama and the Bureau of Mines.

  13. Optical properties of undoped and Mg doped CuCrO2 powders synthesized by sol-gel route

    NASA Astrophysics Data System (ADS)

    Srinivasan, Radhakrishnan; Bolloju, Satish

    2014-01-01

    In this work, CuCrO2 was synthesized by sol-gel method using citric acid as a gelling agent. The different parameters like ratio of citric acid to metal ions, calcination temperature, and duration were studied. A green colored powder with particle size around 300 nm was formed at the calcination temperature of 800 C for four hours duration. The increase in temperature has a profound impact on crystallite size and in turn effected the optical properties. Band gap of the obtained CuCrO2 has varied from 2.3 to 1.7 eV by increasing the temperature from 800 C to 900 C. Doping studies were performed by introducing Mg2+ ion to substitute Cr3+ in CuCrO2. X-ray powder diffraction and SEM studies on 2% Mg doped samples indicated a clear formation of side phases. According to the X-ray powder patterns, the reflections from side phases were increasing with the increase in doping concentrations of Mg from 2 to 5%. The side phases were found to be MgCr2O4 spinel and CuO. The band gap has decreased for doped samples in comparison to undoped one. In this paper, sol-gel synthesis and characterization by Xray powder diffraction, SEM studies and UV-Vis-Diffuse Reflectance spectra are presented.

  14. Engineering Our work is focused on the study of Powder

    E-print Network

    powder transport and burning, electrostatic precipitation and heat transfer. At CCNY, he did researchChemical Engineering Abstract Our work is focused on the study of Powder Mechanics and the ultimate goal is to develop a quantitative description of flows for a wide variety of powders using a continuous

  15. Heating of metallic powders by microwaves: Experiment and theory

    Microsoft Academic Search

    V. D. Buchelnikov; D. V. Louzguine-Luzgin; G. Xie; S. Li; N. Yoshikawa; M. Sato; A. P. Anzulevich; I. V. Bychkov; A. Inoue

    2008-01-01

    It is known that bulk metallic samples reflect microwaves while powdered samples can absorb such radiation and be heated efficiently. In the present work we studied heating mechanisms of metallic powders in a multimode 2.45 GHz microwave applicator. The present paper shows direct evidence of penetration of a layer of metallic powder by microwave radiation and provides theoretical explanation of

  16. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2009-04-01 true Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  17. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  18. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  19. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  20. 21 CFR 176.350 - Tamarind seed kernel powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Tamarind seed kernel powder. 176.350 Section 176.350...of Paper and Paperboard 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a...

  1. Free radical interactions between raw materials in dry soup powder.

    PubMed

    Raitio, Riikka; Orlien, Vibeke; Skibsted, Leif H

    2011-12-01

    Interactions at the free radical level were observed between dry ingredients in cauliflower soup powder, prepared by dry mixing of ingredients and rapeseed oil, which may be of importance for quality deterioration of such dry food products. The free radical concentrations of cauliflower soup powder, obtained by electron spin resonance (ESR) spectroscopy, rapidly become smaller during storage (40C and relative humidity of 75%) than the calculated concentrations of free radicals based on the free radical concentrations of the powder ingredients used to make the soup powder and stored separately under similar conditions. Similarly, free radical concentrations decreased faster when any combination of two powder ingredients (of the three major ingredients of the soup powder) were mixed together and stored at 50C for 1week than when each powder component was stored separately. Furthermore, yeast extract powder was found to play a key role when free radical interactions between powder ingredients occurred. The incubation of rapeseed oil with powder ingredients at 45C for 24h, indicated the ability of cauliflower powder to increase the concentration of hydroperoxides in rapeseed oil, while yeast extract powder was found to prevent this hydroperoxide formation. PMID:25212323

  2. Spouting of fine powder from vertically vibrated bed

    Microsoft Academic Search

    S. Harada; H. Li; K. Funatsu; Y. Tomita

    2002-01-01

    Experimental and numerical studies of spouting of powder from vertically vibrated bed are performed. The powder flows out vigorously through a side orifice of the vertically vibrated vessel in which the powder is contained, provided that the vibration acceleration is greater than the gravitational one. The mechanism of the efflux and the relationship between the efflux rate and the vibration

  3. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  4. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  5. 21 CFR 169.182 - Vanilla-vanillin powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182 Food...Dressings and Flavorings 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the definition and...

  6. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation Other Regulations...Class 1 and Class 7 173.171 Smokeless powder for small arms. Powders that have been classed in Division 1.3 or...

  7. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  8. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  9. 49 CFR 173.171 - Smokeless powder for small arms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Smokeless powder for small arms. 173.171 Section 173.171 Transportation...Class 7 173.171 Smokeless powder for small arms. Smokeless powder for small arms which has been classed in Division 1.3...

  10. Barium strontium titanate powders prepared by spray pyrolysis

    Microsoft Academic Search

    G. Brankovi?; Z. Brankovi?; M. S. Ges; C. O. Paiva-Santos; M. Cilense; J. A. Varela; E. Longo

    2005-01-01

    Ultasonic spray pyrolysis (SP) has been investigated for the production of the barium strontium titanate (BST) powders from the polymeric precursors. The processing parameters, such as flux of aerosol and temperature profile inside the furnace, were optimized to obtain single phase BST. The powders were characterized by the methods of X-ray diffraction analysis, SEM, EDS and TEM. The obtained powders

  11. Manufacture and application of high milk protein powder1

    E-print Network

    Boyer, Edmond

    Review Manufacture and application of high milk protein powder1 Vikram V. MISTRY MN-SD Dairy Foods was developed for the production of a high milk protein powder that was rich in both milk proteins, casein with the most lactose, such as skim milk powder, had the most wrinkles. The virtual absence of lactose

  12. Electrical resistivity of carbon black-filled high-density polyethylene (HDPE) composite containing radiation crosslinked HDPE particles

    Microsoft Academic Search

    Myong-Goo Lee; Young Chang Nho

    2001-01-01

    The room-temperature volume resistivity of high-density polyethylene (HDPE)carbon black (CB) blends containing previously radiation crosslinked HDPE powder was studied. The results showed that the room-temperature volume resistivity decreases with increasing concentration of crosslinked HDPE powder. It is considered that the crosslinked HDPE particles act as a filler that increases the CB volume fraction in the HDPE matrix. The results of

  13. A Solid-State NMR Study of Selenium Substitution into Nanocrystalline Hydroxyapatite

    PubMed Central

    Kolmas, Joanna; Kuras, Marzena; Oledzka, Ewa; Sobczak, Marcin

    2015-01-01

    The substitution of selenium oxyanions in the hydroxyapatite structure was examined using multinuclear solid-state resonance spectroscopy (ssNMR). The study was supported by powder X-ray diffractometry (PXRD) and wavelength dispersion X-ray fluorescence (WD-XRF). Samples of pure hydroxyapatite (HA300) and selenate (HA300-1.2SeO4) or selenite (HA300-1.2SeO3) substituted hydroxyapatites were synthesized using the standard wet method and heated at 300 C to remove loosely bonded water. PXRD data showed that all samples are single-phase, nanocrystalline hydroxyapatite. The incorporation of selenite and selenate ions affected the lattice constants. In selenium-containing samples the concentration of Se was very similar and amounted to 9.55% and 9.64%, for HA300-1.2SeO4 and HA300-1.2SeO3, respectively. PXRD and ssNMR data showed that the selenite doping significantly decreases the crystallite size and crystallinity degree. 31P and 1H NMR experiments demonstrated the developed surface hydrated layer in all samples, especially in HA300-1.2SeO3. 1H NMR studies showed the dehydroxylation of HA during the selenium oxyanions substitution and the existence of hydrogen bonding in structural hydroxyl group channels. 1H?77Se cross polarization NMR experiments indicated that selenites and selenates are located in the crystal lattice and on the crystal surface. PMID:25997001

  14. Influence of strontium for calcium substitution in bioactive glasses on degradation, ion release and apatite formation

    PubMed Central

    Fredholm, Yann C.; Karpukhina, Natalia; Brauer, Delia S.; Jones, Julian R.; Law, Robert V.; Hill, Robert G.

    2012-01-01

    Bioactive glasses are able to bond to bone through the formation of hydroxy-carbonate apatite in body fluids while strontium (Sr)-releasing bioactive glasses are of interest for patients suffering from osteoporosis, as Sr was shown to increase bone formation both in vitro and in vivo. A melt-derived glass series (SiO2P2O5CaONa2O) with 0100% of calcium (Ca) replaced by Sr on a molar base was prepared. pH change, ion release and apatite formation during immersion of glass powder in simulated body fluid and Tris buffer at 37C over up to 8 h were investigated and showed that substituting Sr for Ca increased glass dissolution and ion release, an effect owing to an expansion of the glass network caused by the larger ionic radius of Sr ions compared with Ca. Sr release increased linearly with Sr substitution, and apatite formation was enhanced significantly in the fully Sr-substituted glass, which allowed for enhanced osteoblast attachment as well as proliferation and control of osteoblast and osteoclast activity as shown previously. Studying the compositionstructureproperty relationship in bioactive glasses enables us to successfully design next-generation biomaterials that combine the bone regenerative properties of bioactive glasses with the release of therapeutically active Sr ions. PMID:21993007

  15. The crystal and magnetic structure of Ti-substituted LaCrO{sub 3}

    SciTech Connect

    Martinelli, A., E-mail: amartin@chimica.unige.it [CNR-SPIN, C.so Perrone 24, 16152 Genova (Italy); Ferretti, M. [CNR-SPIN, C.so Perrone 24, 16152 Genova (Italy) [CNR-SPIN, C.so Perrone 24, 16152 Genova (Italy); Dipartimento di Chimica e Chimica Industriale, Universita di Genova, Via Dodecaneso 31, 16146 Genova (Italy); Cimberle, M.R. [CNR-IMEM, Via Dodecaneso 33, 16146, Genova (Italy)] [CNR-IMEM, Via Dodecaneso 33, 16146, Genova (Italy); Ritter, C. [Institute Laue - Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9 (France)] [Institute Laue - Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9 (France)

    2011-02-15

    Graphical abstract: Rietveld refinement plot of La(Cr{sub 0.90}Ti{sub 0.10})O{sub 3}; the inset shows the antiferromagnetic G{sub x}-type structure occurring at the Cr sub-lattice. Research highlights: {yields} Magnetic structure of Ti-substituted LaCrO{sub 3}. {yields} Spins on the Cr-site order according to an antiferromagnetic G{sub x}-type ordering. {yields} Limited solid state solubility of Ti{sup 4+} in LaCrO{sub 3} and mixed valence at Cr site. -- Abstract: The crystal and magnetic structures of LaCrO{sub 3} and La(Cr{sub 0.90}Ti{sub 0.10})O{sub 3} have been investigated between 5 and 350 K by means of neutron powder diffraction and DC magnetic measurements. Both compounds are characterized by an antiferromagnetic G{sub x}-type ordering at low temperature. Structural features suggest the occurrence of Ti in the tetra-valent state. Despite the mixed valence induced by Ti-substitution leading to the occurrence of the Jahn-Teller species Cr{sup 2+}, no evidence for long range ferromagnetism can be detected. On account of a miscibility gap, a higher degree of Ti-substitution at the Cr site cannot be achieved; as a consequence the solid state solubility of Ti in LaCrO{sub 3} at 1573 K has been ascertained.

  16. Electronic and structural influence of Ni by Pd substitution on the hydrogenation properties of TiNi

    SciTech Connect

    Emami, Hoda; Souques, Raphaeel [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France)] [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France); Crivello, Jean-Claude, E-mail: crivello@icmpe.cnrs.fr [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France)] [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France); Cuevas, Fermin [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France)] [Chimie Metallurgique des Terres Rares, Institut de Chimie et des Materiaux Paris-Est, CNRS, Universite Paris-Est, UMR 7182, 2-8 rue Henri Dunant, F-94320 Thiais (France)

    2013-02-15

    In Ti (Ni,Pd) compounds, the hydrogen capacity and the stability of their hydrides decreases when Ni is partially substituted by larger in size Pd atoms. To understand this peculiar behaviour, the crystal structure of TiNi{sub 1-x}Pd{sub x}D{sub y} (x=0.1, 0.3 and 0.5) deuterides and the stability of TiNi{sub 1-x}Pd{sub x} (0{<=}x{<=}0.5) intermetallics and their hydrides have been investigated by both neutron diffraction experiments and Density Functional Theory (DFT) calculations. Neutron diffraction shows that at x=0.1 and 0.3, deuterium absorption induces tetragonal distortion in intermetallics sublattice whereas at x=0.5 the cubic symmetry is preserved. The structural properties and the heat of formation of TiNi{sub 1-x}Pd{sub x} (0{<=}x{<=}0.5) intermetallics and their hydrides have been determined by DFT. These results show that Pd substitution increases the stability of the intermetallics and decreases the stability of the hydrides, which confirms the rule of reverse stability. - Graphical abstract: Crystal structure of Ti(Ni,Pd)Hy hydrides in the I4/mmm space group. Highlights: Black-Right-Pointing-Pointer Neutron Diffraction and DFT calculations have been done on TiNi{sub 1-x}Pd{sub x}H{sub y} compounds. Black-Right-Pointing-Pointer Electronic effect of Pd substitution governs the hydrogenation properties in TiNi. Black-Right-Pointing-Pointer The rule of reverse stability in intermetallics/hydrides is observed with Pd substitution. Black-Right-Pointing-Pointer The hydrogen atoms in the I4/mmm structure prefer to occupy the 16n site.

  17. Increased conductivities of Cr doped Al2-xCrxO3 powders due to band gap narrowing

    NASA Astrophysics Data System (ADS)

    Badar, Nurhanna; Kamarulzaman, Norlida; Rusdi, Roshidah; Abdul Aziz, Nor Diyana; Kun Fun, Hoong

    2014-03-01

    A high Cr content in the synthesized Al2-xCrxO3 materials was achieved via a new synthesis route, the self propagating combustion method, for investigation of the effect of Cr substitution on the electrical, optical band gap and structural characteristics of the modified Al2O3 materials. X-ray diffraction (XRD) results showed that all the samples were pure and that Cr was successfully substituted in the crystal lattice. The cell parameters and volume are linearly dependent on the Cr content. AC impedance spectroscopy results show that conductivity of the Cr doped samples increases exponentially with Cr content. This is attributed to band gap narrowing of the Al2-xCrxO3 powders as obtained from UV-visible spectrophotometric studies.

  18. La2O3 Nano powders by mixture of fuels approach through chemical combustion for dielectric studies

    NASA Astrophysics Data System (ADS)

    Nithesh Sharma, G.; Venkateswara Rao, K.; Sesha Sai Kumar, V.; Shilpa Chakra, Ch; Rajendar, V.; Ranjith Reddy, P.

    2015-02-01

    La2O3 which is considered as a promising substitute for present SiO2 Gate oxide material in CMOS devices has been synthesized by mixture of fuel method . The method involves the mixing of the Lanthanum Nitrate with, mixture 1:1 of Urea and Glycine. The fuel to oxidizer ratio (?) has been maintained as 1.25. The powders were studied by several physical characterization techniques such as X-ray diffraction (XRD), Thermo gravimetric analysis (TGA) and Differential Thermal analysis (DTA) and dielectric properties have been studied using LCR meter. Surface morphology has been studied by SEM. Particle size has been analysed using Particle analyzer.

  19. Direct analysis of herbal powders by pipette-tip electrospray ionization mass spectrometry.

    PubMed

    Wang, Haixing; So, Pui-Kin; Yao, Zhong-Ping

    2014-01-27

    Conventional electrospray ionization mass spectrometry (ESI-MS) is widely used for analysis of solution samples. The development of solid-substrate ESI-MS allows direct ionization analysis of bulky solid samples. In this study, we developed pipette-tip ESI-MS, a technique that combines pipette tips with syringe and syringe pump, for direct analysis of herbal powders, another common form of samples. We demonstrated that various herbal powder samples, including herbal medicines and food samples, could be readily online extracted and analyzed using this technique. Various powder samples, such as Rhizoma coptidis, lotus plumule, great burdock achene, black pepper, Panax ginseng, roasted coffee beans, Fructus Schisandrae Chinensis and Fructus Schisandrae Sphenantherae, were analyzed using pipette-tip ESI-MS and quality mass spectra with stable and durable signals could be obtained. Both positive and negative ion modes were attempted and various compounds including amino acids, oligosaccharides, glycosides, alkaloids, organic acids, ginosensides, flavonoids and lignans could be detected. Principal component analysis (PCA) based on the acquired mass spectra allowed rapid differentiation of closely related herbal species. PMID:24418140

  20. Preparation of 1-Substituted Tetrahydro-?-carbolines by Lithiation-Substitution.

    PubMed

    Cochrane, Edward J; Hassall, Lorraine A; Coldham, Iain

    2015-06-01

    A method to prepare 1-substituted N-Boc-tetrahydro-?-carbolines was developed by lithiation followed by electrophilic substitution. The deprotonation to give the organolithium was optimized by in situ IR spectroscopy and showed that the Boc group rotates slowly at low temperature. The chemistry was applied to the synthesis of 9-methyleleagnine (N-methyltetrahydroharman) and 11-methylharmicine. PMID:25974712