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1

40 CFR 721.10011 - Barium calcium manganese strontium oxide.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

2012-07-01

2

40 CFR 721.10011 - Barium calcium manganese strontium oxide.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

2013-07-01

3

40 CFR 721.10011 - Barium calcium manganese strontium oxide.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

2011-07-01

4

40 CFR 721.10011 - Barium calcium manganese strontium oxide.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Barium calcium manganese strontium oxide. 721.10011 Section...Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance...substance identified as barium calcium manganese strontium oxide (PMN...

2014-07-01

5

40 CFR 721.10011 - Barium calcium manganese strontium oxide.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Barium calcium manganese strontium oxide. 721.10011...Chemical Substances § 721.10011 Barium calcium manganese strontium oxide. (a...chemical substance identified as barium calcium manganese strontium oxide (PMN...

2010-07-01

6

PHOTOSENSITIVE CENTERS AND CHARGE TRANSFER PROCESSES IN BARIUM CALCIUM TITANATE  

E-print Network

PHOTOSENSITIVE CENTERS AND CHARGE TRANSFER PROCESSES IN BARIUM CALCIUM TITANATE G.MALOVICHKO, V of crystals from barium titanate (BT) family make them promising candidates for various applications@uos.de; vgrachev@uos.de; schirmer@uos.de Abstract The results of the study of charge transfer processes in barium

Malovichko, Galina

7

Scattering lengths of calcium and barium isotopes  

SciTech Connect

We have calculated the s-wave scattering length of all the even isotopes of calcium (Ca) and barium (Ba) in order to investigate the prospect of Bose-Einstein condensation (BEC). For Ca we have used an accurate molecular potential based on detailed spectroscopic data. Our calculations show that Ca does not provide other isotopes alternative to the recently Bose condensed {sup 40}Ca that suffers strong losses because of a very large scattering length. For Ba we show by using a model potential that the even isotopes cover a broad range of scattering lengths, opening the possibility of BEC for at least one of the isotopes.

Dammalapati, U.; Willmann, L.; Knoop, S. [Kernfysisch Versneller Instituut (KVI), University of Groningen, Zernikelaan 25, 9747 AA Groningen (Netherlands); LaserLaB Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam (Netherlands)

2011-11-15

8

Scattering lengths of calcium and barium isotopes  

E-print Network

We have calculated the s-wave scattering length of all the even isotopes of calcium (Ca) and barium (Ba), in order to investigate the prospect of Bose-Einstein condensation (BEC). For Ca we have used an accurate molecular potential based on detailed spectroscopic data. Our calculations show that Ca does not provide other isotopes alternative to the recently Bose condensed 40Ca that suffers strong losses because of a very large scattering length. For Ba we show by using a model potential that the even isotopes cover a broad range of scattering lengths, opening the possibility of BEC for at least one of the isotopes.

U. Dammalapati; L. Willmann; S. Knoop

2011-10-25

9

21 CFR 582.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum calcium silicate. 582.2122 Section 582.2122...Anticaking Agents § 582.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2012-04-01

10

21 CFR 582.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Aluminum calcium silicate. 582.2122 Section 582.2122...Anticaking Agents § 582.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2010-04-01

11

21 CFR 182.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2009-04-01 true Aluminum calcium silicate. 182.2122 Section 182.2122...Anticaking Agents § 182.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2010-04-01

12

21 CFR 582.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aluminum calcium silicate. 582.2122 Section 582.2122...Anticaking Agents § 582.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2013-04-01

13

21 CFR 582.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aluminum calcium silicate. 582.2122 Section 582.2122...Anticaking Agents § 582.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2011-04-01

14

21 CFR 182.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aluminum calcium silicate. 182.2122 Section 182.2122...Anticaking Agents § 182.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2013-04-01

15

21 CFR 182.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum calcium silicate. 182.2122 Section 182.2122...Anticaking Agents § 182.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2012-04-01

16

21 CFR 182.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aluminum calcium silicate. 182.2122 Section 182.2122...Anticaking Agents § 182.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2011-04-01

17

21 CFR 582.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Aluminum calcium silicate. 582.2122 Section 582.2122...Anticaking Agents § 582.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2014-04-01

18

21 CFR 182.2122 - Aluminum calcium silicate.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Aluminum calcium silicate. 182.2122 Section 182.2122...Anticaking Agents § 182.2122 Aluminum calcium silicate. (a) Product. Aluminum calcium silicate. (b) Tolerance. 2...

2014-04-01

19

REMOVING BARIUM AND RADIUM THROUGH CALCIUM CATION EXCHANGE  

EPA Science Inventory

The removal of barium (Ba) and radium (Ra), which are found in many groundwater sources, was achieved in laboratory studies with an ion exchange process. In the studies, a strong acid resin in the calcium form effectively removed Ba(+2) and Ra (+2) to meet standards. The resin wa...

20

Structural, Spectral And Optical Characterization Of Calcium Barium Tartrate Crystals  

NASA Astrophysics Data System (ADS)

Single crystals of Calcium Barium tartrate (CBT) were grown by controlled diffusion in silica gel at ambient temperature. The structural characterization of the grown crystals was carried out by Powder X-ray diffraction analysis. The functional groups present in the crystals were identified using Fourier Transform Infrared spectral analysis. The UV-Vis-NIR transmission spectrum was recorded to study the optical transparency of the grown crystals.

Freeda, M. Mary; Priya, R. Krishna; Freeda, T. H.; Delphine, S. Mary

2011-10-01

21

Final Report on the Safety Assessment of Aluminum Silicate, Calcium Silicate, Magnesium Aluminum  

E-print Network

Final Report on the Safety Assessment of Aluminum Silicate, Calcium Silicate, Magnesium Aluminum dose of Zeolite A without any adverse reaction in the eye. Calcium Silicate had no discernible effect Silicate, Magnesium Silicate, Magnesium Trisilicate, Sodium Magnesium Silicate, Zirconium Silicate

Ahmad, Sajjad

22

Growth of nanofibrous barium carbonate on calcium carbonate seeds  

NASA Astrophysics Data System (ADS)

Fibrous barium carbonate (BaCO 3/witherite) crystals 50-100 nm in diameter and several microns in length were grown on calcium carbonate (CaCO 3) seeds at temperatures as low as 4 °C. The BaCO 3 fibers were deposited onto calcite rhombs or CaCO 3 films using the polymer-induced liquid-precursor (PILP) process, which was induced with the sodium salt of polyacrylic acid (PAA). The structure and morphology of the resultant fibers were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), and polarized light microscopy (PLM). Fibers were successfully grown on calcite seeds of various morphologies, with a range of barium concentrations, and PAA molecular weight and concentration. Two categories of fibers were grown: straight and twisted. Both types of fibers displayed single-crystalline SAED diffraction patterns, but after examining high-resolution TEM lattice images, it was revealed that the fibers were in fact made up of nanocrystalline domains. We postulate that these nanocrystalline domains are well aligned due to a singular nucleation event (i.e., each fiber propagates from a single nucleation event on the seed crystal) with the nanocrystalline domains resulting from stresses caused by dehydration during crystallization of the highly hydrated precursor phase. These BaCO 3 fibers grown on calcite substrates further illustrate the robustness and non-specificity of the PILP process.

Homeijer, Sara J.; Olszta, Matthew J.; Barrett, Richard A.; Gower, Laurie B.

2008-05-01

23

Utilization of aluminum sludge and aluminum slag (dross) for the manufacture of calcium aluminate cement  

Microsoft Academic Search

Four calcium aluminate cement mixes were manufactured from aluminum sludge as a source of calcium oxide and Al2O3 and aluminum slag (dross) as a source of aluminum oxide with some additions of pure alumina. The mixes were composed of 35–50% aluminum sludge, 37.50–48.75% aluminum slag (dross) and 12.50–16.25% aluminum oxide. The mixed were processed then sintered at different firing temperatures

E. M. M. Ewais; N. M. Khalil; M. S. Amin; Y. M. Z. Ahmed; M. A. Barakat

2009-01-01

24

Life Model of Hollow Cathodes Using a Barium Calcium Aluminate Impregnated Tungsten Emitter  

NASA Technical Reports Server (NTRS)

Hollow cathodes with barium calcium aluminate impregnated tungsten emitters for thermionic emission are widely used in electric propulsion. These high current, low power cathodes are employed in ion thrusters, Hall thrusters, and on the International Space Station in plasma contactors. The requirements on hollow cathode life are growing more stringent with the increasing use of electric propulsion technology. The life limiting mechanism that determines the entitlement lifetime of a barium impregnated thermionic emission cathode is the evolution and transport of barium away from the emitter surface. A model is being developed to study the process of barium transport and loss from the emitter insert in hollow cathodes. The model accounts for the production of barium through analysis of the relevant impregnate chemistry. Transport of barium through the approximately static gas is also being treated. Finally, the effect of temperature gradients within the cathode are considered.

Kovaleski, S. D.; Burke, Tom (Technical Monitor)

2001-01-01

25

The thermophysical properties of calcium and barium zirconium phosphate  

NASA Astrophysics Data System (ADS)

The thermophysical and structural properties of calcium and barium zirconium phosphate ceramics (CZP and BZP) have been investigated for their potential candidacy as actinide hosts for inert matrix fuels (IMF) in nuclear reactors. These phosphate ceramics, which can accommodate minor actinides as well as the resulting fission products, are found to be thermally stable to 1600 °C in air, however they begin to decompose in an inert atmosphere above approximately 1400 °C. The heat capacity, thermal conductivity and bulk thermal-expansion were measured from room temperature up to 1200 °C. Structural changes in this temperature region as well as the anisotropic thermal-expansion behaviour were studied using high-temperature X-ray diffraction. A phase change from R-3 to R-3c was identified for Ba0.5Zr2(PO4)3 near 880 °C. The thermal conductivity for these ceramics at 1000 °C was found to be 1.0 W m-1 K-1, a relatively low thermal conductivity that was increased to 5.0 W m-1 K-1 at 1000 °C for BZP:Ni (25:75 mass ratio) cermet composites.

Gregg, Daniel J.; Karatchevtseva, Inna; Triani, Gerry; Lumpkin, Gregory R.; Vance, Eric R.

2013-10-01

26

Barium oxide, calcium oxide, magnesia, and alkali oxide free glass  

DOEpatents

A glass composition consisting essentially of about 10-45 mole percent of SrO; about 35-75 mole percent SiO.sub.2; one or more compounds from the group of compounds consisting of La.sub.2O.sub.3, Al.sub.2O.sub.3, B.sub.2O.sub.3, and Ni; the La.sub.2O.sub.3 less than about 20 mole percent; the Al.sub.2O.sub.3 less than about 25 mole percent; the B.sub.2O.sub.3 less than about 15 mole percent; and the Ni less than about 5 mole percent. Preferably, the glass is substantially free of barium oxide, calcium oxide, magnesia, and alkali oxide. Preferably, the glass is used as a seal in a solid oxide fuel/electrolyzer cell (SOFC) stack. The SOFC stack comprises a plurality of SOFCs connected by one or more interconnect and manifold materials and sealed by the glass. Preferably, each SOFC comprises an anode, a cathode, and a solid electrolyte.

Lu, Peizhen Kathy; Mahapatra, Manoj Kumar

2013-09-24

27

Effect of chloride incorporation on the crystallization of zirconium-barium-lanthanum-aluminum fluoride glass  

NASA Technical Reports Server (NTRS)

One aspect of the influence of preparation procedure on the crystallization behavior of a zirconium-barium-lanthanum-aluminum fluoride glass was studied. The crystallization pattern of this glass may be affected by the chlorine concentration within it. In particular, when such glasses are heated at low temperatures, the alpha-Ba-Zr-F6 crystalline phase forms only in those glasses which contain chloride.

Neilson, G. F.; Smith, G. L.; Weinberg, M. C.

1985-01-01

28

THE ABSORPTION OF CALCIUM, STRONTIUM, BARIUM AND RADIUM FROM THE GASTROINTESTINAL TRACT OF THE RAT  

Microsoft Academic Search

The absorption of Ca, Sr, Ba, and Ra from the gastrointestinal tract of ; the rat was studied by means of double radioactive tracer techniques. At 14-18 ; days of age there is almost complete absorption of calcium and strontium and ; about 80% of barium and radium is absorbed. For animals 6- 8-weeks old ; absorption of Ca decreased

D. M. Taylor; P. H. Bligh; M. H. Duggan

1962-01-01

29

Precipitation of Calcium, Magnesium, Strontium and Barium in Tissues of Four Acacia Species (Leguminosae: Mimosoideae)  

PubMed Central

Precipitation of calcium in plants is common. There are abundant studies on the uptake and content of magnesium, strontium and barium, which have similar chemical properties to calcium, in comparison with those of calcium in plants, but studies on co-precipitation of these elements with calcium in plants are rare. In this study, we compared morphologies, distributional patterns, and elemental compositions of crystals in tissues of four Acacia species grown in the field as well as in the glasshouse. A comparison was also made of field-grown plants and glasshouse-grown plants, and of phyllodes of different ages for each species. Crystals of various morphologies and distributional patterns were observed in the four Acacia species studied. Magnesium, strontium and barium were precipitated together with calcium, mainly in phyllodes of the four Acacia species, and sometimes in branchlets and primary roots. These elements were most likely precipitated in forms of oxalate and sulfate in various tissues, including epidermis, mesophyll, parenchyma, sclerenchyma (fibre cells), pith, pith ray and cortex. In most cases, precipitation of calcium, magnesium, strontium and barium was biologically induced, and elements precipitated differed between soil types, plant species, and tissues within an individual plant; the precipitation was also related to tissue age. Formation of crystals containing these elements might play a role in regulating and detoxifying these elements in plants, and protecting the plants against herbivory. PMID:22848528

He, Honghua; Bleby, Timothy M.; Veneklaas, Erik J.; Lambers, Hans; Kuo, John

2012-01-01

30

Calcium barium niobate as a functional material for broadband optical frequency conversion.  

PubMed

We demonstrate the application of as-grown calcium barium niobate (CBN) crystal with random-sized ferroelectric domains as a broadband frequency converter. The frequency conversion process is similar to broadband harmonic generation in commonly used strontium barium niobate (SBN) crystal, but results in higher conversion efficiency reflecting a larger effective nonlinear coefficient of the CBN crystal. We also analyzed the polarization properties of the emitted radiation and determined the ratio of d32 and d33 components of the second-order susceptibility tensor of the CBN crystal. PMID:24690779

Sheng, Yan; Chen, Xin; Lukasiewicz, Tadeusz; Swirkowicz, Marek; Koynov, Kaloian; Krolikowski, Wieslaw

2014-03-15

31

Interaction Studies Between Crofer-22APU Alloy And P2O5 Containing Barium Calcium Alumino-borosilicate (BCABS) Sealant Glass-Ceramics  

NASA Astrophysics Data System (ADS)

We present the effect of P2O5 addition on barium calcium aluminum borosilicate BCABS glasses of composition (mol %) 35BaO-15CaO-5Al2O3-(37-x)SiO2-8B2O3-xP2O5 (0?x?5). The incorporation of P2O5 increased network polymerization and crystallization tendency. However, addition of P2O5 leads to the formation of Cr2O3 at the interface, saturating it in the ions of the metal. This improves glass-to-metal bonding.

Ananthanarayanan, A.; Montagne, L.; Revel, B.; Kothiyal, G. P.

2010-12-01

32

Calcium citrate without aluminum antacids does not cause aluminum retention in patients with functioning kidneys  

NASA Technical Reports Server (NTRS)

It has been suggested that calcium citrate might enhance aluminum absorption from food, posing a threat of aluminum toxicity even in patients with normal renal function. We therefore measured serum and urinary aluminum before and following calcium citrate therapy in patients with moderate renal failure and in normal subjects maintained on constant metabolic diets with known aluminum content (967-1034 mumol/day, or 26.1-27.9 mg/day, in patients and either 834 or 1579 mumol/day, or 22.5 and 42.6 mg/day, in normal subjects). Seven patients with moderate renal failure (endogenous creatinine clearance of 43 ml/min) took 50 mmol (2 g) calcium/day as effervescent calcium citrate with meals for 17 days. Eight normal women received 25 mmol (1 g) calcium/day as tricalcium dicitrate tablets with meals for 7 days. In patients with moderate renal failure, serum and urinary aluminum were normal before treatment at 489 +/- 293 SD nmol/l (13.2 +/- 7.9 micrograms/l) and 767 +/- 497 nmol/day (20.7 +/- 13.4 micrograms/day), respectively. They remained within normal limits and did not change significantly during calcium citrate treatment (400 +/- 148 nmol/l and 600 +/- 441 nmol/day, respectively). Similarly, no significant change in serum and urinary aluminum was detected in normal women during calcium citrate administration (271 +/- 59 vs 293 +/- 85 nmol/l and 515 +/- 138 vs 615 +/- 170 nmol/day, respectively). In addition, skeletal bone aluminum content did not change significantly in 14 osteoporotic patients (endogenous creatinine clearance of 68.5 ml/min) treated for 24 months with calcium citrate, 10 mmol calcium twice/day separately from meals (29.3 +/- 13.9 ng/mg ash bone to 27.9 +/0- 10.4, P = 0.727). In them, histomorphometric examination did not show any evidence of mineralization defect. Thus, calcium citrate given alone without aluminum-containing drugs does not pose a risk of aluminum toxicity in subjects with normal or functioning kidneys, when it is administered on an empty stomach at a recommended dose of 20 mmol calcium/day.

Sakhaee, K.; Wabner, C. L.; Zerwekh, J. E.; Copley, J. B.; Pak, L.; Poindexter, J. R.; Pak, C. Y.

1993-01-01

33

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

Microsoft Academic Search

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

B. O. Fowler

1974-01-01

34

Nanoparticles for cultural heritage conservation: calcium and barium hydroxide nanoparticles for wall painting consolidation.  

PubMed

Nanotechnology provides new concepts and materials for the consolidation and protection of wall paintings. In particular, humble calcium and barium hydroxide nanoparticles offer a versatile and highly efficient tool to combat the main degradation processes altering wall paintings. Clear example of the efficacy and potentiality of nanotechnology is represented by the conservation in situ of Maya wall paintings in the archaeological area in Calakmul (Mexico). PMID:20658506

Giorgi, Rodorico; Ambrosi, Moira; Toccafondi, Nicola; Baglioni, Piero

2010-08-16

35

Magnetic behavior and dielectric properties of aluminum substituted M-type barium hexaferrite  

NASA Astrophysics Data System (ADS)

Various parameters in the structural features of the aluminum substituted barium hexagonal ferrite particles BaAlxFe12-xO19 with 0?x?3.5 which were prepared by the solid state reaction method have been studied. The infrared transmission spectrum was measured in the wave number region 5000-200 cm-1 at room temperature. The results were interpreted in terms of the vibrations of the isolated molecular units in such a way to preserve the tetrahedral and octahedral clusters of metal oxides in the barium aluminum hexagonal ferrites. The infrared features are assigned to Fe-O and Ba-O bonds in M-type hexagonal ferrite (BaFe12O19) molecules. Also, the results explain the structural model, based on the effect of aluminum substitution “Al-O bond”. On the other hand, the magnetic behavior of the samples was studied using the vibrating sample magnetometer technique. The saturation magnetization (Ms) and magneton number (nB) decrease with increasing Al3+ substitution from 61.2 to 28.9 emu/g and from 12.2 to 5.3 ?B respectively. Also, all samples were characterized using X-ray diffraction and the values of grain size, microstrain and dislocation density of all samples were calculated. The dielectric parameters and ac conductivity measurements were performed within a temperature range 293-493 K. The ac conductivity showed a linear relation with the frequency power law with an exponent s?0.69-0.14 for BaFe12O19. It decreases with increasing temperature, indicating that the heterogeneous structures increase. While the dielectric constant (??) and the dielectric loss (??) decrease with increasing Al substitution.

El-Sayed, S. M.; Meaz, T. M.; Amer, M. A.; El Shersaby, H. A.

2013-10-01

36

Potassium-induced depolarizations and generation of tension in barnacle muscle fibres: effects of external calcium, strontium and barium.  

PubMed

Potassium-induced contractions were studied in muscle fibres from Megabalanus psittacus (Darwin) in an attempt to establish the requirement of extracellular calcium for the development of force. A sudden elevation of external potassium induced the production of contractures and/or twitches only if calcium was present. In calcium-free solutions no contraction or action potential occurred. When external calcium was replaced by barium, potassium-induced depolarizations accompanied by several action potentials did not generate either contractures or twitches. With strontium in place of calcium, action potentials of different duration were observed. Only the long-lasting ones (a few seconds) induced twitches. PMID:6729014

Luxoro, M; Nassar-Gentina, V

1984-04-01

37

Efficient ionisation of calcium, strontium and barium by resonant laser pumping  

NASA Technical Reports Server (NTRS)

Efficient ionization has been observed when an atomic vapor of strontium, barium or calcium was illuminated with a long pulse tunable laser at the frequency of the atomic resonance line. The variation in the degree of ionization with neutral density and laser intensity has been measured using the 'hook' method. The maximum ionization observed was 94%. Excited state populations were measured yielding an excitation temperature (depending on exact experimental conditions) in the region of 0.4 eV. The decay of ion density after the laser pulse was monitored and the recombination coefficients determined. The results are interpreted in terms of an electron heating model.

Skinner, C. H.

1980-01-01

38

Incorporation of Short-Lived Be in a Calcium-Aluminum  

E-print Network

Incorporation of Short-Lived 10 Be in a Calcium-Aluminum­ Rich Inclusion from the Allende Meteorite Kevin D. McKeegan,1 * Marc Chaussidon,2 Franc¸ois Robert3 Enrichments in boron-10/boron-11 in a calcium-aluminum canonical abundance of aluminum-26 may still require seeding of the solar system by radioactive stellar

39

The retention of calcium, barium, and strontium ions by a mollisol humic acid: Spectroscopic investigation  

NASA Astrophysics Data System (ADS)

Humic substances have a major role in controlling the mobility and bioavailability of metallic ions in soils and natural waters. The alkaline earth metals, calcium, barium, and strontium, are broadly abundant in the crust of the earth, and Ca2+ ions are known to be important in the formation of structural aggregates in soils. Yet, direct spectroscopic evidence of how Ca, Ba, and Sr ions interact with soil organic matter, is minimal. To develop a deeper understanding of the interaction of the alkaline earth cations in soil, we studied the complexation behavior of strontium, barium and calcium by humic acid (HA) using solid-state 13C CP-MAS NMR, FTIR and extended x-ray absorption fine structure (EXAFS) spectroscopy. A HA sample was extracted from an agricultural mollisol (pH 6, 32.5% clay content, 3.7% organic carbon) located in southwestern Minnesota, USA, by the standard NaOH method. The HA sample was treated with chloride salts of Ca, Sr or Ba, then freeze-dried prior to spectroscopic measurements. The FTIR spectra, obtained using pressed KBr disks, and the 13C NMR spectra revealed spectral differences, stemming mainly from deprotonation reactions of the carboxylic and phenolic groups of the HA. The association of Ca, Ba, and Sr ions with the HA caused a marked FTIR shift of the carboxylate band, with the Ba shift being the most pronounced (HA 1604.7; HA-Ca 1595.1; HA-Sr 1597; HA-Ba 1579.6), which seems to imply that Ba is the strongest bound element. An NMR shift of the carbonyl peak at 171.8 ppm was also observed to 174.5 for Ca, 173.7 for Sr, and 174.4 for Ba confirming that these cations are behaving differently towards soil HA. The EXAFS spectra indicated back-scattering from oxygen atoms, in the first shell, for Ca, Sr, and Ba with varied coordination number. Our data prove that (1) the carboxylates and phenolates are the prevailing functional groups involved in the interactions between the extracted HA and alkali metal cations, (2) barium forms the strongest complex compared to strontium and calcium.

Oufqir, Sofia; Bloom, Paul R.; Torner, Brandy M.

2014-05-01

40

Interaction Studies Between Crofer-22APU Alloy And P{sub 2}O{sub 5} Containing Barium Calcium Alumino-borosilicate (BCABS) Sealant Glass-Ceramics  

SciTech Connect

We present the effect of P{sub 2}O{sub 5} addition on barium calcium aluminum borosilicate BCABS glasses of composition (mol %)35BaO-15CaO-5Al{sub 2}O{sub 3}-(37-x)SiO{sub 2}-8B{sub 2}O{sub 3}-xP{sub 2}O{sub 5}(0{<=}x{<=}5). The incorporation of P{sub 2}O{sub 5} increased network polymerization and crystallization tendency. However, addition of P{sub 2}O{sub 5} leads to the formation of Cr{sub 2}O{sub 3} at the interface, saturating it in the ions of the metal. This improves glass-to-metal bonding.

Ananthanarayanan, A. [Technical Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); UCCS-Unite de Catalyse et Chimie du Solide-UMR CNRS 8181, Ecole Nationale Superieure de Chimie de Lille, Universite des Sciences et Technologies de Lille, BP 108, 59562 Villeneuve d'Ascq Cedex (France); Montagne, L.; Revel, B. [UCCS-Unite de Catalyse et Chimie du Solide-UMR CNRS 8181, Ecole Nationale Superieure de Chimie de Lille, Universite des Sciences et Technologies de Lille, BP 108, 59562 Villeneuve d'Ascq Cedex (France); Kothiyal, G. P. [Technical Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2010-12-01

41

Intra-grain composition nonuniform barium strontium calcium titanate ceramics by sol-gel pervasion techniques  

NASA Astrophysics Data System (ADS)

The use of ferroelectric ceramics in microwave devices requires that they possess low-loss, frequency-stable and highly tunable properties. The problems of traditional barium strontium calcium titanate ceramics are higher loss and inappropriate work temperature dependence. In this work, a conventional mixed oxide route was used to prepare BaTiO3, SrTiO3 and CaTiO3 precursor powders. The BaTiO3, SrTiO3 and CaTiO3 powders were thoroughly ball mill mixed. They were then added to 5 wt% polyvinyl alcohol and pressed under a uni-axial pressure of 220 MPa into discs of 12 mm diameter. We introduced nano-grains of barium strontium titanate (BST) into the BSCT ceramic by nano-grain pervasion techniques to fabricate compositionally nonuniform BSCT ceramic samples. The nano-particles of BST are prepared with the sol-gel method. The sol-gel was subjected to ultrasonic irradiation and then vacuum methods in order to easily introduce nanoparticles into bulky BSCT. The ceramics do not show a sharp change in the dielectric constant and have a wide range of Curie temperature distribution. This is attributed to the presence of a compositionally nonuniform micro-area in the samples. Compared with uniform-composition BSCT, compositionally nonuniform BSCT has favourable dielectric properties. These results suggest that the compositionally nonuniform BSCT ceramics are promising candidates as tunable microwave elements.

Xu, Honghai; Jin, Dengren; Wu, Wenbiao; Cheng, Jinrong

2009-03-01

42

Reactions of calcium orthosilicate and barium zirconate with oxides and sulfates of various elements  

NASA Technical Reports Server (NTRS)

Calcium orthosilicate and barium zirconate were evaluated as the insulation layer of thermal barrier coatings for air cooled gas turbine components. Their reactions with various oxides and sulfates were studied at 1100 C and 1300 C for times ranging up to 400 and 200 hours, respectively. These oxides and sulfates represent potential impurities or additives in gas turbine fuels and in turbine combustion air, as well as elements of potential bond coat alloys. The phase compositions of the reaction products were determined by X-ray diffraction analysis. BaZrO3 and 2CaO-SiO2 both reacted with P2O5, V2O5, Cr2O3, Al2O3, and SiO2. In addition, 2CaO-SiO2 reacted with Na2O, BaO, MgO, and CoO and BaZrO3 reacted with Fe2O3.

Zaplatynsky, I.

1979-01-01

43

ALUMINUM ALTERS CALCIUM TRANSPORT IN PLASMA MEMBRANE AND ENDOPLASMIC RETICULUM FROM RAT BRAIN  

EPA Science Inventory

Calcium is actively transported into intracellular organelles and out of the cytoplasm by Ca2+/Mg2+-ATPases located in the endoplasmic reticulum and plasma membranes. he effects of aluminum on calcium transport were examined in the adult rat brain. 5Ca-uptake was examined in micr...

44

Interaction of barium oxyfluorochloride melts with refractories based on aluminum and magnesium oxides  

NASA Astrophysics Data System (ADS)

The contact surface of oxyfluorochloride melts containing 20-40 wt % BaO with Al2O3, MgO, or MgO · Al2O3 ceramics is studied by laser emission microspectral analysis in the course of melting of complexly alloyed nickel alloys in vacuo. The distribution profiles of barium in a crucible material are determined at different chemical compositions of a slag and ceramics to a depth of 800 ?m. The diffusion coefficient of barium D Ba is calculated and ranges from 0.45 × 10-5 to 5.8 × 10-5 cm2/s. A tendency for increasing D Ba in experiments with the Al2O3 ceramics and an insignificant decrease of D Ba in experiments with ceramics of another composition is observed with an increase in the weight fraction of BaO (to 40 wt %).

Burtsev, V. T.; Sidorov, V. V.; Rigin, V. E.

2014-11-01

45

Substitution of Calcium Carbonate for Aluminum Hydroxide in Patients on Hemodialysis  

Microsoft Academic Search

Substitution of calcium carbonate for aluminum hydroxide in patients on dialysis: effects on acidosis, parathyroid function, and calcemia. We studied the effects of substituting CaCO3 for aluminum-containing gels on metabolic acidosis and on the response of the parathyroid glands in 11 patients treated with chronic hemodialysis. The 8 men and 3 women were clinically stable, were known to be compliant,

Adriana Anelli; Diego Brancaccio; Rosaria Damasso; Paola Padovese; Maurizio Gallieni; Serafino Garella

1989-01-01

46

IMPLICATIONS OF THE CALCIUM-ALUMINUM EXCHANGE SYSTEM FOR THE EFFECT OF ACID PRECIPITATION ON SOILS  

EPA Science Inventory

Calcium-aluminum exchange isotherms were generated for three common ion exchange equilibrium equations, and their implications relative to the probable effects of acid rainfall are examined. The equations examined were those of Gaines and Thomas (1953), Vanselow (1932), and Gapon...

47

Effect of calcium carbonate and aluminum hydroxide on human intestinal function  

Microsoft Academic Search

The effect of calcium carbonate (6 g daily) and of aluminum hydroxide (Amphojel, 7.2 g daily) on human gastrointestinal function was examined because these popular antacids have a documented effect on fecal fat, an undocumented association with constipation, and a putative ability to ameliorate cocarcinogenic effects of bile acids and fatty acids on colonic mucosa. Intake-output studies were conducted over

David Saunders; Jim Sillery; Roger Chapman

1988-01-01

48

Calcium-Aluminum-rich Inclusions in Chondritic Meteorites  

NASA Astrophysics Data System (ADS)

Calcium-aluminum-rich inclusions (CAIs) are submillimeter- to centimeter-sized clasts in chondritic meteorites, whose ceramic-like chemistry and mineralogy set them apart from other chondrite components. Since their first descriptions more than 30 years ago (e.g., Christophe Michel-Lévy, 1968), they have been the objects of a vast amount of study. At first, interest centered on the close similarity of their mineralogy to the first phases predicted by thermodynamic calculations to condense out of a gas of solar composition during cooling from very high temperatures (e.g., Lord, 1965; Grossman, 1972). Immediately thereafter, CAIs were found to be extremely old (4.56 Ga) and to possess unusual isotopic compositions (in particular, in magnesium and oxygen) suggestive of a presolar dust component. In short, they appear to be the oldest and most primitive objects formed in the infant solar system.In the late 1980s (e.g., MacPherson et al., 1988), the attention of most workers in the field was focused on understanding the petrogenesis and isotopic compositions of CAIs within a relatively restricted number of chondrite varieties. Much has changed since then. We now have extended our data sets beyond CV and CM chondrites to CAIs from ordinary, enstatite, and a wider range of carbonaceous chondrites. Out of this has emerged an ironic fact: the large centimeter-sized CAI "marbles" (the so-called type Bs; see below) that are so prominent in CV chondrites, and upon which so many of the original concepts were based owing to the abundance and availability of material from the Allende meteorite, turn out to be the exceptions rather than the norm. Indeed, we now know that the Allende parent body itself experienced so much postaccretion reprocessing that its CAIs reveal only a murky picture of the early solar nebula. Another profound change since 1988 has been the development of ion microprobe technology permitting microanalysis of oxygen isotopes within standard petrographic thin sections. One of the debates raging in 1988 centered on the difficulty of making CAIs at the distance of the asteroid belt where the host chondrites presumably accreted. Since then, a combination of isotopic (especially beryllium-boron and oxygen) evidence and theoretical modeling have suggested the interesting possibility that CAIs all formed very close to the infant sun and were later dispersed out to the respective chondrite accretion regions. Yet another difference from 1988 is that the science of meteoritics has matured past the point where workers study CAIs without consideration of other chondritic components, most notably chondrules. Bulk composition differences aside, CAIs and chondrules are both products of very high temperature events in the earliest solar system. Like chondrules, many CAIs apparently solidified from partially to completely molten droplets. Moreover, chondrules and CAIs both have far more complex histories than was generally recognized in the late 1980s: both may have experienced multiple melting episodes, followed by prolonged nebular and/or asteroidal modification due to gaseous or liquid interactions and reheating as a result of shock processes. In short, although CAIs are still recognized as being the oldest objects formed in our solar system and possessing isotopic traces of the presolar dust from which they ultimately formed, they are a long way from being the primitive condensates they were once thought to be. Rather than stressing the unusual isotopic characteristics of CAIs and the presolar implications, this chapter will instead treat CAIs as probes of the earliest solar system that reveal the nature of the high-temperature events, their chronology, and the likely locales where such events occurred.This chapter is not, and does not pretend to be, an exhaustive review of the sum of knowledge about CAIs. Indeed, so much new data have been generated since 1988, especially isotopic data from an ever-growing number of sophisticated ion microprobe labs, that it would far beyond the space limitations of this chapter to a

MacPherson, G. J.

2003-12-01

49

RenaGel®, a nonabsorbed calcium- and aluminum-free phosphate binder, lowers serum phosphorus and parathyroid hormone  

Microsoft Academic Search

RenaGel®, a nonabsorbed calcium- and aluminum-free phosphate binder, lowers serum phosphorus and parathyroid hormone.Background.This multicenter, open-label, dose-titration study assessed the safety and efficacy of RenaGel®, a nonabsorbed calcium- and aluminum-free phosphate binder, in lowering serum phosphorus. Secondary outcomes were its effects on serum intact parathyroid hormone (iPTH) and serum lipids.Methods.Phosphate binders were discontinued during a two-week washout period. Patients whose

EDUARDO A SLATOPOLSKY; STEVEN K BURKE; MAUREEN A DILLON

1999-01-01

50

Physicochemical prediction of the types of nonmetallic inclusions: Complex deoxidation of steel with aluminum and calcium  

Microsoft Academic Search

The complex deoxidation of steel with aluminum and calcium is used as an example to analyze the state of the art in the methods\\u000a of physicochemical prediction of the types of nonmetallic inclusions forming during ladle treatment of steel. The uncertainty\\u000a existing in the thermodynamic description of the simplest object of metallurgical technologies, i.e., iron-based dilute liquid\\u000a solutions, is shown

E. Kh. Shakhpazov; A. I. Zaitsev; N. G. Shaposhnikov; I. G. Rodionova; N. A. Rybkin

2006-01-01

51

Use of calcium\\/aluminum ratios as indicators of stress in forest ecosystems  

Microsoft Academic Search

The calcium\\/aluminum (Ca\\/Al) molar ratio of the soil solution provides a valuable measurement endpoint or ecological indicator for identification of approximate thresholds beyond which the risk of forest damage from Al stress and nutrient imbalances increases. The Ca\\/Al ratio can also be used as an indicator to assess forest ecosystem changes over time in response to acidic deposition, forest harvesting,

Christopher S. Cronan; David F. Grigal

1995-01-01

52

Imaging of calcium and aluminum in neurofibrillary tangle-bearing neurons in parkinsonism-dementia of Guam.  

PubMed Central

We report the distribution and imaging of calcium and aluminum in neurofibrillary tangle (NFT)-bearing neurons within Sommer's sector of the hippocampus in Guamanian patients with parkinsonism-dementia, using a method of computer-controlled electron beam x-ray micro-analysis and wavelength dispersive spectrometry. Calcium and aluminum were distributed in cell bodies and axonal processes of NFT-bearing neurons. The elemental images show that both calcium and aluminum deposits occur within the same NFT-bearing hippocampal neuron in this dementing disease, suggesting that these elements are involved in NFT formation. No prominent concentrations of calcium and aluminum were imaged in non-NFT-containing regions within the pyramidal cell layer of the parkinsonism-dementia cases or in the control cases. These findings support the hypothesis that secondary hyperparathyroidism resulting from low environmental calcium and magnesium in the high-incidence focus of amyotrophic lateral sclerosis and parkinsonism-dementia on Guam had led to abnormal deposition of calcium and aluminum in the central nervous system. Images PMID:6584922

Garruto, R M; Fukatsu, R; Yanagihara, R; Gajdusek, D C; Hook, G; Fiori, C E

1984-01-01

53

Substitution of calcium carbonate for aluminum hydroxide in patients on hemodialysis. Effects on acidosis, on parathyroid function, and on calcemia.  

PubMed

Substitution of calcium carbonate for aluminum hydroxide in patients on dialysis: effects on acidosis, parathyroid function, and calcemia. We studied the effects of substituting CaCO3 for aluminum-containing gels on metabolic acidosis and on the response of the parathyroid glands in 11 patients treated with chronic hemodialysis. The 8 men and 3 women were clinically stable, were known to be compliant, and had no clinical evidence of aluminum overload; they were not receiving vitamin D supplements; and they had been on dialysis for an average of 65.6 months (range: 13-188 months). After 3 weeks of CaCO3 administration plasma phosphate concentration remained well controlled, and plasma calcium concentration increased from 9.2 +/- 0.2 (2.3 +/- 0.1 mmol/l) to 10.1 +/- 0.2 mg/dl (2.5 +/- 0.1 mmol/l). Predialysis plasma bicarbonate concentration increased from 19.7 +/- 0.6 to 21.9 +/- 0.6 mmol/l. Plasma aluminum concentration decreased from 78.7 +/- 12.5 to 48.5 +/- 3.9 micrograms/l. Plasma PTH level increased from 2.0 +/- 0.7 to 3.3 +/- 0.8 ng/ml despite the concurrent increase in plasma calcium levels. All values returned to control levels following discontinuation of CaCO3 and resumption of aluminum gels. We conclude: (1) In addition to controlling hyperphosphatemia and increasing plasma calcium concentration, CaCO3 ameliorates metabolic acidosis. (2) Avoidance of oral aluminum intake is followed by prompt lowering of plasma aluminum levels. (3) PTH levels paradoxically increase despite the increment in plasma calcium concentration. The hypercalcemia seen with CaCO3 administration may be due, in part, to transient parathyroid hypersecretion that develops when aluminum administration is discontinued. PMID:2500612

Anelli, A; Brancaccio, D; Damasso, R; Padovese, P; Gallieni, M; Garella, S

1989-01-01

54

Aluminum diffusion in Oxisols as influenced by soil water matric potential, ph, lime, gypsum, potassium chloride, and calcium phosphate  

Microsoft Academic Search

Plant root exposure to soil aluminum (Al) depends on the soil solution Al concentration and transport to the root by diffusion. Changes in Al diffusive flux for two Oxisols was measured under laboratory conditions as a function of pH, water matric potential, and applications of gypsum, potassium chloride, and calcium phosphate. Double?faced cation exchange resin sheets served as sinks for

F. H. T. Oliveira; R. F. Novais; T. J. Smyth; J. C. L. Neves

2000-01-01

55

TUNGSTEN AND HAFNIUM DISTRIBUTION IN CALCIUM-ALUMINUM INCLUSIONS (CAIs) FROM ALLENDE AND EFREMOVKA. M. Humayun1  

E-print Network

TUNGSTEN AND HAFNIUM DISTRIBUTION IN CALCIUM-ALUMINUM INCLUSIONS (CAIs) FROM ALLENDE AND EFREMOVKA with, or even earlier than, metal from CAIs and chondrules [3]. Tungsten isotope compositions represent veins [5]. Tungsten mobility is cause for concern, but is not sufficient evidence against the Kleine et

Grossman, Lawrence

56

An Isotopic and Petrologic Study of Calcium-Aluminum-Rich Inclusions from CO3 Meteorites  

NASA Astrophysics Data System (ADS)

We have studied the mineralogy and petrology of 229 calcium-aluminum-rich inclusions (CAIs) from ten CO3 meteorites of petrologic types 3.0-3.7. Subsets of these inclusions were measured by ion probe for magnesium, calcium, and titanium isotopes and REE abundances. Most CAIs from CO3 meteorites fall into three major types: (1) melilite-rich inclusions, which also contain spinel/hercynite, perovskite, and occasionally hibonite; (2) spinel-pyroxene inclusions; and (3) hibonite-hercynite inclusions. In addition, several isolated hibonite grains, two grossite (CaAl 4O 7) bearing CAIs, two hibonite-fassaite microspherules, and one anorthite-spinel-pyroxene inclusion were found. CAIs from CO3 meteorites exhibit all of the REE patterns commonly seen in inclusions from CV3 and CM2 chondrites. Most exhibit evidence of 26Al, and many have inferred ( 26Al/ 27Al) o ? 5 × 10 -5. The relative abundances of different types of CAIs in CO3 chondrites differ from those in CV3 and CM2 chondrites. CAIs in CO3 chondrites have experienced considerable secondary alteration, both before and after accretion. Signatures of nebular alteration include Wark-Lovering rims and the high Fe contents in spinels from all hibonite/hercynite inclusions. Occasionally, melilite and anorthite show evidence of nebular alteration to feldspathoids and pyroxene. The magnesium-aluminum systematics of some melilite-rich inclusions were apparently disturbed prior to final accretion of the parent body. Parent body alteration is indicated by correlations between CAI characteristics and the petrologic type of the host meteorite. Spinel in melilite-rich and coarse-grained spinel-pyroxene inclusions becomes more Fe rich, with the development of relatively homogeneous hercynitic spinel (˜50-60 mol%) in CAIs from metamorphic grades >3.4. Perovskite has been converted to ilmenite in types >3.4. Melilite-rich inclusions are abundant in CO3.0-3.3 meteorites, rare in 3.4 meteorites, and absent meteorites of types 3.5-3.7; melilite-rich CAIs are probably replaced by inclusions rich in feldspathoids, pyroxene, and Fe-rich spinel. Isotopic disturbance of the magnesium-aluminum systematics may be more severe in higher petrologic types. Hibonite seems to be unaffected by this level of metamorphism. Three isotopically unusual inclusions were found. One single-crystal hibonite, Isna SP16, has a REE pattern strongly depleted in Ce and Y, ( 26Al/ 27Al) o = (2.4 ± 0.3) × 10 -5, and mass fractionated calcium (F Ca = +12 ± 2‰/amu), but no resolvable nuclear anomalies in neutron-rich calcium isotopes. The REE pattern, which is thought to reflect nebular conditions, and mass-fractionated calcium, indicative of evaporation, are similar to those of the FUN inclusion, HAL, and related hibonites, indicating similar formation conditions. The absence in Isna SP16 of the nuclear anomalies observed in HAL and the difference in ( 26Al/ 27Al) o between HAL and Isna SP16 indicate that the processes that produced HAL-type hibonites operated on diverse materials. Two hibonite-bearing microspherules, Colony SP1 and ALH82101 SP15, exhibit nearly flat REE patterns with negative europium anomalies and slightly negative ? 26Mg. ALH82101 SP15 has resolved excesses of 48Ca and 50Ti. These characteristics are similar to those of previously described microspherules from Murchison and Lance, implying that the microspherules formed via a single process from related, but not identical source materials.

Russell, S. S.; Huss, G. R.; Fahey, A. J.; Greenwood, R. C.; Hutchison, R.; Wasserburg, G. J.

1998-02-01

57

Barium enema  

MedlinePLUS

Barium enema is a special x-ray of the large intestine, which includes the colon and rectum. ... to a bag that holds a liquid containing barium sulfate. This is a contrast material that highlights ...

58

Early life stage brook trout (Salvelinus fontinalis) experiment to determine the effects of pH, calcium and aluminum in low conductivity water  

SciTech Connect

Recruitment failure has been suggested as a mechanism leading to loss of fish populations in acidified streams and lakes. Numerous laboratory studies have investigated the effects of pH, aluminum, and calcium, alone or in combination, on early life stages of fish; however, the exposures in these experiments have been of relatively short duration. The objective of the present study was to determine the chronic effects of elevated aluminum concentrations as a function of pH and calcium level on hatching success and subsequent fry survival of brook trout. Brook trout eyed eggs (25 per chamber) were exposed to a replicated matrix of four levels each of pH and calcium and five levels of aluminum totaling 64 different combinations in a 40-day test. The levels of pH, aluminum, and calcium were chosen to represent the chemistry of sensitive lakes and streams in eastern Canada, the northeastern United States, and Scandinavia. We exposed fish to higher aluminum concentrations at lower pH levels, based on the observation that in acidified natural waters, dissolved inorganic aluminum increases as pH decreases (e.g., Shofield 1982). The results presented are based on nominal pH, aluminum, and calcium levels. 9 refs., 12 figs., 4 tabs.

Ingersoll, C.G.; La Point, T.W.; Bergman, H.L.; Breck, J.

1984-01-01

59

Acid precipitation and food quality: Inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium, and phosphorus  

Microsoft Academic Search

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain

Donald W. Sparling

1990-01-01

60

Use of calcium/aluminum ratios as indicators of stress in forest ecosystems  

SciTech Connect

The calcium/aluminum (Ca/Al) molar ratio of the soil solution provides a valuable measurement endpoint or ecological indicator for identification of approximate thresholds beyond which the risk of forest damage from Al stress and nutrient imbalances increases. The Ca/Al ratio can also be used as an indicator to assess forest ecosystem changes over time in response to acidic deposition, forest harvesting, or other processes contributing to acid soil infertility. Based on a critical review of literature on Al stress, we estimate that there is a 50:50 risk of adverse impacts on tree growth or nutrition when the soil solution Ca/Al ratio is as low as 1.0, a 75% risk when the soil solution ratio is as low as 0.5, and nearly a 100% risk when the soil solution Ca/Al molar ratio is as low as 0.2. The Ca/Al ratio of the soil solution can be corroborated with other complementary indices.

Cronan, C.S. [Univ. of Maine, Orono, ME (United States); Grigal, D.F. [Univ. of Minnesota, St. Paul, MN (United States)

1995-03-01

61

Effect of calcium and aluminum concentrations on the survival of brown trout (Salmo trutta) at low pH  

SciTech Connect

In this paper, the results of experiments to determine the survival times of yolk sac fry of brown trout (Salmo trutta) in a range of pHs, calcium and aluminium solutions are described, and the relevance of the results to the field situation is also discussed. In the absence of aluminum, mortalities occur at pH 4.5 only with 0.25 and 0.5 mg 1/sup -1/ of calcium. In solutions containing 0.25 mg 1/sup -1/ of aluminium, however, a complete range of responses is seen, from no or very low survival with 0.25 mg 1/sup -1/ of calcium to almost complete survival with 2.0 mg 1/sup -1/ of calcium. Solutions containing 0.5 mg 1/sup -1/ of aluminium lead to almost complete mortalities with calcium concentrations of 0.25 and 0.5 mg 1/sup -1/ and still significant mortalities at higher calcium concentrations. In general, the effect of pH throughout the range tested is not so marked, but there is a tendency for higher pHs to be more toxic especially in solutions containing 0.5 mg 1/sup -1/ of aluminium.

Brown, D.J.A.

1983-01-01

62

Disturbance of intracellular calcium homeostasis and CaMKII/CREB signaling is associated with learning and memory impairments induced by chronic aluminum exposure.  

PubMed

Aluminum-induced neuronal injury has been implicated in various neurodegenerative disorders. However, the underlying mechanism involved in this pathogenesis still remains unknown. Our present findings demonstrated that chronic aluminum exposure resulted in spatial learning impairment and significantly increased intracellular calcium level in the hippocampus of rats. Examination of the associated protein molecules essential for induction and maintenance of long-term potentiation revealed that aluminum exposure could increase the expression level of calmodulin (CaM), but the expression levels of CaM-dependent protein kinase II (CaMKII), and phosphorylated cAMP-responsive element binding protein (CREB) were significantly reduced, whereas the total protein levels of CaMKII and CREB did not change in the aluminum-treated hippocampus. Thus, we provide a previously unrecognized mechanism whereby chronic aluminum exposure impairs hippocampal learning and memory, at least in part, through disruption of intracellular calcium homeostasis and CaM/CaMKII/CREB signaling pathway. PMID:24366850

Wang, Biao; Zhao, Jiuhan; Yu, Meng; Meng, Xin; Cui, Xin; Zhao, Yan; Zhu, Yuyan; Xing, Wei; Guan, Yifu

2014-07-01

63

21 CFR 82.1051 - Lakes (D&C).  

Code of Federal Regulations, 2011 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or any combination of two...potassium, aluminum, barium, calcium, strontium, or zirconium...potassium, aluminum, barium, calcium, strontium, or zirconium....

2011-04-01

64

21 CFR 82.1051 - Lakes (D&C).  

Code of Federal Regulations, 2013 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or any combination of two...potassium, aluminum, barium, calcium, strontium, or zirconium...potassium, aluminum, barium, calcium, strontium, or zirconium....

2013-04-01

65

21 CFR 82.1051 - Lakes (D&C).  

Code of Federal Regulations, 2012 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or any combination of two...potassium, aluminum, barium, calcium, strontium, or zirconium...potassium, aluminum, barium, calcium, strontium, or zirconium....

2012-04-01

66

21 CFR 82.1051 - Lakes (D&C).  

Code of Federal Regulations, 2014 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or any combination of two...potassium, aluminum, barium, calcium, strontium, or zirconium...potassium, aluminum, barium, calcium, strontium, or zirconium....

2014-04-01

67

Calmodulin concentration in mucus of rainbow trout, Salmo gairdneri, exposed to combinations of acid, aluminum, and calcium  

SciTech Connect

As a result of increasing acidification in various watersheds elevated levels of aluminum have been observed in soil and surface water. The toxicity of Al to fish has been shown to be positively correlated with the concentration of inorganic monomeric. The exact mechanism(s) of Al toxicity is not fully understood. Recently, the presence of calmodulin (CaM), a calcium-regulating protein, has been reported in fish gills and mucus. Calmodulin selectively binds inorganic monomeric Al causing conformational changes in the protein. Aluminum-induced conformational changes cause a reduction in the ability of calmodulin to mediate Ca-dependent phosphodiesterase and ATPase activity. Calmodulin also plays a key role in coordinating the effects of secondary messenger systems in response to cellular stimulation. Given the involvement of calmodulin in numerous biochemical pathways, its interaction with aluminum may be a key lesion in the broadly defined syndrome of aluminum toxicity. The present study was undertaken to establish a relationship between Al concentration in aqueous solution and the quantity and activity of CaM in the mucus of adult rainbow trout (Salmo gairdneri). Fish were exposed to various levels of pH, Ca, and Al. Mucus was collected and the amount of CaM was determined. The ability of the Al-exposed CaM to activate the phosphodiesterase enzyme system was also evaluated.

Lewis, T.E. (Lockheed Engineering and Sciences Company, Las Vegas, NV (USA)); Yuan, Shixing; Haug, A. (Michigan State Univ., East Lansing (USA))

1990-03-01

68

Calcium  

MedlinePLUS

... following: Milk, yogurt, and cheese are the main food sources of calcium for the majority of people in ... on Calcium Minerals, MedlinePlus® For more information on food sources of calcium: U.S. Department of Agriculture's (USDA) National ...

69

Comparison of the adjuvant activity of aluminum hydroxide and calcium phosphate on the antibody response towards Bothrops asper snake venom.  

PubMed

The adjuvanticity of aluminum hydroxide and calcium phosphate on the antibody response in mice towards the venom of the snake Bothrops asper was studied. It was found that, in vitro, most of the venom proteins are similarly adsorbed by both mineral salts, with the exception of some basic phospholipases A2, which are better adsorbed by calcium phosphate. After injection, the adjuvants promoted a slow release of the venom, as judged by the lack of acute toxicity when lethal doses of venom were administered to mice. Leukocyte recruitment induced by the venom was enhanced when it was adsorbed on both mineral salts; however, venom adsorbed on calcium phosphate induced a higher antibody response towards all tested HPLC fractions of the venom. On the other hand, co-precipitation of venom with calcium phosphate was the best strategy for increasing: (1) the capacity of the salt to couple venom proteins in vitro; (2) the venom ability to induce leukocyte recruitment; (3) phagocytosis by macrophages; and (4) a host antibody response. These findings suggest that the chemical nature is not the only one determining factor of the adjuvant activity of mineral salts. PMID:23506358

Olmedo, Hidekel; Herrera, María; Rojas, Leonardo; Villalta, Mauren; Vargas, Mariángela; Leiguez, Elbio; Teixeira, Catarina; Estrada, Ricardo; Gutiérrez, José María; León, Guillermo; Montero, Mavis L

2014-01-01

70

Geochemical reactions and dynamics during titration of a contaminated groundwater with high uranium, aluminum, and calcium  

NASA Astrophysics Data System (ADS)

This study investigated possible geochemical reactions during titration of a contaminated groundwater with a low pH but high concentrations of aluminum, calcium, magnesium, manganese, and trace contaminant metals/radionuclides such as uranium, technetium, nickel, and cobalt. Both Na-carbonate and hydroxide were used as titrants, and a geochemical equilibrium reaction path model was employed to predict aqueous species and mineral precipitation during titration. Although the model appeared to be adequate to describe the concentration profiles of some metal cations, solution pH, and mineral precipitates, it failed to describe the concentrations of U during titration and its precipitation. Most U (as uranyl, UO 22+) as well as Tc (as pertechnetate, TcO 4-) were found to be sorbed and coprecipitated with amorphous Al and Fe oxyhydroxides at pH below ˜5.5, but slow desorption or dissolution of U and Tc occurred at higher pH values when Na 2CO 3 was used as the titrant. In general, the precipitation of major cationic species followed the order of Fe(OH) 3 and/or FeCo 0.1(OH) 3.2, Al 4(OH) 10SO 4, MnCO 3, CaCO 3, conversion of Al 4(OH) 10SO 4 to Al(OH) 3,am, Mn(OH) 2, Mg(OH) 2, MgCO 3, and Ca(OH) 2. The formation of mixed or double hydroxide phases of Ni and Co with Al and Fe oxyhydroxides was thought to be responsible for the removal of Ni and Co in solution. Results of this study indicate that, although the hydrolysis and precipitation of a single cation are known, complex reactions such as sorption/desorption, coprecipitation of mixed mineral phases, and their dissolution could occur simultaneously. These processes as well as the kinetic constraints must be considered in the design of the remediation strategies and modeling to better predict the activities of various metal species and solid precipitates during pre- and post-groundwater treatment practices.

Gu, Baohua; Brooks, Scott C.; Roh, Yul; Jardine, Philip M.

2003-08-01

71

Calcium-aluminum-silicate-hydrate "cement" phases and rare Ca-zeolite association at Colle Fabbri, Central Italy  

NASA Astrophysics Data System (ADS)

Very high temperature, Ca-rich alkaline magma intruded an argillite formation at Colle Fabbri, Central Italy, producing cordierite-tridymite metamorphism in the country rocks. An intense Ba-rich sulphate-carbonate-alkaline hydrothermal plume produced a zone of mineralization several meters thick around the igneous body. Reaction of hydrothermal fluids with country rocks formed calcium-silicate-hydrate (CSH), i.e., tobermorite-afwillite-jennite; calcium-aluminum-silicate-hydrate (CASH) — "cement" phases - i.e., thaumasite, strätlingite and an ettringite-like phase and several different species of zeolites: chabazite-Ca, willhendersonite, gismon-dine, three phases bearing Ca with the same or perhaps lower symmetry of phillipsite-Ca, levyne-Ca and the Ca-rich analogue of merlinoite. In addition, apophyllite-(KF) and/or apophyllite-(KOH), Ca-Ba-carbonates, portlandite and sulphates were present. A new polymorph from the pyrrhotite group, containing three layers of sphalerite-type structure in the unit cell, is reported for the first time. Such a complex association is unique. Most of these minerals are specifically related to hydration processes of: (1) pyrometamorphic metacarbonate/metapelitic rocks (natural analogues of cement clinkers); (2) mineralization between intrusive stocks and slates; and (3) high-calcium, alkaline igneous rocks such as melilitites and foidites as well as carbonatites. The Colle Fabbri outcrop offers an opportunity to study in situ complex crystalline overgrowth and specific crystal chemistry in mineral phases formed in igneous to hydrothermal conditions.

Stoppa, F.; Scordari, F.; Mesto, E.; Sharygin, V.; Bortolozzi, G.

2010-06-01

72

Calcium  

MedlinePLUS

... loss. Some clinical research shows that increasing calcium consumption from dairy products such as yogurt seems to ... and vitamin D. For weight loss, increasing calcium consumption from dairy products to total intake of 500- ...

73

Calcium  

MedlinePLUS

... strong bones and teeth. Why Do I Need Calcium? Bones grow rapidly during adolescence, and teens need ... salmon with bones. Almond milk. Back Continue Working Calcium Into Your Diet Looking for ways to up ...

74

Calcium  

MedlinePLUS

... and blood vessels contract and expand, to secrete hormones and enzymes and to send messages through the nervous system. It is important to get plenty of calcium in the foods you eat. Foods rich in calcium include Dairy ...

75

Physiological and toxicological effects of long-term exposure to acid, aluminum, and low calcium on adult brook trout (Salvelinus fontinalis) and rainbow trout (Salmo gairdneri)  

SciTech Connect

Although the toxic effects of these three parameters were highly interactive, survival and growth of adult brook trout were reduced at elevated aluminum concentrations. Only 40 ug/L aluminum was necessary to produce similar responses in rainbow trout. Neither species was sensitive to pH alone in the range 4.5-6.5 except at very low calcium concentrations. Reductions in fecundity were observed, but only as a result of decreased growth. Progeny spawned from brook trout that had been exposed to 0.5 mg/L calcium were more sensitive to continued exposure to acid, aluminum and low calcium than were progeny of control fish. Physiologically, brook and rainbow trout responded similarly to sublethal acid, aluminum and low calcium stress. All fish exposed to depressed pH showed reductions in plasma sodium, but in most cases they were able to maintain normal plasma osmolality. But those fish stressed most severely displayed an entire suite of disturbances, including decreased survival, growth and feeding, as well as abnormal vitellogenesis and ionoregulatory failure.

Mount, D.R.

1987-01-01

76

SOURCE ASSESSMENT: MAJOR BARIUM CHEMICALS  

EPA Science Inventory

This report summarizes data on air emissions from the production of major barium chemicals. Compounds studied include barium sulfide, barium carbonate, barium chloride, barium hydroxide, and barium sulfate. In order to evaluate potential environmental effects the source severity,...

77

Segregation and evaporation behaviors of aluminum and calcium in silicon during solidification process induced by electron beam  

NASA Astrophysics Data System (ADS)

An experimental investigation into the removal of aluminum (Al) and calcium (Ca) from molten silicon by using electron beam melting was carried out. Based on the distributions of Al and Ca along the growth direction of the ingot under different solidification conditions, the influence of segregation and evaporation behaviors on the removal of such impurities with both high saturated vapor pressure and low segregation coefficients was investigated. The results showed that the distributions of impurities depend upon the interaction between segregation and evaporation, so that the removal efficiency can be further improved by adjusting the melting parameters. Compared with the traditional electron beam melting process, the energy consumption decreases by 20% during the whole melting and solidification process. It is considered to be a more effective way for the purification of silicon and the reduction of energy consumption by electron beam melting.

Jiang, Dachuan; Shi, Shuang; Tan, Yi; Asghar, H. M. Noor ul Huda Khan; Qin, Shiqiang

2015-03-01

78

Growth of calcium-aluminum-rich inclusions by coagulation and fragmentation in a turbulent protoplanetary disk: observations and modelisation  

E-print Network

Whereas it is generally accepted that calcium-aluminum-rich inclusions (CAIs) from chondritic meteorites formed in a hot environment in the solar protoplanetary disk, the conditions of their formation remain debated. Recent laboratory studies of CAIs have provided new kind of data: their size distributions. We show that size distributions of CAIs measured in laboratory from sections of carbonaceous chondrites have a power law size distribution with cumulative size exponent between -1.7 and -1.9, which translates into cumulative size exponent between -2.5 and -2.8 after correction for sectioning. To explain these observations, numerical simulations were run to explore the growth of CAIs from micrometer to centimeter sizes, in a hot and turbulent protoplanetary disk through the competition of coagulation and fragmentation. We show that the size distributions obtained in growth simulations are in agreement with CAIs size distributions in meteorites. We explain the CAI sharp cut-off of their size distribution at ...

Charnoz, S; Chaumard, N; Baillie, K; Tallifet, E

2015-01-01

79

VS-501: a novel, nonabsorbed, calcium- and aluminum-free, highly effective phosphate binder derived from natural plant polymer  

PubMed Central

Inadequate control of serum phosphate in chronic kidney disease can lead to pathologies of clinical importance. Effectiveness of on-market phosphate binders is limited by safety concerns and low compliance due to high pill size/burden and gastrointestinal (GI) discomfort. VS-501 is a nonabsorbed, calcium- and aluminum-free, chemically modified, plant-derived polymer. In vitro studies show that VS-501 has a high density and a low swell volume when exposed to simulated gastric fluid (vs. sevelamer). When male Sprague–Dawley (SD) rats on normal diet were treated with VS-501 or sevelamer, serum phosphate was not significantly altered, but urinary phosphate levels decreased by >90%. VS-501 had no effect on serum calcium (Ca) or urinary Ca, while 3% sevelamer significantly increased serum and urine Ca. In 5/6 nephrectomized (NX) uremic SD rats on high-phosphate diet, increasing dietary phosphate led to an increase in serum and urine phosphate, which was prevented in rats treated with VS-501 or sevelamer (0.2–5% in food). High-phosphate diet also increased serum fibroblast growth factor-23 and parathyroid hormone in 5/6 NX rats that was prevented by VS-501 or sevelamer. VS-501 or sevelamer increased fecal phosphate in a dose-dependent manner. More aortic calcification was observed in 5/6 NX rats treated with 5% sevelamer, while VS-501 and sevelamer did not show significant effects on cardiac parameters, fibrosis, intestine histology, and intestinal sodium-dependent phosphate cotransporter gene expression. These results suggest that VS-501 is effective in binding phosphate with no effects on calcium homeostasis, and may have improved pill burden and GI side effects. PMID:25197556

Wu-Wong, J Ruth; Chen, Yung-wu; Gaffin, Robert; Hall, Andy; Wong, Jonathan T; Xiong, Joseph; Wessale, Jerry L

2014-01-01

80

Electrical and chemical analysis of zinc oxide interfaces with high dielectric constant barium tantalate and aluminum oxide in metal-insulator-semiconductor structures fabricated at Low temperatures  

Microsoft Academic Search

Zinc oxide (ZnO) was incorporated into metal-insulator-semiconductor (MIS) structures featuring high dielectric constant (high-?) barium tantalate (BaTa2O6)or alumina (Al2O3)as the insulator, and the structures were electrically evaluated for potential applications in transparent thin film transistors. The ZnO films were deposited by radio-frequency magnetron sputtering at 100°C whereas the dielectric films were deposited by the same method at room temperature. The

Fang-Ling Kuo; Mohammad H. Maneshian; Nigel D. Shepherd

2011-01-01

81

Efficiency and purity control in the preparation of pure and\\/or aluminum-doped barium ferrites by hydrothermal methods using ferrous ions as reactants  

Microsoft Academic Search

The synthesis of hexagonal barium ferrite (BaFe12O19) was studied under hydrothermal conditions by a method in which a significant amount of ferrous chloride was introduced alongside ferric chloride among the starting materials. Though all of the Fe2+ ions in the starting material were converted to Fe3+ ions in the final product, Fe2+ was confirmed to participate differently from the Fe3+

Ying Liu; Michael G. B. Drew; Jingping Wang; Milin Zhang; Yue Liu

2010-01-01

82

Investigation of the interface formation between calcium and tris-(8-hydroxy quinoline) aluminum  

NASA Astrophysics Data System (ADS)

X-ray and ultraviolet photoemission spectroscopy investigations reveal strong interactions between Ca and tris-(8-hydroxy quinoline) aluminum (Alq3) during the Ca/Alq3 interface formation. The details of the interaction depend on the direction of the interface formation. For the case of Ca deposited on Alq3, a staged interface reaction is observed. For low Ca coverages (?Ca?4 Å), negatively charged Alq3 radical anions are formed by electron transfer from the Ca. The emergence of new states in the energy gap is observed in the UPS spectra. At higher coverages, the Ca reacts with the phenoxide oxygen resulting in the decomposition of the Alq3 molecule. On the other hand, for the case of Alq3 deposited on Ca, a strong chemical reaction takes place as soon as Alq3 is deposited, and Ca attacks every constituent of Alq3. Finally, no interaction occurs between Alq3 and the Ca substrate if the substrate has been passivated by oxygen prior to the Alq3 deposition.

Choong, V.-E.; Mason, M. G.; Tang, C. W.; Gao, Yongli

1998-05-01

83

Growth of calcium-aluminum-rich inclusions by coagulation and fragmentation in a turbulent protoplanetary disk: Observations and simulations  

NASA Astrophysics Data System (ADS)

Whereas it is generally accepted that calcium-aluminum-rich inclusions (CAIs) from chondritic meteorites formed in a hot environment in the solar protoplanetary disk, the conditions of their formation remain debated. Recent laboratory studies of CAIs have provided new kind of data: their size distributions. We report that size distributions of CAIs measured in laboratory from sections of carbonaceous chondrites have a power law size distribution with cumulative size exponent between -1.7 and -1.9, which translates into cumulative size exponent between -2.5 and -2.8 after correction for sectioning. To explain these observations, numerical simulations were run to explore the growth of CAIs from micrometer to centimeter sizes, in a hot and turbulent protoplanetary disk through the competition of coagulation and fragmentation. We show that the size distributions obtained in growth simulations are in agreement with CAIs size distributions in meteorites. We explain the CAI sharp cut-off of their size distribution at centimeter sizes as the direct result from the famous fragmentation barrier, provided that CAI fragment for impact velocities larger than 10 m/s. The growth/destruction timescales of millimeter- and centimeter-sized CAIs is inversely proportional to the local dust/gas ratio and is about 10 years at 1300 K and up to 104 years at 1670 K. This implies that the most refractory CAIs are expected to be smaller in size owing to their long growth timescale compared to less refractory CAIs. Conversely, the least refractory CAIs could have been recycled many times during the CAI production era which may have profound consequences for their radiometric age.

Charnoz, Sébastien; Aléon, Jérôme; Chaumard, Noël; Baillié, Kévin; Taillifet, Esther

2015-05-01

84

Oxygen isotope heterogeneities in the earliest protosolar gas recorded in a meteoritic calcium aluminum-rich inclusion  

NASA Astrophysics Data System (ADS)

Combined petrologic, oxygen and magnesium isotopic and trace element analyses of a compound calcium-aluminum-rich inclusion (CAI) from the Efremovka reduced CV3 carbonaceous chondrite reveal that it consists of a Mg-rich, 16O-rich xenolithic CAI, previously altered in the nebula, that impacted an extensively molten, 16O-depleted, type A host CAI shortly before the end of the host's crystallization. Convoluted regions in the xenolith were probably formed by rapid crystallization of the partial melt produced during impact. Oxygen isotopic ratios in the host CAI are correlated both with melilite chemistry and location in the inclusion. The region immediately inside the Wark-Lovering rim of the CAI consists of 16O-rich gehlenite with ? 17O ranging down to - 20‰ but melilite becomes progressively 16O-poor (? 17O ˜ 0‰) and Mg-rich towards the interior. In the absence of Mg isotopic fractionation, this variation is best attributed to O isotopic exchange between the nebular gas and the partially molten inclusion during its crystallization. This event lasted less than 200 h, which implies that the host CAI was transported between two nebular reservoirs with distinct O isotopic compositions during this time. Examination of possible transport mechanisms suggests that the transport occurred over a distance of less than 1 astronomical unit. The close-to-canonical 26Al/ 27Al ratio of 4.1 × 10 - 5 determined from both inclusions implies that at most 670,000 yr after the birth of the Solar System, the 16O-rich reservoir was spatially limited and an 16O-poor reservoir with typical planetary isotopic composition was available for planet formation.

Aléon, Jérôme; El Goresy, Ahmed; Zinner, Ernst

2007-11-01

85

Emission spectrographic determination of barium in sea water using a cation exchange concentration procedure  

USGS Publications Warehouse

A concentration technique employing Dowex 50W cation exchange resin is described for the determination of barium in sea water. The separated barium is precipitated as fluoride together with calcium and strontium and measured by emission spectrographic analysis. The vertical distribution of barium in sea water has been measured in the Caribbean Sea and the Atlantic Ocean. The barium content varied between 7 and 23 ??g. per liter; in two profiles, the lowest concentrations were at a depth of about 1000 meters.

Szabo, B. J.; Joensuu, O.

1967-01-01

86

Barium and molybdenum records in bivalve shells: Geochemical proxies for phytoplankton dynamics in coastal environments?  

E-print Network

Abstract Barium : calcium and molybdenum : calcium ratios were investigated in shells of the tropicalBarium and molybdenum records in bivalve shells: Geochemical proxies for phytoplankton dynamics coupled plasma mass spectrometer. Absolute dates of shell precipitation assigned on the basis of periodic

87

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.  

Code of Federal Regulations, 2014 CFR

...cobalt carbonate, and aluminum oxide. It may contain small amounts (less than 1 percent each) of oxides of barium, boron, silicon, and nickel. (b) Specifications. Chromium-cobalt-aluminum oxide shall conform to the following...

2014-04-01

88

Constraints on formation processes of two coarse-grained calcium- aluminum-rich inclusions: a study of mantles, islands and cores  

USGS Publications Warehouse

Many coarse-grained calcium- aluminum-rich inclusions (CAIs) contain features that are inconsistent with equilibrium liquid crystallization models of origin. Spinel-free islands (SFIs) in spinel-rich cores of Type B CAIs are examples of such features. One model previously proposed for the origin of Allende 5241, a Type B1 CAI containing SFIs, involves the capture and assimilation of xenoliths by a liquid droplet in the solar nebula (El Goresy et al, 1985; MacPherson et al 1989). This study reports new textural and chemical zoning data from 5241 and identifies previously unrecognized chemical zoning patterns in the melilite mantle and in a SFI. -from Author

Meeker, G.P.

1995-01-01

89

Final report on the safety assessment of aluminum silicate, calcium silicate, magnesium aluminum silicate, magnesium silicate, magnesium trisilicate, sodium magnesium silicate, zirconium silicate, attapulgite, bentonite, Fuller's earth, hectorite, kaolin, lithium magnesium silicate, lithium magnesium sodium silicate, montmorillonite, pyrophyllite, and zeolite.  

PubMed

This report reviews the safety of Aluminum, Calcium, Lithium Magnesium, Lithium Magnesium Sodium, Magnesium Aluminum, Magnesium, Sodium Magnesium, and Zirconium Silicates, Magnesium Trisilicate, Attapulgite, Bentonite, Fuller's Earth, Hectorite, Kaolin, Montmorillonite, Pyrophyllite, and Zeolite as used in cosmetic formulations. The common aspect of all these claylike ingredients is that they contain silicon, oxygen, and one or more metals. Many silicates occur naturally and are mined; yet others are produced synthetically. Typical cosmetic uses of silicates include abrasive, opacifying agent, viscosity-increasing agent, anticaking agent, emulsion stabilizer, binder, and suspending agent. Clay silicates (silicates containing water in their structure) primarily function as adsorbents, opacifiers, and viscosity-increasing agents. Pyrophyllite is also used as a colorant. The International Agency for Research on Cancer has ruled Attapulgite fibers >5 microm as possibly carcinogenic to humans, but fibers <5 microm were not classified as to their carcinogenicity to humans. Likewise, Clinoptilolite, Phillipsite, Mordenite, Nonfibrous Japanese Zeolite, and synthetic Zeolites were not classified as to their carcinogenicity to humans. These ingredients are not significantly toxic in oral acute or short-term oral or parenteral toxicity studies in animals. Inhalation toxicity, however, is readily demonstrated in animals. Particle size, fibrogenicity, concentration, and mineral composition had the greatest effect on toxicity. Larger particle size and longer and wider fibers cause more adverse effects. Magnesium Aluminum Silicate was a weak primary skin irritant in rabbits and had no cumulative skin irritation in guinea pigs. No gross effects were reported in any of these studies. Sodium Magnesium Silicate had no primary skin irritation in rabbits and had no cumulative skin irritation in guinea pigs. Hectorite was nonirritating to the skin of rabbits in a Draize primary skin irritation study. Magnesium Aluminum Silicate and Sodium Magnesium Silicate caused minimal eye irritation in a Draize eye irritation test. Bentonite caused severe iritis after injection into the anterior chamber of the eyes of rabbits and when injected intralamellarly, widespread corneal infiltrates and retrocorneal membranes were recorded. In a primary eye irritation study in rabbits, Hectorite was moderately irritating without washing and practically nonirritating to the eye with a washout. Rats tolerated a single dose of Zeolite A without any adverse reaction in the eye. Calcium Silicate had no discernible effect on nidation or on maternal or fetal survival in rabbits. Magnesium Aluminum Silicate had neither a teratogenic nor adverse effects on the mouse fetus. Female rats receiving a 20% Kaolin diet exhibited maternal anemia but no significant reduction in birth weight of the pups was recorded. Type A Zeolite produced no adverse effects on the dam, embryo, or fetus in either rats or rabbits at any dose level. Clinoptilolite had no effect on female rat reproductive performance. These ingredients were not genotoxic in the Ames bacterial test system. In primary hepatocyte cultures, the addition of Attapulgite had no significant unscheduled DNA synthesis. Attapulgite did cause significant increases in unscheduled DNA synthesis in rat pleural mesothelial cells, but no significant increase in sister chromosome exchanges were seen. Zeolite particles (<10 microm) produced statistically significant increase in the percentage of aberrant metaphases in human peripheral blood lymphocytes and cells collected by peritoneal lavage from exposed mice. Topical application of Magnesium Aluminum Silicate to human skin daily for 1 week produced no adverse effects. Occupational exposure to mineral dusts has been studied extensively. Fibrosis and pneumoconiosis have been documented in workers involved in the mining and processing of Aluminum Silicate, Calcium Silicate, Zirconium Silicate, Fuller's Earth, Kaolin, Montmorillonite, Pyrophyllite, and Zeolite. The Cosmetic Ingre

Elmore, Amy R

2003-01-01

90

Barium enema (image)  

MedlinePLUS

A barium enema is performed to examine the walls of the colon. During the procedure, a well lubricated enema tube is inserted gently into the rectum. The barium, a radiopaque (shows up on X-ray) contrast ...

91

Metabolic responses of postmenopausal women to supplemental dietary boron and aluminum during usual and low magnesium intake: boron, calcium, and magnesium absorption and retention and blood mineral concentrations.  

PubMed

Findings from animal studies indicate that dietary boron affects several aspects of mineral metabolism, especially when animals are subjected to nutritional stressors. Eleven postmenopausal volunteers living on a metabolic ward for 167 d (one 23-d equilibration period and six 24-d treatment periods) were fed a conventional basal diet that supplied a daily average intake of 0.36 mg B, 109 mg Mg, and < 0.10 mg A1/8400 kJ. They were given supplements of 0 (BB) or 3 mg B (SB, last two periods only), 0 (BMg) or 200 mg Mg (SMg) (with magnesium supplements held constant during the last two periods), or 0 (BAl) or 1000 mg A1 (SAl)/d. The SB treatment, compared with the BB treatment, provided a 9.0-fold increase in dietary boron but yielded only a 1.5-fold increase in plasma boron concentrations. Regardless of boron dietary treatment, fecal plus urinary excretion of boron accounted for nearly 100% of dietary boron intake with no evidence of boron accumulation over time. Lack of boron accumulation and relatively small changes in blood boron values during a substantial increase in dietary boron support the concept of boron homeostasis. In subjects fed BMg, SB decreased the percentage of dietary calcium lost in the urine but increased that percentage in volunteers fed SMg, a relation that may be important in understanding metabolic mineral disorders that perturb calcium balance. Reduced calcium absorption during SAl suggests that aluminum supplementation should be limited or at least monitored in postmenopausal women prone to excessive calcium loss. Decreased total urinary oxalate during SB in BMg subjects indicates a possible role for boron in the control of urolithiasis during low-magnesium nutriture. PMID:9062533

Hunt, C D; Herbel, J L; Nielsen, F H

1997-03-01

92

Barium titanium glycolate: A new barium titanate powder precursor  

SciTech Connect

This paper describes the synthesis and structure of a barium titanium glycolate complex and the calcination into barium titanate preceramic powders that sinter into polycrystalline, tetragonal barium titanate having good dielectric properties.

Day, V.W.; Klemperer, W.G.; Payne, D.A. [Univ. of Nebraska, Lincoln, NE (United States)] [and others] [Univ. of Nebraska, Lincoln, NE (United States); and others

1996-02-01

93

Barium ferrite permanent magnets  

Microsoft Academic Search

1.We have selected and introduced the following optimum conditions for the preparation of isotropic barium ferrite magnets:a)Barium oxide content 15 ± 1%; b) kaolin content 1%; c) roasting of mixture of ferric oxide and barium salt at temperatures of 900–950‡ with five hours holding time; d) pressure during pressing 1.5–2 t\\/cm2; e) sintering of magnets at a temperature of 1160–1260‡

I. Yu. Gershov

1964-01-01

94

Acid precipitation and food quality: inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium, and phosphorus.  

PubMed

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain and its effects may be one of the factors negatively impacting American black ducks (Anas rubripes) in eastern North America. One-day old mallards (A. platyrhynchos) and black ducks were placed on one of three Ca:P regimens: low:low (LL), normal:normal (NN), and low:high (LH) with each regimen divided further into three or four Al levels for 10 weeks. Forty-five % of the black ducks died on nine different diets whereas only 28% of the mallards died on three different diets. Mortality was significantly related to diet in both species. Growth rates for body weight, culmens, wings, and tarsi of both species on control diets exceeded those on many treatment diets but the differences were less apparent for mallards than for black ducks. Differences among treatments were due to both Ca:P and Al levels. PMID:2353844

Sparling, D W

1990-01-01

95

Acid precipitation and food quality: Inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium and phosphorus  

USGS Publications Warehouse

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain and its effects may be one of the factors negatively impacting American black ducks (Anas rubripes) in eastern North America. One-day old mallards (A. platyrhynchos) and black ducks were placed on one of three Ca:P regimens: low:low (LL), normal:normal (NN), and low:high (LH) with each regimen divided further into three or four Al levels for 10 weeks. Forty-five % of the black ducks died on nine different diets whereas only 28% of the mallards died on three different diets. Mortality was significantly related to diet in both species. Growth rates for body weight, culmens, wings, and tarsi of both species on control diets exceeded those on many treatment diets but the differences were less apparent for mallards than for black ducks. Differences among treatments were due to both Ca:P and Al levels.

Robbins, C.S.

1990-01-01

96

Molecular Structure of Barium Chloride  

NSDL National Science Digital Library

Barium Chloride was the byproduct of the discovery of radium by Madame Curie. When refining radium, the final separation resulted in barium chloride and radium chloride. Electrophoresis of barium chloride produces small-scale amounts of barium atom. This can be used for obtaining barium for commercial uses. Applications of barium chloride include stimulating the heart and other muscles for medicinal purposes, and also for softening water. Other uses of barium chloride include the manufacturing of barium salts, as pesticide, pigments, boiler detergent, in purifying sugar, as mordant in dyeing and printing textiles, and in the manufacture of caustic soda, polymers, and stabilizers.

2002-08-15

97

Effect of calcium and aluminum concentrations on the survival of brown trout ( Salmo trutta ) at low pH  

Microsoft Academic Search

Experimental evidence suggests that the two most important ions with respect to survival of fish at low pHs are calcium (BROWN 1981, 1982a and b; BROWN and LYNAM 1981) and aluminium (SCHOFIELD and TROJNAR 1980; BAKER and SCHOFIELD 1980, 1982). A minimal concentration of the former ion is necessary for survival, and in general, elevated concentrations of aluminium reduce survival.

D. J. A. Brown

1983-01-01

98

Barium Abundances in Cepheids  

E-print Network

We derived the barium atmospheric abundances for a large sample of Cepheids, comprising 270 stars. The sample covers a large range of galactocentric distances, from about 4 to 15 kpc, so that it is appropriated to investigate the existence of radial barium abundance gradients in the galactic disc. In fact, this is the first time that such a comprehensive analysis of the distribution of barium abundances in the galactic disc is carried out. As a result, we conclude that the Ba abundance distribution can be characterized by a zero gradient. This result is compared with derived gradients for other elements, and some reasons are briefly discussed for the independence of the barium abundances upon galactocentric distances.

Andrievsky, S M; Korotin, S A; Luck, R E; Kovtyukh, V V; Maciel, W J

2012-01-01

99

Refinement of the crystal structure of calcium-lithium-aluminum tourmaline from the pegmatite vein in the Sangilen Upland (Tuva Republic)  

SciTech Connect

The crystal structure of a natural calcium-lithium-aluminum tourmaline, which has the unique composition (Ca{sub 0.62}Na{sub 0.32}{open_square}{sub 0.06})(Al{sub 1.08}Li{sub 0.99}Fe{sub 0.66}{sup 2+} Mg{sub 0.24}Ti{sub 0.03})Al{sub 6}[Si{sub 6}O{sub 18}](BO{sub 3}){sub 3}(OH{sub 2.28}O{sub 0.72}) {center_dot} (F{sub 0.84}O{sub 0.16}), is refined (R = 0.019, R{sub w} = 0.022, S = 1.47). It is found that the O(1)(W) site is split into two sites, O(1) and O(11), which are incompletely occupied by fluorine and oxygen anions, respectively, and that the O(3)(V) site contains bivalent oxygen anions. The solid solution studied is close in composition to the liddicoatite mineral species and differs from the latter one by the Li: Al ratio in the Y octahedra and the presence of bivalent oxygen anions in the O(3) site. The tourmaline studied differs from the hypothetical oxyliddicoatite by the population of the O(1)(W) site by fluorine and accommodation of additional oxygen anions in the O(3)(V) site.

Rozhdestvenskaya, I. V., E-mail: ivrozhdestvenska@mail.ru; Bronzova, Yu. M.; Frank-Kamenetskaya, O. V.; Zolotarev, A. A. [St. Petersburg State University, Department of Crystallography (Russian Federation); Kuznetsova, L. G. [Russian Academy of Sciences, Vinogradov Institute of Geochemistry, Siberian Branch (Russian Federation); Bannova, I. I. [St. Petersburg State University, Department of Crystallography (Russian Federation)

2008-03-15

100

Refinement of the crystal structure of calcium-lithium-aluminum tourmaline from the pegmatite vein in the Sangilen Upland (Tuva Republic)  

SciTech Connect

The crystal structure of a natural calcium-lithium-aluminum tourmaline, which has the unique composition (Ca{sub 0.62}Na{sub 0.32}{open_square}{sub 0.06})(Al{sub 1.08}Li{sub 0.99}Fe{sub 0.66}{sup 2+} Mg{sub 0.24}Ti{sub 0.03})Al{sub 6}[Si{sub 6}O{sub 18}](BO{sub 3}){sub 3}(OH{sub 2.28}O{sub 0.72}) . (F{sub 0.84}O{sub 0.16}), is refined (R = 0.019, R{sub w} = 0.022, S = 1.47). It is found that the O(1)(W) site is split into two sites, O(1) and O(11), which are incompletely occupied by fluorine and oxygen anions, respectively, and that the O(3)(V) site contains bivalent oxygen anions. The solid solution studied is close in composition to the liddicoatite mineral species and differs from the latter one by the Li: Al ratio in the Y octahedra and the presence of bivalent oxygen anions in the O(3) site. The tourmaline studied differs from the hypothetical oxyliddicoatite by the population of the O(1)(W) site by fluorine and accommodation of additional oxygen anions in the O(3)(V) site.

Rozhdestvenskaya, I. V., E-mail: ivrozhdestvenska@mail.ru; Bronzova, Yu. M.; Frank-Kamenetskaya, O. V.; Zolotarev, A. A. [St. Petersburg State University, Department of Crystallography (Russian Federation); Kuznetsova, L. G. [Russian Academy of Sciences, Vinogradov Institute of Geochemistry, Siberian Branch (Russian Federation); Bannova, I. I. [St. Petersburg State University, Department of Crystallography (Russian Federation)

2008-03-15

101

AN ALUMINUM/CALCIUM-RICH, IRON-POOR, WHITE DWARF STAR: EVIDENCE FOR AN EXTRASOLAR PLANETARY LITHOSPHERE?  

SciTech Connect

The presence of elements heavier than helium in white dwarf atmospheres is often a signpost for the existence of rocky objects that currently or previously orbited these stars. We have measured the abundances of various elements in the hydrogen-atmosphere white dwarfs G149-28 and NLTT 43806. In comparison with other white dwarfs with atmospheres polluted by heavy elements, NLTT 43806 is substantially enriched in aluminum but relatively poor in iron. We compare the relative abundances of Al and eight other heavy elements seen in NLTT 43806 with the elemental composition of bulk Earth, with simulated extrasolar rocky planets, with solar system meteorites, with the atmospheric compositions of other polluted white dwarfs, and with the outer layers of the Moon and Earth. The best agreement is found with a model that involves accretion of a mixture of terrestrial crust and upper mantle material onto NLTT 43806. The implication is that NLTT 43806 is orbited by a differentiated rocky planet, perhaps quite similar to Earth, that has suffered a collision that stripped away some of its outer layers.

Zuckerman, B.; Klein, B.; Jura, M. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Koester, D. [Institut fur Theoretische Physik und Astrophysik, University of Kiel, 24098 Kiel (Germany); Dufour, P. [Departement de Physique, Universite de Montreal, Montreal, QC H3C 3J7 (Canada); Melis, Carl [Center for Astrophysics and Space Sciences, University of California, San Diego, CA 92093-0424 (United States)

2011-10-01

102

Factors controlling soil water and stream water aluminum concentrations after a clearcut in a forested watershed with calcium-poor soils  

USGS Publications Warehouse

The 24 ha Dry Creek watershed in the Catskill Mountains of southeastern New York State USA was clearcut during the winter of 1996-1997. The interactions among acidity, nitrate (NO3- ), aluminum (Al), and calcium (Ca2+) in streamwater, soil water, and groundwater were evaluated to determine how they affected the speciation, solubility, and concentrations of Al after the harvest. Watershed soils were characterized by low base saturation, high exchangeable Al concentrations, and low exchangeable base cation concentrations prior to the harvest. Mean streamwater NO3- concentration was about 20 ??mol l-1 for the 3 years before the harvest, increased sharply after the harvest, and peaked at 1,309 ??mol l -1 about 5 months after the harvest. Nitrate and inorganic monomeric aluminum (Alim) export increased by 4-fold during the first year after the harvest. Alim mobilization is of concern because it is toxic to some fish species and can inhibit the uptake of Ca2+ by tree roots. Organic complexation appeared to control Al solubility in the O horizon while ion exchange and possibly equilibrium with imogolite appeared to control Al solubility in the B horizon. Alim and NO3- concentrations were strongly correlated in B-horizon soil water after the clearcut (r2 = 0.96), especially at NO3- concentrations greater than 100 ??mol l-1. Groundwater entering the stream from perennial springs contained high concentrations of base cations and low concentrations of NO3- which mixed with acidic, high Alim soil water and decreased the concentration of Alim in streamwater after the harvest. Five years after the harvest soil water NO 3- concentrations had dropped below preharvest levels as the demand for nitrogen by regenerating vegetation increased, but groundwater NO3- concentrations remained elevated because groundwater has a longer residence time. As a result streamwater NO3- concentrations had not fallen below preharvest levels, even during the growing season, 5 years after the harvest because of the contribution of groundwater to the stream. Streamwater NO3- and Alim concentrations increased more than reported in previous forest harvesting studies and the recovery was slower likely because the watershed has experienced several decades of acid deposition that has depleted initially base-poor soils of exchangeable base cations and caused long-term acidification of the soil. ?? 2007 Springer Science+Business Media B.V.

McHale, M.R.; Burns, D.A.; Lawrence, G.B.; Murdoch, P.S.

2007-01-01

103

Barium Ion Trapping Rebecca Schutzengel  

E-print Network

Barium Ion Trapping Rebecca Schutzengel Franklin W. Olin College of Engineering University of Washington INT REU August 20, 2012 Rebecca Schutzengel Barium Ion Trapping August 20, 2012 1 / 12 #12;Uses for Ion Trapping Bell's Inequality tests Quantum Computing Rebecca Schutzengel Barium Ion Trapping August

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

104

Observed Barium Emission Rates  

NASA Technical Reports Server (NTRS)

The barium releases from the CRRES satellite have provided an opportunity for verifying theoretically calculated barium ion and neutral emission rates. Spectra of the five Caribbean releases in the summer of 1991 were taken with a spectrograph on board a U.S. Air Force jet aircraft. Because the line of sight release densities are not known, only relative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other observations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with photometric observations. It has been postulated that charge exchange between neutral barium and oxygen ions represents a significant source for ionization. If so. it should be associated with emissions at 4957.15 A and 5013.00 A, but these emissions were not detected.

Stenbaek-Nielsen, H. C.; Wescott, E. M.; Hallinan, T. J.

1993-01-01

105

A CRITICAL EXAMINATION OF THE X-WIND MODEL FOR CHONDRULE AND CALCIUM-RICH, ALUMINUM-RICH INCLUSION FORMATION AND RADIONUCLIDE PRODUCTION  

SciTech Connect

Meteoritic data, especially regarding chondrules and calcium-rich, aluminum-rich inclusions (CAIs), and isotopic evidence for short-lived radionuclides (SLRs) in the solar nebula, potentially can constrain how planetary systems form. Interpretation of these data demands an astrophysical model, and the 'X-wind' model of Shu et al. and collaborators has been advanced to explain the origin of chondrules, CAIs, and SLRs. It posits that chondrules and CAIs were thermally processed <0.1 AU from the protostar, then flung by a magnetocentrifugal outflow to the 2-3 AU region to be incorporated into chondrites. Here we critically examine key assumptions and predictions of the X-wind model. We find a number of internal inconsistencies: theory and observation show no solid material exists at 0.1 AU; particles at 0.1 AU cannot escape being accreted into the star; particles at 0.1 AU will collide at speeds high enough to destroy them; thermal sputtering will prevent growth of particles; and launching of particles in magnetocentrifugal outflows is not modeled, and may not be possible. We also identify a number of incorrect predictions of the X-wind model: the oxygen fugacity where CAIs form is orders of magnitude too oxidizing, chondrule cooling rates are orders of magnitude lower than those experienced by barred olivine chondrules, chondrule-matrix complementarity is not predicted, and the SLRs are not produced in their observed proportions. We conclude that the X-wind model is not relevant to chondrule and CAI formation and SLR production. We discuss more plausible models for chondrule and CAI formation and SLR production.

Desch, S. J.; Morris, M. A. [School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287-1404 (United States); Connolly, H. C. [Kingsborough Community College and the Graduate Center of the City University of New York, 2001 Oriental Boulevard, Brooklyn, NY 11235-2398 (United States); Boss, Alan P., E-mail: steve.desch@asu.ed [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015-1305 (United States)

2010-12-10

106

21 CFR 82.2051 - Lakes (Ext. D&C).  

Code of Federal Regulations, 2012 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of...sodium, potassium, barium, or calcium; or (ii) a salt prepared from...potassium, aluminum, barium, calcium, strontium, or zirconium....

2012-04-01

107

21 CFR 82.2051 - Lakes (Ext. D&C).  

Code of Federal Regulations, 2011 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of...sodium, potassium, barium, or calcium; or (ii) a salt prepared from...potassium, aluminum, barium, calcium, strontium, or zirconium....

2011-04-01

108

21 CFR 82.2051 - Lakes (Ext. D&C).  

Code of Federal Regulations, 2014 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of...sodium, potassium, barium, or calcium; or (ii) a salt prepared from...potassium, aluminum, barium, calcium, strontium, or zirconium....

2014-04-01

109

21 CFR 82.2051 - Lakes (Ext. D&C).  

Code of Federal Regulations, 2013 CFR

...talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of...sodium, potassium, barium, or calcium; or (ii) a salt prepared from...potassium, aluminum, barium, calcium, strontium, or zirconium....

2013-04-01

110

Tailored Barium Swallow Study  

MedlinePLUS

Tailored Barium Swallow Study The TBS is a special study that is completed in radiology. The test evaluates the mouth and the throat ... and may be asked to feed the child. Study Participants You/Your child will drink liquids or ...

111

Semiconducting barium titanate  

Microsoft Academic Search

Barium titanate, which is well known as a basic ferroelectric material, is also of interest when doped because of the interaction between semiconductivity and ferroelectricity. The resistance of blocking layers at surfaces and grain-boundaries is governed mainly by the ferroelectric properties, so that a resistance jump of four decades is observed on heating above the Curie temperature. A survey of

W. Heywang

1971-01-01

112

Silico-ferrite of Calcium and Aluminum (SFCA) Iron Ore Sinter Bonding Phases: New Insights into Their Formation During Heating and Cooling  

NASA Astrophysics Data System (ADS)

The formation of silico-ferrite of calcium and aluminum (SFCA) and SFCA-I iron ore sinter phases during heating and cooling of synthetic iron ore sinter mixtures in the range 298 K to 1623 K (25 °C to 1350 °C) and at oxygen partial pressure of 5 × 10-3 atm has been characterized using in situ synchrotron X-ray diffraction. SFCA and SFCA-I are the key bonding phases in iron ore sinter, and an improved understanding of their formation mechanisms may lead to improved efficiency of industrial sintering processes. During heating, SFCA-I formation at 1327 K to 1392 K (1054 °C to 1119 °C) (depending on composition) was associated with the reaction of Fe2O3, 2CaO·Fe2O3, and SiO2. SFCA formation (1380 K to 1437 K [1107 °C to 1164 °C]) was associated with the reaction of CaO·Fe2O3, SiO2, and a phase with average composition 49.60, 9.09, 0.14, 7.93, and 32.15 wt pct Fe, Ca, Si, Al, and O, respectively. Increasing Al2O3 concentration in the starting sinter mixture increased the temperature range over which SFCA-I was stable before the formation of SFCA, and it stabilized SFCA to a higher temperature before it melted to form a Fe3O4 + melt phase assemblage (1486 K to 1581 K [1213 °C to 1308 °C]). During cooling, the first phase to crystallize from the melt (1452 K to 1561 K [1179 °C to 1288 °C]) was an Fe-rich phase, similar in composition to SFCA-I, and it had an average composition 58.88, 6.89, 0.82, 3.00, and 31.68 wt pct Fe, Ca, Si, Al, and O, respectively. At lower temperatures (1418 K to 1543 K [1145 °C to 1270 °C]), this phase reacted with melt to form SFCA. Increasing Al2O3 increased the temperature at which crystallization of the Fe-rich phase occurred, increased the temperature at which crystallization of SFCA occurred, and suppressed the formation of Fe2O3 (1358 K to 1418 K [1085 °C to 1145 °C]) to lower temperatures.

Webster, Nathan A. S.; Pownceby, Mark I.; Madsen, Ian C.; Kimpton, Justin A.

2012-12-01

113

Samarium-neodymium chronology and rubidium-strontium systematics of an Allende calcium-aluminum-rich inclusion with implications for 146Sm half-life  

NASA Astrophysics Data System (ADS)

Calcium-aluminum-rich inclusions (CAIs) are primitive objects that formed within the protoplanetary disk surrounding the young Sun. Recent Pb-Pb chronologic studies have demonstrated that CAIs are the oldest solar system solids, crystallizing 4567 Ma ago (Amelin et al., 2002; Connelly et al., 2012). The isotope systematics of CAIs therefore provide critical insight into the earliest history of the Solar System. Although Sm-Nd and Rb-Sr geochronometers are highly effective tools for investigating cosmochemical evolution in the early Solar System, previous studies of CAIs have revealed evidence for isotopically disturbed systems. Here we report new age data for Allende CAI Al3S4 derived from both the long-lived (147Sm-143Nd) and short-lived (146Sm-142Nd) isotopic systems. The 147Sm-143Nd chronometer yields an age of 4560±34 Ma that is concordant with 207Pb-206Pb ages for CAIs and indicates that the Sm-Nd system was not significantly disturbed by secondary alteration or nucleosynthetic processes. The slope of the 146Sm-142Nd isochron defines the Solar System initial 146Sm/144Sm of 0.00828±0.00044. This value is significantly different from the value of 0.0094 determined by Kinoshita et al. (2012). Ages recalculated from all published 146Sm-142Nd isochron data using the traditional 103 Ma half-life and the initial 146Sm/144Sm value determined here closely match Pb-Pb and 147Sm-143Nd ages determined on the same samples. In contrast, ages recalculated using the 68 Ma half-life determined by Kinoshita et al. (2012) and either of the initial 146Sm/144Sm values are often anomalously old. This is particularly true for the youngest samples with 146Sm-142Nd isochron ages that are most sensitive to the choice of 146Sm half-life used in the age calculation. In contrast to the Sm-Nd isotope system, the Rb-Sr system is affected by alteration but yields an apparent isochron with a slope corresponding to a much younger age of 4247±110 Ma. Although the Rb-Sr system in CAIs appears to be disturbed, the initial 87Sr/86Sr value determined from the isochron is 0.698942±0.000008, and closely approximates estimates of the initial Solar System value. Although this isochron may be a mixing line, it might also record alteration on the Allende parent body in which Rb was added to the Al3S4 CAI that was initially largely devoid of Rb.

Marks, N. E.; Borg, L. E.; Hutcheon, I. D.; Jacobsen, B.; Clayton, R. N.

2014-11-01

114

An Improved Qualitative Analysis Procedure for Aluminum Subgroup Cations.  

ERIC Educational Resources Information Center

Describes a procedure for the qualitative analysis of aluminum subgroup cations designed to avoid failure to obtain lead or barium chromate precipitates or failure to report aluminum hydroxide when present (due to staining). Provides a flow chart and step-by-step explanation for the new procedure, indicating significantly improved student results.…

Kistner, C. R.; Robinson, Patricia J.

1983-01-01

115

The high-temperature sulphation behavior of barium-based sorbents during coal combustion  

SciTech Connect

In order to promote the sulfur removal efficiency during coal combustion, the high-temperature sulfation behavior of barium-based sorbents was studied. The sulfation product BaSO{sub 4} which did not decompose until 1,580 C had much better thermal stability than CaSO{sub 4} which rapidly decomposed at about 1,300 C. The desulfurization effect of barium salt Ba{sup 2+} was much better than calcium salt Ca{sup 2+} during coal combustion at about 1,200{approximately}1,300 C. The sulfur removal efficiency of barium-based sorbents could achieve 35.5% in industrial grate furnace.

Cheng, J.; Li, N.; Zhou, J.; Cao, X.; Liu, J.; Zhao, X.; Cen, K.

2000-07-01

116

Silicosis in barium miners.  

PubMed Central

Four men who mined barytes in Scotland and who developed pneumoconiosis are described. Three developed progressive massive fibrosis, from which two died; and one developed a nodular simple pneumoconiosis after leaving the industry. The radiological and pathological features of the men's lungs were those of silicosis and high proportions of quartz were found in two of them post mortem. The quartz was inhaled from rocks associated with the barytes in the mines. The features of silicosis in barium miners are contrasted with the benign pneumoconiosis, baritosis, that occurs in workers exposed to crushed and ground insoluble barium salts. Diagnostic difficulties arise when silicosis develops in workers mining minerals known to cause a separate and benign pneumoconiosis. These difficulties are compounded when, as not infrequently happens, the silicotic lesions develop or progress after exposure to quartz has ceased. Images PMID:3787542

Seaton, A; Ruckley, V A; Addison, J; Brown, W R

1986-01-01

117

75 FR 33824 - Barium Chloride From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...No. 731-TA-149 (Third Review)] Barium Chloride From China Determination On the...revocation of the antidumping duty order on barium chloride from China would be likely to...Publication 4157 (June 2010), entitled Barium Chloride from China: Investigation...

2010-06-15

118

75 FR 19657 - Barium Chloride From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...No. 731-TA-149 (Third Review)] Barium Chloride From China AGENCY: United States...concerning the antidumping duty order on barium chloride from China...revocation of the antidumping duty order on barium chloride from China would be likely...

2010-04-15

119

Properties of Semiconductive Barium Titanates  

Microsoft Academic Search

The resistivity of barium titanate which is usually of the order of 109˜1012 ohm-cm, may be remarkably reduced with suitable control in valency. The valency-controlled barium titanate, whose resistivity is of the order of 10˜104 ohm-cm at room temperature, shows anomalous positive character in the temperature dependency of the resistivity. For example, the resistivity of barium titanate containing 0.1 mol.

Osamu Saburi

1959-01-01

120

Lack of effect of drinking water barium on cardiovascular risk factors  

SciTech Connect

Higher cardiovascular mortality has been associated in a single epidemiological study with higher levels of barium in drinking water. The purpose of this study was to determine whether drinking water barium at levels found in some U.S. communities-alters the known risk factors for cardiovascular disease. Eleven healthy men completed a 10-week dose-response protocol in which diet was controlled. Other aspects of the subjects' lifestyles known to affect cardiac risk factors were controlled, and the barium content (as barium chloride) of the drinking water was varied from 0, to 5 ppm, to 10 ppm. Multiple blood and urine samples, morning and evening blood pressure measurements, and 48-hr electrocardiographic monitoring were performed at each dose of barium. There were no changes in morning or evening systolic or diastolic blood pressures, plasma cholesterol or lipoprotein or apolipoprotein levels, serum potassium or glucose levels, or urine catecholamine levels. There were no arrythmias related to barium exposure detected on continuous electrocardiographic monitoring. A trend was seen toward increased total serum calcium levels with exposure to barium, which was of borderline statistical significance and of doubtful clinical significance. In summary, drinking water barium at levels of 5 and 10 ppm did not appear to affect any of the known modifiable cardiovascular risk factors.

Wones, R.G.; Stadler, B.L.; Frohman, L.A. (Univ. of Cincinnati College of Medicine, OH (USA))

1990-04-01

121

Barium uranyl diphosphonates  

SciTech Connect

Three Ba{sup 2+}/UO{sub 2}{sup 2+} methylenediphosphonates have been prepared from mild hydrothermal treatment of uranium trioxide, methylendiphosphonic acid (C1P2) with barium hydroxide octahydrate, barium iodate monohydrate, and small aliquots of HF at 200 Degree-Sign C. These compounds, Ba[UO{sub 2}[CH{sub 2}(PO{sub 3}){sub 2}]{center_dot}1.4H{sub 2}O (Ba-1), Ba{sub 3}[(UO{sub 2}){sub 4}(CH{sub 2}(PO{sub 3}){sub 2}){sub 2}F{sub 6}]{center_dot}6H{sub 2}O (Ba-2), and Ba{sub 2}[(UO{sub 2}){sub 2}(CH{sub 2}(PO{sub 3}){sub 2})F{sub 4}]{center_dot}5.75H{sub 2}O (Ba-3) all adopt layered structures based upon linear uranyl groups and disphosphonate molecules. Ba-2 and Ba-3 are similar in that they both have UO{sub 5}F{sub 2} pentagonal bipyramids that are bridged and chelated by the diphosphonate moiety into a two-dimensional zigzag anionic sheet (Ba-2) and a one-dimensional ribbon anionic chain (Ba-3). Ba-1, has a single crystallographically unique uranium metal center where the C1P2 ligand solely bridges to form [UO{sub 2}[CH{sub 2}(PO{sub 3}){sub 2}]{sup 2-} sheets. The interlayer space of the structures is occupied by Ba{sup 2+}, which, along with the fluoride ion, mediates the structure formed and maintains overall charge balance. - Graphical abstract: Illustration of the stacking of the layers in Ba{sub 3}[(UO{sub 2}){sub 4}(CH{sub 2}(PO{sub 3}){sub 2}){sub 2})F{sub 6}]{center_dot}6H{sub 2}O viewed along the c-axis. The structure is constructed from UO{sub 7} pentagonal bipyramidal units, U(1)O{sub 7}=gray, U(2)O{sub 7}=yellow, barium=blue, phosphorus=magenta, fluorine=green, oxygen=red, carbon=black, and hydrogen=light peach. Highlights: Black-Right-Pointing-Pointer The polymerization of the UO{sub 2}{sup 2+} sites to form uranyl dimers leads to structural variations in compounds. Black-Right-Pointing-Pointer Barium cations stitch uranyl diphosphonate anionic layers together, and help mediate structure formation. Black-Right-Pointing-Pointer HF acts as both a mineralizing agent and a ligand.

Nelson, Anna-Gay D., E-mail: nelsoa@umich.edu [Department of Civil Engineering and Geological Sciences and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109-1005 (United States); Alekseev, Evgeny V. [Institute of Energy and Climate Research (IEK-6), Forschungszentrum Juelich Wilhelm-Johnen-Strasse, Juelich 52428 (Germany); Ewing, Rodney C. [Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109-1005 (United States); Albrecht-Schmitt, Thomas E. [Department of Civil Engineering and Geological Sciences and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States)

2012-08-15

122

21 CFR 82.1051 - Lakes (D&C).  

Code of Federal Regulations, 2010 CFR

...radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium; or (ii) a salt prepared from one of...radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2) Specifications. Ether...

2010-04-01

123

Formation of ettringite, Ca 6Al 2(SO 4) 3(OH) 12·26H 2O, AFt, and monosulfate, Ca 4Al 2O 6(SO 4)·14H 2O, AFm-14, in hydrothermal hydration of Portland cement and of calcium aluminum oxide—calcium sulfate dihydrate mixtures studied by in situ synchrotron X-ray powder diffraction  

NASA Astrophysics Data System (ADS)

In the hydration of calcium aluminum oxide-gypsum mixtures, i.e., Ca 3Al 2O 6, Ca 12Al 14O 33 and CaSO 4·2H 2O, the reaction products can be ettringite, Ca 6Al 2(SO 4) 3(OH) 12·26H 2O, monosulfate, Ca 4Al 2O 6(SO 4)·14H 2O, or the calcium aluminum oxide hydrate, Ca 4Al 2O 7·19H 2O. Ettringite is formed if sufficient CaSO 4·2H 2O is present in the mixture. Ettringite is converted to monosulfate when all CaSO 4·2H 2O is consumed in the synthesis of ettringite. The reactions were investigated in the temperature range 25-170°C using in situ synchrotron X-ray powder diffraction. This technique allows the study of very fast chemical reactions that are observed here under hydrothermal conditions. A new experimental approach was developed to perform in situ mixing of the reactants during X-ray data collection.

Christensen, Axel Nørlund; Jensen, Torben R.; Hanson, Jonathan C.

2004-06-01

124

Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum  

SciTech Connect

Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi

2007-08-16

125

Uranium Sequestration by Aluminum Phosphate Minerals in Unsaturated Soils  

SciTech Connect

A mineralogical and geochemical study of soils developed from the unmined Coles Hill uranium deposit (Virginia) was undertaken to determine how phosphorous influences the speciation of uranium in an oxidizing soil/saprolite system typical of the eastern United States. This paper presents mineralogical and geochemical results that identify and quantify the processes by which uranium has been sequestered in these soils. It was found that uranium is not leached from the saturated soil zone (saprolites) overlying the deposit due to the formation of a sparingly soluble uranyl phosphate mineral of the meta-autunite group. The concentration of uranium in the saprolites is approximately 1000 mg uranium per kg of saprolite. It was also found that a significant amount of uranium was retained in the unsaturated soil zone overlying uranium-rich saprolites. The uranium concentration in the unsaturated soils is approximately 200 mg uranium per kg of soil (20 times higher than uranium concentrations in similar soils adjacent to the deposit). Mineralogical evidence indicates that uranium in this zone is sequestered by a barium-strontium-calcium aluminum phosphate mineral of the crandallite group (gorceixite). This mineral is intimately inter-grown with iron and manganese oxides that also contain uranium. The amount of uranium associated with both the aluminum phosphates (as much as 1.4 weight percent) has been measured by electron microprobe micro-analyses and the geochemical conditions under which these minerals formed has been studied using thermodynamic reaction path modeling. The geochemical data and modeling results suggest the meta-autunite group minerals present in the saprolites overlying the deposit are unstable in the unsaturated zone soils overlying the deposit due to a decrease in soil pH (down to a pH of 4.5) at depths less than 5 meters below the surface. Mineralogical observations suggest that, once exposed to the unsaturated environment, the meta-autunite group minerals react to form U(VI)- bearing aluminum phosphates. (author)

Jerden, James L. Jr. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL, 60439 (United States)

2007-07-01

126

Discovery of the Barium Isotopes  

E-print Network

Thirty-eight barium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

A. Shore; A. Fritsch; J. Q. Ginepro; M. Heim; A. Schuh; M. Thoennessen

2009-08-13

127

Discovery of the barium isotopes  

SciTech Connect

Thirty-eight barium isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

Shore, A.; Fritsch, A.; Ginepro, J.Q.; Heim, M.; Schuh, A. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Thoennessen, M., E-mail: thoennessen@nscl.msu.ed [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

2010-11-15

128

FLAME SPECTROPHOTOMETRIC STUDY OF BARIUM  

Microsoft Academic Search

Flame emission characteristics of the barium ionic doublet at 455.4 and ; 4193.4 m mu , the atomic resonance line at 553.6 m mu , and the BaOH and BaO ; bands at 489 and 513 m mu were studied. A prism flame spectrophotometer ; (Beckman DU) and a grating type (Jarrell-Ash Ebert) were used. Barium ; concentrations ranged from

J. C. Burger; T. C. Rains; H. E. Zittel; J. A. Dean

1961-01-01

129

Large-volume barium aspiration.  

PubMed

We present a case of large-volume barium aspiration in a 56-year-old woman with stage IV tongue squamous cell carcinoma and longstanding dysphagia. The patient rapidly developed hypoxemic respiratory failure from the resultant chemical pneumonitis. However, her respiratory status improved with supportive care alone in 48 hours. Barium aspiration is rare and often produces dramatic radiographic findings, but is generally associated with a favorable prognosis. PMID:25829647

Hundemer, Gregory L; Kumar, Varun; Vaduganathan, Muthiah

2015-04-01

130

Large-volume barium aspiration  

PubMed Central

We present a case of large-volume barium aspiration in a 56-year-old woman with stage IV tongue squamous cell carcinoma and longstanding dysphagia. The patient rapidly developed hypoxemic respiratory failure from the resultant chemical pneumonitis. However, her respiratory status improved with supportive care alone in 48 hours. Barium aspiration is rare and often produces dramatic radiographic findings, but is generally associated with a favorable prognosis. PMID:25829647

Hundemer, Gregory L.; Kumar, Varun

2015-01-01

131

Barium light source method and apparatus  

NASA Technical Reports Server (NTRS)

Visible light emission is obtained from a plasma containing elemental barium including neutral barium atoms and barium ion species. Neutral barium provides a strong green light emission in the center of the visible spectrum with a highly efficient conversion of electrical energy into visible light. By the selective excitation of barium ionic species, emission of visible light at longer and shorter wavelengths can be obtained simultaneously with the green emission from neutral barium, effectively providing light that is visually perceived as white. A discharge vessel contains the elemental barium and a buffer gas fill therein, and a discharge inducer is utilized to induce a desired discharge temperature and barium vapor pressure therein to produce from the barium vapor a visible light emission. The discharge can be induced utilizing a glow discharge between electrodes in the discharge vessel as well as by inductively or capacitively coupling RF energy into the plasma within the discharge vessel.

Curry, John J. (Inventor); MacDonagh-Dumler, Jeffrey (Inventor); Anderson, Heidi M. (Inventor); Lawler, James E. (Inventor)

2002-01-01

132

Calcium Phosphate Nanoparticle Adjuvant  

Microsoft Academic Search

Vaccination to protect against human infectious diseases may be enhanced by using adjuvants that can selec- tively stimulate immunoregulatory responses. In a murine model, a novel nanoparticulate adjuvant composed of calcium phosphate (CAP) was compared with the commonly used aluminum (alum) adjuvants for its ability to induce immunity to herpes simplex virus type 2 (HSV-2) and Epstein-Barr virus (EBV) infections.

QING HE; ALAINA R. MITCHELL; STACY L. JOHNSON; CLAUS WAGNER-BARTAK; TULIN MORCOL; STEVE J. D. BELL

2000-01-01

133

Abundance analysis of barium and mild barium stars  

E-print Network

High signal to noise, high resolution spectra were obtained for a sample of normal, mild barium, and barium giants. Atmospheric parameters were determined from the FeI and FeII lines. Abundances for Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu, and Gd, were determined from equivalent widths and model atmospheres in a differential analysis, with the red giant Eps Vir as the standard star. The different levels of s-process overabundances of barium and mild barium stars were earlier suggested to be related to the stellar metallicity. Contrary to this suggestion, we found in this work no evidence of barium and mild barium to having different range in metallicity. However, comparing the ratio of abundances of heavy to light s-process elements, we found some evidence that they do not share the same neutron exposure parameter. The exact mechanism controlling this difference is still not clear. As a by-product of this analysis we identify two normal red giants misclassified as mild barium stars. The relevance of this finding is discussed. Concerning the suggested nucleosynthetic effects possibly related to the s-process, for elements like Cu, Mn, V and Sc, we found no evidence for an anomalous behavior in any of the s-process enriched stars analyzed here. However, further work is still needed since a clear [Cu/Fe] vs. [Ba/H] anticorrelation exists for other s-process enriched objects.

R. Smiljanic; G. F. Porto de Mello; L. da Silva

2007-04-02

134

Barium and CH Stars The classical barium (or ``Ba II'') stars are red  

E-print Network

Barium and CH Stars The classical barium (or ``Ba II'') stars are red giants whose spectra show strong absorption lines of barium, strontium, and certain other heavy elements, as well as strong transfer in binary sys­ tems that drastically alters the surface compo­ sition of a companion star. Barium

Bond, Howard E.

135

Aluminum Hydroxide  

MedlinePLUS

Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

136

Fully-Ionized Barium Plasma Source  

Microsoft Academic Search

A device for generating a fully-ionized barium plasma column is described. It is similar to the previously described Q1 device except for the substitution of rhenium ionizing surfaces for tungsten, and barium for the alkali metals. The main motivation for the use of barium is that singly-ionized barium has its resonance lines in the visible wavelength range, and thus allows

N. Rynn; E. Hinnov; L. C. Johnson

1967-01-01

137

Barium Ions for Quantum Computation Matthew Dietrich  

E-print Network

Barium Ions for Quantum Computation Matthew Dietrich A dissertation submitted in partial of the manuscript made from microform." Signature Date #12;#12;University of Washington Abstract Barium Ions Department of Physics Barium ion is investigated as a hyperfine qubit. 137Ba+ is trapped in a linear Paul

Blinov, Boris

138

Quantum manipulation on the Barium quadrupolar transition  

E-print Network

Quantum manipulation on the Barium quadrupolar transition A diploma thesis in physics submitted and stabilization of a new fiber laser system to ma- nipulate the Barium quadrupolar transition, with the aim with a single Barium ion trapped in a linear Paul trap and Doppler cooled to the Lamb Dicke regime. The narrow

Blatt, Rainer

139

Determination of barium and strontium peroxides (active oxygen) in igniters in small-arms tracer ammunition.  

PubMed

A method is proposed for the determination of barium and strontium peroxides (active oxygen) in igniters in small-arms tracer ammunition. The sample is treated with dilute hydrochloric acid (1 + 9) which dissolves the magnesium powder almost instantaneously and then dissolves the barium or strontium peroxides within 10-30 min. The solution is then filtered to remove the organic substances (calcium resinate, "Parlon". Toluidine Red toner, and zinc stearate) and the peroxide is determined by means of the colour of the titanium-peroxide complex. It is shown that igniter mixes and igniters used in small-arms tracer ammunition deteriorate on storage. PMID:18961958

Norwitz, G; Galan, M

1976-09-01

140

Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water  

PubMed Central

Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (?700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system. PMID:23805262

Kato, Masashi; Kumasaka, Mayuko Y.; Ohnuma, Shoko; Furuta, Akio; Kato, Yoko; Shekhar, Hossain U.; Kojima, Michiyo; Koike, Yasuko; Dinh Thang, Nguyen; Ohgami, Nobutaka; Ly, Thuy Bich; Jia, Xiaofang; Yetti, Husna; Naito, Hisao; Ichihara, Gaku; Yajima, Ichiro

2013-01-01

141

Computer modelling of barium titanate  

Microsoft Academic Search

Barium titanate is an important material for both scientific and industrial applications. Much of the interest centres around its ferroelectric properties, since it is structurally the most simple in this class. In addition rare-earth doped ceramics are found to exhibit a very steep positive temperature coefficient of resistance (PTCR) above the Curie point. The theory of this PTCR effect is

G. V. Lewis; C. R. A. Catlow

1983-01-01

142

Are There Any Stars Lacking Neutron-Capture Elements? Evidence from Strontium and Barium  

E-print Network

The cosmic dispersion in the abundances of the heavy elements strontium and barium in halo stars is well known. Strontium and barium are detected in most cool, metal-poor giants, but are these elements always detectable? To identify stars that could be considered probable candidates for lacking these elements, I examine the stellar abundance data available in the literature for 1148 field stars and 226 stars in dwarf galaxies, 776 of which have metallicities lower than [Fe/H]barium have been detected in all field, globular cluster, and dwarf galaxy environments studied. All upper limits are consistent with the lowest detected ratios of [Sr/H] and [Ba/H]. The frequent appearance of these elements raises the intriguing prospect that at least one kind of neutron-capture reaction operates as often as the nucleosynthesis mechanisms that produce lighter elements, like magnesium, calcium, or iron, although the yields of heavy elements may be more variable.

Roederer, Ian U

2012-01-01

143

Superconductivity of strontium aluminum germanide and barium aluminum germanide Structure and Dynamics of strontium aluminum germanium hydride and barium aluminum germanium hydride  

Microsoft Academic Search

The discovery of the superconductor MgB2 led to the increase of research activity for more compounds adopting the AlB 2 structure type and containing superconductive properties. The prominent successor compounds were the silicide systems, AeAlSi (Ae=Sr, Ba, Ca). Presented here is an extension of this investigation to the germanides, SrAlGe and BaAlGe. The ternary structures were synthesized through arc-melting elemental

Verina Franika Kranak

2011-01-01

144

Calcium nutrition of Sphaerotilus growing in a continuous-flow apparatus.  

PubMed

Sphaerotilus natans required calcium for the production of sheaths and probably requires calcium for growth as well, though at a lower concentration. Neither strontium nor barium substituted for calcium. S. natans grew attached to the culture vessels of the continuous-flow apparatus even when no sheaths were produced. Tentative evidence showed that the requirement for calcium is shared by the manganese-oxidizing species S. discophorus. PMID:4970993

Dias, F F; Okrend, H; Dondero, N C

1968-09-01

145

Aluminum Boats  

NSDL National Science Digital Library

Test the buoyancy of an aluminum foil boat and an aluminum foil ball. Why does the same material in different shapes sink or float? This activity explores the fact that the amount of water pushed aside by an object equals the force of water pushing upward on the object.

Reuben H. Fleet Science Center

1999-01-01

146

Surface Electrical Properties of Barium Sulfate Modified by Adsorption of Poly alpha, beta Aspartic Acid.  

PubMed

The surface electrical properties of precipitated barium sulfate in aqueous solution have been probed in the presence and absence of synthetic poly alpha, beta aspartic acid. The effect of cation type, ion concentration, and pH on the electrokinetic properties of barite with and without adsorbed polyaspartic acid has been analyzed to afford insights into the mechanism by which polyaspartic acid acts as an inhibitor of barium sulfate precipitation. In addition, vibrational spectroscopy has been employed to monitor bond changes within polyaspartic acid molecules adsorbed on precipitated barium sulfate. These studies have indicated that the surface electrical charge of "pure" barite differs significantly from that of barite precipitated in the presence of calcium ions. Moreover, the presence of the cations Ca2+ and Mg2+ in the suspending liquor has a marked influence of the measured electrokinetic properties. The infrared spectral studies strongly suggest that polyaspartic acid is bound to the barite via the backbone nitrogen atoms. This proposal in conjunction with the electrokinetic and adsorption data has allowed a tentative model of barium sulfate inhibition to be proposed; viz, calcium ions are needed to complex with the polyaspartic acid, first, to reduce the molecules electrical charge in order to promote adsorption onto a charged surface; second, to induce a conformational change in the molecule in order to allow optimal anchoring via the backbone nitrogen atoms; and, third, to reduce the solubility of the molecule in order to increase its surface activity. Copyright 1999 Academic Press. PMID:10092385

Collins

1999-04-15

147

Investigations on Barium Ferrite Magnets  

Microsoft Academic Search

Barium ferrite (BaO:6Fe2O3) has been investigated magnetically to test the predictions of fine particle theory in the region of grain sizes larger than the critical one for which no satisfactory theory exists as yet. Grain size and coercive force of polycrystalline magnets (nonoriented and crystal oriented) were closely related to sintering temperatures. A comparison of theoretical and observed temperature dependence

K. J. Sixtus; K. J. Kronenberg; R. K. Tenzer

1956-01-01

148

The problem of the barium stars  

NASA Technical Reports Server (NTRS)

Ultraviolet observations of barium stars and other cool stars with peculiar element abundances are reported. Those observations attempted to find hot white dwarf companions. Among six real barium stars studied, only Zeta Cap was found to have a white dwarf companion. Among seven mild, or marginal, barium stars studied, at least three were found to have hot subluminous companions. It is likely that all of them have white dwarf companions.

Bohm-Vitense, E.; Nemec, J.; Proffitt, C.

1984-01-01

149

Calcium - urine  

MedlinePLUS

... best treatment for the most common type of kidney stone , which is made of calcium. This type of ... the kidneys into the urine, which causes calcium kidney stones Sarcoidosis Taking too much calcium Too much production ...

150

Calcium Carbonate  

MedlinePLUS

Calcium carbonate is a dietary supplement used when the amount of calcium taken in the diet is not ... for healthy bones, muscles, nervous system, and heart. Calcium carbonate also is used as an antacid to relieve ...

151

Calcium supplements  

MedlinePLUS

... enough calcium over your lifetime can help prevent osteoporosis . Most people get enough calcium in their normal diet. Calcium is found in dairy foods and leafy green vegetables. Older women and men ...

152

75 FR 20625 - Barium Chloride From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-149 (Third Review)] Barium Chloride From China AGENCY: United States International Trade Commission. ACTION: Revised schedule for the subject...

2010-04-20

153

Characterization of Medicago truncatula reduced calcium oxalate crystal mutant alleles  

Technology Transfer Automated Retrieval System (TEKTRAN)

Calcium oxalate crystal formation is common in plants. Formation of these crystals has been shown to function in plant defense, calcium regulation, and aluminum tolerance. Although calcium oxalate is common and plays important roles in plant development, our understanding of how these crystals form ...

154

Sol-gel synthesis of barium titanate powders using barium acetate and titanium(IV) isopropoxide  

SciTech Connect

A sol-gel process for low-temperature preparation of BaTiO{sub 3} powders is described. Chemical polymerization between barium acetate and titanium(IV) isopropoxide leads to the formation of barium titanate gels. After suitable drying and calcination treatments, the barium titanate gels were converted to BaTiO{sub 3} powders. The barium titanate gels and powders were characterized by TGA, DTA, and XRD. The results of these analyses indicate that it is possible to obtain stoichiometric (Ba/Ti = 0.99), homogeneous, high-purity BaTiO{sub 3} powders using relatively inexpensive barium acetate as a starting material.

Phule, P.P.; Risbud, S.H. (Univ. of Arizona, Tucson (USA))

1988-03-01

155

Aluminum Analysis.  

ERIC Educational Resources Information Center

Presents three problems based on the price of aluminum designed to encourage students to be cooperative and to use an investigative approach to learning. Students collect and synthesize information, analyze results, and draw conclusions. (AIM)

Sumrall, William J.

1998-01-01

156

Noise characterisation of barium ferrite dispersions  

Microsoft Academic Search

Structural changes in barium ferrite dispersions during the milling process have been investigated by using noise measurements of the remanent states (DC modulation noise). Doped barium ferrite particles mixed with solvents, self wetting resins and binders were dispersed using a bead mill. Samples extracted at intervals during the process were coated onto PET film and magnetically oriented before drying. Tapes

S. M. McCann; P. M. Sollis; P. R. Bissell; T. Onions

1999-01-01

157

REMOVAL OF BARIUM AND RADIUM FROM GROUNDWATER  

EPA Science Inventory

A research project was undertaken to investigate processes for removing barium and radium from drinking water. Special emphasis was placed on ion exchange processes that can be used without adding large concentrations of sodium to the water. The wastes from radium and barium remo...

158

Tribological properties of barium ferrite films  

Microsoft Academic Search

Acoustic emission and friction coefficients have been measured during start-stop and continuous sliding for pure and doped barium ferrite films, without lubrication, and compared with concomitant surface topography and magnetic properties. Barium ferrite films averaging about 100 nm in thickness, were produced on thermally oxidized Si substrates by sputter deposition and then furnace or rapid thermal annealed in order to

M. Scherge; X. Sui; X. Ma; C. L. Bauer; M. S. Jhon; M. H. Kryder

1995-01-01

159

Laser Welding of Aluminum and Aluminum Alloys  

E-print Network

.. ) Laser Welding of Aluminum and Aluminum Alloys Welds made with sharp bevel-groove weld aluminum and by aluminum alloy 5456 have been studied. The results indicate that initial absorption varies of the most dramatic illustrations of the differences in beam characteristics occurs when welding aluminum

Eagar, Thomas W.

160

Communications to the Editor Synthesis of Monodisperse Nanoparticles of Barium  

E-print Network

Communications to the Editor Synthesis of Monodisperse Nanoparticles of Barium Titanate: Toward of barium titanate, BaTiO3, with diameters ranging from 6 to 12 nm. Barium titanate is a room,10 In the synthesis developed here, barium titanium ethyl hexano-isopropoxide (A

161

Aluminum alloy  

NASA Technical Reports Server (NTRS)

This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

Blackburn, Linda B. (inventor); Starke, Edgar A., Jr. (inventor)

1989-01-01

162

Rapid communication Quantication of ve-and six-coordinated aluminum ions in  

E-print Network

Rapid communication Quanti®cation of ®ve- and six-coordinated aluminum ions in aluminosilicate, Stanford, CA 94305-2115, USA Received 5 May 2000 Abstract Aluminum cation sites with ®ve (5 Al) or six (6 in a calcium-aluminosilicate glass without excess aluminum over charge-balancing cations, and quantify small

Puglisi, Joseph

163

Magnetic and dielectric properties of barium titanate-coated barium ferrite  

Microsoft Academic Search

Flaky barium ferrite with hexagonal molecular structure was successfully prepared by reverse microemulsion method, and was coated with barium titanate through a coordination–precipitation technique. The prepared composite particles were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), vibrating sample magnetometry (VSM) and vector network analyzer. Barium ferrite nanoparticles are proved to be single magnetic

Chao Wang; Xijiang Han; Ping Xu; Xiaohong Wang; Xueai Li; Hongtao Zhao

2009-01-01

164

Distribution and source of barium in ground water at Cattaraugus Indian Reservation, southwestern New York  

USGS Publications Warehouse

High concentrations of dissolved barium have been found in ground water from bedrock wells on the Seneca Nation of Indians Reservation on Cattaraugus Creek in southwestern New York. Concentrations in 1982 were as high as 23.0 milligrams per liter , the highest found reported from any natural ground-water system in the world. The highest concentrations are in a bedrock aquifer and in small lenses of saturated gravel between bedrock and the overlying till. The bedrock aquifer is partly confined by silt, clay, and till. The high barium concentrations are attributed to dissolution of the mineral barite (BaSO4), which is present in the bedrock and possibly in overlying silt, clay, or till. The dissolution of barite seems to be controlled by action of sulfate-reducing bacteria, which alter the BaSO4 equilibrium by removing sulfate ions and permitting additional barite to dissolve. Ground water from the surficial, unconsolidated deposits and surface water in streams contain little or no barium. Because barium is chemically similar to calcium, it probably could be removed by cation exchange or treatments similar to those used for water softening. (USGS)

Moore, R.B.; Staubitz, W.W.

1984-01-01

165

Barium ions for quantum computation  

NASA Astrophysics Data System (ADS)

Barium ion is investigated as a hyperfine qubit. 137Ba + is trapped in a linear Paul trap and laser cooled. Isotope selective photoionization is employed to improve trapping from an isotopically inpure source. Optical pumping into the magnetically insensitive 2S 1/2(F=2) mF = 0 state is shown, and readout by electron shelving into the 2D5/2 is demonstrated both directly and by adiabatic passage. Rabi flops between the 2S1/2 F=1 and F=2 states is accomplished by exposure to 8.037 GHz microwave radiation. Several methods of locking the cooling lasers have been attempted and are discussed. Stabilization of the infrared laser used to drive the D 5/2 ? S1/2 transition is of particular interest, and several novel technologies are tested in this purpose.

Dietrich, Matthew

166

Abundance Analysis of Barium Stars  

E-print Network

We obtain the chemical abundances of six barium stars and two CH subgiant stars based on the high signal-to-noise ratio and high resolution Echelle spectra. The neutron capture process elements Y, Zr, Ba, La, Eu show obvious overabundance relative to the Sun, for example, their [Ba/Fe] values are from 0.45 to 1.27. Other elements, including Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Ni, show comparable abundances to the Solar ones, and their [Fe/H] cover a range from $-$0.40 to 0.21, which means they belong to Galactic disk. The predicts of the theoretical model of wind accretion for binary systems can explain the observed abundance patterns of the neutron capture process elements in these stars, which means that their overabundant heavy-elements could be caused by accreting the ejecta of AGB stars, the progenitors of the present white dwarf companions in the binary systems.

G. Q. Liu; Y. C. Liang; L. Deng

2008-11-13

167

Aluminum Cans  

NSDL National Science Digital Library

In this data analysis activity students investigate data in connection with recyclable materials and develop plans to help the environment. Students collect data about aluminum can usage and graph that data in a line plot. The lesson includes student worksheet and extension suggestions.

2008-01-01

168

Aluminum Pannier  

USGS Multimedia Gallery

This aluminum pannier was made for the storage of meat, vegetables and other food products. The pannier could be buried in the ground or placed in water in order to keep the contents cool. It was designed by Dr. J. D. Love and made for him in 1945. For transportation, this pannier, along with two re...

169

Cement-mortar pipes as a source of aluminum  

Microsoft Academic Search

In 1996 in Curaçao, acute aluminum (Al) intoxication sickened patients in a dialysis center that used tap water to prepare dialysate. The mortality rate was 32 percent. A new factory-lined cement-mortar water distribution pipe had recently been installed. It is known that substantial amounts of barium, cadmium, and chromium can leach from cement-mortar linings. This article shows that high concentrations

Kenrick Berend; Tom Trouwborst

1999-01-01

170

Barium Isotopes in Single Presolar Grains  

NASA Technical Reports Server (NTRS)

Barium isotopic compositions of single presolar grains were measured by laser ablation laser resonant ionization mass spectrometry and the implications of the data for stellar processes are discussed. Additional information is contained in the original extended abstract.

Pellin, M. J.; Davis, A. M.; Savina, M. R.; Kashiv, Y.; Clayton, R. N.; Lewis, R. S.; Amari, S.

2001-01-01

171

Point defects and properties of barium titanate  

SciTech Connect

The authors consider the simple case of uniformly distributed atomic point defects over the volume of a barium titanate crystal. The diversity of phenomena associated with the transport of electric charge in barium titanate is determined by the distinctive features of its point defects: the existence of two regions of disorder, one of which corresponds to a compensated semiconductor while the other corresponds to an uncompensated semiconductor and a difference in the kinetics of the relaxation of two types of dominant atomic defects, viz., oxygen and barium vacancies. The authors have made a quantitative examination of the interrelation between the conditions of the preparation of materials based on barium titanate and their electrical conductivity.

Prisedskii, V.V.; Tret'yakov, Y.D.

1986-01-01

172

Spinwave spectrum for barium ferrite (abstract)  

Microsoft Academic Search

In order to determine whether barium ferrite will be suitable for microwave and millimeter wave device applications, it is essential to calculate the intrinsic ferrimagnetic resonance linewidth for perfect single crystals of this compound. The two mechanisms believed to be responsible for the intrinsic linewidth of barium ferrite, the Kasuya–LeCraw1 two-magnon one-phonon process and the two-magnon scattering caused by the

S. P. Marshall; J. B. Sokoloff

1990-01-01

173

Fabrication of Barium Ferrite Thick Films  

Microsoft Academic Search

During recent years the need for high quality self-biased barium ferrite (BaFe12O19) thick films had been increasing due to its chemical stability, anisotropy and oriented hexagonal M-type ferrites. Our goal is to fabricate barium ferrite thick films to be incorporated in self-biased microwave devises. Different methods such as sputtering, pulse laser deposition, CVD and modified liquid phase deposition have been

Wei Jiang Yeh; Carla Blengeri-Oyarce; Sundeep Pillamari; Jnana Manoj Appikonda; Laura Diaz; Yanko Kranov; David McIlroy

2008-01-01

174

Dielectric and Piezoelectric Properties of Barium Titanate  

Microsoft Academic Search

The dielectric constant and loss of barium titanate and barium-strontium titanate have been measured at biasing field strengths from 0 to 5 megavolts per meter, at temperatures from -50°C to +135°C and at frequencies from 0.1 to 25 megacycles. The measurements versus temperature indicate the expected agreement with the Curie-Weiss law at temperatures above the Curie point. Measurements versus field

Shepard Roberts

1947-01-01

175

Thermochemical hydrogen production via a cycle using barium and sulfur - Reaction between barium sulfide and water  

NASA Technical Reports Server (NTRS)

The reaction between barium sulfide and water, a reaction found in several sulfur based thermochemical cycles, was investigated kinetically at 653-866 C. Gaseous products were hydrogen and hydrogen sulfide. The rate determining step for hydrogen formation was a surface reaction between barium sulfide and water. An expression was derived for the rate of hydrogen formation.

Ota, K.; Conger, W. L.

1977-01-01

176

Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage.  

PubMed

Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3). PMID:22233912

Mulopo, J; Zvimba, J N; Swanepoel, H; Bologo, L T; Maree, J

2012-01-01

177

21 CFR 82.3 - Definitions.  

Code of Federal Regulations, 2012 CFR

...suspension in water of precipitated aluminum hydroxide. (h) The term blanc fixe...in water of co-precipitated aluminum hydroxide and barium sulfate. (j...the sum of the quantities of aluminum, iron, calcium, and...

2012-04-01

178

21 CFR 82.3 - Definitions.  

Code of Federal Regulations, 2014 CFR

...suspension in water of precipitated aluminum hydroxide. (h) The term blanc fixe...in water of co-precipitated aluminum hydroxide and barium sulfate. (j...the sum of the quantities of aluminum, iron, calcium, and...

2014-04-01

179

21 CFR 82.3 - Definitions.  

Code of Federal Regulations, 2010 CFR

...suspension in water of precipitated aluminum hydroxide. (h) The term blanc fixe...in water of co-precipitated aluminum hydroxide and barium sulfate. (j...the sum of the quantities of aluminum, iron, calcium, and...

2010-04-01

180

21 CFR 82.3 - Definitions.  

Code of Federal Regulations, 2011 CFR

...suspension in water of precipitated aluminum hydroxide. (h) The term blanc fixe...in water of co-precipitated aluminum hydroxide and barium sulfate. (j...the sum of the quantities of aluminum, iron, calcium, and...

2011-04-01

181

21 CFR 82.3 - Definitions.  

Code of Federal Regulations, 2013 CFR

...suspension in water of precipitated aluminum hydroxide. (h) The term blanc fixe...in water of co-precipitated aluminum hydroxide and barium sulfate. (j...the sum of the quantities of aluminum, iron, calcium, and...

2013-04-01

182

Recycling of automotive aluminum  

Microsoft Academic Search

With the global warming of concern, the secondary aluminum stream is becoming an even more important component of aluminum production and is attractive because of its economic and environmental benefits. In this work, recycling of automotive aluminum is reviewed to highlight environmental benefits of aluminum recycling, use of aluminum alloys in automotive applications, automotive recycling process, and new technologies in

Jirang CUI; Hans J. ROVEN

2010-01-01

183

Temperature-dependent coherent oscillation in photorefractive relaxor strontium barium  

E-print Network

Temperature-dependent coherent oscillation in photorefractive relaxor strontium barium niobate M of the photorefractive light-induced scattering (beam fanning) in Sr0.61Ba0.39Nb2O6 (strontium barium niobate) doped

Osnabrück, Universität

184

Two barium stars in the Galactic bulge  

E-print Network

Barium stars conserve important information on the s-process and the third dredge-up in intermediate mass stars. Their discovery in various environments is therefore of great help to test nucleosynthesis and mixing models. Our aim is to analyse two stars with a very strong barium line detected in a large survey of red giants in the Galactic bulge. Abundance analysis was done comparing synthetic model spectra based on the COMARCS code with our medium resolution spectra. Abundances of Ba, La, Y, and Fe were determined. Beside the two main targets, the analysis was also applied to two comparison stars. We confirm that both stars are barium stars. They are the first ones of this kind identified in the Galactic bulge. Their barium excesses are among the largest values found up to now. The elemental abundances are compared with current nucleosynthesis and mixing models. Furthermore, we estimate a frequency of barium stars in the Galactic bulge of about 1%, which is identical to the value for disc stars.

Lebzelter, Thomas; Straniero, Oscar; Aringer, Bernhard

2013-01-01

185

Kinetic analysis of barium currents in chick cochlear hair cells.  

PubMed Central

Inward barium current (IBa) through voltage-gated calcium channels was recorded from chick cochlear hair cells using the whole-cell clamp technique. IBa was sensitive to dihydropyridines and insensitive to the peptide toxins omega-agatoxin IVa, omega-conotoxin GVIa, and omega-conotoxin MVIIC. Changing the holding potential over a -40 to -80 mV range had no effect on the time course or magnitude of IBa nor did it reveal any inactivating inward currents. The activation of IBa was modeled with Hodgkin-Huxley m2 kinetics. The time constant of activation, tau m, was 550 microseconds at -30 mV and gradually decreased to 100 microseconds at +50 mV. A Boltzmann fit to the activation curve, m infinity, yielded a half activation voltage of -15 mV and a steepness factor of 7.8 mV. Opening and closing rate constants, alpha m and beta m, were calculated from tau m and m infinity, then fit with modified exponential functions. The H-H model derived by evaluating the exponential functions for alpha m and beta m not only provided an excellent fit to the time course of IBa activation, but was predictive of the time course and magnitude of the IBa tail current. No differences in kinetics or voltage dependence of activation of IBa were found between tall and short hair cells. We conclude that both tall and short hair cells of the chick cochlea predominantly, if not exclusively, express noninactivating L-type calcium channels. These channels are therefore responsible for processes requiring voltage-dependent calcium entry through the basolateral cell membrane, such as transmitter release and activation of Ca(2+)-dependent K+ channels. PMID:7787021

Zidanic, M; Fuchs, P A

1995-01-01

186

Properties and uses of barium ferrite ceramic magnets  

Microsoft Academic Search

1.Barium ferrite is a promising ceramic material for permanent magnets. It does not include scarce and expensive materials. It has a low density and high coercive force; components with barium ferrite magnets therefore have high stability in operation, and high maximum specific magnetic energy, especially in anisotropic magnets.2.For the successful use of barium ferrite magnets it is essential to consider

I. Yu. Gershov

1963-01-01

187

Experiments with remote entanglement using single barium ions Nathan Kurz  

E-print Network

Experiments with remote entanglement using single barium ions Nathan Kurz A dissertation submitted entanglement using single barium ions Nathan Kurz Chair of the Supervisory Committee: Dr. Boris B. Blinov Physics Department Barium ion qubits are trapped and Doppler cooled in a linear Paul trap and the tasks

Blinov, Boris

188

Magnetoresistive Conductive Polyaniline-Barium Titanate Nanocomposites with Negative Permittivity  

E-print Network

Magnetoresistive Conductive Polyaniline-Barium Titanate Nanocomposites with Negative Permittivity field sensors,10 energy electrodes11 and biosensors.12,13 Barium titanate (BaTiO3) as transition metal Carolina 28301, United States ABSTRACT: Polyaniline (PANI) polymer nanocomposites (PNCs) filled with barium

Guo, John Zhanhu

189

Ferroelectric Properties of Individual Barium Titanate Nanowires Investigated  

E-print Network

Ferroelectric Properties of Individual Barium Titanate Nanowires Investigated by Scanned Probe on the ferroelectric properties of individual single-crystalline barium titanate nanowires. We show that nonvolatile report the scanned probe characterization of individual single-crystalline barium titanate (BaTiO3) nano

Heller, Eric

190

Compact pulse forming line using barium titanate ceramic material  

Microsoft Academic Search

Ceramic material has very high relative permittivity, so compact pulse forming line can be made using these materials. Barium titanate (BaTiO3) has a relative permittivity of 1200 so it is used for making compact pulse forming line (PFL). Barium titanate also has piezoelectric effects so it cracks during high voltages discharges due to stresses developed in it. Barium titanate is

Surender Kumar Sharma; P. Deb; R. Shukla; T. Prabaharan; A. Shyam

2011-01-01

191

Surface treatment of barium gallogermanate laser glass  

NASA Astrophysics Data System (ADS)

The surface of barium gallogermanate glass is modified through HCl solution etching to remove the surface defects and contaminations. The etching process and mechanism for barium gallogermanate glass in hydrochloric acid are investigated, and its optimum conditions are determined. However, the HCl etching induces the insoluble etch product containing minute crystal particles on glass surface. By heating BGG glass at the optical fiber drawing temperature, the deposited surface layer turned to be amorphous again and results in the increase of the transmittance of glass. The results indicated that the HCl etching combined with subsequent high-temperature heat treatment is an effective approach to improve the surface quality of barium gallogermanate glass, which would reduce the optical loss of the final optical fiber.

Yang, Gang; Qian, Qi; Yang, Zhongmin

2011-01-01

192

Molecular Structure of Calcium Monoxide  

NSDL National Science Digital Library

Calcium Oxide is a caustic white solid sparingly soluble in water; the commercial form is prepared by roasting calcium carbonate limestone in kilns until all the carbon dioxide is driven off. Calcium oxide is also known as burnt lime or caustic lime. This lime was used in glass production. Its ability to work with silicates is also used in modern metal production (steel, magnesium, aluminum, and other non-ferrous metals) industries to remove impurities as slag. It is also used in water and sewage treatment to reduce acidity; in agriculture to improve acid soils; and in pottery, concrete, paints and the food industry (pH adjuster for ice milk mix, dietary Supplements, dough conditioner, and yeast food).

2003-06-03

193

Hydrothermal Transformation of the Calcium Aluminum Oxide Hydrates CaAl2O4 . 10H2O and Ca2Al2O. 8H2O to Ca3Al2(OH)12 Investigated by In Situ Synchrotron X-ray Powder Diffraction  

SciTech Connect

The hydrothermal transformation of calcium aluminate hydrates were investigated by in situ synchrotron X-ray powder diffraction in the temperature range 25 to 170 C. This technique allowed the study of the detailed reaction mechanism and identification of intermediate phases. The material CaAl{sub 2}O{sub 4}{center_dot}10H{sub 2}O converted to Ca{sub 3}Al{sub 2}(OH){sub 12} and amorphous aluminum hydroxide. Ca{sub 2}Al{sub 2}O{sub 5}{center_dot}8H{sub 2}O transformed via the intermediate phase Ca{sub 4}Al{sub 2}O{sub 7}{center_dot}13H{sub 2}O to Ca{sub 3}Al{sub 2}(OH){sub 12} and gibbsite, Al(OH){sub 3}. The phase Ca{sub 4}Al{sub 2}O{sub 7}{center_dot}19H{sub 2}O reacted via the same intermediate phase to Ca{sub 3}Al{sub 2}(OH){sub 12} and mainly amorphous aluminum hydroxide. The powder pattern of the intermediate phase is reported.

Jensen,T.; Christensen, A.; Hanson, J.

2005-01-01

194

Intracytoplasmic barium salts in pleural fluid.  

PubMed

Cytological examination of the pleural effusion fluid obtained from a 66-yr-old Chinese lady showed numerous intra- and extracytoplasmic colourless refractile non-birefringent crystals. X-ray analysis of the crystals identified barium salts. On further inquiry, it was learnt that the fluid obtained had been placed in a specimen bottle provided by the x-ray department. This container was presumably contaminated with barium salts. The case highlights an unusual aspect of specimen contamination and the usefulness of x-ray analysis in the identification of crystals/substances. PMID:8165010

Chan, A C; Collins, R J; Cheung, T K

1993-10-01

195

Electric field tunable 60 GHz ferromagnetic resonance response in barium ferrite-barium strontium titanate multiferroic heterostructures  

E-print Network

barium strontium titanate films on Nb-doped strontium titanate substrates were capped with an unbondedElectric field tunable 60 GHz ferromagnetic resonance response in barium ferrite-barium strontium titanate multiferroic heterostructures Young-Yeal Song,1,a Jaydip Das,1 Pavol Krivosik,1,2 Nan Mo,1

Patton, Carl

196

Effect of powder synthesis procedure on calcium site occupancies in barium calcium titanate: A Rietveld analysis  

Microsoft Academic Search

(Ba,Ca)TiO3 samples with the ratio of (Ba+Ca) to Ti as unity but prepared by (i) a semiwet route involving (Ba,Ca)CO3 solid solution precursors and TiO2 and (ii) the conventional dry route involving BaCO3, CaCO3, and TiO2 powders, exhibit diffuse and BaTiO3-type sharp ferroelectric phase transitions, respectively. Rietveld analysis of neutron powder diffraction data from the two types of samples shows

P. S. R. Krishna; Dhananjai Pandey; V. S. Tiwari; R. Chakravarthy; B. A. Dasannacharya

1993-01-01

197

Long-term effects of calcium carbonate and 2.5 mEq\\/liter calcium dialysate on mineral metabolism  

Microsoft Academic Search

Long-term effects of calcium carbonate and 2.5 mEq\\/liter calcium dialysate on mineral metabolism. Many investigators have shown that calcium carbonate (CaCO3) is an effective phosphate binder which also prevents the potential disabling effects of aluminum (Al) accumulation. However, hypercalcemia may develop in a substantial numbers of patients. Thus, to control serum phosphate (PO4) and prevent hypercalcemia, we performed studies in

Eduardo Slatopolsky; Carol Weerts; Kathryn Norwood; Karla Giles; Patricia Fryer; Jane Finch; David Windus; James Delmez

1989-01-01

198

Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 are transparent materials with  

E-print Network

Barium Titanate and Bismuth Oxide Nanocomposites Barium titanate, BaTiO3, and bismuth oxide Bi2O3 Wall in Tetragonal Barium Titanate", H. Chaib, F. Schlaphof, T. Otto and L. M. Eng, Journal of Physics

Harmon, Julie P.

199

ARE THERE ANY STARS LACKING NEUTRON-CAPTURE ELEMENTS? EVIDENCE FROM STRONTIUM AND BARIUM  

SciTech Connect

The cosmic dispersion in the abundances of the heavy elements strontium and barium in halo stars is well known. Strontium and barium are detected in most cool, metal-poor giants, but are these elements always detectable? To identify stars that could be considered probable candidates for lacking these elements, I examine the stellar abundance data available in the literature for 1148 field stars and 226 stars in dwarf galaxies, 776 of which have metallicities lower than [Fe/H] <-2.0. Strontium or barium have been detected in all field, globular cluster, and dwarf galaxy environments studied. All upper limits are consistent with the lowest detected ratios of [Sr/H] and [Ba/H]. The frequent appearance of these elements raises the intriguing prospect that at least one kind of neutron-capture reaction operates as often as the nucleosynthesis mechanisms that produce lighter elements, such as magnesium, calcium, or iron, although the yields of heavy elements may be more variable.

Roederer, Ian U., E-mail: iur@obs.carnegiescience.edu [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2013-01-01

200

Electric Tuning of Ferromagnetic Resonances in Hexagonal-Barium-Ferrite\\/Barium-Strontium-Titanate Heterostructures  

Microsoft Academic Search

This letter reports the first demonstration of a monolithic heterostructure with a large electric tuning of the ferromagnetic resonance (FMR) at millimeter-wave frequencies. The structure is composed of a barium-strontium-titanate (BST) film and two thin platinum electrodes, all grown on a barium ferrite slab with in-plane uniaxial anisotropy. The electric tuning of the FMR responses around 60 GHz was obtained

Young-Yeal Song; Jaydip Das; Pavol Krivosik; Hyung-Kee Seo; Mingzhong Wu

2010-01-01

201

Investigations on barium ferrite magnetic thin films  

Microsoft Academic Search

Summary form only given. Barium ferrite thin films are promising candidates for both longitudinal and perpendicular recording media. It is important to understand the time dependent phenomena in these thin films as many of the critical properties of magnetic recording media are directly related to it. The time dependent phenomenon is also known as magnetic viscosity. The magnetic viscosity parameter,

Wenjie Pang; Hong Sun

2002-01-01

202

STABILIZED BARIUM TITANATE CERAMICS FOR CAPACITOR DIELECTRICS  

Microsoft Academic Search

The effects of additions of LaâOâ and LaâOâ--; 3TiOâ on the electronic properties of barium titanate were investigated. ; It was found that small additions of the components markedly increase the ; lifetime of the material subjected to d-c fields of 50 v per mil at 200 l ; C. (auth);

J. B. MacChesney; P. K. Gallagher; F. V. DiMarcello

1963-01-01

203

Phase associations of barium in marine sediments  

Microsoft Academic Search

Barium (Ba) is associated with various phases in marine sediments, including carbonates, organic matter, opal, ferromanganese oxyhydroxides, terrestrial silicates and other detrital material, and barite. Using samples representing sediments from a wide variety of sedimentary environments and export production regimes, we show that there is a considerable range in Ba concentrations associated with five operationally defined phases using a sequential

Meagan Eagle Gonneea; Adina Paytan

2006-01-01

204

Hydrolysis of aluminum dross material to achieve zero hazardous waste.  

PubMed

A simple method with high efficiency for generating high pure hydrogen by hydrolysis in tap water of highly activated aluminum dross is established. Aluminum dross is activated by mechanically milling to particles of about 45 ?m. This leads to removal of surface layer of the aluminum particles and creation of a fresh chemically active metal surface. In contact with water the hydrolysis reaction takes place and hydrogen is released. In this process a Zero Waste concept is achieved because the other product of reaction is aluminum oxide hydroxide (AlOOH), which is nature-friendly and can be used to make high quality refractory or calcium aluminate cement. For comparison we also used pure aluminum powder and alkaline tap water solution (NaOH, KOH) at a ratio similar to that of aluminum dross content. The rates of hydrogen generated in hydrolysis reaction of pure aluminum and aluminum dross have been found to be similar. As a result of the experimental setup, a hydrogen generator was designed and assembled. Hydrogen volume generated by hydrolysis reaction was measured. The experimental results obtained reveal that aluminum dross could be economically recycled by hydrolysis process with achieving zero hazardous aluminum dross waste and hydrogen generation. PMID:22326245

David, E; Kopac, J

2012-03-30

205

Studies of aluminum in rat brain  

SciTech Connect

The effects of high aluminum concentrations in rat brains were studied using /sup 14/C autoradiography to measure the uptake of /sup 14/C 2-deoxy-D-glucose (/sup 14/C-2DG) and microbeam proton-induced x-ray emission (microPIXE) with a 20-..mu..m resolution to measure concentrations of magnesium, aluminum, potassium, and calcium. The aluminum was introduced intracisternally in the form of aluminum tartrate (Al-T) while control animals were given sodium tartrate (Na-T). The /sup 14/C was administered intravenously. The animals receiving Al-T developed seizure disorders and had pathological changes that included cerebral cortical atrophy. The results showed that there was a decreased uptake of /sup 14/C-2DG in cortical regions in which increased aluminum levels were measured, i.e., there is a correlation between the aluminum in the rat brain and decreased brain glucose metabolism. A minimum detection limit of about 16 ppM (mass fraction) or 3 x 10/sup 9/ Al atoms was obtained for Al under the conditions employed. 14 refs., 4 figs., 1 tab.

Lipman, J.J.; Brill, A.B.; Som, P.; Jones, K.W.; Colowick, S.; Cholewa, M.

1985-01-01

206

Removal of Chloride from Wastewater by Advanced Softening Process Using Electrochemically Generated Aluminum Hydroxide  

E-print Network

solubility. Chloride can be removed from water and wastewater by precipitation as calcium chloroaluminate using advanced softening process. This research was conducted to evaluate chloride removal using electrochemically generated aluminum hydroxide and lime...

Mustafa, Syed Faisal

2014-07-23

207

Calcium orthophosphates  

PubMed Central

The present overview is intended to point the readers’ attention to the important subject of calcium orthophosphates. This type of materials is of special significance for human beings, because they represent the inorganic part of major normal (bones, teeth and antlers) and pathological (i.e., those appearing due to various diseases) calcified tissues of mammals. For example, atherosclerosis results in blood vessel blockage caused by a solid composite of cholesterol with calcium orthophosphates, while dental caries and osteoporosis mean a partial decalcification of teeth and bones, respectively, that results in replacement of a less soluble and harder biological apatite by more soluble and softer calcium hydrogenphosphates. Therefore, the processes of both normal and pathological calcifications are just an in vivo crystallization of calcium orthophosphates. Similarly, dental caries and osteoporosis might be considered an in vivo dissolution of calcium orthophosphates. Thus, calcium orthophosphates hold a great significance for humankind, and in this paper, an overview on the current knowledge on this subject is provided. PMID:23507744

Dorozhkin, Sergey V.

2011-01-01

208

Calcium Hydroxylapatite  

PubMed Central

Background: Calcium hydroxylapatite is one of the most well-studied dermal fillers worldwide and has been extensively used for the correction of moderate-to-severe facial lines and folds and to replenish lost volume. Objectives: To mark the milestone of 10 years of use in the aesthetic field, this review will consider the evolution of calcium hydroxylapatite in aesthetic medicine, provide a detailed injection protocol for a global facial approach, and examine how the unique properties of calcium hydroxylapatite provide it with an important place in today’s market. Methods: This article is an up-to-date review of calcium hydroxylapatite in aesthetic medicine along with procedures for its use, including a detailed injection protocol for a global facial approach by three expert injectors. Conclusion: Calcium hydroxylapatite is a very effective agent for many areas of facial soft tissue augmentation and is associated with a high and well-established safety profile. Calcium hydroxylapatite combines high elasticity and viscosity with an ability to induce long-term collagen formation making it an ideal agent for a global facial approach. PMID:25610523

Yutskovskaya, Yana Alexandrovna; Philip Werschler, WM.

2015-01-01

209

Microcapsules with Intrinsic Barium Radiopacity for Immunoprotection and X-ray/CT imaging of Pancreatic Islet Cells  

PubMed Central

Microencapsulation is a commonly used technique for immunoprotection of engrafted therapeutic cells. We investigated a library of capsule formulations to determine the most optimal formulation for pancreatic beta islet cell transplantation, using barium as the gelating ion and clinical-grade protamine sulfate (PS) as a new cationic capsule cross-linker. Barium-gelated alginate/PS/alginate microcapsules (APSA, diameter = 444±21 ?m) proved to be mechanically stronger and supported a higher cell viability as compared to conventional alginate/poly-L-lysine/alginate (APLLA) capsules. Human pancreatic islets encapsulated inside APSA capsules, gelated with 20 mM barium as optimal concentration, exhibited a sustained morphological integrity, viability, and functionality for at least 3–4 weeks in vitro, with secreted human C-peptide levels of 0.2–160 pg/ml/islet. Unlike APLLA capsules that are gelled with calcium, barium-APSA capsules are intrinsically radiopaque and, when engrafted into mice, could be readily imaged in vivo with micro-computed tomography (CT). Without the need of adding contrast agents, these capsules offer a clinically applicable alternative for simultaneous immunoprotection and real-time, non-invasive X-ray/CT monitoring of engrafted cells during and after in vivo administration. PMID:22444642

Arifin, D.R.; Manek, S.; Call, E.; Arepally, A.; Bulte, J.W.M.

2012-01-01

210

Physicochemical characteristics of Ba 2+ mixed calcium tartrate crystals  

Microsoft Academic Search

Non-linear optical single crystals of barium mixed calcium tartrate tetrahydrate with molecular formula Ca0.8Ba0.2C4H4O6·4H2O (CBT) have been grown in gels using a chemical reaction method at ambient temperature. The physical and chemical characteristics of gel grown CBT crystals have been investigated by employing Vickers micro hardness, etching, and thermal techniques. The single crystalline habit of CBT is deviated from that

K Suryanarayana; S. M Dharmaprakash

2002-01-01

211

Calcium-dependent inactivation of calcium channels in cochlear hair cells of the chicken.  

PubMed

Voltage-gated calcium channels support both spontaneous and sound-evoked neurotransmitter release from ribbon synapses of cochlear hair cells. A variety of regulatory mechanisms must cooperate to ensure the appropriate level of activity in the restricted pool of synaptic calcium channels ( approximately 100) available to each synaptic ribbon. One potential feedback mechanism, calcium-dependent inactivation (CDI) of voltage-gated, L-type calcium channels, can be modulated by calmodulin-like calcium-binding proteins. CDI of voltage-gated calcium current was studied in hair cells of the chicken's basilar papilla (analogous to the mammalian cochlea) after blocking the predominant potassium conductances. For inactivating currents produced by 2.5 s steps to the peak of the current-voltage relation (1 mm EGTA internal calcium buffer), single exponential fits yielded an average decay time constant of 1.92 +/- 0.18 s (mean +/- s.e.m., n = 12) at 20-22 degrees C, while recovery occurred with a half-time of approximately 10 s. Inactivation produced no change in reversal potential, arguing that the observed relaxation did not result from alternative processes such as calcium accumulation or activation of residual potassium currents. Substitution of external calcium with barium greatly reduced inactivation, while inhibition of endoplasmic calcium pumps with t-benzohydroquinone (BHQ) or thapsigargin made inactivation occur faster and to a greater extent. Raising external calcium 10-fold (from 2 to 20 mm) increased peak current 3-fold, but did not alter the extent or time course of CDI. However, increasing levels of internal calcium buffer consistently reduced the rate and extent of inactivation. With 1 mm EGTA buffering and in 2 mm external calcium, the available pool of calcium channels was half-inactivated near the resting membrane potential (-50 mV). CDI may be further regulated by calmodulin-like calcium-binding proteins (CaBPs). mRNAs for several CaBPs are expressed in chicken cochlear tissue, and antibodies to CaBP4 label hair cells, but not supporting cells, equivalent to the pattern seen in mammalian cochlea. Thus, molecular mechanisms that underlie CDI appeared to be conserved across vertebrate species, may provide a means to adjust calcium channel open probability, and could serve to maintain the set-point for spontaneous release from the ribbon synapse. PMID:17656437

Lee, Seunghwan; Briklin, Olga; Hiel, Hakim; Fuchs, Paul

2007-09-15

212

Calcium pyrophosphate arthritis (Pseudogout)  

MedlinePLUS

Calcium pyrophosphate dihydrate deposition disease; CPPD disease; Acute CPPD arthritis; Pseudogout ... Calcium pyrophosphate arthritis is caused by the collection of salt called calcium pyrophosphate dihydrate (CPPD). The buildup ...

213

Calcium carbonate overdose  

MedlinePLUS

Tums overdose; Calcium overdose ... Calcium ... Products containing calcium carbonate, including Certain antacids (Tums, Chooz) Certain mineral supplements Certain hand lotions Certain vitamin and mineral supplements Note: ...

214

Trapped Barium Ions for Quantum ComputationTrapped Barium Ions for Quantum Computation V.Mirgon, G.Shu, A.Avril, M.Dietrich N.Kurz, E. Shahar, and B.B.Blinov  

E-print Network

Trapped Barium Ions for Quantum ComputationTrapped Barium Ions for Quantum Computation V.Mirgon, G of Washington Seattle WA 98195 Trapped Barium Ions for Quantum ComputationTrapped Barium Ions for Quantum

Blinov, Boris

215

Ultrafast laser inscription of bistable and reversible waveguides in strontium barium niobate crystals  

E-print Network

Ultrafast laser inscription of bistable and reversible waveguides in strontium barium niobate optical channel waveguides in strontium barium niobate nonlinear ferroelectric crystals by direct barium niobate SBN crystal because of its prime importance in modern photonics due to its nonlinear

216

Enhanced dielectric properties from barium strontium titanate films with strontium titanate buffer layers  

E-print Network

Enhanced dielectric properties from barium strontium titanate films with strontium titanate buffer in their PE state. One of the leading material candidates for tunable materials is barium strontium titanate- tive amounts of Ba and Sr. TC for pure barium t

Alpay, S. Pamir

217

Engineering domain configurations for enhanced piezoelectricity in barium titanate single crystals  

E-print Network

Engineering domain configurations for enhanced piezoelectricity in barium titanate single crystals piezoelectric responses of barium titanate single crystals under different crystallographic orientations, and use it to explain the ultrahigh piezoelectric response recently observed in a 270 cut barium titanate

Li, Jiangyu

218

Band-Spectrum of Barium Oxide  

Microsoft Academic Search

THE introduction of barium salts to flames or arcs leads, in presence of oxygen, to the production of a characteristic band-spectrum attributed to BaO. Mecke and Guillery1 derived a band-head equation. Mahanti2 gave a new vibrational analysis and also made a rotational analysis. From this the spectrum was shown to arise from a 1Sigma - 1Sigma transition with B'e =

Albin Lagerqvist; Erland Lind; R. F. Barrow

1949-01-01

219

Mn2+, Ti4+ substituted barium ferrite  

Microsoft Academic Search

The substitution of iron by manganese in M-type barium ferrite BaFe12O19 has been investigated with the aim of elucidating its effect on the magnetic and magnetostrictive properties. Substitution of up to 0.4 manganese atoms per unit formula did not affect the magnetization whilst the anisotropy and magnetostriction decreased by 30% and 20%, respectively. Higher manganese contents gave rise to large

G. Turilli; F. Licci; S. Rinaldi; A. Deriu

1986-01-01

220

Barium ferrite films grown by laser ablation  

Microsoft Academic Search

Pulsed laser ablation (PLA) has been used to grow barium ferrite films on Al2O3 single crystal substrates. When deposition occurs in an oxidising atmosphere at high temperatures, the films are single BaFe12O19 phase, very well oriented with (001) texture, and exhibit a large perpendicular magnetic anisotropy. In this case, the microstructure and the anisotropy orientation are not influenced by variation

A. Lisfia; J. C. Lodder; P. de Haan; M. A. Smithers; F. J. G. Roesthuis

1998-01-01

221

New barium ferrite particles: Spherical shape  

Microsoft Academic Search

Pure and ZnTi-doped spherical barium ferrite particles were prepared using two different methods: semicoprecipitation and ultrasonic spray pyrolysis. The ultrasonic spray pyrolysis method was more effective in controlling particle shape. Particle size was in between 0.27 and 0.3 ?m. Coercivity and saturation magnetization were in the range of 1000 to 5000 Oe and 49 to 53 emu\\/g, respectively. Crystallization of

Y. K. Hong; H. S. Jung

1999-01-01

222

Barium ferrite thin-film recording media  

Microsoft Academic Search

Both longitudinal and perpendicular barium ferrite thin films are being pursued as overcoatless magnetic recording media. In this paper, prior research on thin-film Ba ferrite is reviewed and the most recent results are presented. Self-textured high-coercivity longitudinal Ba ferrite thin films have been achieved using conventional rf diode sputtering. Microstructural studies show that c-axis in-plane oriented grains have a characteristic

Xiaoyu Sui; Matthias Scherge; Mark H. Kryder; John E. Snyder; Vincent G. Harris; Norman C. Koon

1996-01-01

223

New barium ferrite particles: Spherical shape  

Microsoft Academic Search

Pure and ZnTi-doped spherical barium ferrite particles were prepared using two different methods: semicoprecipitation and ultrasonic spray pyrolysis. The ultrasonic spray pyrolysis method was more effective in controlling particle shape. Particle size was in between 0.27 and 0.3 mum. Coercivity and saturation magnetization were in the range of 1000 to 5000 Oe and 49 to 53 emu\\/g, respectively. Crystallization of

Y. K. Hong; H. S. Jung

1999-01-01

224

Production of translationally cold barium monohalide ions  

E-print Network

We have produced sympathetically cooled barium monohalide ions BaX$^+$ (X = F, Cl, Br) by reacting trapped, laser cooled Ba$^+$ ions with room temperature gas phase neutral halogen-containing molecules. Reaction rates for two of these (SF$_6$ and CH$_3$Cl) have been measured and are in agreement with classical models. BaX$^+$ ions are promising candidates for cooling to the rovibrational ground state, and our method presents a straightforward way to produce these polar molecular ions.

DePalatis, M V

2013-01-01

225

Analysis of 26 Barium Stars I. Abundances  

E-print Network

We present a detailed analysis of 26 barium stars, including dwarf barium stars, providing their atmospheric parameters (Teff, log g, [Fe/H], vt) and elemental abundances. We aim at deriving gravities and luminosity classes of the sample stars, in particular to confirm the existence of dwarf barium stars. Accurate abundances of chemical elements were derived. Abundance ratios between nucleosynthetic processes, by using Eu and Ba as representatives of the r- and s-processes are presented. High-resolution spectra with the FEROS spectrograph at the ESO-1.5m Telescope, and photometric data with Fotrap at the Zeiss telescope at the LNA were obtained. The atmospheric parameters were derived in an iterative way, with temperatures obtained from colour-temperature calibrations. The abundances were derived using spectrum synthesis for Li, Na, Al, alpha-, iron peak, s- and r-elements atomic lines, and C and N molecular lines. Atmospheric parameters in the range 4300 < Teff < 6500, -1.2 < [Fe/H] < 0.0 and 1.4 < log g < 4.6 were derived, confirming that our sample contains giants, subgiants and dwarfs. The abundance results obtained for Li, Al, Na, alpha- and iron peak elements for the sample stars show that they are compatible with the values found in the literature for normal disk stars in the same range of metallicities. Enhancements of C, N and heavy elements relative to Fe, that characterise barium stars, were derived and showed that [X/Ba] vs. [Ba/H] and [X/Ba] vs. [Fe/H] present different behaviour as compared to [X/Eu] vs. [Eu/H] and [X/Eu] vs. [Fe/H], reflecting the different nucleosynthetic sites for the s- and r-processes.

Dinah M. Allen; Beatriz Barbuy

2006-04-03

226

Improving the magnetic properties of hydrothermally synthesized barium ferrite  

Microsoft Academic Search

The formation of fine barium ferrite (BaFe12O19) powders under hydrothermal conditions at [OH?]\\/[NO3?] ratio of 2 has been examined by employing barium nitrate and ferric nitrate as the starting materials. The effects of Ba\\/Fe ratio, reaction temperature and time on the formation, particle size, and magnetic properties of barium ferrite were studied. To further enhance the magnetic properties of hydrothermally

Xiangyuan Liu; John Wang; Leong-Ming Gan; Ser-Choon Ng

1999-01-01

227

An investigation of particle size effects in ultrafine barium ferrite  

Microsoft Academic Search

Ultrafine particles of barium ferrite in the size range 5-100 nm have been synthesized by thermal decomposition of a citrate precursor. The precursor decomposed at 425°C is amorphous, but crystalline barium ferrite starts forming at temperatures of 550°C and above. Barium ferrite which shows a monophase X-ray diffraction pattern and well-resolved Mössbauer spectra is obtained at 700°C. The Mössbauer spectra

V. K. Sankaranarayanan; Q. A. Pankhurst; D. P. E. Dickson; C. E. Johnson

1993-01-01

228

Barium hexaferrite suspensions for electrophoretic deposition.  

PubMed

In this investigation we have looked at the preparation of barium hexaferrite suspensions, with the stability of the magnetic barium hexaferrite particles being increased by the addition of a surfactant, dodecylbenzylsulfonic acid (DBSA). The influence of the solubility DBSA in different solvents and its adsorption onto the surfaces of particles with different sizes were determined from zeta-potential measurements. The most suitable and stable suspensions of barium hexaferrite particles, regardless of their sizes, were obtained in 1-butanol, and these were then used for a subsequent electrophoretic deposition. The microstructures of the deposits were examined with electron microscopy. The thickness and density of the deposits as a function of the electric field, the zeta-potential, the particle size, and the separation distance between the electrodes were investigated. The thickness of the deposits was found to increase with the increasing zeta-potential of the suspension and with the increasing separation distance between the electrodes. Denser deposits were obtained from the suspensions of smaller particles that had narrower particle size distributions. PMID:19541323

Ovtar, Simona; Lisjak, Darja; Drofenik, Miha

2009-09-15

229

Creating unstable velocity-space distributions with barium injections  

NASA Technical Reports Server (NTRS)

Ion velocity-space distributions resulting from barium injections from orbiting spacecraft and shaped charges are discussed. Active experiments confirm that anomalous ionization processes may operate, but photoionization accounts for the production of the bulk of the barium ions. Pitch-angle diffusion and/or velocity-space diffusion may occur, but observations of barium ions moving upwards against gravity suggests that the ions retain a significant enough fraction of their initial perpendicular velocity to provide a mirror force. The barium ion plasmas should have a range of Alfven Mach numbers and plasma betas. Because the initial conditions can be predicted these active experiments should permit testing plasma instability hypotheses.

Pongratz, M. B.

1983-01-01

230

Aluminum-containing mesostructural materials  

Microsoft Academic Search

This article reviews syntheses of mesoporous aluminosilicates and aluminum oxides based on surfactant templating methods. The incorporation of aluminum in the silicate frameworks generates acid sites and ion-exchange sites. Both, tetrahedral framework aluminum and octahedral extraframework aluminum can be present, depending on the aluminum precursor used. The aluminum-containing structures tend to be less ordered than their purely siliccous analogs. Dealumination

Andreas Stein; Brian Holland

1996-01-01

231

Fabrication of Lotus-Type Porous Aluminum through Thermal Decomposition Method  

Microsoft Academic Search

Lotus-type porous aluminum with cylindrical pores was fabricated by unidirectional solidification through thermal decomposition of calcium hydroxide, sodium bicarbonate, or titanium hydride. The pore-forming gas decomposed from calcium hydroxide, sodium bicarbonate, and titanium hydride is identified as hydrogen. The elongated pores are evolved due to the solubility gap between liquid and solid when the melt dissolving hydrogen is solidified unidirectionally.

S. Y. Kim; J. S. Park; H. Nakajima

2009-01-01

232

Aluminum and Young Artists.  

ERIC Educational Resources Information Center

The author suggests a variety of ways in which aluminum and aluminum foil can be used in elementary and junior high art classes: relief drawing and rubbing; printing; repousse; sculpture; mobiles; foil sculpture; and three dimensional design. Sources of aluminum supplies are suggested. (SJL)

Anderson, Thomas

1980-01-01

233

Project Calcium  

SciTech Connect

Fouling problems in utility boilers have been classified into two principal types: high-temperature and low-temperature fouling. A multiclient-sponsored program was initiated at the Energy and Environmental Research Center (EERC) to better understand the causes of low-temperature fouling when burning high-calcium western US coals. The goals of Project Calcium were to define the low-temperature deposition problem, identify the calcium-based components that are responsible for the formation of the deposits, develop ways to predict their formation, and identify possible methods to mitigate the formation of these deposits. To achieve the goals of Project Calcium, detailed sampling of utility boilers and laboratory-scale studies coupled with state-of-the-art methods to determine the inorganic components in coals and coal ash-derived materials were conducted. Boiler Sampling was also performed. The work involved sampling coal, entrained ash, deposits and slags from five full-scale utility boilers combined with detailed advanced characterization of the materials. The results of this work aided in identifying the key phenomena to focus the laboratory studies and in model verification. Field testing was conducted at three utilities.

Hurley, J.P.; Benson, S.A.; Erickson, T.A.; Allan, S.E.; Bieber, J.

1992-09-01

234

Relationship of aluminum to Alzheimer's disease.  

PubMed Central

Alzheimer's disease is a progressive degenerative brain disease of unknown etiology, characterized by the development of large numbers of neurofibrillary tangles and senile plaques in the brain. Aluminum salts may be used experimentally to produce lesions which are similar, but not identical, to the neurofibrillary tangle. Although some studies have reported increased amounts of aluminum in the brains of Alzheimer's disease victims, these bulk analysis studies have been difficult to replicate and remain controversial. Using scanning electron microscopy with X-ray spectrometry, we have investigated this question on the cellular level. We have identified abnormal accumulations of aluminum within neurons derived from Alzheimer's disease patients containing neurofibrillary tangles. Similar accumulations have been detected in the numerous neurofibrillary tangle-bearing neurons seen in the brains of the indigenous native population of the island of Guam who suffer from amyotrophic lateral sclerosis and parkinsonism with dementia. Epidemiologic evidence strongly suggests a causal role for local environmental conditions relating to availability of aluminum, calcium, and magnesium. In view of the fact that a major consequence of acid rain is the liberation of large amounts of aluminum in bioavailable forms, concerns are raised about possible human health risks of this environmental phenomenon. PMID:4076080

Perl, D P

1985-01-01

235

Original article Availability of calcium from skim milk, calcium sulfate  

E-print Network

Original article Availability of calcium from skim milk, calcium sulfate and calcium carbonate; accepted 19 November 1999) Abstract --Dairy products provide abundant, accessible calcium for humans, while some calcium sulfate-rich mineral waters could provide appreciable amounts of calcium

Paris-Sud XI, Université de

236

Modifier cation (Ba, Ca, La, Y) field strength effects on aluminum and boron coordination in aluminoborosilicate glasses: the roles of fictive temperature and boron content  

NASA Astrophysics Data System (ADS)

The field strength of modifier cations has long been known to have important effects on oxide glass properties, but effects on network structure can be complex. For two series of barium, calcium, lanthanum and yttrium aluminoborosilicates with two different B/Si ratios, we report systematic variations in boron and aluminum coordination determined by NMR, and glass transition and heat capacities from differential scanning calorimetry. Data on glasses with different fictive temperatures allow B and Al speciation to be compared on an isothermal basis, rather than as conventionally done for as-quenched structures. Temperature and compositional effects can thus be isolated. These data and comparison to previous studies on glasses with lower B/Si ratios clearly show that higher modifier cation field strength increases the fraction of five- and six-coordinated Al in all compositions. In contrast, the previously documented trend towards more three-coordinated boron (and hence more non-bridging oxygens, NBO) in low B/Si glasses with higher field strength cations reverses in high B/Si and in high NBO compositions. Al and B coordination numbers both decrease with higher fictive temperature in the glasses studied here, suggesting a simple mechanism of coupled structural change.

Morin, Elizabeth I.; Wu, Jingshi; Stebbins, Jonathan F.

2014-08-01

237

Calcium and bone disease  

PubMed Central

Calcium transport and calcium signaling are of basic importance in bone cells. Bone is the major store of calcium and a key regulatory organ for calcium homeostasis. Bone, in major part, responds to calcium-dependent signals from the parathyroids and via vitamin D metabolites, although bone retains direct response to extracellular calcium if parathyroid regulation is lost. Improved understanding of calcium transporters and calcium-regulated cellular processes has resulted from analysis of genetic defects, including several defects with low or high bone mass. Osteoblasts deposit calcium by mechanisms including phosphate and calcium transport with alkalinization to absorb acid created by mineral deposition; cartilage calcium mineralization occurs by passive diffusion and phosphate production. Calcium mobilization by osteoclasts is mediated by acid secretion. Both bone forming and bone resorbing cells use calcium signals as regulators of differentiation and activity. This has been studied in more detail in osteoclasts, where both osteoclast differentiation and motility are regulated by calcium. PMID:21674636

Blair, Harry C.; Robinson, Lisa J.; Huang, Christopher L.-H.; Sun, Li; Friedman, Peter A.; Schlesinger, Paul H.; Zaidi, Mone

2013-01-01

238

BARIUM IN TEETH AS INDICATOR OF BODY BURDEN  

EPA Science Inventory

A study was conducted to determine the biological availability of naturally occurring barium in a municipal drinking water by the analysis of barium in deciduous teeth of children. The grade school children of two Illinois towns were chosen for the study. The towns were chosen ba...

239

Laser Cooled Single Ion Spectroscopy of Magnesium and Barium  

Microsoft Academic Search

Individual ions of magnesium and barium have been isolated and confined in RF traps in an ultra high vacuum environment. The ion motion has been cooled by means of a resonant laser excitation. The single ions were detected by their laser induced fluorescence. The kinetic temperature of magnesium was measured to be less than 200 millidegrees Kelvin. In barium, a

Gary Robert Janik

1984-01-01

240

The application of barium ferrite particles in advanced recording media  

Microsoft Academic Search

Barium ferrite is a leading candidate material for advanced magnetic recording media. Tapes and disks made with it offer output amplitudes at recording densities of current interest (75-100 kfci) that far exceed those of advanced acicular oxides and are comparable to those of many commercially available media made with metallic particles (MP). The very high coercivity values available with barium

M. P. Sharrock; L. W. Carlson

1995-01-01

241

M-Type Barium Hexagonal Ferrite Films Mingzhong Wu  

E-print Network

-type barium hexagonal ferrite BaFe12O19 (BaM) films as a replacement for those magnetic garnets. BaM films can2 M-Type Barium Hexagonal Ferrite Films Mingzhong Wu Department of Physics, Colorado State University, Fort Collins, USA 1. Introduction Magnetic garnet materials such as yttrium iron garnet (YIG

242

Recording performance of longitudinal barium ferrite thin film media  

Microsoft Academic Search

The high density recording characteristics of barium ferrite thin film media have been investigated. High levels of overwrite are achieved. Media microstructures have been identified to have a close relation to the noise behavior in the barium ferrite thin films. A linear increase in noise spectra is observed, indicating the existence of transition noise. In addition, positive ?M peaks are

Xiaoyu Sui; A. Singh; Yinglian Chen; D. N. Lambeth; M. K. Krydeer

1995-01-01

243

Thermal decomposition of (BaTi) citrates into barium titanate  

Microsoft Academic Search

From aqueous solutions of barium and titanium citrates two different (BaTi) citrate salts can be precipitated, depending on the pH of the solution. The ratio of barium to titanium in the salts is either 1 : 1 or 2 : 1. The thermal decomposition of the salts was investigated by means of DTA, TGA, infrared spectroscopy, and X-ray diffraction. At

D. Hennings; W. Mayr

1978-01-01

244

Explanation of the apparent sublinear photoconductivity of photorefractive barium titanate  

Microsoft Academic Search

We explain the apparent sublinear intensity dependence of photoconductivity in barium titanate. In our model shallow acceptors act as a reservoir for charges optically excited from the donors. As this reservoir fills, the fraction of occupied donors changes appreciably, changing the lifetime of the free carriers. We identify two types of barium titanate crystals having quite different photorefractive characteristics, depending

Daniel Mahgerefteh; Jack Feinberg

1990-01-01

245

Barium strontium titanate powder obtained by polymeric precursor method  

SciTech Connect

Pure barium strontium titanate powder, with Ba/Sr ratio of 80/20 was prepared by the polymeric precursor method (also called Pechini process). The powder was obtained after a calcination at 800 deg. C for 8 h and characterized by XRD, IR, BET and SEM. The requirements to avoid barium carbonate as a secondary phase are presented and discussed in detail.

Ries, A.; Simoes, A.Z.; Cilense, M.; Zaghete, M.A.; Varela, J.A

2003-03-15

246

Barium Enhancement in NGC 6819 Blue Stragglers  

NASA Astrophysics Data System (ADS)

Possible formation pathways for blue straggler stars include mergers in hierarchical triple systems, stellar collisions during dynamical encounters, and mass transfer from a giant companion. Extensive work on the blue stragglers in the old open cluster NGC 188 (7 Gyr) has led to exciting discoveries including a binary secondary mass distribution peaked at 0.5 MSolar and the detection of three young white dwarf binary companions. These indicate that mass transfer from an asymptotic giant branch star is the dominant mechanism for blue straggler formation in open clusters. Such mass transfer events should pollute the surface abundance of the blue straggler with nucleosynthesis products from the evolved donor. The other formation pathways, mergers and collisions, are predicted to produce no such enhancements. In an effort to move beyond NGC 188 and into other open clusters we present the first results of a surface abundance study of the blue stragglers in the intermediate-aged open cluster NGC 6819 (2.5 Gyr) using the Hydra multi-object spectrograph on the WIYN 3.5 m telescope. This part of our study centers on the s-process element barium as a tracer of formation via mass transfer. We compare the blue straggler surface abundance of barium to that of a sample of main-sequence stars in NGC 6819 and find multiple blue stragglers with anomalous abundances. Surprising, most of the blue stragglers with barium anomalies show no radial-velocity evidence for a companion. We gratefully acknowledge funding from the National Science Foundation under grant AST- 0908082 and the Wisconsin Space Grant Consortium.

Milliman, Katelyn; Mathieu, Robert D.; Schuler, Simon C.

2015-01-01

247

Proper Management for Morbid Iatrogenic Retroperitoneal Barium Insufflation  

PubMed Central

A barium enema is a diagnostic and therapeutic procedure commonly used for colon and rectum problems. Rectal perforation with extensive intra- and/or extraperitoneal spillage of barium is a devastating complication of a barium enema that leads to a significant increase in patient mortality. Due to the low number of reported cases in recent scientific literature and the lack of experience with the management of these cases, we would like to present our treatment approach to a rare case of retroperitoneal contamination with barium, followed by its intraperitoneal involvement during a diagnostic barium enema. Our experience with long-term management of the patient and the good outcome will be depicted in this paper. PMID:25580416

Vahedian-Ardakani, Jalal; Nazerani, Shahram; Saraee, Amir; Sarmast, Ali; Saraee, Ehsan

2014-01-01

248

Europium-doped barium bromide iodide  

SciTech Connect

Single crystals of Ba0.96Eu0.04BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl2 structure [Braekken (1932). Z. Kristallogr. 83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = +-0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic arrangement.

Gundiah, Gautam; Hanrahan, Stephen M.; Hollander, Fredrick J.; Bourret-Courchesne, Edith D.

2009-10-21

249

Europium-doped barium bromide iodide.  

PubMed

Single crystals of Ba(0.96)Eu(0.04)BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl(2) structure [Braekken (1932 ?). Z. Kristallogr.83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = ±0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic arrangement. PMID:21578035

Gundiah, Gautam; Hanrahan, Stephen M; Hollander, Frederick J; Bourret-Courchesne, Edith D

2009-01-01

250

Short-cavity squeezing in barium  

NASA Technical Reports Server (NTRS)

Broadband phase sensitive noise and squeezing were experimentally observed in a system of barium atoms interacting with a single mode of a short optical cavity. Squeezing of 13 +/- 3 percent was observed. A maximum possible squeezing of 45 +/- 8 percent could be inferred for out experimental conditions, after correction for measured loss factors. Noise reductions below the quantum limit were found over a range of detection frequencies 60-170 MHz and were best for high cavity transmission and large optical depths. The amount of squeezing observed is consistent with theoretical predictions from a full quantum statistical model of the system.

Hope, D. M.; Bachor, H-A.; Manson, P. J.; Mcclelland, D. E.

1992-01-01

251

Dielectric properties of barium titanate supramolecular nanocomposites.  

PubMed

Nanostructured dielectric composites can be obtained by dispersing high permittivity fillers, barium titanate (BTO) nanocubes, within a supramolecular framework. Thin films of BTO supramolecular nanocomposites exhibit a dielectric permittivity (?r) as high as 15 and a relatively low dielectric loss of ?0.1 at 1 kHz. These results demonstrate a new route to control the dispersion of high permittivity fillers toward high permittivity dielectric nanocomposites with low loss. Furthermore, the present study shows that the size distribution of nanofillers plays a key role in their spatial distribution and local ordering and alignment within supramolecular nanostructures. PMID:24584569

Lee, Keun Hyung; Kao, Joseph; Parizi, Saman Salemizadeh; Caruntu, Gabriel; Xu, Ting

2014-04-01

252

B To Identify Slag-Affected Sediment in Southern  

E-print Network

of slag in northwestern Indiana, is approximately 95% silicates and aluminosilicates of calcium solids, suspended solids, total organic carbon, calcium, potassium, sodium, chloride, aluminum, barium shown that slag-affected water precipitates carbonate and sulfate minerals and dissolves native silicate

253

Randomized crossover study comparing the phosphate-binding efficacy of calcium ketoglutarate versus calcium carbonate in patients on chronic hemodialysis.  

PubMed

The objective of the study was to evaluate the phosphate-binding efficacy, side effects, and cost of therapy of calcium ketoglutarate granulate as compared with calcium carbonate tablets in patients on chronic hemodialysis. The study design used was a randomized, crossover open trial, and the main outcome measurements were plasma ionized calcium levels, plasma phosphate levels, plasma intact parathyroid hormone (PTH) levels, requirements for supplemental aluminum-aminoacetate therapy, patient tolerance, and cost of therapy. Nineteen patients on chronic hemodialysis were treated with a dialysate calcium concentration of 1.25 mmol/L and a fixed alfacalcidol dose for at least 2 months. All had previously tolerated therapy with calcium carbonate. Of the 19 patients included, 10 completed both treatment arms. After 12 weeks of therapy, the mean (+/-SEM) plasma ionized calcium level was significantly lower in the ketoglutarate arm compared with the calcium carbonate arm (4.8+/-0.1 mg/dL v 5.2+/-0.1 mg/dL; P = 0.004), whereas the mean plasma phosphate (4.5+/-0.3 mg/dL v 5.1+/-0.1 mg/dL) and PTH levels (266+/-125 pg/mL v 301+/-148 pg/mL) did not differ significantly between the two treatment arms. Supplemental aluminum-aminoacetate was not required during calcium ketoglutarate treatment, while two patients needed this supplement when treated with calcium carbonate. Five of 17 (29%) patients were withdrawn from calcium ketoglutarate therapy within 1 to 2 weeks due to intolerance (anorexia, vomiting, diarrhea, general uneasiness), whereas the remaining 12 patients did not experience any side effects at all. The five patients with calcium ketoglutarate intolerance all had pre-existing gastrointestinal symptoms; four of them had received treatment with cimetidine or omeprazol before inclusion into the study. Calculations based on median doses after 12 weeks showed that the cost of the therapy in Denmark was 10 times higher for calcium ketoglutarate compared with calcium carbonate (US$6.00/d v US$0.65/d). Calcium ketoglutarate may be an effective and safe alternative to treatment with aluminum-containing phosphate binders in patients on hemodialysis who are intolerant of calcium carbonate or acetate because of hypercalcemia. However, care must be exercised when dealing with patients with pre-existing gastrointestinal discomfort. Due to the high cost of the therapy, calcium ketoglutarate should be used only for selected patients. PMID:9469496

Bro, S; Rasmussen, R A; Handberg, J; Olgaard, K; Feldt-Rasmussen, B

1998-02-01

254

Calcium and Vitamin D  

Technology Transfer Automated Retrieval System (TEKTRAN)

Calcium is required for the bone formation phase of bone remodeling. Typically about 5 nmol (200 mg) of calcium is removed from the adult skeleton and replaced each day. To supply this amount, one would need to consume about 600 mg of calcium, since calcium is not very efficiently absorbed. Calcium ...

255

Calcium and osteoporosis  

Microsoft Academic Search

Calcium is an essential nutrient that is involved in most metabolic processes and the phosphate salts of which provide mechanical rigidity to the bones and teeth, where 99% of the body's calcium resides. The calcium in the skeleton has the additional role of acting as a reserve supply of calcium to meet the body's metabolic needs in states of calcium

B. E. Christopher Nordin

1997-01-01

256

Barium ferrite powders prepared by microwave-induced hydrothermal reaction and magnetic property  

Microsoft Academic Search

We have prepared barium ferrite particles by the microwave-induced hydrothermal method. The crystallization of the barium ferrite particles is promoted within a short time by microwave irradiation because the seeds of barium ferrite having large permeability are rapidly heated through the interaction of barium ferrite with the magnetic component of the microwaves. Crystals having unusually low thickness were obtained compared

Tomohisa Yamauchi; Yasunori Tsukahara; Takao Sakata; Hirotaro Mori; Tsukasa Chikata; Shunsaku Katoh; Yuji Wada

2009-01-01

257

Earthquake-induced barium anomalies in the Lisan Formation, Dead Sea Rift valley, Israel  

E-print Network

Earthquake-induced barium anomalies in the Lisan Formation, Dead Sea Rift valley, Israel Amitai Editor: L. Stixrude Keywords: barium Dead Sea seismite earthquake Lisan recurrence rate Prominent barium The present paper is a rst report of prominent barium concen- tration anomalies in seismically perturbed

Marco, Shmuel "Shmulik"

258

Fluid seepage along the San Clemente Fault scarp: basin-wide impact on barium cycling  

E-print Network

Fluid seepage along the San Clemente Fault scarp: basin-wide impact on barium cycling Marta E present evidence that the barium released at cold seeps along the San Clemente Fault zone may significantly impact the geochemical budget of barium within the basin. Barium fluxes at seep localities

Huh, Chih-An

259

Aspects of aluminum toxicity  

SciTech Connect

Aluminum is the most abundant metal in the earth's crust. The widespread occurrence of aluminum, both in the environment and in foodstuffs, makes it virtually impossible for man to avoid exposure to this metal ion. Attention was first drawn to the potential role of aluminum as a toxic metal over 50 years ago, but was dismissed as a toxic agent as recently as 15 years ago. The accumulation of aluminum, in some patients with chronic renal failure, is associated with the development of toxic phenomena; dialysis encephalopathy, osteomalacic dialysis osteodystrophy, and an anemia. Aluminum accumulation also occurs in patients who are not on dialysis, predominantly infants and children with immature or impaired renal function. Aluminum has also been implicated as a toxic agent in the etiology of Alzheimer's disease, Guamiam amyotrophic lateral sclerosis, and parkinsonism-dementia. 119 references.

Hewitt, C.D.; Savory, J.; Wills, M.R. (Univ. of Virginia Health Sciences Center, Charlottesville (USA))

1990-06-01

260

Aluminum powder metallurgy processing  

SciTech Connect

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.

Flumerfelt, J.F.

1999-02-12

261

Improved cryogenic aluminum mirrors  

Microsoft Academic Search

Optical surface deformation of metal mirrors used at cryogenic temperatures is reduced through the use of a new process of plating amorphous aluminum on aluminum. The AlumiPlateTM process (produced by AlumiPlate, Inc. in Minneapolis, MN) plates a layer of 99.9+% high purity aluminum about 125 micrometers thick atop the substrate. Very good surface finishes are produced by direct diamond turning

Daniel Vukobratovich; Ken Don; Richard E. Sumner

1998-01-01

262

Releasing effects in flame photometry: Determination of calcium  

USGS Publications Warehouse

Strontium, lanthanum, neodymium, samarium, and yttrium completely release the flame emission of calcium from the depressive effects of sulfate, phosphate, and aluminate. Magnesium, beryllium, barium, and scandium release most of the calcium emission. These cations, when present in high concentration, preferentially form compounds with the depressing anions when the solution is evaporated rapidly in the flame. The mechanism of the interference and releasing effects is explained on the basis of the chemical equilibria in the evaporating droplets of solution and is shown to depend upon the nature of the compounds present in the aqueous phase of the solution. The need for background correction techniques is stressed. The releasing effect is used in the determination of calcium in silicate rocks without the need for separations.

Dinnin, J.I.

1960-01-01

263

Calcium Collage  

NSDL National Science Digital Library

In this activity (on pages 11-14 of PDF), learners cut out pictures from magazines of foods that help make bones strong and glue the pictures to a paper bone. The lesson plan includes information about various activities - including physical exercise as well as diet - that lead to healthy bones. It also includes a list of foods that provide calcium to strengthen bones, including dairy products, spinach, and tofu. The paper bones can be cut out of construction paper prior to the activity.

OMSI

2004-01-01

264

The flame photometric determination of calcium in phosphate, carbonate, and silicate rocks  

USGS Publications Warehouse

A flame photometric method of determining calcium in phosphate, carbonate, and silicate locks has been developed Aluminum and phosphate interference was overcome by the addition of a large excess of magnesium. The method is rapid and suitable for routine analysis Results obtained are within ?? 2% of the calcium oxide content. ?? 1957.

Kramer, H.

1957-01-01

265

Characterization of calcium oxalate defective (cod) 3 mutant from Medicago truncatula  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many plants invest a considerable amount of resources and energy into the formation of calcium oxalate crystals. Assigned roles for plant crystal formation include functions in defense, calcium regulation, and aluminum tolerance. From a human health standpoint, oxalate present in edible plant tiss...

266

Effect of B-site europium doping on the hydrogen transport properties of barium cerate  

NASA Astrophysics Data System (ADS)

Barium cerate doped with europium on the Ce-site (B-site of the ABO3 perovskite structure) has been investigated as a potential material for hydrogen separation. Barium cerate doped with 15 mol% europium (BaCe0.85Eu0.15O3-delta) demonstrated higher electrical conductivity in a hydrogen-containing gas stream than gadolinium-doped barium cerate (BaCe0.85Gd0.15O3-delta), which was known to have one of the highest conductivities (0.027 S/cm 2 compared to 0.021 S/cm2 at 800°C). For europium dopant levels between 5 to 25 mol%, the sample doped with 15 mol% demonstrated higher electrical conductivities in dry forming gas (4% H2/96% N2) dry air, and wet nitrogen. The activation energies in dry air (˜0.60 eV) were indicative of p-type electronic conduction, and the activation energies in hydrogen-containing gases (˜0.35--0.45 eV) were indicative of protonic conduction. With BaCe0.85Eu0.15O3-delta , the onset of n-type electronic conductivity necessary for hydrogen separation was shown to occur at ˜600°C. A gas-tight glass seal was developed to study the hydrogen permeation properties of BaCe0.85Eu0.15O3-delta. The glass seal was a composite of a glass containing strontium oxide, boron oxide, silicon oxide, aluminum oxide, and lanthanum oxide mixed with doped barium cerate powder. The seal would form at temperatures >875°C, allowing for testing down to 650°C. The effect of temperature, feed-side hydrogen partial pressure, and membrane thickness on hydrogen permeation flux of BaCe0.85Eu0.15O 3-delta was investigated. For the range of thicknesses studied (0.75 to 2.00 mm), the performance of BaCe0.85Eu0.15O 3-delta membranes is under mixed control of bulk diffusion and surface kinetics. This mixed control indicates that investigating BaCe 0.85Eu0.15O3-delta membranes thinner than 0.75 mm would result in a limited increase in hydrogen permeation flux unless measures were taken to improve surface kinetics. The need for improved surface kinetics was confirmed when surface modification using porous platinum on a 1.00 mm membrane resulted in an increase in permeation flux.

Rhodes, James Michael

267

Calcium hydroxide poisoning  

MedlinePLUS

Calcium hydroxide is a white powder produced by mixing calcium oxide ("lime") with water. Calcium hydroxide poisoning ... Blood in the stool Burns in the esophagus (food pipe) Severe abdominal pain Vomiting Vomiting blood Heart ...

268

Calcium source (image)  

MedlinePLUS

Getting enough calcium to keep bones from thinning throughout a person's life may be made more difficult if that person has ... as a tendency toward kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also effects the ...

269

Coronary Calcium Scan  

MedlinePLUS

... the NHLBI on Twitter. What Is a Coronary Calcium Scan? A coronary calcium scan is a test ... you have calcifications in your coronary arteries. Coronary Calcium Scan Figure A shows the position of the ...

270

Calcium and bones (image)  

MedlinePLUS

Calcium is one of the most important minerals for the growth, maintenance, and reproduction of the human ... body, are continually being re-formed and incorporate calcium into their structure. Calcium is essential for the ...

271

Get Enough Calcium  

MedlinePLUS

... Physical Activity > Nutrition > Get Enough Calcium Get Enough Calcium The Basics Take Action! Ver en español Content ... February 24, 2015 The Basics Your body needs calcium to build strong bones when you are young ...

272

Calcium-Rich Foods  

MedlinePLUS

... Disorders - Osteoporosis - Prevention - Calcium - Calcium content of common foods Printer friendly Email Share Tweet Like Below is ... Green/French beans 90 g cooked 50 Starchy foods Food Serving Size Calcium (mg) Pasta (cooked) 180 ...

273

Hygienic importance of increased barium content in some fresh waters.  

PubMed

In surface waters of the mining and processing areas of uranium ore there is an increased content of free and bound barium ions due to the use of barium salts for the treatment of waste and mine waters containing radium. In model experiments with the algae Ankistrodesmus falcatus, Chlorella kessleri and Scenedesmus obliquus, we studied the effect of Ba2+ on the accumulation of 226Ra. It was found that the accumulation of radium by algae is negatively influenced with barium concentrations higher than 1 mg.l-1. The accumulation of barium of organisms of primary production was studied using 133BaCl2. At a barium content in the medium of 4.0, 0.46 and 0.04 mu. l-1, the algae accumulated 30-60% of the added amount of barium during an exposure of 15 days. Biochemical analyses showed that barium is bound to the cellular membrane and to other components of the algal cell that cannot be extracted with water or alcohol. PMID:7462608

Havlík, B; Hanusová, J; Rálková, J

1980-01-01

274

Do all barium stars have a white dwarf companion?  

NASA Technical Reports Server (NTRS)

International Ultraviolet Explorer short-wavelength, low-dispersion spectra were analyzed for four barium, two mild barium, and one R-type carbon star in order to test the hypothesis that the barium and related giants are produced by mass transfer from a companion now present as a white dwarf. An earlier tentative identification of a white dwarf companion to the mild barium star Zeta Cyg is confirmed. For the other stars, no ultraviolet excess attributable to a white dwarf is seen. Limits are set on the bolometric magnitude and age of a possible white dwarf companion. Since the barium stars do not have obvious progenitors among main-sequence and subgiant stars, mass transfer must be presumed to occur when the mass-gaining star is already on the giant branch. This restriction, and the white dwarf's minimum age, which is greater than 8 x 10 to the 8th yr, determined for several stars, effectively eliminates the hypothesis that mass transfer from an asymptotic giant branch star creates a barium star. Speculations are presented on alternative methods of producing a barium star in a binary system.

Dominy, J. F.; Lambert, D. L.

1983-01-01

275

Carbothermic Aluminum Production Using Scrap Aluminum As A Coolant  

DOEpatents

A process for producing aluminum metal by carbothermic reduction of alumina ore. Alumina ore is heated in the presence of carbon at an elevated temperature to produce an aluminum metal body contaminated with about 10-30% by wt. aluminum carbide. Aluminum metal or aluminum alloy scrap then is added to bring the temperature to about 900-1000.degree. C. and precipitate out aluminum carbide. The precipitated aluminum carbide is filtered, decanted, or fluxed with salt to form a molten body having reduced aluminum carbide content.

LaCamera, Alfred F. (Trafford, PA)

2002-11-05

276

Infrared Study of Superconductivity: Grating Coupled Plasmons in Yttrium BARIUM(2) COPPER(3) OXYGEN(7) and Gap Features in BARIUM(1-X) Potassium(x) Bismuth OXYGEN(3)  

NASA Astrophysics Data System (ADS)

The electrodynamic properties of two different superconductors, Barium Potassium Bismuth Oxide (BKBO) and Yttrium Barium Copper Oxide (YBCO) have been studied using the technique of transmission Fourier transform spectroscopy with liquid helium temperature bolometric detection. Plasmon resonances have been observed in far infrared transmission measurements on superconducting YBCO films. An Aluminum/Nichrome grating is used to couple infrared radiation to collective two-dimensional plasma modes. The plasmon dispersion is measured by using different grating periods. The strength of the plasma resonances weaken, then disappear as the temperature approaches the critical temperature. The results are analyzed using a grating coupler theory that includes the hybridization of the plasmons with the diffraction modes. Data taken in a magnetic field of up to 12 Tesla are characteristic of the real part of the conductivity of the YBCO film increasing with field, behavior similar to that with increasing of temperature. These results are consistent with the inducement of vortices in the YBCO film. The far infrared transmission of BKBO thin films, grown on Magnesium Oxide (MgO) substrates, was measured in the frequency range from 15 to 200 wavenumbers, and temperature range from 9 to 100 Kelvin. There is a BCS -like peak in the transmission spectrum. The strong coupling Eliashberg theory gives a better description of the optical data than the weak coupling Mattis-Bardeen theory. For an 18 Kelvin critical temperature (T_{c }) sample the Eliashberg model extrapolated to zero temperature gives a London penetration depth of 5500+/-100A and an energy gap of 6.2 meV (50.1 wavenumbers, or 4.0 kT_{c }). Because BKBO is in the dirty limit, the strong coupling characteristics in the optical conductivity is adequately described by the Allen-Dynes parameter only, as opposed to the full Holstein structure due to the electron -phonon interaction alpha^2F(omega). .

Dunmore, Franklin John

1995-01-01

277

Microstructure and magnetism in barium strontium titanate (BSTO)-barium hexaferrite (BaM) multilayers  

SciTech Connect

High quality multilayers of barium ferrite (BaM) and barium strontium titanate (BSTO) were grown in optimized conditions on thermally oxidized Si(1 0 0) and Al{sub 2}O{sub 3} substrates using magnetron sputtering. As-grown films were amorphous and different annealing procedures were explored to stabilize crystalline phases. BSTO and BaM phases were identified using X-ray diffraction and cross-sectional scanning electron micrographs showed sharp interfaces between BSTO and BaM layers. Magnetic hysteresis loops obtained at various temperatures and field orientations showed a large coercivity ({approx}2500 Oe) consistent with the hard magnetic hexaferrite component. Hysteresis loops also revealed the distinct influence of magnetocrystalline and shape anisotropies at different temperature ranges.

Frey, N.A. [Materials Physics Laboratory, Physics Department, University of South Florida, 4202 East Fowler Avenue, Tampa, FL 33620 (United States); Heindl, R. [Materials Physics Laboratory, Physics Department, University of South Florida, 4202 East Fowler Avenue, Tampa, FL 33620 (United States); Srinath, S. [Materials Physics Laboratory, Physics Department, University of South Florida, 4202 East Fowler Avenue, Tampa, FL 33620 (United States); Srikanth, H. [Materials Physics Laboratory, Physics Department, University of South Florida, 4202 East Fowler Avenue, Tampa, FL 33620 (United States)]. E-mail: sharihar@cas.usf.edu; Dudney, N.J. [Solid State Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2005-08-11

278

Adsorption of radium and barium on goethite and ferrihydrite: A kinetic and surface complexation modelling study  

NASA Astrophysics Data System (ADS)

Radium and barium uptake onto ferrihydrite and goethite have been studied in the concentration range 1 nM to 5 mM and from pH 4 to 10, to develop a model to predict radium behaviour in legacy uranium mining wastes. For ferrihydrite, uptake of Ra2+ at nM concentrations was strong at pH >7. At higher concentrations, Ba2+ sorption to ferrihydrite was slightly weaker than that of Ra2+. Experiments with goethite showed weaker binding for both metal ions in all systems. The interactions of radium with both ferrihydrite and goethite are fully reversible. The behaviour of radium during transformation of ferrihydrite to goethite has been studied, and no evidence for irreversible incorporation within the goethite lattice was found; radium uptake to goethite was the same, whether or not it was present during its formation. Calcium competed with radium for ferrihydrite sorption only at high calcium concentrations (>10 mM). Barium is a more effective competitor, and a concentration of 1 mM reduced radium sorption. Sediment samples from a legacy uranium mining site have been analysed, and the in situ Rd values are consistent with radium uptake by surface coatings of ferrihydrite or goethite like phases. Surface complexation models have been developed for radium sorption to ferrihydrite and goethite which simulate the experimental data successfully. In both cases, approaches based on a single surface functional group and tetradentate binding sites simulated the data successfully. These data could be used in underpinning the safety case for legacy mining sites.

Sajih, M.; Bryan, N. D.; Livens, F. R.; Vaughan, D. J.; Descostes, M.; Phrommavanh, V.; Nos, J.; Morris, K.

2014-12-01

279

Migration and redistribution of oxygen vacancy in barium titanate ceramics  

SciTech Connect

Degradation of barium titanate based multilayer capacitor mainly results from migration and redistribution of oxygen vacancy. For barium titanate ceramics, the authors observe an internal friction relaxation peak around 70 deg. C due to oxygen vacancy, and its relaxation strength differs greatly for specimen aged at 85 deg. C for 120 h and at 150 deg. C for 5 h. Two possible explanations are proposed, one based on symmetry-conforming short-range order while the other on the interaction between oxygen vacancy and domain wall during aging process. In any case, relaxation thermodynamics is a powerful tool to investigate the migration and redistribution of oxygen vacancy in barium titanate ceramics.

Chen, L.; Xiong, X. M.; Meng, H.; Lv, P.; Zhang, J. X. [State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)

2006-08-14

280

Transient Inclusion Evolution During Modification of Alumina Inclusions by Calcium in Liquid Steel: Part II. Results and Discussion  

NASA Astrophysics Data System (ADS)

The formation of intermediate reaction products after calcium addition to aluminum-killed steel was studied. Steel samples were taken from laboratory and industrial heats before and at various times after calcium treatment. Inclusions were characterized by automated and manual scanning electron microscopy and X-ray microanalysis of polished cross sections and inclusions extracted by dissolution of the steel. Industrial and laboratory melts containing more than 40 parts per million (by mass) of dissolved sulfur showed calcium sulfide as the main reaction product after calcium injection, with calcium aluminates appearing later. It is proposed that the calcium aluminates are formed by reaction between the calcium sulfide and the alumina. A laboratory heat containing 7 parts per million of sulfur showed calcium oxide as the main initial calcium reaction product. A simple mechanism is proposed for the modification of alumina inclusions by calcium, considering transient CaO and CaS formation.

Verma, N.; Pistorius, Petrus C.; Fruehan, Richard J.; Potter, Michael; Lind, Minna; Story, Scott R.

2011-08-01

281

Designed microstructures in textured barium hexaferrite  

NASA Astrophysics Data System (ADS)

It is a fundamental principle of materials science that the microstructure of a material defines its properties and ultimately its performance for a given application. A prime example of this can be found in the large conch shell Strombus gigas, which has an intricate microstructure extending across five distinct length scales. This microstructure gives extraordinary damage tolerance to the shell. The structure of Strombus gigas cannot be replicated in a modern engineering ceramic with any existing processing technique, so new processing techniques must be developed to apply this structure to a model material. Barium hexaferrite was chosen as a model material to create microstructures reminiscent of Strombus gigas and evaluate its structure-property relations. This work describes novel processing methods to produce textured barium hexaferrite with no coupling between the sample geometry and the texture direction. This technique, combining magnetic field-assisted gelcasting with templated grain growth, also allows multilayer samples to be fabricated with different texture directions in adjacent layers. The effects of adding either B2O3 or excess BaCO 3 on the densification and grain growth of barium hexaferrite was studied. The texture produced using this technique was assessed using orientation imaging microscopy (OIM) at Oak Ridge National Laboratory. These measurements showed peak textures as high as 60 MRD and sharp interfaces between layers cast with different texture directions. The effect of oxygen on the quality of gelcasting is also discussed, and it is shown that with proper mold design, it is possible to gelcast multiple layers with differing texture directions without delamination. Monolithic and multilayer samples were produced and tested in four point bending to measure the strength and work of fracture. Modulus measurements, made with the ultrasonic pulse-echo technique, show clear signs of microcracking in both the isotropic and textured samples. Both the strength and work of fracture were shown to be affected by the texture direction. The multilayer samples did not show significant improvements in either strength or work of fracture, but they did show much less variability than the monolithic samples.

Hovis, David Brian

282

Influence of addition of rare earth metals to aluminum on the effectiveness of absorption of impurity oxygen from argon in a closed system  

SciTech Connect

Removal of oxygen from closed systems plays a significant part in increasing the life of devices operating in absence of oxygen and other harmful impurities (e.g., in incandescent lamps, electronic tubes, etc.). Harmful gases are removed with the aid of gas absorbents. Magnesium, barium, aluminum, zirconium, titanium, rare earth metals (r.e.m.), and their compounds are used as gas absorbents. However, because of their high activity these substances are generally unsuitable for use in electric lamp production. Some of them, such as barium and magnesium, form deposits in the bulb dome which lower the luminous flux of the lamp, while others, e.g., zirconium, aluminum, and r.e.m., lose their initial activity during the technological assembly operations. In this communication results are reported of an investigation of the influence of rare earth metals added to aluminum on oxygen absorption in a closed space (incandescent lamp) when the oxygen content in the main gas is very low.

Glavatskii, Y.F.; Kozik, V.V.; Leshchev, S.V.; Serebrennikov, V.V.

1983-07-10

283

Aluminum alumina joining  

NASA Astrophysics Data System (ADS)

Aluminum tensile adhesion to alumina composites containing varying volume fractions of borosilicate glass was examined. Alumina composites were found to bond to aluminum at a reaction temperature of 800 C with tensile bond strengths of 62 MPa, observed for composites containing 15 percent glass.

Haber, R. A.; Greenhut, Victor A.

284

Anodizing Aluminum with Frills.  

ERIC Educational Resources Information Center

"Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are also…

Doeltz, Anne E.; And Others

1983-01-01

285

Aluminum Carbothermic Technology  

Microsoft Academic Search

This report documents the non-proprietary research and development conducted on the Aluminum Carbothermic Technology (ACT) project from contract inception on July 01, 2000 to termination on December 31, 2004. The objectives of the program were to demonstrate the technical and economic feasibility of a new carbothermic process for producing commercial grade aluminum, designated as the ''Advanced Reactor Process'' (ARP). The

Marshall J

2005-01-01

286

Hydrothermal transformation of the calcium aluminum oxide hydrates CaAl{sub 2}O{sub 4}.10H{sub 2}O and Ca{sub 2}Al{sub 2}O{sub 5}.8H{sub 2}O to Ca{sub 3}Al{sub 2}(OH){sub 12} investigated by in situ synchrotron X-ray powder diffraction  

SciTech Connect

The hydrothermal transformation of calcium aluminate hydrates were investigated by in situ synchrotron X-ray powder diffraction in the temperature range 25 to 170 deg. C. This technique allowed the study of the detailed reaction mechanism and identification of intermediate phases. The material CaAl{sub 2}O{sub 4}.10H{sub 2}O converted to Ca{sub 3}Al{sub 2}(OH){sub 12} and amorphous aluminum hydroxide. Ca{sub 2}Al{sub 2}O{sub 5}.8H{sub 2}O transformed via the intermediate phase Ca{sub 4}Al{sub 2}O{sub 7}.13H{sub 2}O to Ca{sub 3}Al{sub 2}(OH){sub 12} and gibbsite, Al(OH){sub 3}. The phase Ca{sub 4}Al{sub 2}O{sub 7}.19H{sub 2}O reacted via the same intermediate phase to Ca{sub 3}Al{sub 2}(OH){sub 12} and mainly amorphous aluminum hydroxide. The powder pattern of the intermediate phase is reported.

Jensen, Torben R. [Interdisciplinary Nanoscience Center, Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000 Aarhus C (Denmark)]. E-mail: trj@chem.au.dk; Christensen, Axel Norlund [Hojkolvej 7, DK-8210 Arhus V (Denmark); Hanson, Jonathan C. [Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973, USA (United States)

2005-12-15

287

Magnetic properties of substituted barium ferrite powders  

SciTech Connect

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.

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

1994-03-01

288

Theoretical isotope shifts in neutral barium  

E-print Network

The present work deals with a set of problems in isotope shifts of neutral barium spectral lines. Some well known transitions ($6s^2~^1S_0-6s6p~^{1,3}P^o_1$ and $6s^2~^1S_0-6p^2~^3P_0$) are first investigated. Values of the changes in the nuclear mean-square charge radius are deduced from the available experimental isotope shifts using our ab initio electronic factors. The three sets $\\{ \\delta\\langle r^2\\rangle^{A,A'}\\} $ obtained from these lines are consistent with each other. The combination of the available nuclear mean-square radii with our electronic factors for the $6s5d~^3D_{1,2} -6s6p~^{1}P^o_1$ transitions produces isotope shift values in conflict with the laser spectroscopy measurements of Dammalapati et al. (Eur. Phys. J. D 53, 1 (2009)).

Nazé, Cédric; Godefroid, Michel

2015-01-01

289

The Aluminum Smelting Process  

PubMed Central

This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development. PMID:24806722

2014-01-01

290

Aluminum structural applications  

SciTech Connect

Extensive research by aluminum producers and automakers in the 1980s resulted in the development of technologies that enable building of aluminum cars that meet and exceed all the expectations of today`s drivers and passengers, yet weigh several hundred pounds less than their steel counterparts. The Acura NSX sports car, the Audi A8, and the Jaguar XJ220 have all been introduced. Ford has built 40 aluminum-intensive automobiles based on the Taurus/Sable for test purposes, and General Motors recently announced an aluminum-structured electric vehicle. The design flexibility that aluminum allows is shown by these examples. Each uses a somewhat different technology that is particularly suited to the vehicle and its market.

Lucas, G. [Alcan Rolled Products Co., Farmington Hills, MI (United States)

1996-05-01

291

The aluminum smelting process.  

PubMed

This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development. PMID:24806722

Kvande, Halvor

2014-05-01

292

Phased surgical treatment of barium enema-induced rectal injury and retention of barium in the pelvic floor space  

PubMed Central

Iatrogenic injuries caused by barium enema are rarely reported. Following a phased surgical protocol for up to one year, we have successfully treated a patient with rectal injury and severe infection of the pelvic floor space complicated with retention of large amounts of barium and vaginal fistula. In this article, the phased surgery planning for the treatment of rectal injury complicated with vaginal fistula is discussed in terms of the pros and cons, and the observed effect and evolution of barium retained in the pelvic floor space are described. PMID:25405155

Yang, Xuefei; Xia, Ligang; Huang, Jun; Wang, Jianping

2014-01-01

293

A triangular heterometallic siloxide containing barium  

SciTech Connect

Reaction of KOSiPh[sub 3] with Ba[sub 3](OSiPh[sub 3])[sub 6](THF) in THF displaces barium from the triangular reagent to yield a colorless solid. Recrystallization in the presence of MeOC[sub 2]H[sub 4]OMe(DME) yields KBa[sub 2](OSiPh[sub 3])[sub 5](DME)[sub 2], characterized by [sup 1]H and [sup 29]Si NMR spectroscopy and X-ray diffraction. The molecule contains a triangular KBa[sub 2]([mu][sub 3]-OSiPh[sub 3])[sub 2]([mu][sub 2]-OSiPh[sub 3])[sub 3] core with [eta][sup 1] and [eta][sup 2]-DME ligation on each barium. The benzene-soluble molecule is fluxional in solution at both the OSiPh[sub 3] and the DME groups. At -70C in CH[sub 2]Cl[sub 2]/C[sub 6]D[sub 6], both [eta][sup 1]-DME/[eta][sup 2]-DME site exchange and intramolecular siloxide migration have been slowed, and the spectra are in agreement with retention of the solid-state structure in solution. Crystallographic data for KBa[sub 2](OSiPh[sub 3])[sub 5](DME)[sub 2] (-159C): a = 15.474 (3) [angstrom], b = 26.466 (6) [angstrom], c = 23.783 (5) [angstrom], [beta] = 99.80 (1)[degree] with Z = 4 in space group P2[sub 1]/n.

Coan, P.S.; Streib, W.E.; Caulton, K.G. (Indiana Univ., Bloomington (United States))

1991-12-25

294

Upper gastrointestinal barium evaluation of duodenal pathology: A pictorial review.  

PubMed

Like other parts of the gastrointestinal tract (GIT), duodenum is subject to a variety of lesions both congenital and acquired. However, unlike other parts of the GIT viz. esophagus, rest of the small intestine and large intestine, barium evaluation of duodenal lesions is technically more challenging and hence not frequently reported. With significant advances in computed tomography technology, a thorough evaluation including intraluminal, mural and extramural is feasible in a single non-invasive examination. Notwithstanding, barium evaluation still remains the initial and sometimes the only imaging study in several parts of the world. Hence, a thorough acquaintance with the morphology of various duodenal lesions on upper gastrointestinal barium examination is essential in guiding further evaluation. We reviewed our experience with various common and uncommon barium findings in duodenal abnormalities. PMID:25170399

Gupta, Pankaj; Debi, Uma; Sinha, Saroj Kant; Prasad, Kaushal Kishor

2014-08-28

295

Improved dielectric strength of barium titanate-polyvinylidene fluoride nanocomposite  

NASA Astrophysics Data System (ADS)

Barium titanate-polyvinydene fluoride nanocomposites with improved dielectric strength were prepared, in which on the surface of the barium titanate nanoparticle was coated. The results showed that the dielectric breakdown strength of the nanocomposites increase significantly up to 250 kV/mm and then decrease. Microstructural investigations revealed that the coated barium titanate nanoparticles were well-dispersed in polyvinydene fluoride. Fourier transform infrared spectroscopy confirmed that there is a large coverage of cross-linking in both interfaces of the barium titanate-titanate and the titanate-polyvinydene fluoride, which can connect the composites to form an organically integrated body, which result in the increase of the dielectric strength of the nanocomposites.

Dou, Xiaoliang; Liu, Xiaolin; Zhang, Yong; Feng, Huan; Chen, Jian-Feng; Du, Song

2009-09-01

296

Liquid-phase-deposited barium titanate thin films on silicon  

NASA Astrophysics Data System (ADS)

Using a mixture of hexafluorotitanic acid, barium nitrate and boric acid, high refractive index (1.54) barium titanate films can be deposited on silicon substrates. The deposited barium titanate films have featureless surfaces. The deposition temperature is near room temperature (80°C). However, there are many fluorine and silicon incorporations in the films. The refractive index of the as-deposited film is 1.54. By current-voltage measurement, the leakage current of the as-deposited film with a thickness of 1000 Å is about 9.48×10-7 A cm-2 at the electrical field intensity of 0.3 MV cm-1. By capacitance-voltage measurement, the effective oxide charge of the liquid-phase-deposited barium titanate film is 3.06×1011 cm-2 and the static dielectric constant is about 22.

Lee, Ming-Kwei; Liao, Hsin-Chih; Tung, Kuan-Wen; Shih, Chung-Min; Shih, Tsung-Hsiang

2002-01-01

297

Calculated emission rates for barium releases in space  

NASA Technical Reports Server (NTRS)

The optical emissions from barium releases in space are caused by resonance and fluorescent scattering of sunlight. Emission rates for the dominant ion and neutral lines are calculated assuming the release to be optically thin and the barium to be in radiative equilibrium with the solar radiation. The solar spectrum has deep Fraunhofer absorption lines at the primary barium ion resonances. A velocity component toward or away from the sun will Doppler shift the emission lines relative to the absorption lines and the emission rates will increase many-fold over the rest value. The Doppler brightening is important in shaped charge or satellite releases where the barium is injected at high velocities. Emission rates as a function of velocity are calculated for the 4554, 4934, 5854, 6142 and 6497 A ion emission lines and the dominant neutral line at 5535 A. Results are presented for injection parallel to the ambient magnetic field, B, and for injection at an angle to B.

Stenbaek-Nielsen, H. C.

1989-01-01

298

Upper gastrointestinal barium evaluation of duodenal pathology: A pictorial review  

PubMed Central

Like other parts of the gastrointestinal tract (GIT), duodenum is subject to a variety of lesions both congenital and acquired. However, unlike other parts of the GIT viz. esophagus, rest of the small intestine and large intestine, barium evaluation of duodenal lesions is technically more challenging and hence not frequently reported. With significant advances in computed tomography technology, a thorough evaluation including intraluminal, mural and extramural is feasible in a single non-invasive examination. Notwithstanding, barium evaluation still remains the initial and sometimes the only imaging study in several parts of the world. Hence, a thorough acquaintance with the morphology of various duodenal lesions on upper gastrointestinal barium examination is essential in guiding further evaluation. We reviewed our experience with various common and uncommon barium findings in duodenal abnormalities. PMID:25170399

Gupta, Pankaj; Debi, Uma; Sinha, Saroj Kant; Prasad, Kaushal Kishor

2014-01-01

299

Study of the photovoltaic effect in thin film barium titanate  

NASA Technical Reports Server (NTRS)

The feasibility of making non-volatile digital memory devices of barium titanate, BaTiO3, that are integrated onto a silicon substrate with the required ferroelectric film produced by processing, compatible with silicon technology was examined.

Grannemann, W. W.; Dharmadhikari, V. S.

1983-01-01

300

Synthesis, photoluminescence and magnetic properties of barium vanadate nanoflowers  

SciTech Connect

Graphical abstract: The flower-shaped barium vanadate was obtained for the first time. The photoluminescence and magnetic properties of the barium vanadate nanoflowers were investigated at room temperature. Research highlights: {yields} In the paper, the flower-shaped barium vanadate were obtained for the first time. The CHM method used here is new and simple for preparation of barium vanadate. {yields} The photoluminescence and magnetic properties of the barium vanadate nanoflowers were investigated at room temperature. The strong bluish-green emission was observed. {yields} The ferromagnetic behavior of the barium vanadate nanoflowers was found with saturation magnetization of about 83.50 x 10{sup -3} emu/g, coercivity of 18.89 Oe and remnant magnetization of 4.63 x 10{sup -3} emu/g. {yields} The mechanisms of PL and magnetic property of barium vanadate nanoflowers have been discussed. -- Abstract: The flower-shaped barium vanadate has been obtained by the composite hydroxide mediated (CHM) method from V{sub 2}O{sub 5} and BaCl{sub 2} at 200 {sup o}C for 13 h. XRD and XPS spectrum of the as-synthesized sample indicate it is hexagonal Ba{sub 3}V{sub 2}O{sub 8} with small amount of Ba{sub 3}VO{sub 4.8} coexistence. Scan electron microscope and transmission electron microscope display that the flower-shaped crystals are composed of nanosheets with thickness of {approx}20 nm. The UV-visible spectrum shows that the barium vanadate sample has two optical gaps (3.85 eV and 3.12 eV). Photoluminescence spectrum of the barium vanadate flowers exhibits a visible light emission centered at 492 and 525 nm which might be attributed to VO{sub 4} tetrahedron with T{sub d} symmetry in Ba{sub 3}V{sub 2}O{sub 8}. The ferromagnetic behavior of the barium vanadate nanoflowers has been found with saturation magnetization of about 83.50 x 10{sup -3} emu/g, coercivity of 18.89 Oe and remnant magnetization of 4.63 x 10{sup -3} emu/g, which is mainly due to the presence of a non-orthovanadate phase with spin S = 1/2.

Xu, Jing [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China) [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China); Chongqing University of Science and Technology, Chongqing 401331 (China); Hu, Chenguo, E-mail: hucg@cqu.edu.cn [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China)] [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China); Xi, Yi [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China)] [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China); Peng, Chen [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China)] [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Wan, Buyong; He, Xiaoshan [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China)] [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China)

2011-06-15

301

A search for technetium (Tc II) in barium stars  

NASA Technical Reports Server (NTRS)

The authors searched without success for the lines of Tc II at 2647.02, 2610.00 and 2543.24 A in IUE spectra of the barium stars HR 5058, Omicron Vir, and Zeta Cap. The lack of Tc II implies that the observed s-process enhancements were produced more than half a million years ago and supports the suggestion that the spectral peculiarities of barium stars are probably related to the binary nature of the stars.

Little-Marenin, Irene R.; Little, Stephen J.

1987-01-01

302

Kinetics and mechanisms of hydrothermal synthesis of barium titanate  

Microsoft Academic Search

Reaction mechanisms for the hydrothermal synthesis of barium titanate are evaluated. Feedstocks of barium hydroxide octahydrate and anatase titania are reacted for varying durations (1--72 h) to provide intermediate-stage samples for characterization by transmission electron microscopy\\/energy-dispersive spectroscopy (TEM\\/EDS), X-ray diffractometry (XRD), and inductively coupled plasma spectroscopy (ICP) and XRD methods permits the analysis of data with the Johnson-Mehl-Avrami equation. This

James O. Eckert; Catherine C. Hung-Houston; Bonnie L. Gersten; Malgorzata M. Lencka; Richard E. Riman

1996-01-01

303

On the nature of defects in barium ferrite platelets  

Microsoft Academic Search

Barium ferrite (Ba.0.6Fe2O3) platelets of approximatelyfrac{1}{2}mum diameter and with intrinsic coercive force of about 5000 Oe were crystallized from a glass phase. To study the nature of the defects and their influence on the magnetic properties, the crystailized glass was plastically deformed by applying a pressure of 30 kbar in an opposed anvil press. Barium ferrite platelets were extracted from

D. Ratnam; W. Buessem

1970-01-01

304

'Skidding' of the CRRES G-9 barium release  

NASA Technical Reports Server (NTRS)

A simulation study and experimental data of the CRRES G-9 ionospheric barium release are presented. The simulation study is based on a 2D electrostatic code that incorporates time-dependent coupling to the background plasma. It is shown that the densest portion of the barium ion cloud 'skids' about 15 km within the first three seconds following the release, consistent with the optical data analyses.

Huba, J. D.; Mitchell, H. G.; Fedder, J. A.; Bernhardt, P. A.

1992-01-01

305

Thermal Decomposition of Barium Dioxodiaquaperoxyoxalato Uranate(VI) Hydrate  

Microsoft Academic Search

Barium dioxodiaquaperoxyoxalatouranate was obtained by reaction of uranyl nitrate with oxalic acid and then hydrogen peroxide\\u000a in the presence of barium ion. The complex was subjected to chemical analysis. The thermal decomposition behaviour of the\\u000a complex was studied using TG, DTG and DTA techniques. The solid complex salt and the intermediate product of its thermal decomposition\\u000a were characterized using IR

B. B. V. Sailaja; T. Kebede; M. S. Prasada Rao

2002-01-01

306

Neutron source, neutron density and the origin of barium stars  

Microsoft Academic Search

The authors present new high resolution spectra of the MgH profiles in nine barium stars, and determine, by spectral synthesis techniques, the magnesium isotopic ratios in each star. When compared with recent AGB nucleosynthesis calculations, they can emphatically rule out the operation of the 22Ne(alpha, n)25Mg reaction as the neutron source responsible for the s-process enhancements observed in these barium

Robert A. Malaney; David L. Lambert

1988-01-01

307

Aluminum monocarbonyl and aluminum isocarbonyl Steve S. Wesolowski,a)  

E-print Network

Aluminum monocarbonyl and aluminum isocarbonyl Steve S. Wesolowski,a) T. Daniel Crawford,b) Justin of the aluminum monocarbonyl species AlCO and AlOC have been performed to predict the geometries, fragmentation, Ogden, and Oswald6 first isolated aluminum dicarbonyls in solid krypton and identified the species

Crawford, T. Daniel

308

Aluminum: Reducing chloride emissions from aluminum production  

Microsoft Academic Search

Reynolds Metals Company (RMC), with assistance from a NICE³ grant, is developing for commercialization a closed-loop control process that greatly reduces chlorine emissions and increases plant efficiency while maintaining metal quality. The process still utilizes chlorine to remove impurities during aluminum processing, but is more effective than current methods. With the new technology chlorine in the stack is monitored and

Simon

1999-01-01

309

Fatal barium chloride poisoning: four cases report and literature review.  

PubMed

Barium is an alkaline earth metal which has a variety of uses including in the manufacturing industry and in medicine. However, adverse health effects and fatalities occur due to absorption of soluble barium compounds, notably the chloride, nitrate, and hydroxide, which are toxic to humans. Although rare, accidental and suicidal modes of poisoning are sporadically reported in the literature.We describe 4 cases of poisoning due to barium chloride in China. In witnessed cases, severe gastrointestinal symptoms, hypokalemia leading to muscle weakness, cardiac arrhythmias, and respiratory failure were noted. Autopsy showed some nonspecific but common findings, such as subendocardial hemorrhage in the ventricles, visceral petechiae, and fatty changes in the liver. Interestingly, microscopic examination showed degenerative changes and amorphous, flocculent foamy materials in the renal tubules. Toxicology was relevant for barium in blood and tissues. Three of the cases were accidental and 1 homicidal in nature. A round-up of relevant literature on fatal barium compounds poisoning is also provided. Forensic pathologists should be aware of the clinical presentations of barium compound poisoning and especially look for any evidence of hypokalemia. Still, postmortem toxicological and histological studies are essential for an accurate identification of the cause of death. PMID:23629399

Ananda, Sunnassee; Shaohua, Zhu; Liang, Liu

2013-06-01

310

Clinical biochemistry of aluminum  

SciTech Connect

Aluminum toxicity has been implicated in the pathogenesis of a number of clinical disorders in patients with chronic renal failure on long-term intermittent hemodialysis treatment. The predominant disorders have been those involving either bone (osteomalacic dialysis osteodystrophy) or brain (dialysis encephalopathy). In nonuremic patients, an increased brain aluminum concentration has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease and was associated with experimental neurofibrillary degeneration in animals. The brain aluminum concentrations of patients dying with the syndrome of dialysis encephalopathy (dialysis dementia) are significantly higher than in dialyzed patients without the syndrome and in nondialyzed patients. Two potential sources for the increased tissue content of aluminum in patients on hemodialysis have been proposed: (1) intestinal absorption from aluminum containing phosphate-binding gels, and (2) transfer across the dialysis membrane from aluminum in the water used to prepare the dialysate. These findings, coupled with our everyday exposure to the ubiquitous occurrence of aluminum in nature, have created concerns over the potential toxicity of this metal.

King, S.W.; Savory, J.; Wills, M.R.

1981-05-01

311

Update on Calcium Signaling Calcium Signaling through Protein Kinases. The  

E-print Network

Update on Calcium Signaling Calcium Signaling through Protein Kinases. The Arabidopsis Calcium protein kinase activities occur through calcium-dependent protein kinases (CDPKs). These novel calcium provides a valuable opportunity to understand the plant calcium-signaling network. Calcium is a ubiquitous

Sheen, Jen

312

Aequorin response facilitation and intracellular calcium accumulation in molluscan neurones  

PubMed Central

1. When molluscan neural somata are filled with the calcium-indicating photo-protein aequorin and subjected to a 1 Hz train of depolarizing pulses (0·3 sec duration to + 15 mV) under voltage clamp, the successive photo-emissions due to calcium influx facilitate. The origin of this phenomenon was investigated in identified neurones from the abdominal ganglion of Aplysia californica. 2. Since outward currents inactivate cumulatively in successive pulses, the effective depolarization increases due to a series resistance error. Elimination of this error by electronic compensation or pharmacological block of outward current reduced aequorin response facilitation by only about 30%, on the average. 3. When voltage-dependent sodium and potassium currents are blocked in tetraethylammonium (TEA)-substituted zero-sodium sea water, the remaining inward calcium currents display no facilitation. On the contrary, a slow decline during a pulse and a slight progressive depression in successive pulses are observed. Barium-substitution for calcium in the same medium eliminates a small residual potassium current insensitive to external TEA. The remaining inward barium currents also display depression instead of facilitation. 4. A non-pharmacological separation of calcium current was accomplished by measuring tail currents at the potassium equilibrium potential following depolarizing pulses. Calcium tail currents activate rapidly and then decline gradually and incompletely as depolarizing pulse duration is lengthened. Tail currents also show no evidence of facilitation; there is instead a slight depression of currents after successive pulses. 5. Increments of optical absorbance in neurones filled with the calcium-sensitive dye arsenazo III show a depression rather than facilitation to successive depolarizations in a train. The time course of these absorbance signals is consistent with the time-dependent depression of calcium current. 6. Calibration of arsenazo III response amplitude indicates that the dye reports only about 1% of the calcium concentration increment expected from knowledge of cell volume and the charge carried by calcium current during a depolarizing pulse. This suggests that cytoplasmic buffering of free calcium must occur rapidly, on a time scale comparable to the response time of arsenazo III (about 1 msec) or more rapidly. 7. The slow potassium tail current following a depolarizing pulse is calcium-dependent and probably provides an approximate index of the internal sub-membrane calcium concentration. Increments in this current after repetitive pulses display a slight progressive depression rather than facilitation. 8. Since neither calcium currents nor the concentration transients show facilitation, we conclude that aequorin response facilitation is due to the non-linear dependence of aequorin photo-emissions on calcium concentration. This conclusion is supported by a finding that the very different kinetics of arsenazo III responses and aequorin responses can be reconciled by a simple model representing calcium accumulation and known response properties of the two indicator substances. 9. In a train of impulses evoked by injecting depolarizing current into a neurone, the successive action potentials grow in duration. Nevertheless, a nearly constant calcium influx signalled by arsenazo III accompanies broadening action potentials. PMID:6247486

Smith, Stephen J.; Zucker, Robert S.

1980-01-01

313

Calcium Depletion in Forest Soils of the Eastern US  

NSDL National Science Digital Library

This week's In the News focuses on calcium depletion in the forest soils of ten states in the Eastern US. Calcium depletion decreases the ability of trees to "ward off stresses such as temperature changes and insect defoliation". Scientists have noted that sugar maples and red spruce trees in ten different sites now have reduced resistance to "defoliation by insects and low winter temperatures". In a recent report, scientists Gregory Lawrence and Thomas Huntington of the US Geological Survey (USGS) claim that a cause of calcium depletion is acid rain. Lawrence and Huntington describe a mechanism whereby acid rain decreases calcium soil content: ". . . sulfuric and nitric acids from acid deposition . . . tend to remain in solution within the mineral soil where they lower the pH, thereby releasing aluminum to soil water and causing the leaching of calcium". In addition, timber harvesting may also contribute to the depletion of calcium in forest soils because, as trees are removed from the site, the calcium within them is removed as well. Due to the combined effects of acid rain and timber harvest, some areas have low calcium soil content and consequently low forest growth. The nine resources listed provide background information on acid rain and articles and research efforts on the relationship between calcium soil content and acid rain.

Nannapaneni, Sujani.

314

Purifying Aluminum by Vacuum Distillation  

NASA Technical Reports Server (NTRS)

Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

Du Fresne, E. R.

1985-01-01

315

Advances in aluminum anodizing  

NASA Technical Reports Server (NTRS)

White anodize is applied to aluminum alloy surfaces by specific surface preparation, anodizing, pigmentation, and sealing techniques. The development techniques resulted in alloys, which are used in space vehicles, with good reflectance values and excellent corrosive resistance.

Dale, K. H.

1969-01-01

316

Corrosion Inhibitors for Aluminum.  

ERIC Educational Resources Information Center

Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

Muller, Bodo

1995-01-01

317

Synthesis of single-crystal barium titanium isopropoxide complex to form barium titanate  

SciTech Connect

Single-crystal barium titanate double alkoxide complex with a composition presumed to be BaTi(OCH(CH[sub 3])[sub 2])[sub 6][center dot]xC[sub 6]H[sub 6] was successfully synthesized in this work. The crystal was converted to BaTiO[sub 3] at 100 C. The preparation of the oxides via single crystals of metal alkoxides has some advantage over the well-known sol-gel method in that it results in oxides with well-defined and homogeneous compositions at the atomic level and in fine particle sizes, smaller than 50 nm.

Suyama, Yoko (Japan Fine Ceramic Center, Nagoya (Japan)); Nagasawa, Mitsuru (Toyota Technological Inst., Nagoya (Japan))

1994-02-01

318

Determination of micro amounts of iron, aluminum, and alkaline earth metals in silicon carbide  

NASA Technical Reports Server (NTRS)

A colorimetric method for analysis of micro components in silicon carbide used as the raw material for varistors is described. The microcomponents analyzed included iron soluble in hydrochloric acid, iron, aluminum, calcium and magnesium. Samples were analyzed by the method, and the results for iron and aluminum agreed well with the N.B.S. standard values and the values obtained by the other company. The method can therefore be applied to the analysis of actual samples.

Hirata, H.; Arai, M.

1978-01-01

319

Aluminum structural applications  

Microsoft Academic Search

Extensive research by aluminum producers and automakers in the 1980s resulted in the development of technologies that enable building of aluminum cars that meet and exceed all the expectations of today`s drivers and passengers, yet weigh several hundred pounds less than their steel counterparts. The Acura NSX sports car, the Audi A8, and the Jaguar XJ220 have all been introduced.

1996-01-01

320

Theoretical isotope shifts in neutral barium  

NASA Astrophysics Data System (ADS)

The present work deals with a set of problems in isotope shifts of neutral barium spectral lines. Some well-known transitions (6 s2 1S0-6 s 6 p 1,3P1o and 6 s2 1S0-6 p2 3P0) are investigated. Values of the changes in the nuclear mean-square charge radius are deduced from the available experimental isotope shifts using our ab initio electronic factors. The three sets {? A ,A'} obtained from these lines are consistent with each other. The combination of the available nuclear mean-square radii with our electronic factors for the 6 s 5 d 3D1 ,2-6 s 6 p 1P1o transitions produces isotope shift values in conflict with the laser spectroscopy measurements of U. Dammalapati et al. [Eur. Phys. J. D 53, 1 (2009), 10.1140/epjd/e2009-00076-x].

Nazé, C.; Li, J. G.; Godefroid, M.

2015-03-01

321

High H? ionic conductivity in barium hydride  

NASA Astrophysics Data System (ADS)

With hydrogen being seen as a key renewable energy vector, the search for materials exhibiting fast hydrogen transport becomes ever more important. Not only do hydrogen storage materials require high mobility of hydrogen in the solid state, but the efficiency of electrochemical devices is also largely determined by fast ionic transport. Although the heavy alkaline-earth hydrides are of limited interest for their hydrogen storage potential, owing to low gravimetric densities, their ionic nature may prove useful in new electrochemical applications, especially as an ionically conducting electrolyte material. Here we show that barium hydride shows fast pure ionic transport of hydride ions (H?) in the high-temperature, high-symmetry phase. Although some conductivity studies have been reported on related materials previously, the nature of the charge carriers has not been determined. BaH2 gives rise to hydride ion conductivity of 0.2 S cm?1 at 630 °C. This is an order of magnitude larger than that of state-of-the-art proton-conducting perovskites or oxide ion conductors at this temperature. These results suggest that the alkaline-earth hydrides form an important new family of materials, with potential use in a number of applications, such as separation membranes, electrochemical reactors and so on.

Verbraeken, Maarten C.; Cheung, Chaksum; Suard, Emmanuelle; Irvine, John T. S.

2015-01-01

322

High H? ionic conductivity in barium hydride.  

PubMed

With hydrogen being seen as a key renewable energy vector, the search for materials exhibiting fast hydrogen transport becomes ever more important. Not only do hydrogen storage materials require high mobility of hydrogen in the solid state, but the efficiency of electrochemical devices is also largely determined by fast ionic transport. Although the heavy alkaline-earth hydrides are of limited interest for their hydrogen storage potential, owing to low gravimetric densities, their ionic nature may prove useful in new electrochemical applications, especially as an ionically conducting electrolyte material. Here we show that barium hydride shows fast pure ionic transport of hydride ions (H(-)) in the high-temperature, high-symmetry phase. Although some conductivity studies have been reported on related materials previously, the nature of the charge carriers has not been determined. BaH2 gives rise to hydride ion conductivity of 0.2 S cm(-1) at 630 °C. This is an order of magnitude larger than that of state-of-the-art proton-conducting perovskites or oxide ion conductors at this temperature. These results suggest that the alkaline-earth hydrides form an important new family of materials, with potential use in a number of applications, such as separation membranes, electrochemical reactors and so on. PMID:25485988

Verbraeken, Maarten C; Cheung, Chaksum; Suard, Emmanuelle; Irvine, John T S

2015-01-01

323

BLENDED CALCIUM ALUMINATE-CALCIUM SULFATE CEMENT-BASED GROUT FOR P-REACTOR VESSEL IN-SITU DECOMMISSIONING  

SciTech Connect

The objective of this report is to document laboratory testing of blended calcium aluminate - calcium hemihydrate grouts for P-Reactor vessel in-situ decommissioning. Blended calcium aluminate - calcium hemihydrate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout which has a pH greater than 12.4. In addition, blended calcium aluminate - calcium hemihydrate cement compositions can be formulated such that the primary cementitious phase is a stable crystalline material. A less alkaline material (pH {<=} 10.5) was desired to address a potential materials compatibility issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts [Wiersma, 2009a and b, Wiersma, 2010, and Serrato and Langton, 2010]. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere [Griffin, 2010, Stefanko, 2009 and Wiersma, 2009 and 2010, Bobbitt, 2010, respectively]. Radiolysis calculations are also provided in a separate document [Reyes-Jimenez, 2010].

Langton, C.; Stefanko, D.

2011-03-10

324

CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, ...  

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

CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, CALCIUM CHLORIDE STORAGE BUILDING ON RIGHT WITH SA (SODA ASH) BUILDING IN RIGHT BACKGROUND. - Solvay Process Company, Calcium Chloride Plant, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

325

82 2010 USDA Research Forum on Invasive Species GTR-NRS-P-75 MULTITROPHIC EFFECTS OF CALCIUM AVAILABILITY  

E-print Network

University of Delaware, Departments of Entomology and Wildlife Ecology, Newark, DE 19716 ABSTRACT Acid rain adsorbed to soil surfaces, and (2) aluminum is released to soil water by acid rain and displaces adsorbed, causing calcium to be more readily leached from the soil. The effects of acid rain on soil calcium

326

A case of recurrent renal aluminum hydroxide stone.  

PubMed

Renal stone disease is characterized by the differences depending on the age, gender, and the geographic location of the patients. Seventy-five percent of the renal stone components is the calcium (Ca). The most common type of the stones is the Ca oxalate stones, while Ca phosphate, uric acid, struvite, and sistine stones are more rarely reported. Other than these types, triamterene, adenosine, silica, indinavir, and ephedrine stones are also reported in the literature as case reports. However, to the best of our knowledge, aluminum hydroxide stones was not reported reported before. Herein we will report a 38-years-old woman with the history of recurrent renal colic disease whose renal stone was determined as aluminum hydroxide stone in type. Aluminum mineral may be considered in the formation of kidney stones as it is widely used in the field of healthcare and cosmetics. PMID:25013740

Cak?roglu, Basri; Dogan, Akif Nuri; Tas, Tuncay; Gozukucuk, Ramazan; Uyanik, Bekir Sami

2014-01-01

327

A Case of Recurrent Renal Aluminum Hydroxide Stone  

PubMed Central

Renal stone disease is characterized by the differences depending on the age, gender, and the geographic location of the patients. Seventy-five percent of the renal stone components is the calcium (Ca). The most common type of the stones is the Ca oxalate stones, while Ca phosphate, uric acid, struvite, and sistine stones are more rarely reported. Other than these types, triamterene, adenosine, silica, indinavir, and ephedrine stones are also reported in the literature as case reports. However, to the best of our knowledge, aluminum hydroxide stones was not reported reported before. Herein we will report a 38-years-old woman with the history of recurrent renal colic disease whose renal stone was determined as aluminum hydroxide stone in type. Aluminum mineral may be considered in the formation of kidney stones as it is widely used in the field of healthcare and cosmetics. PMID:25013740

Cak?roglu, Basri; Dogan, Akif Nuri; Tas, Tuncay; Gozukucuk, Ramazan; Uyanik, Bekir Sami

2014-01-01

328

Preparation and properties of barium ferrite using hot-rolled mill scale  

SciTech Connect

Commercial-quality barium ferrite was made on a laboratory scale by the solid-state reaction of raw hot-rolled mill scale and barium carbonate. The processing parameters are reported. The mechanism of ferrite formation is proposed.

Chien, Y.T.; Pan, H.C.; Ko, Y.C. (China Steel Corp., Kaohsiung, Taiwan (TW))

1989-08-01

329

Millimeter wave phase shifter based on ferromagnetic resonance in a hexagonal barium ferrite thin film  

E-print Network

Millimeter wave phase shifter based on ferromagnetic resonance in a hexagonal barium ferrite thin of an M-type barium ferrite BaM thin film prepared by pulsed laser deposition and a coplanar waveguide

330

Pyroelectric properties of barium strontium titanate films: Effect of thermal M. W. Cole,2  

E-print Network

Pyroelectric properties of barium strontium titanate films: Effect of thermal stresses J. Zhang,1 M pyroelectric properties of 001 -textured polycrystalline barium strontium titanate BaxSr1-xTiO3, BST films

Alpay, S. Pamir

331

Fabrication of Lotus-Type Porous Aluminum through Thermal Decomposition Method  

Microsoft Academic Search

Lotus-type porous aluminum with cylindrical pores was fabricated by unidirectional solidification through thermal decomposition\\u000a of calcium hydroxide, sodium bicarbonate, or titanium hydride. The pore-forming gas decomposed from calcium hydroxide, sodium\\u000a bicarbonate, and titanium hydride is identified as hydrogen. The elongated pores are evolved due to the solubility gap between\\u000a liquid and solid when the melt dissolving hydrogen is solidified unidirectionally.

S. Y. Kim; J. S. Park; H. Nakajima

2009-01-01

332

Acceleration of barium ions near 8000 km above an aurora  

NASA Technical Reports Server (NTRS)

A barium shaped charge, named Limerick, was released from a rocket launched from Poker Flat Research Range, Alaska, on March 30, 1982, at 1033 UT. The release took place in a small auroral breakup. The jet of ionized barium reached an altitude of 8100 km 14.5 min after release, indicating that there were no parallel electric fields below this altitude. At 8100 km the jet appeared to stop. Analysis shows that the barium at this altitude was effectively removed from the tip. It is concluded that the barium was actually accelerated upward, resulting in a large decrease in the line-of-sight density and hence the optical intensity. The parallel electric potential in the acceleration region must have been greater than 1 kV over an altitude interval of less than 200 km. The acceleration region, although presumably auroral in origin, did not seem to be related to individual auroral structures, but appeared to be a large-scale horizontal structure. The perpendicular electric field below, as deduced from the drift of the barium, was temporally and spatially very uniform and showed no variation related to individual auroral structures passing through.

Stenbaek-Nielsen, H. C.; Hallinan, T. J.; Wescott, E. M.; Foeppl, H.

1984-01-01

333

Creating unstable velocity-space distributions with barium injections  

SciTech Connect

Large Debye lengths relative to detector dimensions and the absence of confining walls makes space an attractive laboratory for studying fundamental theories of plasma instabilities. However, natural space plasmas are rarely found displaced from equilibrium enough to permit isolation and diagnosis of the controlling parameters and driving conditions. Furthermore, any plasma or field response to the departure from equilibrium can be masked by noise in the natural system. Active experiments provide a technique for addressing the chicken or egg dilemma. Early thermite barium releases were generally conducted at low altitudes from sounding rockets to trace electric fields passively or to study configuration-space instabilities. One can also study velocity-space instabilities with barium releases. Neutral barium vapor releases wherein a typical speed greatly exceeds the thermal speed can be used to produce barium ion velocity-space distributions that should be subject to a number of microinstabilities. We examine the ion velocity-space distributions resulting from barium injections from orbiting spacecraft and shaped-charges.

Pongratz, M.B.

1983-01-01

334

Aluminum, parathyroid hormone, and osteomalacia  

SciTech Connect

Aluminum exposure in man is unavoidable. The occurrence of dialysis dementia, vitamin D-resistant osteomalacia, and hypochromic microcytic anemia in dialysis patients underscores the potential for aluminum toxicity. Although exposure via dialysate and hyperalimentation leads to significant tissue aluminum accumulation, the ubiquitous occurrence of aluminum and the severe pathology associated with large aluminum burdens suggest that smaller exposures via the gastrointestinal tract and lungs could represent an important, though largely unrecognized, public health problem. It is clear that some aluminum absorption occurs with the ingestion of small amounts of aluminum in the diet and medicines, and even greater aluminum absorption is seen in individuals consuming large amounts of aluminum present in antacids. Aluminum absorption is enhanced in the presence of elevated circulating parathyroid hormone. In addition, elevated PTH leads to the preferential deposition of aluminum in brain and bone. Consequently, PTH is likely to be involved in the pathogenesis of toxicities in those organs. PTH excess also seems to lead to the deposition of aluminum in the parathyroid gland. The in vitro demonstration that aluminum inhibits parathyroid hormone release is consistent with the findings of a euparathyroid state in dialysis patients with aluminum related vitamin D-resistant osteomalacia. Nevertheless, it seems likely that hyperparathyroidism is at least initially involved in the pathogenesis of aluminum neurotoxicity and osteomalacia; the increases in tissue aluminum stores are followed by suppression of parathyroid hormone release, which is required for the evolution of osteomalacia. Impaired renal function is not a prerequisite for increased tissue aluminum burdens, nor for aluminum-related organ toxicity. Consequently, it is likely that these diseases will be observed in populations other than those with chronic renal disease.

Burnatowska-Hledin, M.A.; Kaiser, L.; Mayor, G.H.

1983-01-01

335

Fabrication of Nanoparticles of Barium Carbonate\\/Oxalate Using Reverse Micelle Technique  

Microsoft Academic Search

Nanoparticles of barium carbonate\\/oxalate have been synthesized in situ from barium nitrate and ammonium carbonate\\/oxalate by reverse micelle method. These particles were characterized using transmission electron microscope (TEM), fourier transform infrared (FTIR) and x-ray diffraction (XRD). The results indicate that rod-like barium carbonate (BaCO3) and spherical barium oxalate (BaC2O4) nanoparticles can be fabricated with high crystallinity.

Poonam Sharma; H. S. Virk

2009-01-01

336

Magnetic properties of La–Co substituted barium ferrite thin films with large magnetic anisotropy  

Microsoft Academic Search

Barium ferrite thin films with lanthanum ions and cobalt ions substituted for barium ions and iron ions have been prepared by conventional diode sputtering method. The hexagonal magnetoplumbite structure was formed by an annealing at 800°C or above. La–Co-substituted barium ferrite thin films had large magnetic anisotropy compared with non-substituted barium ferrite thin films. Moreover, an attempt was also made

K. Kakizaki; H. Taguchi; N. Hiratsuka

2004-01-01

337

Relative bioavailability of calcium from calcium formate, calcium citrate, and calcium carbonate  

E-print Network

Published Abstract: Calcium is an essential nutrient required in substantial amounts, but many diets are deficient in calcium making supplementation necessary or desirable. The objective of this study was to compare the oral bioavailability...

Hanzlik, Robert P.; Fowler, S. C.; Fisher, D. H.

2005-06-01

338

Calcium and Your Child  

MedlinePLUS

... t overlook other healthy calcium-fortified foods, including orange juice, soy products, and bread. Here are some ... 300 milligrams 8 ounces (237 milliliters) calcium-fortified orange juice 300 milligrams 2 ounces (57 grams) American ...

339

Calcium in diet  

MedlinePLUS

... Salmon and sardines canned with their soft bones Almonds, Brazil nuts, sunflower seeds, tahini, and dried beans ... greens = 220 mg of calcium 3 ounces of almonds = 210 mg of calcium Vitamin D is needed ...

340

INTERACTIONS BETWEEN MAGNESIUM, CALCIUM, AND ALUMINUM ON SOYBEAN ROOT ELONGATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alleviation of Al rhizotoxicity by Ca and Mg can differ among species and genotypes. Root elongation of soybean [Glycine max (L.) Merr.] line N93-S-179 and cvs. Young and Ransom exposed to varying concentrations of Al, Ca and Mg were compared in two experiments using a vertically split root system. ...

341

Crystal structure of complex natural aluminum magnesium calcium iron oxide  

NASA Astrophysics Data System (ADS)

The structure of a new natural oxide found near the Tashelga River (Eastern Siberia) was studied by X-ray diffraction. The pseudo-orthorhombic unit cell parameters are a = 5.6973(1) Å, b = 17.1823(4) Å, c = 23.5718(5) Å, ? = 90°, sp. gr. Pc. The structure was refined to R = 0.0516 based on 4773 reflections with | F| > 7?( F) taking into account the twin plane perpendicular to the z axis (the twin components are 0.47 and 0.53). The crystal-chemical formula ( Z = 4) is Ca2Mg{2/IV}Fe{2/(2+)IV}[Al{14/VI}O31(OH)][Al{2/IV}O][AlIV]ALIV(OH)], where the Roman numerals designate the coordination of the atoms. The structure of the mineral is based on wide ribbons of edge-sharing Al octahedra (an integral part of the spinel layer). The ribbons run along the shortest x axis and are inclined to the y and z axes. The adjacent ribbons are shifted with respect to each other along the y axis, resulting in the formation of step-like layers in which the two-ribbon thickness alternates with the three-ribbon thickness. Additional Al octahedra and Mg and Fe2+ tetrahedra are located between the ribbons. The layers are linked together to form a three-dimensional framework by Al tetrahedra, Ca polyhedra, and hydrogen bonds with the participation of OH groups.

Rastsvetaeva, R. K.; Aksenov, S. M.; Verin, I. A.

2010-07-01

342

Crystal structure of complex natural aluminum magnesium calcium iron oxide  

Microsoft Academic Search

The structure of a new natural oxide found near the Tashelga River (Eastern Siberia) was studied by X-ray diffraction. The\\u000a pseudo-orthorhombic unit cell parameters are a = 5.6973(1) Å, b = 17.1823(4) Å, c = 23.5718(5) Å, ? = 90°, sp. gr. Pc. The structure was refined to R = 0.0516 based on 4773 reflections with |F| > 7?(F) taking

R. K. Rastsvetaeva; S. M. Aksenov; I. A. Verin

2010-01-01

343

Crystal structure of complex natural aluminum magnesium calcium iron oxide  

SciTech Connect

The structure of a new natural oxide found near the Tashelga River (Eastern Siberia) was studied by X-ray diffraction. The pseudo-orthorhombic unit cell parameters are a = 5.6973(1) A, b = 17.1823(4) A, c = 23.5718(5) A, {beta} = 90{sup o}, sp. gr. Pc. The structure was refined to R = 0.0516 based on 4773 reflections with vertical bar F vertical bar > 7{sigma}(F) taking into account the twin plane perpendicular to the z axis (the twin components are 0.47 and 0.53). The crystal-chemical formula (Z = 4) is Ca{sub 2}Mg{sub 2}{sup IV}Fe{sub 2}{sup (2+)IV}[Al{sub 14}{sup VI}O{sub 31}(OH)][Al{sub 2}{sup IV}O][Al{sup IV}]AL{sup IV}(OH)], where the Roman numerals designate the coordination of the atoms. The structure of the mineral is based on wide ribbons of edge-sharing Al octahedra (an integral part of the spinel layer). The ribbons run along the shortest x axis and are inclined to the y and z axes. The adjacent ribbons are shifted with respect to each other along the y axis, resulting in the formation of step-like layers in which the two-ribbon thickness alternates with the three-ribbon thickness. Additional Al octahedra and Mg and Fe{sup 2+} tetrahedra are located between the ribbons. The layers are linked together to form a three-dimensional framework by Al tetrahedra, Ca polyhedra, and hydrogen bonds with the participation of OH groups.

Rastsvetaeva, R. K., E-mail: rast@ns.crys.ras.ru; Aksenov, S. M.; Verin, I. A. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

2010-07-15

344

Aluminum automotive space frames  

SciTech Connect

Design of aluminum structures is to a new topic. Aircraft makers have successfully solved difficult structural problems with a high degree of understanding and reliability. Other transportation modes such as trucks, trailers, and railcars have faced structural problems with some emphasis on high- and low-cycle fatigue of welded aluminum structures. However, the automotive market places stringent engineering demands on materials and superimposes demanding cost constraints. A project was instituted at Reynolds Metals Co. to investigate the opportunities for the cost-effective application of aluminum to automotive spaceframes. Several areas were recognized as key to the success of this application. They were: equivalent or superior structural stiffness of the assembly to existing steel unibody and/or steel spaceframe vehicles; effective joining of spaceframe members; equivalent or superior crashworthiness of the assembly; weight savings; flexibility; and low-cost approach aimed at effective manufacturing. To gain experience with the key aspects in a practical environment, the experience of current builders of steel tube frame chassis was explored. These chassis are typically used in low-volume vehicles requiring torsional stiffness, excellent crashworthiness, and exterior body-style flexibility. A model was developed using finite element methods that accurately predicts mass and stiffness of frames. An effective aluminum space frame was generated which was 7.5% stiffer and more than 20% lighter than the steel frame, with stresses kept below the fatigue limit for aluminum welds.

NONE

1995-08-01

345

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Barium manganese oxide (BaMnO3). 721.10010 Section...Chemical Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical...chemical substance identified as barium manganese oxide (BaMnO3 ) (PMN...

2011-07-01

346

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Barium manganese oxide (BaMnO3). 721.10010 Section...Chemical Substances § 721.10010 Barium manganese oxide (BaMnO3 ). (a) Chemical...chemical substance identified as barium manganese oxide (BaMnO3 ) (PMN...

2014-07-01

347

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Barium manganese oxide (BaMnO3). 721.10010 Section...Chemical Substances § 721.10010 Barium manganese oxide (BaMnO3 ). (a) Chemical...chemical substance identified as barium manganese oxide (BaMnO3 ) (PMN...

2012-07-01

348

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Barium manganese oxide (BaMnO3). 721.10010 Section...Chemical Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical...chemical substance identified as barium manganese oxide (BaMnO3 ) (PMN...

2010-07-01

349

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Barium manganese oxide (BaMnO3). 721.10010 Section...Chemical Substances § 721.10010 Barium manganese oxide (BaMnO3 ). (a) Chemical...chemical substance identified as barium manganese oxide (BaMnO3 ) (PMN...

2013-07-01

350

49 CFR 173.182 - Barium azide-50 percent or more water wet.  

Code of Federal Regulations, 2012 CFR

...Barium azide-50 percent or more water wet. 173.182 Section...Barium azide—50 percent or more water wet. Barium azide...to take place when and where freezing weather is possible, a suitable...solution must be used to prevent freezing. Each packaging must...

2012-10-01

351

21 CFR 201.304 - Tannic acid and barium enema preparations.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Tannic acid and barium enema preparations. 201...Specific Drug Products § 201.304 Tannic acid and barium enema preparations. (a) It has become a widespread practice for tannic acid to be added to barium enemas to...

2011-04-01

352

L = 1.24 Conjugate Magnetic Field Line Tracing Experiments With Barium Shaped Charges  

Microsoft Academic Search

Barium ions are well suited for tracing out magnetic field lines, because they resonantly scatter sunlight in several visible wavelengths and because ions are constrained to spiral about magnetic field lines while traveling freely parallel to the field. By use of high explosive shaped charges with hollow conical liners of barium metal, detonated above 500-km altitude, jets of barium plasma

E. M. Wescott; E. P. Rieger; H. C. Stenbaek-Nielsen; T. N. Davis; H. M. Peek; P. J. Bottoms

1974-01-01

353

21 CFR 201.304 - Tannic acid and barium enema preparations.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Tannic acid and barium enema preparations. 201...Specific Drug Products § 201.304 Tannic acid and barium enema preparations. (a) It has become a widespread practice for tannic acid to be added to barium enemas to...

2010-04-01

354

Synthesis of Barium Ferrite Ultrafine Particles by Coprecipitation in the Presence of Polyacrylic Acid  

Microsoft Academic Search

The barium ferrite ultrafine particles were synthesized by coprecipitation in an aqueous solution with polyacrylic acid (PAA) as a protective agent. Thermal analysis by TGA\\/DTA showed that the precursor could yield barium ferrite after calcination above 700°C for 2 h. By analyses of the XRD and electron diffraction pattern, the formation of pure barium ferrite was confirmed and the appropriate

Dong-Hwang Chen; Yuh-Yuh Chen

2001-01-01

355

Barium ferrite particulate tapes for high-band 8 mm VCR  

Microsoft Academic Search

Barium ferrite particulate media have been applied to recording tapes for a high-band 8 mm VCR, with full compatibility with metal particulate tapes, although they have remarkably different magnetic and recording characteristics. The compatibility of barium ferrite tapes to metal particulate tapes has been attained by adopting barium ferrite particles with an average diameter of 50 nm and a diameter

H. Yokoyama; T. Ito; M. Isshiki; K. Kurata; T. Fukaya

1992-01-01

356

Barium ferrite thin film media with perpendicular c-axis orientation and small grain size  

E-print Network

on the magnetic properties of stoichiometric barium ferrite thin films have been previously reported.2 In our workBarium ferrite thin film media with perpendicular c-axis orientation and small grain size Zailong, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 Barium ferrite thin films with perpendicular c

Laughlin, David E.

357

TEE BARIUM CONTENT IN THE CALCAREOUS SKELETAL MATERTALS OF SOME RECENT AND  

E-print Network

TEE BARIUM CONTENT IN THE CALCAREOUS SKELETAL MATERTALS OF SOME RECENT AND FOSSIL CORALS known mlxtures of the 'vrlo m inerals. Ion-exchange methods hrere utllized to separate barium from on ln the Ilvlng eorals varled from 5- 2 + IOS ppn, to L2.5 + 6.1+% ppr. ThtB varJ-atlon ln barium

Luther, Douglas S.

358

M-type barium hexaferrite synthesis and characterization for phase shifter applications  

E-print Network

M-type barium hexaferrite synthesis and characterization for phase shifter applications A. T. Wise; published online 13 April 2011) M-type barium hexaferrite films have been grown by liquid phase epitaxy half a percent. VC 2011 American Institute of Physics. [doi:10.1063/1.3559471] Since M-type barium

McHenry, Michael E.

359

49 CFR 173.182 - Barium azide-50 percent or more water wet.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Barium azide-50 percent or more water wet. 173...Other Than Class 1 and Class 7 § 173.182 Barium azide—50 percent or more water wet. Barium azide—50 percent or more water wet,...

2013-10-01

360

PHYSICAL REVIEW A 88, 023403 (2013) Production of translationally cold barium monohalide ions  

E-print Network

PHYSICAL REVIEW A 88, 023403 (2013) Production of translationally cold barium monohalide ions M. V) We have produced sympathetically cooled barium monohalide ions BaX+ (X = F, Cl, Br) by reacting with these predictions. Producing BaX+ ions in this way is simple and allows for the study of different barium monohalide

Chapman, Michael

2013-01-01

361

21 CFR 201.304 - Tannic acid and barium enema preparations.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Tannic acid and barium enema preparations. 201.304 Section...Products § 201.304 Tannic acid and barium enema preparations. (a) It has...practice for tannic acid to be added to barium enemas to improve X-ray...

2014-04-01

362

Spectroscopy of Eu3+ ions in congruent strontium barium niobate crystals  

E-print Network

Spectroscopy of Eu3+ ions in congruent strontium barium niobate crystals Ä. Andresen, A.-N. Bahar properties of single crystals of strontium barium niobate, grown from the congruently melting composition, electro-optic, pho- torefractive, and dielectric properties, the solid solution strontium barium niobate

Osnabrück, Universität

363

49 CFR 173.182 - Barium azide-50 percent or more water wet.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Barium azide-50 percent or more water wet. 173...Other Than Class 1 and Class 7 § 173.182 Barium azide—50 percent or more water wet. Barium azide—50 percent or more water wet,...

2014-10-01

364

21 CFR 201.304 - Tannic acid and barium enema preparations.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Tannic acid and barium enema preparations. 201.304 Section...Products § 201.304 Tannic acid and barium enema preparations. (a) It has...practice for tannic acid to be added to barium enemas to improve X-ray...

2013-04-01

365

A comparison between excess barium and barite as indicators of carbon export  

E-print Network

A comparison between excess barium and barite as indicators of carbon export Meagan Eagle and Adina in many paleoproductivity studies. Barite, the main carrier of particulate barium in the water column in some locations. We demonstrate that Baexcess (total barium minus the fraction associated

Paytan, Adina

366

MNRAS 428, 32523261 (2013) doi:10.1093/mnras/sts270 Barium abundances in Cepheids  

E-print Network

MNRAS 428, 3252­3261 (2013) doi:10.1093/mnras/sts270 Barium abundances in Cepheids S. M. Andrievsky; in original form 2012 August 28 ABSTRACT We derived the barium atmospheric abundances for a large sample to 15 kpc, so it is appropriate to investigate the existence of radial barium abundance gradients

Maciel, Walter Junqueira

2013-01-01

367

Compact high power barium nitrite crystal-based Raman laser at 1197 nm  

E-print Network

Compact high power barium nitrite crystal-based Raman laser at 1197 nm for photoacoustic imaging of fat Rui Li Mikhail N. Slipchenko Pu Wang Ji-Xin Cheng #12;Compact high power barium nitrite crystal such a barrier, we demonstrate the construction and use of a com- pact, barium nitrite crystal-based Raman laser

Cheng, Ji-Xin

368

Discrete barite particles and barium as tracers of paleoproductivity in South Atlantic sediments  

Microsoft Academic Search

Geochemical analyses as well as X ray diffraction measurements were carried out on five sediment cores from the eastern Angola Basin and the equatorial divergence of the South Atlantic. Barite concentrations were calculated from total barium concentrations by subtracting the estimated barium background supplied by ``nonbarite'' barium carriers. Barite concentrations assessed by this geochemical method show a good correspondence to

Franz Gingele; Andreas Dahmke

1994-01-01

369

49 CFR 173.182 - Barium azide-50 percent or more water wet.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Barium azide-50 percent or more water wet. 173...Other Than Class 1 and Class 7 § 173.182 Barium azide—50 percent or more water wet. Barium azide—50 percent or more water wet,...

2010-10-01

370

PHYSICAL REVIEW A 81, 052328 (2010) Hyperfine and optical barium ion qubits  

E-print Network

PHYSICAL REVIEW A 81, 052328 (2010) Hyperfine and optical barium ion qubits M. R. Dietrich,* N these profoundly quantum systems. Despite a long history in ion trapping [3­5], barium has never previously been a natural source without isotope-selective ionization [6,7]. Barium possesses a long-lived metastable state

Blinov, Boris

2010-01-01

371

M-type barium hexaferrite synthesis and characterization for phase shifter applications  

E-print Network

M-type barium hexaferrite synthesis and characterization for phase shifter applications A. T. Wise subject to AIP license or copyright; see http://jap.aip.org/about/rights_and_permissions #12;M-type barium-type barium hexaferrite films have been grown by liquid phase epitaxy and examined by x-ray diffraction

Laughlin, David E.

372

21 CFR 201.304 - Tannic acid and barium enema preparations.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Tannic acid and barium enema preparations. 201.304 Section...Products § 201.304 Tannic acid and barium enema preparations. (a) It has...practice for tannic acid to be added to barium enemas to improve X-ray...

2012-04-01

373

1 Barium and carbon fluxes in the Canadian Arctic Archipelago 2 Helmuth Thomas,1  

E-print Network

1 Barium and carbon fluxes in the Canadian Arctic Archipelago 2 Helmuth Thomas,1 Elizabeth Shadwick Barium (Ba) in the Amundsen Gulf, 8 southeastern Beaufort Sea, was monitored over a full year from observed at river mouths, the lowest concentrations are found in water 12 masses of Atlantic origin. Barium

Boyer, Edmond

374

Phase associations of barium in marine sediments Meagan Eagle Gonneea *, Adina Paytan 1  

E-print Network

Phase associations of barium in marine sediments Meagan Eagle Gonneea *, Adina Paytan 1 Department 2006 Abstract Barium (Ba) is associated with various phases in marine sediments, including carbonates-export productivity. D 2005 Elsevier B.V. All rights reserved. Keywords: Barium; Barite; Marine sediment; Sedimentary

Paytan, Adina

375

Noncollinear Optical Frequency Doubling in Strontium Barium Niobate Arthur R. Tunyagi, Michael Ulex, and Klaus Betzler*  

E-print Network

Noncollinear Optical Frequency Doubling in Strontium Barium Niobate Arthur R. Tunyagi, Michael Ulex of a novel noncollinear optical second-harmonic generation mechanism is reported. In strontium barium niobate mechanism which we detected in crystals of strontium barium niobate (SBN)--cone-shaped second

Osnabrück, Universität

376

49 CFR 173.182 - Barium azide-50 percent or more water wet.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Barium azide-50 percent or more water wet. 173...Other Than Class 1 and Class 7 § 173.182 Barium azide—50 percent or more water wet. Barium azide—50 percent or more water wet,...

2011-10-01

377

Optogalvanic detection of barium high-lying levels with a two-step pulsed laser excitation  

E-print Network

L-513 Optogalvanic detection of barium high-lying levels with a two-step pulsed laser excitation P barium have been investigated by using a two-step pulsed laser excitation combined with an optogalvanic number for the ground state. In barium the ground level has a J = 0 value, so with a two- photon process

Boyer, Edmond

378

Introduction Strontium Barium Niobate k-Space Spectroscopy Results Conclusions Unraveling Relaxor Phase Transitions by  

E-print Network

Introduction Strontium Barium Niobate k-Space Spectroscopy Results Conclusions Unraveling Relaxor 2009 WILLIAMSBURG WORKSHOP ON FUNDAMENTAL PHYSICS OF FERROELECTRICS #12;Introduction Strontium Barium ferroelectrics Introduction Strontium Barium Niobate k-Space Spectroscopy Results Conclusions SBN ­ SrxBa1-xNb2O6

Osnabrück, Universität

379

75 FR 36629 - Barium Chloride From the People's Republic of China: Continuation of Antidumping Duty Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Trade Administration [A-570-007] Barium Chloride From the People's Republic...revocation of the antidumping duty order on barium chloride from the People's Republic...review of the antidumping duty order on barium chloride from the PRC pursuant to...

2010-06-28

380

Influence of Ba content on grain size and dynamics of crystallization in barium ferrite thin films  

E-print Network

Influence of Ba content on grain size and dynamics of crystallization in barium ferrite thin films of the crystallization process, which ultimately determines the grain size, were studied in barium ferrite thin films. Rapid thermal annealing was used to crystallize the amorphous as-deposited barium ferrite films

Laughlin, David E.

381

Processing of yttrium-doped barium zirconate for high proton conductivity  

E-print Network

Processing of yttrium-doped barium zirconate for high proton conductivity Peter Babilo Materials the transport properties of yttrium-doped barium zirconate (BYZ) have been explored, with the aim of attaining are arguably those of Iguchi et al.1 Using yttrium-doped barium cerate as an electrolyte, these authors

382

The enhanced and optimal piezoelectric coefficients in single crystalline barium titanate with engineered domain configurations  

E-print Network

The enhanced and optimal piezoelectric coefficients in single crystalline barium titanate the effective electromechanical moduli of tetragonal barium titanate poled along 111 direction, where that poling along 111 direction does not lead to the optimal domain configuration, since barium titanate poled

Li, Jiangyu

383

Discrete Barium Strontium Titanate (BST) Thin-Film Interdigital Varactors on Alumina: Design, Fabrication, Characterization, and  

E-print Network

Discrete Barium Strontium Titanate (BST) Thin-Film Interdigital Varactors on Alumina: Design, Raleigh, NC-27695-7914, USA. Email:jayeshnath@ieee.org Abstract -- Discrete Barium Strontium Titanate (BST, capacitors, BST, ferroelectric, thin-film, barium strontium titanate, bandpass filter, IP3, ACPR, temperature

384

Dielectric tunability of graded barium strontium titanate multilayers: Effect of thermal strains  

E-print Network

Dielectric tunability of graded barium strontium titanate multilayers: Effect of thermal strains M TEC of a multilayered barium strontium titanate Ba1-ySryTiO3 BST ferroelectric heterostructure such as barium strontium titanate Ba1-ySryTiO3 BST have emerged as leading candidates for such applications due

Alpay, S. Pamir

385

Nanoscale Patterning of Barium Titanate on Block Tu Lee,, Nan Yao, and Ilhan A. Aksay*,,  

E-print Network

Nanoscale Patterning of Barium Titanate on Block Copolymers Tu Lee,, Nan Yao, and Ilhan A. Aksay of polystyrene-polybutadiene-polystyrene (Kraton D1102) has been used to pattern barium titanate precursor on the unsaturated carbon bonds in the polybutadiene matrix with antistereochemistry. Anchoring the barium titanate

Aksay, Ilhan A.

386

Effect of depolarization and coercivity on actuation strains due to domain switching in barium titanate  

E-print Network

. The theoretical maximum actuation strain such as 1.1% for barium titanate crystals, however, has not been observed in thermally aged barium titanate BaTiO3 crystals.2 Burcsu et al. examined the 90°- switching-induced strainEffect of depolarization and coercivity on actuation strains due to domain switching in barium

Shu, Yi-Chung

387

Optimization of High Tunability Barium Strontium Titanate Thin Films Grown by RF Magnetron  

E-print Network

Optimization of High Tunability Barium Strontium Titanate Thin Films Grown by RF Magnetron Abstract-- Barium strontium titanate is a solid solution perovskite with a field-dependent permittivity.7 MV/cm. I. INTRODUCTION In recent years there has been much interest in thin-film barium strontium

York, Robert A.

388

Effect of Microwave Frequency on Hydrothermal Synthesis of Nanocrystalline Tetragonal Barium Titanate  

E-print Network

, 2007; ReVised Manuscript ReceiVed: April 29, 2008 Nanocrystalline tetragonal barium titanate (BaTiO3. The dependence of properties of barium titanate on microwave frequency could be due to different transverse titanate with different morphol- ogies, particle sizes, and dispersions. Barium titanate exists in several

Dutta, Prabir K.

389

Polyaniline stabilized barium titanate nanoparticles reinforced epoxy nanocomposites with high dielectric  

E-print Network

Polyaniline stabilized barium titanate nanoparticles reinforced epoxy nanocomposites with high*b and Zhanhu Guo*a Epoxy polymer nanocomposites (PNCs) filled with both barium titanate (BaTiO3) (500 and 100 systems.7 Barium titanate (BaTiO3) exhibiting unique ferroelectricity,8 piezoelectricity9 and high

Guo, John Zhanhu

390

Barium Titanate Nanoparticles in Block Copolymer Tu Lee,*,, Nan Yao, Hiroaki Imai,, and Ilhan A. Aksay,  

E-print Network

Barium Titanate Nanoparticles in Block Copolymer Tu Lee,*,, Nan Yao, Hiroaki Imai,, and Ilhan A-polybutadiene-polystyrene (Kraton D1102). The barium titanated Kraton thin film had remnants of the cylindrical morphology of a plain Kraton thin film with an interdomain spacing of 23 nm. The procedure of barium titanation

Aksay, Ilhan A.

391

Shape-Controlled Monocrystalline Ferroelectric Barium Titanate Nanostructures: From Nanotubes and Nanowires to Ordered Nanostructures  

E-print Network

Shape-Controlled Monocrystalline Ferroelectric Barium Titanate Nanostructures: From Nanotubes of barium titanate nanostructures using Na2Ti3O7 nanotubes and nanowires as synthetic precursors. A variety and nanowires and the temperature- dependent crystal structure of barium titanate. Various nanoblocks, including

Srinivasan, Gopalan

392

Strain effect on coercive field of epitaxial barium titanate thin films S. Choudhury,1,a  

E-print Network

Strain effect on coercive field of epitaxial barium titanate thin films S. Choudhury,1,a Y. L. Li,1 polarizations of 001 -oriented epitaxial barium titanate thin films using the phase-field approach by strain. We use 001 -oriented epitaxial barium titanate BTO thin films as a model system. In the phase

Chen, Long-Qing

393

Single-crystal barium titanate thin films by ion slicing T. Izuhara,a)  

E-print Network

Single-crystal barium titanate thin films by ion slicing T. Izuhara,a) I.-L. Gheorma, and R. M, D.C. 20052 Received 19 September 2002; accepted 3 December 2002 Thin barium titanate films, 0.5­8 m.1063/1.1540727 Barium titanate, BaTiO3 BTO , is a ferroelectric crystal whose outstanding electrical and optical

Reeves, Mark E.

394

The effect of stress on the dielectric properties of barium strontium titanate thin films  

E-print Network

The effect of stress on the dielectric properties of barium strontium titanate thin films T. M Barium strontium titanate thin films are being developed as capacitors in dynamic random access memories to their large permittivities, barium strontium titan- ate BST bulk ceramics have long been used to make high

Suo, Zhigang

395

Single-Crystalline Barium Titanate By Jeffrey J. Urban, Jonathan E. Spanier, Lian Ouyang,  

E-print Network

Single-Crystalline Barium Titanate Nanowires By Jeffrey J. Urban, Jonathan E. Spanier, Lian Ouyang composed of barium titanate (BaTiO3), a prototypical displacive ferroelectric material[14,15] that yields-volatile memory devices with an integration density approaching 1 terabit cm±2 . 2. Synthesis of Barium Titanate

Heller, Eric

396

High tunability barium strontium titanate thin films for rf circuit applications  

E-print Network

High tunability barium strontium titanate thin films for rf circuit applications N. K. Pervez,a) P) Large variations in the permittivity of rf magnetron sputtered thin-film barium strontium titanate have/cm. © 2004 American Institute of Physics. [DOI: 10.1063/1.1818724] Barium strontium titanate (BST) is a solid

York, Robert A.

397

Operation of multiple 90 switching systems in barium titanate single crystals under electromechanical loading  

E-print Network

Operation of multiple 90° switching systems in barium titanate single crystals under Hysteresis evolution of a 5 5 2 mm3 barium titanate single crystal during a combined electromechanical of barium titanate BaTiO3 single crystals under combined electrical and mechanical loadings was examined

Shu, Yi-Chung

398

Phase diagrams and dielectric response of epitaxial barium strontium titanate films: A theoretical analysis  

E-print Network

Phase diagrams and dielectric response of epitaxial barium strontium titanate films: A theoretical for publication 7 March 2002 We develop phase diagrams for single-domain epitaxial barium strontium titanate films. DOI: 10.1063/1.1473675 I. INTRODUCTION Thin films of barium strontium titanate BaxSr1 xTiO3 ,(BST

Alpay, S. Pamir

399

Optimization of the tunability of barium strontium titanate films via epitaxial stresses  

E-print Network

Optimization of the tunability of barium strontium titanate films via epitaxial stresses Z.-G. Ban The tunability of epitaxial barium strontium titanate films is analyzed theoretically using a phenomenological.1063/1.1524310 I. INTRODUCTION Thin films of barium strontium titanate (BaxSr1 xTiO3, BST have long been recognized

Alpay, S. Pamir

400

Fabrication, characterization and microwave properties of polyurethane nanocomposites reinforced with iron oxide and barium titanate  

E-print Network

with iron oxide and barium titanate nanoparticles Z. Guo a,*, S.-E. Lee a , H. Kim a , S. Park a , H.T. Hahn the introduction of the dielectric barium titanate nanoparticle into Fe2O3/PU nanocomposites. The permeability (PU) nanocomposites reinforced with magnetic iron oxide nanoparticles and/or dielectric barium

Guo, John Zhanhu

401

Microwave dielectric properties of graded barium strontium titanate films M. W. Cole,1,a  

E-print Network

Microwave dielectric properties of graded barium strontium titanate films M. W. Cole,1,a C. V, delay lines, filters, and phase shifters for steerable antennas.1­3 Barium strontium titanate BaxSr1-x Received 8 April 2008; accepted 13 April 2008; published online 8 May 2008 Compositionally graded barium

Alpay, S. Pamir

402

Journal of Crystal Growth 300 (2007) 330335 Growth and optical property characterization of textured barium  

E-print Network

of textured barium titanate thin films for photonic applications Matthew J. DickenÃ?, Kenneth Diest, Young layers on amorphous and silicon substrates. Growth of highly oriented barium titanate films of the thin films grown with and without oxygen plasma. We have shown that optical quality barium titanate

Atwater, Harry

403

Structure evolution and dielectric behavior of polystyrene-capped barium titanate nanoparticles  

E-print Network

Structure evolution and dielectric behavior of polystyrene-capped barium titanate nanoparticles H35600g Polystyrene-capped barium titanate (BaTiO3) nanoparticles with sizes of 11 nm and 27 nm were nanocrystals. 1. Introduction Barium titanate (BaTiO3), one of the most commonly used perovskite compounds

Lin, Zhiqun

404

ALUMINUM RECLAMATION BY ACIDIC EXTRACTION OF ALUMINUM-ANODIZING SLUDGES  

EPA Science Inventory

Extraction of aluminum-anodizing sludges with sulfuric acid was examined to determine the potential for production of commercial-strength solutions of aluminum sulfate, that is liquid alum. The research established kinetic and stoichiometric relationships and evaluates product qu...

405

Calcium and Mitosis  

NASA Technical Reports Server (NTRS)

Although the mechanism of calcium regulation is not understood, there is evidence that calcium plays a role in mitosis. Experiments conducted show that: (1) the spindle apparatus contains a highly developed membrane system that has many characteristics of sarcoplasmic reticulum of muscle; (2) this membrane system contains calcium; and (3) there are ionic fluxes occurring during mitosis which can be seen by a variety of fluorescence probes. Whether the process of mitosis can be modulated by experimentally modulating calcium is discussed.

Hepler, P.

1983-01-01

406

Calcium absorption and achlorhydria  

Microsoft Academic Search

Defective absorption of calcium has been thought to exist in patients with achlorhydria. The author compared absorption of calcium in its carbonate form with that in a pH-adjusted citrate form in a group of 11 fasting patients with achlorhydria and in 9 fasting normal subjects. Fractional calcium absorption was measured by a modified double-isotope procedure with 0.25 g of calcium

Robert R. Recker

1985-01-01

407

Calcium and magnesium disorders.  

PubMed

Hypocalcemia is a clinical disorder that can be life threatening to the cow (milk fever) and predisposes the animal to various other metabolic and infectious disorders. Calcium homeostasis is mediated primarily by parathyroid hormone, which stimulates bone calcium resorption and renal calcium reabsorption. Parathyroid hormone stimulates the production of 1,25-dihydroxyvitamin D to enhance diet calcium absorption. High dietary cation-anion difference interferes with tissue sensitivity to parathyroid hormone. Hypomagnesemia reduces tissue response to parathyroid hormone. PMID:24980727

Goff, Jesse P

2014-07-01

408

Concentrations of lead, cadmium and barium in urban garden-grown vegetables: the impact of soil variables.  

PubMed

Paired vegetable/soil samples from New York City and Buffalo, NY, gardens were analyzed for lead (Pb), cadmium (Cd) and barium (Ba). Vegetable aluminum (Al) was measured to assess soil adherence. Soil and vegetable metal concentrations did not correlate; vegetable concentrations varied by crop type. Pb was below health-based guidance values (EU standards) in virtually all fruits. 47% of root crops and 9% of leafy greens exceeded guidance values; over half the vegetables exceeded the 95th percentile of market-basket concentrations for Pb. Vegetable Pb correlated with Al; soil particle adherence/incorporation was more important than Pb uptake via roots. Cd was similar to market-basket concentrations and below guidance values in nearly all samples. Vegetable Ba was much higher than Pb or Cd, although soil Ba was lower than soil Pb. The poor relationship between vegetable and soil metal concentrations is attributable to particulate contamination of vegetables and soil characteristics that influence phytoavailability. PMID:25163429

McBride, Murray B; Shayler, Hannah A; Spliethoff, Henry M; Mitchell, Rebecca G; Marquez-Bravo, Lydia G; Ferenz, Gretchen S; Russell-Anelli, Jonathan M; Casey, Linda; Bachman, Sharon

2014-11-01

409

White dwarf kicks and implications for barium stars  

NASA Astrophysics Data System (ADS)

The barium stars have caused much grief in the field of binary stellar evolution. They are often eccentric when they should be circular and are not found to have periods longer than 104 days even though wind accretion should still be efficient at such separations. We address both these problems by introducing a kick to white dwarfs when they are born, thus solving the eccentricity problem, and imposing strong orbital angular momentum loss to shrink barium-star binaries down to the observed periods. Whilst our angular momentum prescription is hard to justify for the barium stars it shows that strong angular momentum loss is necessary to reproduce the observed period-eccentricity distribution. We are investigating whether this can be obtained from a circumbinary disc.

Izzard, R. G.; Church, R. P.; Dermine, T.

410

Barium Levels in Soils and Centella asiatica.  

PubMed

In this study, Centella asiatica and surface soils were collected from 12 sampling sites in Peninsular Malaysia, and the barium (Ba) concentrations were determined. The Ba concentration [?g/g dry weight (dw)] was 63.72 to 382.01 ?g/g in soils while in C. asiatica, Ba concentrations ranged from 5.05 to 21.88 ?g/g for roots, 3.31 to 11.22 ?g/g for leaves and 2.37 to 6.14 ?g/g for stems. In C. asiatica, Ba accumulation was found to be the highest in roots followed by leaves and stems. The correlation coefficients (r) of Ba between plants and soils were found to be significantly positively correlated, with the highest correlation being between roots-soils (r=0.922, p<005), followed by leaves-soils (r=0.890, p<005) and stems-soils (r=0.848, p<005). This indicates that these three parts of C. asiatica are good biomonitors of Ba pollution. For the transplantation study, four sites were selected as unpolluted [(Universiti Putra Malaysia (UPM)], semi-polluted (Seri Kembangan and Balakong) and polluted sites (Juru). Based on the transplantation study under experimental field and laboratory conditions, Ba concentrations in C. asiatica were significantly (p<0.05) higher after three weeks of exposure at Seri Kembangan, Balakong and Juru. Thus, these experimental findings confirm that the leaves, stems and roots of C. asiatica can reflect the Ba levels in the soils where this plant is found. Three weeks after back transplantation to clean soils, the Ba levels in C. asiatica were still higher than the initial Ba level even though Ba elimination occurred. In conclusion, the leaves, stems and roots of C. asiatica are good biomonitors of Ba pollution. PMID:24575242

Ong, Ghim Hock; Yap, Chee Kong; Mahmood, Maziah; Tan, Soon Guan; Hamzah, Suhaimi

2013-08-01

411

Selectivity in biomineralization of barium and strontium.  

PubMed

The desmid green alga Closterium moniliferum belongs to a small number of organisms that form barite (BaSO(4)) or celestite (SrSO(4)) biominerals. The ability to sequester Sr in the presence of an excess of Ca is of considerable interest for the remediation of (90)Sr from the environment and nuclear waste. While most cells dynamically regulate the concentration of the second messenger Ca(2+) in the cytosol and various organelles, transport proteins rarely discriminate strongly between Ca, Sr, and Ba. Herein, we investigate how these ions are trafficked in C. moniliferum and how precipitation of (Ba,Sr)SO(4) crystals occurs in the terminal vacuoles. Towards this goal, we simultaneously visualize intracellular dynamics of multiple elements using X-ray fluorescence microscopy (XFM) of cryo-fixed/freeze-dried samples. We correlate the resulting elemental maps with ultrastructural information gleaned from freeze-fracture cryo-SEM of frozen-hydrated cells and use micro X-ray absorption near edge structure (micro-XANES) to determine sulfur speciation. We find that the kinetics of Sr uptake and efflux depend on external Ca concentrations, and Sr, Ba, and Ca show similar intracellular localization. A highly ion-selective cross-membrane transport step is not evident. Based on elevated levels of sulfate detected in the terminal vacuoles, we propose a "sulfate trap" model, where the presence of dissolved barium leads to preferential precipitation of (Ba,Sr)SO(4) due to its low solubility relative to SrSO(4) and CaSO(4). Engineering the sulfate concentration in the vacuole may thus be the most direct way to increase the Sr sequestered per cell, an important consideration in using desmids for phytoremediation of (90)Sr. PMID:21871966

Krejci, Minna R; Wasserman, Brian; Finney, Lydia; McNulty, Ian; Legnini, Daniel; Vogt, Stefan; Joester, Derk

2011-11-01

412

Timed barium esophagram in achalasia types.  

PubMed

Relationships of timed barium esophagram (TBE) findings to achalasia types defined by high-resolution manometry (HRM) have not been elucidated. Therefore, we correlated preoperative TBE and HRM measurements in achalasia types and related these to patient symptoms and prior treatments. From 2006 to 2013, 248 achalasia patients underwent TBE and HRM before Heller myotomy. TBE height and width were recorded at 1 and 5 minutes; HRM measured lower esophageal sphincter mean basal pressure, integrated relaxation pressure (IRP), and mean esophageal body contraction amplitude. Achalasia was classified into types I (25%), II (65%), and III (9.7%). TBE height at 5 minutes was higher for I (median 8?cm; interquartile range 6-12) and II (8?cm; 8-11) than for III (1?cm; 0-7). TBE width at 5 minutes was widest (3?cm; 2-4), narrower in II (2?cm; 2-3), and narrowest in I (1?cm; 0-2), P?

Zanoni, A; Rice, T W; Lopez, R; Birgisson, S; Shay, S S; Thota, P N; Baker, M E; Raymond, D P; Blackstone, E H

2015-05-01

413

Barium Levels in Soils and Centella asiatica  

PubMed Central

In this study, Centella asiatica and surface soils were collected from 12 sampling sites in Peninsular Malaysia, and the barium (Ba) concentrations were determined. The Ba concentration [?g/g dry weight (dw)] was 63.72 to 382.01 ?g/g in soils while in C. asiatica, Ba concentrations ranged from 5.05 to 21.88 ?g/g for roots, 3.31 to 11.22 ?g/g for leaves and 2.37 to 6.14 ?g/g for stems. In C. asiatica, Ba accumulation was found to be the highest in roots followed by leaves and stems. The correlation coefficients (r) of Ba between plants and soils were found to be significantly positively correlated, with the highest correlation being between roots-soils (r=0.922, p<005), followed by leaves-soils (r=0.890, p<005) and stems-soils (r=0.848, p<005). This indicates that these three parts of C. asiatica are good biomonitors of Ba pollution. For the transplantation study, four sites were selected as unpolluted [(Universiti Putra Malaysia (UPM)], semi-polluted (Seri Kembangan and Balakong) and polluted sites (Juru). Based on the transplantation study under experimental field and laboratory conditions, Ba concentrations in C. asiatica were significantly (p<0.05) higher after three weeks of exposure at Seri Kembangan, Balakong and Juru. Thus, these experimental findings confirm that the leaves, stems and roots of C. asiatica can reflect the Ba levels in the soils where this plant is found. Three weeks after back transplantation to clean soils, the Ba levels in C. asiatica were still higher than the initial Ba level even though Ba elimination occurred. In conclusion, the leaves, stems and roots of C. asiatica are good biomonitors of Ba pollution. PMID:24575242

Ong, Ghim Hock; Yap, Chee Kong; Mahmood, Maziah; Tan, Soon Guan; Hamzah, Suhaimi

2013-01-01

414

Calcium and Vitamin D  

Technology Transfer Automated Retrieval System (TEKTRAN)

This chapter describes the roles of calcium and vitamin D in bone health. Calcium is required for the bone formation phase of bone remodeling and it also affects bone mass through its impact on the remodeling rate. Typically, about 5 nmol (200 mg) of calcium is removed from the adult skeleton and ...

415

RESEARCH ARTICLE CALCIUM CHANNEL STRUCTURE  

E-print Network

RESEARCH ARTICLE CALCIUM CHANNEL STRUCTURE Structural basis for a pH-sensitive calcium leak across,3 Wayne A. Hendrickson,1,2,4,5 Qun Liu1,4 * Calcium homeostasis balances passive calcium leak and active calcium uptake. Human Bax inhibitor­1 (hBI-1) is an antiapoptotic protein that mediates a calcium leak

Napp, Nils

416

Contribution of calcium oxalate to soil-exchangeable calcium  

USGS Publications Warehouse

Acid deposition and repeated biomass harvest have decreased soil calcium (Ca) availability in many temperate forests worldwide, yet existing methods for assessing available soil Ca do not fully characterize soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it has been hypothesized that the highly insoluble biomineral Ca oxalate might represent an additional soil Ca pool that is not detected in standard measures of soil-exchangeable Ca. We asked whether several standard method extractants for soil-exchangeable Ca could also access Ca held in Ca oxalate crystals using spike recovery tests in both pure solutions and soil extractions. In solutions of the extractants ammonium chloride, ammonium acetate, and barium chloride, we observed 2% to 104% dissolution of Ca oxalate crystals, with dissolution increasing with both solution molarity and ionic potential of cation extractant. In spike recovery tests using a low-Ca soil, we estimate that 1 M ammonium acetate extraction dissolved sufficient Ca oxalate to contribute an additional 52% to standard measurements of soil-exchangeable Ca. However, in a high-Ca soil, the amount of Ca oxalate spike that would dissolve in 1 M ammonium acetate extraction was difficult to detect against the large pool of exchangeable Ca. We conclude that Ca oxalate can contribute substantially to standard estimates of soil-exchangeable Ca in acid forest soils with low soil-exchangeable Ca. Consequently, measures of exchangeable Ca are unlikely to fully resolve discrepancies in ecosystem Ca mass balance unless the contribution of Ca oxalate to exchangeable Ca is also assessed.

Dauer, Jenny M.; Perakis, Steven S.

2013-01-01

417

Ca2+ released from calcium alginate gels can promote inflammatory responses in vitro and in vivo  

PubMed Central

In general, alginate hydrogels are considered to be biologically inert and are commonly used for biomedical purposes that require minimum inflammation. However, Ca2+, which is commonly used to crosslink alginate, is a critical second messenger in immune cell signaling, and little has been done to understand its effect on immune cell fate when delivered as a component of alginate gels. We found that dendritic cells (DCs) encapsulated in Ca2+-crosslinked alginate (calcium alginate) secreted at least fivefold more of the inflammatory cytokine IL-1? when compared to DCs encapsulated in agarose and collagen gels, as well as DCs plated on tissue-culture polystyrene (TCPS). Plating cells on TCPS with the alginate polymer could not reproduce these results, whereas culturing DCs on TCPS with increasing concentrations of Ca2+ increased IL-1?, MHC class II and CD86 expression in a dose-dependent manner. In agreement with these findings, calcium alginate gels induced greater maturation of encapsulated DCs compared to barium alginate gels. When injected subcutaneously in mice, calcium alginate gels significantly upregulated IL-1? secretion from surrounding tissue relative to barium alginate gels, and similarly, the inflammatory effects of LPS were enhanced when it was delivered from calcium alginate gels rather than barium alginate gels. These results confirm that the Ca2+ used to crosslink alginate gels can be immunostimulatory and suggest that it is important to take into account Ca2+’s bioactive effects on all exposed cells (both immune and non-immune) when using calcium alginate gels for biomedical purposes. This work may strongly impact the way people use alginate gels in the future as well as provide insights into past work utilizing alginate gels. PMID:23938198

Chan, Gail; Mooney, David J.

2013-01-01

418

Compact pulse forming line using barium titanate ceramic material.  

PubMed

Ceramic material has very high relative permittivity, so compact pulse forming line can be made using these materials. Barium titanate (BaTiO(3)) has a relative permittivity of 1200 so it is used for making compact pulse forming line (PFL). Barium titanate also has piezoelectric effects so it cracks during high voltages discharges due to stresses developed in it. Barium titanate is mixed with rubber which absorbs the piezoelectric stresses when the PFL is charged and regain its original shape after the discharge. A composite mixture of barium titanate with the neoprene rubber is prepared. The relative permittivity of the composite mixture is measured to be 85. A coaxial pulse forming line of inner diameter 120 mm, outer diameter 240 mm, and length 350 mm is made and the composite mixture of barium titanate and neoprene rubber is filled between the inner and outer cylinders. The PFL is charged up to 120 kV and discharged into 5 ? load. The voltage pulse of 70 kV, 21 ns is measured across the load. The conventional PFL is made up of oil or plastics dielectrics with the relative permittivity of 2-10 [D. R. Linde, CRC Handbook of Chemistry and Physics, 90th ed. (CRC, 2009); Xia et al., Rev. Sci. Instrum. 79, 086113 (2008); Yang et al., Rev. Sci. Instrum. 81, 43303 (2010)], which increases the length of PFL. We have reported the compactness in length achieved due to increase in relative permittivity of composite mixture by adding barium titanate in neoprene rubber. PMID:22129008

Kumar Sharma, Surender; Deb, P; Shukla, R; Prabaharan, T; Shyam, A

2011-11-01

419

Compact pulse forming line using barium titanate ceramic material  

NASA Astrophysics Data System (ADS)

Ceramic material has very high relative permittivity, so compact pulse forming line can be made using these materials. Barium titanate (BaTiO3) has a relative permittivity of 1200 so it is used for making compact pulse forming line (PFL). Barium titanate also has piezoelectric effects so it cracks during high voltages discharges due to stresses developed in it. Barium titanate is mixed with rubber which absorbs the piezoelectric stresses when the PFL is charged and regain its original shape after the discharge. A composite mixture of barium titanate with the neoprene rubber is prepared. The relative permittivity of the composite mixture is measured to be 85. A coaxial pulse forming line of inner diameter 120 mm, outer diameter 240 mm, and length 350 mm is made and the composite mixture of barium titanate and neoprene rubber is filled between the inner and outer cylinders. The PFL is charged up to 120 kV and discharged into 5 ? load. The voltage pulse of 70 kV, 21 ns is measured across the load. The conventional PFL is made up of oil or plastics dielectrics with the relative permittivity of 2-10 [D. R. Linde, CRC Handbook of Chemistry and Physics, 90th ed. (CRC, 2009); Xia et al., Rev. Sci. Instrum. 79, 086113 (2008); Yang et al., Rev. Sci. Instrum. 81, 43303 (2010)], which increases the length of PFL. We have reported the compactness in length achieved due to increase in relative permittivity of composite mixture by adding barium titanate in neoprene rubber.

Kumar Sharma, Surender; Deb, P.; Shukla, R.; Prabaharan, T.; Shyam, A.

2011-11-01

420

Aluminum for plasmonics.  

PubMed

Unlike silver and gold, aluminum has material properties that enable strong plasmon resonances spanning much of the visible region of the spectrum and into the ultraviolet. This extended response, combined with its natural abundance, low cost, and amenability to manufacturing processes, makes aluminum a highly promising material for commercial applications. Fabricating Al-based nanostructures whose optical properties correspond with theoretical predictions, however, can be a challenge. In this work, the Al plasmon resonance is observed to be remarkably sensitive to the presence of oxide within the metal. For Al nanodisks, we observe that the energy of the plasmon resonance is determined by, and serves as an optical reporter of, the percentage of oxide present within the Al. This understanding paves the way toward the use of aluminum as a low-cost plasmonic material with properties and potential applications similar to those of the coinage metals. PMID:24274662

Knight, Mark W; King, Nicholas S; Liu, Lifei; Everitt, Henry O; Nordlander, Peter; Halas, Naomi J

2014-01-28

421

Ionization and expansion of barium clouds in the ionosphere  

NASA Technical Reports Server (NTRS)

A recently envelope 3D model is used here to study the motion of the barium clouds released in the ionosphere, including the ionization stage. The ionization and the expansion of the barium clouds and the interaction between the clouds and the background ions are investigated using three simulations: a cloud without a directional velocity, a cloud with an initial velocity of 5 km/s across the B field, and a cloud with initial velocity components of 2 km/s both along and across the B field.

Ma, T.-Z.; Schunk, R. W.

1993-01-01

422

Photoionization and Photoelectric Loading of Barium Ion Traps  

E-print Network

Simple and effective techniques for loading barium ions into linear Paul traps are demonstrated. Two-step photoionization of neutral barium is achieved using a weak intercombination line (6s2 1S0 6s6p 3P1, 791 nm) followed by excitation above the ionization threshold using a nitrogen gas laser (337 nm). Isotopic selectivity is achieved by using a near Doppler-free geometry for excitation of the triplet 6s6p 3P1 state. Additionally, we report a particularly simple and efficient trap loading technique that employs an in-expensive UV epoxy curing lamp to generate photoelectrons.

A. V. Steele; L. R. Churchill; P. F. Griffin; M. S. Chapman

2007-03-22

423

Methods for producing monodispersed particles of barium titanate  

DOEpatents

The present invention is a low-temperature controlled method for producing high-quality, ultrafine monodispersed nanocrystalline microsphere powders of barium titanate and other pure or composite oxide materials having particles ranging from nanosized to micronsized particles. The method of the subject invention comprises a two-stage process. The first stage produces high quality monodispersed hydrous titania microsphere particles prepared by homogeneous precipitation via dielectric tuning in alcohol-water mixed solutions of inorganic salts. Titanium tetrachloride is used as an inorganic salt precursor material. The second stage converts the pure hydrous titania microsphere particles into crystalline barium titanate microsphere powders via low-temperature, hydrothermal reactions.

Hu, Zhong-Cheng (Knoxville, TN)

2001-01-01

424

Study of the photovoltaic effect in thin film barium titanate  

NASA Technical Reports Server (NTRS)

The photoelectric effect in structures consisting of metal deposited barium titanate film silicon is described. A radio frequency sputtering technique is used to deposit ferroelectric barium titantate films on silicon and quartz. Film properties are measured and correlated with the photoelectric effect characteristics of the films. It was found that to obtain good quality pin hole free films, it is necessary to reduce the substrate temperature during the last part of the deposition. The switching ability of the device with internal applied voltage is improved when applied with a ferroelectric memory device.

Grannemann, W. W.; Dharmadhikari, V. S.

1981-01-01

425

Aluminum: Recycling Comes of Age  

NASA Astrophysics Data System (ADS)

Recycled aluminum is used by integrated producers who are capable of extracting aluminum from the ore, by non-integrated fabricators who rely on scrap for part of their production, and secondary smelters who depend entirely on scrap. Approximately 20% of the 14 billion pounds of aluminum shipped in the U.S. in 1978 came from recycled sources. Recycling aluminum requires only 5% of the energy needed to produce aluminum from the ore, and there are substantial savings in capital investment requirements. Since fabricators of aluminum products return nearly 100% of their scrap, future growth in recycled aluminum is possible largely through reclamation of post-consumer scrap. The basics of aluminum recycling are discussed, the technical and commercial problems outlined, and illustrations given of current industry activities.

Ballance, John B.

1980-02-01

426

Aluminum Hydroxide and Magnesium Hydroxide  

MedlinePLUS

Aluminum Hydroxide, Magnesium Hydroxide are antacids used together to relieve heartburn, acid indigestion, and upset stomach. They ... They combine with stomach acid and neutralize it. Aluminum Hydroxide, Magnesium Hydroxide are available without a prescription. ...

427

Photoemission study of aluminum/tris-(8-hydroxyquinoline) aluminum and aluminum/LiF/tris-(8-hydroxyquinoline) aluminum interfaces  

NASA Astrophysics Data System (ADS)

We have investigated the interfaces of aluminum on tris-(8-hydroxyquinoline) aluminum (Alq3) and aluminum on LiF/Alq3, using x-ray and ultraviolet photoemission spectroscopy (UPS). Aluminum appears to react destructively with Alq3 causing significant modification of the oxygen, nitrogen, and aluminum spectra. The well-defined UPS spectrum of Alq3 is quickly destroyed by very low coverages of aluminum. With only a 5 Å layer of LiF on the Alq3, the reaction with aluminum is significantly suppressed. The Alq3 molecular orbital features in the UPS shift to higher binding energy but remain easily recognizable. In addition, a well-defined gap-state forms which is significantly different from that produced without LiF. Both the core-level spectra and the gap-state suggest that the Alq3 anion is formed in the presence of aluminum and LiF.

Le, Quoc Toan; Yan, Li; Gao, Yongli; Mason, M. G.; Giesen, D. J.; Tang, C. W.

2000-01-01

428

Aluminum Wash and Leach Factors  

SciTech Connect

This report estimates aluminum wash and leach factors using a waste type modeling approach. The model produces reasonable aluminum wash-leach factor predictions that can be used in the Hanford Tank Waste Operations Simulator model.

MEACHAM, J.E.

2003-07-10

429

Regeneration of aluminum hydride  

DOEpatents

The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

Graetz, Jason Allan (Mastic, NY); Reilly, James J. (Bellport, NY)

2009-04-21

430

Recycled Aluminum Ornaments  

NSDL National Science Digital Library

This lesson plan from ATEEC will explain the principles of recycling. The activity would be most appropriate for technology studies or high school science classes. In all, it would require 2-5 hours of class time to complete. The purpose of the lesson is to demonstrate how aluminum is recycled. This laboratory activity does require some special equipment including a heat source capable of melting aluminum and an outdoor work area. Extension activities are also provided. The lesson plan is available for download as a PDF; users must create a free, quick login with ATEEC to access the materials.

Wishart, Ray

431

Elevated temperature aluminum alloys  

NASA Technical Reports Server (NTRS)

Three aluminum-lithium alloys are provided for high performance aircraft structures and engines. All three alloys contain 3 wt % copper, 2 wt % lithium, 1 wt % magnesium, and 0.2 wt % zirconium. Alloy 1 has no further alloying elements. Alloy 2 has the addition of 1 wt % iron and 1 wt % nickel. Alloy 3 has the addition of 1.6 wt % chromium to the shared alloy composition of the three alloys. The balance of the three alloys, except for incidentql impurities, is aluminum. These alloys have low densities and improved strengths at temperatures up to 260.degree. C. for long periods of time.

Meschter, Peter (Inventor); Lederich, Richard J. (Inventor); O'Neal, James E. (Inventor)

1989-01-01

432

Regeneration of aluminum hydride  

DOEpatents

The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, and by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

Graetz, Jason Allan; Reilly, James J; Wegrzyn, James E

2012-09-18

433

Presynaptic calcium currents at voltage-clamped excitor and inhibitor nerve terminals of crayfish.  

PubMed Central

1. A two-electrode voltage clamp was used to record calcium currents from the excitatory and inhibitory nerve terminals that innervate the crayfish (Procambarus spp.) opener muscle. Other voltage-dependent currents were blocked with tetrodotoxin, 3,4-diaminopyridine, 4-aminopyridine and tetraethylammonium. 2. The presynaptic calcium current at both excitatory and inhibitory synapses was blocked by cadmium and omega-agatoxin IVA but was not affected by omega-conotoxin GVIA, omega-conotoxin MVIIC or nifedipine, suggesting that the calcium currents flow through P-type calcium channels. 3. Current-voltage (I-V) relations at both excitatory and inhibitory synapses are similar, with current activation near -40 mV, peak current near -10 mV and current reversal at membrane potentials greater than +25 mV. I-V relations were scaled along the current axis by partial calcium current blockade with cobalt, suggesting that series resistance and space-clamp errors were small. 4. A subset of terminals on one muscle fibre was locally superfused with a physiological saline containing barium; the rest of the preparation was superfused with a physiological saline containing calcium channel antagonists. Under such conditions the characteristics of the I-V relation were very similar to the I-V relations recorded when the entire preparation was bathed in physiological levels of calcium, suggesting that the space clamp was adequate. 5. Calcium channel activation, as determined from tail current analyses, was similar when the entire preparation was bathed in physiological levels of calcium or if terminals on one muscle fibre were locally superfused with barium. 6. During a 30 ms depolarization, calcium currents inactivated to a greater extent in inhibitory than in excitatory terminals. The inactivation was of small magnitude (< 20%) and was eliminated by intracellular injection of the calcium chelator BAPTA, suggesting that the inactivation was calcium dependent. 7. These data show that biophysical and pharmacological properties of calcium currents at crayfish neuromuscular junctions resemble those found at stellate synapses in squid. Images Figure 5 PMID:8910221

Wright, S N; Brodwick, M S; Bittner, G D

1996-01-01

434

Molecular Structure of Aluminum Fluoride  

NSDL National Science Digital Library

Aluminum Fluoride is a solid, off-white, free-flowing granular material, insoluble in most organic and inorganic liquids at room temperatures. It is soluble in many fused salts. Aluminum Fluoride is used by aluminum producers to increase the conductivity of electrolytes in the smelting process. It is used as a flux ingredient for the removal of magnesium in refining aluminum scrap, by the ceramic industry for some body and glazing mixtures, and in the production of specialty refractory products.

2003-06-02

435

Membrane Purification Cell for Aluminum Recycling  

Microsoft Academic Search

Recycling mixed aluminum scrap usually requires adding primary aluminum to the scrap stream as a diluent to reduce the concentration of non-aluminum constituents used in aluminum alloys. Since primary aluminum production requires approximately 10 times more energy than melting scrap, the bulk of the energy and carbon dioxide emissions for recycling are associated with using primary aluminum as a diluent.

David DeYoung; James Wiswall; Cong Wang

2011-01-01

436

Electrically conductive anodized aluminum coatings  

NASA Technical Reports Server (NTRS)

A process for producing anodized aluminum with enhanced electrical conductivity, comprising anodic oxidation of aluminum alloy substrate, electrolytic deposition of a small amount of metal into the pores of the anodized aluminum, and electrolytic anodic deposition of an electrically conductive oxide, including manganese dioxide, into the pores containing the metal deposit; and the product produced by the process.

Alwitt, Robert S. (Inventor); Liu, Yanming (Inventor)

2001-01-01

437

RECLAMATION OF ALUMINUM FINISHING SLUDGES  

EPA Science Inventory

The research study of the reclamation of aluminum-anodizing sludges was conducted in two sequential phases focused on enhanced dewatering of aluminum-anodizing sludges to produce commercial-strength solutions of aluminum sulfate, i.e., liquid alum. The use of high-pressure (14 to...

438

Aluminum battery alloys  

DOEpatents

Aluminum alloys suitable for use as anode structures in electrochemical cells are disclosed. These alloys include iron levels higher than previously felt possible, due to the presence of controlled amounts of manganese, with possible additions of magnesium and controlled amounts of gallium.

Thompson, D.S.; Scott, D.H.

1984-09-28

439

Aluminum battery alloys  

DOEpatents

Aluminum alloys suitable for use as anode structures in electrochemical cs are disclosed. These alloys include iron levels higher than previously felt possible, due to the presence of controlled amounts of manganese, with possible additions of magnesium and controlled amounts of gallium.

Thompson, David S. (Richmond, VA); Scott, Darwin H. (Mechanicsville, VA)

1985-01-01

440

Aluminum Sulfate 18 Hydrate  

ERIC Educational Resources Information Center

A chemical laboratory information profile (CLIP) of the chemical, aluminum sulfate 18 hydrate, is presented. The profile lists physical and harmful properties, exposure limits, reactivity risks, and symptoms of major exposure for the benefit of teachers and students using the chemical in the laboratory.

Young, Jay A.

2004-01-01

441

Maize aluminum tolerance  

Technology Transfer Automated Retrieval System (TEKTRAN)

Maize is one of the most economically important food crops grown on acid soils, where aluminum (Al) toxicity greatly limits crop yields. Considerable variation for Al tolerance exists in maize, and this variation has been exploited for many years by plant breeders to enhance maize Al tolerance. Curr...

442

Aluminum Corrosion and Turbidity  

SciTech Connect

Aluminum corrosion and turbidity formation in reactors correlate with fuel sheath temperature. To further substantiate this correlation, discharged fuel elements from R-3, P-2 and K-2 cycles were examined for extent of corrosion and evidence of breaking off of the oxide film. This report discusses this study.

Longtin, F.B.

2003-03-10

443

Interactions of Silicate Ions with Zinc(II) and Aluminum(III) in Alkaline Aqueous Solution  

E-print Network

with the release of silicate and calcium ions into the physiological environment, which becomes permanentlyInteractions of Silicate Ions with Zinc(II) and Aluminum(III) in Alkaline Aqueous Solution Michel R 16, 2005 We present 29 Si, 27 Al, and 67 Zn NMR evidence to show that silicate ions in alkaline

Sahai, Nita

444

Residual aluminum oxide on the surface of titanium implants has no effect on osseointegration  

Microsoft Academic Search

The cleanliness of titanium dental implants surfaces is considered to be an important requirement for achieving osseointegration, and it has been hypothesized that the presence of inorganic contaminants could lead to lack of clinical success. Aluminum ions are suspected to impair bone formation by a possible competitive action to calcium. The objective of the present study was to describe the

Adriano Piattelli; Marco Degidi; Michele Paolantonio; Carlo Mangano; Antonio Scarano

2003-01-01

445

Voltage dependence of two inward currents carried by calcium and barium in the ciliate Stylonychia mytilus.  

PubMed Central

Two voltage-dependent inward currents in the fresh-water hypotrichous ciliate Stylonychia mytilus have been investigated, using two intracellular micro-electrodes, when either Ca ions or Ba ions are the charge carriers. In cells bathed in Ca-free Ba solution the two inward currents, named current I and current II, could be identified and studied in the absence of outward currents. The two inward currents could also be separated by addition of the plant lectin concanavalin A (0.5 microgram/ml) to the external medium, which resulted in the selective inhibition of current I. When the holding potential was set at values between -45 and -65 mV (normal resting potential is -50 mV), current I was shifted parallel to the holding potential along the voltage axis. This shift was 7.6 mV per 10 mV change in holding potential. The amplitude and voltage relationship of current II was not affected by these changes in the holding potential. The amplitude of current I in Ba solution was maximal when the membrane potential was held at -55 mV; it decreased with higher and lower holding potentials. The rate of activation of current I remained virtually unaffected at holding potentials between -45 and -60 mV, and was somewhat reduced at a holding potential of -65 mV. When the extracellular Ca concentration was varied between 0.1 and 5.0 mM, or when the cells were loaded with EGTA to reduce the intracellular level of ionized Ca, the resting membrane potential and the voltage relationships of both current I and II and of the outward current were shifted along the voltage axis according to the expected changes in membrane surface potential. Double-pulse experiments with varying interval potentials suggested voltage-dependent inactivation of current I and Ca-dependent inactivation of current II. Pre-hyperpolarizing steps of only 1 mV amplitude and 30 ms duration could result in the activation of current I, indicating that the activation voltage of current I closely followed the actual membrane potential. Hence, the same voltage steps elicited similar current I amplitudes with holding potentials between -45 and -60 mV. The results indicate that current II displays voltage properties described for Ca channels in other ciliates and many multicellular preparations, while current I shows an unusual voltage behaviour, which might be regarded as an 'adaptive type of excitation'.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2441038

Deitmer, J W

1986-01-01

446

Potassium blocks barium permeation through a calcium-activated potassium channel  

Microsoft Academic Search

Single high-conductance Ca2+-activated K + channels from rat skeletal muscle were inserted into planar lipid bilayers, and discrete blocking by the Ba 2+ ion was studied. Specifically, the ability of external K § to reduce the Ba ~+ dissocia- tion rate was investigated. In the presence of 150 mM internal K +, 1-5 #M inter- nal Ba z+, and 150

JACQUES NEYTON; CHRISTOPHER MILLER

1988-01-01

447

Straczekite, a new calcium barium potassium vanadate mineral from Wilson Springs, Arkansas.  

USGS Publications Warehouse

Straczekite occurs as a rare secondary mineral in fibrous seams, along with other V minerals (A.M. 64-713), in ore from the vanadium mine in Wilson Springs (formerly Potash Sulfur Springs), Garland County, Arkansas. It forms soft, thin laths of dark greenish black crystals up to 0.5 mm in length. Indexed XRD data are tabulated; strongest lines 3.486(100), 10.449(50), 1.8306(50), 1.9437(15) A; a 11.679, b 3.6608, c 10.636 A, beta 100.53o; space group C2/m, C2 or Cm. Chemical analysis gave V2O5 66.4, V2O4 15.3, Fe2O3 0.9, Na2O 0.4, K2O 1.8, CaO 2.5, BaO 5.5, H2O 7.2, = 100.0, leading to the formula (Ca0.39Ba0.31K0.33Na0.11)- 196(V4+1.59V5+6.31Fe3+0.10)O20.02(H2O)2.9; Dcalc. 3.21 g/cm3. A possible layer structure is discussed. The name is for J. A. Straczek, Chief Geologist at Union Carbide Corp.-R.A.H.

Evans, H.T., Jr.; Nord, G.; Marinenko, J.; Milton, C.

1984-01-01

448

Results of critical velocity experiments with barium, strontium, and calcium releases from CRRES satellite  

NASA Technical Reports Server (NTRS)

As part of the NASA Combined Release and Radiation Effects Satellite (CRRES) chemical release program in September 1990, two Ba and also one each Sr and Ca canisters of a boron-titanium thermite mixture, which vaporizes the element on ignition, were released near perigee after dusk in the South Pacific to study the critical velocity effect proposed by Alfven. The critical velocities of these three elements are 2.7, 3.5, and 5.4 km/s respectively, all well below the orbital velocity of 9.4 km/s. On September 10, 1990, a Sr and Ba pair (G-13, or critical ionization velocity (CIV) I) was released near Rarotonga at approximately 515 km altitude in a background electron density of 3.4 x 10(exp 6)/cu cm. On September 14, 1990, G-14 or CIV II released a Ca and Ba pair west of New Caledonia near 595 km at an electron density of 1.5 x 10(exp 6)/cu cm. Ions of all three elements were observed with low-light level imagers from two aircraft after they had transited up the magnetic field lines into the sunlight. Emissions from the spherically expanding neutral gas shells below the solar terminator, observed with cameras filtered for the Ba(+) ion line at 4554 A and also in unfiltered imagers for approximately 15 s after release, are probably due to excitation by hot electrons created in the CIV process. The ions created clearly lost much of their energy, which we now show can be explained by elastic collisions: Ba(+) + O. Inventories of the observed ions indicate yields of 0.15% and 1.84% for Ba in the first and second experiments, 0.02% for Sr and 0.27% for Ca. Ionization from all the releases continued along the satellite trajectory much longer (greater than 45 s) than expected for a CIV process. The ion production along the satellite track versus time typically shows a rapid rise to a peak in a few seconds followed by an exponential decrease to a level essentially constant rate. The characteristic distances for CIV I and II are 47 and 62 km, respectively. We interpret the early time rise and exponential fall to be due to CIV ionization, of 0.014% (CIV I) and 0.40% (CIV II) for the Ba releases. The later ions produced at a constant rate probably have origins from other such processes as stripping and associative ionization collisions with atmospheric constituents primarily O, and charge exchange with O(+), He(+), and H(+). We suggest that the much larger Ba ionization rate in CIV II than CIV I is due to the fact that the release occurred in the peak Ca density where hot electrons were already present.

Wescott, E. M.; Stenbaek-Nielsen, H. C.; Hampton, D. L.; Delamere, P. A.

1994-01-01

449

Study of barium feldspar polymorphism as a function of temperature and calcium content  

Microsoft Academic Search

A family of new glass-ceramic materials, of the general formula (25-x)CaO·xBaO·yMgO· zAl2O3·50SiO2, where x = 1, 2, 5, 10, 15, 20, 25, y = 20 or 14 and z = 5 or 11 (mol%), has been prepared by melting raw materials in two parent glasses and performing heat treatments. The systematic substitution of BaO for CaO in the base glasses

L. Barbieri; A. Bonamartini Corradi; C. Leonelli; T. Manfredini; G. C. Pellacani

1995-01-01

450

Synthesis and surface properties of submicron barium sulfate particles  

NASA Astrophysics Data System (ADS)

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO 4 particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO 4 particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO 4 were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO 4 was presented. The FTIR result indicates that the surface of the prepared BaSO 4 absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

Zhang, Ming; Zhang, Bao; Li, Xinhai; Yin, Zhoulan; Guo, Xueyi

2011-10-01

451

Original article Response to barium selenate supplementation in sheep  

E-print Network

group did not receive any supplement of Se and/or vitamin E. The two groups were managed under the sameOriginal article Response to barium selenate supplementation in sheep kept at pasture supplements in the prevention of dis- orders related to Se deficiency in sheep maintained at pasture

Boyer, Edmond

452

BARIUM AND RADIUM IN WATER TREATMENT PLANT WASTES  

EPA Science Inventory

Water treatment plants at nine locations (10 plants) in Illinois and Iowa were studied to determine the characteristics and disposal practices for the sludge, brine, and backwash water containing radium (Ra) and/or barium (Ba). The treatment processes in these ten plants include ...

453

Magnetic and structural characteristics of sputtered barium ferrite thin films  

Microsoft Academic Search

? M curves have been measured on both randomly and perpendicularly oriented barium ferrite thin films. Compared with theoretical simulations, the shape and peak values of the ? M curves suggest that the intergranular exchange interaction in sputtered BaM thin films is negligible. This is similar to the case of oxide particulate media even though the sputtered films are much

Jinshan Li; Stephen S. Rosenbluem; Hidetaka Hayashi; Robert Sinclair

1996-01-01

454

Structure and magnetic properties of aerosol synthesized barium ferrite particles  

Microsoft Academic Search

The aerosol synthesis technique has been employed to produce barium ferrite particles. X-ray and electron diffraction, scanning and transmission microscopy methods were used to find detailed information on crystallography, morphology and chemical composition of as prepared and annealed powders. A detailed study has been made of the correlation between magnetic hysteresis parameters and the inner structure of submicrometer ferrite particles.

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

1991-01-01

455

BARIUM AND RADIUM REMOVAL FROM GROUNDWATER BY ION EXCHANGE  

EPA Science Inventory

The primary objective of this study was to determine the applicability of weak acid exchange resin in the hydrogen form for removal of hardness, barium and radium from groundwater. Weak acid resin in the hydrogen form eliminates the addition of sodium to drinking water. The capac...

456

Long Term Magnetic Stability of Alnico and Barium Ferrite Magnets  

Microsoft Academic Search

Alnico and barium ferrite materials do not age at room temperature. The decreases in remanence, occurring with time, are adjustments by the magnet to its environment. Remanence adjustment proceeds with the logarithm of time and amounts to 2% or less one year after magnetization. Remanences in magnets with Hci > 2200 oe show no changes. Also, the smaller the irreversible

K. J. Kronenberg; M. A. Bohlmann

1960-01-01

457

Dynamics of a barium release in the magnetospheric tail  

NASA Technical Reports Server (NTRS)

The late time behavior of the May 13, 1985 magnetotail barium cloud is examined. The bulk dynamics of the cloud are studied based on triangulated data and data from Fabry-Perot Doppler velocity measurements. The changes in cloud morphology in relation to the in situ measurements made by the Ion Release Module satellite are discussed.

Mende, S. B.; Swenson, G. R.; Geller, S. P.; Doolittle, J. H.; Haerendel, G.

1989-01-01

458

PROPOSED ORAL REFERENCE DOSE (RFD) FOR BARIUM AND COMPOUNDS  

EPA Science Inventory

The Integrated Risk Information System (IRIS) is a database of EPA's consensus opinion of the human health effects that may result from exposure to various substances found in the environment. A Toxicological Review and IRIS Summary were prepared for barium and compounds in 1998 ...

459

Electron Optical Studies of Barium Titanate Single Crystal Films  

Microsoft Academic Search

Thin single crystal films of barium titanate prepared by chemical thinning of single crystal plates are studied by transmission electron microscopy and electron diffraction. The films as thin as 1000 Å are found to have the same lattice parameters as the bulk crystals, giving no evidence for the existence of the anomalous surface layer proposed by Känzig et al. The

Michiyoshi Tanaka; Goro Honjo

1964-01-01

460

Nanoshell tubes of ferroelectric lead zirconate titanate and barium titanate  

Microsoft Academic Search

Wafer-scale fabrication of ferroelectric oxide nanoshell tubes as well as ordered nanotube arrays have been accomplished using a simple and convenient fabrication method that allows full tailoring of tube dimensions as well as array pattern and size. Using different silicon and alumina templates, barium titanate and lead zirconate titanate tubes with diameters ranging from 50 nm up to several micrometers

Yun Luo; Izabela Szafraniak; Nikolai D. Zakharov; Valanoor Nagarajan; Martin Steinhart; Ralf B. Wehrspohn; Joachim H. Wendorff; Ramamoorthy Ramesh; Marin Alexe

2003-01-01

461

Hierarchical Structure-Ferroelectricity Relationships of Barium Titanate Particles  

E-print Network

Review Hierarchical Structure-Ferroelectricity Relationships of Barium Titanate Particles Tu Lee structural levels and to thoroughly review the corresponding structure- ferroelectricity relationships at all). However, the inconsistency of the critical size in the literature, ranging from 15 to 200 nm in diameter,4

Aksay, Ilhan A.

462

Kinetics and mechanisms of hydrothermal synthesis of barium titanate  

SciTech Connect

Reaction mechanisms for the hydrothermal synthesis of barium titanate are evaluated. Feedstocks of barium hydroxide octahydrate and anatase titania are reacted for varying durations (1--72 h) to provide intermediate-stage samples for characterization by transmission electron microscopy/energy-dispersive spectroscopy (TEM/EDS), X-ray diffractometry (XRD), and inductively coupled plasma spectroscopy (ICP) and XRD methods permits the analysis of data with the Johnson-Mehl-Avrami equation. This analysis reveals two reaction-rate regimes. Kinetic analysis, based on reaction progress, yields insight into the first reaction-rate regime but is inconclusive in the analysis of the second reaction-rate regime. In the first regime, at the early stage of barium titanate formation, a dissolution-precipitation mechanism dominates. In contrast, in the second regime, at longer reaction times, an in-situ transformation mechanism is probably dominant. However, multiple reaction mechanisms (e.g., in-situ transformation and dissolution-precipitation) may be competing for rate control. Alternatively, dissolution-precipitation may be the dominant mechanism throughout the barium titanate synthesis, with nucleation and growth controlling the first regime and dissolution rate controlling the second regime.

Eckert, J.O. Jr.; Hung-Houston, C.C.; Gersten, B.L.; Lencka, M.M.; Riman, R.E. [Rutgers Univ., Piscataway, NJ (United States). Dept. of Ceramics

1996-11-01

463

Alkoxylation using modified calcium-containing bimetallic or polymetallic catalysts  

SciTech Connect

This patent describes a method for providing an alkoxylation catalyst. It comprises reacting or solubilizing, at least partially, calcium metal or a calcium-containing compound, by mixing with an activator or solubilizing thereby forming a calcium-containing reacting a divalent or polyvalent metal or a divalent or polyvalent metal-containing compound wherein the divalent or polyvalent metal is selected from the group consisting of beryllium, magnesium, strontium, barium, lanthanum, titanium, zirconium, hafnium, niobium, tantalum, molybdenum, tungsten, iron, cobalt, nickel, copper, zinc, boron, gallium, silicon, germanium tin, phosphorus, antimony, sulfur, selenium, tellurium, cerium and thorium with an organic compound having at least one active hydrogen to produce a divalent or polyvalent metal-containing composition: reacting the calcium-containing composition with the divalent or polyvalent metal-containing composition under effective reaction conditions to produce a catalyst precursor composition; and reacting the catalyst precursor composition with a divalent or polyvalent oxyacid or a divalent or polyvalent metal salt of an oxyacid or mixtures thereof under effective reaction conditions to produce the alkoxylation catalyst.

King, S.W.

1992-05-19

464

Calcium is incorporated into the calcium carbonate matrix of otoliths  

E-print Network

118 Calcium is incorporated into the calcium carbonate matrix of otoliths and into the calcium). In addition to calcium, trace elements, such as strontium, are also incorporated into the calcified components valence) allow strontium ions to act as replace- ments for calcium during the pro- cess of calcification

465

Preliminary study of the CRRES magnetospheric barium releases  

NASA Technical Reports Server (NTRS)

Preliminary theoretical and computational analyses of the Combined Release and Radiation Effects Satellite (CRRES) magnetospheric barium releases are presented. The focus of the studies is on the evolution of the diamagnetic cavity which is formed by the barium ions as they expand outward, and on the structuring of the density and magnetic field during the expansion phase of the releases. Two sets of simulation studies are discussed. The first set is based upon a 2D ideal MHD code and provides estimates of the time and length scales associated with the formation and collapse of the diamagnetic cavity. The second set uses a nonideal MHD code; specifically, the Hall term is included. This additional term is critical to the dynamics of sub-Alfvenic plasma expansions, such as the CRRES barium releases, because it leads to instability of the expanding plasma. Detailed simulations of the G4 and G10 releases were performed. In both cases the expanding plasma rapidly structured: the G4 release structured at time t less than about 3 s and developed scale sizes of about 1-2 km, while the G10 release structured at time t less than about 22 s and developed scale sizes of about 10-15 km. It is also found that the diamagnetic cavity size is reduced from those obtained from the ideal MHD results because of the structure. On the other hand, the structuring allows the formation of plasma blobs which appear to free stream across the magnetic field; thus, the barium plasma can propagate to larger distances traverse to the magnetic field than the case where no structuring occurs. Finally, a new normal mode of the system was discovered which may be excited at the leading edge of the expanding barium plasma.

Huba, J. D.; Bernhardt, P. A.; Lyon, J. G.

1992-01-01

466

Production of niobium powder by electronically mediated reaction (EMR) using calcium as a reductant  

Microsoft Academic Search

Explored in this study is an electronically mediated reaction (EMR) route for the production of niobium powder using calcium as a reductant for niobium oxide (Nb2O5). Feed material, Nb2O5, and reductant calcium alloy containing aluminum and nickel were charged into electronically isolated locations in a molten salt (e.g. CaCl2) at 1173 K. The current flow through an external path between

Toru H. Okabe; Il Park; K. T. Jacob; Yoshio Waseda

1999-01-01

467

ALUMINUM SOLUBILITY, CALCIUM-ALUMINUM EXCHANGE, AND PH IN ACID FOREST SOILS  

EPA Science Inventory

Important components in several models designed to describe the effects of acid deposition on soils and surface waters are the pH-A1 and Ca-A1 exchange relationships. f A1 solubility is controlled by A1 trihydroxide minerals, the theoretical pH-A1 relationship can be described by...

468

Complete elimination of acid injection in reverse osmosis plants  

Microsoft Academic Search

Antiscalants with broad activity spectra are available today. When properly chosen, a single antiscalant can efficiently and simultaneously control calcium carbonate, calcium sulfate, strontium sulfate, barium sulfate and calcium fluoride scales as well as inorganic foulants resulting from iron, aluminum and reactive silica present in any given water or wastewater. The effectiveness of many antiscalants towards controlling calcium carbonate scaling

Robert Y. Ning; Jeffrey P. Netwig

2002-01-01

469

Direct acid dissolution of aluminum and other metals from fly ash  

SciTech Connect

Fly ash could provide a significant domestic source of alumina and thus supply a large part of the US needs for aluminum and possibly also several other metals. The aluminum and other metals can be solubilized from fly ash by acid dissolution methods. The aluminum may be present in any or all of three solid phases: (1) crystalline; (2) glassy amorphous; and (3) irregular, spongy amorphous. The chemistry of these phases controls the solubilization behavior. The aluminum in high-calcium western ashes is primarily found in the amorphous phases, and much of it can be solubilized by using short-time, ambient-temperature leaching. Little of the aluminum in the low-calcium eastern ashes is solubilized under ambient-temperature conditions, and only a portion can be solubilized even at reflux temperature conditions. Some of the aluminum in these eastern ashes is present as mullite, while some is found in the amorphous material. The fraction contained in mullite is relativey acid insoluble, and only partial solubilization can be achieved even under vigorous acid leach conditions.

Kelmers, A.D.; Egan, B.Z.; Seeley, F.G.; Campbell, G.D.

1981-01-01

470

21 CFR 82.2051 - Lakes (Ext. D&C).  

Code of Federal Regulations, 2010 CFR

...hereinbefore listed in this subpart by combining such color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2) Specifications. Ether extracts, not more than 0.5 percent. Soluble chlorides and...

2010-04-01

471

Improved cryogenic aluminum mirrors  

NASA Astrophysics Data System (ADS)

Optical surface deformation of metal mirrors used at cryogenic temperatures is reduced through the use of a new process of plating amorphous aluminum on aluminum. The AlumiPlateTM process (produced by AlumiPlate, Inc. in Minneapolis, MN) plates a layer of 99.9+% high purity aluminum about 125 micrometers thick atop the substrate. Very good surface finishes are produced by direct diamond turning of the plating, with some samples below 40 angstroms RMS. Optical testing of a 175-mm diameter, 550-mm optical radius of curvature 6061-T651/AlumiPlateTM aluminum sphere was performed at 65 K to determine cryogenic optical surface figure stability. In five cycles from 300 to 65 K, an average optical surface change of 0.047 wave RMS (1 wave equals 633 nm) was observed. A total optical figure change of 0.03 wave RMS at 65 K was observed from the first to last cycle. The cause of this relatively small long-term change is not yet determined. The test mirror is bi-concave, with a semi- kinematic toroidal mount, and is machined from the axis of a billet. An `uphill quench' heat treatment consisting of five cycles from liquid nitrogen to boiling water temperatures is used to minimize residual stress in the test mirror. Initial diamond turning of the mirror by the Optical Filter Corp., Keene, NH, produced a 300 K unmounted optical surface figure of 0.380 wave peak-to-valley and 0.059 wave RMS. A second effort at diamond turning by II-VI, Inc., Saxonburg, PA produced a 300 K optical figure of 0.443 wave peak-to-valley and 0.066 wave RMS, with a surface roughness varying from 29 to 42 angstroms.

Vukobratovich, Daniel; Don, Ken; Sumner, Richard E.

1998-09-01

472

Interactions between chloride and sulfate or silica removals from wastewater using an advanced lime-aluminum softening process: equilibrium modeling.  

PubMed

Interactions among chloride, sulfate, and silica removals from recycled industrial wastewater using an ultra-high lime with aluminum process (UHLA) were studied. An equilibrium model that is able to accurately predict the chemical behavior and interactions between chloride and sulfate or silica with UHLA at various initial conditions and chemical reagents was developed. X-ray diffraction (XRD) analysis was conducted to identify the precipitated solids formed in the UHLA process. Model predictions indicated that simultaneous removal of sulfate and chloride can be best described by the formation of a solid solution containing calcium chloroaluminate, calcium sulfoaluminate (ettringite), calcium monosulfate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. However, simultaneous removal of silica and chloride can be best described by precipitation of calcium silicate and calcium aluminosilicate in addition to a solid solution containing calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. The XRD results indicated the presence of the same solids assumed by the equilibrium model. PMID:17571843

Abdel-Wahab, Ahmed; Batchelor, Bill

2007-05-01

473

Design, testing, fabrication and launch support of a liquid chemical barium release payload (utilizing the liquid fluorine-barium salt/hydrazine system)  

NASA Technical Reports Server (NTRS)

A payload was designed which included a cryogenic oxidizer tank, a fuel tank, and burner section. Release of 30 lb of chemicals was planned to occur in 2 seconds at the optimum oxidizer to fuel ratio. The chemicals consisted of 17 lb of liquid fluorine oxidizer and 13 lb of hydrazine-barium salt fuel mixture. The fuel mixture was 17% barium chloride, 16% barium nitrate, and 67% hydrazine, and contained 2.6 lb of available barium. Two significant problem areas were resolved during the program: explosive valve development and burner operation. The release payload was flight tested, from Wallops Island, Virginia. The release took place at an altitude of approximately 260 km. The release produced a luminous cloud which expanded very rapidly, disappearing to the human eye in about 20 seconds. Barium ion concentration slowly increased over a wide area of sky until measurements were discontinued at sunrise (about 30 minutes).

Stokes, C. S.; Smith, E. W.; Murphy, W. J.

1972-01-01

474

Aluminum Carbothermic Technology  

SciTech Connect

This report documents the non-proprietary research and development conducted on the Aluminum Carbothermic Technology (ACT) project from contract inception on July 01, 2000 to termination on December 31, 2004. The objectives of the program were to demonstrate the technical and economic feasibility of a new carbothermic process for producing commercial grade aluminum, designated as the ''Advanced Reactor Process'' (ARP). The scope of the program ranged from fundamental research through small scale laboratory experiments (65 kW power input) to larger scale test modules at up to 1600 kW power input. The tasks included work on four components of the process, Stages 1 and 2 of the reactor, vapor recovery and metal alloy decarbonization; development of computer models; and economic analyses of capital and operating costs. Justification for developing a new, carbothermic route to aluminum production is defined by the potential benefits in reduced energy, lower costs and more favorable environmental characteristics than the conventional Hall-Heroult process presently used by the industry. The estimated metrics for these advantages include energy rates at approximately 10 kWh/kg Al (versus over 13 kWh/kg Al for Hall-Heroult), capital costs as low as $1250 per MTY (versus 4,000 per MTY for Hall-Heroult), operating cost reductions of over 10%, and up to 37% reduction in CO2 emissions for fossil-fuel power plants. Realization of these benefits would be critical to sustaining the US aluminum industries position as a global leader in primary aluminum production. One very attractive incentive for ARP is its perceived ability to cost effectively produce metal over a range of smelter sizes, not feasible for Hall-Heroult plants which must be large, 240,000 TPY or more, to be economical. Lower capacity stand alone carbothermic smelters could be utilized to supply molten metal at fabrication facilities similar to the mini-mill concept employed by the steel industry. Major accomplishments for the program include definition of the system thermo-chemistry, demonstration of reactor stage 1, development of reactor stage 2 critical components in a 500 kW module, experimental determination of the vapor recovery reactor fundamentals, detailed design and installation of an advanced stage 1/vapor recovery reactor, feasibility of efficient separation of Al-C metal alloy product, updated capital and operating cost estimates, and development of computer models for all steps of the Advanced Reactor Process.

Bruno, Marshall J.

2005-03-31

475

Calcium Flux During Hemodialysis  

Microsoft Academic Search

A system of equations has been derived, and examined, to describe membrane permeability and calcium fluxes within a commonly used hemodialyzer, the Mini-Kiil. By a statistical technique of sequential multiple regression analysis, factors which might influence these variables were tested on data derived from 74 hemodialysis periods in 5 patients. Calcium flux from plasma to dialysate was influenced positively by

Ralph S. Goldsmith; Jacob Furszyfer; William J. Johnson; William F. Taylor

1978-01-01

476

Disorders of Calcium Metabolism  

Microsoft Academic Search

The genetic contribution to calcium metabolism is well recognized. Many of the proteins that contribute to calcium homeostasis through intestinal absorption, bone deposition and resorption, renal reabsorption and the molecules regulating these processes have been identified. Mutations in many of the genes coding for these proteins have been identified and often have clear clinical phenotypes. These mutations are generally rare

John F. O’Toole

2011-01-01

477

Calcium Nutrition in Adolescence  

Microsoft Academic Search

Adolescence is an important period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. Calcium needs are elevated as a result of the intensive bone and muscular development and thus adequate calcium intake during growth is extremely important to reach the optimum peak bone mass and to protect against osteoporosis in the adult

Marta Mesías; Isabel Seiquer; M. Pilar Navarro

2011-01-01

478

Molecular aspects of aluminum toxicity  

Microsoft Academic Search

The focus in this review is directed to molecular aspects of aluminum toxicity in animal and plant cells. Unique thermodynamic features of Al(lII) ions impart biological specificity which may form the biochemical basis of aluminum interactions with cellular constituents. Current knowledge about aluminum?specific, molecular interactions is rather scanty. Al(III) ions may coordinate with nucleotides or complex to phospholipids resulting in

Alfred Haug; Charles E. Foy

1984-01-01

479

Fabrication of aluminum based nanomaterials  

Microsoft Academic Search

Structural applications in transportation necessitate materials with high specific strength and stiffness. With its low density, aluminum (Al) is an interesting candidate, but further strengthening would be beneficial. In this work, the benefits and limitations of nanoreinforcements for aluminum strengthening has been assessed through the addition of carbon nanotube (CNTs) and nanometric alumina (n-Al2O3) to an aluminum matrix by powder

Dominique Poirier

2009-01-01

480

Hydration of Portland cement with additions of calcium sulfoaluminates  

SciTech Connect

The effect of mineral additions based on calcium aluminates on the hydration mechanism of ordinary Portland cement (OPC) was investigated using isothermal calorimetry, thermal analysis, X-ray diffraction, scanning electron microscopy, solid state nuclear magnetic resonance and pore solution analysis. Results show that the addition of a calcium sulfoaluminate cement (CSA) to the OPC does not affect the hydration mechanism of alite but controls the aluminate dissolution. In the second blend investigated, a rapid setting cement, the amorphous calcium aluminate reacts very fast to ettringite. The release of aluminum ions strongly retards the hydration of alite but the C-S-H has a similar composition as in OPC with no additional Al to Si substitution. As in CSA-OPC, the aluminate hydration is controlled by the availability of sulfates. The coupling of thermodynamic modeling with the kinetic equations predicts the amount of hydrates and pore solution compositions as a function of time and validates the model in these systems.

Le Saout, Gwenn, E-mail: gwenn.le-saout@mines-ales.fr [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Lothenbach, Barbara [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Hori, Akihiro [DENKA Chemicals GmbH, Wehrhahn-Center, Cantadorstr. 3, D-40211 Duesseldorf (Germany)] [DENKA Chemicals GmbH, Wehrhahn-Center, Cantadorstr. 3, D-40211 Duesseldorf (Germany); Higuchi, Takayuki [Denki Kagaku Kogyo Kabushiki Kaisha (DENKA), Omi, Itoigawa, Niigata, 949-0393 (Japan)] [Denki Kagaku Kogyo Kabushiki Kaisha (DENKA), Omi, Itoigawa, Niigata, 949-0393 (Japan); Winnefeld, Frank [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland)] [Empa, Swiss Federal Laboratories for Materials Science and Technology, Concrete and Construction Chemistry Laboratory, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland)

2013-01-15

481

Vanadium doped barium germanate microrods and photocatalytic properties under solar light  

NASA Astrophysics Data System (ADS)

Vanadium doped barium germanate microrods have been prepared by a facile hydrothermal process. The obtained vanadium doped barium germanate microrods are proved to be hexagonal BaGe4O9 and orthorhombic Ba2V2O7 phases by X-ray diffraction. Scanning electron microscopy shows that the vanadium doped barium germanate products consist of microrods with the diameter of microscale size. The diameter of the mirorods decreases from 800 nm to 150 nm with the vanadium doping mass percentage increasing from 1% to 10%. Solid UV-vis diffuse reflectance spectra show that the band gap of the vanadium doped barium germanate is smaller than that of the undoped barium germanate. The photocatalytic activity has been greatly enhanced by the vanadium doping. The vanadium doped barium germanate microrods exhibit great application potential for the photocatalytic degradation of methylene blue under solar light irradiation.

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

2015-01-01

482

Barium and Yttrium abundance in intermediate-age and old open clusters  

E-print Network

Barium is a neutron capture element, that, in open clusters, is frequently over-abundant with respect to the Iron. A clear explanation for this is still missing. Additionally, its gradient across the Galactic disk is poorly constrained. We measure the abundance of yttrium and barium using the synthetic spectrum method from UVES high-resolution spectra of eight distant open clusters, namely Ruprecht 4, Ruprecht 7, Berkeley 25, Berkeley 73, Berkeley 75, NGC 6192, NGC 6404, and NGC 6583. The barium abundance was estimated using NLTE approximation. We confirm that Barium is indeed over-abundant in most clusters, especially young clusters. Finally, we investigated the trend of yttrium and barium abundances as a function of distance in the Galaxy and ages. Several scenarios for the barium over-abundance are then discussed.

Mishenina, T; Carraro, G; Kovtyukh, V V; Yegorova, I A

2013-01-01

483

Polymerized complex route to barium titanate powders using barium-titanium mixed-metal citric acid complex  

SciTech Connect

Barium titanate (BaTiO{sub 3}) powders were prepared by a polymerized complex method based on the Pechini-type reaction route, wherein a mixed solution of citric acid (CA), ethylene glycol (EG), and barium and titanium ions, with a molar ratio of CA:EG:Ba:Ti = 10:40:1:1, was polymerized to form a transparent resin, which was used as a precursor for BaTiO{sub 3}. Characterization of the initial precursor solution of EG, CA, and barium and titanium ions by Raman scattering and {sup 13}C-NMR spectroscopy indicated that barium and titanium ions were simultaneously stabilized with CA to form a barium-titanium mixed-metal CA complex with a stoichiometry similar to Ba:Ti:CA = 1:1:3. Raman and {sup 13}C-NMR spectra of the liquid mixture at various reaction stages indicated that the fundamental coordination structure of the mixed-metal complex remained almost unchanged throughout the polymerization process. X-ray diffractometry (XRD) measurements indicated formation of pseudo-cubic BaTiO{sub 3} free from BaCo, and TiO{sub 2} when the barium-titanium polymeric precursor was heat-treated in air at 500 C for 8 h or at 600 C for 2 h. However, the Raman spectra of the same powders indicated the formation of tetragonal (rather than cubic) BaTiO{sub 3}, with traces of high-temperature hexagonal BaTiO{sub 3} and an intermediate phase, Ba{sub 2}Ti{sub 2}O{sub 5}{center_dot}CO{sub 3}. A solid-state reaction between BaCO{sub 3} and TiO{sub 2} was concluded as not being responsible for the BaTiO{sub 3} formation; rather, BaTiO{sub 3} formed directly by thermal decomposition of the intermediate Ba{sub 2}Ti{sub 2}O{sub 5}{center_dot}CO{sub 3} phase at temperatures >500 C. In addition, by Raman scattering measurements, the intermediate Ba{sub 2}Ti{sub 2}O{sub 5}{center_dot}CO{sub 3} phase was found to be unstable in ambient air, yielding BaCO{sub 3} as one of the decomposed products.

Arima, Momoko; Kakihana, Masato; Nakamura, Yoshiyuki; Yashima, Masatomo; Yoshimura, Masahiro [Tokyo Inst. of Tech., Yokohama (Japan)

1996-11-01

484

Fourth generation aluminum optics performance  

NASA Astrophysics Data System (ADS)

While post-polish has previously been shown to greatly enhance the surface quality, surface roughness, and surface figure of single-point diamond turned Aluminum mirrors, the field of bare Aluminum polishing continues to advance. New results demonstrating improvement in mid-spatial frequency errors and methods for adapting to a wider range of Aluminum materials constitute the next generation of polished Aluminum mirrors. These results show new levels of surface finish, correlated with BRDF measurements. Complimentary enhancements have been made by achieving new levels of precision in the placement of the optical axis relative to datum features, enabling significant alignment time savings.

Carrigan, Keith; Patel, Ankit

2013-09-01

485

Laser welding of aluminum alloys  

SciTech Connect

Recent interest in reducing the weight of automobiles to increase fuel mileage has focused attention on the use of aluminum and associated joining technologies. Laser beam welding is one of the more promising methods for high speed welding of aluminum. Consequently, substantial effort has been expended in attempting to develop a robust laser beam welding process. Early results have not been very consistent in the process requirements but more definitive data has been produced recently. This paper reviews the process parameters needed to obtain consistent laser welds on 5,000 series aluminum alloys and discusses the research necessary to make laser processing of aluminum a reality for automotive applications.

Leong, K.H.; Sabo, K.R.; Sanders, P.G. [Argonne National Lab., IL (United States). Technology Development Div.; Spawr, W.J.

1997-03-01

486

Mineral of the month: aluminum  

USGS Publications Warehouse

Aluminum is the second most abundant metallic element in Earth’s crust after silicon. Even so, it is a comparatively new industrial metal that has been produced in commercial quantities for little more than 100 years. Aluminum is lightweight, ductile, malleable and corrosion resistant, and is a good conductor of heat and electricity. Weighing about one-third as much as steel or copper per unit of volume, aluminum is used more than any other metal except iron. Aluminum can be fabricated into desired forms and shapes by every major metalworking technique to add to its versatility.

Plunkert, Patricia A.

2005-01-01

487

Aluminum-lithium for aerospace  

SciTech Connect

Aluminum-lithium alloys were developed primarily to reduce the weight of aircraft and aerospace structures. Lithium is the lightest metallic element, and each 1% of lithium added to aluminum reduces alloy density by about 3% and increases modulus by about 5%. Though lithium has a solubility limit of 4.2% in aluminum, the amount of lithium ranges between 1 and 3% in commercial alloys. Aluminum-lithium alloys are most often selected for aerospace components because of their low density, high strength, and high specific modulus. However, other applications now exploit their excellent fatigue resistance and cryogenic toughness.

Fielding, P.S.; Wolf, G.J. [Reynolds Metals Co., Richmond, VA (United States)

1996-10-01

488

Elastic scattering of electrons by gadolinium and barium atoms  

NASA Astrophysics Data System (ADS)

Total and differential cross-sections for elastic scattering of electrons from gadolinium and barium atoms in a wide energy range were calculated. In the low- and intermediate-energy regions, the phase theory of elastic scattering was used. At low incident energies (<10 eV), an additional polarization potential was introduced. At high incident energies, the Born approximation (keV range) and the Rutherford formula (MeV range) were applied. Our results are in rather good agreement with experimental data of Romanyuk et al. (Pis'ma Zh. Eksp. Teor. Fiz. 32 (1980) 472) for elastic scattering of very-low-energy electrons from barium atoms which confirm its reliability. This agreement is important because these experimental results are in serious disagreement with theoretical calculations of Szmytkowski and Sienkiewicz (Phys. Rev. A 50 (1994) 4007).

Miloshevsky, G. V.; Tolkach, V. I.; Rozin, S.; Shani, G.

2000-08-01

489

Electromagnetic properties of photodefinable barium ferrite polymer composites  

NASA Astrophysics Data System (ADS)

This article reports the magnetic and microwave properties of a Barium ferrite powder suspended in a polymer matrix. The sizes for Barium hexaferrite powder are 3-6 ?m for coarse and 0.8-1.0 ?m for the fine powder. Ratios 1:1 and 3:1 (by mass) of ferrite to SU8 samples were characterized and analyzed for predicting the necessary combinations of these powders with SU8 2000 Negative photoresist. The magnetization properties of these materials were equally determined and were analyzed using Vibrating Sample Magnetometer (VSM). The Thru, Reflect, Line (TRL) calibration technique was employed in determining complex relative permittivity and permeability of the powders and composites with SU8 between 26.5 and 40 GHz.

Sholiyi, Olusegun; Lee, Jaejin; Williams, John D.

2014-07-01

490

Observations and theory of the AMPTE magnetotail barium releases  

NASA Technical Reports Server (NTRS)

The barium releases in the magnetotail during the Active Magnetospheric Particle Tracer Explorers (AMPTE) operation were monitored by ground-based imagers and by instruments on the Ion Release Module. After each release, the data show the formation of a structured diamagnetic cavity. The cavity grows until the dynamic pressure of the expanding ions balances the magnetic pressure on its surface. The magnetic field inside the cavity is zero. The barium ions collect on the surface of the cavity, producing a shell. Plasma irregularities form along magnetic field lines draped over the surface of the cavity. The scale size of the irregularities is nearly equal to the thickness of the shell. The evolution and structuring of the diamagnetic cavity are modeled using magnetohydrodynamics theory.

Bernhardt, P. A.; Roussel-Dupre, R. A.; Pongratz, M. B.; Haerendel, G.; Valenzuela, A.

1987-01-01

491

Numerical simulation of a radially injected barium cloud  

NASA Technical Reports Server (NTRS)

Electrostatic two-dimensional numerical simulations of a radially symmetric barium injection experiment demonstrate that ions created by solar UV irradiation are electrostatically bound to the electrons which remain tied to the field lines on which they are created. Two possible instabilities are identified, but neither of them causes the barium plasma cloud to polarize in a way that would permit the plasma to keep up with the neutrals. In a second model, the velocity of the neutrals is allowed to be a function of the azimuthal angle. Here, a portion of the cloud does polarize in a way that allows a portion of the plasma to detach and move outward at the approximate speed of the neutrals. No rapid detachment is found when only the density of the neutrals is given an azimuthal asymmetry.

Swift, D. W.; Wescott, E. M.

1981-01-01

492

NASA/Max Planck Institute Barium Ion Cloud Project.  

NASA Technical Reports Server (NTRS)

NASA and the Max Planck Institute for Extraterrestrial Physics (MPE), Munich, Germany, conducted a cooperative experiment involving the release and study of a barium cloud at 31,500 km altitude near the equatorial plane. The release was made near local magnetic midnight on Sept. 21, 1971. The MPE-built spacecraft contained a canister of 16 kg of Ba CuO mixture, a two-axis magnetometer, and other payload instrumentation. The objectives of the experiment were to investigate the interaction of the ionized barium cloud with the ambient medium and to deduce the properties of electric fields in the proximity of the release. An overview of the project is given to briefly summarize the organization, responsibilities, objectives, instrumentation, and operational aspects of the project.

Brence, W. A.; Carr, R. E.; Gerlach, J. C.; Neuss, H.

1973-01-01

493

Study of the photovoltaic effect in thin film barium titanate  

NASA Technical Reports Server (NTRS)

Ferroelectric films of barium titanate were synthesized on silicon and quartz substrates, and the photoelectric effect in the structure consisting of metal deposited ferroelectric barium titanate film silicon was studied. A photovoltage with polarity that depends on the direction of the remanent polarization was observed. The deposition of BaTiO3 on silicon and fused quartz substrates was accomplished by an rf sputtering technique. A series of experiments to study the growth of ferroelectric BaTiO3 films on single crystal silicon and fused quartz substrates were conducted. The ferroelectric character in these films was found on the basis of evidence from the polarization electric field hysteresis loops, capacitance voltage and capacitance temperature techniques and from X-ray diffraction studies.

Grannemann, W. W.; Dharmadhikari, V. S.

1982-01-01

494

Anomalies of piezoelectric coefficients in barium titanate thin films  

NASA Astrophysics Data System (ADS)

Modeling of electromechanical devices involves the use of different material coefficients, whose measurement is a difficult task, especially when the problem concerns thin films. Required coefficients of thin films could be found theoretically, using known values of the bulk constants. Electromechanical coefficients of barium titanate thin films are still unknown; therefore, it is expedient to carry out their calculations. We give here the full set of electromechanical coefficients of barium titanate thin films for the whole range of technologically available misfit strains. In the present paper, piezoelectric coefficients as functions of a misfit strain were calculated. It was revealed that piezoelectric coefficients exhibit anomalies at phase boundaries and inside the monoclinic r-phase as well. The obtained results allow finding the required values of the thin-film parameters, varying the misfit strain.

Shirokov, Vladimir; Kalinchuk, Valery; Shakhovoy, Roman; Yuzyuk, Yury

2014-11-01

495

Spectroscopy of barium attached to superfluid helium clusters  

NASA Astrophysics Data System (ADS)

To complement the data on absorption spectra of alkaline earth atoms attached to superfluid helium clusters we are reporting on barium atoms attached to 4HeN. The absorption spectrum of the lowest singlet transition is blue-shifted and strongly broadened compared to the corresponding unperturbed Ba (6s6p1Po1?6s21S0) transition in accord with the observations on Sr and Ca added to HeN [F. Stienkemeier, F. Meier, and H.O. Lutz: J. Chem. Phys. 107(24), 10816 (1997)]. Moreover, we compare the asymptotic values of shift and width of the excitation spectrum with increasing helium cluster size He ( 1000 up to 10000) to those found for barium atoms in bulk liquid helium.

Stienkemeier, F.; Meier, F.; Lutz, H. O.

496

Nanoscale inhomogeneities in yttrium-barium-copper-oxide (YBCO) superconductors  

Microsoft Academic Search

X-ray diffraction studies at the Advanced Photon Source reveal that nanoscale inhomogeneities, electronic or structural in origin, form in yttrium-barium-copper-oxide (YBa_2Cu_3O_6+x) superconductors and coexist with the superconducting (SC) state. Diffuse scattering from these inhomogeneous superstructures is due to atomic displacements with respect to equilibrium lattice sites (Z. Islam et al. Phys. Rev. B 66, 92501 (2002)), that are characterized by

Zahirul Islam; S. K. Sinha; J. C. Lang; X. Liu; D. Haskel; S. C. Moss; G. Srajer; B. W. Veal; D. Wermeille; D. R. Lee; D. R. Haeffner; U. Welp; P. Wochner

2004-01-01

497

Isotopic Masses of Hydrogen, Chlorine, Barium, Cerium, and Neodymium  

Microsoft Academic Search

The 16-in. double-focusing mass spectrometer at the University of Minnesota has been employed to measure the atomic mass of H1 and the atomic masses and isotopic mass differences of chlorine, barium, cerium, and neodymium. Recent improvements in instrumentation have increased the precision of both narrow and wide doublet measurements. The doublet C11H22-C12H10 was used to relate the H1 mass directly

Jay L. Benson; Walter H. Johnson

1966-01-01

498

Synthesis and Electromagnetic Properties of Polyaniline-barium Ferrite Nanocomposite  

Microsoft Academic Search

The polyaniline (PANI)-barium ferrite composite with magnetic behavior was synthesized by in situ polymerization of aniline in the presence of BaFe12O19 nanoparticles of 60–80 nm in diameters. The structure, morphology and magnetic properties of samples were characterized by powder X-ray diffraction, Fourier transform infrared, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometer technique. The results of spectroanalysis indicated

Yuan-Xun Li; Huai-Wu Zhang; Ying-Li Liu; John Q. Xiao

2007-01-01

499

In-situ laser deposition of barium ferrite films  

Microsoft Academic Search

Barium ferrite films with high coercivity, large magnetic anisotropy, good crystal orientation and crystallinity with hexagonal symmetry have been prepared on single crystal sapphire substrates by laser in-situ deposition. The structures of these films were characterized by X-ray diffractometry. X-ray diffraction pattern shows a preferential c-axis orientation normal to the film plane at a deposition temperature of 900°C. The magnetic

W. D. Song; Y. F. Lu; W. J. Wang; C. K. Ong; J. P. Wang; T. C. Chong

1999-01-01

500

Microstructure of composite material with powders of barium ferrite  

Microsoft Academic Search

Purpose: The aim of the present work is the microstructure characterization of commercial powder BaFe12O19 (as-prepared) and composite material with BaFe12O19 powders and polymer matrix, using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscopy) methods. Design\\/methodology\\/approach: The morphology of barium ferrite powders and a fracture surface of the examined composite material was realized by using the scanning electron microscope. The

R. Nowosielski; R. Babilas; G. Dercz; L. Paj?k b