Characterization of the distribution of the sintering activator boron in powder metallurgical steels with SIMS.

PubMed

Krecar, Dragan; Vassileva, Vassilka; Danninger, Herbert; Hutter, Herbert

2004-06-01

Powder metallurgy is a well-established method for manufacturing ferrous precision parts. A very important step is sintering, which can be strongly enhanced by the formation of a liquid phase during the sintering process. Boron activates this process by forming such a liquid phase at about 1200 degrees C. In this work, the sintering of Fe-B was performed under the protective atmospheres of hydrogen, argon or nitrogen. Using different grain sizes of the added ferroboron leads to different formations of pores and to the formation of secondary pores. The effect of boron was investigated by means of Secondary Ion Mass Spectrometry (SIMS) supported by Scanning Electron Microscopy (SEM) and Light Microscopy (LM). To verify the influence of the process parameters on the mechanical properties, the microstructure (pore shape) was examined and impact energy measurements were performed. The concentrations of B in different samples were varied from 0.03-0.6 weight percent (wt%). Higher boron concentrations are detectable by EPMA, whereas the distributions of boron in the samples with interesting overall concentration in the low wt% range are only detectable by means of SIMS. This work shows that the distribution of boron strongly depends on its concentration and the sintering atmosphere used. At low concentration (up to 0.1 wt%) there are boride precipitations; at higher concentration there is a eutectic iron-boron grain boundary network. There is a decrease of the impact energy observed that correlates with the amount of eutectic phase.

Evaluation of boron-epoxy-reinforced titanium tubular truss for application to a space shuttle booster thrust structure

NASA Technical Reports Server (NTRS)

Corvelli, N.; Carri, R.

1972-01-01

Results of a study to demonstrate the applicability of boron-epoxy-composite-reinforced titanium tubular members to a space shuttle booster thrust structure are presented and discussed. The experimental results include local buckling of all-composite and composite-reinforced-metal cylinders with low values of diameter-thickness ratio, static tests on composite-to-metal bonded step joints, and a test to failure of a boron-epoxy-reinforced titanium demonstration truss. The demonstration truss failed at 118 percent of design ultimate load. Test results and analysis for all specimens and the truss are compared. Comparing an all-titanium design and a boron-epoxy-reinforced-titanium (75 percent B-E and 25 percent Ti) design for application to the space shuttle booster thrust structure indicates that the latter would weigh approximately 24 percent less. Experimental data on the local buckling strength of cylinders with a diameter-thickness ratio of approximately 50 are needed to insure that undue conservatism is not used in future designs.

Radiological analysis of plutonium glass batches with natural/enriched boron

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

Rainisch, R.

2000-06-22

The disposition of surplus plutonium inventories by the US Department of Energy (DOE) includes the immobilization of certain plutonium materials in a borosilicate glass matrix, also referred to as vitrification. This paper addresses source terms of plutonium masses immobilized in a borosilicate glass matrix where the glass components include both natural boron and enriched boron. The calculated source terms pertain to neutron and gamma source strength (particles per second), and source spectrum changes. The calculated source terms corresponding to natural boron and enriched boron are compared to determine the benefits (decrease in radiation source terms) for to the use ofmore » enriched boron. The analysis of plutonium glass source terms shows that a large component of the neutron source terms is due to (a, n) reactions. The Americium-241 and plutonium present in the glass emit alpha particles (a). These alpha particles interact with low-Z nuclides like B-11, B-10, and O-17 in the glass to produce neutrons. The low-Z nuclides are referred to as target particles. The reference glass contains 9.4 wt percent B{sub 2}O{sub 3}. Boron-11 was found to strongly support the (a, n) reactions in the glass matrix. B-11 has a natural abundance of over 80 percent. The (a, n) reaction rates for B-10 are lower than for B-11 and the analysis shows that the plutonium glass neutron source terms can be reduced by artificially enriching natural boron with B-10. The natural abundance of B-10 is 19.9 percent. Boron enriched to 96-wt percent B-10 or above can be obtained commercially. Since lower source terms imply lower dose rates to radiation workers handling the plutonium glass materials, it is important to know the achievable decrease in source terms as a result of boron enrichment. Plutonium materials are normally handled in glove boxes with shielded glass windows and the work entails both extremity and whole-body exposures. Lowering the source terms of the plutonium batches will make the handling of these materials less difficult and will reduce radiation exposure to operating workers.« less

Fiber composite fan blade impact improvement

NASA Technical Reports Server (NTRS)

Graff, J.; Stoltze, L.; Varholak, E. M.

1976-01-01

The improved foreign object damage resistance of a metal matrix advanced composite fan blade was demonstrated. The fabrication, whirl impact test and subsequent evaluation of nine advanced composite fan blades of the "QCSEE" type design were performed. The blades were designed to operate at a tip speed of 282 m/sec. The blade design was the spar/shell type, consisting of a titanium spar and boron/aluminum composite airfoils. The blade retention was designed to rock on impact with large birds, thereby reducing the blade bending stresses. The program demonstrated the ability of the blades to sustain impacts with up to 681 g slices of birds at 0.38 rad with little damage (only 1.4 percent max weight loss) and 788 g slices of birds at 0.56 rad with only 3.2 percent max weight loss. Unbonding did not exceed 1.1 percent of the post-test blade area during any of the tests. All blades in the post-test condition were judged capable of operation in accordance with the FAA guidelines for medium and large bird impacts.

Use of Atomic Fuels for Rocket-Powered Launch Vehicles Analyzed

NASA Technical Reports Server (NTRS)

Palaszewski, Bryan A.

1999-01-01

At the NASA Lewis Research Center, the launch vehicle gross lift-off weight (GLOW) was analyzed for solid particle feed systems that use high-energy density atomic propellants (ref. 1). The analyses covered several propellant combinations, including atoms of aluminum, boron, carbon, and hydrogen stored in a solid cryogenic particle, with a cryogenic liquid as the carrier fluid. Several different weight percents for the liquid carrier were investigated, and the GLOW values of vehicles using the solid particle feed systems were compared with that of a conventional oxygen/hydrogen (O2/H2) propellant vehicle. Atomic propellants, such as boron, carbon, and hydrogen, have an enormous potential for high specific impulse Isp operation, and their pursuit has been a topic of great interest for decades. Recent and continuing advances in the understanding of matter, the development of new technologies for simulating matter at its most basic level, and manipulations of matter through microtechnology and nanotechnology will no doubt create a bright future for atomic propellants and an exciting one for the researchers exploring this technology.

Computational Design of Epoxy/ Boron Carbide Nanocomposites for Radiation Shielding Applications

NASA Astrophysics Data System (ADS)

Bejagam, Karteek; Galehdari, Nasim; Espinosa, Ingrid; Deshmukh, Sanket A.; Kelkar, Ajit D.

An individual working in industries that include nuclear power plants, healthcare industry, and aerospace are knowingly or unknowingly exposed to radiations of different energies. Exposure to high-energy radiations such as α/ β particle emissions or gamma ray electromagnetic radiations enhances the health risks that can lead to carcinogenesis, cardiac problems, cataracts, and other acute radiation syndromes. The best possible solution to protect one from the exposure to radiations is shielding. In the present study, we have developed a new algorithm to generate a range of different structures of Diglycidyl Ether of Bisphenol F (EPON 862) and curing agent Diethylene Toluene Diamine (DETDA) resins with varying degrees of crosslinking. 3, 5, and 10 weight percent boron carbide was employed as filling materials to study its influence on the thermal and mechanical properties of composite. We further conduct the reactive molecular dynamics (RMD) simulations to investigate the effect of radiation exposure on the structural, physical, and mechanical properties of these Epoxy/Boron Carbide nanocomposites. Where possible the simulation results were compared with the experimental data.

The elevated temperature mechanical properties of silicon nitride/boron nitride fibrous monoliths

NASA Astrophysics Data System (ADS)

Trice, Rodney Wayne

A unique, all-ceramic material capable of non-brittle fracture via crack deflection has been characterized from 25sp°C through 1400sp°C. This material, called fibrous monoliths (FMs), was comprised of unidirectionally aligned 250 mum diameter cells of silicon nitride surrounded by 10 mum thick cell boundaries of boron nitride. Six weight percent yttria and two weight percent alumina were added to the silicon nitride to aid in densification. TEM experiments revealed that the sintering aids used to densify the silicon nitride cells were migrating into the boron nitride cell boundary during hot-pressing and that a fine network of micro-cracks existed between basal planes of boron nitride. Elevated temperature four point bending tests were performed on fibrous monolith ceramics from room temperature through 1400sp°C. Peak strengths of FMs averaged 510 MPa for specimens tested at room temperature through 176 MPa at 1400sp°C. Work of fractures ranged from 7300 J/msp2 to 3200 J/msp2 under the same temperature conditions. The interfacial fracture energy of boron nitride, GammasbBN, as a function of temperature has been determined using the Charalambides method. The fracture energy of boron nitride is approximately 40 J/msp2 and remained constant from 25sp°C through 950sp°C. A sharp increase in GammasbBN, to about 60 J/msp2, was observed at 1000sp°C-1050sp°C. This increase in GammasbBN was attributed to interactions of the crack tip with the cell boundary glassy phase. Subsequent measurements at 1075sp°C indicated a marked decrease in GammasbBN to near 40 J/msp2 before plateauing at 17-20 J/msp2 in the 1200sp°C-1300sp°C regime. The Mode I fracture toughness of silicon nitride was also determined using the single edge precracked beam method as a function of temperature. The He and Hutchinson model relating crack deflection at an interface to the Dundurs' parameter was applied to the current data set using the temperature dependent fracture energies of the boron nitride and the silicon nitride. A more refractory fibrous monolith was fabricated in an effort to extend the high temperature properties of SN/BN fibrous monoliths. Only 4 wt.% yttria was added to the silicon nitride to aid in densification. The presence of residual carbon following binder burnout was proposed to be responsible for the formation of melilite, a phase known to undergo severe oxidation between 900sp°C-1100sp°C. When residual carbon was removed prior to hot-pressing with a post-binder burnout heat treatment at 400sp°C in air this phase was not present. A room temperature strength of 553 MPa and a work of fracture of 6700 J/msp2 was observed. A strength of 293 MPa was measured at 1400sp°C.

METHOD OF PREPARING RADIOACTIVE CESIUM SOURCES

DOEpatents

Quinby, T.C.

1963-12-17

A method of preparing a cesium-containing radiation source with physical and chemical properties suitable for high-level use is presented. Finely divided silica is suspended in a solution containing cesium, normally the fission-product isotope cesium 137. Sodium tetraphenyl boron is then added to quantitatively precipitate the cesium. The cesium-containing precipitate is converted to borosilicate glass by heating to the melting point and cooling. Up to 60 weight percent cesium, with a resulting source activity of up to 21 curies per gram, is incorporated in the glass. (AEC)

Boron Diffusion in Surface-Treated Framing Lumber

Treesearch

Patricia K. Lebow; Stan T. Lebow; Steven A. Halverson

2013-01-01

The extent of boron penetration in framing lumber treated by spray applications during construction is not well quantified. This study evaluated the effect of formulation and concentration on diffusion of boron in lumber specimens that were equilibrated in conditions that produced wood moisture contents of 18 to 21 percent. One set of specimens was pressure treated...

Fillers for improved graphite fiber retention by polymer matrix composites

NASA Technical Reports Server (NTRS)

House, E. E.; Sheppard, C. H.

1981-01-01

The results of a program designed to determine the extent to which elemental boron and boron containing fillers added to the matrix resin of graphite/epoxy composites prevent the release of graphite fibers when the composites are exposed to fire and impact conditions are described. The fillers evaluated were boron, boron carbide and aluminum boride. The conditions evaluated were laboratory simulations of those that could exist in the event of an aircraft crash and burn situation. The baseline (i.e., unfilled) laminates evaluated were prepared from commercially available graphite/epoxy. The baseline and filled laminates' mechanical properties, before and after isothermal and humidity aging, also were compared. It was found that a small amount of graphite fiber was released from the baseline graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that the addition of boron and boron containing fillers to the resin matrix eliminated this fiber release. Mechanical properties of laminates containing the boron and boron containing fillers were lower than those of the baseline laminates. These property degradations for two systems: boron (5 micron) at 2.5 percent filler loading, and boron (5 micron) at 5.0 percent filler loading do not appear severe enough to preclude their use in structural composite applications.

Design and fabrication of a boron reinforced intertank skirt

NASA Technical Reports Server (NTRS)

Henshaw, J.; Roy, P. A.; Pylypetz, P.

1974-01-01

Analytical and experimental studies were performed to evaluate the structural efficiency of a boron reinforced shell, where the medium of reinforcement consists of hollow aluminum extrusions infiltrated with boron epoxy. Studies were completed for the design of a one-half scale minimum weight shell using boron reinforced stringers and boron reinforced rings. Parametric and iterative studies were completed for the design of minimum weight stringers, rings, shells without rings and shells with rings. Computer studies were completed for the final evaluation of a minimum weight shell using highly buckled minimum gage skin. The detail design is described of a practical minimum weight test shell which demonstrates a weight savings of 30% as compared to an all aluminum longitudinal stiffened shell. Sub-element tests were conducted on representative segments of the compression surface at maximum stress and also on segments of the load transfer joint. A 10 foot long, 77 inch diameter shell was fabricated from the design and delivered for further testing.

Enhanced-wetting, boron-based liquid-metal ion source and method

DOEpatents

Bozack, Michael J.; Swanson, Lynwood W.; Bell, Anthony E.; Clark Jr., William M.; Utlaut, Mark W.; Storms, Edmund K.

1999-01-01

A binary, boron-based alloy as a source for field-emission-type, ion-beam generating devices, wherein boron predominates in the alloy, preferably with a presence of about 60 atomic percent. The other constituent in the alloy is selected from the group of elements consisting of nickel, palladium and platinum. Predominance of boron in these alloys, during operation, promotes combining of boron with trace impurities of carbon in the alloys to form B.sub.4 C and thus to promote wetting of an associated carbon support substrate.

Enhanced-wetting, boron-based liquid-metal ion source and method

DOEpatents

Bozack, M.J.; Swanson, L.W.; Bell, A.E.; Clark, W.M. Jr.; Utlaut, M.W.; Storms, E.K.

1999-02-16

A binary, boron-based alloy as a source for field-emission-type, ion-beam generating devices, wherein boron predominates in the alloy, preferably with a presence of about 60 atomic percent is disclosed. The other constituent in the alloy is selected from the group of elements consisting of nickel, palladium and platinum. Predominance of boron in these alloys, during operation, promotes combining of boron with trace impurities of carbon in the alloys to form B{sub 4}C and thus to promote wetting of an associated carbon support substrate. 1 fig.

Energy release properties of amorphous boron and boron-based propellant primary combustion products

NASA Astrophysics Data System (ADS)

Liang, Daolun; Liu, Jianzhong; Xiao, Jinwu; Xi, Jianfei; Wang, Yang; Zhang, Yanwei; Zhou, Junhu

2015-07-01

The microstructure of amorphous boron and the primary combustion products of boron-based fuel-rich propellant (hereafter referred to as primary combustion products) was analyzed by scanning electron microscope. Composition analysis of the primary combustion products was carried out by X-ray diffraction and X-ray photoelectron spectroscopy. The energy release properties of amorphous boron and the primary combustion products were comparatively studied by laser ignition experimental system and thermogravimetry-differential scanning calorimetry. The primary combustion products contain B, C, Mg, Al, B4C, B13C2, BN, B2O3, NH4Cl, H2O, and so on. The energy release properties of primary combustion products are different from amorphous boron, significantly. The full-time spectral intensity of primary combustion products at a wavelength of 580 nm is ~2% lower than that of amorphous boron. The maximum spectral intensity of the former at full wave is ~5% higher than that of the latter. The ignition delay time of primary combustion products is ~150 ms shorter than that of amorphous boron, and the self-sustaining combustion time of the former is ~200 ms longer than that of the latter. The thermal oxidation process of amorphous boron involves water evaporation (weight loss) and boron oxidation (weight gain). The thermal oxidation process of primary combustion products involves two additional steps: NH4Cl decomposition (weight loss) and carbon oxidation (weight loss). CL-20 shows better combustion-supporting effect than KClO4 in both the laser ignition experiments and the thermal oxidation experiments.

Effects of boron on structure and antioxidative activities of spleen in rats.

PubMed

Hu, Qianqian; Li, Shenghe; Qiao, Enmei; Tang, Zhongtao; Jin, Erhui; Jin, Guangming; Gu, Youfang

2014-04-01

In order to determine the relationship between boron and development of the spleen, especially in the promoting biological effects, we examined the effects of different levels of boron on weight, organ index, microstructure, and antioxidative activities of the spleen in rats. Sprague-Dawley (SD) rats were selected and treated with different concentrations of boron, and then, the organs were resected and weighed. One half of the tissue was fixed and embedded in paraffin to observe tissue structure changes. The other half of the tissue was homogenated for determining the antioxidant activities. The results showed that 40 mg/L of boron could increase weight, organ indexes, and antioxidant capacity of spleens and improve the spleen tissue structure, while the boron concentration above 80 mg/L could decrease weight, organ indexes, and antioxidant capacity of spleens and damage the spleen tissue structure. The higher the concentration, the more serious the damage was. Especially at the concentration of 640 mg/L, it could significantly inhibit the development of the spleen and even exhibit toxic effect. Hence, low boron concentration played a protective role in the development of the spleen, while high boron concentration could damage the organs and even produce toxic effect.

In vivo percutaneous absorption of boron as boric acid, borax, and disodium octaborate tetrahydrate in humans: a summary.

PubMed

Wester, R C; Hui, X; Maibach, H I; Bell, K; Schell, M J; Northington, D J; Strong, P; Culver, B D

1998-01-01

Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry, which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological matrices. This made it possible, in the presence of comparatively large natural dietary boron intakes for the in vivo segment of this study, to quantify the boron passing through skin. Human volunteers were dosed with 10B-enriched boric acid, 5.0%, borax, 5.0%, or disodium octaborate tetrahydrate, 10% in aqueous solutions. Urinalysis, for boron and changes in boron isotope ratios, was used to measure absorption. Boric acid in vivo percutaneous absorption was 0.226 (SD = 0.125) mean percent dose, with flux and permeability constant (Kp) calculated at 0.009 microg/cm2/h and 1.9 x 10(-7) cm/h, respectively. Borax absorption was 0.210 (SD = 0.194) mean percent dose, with flux and Kp calculated at 0.009 microg/cm2/h and 1.8 x 10(-7) cm/h, respectively. DOT absorption was 0.122 (SD = 0.108) mean percent, with flux and Kp calculated at 0.01 microg/cm2/h and 1.0 x 10(-7) cm/h, respectively. Pretreatment with the potential skin irritant 2% sodium lauryl sulfate had no effect on boron skin absorption. These in vivo results show that percutaneous absorption of boron, as boric acid, borax, and disodium octaborate tetrahydrate, through intact human skin is low and is significantly less than the average daily dietary intake. This very low boron skin absorption makes it apparent that, for the borates tested, the use of gloves to prevent systemic uptake is unnecessary. These findings do not apply to abraded or otherwise damaged skin.

Boron enhances strength and alters mineral composition of bone in rabbits fed a high energy diet.

PubMed

Hakki, Sema S; Dundar, Niyazi; Kayis, Seyit Ali; Hakki, Erdogan E; Hamurcu, Mehmet; Kerimoglu, Ulku; Baspinar, Nuri; Basoglu, Abdullah; Nielsen, Forrest H

2013-04-01

An experiment was performed to determine whether boron had a beneficial effect on bone strength and composition in rabbits with apparent adiposity induced by a high energy diet. Sixty female New Zealand rabbits, aged 8 months, were randomly divided into five groups with the following treatments for seven months: control 1, fed alfalfa hay only (5.91 MJ/kg); control 2, high energy diet (11.76 MJ and 3.88 mg boron/kg); B10, high energy diet+10 mg/kg body weight boron gavage/96 h; B30, high energy diet+30 mg/kg body weight boron gavage/96 h; B50, high energy diet+50mg/kg body weight boron gavage/96 h. Bone boron concentrations were lowest in rabbits fed the high energy diet without boron supplementation, which suggested an inferior boron status. Femur maximum breaking force was highest in the B50 rabbits. Tibia compression strength was highest in B30 and B50 rabbits. All boron treatments significantly increased calcium and magnesium concentrations, and the B30 and B50 treatments increased the phosphorus concentration in tibia of rabbits fed the high energy diet. The B30 treatment significantly increased calcium, phosphorus and magnesium concentrations in femur of rabbits fed the high energy diet. Principal component analysis of the tibia minerals showed that the three boron treatments formed a separate cluster from controls. Discriminant analysis suggested that the concentrations of the minerals in femur could predict boron treatment. The findings indicate boron has beneficial effects on bone strength and mineral composition in rabbits fed a high energy diet. Copyright © 2012 Elsevier GmbH. All rights reserved.

Elevated temperature properties of boron/aluminum composites

NASA Technical Reports Server (NTRS)

Sullivan, P. G.

1978-01-01

The high temperature properties of boron/aluminum composites, fabricated by an air diffusion bonding technique utilizing vacuum-bonded monolayer tape are reported. Seventeen different combinations of matrix alloy, reinforcement diameter, reinforcement volume percent, angle-ply and matrix enhancement (i.e. titanium cladding and interleaves) were fabricated, inspected, and tested. It is shown that good to excellent mechanical properties could be obtained for air-bonded boron/aluminum composites and that these properties did not decrease significantly up to a test temperature of at least 260 C. Composites made with 8 mil B/W fiber show a much greater longitudinal strength dependence on volume percent fiber than composites made with 5.6 mil fiber. The addition of titanium caused difficulties in composite bonding and yielded composites with reduced strength.

Evaluation of a metal shear web selectively reinforced with filamentary composites for space shuttle application. Phase 3 Summary report: Shear web component testing and analysis

NASA Technical Reports Server (NTRS)

Laakso, J. H.; Straayer, J. W.

1973-01-01

Three large scale advanced composite shear web components were tested and analyzed to evaluate application of the design concept to a space shuttle orbiter thrust structure. The shear web design concept consisted of a titanium-clad + or - 45 deg boron/epoxy web laminate stiffened with vertical boron/epoxy reinforced aluminum stiffeners. The design concept was evaluated to be efficient and practical for the application that was studied. Because of the effects of buckling deflections, a requirement is identified for shear buckling resistant design to maximize the efficiency of highly-loaded advanced composite shear webs. An approximate analysis of prebuckling deflections is presented and computer-aided design results, which consider prebuckling deformations, indicate that the design concept offers a theoretical weight saving of 31 percent relative to all metal construction. Recommendations are made for design concept options and analytical methods that are appropriate for production hardware.

Thermal neutron shield and method of manufacture

DOEpatents

Metzger, Bert Clayton; Brindza, Paul Daniel

2014-03-04

A thermal neutron shield comprising boron shielding panels with a high percentage of the element Boron. The panel is least 46% Boron by weight which maximizes the effectiveness of the shielding against thermal neutrons. The accompanying method discloses the manufacture of boron shielding panels which includes enriching the pre-cursor mixture with varying grit sizes of Boron Carbide.

Dietary boron: possible roles in human and animal physiology

USDA-ARS?s Scientific Manuscript database

Boron is a bioactive element of low molecular weight. Since discovery of the first boron biomolecule, boromycin, in 1967, several other similar biomolecules are now well-characterized. Most recently described was a bacterial cell-to-cell communication signal that requires boron, autoinducer-II. Boro...

Boron/aluminum skins for the DC-10 aft pylon

NASA Technical Reports Server (NTRS)

Elliott, S. Y.

1975-01-01

Boron/aluminum pylon boat tail skins were designed and fabricated and installed on the DC-10 aircraft for a 5-year flight service demonstration test. Inspection and tests of the exposed skins will establish the ability of the boron/aluminum composite to withstand long time flight service conditions, which include exposure to high temperatures, sonic fatigue, and flutter. The results of a preliminary testing program yield room temperature and elevated temperature data on the tension, compression, in-plane shear, interlaminar shear, bolt bearing, and tension fatigue properties of the boron/aluminum laminates. Present technology was used in the fabrication of the skins. Although maximum weight saving was not sought, weight of the constant thickness boron/aluminum skin is 26% less than the chemically milled titanium skin.

Thermal neutron shield and method of manufacture

DOEpatents

Brindza, Paul Daniel; Metzger, Bert Clayton

2013-05-28

A thermal neutron shield comprising concrete with a high percentage of the element Boron. The concrete is least 54% Boron by weight which maximizes the effectiveness of the shielding against thermal neutrons. The accompanying method discloses the manufacture of Boron loaded concrete which includes enriching the concrete mixture with varying grit sizes of Boron Carbide.

Manufacturing Methods for Process Effects on Aluminum Casting Allowables

DTIC Science & Technology

1985-03-01

silicon ingot (25% Si) 4 . Copper as copper shot 5. Manganese as aluminum manganese ingot (10% Mn) 6 . Titanium and boron as titanium -boron wire 7. Silver...in stock form 4 . Silver in granule form. 5. Manganese (10 percent) in button form 6 . 201 refining salt ( Titanium -Boron) Melt chemistry is adjusted to...FAFB, OH 45433 4 . PERFORIN41N ORGANIZATION REPORT NUMBER(S) 5. MONITORING ORGANIZATION REPORT NUMSER(S) NOR 85-119 AFWAL-TR-.84- 4 117 I 6 *. NAME OF

Precision and Accuracy of Analysis for Boron in ITP Samples

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

Tovo, L.L.

'Inductively Coupled Plasma Emission Spectroscopy (ICPES) has been used by the Analytical Development Section (ADS) to measure boron in catalytic tetraphenylboron decomposition studies performed by the Waste Processing Technology (WPT) section. Analysis of these samples is complicated due to the presence of high concentrations of sodium and organic compounds. Previously, we found signal suppression in samples analyzed "as received". We suspected that the suppression was due to the high organic concentration (up to 0.01 molar organic decomposition products) in the samples. When the samples were acid digested prior to analysis, the suppression was eliminated. The precision of the reported boronmore » concentration was estimated as 10 percent based on the known precision of the inorganic boron standard used for calibration and quality control check of the ICPES analysis. However, a precision better than 10 percent was needed to evaluate ITP process operating parameters. Therefore, the purpose of this work was (1) to measure, instead of estimating, the precision of the boron measurement on ITP samples and (2) to determine the optimum precision attainable with current instrumentation.'« less

Resin char oxidation retardant for composites

NASA Technical Reports Server (NTRS)

Bowles, K. J.; Gluyas, R. E.

1981-01-01

Boron powder stabilizes char, so burned substances are shiny, smooth, and free of loose graphite fibers. Resin weight loss of laminates during burning in air is identical for the first three minutes for unfilled and boron-filled samples, then boron samples stabilize.

Neutron shielding behavior of thermoplastic natural rubber/boron carbide composites

NASA Astrophysics Data System (ADS)

Mat Zali, Nurazila; Yazid, Hafizal; Megat Ahmad, Megat Harun Al Rashid

2018-01-01

Many shielding materials have been designed against the harm of different types of radiation to the human body. Today, polymer-based lightweight composites have been chosen by the radiation protection industry. In the present study, thermoplastic natural rubber (TPNR) composites with different weight percent of boron carbide (B4C) fillers (0% to 30%) were fabricated as neutron shielding through melt blending method. Neutron attenuation properties of TPNR/B4C composites have been investigated. The macroscopic cross section (Σ), half value layer (HVL) and mean free path length (λ) of the composites have been calculated and the transmission curves have been plotted. The obtained results show that Σ, HVL and λ greatly depend on the B4C content. Addition of B4C fillers into TPNR matrix were found to enhance the macroscopic cross section values thus decrease the mean free path length (λ) and half value layer (HVL) of the composites. The transmission curves exhibited that the neutron transmission of the composites decreased with increasing shielding thickness. These results showed that TPNR/B4C composites have high potential for neutron shielding applications.

Analytical and experimental investigation of aircraft metal structures reinforced with filamentary composites. Phase 2: Structural fatigue, thermal cycling, creep, and residual strength

NASA Technical Reports Server (NTRS)

Blichfeldt, B.; Mccarty, J. E.

1972-01-01

Specimens representative of metal aircraft structural components reinforced with boron filamentary composites were manufactured and tested under cyclic loading, cyclic temperature, or continuously applied loading to evaluate some of the factors that affect structural integrity under cyclic conditions. Bonded, stepped joints were used throughout to provide composite-to-metal transition regions at load introduction points. Honeycomb panels with titanium or aluminum faces reinforced with unidirectional boron composite were fatigue tested at constant amplitude under completely reversed loading. Results indicated that the matrix material was the most fatigue-sensitive part of the design, with debonding initiating in the stepped joints. However, comparisons with equal weight all-metal specimens show a 10 to 50 times improved fatigue life. Fatigue crack propagation and residual strength were studied for several different stiffened panel concepts, and were found to vary considerably depending on the configuration. Composite-reinforced metal specimens were also subjected to creep and thermal cycling tests. Thermal cycling of stepped joint tensile specimens resulted in a ten percent decrease in residual strength after 4000 cycles.

Electric heater for nuclear fuel rod simulators

DOEpatents

McCulloch, Reginald W.; Morgan, Jr., Chester S.; Dial, Ralph E.

1982-01-01

The present invention is directed to an electric cartridge-type heater for use as a simulator for a nuclear fuel pin in reactor studies. The heater comprises an elongated cylindrical housing containing a longitudinally extending helically wound heating element with the heating element radially inwardly separated from the housing. Crushed cold-pressed preforms of boron nitride electrically insulate the heating element from the housing while providing good thermal conductivity. Crushed cold-pressed preforms of magnesia or a magnesia-15 percent boron nitride mixture are disposed in the cavity of the helical heating element. The coefficient of thermal expansion of the magnesia or the magnesia-boron nitride mixture is higher than that of the boron nitride disposed about the heating element for urging the boron nitride radially outwardly against the housing during elevated temperatures to assure adequate thermal contact between the housing and the boron nitride.

Lightweight Ceramic Insulation

NASA Technical Reports Server (NTRS)

Wheeler, W. H.; Creedon, J. F.

1986-01-01

Fiber burnout process yields low densities. Low density attained by process of sacrificial burnout. Graphite or carbon fibers mixed into slurry of silica, alumina, and boron-compound fibers in amounts ranging from 25 to 75 percent of total fiber content by weight. Mixture formed into blocks and dried. Blocks placed in kiln and heated to 1,600 degrees F(870 degrees C) for several hours. Graphite or carbon fibers slowly oxidize away, leaving voids and reducing block density. Finally, blocks heated to 2,350 degrees F (1,290 degrees C) for 90 minutes to bond remaining ceramic fibers together. Developed for use on Space Shuttle and other spacecraft, rigid insulation machined to requisite shape and bonded in place.

High weldability nickel-base superalloy

DOEpatents

Gibson, Robert C.; Korenko, Michael K.

1980-01-01

This is a nickel-base superalloy with excellent weldability and high strength. Its composition consists essentially of, by weight percent, 10-20 iron, 57-63 nickel, 7-18 chromium, 4-6 molybdenum, 1-2 niobium, 0.2-0.8 silicon, 0.01-0.05 zirconium, 1.0-2.5 titanium, 1.0-2.5 aluminum, 0.02-0.06 carbon, and 0.002-0.015 boron. The weldability and strength of this alloy give it a variety of applications. The long-time structural stability of this alloy together with its low swelling under nuclear radiation conditions, make it especially suitable for use as a duct material and controlling element cladding for sodium-cooled nuclear reactors.

Neutron absorbing room temperature vulcanizable silicone rubber compositions

DOEpatents

Zoch, Harold L.

1979-11-27

A neutron absorbing composition comprising a one-component room temperature vulcanizable silicone rubber composition or a two-component room temperature vulcanizable silicone rubber composition in which the composition contains from 25 to 300 parts by weight based on the base silanol or vinyl containing diorganopolysiloxane polymer of a boron compound or boron powder as the neutron absorbing ingredient. An especially useful boron compound in this application is boron carbide.

Development of large diameter carbon monofilament

NASA Technical Reports Server (NTRS)

Jacob, B.; Neltri, R. D.

1973-01-01

A process for preparing large diameter carbon-boron monofilament was developed. The process involves chemical vapor depositing a carbon-boron alloy monofilament from a BCl3, CH4, and H2 gas mixture onto a carbon substrate. Amorphous alloys were formed when gaseous mixtures containing greater than 20 percent methane (80 percent BCl3) were used. The longest uninterrupted lengths of carbon-boron monofilament were produced using a CH4/BCl3 gas ratio of 2.34. It was found that the properties of the carbon-boron alloy monofilament improved when the carbon substrate was precleaned in chlorine. The highest strength monofilament was attained when a CH4/BCl3 gas volume ratio of 0.44 was 28 million N/sq cm (40 million psi). While the highest strengths were attained in this run, the 0.44 gas ratio and other CH4/BCl3 ratios less than 2.34 would not yield long runs. Runs using these ratios were usually terminated because of a break in the monofilament within the reactor. It is felt better process control could probably be achieved by varying the amount of hydrogen; the BCl3/H2 ratio was kept constant in these studies.

Boron Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review

USGS Publications Warehouse

Eisler, R.

1990-01-01

Ecological and toxicological aspects of boron (B) in the environment are reviewed, with emphasis on natural resources. Subtopics covered include environmental chemistry, background concentrations, effects, and current recommendations for the protection of living resources. Boron is not now considered essential in mammalian nutrition, although low dietary levels protect against fluorosis and bone demineralization. Excessive consumption (i.e., >1,000 mg B/kg diet, >15 mg B/kg body weight daily, >1.0 mg B/L drinking water, or >210 mg B/kg body weight in a single dose) adversely affects growth, survival, or reproduction in sensitive mammals. Boron and its compounds are potent teratogens when applied directly to the mammalian embryo, but there is no evidence of mutagenicity or carcinogenicity. Boron`s unique affinity for cancerous tissues has been exploited in neutron capture radiation therapy of malignant human brain tumors. Current boron criteria recommended for the protection of sensitive species include <0.3 mg B/L in crop irrigation waters, <1.0 mg B/L for aquatic life, <5.0 mg B/L in livestock drinking waters, <30 mg B/kg in waterfowl diets, and <100 mg B/kg in livestock diets.

Boron supercapacitors

DOE PAGES

Zhan, Cheng; Zhang, Pengfei; Dai, Sheng; ...

2016-11-16

Supercapacitors based on the electric double-layer mechanism use porous carbons or graphene as electrodes. To move beyond this paradigm, we propose boron supercapacitors to leverage two-dimensional (2D) boron sheets’ metallicity and low weight. Six 2D boron sheets from both previous theoretical design and experimental growth are chosen as test electrodes. By applying joint density functional theory (JDFT) to the electrode–electrolyte system, we examine how the 2D boron sheets charge up against applied potential. JDFT predicts that these 2D boron sheets exhibit specific capacitance on the order of 400 F/g, about four times that of graphene. As a result, our workmore » suggests that 2D boron sheets are promising electrodes for supercapacitor applications.« less

Boron supercapacitors

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

Zhan, Cheng; Zhang, Pengfei; Dai, Sheng

Supercapacitors based on the electric double-layer mechanism use porous carbons or graphene as electrodes. To move beyond this paradigm, we propose boron supercapacitors to leverage two-dimensional (2D) boron sheets’ metallicity and low weight. Six 2D boron sheets from both previous theoretical design and experimental growth are chosen as test electrodes. By applying joint density functional theory (JDFT) to the electrode–electrolyte system, we examine how the 2D boron sheets charge up against applied potential. JDFT predicts that these 2D boron sheets exhibit specific capacitance on the order of 400 F/g, about four times that of graphene. As a result, our workmore » suggests that 2D boron sheets are promising electrodes for supercapacitor applications.« less

Fibrous refractory composite insulation. [shielding reusable spacecraft

NASA Technical Reports Server (NTRS)

Leiser, D. B.; Goldstein, H. E.; Smith, M. (Inventor)

1979-01-01

A refractory composite insulating material was prepared from silica fibers and aluminosilicate fibers in a weight ratio ranging from 1:19 to 19:1, and about 0.5 to 30% boron oxide, based on the total fiber weight. The aluminosilicate fiber and boron oxide requirements may be satisfied by using aluminoborosilicate fibers and, in such instances, additional free boron oxide may be incorporated in the mix up to the 30% limit. Small quantities of refractory opacifiers, such as silicon carbide, may be also added. The composites just described are characterized by the absence of a nonfibrous matrix.

Boron uptake in tumors, cerebrum and blood from [10B]NA4B24H22S2

DOEpatents

Slatkin, Daniel N.; Micca, Peggy L.; Fairchild, Ralph G.

1988-08-02

A stable boronated (.sup.10 B-labeled) compound, sodium mercaptoundecahydrododecaborate is infused in the form of the disulfide dimer, [.sup.10 B]Na.sub.4 B.sub.24 H.sub.22 S.sub.2, at a dose of about 200 .mu.g .sup.10 B per gm body weight. The infusion is performed into the blood or peritoneal cavity of the patient slowly over a period of many days, perhaps one week or more, at the rate of roughly 1 .mu.g .sup.10 B per gm body weight per hour. Use of this particular boronated dimer in the manner or similarly to the manner so described permits radiotherapeutically effective amounts of boron to accumulate in tumors to be treated by boron neutron capture radiation therapy and also permits sufficient retention of boron in tumor after the cessation of the slow infusion, so as to allow the blood concentration of .sup.10 B to drop or to be reduced artificially to a radiotherapeutically effective level, less than one-half of the concentration of .sup.10 B in the tumor.

Boron uptake in tumors, cerebrum and blood from [10B]NA4B24H22S2

DOEpatents

Slatkin, Daniel N.; Micca, Peggy L.; Fairchild, Ralph G.

1988-01-01

A stable boronated (.sup.10 B-labeled) compound, sodium mercaptoundecahydrododecaborate is infused in the form of the disulfide dimer, [.sup.10 B]Na.sub.4 B.sub.24 H.sub.22 S.sub.2, at a dose of about 200 .mu.g .sup.10 B per gm body weight. The infusion is performed into the blood or peritoneal cavity of the patient slowly over a period of many days, perhaps one week or more, at the rate of roughly 1 .mu.g .sup.10 B per gm body weight per hour. Use of this particular boronated dimer in the manner or similarly to the manner so described permits radiotherapeutically effective amounts of boron to accumulate in tumors to be treated by boron neutron capture radiation therapy and also permits sufficient retention of boron in tumor after the cessation of the slow infusion, so as to allow the blood concentration of .sup.10 B to drop or to be reduced artificially to a radiotherapeutically effective level, less than one-half of the concentration of .sup.10 B in the tumor.

Boron in Calcium Sulfate Vein at Catabola, Mars

NASA Image and Video Library

2016-12-13

The highest concentration of boron measured on Mars, as of late 2016, is in this mineral vein, called "Catabola," examined with the Chemistry and Camera (ChemCam) instrument on NASA's Curiosity rover on Aug, 25, 2016, during Sol 1441 of the mission. This two-part illustration shows the context of the erosion-resistant, raised vein, in an image from Curiosity's Mast Camera (Mastcam), and a detailed inset image from ChemCam's remote micro-imager. The inset includes indicators of the boron content measured at 10 points along the vein that were analyzed with ChemCam's laser-firing spectrometer. The vein's main component is calcium sulfate. The highest boron content identified is less than one-tenth of one percent. The heights of the orange bars at each point indicate relative abundance of boron, compared with boron content at other points. The scale bar for the inset is 9.2 millimeters, or about 0.36 inch. The ChemCam image is enhanced with color information from Mastcam. http://photojournal.jpl.nasa.gov/catalog/PIA21251

Assessment of boric acid and borax using the IEHR evaluative process for assessing human developmental and reproductive toxicity of agents

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

Moore, J.A.

This document presents an evaluation of the reproductive and developmental effects of boric acid, H3BO3 (CAS Registry No. 10043-35-3) and disodium tetraborate decahydrate or borax, Na2B4O2O(CAS Registry No. 1303-96-4). The element, boron, does not exist naturally. In dilute aqueous solution and at physiological pH (7.4), the predominant species in undissociated boric acid (greater than 98%), irrespective of whether the initial material was boric acid of borax. Therefore, it is both useful and correct to compare exposures and dosages to boric acid and borax in terms of `boron equivalents`, since both materials form equivalent species in dilute aqueous solution with similarmore » systemic effects. In order to be clear in this document, the term `boron` will refer to `boron equivalents` or percent boron in boric acid and borax.« less

Boron-copper neutron absorbing material and method of preparation

DOEpatents

Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry

1991-01-01

A composite, copper clad neutron absorbing material is comprised of copper powder and boron powder enriched with boron 10. The boron 10 content can reach over 30 percent by volume, permitting a very high level of neutron absorption. The copper clad product is also capable of being reduced to a thickness of 0.05 to 0.06 inches and curved to a radius of 2 to 3 inches, and can resist temperatures of 900.degree. C. A method of preparing the material includes the steps of compacting a boron-copper powder mixture and placing it in a copper cladding, restraining the clad assembly in a steel frame while it is hot rolled at 900.degree. C. with cross rolling, and removing the steel frame and further rolling the clad assembly at 650.degree. C. An additional sheet of copper can be soldered onto the clad assembly so that the finished sheet can be cold formed into curved shapes.

In Situ Detection of Boron by ChemCam on Mars

NASA Technical Reports Server (NTRS)

Gasda, Patrick J.; Haldeman, Ethan B.; Wiens, Roger C.; Rapin, William; Bristow, Thomas F.; Bridges, John C.; Schwenzer, Susanne P.; Clark, Benton; Herkenhoff, Kenneth; Frydenvang, Jens;

Boron sorption from aqueous solution by hydrotalcite and its preliminary application in geothermal water deboronation.

PubMed

Guo, Qinghai; Zhang, Yin; Cao, Yaowu; Wang, Yanxin; Yan, Weide

2013-11-01

Hydrotalcite and its calcination product were used to treat pure water spiked with various concentrations of boron and geothermal water containing boron as a major undesirable element. The kinetics process of boron sorption by uncalcined hydrotalcite is controlled by the diffusion of boron from bulk solution to sorbent-solution boundary film and its exchange with interlayer chloride of hydrotalcite, whereas the removal rate of boron by calcined hydrotalcite rests with the restoration process of its layered structure. The results of isotherm sorption experiments reveal that calcined hydrotalcite generally has much stronger ability to lower solution boron concentration than uncalcined hydrotalcite. The combination of adsorption of boron on the residue of MgO-Al2O3 solid solution and intercalation of boron into the reconstructed hydrotalcite structure due to "structural memory effect" is the basic mechanism based on which the greater boron removal by calcined hydrotalcite was achieved. As 15 geothermal water samples were used to test the deboronation ability of calcined hydrotalcite at 65 °C, much lower boron removal efficiencies were observed. The competitive sorption of the other anions in geothermal water, such as HCO3-, SO4(2-), and F-, is the reason why calcined hydrotalcite could not remove boron from geothermal water as effectively as from pure boron solution. However, boron removal percents ranging from 89.3 to 99.0% could be obtained if 50 times of sorbent were added to the geothermal water samples. Calcined hydrotalcite is a good candidate for deboronation of geothermal water.

Radiation resistant austenitic stainless steel alloys

DOEpatents

Maziasz, P.J.; Braski, D.N.; Rowcliffe, A.F.

1987-02-11

An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01 to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties. 4 figs.

Radiation resistant austenitic stainless steel alloys

DOEpatents

Maziasz, Philip J.; Braski, David N.; Rowcliffe, Arthur F.

1989-01-01

An austenitic stainless steel alloy, with improved resistance to radiation-induced swelling and helium embrittlement, and improved resistance to thermal creep at high temperatures, consisting essentially of, by weight percent: from 16 to 18% nickel; from 13 to 17% chromium; from 2 to 3% molybdenum; from 1.5 to 2.5% manganese; from 0.01 to 0.5% silicon; from 0.2 to 0.4% titanium; from 0.1 to 0.2% niobium; from 0.1 to 0.6% vanadium; from 0.06 to 0.12% carbon; from 0.01% to 0.03% nitrogen; from 0.03 to 0.08% phosphorus; from 0.005 to 0.01% boron; and the balance iron, and wherein the alloy may be thermomechanically treated to enhance physical and mechanical properties.

Spatial Burnout in Water Reactors with Nonuniform Startup Distributions of Uranium and Boron

NASA Technical Reports Server (NTRS)

Fox, Thomas A.; Bogart, Donald

1955-01-01

Spatial burnout calculations have been made of two types of water moderated cylindrical reactor using boron as a burnable poison to increase reactor life. Specific reactors studied were a version of the Submarine Advanced Reactor (sAR) and a supercritical water reactor (SCW) . Burnout characteristics such as reactivity excursion, neutron-flux and heat-generation distributions, and uranium and boron distributions have been determined for core lives corresponding to a burnup of approximately 7 kilograms of fully enriched uranium. All reactivity calculations have been based on the actual nonuniform distribution of absorbers existing during intervals of core life. Spatial burnout of uranium and boron and spatial build-up of fission products and equilibrium xenon have been- considered. Calculations were performed on the NACA nuclear reactor simulator using two-group diff'usion theory. The following reactor burnout characteristics have been demonstrated: 1. A significantly lower excursion in reactivity during core life may be obtained by nonuniform rather than uniform startup distribution of uranium. Results for SCW with uranium distributed to provide constant radial heat generation and a core life corresponding to a uranium burnup of 7 kilograms indicated a maximum excursion in reactivity of 2.5 percent. This compared to a maximum excursion of 4.2 percent obtained for the same core life when w'anium was uniformly distributed at startup. Boron was incorporated uniformly in these cores at startup. 2. It is possible to approach constant radial heat generation during the life of a cylindrical core by means of startup nonuniform radial and axial distributions of uranium and boron. Results for SCW with nonuniform radial distribution of uranium to provide constant radial heat generation at startup and with boron for longevity indicate relatively small departures from the initially constant radial heat generation distribution during core life. Results for SAR with a sinusoidal distribution rather than uniform axial distributions of boron indicate significant improvements in axial heat generation distribution during the greater part of core life. 3. Uranium investments for cylindrical reactors with nonuniform radial uranium distributions which provide constant radial heat generation per unit core volume are somewhat higher than for reactors with uniform uranium concentration at startup. On the other hand, uranium investments for reactors with axial boron distributions which approach constant axial heat generation are somewhat smaller than for reactors with uniform boron distributions at startup.

Boron uptake in tumors, cerebrum and blood from (/sup 10/B)Na/sub 4/B/sub 24/H/sub 22/S/sub 2/

DOEpatents

Slatkin, D.N.; Micca, P.L.; Fairchild, R.G.

1986-03-11

A stable boronated (/sup 10/B-labeled) compound, sodium mercaptoundecahydrododecaborate is infused in the form of the disulfide dimer, (/sup 10/B)Na/sub 4/B/sub 24/H/sub 22/S/sub 2/, at a dose of about 200 ..mu..g /sup 10/B per gm body weight. The infusion is preformed into the blood or peritoneal cavity of the patient slowly over a period of many days, perhaps one week or more, at the rate of roughly 1 ..mu..g /sup 10/B per gm body weight per hour. Use of this particular boronated dimer in the manner or similarly to the manner so described permits radiotherapeutically effective amounts of boron to accumulate in tumors to be treated by boron neutron capture radiation therapy and also permits sufficient retention of boron in tumor after the cessation of the slow infusion, so as to allow the blood concentration of /sup 10/B to drop or to be reduced artificially to a radiotherapeutically effective level, less than one-half of the concentration of /sup 10/B in the tumor. 1 tab.

Longitudinal residual stresses in boron fibers

NASA Technical Reports Server (NTRS)

Behrendt, D. R.

1976-01-01

A method of measuring the longitudinal residual stress distribution in boron fibers is presented. The residual stresses in commercial CVD boron on tungsten fibers of 102, 142, and 203 microns (4, 5.6, and 8 mil) diameters were determined. Results for the three sizes show a compressive stress at the surface 800 to -1400 MN/sq m 120 to -200 ksi), changing monotonically to a region of tensile stress within the boron. At approximately 25 percent of the original radius, the stress reaches a maximum tensile 600 to 1000 MN/sq m(90 to 150 ksi) and then decreases to compressive near the tungsten boride core. The core itself is under a compressive stress of approximately -1300 MN/sq m (-190 ksi). The effects of surface removal on core residual stress and core-initiated fracture are discussed.

Streamflow, dissolved solids, suspended sediment, and trace elements, San Joaquin River, California, June 1985-September 1988

USGS Publications Warehouse

Hill, B.R.; Gilliom, R.J.

1993-01-01

The 1985-88 study period included hydrologic extremes throughout most of central California. Except for an 11-month period during and after the 1986 flood, San Joaquin River streamflows during 1985-88 were generally less than median for 1975-88. The Merced Tuolumne, and Stanislaus Rivers together comprised 56 to 69 percent of the annual San Joaquin River flow, Salt and Mud Sloughs together comprised 6 to 19 percent, the upper San Joaquin River comprised 2 to 25 percent, and unmeasured sources from agricultural discharges and ground water accounted for 13 to 20 percent. Salt and Mud Sloughs and the unmeasured sources contribute most of the dissolved-solids load. The Merced, Tuolumne, and Stanislaus Rivers greatly dilute dissolved-solids concentrations. Suspended-sediment concentration peaked sharply at more than 600 milligrams per liter during the flood of February 1986. Concentrations and loads varied seasonally during low-flow conditions, with concentrations highest during the early summer irrigation season. Trace elements present primarily in dissolved phases are arsenic, boron, lithium, molybdenum, and selenium. Boron concentrations exceeded the irrigation water-quality criterion of 750 micrograms per liter more than 75 percent of the time in Salt and Mud Sloughs and more than 50 percent of the time at three sites on the San Joaquin River. Selenium concentrations exceeded the aquatic-life criterion of 5 micrograms per liter more than 75 percent of the time in Salt Slough and more than 50 percent of the time in Mud Slough and in the San Joaquin River from Salt Slough to the Merced River confluence. Concentrations of dissolved solids, boron, and selenium usually are highest during late winter to early spring, lower in early summer, higher again in mid-to-late summer, and the lowest in autumn, and generally correspond to seasonal inflows of subsurface tile-drain water to Salt and Mud Sloughs. Trace elements present primarily in particulate phases are aluminum, chromium, copper, iron, manganese, nickel, and zinc, none of which cause significant water-quality problems in the river.

Practical calculation method to estimate the absolute boron concentration in tissues using 18F-FBPA PET.

PubMed

Watabe, Tadashi; Hanaoka, Kohei; Naka, Sadahiro; Kanai, Yasukazu; Ikeda, Hayato; Aoki, Masanao; Shimosegawa, Eku; Kirihata, Mitsunori; Hatazawa, Jun

2017-07-01

The purpose of this study was to establish a practical method to estimate the absolute boron concentrations in the tissues based on the standardized uptake values (SUVs) after administration of 4-borono-phenylalanine (BPA) using 4-borono-2- 18 F-fluoro-phenylalanine ( 18 F-FBPA) PET. Rat xenograft models of C6 glioma (n = 7, body weight 241 ± 28.0 g) were used for the study. PET was performed 60 min after intravenous injection of 18 F-FBPA (30.5 ± 0.7 MBq). After the PET scanning, BPA-fructose (167.3 ± 18.65 mg/kg) was administered by slow intravenous injection to the same subjects. The rats were killed 60 min after the BPA injection and tissue samples were collected from the major organs and tumors. The absolute boron concentrations (unit: ppm) in the samples were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The boron concentrations in the tissues/tumors were also estimated from the 18 F-FBPA PET images using the following formula: estimated absolute boron concentration (ppm) = 0.0478 × [BPA dose (mg/kg)] × SUV. The measured absolute boron concentrations (mBC) by ICP-OES and the estimated boron concentrations (eBC) from the PET images were compared. The percent difference between the mBC and eBC calculated based on the SUV max was -5.2 ± 21.1% for the blood, -9.4 ± 22.3% for the brain, 1.6 ± 21.3% for the liver, -14.3 ± 16.8% for the spleen, -9.5 ± 27.5% for the pancreas, and 3.4 ± 43.2% for the tumor. Relatively large underestimation was observed for the lung (-48.4 ± 16.2%), small intestine (-37.8 ± 19.3%) and large intestine (-33.9 ± 11.0%), due to the partial volume effect arising from the air or feces contained in these organs. In contrast, relatively large overestimation was observed for the kidney (34.3 ± 29.3%), due to the influence of the high uptake in urine. The absolute boron concentrations in tissues/tumors can be estimated from the SUVs on 18 F-FBPA PET using a practical formula. Caution must be exercised in interpreting the estimated boron concentrations in the lung, small intestine and large intestine, to prevent the adverse effects of overexposure, which could occur due to underestimation by partial volume effect using PET.

Substrate for thin silicon solar cells

DOEpatents

Ciszek, Theodore F.

1995-01-01

A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1.times.10.sup.-3 ohm-cm.

Comparison between proton boron fusion therapy (PBFT) and boron neutron capture therapy (BNCT): a monte carlo study.

PubMed

Jung, Joo-Young; Yoon, Do-Kun; Barraclough, Brendan; Lee, Heui Chang; Suh, Tae Suk; Lu, Bo

2017-06-13

The aim of this study is to compare between proton boron fusion therapy (PBFT) and boron neutron capture therapy (BNCT) and to analyze dose escalation using a Monte Carlo simulation. We simulated a proton beam passing through the water with a boron uptake region (BUR) in MCNPX. To estimate the interaction between neutrons/protons and borons by the alpha particle, the simulation yielded with a variation of the center of the BUR location and proton energies. The variation and influence about the alpha particle were observed from the percent depth dose (PDD) and cross-plane dose profile of both the neutron and proton beams. The peak value of the maximum dose level when the boron particle was accurately labeled at the region was 192.4% among the energies. In all, we confirmed that prompt gamma rays of 478 keV and 719 keV were generated by the nuclear reactions in PBFT and BNCT, respectively. We validated the dramatic effectiveness of the alpha particle, especially in PBFT. The utility of PBFT was verified using the simulation and it has a potential for application in radiotherapy.

Comparison between proton boron fusion therapy (PBFT) and boron neutron capture therapy (BNCT): a Monte Carlo study

PubMed Central

Barraclough, Brendan; Lee, Heui Chang; Suh, Tae Suk; Lu, Bo

2017-01-01

The aim of this study is to compare between proton boron fusion therapy (PBFT) and boron neutron capture therapy (BNCT) and to analyze dose escalation using a Monte Carlo simulation. We simulated a proton beam passing through the water with a boron uptake region (BUR) in MCNPX. To estimate the interaction between neutrons/protons and borons by the alpha particle, the simulation yielded with a variation of the center of the BUR location and proton energies. The variation and influence about the alpha particle were observed from the percent depth dose (PDD) and cross-plane dose profile of both the neutron and proton beams. The peak value of the maximum dose level when the boron particle was accurately labeled at the region was 192.4% among the energies. In all, we confirmed that prompt gamma rays of 478 keV and 719 keV were generated by the nuclear reactions in PBFT and BNCT, respectively. We validated the dramatic effectiveness of the alpha particle, especially in PBFT. The utility of PBFT was verified using the simulation and it has a potential for application in radiotherapy. PMID:28427153

Evaluation of a metal shear web selectively reinforced with filamentary composites for space shuttle application. Phase 1 summary report: Shear web design development

NASA Technical Reports Server (NTRS)

Laakso, J. H.; Zimmerman, D. K.

1972-01-01

An advanced composite shear web design concept was developed for the Space Shuttle orbiter main engine thrust beam structure. Various web concepts were synthesized by a computer-aided adaptive random search procedure. A practical concept is identified having a titanium-clad + or - 45 deg boron/epoxy web plate with vertical boron/epoxy reinforced aluminum stiffeners. The boron-epoxy laminate contributes to the strength and stiffness efficiency of the basic web section. The titanium-cladding functions to protect the polymeric laminate parts from damaging environments and is chem-milled to provide reinforcement in selected areas. Detailed design drawings are presented for both boron/epoxy reinforced and all-metal shear webs. The weight saving offered is 24% relative to all-metal construction at an attractive cost per pound of weight saved, based on the detailed designs. Small scale element tests substantiate the boron/epoxy reinforced design details in critical areas. The results show that the titanium-cladding reliably reinforces the web laminate in critical edge load transfer and stiffener fastener hole areas.

Tensile stress-strain behavior of boron/aluminum laminates

NASA Technical Reports Server (NTRS)

Sova, J. A.; Poe, C. C., Jr.

1978-01-01

The tensile stress-strain behavior of five types of boron/aluminum laminates was investigated. Longitudinal and transverse stress-strain curves were obtained for monotonic loading to failure and for three cycles of loading to successively higher load levels. The laminate strengths predicted by assuming that the zero deg plies failed first correlated well with the experimental results. The stress-strain curves for all the boron/aluminum laminates were nonlinear except at very small strains. Within the small linear regions, elastic constants calculated from laminate theory corresponded to those obtained experimentally to within 10 to 20 percent. A limited amount of cyclic loading did not affect the ultimate strength and strain for the boron/aluminum laminates. The laminates, however, exhibited a permanent strain on unloading. The Ramberg-Osgood equation was fitted to the stress-strain curves to obtain average curves for the various laminates.

Axial residual stresses in boron fibers

NASA Technical Reports Server (NTRS)

Behrendt, D. R.

1978-01-01

The axial residual stress distribution as a function of radius was determined from the fiber surface to the core including the average residual stress in the core. Such measurements on boron on tungsten (B/W) fibers show that the residual stresses for 102, 142, 203, and 366 micron diameter fibers were similar, being compressive at the surface and changing monotonically to a region of tensile within the boron. At approximately 25 percent of the original radius, the stress reaches a maximum tensile stress of about 860 mn/sq.m and then decreases to a compressive stress near the tungsten boride core. Data were presented for 203 micron diameter B/W fibers that show annealing above 900 C reduces the residual stresses. A comparison between 102 micron diameter B/W and boron on carbon (b/C) shows that the residual stresses were similar in the outer regions of the fibers, but that large differences near and in the core were observed. The effects of these residual stresses on the fracture of boron fibers were discussed.

Hydrogen adsorption capacities of multi-walled boron nitride nanotubes and nanotube arrays: a grand canonical Monte Carlo study.

PubMed

Ahadi, Zohreh; Shadman, Muhammad; Yeganegi, Saeed; Asgari, Farid

2012-07-01

Hydrogen adsorption in multi-walled boron nitride nanotubes and their arrays was studied using grand canonical Monte Carlo simulation. The results show that hydrogen storage increases with tube diameter and the distance between the tubes in multi-walled boron nitride nanotube arrays. Also, triple-walled boron nitride nanotubes present the lowest level of hydrogen physisorption, double-walled boron nitride nanotubes adsorb hydrogen better when the diameter of the inner tube diameter is sufficiently large, and single-walled boron nitride nanotubes adsorb hydrogen well when the tube diameter is small enough. Boron nitride nanotube arrays adsorb hydrogen, but the percentage of adsorbed hydrogen (by weight) in boron nitride nanotube arrays is rather similar to that found in multi-walled boron nitride nanotubes. Also, when the Langmuir and Langmuir-Freundlich equations were fitted to the simulated data, it was found that multi-layer adsorptivity occurs more prominently as the number of walls and the tube diameter increase. However, in single-walled boron nitride nanotubes with a small diameter, the dominant mechanism is monolayer adsorptivity.

Substrate for thin silicon solar cells

DOEpatents

Ciszek, T.F.

1995-03-28

A photovoltaic device for converting solar energy into electrical signals comprises a substrate, a layer of photoconductive semiconductor material grown on said substrate, wherein the substrate comprises an alloy of boron and silicon, the boron being present in a range of from 0.1 to 1.3 atomic percent, the alloy having a lattice constant substantially matched to that of the photoconductive semiconductor material and a resistivity of less than 1{times}10{sup {minus}3} ohm-cm. 4 figures.

Wettability of Pyrolytic Boron Nitride by Aluminum

NASA Technical Reports Server (NTRS)

Chiaramonte, Francis P.; Rosenthal, Bruce N.

1991-01-01

The wetting of pyrolytic boron nitride by molten 99.9999 percent pure aluminum was investigated by using the sessile drop method in a vacuum operating at approximately 660 micro-Pa at temperatures ranging from 700 to 1000 C. The equilibrium contact angle decreased with an increase in temperature. For temperatures at 900 C or less, the equilibrium contact angle was greater than 90 deg. At 1000 C a nonwetting-to-wetting transition occurred and the contact angle stabilized at 49 deg.

Chemical quality of ground water in San Joaquin and part of Contra Costa Counties, California

USGS Publications Warehouse

Sorenson, Stephen K.

1981-01-01

Chemical water-quality conditions were investigated in San Joaquin and part of Contra Costa Counties by canvassing available wells and sampling water from 324 representative wells. Chemical water types varied, with 73 percent of the wells sampled containing either calcium-magnesium bicarbonate, or calcium-sodium bicarbonate type water. Substantial areas contain ground water exceeding water-quality standards for boron, manganese, and nitrate. Trace elements, with the exception of boron and manganese, were present in negligible amounts. (USGS)

Effects of hexagonal boron nitride on dry compression mixture of Avicel DG and Starch 1500.

PubMed

Uğurlu, Timuçin; Halaçoğlu, Mekin Doğa

2016-01-01

The objective of this study was to investigate the lubrication properties of hexagonal boron nitride (HBN) on a (1:1) binary mixture of Avicel DG and Starch 1500 after using the dry granulation-slugging method and compare it with conventional lubricants, such as magnesium stearate (MGST), glyceryl behenate (COMP) and stearic acid (STAC). MGST is one of the most commonly used lubricants in the pharmaceutical industry. However, it has several adverse effects on tablet properties. In our current study, we employed various methods to eradicate the work hardening phenomenon in dry granulation, and used HBN as a new lubricant to overcome the adverse effects of other lubricants on tablet properties. HBN was found to be as effective as MGST and did not show any significant adverse effects on the crushing strength or work hardening. From the scanning electron microscope (SEM) images, it was concluded that HBN distributed better than MGST. As well as showing better distribution, HBN's effect on disintegration was the least pronounced. Semi-quantitative weight percent distribution of B and N elements in the tablets was obtained using EDS (energy dispersive spectroscopy). Based on atomic force microscope (AFM) surface roughness images, formulations prepared with 1% HBN showed better plastic character than those prepared with MGST.

Study of Crystallographic Texture During Thermo-Mechanical Processing of Boron Modified Ti-Alloys

DTIC Science & Technology

2009-07-15

project developed a processing strategy for boron-modified titanium alloy Ti- 6Al - 4V , and developed an understanding of the deformation and...develop the processing strategy for boron modified titanium alloy Ti- 6Al - 4V 2. To understand the deformation and transformation mechanisms as a function...strength-to-weight ratio, excellent mechanical properties and corrosion resistance, titanium (Ti) and its alloys, especially (α+β) alloys like Ti- 6Al - 4V

Boron modified molybdenum silicide and products

DOEpatents

Meyer, M.K.; Akinc, M.

1999-02-02

A boron-modified molybdenum silicide material is disclosed having the composition comprising about 80 to about 90 weight % Mo, about 10 to about 20 weight % Si, and about 0.1 to about 2 weight % B and a multiphase microstructure including Mo{sub 5}Si{sub 3} phase as at least one microstructural component effective to impart good high temperature creep resistance. The boron-modified molybdenum silicide material is fabricated into such products as electrical components, such as resistors and interconnects, that exhibit oxidation resistance to withstand high temperatures in service in air as a result of electrical power dissipation, electrical resistance heating elements that can withstand high temperatures in service in air and other oxygen-bearing atmospheres and can span greater distances than MoSi{sub 2} heating elements due to improved creep resistance, and high temperature structural members and other fabricated components that can withstand high temperatures in service in air or other oxygen-bearing atmospheres while retaining creep resistance associated with Mo{sub 5}Si{sub 3} for structural integrity. 7 figs.

Boron modified molybdenum silicide and products

DOEpatents

Meyer, Mitchell K.; Akinc, Mufit

1999-02-02

A boron-modified molybdenum silicide material having the composition comprising about 80 to about 90 weight % Mo, about 10 to about 20 weight % Si, and about 0.1 to about 2 weight % B and a multiphase microstructure including Mo.sub.5 Si.sub.3 phase as at least one microstructural component effective to impart good high temperature creep resistance. The boron-modified molybdenum silicide material is fabricated into such products as electrical components, such as resistors and interconnects, that exhibit oxidation resistance to withstand high temperatures in service in air as a result of electrical power dissipation, electrical resistance heating elements that can withstand high temperatures in service in air and other oxygen-bearing atmospheres and can span greater distances than MoSi.sub.2 heating elements due to improved creep resistance, and high temperature structural members and other fabricated components that can withstand high temperatures in service in air or other oxygen-bearing atmospheres while retaining creep resistance associated with Mo.sub.5 Si.sub.3 for structural integrity.

Completion of evaluation of manufacturing processes for B/Al composites containing 0.2mm diameter boron fibers

NASA Technical Reports Server (NTRS)

Moore, T. J.; Moorhead, P. E.

1980-01-01

Four fabricators produced a total of 54 B/1100 Al, B/6061 Al, and B/2024 Al panels for evaluation. The 8 ply unidirectional, 45 to 50 volume percent, panels were made using 0.20 mm diameter boron fibers which were obtained from a single supplier. Hot press consolidation was carried out in vacuum except for one set of dry woven tape panels which were hot pressed in air. A single testing contractor conducted nondestructive inspection, metallography, fractography and mechanical property tests. The mechanical property tests included 21 and 260 C tensile tests and 21 C shear tests. Panel quality, as measured by nondestructive evaluation, was generally good as were the 21 C tensile properties. The panels hot pressed in air delaminated in the shear tests. Shear strength values were lower in these panels. But tensile strengths were not affected by the delaminations because of the relation between the tensile loading direction and the delaminations. Composite tensile strength was found to be proportional to the volume percent boron and the aluminum matrix rather than to the tape used or fabrication technique. Suitability of these composites for 260 C service was confirmed by tensile tests.

Arsenic, Boron, and Fluoride Concentrations in Ground Water in and Near Diabase Intrusions, Newark Basin, Southeastern Pennsylvania

USGS Publications Warehouse

Senior, Lisa A.; Sloto, Ronald A.

2006-01-01

During an investigation in 2000 by the U.S. Environmental Protection Agency (USEPA) of possible contaminant releases from an industrial facility on Congo Road near Gilbertsville in Berks and Montgomery Counties, southeastern Pennsylvania, concentrations of arsenic and fluoride above USEPA drinking-water standards of 10 ?g/L and 4 mg/L, respectively, and of boron above the USEPA health advisory level of 600 ?g/L were measured in ground water in an area along the northwestern edge of the Newark Basin. In 2003, the USEPA requested technical assistance from the U.S. Geological Survey (USGS) to help identify sources of arsenic, boron, and fluoride in the ground water in the Congo Road area, which included possible anthropogenic releases and naturally occurring mineralization in the local bedrock aquifer, and to identify other areas in the Newark Basin of southeastern Pennsylvania with similarly elevated concentrations of these constituents. The USGS reviewed available data and collected additional ground-water samples in the Congo Road area and four similar hydrogeologic settings. The Newark Basin is the largest of the 13 major exposed Mesozoic rift basins that stretch from Nova Scotia to South Carolina. Rocks in the Newark Basin include Triassic through Jurassic-age sedimentary sequences of sandstones and shales that were intruded by diabase. Mineral deposits of hydrothermal origin are associated with alteration zones bordering intrusions of diabase and also occur as strata-bound replacement deposits of copper and zinc in sedimentary rocks. The USGS review of data available in 2003 showed that water from about 10 percent of wells throughout the Newark Basin of southeastern Pennsylvania had concentrations of arsenic greater than the USEPA maximum contaminant level (MCL) of 10 ?g/L; the highest reported arsenic concentration was at about 70 ?g/L. Few data on boron were available, and the highest reported boron concentration in well-water samples was 60 ?g/L in contrast to concentrations over 5,000 ?g/L in the Congo Road area. Although concentrations of fluoride up to 4 mg/L were reported for a few well-water samples collected throughout the Newark Basin, about 90 percent of the samples had concentrations of 0.5 mg/L or less. The USGS sampled 58 wells primarily in 5 areas in the Newark Basin, southeastern Pennsylvania, from February 2004 through April 2005 to identify other possible areas of elevated arsenic, boron, and fluoride and to characterize the geochemical environment associated with elevated concentrations of these constituents. Sampled wells included 12 monitor wells at an industrial facility near Congo Road, 45 private-supply wells in Berks, Montgomery, and Bucks Counties, and 1 private-supply well near Dillsburg, York County, an area where elevated fluoride in ground water had been reported in the adjacent Gettysburg Basin. Wells were sampled in transects from the diabase through the adjacent hornfels and into the unaltered shales of the Brunswick Group. Field measurements were made of pH, temperature, dissolved oxygen concentration, and specific conductance. Samples were analyzed in the laboratory for major ions, nutrients, total organic carbon, dissolved and total concentrations of selected trace elements, and boron isotopic composition. Generally, the ground water from the 46 private-supply wells had relatively neutral to alkaline pH (ranging from 6.1 to 9.1) and moderate concentrations of dissolved oxygen. Most water samples were of the calcium-bicarbonate type. Concentrations of arsenic up to 60 ?g/L, boron up to 3,950 ?g/L, and fluoride up to 0.70 mg/L were measured. Drinking-water standards or health advisories (for constituents that do not have standards established) were exceeded most frequently (about 20 percent of samples) for arsenic and boron and less frequently (6 percent or less of samples) for total iron, manganese, sulfate, nitrate, lead, molybdenum, and strontium. In water from 12 monitor

Stable isotope ratio mass spectrometry of nanogram quantities of boron and sulfur

NASA Astrophysics Data System (ADS)

Wieser, Michael Eugene

1998-09-01

Instrumentation and analytical techniques were developed to measure isotope abundances from nanograms of sulfur and boron. Sulfur isotope compositions were determined employing continuous flow isotope ratio mass spectroscopy (CF-IRMS) procedures and AsS+ thermal ionization mass spectrometry techniques (AsS+-TIMS). Boron isotope abundances were determined by BO2/sp--TIMS. CF-IRMS measurements realized δ34S values from 10 μg sulfur with precisions of ±0.3/perthous. To extend sulfur isotope measurements to much smaller samples, a TIMS procedure was developed to measure 75As32S+ and 75As34S+ at masses 108 and 109 from 200 ng S on a Finnigan MAT 262 with an ion counter. This is possibly the smallest amount of sulfur which has been successfully analyzed isotopically. The internal precision of 32S/34S ratios measured by AsS+-TIMS was better than ±0.15 percent. δ34S-values calculated relative to the measured 32S/34S value of an IAEA AG2S standard (S-1) agreed with those determined by CF-IRMS to within ±3/perthous. The increasing sensitivity of S-isotope analyses permits hiterto impossible investigations e.g. sulfur in tree rings and ice cores. Boron isotope abundances were measured as BO2/sp- from 50 ng B using an older thermal ionization mass spectrometer which had been extensively upgraded including the addition of computer control electronics, sensitive ion current amplification and fiber optic data bus. The internal precisions of the measured 11B/10B ratios were ±0.15 percent and the precisions of δ11B values calculated relative to the accepted international standard (SRM-951) were ±3/perthous. Two applications of boron isotope abundance variations were initiated (1) ground waters of Northern Alberta and (2) coffee beans in different regions of the world. In the first it was demonstrated that boron isotopes could be used to trace boron released during steam injection of oil sands into the surrounding environment. Data from the second study suggest that boron isotopes can be used to improve cultivation of coffee particularly in regions where 'organically grown' coffee had markedly different δ11B values than beans grown with boron- containing fertilizers in neighbouring regions. A regional dependence on the δ11B values of the coffee allow the sources of commercial coffee blends to be identified.

Investigation of Isotopically Tailored Boron in Advanced Fission and Fusion Reactor Systems.

NASA Astrophysics Data System (ADS)

Domaszek, Gerald Raymond

This research examines the use of B^ {11}, in the form of metallic boron and boron carbide, as a moderating and reflecting material. An examination of the neutronic characteristics of the B ^{11} isotope of boron has revealed that B^{11} has neutron scattering and absorption cross sections favorably comparable to those of Be^9 and C^ {12}. Preliminary analysis of the neutronics of B ^{11} were performed by conducting one dimensional transport calculations on an infinite slab of varying thickness. Beryllium is the best of the three materials in reflecting neutrons due primarily to the contribution from (n,2n) reactions. Tailored neutron energy beam transmission experiments were carried out to experimentally verify the predicted neutronic characteristics of B^{11 }. To further examine the neutron moderating and reflecting characteristics of B^{11 }, the energy dependent neutron flux was measured as a function of position in an exponential pile constructed of B_4C isotopically enriched to 98.5 percent B^{11}. After the experimental verification of the neutronic behavior of B^{11}, further design studies were conducted using metallic boron and boron carbide enriched in the B^{11 } isotope. The use of materials isotopically enriched in B^{11} as a liner in the first wall/blanket of a magnetic confinement fusion reactor demonstrated acceptable tritium regeneration in the lithium blanket. Analysis of the effect of contaminant levels of B^{10} showed that B^{10} contents of less than 1 percent in metallic boron produced negligible adverse effects on the tritium breeding. A comparison of the effectiveness of graphite and B^{11}_4C when used as moderators in a reactor fueled with natural uranium has shown that the maximum k_infty for a given fuel rod design is approximately the same for both materials. Approximately half the volume of the moderator is required when B^{11 }_4C is substituted for graphite to obtain essentially the same K_infty . An analysis of the effectiveness of various materials as reflector control elements for a compact space reactor has shown that B^{11} is neutronically superior to graphite in these applications. Metallic boron and boron carbide isotopically enriched in B^{11} have been demonstrated to be neutronically acceptable for varied applications in advanced reactor systems. B^ {11} has been shown to be superior in performance to graphite. While only somewhat inferior to beryllium as neutron multipliers, B^ {11} and B^{11} _4C have safety, supply and cost advantage over beryllium. (Abstract shortened with permission of author.).

Use of boron waste as an additive in red bricks

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

Uslu, T.; Arol, A.I

2004-07-01

In boron mining and processing operations, large amounts of clay containing tailings have to be discarded. Being rich in boron, the tailings do not only cause economical loss but also pose serious environmental problems. Large areas have to be allocated for waste disposal. In order to alleviate this problem, the possibility of using clayey tailings from a borax concentrator in red brick manufacturing was investigated. Up to 30% by weight tailings addition was found to improve the brick quality.

Termite Resistance of MDF Panels Treated with Various Boron Compounds

PubMed Central

Usta, Mustafa; Ustaomer, Derya; Kartal, Saip Nami; Ondaral, Sedat

2009-01-01

In this study, the effects of various boron compounds on the termite resistance of MDF panels were evaluated. Either borax (BX), boric acid (BA), zinc borate (ZB), or sodium perborate tetrahydrate (SPT) were added to urea-formaldehyde (UF) resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH4Cl. MDF samples from the panels were tested against the subterranean termites, Coptotermes formosanus Shiraki. Laboratory termite resistance tests showed that all samples containing boron compounds had greater resistance against termite attack compared to untreated MDF samples. At the second and third weeks of exposure, nearly 100% termite mortalities were recorded in all boron compound treated samples. The highest termite mortalities were determined in the samples with either BA or BX. Also, it was found that SPT showed notable performance on the termite mortality. As chemical loadings increased, termite mortalities increased, and at the same time the weight losses of the samples decreased. PMID:19582229

Concentration comparison of selected constituents between groundwater samples collected within the Missouri River alluvial aquifer using purge and pump and grab-sampling methods, near the city of Independence, Missouri, 2013

USGS Publications Warehouse

Krempa, Heather M.

2015-10-29

Relative percent differences between methods were greater than 10 percent for most analyzed trace elements. Barium, cobalt, manganese, and boron had concentrations that were significantly different between sampling methods. Barium, molybdenum, boron, and uranium method concentrations indicate a close association between pump and grab samples based on bivariate plots and simple linear regressions. Grab sample concentrations were generally larger than pump concentrations for these elements and may be because of using a larger pore sized filter for grab samples. Analysis of zinc blank samples suggests zinc contamination in filtered grab samples. Variations of analyzed trace elements between pump and grab samples could reduce the ability to monitor temporal changes and potential groundwater contamination threats. The degree of precision necessary for monitoring potential groundwater threats and application objectives need to be considered when determining acceptable variation amounts.

Boron exposure through drinking water during pregnancy and birth size.

PubMed

Igra, Annachiara Malin; Harari, Florencia; Lu, Ying; Casimiro, Esperanza; Vahter, Marie

2016-10-01

Boron is a metalloid found at highly varying concentrations in soil and water. Experimental data indicate that boron is a developmental toxicant, but the few human toxicity data available concern mostly male reproduction. To evaluate potential effects of boron exposure through drinking water on pregnancy outcomes. In a mother-child cohort in northern Argentina (n=194), 1-3 samples of serum, whole blood and urine were collected per woman during pregnancy and analyzed for boron and other elements to which exposure occurred, using inductively coupled plasma mass spectrometry. Infant weight, length and head circumference were measured at birth. Drinking water boron ranged 377-10,929μg/L. The serum boron concentrations during pregnancy ranged 0.73-605μg/L (median 133μg/L) and correlated strongly with whole-blood and urinary boron, and, to a lesser extent, with water boron. In multivariable-adjusted linear spline regression analysis (non-linear association), we found that serum boron concentrations above 80μg/L were inversely associated with birth length (B-0.69cm, 95% CI -1.4; -0.024, p=0.043, per 100μg/L increase in serum boron). The impact of boron appeared stronger when we restricted the exposure to the third trimester, when the serum boron concentrations were the highest (0.73-447μg/L). An increase in serum boron of 100μg/L in the third trimester corresponded to 0.9cm shorter and 120g lighter newborns (p=0.001 and 0.021, respectively). Considering that elevated boron concentrations in drinking water are common in many areas of the world, although more screening is warranted, our novel findings warrant additional research on early-life exposure in other populations. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Clarifying Atomic Weights: A 2016 Four-Figure Table of Standard and Conventional Atomic Weights

ERIC Educational Resources Information Center

Coplen, Tyler B.; Meyers, Fabienne; Holden, Norman E.

2017-01-01

To indicate that atomic weights of many elements are not constants of nature, in 2009 and 2011 the Commission on Isotopic Abundances and Atomic Weights (CIAAW) of the International Union of Pure and Applied Chemistry (IUPAC) replaced single-value standard atomic weight values with atomic weight intervals for 12 elements (hydrogen, lithium, boron,…

High Purity and Yield of Boron Nitride Nanotubes Using Amorphous Boron and a Nozzle-Type Reactor

PubMed Central

Kim, Jaewoo; Seo, Duckbong; Yoo, Jeseung; Jeong, Wanseop; Seo, Young-Soo; Kim, Jaeyong

2014-01-01

Enhancement of the production yield of boron nitride nanotubes (BNNTs) with high purity was achieved using an amorphous boron-based precursor and a nozzle-type reactor. Use of a mixture of amorphous boron and Fe decreases the milling time for the preparation of the precursor for BNNTs synthesis, as well as the Fe impurity contained in the B/Fe interdiffused precursor nanoparticles by using a simple purification process. We also explored a nozzle-type reactor that increased the production yield of BNNTs compared to a conventional flow-through reactor. By using a nozzle-type reactor with amorphous boron-based precursor, the weight of the BNNTs sample after annealing was increased as much as 2.5-times with much less impurities compared to the case for the flow-through reactor with the crystalline boron-based precursor. Under the same experimental conditions, the yield and quantity of BNNTs were estimated as much as ~70% and ~1.15 g/batch for the former, while they are ~54% and 0.78 g/batch for the latter. PMID:28788161

High Purity and Yield of Boron Nitride Nanotubes Using Amorphous Boron and a Nozzle-Type Reactor.

PubMed

Kim, Jaewoo; Seo, Duckbong; Yoo, Jeseung; Jeong, Wanseop; Seo, Young-Soo; Kim, Jaeyong

2014-08-11

Enhancement of the production yield of boron nitride nanotubes (BNNTs) with high purity was achieved using an amorphous boron-based precursor and a nozzle-type reactor. Use of a mixture of amorphous boron and Fe decreases the milling time for the preparation of the precursor for BNNTs synthesis, as well as the Fe impurity contained in the B/Fe interdiffused precursor nanoparticles by using a simple purification process. We also explored a nozzle-type reactor that increased the production yield of BNNTs compared to a conventional flow-through reactor. By using a nozzle-type reactor with amorphous boron-based precursor, the weight of the BNNTs sample after annealing was increased as much as 2.5-times with much less impurities compared to the case for the flow-through reactor with the crystalline boron-based precursor. Under the same experimental conditions, the yield and quantity of BNNTs were estimated as much as ~70% and ~1.15 g/batch for the former, while they are ~54% and 0.78 g/batch for the latter.

Strength advantages of chemically polished boron fibers before and after reaction with aluminum

NASA Technical Reports Server (NTRS)

Dicarlo, J. A.; Smith, R. J.

1982-01-01

In order to determine their strength potential, the fracture properties of different types of commercial boron fibers were measured before and after application of secondary strengthening treatments. The principal treatments employed were a slight chemical polish, which removed low strength surface flaws, and a heat treatment in oxygen, which contracted the fibers and thereby compressed intrinsic bulk flaws. Those fiber types most significantly strengthened were 200 to 400 micrometers (8 to 16 mil) diameter boron on tungsten fibers produced in a single chemical vapor deposition reactor. The slight polish increased average tensile strenghts from 3.4 to 4.4 CN/m2 (500 to 640 ksi) and reduced coefficients of variation from about 15 to 3 percent. The oxygen heat treatment plus slight polish further improved average strengths to 5.5 GN/m2 (800 ksi) with coefficients near 3 percent. To ascertain whether these excellent properties could be retained after fabrication of B/Al composites, as produced and polished 203 micrometers (8 mil) fibers were thinly coated with aluminum, heat treated at B/Al fabrication temperatures, and then tested in tension and flexure at room temperature. The pre-polished fibers were observed to retain their superior strengths to higher temperatures than the as-produced fibers even though both were subjected to the same detrimental reaction with aluminum.

Heat and corrosion resistant cast CF8C stainless steel with improved high temperature strength and ductility

DOEpatents

Maziasz, Philip J.; McGreevy, Tim; Pollard, Michael James; Siebenaler, Chad W.; Swindeman, Robert W.

2006-12-26

A CF8C type stainless steel alloy and articles formed therefrom containing about 18.0 weight percent to about 22.0 weight percent chromium and 11.0 weight percent to about 14.0 weight percent nickel; from about 0.05 weight percent to about 0.15 weight percent carbon; from about 2.0 weight percent to about 10.0 weight percent manganese; and from about 0.3 weight percent to about 1.5 weight percent niobium. The present alloys further include less than 0.15 weight percent sulfur which provides high temperature strength both in the matrix and at the grain boundaries without reducing ductility due to cracking along boundaries with continuous or nearly-continuous carbides. The disclosed alloys also have increased nitrogen solubility thereby enhancing strength at all temperatures because nitride precipitates or nitrogen porosity during casting are not observed. The solubility of nitrogen is dramatically enhanced by the presence of manganese, which also retains or improves the solubility of carbon thereby providing additional solid solution strengthening due to the presence of manganese and nitrogen, and combined carbon.

Heat and corrosion resistant cast CF8C stainless steel with improved high temperature strength and ductility

DOEpatents

Maziasz, Philip J.; McGreevy, Tim; Pollard, Michael James; Siebenaler, Chad W.; Swindeman, Robert W.

2010-08-17

A CF8C type stainless steel alloy and articles formed therefrom containing about 18.0 weight percent to about 22.0 weight percent chromium and 11.0 weight percent to about 14.0 weight percent nickel; from about 0.05 weight percent to about 0.15 weight percent carbon; from about 2.0 weight percent to about 10.0 weight percent manganese; and from about 0.3 weight percent to about 1.5 weight percent niobium. The present alloys further include less than 0.15 weight percent sulfur which provides high temperature strength both in the matrix and at the grain boundaries without reducing ductility due to cracking along boundaries with continuous or nearly-continuous carbides. The disclosed alloys also have increased nitrogen solubility thereby enhancing strength at all temperatures because nitride precipitates or nitrogen porosity during casting are not observed. The solubility of nitrogen is dramatically enhanced by the presence of manganese, which also retains or improves the solubility of carbon thereby providing additional solid solution strengthening due to the presence of manganese and nitrogen, and combined carbon.

Carbon or boron modified titanium silicide

DOEpatents

Thom, A.J.; Akinc, M.

1998-07-14

A titanium silicide material based on Ti{sub 5}Si{sub 3} intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000 C. Boron is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end. 3 figs.

Carbon or boron modified titanium silicide

DOEpatents

Thom, A.J.; Akinc, M.

1997-12-02

A titanium silicide material based on Ti{sub 5}Si{sub 3} intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000 C. Boron is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end. 3 figs.

Carbon or boron modified titanium silicide

DOEpatents

Thom, Andrew J.; Akinc, Mufit

1996-12-03

A titanium silicide material based on Ti.sub.5 Si.sub.3 intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000.degree. C. Boron is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end.

Carbon or boron modified titanium silicide

DOEpatents

Thom, Andrew J.; Akinc, Mufit

1997-12-02

A titanium silicide material based on Ti.sub.5 Si.sub.3 intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000.degree. C. Boron is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end.

Carbon or boron modified titanium silicide

DOEpatents

Thom, A.J.; Akinc, M.

1996-12-03

A titanium silicide material based on Ti{sub 5}Si{sub 3} intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000 C. Boron is added to a Ti{sub 5}Si{sub 3} base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end. 3 figs.

Carbon or boron modified titanium silicide

DOEpatents

Thom, Andrew J.; Akinc, Mufit

1998-07-14

A titanium silicide material based on Ti.sub.5 Si.sub.3 intermetallic compound exhibits substantially improved oxidative stability at elevated temperatures. In particular, carbon is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.6 weight % C) effective to impart substantially improved oxidative stability at elevated temperatures, such as about 1000.degree. C. Boron is added to a Ti.sub.5 Si.sub.3 base material in an amount (e.g. about 0.3 to about 3.3 weight % B) to this same end.

Reversible hydrogen storage materials

DOEpatents

Ritter, James A [Lexington, SC; Wang, Tao [Columbia, SC; Ebner, Armin D [Lexington, SC; Holland, Charles E [Cayce, SC

2012-04-10

In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential.

PubMed

Heber, Elisa M; Kueffer, Peter J; Lee, Mark W; Hawthorne, M Frederick; Garabalino, Marcela A; Molinari, Ana J; Nigg, David W; Bauer, William; Hughes, Andrea Monti; Pozzi, Emiliano C C; Trivillin, Verónica A; Schwint, Amanda E

2012-05-01

Boron neutron capture therapy (BNCT) combines selective accumulation of (10)B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1) MAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na(3) [ae-B(20)H(17)NH(3)], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 ± 16.1 ppm at 48 h and to 43.9 ± 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.

Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential

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

David W. Nigg

2012-05-01

Boron neutron capture therapy (BNCT) combines selective accumulation of 10B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1)more » MAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na3 [ae-B20H17NH3], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 {+-} 16.1 ppm at 48 h and to 43.9 {+-} 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.« less

Improved Ablative Materials

DTIC Science & Technology

1967-12-01

Equipment 62 2. Gas Analysis 62 3. Chemical Analysis for Titanium and Boron 63 4. Tensile Strength Determinations 64 5. Density Determinations 64 6. X-ray...mils, and its density was about 4. 45 g/cm 3. Elastic modulus values averaged about 71 x 106 psi for the filament. -X- I. INTRODUCTION Ablative liner...20 4 /50 percent N 2H 4 -50 percent UDMH or L0 2 /LH. The more-energetic propellant systems, using fluorine or FLOX, demand more-effective abla- tive

Amphiphilic Polycarbonates from Carborane-Installed Cyclic Carbonates as Potential Agents for Boron Neutron Capture Therapy.

PubMed

Xiong, Hejian; Wei, Xing; Zhou, Dongfang; Qi, Yanxin; Xie, Zhigang; Chen, Xuesi; Jing, Xiabin; Huang, Yubin

2016-09-21

Carboranes with rich boron content have showed significant applications in the field of boron neutron capture therapy. Biodegradable derivatives of carborane-conjugated polymers with well-defined structure and tunable loading of boron atoms are far less explored. Herein, a new family of amphiphilic carborane-conjugated polycarbonates was synthesized by ring-opening polymerization of a carborane-installed cyclic carbonate monomer. Catalyzed by TBD from a poly(ethylene glycol) macroinitiator, the polymerization proceeded to relatively high conversions (>65%), with low polydispersity in a certain range of molecular weight. The boron content was readily tuned by the feed ratio of the monomer and initiator. The resultant amphiphilic polycarbonates self-assembled in water into spherical nanoparticles of different sizes depending on the hydrophilic-to-hydrophobic ratio. It was demonstrated that larger nanoparticles (PN150) were more easily subjected to protein adsorption and captured by the liver, and smaller nanoparticles (PN50) were more likely to enter cancer cells and accumulate at the tumor site. PN50 with thermal neutron irradiation exhibited the highest therapeutic efficacy in vivo. The new synthetic method utilizing amphiphilic biodegradable boron-enriched polymers is useful for developing more-selective and -effective boron delivery systems for BNCT.

Effects of boron and selenium on mallard reproduction and duckling growth and survival

USGS Publications Warehouse

Stanley, T.R.; Smith, G.J.; Hoffman, D.J.; Heinz, G.H.; Rosscoe, R.

1996-01-01

Boron (B) and selenium (Se) sometimes occur together in high concentrations in the environment and can accumulate in plants and invertebrates consumed by waterfowl. One hundred twenty-six pairs of breeding mallards (Anas platyrhynchos) were fed diets supplemented with B (as boric acid) at 0, 450, or 900 ppm, in combination with Se (as seleno-DL-methionine) at 0, 3.5, or 7 ppm, in a replicated factorial experiment. Ducklings produced received the same treatment combination as their parents. Boron and Se accumulated in adult liver, egg, and duckling liver. In adults, B and Se caused weight loss, and B decreased hemoglobin concentration, egg weight, and egg fertility. Both B and Se reduced hatching success and duckling weight, and B reduced duckling growth and duckling production, and caused several alterations in duckling liver biochemistry. Duckling survival was not reduced by B or Se, and neither B nor Se had histopathologic effects on adult or duckling liver, kidney, or spleen. There was little evidence of interaction between B and Se. This study demonstrated that B and Se, in the chemical forms and at the dietary levels administered in this study, can adversely affect mallard reproduction and duckling growth.

Effects of Boron foliar-fertilization on irrigated soybean (Glycine max L. Merr.) in the Mississippi River Valley Delta of the midsouth, USA

USDA-ARS?s Scientific Manuscript database

Irrigated soybeans in the Mississippi Delta have been reported to with increased seed yields when fertilized with a boron (B). Furrow irrigated soybean cultivars were foliar fertilized with a B solution at growth stages R3 and/or R5. No consistent trends in yield or seed weight were noted. No phy...

Boron carbide nanostructures: A prospective material as an additive in concrete

NASA Astrophysics Data System (ADS)

Singh, Paviter; Kaur, Gurpreet; Kumar, Rohit; Kumar, Umesh; Singh, Kulwinder; Kumar, Manjeet; Bala, Rajni; Meena, Ramovatar; Kumar, Akshay

2018-05-01

In recent decades, manufacture and ingestion of concrete have increased particularly in developing countries. Due to its low cost, safety and strength, concrete have become an economical choice for protection of radiation shielding material in nuclear reactors. As boron carbide has been known as a neutron absorber material makes it a great candidate as an additive in concrete for shielding radiation. This paper presents the synthesis of boron carbide nanostructures by using ball milling method. The X-ray diffraction pattern, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope analysis confirms the formation of boron carbide nanostructures. The effect of boron carbide nanostructures on the strength of concrete samples was demonstrated. The compressive strength tests of concrete cube B4C powder additives for 0 % and 5 % of total weight of cement was compared for different curing time period such as 7, 14, 21 and 28 days. The high compressive strength was observed when 5 wt % boron carbide nanostructures were used as an additive in concrete samples after 28 days curing time and showed significant improvement in strength.

Thermal coatings for titanium-aluminum alloys

NASA Technical Reports Server (NTRS)

Cunnington, George R.; Clark, Ronald K.; Robinson, John C.

1993-01-01

Titanium aluminides and titanium alloys are candidate materials for use in hot structure and heat-shield components of hypersonic vehicles because of their good strength-to-weight characteristics at elevated temperature. However, in order to utilize their maximum temperature capability, they must be coated to resist oxidation and to have a high total remittance. Also, surface catalysis for recombination of dissociated species in the aerodynamic boundary layer must be minimized. Very thin chemical vapor deposition (CVD) coatings are attractive candidates for this application because of durability and very light weight. To demonstrate this concept, coatings of boron-silicon and aluminum-boron-silicon compositions were applied to the titanium-aluminides alpha2 (Ti-14Al-21Nb), super-alpha2 (Ti-14Al-23-Nb-2V), and gamma (Ti-33Al-6Nb-1Ta) and to the titanium alloy beta-21S (Ti-15Mo-3Al-3Nb-0.2Si). Coated specimens of each alloy were subjected to a set of simulated hypersonic vehicle environmental tests to determine their properties of oxidation resistance, surface catalysis, radiative emittance, and thermal shock resistance. Surface catalysis results should be viewed as relative performance only of the several coating-alloy combinations tested under the specific environmental conditions of the LaRC Hypersonic Materials Environmental Test System (HYMETS) arc-plasma-heated hypersonic wind tunnel. Tests were also conducted to evaluate the hydrogen transport properties of the coatings and any effects of the coating processing itself on fatigue life of the base alloys. Results are presented for three types of coatings, which are as follows: (1) a single layer boron silicon coating, (2) a single layer aluminum-boron-silicon coating, and (3) a multilayer coating consisting of an aluminum-boron-silicon sublayer with a boron-silicon outer layer.

Ductile tungsten-nickel-alloy and method for manufacturing same

DOEpatents

Ludwig, Robert L.

1978-01-01

The tensile elongation of a tungsten-nickel-iron alloy containing essentially 95 weight percent reprocessed tungsten, 3.5 weight percent nickel, and 1.5 weight percent iron is increased from a value of less than about 1 percent up to about 23 percent by the addition of less than 0.5 weight percent of a reactive metal consisting of niobium and zirconium.

Nickel aluminide alloy for high temperature structural use

DOEpatents

Liu, Chain T.; Sikka, Vinod K.

1991-01-01

The specification discloses nickel aluminide alloys including nickel, aluminum, chromium, zirconium and boron wherein the concentration of zirconium is maintained in the range of from about 0.05 to about 0.35 atomic percent to improve the ductility, strength and fabricability of the alloys at 1200.degree. C. Titanium may be added in an amount equal to about 0.2 to about 0.5 atomic percent to improve the mechanical properties of the alloys and the addition of a small amount of carbon further improves hot fabricability.

Mechanical properties of particulate composites based on a body-centered-cubic Mg-Li alloy containing boron

NASA Technical Reports Server (NTRS)

Whalen, R. T.; Gonzalez-Doncel, G.; Robinson, S. L.; Sherby, O. D.

1989-01-01

The effect of substituting the Mg metal in Mg-B composites by a Mg-14 wt pct Li solid solution on the ductility of the resulting composite was investigated using elastic modulus measurements on the P/M composite material prepared with a dispersion of B particles (in a vol pct range of 0-30) in a matrix of Mg-14 wt pct Li-1.5 wt pct Al. It was found that the elastic modulus of the composites increased rapidly with increasing boron, with specific stiffness values reaching about two times that of most structural materials. The values of the compression and tensile strengths increased significantly with boron additions. Good tensile ductility was achieved at the level of 10 vol pct B. However, at 20 vol pct B, the Mg-Li composite exhibited only limited tensile ductility (about 2 percent total elongation).

Fast-spectrum space-power-reactor concepts using boron control devices

NASA Technical Reports Server (NTRS)

Mayo, W.

1973-01-01

Several fast-spectrum space power reactor concepts that use boron carbide control devices were examined to determine the neutronic feasibility of the designs. The designs considered were (1) a 199-fuel-pin, 12-poison-reflector-control-drum reactor; (2) a 232-fuel-pin reactor with 12 reflector drums and three in-core control rods; (3) a 337-fuel-pin design with 12 incore control rods; and a 181-fuel-pin design with six drums closely coupled to the core to increase reactivity per drum. Adequate reactivity control and excess reactivity could be obtained for each concept, and the goals of 50,000 hours at 2.17 thermal megawatts with a lithium-7 coolant outlet temperature of 1222 K could be met without exceeding the 1-percent-clad-creep criterion. Heating rates in the boron carbide were calculated, but a heat transfer analysis was not done.

Analysis of a boron-carbide-drum-controlled critical reactor experiment

NASA Technical Reports Server (NTRS)

Mayo, W. T.

1972-01-01

In order to validate methods and cross sections used in the neutronic design of compact fast-spectrum reactors for generating electric power in space, an analysis of a boron-carbide-drum-controlled critical reactor was made. For this reactor the transport analysis gave generally satisfactory results. The calculated multiplication factor for the most detailed calculation was only 0.7-percent Delta k too high. Calculated reactivity worth of the control drums was $11.61 compared to measurements of $11.58 by the inverse kinetics methods and $11.98 by the inverse counting method. Calculated radial and axial power distributions were in good agreement with experiment.

12 CFR 3.52 - Simple risk-weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... this paragraph (b). (1) Zero percent risk weight equity exposures. An equity exposure to a sovereign... International Monetary Fund, an MDB, and any other entity whose credit exposures receive a zero percent risk weight under § 3.32 may be assigned a zero percent risk weight. (2) 20 percent risk weight equity...

Boron-Based Hydrogen Storage: Ternary Borides and Beyond

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

Vajo, John J.

DOE continues to seek reversible solid-state hydrogen materials with hydrogen densities of ≥11 wt% and ≥80 g/L that can deliver hydrogen and be recharged at moderate temperatures (≤100 °C) and pressures (≤100 bar) enabling incorporation into hydrogen storage systems suitable for transportation applications. Boron-based hydrogen storage materials have the potential to meet the density requirements given boron’s low atomic weight, high chemical valance, and versatile chemistry. However, the rates of hydrogen exchange in boron-based compounds are thus far much too slow for practical applications. Although contributing to the high hydrogen densities, the high valance of boron also leads to slowmore » rates of hydrogen exchange due to extensive boron-boron atom rearrangements during hydrogen cycling. This rearrangement often leads to multiple solid phases occurring over hydrogen release and recharge cycles. These phases must nucleate and react with each other across solid-solid phase boundaries leading to energy barriers that slow the rates of hydrogen exchange. This project sought to overcome the slow rates of hydrogen exchange in boron-based hydrogen storage materials by minimizing the number of solid phases and the boron atom rearrangement over a hydrogen release and recharge cycle. Two novel approaches were explored: 1) developing matched pairs of ternary borides and mixed-metal borohydrides that could exchange hydrogen with only one hydrogenated phase (the mixed-metal borohydride) and only one dehydrogenated phase (the ternary boride); and 2) developing boranes that could release hydrogen by being lithiated using lithium hydride with no boron-boron atom rearrangement.« less

Exfoliation of Hexagonal Boron Nitride via Ferric Chloride Intercalation

NASA Technical Reports Server (NTRS)

Hung, Ching-cheh; Hurst, Janet; Santiago, Diana; Rogers, Richard B.

2014-01-01

Sodium fluoride (NaF) was used as an activation agent to successfully intercalate ferric chloride (FeCl3) into hexagonal boron nitride (hBN). This reaction caused the hBN mass to increase by approx.100 percent, the lattice parameter c to decrease from 6.6585 to between 6.6565 and 6.6569 ?, the x-ray diffraction (XRD) (002) peak to widen from 0.01deg to 0.05deg of the full width half maximum value, the Fourier transform infrared (FTIR) spectrum's broad band (1277/cm peak) to change shape, and new FTIR bands to emerge at 3700 to 2700 and 1600/cm. This indicates hBN's structural and chemical properties are significantly changed. The intercalated product was hygroscopic and interacted with moisture in the air to cause further structural and chemical changes (from XRD and FTIR). During a 24-h hold at room temperature in air with 100 percent relative humidity, the mass increased another 141 percent. The intercalated product, hydrated or not, can be heated to 750 C in air to cause exfoliation. Exfoliation becomes significant after two intercalation-air heating cycles, when 20-nm nanosheets are commonly found. Structural and chemical changes indicated by XRD and FTIR data were nearly reversed after the product was placed in hydrochloric acid (HCl), resulting in purified, exfoliated, thin hBN products.

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Identity. The color additive chromium-cobalt-aluminum oxide is a blue-green pigment obtained by calcining a... percent each) of oxides of barium, boron, silicon, and nickel. (b) Specifications. Chromium-cobalt... milliliters of 0.5 N hydrochloric acid. (c) Uses and restrictions. The color additive chromium-cobalt-aluminum...

Selective boron delivery to murine tumors by lipophilic species incorporated in the membranes of unilamellar liposomes

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

Feakes, D.A.; Shelly, K.; Hawthorne, M.F.

1995-02-28

The nido-carborane species K[nido-7-CH{sub 3}(CH{sub 2}){sub 15}-7,8-C{sub 2}B{sub 9}H{sub 11}] has been synthesized for use as an addend for the bilayer membrane of liposomes. Small unilamellar vesicles, composed of distearoylphosphatidylcholine/cholesterol, 1:1, and incorporating K[nido-7-CH{sub 3}(CH{sub 2}){sub 15}-7,8-C{sub 2}B{sub 9}H{sub 11}] in the bilayer, have been investigated in vivo. The time-course biodistribution of boron delivered by these liposomes was determined by inductively coupled plasma-atomic emission spectroscopy analyses after the injection of liposomal suspensions in BALB/c mice bearing EMT6 mammary adenocarcinomas. At the low injected doses normally used ({approx}5-10 mg of boron per kg of body weight), peak tumor boron concentrations ofmore » {approx}35 {mu}g of boron per g of tissue and tumor/blood boron ratios of {approx}8 were achieved. These values are sufficiently high for the successful application of boron neutron capture therapy. The bilayer-embedded boron compound may provide the sole boron source or, alternatively, a concentrated aqueous solution of a hydrophilic boron compound may also be encapsulated within the liposomes to provide a dose enhancement. Thus, the incorporation of both K[nido-7-CH{sub 3}(CH{sub 2}){sub 15}-7,8-C{sub 2}B{sub 9}H{sub 11}] and the hydrophilic species, Na{sub 3}[1-(2{prime}-B{sub 10}H{sub 9})-2-NH{sub 3}B{sub 10}H{sub 8}], within the same liposomes demonstrated significantly enhanced biodistribution characteristics, exemplified by maximum tumor boron concentrations of {approx} 50 {mu}g of boron per g of tissue and tumor/blood boron ratios of {approx} 6. 18 refs., 1 fig.« less

Stabilization of polyaniline solutions through additives

DOEpatents

Wrobleski, D.A.; Benicewicz, B.C.

1996-12-10

A stabilized non-conductive polyaniline solution comprising from about 1 to about 10 percent by weight polyaniline or a polyaniline derivative, from about 90 to about 99 percent by weight N-methylpyrrolidone, and from about 0.5 percent by weight to about 15 percent by weight of a solution stabilizing additive selected from the group consisting of hindered amine light stabilizers, polymeric amines, and dialkylamines, percent by weight of additive based on the total weight of polyaniline or polyaniline derivative is provided together with a method for stabilizing a polyaniline solution. 4 figs.

Stabilization of polyaniline solutions through additives

DOEpatents

Wrobleski, Debra A.; Benicewicz, Brian C.

1996-01-01

A stabilized non-conductive polyaniline solution comprising from about 1 to bout 10 percent by weight polyaniline or a polyaniline derivative, from about 90 to about 99 percent by weight N-methylpyrrolidone, and from about 0.5 percent by weight to about 15 percent by weight of a solution stabilizing additive selected from the group consisting of hindered amine light stabilizers, polymeric amines, and dialkylamines, percent by weight of additive based on the total weight of polyaniline or polyaniline derivative is provided together with a method for stabilizing a polyaniline solution.

Corrosion Inhibition in High Temperature Environment

DTIC Science & Technology

1993-06-28

levels of sodium , sulfur, and vanadium. Low quality 12 marine residual fuels, for example, may contain up to 0.2 weight 13 percent ash which contains...appreciable amounts of sodium , up to 5 14 weight percent sulfur and up to 0.06 weight percent or 600 ppm 15 vanadium. Low grades of marine distillate...fuels are allowed up to 16 0.05 weight percent ash which contains appreciable amounts of 17 sodium , up to 2 weight percent sulfur and up to 100 ppm

Thermally grown oxide and diffusions for automatic processing of integrated circuits

NASA Technical Reports Server (NTRS)

Kennedy, B. W.

1979-01-01

A totally automated facility for semiconductor oxidation and diffusion was developed using a state-of-the-art diffusion furnace and high temperature grown oxides. Major innovations include: (1) a process controller specifically for semiconductor processing; (2) an automatic loading system to accept wafers from an air track, insert them into a quartz carrier and then place the carrier on a paddle for insertion into the furnace; (3) automatic unloading of the wafers back onto the air track, and (4) boron diffusion using diborane with plus or minus 5 percent uniformity. Processes demonstrated include Wet and dry oxidation for general use and for gate oxide, boron diffusion, phosphorous diffusion, and sintering.

Measurement of the time-temperature dependent dynamic mechanical properties of boron/aluminum composites

NASA Technical Reports Server (NTRS)

Dicarlo, J. A.; Maisel, J. E.

1978-01-01

A flexural vibration test and associated equipment were developed to accurately measure the low strain dynamic modulus and damping of composite materials from -200 C to over 500 C. The basic test method involves the forced vibration of composite bars at their resonant free-free flexural modes in a high vacuum cryostat furnace. The accuracy of these expressions and the flexural test was verified by dynamic moduli and damping capacity measurements on 50 fiber volume percent boron/aluminum (B/Al) composites vibrating near 2000 Hz. The phase results were summarized to permit predictions of the B/Al dynamic behavior as a function of frequency, temperature, and fiber volume fraction.

Hydrogen-based electrochemical energy storage

DOEpatents

Simpson, Lin Jay

2013-08-06

An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

DOE Research Contributions to Radiation and Cancer Therapy

Science.gov Websites

dropdown arrow Site Map A-Z Index Menu Synopsis DOE Research Contributions to Radiation and Cancer Therapy research has made many contributions to radiation and cancer therapy, including PEREGRINE and Boron Neutron planning radiation treatment for cancer patients. About 90 percent of radiation treatment patients receive

Hot isostatic pressing of silicon nitride with boron nitride, boron carbide, and carbon additions

NASA Technical Reports Server (NTRS)

Mieskowski, Diane M.; Sanders, William A.

1989-01-01

Si3N4 test bars containing additions of BN, B4C, and C, were hot isostatically pressed in Ta cladding at 1900 and 2050 C to 98.9 percent to 99.5 percent theoretical density. Room-temperature strength data on specimens containing 2 wt pct BN and 0.5 wt pct C were comparable to data obtained for Si3N4 sintered with Y2O3, Y2O3 and Al2O3, or ZrO2. The 1370 C strengths were less than those obtained for additions of Y2O3 or ZrO2 but greater than those obtained from a combination of Y2O3 and Al2O3. SEM fractography indicated that, as with other types of Si3N4, room-temperature strength was controlled by processing flaws. The decrease in strength at 1370 C was typical of Si3N4 having an amorphous grain-boundary phase. The primary advantage of nonoxide additions appears to be in facilitating specimen removal from the Ta cladding.

75 FR 6631 - Stainless Steel Sheet and Strip in Coils from Japan: Final Results of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

... and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent or less..., phosphorus of no more than 0.045 percent, sulfur of no more than 0.03 percent, lanthanum of less than 0.002... weight, 0.05 percent or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less...

Eccentric exercise training as a countermeasure to non-weight-bearing soleus muscle atrophy

NASA Technical Reports Server (NTRS)

Kirby, Christopher R.; Ryan, Mirelle J.; Booth, Frank W.

1992-01-01

This investigation tested whether eccentric resistance training could prevent soleus muscle atrophy during non-weight bearing. Adult female rats were randomly assigned to either weight bearing +/- intramuscular electrodes or non-weight bearing +/- intramuscular electrodes groups. Electrically stimulated maximal eccentric contractions were performed on anesthetized animals at 48-h intervals during the 10-day experiment. Non-weight bearing significantly reduced soleus muscle wet weight (28-31 percent) and noncollagenous protein content (30-31 percent) compared with controls. Eccentric exercise training during non-weight bearing attenuated but did not prevent the loss of soleus muscle wet weight and noncollagenous protein by 77 and 44 percent, respectively. The potential of eccentric exercise training as an effective and highly efficient counter-measure to non-weight-bearing atrophy is demonstrated in the 44 percent attenuation of soleus muscle noncollagenous protein loss by eccentric exercise during only 0.035 percent of the total non-weight-bearing time period.

12 CFR 324.152 - Simple risk weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... (that is, between zero and -1), then E equals the absolute value of RVC. If RVC is negative and less... the lowest applicable risk weight in this section. (1) Zero percent risk weight equity exposures. An....131(d)(2) is assigned a zero percent risk weight. (2) 20 percent risk weight equity exposures. An...

Measurements and simulations of boron carbide as degrader material for proton therapy.

PubMed

Gerbershagen, Alexander; Baumgarten, Christian; Kiselev, Daniela; van der Meer, Robert; Risters, Yannic; Schippers, Marco

2016-07-21

We report on test measurements using boron carbide (B4C) as degrader material in comparison with the conventional graphite, which is currently used in many proton therapy degraders. Boron carbide is a material of lower average atomic weight and higher density than graphite. Calculations predict that, compared to graphite, the use of boron carbide results in a lower emittance behind the degrader due to the shorter degrader length. Downstream of the acceptance defining collimation system we expect a higher beam transmission, especially at low beam energies. This is of great interest in proton therapy applications as it allows either a reduction of the beam intensity extracted from the cyclotron leading to lower activation or a reduction of the treatment time. This paper summarizes the results of simulations and experiments carried out at the PROSCAN facility at the Paul Scherrer Institute(1). The simulations predict an increase in the transmitted beam current after the collimation system of approx. 30.5% for beam degradation from 250 to 84 MeV for a boron carbide degrader compared to graphite. The experiment carried out with a boron carbide block reducing the energy to 84 MeV yielded a transmission improvement of 37% compared with the graphite degrader set to that energy.

Effects of boron derivatives on extracellular matrix formation.

PubMed

Benderdour, M; Van Bui, T; Hess, K; Dicko, A; Belleville, F; Dousset, B

2000-10-01

Boric acid solution (3%) dramatically improves wound healing through action on the extracellular matrix, a finding that has been obtained in vitro. Consequently, investigations are presently underway to produce boronated compounds having a therapeutical effectiveness similar to that of boric acid. On the basis of experimental results obtained with boric acid, we examined the effects of boron derivatives on extracellular matrix formation and degradation and analyzed their potential toxicity by using two biological models (chick embryo cartilage and human fibroblasts). The four boron derivatives tested in this study (triethanolamine borate; N-diethyl-phosphoramidate-propylboronique acid; 2,2 dimethylhexyl-1,3-propanediol-aminopropylboronate and 1,2 propanediol-aminopropylboronate) mimicked the effects of boric acid. They induced a decrease of intracellular concentrations in extracellular matrix macromolecules (proteoglycans, proteins)-associated with an increase of their release in culture medium and stimulated the activity of intra- and extracellular proteases. Similarly to boric acid, these actions occurred after exposure of the cells to concentrations of all boron derivatives without apparent toxic effects. The compounds were found to be more toxic than boric acid itself when concentrations were calculated according to their molecular weight. Nevertheless, these in vitro preliminary results demonstrate effects of boron derivatives that may be of therapeutic benefit in wound repair.

Fabrication Of Carbon-Boron Reinforced Dry Polymer Matrix Composite Tape

NASA Technical Reports Server (NTRS)

Belvin, Harry L.; Cano, Roberto J.; Treasure, Monte; Shahood, Thomas W.

1999-01-01

Future generation aerospace vehicles will require specialized hybrid material forms for component structure fabrication. For this reason, high temperature composite prepregs in both dry and wet forms are being developed at NASA Langley Research Center (LaRC). In an attempt to improve compressive properties of carbon fiber reinforced composites, a hybrid carbon-boron tape was developed and used to fabricate composite laminates which were subsequently cut into flexural and compression specimens and tested. The hybrid material, given the designation HYCARB, was fabricated by modifying a previously developed process for the manufacture of dry polymer matrix composite (PMC) tape at LaRC. In this work, boron fibers were processed with IM7/LaRC(TradeMark)IAX poly(amide acid) solution-coated prepreg to form a dry hybrid tape for Automated Tow Placement (ATP). Boron fibers were encapsulated between two (2) layers of reduced volatile, low fiber areal weight poly(amide acid) solution-coated prepreg. The hybrid prepreg was then fully imidized and consolidated into a dry tape suitable for ATP. The fabrication of a hybrid boron material form for tow placement aids in the reduction of the overall manufacturing cost of boron reinforced composites, while realizing the improved compression strengths. Composite specimens were press-molded from the hybrid material and exhibited excellent mechanical properties.

Ineffectiveness of commercial weight-loss programs for achieving modest but meaningful weight loss: Systematic review and meta-analysis.

PubMed

McEvedy, Samantha M; Sullivan-Mort, Gillian; McLean, Siân A; Pascoe, Michaela C; Paxton, Susan J

2017-10-01

This study collates existing evidence regarding weight loss among overweight but otherwise healthy adults who use commercial weight-loss programs. Systematic search of 3 databases identified 11 randomized controlled trials and 14 observational studies of commercial meal-replacement, calorie-counting, or pre-packaged meal programs which met inclusion criteria. In meta-analysis using intention-to-treat data, 57 percent of individuals who commenced a commercial weight program lost less than 5 percent of their initial body weight. One in two (49%) studies reported attrition ≥30 percent. A second meta-analysis found that 37 percent of program completers lost less than 5 percent of initial body weight. We conclude that commercial weight-loss programs frequently fail to produce modest but clinically meaningful weight loss with high rates of attrition suggesting that many consumers find dietary changes required by these programs unsustainable.

12 CFR 3.152 - Simple risk weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... applicable risk weight in this section. (1) Zero percent risk weight equity exposures. An equity exposure to... assigned a zero percent risk weight. (2) 20 percent risk weight equity exposures. An equity exposure to a... equals zero. If RVC is negative and greater than or equal to -1 (that is, between zero and -1), then E...

27 CFR 21.105 - Citronella oil, natural.

Code of Federal Regulations, 2010 CFR

2010-04-01

... percent by weight. (2) Aldehyde content (as Citronellal). Not less than 30 percent by weight. (3...) Aldehyde content (as Citronellal). Not less than 7 percent by weight. (3) Refractive index at 20 °C. 1.4790...

27 CFR 21.105 - Citronella oil, natural.

Code of Federal Regulations, 2013 CFR

2013-04-01

... percent by weight. (2) Aldehyde content (as Citronellal). Not less than 30 percent by weight. (3...) Aldehyde content (as Citronellal). Not less than 7 percent by weight. (3) Refractive index at 20 °C. 1.4790...

27 CFR 21.105 - Citronella oil, natural.

Code of Federal Regulations, 2012 CFR

2012-04-01

... percent by weight. (2) Aldehyde content (as Citronellal). Not less than 30 percent by weight. (3...) Aldehyde content (as Citronellal). Not less than 7 percent by weight. (3) Refractive index at 20 °C. 1.4790...

27 CFR 21.105 - Citronella oil, natural.

Code of Federal Regulations, 2014 CFR

2014-04-01

... percent by weight. (2) Aldehyde content (as Citronellal). Not less than 30 percent by weight. (3...) Aldehyde content (as Citronellal). Not less than 7 percent by weight. (3) Refractive index at 20 °C. 1.4790...

27 CFR 21.105 - Citronella oil, natural.

Code of Federal Regulations, 2011 CFR

2011-04-01

... percent by weight. (2) Aldehyde content (as Citronellal). Not less than 30 percent by weight. (3...) Aldehyde content (as Citronellal). Not less than 7 percent by weight. (3) Refractive index at 20 °C. 1.4790...

Assessment of the visibility impairment caused by the emissions from the proposed power plant at Boron, California

NASA Technical Reports Server (NTRS)

Bergstrom, R. W.; Doyle, J. R.; Johnson, C. D.; Holman, H. Y.; Wojcik, M. A.

1980-01-01

The current atmospheric conditions and visibility were modeled, and the effect of the power plant effluent was then added to determine its influence upon the prevailing visibility; the actual reduction in visibility being a function of meteorological conditions and observer-plume-target geometry. In the cases investigated, the perceptibility of a target was reduced by a minimum of 10 percent and a maximum of 100 percent. This significant visual impact would occur 40 days per year in the Edwards area with meteorological conditions such as to cause some visual impact 80 days per year.

Glass-ceramic composition for hermetic seals

DOEpatents

Ballard, Jr., Clifford P.

1979-01-01

The invention relates to a glass-ceramic composition having a high fracture strength adaptable for hermetically sealing to chromium bearing iron or nickel base alloys at temperatures of between about 950.degree. C to about 1100.degree. C to form a hermetically sealed insulator body, comprising from about 55 to about 65 weight percent SiO.sub.2, from about 0 to about 5 weight percent Al.sub.2 O.sub.3, from about 6 to about 11 weight % Li.sub.2 O, from about 25 to about 32 weight percent BaO, from about 0.5 to about 1.0 weight percent CoO and from about 1.5 to about 3.5 weight percent P.sub.2 O.sub.5.

Water-soluble factors eluated from surface pre-reacted glass-ionomer filler promote osteoblastic differentiation of human mesenchymal stem cells

PubMed Central

Nemoto, Akira; Chosa, Naoyuki; Kyakumoto, Seiko; Yokota, Seiji; Kamo, Masaharu; Noda, Mamoru; Ishisaki, Akira

2018-01-01

Surface pre-reacted glass-ionomer (S-PRG)-containing dental materials, including composite and coating resins have been used for the restoration and/or prevention of dental cavities. S-PRG is known to have the ability to release aluminum, boron, fluorine, silicon, and strontium ions. Aluminum ions are known to be inhibitors whereas boron, fluorine, silicon, and strontium ions are known to be promoters of mineralization, via osteoblasts. However, it remains to be clarified how an aqueous eluate obtained from S-PRG containing these ions affects the ability of mesenchymal stem cells (MSCs), which are known to be present in dental pulp and bone marrow, to differentiate into osteogenic cell types. The present study demonstrated that 200- to 1,000-fold-diluted aqueous eluates obtained from S-PRG significantly upregulated the mRNA expression level of the osteogenic differentiation marker alkaline phosphatase in human MSCs (hMSCs) without exhibiting the cytotoxic effect. In addition, the 500- to 1,000-fold-diluted aqueous eluates obtained from S-PRG significantly and clearly promoted mineralization of the extracellular matrix of hMSCs. It was additionally demonstrated that hMSCs cultured on the cured resin composites containing S-PRG fillers exhibited osteogenic differentiation in direct correlation with the weight percent of S-PRG fillers. These results strongly suggested that aqueous eluates of S-PRG fillers promoted hard tissue formation by hMSCs, implicating that resins containing S-PRG may act as a useful biomaterial to cover accidental exposure of dental pulp. PMID:29257332

75 FR 62101 - Stainless Steel Sheet and Strip in Coils From the Republic of Korea: Final Results of Expedited...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-07

... and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent or less..., phosphorus of no more than 0.045 percent, sulfur of no more than 0.03 percent, lanthanum of less than 0.002... comprise, by weight, 0.05 percent or less, with phosphorus and sulfur each comprising, by weight, 0.03...

Dry Process for Making Polyimide/ Carbon-and-Boron-Fiber Tape

NASA Technical Reports Server (NTRS)

Belvin, Harry L.; Cano, Roberto J.; Johnston, Norman J.; Marchello, Joseph M.

2003-01-01

A dry process has been invented as an improved means of manufacturing composite prepreg tapes that consist of high-temperature thermoplastic polyimide resin matrices reinforced with carbon and boron fibers. Such tapes are used (especially in the aircraft industry) to fabricate strong, lightweight composite-material structural components. The inclusion of boron fibers results in compression strengths greater than can be achieved by use of carbon fibers alone. The present dry process is intended to enable the manufacture of prepreg tapes (1) that contain little or no solvent; (2) that have the desired dimensions, fiber areal weight, and resin content; and (3) in which all of the fibers are adequately wetted by resin and the boron fibers are fully encapsulated and evenly dispersed. Prepreg tapes must have these properties to be useable in the manufacture of high-quality composites by automated tape placement. The elimination of solvent and the use of automated tape placement would reduce the overall costs of manufacturing.

Trace metals in corals--hind casting environmental chemical changes in the tropical Atlantic waters

NASA Astrophysics Data System (ADS)

Holmes, C. W.; Koenig, A.; Ridley, W. I.; Wilson, S. A.

2002-12-01

As corals grow, they secrete a calcareous skeleton with the aid of photosynthetic activity of endosymbiotic dinoflagellates (zooxanthellae). The rate of this secretion varies inter-annually. Entrapped with the carbonate are trace substances that record the chemistry of the surrounding ocean. Detailing changes in chemistry requires careful and very tedious high-resolution sampling. The advent of laser ablation inductive couple plasma/mass spectroscopy (LA-ICP/MS) circumvents this sampling problem. This method also permits a continuous scan of the entire coral skeleton. Another problem has been the lack of a carbonate standard which appears to be resolved with the creation of an artificial carbonate standard (USGS MAC-1). This standard is presently undergoing rigorous analysis, but preliminary results are very positive. The LA-ICP/MS data of three Atlantic corals reveals an intriguing distribution of trace metals and boron that may be related to climatic driven chemical changes during the last hundred years. The distribution of the trace metals appears to have an association with three climate signals: 1. the strength of the North Atlantic Oscillation (NAO), 2. the local effects of El Nino in the Florida region and 3. change in oceanic chemistry, possibly due to rising CO2. Aluminum and titanium levels vary with the strength of the NAO. The highest concentrations occur at the time of strong positive NOA when there is large amount of sediment transported off the deserts of North Africa. This relationship is particularly strong in the coral from the Cape Verde Islands. Along the eastern seaboard of the Atlantic, the relationship is not as pronounced but still observable. Nutrients and anthropogenic trace metals, such as zinc, lead, and mercury appear to correlate with local conditions and show a weak correspondence to the El Nino as it affects south Florida. Boron variation is directly related to the high-density bands of the corals. The long-term record of boron concentrations in a coral collected at Looe Key shows an increase of approximately 25 percent from 1885 to a peak in the early 1970s. From the peak until 1983, the time of collection, boron decreases about 15 percent. Boron in the twenty-year record in the Cape Verde coral shows a similar decrease. Hemming and others (1986) found that the boron concentration and the heavy isotope of carbon, 13C are concentrated in the annual high-density bands. They proposed that this phenomenon is the result of the physiological processes leading to the precipitation of the carbonate structure. Assuming that the zooanthellae are driving the photosynthetic processes, the explanation of high boron and associated high δ13C is the result of increased primary productivity. As a result, 12C is preferentially utilized within the cell leaving the extracelluar fluids in the region between the basal ectoderm and exoskeleton enriched in 13C. In addition, this increased activity increases HCO3^{-} leading to the higher pH in these fluids. This increase in pH, favors an increase in the reactive species, B(OH)_{4}$-which leads to increased boron precipitation within the carbonate structure. If this model is correct, our data suggest that increases in boron reflect increases in photosynthesis from the 1800s till about 1970, then have slightly decreased.

Status and understanding of groundwater quality in the Klamath Mountains study unit, 2010: California GAMA Priority Basin Project

USGS Publications Warehouse

Bennett, George L.; Fram, Miranda S.; Belitz, Kenneth

2014-01-01

Groundwater quality in the Klamath Mountains (KLAM) study unit was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in Del Norte, Humboldt, Shasta, Siskiyou, Tehama, and Trinity Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA Priority Basin Project was designed to provide a spatially unbiased, statistically robust assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality data and explanatory factors for groundwater samples collected in 2010 by the USGS from 39 sites and on water-quality data from the California Department of Public Health (CDPH) water-quality database. The primary aquifer system was defined by the depth intervals of the wells listed in the CDPH water-quality database for the KLAM study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study included two types of assessments: (1) a status assessment, which characterized the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds, pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements, and (2) an understanding assessment, which evaluated the natural and human factors potentially affecting the groundwater quality. The assessments were intended to characterize the quality of groundwater resources in the primary aquifer system of the KLAM study unit, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by the health- or aesthetic-based benchmark concentrations) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than (>) 1.0 indicates a concentration greater than a benchmark, and a relative-concentration less than or equal to (≤) 1.0 indicates a concentration less than or equal to a benchmark. Relative-concentrations of organic constituents were classified as “high” (relative-concentration > 1.0), “moderate” (0.1 Aquifer-scale proportion was used in the status assessment as the primary metric for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentages of the primary aquifer system with moderate and low relative-concentrations, respectively. The KLAM study unit includes more than 8,800 square miles (mi2), but only those areas near the sampling sites, about 920 mi2, are included in the areal assessment of the study unit. Two statistical approaches—grid-based and spatially weighted—were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. To confirm this methodology, 90 percent confidence intervals were calculated for the grid-based high aquifer-scale proportions and were compared to the spatially weighted results, which were found to be within these confidence intervals in all cases. Grid-based results were selected for use in the status assessment unless, as was observed in a few cases, a grid-based result was zero and the spatially weighted result was not zero, in which case, the spatially weighted result was used. The status assessment showed that inorganic constituents with human-health benchmarks were detected at high relative-concentrations in 2.6 percent of the primary aquifer system and at moderate relative-concentrations in 10 percent of the system. The high aquifer-scale proportion for inorganic constituents mainly reflected the high aquifer-scale proportions of boron. Inorganic constituents with secondary maximum contaminant levels were detected at high relative-concentrations in 13 percent of the primary aquifer system and at moderate relative-concentrations in 10 percent of the system. The constituents present at high relative-concentrations included iron and manganese. Organic constituents with human-health benchmarks were not detected at high relative-concentrations, but were detected at moderate relative-concentrations in 1.9 percent of the primary aquifer system. The 1.9 percent reflected a spatially weighted moderate aquifer-scale proportion for the gasoline additive methyl tert-butyl ether. Of the 148 organic constituents analyzed, 14 constituents were detected. Only one organic constituent had a detection frequency of greater than 10 percent—the trihalomethane, chloroform. The second component of this study, the understanding assessment, identified the natural and human factors that may have affected the groundwater quality in the KLAM study unit by evaluating statistical correlations between water-quality constituents and potential explanatory factors. The potential explanatory factors evaluated were aquifer lithology, land use, hydrologic conditions, depth, groundwater age, and geochemical conditions. Results of the statistical evaluations were used to explain the occurrence and distribution of constituents in the KLAM study unit. Groundwater age distribution (modern, mixed, or pre-modern), redox class (oxic, mixed, or anoxic), and dissolved oxygen concentration were the explanatory factors that best explained occurrence patterns of the inorganic constituents. High concentrations of boron were found to be associated with groundwater classified as mixed or pre-modern with respect to groundwater age. Boron was also negatively correlated to dissolved oxygen and positively correlated to specific conductance. Iron and manganese concentrations were strongly associated with low dissolved oxygen concentrations, anoxic and mixed redox classifications, and pre-modern groundwater. Specific conductance concentrations were found to be related to pre-modern groundwater, low dissolved oxygen concentrations, and high pH. Chloroform was selected for additional evaluation in the understanding assessment because it was detected in more than 10 percent of wells sampled in the KLAM study unit. Septic tank density was the only explanatory factor that was found to relate to chloroform concentrations.

Evaluation of Ground-Water and Boron Sources by Use of Boron Stable-Isotope Ratios, Tritium, and Selected Water-Chemistry Constituents near Beverly Shores, Northwestern Indiana, 2004

USGS Publications Warehouse

Buszka, Paul M.; Fitzpatrick, John A.; Watson, Lee R.; Kay, Robert T.

2007-01-01

Concentrations of boron greater than the U.S. Environmental Protection Agency (USEPA) 900 ?g/L removal action level (RAL) standard were detected in water sampled by the USEPA in 2004 from three domestic wells near Beverly Shores, Indiana. The RAL regulates only human-affected concentrations of a constituent. A lack of well logs and screened depth information precluded identification of whether water from sampled wells, and their boron sources, were from human-affected or natural sources in the surficial aquifer, or associated with a previously defined natural, confined aquifer source of boron from the subtill or basal sand aquifers. A geochemically-based classification of the source of boron in ground water could potentially determine the similarity of boron to known sources or mixtures between known sources, or classify whether the relative age of the ground water predated the potential sources of contamination. The U.S. Geological Survey (USGS), in cooperation with the USEPA, investigated the use of a geochemical method that applied boron stable isotopes, and concentrations of boron, tritium, and other constituents to distinguish between natural and human-affected sources of boron in ground water and thereby determine if the RAL was applicable to the situation. Boron stable-isotope ratios and concentrations of boron in 17 ground-water samples and tritium concentrations in 9 ground-water samples collected in 2004 were used to identify geochemical differences between potential sources of boron in ground water near Beverly Shores, Indiana. Boron and d11B analyses for this investigation were made on unacidified samples to assure consistency of the result with unacidified analyses of d11B values from other investigations. Potential sources of boron included surficial-aquifer water affected by coal-combustion products (CCP) or domestic-wastewater, upward discharge of ground water from confined aquifers, and unaffected water from the surficial aquifer that was distant from human-affected boron sources. Boron concentrations in potential ground-water sources of boron were largest (15,700 to 24,400 ?g/L) in samples of CCP-affected surficial aquifer water from four wells at a CCP landfill and smallest (27 to 63 ?g/L) in three wells in the surficial aquifer that were distant from human-affected boron sources. Boron concentrations in water from the basal sand aquifer ranged from 656 ?g/L to 1,800 ?g/L. Boron concentrations in water from three domestic-wastewater-affected surficial aquifer wells ranged from 84 to 387 ?g/L. Among the representative ground-water samples, boron concentrations from all four samples of CCP-affected surficial aquifer water and four of five samples of water from the basal sand aquifer had concentrations greater than the RAL. A comparison of boron concentrations in acid-preserved and unacidified samples indicated that boron concentrations reported for this investigation may be from about 11 to 16 percent less than would be reported in a standard analysis of an acidified sample. The stable isotope boron-11 was most enriched in comparison to boron-10 in ground water from a confined aquifer, the basal sand aquifer (d11B, 24.6 to 34.0 per mil, five samples); it was most depleted in CCP-affected water from the surficial aquifer (d11B, 0.1 to 6.6 per mil, four samples). Domestic-wastewater-affected water from the surficial aquifer (d11B, 8.7 to 11.7 per mil, four samples) was enriched in boron-11, in comparison to individual samples of a borax detergent additive and a detergent with perborate bleach; it was intermediate in composition between basal sand aquifer water and CCP-affected water from the surficial aquifer. The similarity between a ground-water sample from the surficial aquifer and a hypothetical mixture of unaffected surficial aquifer and basal sand aquifer waters indicates the potential for long-term upward discharge of ground water into the surficial aquifer from one or more confined aquifers. Est

Extinguishing agent for combustible metal fires

DOEpatents

Riley, John F.; Stauffer, Edgar Eugene

1976-10-12

A low chloride extinguishing agent for combustible metal fires comprising from substantially 75 to substantially 94 weight percent of sodium carbonate as the basic fire extinguishing material, from substantially 1 to substantially 5 weight percent of a water-repellent agent such as a metal stearate, from substantially 2 to substantially 10 weight percent of a flow promoting agent such as attapulgus clay, and from substantially 3 to substantially 15 weight percent of a polyamide resin as a crusting agent.

Fabrication and tribological response of aluminium 6061 hybrid composite reinforced with bamboo char and boron carbide micro-fillers

NASA Astrophysics Data System (ADS)

Chethan, K. N.; Pai, Anand; Keni, Laxmikant G.; Singhal, Ashish; Sinha, Shubham

2018-02-01

Metal matrix composites (MMCs) have a wide scope of industrial applications and triumph over conventional materials due to their light weight, higher specific strength, good wear resistance and lower coefficient of thermal expansion. The present study aims at establishing the feasibility of using Bamboo charcoal particulate and boron carbide as reinforcements in Al-6061 alloy matrix and to investigate their effect on the wear of composites taking into consideration the interfacial adhesion of the reinforcements in the alloy. Al-6061 alloy was chosen as a base metallic alloy matrix. Sun-dried bamboo canes were used for charcoal preparation with the aid of a muffle furnace. The carbon content in the charcoal samples was determined by EDS (energy dispersive spectroscopy). In present study, stir casting technique was used to prepare the samples with 1%, 2%, and 3% weight of bamboo charcoal and boron carbide with Al-6061. The fabricated composites were homogenised at 570°C for 6 hours and cooled at room temperature. Wear studies were carried out on the specimens with different speed and loads. It was found that wear rate and coefficient of friction decreased with increase in the reinforcement content.

Spatial and temporal distribution of specific conductance, boron, and phosphorus in a sewage-contaminated aquifer near Ashumet Pond, Cape Cod, Massachusetts

USGS Publications Warehouse

Bussey, K.W.; Walter, D.A.

1996-01-01

Spatial and temporal distributions of specific conductance, boron, and phosphorus were determined in a sewage-contaminated sand and gravel aquifer near Ashumet Pond, Cape Cod, Massachusetts. The source of contamination is secondarily treated sewage that has been discharged onto rapid- infiltration sand beds at the Massachusetts Military Reservation since 1936. Contaminated ground water containing as much as 2 milligrams per liter of dissolved phosphorus is discharging into Ashumet Pond, and there is concern that the continued discharge of phosphorus into the pond will accelerate eutrophication of the pond. Water-quality data collected from observation wells and multilevel samplers from June through July 1995 were used to delineate the spatial distributions of specific conductance, boron, and phosphorus. Temporal distributions were determined using sample-interval-weighted average concen- trations calculated from data collected in 1993, 1994, and 1995. Specific conductances were greater than 400 microsiemens per centimeter at 25C as far as 1,200 feet downgradient from the infiltration beds. Boron concentrations were greater than 400 micrograms per liter as far as 1,800 feet down- gradient from the beds and phosphorus concen- trations were greater than 3.0 milligrams per liter as far as 1,200 feet from the beds. Variability in distributions of specific conductance and boron concentrations is attributed to the history and distribution of sewage disposal onto the infiltration beds. The distribution of phosphorus concentrations also is related to the history and distribution of sewage disposal onto the beds but additional variability is caused by chemical interactions with the aquifer materials. Temporal changes in specific conductance and boron from 1993 to 1995 were negligible, except in the lower part of the plume (below an altitude of about 5 feet above sea level), where changes in weighted-average specific conductance were greater than 100 microsiemens per centimeter at 25C. Temporal changes in phosphorus generally were small except in the lower part of the plume, where weighted-average phosphorus concentrations decreased more than 1.3 milligrams per liter from 1993 to 1994. This decrease was accompanied by an increase in specific conductance. High concen- trations of phosphorus associated with low and moderate specific conductances possibly are the result of rapid phosphorus desorption in response to an influx of uncontaminated ground water. As a result of the cessation of sewage disposal in December 1995, clean, oxygenated water moving into contaminated parts of the aquifer may cause rapid desorption of sorbed phosphorus and temporarily result in high dissolved phosphorus concentrations in the aquifer.

Silica nanoparticles carrying boron-containing polymer brushes

NASA Astrophysics Data System (ADS)

Brozek, Eric M.; Mollard, Alexis H.; Zharov, Ilya

2014-05-01

A new class of surface-modified silica nanoparticles has been developed for potential applications in boron neutron capture therapy. Sub-50 nm silica particles were synthesized using a modified Stöber method and used in surface-initiated atom transfer radical polymerization of two biocompatible polymers, poly(2-(hydroxyethyl)methacrylate) and poly(2-(methacryloyloxy)ethyl succinate). The carboxylic acid and hydroxyl functionalities of the polymeric side chains were functionalized with carboranyl clusters in high yields. The resulting particles were characterized using DLS, TEM, solution 1H NMR, solid state 11B NMR and thermogravimetric analysis. The particles contain between 13 and 18 % of boron atoms by weight, which would provide a high amount of 10B nuclides for BNCT, while the polymer chains are suitable for further modification with cell targeting ligands.

Tracing reclaimed water in the Menifee, Winchester, and Perris-South ground-water subbasins, Riverside County, California

USGS Publications Warehouse

Kaehler, Charles A.; Belitz, Kenneth

2003-01-01

As a component in the management of water resources in the Menifee, Winchester, and Perris-South subbasins in Riverside County, California, ponds are operated by the Eastern Municipal Water District for the temporary storage of reclaimed water that is produced by several regional water-reclamation facilities. A primary goal of this study was to evaluate the potential for using various ground-water constituents or characteristics as tracers of reclaimed water that has infiltrated from the storage ponds into the ground water in the three subbasins. A secondary goal was to estimate the degree to which the infiltrated reclaimed water has mixed with the native ground water. The evaluation of potential tracers and the estimation of mixing focused on data from wells located relatively close to the ponds. The most useful constituents and characteristics for evaluation of the fate and mixing of reclaimed water in the Menifee, Winchester, and Perris-South subbasins are major-ion composition, stable isotopes of hydrogen and oxygen, ultraviolet absorbance (UV-A), chloride concentration, and boron/chloride ratio plotted against chloride concentration. Emphasis in this study was placed on evaluating the utility of UV-A as a tracer and boron/chloride ratios in estimating the fraction of reclaimed water in ground water. In the Menifee subbasin, major-ion data, stable isotopes, chloride, UV-A, and boron/chloride ratio are all useful in identifying reclaimed water, and the results based on these indicators are consistent with each other. The results suggest that values of UV-A greater than or equal to 0.007 indicate the presence of reclaimed water in the Menifee subbasin. Ground-water samples with UV-A greater than 0.007 are estimated to consist of about 75 to 100 percent reclaimed water, on the basis of chloride-mixing calculations and boron/chloride-versus-chloride mixing calculations. In the Winchester subbasin, results based on the same factors used in the Menifee subbasin are less conclusive; nevertheless, UV-A can be used as a tracer. The results suggest that values of UV-A greater than 0.01 indicate the presence of reclaimed water. Values from 0.006 to 0.01 may indicate the presence of reclaimed water; however, water from wells not likely to have reclaimed water may also have UV-A values in this range. Ground-water samples with UV-A greater than 0.01 seem to contain about 25 percent reclaimed water (range 6 to 32 percent), on the basis of the consistency of the results of three types of mixing calculations--chloride alone, boron/chloride versus chloride, and UV-A. In the Perris-South subbasin, the potential tracers are not as conclusive in identifying reclaimed water in the subsurface as in the Menifee and Winchester subbasins. The less-conclusive results are a consequence of the multiple, spatially distributed sources of reclaimed water; the relative absence of wells close to the reclaimed-water pond; and the short period of operation (about 1 year) of the pond at the time of sampling. Mixing calculations suggest that ground-water samples with elevated UV-A values (greater than 0.01) in the Perris-South subbasin could contain as much as 40 to 65 percent reclaimed water.

Roll-on perfume compositions containing polyoxybutylene-polyoxyethylene copolymers

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

Schmolka, I.R.

1987-05-26

This patent describes a liquid roll-on composition containing, in weight percent based upon the total composition weight, from 5 percent to 15 percent of a perfume oil, from 25 percent to 40 percent of a volatile alcohol, from 10 percent to 60 percent water, and from 10 percent to 30 percent of a nonionic polyether surfactant. The improvement comprises employing as the nonionic polyether surfactant a cogeneric polyoxybutylene-polyoxyethylene block copolymer.

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium using inductively coupled plasma-mass spectrometry

USGS Publications Warehouse

Garbarino, John R.

1999-01-01

The inductively coupled plasma?mass spectrometric (ICP?MS) methods have been expanded to include the determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium in filtered, acidified natural water. Method detection limits for these elements are now 10 to 200 times lower than by former U.S. Geological Survey (USGS) methods, thus providing lower variability at ambient concentrations. The bias and variability of the method was determined by using results from spike recoveries, standard reference materials, and validation samples. Spike recoveries at 5 to 10 times the method detection limit and 75 micrograms per liter in reagent-water, surface-water, and groundwater matrices averaged 93 percent for seven replicates, although selected elemental recoveries in a ground-water matrix with an extremely high iron sulfate concentration were negatively biased by 30 percent. Results for standard reference materials were within 1 standard deviation of the most probable value. Statistical analysis of the results from about 60 filtered, acidified natural-water samples indicated that there was no significant difference between ICP?MS and former USGS official methods of analysis.

Zinc oxide varistors and/or resistors

DOEpatents

Arnold, W.D. Jr.; Bond, W.D.; Lauf, R.J.

1993-07-27

Varistors and/or resistors are described that include doped zinc oxide gel microspheres. The doped zinc oxide gel microspheres preferably have from about 60 to about 95% by weight zinc oxide and from about 5 to about 40% by weight dopants based on the weight of the zinc oxide. The dopants are a plurality of dopants selected from silver salts, boron oxide, silicon oxide and hydrons oxides of aluminum, bismuth, cobalt, chromium, manganese, nickel, and antimony.

Zinc oxide varistors and/or resistors

DOEpatents

Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

1993-01-01

Varistors and/or resistors that includes doped zinc oxide gel microspheres. The doped zinc oxide gel microspheres preferably have from about 60 to about 95% by weight zinc oxide and from about 5 to about 40% by weight dopants based on the weight of the zinc oxide. The dopants are a plurality of dopants selected from silver salts, boron oxide, silicon oxide and hydrons oxides of aluminum, bismuth, cobalt, chromium, manganese, nickel, and antimony.

Chemical and structural characterization of boron carbide powders and ceramics

NASA Astrophysics Data System (ADS)

Kuwelkar, Kanak Anant

Boron carbide is the material of choice for lightweight armor applications due to its extreme hardness, high Young's modulus and low specific weight. The homogeneity range in boron carbide extends from 9 to 20 at% carbon with the solubility limits not uniquely defined in literature. Over the homogeneity range, the exact lattice positions of boron and carbon atoms have not been unambiguously established, and this topic has been the consideration of significant debate over the last 60 years. The atomic configuration and positions of the boron and carbon atoms play a key role in the crystal structure of the boron carbide phases. Depending on the atomic structure, boron carbide exhibits different mechanical properties which may alter its ballistic performance under extreme dynamic conditions. This work focusses on refinement and development of analytical and chemical methods for an accurate determination of the boron carbide stoichiometry. These methods were then utilized to link structural changes of boron carbide across the solubility range to variations in mechanical properties. After an extensive assessment of the currently employed characterization techniques, it was discerned that the largest source of uncertainty in the determination of the boron carbide stoichiometry was found to arise from the method utilized to evaluate the free carbon concentration. To this end, a modified spiking technique was introduced for free carbon determination where curve fitting techniques were employed to model the asymmetry of the 002 free carbon diffraction peak based on the amorphous, disordered and graphitic nature of carbon. A relationship was then established between the relative intensities of the carbon and boron carbide peaks to the percentage of added carbon and the free-carbon content was obtained by extrapolation. Samples with varying chemistry and high purity were synthesized across the solubility range by hot pressing mixtures of amorphous boron and boron carbide. Vibrational mode frequencies and lattice parameter measurements from Rietveld refinement were correlated to the respective B:C ratios calculated using the developed characterization techniques. An expansion of the unit cell and change in slope in the lattice parameter-stoichiometry relationship were observed at more boron rich stoichiometries. These observations were justified through the proposal of a simplified structural model considering preferential substitution of boron atoms for carbon atoms in the icosahedra from 20 at% to 13.3 at% carbon, followed by formation of B-B bonds from 13.3 at % C to 9 at% C. Hardness measurements uncovered decreased hardness values in boron rich boron carbide which was attributed to the formation of weaker unit cells. Load induced amorphization was also detected in all the indented materials. Finally, experimental observations have shown that failure in boron carbide may be governed by a mechanism other than amorphization and synthesizing boron carbide with a modified microstructure at stoichiometries close to B4C may be the way forward to attain improved ballistic performance.

76 FR 49726 - Continuation of Antidumping and Countervailing Duty Orders: Stainless Steel Sheet and Strip in...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-11

... between 0.20 and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent... percent, phosphorus of no more than 0.045 percent, sulfur of no more than 0.03 percent, lanthanum of less....05 percent or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less. This...

75 FR 76700 - Stainless Steel Sheet and Strip in Coils From Taiwan: Final Results of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-09

... percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent or less, silicon of... percent, phosphorus of no more than 0.045 percent, sulfur of no more than 0.03 percent, lanthanum of less....05 percent or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less. This...

12 CFR 217.52 - Simple risk-weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... greater than or equal to −1 (that is, between zero and −1), then E equals the absolute value of RVC. If... this section) by the lowest applicable risk weight in this paragraph (b). (1) Zero percent risk weight... credit exposures receive a zero percent risk weight under § 217.32 may be assigned a zero percent risk...

[Effect of drinking boron on microtructure of adrenal gland in rats].

PubMed

Li, Shenghe; Wang, Jue; Zhou, Jinxing; Jin, Guangming; Gu, Youfang; Xu, Wanxiang

2012-09-01

The effects of drinking boron exposure on the mass, organ indexes and structure of adrenal gland were studied in the paper. Methods 192 Sprague-Dawley rats (28 +/- 2 days) with no bacteria infecting were divided into six groups (n = 32, male = female) randomly. Treated rats drunk the distilled water which supplemented with boron of 0, 40, 80, 160, 320 and 640 mg/L, respectively, for 60 days. At the 30th and the 60th day of experiment, 16 rats (n = 8, male = female) of each group were selected and made into narcosis with 10% Chloral Hydrate. The adrenal glands were obtained, weighted and fixed after dissection, then the samples were made into paraffin sections, stained with HE stain and chromaffin, observed and photographed by Olympus CH-30 microphotograph system. Compared with control group, the average mass of adrenal gland of male rats in each experiment group decreased significantly or most significantly at the 30th day of experiment (P < 0.05 or P < 0.01), but the index of adrenal gland of male rats in the group of 640 mg/L boron at 60th day of experiment increased significantly (P < 0.05). Under the microscope, the microstructure of adrenal gland of rats in the group of 40 mg/L boron were better obviously than control group, and the numbers of chromaffin granules in chromaffin cell increased obviously. The histopathological changes of different degree could be observed in the group of 80 to 640 mg/L boron, and they became remarkable with the boron supplementation. By comparative observation, the damage of cells in adrenal medulla appeared ahead of them in adrenal cortex, and the pathological change of adrenal gland in male rats were obvious than female rats. Drinking supplemented with 40 mg/L boron could prompt the structure of adrenal gland in rats, but could cause different degree damage, or even obvious toxic effect when the concentration of boron supplementation in drinking from 80 to 640 mg/L.

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Vermejo Project area and the Maxwell National Wildlife Refuge, Colfax County, northeastern New Mexico, 1993

USGS Publications Warehouse

Bartolino, J.R.; Garrabrant, L.A.; Wilson, Mark; Lusk, J.D.

1996-01-01

Based on findings of limited studies during 1989-92, a reconnaissance investigation was conducted in 1993 to assess the effects of the Vermejo Irrigation Project on water quality in the area of the project, including the Maxwell National Wildlife Refuge. This project was part of a U.S. Department of the Interior National Irrigation Water-Quality Program to determine whether irrigation drainage has caused or has the potential to cause significant harmful effects on human health, fish, and wildlife and whether irrigation drainage may adversely affect the suitability of water for other beneficial uses. For this study, samples of water, sediment, and biota were collected from 16 sites in and around the Vermejo Irrigation Project prior to, during the latter part of, and after the 1993 irrigation season (April, August-September, and November, respectively). No inorganic constituents exceeded U.S. Environmental Protection Agency drinking-water standards. The State of New Mexico standard of 750 micrograms per liter for boron in irrigation water was exceeded at three sites (five samples), though none exceeded the livestock water standard of 5,000 micrograms per liter. Selenium concentrations exceeded the State of New Mexico chronic standard of 2 micrograms per liter for wildlife and fisheries water in at least eight samples from five sites. Bottom-sediment samples were collected and analyzed for trace elements and compared to concentrations of trace elements in soils of the Western United States. Concentrations of three trace elements at eight sites exceeded the upper values of the expected 95-percent ranges for Western U.S. soils. These included molybdenum at one site, selenium at seven sites, and uranium at four sites. Cadmium and copper concentrations exceeded the National Contaminant Biomonitoring Program 85th percentile in fish from six sites. Average concentrations of selenium in adult brine flies (33.7 mg/g dry weight) were elevated above concentrations in other invertebrates. Concentrations of other elements were below their respective toxicity levels. Plants, invertebrates, fish, and fish fillets were collected and analyzed. These analyses were compared to diagnostic criteria and to each other to determine the extent of bioaccumulation of trace elements. Plants contained larger dry weight concentrations of aluminum, arsenic, boron, chromium, iron, lead, magnesium, manganese, nickel, and vanadium than invertebrates and fish. Adult brine flies, gathered from playas, contained larger geometric mean dry weight concentrations of boron, magnesium, and selenium than other invertebrates. Of all samples collected, the largest mercury concentrations were found in fish fillets, although these concentrations were below levels of concern. Mercury and selenium bioaccumulation was evident in various habitats of the study area. Biological samples from Natural playa, an endemic wetland, and Half playa, a playa that receives additional water through seepage and irrigation delivery canals, generally had elevated concentrations of boron, iron, magnesium, and selenium than samples from reservoir and river sites. Selenium concentrations were lowest in biota from the two reservoir sites, although a wetland immediately downstream from the dam impounding Lake No. 13 (created by seepage from the reservoir) had elevated concentrations of selenium in biota. The geometric mean selenium concentration of whole-fish samples, except those from Lakes No. 13 and No. 14, exceeded the 5-mg/g dry weight selenium concentration that demarcates the approximate lower limit of the threshold range of concentrations that have been associated with adverse effects on piscine reproduction. Biota collected on and in the area around Maxwell National Wildlife Refuge contained concentrations of selenium that are in the low

Feasibility study of a small, thorium-based fission power system for space and terrestrial applications

NASA Astrophysics Data System (ADS)

Worrall, Michael Jason

One of the current challenges facing space exploration is the creation of a power source capable of providing useful energy for the entire duration of a mission. Historically, radioisotope batteries have been used to provide load power, but this conventional system may not be capable of sustaining continuous power for longer duration missions. To remedy this, many forays into nuclear powered spacecraft have been investigated, but no robust system for long-term power generation has been found. In this study, a novel spin on the traditional fission power system that represents a potential optimum solution is presented. By utilizing mature High Temperature Gas Reactor (HTGR) technology in conjunction with the capabilities of the thorium fuel cycle, we have created a light-weight, long-term power source capable of a continuous electric power output of up to 70kW for over 15 years. This system relies upon a combination of fissile, highly-enriched uranium dioxide and fertile thorium carbide Tri-Structural Isotropic (TRISO) fuel particles embedded in a hexagonal beryllium oxide matrix. As the primary fissile material is consumed, the fertile material breeds new fissile material leading to more steady fuel loading over the lifetime of the core. Reactor control is achieved through an innovative approach to the conventional boron carbide neutron absorber by utilizing sections of borated aluminum placed in rotating control drums within the reflector. Borated aluminum allows for much smaller boron concentrations, thus eliminating the potential for 10B(n,alpha)6Li heating issues that are common in boron carbide systems. A wide range of other reactivity control systems are also investigated, such as a radially-split rotating reflector. Lastly, an extension of the design to a terrestrial based system is investigated. In this system, uranium enrichment is dropped to 20 percent in order to meet current regulations, a solid uranium-zirconium hydride fissile driver replaces the uranium dioxide TRISO particles, and the moderating material is changed from beryllium oxide to graphite. These changes result in an increased core size, but the same long-term power generation potential is achieved. Additionally, small amounts of erbium are added to the hydride matrix to further extend core lifetime.

7 CFR 51.1586 - Serious damage.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of more than 10 percent of the total weight of the potato including peel covering defective area. Any... percent of the total weight of the potato including peel covering defective area. (b) Shriveling, when the... percent of the total weight of the potato including peel covering defective area. (e) Wireworm, grass root...

7 CFR 51.1586 - Serious damage.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of more than 10 percent of the total weight of the potato including peel covering defective area. Any... percent of the total weight of the potato including peel covering defective area. (b) Shriveling, when the... percent of the total weight of the potato including peel covering defective area. (e) Wireworm, grass root...

12 CFR 3.37 - Collateralized transactions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... this section: (i) A national bank or Federal savings association may assign a zero percent risk weight... qualifies for a zero percent risk weight under § 3.32. (iii) A national bank or Federal savings association may assign a zero percent risk weight to the collateralized portion of an exposure where: (A) The...

40 CFR 98.183 - Calculating GHG emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... = Carbon content of the lead ore, from the carbon analysis results (percent by weight, expressed as a... = Carbon content of the lead scrap, from the carbon analysis (percent by weight, expressed as a decimal... (tons). CFlux = Carbon content of the flux materials, from the carbon analysis (percent by weight...

Iron aluminide alloy container for solid oxide fuel cells

DOEpatents

Judkins, Roddie Reagan; Singh, Prabhakar; Sikka, Vinod Kumar

2000-01-01

A container for fuel cells is made from an iron aluminide alloy. The container alloy preferably includes from about 13 to about 22 weight percent Al, from about 2 to about 8 weight percent Cr, from about 0.1 to about 4 weight percent M selected from Zr and Hf, from about 0.005 to about 0.5 weight percent B or from about 0.001 to about 1 weight percent C, and the balance Fe and incidental impurities. The iron aluminide container alloy is extremely resistant to corrosion and metal loss when exposed to dual reducing and oxidizing atmospheres at elevated temperatures. The alloy is particularly useful for containment vessels for solid oxide fuel cells, as a replacement for stainless steel alloys which are currently used.

Status and understanding of groundwater quality in the North San Francisco Bay groundwater basins, 2004

USGS Publications Warehouse

Kulongoski, Justin T.; Belitz, Kenneth; Landon, Matthew K.; Farrar, Christopher

2010-01-01

Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) North San Francisco Bay study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in northern California in Marin, Napa, and Sonoma Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA North San Francisco Bay study was designed to provide a spatially unbiased assessment of untreated groundwater quality in the primary aquifer systems. The assessment is based on water-quality and ancillary data collected by the USGS from 89 wells in 2004 and water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer systems (hereinafter referred to as primary aquifers) were defined by the depth interval of the wells listed in the CDPH database for the North San Francisco Bay study unit. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOC), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifers of the North San Francisco Bay study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or) California benchmarks. A relative-concentration greater than (>) 1.0 indicates a concentration above a benchmark, and less than or equal to (=) 1.0 indicates a concentration equal to or below a benchmark. Relative-concentrations of organic and special interest constituents were classified as ?high? (relative-concentration > 1.0), ?moderate? (0.1 1.0), ?moderate? (0.5 < relative-concentration = 1.0), or ?low? (relative-concentration = 0.5). Aquifer-scale proportion was used as a metric for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the primary aquifers that have a relative-concentration greater than 1.0; proportion is calculated on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentage of the primary aquifers that have moderate and low relative-concentrations, respectively. Two statistical approaches-grid-based and spatially-weighted-were used to evaluate aquifer-scale proportion for individual constituents and classes of constituents. Grid-based and spatially-weighted estimates were comparable in the North San Francisco Bay study unit (90-percent confidence intervals). For inorganic constituents with human-health benchmarks, relative-concentrations were high in 14.0 percent of the primary aquifers, moderate in 35.8 percent, and low in 50.2 percent. The high aquifer-scale proportion of inorganic constituents primarily reflected high aquifer-scale proportions of arsenic (10.0 percent), boron (4.1 percent), and lead (1.6 percent). In contrast, relative-concentrations of organic constituents (one or more) were high in 1.4 percent, moderate in 4.9 percent, and low in 93.7 percent (not detected in 64.8 percent) of the primary aquifers. The high aquifer-scale proport

Neutron absorbing coating for nuclear criticality control

DOEpatents

Mizia, Ronald E.; Wright, Richard N.; Swank, William D.; Lister, Tedd E.; Pinhero, Patrick J.

2007-10-23

A neutron absorbing coating for use on a substrate, and which provides nuclear criticality control is described and which includes a nickel, chromium, molybdenum, and gadolinium alloy having less than about 5% boron, by weight.

Boric acid enhances in vivo Ehrlich ascites carcinoma cell proliferation in Swiss albino mice.

PubMed

Qureshi, S; Al-Shabanah, O A; Al-Harbi, M M; Al-Bekairi, A M; Raza, M

2001-08-13

The influence of boric acid, a boron carrier, on Ehrlich ascites carcinoma (EAC) cell-bearing mice was investigated in view of its importance in the boron neutron capture therapy and the influence of boron on proliferation and progression of cancer cells mediated by proteoglycans and collagen. The present study included the evaluation of boric acid for the effects on total count and viability of EAC cells in addition to their non-protein sulfhydryls (NP-SH) and malondialdehyde (MDA) contents as parameters for conjugative detoxication potency and possible oxidative damage. The EAC cell-bearing animals were also observed for the effect on survival, body weight changes, and histopathological evaluation of the tumors grown at the site of inoculation. The treatment with boric acid significantly increased the total number of peritoneal EAC cells and their viability. A significant increase in the body weight was observed that dose-dependently reached plateau levels by 20 days of treatment. Conversely, a reduction in the duration of survival of these animals was evident with the same protocol. Boric acid treatment resulted in a decrease in NP-SH contents with a concomitant increase in MDA levels in EAC cells as revealed by the results of the biochemical analysis. These data are supported by our results on histopathological investigations, which apparently showed fast growth, in addition to several mitotic figures and mixed inflammatory reaction, after treatment with boric acid. It seems likely that a particular combination of properties of boric acid, rather than a single characteristic alone, will provide useful information on the use of this boron carrier in neutron capture therapy.

Weldable, age hardenable, austenitic stainless steel

DOEpatents

Brooks, J.A.; Krenzer, R.W.

1975-07-22

An age hardenable, austenitic stainless steel having superior weldability properties as well as resistance to degradation of properties in a hydrogen atmosphere is described. It has a composition of from about 24.0 to about 34.0 weight percent (w/o) nickel, from about 13.5 to about 16.0 w/o chromium, from about 1.9 to about 2.3 w/o titanium, from about 1.0 to about 1.5 w/ o molybdenum, from about 0.01 to about 0.05 w/o carbon, from about 0 to about 0.25 w/o manganese, from about 0 to about 0.01 w/o phosphorous and preferably about 0.005 w/o maximum, from about 0 to about 0.010 w/o sulfur and preferably about 0.005 w/o maximum, from about 0 to about 0.25 w/o silicon, from about 0.1 to about 0.35 w/o aluminum, from about 0.10 to about 0.50 w/o vanadium, from about 0 to about 0.0015 w/o boron, and the balance essentially iron. (auth)

Design of a unidirectional composite momentum wheel rim

NASA Astrophysics Data System (ADS)

Shogrin, Bradley; Jones, William R., Jr.; Prahl, Joseph M.

1995-05-01

A preliminary study comparing twelve unidirectional-fiber composite systems to five metal materials conventionally used in momentum wheels is presented. Six different fibers are considered in the study: E-Glass, S-Glass, Boron, AS, T300, and Kevlar. Because of the possibility of high momentum requirements, and thus high stresses, only two matrix materials are considered: a high-modulus (HM) and a intermediate-modulus-high-strength (IMHS) matrix. Each of the six fibers are coupled with each of the two matrix materials. In an effort to optimize the composite system, each composite is considered while varying the fiber volume ratio from 0.0 to 0.7 in increments of 0.1. For fiber volume ratios above 0.2, all twelve unidirectional-fiber composite systems meet the study's requirements with higher factors of safety and less mass than the five conventional isotropic (metal) materials. For example, at a fiber volume ratio of 0.6, the Kevlar/IMHS composite system has a safety factor 4.5 times greater than that of a steel (maraging) system and an approximately 10 percent reduction in weight.

Design of cemented tungsten carbide and boride-containing shields for a fusion power plant

NASA Astrophysics Data System (ADS)

Windsor, C. G.; Marshall, J. M.; Morgan, J. G.; Fair, J.; Smith, G. D. W.; Rajczyk-Wryk, A.; Tarragó, J. M.

2018-07-01

Results are reported on cemented tungsten carbide (cWC) and boride-containing composite materials for the task of shielding the centre column of a superconducting tokamak power plant. The shield is based on five concentric annular shells consisting of cWC and water layers of which the innermost cWC shield can be replaced with boride composites. Sample materials have been fabricated changing the parameters of porosity P, binder alloy fraction f binder and boron weight fraction f boron. For the fabricated materials, and other hypothetical samples with chosen parameters, Monte Carlo studies are made of: (i) the power deposition into the superconducting core, (ii) the fast neutron and gamma fluxes and (iii) the attenuation coefficients through the shield for the deposited power and neutron and gamma fluxes. It is shown that conventional Co-based cWC binder alloy can be replaced with a Fe–Cr alloy (92 wt.% Fe, 8 wt.% Cr), which has lower activation than cobalt with minor changes in shield performance. Boride-based composite materials have been prepared and shown to give a significant reduction in power deposition and flux, when placed close to the superconducting core. A typical shield of cemented tungsten carbide with 10 wt.% of Fe–8Cr binder and 0.1% porosity has a power reduction half-length of 0.06 m. It is shown that the power deposition increases by 4.3% for every 1% additional porosity, and 1.7% for every 1 wt.% additional binder. Power deposition decreased by 26% for an initial 1 wt.% boron addition, but further increases in f boron showed only a marginal decrease. The dependences of power deposited in the core, the maximum neutron and gamma fluxes on the core surface, and the half attenuation distances through the shield have been fitted to within a fractional percentage error by analytic functions of the porosity, metallic binder alloy and boron weight fractions.

Nanoporous Boron Nitride as Exceptionally Thermally Stable Adsorbent: Role in Efficient Separation of Light Hydrocarbons.

PubMed

Saha, Dipendu; Orkoulas, Gerassimos; Yohannan, Samuel; Ho, Hoi Chun; Cakmak, Ercan; Chen, Jihua; Ozcan, Soydan

2017-04-26

In this work, nanoporous boron nitride sample was synthesized with a Brunauer-Emmett-Teller (BET) surface area of 1360 m 2 /g and particle size 5-7 μm. The boron nitride was characterized with X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electron microscopy (TEM and SEM). Thermogravimetric analysis (TGA) under nitrogen and air and subsequent analysis with XPS and XRD suggested that its structure is stable in air up to 800 °C and in nitrogen up to 1050 °C, which is higher than most of the common adsorbents reported so far. Nitrogen and hydrocarbon adsorption at 298 K and pressure up to 1 bar suggested that all hydrocarbon adsorption amounts were higher than that of nitrogen and the adsorbed amount of hydrocarbon increases with an increase in its molecular weight. The kinetics of adsorption data suggested that adsorption becomes slower with the increase in molecular weight of hydrocarbons. The equilibrium data suggested that that boron nitride is selective to paraffins in a paraffin-olefin mixture and hence may act as an "olefin generator". The ideal adsorbed solution theory (IAST)-based selectivity for CH 4 /N 2 , C 2 H 6 /CH 4 , and C 3 H 8 /C 3 H 6 was very high and probably higher than the majority of adsorbents reported in the literature. IAST-based calculations were also employed to simulate the binary mixture adsorption data for the gas pairs of CH 4 /N 2 , C 2 H 6 /CH 4 , C 2 H 6 /C 2 H 4 , and C 3 H 8 /C 3 H 6 . Finally, a simple mathematical model was employed to simulate the breakthrough behavior of the above-mentioned four gas pairs in a dynamic column experiment. The overall results suggest that nanoporous boron nitride can be used as a potential adsorbent for light hydrocarbon separation.

75 FR 6627 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

... between 0.20 and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent... 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent..., manganese, silicon and molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur...

78 FR 79667 - Stainless Steel Sheet and Strip in Coils From Japan: Initiation of Expedited Changed...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-31

... weight, phosphorus of 0.025 percent or less, silicon of between 0.20 and 0.50 percent, and sulfur of 0... 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent..., manganese, silicon and molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur...

75 FR 81214 - Stainless Steel Sheet and Strip in Coils From Italy: Preliminary Results of the Full Second Five...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-27

... between 0.20 and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent... 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent..., manganese, silicon and molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur...

High strength ferritic alloy-D53

DOEpatents

Hagel, William C.; Smidt, Frederick A.; Korenko, Michael K.

1977-01-01

A high strength ferritic alloy is described having from about 0.2% to about 0.8% by weight nickel, from about 2.5% to about 3.6% by weight chromium, from about 2.5% to about 3.5% by weight molybdenum, from about 0.1% to about 0.5% by weight vanadium, from about 0.1% to about 0.5% by weight silicon, from about 0.1% to about 0.6% by weight manganese, from about 0.12% to about 0.20% by weight carbon, from about 0.02% to about 0.1% by weight boron, a maximum of about 0.05% by weight nitrogen, a maximum of about 0.02% by weight phosphorous, a maximum of about 0.02% by weight sulfur, and the balance iron.

Mathematical and statistical analysis of the effect of boron on yield parameters of wheat

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

Rawashdeh, Hamzeh; Sala, Florin; Boldea, Marius

The main objective of this research is to investigate the effect of foliar applications of boron at different growth stages on yield and yield parameters of wheat. The contribution of boron in achieving yield parameters is described by second degree polynomial equations, with high statistical confidence (p<0.01; F theoretical < F calculated, according to ANOVA test, for Alfa = 0.05). Regression analysis, based on R{sup 2} values obtained, made it possible to evaluate the particular contribution of boron to the realization of yield parameters. This was lower for spike length (R{sup 2} = 0.812), thousand seeds weight (R{sup 2} =more » 0.850) and higher in the case of the number of spikelets (R{sup 2} = 0.936) and the number of seeds on a spike (R{sup 2} = 0.960). These results confirm that boron plays an important part in achieving the number of seeds on a spike in the case of wheat, as the contribution of this element to the process of flower fertilization is well-known. In regards to productivity elements, the contribution of macroelements to yield quantity is clear, the contribution of B alone being R{sup 2} = 0.868.« less

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

Herbel, J.L.; Hunt, C.D.

An experiment was designed to test the hypothesis that dietary boron impacts upon the function of various coenzymes involved in energy metabolism. In a 2 {times} 7 factorially-arranged experiment, weanling, vitamin D{sub 3}-deprived rats were fed a ground corn-casein-corn oil based diet supplemented with 0 or 2 mg boron/kg and 50% of the requirement for thiamine (TM), riboflavin (RF), pantothenic acid (PA) or pyridoxine (PX); 0% for folic acid (FA) or nicotinic acid (NA). All vitamins were supplemented in adequate amounts in the control diet. At 8 weeks of age, the TM dietary treatment was the one most affected bymore » supplemental dietary boron (SDB). In rats that were fed 50% TM, SDB increased plasma concentrations of triglyceride (TG) and activity of alanine transaminase (ALT), and the liver to body weight (L/B) ratio. However, in the SDB animals, adequate amounts of TM decreased the means of those variables to near that observed in non-SDB rats fed 50% TM. The findings suggest that an interaction between dietary boron and TM affects lipid metabolism.« less

Boron-Containing Compounds for Liposome-Mediated Tumor Localization and Application to Neutron Capture Therapy

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

Hawthorne, M. Frederick

2005-04-07

Medical application of boron neutron capture therapy (BNCT) has been significantly hindered by the slow development of boron drug-targeting methodologies for the selective delivery of high boron concentration sto malignant cells. We have successfully sought to fill this need by creating liposomes suitable as in vivo boron delivery vehicles for BNCT. Delivery of therapeutic quantities of boron to tumors in murine models has been achieved with small unilamellar boron-rich liposomes. Subsequently, attempts have been made to improve delivery efficiency of liposomes encapsulating boron-containing water-soluble species into their hollow core by incorporating lipophilic boron compounds as addenda to the liposome bilayer,more » incorporating boron compounds as structural components of the bilayer (which however, poses the risk of sacrificing some stability), and combinations thereof. Regardless of the method, approximately 90% of the total liposome mass remains therapeutically inactive and comprised of the vehicle's construction materials, while less than 5% is boron for neutron targeting. Following this laboratory's intensive study, the observed tumor specificity of certain liposomes has been attributed to their diminutive size of these liposomes (30-150 nm), which enables these small vesicles to pass through the porous, immature vasculature of rapidly growing tumor tissue. We surmised that any amphiphilic nanoparticle of suitable size could possess some tumor selectivity. Consequently, the discovery of a very boron-rich nanoparticle delivery agent with biodistribution performance similar to unilamellar liposomes became one of our goals. Closomers, a new class of polyhedral borane derivatives, attracted us as an alternative BNCT drug-delivery system. We specifically envisioned dodeca (nido-carboranyl)-substituted closomers as possibly having a great potential role in BNCT drug delivery. They could function as extraordinarily boron-rich BNCT drugs since they are amphiphilic unimolecular nanoparticles presenting several advantages: tunable size through functionalization and branching, spherical shape due to the icosahedral B122 core, promising water solubility resulting from degradation of all pendant closo-carborane groups to their hydrophilic nido anion substituents, and efficient boron delivery owing to the presence of 120 boron atoms which gives rise to a boron content as high as 40% by weight. Keeping the new objective in mind, we have focused on the design, synthesis and evaluation of new and very boron-rich closomer species. Additionally, progress has also been made toward the evaluation of a newly synthesized boron-rich lipid as a substitute for DSPC in bilayer construction, and the boron content of the resulting liposomes has been greatly enhanced. Related research involving the synthesis and self-assembly of carborane-containing amphiphiles has been systematically studied. Combined hydrophobic and hydrophilic properties of the single-chain amphiphiles allow their spontaneous self-assembly to form rods under a variety of variable conditions, such as concentration in the bilayer, carborane cage structure, chain-length, counterion identity, solvents, methods of preparation, and the ionic charge. On the other hand, the number of attached chains affects the self-assembly process. Particles having totally different shapes have been observed for dual-chain amphiphiles.« less

Drop-in substitute for dichlorodifluoromethane refrigerant

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

Goble, G.H.

1993-06-01

A method for producing refrigeration in a refrigeration system designed for a dichlorodifluoromethane refrigerant is described, comprising drop-in substituting for said dichlorodifluoromethane a ternary mixture of about 2 to 20 weight percent isobutane, about 21 to 51 weight percent 1-chloro-1,1-difluoroethane, and about 41 to 71 weight percent chlorodifluoromethane, with the weight percentages of said components being weight percentages of the overall mixture; condensing said ternary mixture; and thereafter evaporating said ternary mixture in the vicinity of a body to be cooled.

7 CFR 52.1845 - Sizes of seedless raisins.

Code of Federal Regulations, 2013 CFR

2013-01-01

... percent, by weight, of all the raisins will pass through round perforations 22/64-inch in diameter, but not more than 10 percent, by weight, of all the raisins may pass through round perforations 20/64-inch... will pass through round perforations 24/64-inch in diameter, and not less than 70 percent, by weight...

7 CFR 52.1845 - Sizes of seedless raisins.

Code of Federal Regulations, 2014 CFR

2014-01-01

... percent, by weight, of all the raisins will pass through round perforations 22/64-inch in diameter, but not more than 10 percent, by weight, of all the raisins may pass through round perforations 20/64-inch... will pass through round perforations 24/64-inch in diameter, and not less than 70 percent, by weight...

7 CFR 52.1846 - Grades of seedless raisins.

Code of Federal Regulations, 2011 CFR

2011-01-01

... more than 18 percent, by weight, of moisture for all varieties of seedless raisins except the Monukka variety, which may contain not more than 19 percent, by weight, of moisture; and that meet the additional...-matured; that contain not more than 18 percent, by weight, of moisture for all varieties of seedless...

7 CFR 52.1846 - Grades of seedless raisins.

Code of Federal Regulations, 2012 CFR

2012-01-01

... more than 18 percent, by weight, of moisture for all varieties of seedless raisins except the Monukka variety, which may contain not more than 19 percent, by weight, of moisture; and that meet the additional...-matured; that contain not more than 18 percent, by weight, of moisture for all varieties of seedless...

12 CFR 324.37 - Collateralized transactions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... institution may assign a zero percent risk weight to an exposure to an OTC derivative contract that is marked... exposure to a sovereign that qualifies for a zero percent risk weight under § 324.32. (iii) An FDIC-supervised institution may assign a zero percent risk weight to the collateralized portion of an exposure...

Design of a large span-distributed load flying-wing cargo airplane with laminar flow control

NASA Technical Reports Server (NTRS)

Lovell, W. A.; Price, J. E.; Quartero, C. B.; Turriziani, R. V.; Washburn, G. F.

1978-01-01

A design study was conducted to add laminar flow control to a previously design span-distributed load airplane while maintaining constant range and payload. With laminar flow control applied to 100 percent of the wing and vertical tail chords, the empty weight increased by 4.2 percent, the drag decreased by 27.4 percent, the required engine thrust decreased by 14.8 percent, and the fuel consumption decreased by 21.8 percent. When laminar flow control was applied to a lesser extent of the chord (approximately 80 percent), the empty weight increased by 3.4 percent, the drag decreased by 20.0 percent, the required engine thrust decreased by 13.0 percent, and the fuel consumption decreased by 16.2 percent. In both cases the required take-off gross weight of the aircraft was less than the original turbulent aircraft.

Use of boron cluster-containing redox nanoparticles with ROS scavenging ability in boron neutron capture therapy to achieve high therapeutic efficiency and low adverse effects.

PubMed

Gao, Zhenyu; Horiguchi, Yukichi; Nakai, Kei; Matsumura, Akira; Suzuki, Minoru; Ono, Koji; Nagasaki, Yukio

2016-10-01

A boron delivery system with high therapeutic efficiency and low adverse effects is crucial for a successful boron neutron capture therapy (BNCT). In this study, we developed boron cluster-containing redox nanoparticles (BNPs) via polyion complex (PIC) formation, using a newly synthesized poly(ethylene glycol)-polyanion (PEG-polyanion, possessing a (10)B-enriched boron cluster as a side chain of one of its segments) and PEG-polycation (possessing a reactive oxygen species (ROS) scavenger as a side chain of one of its segments). The BNPs exhibited high colloidal stability, selective uptake in tumor cells, specific accumulation, and long retention in tumor tissue and ROS scavenging ability. After thermal neutron irradiation, significant suppression of tumor growth was observed in the BNP-treated group, with only 5-ppm (10)B in tumor tissues, whereas at least 20-ppm (10)B is generally required for low molecular weight (LMW) (10)B agents. In addition, increased leukocyte levels were observed in the LMW (10)B agent-treated group after thermal neutron irradiation, and not in BNP-treated group, which might be attributed to its ROS scavenging ability. No visual metastasis of tumor cells to other organs was observed 1 month after irradiation in the BNP-treated group. These results suggest that BNPs are promising for enhancing the BNCT performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Oven rack having integral lubricious, dry porcelain surface

DOEpatents

Ambrose, Jeffrey A; Mackiewicz-Ludtka, Gail; Sikka, Vinod K; Qu, Jun

2014-06-03

A lubricious glass-coated metal cooking article capable of withstanding repeated heating and cooling between room temperature and at least 500.degree. F. without chipping or cracking the glass coating, wherein the glass coating includes about 0.1 to about 20% by weight of a homogeneously distributed dry refractory lubricant material having a particle size less than about 200 .mu.m. The lubricant material is selected from the group consisting of carbon; graphite; boron nitride; cubic boron nitride; molybdenum (FV) sulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide, tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si.sub.3N.sub.4); TiN; TiC; TiCN; TiO.sub.2; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO.sub.2); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.

Orbital Payload Reductions Resulting from Booster and Trajectory Modifications for Recovery of a Large Rocket Booster

NASA Technical Reports Server (NTRS)

Levin, Alan D.; Hopkins, Edward J.

1961-01-01

An analysis was made to determine the reduction in payload for a 300 nautical mile orbit resulting from the addition of inert weight, representing recovery gear, to the first-stage booster of a three-stage rocket vehicle. The values of added inert weight investigated ranged from 0 to 18 percent of gross weight at lift off. The study also included the effects on the payload in orbit and the distance from the launch site at burnout and at impact caused by variation in the vertical rise time before the programmed tilt. The vertical rise times investigated ranged from 16-7 to 100 percent of booster burning time. For a vertical rise of 16.7 percent of booster burning time it was found that a 50-percent increase in the weight of the empty booster resulted in only a 10-percent reduction of the payload in orbit. For no added booster weight, increasing vertical rise time from 16-7 to 100 percent of booster burning time (so that the spent booster would impact in the launch area) reduced the payload by 37 percent. Increasing the vertical rise time from 16-7 to 50 percent of booster burning time resulted in about a 15-percent reduction in the impact distance, and for vertical rise times greater than 50-percent the impact distance decreased rapidly.

75 FR 62104 - Certain Stainless Steel Sheet and Strip in Coils From Germany, Japan, the Republic of Korea, and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-07

... also contains, by weight, phosphorus of 0.025 percent or less, silicon of between 0.20 and 0.50 percent..., chromium of between 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0... percent or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less. This steel...

75 FR 81221 - Stainless Steel Sheet and Strip in Coils From Mexico; Preliminary Results of the Five-Year...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-27

... also contains, by weight, phosphorus of 0.025 percent or less, silicon of between 0.20 and 0.50 percent..., chromium of between 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0... percent or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less. This steel...

76 FR 25670 - Stainless Steel Sheet and Strip in Coils From Italy: Final Results of the Full Five-Year (“Sunset...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-05

... weight, phosphorus of 0.025 percent or less, silicon of between 0.20 and 0.50 percent, and sulfur of 0... 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent..., manganese, silicon and molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur...

BUNDLE: A Novel Furnace for Performing Controlled Directional Solidification Experiments in a Microgravity Environment

NASA Technical Reports Server (NTRS)

Carrasquillo, Edgar J.; Griffin, Mark R.; Hammond, Monica S.; Johnson, Martin L.; Grugel, R. N.

2000-01-01

NASA Marshall Space Flight Center has developed a novel directional solidification furnace prototype for processing metals and alloys experiments in a microgravity environment. The BUNDLE (Bridgman Unidirectional Dendrite in Liquid Experiment) furnace is intended to accommodate the science requirements of Flight Definition Principle Investigators studying cellular/dendritic growth in aluminum and lead alloys at processing temperatures up to 1200 C. The furnace implements a number of innovative features to achieve high thermal gradients and quench rates in a low-power, light-weight design. These include a pyrolytic boron nitride/graphite composite heating element surrounded by layers of self-supporting refractory metal shielding, and a graphite fiber enhanced cold zone allowing high levels of heat extraction from the sample crucible. Novel to the BUNDLE design is an in-situ helium gas quench capability that ensures rapid freezing of the solidifying region (mushy zone) of the metal sample within the furnace without sample disturbance prior to quenching; this is a stringent requirement for subsequent analysis and understanding of microstructural development. The experiment hardware concept features multiple furnaces that may be "bundled" together so many samples, currently up to eight, can be processed at one time. The design of BUNDLE is flexible enough to be implemented on the Shuttle and Space Station in a number of locations (SpaceHab, Express Rack, MPESS, ISPR, etc). BUNDLE prototype furnaces have directionally solidified and quenched 1cm diameter lead - 5.8 weight percent antimony and aluminum - 4 weight percent copper alloys. Quenching of the mushy zone, as recorded by in-situ thermocouples, occurred on the order of 0.5 seconds or less, a rate within the PI's requirements. Subsequent metallographic examination revealed the solidified microstructure to be, as expected, unidirectional. Both the dendrite tips and the eutectic reaction were planar in nature indicating uniform axial heat flow. Delineation between the growing dendrites and eutectic structure with the "quenched-in" liquid was sharp, attesting to the efficacy of the helium quench. BUNDLE's conception, development, capability, and adaptability are presented (in view of Flight PI's needs and science requirements) through viewgraphs depicting actual hardware, generated thermal analysis, and micrographs prepared from BUNDLE processed, flight-like samples.

BUNDLE - A Novel Furnace for Performing Controlled Directional Solidification Experiments in a Microgravity Environment

NASA Technical Reports Server (NTRS)

Carrasquillo, Edgar J.; Griffin, Mark R.; Hammond, Monica S.; Johnson, Martin L.; Grugel, R. N.

2001-01-01

NASA Marshall Space Flight Center has developed a novel directional solidification furnace prototype for processing metals and alloys experiments in a microgravity environment. The BUNDLE (Bridgman Unidirectional Dendrite in Liquid Experiment) furnace is intended to accommodate the science requirements of Flight Definition Principle Investigators studying cellular/dendritic growth in aluminum and lead alloys at processing temperatures up to 1200 C. The furnace implements a number of innovative features to achieve high thermal gradients and quench rates in a low-power, light-weight design. These include a pyrolytic boron nitride/graphite composite heating element surrounded by layers of self-supporting refractory metal shielding, and a graphite fiber enhanced cold zone allowing high levels of heat extraction from the sample crucible. Novel to the BUNDLE design is an in-situ helium gas quench capability that ensures rapid freezing of the solidifying region (mushy zone) of the metal sample within the furnace without sample disturbance prior to quenching; this is a stringent requirement for subsequent analysis and understanding of microstructural development. The experiment hardware concept features multiple furnaces that may be "bundled" together so many samples, currently up to eight, can be processed at one time. The design of BUNDLE is flexible enough to be implemented on the Shuttle and Space Station in a number of locations (SpaceHab, Express Rack, MPESS, ISPR, etc). BUNDLE prototype furnaces have directionally solidified and quenched 1cm diameter lead - 5.8 weight percent antimony and aluminum - 4 weight percent copper alloys. Quenching of the mushy zone, as recorded by in-situ thermocouples, occurred on the order of 0.5 seconds or less, a rate within the PI's requirements. Subsequent metallographic examination revealed the solidified microstructure to be, as expected, unidirectional. Both the dendrite tips and the eutectic reaction were planar in nature indicating uniform axial heat flow. Delineation between the growing dendrites and eutectic structure with the "quenched-in" liquid was sharp, attesting to the efficacy of the helium quench. BUNDLE's conception, development, capability, and adaptability are presented (in view of Flight PI's needs and science requirements) through viewgraphs depicting actual hardware, generated thermal analysis, and micrographs prepared from BUNDLE processed, flight-like samples.

Effect of boron on fruit quality in pineapple

NASA Astrophysics Data System (ADS)

Wei, Changbin; Ma, Zhiling; Liu, Yuge; Qiao, Jian; Sun, Guangming

2018-04-01

Boron (B) is an important element for the plant. The aim of work was to study the effect of B on fruit quality of pineapple. The experiment was carried out with `Comte de paris' variety in pots. The results demonstrated that B had positive effect on fruit weight, TSS, the ratio of TSS/acidity, Vitamin C, the content of aroma volatile compounds. The B had no effect on the content of the three sugars (sucrose, fructose and glucose) and titrable acidity. There was a positive effect on fruit quality by application of B fertilizer in production of pineapple.

Using Mid-Upper Arm Circumference to End Treatment of Severe Acute Malnutrition Leads to Higher Weight Gains in the Most Malnourished Children

PubMed Central

Dale, Nancy M.; Myatt, Mark; Prudhon, Claudine; Briend, André

2013-01-01

Objective The World Health Organization recommends discharging children admitted to nutrition programs treating severe acute malnutrition, with a low mid-upper arm circumference (MUAC <115 mm) when weight gain is >15%. When this recommendation is followed, the most severely malnourished children receive a shorter treatment compared to children that are less severely malnourished. This study assesses whether using MUAC >125 mm as discharge criteria eliminates this effect. Methods and Findings Data from 753 children cured from a Médecins Sans Frontières outpatient nutrition program in Gedaref, North Sudan were analyzed. MUAC >125 mm was used as discharge criteria. Length of stay and percent weight gain of children were compared in relation to nutritional status on admission. Children with low MUAC on admission had a longer duration of treatment (p = 0.000) and also a higher percent weight gain (p = 0.000) than children with higher MUAC. Similar results with weight-for-height z-scores categories were shown with both duration of treatment (p = 0.000) and percent weight gain (p = 0.000). Conclusion This study shows that using MUAC as the discharge criteria eliminates the effect of shorter treatment in most severely malnourished children compared to least severely malnourished, as is observed with percent weight gain. The findings directly address the main concern that has been identified with the current WHO recommendation of using percent weight gain. MUAC could be used as discharge criteria, instead of percent weight gain, as having a longer duration of treatment and a higher percent weight gain for the most malnourished is highly desirable. PMID:23418442

Pharmacokinetics of Chlorin e6-Cobalt Bis(Dicarbollide) Conjugate in Balb/c Mice with Engrafted Carcinoma

PubMed Central

Volovetsky, Arthur B.; Balalaeva, Irina V.; Dudenkova, Varvara V.; Shilyagina, Natalia Yu.; Feofanov, Аlexey V.; Efremenko, Anastasija V.; Grin, Mikhail A.; Mironov, Andrey F.; Bregadze, Vladimir I.; Maslennikova, Anna V.

2017-01-01

The necessary precondition for efficient boron neutron capture therapy (BNCT) is control over the content of isotope 10B in the tumor and normal tissues. In the case of boron-containing porphyrins, the fluorescent part of molecule can be used for quantitative assessment of the boron content. Study Objective: We performed a study of the biodistribution of the chlorin e6-Cobalt bis(dicarbollide) conjugate in carcinoma-bearing Balb/c mice using ex vivo fluorescence imaging, and developed a mathematical model describing boron accumulation and release based on the obtained experimental data. Materials and Methods: The study was performed on Balb/c tumor-bearing mice (CT-26 tumor model). A solution of the chlorin e6-Cobalt bis(dicarbollide) conjugate (CCDC) was injected into the blood at a dose of 10 mg/kg of the animal’s weight. Analysis of the fluorescence signal intensity was performed at several time points by spectrofluorimetry in blood and by laser scanning microscopy in muscle, liver, and tumor tissues. The boron content in the same samples was determined by mass spectroscopy with inductively coupled plasma. Results: Analysis of a linear approximation between the fluorescence intensity and boron content in the tissues demonstrated a satisfactory value of approximation reliability with a Spearman’s rank correlation coefficient of r = 0.938, p < 0.01. The dynamics of the boron concentration change in various organs, calculated on the basis of the fluorescence intensity, enabled the development of a model describing the accumulation of the studied compound and its distribution in tissues. The obtained results reveal a high level of correspondence between the model and experimental data. PMID:29182594

Pharmacokinetics of Chlorin e₆-Cobalt Bis(Dicarbollide) Conjugate in Balb/c Mice with Engrafted Carcinoma.

PubMed

Volovetsky, Arthur B; Sukhov, Vladimir S; Balalaeva, Irina V; Dudenkova, Varvara V; Shilyagina, Natalia Yu; Feofanov, Аlexey V; Efremenko, Anastasija V; Grin, Mikhail A; Mironov, Andrey F; Sivaev, Igor B; Bregadze, Vladimir I; Maslennikova, Anna V

2017-11-28

The necessary precondition for efficient boron neutron capture therapy (BNCT) is control over the content of isotope 10 B in the tumor and normal tissues. In the case of boron-containing porphyrins, the fluorescent part of molecule can be used for quantitative assessment of the boron content. Study Objective: We performed a study of the biodistribution of the chlorin e ₆-Cobalt bis(dicarbollide) conjugate in carcinoma-bearing Balb/c mice using ex vivo fluorescence imaging, and developed a mathematical model describing boron accumulation and release based on the obtained experimental data. Materials and Methods: The study was performed on Balb/c tumor-bearing mice (CT-26 tumor model). A solution of the chlorin e ₆-Cobalt bis(dicarbollide) conjugate (CCDC) was injected into the blood at a dose of 10 mg/kg of the animal's weight. Analysis of the fluorescence signal intensity was performed at several time points by spectrofluorimetry in blood and by laser scanning microscopy in muscle, liver, and tumor tissues. The boron content in the same samples was determined by mass spectroscopy with inductively coupled plasma. Results: Analysis of a linear approximation between the fluorescence intensity and boron content in the tissues demonstrated a satisfactory value of approximation reliability with a Spearman's rank correlation coefficient of r = 0.938, p < 0.01. The dynamics of the boron concentration change in various organs, calculated on the basis of the fluorescence intensity, enabled the development of a model describing the accumulation of the studied compound and its distribution in tissues. The obtained results reveal a high level of correspondence between the model and experimental data.

46 CFR 71.25-20 - Fire-detecting and extinguishing equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... weight loss exceed 10 percent of weight of charge. Inspect hose and nozzle to be sure they are clear.1... cylinders. Recharge if weight loss exceeds 10 percent of weight of charge.1 1 Cylinders must be tested and...

Changes in boron fiber strength due to surface removal by chemical etching

NASA Technical Reports Server (NTRS)

Smith, R. J.

1976-01-01

The effects of chemical etching on the tensile strength of commercial boron/tungsten fibers were investigated. Fibers with as-received diameters of 203, 143, and 100 micrometers were etched to diameters as small as 43 micrometers. The etching generally resulted in increasing fiber tensile strength with decreasing fiber diameter. And for the 203 micrometer fibers there was an accompanying significant decrease in the coefficient of variation of the tensile strength for diameters down to 89 micrometers. Heat treating these fibers above 1,173 K in a vacuum caused a marked decrease in the average tensile strength of at least 80 percent. But after the fibers were etched, their strengths exceeded the as-received strengths. The tensile strength behavior is explained in terms of etching effects on surface flaws and the residual stress pattern of the as-received fibers.

Perceptions of body image among Malaysian male and female adolescents.

PubMed

Khor, G L; Zalilah, M S; Phan, Y Y; Ang, M; Maznah, B; Norimah, A K

2009-03-01

Body image concerns are common among adolescents as they undergo rapid physical growth and body shape changes. Having a distorted body image is a risk factor for the development of disordered eating behaviours and eating disorders. This study was undertaken to investigate body image concerns among Malaysian male and female adolescents aged 11-15 years. A total of 2,050 adolescents (1,043 males and 1,007 females) with a mean age of 13.1 +/- 0.8 years from secondary schools in Kedah and Pulau Pinang were included in the study. Questionnaires were used to collect socioeconomic data and body image indicators. The majority (87 percent) of the adolescents were concerned with their body shape. While the majority of underweight, normal weight and overweight male and female subjects perceived their body weight status correctly according to their body mass index (BMI), a noteworthy proportion in each category misjudged their body weight. About 35.4 percent of the males and 20.5 percent of the females in the underweight category perceived themselves as having a normal weight, while 29.4 percent and 26.7 percent of the overweight males and females respectively also perceived that they had a normal weight. A higher proportion of the females (20 percent) than males (9 percent) with a normal BMI perceived themselves as fat. Most of the male (78-83 percent) and female subjects (69-74 percent) in all the BMI categories desired to be taller than their current height. An appreciable proportion of both the males (41.9 percent) and females (38.2 percent) preferred to remain thin, or even to be thinner (23.7 percent of males and 5.9 percent of females). Females had a significantly higher mean body dissatisfaction score than males, indicating their preference for a slimmer body shape. More males (49.1 percent) preferred a larger body size while more females (58.3 percent) idealised a smaller body size. Compared to normal weight and underweight subjects, overweight males and females expressed lower confidence and acceptance levels, as well as expressed greater preoccupation with and anxiety over their body weight and shape. As having a distorted body image may lead to negative effects such as unhealthy eating habits and disordered eating behaviours, it is recommended that appropriate educational efforts on body image be incorporated into school health activities for adolescents.

High capacity carbon dioxide sorbent

DOEpatents

Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

2015-09-01

The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

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

Chakravarti, D.; Eisler, R.

The values for strontium-90 and gross beta activity in the fat and non- fat fractions from the livers of twelve coconut crabs (Birgus latro) collected at Rongelap Atoll during March 1958 are presented. Although fat constituted an average of 47 percent by weight on a wet weight basis (74 percent on a dry weight basis), gross beta activity of the fat fraction amounted to less than 0.5 percent of the total activity on a wet weight basis. Fat content on a wet weight basis had a range of 31 percent to 65 percent. There is a linear relationship between strontium-90more » activity and gross beta activity. Since the fat content of coconut crab liver is variable and the fat fraction contains practically no radioactivity, it is suggested that the radioactivity (and mineral content) of liver samples be compared on the basis of the non-fat solids. (auth)« less

Shock compression behavior of a mixture of cubic and hexagonal boron nitride

NASA Astrophysics Data System (ADS)

Hu, Xiaojun; Yang, Gang; Zhao, Bin; Li, Peiyun; Yang, Jun; Leng, Chunwei; Liu, Hanyu; Huang, Haijun; Fei, Yingwei

2018-05-01

We report Hugoniot measurements on a mixture of cubic boron nitride (cBN) and hexagonal boron nitride (hBN, ˜10% in weight) to investigate the shock compression behavior of BN at Hugoniot stresses up to 110 GPa. We observed a discontinuity at ˜77 GPa along the Hugoniot and interpreted it as the manifestation of the shock-induced phase transition of hBN to cBN. The experimental stress at 77-110 GPa shows significant deviation from the hydrodynamic Hugoniot of cBN calculated using the Mie-Grüneisen model coupled with the reported 300 K-isotherms of cBN. Our investigation reveals that material strength in cBN increases with the experimental stress at least up to 110 GPa. The material strength might be preserved at higher stress if we consider the previously reported high stress data.

A comparison of methods for organ-weight data adjustment in chicks.

PubMed

Brown, D R; Southern, L L; Baker, D H

1985-02-01

An experiment was conducted with 168 Arbor Acre X Peterson unsexed, crossbred broiler chicks to compare methods of expressing organ-weight data and to assess changes in organ weights and physiological parameters as body weight (97 to 791 g) and age (5 to 26 days) increased. Actual wet weight of liver, heart, intestine, spleen, and pancreas and percent bone ash increased (P less than .01) as age and body weight increased. Tibia length-to-width ratio decreased (P less than .01) as age and body weight increased. Blood hemoglobin, hematocrit, and plasma protein were not affected (P greater than .1) by age or by body weight. Liver, heart, and intestinal weight decreased (P less than .01) and spleen weight increased (P less than .01) as body weight and age increased when these tissue weights were expressed as percent of body weight. Liver weight adjusted for body weight by covariance analysis, however, remained constant; adjusted heart and intestinal weights decreased (P less than .01), and adjusted spleen weights increased (P less than .01) with increasing age and body weight. The covariate, body weight, was not significant (P greater than .1) for pancreas weight, tibia length-to-width ratio, and percent bone ash. Except for spleen, adjustment by covariance analysis more effectively reduced variation due to body weight than did expression as percent of body weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Water-quality effects and characterization of indicators of onsite wastewater disposal systems in the east-central Black Hills area, South Dakota, 2006-08

USGS Publications Warehouse

Putnam, Larry D.; Hoogestraat, Galen K.; Sawyer, J. Foster

2008-01-01

Onsite wastewater disposal systems (OWDS) are used extensively in the Black Hills of South Dakota where many of the watersheds and aquifers are characterized by fractured or solution-enhanced bedrock with thin soil cover. A study was conducted during 2006-08 to characterize water-quality effects and indicators of OWDS. Water samples were collected and analyzed for potential indicators of OWDS, including chloride, bromide, boron, nitrite plus nitrate (NO2+NO3), ammonia, major ions, nutrients, selected trace elements, isotopes of nitrate, microbiological indicators, and organic wastewater compounds (OWCs). The microbiological indicators were fecal coliforms, Escherichia coli (E. coli), enterococci, Clostridium perfringens (C. perfringens), and coliphages. Sixty ground-water sampling sites were located either downgradient from areas of dense OWDS or in background areas and included 25 monitoring wells, 34 private wells, and 1 spring. Nine surface-water sampling sites were located on selected streams and tributaries either downstream or upstream from residential development within the Precambrian setting. Sampling results were grouped by their hydrogeologic setting: alluvial, Spearfish, Minnekahta, and Precambrian. Mean downgradient dissolved NO2+NO3 concentrations in ground water for the alluvial, Spearfish, Minnekahta, and Precambrian settings were 0.734, 7.90, 8.62, and 2.25 milligrams per liter (mg/L), respectively. Mean downgradient dissolved chloride concentrations in ground water for these settings were 324, 89.6, 498, and 33.2 mg/L, respectively. Mean downgradient dissolved boron concentrations in ground water for these settings were 736, 53, 64, and 43 micrograms per liter (ug/L), respectively. Mean dissolved surface-water concentrations for NO2+NO3, chloride, and boron for downstream sites were 0.222 mg/L, 32.1 mg/L, and 28 ug/L, respectively. Mean values of delta-15N and delta-18O (isotope ratios of 14N to 15N and 18O to 16O relative to standard ratios) for nitrate in ground-water samples were 10.4 and -2.0 per mil (0/100), respectively, indicating a relatively small contribution from synthetic fertilizer and probably a substantial contribution from OWDS. The surface-water sample with the highest dissolved NO2+NO3 concentration of 1.6 mg/L had a delta-15N value of 12.36 0/100, which indicates warm-blooded animals (including humans) as the nitrate source. Fecal coliforms were detected in downgradient ground water most frequently in the Spearfish (19 percent) and Minnekahta (9.7 percent) settings. E. coli was detected most frequently in the Minnekahta (29 percent) and Spearfish (13 percent) settings. Enterococci were detected more frequently than other microbiological indicators in all four settings. Fecal coliforms and E. coli were detected in 73 percent and 95 percent of all surface-water samples, respectively. Enterococci, coliphages (somatic), and C. perfringens were detected in 50, 70, and 50 percent of surface-water samples, respectively. Of the 62 OWC analytes, 12 were detected only in environmental samples, 10 were detected in at least one environmental and one blank sample (not necessarily companion pairs), 2 were detected only in blank samples, and 38 were not detected in any blank, environmental, or replicate sample from either ground or surface water. Eleven different organic compounds were detected in ground-water samples at eight different sites. The most frequently occurring compound was DEET, which was found in 32 percent of the environmental samples, followed by tetrachloroethene, which was detected in 20 percent of the samples. For surface-water samples, 16 organic compounds were detected in 9 of the 10 total samples. The compound with the highest occurrence in surface-water samples was camphor, which was detected in 50 percent of samples. The alluvial setting was characterized by relatively low dissolved NO2+NO3 concentrations, detection of ammonia nitrogen, and relatively high concentr

75 FR 5947 - Stainless Steel Sheet and Strip in Coils from Taiwan: Final Results and Rescission in Part of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-05

... also contains, by weight, phosphorus of 0.025 percent or less, silicon of between 0.20 and 0.50 percent..., chromium of between 19 and 22 percent, aluminum of no less than 5.0 percent, phosphorus of no more than 0..., silicon and molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur each...

From oligomers to molecular giants of soybean oil in supercritical carbon dioxide medium: 1. Preparation of polymers with lower molecular weight from soybean oil.

PubMed

Liu, Zengshe; Sharma, Brajendra K; Erhan, Sevim Z

2007-01-01

Polymers with a low molecular weight derived from soybean oil have been prepared in a supercritical carbon dioxide medium by cationic polymerization. Boron trifluoride diethyl etherate was used as an initiator. Influences of polymerization temperature, amount of initiator, and carbon dioxide pressure on the molecular weight were investigated. It is shown that the higher polymerization temperature favors polymers with relatively higher molecular weights. Larger amounts of initiator also provide polymers with higher molecular weights. Higher pressure favors polymers with relatively higher molecular weights. The applications of these soy-based materials will be in the lubrication and hydraulic fluid areas.

Predicting successful long-term weight loss from short-term weight-loss outcomes: new insights from a dynamic energy balance model (the POUNDS Lost study)123

PubMed Central

Ivanescu, Andrada E; Martin, Corby K; Heymsfield, Steven B; Marshall, Kaitlyn; Bodrato, Victoria E; Williamson, Donald A; Anton, Stephen D; Sacks, Frank M; Ryan, Donna; Bray, George A

2015-01-01

Background: Currently, early weight-loss predictions of long-term weight-loss success rely on fixed percent-weight-loss thresholds. Objective: The objective was to develop thresholds during the first 3 mo of intervention that include the influence of age, sex, baseline weight, percent weight loss, and deviations from expected weight to predict whether a participant is likely to lose 5% or more body weight by year 1. Design: Data consisting of month 1, 2, 3, and 12 treatment weights were obtained from the 2-y Preventing Obesity Using Novel Dietary Strategies (POUNDS Lost) intervention. Logistic regression models that included covariates of age, height, sex, baseline weight, target energy intake, percent weight loss, and deviation of actual weight from expected were developed for months 1, 2, and 3 that predicted the probability of losing <5% of body weight in 1 y. Receiver operating characteristic (ROC) curves, area under the curve (AUC), and thresholds were calculated for each model. The AUC statistic quantified the ROC curve’s capacity to classify participants likely to lose <5% of their body weight at the end of 1 y. The models yielding the highest AUC were retained as optimal. For comparison with current practice, ROC curves relying solely on percent weight loss were also calculated. Results: Optimal models for months 1, 2, and 3 yielded ROC curves with AUCs of 0.68 (95% CI: 0.63, 0.74), 0.75 (95% CI: 0.71, 0.81), and 0.79 (95% CI: 0.74, 0.84), respectively. Percent weight loss alone was not better at identifying true positives than random chance (AUC ≤0.50). Conclusions: The newly derived models provide a personalized prediction of long-term success from early weight-loss variables. The predictions improve on existing fixed percent-weight-loss thresholds. Future research is needed to explore model application for informing treatment approaches during early intervention. The POUNDS Lost study was registered at clinicaltrials.gov as NCT00072995. PMID:25733628

Parametric Study of a Mach 2.4 Transport Engine with Supersonic Through-Flow Rotor and Supersonic Counter-Rotating Diffuser (SSTR/SSCRD)

NASA Technical Reports Server (NTRS)

Tran, Donald H.

2004-01-01

A parametric study is conducted to evaluate a mixed-flow turbofan equipped with a supersonic through-flow rotor and a supersonic counter-rotating diffuser (SSTR/SSCRD) for a Mach 2.4 civil transport. Engine cycle, weight, and mission analyses are performed to obtain a minimum takeoff gross weight aircraft. With the presence of SSTR/SSCRD, the inlet can be shortened to provide better pressure recovery. For the same engine airflow, the inlet, nacelle, and pylon weights are estimated to be 73 percent lighter than those of a conventional inlet. The fan weight is 31 percent heavier, but overall the installed engine pod weight is 11 percent lighter than the current high-speed civil transport baseline conventional mixed-flow turbofan. The installed specific fuel consumption of the supersonic fan engine is 2 percent higher than that of the baseline turbofan at supersonic cruise. Finally, the optimum SSTR/SSCRD airplane meets the FAR36 Stage 3 noise limit and is within 7 percent of the baseline turbofan airplane takeoff gross weight over a 5000-n mi mission.

Aqueous flooding methods for tertiary oil recovery

DOEpatents

Peru, Deborah A.

1989-01-01

A method of aqueous flooding of subterranean oil bearing formation for tertiary oil recovery involves injecting through a well into the formation a low alkaline pH aqueous sodium bicarbonate flooding solution. The flooding solution's pH ranges from about 8.25 to 9.25 and comprises from 0.25 to 5 weight percent and preferably about 0.75 to 3.0 weight percent of sodium bicarbonate and includes a petroleum recovery surfactant of 0.05 to 1.0 weight percent and between 1 and 20 weight percent of sodium chloride. After flooding, an oil and water mixture is withdrawn from the well and the oil is separated from the oil and water mixture.

Thermal stability of some aircraft turbine fuels derived from oil shale and coal

NASA Technical Reports Server (NTRS)

Reynolds, T. W.

1977-01-01

Thermal stability breakpoint temperatures are shown for 32 jet fuels prepared from oil shale and coal syncrudes by various degrees of hydrogenation. Low severity hydrotreated shale oils, with nitrogen contents of 0.1 to 0.24 weight percent, had breakpoint temperatures in the 477 to 505 K (400 to 450 F) range. Higher severity treatment, lowering nitrogen levels to 0.008 to 0.017 weight percent, resulted in breakpoint temperatures in the 505 to 533 K (450 to 500 F) range. Coal derived fuels showed generally increasing breakpoint temperatures with increasing weight percent hydrogen, fuels below 13 weight percent hydrogen having breakpoints below 533 K (500 F). Comparisons are shown with similar literature data.

QMD and classical MD simulation of alpha boron and boron-carbide behavior under pressure

NASA Astrophysics Data System (ADS)

Yanilkin, Alexey; Korotaev, Pavel; Kuksin, Alexey; Pokatashkin, Pavel

2015-06-01

Boron and some boron-rich compounds are super-hard and light-weighted material with a wide range of different applications. Nevertheless, the question of its behavior under pressure is still open. In the present work we study the equation of state (EOS), stability and deformation of α-B and B4C under high pressure within quantum and classical molecular dynamics (QMD and MD). Based on QMD results the finite temperature EOSs are revealed. CBC chain bending, amorphization and recrystallization of B4C are investigated under hydrostatic, uniform and uniaxial compression. The influence of nonhydrostatic loading is discussed. Angular dependent interatomic potentials are derived by force-matching method. The properties of α-B and B4C, obtained by classical potential, are verified. Structure, bulk modulus, pressure-volume relation, Gruneisen and thermal expansion coefficients are in good agreement with both ab initio and experimental data. These potentials are used to study shock wave propagation in a single crystal of α-B and B4C. Two mechanisms of shear deformation are observed: stacking fault formation and local amorphization. The crystallographic orientations of defects are in a good agreement with experiments.

76 FR 25668 - Stainless Steel Sheet and Strip in Coils From Mexico: Final Results of the Five-Year (“Sunset...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-05

... between 0.20 and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0.025 percent..., aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent, sulfur of no more than 0.03... or less, with phosphorus and sulfur each comprising, by weight, 0.03 percent or less. This steel has...

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the middle Green River basin, Utah, 1986-87

USGS Publications Warehouse

Stephens, D.W.; Waddell, Bruce; Miller, J.B.

1988-01-01

Reconnaissance of wildlife areas in the middle Green River basin of Utah was conducted during 1986 and 1987 to determine whether irrigation drainage has caused, or has the potential to cause significant harmful effects on human health, fish, and wildlife, or may adversely affect the suitability of water for beneficial uses. Studies at Stewart Lake Waterfowl Management Area and Ouray National Wildlife Refuge indicated that concentrations of boron, selenium, and zinc in water, bottom sediment, and biological tissue were sufficiently large to be harmful to fish and wildlife, and to adversely affect beneficial uses of water. Selenium is the principal element of concern in both areas. Concentrations of dissolved selenium in irrigation drain water entering Stewart Lake Waterfowl Management Area ranged from 14-140 micrograms/L (ug/L) and consistently exceeded Utah standards for wildlife protection in water in two of the four drains. Concentrations of boron and zinc exceeded Utah standards only occasionally in the drain waters. Concentrations of total selenium in sediments collected where the drains discharge into the lake were 10-85 ug/gm. Liver tissue collected from American coots at Stewart Lake Waterfowl Management Area contained concentrations of selenium from 4.9-26 ug/gm (dry weight), and whole body samples of carp contained as much as 31 ug/gm (dry weight). Concentrations of selenium in Potamogeton and blue-green algae ranged from 2.1-27 ug/gm. Concentrations of boron, selenium, and zinc were also measured in water from Ouray National Wildlife Refuge. Liver tissue of American coots from the North Roadside Pond, which receives irrigation tailwater, contained a geometric-mean concentration of selenium of 32 ug/gm (dry weight). Five water-bird eggs collected from the North and South Roadside Ponds contained selenium concentrations of 63-120 ug/gm (dry weight). (Lantz-PTT)

The relationship between biological cognitive and psychosocial characteristics of parents and the weight of infant at the time of birth in Isfahan.

PubMed

Talebian, Mohammad Hassan; Afrooz, Gholam Ali; Hooman, Heidar Ali; Aghaei, Asghar

2013-01-01

The present study was connected in order to evaluate the relationship between biological, cognitive and psychosocial characteristics of mothers and the weight of infant at the time of birth. In order to conduct this research a sample of 910 women among recently delivered mothers of Isfahan province in 2009 were selected. From stratified sampling and cluster sampling according to the percentage of population in each of the cities of Isfahan Province was used. The data was gathered with a questionnaire prepared by the researcher in order to evaluate the biological cognitive and psychosocial characteristics of mothers, in addition to the Enrich marital satisfaction test. After collecting data, the analysis of the data was done with SPSS software in two categories of descriptive and inferential statistics by using logistic regression model. The results showed that the prevalence of low weight infants was 9.5 percent and 38.7 percent of pregnancies was unwanted. Twenty-nine percent of mothers had marital dissatisfaction. 15/6 percent of pregnancies were below 20 years old and 22 percent was above of 35 years old. 38.9 percent of mothers were exposed to cigarette smoke. The average of weight gain during pregnancies was 9 kilograms. Thirty three percent of mothers had high blood pressure during pregnancy, 26.7 percent had history of abortion and 31.9 percent had history of bleeding. 23/1percent of women was employed during pregnancy, 19.8 percent gave twin birth and 21/1 percent of parents were relative of each other, 29.7 percent of deliveries were done in cesarean way. The results of this study showed that severe marital dissatisfaction, abnormal blood pressure during pregnancy, being employed during pregnancy, weight gain less than 5 Kg during pregnancy, pregnancy below the age of 20 can meaning fully increase the possibility of low birth weight in infant (α=0.05). The results were consisting with the previous findings and indicated that some of the applicable benefits of this research can be recording of information about each delivery in the whole country with holding training workshops of before and during pregnancy skills by welfare organization.

Safety, Health and Environmental Hazards Associated with Composites: A Complete Analysis

DTIC Science & Technology

1992-11-01

evolve (Ballinger 2). Likewise, important fiber materials such as glass, carbon/graphite, aramid ( Kevlar ), and boron are prevalent in the industry. Each...absorption. Skin irritation or sensitization may result from extended exposure (Ballinger 2). Polyurethanes and Urea-/ Phenol -formaldehyde - These resin systems...percent scrap in the formation of laminate lay-ups (Lee 24). Because of limited applications, this is regarded as waste. In the future, this level of waste

Photographic Processing Interpretation Facility Wastewater Conceptual Treatment Design.

DTIC Science & Technology

1983-03-01

Total Chromium (Cr) - - - ɘ.05 - Copper (Cu) - - - ɘ.05 - Iron (Fe) - - - - - Manganese (Mn) - - - ɘ.03 - Mercury (Hg) - - - ɘ.004 - Potassium (K...8.3 - Silver (Ag) 2.2 7.0 17 0.15 2.2 Sodium (Na) - - - 8.2 - Zinc (Zn) - - - 0.12 - Biochemical Oxygen " Demand (BOD_) - - - 40 - Sulfate (SO...nonconventional pollutants include boron, dissolved sol i halides, iron, ammonia, nitrogen, phenols, sulfate and TOC. ,P,, 99 percent of the 11,000

Iron Supplements Reduce Behavior Problems in Low Birth Weight Infants

MedlinePlus

... low birth weight groups and the normal-weight control group. However, for behavioral problems, there was a significant ... percent of the 2-mg group. In the control group, 3.2 percent of children showed signs of ...

Evaluation, construction and endurance testing of compression sealed pyrolytic boron nitride slot insulation

NASA Technical Reports Server (NTRS)

Grant, W. L.

1969-01-01

A high-temperature statorette, consisting of an iron-27 percent cobalt magnetic lamination stack and nickel-clad silver conductors, was tested with pyrolytic boron nitride slot insulation. Temperatures were measured in each test to determine characteristics of slot linear heat conductance from statorette conductors. Testing was carried out to temperatures of approximately 1500 F in a vacuum environment of 10-8 torr. Three assemblies were built and tested, each having a different room temperature slot clearance. The final statorette assembly was subjected to a 100-hour vacuum aging test at 1400 F followed by 25 thermal cycles. Temperature data from the three assemblies showed that decreasing slot clearance and increasing compression loading did enhance heat transfer. The temperature difference between slot and lamination at 1400 F increased 4 F during the thermal aging and an additional 10 F during the 25 thermal cycles.

Adaptive Trajectory Prediction Algorithm for Climbing Flights

NASA Technical Reports Server (NTRS)

Schultz, Charles Alexander; Thipphavong, David P.; Erzberger, Heinz

2012-01-01

Aircraft climb trajectories are difficult to predict, and large errors in these predictions reduce the potential operational benefits of some advanced features for NextGen. The algorithm described in this paper improves climb trajectory prediction accuracy by adjusting trajectory predictions based on observed track data. It utilizes rate-of-climb and airspeed measurements derived from position data to dynamically adjust the aircraft weight modeled for trajectory predictions. In simulations with weight uncertainty, the algorithm is able to adapt to within 3 percent of the actual gross weight within two minutes of the initial adaptation. The root-mean-square of altitude errors for five-minute predictions was reduced by 73 percent. Conflict detection performance also improved, with a 15 percent reduction in missed alerts and a 10 percent reduction in false alerts. In a simulation with climb speed capture intent and weight uncertainty, the algorithm improved climb trajectory prediction accuracy by up to 30 percent and conflict detection performance, reducing missed and false alerts by up to 10 percent.

Effects of incandescent radiation on photosynthesis, growth rate and yield of 'Waldmann's Green' leaf lettuce

NASA Technical Reports Server (NTRS)

Knight, Sharon L.; Mitchell, Cary A.

1988-01-01

Effects of different ratios of incandescent (ln) to fluorescent (Fl) radiation were tested on growth of 'Waldmann's Green' leaf lettuce in a controlled environment. After 4 days of treatment, dry weight, leaf area, relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR) and photosynthetic rate (Pn) were greater for plants grown at 84 rather than 16 percent of total irradiance (82 W/sq m) from ln lamps. Although leaf dry weight and area were 12-17 percent greater at 84 percent ln after the first 8 days of treatment, there were no differences in RGR or Pn between treatments during the last 4 days. If 84 percent ln was compared with 50 percent ln, all cumulative growth parameters, RGR, NAR and Pn were greater for 84 percent ln during the first 4 days of treatment. However, during the second 4 days, RGR was greater for the 50 percent ln treatment, resulting in no net difference in leaf dry weight or area between treatments. Shifting from 84 to 50 percent ln radiation between the first and second 4 days of treatment increased plant dry weight, leaf area, RGR and NAR relative to those under 84 percent ln for 8 days continuously.

Colorectal cancer: intrinsic characteristics modulate cancer energy expenditure and the risk of cachexia.

PubMed

Ravasco, Paula; Monteiro-Grillo, Isabel; Camilo, Maria

2007-08-01

To conduct a prospective longitudinal study in colorectal cancer (CRC) patients: 1) to evaluate resting energy expenditure (REE), weight/dietary intake changes, and response to treatment, taking into consideration cancer stage and histology; 2) to determine their potential interrelations; and 3) to quantify the relative contributions to REE of cancer/nutrition/treatment. 101 CRC patients proposed for neoadjuvant radiotherapy (RT) were evaluated before and after RT: REE (indirect calorimetry measurements), percentage of weight loss, usual diet (diet history), current diet (24 hour recall), and treatment response. REE was higher in Stages III/IV versus I/II, at the RT onset (p < 0.002) and end (p = 0.02), and in moderately/poorly/undifferentiated cancers vs well differentiated (onset, p < 0.001) and (RT end, p = 0.01); weight/intake reductions were also greater in Stages III/IV versus I/II (p < 0.01) and in moderately/poorly/undifferentiated cancers versus well differentiated (p < 0.02). According to patients' response to treatment, REE was increased in Stage III/IV (p < 0.005) and Grade 2/3 histology (p < 0.003). In nonresponders, REE increased 7.2 +/- 1.3 kcal/kg/day and decreased 2.8 +/- 0.4 kcal/kg/day in responders. REE changes were not-significantly influenced by weight/intake. Relative contributions to baseline REE were determined in 25 percent by stage, in 25 percent by histology, in 3 percent by intake and in 4 percent by weight loss. At the end of RT, higher REE was attributed in 26 percent to stage, in 27 percent to histology, in 30 percent to nontreatment response, in 9 percent to intake, and in 8 percent to weight loss. In this CRC patient population, higher metabolic rates were mainly determined by the tumor burden and aggressiveness in association with response to treatment clearly disclaiming the effect of weight loss and/or dietary intake reductions.

Surface-Tolerant Coatings for Aircraft Hangars, Flight Control Tower, and Deluge Tanks at Fort Campbell

DTIC Science & Technology

2007-06-01

to chalking. Fluorinated polymers are recognized as the most durable coatings in terms of preservation of appearance. Architectural building panels...phosphate) 19.4 Percent by Weight Film-Former phenolic varnish 55.3 Percent by Weight Antioxidant butylated hydroxytoluene (BHT) 0.43 Percent

Electrolytes for Low Impedance, Wide Operating Temperature Range Lithium-Ion Battery Module

NASA Technical Reports Server (NTRS)

Hallac, Boutros (Inventor); Krause, Frederick C. (Inventor); Jiang, Junwei (Inventor); Smart, Marshall C. (Inventor); Metz, Bernhard M. (Inventor); Bugga, Ratnakumar V. (Inventor)

2018-01-01

A lithium ion battery cell includes a housing, a cathode disposed within the housing, wherein the cathode comprises a cathode active material, an anode disposed within the housing, wherein the anode comprises an anode active material, and an electrolyte disposed within the housing and in contact with the cathode and anode. The electrolyte consists essentially of a solvent mixture, a lithium salt in a concentration ranging from approximately 1.0 molar (M) to approximately 1.6 M, and an additive mixture. The solvent mixture includes a cyclic carbonate, an non-cyclic carbonate, and a linear ester. The additive mixture consists essentially of lithium difluoro(oxalato)borate (LiDFOB) in an amount ranging from approximately 0.5 weight percent to approximately 2.0 weight percent based on the weight of the electrolyte, and vinylene carbonate (VC) in an amount ranging from approximately 0.5 weight percent to approximately 2.0 weight percent based on the weight of the electrolyte.

76 FR 2332 - Stainless Steel Sheet and Strip in Coils From Mexico; Final Results of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-13

... molybdenum, and between 0.20 and 0.80 percent manganese. This steel also contains, by weight, phosphorus of 0..., aluminum of no less than 5.0 percent, phosphorus of no more than 0.045 percent, sulfur of no more than 0.03... molybdenum each comprise, by weight, 0.05 percent or less, with phosphorus and sulfur each comprising, by...

Aboveground Biomass of Choctawhatchee Sand Pine in Northwest Florida

Treesearch

Michael A. Taras

1980-01-01

Choctawhatchee sand pine trees 4 to 14 inches d.b.h. were selected from a natural, uneven-aged stand in northwest Florida to determine the weight and volume of above ground biomass. On the average, 85 percent of the green weight of the total tree was wood, 11 percent bark. and 4 percent needles. The average tree sampled had 82 percent of its wood in the stem and 18...

Triangular osteosynthesis of vertically unstable sacrum fractures: a new concept allowing early weight-bearing.

PubMed

Schildhauer, T A; Josten, Ch; Muhr, G

2006-01-01

Presentation of a new triangular osteosynthesis technique that permits early weight-bearing in vertically unstable sacral fractures. : Retrospective evaluation of a consecutive series. Level I trauma center. Thirty-four patients, twenty-eight of whom were poly-traumatized, all with vertically unstable sacral fractures. This group included eight women and twenty-six men, with a mean age of thirty-five years. Average time between trauma and definite operation was thirteen days (range 0 to 28 days). All patients underwent triangular osteosynthesis using a combination of a vertical vertebro-pelvic distraction osteosynthesis (pedicle screw system) and a transverse fixation of the sacrum fracture with either iliosacral screws or trans-sacral plating. Immediate postoperative weight-bearing was permitted postoperatively. Nineteen patients were treated with early progressive weight-bearing and advanced to full weight-bearing, on average, after twenty-three days (range 8 to 70 days). Three of the thirty-four patients (9 percent) experienced loosening of hardware, including two patients (6 percent) who required secondary intervention because of loss of the original reduction. Further complications included one pulmonary embolism (3 percent), one iatrogenic nerve lesion (3 percent), one wound necrosis (3 percent), and two local infections (6 percent). Triangular osteosynthesis is a demanding procedure that can be performed on vertically unstable sacral fractures to allow early progressive weight-bearing with an acceptable complication rate.

Design and UV-curable behaviour of boron based reactive diluent for epoxy acrylate oligomer used for flame retardant wood coating

PubMed Central

Chambhare, Sachin U.; Lokhande, Gunawant P.; Jagtap, Ramanand N.

2017-01-01

Abstract Difunctional boron-containing reactive flame retardant for UV-curable epoxy acrylate oligomer was synthesized from phenyl boronic acid and glycidyl methacrylate. The synthesized reactive diluent was utilized to formulate ultraviolet (UV)-curable wood coatings. The weight fractions of reactive diluent in coatings formulation was varied from 5 to 25 wt % with constant photoinitiator concentration. The molecular structure of reactive flame retardant was confirmed by Fourier-transform infrared, Nuclear magnetic resonance (NMR) and 11B NMR spectral analysis. Further, the efficacy of flame retardant behaviour of coatings was evaluated using limiting oxygen index and UL-94 vertical burning test. Thermal stability of cured coatings films were estimated from thermogravimetric and differential scanning calorimetry analysis. The effects of varying concentration of reactive diluent on the viscosity of coatings formulation along with optical, mechanical and chemical resistance properties of coatings were also evaluated. The coatings gel content, water absorption behaviour, contact angle analysis and stain resistance were also studied. PMID:29491786

Copper and boron fixation in wood by pyrolytic resins.

PubMed

Mourant, Daniel; Yang, Dian-Qing; Lu, Xiao; Riedl, Bernard; Roy, Christian

2009-02-01

A phenol-formaldehyde (PF)-resin designed to penetrate wood and immobilize copper and boron in wood cells for protection against decay was investigated. The phenol portion of the PF-resin was partially substituted with pyrolysis oil derived from softwood bark. The objective was to reduce the environmental impact associated with the production of petroleum-borne phenol, as well as to improve the product economics. Leaching tests were conducted with three different formulas of resins containing 50%, 75% or 85% by weight of pyrolytic oil on a total phenol basis. The leachates were analyzed for the presence of copper by atomic absorption spectroscopy while inductively coupled plasma spectroscopy was used for boron detection. Copper leaching was reduced up to 18 times when comparing the treatments with and without the resin. Preservative leaching varied between wood species as well as between the resins containing different concentrations of pyrolytic oil. The organic leachates were measured using gas chromatography and mass spectroscopy. Trace amounts of organics, mostly acetic acid, were found in the leachates.

Analytical and experimental investigation of aircraft metal structures reinforced with filamentary composites. Phase 1: Concept development and feasibility

NASA Technical Reports Server (NTRS)

Oken, S.; June, R. R.

1971-01-01

The analytical and experimental investigations are described in the first phase of a program to establish the feasibility of reinforcing metal aircraft structures with advanced filamentary composites. The interactions resulting from combining the two types of materials into single assemblies as well as their ability to function structurally were studied. The combinations studied were boron-epoxy reinforced aluminum, boron-epoxy reinforced titanium, and boron-polyimide reinforced titanium. The concepts used unidirectional composites as reinforcement in the primary loading direction and metal for carrying the transverse loads as well as its portion of the primary load. The program established that several realistic concepts could be fabricated, that these concepts could perform to a level that would result in significant weight savings, and that there are means for predicting their capability within a reasonable degree of accuracy. This program also encountered problems related to the application of polyimide systems that resulted in their relatively poor and variable performance.

Hollow microspheres of silica glass and method of manufacture

DOEpatents

Downs, Raymond L.; Miller, Wayne J.

1982-01-01

A method of manufacturing gel powder suitable for use as a starting material in the manufacture of hollow glass microspheres having a high concentration of silica. The powder is manufactured from a gel containing boron in the amount of about 1% to 20% (oxide equivalent mole percent), alkali metals, specifically potassium and sodium, in an amount exceeding 8% total, and the remainder silicon. Preferably, the ratio of potassium to sodium is greater than 1.5.

Corrosion resistant iron aluminides exhibiting improved mechanical properties and corrosion resistance

DOEpatents

Liu, C.T.; McKamey, C.G.; Tortorelli, P.F.; David, S.A.

1994-06-14

The specification discloses a corrosion-resistant intermetallic alloy comprising, in atomic percent, an FeAl iron aluminide containing from about 30 to about 40% aluminum alloyed with from about 0.01 to 0.4% zirconium and from 0.01 to about 0.8% boron. The alloy exhibits considerably improved room temperature ductility for enhanced usefulness in structural applications. The high temperature strength and fabricability is improved by alloying with molybdenum, carbon, chromium and vanadium. 9 figs.

Corrosion resistant iron aluminides exhibiting improved mechanical properties and corrosion resistance

DOEpatents

Liu, Chain T.; McKamey, Claudette G.; Tortorelli, Peter F.; David, Stan A.

1994-01-01

The specification discloses a corrosion-resistant intermetallic alloy comprising, in atomic percent, an FeAl iron aluminide containing from about 30 to about 40% aluminum alloyed with from about 0.01 to 0.4% zirconium and from 0.01 to about 0.8% boron. The alloy exhibits considerably improved room temperature ductility for enhanced usefulness in structural applications. The high temperature strength and fabricability is improved by alloying with molybdenum, carbon, chromium and vanadium.

Dynamic properties of porous B sub 4 C. Interim report

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

Brar, N.S.; Rosenberg, Z.; Bless, S.J.

1990-01-25

The sound speed in porous B4C (Boron Carbide) was measured and predicted on the basis of a spherical void model and a penny crack model. Neither model does well for porosity exceeding 10 percent. Measured values of Hugoniot elastic limit for porous B4C agree well with those predicted by the Steinberg's model. Measured transverse stress in the elastic range of B4C under 1-d strain condition agrees with the predictions.

Coaxial microwave electrothermal thruster performance in hydrogen

NASA Technical Reports Server (NTRS)

Richardson, W.; Asmussen, J.; Hawley, M.

1994-01-01

The microwave electro thermal thruster (MET) is an electric propulsion concept that offers the promise of high performance combined with a long lifetime. A unique feature of this electric propulsion concept is its ability to create a microwave plasma discharge separated or floating away from any electrodes or enclosing walls. This allows propellant temperatures that are higher than those in resistojets and reduces electrode and wall erosion. It has been demonstrated that microwave energy is coupled into discharges very efficiently at high input power levels. As a result of these advantages, the MET concept has been identified as a future high power electric propulsion possibility. Recently, two additional improvements have been made to the coaxial MET. The first was concerned with improving the microwave matching. Previous experiments were conducted with 10-30 percent reflected power when incident power was in excess of 600 W(exp 6). Power was reflected back to the generator because the impedance of the MET did not match the 50 ohm impedance of the microwave circuit. To solve this problem, a double stub tuning system has been inserted between the MET and the microwave power supply. The addition of the double stub tuners reduces the reflected power below 1 percent. The other improvement has prepared the coaxial MET for hydrogen experiments. To operate with hydrogen, the vacuum window which separates the coaxial line from the discharge chamber has been changed from teflon to boron nitride. All the microwave energy delivered to the plasma discharge passes through this vacuum window. This material change had caused problems in the past because of the increased microwave reflection coefficients associated with the electrical properties of boron nitride. However, by making the boron nitride window electrically one-half of a wavelength long, power reflection in the window has been eliminated. This technical note summarizes the experimental performance of the improved coaxial MET when operating in nitrogen, helium, and hydrogen gases.

21 CFR 172.841 - Polydextrose.

Code of Federal Regulations, 2013 CFR

2013-04-01

... consists either of approximately 89 percent D-glucose, 10 percent sorbitol, and 1 percent citric acid or of approximately 90 percent D-glucose, 10 percent sorbitol, and 0.1 percent phosphoric acid, on a weight basis. (2...

21 CFR 172.841 - Polydextrose.

Code of Federal Regulations, 2011 CFR

2011-04-01

... consists either of approximately 89 percent D-glucose, 10 percent sorbitol, and 1 percent citric acid or of approximately 90 percent D-glucose, 10 percent sorbitol, and 0.1 percent phosphoric acid, on a weight basis. (2...

21 CFR 172.841 - Polydextrose.

Code of Federal Regulations, 2012 CFR

2012-04-01

... consists either of approximately 89 percent D-glucose, 10 percent sorbitol, and 1 percent citric acid or of approximately 90 percent D-glucose, 10 percent sorbitol, and 0.1 percent phosphoric acid, on a weight basis. (2...

21 CFR 172.841 - Polydextrose.

Code of Federal Regulations, 2010 CFR

2010-04-01

... consists either of approximately 89 percent D-glucose, 10 percent sorbitol, and 1 percent citric acid or of approximately 90 percent D-glucose, 10 percent sorbitol, and 0.1 percent phosphoric acid, on a weight basis. (2...

40 CFR 98.63 - Calculating GHG emissions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... emissions from anode consumption during electrolysis and anode baking of prebake cells using either the.../metric tons Al). MP = Annual metal production (metric tons Al). Sa = Sulfur content in baked anode (percent weight). Asha = Ash content in baked anode (percent weight). 44/12 = Ratio of molecular weights...

40 CFR 98.63 - Calculating GHG emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... emissions from anode consumption during electrolysis and anode baking of prebake cells using either the.../metric tons Al). MP = Annual metal production (metric tons Al). Sa = Sulfur content in baked anode (percent weight). Asha = Ash content in baked anode (percent weight). 44/12 = Ratio of molecular weights...

40 CFR 98.63 - Calculating GHG emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... emissions from anode consumption during electrolysis and anode baking of prebake cells using either the.../metric tons Al). MP = Annual metal production (metric tons Al). Sa = Sulfur content in baked anode (percent weight). Asha = Ash content in baked anode (percent weight). 44/12 = Ratio of molecular weights...

40 CFR 98.63 - Calculating GHG emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... emissions from anode consumption during electrolysis and anode baking of prebake cells using either the.../metric tons Al). MP = Annual metal production (metric tons Al). Sa = Sulfur content in baked anode (percent weight). Asha = Ash content in baked anode (percent weight). 44/12 = Ratio of molecular weights...

Long-term thermal degradation and alloying constituent effects on five boron/aluminum composites

NASA Technical Reports Server (NTRS)

Olsen, G. C.

1982-01-01

Thermal exposure effects on the properties of five boron/aluminum composite systems were experimentally investigated. The composite systems were 49 volume percent boron fibers (203 micron diameter) in aluminum-alloy matrices 1100 Al, 2024 Al, 3003 Al, 5052 Al, and 6061 Al. Specimens were thermally exposed up to 10,000 hours at 500 K and 590 K, up to 500 hours at 730 K, and up to 10,000 hours at 500 K and 590 K, up to 500 hours at 730 K, and up to 2000 thermal cycles between 200 K and 590 K. Composite longitudinal and transverse tensile strengths, longitudinal compression strength, and in-plane shear strength were determined. None of the systems was severely degraded by exposure at 590 K. The best performing system was B-2024 Al. Effects of matrix alloys on degradation mechanisms were experimentally investigated. Composite specimens and individual fibers were metallurgically analyzed with a scanning electron microscope and an electron microprobe to determine failure characteristics, chemical element distribution, and reaction layer morphology. Alloying constituents were found to be affect the composite degradation mechanisms as follows: alloys containing iron, but without manganese as a stabilizer, caused increased low-temperature degradation; alloys containing magnesium, iron, or manganese caused increased degradation; and alloys containing copper caused increased fiber strength.

Analytical and experimental investigation of aircraft metal structures reinforced with filamentary composites. Phase 3: Major component development

NASA Technical Reports Server (NTRS)

Bryson, L. L.; Mccarty, J. E.

1973-01-01

Analytical and experimental investigations, performed to establish the feasibility of reinforcing metal aircraft structures with advanced filamentary composites, are reported. Aluminum-boron-epoxy and titanium-boron-epoxy were used in the design and manufacture of three major structural components. The components were representative of subsonic aircraft fuselage and window belt panels and supersonic aircraft compression panels. Both unidirectional and multidirectional reinforcement concepts were employed. Blade penetration, axial compression, and inplane shear tests were conducted. Composite reinforced structural components designed to realistic airframe structural criteria demonstrated the potential for significant weight savings while maintaining strength, stability, and damage containment properties of all metal components designed to meet the same criteria.

21 CFR 173.65 - Divinylbenzene copolymer.

Code of Federal Regulations, 2010 CFR

2010-04-01

... weight-percent ethyl-vinyl-benzene, and no more than 4 weight-percent nonpolymerizable impurities. (b) In... Archives and Records Administration (NARA). For information on the availability of this material at NARA...

40 CFR 98.63 - Calculating GHG emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... baking of prebake cells using either the procedures in paragraph (d) of this section or the procedures in.../metric tons Al). MP = Annual metal production (metric tons Al). Sa = Sulfur content in baked anode (percent weight). Asha = Ash content in baked anode (percent weight). 44/12 = Ratio of molecular weights...

Comparison of two self-directed weight loss interventions: Limited weekly support vs. no outside support.

PubMed

Smith, Bryan K; Van Walleghen, Emily L; Cook-Wiens, Galen; Martin, Rachael N; Curry, Chelsea R; Sullivan, Debra K; Gibson, Cheryl A; Donnelly, Joseph E

2009-08-01

The purpose of this study was to compare the efficacy of two home-based weight loss interventions that differ only in the amount of outside support provided. This was a 12-week, randomized, controlled trial. One group received limited support (LWS, n = 35) via a single 10 min phone call each week while another group received no weekly support (NWS, n = 28). Both the LWS and NWS received pre-packaged meals (PM) and shakes. A third group served as control (CON, n = 30) and received no components of the intervention. Weight loss at 12 weeks was the primary outcome. Diet (PM, shake, and fruit/vegetable (F/V) intake) and physical activity (PA) were self-monitored, recorded daily and reported weekly. An exit survey was completed by participants in the intervention groups upon completion of the study. Weight loss and percent weight loss in the LWS, NWS, and CON groups were 7.7 ± 4.4 kg (8.5 ± 4.2%), 5.9 ± 4.1 kg (6.0 ± 4.2%), and 0.3 ± 1.9 kg (0.4 ± 1.2%), respectively. The decrease in body weight and percent weight loss was significantly greater in the LWS and NWS groups when compared to the CON group and the percent weight loss was significantly greater in the LWS when compared to both the NWS and CON groups. A home-based weight loss program utilizing PM and shakes results in clinically significant percent weight loss and the addition of a brief weekly call promotes additional percent weight loss. © 2009 Asian Oceanian Association for the Study of Obesity . Published by Elsevier Ltd. All rights reserved.

Descriptive and grade-tonnage models of volcanogenic manganese deposits in oceanic environments; a modification

USGS Publications Warehouse

Mosier, Dan L.; Page, Norman J

1988-01-01

Four types of volcanogenic manganese deposits, distinguished on the basis of geologic, geochemical, and geophysical characteristics, appear to result from a combination of volcanic and hydrothermal processes related to hot-spring activity in oceanic environments. We compare these four desposit types, here called the Franciscan, Cuban, Olympic Peninsula, and Cyprus, with respect to host rocks, associated rocks, minerals, deposit shape, dimensions, volume, tonnage, grade, and mineral-deposit density (number of deposits per unit area). Franciscan-type deposits occur in obducted oceanic ridge and backarc marginal-basin environments, are associated with chert, shale, and graywacke aroun the margins of mafic volcanic centers, and have a median tonnage of 450 t and median grades of 36 weight percent Mn and less than 5.1 weight percent Fe. Cuban-type deposits occur in island-arc environments, are associated with tuff and limestone around domal structures or intrusions inferred to be volcanic centers, and have a median tonnage of 6,400 t and median grades of 39 weight percent Mn and less than 4.4 weight percent Fe. Olympic Peninsula-type deposits occur in obducted oceanic midplate settings, are associated with argillaceous limestone, argillite, and graywacke around mafic volcanic centers (seamounts or islands), and have a median tonnage of 340 t and median grades of 35 weight percent Mn and less than 6.5 weight percent Fe. Cyprus-type deposits occur in the same tectonic environments as Franciscan type but are associated with basalt, marl, chalk, silt, and chert off the ridge-axis position and have a median tonnage of 41,000 t and median grades of 33 weight percent Fe and 8 weight percent Mn. All these deposits are thin ellipsoids, concordant to the host rocks, but Cyprus-and Cuban-type deposits are larger than Franciscan- and Olympic Peninsula-type deposits. Except for Cyprus-type deposits, which are manganiferous iron (umber) deposits composed of hydrated iron and manganese oxides, all volcanogenic manganese deposits contain manganese oxides, silicates, and carbonates. Mineral-deposit densities, along with grade and tonnage information, are useful for estimating the number, size, andgrades of these deposits in resource assessments.

21 CFR 172.841 - Polydextrose.

Code of Federal Regulations, 2014 CFR

2014-04-01

...-glucose, 10 percent sorbitol, and 1 percent citric acid or of approximately 90 percent D-glucose, 10 percent sorbitol, and 0.1 percent phosphoric acid, on a weight basis. (2) Polydextrose may be partially...

Liposuction of the arm concurrent with brachioplasty in the massive weight loss patient: is it safe?

PubMed

Bossert, Ronald P; Dreifuss, Stephanie; Coon, Devin; Wollstein, Adi; Clavijo-Alvarez, Julio; Gusenoff, Jeffrey A; Rubin, J Peter

2013-02-01

Brachioplasty continues to be a sought-after procedure among the massive weight loss population. Residual adiposity of the upper arm can make this procedure more difficult. The authors sought to determine the safety of arm liposuction outside the region of excision with concomitant excisional brachioplasty. Data were analyzed from a prospective registry of massive weight loss patients who underwent brachioplasty alone or with concurrent arm liposuction. Variables examined included age, sex, body mass index, method of weight loss, medical comorbidities, and smoking status. Outcomes included complications such as seroma, wound dehiscence, infection, hematoma, lymphedema, and need for revision. Multivariate analyses were performed to assess outcome measures. One hundred forty-four patients (139 women and five men; mean body mass index, 29.6 ± 4.1 kg/m; mean age, 46 ± 10.7 years) underwent brachioplasty. Sixty-four patients had concomitant arm liposuction at the time of brachioplasty. The remaining 80 patients underwent excisional brachioplasty alone. Despite significantly higher operative body mass indices among those undergoing concurrent liposuction, no significant differences in complication rates were seen between the liposuction and excision-alone cohorts for seroma (19.1 percent versus 23.1 percent), wound dehiscence (7.9 percent versus 2.6 percent), infection (4.8 percent versus 6.4 percent), hematoma (3.2 percent versus 0 percent), or lymphedema (3.2 percent versus 1.3 percent). Revision rates were similar between the two groups (9.5 percent with liposuction and 8.9 percent without liposuction). Liposuction can be performed safely and effectively outside the region of excision at the time of brachioplasty without the need for prior debulking or staged arm-contouring procedures. Therapeutic, III.

A New Approach to Prepare Vegetable Oil-Based Polymers

USDA-ARS?s Scientific Manuscript database

Polymers from vegetable oils, such as soybean oil, were prepared by cationic polymerization in supercritical carbon dioxide (scCO2) medium. Boron trifluoride diethyl etherate (BF3.OEt2) was selected as catalyst. The resulting polymers have molecular weight ranging from 21,842 to 118,300 g/mol. Nu...

Associations among eating regulation and body mass index, weight, and body fat in college students: the moderating role of gender.

PubMed

Gropper, Sareen S; Arsiwalla, Dilbur D; Lord, Denali C; Huggins, Kevin W; Simmons, Karla P; Ulrich, Pamela V

2014-04-01

This study investigated associations between eating regulation behaviors and body mass index (BMI), weight, and percent body fat in male and female students over the first two years of college. Subjects included 328 college students (215 females and 113 males). Height and weight (via standard techniques), body composition (via bioelectrical impedance analysis), and eating regulation behaviors (using the Regulation of Eating Behavior Scale) were conducted two to three times during both the freshman and sophomore years. Significant associations between eating regulation and BMI, weight, and/or percent body fat were shown mostly in females. In females, higher BMI, weight, and/or percent body fat at the end of the second year of college were found in those with low levels of autonomous, intrinsic motivation, and identified regulation, and high levels of amotivation, while lower BMI, weight, and/or percent body fat were associated with high levels of autonomous, intrinsic motivation, and identified regulation, and low levels of amotivation. The findings that specific eating behaviors in females during the first two years of college influence BMI, weight, and/or percent body fat may be useful for inclusion in university programs focused on college student health to help decrease the risk of obesity and disordered eating/eating disorders in female college students. Copyright © 2014 Elsevier Ltd. All rights reserved.

FE Simulation Models for Hot Stamping an Automobile Component with Tailor-Welded High-Strength Steels

NASA Astrophysics Data System (ADS)

Tang, Bingtao; Wang, Qiaoling; Wei, Zhaohui; Meng, Xianju; Yuan, Zhengjun

2016-05-01

Ultra-high-strength in sheet metal parts can be achieved with hot stamping process. To improve the crash performance and save vehicle weight, it is necessary to produce components with tailored properties. The use of tailor-welded high-strength steel is a relatively new hot stamping process for saving weight and obtaining desired local stiffness and crash performance. The simulation of hot stamping boron steel, especially tailor-welded blanks (TWBs) stamping, is more complex and challenging. Information about thermal/mechanical properties of tools and sheet materials, heat transfer, and friction between the deforming material and the tools is required in detail. In this study, the boron-manganese steel B1500HS and high-strength low-alloy steel B340LA are tailor welded and hot stamped. In order to precisely simulate the hot stamping process, modeling and simulation of hot stamping tailor-welded high-strength steels, including phase transformation modeling, thermal modeling, and thermal-mechanical modeling, is investigated. Meanwhile, the welding zone of tailor-welded blanks should be sufficiently accurate to describe thermal, mechanical, and metallurgical parameters. FE simulation model using TWBs with the thickness combination of 1.6 mm boron steel and 1.2 mm low-alloy steel is established. In order to evaluate the mechanical properties of the hot stamped automotive component (mini b-pillar), hardness and microstructure at each region are investigated. The comparisons between simulated results and experimental observations show the reliability of thermo-mechanical and metallurgical modeling strategies of TWBs hot stamping process.

Better load-weight distribution is needed for tandem-axle logging trucks

Treesearch

John E. Baumgras

1976-01-01

To determine the GVW and axle weights of tandem-axle logging trucks hauling into two West Virginia sawmills, 543 truckloads of hardwood sawlogs were weighed. The results showed that less than 2 percent of the truckloads exceeded the 48,000 pound GVW limit. While 58 percent of the truckloads exceeded the 32,000 pound tandem-axle weight limit, the front-axle weights...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2012 CFR

2012-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2014 CFR

2014-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

27 CFR 21.63 - Formula No. 36.

Code of Federal Regulations, 2013 CFR

2013-04-01

... pounds of caustic soda, liquid grade, containing 50 percent sodium hydroxide by weight; or 12.0 pounds of caustic soda, liquid grade, containing 73 percent sodium hydroxide by weight. (b) Authorized uses. (1) As...

21 CFR 177.2415 - Poly(aryletherketone) resins.

Code of Federal Regulations, 2014 CFR

2014-04-01

..., and have a minimum weight-average molecular weight of 12,000, as determined by gel permeation...: Distilled water, 50 percent (by volume) ethanol in distilled water, 3 percent acetic acid in distilled water...

Ethanol extraction of phytosterols from corn fiber

DOEpatents

Abbas, Charles; Beery, Kyle E.; Binder, Thomas P.; Rammelsberg, Anne M.

2010-11-16

The present invention provides a process for extracting sterols from a high solids, thermochemically hydrolyzed corn fiber using ethanol as the extractant. The process includes obtaining a corn fiber slurry having a moisture content from about 20 weight percent to about 50 weight percent solids (high solids content), thermochemically processing the corn fiber slurry having high solids content of 20 to 50% to produce a hydrolyzed corn fiber slurry, dewatering the hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, washing the residual corn fiber, dewatering the washed, hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, and extracting the residual corn fiber with ethanol and separating at least one sterol.

Medial thigh lift in the massive weight loss population: outcomes and complications.

PubMed

Gusenoff, Jeffrey A; Coon, Devin; Nayar, Harry; Kling, Russell E; Rubin, J Peter

2015-01-01

Complication profiles of medial thighplasty in the massive weight loss population are not well described. The authors present their experience with these procedures in the massive weight loss population. Thighplasty patients from 2003 to 2012 were assessed. Variables included age, sex, body mass index, method of weight loss, comorbidities, and smoking status. Outcomes included seroma, dehiscence, infection, hematoma, edema, and revision. Statistical analysis was performed as appropriate. One hundred six subjects (90 women and 16 men) underwent thighplasty. Fourteen patients underwent horizontal thighplasty, with a complication rate of 43 percent; 24 underwent short-scar thighplasty, with a complication rate of 67 percent; and 68 underwent full-length vertical thighplasty, with a complication rate of 74 percent. Seventy-two subjects (68 percent) had at least one complication. Complications included dehiscence (51 percent), seroma (25 percent), infection (16 percent), and hematoma (6 percent). Overall, 25 patients (23 percent) developed edema, which did not resolve in two patients by 12 months. Hypertension was significantly associated with postoperative seroma (p = 0.02). Age (p = 0.01), hypothyroidism (p = 0.01), and liposuction outside the area of resection (p = 0.025) were associated with postoperative infections. A full-length vertical incision was associated with increased lower extremity edema (p = 0.007). Medial thighplasty has a high rate of minor wound healing problems. Full-length vertical thighplasty is associated with prolonged edema. Concomitant liposuction may also increase complications. Patients should be counseled appropriately about the potential for minor wound healing problems. Therapeutic, III.

Improved Supercritical-Solvent Extraction of Coal

NASA Technical Reports Server (NTRS)

Compton, L.

1982-01-01

Raw coal upgraded by supercritical-solvent extraction system that uses two materials instead of one. System achieved extraction yields of 20 to 49 weight percent. Single-solvent yields are about 25 weight percent. Experimental results show extraction yields may be timedependent. Observed decreases in weight of coal agreed well with increases in ash content of residue.

40 CFR 63.5830 - What are my options for meeting the standards for pultrusion operations subject to the 60 weight...

Code of Federal Regulations, 2010 CFR

2010-07-01

... standards for pultrusion operations subject to the 60 weight percent organic HAP emissions reductions... National Emissions Standards for Hazardous Air Pollutants: Reinforced Plastic Composites Production Options... operations subject to the 60 weight percent organic HAP emissions reductions requirement? You must use one or...

Problem Video Gaming Among Children Enrolled in Tertiary Weight Management Programs.

PubMed

Stubblefield, Sam; Datto, George; Phan, Thao-Ly T; Werk, Lloyd N; Stackpole, Kristin; Siegel, Robert; Stratbucker, William; Tucker, Jared M; Christison, Amy L; Hossain, Jobayer; Gentile, Douglas A

2017-02-01

Prior studies show seven percent to nine percent of children demonstrate gaming behaviors that affect a child's ability to function (e.g., problem gaming), but none have examined the association between problem gaming and weight status. The objective of this study was to determine the prevalence of problem gaming among children enrolled in tertiary weight management programs. We administered a computer-based survey to a convenience sample of children aged 11-17 years enrolled in five geographically diverse pediatric weight management (PWM) programs in the COMPASS (Childhood Obesity Multi-Program Analysis and Study System) network. The survey included demographics, gaming characteristics, and a problem gaming assessment. The survey had 454 respondents representing a diverse cohort (53 percent females, 27 percent black, 24 percent Hispanic, 41 percent white) with mean age of 13.7 years. A total of 8.2 percent of respondents met criteria for problem gaming. Problem gamers were more likely to be white, male, play mature-rated games, and report daily play. Children in PWM programs reported problem gaming at the same rate as other pediatric populations. Screening for problem gaming provides an opportunity for pediatricians to address gaming behaviors that may affect the health of children with obesity who already are at risk for worsened health and quality of life.

Problem Video Gaming Among Children Enrolled in Tertiary Weight Management Programs

PubMed Central

Datto, George; Phan, Thao-Ly T.; Werk, Lloyd N.; Stackpole, Kristin; Siegel, Robert; Stratbucker, William; Tucker, Jared M.; Christison, Amy L.; Hossain, Jobayer; Gentile, Douglas A.

2017-01-01

Abstract Prior studies show seven percent to nine percent of children demonstrate gaming behaviors that affect a child's ability to function (e.g., problem gaming), but none have examined the association between problem gaming and weight status. The objective of this study was to determine the prevalence of problem gaming among children enrolled in tertiary weight management programs. We administered a computer-based survey to a convenience sample of children aged 11–17 years enrolled in five geographically diverse pediatric weight management (PWM) programs in the COMPASS (Childhood Obesity Multi-Program Analysis and Study System) network. The survey included demographics, gaming characteristics, and a problem gaming assessment. The survey had 454 respondents representing a diverse cohort (53 percent females, 27 percent black, 24 percent Hispanic, 41 percent white) with mean age of 13.7 years. A total of 8.2 percent of respondents met criteria for problem gaming. Problem gamers were more likely to be white, male, play mature-rated games, and report daily play. Children in PWM programs reported problem gaming at the same rate as other pediatric populations. Screening for problem gaming provides an opportunity for pediatricians to address gaming behaviors that may affect the health of children with obesity who already are at risk for worsened health and quality of life. PMID:28170312

Steady induction effects in geomagnetism. Part 1C: Geomagnetic estimation of steady surficial core motions: Application to the definitive geomagnetic reference field models

NASA Technical Reports Server (NTRS)

Voorhies, Coerte V.

1993-01-01

In the source-free mantle/frozen-flux core magnetic earth model, the non-linear inverse steady motional induction problem was solved using the method presented in Part 1B. How that method was applied to estimate steady, broad-scale fluid velocity fields near the top of Earth's core that induce the secular change indicated by the Definitive Geomagnetic Reference Field (DGRF) models from 1945 to 1980 are described. Special attention is given to the derivation of weight matrices for the DGRF models because the weights determine the apparent significance of the residual secular change. The derived weight matrices also enable estimation of the secular change signal-to-noise ratio characterizing the DGRF models. Two types of weights were derived in 1987-88: radial field weights for fitting the evolution of the broad-scale portion of the radial geomagnetic field component at Earth's surface implied by the DGRF's, and general weights for fitting the evolution of the broad-scale portion of the scalar potential specified by these models. The difference is non-trivial because not all the geomagnetic data represented by the DGRF's constrain the radial field component. For radial field weights (or general weights), a quantitatively acceptable explication of broad-scale secular change relative to the 1980 Magsat epoch must account for 99.94271 percent (or 99.98784 percent) of the total weighted variance accumulated therein. Tolerable normalized root-mean-square weighted residuals of 2.394 percent (or 1.103 percent) are less than the 7 percent errors expected in the source-free mantle/frozen-flux core approximation.

Association between cesarean delivery rate and body mass index.

PubMed

Berendzen, Jodi A; Howard, Bobby C

2013-01-01

The purpose of this study was to evaluate the association between cesarean delivery rate and body mass index (BMI) for the patient population served by the University of Tennessee Medical Center in Knoxville, TN. A retrospective, cohort study was conducted using the perinatal birthlog fromJanuary 1, 2009 through December 31, 2009. The database totaled 2,399 women. Women who delivered > or = 23 weeks gestational age were included. Those missing data imperative to our study (height, weight, mode of delivery) were excluded. Thus, our study included 2,235 women. Cesarean delivery rate was calculated for each of the five BMI categories. Univariate analysis using Chi square, Mann-Whitney U test and independent t-test were used to describe associations between body mass index, mode of delivery and other independent variables. Additional analyses were made on the subset of nulliparous women. Using prepregnancy BMI, 6.7 percent of our population was underweight, 44.3 percent normal weight, 22.6 percent overweight, 20.6 percent obese, and 5.8 percent morbidly obese. The overall cesarean delivery rate was 36.2 percent. Twenty-six percent of underweight and 31.4 percent of normal weight women required cesarean delivery, while 39.1 percent of overweight, 40.8 percent of obese and 56.6 percent of morbidly obese women required cesarean delivery. In addition to cesarean delivery, hypertensive disorders (OR 3.29; 95% CI 2.51-4.31) and diabetes (OR 5.27; 95% CI 3.73-7.44) complicated significantly more pregnancies of obese women than normal weight women. There was an increased rate of cesarean delivery as BMI increased. Increased BMI is also associated with other pregnancy complications, including hypertensive disorders and diabetes.

77 FR 54900 - Aluminum Extrusions From the People's Republic of China: Final Results of Changed Circumstances...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-06

..., with manganese accounting for not more than 3.0 percent of total materials by weight. The subject... number 6 contains magnesium and silicon as the major alloying elements, with magnesium accounting for at least 0.1 percent but not more than 2.0 percent of total materials by weight, and silicon accounting for...

12 CFR 217.152 - Simple risk weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... than or equal to -1 (that is, between zero and -1), then E equals the absolute value of RVC. If RVC is... this section. (1) Zero percent risk weight equity exposures. An equity exposure to an entity whose credit exposures are exempt from the 0.03 percent PD floor in § 217.131(d)(2) is assigned a zero percent...

Exploratory Investigation of Advanced-Temperature Nickel-Base Alloys

NASA Technical Reports Server (NTRS)

Freche, John C.; Waters, William J.

1959-01-01

An investigation was conducted to provide an advanced-temperature nickel-base alloy with properties suitable for aircraft turbine blades as well as for possible space vehicle applications. An entire series of alloys that do not require vacuum melting techniques and that generally provide good stress-rupture and impact properties was evolved. The basic-alloy composition of 79 percent nickel, 8 percent molybdenum, 6 percent chromium, 6 percent aluminum, and 1 percent zirconium was modified by a series of element additions such as carbon, titanium, and boron, with the nickel content adjusted to account for the additives. Stress-rupture, impact, and swage tests were made with all the alloys. The strongest composition (basic alloy plus 1.5 percent titanium plus 0.125 percent carbon) displayed 384- and 574-hour stress-rupture lives at 1800 F and 15,000 psi in the as-cast and homogenized conditions, respectively. All the alloys investigated demonstrated good impact resistance. Several could not be broken in a low-capacity Izod impact tester and, on this basis, all compared favorably with several high-strength high-temperature alloys. Swaging cracks were encountered with all the alloys. In several cases, however, these cracks were slight and could be detected only by zyglo examination. Some of these compositions may become amenable to hot working on further development. On the basis of the properties indicated, it appears that several of the alloys evolved, particularly the 1.5 percent titanium plus 0.125 percent carbon basic-alloy modification, could be used for advanced- temperature turbine blades, as well as for possible space vehicle applications.

Lubricant additive concentrate containing isomerized jojoba oil

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

Arndt, G.

1987-05-12

This patent describes a crankcase motor oil additive concentrate intended to be added to a conventional crankcase motor oil to improve its ability to lubricate and protect the engine. The additive concentrate comprises the following components: A petroleum base stock of lubricating quality and viscosity. The base stock comprises from about 13.5 to 90 weight percent of the additive concentrate; a detergent-inhibitor package. The package is present at from about 7 to about 40 weight percent of the concentrate; a supplemental antiwear additive selected from the salts of dialkyl dithiophosporic acids. The additive is present at a level of frommore » about 1 to about 10 weight percent of the concentrate; and a supplemental antiwear additive selected from the class of sulfurized olefins. The additive is present at a level of from about 1 to about 10 weight percent of the concentrate.« less

7 CFR 52.3184 - Grades of dried prunes.

Code of Federal Regulations, 2012 CFR

2012-01-01

... affected by: Not more than 5 percent, by weight, may be affected by: Off-color. End cracks. 1 Skin or flesh... weight, may be affected by: Not more than 1 percent, by weight, may be affected by: Off-color. Poor texture. Mold. Decay. Poor texture. End cracks. Dirt. End cracks. Skin or flesh Foreign material. Skin or...

16 CFR 303.43 - Fiber content tolerances.

Code of Federal Regulations, 2010 CFR

2010-01-01

... as to fiber content percentages if the percentages by weight of any fibers present in the total fiber... stated on the label in excess of 3 percent of the total fiber weight of the product. For example, where... fiber present may vary from a minimum of 37 percent of the total fiber weight of such product to a...

12 CFR 324.52 - Simple risk-weight approach (SRWA).

Code of Federal Regulations, 2014 CFR

2014-01-01

... greater than or equal to −1 (that is, between zero and −1), then E equals the absolute value of RVC. If...) Zero percent risk weight equity exposures. An equity exposure to a sovereign, the Bank for..., an MDB, and any other entity whose credit exposures receive a zero percent risk weight under § 324.32...

77 FR 71776 - Certain Steel Threaded Rod From the People's Republic of China: Affirmative Preliminary...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-04

... more chromium, by weight, produced by Gem-Year Industrial Co., Ltd. (``Gem- Year''), and otherwise... greater than 1.25 percent chromium, by weight, and otherwise meeting the requirements of the scope of the... threaded rod products with 1.25 percent or more chromium, by weight, produced by Gem-Year, and otherwise...

Differentiation of Asteroid 4 Vesta: Core Formation by Iron Rain in a Silicate Magma Ocean

NASA Technical Reports Server (NTRS)

Kiefer, Walter S.; Mittlefehldt, David W.

2017-01-01

Geochemical observations of the eucrite and diogenite meteorites, together with observations made by NASA's Dawn spacecraft while orbiting asteroid 4 Vesta, suggest that Vesta resembles H chondrites in bulk chemical composition, possible with about 25 percent of a CM-chondrite like composition added in. For this model, the core is 15 percent by mass (or 8 percent by volume) of the asteroid, with a composition of 73.7 percent by weight Fe, 16.0 percent by weight S, and 10.3 percent by weight Ni. The abundances of moderately siderophile elements (Ni, Co, Mo, W, and P) in eucrites require that essentially all of the metallic phase in Vesta segregated to form a core prior to eucrite solidification. The combination of the melting phase relationships for the silicate and metal phases, together with the moderately siderophile element concentrations together require that complete melting of the metal phase occurred (temperature is greater than1350 degrees Centigrade), along with substantial (greater than 40 percent) melting of the silicate material. Thus, core formation on Vesta occurs as iron rain sinking through a silicate magma ocean.

Development of Improved Environmental Resistant Organic-Reinforced Materials Systems

DTIC Science & Technology

1975-11-01

Advanced composites , graphite and boron reinforced laminates, moisture resistance, environmental resistance, organic matrix composites . 20. ABSTRACT...in November 1975 for publication. Efforts at TOD were conducted within the Advanced Composites Engineering Departmfntrunde; L technical...weight makes^organic matrix advanced composites hardware extremely attractive for today s modern Air Force weapons systems. Accordingly, such

A Military Guide to Terrorism in the Twenty-First Century. U.S. Army DCSINT Handbook No. 1 (Version 3.0)

DTIC Science & Technology

2005-08-15

or varnished brown Length: 102mm Width: 61mm Weight: 773g Filler: Amatol Characteristics Color: Black and unmarked Length: 131mm Width: 55mm...isocyanate Diborane Boron tribromide Nitrogen dioxide Ethylene oxide Carbon monoxide Phosphine Fluorine Carbonyl sulfide Phosphorus oxychloride

Lamination residual stresses in fiber composites

NASA Technical Reports Server (NTRS)

Daniel, I. M.; Liber, T.

1975-01-01

An experimental investigation was conducted to determine the magnitude of lamination residual stresses in angle-ply composites and to evaluate their effects on composite structural integrity. The materials investigated were boron/epoxy, boron/polyimide, graphite/low modulus epoxy, graphite/high modulus epoxy, graphite/polyimide and s-glass/epoxy. These materials were fully characterized. Static properties of laminates were also determined. Experimental techniques using embedded strain gages were developed and used to measure residual strains during curing. The extent of relaxation of lamination residual stresses was investigated. It was concluded that the degree of such relaxation is low. The behavior of angle-ply laminates subjected to thermal cycling, tensile load cycling, and combined thermal cycling with tensile load was investigated. In most cases these cycling programs did not have any measurable influence on residual strength and stiffness of the laminates. In the tensile load cycling tests, the graphite/polyimide shows the highest endurance with 10 million cycle runouts at loads up to 90 percent of the static strength.

Modeling stiffness loss in boron/aluminum below the fatigue limit

NASA Technical Reports Server (NTRS)

Johnson, W. S.

1982-01-01

Boron/aluminum can develop significant internal matrix cracking when fatigued. These matrix cracks can result in a 40 percent secant modulus loss in some laminates, even when fatigued below the fatigue limit. It is shown that the same amount of fatigue damage will develop during stress or strain-controlled tests. Stacking sequence has little influence on secant modulus loss. The secant modulus loss in unidirectional composites is small, whereas the losses are substantial in laminates containing off-axis plies. A simple analysis is presented that predicts unnotched laminate secant modulus loss due to fatigue. The analysis is based upon the elastic modulus and Poisson's ratio of the fiber and matrix, fiber volume fraction, fiber orientations, and the cyclic-hardened yield stress of the matrix material. Excellent agreement was achieved between model predictions and experimental results. With this model, designers can project the material stiffness loss for design load or strain levels and assess the feasibility of its use in stiffness-critical parts.

Earth Observation taken during the Expedition 37 mission

NASA Image and Video Library

2013-10-30

ISS037-E-022990 (30 Oct. 2013) --- This detailed image, photographed by an Expedition 37 crew member on the International Space Station, features the former US Borax mine located to the northwest of Boron, California. The mine, currently owned by the Rio Tinto Group, is the largest open-pit mine in California (covering approximately 54 square kilometers) and is among the largest borate mines in the world. Borates, chemical compounds that include the element boron (B), are important both as providers of an essential plant micronutrient, for metallurgical applications, and as components of specialized types of glass, anticorrosive coatings, fire retardants, and detergents (among other uses). Borate minerals such as borax, kernite, and ulexite are found in deposits at the Rio Tinto borax mine. The geologic setting is a structural, nonmarine basin ? a permanent shallow lake ? fed by thermal springs rich in sodium and boron that existed approximately 16 million years ago, according to scientists. The first mining claim in the area was filed in 1913, following discovery of boron-bearing nodules during well drilling. Much of the mine workings were underground until 1957, when US Borax changed to open-pit mining. The open pit is clearly visible at center; concentric benches along the pit wall are accentuated by shadows and mark successive levels of material extraction. Mine tailings are visible as stacked terraces along the northern boundary of the mine. Ore processing facilities occupy a relatively small percentage of the mine area, and are located directly to the west of the open pit. The Rio Tinto mine is one of the Earth?s richest borate deposits; together with mines in Argentina, they produce almost 40 percent of the world?s supply of industrial borate minerals.

Effect of particle size and percentages of Boron carbide on the thermal neutron radiation shielding properties of HDPE/B4C composite: Experimental and simulation studies

NASA Astrophysics Data System (ADS)

Soltani, Zahra; Beigzadeh, Amirmohammad; Ziaie, Farhood; Asadi, Eskandar

2016-10-01

In this paper the effects of particle size and weight percentage of the reinforcement phase on the absorption ability of thermal neutron by HDPE/B4C composites were investigated by means of Monte-Carlo simulation method using MCNP code and experimental studies. The composite samples were prepared using the HDPE filled with different weight percentages of Boron carbide powder in the form of micro and nano particles. Micro and nano composite were prepared under the similar mixing and moulding processes. The samples were subjected to thermal neutron radiation. Neutron shielding efficiency in terms of the neutron transmission fractions of the composite samples were investigated and compared with simulation results. According to the simulation results, the particle size of the radiation shielding material has an important role on the shielding efficiency. By decreasing the particle size of shielding material in each weight percentages of the reinforcement phase, better radiation shielding properties were obtained. It seems that, decreasing the particle size and homogeneous distribution of nano forms of B4C particles, cause to increase the collision probability between the incident thermal neutron and the shielding material which consequently improve the radiation shielding properties. So, this result, propose the feasibility of nano composite as shielding material to have a high performance shielding characteristic, low weight and low thick shielding along with economical benefit.

7 CFR 810.206 - Grades and grade requirements for barley.

Code of Federal Regulations, 2010 CFR

2010-01-01

... weight per bushel (pounds) Sound barley (percent) Maximum Limits of— Damaged kernels 1 (percent) Heat damaged kernels (percent) Foreign material (percent) Broken kernels (percent) Thin barley (percent) U.S... or otherwise of distinctly low quality. 1 Includes heat-damaged kernels. Injured-by-frost kernels and...

High quality interlayer dielectric for 4H SiC DMOSFETs

NASA Astrophysics Data System (ADS)

Okayama, T.; Arthur, S. D.; Waldrab, P.; Rao, Mulpuri V.

2007-11-01

In this work useful weight percentages of boron and phosphorus in boro-phospho-silicate-glass (BPSG) interlayer dielectric (ILD) films to getter mobile ions effectively in 4H-SiC DMOSFET structures are developed, considering the limitations, such as the required low glass flow temperature, and the possible hygroscopic nature of the films and formation of crystalline BPO4 particles, which may occur for high B and P weight percentages. The B and P weight percentage viscous flow temperature contours and empirical inequalities representing the above-mentioned limitations are developed and discussed. Results of this work are useful for both silicon and compound semiconductor device technologies.

In vivo prompt gamma neutron activation analysis for the screening of boron-10 distribution in a rabbit knee: a simulation study

NASA Astrophysics Data System (ADS)

Zhu, X.; Clackdoyle, R.; Shortkroff, S.; Yanch, J.

2008-05-01

Boron neutron capture synovectomy (BNCS) is under development as a potential treatment modality for rheumatoid arthritis (RA). RA is characterized by the inflammation of the synovium (the membrane lining articular joints), which leads to pain and a restricted range of motion. BNCS is a two-part procedure involving the injection of a boronated compound directly into the diseased joint followed by irradiation with a low-energy neutron beam. The neutron capture reactions taking place in the synovium deliver a local, high-linear energy transfer (LET) dose aimed at destroying the inflamed synovial membrane. For successful treatment via BNCS, a boron-labeled compound exhibiting both high synovial uptake and long retention time is necessary. Currently, the in vivo uptake behavior of potentially useful boronated compounds is evaluated in the knee joints of rabbits in which arthritis has been induced. This strategy involves the sacrifice and dissection of a large number of animals. An in vivo 10B screening approach is therefore under investigation with the goal of significantly reducing the number of animals needed for compound evaluation via dissection studies. The 'in vivo prompt gamma neutron activation analysis' (IVPGNAA) approach uses a narrow neutron beam to irradiate the knee from several angular positions following the intra-articular injection of a boronated compound whose uptake characteristics are unknown. A high-purity germanium detector collects the 478 keV gamma photons produced by the 10B capture reactions. The 10B distribution in the knee is then reconstructed by solving a system of simultaneous equations using a weighted least squares algorithm. To study the practical feasibility of IVPGNAA, simulation data were generated with the Monte Carlo N-particle transport code. The boron-containing region of a rabbit knee was partitioned into 8 compartments, and the 10B prompt gamma signals were tallied from 16 angular positions. Results demonstrate that for this level of spatial resolution, an estimate of 10B distribution inside the joint can be obtained to within 10% uncertainty, under ideal conditions. Variations of the anatomic dimensions among individual rabbit knees and potential knee positioning errors will result in an uncertainty of over 20%. IVPGNAA thus provides sufficient resolution and quantification regarding the in vivo uptake characteristics of boronated pharmaceuticals to serve as a useful means of screening new compounds of potential use in BNCS.

Vapor pressures and calculated heats of vaporization of concentrated nitric acid solutions in the composition range 71 to 89 percent nitrogen dioxide, 1 to 10 percent water, and in the temperature range 10 to 60 degrees C

NASA Technical Reports Server (NTRS)

Mckeown, A B; Belles, Frank E

1954-01-01

Total vapor pressures were measured for 16 acid mixtures of the ternary system nitric acid, nitrogen dioxide, and water within the temperature range 10 degrees to 60 degrees Celsius, and with the composition range 71 to 89 weight percent nitric acid, 7 to 20 weight percent nitrogen dioxide, and 1 to 10 weight percent water. Heats of vaporization were calculated from the vapor pressure measurements for each sample for the temperatures 25, 40, and 60 degrees Celsius. The ullage of the apparatus used for the measurements was 0.46. Ternary diagrams showing isobars as a function of composition of the system were constructed from experimental and interpolated data for the temperatures 25, 40, 45, and 60 degrees C and are presented herein.

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of whole-water recoverable arsenic, boron, and vanadium using inductively coupled plasma-mass spectrometry

USGS Publications Warehouse

Garbarino, John R.

2000-01-01

Analysis of in-bottle digestate by using the inductively coupled plasma?mass spectrometric (ICP?MS) method has been expanded to include arsenic, boron, and vanadium. Whole-water samples are digested by using either the hydrochloric acid in-bottle digestion procedure or the nitric acid in-bottle digestion procedure. When the hydrochloric acid in-bottle digestion procedure is used, chloride must be removed from the digestate by subboiling evaporation before arsenic and vanadium can be accurately determined. Method detection limits for these elements are now 10 to 100 times lower than U.S. Geological Survey (USGS) methods using hydride generation? atomic absorption spectrophotometry (HG? AAS) and inductively coupled plasma? atomic emission spectrometry (ICP?AES), thus providing lower variability at ambient concentrations. The bias and variability of the methods were determined by using results from spike recoveries, standard reference materials, and validation samples. Spike recoveries in reagent-water, surface-water, ground-water, and whole-water recoverable matrices averaged 90 percent for seven replicates; spike recoveries were biased from 25 to 35 percent low for the ground-water matrix because of the abnormally high iron concentration. Results for reference material were within one standard deviation of the most probable value. There was no significant difference between the results from ICP?MS and HG?AAS or ICP?AES methods for the natural whole-water samples that were analyzed.

Dietary boron does not affect tooth strength, micro-hardness, and density, but affects tooth mineral composition and alveolar bone mineral density in rabbits fed a high-energy diet.

PubMed

Hakki, Sema S; SiddikMalkoc; Dundar, Niyazi; Kayis, Seyit Ali; Hakki, Erdogan E; Hamurcu, Mehmet; Baspinar, Nuri; Basoglu, Abdullah; Nielsen, Forrest H; Götz, Werner

2015-01-01

The objective of this study was to determine whether dietary boron (B) affects the strength, density and mineral composition of teeth and mineral density of alveolar bone in rabbits with apparent obesity induced by a high-energy diet. Sixty female, 8-month-old, New Zealand rabbits were randomly assigned for 7 months into five groups as follows: (1) control 1, fed alfalfa hay only (5.91 MJ/kg and 57.5 mg B/kg); (2) control 2, high energy diet (11.76 MJ and 3.88 mg B/kg); (3) B10, high energy diet + 10 mg B gavage/kg body weight/96 h; (4) B30, high energy diet + 30 mg B gavage/kg body weight/96 h; (5) B50, high energy diet + 50 mg B gavage/kg body weight/96 h. Maxillary incisor teeth of the rabbits were evaluated for compression strength, mineral composition, and micro-hardness. Enamel, dentin, cementum and pulp tissue were examined histologically. Mineral densities of the incisor teeth and surrounding alveolar bone were determined by using micro-CT. When compared to controls, the different boron treatments did not significantly affect compression strength, and micro-hardness of the teeth, although the B content of teeth increased in a dose-dependent manner. Compared to control 1, B50 teeth had decreased phosphorus (P) concentrations. Histological examination revealed that teeth structure (shape and thickness of the enamel, dentin, cementum and pulp) was similar in the B-treated and control rabbits. Micro CT evaluation revealed greater alveolar bone mineral density in B10 and B30 groups than in controls. Alveolar bone density of the B50 group was not different than the controls. Although the B treatments did not affect teeth structure, strength, mineral density and micro-hardness, increasing B intake altered the mineral composition of teeth, and, in moderate amounts, had beneficial effects on surrounding alveolar bone.

Shielding materials for highly penetrating space radiations

NASA Technical Reports Server (NTRS)

Kiefer, Richard L.; Orwoll, Robert A.

1995-01-01

Interplanetary travel involves the transfer from an Earth orbit to a solar orbit. Once outside the Earth's magnetosphere, the major sources of particulate radiation are solar cosmic rays (SCR's) and galactic cosmic rays (GCR's). Intense fluxes of SCR's come from solar flares and consist primarily of protons with energies up to 1 GeV. The GCR consists of a low flux of nuclei with energies up to 10(exp 10) GeV. About 70 percent of the GCR are protons, but a small amount (0.6 percent) are nuclei with atomic numbers greater than 10. High energy charged particles (HZE) interact with matter by transferring energy to atomic electrons in a Coulomb process and by reacting with an atomic nucleus. Energy transferred in the first process increases with the square of the atomic number, so particles with high atomic numbers would be expected to lose large amounts of energy by this process. Nuclear reactions produced by (HZE) particles produce high-energy secondary particles which in turn lose energy to the material. The HZE nuclei are a major concern for radiation protection of humans during interplanetary missions because of the very high specific ionization of both primary and secondary particles. Computer codes have been developed to calculate the deposition of energy by very energetic charged particles in various materials. Calculations show that there is a significant buildup of secondary particles from nuclear fragmentation and Coulomb dissociation processes. A large portion of these particles are neutrons. Since neutrons carry no charge, they only lose energy by collision or reaction with a nucleus. Neutrons with high energies transfer large amounts of energy by inelastic collisions with nuclei. However, as the neutron energy decreases, elastic collisions become much more effective for energy loss. The lighter the nucleus, the greater the fraction of the neutron's kinetic energy that can be lost in an elastic collision. Thus, hydrogen-containing materials such as polymers are most effective in reducing the energy of neutrons. Once neutrons are reduced to very low energies, the probability for undergoing a reaction with a nucleus (the cross section) becomes very high. The product of such a reaction is often radioactive and can involve the release of a significant amount of energy. Thus, it is important to provide protection from low energy neutrons during a long duration space flight. Among the light elements, lithium and boron each have an isotope with a large thermal neutron capture cross section, Li-6 and B-10. However, B-10 is more abundant in the naturally-occurring element than Li-6, has a thermal neutron capture cross section four times that of Li-6, and produces the stable products, He-4 and Li-7 in the interaction while Li-6 produces radioactive tritium (H-3). Thus, boron is the best light-weight material for thermal neutron absorption in spacecraft. The work on this project was focused in two areas: computer design where existing computer codes were used, and in some cases modified, to calculate the propagation and interactions of high energy charged particles through various media, and materials development where boron was incorporated into high performance materials.

Characterization and Air Drying of Chunkwood and Chips

Treesearch

Joseph B. Sturos

1984-01-01

Chunkwood was found to be composed of a few large particles and many small particles with the large particles constituting almost half the total weight. More than 75 percent of the chunk weight was composed of particles weighing more than 100 grams (ovendry), while 85 percent of the chip weight was composed of particles weighing 3 grams or less. Energy densities...

49 CFR 393.42 - Brakes required on all wheels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... subject to this part is not required to be equipped with brakes if the axle weight of the towed vehicle does not exceed 40 percent of the sum of the axle weights of the towing vehicle. (4) Any full trailer... of the towed vehicle does not exceed 40 percent of the sum of the axle weights of the towing vehicle...

49 CFR Appendix D to Part 173 - Test Methods for Dynamite (Explosive, Blasting, Type A)

Code of Federal Regulations, 2011 CFR

2011-10-01

... weighed to determine the percent of weight loss. 3. Test method D-3—Compression Exudation Test The entire... from the glass tube and weighed to determine the percent of weight loss. EC02MR91.067 ... assembly is placed under the compression rod, and compression is applied by means of the weight on the...

Launch Vehicle Performance for Bipropellant Propulsion Using Atomic Propellants With Oxygen

NASA Technical Reports Server (NTRS)

Palaszewski, Bryan

2000-01-01

Atomic propellants for bipropellant launch vehicles using atomic boron, carbon, and hydrogen were analyzed. The gross liftoff weights (GLOW) and dry masses of the vehicles were estimated, and the 'best' design points for atomic propellants were identified. Engine performance was estimated for a wide range of oxidizer to fuel (O/F) ratios, atom loadings in the solid hydrogen particles, and amounts of helium carrier fluid. Rocket vehicle GLOW was minimized by operating at an O/F ratio of 1.0 to 3.0 for the atomic boron and carbon cases. For the atomic hydrogen cases, a minimum GLOW occurred when using the fuel as a monopropellant (O/F = 0.0). The atomic vehicle dry masses are also presented, and these data exhibit minimum values at the same or similar O/F ratios as those for the vehicle GLOW. A technology assessment of atomic propellants has shown that atomic boron and carbon rocket analyses are considered to be much more near term options than the atomic hydrogen rockets. The technology for storing atomic boron and carbon has shown significant progress, while atomic hydrogen is not able to be stored at the high densities needed for effective propulsion. The GLOW and dry mass data can be used to estimate the cost of future vehicles and their atomic propellant production facilities. The lower the propellant's mass, the lower the overall investment for the specially manufactured atomic propellants.

Safety assessment of boron by application of new uncertainty factors and their subdivision.

PubMed

Hasegawa, Ryuichi; Hirata-Koizumi, Mutsuko; Dourson, Michael L; Parker, Ann; Ono, Atsushi; Hirose, Akihiko

2013-02-01

The available toxicity information for boron was reevaluated and four appropriate toxicity studies were selected in order to derive a tolerable daily intake (TDI) using newly proposed uncertainty factors (UFs) presented in Hasegawa et al. (2010). No observed adverse effect levels (NOAELs) of 17.5 and 8.8 mgB/kg/day for the critical effect of testicular toxicity were found in 2-year rat and dog feeding studies. Also, the 95% lower confidence limit of the benchmark doses for 5% reduction of fetal body weight (BMDL(05)) was calculated as 44.9 and 10.3 mgB/kg/day in mouse and rat developmental toxicity studies, respectively. Measured values available for differences in boron clearance between rats and humans and variability in the glomerular filtration rate (GFR) in pregnant women were used to derive chemical specific UFs. For the remaining uncertainty, newly proposed default UFs, which were derived from the latest applicable information with a probabilistic approach, and their subdivided factors for toxicokinetic and toxicodynamic variability were applied. Finally, overall UFs were calculated as 68 for rat testicular toxicity, 40 for dog testicular toxicity, 247 for mouse developmental toxicity and 78 for rat developmental toxicity. It is concluded that 0.13 mgB/kg/day is the most appropriate TDI for boron, based on rat developmental toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

The Arabidopsis-related halophyte Thellungiella halophila: boron tolerance via boron complexation with metabolites?

PubMed

Lamdan, Netta Li; Attia, Ziv; Moran, Nava; Moshelion, Menachem

2012-04-01

Tolerance to boron (B) is still not completely understood. We tested here the hypothesis that Thellungiella halophila, an Arabidopsis thaliana-related 'extremophile' plant, with abundance of B in its natural environment, is tolerant to B, and examined the potential mechanisms of this tolerance. With 1-10 mm B applied ([B](ext)) to Thellungiella and Arabidopsis grown in hydroponics, the steady-state accumulated B concentration ([B](int)) in the root was below [B](ext), and was similar in both, suggesting both extrude B actively. Whether grown in soil or hydroponically, the shoot [B](int) was higher in Arabidopsis than in Thellungiella, suggesting more effective net B exclusion by Thellungiella root. Arabidopsis exhibited toxicity symptoms including reduced shoot fresh weight (FW), but Thellungiella was not affected, even at similar levels of shoot-accumulated [B](int) (about 10 to 40 mm B in 'shoot water'), suggesting additional B tolerance mechanism in Thellungiella shoot. At [B](ext) = 5 mm, the summed shoot concentration of the potentially B-binding polyhydroxyl metabolites (malic acid, fructose, glucose, sucrose and citric acid) in Arabidopsis was below [B](int) , but in Thellungiella it was over twofold higher than [B](int) , and therefore likely to allow appreciable 1:2 boron-metabolite complexation in the shoot. This, we suggest, is an important component of Thellungiella B tolerance mechanism. © 2011 Blackwell Publishing Ltd.

Thermodynamic stability of boron: the role of defects and zero point motion.

PubMed

van Setten, Michiel J; Uijttewaal, Matthé A; de Wijs, Gilles A; de Groot, Robert A

2007-03-07

Its low weight, high melting point, and large degree of hardness make elemental boron a technologically interesting material. The large number of allotropes, mostly containing over a hundred atoms in the unit cell, and their difficult characterization challenge both experimentalists and theoreticians. Even the ground state of this element is still under discussion. For over 30 years, scientists have attempted to determine the relative stability of alpha- and beta-rhombohedral boron. We use density functional calculations in the generalized gradient approximation to study a broad range of possible beta-rhombohedral structures containing interstitial atoms and partially occupied sites within a 105 atoms framework. The two most stable structures are practically degenerate in energy and semiconducting. One contains the experimental 320 atoms in the hexagonal unit cell, and the other contains 106 atoms in the triclinic unit cell. When populated with the experimental 320 electrons, the 106 atom structure exhibits a band gap of 1.4 eV and an in-gap hole trap at 0.35 eV above the valence band, consistent with known experiments. The total energy of these two structures is 23 meV/B lower than the original 105 atom framework, but it is still 1 meV/B above the alpha phase. Adding zero point energies finally makes the beta phase the ground state of elemental boron by 3 meV/B. At finite temperatures, the difference becomes even larger.

49 CFR 173.57 - Acceptance criteria for new explosives.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (Test Method D-3 in appendix D to this part), a non-gelatin dynamite loses more than 3 percent by weight of the liquid explosive or a gelatin dynamite loses more than 10 percent by weight of the liquid...

49 CFR 173.57 - Acceptance criteria for new explosives.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (Test Method D-3 in appendix D to this part), a non-gelatin dynamite loses more than 3 percent by weight of the liquid explosive or a gelatin dynamite loses more than 10 percent by weight of the liquid...

49 CFR 173.57 - Acceptance criteria for new explosives.

Code of Federal Regulations, 2014 CFR

2014-10-01

... (Test Method D-3 in appendix D to this part), a non-gelatin dynamite loses more than 3 percent by weight of the liquid explosive or a gelatin dynamite loses more than 10 percent by weight of the liquid...

49 CFR 173.57 - Acceptance criteria for new explosives.

Code of Federal Regulations, 2013 CFR

2013-10-01

... (Test Method D-3 in appendix D to this part), a non-gelatin dynamite loses more than 3 percent by weight of the liquid explosive or a gelatin dynamite loses more than 10 percent by weight of the liquid...

Antiretroviral therapy during pregnancy and the risk of an adverse outcome.

PubMed

Tuomala, Ruth E; Shapiro, David E; Mofenson, Lynne M; Bryson, Yvonne; Culnane, Mary; Hughes, Michael D; O'Sullivan, M J; Scott, Gwendolyn; Stek, Alice M; Wara, Diane; Bulterys, Marc

2002-06-13

Some studies suggest that combination antiretroviral therapy in pregnant women with human immunodeficiency virus type 1 (HIV-1) infection increases the risk of premature birth and other adverse outcomes of pregnancy. We studied pregnant women with HIV-1 infection who were enrolled in seven clinical studies and delivered their infants from 1990 through 1998. The cohort comprised 2123 women who received antiretroviral therapy during pregnancy (monotherapy in 1590, combination therapy without protease inhibitors in 396, and combination therapy with protease inhibitors in 137) and 1143 women who did not receive antiretroviral therapy. After standardization for the CD4+ cell count and use or nonuse of tobacco, alcohol, and illicit drugs, the rate of premature delivery (<37 weeks of gestation) was similar among the women who received antiretroviral therapy and those who did not (16 percent and 17 percent, respectively); the rate of low birth weight (<2500 g) was 16 percent among the infants born to both groups; and the rate of very low birth weight (<1500 g) was 2 percent for the group that received antiretroviral therapy and 1 percent for the group that did not. The rates of low Apgar scores (<7) and stillbirth were also similar or the same in the two groups. After adjustment for multiple risk factors, combination antiretroviral therapy was not associated with an increased risk of premature delivery as compared with monotherapy (odds ratio, 1.08; 95 percent confidence interval, 0.71 to 1.62) or delivery of an infant with low birth weight (odds ratio, 1.03; 95 percent confidence interval, 0.64 to 1.63). Seven of the women who received combination therapy with protease inhibitors (5 percent) had infants with very low birth weight, as compared with nine women who received combination therapy without protease inhibitors (2 percent) (adjusted odds ratio, 3.56; 95 percent confidence interval, 1.04 to 12.19). As compared with no antiretroviral therapy or monotherapy, combination therapy for HIV-1 infection in pregnant women is not associated with increased rates of premature delivery or with low birth weight, low Apgar scores, or stillbirth in their infants. The association between combination therapy with protease inhibitors and an increased risk of very low birth weight requires confirmation.

Preliminary design characteristics of a subsonic business jet concept employing laminar flow control

NASA Technical Reports Server (NTRS)

Turriziani, R. V.; Lovell, W. A.; Price, J. E.; Quartero, C. B.; Washburn, G. F.

1978-01-01

Aircraft configurations were developed with laminar flow control (LFC) and without LFC. The LFC configuration had approximately eleven percent less parasite drag and a seven percent increase in the maximum lift-to drag ratio. Although these aerodynamic advantages were partially offset by the additional weight of the LFC system, the LFC aircraft burned from six to eight percent less fuel for comparable missions. For the trans-atlantic design mission with the gross weight fixed, the LFC configuration would carry a greater payload for ten percent fuel per passenger mile.

Effect of moisture loss on red oak sawlog weight

Treesearch

Edward L. Adams

1971-01-01

A study was made to determine the effect of moisture loss on the weights of red oak sawlogs. The logs, ranging from 9 to 21 inches in scaling diameter and from 8 to 14 feet in length, were dried for a 12-week period. The 21-log sample lost 7.6 percent of the total green sawlog weight. The weight loss for individual logs ranged from 5.3 to 14.5 percent. In general, as...

Effects of hypochlorous acid exposure on the rejection of salt, polyethylene glycols, boron and arsenic(V) by nanofiltration and reverse osmosis membranes.

PubMed

Do, Van Thanh; Tang, Chuyang Y; Reinhard, Martin; Leckie, James O

2012-10-15

The separation layer of polyamide-based (PA) thin film composite (TFC) membranes can be modified by active chlorine species. The PA-TFC membranes, NF90, BW30 and NF270, were exposed to different concentrations of sodium hypochlorite (NaOCl) at pH 5 for 24 h. Elemental composition obtained from X-ray Photoelectron Spectroscopy (XPS) showed that the chlorine content in the PA layer increased with the chlorine concentrations. Treatment of membranes with 10 ppm Cl increased the membrane hydrophilicity. By contrast, when treated with 1000 ppm Cl or more, the membranes became less hydrophilic. Water permeability values for all 3 membrane types declined with increased chlorine concentrations. Filtration of polyethylene glycols (PEGs) with molecular weights of 200, 400 and 600 Daltons (Da) was performed to investigate the influence of chlorine treatment on membrane molecular weight cut off (MWCO) and rejection by size exclusion. Treatment with 10 and 100 ppm Cl lowered the MWCO while treatment with higher concentrations increased the MWCO. All chlorinated membranes experienced higher NaCl rejection compared to virgin ones. The performance of NF90 was tested with respect to the rejection of inorganic contaminants including boron (H(3)BO(3)) and arsenic (H(2)AsO(4)(-)). The boron rejection results paralleled PEG rejection whereas those for arsenic followed NaCl rejection patterns. The changes in membrane performance due to chlorine treatment were explained in terms of competing mechanisms: membrane tightening, bond cleavage by N-chlorination and chlorination promoted polyamide hydrolysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

40 CFR Table 3 to Subpart Dddd of... - Work Practice Requirements

Code of Federal Regulations, 2013 CFR

2013-07-01

... with a 24-hour block average inlet moisture content of less than or equal to 30 percent (by weight, dry... average inlet moisture content of the veneer is less than or equal to 25 percent (by weight, dry basis...

21 CFR 177.1520 - Olefin polymers.

Code of Federal Regulations, 2013 CFR

2013-04-01

... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components... (expressed as percent by weight of the polymer) in N-hexane at specified temperatures Maximum soluble fraction (expressed as percent by weight of polymer) in xylene at specified temperatures 1.1a...

21 CFR 177.1520 - Olefin polymers.

Code of Federal Regulations, 2012 CFR

2012-04-01

... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components... (expressed as percent by weight of the polymer) in N-hexane at specified temperatures Maximum soluble fraction (expressed as percent by weight of polymer) in xylene at specified temperatures 1.1a...

Gd-doped BNNTs as T2-weighted MRI contrast agents

NASA Astrophysics Data System (ADS)

Ciofani, Gianni; Boni, Adriano; Calucci, Lucia; Forte, Claudia; Gozzi, Alessandro; Mazzolai, Barbara; Mattoli, Virgilio

2013-08-01

This work describes, for the first time, doping of boron nitride nanotubes (BNNTs) with gadolinium (Gd@BNNTs), a stable functionalization that permits non-invasive BNNT tracking via magnetic resonance imaging (MRI). We report the structure, Gd loading, and relaxometric properties in water suspension at 7 T of Gd@BNNTs, and show the behaviour of these nanostructures as promising T2-weighted contrast agents. Finally, we demonstrate their complete biocompatibility in vitro on human neuroblastoma cells, together with their ability to effectively label and affect contrast in MRI images at 7 T.

Application of a unique test design to determine the chronic toxicity of boron to the aquatic worm Lumbriculus variegatus and fatmucket mussel Lampsilis siliquoidea.

PubMed

Hall, Scott; Lockwood, Rick; Harrass, Michael C

2014-01-01

The chronic (21- and 28-day) toxicity of boron was determined for two freshwater benthic macroinvertebrates: the fatmucket mussel Lampsilis siliquoidea and the aquatic worm Lumbriculus variegatus. The rapid depletion of boric acid from spiked sediments in tests using flow-through overlying waters was addressed by constant addition of boric acid to overlying water at concentrations matching those of the targeted porewater exposures. This proved highly successful in maintaining constant whole-sediment and sediment porewater boron concentrations. Boron sublethal 25 % inhibition concentration values based on porewater concentrations were 25.9 mg B/L (L. variegatus) and 38.5 mg B/L (L. siliquoidea), indicating similar test organism sensitivity. Expressed as dry whole-sediment values, the respective L. variegatus and L. siliquoidea sublethal (growth) IC25 values for whole-sediment exposures were 235.5 mg B/kg sediment dry weight (dw) and 310.6 mg B/kg dw. The worm lethality-based end points indicated greater sensitivity than the sublethal end points, bringing into question the validity of a "lethality" end point for L. variegatus given its fragmentation mode of reproduction. For comparison, water-only mussel exposures were tested resulting in an IC25 value of 34.6 mg B/L, which was within 20 % of the porewater value. This suggests that the primary route of boron exposure was through the aqueous phase. The results of this study indicated that for test materials that are readily water soluble, standard sediment test designs may be unsuitable, but water-only exposures can provide toxicological data representative of sediment tests.

Boron-containing acids: preliminary evaluation of acute toxicity and access to the brain determined by Raman scattering spectroscopy.

PubMed

Soriano-Ursúa, Marvin A; Farfán-García, Eunice D; López-Cabrera, Yessica; Querejeta, Enrique; Trujillo-Ferrara, José G

2014-01-01

Boron-containing compounds (BCCs), particularly boron containing acids (BCAs), have become attractive moieties or molecules in drug development. It has been suggested that when functional groups with boron atoms are added to well-known drugs, the latter are conferred with greater potency and efficacy in relation to their target receptors. However, the use of BCAs in drug development is limited due to the lack of a toxicological profile. Consequently, the aim of the present study was to evaluate the acute toxicity of boric and boronic acids. Thus, a determination was made of the lethal dose (LD50) of test compounds in male CD1 mice, as well as the effective dose required to negatively affect spontaneous motor activity and to produce notable behavioral abnormalities. After treatment of animals at different doses, macroscopic observations were made from a necropsy, and Raman scattering spectroscopic studies were carried out on brain tissue samples. In general, the results show that most of the tested BCAs have very low toxicity, evidenced by the high doses required to induce notable toxic effects (greater than 100 mg/kg of body weight for all compounds, except for 3-thyenilboronic acid). Such toxic effects, presumably mediated by action on the CNS, include eye damage, gastrointestinal effects (e.g., gastric-gut dilatation and fecal retention), sedation, hypnosis and/or trembling. This preliminary toxicological profile suggests that BCAs can be considered potential therapeutic agents or moieties to be added to other compounds in the development of new drugs. Future studies are required to explore possible chronic toxicity of BCCs. Copyright © 2013 Elsevier Inc. All rights reserved.

Patterns of postnatal weight changes in infants with very low and extremely low birth weights.

PubMed

Smith, S L; Kirchhoff, K T; Chan, G M; Squire, S J

1994-01-01

To describe (1) short-term postnatal weight loss and gain patterns in infants with very low and extremely low birth weights and (2) the variables that may affect these weight change patterns. Descriptive, retrospective review. University hospital in the intermountain western United States. Sixty-two charts of infants admitted to a university neonatal intensive care unit from July 1990 through November 1992 were reviewed. Infants who weighed 1000 grams or less were categorized as extremely low birth weight (ELBW) and infants weighing 1001 to 1500 grams were categorized as very low birth weight (VLBW). Each group was comprised of 31 infants. Fifty percent of the sample were male, and 50% were female. Eighty-five percent of the sample were Anglo-American, and 15% were non-Anglo-American. Data were collected on a three-part data collection tool and included demographic and treatment variables. A significant difference was found in the maximum percent weight lost between the two groups, with the ELBW group losing a mean of 14.77% of birth weight and the VLBW group losing a mean of 11.35% of birth weight (t = 2.45, p < 0.05). The day the infants reached their nadir weight was significantly different between the two groups. The ELBW group reached their nadir on day of life 7, and the VLBW group reached their nadir on day of life 6 (t = 2.00, p < 0.05). No significant difference was noted in the time to return to birth weight between the two groups, with a mean of 15 days to return to birth weight. Factors associated with postnatal weight changes were intraventricular hemorrhage, use of diuretics and steroids, day of life when nadir weight occurred, and maximum percent of weight lost. Many of the independent variables were significantly interrelated to each other (r = -0.90 to r = 0.91, p < 0.01 to p < 0.001). However, only the variables that correlated with time to return to birth weight were entered into the regression analysis. These variables included number of days diuretics were given before return to birth weight, maximum percent of weight lost, and day of life the infants reached their nadir weight. Number of days diuretics were given before return to birth weight correlated significantly with time to return to birth weight (r = 0.77, F = 26.66, p < 0.0001) although maximum percent of weight lost and day of life the infants reached their nadir weight had a minimal effect. Further research into the effects of diuretic therapy on weight changes in this population of infants may lead to interventions to minimize the negative effects of diuretics on return to birth weight. In addition, the older growth charts may not be applicable to this population of infants. Generation of new growth charts that provide growth curves based on these data could be useful in developing nutritional therapies that would promote growth and possibly decrease the length of hospital stay for these infants.

Ground-Water Quality and Potential Effects of Individual Sewage Disposal System Effluent on Ground-Water Quality in Park County, Colorado, 2001-2004

USGS Publications Warehouse

Miller, Lisa D.; Ortiz, Roderick F.

2007-01-01

In 2000, the U.S. Geological Survey, in cooperation with Park County, Colorado, began a study to evaluate ground-water quality in the various aquifers in Park County that supply water to domestic wells. The focus of this study was to identify and describe the principal natural and human factors that affect ground-water quality. In addition, the potential effects of individual sewage disposal system (ISDS) effluent on ground-water quality were evaluated. Ground-water samples were collected from domestic water-supply wells from July 2001 through October 2004 in the alluvial, crystalline-rock, sedimentary-rock, and volcanic-rock aquifers to assess general ground-water quality and effects of ISDS's on ground-water quality throughout Park County. Samples were analyzed for physical properties, major ions, nutrients, bacteria, and boron; and selected samples also were analyzed for dissolved organic carbon, human-related (wastewater) compounds, trace elements, radionuclides, and age-dating constituents (tritium and chlorofluorocarbons). Drinking-water quality is adequate for domestic use throughout Park County with a few exceptions. Only about 3 percent of wells had concentrations of fluoride, nitrate, and (or) uranium that exceeded U.S. Environmental Protection Agency national, primary drinking-water standards. These primary drinking-water standards were exceeded only in wells completed in the crystalline-rock aquifers in eastern Park County. Escherichia coli bacteria were detected in one well near Guffey, and total coliform bacteria were detected in about 11 percent of wells sampled throughout the county. The highest total coliform concentrations were measured southeast of the city of Jefferson and west of Tarryall Reservoir. Secondary drinking-water standards were exceeded more frequently. About 19 percent of wells had concentrations of one or more constituents (pH, chloride, fluoride, sulfate, and dissolved solids) that exceeded secondary drinking-water standards. Currently (2004), there is no federally enforced drinking-water standard for radon in public water-supply systems, but proposed regulations suggest a maximum contaminant level of 300 picocuries per liter (pCi/L) and an alternative maximum contaminant level of 4,000 pCi/L contingent on other mitigating remedial activities to reduce radon levels in indoor air. Radon concentrations in about 91 percent of ground-water samples were greater than or equal to 300 pCi/L, and about 25 percent had radon concentrations greater than or equal to 4,000 pCi/L. Generally, the highest radon concentrations were measured in samples collected from wells completed in the crystalline-rock aquifers. Analyses of ground-water-quality data indicate that recharge from ISDS effluent has affected some local ground-water systems in Park County. Because roughly 90 percent of domestic water used is assumed to be recharged by ISDS's, detections of human-related (wastewater) compounds in ground water in Park County are not surprising; however, concentrations of constituents associated with ISDS effluent generally are low (concentrations near the laboratory reporting levels). Thirty-eight different organic wastewater compounds were detected in 46 percent of ground-water samples, and the number of compounds detected per sample ranged from 1 to 17 compounds. Samples collected from wells with detections of wastewater compounds also had significantly higher (p-value < 0.05) chloride and boron concentrations than samples from wells with no detections of wastewater compounds. ISDS density (average subdivision lot size used to estimate ISDS density) was related to ground-water quality in Park County. Chloride and boron concentrations were significantly higher in ground-water samples collected from wells located in areas that had average subdivision lot sizes of less than 1 acre than in areas that had average subdivision lot sizes greater than or equal to 1 acre. For wells completed in the crystalline-

Measuring weight outcomes for obesity intervention strategies: the case of a sugar-sweetened beverage tax.

PubMed

Lin, Biing-Hwan; Smith, Travis A; Lee, Jonq-Ying; Hall, Kevin D

2011-12-01

Taxing unhealthy foods has been proposed as a means to improve diet and health by reducing calorie intake and raising funds to combat obesity, particularly sugar-sweetened beverages (SSBs). A growing number of studies have examined the effects of such food taxes, but few have estimated the weight-loss effects. Typically, a static model of 3500 calories for one pound of body weight is used, and the main objective of the study is to demonstrate its bias. To accomplish the objective, we estimate income-segmented beverage demand systems to examine the potential effects of a SSB tax. Elasticity estimates and a hypothetical 20 percent effective tax rate (or about 0.5 cent per ounce) are applied to beverage intake data from a nationally representative survey, and we find an average daily reduction of 34-47 calories among adults and 40-51 calories among children. The tax-induced energy reductions are translated into weight loss using both static and dynamic calorie-to-weight models. Results demonstrate that the static model significantly overestimates the weight loss from reduced energy intake by 63 percent in year one, 346 percent in year five, and 764 percent in year 10, which leads to unrealistic expectations for obesity intervention strategies. The tax is estimated to generate $5.8 billion a year in revenue and is found to be regressive, although it represents about 1 percent of household food and beverage spending. Published by Elsevier B.V.

A Preliminary Study of the Preparation of Slurry Fuels from Vaporized Magnesium

NASA Technical Reports Server (NTRS)

Witzke, Walter R; Prok, George M; Walsh, Thomas J

1954-01-01

Slurry fuels containing extremely small particles of magnesium were prepared by concentrating the dilute slurry product resulting from the shock-cooling of magnesium metal vapors with a liquid hydrocarbon spray. A complete description of the equipment and procedure used in preparing the fuel is given. Ninety-five percent by weight of the solid particles formed by this process passed through a 100-mesh screen. The particle-size distribution of the screened fraction of one run, as determined by sedimentation analysis, indicated that 73 percent by weight of the metal particles were finer than 2 microns in equivalent spherical diameter. The purity of the solid particles ranged as high as 98.9 percent by weight of free magnesium. The screened product was concentrated by means of a bowl-type centrifuge from 0.5 to more than 50 percent by weight solids content to form an extremely viscous, clay-like mass. By addition of a surface active agent, this viscous material was converted into a pumpable slurry fuel.

Effects of laminar flow control on the performance of a large span-distributed-load flying-wing cargo airplane concept

NASA Technical Reports Server (NTRS)

Jernell, L. S.

1978-01-01

The effects of laminar flow control (LFC) on the performance of a large span-distributed-load flying-wing cargo airplane concept having a design payload of 2.669 MN and range of 5.93 Mm were determined. Two configurations were considered. One employed laminarized flow over the entire surfaces of the wing and vertical tails, with the exception of the estimated areas of interference due to the fuselage and engines. The other case differed only in that laminar flow was not applied to the flaps, elevons, spoilers, or rudders. The two cases are referred to as the 100 percent and 80 percent laminar configurations, respectively. The utilization of laminar flow control results in reductions in the standard day, sea level installed maximum static thrust per engine from 240 kN for the non-LFC configuration to 205 kN for the 100 percent laminar configuration and 209 kN for the 80 percent case. Weight increases due to the LFC systems cause increases in the operating empty weights of approximately 3 to 4 percent. The design takeoff gross weights decrease approximately 3 to 5 percent. The FAR-25 takeoff field distances for the LFC configurations are greater by about 6 to 7 percent. Fuel efficiencies for the respective configurations are increased 33 percent and 23 percent.

Highly water-soluble, porous, and biocompatible boron nitrides for anticancer drug delivery.

PubMed

Weng, Qunhong; Wang, Binju; Wang, Xuebin; Hanagata, Nobutaka; Li, Xia; Liu, Dequan; Wang, Xi; Jiang, Xiangfen; Bando, Yoshio; Golberg, Dmitri

2014-06-24

Developing materials for "Nano-vehicles" with clinically approved drugs encapsulated is envisaged to enhance drug therapeutic effects and reduce the adverse effects. However, design and preparation of the biomaterials that are porous, nontoxic, soluble, and stable in physiological solutions and could be easily functionalized for effective drug deliveries are still challenging. Here, we report an original and simple thermal substitution method to fabricate perfectly water-soluble and porous boron nitride (BN) materials featuring unprecedentedly high hydroxylation degrees. These hydroxylated BNs are biocompatible and can effectively load anticancer drugs (e.g., doxorubicin, DOX) up to contents three times exceeding their own weight. The same or even fewer drugs that are loaded on such BN carriers exhibit much higher potency for reducing the viability of LNCaP cancer cells than free drugs.

Metallized Gelled Propellants: Oxygen/RP-1/Aluminum Rocket Heat Transfer and Combustion Measurements

NASA Technical Reports Server (NTRS)

Palaszewski, Bryan; Zakany, James S.

1996-01-01

A series of rocket engine heat transfer experiments using metallized gelled liquid propellants was conducted. These experiments used a small 20- to 40-lb/f thrust engine composed of a modular injector, igniter, chamber and nozzle. The fuels used were traditional liquid RP-1 and gelled RP-1 with 0-, 5-, and 55-percentage by weight loadings of aluminum particles. Gaseous oxygen was used as the oxidizer. Three different injectors were used during the testing: one for the baseline O(2)/RP-1 tests and two for the gelled and metallized gelled fuel firings. Heat transfer measurements were made with a rocket engine calorimeter chamber and nozzle with a total of 31 cooling channels. Each chamber used a water flow to carry heat away from the chamber and the attached thermocouples and flow meters allowed heat flux estimates at each of the 31 stations. The rocket engine Cstar efficiency for the RP-1 fuel was in the 65-69 percent range, while the gelled 0 percent by weight RP-1 and the 5-percent by weight RP-1 exhibited a Cstar efficiency range of 60 to 62% and 65 to 67%, respectively. The 55-percent by weight RP-1 fuel delivered a 42-47% Cstar efficiency. Comparisons of the heat flux and temperature profiles of the RP-1 and the metallized gelled RP-1/A1 fuels show that the peak nozzle heat fluxes with the metallized gelled O2/RP-1/A1 propellants are substantially higher than the baseline O2/RP-1: up to double the flux for the 55 percent by weight RP-1/A1 over the RP-1 fuel. Analyses showed that the heat transfer to the wall was significantly different for the RP-1/A1 at 55-percent by weight versus the RP-1 fuel. Also, a gellant and an aluminum combustion delay was inferred in the 0 percent and 5-percent by weight RP-1/A1 cases from the decrease in heat flux in the first part of the chamber. A large decrease in heat flux in the last half of the chamber was caused by fuel deposition in the chamber and nozzle. The engine combustion occurred well downstream of the injector face based on the heat flux estimates from the temperature measurements.

Synthesis and analysis of jet fuels from shale oil and coal syncrudes

NASA Technical Reports Server (NTRS)

Antoine, A. C.; Gallagher, J. P.

1976-01-01

The technical problems involved in converting a significant portion of a barrel of either a shale oil or coal syncrude into a suitable aviation turbine fuel were studied. TOSCO shale oil, H-Coal and COED coal syncrudes were the starting materials. They were processed by distillation and hydrocracking to produce two levels of yield (20 and 40 weight percent) of material having a distillation range of approximately 422 to 561 K (300 F to 550 F). The full distillation range 311 to 616 K (100 F to 650 F) materials were hydrotreated to meet two sets of specifications (20 and 40 volume percent aromatics, 13.5 and 12.75 weight percent H, 0.2 and 0.5 weight percent S, and 0.1 and 0.2 weight percent N). The hydrotreated materials were distilled to meet given end point and volatility requirements. The syntheses were carried out in laboratory and pilot plant equipment scaled to produce thirty-two 0.0757 cu m (2-gal)samples of jet fuel of varying defined specifications. Detailed analyses for physical and chemical properties were made on the crude starting materials and on the products.

Examining behavioral processes through which lifestyle interventions promote weight loss: results from PREMIER.

PubMed

Fitzpatrick, Stephanie L; Bandeen-Roche, Karen; Stevens, Victor J; Coughlin, Janelle W; Rubin, Richard R; Brantley, Phillip J; Funk, Kristine L; Svetkey, Laura P; Jerome, Gerald J; Dalcin, Arlene; Charleston, Jeanne; Appel, Lawrence J

2014-04-01

To examine the behavioral processes through which lifestyle interventions impacted weight loss. The analyses were limited to overweight and obese Black and White adults randomized to a PREMIER lifestyle intervention (N = 501). Structural equation modeling was conducted to test the direct and indirect relationships of session attendance, days of self-monitoring diet and exercise, change in diet composition and exercise, and 6-month weight change. Greater session attendance was associated with increased self-monitoring, which was in turn significantly related to reduction in percent energy from total fat consumed. Change in percent energy from fat and self-monitoring was associated with 6-month percent change in weight. Both a decrease in fat intake and increase in self-monitoring are potential mediators of the relationship between attendance and weight change. The findings provide a reasonable model that suggests regular session attendance and use of behavioral strategies like self-monitoring are associated with improved behavioral outcomes that are associated with weight loss. Copyright © 2013 The Obesity Society.

7 CFR 52.1858 - Grades of mixed types or varieties of raisins.

Code of Federal Regulations, 2012 CFR

2012-01-01

... based on the respective requirements for each type, except for moisture, in accordance with this subpart... than 18 percent, by weight, of moisture. Mixed types of processed raisins that as a mixture exceed 18 percent, by weight, of moisture are “Substandard.” ...

Comparison of all-electric secondary power systems for civil transport

NASA Technical Reports Server (NTRS)

Renz, David D.

1992-01-01

Three separate studies have shown operational, weight, and cost advantages for commercial subsonic transport aircraft using an all-electric secondary power system. The first study in 1982 showed that all-electric secondary power systems produced the second largest benefit compared to four other technology upgrades. The second study in 1985 showed a 10 percent weight and fuel savings using an all-electric high frequency (20 kHz) secondary power system. The last study in 1991 showed a 2 percent weight savings using today's technology (400 Hz) in an all-electric secondary power system. This paper will compare the 20 kHz and 400 Hz studies, analyze the 2 to 10 percent difference in weight savings and comment on the common benefits of the all-electric secondary power system.

Comparison of all-electric secondary power systems for civil subsonic transports

NASA Technical Reports Server (NTRS)

Renz, David D.

1992-01-01

Three separate studies have shown operational, weight, and cost advantages for commercial subsonic transport aircraft using an all-electric secondary power system. The first study in 1982 showed that all-electric secondary power systems produced the second largest benefit compared to four other technology upgrades. The second study in 1985 showed a 10 percent weight and fuel savings using an all-electric high frequency (20 kHz) secondary power system. The last study in 1991 showed a 2 percent weight savings using today's technology (400 Hz) in an all-electric secondary power system. This paper will compare the 20 kHz and 400 Hz studies, analyze the 2 to 10 percent difference in weight savings and comment on the common benefits of the all-electric secondary power system.

Weights, growth, and survival of timber wolf pups in Minnesota

USGS Publications Warehouse

Van Ballenberghe, V.; Mech, L.D.

1975-01-01

Weights, growth rates, canine tooth lengths, and survival data were obtained from 73 wild wolf (Canis lupus) pups that were 8 to 28 weeks old when live-trapped in three areas of northern Minnesota from 1969 to 1972. Relative weights of wild pups are expressed as percentages of a standard weight curve based on data from captive pups of similar age. These relative weights varied greatly within litters, between litters, and between years; extremes of 31 to 144 percent of the standard were observed. Growth rates ranging from 0.05 to 0.23 kilograms per day were observed, and similar variations in general devel pment and in replacement and growth of canine teeth were noted. Survival data based on radio-tracking and tag returns indicated that pups with relative weights less than 65 percent of standard have a poor chance of survival, whereas pups of at least 80 percent of standard weight have a high survivability. Pups born in 1972 were especially underweight, probably a result of declining white-tailed deer (Odocoileus virginianus) densities in the interior of the Superior National Forest study area.

Demographic patterns of postfire regeneration in mediterranean-climate shrublands of California

USGS Publications Warehouse

Keeley, J.E.; Fotheringham, C.J.; Baer-Keeley, M.

2006-01-01

Eggs of captive black ducks fed diets containing DDE at 10 and 30 ppm (dry weight) experienced significant shell thinning and an increase in shell cracking when compared to eggs of untreated black ducks. Eggshells from dosed ducks were: 18-24 percent thinner at the equator than shells from undosed ducks; 28-31 percent thinner at the cap; and 29-38 percent thinner at the apex. Shell cracking averaged 21 percent among eggs fram the 30 ppm DDE dosage and 10 percent among eggs from the 10 ppm dosage. Only 2 percent of the eggs from untreated black ducks were cracked. Survival of ducklings fram dosed parents in terms of 'percentage of 21-day ducklings of embryonated eggs' was 40-76 percent lower than survival of ducklings from undosed parents. Average DDE residues (wet weight) in eggs from hens fed 10 and 30 ppm DDE were 46 ppm and 144 ppm, respectively.

21 CFR 178.3505 - Glyceryl tri-(12-acetoxy-stearate).

Code of Federal Regulations, 2010 CFR

2010-04-01

... for use in producing, manufacturing, packing, processing, preparing, treating, packaging, transporting... surface of calcium carbonate at a level not to exceed 1 weight-percent of the total mixture. (b) The... with nonfatty foods at a level not to exceed 20 weight-percent of the polymer. [50 FR 1503, Jan. 11...

40 CFR 63.1362 - Standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... source subject to the provisions of this subpart shall control HAP emissions to the levels specified in... control device, installed on or before November 10, 1997 on a process vent otherwise subject to the... greater than or equal to 90 percent by weight but less than 98 percent by weight, then the control device...

40 CFR 63.1362 - Standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... source subject to the provisions of this subpart shall control HAP emissions to the levels specified in... control device, installed on or before November 10, 1997 on a process vent otherwise subject to the... greater than or equal to 90 percent by weight but less than 98 percent by weight, then the control device...

40 CFR 98.68 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

.../metric tons Al) Individual facility records. Sa: sulfur content in baked anode (percent weight) 2.0. Asha: ash content in baked anode (percent weight) 0.4. CO2 Emissions from Sderberg Cells (VSS and HSS) MP... content in green anodes (metric tons) 0.005 × GA. BA: annual baked anode production (metric tons...

40 CFR 52.1670 - Identification of plans.

Code of Federal Regulations, 2011 CFR

2011-07-01

... percent, by weight, for the Long Island Lighting Co.'s Northport Generating Facility (Units 1, 2, and 3... oil limitation to 1.0 percent, by weight, for the Long Island Lighting Company's Glenwood Generating... of New York, Inc. Arthur Kill generating facility, units 2 and 3, Staten Island, New York and...

Mixtures of a coal combustion by-product and composted yard wastes for use as soil substitutes and amendments. Final report

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

Eckert, D.J.; McCoy, E.L.; Danneberger, T.K.

Mixtures of coal combustion by-product (CCBP) and yard waste compost (with and without sand), and mixtures of CCBP and soil, were evaluated for use as soil substitutes and amendments for production of container-grown ornamental shrubs and trees, and for establishment and production of forage-groundcover species. Species evaluated were azalea (Rhododendron spp.), burning bush (Euonymous alatus), red maple (Acer rubrum), yew (Taxus spp.), tall fescue (Festuca arundi nacea, cv. {open_quotes}Chesapeake{close_quotes}), alfalfa, and Kentucky bluegrass (Poa pratensis L., cv. {open_quotes}Bronco{close_quotes}). All ornamental species failed to grow when planted in CCBP/compost mixtures when the CCBP concentration was greater than 30 percent by volume.more » Plant toxicity due to high concentrations of soluble salts and boron was responsible for the poor plant performance. When CCBP was used as a soil amendment at concentrations less than 30 percent, growth of tall fescue and Kentucky bluegrass was not affected by the mixture, and alfalfa yield increased at CCBP mixtures up to 20 percent.« less

New high boron content polyborane precursors to advanced ceramic materials: New syntheses, new applications

NASA Astrophysics Data System (ADS)

Guron, Marta

There is a need for new synthetic routes to high boron content materials for applications as polymeric precursors to ceramics, as well as in neutron shielding and potential medical applications. To this end, new ruthenium-catalyzed olefin metathesis routes have been devised to form new complex polyboranes and polymeric species. Metathesis of di-alkenyl substituted o-carboranes allowed the synthesis of ring-closed products fused to the carborane cage, many of which are new compounds and one that offers a superior synthetic method to one previously published. Acyclic diene metathesis of di-alkenyl substituted m-carboranes resulted in the formation of new main-chain carborane-containing polymers of modest molecular weights. Due to their extremely low char yields, and in order to explore other metathesis routes, ring opening metathesis polymerization (ROMP) was used to generate the first examples of poly(norbornenyl- o-carboranes). Monomer synthesis was achieved via a two-step process, incorporating Ti-catalyzed hydroboration to make 6-(5-norbornenyl)-decaborane, followed by alkyne insertion in ionic liquid media to achieve 1,2-R2 -3-norbornenyl o-carborane species. The monomers were then polymerized using ROMP to afford several examples of poly(norbornenyl- o-carboranes) with relatively high molecular weights. One such polymer, [1-Ph, 3-(=CH2-C5H7-CH2=)-1,2-C 2B10H10]n, had a char yield very close to the theoretical char yield of 44%. Upon random copolymerization with poly(6-(5-norbornenyl) decaborane), char yields significantly increased to 80%, but this number was well above the theoretical value implicating the formation of a boron-carbide/carbon ceramic. Finally, applications of polyboranes were explored via polymer blends toward the synthesis of ceramic composites and the use of polymer precursors as reagents for potential ultra high temperature ceramic applications. Upon pyrolysis, polymer blends of poly(6-(5-norbornenyl)-decaborane) and poly(methylcarbosilane) converted into boron-carbide/silicon-carbide ceramics with high char yields. These polymer blends were also shown to be useful as reagents for synthesis of hafnium-boride/hafnium-carbide/silicon carbide and zirconium-boride/zirconium-carbide/silicon carbide composites.

Projections of forest contributions to global carbon cycles

Treesearch

Michael E. Goerndt; Stephen R. Shifley; Patrick D. Miles; Dave Wear; Francisco X. Aguilar

2016-01-01

Forests cover 42 percent of the Northern United States, and collectively they store 13 billion tons of carbon in live trees (29 percent), roots (6 percent), forest floor (9 percent), dead trees (6 percent), and soils (50 percent). About half the biomass of a live tree (dry weight basis) is sequestered carbon (Woodall et al. 2011) - not the largest but the most dynamic...

Conceptual Design Studies of Composite AMST

DTIC Science & Technology

1974-10-01

WEIGHT OF THE AIRFRAME THE PROPERTIES OF HIGH -STRENGTH GRAPHITE-EPOXY COMPOSITES (REPRESENTATIVE OF THORNEL 300 FIBERS) WERE USED IN THE APPLICATION...The primary advanced composite material selected was a high -strength graphite-epoxy (Thornel 300/Narmco 5208). Boron-infiltrated aluminum extrusions...Figure Page 25 Trimming Irregular Cutouts in Wing Box Attach Angles ...... 71 26 Hydroforming W-Truss Web Beaded Panels ................ 72 27 Exploded

Effects of nano-sized boron nitride (BN) reinforcement in expandable graphite based in-tumescent fire retardant coating

NASA Astrophysics Data System (ADS)

Zulkurnain, E. S.; Ahmad, F.; Gillani, Q. F.

2016-08-01

The purpose of in-tumescent fire retardant coating (IFRC) is to protect substrate from fire attack by limiting heat transfer. A range of coating formulations have been prepared using Bisphenol A epoxy resin BE-188 and polyamide solidifier H-2310 as two-part binder, ammonium polyphosphate (APP) as acid source, melamine (MEL) as the blowing agent, expandable graphite (EG) as carbon source and nano-boron nitride (BN) as inorganic nano filler. The filler was used to improve the performances of the APP-EG-MEL coating. The effects of nano-BN on the char morphology and thermal degradation were investigated by fire test, thermo gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X- ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). The results showed that by substituting or reinforcing of 4% weight percentage of nano-BN, residual weight of the char increases by 23.82% compared to APP-EG-MEL coating without filler. Higher carbon content was obtained in the char and a more compact char was produced. The results indicated that nano-BN could be used as a filler to improve thermal stability of the APP-EG-MEL coating.

Weight savings in aerospace vehicles through propellant scavenging

NASA Technical Reports Server (NTRS)

Schneider, Steven J.; Reed, Brian D.

1988-01-01

Vehicle payload benefits of scavenging hydrogen and oxygen propellants are addressed. The approach used is to select a vehicle and a mission and then select a scavenging system for detailed weight analysis. The Shuttle 2 vehicle on a Space Station rendezvous mission was chosen for study. The propellant scavenging system scavenges liquid hydrogen and liquid oxygen from the launch propulsion tankage during orbital maneuvers and stores them in well insulated liquid accumulators for use in a cryogenic auxiliary propulsion system. The fraction of auxiliary propulsion propellant which may be scavenged for propulsive purposes is estimated to be 45.1 percent. The auxiliary propulsion subsystem dry mass, including the proposed scavenging system, an additional 20 percent for secondary structure, an additional 5 percent for electrical service, a 10 percent weight growth margin, and 15.4 percent propellant reserves and residuals is estimated to be 6331 kg. This study shows that the fraction of the on-orbit vehicle mass required by the auxiliary propulsion system of this Shuttle 2 vehicle using this technology is estimated to be 12.0 percent compared to 19.9 percent for a vehicle with an earth-storable bipropellant system. This results in a vehicle with the capability of delivering an additional 7820 kg to the Space Station.

Chemical Laser Solid Fuels Program

DTIC Science & Technology

1976-12-01

liquids. Solid propellant gas generators which can supply all of the ^(Tl-*fs DD , FORM w73 JAN 71 I"* EDITION OF 1 NOV SS IS OBSOLETE...seven tests, the mean weight yield was 13.24 ± 0.09 percent which is 97.72 percent of the theoretical weight yield of 13. SS percent for this...early in the test and peaks as the deuteriun flow rate is dropping at the burnout of the grain. The pressure differential across the filter discs

Aviation Turbine Fuels from Tar Sands Bitumen and Heavy Oils. Part 2. Laboratory Sample Production.

DTIC Science & Technology

1987-07-01

tar sand bitumen from West Central Kentucky; and Sunnyside tar sand bitumen from the Uinta Basin , Utah. Each of the feedstocks had unique...fuel and about 50 volume percent heavy gas oil (600-1000°F). The Westken bitumen was overall the heaviest of the four feedstocks evaluated. K factors...was 40 weight percent and about 20 weight percent in the total crude. 3. San Ardo Heavy oil The San Ardo field is located in the Coastal basin of the

Effects of spaceflight on the spermatogonial population of rat seminiferous epithelium

NASA Technical Reports Server (NTRS)

Sapp, Walter J.; Philpott, Delbert E.; Williams, Carol S.; Kato, Katharine; Stevenson, Joann; Vasquez, M.; Serova, L. V.

1990-01-01

Testes from rats flown on Cosmos 1887 were compared with vivarium control and synchronous control samples. The mean weights of flight testes, normalized for weight per 100 g, were 6.4 percent less when compared with the vivarium controls. Counts of spermatogonia from tissue sections (seminiferous tubules in maturation stage 6) from five animals in each group revealed 4 percent fewer spermatogonia in flight testes compared with synchronous controls and 11 percent fewer spermatogonia in flight samples compared with vivarium controls.

Boron containing multilayer coatings and method of fabrication

DOEpatents

Makowiecki, D.M.; Jankowski, A.F.

1997-09-23

Hard coatings are fabricated from multilayer boron/boron carbide, boron carbide/cubic boron nitride, and boron/boron nitride/boron carbide, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron and boron carbide used in forming the multilayers are formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/boron carbide, and boron carbide/cubic boron nitride is produced by depositing alternate layers of boron, cubic boron nitride or boron carbide, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be of a discrete or a blended or graded composition. 6 figs.

Boron containing multilayer coatings and method of fabrication

DOEpatents

Makowiecki, Daniel M.; Jankowski, Alan F.

1997-01-01

Hard coatings are fabricated from multilayer boron/boron carbide, boron carbide/cubic boron nitride, and boron/boron nitride/boron carbide, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron and boron carbide used in forming the multilayers are formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/boron carbide, and boron carbide/cubic boron nitride is produced by depositing alternate layers of boron, cubic boron nitride or boron carbide, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be of a discrete or a blended or graded composition.

Burning characteristics and fiber retention of graphite/resin matrix composites

NASA Technical Reports Server (NTRS)

Bowles, K. J.

1980-01-01

Graphite fiber reinforced resin matrix composites were subjected to controlled burning conditions to determine their burning characteristics and fiber retention properties. Small samples were burned with a natural gas fired torch to study the effects of fiber orientation and structural flaws such as holes and slits that were machined into the laminates. Larger laminate samples were burned in a modified heat release rate calorimeter. Unidirectional epoxy/graphite and polyimide/graphite composites and boron powder filled samples of each of the two composite systems were burn tested. The composites were exposed to a thermal radiation of 5.3 Btu/sq ft-sec in air. Samples of each of the unfilled composite were decomposed anaerobically in the calorimeter. Weight loss data were recorded for burning and decomposition times up to thirty-five minutes. The effects of fiber orientation, flaws, and boron filler additives to the resins were evaluated. A high char forming polyimide resin was no more effective in retaining graphite fibers than a low char forming epoxy resin when burned in air. Boron powder additions to both the polyimide and the epoxy resins stabilized the chars and effectively controlled the fiber release.

Pyrolytic boron nitride coatings on ceramic yarns and fabrication of insulations

NASA Technical Reports Server (NTRS)

Moore, Arthur W.

1992-01-01

Pyrolytic boron nitride (PBN) was deposited on Nicalon NL 202 silicon carbide yarns at 1000 to 1200 C with the goal of improving the resistance of the Nicalon to deterioration in an aerodynamic environment at temperatures up to 1000 C. For continuous coating, the yarns were fed through the deposition chamber of a pilot plant sized CVD furnace at a rate of about 2 feet per minute. PBN coatings were obtained by reacting boron trichloride and ammonia gases inside the deposition chamber. Most of the PBN coatings were made at around 1080 C to minimize thermal degradation of the Nicalon. Pressures were typically below 0.1 Torr. The coated yarns were characterized by weight per unit length, tensile strength and modulus, scanning electron microscopy, and scanning Auger microscopy. The PBN coated Nicalon was woven into cloth, but was not entirely satisfactory as a high temperature sizing. Several 13 in. square pieces of Nicalon cloth were coated with PBN in a batch process in a factory sized deposition furnace. Samples of cloth made from the PBN coated Nicalon were sewn into thermal insulation panels, whose performance is being compared with that of panels made using uncoated Nicalon.

The development of heterogeneous materials based on Ni and B4C powders using a cold spray and stratified selective laser melting technologies

NASA Astrophysics Data System (ADS)

Filippov, A. A.; Fomin, V. M.; Buzyurkin, A. E.; Kosarev, V. F.; Malikov, A. G.; Orishich, A. M.; Ryashin, N. S.

2018-01-01

The work is dedicated to the creation of new ceramic-composite materials based on boron carbide, nickel and using a laser welding in order to obtain three dimensional objects henceforth. The perspective way of obtaining which has been suggested by the authors combined two methods: cold spray technology and subsequent laser post-treatment. At this stage, the authors focused on the interaction of the laser with the substance, regardless of the multi-layer object development. The investigated material of this work was the metal-ceramic mixture based on boron carbide, which has high physical and mechanical characteristics, such as hardness, elastic modulus, and chemical resistance. The nickel powder as a binder and different types of boron carbide were used. The ceramic content varied from 30 to 70% by mass. Thin ceramic layers were obtained by the combined method and cross-sections of different seams were studied. It was shown that the most perspective layers for additive manufacturing could be obtained from cold spray coatings with ceramic concentrations more than 50% by weight treated when laser beam was defocused (thermal-conductive laser mode).

Microstructural observations in rapidly-solidified and heat-treated Ni3Al-Cr alloys

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

Carro, G.; Flanagan, W.F.

1992-08-01

The microstructural development following heat treatments of several rapidly-solidified Ni3Al-Cr and Ni3Al-Cr-B alloys is presented. Depending on composition, the as-solidified samples were either 100 percent gamma-prime phase - in the form of fine antiphase domains (APD) - or a mixture of gamma-prime (APDs) and beta phases. Upon annealing, the as-solidified microstructures transform to either APD-free gamma-prime or mixtures of gamma and gamma-prime phases. For those compositions where the quenched microstructures were 100 percent gamma-prime it was observed that APD coarsening followed conventional grain-growth kinetics, but when gamma phase precipitated on the APD boundaries the rate constant changed abruptly while themore » time exponent remained unaffected. It was also found that alloys containing critical amounts of chromium and boron are susceptible to precipitation of the boride Cr5B3. 14 refs.« less

Microstructural observations in rapidly-solidified and heat-treated Ni3Al-Cr alloys

NASA Technical Reports Server (NTRS)

Carro, G.; Flanagan, W. F.

1992-01-01

The microstructural development following heat treatments of several rapidly-solidified Ni3Al-Cr and Ni3Al-Cr-B alloys is presented. Depending on composition, the as-solidified samples were either 100 percent gamma-prime phase - in the form of fine antiphase domains (APD) - or a mixture of gamma-prime (APDs) and beta phases. Upon annealing, the as-solidified microstructures transform to either APD-free gamma-prime or mixtures of gamma and gamma-prime phases. For those compositions where the quenched microstructures were 100 percent gamma-prime it was observed that APD coarsening followed conventional grain-growth kinetics, but when gamma phase precipitated on the APD boundaries the rate constant changed abruptly while the time exponent remained unaffected. It was also found that alloys containing critical amounts of chromium and boron are susceptible to precipitation of the boride Cr5B3.

Weight outcomes audit for 34,271 adults referred to a primary care/commercial weight management partnership scheme.

PubMed

Stubbs, R James; Pallister, Carolyn; Whybrow, Stephen; Avery, Amanda; Lavin, Jacquie

2011-01-01

This project audited rate and extent of weight loss in a primary care/commercial weight management organisation partnership scheme. 34,271 patients were referred to Slimming World for 12 weekly sessions. Data were analysed using individual weekly weight records. Average (SD) BMI change was -1.5 kg/m² (1.3), weight change -4.0 kg (3.7), percent weight change -4.0% (3.6), rate of weight change -0.3 kg/week, and number of sessions attended 8.9 (3.6) of 12. For patients attending at least 10 of 12 sessions (n = 19,907 or 58.1%), average (SD) BMI change was -2.0 kg/m² (1.3), weight change -5.5 kg (3.8), percent weight change -5.5% (3.5), rate of weight change -0.4 kg/week, and average number of sessions attended was 11.5 (0.7) (p < 0.001, compared to all patients). Weight loss was greater in men (n = 3,651) than in women (n = 30,620) (p < 0.001). 35.8% of all patients enrolled and 54.7% in patients attending 10 or more sessions achieved at least 5% weight loss. Weight gain was prevented in 92.1% of all patients referred. Attendance explained 29.6% and percent weight lost in week 1 explained 18.4% of the variance in weight loss. Referral to a commercial organisation is a practical option for National Health Service (NHS) weight management strategies, which achieves clinically safe and effective weight loss. Copyright © 2011 S. Karger AG, Basel.

Use of fluorine-18-BPA PET images and image registration to enhance radiation treatment planning for boron neutron capture therapy

NASA Astrophysics Data System (ADS)

Khan, Mohammad Khurram

The Monte-Carlo based simulation environment for radiation therapy (SERA) software is used to simulate the dose administered to a patient undergoing boron neutron capture therapy (BNCT). Point sampling of tumor tissue results in an estimate of a uniform boron concentration scaling factor of 3.5. Under conventional treatment protocols, this factor is used to scale the boron component of the dose linearly and homogenously within the tumor and target volumes. The average dose to the tumor cells by such a method could be improved by better methods of quantifying the in-vivo 10B biodistribution. A better method includes radiolabeling para-Boronophenylalanine (p-BPA) with 18F and imaging the pharmaceutical using positron emission tomography (PET). This biodistribution of 18F-BPA can then be used to better predict the average dose delivered to the tumor regions. This work uses registered 18F-BPA PET images to incorporate the in-vivo boron biodistribution within current treatment planning. The registered 18F-BPA PET images are then coupled in a new computer software, PET2MRI.m, to linearly scale the boron component of the dose. A qualititative and quantitative assessment of the dose contours is presented using the two approaches. Tumor volume, tumor axial extent, and target locations are compared between using MRI or PET images to define the tumor volume. In addition, peak-to-normal brain value at tumor axial center is determined for pre and post surgery patients using 18F-BPA PET images. The differences noted between the registered GBM tumor volumes (range: 34.04--136.36%), tumor axial extent (range: 20--150%), and the beam target location (1.27--4.29 cm) are significantly different. The peak-to-normal brain values are also determined at the tumor axial center using the 18F-BPA PET images. The peak-to-normal brain values using the last frame of the pre-surgery study for the GBM patients ranged from 2.05--3.4. For post surgery time weighted PET data, the peak-to-normal brain value in the residual parts of the tumor ranged from 1.5--1.7. Qualitatively, boron dose contours are greatly shifted using PET images when compared with MRI images. Collectively, these differences can lead to significant reorientation of the beam and can significantly impact current BNCT treatment planning.

Full core analysis of IRIS reactor by using MCNPX.

PubMed

Amin, E A; Bashter, I I; Hassan, Nabil M; Mustafa, S S

2016-07-01

This paper describes neutronic analysis for fresh fuelled IRIS (International Reactor Innovative and Secure) reactor by MCNPX code. The analysis included criticality calculations, radial power and axial power distribution, nuclear peaking factor and axial offset percent at the beginning of fuel cycle. The effective multiplication factor obtained by MCNPX code is compared with previous calculations by HELIOS/NESTLE, CASMO/SIMULATE, modified CORD-2 nodal calculations and SAS2H/KENO-V code systems. It is found that k-eff value obtained by MCNPX is closer to CORD-2 value. The radial and axial powers are compared with other published results carried out using SAS2H/KENO-V code. Moreover, the WIMS-D5 code is used for studying the effect of enriched boron in form of ZrB2 on the effective multiplication factor (K-eff) of the fuel pin. In this part of calculation, K-eff is calculated at different concentrations of Boron-10 in mg/cm at different stages of burnup of unit cell. The results of this part are compared with published results performed by HELIOS code. Copyright © 2016 Elsevier Ltd. All rights reserved.

77 FR 69381 - Designation of Product Categories for Federal Procurement

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-19

... carbon in the product as a percent of the weight (mass) of the total organic carbon in the finished... fertilizer formulas that will improve the efficiency and the effectiveness of the chemicals, including... qualifying biobased carbon in the product as a percent of the weight (mass) of the total organic carbon in...

21 CFR 160.110 - Frozen eggs.

Code of Federal Regulations, 2013 CFR

2013-04-01

... or in a water carrier, but the amount added does not exceed 0.5 percent of the weight of the frozen eggs. If a water carrier is used, it shall contain not less than 50 percent by weight of such... paragraph (b) of this section is used, the label shall bear the statement “Monosodium phosphate (or...

21 CFR 160.110 - Frozen eggs.

Code of Federal Regulations, 2012 CFR

2012-04-01

... or in a water carrier, but the amount added does not exceed 0.5 percent of the weight of the frozen eggs. If a water carrier is used, it shall contain not less than 50 percent by weight of such... paragraph (b) of this section is used, the label shall bear the statement “Monosodium phosphate (or...

21 CFR 160.110 - Frozen eggs.

Code of Federal Regulations, 2014 CFR

2014-04-01

... or in a water carrier, but the amount added does not exceed 0.5 percent of the weight of the frozen eggs. If a water carrier is used, it shall contain not less than 50 percent by weight of such... paragraph (b) of this section is used, the label shall bear the statement “Monosodium phosphate (or...

40 CFR Table 4 to Subpart Ffff of... - Emission Limits for Storage Tanks

Code of Federal Regulations, 2010 CFR

2010-07-01

... HAP emissions by ≥95 percent by weight or to ≤20 ppmv of TOC or organic HAP and ≤20 ppmv of hydrogen... ≥95 percent by weight or to ≤20 ppmv of TOC or organic HAP and ≤20 ppmv of hydrogen halide and halogen...

40 CFR 60.562-1 - Standards: Process emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... methane and ethane) (TOC) by 98 weight percent, or to a concentration of 20 parts per million by volume (ppmv) on a dry basis, whichever is less stringent. The TOC is expressed as the sum of the actual... Polypropylene and Polyethylene Affected Facilities Procedure /a/ Applicable TOC weight percent range Control/no...

More About High-Temperature Resistance Strain Gauges

NASA Technical Reports Server (NTRS)

Englund, D. R.; Williams, W. D.; Lei, Jih-Fen; Hulse, C. O.

1994-01-01

Two reports present additional information on electrical-resistance strain gauges described in "High-Temperature Resistance Strain Gauges" (LEW-15379). For protection against oxidation at high temperatures, gauges covered, by flame spraying, with coats of alumina containing up to 1 weight percent of yttria or, perferably, containing 4 to 6 weight percent of zirconia.

7 CFR 52.1845 - Sizes of seedless raisins.

Code of Federal Regulations, 2012 CFR

2012-01-01

... raisins will pass through round perforations 22/64-inch in diameter, but not more than 10 percent, by weight, of all the raisins may pass through round perforations 20/64-inch in diameter. (b) Small or midget size raisins means that 95 percent, by weight, of all the raisins will pass through round...

40 CFR 52.1689 - Original Identification of plan section.

Code of Federal Regulations, 2014 CFR

2014-07-01

... percent, by weight, for the Long Island Lighting Co.'s Northport Generating Facility (Units 1, 2, and 3... oil limitation to 1.0 percent, by weight, for the Long Island Lighting Company's Glenwood Generating... of New York, Inc. Arthur Kill generating facility, units 2 and 3, Staten Island, New York and...

40 CFR 52.1689 - Original Identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

... percent, by weight, for the Long Island Lighting Co.'s Northport Generating Facility (Units 1, 2, and 3... oil limitation to 1.0 percent, by weight, for the Long Island Lighting Company's Glenwood Generating... of New York, Inc. Arthur Kill generating facility, units 2 and 3, Staten Island, New York and...

40 CFR 52.1689 - Original identification of plan section.

Code of Federal Regulations, 2012 CFR

2012-07-01

... percent, by weight, for the Long Island Lighting Co.'s Northport Generating Facility (Units 1, 2, and 3... oil limitation to 1.0 percent, by weight, for the Long Island Lighting Company's Glenwood Generating... of New York, Inc. Arthur Kill generating facility, units 2 and 3, Staten Island, New York and...

External fuel vaporization study, phase 2

NASA Technical Reports Server (NTRS)

Szetela, E. J.; Chiappetta, L.

1981-01-01

An analytical study was conducted to evaluate the effect of variations in fuel properties on the design of an external fuel vaporizaton system. The fuel properties that were considered included thermal stability, critical temperature, enthalpy a critical conditions, volatility, and viscosity. The design parameters that were evaluated included vaporizer weight and the impact on engine requirement such as maintenance, transient response, performance, and altitude relight. The baseline fuel properties were those of Jet A. The variation in thermal stability was taken as the thermal stability variation for Experimental Referee Broad Specification (ERBS) fuel. The results of the analysis indicate that a change in thermal stability equivalent to that of ERBS would increase the vaporization system weight by 20 percent, decrease oprating time between cleaning by 40 percent and make altitude relight more difficult. An increase in fuel critical temperature of 39 K would require a 40 percent increase in vaporization system weight. The assumed increase in enthalpy and volatility would also increase vaporizer weight by 40 percent and make altitude relight extremely difficult. The variation in fuel viscosity would have a negligible effect on the design parameters.

Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)

USGS Publications Warehouse

Coplen, Tyler B.; Shrestha, Yesha

2016-01-01

There are 63 chemical elements that have two or more isotopes that are used to determine their standard atomic weights. The isotopic abundances and atomic weights of these elements can vary in normal materials due to physical and chemical fractionation processes (not due to radioactive decay). These variations are well known for 12 elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine, and thallium), and the standard atomic weight of each of these elements is given by IUPAC as an interval with lower and upper bounds. Graphical plots of selected materials and compounds of each of these elements have been published previously. Herein and at the URL http://dx.doi.org/10.5066/F7GF0RN2, we provide isotopic abundances, isotope-delta values, and atomic weights for each of the upper and lower bounds of these materials and compounds.

Mapping variations in weight percent silica measured from multispectral thermal infrared imagery - Examples from the Hiller Mountains, Nevada, USA and Tres Virgenes-La Reforma, Baja California Sur, Mexico

USGS Publications Warehouse

Hook, S.J.; Dmochowski, J.E.; Howard, K.A.; Rowan, L.C.; Karlstrom, K.E.; Stock, J.M.

2005-01-01

Remotely sensed multispectral thermal infrared (8-13 ??m) images are increasingly being used to map variations in surface silicate mineralogy. These studies utilize the shift to longer wavelengths in the main spectral feature in minerals in this wavelength region (reststrahlen band) as the mineralogy changes from felsic to mafic. An approach is described for determining the amount of this shift and then using the shift with a reference curve, derived from laboratory data, to remotely determine the weight percent SiO2 of the surface. The approach has broad applicability to many study areas and can also be fine-tuned to give greater accuracy in a particular study area if field samples are available. The approach was assessed using airborne multispectral thermal infrared images from the Hiller Mountains, Nevada, USA and the Tres Virgenes-La Reforma, Baja California Sur, Mexico. Results indicate the general approach slightly overestimates the weight percent SiO2 of low silica rocks (e.g. basalt) and underestimates the weight percent SiO2 of high silica rocks (e.g. granite). Fine tuning the general approach with measurements from field samples provided good results for both areas with errors in the recovered weight percent SiO2 of a few percent. The map units identified by these techniques and traditional mapping at the Hiller Mountains demonstrate the continuity of the crystalline rocks from the Hiller Mountains southward to the White Hills supporting the idea that these ranges represent an essentially continuous footwall block below a regional detachment. Results from the Baja California data verify the most recent volcanism to be basaltic-andesite. ?? 2005 Elsevier Inc. All rights reserved.

Combined oral contraceptives and body weight: do oral contraceptives cause weight gain? A primate model.

PubMed

Edelman, A; Jensen, J T; Bulechowsky, M; Cameron, J

2011-02-01

The aim of this study was to determine if oral contraceptive (OC) use affects body weight, body composition and metabolism in primates. Reproductive-age female rhesus monkeys of normal and obese BMI were studied to document baseline weight stability, then treated continuously with an OC (dosed to achieve equivalent human serum levels for a 30 µg ethinyl estradiol/150 µg levonorgestrel preparation) for 237 days. Monkeys were monitored for changes in body weight, levels of physical activity (measured by a triaxial Actical accelerometer), food/caloric intake, percent body fat (dual energy X-ray absorptiometry, DEXA) and metabolism (24 h metabolic rate and serum metabolic substrate and hormone concentrations). All 10 monkeys completed the study protocol with no adverse events. While body weight (-0.73% change) and percent body fat (-1.78% change) of the normal BMI group did not significantly decrease from baseline, obese monkeys showed a significant decrease in body weight (-8.58% change, P < 0.01) and percent body fat (-12.13% change P = 0.02) with OC treatment. In both the obese (P = 0.03) and the normal BMI (P = 0.01) groups, there was a significant increase in basal metabolic rate with OC use. No changes were seen in food intake, activity level or % lean muscle mass with OC use for either BMI-based group. Overall, OC use appears to cause a slight increase in basal metabolic rate in female monkeys, leading to a decrease in body weight and percent body fat in obese individuals.

Ceramic impregnated superabrasives

DOEpatents

Radtke, Robert P.; Sherman, Andrew

2009-02-10

A superabrasive fracture resistant compact is formed by depositing successive layers of ceramic throughout the network of open pores in a thermally stable self-bonded polycrystalline diamond or cubic boron nitride preform. The void volume in the preform is from approximately 2 to 10 percent of the volume of the preform, and the average pore size is below approximately 3000 nanometers. The preform is evacuated and infiltrated under at least about 1500 pounds per square inch pressure with a liquid pre-ceramic polymerizable precursor. The precursor is infiltrated into the preform at or below the boiling point of the precursor. The precursor is polymerized into a solid phase material. The excess is removed from the outside of the preform, and the polymer is pyrolized to form a ceramic. The process is repeated at least once more so as to achieve upwards of 90 percent filling of the original void volume. When the remaining void volume drops below about 1 percent the physical properties of the compact, such as fracture resistance, improve substantially. Multiple infiltration cycles result in the deposition of sufficient ceramic to reduce the void volume to below 0.5 percent. The fracture resistance of the compacts in which the pores are lined with formed in situ ceramic is generally at least one and one-half times that of the starting preforms.

A low-carbohydrate as compared with a low-fat diet in severe obesity.

PubMed

Samaha, Frederick F; Iqbal, Nayyar; Seshadri, Prakash; Chicano, Kathryn L; Daily, Denise A; McGrory, Joyce; Williams, Terrence; Williams, Monica; Gracely, Edward J; Stern, Linda

2003-05-22

The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed. We randomly assigned 132 severely obese subjects (including 77 blacks and 23 women) with a mean body-mass index of 43 and a high prevalence of diabetes (39 percent) or the metabolic syndrome (43 percent) to a carbohydrate-restricted (low-carbohydrate) diet or a calorie- and fat-restricted (low-fat) diet. Seventy-nine subjects completed the six-month study. An analysis including all subjects, with the last observation carried forward for those who dropped out, showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet (mean [+/-SD], -5.8+/-8.6 kg vs. -1.9+/-4.2 kg; P=0.002) and had greater decreases in triglyceride levels (mean, -20+/-43 percent vs. -4+/-31 percent; P=0.001), irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications. Insulin sensitivity, measured only in subjects without diabetes, also improved more among subjects on the low-carbohydrate diet (6+/-9 percent vs. -3+/-8 percent, P=0.01). The amount of weight lost (P<0.001) and assignment to the low-carbohydrate diet (P=0.01) were independent predictors of improvement in triglyceride levels and insulin sensitivity. Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost. This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study. Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed. Copyright 2003 Massachusetts Medical Society

Methods of forming boron nitride

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

Trowbridge, Tammy L; Wertsching, Alan K; Pinhero, Patrick J

A method of forming a boron nitride. The method comprises contacting a metal article with a monomeric boron-nitrogen compound and converting the monomeric boron-nitrogen compound to a boron nitride. The boron nitride is formed on the same or a different metal article. The monomeric boron-nitrogen compound is borazine, cycloborazane, trimethylcycloborazane, polyborazylene, B-vinylborazine, poly(B-vinylborazine), or combinations thereof. The monomeric boron-nitrogen compound is polymerized to form the boron nitride by exposure to a temperature greater than approximately 100.degree. C. The boron nitride is amorphous boron nitride, hexagonal boron nitride, rhombohedral boron nitride, turbostratic boron nitride, wurzite boron nitride, combinations thereof, or boronmore » nitride and carbon. A method of conditioning a ballistic weapon and a metal article coated with the monomeric boron-nitrogen compound are also disclosed.« less

Weight change and physical function in older women: findings from the Nun Study.

PubMed

Tully, C L; Snowdon, D A

1995-12-01

To investigate the association between change in weight and decline in physical function in older women. Longitudinal study of a defined population of Catholic sisters (nuns) whose weight and function were assessed twice, an average of 584 days apart. Unique life communities (convents) located throughout the United States. 475 Catholic sisters who were 75 to 99 years of age (M = 82.1, SD = 4.8) and were independent in at least one Activity of Daily Living (ADL) at the first assessment of weight and function. None. At each assessment, weight, ADLs, and cognitive function were evaluated as part of the Nun Study--a longitudinal study of aging and Alzheimer's disease. Annual percent weight change was calculated using weights from the two assessments, as well as the number of days that elapsed between assessments. Mean weight at first assessment was 140 pounds (range 78 to 232, SD = 27). The mean annual percent weight change was 0.1% (range 22% loss to 16% gain, SD = 3.8). Age- and initial weight-adjusted findings indicated that those participants with an annual percent weight loss of 3% or greater had 2.7 to 3.9 times the risk of becoming dependent in each ADL, compared to the sisters with no weight change. The elevated risk persisted in those who were mentally intact or were independent in their eating habits. Monitoring of weight may be an easy and inexpensive method of identifying older individuals at increased risk of disability.

Describing patterns of weight changes using principal components analysis: results from the Action for Health in Diabetes (Look AHEAD) research group.

PubMed

Espeland, Mark A; Bray, George A; Neiberg, Rebecca; Rejeski, W Jack; Knowler, William C; Lang, Wei; Cheskin, Lawrence J; Williamson, Don; Lewis, C Beth; Wing, Rena

2009-10-01

To demonstrate how principal components analysis can be used to describe patterns of weight changes in response to an intensive lifestyle intervention. Principal components analysis was applied to monthly percent weight changes measured on 2,485 individuals enrolled in the lifestyle arm of the Action for Health in Diabetes (Look AHEAD) clinical trial. These individuals were 45 to 75 years of age, with type 2 diabetes and body mass indices greater than 25 kg/m(2). Associations between baseline characteristics and weight loss patterns were described using analyses of variance. Three components collectively accounted for 97.0% of total intrasubject variance: a gradually decelerating weight loss (88.8%), early versus late weight loss (6.6%), and a mid-year trough (1.6%). In agreement with previous reports, each of the baseline characteristics we examined had statistically significant relationships with weight loss patterns. As examples, males tended to have a steeper trajectory of percent weight loss and to lose weight more quickly than women. Individuals with higher hemoglobin A(1c) (glycosylated hemoglobin; HbA(1c)) tended to have a flatter trajectory of percent weight loss and to have mid-year troughs in weight loss compared to those with lower HbA(1c). Principal components analysis provided a coherent description of characteristic patterns of weight changes and is a useful vehicle for identifying their correlates and potentially for predicting weight control outcomes.

Commingling effect of gynoid and android fat patterns on cardiometabolic dysregulation in normal weight American adults.

PubMed

Okosun, I S; Seale, J P; Lyn, R

2015-05-18

To determine the independent and commingling effect of android and gynoid percent fat (measured using Dual Energy X-Ray Absorptiometry) on cardiometabolic dysregulation in normal weight American adults. The 2005-2006 data (n=1802) from the United States National Health and Nutritional Examination Surveys (NHANES) were used in this study. Associations of android percent fat, gynoid percent fat and their joint occurrence with risks of cardiometabolic risk factors were estimated using prevalence odds ratios from logistic regression analyses. Android-gynoid percent fat ratio was more highly correlated with cardiometabolic dysregulation than android percent fat, gynoid percent fat or body mass index. Commingling of android and gynoid adiposities was associated with much greater odds of cardiometabolic risk factors than either android or gynoid adiposities. Commingling of android and gynoid adiposities was associated with 1.75 (95% confidence interval (CI)=1.42-2.93), 1.48 (95% CI=1.32-1.91), 1.61 (95% CI=1.50-1.89), 3.56 (95% CI=2.91-4.11) and 1.86 (95% CI=1.49-1.96) increased odds of elevated glucose, elevated blood pressure, elevated low-density lipoprotein-cholesterol, elevated triglyceride and low high-density lipoprotein-cholesterol, respectively. Normal weight subjects who present with both android and gynoid adiposities should be advised of the associated health risks. Both android and gynoid fat accumulations should be considered in developing public health strategies for reducing cardiometabolic disease risk in normal weight subjects.

Design and operation of the national home health aide survey: 2007-2008.

PubMed

Bercovitz, Anita; Moss, Abigail J; Sengupta, Manisha; Harris-Kojetin, Lauren D; Squillace, Marie R; Emily, Rosenoff; Branden, Laura

2010-03-01

This report provides an overview of the National Home Health Aide Survey (NHHAS), the first national probability survey of home health aides. NHHAS was designed to provide national estimates of home health aides who provided assistance in activities of daily living (ADLs) and were directly employed by agencies that provide home health and/or hospice care. This report discusses the need for and objectives of the survey, the design process, the survey methods, and data availability. METHODS NHHAS, a multistage probability sample survey, was conducted as a supplement to the 2007 National Home and Hospice Care Survey (NHHCS). Agencies providing home health and/or hospice care were sampled, and then aides employed by these agencies were sampled and interviewed by telephone. Survey topics included recruitment, training, job history, family life, client relations, work-related injuries, and demographics. NHHAS was virtually identical to the 2004 National Nursing Assistant Survey of certified nursing assistants employed in sampled nursing homes with minor changes to account for differences in workplace environment and responsibilities. RESULTS From September 2007 to April 2008, interviews were completed with 3,416 aides. A public-use data file that contains the interview responses, sampling weights, and design variables is available. The NHHAS overall response rate weighted by the inverse of the probability of selection was 41 percent. This rate is the product of the weighted first-stage agency response rate of 57 percent (i.e., weighted response rate of 59 percent for agency participation in NHHCS times the weighted response rate of 97 percent for agencies participating in NHHCS that also participated in NHHAS) and the weighted second-stage aide response rate of 72 percent to NHHAS.

Subcutaneous fat loss is greater than visceral fat loss with diet and exercise, weight-loss promoting drugs and bariatric surgery: a critical review and meta-analysis.

PubMed

Merlotti, C; Ceriani, V; Morabito, A; Pontiroli, A E

2017-05-01

Aim of this review is to compare visceral and subcutaneous fat loss with all available strategies (diet and exercise, weight-loss promoting agents and bariatric surgery). Eighty-nine studies, all full papers, were analyzed to evaluate visceral and subcutaneous fat changes, measured through ultrasound, computerized tomography, magnetic resonance imaging and expressed as thickness, weight, area and volume. Studies were included in a meta-analysis (random-effects model). Intervention effect (absolute and percent changes of visceral and subcutaneous fat) was expressed as standardized mean differences, with 95% confidence intervals. Publication bias was formally assessed. The result was that subcutaneous fat was greater than visceral fat when measured as area, volume and weight, not as thickness; decrease of subcutaneous fat was greater than visceral fat when measured as area, volume and weight, not as thickness; percent decrease of visceral fat was always greater than percent decrease of subcutaneous fat, with no differences between different strategies. No intervention preferentially targets visceral fat. Basal visceral fat depots are smaller than basal subcutaneous fat depots. Visceral fat loss is linked to subcutaneous fat loss. With all strategies, percent decrease of visceral fat prevails on subcutaneous fat loss.

Status of groundwater quality in the Santa Barbara Study Unit, 2011: California GAMA Priority Basin Project

USGS Publications Warehouse

Davis, Tracy A.; Kulongoski, Justin T.

2016-10-03

Groundwater quality in the 48-square-mile Santa Barbara study unit was investigated in 2011 as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. The study unit is mostly in Santa Barbara County and is in the Transverse and Selected Peninsular Ranges hydrogeologic province. The GAMA Priority Basin Project is carried out by the U.S. Geological Survey in collaboration with the California State Water Resources Control Board and Lawrence Livermore National Laboratory.The GAMA Priority Basin Project was designed to provide a statistically unbiased, spatially distributed assessment of the quality of untreated groundwater in the primary aquifer system of California. The primary aquifer system is defined as that part of the aquifer corresponding to the perforation interval of wells listed in the California Department of Public Health database for the Santa Barbara study unit. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifer system of the Santa Barbara study unit, not the treated drinking water delivered to consumers by water purveyors.The status assessment for the Santa Barbara study unit was based on water-quality and ancillary data collected in 2011 by the U.S. Geological Survey from 23 sites and on water-quality data from the California Department of Public Health database for January 24, 2008–January 23, 2011. The data used for the assessment included volatile organic compounds; pesticides; pharmaceutical compounds; two constituents of special interest, perchlorate and N-nitrosodimethylamine (NDMA); and naturally present inorganic constituents, such as major ions and trace elements. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used to evaluate groundwater quality for those constituents that have federal or California regulatory and non-regulatory benchmarks for drinking-water quality. For inorganic, organic, and special-interest constituents, a relative-concentration greater than 1.0 indicates a concentration greater than the benchmark and is classified as high. Inorganic constituents are classified as moderate if relative-concentrations are greater than 0.5 and less than or equal to 1.0 and are classified as low if relative-concentrations are less than or equal to 0.5. For organic and special-interest constituents, the boundary between moderate and low relative-concentrations was set at 0.1.Aquifer-scale proportion was used as the primary metric for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the areal percentage of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents. Moderate and low aquifer-scale proportions were defined as the areal percentage of the primary aquifer system that had moderate and low relative-concentrations, respectively. Two statistical approaches—grid based and spatially weighted—were used to calculate aquifer-scale proportions for individual constituents and constituent classes. Grid-based and spatially weighted estimates were comparable in this the study (within 90-percent confidence intervals). Grid-based results were selected for use in the status assessment unless, as was observed in a few cases, a grid-based result was zero and the spatially weighted result was not zero, in which case, the spatially weighted result was used.Inorganic constituents that have human-health benchmarks were present at high relative-concentrations in 5.3 percent of the primary aquifer system and at moderate concentrations in 32 percent. High aquifer-scale proportions of inorganic constituents primarily were a result of high aquifer-scale proportions of boron (5.3 percent) and fluoride (5.3 percent). Inorganic constituents that have aesthetic-based benchmarks, referred to as secondary maximum contaminant levels, were present at high relative-concentrations in 58 percent of the primary aquifer system and at moderate concentrations in 37 percent. Iron, manganese, sulfate, and total dissolved solids were the inorganic constituents with secondary maximum contaminant levels present at high relative-concentrations.In contrast, organic and special-interest constituents that have health-based benchmarks were not detected at high relative-concentrations in the primary aquifer system. Of the 218 organic constituents analyzed, 10 were detected—9 that had human-health benchmarks. Organic constituents were present at moderate relative-concentrations in 11 percent of the primary aquifer system. The moderate aquifer-scale proportions were a result of moderate relative-concentrations of the volatile organic compounds methyl tert-butyl ether (MTBE, 11 percent) and 1,2-dichloroethane (5.6 percent). The volatile organic compounds 1,1,1-trichloroethane, 1,1-dichloroethane, bromodichloromethane, chloroform, MTBE, and perchloroethene (PCE); the pesticide simazine; and the special-interest constituent perchlorate were detected at more than 10 percent of the sites in the Santa Barbara study unit. Perchlorate was present at moderate relative-concentrations in 50 percent of the primary aquifer system. Pharmaceutical compounds and NDMA were not detected in the Santa Barbara study unit.

Design synthesis and optimization of joined-wing transports

NASA Technical Reports Server (NTRS)

Gallman, John W.; Smith, Stephen C.; Kroo, Ilan M.

1990-01-01

A computer program for aircraft synthesis using a numerical optimizer was developed to study the application of the joined-wing configuration to transport aircraft. The structural design algorithm included the effects of secondary bending moments to investigate the possibility of tail buckling and to design joined wings resistant to buckling. The structural weight computed using this method was combined with a statistically-based method to obtain realistic estimates of total lifting surface weight and aircraft empty weight. A variety of 'optimum' joined-wing and conventional aircraft designs were compared on the basis of direct operating cost, gross weight, and cruise drag. The most promising joined-wing designs were found to have a joint location at about 70 percent of the wing semispan. The optimum joined-wing transport is shown to save 1.7 percent in direct operating cost and 11 percent in drag for a 2000 nautical mile transport mission.

Photosynthesis and Biomass Allocation in Oak Seedlings Grown Under Shade

Treesearch

Shi-Jean S. Sung; Paul P. Kormanik; Stanley J. Zarnoch

1998-01-01

Abstract-Northern red oak (Quercus rubra L.) (NRO) and white oak (Q. alba L.) (WO) acorns were sown into wooden plots and grown under 30 percent shade screen (30 percent S) or 70 percent shade screen (70 percent S). Seedlings grown under full sun were the controls (C). At the end of the first year, the 30 percent S NRO had 30 percent greater seedling dry weight (DW...

40 CFR Table 27 to Subpart Uuu of... - Continuous Compliance With Inorganic HAP Emission Limits for Catalytic Reforming Units

Code of Federal Regulations, 2011 CFR

2011-07-01

... percent by weight or to a concentration of 30 ppmv (dry basis), corrected to 3 percent oxygen. Maintaining...), corrected to 3 percent oxygen. 2. Each existing cyclic or continuous catalytic reforming unit Reduce... to 3 percent oxygen Maintaining a 97 percent HCl control efficiency or an HCl concentration no more...

40 CFR Table 27 to Subpart Uuu of... - Continuous Compliance With Inorganic HAP Emission Limits for Catalytic Reforming Units

Code of Federal Regulations, 2010 CFR

2010-07-01

... percent by weight or to a concentration of 30 ppmv (dry basis), corrected to 3 percent oxygen. Maintaining...), corrected to 3 percent oxygen. 2. Each existing cyclic or continuous catalytic reforming unit Reduce... to 3 percent oxygen Maintaining a 97 percent HCl control efficiency or an HCl concentration no more...

75 FR 55741 - Honey From Argentina: Notice of Extension of Time Limit for Preliminary Results and Partial...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-14

... Naturales-Natural Foods, Alma Pura, Bomare S.A., Compania Apicola Argentina S.A., El Mana S.A., Interrupcion... products covered are natural honey, artificial honey containing more than 50 percent natural honey by weight, preparations of natural honey containing more than 50 percent natural honey by weight, and...

40 CFR Table 2 to Subpart Eeee of... - Emission Limits

Code of Federal Regulations, 2010 CFR

2010-07-01

... emissions of total organic HAP (or, upon approval, TOC) by at least 95 weight-percent or, as an option, to... organic HAP (or, upon approval, TOC) by at least 95 weight-percent or, as an option, to an exhaust... total organic HAP (or, upon approval, TOC) from the loading of organic liquids either by venting the...

40 CFR Table 8 to Subpart Dddd of... - Continuous Compliance With the Work Practice Requirements

Code of Federal Regulations, 2012 CFR

2012-07-01

... with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate with... inlet furnish moisture content at less than or equal to 30 percent (by weight, dry basis) AND... records of the inlet temperature of furnish moisture content and inlet dryer temperature. (2) Hardwood...

40 CFR Table 8 to Subpart Dddd of... - Continuous Compliance With the Work Practice Requirements

Code of Federal Regulations, 2014 CFR

2014-07-01

... with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate with... inlet furnish moisture content at less than or equal to 30 percent (by weight, dry basis) AND... records of the inlet temperature of furnish moisture content and inlet dryer temperature. (2) Hardwood...

40 CFR Table 8 to Subpart Dddd of... - Continuous Compliance With the Work Practice Requirements

Code of Federal Regulations, 2013 CFR

2013-07-01

... with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate with... inlet furnish moisture content at less than or equal to 30 percent (by weight, dry basis) AND... records of the inlet temperature of furnish moisture content and inlet dryer temperature. (2) Hardwood...

Trauma-Induced Weight Loss and Cognitive Deficits among Former Prisoners of War.

ERIC Educational Resources Information Center

Sutker, Patricia B.; And Others

1990-01-01

Compared former prisoners of war (POWs) reporting confinement weight losses greater than 35 percent (N=60), less than 35 percent (N=113), and non-POW combat veterans (N=50) on Wechsler Adult Intelligence Scale-Revised and Wechsler Memory Scale Logical Memory indices. Findings suggest that severe POW confinement stress reflected by trauma-induced…

Neutron and gamma radiation shielding material, structure, and process of making structure

DOEpatents

Hondorp, Hugh L.

1984-01-01

The present invention is directed to a novel neutron and gamma radiation elding material consisting of 95 to 97 percent by weight SiO.sub.2 and 5 to 3 percent by weight sodium silicate. In addition, the method of using this composition to provide a continuous neutron and gamma radiation shielding structure is disclosed.

7 CFR 51.2284 - Size classification.

Code of Federal Regulations, 2010 CFR

2010-01-01

...: “Halves”, “Pieces and Halves”, “Pieces” or “Small Pieces”. The size of portions of kernels in the lot... consists of 85 percent or more, by weight, half kernels, and the remainder three-fourths half kernels. (See § 51.2285.) (b) Pieces and halves. Lot consists of 20 percent or more, by weight, half kernels, and the...

77 FR 52265 - Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... total area of corrosion or thread damage, or both, covers less than 25 percent of the length of the... paragraph (d)(3) of this AD. (B) If the total area of corrosion or thread damage, or both, covers 25 percent... to require inspections for corrosion or thread damage to each tail rotor balance weight (weight) and...

Crystalline boron nitride aerogels

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

Zettl, Alexander K.; Rousseas, Michael; Goldstein, Anna P.

This disclosure provides methods and materials related to boron nitride aerogels. For example, one aspect relates to a method for making an aerogel comprising boron nitride, comprising: (a) providing boron oxide and an aerogel comprising carbon; (b) heating the boron oxide to melt the boron oxide and heating the aerogel; (c) mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide; and (d) converting at least a portion of the carbon to boron nitride to obtain the aerogel comprising boron nitride. Another aspect relates to a method for making an aerogel comprising boron nitride, comprising heating boron oxidemore » and an aerogel comprising carbon under flow of a nitrogen-containing gas, wherein boron oxide vapor and the nitrogen-containing gas convert at least a portion of the carbon to boron nitride to obtain the aerogel comprising boron nitride.« less

Qualification of M256 Breechblock Repair Procedure

DTIC Science & Technology

1994-03-01

Percent) Element Chemistry Carbon 0.30/0.40 Silicon 0.15/0.35 Manganese 0.40/0.70 Phosphorus 0.015 max Sulfur 0.015 max Aluminum 0.0 15 max Chromium 1.00...Weld Filler Metal, AWS A&28 Class ER120S.1 (Weight Percent) Element Chemistry Carbon 0.07 Silicon 0.35 Sulfur 0.0008 Phosphorus 0.0006 Chromium 0.45...14OS-l) (Weight Percent) Element Chemistry Carbon 0.11 Silicon 0.35 Sulfur 0.0008 Phosphorus 0.0005 Chromium 0.70 Nickel 2.60 Molybdenum 0.90 Manganese

Elevated Temperature Properties of Titanium Carbide Base Ceramals Containing Nickel or Iron

NASA Technical Reports Server (NTRS)

Cooper, A L; Colteryahn, L E

1951-01-01

Elevated-temperature properties of titanium carbide base ceramals containing nickel or iron were determined in oxidation, modulus of rupture, tensile strength, and thermal-shock resistance. These materials followed the general growth law and exhibited two stages in oxidation. The following tensile strengths were found at 2000 degrees F: 13.3 weight percent nickel, 16, 150 pounds per square inch; 11.8 weight percent iron, 12,500 pounds per square inch; unalloyed titanium carbide, 16,450 pounds per square inch. Nickel or iron additions to titanium carbide improved the thermal-shock resistance, nickel more. The path of fracture in tensile and thermal-shock specimens was found to progress approximately 50 percent intergranularly and 50 percent transgranularly.

Strategic Analysis of the 2014 Wounded Warrior Project Annual Alumni Survey: A Way Forward

DTIC Science & Technology

2015-01-01

77 percent); back, neck, or shoulder problems (73 percent); depression (69 percent); anxiety (65 percent); tinnitus (56 percent); knee injuries or...percent); tinnitus (56 percent); knee injury or problem (52 percent); and migraine or other severe headache (50 percent). We did not weight the...of the Total Number of Respondents TBI 9,049 42.9 43.2 Tinnitus 11,745 55.7 54.5 Other severe physical injury 3,740 17.8 17.8 Other severe mental

21 CFR 573.750 - Pichia pastoris dried yeast.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the following percent-by-weight specifications: (1) Crude protein, not less than 60 percent. (2) Crude fat, not less than 2 percent. (3) Crude fiber, not more than 2 percent. (4) Ash, not more than 13... pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

21 CFR 573.750 - Pichia pastoris dried yeast.

Code of Federal Regulations, 2011 CFR

2011-04-01

... the following percent-by-weight specifications: (1) Crude protein, not less than 60 percent. (2) Crude fat, not less than 2 percent. (3) Crude fiber, not more than 2 percent. (4) Ash, not more than 13... pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

21 CFR 573.750 - Pichia pastoris dried yeast.

Code of Federal Regulations, 2012 CFR

2012-04-01

... the following percent-by-weight specifications: (1) Crude protein, not less than 60 percent. (2) Crude fat, not less than 2 percent. (3) Crude fiber, not more than 2 percent. (4) Ash, not more than 13... pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

21 CFR 573.750 - Pichia pastoris dried yeast.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the following percent-by-weight specifications: (1) Crude protein, not less than 60 percent. (2) Crude fat, not less than 2 percent. (3) Crude fiber, not more than 2 percent. (4) Ash, not more than 13... pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

21 CFR 573.750 - Pichia pastoris dried yeast.

Code of Federal Regulations, 2013 CFR

2013-04-01

... the following percent-by-weight specifications: (1) Crude protein, not less than 60 percent. (2) Crude fat, not less than 2 percent. (3) Crude fiber, not more than 2 percent. (4) Ash, not more than 13... pastoris dried yeast may be used in feed formulations of broiler chickens as a source of protein not to...

Label Identification from Statistical Tabulation (LIST) temporal extendability study. [North Dakota, South Dakota, and Minnesota

NASA Technical Reports Server (NTRS)

Dennis, T. B. (Principal Investigator)

1980-01-01

The author has identified the following significant results. The most apparent contributors to the problem of poor temporal extension of LIST are the drastic changes in the brightness keys and an inadequate set of AI responses in Phase 3. The brightness trajectories change drastically from Phase 3 to the transition year (TY). Removing brightness channels from the discriminant does not completely correct the lack of extendability. Removing brightness increases the accuracy of the extension from Phase 3 to TY from 57.7 percent to 64.18 percent. The removal of the Al keys increases accuracy to 65.76 percent. Although the latter increase appears insignificant when compared to the first, the removal of only the Al keys increased accuracy to 63.58 percent. Proper weighting of the responses explains 73.8 percent of the ground truth labels but only 56.7 percent of the Al labels. By contrast, the TY responses which were weighted to explain the TY ground truth labels fared equally well, explaining 73.6 percent of those labels and 87.1 percent of the Al labels.

Structure and reactivity of boron-ate complexes derived from primary and secondary boronic esters.

PubMed

Feeney, Kathryn; Berionni, Guillaume; Mayr, Herbert; Aggarwal, Varinder K

2015-06-05

Boron-ate complexes derived from primary and secondary boronic esters and aryllithiums have been isolated, and the kinetics of their reactions with carbenium ions studied. The second-order rate constants have been used to derive nucleophilicity parameters for the boron-ate complexes, revealing that nucleophilicity increased with (i) electron-donating aromatics on boron, (ii) neopentyl glycol over pinacol boronic esters, and (iii) 12-crown-4 ether.

High explosive compound

DOEpatents

Crawford, Theodore C.

1976-01-01

1. A low detonation velocity explosive consisting essentially of a particulate mixture of ortho-boric acid and trinitrotoluene, said mixture containing from about 25 percent to about 65 percent by weight of ortho-boric acid, said ortho-boric acid comprised of from 60 percent to 90 percent of spherical particles having a mean particle size of about 275 microns and 10 percent to 40 percent of spherical particles having a particle size less than about 44 microns.

Histomorphometric study of alveolar bone healing in rats fed a boron-deficient diet.

PubMed

Gorustovich, Alejandro A; Steimetz, Tammy; Nielsen, Forrest H; Guglielmotti, María B

2008-04-01

Bone healing after tooth extraction in rats is a suitable experimental model to study bone formation. Thus, we performed a study to determine the effects of boron (B) deficiency on bone healing by using this model. The first lower right molar of weanling Wistar rats was extracted under anesthesia. The animals were divided into two groups: +B (adequate; 3 mg B/kg diet), and -B (boron-deficient; 0.07 mg/kg diet). The animals in both groups were killed in groups of 10 at 7 and 14 days after surgery. The guidelines of the NIH for the care and use of laboratory animals were observed. The mandibles were resected, fixed, decalcified, and embedded in paraffin. Buccolingually oriented sections were obtained at the level of the mesial alveolus and used for histometric evaluations. Total alveolar volume (TAV) and trabecular bone volume per total volume (BV/TV) in the apical third of the alveolus were determined. Percentages of osteoblast surface (ObS), eroded surface (ES), and quiescent surface (QS) were determined. No statistical significant differences in food intake and body weight were observed. Histomorphometric evaluation found -B rats had 36% and 63% reductions in BV/TV at 7 and 14 days, respectively. When compared with +B rats, -B rats had significant reductions (57% and 87%) in ObS concomitantly with increases (120% and 126%) in QS at 7 and 14 days, respectively. The findings show that boron deficiency results in altered bone healing because of a marked reduction in osteogenesis. 2008 Wiley-Liss, Inc

78 FR 51143 - Aluminum Extrusions From the People's Republic of China: Initiation of Changed Circumstances...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-20

... the major alloying element, with manganese accounting for not more than 3.0 percent of total materials... magnesium accounting for at least 0.1 percent but not more than 2.0 percent of total materials by weight, and silicon accounting for at least 0.1 percent but not more than 3.0 percent of total materials by...

21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Code of Federal Regulations, 2014 CFR

2014-04-01

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

Corrosion rates of fasteners in treated wood exposed to 100% relative humidity

Treesearch

Samuel L. Zelinka; Douglas R. Rammer

2009-01-01

In the past, gravimetric corrosion data for fasteners exposed to treated wood has been reported as a percent weight loss. Although percent weight loss is a valid measure of corrosion for comparing identical fasteners, it can distort the corrosion performance of fasteners with different geometries and densities. This report reevaluates a key report on the corrosiveness...

77 FR 38299 - Agency Information Collection Activities; Submission for Office of Management and Budget Review...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-27

... 0910-New) I. Background A recent study of obesity indicates that 35.5 percent of men and 35.8 percent... were spent in 2008 to treat obesity-related diseases (Ref. 2). Studies have shown that weight loss can significantly reduce the burden of obesity-related comorbidities (Refs. 3 and 4), and that weight lost as a...

7 CFR 52.1858 - Grades of mixed types or varieties of raisins.

Code of Federal Regulations, 2013 CFR

2013-01-01

... moisture, in accordance with this subpart. Mixed types of processed raisins of U.S. Grade A, U.S. Grade B, or U.S. Grade C may contain not more than 18 percent, by weight, of moisture. Mixed types of processed raisins that as a mixture exceed 18 percent, by weight, of moisture are “Substandard.” ...

40 CFR Table 6 to Subpart Dddd of... - Initial Compliance Demonstrations for Work Practice Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... moisture content less than or equal to 30 percent (by weight, dry basis) AND operate with an inlet dryer... dryer” AND you have a record of the inlet moisture content and inlet dryer temperature (as required in... an inlet moisture content of less than or equal to 25 percent (by weight, dry basis) You meet the...

40 CFR Table 6 to Subpart Dddd of... - Initial Compliance Demonstrations for Work Practice Requirements

Code of Federal Regulations, 2011 CFR

2011-07-01

... moisture content less than or equal to 30 percent (by weight, dry basis) AND operate with an inlet dryer... dryer” AND you have a record of the inlet moisture content and inlet dryer temperature (as required in... an inlet moisture content of less than or equal to 25 percent (by weight, dry basis) You meet the...

7 CFR 52.1858 - Grades of mixed types or varieties of raisins.

Code of Federal Regulations, 2014 CFR

2014-01-01

... moisture, in accordance with this subpart. Mixed types of processed raisins of U.S. Grade A, U.S. Grade B, or U.S. Grade C may contain not more than 18 percent, by weight, of moisture. Mixed types of processed raisins that as a mixture exceed 18 percent, by weight, of moisture are “Substandard.” ...

Commingling effect of gynoid and android fat patterns on cardiometabolic dysregulation in normal weight American adults

PubMed Central

Okosun, I S; Seale, J P; Lyn, R

2015-01-01

Aim: To determine the independent and commingling effect of android and gynoid percent fat (measured using Dual Energy X-Ray Absorptiometry) on cardiometabolic dysregulation in normal weight American adults. Methods: The 2005–2006 data (n=1802) from the United States National Health and Nutritional Examination Surveys (NHANES) were used in this study. Associations of android percent fat, gynoid percent fat and their joint occurrence with risks of cardiometabolic risk factors were estimated using prevalence odds ratios from logistic regression analyses. Results: Android-gynoid percent fat ratio was more highly correlated with cardiometabolic dysregulation than android percent fat, gynoid percent fat or body mass index. Commingling of android and gynoid adiposities was associated with much greater odds of cardiometabolic risk factors than either android or gynoid adiposities. Commingling of android and gynoid adiposities was associated with 1.75 (95% confidence interval (CI)=1.42–2.93), 1.48 (95% CI=1.32–1.91), 1.61 (95% CI=1.50–1.89), 3.56 (95% CI=2.91–4.11) and 1.86 (95% CI=1.49–1.96) increased odds of elevated glucose, elevated blood pressure, elevated low-density lipoprotein-cholesterol, elevated triglyceride and low high-density lipoprotein-cholesterol, respectively. Conclusions: Normal weight subjects who present with both android and gynoid adiposities should be advised of the associated health risks. Both android and gynoid fat accumulations should be considered in developing public health strategies for reducing cardiometabolic disease risk in normal weight subjects. PMID:25985091

Groundwater quality in the Western San Joaquin Valley study unit, 2010: California GAMA Priority Basin Project

USGS Publications Warehouse

Fram, Miranda S.

2017-06-09

Water quality in groundwater resources used for public drinking-water supply in the Western San Joaquin Valley (WSJV) was investigated by the USGS in cooperation with the California State Water Resources Control Board (SWRCB) as part of its Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. The WSJV includes two study areas: the Delta–Mendota and Westside subbasins of the San Joaquin Valley groundwater basin. Study objectives for the WSJV study unit included two assessment types: (1) a status assessment yielding quantitative estimates of the current (2010) status of groundwater quality in the groundwater resources used for public drinking water, and (2) an evaluation of natural and anthropogenic factors that could be affecting the groundwater quality. The assessments characterized the quality of untreated groundwater, not the quality of treated drinking water delivered to consumers by water distributors.The status assessment was based on data collected from 43 wells sampled by the U.S. Geological Survey for the GAMA Priority Basin Project (USGS-GAMA) in 2010 and data compiled in the SWRCB Division of Drinking Water (SWRCB-DDW) database for 74 additional public-supply wells sampled for regulatory compliance purposes between 2007 and 2010. To provide context, concentrations of constituents measured in groundwater were compared to U.S. Environmental Protection Agency (EPA) and SWRCB-DDW regulatory and non-regulatory benchmarks for drinking-water quality. The status assessment used a spatially weighted, grid-based method to estimate the proportion of the groundwater resources used for public drinking water that has concentrations for particular constituents or class of constituents approaching or above benchmark concentrations. This method provides statistically unbiased results at the study-area scale within the WSJV study unit, and permits comparison of the two study areas to other areas assessed by the GAMA Priority Basin Project statewide.Groundwater resources used for public drinking water in the WSJV study unit are among the most saline and most affected by high concentrations of inorganic constituents of all groundwater resources used for public drinking water that have been assessed by the GAMA Priority Basin Project statewide. Among the 82 GAMA Priority Basin Project study areas statewide, the Delta–Mendota study area ranked above the 90th percentile for aquifer-scale proportions of groundwater resources having concentrations of total dissolved solids (TDS), sulfate, chloride, manganese, boron, chromium(VI), selenium, and strontium above benchmarks, and the Westside study area ranked above the 90th percentile for TDS, sulfate, manganese, and boron.In the WSJV study unit as a whole, one or more inorganic constituents with regulatory or non-regulatory, health-based benchmarks were present at concentrations above benchmarks in about 53 percent of the groundwater resources used for public drinking water, and one or more organic constituents with regulatory health-based benchmarks were detected at concentrations above benchmarks in about 3 percent of the resource. Individual constituents present at concentrations greater than health-based benchmarks in greater than 2 percent of groundwater resources used for public drinking water included: boron (51 percent, SWRCB-DDW notification level), chromium(VI) (25 percent, SWRCB-DDW maximum contaminant level (MCL)), arsenic (10 percent, EPA MCL), strontium (5.1 percent, EPA Lifetime health advisory level (HAL)), nitrate (3.9 percent, EPA MCL), molybdenum (3.8 percent, EPA HAL), selenium (2.6 percent, EPA MCL), and benzene (2.6 percent, SWRCB-DDW MCL). In addition, 50 percent of the resource had TDS concentrations greater than non-regulatory, aesthetic-based SWRCB-DDW upper secondary maximum contaminant level (SMCL), and 44 percent had manganese concentrations greater than the SWRCB-DDW SMCL.Natural and anthropogenic factors that could affect the groundwater quality were evaluated by using results from statistical testing of associations between constituent concentrations and values of potential explanatory factors, inferences from geochemical and age-dating tracer results, and by considering the water-quality results in the context of the hydrogeologic setting of the WSJV study unit.Natural factors, particularly the lithologies of the source areas for groundwater recharge and of the aquifers, were the dominant factors affecting groundwater quality in most of the WSJV study unit. However, where groundwater resources used for public supply included groundwater recharged in the modern era, mobilization of constituents by recharge of water used for irrigation also affected groundwater quality. Public-supply wells in the Westside study area had a median depth of 305 m and primarily tapped groundwater recharged hundreds to thousands of years ago, whereas public-supply wells in the Delta–Mendota study area had a median depth of 85 m and primarily tapped either groundwater recharged within the last 60 years or groundwater consisting of mixtures of this modern recharge and older recharge.Public-supply wells in the WSJV study unit are screened in the Tulare Formation and zones above and below the Corcoran Clay Member are used. The Tulare Formation primarily consists of alluvial sediments derived from the Coast Ranges to the west, except along the valley trough at the eastern margin of the WSJV study unit where the Tulare Formation consists of fluvial sands derived from the Sierra Nevada to the east. Groundwater from wells screened in the Sierra Nevada sands had manganese-reducing or manganese- and iron-reducing oxidation-reduction (redox) conditions. These redox conditions commonly were associated with elevated arsenic or molybdenum concentrations, and the dominance of arsenic(III) in the dissolved arsenic supports reductive dissolution of iron and manganese oxyhydroxides as the mechanism. In addition, groundwater from many wells screened in Sierra Nevada sands contained low concentrations of nitrite or ammonium, indicating reduction of nitrate by denitrification or dissimilatory processes, respectively.Geology of the Coast Ranges westward of the study unit strongly affects groundwater quality in the WSJV. Elevated concentrations of TDS, sulfate, boron, selenium and strontium in groundwater were primarily associated with aquifer sediments and recharge derived from areas of the Coast Ranges dominated by Cretaceous-to-Miocene age, organic-rich, reduced marine shales, known as the source of selenium in WSJV soils, surface water, and groundwater. Low sulfur-isotopic values (δ34S) of dissolved sulfate indicate that the sulfate was largely derived from oxidation of biogenic pyrite from the shales, and correlations with trace element concentrations, geologic setting, and groundwater geochemical modeling indicated that distributions of sulfate, strontium, and selenium in groundwater were controlled by dissolution of secondary sulfate minerals in soils and sediments.Elevated concentrations of chromium(VI) were primarily associated with aquifer sediments and recharge derived from areas of the Coast Ranges dominated by the Franciscan Complex and ultramafic rocks. The Franciscan Complex also has boron-rich, sodium-chloride dominated hydrothermal fluids that contribute to elevated concentrations of boron and TDS.Groundwater from wells screened in Coast Ranges alluvium was primarily oxic and relatively alkaline (median pH value of 7.55) in the Delta–Mendota study area, and primarily nitrate-reducing or suboxic and alkaline (median pH value of 8.4) in the Westside study area. Many groundwater samples from those wells have elevated concentrations of arsenic(V), molybdenum, selenium, or chromium(VI), consistent with desorption of metal oxyanions from mineral surfaces under those geochemical conditions.High concentrations of benzene were associated with deep wells located in the vicinity of petroleum deposits at the southern end of the Westside study area. Groundwater from these wells had premodern age and anoxic geochemical conditions, and the ratios among concentrations of hydrocarbon constituents were different from ratios found in fuels and combustion products, which is consistent with a geogenic source for the benzene rather than contamination from anthropogenic sources.Water stable-isotope compositions, groundwater recharge temperatures, and groundwater ages were used to infer four types of groundwater: (1) groundwater derived from natural recharge of water from major rivers draining the Sierra Nevada; (2) groundwater primarily derived from natural recharge of water from Coast Ranges runoff; (3) groundwater derived from recharge of pumped groundwater applied to the land surface for irrigation; and (4) groundwater derived from recharge during a period of much cooler paleoclimate. Water previously used for irrigation was found both above and below the Corcoran Clay, supporting earlier inferences that this clay member is no longer a robust confining unit.Recharge of water used for irrigation has direct and indirect effects on groundwater quality. Elevated nitrate concentrations and detections of herbicides and fumigants in the Delta–Mendota study area generally were associated with greater agricultural land use near the well and with water recharged during the last 60 years. However, the extent of the groundwater resource affected by agricultural sources of nitrate was limited by groundwater redox conditions sufficient to reduce nitrate. The detection frequency of perchlorate in Delta–Mendota groundwater was greater than expected for natural conditions. Perchlorate, nitrate, selenium, and strontium concentrations were correlated with one another and were greater in groundwater inferred to be recharge of previously pumped groundwater used for irrigation. The source of the perchlorate, selenium, and strontium appears to be salts deposited in the soils and sediments of the arid WSJV that are dissolved and flushed into groundwater by the increased amount of recharge caused by irrigation. In the Delta–Mendota study area, the groundwater with elevated concentrations of selenium was found deeper in the aquifer system than it was reported by a previous study 25 years earlier, suggesting that this transient front of groundwater with elevated concentrations of constituents derived from dissolution of soil salts by irrigation recharge is moving down through the aquifer system and is now reaching the depth zone used for public drinking water supply.

Gas chromatographic simulated distillation-mass spectrometry for the determination of the boiling point distributions of crude oils

PubMed

Roussis; Fitzgerald

2000-04-01

The coupling of gas chromatographic simulated distillation with mass spectrometry for the determination of the distillation profiles of crude oils is reported. The method provides the boiling point distributions of both weight and volume percent amounts. The weight percent distribution is obtained from the measured total ion current signal. The total ion current signal is converted to weight percent amount by calibration with a reference crude oil of a known distillation profile. Knowledge of the chemical composition of the crude oil across the boiling range permits the determination of the volume percent distribution. The long-term repeatability is equivalent to or better than the short-term repeatability of the currently available American Society for Testing and Materials (ASTM) gas chromatographic method for simulated distillation. Results obtained by the mass spectrometric method are in very good agreement with results obtained by conventional methods of physical distillation. The compositional information supplied by the method can be used to extensively characterize crude oils.

Electroextraction of boron from boron carbide scrap

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

Jain, Ashish; Anthonysamy, S., E-mail: sas@igcar.gov.in; Ghosh, C.

2013-10-15

Studies were carried out to extract elemental boron from boron carbide scrap. The physicochemical nature of boron obtained through this process was examined by characterizing its chemical purity, specific surface area, size distribution of particles and X-ray crystallite size. The microstructural characteristics of the extracted boron powder were analyzed by using scanning electron microscopy and transmission electron microscopy. Raman spectroscopic examination of boron powder was also carried out to determine its crystalline form. Oxygen and carbon were found to be the major impurities in boron. Boron powder of purity ∼ 92 wt. % could be produced by the electroextraction processmore » developed in this study. Optimized method could be used for the recovery of enriched boron ({sup 10}B > 20 at. %) from boron carbide scrap generated during the production of boron carbide. - Highlights: • Recovery of {sup 10}B from nuclear grade boron carbide scrap • Development of process flow sheet • Physicochemical characterization of electroextracted boron • Microscopic examination of electroextracted boron.« less

JAGUAR Procedures for Detonation Behavior of Explosives Containing Boron

NASA Astrophysics Data System (ADS)

Stiel, Leonard; Baker, Ernest; Capellos, Christos

2009-06-01

The JAGUAR product library was expanded to include boron and boron containing products. Relationships of the Murnaghan form for molar volumes and derived properties were implemented in JAGUAR. Available Hugoniot and static volumertic data were analyzed to obtain constants of the Murnaghan relationship for solid boron, boron oxide, boron nitride, boron carbide, and boric acid. Experimental melting points were also utilized with optimization procedures to obtain the constants of the volumetric relationships for liquid boron and boron oxide. Detonation velocities for HMX - boron mixtures calculated with these relationships using JAGUAR are in closer agreement with literature values at high initial densities for inert (unreacted) boron than with the completely reacted metal. These results indicate that boron mixtures may exhibit eigenvalue detonation behavior, as observed by aluminized combined effects explosives, with higher detonation velocities than would be achieved by a classical Chapman-Jouguet detonation. Analyses of calorimetric measurements for RDX - boron mixtures indicate that at high boron contents the formation of side products, including boron nitride and boron carbide, inhibits the energy output obtained from the detonation of the formulation.

Growth and device processing of hexagonal boron nitride epilayers for thermal neutron and deep ultraviolet detectors

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

Doan, T. C.; Li, J.; Lin, J. Y.

2016-07-15

Solid-state neutron detectors with high performance are highly sought after for the detection of fissile materials. However, direct-conversion neutron detectors based on semiconductors with a measureable efficiency have not been realized. We report here the first successful demonstration of a direct-conversion semiconductor neutron detector with an overall detection efficiency for thermal neutrons of 4% and a charge collection efficiency as high as 83%. The detector is based on a 2.7 μm thick {sup 10}B-enriched hexagonal boron nitride (h-BN) epitaxial layer. The results represent a significant step towards the realization of practical neutron detectors based on h-BN epilayers. Neutron detectors basedmore » on h-BN are expected to possess all the advantages of semiconductor devices including wafer-scale processing, compact size, light weight, and ability to integrate with other functional devices.« less

Tin-silver-bismuth solders for electronics assembly

DOEpatents

Vianco, Paul T.; Rejent, Jerome A.

1995-01-01

A lead-free solder alloy for electronic assemblies composed of a eutectic alloy of tin and silver with a bismuth addition, x, of 0

Tin-silver-bismuth solders for electronics assembly

DOEpatents

Vianco, P.T.; Rejent, J.A.

1995-08-08

A lead-free solder alloy is disclosed for electronic assemblies composed of a eutectic alloy of tin and silver with a bismuth addition, x, of 0

Thermodynamics and kinetics of pack aluminide coating formation on IN-100

NASA Technical Reports Server (NTRS)

Levine, S. R.; Caves, R. M.

1973-01-01

An investigation of the effects of pack variables on the formation of aluminide coatings on nickel-base superalloy IN-100 was conducted. Also, the thermodynamics and kinetics of coating formation were analyzed. Observed coating weights were in good agreement with predictions made from the analysis. Pack temperature rather than pack aluminum activity controls the principal coating phase formed. In 1 weight percent aluminum packs, aluminum weight gains were related to the halide pack activator. Solid-state nickel diffusion controlled coating formation from sodium fluoride and chloride and ammonium fluoride activated packs. In other ammonium and sodium halide activated 1 weight percent aluminum packs, gaseous diffusion controlled coating formation.

Noni-based nutritional supplementation and exercise interventions influence body composition

PubMed Central

Palu, Afa K.; West, Brett J.; Jensen, Jarakae

2011-01-01

Background: The prevalence of obesity and overweight in the Unites States has reached unprecedented levels, and so has the need for effective exercise and nutritional programs for prevention of unhealthy weight gain or safe weight loss. Aims: The present study was conducted in overweight men and women to assess the impact of noni-based nutritional supplementation and exercise interventions on body composition. Materials and Methods: Twenty two participants (16 women and 6 men), ages 18-65, were enrolled in a 12-week, open-label trial of a weight-loss program involving noni-based dietary supplements, gender-specific daily calorie restriction, and exercise interventions. Weight, percent body fat, and body mass index were measured before and after the trial. Results: All participants experienced weight loss. The average decrease in fat mass was highly significant (P < 0.0001), as were decreases in percent body fat and body mass index. Individual weight and fat mass losses were 17.55 ± 9.73 and 21.78 ± 8.34 lbs., respectively, and individual percent body fat and body mass index decreases were 8.91 ± 3.58 % and 2.6 ± 1.32, respectively. Conclusion: The nutritional and exercise interventions significantly influenced body composition among participants. PMID:22363077

Noni-based nutritional supplementation and exercise interventions influence body composition.

PubMed

Palu, Afa K; West, Brett J; Jensen, Jarakae

2011-12-01

The prevalence of obesity and overweight in the Unites States has reached unprecedented levels, and so has the need for effective exercise and nutritional programs for prevention of unhealthy weight gain or safe weight loss. The present study was conducted in overweight men and women to assess the impact of noni-based nutritional supplementation and exercise interventions on body composition. Twenty two participants (16 women and 6 men), ages 18-65, were enrolled in a 12-week, open-label trial of a weight-loss program involving noni-based dietary supplements, gender-specific daily calorie restriction, and exercise interventions. Weight, percent body fat, and body mass index were measured before and after the trial. All participants experienced weight loss. The average decrease in fat mass was highly significant (P < 0.0001), as were decreases in percent body fat and body mass index. Individual weight and fat mass losses were 17.55 ± 9.73 and 21.78 ± 8.34 lbs., respectively, and individual percent body fat and body mass index decreases were 8.91 ± 3.58 % and 2.6 ± 1.32, respectively. The nutritional and exercise interventions significantly influenced body composition among participants.

Nevada Kids Count Data Book, 1997.

ERIC Educational Resources Information Center

We Can, Inc., Las Vegas, NV.

This Kids Count data book is the first to examine statewide indicators of the well being of Nevada's children. The statistical portrait is based on 15 indicators of child well being: (1) percent low birth-weight babies; (2) infant mortality rate; (3) percent of children in poverty; (4) percent of children in single-parent families; (5) percent of…

Process for microwave sintering boron carbide

DOEpatents

Holcombe, C.E.; Morrow, M.S.

1993-10-12

A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

Process for microwave sintering boron carbide

DOEpatents

Holcombe, Cressie E.; Morrow, Marvin S.

1993-01-01

A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

Development of low-chromium, chromium-tungsten steels for fusion

NASA Astrophysics Data System (ADS)

Klueh, R. L.; Alexander, D. J.; Kenik, E. A.

1995-12-01

High-chromium (9-12% Cr) CrMo and CrW ferritic steels are favored as candidates for fusion applications. In early work to develop reduced-activation steels, an Fe2.25Cr2W-0.25V-O.1C steel (designated 2.25Cr-2WV) had better strength than an Fe9Cr2W-0.25V-0.07Tra-0.1C (9Cr-2WVTa) steel (compositions are in weight percent). However, the 2.25Cr-2WV had poor impact properties, as determined by the ductile-brittle transition temperature and upper-shelf energy of subsize Charpy impact specimens. Because low-chromium steels have some advantages over high-chromium steels, a program to develop low-chromium steels is in progress. Microstructural analysis indicated that the reason for the inferior impact toughness of the 2.25Cr-2WV was the granular bainite obtained when the steel was normalized. Properties can be improved by developing an acicular bainite microstructure by increasing the cooling rate after austenitization. Alternatively, acicular bainite can be promoted by increasing the hardenability. Hardenability was changed by adding small amounts of boron and additional chromium to the 2.250-2WV composition. A combination of B, Cr, and Ta additions resulted in low-chromium reduced-activation steels with mechanical properties comparable to those of 9Cr-2WVTa.

Report on the CCT Supplementary Comparison S1 of Infrared Spectral Normal Emittance/Emissivity

PubMed Central

Hanssen, Leonard; Wilthan, B.; Monte, Christian; Hollandt, Jörg; Hameury, Jacques; Filtz, Jean-Remy; Girard, Ferruccio; Battuello, Mauro; Ishii, Juntaro

2016-01-01

The National Measurement Institutes (NMIs) of the United States, Germany, France, Italy and Japan, have joined in an inter-laboratory comparison of their infrared spectral emittance scales. This action is part of a series of supplementary inter-laboratory comparisons (including thermal conductivity and thermal diffusivity) sponsored by the Consultative Committee on Thermometry (CCT) Task Group on Thermophysical Quantities (TG-ThQ). The objective of this collaborative work is to strengthen the major operative National Measurement Institutes’ infrared spectral emittance scales and consequently the consistency of radiative properties measurements carried out worldwide. The comparison has been performed over a spectral range of 2 μm to 14 μm, and a temperature range from 23 °C to 800 °C. Artefacts included in the comparison are potential standards: oxidized inconel, boron nitride, and silicon carbide. The measurement instrumentation and techniques used for emittance scales are unique for each NMI, including the temperature ranges covered as well as the artefact sizes required. For example, all three common types of spectral instruments are represented: dispersive grating monochromator, Fourier transform and filter-based spectrometers. More than 2000 data points (combinations of material, wavelength and temperature) were compared. Ninety-eight percent (98%) of the data points were in agreement, with differences to weighted mean values less than the expanded uncertainties calculated from the individual NMI uncertainties and uncertainties related to the comparison process. PMID:28239193

Composition and method to remove asbestos

DOEpatents

Block, Jacob

1998-05-19

A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed, wherein the composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Composition and method to remove asbestos

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

Block, J.

A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Composition and method to remove asbestos

DOEpatents

Block, J.

1998-05-19

A composition for transforming a chrysotile asbestos-containing material into a non-asbestos material is disclosed. The composition comprises water, at least about 30% by weight of a boron tetrafluoride salt, free of or having only small amounts of an inorganic acid, an inorganic acid salt or a mixture thereof. A method of transforming the asbestos-containing material into a non-asbestos material using the present composition also is disclosed.

Program for establishing long time flight service performance of composite materials in the central wing structure of C-130 aircraft. Phase 2: Detailed design

NASA Technical Reports Server (NTRS)

Harvill, W. E.; Duhig, J. J.; Spencer, B. R.

1973-01-01

The design, fabrication, and evaluation of boron-epoxy reinforced C-130 center wing boxes are discussed. Design drawings, static strength, fatigue endurance, flutter, and weight analyses required for the wing box fabrication are presented. Additional component testing to verify the design for panel buckling and to evaluate specific local design areas are reported.

Status and understanding of groundwater quality in the South Coast Interior groundwater basins, 2008: California GAMA Priority Basin Project

USGS Publications Warehouse

Parsons, Mary C.; Kulongoski, Justin T.; Belitz, Kenneth

2014-01-01

Groundwater quality in the approximately 653-square-mile (1,691-square-kilometer) South Coast Interior Basins (SCI) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The South Coast Interior Basins study unit contains eight priority groundwater basins grouped into three study areas, Livermore, Gilroy, and Cuyama, in the Southern Coast Ranges hydrogeologic province. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA South Coast Interior Basins study was designed to provide a spatially unbiased assessment of untreated (raw) groundwater quality within the primary aquifer system, as well as a statistically consistent basis for comparing water quality between basins. The assessment was based on water-quality and ancillary data collected by the USGS from 50 wells in 2008 and on water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer system was defined by the depth intervals of the wells listed in the CDPH database for the SCI study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as trace elements and minor ions. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifer system of the SCI study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than 1.0 indicates a concentration greater than a benchmark, and a relative-concentration less than or equal to 1.0 indicates a concentration equal to or less than a benchmark. Relative-concentrations of organic constituents and special-interest constituents were classified as “high” (relative-concentration greater than 1.0), “moderate” (relative-concentration greater than 0.1 and less than or equal to 1.0), or “low” (relative-concentration less than or equal to 0.1). Relative-concentrations of inorganic constituents were classified as “high” (relative-concentration greater than 1.0), “moderate” (relative-concentration greater than 0.5 and less than or equal to 1.0), or “low” (relative-concentration less than or equal to 0.5). Aquifer-scale proportion was used as the primary metric in the status assessment for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the areal percentage of the primary aquifer system with moderate and low relative-concentrations, respectively. Two statistical approaches—grid-based and spatially weighted—were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. Grid-based and spatially weighted estimates were comparable in the SCI study unit (within 90-percent confidence intervals). Inorganic constituents (one or more) with health-based benchmarks were detected at high relative-concentrations in 29 percent of the primary aquifer system, at moderate relative-concentrations in 37 percent, and at low relative-concentrations in 34 percent. High aquifer-scale proportions of inorganic constituents primarily reflected high aquifer-scale proportions of nitrate (14 percent), boron (8.6 percent), molybdenum (8.6 percent), and arsenic (5.7 percent). In contrast, the relative-concentrations of organic constituents (one or more) were high in 1.6 percent, moderate in 2.0 percent, and low or not detected in 96 percent of the primary aquifer system. Of the 207 organic and special-interest constituents analyzed for, 15 constituents were detected. Perchlorate was found at moderate relative-concentrations in 34 percent of the aquifer. Two organic constituents were frequently detected (in greater than 10 percent of samples): the trihalomethane chloroform and the herbicide simazine. The second component of this study, the understanding assessment, identified natural and human factors that may have affected groundwater quality by evaluating land use, physical characteristics of the wells, and geochemical conditions of the aquifer. This evaluation was done by using statistical tests of correlations between these potential explanatory factors and water-quality data. Concentrations of arsenic, molybdenum, and manganese were generally greater in anoxic and pre-modern groundwater than other groundwater. In contrast, concentrations of nitrate and perchlorate were significantly higher in oxic and modern groundwater. Concentrations of simazine were greater in modern than pre-modern groundwater. Chloroform detections were positively correlated with greater urban land use. Boron concentrations and chloroform detections were higher in the Livermore study area than in the other study areas of the SCI; total dissolved solids and sulfate concentrations were greater in the Cuyama study area.

Preparation and Characterization of Ni Spines Grown on the Surface of Cubic Boron Nitride Grains by Electroplating Method

PubMed Central

Gui, Yanghai; Zhao, Jianbo; Chen, Jingbo; Jiang, Yuanli

2016-01-01

Cubic boron nitride (cBN) is widely applied in cutting and grinding tools. cBN grains plated by pure Ni and Ni/SiC composite were produced under the same conditions from an additive-free nickel Watts type bath. The processed electroplating products were characterized by the techniques of scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermoanalysis (TG-DTA). Due to the presence of SiC particles, there are some additional nodules on the surface of Ni/SiC plated cBN compared with the pure Ni plated cBN. The unique morphology of Ni/SiC plated cBN should attain greater retention force in resin bond. Moreover, the coating weight of cBN grains could be controlled by regulating the plating time. cBN grains with 60% coating weight possess the optimum grinding performance due to their roughest and spiniest surface. In addition, Ni spines plated cBN grains show good thermal stability when temperature is lower than 464 °C. Therefore, the plated cBN grains are more stable and suitable for making resin bond abrasive tools below 225 °C. Finally, the formation mechanism of electroplating products is also discussed. PMID:28773283

Flywheel containment technology assessment

NASA Astrophysics Data System (ADS)

Coppa, A. P.; Zweben, C. H.; Mirandy, L.

1980-07-01

The important effect of containment weight on the density of a flywheel was examined for a selection of flywheel designs incorporating metallic and composite construction as contained by steel housings. Three different flywheel constructions are presented, namely laminated rotor, shaped disk, and multirim. Materials are steel for the first two types and E glass, S glass and Kevlar composites for the third type. All of the flywheels were comparable in that their stress levels were based on long term high cycle operation. All of the specific energy values were penalized heavily by the containment weight, the least being the laminated rotor (-29 percent) and the greatest being the shaped disk (-72 percent). The penalties for the multirim designs are -45 percent (E glass), -55 percent (S glass), and -60 percent (Kevlar). The low penalty of the laminated steel rotor was due to the fact that the containment weight was based on withstanding the rupture of only one of the constituent disks. The high penalty of the shaped steel disk, on the other hand, reflects the severe containment action that resulted from its bursting into large, hard, and axially narrow fragments. The intermediate but nevertheless substantial containment penalty of the multidrum composite rotors resulted from their relatively mild containment behavior.

Tribo-mechanical properties of thin boron coatings deposited on polished cobalt alloy surfaces for orthopedic applications

PubMed Central

Klepper, C. C.; Williams, J. M.; Truhan, J.J.; Qu, J.; Riester, L.; Hazelton, R. C.; Moschella, J.J.; Blau, P.J.; Anderson, J.P.; Popoola, O.O.; Keitz, M.D.

2008-01-01

This paper presents experimental evidence that thin (<∼200 nm) boron coatings, deposited with a (vacuum) cathodic arc technique on pre-polished Co-Cr-Mo surfaces, could potentially extend the life of metal-on-polymer orthopedic devices using cast Co-Cr-Mo alloy for the metal component. The primary tribological test used a linear, reciprocating pin-on-disc arrangement, with pins made of ultra-high molecular weight polyethylene. The disks were cast Co-Cr-Mo samples that were metallographically polished and then coated with boron at a substrate bias of 500 V and at about 100 °C. The wear tests were carried out in a saline solution to simulate the biological environment. The improvements were manifested by the absence of a detectable wear track scar on the coated metal component, while significant polymer transfer film was detected on the uncoated (control) samples tested under the same conditions. The polymer transfer track was characterized with both profilometry and Rutherford Backscattering Spectroscopy. Mechanical characterization of the thin films included nano-indentation, as well as additional pin-on-disk tests with a steel ball to demonstrate adhesion, using ultra-high frequency acoustic microscopy to probe for any void occurrence at the coating-substrate interface. PMID:19340285

Carcass yield traits of kids from a complete diallel of Boer, Kiko, and Spanish meat goat breeds semi-intensively managed on humid subtropical pasture.

PubMed

Browning, R; Phelps, O; Chisley, C; Getz, W R; Hollis, T; Leite-Browning, M L

2012-03-01

Bucklings (n = 275) from a complete diallel of Boer, Kiko, and Spanish meat goats were slaughtered at 7 mo of age (4 mo postweaning) to evaluate genetic effects on carcass yield. Breed of sire did not affect (P > 0.05) live, carcass, and primal weights. Conversely, breed of dam was a consistently significant source of variation for carcass weight traits. Kiko dams produced kids with heavier (P < 0.05) live, carcass, and primal weights than Boer dams. Weights from Spanish dams were intermediate to Boer and Kiko with the significance of differences varying by trait. Cold carcass dressing percent was affected (P < 0.01) by breeds of sire and dam. Boer sires decreased (P < 0.05) dressing percent compared with Kiko and Spanish sires. Dressing percent was also less (P < 0.01) from Boer dams than from Kiko dams; Spanish dams were intermediate and did not differ (P > 0.05) from Boer or Kiko. Subjective conformation scores for muscularity were affected (P < 0.01) by breeds of sire and dam. Boer-sired kids had better (P < 0.01) live scores than Kiko-sired kids. Progeny of Boer dams had better (P < 0.05) live scores than progeny of Spanish dams. Boer-sired kids also had better carcass scores (P < 0.05) than Kiko-sired and Spanish-sired kids. Breed differences for primal cut proportions were negligible. Proportional boneless meat yields did not vary (P > 0.05) by breeds of sire or dam. Direct effects of Boer were negative for carcass weight, dressing percent, and shoulder weight and positive for proportional leg weight. Direct effects of Kiko were positive for carcass weight and shoulder weight and negative for proportional leg weight. Direct effects of Spanish did not differ (P > 0.10) from 0 for any trait tested. Heterosis levels were similar among breed pairings. Heterosis was substantial (P ≤ 0.05) for live, carcass, and primal weights (5 to 9%) but not for dressing percent, proportional boneless meat yield, or primal weight proportions (<2%). Significant genetic variation was observed among goat breeds for carcass yield traits. Dam breed was more influential than sire breed. Boer germplasm was not superior to Kiko or Spanish germplasm for carcass yield when semi-intensively managed on humid, subtropical pasture. Results emphasize the importance of comparative breed evaluations to provide industry with reliable information on carcass yield among goat genotypes.

The effect of weight change on changes in breast density measures over menopause in a breast cancer screening cohort.

PubMed

Wanders, Johanna Olga Pauline; Bakker, Marije Fokje; Veldhuis, Wouter Bernard; Peeters, Petra Huberdina Maria; van Gils, Carla Henrica

2015-05-30

High weight and high percentage mammographic breast density are both breast cancer risk factors but are negatively correlated. Therefore, we wanted to obtain more insight into this apparent paradox. We investigated in a longitudinal study how weight change over menopause is related to changes in mammographic breast features. Five hundred ninety-one participants of the EPIC-NL cohort were divided into three groups according to their prospectively measured weight change over menopause: (1) weight loss (more than -3.0 %), (2) stable weight (between -3.0 % and +3.0 %), and (3) weight gain (more than 3.0 %). SPSS GLM univariate analysis was used to determine both the mean breast measure changes in, and the trend over, the weight change groups. Over a median period of 5 years, the mean changes in percent density in these groups were -5.0 % (95 % confidence interval (CI) -8.0; -2.1), -6.8 % (95 % CI -9.0; -4.5), and -10.2 % (95 % CI -12.5; -7.9), respectively (P-trend = 0.001). The mean changes in dense area were -16.7 cm(2) (95 % CI -20.1; -13.4), -16.4 cm(2) (95 % CI -18.9; -13.9), and -18.1 cm(2) (95 % CI -20.6; -15.5), respectively (P-trend = 0.437). Finally, the mean changes in nondense area were -6.1 cm(2) (95 % CI -11.9; -0.4), -0.6 cm(2) (95 % CI -4.9; 3.8), and 5.3 cm(2) (95 % CI 0.9; 9.8), respectively (P-trend < 0.001). Going through menopause is associated with a decrease in both percent density and dense area. Owing to an increase in the nondense tissue, the decrease in percent density is largest in women who gain weight. The decrease in dense area is not related to weight change. So the fact that both high percent density and high weight or weight gain are associated with high postmenopausal breast cancer risk can probably not be explained by an increase (or slower decrease) of dense area in women gaining weight compared with women losing weight or maintaining a stable weight. These results suggest that weight and dense area are presumably two independent postmenopausal breast cancer risk factors.

Use of Phenylboronic Acids to Investigate Boron Function in Plants. Possible Role of Boron in Transvacuolar Cytoplasmic Strands and Cell-to-Wall Adhesion

PubMed Central

Bassil, Elias; Hu, Hening; Brown, Patrick H.

2004-01-01

The only defined physiological role of boron in plants is as a cross-linking molecule involving reversible covalent bonds with cis-diols on either side of borate. Boronic acids, which form the same reversible bonds with cis-diols but cannot cross-link two molecules, were used to selectively disrupt boron function in plants. In cultured tobacco (Nicotiana tabacum cv BY-2) cells, addition of boronic acids caused the disruption of cytoplasmic strands and cell-to-cell wall detachment. The effect of the boronic acids could be relieved by the addition of boron-complexing sugars and was proportional to the boronic acid-binding strength of the sugar. Experiments with germinating petunia (Petunia hybrida) pollen and boronate-affinity chromatography showed that boronic acids and boron compete for the same binding sites. The boronic acids appear to specifically disrupt or prevent borate-dependent cross-links important for the structural integrity of the cell, including the organization of transvacuolar cytoplasmic strands. Boron likely plays a structural role in the plant cytoskeleton. We conclude that boronic acids can be used to rapidly and reversibly induce boron deficiency-like responses and therefore are useful tools for investigating boron function in plants. PMID:15466241

Ternary ceramic thermal spraying powder and method of manufacturing thermal sprayed coating using said powder

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

Vogli, Evelina; Sherman, Andrew J.; Glasgow, Curtis P.

The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance againstmore » corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.« less

Method of fabricating boron containing coatings

DOEpatents

Makowiecki, Daniel M.; Jankowski, Alan F.

1999-01-01

Hard coatings are fabricated from boron nitride, cubic boron nitride, and multilayer boron/cubic boron nitride, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron is formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/cubic boron nitride, is produced by depositing alternate layers of boron and cubic boron nitride, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be discrete or of a blended or graded composition.

Method of fabricating boron containing coatings

DOEpatents

Makowiecki, D.M.; Jankowski, A.F.

1999-04-27

Hard coatings are fabricated from boron nitride, cubic boron nitride, and multilayer boron/cubic boron nitride, and the fabrication thereof involves magnetron sputtering in a selected atmosphere. These hard coatings may be applied to tools and engine and other parts, as well to reduce wear on tribological surfaces and electronic devices. These boron coatings contain no morphological growth features. For example, the boron is formed in an inert (e.g. argon) atmosphere, while the cubic boron nitride is formed in a reactive (e.g. nitrogen) atmosphere. The multilayer boron/cubic boron nitride, is produced by depositing alternate layers of boron and cubic boron nitride, with the alternate layers having a thickness of 1 nanometer to 1 micrometer, and at least the interfaces of the layers may be discrete or of a blended or graded composition. 3 figs.

Weight loss, weight regain, and conversions to Roux-en-Y gastric bypass: 10-year results of laparoscopic sleeve gastrectomy.

PubMed

Felsenreich, Daniel M; Langer, Felix B; Kefurt, Ronald; Panhofer, Peter; Schermann, Martin; Beckerhinn, Philipp; Sperker, Christoph; Prager, Gerhard

2016-11-01

With promising short-term results, laparoscopic sleeve gastrectomy (SG) has become the second most frequently performed bariatric procedure worldwide. Aside from a growing number of reports covering up to 10 years of follow-up, only limited data have been published so far on long-term results. The aim of the study was to present a 10-year follow-up for SG. University hospital setting, Austria. We present the first complete 10-year follow-up of 53 consecutive patients who underwent SG before 2006. In this multicenter study, weight loss success, weight regain, and revisional surgery were analyzed beside Bariatric Analysis and Reporting Outcome System (BAROS) scores. A mean maximum percent excess weight loss of 71±25% (percent total weight loss: 28±15%) was reached at a median of 12 (range 12-120) months after SG. At 10 years, a mean percent excess weight loss of 53±25% was achieved by 32 patients, corresponding to a percent total weight loss of 26.3±13.4%. Nineteen of the 53 patients (36%) were converted to Roux-en-Y gastric bypass (n = 18) or duodenal switch (n = 1) due to significant weight regain (n = 11), reflux (n = 6), or acute revision (n = 2) at a median of 36 months. Two patients died at 3 and 101 months postoperatively, unrelated to SG. A total of 31 patients (59%) suffered from weight regain of 10 kg or more, among them 24 patients (45%) with 15 kg or more, 16 patients (30%) with 20 kg or more, and 7 patients (13%) with 25 kg or more weight regain from nadir. Mean BAROS score was 2.4±2.2 at 10 years follow-up, classifying SG as "fairly efficient." Within a long-term follow-up of 10 years or more after SG, a high incidence of both significant weight regain and intractable reflux was observed, leading to conversion, most commonly to Roux-en-Y gastric bypass. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Preliminary Study of Advanced Turboprops for Low Energy Consumption

NASA Technical Reports Server (NTRS)

Kraft, G. A.; Strack, W. C.

1975-01-01

The fuel savings potential of advanced turboprops (operational about 1985) was calculated and compared with that of an advanced turbofan for use in an advanced subsonic transport. At the design point, altitude 10.67 km and Mach 0.80, turbine-inlet temperature was fixed at 1590 K while overall pressure ratio was varied from 25 to 50. The regenerative turboprop had a pressure ratio of only 10 and an 85 percent effective rotary heat exchanger. Variable camber propellers were used with an efficiency of 85 percent. The study indicated a fuel savings of 33 percent, a takeoff gross weight reduction of 15 percent, and a direct operating cost reduction of 18 percent was possible when turboprops were used instead of the reference turbofan at a range of 10 200 km. These reductions were 28, 11, and 14 percent, respectively, at a range of 5500 km. Increasing overall pressure ratio from 25 to 50 saved little fuel and slightly increased takeoff gross weight.

Improvement in cyclic oxidation of the nickel-base superalloy B-1900 by addition of one percent silicon

NASA Technical Reports Server (NTRS)

Lowell, C. E.; Miner, R. V.

1973-01-01

Cast B-1900 with and without 1 weight percent Si was subjected to cyclic oxidation at 1000 and 1100 C in air for 700 and 200 hours, respectively. The results were judged by specific weight change, metallography and X-ray diffraction. Si was found to be of significant value in reducing oxidation attack, probably by increasing scale adherence.

21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Code of Federal Regulations, 2010 CFR

2010-04-01

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

21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Code of Federal Regulations, 2011 CFR

2011-04-01

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

21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Code of Federal Regulations, 2013 CFR

2013-04-01

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

21 CFR 178.2650 - Organotin stabilizers in vinyl chloride plastics.

Code of Federal Regulations, 2012 CFR

2012-04-01

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

50 CFR 648.80 - NE Multispecies regulated mesh areas and restrictions on gear and methods of fishing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... lobster—up to 10 percent, by weight, of all other species on board or 200 lobsters, whichever is less... specified in § 648.94(c)(4), whichever is less; and American lobster—up to 10 percent, by weight, of all other species on board or 200 lobsters, whichever is less, unless otherwise restricted by landing limits...

40 CFR Table F-2 to Subpart F of... - Default Data Sources for Parameters Used for CO2 Emissions

Code of Federal Regulations, 2014 CFR

2014-07-01

... metric ton Al (metric tons C/metric tons Al) Individual facility records. Sa: sulfur content in baked anode (percent weight) 2.0. Asha: ash content in baked anode (percent weight) 0.4. CO2 Emissions From... records. Hw: annual hydrogen content in green anodes (metric tons) 0.005 × GA. BA: annual baked anode...

40 CFR Table F-2 to Subpart F of... - Default Data Sources for Parameters Used for CO2 Emissions

Code of Federal Regulations, 2013 CFR

2013-07-01

... metric ton Al (metric tons C/metric tons Al) Individual facility records. Sa: sulfur content in baked anode (percent weight) 2.0. Asha: ash content in baked anode (percent weight) 0.4. CO2 Emissions From... records. Hw: annual hydrogen content in green anodes (metric tons) 0.005 × GA. BA: annual baked anode...

40 CFR Table F-2 to Subpart F of... - Default Data Sources for Parameters Used for CO2 Emissions

Code of Federal Regulations, 2012 CFR

2012-07-01

... metric ton Al (metric tons C/metric tons Al) Individual facility records. Sa: sulfur content in baked anode (percent weight) 2.0. Asha: ash content in baked anode (percent weight) 0.4. CO2 Emissions From... records. Hw: annual hydrogen content in green anodes (metric tons) 0.005 × GA. BA: annual baked anode...

40 CFR Table F-2 to Subpart F of... - Default Data Sources for Parameters Used for CO2 Emissions

Code of Federal Regulations, 2011 CFR

2011-07-01

... metric ton Al (metric tons C/metric tons Al) Individual facility records. Sa: sulfur content in baked anode (percent weight) 2.0. Asha: ash content in baked anode (percent weight) 0.4. CO2 Emissions From... records. Hw: annual hydrogen content in green anodes (metric tons) 0.005 × GA. BA: annual baked anode...

Early Development of the Low SES Infant Weighing Less Than 1001 Grams at Birth.

ERIC Educational Resources Information Center

Finello, Karen M.; And Others

To evaluate outcomes in infants of very low birth weight born in 1982-83 to families of extremely low socioeconomic status (SES), 33 infants who weighed less than 1001 grams at birth and survived the nursery period were followed for 1 year. The sample was 79 percent Hispanic and 58 percent female. Mean birth weight was 868 grams and mean…

40 CFR Table 6 to Subpart Dddd of... - Initial Compliance Demonstrations for Work Practice Requirements

Code of Federal Regulations, 2013 CFR

2013-07-01

... furnish with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate... criteria of a “dry rotary dryer” AND you have a record of the inlet moisture content and inlet dryer... an inlet moisture content of less than or equal to 25 percent (by weight, dry basis) You meet the...

40 CFR Table 6 to Subpart Dddd of... - Initial Compliance Demonstrations for Work Practice Requirements

Code of Federal Regulations, 2014 CFR

2014-07-01

... furnish with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate... criteria of a “dry rotary dryer” AND you have a record of the inlet moisture content and inlet dryer... an inlet moisture content of less than or equal to 25 percent (by weight, dry basis) You meet the...

40 CFR Table 6 to Subpart Dddd of... - Initial Compliance Demonstrations for Work Practice Requirements

Code of Federal Regulations, 2012 CFR

2012-07-01

... furnish with an inlet moisture content less than or equal to 30 percent (by weight, dry basis) AND operate... criteria of a “dry rotary dryer” AND you have a record of the inlet moisture content and inlet dryer... an inlet moisture content of less than or equal to 25 percent (by weight, dry basis) You meet the...

Precipitation hardening austenitic superalloys

DOEpatents

Korenko, Michael K.

1985-01-01

Precipitation hardening, austenitic type superalloys are described. These alloys contain 0.5 to 1.5 weight percent silicon in combination with about 0.05 to 0.5 weight percent of a post irradiation ductility enhancing agent selected from the group of hafnium, yttrium, lanthanum and scandium, alone or in combination with each other. In addition, when hafnium or yttrium are selected, reductions in irradiation induced swelling have been noted.

Boron nitride converted carbon fiber

DOEpatents

Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

2016-04-05

This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

Preliminary study of effects of winglets on wing flutter

NASA Technical Reports Server (NTRS)

Doggett, R. V., Jr.; Farmer, M. G.

1976-01-01

Some experimental flutter results are presented over a Mach number range from about 0.70 to 0.95 for a simple, swept, tapered, flat-plate wing model having a planform representative of subsonic transport airplanes and for the same wing model equipped with two different upper surface winglets. Both winglets had the same planform and area (about 2 percent of the basic-wing area); however, one weighed about 0.3 percent of the basic-wing weight, and the other weighed about 1.8 percent of the wing weight. The addition of the lighter winglet reduced the wing-flutter dynamic pressure by about 3 percent; the heavier winglet reduced the wing-flutter dynamic pressure by about 12 percent. The experimental flutter results are compared at a Mach number of 0.80 with analytical flutter results obtained by using doublet-lattice and lifting-surface (kernel-function) unsteady aerodynamic theories.

Insurance-mandated medical weight management before bariatric surgery.

PubMed

Horwitz, Daniel; Saunders, John K; Ude-Welcome, Akuezunkpa; Parikh, Manish

2016-01-01

Many insurance companies require a medical weight management (MWM) program as a prerequisite for approval for bariatric surgery. There is debate regarding the benefit of this requirement. The objective of this study is to assess the effect of insurance-mandated MWM programs on weight loss outcomes in our bariatric surgery population. To assess the effect of insurance-mandated MWM programs on weight loss outcomes in our bariatric surgery population. University. A retrospective review of all bariatric surgery cases performed between 2009 and 2013 was conducted. Patients were stratified by payor mix based on whether the insurance company required MWM. To control for differences between groups, a bucket matching algorithm was used to match patients based on gender, age, body mass index (BMI), and surgery type (sleeve gastrectomy, gastric bypass, or gastric band). A repeated-measures regression model was created to estimate percent excess weight loss, percent excess BMI loss, and percent total weight loss. A total of 1432 bariatric surgery patients were reviewed. The bucket-matching algorithm resulted in 560 patients for final analysis. Mean age and BMI were 41 years and 43 kg/m(2), respectively, and 91% were female. The regression model found no significant differences in weight loss outcomes between the MWM group and the comparison group at 1 year and 2 years-percent total weight loss: 21.3% [95% confidence interval [CI] 20.6%-22.1%] versus 20.2% [95%CI 19.7%-20.6%) at 1 year and 23.4% [95%CI 22.6%-24.3%] versus 21.5% [95%CI 21.0%-22.0%] at 2 years. There was no difference in weight loss outcomes up to 2 years in patients who required insurance-mandated MWM programs. Longer-term studies are needed to determine the benefit of this insurance requirement. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

United States Navy Nutrition Culture and How Best to Select Food While Underway

DTIC Science & Technology

2013-12-13

3000 to 4500 calories, 10 to 15 percent of calories from protein , 55 to 70 percent from carbohydrates, and 20 to 30 percent from fat (United States...given for age, weight, or gender, with protein taking 10 to 15 percent, carbohydrates taking up 55 to 70 percent, and fat taking 20 to 30 percent of...servings for grains, protein /dairy, fruits, vegetables, fats , and calories for each of the six eating times per day (Commander Navy Installations Command

A new and effective approach to boron removal by using novel boron-specific fungi isolated from boron mining wastewater.

PubMed

Taştan, Burcu Ertit; Çakir, Dilara Nur; Dönmez, Gönül

2016-01-01

Boron-resistant fungi were isolated from the wastewater of a boron mine in Turkey. Boron removal efficiencies of Penicillium crustosum and Rhodotorula mucilaginosa were detected in different media compositions. Minimal Salt Medium (MSM) and two different waste media containing molasses (WM-1) or whey + molasses (WM-2) were tested to make this process cost effective when scaled up. Both isolates achieved high boron removal yields at the highest boron concentrations tested in MSM and WM-1. The maximum boron removal yield by P. crustosum was 45.68% at 33.95 mg l(-1) initial boron concentration in MSM, and was 38.97% at 42.76 mg l(-1) boron for R. mucilaginosa, which seemed to offer an economically feasible method of removing boron from the effluents.

Parametric trade studies on a Shuttle 2 launch system architecture

NASA Technical Reports Server (NTRS)

Stanley, Douglas O.; Talay, Theodore A.; Lepsch, Roger A.; Morris, W. Douglas; Naftel, J. Christopher; Cruz, Christopher I.

1991-01-01

A series of trade studies are presented on a complementary architecture of launch vehicles as a part of a study often referred to as Shuttle-2. The results of the trade studies performed on the vehicles of a reference Shuttle-2 mixed fleet architecture have provided an increased understanding of the relative importance of each of the major vehicle parameters. As a result of trades on the reference booster-orbiter configuration with a methane booster, the study showed that 60 percent of the total liftoff thrust should be on the booster and 40 percent on the orbiter. It was also found that the liftoff thrust to weight ratio (T/W) on the booster-orbiter should be 1.3. This leads to a low dry weight and still provides enough thrust to allow the design of a heavy lift architecture. As a result of another trade study, the dry weight of the reference booster-orbiter was chosen for a variety of operational considerations. Other trade studies on the booster-orbiter demonstrate that the cross feeding of propellant during boost phase is desirable and that engine-out capability from launch to orbit is worth the performance penalty. Technology assumptions made during the Shuttle-2 design were shown to be approx. equivalent to a 25 percent across the board weight reduction over the Space Shuttle technology. The vehicles of the Shuttle-2 architecture were also sized for a wide variety of payloads and missions to different orbits. Many of these same parametric trades were also performed on completely liquid hydrogen fueled fully reusable concepts. If a booster-orbiter is designed using liquid hydrogen engines on both the booster and orbiter, the total vehicle dry weight is only 3.0 percent higher than the reference dual-fuel booster-orbiter, and the gross weight is 3.8 percent less. For this booster-orbiter vehicle, a liftoff T/W of 1.3, a thrust of about 60 percent on the booster, and a Mach staging number of 3 all proved to be desirable. This modest dry weight increase for a liquid hydrogen fueled Shuttle-2 system should be more than offset by the elimination of the entire hydrocarbon engine development program and the savings in operation cost realized by the elimination of an entire fuel type.

Smoking cessation: barriers to success and readiness to change.

PubMed

Guirguis, Alexander B; Ray, Shaunta M; Zingone, Michelle M; Airee, Anita; Franks, Andrea S; Keenum, Amy J

2010-10-01

Smoking cessation interventions should be individualized based on patient history and readiness for change. The objective of this study was to assess stages of change and key components of smoking and cessation history among a sample of primary care patients. A telephone survey of current or recent smokers identified smoking status, stage of change, motivation, concerns, relapse history, pharmacotherapy, and social support. Of 150 participants, most were within precontemplation (22.7 percent) or contemplation (44.0 percent) stages of change; 14.0 percent were in preparation, 4.7 percent in action, and 14.7 percent in maintenance. The primary motivation for quitting was to improve general health (42.3 percent). The most common cessation-related concerns were: breaking the habit, stress, and weight gain. Pharmacotherapy was discontinued due to adverse events in 31.5 percent of users. Intratreatment social support was reported by 17.5 percent. The most common reasons for relapse were falling back into the habit (36 percent), stressful situations (27 percent), and being around other smokers (25 percent). Targeted interventions are needed for patients in either precontemplation or contemplation stages. Counseling should focus on helping patients resolve barriers to cessation and reasons for relapse, particularly stress and weight management. Pharmacotherapy should be utilized when patients are ready to quit. Increased intratreatment social support and counseling appear warranted to support behavior change and appropriate medication use.

7 CFR 52.3188 - Work sheet for dried prunes.

Code of Federal Regulations, 2011 CFR

2011-01-01

... defects, including off-color and poor texture 20 percent Poor texture, end cracks, skin or flesh damage, 3..., decay But no more than 6 percent But no more than 8 percent End cracks,2 skin or flesh damage, 3... (including all factors) 1 Percentages of defects are “by weight.” 2 Except that each 1 percent of end cracks...

Predictors of long-term weight maintenance.

PubMed

Vogels, Neeltje; Diepvens, Kristel; Westerterp-Plantenga, Margriet S

2005-12-01

The purpose of this study was to evaluate available variables of a long-term weight maintenance study to investigate possible factors predisposing to weight regain after a period of weight loss. The Maastricht Weight Maintenance Study is an ongoing longitudinal study of healthy men and women (29 men and 62 women; 18 to 65 years of age; BMI = 30.2 +/- 3.1 kg/m(2)). A variety of parameters were measured before and after a very-low-energy diet and after a follow-up of at least 2 years. Mean weight loss was 7.9 +/- 3.6 kg, and percent weight regain was 113.8 +/- 98.1%. Percent BMI regain was negatively associated with an increase in dietary restraint (r = -0.47, p < 0.05). Percent weight regain was negatively correlated with baseline resting metabolic rate (r = -0.38, p = 0.01) and baseline fat mass (r = -0.24, p = 0.05) and positively correlated with the magnitude of change in body weight (BW) expressed as maximum amplitude of BW (r = 0.21, p < 0.05). In addition, amplitude of BW was positively correlated with the frequency of dieting (r = 0.57, p < 0.01). The best predictors for weight maintenance after weight loss were an increase in dietary restraint during weight loss, a high baseline resting metabolic rate, a relatively high baseline fat mass favoring a fat-free mass-sparing effect during weight loss, a rather stable BW, and a low frequency of dieting. Therefore, BW maintenance after BW loss seems to be a multifactorial issue, including mechanisms that regulate an individuals' energy expenditure, body composition, and eating behavior in such a way that energy homeostasis is maintained.

No evidence that boron influences tree species distributions in lowland tropical forests of Panama.

PubMed

Turner, Benjamin L; Zalamea, Paul-Camilo; Condit, Richard; Winter, Klaus; Wright, S Joseph; Dalling, James W

2017-04-01

It was recently proposed that boron might be the most important nutrient structuring tree species distributions in tropical forests. Here we combine observational and experimental studies to test this hypothesis for lowland tropical forests of Panama. Plant-available boron is uniformly low in tropical forest soils of Panama and is not significantly associated with any of the > 500 species in a regional network of forest dynamics plots. Experimental manipulation of boron supply to seedlings of three tropical tree species revealed no evidence of boron deficiency or toxicity at concentrations likely to occur in tropical forest soils. Foliar boron did not correlate with soil boron along a local scale gradient of boron availability. Fifteen years of boron addition to a tropical forest increased plant-available boron by 70% but did not significantly change tree productivity or boron concentrations in live leaves, wood or leaf litter. The annual input of boron in rainfall accounts for a considerable proportion of the boron in annual litterfall and is similar to the pool of plant-available boron in the soil, and is therefore sufficient to preclude boron deficiency. We conclude that boron does not influence tree species distributions in Panama and presumably elsewhere in the lowland tropics. No claim to original US government works New Phytologist © 2016 New Phytologist Trust.

Muscular development and lean body weight in body builders and weight lifters.

PubMed

Katch, V L; Katch, F I; Moffatt, R; Gittleson, M

1980-01-01

The extent of extreme muscular development in 39 males identified as body builders (N = 18), power weight lifters (N = 13), and Olympic weight lifters (N = 8) were studied. Body composition and anthropometric data, including calculations of pre-excess muscle body weight (scale weight minus excess muscle) were obtained. The lean body weight and percent fats of the subjects were: body builders = 74.6 kg, 9.3%; power weight lifters = 73.3 kg, 9.1%; and Olympic weight lifters = 68.2 kg, 10.8%. No group differences were present in frame size, percent fat, lean body weight, skinfolds, and diameter measurements. The only group differences were for the shoulders, chest, biceps relaxed and flexed, and forearm girths. In each case the body builders were larger. Calculations of excess muscle by the Behnke method revealed that the body builders had 15.6 kg excess muscle, power weight lifters 14.8 kg, and Olympic weight lifters 13.1 kg. Somatographic comparisons revealed only slight differences between the groups, while differences with reference man were substantial.

African american women, hair care, and health barriers.

PubMed

Gathers, Raechele Cochran; Mahan, Meredith Grace

2014-09-01

The objective of this study was to elucidate the prevalence of hair loss among African American women; explore the psychosocial impact of hair grooming difficulties; and examine both perceptions related to physician encounters in this group and the relationship between hair grooming, physical activity, and weight maintenance. An anonymous retrospective and qualitative survey, the Hair Care Assessment Survey, is an 18-question novel survey instrument designed at the Henry Ford Hospital Department of Dermatology Multicultural Dermatology Center. The Hair Care Assessment Survey was distributed at church-related functions at predominantly African American metropolitan Detroit churches. Two hundred African American women from metropolitan Detroit, Michigan, aged 21 to 83. The Hair Care Assessment Survey collected data relating to hair loss and hair care, psychosocial experiences relating to hair loss, and hair care as it relates to exercise and body weight management. Data was collected on doctor-patient hair-related medical visits and experiences with commercially available ethnic hair care products. More than 50 percent reported excessive hair loss. Twenty-eight percent had visited a physician to discuss hair issues, but only 32 percent felt their physician understood African American hair. Forty-five percent reported avoiding exercise because of hair concerns, and 22 percent felt that their hair impeded maintaining healthy body weight. Hair loss affects a compelling number of African American women, and a significant number express dissatisfaction in hair-related physician encounters. Additionally, hair styling problems present a serious impediment to physical activity and weight management among this already high-risk population.

Weight outcomes audit in 1.3 million adults during their first 3 months' attendance in a commercial weight management programme.

PubMed

Stubbs, R James; Morris, Liam; Pallister, Carolyn; Horgan, Graham; Lavin, Jacquie H

2015-09-10

Over sixty percent of adults in the UK are now overweight/obese. Weight management on a national scale requires behavioural and lifestyle solutions that are accessible to large numbers of people. Evidence suggests commercial weight management programmes help people manage their weight but there is little research examining those that pay to attend such programmes rather than being referred by primary care. The objective of this analysis was to evaluate the effectiveness of a UK commercial weight management programme in self-referred, fee-paying participants. Electronic weekly weight records were collated for self-referred, fee-paying participants of Slimming World groups joining between January 2010 and April 2012. This analysis reports weight outcomes in 1,356,105 adult, non-pregnant participants during their first 3 months' attendance. Data were analysed by regression, ANOVA and for binomial outcomes, chi-squared tests using the R statistical program. Mean (SD) age was 42.3 (13.6) years, height 1.65 m (0.08) and start weight was 88.4 kg (18.8). Mean start BMI was 32.6 kg/m(2) (6.3 kg/m(2)) and 5 % of participants were men. Mean weight change of all participants was -3.9 kg (3.6), percent weight change -4.4 (3.8), and BMI change was -1.4 kg/m(2) (1.3). Mean attendance was 7.8 (4.3) sessions in their first 3 months. For participants attending at least 75 % of possible weekly sessions (n = 478,772), mean BMI change was -2.5 kg/m(2) (1.3), weight change -6.8 kg (3.7) and percent weight change -7.5 % (3.5). Weight loss was greater in men than women absolutely (-6.5 (5.3) kg vs -3.8 (3.4) kg) and as a percentage (5.7 % (4.4) vs 4.3 % (3.7)), respectively. All comparisons were significant (p < 0.001). Level of attendance and percent weight loss in the first week of attendance together accounted for 55 % of the variability in weight lost during the study period. A large-scale commercial lifestyle-based weight management programme had a significant impact on weight loss outcomes over 3 months. Higher levels of attendance led to levels of weight loss known to be associated with significant clinical benefits, which on this scale may have an impact on public health.

Alumina forming iron base superalloy

DOEpatents

Yamamoto, Yukinori; Muralidharan, Govindarajan; Brady, Michael P.

2014-08-26

An austenitic stainless steel alloy, consists essentially of, in weight percent 2.5 to 4 Al; 25 to 35 Ni; 12 to 19 Cr; at least 1, up to 4 total of at least one element selected from the group consisting of Nb and Ta; 0.5 to 3 Ti; less than 0.5 V; 0.1 to 1 of at least on element selected from the group consisting of Zr and Hf; 0.03 to 0.2 C; 0.005 to 0.1 B; and base Fe. The weight percent Fe is greater than the weight percent Ni. The alloy forms an external continuous scale including alumina, and contains coherent precipitates of .gamma.'-Ni.sub.3Al, and a stable essentially single phase FCC austenitic matrix microstructure. The austenitic matrix is essentially delta-ferrite-free and essentially BCC-phase-free.

Understanding boron through size-selected clusters: structure, chemical bonding, and fluxionality.

PubMed

Sergeeva, Alina P; Popov, Ivan A; Piazza, Zachary A; Li, Wei-Li; Romanescu, Constantin; Wang, Lai-Sheng; Boldyrev, Alexander I

2014-04-15

Boron is an interesting element with unusual polymorphism. While three-dimensional (3D) structural motifs are prevalent in bulk boron, atomic boron clusters are found to have planar or quasi-planar structures, stabilized by localized two-center-two-electron (2c-2e) σ bonds on the periphery and delocalized multicenter-two-electron (nc-2e) bonds in both σ and π frameworks. Electron delocalization is a result of boron's electron deficiency and leads to fluxional behavior, which has been observed in B13(+) and B19(-). A unique capability of the in-plane rotation of the inner atoms against the periphery of the cluster in a chosen direction by employing circularly polarized infrared radiation has been suggested. Such fluxional behaviors in boron clusters are interesting and have been proposed as molecular Wankel motors. The concepts of aromaticity and antiaromaticity have been extended beyond organic chemistry to planar boron clusters. The validity of these concepts in understanding the electronic structures of boron clusters is evident in the striking similarities of the π-systems of planar boron clusters to those of polycyclic aromatic hydrocarbons, such as benzene, naphthalene, coronene, anthracene, or phenanthrene. Chemical bonding models developed for boron clusters not only allowed the rationalization of the stability of boron clusters but also lead to the design of novel metal-centered boron wheels with a record-setting planar coordination number of 10. The unprecedented highly coordinated borometallic molecular wheels provide insights into the interactions between transition metals and boron and expand the frontier of boron chemistry. Another interesting feature discovered through cluster studies is boron transmutation. Even though it is well-known that B(-), formed by adding one electron to boron, is isoelectronic to carbon, cluster studies have considerably expanded the possibilities of new structures and new materials using the B(-)/C analogy. It is believed that the electronic transmutation concept will be effective and valuable in aiding the design of new boride materials with predictable properties. The study of boron clusters with intermediate properties between those of individual atoms and bulk solids has given rise to a unique opportunity to broaden the frontier of boron chemistry. Understanding boron clusters has spurred experimentalists and theoreticians to find new boron-based nanomaterials, such as boron fullerenes, nanotubes, two-dimensional boron, and new compounds containing boron clusters as building blocks. Here, a brief and timely overview is presented addressing the recent progress made on boron clusters and the approaches used in the authors' laboratories to determine the structure, stability, and chemical bonding of size-selected boron clusters by joint photoelectron spectroscopy and theoretical studies. Specifically, key findings on all-boron hydrocarbon analogues, metal-centered boron wheels, and electronic transmutation in boron clusters are summarized.

Development of processing procedures for advanced silicon solar cells. [antireflection coatings and short circuit currents

NASA Technical Reports Server (NTRS)

Scott-Monck, J. A.; Stella, P. M.; Avery, J. E.

1975-01-01

Ten ohm-cm silicon solar cells, 0.2 mm thick, were produced with short circuit current efficiencies up to thirteen percent and using a combination of recent technical advances. The cells were fabricated in conventional and wraparound contact configurations. Improvement in cell collection efficiency from both the short and long wavelengths region of the solar spectrum was obtained by coupling a shallow junction and an optically transparent antireflection coating with back surface field technology. Both boron diffusion and aluminum alloying techniques were evaluated for forming back surface field cells. The latter method is less complicated and is compatible with wraparound cell processing.

Borates

USGS Publications Warehouse

Crangle, R.D.

2013-01-01

Four minerals represent 90 percent of the borates used by industry worldwide — the sodium borates (tincal and kernite), calcium borate (colemanite) and the sodium-calcium borate (ulexite). Borax is a white crystalline substance, chemically known as sodium tetraborate decahydrate, and is found naturally as the mineral tincal. Boric acid is a colorless crystalline solid sold in technical, national formulary and special quality grades as granules or powder and marketed most often as anhydrous boric acid. Deposits of borates are associated with volcanic activity and arid climates, with the largest economically viable deposits located in the Mojave Desert of the United States near Boron, CA, the Alpide belt in southern Asia and the Andean belt of South America.

Upper-stage space shuttle propulsion by means of separate scramjet and rocket engines

NASA Technical Reports Server (NTRS)

Franciscus, L. C.; Allen, J. L.

1972-01-01

A preliminary mission study of a reusable vehicle from staging to orbit indicates payload advantages for a dual-propulsion system consisting of separate scramjet and rocket engines. In the analysis the scramjet operated continuously and the initiation of rocket operation was varied. For a stage weight of 500,000 lb the payload was 10.4 percent of stage weight or 70 percent greater than that of a comparable all-rocket-powered stage. When compared with a reusable two-state rocket vehicle having 50,000 lb payload, the use of the dual propulsion system for the second stage resulted in significant decreases in lift-off weight and empty weight, indicating possible lower hardware costs.

Direct current sputtering of boron from boron/boron mixtures

DOEpatents

Timberlake, J.R.; Manos, D.; Nartowitz, E.

1994-12-13

A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached; and, coating the substrate material with boron by sputtering from the boron-containing rod. 2 figures.

Recent developments with boron as a platform for novel drug design.

PubMed

Leśnikowski, Zbigniew J

2016-06-01

After decades of development, the medicinal chemistry of compounds that contain a single boron atom has matured to the present status of having equal rights with other branches of drug discovery, although it remains a relative newcomer. In contrast, the medicinal chemistry of boron clusters is less advanced, but it is expanding and may soon become a productive area of drug discovery. The author reviews the current developments of medicinal chemistry of boron and its applications in drug design. First generation boron drugs that bear a single boron atom and second generation boron drugs that utilize boron clusters as pharmacophores or modulators of bioactive molecules are discussed. The advantages and gaps in our current understanding of boron medicinal chemistry, with a special focus on boron clusters, are highlighted. Boron is not a panacea for every drug discovery problem, but there is a good chance that it will become a useful addition to the medicinal chemistry tool box. The present status of boron resembles the medicinal chemistry status of fluorine three decades ago; indeed, currently, approximately 20% of pharmaceuticals on the market contain fluorine. The fact that novel boron compounds, especially those based on abiotic polyhedral boron hydrides, are currently unfamiliar could be advantageous because organisms may be less prone to developing resistance against boron cluster-based drugs.

Understanding Boron through Size-Selected Clusters: Structure, Chemical Bonding, and Fluxionality

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

Sergeeva, Alina P.; Popov, Ivan A.; Piazza, Zachary A.

Conspectus Boron is an interesting element with unusual polymorphism. While three-dimensional (3D) structural motifs are prevalent in bulk boron, atomic boron clusters are found to have planar or quasi-planar structures, stabilized by localized two-center–two-electron (2c–2e) σ bonds on the periphery and delocalized multicenter–two-electron (nc–2e) bonds in both σ and π frameworks. Electron delocalization is a result of boron’s electron deficiency and leads to fluxional behavior, which has been observed in B13+ and B19–. A unique capability of the in-plane rotation of the inner atoms against the periphery of the cluster in a chosen direction by employing circularly polarized infrared radiationmore » has been suggested. Such fluxional behaviors in boron clusters are interesting and have been proposed as molecular Wankel motors. The concepts of aromaticity and antiaromaticity have been extended beyond organic chemistry to planar boron clusters. The validity of these concepts in understanding the electronic structures of boron clusters is evident in the striking similarities of the π-systems of planar boron clusters to those of polycyclic aromatic hydrocarbons, such as benzene, naphthalene, coronene, anthracene, or phenanthrene. Chemical bonding models developed for boron clusters not only allowed the rationalization of the stability of boron clusters but also lead to the design of novel metal-centered boron wheels with a record-setting planar coordination number of 10. The unprecedented highly coordinated borometallic molecular wheels provide insights into the interactions between transition metals and boron and expand the frontier of boron chemistry. Another interesting feature discovered through cluster studies is boron transmutation. Even though it is well-known that B–, formed by adding one electron to boron, is isoelectronic to carbon, cluster studies have considerably expanded the possibilities of new structures and new materials using the B–/C analogy. It is believed that the electronic transmutation concept will be effective and valuable in aiding the design of new boride materials with predictable properties. The study of boron clusters with intermediate properties between those of individual atoms and bulk solids has given rise to a unique opportunity to broaden the frontier of boron chemistry. Understanding boron clusters has spurred experimentalists and theoreticians to find new boron-based nanomaterials, such as boron fullerenes, nanotubes, two-dimensional boron, and new compounds containing boron clusters as building blocks. Here, a brief and timely overview is presented addressing the recent progress made on boron clusters and the approaches used in the authors’ laboratories to determine the structure, stability, and chemical bonding of size-selected boron clusters by joint photoelectron spectroscopy and theoretical studies. Specifically, key findings on all-boron hydrocarbon analogues, metal-centered boron wheels, and electronic transmutation in boron clusters are summarized.« less

An international dosimetry exchange for BNCT part II: computational dosimetry normalizations.

PubMed

Riley, K J; Binns, P J; Harling, O K; Albritton, J R; Kiger, W S; Rezaei, A; Sköld, K; Seppälä, T; Savolainen, S; Auterinen, I; Marek, M; Viererbl, L; Nievaart, V A; Moss, R L

2008-12-01

The meaningful sharing and combining of clinical results from different centers in the world performing boron neutron capture therapy (BNCT) requires improved precision in dose specification between programs. To this end absorbed dose normalizations were performed for the European clinical centers at the Joint Research Centre of the European Commission, Petten (The Netherlands), Nuclear Research Institute, Rez (Czech Republic), VTT, Espoo (Finland), and Studsvik, Nyköping (Sweden). Each European group prepared a treatment plan calculation that was bench-marked against Massachusetts Institute of Technology (MIT) dosimetry performed in a large, water-filled phantom to uniformly evaluate dose specifications with an estimated precision of +/-2%-3%. These normalizations were compared with those derived from an earlier exchange between Brookhaven National Laboratory (BNL) and MIT in the USA. Neglecting the uncertainties related to biological weighting factors, large variations between calculated and measured dose are apparent that depend upon the 10B uptake in tissue. Assuming a boron concentration of 15 microg g(-1) in normal tissue, differences in the evaluated maximum dose to brain for the same nominal specification of 10 Gy(w) at the different facilities range between 7.6 and 13.2 Gy(w) in the trials using boronophenylalanine (BPA) as the boron delivery compound and between 8.9 and 11.1 Gy(w) in the two boron sulfhydryl (BSH) studies. Most notably, the value for the same specified dose of 10 Gy(w) determined at the different participating centers using BPA is significantly higher than at BNL by 32% (MIT), 43% (VTT), 49% (JRC), and 74% (Studsvik). Conversion of dose specification is now possible between all active participants and should be incorporated into future multi-center patient analyses.

Mission Analysis and Aircraft Sizing of a Hybrid-Electric Regional Aircraft

NASA Technical Reports Server (NTRS)

Antcliff, Kevin R.; Guynn, Mark D.; Marien, Ty V.; Wells, Douglas P.; Schneider, Steven J.; Tong, Michael T.

2016-01-01

The purpose of this study was to explore advanced airframe and propulsion technologies for a small regional transport aircraft concept (approximately 50 passengers), with the goal of creating a conceptual design that delivers significant cost and performance advantages over current aircraft in that class. In turn, this could encourage airlines to open up new markets, reestablish service at smaller airports, and increase mobility and connectivity for all passengers. To meet these study goals, hybrid-electric propulsion was analyzed as the primary enabling technology. The advanced regional aircraft is analyzed with four levels of electrification, 0 percent electric with 100 percent conventional, 25 percent electric with 75 percent conventional, 50 percent electric with 50 percent conventional, and 75 percent electric with 25 percent conventional for comparison purposes. Engine models were developed to represent projected future turboprop engine performance with advanced technology and estimates of the engine weights and flowpath dimensions were developed. A low-order multi-disciplinary optimization (MDO) environment was created that could capture the unique features of parallel hybrid-electric aircraft. It is determined that at the size and range of the advanced turboprop: The battery specific energy must be 750 watt-hours per kilogram or greater for the total energy to be less than for a conventional aircraft. A hybrid vehicle would likely not be economically feasible with a battery specific energy of 500 or 750 watt-hours per kilogram based on the higher gross weight, operating empty weight, and energy costs compared to a conventional turboprop. The battery specific energy would need to reach 1000 watt-hours per kilogram by 2030 to make the electrification of its propulsion an economically feasible option. A shorter range and/or an altered propulsion-airframe integration could provide more favorable results.

Efficient Boron-Carbon-Nitrogen Nanotube Formation Via Combined Laser-Gas Flow Levitation

NASA Technical Reports Server (NTRS)

Whitney, R. Roy (Inventor); Smith, Michael W. (Inventor); Jordan, Kevin (Inventor)

2015-01-01

A process for producing boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula BxCyNz. The process utilizes a combination of laser light and nitrogen gas flow to support a boron ball target during heating of the boron ball target and production of a boron vapor plume which reacts with nitrogen or nitrogen and carbon to produce boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula BxCyNz.

Research requirements to reduce empty weight of helicopters by use of advanced materials

NASA Technical Reports Server (NTRS)

Hoffstedt, D. J.

1976-01-01

Utilization of the new, lightweight, high-strength, aerospace structural-composite (filament/matrix) materials, when specifically designed into a new aircraft, promises reductions in structural empty weight of 12 percent at recurring costs competive with metals. A program of basic and applied research and demonstration is identified with the objective of advancing the state of the art to the point where civil helicopters are confidently designed, produced, certified, and marketed by 1985. A structural empty-weight reduction of 12 percent was shown to significantly reduce energy consumption in modern high-performance helicopters.

Osteocalcin carboxylation is not associated with body weight or percent fat changes during weight loss in post-menopausal women.

PubMed

Centi, Amanda J; Booth, Sarah L; Gundberg, Caren M; Saltzman, Edward; Nicklas, Barbara; Shea, M Kyla

2015-12-01

Osteocalcin (OC) is a vitamin K-dependent bone protein used as a marker of bone formation. Mouse models have demonstrated a role for the uncarboxylated form of OC (ucOC) in energy metabolism, including energy expenditure and adiposity, but human data are equivocal. The purpose of this study was to determine the associations between changes in measures of OC and changes in body weight and percent body fat in obese, but otherwise healthy post-menopausal women undergoing a 20-week weight loss program. All participants received supplemental vitamins K and D and calcium. Body weight and body fat percentage (%BF) were assessed before and after the intervention. Serum OC [(total (tOC), ucOC, percent uncarboxylated (%ucOC)], and procollagen type 1N-terminal propeptide (P1NP; a measure of bone formation) were measured. Women lost an average of 10.9 ± 3.9 kg and 4 %BF. Serum concentrations of tOC, ucOC, %ucOC, and P1NP did not significantly change over the twenty-week intervention, nor were these measures associated with changes in weight (all p > 0.27) or %BF (all p > 0.54). Our data do not support an association between any serum measure of OC and weight or %BF loss in post-menopausal women supplemented with nutrients implicated in bone health.

Boron neutron capture therapy (BNCT) for glioblastoma multiforme: a phase II study evaluating a prolonged high-dose of boronophenylalanine (BPA).

PubMed

Henriksson, Roger; Capala, Jacek; Michanek, Annika; Lindahl, Sten-Ake; Salford, Leif G; Franzén, Lars; Blomquist, Erik; Westlin, Jan-Erik; Bergenheim, A Tommy

2008-08-01

To evaluate the efficacy and safety of boron neutron capture therapy (BNCT) for glioblastoma multiforme (GBM) using a novel protocol for the boronophenylalanine-fructose (BPA-F) infusion. This phase II study included 30 patients, 26-69 years old, with a good performance status of which 27 have undergone debulking surgery. BPA-F (900 mg BPA/kg body weight) was given i.v. over 6h. Neutron irradiation started 2h after the completion of the infusion. Follow-up reports were monitored by an independent clinical research institute. The boron-blood concentration during irradiation was 15.2-33.7 microg/g. The average weighted absorbed dose to normal brain was 3.2-6.1 Gy (W). The minimum dose to the tumour volume ranged from 15.4 to 54.3 Gy (W). Seven patients suffered from seizures, 8 from skin/mucous problem, 5 patients were stricken by thromboembolism and 4 from abdominal disturbances in close relation to BNCT. Four patients displayed 9 episodes of grade 3-4 events (WHO). At the time for follow-up, minimum ten months, 23 out of the 29 evaluable patients were dead. The median time from BNCT treatment to tumour progression was 5.8 months and the median survival time after BNCT was 14.2 months. Following progression, 13 patients were given temozolomide, two patients were re-irradiated, and two were re-operated. Patients treated with temozolomide lived considerably longer (17.7 vs. 11.6 months). The quality of life analysis demonstrated a progressive deterioration after BNCT. Although, the efficacy of BNCT in the present protocol seems to be comparable with conventional radiotherapy and the treatment time is shorter, the observed side effects and the requirement of complex infrastructure and higher resources emphasize the need of further phase I and II studies, especially directed to improve the accumulation of (10)B in tumour cells.

Boron Arsenide and Boron Phosphide for High Temperature and Luminescent Devices. [semiconductor devices - crystal growth/crystal structure

NASA Technical Reports Server (NTRS)

Chu, T. L.

1975-01-01

The crystal growth of boron arsenide and boron phosphide in the form of bulk crystals and epitaxial layers on suitable substrates is discussed. The physical, chemical, and electrical properties of the crystals and epitaxial layers are examined. Bulk crystals of boron arsenide were prepared by the chemical transport technique, and their carrier concentration and Hall mobility were measured. The growth of boron arsenide crystals from high temperature solutions was attempted without success. Bulk crystals of boron phosphide were also prepared by chemical transport and solution growth techniques. Techniques required for the fabrication of boron phosphide devices such as junction shaping, diffusion, and contact formation were investigated. Alloying techniques were developed for the formation of low-resistance ohmic contacts to boron phosphide. Four types of boron phosphide devices were fabricated: (1) metal-insulator-boron phosphide structures, (2) Schottky barriers; (3) boron phosphide-silicon carbide heterojunctions; and (4) p-n homojunctions. Easily visible red electroluminescence was observed from both epitaxial and solution grown p-n junctions.

Reliability Based Design for a Raked Wing Tip of an Airframe

NASA Technical Reports Server (NTRS)

Patnaik, Surya N.; Pai, Shantaram S.; Coroneos, Rula M.

2011-01-01

A reliability-based optimization methodology has been developed to design the raked wing tip of the Boeing 767-400 extended range airliner made of composite and metallic materials. Design is formulated for an accepted level of risk or reliability. The design variables, weight and the constraints became functions of reliability. Uncertainties in the load, strength and the material properties, as well as the design variables, were modeled as random parameters with specified distributions, like normal, Weibull or Gumbel functions. The objective function and constraint, or a failure mode, became derived functions of the risk-level. Solution to the problem produced the optimum design with weight, variables and constraints as a function of the risk-level. Optimum weight versus reliability traced out an inverted-S shaped graph. The center of the graph corresponded to a 50 percent probability of success, or one failure in two samples. Under some assumptions, this design would be quite close to the deterministic optimum solution. The weight increased when reliability exceeded 50 percent, and decreased when the reliability was compromised. A design could be selected depending on the level of risk acceptable to a situation. The optimization process achieved up to a 20-percent reduction in weight over traditional design.

Structural stability and electronic properties of an octagonal allotrope of two dimensional boron nitride.

PubMed

Takahashi, Lauren; Takahashi, Keisuke

2017-03-27

An octagonal allotrope of two dimensional boron nitride is explored through first principles calculations. Calculations show that two dimensional octagonal boron nitride can be formed with a binding energy comparable to two dimensional hexagonal boron nitride. In addition, two dimensional octagonal boron nitride is found to have a band gap smaller than two dimensional hexagonal boron nitride, suggesting the possibility of semiconductive attributes. Two dimensional octagonal boron nitride also has the ability to layer through physisorption. Defects present within two dimensional octagonal boron nitride also lead toward the introduction of a magnetic moment through the absence of boron atoms. The presence of defects is also found to render both hexagonal and octagonal boron nitrides reactive against hydrogen, where greater reactivity is seen in the presence of nitrogen. Thus, two dimensional octagonal boron nitride is confirmed with potential to tailor properties and reactivity through lattice shape and purposeful introduction of defects.

In vivo and in vitro effects of boron and boronated compounds.

PubMed

Benderdour, M; Bui-Van, T; Dicko, A; Belleville, F

1998-03-01

Boron is ubiquitously present in soils and water. Associated with pectin it is essential for vascular plants as a component of cell walls, and it stabilizes cell membranes. It is required for the growth of pollen tubes and is involved in membrane transport, stimulating H(+)-pumping ATPase activity and K+ uptake. However, a high boron concentration in the soils is toxic to plants and some boronated derivatives are used as herbicides. An absolute requirement for boron has not been definitively demonstrated in animals and humans. However, experiments with boron supplementation or deprivation show that boron is involved in calcium and bone metabolism, and its effects are more marked when other nutrients (cholecalciferol, magnesium) are deficient. Boron supplementation increases the serum concentration of 17 beta-estradiol and testosterone but boron excess has toxic effects on reproductive function. Boron may be involved in cerebral function via its effects on the transport across membranes. It affects the synthesis of the extracellular matrix and is beneficial in wound healing. Usual dietary boron consumption in humans is 1-2 mg/day for adults. As boron has been shown to have biological activity, research into the chemistry of boronated compounds has increased. Boronated compounds have been shown to be potent anti-osteoporotic, anti-inflammatory, hypolipemic, anti-coagulant and anti-neoplastic agents both in vitro and in vivo in animals.

Solution properties and spectroscopic characterization of polymeric precursors to SiNCB and BN ceramic materials

NASA Astrophysics Data System (ADS)

Cortez, E.; Remsen, E.; Chlanda, V.; Wideman, T.; Zank, G.; Carrol, P.; Sneddon, L.

1998-06-01

Boron Nitride, BN, and composite SiNCB ceramic fibers are important structural materials because of their excellent thermal and oxidative stabilities. Consequently, polymeric materials as precursors to ceramic composites are receiving increasing attention. Characterization of these materials requires the ability to evaluate simultaneous molecular weight and compositional heterogeneity within the polymer. Size exclusion chromatography equipped with viscometric and refractive index detection as well as coupled to a LC-transform device for infrared absorption analysis has been employed to examine these heterogeneities. Using these combined approaches, the solution properties and the relative amounts of individual functional groups distributed through the molecular weight distribution of SiNCB and BN polymeric precursors were characterized.

Efficient boron-carbon-nitrogen nanotube formation via combined laser-gas flow levitation

DOEpatents

Whitney, R Roy; Jordan, Kevin; Smith, Michael W

2015-03-24

A process for producing boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z. The process utilizes a combination of laser light and nitrogen gas flow to support a boron ball target during heating of the boron ball target and production of a boron vapor plume which reacts with nitrogen or nitrogen and carbon to produce boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z.

Efficient boron nitride nanotube formation via combined laser-gas flow levitation

DOEpatents

Whitney, R. Roy; Jordan, Kevin; Smith, Michael

2014-03-18

A process for producing boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z. The process utilizes a combination of laser light and nitrogen gas flow to support a boron ball target during heating of the boron ball target and production of a boron vapor plume which reacts with nitrogen or nitrogen and carbon to produce boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B.sub.xC.sub.yN.sub.z.

Efficient Boron Nitride Nanotube Formation via Combined Laser-Gas Flow Levitation

NASA Technical Reports Server (NTRS)

Whitney, R. Roy (Inventor); Jordan, Kevin (Inventor); Smith, Michael W. (Inventor)

2014-01-01

A process for producing boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B(sub x)C(sub y)N(sub z) The process utilizes a combination of laser light and nitrogen gas flow to support a boron ball target during heating of the boron ball target and production of a boron vapor plume which reacts with nitrogen or nitrogen and carbon to produce boron nitride nanotubes and/or boron-carbon-nitrogen nanotubes of the general formula B(sub x)C(sub y)N(sub z).

Direct current sputtering of boron from boron/coron mixtures

DOEpatents

Timberlake, John R.; Manos, Dennis; Nartowitz, Ed

1994-01-01

A method for coating a substrate with boron by sputtering includes lowering the electrical resistance of a boron-containing rod to allow electrical conduction in the rod; placing the boron-containing rod inside a vacuum chamber containing substrate material to be coated; applying an electrical potential between the boron target material and the vacuum chamber; countering a current avalanche that commences when the conduction heating rate exceeds the cooling rate, and until a steady equilibrium heating current is reached; and, coating the substrate material with boron by sputtering from the boron-containing rod.

Boron stress response and accumulation potential of the extremely tolerant species Puccinellia frigida.

PubMed

Rámila, Consuelo D P; Contreras, Samuel A; Di Domenico, Camila; Molina-Montenegro, Marco A; Vega, Andrea; Handford, Michael; Bonilla, Carlos A; Pizarro, Gonzalo E

2016-11-05

Phytoremediation is a promising technology to tackle boron toxicity, which restricts agricultural activities in many arid and semi-arid areas. Puccinellia frigida is a perennial grass that was reported to hyperaccumulate boron in extremely boron-contaminated sites. To further investigate its potential for phytoremediation, we determined its response to boron stress under controlled conditions (hydroponic culture). Also, as a first step towards understanding the mechanisms underlying its extreme tolerance, we evaluated the presence and expression of genes related with boron tolerance. We found that P. frigida grew normally even at highly toxic boron concentrations in the medium (500mg/L), and within its tissues (>5000mg/kg DW). We postulate that the strategies conferring this extreme tolerance involve both restricting boron accumulation and an internal tolerance mechanism; this is consistent with the identification of putative genes involved in both mechanisms, including the expression of a possible boron efflux transporter. We also found that P. frigida hyperaccumulated boron over a wide range of boron concentrations. We propose that P. frigida could be used for boron phytoremediation strategies in places with different soil characteristics and boron concentrations. Further studies should pave the way for the development of clean and low-cost solutions to boron toxicity problems. Copyright © 2016 Elsevier B.V. All rights reserved.