Tantalum-based semiconductors for solar water splitting.

PubMed

Zhang, Peng; Zhang, Jijie; Gong, Jinlong

2014-07-07

Solar energy utilization is one of the most promising solutions for the energy crises. Among all the possible means to make use of solar energy, solar water splitting is remarkable since it can accomplish the conversion of solar energy into chemical energy. The produced hydrogen is clean and sustainable which could be used in various areas. For the past decades, numerous efforts have been put into this research area with many important achievements. Improving the overall efficiency and stability of semiconductor photocatalysts are the research focuses for the solar water splitting. Tantalum-based semiconductors, including tantalum oxide, tantalate and tantalum (oxy)nitride, are among the most important photocatalysts. Tantalum oxide has the band gap energy that is suitable for the overall solar water splitting. The more negative conduction band minimum of tantalum oxide provides photogenerated electrons with higher potential for the hydrogen generation reaction. Tantalates, with tunable compositions, show high activities owning to their layered perovskite structure. (Oxy)nitrides, especially TaON and Ta3N5, have small band gaps to respond to visible-light, whereas they can still realize overall solar water splitting with the proper positions of conduction band minimum and valence band maximum. This review describes recent progress regarding the improvement of photocatalytic activities of tantalum-based semiconductors. Basic concepts and principles of solar water splitting will be discussed in the introduction section, followed by the three main categories regarding to the different types of tantalum-based semiconductors. In each category, synthetic methodologies, influencing factors on the photocatalytic activities, strategies to enhance the efficiencies of photocatalysts and morphology control of tantalum-based materials will be discussed in detail. Future directions to further explore the research area of tantalum-based semiconductors for solar water splitting

Tantalum-copper alloy and method for making

DOEpatents

Schmidt, Frederick A.; Verhoeven, John D.; Gibson, Edwin D.

1984-11-06

A tantalum-copper alloy can be made by preparing a consumable electrode consisting of an elongated copper billet containing at least two spaced apart tantalum rods extending longitudinally the length of the billet. The electrode is placed in a dc arc furnace and melted under conditions which co-melt the copper and tantalum to form the alloy.

Tantalum-copper alloy and method for making

DOEpatents

Schmidt, F.A.; Verhoeven, J.D.; Gibson, E.D.

1983-06-01

A tantalum-copper alloy can be made by preparing a consumable electrode consisting of an elongated copper billet containing at least two spaced apart tantalum rods extending longitudinally the length of the billet. The electrode is placed in a dc arc furnace and melted under conditions which co-melt the copper and tantalum to form the alloy.

Rhenium-188: Availability from the W-188/Re-188 Generator and Status of Current Applications

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

Pillai, M R A; Dash, A; Knapp Jr, Russ F

Rhenium-188 is one of the most readily available generator derived and useful radionuclides for therapy emitting - particles (2.12 MeV, 71.1% and 1.965 MeV, 25.6%) and imageable gammas (155 KeV, 15.1%). The 188W/188Re generator is an ideal source for the long term (4-6 months) continuous availability of no carrier added (nca) 188Re suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The challenges associated with the double neutron capture route of production of the parent 188W radionuclide have been a major impediment in the progress of application of 188Re. Tungsten-188 of adequate specific activity can be prepared only in 2-3more » of the high flux reactors operating in the World. Several useful technologies have been developed for the preparation of clinical grade 188W/188Re generator. Since the specific activity of 188W used in the generator is relatively low (<5 Ci/g), the eluted 188ReO4- can have low radioactive concentration often insufficient for radiopharmaceutical preparation. However, several efficient post elution concentration techniques have been developed that yield clinically useful 188ReO4-. Rhenium-188 has been used for the preparation of therapeutic radiopharmaceuticals for the management of diseases such as bone metastasis, rheumatoid arthritis and primary cancers. Several early phase clinical studies using radiopharmaceuticals based on 188Re-labeled phosphonates, antibodies, peptides, lipiodol and particulates have been reported. This article reviews the availability, and use of188Re including a discussion of why broader use of 188Re has not progressed as ecpected as a popular radionuclide for therapy.« less

Rhenium-188: availability from the (188)W/(188)Re generator and status of current applications.

PubMed

Pillai, M R A; Dash, Ashutosh; Knapp, F F

2012-07-01

Rhenium-188 is one of the most readily available generator derived and useful radionuclides for therapy emitting β(-) particles (2.12 MeV, 71.1% and 1.965 MeV, 25.6%) and imageable gammas (155 keV, 15.1%). The (188)W/(188)Re generator is an ideal source for the long term (4-6 months) continuous availability of no carrier added (nca) (188)Re suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The challenges associated with the double neutron capture route of production of the parent (188)W radionuclide have been a major impediment in the progress of application of (188)Re. Tungsten-188 of adequate specific activity can be prepared only in 2-3 of the high flux reactors operating in the World. Several useful technologies have been developed for the preparation of clinical grade (188)W/(188)Re generators. Since the specific activity of (188)W used in the generator is relatively low 185 GBq( < 5 Ci)/g], the eluted (188)ReO(4)(-) can have low radioactive concentration often insufficient for radiopharmaceutical preparation. However, several efficient post elution concentration techniques have been developed that yield clinically useful (188)ReO(4)(-) solutions. Rhenium-188 has been used for the preparation of therapeutic radiopharmaceuticals for the management of diseases such as bone metastasis, rheumatoid arthritis and primary cancers. Several early phase clinical studies using radiopharmaceuticals based on (188)Re-labeled phosphonates, antibodies, peptides, lipiodol and particulates have been reported. This article reviews the availability and use of (188)Re including a discussion of why broader use of (188)Re has not progressed as expected as a popular radionuclide for therapy.

Purification of tantalum by plasma arc melting

DOEpatents

Dunn, Paul S.; Korzekwa, Deniece R.

1999-01-01

Purification of tantalum by plasma arc melting. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc melting the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.

Ultraviolet spectrophotometric determination of tantalum with pyrogallol

USGS Publications Warehouse

Dinnin, J.I.

1953-01-01

In a search for a more rapid method for the determination of tantalum in rocks and minerals, an intensive study was made of the tantalum-pyrogallol reaction recommended by Platanov and Krivoshlikov, and a better modified spectrophotometric procedure is given. The improved method consists in measuring the absorbancy of the tantalum-pyrogallol complex at 325 m?? in 4N hydrochloric acid and a fixed concentration (0.0175M) of ammonium oxalate. Beer's law is followed for the concentration range up to 40 ?? per ml. Sensitivity in terms of molar absorbancy index is 4775. Most interferences are additive in character and readily correctable. Separations or major corrections are required in the presence of significant amounts of molybdenum, tungsten, antimony, and uranium. The method has been successfully applied to three ores previously analyzed by gravimetric techniques. The method affords greater speed, sensitivity, and reproducibility in the determination of tantalum in rocks and minerals. A more reliable technique for preparing standard solutions of tantalum has been developed.

Study of constitution diagram aluminum-tantalum

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

Glazov, V.M.; Mal'tsev, M.V.; Chistyakov, Y.D.

1988-10-20

Alloys of aluminum with tantalum were for the first time obtained by aluminothermic method in 1868 by Moriniak. Later these alloys were studied in the works of Schirmeister (1915) and Brouwer (1938), moreover Brouwer established that tantalum with aluminum forms the chemical compound TaA1, which has tetragonal crystal lattice with parameters a=5.422 angstroms and c=8.536 angstroms (1). However despite the fact that alloys of aluminum with tantalum long ago are obtained already, constitution diagram of this system is not studied until recently. In connection with the application of tantalum as the modifying additive in aluminum alloys an emergency in themore » construction of this diagram, without the knowledge by which it is not possible to give the correct explanation of the mechanism of the very process of the modification of primary grain. For this purpose was undertaken this work. Russian translations.« less

Niobium and tantalum: indispensable twins

USGS Publications Warehouse

Schulz, Klaus; Papp, John

2014-01-01

Niobium and tantalum are transition metals almost always paired together in nature. These “twins” are difficult to separate because of their shared physical and chemical properties. In 1801, English chemist Charles Hatchett uncovered an unknown element in a mineral sample of columbite; John Winthrop found the sample in a Massachusetts mine and sent it to the British Museum in London in 1734. The name columbium, which Hatchet named the new element, came from the poetic name for North America—Columbia—and was used interchangeably for niobium until 1949, when the name niobium became official. Swedish scientist Anders Ekberg discovered tantalum in 1802, but it was confused with niobium, because of their twinned properties, until 1864, when it was recognized as a separate element. Niobium is a lustrous, gray, ductile metal with a high melting point, relatively low density, and superconductor properties. Tantalum is a dark blue-gray, dense, ductile, very hard, and easily fabricated metal. It is highly conductive to heat and electricity and renowned for its resistance to acidic corrosion. These special properties determine their primary uses and make niobium and tantalum indispensable.

Rhenium-188 production in hospitals, by w-188/re-188 generator, for easy use in radionuclide therapy.

PubMed

Argyrou, Maria; Valassi, Alexia; Andreou, Maria; Lyra, Maria

2013-01-01

Rhenium-188 (Re-188) is a high energy β-emitting radioisotope obtained from the tungsten-188/rhenium-188 (W-188/Re-188) generator, which has shown utility for a variety of therapeutic applications in nuclear medicine, oncology, and interventional radiology/cardiology. Re-188 decay is accompanied by a 155 keV predominant energy γ-emission, which could be detected by γ-cameras, for imaging, biodistribution, or absorbed radiation dose studies. Its attractive physical properties and its potential low cost associated with a long-lived parent make it an interesting option for clinical use. The setup and daily use of W-188/Re-188 generator in hospital nuclear medicine departments are discussed in detail. The clinical efficacy, for several therapeutic applications, of a variety of Re-188-labeled agents is demonstrated. The high energy of the β-emission of Re-188 is particularly well suited for effective penetration in solid tumours. Its total radiation dose delivered to tissues is comparable to other radionuclides used in therapy. Furthermore, radiation safety and shielding requirements are an important subject of matter. In the case of bone metastases treatment, therapeutic ratios are presented in order to describe the efficacy of Re-188 usage.

Rhenium-188 Production in Hospitals, by W-188/Re-188 Generator, for Easy Use in Radionuclide Therapy

PubMed Central

Argyrou, Maria; Valassi, Alexia; Andreou, Maria; Lyra, Maria

2013-01-01

Rhenium-188 (Re-188) is a high energy β-emitting radioisotope obtained from the tungsten-188/rhenium-188 (W-188/Re-188) generator, which has shown utility for a variety of therapeutic applications in nuclear medicine, oncology, and interventional radiology/cardiology. Re-188 decay is accompanied by a 155 keV predominant energy γ-emission, which could be detected by γ-cameras, for imaging, biodistribution, or absorbed radiation dose studies. Its attractive physical properties and its potential low cost associated with a long-lived parent make it an interesting option for clinical use. The setup and daily use of W-188/Re-188 generator in hospital nuclear medicine departments are discussed in detail. The clinical efficacy, for several therapeutic applications, of a variety of Re-188-labeled agents is demonstrated. The high energy of the β-emission of Re-188 is particularly well suited for effective penetration in solid tumours. Its total radiation dose delivered to tissues is comparable to other radionuclides used in therapy. Furthermore, radiation safety and shielding requirements are an important subject of matter. In the case of bone metastases treatment, therapeutic ratios are presented in order to describe the efficacy of Re-188 usage. PMID:23653859

Structure refinement for tantalum nitrides nanocrystals with various morphologies

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

Liu, Lianyun; School of Science, Beijing Jiaotong University, 3 Shang Yuan Cun, Haidian District, Beijing 100044; Huang, Kai

2012-07-15

Graphical abstract: Tantalum nitrides nanocrystals with various phases and morphologies for the first time have been synthesized through homogenous sodium reduction under low temperature with the subsequent annealing process under high vacuum. Highlights: ► The spherical TaN, cuboidal TaN{sub 0.83} and TaN{sub 0.5} nanocrystals have been synthesized through homogenous sodium reduction under low temperature with the subsequent annealing process under high vacuum. ► The crystal structures of different tantalum nitrides were determined by Rietveld refinement on the X-ray diffraction data and the examinations of electron microcopies. ► The specific surface area of the tantalum nitrides powders was around 10 m{supmore » 2} g{sup −1}. ► Tantalum nitrides powders could be suitable for capacitor with high specific capacitance. -- Abstract: Tantalum nitrides (TaN{sub x}) nanocrystals with different phase and morphology have been synthesized through homogenous sodium reduction under low temperature with the subsequent annealing process under high vacuum. The crystal structures of tantalum nitrides were determined by Rietveld refinement based on the X-ray diffraction data. The morphologies of various tantalum nitrides nanocrystals in high quality were analyzed through the electron microcopies examinations. The spherical TaN nanoparticles, cuboidal TaN{sub 0.83} and TaN{sub 0.5} nanocrystals have been selectively prepared at different annealing temperatures. In addition, the specific surface areas of the tantalum nitrides nanocrystals measured by BET method were around 9.87–11.64 m{sup 2} g{sup −1}, indicating that such nano-sized tantalum nitrides could be suitable for capacitor with high specific capacitance.« less

Scintillation Breakdowns in Chip Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2008-01-01

Scintillations in solid tantalum capacitors are momentarily local breakdowns terminated by a self-healing or conversion to a high-resistive state of the manganese oxide cathode. This conversion effectively caps the defective area of the tantalum pentoxide dielectric and prevents short-circuit failures. Typically, this type of breakdown has no immediate catastrophic consequences and is often considered as nuisance rather than a failure. Scintillation breakdowns likely do not affect failures of parts under surge current conditions, and so-called "proofing" of tantalum chip capacitors, which is a controllable exposure of the part after soldering to voltages slightly higher than the operating voltage to verify that possible scintillations are self-healed, has been shown to improve the quality of the parts. However, no in-depth studies of the effect of scintillations on reliability of tantalum capacitors have been performed so far. KEMET is using scintillation breakdown testing as a tool for assessing process improvements and to compare quality of different manufacturing lots. Nevertheless, the relationship between failures and scintillation breakdowns is not clear, and this test is not considered as suitable for lot acceptance testing. In this work, scintillation breakdowns in different military-graded and commercial tantalum capacitors were characterized and related to the rated voltages and to life test failures. A model for assessment of times to failure, based on distributions of breakdown voltages, and accelerating factors of life testing are discussed.

21 CFR 886.3100 - Ophthalmic tantalum clip.

Code of Federal Regulations, 2010 CFR

2010-04-01

... blood vessels in the eye. (b) Classification. Class II (special controls). The device is exempt from the...) MEDICAL DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3100 Ophthalmic tantalum clip. (a) Identification. An ophthalmic tantalum clip is a malleable metallic device intended to be implanted permanently...

Efficacy of Tantalum Tungsten Alloys for Diffusion Barrier Applications

NASA Astrophysics Data System (ADS)

Smathers, D. B.; Aimone, P. R.

2017-12-01

Traditionally either Niobium, Tantalum or a combination of both have been used as diffusion barriers in Nb3Sn Multi-filament wire. Vanadium has also been used successfully but the ultimate RRR of the copper is limited unless an external shell of Niobium is included. Niobium is preferred over Tantalum when alternating current losses are not an issue as the Niobium will react to form Nb3Sn. Pure Tantalum tends to deform irregularly requiring extra starting thickness to ensure good barrier qualities. Our evaluations showed Tantalum lightly alloyed with 3 wt% Tungsten is compatible with the wire drawing process while deforming as well as or better than pure Niobium. Ta3wt%W has been processed as a single barrier and as a distributed barrier to fine dimensions. In addition, the higher modulus and strength of the Tantalum Tungsten alloy improves the overall tensile properties of the wire.

Hafnium radioisotope recovery from irradiated tantalum

DOEpatents

Taylor, Wayne A.; Jamriska, David J.

2001-01-01

Hafnium is recovered from irradiated tantalum by: (a) contacting the irradiated tantalum with at least one acid to obtain a solution of dissolved tantalum; (b) combining an aqueous solution of a calcium compound with the solution of dissolved tantalum to obtain a third combined solution; (c) precipitating hafnium, lanthanide, and insoluble calcium complexes from the third combined solution to obtain a first precipitate; (d) contacting the first precipitate of hafnium, lanthanide and calcium complexes with at least one fluoride ion complexing agent to form a fourth solution; (e) selectively adsorbing lanthanides and calcium from the fourth solution by cationic exchange; (f) separating fluoride ion complexing agent product from hafnium in the fourth solution by adding an aqueous solution of ferric chloride to obtain a second precipitate containing the hafnium and iron; (g) dissolving the second precipitate containing the hafnium and iron in acid to obtain an acid solution of hafnium and iron; (h) selectively adsorbing the iron from the acid solution of hafnium and iron by anionic exchange; (i) drying the ion exchanged hafnium solution to obtain hafnium isotopes. Additionally, if needed to remove residue remaining after the product is dried, dissolution in acid followed by cation exchange, then anion exchange, is performed.

Intense photoluminescence from amorphous tantalum oxide films

NASA Astrophysics Data System (ADS)

Zhu, Minmin; Zhang, Zhengjun; Miao, Wei

2006-07-01

Tantalum oxide films were deposited on silicon substrates at a temperature of ˜450°C by heating a pure tantalum foil in a rough vacuum. The films were amorphous in structure and consisted of fully oxidized Ta2O5 and (TaOx, x <2.5) suboxides. This feature resulted in strong visible light emission from the films further oxidized in the air at temperatures of 200-300°C. The mechanism for this photoluminescence behavior of the amorphous tantalum oxide films was also investigated and discussed. This study suggests that wide-band-gap materials could act as effective visible light emitters and provides a simple route to synthesize such materials.

Electronic structure and charge transport in nonstoichiometric tantalum oxide

NASA Astrophysics Data System (ADS)

Perevalov, T. V.; Gritsenko, V. A.; Gismatulin, A. A.; Voronkovskii, V. A.; Gerasimova, A. K.; Aliev, V. Sh; Prosvirin, I. A.

2018-06-01

The atomic and electronic structure of nonstoichiometric oxygen-deficient tantalum oxide TaO x<2.5 grown by ion beam sputtering deposition was studied. The TaO x film content was analyzed by x-ray photoelectron spectroscopy and by quantum-chemistry simulation. TaO x is composed of Ta2O5, metallic tantalum clusters and tantalum suboxides. A method for evaluating the stoichiometry parameter of TaO x from the comparison of experimental and theoretical photoelectron valence band spectra is proposed. The charge transport properties of TaO x were experimentally studied and the transport mechanism was quantitatively analyzed with four theoretical dielectric conductivity models. It was found that the charge transport in almost stoichiometric and nonstoichiometric tantalum oxide can be consistently described by the phonon-assisted tunneling between traps.

Hydroxyapatite Based 99Mo - 99Tc and 188W - 188Re Generator Systems

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

Knapp Jr, Russ F; Monroy-Guzman, F.; Badillo, V. E.

2006-01-01

This paper describes studies evaluating the use of hydroxyapatite as the adsorbent material for both {sup 99}Mo-{sup 99m}Tc and {sup 188}W-{sup 188}Re generator systems. Hydroxyapatite is an insoluble solid with anion exchange properties. A study of the sorption behaviour of {sup 99}Mo, {sup 99m}Tc, {sup 188}W and {sup 188}Re on hydroxyapatite in NaCl medium was evaluated by batch experiments. The results demonstrated that while {sup 99}Mo, {sup 99m}Tc and {sup 188}Re are not adsorbed by the hydroxyapatite in NaCl solutions (Kd <5), {sup 188}W is strongly adsorbed (Kd >500). On the basis of these measurements, hydroxyapatite {sup 188}W-{sup 188}Re generatormore » systems were then constructed and eluted in NaCl solutions. The hydroxyapatite based {sup 188}W-{sup 188}Re generator performances are presented.« less

High Temperature Evaluation of Tantalum Capacitors - Test 1

DOE Data Explorer

Cieslewski, Grzegorz

2014-09-28

Tantalum capacitors can provide much higher capacitance at high-temperatures than the ceramic capacitors. This study evaluates selected tantalum capacitors at high temperatures to determine their suitability for you in geothermal field. This data set contains results of the first test where three different types of capacitors were evaluated at 260C.

2017 NEPP Tasks Update for Ceramic and Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander A.

2017-01-01

This presentation gives an overview of current NEPP tasks on ceramic and tantalum capacitors and plans for the future. It includes tasks on leakage currents, gas generation and case deformation in wet tantalum capacitors; ESR degradation and acceleration factors in MnO2 and polymer cathode capacitors. Preliminary results on the effect of moisture on degradation of reverse currents in MnO2 tantalum capacitors are discussed. Latest results on mechanical characteristics of MLCCs and modeling of degradation of leakage currents in BME capacitors with defects are also presented.

METHOD OF PROTECTING TANTALUM CRUCIBLES AGAINST REACTION WITH MOLTEN URANIUM

DOEpatents

Feder, H.M.; Chellew, N.R.

1960-08-16

Tantalum crucibles against reaction with molten uranium by contacting the surfaces to be protected with metallic boron (as powder, vapor, or suspension in a liquid-volatilenonreacting medium, such as acetone and petroleum oil) at about 1800 deg C in vacuum, discontinuing contact with the boron, and heating the crucibles to a temperature of between 1800 aad 2000 deg C, whereby the tantalum boride formed in the first heating step is converted to tantalum monoboride.

Simple new method for effective concentration of 188Re solutions from alumina-based 188W-188Re generator.

PubMed

Guhlke, S; Beets, A L; Oetjen, K; Mirzadeh, S; Biersack, H J; Knapp, F F

2000-07-01

(188)Re is a useful generator-produced radioisotope currently under evaluation for a variety of therapeutic applications, including bone pain palliation and intravascular radiation therapy. Because the (188)W parent is available only in a relatively low specific activity (<0.15-0.19 GBq/mg) from reactor irradiation of enriched (186)W, relatively large volumes of 0.9% saline (>15 mL) are required for elution of the (188)Re daughter from traditional alumina-based (188)W-(188)Re generators. Because these large bolus volumes result in solutions with a relatively low specific volume activity of (188)Re (<1 GBq/mL for the 18.5-GBq generator), the availability of effective methods for eluent concentration is important. Our new approach is based on the use of 0.3 mol/L ammonium acetate as a representative salt of a weak acid instead of saline for generator elution. After generator elution, the ammonium acetate generator eluent (15-20 mL) is passed through a tandem IC-H Plus cation (Dowex-H)-anion (QMA Light) column system. Exchange of ammonium cations with hydrogen ions on the cation column forms an acetic acid solution containing perrhenate anions from which the macroscopic levels of the acetate anion of the eluent have been effectively removed. Because perrhenic acid is fully dissociated at this pH, the QMA Light column specifically traps the (188)Re-perrhenate, which is subsequently eluted with a low volume (<1 mL) of saline. Concentration ratios greater than 20:1 are readily achieved with this method. A typical clinical-scale generator loaded with 19.2 GBq (188)W was used to validate the approach. Saline elution provided (188)Re in a 75%-80% yield. Although elution with 0.15 mol/L NH4OAc gave lower yields (55%-60%), use of 0.3 mol/L NH4OAc provided yields comparable with those of saline (70%-75%). (188)W parent breakthrough was not detected after passage of the bolus through the tandem concentration system. Bolus volumes of 15-20 mL, which initially contained as much

Fabrication of a Tantalum-Based Josephson Junction for an X-Ray Detector

NASA Astrophysics Data System (ADS)

Morohashi, Shin'ichi; Gotoh, Kohtaroh; Yokoyama, Naoki

2000-06-01

We have fabricated a tantalum-based Josephson junction for an X-ray detector. The tantalum layer was selected for the junction electrode because of its long quasiparticle lifetime, large X-ray absorption efficiency and stability against thermal cycling. We have developed a buffer layer to fabricate the tantalum layer with a body-centered cubic structure. Based on careful consideration of their superconductivity, we have selected a niobium thin layer as the buffer layer for fabricating the tantalum base electrode, and a tungsten thin layer for the tantalum counter electrode. Fabricated Nb/AlOx-Al/Ta/Nb and Nb/Ta/W/AlOx-Al/Ta/Nb Josephson junctions exhibited current-voltage characteristics with a low subgap leakage current.

Extreme Response in Tension and Compression of Tantalum

NASA Astrophysics Data System (ADS)

Remington, Tane Perry

This research on a model bcc metal, tantalum, has three components: the study of tensile failure; defects generated under a nanoindenter; and dislocation velocities in an extreme regime generated by pulsed lasers. The processes of dynamic failure by spalling were established in nano, poly, and mono crystalline tantalum in recovery experiments following laser compression and release. The process of spall was characterized by different techniques: optical microscopy, scanning electron microscopy, microcomputerized tomography and electron backscatter diffraction. Additionally, the pull back signal was measured by VISAR and the pressure decay was compared with HYADES simulations. There are clear differences in the microscopic fracture mechanisms, dictated by the grain sizes. In the nano and poly crystals, spalling occurred by ductile fracture favoring grain boundaries. In the monocrystals, grain boundaries are absent, and the process was of ductile failure by void initiation, growth and coalescence. The spall strength of single crystalline tantalum was higher than the poly and nano crystals. It was experimentally confirmed that spall strength in tantalum increases with strain rate. In order to generate dislocations close to the surface, single crystalline tantalum with orientations (100), (110) and (111) was nanoindented with a Berkovich tip. Atomic force microscopy showed pile-ups of dislocations around the perimeter of the nanoindentations. Sections of nanoindentations were focused ion beam cut into transmission electron microscope foils. The mechanisms of deformation under a nanoindentation in tantalum were identified and quantified. Molecular dynamics simulations were conducted and the simulated plastic deformation proceeds by the formation of nanotwins, which rapidly evolve into shear dislocation loops. Dislocation densities under the indenter were estimated experimentally (~1.2 x 1015 m-2), by MD (~7 x1015 m-2) and through an analytical calculation (2.6--19 x10

Fabrication of a tantalum-clad tungsten target for LANSCE

NASA Astrophysics Data System (ADS)

Nelson, A. T.; O'Toole, J. A.; Valicenti, R. A.; Maloy, S. A.

2012-12-01

Development of a solid state bonding technique suitable to clad tungsten targets with tantalum was completed to improve operation of the Los Alamos Neutron Science Centers spallation target. Significant deterioration of conventional bare tungsten targets has historically resulted in transfer of tungsten into the cooling system through corrosion resulting in increased radioactivity outside the target and reduction of delivered neutron flux. The fabrication method chosen to join the tantalum cladding to the tungsten was hot isostatic pressing (HIP) given the geometry constraints of a cylindrical assembly and previous success demonstrated at KENS. Nominal HIP parameters of 1500 °C, 200 MPa, and 3 h were selected based upon previous work. Development of the process included significant surface engineering controls and characterization given tantalums propensity for oxide and carbide formation at high temperatures. In addition to rigorous acid cleaning implemented at each step of the fabrication process, a three layer tantalum foil gettering system was devised such that any free oxygen and carbon impurities contained in the argon gas within the HIP vessel was mitigated to the extent possible before coming into contact with the tantalum cladding. The result of the numerous controls and refined techniques was negligible coarsening of the native Ta2O5 surface oxide, no measureable oxygen diffusion into the tantalum bulk, and no detectable carburization despite use of argon containing up to 5 ppm oxygen and up to 40 ppm total CO, CO2, or organic contaminants. Post bond characterization of the interface revealed continuous bonding with a few microns of species interdiffusion.

ON THE GEOCHEMISTRY OF NIOBIUM AND TANTALUM IN CLAYS (in Russian)

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

Pachadzhanov, D.N.

1963-10-01

With the aid of the spectral method with a preliminary enrichment in tannin, the niobium and tantalum content was determined in some humid and arid clays of the Russian platform. The investigated samples were composed of 354 specimens. The average content of niobium in humid clays is 0.0020%, of tantalum 0.00024% (the Nb/Ta ratio is 8.4) and in arid clays is respectively the content of niobium 0.00133% and the content of tantalum 0.00009% (the Nb/Ta ratio is 14.8). The average value of the content of niobium content for all studied clays is 0.00183% and of the tantalum content 0.00020%, themore » Nb/Ta ratio being 9.1. In clays an interconnection of niobium with tantalum, as well as with aluminium, titanium, zirconium, and hafnium was observed. However, on the background of this connection some separation of the named elements is noted. A tendency for the Nb/Ta ratio shift from the region of matter removal towards the center of the marine basin was observed. The study of niobium and tantalum distribution over different clay fractions showed that one part of elements is connected with zircon and titanium minerals in aleuosand fraction (0.1-- 0.01 mm). Another, approximately similar part is contained in the proper clay fraction (<0. 01 mm), the tantalum somewhat more concentrating in the aleurosand fraction and niobium in the clay fraction. (P.C.H.)« less

Multi-scale Modeling of Plasticity in Tantalum.

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

Lim, Hojun; Battaile, Corbett Chandler.; Carroll, Jay

In this report, we present a multi-scale computational model to simulate plastic deformation of tantalum and validating experiments. In atomistic/ dislocation level, dislocation kink- pair theory is used to formulate temperature and strain rate dependent constitutive equations. The kink-pair theory is calibrated to available data from single crystal experiments to produce accurate and convenient constitutive laws. The model is then implemented into a BCC crystal plasticity finite element method (CP-FEM) model to predict temperature and strain rate dependent yield stresses of single and polycrystalline tantalum and compared with existing experimental data from the literature. Furthermore, classical continuum constitutive models describingmore » temperature and strain rate dependent flow behaviors are fit to the yield stresses obtained from the CP-FEM polycrystal predictions. The model is then used to conduct hydro- dynamic simulations of Taylor cylinder impact test and compared with experiments. In order to validate the proposed tantalum CP-FEM model with experiments, we introduce a method for quantitative comparison of CP-FEM models with various experimental techniques. To mitigate the effects of unknown subsurface microstructure, tantalum tensile specimens with a pseudo-two-dimensional grain structure and grain sizes on the order of millimeters are used. A technique combining an electron back scatter diffraction (EBSD) and high resolution digital image correlation (HR-DIC) is used to measure the texture and sub-grain strain fields upon uniaxial tensile loading at various applied strains. Deformed specimens are also analyzed with optical profilometry measurements to obtain out-of- plane strain fields. These high resolution measurements are directly compared with large-scale CP-FEM predictions. This computational method directly links fundamental dislocation physics to plastic deformations in the grain-scale and to the engineering-scale applications. Furthermore

Development and Applications of Porous Tantalum Trabecular Metal Enhanced Titanium Dental Implants

PubMed Central

Bencharit, Sompop; Byrd, Warren C.; Altarawneh, Sandra; Hosseini, Bashir; Leong, Austin; Reside, Glenn; Morelli, Thiago; Offenbacher, Steven

2013-01-01

Statement of Problem Porous tantalum trabecular metal has recently been incorporated in titanium dental implants as a new form of implant surface enhancement. However, there is little information on the applications of this material in implant dentistry. Methods We, therefore review the current literature on the basic science and clinical uses of this material. Results Porous tantalum metal is used to improve the contact between osseous structure and dental implants; and therefore presumably facilitate osseointegration. Success of porous tantalum metal in orthopedic implants led to the incorporation of porous tantalum metal in the design of root-from endosseous titanium implants. The porous tantalum three-dimensional enhancement of titanium dental implant surface allows for combining bone ongrowth together with bone ingrowth, or osseoincorporation. While little is known about the biological aspect of the porous tantalum in the oral cavity, there seems to be several possible advantages of this implant design. This article reviews the biological aspects of porous tantalum enhanced titanium dental implants, in particular the effects of anatomical consideration and oral environment to implant designs. Conclusions We propose here possible clinical situations and applications for this type of dental implant. Advantages and disadvantages of the implants as well as needed future clinical studies are discussed. PMID:23527899

World War II, tantalum, and the evolution of modern cranioplasty technique.

PubMed

Flanigan, Patrick; Kshettry, Varun R; Benzel, Edward C

2014-04-01

Cranioplasty is a unique procedure with a rich history. Since ancient times, a diverse array of materials from coconut shells to gold plates has been used for the repair of cranial defects. More recently, World War II greatly increased the demand for cranioplasty procedures and renewed interest in the search for a suitable synthetic material for cranioprostheses. Experimental evidence revealed that tantalum was biologically inert to acid and oxidative stresses. In fact, the observation that tantalum did not absorb acid resulted in the metal being named after Tantalus, the Greek mythological figure who was condemned to a pool of water in the Underworld that would recede when he tried to take a drink. In clinical use, malleability facilitated a single-stage cosmetic repair of cranial defects. Tantalum became the preferred cranioplasty material for more than 1000 procedures performed during World War II. In fact, its use was rapidly adopted in the civilian population. During World War II and the heyday of tantalum cranioplasty, there was a rapid evolution in prosthesis implantation and fixation techniques significantly shaping how cranioplasties are performed today. Several years after the war, acrylic emerged as the cranioplasty material of choice. It had several clear advantages over its metallic counterparts. Titanium, which was less radiopaque and had a more optimal thermal conductivity profile (less thermally conductive), eventually supplanted tantalum as the most common metallic cranioplasty material. While tantalum cranioplasty was popular for only a decade, it represented a significant breakthrough in synthetic cranioplasty. The experiences of wartime neurosurgeons with tantalum cranioplasty played a pivotal role in the evolution of modern cranioplasty techniques and ultimately led to a heightened understanding of the necessary attributes of an ideal synthetic cranioplasty material. Indeed, the history of tantalum cranioplasty serves as a model for innovative

Thermal shock and erosion resistant tantalum carbide ceramic material

NASA Technical Reports Server (NTRS)

Honeycutt, L., III; Manning, C. R. (Inventor)

1978-01-01

Ceramic tantalum carbide artifacts with high thermal shock and mechanical erosion resistance are provided by incorporating tungsten-rhenium and carbon particles in a tantalum carbide matrix. The mix is sintered by hot pressing to form the ceramic article which has a high fracture strength relative to its elastic modulus and thus has an improved thermal shock and mechanical erosion resistance. The tantalum carbide is preferable less than minus 100 mesh, the carbon particles are preferable less than minus 100 mesh, and the tungsten-rhenium particles are preferable elongate, having a length to thickness ratio of at least 2/1. Tungsten-rhenium wire pieces are suitable as well as graphite particles.

International strategic minerals inventory summary report; niobium (columbium) and tantalum

USGS Publications Warehouse

Crockett, R.N.; Sutphin, D.M.

1993-01-01

Major world resources of niobium and tantalum are described in this summary report of information in the International Strategic Minerals Inventory (ISMI). ISMI is a cooperative data-collection effort of earth-science and mineral-resource agencies in Australia, Canada, the Federal Republic of Germany, the Republic of South Africa, the United Kingdom, and the United States of America. Part I of this report presents an overview of the resources and potential supply of niobium and tantalum based on inventory information; Part II contains tables of both geologic and mineral-resource information and includes production data collected by ISMI participants. Niobium is used principally as an alloying element in special steels and superalloys, and tantalum is used mainly in electronics. Minerals in the columbite-tantalite series are principal ore minerals of niobium and tantalum. Pyrochlore is a principal source of niobium. These minerals are found in carbonatite, certain rocks in alkaline igneous complexes, pegmatite, and placer deposits. ISMI estimates show that there are over 7 million metric tons of niobium and almost 0.5 million metric tons of tantalum in known deposits, outside of China and the former Soviet Union, for which reliable estimates have been made. Brazilian deposits, followed by Canadian deposits, contain by far the largest source of niobium. Tantalum production is spread widely among several countries, and Brazil and Canada are the most significant of these producers. Brazil's position is further strengthened by potential byproduct columbite from tin mining. Present economically exploitable resources of niobium appear to be sufficient for the near future, but Brazil will continue to be the predominant world supplier of ferrocolumbium. Tantalum, a byproduct of tin production, has been captive to the fluctuations of that market, but resources in pegmatite in Canada and Australia make it likely that future increases in the present modest demand will be met.

Use of the ORNL Tungsten-188/Rhenium-188 Generator for Preparation of the Rhenium-188 HDD/Lipiodol Complex for Transarterial Liver Cancer Therapy

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

Knapp Jr, Russ F; Jeong, J M

2008-01-01

This work describes the installation, use, and quality control (QC) of the alumina-based tungsten-188 ({sup 188}W)/rhenium-188 ({sup 188}Re) generators provided by the Oak Ridge National Laboratory (ORNL). In addition, methods used for concentration of the {sup 188}Re-perrhenate bolus and preparation of {sup 188}Re-labeled HDD (4-hexadecyl-2,2,9,9-tetramethyl-4,7-diaza-1,10-decanethiol) for trans-arterial administration for therapy of nonresectable liver cancer also are described. The {sup 188}W/{sup 188}Re generator has a long useful shelf-life of several months and is a convenient on-site {sup 188}Re production system. {sup 188}Re has excellent therapeutic and imaging properties (T{sub 1/2} 16.9 hours; E{beta}{sub max} 2.12 MeV; 155-keV gamma ray, 15%) andmore » is cost effectively obtained on demand by saline elution of the generator. The clinical efficacy of a variety of {sup 188}Re-labeled agents has been demonstrated for several therapeutic applications. Because of the favorable physical properties of {sup 188}Re, several {sup 188}Re-labeled agents are being developed and evaluated for the treatment of nonresectable/refractory liver cancer. {sup 188}Re-labeled HDD has been the most widely studied of these agents for this application and has been introduced into clinical trials at a number of institutions. The trans-arterial administration of {sup 188}Re-labeled agents for treatment of inoperable liver cancer requires use of high-level (1-2 Ci) {sup 188}W/{sup 188}Re generators. The handling of such high levels of {sup 188}Re imposes radiological precautions normally not encountered in a radiopharmacy and adequate care and ALARA (ie, 'As Low As Reasonably Achievable') principles must be followed. The ORNL generator provides consistently high {sup 188}Re yields (>75%) and low {sup 188}W parent breakthrough (<10{sup -3}%) over an extended shelf-life of several months. However, the high elution volumes (20-40 mL for 1-2 Ci generators) can require concentration

Thermochemistry of tantalum-wall cooling system with lithium and sodium working fluids

NASA Technical Reports Server (NTRS)

Tower, L. K.

1972-01-01

Plots are presented which show the distribution of oxygen between liquid lithium and tantalum or niobium, and between liquid sodium and tantalum at elevated temperatures. Additional plots showing the composition of the gas phase above the solutions of oxygen and alkali metal are presented. The use of the plots is illustrated by an example tantalum heat pipe filled with lithium.

Nanocrystalline zirconia: a novel sorbent for the preparation of (188)W/(188)Re generator.

PubMed

Chakravarty, Rubel; Shukla, Rakesh; Tyagi, A K; Dash, Ashutosh; Venkatesh, Meera

2010-02-01

Nanocrystalline zirconia, a novel high capacity sorbent material was synthesized and tested for its utility in the preparation of (188)W/(188)Re generators. The structural investigation of the material was carried out using X-ray diffraction, surface area determination, FTIR and TEM micrograph analysis. Various experimental parameters were optimized to separate (188)Re from (188)W. The capacity of the material was found to be approximately 325mgW/g at the optimum pH. A chromatographic (188)W/(188)Re generator was developed using this material from which >80% of (188)Re generated could be eluted with 0.9% saline solution, with high radionuclidic, radiochemical and chemical purity and appreciably high radioactive concentration suitable for radiopharmaceutical applications. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Tantalum coatings for inertial confinement fusion dry wall designs

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

Taylor, L.H.; Green, L.

1996-12-31

The coating on a dry first wall inertial confinement fusion reactor must survive the target explosion and be ductile, inexpensive, and compatible with the materials in the target, i.e. have a high atomic number Z. Calculations indicate that tantalum is the best choice for the coating material. As a test of this design 1 mm tantalum coatings were plasma sprayed onto ferrite steel tubes. They were then subjected to 100 heating-cooling cycles which simulated the stressful thermal cycling which would be encountered during five years of plant startups and shutdowns. The coatings were undamaged and continued to bond well tomore » the steel. Furthermore, chemical reactions should not degrade tantalum coatings.« less

Constitutive behavior of tantalum and tantalum-tungsten alloys

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

Chen, S.R.; Gray, G.T. III

1996-10-01

The effects of strain rate, temperature, and tungsten alloying on the yield stress and the strain-hardening behavior of tantalum were investigated. The yield and flow stresses of unalloyed Ta and tantalum-tungsten alloys were found to exhibit very high rate sensitivities, while the hardening rates in Ta and Ta-W alloys were found to be insensitive to strain rate and temperature at lower temperatures or at higher strain rates. This behavior is consistent with the observation that overcoming the intrinsic Peierls stress is shown to be the rate-controlling mechanism in these materials at low temperatures. The dependence of yield stress on temperaturemore » and strain rate was found to decrease, while the strain-hardening rate increased with tungsten alloying content. The mechanical threshold stress (MTS) model was adopted to model the stress-strain behavior of unalloyed Ta and the Ta-W alloys. Parameters for the constitutive relations for Ta and the Ta-W alloys were derived for the MTS model, the Johnson-Cook (JC), and the Zerilli-Armstrong (ZA) models. The results of this study substantiate the applicability of these models for describing the high strain-rate deformation of Ta and Ta-W alloys. The JC and ZA models, however, due to their use of a power strain-hardening law, were found to yield constitutive relations for Ta and Ta-W alloys that are strongly dependent on the range of strains for which the models were optimized.« less

Development of a high performance (188)W/(188)Re generator by using a synthetic alumina.

PubMed

Lee, Jun Sig; Lee, Jong-Soup; Park, Ul-Jae; Son, Kwang-Jae; Han, Hyon-Soo

2009-01-01

A synthetic alumina functionalized with a sulfate moiety has been developed as the column material of (99)Mo/(99m)Tc and (188)W/(188)Re generators. This material is synthesized by a sol-gel processing. In order to characterize the adsorbent for the (188)W/(188)Re separation, both batch and column contact experiments were conducted. As a result of the experiments, it is found that the maximum capacity of the adsorbent for tungsten is higher than 450mg/g. Hence it is possible to produce approximately 3Ci (188)W/(188)Re generator with only 1g of the adsorbent from (188)W solutions supplied from ORNL, USA or RIAR, Russia. A demonstration study was conducted to show the performance of an (188)W/(188)Re generator column. In this study, 1Ci of (188)W purchased from RIAR, Russia, is loaded on a 0.9cm ID column packed with 0.7g of the adsorbent. Elution of (188)Re is performed every 4-7 days by using the saline solution for more than three months. Nearly 100% of tungsten is loaded by passing 5ml of the (188)W solution (pH=8) through the dry packed column at a 1ml/min flow rate. Elution efficiency of (188)Re is 70-90% by using 5ml of the saline solution. The ratio of (188)W/(188)Re in the eluted solution is 0.002-0.003%. When a Sep-Pak containing 0.26g of acid alumina is installed as a tandem column, the ratio is decreased to less than 10(-3)%. Thin layer chromatography for the eluted (188)Re solution shows 100% radiochemical purity. Also, alumina content in the eluted solution shows less than 10ppm. Through this study, the performance of this adsorbent was successfully demonstrated. By using the developed adsorbent, minimization of the generator column and consequently the volume of eluant could be possible while maintaining the quality of (188)Re just as much as that available in the market.

Mineral-deposit model for lithium-cesium-tantalum pegmatites

USGS Publications Warehouse

Bradley, Dwight C.; McCauley, Andrew D.; Stillings, Lisa L.

2017-06-20

Lithium-cesium-tantalum (LCT) pegmatites comprise a compositionally defined subset of granitic pegmatites. The major minerals are quartz, potassium feldspar, albite, and muscovite; typical accessory minerals include biotite, garnet, tourmaline, and apatite. The principal lithium ore minerals are spodumene, petalite, and lepidolite; cesium mostly comes from pollucite; and tantalum mostly comes from columbite-tantalite. Tin ore as cassiterite and beryllium ore as beryl also occur in LCT pegmatites, as do a number of gemstones and high-value museum specimens of rare minerals. Individual crystals in LCT pegmatites can be enormous: the largest spodumene was 14 meters long, the largest beryl was 18 meters long, and the largest potassium feldspar was 49 meters long.Lithium-cesium-tantalum pegmatites account for about one-fourth of the world’s lithium production, most of the tantalum production, and all of the cesium production. Giant deposits include Tanco in Canada, Greenbushes in Australia, and Bikita in Zimbabwe. The largest lithium pegmatite in the United States, at King’s Mountain, North Carolina, is no longer being mined although large reserves of lithium remain. Depending on size and attitude of the pegmatite, a variety of mining techniques are used, including artisanal surface mining, open-pit surface mining, small underground workings, and large underground operations using room-and-pillar design. In favorable circumstances, what would otherwise be gangue minerals (quartz, potassium feldspar, albite, and muscovite) can be mined along with lithium and (or) tantalum as coproducts.Most LCT pegmatites are hosted in metamorphosed supracrustal rocks in the upper greenschist to lower amphibolite facies. Lithium-cesium-tantalum pegmatite intrusions generally are emplaced late during orogeny, with emplacement being controlled by pre-existing structures. Typically, they crop out near evolved, peraluminous granites and leucogranites from which they are inferred to be

40 CFR 421.110 - Applicability: Description of the primary columbium-tantalum subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE... the production of columbium or tantalum by primary columbium-tantalum facilities. [49 FR 8817, Mar. 8...

Reliability Effects of Surge Current Testing of Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2007-01-01

Solid tantalum capacitors are widely used in space applications to filter low-frequency ripple currents in power supply circuits and stabilize DC voltages in the system. Tantalum capacitors manufactured per military specifications (MIL-PRF-55365) are established reliability components and have less than 0.001% of failures per 1000 hours (the failure rate is less than 10 FIT) for grades D or S, thus positioning these parts among electronic components with the highest reliability characteristics. Still, failures of tantalum capacitors do happen and when it occurs it might have catastrophic consequences for the system. This is due to a short-circuit failure mode, which might be damaging to a power supply, and also to the capability of tantalum capacitors with manganese cathodes to self-ignite when a failure occurs in low-impedance applications. During such a failure, a substantial amount of energy is released by exothermic reaction of the tantalum pellet with oxygen generated by the overheated manganese oxide cathode, resulting not only in destruction of the part, but also in damage of the board and surrounding components. A specific feature of tantalum capacitors, compared to ceramic parts, is a relatively large value of capacitance, which in contemporary low-size chip capacitors reaches dozens and hundreds of microfarads. This might result in so-called surge current or turn-on failures in the parts when the board is first powered up. Such a failure, which is considered as the most prevalent type of failures in tantalum capacitors [I], is due to fast changes of the voltage in the circuit, dV/dt, producing high surge current spikes, I(sub sp) = Cx(dV/dt), when current in the circuit is unrestricted. These spikes can reach hundreds of amperes and cause catastrophic failures in the system. The mechanism of surge current failures has not been understood completely yet, and different hypotheses were discussed in relevant literature. These include a sustained scintillation

Topical Report Tantalum – 2.5% Tungsten Machinability Testing

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

L. J. Lazarus

2009-09-02

Protection Association (NFPA). NFPA 484, Standard for Combustible Metals, Chapter 9 Tantalum and Annex E, supplemental Information on Tantalum require cutting oil be used when machining tantalum because it burns at such a high temperature that it breaks down the water in a water-based metalworking fluid (MWF). The NFPA guide devotes approximately 20 pages to this material. The Kansas City Plant (KCP) uses Fuchs Lubricants Ecocut Base 44 LVC as a MWF. This is a highly chlorinated oil with a high flash point (above 200° F). The chlorine is very helpful in preventing BUE (Built Up Edge) that occurs frequentlymore » with this very gummy material. The Ecocut is really a MWF additive that Fuchs uses to add chlorinated fats to other non-chlorinated MWF.« less

Advanced Wet Tantalum Capacitors: Design, Specifications and Performance

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2016-01-01

Insertion of new types of commercial, high volumetric efficiency wet tantalum capacitors in space systems requires reassessment of the existing quality assurance approaches that have been developed for capacitors manufactured to MIL-PRF-39006 requirements. The specifics of wet electrolytic capacitors is that leakage currents flowing through electrolyte can cause gas generation resulting in building up of internal gas pressure and rupture of the case. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. This presentation gives a review of specifics of the design, performance, and potential reliability risks associated with advanced wet tantalum capacitors. Problems related to setting adequate requirements for DPA, leakage currents, hermeticity, stability at low and high temperatures, ripple currents for parts operating in vacuum, and random vibration testing are discussed. Recommendations for screening and qualification to reduce risks of failures have been suggested.

Advanced Wet Tantalum Capacitors: Design, Specifications and Performance

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2017-01-01

Insertion of new types of commercial, high volumetric efficiency wet tantalum capacitors in space systems requires reassessment of the existing quality assurance approaches that have been developed for capacitors manufactured to MIL-PRF-39006 requirements. The specifics of wet electrolytic capacitors is that leakage currents flowing through electrolyte can cause gas generation resulting in building up of internal gas pressure and rupture of the case. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. This presentation gives a review of specifics of the design, performance, and potential reliability risks associated with advanced wet tantalum capacitors. Problems related to setting adequate requirements for DPA, leakage currents, hermeticity, stability at low and high temperatures, ripple currents for parts operating in vacuum, and random vibration testing are discussed. Recommendations for screening and qualification to reduce risks of failures have been suggested.

Tribological performance of polycrystalline tantalum-carbide-incorporated diamond films on silicon substrates

NASA Astrophysics Data System (ADS)

Ullah, Mahtab; Rana, Anwar Manzoor; Ahmed, E.; Malik, Abdul Sattar; Shah, Z. A.; Ahmad, Naseeb; Mehtab, Ujala; Raza, Rizwan

2018-05-01

Polycrystalline tantalum-carbide-incorporated diamond coatings have been made on unpolished side of Si (100) wafer by hot filament chemical vapor deposition process. Morphology of the coatings has been found to vary from (111) triangular-facetted to predominantly (111) square-faceted by increasing the concentration of tantalum carbide. The results have been compared to those of a diamond reference coating with no tantalum content. An increase in roughness has been observed with the increase of tantalum carbide (TaC) due to change in morphology of the diamond films. It is noticed that roughness of the coatings increases as grains become more square-faceted. It is found that diamond coatings involving tantalum carbide are not as resistant as diamond films with no TaC content and the coefficient of friction for such coatings with microcrystalline grains can be manipulated to 0·33 under high vacuum of 10-7 Torr. Such a low friction coefficient value enhances tribological behavior of unpolished Si substrates and can possibly be used in sliding applications.

Anomalous softening of yield strength in tantalum at high pressures

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

Jing, Qiumin, E-mail: j-qm@163.com; Wu, Qiang; Xu, Ji-an

2015-02-07

The pressure dependence of the yield strength of tantalum was investigated experimentally up to 101 GPa at room temperature using a diamond anvil cell. A yield strength softening is observed between 52 and 84 GPa, whereas a normal trend is observed below 52 GPa and above 84 GPa. The onset pressure of the softening is in agreement with previous results obtained by the pressure gradient method and shock wave experiments. This unusual strength softening in tantalum is not related with structural transformation, preferred orientation, or material damage. Our measurements indicate that microscopic deviatoric strain is the major reason for the observed strength softening inmore » tantalum.« less

Investigating the oxidation mechanism of tantalum nanoparticles at high heating rates

NASA Astrophysics Data System (ADS)

DeLisio, Jeffery B.; Wang, Xizheng; Wu, Tao; Egan, Garth C.; Jacob, Rohit J.; Zachariah, Michael R.

2017-12-01

Reduced diffusion length scales and increased specific surface areas of nanosized metal fuels have recently demonstrated increased reaction rates for these systems, increasing their relevance in a wide variety of applications. The most commonly employed metal fuel, aluminum, tends to oxidize rapidly near its melting point (660 °C) in addition to undergoing a phase change of the nascent oxide shell. To further expand on the understanding of nanosized metal fuel oxidation, tantalum nanoparticles were studied due to their high melting point (3017 °C) in comparison to aluminum. Both traditional slow heating rate and in-situ high heating rate techniques were used to probe the oxidation of tantalum nanoparticles in oxygen containing environments in addition to nanothermite mixtures. When oxidized by gas phase oxygen, the oxide shell of the tantalum nanoparticles rapidly crystallized creating cracks that may attribute to enhanced oxygen diffusion into the particle. In the case of tantalum based nanothermites, oxide shell crystallization was shown to induce reactive sintering with the metal oxide resulting in a narrow range of ignition temperatures independent of the metal oxide used. The oxidation mechanism was modeled using the Deal-Grove model to extract rate parameters, and theoretical burn times for tantalum based nanocomposites were calculated.

High efficiency tantalum-based ceramic composite structures

NASA Technical Reports Server (NTRS)

Stewart, David A. (Inventor); Leiser, Daniel B. (Inventor); DiFiore, Robert R. (Inventor); Katvala, Victor W. (Inventor)

2010-01-01

Tantalum-based ceramics are suitable for use in thermal protection systems. These composite structures have high efficiency surfaces (low catalytic efficiency and high emittance), thereby reducing heat flux to a spacecraft during planetary re-entry. These ceramics contain tantalum disilicide, molybdenum disilicide and borosilicate glass. The components are milled, along with a processing aid, then applied to a surface of a porous substrate, such as a fibrous silica or carbon substrate. Following application, the coating is then sintered on the substrate. The composite structure is substantially impervious to hot gas penetration and capable of surviving high heat fluxes at temperatures approaching 3000.degree. F. and above.

Use of the Oak Ridge National Laboratory tungsten-188/rhenium-188 generator for preparation of the rhenium-188 HDD/lipiodol complex for trans-arterial liver cancer therapy

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

Jeong, J M; Knapp Jr, Russ F

2008-01-01

This work describes the installation, use, and quality control (QC) of the alumina-based tungsten-188 ({sup 188}W)/rhenium-188 ({sup 188}Re) generators provided by the Oak Ridge National Laboratory (ORNL). In addition, methods used for concentration of the {sup 188}Re-perrhenate bolus and preparation of {sup 188}Re-labeled HDD (4-hexadecyl-2,2,9,9-tetramethyl-4,7-diaza-1,10-decanethiol) for trans-arterial administration for therapy of nonresectable liver cancer also are described. The {sup 188}W/{sup 188}Re generator has a long useful shelf-life of several months and is a convenient on-site {sup 188}Re production system. {sup 188}Re has excellent therapeutic and imaging properties (T{sub 1/2} 16.9 hours; E{sub {beta}max} 2.12 MeV; 155-keV gamma ray, 15%) andmore » is cost effectively obtained on demand by saline elution of the generator. The clinical efficacy of a variety of {sup 188}Re-labeled agents has been demonstrated for several therapeutic applications. Because of the favorable physical properties of {sup 188}Re, several {sup 188}Re-labeled agents are being developed and evaluated for the treatment of nonresectable/refractory liver cancer. {sup 188}Re-labeled HDD has been the most widely studied of these agents for this application and has been introduced into clinical trials at a number of institutions. The trans-arterial administration of {sup 188}Re-labeled agents for treatment of inoperable liver cancer requires use of high-level (1-2 Ci) {sup 188}W/{sup 188}Re generators. The handling of such high levels of {sup 188}Re imposes radiological precautions normally not encountered in a radiopharmacy and adequate care and ALARA (i.e., 'As Low As Reasonably Achievable') principles must be followed. The ORNL generator provides consistently high {sup 188}Re yields (>75%) and low {sup 188}W parent breakthrough (<10{sup -3}%) over an extended shelf-life of several months. However, the high elution volumes (20-40 mL for 1-2 Ci generators) can require

A niobium oxide-tantalum oxide selector-memristor self-aligned nanostack

NASA Astrophysics Data System (ADS)

Diaz Leon, Juan J.; Norris, Kate J.; Yang, J. Joshua; Sevic, John F.; Kobayashi, Nobuhiko P.

2017-03-01

The integration of nonlinear current-voltage selectors and bi-stable memristors is a paramount step for reliable operation of crossbar arrays. In this paper, the self-aligned assembly of a single nanometer-scale device that contains both a selector and a memristor is presented. The two components (i.e., selector and memristor) are vertically assembled via a self-aligned fabrication process combined with electroforming. In designing the device, niobium oxide and tantalum oxide are chosen as materials for selector and memristor, respectively. The formation of niobium oxide is visualized by exploiting the self-limiting reaction between niobium and tantalum oxide; crystalline niobium (di)oxide forms at the interface between metallic niobium and tantalum oxide via electrothermal heating, resulting in a niobium oxide selector self-aligned to a tantalum oxide memristor. A steady-state finite element analysis is used to assess the electrothermal heating expected to occur in the device. Current-voltage measurements and structural/chemical analyses conducted for the virgin device, the electroforming process, and the functional selector-memristor device are presented. The demonstration of a self-aligned, monolithically integrated selector-memristor device would pave a practical pathway to various circuits based on memristors attainable at manufacturing scales.

Analysis of Weibull Grading Test for Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2010-01-01

Weibull grading test is a powerful technique that allows selection and reliability rating of solid tantalum capacitors for military and space applications. However, inaccuracies in the existing method and non-adequate acceleration factors can result in significant, up to three orders of magnitude, errors in the calculated failure rate of capacitors. This paper analyzes deficiencies of the existing technique and recommends more accurate method of calculations. A physical model presenting failures of tantalum capacitors as time-dependent-dielectric-breakdown is used to determine voltage and temperature acceleration factors and select adequate Weibull grading test conditions. This, model is verified by highly accelerated life testing (HALT) at different temperature and voltage conditions for three types of solid chip tantalum capacitors. It is shown that parameters of the model and acceleration factors can be calculated using a general log-linear relationship for the characteristic life with two stress levels.

40 CFR 98.188 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Definitions. 98.188 Section 98.188 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Lead Production § 98.188 Definitions. All terms used in this subpart have the same...

40 CFR 98.188 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Definitions. 98.188 Section 98.188 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Lead Production § 98.188 Definitions. All terms used in this subpart have the same...

40 CFR 98.188 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Definitions. 98.188 Section 98.188 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Lead Production § 98.188 Definitions. All terms used in this subpart have the same...

40 CFR 98.188 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Definitions. 98.188 Section 98.188 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Lead Production § 98.188 Definitions. All terms used in this subpart have the same...

40 CFR 98.188 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Definitions. 98.188 Section 98.188 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Lead Production § 98.188 Definitions. All terms used in this subpart have the same...

The Tri-lab Tantalum Strength Consortium

NASA Astrophysics Data System (ADS)

Flicker, Dawn G.; Arsenlis, Thomas A.; Austin, Ryan; Barton, Nathan R.; Benage, John F.; Bronkhorst, Curt A.; Brown, Justin L.; Brown, Staci L.; Buttler, William T.; Shen, Shuh-Rong; Dattelbaum, Dana M.; Fensin, Sayu J.; Gray, George T., III; Lane, J. Matthew D.; Lim, Hojun; Luscher, D. J.; Mattsson, Thomas R.; McNabb, Dennis P.; Remington, Bruce A.; Park, Hye-Sook; Prisbrey, Shon T.; Prime, Michael B.; Scharff, Robert J.; Schraad, Mark W.; Sun, Amy C.

2017-06-01

A Tri-lab consortium of experimentalists and theorists at SNL, LLNL, and LANL is joining forces to better understand tantalum strength across an unprecedented range of loading conditions. The team is collecting and comparing tantalum strength data from Hopkinson bar, Taylor cylinder, guns, Z, Omega and the NIF. These experiments, all using Ta from a single lot, span pressures from tenths to hundreds of GPa and strain rates from 103 to 107. New experiments are underway to provide more overlap between the platforms. The experiments are being simulated with a variety of models in order to determine which processes are important under which conditions. The presentation will show results to date. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.

Observation of oxide particles below the apparent oxygen solubility limit in tantalum

NASA Technical Reports Server (NTRS)

Stecura, S.

1973-01-01

The apparent solubility of oxygen in polycrystalline tantalum as determined by the X-ray diffraction lattice parameter technique is about 1.63 atomic percent at 820 C. However, oxide particles were identified in samples containing as low as 0.5 atomic percent of oxygen. These oxide particles were present at the grain boundaries and within the grains. The number of oxide particles increased with increasing oxygen concentration in tantalum. The presence of oxide particles suggests that the true solubility of oxygen in the polycrystalline tantalum metal is probably significantly lower than that reported in the literature.

Simultaneous determination of tantalum and hafnium in silicates by neutron activation analysis

USGS Publications Warehouse

Greenland, L.P.

1968-01-01

A neutron activation procedure suitable for the routine determination of tantalum and hafnium in silicates is described. The irradiated sample is fused with sodium peroxide and leached, and the insoluble hydroxides are dissolved in dilute hydrofluoric acid-hydrochloric acid. After LaF3 and AgCl scavenges, tantalum and hafnium are separated by anion exchange. Tantalum is obtained radiochemically pure; 233Pa and 95Zr contaminants in the hafnium fraction are resolved by ??-ray spectrometry. The chemical yield of the procedure is detemined after counting by re-irradiation. Values for the 8 U.S. Geological Survey standard rocks are reported. ?? 1968.

Synthesis of Coral-Like Tantalum Oxide Films via Anodization in Mixed Organic-Inorganic Electrolytes

PubMed Central

Yu, Hongbin; Zhu, Suiyi; Yang, Xia; Wang, Xinhong; Sun, Hongwei; Huo, Mingxin

2013-01-01

We report a simple method to fabricate nano-porous tantalum oxide films via anodization with Ta foils as the anode at room temperature. A mixture of ethylene glycol, phosphoric acid, NH4F and H2O was used as the electrolyte where the nano-porous tantalum oxide could be synthesized by anodizing a tantalum foil for 1 h at 20 V in a two–electrode configuration. The as-prepared porous film exhibited a continuous, uniform and coral-like morphology. The diameters of pores ranged from 30 nm to 50 nm. The pores interlaced each other and the depth was about 150 nm. After calcination, the as-synthesized amorphous tantalum oxide could be crystallized to the orthorhombic crystal system. As observed in photocatalytic experiments, the coral-like tantalum oxide exhibited a higher photocatalytic activity for the degradation of phenol than that with a compact surface morphology, and the elimination rate of phenol increased by 66.7%. PMID:23799106

37 CFR 1.88 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false [Reserved] 1.88 Section 1.88 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES National Processing Provisions The Drawings § 1.88 [Reserved...

27 CFR 44.188 - General.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false General. 44.188 Section 44.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE... Tubes by Manufacturers and Export Warehouse Proprietors Consignment of Shipment § 44.188 General...

27 CFR 44.188 - General.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false General. 44.188 Section 44.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE... Tubes by Manufacturers and Export Warehouse Proprietors Consignment of Shipment § 44.188 General...

27 CFR 44.188 - General.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true General. 44.188 Section 44.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE... Tubes by Manufacturers and Export Warehouse Proprietors Consignment of Shipment § 44.188 General...

27 CFR 44.188 - General.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false General. 44.188 Section 44.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE... Tubes by Manufacturers and Export Warehouse Proprietors Consignment of Shipment § 44.188 General...

27 CFR 44.188 - General.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false General. 44.188 Section 44.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE... Tubes by Manufacturers and Export Warehouse Proprietors Consignment of Shipment § 44.188 General...

Biological Response of Human Bone Marrow-Derived Mesenchymal Stem Cells to Commercial Tantalum Coatings with Microscale and Nanoscale Surface Topographies

NASA Astrophysics Data System (ADS)

Skoog, Shelby A.; Kumar, Girish; Goering, Peter L.; Williams, Brian; Stiglich, Jack; Narayan, Roger J.

2016-06-01

Tantalum is a promising orthopaedic implant coating material due to its robust mechanical properties, corrosion resistance, and excellent biocompatibility. Previous studies have demonstrated improved biocompatibility and tissue integration of surface-treated tantalum coatings compared to untreated tantalum. Surface modification of tantalum coatings with biologically inspired microscale and nanoscale features may be used to evoke optimal tissue responses. The goal of this study was to evaluate commercial tantalum coatings with nanoscale, sub-microscale, and microscale surface topographies for orthopaedic and dental applications using human bone marrow-derived mesenchymal stem cells (hBMSCs). Tantalum coatings with different microscale and nanoscale surface topographies were fabricated using a diffusion process or chemical vapor deposition. Biological evaluation of the tantalum coatings using hBMSCs showed that tantalum coatings promote cellular adhesion and growth. Furthermore, hBMSC adhesion to the tantalum coatings was dependent on surface feature characteristics, with enhanced cell adhesion on sub-micrometer- and micrometer-sized surface topographies compared to hybrid nano-/microstructures. Nanostructured and microstructured tantalum coatings should be further evaluated to optimize the surface coating features to promote osteogenesis and enhance osseointegration of tantalum-based orthopaedic implants.

1 CFR 18.8 - Seal.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 1 General Provisions 1 2010-01-01 2010-01-01 false Seal. 18.8 Section 18.8 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER PREPARATION, TRANSMITTAL, AND PROCESSING OF DOCUMENTS PREPARATION AND TRANSMITTAL OF DOCUMENTS GENERALLY § 18.8 Seal. Use of a seal on an original document or...

1 CFR 18.8 - Seal.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 1 General Provisions 1 2011-01-01 2011-01-01 false Seal. 18.8 Section 18.8 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER PREPARATION, TRANSMITTAL, AND PROCESSING OF DOCUMENTS PREPARATION AND TRANSMITTAL OF DOCUMENTS GENERALLY § 18.8 Seal. Use of a seal on an original document or...

Effect of Post-HALT Annealing on Leakage Currents in Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2010-01-01

Degradation of leakage currents is often observed during life testing of tantalum capacitors and is sometimes attributed to the field-induced crystallization in amorphous anodic tantalum pentoxide dielectrics. However, degradation of leakage currents and the possibility of annealing of degraded capacitors have not been investigated yet. In this work the effect of annealing after highly accelerated life testing (HALT) on leakage currents in various types of solid tantalum capacitors was analyzed. Variations of leakage currents with time during annealing at temperatures from 125 oC to 180 oC, thermally stimulated depolarization (TSD) currents, and I-V characteristics were measured to understand the conduction mechanism and the reason for current degradation. Annealing resulted in a gradual decrease of leakage currents and restored their initial values. Repeat HALT after annealing resulted in reproducible degradation of leakage currents. The observed results are explained based on ionic charge instability (drift/diffusion of oxygen vacancies) in the tantalum pentoxide dielectrics using a modified Schottky conduction mechanism.

The Evaluation of Hydroxyapatite (HA) Coated and Uncoated Porous Tantalum for Biomedical Material Applications

NASA Astrophysics Data System (ADS)

Safuan, Nadia; Sukmana, Irza; Kadir, Mohammed Rafiq Abdul; Noviana, Deni

2014-04-01

Porous tantalum has been used as an orthopedic implant for bone defects as it has a good corrosion resistance and fatigue behaviour properties. However, there are some reports on the rejection of porous Ta after the implantation. Those clinical cases refer to the less bioactivity of metallic-based materials. This study aims to evaluate hydroxyapatite coated and uncoated porous Tantalum in order to improve the biocompatibility of porous tantalum implant and osseointegration. Porous tantalum was used as metallic-base substrate and hydroxyapatite coating has been done using plasma-spraying technique. Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FESEM) techniques were utilizes to investigate the coating characteristics while Confocal Raman Microscopy to investigate the interface and image. The effect of coating to the corrosion behaviour was assessed by employing potentiodynamic polarization tests in simulated body fluid at 37±1 °C. Based on SEM and FESEM results, the morphologies as well the weight element consists in the uncoated and hydroxyapatite coated porous tantalum were revealed. The results indicated that the decrease in corrosion current density for HA coated porous Ta compared to the uncoated porous Ta. This study concluded that by coating porous tantalum with HA supports to decrease the corrosion rate of pure porous.

NIOBIUM-TANTALUM SEPARATION

DOEpatents

Wilhelm, H.A.; Foos, R.A.

1959-01-27

The usual method for the separation of tantalum and niobium consists of a selective solvent extraction from an aqueous hydrofluoric acid solution of the metals. A difficulty encountered in this process is the fact that the corrosion problems associated with hydrofluoric acid are serious. It has been found that the corrosion caused by the hydrofluoric acid may be substantially reduced by adding to the acidic solution an amine, such as phenyl diethanolamine or aniline, and adjusting pH value to between 4 and 6.

49 CFR 572.188 - Pelvis.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Pelvis. 572.188 Section 572.188 Transportation..., 50th Percentile Adult Male § 572.188 Pelvis. (a) The pelvis (175-6000) is part of the torso assembly shown in drawing 175-0000. The pelvis is equipped with a pubic symphysis load sensor in conformance with...

49 CFR 572.188 - Pelvis.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Pelvis. 572.188 Section 572.188 Transportation..., 50th Percentile Adult Male § 572.188 Pelvis. (a) The pelvis (175-6000) is part of the torso assembly shown in drawing 175-0000. The pelvis is equipped with a pubic symphysis load sensor in conformance with...

49 CFR 572.188 - Pelvis.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Pelvis. 572.188 Section 572.188 Transportation... Percentile Adult Male § 572.188 Pelvis. (a) The pelvis (175-6000) is part of the torso assembly shown in drawing 175-0000. The pelvis is equipped with a pubic symphysis load sensor in conformance with § 572.189...

49 CFR 572.188 - Pelvis.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 7 2010-10-01 2010-10-01 false Pelvis. 572.188 Section 572.188 Transportation... Percentile Adult Male § 572.188 Pelvis. (a) The pelvis (175-6000) is part of the torso assembly shown in drawing 175-0000. The pelvis is equipped with a pubic symphysis load sensor in conformance with § 572.189...

49 CFR 572.188 - Pelvis.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Pelvis. 572.188 Section 572.188 Transportation... Percentile Adult Male § 572.188 Pelvis. (a) The pelvis (175-6000) is part of the torso assembly shown in drawing 175-0000. The pelvis is equipped with a pubic symphysis load sensor in conformance with § 572.189...

Tantalum modified ferritic iron base alloys

NASA Technical Reports Server (NTRS)

Oldrieve, R. E.; Blankenship, C. P. (Inventor)

1977-01-01

Strong ferritic alloys of the Fe-CR-Al type containing 0.4% to 2% tantalum were developed. These alloys have improved fabricability without sacrificing high temperature strength and oxidation resistance in the 800 C (1475 F) to 1040 C (1900 F) range.

Effect of Compressive Stresses on Leakage Currents in Microchip Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2012-01-01

Microchip tantalum capacitors are manufactured using new technologies that allow for production of small size capacitors (down to EIA case size 0402) with volumetric efficiency much greater than for regular chip capacitors. Due to a small size of the parts and leadless design they might be more sensitive to mechanical stresses that develop after soldering onto printed wiring boards (PWB) compared to standard chip capacitors. In this work, the effect of compressive stresses on leakage currents in capacitors has been investigated in the range of stresses up to 200 MPa. Significant, up to three orders of magnitude, variations of currents were observed after the stress exceeds a certain critical level that varied from 10 MPa to 180 MPa for capacitors used in this study. A stress-induced generation of electron traps in tantalum pentoxide dielectric is suggested to explain reversible variations of leakage currents in tantalum capacitors. Thermo-mechanical characteristics of microchip capacitors have been studied to estimate the level of stresses caused by assembly onto PWB and assess the risk of stress-related degradation and failures. Keywords: tantalum capacitors, leakage current, soldering, reliability, mechanical stress.

The preparation of tantalum powder using a MR-EMR combination process

NASA Astrophysics Data System (ADS)

Yoon, Jae Sik; Kim, Byung Il

2007-04-01

In the conventional metallothermic reduction (MR) process used to obtain tantalum powder in batch-type operation, it is difficult to control the morphology and location of the tantalum deposits. In contrast, an electronically mediated reaction (EMR) process is capable of overcoming this difficulty. It has the advantage of being a continuous process, but has the disadvantage of a poor reduction yield. A process known as the MR-EMR combination process is able to overcome the shortcomings of the MR and EMR processes. In this study, an MR-EMR combination process is applied to the production of tantalum powder via sodium reduction of K2TaF7. In the MR-EMR combination process, the total charge passed through an external circuit and the average particle size (FSSS) increase as the reduction temperature increases. In addition, the proportion of fine particles (-325 mesh) decreases as the reduction temperature increasess. The tantalum yield improved from 65 to 74% as the reduction temperature increased. Taking into account the charge, impurities, morphology, particle size and yield, a reduction temperature of 1123 K was found to be optimum for the MR-EMR combination process.

46 CFR 188.10-77 - Vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Vessel. 188.10-77 Section 188.10-77 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-77 Vessel. Where the word “vessel” is used in this subchapter, it... in Column 7 of Table 188.05-1(a). [CGFR 67-83, 33 FR 1113, Jan. 27, 1968, as amended by CGD 77-081...

46 CFR 188.10-77 - Vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Vessel. 188.10-77 Section 188.10-77 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-77 Vessel. Where the word “vessel” is used in this subchapter, it... in Column 7 of Table 188.05-1(a). [CGFR 67-83, 33 FR 1113, Jan. 27, 1968, as amended by CGD 77-081...

46 CFR 188.10-77 - Vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Vessel. 188.10-77 Section 188.10-77 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-77 Vessel. Where the word “vessel” is used in this subchapter, it... in Column 7 of Table 188.05-1(a). [CGFR 67-83, 33 FR 1113, Jan. 27, 1968, as amended by CGD 77-081...

46 CFR 188.10-77 - Vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Vessel. 188.10-77 Section 188.10-77 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-77 Vessel. Where the word “vessel” is used in this subchapter, it... in Column 7 of Table 188.05-1(a). [CGFR 67-83, 33 FR 1113, Jan. 27, 1968, as amended by CGD 77-081...

46 CFR 188.10-77 - Vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Vessel. 188.10-77 Section 188.10-77 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-77 Vessel. Where the word “vessel” is used in this subchapter, it... in Column 7 of Table 188.05-1(a). [CGFR 67-83, 33 FR 1113, Jan. 27, 1968, as amended by CGD 77-081...

Reliability of High-Voltage Tantalum Capacitors. Parts 3 and 4)

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2010-01-01

Weibull grading test is a powerful technique that allows selection and reliability rating of solid tantalum capacitors for military and space applications. However, inaccuracies in the existing method and non-adequate acceleration factors can result in significant, up to three orders of magnitude, errors in the calculated failure rate of capacitors. This paper analyzes deficiencies of the existing technique and recommends more accurate method of calculations. A physical model presenting failures of tantalum capacitors as time-dependent-dielectric-breakdown is used to determine voltage and temperature acceleration factors and select adequate Weibull grading test conditions. This model is verified by highly accelerated life testing (HALT) at different temperature and voltage conditions for three types of solid chip tantalum capacitors. It is shown that parameters of the model and acceleration factors can be calculated using a general log-linear relationship for the characteristic life with two stress levels.

Surface nanotexturing of tantalum by laser ablation in water

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

Barmina, E V; Simakin, Aleksandr V; Shafeev, Georgii A

2009-01-31

Surface nanotexturing of tantalum by ablation with short laser pulses in water has been studied experimentally using three ablation sources: a neodymium laser with a pulse duration of 350 ps, an excimer laser (248 nm) with a pulse duration of 5 ps and a Ti:sapphire laser with a pulse duration of 180 fs. The morphology of the nanotextured surfaces has been examined using a nanoprofilometer and field emission scanning electron microscope. The results demonstrate that the average size of the hillocks produced on the target surface depends on the laser energy density and is {approx}200 nm at an energy densitymore » approaching the laser-melting threshold of tantalum and a pulse duration of 350 ps. Their surface density reaches 10{sup 6} cm{sup -2}. At a pulse duration of 5 ps, the average hillock size is 60-70 nm. Nanotexturing is accompanied by changes in the absorption spectrum of the tantalum surface in the UV and visible spectral regions. The possible mechanisms of surface nanotexturing and potential applications of this effect are discussed. (nanostructures)« less

Semimicrodetermination of combined tantalum and niobium with selenous acid

USGS Publications Warehouse

Grimaldi, F.S.; Schnepfe, M.

1959-01-01

Tantalum and niobium are separated and determined gravimetrically by precipitation with selenous acid from highly acidic solutions in the absence of complexing agents. Hydrogen peroxide is used in the preparation of the solution and later catalytically destroyed during digestion of the precipitate. From 0.2 to 30 mg., separately or in mixtures, of niobium or tantalum pentoxide can be separated from mixtures containing 100 mg. each of the oxides of scandium, yttrium, cerium, vanadium, molybdenum, iron, aluminum, tin, lead, and bismuth with a single precipitation; and from 30 mg. of titanium dioxide, and 50 mg. each of the oxides of antimony and thorium, when present separately, with three precipitations. At least 50 mg. of uranium(VI) oxide can be separated with a single precipitation when present alone; otherwise, three precipitations may be needed. Zirconium does not interfere when the tantalum and niobium contents of the sample are small, but in general, zirconium as well as tungsten interfere. The method is applied to the determination of the earth acids in tantaloniobate ores.

Tantalum protective coatings for fusion reactor applications

NASA Astrophysics Data System (ADS)

Brossa, Francesco; Piatti, Giovanni; Bardy, Michel

Tantalum has a very low sputtering yield, high melting point, low vapour pressure and good mechanical properties at low and high temperatures, so it is a very interesting candidate for the first wall and blanket structural components. Tantalum coatings overcome the problems of fabrication and joining bulk Ta, thus reducing also dead weight and cost. Ta coatings were produced by chemical vapour deposition and plasma spraying on four conventional structural materials: Al, Cu, AISI 316 L and Inconel 600. The conditions which improve adherence have been studied. The composition of the films was determined by chemical means and by X-ray analysis. Metallographie examination was employed to define the morphological structure of the deposits. The adherence of the coatings was determined by subjecting the samples to bend tests and to thermal shocks.

Effects of severe stressing on tantalum capacitors

NASA Technical Reports Server (NTRS)

Shakar, J. F.; Fairfield, E. H.

1981-01-01

The ultimate capabilities of an all tantalum capacitor were determined and evaluated. The evaluation included: 175 C life; 100 cycle thermal shock; 70 g random vibration; 3000 g shock; and 90 C ase ripple current.

Micro/Nano Structural Tantalum Coating for Enhanced Osteogenic Differentiation of Human Bone Marrow Stem Cells

PubMed Central

Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin

2018-01-01

Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as transmission electron microscopy (TEM). The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs) were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta2O5 nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro. PMID:29614022

Micro/Nano Structural Tantalum Coating for Enhanced Osteogenic Differentiation of Human Bone Marrow Stem Cells.

PubMed

Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin

2018-04-03

Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as transmission electron microscopy (TEM). The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs) were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta₂O₅ nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro.

Random Vibration Testing of Advanced Wet Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2015-01-01

Advanced wet tantalum capacitors allow for improved performance of power supply systems along with substantial reduction of size and weight of the systems that is especially beneficial for space electronics. Due to launch-related stresses, acceptance testing of all space systems includes random vibration test (RVT). However, many types of advanced wet tantalum capacitors cannot pass consistently RVT at conditions specified in MIL-PRF-39006, which impedes their use in space projects. This requires a closer look at the existing requirements, modes and mechanisms of failures, specifics of test conditions, and acceptance criteria. In this work, different lots of advanced wet tantalum capacitors from four manufacturers have been tested at step stress random vibration conditions while their currents were monitored before, during, and after the testing. It has been shown that the robustness of the parts and their reliability are mostly due to effective self-healing processes and limited current spiking or minor scintillations caused by RVT do not increase the risk of failures during operation. A simple model for scintillations events has been used to simulate current spiking during RVT and optimize test conditions. The significance of scintillations and possible effects of gas generation have been discussed and test acceptance criteria for limited current spiking have been suggested.

Effects of substrate temperature on properties of pulsed dc reactively sputtered tantalum oxide films

NASA Astrophysics Data System (ADS)

Jain, Pushkar; Juneja, Jasbir S.; Bhagwat, Vinay; Rymaszewski, Eugene J.; Lu, Toh-Ming; Cale, Timothy S.

2005-05-01

The effects of substrate heating on the stoichiometry and the electrical properties of pulsed dc reactively sputtered tantalum oxide films over a range of film thickness (0.14 to 5.4 μm) are discussed. The film stoichiometry, and hence the electrical properties, of tantalum oxide films; e.g., breakdown field, leakage current density, dielectric constant, and dielectric loss are compared for two different cases: (a) when no intentional substrate/film cooling is provided, and (b) when the substrate is water cooled during deposition. All other operating conditions are the same, and the film thickness is directly related to deposition time. The tantalum oxide films deposited on the water-cooled substrates are stoichiometric, and exhibit excellent electrical properties over the entire range of film thickness. ``Noncooled'' tantalum oxide films are stoichiometric up to ~1 μm film thickness, beyond that the deposited oxide is increasingly nonstoichiometric. The presence of partially oxidized Ta in thicker (>~1 μm) noncooled tantalum oxide films causes a lower breakdown field, higher leakage current density, higher apparent dielectric constant, and dielectric loss. The growth of nonstoichiometric tantalum oxide in thicker noncooled films is attributed to decreased surface oxygen concentration due to oxygen recombination and desorption at higher film temperatures (>~100 °C). The quantitative results presented reflect experience with a specific piece of equipment; however, the procedures presented can be used to characterize deposition processes in which film stoichiometry can change.

Poloxamer 188 (P188) as an Adjunct in Prolonged Hypotensive Resuscitation

DTIC Science & Technology

2008-06-01

temperatures meets all specifications and has been approved by the FDA for use in new clinical trials assuming it continues to meet specifications. The...cancer; clinical trials , involving more than 4,000 patients, have shown it to be safe when adminis- tered intravenously.5-7 P188 has shown the ability...CH3 Current clinical supplies of P188 are formulated as a clear, colorless, sterile, non-pyrogenic solution intended for intravenous

Guidelines for the selection and application of tantalum electrolytic capacitors in highly reliable equipment

NASA Technical Reports Server (NTRS)

Holladay, A. M.

1978-01-01

Guidelines are given for the selection and application of three types of tantalum electrolytic capacitors in current use in the design of electrical and electronic circuits for space flight missions. In addition, the guidelines supplement requirements of existing military specifications used in the procurement of capacitors. A need exists for these guidelines to assist designers in preventing some of the recurring, serious problems experienced with tantalum electrolytic capacitors in the recent past. The three types of capacitors covered by these guidelines are; solid, wet foil, and tantalum cased wet slug.

Elution of Re-188 from W-188/Re-188 generators with salts of weak acids permits efficient concentration to low volumes using a new tandem cation/anion exchange system

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

Guhlke, S.; Beets, A.L.; Knapp, F.F. Jr.

1997-05-01

Re-188, available from a W-188/Re-188 generator, is an important therapeutic radioisotope for bone pain palliation, cancer therapy and intravascular brachytherapy, etc. Because of the relatively low specific activity of reactor-produced W-188 (ORNL HFIR, 296-370 MBq mCi/mg W-186 for 2 cycles), methods of concentrating the Re-188 bolus (10-12 mL) from clinical scale (18.5-37 BGq W-188) generators (5-6 gm alumina) are thus very important. We demonstrate for the first time a new strategy of generator elution with salts of weak acids and specific perrhenate anion {open_quotes}trapping{close_quotes} with QMA anion columns. Re-188 perrhenate is efficiently eluted (65-75%) from the alumina-based generator with 0.15-0.3more » M ammonium acetate. An acetic acid solution of Re-188 perrhenic acid is obtained by subsequent on-line passage of the generator eluant through a DOWEX AG 50Wx8 (200-400 mesh, H{sup +} form) column. Since acetic acid is not ionized (< 0.001%) at this pH (< pK{sub a} = 4.76) the perrhenate anion is then specifically trapped on a QMA {open_quotes}Light{close_quotes} anion extraction column. QMA elution with 0.9% NaCl, provides Re-188 perrhenate solution in <1 mL. Concentration of 10-20 mL of Re-188 solution (> 15 BGq) in <1 mL has been demonstrated using this simple new approach, which is also effective for concentration of Tc-99m from low specific activity Mo-99 (n,y) generators. The cation/anion tandem system is inexpensive and disposable and use can be easily automated. The availability of this very simple, efficient system is important for broad use of rhenium-188.« less

Electronic transitions of tantalum monofluoride

NASA Astrophysics Data System (ADS)

Ng, K. F.; Zou, Wenli; Liu, Wenjian; Cheung, A. S.-C.

2017-03-01

The electronic transition spectrum of the tantalum monofluoride (TaF) molecule in the spectral region between 448 and 560 nm has been studied using the technique of laser-ablation/reaction free jet expansion and laser induced fluorescence spectroscopy. The TaF molecule was produced by reacting laser-ablated tantalum atoms with sulfur hexafluoride gas seeded in argon. Twenty-two vibrational bands with resolved rotational structure have been recorded and analyzed, which were organized into seven electronic transitions. The X3Σ-(0+) state has been identified to be the ground state and the determined equilibrium bond length, re, and vibrational frequency, ωe, are 1.8184 Å and 700.1 cm-1, respectively. The low-lying Λ-S states and Ω sub-states of TaF were also theoretically studied at the MRCISD+Q level of theory with spin-orbit coupling. The Ω = 0+ and 2 sub-states from the -3Σ and 3Φ state have been found to be the ground and the first excited states, respectively, which agrees well with our experimental determinations. This work represents the first experimental investigation of the molecular structure of the TaF molecule.

46 CFR 188.10-15 - Coastwise.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Coastwise. 188.10-15 Section 188.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-15 Coastwise. Under this designation shall be included...

46 CFR 188.10-15 - Coastwise.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Coastwise. 188.10-15 Section 188.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-15 Coastwise. Under this designation shall be included...

46 CFR 188.10-15 - Coastwise.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Coastwise. 188.10-15 Section 188.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-15 Coastwise. Under this designation shall be included...

46 CFR 188.10-15 - Coastwise.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Coastwise. 188.10-15 Section 188.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-15 Coastwise. Under this designation shall be included...

46 CFR 188.10-15 - Coastwise.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Coastwise. 188.10-15 Section 188.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-15 Coastwise. Under this designation shall be included...

Performance and Reliability of Solid Tantalum Capacitors at Cryogenic Conditions

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2006-01-01

Performance of different types of solid tantalum capacitors was evaluated at room and low temperatures, down to 15 K. The effect of temperature on frequency dependencies of capacitance, effective series resistances (ESR), leakage currents, and breakdown voltages has been investigated and analyzed. To assess thermo-mechanical robustness of the parts, several groups of loose capacitors and those soldered on FR4 boards were subjected to multiple (up to 500) temperature cycles between room temperature and 77 K. Experiments and mathematical modeling have shown that degradation in tantalum capacitors at low temperatures is mostly due to increasing resistance of the manganese cathode layer, resulting in substantial decrease of the roll-off frequency. Absorption currents follow a power law, I approximately t(sup -m), with the exponent m varying from 0.8 to 1.1. These currents do not change significantly at cryogenic conditions and the value of the exponent remains the same down to 15 K. Variations of leakage currents with voltage can be described by Pool-Frenkel and Schottky mechanisms of conductivity, with the Schottky mechanism prevailing at cryogenic conditions. Breakdown voltages of tantalum capacitors increase and the probability of scintillations decreases at cryogenic temperatures. However, breakdown voltages measured during surge current testing decrease at liquid nitrogen (LN) compared to room-temperature conditions. Results of temperature cycling suggest that tantalum capacitors are capable of withstanding multiple exposures to cryogenic conditions, but the probability of failures varies for different part types.

Tantalum-based thin film coatings for wear resistant arthroprostheses.

PubMed

Balagna, C; Faga, M G; Spriano, S

2011-10-01

Cobalt-chromium-molybdenum alloys with high carbon content (HC-CoCrMo) are widely used as materials for arthroprosthesis, in particular in metal-on-metal (MoM) hip joints. In spite of their good wear and corrosion resistance, production of metallic wear particles and metal ion release will occur on a large time-scale. An enhancement of the metal ion level in the patient's blood and urine is often reported in clinical data. Hypersensitivity, inflammatory response and cell necrosis can occur as consequence. So implants on young patients and women on childbearing age are not so widespread. The aim of this research is the realization of a thin film coating in order to improve the biocompatibility of Co-based alloys and to reduce debris production, ion release and citotoxicity. The innovative process consists of a thermal treatment in molten salts, in order to obtain a tantalum enriched thin film coating. Tantalum is chosen because it is considered a biocompatible metal with high corrosion resistance and low ion release. Three HC-CoCrMo alloys, produced by different manufacturing processes, are tested as substrates. The coating is a thin film of TaC or it can be composed by a multilayer of two tantalum carbides and metallic tantalum, depending on the temperature of the treatment and on the carbon content of the substrate. The thin films as well the substrates are characterized from the structural, chemical and morphological point of view. Moreover mechanical behaviour of treated and untreated materials is analyzed by means of nanohardness, scratch and ball-on-disc wear tests. The coating increases the mechanical and tribological properties of HC-CoCrMo.

46 CFR 188.10-5 - Barge.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Barge. 188.10-5 Section 188.10-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-5 Barge. This term means any non-self-propelled vessel. ...

46 CFR 188.10-2 - Approved.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Approved. 188.10-2 Section 188.10-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-2 Approved. This term means approved by the Commandant unless...

46 CFR 188.10-61 - Rivers.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Rivers. 188.10-61 Section 188.10-61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-61 Rivers. Under this designation shall be included all vessels...

46 CFR 188.10-61 - Rivers.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Rivers. 188.10-61 Section 188.10-61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-61 Rivers. Under this designation shall be included all vessels...

46 CFR 188.10-5 - Barge.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Barge. 188.10-5 Section 188.10-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-5 Barge. This term means any non-self-propelled vessel. ...

46 CFR 188.10-19 - Commandant.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Commandant. 188.10-19 Section 188.10-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-19 Commandant. This term means the Commandant of the...

36 CFR 13.188 - Permit terms.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Permit terms. 13.188 Section 13.188 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL....188 Permit terms. The Superintendent shall allow for use and occupancy of a temporary facility only to...

46 CFR 188.10-33 - Headquarters.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Headquarters. 188.10-33 Section 188.10-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-33 Headquarters. This term means the Office of the...

46 CFR 188.10-5 - Barge.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Barge. 188.10-5 Section 188.10-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-5 Barge. This term means any non-self-propelled vessel. ...

46 CFR 188.10-5 - Barge.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Barge. 188.10-5 Section 188.10-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-5 Barge. This term means any non-self-propelled vessel. ...

46 CFR 188.10-61 - Rivers.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Rivers. 188.10-61 Section 188.10-61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-61 Rivers. Under this designation shall be included all vessels...

46 CFR 188.10-33 - Headquarters.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Headquarters. 188.10-33 Section 188.10-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-33 Headquarters. This term means the Commandant (CG-00...

36 CFR 13.188 - Permit terms.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Permit terms. 13.188 Section 13.188 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL....188 Permit terms. The Superintendent shall allow for use and occupancy of a temporary facility only to...

46 CFR 188.10-25 - Explosive.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

36 CFR 13.188 - Permit terms.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Permit terms. 13.188 Section 13.188 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL....188 Permit terms. The Superintendent shall allow for use and occupancy of a temporary facility only to...

46 CFR 188.10-61 - Rivers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Rivers. 188.10-61 Section 188.10-61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-61 Rivers. Under this designation shall be included all vessels...

46 CFR 188.10-2 - Approved.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Approved. 188.10-2 Section 188.10-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-2 Approved. This term means approved by the Commandant unless...

36 CFR 13.188 - Permit terms.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Permit terms. 13.188 Section 13.188 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL....188 Permit terms. The Superintendent shall allow for use and occupancy of a temporary facility only to...

46 CFR 188.10-19 - Commandant.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Commandant. 188.10-19 Section 188.10-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-19 Commandant. This term means the Commandant of the...

46 CFR 188.10-2 - Approved.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Approved. 188.10-2 Section 188.10-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-2 Approved. This term means approved by the Commandant unless...

46 CFR 188.10-33 - Headquarters.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Headquarters. 188.10-33 Section 188.10-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-33 Headquarters. This term means the Commandant (CG-00...

46 CFR 188.10-19 - Commandant.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Commandant. 188.10-19 Section 188.10-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-19 Commandant. This term means the Commandant of the...

46 CFR 188.10-5 - Barge.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Barge. 188.10-5 Section 188.10-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-5 Barge. This term means any non-self-propelled vessel. ...

46 CFR 188.10-25 - Explosive.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

46 CFR 188.10-61 - Rivers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Rivers. 188.10-61 Section 188.10-61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-61 Rivers. Under this designation shall be included all vessels...

46 CFR 188.10-19 - Commandant.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Commandant. 188.10-19 Section 188.10-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-19 Commandant. This term means the Commandant of the...

46 CFR 188.10-2 - Approved.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Approved. 188.10-2 Section 188.10-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-2 Approved. This term means approved by the Commandant unless...

46 CFR 188.10-33 - Headquarters.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Headquarters. 188.10-33 Section 188.10-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-33 Headquarters. This term means the Office of the...

46 CFR 188.10-25 - Explosive.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

36 CFR 13.188 - Permit terms.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Permit terms. 13.188 Section 13.188 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL....188 Permit terms. The Superintendent shall allow for use and occupancy of a temporary facility only to...

46 CFR 188.10-2 - Approved.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Approved. 188.10-2 Section 188.10-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-2 Approved. This term means approved by the Commandant unless...

46 CFR 188.10-25 - Explosive.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

46 CFR 188.10-25 - Explosive.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Explosive. 188.10-25 Section 188.10-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-25 Explosive. This term means a chemical compound or...

46 CFR 188.10-19 - Commandant.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Commandant. 188.10-19 Section 188.10-19 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-19 Commandant. This term means the Commandant of the...

46 CFR 188.10-33 - Headquarters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Headquarters. 188.10-33 Section 188.10-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-33 Headquarters. This term means the Office of the...

A preliminary deposit model for lithium-cesium-tantalum (LCT) pegmatites

USGS Publications Warehouse

Bradley, Dwight; McCauley, Andrew

2013-01-01

This report is part of an effort by the U.S. Geological Survey to update existing mineral deposit models and to develop new ones. We emphasize practical aspects of pegmatite geology that might directly or indirectly help in exploration for lithium-cesium-tantalum (LCT) pegmatites, or for assessing regions for pegmatite-related mineral resource potential. These deposits are an important link in the world’s supply chain of rare and strategic elements, accounting for about one-third of world lithium production, most of the tantalum, and all of the cesium.

46 CFR 188.10-37 - Label.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Label. 188.10-37 Section 188.10-37 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-37 Label. This term means the label required by 49 CFR part 172...

46 CFR 188.10-37 - Label.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Label. 188.10-37 Section 188.10-37 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-37 Label. This term means the label required by 49 CFR part 172...

46 CFR 188.10-37 - Label.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Label. 188.10-37 Section 188.10-37 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-37 Label. This term means the label required by 49 CFR part 172...

46 CFR 188.10-37 - Label.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Label. 188.10-37 Section 188.10-37 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-37 Label. This term means the label required by 49 CFR part 172...

46 CFR 188.10-37 - Label.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Label. 188.10-37 Section 188.10-37 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-37 Label. This term means the label required by 49 CFR part 172...

Deformation of Cases in High Capacitance Value Wet Tantalum Capacitors under Environmental Stresses

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2016-01-01

Internal gas pressure in hermetic wet tantalum capacitors is created by air, electrolyte vapor, and gas generated by electrochemical reactions at the electrodes. This pressure increases substantially with temperature and time of operation due to excessive leakage currents. Deformation of the case occurs when the internal pressure exceeds pressure of the environments and can raise significantly when a part operates in space. Contrary to the cylinder case wet tantalum capacitors that have external sealing by welding and internal sealing provided by the Teflon bushing and crimping of the case, no reliable internal sealing exists in the button case capacitors. Single seal design capacitors are used for high capacitance value wet tantalum capacitors manufactured per DLA L&M drawings #04003, 04005, and 10011, and require additional analysis to assure their reliable application in space systems. In this work, leakage currents and case deformation of button case capacitors were measured during different environmental test conditions. Recommendations for derating, screening and qualification testing are given. This work is a continuation of a series of NEPP reports related to quality and reliability of wet tantalum capacitors.

46 CFR 188.10-51 - Ocean.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Ocean. 188.10-51 Section 188.10-51 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-51 Ocean. Under this designation shall be included all vessels navigating the waters of any ocean, or the Gulf of Mexico more than 20 nautical miles offshore. ...

46 CFR 188.10-51 - Ocean.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Ocean. 188.10-51 Section 188.10-51 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-51 Ocean. Under this designation shall be included all vessels navigating the waters of any ocean, or the Gulf of Mexico more than 20 nautical miles offshore. ...

46 CFR 188.10-51 - Ocean.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Ocean. 188.10-51 Section 188.10-51 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-51 Ocean. Under this designation shall be included all vessels navigating the waters of any ocean, or the Gulf of Mexico more than 20 nautical miles offshore. ...

46 CFR 188.10-51 - Ocean.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Ocean. 188.10-51 Section 188.10-51 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-51 Ocean. Under this designation shall be included all vessels navigating the waters of any ocean, or the Gulf of Mexico more than 20 nautical miles offshore. ...

46 CFR 188.10-51 - Ocean.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Ocean. 188.10-51 Section 188.10-51 Shipping COAST GUARD... Terms Used in This Subchapter § 188.10-51 Ocean. Under this designation shall be included all vessels navigating the waters of any ocean, or the Gulf of Mexico more than 20 nautical miles offshore. ...

Superconducting characteristics in purified tantalum-foils

NASA Astrophysics Data System (ADS)

Hu, Qinghua; Wang, Zhihe

2018-07-01

We have conducted extensive investigations on the electrical transport and magnetization on a purified tantalum foil with extremely sharp resistive transition (transition width ΔTc < 0.02 K) at 0 T and residual resistivity ratio ρ290K/ρ5K= 16.75. Many effects, such as anisotropic field-induced resistive broadening and second peak of the magnetization-hysteresis loop, are observed in the sample. The maximum upper critical field determined by criteria of R/Rn = 0.9 is about 1.08 T rather weak compared to that in cuprate and/or iron-based superconductors. Although the value of upper critical field Hc2(0) and the field dependence of effective pinning energy U show that the flux pinning potential is weaker, the critical current density Jc(2 K, 0 T) = 1.145 × 105 A/cm2 and the effect of second peak indicate that there should be higher collective vortex pinning potential in the tantalum foil. The carriers are dominated by holes with the density n = 6.6 × 1022/cm3.

Catalytic Hydroamination of Alkynes and Norbornene with Neutral and Cationic Tantalum Imido Complexes

PubMed Central

Anderson, Laura L.; Arnold, John; Bergman, Robert G.

2005-01-01

Several tantalum imido complexes have been synthesized and shown to efficiently catalyze the hydroamination of internal and terminal alkynes. An unusual hydroamination/hydroarylation reaction of norbornene catalyzed by a highly electrophilic cationic tantalum imido complex is also reported. Factors affecting catalyst activity and selectivity are discussed along with mechanistic insights gained from stoichiometric reactions. PMID:15255680

Characterization of Tantalum Polymer Capacitors

NASA Technical Reports Server (NTRS)

Spence, Penelope

2012-01-01

Overview Reviewed data Caution must be taken when accelerating test conditions Data not useful to establish an acceleration model Introduction of new failure mechanism skewing results Evidence of Anti-Wear-Out De-doping of polymer Decreased capacitance Increased ESR Not dielectric breakdown Needs further investigation Further investigation into tantalum polymer capacitor technology Promising acceleration model for Manufacturer A Possibility for use in high-reliability space applications with suitable voltage derating.

Physically-based strength model of tantalum incorporating effects of temperature, strain rate and pressure

DOE PAGES

Lim, Hojun; Battaile, Corbett C.; Brown, Justin L.; ...

2016-06-14

In this work, we develop a tantalum strength model that incorporates e ects of temperature, strain rate and pressure. Dislocation kink-pair theory is used to incorporate temperature and strain rate e ects while the pressure dependent yield is obtained through the pressure dependent shear modulus. Material constants used in the model are parameterized from tantalum single crystal tests and polycrystalline ramp compression experiments. It is shown that the proposed strength model agrees well with the temperature and strain rate dependent yield obtained from polycrystalline tantalum experiments. Furthermore, the model accurately reproduces the pressure dependent yield stresses up to 250 GPa.more » The proposed strength model is then used to conduct simulations of a Taylor cylinder impact test and validated with experiments. This approach provides a physically-based multi-scale strength model that is able to predict the plastic deformation of polycrystalline tantalum through a wide range of temperature, strain and pressure regimes.« less

Vacuum pyrolysis characteristics and parameter optimization of recycling organic materials from waste tantalum capacitors.

PubMed

Chen, Zhenyang; Niu, Bo; Zhang, Lingen; Xu, Zhenming

2018-01-15

Recycling rare metal tantalum from waste tantalum capacitors (WTCs) is significant to alleviate the shortage of tantalum resource. However, environmental problems will be caused if the organic materials from WTCs are improperly disposed. This study presented a promising vacuum pyrolysis technology to recycle the organic materials from WTCs. The organics removal rate could reach 94.32wt% according to TG results. The optimal parameters were determined as 425°C, 50Pa and 30min on the basis of response surface methodology (RSM). The oil yield and residual rate was 18.09wt% and 74.94wt%, respectively. All pyrolysis products can be recycled through a reasonable route. Besides, to deeply understand the pyrolysis process, the pyrolysis mechanism was also proposed based on the product and free radical theory. This paper provides an efficient process for recycling the organic material from WTCs, which can facilitate the following tantalum recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

Corrosion resistance of porous binary tantalum and titanium carbides of various composition

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

Artyunina, N.P.; Komratov, G.N.; Bolonova, E.A.

1993-12-20

Resistance of porous binary tantalum and titanium carbides in solutions of mineral acids and their mixtures, of several organic acids, and of ammonium and potassium hydroxide was studied. It has been shown that as the content of tantalum in a material increases its resistance in solutions of oxidizing acids is improved, but it is reduced in solutions of sulfuric and hydrofluoric acids and also in solutions of potassium hydroxide.

External beam radiotherapy synergizes 188Re-liposome against human esophageal cancer xenograft and modulates 188Re-liposome pharmacokinetics

PubMed Central

Chang, Chih-Hsien; Liu, Shin-Yi; Chi, Chih-Wen; Yu, Hsiang-Lin; Chang, Tsui-Jung; Tsai, Tung-Hu; Lee, Te-Wei; Chen, Yu-Jen

2015-01-01

External beam radiotherapy (EBRT) treats gross tumors and local microscopic diseases. Radionuclide therapy by radioisotopes can eradicate tumors systemically. Rhenium 188 (188Re)-liposome, a nanoparticle undergoing clinical trials, emits gamma rays for imaging validation and beta rays for therapy, with biodistribution profiles preferential to tumors. We designed a combinatory treatment and examined its effects on human esophageal cancer xenografts, a malignancy with potential treatment resistance and poor prognosis. Human esophageal cancer cell lines BE-3 (adenocarcinoma) and CE81T/VGH (squamous cell carcinoma) were implanted and compared. The radiochemical purity of 188Re-liposome exceeded 95%. Molecular imaging by NanoSPECT/CT showed that BE-3, but not CE81T/VGH, xenografts could uptake the 188Re-liposome. The combination of EBRT and 188Re-liposome inhibited tumor regrowth greater than each treatment alone, as the tumor growth inhibition rate was 30% with EBRT, 25% with 188Re-liposome, and 53% with the combination treatment at 21 days postinjection. Combinatory treatment had no additive adverse effects and significant biological toxicities on white blood cell counts, body weight, or liver and renal functions. EBRT significantly enhanced the excretion of 188Re-liposome into feces and urine. In conclusion, the combination of EBRT with 188Re-liposome might be a potential treatment modality for esophageal cancer. PMID:26056445

[Short-term curative effects of Tantalum rod treatment in early avascular necrosis].

PubMed

Ye, Fu-Sheng; Ni, Zhe-Ji; Chu, Xiao-Bing; He, Bang-Jian; Li, Ju; Tong, Pei-Jian

2013-08-01

To explore the recent clinical curative effect of Tantalum rod in treating the early avascular necrosis. From January 2008 to November 2008, the 25 patients (39 hips) with early avascular necrosis accepted tantalum rod placement and included 9 males (11 hips) and 16 females (28 hips) with an average age of 37 years old ranging from 18 to 74 years old. Four patients (6 hips) caused by Alcoholic, 6 patients (8 hips) by hormone, 2 cases (2 hips) by traumatic, 13 cases (23 hips) by idiopathic. Steinberg preoperative stage involved 7 hips in period I, 24 hips in period II, 8 hips in period III. Curative effect analysis included preoperative and postoperative Harris score, radiographic changes and hip replacement for follow-up to accept the end of the femoral head survival rate. All patients were followed up for 6 to 47 months (averaged 37.4 months). All 12 hips imaging appeard progress,including tantalum rod exit in 1 hip, hip hemiarthroplasty collapse in 3 hips, the area increased to avascular necrosis in 8 hips. Six hips accepted total hip replacement, including imaging progress in 5 hips (41.7%, 5/12), no imaging progress in 1 hip (3.7%,1/27). All hips' Kaplan-Meier survival curves showed 6-month survival rate was (97.4 +/- 2.5)% after tantalum stick insertion, 1-year survival rate was (94.7 +/- 3.6), and 2-year survival rate was (88.6 +/- 5.4)%, 3-year survival rate was (72.5 +/- 11.2). It is effective for treatment of avascular necrosis of femoral head in Steinberg I and II by Tantalum rod, and it can effectively relieve femoral head replacement time.

Addition of oxygen to and distribution of oxides in tantalum alloy T-111 at low concentrations

NASA Technical Reports Server (NTRS)

Stecura, S.

1975-01-01

Oxygen was added at 820 and 990 C at an oxygen pressure of about .0003 torr. The technique permitted predetermined and reproducible oxygen doping of the tantalum alloy (T-111). Based on the temperature dependency of the doping reaction, it was concluded that the initial rates of oxygen pickup are probably controlled by solution of oxygen into the T-111 lattice. Although hafnium oxides are more stable than those of tantalum or tungsten, analyses of extracted residues indicate that the tantalum and tungsten oxides predominate in the as-doped specimens, presumably because of the higher concentrations of tantalum and tungsten in the alloy. However, high-temperature annealing promotes gettering of dissolved oxygen and oxygen from other oxides to form hafnium oxides. Small amounts of tantalum and tungsten oxides were still present after high temperature annealing. Tungsten oxide (WO3) volatilizes slightly from the surface of T-111 at 990 C but not at 820 C. The vaporization of WO3 has no apparent effect on the doping reaction.

The effects of argon ion bombardment on the corrosion resistance of tantalum

NASA Astrophysics Data System (ADS)

Ramezani, A. H.; Sari, A. H.; Shokouhy, A.

2017-02-01

Application of ion beam has been widely used as a surface modification method to improve surface properties. This paper investigates the effect of argon ion implantation on surface structure as well as resistance against tantalum corrosion. In this experiment, argon ions with energy of 30 keV and in doses of 1 × 1017-10 × 1017 ions/cm2 were used. The surface bombardment with inert gases mainly produces modified topography and morphology of the surface. Atomic Force Microscopy was also used to patterned the roughness variations prior to and after the implantation phase. Additionally, the corrosion investigation apparatus wear was applied to compare resistance against tantalum corrosion both before and after ion implantation. The results show that argon ion implantation has a substantial impact on increasing resistance against tantalum corrosion. After the corrosion test, scanning electron microscopy (SEM) analyzed the samples' surface morphologies. In addition, the elemental composition is characterized by energy-dispersive X-ray (EDX) analysis. The purpose of this paper was to obtain the perfect condition for the formation of tantalum corrosion resistance. In order to evaluate the effect of the ion implantation on the corrosion behavior, potentiodynamic tests were performed. The results show that the corrosion resistance of the samples strongly depends on the implantation doses.

An exploration in mineral supply chain mapping using tantalum as an example

USGS Publications Warehouse

Soto-Viruet, Yadira; Menzie, W. David; Papp, John F.; Yager, Thomas R.

2013-01-01

This report uses the supply chain of tantalum (Ta) to investigate the complexity of mineral and metal supply chains in general and show how they can be mapped. A supply chain is made up of all the manufacturers, suppliers, information networks, and so forth, that provide the materials and parts that go into making up a final product. The mineral portion of the supply chain begins with mineral material in the ground (the ore deposit); extends through a series of processes that include mining, beneficiation, processing (smelting and refining), semimanufacture, and manufacture; and continues through transformation of the mineral ore into concentrates, refined mineral commodities, intermediate forms (such as metals and alloys), component parts, and, finally, complex products. This study analyses the supply chain of tantalum beginning with minerals in the ground to many of the final goods that contain tantalum.

STUDIES ON ANALYTICAL METHODS FOR TRACE ELEMENTS IN METALS BY USING RADIOACTIVE ISOTOPE. III. DETERMINATION OF TANTALUM BY MEANS OF ISOTOPE DILUTION METHOD

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

Amano, H.

1959-10-01

The determination of tantalum by the isotope dilution method in the presence of niobium was investigated by the use of the radioisotope Ta/sup 185/. Tantalum was separated from niobium as tantalum-tannin precipitate under the optimum conditions of a pH of 1.9 to 2.5 and a tantalum/niobium ratio of up to 1/ 50. If niobium was present in amounts 100 times or more that of tantalum, reprecipitation was needed. The reciprocal of the specific activity of tanthlum pentoxide precipitate was in a linear relation to the change in the amount of tantalum added. The recommended method gave an accurate result inmore » the determination of tantalum in steal. (auth)« less

Thermocouples of tantalum and rhenium alloys for more stable vacuum-high temperature performance

NASA Technical Reports Server (NTRS)

Morris, J. F. (Inventor)

1977-01-01

Thermocouples of the present invention provide stability and performance reliability in systems involving high temperatures and vacuums by employing a bimetallic thermocouple sensor wherein each metal of the sensor is selected from a group of metals comprising tantalum and rhenium and alloys containing only those two metals. The tantalum, rhenium thermocouple sensor alloys provide bare metal thermocouple sensors having advantageous vapor pressure compatibilities and performance characteristics. The compatibility and physical characteristics of the thermocouple sensor alloys of the present invention result in improved emf, temperature properties and thermocouple hot junction performance. The thermocouples formed of the tantalum, rhenium alloys exhibit reliability and performance stability in systems involving high temperatures and vacuums and are adaptable to space propulsion and power systems and nuclear environments.

7 CFR 4279.188-4279.199 - [Reserved

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 15 2012-01-01 2012-01-01 false [Reserved] 4279.188-4279.199 Section 4279.188-4279.199 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE... Loans §§ 4279.188-4279.199 [Reserved] ...

7 CFR 4279.188-4279.199 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 15 2010-01-01 2010-01-01 false [Reserved] 4279.188-4279.199 Section 4279.188-4279.199 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE... Loans §§ 4279.188-4279.199 [Reserved] ...

7 CFR 4279.188-4279.199 - [Reserved

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 15 2011-01-01 2011-01-01 false [Reserved] 4279.188-4279.199 Section 4279.188-4279.199 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE... Loans §§ 4279.188-4279.199 [Reserved] ...

7 CFR 4279.188-4279.199 - [Reserved

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 15 2013-01-01 2013-01-01 false [Reserved] 4279.188-4279.199 Section 4279.188-4279.199 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE... Loans §§ 4279.188-4279.199 [Reserved] ...

7 CFR 4279.188-4279.199 - [Reserved

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 15 2014-01-01 2014-01-01 false [Reserved] 4279.188-4279.199 Section 4279.188-4279.199 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE... Loans §§ 4279.188-4279.199 [Reserved] ...

Tantalum capacitor behavior under fast transient overvoltages. [circuit protection against lightning

NASA Technical Reports Server (NTRS)

Zill, J. A.; Castle, K. D.

1974-01-01

Tantalum capacitors were tested to determine failure time when subjected to short-duration, high-voltage surges caused by lightning strikes. Lightning is of concern to NASA because of possible damage to critical spacecraft circuits. The test was designed to determine the minimum time for tantalum capacitor failure and the amount of overvoltage a capacitor could survive, without permanent damage, in 100 microseconds. All tested exhibited good recovery from the transient one-shot pulses with no failure at any voltage, forward or reverse, in less than 25 microseconds.

SU-E-J-201: Position Verification in Breast Cancer Radiotherapy Using Tantalum Clips in the Lumpectomy Cavity

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

Santvoort, J van; Van der Drift, M; Kuipers, J

2014-06-01

Purpose: To find out whether tantalum surgical clips can be used for online position verification in treatment of the lumpectomy cavity (LC) in breast cancer patients. Tantalum is a high density metal that could be visible on Electronic Portal Images (EPIs) and be an affordable alternative to gold markers. Clips are considered more representative for the LC position than nearby bony structures. Methods: In twelve patients the surgeon had placed 2 to 5 tantalum clips in the LC. The AP and lateral fields used for portal imaging, were adapted. In doing so, both bony structures and tantalum clips were visiblemore » on EPIs. The following analyses were performed:1. Image degradation, with respect to delineating the CTV, of the axial CT slices by artefacts because of the tantalum clips was evaluated by a radiation oncologist;2. The visibility of the tantalum clips on the EPIs was evaluated by four radiation therapists (RTTs);3. Bony anatomy and tantalum clip matches were performed on the same images independently by two observers. Results: 1. Delineation of the CTV by the radiation oncologist was not hampered by CT image artefacts because of the clips.2. The mean score for visibility of the clips on the EPIs, analysed by the four RTTs, was 5.6 on a scale of 10 (range 3.9 – 8.0).3. In total 12 patients with 16 fractions each were analysed. The differences between clip match and bone match are significant with a mean vector length of 5.2 mm (SD 1.9 mm) for the difference. Conclusion: Results of matches on tantalum clips as compared to matches on bony structures differ substantially. Therefore clip matches can result in smaller CTV to PTV margins than bone matches. Visibility of the clips on EPIs is sufficient, so they can be an alternative to gold markers.« less

37 CFR 2.188-2.189 - [Reserved

Code of Federal Regulations, 2013 CFR

2013-07-01

... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false [Reserved] 2.188-2.189 Section 2.188-2.189 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Trademark Cases §§ 2.188-2.189 [Reserved] ...

37 CFR 2.188-2.189 - [Reserved

Code of Federal Regulations, 2011 CFR

2011-07-01

... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false [Reserved] 2.188-2.189 Section 2.188-2.189 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Trademark Cases §§ 2.188-2.189 [Reserved] ...

37 CFR 2.188-2.189 - [Reserved

Code of Federal Regulations, 2012 CFR

2012-07-01

... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false [Reserved] 2.188-2.189 Section 2.188-2.189 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Trademark Cases §§ 2.188-2.189 [Reserved] ...

37 CFR 2.188-2.189 - [Reserved

Code of Federal Regulations, 2014 CFR

2014-07-01

... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false [Reserved] 2.188-2.189 Section 2.188-2.189 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Trademark Cases §§ 2.188-2.189 [Reserved] ...

188Re(V) Nitrido Radiopharmaceuticals for Radionuclide Therapy

PubMed Central

Boschi, Alessandra; Martini, Petra; Uccelli, Licia

2017-01-01

The favorable nuclear properties of rhenium-188 for therapeutic application are described, together with new methods for the preparation of high yield and stable 188Re radiopharmaceuticals characterized by the presence of the nitride rhenium core in their final chemical structure. 188Re is readily available from an 188W/188Re generator system and a parallelism between the general synthetic procedures applied for the preparation of nitride technetium-99m and rhenium-188 theranostics radiopharmaceuticals is reported. Although some differences between the chemical characteristics of the two metallic nitrido fragments are highlighted, it is apparent that the same general procedures developed for the labelling of biologically active molecules with technetium-99m can be applied to rhenium-188 with minor modification. The availability of these chemical strategies, that allow the obtainment, in very high yield and in physiological condition, of 188Re radiopharmaceuticals, gives a new attractive prospective to employ this radionuclide for therapeutic applications. PMID:28106830

188Re(V) Nitrido Radiopharmaceuticals for Radionuclide Therapy.

PubMed

Boschi, Alessandra; Martini, Petra; Uccelli, Licia

2017-01-19

The favorable nuclear properties of rhenium-188 for therapeutic application are described, together with new methods for the preparation of high yield and stable 188 Re radiopharmaceuticals characterized by the presence of the nitride rhenium core in their final chemical structure. 188 Re is readily available from an 188 W/ 188 Re generator system and a parallelism between the general synthetic procedures applied for the preparation of nitride technetium-99m and rhenium-188 theranostics radiopharmaceuticals is reported. Although some differences between the chemical characteristics of the two metallic nitrido fragments are highlighted, it is apparent that the same general procedures developed for the labelling of biologically active molecules with technetium-99m can be applied to rhenium-188 with minor modification. The availability of these chemical strategies, that allow the obtainment, in very high yield and in physiological condition, of 188 Re radiopharmaceuticals, gives a new attractive prospective to employ this radionuclide for therapeutic applications.

The application of porous tantalum cylinder to the repair of comminuted bone defects: a study of rabbit firearm injuries

PubMed Central

Ren, Bo; Zhai, Zhenbo; Guo, Kai; Liu, Yanpu; Hou, Weihuan; Zhu, Qingsheng; Zhu, Jinyu

2015-01-01

The aim of this study is to investigate the effect of porous tantalum material in repair tibial defects caused by firearm injuries in a rabbit model. A multifunctional biological impact machine was used to establish a rabbit tibial defect model of firearm injury. Porous tantalum rods were processed into a hollow cylinder. Kirschner wires were used for intramedullary fixation. We compared the differences of the bone ingrowth of the porous tantalum material by gross observations, X-rays and histological evaluations. The radiographic observations revealed that fibrous tissue covered the material surface after 4 weeks, and periosteal reactions and new bone callus extending materials appeared after 8 weeks. After 16 weeks, the calluses of the firearm injury group were completely wrapped around a porous tantalum material. The group with the highest Lane-Sandhu X-rays cores was the firearm injury and tantalum implant group, and the blank control group exhibited the lowest scores. The histological evaluations revealed that the presence of new bone around the biomaterial had grown into the porous tantalum. By the 16th week, the areas of bone tissue of the firearm injury group was significant higher than that of non-firearm injury group (P<0.05). The comminuted fractures treated with tantalum cylinders exhibited greater bone ingrowth in the firearm injury group. In conditions of firearm injuries, the porous tantalum biomaterial exhibited bone ingrowth that was beneficial to the treatment of bone defects. PMID:26131078

12 CFR 303.188-303.199 - [Reserved

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 4 2011-01-01 2011-01-01 false [Reserved] 303.188-303.199 Section 303.188-303.199 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking §§ 303.188-303.199 [Reserved] ...

12 CFR 303.188-303.199 - [Reserved

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 5 2014-01-01 2014-01-01 false [Reserved] 303.188-303.199 Section 303.188-303.199 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking §§ 303.188-303.199 [Reserved] ...

12 CFR 303.188-303.199 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 4 2010-01-01 2010-01-01 false [Reserved] 303.188-303.199 Section 303.188-303.199 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking §§ 303.188-303.199 [Reserved] ...

12 CFR 303.188-303.199 - [Reserved

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 5 2013-01-01 2013-01-01 false [Reserved] 303.188-303.199 Section 303.188-303.199 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking §§ 303.188-303.199 [Reserved] ...

12 CFR 303.188-303.199 - [Reserved

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 5 2012-01-01 2012-01-01 false [Reserved] 303.188-303.199 Section 303.188-303.199 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION PROCEDURE AND RULES OF PRACTICE FILING PROCEDURES International Banking §§ 303.188-303.199 [Reserved] ...

Transition of dislocation glide to shear transformation in shocked tantalum

DOE PAGES

Hsiung, Luke L.; Campbell, Geoffrey H.

2017-02-28

A TEM study of pure tantalum and tantalum-tungsten alloys explosively shocked at a peak pressure of 30 GPa (strain rate: ~1 x 10 4 sec -1) is presented. While no ω (hexagonal) phase was found in shock-recovered pure Ta and Ta-5W that contain mainly a low-energy cellular dislocation structure, shock-induced ω phase was found to form in Ta-10W that contains evenly distributed dislocations with a stored dislocation density higher than 1 x 10 12 cm -2. The TEM results clearly reveal that shock-induced α (bcc) → ω (hexagonal) shear transformation occurs when dynamic recovery reactions which lead the formation low-energymore » cellular dislocation structure become largely suppressed in Ta-10W shocked under dynamic (i.e., high strain-rate and high-pressure) conditions. A novel dislocation-based mechanism is proposed to rationalize the transition of dislocation glide to twinning and/or shear transformation in shock-deformed tantalum. Lastly, twinning and/or shear transformation take place as an alternative deformation mechanism to accommodate high-strain-rate straining when the shear stress required for dislocation multiplication exceeds the threshold shear stresses for twinning and/or shear transformation.« less

50 CFR 300.188 - Ports of entry.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 11 2014-10-01 2014-10-01 false Ports of entry. 300.188 Section 300.188 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS International Trade Documentation and Tracking Programs for Highly Migratory Species § 300.188 Ports of entry...

50 CFR 300.188 - Ports of entry.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 11 2012-10-01 2012-10-01 false Ports of entry. 300.188 Section 300.188 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS International Trade Documentation and Tracking Programs for Highly Migratory Species § 300.188 Ports of entry...

46 CFR 188.35-5 - Where obtainable.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Where obtainable. 188.35-5 Section 188.35-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-5 Where obtainable. (a) The standards established...

50 CFR 300.188 - Ports of entry.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 11 2013-10-01 2013-10-01 false Ports of entry. 300.188 Section 300.188 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS International Trade Documentation and Tracking Programs for Highly Migratory Species § 300.188 Ports of entry...

46 CFR 188.35-5 - Where obtainable.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Where obtainable. 188.35-5 Section 188.35-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-5 Where obtainable. (a) The standards established...

46 CFR 188.35-5 - Where obtainable.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Where obtainable. 188.35-5 Section 188.35-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-5 Where obtainable. (a) The standards established...

46 CFR 188.35-5 - Where obtainable.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Where obtainable. 188.35-5 Section 188.35-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-5 Where obtainable. (a) The standards established...

46 CFR 188.35-5 - Where obtainable.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Where obtainable. 188.35-5 Section 188.35-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-5 Where obtainable. (a) The standards established...

High-acoustic-impedance tantalum oxide layers for insulating acoustic reflectors.

PubMed

Capilla, Jose; Olivares, Jimena; Clement, Marta; Sangrador, Jesús; Iborra, Enrique; Devos, Arnaud

2012-03-01

This work describes the assessment of the acoustic properties of sputtered tantalum oxide films intended for use as high-impedance films of acoustic reflectors for solidly mounted resonators operating in the gigahertz frequency range. The films are grown by sputtering a metallic tantalum target under different oxygen and argon gas mixtures, total pressures, pulsed dc powers, and substrate biases. The structural properties of the films are assessed through infrared absorption spectroscopy and X-ray diffraction measurements. Their acoustic impedance is assessed by deriving the mass density from X-ray reflectometry measurements and the acoustic velocity from picosecond acoustic spectroscopy and the analysis of the frequency response of the test resonators.

46 CFR 188.10-69 - Scientific laboratory.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Scientific laboratory. 188.10-69 Section 188.10-69 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-69 Scientific laboratory. This term means...

46 CFR 188.10-69 - Scientific laboratory.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Scientific laboratory. 188.10-69 Section 188.10-69 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-69 Scientific laboratory. This term means...

46 CFR 188.10-75 - Undocumented vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Undocumented vessel. 188.10-75 Section 188.10-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-75 Undocumented vessel. This term means any...

46 CFR 188.10-71 - Scientific personnel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Scientific personnel. 188.10-71 Section 188.10-71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-71 Scientific personnel. This term means...

46 CFR 188.10-67 - Scientific equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Scientific equipment. 188.10-67 Section 188.10-67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-67 Scientific equipment. This term means...

46 CFR 188.10-17 - Combustible liquid.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Combustible liquid. 188.10-17 Section 188.10-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-17 Combustible liquid. This term includes any...

46 CFR 188.10-3 - Approved container.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Approved container. 188.10-3 Section 188.10-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-3 Approved container. This term means a...

46 CFR 188.10-27 - Flammable liquid.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Flammable liquid. 188.10-27 Section 188.10-27 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-27 Flammable liquid. This term includes any...

46 CFR 188.10-1 - Anniversary date.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Anniversary date. 188.10-1 Section 188.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-1 Anniversary date. The term anniversary date...

46 CFR 188.10-75 - Undocumented vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Undocumented vessel. 188.10-75 Section 188.10-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-75 Undocumented vessel. This term means any...

46 CFR 188.10-57 - Portable tank.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Portable tank. 188.10-57 Section 188.10-57 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-57 Portable tank. This phrase means a...

46 CFR 188.10-27 - Flammable liquid.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Flammable liquid. 188.10-27 Section 188.10-27 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-27 Flammable liquid. This term includes any...

46 CFR 188.10-23 - Corrosive liquids.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Corrosive liquids. 188.10-23 Section 188.10-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-23 Corrosive liquids. (a) This term includes...

46 CFR 188.10-71 - Scientific personnel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Scientific personnel. 188.10-71 Section 188.10-71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-71 Scientific personnel. This term means...

27 CFR 9.188 - Horse Heaven Hills.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Horse Heaven Hills. 9.188 Section 9.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.188...

27 CFR 9.188 - Horse Heaven Hills.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Horse Heaven Hills. 9.188 Section 9.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.188...

46 CFR 188.10-67 - Scientific equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Scientific equipment. 188.10-67 Section 188.10-67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-67 Scientific equipment. This term means...

46 CFR 188.10-75 - Undocumented vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Undocumented vessel. 188.10-75 Section 188.10-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-75 Undocumented vessel. This term means any...

46 CFR 188.10-57 - Portable tank.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Portable tank. 188.10-57 Section 188.10-57 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-57 Portable tank. This phrase means a...

46 CFR 188.10-75 - Undocumented vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Undocumented vessel. 188.10-75 Section 188.10-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-75 Undocumented vessel. This term means any...

46 CFR 188.10-17 - Combustible liquid.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Combustible liquid. 188.10-17 Section 188.10-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-17 Combustible liquid. This term includes any...

46 CFR 188.10-57 - Portable tank.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Portable tank. 188.10-57 Section 188.10-57 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-57 Portable tank. This phrase means a...

46 CFR 188.10-57 - Portable tank.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Portable tank. 188.10-57 Section 188.10-57 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-57 Portable tank. This phrase means a...

27 CFR 9.188 - Horse Heaven Hills.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Horse Heaven Hills. 9.188 Section 9.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.188...

46 CFR 188.10-27 - Flammable liquid.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Flammable liquid. 188.10-27 Section 188.10-27 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-27 Flammable liquid. This term includes any...

46 CFR 188.10-27 - Flammable liquid.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Flammable liquid. 188.10-27 Section 188.10-27 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-27 Flammable liquid. This term includes any...

50 CFR 216.188 - Letters of Authorization.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Letters of Authorization. 216.188 Section 216.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... Low Frequency Active (SURTASS LFA sonar) Sonar § 216.188 Letters of Authorization. (a) A Letter of...

46 CFR 188.10-17 - Combustible liquid.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Combustible liquid. 188.10-17 Section 188.10-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-17 Combustible liquid. This term includes any...

46 CFR 188.10-3 - Approved container.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Approved container. 188.10-3 Section 188.10-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-3 Approved container. This term means a...

46 CFR 188.10-23 - Corrosive liquids.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Corrosive liquids. 188.10-23 Section 188.10-23 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-23 Corrosive liquids. (a) This term includes...

46 CFR 188.10-3 - Approved container.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Approved container. 188.10-3 Section 188.10-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-3 Approved container. This term means a...

46 CFR 188.10-57 - Portable tank.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Portable tank. 188.10-57 Section 188.10-57 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-57 Portable tank. This phrase means a...

46 CFR 188.10-69 - Scientific laboratory.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Scientific laboratory. 188.10-69 Section 188.10-69 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-69 Scientific laboratory. This term means...

46 CFR 188.10-71 - Scientific personnel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Scientific personnel. 188.10-71 Section 188.10-71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-71 Scientific personnel. This term means...

46 CFR 188.10-1 - Anniversary date.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Anniversary date. 188.10-1 Section 188.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-1 Anniversary date. The term anniversary date...

46 CFR 188.10-17 - Combustible liquid.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Combustible liquid. 188.10-17 Section 188.10-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-17 Combustible liquid. This term includes any...

46 CFR 188.10-75 - Undocumented vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Undocumented vessel. 188.10-75 Section 188.10-75 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-75 Undocumented vessel. This term means any...

46 CFR 188.10-1 - Anniversary date.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Anniversary date. 188.10-1 Section 188.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-1 Anniversary date. The term anniversary date...

50 CFR 216.188 - Letters of Authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Letters of Authorization. 216.188 Section 216.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... Low Frequency Active (SURTASS LFA sonar) Sonar § 216.188 Letters of Authorization. (a) A Letter of...

46 CFR 188.10-1 - Anniversary date.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Anniversary date. 188.10-1 Section 188.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-1 Anniversary date. The term anniversary date...

46 CFR 188.10-67 - Scientific equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Scientific equipment. 188.10-67 Section 188.10-67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-67 Scientific equipment. This term means...

46 CFR 188.10-67 - Scientific equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Scientific equipment. 188.10-67 Section 188.10-67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-67 Scientific equipment. This term means...

46 CFR 188.10-69 - Scientific laboratory.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Scientific laboratory. 188.10-69 Section 188.10-69 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-69 Scientific laboratory. This term means...

46 CFR 188.10-3 - Approved container.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Approved container. 188.10-3 Section 188.10-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-3 Approved container. This term means a...

46 CFR 188.10-27 - Flammable liquid.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Flammable liquid. 188.10-27 Section 188.10-27 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-27 Flammable liquid. This term includes any...

46 CFR 188.10-67 - Scientific equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Scientific equipment. 188.10-67 Section 188.10-67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-67 Scientific equipment. This term means...

46 CFR 188.10-69 - Scientific laboratory.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Scientific laboratory. 188.10-69 Section 188.10-69 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-69 Scientific laboratory. This term means...

46 CFR 188.10-17 - Combustible liquid.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Combustible liquid. 188.10-17 Section 188.10-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-17 Combustible liquid. This term includes any...

46 CFR 188.10-11 - Chemistry laboratory.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Chemistry laboratory. 188.10-11 Section 188.10-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-11 Chemistry laboratory. This term includes...

46 CFR 188.10-11 - Chemistry laboratory.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Chemistry laboratory. 188.10-11 Section 188.10-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-11 Chemistry laboratory. This term includes...

46 CFR 188.10-11 - Chemistry laboratory.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Chemistry laboratory. 188.10-11 Section 188.10-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-11 Chemistry laboratory. This term includes...

46 CFR 188.10-11 - Chemistry laboratory.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Chemistry laboratory. 188.10-11 Section 188.10-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-11 Chemistry laboratory. This term includes...

46 CFR 188.10-11 - Chemistry laboratory.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Chemistry laboratory. 188.10-11 Section 188.10-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-11 Chemistry laboratory. This term includes...

Effect of Reverse Bias Stress on Leakage Currents and Breakdown Voltages of Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander A.

2011-01-01

The majority of solid tantalum capacitors are produced by high-temperature sintering of a fine tantalum powder around a tantalum wire followed by electrolytic anodization that forms a thin amorphous Ta2O5 dielectric layer and pyrolysis of manganese nitrite on the oxide to create a conductive manganese dioxide electrode. A contact to tantalum wire is used as anode terminal and to the manganese layer as a cathode terminal of the device. This process results in formation of an asymmetric Ta -- Ta2O5 -- MnO2 capacitor that has different characteristics at forward (positive bias applied to tantalum) and reverse (positive bias applied to manganese cathode) voltages. Reverse bias currents might be several orders of magnitude larger than forward leakage currents so I-V characteristics of tantalum capacitors resemble characteristics of semiconductor rectifiers. Asymmetric I-V characteristics of Ta -- anodic Ta2O5 systems have been observed at different top electrode materials including metals, electrolytes, conductive polymers, and manganese oxide thus indicating that this phenomenon is likely related to the specifics of the Ta -- Ta2O5 interface. There have been multiple attempts to explain rectifying characteristics of capacitors employing anodic tantalum pentoxide dielectrics. A brief review of works related to reverse bias (RB) behavior of tantalum capacitors shows that the mechanism of conduction in Ta -- Ta2O5 systems is still not clear and more testing and analysis is necessary to understand the processes involved. If tantalum capacitors behave just as rectifiers, then the assessment of the safe reverse bias operating conditions would be a relatively simple task. Unfortunately, these parts can degrade with time under reverse bias significantly, and this further complicates analysis of the I-V characteristics and establishing safe operating areas of the parts. On other hand, time dependence of reverse currents might provide additional information for investigation of

46 CFR 188.10-31 - Great Lakes.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Great Lakes. 188.10-31 Section 188.10-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-31 Great Lakes. Under this designation shall be included...

46 CFR 188.10-65 - Seagoing barge.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Seagoing barge. 188.10-65 Section 188.10-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-65 Seagoing barge. A seagoing barge is a...

46 CFR 188.10-31 - Great Lakes.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Great Lakes. 188.10-31 Section 188.10-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-31 Great Lakes. Under this designation shall be included...

46 CFR 188.10-65 - Seagoing barge.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Seagoing barge. 188.10-65 Section 188.10-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-65 Seagoing barge. A seagoing barge is a...

46 CFR 188.10-65 - Seagoing barge.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Seagoing barge. 188.10-65 Section 188.10-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-65 Seagoing barge. A seagoing barge is a...

46 CFR 188.10-31 - Great Lakes.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Great Lakes. 188.10-31 Section 188.10-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-31 Great Lakes. Under this designation shall be included...

46 CFR 188.10-49 - Numbered vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

46 CFR 188.10-49 - Numbered vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

46 CFR 188.10-31 - Great Lakes.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Great Lakes. 188.10-31 Section 188.10-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-31 Great Lakes. Under this designation shall be included...

46 CFR 188.10-65 - Seagoing barge.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Seagoing barge. 188.10-65 Section 188.10-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-65 Seagoing barge. A seagoing barge is a...

46 CFR 188.10-65 - Seagoing barge.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Seagoing barge. 188.10-65 Section 188.10-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-65 Seagoing barge. A seagoing barge is a...

46 CFR 188.10-49 - Numbered vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

46 CFR 188.10-49 - Numbered vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

46 CFR 188.10-49 - Numbered vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

46 CFR 188.10-31 - Great Lakes.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Great Lakes. 188.10-31 Section 188.10-31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-31 Great Lakes. Under this designation shall be included...

Clustering of transmutation elements tantalum, rhenium and osmium in tungsten in a fusion environment

NASA Astrophysics Data System (ADS)

You, Yu-Wei; Kong, Xiang-Shan; Wu, Xuebang; Liu, C. S.; Fang, Q. F.; Chen, J. L.; Luo, G.-N.

2017-08-01

The formation of transmutation solute-rich precipitates has been reported to seriously degrade the mechanical properties of tungsten in a fusion environment. However, the underlying mechanisms controlling the formation of the precipitates are still unknown. In this study, first-principles calculations are therefore performed to systemically determine the stable structures and binding energies of solute clusters in tungsten consisting of tantalum, rhenium and osmium atoms as well as irradiation-induced vacancies. These clusters are known to act as precursors for the formation of precipitates. We find that osmium can easily segregate to form clusters even in defect-free tungsten alloys, whereas extremely high tantalum and rhenium concentrations are required for the formation of clusters. Vacancies greatly facilitate the clustering of rhenium and osmium, while tantalum is an exception. The binding energies of vacancy-osmium clusters are found to be much higher than those of vacancy-tantalum and vacancy-rhenium clusters. Osmium is observed to strongly promote the formation of vacancy-rhenium clusters, while tantalum can suppress the formation of vacancy-rhenium and vacancy-osmium clusters. The local strain and electronic structure are analyzed to reveal the underlying mechanisms governing the cluster formation. Employing the law of mass action, we predict the evolution of the relative concentration of vacancy-rhenium clusters. This work presents a microscopic picture describing the nucleation and growth of solute clusters in tungsten alloys in a fusion reactor environment, and thereby explains recent experimental phenomena.

Deposition and characterization of magnetron sputtered bcc tantalum

NASA Astrophysics Data System (ADS)

Patel, Anamika

The goal of this thesis was to provide scientific and technical research results for developing and characterizing tantalum (Ta) coatings on steel substrates deposited by DC magnetron sputtering. Deposition of tantalum on steel is of special interest for the protection it offers to surfaces, e.g. the surfaces of gun barrels against the erosive wear of hot propellant gases and the mechanical damage caused by the motion of launching projectiles. Electro-plated chromium is presently most commonly used for this purpose; however, it is considered to be carcinogenic in its hexavalent form. Tantalum is being investigated as non-toxic alternative to chromium and also because of its superior protective properties in these extreme environments. DC magnetron sputtering was chosen for this investigation of tantalum coatings on steel substrates because it is a versatile industrial proven process for deposition of metals. Sputter deposited Ta films can have two crystallographic structures: (1) body center cubic (bcc) phase, characterized by high toughness and high ductility and (2) a tetragonal beta phase characterized by brittleness and a tendency to fail under stress. It was found in this work that the bcc Ta coatings on steel can be obtained reliably by either of two methods: (1) depositing Ta on a submicron, stoichiometric TaN seed layer reactively sputtered on unheated steel and (2) depositing Ta directly on steel heated above a critical temperature. For argon sputtering gas this critical temperature was found to be 400°C at a pressure of 5 mtorr. With the heavier krypton gas, this critical temperature is reduced to 350°C. X-ray diffraction (XRD) was used to investigate the structure of tantalum and nitride films, and the composition of the nitride films was measured by nuclear reaction analyses (NRA), which were used to study in detail the enhancement of the bcc phase of Ta on steel. The scratch adhesion tests performed with a diamond hemispherical tip of radius 200 mum

Monoclonal Antibodies Radiolabeling with Rhenium-188 for Radioimmunotherapy

PubMed Central

Martini, Petra; Pasquali, Micol

2017-01-01

Rhenium-188, obtained from an alumina-based tungsten-188/rhenium-188 generator, is actually considered a useful candidate for labeling biomolecules such as antibodies, antibody fragments, peptides, and DNAs for radiotherapy. There is a widespread interest in the availability of labeling procedures that allow obtaining 188Re-labeled radiopharmaceuticals for various therapeutic applications, in particular for the rhenium attachment to tumor-specific monoclonal antibodies (Mo)Abs for immunotherapy. Different approaches have been developed in order to obtain 188Re-radioimmunoconjugates in high radiochemical purity starting from the generator eluted [188Re]ReO4−. The aim of this paper is to provide a short overview on 188Re-labeled (Mo)Abs, focusing in particular on the radiolabeling methods, quality control of radioimmunoconjugates, and their in vitro stability for radioimmunotherapy (RIT), with particular reference to the most important contributions published in literature in this topic. PMID:28951872

Monoclonal Antibodies Radiolabeling with Rhenium-188 for Radioimmunotherapy.

PubMed

Uccelli, Licia; Martini, Petra; Pasquali, Micol; Boschi, Alessandra

2017-01-01

Rhenium-188, obtained from an alumina-based tungsten-188/rhenium-188 generator, is actually considered a useful candidate for labeling biomolecules such as antibodies, antibody fragments, peptides, and DNAs for radiotherapy. There is a widespread interest in the availability of labeling procedures that allow obtaining 188 Re-labeled radiopharmaceuticals for various therapeutic applications, in particular for the rhenium attachment to tumor-specific monoclonal antibodies (Mo)Abs for immunotherapy. Different approaches have been developed in order to obtain 188 Re-radioimmunoconjugates in high radiochemical purity starting from the generator eluted [ 188 Re]ReO 4 - . The aim of this paper is to provide a short overview on 188 Re-labeled (Mo)Abs, focusing in particular on the radiolabeling methods, quality control of radioimmunoconjugates, and their in vitro stability for radioimmunotherapy (RIT), with particular reference to the most important contributions published in literature in this topic.

Mineral resource of the month: tantalum

USGS Publications Warehouse

Cunningham, Larry D.

2004-01-01

Tantalum is a metal that is critical to the United States because of its defense-related applications in aircraft, missiles and radio communications. It is ductile, easily fabricated, highly resistant to corrosion by acids, a good conductor of heat and electricity, and has a high melting point. Tantalum’s first commercial usage was as filament material in incandescent electric lamps in the early 1900s.

Tantalum coating of porous carbon scaffold supplemented with autologous bone marrow stromal stem cells for bone regeneration in vitro and in vivo.

PubMed

Wei, Xiaowei; Zhao, Dewei; Wang, Benjie; Wang, Wei; Kang, Kai; Xie, Hui; Liu, Baoyi; Zhang, Xiuzhi; Zhang, Jinsong; Yang, Zhenming

2016-03-01

Porous tantalum metal with low elastic modulus is similar to cancellous bone. Reticulated vitreous carbon (RVC) can provide three-dimensional pore structure and serves as the ideal scaffold of tantalum coating. In this study, the biocompatibility of domestic porous tantalum was first successfully tested with bone marrow stromal stem cells (BMSCs) in vitro and for bone tissue repair in vivo. We evaluated cytotoxicity of RVC scaffold and tantalum coating using BMSCs. The morphology, adhesion, and proliferation of BMSCs were observed via laser scanning confocal microscope and scanning electron microscopy. In addition, porous tantalum rods with or without autologous BMSCs were implanted on hind legs in dogs, respectively. The osteogenic potential was observed by hard tissue slice examination. At three weeks and six weeks following implantation, new osteoblasts and new bone were observed at the tantalum-host bone interface and pores. At 12 weeks postporous tantalum with autologous BMSCs implantation, regenerated trabecular equivalent to mature bone was found in the pore of tantalum rods. Our results suggested that domestic porous tantalum had excellent biocompatibility and could promote new bone formation in vivo. Meanwhile, the osteogenesis of porous tantalum associated with autologous BMSCs was more excellent than only tantalum implantation. Future clinical studies are warranted to verify the clinical efficacy of combined implantation of this domestic porous tantalum associated with autologous BMSCs implantation and compare their efficacy with conventional autologous bone grafting carrying blood vessel in patients needing bone repairing. © 2016 by the Society for Experimental Biology and Medicine.

46 CFR 188.10-9 - Chemical storeroom.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Chemical storeroom. 188.10-9 Section 188.10-9 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-9 Chemical storeroom. This term refers to any compartment specifically constructed or modified for the stowage of chemical stores and so designated and...

46 CFR 188.10-9 - Chemical storeroom.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Chemical storeroom. 188.10-9 Section 188.10-9 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-9 Chemical storeroom. This term refers to any compartment specifically constructed or modified for the stowage of chemical stores and so designated and...

46 CFR 188.10-7 - Chemical stores.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Chemical stores. 188.10-7 Section 188.10-7 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-7 Chemical stores. This term means those chemicals intended for use in the performance of the vessel's scientific activities and is further defined...

46 CFR 188.10-7 - Chemical stores.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Chemical stores. 188.10-7 Section 188.10-7 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-7 Chemical stores. This term means those chemicals intended for use in the performance of the vessel's scientific activities and is further defined...

46 CFR 188.10-9 - Chemical storeroom.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Chemical storeroom. 188.10-9 Section 188.10-9 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-9 Chemical storeroom. This term refers to any compartment specifically constructed or modified for the stowage of chemical stores and so designated and...

46 CFR 188.10-7 - Chemical stores.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Chemical stores. 188.10-7 Section 188.10-7 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-7 Chemical stores. This term means those chemicals intended for use in the performance of the vessel's scientific activities and is further defined...

46 CFR 188.10-7 - Chemical stores.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Chemical stores. 188.10-7 Section 188.10-7 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-7 Chemical stores. This term means those chemicals intended for use in the performance of the vessel's scientific activities and is further defined...

46 CFR 188.10-9 - Chemical storeroom.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Chemical storeroom. 188.10-9 Section 188.10-9 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-9 Chemical storeroom. This term refers to any compartment specifically constructed or modified for the stowage of chemical stores and so designated and...

46 CFR 188.10-9 - Chemical storeroom.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Chemical storeroom. 188.10-9 Section 188.10-9 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-9 Chemical storeroom. This term refers to any compartment specifically constructed or modified for the stowage of chemical stores and so designated and...

46 CFR 188.10-7 - Chemical stores.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Chemical stores. 188.10-7 Section 188.10-7 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-7 Chemical stores. This term means those chemicals intended for use in the performance of the vessel's scientific activities and is further defined...

46 CFR 188.10-3 - Approved container.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Approved container. 188.10-3 Section 188.10-3 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-3 Approved container. This term means a container which is properly labeled, marked and approved by DOT for the commodity which it contains. [CGFR...

46 CFR 188.10-1 - Anniversary date.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Anniversary date. 188.10-1 Section 188.10-1 Shipping... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-1 Anniversary date. The term anniversary date means the day and the month of each year, which corresponds to the date of expiration of the Certificate...

Tantalum coating of porous carbon scaffold supplemented with autologous bone marrow stromal stem cells for bone regeneration in vitro and in vivo

PubMed Central

Wei, Xiaowei; Wang, Benjie; Wang, Wei; Kang, Kai; Xie, Hui; Liu, Baoyi; Zhang, Xiuzhi; Zhang, Jinsong; Yang, Zhenming

2016-01-01

Porous tantalum metal with low elastic modulus is similar to cancellous bone. Reticulated vitreous carbon (RVC) can provide three-dimensional pore structure and serves as the ideal scaffold of tantalum coating. In this study, the biocompatibility of domestic porous tantalum was first successfully tested with bone marrow stromal stem cells (BMSCs) in vitro and for bone tissue repair in vivo. We evaluated cytotoxicity of RVC scaffold and tantalum coating using BMSCs. The morphology, adhesion, and proliferation of BMSCs were observed via laser scanning confocal microscope and scanning electron microscopy. In addition, porous tantalum rods with or without autologous BMSCs were implanted on hind legs in dogs, respectively. The osteogenic potential was observed by hard tissue slice examination. At three weeks and six weeks following implantation, new osteoblasts and new bone were observed at the tantalum–host bone interface and pores. At 12 weeks postporous tantalum with autologous BMSCs implantation, regenerated trabecular equivalent to mature bone was found in the pore of tantalum rods. Our results suggested that domestic porous tantalum had excellent biocompatibility and could promote new bone formation in vivo. Meanwhile, the osteogenesis of porous tantalum associated with autologous BMSCs was more excellent than only tantalum implantation. Future clinical studies are warranted to verify the clinical efficacy of combined implantation of this domestic porous tantalum associated with autologous BMSCs implantation and compare their efficacy with conventional autologous bone grafting carrying blood vessel in patients needing bone repairing. PMID:26843518

Antimicrobial activity of tantalum oxide coatings decorated with Ag nanoparticles

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

Cao, Huiliang, E-mail: hlc@mail.sic.ac.cn; Meng, Fanhao; Liu, Xuanyong, E-mail: xyliu@mail.sic.ac.cn

Silver plasma immersion ion implantation was used to decorate silver nanoparticles (Ag NPs) on tantalum oxide (TO) coatings. The coatings acted against bacterial cells (Staphylococcus epidermidis) in the dark by disrupting their integrity. The action was independent of silver release and likely driven by the electron storage capability of the Schottky barriers established at the interfaces between Ag NPs and the TO support. Moreover, no apparent side effect on the adhesion and differentiation of rat bone mesenchymal stem cells was detected when using Ag NPs-modified TO coatings. These results demonstrate that decoration of tantalum oxide using Ag NPs could bemore » a promising procedure for improving the antibacterial properties for orthopedic and dental implants.« less

Application of pyrolysis to recycling organics from waste tantalum capacitors.

PubMed

Niu, Bo; Chen, Zhenyang; Xu, Zhenming

2017-08-05

Tantalum capacitors (TCs) are widely used in electronic appliances. The rapid replacement of electronic products results in generating large amounts of waste TCs (WTCs). WTCs, rich in valuable tantalum, are considered as high quality tantalum resources for recycling. However, environmental pollution will be caused if the organics of WTCs were not properly disposed. Therefore, effectively recycling the organics of WTCs is significant for recovering the valuable parts. This study proposed an argon (Ar) pyrolysis process to recycle the organics from WTCs. The organic decomposition kinetic was first analyzed by thermogravimetry. The results showed that the organics were decomposed in two major steps and the average activation energy was calculated to 234kJ/mol. Then, the suitable pyrolysis parameters were determined as 550°C, 30min and 100ml/min. The organics were effectively decomposed and converted to oils (mainly contained phenol homologs and benzene homologs) and gases (some hydrocarbon). These pyrolysis products could be reutilized as energy sources. Moreover, based on the products and bond energy theory, the pyrolysis mechanisms of the organics were also discussed. Finally, a reasonable technological process for products utilization was presented. This study contributes to the efficient recycling the organics before valuable material recovery from WTCs. Copyright © 2017 Elsevier B.V. All rights reserved.

Achieving surface chemical and morphologic alterations on tantalum by plasma electrolytic oxidation.

PubMed

Goularte, Marcelo Augusto Pinto Cardoso; Barbosa, Gustavo Frainer; da Cruz, Nilson Cristino; Hirakata, Luciana Mayumi

2016-12-01

Search for materials that may either replace titanium dental implants or constitute an alternative as a new dental implant material has been widely studied. As well, the search for optimum biocompatible metal surfaces remains crucial. So, the aim of this work is to develop an oxidized surface layer on tantalum using plasma electrolytic oxidation (PEO) similar to those existing on oral implants been marketed today. Cleaned tantalum samples were divided into group 1 (control) and groups 2, 3, and 4 (treated by PEO for 1, 3, and 5 min, respectively). An electrolytic solution diluted in 1-L deionized water was used for the anodizing process. Then, samples were washed with anhydrous ethyl alcohol and dried in the open air. For complete anodic treatment disposal, the samples were immersed in acetone altogether, taken to the ultrasonic tank for 10 min, washed again in distilled water, and finally air-dried. For the scanning electron microscopy (SEM) analysis, all samples were previously coated with gold; the salt deposition analysis was conducted with an energy-dispersive X-ray spectroscopy (EDS) system integrated with the SEM unit. SEM images confirmed the changes on tantalum strips surface according to different exposure times while EDS analysis confirmed increased salt deposition as exposure time to the anodizing process also increased. PEO was able to produce both surface alteration and salt deposition on tantalum strips similar to those existing on oral implants been marketed today.

X-ray analyses of thermally grown and reactively sputtered tantalum oxide films on NiTi alloy

NASA Astrophysics Data System (ADS)

McNamara, Karrina; Tofail, Syed A. M.; Conroy, Derek; Butler, James; Gandhi, Abbasi A.; Redington, Wynette

2012-08-01

Sputter deposition of tantalum (Ta) on the surface of NiTi alloy is expected to improve the alloy's corrosion resistance and biocompatibility. Tantalum is a well-known biomaterial which is not affected by body fluids and is not irritating to human tissue. Here we compare the oxidation chemistry crystal structure evolution of tantalum oxide films grown on NiTi by reactive O2 sputtering and by thermal oxidation of sputter deposited Ta films. The effect of sputtering parameters and post-sputtering treatments on the morphology, oxidation state and crystal structure of the tantalum oxide layer have been investigated by field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The study has found that it may be better to avoid oxidation at and above 600 °C. The study establishes that reactive sputtering in presence of low oxygen mixture yields thicker film with better control of the film quality except that the surface oxidation state of Ta is slightly lower.

Synthesis and characterization of polystyrene embolization particles doped with tantalum oxide nanoparticles for X-ray contrast.

PubMed

Morrison, Rachel; Thompson, James; Bird, Luke; Hill, Mark A; Townley, Helen

2015-08-01

Radiopaque and fluorescent embolic particles have been synthesized and characterised to match the size of vasculature found in tumours to ensure effective occlusion of the vessels. A literature search showed that the majority of vessels surrounding a tumour were less than 50 µm and therefore polydispersed polystyrene particles with a peak size of 50 µm have been synthesised. The embolic particles contain 5-8 nm amorphous tantalum oxide nanoparticles which provide X-ray contrast. Embolic particles containing up to 9.4 wt% tantalum oxide were prepared and showed significant contrast compared to the undoped polystyrene particles. The X-ray contrast of the embolic particles was shown to be linear (R(2) = 0.9) with respect to the concentration of incorporated tantalum nanoparticles. A model was developed which showed that seventy-five 50 µm embolic particles containing 10% tantalum oxide could provide the same contrast as 5 cm of bone. Therefore, the synthesized particles would provide sufficient X-ray contrast to enable visualisation within a tumour.

Intraarterial irradiation with rhenium-188 for inhibition of restenosis after PTCA - strategy and evaluation of Re-188-species for rapid urinary excretion

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

Knapp, F.F. Jr.; Guhlke, S.; Beets, A.L.

1997-05-01

Estimated costs for coronary restenosis therapy after PTCA are > $ 1 billion (U.S.). Radiation is a simple and effective tool for inhibition of neointimal proliferation an important component of restenosis. We propose use of Re-188 (t{sub {1/2}} 16.9 h, 2.1 MeV {beta}), obtained from decay of W-188 (T{sub {1/2}} 69 d). Our alumina-based W-188/Re-188 generator has a shelf-life of several months and we have developed an on-line tandem cation/anion exchange column system to concentrate to > 18.5 BGq/mL. Estimates for targeted regional dose of 8.4 rad/37 MBq/min/mL, which is > 1,400 cGy for about 370 MBq Re-188 for 5more » min. Balloon inflation with Re-188 solutions is a new approach for more uniform vascular dose distribution as an alternative to use of radioactive wires or other linear sources. Rapid urinary excretion kinetics are important in the unlikely event of balloon rupture (<0.1%). We have therefore evaluated relative excretion kinetics of Re-188-perrhenate and -MAG3 in rats; Re-188-perrhenate was obtained from generator elution with 0.9% NaCl and re-188-MAG3 was prepared be reaction of the ligand with Sn(II)-reduced perrhenate. Fischer rats (n=4-5/group) were injected i.v. and urine and feces collected every 2 h for 12 h and then daily for 5 d. Both agents excreted > 90% in urine; biodistribution studies showed low organ uptake with intestines as the major site. Rhenium-188-MAG3 excreted more rapidly (2 h = 59.6{+-}18.5%) then Re-188-MAG3 excreted more rapidly (2 h = 68.3{+-}13.5%) in same model. Both Re-188 species are thus good candidates for balloon inflation. Studies are in progress in a swine model to evaluate the effectiveness of Re-188 for inhibition of restenosis.« less

Effect of the oxygen content in a salt solution on the characteristics of sodium-reduced tantalum powders

NASA Astrophysics Data System (ADS)

Kolosov, V. N.; Orlov, V. M.; Miroshnichenko, M. N.; Prokhorova, T. Yu.; Masloboeva, S. M.; Belyaevskii, A. T.

2009-02-01

The characteristics of the tantalum powders produced by sodium thermal reduction from salt melts based on K2TaF7 and NaCl with various amounts of added oxycompounds K3TaOF6 and K2Ta2O3F6 are studied. At a molar ratio of oxygen to tantalum of 1.25 in the initial melt, capacitor tantalum powders with a specific surface area more than 3 m2/g are produced. The specific capacitance of the anodes made from these powders reaches 58 mC/g.

Crystalline phase-stability of tantalum pentoxide

NASA Astrophysics Data System (ADS)

Walton, Santiago; Padilha, Antonio; Dalpian, Gustavo; Guillén, Jorge; Dalpian's Research Group Collaboration; Grupo de Estado Solido Collaboration; Gritad Collaboration

2013-03-01

Memristive devices are attractive candidates to provide a paradigm change in memory devices fabrication. These new devices would be faster, denser and less power consuming than those available today. However, the mechanism of memristance is not yet well understood. It is believed that a voltage/current-driven phase transition occurs in the material, which leads to significant changes in the device's conductivity. In the particular case of tantalum-oxide-based devices the relevant crystalline phases are still a matter of debate. Some of these phases are not even completely known and there is no agreement about which model best explains the crystallographic results. In this work we have performed ab-initio DFT based calculations to study the structural properties of different phases (and models) of Ta2O5 - the structure which is believed to exist inside Tantalum Oxide based devices. The equations of state for this material were constructed through first principles total energy calculations and we have also calculated the phonon frequencies at Γ. These results show that the most stable phase of this oxide (B-Ta2O5) is in fact composed of octahedral, instead of pentagonal (as L-Ta2O5) or hexagonal (as δ-Ta2O5) bipyramids. Fapesp, CNPq, Capes,CODI-UdeA

Evaluation of the 3D Finite Element Method Using a Tantalum Rod for Osteonecrosis of the Femoral Head

PubMed Central

Shi, Jingsheng; Chen, Jie; Wu, Jianguo; Chen, Feiyan; Huang, Gangyong; Wang, Zhan; Zhao, Guanglei; Wei, Yibing; Wang, Siqun

2014-01-01

Background The aim of this study was to contrast the collapse values of the postoperative weight-bearing areas of different tantalum rod implant positions, fibula implantation, and core decompression model and to investigate the advantages and disadvantages of tantalum rod implantation in different ranges of osteonecrosis in comparison with other methods. Material/Methods The 3D finite element method was used to establish the 3D finite element model of normal upper femur, 3D finite element model after tantalum rod implantation into different positions of the upper femur in different osteonecrosis ranges, and other 3D finite element models for simulating fibula implant and core decompression. Results The collapse values in the weight-bearing area of the femoral head of the tantalum rod implant model inside the osteonecrosis area, implant model in the middle of the osteonecrosis area, fibula implant model, and shortening implant model exhibited no statistically significant differences (p>0.05) when the osteonecrosis range was small (60°). The stress values on the artificial bone surface for the tantalum rod implant model inside the osteonecrosis area and the shortening implant model exhibited statistical significance (p<0.01). Conclusions Tantalum rod implantation into the osteonecrosis area can reduce the collapse values in the weight-bearing area when osteonecrosis of the femoral head (ONFH) was in a certain range, thereby obtaining better clinical effects. When ONFH was in a large range (120°), the tantalum rod implantation inside the osteonecrosis area, shortening implant or fibula implant can reduce the collapse values of the femoral head, as assessed by other methods. PMID:25479830

The effect of tantalum and carbon on the structure/properties of a single crystal nickel-base superalloy. M.S. Thesis. Final Report

NASA Technical Reports Server (NTRS)

Nguyen, H. C.

1984-01-01

The microstructure, phase chemistry, and creep and hot tensile properties were studied as a function of tantalum and carbon levels in Mar-M247 type single crystal alloys. Microstructural studies showed that several types of carbides (MC, M23C6 and M5C) are present in the normal carbon (0.10 wt % C) alloys after heat treatment. In general, the composition of the MC carbides changes from titanium rich to tantalum rich as the tantalum level in the alloy increases. Small M23C6 carbides are present in all alloys. Tungsten rich M6C carbides are also observed in the alloy containing no tantalum. No carbides are present in the low carbon (0.01 wt % C) alloy series. The morphology of gamma prime is observed to be sensitive to heat treatment and tantalum level in the alloy. Cuboidal gamma prime is present in all the as cast structures. After heat treatment, the gamma prime precipitates tend to have a more spheroidal like morphology, and this tendency increases as the tantalum level decreases. On prolonged aging, the gamma prime reverts back to a cuboidal morphology or under stress at high temperatures, forms a rafted structure. The weight fraction and lattice parameter of the spheroidal gamma prime increases with increasing tantalum content. Changes in the phase chemistry of the gamma prime matrix and gamma prime have also been analyzed using phase extraction techniques. The partitioning ratio decreases for tungsten and aluminum and increases for tantalum as the tantalum content increases for both alloy series; no significant changes occur in the partitioning ratios of the other alloying elements. A reduction in secondary creep rate and an increase in rupture time result from increasing the tantalum content and decreasing the carbon level.

Conflict minerals from the Democratic Republic of the Congo: global tantalum processing plants, a critical part of the tantalum supply chain

USGS Publications Warehouse

Papp, John F.

2014-01-01

Post-beneficiation processing plants (generally called smelters and refineries) for 3TG mineral ores and concentrates were identified by company and industry association representatives as being the link in the 3TG mineral supply chain through which these minerals can be traced to their source of origin (mine). The determination of the source of origin is critical to the development of a complete and transparent conflict-free mineral supply chain. Tungsten processing plants were the subject of the first fact sheet in this series published by USGS NMIC in August 2014. Background information about historical conditions and multinational stakeholders’ voluntary due diligence guidance for minerals from conflict-affected and high-risk areas is presented in the tungsten fact sheet. This fact sheet, the second in a series about 3TG minerals, focuses on the tantalum supply chain by listing selected processors that produced tantalum materials commercially worldwide during 2013–14. It does not provide any information regarding the sources of material processed in these facilities.

46 CFR 188.10-59 - Recognized classification society.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Recognized classification society. 188.10-59 Section 188.10-59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-59 Recognized...

46 CFR 188.10-59 - Recognized classification society.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Recognized classification society. 188.10-59 Section 188.10-59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-59 Recognized...

46 CFR 188.10-59 - Recognized classification society.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Recognized classification society. 188.10-59 Section 188.10-59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-59 Recognized...

46 CFR 188.25-1 - Electrical engineering details.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Electrical engineering details. 188.25-1 Section 188.25... GENERAL PROVISIONS General Electrical Engineering Requirements § 188.25-1 Electrical engineering details. (a) The electrical engineering details shall be in accordance with subchapter J (Electrical...

46 CFR 188.25-1 - Electrical engineering details.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Electrical engineering details. 188.25-1 Section 188.25... GENERAL PROVISIONS General Electrical Engineering Requirements § 188.25-1 Electrical engineering details. (a) The electrical engineering details shall be in accordance with subchapter J (Electrical...

46 CFR 188.25-1 - Electrical engineering details.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Electrical engineering details. 188.25-1 Section 188.25... GENERAL PROVISIONS General Electrical Engineering Requirements § 188.25-1 Electrical engineering details. (a) The electrical engineering details shall be in accordance with subchapter J (Electrical...

46 CFR 188.25-1 - Electrical engineering details.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Electrical engineering details. 188.25-1 Section 188.25... GENERAL PROVISIONS General Electrical Engineering Requirements § 188.25-1 Electrical engineering details. (a) The electrical engineering details shall be in accordance with subchapter J (Electrical...

46 CFR 188.25-1 - Electrical engineering details.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Electrical engineering details. 188.25-1 Section 188.25... GENERAL PROVISIONS General Electrical Engineering Requirements § 188.25-1 Electrical engineering details. (a) The electrical engineering details shall be in accordance with subchapter J (Electrical...

Post-elution concentration of (188)Re by an electrochemical method.

PubMed

Chakravarty, Rubel; Dash, Ashutosh; Pillai, M R A; Venkatesh, Meera

2010-12-01

High specific activity (188)Re required for nuclear medicine is mostly obtained from (188)W/(188)Re generators. As the parent radionuclide (188)W is of low specific activity (<185 GBq/g), a relatively large volume of 0.9% saline is required for the elution of (188)Re. Post-elution concentration is needed in order to increase the radioactive concentration of the eluted (188)Re. An electrochemical procedure to concentrate (188)Re suitable for the preparation of radiopharmaceuticals is developed. (188)Re eluted from an alumina generator could be concentrated approximately 100 fold, and it could be used to label DMSA and HEDP with >98% yield. Copyright 2010 Elsevier Ltd. All rights reserved.

A novel tantalum-based sol-gel packed microextraction syringe for highly specific enrichment of phosphopeptides in MALDI-MS applications.

PubMed

Çelikbıçak, Ömür; Atakay, Mehmet; Güler, Ülkü; Salih, Bekir

2013-08-07

A new tantalum-based sol-gel material was synthesized using a unique sol-gel synthesis pathway by PEG incorporation into the sol-gel structure without performing a calcination step. This improved its chemical and physical properties for the high capacity and selective enrichment of phosphopeptides from protein digests in complex biological media. The specificity of the tantalum-based sol-gel material for phosphopeptides was evaluated and compared with tantalum(V) oxide (Ta2O5) in different phosphopeptide enrichment applications. The tantalum-based sol-gel and tantalum(V) oxide were characterized in detail using FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM), and also using a surface area and pore size analyzer. In the characterization studies, the surface morphology, pore volume, crystallinity of the materials and PEG incorporation into the sol-gel structure to produce a more hydrophilic material were successfully demonstrated. The X-ray diffractograms of the two different materials were compared and it was noted that the broad signals of the tantalum-based sol-gel clearly represented the amorphous structure of the sol-gel material, which was more likely to create enough surface area and to provide more accessible tantalum atoms for phosphopeptides to be easily adsorbed when compared with the neat and more crystalline structure of Ta2O5. Therefore, the phosphopeptide enrichment performance of the tantalum-based sol-gels was found to be remarkably higher than the more crystalline Ta2O5 in our studies. Phosphopeptides at femtomole levels could be selectively enriched using the tantalum-based sol-gel and detected with a higher signal-to-noise ratio by matrix-assisted laser desorption/ionization-mass spectrometer (MALDI-MS). Moreover, phosphopeptides in a tryptic digest of non-fat bovine milk as a complex real-world biological sample were retained with higher yield using a tantalum-based sol-gel. Additionally, the sol-gel material

The Protective Effect of Poloxamer-188 on Platelet Functions.

PubMed

Guler, Nil; Abro, Schuharazad; Emanuele, Marty; Iqbal, Omer; Hoppensteadt, Debra; Fareed, Jawed

2017-11-01

Poloxamer-188 (MST-188) is effective in the repair/recovery of damaged cell membranes. MST-188 is a promising agent for protecting blood cell viability. The aim of the study is to test the hypothesis that MST-188 can extend the duration of platelet function. Blood samples were collected from 20 healthy volunteers. MST-188 (10 or 2 mg/mL) containing platelet-rich plasma (PRP) was prepared with 2 procedures. First, PRP prepared from MST-188 added whole blood (WB); second, MST-188 was added to PRP. These were referred to MST-188-WB preparation (WBP) and MST-188-PRP preparation (PRPP), respectively. For control, saline was used in the same manner. Agonist-induced aggregation (AIA) studies were performed at 30, 180, and 300 minutes using Platelet Aggregation Profiler (PAP-8) aggregometer (Bio/Data Corporation, Horsham, Pennsylvania) and Adenosine diphosphate (ADP), arachidonic acid, collagen, and epinephrine as agonists at final concentration of 20 µM, 500 µg/mL, 0.19 mg/mL, and 100 µM, respectively. There was a protective effect of MST-188 on ADP and collagen AIA. At 300 minutes, ADP AIA was found to be 50.2% higher than saline control in 2-mg WBP, 43% at 10-mg PRPP, and 10.4% at 2-mg PRPP. Protective effect of on collagen AIA was 65.9% in 2-mg WBP, 42.74% at 10-mg PRPP, and 11.42% at 2-mg PRPP. In comparison between 30 and 300 minutes, MST-188 showed significant protection in terms of ADP and collagen receptors and for both types of preparations (WBP and PRPP). The protective effects of MST-188 on ADP- and collagen-induced platelet aggregation may contribute to the preservation of platelet functionality upon storage in blood banks.

Effect of Temperature Cycling and Exposure to Extreme Temperatures on Reliability of Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2007-01-01

In this work, results of multiple temperature cycling (TC) (up to 1,000 cycles) of different types of solid tantalum capacitors are analyzed and reported. Deformation of chip tantalum during temperature variations simulating reflow soldering conditions was measured to evaluate the possibility of the pop-corning effect in the parts. To simulate the effect of short-time exposures to solder reflow temperatures on the reliability of tantalum capacitors, several part types were subjected to multiple cycles (up to 100) between room temperature and 240 C with periodical measurements of electrical characteristics of the parts. Mechanisms of degradation caused by temperature cycling and exposure to high temperatures, and the requirements of MIL-PRF-55365 for assessment of the resistance of the parts to soldering heat are discussed.

CONTRIBUTION TO THE GEOCHEMISTRY OF TANTALUM AND NIOBIUM IN THE HYDROTHERMAL-PNEUMATHOLYTIC PROCESS (in Russian)

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

Beus, A.A.; Sitnin, A.A.

1961-01-01

S>Data obtained as a result of geochemical investigations show that tantalum and niobium are typical elements of high-temperature postmagmatic processes (early albitization, greysening) connected with granites. The separation of tantalum and niobium in the hydrothermal-pneumatholytic process (greysening stage), which leads to the concentration of tantalum in albitized and greysenized granites (40 to 100 times compared to the average content in granites) is connected with the different mobility and stability of their acido- complex compounds (in particular fluor- and oxyfluorcomplexes), the existence of which in greysening solutions is suggested. A natural analogy in the behavior of both elements in the processesmore » of postmagmatic metasomatose in granites and granitic pegmatites is suggested. (tr-auth)« less

Early/Late Heterobimetallic Tantalum/Rhodium Species Assembled Through a Novel Bifunctional NHC-OH Ligand.

PubMed

Srivastava, Ravi; Moneuse, Raphaël; Petit, Julien; Pavard, Paul-Alexis; Dardun, Vincent; Rivat, Madleen; Schiltz, Pauline; Solari, Marius; Jeanneau, Erwann; Veyre, Laurent; Thieuleux, Chloé; Quadrelli, Elsje Alessandra; Camp, Clément

2018-03-20

The straightforward synthesis of a new unsymmetrical hydroxy-tethered N-heterocyclic carbene (NHC) ligand, HL, is presented. The free ligand exhibits an unusual OH-carbene hydrogen-bonding interaction. This OH-carbene motif was used to yield 1) the first tantalum complex displaying both a Fischer- and Schrock-type carbene ligand and 2) a unique NHC-based early/late heterobimetallic complex. More specifically, the protonolysis chemistry between the ligand's hydroxy group and imido-alkyl or alkylidene-alkyl tantalum precursor complexes yielded the rare monometallic tantalum-NHC complexes [Ta(XtBu)(L)(CH 2 tBu) 2 ] (X=N, CH), in which the alkoxy-carbene ligand acts as a chelate. In contrast, HL only binds to rhodium through the NHC unit in [Rh(HL)(cod)Cl] (cod=cycloocta-1,5-diene), the hydroxy pendant arm remaining unbound. This bifunctional ligand scaffold successfully promoted the assembly of rhodium/tantalum heterobimetallic complexes upon either 1) the insertion of [Rh(cod)Cl] 2 into the Ta-NHC bond in [Ta(NtBu)(L)(CH 2 tBu) 2 ] or 2) protonolysis between the free hydroxy group in [Rh(HL)(cod)Cl] and one alkyl group in [Ta(NtBu)(CH 2 tBu) 3 ]. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hot pressing of nanocrystalline tantalum using high frequency induction heating and pulse plasma sintering

NASA Astrophysics Data System (ADS)

Jakubowicz, J.; Adamek, G.; Sopata, M.; Koper, J. K.; Siwak, P.

2017-12-01

The paper presents the results of nanocrystalline powder tantalum consolidation using hot pressing. The authors used two different heating techniques during hot pressing: high-frequency induction heating (HFIH) and pulse plasma sintering (PPS). A comparison of the structure, microstructure, mechanical properties and corrosion resistance of the bulk nanocrystalline tantalum obtained in both techniques was performed. The nanocrystalline powder was made to start from the microcrystalline one using the high-energy ball milling process. The nanocrystalline powder was hot-pressed at 1000 °C, whereas, for comparison, the microcrystalline powder was hot pressed up to 1500 °C for proper consolidation. The authors found that during hot pressing, the powder partially reacts with the graphite die covered by boron nitride, which facilitated punches and powder displacement in the die during densification. Tantalum carbide and boride in the nanocrystalline material was found, which can improve the mechanical properties. The hardness of the HFIH and PPS nanocrystalline tantalum was as high as 625 and 615 HV, respectively. The microstructure was more uniform in the PPS nanomaterial. The corrosion resistance in both cases deteriorated, in comparison to the microcrystalline material, while the PPS material corrosion resistance was slightly better than that of the HFIH one.

7 CFR 1.188 - Awards against other agencies.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Awards against other agencies. 1.188 Section 1.188 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Procedures Relating to Awards Under the Equal Access to Justice Act in Proceedings Before the Department General Provisions § 1.188...

7 CFR 1.188 - Awards against other agencies.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 1 2014-01-01 2014-01-01 false Awards against other agencies. 1.188 Section 1.188 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Procedures Relating to Awards Under the Equal Access to Justice Act in Proceedings Before the Department General Provisions § 1.188...

7 CFR 1.188 - Awards against other agencies.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 1 2012-01-01 2012-01-01 false Awards against other agencies. 1.188 Section 1.188 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Procedures Relating to Awards Under the Equal Access to Justice Act in Proceedings Before the Department General Provisions § 1.188...

46 CFR 188.01-3 - Scope of regulations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Scope of regulations. 188.01-3 Section 188.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-3 Scope of regulations. The regulations in this subchapter contain...

7 CFR 1.188 - Awards against other agencies.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Awards against other agencies. 1.188 Section 1.188 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Procedures Relating to Awards Under the Equal Access to Justice Act in Proceedings Before the Department General Provisions § 1.188...

46 CFR 188.01-3 - Scope of regulations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Scope of regulations. 188.01-3 Section 188.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-3 Scope of regulations. The regulations in this subchapter contain...

7 CFR 1.188 - Awards against other agencies.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 1 2011-01-01 2011-01-01 false Awards against other agencies. 1.188 Section 1.188 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Procedures Relating to Awards Under the Equal Access to Justice Act in Proceedings Before the Department General Provisions § 1.188...

46 CFR 188.01-3 - Scope of regulations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Scope of regulations. 188.01-3 Section 188.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-3 Scope of regulations. The regulations in this subchapter contain...

46 CFR 188.01-3 - Scope of regulations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Scope of regulations. 188.01-3 Section 188.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-3 Scope of regulations. The regulations in this subchapter contain...

46 CFR 188.01-3 - Scope of regulations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Scope of regulations. 188.01-3 Section 188.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-3 Scope of regulations. The regulations in this subchapter contain...

46 CFR 188.20-1 - Marine engineering details.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Marine engineering details. 188.20-1 Section 188.20-1... PROVISIONS General Marine Engineering Requirements § 188.20-1 Marine engineering details. (a) The marine engineering details shall be in accordance with Subchapter F (Marine Engineering) of this chapter. ...

46 CFR 188.20-1 - Marine engineering details.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Marine engineering details. 188.20-1 Section 188.20-1... PROVISIONS General Marine Engineering Requirements § 188.20-1 Marine engineering details. (a) The marine engineering details shall be in accordance with Subchapter F (Marine Engineering) of this chapter. ...

46 CFR 188.20-1 - Marine engineering details.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Marine engineering details. 188.20-1 Section 188.20-1... PROVISIONS General Marine Engineering Requirements § 188.20-1 Marine engineering details. (a) The marine engineering details shall be in accordance with Subchapter F (Marine Engineering) of this chapter. ...

46 CFR 188.20-1 - Marine engineering details.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Marine engineering details. 188.20-1 Section 188.20-1... PROVISIONS General Marine Engineering Requirements § 188.20-1 Marine engineering details. (a) The marine engineering details shall be in accordance with Subchapter F (Marine Engineering) of this chapter. ...

46 CFR 188.20-1 - Marine engineering details.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Marine engineering details. 188.20-1 Section 188.20-1... PROVISIONS General Marine Engineering Requirements § 188.20-1 Marine engineering details. (a) The marine engineering details shall be in accordance with Subchapter F (Marine Engineering) of this chapter. ...

The effect of tantalum on the structure/properties of two polycrystalline nickel-base superalloys: B-1900 + Hf MAR-M247. M.S. Thesis, Final Report

NASA Technical Reports Server (NTRS)

Janowski, G. M.

1985-01-01

The microstructure, phase compositions, and phase fractions were studied in conventionally cast B-1900 + Hf and both conventionally cast and directionally solidified MAR-M247 as a function of tantalum concentration. The hot tensile and creep rupture properties of the solutionized and aged MAR-M247-type alloys were also determined as a function of tantalum level. The effects of tantalum on the microstructure and phase compositions of B-1900 + Hf and MAR-M247 (conventionally cast and directionally solidified) were found to be very similar. The addition of tantalum to the as cast and heat treated alloys was shown to cause the partial replacement of the Hf in the MC carbides by Ta, although the degree of replacement was decreased by the solutionizing and aging heat treatment. The gamma prime and minor phase fractions (primarily MC type carbides) both increased approximately linearly with tantalum concentration. The gamma prime phase compositions were relatively insensitive to tantalum variations with the exception of the tantalum and/or hafnium levels. Bulk tantalum additions increased the tantalum, chromium, and cobalt levels of the gamma phase in both alloy series. The increase in the concentrations of the latter two elements in the gamma phase was a result of the decrease in the gamma phase fraction with increasing bulk tantalum concentration and constant gamma/gamma prime partitioning ratio. Tantalum additions increased the yield stress and ultimate tensile strength of the directionally solidified MAR-M247 type alloys and had no significant effect on ductility.

Primary human osteoblasts grow into porous tantalum and maintain an osteoblastic phenotype.

PubMed

Welldon, Katie J; Atkins, Gerald J; Howie, Donald W; Findlay, David M

2008-03-01

Porous tantalum (Ta) has found application in orthopedics, although the interaction of human osteoblasts (HOB) with this material has not been reported. The aim of this study was to investigate the interaction of primary HOB with porous tantalum, using 5-mm thick discs of porous tantalum. Comparison was made with discs of solid tantalum and tissue culture plastic. Confocal microscopy was used to investigate the attachment and growth of cells on porous Ta, and showed that HOB attached successfully to the metal "trabeculae," underwent extensive cell division, and penetrated into the Ta pores. The maturation of HOB on porous Ta was determined in terms of cell expression of the osteoblast phenotypic markers, STRO-1, and alkaline phosphatase. Despite some donor-dependent variation in STRO-1/AlkPhos expression, growth of cells grown on porous Ta either promoted, or did not impede, the maturation of HOB. In addition, the expression of key osteoblastic genes was investigated after 14 days of culture. The relative levels of mRNA encoding osteocalcin, osteopontin and receptor activator of NFkappaB ligand (RANKL) was not different between porous or solid Ta or plastic, although these genes were expressed differently by cells of different donors. However, bone sialoprotein and type I collagen mRNA species showed a decreased expression on porous Ta compared with expression on plastic. No substrate-dependent differences were seen in the extent of in vitro mineralization by HOB. These results indicate that porous Ta is a good substrate for the attachment, growth, and differentiated function of HOB. (c) 2007 Wiley Periodicals, Inc.

46 CFR 188.01-7 - Right of appeal.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Right of appeal. 188.01-7 Section 188.01-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-7 Right of appeal. Any person directly affected by a decision or...

46 CFR 188.10-43 - Liquefied flammable gas.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Liquefied flammable gas. 188.10-43 Section 188.10-43 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-43 Liquefied flammable gas. This term means...

46 CFR 188.15-5 - Design of vessels.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Design of vessels. 188.15-5 Section 188.15-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Equivalents § 188.15-5 Design of vessels. (a) In order not to inhibit design and application the...

46 CFR 188.01-1 - Purpose of regulations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Purpose of regulations. 188.01-1 Section 188.01-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-1 Purpose of regulations. The purpose of the regulations in this...

46 CFR 188.10-43 - Liquefied flammable gas.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Liquefied flammable gas. 188.10-43 Section 188.10-43 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-43 Liquefied flammable gas. This term means...

46 CFR 188.10-41 - Liquefied compressed gas.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Liquefied compressed gas. 188.10-41 Section 188.10-41 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-41 Liquefied compressed gas. This term means...

46 CFR 188.10-43 - Liquefied flammable gas.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Liquefied flammable gas. 188.10-43 Section 188.10-43 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-43 Liquefied flammable gas. This term means...

46 CFR 188.01-7 - Right of appeal.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Right of appeal. 188.01-7 Section 188.01-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-7 Right of appeal. Any person directly affected by a decision or...

46 CFR 188.10-43 - Liquefied flammable gas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Liquefied flammable gas. 188.10-43 Section 188.10-43 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-43 Liquefied flammable gas. This term means...

46 CFR 188.01-7 - Right of appeal.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Right of appeal. 188.01-7 Section 188.01-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-7 Right of appeal. Any person directly affected by a decision or...

46 CFR 188.01-1 - Purpose of regulations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Purpose of regulations. 188.01-1 Section 188.01-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-1 Purpose of regulations. The purpose of the regulations in this...

46 CFR 188.01-7 - Right of appeal.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Right of appeal. 188.01-7 Section 188.01-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-7 Right of appeal. Any person directly affected by a decision or...

46 CFR 188.10-41 - Liquefied compressed gas.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Liquefied compressed gas. 188.10-41 Section 188.10-41 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-41 Liquefied compressed gas. This term means...

46 CFR 188.10-41 - Liquefied compressed gas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Liquefied compressed gas. 188.10-41 Section 188.10-41 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-41 Liquefied compressed gas. This term means...

46 CFR 188.10-43 - Liquefied flammable gas.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Liquefied flammable gas. 188.10-43 Section 188.10-43 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-43 Liquefied flammable gas. This term means...

46 CFR 188.01-7 - Right of appeal.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Right of appeal. 188.01-7 Section 188.01-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-7 Right of appeal. Any person directly affected by a decision or...

46 CFR 188.01-1 - Purpose of regulations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Purpose of regulations. 188.01-1 Section 188.01-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-1 Purpose of regulations. The purpose of the regulations in this...

46 CFR 188.10-41 - Liquefied compressed gas.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Liquefied compressed gas. 188.10-41 Section 188.10-41 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-41 Liquefied compressed gas. This term means...

46 CFR 188.01-1 - Purpose of regulations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Purpose of regulations. 188.01-1 Section 188.01-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-1 Purpose of regulations. The purpose of the regulations in this...

46 CFR 188.10-41 - Liquefied compressed gas.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Liquefied compressed gas. 188.10-41 Section 188.10-41 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-41 Liquefied compressed gas. This term means...

46 CFR 188.01-1 - Purpose of regulations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Purpose of regulations. 188.01-1 Section 188.01-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Authority and Purpose § 188.01-1 Purpose of regulations. The purpose of the regulations in this...

46 CFR 188.15-5 - Design of vessels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Design of vessels. 188.15-5 Section 188.15-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Equivalents § 188.15-5 Design of vessels. (a) In order not to inhibit design and application the...

Leakage Currents and Gas Generation in Advanced Wet Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2015-01-01

Currently, military grade, established reliability wet tantalum capacitors are among the most reliable parts used for space applications. This has been achieved over the years by extensive testing and improvements in design and materials. However, a rapid insertion of new types of advanced, high volumetric efficiency capacitors in space systems without proper testing and analysis of degradation mechanisms might increase risks of failures. The specifics of leakage currents in wet electrolytic capacitors is that the conduction process is associated with electrolysis of electrolyte and gas generation resulting in building up of internal gas pressure in the parts. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. In this work, in Part I, leakages currents in various types of tantalum capacitors have been analyzed in a wide range of voltages, temperatures, and time under bias. Gas generation and the level of internal pressure have been calculated in Part II for different case sizes and different hermeticity leak rates to assess maximal allowable leakage currents. Effects related to electrolyte penetration to the glass seal area have been studied and the possibility of failures analyzed in Part III. Recommendations for screening and qualification to reduce risks of failures have been suggested.

Effect of Mechanical Stresses on Characteristics of Chip Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander A.

2007-01-01

The effect of compressive mechanical stresses on chip solid tantalum capacitors is investigated by monitoring characteristics of different part types under axial and hydrostatic stresses. Depending on part types, an exponential increase of leakage currents was observed when stresses exceeded 10 MPa to 40 MPa. For the first time, reversible variations of leakage currents (up to two orders of magnitude) with stress have been demonstrated. Mechanical stresses did not cause significant changes of AC characteristics of the capacitors, whereas breakdown voltages measured during the surge current testing decreased substantially indicating an increased probability of failures of stressed capacitors in low impedance applications. Variations of leakage currents are explained by a combination of two mechanisms: stress-induced scintillations and stress-induced generation of electron traps in the tantalum pentoxide dielectric.

Heat of combustion of tantalum-tungsten oxide thermite composites

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

Cervantes, Octavio G.; Department of Chemical Engineering and Materials Science, University of California, Davis, CA 95616; Kuntz, Joshua D.

2010-12-15

The heat of combustion of two distinctly synthesized stoichiometric tantalum-tungsten oxide energetic composites was investigated by bomb calorimetry. One composite was synthesized using a sol-gel (SG) derived method in which micrometric-scale tantalum is immobilized in a tungsten oxide three-dimensional nanostructured network structure. The second energetic composite was made from the mixing of micrometric-scale tantalum and commercially available (CA) nanometric tungsten oxide powders. The energetic composites were consolidated using the spark plasma sintering (SPS) technique under a 300 MPa pressure and at temperatures of 25, 400, and 500 C. For samples consolidated at 25 C, the density of the CA compositemore » is 61.65 {+-} 1.07% in comparison to 56.41 {+-} 1.19% for the SG derived composite. In contrast, the resulting densities of the SG composite are higher than the CA composite for samples consolidated at 400 and 500 C. The theoretical maximum density for the SG composite consolidated to 400 and 500 C are 81.30 {+-} 0.58% and 84.42 {+-} 0.62%, respectively. The theoretical maximum density of the CA composite consolidated to 400 and 500 C are 74.54 {+-} 0.80% and 77.90 {+-} 0.79%, respectively. X-ray diffraction analyses showed an increase of pre-reaction of the constituents with an increase in the consolidation temperature. The increase in pre-reaction results in lower stored energy content for samples consolidated to 400 and 500 C in comparison to samples consolidated at 25 C. (author)« less

Use of a Tantalum Liner to Reduce Bore Erosion and Increase Muzzle Velocity in Two-Stage Light Gas Guns

NASA Technical Reports Server (NTRS)

Bogdanoff, David W.

2015-01-01

Muzzle velocities and gun erosion predicted by earlier numerical simulations of two stage light gas guns with steel gun tubes were in good agreement with experimental values. In a subsequent study, simulations of high performance shots were repeated with rhenium (Re) gun tubes. Large increases in muzzle velocity (2 - 4 km/sec) were predicted for Re tubes. In addition, the hydrogen-produced gun tube erosion was, in general, predicted to be zero with Re tubes. Tantalum (Ta) has some mechanical properties superior to those of Re. Tantalum has a lower modulus of elasticity than Re for better force transmission from the refractory metal liner to an underlying thick wall steel tube. Tantalum also has greater ductility than Re for better survivability during severe stress/strain cycles. Also, tantalum has been used as a coating or liner in military powder guns with encouraging results. Tantalum has, however, somewhat inferior thermal properties to those of rhenium, with a lower melting point and lower density and thermal conductivity. The present study was undertaken to see to what degree the muzzle velocity gains of rhenium gun tubes (over steel tubes) could be achieved with tantalum gun tubes. Nine high performance shots were modeled with a new version of our CFD gun code for steel, rhenium and tantalum gun tubes. For all except the highest velocity shot, the results with Ta tubes were nearly identical with those for Re tubes. Even for the highest velocity shot, the muzzle velocity gain over a steel tube using Ta was 82% of the gain obtained using Re. Thus, the somewhat inferior thermal properties of Ta (when compared to those of Re) translate into only very slightly poorer overall muzzle velocity performance. When this fact is combined with the superior mechanical properties of Ta and the encouraging performance of Ta liners/coatings in military powder guns, tantalum is to be preferred over Re as a liner/coating material for two stage light gas guns to increase muzzle

46 CFR 188.15-5 - Design of vessels.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Design of vessels. 188.15-5 Section 188.15-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Equivalents § 188.15-5 Design of vessels. (a) In order not to inhibit design and application the Commandant may accept vessels of unusual, uniqu...

46 CFR 188.15-5 - Design of vessels.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Design of vessels. 188.15-5 Section 188.15-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Equivalents § 188.15-5 Design of vessels. (a) In order not to inhibit design and application the Commandant may accept vessels of unusual, uniqu...

46 CFR 188.15-5 - Design of vessels.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Design of vessels. 188.15-5 Section 188.15-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Equivalents § 188.15-5 Design of vessels. (a) In order not to inhibit design and application the Commandant may accept vessels of unusual, uniqu...

Evaluation of Ferrite Chip Beads as Surge Current Limiters in Circuits with Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2014-01-01

Limiting resistors are currently required to be connected in series with tantalum capacitors to reduce the risk of surge current failures. However, application of limiting resistors decreases substantially the efficiency of the power supply systems. An ideal surge current limiting device should have a negligible resistance for DC currents and high resistance at frequencies corresponding to transients in tantalum capacitors. This work evaluates the possibility of using chip ferrite beads (FB) as such devices. Twelve types of small size FBs from three manufacturers were used to evaluate their robustness under soldering stresses and at high surge current spikes associated with transients in tantalum capacitors. Results show that FBs are capable to withstand current pulses that are substantially greater than the specified current limits. However, due to a sharp decrease of impedance with current, FBs do not reduce surge currents to the required level that can be achieved with regular resistors.

Tantalum-containing catalyst useful for producing alcohols from synthesis gas

DOEpatents

Kinkade, Nancy E.

1991-01-01

A catalyst useful for selectively converting a mixture of carbon monoxide and hydrogen to a mixture of lower alkanols consisting essentially of a mixture of molybdenum sulfide, an alkali metal compound and a tantalum compound.

Tantalum-containing catalyst useful for producing alcohols from synthesis gas

DOEpatents

Kinkade, Nancy E.

1992-01-01

A catalyst useful for selectively converting a mixture of carbon monoxide and hydrogen to a mixture of lower alkanols consisting essentially of a mixture of molybdenum sulfide, an alkali metal compound and a tantalum compound.

Inferring Strength of Tantalum from Hydrodynamic Instability Recovery Experiments

NASA Astrophysics Data System (ADS)

Sternberger, Z.; Maddox, B.; Opachich, Y.; Wehrenberg, C.; Kraus, R.; Remington, B.; Randall, G.; Farrell, M.; Ravichandran, G.

2018-05-01

Hydrodynamic instability experiments allow access to material properties at extreme conditions, where strain rates exceed 105 s-1 and pressures reach 100 GPa. Current hydrodynamic instability experimental methods require in-flight radiography to image the instability growth at high pressure and high strain rate, limiting the facilities where these experiments can be performed. An alternate approach, recovering the sample after loading, allows measurement of the instability growth with profilometry. Tantalum samples were manufactured with different 2D and 3D initial perturbation patterns and dynamically compressed by a blast wave generated by laser ablation. The samples were recovered from peak pressures between 30 and 120 GPa and strain rates on the order of 107 s-1, providing a record of the growth of the perturbations due to hydrodynamic instability. These records are useful validation points for hydrocode simulations using models of material strength at high strain rate. Recovered tantalum samples were analyzed, providing an estimate of the strength of the material at high pressure and strain rate.

46 CFR 188.27-1 - Lifesaving appliances and arrangements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Lifesaving appliances and arrangements. 188.27-1 Section 188.27-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Lifesaving Appliances and Arrangements § 188.27-1 Lifesaving appliances and...

46 CFR 188.05-33 - Scientific personnel-interpretive rulings.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Scientific personnel-interpretive rulings. 188.05-33 Section 188.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-33 Scientific personnel—interpretive rulings. (a...

46 CFR 188.27-1 - Lifesaving appliances and arrangements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Lifesaving appliances and arrangements. 188.27-1 Section 188.27-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Lifesaving Appliances and Arrangements § 188.27-1 Lifesaving appliances and...

46 CFR 188.05-33 - Scientific personnel-interpretive rulings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Scientific personnel-interpretive rulings. 188.05-33 Section 188.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-33 Scientific personnel—interpretive rulings. (a...

46 CFR 188.05-33 - Scientific personnel-interpretive rulings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Scientific personnel-interpretive rulings. 188.05-33 Section 188.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-33 Scientific personnel—interpretive rulings. (a...

46 CFR 188.27-1 - Lifesaving appliances and arrangements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Lifesaving appliances and arrangements. 188.27-1 Section 188.27-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Lifesaving Appliances and Arrangements § 188.27-1 Lifesaving appliances and...

46 CFR 188.27-1 - Lifesaving appliances and arrangements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Lifesaving appliances and arrangements. 188.27-1 Section 188.27-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Lifesaving Appliances and Arrangements § 188.27-1 Lifesaving appliances and...

46 CFR 188.05-33 - Scientific personnel-interpretive rulings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Scientific personnel-interpretive rulings. 188.05-33 Section 188.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-33 Scientific personnel—interpretive rulings. (a...

Synthesis and characterization of Poloxamer 188-grafted heparin copolymer.

PubMed

Tian, Ji-Lai; Zhao, Ying-Zheng; Jin, Zhuo; Lu, Cui-Tao; Tang, Qin-Qin; Xiang, Qi; Sun, Chang-Zheng; Zhang, Lu; Xu, Yan-Yan; Gao, Hui-Sheng; Zhou, Zhi-Cai; Li, Xiao-Kun; Zhang, Ying

2010-07-01

Poloxamer 188 is a safe biocompatible polymer that can be used in protein drug delivery system. In this study, a new heparin-poloxamer 188 conjugate (HP) was synthesized and its physicochemical properties were investigated. HP structure was confirmed by Fourier transform infrared spectroscopy (FTIR) and Hydrogen-1 nuclear magnetic resonance spectroscopy ((1)H-NMR). Content of the conjugated heparin was analyzed using Toluidine Blue. The critical micelle concentration (CMC) of the copolymer was determined by a fluorescence probe technique. The effect of HP on the gelation of poloxamer 188 was characterized by the rheological properties of the HP-poloxamer hydrogels. Solubility and viscosity of HP were also evaluated compared with poloxamer 188. From the results, the solubility of the conjugated heparin was increased compared with free heparin. The content of heparin in HP copolymer was 62.9%. The CMC of HP and poloxamer 188 were 0.483 and 0.743 mg/mL, respectively. The gelation temperature of 0.4 g/mL HP was 43.5 degrees C, whereas that of the same concentration of poloxamer 188 was 37.3 degrees C. With HP content in poloxamer 188 solution increasing, a V-shape change of gelation temperature was observed. Considering the importance of poloxamer 188 in functional material, HP may prove to be a facile temperature-sensitive material for protein drug-targeted therapy.

Upgrading tantalum and niobium oxides content in Bangka tin slag with double leaching

NASA Astrophysics Data System (ADS)

Soedarsono, J. W.; Permana, S.; Hutauruk, J. K.; Adhyputra, R.; Rustandi, A.; Maksum, A.; Widana, K. S.; Trinopiawan, K.; Anggraini, M.

2018-03-01

Tantalum has become one of the 14 types of critical materials where the level of its availability is assumed as the midterm critical metal. Benefits of the element tantalum in the electronics field increased the deficit balance of supply / demand, as more variations of electronic products developed. The tantalum experts calculated the level of availability until 2020. Base on the previous studies, tin slag is a secondary source of tantalum and niobium. This study uses tin slag from Bangka, Indonesia, abbreviated, Bangka Tin Slag (BTS). BTS was roasted, water quenched and sieved, abbreviated BTS-RQS.BTS was roasted, water quenched and sieved, abbreviated BTS-RQS.BTS-RQS was roasted at a temperature 700□C given sample code BTS-R700QS, while roasted at 800°C given sample code BTS-R800QS.A variable leaching experiment on BTS-R700QS was solvent concentration variable and on BTS-R800QS was time variable. The entire residue was characterized by X-Ray Fluorescence (XRF), and the optimum results are on the BTS-R800QS leaching into 5 M NaOH for 20 min followed by 5M HCl for 50 min, with content of Ta2O5 and Nb2O51.56% and 1.11%, respectively. The result of XRF measurement showed was the increasing of TNO content due to the increasing solvent concentration and time of acid leaching. The discussion of thermodynamics this study used was HSC Chemistry 6 as a supporting data.

Evaluation of Polymer Hermetically Sealed Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander A.

2014-01-01

Polymer cathode tantalum capacitors have lower ESR (equivalent series resistance) compared to other types of tantalum capacitors and for this reason have gained popularity in the electronics design community. Their use allows improved performance of power supply systems along with substantial reduction of size and weight of the components used. However, these parts have poor thermal stability and can degrade in humid environments. Polymer hermetically sealed (PHS) capacitors avoid problems related to environmental degradation of molded case parts and can potentially replace current wet and solid hermetically sealed capacitors. In this work, PHS capacitors manufactured per DLA LAM DWG#13030 are evaluated for space applications. Several lots of capacitors manufactured over period from 2010 to 2014 were tested for the consistency of performance, electrical and thermal characteristics, highly accelerated life testing, and robustness under reverse bias and random vibration conditions. Special attention was given to analysis of leakage currents and the effect of long-term high temperature storage on capacitors in as is condition and after hermeticity loss. The results show that PHS capacitors might be especially effective for low-temperature applications or for system requiring a cold start-up. Additional screening and qualification testing have been recommended to assure the necessary quality of capacitors for space projects.

50 CFR 218.188 - Modifications to Letters of Authorization.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Modifications to Letters of Authorization. 218.188 Section 218.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND... Surface Warfare Center Panama City Division § 218.188 Modifications to Letters of Authorization. (a...

46 CFR 188.05-35 - Load lines-interpretive ruling.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Load lines-interpretive ruling. 188.05-35 Section 188.05-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-35 Load lines—interpretive ruling. (a) Certificated vessels shall...

50 CFR 218.188 - Modifications to Letters of Authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Modifications to Letters of Authorization. 218.188 Section 218.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND... Surface Warfare Center Panama City Division § 218.188 Modifications to Letters of Authorization. (a...

46 CFR 188.05-35 - Load lines-interpretive ruling.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Load lines-interpretive ruling. 188.05-35 Section 188.05-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-35 Load lines—interpretive ruling. (a) Certificated vessels shall...

27 CFR 19.188 - Measuring devices and proofing instruments.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Measuring devices and proofing instruments. 19.188 Section 19.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX..., and Security Requirements Measuring and Proofing Equipment Requirements § 19.188 Measuring devices and...

27 CFR 19.188 - Measuring devices and proofing instruments.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Measuring devices and proofing instruments. 19.188 Section 19.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX..., and Security Requirements Measuring and Proofing Equipment Requirements § 19.188 Measuring devices and...

28 CFR 115.188 - Data review for corrective action.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Data review for corrective action. 115.188 Section 115.188 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) PRISON RAPE ELIMINATION ACT NATIONAL STANDARDS Standards for Lockups Data Collection and Review § 115.188 Data review for...

50 CFR 218.188 - Modifications to Letters of Authorization.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Modifications to Letters of Authorization. 218.188 Section 218.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND... Surface Warfare Center Panama City Division § 218.188 Modifications to Letters of Authorization. (a...

27 CFR 19.188 - Measuring devices and proofing instruments.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Measuring devices and proofing instruments. 19.188 Section 19.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX..., and Security Requirements Measuring and Proofing Equipment Requirements § 19.188 Measuring devices and...

28 CFR 115.188 - Data review for corrective action.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Data review for corrective action. 115.188 Section 115.188 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) PRISON RAPE ELIMINATION ACT NATIONAL STANDARDS Standards for Lockups Data Collection and Review § 115.188 Data review for...

46 CFR 188.05-35 - Load lines-interpretive ruling.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Load lines-interpretive ruling. 188.05-35 Section 188.05-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-35 Load lines—interpretive ruling. (a) Certificated vessels shall...

17 CFR 256.188 - Research, development, or demonstration expenditures.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Research, development, or demonstration expenditures. 256.188 Section 256.188 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 4. Deferred Debits § 256.188 Research, development, or...

46 CFR 188.05-35 - Load lines-interpretive ruling.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Load lines-interpretive ruling. 188.05-35 Section 188.05-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-35 Load lines—interpretive ruling. (a) Certificated vessels shall...

28 CFR 115.188 - Data review for corrective action.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Data review for corrective action. 115.188 Section 115.188 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) PRISON RAPE ELIMINATION ACT NATIONAL STANDARDS Standards for Lockups Data Collection and Review § 115.188 Data review for...

46 CFR 188.05-35 - Load lines-interpretive ruling.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Load lines-interpretive ruling. 188.05-35 Section 188.05-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-35 Load lines—interpretive ruling. (a) Certificated vessels shall...

50 CFR 218.188 - Modifications to Letters of Authorization.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Modifications to Letters of Authorization. 218.188 Section 218.188 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND... Surface Warfare Center Panama City Division § 218.188 Modifications to Letters of Authorization. (a...

27 CFR 19.188 - Measuring devices and proofing instruments.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Measuring devices and proofing instruments. 19.188 Section 19.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX..., and Security Requirements Measuring and Proofing Equipment Requirements § 19.188 Measuring devices and...

Tantalum-containing catalyst useful for producing alcohols from synthesis gas

DOEpatents

Kinkade, N.E.

1992-04-07

A catalyst is described which is useful for selectively converting a mixture of carbon monoxide and hydrogen to a mixture of lower alkanols. The catalyst consists essentially of a mixture of molybdenum sulfide, an alkali metal compound and a tantalum compound.

46 CFR 188.10-13 - Coast Guard District Commander.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District Commander...

46 CFR 188.10-13 - Coast Guard District Commander.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District Commander...

46 CFR 188.10-13 - Coast Guard District Commander.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District Commander...

46 CFR 188.10-13 - Coast Guard District Commander.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District Commander...

46 CFR 188.10-13 - Coast Guard District Commander.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District Commander...

46 CFR 188.10-71 - Scientific personnel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... scientific research, or in instructing, or receiving instruction, in oceanography or limnology, and shall not... 46 Shipping 7 2011-10-01 2011-10-01 false Scientific personnel. 188.10-71 Section 188.10-71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL...

46 CFR 188.10-71 - Scientific personnel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... scientific research, or in instructing, or receiving instruction, in oceanography or limnology, and shall not... 46 Shipping 7 2010-10-01 2010-10-01 false Scientific personnel. 188.10-71 Section 188.10-71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL...

37 CFR 2.188-2.189 - [Reserved

Code of Federal Regulations, 2010 CFR

2010-07-01

... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false [Reserved] 2.188-2.189 Section 2.188-2.189 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE, DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES General Information and Correspondence in...

47 CFR 1.88 - Predesignation pleading procedure.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false Predesignation pleading procedure. 1.88 Section... Rules of Practice and Procedure Miscellaneous Proceedings § 1.88 Predesignation pleading procedure. In... staff, in its discretion, may in writing, advise such licensee of the general nature of the...

46 CFR 188.35-1 - Standards to be used.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Standards to be used. 188.35-1 Section 188.35-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-1 Standards to be used. (a) Where in this...

46 CFR 188.35-1 - Standards to be used.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Standards to be used. 188.35-1 Section 188.35-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-1 Standards to be used. (a) Where in this...

46 CFR 188.35-1 - Standards to be used.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Standards to be used. 188.35-1 Section 188.35-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-1 Standards to be used. (a) Where in this...

46 CFR 188.10-39 - Lakes, bays, and sounds.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this...

46 CFR 188.10-39 - Lakes, bays, and sounds.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this...

46 CFR 188.10-39 - Lakes, bays, and sounds.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this...

46 CFR 188.35-1 - Standards to be used.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Standards to be used. 188.35-1 Section 188.35-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS American Bureau of Shipping's Standards § 188.35-1 Standards to be used. (a) Where in this...

46 CFR 188.10-73 - Ships' stores and supplies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Ships' stores and supplies. 188.10-73 Section 188.10-73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-73 Ships' stores and supplies. This term...

46 CFR 188.10-73 - Ships' stores and supplies.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Ships' stores and supplies. 188.10-73 Section 188.10-73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-73 Ships' stores and supplies. This term...

46 CFR 188.10-73 - Ships' stores and supplies.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Ships' stores and supplies. 188.10-73 Section 188.10-73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-73 Ships' stores and supplies. This term...

46 CFR 188.10-73 - Ships' stores and supplies.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Ships' stores and supplies. 188.10-73 Section 188.10-73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-73 Ships' stores and supplies. This term...

46 CFR 188.10-6 - Captain of the Port.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Captain of the Port. 188.10-6 Section 188.10-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-6 Captain of the Port. This term means an...

27 CFR 70.188 - Expense of levy and sale.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Expense of levy and sale. 70.188 Section 70.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Disposition of Property § 70.188 Expense of levy and sale. The...

27 CFR 70.188 - Expense of levy and sale.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Expense of levy and sale. 70.188 Section 70.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Disposition of Property § 70.188 Expense of levy and sale. The...

46 CFR 188.10-6 - Captain of the Port.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Captain of the Port. 188.10-6 Section 188.10-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-6 Captain of the Port. This term means an...

46 CFR 188.10-6 - Captain of the Port.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Captain of the Port. 188.10-6 Section 188.10-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-6 Captain of the Port. This term means an...

46 CFR 188.10-6 - Captain of the Port.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Captain of the Port. 188.10-6 Section 188.10-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-6 Captain of the Port. This term means an...

27 CFR 70.188 - Expense of levy and sale.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Expense of levy and sale. 70.188 Section 70.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Disposition of Property § 70.188 Expense of levy and sale. The...

46 CFR 188.10-6 - Captain of the Port.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Captain of the Port. 188.10-6 Section 188.10-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-6 Captain of the Port. This term means an...

27 CFR 70.188 - Expense of levy and sale.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Expense of levy and sale. 70.188 Section 70.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Disposition of Property § 70.188 Expense of levy and sale. The...

27 CFR 70.188 - Expense of levy and sale.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Expense of levy and sale. 70.188 Section 70.188 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Disposition of Property § 70.188 Expense of levy and sale. The...

46 CFR 154.188 - Membrane tank: Inner hull steel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Hull Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull...

Frequency spectrum of tantalum at temperatures of 293-2300 K

NASA Astrophysics Data System (ADS)

Semenov, V. A.; Kozlov, Zh. A.; Krachun, L.; Mateescu, G.; Morozov, V. M.; Oprea, A. I.; Oprea, K.; Puchkov, A. V.

2010-05-01

The temperature dependence of the frequency spectrum of tantalum in the temperature range from room temperature to 2300 K has been studied for the first time using inelastic slow-neutron scattering. The inelastic slow-neutron scattering spectra have been measured at different temperatures on a DIN-2PI time-of-flight spectrometer installed at the IBR-2 nuclear reactor (Joint Institute for Nuclear Research, Dubna, Russia) with the use of a TS3000K high-temperature thermostat. From the measured spectra, the frequency spectra of the tantalum crystal lattice have been determined at temperatures of 293, 1584, and 2300 K by the iteration method. As the temperature increases, the frequency spectrum, on the whole, is softened and the specific features manifested themselves at room temperature are smoothed. The variations observed have been explained by the increase in the role of the effects of vibration anharmonism at high temperatures.

22 CFR 18.8 - Institution of proceeding.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Institution of proceeding. 18.8 Section 18.8 Foreign Relations DEPARTMENT OF STATE PERSONNEL REGULATIONS CONCERNING POST EMPLOYMENT CONFLICT OF... where time, the nature of the proceeding, or the public interest does not permit, a proceeding will not...

Atomization from a tantalum surface in graphite furnace atomic absorption spectrometry

NASA Astrophysics Data System (ADS)

Gregoire, D. C.; Chakrabarti, C. L.

The mechanism of atom formation of U, V, Mo, Ni, Mn, Cu and Mg atomized from pyrolytic graphite and tantalum metal surfaces has been studied. The mechanism of atom formation for U from a graphite tube atomizer is reported for the first time. The peak absorbance for U and Cu is increased by factors of 59.7 and 2.0, respectively, whereas that of V, Mo and Ni is reduced by several orders of magnitude when they are atomized from a tantalum metal surface. The peak absorbance of Mn and Mg is not appreciably affected by the material of the atomization surface. Interaction of Mn and Mg with the graphite surface and formation of their refractory carbides was found to be negligible. Uranium forms a refractory carbide when heated from a graphite surface.

46 CFR 188.10-45 - Marine inspector or inspector.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Marine inspector or inspector. 188.10-45 Section 188.10... GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-45 Marine inspector or inspector... superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated...

46 CFR 188.10-45 - Marine inspector or inspector.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Marine inspector or inspector. 188.10-45 Section 188.10... GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-45 Marine inspector or inspector... superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated...

46 CFR 188.10-45 - Marine inspector or inspector.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Marine inspector or inspector. 188.10-45 Section 188.10... GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-45 Marine inspector or inspector... superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated...

46 CFR 188.10-45 - Marine inspector or inspector.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Marine inspector or inspector. 188.10-45 Section 188.10... GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-45 Marine inspector or inspector... superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated...

46 CFR 188.10-45 - Marine inspector or inspector.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Marine inspector or inspector. 188.10-45 Section 188.10... GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-45 Marine inspector or inspector... superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated...

46 CFR 188.10-73 - Ships' stores and supplies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Ships' stores and supplies. 188.10-73 Section 188.10-73 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-73 Ships' stores and supplies. This term means any article or substance which is...

46 CFR 154.188 - Membrane tank: Inner hull steel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull... 46 Shipping 5 2013-10-01 2013-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... “Rules for Building and Classing Steel Vessels”, 1981. [CGD 74-289, 44 FR 26009, May 3, 1979, as amended...

46 CFR 154.188 - Membrane tank: Inner hull steel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull... 46 Shipping 5 2014-10-01 2014-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... “Rules for Building and Classing Steel Vessels”, 1981. [CGD 74-289, 44 FR 26009, May 3, 1979, as amended...

46 CFR 154.188 - Membrane tank: Inner hull steel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull... 46 Shipping 5 2011-10-01 2011-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... “Rules for Building and Classing Steel Vessels”, 1981. [CGD 74-289, 44 FR 26009, May 3, 1979, as amended...

46 CFR 154.188 - Membrane tank: Inner hull steel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull... 46 Shipping 5 2012-10-01 2012-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... “Rules for Building and Classing Steel Vessels”, 1981. [CGD 74-289, 44 FR 26009, May 3, 1979, as amended...

46 CFR 188.10-39 - Lakes, bays, and sounds.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this designation shall be included all vessels navigating the waters of any of the lakes, bays, or sounds, other...

46 CFR 188.10-39 - Lakes, bays, and sounds.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this designation shall be included all vessels navigating the waters of any of the lakes, bays, or sounds, other...

2014 NEPP Tasks Update for Ceramic and Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander A.

2014-01-01

Presentation describes recent development in research on MnO2, wet, and polymer tantalum capacitors. Low-voltage failures in multilayer ceramic capacitors and techniques to reveal precious metal electrode (PME) and base metal electrode (BME) capacitors with cracks are discussed. A voltage breakdown technique is suggested to select high quality low-voltage BME ceramic capacitors.

Alkyl group effects on CO insertion into coordinatively unsaturated early-transition-metal alkyls. Preparations and the first structural characterizations of tantalum enolate-O and tantalum. eta. sup 2 -acyl complexes

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

Meyer, T.Y.; Garner, L.R.; Baenziger, N.C.

1990-10-03

Low-pressure carbonylation of the mono(peralkylcyclopentadienyl)tantalum(V) alkyls ({eta}-C{sub 5}Me{sub 4}R)TaR{prime}Cl{sub 3} (R = Me, Et; R{prime} = CH{sub 2}C{sub 6}H{sub 4}-p-Me, CH{sub 2}CMe{sub 3}) yields either the O-bound enolate or the {eta}{sup 2}-acyl as shown by ir/NMR spectroscopy and x-ray diffractometry. The p-tolyl enolate ({eta}-C{sub 5}Me{sub 5})Ta(OCH{double bond}CHC{sub 6}H{sub 4}-p-Me)Cl{sub 3}, derived directly from carbonylation of the tantalum 4-methylbenzyl precursor, is shown to possess a cis configuration in solution and in the solid state. Key structural features from a single-crystal x-ray diffraction study of the tetrahydrofuran-ligated enolate complex are reported. The mechanism of formation of the enolate from carbonylation of themore » 4-methylbenzyl complex is discussed. The previously reported acyl ({eta}-C{sub 5}Me{sub 4}R)Ta(C(O)CH{sub 2}CMe{sub 3})Cl{sub 3} has been reexamined and found to possess a symmetric, strongly distorted {eta}{sup 2}-acyl coordination by solution {sup 1}H NMR spectroscopy and solid-state x-ray diffractometry. The molecular structures of ({eta}-C{sub 5}Me{sub 5})Ta(OCH{double bond}CHC{sub 6}H{sub 4}-p-Me)Cl{sub 3} and ({eta}-C{sub 5}Me{sub 5})Ta(C(O)CH{sub 2}CMe{sub 3})Cl{sub 3}, which are reported here, are the first structural determinations of a tantalum enolate and of a tantalum {eta}{sup 2}-acyl. 41 refs., 2 figs., 8 tabs.« less

Study of surge current effects on solid tantalum capacitors

NASA Technical Reports Server (NTRS)

1980-01-01

Results are presented of a 2,000 hour cycled life test program conducted to determine the effect of short term surge current screening on approximately 47 micron f/volt solid tantalum capacitors. The format provides average values and standard deviations of the parameters, capacitance, dissipation factor, and equivalent series resistance at 120 Hz, 1KHz, abd 40 KHz.

Diffusion-Cooled Tantalum Hot-Electron Bolometer Mixers

NASA Technical Reports Server (NTRS)

Skalare, Anders; McGrath, William; Bumble, Bruce; LeDuc, Henry

2004-01-01

A batch of experimental diffusion-cooled hot-electron bolometers (HEBs), suitable for use as mixers having input frequencies in the terahertz range and output frequencies up to about a gigahertz, exploit the superconducting/normal-conducting transition in a thin strip of tantalum. The design and operation of these HEB mixers are based on mostly the same principles as those of a prior HEB mixer that exploited the superconducting/normal- conducting transition in a thin strip of niobium and that was described elsewhere.

36 CFR 223.188 - Prohibitions against exporting unprocessed Federal timber.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Prohibitions against exporting unprocessed Federal timber. 223.188 Section 223.188 Parks, Forests, and Public Property FOREST... Program § 223.188 Prohibitions against exporting unprocessed Federal timber. No person who acquires...

36 CFR 223.188 - Prohibitions against exporting unprocessed Federal timber.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Prohibitions against exporting unprocessed Federal timber. 223.188 Section 223.188 Parks, Forests, and Public Property FOREST... Program § 223.188 Prohibitions against exporting unprocessed Federal timber. No person who acquires...

36 CFR 223.188 - Prohibitions against exporting unprocessed Federal timber.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Prohibitions against exporting unprocessed Federal timber. 223.188 Section 223.188 Parks, Forests, and Public Property FOREST... Program § 223.188 Prohibitions against exporting unprocessed Federal timber. No person who acquires...

36 CFR 223.188 - Prohibitions against exporting unprocessed Federal timber.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Prohibitions against exporting unprocessed Federal timber. 223.188 Section 223.188 Parks, Forests, and Public Property FOREST... Program § 223.188 Prohibitions against exporting unprocessed Federal timber. No person who acquires...

Electron-ion temperature equilibration in warm dense tantalum

DOE PAGES

Doppner, T; LePape, S.; Ma, T.; ...

2014-11-05

We present measurements of electron-ion temperature equilibration in proton-heated tantalum, under warm dense matter conditions. Our results agree with theoretical predictions for metals calculated using input data from ab initio simulations. Furthermore, the fast relaxation observed in the experiment contrasts with much longer equilibration times found in proton heated carbon, indicating that the energy flow pathways in warm dense matter are far from being fully understood.

Intratumoral Injection of 188Re labeled Cationic Polyethylenimine Conjugates: A Preliminary Report

PubMed Central

Kim, Eun-Mi; Heo, Young-Jun; Moon, Hyung-Bae; Bom, Hee-Seung; Kim, Chang-Guhn

2004-01-01

188Re(Rhenium) is easily obtained from an in-house 188W/188Re generator that is similar to the current 99Mo/99mTc generator, making it very convenient for clinical use. This characteristic makes this radionuclide a promising candidate as a therapeutic agent. Polyethylenimine (PEI) is a cationic polymer and has been used as a gene delivery vector. Positively charged materials interact with cellular blood components, vascular endothelium, and plasma proteins. In this study, the authors investigated whether intratumoral injection of 188Re labeled transferrin (Tf)-PEI conjugates exert the effect of radionuclide therapy against the tumor cells. When the diameters of the Ramos lymphoma (human Burkitt's lymphoma) xenografted tumors reached approximately 1 cm, 3 kinds of 188Re bound compounds (HYNIC-PEI-Tf, HYNIC-PEI, 188Re perrhenate) were injected directly into the tumors. There were increases in the retention of 188Re inside the tumor when PEI was incorporated with 188Re compared to the use of free 188Re. The 188Re HYNIC-Tf-PEI showed the most retention inside the tumor (retention rate=approximately 97%). H&E stain of isolated tumor tissues showed that 188Re labeled HYNIC-PEI-Tf caused extensive tumor necrosis. These results support 188Re HYNIC-PEI-Tf as being a useful radiopharmaceutical agent to treat tumors when delievered by intratumoral injection. PMID:15483337

Response and representation of ductile damage under varying shock loading conditions in tantalum

DOE PAGES

Bronkhorst, C. A.; Gray, III, G. T.; Addessio, F. L.; ...

2016-02-25

The response of polycrystalline metals, which possess adequate mechanisms for plastic deformation under extreme loading conditions, is often accompanied by the formation of pores within the structure of the material. This large deformation process is broadly identified as progressive with nucleation, growth, coalescence, and failure the physical path taken over very short periods of time. These are well known to be complex processes strongly influenced by microstructure, loading path, and the loading profile, which remains a significant challenge to represent and predict numerically. In the current study, the influence of loading path on the damage evolution in high-purity tantalum ismore » presented. Tantalum samples were shock loaded to three different peak shock stresses using both symmetric impact, and two different composite flyer plate configurations such that upon unloading the three samples displayed nearly identical “pull-back” signals as measured via rear-surface velocimetry. While the “pull-back” signals observed were found to be similar in magnitude, the sample loaded to the highest peak stress nucleated a connected field of ductile fracture which resulted in complete separation, while the two lower peak stresses resulted in incipient damage. The damage evolution in the “soft” recovered tantalum samples was quantified using optical metallography, electron-back-scatter diffraction, and tomography. These experiments are examined numerically through the use of a model for shock-induced porosity evolution during damage. The model is shown to describe the response of the tantalum reasonably well under strongly loaded conditions but less well in the nucleation dominated regime. As a result, numerical results are also presented as a function of computational mesh density and discussed in the context of improved representation of the influence of material structure upon macro-scale models of ductile damage.« less

36 CFR 223.188 - Prohibitions against exporting unprocessed Federal timber.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Prohibitions against exporting unprocessed Federal timber. 223.188 Section 223.188 Parks, Forests, and Public Property FOREST... Conservation and Shortage Relief Act of 1990 Program § 223.188 Prohibitions against exporting unprocessed...

Comparative dosimetric evaluation of nanotargeted (188)Re-(DXR)-liposome for internal radiotherapy.

PubMed

Chang, Chih-Hsien; Stabin, Michael G; Chang, Ya-Jen; Chen, Liang-Cheng; Chen, Min-Hua; Chang, Tsui-Jung; Lee, Te-Wei; Ting, Gann

2008-12-01

A dosimetric analysis was performed to evaluate nanoliposomes as carriers of radionuclides ((188)Re-liposomes) and radiochemotherapeutic drugs [(188)Re-doxorubicin (DXR)-liposomes] in internal radiotherapy for colon carcinoma, as evaluated in mice. Pharmacokinetic data for (188)Re-N, N-bis (2-mercaptoethyl)-N',N'-diethylethylenediamine (BMEDA), (188)Re-liposome, and (188)Re-DXR-liposome were obtained for the estimation of absorbed doses in tumors and normal organs. Two colon carcinoma mouse models were employed: subcutaneous growing solid tumor and malignant ascites pervading tumor models. Radiation-dose estimates for normal tissues and tumors were calculated by using the OLINDA/EXM program. An evaluation of a recommended maximum administered activity (MAA) for the nanotargeted drugs was also made. Mean absorbed doses derived from (188)Re-liposome and (188)Re-DXR-liposome in normal tissues were generally similar to those from (188)Re-BMEDA in intraperitoneal and intravenous administration. Tissue-absorbed dose in the liver was 0.24-0.40 and 0.17-0.26 (mGy/MBq) and in red marrow was 0.033-0.050 and 0.038-0.046 (mGy/MBq), respectively, for (188)Re-liposome and (188)Re-DXR-liposome. Tumor-absorbed doses for the nanotargeted (188)Re-liposome and (188)Re-DXR-liposome were higher than those of (188)Re-BMEDA for both routes of administration (4-26-fold). Dose to red marrow defined the recommended MAA. Our results suggest that radionuclide and chemoradiotherapeutic passive targeting delivery, using nanoliposomes as the carrier, is feasible and promising in systemic-targeted radionuclide therapy.

40 CFR 18.8 - Stipends, Allowances, and Benefits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to some other place at no greater cost to the Government. An Environmental Protection Research fellow....8 Section 18.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL ENVIRONMENTAL PROTECTION RESEARCH FELLOWSHIPS AND SPECIAL RESEARCH CONSULTANTS FOR ENVIRONMENTAL PROTECTION § 18.8 Stipends...

46 CFR 188.10-53 - Oceanographic research vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and other marine geophysical or geological surveys, atmospheric research, and biological research... 46 Shipping 7 2014-10-01 2014-10-01 false Oceanographic research vessel. 188.10-53 Section 188.10-53 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS...

46 CFR 188.10-53 - Oceanographic research vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and other marine geophysical or geological surveys, atmospheric research, and biological research... 46 Shipping 7 2012-10-01 2012-10-01 false Oceanographic research vessel. 188.10-53 Section 188.10-53 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS...

46 CFR 188.10-53 - Oceanographic research vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and other marine geophysical or geological surveys, atmospheric research, and biological research... 46 Shipping 7 2013-10-01 2013-10-01 false Oceanographic research vessel. 188.10-53 Section 188.10-53 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS...

46 CFR 188.10-53 - Oceanographic research vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... and other marine geophysical or geological surveys, atmospheric research, and biological research... 46 Shipping 7 2011-10-01 2011-10-01 false Oceanographic research vessel. 188.10-53 Section 188.10-53 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS...

46 CFR 188.10-53 - Oceanographic research vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... and other marine geophysical or geological surveys, atmospheric research, and biological research... 46 Shipping 7 2010-10-01 2010-10-01 false Oceanographic research vessel. 188.10-53 Section 188.10-53 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS...

7 CFR 800.188 - Crop year, variety, and origin statements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Crop year, variety, and origin statements. 800.188 Section 800.188 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION... REGULATIONS Duties and Conduct of Licensed and Authorized Personnel § 800.188 Crop year, variety, and origin...

7 CFR 800.188 - Crop year, variety, and origin statements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 7 2014-01-01 2014-01-01 false Crop year, variety, and origin statements. 800.188 Section 800.188 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION... REGULATIONS Duties and Conduct of Licensed and Authorized Personnel § 800.188 Crop year, variety, and origin...

7 CFR 800.188 - Crop year, variety, and origin statements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 7 2012-01-01 2012-01-01 false Crop year, variety, and origin statements. 800.188 Section 800.188 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION... REGULATIONS Duties and Conduct of Licensed and Authorized Personnel § 800.188 Crop year, variety, and origin...

7 CFR 800.188 - Crop year, variety, and origin statements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 7 2013-01-01 2013-01-01 false Crop year, variety, and origin statements. 800.188 Section 800.188 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION... REGULATIONS Duties and Conduct of Licensed and Authorized Personnel § 800.188 Crop year, variety, and origin...

7 CFR 800.188 - Crop year, variety, and origin statements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 7 2011-01-01 2011-01-01 false Crop year, variety, and origin statements. 800.188 Section 800.188 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION... REGULATIONS Duties and Conduct of Licensed and Authorized Personnel § 800.188 Crop year, variety, and origin...

The structure, bond strength and apatite-inducing ability of micro-arc oxidized tantalum and their response to annealing

NASA Astrophysics Data System (ADS)

Wang, Cuicui; Wang, Feng; Han, Yong

2016-01-01

In this study, the tantalum oxide coatings were formed on pure tantalum (Ta) by micro-arc oxidation (MAO) in electrolytic solutions of calcium acetate and β-glycerophosphate disodium, and the effect of the applied voltage on the microstructure and bond strength of the MAO coatings was systematically investigated. The effect of annealing treatment on the microstructure, bond strength and apatite-inducing ability of the MAO coatings formed at 350 and 450 V was also studied. The study revealed that during the preparation of tantalum oxide coatings on Ta substrate by MAO, the applied voltage considerably affected the phase components, morphologies and bond strength of the coatings, but had little effect on surface chemical species. After annealing treatment, newly formed CaTa4O11 phase mainly contributed to the much more stronger apatite-inducing ability of the annealed tantalum oxide coatings than those that were not annealed. The better apatite-inducing ability of the MAO coatings formed at 450 V compared to those formed at 350 V was attributed to the less amorphous phase and more crystalline phase as well as more Ca and P contained in the MAO coatings with increasing the applied voltage.

46 CFR 188.05-5 - Specific application noted in text.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Specific application noted in text. 188.05-5 Section 188.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-5 Specific application noted in text. (a) At the beginning of the...

46 CFR 188.05-5 - Specific application noted in text.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Specific application noted in text. 188.05-5 Section 188.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-5 Specific application noted in text. (a) At the beginning of the...

19 CFR 122.188 - Issuance of temporary Customs access seal.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 19 Customs Duties 1 2012-04-01 2012-04-01 false Issuance of temporary Customs access seal. 122.188 Section 122.188 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Access to Customs Security Areas § 122.188 Issuance of...

19 CFR 122.188 - Issuance of temporary Customs access seal.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 19 Customs Duties 1 2014-04-01 2014-04-01 false Issuance of temporary Customs access seal. 122.188 Section 122.188 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Access to Customs Security Areas § 122.188 Issuance of...

46 CFR 188.05-5 - Specific application noted in text.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Specific application noted in text. 188.05-5 Section 188.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-5 Specific application noted in text. (a) At the beginning of the...

46 CFR 188.05-5 - Specific application noted in text.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Specific application noted in text. 188.05-5 Section 188.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-5 Specific application noted in text. (a) At the beginning of the...

19 CFR 122.188 - Issuance of temporary Customs access seal.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 19 Customs Duties 1 2013-04-01 2013-04-01 false Issuance of temporary Customs access seal. 122.188 Section 122.188 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Access to Customs Security Areas § 122.188 Issuance of...

46 CFR 188.05-5 - Specific application noted in text.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Specific application noted in text. 188.05-5 Section 188.05-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-5 Specific application noted in text. (a) At the beginning of the...

46 CFR 188.10-59 - Recognized classification society.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Recognized classification society. 188.10-59 Section 188.10-59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH... classification society. This term means the American Bureau of Shipping or other classification society...

46 CFR 188.10-59 - Recognized classification society.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Recognized classification society. 188.10-59 Section 188.10-59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH... classification society. This term means the American Bureau of Shipping or other classification society...

Design, Development, manufacture and qualification of wet-slug all-tantalum capacitors

NASA Technical Reports Server (NTRS)

Maher, R. H.

1977-01-01

Specifications and qualification tests data are presented for over eleven hundred T3 case all-tantalum capacitors encompassing four ratings. The finalized product has all the advantages of the silver cased wet and is capable of withstanding some reverse potential ac ripple current.

Physics of Shock Compression and Release: NEMD Simulations of Tantalum and Silicon

NASA Astrophysics Data System (ADS)

Hahn, Eric; Meyers, Marc; Zhao, Shiteng; Remington, Bruce; Bringa, Eduardo; Germann, Tim; Ravelo, Ramon; Hammerberg, James

2015-06-01

Shock compression and release allow us to evaluate physical deformation and damage mechanisms occurring in extreme environments. SPaSM and LAMMPS molecular dynamics codes were employed to simulate single and polycrystalline tantalum and silicon at strain rates above 108 s-1. Visualization and analysis was accomplished using OVITO, Crystal Analysis Tool, and a redesigned orientation imaging function implemented into SPaSM. A comparison between interatomic potentials for both Si and Ta (as pertaining to shock conditions) is conducted and the influence on phase transformation and plastic relaxation is discussed. Partial dislocations, shear induced disordering, and metastable phase changes are observed in compressed silicon. For tantalum, the role of grain boundary and twin intersections are evaluated for their role in ductile spallation. Finally, the temperature dependent response of both Ta and Si is investigated.

Intraoperative Localization of Tantalum Markers for Proton Beam Radiation of Choroidal Melanoma by an Opto-Electronic Navigation System: A Novel Technique

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

Amstutz, Christoph A., E-mail: christoph.amstutz@usz.ch; Bechrakis, Nikolaos E.; Foerster, Michael H.

2012-03-15

Purpose: External beam proton radiation therapy has been used since 1975 to treat choroidal melanoma. For tumor location determination during proton radiation treatment, surgical tantalum clips are registered with image data. This report introduces the intraoperative application of an opto-electronic navigation system to determine with high precision the position of the tantalum markers and their spatial relationship to the tumor and anatomical landmarks. The application of the technique in the first 4 patients is described. Methods and Materials: A navigated reference base was attached noninvasively to the eye, and a navigated pointer device was used to record the spatial positionmore » of the tantalum markers, the tumor, and anatomical landmarks. Measurement accuracy was assessed on ex vivo porcine eye specimen by repetitive recording of the tantalum marker positions. The method was applied intraoperatively on 4 patients undergoing routine tantalum clip surgery. The spatial position information delivered by the navigation system was compared to the geometric data generated by the EYEPLAN software. Results: In the ex vivo experiments, the maximum repetition error was 0.34 mm. For the intraoperative application, the root mean square error of paired-points matching of the marker positions from the navigation system and from the EYEPLAN software was 0.701-1.25 mm. Conclusions: Navigation systems are a feasible tool for accurate localization of tantalum markers and anatomic landmarks. They can provide additional geometric information, and therefore have the potential to increase the reliability and accuracy of external beam proton radiation therapy for choroidal melanoma.« less

Novel hierarchical tantalum oxide-PDMS hybrid coating for medical implants: One pot synthesis, characterization and modulation of fibroblast proliferation.

PubMed

Tran, Phong A; Fox, Kate; Tran, Nhiem

2017-01-01

Surface properties such as morphology, roughness and charge density have a strong influence on the interaction of biomaterials and cells. Hierarchical materials with a combination of micron/submicron and nanoscale features for coating of medical implants could therefore have significant potential to modulate cellular responses and eventually improve the performance of the implants. In this study, we report a simple, one pot wet chemistry preparation of a hybrid coating system with hierarchical surface structures consisting of polydimethylsiloxane (PDMS) and tantalum oxide. Medical grade, amine functional PDMS was mixed with tantalum ethoxide which subsequently formed Ta 2 O 5 in situ through hydrolysis and condensation during coating process. The coatings were characterized by SEM, EDS, XPS, confocal scanning microscopy, contact angle measurement and in vitro cell culture. Varying PDMS and tantalum ethoxide ratios resulted in coatings of different surface textures ranging from smooth to submicro- and nano-structured. Strikingly, hierarchical surfaces containing both microscale (1-1.5μm) and nanoscale (86-163nm) particles were found on coatings synthesized with 20% and 40% (v/v) tantalum ethoxide. The coatings were similar in term of hydrophobicity but showed different surface roughness and chemical composition. Importantly, higher cell proliferation was observed on hybrid surface with hierarchical structures compared to pure PDMS or pure tantalum oxide. The coating process is simple, versatile, carried out under ambient condition and requires no special equipment. Copyright © 2016 Elsevier Inc. All rights reserved.

Poloxamer 188 (p188) as a membrane resealing reagent in biomedical applications.

PubMed

Moloughney, Joseph G; Weisleder, Noah

2012-12-01

Maintenance of the integrity of the plasma membrane is essential for maintenance of cellular function and prevention of cell death. Since the plasma membrane is frequently exposed to a variety of mechanical and chemical insults the cell has evolved active processes to defend against these injuries by resealing disruptions in the plasma membrane. Cell membrane repair is a conserved process observed in nearly every cell type where intracellular vesicles are recruited to sites of membrane disruption where they can fuse with themselves or the plasma membrane to create a repair patch. When disruptions are extensive or there is an underlying pathology that reduces the membrane repair capacity of a cell this defense mechanism may prove insufficient and the cell could die due to breakdown of the plasma membrane. Extensive loss of cells can compromise the integrity and function of tissues and leading to disease. Thus, methods to increase membrane resealing capacity could have broad utility in a number of disease states. Efforts to find reagents that can modulate plasma membrane reseal found that specific tri-block copolymers, such as poloxamer 188 (P188, or Pluronic F68), can increase the structural stability and resealing of the plasma membrane. Here we review several current patents and patent applications that present inventions making use of P188 and other copolymers to treat specific disease states such as muscular dystrophy, heart failure, neurodegenerative disorders and electrical injuries, or to facilitate biomedical applications such as transplantation. There appears to be promise for the application of poloxamers in the treatment of various diseases, however there are potential concerns with toxicity with long term application and bioavailability in some cases.

34 CFR 222.188 - What priorities may the Secretary establish?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false What priorities may the Secretary establish? 222.188 Section 222.188 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY... Construction Grant Program Under Section 8007(b) of the Act How Grants Are Made § 222.188 What priorities may...

34 CFR 222.188 - What priorities may the Secretary establish?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 34 Education 1 2013-07-01 2013-07-01 false What priorities may the Secretary establish? 222.188 Section 222.188 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY... Construction Grant Program Under Section 8007(b) of the Act How Grants Are Made § 222.188 What priorities may...

34 CFR 222.188 - What priorities may the Secretary establish?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 34 Education 1 2012-07-01 2012-07-01 false What priorities may the Secretary establish? 222.188 Section 222.188 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY... Construction Grant Program Under Section 8007(b) of the Act How Grants Are Made § 222.188 What priorities may...

34 CFR 222.188 - What priorities may the Secretary establish?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 34 Education 1 2014-07-01 2014-07-01 false What priorities may the Secretary establish? 222.188 Section 222.188 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY... Construction Grant Program Under Section 8007(b) of the Act How Grants Are Made § 222.188 What priorities may...

34 CFR 222.188 - What priorities may the Secretary establish?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 1 2011-07-01 2011-07-01 false What priorities may the Secretary establish? 222.188 Section 222.188 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY... Construction Grant Program Under Section 8007(b) of the Act How Grants Are Made § 222.188 What priorities may...

21 CFR 133.188 - Semisoft part-skim cheeses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Semisoft part-skim cheeses. 133.188 Section 133...) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.188 Semisoft part-skim cheeses. (a) The cheeses for which definitions...

Effect of oxygen deficiency on electronic properties and local structure of amorphous tantalum oxide thin films

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

Denny, Yus Rama; Firmansyah, Teguh; Oh, Suhk Kun

2016-10-15

Highlights: • The effect of oxygen flow rate on electronic properties and local structure of tantalum oxide thin films was studied. • The oxygen deficiency induced the nonstoichiometric state a-TaOx. • A small peak at 1.97 eV above the valence band side appeared on nonstoichiometric Ta{sub 2}O{sub 5} thin films. • The oxygen flow rate can change the local electronic structure of tantalum oxide thin films. - Abstract: The dependence of electronic properties and local structure of tantalum oxide thin film on oxygen deficiency have been investigated by means of X-ray photoelectron spectroscopy (XPS), Reflection Electron Energy Loss Spectroscopy (REELS),more » and X-ray absorption spectroscopy (XAS). The XPS results showed that the oxygen flow rate change results in the appearance of features in the Ta 4f at the binding energies of 23.2 eV, 24.4 eV, 25.8, and 27.3 eV whose peaks are attributed to Ta{sup 1+}, Ta{sup 2+}, Ta{sup 3+}/Ta{sup 4+}, and Ta{sup 5+}, respectively. The presence of nonstoichiometric state from tantalum oxide (TaOx) thin films could be generated by the oxygen vacancies. In addition, XAS spectra manifested both the increase of coordination number of the first Ta-O shell and a considerable reduction of the Ta-O bond distance with the decrease of oxygen deficiency.« less